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1.
Cell ; 164(3): 353-64, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26824653

RESUMO

More than one-half billion people are obese, and despite progress in genetic research, much of the heritability of obesity remains enigmatic. Here, we identify a Trim28-dependent network capable of triggering obesity in a non-Mendelian, "on/off" manner. Trim28(+/D9) mutant mice exhibit a bi-modal body-weight distribution, with isogenic animals randomly emerging as either normal or obese and few intermediates. We find that the obese-"on" state is characterized by reduced expression of an imprinted gene network including Nnat, Peg3, Cdkn1c, and Plagl1 and that independent targeting of these alleles recapitulates the stochastic bi-stable disease phenotype. Adipose tissue transcriptome analyses in children indicate that humans too cluster into distinct sub-populations, stratifying according to Trim28 expression, transcriptome organization, and obesity-associated imprinted gene dysregulation. These data provide evidence of discrete polyphenism in mouse and man and thus carry important implications for complex trait genetics, evolution, and medicine.


Assuntos
Epigênese Genética , Haploinsuficiência , Proteínas Nucleares/genética , Obesidade/genética , Proteínas Repressoras/genética , Magreza/genética , Adolescente , Animais , Índice de Massa Corporal , Criança , Pré-Escolar , Humanos , Camundongos , Inquéritos Nutricionais , Polimorfismo Genético , Proteína 28 com Motivo Tripartido
2.
Nature ; 578(7795): 444-448, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31875646

RESUMO

Metformin, the world's most prescribed anti-diabetic drug, is also effective in preventing type 2 diabetes in people at high risk1,2. More than 60% of this effect is attributable to the ability of metformin to lower body weight in a sustained manner3. The molecular mechanisms by which metformin lowers body weight are unknown. Here we show-in two independent randomized controlled clinical trials-that metformin increases circulating levels of the peptide hormone growth/differentiation factor 15 (GDF15), which has been shown to reduce food intake and lower body weight through a brain-stem-restricted receptor. In wild-type mice, oral metformin increased circulating GDF15, with GDF15 expression increasing predominantly in the distal intestine and the kidney. Metformin prevented weight gain in response to a high-fat diet in wild-type mice but not in mice lacking GDF15 or its receptor GDNF family receptor α-like (GFRAL). In obese mice on a high-fat diet, the effects of metformin to reduce body weight were reversed by a GFRAL-antagonist antibody. Metformin had effects on both energy intake and energy expenditure that were dependent on GDF15, but retained its ability to lower circulating glucose levels in the absence of GDF15 activity. In summary, metformin elevates circulating levels of GDF15, which is necessary to obtain its beneficial effects on energy balance and body weight, major contributors to its action as a chemopreventive agent.


Assuntos
Peso Corporal/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fator 15 de Diferenciação de Crescimento/metabolismo , Metformina/farmacologia , Administração Oral , Adulto , Idoso , Animais , Glicemia/análise , Glicemia/metabolismo , Dieta Hiperlipídica , Método Duplo-Cego , Ingestão de Energia/efeitos dos fármacos , Enterócitos/citologia , Enterócitos/efeitos dos fármacos , Feminino , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/antagonistas & inibidores , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/deficiência , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator 15 de Diferenciação de Crescimento/sangue , Fator 15 de Diferenciação de Crescimento/deficiência , Fator 15 de Diferenciação de Crescimento/genética , Homeostase/efeitos dos fármacos , Humanos , Intestinos/citologia , Intestinos/efeitos dos fármacos , Masculino , Metformina/administração & dosagem , Camundongos , Camundongos Obesos , Pessoa de Meia-Idade , Redução de Peso/efeitos dos fármacos
4.
Proc Natl Acad Sci U S A ; 118(27)2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34187898

RESUMO

An acute increase in the circulating concentration of glucocorticoid hormones is essential for the survival of severe somatic stresses. Circulating concentrations of GDF15, a hormone that acts in the brain to reduce food intake, are frequently elevated in stressful states. We now report that GDF15 potently activates the hypothalamic-pituitary-adrenal (HPA) axis in mice and rats. A blocking antibody to the GDNF-family receptor α-like receptor completely prevented the corticosterone response to GDF15 administration. In wild-type mice exposed to a range of stressful stimuli, circulating levels of both corticosterone and GDF15 rose acutely. In the case of Escherichia coli or lipopolysaccharide injections, the vigorous proinflammatory cytokine response elicited was sufficient to produce a near-maximal HPA response, regardless of the presence or absence of GDF15. In contrast, the activation of the HPA axis seen in wild-type mice in response to the administration of genotoxic or endoplasmic reticulum toxins, which do not provoke a marked rise in cytokines, was absent in Gdf15-/- mice. In conclusion, consistent with its proposed role as a sentinel hormone, endogenous GDF15 is required for the activation of the protective HPA response to toxins that do not induce a substantial cytokine response. In the context of efforts to develop GDF15 as an antiobesity therapeutic, these findings identify a biomarker of target engagement and a previously unrecognized pharmacodynamic effect, which will require monitoring in human studies.


Assuntos
Fator 15 de Diferenciação de Crescimento/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Animais , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Glucocorticoides/metabolismo , Fator 15 de Diferenciação de Crescimento/administração & dosagem , Humanos , Lipopolissacarídeos , Camundongos , Ratos , Tunicamicina/farmacologia
5.
Phys Rev Lett ; 130(11): 111801, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-37001070

RESUMO

We present the first search for the pair production of dark particles X via K_{L}^{0}→XX with X decaying into two photons using the data collected by the KOTO experiment. No signal was observed in the mass range of 40-110 MeV/c^{2} and 210-240 MeV/c^{2}. This sets upper limits on the branching fractions as B(K_{L}^{0}→XX)<(1-4)×10^{-7} and B(K_{L}^{0}→XX)<(1-2)×10^{-6} at the 90% confidence level for the two mass regions, respectively.

6.
Langenbecks Arch Surg ; 408(1): 78, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36745231

RESUMO

PURPOSE: Gastric cancer (GC) is the fifth most common malignancy worldwide and portends a grim prognosis due to a lack of appreciable improvement in 5-year survival. We aimed to analyze the available literature and summarize the current standards of surgical care for curative and palliative intent treatment of GC. METHODS: We conducted a systematic search on the PubMed database for studies on the management of GC. RESULTS: Endoscopic resection is an acceptable treatment option for T1a tumors. The role of optimal resection margin for GC remains unclear. D2 lymph node dissection remains the standard of care with splenectomy needed selectively for splenic hilum involvement. A distal pancreatic resection should be avoided. The advantage of bursectomy and omentectomy in GC surgery is not clear. Multi-visceral resection may be considered for locally advanced GC in carefully selected patients. Minimally invasive approaches are non-inferior to open surgery. Surgery should be abandoned prior even in metastatic GC within the frame of multimodal therapy approach. CONCLUSION: Various trials have conclusively shown improved patient outcomes when well-established surgical standards are followed.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Gastrectomia , Prognóstico , Endoscopia , Pancreatectomia , Excisão de Linfonodo
7.
Eur Cell Mater ; 40: 133-145, 2020 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-32951194

RESUMO

Vascularisation efficiency plays an essential role in the success of bulk transplantation, while biocompatibility and safety are major concerns in clinical applications. Fibrin-based hydrogels have been exploited as scaffolds for their advantages in biocompatibility, degradability and mass transportation in various forms. However, the mechanical strength and degree of vascularisation remain unsatisfactory for clinical usage. An interpenetrating hydrogel was developed by adding hyaluronic acid (HA) to a fibrin-based natural hydrogel. The vasculogenesis of endothelial cells (human umbilical vein endothelial cells, HUVECs) was characterised within the gel using both in vitro and in vivo animal studies. The in vitro vascular morphology analysis showed 17.9 % longer mean tube length and 14.3 % higher average thickness in 7 d cultivation within the HA-supplemented hydrogel. The in vivo results showed 51.6 % larger total tube area, 1.8 × longer average tube length and 81.6 % higher cell number in the HA-supplemented hydrogel compared to the hydrogel without HA. The experimental results demonstrated better vascularisation and cell recruitment in the HA- supplemented hydrogel. The material properties of the hydrogels were also analysed using atomic force microscopy (AFM). The results revealed 3.7 × higher elasticity of the HA-supplemented hydrogel, which provided better mechanical strength and support for easy handling during procedures. With the demonstrated advantages, the developed hydrogels showed promise for exploitation in various practical clinical applications.


Assuntos
Fibrina/farmacologia , Células Endoteliais da Veia Umbilical Humana/fisiologia , Ácido Hialurônico/farmacologia , Hidrogéis/farmacologia , Modelos Biológicos , Neovascularização Fisiológica , Animais , Elasticidade , Fluorescência , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Morfogênese/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos
8.
Proc Natl Acad Sci U S A ; 114(35): 9421-9426, 2017 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-28811369

RESUMO

An intergenic region of human chromosome 2 (2p25.3) harbors genetic variants which are among those most strongly and reproducibly associated with obesity. The gene closest to these variants is TMEM18, although the molecular mechanisms mediating these effects remain entirely unknown. Tmem18 expression in the murine hypothalamic paraventricular nucleus (PVN) was altered by changes in nutritional state. Germline loss of Tmem18 in mice resulted in increased body weight, which was exacerbated by high fat diet and driven by increased food intake. Selective overexpression of Tmem18 in the PVN of wild-type mice reduced food intake and also increased energy expenditure. We provide evidence that TMEM18 has four, not three, transmembrane domains and that it physically interacts with key components of the nuclear pore complex. Our data support the hypothesis that TMEM18 itself, acting within the central nervous system, is a plausible mediator of the impact of adjacent genetic variation on human adiposity.


Assuntos
Apetite/genética , Peso Corporal/genética , Proteínas de Membrana/metabolismo , Obesidade/genética , Animais , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Núcleo Hipotalâmico Paraventricular/metabolismo , Proteínas de Transporte Vesicular
9.
Hong Kong Med J ; 24(3): 218-225, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29807949

RESUMO

INTRODUCTION: Salvage radiotherapy (SRT) provides effective biochemical control for patients with prostate cancer who have prostate specific antigen (PSA) failure after radical prostatectomy. However, the effect of SRT on long-term clinical outcomes remains unknown. Therefore, we report the natural history of patients treated with SRT. METHODS: We identified 84 Chinese patients with prostate cancer treated with SRT to the prostatic fossa alone during 2006-2017 at Tuen Mun Hospital, Hong Kong. Survival was calculated using Kaplan-Meier method. Log-rank test and Cox regression were used to determine significance of clinical parameters with outcomes. RESULTS: Median SRT dose given was 70 Gy (range, 64-76 Gy). Median pre-SRT PSA level was 0.4 ng/mL (0.2-7.4 ng/mL). After SRT, 47 (56%) patients had undetectable (<0.1 ng/mL) PSA levels. After median follow-up of 48 months (2 months to 10 years), 25 (30%) patients had further biochemical progression. Subsequently, 12 patients received androgen deprivation therapy and nine (11%) developed distant metastasis. The 5-year biochemical progression-free survival, androgen deprivation therapy-free survival and metastasis-free survival were 62.7%, 83.5% and 86.7%, respectively. Early PSA failure after radical prostatectomy (hazard ratio 7.4), negative surgical margin (hazard ratio 2.7), positive extracapsular extension (hazard ratio 4.6), and detectable PSA levels after SRT (hazard ratio 17.3) were associated with lower biochemical progression-free survival after SRT. CONCLUSIONS: High-dose SRT with intensity-modulated radiotherapy/volumetric modulated arc radiotherapy is an effective local treatment that can prevent distant metastasis and avoid the need for androgen deprivation therapy in Chinese patients who have PSA failure after radical prostatectomy.


Assuntos
Recidiva Local de Neoplasia/radioterapia , Próstata/patologia , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/radioterapia , Terapia de Salvação , Idoso , Progressão da Doença , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Antígeno Prostático Específico/sangue , Prostatectomia/efeitos adversos , Neoplasias da Próstata/cirurgia , Dosagem Radioterapêutica , Análise de Sobrevida , Resultado do Tratamento
10.
Apoptosis ; 22(3): 369-380, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27878398

RESUMO

Chemotherapy (CT) options in pancreatic cancer (PC) are limited to gemcitabine and 5-fluorouracil (5-FU). Several identified molecular targets in PC represent client proteins of HSP90. HSP90 is a promising target since it interferes with many oncogenic signaling pathways simultaneously. The aim of this study was to evaluate the efficacy of different HSP90 inhibitors in gemcitabine and 5-FU resistant PC. PC cell lines 5061, 5072 and 5156 were isolated and brought in to culture from patients being operated at our institution. L3.6pl cell line served as a control. Anti-proliferative efficacy of three different HSP90 inhibitors (17-AAG, 17-DMAG and 17-AEPGA) was evaluated by the MTT assay. Alterations in signaling pathway effectors and apoptosis upon HSP90 inhibition were determined by western blot analysis and annexin V/PI staining. The cell lines 5061, 5072 and 5156 were resistant to gemcitabine and 5-FU. In contrast 17-AAG and the water-soluble derivates 17-DMAG and 17-AEPGA displayed high anti-proliferative activity in all tested cell lines. The calculated IC50 was below 1 µM. Highly significant down regulation of epidermal-growth-factor-receptor, insulin-like-growth-factor-receptor-1, AKT and MAPK reflected the intracellular molecular signaling-network disruption. Furthermore, besides HSP70 also HSP27 was upregulated in all cell lines. Apoptosis occurred early under HSP90 inhibition and was determined by annexin V/PI staining and CASPASE-3 and PARP assay. In contrast, gemcitabine treated cells did not show any apoptosis. HSP90 inhibition disrupts multiple signaling cascades in gemcitabine and 5-FU resistant PC simultaneously and promotes cancer cell apoptosis. Watersoluble 17-DMAG is equally effective as 17-AAG. HSP27, besides HSP70, may represent an effective response marker of successful HSP90 inhibition.


Assuntos
Adenocarcinoma/tratamento farmacológico , Benzoquinonas/farmacologia , Desoxicitidina/análogos & derivados , Fluoruracila/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Terapia de Alvo Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Fluoruracila/administração & dosagem , Humanos , Concentração Inibidora 50 , Neoplasias Pancreáticas/patologia , Recidiva , Gencitabina
11.
PLoS Genet ; 9(1): e1003166, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23300482

RESUMO

The strongest BMI-associated GWAS locus in humans is the FTO gene. Rodent studies demonstrate a role for FTO in energy homeostasis and body composition. The phenotypes observed in loss of expression studies are complex with perinatal lethality, stunted growth from weaning, and significant alterations in body composition. Thus understanding how and where Fto regulates food intake, energy expenditure, and body composition is a challenge. To address this we generated a series of mice with distinct temporal and spatial loss of Fto expression. Global germline loss of Fto resulted in high perinatal lethality and a reduction in body length, fat mass, and lean mass. When ratio corrected for lean mass, mice had a significant increase in energy expenditure, but more appropriate multiple linear regression normalisation showed no difference in energy expenditure. Global deletion of Fto after the in utero and perinatal period, at 6 weeks of age, removed the high lethality of germline loss. However, there was a reduction in weight by 9 weeks, primarily as loss of lean mass. Over the subsequent 10 weeks, weight converged, driven by an increase in fat mass. There was a switch to a lower RER with no overall change in food intake or energy expenditure. To test if the phenotype can be explained by loss of Fto in the mediobasal hypothalamus, we sterotactically injected adeno-associated viral vectors encoding Cre recombinase to cause regional deletion. We observed a small reduction in food intake and weight gain with no effect on energy expenditure or body composition. Thus, although hypothalamic Fto can impact feeding, the effect of loss of Fto on body composition is brought about by its actions at sites elsewhere. Our data suggest that Fto may have a critical role in the control of lean mass, independent of its effect on food intake.


Assuntos
Composição Corporal/genética , Ingestão de Alimentos/genética , Metabolismo Energético/genética , Oxigenases de Função Mista/genética , Obesidade , Oxo-Ácido-Liases/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Animais , Peso Corporal/genética , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/metabolismo , Homeostase , Humanos , Masculino , Camundongos , Obesidade/genética , Obesidade/metabolismo
12.
Osteoporos Int ; 26(2): 589-99, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25278298

RESUMO

SUMMARY: Kefir treatment in ovariectomized (OVX) rats could significantly decrease the levels of bone turnover markers and prevent OVX-induced bone loss, deterioration of trabecular microarchitecture, and biomechanical dysfunction that may be due to increase intracellular calcium uptake through the TRPV6 calcium channel. INTRODUCTION: Osteoporosis is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to an increased fracture risk. The incidence of osteoporosis increases with age and occurs most frequently in postmenopausal women due to estrogen deficiency, as the balance between bone resorption and bone formation shifts towards increased levels of bone resorption. Among various methods of prevention and treatment for osteoporosis, an increase in calcium intake is the most commonly recommended preventive measure. Kefir is a fermented milk product made with kefir grains that degrade milk proteins into various peptides with health-promoting effects, including immunomodulating-, antithrombotic-, antimicrobial-, and calcium-absorption-enhancing bioactivities. METHODS: The aim of this study is to investigate the effect of kefir on osteoporosis prophylaxis in an ovariectomized rat model. A total of 56 16-week-old female Sprague-Dawley (SD) rats were divided into 7 experimental groups: sham (normal), OVX/Mock, OVX/1X kefir (164 mg/kg BW/day), OVX/2X kefir (328 mg/kg BW/day), OVX/4X kefir (656 mg/kg BW/day), OVX/ALN (2.5 mg/kg BW/day), and OVX/REBONE (800 mg/kg BW/day). After 12-week treatment with kefir, the bone physiology in the OVX rat model was investigated. Accordingly, the aim of this study was to investigate the possible transport mechanism involved in calcium absorption using the Caco-2 human cell line. RESULTS: A 12-week treatment with kefir on the OVX-induced osteoporosis model reduced the levels of C-terminal telopeptides of type I collagen (CTx), bone turnover markers, and trabecular separation (Tb. Sp.). Additionally, treatment with kefir increased trabecular bone mineral density (BMD), bone volume (BV/TV), trabecular thickness (Tb. Th), trabecular number (Tb. N), and the biomechanical properties (hardness and modulus) of the distal femur with a dose-dependent efficacy. In addition, in in vitro assay, we found that kefir increased intracellular calcium uptake in Caco-2 cell through TRPV6 calcium channels and not through L-type voltage-operated calcium channels. CONCLUSION: The protective effect of kefir in the OVX rat model may occur through increasing intracellular calcium uptake through the TRPV6 calcium channel.


Assuntos
Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Produtos Fermentados do Leite , Fêmur/efeitos dos fármacos , Osteoporose Pós-Menopausa/dietoterapia , Animais , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Peptídeos/efeitos dos fármacos , Peptídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
13.
Int J Obes (Lond) ; 38(9): 1172-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24335764

RESUMO

OBJECTIVE: Fatty liver disease is commonly associated with obesity, insulin resistance and diabetes. Severe fatty liver is sometimes accompanied by steatohepatitis and may lead to the development of hepatocellular carcinoma. At present, there is no effective treatment for non-alcoholic fatty liver disease (NAFLD); thus, recent investigations have focused on developing effective therapeutics to treat this condition. This study aimed to evaluate the effects of kefir on the hepatic lipid metabolism of ob/ob mice, which are commonly used to model fatty liver disease. RESULTS: In this study, we used leptin receptor-deficient ob/ob mice as an animal disease model of NAFLD. Six-week-old ob/ob mice were orally administered the dairy product kefir (140 mg kg(-1) of body weight (BW) per day) for 4 weeks. The data demonstrated that kefir improved fatty liver syndrome on BW, energy expenditure and basal metabolic rate by inhibiting serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities (P<0.05) and by decreasing the triglyceride (TG) and total cholesterol (TC) contents of the liver (P<0.05). Oral kefir administration also significantly reduced the macrovesicular fat quantity in liver tissue. In addition, kefir markedly decreased the expression of the genes sterol regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) (P<0.05) but not the expression of peroxisome proliferator-activated receptor α (PPARα) or hepatic carnitine palmitoyltransferase-1α (CPT1α) in the livers of ob/ob mice. CONCLUSION: On the basis of these results, we conclude that kefir improves NAFLD on BW, energy expenditure and basal metabolic rate by inhibiting the lipogenesis pathway and that kefir may have the potential for clinical application to the prevention or treatment of NAFLD.


Assuntos
Produtos Fermentados do Leite/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Metabolismo Basal , Biomarcadores/metabolismo , Western Blotting , Modelos Animais de Doenças , Metabolismo Energético , Regulação da Expressão Gênica , Metabolismo dos Lipídeos , Camundongos , Camundongos Knockout , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Tamanho do Órgão , Receptores para Leptina/deficiência , Transdução de Sinais
14.
J Hum Genet ; 59(12): 661-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25354935

RESUMO

Prognostication of disease relapse and survival is essential for cancer patients and genetic variations in cancer patients may serve as important indicators. A single-nucleotide polymorphism (SNP) mapping to the tumor necrosis factor, alpha-induced protein 3 (TNFAIP3) gene at position 138241110 displays three genotypes (AA, AC and CC). The aim of this study was to evaluate the potential prognostic value of the TNFAIP3-SNP in esophageal cancer (EC). Genomic DNA was extracted from peripheral blood leukocytes of 173 patients who underwent complete surgical resection for EC and did not receive any neoadjuvant or adjuvant therapy. For SNP detection, a 260- bp fragment was PCR amplified, purified and sequenced with tested primers. The product was analyzed by automatic DNA sequencer.The TNFAIP3 genotypes were correlated with clinico-pathological parameters, tumor cell dissemination in bone marrow and clinical outcome. The C-allele carrier presented with higher disease stage (P<0.001). This was predominantly because of the presence of lymph node metastasis (P<0.001). The recurrence rate was higher in C-allele carriers (AC and CC genotype; P=0.004). Kaplan-Meier plots for disease-free (P=0.017) and overall survival (P<0.001) displayed a gene dosage-associated outcome with AA genotype patients presenting the longest and CC genotype patients the poorest survival. In disease stage-adjusted multivariate analysis the TNFAIP3-SNP was identified as an independent prognostic factor for survival (hazard ratio 1.9; P=0.008). The TNFAIP3-SNP allows risk stratification of EC patients and may be a useful tool to identify patients eligible for multimodal therapy concepts.


Assuntos
Proteínas de Ligação a DNA/genética , Neoplasias Esofágicas/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Recidiva Local de Neoplasia/genética , Proteínas Nucleares/genética , Prognóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Intervalo Livre de Doença , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Estudos de Associação Genética , Mutação em Linhagem Germinativa , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Proteína 3 Induzida por Fator de Necrose Tumoral alfa
15.
Eur J Neurol ; 21(5): 797-801, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24629033

RESUMO

BACKGROUND AND PURPOSE: Anosognosia and neglect may coexist in stroke patients. Neglect patients often report poor quality of life (QOL), whereas patients suffering from other cognition disorders with poor insight report better QOL. This study investigates the relationship between anosognosia, neglect and QOL amongst stroke survivors. METHODS: Stroke survivors who met the criteria were used as a sampling pool. Sixty stroke patients were observed in this study, amongst whom 20 patients with anosognosia and neglect (A+N+), 20 patients with neglect but not anosognosia (A-N+) and 20 patients with neither anosognosia nor neglect (A-N-) were selected from the sampling pool based on demographic characteristics matched with the A+N+ group. A questionnaire (SS-QOL) was used to collect the QOL perceived by the stroke survivors. RESULTS: The perceived QOL of the A+N+ group was significantly better than those of the other groups, including the subscales of self-care, mobility, work/productivity, upper extremity, mood, family role and social role. However, the A+N+ group had poor balance level and more fall incidents were reported. CONCLUSION: The A+N+ group perceived better QOL but had more falls and poorer balance than the other groups. Health providers should work with caregivers aggressively in preventing accidents.


Assuntos
Agnosia/etiologia , Lateralidade Funcional/fisiologia , Transtornos da Percepção/etiologia , Qualidade de Vida , Acidente Vascular Cerebral , Adulto , Idoso , Análise de Variância , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/psicologia
16.
Hong Kong Med J ; 20(6): 548-51, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25488036

RESUMO

We report a cluster of acute hepatitis in five air-conditioning maintenance workers following accidental exposure to 2,2-dichloro-1,1,1-trifluoroethane (HCFC-123). They presented to us with complaints of feverishness, generalised malaise, and epigastric discomfort. Their blood biochemistry tests were compatible with acute hepatitis. Viral hepatitis serology, tests for autoimmune hepatitis, and analyses for drugs and alcohol consumption were all negative. No focal hepatic lesion was detected by ultrasound imaging. Percutaneous liver biopsy samples were taken from two of them. The patients were managed with supportive treatment. All had spontaneous, but slow, recovery. Their liver function tests returned to normal after 4 months and their outcomes were favourable. Physicians should be aware of this occupational disease entity.


Assuntos
Etano Clorofluorcarbonos/efeitos adversos , Hepatite/diagnóstico , Fígado/patologia , Doenças Profissionais/diagnóstico , Adulto , Diagnóstico Diferencial , Surtos de Doenças , Hong Kong , Humanos , Exposição por Inalação , Masculino , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional
17.
Am J Nephrol ; 37(4): 291-301, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23548777

RESUMO

BACKGROUND/AIMS: Reactive oxygen species play an important role in the pathogenesis of kidney ischemia/reperfusion injury (IRI) which may be influenced by immunosuppressive therapy. Pertinent to this, we investigated the effects of the mTOR inhibitor everolimus on redox settings and the activity of the anti-oxidative system in kidneys exposed to IRI. METHODS: C57BL/6 mice were subjected to IRI by clamping both renal pedicles for 45 min. Everolimus was applied in daily, subcutaneous doses (0.25 mg/kg body weight), starting 1 day before IRI induction. Both everolimus-treated and non-treated mice were sacrificed at several time points, starting 30 min and finishing 7 days after IRI induction. Markers of oxidation such as glutathione and NADPH levels and anti-oxidative enzyme activities were determined in the kidneys. RESULTS: In comparison to both sham and non-treated animals, the treatment with everolimus resulted in an increased level of markers of oxidation, including a lower level of glutathione, increased level of oxidized glutathione and reduced level of NADPH. The activity of superoxide dismutase was reduced in both experimental groups, but the effects were less pronounced in everolimus-treated animals. In the early phase of reperfusion, everolimus-treated animals showed higher activity of glutathione reductase in comparison to non-treated animals, whereas the activities of glutathione peroxidase and catalase were generally similar. The treatment with everolimus significantly reduced heme oxygenase-1 expression and increased iNOS mRNA expression when compared to non-treated animals. CONCLUSION: Our data imply that everolimus treatment may decrease cytoprotective capacity in kidneys exposed to IRI due to promoted oxidative/nitrosative stress.


Assuntos
Imunossupressores/farmacologia , Rim/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/metabolismo , Sirolimo/análogos & derivados , Animais , Catalase/metabolismo , Everolimo , Glutationa/metabolismo , Dissulfeto de Glutationa , Glutationa Peroxidase/metabolismo , Rim/irrigação sanguínea , Camundongos , Camundongos Endogâmicos C57BL , NADP/metabolismo , Sirolimo/farmacologia , Superóxido Dismutase/metabolismo
18.
Hepatology ; 54(2): 541-54, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21520208

RESUMO

UNLABELLED: Interleukin 2 receptor antagonists (IL-2Ra) are frequently used as induction therapy in liver transplant recipients to decrease the risk of acute rejection while allowing the reduction of concomitant immunosuppression. We conducted a systematic review of prospective, controlled studies to test the hypothesis that the use of IL-2Ra is associated with a decrease in acute rejection and/or a decrease in the side effects of concomitant medication. We performed a search of all major databases and secondary sources from inception to December 2010. Random effects models were used to assess the incidence of acute rejection, graft loss, patient death, and adverse side effects, with or without IL-2Ra. Subgroup analysis and meta-regression were used to explore differences in effect and sources of heterogeneity. Eighteen studies (13 randomized and 5 nonrandomized) met the inclusion and exclusion criteria. Acute rejection at 12 months or later favored the use of IL-2Ra (relative risk [RR] 0.83; 95% confidence interval [CI] 0.76-0.94) and steroid-resistant rejection was also less frequent in patients receiving IL-2Ra (RR 0.66; CI 0.48-0.91). Graft loss and patient death did not differ significantly between treatments. Patients who received IL-2Ra in addition to reduced or delayed calcineurin inhibitors had better renal function (mean difference of estimated glomerular filtration rate: 6.29 mL/min; CI 1.66-10.91) and a lower incidence of renal dysfunction (RR 0.46; CI 0.27-0.78). The use of IL-2Ra was also associated with a lower incidence of posttransplant diabetes mellitus, whereas the incidence of other adverse events was similar. CONCLUSION: The use of IL-2Ra is associated with a lower incidence of acute rejection after transplantation. Concomitant immunosuppression can be reduced, avoiding long-term side effects of immunosuppression.


Assuntos
Rejeição de Enxerto/prevenção & controle , Terapia de Imunossupressão , Transplante de Fígado , Receptores de Interleucina-2/antagonistas & inibidores , Doença Aguda , Ensaios Clínicos Controlados como Assunto , Humanos , Terapia de Imunossupressão/efeitos adversos
19.
Proc Natl Acad Sci U S A ; 106(23): 9350-5, 2009 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-19470471

RESUMO

Tre-2, BUB2, CDC16, 1 domain family member 4 (TBC1D4) (AS160) is a Rab-GTPase activating protein implicated in insulin-stimulated glucose transporter 4 (GLUT4) translocation in adipocytes and myotubes. To determine whether loss-of-function mutations in TBC1D4 might impair GLUT4 translocation and cause insulin resistance in humans, we screened the coding regions of this gene in 156 severely insulin-resistant patients. A female presenting at age 11 years with acanthosis nigricans and extreme postprandial hyperinsulinemia was heterozygous for a premature stop mutation (R363X) in TBC1D4. After demonstrating reduced expression of wild-type TBC1D4 protein and expression of the truncated protein in lymphocytes from the proband, we further characterized the biological effects of the truncated protein in 3T3L1 adipocytes. Prematurely truncated TBC1D4 protein tended to increase basal cell membrane GLUT4 levels (P = 0.053) and significantly reduced insulin-stimulated GLUT4 cell membrane translocation (P < 0.05). When coexpressed with wild-type TBC1D4, the truncated protein dimerized with full-length TBC1D4, suggesting that the heterozygous truncated variant might interfere with its wild-type counterpart in a dominant negative fashion. Two overweight family members with the mutation also manifested normal fasting glucose and insulin levels but disproportionately elevated insulin levels following an oral glucose challenge. This family provides unique genetic evidence of TBC1D4 involvement in human insulin action.


Assuntos
Acantose Nigricans/genética , Proteínas Ativadoras de GTPase/genética , Hiperinsulinismo/genética , Códon sem Sentido , Feminino , Transportador de Glucose Tipo 4/genética , Humanos , Masculino , Linhagem , Mutação Puntual
20.
Hong Kong Med J ; 18(3): 178-85, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22665680

RESUMO

OBJECTIVES: Advance directives have been implemented for years in western countries, but the concept is new to Asian cultures. According to traditional Chinese culture, family members usually play a decisive role in a patient's treatment plan. Thus it may be hard to implement an advance directive despite its importance to the treatment of patients. The objectives of this study were to assess the feasibility of advance directive engagement and to explore significant contributing factors to achieving such a goal. DESIGN: Prospective cohort study. SETTING: Palliative Care Unit of Clinical Oncology, Tuen Mun Hospital, Hong Kong. PATIENTS: The subjects of the investigation were adult patients diagnosed to have advanced malignancy and newly referred to the hospice service from 24 April 2009 to 30 July 2009. Data were collected from nursing assessment forms, locally designed advance directive forms, a checklist completed by oncologists, and details available in the electronic hospital record. RESULTS: Of the 191 eligible patients, 120 (63%) had the advance directive, whereas 71 (37%) did not. In the Cox regression model, the patient having insight of a poor prognosis was the most significant factor facilitating advance directive engagement (P=0.001). Any family objection in the discussion of advance directives was also an important factor, though it did not reach statistical significance (P=0.082). Other factors like age, gender, education, religion, financial status, living environment, understanding the diagnosis, bereavement experience, type of cancer, nature of illness, courses of chemotherapy or radiotherapy received, main caregiver, in-house supporter, nurse-led clinic attendance, clinical psychologist consultation, and in-patient hospice nurse coordinator interview were all statistically insignificant. CONCLUSIONS: Our study demonstrated that it was feasible to discuss an advance directive with Chinese patients with advanced malignancy. When patients have insight about their poor prognosis and family members have no objection, it may be appropriate to discuss an advance directive.


Assuntos
Diretivas Antecipadas , Povo Asiático , Cuidados Paliativos na Terminalidade da Vida , Neoplasias/etnologia , Assistência Terminal , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Comunicação , Família , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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