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1.
Malays J Pathol ; 45(2): 195-204, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37658529

RESUMO

INTRODUCTION: Extracellular vesicles (exosome-like vesicles) are small membrane vesicles ranging from 20-200nm in size that are released by various cells into the extracellular space. These extracellular vesicles play a major role in cell-to-cell communication and contain materials, such as proteins, mRNAs, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). The effect of exosomes derived from an invasive colon cancer cell line on angiogenesis is unclear. Hence, the aim of this study is to investigate the effect of exosomes derived from an invasive colon cancer cell line on angiogenesis of endothelial cells. MATERIALS AND METHODS: In the present study, the exosomes from the cell culture supernatants of an invasive colon cancer cell line SW480-7 were characterised. The effect on tube formation and expression of angiogenic genes in a microvascular endothelial cell, telomerase-immortalised microvascular endothelial cell (TIME) was examined after co-cultured with exosomes secreted from SW480-7. RESULTS: Zetasizer result showed average diameter of exosomes derived from SW480-7 was 246.2 nm and morphological analysis showed the size of majority of exosomes were less than 200 nm. Results showed that exosomes derived from SW480-7 increased tube formation and up-regulated FGFR3 mRNA expression in TIME. CONCLUSION: Our findings suggest that exosomes derived from SW480-7 increased tube formation and up-regulated expression of FGFR3 mRNA in TIME.

2.
Hong Kong Med J ; 25(1): 64-7, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30648830

RESUMO

The Hong Kong Reference Framework for Hypertension Care for Adults in Primary Care Settings is updated regularly to ensure it reflects the latest medical development and best practice. In 2017, guidelines from the United States included a major change, adopting the lower blood pressure values of 130/80 mm Hg in defining hypertension, in contrast to the prevailing international consensus of 140/90 mm Hg. After thorough review of the literature and international guidelines, the Advisory Group on Hong Kong Reference Framework for Care of Diabetes and Hypertension in Primary Care Settings (Advisory Group) recommends that the definition of hypertension adopted in the Reference Framework should remain unchanged as a blood pressure of ≥140/90 mm Hg, as there is currently inadequate evidence and lack of general consensus to support such change in Hong Kong. The Advisory Group agrees on individualised treatment goals, and recommends that the initial blood pressure goal for individuals with uncomplicated hypertension should be <140/90 mm Hg; for those who can tolerate it, the goal should be ≤130/80 mm Hg. A lower blood pressure is advisable for young or overweight/obese patients, smokers, and patients with other cardiovascular risk factors.


Assuntos
Fidelidade a Diretrizes , Hipertensão/terapia , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde/métodos , Pressão Sanguínea , Objetivos , Hong Kong , Humanos , Hipertensão/diagnóstico
3.
Leukemia ; 28(11): 2229-34, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24732597

RESUMO

With advent of several treatment options in multiple myeloma (MM), a selection of effective regimen has become an important issue. Use of gene expression profile (GEP) is considered an important tool in predicting outcome; however, it is unclear whether such genomic analysis alone can adequately predict therapeutic response. We evaluated the ability of GEP to predict complete response (CR) in MM. GEP from pretreatment MM cells from 136 uniformly treated MM patients with response data on an IFM, France led study were analyzed. To evaluate variability in predictive power due to microarray platform or treatment types, additional data sets from three different studies (n=511) were analyzed using same methods. We used several machine learning methods to derive a prediction model using training and test subsets of the original four data sets. Among all methods employed for GEP-based CR predictive capability, we got accuracy range of 56-78% in test data sets and no significant difference with regard to GEP platforms, treatment regimens or in newly diagnosed or relapsed patients. Importantly, permuted P-value showed no statistically significant CR predictive information in GEP data. This analysis suggests that GEP-based signature has limited power to predict CR in MM, highlighting the need to develop comprehensive predictive model using integrated genomics approach.


Assuntos
Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Transcriptoma , Testes Genéticos , Humanos , Análise em Microsséries , Indução de Remissão , Prevenção Secundária , Sensibilidade e Especificidade
4.
Clin Exp Allergy ; 44(2): 231-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24447085

RESUMO

BACKGROUND: Between 75 000 and 125 000 U.S. infants are hospitalized for respiratory syncytial virus (RSV) bronchiolitis every year. Up to half will be diagnosed with asthma in later childhood. Vitamin D deficiency has been associated with susceptibility to asthma and respiratory infections. Measured vitamin D is largely bound to vitamin D-binding protein (VDBP); VDBP levels are influenced by its gene (GC) haplotype. OBJECTIVE: We assessed the relationship between polymorphisms rs7041 and rs4588, which define haplotypes GC1s, GC1f, and GC2, and RSV bronchiolitis susceptibility and subsequent asthma. METHODS: We retrospectively recruited 198 otherwise healthy children (93% White) hospitalized for severe RSV bronchiolitis in Boston and 333 parents into a follow-up study to assess asthma diagnosis. Data were analysed using family-based genetic association tests. We independently validated our results in 465 White children hospitalized with RSV bronchiolitis and 930 White population controls from the Netherlands. RESULTS: The rs7041_C allele (denoting haplotype GC1s) was overtransmitted (P = 0.02, additive model) in the entire Boston cohort, in Whites (P = 0.03), and especially in children subsequently diagnosed with asthma (P = 0.006). The GC1f haplotype was undertransmitted in the asthma subgroups (all races and White, both P < 0.05). The rs7041_C allele was also more frequent in the RSV bronchiolitis group compared with controls (OR 1.12, 95% CI 1.02, 1.4, P = 0.03) in the Netherlands, especially in mechanically ventilated patients (P = 0.009). CONCLUSION AND CLINICAL RELEVANCE: GC1s haplotype carriage may increase the risk of RSV bronchiolitis in infancy and subsequent asthma development. The GC1s haplotype is associated with higher VDBP levels, resulting in less freely available vitamin D. KEY MESSAGES: Vitamin D-binding protein (VDBP) haplotypes influence free vitamin D levels. We report an association between a VDBP haplotype and hospitalization for RSV bronchiolitis in infancy in two independent cohorts.


Assuntos
Bronquiolite Viral/genética , Haplótipos , Polimorfismo de Nucleotídeo Único , Infecções por Vírus Respiratório Sincicial/genética , Vírus Sincicial Respiratório Humano , Proteína de Ligação a Vitamina D/genética , Bronquiolite Viral/sangue , Bronquiolite Viral/epidemiologia , Bronquiolite Viral/terapia , Pré-Escolar , Feminino , Seguimentos , Hospitalização , Humanos , Lactente , Masculino , Infecções por Vírus Respiratório Sincicial/sangue , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/terapia , Estudos Retrospectivos , Vitamina D/sangue , Proteína de Ligação a Vitamina D/sangue
5.
Cell Prolif ; 45(2): 132-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22309282

RESUMO

BACKGROUND: Mesenchymal stem cells (MSC) have great potential in regenerative medicine, immunotherapy and gene therapy due to their unique properties of self-renewal, high plasticity, immune modulation and ease for genetic modification. However, production of MSC at sufficient clinical scale remains an issue as in vitro generation of MSC inadequately fulfils the demand with respect to patients. OBJECTIVES: This study has aimed to establish optimum conditions to generate and characterize MSC from human umbilical cord (UC-MSC). MATERIALS AND METHODS: To optimize MSC population growth, basic fibroblast growth factor (bFGF) was utilized in culture media. Effects of bFGF on expansion kinetics, cell cycle, survival of UC-MSC, cytokine secretion, expression of early stem-cell markers and immunomodulation were investigated. RESULTS: bFGF supplementation profoundly enhanced UC-MSC proliferation by reducing population doubling time without altering immunophenotype and immunomodulatory function of UC-MSC. However, cell cycle studies revealed that bFGF drove the cells into the cell cycle, as a higher proportion of cells resided in S phase and progressed into M phase. Consistent with this, bFGF was shown to promote expression of cyclin D proteins and their relevant kinases to drive UC-MSC to transverse cell cycle check points, thus, committing the cells to DNA synthesis. Furthermore, supplementation with bFGF changed the cytokine profiles of the cells and reduced their apoptotic level. CONCLUSION: Our study showed that bFGF supplementation of UC-MSC culture enhanced the cells' growth kinetics without compromising their nature.


Assuntos
Fator 2 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Cordão Umbilical/citologia , Apoptose/efeitos dos fármacos , Comunicação Celular/imunologia , Técnicas de Cultura de Células , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/biossíntese , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citocinas/biossíntese , Feminino , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Humanos , Metaloproteinase 3 da Matriz/metabolismo , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Gravidez , Linfócitos T/imunologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Clin Exp Immunol ; 155(3): 412-22, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19220831

RESUMO

The pathological significance of the mechanisms of tumour immune-evasion and/or immunosuppression, such as loss of T cell signalling and increase in regulatory T cells (T(regs)), has not been well established in the nasopharyngeal carcinoma (NPC) microenvironment. To evaluate the T(reg) immunophenotypes in tumour-infiltrating lymphocytes (TILs), we performed a double-enzymatic immunostaining for detection of forkhead box P3 (FoxP3) and other markers including CD4, CD8, and CD25 on 64 NPC and 36 non-malignant nasopharyngeal (NP) paraffin-embedded tissues. Expression of CD3 zeta and CD3 epsilon was also determined. The prevalence of CD4(+)FoxP3(+) cells in CD4(+) T cells and the ratio of FoxP3(+)/CD8(+) were increased significantly in NPC compared with those in NP tissues (P < 0.001 and P = 0.025 respectively). Moreover, the ratio of FoxP3(+)/CD25(+)FoxP3(-) in NPC was significantly lower than that in NP tissues (P = 0.005), suggesting an imbalance favouring activated phenotype of T cells in NPC. A significant negative correlation between the abundance of FoxP3(+) and CD25(+)FoxP3(-) cells (P < 0.001) was also identified. When histological types of NPC were considered, a lower ratio of FoxP3(+)/CD25(+)FoxP3(-) was found in non-keratinizing and undifferentiated carcinomas. Increased CD4(+)FoxP3(+)/CD4(+) proportion and FoxP3(+)/CD8(+) ratio were associated with keratinizing squamous cell carcinoma. A reduced expression of CD3 zeta in TILs was found in 20.6% of the NPC tissues but none of the NP tissues. These data provide evidence for the imbalances of T(reg) and effector T cell phenotypes and down-regulation of signal-transducing molecules in TILs, supporting their role in suppression of immune response and immune evasion of NPC.


Assuntos
Carcinoma/imunologia , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Nasofaríngeas/imunologia , Linfócitos T Reguladores/imunologia , Biomarcadores/análise , Complexo CD3/análise , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Carcinoma de Células Escamosas/imunologia , Feminino , Fatores de Transcrição Forkhead/análise , Humanos , Imuno-Histoquímica , Subunidade alfa de Receptor de Interleucina-2/análise , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Nasofaringe/imunologia , Estatísticas não Paramétricas
7.
Water Res ; 35(4): 1029-37, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11235868

RESUMO

Reduction of excess sludge in an oxic-settling-anoxic (OSA) activated sludge process might be attributed to a "sludge fasting (insufficient food under an anoxic condition)/feasting (sufficient food under an oxic condition)" treatment. This paper was to examine this explanation by investigating both the sludge fasting/feasting phenomenon and the effect of a fasting/feasting treatment on sludge growth. In this study, five different activated sludge cultures cultivated using synthetic wastewater composed of mainly glucose and other necessary nutrients: (1) an aerobic batch culture, (2) an intermittently aerated batch culture, (3) an anoxic batch culture, (4) a continuous aerobic culture, and (5) an OSA culture, were employed. It was found that only the aerobic batch culture and the aerobic continuous culture are fastable when the oxidation reduction potential (ORP) level is below 100 mV under no-food condition during a 2-h fasting treatment, showing that both the biomass and carbohydrate storage of these two cultures were reduced after the treatment. When the fasted cultures were treated in a feasting environment, an accumulation of carbohydrate storage did not occur, while specific oxygen uptake rates (SOUR) showed a sharp increase. Both the substrate utilization and biomass growth rates were also accelerated. It was therefore confirmed that a sludge feasting did occur after a fasting treatment for the fastable cultures. However, an increase in sludge ATP content was not brought about by the feasting treatment. The sludge fasting/feasting treatment in this paper could not induce a reduction of the observed growth yield (Y(obs)) in all the cultures cultivated with glucose-based synthetic wastewater.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos/métodos , Trifosfato de Adenosina/metabolismo , Aerobiose , Anaerobiose , Reatores Biológicos , Metabolismo dos Carboidratos , Oxirredução , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/instrumentação
8.
Proc Natl Acad Sci U S A ; 95(17): 10334-9, 1998 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-9707648

RESUMO

Many terrestrial plants respond to flooding with enhanced ethylene production. The roots of flooded plants produce 1-aminocyclopropane-1-carboxylic acid (ACC), which is transported from the root to the shoot, where it is converted to ethylene. In the roots, ACC is synthesized by ACC synthase, which is encoded by a multigene family. Previously, we identified two ACC synthase genes of tomato that are involved in flooding-induced ethylene production. Here, we report the cloning of LE-ACS7, a new tomato ACC synthase with a role early during flooding but also in the early wound response of leaves. The promoter of LE-ACS7 is tagged by a Sol3 transposon. A Sol3 transposon is also present in the tomato polygalacturonase promoter to which it conferred regulatory elements. Thus, Sol3 transposons may affect the regulation of LE-ACS7 and may be involved in the communication between the root and the shoot of waterlogged tomato plants.


Assuntos
Genes de Plantas , Liases/genética , Solanum lycopersicum/enzimologia , Solanum lycopersicum/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Primers do DNA/genética , Elementos de DNA Transponíveis , DNA Complementar/genética , DNA de Plantas/genética , Etilenos/biossíntese , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/metabolismo , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Homologia de Sequência do Ácido Nucleico , Sitios de Sequências Rotuladas , Água
9.
Br J Pharmacol ; 107(1): 146-51, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1358380

RESUMO

1. Short-circuit current (SCC) technique was used to study the adrenoceptors involved in the electrogenic chloride secretion by cultured cauda epididymal epithelium of rats. Stimulation of the epithelium with noradrenaline (primarily beta 1-adrenoceptor selective agonist), salbutamol (beta 2-adrenoceptor selective agonist) and adrenaline (non-selective beta-adrenoceptor agonist) led to a rise in SCC. At a low chart-speed (2 mm min-1), the response profile to these agonists consisted of a peak followed by a sustained response considerably higher than the basal SCC. 2. The EC50s (doses of agonist producing 50% maximum response) of noradrenaline, salbutamol and adrenaline were 300, 115 and 10 nM respectively. Pretreating the tissues with 1 microM atenolol (beta 1-selective antagonist) and 10 microM butoxamine (beta 2-selective antagonist) shifted the dose-response curves of noradrenaline (shifted EC50 = 4000 nM) and salbutamol (shifted EC50 = 1050 nM) to the right. Atenolol (1 microM) and butoxamine (10 microM) shifted the dose-response curve of adrenaline to the right with new EC50s of 30 nM and 115 nM, respectively. 3. The rapidly rising phase of the SCC response to noradrenaline and adrenaline observed at low chart-speed consisted of a brief and transient retraction followed by a rebound increase in SCC. At a high chart-speed (1 mm s-1), the retraction and rebound phenomenon manifested as a fast initial spike which could be blocked by phentolamine (non-specific alpha-adrenoceptor antagonist) in a dose-dependent fashion. Similar initial spikes were observed when the tissues were stimulated with phenylephrine (alpha-selective agonist) but not with isoprenaline (non-selective beta-agonist) or forskolin (activator of adenylate cyclase). The response of the initial spike triggered by noradrenaline was dose-dependent and the EC50 was 2000 nM.4. The present study showed that the electrogenic chloride secretion by rat epididymis could be stimulated by (alphaxi-, beta131- and beta2-adrenoceptor agonists. The al-mediated response had a faster onset and more transient action than the 3-counterpart. It is postulated that epididymal chloride secretion might be regulated by neural (noradrenaline-mediated) and humoral (adrenaline-mediated) controls and that the stimulus-secretion coupling mechanisms might involve both Ca2+(alpha-mediated response) and adenosine 3':5'-cyclic monophosphate (beta-mediated response) as intracellular second messengers.


Assuntos
Cloretos/metabolismo , Epididimo/metabolismo , Receptores Adrenérgicos alfa/fisiologia , Receptores Adrenérgicos beta/fisiologia , Agonistas alfa-Adrenérgicos/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Animais , Cálcio/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , Epididimo/efeitos dos fármacos , Epitélio/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
10.
Proc Natl Acad Sci U S A ; 89(6): 2475-9, 1992 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-1549612

RESUMO

Degenerate oligonucleotide primers corresponding to conserved regions flanking the active-site domain of 1-aminocyclopropane-1-carboxylate (ACC) synthase (EC 4.4.1.14) were used for the polymerase chain reaction (PCR) to amplify DNA fragments from mRNA isolated from tomato fruit and tomato suspension cell culture. Antibodies raised against two conserved peptide sequences (TNPSNPLGTT and SLSKDLGLPGFRVG) were used to screen for positive colonies, after the PCR products were cloned into a Bluescript plasmid and expressed in Escherichia coli. Four distinct cDNA fragments encoding ACC synthase homologs were isolated. While pBTAS1 and pBTAS4 were obtained from fruit mRNA, cell culture mRNA yielded three sequences, pBTAS1, pBTAS2, and pBTAS3. Sequencing of these gene fragments revealed that pBTAS1 and pBTAS4 were identical to those full-length sequences previously reported by Van Der Straeten et al. [Van Der Straeten, D., Van Wiemeersch, L., Goodman, H. & Van Montague, M. (1990) Proc. Natl. Acad. Sci. USA 87, 4859-4863] and Olson et al. [Olson, D. C., White, J. A., Edelman, J., Harkin, R. N. & Kende, H. (1991) Proc. Natl. Acad. Sci. USA 88, 5340-5344] from tomato fruit, whereas pBTAS2 and pBTAS3 represent new sequences. Ribonuclease protection assays were used to examine the expression of these transcripts under three different conditions of enhanced ethylene production--namely, during fruit ripening, in response to mechanical wounding in fruit tissue, and auxin stimulation in vegetative tissue. Transcripts of pBTAS1 accumulated massively during ripening and wounding but only slightly in response to auxin treatment. Although pBTAS4 was associated with fruit ripening, it was unresponsive to auxin treatment in vegetative tissue. In contrast, the expression of pBTAS2 and pBTAS3 was greatly promoted in auxin-treated vegetative tissue but was absent from fruit tissue. While the expression of pBTAS2 was moderately dependent on wounding, pBTAS3 was unresponsive to wounding. These data support the view that ACC synthase is encoded by a multigene family and that the members are differentially expressed in response to developmental, environmental, and hormonal factors.


Assuntos
Liases/genética , Família Multigênica , Plantas/enzimologia , Transcrição Gênica , Sequência de Aminoácidos , Anticorpos , Sequência de Bases , Clonagem Molecular , DNA/genética , DNA/isolamento & purificação , Liases/análise , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Peptídeos/síntese química , Peptídeos/imunologia , Plantas/genética , Plasmídeos , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico
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