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Drake I, Fountain H, Kubba H. Managing recurrent nosebleeds in children: a retrospective review of 718 children attending a nurse-led epistaxis clinic. J Laryngol Otol 2024; 138:431-435. [PMID: 38224038 DOI: 10.1017/s0022215124000069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
OBJECTIVE This review assessed the effectiveness of the nurse-led children's epistaxis clinic in streamlining patient care and avoiding unnecessary general anaesthesia. METHODS A retrospective case note review was conducted of children attending the nurse-led epistaxis clinic between 2019 and 2021. RESULTS A total of 718 children were seen over three years. Twelve (1.7 per cent) had a known coagulopathy. Of the children, 590 (82 per cent) had visible vessels and 29 (4 per cent) had mucosal crusting. Silver nitrate cautery was attempted under topical anaesthesia in 481 children, with 463 (96 per cent) successful cauterisations. Fifteen (3 per cent) were cauterised under general anaesthesia. Of the children, 706 (99 per cent) were prescribed nasal antiseptic preparations; this was the sole treatment for 58 (8 per cent). Blood investigations were requested for eight children (1 per cent) and haematology referral for three (0.4 per cent). CONCLUSION This is the largest published series of children's nosebleeds. Given the short-lived benefit from cautery, it is suggested that general anaesthesia should not be offered routinely. However, improved haematology referral criteria are required to increase underlying diagnosis.
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Affiliation(s)
- Ivy Drake
- Department of Paediatric Otolaryngology, Royal Hospital for Children, Glasgow, Scotland, UK
| | - Hazel Fountain
- Department of Paediatric Otolaryngology, Royal Hospital for Children, Glasgow, Scotland, UK
| | - Haytham Kubba
- Department of Paediatric Otolaryngology, Royal Hospital for Children, Glasgow, Scotland, UK
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Liu Y, Yang L, Singh S, Beyer LA, Prieskorn DM, Swiderski DL, Groves AK, Raphael Y. Combinatorial Atoh1, Gfi1, Pou4f3, and Six1 gene transfer induces hair cell regeneration in the flat epithelium of mature guinea pigs. Hear Res 2024; 441:108916. [PMID: 38103445 DOI: 10.1016/j.heares.2023.108916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 10/29/2023] [Accepted: 11/14/2023] [Indexed: 12/19/2023]
Abstract
Flat epithelium (FE) is a condition characterized by the loss of both hair cells (HCs) and supporting cells and the transformation of the organ of Corti into a simple flat or cuboidal epithelium, which can occur after severe cochlear insults. The transcription factors Gfi1, Atoh1, Pou4f3, and Six1 (GAPS) play key roles in HC differentiation and survival in normal ears. Previous work using a single transcription factor, Atoh1, to induce HC regeneration in mature ears in vivo usually produced very few cells and failed to produce HCs in severely damaged organs of Corti, especially those with FE. Studies in vitro suggested combinations of transcription factors may be more effective than any single factor, thus the current study aims to examine the effect of co-overexpressing GAPS genes in deafened mature guinea pig cochleae with FE. Deafening was achieved through the infusion of neomycin into the perilymph, leading to the formation of FE and substantial degeneration of nerve fibers. Seven days post neomycin treatment, adenovirus vectors carrying GAPS were injected into the scala media and successfully expressed in the FE. One or two months following GAPS inoculation, cells expressing Myosin VIIa were observed in regions under the FE (located at the scala tympani side of the basilar membrane), rather than within the FE. The number of cells, which we define as induced HCs (iHCs), was not significantly different between one and two months, but the larger N at two months made it more apparent that there were significantly more iHCs in GAPS treated animals than in controls. Additionally, qualitative observations indicated that ears with GAPS gene expression in the FE had more nerve fibers than FE without the treatment. In summary, our results showed that co-overexpression of GAPS enhances the potential for HC regeneration in a severe lesion model of FE.
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Affiliation(s)
- Yujie Liu
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA; Department of Otolaryngology-Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Ministry of Education Key Laboratory of Otolaryngology-Head and Neck Surgery, Beijing 100730, China
| | - Lin Yang
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA; Department of Otolaryngology-Head and Neck Surgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Sunita Singh
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
| | - Lisa A Beyer
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Diane M Prieskorn
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Donald L Swiderski
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Andrew K Groves
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Yehoash Raphael
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA.
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Qi L, Zhang J, Liu Q, Gao X. Ligand "switching on" fluorescence of HIV-1 RNA-templated copper nanoclusters for ligand-RNA interaction assays. Int J Biol Macromol 2024; 256:127779. [PMID: 37981280 DOI: 10.1016/j.ijbiomac.2023.127779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/15/2023] [Accepted: 10/27/2023] [Indexed: 11/21/2023]
Abstract
Ligand-RNA interaction assay provides the basis for developing new RNA-binding small molecules. In this study, fluorescent copper nanoclusters (CuNCs) were first prepared using two kinds of HIV-1 RNA targets, rev-responsive element (RRE) and transactivator response element (TAR) RNA, as new templates, and it was found that the fluorescence of the single RNA-templated CuNCs was negligible. Using neomycin as a model drug, the fluorescence could be augmented (approximately 6 times) for the neomycin/RNA-templated CuNCs. Thus, a novel method was developed for ligand-RNA interactions by observing the fluorescence changes in CuNCs prepared using RNA before and after the addition of ligands. The preparation parameters of neomycin/RNA-CuNCs were optimized. The as-prepared CuNCs were characterized using UV-vis spectroscopy, fluorescence spectroscopy, and high-resolution transmission electron microscope. Circular dichroism spectral analysis showed that RRE and TAR were inclined to form a double-stranded structure after interaction with neomycin, which was more conducive to the formation of CuNCs. The interactions of neomycin and three test drugs (amikacin, gentamicin, and tobramycin) with RNA were investigated using the proposed method, and the binding constants and number of binding sites were obtained through theoretical calculations. This study provides a novel approach for ligand-RNA interaction assays.
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Affiliation(s)
- Liang Qi
- School of Biomedical and Pharmaceutical Sciences, Shaanxi University of Science & Technology, Xi'an 710021, China.
| | - Jiayun Zhang
- School of Biomedical and Pharmaceutical Sciences, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Qiaoning Liu
- School of Biomedical and Pharmaceutical Sciences, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Xiang Gao
- School of Biomedical and Pharmaceutical Sciences, Shaanxi University of Science & Technology, Xi'an 710021, China.
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Cheng P, Meng K, Shi X, Jiao M, Han Y, Li X, Liu P, Xiao C. Solid-phase extraction with the functionalization of calcium-sensing receptors onto magnetic microspheres as an affinity probe can capture ligands selectively from herbal extract. Mikrochim Acta 2023; 191:34. [PMID: 38108923 DOI: 10.1007/s00604-023-06092-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 11/06/2023] [Indexed: 12/19/2023]
Abstract
Magnetic solid phase extraction with the functionalization of protein onto micro- or nano-particles as a probe is favorable for the discovery of new drugs from complicated natural products. Herein, we aimed to develop a rapid method by immobilizing halogenated alkane dehalogenase (Halo)-tagged calcium-sensing receptor (CaSR) directly out of crude cell lysates onto the surface of magnetic microspheres (MM) with no need to purify protein. Thereby we achieved CaSR-functionalized MM for revealing adsorption characteristics of agonist neomycin and screening ligands from herbal medicine Radix Astragali (RA). About 43.87 mg CaSR could be immobilized per 1 g MM within 30 min, and the acquired CaSR-functionalized MM showed good stability and activity for 4 weeks. The maximum adsorption capacity of neomycin on CaSR-functionalized MM was determined as 4.70 × 10-4 ~ 3.96 × 10-4 mol/g within 277 ~ 310 K, and its adsorption isotherm characteristics described best by the Temkin model were further validated using isothermal titration calorimetry. It was inferred that CaSR's affinity for neomycin was driven by electrostatic forces in a spontaneous process when the system reached an equilibrium state. Moreover, the ligands from the RA extract were screened, three of which were assigned as astragaloside IV, ononin, and calycosin based on HPLC-MS. Our findings demonstrated that the functionalization of a receptor onto magnetic materials designed as an affinity probe has the capability to recognize its agonist and capture the ligands selectively from complex matrices like herbs.
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Affiliation(s)
- Peixuan Cheng
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, People's Republic of China
| | - Kaili Meng
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, People's Republic of China
| | - Xiangang Shi
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, People's Republic of China
| | - Meizhi Jiao
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, People's Republic of China
| | - Yaokun Han
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, People's Republic of China
| | - Xia Li
- Shaanxi Institute for Food and Drug Control, Xi'an, 710065, People's Republic of China
| | - Pei Liu
- Shaanxi Institute for Food and Drug Control, Xi'an, 710065, People's Republic of China
| | - Chaoni Xiao
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, People's Republic of China.
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Kanai K, Kageyama S, Yoshie O. Involvement of TLR4 in Acute Hepatitis Associated with Airway Infection of Murine γ-Herpesvirus 68. J Immunol 2023; 211:1550-1560. [PMID: 37772812 DOI: 10.4049/jimmunol.2200653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 09/11/2023] [Indexed: 09/30/2023]
Abstract
Extrahepatic viral infections are often accompanied by acute hepatitis, as evidenced by elevated serum liver enzymes and intrasinusoidal infiltration of CD8+ T cells, without direct infection of the liver. An example is infectious mononucleosis caused by primary infection with EBV. Previously, we demonstrated that airway infection of mice with murine γ-herpesvirus 68 (MHV68), a murine model of EBV, caused liver inflammation with elevated serum liver enzymes and intrahepatic infiltration of IFN-γ-producing CD8+ T cells and NK cells. Mechanistically, the expression of the CXCR3-ligand chemokines, which are commonly induced by IFN-γ and attract IFN-γ-producing Th1-type cells via CXCR3, was upregulated in the liver. Importantly, the liver inflammation was suppressed by oral neomycin, an intestine-impermeable aminoglycoside, suggesting an involvement of some products from the intestinal microbiota. In this study, we showed that the liver inflammation and the expression of the CXCR3-ligand chemokines in the liver were effectively ameliorated by i.p. administration of anti-TLR4 mAb or C34, a TLR4 blocker, as well as in TLR4-deficient mice. Conversely, intrarectal inoculation of Escherichia coli as an extraintestinal source of LPS aggravated liver inflammation in MHV68-infected mice with increased expression of the CXCR3-ligand chemokines in the liver. In contrast, the lung inflammation in MHV68-infected mice was not affected by oral neomycin, i.p. administration of C34, or TLR4 deficiency. Collectively, the LPS-TLR4 pathway plays a pivotal role in the liver inflammation of MHV68-infected mice at least in part by upregulating the CXCR3-ligand chemokines in the liver.
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Affiliation(s)
- Kyosuke Kanai
- Division of Virology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Seiji Kageyama
- Division of Virology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Osamu Yoshie
- Health and Kampo Institute, Sendai, Miyagi, Japan
- Aoinosono Sendai Izumi Long-Term Health Care Facility, Sendai, Miyagi, Japan
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Zhou X, Jin L, Li Y, Wang Y, Li W, Shen X. Comprehensive analysis of N6-methyladenosine-related RNA methylation in the mouse hippocampus after acquired hearing loss. BMC Genomics 2023; 24:577. [PMID: 37759187 PMCID: PMC10537436 DOI: 10.1186/s12864-023-09697-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 09/22/2023] [Indexed: 09/29/2023] Open
Abstract
BACKGROUND The mechanism underlying cognitive impairment after hearing loss (HL) remains unclear. N6-methyladenosine (m6A) is involved in many neurodegenerative diseases; however, its role in cognitive impairment after HL has not yet been investigated. Therefore, we aimed to analyze the m6A modification profile of the mouse hippocampus after HL exposure. A mouse model of neomycin-induced HL was established. An auditory brainstem-response test was utilized for detecting hearing threshold. The passive avoidance test was served as the mean for evaluating cognitive function. The m6A-regulated enzyme expression levels were analyzed by using reverse transcription quantitative real-time polymerase chain reaction and western blot analyses. RNA sequencing (RNA-Seq) and methylated RNA immunoprecipitation sequencing (MeRIP-Seq) were performed with the aim of investigating gene expression differences and m6A modification in the mouse hippocampus. RESULTS Neomycin administration induced severe HL in mice. At four months of age, the mice in the HL group showed poorer cognitive performance than the mice in the control group. METTL14, WTAP, and YTHDF2 mRNA levels were downregulated in the hippocampi of HL mice, whereas ALKBH5 and FTO mRNA levels were significantly upregulated. At the protein level, METTL3 and FTO were significantly upregulated. Methylated RNA immunoprecipitation sequencing analysis revealed 387 and 361 m6A hypermethylation and hypomethylation peaks, respectively. Moreover, combined analysis of mRNA expression levels and m6A peaks revealed eight mRNAs with significantly changed expression levels and methylation. CONCLUSIONS Our findings revealed the m6A transcriptome-wide profile in the hippocampus of HL mice, which may provide a basis for understanding the association between HL and cognitive impairment from the perspective of epigenetic modifications.
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Affiliation(s)
- Xuehua Zhou
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, 200031, Shanghai, China
| | - Lin Jin
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, 200031, Shanghai, China
| | - Yufeng Li
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, 200031, Shanghai, China
| | - Yiru Wang
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, 200031, Shanghai, China
| | - Wen Li
- ENT Institute, Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, 200031, Shanghai, China
| | - Xia Shen
- Department of Anesthesiology, Eye & ENT Hospital, Fudan University, 83 Fenyang Road, 200031, Shanghai, China.
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Kobayashi Y, Sugahara K, Takemoto Y, Tsuda J, Hirose Y, Hashimoto M, Yamashita H. Protective effect of astaxanthin nanoemulsion on mammalian inner ear hair cells. PeerJ 2023; 11:e15562. [PMID: 37701833 PMCID: PMC10494832 DOI: 10.7717/peerj.15562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 05/24/2023] [Indexed: 09/14/2023] Open
Abstract
Background Aminoglycoside antibiotics are used for treating certain acute infections. However, these drugs cause ototoxicity by inducing inner ear hair cell death. Aims/Objectives We investigated the protective effect of a nanoemulsion of the carotenoid astaxanthin on mammalian inner ear hair cells against neomycin-induced ototoxicity. Material and Methods Dose-response relationship, quantification of hair cell loss, and reactive oxygen species production were assayed in response to neomycin with and without astaxanthin in cultured utricles of CBA/N mice. In addition, auditory brain response (ABR) and hair cell loss after exposure to the nanoformulation and loud noise were examined in vivo in guinea pigs. Results Astaxanthin suppressed neomycin-induced reduction of hair cells by reducing the production of hydroxy radicals. Furthermore, hair cell loss in the second rotation of the cochlea was significantly lower in the astaxanthin group than in the noise-only group. Conclusions and Significance The blood-labyrinth barrier limits the successful delivery of drugs for inner ear complications. However, in the nanoemulsion form, astaxanthin can penetrate the round window (fenestra ovale) membrane, enabling topical administration. Thus, astaxanthin nanoemulsion could be useful in treating ototoxicity in individuals with inner ear complications.
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Affiliation(s)
- Yuki Kobayashi
- Department of Otolaryngology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Kazuma Sugahara
- Department of Otolaryngology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Yosuke Takemoto
- Department of Otolaryngology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Junko Tsuda
- Department of Otolaryngology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Yoshinobu Hirose
- Department of Otolaryngology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Makoto Hashimoto
- Department of Otolaryngology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
| | - Hiroshi Yamashita
- Department of Otolaryngology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi, Japan
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Alekseeva MG, Rudakova NN, Ratkin AV, Mavletova DA, Danilenko VN. Resistome in Streptomyces rimosus - A Reservoir of Aminoglycoside Antibiotics Resistance Genes. Biochemistry (Mosc) 2023; 88:723-730. [PMID: 37748869 DOI: 10.1134/s0006297923060019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/20/2023] [Accepted: 04/20/2023] [Indexed: 09/27/2023]
Abstract
Investigation of aminoglycoside acetyltransferases in actinobacteria of the genus Streptomyces is an integral part of the study of soil bacteria as the main reservoir and possible source of drug resistance genes. Previously, we have identified and biochemically characterized three aminoglycoside phosphotransferases, which cause resistance to kanamycin, neomycin, paromomycin, streptomycin, and hygromycin B in the strain Streptomyces rimosus ATCC 10970 (producing oxytetracycline), which is resistant to most natural aminoglycoside antibiotics. In the presented work, it was shown that the resistance of this strain to other AGs is associated with the presence of the enzyme aminoglycoside acetyltransferase, belonging to the AAC(2') subfamily. Induction of the expression of the gene, designated by us as aac(2')-If, in Escherichia coli cells determines resistance to a wide range of natural aminoglycoside antibiotics (neomycin, gentamicin, tobramycin, sisomycin, and paromomycin) and increases minimum inhibitory concentrations of these antibiotics.
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Affiliation(s)
- Maria G Alekseeva
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia.
| | - Natalya N Rudakova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Anatoly V Ratkin
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Dilara A Mavletova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Valeriy N Danilenko
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia
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Koo CH, Chok AY, Wee IJY, Seow-En I, Zhao Y, Tan EJKW. Effect of preoperative oral antibiotics and mechanical bowel preparation on the prevention of surgical site infection in elective colorectal surgery, and does oral antibiotic regime matter? a bayesian network meta-analysis. Int J Colorectal Dis 2023; 38:151. [PMID: 37256453 DOI: 10.1007/s00384-023-04444-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/24/2023] [Indexed: 06/01/2023]
Abstract
PURPOSE Surgical site infection (SSI) impacts 5-20% of patients after elective colorectal surgery. There are varying reports on the effectiveness of oral antibiotics (OAB) with preoperative mechanical bowel preparation (MBP) in preventing SSI. We aim to determine the role of OAB and MBP in preventing SSI after elective colorectal surgery. We also determine if a specific OAB regimen will be more effective than others. METHODS This study investigated the impact of OAB and MBP in patients undergoing elective colorectal surgery. PubMed, MEDLINE, Ovid, Cochrane Central Register of Controlled Trials, ACP Journal Club, and Embase databases were searched for randomized clinical trials (RCTs) published by June 2022. All RCTs comparing various preoperative bowel preparation regimens, including pairwise or multi-intervention comparisons, were included. To establish the role of OAB and MBP in preventing SSI, we conducted a Bayesian network meta-analysis on all RCTs. We further performed subgroup analysis to determine the most effective OAB regimen. RESULTS Among included 46 studies with a total of 12690 patients, patients in the MBP + OAB group were less likely to have SSI than those having MBP-only (OR 0.55, 95% CrI 0.39-0.76), and without MBP and OAB (OR 0.52, 95% CrI 0.32-0.84). OAB regimen C (kanamycin + metronidazole) and A (neomycin + metronidazole) demonstrated a significantly reduced incidence of SSI, compared to regimen B (neomycin + erythromycin) with OR 0.24 (95% CrI 0.07-0.79) and 0.26 (95% CrI 0.07-0.99) respectively. CONCLUSIONS OAB with MBP reduces the risk of SSI after elective colorectal surgery. Providing adequate aerobic and anaerobic coverage with OAB may confer better protection against SSI.
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Affiliation(s)
- Chee Hoe Koo
- Department of Colorectal Surgery, Singapore General Hospital, Academia, 20 College Road, Singapore, 169608, Singapore.
| | - Aik Yong Chok
- Department of Colorectal Surgery, Singapore General Hospital, Academia, 20 College Road, Singapore, 169608, Singapore
| | - Ian Jun Yan Wee
- Department of Colorectal Surgery, Singapore General Hospital, Academia, 20 College Road, Singapore, 169608, Singapore
| | - Isaac Seow-En
- Department of Colorectal Surgery, Singapore General Hospital, Academia, 20 College Road, Singapore, 169608, Singapore
| | - Yun Zhao
- Department of Colorectal Surgery, Singapore General Hospital, Academia, 20 College Road, Singapore, 169608, Singapore
- Group Finance Analytics, Singapore Health Services, Singapore, 168582, Singapore
| | - Emile John Kwong Wei Tan
- Department of Colorectal Surgery, Singapore General Hospital, Academia, 20 College Road, Singapore, 169608, Singapore
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Johnson G, Ziegler J, Helewa R, Askin N, Rabbani R, Abou-Setta AM. Preoperative oral fluoroquinolone antibiotics in elective colorectal surgery to prevent surgical site infections: a systematic review and meta-analysis. Can J Surg 2023; 66:E21-E31. [PMID: 36653030 PMCID: PMC9854941 DOI: 10.1503/cjs.019721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2022] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Preoperative treatment with oral neomycin combined with erythromycin or metronidazole is recommended to decrease the risk of surgical site infections (SSIs) in elective colorectal surgery. However, oral neomycin is not commercially available in Canada, and therefore it is not routinely used. Fluoroquinolones are widely available and have excellent activity against aerobic Gram-negative bacteria. The aim of this systematic review was to identify, critically appraise and summarize the evidence on the efficacy and safety of preoperative use of oral fluoroquinolone antibiotics for the prevention of SSIs in adult patients undergoing elective colorectal resection. METHODS Following Cochrane guidelines, we included English-language randomized controlled trials (RCTs) comparing oral fluoroquinolones plus routine preoperative intravenous antibiotics against intravenous antibiotics alone from MEDLINE (Ovid), Embase (Ovid), the Cochrane Central Register of Controlled Trials( Ovid) and ClinicalTrials.gov. RESULTS We included 3 RCTs (1136 patients). Risk of bias was uncertain in 2 trials and high in 1 trial. Preoperative oral fluoroquinolones led to significantly decreased total SSIs (risk ratio [RR] 0.43, 95% confidence interval [CI] 0.32-0.57, I 2 = 0%), superficial incisional (RR 0.38, 95% CI 0.22-0.68, I 2 = 32%), deep incisional (RR 0.19, 95% CI 0.06-0.65, I 2 = 0%) and organ/space SSIs (RR 0.34, 95% CI 0.12-0.90, I 2 = 33%). There was also a significant reduction in anastomotic leaks (RR 0.22, 95% CI 0.06-0.87, I 2 = 0%). No antibiotic-related adverse events were reported. CONCLUSION This review suggests that preoperative oral fluoroquinolones with intravenous antibiotics are superior to intravenous antibiotics alone for preventing SSIs after colorectal surgery. If neomycin is unavailable, oral fluoroquinolones should be considered as a reasonable alternative. Future trials are required to further compare the relative efficacy of oral antibiotic regimens.
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Affiliation(s)
- Garrett Johnson
- From the Department of Surgery, Section of General Surgery, University of Manitoba, Winnipeg, Man. (Johnson, Helewa); the Clinician Investigator Program, University of Manitoba, Winnipeg, Man. (Johnson); the Department of Internal Medicine, University of Manitoba, Winnipeg, Man. (Ziegler); the University of Manitoba, Winnipeg, Man. (Askin); the George & Fay Yee Centre for Healthcare Innovation, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta); and the Department of Community Health Sciences, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta)
| | - Jennifer Ziegler
- From the Department of Surgery, Section of General Surgery, University of Manitoba, Winnipeg, Man. (Johnson, Helewa); the Clinician Investigator Program, University of Manitoba, Winnipeg, Man. (Johnson); the Department of Internal Medicine, University of Manitoba, Winnipeg, Man. (Ziegler); the University of Manitoba, Winnipeg, Man. (Askin); the George & Fay Yee Centre for Healthcare Innovation, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta); and the Department of Community Health Sciences, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta)
| | - Ramzi Helewa
- From the Department of Surgery, Section of General Surgery, University of Manitoba, Winnipeg, Man. (Johnson, Helewa); the Clinician Investigator Program, University of Manitoba, Winnipeg, Man. (Johnson); the Department of Internal Medicine, University of Manitoba, Winnipeg, Man. (Ziegler); the University of Manitoba, Winnipeg, Man. (Askin); the George & Fay Yee Centre for Healthcare Innovation, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta); and the Department of Community Health Sciences, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta)
| | - Nicole Askin
- From the Department of Surgery, Section of General Surgery, University of Manitoba, Winnipeg, Man. (Johnson, Helewa); the Clinician Investigator Program, University of Manitoba, Winnipeg, Man. (Johnson); the Department of Internal Medicine, University of Manitoba, Winnipeg, Man. (Ziegler); the University of Manitoba, Winnipeg, Man. (Askin); the George & Fay Yee Centre for Healthcare Innovation, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta); and the Department of Community Health Sciences, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta)
| | - Rasheda Rabbani
- From the Department of Surgery, Section of General Surgery, University of Manitoba, Winnipeg, Man. (Johnson, Helewa); the Clinician Investigator Program, University of Manitoba, Winnipeg, Man. (Johnson); the Department of Internal Medicine, University of Manitoba, Winnipeg, Man. (Ziegler); the University of Manitoba, Winnipeg, Man. (Askin); the George & Fay Yee Centre for Healthcare Innovation, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta); and the Department of Community Health Sciences, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta)
| | - Ahmed M Abou-Setta
- From the Department of Surgery, Section of General Surgery, University of Manitoba, Winnipeg, Man. (Johnson, Helewa); the Clinician Investigator Program, University of Manitoba, Winnipeg, Man. (Johnson); the Department of Internal Medicine, University of Manitoba, Winnipeg, Man. (Ziegler); the University of Manitoba, Winnipeg, Man. (Askin); the George & Fay Yee Centre for Healthcare Innovation, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta); and the Department of Community Health Sciences, University of Manitoba, Winnipeg, Man. (Rabbani, Abou-Setta)
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11
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de Castro RJA, Rêgo MTAM, Brandão FS, Pérez ALA, De Marco JL, Poças-Fonseca MJ, Nichols C, Alspaugh JA, Felipe MSS, Alanio A, Bocca AL, Fernandes L. Engineered Fluorescent Strains of Cryptococcus neoformans: a Versatile Toolbox for Studies of Host-Pathogen Interactions and Fungal Biology, Including the Viable but Nonculturable State. Microbiol Spectr 2022; 10:e0150422. [PMID: 36005449 PMCID: PMC9603711 DOI: 10.1128/spectrum.01504-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 08/05/2022] [Indexed: 12/31/2022] Open
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen known for its remarkable ability to infect and subvert phagocytes. This ability provides survival and persistence within the host and relies on phenotypic plasticity. The viable but nonculturable (VBNC) phenotype was recently described in C. neoformans, whose study is promising in understanding the pathophysiology of cryptococcosis. The use of fluorescent strains is improving host interaction research, but it is still underexploited. Here, we fused histone H3 or the poly(A) binding protein (Pab) to enhanced green fluorescent protein (eGFP) or mCherry, obtaining a set of C. neoformans transformants with different colors, patterns of fluorescence, and selective markers (hygromycin B resistance [Hygr] or neomycin resistance [Neor]). We validated their similarity to the parental strain in the stress response, the expression of virulence-related phenotypes, mating, virulence in Galleria mellonella, and survival within murine macrophages. PAB-GFP, the brightest transformant, was successfully applied for the analysis of phagocytosis by flow cytometry and fluorescence microscopy. Moreover, we demonstrated that an engineered fluorescent strain of C. neoformans was able to generate VBNC cells. GFP-tagged Pab1, a key regulator of the stress response, evidenced nuclear retention of Pab1 and the assembly of cytoplasmic stress granules, unveiling posttranscriptional mechanisms associated with dormant C. neoformans cells. Our results support that the PAB-GFP strain is a useful tool for research on C. neoformans. IMPORTANCE Cryptococcus neoformans is a human-pathogenic yeast that can undergo a dormant state and is responsible for over 180,000 deaths annually worldwide. We engineered a set of fluorescent transformants to aid in research on C. neoformans. A mutant with GFP-tagged Pab1 improved fluorescence-based techniques used in host interaction studies. Moreover, this mutant induced a viable but nonculturable phenotype and uncovered posttranscriptional mechanisms associated with dormant C. neoformans. The experimental use of fluorescent mutants may shed light on C. neoformans-host interactions and fungal biology, including dormant phenotypes.
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Affiliation(s)
- Raffael Júnio Araújo de Castro
- Laboratory of Applied Immunology, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District, Brazil
- CNRS, Unité de Mycologie Moléculaire, Centre National de Référence Mycoses et Antifongiques, Institut Pasteur, Paris, France
| | - Marco Túlio Aidar Mariano Rêgo
- Laboratory of Applied Immunology, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District, Brazil
| | - Fabiana S. Brandão
- Faculty of Health Science, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District, Brazil
| | - Ana Laura Alfonso Pérez
- Department of Cell Biology, Institute of Biological Sciences, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasilia, Federal District, Brazil
| | - Janice Lisboa De Marco
- Department of Cell Biology, Institute of Biological Sciences, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasilia, Federal District, Brazil
| | - Marcio José Poças-Fonseca
- Department of Genetics and Morphology, Institute of Biological Sciences, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District, Brazil
| | - Connie Nichols
- Duke University School of Medicine, Department of Medicine, Durham, North Carolina, USA
| | - J. Andrew Alspaugh
- Duke University School of Medicine, Department of Medicine, Durham, North Carolina, USA
| | - Maria Sueli S. Felipe
- Catholic University of Brasilia, Campus Asa Norte, Asa Norte, Brasília, Federal District, Brazil
| | - Alexandre Alanio
- CNRS, Unité de Mycologie Moléculaire, Centre National de Référence Mycoses et Antifongiques, Institut Pasteur, Paris, France
- Laboratoire de Mycologie et Parasitologie, AP-HP, Hôpital Saint Louis, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Anamélia Lorenzetti Bocca
- Laboratory of Applied Immunology, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District, Brazil
| | - Larissa Fernandes
- Laboratory of Applied Immunology, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District, Brazil
- Faculty of Ceilândia, Campus UnB Ceilândia, University of Brasília, Ceilândia Sul, Brasília, Federal District, Brazil
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Harmer CJ, Lebreton F, Stam J, McGann PT, Hall RM. Mechanisms of IS 26-Mediated Amplification of the aphA1 Gene Leading to Tobramycin Resistance in an Acinetobacter baumannii Isolate. Microbiol Spectr 2022; 10:e0228722. [PMID: 36073931 PMCID: PMC9602291 DOI: 10.1128/spectrum.02287-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 08/19/2022] [Indexed: 01/04/2023] Open
Abstract
Enhanced levels of resistance to antibiotics arising from amplification of an antibiotic resistance gene that impact therapeutic options are increasingly observed. Amplification can also disclose novel phenotypes leading to treatment failure. However, the mechanism is poorly understood. Here, the route to amplification of the aphA1 kanamycin and neomycin resistance gene during tobramycin treatment of an Acinetobacter baumannii clinical isolate, leading to tobramycin resistance and treatment failure, was investigated. In the tobramycin-susceptible parent isolate, MRSN56, a single copy of aphA1 is present in the pseudocompound transposon PTn6020, bounded by directly oriented copies of IS26. For two clinical resistant isolates, new long-read sequence data were combined with available short-read data to complete the genomes. Comparison to the completed genome of MRSN56 revealed that, in both cases, IS26 had generated a circular translocatable unit (TU) containing PTn6020 and additional adjacent DNA. In one case, this TU was reincorporated into the second product generated by the deletion that formed the TU via the targeted conservative route and amplified about 7 times. In the second case, the TU was incorporated at a new location via the copy-in route and amplified about 65 times. Experimental amplification ex vivo by subjecting MRSN56 to tobramycin selection pressure yielded different TUs, which were incorporated at either the original location or a new location and amplified many times. The outcomes suggest that when IS26 is involved, amplification occurs via rolling circle replication of a newly formed TU coupled to the IS26-mediated TU formation or reincorporation step. IMPORTANCE Heteroresistance, a significant issue that is known to impact antibiotic treatment outcomes, is caused by the presence of spontaneously arising cells with elevated levels of resistance to therapeutically important antibiotics in a population of susceptible cells. Gene amplification is one well-documented cause of heteroresistance, but precisely how extensive amplification occurs is not understood. Here, we establish the case for the direct involvement of IS26 activity in the amplification of the aphA1 gene to disclose resistance to tobramycin. The aphA1 gene is usually found associated with IS26 in Gram-negative pathogens and is commonly found in extensively resistant Acinetobacter baumannii strains. IS26 and related IS cause adjacent deletions, forming a nonreplicating circular molecule known as a translocatable unit (TU), and amplification via a rolling circle mechanism appears to be coupled to either IS26-mediated TU formation or reincorporation. Related IS found in Gram-positive pathogens may play a similar role.
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Affiliation(s)
- Christopher J. Harmer
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Francois Lebreton
- Multidrug Resistant Organism Repository and Surveillance Network, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Jason Stam
- Multidrug Resistant Organism Repository and Surveillance Network, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Patrick T. McGann
- Multidrug Resistant Organism Repository and Surveillance Network, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Ruth M. Hall
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
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Zhang M, Xue M, Xiao Z, Liu W, Jiang N, Meng Y, Fan Y, Liu X, Zhou Y. Staphylococcus sciuri causes disease and pathological changes in hybrid sturgeon acipenser baerii × acipenser schrencki. Front Cell Infect Microbiol 2022; 12:1029692. [PMID: 36275022 PMCID: PMC9582232 DOI: 10.3389/fcimb.2022.1029692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 09/16/2022] [Indexed: 11/13/2022] Open
Abstract
Hybrid sturgeon is the main species of sturgeon cultured in China, with the advantages of a fast growth rate, early sexual maturity, fertile offspring, and more stable genetic traits. In May 2021, a large number of deaths characterized by superficial hemorrhage and liver damage occurred in a sturgeon farm in Yichang, Hubei Province, which posed a significant risk to hybrid sturgeon captive breeding. We isolated a pathogenic bacterium named D-59 from the diseased sturgeon with apparent symptoms. The pathogen was identified as Staphylococcus sciuri using 16S rRNA gene phylogenetic analysis combined with biochemical identification. Regression experiments showed that D-59 exhibited clinical signs similar to those of diseased sturgeon in the farm after intraperitoneal injection into hybrid sturgeon. High-throughput sequencing of gut microbes in D-59-infected sturgeon showed that the number of gut microbial species decreased in infected sturgeon, the number of some intestinal commensal bacteria decreased, and the balance of the intestinal microorganisms was disrupted. Histopathological sections indicated many inflammatory cells, congestion, and even necrosis in the tissue of diseased sturgeon. Analysis of blood indexes revealed an increase in the proportion of mononuclear cells and a decrease in the proportion of lymphocytes in the peripheral blood of diseased sturgeon. Significantly elevated serum levels of aspartate aminotransferase and alanine aminotransferase, whereas alkaline phosphatase, total protein, albumin, and globulin were decreased in diseased sturgeon. Antimicrobial susceptibility tests demonstrated that D-59 is susceptible to florfenicol, enrofloxacin, and neomycin sulfate. This study aimed to highlight the dangers of Staphylococcus sciuri infection during hybrid sturgeon culture and to provide recommendations for diagnosis and treatment.
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Affiliation(s)
- Mengwei Zhang
- Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan, China
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Mingyang Xue
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Zidong Xiao
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Wei Liu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Nan Jiang
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yan Meng
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yuding Fan
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Xiaoling Liu
- Department of Aquatic Animal Medicine, College of Fisheries, Huazhong Agricultural University, Wuhan, China
- *Correspondence: Xiaoling Liu, ; Yong Zhou,
| | - Yong Zhou
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
- *Correspondence: Xiaoling Liu, ; Yong Zhou,
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14
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Yan S, Ilgu M, Nilsen-Hamilton M, Lamm MH. Computational Modeling of RNA Aptamers: Structure Prediction of the Apo State. J Phys Chem B 2022; 126:7114-7125. [PMID: 36097649 PMCID: PMC9512008 DOI: 10.1021/acs.jpcb.2c04649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/23/2022] [Indexed: 11/28/2022]
Abstract
RNA aptamers are single-stranded oligonucleotides that bind to specific molecular targets with high affinity and specificity. To design aptamers for new applications, it is critical to understand the ligand binding mechanism in terms of the structure and dynamics of the ligand-bound and apo states. The problem is that most of the NMR or X-ray crystal structures available for RNA aptamers are for ligand-bound states. Available apo state structures, mostly characterized by crystallization under nonphysiological conditions or probed by low resolution techniques, might fail to represent the diverse structural variations of the apo state in solution. Here, we develop an approach to obtain a representative ensemble of apo structures that are based on in silico RNA 3D structure prediction and in vitro experiments that characterize base stacking. Using the neomycin-B aptamer as a case study, an ensemble of structures for the aptamer in the apo (unbound) state are validated and then used to investigate the ligand-binding mechanism for the aptamer in complex with neomycin-B.
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Affiliation(s)
- Shuting Yan
- Iowa
State University, Ames, Iowa 50011, United States
| | - Muslum Ilgu
- Iowa
State University, Ames, Iowa 50011, United States
- Ames
National Laboratory, Ames, Iowa 50011, United States
- Aptalogic
Inc., Ames, Iowa 50014, United States
| | - Marit Nilsen-Hamilton
- Iowa
State University, Ames, Iowa 50011, United States
- Ames
National Laboratory, Ames, Iowa 50011, United States
- Aptalogic
Inc., Ames, Iowa 50014, United States
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15
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Jadhav RW, Khobrekar PP, Bugde ST, Bhosale SV. Nanoarchitectonics of neomycin-derived fluorescent carbon dots for selective detection of Fe 3+ ions. Anal Methods 2022; 14:3289-3298. [PMID: 35968579 DOI: 10.1039/d2ay01040b] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The first-ever neomycin antibiotic-based carbon dots (Neo-CDs) were synthesized via a low-cost, eco-friendly, and single-step hydrothermal method using neomycin as a single precursor. The as-prepared Neo-CDs exhibited strong and stable blue fluorescence and were well characterized by TEM, UV-vis absorption, fluorescence emission, IR, XRD, Raman and XPS spectroscopy methods. The Neo-CDs showed a well-distributed size within the range of 4.5 to 7.8 nm, comprising various functional groups on the surface of the carbon core. The Neo-CDs exhibited exceptional emission behaviour, and fluorescence quantum yield was calculated to be 55% in double distilled water. Neo-CDs have been used as a fluorescent sensor for selective and sensitive detection of Fe3+ ions in aqueous solution in the fluorescence turn-off mode. From the set of metal ions, only the Fe3+ ion showed quenching of fluorescence due to photoinduced (PET) electron transfer from Neo-CDs to the half-filled 3d orbital of Fe3+ ions. The limit of detection for Fe3+ ions was calculated to be 0.854 μM. Further, the quenching efficiency and Stern-Volmer quenching constant have been calculated which are about 94% and 5.6 × 106 M-1, respectively.
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Affiliation(s)
- Ratan W Jadhav
- School of Chemical Sciences, Goa University, Taleigao Plateau, Goa-403 206, India.
| | - Pritesh P Khobrekar
- School of Chemical Sciences, Goa University, Taleigao Plateau, Goa-403 206, India.
| | - Sandesh T Bugde
- School of Chemical Sciences, Goa University, Taleigao Plateau, Goa-403 206, India.
| | - Sheshanath V Bhosale
- School of Chemical Sciences, Goa University, Taleigao Plateau, Goa-403 206, India.
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16
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Jiao J, Liu J, Li Q, Zhang G, Pan C, Luo F, Zhang Q, Qi B, Zhao L, Yin P, Shang D. Gut Microbiota-Derived Diaminopimelic Acid Promotes the NOD1/RIP2 Signaling Pathway and Plays a Key Role in the Progression of Severe Acute Pancreatitis. Front Cell Infect Microbiol 2022; 12:838340. [PMID: 35811665 PMCID: PMC9257083 DOI: 10.3389/fcimb.2022.838340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 05/02/2022] [Indexed: 11/18/2022] Open
Abstract
Impaired intestinal barrier function and gut microbiota dysbiosis are believed to be related to exacerbation of acute pancreatitis (AP). As a bacterial cell wall peptidoglycan component, diaminopimelic acid (DAP) is a specific ligand of NOD1 that regulates the NOD1/RIP2/NF-kB signaling pathway. Here, we investigated the role of DAP in the crosstalk between the gut microbiota and pancreas during the occurrence of AP. Upregulation of NOD1/RIP2/NF-kB and elevated serum DAP levels were found in severe AP (SAP) model rats. The accumulation of DAP in SAP patients corroborated its ability to serve as an indicator of disease severity. Subsequently, SAP rats were treated with oral administration of the traditional Chinese medicine Qingyi Keli (QYKL) as well as neomycin, which can widely eliminate DAP-containing bacteria. Both QYKL and neomycin intervention ameliorated intestinal and pancreatic damage and systemic inflammation in SAP rats. Through 16S rDNA sequencing, we found that QYKL could rehabilitate the gut microbiota structure and selectively inhibit the overgrowth of enteric bacteria, such as Helicobacter and Lactobacillus, in SAP rats without affecting some protective strains, including Romboutsia and Allobaculum. Interestingly, we demonstrated that the decrease in serum DAP was accompanied by suppression of the NOD1/RIP2/NF-kB signaling pathway in both the intestine and pancreas of the two intervention groups. Taken together, these results suggested that the gut microbiota-DAP-NOD1/RIP2 signaling pathway might play a critical role in the progression of AP and that SAP could be alleviated via intervention in the signaling pathway. Our work provides new potential early warning indicators of SAP and targets for intervention.
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Affiliation(s)
- Juying Jiao
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- College of Integrative Medicine, Dalian Medical University, Dalian, China
- Shanghai Medical College, Fudan University, Shanghai, China
| | - Jianjun Liu
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- College of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Qi Li
- Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
| | - Guixin Zhang
- Pancreaticobiliary Centre, Department of General Surgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Chen Pan
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- College of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Fei Luo
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- College of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Qingkai Zhang
- Pancreaticobiliary Centre, Department of General Surgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Bing Qi
- Pancreaticobiliary Centre, Department of General Surgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Liang Zhao
- Pancreaticobiliary Centre, Department of General Surgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Peiyuan Yin
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- College of Integrative Medicine, Dalian Medical University, Dalian, China
- *Correspondence: Dong Shang, ; Peiyuan Yin,
| | - Dong Shang
- Clinical Laboratory of Integrative Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- College of Integrative Medicine, Dalian Medical University, Dalian, China
- Pancreaticobiliary Centre, Department of General Surgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- *Correspondence: Dong Shang, ; Peiyuan Yin,
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17
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Stenholm Å, Hedeland M, Pettersson CE. Neomycin removal using the white rot fungus Trametes versicolor. J Environ Sci Health A Tox Hazard Subst Environ Eng 2022; 57:436-447. [PMID: 35583106 DOI: 10.1080/10934529.2022.2072644] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 04/25/2022] [Accepted: 04/26/2022] [Indexed: 06/15/2023]
Abstract
The presence of antibiotic resistance genes in wastewater treatment plants (WWTPs), and in river and lake recipients show the need to develop new antibiotic removal strategies. The aminoglycoside antibiotic class is of special concern since the chemical structure of these compounds limits the choices of removal technologies. The experimental design included fungal mediated in vivo and in vitro experiments. The experiments were performed in Erlenmeyer flasks under non-sterile conditions. In the study, the role of the laccase redox mediator 4-hydroxy benzoic acid (HBA) in the removal of neomycin was investigated. The specific objective of the study was to conclude whether it is possible to use the white rot fungus (WRF) Trametes versicolor to biodegrade neomycin. It was shown that it is feasible to remove 34% neomycin in vitro (excluding living fungal cells) by laccase-HBA mediated extracellular biodegradation. In the in vivo experiments, polyurethane foam (PUF) was used as supporting material to immobilize fungal mycelia on. The presence of living fungal cells facilitated a removal of approximately 80% neomycin in the absence of HBA. Using liquid chromatography-high resolution-mass spectrometry, it was possible to tentatively identify oxidation products of neomycin hydrolysates. The results in this study open up the possibility to implement a pretreatment plant (PTP) aimed for neomycin removal.
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Affiliation(s)
- Åke Stenholm
- Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
- Cytiva AB, Uppsala, Sweden
| | - Mikael Hedeland
- Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
| | - Curt E Pettersson
- Department of Medicinal Chemistry, Analytical Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
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Zhou J, Ping R, Wu H, Liu H, Wang X, Ren A, Tian S, Ma Y. Recycling of neomycin fermentation residue using SEA-CBS technology: Growth performance and antibiotic resistance genes. Sci Total Environ 2022; 807:150860. [PMID: 34626630 DOI: 10.1016/j.scitotenv.2021.150860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 10/02/2021] [Accepted: 10/03/2021] [Indexed: 06/13/2023]
Abstract
Antibiotic fermentation residue (AFR) is a form of bioavailable matter, that represents a typical category of hazardous waste associated with drug production in China. The disposal of these residues seriously restricts the sustainable development of the pharmaceutical industry. In this study, the steam explosion and aerobic composting (SEA-CBS) system was developed to thoroughly convert neomycin fermentation residue to organic fertilizer. The results implied that the ultimate removal rate of antibiotics was as high as 99.9% in all cases, including macrolide (kitasamycin and spiramycin), lincosamide (lincomycin), and beta-lactam (cephalosporin and penicillin) antibiotic biowastes. Pot experiments were also conducted to study the attenuation rule of antibiotic residues in the soil, and the distribution of antibiotic resistant genes from trace antibiotics. The produced fertilizer presented the better performance on mustard growth than conventional fertilizers. The average plant height and biomass were increased by 14.33%-55.83% and 136.71%-326.83%, respectively, after SEA-CBS pretreatment. Moreover, neomycin was the primary selective pressure, and six antibiotic resistance genes (ARGs) correlated with neomycin were screened. The acc(6')ib gene was identified as the target ARGs, the main resistance mechanism was antibiotic inactivation, and the absolute and relative abundances were 1.06 × 105 ± 3.80 × 104 copies/g and 6.23 × 10-4 ± 1.75 × 10-4 copies/16 s in the NFR-amended soils. The microbial community analysis showed that the variation of the soil microbial community was not dominated by neomycin fermentation residue (NFR) at initial concentrations below 0.42 μg/kg soil. This work demonstrated that the SEA-CBS system not only functioned as an efficient technology for concurrent neomycin sulfate removal and NFR composting, but also applied to a wide range of other antibiotic bio-wastes, which may benefit the recycling of AFR, as well as the data provide a theoretical basis for future agricultural utilization and safe evaluation.
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Affiliation(s)
- Jieya Zhou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050080, China
| | - Ran Ping
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050080, China
| | - Hao Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Hongbo Liu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Xuming Wang
- Beijing Agro-biotechnology Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China
| | - AiLing Ren
- School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050080, China
| | - Shulei Tian
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Yingqun Ma
- School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an, Shanxi 710049, China.
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Sonousi A, Vasella A, Crich D. Synthesis of a Pseudodisaccharide Suitable for Synthesis of Ring I Modified 4,5-2-Deoxystreptamine Type Aminoglycoside Antibiotics. J Org Chem 2020; 85:7583-7587. [PMID: 32336094 PMCID: PMC7275914 DOI: 10.1021/acs.joc.0c00743] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
To facilitate the synthesis of paromomycin and/or neomycin analogues, we describe a cleavage of ring I from paromomycin that proceeds in the presence of azides and affords a glycosyl acceptor for the installation of a modified ring I. A paromomycin 4',6'-diol is oxidized by the Dess-Martin periodinane followed by m-chloroperoxybenzoic acid. Base treatment then affords a protected pseudodisaccharide, which functions as a glycosyl acceptor. The method should also apply to the cleavage of pyranosyl 4,6-diols from oligosaccharides and glycoconjugates.
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Affiliation(s)
- Amr Sonousi
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Andrea Vasella
- Organic Chemistry Laboratory, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093 Zürich, Switzerland
| | - David Crich
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, Georgia 30602, United States
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, United States
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, Georgia 30602, United States
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de Lastours V, Poirel L, Huttner B, Harbarth S, Denamur E, Nordmann P. Emergence of colistin-resistant Gram-negative Enterobacterales in the gut of patients receiving oral colistin and neomycin decontamination. J Infect 2020; 80:578-606. [PMID: 31954100 DOI: 10.1016/j.jinf.2020.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 01/03/2020] [Accepted: 01/08/2020] [Indexed: 11/17/2022]
Affiliation(s)
- Victoire de Lastours
- Université de Paris, IAME, INSERM, UMR 1137, F-75018 Paris, France; Service de médecine interne, Hôpital Beaujon, AP-HP, F-92210 Clichy, France.
| | - Laurent Poirel
- Université de Paris, IAME, INSERM, UMR 1137, F-75018 Paris, France; Swiss National Reference Center for Emerging Antibiotic Resistance (NARA), University of Fribourg, Fribourg, Switzerland; Emerging Antibiotic Resistance Unit, Medical and Molecular Microbiology, Department of Medicine, Faculty of Science and Medicine, Laboratoire Européen Associé « Emerging Antibiotic Resistance in Gram-negative bacteria », INSERM, University of Fribourg, Fribourg, Switzerland
| | - Benedikt Huttner
- Infection Control Program and WHO Collaborating Center, Geneva University Hospitals, Geneva, Switzerland; Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Stephan Harbarth
- Infection Control Program and WHO Collaborating Center, Geneva University Hospitals, Geneva, Switzerland; Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Erick Denamur
- Université de Paris, IAME, INSERM, UMR 1137, F-75018 Paris, France; Laboratoire de Génétique Moléculaire, Hôpital Bichat, AP-HP, F-75018 Paris, France
| | - Patrice Nordmann
- Université de Paris, IAME, INSERM, UMR 1137, F-75018 Paris, France; Swiss National Reference Center for Emerging Antibiotic Resistance (NARA), University of Fribourg, Fribourg, Switzerland; Emerging Antibiotic Resistance Unit, Medical and Molecular Microbiology, Department of Medicine, Faculty of Science and Medicine, Laboratoire Européen Associé « Emerging Antibiotic Resistance in Gram-negative bacteria », INSERM, University of Fribourg, Fribourg, Switzerland
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Harmancı C, Büyükgüzel K, Büyükgüzel E. The Effect of Neomycin on Survival and Development of Pimpla turionellae L. (Hymenoptera: Ichneumonidae) Reared on a Natural Host. J Econ Entomol 2019; 112:1081-1088. [PMID: 30649421 DOI: 10.1093/jee/toy419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 11/12/2018] [Indexed: 06/09/2023]
Abstract
Understanding the effects of diet on metabolic events is crucial for biological control programs of parasitoid insects. As bioindicators of long-term physiological stress: survivorship of fifth instar larvae, pupation, adult survival, and developmental time for stages of endoparasitoid Pimpla turionellae L. (Hymenoptera: Ichneumonidae) were investigated by rearing the parasitoid on the host, Galleria mellonella L. (Lepidoptera: Pyralidae) pupae were treated with neomycin. First instar larvae of G. mellonella were reared on artificial diets containing 0.005, 0.01, or 0.5 g neomycin (g/100 g of diet) until seventh instar larvae; the pupae from these larvae were used as a host for rearing P. turionellae. In the control group, the pupae from larvae reared on artificial diets without neomycin were used as a host. Survivorship of fifth instar, pupal, and adult stages of P. turionellae L. reared on G. mellonella pupae as a host fed with different concentrations of neomycin were significantly decreased in comparison to the control group. Approximately eighty percent of P. turionellae L. pupae were produced from control host pupae, while other neomycin concentrations significantly decreased the pupation of the parasitoid. Pimpla turionellae L. larvae reared on control host pupae reached fifth instar in about 9.6 ± 0.61 d, while the larvae reared from a host pupae exposed to the highest antibiotic concentration completed their development to the fifth instar in about 7.4 d. These results showed that neomycin, and possibly its metabolites, contaminated P. turionellae L. larvae from a host and affected larval stages of the parasitoid.
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Affiliation(s)
- Cumhur Harmancı
- Molecular Biology and Genetics Department, Zonguldak Bülent Ecevit University, Zonguldak, Turkey
| | - Kemal Büyükgüzel
- Biology Department, Zonguldak Bülent Ecevit University, Zonguldak, Turkey
| | - Ender Büyükgüzel
- Molecular Biology and Genetics Department, Zonguldak Bülent Ecevit University, Zonguldak, Turkey
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Krepl M, Vögele J, Kruse H, Duchardt-Ferner E, Wöhnert J, Sponer J. An intricate balance of hydrogen bonding, ion atmosphere and dynamics facilitates a seamless uracil to cytosine substitution in the U-turn of the neomycin-sensing riboswitch. Nucleic Acids Res 2018; 46:6528-6543. [PMID: 29893898 PMCID: PMC6061696 DOI: 10.1093/nar/gky490] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 05/23/2018] [Indexed: 01/04/2023] Open
Abstract
The neomycin sensing riboswitch is the smallest biologically functional RNA riboswitch, forming a hairpin capped with a U-turn loop-a well-known RNA motif containing a conserved uracil. It was shown previously that a U→C substitution of the eponymous conserved uracil does not alter the riboswitch structure due to C protonation at N3. Furthermore, cytosine is evolutionary permitted to replace uracil in other U-turns. Here, we use molecular dynamics simulations to study the molecular basis of this substitution in the neomycin sensing riboswitch and show that a structure-stabilizing monovalent cation-binding site in the wild-type RNA is the main reason for its negligible structural effect. We then use NMR spectroscopy to confirm the existence of this cation-binding site and to demonstrate its effects on RNA stability. Lastly, using quantum chemical calculations, we show that the cation-binding site is altering the electronic environment of the wild-type U-turn so that it is more similar to the cytosine mutant. The study reveals an amazingly complex and delicate interplay between various energy contributions shaping up the 3D structure and evolution of nucleic acids.
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Affiliation(s)
- Miroslav Krepl
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Jennifer Vögele
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Holger Kruse
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Elke Duchardt-Ferner
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Jens Wöhnert
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Jiri Sponer
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic
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Smith JP, Kasten-Jolly J, Rebellato L, Haisch CE, Thomas JM. Use of Allogeneic Bone Marrow Labeled with Neomycin Resistance Gene to Examine Bone Marrow-Derived Chimerism in Experimental Organ Transplantation. Cell Transplant 2017; 6:369-76. [PMID: 9258510 DOI: 10.1177/096368979700600403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Posttransplant infusion of viable donor bone marrow cells (DBMC) has been shown in our previous studies to promote acceptance of incompatible kidney allografts in rhesus monkeys after treatment with polyclonal antithymocyte globulin to deplete peripheral T-lymphocytes. In this nonhuman primate model, the infusion of the DBMC is requisite for the induction of functional graft tolerance and specific MLR and CTLp unresponsiveness, although the relevant role and fate of bone marrow-derived chimeric cells is uncertain. Standard immunological and molecular techniques applied to this monkey model are unable to differentiate between chimeric cells derived from the infused DBMC and those derived from allograft-borne passenger leukocyte emigrants. To distinguish chimerism due to infused DBMC, we transduced DBMC with a functional neomycin resistance gene (Neor) using the retroviral vector pHSG-Neo. Neor-Mransduced BMC were infused into recipients approximately 2 wk after kidney transplantation and treatment with rabbit antithymocyte globulin. No maintenance immunosuppressive drugs were given. Genomic DNA isolated from peripheral blood leukocytes was used to monitor the presence of Neor-positive cells. Tissue samples obtained at necropsy also were assessed for Neor-positive chimeric cells. The presence of DBMC-derived chimerism was assessed by polymerase chain reaction using Neor sequence-specific primers (PCR-SSP). Chimerism was detectable in recipient tissues at various times for up to 6 mo after DBMC infusion. These studies using gene transduction methodology indicate that a stable genetic marker can provide capability to examine DBMC-derived chimerism for prolonged periods in a nonhuman primate model. This approach should facilitate future studies in preclinical models to study the role and type of chimeric cell lineages in relation to functional allograft tolerance.
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Affiliation(s)
- J P Smith
- Department of Anatomy, East Carolina University, Greenville, NC, USA
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Affiliation(s)
- Geoffrey Michael Gadd
- Geomicrobiology Group, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK
- Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China
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Chang J, Choi J, Rah YC, Yoo MH, Oh KH, Im GJ, Lee SH, Kwon SY, Park HC, Chae SW, Jung HH. Sodium Selenite Acts as an Otoprotectant against Neomycin-Induced Hair Cell Damage in a Zebrafish Model. PLoS One 2016; 11:e0151557. [PMID: 26974429 PMCID: PMC4790947 DOI: 10.1371/journal.pone.0151557] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 03/01/2016] [Indexed: 01/13/2023] Open
Abstract
Sodium selenite is a trace element essential for many physiological functions in the body. It is involved in various biological processes; it acts as a cofactor for antioxidant enzymes that protect against free radicals and is reported to limit metal-mediated oxidative DNA damage. In the present study, we investigated the effect of sodium selenite on neomycin ototoxicity in wild-type and transgenic zebrafish (Brn3C: EGFP). Five or six days post-fertilization, zebrafish larvae were co-exposed to 125 μM neomycin and various concentrations (10 μM, 100 μM, 250 μM, and 500 μM) of sodium selenite for 1 h. Hair cells within neuromasts of the supraorbital (SO1 and SO2), otic (O1), and occipital (OC1) lateral lines were analyzed by fluorescence microscopy (n = 10 fish per treatment). Hair cell survival was estimated as the ratio of the hair cell numbers in each group compared to those of the control group that were not exposed to neomycin. Apoptosis and hair cell damage of neuromasts were evaluated using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) assay and 2-[4-(dimethylamino) styryl]-N-ethylpyridinium iodide (DASPEI) assay, respectively. Ultrastructural changes were evaluated using scanning electron microscopy and transmission electron microscopy. Neuromast hair cells were preserved in zebrafish exposed to 125 μM neomycin and 500 μM sodium selenite for 1 h. Sodium selenite protected against neomycin-induced hair cell loss of neuromasts, reduced apoptosis, and prevented zebrafish ultrastructural changes. We propose that sodium selenite protects against neomycin-induced hair cell damage by inhibiting apoptosis, decreasing the disarray of stereocilia, and preventing ultrastructural changes in the neuromast hair cells of the zebrafish.
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Affiliation(s)
- Jiwon Chang
- Department of Otorhinolaryngology-Head and Neck Surgery, Hallym University College of Medicine, Seoul, Korea
| | - June Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
- * E-mail:
| | - Yoon Chan Rah
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Myung Hoon Yoo
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Kyoung Ho Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Gi Jung Im
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Seung Hoon Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Soon Young Kwon
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Hae-Chul Park
- Laboratory of Neurodevelopmental Genetics, Graduate School of Medicine, Korea University, Seoul, Korea
| | - Sung Won Chae
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Hak Hyun Jung
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
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Abstract
BACKGROUND Mutations in Zinc Finger Protein of the Cerebellum 3 (ZIC3) cause X-linked heterotaxy and isolated cardiovascular malformations. Recent data suggest a potential cell-autonomous role for Zic3 in myocardium via regulation of Nppa and Tbx5. We sought to develop a hypomorphic Zic3 mouse to model human heterotaxy and investigate developmental mechanisms underlying variability in cardiac phenotypes. METHODS Zic3 hypomorphic mice were created by targeted insertion of a neomycin cassette and investigated by gross, histologic, and molecular methods. RESULTS Low-level Zic3 expression is sufficient for partial rescue of viability as compared with Zic3 null mice. Concordance of early left-right molecular marker abnormalities and later anatomic abnormalities suggests that the primary effect of Zic3 in heart development occurs during left-right patterning. Cardiac-specific gene expression of Nppa (atrial natriuretic factor) and Tbx5 marked the proper morphological locations in the heart regardless of looping abnormalities. CONCLUSION Zic3 hypomorphic mice are useful models to investigate the variable cardiac defects resulting from a single genetic defect. Low-level Zic3 expression rescues the left pulmonary isomerism identified in Zic3 null embryos. Our data do not support a direct role for Zic3 in the myocardium via regulation of Nppa and Tbx5 and suggest that the primary effect of Zic3 on cardiac development occurs during left-right patterning.
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Affiliation(s)
- Allison M. Haaning
- Cincinnati Children’s Hospital Medical Center, Division of Molecular Cardiovascular Biology, Cincinnati, OH
| | - Malgorzata E. Quinn
- Cincinnati Children’s Hospital Medical Center, Division of Molecular Cardiovascular Biology, Cincinnati, OH
| | - Stephanie M. Ware
- Cincinnati Children’s Hospital Medical Center, Division of Molecular Cardiovascular Biology, Cincinnati, OH
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McGarry GW. Recurrent epistaxis in children. BMJ Clin Evid 2013; 2013:0311. [PMID: 24172703 PMCID: PMC3812896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
INTRODUCTION Up to 9% of children may have recurrent nosebleeds, usually originating from the anterior septum, but the majority grow out of the problem. METHODS AND OUTCOMES We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for recurrent idiopathic epistaxis in children? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2013 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). RESULTS We found 5 systematic reviews or RCTs that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. CONCLUSIONS In this systematic review we present information relating to the effectiveness and safety of the following interventions: antiseptic cream (containing chlorhexidine hydrochloride, neomycin sulfate, or both), petroleum jelly, and silver nitrate cautery.
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An L, Yuan Y, Yu B, Yang T, Cheng Y. [Cloning goat producing human lactoferrin with genetically modified donor cells selected by single or dual markers]. Sheng Wu Gong Cheng Xue Bao 2012; 28:1482-1491. [PMID: 23593872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We compared the efficiency of cloning goat using human lactoferrin (hLF) with genetically modified donor cells marked by single (Neo(r)) or double (Neo(r)/GFP) markers. Single marker expression vector (pBLC14) or dual markers expression vector (pAPLM) was delivered to goat fetal fibroblasts (GFF), and then the transgenic GFF was used as donor cells to produce transgenic goats. Respectively, 58.8% (20/34) and 86.7% (26/30) resistant cell lines confirmed the transgenic integration by PCR. Moreover, pAPLM cells lines were subcultured with several passages, only 20% (6/30) cell lines was observed fluorescence from each cell during the cell passage. Somatic cell nuclear transfer using the donor cells harbouring pBLC14 or pAPLM construct, resulting in a total of 806 reconstructed embryos, a pregnancy rate at 35 d (53.8%, 39.1%) and 60 d (26.9%, 21.7%), and an offspring birth rate (1.9%, 1.4%) with 5 and 7 newborn cloned goats, respectively. Transgene was confirmed by PCR and southern-blot in all cloned offspring. There were no significant differences at the reconstructed embryo fusion rates, pregnancy rates and the birth rate (P > 0.05) between single and double markers groups. The Neo(r)/GFP double markers could improve the reliability for accurately and efficiently selecting the genetically modified donor cells. No adverse effect was observed on the efficiency of transgenic goat production by SCNT using somatic cells transfected with double (Neo(r)/GFP) markers vector.
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Affiliation(s)
- Liyou An
- College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, Jiangsu, China
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Vekhova E, Ivashkin EG, Yurchenko O, Chaban A, Dyachuk VA, Khabarova MY, Voronezhskaya EE. Modulation of Mytilus trossulus (Bivalvia: Mollusca) larval survival and growth in culture. Short communication. Acta Biol Hung 2012; 63 Suppl 2:230-4. [PMID: 22776499 DOI: 10.1556/abiol.63.2012.suppl.2.31] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Commercial importance and ability to live in a wide range of salinities have made the common mussel, Mytilus trossulus, a relevant model to study modulation of larval growth and development. We investigated the effects of various salinities combined with neomycin and ampicillin application on Mytilus larvae survival and growth. Both neomycin and ampicillin enhanced trochophore and veliger survival under condition of low salinity. The average veliger size was increasing in accordance with the increase of salinity. In case of neomycin treatment 3.6% of the larvae reached the pediveliger stage. No abnormalities of larval morphology of the FMRFamide and 5-HT systems occurred after 7 days of culturing with both antibiotics.
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Affiliation(s)
- Evgenia Vekhova
- A. V. Zhirmunsky Institute of Marine Biology, Far Eastern Branch of Russian Academy of Sciences, 690059 Vladivostok, Russia
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Machovcova A. The frequency of contact allergy in children and adolescents in the Czech Republic. Acta Dermatovenerol Croat 2012; 20:75-79. [PMID: 22726278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The objective of our study was to determine the prevalence of contact hypersensitivity in asymptomatic Czech schoolchildren. We recruited 236 Prague asymptomatic schoolchildren for epicutaneous tests. The children were tested with European baseline series (25 allergens). A total of 218 children (114 boys and 104 girls) completed the study. Of these, 67 (30.7%) children had one or more positive reactions to tested allergens. Nickel, neomycin and potassium dichromate were the most prevalent allergens detected in our study. Our findings may support the notion that allergic contact sensitization in children is not so rare and children, especially those with chronic dermatitis, should be patch tested regularly.
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Affiliation(s)
- Alena Machovcova
- Department of Dermatology, Faculty Hospital, Motol 150 06, Prague 5, Czech Republic.
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PETTERSSON T, KLEMOLA E, WAGER O. Treatment of Acute Gases of Salmonella Infection and Salmonella Carriers with Ampicillin and Neomycin. ACTA ACUST UNITED AC 2009; 175:185-90. [PMID: 14124633 DOI: 10.1111/j.0954-6820.1964.tb00565.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nourski KV, Abbas PJ, Miller CA, Robinson BK, Jeng FC. Acoustic-electric interactions in the guinea pig auditory nerve: simultaneous and forward masking of the electrically evoked compound action potential. Hear Res 2007; 232:87-103. [PMID: 17723284 PMCID: PMC2048988 DOI: 10.1016/j.heares.2007.07.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 06/29/2007] [Accepted: 07/03/2007] [Indexed: 11/27/2022]
Abstract
The study investigated the time course of the effects of acoustic and electric stimulation on the electrically evoked compound action potential (ECAP). Adult guinea pigs were used in acute experimental sessions. Bursts of acoustic noise and high-rate (5000 pulses/s) electric pulse trains were used as maskers. Biphasic electric pulses were used as probes. ECAPs were recorded from the auditory nerve trunk. Simultaneous masking of the ECAP with acoustic noise featured an onset effect and a decrease in the amount of masking to a steady state. It was characterized by a two-component exponential function. The amount of masking increased with masker level and decreased with probe level. Post-stimulatory ECAP recovery often featured a non-monotonic time course, described by a three-component exponent. Electric maskers produced similar post-stimulatory effects in hearing and acutely deafened subjects. Acoustic stimulation affects the ECAP in a level- and time-dependent manner. Simultaneous masking follows a time course comparable to that of adaptation to an acoustic stimulus. Refractoriness, spontaneous activity, and adaptation are suggested to play a role in ECAP recovery. Post-stimulatory changes in synchrony, possibly due to recovery of spontaneous activity and an additional hair-cell independent mechanism, are hypothesized to contribute to the observed non-monotonicity of recovery.
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Affiliation(s)
- Kirill V Nourski
- Department of Otolaryngology--Head and Neck Surgery, The University of Iowa, Iowa City, IA 52242, USA.
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Molostvov G, James S, Fletcher S, Bennett J, Lehnert H, Bland R, Zehnder D. Extracellular calcium-sensing receptor is functionally expressed in human artery. Am J Physiol Renal Physiol 2007; 293:F946-55. [PMID: 17537980 DOI: 10.1152/ajprenal.00474.2006] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Accelerated medial calcification is a major cause of premature cardiovascular mortality in patients with chronic kidney disease (CKD). Evidence suggests that extracellular concentration of Ca2+ and vascular smooth muscle cells may play a pivotal role in the pathogenesis of vascular calcification. The calcium-sensing receptor (CaSR) is a G protein-coupled receptor that is expressed in a range of tissues, but characterization of its expression and function in the cardiovascular system is limited. Here we report the expression of CaSR mRNA (RT-PCR) and protein (Western blotting and immunocytochemistry) in human aortic smooth muscle cells (HAoSMC). Treatment of HAoSMC with Ca2+ (0-5 mM; 0-30 min) or the CaSR agonists gentamycin and neomycin (0-300 microM; 0-30 min) resulted in a dose- and time-dependent phosphorylation of ERK1/2. Gentamycin- and neomycin-mediated ERK1/2 stimulation was inhibited by pretreatment with PD-98059, an ERK-activating kinase 1 (MEK1) inhibitor, confirming specificity of the observed effects. ERK1/2 activation was inhibited in HAoSMC, with CaSR expression knocked down by transfection with specific small-interference RNA, which confirmed that the observed neomycin/gentamycin-induced MEK1/ERK1/2 activation was mediated via the CaSR. CaSR mRNA and protein were also expressed in large and small arteries from normal subjects (kidney donors) and patients with end-stage renal disease (ESRD). The CaSR was detected in smooth muscle and endothelial cells. Expression was significantly lower in arteries from ESRD patients. In conclusion, these data not only demonstrate the presence of a functional CaSR in human artery but show a correlation between CaSR expression and progression of CKD.
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Affiliation(s)
- Guerman Molostvov
- Clinical Sciences Research Institute, University of Warwick, Coventry, UK
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RAHMAN SA, PURSER DB, TYZNIK WJ. Cultivation of Rumen Protozoa. I. Factors Influencing the Cultivation of Rumen Oligotrich Protozoa “In Vitro”. ACTA ACUST UNITED AC 2007; 11:51-5. [PMID: 14119561 DOI: 10.1111/j.1550-7408.1964.tb01720.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Leake PA, Hradek GT, Vollmer M, Rebscher SJ. Neurotrophic effects of GM1 ganglioside and electrical stimulation on cochlear spiral ganglion neurons in cats deafened as neonates. J Comp Neurol 2007; 501:837-53. [PMID: 17311311 PMCID: PMC2409118 DOI: 10.1002/cne.21275] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Previous studies have shown that electrical stimulation of the cochlea by a cochlear implant promotes increased survival of spiral ganglion (SG) neurons in animals deafened early in life (Leake et al. [1999] J Comp Neurol 412:543-562). However, electrical stimulation only partially prevents SG degeneration after deafening and other neurotrophic agents that may be used along with an implant are of great interest. GM1 ganglioside is a glycosphingolipid that has been reported to be beneficial in treating stroke, spinal cord injuries, and Alzheimer's disease. GM1 activates trkB signaling and potentiates neurotrophins, and exogenous administration of GM1 has been shown to reduce SG degeneration after hearing loss. In the present study, animals were deafened as neonates and received daily injections of GM1, beginning either at birth or after animals were deafened and continuing until the time of cochlear implantation. GM1-treated and deafened control groups were examined at 7-8 weeks of age; additional GM1 and no-GM1 deafened control groups received a cochlear implant at 7-8 weeks of age and at least 6 months of unilateral electrical stimulation. Electrical stimulation elicited a significant trophic effect in both the GM1 group and the no-GM1 group as compared to the contralateral, nonstimulated ears. The results also demonstrated a modest initial improvement in SG density with GM1 treatment, which was maintained by and additive with the trophic effect of subsequent electrical stimulation. However, in the deafened ears contralateral to the implant SG soma size was severely reduced several months after withdrawal of GM1 in the absence of electrical activation.
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Affiliation(s)
- Patricia A Leake
- Epstein Hearing Research Laboratory, Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, California 94143-0526, USA.
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Abstract
Perlecan knock-in mice were developed to model Schwartz-Jampel syndrome (SJS), a skeletal disease resulting from decreased perlecan. Two mouse strains were generated: those carrying a C-to-Y mutation at residue 1532 and the neomycin cassette (C1532Yneo) and those harboring the mutation alone (C1532Y). Immunostaining, biochemistry, size measurements, skeletal studies and histology revealed Hspg2 transcriptional changes in C1532Yneo mice, leading to reduced perlecan secretion and a skeletal disease phenotype characteristic of SJS patients. Skeletal disease features include smaller size, impaired mineralization, misshapen bones, flat face and joint dysplasias reminiscent of osteoarthritis and osteonecrosis. Moreover, C1532Yneo mice displayed transient expansion of hypertrophic cartilage in the growth plate concomitant with radial trabecular bone orientation. In contrast, C1532Y mice, harboring only the mutation associated with SJS, displayed a mild phenotype, inconsistent with SJS. These studies question the C1532Y mutation as the sole causative factor of SJS in the human family harboring this alteration and imply that transcriptional changes leading to perlecan reduction may represent the disease mechanism for SJS.
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Affiliation(s)
- Kathryn D Rodgers
- Department of Animal Biology, University of Pennsylvania School of Veterinary Medicine, 3800 Spruce Street, Rosenthal Room 152, Pennsylvania, PA 19104-6046, USA.
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Abstract
CONCLUSION Our data show that temporary appearance of atypical type 1 neurons, like type 3 neurons, might be another degenerating form of spiral ganglion neurons (SGNs); peripherin might be a marker of degenerating neurons. OBJECTIVES Further morphological and biochemical studies on surviving SGNs after loss of hair cells might offer clues for preventing their degeneration. MATERIALS AND METHODS We observed the ultrastructural features of surviving SGNs and analyzed the peripherin immunoreactivity at 4, 10, or 20 weeks after systemic injection of neomycin in rats. RESULTS Type 3 neurons, similar to type 1 neurons but unmyelinated, appeared in the spiral ganglion by 4-week survival, and showed a survival advantage in remaining SGNs by longer surviving periods. We observed neurons packed with dense intermediate filament and with multiple layers of dense myelin sheath (atypical type 1 neurons) in the degenerating neurons. Atypical type 1 neurons were observed among the degenerating neurons in the 4- and 10-week survival groups, but disappeared in longer surviving animals. By means of immunohistochemistry, only smaller SGNs of normal rats were strongly stained by anti-peripherin antibody, whereas increased immunoreactivity was observed in both large and small remaining neurons after neomycin treatment, especially in 10- and 20-week survival animals.
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Affiliation(s)
- Yucheng Wang
- Otology Skull Base Surgery Department, Hearing Research Institute, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai
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Ye J, Chen Q, Zhou J, Li L. Cloned Vero cell lines transfected with full-length A-segment or ORF1 cDNA sequence of IBDV. Cell Biol Int 2006; 31:165-72. [PMID: 17137796 DOI: 10.1016/j.cellbi.2006.09.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2006] [Revised: 08/24/2006] [Accepted: 09/26/2006] [Indexed: 11/27/2022]
Abstract
Recombinant plasmids containing the A-segment or VP2/4/3 gene of infectious bursal disease virus (IBDV) were transfected into Vero cells. Monoclonal Vero cell lines were generated under G418 selection. Genomic (PCR/Southern blot) and transcriptional (RT-PCR/Northern blot) analyses showed that one copy of A-segment or VP2/4/3 or a partial gene of them was randomly and stably inserted into genomic DNA of Vero cells, and was able to transcribe corresponding mRNA. IFA/IPMA and Western blot analyses further confirmed that two of the monoclonal Vero cells with insertion of the A-segment of IBDV into genomic DNA could stably express VP2, VP3 and VP5 proteins, one cell line only expressed VP2 protein, and three monoclonal Vero cell lines with genomic insertion of the VP2/4/3 gene of IBDV could express VP2, VP3 and VP4 proteins. Under G418 selection, integrated foreign genes can be inherited along with cellular genomic DNA during cell replications. Moreover, DNA fragmentation and caspase-3 activity assays illustrated that cell apoptosis did not develop in monoclonal Vero cell lines expressing VP2 and VP5 proteins. The monoclonal IBDV gene-inserted Vero cell lines developed in this study will facilitate better understanding of IBDV and other members of the Birnaviridae in an expression system that would enable investigation of virus-host cell interactions on the cellular and molecular level.
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Affiliation(s)
- Juxiu Ye
- Laboratory of Virology and Immunology, Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, 268 Kaixuan Road, Hangzhou, Zhejiang 310029, PR China
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Murphy BR, Moayedpardazi HS, Gewirtz AM, Diamond SL, Pierce EA. Delivery and mechanistic considerations for the production of knock-in mice by single-stranded oligonucleotide gene targeting. Gene Ther 2006; 14:304-15. [PMID: 17024103 DOI: 10.1038/sj.gt.3302866] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Single-stranded oligodeoxynucleotide (ssODN) gene targeting may facilitate animal model creation and gene repair therapy. Lipofection of ssODN can introduce point mutations into target genes. However, typical efficiencies in mouse embryonic stem cells (ESC) are <10(-4), leaving corrections too rare to effectively identify. We developed ESC lines with an integrated mutant neomycin resistance gene (Tyr22Ter). After targeting with ssODN, repaired cells survive selection in G418. Correction efficiencies varied with different lipofection procedures, clonal lines, and ssODN designs, ranging from 1 to 100 corrections per million cells plated. Uptake studies using cell sorting of Cy5-labelled ssODN showed 40% of the corrections concentrated in the best transfected 22% of cells. Four different basepair mismatches were tested and results show that the base-specificity of the mismatch is critical. Dual mismatch ssODN also showed mismatch preferences. These ESC lines may facilitate development of improved ssODN targeting technologies for either animal production or ex vivo gene therapy.
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Affiliation(s)
- B R Murphy
- Department of Chemical and Biomolecular Engineering, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA, USA
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Yakisich JS, Sandoval PY, Morrison TL, Kapler GM. TIF1 activates the intra-S-phase checkpoint response in the diploid micronucleus and amitotic polyploid macronucleus of Tetrahymena. Mol Biol Cell 2006; 17:5185-97. [PMID: 17005912 PMCID: PMC1679683 DOI: 10.1091/mbc.e06-05-0469] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The ribosomal DNA origin binding protein Tif1p regulates the timing of rDNA replication and is required globally for proper S-phase progression and division of the Tetrahymena thermophila macronucleus. Here, we show that Tif1p safeguards chromosomes from DNA damage in the mitotic micronucleus and amitotic macronucleus. TIF1p localization is dynamically regulated as it moves into the micro- and macronucleus during the respective S phases. TIF1 disruption mutants are hypersensitive to hydroxyurea and methylmethanesulfonate, inducers of DNA damage and intra-S-phase checkpoint arrest in all examined eukaryotes. TIF1 mutants incur double-strand breaks in the absence of exogenous genotoxic stress, destabilizing all five micronuclear chromosomes. Wild-type Tetrahymena elicits an intra-S-phase checkpoint response that is induced by hydroxyurea and suppressed by caffeine, an inhibitor of the apical checkpoint kinase ATR/MEC1. In contrast, hydroxyurea-challenged TIF1 mutants fail to arrest in S phase or exhibit caffeine-sensitive Rad51 overexpression, indicating the involvement of TIF1 in checkpoint activation. Although aberrant micro- and macronuclear division occurs in TIF1 mutants and caffeine-treated wild-type cells, TIF1p bears no similarity to ATR or its substrates. We propose that TIF1 and ATR function in the same epistatic pathway to regulate checkpoint responses in the diploid mitotic micronucleus and polyploid amitotic macronucleus.
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Affiliation(s)
- J. Sebastian Yakisich
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114
| | - Pamela Y. Sandoval
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114
| | - Tara L. Morrison
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114
| | - Geoffrey M. Kapler
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114
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Liepinsh DJ, Grivennikov SI, Klarmann KD, Lagarkova MA, Drutskaya MS, Lockett SJ, Tessarollo L, McAuliffe M, Keller JR, Kuprash DV, Nedospasov SA. Novel lymphotoxin alpha (LTalpha) knockout mice with unperturbed tumor necrosis factor expression: reassessing LTalpha biological functions. Mol Cell Biol 2006; 26:4214-25. [PMID: 16705172 PMCID: PMC1489085 DOI: 10.1128/mcb.01751-05] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Revised: 11/04/2005] [Accepted: 01/03/2006] [Indexed: 11/20/2022] Open
Abstract
Lymphotoxin alpha (LTalpha) can exist in soluble form and exert tumor necrosis factor (TNF)-like activity through TNF receptors. Based on the phenotypes of knockout (KO) mice, the physiological functions of LTalpha and TNF are considered partly redundant, in particular, in supporting the microarchitecture of the spleen and in host defense. We exploited Cre-LoxP technology to generate a novel neomycin resistance gene (neo) cassette-free LTalpha-deficient mouse strain (neo-free LTalpha KO [LTalphaDelta/Delta]). Unlike the "conventional" LTalpha-/- mice, new LTalphaDelta/Delta animals were capable of producing normal levels of systemic TNF upon lipopolysaccharide (LPS) challenge and were susceptible to LPS/D-galactosamine (D-GalN) toxicity. Activated neutrophils, monocytes, and macrophages from LTalphaDelta/Delta mice expressed TNF normally at both the mRNA and protein levels as opposed to conventional LTalpha KO mice, which showed substantial decreases in TNF. Additionally, the spleens of the neo-free LTalpha KO mice displayed several features resembling those of LTbeta KO mice rather than conventional LTalpha KO animals. The phenotype of the new LTalphaDelta/Delta mice indicates that LTalpha plays a smaller role in lymphoid organ maintenance than previously thought and has no direct role in the regulation of TNF expression.
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Affiliation(s)
- Dmitry J Liepinsh
- Basic Research Program, SAIC-Frederick, Inc., NCI--Frederick, Frederick, Maryland 21702, USA
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Affiliation(s)
- S A Waksman
- Department of Microbiology, New Jersey Agricultural Experiment Station, Rutgers University, New Brunswick, N. J
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Affiliation(s)
- S A Waksman
- Department of Microbiology, New Jersey Agricultural Experiment Station, New Brunswick, New Jersey
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Bradshaw SE, Shankar P, Maini R. Topical steroid and antibiotic combination therapy in red eye conditions. Br J Gen Pract 2006; 56:304. [PMID: 16611527 PMCID: PMC1832246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023] Open
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