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1.
Int Ophthalmol ; 42(7): 2117-2126, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34989951

RESUMO

PURPOSE: To determine through a feasibility study whether anterior and posterior corneal arc length and cross-sectional area measured using anterior segment ocular coherence tomography (AS-OCT) can distinguish between healthy and keratoconic corneas. METHODS: Patients diagnosed with keratoconus along with healthy controls underwent AS-OCT. ImageJ was used to determine the central 6 mm anterior and posterior corneal arc lengths and cross-sectional areas. Each length and area was then divided into 1-mm segment and relative differences compared. RESULTS: Twenty-five eyes from 15 patients with keratoconus, along with 25 eyes from 14 healthy controls were enrolled. There was a statistically significant difference in anterior and posterior corneal arc lengths as well as corneal cross-sectional area (p = 0.006, p = 0.005, p = 0.01, respectively). When selecting for the less advanced keratoconus eye, it was noted that posterior corneal arc length was longer in the paracentral temporal segment (1003 vs. 1010 µm, p = 0.04) and that greater change in corneal cross-sectional areas occurred between adjacent segments in less advanced keratoconus eyes. CONCLUSION: AS-OCT is capable of reliably measuring corneal arc lengths in patients with keratoconus and healthy patients. Both anterior and posterior corneal arc lengths along with central cross-sectional areas are statistically different between healthy and keratoconus eyes.


Assuntos
Ceratocone , Biometria , Córnea/diagnóstico por imagem , Topografia da Córnea/métodos , Humanos , Ceratocone/diagnóstico , Tomografia de Coerência Óptica/métodos
2.
Development ; 144(5): 844-855, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28126841

RESUMO

How differential levels of gene expression are controlled in post-mitotic neurons is poorly understood. In the Drosophila retina, expression of the transcription factor Defective Proventriculus (Dve) at distinct cell type-specific levels is required for terminal differentiation of color- and motion-detecting photoreceptors. Here, we find that the activities of two cis-regulatory enhancers are coordinated to drive dve expression in the fly eye. Three transcription factors act on these enhancers to determine cell-type specificity. Negative autoregulation by Dve maintains expression from each enhancer at distinct homeostatic levels. One enhancer acts as an inducible backup ('dark' shadow enhancer) that is normally repressed but becomes active in the absence of the other enhancer. Thus, two enhancers integrate combinatorial transcription factor input, feedback and redundancy to generate cell type-specific levels of dve expression and stable photoreceptor fate. This regulatory logic may represent a general paradigm for how precise levels of gene expression are established and maintained in post-mitotic neurons.


Assuntos
Diferenciação Celular , Drosophila melanogaster/genética , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Células Fotorreceptoras de Invertebrados/metabolismo , Proventrículo/embriologia , Animais , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriologia , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Homeodomínio/metabolismo , Homeostase , Mitose , Neurônios/metabolismo , Retina/embriologia , Retina/metabolismo , Rodopsina/metabolismo , Fatores de Transcrição/metabolismo
3.
Am J Gastroenterol ; 111(9): 1297-304, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27325221

RESUMO

OBJECTIVES: Data from the United States are lacking regarding the impact of entecavir (ETV) on the risk of hepatocellular carcinoma (HCC). Our aim is to determine whether treatment with ETV is associated with a reduced HCC risk by calculating the expected HCC incidence based on the Risk Estimation for Hepatocellular Carcinoma in Chronic Hepatitis B (REACH-B) model and comparing it with the observed HCC incidence. METHODS: The incidence of HCC in US patients treated with ETV between 2005 and 2013 in a retrospective cohort was obtained. The predicted HCC incidence was calculated using the REACH-B model. The standardized incidence ratios (SIRs) were calculated as a ratio of observed over predicted HCC cases. RESULTS: Of 841 patients, 646 (65% male, 84% Asian, median age 47 years, 36% hepatitis B e antigen positive, 9.4% with cirrhosis) met the inclusion criteria. Over a median follow-up of 4 years, 17 (2.6%) cases of HCC were diagnosed, including 8 out of 61 (13.1%) patients with cirrhosis and 9 out of 585 (1.5%) without cirrhosis. Compared with those without HCC, the 17 patients with HCC were older at 53 years vs. 47 years and more likely to have cirrhosis at 47.1% vs. 8.4%. Among patients without cirrhosis, the observed HCC incidence was significantly lower than predicted by the fourth year (SIR, 0.37; 95% confidence interval: 0.166-0.82). A sensitivity analysis that comprised all patients, including those with cirrhosis, showed that at the maximum follow-up time of 8.2 years, a significantly lower than predicted HCC incidence was noted with an SIR of 0.56 (95% confidence interval: 0.35-0.905). CONCLUSIONS: Based on the REACH-B model, long-term ETV therapy was associated with a lower than predicted HCC incidence. However, the risk of HCC persisted, and careful HCC surveillance remains warranted despite the anti-viral treatment.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Guanina/uso terapêutico , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/complicações , Hepatite B Crônica/epidemiologia , Humanos , Incidência , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos/epidemiologia , Adulto Jovem
4.
Am J Case Rep ; 25: e943166, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38425030

RESUMO

BACKGROUND Pneumatosis intestinalis (PI) is an uncommon condition that is not specific to any particular disease. Currently, there is no specific clinical guideline for treating and diagnosing PI. Furthermore, there are numerous causes of PI, which makes it difficult for clinicians - internal medicine physicians as well as surgeons - to take a clinical approach to diagnosis and treatment. CASE REPORT We present 3 clinical scenarios with PI. In the first patient there was a solitary image of PI, which was treated successfully with parenteral nutrition and intravenous antibiotics, and he was discharged after 5 days. The other 2 cases, which involve gas in the hepatic portal vein (HPVG), were handled in 2 distinct ways: surgically and conservatively. One needed diagnostic laparoscopy with necrotic segmentectomy and was discharged from the hospital on postoperative day 16. The last patient, received resuscitation treatment due to severe comorbidities and inability to tolerate surgery. After 3 days, abdominal CT scan revealed no signs of remaining PI. However, the patient was terminally discharged after 7 weeks of treatment due to septic shock caused by sacrococcygeal ulcer and urinary tract infection. By drawing comparisons among these 3 scenarios, we aim to highlight certain indicators for conservative treatment success. CONCLUSIONS PI with HPVG is a sign of severe prognosis, which often requires surgical intervention. However, the decision to manage conservatively or surgically depends on the patient's condition and other criteria such as peritonitis, free fluid in the abdominal cavity, and the presence of shock. Physicians should also weigh the benefits and risks of surgical intervention in critically ill patients.


Assuntos
Cavidade Abdominal , Laparoscopia , Masculino , Humanos , Veia Porta , Necrose , Tomografia Computadorizada por Raios X/métodos
5.
JMIR Form Res ; 8: e52462, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517457

RESUMO

BACKGROUND: In this paper, we present an automated method for article classification, leveraging the power of large language models (LLMs). OBJECTIVE: The aim of this study is to evaluate the applicability of various LLMs based on textual content of scientific ophthalmology papers. METHODS: We developed a model based on natural language processing techniques, including advanced LLMs, to process and analyze the textual content of scientific papers. Specifically, we used zero-shot learning LLMs and compared Bidirectional and Auto-Regressive Transformers (BART) and its variants with Bidirectional Encoder Representations from Transformers (BERT) and its variants, such as distilBERT, SciBERT, PubmedBERT, and BioBERT. To evaluate the LLMs, we compiled a data set (retinal diseases [RenD] ) of 1000 ocular disease-related articles, which were expertly annotated by a panel of 6 specialists into 19 distinct categories. In addition to the classification of articles, we also performed analysis on different classified groups to find the patterns and trends in the field. RESULTS: The classification results demonstrate the effectiveness of LLMs in categorizing a large number of ophthalmology papers without human intervention. The model achieved a mean accuracy of 0.86 and a mean F1-score of 0.85 based on the RenD data set. CONCLUSIONS: The proposed framework achieves notable improvements in both accuracy and efficiency. Its application in the domain of ophthalmology showcases its potential for knowledge organization and retrieval. We performed a trend analysis that enables researchers and clinicians to easily categorize and retrieve relevant papers, saving time and effort in literature review and information gathering as well as identification of emerging scientific trends within different disciplines. Moreover, the extendibility of the model to other scientific fields broadens its impact in facilitating research and trend analysis across diverse disciplines.

6.
Cureus ; 15(4): e37228, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37168180

RESUMO

Orbital lymphoma is a rare tumor with an incidence of 2.02 per million per year. It can occur as a part of systemic lymphoma or spontaneously arise primarily in orbit. The most commonly reported malignant lymphoma is non-Hodgkin's lymphoma. The typical clinical finding includes exophthalmos, swelling, and limited eye movement. Our patient presented with dryness and irritation of the eye without signs of proptosis until months later. The definitive diagnosis of orbital lymphoma requires a biopsy. Still, imaging studies such as MRI and CT scans play a critical role in distinguishing benign from malignant lesions and invasion of local tissues. The treatment of orbital lymphoma is multidisciplinary, involving surgical resection, radiotherapy, and chemotherapy depending on the histological type of tumor and the presence of metastasis.

7.
Acta Psychol (Amst) ; 241: 104096, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38041914

RESUMO

Managers have been applying the influence of herd behaviour to stimulate purchase intention but have not achieved precise results because they do not clearly understand the mechanism of this relationship. This article aims to determine the effect of herd behaviour on the relationship between information adoption and purchase intention and the moderating of risk aversion. With 17 variables for four concepts, data was collected online with 340 respondents and analysed with a partial least squares structural equation modelling. When considering herd behaviour in terms of subjective norms with corroborated information, this study upgrades the classic role of the theory of planned behaviour in purchase intention. The findings indicate a positive relationship between herd behaviour, information adoption and purchase intention. In particular, risk aversion is a positive moderator of the relationship between herd behaviour and purchase intention. This result is a significant addition to the theoretical body and shows that risk aversion can drive purchase intention through herd behaviour. In other words, this study upgrades the perception of information source authentication through herd behaviour to explain the purchase intentions of Vietnamese consumers. These results show that managers can create risky situations to promote herd behaviour. They can also apply information adoption stimuli to stimulate herd behaviour. At the same time, through the information adoption mechanism, consumers can be more alert to the effect of herd behaviour and have more opinions when making purchases.


Assuntos
Atitude , Intenção , Humanos , Vietnã , Comportamento do Consumidor
8.
Dev Cell ; 57(15): 1817-1832.e5, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35835116

RESUMO

Stochastic mechanisms diversify cell fates during development. How cells randomly choose between two or more fates remains poorly understood. In the Drosophila eye, the random mosaic of two R7 photoreceptor subtypes is determined by expression of the transcription factor Spineless (Ss). We investigated how cis-regulatory elements and trans factors regulate nascent transcriptional activity and chromatin compaction at the ss gene locus during R7 development. The ss locus is in a compact state in undifferentiated cells. An early enhancer drives transcription in all R7 precursors, and the locus opens. In differentiating cells, transcription ceases and the ss locus stochastically remains open or compacts. In SsON R7s, ss is open and competent for activation by a late enhancer, whereas in SsOFF R7s, ss is compact, and repression prevents expression. Our results suggest that a temporally dynamic antagonism, in which transcription drives large-scale decompaction and then compaction represses transcription, controls stochastic fate specification.


Assuntos
Proteínas de Drosophila , Células Fotorreceptoras de Invertebrados , Animais , Cromatina/genética , Cromatina/metabolismo , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Células Fotorreceptoras de Invertebrados/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
PeerJ ; 9: e11671, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34277149

RESUMO

BACKGROUND: By comparing spatial geographical structures of host populations with that of their symbionts light can be shed on their biological interactions, and the degree of congruence between host and symbiont phylogeographies should reflect their life histories and especially dispersal mechanisms. METHODS: Here, we analyzed the genetic diversity and structure of a host, the blue swimming crab, Portunus pelagicus, and its symbiotic pedunculate barnacle Octolasmis angulata from six location sites representing three geographic regions (north, central and south) along the Vietnam coastline. High levels of congruence in their phylogeographic patterns were expected as they both undergo planktonic larval stages. RESULTS: Based on the COI mtDNA markers, O. angulata populations showed higher genetic diversity in comparison with their host P. pelagicus (number of haplotype/individuals, haplotype and nucleotide diversity are 119/192, 0.991 ± 0.002 and 0.02; and 89/160, 0.913 ± 0.02 and 0.015, respectively). Pairwise Fst and AMOVA analyses showed a more pronounced population structure in the symbiotic barnacle than in its crab host. The DAPC analyses identified three genetic clusters. However, both haplotype networks and scatter plots supported connectivity of the host and the symbiotic barnacle throughout their distribution range, except for low subdivision of southern population. Isolation by distance were detected only for the symbiont O. angulata (R2 = 0.332, P = 0.05), while dbMEM supported spatial structure of both partners, but only at MEM-1 (Obs. 0.2686, P < 0.01 and Obs. 0.2096, P < 0.01, respectively).

10.
PLoS One ; 14(11): e0224473, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31689298

RESUMO

The blue swimming crab (Portunus pelagicus Linnaeus, 1758) is one of the commercially exploited crab fishery resources in Vietnam. This is the first study to provide a broad survey of genetic diversity, population structure and migration patterns of P. pelagicus along the Vietnamese coastline. The crab samples were collected from northern, central and southern Vietnam. Here, we used a panel of single nucleotide polymorphisms (SNPs) generated from restriction site-associated DNA sequencing (RADseq). After removing 32 outlier loci, 306 putatively neutral SNPs from 96 individuals were used to assess fine-scale population structure of blue swimming crab. The mean observed heterozygosity (Ho) and expected heterozygosity (He) per locus was 0.196 and 0.223, respectively. Pairwise Fst and hierarchical AMOVA supported significant differentiation of central and northern from southern populations (P<0.01). Population structure analyses revealed that P. pelagicus in the south is a separate fisheries unit from the north and center. Contemporary migration patterns supported high migration between northern and central populations and restricted genetic exchange within the southern population. In contrast, historic gene flow provides strong evidence for single panmictic population. The results are useful for understanding current status of P. pelagicus in the wild under an environment changing due to natural and anthropogenic stresses, with implications for fisheries management.


Assuntos
Braquiúros/genética , Pesqueiros/estatística & dados numéricos , Fluxo Gênico , Animais , Feminino , Masculino , Polimorfismo de Nucleotídeo Único , Dinâmica Populacional/estatística & dados numéricos , Análise de Sequência de DNA , Vietnã
11.
Dev Cell ; 51(3): 341-356.e7, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31607649

RESUMO

Homologous chromosomes colocalize to regulate gene expression in processes including genomic imprinting, X-inactivation, and transvection. In Drosophila, homologous chromosomes pair throughout development, promoting transvection. The "button" model of pairing proposes that specific regions along chromosomes pair with high affinity. Here, we identify buttons interspersed across the fly genome that pair with their homologous sequences, even when relocated to multiple positions in the genome. A majority of transgenes that span a full topologically associating domain (TAD) function as buttons, but not all buttons contain TADs. Additionally, buttons are enriched for insulator protein clusters. Fragments of buttons do not pair, suggesting that combinations of elements within a button are required for pairing. Pairing is necessary but not sufficient for transvection. Additionally, pairing and transvection are stronger in some cell types than in others, suggesting that pairing strength regulates transvection efficiency between cell types. Thus, buttons pair homologous chromosomes to facilitate cell-type-specific interchromosomal gene regulation.


Assuntos
Pareamento Cromossômico/genética , Cromossomos/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica , Loci Gênicos , Animais , Cromatina/metabolismo , Elementos Isolantes/genética , Transgenes
12.
J Immigr Minor Health ; 17(1): 298-301, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24715472

RESUMO

Few studies have investigated the prevalence of hepatitis B virus (HBV) and C virus (HCV) infection among Vietnamese Americans (VAs). The purpose of this paper is to assess the prevalence of HBV and HCV infection, identify the sociodemographic characteristics of the HBV infected population and the level of HBV knowledge among VAs in the Baltimore-Washington metropolitan areas with data from a health fair in 2011. A total of 617 VAs received serological testing for HBV and HCV, and 329 completed a survey of HBV knowledge assessment. About 9% were infected with HBV and 5% with HCV. Vietnamese Americans younger than 30 years had the highest HBV prevalence (13.1%) followed by those age 41-50 years (12.1%). The prevalence of HCV infection was particularly higher among those older than 70 years old (13.9%). Misunderstanding HBV as a food-borne disease is prevalent among VAs. Efforts to develop public health screening and education programs targeting this population are warranted.


Assuntos
Asiático/estatística & dados numéricos , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Programas de Rastreamento , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Vietnã/etnologia
13.
PLoS One ; 7(9): e45553, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23029091

RESUMO

A total of 221 isolates of M. tuberculosis were sampled from hospitals and the general population in the northern plain of Vietnam, one of the most populated region of the country. Genotypic composition and diversity were characterized, and we investigated how they are affected by sampling (hospital vs. general population), correcting for potential confounding effects (location, age and gender of the patients). Spoligotyping and 12 MIRU-VNTR typing were used as first line. Then 15 MIRU-VNTR standard set was used, making 21 MIRU-VNTR typing for the clustered isolates. Result showed that 8 lineages and 13 sub-lineages were circulating in the region. The most predominant lineages were Beijing (38.5%) and EAI (38.5%). Others appeared with small proportions H (1.4%), LAM (1.8%), T (8.1%), X (0.9%), MANU (2.3%), and Zero (0.4%). Higher clustering rate was found in the hospital samples (17.9% in urban and 19.2% in rural areas) compared to the population ones (0%). The typical Vietnamese EAI4-VNM sub-lineage of EAI lineage accounted for 67% of EAI strains and was associated with older ages. Beijing genotypes were associated with younger, urban population and were characterized by high clustering rates. These characteristics strongly suggest that Beijing strains are invading the population, replacing the local EAI-VNM4, thus predicting a more serious tuberculosis situation in the future in the absence of more effective control strategies.


Assuntos
Genótipo , Mycobacterium tuberculosis/genética , Tuberculose/epidemiologia , DNA Bacteriano , Feminino , Variação Genética , Humanos , Masculino , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Prevalência , População Rural , População Urbana , Vietnã/epidemiologia
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