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Primary open-angle glaucoma (POAG), the leading cause of irreversible blindness worldwide, disproportionately affects individuals of African ancestry. We conducted a genome-wide association study (GWAS) for POAG in 11,275 individuals of African ancestry (6,003 cases; 5,272 controls). We detected 46 risk loci associated with POAG at genome-wide significance. Replication and post-GWAS analyses, including functionally informed fine-mapping, multiple trait co-localization, and in silico validation, implicated two previously undescribed variants (rs1666698 mapping to DBF4P2; rs34957764 mapping to ROCK1P1) and one previously associated variant (rs11824032 mapping to ARHGEF12) as likely causal. For individuals of African ancestry, a polygenic risk score (PRS) for POAG from our mega-analysis (African ancestry individuals) outperformed a PRS from summary statistics of a much larger GWAS derived from European ancestry individuals. This study quantifies the genetic architecture similarities and differences between African and non-African ancestry populations for this blinding disease.
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Estudo de Associação Genômica Ampla , Glaucoma de Ângulo Aberto , Humanos , Predisposição Genética para Doença , Glaucoma de Ângulo Aberto/genética , População Negra/genética , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
SURF1 deficiency (OMIM # 220110) causes Leigh syndrome (LS, OMIM # 256000), a mitochondrial disorder typified by stress-induced metabolic strokes, neurodevelopmental regression and progressive multisystem dysfunction. Here, we describe two novel surf1-/- zebrafish knockout models generated by CRISPR/Cas9 technology. While gross larval morphology, fertility, and survival into adulthood appeared unaffected, surf1-/- mutants manifested adult-onset ocular anomalies and decreased swimming activity, as well as classical biochemical hallmarks of human SURF1 disease, including reduced complex IV expression and enzymatic activity and increased tissue lactate. surf1-/- larvae also demonstrated oxidative stress and stressor hypersensitivity to the complex IV inhibitor, azide, which exacerbated their complex IV deficiency, reduced supercomplex formation, and induced acute neurodegeneration typical of LS including brain death, impaired neuromuscular responses, reduced swimming activity, and absent heartrate. Remarkably, prophylactic treatment of surf1-/- larvae with either cysteamine bitartrate or N-acetylcysteine, but not other antioxidants, significantly improved animal resiliency to stressor-induced brain death, swimming and neuromuscular dysfunction, and loss of heartbeat. Mechanistic analyses demonstrated cysteamine bitartrate pretreatment did not improve complex IV deficiency, ATP deficiency, or increased tissue lactate but did reduce oxidative stress and restore glutathione balance in surf1-/- animals. Overall, two novel surf1-/- zebrafish models recapitulate the gross neurodegenerative and biochemical hallmarks of LS, including azide stressor hypersensitivity that was associated with glutathione deficiency and ameliorated by cysteamine bitartrate or N-acetylcysteine therapy.
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Deficiência de Citocromo-c Oxidase , Doença de Leigh , Animais , Adulto , Humanos , Doença de Leigh/tratamento farmacológico , Doença de Leigh/genética , Doença de Leigh/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Acetilcisteína , Cisteamina/farmacologia , Azidas/metabolismo , Morte Encefálica , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glutationa/metabolismo , LactatosRESUMO
The pathogen Phomopsis vexans causes leaf blight, fruit rot, and damping off in brinjal plants, all of which are extremely detrimental. The pathogen affects host plant photosynthetic efficiency and fruit quantity and quality. An appreciation of the pathogenicity of P. vexans is essential for the effective control of infections in the field. Consequently, the goal of this study was to characterise P. vexans in terms of their biochemistry, molecular diversity, and pathogenicity. In terms of cellulase (97.7 U), catalase (12.2 U), and ascorbate peroxidase (147.3 U) activity, isolate PV1 performed best, followed by PV5 (CL-97.0 U, CAT-11.1 U and APX-144.4 U), and PV8 (CL-88.8 U, CAT-9.8 U and APX-141.9 U). In a greenhouse pathogenicity test, isolate PV1 had the highest incidence (97%) and severity (88.6%) of disease, whereas isolate PV6 showed the lowest incidence (57.2%) and severity (70%) of disease. The biochemical enzyme activity of P. vexans corresponds well with its greenhouse pathogenicity results, and its combination can be exploited to identify pathogenic P. vexans isolates. Using RAPD and ISSR primers, molecular characterisation indicated genetic diversity but could not distinguish isolates by geographical origin or pathogenicity. The pathogen P. vexans was verified by ITS1 and ITS4 molecular analysis, and the sequences were subsequently deposited in the NCBI database. In conclusion, the enzyme activity relevant to pathogenicity (CL, CAT and APX) in conjunction with the invivo pathogenicity assay might be utilised to differentiate between pathogenic (virulent) and non-pathogenic (avirulent) P. vexans isolates and develop suitable disease management strategies.
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Solanum melongena , Frutas , Técnica de Amplificação ao Acaso de DNA Polimórfico , PhomopsisRESUMO
We explore the parameter space of the phenomenological minimal supersymmetric standard model with a light neutralino thermal dark matter (m_{χ[over Ë]_{1}^{0}}≤m_{h}/2) that is consistent with current collider and astrophysical constraints. We consider both positive and negative values of the higgsino mass parameter (µ). Our investigation shows that the recent experimental results from the LHC as well as from direct detection searches for dark matter by the LUX-ZEPLIN Collaboration rule out the Z-funnel region for the µ>0 scenario. The same results severely restrict the h-funnel region for positive µ; however, the allowed points can be probed easily with few more days of data from the LUX-ZEPLIN experiment. In the µ<0 scenario, we find that very light higgsinos in both the Z and h funnels might survive the present constraints from the electroweakino searches at the LHC, and dedicated efforts from experimental collaborations are necessary to make conclusive statements about their present status.
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Near infrared spectroscopy (NIRS) technology is frequently used to measure regional cerebral tissue oxygen saturation (rSO2). The measurement of rSO2 has diverse range of clinical application for its easy bed-side applicability, continuous monitoring, interpretation and valuable information on cerebral oxygenation. However, it also has few technical limitations; absorption by skull tissues, presence of hematomas, and other pigments such as melanin, bilirubin can affect the rSO2 measurements and thus interfere with the accuracy of monitoring. We report a case wherein low values of frontal rSO2 normalized after evacuation of bilateral fronto-temporo-parietal (FTP) chronic subdural hematoma (CSDH) in a patient with bilateral internal carotid artery (ICA) stenosis.
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Estenose das Carótidas , Hematoma Subdural Crônico , Humanos , Encéfalo , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Crânio , Oxigênio , OximetriaRESUMO
BACKGROUND: There are insufficient data about clinical outcomes in critically ill neurological patients with concomitant coronavirus disease (COVID-19). This study describes the clinical characteristics, predictors of mortality, and clinical outcomes in COVID-19-positive neurological patients managed in a dedicated COVID-19 neurointensive care unit (CNICU). METHODS: This single-center, retrospective cohort study was conducted in critically ill neurological and neurosurgical patients with concomitant COVID-19 infection admitted to the CNICU at the National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, from July to November 2020. Patients' demographic, clinical, laboratory, imaging, treatment, and outcome data were retrieved from the manual and electronic medical records. Predictors of mortality and neurological outcome were identified using logistic regression. RESULTS: During the study period, 50 COVID-19-positive neurological patients were admitted to the CNICU. Six patients were excluded from the analysis as they were managed in the CNICU for <24 hours. A poor outcome, defined as death or motor Glasgow Coma Scale <5 at hospital discharge, was observed in 34 of 44 patients (77.27%) with inhospital mortality in 26 of 44 patients (59%). Worst modified sequential organ failure assessment (MSOFA) score, lactate dehydrogenase maximum levels (LDHmax), and lymphocyte count were predictors of inhospital mortality with an odds ratio (OR) of 1.88, 1.01, and 0.87, respectively, whereas worst MSOFA and LDHmax levels were predictors for poor neurological outcome with OR of 1.99 and 1.01, respectively. CONCLUSIONS: Mortality is high in neurological patients with concomitant COVID-19 infection. Elevated inflammatory markers of COVID-19 suggest the role of systemic inflammation on clinical outcomes. Predictors of mortality and poor outcome were higher MSOFA score and elevated LDH levels. Additionally, lymphopenia was associated with mortality. HOW TO CITE THIS ARTICLE: Surve RM, Mishra RK, Malla SR, Kamath S, Chakrabarti DR, Kulanthaivelu K, et al. Clinical Characteristics and Outcomes of Critically Ill Neurological Patients with COVID-19 Infection in Neuro-intensive Care Unit: A Retrospective Study. Indian J Crit Care Med 2021;25(10):1126-1132.
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INTRODUCTION: Metastasis-associated in colon cancer 1 (MACC1), one of the prognostic markers for colonic and other tumours was noted to be overexpressed in retinoblastoma (Rb) Y79 cancer stem cells. This prompted us to evaluate its expression in primary Rb tumour and serum samples with clinicopathologic correlation. The interacting partner, c-MET was also evaluated in primary tumour tissues to explore the activation of MACC1 signaling. METHODOLOGY: This study was done following institutional review board approval from participating institutes. Semiquantitative gene expression for MACC1 was evaluated using formalin-fixed paraffin-embedded sections and unfixed tumour samples from primary Rb cases (n = 44). Immunolocalization for MACC1 was assessed in primary Rb tumours (n = 22), bone marrow aspirates with metastasis (n = 3), and c-MET expression was also assessed in Rb tumours (n = 17). Serum MACC1 levels were analysed using enzyme-linked immunosorbent assay in samples collected from Rb patients undergoing enucleation (n = 31), Rb patients with proven clinical metastasis (n = 3), and compared to appropriate controls. Clinicopathologic correlation of MACC1 expression was analysed using the medical records with specific reference to histologic risk factors (HRF) for metastasis and differentiation. RESULTS: High expression of MACC1 gene was noted in all the tumour samples (n = 44), more so in cases with versus without HRF (p < 0.0001). In cases with HRF, MACC1 and c-MET showed diffuse nuclear and cytoplasmic staining whereas it was predominantly cytoplasmic in cases without HRF. Mean immunoreactivity score of MACC1 and c-MET tissue immunolocalization revealed that cases with HRF showed significantly higher expression compared to cases without HRF (p < 0.05). Unlike the findings in colonic tumours, serum levels of MACC1 were lower in patients compared to normal controls. CONCLUSION: Overexpression of MACC1 and c-MET in retinoblastoma tissues, specifically those with risk factors for metastasis, suggests its role in proliferation and possibly in invasion. However, the current data do not support it to be a clinical prognostic marker in retinoblastoma tumours. The inverse serum expression is an intriguing finding, which warrants further studies especially in retinoblastoma.
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Retinoblastoma/genética , Transativadores/genética , Regulação para Cima , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Núcleo Celular/metabolismo , Criança , Pré-Escolar , Citoplasma/metabolismo , Feminino , Humanos , Lactente , Masculino , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Retinoblastoma/patologia , Fatores de Risco , Transativadores/sangue , Transativadores/metabolismoRESUMO
The Editor-in-Chief and the publisher have retracted this article [1] because of significant overlap with previously published articles [2-5]. Ajit Uchoi, Surendra Kumar Malik, Ravish Chaudhary, Susheel Kumar, M.R. Rohini, Digvender Pal, and Sezai Ercisli disagree with the retraction. The publisher was not able to get in contact with Rekha Chaudhury, she did not respond to any correspondence about this retraction.
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Root knot nematodes are serious threats to growth and yield of solaneous crops including tomato. In this study, a binary vector carrying Remusatia vivipara (rvl1) and Sclerotium rolfsii (srl1) lectin genes were introduced independently into Lycopersicon esculentum cv. Pusa Ruby via Agrobacterium tumefaciens for resistance against root knot nematode, Meloidogyne incognita. In total, one hundred and one rvl1 and srl1-transformed plants exhibiting kanamycin resistance were confirmed to carry transgenes as detected by polymerase chain reaction (PCR) with 4.59% transformation efficiency. Genetic analysis of T1 progeny confirmed Mendelian segregation of the introduced genes. Three events each of rvl1 and srl1 transgenic tomato were randomly selected for further confirmation by Southern and TAIL-PCR analyses. All three events of srl1 transgenics showed single copy transgene, whereas two rvl1 transgenic events showed single copy of transgene, while remaining event showed two copies of transgenes. Site of integration obtained for rvl1 and srl1 transgenic events by TAIL-PCR revealed that all the three events of rvl1 and srl1 transgenics differed for their site of integration and insertion sites did not contain any predicted gene. Moreover, expression of the rvl1 and srl1 transgenes was detected by haemagglutination assay in all three events of rvl1 and srl1, but not in non-transgenic tomato plant. Homozygous progenies of these events were grown and inoculated with M. incognita. Development and reproduction of M. incognita was severely affected in transgenic tomato plants expressing RVL1 and SRL1 exhibiting the high levels of resistance compared to non-transgenic plants. Therefore, these transgenic lines demonstrate a promising potential for variety development of tomato lines with enhanced resistance against M. incognita.
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Lectinas/metabolismo , Doenças das Plantas/imunologia , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/parasitologia , Solanum lycopersicum/metabolismo , Solanum lycopersicum/parasitologia , Tylenchoidea/fisiologia , Animais , Ascomicetos/química , Herbivoria , Lectinas/genética , Solanum lycopersicum/genética , Magnoliopsida/química , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/parasitologia , Plantas Geneticamente Modificadas/genéticaRESUMO
PURPOSE: Lacrimal gland (LG) dysfunction leading to dry eye syndrome (DES) is an important cause of ocular morbidity. One of the potential and promising long-term management therapies for restoration of LG function could be transplantation of autologous ex vivo expanded stem cells. The present study was aimed at exploring the 2D and 3D cultures of human LG, identifying inherent stem cells and evaluating their secretory potential. METHODS: Fresh human lacrimal gland (HuLG) (n = 5) from patients undergoing therapeutic exenteration was harvested after ethical approval and informed consent. The gland was enzymatically digested and the isolated cells plated in Hepato-STIM media supplemented with l-glutamine, epidermal growth factor, fibroblast growth factor, and N-2 supplement. The native HuLG and the cultured spheres (DIV14-16) were evaluated for presence of stem cells (CD117 expression, quiescence, BrdU label retention, cell cycle, colony forming efficiency) and differentiation (secretion of tear proteins). RESULTS: Under the established culture conditions, suspension 3D cultures of human "lacrispheres" could be maintained and propagated for 3-4 weeks. The spheres consist of both acinar as well as ductal cells with evidence of stem cells (0.8 ± 0.05% CD117+ cells), BrdU label retention (9.31 ± 0.41%), G0/G1 profile similar to native lacrimal cells at isolation (76.9 versus 79.9%) and colony forming units (3.1%). The lacrispheres also secreted quantifiable levels of tear proteins (lysozyme, lactoferrin, scIgA) into the conditioned media. CONCLUSION: The study provides promising, first-of-its-kind evidence for the generation of lacrispheres from fresh HuLG, with enriched population of stem cells and secretory competent differentiated cells. The dual properties of these spheres make them a highly suitable source of transplantable cells for restoring the structure and function of damaged lacrimal gland.
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Síndromes do Olho Seco/metabolismo , Proteínas do Olho/metabolismo , Aparelho Lacrimal/patologia , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Diferenciação Celular , Divisão Celular , Células Cultivadas , Meios de Cultivo Condicionados , Síndromes do Olho Seco/genética , Síndromes do Olho Seco/terapia , Citometria de Fluxo , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Aparelho Lacrimal/metabolismo , Proteínas Proto-Oncogênicas c-kit/biossíntese , Proteínas Proto-Oncogênicas c-kit/genética , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/metabolismoRESUMO
BACKGROUND: Retinoblastoma (Rb), the most common childhood intraocular malignant tumor, is reported to have cancer stem cells (CSCs) similar to other tumors. Our previous investigation in primary tumors identified the small sized cells with low CD133 (Prominin-1) and high CD44 (Hyaluronic acid receptor) expression to be putative Rb CSCs using flow cytometry (FSClo/SSClo/CD133lo/CD44hi). With this preliminary data, we have now utilized a comprehensive approach of in vitro characterization of Y79 Rb cell line following CSC enrichment using CD133 surface marker and subsequent validation to confirm the functional properties of CSCs. METHODS: The cultured Rb Y79 cells were evaluated for surface markers by flow cytometry and CD133 sorted cells (CD133lo/CD133hi) were compared for CSC characteristics by size/percentage, cell cycle assay, colony formation assay, differentiation, Matrigel transwell invasion assay, cytotoxicity assay, gene expression using microarray and validation by semi-quantitative PCR. RESULTS: Rb Y79 cell line shared the profile (CD133, CD90, CXCR4 and ABCB1) of primary tumors except for CD44 expression. The CD133lo cells (16.1 ± 0.2%) were FSClo/SSClo, predominantly within the G0/G1 phase, formed larger and higher number of colonies with ability to differentiate to CD133hi cells, exhibited increased invasive potential in a matrigel transwell assay (p < 0.05) and were resistant to Carboplatin treatment (p < 0.001) as compared to CD133hi cells. The CD133lo cells showed higher expression of several embryonic stem cell genes (HOXB2, HOXA9, SALL1, NANOG, OCT4, LEFTY), stem cells/progenitor genes (MSI2, BMI1, PROX1, ABCB1, ABCB5, ABCG2), and metastasis related gene- MACC1, when compared to the CD133hi cells. CONCLUSIONS: This study validates the observation from our earlier primary tumor study that CSC properties in Rb Y79 cell line are endowed within the CD133lo population, evident by their characteristics- i.e. small sized, dormant in nature, increased colony forming ability, differentiation to CD133hi cells, higher invasiveness potential, drug resistance and primitive gene expression pattern. These findings provide a proof of concept for methodological characterization of the retinoblastoma CSCs with future implications for improved diagnostic and treatment strategies.
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Antígeno AC133/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fenótipo , Retinoblastoma/metabolismo , Antígeno AC133/genética , Biomarcadores , Ciclo Celular , Linhagem Celular Tumoral , Citometria de Fluxo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imunofenotipagem , Células-Tronco Neoplásicas/patologia , Retinoblastoma/genética , Retinoblastoma/patologia , Ensaio Tumoral de Célula-TroncoRESUMO
Phylogenetic relationships of Indian Citron (Citrus medica L.) with other important Citrus species have been inferred through sequence analyses of rbcL and matK gene region of chloroplast DNA. The study was based on 23 accessions of Citrus genotypes representing 15 taxa of Indian Citrus, collected from wild, semi-wild, and domesticated stocks. The phylogeny was inferred using the maximum parsimony (MP) and neighbor-joining (NJ) methods. Both MP and NJ trees separated all the 23 accessions of Citrus into five distinct clusters. The chloroplast DNA (cpDNA) analysis based on rbcL and matK sequence data carried out in Indian taxa of Citrus was useful in differentiating all the true species and species/varieties of probable hybrid origin in distinct clusters or groups. Sequence analysis based on rbcL and matK gene provided unambiguous identification and disposition of true species like C. maxima, C. medica, C. reticulata, and related hybrids/cultivars. The separation of C. maxima, C. medica, and C. reticulata in distinct clusters or sub-clusters supports their distinctiveness as the basic species of edible Citrus. However, the cpDNA sequence analysis of rbcL and matK gene could not find any clear cut differentiation between subgenera Citrus and Papeda as proposed in Swingle's system of classification.
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Cloroplastos/genética , Citrus/classificação , Citrus/genética , Análise de Sequência de DNA/métodos , DNA de Cloroplastos/genética , Evolução Molecular , Variação Genética , Genótipo , FilogeniaRESUMO
Alzheimer's disease (AD) is an illness that affects the nervous system, leading to a loss in cognitive and logical abilities. Gene regulatory expressions, which are the complex language exhibited by DNA, serve several functionalities, including the physical and biological life cycle processes in the human body. The gene expression sequence affects the pathology experienced by an individual, its longevity, and potential for a cure. The transcription factors, from DNA to RNA conversion, and the binding process determine the gene expression, which varies for every human organ and disease. This study proposes Deep convolutional neural network model that reads the gene regulatory expression sequence through various convolutional layers encoded to detect positive spikes in transcription factors. This results in the prediction of disease conversion probability from mild cognitive impairment to AD which is the key-requisite for affected geriatric cohorts.
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Lesions at the cerebellopontine angle (CP angle) are associated with various brain-heart interactions, which can include those from stimulation of the fifth cranial nerve along the scalp incision in a retrosigmoid suboccipital surgical approach. A 27-year-old male patient with recently diagnosed hypertension (on calcium channel blocker) underwent left CP angle lesion decompression. Transient episodes of bradycardia, hypotension, and bradypnea were observed from the skin incision onward, exacerbated during tumor manipulation. Most episodes subsided with cessation of the surgical stimulus while some required intervention. Postoperatively, blood pressure decreased below the pre-operative levels. Thus, trigeminocardiac reflex can occur as early as the skin incision even in a retrosigmoid approach due to stimulation of the mandibular division, when specific risk factors exist. Such episodes may serve as early warning signs for subsequent intraoperative occurrences. Brainstem compression can be a possible etiology of hypertension in young patients. It underscores the importance of considering brain-heart interactions in surgical interventions involving the CP angle.
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BACKGROUND: Guillain-Barré syndrome (GBS) is an autoimmune disorder characterized by demyelination of peripheral nerves. GBS-associated posterior reversible encephalopathy syndrome (PRES) is a rare and potentially life-threatening complication in the pediatric population. We aimed to report and analyze the clinical features, management, and outcomes of three cases of GBS-associated PRES in our setting in the light of the existing literature. METHODS: Medical records of 75 pediatric patients with GBS were reviewed for autonomic changes and GBS-associated PRES. Thirty-one developed dysautonomia while three were identified to have PRES. Clinical, radiological, laboratory, and treatment data were collected and analyzed. RESULTS: All three patients were male and presented with symptoms of acute flaccid paralysis and respiratory distress requiring mechanical ventilation. All three patients experienced various complications, including hypertension, seizures, and hyponatremia, and were subsequently diagnosed with PRES. Multimodal intensive care resulted in patient improvement and discharge in an ambulatory state after an average of 104 days of care. CONCLUSIONS: GBS-associated PRES is a rare and potentially life-threatening complication that can occur in pediatric patients with GBS. Our findings suggest that early recognition, prompt intervention, and multimodal intensive care can improve patient outcomes. Further studies are needed to determine optimal treatment strategies for GBS-associated PRES.
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Síndrome de Guillain-Barré , Síndrome da Leucoencefalopatia Posterior , Humanos , Síndrome de Guillain-Barré/terapia , Síndrome de Guillain-Barré/complicações , Síndrome de Guillain-Barré/fisiopatologia , Masculino , Síndrome da Leucoencefalopatia Posterior/etiologia , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Síndrome da Leucoencefalopatia Posterior/terapia , Síndrome da Leucoencefalopatia Posterior/fisiopatologia , Criança , Adolescente , Pré-EscolarRESUMO
Guillain-Barré syndrome is the most common cause of acute flaccid paralysis in children, but several diseases mimic GBS. We aimed to identify and report the clinical pointers and battery of tests required to differentiate Guillain-Barré syndrome from its observed mimics in the pediatric population admitted to our neuro-critical care unit. We conducted a retrospective record analysis of all pediatric patients admitted over ten years from 2008-2018, whose initial presentation was compatible with a clinical diagnosis of GBS. Eighty-three patients were at first treated as GBS, of which seven (8.4%) were found to have an alternate diagnosis-three cases of paralytic rabies, one case each of acute disseminated encephalomyelitis, cervical myeloradiculopathy, neuromyelitis optica, and a case of community-acquired Staphylococcus aureus pneumonia associated sepsis. Neurophysiological and neuro-virological testing, central nervous system imaging, and sepsis screening helped to confirm the alternate diagnosis. Our case series provides knowledge of subtle clinical differences along with the mindful use of diagnostic testing to facilitate the accurate diagnosis of GBS mimics.
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Síndrome de Guillain-Barré , Centros de Atenção Terciária , Humanos , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/fisiopatologia , Criança , Estudos Retrospectivos , Feminino , Masculino , Diagnóstico Diferencial , Pré-Escolar , Adolescente , Unidades de Terapia Intensiva , Lactente , Encefalomielite Aguda Disseminada/diagnósticoRESUMO
We report the extraction of keratin nanofibers from the medulla of a parent yarn after denaturing the cuticle and cortex microstructures of a merino wool yarn. Controlled alkaline hydrolysis, followed by high-speed blending in acetic acid, allowed for the extraction of keratin protein nanofibers with an average diameter of 25 nm and a length of less than 3 µm. SEM and AFM analyses showed the removal of cuticle cells from the yarn. FT-IR and DSC analyses confirmed the hydrolysis and denaturation of the sheet protein matrix of cuticle cells. XPS analysis provided strong evidence for the gradual removal of the epicuticle, cuticle cells, and cortex of the hierarchical wool structure with an increase in alkaline hydrolysis conditions. It was confirmed that the merino wool yarn subjected to hydrolysis under alkaline conditions exposed its internal fibrillar surface. In an acetic acid medium, these fibrillar surfaces obtained a surface charge, which further supported the defibrillation of the structure into its individual nanofibrils during high-speed blending. The extracted nanostructures constitute mainly α-helical proteins. The morphology of the nanofibers is composed of a uniform circular cross-section based on the images obtained using AFM, TEM, and SEM. The extracted nanofibers were successfully fabricated into transparent sheets that can be used in several applications.
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The emergence of resistance in detrimental pathogenic bacteria towards well-recognized antibiotics has greatly impacted global medicine, consequently exploring potent antibacterial compounds is becoming a potential area of research. Although photocatalytic metal oxides have been extensively explored in this regard, their applicability is diminished due to the requirement of photon energy. Therefore, in our study, we explored the light-independent antibacterial effect of two unexplored titanium species, known as metatitanic acid (MTA) and potassium titanate, against Staphylococcus aureus, Escherichia coli, and Pseudomonas spp. using the disk diffusion method in Luria-Bertani agar medium, where the well-known antibiotic, gentamicin, was used as the positive control. These two titanium compounds were readily synthesized through a novel process which was originally developed for the extraction of TiO2 from ilmenite. The synthesized MTA was characterized using FT-IR, Raman spectroscopy, XRD, TGA, UV-visible spectroscopy, and SEM. According to our findings, both MTA and potassium titanate exhibited superior light-independent antibacterial properties, where for some concentrations, the effect was even greater than gentamicin. However, nano-TiO2 totally failed as an antibacterial compound against the tested three strains under dark conditions.