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Salamah MA, Kotb AN, El Deen SS, Hegab MA. Pigtail with self-retaining bicanalicular intubation combined with Mitomycin C for the treatment of acquired lower punctal stenosis. Int Ophthalmol 2024; 44:224. [PMID: 38744721 DOI: 10.1007/s10792-024-03146-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 04/11/2024] [Indexed: 05/16/2024]
Abstract
BACKGROUND The pigtail was used to create an opening at the lower punctal site in grade 0 stenosis with insertion of self-retaining tube and Mitomycin C (MMC). METHODS The patients with acquired lower punctal stenosis (grade 0) were divided randomly into equal groups, Group A: were treated with pigtail and MMC 0.02% and Group B: were treated with pigtail alone. The pigtail was inserted through the upper punctum until its tip reached the occluded punctum, this site was incised with a scalpel (No. 11). A self-retaining bicanalicular tube was then placed. RESULTS Results of 36 eyes from 26 patients were included. No differences were observed between both groups regarding epiphora score, FDD test and punctal size preoperatively. The postoperative epiphora score, there were significant differences at 1 month (P = 0.035), 3 months (P = 0.005), and 6 months after removal (P < 0.001). The FDD test, there were significant differences at 6 months (P = 0.045), 1 month (P = 0.021), 3 months (P = 0.012), and 6 months post tube removal (P = 0.005). The punctal size, both groups differed at 1 month (P = 0.045), 3 months (P = 0.03), and 6 months post tube removal (P = 0.005). Only one case (5.5%) at each group showed extrusion of the tube. CONCLUSION The pigtail probe, bicanalicular stent and MMC can be an effective method in treatment of severe punctal stenosis.
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Sharma R, Gupta S, Rathore AS. Novel purification platform based on multimodal preparative scale separation of mAb fragments and aggregates. J Chromatogr A 2024; 1721:464806. [PMID: 38518514 DOI: 10.1016/j.chroma.2024.464806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/21/2024] [Accepted: 03/06/2024] [Indexed: 03/24/2024]
Abstract
Monoclonal antibodies (mAbs) continue to dominate the biopharmaceutical industry. Certain mAbs are prone to fragmentation and clipping and in these cases, adequate removal of these species is critical during manufacturing. Fragments can be generated during fermentation, purification, storage, formulation, and administration. Their addition to the acidic charge-variant of the purified mAb has been reported to decrease stability and potency of the final product. However, contrary to mAb aggregation, manufacturers have not given much attention to removal of fragments and clipped species and as a result most conventional mAb platforms offer at best limited capabilities for their removal. In this study, we propose a novel purification platform that uses multimodal chromatography and achieves complete removal of a range of mAb fragments and clipped products (25-120 kDa). The utility of the platform has been successfully demonstrated for 2 IgG1s and 2 IgG4s. Further, adequate removal of the various host cell impurities such as host cell proteins (<10 ppm) and host cell DNA (<5 ppb) has been achieved. Finally, the platform was able to deliver adequate removal of high molecular weight impurities (<1 %) and a 30 % clearance of the acidic charge variant. The proposed single step has been shown to deliver what the polishing chromatography and intermediate purification chromatography steps deliver in a traditional mAb platform.
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Radović Jakovljević M, Grujičić D, Stanković M, Milošević-Djordjević O. Artemisia vulgaris L., Artemisia alba Turra and their constituents reduce mitomycin C-induced genomic instability in human peripheral blood lymphocytes in vitro. Drug Chem Toxicol 2024; 47:156-165. [PMID: 36476306 DOI: 10.1080/01480545.2022.2154358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 11/23/2022] [Accepted: 11/27/2022] [Indexed: 12/13/2022]
Abstract
This study aimed to evaluate the effect of aqueous and acetone extracts from Artemisia vulgaris L. (AV) and Artemisia alba Turra (AA), and two major polyphenols compounds (3,5-dihydroxybenzoic acid and quercetin-3-O-glucopyranoside) presented in both extracts of the plants against mitomycin C (MMC)-induced genomic instability. Genomic instability was measured using cytokinesis block micronucleus (MN) assay in human peripheral blood lymphocytes (PBLs) in vitro by analyzing two biomarkers - MN and nuclear division index (NDI). Extracts were tested in a concentration-dependent manner (10-250 µg/mL), while 3,5-dihydroxybenzoic acid and quercetin-3-O-glucopyranoside were tested in three different concentrations, in combination with 0.5 µg/mL of MMC. Aqueous and acetone extracts obtained from both plants significantly reduced MMC-induced MN frequency in PBLs, compared to positive control cells (p < 0.05). Extracts from AV did not affect NDI, whereas the concentrations of 10-100 μg/mL of aqueous and acetone AA extracts significantly elevated MMC-decreased NDI values in comparison to positive control cells (p < 0.05). Combined treatment of 3,5-dihydroxybenzoic acid and MMC showed a significant reduction of MMC-induced MN frequency, while quercetin-3-O-glucopyranoside increased MN frequency compared to positive control cells (p < 0.05). Both compounds decreased NDI values but only at the highest tested concentration of quercetin-3-O-glucopyranoside it was of greater significance. In conclusion, all extracts from AV and AA and 3,5-dihydroxybenzoic acid showed protective effect, whereby aqueous AA demonstrated the highest protective effect on MMC- induced genomic instability, while quercetin-3-O-glucopyranoside showed co-mutagen effect.
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Palmer EL, Forsythe S. A document analysis of the South African national guidelines for medical male circumcision and the implications for infant and child male circumcision decision-making. AFRICAN JOURNAL OF AIDS RESEARCH : AJAR 2023; 22:327-333. [PMID: 38117746 DOI: 10.2989/16085906.2023.2277889] [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: 07/01/2023] [Accepted: 10/01/2023] [Indexed: 12/22/2023]
Abstract
South Africa's 2016 medical male circumcision (MMC) guidelines ("the guidelines") provide direction for the MMC programme's implementation in South Africa. The aim of our document analysis was to assess the guidelines, particularly in lieu of changing guidance from WHO and PEPFAR. We then assessed how the guidelines might be applied to infant and child male circumcision (ICMC). The analysis was performed by reviewing South Africa's guidelines, along with international documents used in developing those guidelines, to identify the historical development of the guidelines, as well as the implications for MMC and ICMC decision-making within the South African context. The following principles were analysed within the context of South Africa's guidelines: (1) quality and safety; (2) informed consent; (3) confidentiality; (4) human rights; and (5) accessibility of services. Tthe document analysis also identified ambiguities that exist in the guidelines, particularly regarding consent, recognising religious or cultural exemptions, and guaranteeing the best interests of the child. South Africa's MMC guidelines could benefit from incorporating common definitions to assist with interpretation and understanding, thus preventing confusion and controversy among programme planners, parents and boys. The guidelines were made available in 2016 and recommendations for circumcision have evolved as new research and information has become available. South Africa's National Department of Health should review and update these guidelines, with a focus on both MMC and ICMC issues, so that they reflect the most up-to-date, accurate information available, to avoid inconsistent practices, risks, and litigation in the management of the programme. This study was situated within a qualitative paradigm and applied a social choice theory perspective to make sense of the MMC guidelines. The study concludes that future policy revisions should develop a broader understanding of the complex medical male circumcision decision-making process, particularly faced by parents.
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Arish M, Sargazi M, Dehghani S, Sahami M, Dashipour A, Sarhadi S, Rouientan H. Long-term effects of intraoperative topical bevacizumab in sutureless scleral tunnel trabeculectomy: a prospective clinical trial. Int Ophthalmol 2023; 43:4225-4233. [PMID: 37561247 DOI: 10.1007/s10792-023-02833-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 07/27/2023] [Indexed: 08/11/2023]
Abstract
PURPOSE To investigate the long-term efficacy and safety of the novel method sutureless trabeculectomy with topical administration of bevacizumab. MATERIALS/METHODS Primary open-angle glaucoma patients with intraocular pressure (IOP) > 21 mmHg despite maximum tolerated medication were included in a single-blind prospective interventional clinical trial. Group 1 underwent sutureless scleral tunnel trabeculectomy with intraoperative topical administration of bevacizumab (1.25 mg) applied on the scleral incision for 1 min. Group 2 underwent sutureless trabeculectomy alone and group 3 (control group) underwent conventional trabeculectomy with mitomycin C (MMC). Outcome measures were surgical success, IOP, number of needed anti-glaucoma medications, and complications. Patients were followed for two years. RESULTS Finally, 50 eyes from group 1, 46 from group 2, and 47 from group 3 were analyzed. At the end of 24 months, 52% (n = 26) of group 1, 34.8% (n = 16) of group 2, and 57.4% (n = 27) of group 3 had complete success (IOP < 18 mmHg without medication). The difference was only significant between groups 2 and 3 (p = 0.003). 94% (n = 47) of group 1, 89.1% (n = 41) of group 2, and 91.5% (n = 43) of group 3 had qualified success (IOP < 18 mmHg with ≤ 2 anti-glaucoma medications) (p = 0.69). There was a significant difference in the overall IOP mean between the three groups (p < 0.0001). There was no significant difference between the three groups in complication rates and the number of needed anti-glaucoma medications for IOP control. CONCLUSION Sutureless trabeculectomy with topical application of bevacizumab showed comparable surgical success rates with conventional trabeculectomy and MMC in long-term follow-up. Additionally, adjuvant use of topical bevacizumab had a significant positive impact on long-term IOP control.
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Gopal PM, Kavimani V, Gupta K, Marinkovic D. Laser-Based Manufacturing of Ceramics: A Review. MICROMACHINES 2023; 14:1564. [PMID: 37630099 PMCID: PMC10456894 DOI: 10.3390/mi14081564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 08/27/2023]
Abstract
Ceramics are widely used in microelectronics, semiconductor manufacturing, medical devices, aerospace, and aviation, cutting tools, precision optics, MEMS and NEMS devices, insulating components, and ceramic molds. But the fabrication and machining of the ceramic-based materials by conventional processes are always difficult due to their higher hardness and mechanical properties. Therefore, advanced manufacturing techniques are being preferred for these advanced materials, and out of that, laser-based processes are widely used. The benefits of laser fabrication and machining of ceramics include high precision, reduced thermal damage, non-contact processing, and the ability to work with complex geometries. Laser technology continues to advance, enabling even more intricate and diverse applications for ceramics in a wide range of industries. This paper explains various laser based ceramic processing techniques, such as selective laser sintering and melting, and laser machining techniques, such as laser drilling, etc. Identifying and optimizing the process parameters that influence the output quality of laser processed parts is the key technique to improving the quality, which is also focused on in this paper. It aims to facilitate the researchers by providing knowledge on laser-based manufacturing of ceramics and their composites to establish the field further.
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Alexander-Savino CV, Morrell DS, Mervak JE, Bowers EV. Characteristics of Dermatology Residency Program Morbidity and Mortality Conferences: A Survey of Program Directors. JMIR DERMATOLOGY 2023; 6:e45194. [PMID: 37632923 PMCID: PMC10425815 DOI: 10.2196/45194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 06/08/2023] [Accepted: 07/14/2023] [Indexed: 08/28/2023] Open
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Bartonek Å, Eriksson M. Physical function and activity, pain, and health status in adults with myelomeningocele after orthotic management from childhood: a descriptive study. BMC Musculoskelet Disord 2023; 24:545. [PMID: 37400860 DOI: 10.1186/s12891-023-06673-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 06/28/2023] [Indexed: 07/05/2023] Open
Abstract
BACKGROUND Individuals with myelomeningocele (MMC) exhibit neurological deficits below the lesion level involving both motor and sensory functions. Ambulation and functional outcomes in patients offered orthotic management since childhood were investigated. METHODS Physical function, physical activity, pain, and health status were assessed in a descriptive study. RESULTS Of 59 adults with MMC, aged 18-33 years, 12 were in the community ambulation (Ca), 19 in the household ambulation (Ha), six in the non-functional (N-f), and 22 in the non-ambulation (N-a) groups. Orthoses were used by 78% (n = 46), i.e., by 10/12 in the Ca, 17/19 in the Ha, 6/6 in the N-f, and 13/22 in the N-a groups. In the ten-metre walking test, the non-orthosis group (NO) walked faster than those wearing ankle-foot orthoses (AFOs) or free-articulated knee-ankle-foot orthoses (KAFO-Fs), the Ca group faster than the Ha and N-f groups, and the Ha group faster than the N-f group. In the six-minute walking test, the Ca group walked farther than the Ha group. In the five times sit-to-stand test, the AFO and KAFO-F groups required longer than the NO group, and the KAFO-F group longer than the foot orthosis (FO) group. Lower extremity function with orthoses was higher in the FO than the AFO and KAFO-F groups, higher in the KAFO-F than the AFO group, and higher in the AFO group than in those using trunk-hip-knee-ankle-foot orthoses. Functional independence increased with ambulatory function. Time spent in physical recreation was higher in the Ha than the Ca and N-a groups. There were no differences between the ambulation groups in rated pain or reported health status. CONCLUSION The physical function results in persons with MMC improve our understanding of this population's heterogeneity and shed light on the importance of individualized orthotic management. The similarities between the various ambulatory levels in physical activity, pain, and health status may mirror opportunities to achieve equal results regardless of disability level. A clinical implication of the study is that orthotic management is likely to be beneficial for the patient with MMC of which the majority used their orthoses for most time of the day.
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Riquelme-Neira R, Walker-Vergara R, Fernández-Blanco JA, Vergara P. IL-10 Modulates the Expression and Activation of Pattern Recognition Receptors in Mast Cells. Int J Mol Sci 2023; 24:9875. [PMID: 37373041 DOI: 10.3390/ijms24129875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/25/2023] [Accepted: 05/30/2023] [Indexed: 06/29/2023] Open
Abstract
Mast cells (MCs) are involved in several immune-related responses, including those in bacterial infections, autoimmune diseases, inflammatory bowel diseases, and cancer, among others. MCs identify microorganisms by pattern recognition receptors (PRRs), activating a secretory response. Interleukin (IL)-10 has been described as an important modulator of MC responses; however, its role in PRR-mediated activation of MC is not fully understood. We analyzed the activation of TLR2, TLR4, TLR7 and Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) in mucosal-like MCs (MLMCs) and peritoneum-derived cultured MCs (PCMCs) from IL-10-/- and wild-type (WT) mice. IL-10-/- mice showed a reduced expression of TLR4 and NOD2 at week 6 and TLR7 at week 20 in MLMC. In MLMC and PCMC, TLR2 activation induced a reduced secretion of IL-6 and TNFα in IL-10-/- MCs. TLR4- and TLR7-mediated secretion of IL-6 and TNFα was not detected in PCMCs. Finally, no cytokine release was induced by NOD2 ligand, and responses to TLR2 and TLR4 were lower in MCs at 20 weeks. These findings indicate that PRR activation in MCs depends on the phenotype, ligand, age, and IL-10.
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Ali K, Wendt K, Sorkhabi MM, Benjaber M, Denison T, Rogers DJ. xTMS: A Pulse Generator for Exploring Transcranial Magnetic Stimulation Therapies. CONFERENCE PROCEEDINGS. IEEE APPLIED POWER ELECTRONICS CONFERENCE AND EXPOSITION 2023; 2023:1875-1880. [PMID: 37342241 PMCID: PMC7614672 DOI: 10.1109/apec43580.2023.10131554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/22/2023]
Abstract
A cascaded H-bridge based pulse generator for transcranial magnetic stimulation is introduced. The system demonstrates complete flexibility for producing different shape, duration, direction, and rate of repetition of stimulus pulses within its electrical limits, and can emulate all commercial and research systems available to-date in this application space. An offline model predictive control algorithm, used to generate pulses and sequences, shows superior performance compared to conventional carrier-based pulse width modulation. A fully functioning laboratory prototype delivers up to 1.5 kV, 6 kA pulses, and is ready to be used as a research tool for the exploration of transcranial magnetic stimulation therapies by leveraging the many degrees-of-freedom offered by the design.
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Wu P, Wang Z, Liang L, Chen B, Xu N. Characteristics of Mitomycin C-Loaded Peptide Hydrogel In Vitro and Antiscarring Effects in Rat Ocular Injury Model. J Ocul Pharmacol Ther 2023; 39:139-147. [PMID: 36724493 DOI: 10.1089/jop.2022.0102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Purpose: To investigate the characteristics of sustained drug release systems established by an arginine-glycine-aspartic acid (RGD) peptide hydrogel and mitomycin C (MMC) in vitro, and verify their antiscar effects in rat ocular injury model. Methods: Low, medium, and high loading doses of MMC were added to 5 mL 0.25%, 0.5%, and 1% wt RGD peptide hydrogel, respectively, to prepare 9 ratios of MMC-RGD systems. Drug release characteristics of the systems in phosphate-buffered saline solution were investigated by plotting the drug release curves and fitting them with mathematical models in OriginPro8.0 software. Appropriate ratios of MMC-RGD systems were selected as treatment in rat ocular injury model. Scar formation was observed by Masson staining and immunohistochemical staining with alpha-smooth muscle actin (α-SMA) and fibronectin (FN). Results: Nine ratios of MMC-RGD systems could release drug slowly. The maximum drug release proportions of all systems were >80%, and the time to maximum release proportions statistically prolonged with the increase of drug loading. Fitting with mathematical models indicated that the mechanisms of drug release were mainly Fick diffusion at early stage and Anomalous Transport at later stage. Systems of 1% wt RGD hydrogel were evaluated in animal experiments, which could inhibit hyperplasia of collagen and expression of α-SMA and FN. Conclusions: The RGD peptide hydrogel could be used as the carrier of MMC to establish sustained drug release system, which could inhibit scar formation after rat's ocular injury.
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Upaphong P, Pathanapitoon K, Chaidaroon W. Inadvertent filtering bleb due to extracapsular cataract extraction wound reopening after mitomycin C use: a case report. J Med Case Rep 2023; 17:57. [PMID: 36800977 PMCID: PMC9938554 DOI: 10.1186/s13256-023-03784-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 01/19/2023] [Indexed: 02/19/2023] Open
Abstract
BACKGROUND Mitomycin C has been used adjunctively in various procedures, including pterygium excision. Delayed wound healing, the long-term complication of mitomycin C, can occur several years later and may rarely cause a subsequent inadvertent filtering bleb. However, conjunctival bleb formation from the reopening of an adjacent surgical wound after mitomycin C use has not been reported. CASE PRESENTATION A 91-year-old Thai woman had undergone pterygium excision 26 years ago, with adjunctive mitomycin C, as well as an uneventful extracapsular cataract extraction in the same year. The patient developed a filtering bleb without glaucoma surgery or trauma approximately 25 years later. Anterior segment ocular coherence tomography illustrated a fistula connected between the bleb and anterior chamber at the scleral spur. The bleb was observed without further management, as no hypotony or bleb-related complications occurred. The symptoms/signs of bleb-related infection were advised. CONCLUSIONS This is a case report of a rare novel complication of mitomycin C application. Conjunctival bleb formation from the reopening of surgical wound, which was related to the previous mitomycin C use, could occur after a few decades.
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Wylegala A, Sripawadkul W, Zein M, Alvarez OP, Al Bayyat G, Galor A, Karp CL. Topical 1% 5-fluorouracil eye drops as primary treatment for ocular surface squamous neoplasia: Long-term follow-up study. Ocul Surf 2023; 27:67-74. [PMID: 36476665 DOI: 10.1016/j.jtos.2022.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 11/25/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
PURPOSE To determine the efficacy and safety of topical 1% 5-fluorouracil (5FU) eye drops as primary treatment of ocular surface squamous neoplasia (OSSN). METHODS Patients were diagnosed with OSSN based on slit-lamp examination and anterior segment optical coherence tomography (AS-OCT). In ambiguous cases an incisional biopsy was performed. All were treated with 5FU eye drops as primary therapy and retrospectively reviewed. Data on demographics, tumor characteristics, treatment outcome, and side effects were collected. The primary outcome measures were resolution frequency and recurrence rate of OSSN. Secondary outcomes were risk factors for resolution and recurrence, and side effects of treatment. RESULTS The mean age of 251 subjects (258 eyes) was 67.5 ± 11.7 years, 182 were male. Patients were followed up on average for 752 ± 580 days. Overall, 87% of patients experienced complete tumor resolution. Multivariable analysis revealed that superior tumor location (HR: 0.62, 95% CI: 0.41-0.93, p = 0.02) and leukoplakia (HR: 0.65, 95% CI: 0.41-0.93, p = 0.02), decreased the likelihood of tumor resolution. The recurrence rate was 4% at six months, 8% at one year, and 19% at two years. Larger tumor area increased chances of tumor recurrence (HR: 1.01, 95% CI: 1.00-1.02 p = 0.03). The most common side effects of 5-FU were mild hyperemia and pain, which occurred in 26% and 23% of patients, respectively. Among the sight-threatening side effects, limbal stem cell deficiency occurred in only 3% of patients. CONCLUSIONS Topical 1% 5FU eye drops are a safe and effective medication for OSSN. Superior tumor location and leukoplakia decreased the chance of tumor resolution.
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Tavakoli SD, Prieto-Araujo E, Sánchez-Sánchez E, Gomis-Bellmunt O. Methodology for interaction identification in modular multi-level converter-based HVDC systems. ISA TRANSACTIONS 2022; 126:300-315. [PMID: 34334180 DOI: 10.1016/j.isatra.2021.07.034] [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: 11/29/2020] [Revised: 07/20/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
This paper suggests a methodology for the identification, classification, and evaluation of various types of interactions that may occur in an HVDC link based on modular multi-level converters (MMC). The methodology incorporates the most suitable analytic tools for the frequency-domain study of each interaction category. To do so, a detailed nonlinear model of an MMC-based HVDC link that consists of master and slave MMCs, AC grids, and the DC transmission system is derived. Then, it is linearized to obtain a multi-input multi-output (MIMO) linear model that represents the dynamics of the complete MMC-based HVDC link. Based on the control loops of interest, interactions are classified as (1) state variable interactions, (2) disturbance interactions, (3) control loop interactions, and (4) overall system interactions. Then, through the application examples, the mentioned four categories of interactions are studied in frequency domain via the relevant analytic tools. The results obtained from the frequency-domain analysis are validated by time-domain simulation.
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Rahaman M, Zahn DRT. Plasmon-enhanced Raman spectroscopy of two-dimensional semiconductors. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:333001. [PMID: 35671747 DOI: 10.1088/1361-648x/ac7689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 06/07/2022] [Indexed: 06/15/2023]
Abstract
Two-dimensional (2D) semiconductors have grown fast into an extraordinary research field due to their unique physical properties compared to other semiconducting materials. The class of materials proved extremely fertile for both fundamental studies and a wide range of applications from electronics/spintronics/optoelectronics to photocatalysis and CO2reduction. 2D materials are highly confined in the out-of-plane direction and often possess very good environmental stability. Therefore, they have also become a popular material system for the manipulation of optoelectronic properties via numerous external parameters. Being a versatile characterization technique, Raman spectroscopy is used extensively to study and characterize various physical properties of 2D materials. However, weak signals and low spatial resolution hinder its application in more advanced systems where decoding local information plays an important role in advancing our understanding of these materials for nanotechnology applications. In this regard, plasmon-enhanced Raman spectroscopy has been introduced in recent time to investigate local heterogeneous information of 2D semiconductors. In this review, we summarize the recent progress of plasmon-enhanced Raman spectroscopy of 2D semiconductors. We discuss the current state-of-art and provide future perspectives on this specific branch of Raman spectroscopy applied to 2D semiconductors.
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Jiang T, Zheng B. Epigenetic Regulation of Megaspore Mother Cell Formation. FRONTIERS IN PLANT SCIENCE 2022; 12:826871. [PMID: 35185968 PMCID: PMC8850924 DOI: 10.3389/fpls.2021.826871] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 12/31/2021] [Indexed: 05/31/2023]
Abstract
In flowering plants, the female gametophyte (FG) initiates from the formation of the megaspore mother cell (MMC). Among a pool of the somatic cells in the ovule primordium, only one hypodermal cell undergoes a transition of cell fate to become the MMC. Subsequently, the MMC undergoes a series of meiosis and mitosis to form the mature FG harboring seven cells with eight nuclei. Although SPL/NZZ, the core transcription factor for MMC formation, was identified several decades ago, which and why only one somatic cell is chosen as the MMC have long remained mysterious. A growing body of evidence reveal that MMC formation is associated with epigenetic regulation at multiple layers, including dynamic distribution of histone variants and histone modifications, small RNAs, and DNA methylation. In this review, we summarize the progress of epigenetic regulation in the MMC formation, emphasizing the roles of chromosome condensation, histone variants, histone methylation, small RNAs, and DNA methylation.
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Palumbo F, Draga S, Vannozzi A, Lucchin M, Barcaccia G. Trends in Apomixis Research: The 10 Most Cited Research Articles Published in the Pregenomic and Genomic Eras. FRONTIERS IN PLANT SCIENCE 2022; 13:878074. [PMID: 35599856 PMCID: PMC9115752 DOI: 10.3389/fpls.2022.878074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/14/2022] [Indexed: 05/12/2023]
Abstract
Apomixis, or asexual reproduction by seed, represents an easy shortcut for life cycle renewal based on maternal embryo production without ploidy reduction (meiosis) and ploidy restitution (syngamy). Although the first studies officially published on this topic in scientific journals date back to the early 1930s, the identification and introduction of genes involved in asexual reproduction in species of agronomic interest still represent a major challenge. Through a bibliometric analysis of the research programs implemented in apomixis over the last 40 years, the present study was aimed to discuss not only the main findings achieved but also the investigational methods and model species used. We split the critical survey of the most cited original articles into pregenomic and genomic eras to identify potential trends and depict scenarios that have emerged in the scientific community working on apomixis, as well as to determine any correlation between the exponential increase in acquired basic knowledge and the development of advanced analytical technologies. This review found a substantial stagnation in the use of the same model species, with few exceptions, for at least 40 years. In contrast, the development of new molecular techniques, genomic platforms, and repositories has directly affected the approaches used in research, which has been directed toward an increasingly focused study of the genetic and epigenetic determinants of apomixis.
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Karakas C, Fidan E, Arya K, Webber T, Cracco JB. Frequency, Predictors, and Outcome of Seizures in Patients With Myelomeningocele: Single-Center Retrospective Cohort Study. J Child Neurol 2022; 37:80-88. [PMID: 34817276 DOI: 10.1177/08830738211053132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To determine the frequency, predictors, and outcomes of seizures in patients with myelomeningocele, we retrospectively analyzed the data from patients with myelomeningocele followed longitudinally at a single center from 1975 to 2013. We identified a total of 122 patients (61% female). The mean follow-up duration was 11.1 years (minimum-maximum = 0-34.5 years, SD = 8.8, median = 9.1 years). A total of 108 (88.5%) patients had hydrocephalus, and 98 (90.7%) of those patients required a ventriculoperitoneal shunt procedure. Twenty-four (19.7%) patients manifested with seizures, 23 of whom had hydrocephalus. The average age of seizure onset was 4.8 years (median 2 years of age). Falx dysgenesis (P = .004), lumbar myelomeningocele (P = .007), and cortical atrophy (P = .028) were significantly associated with epileptic seizure development. The average seizure-free period at the last follow-up in patients with a history of myelomeningocele and seizures was 8.1 years. We conclude that myelomeningocele patients with seizures have an overall good prognosis with considerable long-term seizure freedom.
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Mattout HK, Fouda SM, Al-Nashar HY. Evaluation of Topical Mitomycin-C Eye Drops After Reconstructive Surgery for Anophthalmic Contracted Socket. Clin Ophthalmol 2021; 15:4621-4627. [PMID: 34916774 PMCID: PMC8667192 DOI: 10.2147/opth.s343550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 11/18/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose To report the outcomes of using topical mitomycin-C (MMC) after reconstructive surgery for contracted socket and to compare the results with those of the conventional postoperative treatment. Patients and Methods The medical records of patients who underwent reconstructive surgery for contracted anophthalmic socket were retrospectively reviewed. Based on the postoperative treatment protocol, two groups of patients were identified; group I (15 patients) who received topical MMC drops (0.02%) 4 times daily for 6 weeks and group II (15 patients) who received the conventional treatment (topical antibiotic-steroid combination). Preoperative data were extracted for age, gender, cause and timing of anophthalmia, history of previous surgeries, preoperative forniceal depth and socket volume (SV). The main postoperative outcome measures were superior fornix depth (SFD), inferior fornix depth (IFD) and SV at the end of 6th postoperative month. Prosthesis fitting and complications were also considered for analysis. Results The mean preoperative IFD was 1.67±0.04 mm in group I and 1.58±0.37 mm in group II, by the end of the 6th postoperative month it increased to 6.1 ±0.27 mm and 5.12 ±0.25mm, respectively. The mean preoperative SFD in group I was 8.3±0.9 mm and 8.9±1.1 mm in group II, by the end of the 6th postoperative month SFD became 13.4±1.2 mm and 10.2±1.4 mm in groups I and II, respectively. The mean SV measured six months postoperatively was 1.9±0.2 mL and 1.3±0.09 mL in groups I and II, respectively. These differences in the postoperative SFD, IFD and SV between both groups were statistically significant. More cases reported successful fitting in group I than in group II but this difference was not statistically significant. Conclusion Postoperative use of topical MMC is associated with higher forniceal depth and greater SV when compared to the conventional treatment in socket reconstructive surgeries with amniotic membrane graft (AMG).
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Hamouda RA, Salman AS, Alharbi AA, Alhasani RH, Elshamy MM. Assessment of the Antigenotoxic Effects of Alginate and ZnO/Alginate-Nanocomposites Extracted from Brown Alga Fucus vesiculosus in Mice. Polymers (Basel) 2021; 13:polym13213839. [PMID: 34771394 PMCID: PMC8587912 DOI: 10.3390/polym13213839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 10/29/2021] [Accepted: 11/01/2021] [Indexed: 01/01/2023] Open
Abstract
Mitomycin C (MMC) is an alkylating chemotherapy drug that could induce DNA damage and genetic alteration. It has been used as a model mutagen for in vivo and in vitro studies. The current study aimed to evaluate the protective role of Zinc oxide alginate–nanocomposites (ZnO-Alg/NCMs) against MMC–induced genotoxicity in mice. Animals were treated as follows: the control group, the groups treated with Algin (400 mg/kg b.w), the groups treated with ZnO-Alg/NCMs (400 mg/kg b.w), the group treated with MMC, and the groups treated with MMC plus Algin or ZnO-Alg/NCMs. Pre-treatment with Algin and ZnO-Alg/NCMs was repeated for one or seven days. Zinc oxide alginate-nanocomposites (ZnO-Alg/NCMs) were synthesized with the aim of incorporating the intrinsic properties of their constituents as an antigenotoxic substance. In this study, alginate was extracted from the brown marine alga Fucus vesiculosus, Zinc oxide nanoparticles were synthesized by using water extract of the same alga, and loaded in alginate to synthesize ZnO-Alg/NCMs. ZnO-NPs and ZnO-Alg/NCMs were characterized by TEM, SEM, EDX, and Zeta potential. The obtained results confirmed that by TEM and SEM, ZnO-NPs are rod shaped which modified, when loaded in alginate matrix, into spherical shape. The physical stability of ZnO-Alg/NCMs was reported to be higher than ZnO-NPs due to the presence of more negative charges on ZnO-Alg/NCMs. The EDX analysis indicated that the amount of zinc was higher in ZnO-NPs than ZnO-Alg/NCMs. The in vivo results showed that treatment with MMC induced genotoxic disturbances. The combined treatment with Algin and ZnO-Alg/NCMs succeeded in inducing significant protection against MMC. It could be concluded that ZnO-Algin/NCMs is a promising candidate to protect against MMC–induced genotoxicity.
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Reimann H, Bankoglu EE, Stopper H, Hintzsche H. In vitro evaluation of chromosomal damage and DNA strand breaks after treatment with the poppy seed alkaloid thebaine. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2021; 870-871:503393. [PMID: 34583825 DOI: 10.1016/j.mrgentox.2021.503393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 08/15/2021] [Accepted: 08/17/2021] [Indexed: 11/25/2022]
Abstract
Thebaine is an alkaloid and can be found in poppy seeds in relatively high concentrations. Acute toxicity of thebaine is fairly high, but not much is known about chronic toxicity. To investigate the genotoxicity of thebaine, cytokinesis-block micronucleus test and comet assay were conducted in TK6 cells. In addition, effects of putative thebaine metabolites were analysed using metabolically active HepG2 cells and TK6 cells with S9 mix. FDA test and trypan blue test were used together with the frequency of mitotic and apoptotic cells to assess potential cytotoxicity of thebaine treatment. Micronucleus induction was observed after high doses (150 and 500 μM) of thebaine without metabolic activation in the presence of slight to moderate cytotoxicity. No effects were observed in the comet assay or after metabolic activation up to the highest dose of 500 μM. A potential protective effect on micronucleus induction after thebaine treatment was investigated via co-treatment with MMC and BaP in TK6 cells. Only after co-treatment with MMC, a reduction of micronucleus frequency was found. Overall, this study shows a potential of thebaine to induce genotoxic effects at high concentrations. The observation of cytotoxicity at these concentrations supports the hypothesis that genotoxicity may be caused by cytotoxic effects. Further studies will need to elucidate whether these effects are directly genotoxic or indeed result from cytotoxicity.
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Liu L, Zeng W, Yu S, Li J, Zhou J. Rapid Enabling of Gluconobacter oxydans Resistance to High D-Sorbitol Concentration and High Temperature by Microdroplet-Aided Adaptive Evolution. Front Bioeng Biotechnol 2021; 9:731247. [PMID: 34540816 PMCID: PMC8446438 DOI: 10.3389/fbioe.2021.731247] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Accepted: 08/10/2021] [Indexed: 11/26/2022] Open
Abstract
Gluconobacter oxydans is important in the conversion of D-sorbitol into l-sorbose, which is an essential intermediate for industrial-scale production of vitamin C. In a previous study, the strain G. oxydans WSH-004 could directly produce 2-keto-l-gulonic acid (2-KLG). However, its D-sorbitol tolerance was poor compared with that of other common industrial G. oxydans strains, which grew well in the presence of more than 200 g/L of D-sorbitol. This study aimed to use the microbial microdroplet culture (MMC) system for the adaptive evolution of G. oxydans WSH-004 so as to improve its tolerance to high substrate concentration and high temperature. A series of adaptively evolved strains, G. oxydans MMC1-MMC10, were obtained within 90 days. The results showed that the best strain MMC10 grew in a 300 g/L of D-sorbitol medium at 40°C. The comparative genomic analysis revealed that genetic changes related to increased tolerance were mainly in protein translation genes. Compared with the traditional adaptive evolution method, the application of microdroplet-aided adaptive evolution could improve the efficiency in terms of reducing time and simplifying the procedure for strain evolution. This research indicated that the microdroplet-aided adaptive evolution was an effective tool for improving the phenotypes with undemonstrated genotypes in a short time.
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Fons K, Jnah AJ. Arnold-Chiari Malformation: Core Concepts. Neonatal Netw 2021; 40:313-320. [PMID: 34518383 DOI: 10.1891/11-t-704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2020] [Indexed: 11/25/2022]
Abstract
Arnold-Chiari malformation (ACM), a defect that involves downward displacement of the hindbrain and herniation of the cerebellar vermis, tonsils, pons, medulla, and fourth ventricle through the foramen magnum, is the most complex of the 4 types of Chiari malformations. Unique to the other types of Chiari malformations, approximately 95 percent of infants with ACM also present with an associated myelomeningocele (MMC), the most severe form of spina bifida. Among affected infants, those with symptomatic comorbidities incur a significantly higher morbidity and mortality risk. Prompt identification and diagnosis of ACM, as well as evidence-based postnatal and postsurgical nursing and medical care, is critical. Early surgical intervention can repair an existing MMC and restore proper cerebrospinal fluid circulation, which can dramatically improve patient outcomes and quality of life, and reduce disease and health care burden.
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de Benito-Llopis L, Teus MA. Letter to the Editor: Laser Enhancements After Surface Ablation. Ophthalmol Ther 2021; 10:699-700. [PMID: 34244977 PMCID: PMC8319272 DOI: 10.1007/s40123-021-00369-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 06/24/2021] [Indexed: 11/30/2022] Open
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Dragan AM, Truta FM, Tertis M, Florea A, Schram J, Cernat A, Feier B, De Wael K, Cristea C, Oprean R. Electrochemical Fingerprints of Illicit Drugs on Graphene and Multi-Walled Carbon Nanotubes. Front Chem 2021; 9:641147. [PMID: 33796506 PMCID: PMC8007852 DOI: 10.3389/fchem.2021.641147] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 01/25/2021] [Indexed: 12/24/2022] Open
Abstract
Illicit drugs use and abuse remains an increasing challenge for worldwide authorities and, therefore, it is important to have accurate methods to detect them in seized samples, biological fluids and wastewaters. They are recently classified as the latest group of emerging pollutants as their consumption increased tremendously in recent years. Nanomaterials have gained much attention over the last decade in the development of sensors for a myriad of applications. The applicability of these nanomaterials, functionalized or not, significantly increases and it is therefore highly suitable for use in the detection of illicit drugs. We have assessed the suitability of various nanoplatforms, such as graphene (GPH), multi-walled carbon nanotubes (MWCNTs), gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs) for the electrochemical detection of illicit drugs. GPH and MWCNTs were chosen as the most suitable platforms and cocaine, 3,4-methylendioxymethamfetamine (MDMA), 3-methylmethcathinone (MMC) and α-pyrrolidinovalerophenone (PVP) were tested. Due to the hydrophobicity of the nanomaterials-based platforms which led to low signals, two strategies were followed namely, pretreatment of the electrodes in sulfuric acid by cyclic voltammetry and addition of Tween 20 to the detection buffer. Both strategies led to an increase in the oxidation signal of illicit drugs. Binary mixtures of illicit drugs with common adulterants found in street samples were also investigated. The proposed strategies allowed the sensitive detection of illicit drugs in the presence of most adulterants. The suitability of the proposed sensors for the detection of illicit drugs in spiked wastewaters was finally assessed.
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