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1.
Nucleic Acids Res ; 51(D1): D488-D508, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36420884

RESUMO

The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB), founding member of the Worldwide Protein Data Bank (wwPDB), is the US data center for the open-access PDB archive. As wwPDB-designated Archive Keeper, RCSB PDB is also responsible for PDB data security. Annually, RCSB PDB serves >10 000 depositors of three-dimensional (3D) biostructures working on all permanently inhabited continents. RCSB PDB delivers data from its research-focused RCSB.org web portal to many millions of PDB data consumers based in virtually every United Nations-recognized country, territory, etc. This Database Issue contribution describes upgrades to the research-focused RCSB.org web portal that created a one-stop-shop for open access to ∼200 000 experimentally-determined PDB structures of biological macromolecules alongside >1 000 000 incorporated Computed Structure Models (CSMs) predicted using artificial intelligence/machine learning methods. RCSB.org is a 'living data resource.' Every PDB structure and CSM is integrated weekly with related functional annotations from external biodata resources, providing up-to-date information for the entire corpus of 3D biostructure data freely available from RCSB.org with no usage limitations. Within RCSB.org, PDB structures and the CSMs are clearly identified as to their provenance and reliability. Both are fully searchable, and can be analyzed and visualized using the full complement of RCSB.org web portal capabilities.


Assuntos
Inteligência Artificial , Bases de Dados de Proteínas , Proteínas , Aprendizado de Máquina , Conformação Proteica , Proteínas/química , Reprodutibilidade dos Testes
2.
J Pediatr ; 269: 113973, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38401785

RESUMO

OBJECTIVE: To test whether different clinical decision support tools increase clinician orders and patient completions relative to standard practice and each other. STUDY DESIGN: A pragmatic, patient-randomized clinical trial in the electronic health record was conducted between October 2019 and April 2020 at Geisinger Health System in Pennsylvania, with 4 arms: care gap-a passive listing recommending screening; alert-a panel promoting and enabling lipid screen orders; both; and a standard practice-no guideline-based notification-control arm. Data were analyzed for 13 346 9- to 11-year-old patients seen within Geisinger primary care, cardiology, urgent care, or nutrition clinics, or who had an endocrinology visit. Principal outcomes were lipid screening orders by clinicians and completions by patients within 1 week of orders. RESULTS: Active (care gap and/or alert) vs control arm patients were significantly more likely (P < .05) to have lipid screening tests ordered and completed, with ORs ranging from 1.67 (95% CI 1.28-2.19) to 5.73 (95% CI 4.46-7.36) for orders and 1.54 (95% CI 1.04-2.27) to 2.90 (95% CI 2.02-4.15) for completions. Alerts, with or without care gaps listed, outperformed care gaps alone on orders, with odds ratios ranging from 2.92 (95% CI 2.32-3.66) to 3.43 (95% CI 2.73-4.29). CONCLUSIONS: Electronic alerts can increase lipid screening orders and completions, suggesting clinical decision support can improve guideline-concordant screening. The study also highlights electronic record-based patient randomization as a way to determine relative effectiveness of support tools. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04118348.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Programas de Rastreamento , Humanos , Criança , Masculino , Feminino , Programas de Rastreamento/métodos , Lipídeos/sangue , Registros Eletrônicos de Saúde
3.
Nucleic Acids Res ; 50(20): 11550-11562, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36330958

RESUMO

The honey bee genome has the capacity to produce three phenotypically distinct organisms (two diploid female castes: queen and worker, and a haploid male drone). Previous studies have implicated metabolic flux acting via epigenetic regulation in directing nutrition-driven phenotypic plasticity in the honey bee. However, the cis-acting DNA regulatory elements that establish tissue and polyphenism -specific epigenomes and gene expression programmes, remain unclear. Using a high resolution multiomic approach including assay for transposase-accessible chromatin by sequencing (ATAC-seq), RNA-seq and ChIP-seq, we produce the first genome-wide maps of the regulatory landscape across all three adult honey bee phenotypes identifying > 5000 regulatory regions in queen, 7500 in worker and 6500 in drone, with the vast majority of these sites located within intronic regions. These regions are defined by positive enrichment of H3K27ac and depletion of H3K4me3 and show a positive correlation with gene expression. Using ATAC-seq footprinting we determine queen, worker and drone -specific transcription factor occupancy and uncover novel phenotype-specific regulatory networks identifying two key nuclear receptors that have previously been implicated in caste-determination and adult behavioural maturation in honey bees; ecdysone receptor and ultraspiracle. Collectively, this study provides novel insights into key gene regulatory networks that are associated with these distinct polyphenisms in the honey bee.


Assuntos
Abelhas , Encéfalo , Cromatina , Redes Reguladoras de Genes , Animais , Feminino , Masculino , Abelhas/genética , Cromatina/genética , Cromatina/metabolismo , Epigênese Genética , Larva/genética
4.
Nucleic Acids Res ; 50(6): e33, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-34908129

RESUMO

Despite a vast expansion in the availability of epigenomic data, our knowledge of the chromatin landscape at interspersed repeats remains highly limited by difficulties in mapping short-read sequencing data to these regions. In particular, little is known about the locus-specific regulation of evolutionarily young transposable elements (TEs), which have been implicated in genome stability, gene regulation and innate immunity in a variety of developmental and disease contexts. Here we propose an approach for generating locus-specific protein-DNA binding profiles at interspersed repeats, which leverages information on the spatial proximity between repetitive and non-repetitive genomic regions. We demonstrate that the combination of HiChIP and a newly developed mapping tool (PAtChER) yields accurate protein enrichment profiles at individual repetitive loci. Using this approach, we reveal previously unappreciated variation in the epigenetic profiles of young TE loci in mouse and human cells. Insights gained using our method will be invaluable for dissecting the molecular determinants of TE regulation and their impact on the genome.


Assuntos
Cromatina , Elementos de DNA Transponíveis , Animais , Cromatina/genética , Elementos de DNA Transponíveis/genética , Regulação da Expressão Gênica , Genômica , Humanos , Camundongos
5.
Bioinformatics ; 38(5): 1452-1454, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-34864908

RESUMO

MOTIVATION: Membrane proteins are encoded by approximately one fifth of human genes but account for more than half of all US FDA approved drug targets. Thanks to new technological advances, the number of membrane proteins archived in the PDB is growing rapidly. However, automatic identification of membrane proteins or inference of membrane location is not a trivial task. RESULTS: We present recent improvements to the RCSB Protein Data Bank web portal (RCSB PDB, rcsb.org) that provide a wealth of new membrane protein annotations integrated from four external resources: OPM, PDBTM, MemProtMD and mpstruc. We have substantially enhanced the presentation of data on membrane proteins. The number of membrane proteins with annotations available on rcsb.org was increased by ∼80%. Users can search for these annotations, explore corresponding tree hierarchies, display membrane segments at the 1D amino acid sequence level, and visualize the predicted location of the membrane layer in 3D. AVAILABILITY AND IMPLEMENTATION: Annotations, search, tree data and visualization are available at our rcsb.org web portal. Membrane visualization is supported by the open-source Mol* viewer (molstar.org and github.com/molstar/molstar). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Proteínas de Membrana , Software , Humanos , Conformação Proteica , Bases de Dados de Proteínas , Sequência de Aminoácidos
6.
Soft Matter ; 19(26): 4964-4971, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37342008

RESUMO

Repairable adhesive elastomers are emerging materials employed in compelling applications such as soft robotics, biosensing, tissue regeneration, and wearable electronics. Facilitating adhesion requires strong interactions, while self-healing requires bond dynamicity. This contrast in desired bond characteristics presents a challenge in the design of healable adhesive elastomers. Furthermore, 3D printability of this novel class of materials has received limited attention, restricting the potential design space of as-built geometries. Here, we report a series of 3D-printable elastomeric materials with self-healing ability and adhesive properties. Repairability is obtained using Thiol-Michael dynamic crosslinkers incorporated into the polymer backbone, while adhesion is facilitated with acrylate monomers. Elastomeric materials with excellent elongation up to 2000%, self-healing stress recovery >95%, and strong adhesion with metallic and polymeric surfaces are demonstrated. Complex functional structures are successfully 3D printed using a commercial digital light processing (DLP) printer. Shape-selective lifting of low surface energy poly(tetrafluoroethylene) objects is achieved using soft robotic actuators with interchangeable 3D-printed adhesive end effectors, wherein tailored contour matching leads to increased adhesion and successful lifting capacity. The demonstrated utility of these adhesive elastomers provides unique capabilities to easily program soft robot functionality.

7.
Nucleic Acids Res ; 49(D1): D437-D451, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33211854

RESUMO

The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB), the US data center for the global PDB archive and a founding member of the Worldwide Protein Data Bank partnership, serves tens of thousands of data depositors in the Americas and Oceania and makes 3D macromolecular structure data available at no charge and without restrictions to millions of RCSB.org users around the world, including >660 000 educators, students and members of the curious public using PDB101.RCSB.org. PDB data depositors include structural biologists using macromolecular crystallography, nuclear magnetic resonance spectroscopy, 3D electron microscopy and micro-electron diffraction. PDB data consumers accessing our web portals include researchers, educators and students studying fundamental biology, biomedicine, biotechnology, bioengineering and energy sciences. During the past 2 years, the research-focused RCSB PDB web portal (RCSB.org) has undergone a complete redesign, enabling improved searching with full Boolean operator logic and more facile access to PDB data integrated with >40 external biodata resources. New features and resources are described in detail using examples that showcase recently released structures of SARS-CoV-2 proteins and host cell proteins relevant to understanding and addressing the COVID-19 global pandemic.


Assuntos
Biologia Computacional/métodos , Bases de Dados de Proteínas , Substâncias Macromoleculares/química , Conformação Proteica , Proteínas/química , Bioengenharia/métodos , Pesquisa Biomédica/métodos , Biotecnologia/métodos , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Humanos , Substâncias Macromoleculares/metabolismo , Pandemias , Proteínas/genética , Proteínas/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiologia , Software , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo
8.
Cochrane Database Syst Rev ; 10: CD012450, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36269125

RESUMO

BACKGROUND: Corticosteroids are medications with anti-inflammatory and immunosuppressant properties. Systemic corticosteroids administered through the oral, intravenous, or intramuscular routes have been used to treat various types of low back pain, including radicular back pain (not due to spinal stenosis), non-radicular back pain, and spinal stenosis. However, there is uncertainty about the benefits and harms of systemic corticosteroids for low back pain. OBJECTIVES: To evaluate the benefits and harms of systemic corticosteroids versus placebo or no corticosteroid for radicular low back pain, non-radicular low back pain, and symptomatic spinal stenosis in adults. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was September 2021. SELECTION CRITERIA: We included randomized and quasi-randomized trials in adults of systematic corticosteroids versus placebo or no corticosteroid. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. The major outcomes were pain, function, need for surgery, serious adverse effect, and presence of hyperglycemia. The minor outcomes were quality of life, successful outcomes, non-serious adverse events, and withdrawal due to adverse events. We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: Thirteen trials (1047 participants) met the inclusion criteria. Nine trials included participants with radicular low back pain, two trial with low back pain, and two trials with spinal stenosis. All trials blinded participants to receipt of systemic corticosteroids. Seven trials were at low risk of bias, five at unclear risk, and one at high risk of selection bias. Two trials were at high risk of attrition bias. Doses and duration of systemic corticosteroid therapy varied. Radicular low back pain For radicular low back pain, moderate-certainty evidence indicated that systemic corticosteroids probably slightly decrease pain versus placebo at short-term follow-up (mean difference (MD) 0.56 points better, 95% confidence interval (CI) 1.08 to 0.04 on a 0 to 10 scale) and may slightly increase the likelihood of experiencing improvement in pain at short-term follow-up (risk ratio (RR) 1.21, 95% CI 0.88 to 1.66; absolute effect 5% better (95% CI 5% worse to 15% better). Systemic corticosteroids may not improve function at short-term follow-up (standardized mean difference (SMD) 0.14 better; range 0.49 better to 0.21 worse) and probably increase the likelihood of improvement in function at short-term follow-up (RR 1.52, 95% CI 1.22 to 1.91; absolute effect 19% better, 95% CI 8% better to 30% better). Systemic corticosteroids were associated with greater improvement in function versus placebo at long-term follow-up (MD -7.40, 95% CI -12.55 to -2.25 on the 0 to 100 Oswestry Disability Index) and greater likelihood of functional improvement (RR 1.29, 95% CI 1.06 to 1.56), based on a single trial. There was no difference in likelihood of surgery (RR 1.00, 95% CI 0.68 to 1.47). Evidence indicated that systemic corticosteroids (administered as a single dose or as a short course of therapy) are not associated with increased risk of any adverse event, serious adverse events, withdrawal due to adverse events, or hyperglycemia, but estimates were imprecise as some trials did not report harms, and harms reporting was suboptimal in trials that did provide data. Limitations included variability across trials in interventions (e.g. corticosteroid used, dose and duration of treatment), clinical settings, and participants (e.g. duration of symptoms, methods for diagnosis); limited utility of subgroup analyses due to small numbers of trials; methodologic limitations or suboptimal reporting of methods by some trials; and too few trials to formally assess for publication bias using graphical or statistical tests for small sample effects. Non-radicular low back pain Evidence on systemic corticosteroids versus placebo for non-radicular pain was limited and suggested that systemic corticosteroids may be associated with slightly worse short-term pain but slightly better function. Spinal stenosis For spinal stenosis, limited evidence indicated that systemic corticosteroids are probably no more effective than placebo for short-term pain or function. AUTHORS' CONCLUSIONS: Systemic corticosteroids appear to be slightly effective at improving short-term pain and function in people with radicular low back pain not due to spinal stenosis, and might slightly improve long-term function. The effects of systemic corticosteroids in people with non-radicular low back pain are unclear and systemic corticosteroids are probably ineffective for spinal stenosis. A single dose or short course of systemic corticosteroids for low back pain does not appear to cause serious harms, but evidence is limited.


Assuntos
Hiperglicemia , Dor Lombar , Estenose Espinal , Adulto , Humanos , Corticosteroides/efeitos adversos , Imunossupressores , Dor Lombar/tratamento farmacológico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Genome Res ; 28(10): 1532-1542, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30135090

RESUMO

The capacity of the honey bee to produce three phenotypically distinct organisms (two female castes; queens and sterile workers, and haploid male drones) from one genotype represents one of the most remarkable examples of developmental plasticity in any phylum. The queen-worker morphological and reproductive divide is environmentally controlled during post-embryonic development by differential feeding. Previous studies implicated metabolic flux acting via epigenetic regulation, in particular DNA methylation and microRNAs, in establishing distinct patterns of gene expression underlying caste-specific developmental trajectories. We produce the first genome-wide maps of chromatin structure in the honey bee at a key larval stage in which developmental canalization into queen or worker is virtually irreversible. We find extensive genome-wide differences in H3K4me3, H3K27ac, and H3K36me3, many of which correlate with caste-specific transcription. Furthermore, we identify H3K27ac as a key chromatin modification, with caste-specific regions of intronic H3K27ac directing the worker caste. These regions may harbor the first examples of caste-specific enhancer elements in the honey bee. Our results demonstrate a key role for chromatin modifications in the establishment and maintenance of caste-specific transcriptional programs in the honey bee. We show that at 96 h of larval growth, the queen-specific chromatin pattern is already established, whereas the worker determination is not, thus providing experimental support for the perceived timing of this critical point in developmental heterochrony in two types of honey bee females. In a broader context, our study provides novel data on environmentally regulated organismal plasticity and the molecular foundation of the evolutionary origins of eusociality.


Assuntos
Abelhas/crescimento & desenvolvimento , Cromatina/genética , Epigênese Genética , Proteínas de Insetos/genética , Animais , Abelhas/genética , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , Imunoprecipitação da Cromatina , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Histonas/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento , Masculino , Fenótipo , Análise de Sequência de DNA , Análise de Sequência de RNA
10.
Crit Care Med ; 49(10): 1739-1748, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34115635

RESUMO

OBJECTIVES: The coronavirus disease 2019 pandemic has overwhelmed healthcare resources even in wealthy nations, necessitating rationing of limited resources without previously established crisis standards of care protocols. In Massachusetts, triage guidelines were designed based on acute illness and chronic life-limiting conditions. In this study, we sought to retrospectively validate this protocol to cohorts of critically ill patients from our hospital. DESIGN: We applied our hospital-adopted guidelines, which defined severe and major chronic conditions as those associated with a greater than 50% likelihood of 1- and 5-year mortality, respectively, to a critically ill patient population. We investigated mortality for the same intervals. SETTING: An urban safety-net hospital ICU. PATIENTS: All adults hospitalized during April of 2015 and April 2019 identified through a clinical database search. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 365 admitted patients, 15.89% had one or more defined chronic life-limiting conditions. These patients had higher 1-year (46.55% vs 13.68%; p < 0.01) and 5-year (50.00% vs 17.22%; p < 0.01) mortality rates than those without underlying conditions. Irrespective of classification of disease severity, patients with metastatic cancer, congestive heart failure, end-stage renal disease, and neurodegenerative disease had greater than 50% 1-year mortality, whereas patients with chronic lung disease and cirrhosis had less than 50% 1-year mortality. Observed 1- and 5-year mortality for cirrhosis, heart failure, and metastatic cancer were more variable when subdivided into severe and major categories. CONCLUSIONS: Patients with major and severe chronic medical conditions overall had 46.55% and 50.00% mortality at 1 and 5 years, respectively. However, mortality varied between conditions. Our findings appear to support a crisis standards protocol which focuses on acute illness severity and only considers underlying conditions carrying a greater than 50% predicted likelihood of 1-year mortality. Modifications to the chronic lung disease, congestive heart failure, and cirrhosis criteria should be refined if they are to be included in future models.


Assuntos
COVID-19/terapia , Intervenção em Crise/normas , Alocação de Recursos/métodos , Centros Médicos Acadêmicos/organização & administração , Centros Médicos Acadêmicos/estatística & dados numéricos , Adulto , COVID-19/epidemiologia , Intervenção em Crise/métodos , Intervenção em Crise/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Massachusetts , Pessoa de Meia-Idade , Alocação de Recursos/estatística & dados numéricos , Estudos Retrospectivos , Provedores de Redes de Segurança/organização & administração , Provedores de Redes de Segurança/estatística & dados numéricos , Padrão de Cuidado/normas , Padrão de Cuidado/estatística & dados numéricos , População Urbana/estatística & dados numéricos
11.
Gastrointest Endosc ; 94(1): 60-67.e1, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33385462

RESUMO

BACKGROUND AND AIMS: Portal pressure can be used to identify patients with chronic liver disease who have progressed to cirrhosis. Portal pressure can also provide accurate prognostication for patients with cirrhosis. However, there are no practical means for assessment of portal pressure. Although it is well established that the gastric mucosal blood supply increases in patients with cirrhosis, this has been difficult to quantify reproducibly. Our group has developed a novel spectroscopic technology called spatially resolved subdiffuse reflectance spectroscopy (SRSRS), which enables quantification of mucosal microcirculation. We aim to ascertain if quantification of the gastric mucosal microcirculation with SRSRS correlates with clinical evidence of portal hypertension. METHODS: Patients undergoing EGD for clinical indications had 10 measurements taken in the endoscopically normal gastric fundus via SRSRS probe to assess the microcirculation. Cases were defined as patients with cirrhosis (n = 18), and controls were those without evidence of liver disease (n = 18); this was corroborated with transient elastography. RESULTS: The blood volume fraction (P = .06) and subdiffuse reflectance (P = .02) from a shallow depth in the gastric fundus were higher in patients with cirrhosis than those without. These markers were combined to yield an overall optical marker that can differentiate patients with cirrhosis from controls with a sensitivity of 72% and specificity of 94% (area under receiver operating curve, 0.82). CONCLUSIONS: Spectroscopic quantification of gastric fundal mucosal microcirculation is a promising surrogate of clinical correlates of portal hypertension. This approach may represent a less-intrusive surrogate biomarker for liver disease prognostication and potentially response to therapy.


Assuntos
Hipertensão Portal , Biomarcadores , Mucosa Gástrica , Humanos , Hipertensão Portal/diagnóstico por imagem , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Microcirculação , Análise Espectral
12.
Prehosp Emerg Care ; 25(4): 596, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909527

RESUMO

This is the official position statement of the National Association of EMS Physicians on the role of emergency medical services (EMS) in disaster response.


Assuntos
Desastres , Serviços Médicos de Emergência , Médicos , Humanos
13.
Nucleic Acids Res ; 47(D1): D464-D474, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30357411

RESUMO

The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB, rcsb.org), the US data center for the global PDB archive, serves thousands of Data Depositors in the Americas and Oceania and makes 3D macromolecular structure data available at no charge and without usage restrictions to more than 1 million rcsb.org Users worldwide and 600 000 pdb101.rcsb.org education-focused Users around the globe. PDB Data Depositors include structural biologists using macromolecular crystallography, nuclear magnetic resonance spectroscopy and 3D electron microscopy. PDB Data Consumers include researchers, educators and students studying Fundamental Biology, Biomedicine, Biotechnology and Energy. Recent reorganization of RCSB PDB activities into four integrated, interdependent services is described in detail, together with tools and resources added over the past 2 years to RCSB PDB web portals in support of a 'Structural View of Biology.'


Assuntos
Bases de Dados de Proteínas , Conformação Proteica , Pesquisa Biomédica/educação , Biotecnologia/educação , Curadoria de Dados , Software
14.
Vet Ophthalmol ; 24(1): 48-58, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33034144

RESUMO

PURPOSE: To report surgical and corneal clarity scores (CCSs) of corneo-limbo-conjunctival transpositions (CLCTs) in a large number of canine cases. METHODS: Retrospective review of records that underwent CLCT to repair deep ulcers or perforations between 2002 and 2018. Signalment, concurrent eye disease, additional procedures, pathogenesis, medication, graft orientation, follow-up, and CCSs were recorded. RESULTS: 418 eyes of 399 dogs were included. Brachycephalics were most commonly affected, comprising 325/418 (77.75%) of the eyes. The most commonly affected breeds were Pugs, Shih Tzus, Cavalier King Charles Spaniels, and French Bulldogs, with 116/418 (27.75%), 64/418 (15.31%), 34/418 (8.13%), and 34/418 (8.13%) ulcerated eyes, respectively. Mean age at surgery was 5.5 years (range 59 days-17.7 years), and median follow-up time was 100 days (range 3 days-7.64 years). The most common etiopathogenesis was spontaneous ulceration in 205/418 eyes (49.04%) of which 191 (93.17%) occurred in brachycephalics. Primary keratoconjunctivitis sicca affected 122/418 eyes (29.19%) and injury 39/418 eyes (9.33%). Mean ulcer width was 3.5 mm (0.5-10 mm). Success rate was 97.13% (406/418 eyes). Failure end points recorded included no menace response, secondary glaucoma, and endophthalmitis. Pre-existing perforation was found in 101/418 (24.16%) of the eyes and significantly increased failure rate (P < .001). The median CCS was G3 (G0-G4), which was lower for Pugs (G2). Graft orientation affected CCS, but did not reach statistical significance. CONCLUSION: The high success rate and CCS for CLCT in dogs make it a good technique to treat deep ulcers but a less desirable outcome is anticipated when treating perforations and Pugs.


Assuntos
Transplante de Córnea/veterinária , Úlcera da Córnea/veterinária , Doenças do Cão/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/veterinária , Animais , Túnica Conjuntiva/cirurgia , Túnica Conjuntiva/transplante , Córnea/cirurgia , Transplante de Córnea/métodos , Úlcera da Córnea/cirurgia , Cães , Feminino , Limbo da Córnea/cirurgia , Masculino , Procedimentos Cirúrgicos Oftalmológicos/métodos , Cuidados Pós-Operatórios/veterinária , Estudos Retrospectivos , Resultado do Tratamento
15.
Bioorg Med Chem ; 28(9): 115442, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32209295

RESUMO

A unified synthetic approach was developed that enabled the synthesis of diverse tropane-related scaffolds. The key intermediates that were exploited were cycloadducts formed by reaction between 3-hydroxy-pyridinium salts and vinyl sulfones or sulfonamides. The diverse tropane-related scaffolds were formed by addition of substituents to, cyclisation reactions of, and fusion of additional ring(s) to the key bicyclic intermediates. A set of 53 screening compounds was designed, synthesised and evaluated in order to determine the biological relevance of the scaffolds accessible using the synthetic approach. Two inhibitors of Hedgehog signalling, and four compounds with weak activity against the parasite P. falciparum, were discovered. Three of the active compounds may be considered to be indotropane or pyrrotropane pseudo natural products in which a tropane is fused with a fragment from another natural product class. It was concluded that the unified synthetic approach had yielded diverse scaffolds suitable for the design of performance-diverse screening libraries.


Assuntos
Antimaláricos/farmacologia , Proteínas Hedgehog/antagonistas & inibidores , Plasmodium falciparum/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Tropanos/farmacologia , Antimaláricos/síntese química , Antimaláricos/química , Proteínas Hedgehog/metabolismo , Estrutura Molecular , Testes de Sensibilidade Parasitária , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Tropanos/síntese química , Tropanos/química
16.
Vet Ophthalmol ; 23(6): 930-942, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32893460

RESUMO

PURPOSE: To describe a modified keratoleptynsis procedure, as a method of preserving central corneal function, and evaluate the outcome in vision, reduction of corneal thickness and treatment of epithelial corneal ulcers in cases with endothelial cell dysfunction. METHODS: Forty-four dogs (72 eyes) were affected by progressive corneal edema, with or without ulcerative keratitis. All patients were treated with a dorsal and ventral superficial keratectomy followed by conjunctival flaps, maintaining a clear central cornea. Corneal thickness measurements were obtained via ultrasound biomicroscopy. RESULTS: All eyes showed resolution of ocular discomfort postoperatively, with a median time to resolution of 35 days. Two years post-surgery, vision had been lost in 2 of 29 eyes (7%). From the initial population, 23 dogs (39 eyes) had follow-up evaluations of corneal thickness. The mean central corneal thickness was 1359 ± 251 µm prior to surgery. Thickening of the central cornea was observed one week after surgery to 1559 ± 263 µm. Decreased corneal thickness was reported, at 1 month, 4 months, 10 months and 2 years postoperatively (1285 ± 267 µm, 1102 ± 150 µm, 1121 ± 288 µm, 1193 ± 283 µm, respectively). All eyes showed a similar trend of increasing and then decreasing corneal thickness. CONCLUSIONS: This surgical technique provided statistically significant reduction in central corneal thickness and sustained relief of ocular pain. Reduction in corneal thickness appeared to be maintained 2 years post-surgery, and all patients remained comfortable. Superficial corneal pigmentation and fibrosis resulted in vision loss in two eyes.


Assuntos
Edema da Córnea/veterinária , Úlcera da Córnea/veterinária , Doenças do Cão/cirurgia , Ceratectomia/veterinária , Animais , Edema da Córnea/cirurgia , Paquimetria Corneana/veterinária , Úlcera da Córnea/cirurgia , Cães , Feminino , Masculino , Estudos Retrospectivos , Resultado do Tratamento
17.
Hum Mol Genet ; 26(8): 1552-1564, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28207045

RESUMO

Solid tumours have oxygen gradients and areas of near and almost total anoxia. Hypoxia reduces sensitivity to 5-fluorouracil (5-FU)-chemotherapy for colorectal cancer (CRC). MicroRNAs (miRNAs) are hypoxia sensors and were altered consistently in six CRC cell lines (colon cancer: DLD-1, HCT116 and HT29; rectal cancer: HT55, SW837 and VACO4S) maintained in hypoxia (1 and 0.2% oxygen) compared with normoxia (20.9%). CRC cell lines also showed altered amino acid metabolism in hypoxia and hypoxia-responsive miRNAs were predicted to target genes in four metabolism pathways: beta-alanine; valine, leucine, iso-leucine; aminoacyl-tRNA; and alanine, aspartate, glutamate. MiR-210 was increased in hypoxic areas of CRC tissues and hypoxia-responsive miR-21 and miR-30d, but not miR-210, were significantly increased in 5-FU resistant CRCs. Treatment with miR-21 and miR-30d antagonists sensitized hypoxic CRC cells to 5-FU. Our data highlight the complexity and tumour heterogeneity caused by hypoxia. MiR-210 as a hypoxic biomarker, and the targeting of miR-21 and miR-30d and/or the amino acid metabolism pathways may offer translational opportunities.


Assuntos
Neoplasias Colorretais/genética , MicroRNAs/biossíntese , Aminoácidos/metabolismo , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Fluoruracila/administração & dosagem , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Heterogeneidade Genética , Células HCT116 , Humanos , MicroRNAs/genética , Oxigênio/metabolismo
18.
Exp Eye Res ; 187: 107755, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31408630

RESUMO

Dark-rearing has been found to slow the rate of retinal degeneration in albino P23H but not S334ter mutant rhodopsin transgenic (Tg) rats. Since eye pigmentation has the same protective slowing effect as dark-rearing in RCS rats, we examined whether eye pigmentation has a comparable slowing effect in the different mutant rhodopsin Tg rats. Different lines of albino P23H and S334ter Tg rats on the Sprague-Dawley (SD) background were bred to Long-Evans (LE) rats to produce pigmented Tg rats. These were compared to albino Tg rats at postnatal days of different ages using the outer nuclear layer (ONL) as a morphological measure of photoreceptor number and electroretinogram (ERG) a- and b-wave amplitudes as a measure of retinal function. When compared to albino P23H rats, pigmented P23H rats had a slower rate of degeneration as measured by greater ONL thicknesses and greater ERG a- and b-wave amplitudes. By contrast, pigmented S334ter rats showed no difference in ONL thicknesses or ERG a- and b-wave amplitudes when compared to their albino equivalents. Thus, degeneration of photoreceptors in P23H Tg rats is slowed by eye pigmentation as measured by ONL thickness, while it is not in the S334ter Tg rats. Eye pigmentation also protects functional changes in ERG a- and b-waves for the P23H lines, but not for the S334ter lines.


Assuntos
Cor de Olho/genética , Retina/fisiopatologia , Degeneração Retiniana/genética , Degeneração Retiniana/fisiopatologia , Rodopsina/genética , Animais , Eletrorretinografia , Mutação , Fenótipo , Células Fotorreceptoras de Vertebrados/patologia , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Ratos Transgênicos
19.
Vet Pathol ; 56(3): 460-464, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30686121

RESUMO

This report describes the clinical presentation, diagnosis, and histopathologic features of oculodermal melanocytosis in a young dog. A 3-year-old male neutered Labrador Retriever presented with conjunctival and scleral hyperpigmentation of the right eye, with concurrent ipsilateral cutaneous hyperpigmentation involving the right side of the face. Initial skin and conjunctival biopsies revealed an accumulation of histologically benign melanocytes within the dermis and conjunctival stroma, respectively. Enucleation was elected 19 months later by the referring veterinarian due to the progression of ocular pigmentation with concurrent marked corneal lipidosis and the suspicion of a scleral mass. On gross and histopathologic examination of the globe, there was marked panuveal melanocytosis with extension into the sclera, bulbar conjunctiva, and connective tissue surrounding the optic nerve, as well as sharply demarcated ipsilateral hyperpigmentation of the facial skin. The findings are characteristic of oculodermal melanocytosis (nevus of Ota), a dermal melanocytic hamartoma presenting as cutaneous facial hyperpigmentation that corresponds to the distribution of the ophthalmic and maxillary branches of the trigeminal nerve, often with ipsilateral ocular involvement.


Assuntos
Doenças do Cão/patologia , Neoplasias Oculares/veterinária , Nevo de Ota/veterinária , Neoplasias Cutâneas/veterinária , Animais , Túnica Conjuntiva/patologia , Doenças do Cão/diagnóstico , Cães , Neoplasias Oculares/diagnóstico , Neoplasias Oculares/patologia , Masculino , Nevo de Ota/diagnóstico , Nevo de Ota/patologia , Esclera/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia
20.
Nucleic Acids Res ; 45(D1): D271-D281, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-27794042

RESUMO

The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB, http://rcsb.org), the US data center for the global PDB archive, makes PDB data freely available to all users, from structural biologists to computational biologists and beyond. New tools and resources have been added to the RCSB PDB web portal in support of a 'Structural View of Biology.' Recent developments have improved the User experience, including the high-speed NGL Viewer that provides 3D molecular visualization in any web browser, improved support for data file download and enhanced organization of website pages for query, reporting and individual structure exploration. Structure validation information is now visible for all archival entries. PDB data have been integrated with external biological resources, including chromosomal position within the human genome; protein modifications; and metabolic pathways. PDB-101 educational materials have been reorganized into a searchable website and expanded to include new features such as the Geis Digital Archive.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Proteínas/química , Proteínas/genética , Conjuntos de Dados como Assunto , Redes e Vias Metabólicas , Modelos Moleculares , Conformação Proteica , Proteínas/metabolismo , Software , Relação Estrutura-Atividade , Interface Usuário-Computador , Navegador
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