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1.
Nature ; 606(7916): 960-967, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35705808

RESUMO

Among the caspases that cause regulated cell death, a unique function for caspase-7 has remained elusive. Caspase-3 performs apoptosis, whereas caspase-7 is typically considered an inefficient back-up. Caspase-1 activates gasdermin D pores to lyse the cell; however, caspase-1 also activates caspase-7 for unknown reasons1. Caspases can also trigger cell-type-specific death responses; for example, caspase-1 causes the extrusion of intestinal epithelial cell (IECs) in response to infection with Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium)2,3. Here we show in both organoids and mice that caspase-7-deficient IECs do not complete extrusion. Mechanistically, caspase-7 counteracts gasdermin D pores and preserves cell integrity by cleaving and activating acid sphingomyelinase (ASM), which thereby generates copious amounts of ceramide to enable enhanced membrane repair. This provides time to complete the process of IEC extrusion. In parallel, we also show that caspase-7 and ASM cleavage are required to clear Chromobacterium violaceum and Listeria monocytogenes after perforin-pore-mediated attack by natural killer cells or cytotoxic T lymphocytes, which normally causes apoptosis in infected hepatocytes. Therefore, caspase-7 is not a conventional executioner but instead is a death facilitator that delays pore-driven lysis so that more-specialized processes, such as extrusion or apoptosis, can be completed before cell death. Cells must put their affairs in order before they die.


Assuntos
Caspase 7 , Perforina , Proteínas de Ligação a Fosfato , Proteínas Citotóxicas Formadoras de Poros , Esfingomielina Fosfodiesterase , Animais , Apoptose , Caspase 7/metabolismo , Chromobacterium/imunologia , Células Epiteliais/citologia , Intestinos/citologia , Células Matadoras Naturais/imunologia , Listeria monocytogenes/imunologia , Camundongos , Organoides , Perforina/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Linfócitos T Citotóxicos/imunologia
2.
Proc Natl Acad Sci U S A ; 119(28): e2204511119, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35867748

RESUMO

Despite excellent vaccines, resurgent outbreaks of hepatitis A have caused thousands of hospitalizations and hundreds of deaths within the United States in recent years. There is no effective antiviral therapy for hepatitis A, and many aspects of the hepatitis A virus (HAV) replication cycle remain to be elucidated. Replication requires the zinc finger protein ZCCHC14 and noncanonical TENT4 poly(A) polymerases with which it associates, but the underlying mechanism is unknown. Here, we show that ZCCHC14 and TENT4A/B are required for viral RNA synthesis following translation of the viral genome in infected cells. Cross-linking immunoprecipitation sequencing (CLIP-seq) experiments revealed that ZCCHC14 binds a small stem-loop in the HAV 5' untranslated RNA possessing a Smaug recognition-like pentaloop to which it recruits TENT4. TENT4 polymerases lengthen and stabilize the 3' poly(A) tails of some cellular and viral mRNAs, but the chemical inhibition of TENT4A/B with the dihydroquinolizinone RG7834 had no impact on the length of the HAV 3' poly(A) tail, stability of HAV RNA, or cap-independent translation of the viral genome. By contrast, RG7834 inhibited the incorporation of 5-ethynyl uridine into nascent HAV RNA, indicating that TENT4A/B function in viral RNA synthesis. Consistent with potent in vitro antiviral activity against HAV (IC50 6.11 nM), orally administered RG7834 completely blocked HAV infection in Ifnar1-/- mice, and sharply reduced serum alanine aminotransferase activities, hepatocyte apoptosis, and intrahepatic inflammatory cell infiltrates in mice with acute hepatitis A. These results reveal requirements for ZCCHC14-TENT4A/B in hepatovirus RNA synthesis, and suggest that TENT4A/B inhibitors may be useful for preventing or treating hepatitis A in humans.


Assuntos
Proteínas Cromossômicas não Histona , DNA Polimerase Dirigida por DNA , Vírus da Hepatite A , Hepatite A , Proteínas Intrinsicamente Desordenadas , RNA Nucleotidiltransferases , RNA Viral , Replicação Viral , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Proteínas Cromossômicas não Histona/metabolismo , DNA Polimerase Dirigida por DNA/metabolismo , Hepatite A/tratamento farmacológico , Hepatite A/metabolismo , Hepatite A/virologia , Vírus da Hepatite A/efeitos dos fármacos , Vírus da Hepatite A/genética , Vírus da Hepatite A/fisiologia , Humanos , Proteínas Intrinsicamente Desordenadas/metabolismo , Camundongos , Camundongos Mutantes , RNA Nucleotidiltransferases/metabolismo , RNA Viral/biossíntese , RNA Viral/genética , Receptor de Interferon alfa e beta/genética , Replicação Viral/efeitos dos fármacos
3.
Nucleic Acids Res ; 48(D1): D835-D844, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31777943

RESUMO

ClinVar is a freely available, public archive of human genetic variants and interpretations of their relationships to diseases and other conditions, maintained at the National Institutes of Health (NIH). Submitted interpretations of variants are aggregated and made available on the ClinVar website (https://www.ncbi.nlm.nih.gov/clinvar/), and as downloadable files via FTP and through programmatic tools such as NCBI's E-utilities. The default view on the ClinVar website, the Variation page, was recently redesigned. The new layout includes several new sections that make it easier to find submitted data as well as summary data such as all diseases and citations reported for the variant. The new design also better represents more complex data such as haplotypes and genotypes, as well as variants that are in ClinVar as part of a haplotype or genotype but have no interpretation for the single variant. ClinVar's variant-centric XML had its production release in April 2019. The ClinVar website and E-utilities both have been updated to support the VCV (variation in ClinVar) accession numbers found in the variant-centric XML file. ClinVar's search engine has been fine-tuned for improved retrieval of search results.


Assuntos
Bases de Dados Genéticas , Doença/genética , Variação Genética/genética , Genoma Humano , Genômica , Haplótipos , Humanos , Internet , National Library of Medicine (U.S.) , Ferramenta de Busca , Estados Unidos
4.
J Med Internet Res ; 24(3): e27210, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35319481

RESUMO

BACKGROUND: Information in pathology reports is critical for cancer care. Natural language processing (NLP) systems used to extract information from pathology reports are often narrow in scope or require extensive tuning. Consequently, there is growing interest in automated deep learning approaches. A powerful new NLP algorithm, bidirectional encoder representations from transformers (BERT), was published in late 2018. BERT set new performance standards on tasks as diverse as question answering, named entity recognition, speech recognition, and more. OBJECTIVE: The aim of this study is to develop a BERT-based system to automatically extract detailed tumor site and histology information from free-text oncological pathology reports. METHODS: We pursued three specific aims: extract accurate tumor site and histology descriptions from free-text pathology reports, accommodate the diverse terminology used to indicate the same pathology, and provide accurate standardized tumor site and histology codes for use by downstream applications. We first trained a base language model to comprehend the technical language in pathology reports. This involved unsupervised learning on a training corpus of 275,605 electronic pathology reports from 164,531 unique patients that included 121 million words. Next, we trained a question-and-answer (Q&A) model that connects a Q&A layer to the base pathology language model to answer pathology questions. Our Q&A system was designed to search for the answers to two predefined questions in each pathology report: What organ contains the tumor? and What is the kind of tumor or carcinoma? This involved supervised training on 8197 pathology reports, each with ground truth answers to these 2 questions determined by certified tumor registrars. The data set included 214 tumor sites and 193 histologies. The tumor site and histology phrases extracted by the Q&A model were used to predict International Classification of Diseases for Oncology, Third Edition (ICD-O-3), site and histology codes. This involved fine-tuning two additional BERT models: one to predict site codes and another to predict histology codes. Our final system includes a network of 3 BERT-based models. We call this CancerBERT network (caBERTnet). We evaluated caBERTnet using a sequestered test data set of 2050 pathology reports with ground truth answers determined by certified tumor registrars. RESULTS: caBERTnet's accuracies for predicting group-level site and histology codes were 93.53% (1895/2026) and 97.6% (1993/2042), respectively. The top 5 accuracies for predicting fine-grained ICD-O-3 site and histology codes with 5 or more samples each in the training data set were 92.95% (1794/1930) and 96.01% (1853/1930), respectively. CONCLUSIONS: We have developed an NLP system that outperforms existing algorithms at predicting ICD-O-3 codes across an extensive range of tumor sites and histologies. Our new system could help reduce treatment delays, increase enrollment in clinical trials of new therapies, and improve patient outcomes.


Assuntos
Processamento de Linguagem Natural , Neoplasias , Algoritmos , Humanos , Idioma , Oncologia
5.
J Hepatol ; 75(6): 1323-1334, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34331968

RESUMO

BACKGROUND & AIMS: Hepatitis A virus (HAV) is a common cause of enterically transmitted viral hepatitis. In non-immune individuals, infection results in typically transient but occasionally fulminant and fatal inflammatory liver injury. Virus-specific T cell frequencies peak when liver damage is at its zenith, leading to the prevalent notion that T cells exacerbate liver disease, as suspected for other hepatotropic virus infections. However, the overall contribution of T cells to the control of HAV and the pathogenesis of hepatitis A is unclear and has been impeded by a historic lack of small animal models. METHODS: Ifnar1-/- mice are highly permissive for HAV and develop pathogenesis that recapitulates many features of hepatitis A. Using this model, we identified HAV-specific CD8+ and CD4+ T cells by epitope mapping, and then used tetramers and functional assays to quantify T cells in the liver at multiple times after infection. We assessed the relationships between HAV-specific T cell frequency, viral RNA amounts, and liver pathogenesis. RESULTS: A large population of virus-specific T cells accumulated within the livers of Ifnar1-/- mice during the first 1-2 weeks of infection and persisted over time. HAV replication was enhanced and liver disease exacerbated when mice were depleted of T cells. Conversely, immunization with a peptide vaccine increased virus-specific CD8+ T cell frequencies in the liver, reduced viral RNA abundance, and lessened liver injury. CONCLUSION: These data show that T cells protect against HAV-mediated liver injury and can be targeted to improve liver health. LAY SUMMARY: Hepatitis A virus is a leading cause of acute viral hepatitis worldwide. T cells were thought to contribute to liver injury during acute infection. We now show that virus-specific T cells protect against infection and limit liver injury.


Assuntos
Hepatite A/prevenção & controle , Hepatopatias/prevenção & controle , Linfócitos T/metabolismo , Análise de Variância , Animais , Modelos Animais de Doenças , Hepatite A/tratamento farmacológico , Hepatite A/epidemiologia , Vírus da Hepatite A/efeitos dos fármacos , Vírus da Hepatite A/patogenicidade , Hepatopatias/tratamento farmacológico , Hepatopatias/epidemiologia , Camundongos , North Carolina , Estatísticas não Paramétricas , Linfócitos T/fisiologia
6.
Ecol Appl ; 31(2): e02249, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33140872

RESUMO

Community occupancy models estimate species-specific parameters while sharing information across species by treating parameters as sampled from a common distribution. When communities consist of discrete groups, shrinkage of estimates toward the community mean can mask differences among groups. Infinite-mixture models using a Dirichlet process (DP) distribution, in which the number of latent groups is estimated from the data, have been proposed as a solution. In addition to community structure, these models estimate species similarity, which allows testing hypotheses about whether traits drive species response to environmental conditions. We develop a community occupancy model (COM) using a DP distribution to model species-level parameters. Because clustering algorithms are sensitive to dimensionality and distinctiveness of clusters, we conducted a simulation study to explore performance of the DP-COM with different dimensions (i.e., different numbers of model parameters with species-level DP random effects) and under varying cluster differences. Because the DP-COM is computationally expensive, we compared its estimates to a COM with a normal random species effect. We further applied the DP-COM model to a bird data set from Uganda. Estimates of the number of clusters and species cluster identity improved with increasing difference among clusters and increasing dimensions of the DP; but the number of clusters was always overestimated. Estimates of number of sites occupied and species and community-level covariate coefficients on occupancy probability were generally unbiased with (near-) nominal 95% Bayesian Credible Interval coverage. Accuracy of estimates from the normal and the DP-COM was similar. The DP-COM clustered 166 bird species into 27 clusters regarding their affiliation with open or woodland habitat and distance to oil wells. Estimates of covariate coefficients were similar between a normal and the DP-COM. Except sunbirds, species within a family were not more similar in their response to these covariates than the overall community. Given that estimates were consistent between the normal and the DP-COM, and considering the computational burden for the DP models, we recommend using the DP-COM only when the analysis focuses on community structure and species similarity, as these quantities can only be obtained under the DP-COM.


Assuntos
Algoritmos , Ecossistema , Teorema de Bayes , Simulação por Computador
7.
Surg Technol Int ; 37: 280-289, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33217759

RESUMO

INTRODUCTION: Opioids are frequently prescribed in the postoperative management of total knee arthroplasty (TKA) with multiple factors influencing postoperative opioid use. Robotic-arm-assisted TKA (raTKA) was developed with the goal of improving alignment and outcomes while decreasing soft tissue injury. The purpose of this study was to compare postoperative opioid consumption in raTKA and conventional manual TKA (mTKA) cohorts. MATERIALS AND METHODS: A consecutive series of unilateral primary TKAs performed 1/1/16 to 12/31/17 were included. Patients with major procedures requiring opioids occurring within one year of TKA were excluded. A single-surgeon raTKA cohort of 127 patients (Group 1) was compared to a same-surgeon cohort of 119 mTKAs (Group 2) using the same cemented implant design and a two-surgeon cohort of 410 mTKA (Group 3). Groups were subdivided into opioid naïve (ON) and opioid exposed (OE). Length of hospitalization and postoperative opioid utilization up to one year were compared between groups and collectively without separating raTKA and mTKA. Statistical analysis included Chi-square, Student's t-test, and Wilcoxon rank sum tests. RESULTS: For both ON and OE patients, Group 1 demonstrated reduced inpatient mean daily oral morphine milligram equivalent (MME) compared to Group 3 (ON p=0.007; OE p=0.034), a shorter hospitalization compared to Group 2 (ON p=0.02; OE p=0.012), and fewer opioids prescribed at discharge compared to Group 2 (ON p=0.005; OE p=0.081) and Group 3 (ON p<0.001; OE p=0.036). No differences in opioid prescriptions were seen at three months or after. Regardless of surgical technique OE patients had higher inpatient opioid utilization (p<0.001) as well as cumulative outpatient prescription quantity (MME 1050 ON, 2660 OE) and duration (ON 0.5%; OE 28.3%) at one year (p<0.001). CONCLUSION: Less opioids were prescribed at discharge and used during hospitalization in raTKA compared to mTKA though no differences in opioid use were seen at further time points. Preoperative opioid use remains a dominant factor in postoperative opioid utilization regardless of TKA surgical technique.


Assuntos
Artroplastia do Joelho , Transtornos Relacionados ao Uso de Opioides , Procedimentos Cirúrgicos Robóticos , Analgésicos Opioides/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Humanos , Articulação do Joelho/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/epidemiologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos
8.
Molecules ; 25(11)2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486282

RESUMO

A series of model polyelectrolyte complex micelles (PCMs) was prepared to investigate the consequences of neutral and zwitterionic chemistries and distinct charged cores on the size and stability of nanocarriers. Using aqueous reversible addition-fragmentation chain transfer (RAFT) polymerization, we synthesized a well-defined diblock polyelectrolyte system, poly(2-methacryloyloxyethyl phosphorylcholine methacrylate)-block-poly((vinylbenzyl) trimethylammonium) (PMPC-PVBTMA), at various neutral and charged block lengths to compare directly against PCM structure-property relationships centered on poly(ethylene glycol)-block-poly((vinylbenzyl) trimethylammonium) (PEG-PVBTMA) and poly(ethylene glycol)-block-poly(l-lysine) (PEG-PLK). After complexation with a common polyanion, poly(sodium acrylate), the resulting PCMs were characterized by dynamic light scattering (DLS) and small angle X-ray scattering (SAXS). We observed uniform assemblies of spherical micelles with a diameter ~1.5-2× larger when PMPC-PVBTMA was used compared to PEG-PLK and PEG-PVBTMA via SAXS and DLS. In addition, PEG-PLK PCMs proved most resistant to dissolution by both monovalent and divalent salt, followed by PEG-PVBTMA then PMPC-PVBTMA. All micelle systems were serum stable in 100% fetal bovine serum over the course of 8 h by time-resolved DLS, demonstrating minimal interactions with serum proteins and potential as in vivo drug delivery vehicles. This thorough study of the synthesis, assembly, and characterization of zwitterionic polymers in PCMs advances the design space for charge-driven micelle assemblies.


Assuntos
Polieletrólitos/química , Polietilenoglicóis/química , Polímeros/química , Difusão Dinâmica da Luz , Micelas , Espalhamento a Baixo Ângulo , Difração de Raios X
9.
J Pediatr Orthop ; 38(5): e271-e277, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29635261

RESUMO

BACKGROUND: Residual equinus deformity is present in up to 20% of clubfeet treated by the Ponseti method. These patients may require surgical release to restore dorsiflexion. Despite complete posterior release; persistent intraoperative equinus may be present and suggest concurrent joint incongruity. The purpose of this study was to characterize differences in ankle morphology in toddlers with residual equinus following the Ponseti method. METHODS: Preoperative magnetic resonance imaging (MRI) data from 10 patients who underwent reconstruction (17 feet; 7 bilateral, 3 unilateral clubfeet) for persistent equinus were compared with 16 age-matched controls. Through reverse engineering software, MRI data were used to generate 3-dimensional (3D) models. Four talus-based measures were performed on both MRI data and 3D models-neck depth, neck angle, width, and length. Models were also used to calculate talus volume and arc of curvature (plafond and talar dome). Standard statistical analyses were performed. RESULTS: Talus volumes, width, and length were less in clubfeet then in control feet. Although some measures were significant there was no mismatch with the ankle mortise dimensions or arc curvature that could account for any decrease in dorsiflexion. We found that from MRI measures the clubfoot neck depth was 2.3 versus 3.6 mm in controls (P<0.001) and from 3D modeling the clubfoot neck depth was 2.3 and 3.5 mm in controls (P=0.003). With 3D modeling talus clubfoot neck angle was 153.7 versus 140.4 degrees in controls (P=0.01). The clubfoot neck angle obtained from MRI measures were also different yet not significant [126.6 in clubfeet versus 122.5 degrees in controls (P=0.12)]. CONCLUSIONS: In comparison to age-matched feet; we have noted a decrease in talar neck depth and an obtuse talar neck angle in clubfeet treated in the manner of Ponseti. This may result in anterior ankle impingement and be the cause of residual equinus despite posterior release. In these procedures, the surgeon should recognize this possibility when the amount of dorsiflexion is less than expected. LEVEL OF EVIDENCE: Level III-case control study.


Assuntos
Moldes Cirúrgicos , Pé Torto Equinovaro , Pé Equino , Procedimentos Ortopédicos , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Estudos de Casos e Controles , Pré-Escolar , Pé Torto Equinovaro/diagnóstico , Pé Torto Equinovaro/cirurgia , Pé Equino/diagnóstico , Pé Equino/etiologia , Pé Equino/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Procedimentos Ortopédicos/efeitos adversos , Procedimentos Ortopédicos/instrumentação , Procedimentos Ortopédicos/métodos , Resultado do Tratamento
10.
Zoo Biol ; 33(6): 577-85, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25231013

RESUMO

The pathogen Batrachochytrium dendrobatidis (Bd) can be challenging to detect at endangered amphibian reintroduction sites. Pre-release Bd detection can be confounded by imperfect animal sampling and the absence of animals. In Study 1, we used historical Bd-positive sites, to concurrently evaluate water filtrates and mouth bar (tadpoles) or skin swab (caudates) samples for Bd using molecular beacon realtime PCR. In Study 2, during a natural outbreak, we used PCR to detect Bd from zoospore-attracting keratin baits (three avian, three snake species). In Study 1, no captured animals (n=116) exhibited clinical signs, although 10.6% were positive, representing three of seven species sampled. In contrast, 5.4% of water filters (n=56) were Bd-positive. In Study 2, after short incubation times, a single duck down feather tested Bd-positive. In conclusion, Bd was detected in asymptomatic amphibians and water filtrate at two sites, and from water only, at two other sites. With continued refinement, semi-quantitative Bd water filtrate screening could better define zoospore-specific disease risk, allowing better characterization of the free-living phase of the organism's life cycle. Finally, these results suggest wild aquatic birds (e.g., waterfowl) should be systematically explored as a means of Bd spread. Since large numbers of aquatic birds migrate, even low Bd transfer rates could be a significant means for disease dissemination.


Assuntos
Anuros/microbiologia , Quitridiomicetos/isolamento & purificação , Água Doce/microbiologia , Animais , Quitridiomicetos/patogenicidade , Primers do DNA/genética , Patos/microbiologia , Plumas/microbiologia , Larva/microbiologia , North Carolina , Reação em Cadeia da Polimerase em Tempo Real , Serpentes/microbiologia , Virginia
11.
Drug Saf ; 46(12): 1335-1352, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37804398

RESUMO

INTRODUCTION: Individual case reports are the main asset in pharmacovigilance signal management. Signal validation is the first stage after signal detection and aims to determine if there is sufficient evidence to justify further assessment. Throughout signal management, a prioritization of signals is continually made. Routinely collected health data can provide relevant contextual information but are primarily used at a later stage in pharmacoepidemiological studies to assess communicated signals. OBJECTIVE: The aim of this study was to examine the feasibility and utility of analysing routine health data from a multinational distributed network to support signal validation and prioritization and to reflect on key user requirements for these analyses to become an integral part of this process. METHODS: Statistical signal detection was performed in VigiBase, the WHO global database of individual case safety reports, targeting generic manufacturer drugs and 16 prespecified adverse events. During a 5-day study-a-thon, signal validation and prioritization were performed using information from VigiBase, regulatory documents and the scientific literature alongside descriptive analyses of routine health data from 10 partners of the European Health Data and Evidence Network (EHDEN). Databases included in the study were from the UK, Spain, Norway, the Netherlands and Serbia, capturing records from primary care and/or hospitals. RESULTS: Ninety-five statistical signals were subjected to signal validation, of which eight were considered for descriptive analyses in the routine health data. Design, execution and interpretation of results from these analyses took up to a few hours for each signal (of which 15-60 minutes were for execution) and informed decisions for five out of eight signals. The impact of insights from the routine health data varied and included possible alternative explanations, potential public health and clinical impact and feasibility of follow-up pharmacoepidemiological studies. Three signals were selected for signal assessment, two of these decisions were supported by insights from the routine health data. Standardization of analytical code, availability of adverse event phenotypes including bridges between different source vocabularies, and governance around the access and use of routine health data were identified as important aspects for future development. CONCLUSIONS: Analyses of routine health data from a distributed network to support signal validation and prioritization are feasible in the given time limits and can inform decision making. The cost-benefit of integrating these analyses at this stage of signal management requires further research.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Farmacovigilância , Humanos , Sistemas de Notificação de Reações Adversas a Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Bases de Dados Factuais , Países Baixos
12.
BMJ Case Rep ; 15(1)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35058286

RESUMO

Concurrent epistaxis, embolic stroke and a ruptured internal carotid artery are rare but life-threatening delayed complications of cured nasopharyngeal squamous cell carcinoma. A timely diagnosis and effective management can be problematic. We report a case that highlights the unique diagnostic features of this presentation and contemporary endovascular treatment options available.


Assuntos
Aneurisma , AVC Embólico , Neoplasias Nasofaríngeas , Artéria Carótida Interna/diagnóstico por imagem , Epistaxe/etiologia , Humanos
13.
Front Neuroimaging ; 1: 832512, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37555156

RESUMO

Automatic brain tumor segmentation is particularly challenging on magnetic resonance imaging (MRI) with marked pathologies, such as brain tumors, which usually cause large displacement, abnormal appearance, and deformation of brain tissue. Despite an abundance of previous literature on learning-based methodologies for MRI segmentation, few works have focused on tackling MRI skull stripping of brain tumor patient data. This gap in literature can be associated with the lack of publicly available data (due to concerns about patient identification) and the labor-intensive nature of generating ground truth labels for model training. In this retrospective study, we assessed the performance of Dense-Vnet in skull stripping brain tumor patient MRI trained on our large multi-institutional brain tumor patient dataset. Our data included pretreatment MRI of 668 patients from our in-house institutional review board-approved multi-institutional brain tumor repository. Because of the absence of ground truth, we used imperfect automatically generated training labels using SPM12 software. We trained the network using common MRI sequences in oncology: T1-weighted with gadolinium contrast, T2-weighted fluid-attenuated inversion recovery, or both. We measured model performance against 30 independent brain tumor test cases with available manual brain masks. All images were harmonized for voxel spacing and volumetric dimensions before model training. Model training was performed using the modularly structured deep learning platform NiftyNet that is tailored toward simplifying medical image analysis. Our proposed approach showed the success of a weakly supervised deep learning approach in MRI brain extraction even in the presence of pathology. Our best model achieved an average Dice score, sensitivity, and specificity of, respectively, 94.5, 96.4, and 98.5% on the multi-institutional independent brain tumor test set. To further contextualize our results within existing literature on healthy brain segmentation, we tested the model against healthy subjects from the benchmark LBPA40 dataset. For this dataset, the model achieved an average Dice score, sensitivity, and specificity of 96.2, 96.6, and 99.2%, which are, although comparable to other publications, slightly lower than the performance of models trained on healthy patients. We associate this drop in performance with the use of brain tumor data for model training and its influence on brain appearance.

14.
Ther Adv Drug Saf ; 13: 20420986221118972, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36052399

RESUMO

Pharmacovigilance (PV) came suddenly into the spotlight when several new vaccines, developed as a response to the COVID-19 pandemic, received emergency authorisation and were rolled out on a large scale in late 2020. The vaccines underwent stringent clinical trials and evaluation from regulatory authorities, but with the use of novel technology and an anticipated rapid and vast deployment of the vaccines, the importance of a well-functioning international post marketing safety surveillance system was stressed. International PV stakeholders were faced with several challenges due to the extent of the global vaccination campaign. The unprecedented volume of reports of suspected adverse events following immunization has led to the development and use of new tools. Furthermore, the collaboration between various PV stakeholders was encouraged and strengthened. PV rose to the challenges posed by the currently ongoing global COVID-19 vaccination campaign and successful adaptations were made in a short period of time. However, the pandemic has not ended yet, the vaccination campaign is far from being completed, and further challenges are anticipated. Advances made during the pandemic will be important to strengthen PV in future and ensure to advance medicines' safety together. Plain Language Summary: Global safety monitoring of the COVID-19 vaccines: challenges, preparations, and outlooks Pharmacovigilance (PV) is the umbrella term for all sciences and activities relating to the detection, assessment, understanding, and prevention of adverse effects relating to medicines or vaccines. PV came into the spotlight when several new vaccines were authorised and rolled out as a response to the COVID-19 pandemic.The anticipated extent of the global vaccine rollout stressed the importance of a well-functioning safety surveillance system and international collaborations between patients, health care workers, vaccine producers, regulatory authorities, and PV centres.The identification and communication of potential safety concerns showed that adaptations to PV processes made in a short period of time as well as international collaborations were successful. However, it is important to learn from experiences made so far and to make sure the positive advances are maintained in the future to advance medicines' safety together.

15.
Biomed Microdevices ; 13(2): 375-81, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21190086

RESUMO

We present a maskless micropatterning system that utilizes a fluorescence microscope with programmable X-Y stage and dry film photoresist to realize feature sizes in the sub-millimeter range (40-700 µm). The method allows for flexible in-house maskless photolithography without a dedicated microfabrication facility and is well-suited for rapid prototyping of microfluidic channels, scaffold templates for protein/cell patterning or optically-guided cell encapsulation for biomedical applications.


Assuntos
Luz , Microscopia de Fluorescência/métodos , Microtecnologia/métodos , Técnicas Analíticas Microfluídicas , Impressão , Fatores de Tempo
16.
Vaccine X ; 9: 100122, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34746743

RESUMO

This study reviewed cases of appendicitis following administration of COVID-19 vaccines reported to VigiBase, the WHO database of individual case safety reports (ICSRs). Three hundred fifty-eight cases were identified, and disproportionate reporting was noted, with 329 calculated expected cases. Upon review, 24 ICSRs were excluded, so 334 unique ICSRs underwent clinical review from 19 countries. Forty-eight percent of ICSRs reported imaging and 69% noted surgical intervention. The cases were clinically coherent, with an apparent increase in reporting in the four days post-vaccination and a possible dose-response relationship. Appendicitis has been suggested as an adverse event of special interest post-vaccination against COVID-19 after a numerical increase in the vaccine arm of a clinical trial. The case series may be affected by differences in global patterns of reporting, and it is not possible to prove nor disprove causality from this case series. Global longitudinal studies are required to clarify any possible relationship.

17.
HSS J ; 17(3): 267-273, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34539266

RESUMO

Background: Total knee arthroplasty (TKA) demonstrates excellent durability using jig-based manual techniques (manual TKA [mTKA]), but significant rates of dissatisfaction remain. Modifications of mTKA techniques and TKA implant designs to improve outcomes have had minimal success. Studies comparing relative outcomes of mTKA and robotic-assisted TKA (raTKA) are limited. Purpose: This study sought to compare outcomes of mTKA and raTKA in patients at a single institution. Methods: We retrospectively reviewed all primary TKAs performed by 1 surgeon from 2015 to 2017. In all, 139 consecutive mTKAs (2015-2016) and 148 consecutive raTKAs (2016-2017) were included. No cases were excluded. Patient demographics, complications, readmission rates, and clinical and patient-reported outcomes were compared at a minimum of 1-year follow-up. A post hoc student t test and Pearson χ2 test were used for continuous and categorical data. Results: We found that mTKA patients compared with raTKA patients required significantly longer length of stay (LOS) (1.73 vs 1.18 days, respectively), greater morphine milligram equivalents consumption (89.6 vs 65.2, respectively), and increased physical therapy (PT) visits (13.0 vs 11.0, respectively) with increased 30-day readmission rates (4.3 vs 0.7%, respectively) that approached significance. Knee Injury and Osteoarthritis Outcome Score for Joint Replacement and the University of California at Los Angeles activity score did not differ significantly comparing raTKA with mTKA patients at 1 year. There were no differences in complication rates. Conclusion: Significant early clinical benefits were noted with raTKA, including lower opioid requirements, shorter LOS, and fewer PT visits when compared with mTKA. A reduction in 30-day readmission rates was noted with raTKA that was not significant. Excellent clinical results with similar patient-reported outcomes were noted in both groups at 1-year follow-up. Further prospective investigations at longer follow-up intervals comparing these techniques are warranted.

18.
Proc Inst Mech Eng H ; 235(8): 849-860, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33899568

RESUMO

One fifth of idiopathic clubfoot deformities cannot be fully corrected by Serial Ponseti casting and deformity recurs in 20%-30% of cases. To avoid x-ray exposure, the joints with largely unossified bones are diagnosed with magnetic resonance images (MRI). Typically, geometric measurements are made in the MRI planes; however, this method is inaccurate compared to measurements on three-dimensional (3D) models of the joint. More accurate measurements using the 3D bone shapes may be better at identifying differences between groups; and therefore, improve diagnosis. The entire set of shape features from MRI can be analysed simultaneously through statistical shape modelling (SSM) which assesses bone morphology of clubfoot in a more sensitive way. A method for SSM of the talus is developed in this study and the shape of the normal talus is compared with the one in clubfeet with residual deformity through both geometric measurements and SSM. Significant differences between two groups were found by both methods; and therefore, might contribute to improve diagnosis of clubfoot.


Assuntos
Pé Torto Equinovaro , Tálus , Moldes Cirúrgicos , Criança , Pé Torto Equinovaro/diagnóstico por imagem , Humanos , Lactente , Imageamento por Ressonância Magnética , Modelos Estatísticos , Radiografia , Tálus/diagnóstico por imagem , Resultado do Tratamento
19.
Cell Rep ; 35(2): 108966, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33852868

RESUMO

Persistent virus infections can cause pathogenesis that is debilitating or lethal. During these infections, virus-specific T cells fail to protect due to weakened antiviral activity or failure to persist. These outcomes are governed by histone modifications, although it is unknown which enzymes contribute to T cell loss or impaired function over time. In this study, we show that T cell receptor-stimulated CD8+ T cells increase their expression of UTX (ubiquitously transcribed tetratricopeptide repeat, X chromosome) to enhance gene expression. During chronic lymphocytic choriomeningitis virus (LCMV) infection in mice, UTX binds to enhancers and transcription start sites of effector genes, allowing for improved cytotoxic T lymphocyte (CTL)-mediated protection, independent of its trimethylation of histone 3 lysine 27 (H3K27me3) demethylase activity. UTX also limits the frequency and durability of virus-specific CD8+ T cells, which correspond to increased expression of inhibitory receptors. Thus, UTX guides gene expression patterns in CD8+ T cells, advancing early antiviral defenses while reducing the longevity of CD8+ T cell responses.


Assuntos
Citotoxicidade Imunológica/genética , Histona Desmetilases/genética , Memória Imunológica/genética , Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Receptor Celular 2 do Vírus da Hepatite A/genética , Receptor Celular 2 do Vírus da Hepatite A/imunologia , Histona Desmetilases/deficiência , Histona Desmetilases/imunologia , Histonas/genética , Histonas/imunologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Coriomeningite Linfocítica/patologia , Vírus da Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Transdução de Sinais , Linfócitos T Citotóxicos/virologia , Carga Viral/genética , Carga Viral/imunologia , Proteína do Gene 3 de Ativação de Linfócitos
20.
Sci Rep ; 11(1): 22599, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34799577

RESUMO

Bacterial antibiotic resistance is an important global health threat and the interfaces of antibiotic resistance between humans, animals and the environment are complex. We aimed to determine the associations and overtime trends of antibiotic resistance between humans, animals and water sources from the same area and time and estimate attribution of the other sources to cases of human antibiotic resistance. A total of 125 children (aged 1-3 years old) had stool samples analysed for antibiotic-resistant bacteria at seven time points over two years, with simultaneous collection of samples of animal stools and water sources in a rural Indian community. Newey-West regression models were used to calculate temporal associations, the source with the most statistically significant relationships was household drinking water. This is supported by use of SourceR attribution modelling, that estimated the mean attribution of cases of antibiotic resistance in the children from animals, household drinking water and wastewater, at each time point and location, to be 12.6% (95% CI 4.4-20.9%), 12.1% (CI 3.4-20.7%) and 10.3% (CI 3.2-17.3%) respectively. This underlines the importance of the 'one health' concept and requires further research. Also, most of the significant trends over time were negative, suggesting a possible generalised improvement locally.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Animais , Bactérias/efeitos dos fármacos , Pré-Escolar , Água Potável , Escherichia coli/efeitos dos fármacos , Fezes/microbiologia , Humanos , Índia/epidemiologia , Lactente , Testes de Sensibilidade Microbiana , Estudos Prospectivos , Análise de Regressão , População Rural , Águas Residuárias
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