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Review: Defense responses in sweetpotato (Ipomoea batatas L.) against biotic stress. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 337:111893. [PMID: 37813194 DOI: 10.1016/j.plantsci.2023.111893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 10/03/2023] [Accepted: 10/06/2023] [Indexed: 10/11/2023]
Abstract
Sweetpotato (Ipomoea batatas L.) is regarded as amongst the world's most important crops for food, vegetable, forage, and raw material for starch and alcohol production. Since pest attack and disease infection are the main limiting aspects frequently causing the yield loss and quality degradation of sweetpotato, it is a great demand to develop the effective defense strategies for maintaining productivity. In the past decade, many studies have focused on dynamic analysis at the physiological, biochemical, and molecular responses of sweetpotatoes to environmental challenges. This review offers an overview of the defense mechanisms against biotic stresses in sweetpotato observed so far, particularly insect herbivory and pathogen infections. The defenses of sweetpotato include the regulation of the toxic and anti-digestive proteins, plant-derived compounds, physical barrier formation, and sugar distribution. Ipomoelin and sporamin have been extensively researched for the defense against herbivore wounding. Herbivory-induced plant volatiles, chlorogenic acid, and latex phytochemicals play important roles in defenses for insect herbivory. Induction of IbSWEET10 reduces sugar content to mediate F. oxysporum resistance. Therefore, these researches provide the genetic strategies for improving resistance bioengineering and breeding of sweetpotato crops and future prospects for research in this field.
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Regulatory roles of microRNA163 in responses to stresses in Arabidopsis. PHYSIOLOGIA PLANTARUM 2023; 175:e14053. [PMID: 37882263 DOI: 10.1111/ppl.14053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 10/07/2023] [Accepted: 10/09/2023] [Indexed: 10/27/2023]
Abstract
MicroRNAs (miRNAs) are small regulatory RNAs that participate in various biological processes by silencing target genes. In Arabidopsis, microRNA163 (miR163) was found to be involved in seed germination, root development, and biotic resistance. However, the regulatory roles of miR163 remain unclear. In the current study, the mir163 mutant was investigated to comprehensively understand and characterize its functions in Arabidopsis. RNA-sequencing and Gene Ontology enrichment analyses revealed that miR163 might be involved in "response to stimulus" and "metabolic process". Interestingly, "response to stress", including heat, cold, and oxidative stress, was enriched under the subcategory of "response to stimulus". We observed that miR163 and PXMT were repressed and induced under heat stress, respectively. Furthermore, the study detected significant differences in seed germination rate, hypocotyl length, and survival rate, indicating a variation in the thermotolerance between WT and mir163 mutant. The results revealed that the mir163 mutant had a lesser degree of germination inhibition by heat treatment than WT. In addition, the mir163 mutant showed a better survival rate and longer hypocotyl length under heat treatment than the WT. The metabolomes of WT and mir163 mutant were further analyzed. The contents of benzene derivatives and flavonoids were affected by miR163, which could enhance plants' defense abilities. In conclusion, miR163/targets regulated the expression of stress-responsive genes and the accumulation of defense-related metabolites to alter stress tolerance.
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Involvement of microRNA164 in responses to heat stress in Arabidopsis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 329:111598. [PMID: 36657663 DOI: 10.1016/j.plantsci.2023.111598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 12/28/2022] [Accepted: 01/14/2023] [Indexed: 06/17/2023]
Abstract
MicroRNAs (miRNAs) are considered to be integral parts of plant stress regulatory networks. Under long-term heat stress, miR164 is induced. Conversely, its targets are repressed. Transgenic overexpressors (164OE) and mutants of MIR164 (mir164) were used to study miR164's functions during heat responses. Target gene expression decreased in 164OE transgenic plants and increased in mir164a-4 and mir164b mutants. Under heat stress, the mir164 mutants presented heat-sensitive phenotypes, while 164OE transgenic plants showed better thermotolerance than wild-type (WT) plants. Overexpression of miR164 decreased heat-inhibition of hypocotyl lengths. Under heat stress, miR164 target genes modulated the expression of chlorophyll b reductase and chlorophyll catabolic genes, reducing the chlorophyll a/b ratio. More H2O2 accumulated in the mir164 mutants under heat stress, which may have caused oxidative damage. In addition, expression of HSPs was altered in the experimental plants compared to that of the WT. Overall, miR164 influenced target gene expression, altering development, chlorophyll a/b ratio, H2O2-caused damage, and HSPs expression under long-term heat stress. These phenomena, in turn, likely influence the thermotolerance of plants.
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[Spatiotemporal changes of COVID-19 outbreak in Shanghai]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2022; 43:1699-1704. [PMID: 36444450 DOI: 10.3760/cma.j.cn112338-20220608-00511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To clarify the epidemiological characteristics and spatiotemporal clustering dynamics of COVID-19 in Shanghai in 2022. Methods: The COVID-19 data presented on the official websites of Municipal Health Commissions of Shanghai during March 1, 2022 and May 31, 2022 were collected for a spatial autocorrelation analysis by GeoDa software. A logistic growth model was used to fit the epidemic situation and make a comparison with the actual infection situation. Results: Pudong district had the highest number of symptomatic and asymptomatic infectants, accounting for 29.30% and 35.58% of the total infectants. Differences in cumulative attack rates and infection rates among 16 districts (P<0.001) were significant. The rates were significantly higher in Huangpu district than in other districts. The attack rate of COVID-19 from March 1, 2022 to May 31, 2022 had a global spatial positive correlation (P<0.05). Spatial distribution of COVID-19 attack rate was different at different periods. The global autocorrelation coefficient from March 16 to March 29, April 6 to April 12 and May 18 to May 24 had no statistical significance (P>0.05). Our local autocorrelation analysis showed that 22 high-high clustering areas were detected in eight periods.The high-risk hot-spot areas have experienced a "less-more-less" change process. The growth model fitting results were consistent with the actual infection situation. Conclusion: There was a clear spatiotemporal correlation in the distribution of COVID-19 in Shanghai. The comprehensive prevention and control measures of COVID-19 epidemic in Shanghai have effectively prohibited the growth of the epidemic, not only curbing the spatially spread of high-risk epidemic areas, but also reducing the risk of transmission to other cities.
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IbTLD modulates reactive oxygen species scavenging and DNA protection to confer salinity stress tolerance in tobacco. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 323:111415. [PMID: 35963494 DOI: 10.1016/j.plantsci.2022.111415] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 08/02/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
Plants accumulate reactive oxygen species (ROS) that may damage the cells under prolonged stress conditions. Reduction of the excessive ROS production can alleviate oxidative damage and enhance the survival rates under stress. TLDc-containing protein (TLD) was reported to confer tolerance to oxidative stress, but the regulatory mechanism of TLD remains unclear. In this study, we ectopically overexpressed the Ipomoea batatas TLDc gene (IbTLD) in tobacco and characterized its functions. RNA-sequencing analysis and Gene Ontology term enrichment analysis revealed that IbTLD up-regulates auxin-responsive genes in response to oxidative stress. Under salinity stress, the IbTLD transgenic lines showed higher germination rates, chlorophyll contents, and root lengths than wild type (W38). In addition, the IbTLD transgenic lines showed higher expression of ROS scavenging genes, nudix hydrolases, ROS scavenging enzyme activity, and lesser DNA damage compared to W38 under salinity stress. Therefore, our results suggest that IbTLD activates the expression of ROS scavenging genes and confers tolerance to salinity stress in planta.
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Large-scale data analysis for robotic yeast one-hybrid platforms and multi-disciplinary studies using GateMultiplex. BMC Biol 2021; 19:214. [PMID: 34560855 PMCID: PMC8461970 DOI: 10.1186/s12915-021-01140-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 09/03/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Yeast one-hybrid (Y1H) is a common technique for identifying DNA-protein interactions, and robotic platforms have been developed for high-throughput analyses to unravel the gene regulatory networks in many organisms. Use of these high-throughput techniques has led to the generation of increasingly large datasets, and several software packages have been developed to analyze such data. We previously established the currently most efficient Y1H system, meiosis-directed Y1H; however, the available software tools were not designed for processing the additional parameters suggested by meiosis-directed Y1H to avoid false positives and required programming skills for operation. RESULTS We developed a new tool named GateMultiplex with high computing performance using C++. GateMultiplex incorporated a graphical user interface (GUI), which allows the operation without any programming skills. Flexible parameter options were designed for multiple experimental purposes to enable the application of GateMultiplex even beyond Y1H platforms. We further demonstrated the data analysis from other three fields using GateMultiplex, the identification of lead compounds in preclinical cancer drug discovery, the crop line selection in precision agriculture, and the ocean pollution detection from deep-sea fishery. CONCLUSIONS The user-friendly GUI, fast C++ computing speed, flexible parameter setting, and applicability of GateMultiplex facilitate the feasibility of large-scale data analysis in life science fields.
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Estimating Local Cellular Density in Glioma Using MR Imaging Data. AJNR Am J Neuroradiol 2021; 42:102-108. [PMID: 33243897 PMCID: PMC7814791 DOI: 10.3174/ajnr.a6884] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 08/22/2020] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND PURPOSE Increased cellular density is a hallmark of gliomas, both in the bulk of the tumor and in areas of tumor infiltration into surrounding brain. Altered cellular density causes altered imaging findings, but the degree to which cellular density can be quantitatively estimated from imaging is unknown. The purpose of this study was to discover the best MR imaging and processing techniques to make quantitative and spatially specific estimates of cellular density. MATERIALS AND METHODS We collected stereotactic biopsies in a prospective imaging clinical trial targeting untreated patients with gliomas at our institution undergoing their first resection. The data included preoperative MR imaging with conventional anatomic, diffusion, perfusion, and permeability sequences and quantitative histopathology on biopsy samples. We then used multiple machine learning methodologies to estimate cellular density using local intensity information from the MR images and quantitative cellular density measurements at the biopsy coordinates as the criterion standard. RESULTS The random forest methodology estimated cellular density with R 2 = 0.59 between predicted and observed values using 4 input imaging sequences chosen from our full set of imaging data (T2, fractional anisotropy, CBF, and area under the curve from permeability imaging). Limiting input to conventional MR images (T1 pre- and postcontrast, T2, and FLAIR) yielded slightly degraded performance (R2 = 0.52). Outputs were also reported as graphic maps. CONCLUSIONS Cellular density can be estimated with moderate-to-strong correlations using MR imaging inputs. The random forest machine learning model provided the best estimates. These spatially specific estimates of cellular density will likely be useful in guiding both diagnosis and treatment.
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Imaging-Based Algorithm for the Local Grading of Glioma. AJNR Am J Neuroradiol 2020; 41:400-407. [PMID: 32029466 DOI: 10.3174/ajnr.a6405] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 12/16/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND PURPOSE Gliomas are highly heterogeneous tumors, and optimal treatment depends on identifying and locating the highest grade disease present. Imaging techniques for doing so are generally not validated against the histopathologic criterion standard. The purpose of this work was to estimate the local glioma grade using a machine learning model trained on preoperative image data and spatially specific tumor samples. The value of imaging in patients with brain tumor can be enhanced if pathologic data can be estimated from imaging input using predictive models. MATERIALS AND METHODS Patients with gliomas were enrolled in a prospective clinical imaging trial between 2013 and 2016. MR imaging was performed with anatomic, diffusion, permeability, and perfusion sequences, followed by image-guided stereotactic biopsy before resection. An imaging description was developed for each biopsy, and multiclass machine learning models were built to predict the World Health Organization grade. Models were assessed on classification accuracy, Cohen κ, precision, and recall. RESULTS Twenty-three patients (with 7/9/7 grade II/III/IV gliomas) had analyzable imaging-pathologic pairs, yielding 52 biopsy sites. The random forest method was the best algorithm tested. Tumor grade was predicted at 96% accuracy (κ = 0.93) using 4 inputs (T2, ADC, CBV, and transfer constant from dynamic contrast-enhanced imaging). By means of the conventional imaging only, the overall accuracy decreased (89% overall, κ = 0.79) and 43% of high-grade samples were misclassified as lower-grade disease. CONCLUSIONS We found that local pathologic grade can be predicted with a high accuracy using clinical imaging data. Advanced imaging data improved this accuracy, adding value to conventional imaging. Confirmatory imaging trials are justified.
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Priming of Plant Resistance to Heat Stress and Tomato Yellow Leaf Curl Thailand Virus With Plant-Derived Materials. FRONTIERS IN PLANT SCIENCE 2019; 10:906. [PMID: 31354773 PMCID: PMC6640737 DOI: 10.3389/fpls.2019.00906] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 06/26/2019] [Indexed: 05/21/2023]
Abstract
Plants are often simultaneously exposed to diverse environmental stresses, and can tune suitable responses to them through hormones. Salicylic acid (SA) and jasmonic acid (JA) signaling pathways are known to enhance resistance against heat stress and tomato yellow leaf curl Thailand virus (TYLCTHV) infection. However, there is limited information regarding alternative natural priming agents against heat stress and viruses. In this study, two plant-derived priming agents, eugenol and anise oil, were tested for their roles in conferring thermotolerance and virus resistance in tomato plants. Under heat stress, the survival rates and average fresh weight were higher in plants treated with eugenol or anise oil than in control plants. These two priming agents were further tested for antiviral activities. After TYLCTHV infection, the disease incidence and relative abundance of TYLCTHV were lower in anise oil- and eugenol-treated plants than in control plants. Further analyses revealed that a few SA, JA, and RNA silencing genes were enhanced in the former. Moreover, SA, JA, and H2O2 contents increased considerably after eugenol and anise oil treatments. Our findings imply that anise oil and eugenol initiated SA- and JA-mediated defenses to promote thermotolerance and antiviral responses of tomato plants.
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The p38-like MAP kinase modulated H 2O 2 accumulation in wounding signaling pathways of sweet potato. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 280:305-313. [PMID: 30824008 DOI: 10.1016/j.plantsci.2018.12.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 12/11/2018] [Accepted: 12/13/2018] [Indexed: 06/09/2023]
Abstract
In sweet potato (Ipomoea batatas cv Tainung 57), MAPK cascades are involved in the regulation of Ipomoelin (IPO) expression upon wounding. p38 MAPK plays an important role in plant's responses to various environmental stresses. However, the role of p38-like MAPK in wounding response is still unknown. In this study, the levels of phosphorylated-p38-like MAPK (pp38-like MAPK) in sweet potato were noticeably reduced after wounding. In addition, SB203580 (SB), a specific inhibitor blocking p38 MAPK phosphorylation, considerably decreased the accumulation of pp38-like MAPK. Expression of a wound-inducible gene IPO was elevated by SB. Moreover, it stimulated hydrogen peroxide (H2O2) production rather than cytosolic Ca2+ elevation in sweet potato leaves. However, NADPH oxidase (NOX) inhibitor diphenyleneiodonium could not inhibit IPO induction stimulated by SB. These results indicated a p38-like MAPK mechanism was involved in the regulation of IPO expression through NOX-independent H2O2 generation. In addition, the presence of the protein phosphatase inhibitor okadaic acid or the MEK1/ERK inhibitor PD98059 repressed the H2O2- or SB-induced IPO expression, demonstrating phosphatase(s) and MEK1/ERK functioning in the downstream of H2O2 and pp38-like MAPK in the signal transduction pathway stimulating IPO. Conclusively, wounding decreased the amount of pp38-like MAPK, stimulated H2O2 production, and then induced IPO expression.
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MicroR408 regulates defense response upon wounding in sweet potato. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:469-483. [PMID: 30403812 PMCID: PMC6322576 DOI: 10.1093/jxb/ery381] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 11/02/2018] [Indexed: 05/08/2023]
Abstract
MiRNAs play diverse roles in plant development and defense responses by binding to their mRNA targets based on sequence complementarity. Here, we investigated a wound-related miR408 and its target genes in sweet potato (Ipomoea batatas) by small RNA deep sequencing and transcriptome analysis. The expression patterns of miR408 and the miR408 precursor were significantly repressed by wounding and jasmonate (JA). In contrast, expression of the putative target genes IbKCS (3-ketoacyl-CoA synthase 4), IbPCL (plantacyanin), and IbGAUT (galacturonosyltransferase 7-like) of miR408 was increased following wounding, whereas only IbKCS was increased after JA treatment. Target cleavage site mapping and Agrobacterium-mediated transient assay demonstrated that IbKCS, IbPCL, and IbGAUT were the targets of miR408. The expression of miR408 target genes was repressed in transgenic sweet potatoes overexpressing miR408. These data indicated a relationship between miR408 and its target genes. Notably, miR408-overexpressing plants showed a semi-dwarf phenotype and attenuated resistance to insect feeding, while transgenic plants overexpressing IbKCS exhibited more insect resistance than plants overexpressing only the empty vector. Collectively, sweet potato reduces the abundance of miR408 upon wounding to elevate the expression of IbKCS, IbPCL, and IbGAUT. The expression of IbKCS enhances the defense system against herbivore wounding.
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MicroRNA160 Modulates Plant Development and Heat Shock Protein Gene Expression to Mediate Heat Tolerance in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2018; 9:68. [PMID: 29449855 PMCID: PMC5799662 DOI: 10.3389/fpls.2018.00068] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 01/12/2018] [Indexed: 05/21/2023]
Abstract
Global warming is causing a negative impact on plant growth and adversely impacts on crop yield. MicroRNAs (miRNAs) are critical in regulating the expression of genes involved in plant development as well as defense responses. The effects of miRNAs on heat-stressed Arabidopsis warrants further investigation. Heat stress increased the expression of miR160 and its precursors but considerably reduced that of its targets, ARF10, ARF16, and ARF17. To study the roles of miR160 during heat stress, transgenic Arabidopsis plants overexpressing miR160 precursor a (160OE) and artificial miR160 (MIM160), which mimics an inhibitor of miR160, were created. T-DNA insertion mutants of miR160 targets were also used to examine their tolerances to heat stress. Results presented that overexpressing miR160 improved seed germination and seedling survival under heat stress. The lengths of hypocotyl elongation and rachis were also longer in 160OE than the wild-type (WT) plants under heat stress. Interestingly, MIM160 plants showed worse adaption to heat. In addition, arf10, arf16, and arf17 mutants presented similar phenotypes to 160OE under heat stress to advance abilities of thermotolerance. Moreover, transcriptome and qRT-PCR analyses revealed that HSP17.6A, HSP17.6II, HSP21, and HSP70B expression levels were regulated by heat in 160OE, MIM160, arf10, arf16, and arf17 plants. Hence, miR160 altered the expression of the heat shock proteins and plant development to allow plants to survive heat stress.
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[Enhancing Soft-tissue Reattachment with Artificial Mesh in Joint Endoprosthetic Reconstruction for Bone Tumors]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 2017; 39:540-544. [PMID: 28728303 DOI: 10.3760/cma.j.issn.0253-3766.2017.07.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the operative method and clinical application of the BARD(®) Mesh in enhancing joint stability and function of endoprosthetic reconstruction for bone tumors. Methods: From Jan 2013 to Jun 2015, the clinical data of 51 patients aged (44.75±23.18) years underwent wide resection of tumor and endoprosthetic reconstruction using the BARD(®) Mesh were collected. Among them, 27 were male and 24 were female. The surgical treatments received by these patients included 5 shoulder arthroplasties, 12 elbow replacements, 12 hip replacements and 32 knee replacements (including 24 femoral tumors and 8 tibial tumors). According to the pathologic type, there were 12 metastatic tumors, 20 osteosarcomas, 7 chondrosarcomas, 5 malignant fibrous histiocytomas, 4 giant cell tumors of bone, 1 Ewing sarcoma, 1 leiomyosarcoma and 1 pigmented villonodular synovitis (pvns). These patients received extensive tumor resection, tumorous prosthesis replacement, preserved articular capsule and muscles repair with artificial mesh and endoprosthesis wrapping. The curative effect including joints range of motion and Musculoskeletal Tumour Society Scores (MSTS) were evaluated. Results: The median follow-up time was (19.75±8.17) months. The drainages were removed out on an average of 4 days after operation. The postoperative complications included 2 superficial incision infection, 1 deep incision infection and 1 osteofascial compartment syndrome, infection or dislocation of prosthesis wasn't observed. The mean active flexion of shoulder joint after replacement was (34.00±10.84)°, mean active abduction was (20.00±9.35)° and the mean MSTS was 19.80±9.54. The superior rate of shoulder flexion function was 0. The mean active flexion of elbow joint after replacement was (75.00±7.07)°, mean active abduction was (-5.00±7.07)° and the mean MSTS was 25.00±2.83. The superior rate of elbow flexion function was 50.0% (1/2). The mean active flexion of hip joint after replacement was (86.67±20.60)°, mean active abduction was (2.08±4.98)° and the mean MSTS was 25.42±1.78. The superior rate of hip flexion function was 83.3% (10/12). The mean active flexion of knee joint after replacement was (89.69±22.39)°, mean active abduction was (-0.63±1.68)° and the mean MSTS was 23.31±2.09. The superior rate of knee flexion function was 50.0%(16/32). Among them, the superior rate of femoral flexion function was 66.7% (16/24), the superior rate of tibial flexion function was 0. All of patients were satisfied with the curative effect of operation at the end of follow-up time. Conclusions: The BARD(®) Mesh may enhance the attachment of soft-tissue to endoprosthesis, improve the joint stability, decrease the endoprosthetic infection and dislocation, facilitate the attachment of tendon to endoprosthesis and recover the muscular motivation after endoprosthetic reconstruction. This plays an important role in joint stability and motivation reconstruction of soft-tissue impairment, effectively prevents surgical complications.
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Performance Assessment for Brain MR Imaging Registration Methods. AJNR Am J Neuroradiol 2017; 38:973-980. [PMID: 28279984 DOI: 10.3174/ajnr.a5122] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 12/12/2016] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Clinical brain MR imaging registration algorithms are often made available by commercial vendors without figures of merit. The purpose of this study was to suggest a rational performance comparison methodology for these products. MATERIALS AND METHODS Twenty patients were imaged on clinical 3T scanners by using 4 sequences: T2-weighted, FLAIR, susceptibility-weighted angiography, and T1 postcontrast. Fiducial landmark sites (n = 1175) were specified throughout these image volumes to define identical anatomic locations across sequences. Multiple registration algorithms were applied by using the T2 sequence as a fixed reference. Euclidean error was calculated before and after each registration and compared with a criterion standard landmark registration. The Euclidean effectiveness ratio is the fraction of Euclidean error remaining after registration, and the statistical effectiveness ratio is similar, but accounts for dispersion and noise. RESULTS Before registration, error values for FLAIR, susceptibility-weighted angiography, and T1 postcontrast were 2.07 ± 0.55 mm, 2.63 ± 0.62 mm, and 3.65 ± 2.00 mm, respectively. Postregistration, the best error values for FLAIR, susceptibility-weighted angiography, and T1 postcontrast were 1.55 ± 0.46 mm, 1.34 ± 0.23 mm, and 1.06 ± 0.16 mm, with Euclidean effectiveness ratio values of 0.493, 0.181, and 0.096 and statistical effectiveness ratio values of 0.573, 0.352, and 0.929 for rigid mutual information, affine mutual information, and a commercial GE registration, respectively. CONCLUSIONS We demonstrate a method for comparing the performance of registration algorithms and suggest the Euclidean error, Euclidean effectiveness ratio, and statistical effectiveness ratio as performance metrics for clinical registration algorithms. These figures of merit allow registration algorithms to be rationally compared.
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Signal transduction and regulation of IbpreproHypSys in sweet potato. PLANT, CELL & ENVIRONMENT 2016; 39:1576-87. [PMID: 26924170 DOI: 10.1111/pce.12729] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 02/04/2016] [Accepted: 02/09/2016] [Indexed: 05/28/2023]
Abstract
Hydroxyproline-rich glycopeptides (HypSys) are small signalling peptides containing 18-20 amino acids. The expression of IbpreproHypSys, encoding the precursor of IbHypSys, was induced in sweet potato (Ipomoea batatas cv. Tainung 57) through wounding and IbHypSys treatments by using jasmonate and H2 O2 . Transgenic sweet potatoes overexpressing (OE) and silencing [RNA interference (RNAi)] IbpreproHypSys were created. The expression of the wound-inducible gene for ipomoelin (IPO) in the local and systemic leaves of OE plants was stronger than the expression in wild-type (WT) and RNAi plants after wounding. Furthermore, grafting experiments indicated that IPO expression was considerably higher in WT stocks receiving wounding signals from OE than from RNAi scions. However, wounding WT scions highly induced IPO expression in OE stocks. These results indicated that IbpreproHypSys expression contributed towards sending and receiving the systemic signals that induced IPO expression. Analysing the genes involved in the phenylpropanoid pathway demonstrated that lignin biosynthesis was activated after synthetic IbHypSys treatment. IbpreproHypSys expression in sweet potato suppressed Spodoptera litura growth. In conclusion, wounding induced the expression of IbpreproHypSys, whose protein product was processed into IbHypSys. IbHypSys stimulated IbpreproHypSys and IPO expression and enhanced lignin biosynthesis, thus protecting plants from insects.
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Temperature-Dependent Development and Reproductive Traits of Tyrophagus putrescentiae (Sarcoptiformes: Acaridae) Reared on Different Edible Mushrooms. ENVIRONMENTAL ENTOMOLOGY 2015; 44:392-399. [PMID: 26313193 DOI: 10.1093/ee/nvu064] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/05/2014] [Indexed: 06/04/2023]
Abstract
China is the largest producer, consumer, and exporter of mushrooms in the world. The storage mite, Tyrophagus putrescentiae Schrank, is one of the most important arthropod pests in mushroom cultivation. This study investigated the development and reproductive traits of this mite reared on four mushroom species: Agaricus bisporus Lange, Pleurotus ostreatus Kumm, Auricularia polytricha (Mont.) Sacc., and Flammulina velutipes (Fr.) Sing., at seven constant temperatures ranging from 16 to 34 °C at 80% relative humidity. Development time for the immature stages decreased with increasing temperature, and was also significantly affected by mushroom species. The shortest immature developmental period (7.0 ± 0.2 d) was observed at 31 °C when reared on F. velutipes, while the longest development was at 16 °C (36.0 ± 0.3 d) reared on P. ostreatus. The effects of temperature and mushroom hosts on the development, female longevity, and reproduction were also significant. The lower threshold temperatures from egg-to-adult for the four mushroom species were 11.97, 12.02, 10.80, and 11.57 °C, for A. bisporus, P. ostreatus, Au. polytricha, and F. velutipes, and the thermal constants were 133.3, 136.8, 165.2, and 135.9 degree days (°C d), for the same mushroom species, respectively. Life table parameters at 25 °C were estimated as follows: net reproductive rates (R0), 59.16, 28.94, 42.62, and 62.93, and intrinsic rate of natural increase (rm), 0.24, 0.13, 0.17, and 0.24, respectively. These results suggest that these mushrooms are suitable hosts for T. putrescentiae, and the storage mite may be able to adapt to higher temperatures.
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Recombinant human kallistatin inhibits angiogenesis by blocking VEGF signaling pathway. J Cell Biochem 2014; 115:575-84. [PMID: 24129914 DOI: 10.1002/jcb.24693] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 10/10/2013] [Indexed: 12/24/2022]
Abstract
Kallistatin has been recognized as an endogenous angiogenic inhibitor. However, the underlying molecular mechanism remains poorly understood. Taking it into account that vascular endothelial growth factor (VEGF) has been implicated in all aspects of normal and pathological vasculogenesis and angiogenesis. In this study, we investigated whether VEGF signaling pathway was impacted by the anti-angiogenic effect of recombinant human kallistatin (rhKal). We found that the rhKal inhibited proliferation as well as induced apoptosis of cultured human umbilical vein endothelial cells (HUVECs) in both concentration- and time-dependent manners. The rhKal also suppressed the VEGF-induced migration and tube formation of HUVECs. Furthermore, our data revealed that the rhKal suppressed the VEGF165-stimulated tyrosine phosphorylation of VEGFR-2 as well as its downstream signal molecular activation. The inhibition of receptor phosphorylation was correlated with a decrease in VEGF-triggered phosphorylation of angiogenesis signal molecules AKT and ERK, but not stress-related JNK. Taken together, these findings added the knowledge for us to understand the anti-angiogenic mechanism of kallistatin, which suggested that the rhKal could be worth as a candidate compound for further development for the purpose of anti-angiogenic therapies.
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Carbon monoxide regulates the expression of the wound-inducible gene ipomoelin through antioxidation and MAPK phosphorylation in sweet potato. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:5279-90. [PMID: 25063862 PMCID: PMC4157712 DOI: 10.1093/jxb/eru291] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/04/2014] [Accepted: 06/06/2014] [Indexed: 05/24/2023]
Abstract
Carbon monoxide (CO), one of the haem oxygenase (HO) products, plays important roles in plant development and stress adaptation. However, the function of CO involved in wounding responses is seldom studied. A wound-inducible gene, ipomoelin (IPO), of sweet potato (Ipomoea batatas cv. Tainung 57) was used as a target to study the regulation of CO in wounding responses. After wounding for 1h, the endogenous CO content and IbHO expression level were significantly reduced in leaves. IPO expression upon wounding was prohibited by the HO activator hemin, whereas the HO inhibitor zinc protoporphyrin IX elevated IPO expression. The IPO expression induced by wounding, H2O2, or methyl jasmonate was inhibited by CO. CO also affected the activities of ascorbate peroxidase, catalase, and peroxidase, and largely decreased H2O2 content in leaves. CO inhibited the extracellular signal-regulated kinase (ERK) phosphorylation induced by wounding. IbMAPK, the ERK of sweet potato, was identified by immunoblotting, and the interaction with its upstream activator, IbMEK1, was further confirmed by bimolecular fluorescence complementation and co-immunoprecipitation. Conclusively, wounding in leaves repressed IbHO expression and CO production, induced H2O2 generation and ERK phosphorylation, and then stimulated IPO expression.
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Expression of a gene encoding β-ureidopropionase is critical for pollen germination in tomatoes. PHYSIOLOGIA PLANTARUM 2014; 150:425-435. [PMID: 24033314 DOI: 10.1111/ppl.12085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Accepted: 06/13/2013] [Indexed: 05/28/2023]
Abstract
Global warming has seriously decreased world crop yield. High temperatures affect development, growth and, particularly, reproductive tissues in plants. A gene encoding β-ureidopropionase (SlUPB1, EC 3.5.1.6) was isolated from the stamens of a heat-tolerant tomato (CL5915) using suppression subtractive hybridization. SlUPB1 catalyzes the production of β-alanine, the only β-form amino acid in nature. In the anthesis stage, SlUPB1 expression in CL5915 stamens, growing at 35/30°C (day/night), was 2.16 and 2.93 times greater than that in a heat-sensitive tomato (L4783) cultivated at 30/25°C or 25/20°C, respectively. Transgenic tomatoes, upregulating SlUPB1 in L4783 and downregulating SlUPB1 in CL5915, were constructed, and the amount of β-alanine measured by liquid chromatography-electrospray ionization-mass spectrometry in the transgenic overexpression of SlUPB1 was higher than that of L4783. However, the β-alanine in the transgenics downregulating SlUPB1 was significantly lower than the β-alanine of CL5915. Pollen germination rates of these transgenics were analyzed under different developmental and germinating temperatures. The results indicated that germination rates of transgenics overexpressing SlUPB1 were higher than germination rates of the background tomato L4783. Germination rates of transgenics downregulating SlUPB1 were significantly lower than germination rates of background tomato CL5915, indicating the necessity of functional SlUPB1 for pollen germination. Pollen germinating in the buffer with the addition of β-alanine further indicated that β-alanine effectively enhanced pollen germination in tomatoes with low SlUPB1 expression. Together, these results showed that the expression of SlUPB1 is important for pollen germination, and β-alanine may play a role in pollen germination under both optimal and high temperatures.
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Interaction of small RNA-8105 and the intron of IbMYB1 RNA regulates IbMYB1 family genes through secondary siRNAs and DNA methylation after wounding. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 75:781-794. [PMID: 23663233 DOI: 10.1111/tpj.12238] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 05/06/2013] [Accepted: 05/08/2013] [Indexed: 06/02/2023]
Abstract
Small RNAs (sRNAs) play important roles in plants under stress conditions. However, limited research has been performed on the sRNAs involved in plant wound responses. In the present study, a novel wounding-induced sRNA, sRNA8105, was identified in sweet potato (Ipomoea batatas cv. Tainung 57) using microarray analysis. It was found that expression of sRNA8105 increased after mechanical wounding. Furthermore, Dicer-like 1 (DCL1) is required for the sRNA8105 precursor (pre-sRNA8105) to generate 22 and 24 nt mature sRNA8105. sRNA8105 targeted the first intron of IbMYB1 (MYB domain protein 1) before RNA splicing, and mediated RNA cleavage and DNA methylation of IbMYB1. The interaction between sRNA8105 and IbMYB1 was confirmed by cleavage site mapping, agro-infiltration analyses, and use of a transgenic sweet potato over-expressing pre-sRNA8105 gene. Induction of IbMYB1-siRNA was observed in the wild-type upon wounding and in transgenic sweet potato over-expressing pre-sRNA8105 gene without wounding, resulting in decreased expression of the whole IbMYB1 gene family, i.e. IbMYB1 and the IbMYB2 genes, and thus directing metabolic flux toward biosynthesis of lignin in the phenylpropanoid pathway. In conclusion, sRNA8105 induced by wounding binds to the first intron of IbMYB1 RNA to methylate IbMYB1, cleave IbMYB1 RNA, and trigger production of secondary siRNAs, further repressing the expression of the IbMYB1 family genes and regulating the phenylpropanoid pathway.
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MicroR828 regulates lignin and H2O2 accumulation in sweet potato on wounding. THE NEW PHYTOLOGIST 2012; 196:427-440. [PMID: 22931461 DOI: 10.1111/j.1469-8137.2012.04277.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 07/12/2012] [Indexed: 05/04/2023]
Abstract
MicroRNAs (miRNAs) are small noncoding RNAs which post-transcriptionally regulate gene expression by directing mRNA cleavage or translational inhibition. miRNAs play multiple roles in the growth, development and stress responses in plants. However, little is known of the wounding-responsive miRNAs and their regulation. Here, we investigated the expression patterns of microR828 (miR828) on wounding in sweet potato (Ipomoea batatas cv Tainung 57). The expression of miR828 was only detected in leaves, and was induced by wounding rather than by ethylene, hydrogen peroxide (H2O2), methyl jasmonate or nitric oxide (NO). Moreover, cyclic guanosine monophosphate (cGMP) was necessary for miR828 accumulation in leaves on wounding. Two miR828 target candidates, named IbMYB and IbTLD, were obtained by cDNA cloning, and their mRNA cleavage caused by miR828 was confirmed by cleavage site mapping, agro-infiltration and transgenics studies. The reduction in IbMYB and IbTLD expression coincided with the induction of miR828, demonstrating that IbMYB and IbTLD might be miR828 targets. Furthermore, transgenic sweet potato overexpressing miR828 precursor affected lignin and H2O2 contents. These results showed that cGMP could regulate wounding-responsive miR828, which repressed the expression of IbMYB and IbTLD. Subsequently, lignin and H2O2 were accumulated to participate in defense mechanisms.
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The bile steroid chenodeoxycholate is a potent antagonist at NMDA and GABA(A) receptors. Neurosci Lett 2011; 506:322-6. [PMID: 22155097 DOI: 10.1016/j.neulet.2011.11.036] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Revised: 11/19/2011] [Accepted: 11/21/2011] [Indexed: 01/02/2023]
Abstract
The bile steroids (BS) cholic acid and chenodeoxycholic acid are produced in hepatocytes and in the brain. Nothing is known about neuronal actions of BS. Deficiency in a 27-hydroxylase enzyme coincides with reduced production of chenodeoxycholic acid (CDCA) and a relative increase in cholic acid in an inherited lipid storage disease, cerebrotendinous xanthomatosis, characterized by neurological dysfunctions, which can be treated by dietary CDCA. We have examined the modulation of hypothalamic network activity by nine common BS. Cholate and CDCA significantly reduced the firing of hypothalamic neurons and synchronized network activity with CDCA being nearly 10 times more potent. The synthetic BS dehydrocholate synchronized the activity without affecting the firing rate. Gabazine, a GABA(A) receptor antagonist, occluded synchronization by BS. Whole-cell patch clamp recordings revealed a block of NMDA- and GABA(A)-receptors by BS. Potencies of nine common BS differed between NMDA and GABA(A) receptors, however in both cases they correlated with BS affinities for albumin but not with their lipophilicity, supporting a direct action at ligand gated ion channels. GABAergic synaptic currents displayed a faster decay under BS. Our data provide new insight into extrahepatic functions of BS revealing their neuroactive potential.
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Nitric oxide activates superoxide dismutase and ascorbate peroxidase to repress the cell death induced by wounding. PLANT MOLECULAR BIOLOGY 2011; 77:235-49. [PMID: 21833542 DOI: 10.1007/s11103-011-9805-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2011] [Accepted: 06/29/2011] [Indexed: 05/03/2023]
Abstract
Wounding caused by rain, wind, and pathogen may lead plants to onset defense response. Previous studies indicated that mechanical wounding stimulates plants to generate nitric oxide (NO) and hydrogen peroxide (H(2)O(2)). In this study, the functions of NO and H(2)O(2) after wounding in sweet potato (Ipomoea batatas cv. Tainung 57) was further analyzed. Mechanical wounding damaged cells and resulted in necrosis, but the presence of NO donors or NO scavenger might reduce or enhance the cell death caused by wounding, respectively. The amount of H(2)O(2) induced by wounding was also decreased or increased when plants were incubated with NO donors or NO scavenger, individually. These results indicate that NO may regulate H(2)O(2) generation to affect cell death. NO-induced proteins isolated from two-dimensional electrophoresis were identified to be Copper/Zinc superoxide dismutases (CuZnSODs). The activities of CuZnSODs and ascorbate peroxidase (APX) could be enhanced by NO. In addition, the expression of CuZnSOD and APX was induced by wounding via NO, and their expression was further stimulated by NO through the generation of cGMP. The influx of calcium ions and the activity of NADPH oxidase were also involved in the NO signal transduction pathway inducing APX expression. Collectively, the generation of H(2)O(2) in wounded plants might trigger cell death. Meanwhile, the production of NO induced by wounding stimulated signal transducers including cGMP, calcium ions, and H(2)O(2) to activate CuZnSOD and APX, which further decreased H(2)O(2) level and reduced the cell death caused by wounding.
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Abstract
Sensory neurons transduce various stimuli including temperature, pain, and touch from the periphery to the central nervous system. Sensory neuron development is governed by a combination of extracellular cues and specific gene expression. We demonstrated that the transcription factor Sox11 was highly expressed in the developing sensory neurons. To test the function of Sox11, we used a knockin mouse model where the entire coding region of Sox11 was replaced by a LacZ reporter. The ablation of Sox11 caused severe reduction in sensory neuron survival in the trigeminal and dorsal root ganglia, although it did not affect migration of neural crest cells or acquisition of major sensory neuron subtypes. We further demonstrated that ablating Sox11 caused an arrest of axonal outgrowth in vivo and in vitro. This defect could not be fully rescued by blocking cell death. Our data suggest that Sox11 is a key regulator of sensory neuron development.
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Expression of an Oncidium Gene Encoding a Patatin-Like Protein Delays Flowering in Arabidopsis by Reducing Gibberellin Synthesis. ACTA ACUST UNITED AC 2011; 52:421-35. [DOI: 10.1093/pcp/pcq206] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Differential effects of acute and repeat dosing with the H3 antagonist GSK189254 on the sleep-wake cycle and narcoleptic episodes in Ox-/- mice. Br J Pharmacol 2009; 157:104-17. [PMID: 19413575 DOI: 10.1111/j.1476-5381.2009.00205.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Histamine H3 receptor antagonists are currently being evaluated in clinical trials for a number of central nervous system disorders including narcolepsy. These agents can increase wakefulness (W) in cats and rodents following acute administration, but their effects after repeat dosing have not been reported previously. EXPERIMENTAL APPROACH EEG and EMG recordings were used to investigate the effects of acute and repeat administration of the novel H3 antagonist GSK189254 on the sleep-wake cycle in wild-type (Ox+/+) and orexin knockout (Ox-/-) mice, the latter being genetically susceptible to narcoleptic episodes. In addition, we investigated H3 and H1 receptor expression in this model using radioligand binding and autoradiography. KEY RESULTS In Ox+/+ and Ox-/- mice, acute administration of GSK189254 (3 and 10 mg x kg(-1) p.o.) increased W and decreased slow wave and paradoxical sleep to a similar degree to modafinil (64 mg x kg(-1)), while it reduced narcoleptic episodes in Ox-/- mice. After twice daily dosing for 8 days, the effect of GSK189254 (10 mg x kg(-1)) on W in both Ox+/+ and Ox-/- mice was significantly reduced, while the effect on narcoleptic episodes in Ox-/- mice was significantly increased. Binding studies revealed no significant differences in H3 or H1 receptor expression between Ox+/+ and Ox-/- mice. CONCLUSIONS AND IMPLICATIONS These studies provide further evidence to support the potential use of H3 antagonists in the treatment of narcolepsy and excessive daytime sleepiness. Moreover, the differential effects observed on W and narcoleptic episodes following repeat dosing could have important implications in clinical studies.
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A CMOS neuroelectronic interface based on two-dimensional transistor arrays with monolithically-integrated circuitry. Biosens Bioelectron 2009; 24:1757-64. [PMID: 18951013 DOI: 10.1016/j.bios.2008.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Revised: 09/03/2008] [Accepted: 09/04/2008] [Indexed: 11/17/2022]
Abstract
The ability to monitor and to elicit neural activity with a high spatiotemporal resolution has grown essential for studying the functionality of neuronal networks. Although a variety of microelectrode arrays (MEAs) has been proposed, very few MEAs are integrated with signal-processing circuitry. As a result, the maximum number of electrodes is limited by routing complexity, and the signal-to-noise ratio is degraded by parasitics and noise interference. This paper presents a single-chip neuroelectronic interface integrating oxide-semiconductor field-effect transistors (OSFETs) with signal-processing circuitry. After the chip was fabricated with the standard complementary-metal-oxide-semiconductor (CMOS) process, polygates of specific transistors were etched at die-level to form OSFETs, while metal layers were retained to connect the OSFETs into two-dimensional arrays. The complete removal of polygates was confirmed by high-resolution image scanners, and the reliability of OSFETs was examined by measuring their electrical characteristics. Through a gate oxide of only 7nm thick, each OSFET can record and stimulate neural activity extracellularly by capacitive coupling. The capability of the full chip in neural recording and stimulation was further experimented using the well-characterised escape circuit of the crayfish. Experimental results indicate that the OSFET-based neuroelectronic interface can be used to study neuronal networks as faithfully as conventional electrophysiological tools. Moreover, the proposed simple, die-level fabrication process of the OSFETs underpins the development of various field-effect biosensors on a large scale with on-chip circuitry.
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CMOS-micromachined, two-dimenisional transistor arrays for neural recording and stimulation. ACTA ACUST UNITED AC 2007; 2007:2365-8. [PMID: 18002468 DOI: 10.1109/iembs.2007.4352802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In-plane microelectrode arrays have proven to be useful tools for studying the connectivities and the functions of neural tissues. However, seldom microelectrode arrays are monolithically-integrated with signal-processing circuits, without which the maximum number of electrodes is limited by the compromise with routing complexity and interferences. This paper proposes a CMOS-compatible, two-dimensional array of oxide-semiconductor field-effect transistors(OSFETs), capable of both recording and stimulating neuronal activities. The fabrication of the OSFETs not only requires simply die-level, post-CMOS micromachining process, but also retains metal layers for monolithic integration with signal-processing circuits. A CMOS microsystem containing the OSFET arrays and gain-programmable recording circuits has been fabricated and tested. The preliminary testing results are presented and discussed.
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Hair follicle: a reliable source of recipient origin after allogeneic hematopoietic stem cell transplantation. Bone Marrow Transplant 2007; 40:871-4. [PMID: 17704789 DOI: 10.1038/sj.bmt.1705823] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Blood, buccal swab and hair follicles are among the most commonly used sources for forensic science, parentage testing and personal identification. A total of 29 patients who have had a sustained engraftment from 15 months to 21.5 years after allogeneic hematopoietic stem cell transplantation (HSCT) without rejection, relapse or chronic GVHD involving oral mucosa were enrolled for a chimerism study. PCR-amplified short tandem repeat analyses were conducted per patient every 3 months for at least three consecutive times. The results for blood were all donor type except one who had a mixed chimerism, 14.5 years after receiving a transplant for lymphoma. As for buccal swab, mixed chimerism ranging from 10 to 96% donor origin was noted for 28 recipients except the one who had mixed chimerism of blood and retained total recipient type. In contrast, hair follicles were 100% recipient type for the entire group. It is concluded that the hair follicle is devoid of adult stem cell plasticity and may serve as a reliable source of recipient's origin when pre-transplant DNA fingerprinting or reference DNA is not available for people who have successfully received allogeneic HSCT while in need of a personal identification.
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Brain structures and mechanisms involved in the control of cortical activation and wakefulness, with emphasis on the posterior hypothalamus and histaminergic neurons. Sleep Med Rev 2007; 4:471-503. [PMID: 17210278 DOI: 10.1053/smrv.2000.0116] [Citation(s) in RCA: 200] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Wakefulness is a functional brain state that allows the performance of several "high brain functions", such as diverse behavioural, cognitive and emotional activities. Present knowledge at the whole animal or cellular level suggests that the maintenance of the cerebral cortex in this highly complex state necessitates the convergent and divergent activity of an ascending network within a large reticular zone, extending from the medulla to the forebrain and involving four major subcortical structures (the thalamus, basal forebrain, posterior hypothalamus and brainstem monoaminergic nuclei), their integral interconnections and several neurotransmitters, such as glutamate, acetylcholine, histamine and noradrenaline. In this mini-review, the importance of the thalamus, basal forebrain and brainstem monoaminergic neurons in wake control is briefly summarized, before turning our attention to the posterior hypothalamus and histaminergic neurons, which have been far less studied. Classical and recent experimental data are summarized, supporting the hypothesis that (1) the posterior hypothalamus constitutes one of the brain ascending activating systems and plays an important role in waking; (2) this function is mediated, in part, by histaminergic neurons, which constitute one of the excitatory sources for cortical activation during waking; (3) the mechanisms of histaminergic arousal involve both the ascending and descending projections of histaminergic neurons and their interactions with diverse neuronal populations, such as neurons in the pre-optic area and cholinergic neurons; and (4) other widespread-projecting neurons in the posterior hypothalamus also contribute to the tonic cortical activation during wakefulness and/or paradoxical sleep.
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The brain H3-receptor as a novel therapeutic target for vigilance and sleep–wake disorders. Biochem Pharmacol 2007; 73:1157-71. [PMID: 17288995 DOI: 10.1016/j.bcp.2007.01.002] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Revised: 11/28/2006] [Accepted: 01/03/2007] [Indexed: 11/26/2022]
Abstract
Brain histaminergic neurons play a prominent role in arousal and maintenance of wakefulness (W). H(3)-receptors control the activity of histaminergic neurons through presynaptic autoinhibition. The role of H(3)-receptor antagonists/inverse agonists (H(3)R-antagonists) in the potential therapy of vigilance deficiency and sleep-wake disorders were studied by assessing their effects on the mouse cortical EEG and sleep-wake cycle in comparison to modafinil and classical psychostimulants. The H(3)R-antagonists, thioperamide and ciproxifan increased W and cortical EEG fast rhythms and, like modafinil, but unlike amphetamine and caffeine, their waking effects were not accompanied by sleep rebound. Conversely, imetit (H(3)R-agonist) enhanced slow wave sleep and dose-dependently attenuated ciproxifan-induced W, indicating that the effects of both ligands involve H(3)-receptor mechanisms. Additional studies using knockout (KO) mice confirmed the essential role of H(3)-receptors and histamine-mediated transmission in the wake properties of H(3)R-antagonists. Thus ciproxifan produced no increase in W in either histidine-decarboxylase (HDC, histamine-synthesizing enzyme) or H(1)- or H(3)-receptor KO-mice whereas its waking effects persisted in H(2)-receptor KO-mice. These data validate the hypothesis that H(3)R-antagonists, through disinhibition of H(3)-autoreceptors, enhancing synaptic histamine that in turn activates postsynaptic H(1)-receptors promoting W. Interestingly amphetamine and modafinil, despite their potent arousal effects, appear unlikely to depend on histaminergic mechanism as their effects still occurred in HDC KO-mice. The present study thus distinguishes two classes of wake-improving agents: the first acting through non-histaminergic mechanisms and the second acting via histamine and supports brain H(3)-receptors as potentially novel therapeutic targets for vigilance and sleep-wake disorders.
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Modafinil inhibits rat midbrain dopaminergic neurons through D2-like receptors. Neuropharmacology 2006; 52:626-33. [PMID: 17070873 DOI: 10.1016/j.neuropharm.2006.09.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Revised: 08/22/2006] [Accepted: 09/13/2006] [Indexed: 01/18/2023]
Abstract
Modafinil is a well-tolerated medication for excessive sleepiness, attention-deficit disorder, cocaine dependence and as an adjunct to antidepressants with low propensity for abuse. We investigated the modafinil action on identified dopaminergic and GABAergic neurons in the ventral tegmental area (VTA) and substantia nigra (SN) of rat brain slices. Modafinil (20 microM) inhibited the firing of dopaminergic, but not GABAergic neurons. This inhibition was maintained in the presence of tetrodotoxin and was accompanied by hyperpolarization. Sulpiride (10 microM), a D2-receptor antagonist, but not prazosine (20 microM, an alpha1-adrenoreceptor blocker) abolished the modafinil action. Inhibition of dopamine reuptake with a low dose of nomifensine (1 microM) reduced the firing of DA neurons in a sulpiride-dependent manner and blunted the effect of modafinil. On acutely isolated neurons, modafinil evoked D2-receptor-mediated outward currents in tyrosine-hydroxylase positive cells, identified by single-cell RT-PCR, which reversed polarity near the K(+) equilibrium potential and were unchanged in the presence of nomifensine. Thus modafinil directly inhibits DA neurons through D2 receptors.
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Novel polymorphisms in exons 6 and 7 of A/B alleles detected by polymerase chain reaction-single strand conformation polymorphism. Vox Sang 2006; 90:119-27. [PMID: 16430670 DOI: 10.1111/j.1423-0410.2005.00729.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND OBJECTIVES The ABO blood group system is the most important blood group system in transfusion medicine. In addition to the major A, B and O alleles, many rare alleles have been defined. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and analysis by PCR sequence specific primers (SSP) are commonly conducted for genotyping but have the limitation of being unable to detect unknown substitution(s) in amplified DNA fragments, whereas PCR-single strand conformation polymorphism (SSCP) can be used for both. MATERIALS AND METHODS Three-hundred unrelated blood donors of the AB phenotype were enrolled. Four pairs of primers were designed to constitute two sets of multiplex PCRs: this amplifies four fragments spanning the entire exon 6 and its immediate flanking regions, nucleotides 432-1065, as well as the 3' untranslated region of exon 7 of the ABO gene. The SSCP electrophoresis was carried out on a 12.5% polyacrylamide gel in a GenePhor electrophoresis unit. For those with unexpected banding patterns, SSCP analyses were performed in duplicate and samples were cloned and sequenced for exons 6 and 7. RESULTS Seven samples were noted to have six variant alleles, of which five have not been previously reported in the literature. Of these five novel variants, four were derived from the B allele, while the other derived from the A allele. CONCLUSIONS By using PCR-SSCP, five novel A/B alleles were found.
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A two-state model for the multilamellar structure of a DNA/cationic lipid complex in the bulk. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:9432-9436. [PMID: 15491171 DOI: 10.1021/la0488856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Polyanionic DNA can bind electrostatically with cationic lipids to form a complex used for gene delivery and nanostructure construction. Here, we reveal two multilamellar phases, L(I) and L(II), characterized by distinct states of lipid packing and DNA conformation in a DNA/cationic lipid complex in the bulk state. The L(II) phase, formed when the lipids are in excess of DNA in terms of overall ionic charge, is composed of B-DNA confined between the bilayers with the lipid tails aligning normal to the lamellar interface. When DNA becomes in excess of the lipids, the L(I) phase in which the DNA is bound with the tilted lipid chains adopting the A conformation is favored because this configuration offers more economical electrostatic binding between these two components.
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Changes in motoric, exploratory and emotional behaviours and neuronal acetylcholine content and 5-HT turnover in histidine decarboxylase-KO mice. Eur J Neurosci 2004; 20:1051-8. [PMID: 15305873 DOI: 10.1111/j.1460-9568.2004.03546.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Histamine has been implicated, inter alia, in mechanisms underlying arousal, exploratory behaviour and emotionality. Here, we investigated behavioural and neurochemical parameters related to these concepts, including open-field activity, rotarod performance and anxiety, as well as brain acetylcholine and 5-HT concentrations of mice deficient for the histidine decarboxylase (HDC) gene. These mice are unable to synthesize histamine from its precursor histidine. The HDC-knockout mice showed reduced exploratory activity in an open-field, but normal habituation to a novel environment. They behaved more anxious than the controls, as assessed by the height-fear task and the graded anxiety test, a modified elevated plus-maze. Furthermore, motor coordination on the rotarod was superior to controls. Biochemical assessments revealed that the HDC-knockout mice had higher acetylcholine concentrations and a significantly higher 5-HT turnover in the frontal cortex, but reduced acetylcholine levels in the neostriatum. These results are suggestive of important interactions between neuronal histamine and these site-specific neurotransmitters, which may be related to the behavioural changes found in the HDC-deficient animals.
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Synthesis and characterization of organic–inorganic hybrid mesoporous silica materials with new templates. Chem Commun (Camb) 2004:240-1. [PMID: 14737568 DOI: 10.1039/b312178j] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
1-Hexadecane-3-methylimidazolium bromide and 1-hexadecane-2,3-dimethylimidazolium bromide were used as new templates for the syntheses of periodic mesoporous organosilica (PMO) materials; using these new templates, ethane-bridged PMO materials were successfully synthesized and characterized under basic conditions.
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Abstract
29Si NMR, small-angle X-ray scattering (SAXS), and dynamic light scattering (DLS) are used to monitor the synthesis of silica nanoparticles from the base-catalyzed hydrolysis of TEOS in methanol and ethanol. The reactions are conducted at a [TEOS] =0.5 M, low concentrations of ammonia ([NH(3)] =0.01-0.1 M), and [H(2)O] =1.1-4.4 M to resolve the initial size of the first nuclei and to follow their structural evolution. It is found that after an induction period where there is a buildup of singly hydrolyzed monomer, the first nuclei are fractal and open in structure. Interestingly, the nuclei are twice as large in ethanol (R(g) approximately 8 nm) as those in methanol (R(g) approximately 4 nm). The data suggest that the difference in primary particle size is possibly caused by a higher supersaturation ratio of the singly hydrolyzed monomer in methanol than in ethanol if it is assumed that the surface energy of the first nuclei is the same in methanol and ethanol. The particle number concentration and the volume fraction of the silica particles are calculated independently from the SAXS, DLS, and 29Si NMR results. Finally, the rate of nucleation is obtained from the particle number concentrations.
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Waking selective neurons in the posterior hypothalamus and their response to histamine H3-receptor ligands: an electrophysiological study in freely moving cats. Behav Brain Res 2003; 144:227-41. [PMID: 12946612 DOI: 10.1016/s0166-4328(03)00091-3] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Neurons which discharge selectively during waking (waking selective) have been found in the tuberomamillary nucleus (TM) and adjacent areas of the posterior hypothalamus. Although they share some electrophysiological properties with aminergic neurons, there is no direct evidence that they are histaminergic. We have recorded from posterior hypothalamic neurons during the sleep-wake cycle in freely moving cats, and investigated the effects on waking selective neurons of specific ligands of histaminergic H3-receptors, which autoregulate the activity of histaminergic neurons. Two types of neurons were seen. Waking selective neurons, termed "waking-on (W-on)," were located exclusively within the TM and adjacent areas, and discharged at a low regular rate during waking (1.71-2.97 Hz), decreased firing during light slow wave sleep (SWS), became silent during deep SWS and paradoxical sleep (PS) and resumed their activity on, or a few seconds before, awakening. "Waking-related" neurons, located in an area dorsal to the TM, displayed a similar, although less regular, low rate of firing (1.74-5.41 Hz) and a similar discharge profile during the sleep-wake cycle; however, unlike "W-on" neurons, they did not completely stop firing during deep SWS and PS. Intramuscular (i.m.) injection of ciproxifan (an H3-receptor antagonist, 1mg/kg), significantly increased the discharge rate of W-on neurons and induced c-fos expression in histamine-immunoreactive neurons, whereas i.m. injection of imetit (an H3-receptor agonist, 1mg/kg) or microinjection of alpha-methylhistamine (another H3-receptor agonist, 0.025-0.1 microg/0.2 microl) in the vicinity of these cells significantly decreased their discharge rate. Moreover, the effect of the antagonist was reversed by the agonists and vice versa. In contrast, "waking-related" neurons were unaffected by these H3-receptor ligands. These data provide evidence for the histaminergic nature of "W-on" neurons and their role in cortical desynchronization during waking, and highlight the heterogeneity of posterior hypothalamic neuronal populations, which might serve different functions during the wakefulness.
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Production of biologically active tethered ovine FSHbetaalpha by the methylotrophic yeast Pichia pastoris. J Mol Endocrinol 2003; 30:213-25. [PMID: 12683944 DOI: 10.1677/jme.0.0300213] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The pituitary-derived glycoprotein hormone FSH plays a central role in controlling vertebrate gonadal function. In female mammals the maturation of ovarian follicles is critically dependent upon stimulation by FSH. Moreover, injection of exogenous FSH is used extensively to stimulate increased numbers of follicles to ovulate. Structurally FSH is a heterodimeric glycoprotein composed of two non-covalently associated polypeptide subunits. The tertiary structures of both the alpha- and beta-subunits are constrained by intramolecular disulphide bonds and are post-translationally modified with two N-linked carbohydrate moieties, the structure of which appears to modulate in vivo biological activity. Here we report the expression of ovine FSH (oFSH) as a biologically active single-chain polypeptide using the methylotrophic yeast Pichia pastoris. Sequences encoding the mature oFSH alpha- and beta-proteins were fused to form a gene encoding a fusion protein with the C-terminus of the beta-chain joined to the N-terminus of the alpha-chain, with the chains separated by a two amino acid linker sequence. This fusion gene was itself fused to two alternative Pichia leader sequences (mating factor alpha and acid phosphatase) and transformed into the Pichia strains GS115 and SMD1168. The recombinant fusion protein (oFSHbetaalpha) was expressed at approximately 0.1 microg/ml in 'shake-flask' cultures. The Pichia-expressed tethered protein was biologically active in an in vitro bioassay, had a molecular mass of 28 kDa, as determined by SDS-PAGE, and bound the bovine FSH receptor with a binding profile similar to that of native oFSH.
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Homogeneity of a supersaturated solid solution. PHYSICAL REVIEW LETTERS 2002; 89:125507. [PMID: 12225100 DOI: 10.1103/physrevlett.89.125507] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2002] [Indexed: 05/23/2023]
Abstract
Extended x-ray absorption fine structures, small-angle x-ray scattering, and atomistic model calculations have been employed to probe the homogeneity of the fcc solution created in Ag-Cu, a classical system demonstrating the extension of solubility across the entire miscibility gap through rapid quenching. Our results reveal that in many cases the supersaturated solutions formed have decomposition features on the scale of 1 nm. Conventional diffraction methods are inadequate in determining the level of supersaturation or the uniformity of such solid solution alloys.
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Effects of huangqi jianzhong tang on hematological and biochemical parameters in judo athletes. Acta Pharmacol Sin 2001; 22:1154-8. [PMID: 11749817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
AIM The purpose of the study was to investigate the effects of Huangqi Jianzhong Tang (HQJZT) on hematological and biochemical parameters in judo athletes. METHODS Sixteen male and eight female judo athletes in Hsin-Ming senior high school were randomly and stratified divided into control and experimental group, which received placebo and HQJZT respectively during the five-week training program. The measurement of the hematological and biochemical parameters was performed twice, just before and after the training. The data was analyzed with paired-t test and ANOVA. RESULTS The values of RBC, Hb, and Hct were obvious decreased after intervention, while the value of GOT, GPT, BUN, and CK was elevated. CONCLUSION The results indicated the hematological and biochemical changes were caused by the physical training but not the effects of HQJZT. The HQJZT had no adverse effects on the judo athletes in our study.
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Propylthiouracil-induced hemolytic anemia. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 2001; 64:735-8. [PMID: 11922496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Propylthiouracil (PTU)-induced hemolytic anemia is extremely rare. We reported a case of Graves' disease with these unusual clinical manifestations. A 41-year-old female presented with recurrent attacks of severe hemolytic anemia after PTU therapy. Sugar water test and erythrocytes osmotic fragility test revealed no cellular membrane defect of red blood cells. Antinuclear antibody, direct and indirect Coombs' tests were all negative and glucose-6-phosphate dehydrogenase activity was also within normal limits. PTU was not discontinued promptly due to unrecognizableness of such a rare case until two months later with recurrent attacks of severe hemolytic anemia. 1-131 therapy was performed on suspicion of related hemolytic anemia. Unfortunately, challenge of PTU occurred incidentally after discontinuation of PTU followed by severe hemolytic anemia. The diagnosis of PTU-induced hemolytic anemia was established thereafter. A MEDLINE search revealed only one such case reported in English literature. This is the first case report in Taiwan. It should be kept in mind that hemolytic anemia may be a rare complication of PTU therapy.
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Catalytic nucleophilic acyl substitution of anhydrides by amphoteric vanadyl triflate. Org Lett 2001; 3:3729-32. [PMID: 11700124 DOI: 10.1021/ol016684c] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction--see text] Among four vanadyl species examined, vanadyl triflate was the most efficient catalyst to facilitate nucleophilic acyl substitution of anhydrides with a myriad array of alcohols, amines, and thiols in high yields and high chemoselectivity. By using mixed-anhydride technique, one can achieve oleate and peptide syntheses. In marked contrast to common metal triflates, the amphoteric character of the V=O unit in vanadyl species was proven to be responsible for the catalytic profile in this process.
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Expression patterns and transcript concentrations of the autosomal DAZL gene in testes of azoospermic men. Mol Hum Reprod 2001; 7:1015-22. [PMID: 11675467 DOI: 10.1093/molehr/7.11.1015] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The DAZ (Deleted in AZoospermia) gene cluster on the Y chromosome is a strong candidate for the azoospermia factor. The DAZ gene was derived from an autosomal homologue, DAZL (DAZ-Like). This study was designed to assess the functional role of DAZL in human spermatogenesis. The expression patterns and mRNA transcript levels of DAZL in the testes of 17 azoospermic men were therefore examined by immunohistochemical staining and quantitative competitive reverse transcription-polymerase chain reaction. DAZL protein was expressed in the cytoplasm of primary spermatocytes and weakly in spermatogonia. It was detected in the testicular tissues of all subjects with germ cells present. The copy number of the DAZL transcript in normal spermatogenesis (n = 4), hypospermatogenesis or maturation arrest (n = 6), and Sertoli cell-only syndrome (n = 7) ranged from 1.22 x 10(6) to 1.63 x 10(6) per ng of RNA, 1.19 x 10(5) to 2.82 x 10(5) per ng of RNA and 2.83 x 10(4) to 1.23 x 10(5) per ng of RNA respectively. DAZL transcripts were lower in men with spermatogenic failure, and a significant difference was found between the three groups (P < 0.0001). This study suggests that DAZL may play an important role in the human spermatogenic processes of both mitosis and meiosis.
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Effects of a hemoglobin-based oxygen carrier (HBOC-201) on coagulation testing. CLINICAL LABORATORY SCIENCE : JOURNAL OF THE AMERICAN SOCIETY FOR MEDICAL TECHNOLOGY 2001; 13:210-4. [PMID: 11586506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Polymerized bovine hemoglobin (HBOC-201) is currently under investigation as an alternative to blood banked human red cells. Due to the dark red, hemolyzed appearance of HBOC-201, we sought to describe the effects of HBOC-201 on coagulation analyzers that perform prothrombin times (PT), activated partial thromboplastin times, fibrinogen, and antithrombin. Pooled normal plasma was combined with HBOC-201 to achieve plasma hemoglobin levels of 1.4, 2.6 3.8, 4.8, and 6.2 g/dL. Results for each test from HBOC-201 prepared plasmas were compared to saline matched controls. Two consecutive absolute result differences of > 10% between saline controls and HBOC-201 samples were used for determining interference on test accuracy by the concentration of HBOC-201. Mechanical detection methods (fibrometer, STA, CS-190) and the MDA-180 were less affected by increasing levels of HBOC-201 than optical detection devices for all test parameters.
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Inner ear localization of mRNA and protein products of COCH, mutated in the sensorineural deafness and vestibular disorder, DFNA9. Hum Mol Genet 2001; 10:2493-500. [PMID: 11709536 DOI: 10.1093/hmg/10.22.2493] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Missense mutations in the COCH gene, which is expressed preferentially at high levels in the inner ear, cause the autosomal dominant sensorineural deafness and vestibular disorder, DFNA9 (OMIM 601369). By in situ hybridization of mouse and human inner ear sections, we find high-level expression of COCH mRNA in the fibrocytes of the spiral limbus and of the spiral ligament in the cochlea, and in the fibrocytes of the connective tissue stroma underlying the sensory epithelium of the crista ampullaris of the semicircular canals. A polyclonal antibody against the human COCH protein product, cochlin, was raised against the N-terminal 135 amino acid residues of cochlin, corresponding to the Limulus factor C-homology (cochFCH) domain; this domain harbors all five known point mutations in DFNA9. On western blots of human fetal cochlear extracts, anti-cochlin reacts with a cochlin band of the predicted full-length size as well as a smaller isoform. Immunohistochemistry performed with anti-cochlin shows staining predominantly in the regions of the fibrocytes of the spiral limbus and of the spiral ligament in mouse and in human fetal and adult tissue sections. These sites correspond to those areas that express COCH mRNA as determined by in situ hybridization, and to the regions of the inner ear which show histological abnormalities in DFNA9. The fibrocytes expressing mRNA and protein products of COCH are the very cell types which are either absent or markedly reduced and replaced by eosinophilic acellular material in temporal bone sections of individuals affected with DFNA9.
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MESH Headings
- Adult
- Animals
- Antibodies, Monoclonal/immunology
- Blotting, Western
- Ear, Inner/chemistry
- Ear, Inner/embryology
- Ear, Inner/metabolism
- Extracellular Matrix Proteins
- Gene Expression
- Gene Expression Regulation, Developmental
- Hearing Loss, Sensorineural/genetics
- Hearing Loss, Sensorineural/metabolism
- Hearing Loss, Sensorineural/pathology
- Humans
- Immunohistochemistry
- In Situ Hybridization
- Mice
- Mutation
- Proteins/genetics
- Proteins/immunology
- Proteins/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Tissue Distribution
- Vestibular Diseases/genetics
- Vestibular Diseases/metabolism
- Vestibular Diseases/pathology
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Distinct CD8 T cell functions mediate susceptibility to histoplasmosis during chronic viral infection. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:4566-73. [PMID: 11591785 DOI: 10.4049/jimmunol.167.8.4566] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
It has long been recognized that some viral infections result in generalized immune suppression. In acute infections, this period of suppressed immunity is relatively short. However, chronic infections associated with a prolonged period of immune suppression present far greater risks. Here, we examined the role of CD8 T cell responses following viral infection in immunity to systemic histoplasmosis. Although wild-type mice with systemic histoplasmosis were able to control the infection, those simultaneously infected with lymphocytic choriomeningitis virus clone 13 showed reduced immunity with greater fungal burden and high mortality. The immune suppression was associated with loss of CD4 T cells and B cells, generalized splenic atrophy, and inability to mount a granulomatous response. Removing the anti-viral CD8 T cells in the coinfected mice enabled them to reduce the fungal burden and survive the infection. Their lymphoid organs were replenished with CD4 T and B cells. In contrast to wild-type mice, perforin-deficient mice infected with lymphocytic choriomeningitis virus clone 13 and Histoplasma showed an absence of immunopathology, but the animals still died. These results show that CD8 T cells can suppress immunity through different mechanisms; although immunopathology is perforin-dependent, lethality is perforin-independent.
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Abstract
This study characterized the VX2 bladder cancer model in rabbits and tested the feasibility of treating bladder cancer by extravesical cryosurgery. After the growth characteristics of the VX2 bladder tumor model were determined, the VX2 tumor was inoculated into rabbits at the dome of the bladder. One week later, three freeze/thaw cycles were followed by immediate surgical repair. The control group underwent a sham operation without freezing. When the VX2 tumor is injected into the bladder wall, invasion and central necrosis occurred within I week, lymphatic metastases by 2 weeks, and lung metastases by 3 weeks after inoculation. By 4 weeks, all control rabbits had large VX2 tumors in their bladders and advanced lung metastases. Nine of the ten rabbits in the cryosurgical group had mild to moderate degrees of lung metastases, and six of them had relatively small local recurrences. One rabbit had no tumor in the bladder and only microscopic lung metastasis. The extravesical approach to cryosurgery employing bladder inversion is well tolerated. Cryosurgery exhibits modest efficacy in treating local tumors and delaying lung metastasis in this aggressive tumor model.
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Bioinformatics and mass spectrometry for microorganism identification: proteome-wide post-translational modifications and database search algorithms for characterization of intact H. pylori. Anal Chem 2001; 73:4566-73. [PMID: 11605832 DOI: 10.1021/ac010466f] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
MALDI-TOF mass spectrometry has been coupled with Internet-based proteome database search algorithms in an approach for direct microorganism identification. This approach is applied here to characterize intact H. pylori (strain 26695) Gram-negative bacteria, the most ubiquitous human pathogen. A procedure for including a specific and common posttranslational modification, N-terminal Met cleavage, in the search algorithm is described. Accounting for posttranslational modifications in putative protein biomarkers improves the identification reliability by at least an order of magnitude. The influence of other factors, such as number of detected biomarker peaks, proteome size, spectral calibration, and mass accuracy, on the microorganism identification success rate is illustrated as well.
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