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1.
Proc Natl Acad Sci U S A ; 120(43): e2308658120, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37844234

RESUMO

Dysregulated apoptosis and proliferation are fundamental properties of cancer, and microRNAs (miRNA) are critical regulators of these processes. Loss of miR-15a/16-1 at chromosome 13q14 is the most common genomic aberration in chronic lymphocytic leukemia (CLL). Correspondingly, the deletion of either murine miR-15a/16-1 or miR-15b/16-2 locus in mice is linked to B cell lymphoproliferative malignancies. However, unexpectedly, when both miR-15/16 clusters are eliminated, most double knockout (DKO) mice develop acute myeloid leukemia (AML). Moreover, in patients with CLL, significantly reduced expression of miR-15a, miR-15b, and miR-16 associates with progression of myelodysplastic syndrome to AML, as well as blast crisis in chronic myeloid leukemia. Thus, the miR-15/16 clusters have a biological relevance for myeloid neoplasms. Here, we demonstrate that the myeloproliferative phenotype in DKO mice correlates with an increase of hematopoietic stem and progenitor cells (HSPC) early in life. Using single-cell transcriptomic analyses, we presented the molecular underpinning of increased myeloid output in the HSPC of DKO mice with gene signatures suggestive of dysregulated hematopoiesis, metabolic activities, and cell cycle stages. Functionally, we found that multipotent progenitors (MPP) of DKO mice have increased self-renewing capacities and give rise to significantly more progeny in the granulocytic compartment. Moreover, a unique transcriptomic signature of DKO MPP correlates with poor outcome in patients with AML. Together, these data point to a unique regulatory role for miR-15/16 during the early stages of hematopoiesis and to a potentially useful biomarker for the pathogenesis of myeloid neoplasms.


Assuntos
Leucemia Linfocítica Crônica de Células B , Leucemia Mieloide Aguda , MicroRNAs , Transtornos Mieloproliferativos , Humanos , Animais , Camundongos , Leucemia Linfocítica Crônica de Células B/genética , MicroRNAs/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Divisão Celular , Transtornos Mieloproliferativos/genética
2.
Heliyon ; 10(8): e28371, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38655330

RESUMO

Background: Standardized and validated heat inactivation procedure for Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are not available. For heat inactivation, various protocols were reported to prepare External Quality Assessment Programme (EQAP) samples without direct comparison between different durations. Objective: To assess the heat inactivation procedures against SARS-CoV-2. The efficacy of the optimized condition was reflected by the results from laboratories testing the EQAP samples. Study design: The SARS-CoV-2 strain was exposed to 95 °C in a water bath for three different time intervals, 5 min, 10 min and 15 min, respectively. The efficacy of inactivation was confirmed by the absence of cytopathic effects and decreasing viral load in 3 successive cell line passages. The viral stock inactivated by the optimal time interval was dispatched to EQAP participants and the result returned were analyzed. Results: All of the three conditions were capable of inactivating the SARS-CoV-2 of viral load at around cycle threshold value of 10. When the 95 °C 10 min condition was chosen to prepare SARS-CoV-2 EQAP samples, they showed sufficient homogeneity and stability. High degree of consensus was observed among EQAP participants in all samples dispatched. Conclusions: The conditions evaluated in the present study could be helpful for laboratories in preparing SARS-CoV-2 EQAP samples.

3.
Cell Stem Cell ; 31(3): 378-397.e12, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38402617

RESUMO

Mechanisms governing the maintenance of blood-producing hematopoietic stem and multipotent progenitor cells (HSPCs) are incompletely understood, particularly those regulating fate, ensuring long-term maintenance, and preventing aging-associated stem cell dysfunction. We uncovered a role for transitory free cytoplasmic iron as a rheostat for adult stem cell fate control. We found that HSPCs harbor comparatively small amounts of free iron and show the activation of a conserved molecular response to limited iron-particularly during mitosis. To study the functional and molecular consequences of iron restriction, we developed models allowing for transient iron bioavailability limitation and combined single-molecule RNA quantification, metabolomics, and single-cell transcriptomic analyses with functional studies. Our data reveal that the activation of the limited iron response triggers coordinated metabolic and epigenetic events, establishing stemness-conferring gene regulation. Notably, we find that aging-associated cytoplasmic iron loading reversibly attenuates iron-dependent cell fate control, explicating intervention strategies for dysfunctional aged stem cells.


Assuntos
Hematopoese , Ferro , Hematopoese/genética , Ferro/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Multipotentes/metabolismo , Regulação da Expressão Gênica , Diferenciação Celular
4.
Cancers (Basel) ; 15(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37835400

RESUMO

Chronic lymphocytic leukemia (CLL) clones contain subpopulations differing in time since the last cell division ("age"): recently born, proliferative (PF; CXCR4DimCD5Bright), intermediate (IF; CXCR4IntCD5Int), and resting (RF; CXCR4BrightCD5Dim) fractions. Herein, we used deuterium (2H) incorporation into newly synthesized DNA in patients to refine the kinetics of CLL subpopulations by characterizing two additional CXCR4/CD5 fractions, i.e., double dim (DDF; CXCR4DimCD5Dim) and double bright (DBF; CXCR4BrightCD5Bright); and intraclonal fractions differing in surface membrane (sm) IgM and IgD densities. Although DDF was enriched in recently divided cells and DBF in older cells, PF and RF remained the most enriched in youngest and oldest cells, respectively. Similarly, smIgMHigh and smIgDHigh cells were the youngest, and smIgMLow and smIgDLow were the oldest, when using smIG levels as discriminator. Surprisingly, the cells closest to the last stimulatory event bore high levels of smIG, and stimulating via TLR9 and smIG yielded a phenotype more consistent with the in vivo setting. Finally, older cells were less sensitive to in vivo inhibition by ibrutinib. Collectively, these data define additional intraclonal subpopulations with divergent ages and phenotypes and suggest that BCR engagement alone is not responsible for the smIG levels found in vivo, and the differential sensitivity of distinct fractions to ibrutinib might account, in part, for therapeutic relapse.

5.
Front Oncol ; 13: 1112879, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007084

RESUMO

Introduction: The leukemic cells of patients with chronic lymphocytic leukemia (CLL) are often unique, expressing remarkably similar IGHV-IGHD-IGHJ gene rearrangements, "stereotyped BCRs". The B-cell receptors (BCRs) on CLL cells are also distinctive in often deriving from autoreactive B lymphocytes, leading to the assumption of a defect in immune tolerance. Results: Using bulk and single-cell immunoglobulin heavy and light chain variable domain sequencing, we enumerated CLL stereotype-like IGHV-IGHD-IGHJ sequences (CLL-SLS) in B cells from cord blood (CB) and adult peripheral blood (PBMC) and bone marrow (BM of healthy donors. CLL-SLS were found at similar frequencies among CB, BM, and PBMC, suggesting that age does not influence CLL-SLS levels. Moreover, the frequencies of CLL-SLS did not differ among B lymphocytes in the BM at early stages of development, and only re-circulating marginal zone B cells contained significantly higher CLL-SLS frequencies than other mature B-cell subpopulations. Although we identified CLL-SLS corresponding to most of the CLL major stereotyped subsets, CLL-SLS frequencies did not correlate with those found in patients. Interestingly, in CB samples, half of the CLL-SLS identified were attributed to two IGHV-mutated subsets. We also found satellite CLL-SLS among the same normal samples, and they were also enriched in naïve B cells but unexpectedly, these were ~10-fold higher than standard CLL-SLS. In general, IGHV-mutated CLL-SLS subsets were enriched among antigen-experienced B-cell subpopulations, and IGHV-unmutated CLL-SLS were found mostly in antigen-inexperienced B cells. Nevertheless, CLL-SLS with an IGHV-mutation status matching that of CLL clones varied among the normal B-cell subpopulations, suggesting that specific CLL-SLS could originate from distinct subpopulations of normal B cells. Lastly, using single-cell DNA sequencing, we identified paired IGH and IGL rearrangements in normal B lymphocytes resembling those of stereotyped BCRs in CLL, although some differed from those in patients based on IG isotype or somatic mutation. Discussion: CLL-SLS are present in normal B-lymphocyte populations at all stages of development. Thus, despite their autoreactive profile they are not deleted by central tolerance mechanisms, possibly because the level of autoreactivity is not registered as dangerous by deletion mechanisms or because editing of L-chain variable genes occurred which our experimental approach could not identify.

6.
J Virol Methods ; 300: 114396, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34856306

RESUMO

BACKGROUND: Combined nasal-and-throat swabs (CNTS) is less invasive and easy to execute. CNTS also induces lower risk to healthcare workers upon collection. However, there is a lack of data on viral load assessment for population-wide testing. OBJECTIVE: This study assessed if CNTS is suitable as an alternative specimen type for the detection of SARS-CoV-2. METHODS: We assessed the viral load of SARS-CoV-2 in CNTS collected from COVID-19 individuals through the 2-week period of the Universal Community Testing Programme (UCTP) conducted in Hong Kong. In addition, we compared viral loads of SARS-CoV-2 for the paired CNTS and non-CNTS specimens among these individuals. RESULTS: This UCTP identified 48 COVID-19 individuals from nearly 2 million specimens collected. The viral loads of SARS-CoV-2 varied widely, cycle threshold values Ct 16.28-36.94, among symptoms and asymptomatic individuals. The viral loads for the paired CNTS and non-CNTS specimens were comparable. CONCLUSIONS: This study demonstrated that CNTS could be a specimen of choice for diagnosis of SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Hong Kong , Humanos , Nasofaringe , Faringe , Manejo de Espécimes , Carga Viral
7.
JCI Insight ; 7(12)2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35511436

RESUMO

Chronic lymphocytic leukemia (CLL) results from expansion of a CD5+ B cell clone that requires interactions with other cell types, including T cells. Moreover, patients with CLL have elevated levels of circulating IL-17A+ and IL-17F+ CD4+ T (Th17) cells, with higher numbers of IL-17A+ Th17 cells correlating with better outcomes. We report that CLL Th17 cells expressed more miR155, a Th17-differentiation regulator, than control Th17 cells, despite naive CD4+ T (Tn) cell basal miR155 levels being similar in both. We also found that CLL cells directly regulated miR155 levels in Tn cells, thereby affecting Th17 differentiation, by documenting that coculturing Tn cells with resting or activated (Bact) CLL cells altered the magnitude and direction of T cell miR155 levels; CLL Bact cells promoted IL-17A+ and IL-17F+ T cell generation by an miR155-dependent mechanism, confirmed by miR155 inhibition; coculture of Tn cells with CLL Bact cells led to a linear correlation between the degree and direction of T cell miR155 expression changes and production of IL-17F but not IL-17A; and Bact cell-mediated changes in Tn cell miR155 expression correlated with outcome, irrespective of IGHV mutation status, a strong prognostic indicator. These results identify a potentially unrecognized CLL Bact cell-dependent mechanism, upregulation of Tn cell miR155 expression and subsequent enhancement of IL-17F+ Th17 generation, that favors better clinical courses.


Assuntos
Leucemia Linfocítica Crônica de Células B , MicroRNAs , Células Th17 , Humanos , Interleucina-17/metabolismo , Leucemia Linfocítica Crônica de Células B/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Células Th17/metabolismo
8.
J Med Virol ; 83(3): 483-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21264869

RESUMO

Enterovirus (EV) infection is a common disease of childhood and associated not uncommonly with aseptic meningitis. In the summer of 2008, laboratory surveillance has detected increased number of coxsackievirus B3 (CVB3) associated aseptic meningitis in Hong Kong, constituting 11.6% of those infected. This study analyzed the epidemiology, circulating pattern, and clinical presentations of CVB3 in Hong Kong over the last 10 years with reference to the circulation of EV in the locality. Enteroviruses (EV) were isolated from respiratory, cerebrospinal fluid (CSF), stool, and vesicular samples using human rhabdomyosarcoma, human laryngeal carcinoma (HEp2-C), human lung fibroblast (MRC-5), and African green monkey kidney (Vero) cell lines. Virus isolates were identified and characterized by indirect immunofluorescence (IF) using monoclonal antibodies (mAB), neutralization test as well as partial VP1 sequencing. Different from previous years, IF test result showed that majority of the isolates from 2008 were untypeable by the mAB suggesting antigenic change. Sequence analysis revealed that these isolates were clustered with recent isolate from Fuyang, China. Review of data from 1999 to 2008 showed increased activity of CVB3 in the years 2005 and 2008, and isolates in these 2 years displayed an amino acid change from threonine to alanine at codon 277 of the VP1 gene, which may be associated with central nervous system (CNS) disease.


Assuntos
Doenças Transmissíveis Emergentes , Infecções por Coxsackievirus/epidemiologia , Infecções por Coxsackievirus/virologia , Enterovirus Humano B , Meningite Asséptica/epidemiologia , Meningite Asséptica/virologia , Animais , Proteínas do Capsídeo/genética , China , Chlorocebus aethiops , Enterovirus Humano B/classificação , Enterovirus Humano B/genética , Enterovirus Humano B/imunologia , Enterovirus Humano B/isolamento & purificação , Hong Kong , Humanos , Dados de Sequência Molecular , Tipagem Molecular , Testes de Neutralização , Filogenia , Células Vero
9.
Hematol Oncol Clin North Am ; 35(4): 665-685, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34174979

RESUMO

Chronic lymphocytic leukemia (CLL) is a common, incurable disease of undefined cause. Notably, the normal cell equivalents of CLL cells remain elusive, and it is possible that the disease emanates from several normal B-cell subsets. This article reviews the literature relating to this issue, focusing on recent findings, in particular made through epigenetic analyses that strongly support the disease developing from a normal Ag-experienced and memory cell-like B lymphocyte. It also reports the known pathways whereby normal B lymphocytes mature after antigenic challenge and proposes that this information is relevant in defining the cells of origin of this disease.


Assuntos
Linfócitos B , Leucemia Linfocítica Crônica de Células B , Linfócitos B/citologia , Humanos , Leucemia Linfocítica Crônica de Células B/genética
10.
Cancer Prev Res (Phila) ; 14(4): 441-454, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33419763

RESUMO

We investigated a Spanish and Catalan family in which multiple cancer types tracked across three generations, but for which no genetic etiology had been identified. Whole-exome sequencing of germline DNA from multiple affected family members was performed to identify candidate variants to explain this occurrence of familial cancer. We discovered in all cancer-affected family members a single rare heterozygous germline variant (I654V, rs1801201) in ERBB2/HER2, which is located in a transmembrane glycine zipper motif critical for ERBB2-mediated signaling and in complete linkage disequilibrium (D' = 1) with a common polymorphism (I655V, rs1136201) previously reported in some populations as associated with cancer risk. Because multiple cancer types occurred in this family, we tested both the I654V and the I655V variants for association with cancer across multiple tumor types in 6,371 cases of Northern European ancestry drawn from The Cancer Genome Atlas and 6,647 controls, and found that the rare variant (I654V) was significantly associated with an increased risk for cancer (OR = 1.40; P = 0.021; 95% confidence interval (CI), 1.05-1.89). Functional assays performed in HEK 293T cells revealed that both the I655V single mutant (SM) and the I654V;I655V double mutant (DM) stabilized ERBB2 protein and activated ERBB2 signaling, with the DM activating ERBB2 significantly more than the SM alone. Thus, our results suggest a model whereby heritable genetic variation in the transmembrane domain activating ERBB2 signaling is associated with both sporadic and familial cancer risk, with increased ERBB2 stabilization and activation associated with increased cancer risk. PREVENTION RELEVANCE: By performing whole-exome sequencing on germline DNA from multiple cancer-affected individuals belonging to a family in which multiple cancer types track across three generations, we identified and then characterized functional common and rare variation in ERBB2 associated with both sporadic and familial cancer. Our results suggest that heritable variation activating ERBB2 signaling is associated with risk for multiple cancer types, with increases in signaling correlated with increases in risk, and modified by ancestry or family history.


Assuntos
Biomarcadores Tumorais/genética , Exoma , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Síndromes Neoplásicas Hereditárias/patologia , Receptor ErbB-2/genética , Adolescente , Adulto , Idoso , Criança , Análise Mutacional de DNA , Feminino , Testes Genéticos , Humanos , Masculino , Síndromes Neoplásicas Hereditárias/genética , Linhagem , Sequenciamento do Exoma , Adulto Jovem
11.
Emerg Infect Dis ; 15(6): 966-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19523305

RESUMO

Surveillance of amantadine and oseltamivir resistance among influenza viruses was begun in Hong Kong in 2006. In 2008, while both A/Brisbane/59/2007-like and A/Hong Kong/2652/2006-like viruses (H1N1) were cocirculating, we detected amantadine and oseltamivir resistance among A/Hong Kong/2652/2006-like viruses (H1N1), caused by genetic reassortment or spontaneous mutation.


Assuntos
Amantadina/farmacologia , Antivirais/farmacologia , Farmacorresistência Viral/genética , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Influenza Humana/virologia , Oseltamivir/farmacologia , Linhagem Celular , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Hong Kong , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase/métodos , Vigilância da População , Análise de Sequência de DNA
12.
Lab Chip ; 18(18): 2776-2786, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30090895

RESUMO

Tissues are increasingly being analyzed at the single cell level in order to characterize cellular diversity and identify rare cell types. Single cell analysis efforts are greatly limited, however, by the need to first break down tissues into single cell suspensions. Current dissociation methods are inefficient, leaving a significant portion of the tissue as aggregates that are filtered away or left to confound results. Here, we present a simple and inexpensive microfluidic device that simultaneously filters large tissue fragments and dissociates smaller aggregates into single cells, thereby improving single cell yield and purity. The device incorporates two nylon mesh membranes with well-defined, micron-sized pores that operate on aggregates of different size scales. We also designed the device so that the first filtration could be performed under tangential flow to minimize clogging. Using cancer cell lines, we demonstrated that aggregates were effectively dissociated using high flow rates and pore sizes that were smaller than a single cell. However, pore sizes that were less than half the cell size caused significant damage. We then improved results by passing the sample through two filter devices in series, with single cell yield and purity predominantly determined by the pore size of the second membrane. Next, we optimized performance using minced and digested murine kidney tissue samples, and determined that the combination of 50 and 15 µm membranes was optimal. Finally, we integrated these two membranes into a single filter device and performed validation experiments using minced and digested murine kidney, liver, and mammary tumor tissue samples. The dual membrane microfluidic filter device increased single cell numbers by at least 3-fold for each tissue type, and in some cases by more than 10-fold. These results were obtained in minutes without affecting cell viability, and additional filtering would not be required prior to downstream applications. In future work, we will create complete tissue analysis platforms by integrating the dual membrane microfluidic filter device with additional upstream tissue processing technologies, as well as downstream operations such as cell sorting and detection.


Assuntos
Agregação Celular , Separação Celular/instrumentação , Filtração/instrumentação , Dispositivos Lab-On-A-Chip , Membranas Artificiais , Nylons , Animais , Humanos , Rim/citologia , Células MCF-7 , Camundongos , Análise de Célula Única
13.
Perit Dial Int ; 36(5): 526-32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27282852

RESUMO

UNLABELLED: ♦ BACKGROUND AND OBJECTIVE: Residual renal function (RRF) correlates with mortality and morbidity rates in patients receiving peritoneal dialysis (PD). We examined the effect of a biocompatible PD solution (Gambrosol Trio; Gambro Lundia AB, Lund, Sweden) with lower concentrations of glucose degradation products on rates of decline in RRF. ♦ DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Incident patients at 2 centers in Canada and 1 in Hong Kong were randomized (by minimization) in an open-label parallel group trial to receive Gambrosol Trio or standard PD solution (Dianeal; Baxter Healthcare, Mississauga, Canada) for 2 years. Primary outcome was slope of RRF. Secondary outcomes were urine volumes, fluid and nutrition indices, PD and membrane characteristics, peritonitis rates, adverse events, and PD technique survival. ♦ RESULTS: Residual renal function declined by 0.132 mL/minute/1.73 m(2)/month in 51 patients allocated to biocompatible, and 0.174 mL/minute/1.73 m(2)/month in 50 patients allocated to standard PD solution (difference 0.042 mL/minute/1.73 m(2)/month, p = 0.001). Urine volume, body mass index, normalized protein catabolic rates, and fat mass were higher; total body water, peritoneal ultrafiltration, and D/P creatinine did not differ; and serum phosphate, rates of icodextrin, and automated cycler use were lower with Gambrosol Trio use. There were more peritonitis events with Gambrosol Trio use, while PD technique survival did not differ between groups. ♦ CONCLUSIONS: The use of the biocompatible PD solution Gambrosol Trio was associated with slower rates of decline in RRF, fluid and nutrition benefits, and increased peritonitis rates. TRIAL NUMBER: ISRCTN26252543.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Soluções para Diálise/química , Taxa de Filtração Glomerular/fisiologia , Diálise Peritoneal/métodos , Peritonite/prevenção & controle , Idoso , Canadá , Soluções para Diálise/efeitos adversos , Feminino , Seguimentos , Hong Kong , Humanos , Estimativa de Kaplan-Meier , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/terapia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal/efeitos adversos , Peritonite/etiologia , Modelos de Riscos Proporcionais , Medição de Risco , Estatísticas não Paramétricas , Resultado do Tratamento
14.
J Cataract Refract Surg ; 28(7): 1217-22, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12106731

RESUMO

PURPOSE: To evaluate the outcomes of intraocular lens (IOL) exchange in patients with calcified hydrogel IOLs. SETTING: Ophthalmology departments of 2 university hospitals in Hong Kong, China. METHODS: Fifteen patients developed loss of vision resulting from calcification of hydrogel IOLs. The calcified IOLs were explanted and replaced with new IOLs. The best corrected visual acuity before and after surgery was measured and compared. RESULTS: The mean visual acuity was 0.03 (range 0.01 to 0.20) before IOL exchange and 0.20 (range 0.01 to 0.50) 3 months after; the difference was significant (P <.001). Acuity improved approximately 5 Snellen lines. Complications included posterior capsule rupture in 2 patients and zonular dehiscence in 3 patients; the secondary IOL was placed in the anterior chamber or ciliary sulcus in these patients. Three patients required cutting of the haptics before the calcified IOL could be removed. CONCLUSION: Intraocular lens exchange was an effective treatment in patients with calcified hydrogel IOLs.


Assuntos
Calcinose/cirurgia , Complicações Intraoperatórias , Lentes Intraoculares , Complicações Pós-Operatórias , Falha de Prótese , Transtornos da Visão/cirurgia , Idoso , Idoso de 80 Anos ou mais , Calcinose/complicações , Remoção de Dispositivo , Feminino , Humanos , Implante de Lente Intraocular/efeitos adversos , Masculino , Pessoa de Meia-Idade , Reoperação , Transtornos da Visão/etiologia , Acuidade Visual
16.
Am J Ophthalmol ; 153(4): 627-31, 631.e1-3, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22105798

RESUMO

PURPOSE: To compare pain scores with and without supplementary topical 2% lidocaine gel in patients undergoing simultaneous bilateral laser-assisted in situ keratomileusis (LASIK) under topical anesthesia using 0.5% proparacaine eye drops. DESIGN: Randomized double-masked placebo-controlled trial. METHODS: Fifty-one Chinese subjects (102 eyes, with 51 eyes in each arm) were included. One eye was randomly allocated to have supplementary 2% lidocaine gel while the other eye received carbomer gel as control, in addition to topical 0.5% proparacaine. The pain scores for each eye during microkeratome flap creation, during laser ablation, and at 15, 30, and 45 minutes after LASIK were assessed. An overall pain score of the LASIK procedure was also obtained. Primary outcome measures were pain scores during and after LASIK. Secondary outcomes included need for additional topical anesthesia, patient cooperation score, and duration and complications of surgery. RESULTS: In the 2% lidocaine gel-treated group, the pain scores were significantly lower during microkeratome flap creation and laser ablation, and postoperatively at 30 and 45 minutes (P<.05 for all). Patients in the lidocaine gel group required less additional topical anesthesia (P=.0004) and were more cooperative (P=.019) as compared to the carbomer gel group. No surgical or postoperative complications were observed. CONCLUSIONS: The use of supplementary 2% lidocaine gel in LASIK is effective in lowering the pain experienced during and up to 45 minutes after LASIK.


Assuntos
Anestésicos Locais/administração & dosagem , Dor Ocular/diagnóstico , Ceratomileuse Assistida por Excimer Laser In Situ , Lasers de Excimer/uso terapêutico , Lidocaína/administração & dosagem , Dor Pós-Operatória/diagnóstico , Adulto , Anestesia Local/métodos , Método Duplo-Cego , Feminino , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Propoxicaína/administração & dosagem , Adulto Jovem
17.
J Clin Virol ; 47(2): 182-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20022296

RESUMO

BACKGROUND: To diagnose influenza A(H1N1)v virus infection, accurate and rapid detection are important. However, there is scanty data on the performance of various laboratory diagnostics. OBJECTIVE: To compare the performance of rapid antigen test (RAT), viral culture and RT-PCR for the detection of influenza A(H1N1)v virus and to correlate their performance with the time after symptom onset and viral load. STUDY DESIGN: From May 1, 2009 to June 25, 2009, respiratory samples were collected from 5740 individuals suspected of having influenza A(H1N1)v infection. The performance of viral culture and RT-PCR were investigated and correlated with the time after symptom onset. The sensitivity of RAT ESPLINE influenza A & B-N (Fujirebio Inc, Tokyo) was evaluated using a subset of 60 samples from patients diagnosed as having influenza A(H1N1)v infection. RESULTS: Using respiratory samples from 587 patients diagnosed with influenza A(H1N1)v infection, comparison of laboratory diagnostics showed viral culture and RT-PCR gave comparable results with overall sensitivity of 93.9% and 98.1%, respectively. For RAT, when testing a subset of 60 samples collected < or =3 days following symptom onset, the sensitivity was 62%. CONCLUSIONS: Although viral shedding is prolonged and of higher titre in influenza A(H1N1)v infection, RAT showed a low sensitivity of 62% among patients presenting < or =3 days after symptom onset. Viral culture showed comparable performance with RT-PCR and with sensitivity better than that documented for seasonal influenza.


Assuntos
Técnicas de Laboratório Clínico/métodos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/virologia , Carga Viral , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Humanos , Imunoensaio/métodos , Lactente , Influenza Humana/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade , Fatores de Tempo , Cultura de Vírus/métodos , Adulto Jovem
19.
Eye Contact Lens ; 34(2): 113-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18327048

RESUMO

PURPOSE: To describe the clinical features and outcomes among contact lens wearers with Fusarium keratitis. METHODS: A retrospective observational review of all cases of culture-proven Fusarium keratitis among contact lens wearers from three hospitals in Hong Kong Island were included. The clinical features, hygiene habits, and clinical outcomes were reviewed. RESULTS: Sixteen patients (17 eyes) were diagnosed with Fusarium keratitis associated with contact lens wear. One patient had bilateral involvement. Six patients had a central lesion; four had paraxial lesions; one had paraxial and peripheral lesions; and the rest had peripheral lesions. Ten (62.5%) patients reported using ReNu multipurpose cleaning solution. Most patients had poor contact lens hygiene habits. One patient required systemic antifungal treatment. No surgical intervention was required in any of the patients. CONCLUSIONS: The clinical features of Fusarium keratitis in contact lens wearers can be variable. Although fungal infection is reported rarely, clinicians should maintain a high index of suspicion for it when examining patients with contact lens-associated microbial keratitis. Education on proper contact lens care should be reinforced. Early and appropriate treatment may lead to satisfactory visual outcomes.


Assuntos
Lentes de Contato Hidrofílicas/microbiologia , Úlcera da Córnea/microbiologia , Infecções Oculares Fúngicas/microbiologia , Fusarium/isolamento & purificação , Micoses/microbiologia , Adolescente , Adulto , Antifúngicos/uso terapêutico , Úlcera da Córnea/diagnóstico , Úlcera da Córnea/tratamento farmacológico , Equipamentos Descartáveis , Quimioterapia Combinada , Infecções Oculares Fúngicas/diagnóstico , Infecções Oculares Fúngicas/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/diagnóstico , Micoses/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
20.
Eye Contact Lens ; 33(6 Pt 1): 284-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17993822

RESUMO

PURPOSE: To describe the changing pattern of clinical features and microbiology of contact lens-associated microbial keratitis in Hong Kong. METHODS: This is a retrospective observational case series of patients diagnosed with contact lens-associated microbial keratitis between July 2004 and April 2005 and between July 2005 and April 2006. Patients who wore contact lenses solely for the correction of refractive error and who were seen at Queen Mary Hospital were included in the study. The clinical characteristics, microbiology, and visual outcomes were compared. RESULTS: There were 14 cases between July 2004 and April 2005. Most cases had an axial lesion (eight) or paraxial lesions (four). Corneal scrapings were positive in seven (50%) patients, among whom six showed Pseudomonas aeruginosa and one showed Serratia marcescens as the pathogens. Contact lens storage cases yielded polymicrobial growth in two cases. For the more recent cohort, Fusarium species had been identified as the dominant pathogen, and most (60%) contact lens storage cases showed polymicrobial growth. CONCLUSIONS: There has been an increased number of cases of contact lens-associated fungal keratitis recently. Fusarium species and polymicrobial growth are becoming more dominant.


Assuntos
Lentes de Contato/efeitos adversos , Infecções Oculares/etiologia , Ceratite/microbiologia , Adulto , Idoso , Infecções Bacterianas/epidemiologia , Estudos de Coortes , Córnea/microbiologia , Epidemiologia/tendências , Feminino , Fusarium/isolamento & purificação , Hong Kong/epidemiologia , Humanos , Incidência , Ceratite/patologia , Masculino , Pessoa de Meia-Idade , Micoses/epidemiologia , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/isolamento & purificação , Estudos Retrospectivos , Infecções por Serratia/epidemiologia , Serratia marcescens/isolamento & purificação
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