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1.
Ther Adv Musculoskelet Dis ; 13: 1759720X211035196, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394749

RESUMO

Systemic sclerosis (SSc) is a rare rheumatic disease characterised by inflammation, vasculopathy and fibrosis of skin and internal organs. A common complication and a leading cause of death in SSc is interstitial lung disease (ILD). The current armamentarium of treatments in SSc-ILD mainly includes immunosuppressive therapies and has recently been expanded with anti-fibrotic agent nintedanib. Autologous stem cell transplantation (SCT) is increasingly used in progressive diffuse cutaneous SSc. This intensive treatment has been studied in three randomised trials and demonstrated to improve survival and quality of life. In the subsets of patients with SSc-ILD, SCT resulted in stabilisation and modest improvement of lung volumes and disease extent on high resolution computed tomography, but less impact was seen on diffusion capacity. Comparison of SCT outcomes with results from SSc-ILD trials is difficult though, as lung involvement per se was not an inclusion criterion in all SCT trials. Also, baseline characteristics differed between studies. The risk of severe treatment-related complications from SCT is still considerable and patients with extensive lung disease are particularly at risk of complications during transplantation. Therefore SCT should only be provided by experienced multidisciplinary teams in carefully selected patients. Future research needs to include comprehensive pulmonary evaluation and establish whether SCT early in the disease might prevent irreversible pulmonary damage and reduce treatment-related complications. Also, more insight in mechanisms of action of SCT in the lung and predictors for response will improve the use of this treatment in SSc-ILD. In this review the role of SCT in the treatment of SSc-ILD is summarised.

3.
Hum Reprod ; 33(1): 156-165, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29136189

RESUMO

STUDY QUESTION: Are serum polyunsaturated fatty acids (PUFA) concentrations, including omega-3 (ω3-PUFA) and omega-6 (ω6-PUFA), related to ART outcomes? SUMMARY ANSWER: Serum levels of long-chain ω3-PUFA were positively associated with probability of live birth among women undergoing ART. WHAT IS KNOWN ALREADY: Intake of ω3-PUFA improves oocyte and embryo quality in animal and human studies. However, a recent cohort study found no relation between circulating ω3-PUFA levels and pregnancy rates after ART. STUDY DESIGN SIZE, AND DURATION: This analysis included a random sample of 100 women from a prospective cohort study (EARTH) at the Massachusetts General Hospital Fertility Center who underwent 136 ART cycles within one year of blood collection. PARTICIPANTS/MATERIALS, SETTING, METHODS: Serum fatty acids (expressed as percentage of total fatty acids) were measured by gas chromatography in samples taken between Days 3 and 9 of a stimulated cycle. Primary outcomes included the probability of implantation, clinical pregnancy and live birth per initiated cycle. Cluster-weighted generalized estimating equation (GEE) models were used to analyze the association of total and specific PUFAs with ART outcomes adjusting for age, body mass index, smoking status, physical activity, use of multivitamins and history of live birth. MAIN RESULTS AND ROLE OF CHANCE: The median [25th, 75th percentile] serum level of ω3-PUFA was 4.7% [3.8%, 5.8%] of total fatty acids. Higher levels of serum long-chain ω3-PUFA were associated with higher probability of clinical pregnancy and live birth. Specifically, after multivariable adjustment, the probability of clinical pregnancy and live birth increased by 8% (4%, 11%) and 8% (95% CI: 1%, 16%), respectively, for every 1% increase in serum long-chain ω3-PUFA levels. Intake of long-chain ω3-PUFA was also associated with a higher probability of life birth in these women, with RR of 2.37 (95% CI: 1.02, 5.51) when replacing 1% energy of long-chain ω3-PUFA for 1% energy of saturated fatty acids. Serum ω6-PUFA, ratios of ω6 and ω3-PUFA, and total PUFA were not associated with ART outcomes. LIMITATIONS REASONS FOR CAUTION: The generalizability of the findings to populations not undergoing infertility treatment may be limited. The use of a single measurement of serum fatty acids to characterize exposure may lead to potential misclassification during follow up. WIDER IMPLICATIONS OF THE FINDINGS: Serum ω3-PUFA are considered biomarkers of dietary intake. The association of higher serum long chain ω3-PUFA levels with improved ART outcomes suggests that increased intake of these fats be may be beneficial for women undergoing infertility treatment with ART. STUDY FUNDING/COMPETING INTERESTS: NIH grants R01-ES009718 from the National Institute of Environmental Health Sciences, P30-DK046200 and T32-DK007703-16 from the National Institute of Diabetes and Digestive and Kidney Diseases, and L50-HD085359 from the National Institute of Child Health and Human Development, and the Early Life Nutrition Fund from Danone Nutricia US. Dr Rueda is involved in a patent 9,295,662, methods for enhancing, improving, or increasing fertility or reproductive function (http://patents.com/us-9295662.html). This patent, however, does not lead to financial gain for Dr Rueda, or for Massachusetts General Hospital. Dr Rueda does not own any part of the company nor does he have any equity in any fertility related company. As Dr Rueda is not a physician, he does not evaluate patients or prescribe medications. All other coauthors have no conflicts of interest to declare.


Assuntos
Ácidos Graxos Ômega-3/sangue , Técnicas de Reprodução Assistida , Adulto , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Infertilidade/sangue , Infertilidade/terapia , Nascido Vivo , Massachusetts , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Prospectivos , Resultado do Tratamento
4.
Hum Reprod ; 32(9): 1846-1854, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28854726

RESUMO

STUDY QUESTION: Is pre-treatment alcohol and caffeine intake associated with infertility treatment outcomes among women undergoing ART? SUMMARY ANSWER: Low to moderate alcohol and caffeine intakes in the year prior to infertility treatment were not related to ART outcomes. WHAT IS KNOWN ALREADY: Alcohol and caffeine intake have been found to be associated with infertility in some studies. Nevertheless, data on their relation with outcomes of infertility treatments are scarce and inconsistent. STUDY DESIGN, SIZE, DURATION: We included 300 women (493 ART cycles) from the Environment and Reproductive Health Study, an ongoing cohort study (2006-2016). PARTICIPANTS/MATERIALS, SETTING, METHODS: Pre-treatment intakes of alcohol and caffeine were assessed retrospectively using a validated food frequency questionnaire. Intermediate and clinical endpoints of ART were abstracted from electronic medical records. Generalized linear mixed models with random intercepts to account for multiple ART cycles per woman were used to evaluate the association with ART outcomes adjusting for age, BMI, smoking status, infertility diagnosis, protocol type, race, dietary patterns, and calories, vitamin B12 and folate intake. MAIN RESULTS AND THE ROLE OF CHANCE: Median (range) pre-treatment alcohol and caffeine intakes were 5.6 (0.0-85.8) g/day and 124.9 (0.3-642.2) mg/day, respectively. The adjusted percentage of initiated cycles resulting in live birth (95% CI) for women in increasing categories of pre-treatment alcohol intake was 34% (20, 52%) for non-consumers, 46% (36, 57%) for 0.1-6 g/day, 41% (29, 53%) for 6.1-12 g/day, 42% (31, 55%) for 12.1-24 g/day, and 41% (22, 63%) for >24 g/day (P, trend = 0.87). The adjusted percentage of cycles resulting in live birth (95% CI) for women in increasing categories of caffeine intake was 46% (36-57%) for <50 mg/day, 44% (29, 60%) for 50.1-100 mg/day, 42% (31, 53%) for 100.1-200 mg/day, 40% (28, 53%) for 200.1-300 mg/day and 40% (21, 63%) for >300 mg/day (P, trend = 0.34). When specific types of alcoholic and caffeinated beverages were evaluated, no relations with ART treatment outcomes were observed. LIMITATIONS, REASONS FOR CAUTION: Residual confounding by other diet and lifestyle factors cannot be ruled out owing to the observational nature of this study. It is also unclear how generalizable these results are to women who are conceiving without the assistance of ART. WIDER IMPLICATIONS OF THE FINDINGS: Our results provide reassurance that low to moderate intakes of alcohol (e.g. ≤12 g/day) and caffeine (e.g. <200 mg/day) in the year prior to infertility treatment initiation do not have an adverse effect on intermediate or clinical outcomes of ART. STUDY FUNDING/COMPETING INTEREST(S): The authors are supported by National Institutes of Health (NIH) grants ES022955, R01ES009718, R01ES000002, P30DK46200 and L50-HD085359. No conflicts of interest to declare. TRIAL REGISTRATION NUMBER: NCT00011713.


Assuntos
Consumo de Bebidas Alcoólicas , Cafeína , Infertilidade Feminina/terapia , Técnicas de Reprodução Assistida , Adulto , Estudos de Coortes , Feminino , Humanos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Resultado do Tratamento
5.
BJOG ; 124(10): 1547-1555, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28278351

RESUMO

OBJECTIVE: To evaluate the association between protein intake (amount and type) and antral follicle count (AFC). DESIGN: Prospective cohort. SETTING: Academic fertility centre. POPULATION: Two hundred and sixty-five women undergoing fertility treatments at an academic fertility centre and participating in an ongoing study on environment and reproductive health. METHODS: We measured AFC in ultrasonographic evaluation among women undergoing infertility treatments. Women completed a previously validated semi-quantitative food frequency questionnaire. We used Poisson regression to evaluate the relation between protein intake and AFC while adjusting for age, body mass index, race, smoking status, and total energy intake. MAIN OUTCOME MEASURES: Antral follicle count. RESULTS: Among 265 women (mean age: 35.0 ± 3.9 years, 85% Caucasian), total protein intake (% energy) was unrelated to AFC. When protein from different food sources was considered separately, we found a negative association between dairy protein intake and AFC. The mean AFC was 14.4% (3.9-23.7%) lower for women in the highest quintile of dairy protein intake than for women in the bottom quintile after adjusting for potential confounders (P-trend = 0.04). This association was stronger among women who had never smoked (P-trend = 0.002) but was not observed among previous smokers (P-trend = 0.36). There were no associations between protein intake from either non-dairy animal or vegetable sources and AFC. CONCLUSION: Higher dairy protein intake (≥5.24% of energy) was associated with lower antral follicle counts among women presenting for infertility treatment. These findings should be further investigated in prospective studies also designed to clarify the biology underlying the observed associations. TWEETABLE ABSTRACT: Higher dairy protein intake was associated with lower antral follicle counts in an infertile population.


Assuntos
Laticínios/efeitos adversos , Proteínas Alimentares/efeitos adversos , Ingestão de Alimentos/fisiologia , Infertilidade Feminina/fisiopatologia , Folículo Ovariano , Adulto , Laticínios/análise , Inquéritos sobre Dietas , Proteínas Alimentares/análise , Feminino , Humanos , Infertilidade Feminina/diagnóstico por imagem , Infertilidade Feminina/terapia , Distribuição de Poisson , Estudos Prospectivos , Análise de Regressão
6.
Hum Reprod ; 31(3): 563-71, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26787645

RESUMO

STUDY QUESTION: Is dairy food consumption associated with live birth among women undergoing infertility treatment? SUMMARY ANSWER: There was a positive association between total dairy food consumption and live birth among women ≥35 years of age. WHAT IS KNOWN ALREADY: Dairy food intake has been previously related to infertility risk and measures of fertility potential but its relation to infertility treatment outcomes are unknown. STUDY DESIGN, SIZE, DURATION: Our study population comprised a total of 232 women undergoing 353 in vitro fertilization (IVF) treatment cycles between February 2007 and May 2013, from the Environment and Reproductive Health study, an ongoing prospective cohort. PARTICIPANTS/MATERIALS, SETTING, METHODS: Diet was assessed before assisted reproductive technology (ART) treatment using a validated food frequency questionnaire. Study outcomes included ovarian stimulation outcomes (endometrial thickness, estradiol levels and oocyte yield), fertilization rates, embryo quality measures and clinical outcomes (implantation, clinical pregnancy and live birth rates). We used generalized linear mixed models with random intercepts to account for multiple ART cycles per woman while simultaneously adjusting for age, caloric intake, BMI, race, smoking status, infertility diagnosis, protocol type, alcohol intake and dietary patterns. MAIN RESULTS AND THE ROLE OF CHANCE: The age- and calorie-adjusted difference in live birth between women in the highest (>3.0 servings/day) and lowest (<1.34 servings/day) quartile of dairy intake was 21% (P = 0.02). However, after adjusting for additional covariates, this association was observed only among women ≥35 years (P, interaction = 0.04). The multivariable-adjusted live birth (95% CI) in increasing quartiles of total dairy intake was 23% (11, 42%), 39% (24, 56%), 29% (17, 47%) and 55% (39, 69%) (P, trend = 0.02) among women ≥35 years old, and ranged from 46 to 54% among women <35 years old (P, trend = 0.69). There was no association between dairy intake and any of the intermediate outcomes. LIMITATIONS, REASONS FOR CAUTION: The lack of a known biological mechanism linking dairy intake to infertility treatment outcomes calls for caution when interpreting these results and for additional work to corroborate or refute them. WIDER IMPLICATIONS OF THE FINDINGS: Dairy intake does not appear to harm IVF outcomes and, if anything, is associated with higher chances of live birth. STUDY FUNDING/COMPETING INTERESTS: This work was supported by NIH grants R01-ES009718 and R01ES000002 from NIEHS, P30 DK046200 from NIDDK and T32HD060454 from NICHD. M.C.A. was supported by a Ruth L. Kirschstein National Research Service Award T32 DK 007703-16 from NIDDK. She is currently employed at the Nestlé Research Center, Switzerland and completed this work while at the Harvard School of Public Health. The other authors declare no conflicts of interest.


Assuntos
Laticínios , Dieta , Fertilização in vitro , Infertilidade/terapia , Adulto , Ingestão de Alimentos , Feminino , Humanos , Modelos Lineares , Gravidez , Taxa de Gravidez , Fatores de Risco , Resultado do Tratamento
7.
Int J Sports Med ; 34(9): 841-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23444084

RESUMO

This study compares the serological markers between runners who are hepatitis B virus carries (HBVc) and runners who are non-HBVc in a 100-km ultra-marathon race. Blood samples of 8 HBVc and 18 non-HBVc runners were drawn 1 week before, immediately following, and 24 h after the race. Samples were analyzed and compared between the 2 groups for liver function tests, muscle damage markers and oxidative stress cytokines. For HBVc runners, HBV-DNA (hepatitis B virus-deoxyribonucleic acid) levels were also evaluated for virus reactivation. The results demonstrate a statistically significant increase in both immediate and 24-h post-race values for alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), compared with pre-race values. No statistically significant difference was observed between the 2 groups for the values of AST, LDH, CK, hs-CRP, IL-6 and TNF-α either before or after the race. There was also no statistically significant change in the levels of HBV-DNA in HBVc runners. These findings suggest that HBVc runners do not have higher risks of liver function impairment, muscle breakdown and inflammatory response compared to non-HBVc runners in such endurance races.


Assuntos
Portador Sadio , Hepatite B/virologia , Fígado/metabolismo , Corrida/fisiologia , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , Citocinas/metabolismo , DNA Viral/metabolismo , Feminino , Humanos , Inflamação/metabolismo , Fígado/virologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Resistência Física/fisiologia , Adulto Jovem
8.
Ann Rheum Dis ; 66(4): 517-21, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17012291

RESUMO

BACKGROUND: Tender points are a general measure of distress both in the community and in clinic subjects. It has been suggested that multiple tender points should be regarded as the early stages of somatisation of distress. Similarly, recent evidence suggests that chronic widespread pain (CWP) is one manifestation of the somatisation of distress. OBJECTIVE: Given that a high tender point count and CWP are clinical hallmarks of the fibromyalgia syndrome, it was hypothesised that in somatising subjects, a high tender point count or a low pain threshold would predict the development of CWP in the future. METHODS: In this population-based prospective study, 245 adults aged 25-65 years, free of CWP, were identified on the basis of a detailed questionnaire on pain and a psychosocial questionnaire comprising the Somatic Symptom Checklist and the Illness Behaviour subscale of the Illness Attitude Scales. These subjects took part in a pain threshold examination with a Fischer pressure algometer. Tender point counts were computed by including all areas with a pain threshold<4 kg/cm2. Individuals were followed up at 15 months, at which time 231 (93% of subjects still living at their baseline address) provided data on pain status, using the same instruments. RESULTS: At follow-up, 26 (11%) subjects developed new CWP. Although subjects with a low baseline pain threshold were not at increased risk of developing symptoms, a high tender point count, adjusted for age, sex, baseline pain status and other confounding factors, predicted the development of new CWP. CONCLUSION: Subjects free of CWP are at an increased risk of its development if they have a high tender point count. However, a low-pressure pain threshold does not predict the onset of symptoms. Data from this population-based prospective study suggest that a low pain threshold in subjects with CWP is likely to be a secondary phenomenon as a result of pain or associated distress rather than the antecedent of symptoms.


Assuntos
Fibromialgia/diagnóstico , Limiar da Dor , Transtornos Somatoformes/diagnóstico , Adulto , Idoso , Atitude Frente a Saúde , Doença Crônica , Inglaterra/epidemiologia , Métodos Epidemiológicos , Feminino , Fibromialgia/epidemiologia , Fibromialgia/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Prognóstico , Psicometria , Índice de Gravidade de Doença , Transtornos Somatoformes/epidemiologia , Transtornos Somatoformes/psicologia
9.
Rheumatology (Oxford) ; 46(4): 666-71, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17085772

RESUMO

OBJECTIVE: Chronic widespread pain (CWP) is strongly associated with psychosocial distress both in a clinical setting and in the community. The aim of this study was to determine the contribution of measures of psychosocial distress, health-seeking behaviour, sleep problems and traumatic life events to the development of new cases of CWP in the community. METHODS: In a population-based prospective study, 3171 adults aged 25-65 yrs free of CWP were followed-up 15 months later to identify those with new CWP. Baseline data were available on their scores from a number of psychological scales including Illness Attitude Scales (IAS), Somatic Symptom Checklist (SSC), Hospital Anxiety & Depression Scale, Sleep Problems Scale, and Life Events Inventory. RESULTS: 324 subjects [10%, 95% confidence interval (CI) 9.2, 11.3] developed new CWP at follow-up. After adjustment for age and sex, three factors independently predicted the development of CWP: scoring three or more on the SSC [odds ratio (OR) 1.8, 95% CI 1.1, 3.1], scoring eight or more on the Illness Behaviour subscale of the IAS (OR 3.3, 95% CI 2.3, 4.8), and nine or more on the Sleep Problem Scale (OR 2.7, 95% CI 1.6, 3.2). Subjects exposed to all three factors were at 12 times the odds of new CWP than those with low scores on all scales. CONCLUSION: Subjects are at substantial increased odds of developing CWP if they display features of somatization, health-seeking behaviour and poor sleep. Psychosocial distress has a strong aetiological influence on CWP.


Assuntos
Fibromialgia/psicologia , Transtornos Psicofisiológicos/psicologia , Adulto , Distribuição por Idade , Idoso , Doença Crônica , Métodos Epidemiológicos , Feminino , Fibromialgia/etiologia , Humanos , Acontecimentos que Mudam a Vida , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Aceitação pelo Paciente de Cuidados de Saúde , Escalas de Graduação Psiquiátrica , Psicometria , Transtornos do Sono-Vigília/psicologia
10.
Int J Obes (Lond) ; 30(5): 794-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16404404

RESUMO

OBJECTIVES: We aimed to assess the association between metabolic syndrome (MS) and hepatitis B/C virus infection using a large population-based study. DESIGN AND METHODS: A population-based cross-sectional study design was adopted with a total of 53,528 subjects being enrolled from the integrated multiple diseases screening program in Keelung, Taiwan. Evidence of past hepatitis B/C infection, acquired during childhood or as a young adult, was identified during the two-stage liver cancer screening part of the process. Information on biochemical markers and anthropometric measures related to MS, such as fasting blood sugar, triglyceride and high-density lipoprotein (HDL), abdominal circumference and blood pressure (BP), were collected routinely while screening for hypertension, type 2 diabetes, and hyperlipidemia. Logistic regression was used to estimate odds ratios and related 95% confidence intervals for the associations between MS and hepatitis B/C infection. RESULTS: High blood pressure (SBP > or = 135 mmHg or DBP > or = 85 mmHg) (adjusted odd ratio: 0.89 (0.83-0.94)) and high triglyceride (> or = 150 mg/dl) (adjusted odds ratio: 0.65 (0.60-0.69)) were, after adjusting for gender and age, inversely associated with being HBsAg positive (P<0.05). The likelihood of developing MS was lower in the HBsAg positive than the HBsAg negative (adjusted odds ratio: 0.84 (0.76-0.93)). A positive association between being anti-HCV positive and having low serum HDL (male <40 mg/dl, female <50 mg/dl) was also noted (adjusted odds ratio: 1.61 (1.37-1.88) after controlling for gender and age). High triglyceride was inversely associated with being anti-HCV positive (adjusted odds ratio: 0.63 (0.55-0.71). CONCLUSIONS: There is an inverse association between MS and hepatitis B virus infection whereas the association was heterogeneous for HCV infection with a positive association with abnormal serum HDL but an inverse association with hypertriglyceridemia.


Assuntos
Hepacivirus , Vírus da Hepatite B , Hepatite B/complicações , Hepatite C/complicações , Síndrome Metabólica/virologia , Adulto , Idoso , Métodos Epidemiológicos , Feminino , Antígenos de Superfície da Hepatite B/sangue , Hepatite Crônica/complicações , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Taiwan
11.
Epidemiol Infect ; 126(2): 291-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11349980

RESUMO

This study evaluated the roles of multiple factors in hepatitis C virus (HCV) infection, with emphasis on the modification of various individual characteristics on the risk associated with percutaneous exposure to blood. Serum samples taken from 4869 men in Taiwan within a cohort study were tested for HCV antibody. The overall positive rate of anti-HCV was 1.6%. In a logistic regression, factors positively associated with anti-HCV positivity were previous blood transfusion (odds ratio [OR] = 7.28: 95% confidence interval [CI] = 4.26-12.45), a history of surgery (OR = 2.06: 95% CI = 1 23-3.46), and lower educational levels (OR = 1.94; 95% CI = 1.14-3.32). The anti-HCV positive rate was significantly lower in hepatitis B surface antigen (HBsAg) carriers than in non-carriers (OR = 0.60; 95% CI = 0.37-0.95). Ageing, lower educational levels, O blood group, and Taiwanese ethnicity enhanced the likelihood of HCV infection through blood transfusion/surgery, whereasHBsAg status, cigarette smoking, and habitual alcohol drinking reduced it.


Assuntos
Anticorpos Anti-Hepatite C/sangue , Hepatite C/etiologia , Adulto , Idoso , Escolaridade , Governo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Fatores de Risco , Fumar/efeitos adversos , Taiwan , Reação Transfusional
12.
Immunity ; 15(6): 897-908, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11754812

RESUMO

Endosomal trafficking is an essential component of the CD1 pathway of lipid antigen presentation to T cells. We demonstrate that CD1d access to endosomal compartments is under dual regulation by an intrinsic tyrosine-based motif, which governs intense recycling between the plasma membrane and the endosome, and by the invariant chain, with which CD1d associates in the endoplasmic reticulum. Both pathways independently enhance antigen presentation to V(alpha)14(+) NKT cells, the main subset of CD1d-restricted T cells. These results reveal the complexity of CD1d trafficking and suggest that the invariant chain was a component of ancestral antigen presentation pathways prior to the evolution of MHC and CD1.


Assuntos
Apresentação de Antígeno/fisiologia , Antígenos CD1/metabolismo , Antígenos de Diferenciação de Linfócitos B/fisiologia , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Antígenos de Histocompatibilidade Classe II/fisiologia , Motivos de Aminoácidos , Animais , Antígenos CD1/química , Antígenos CD1/genética , Antígenos CD1d , Antígenos de Superfície/metabolismo , Linfócitos B/metabolismo , Biotinilação , Membrana Celular/metabolismo , Células Cultivadas/metabolismo , Células Dendríticas/metabolismo , Evolução Molecular , Fibroblastos/metabolismo , Glicosilação , Hibridomas/metabolismo , Cinética , Linfoma de Células B/patologia , Lisossomos/metabolismo , Camundongos , Microscopia de Fluorescência , Ligação Proteica , Processamento de Proteína Pós-Traducional , Transporte Proteico , Proteínas Recombinantes de Fusão/metabolismo , Frações Subcelulares/metabolismo , Transfecção , Células Tumorais Cultivadas/metabolismo , Tirosina/química
13.
Br J Cancer ; 80(3-4): 598-603, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10408872

RESUMO

Cigarette smoking has been associated with increased risk of hepatocellular carcinoma (HCC) in some epidemiological studies. Cytochrome P450 1A1 (CYP1A1) is involved in the biotransformation of tobacco-derived polycyclic aromatic hydrocarbons (PAHs) into carcinogenic metabolites. The aim of this study was to determine whether CYP1A1 polymorphisms were related to HCC risk among chronic hepatitis B virus (HBV) carriers. Genotypic variants of CYP1A1 were determined using polymerase chain reaction in 81 incident cases of HCC and 409 controls nested in a cohort study of 4841 male chronic HBV carriers. No overall association between CYP1A1 genotypes and HCC was observed. The presence of the Mspl (odds ratio (OR) 3.15, P = 0.0196) or Ile-Val (OR 1.99, P = 0.0855) variant allele of CYP1A1 increased HCC risk among smokers, but posed no increased risk among non-smokers. The smoking-related HCC risk was most pronounced among those who had a susceptible allele of the CYP1A1 and a deficient genotype of glutathione S-transferase M1, which detoxifies PAH electrophilic metabolites produced by CYP1A1. In the absence of the Ile-Val variant allele, the Mspl polymorphism was still associated with smoking-related HCC. This study suggests that tobacco-derived PAHs play a role in HCC risk among chronic HBV carriers, and CYP1A1 polymorphism is an important modulator of the hepatocarcinogenic effect of PAHs. The Mspl and Ile-Val polymorphisms of CYP1A1 may have different mechanisms for increasing susceptibility to smoking-related HCC.


Assuntos
Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Portador Sadio/enzimologia , Citocromo P-450 CYP1A1/genética , Hepatite B Crônica/complicações , Hepatite B Crônica/enzimologia , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Adulto , Idoso , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/virologia , Portador Sadio/epidemiologia , Portador Sadio/virologia , Estudos de Casos e Controles , Citocromo P-450 CYP1A1/metabolismo , Predisposição Genética para Doença , Genótipo , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B , Hepatite B Crônica/sangue , Hepatite B Crônica/genética , Humanos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores de Risco , Fumar/efeitos adversos
14.
Am J Epidemiol ; 149(7): 621-9, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10192309

RESUMO

This study was conducted to assess the role of carotenoid and glutathione S-transferase (GST) M1 and T1 genetic polymorphisms in the development of hepatocellular carcinoma (HCC). A total of 84 incident cases of HCC and 375 matched controls selected from a cohort of 7,342 men (4,841 chronic hepatitis B carriers and 2,501 noncarriers) who were recruited between 1988 and 1992 in Taiwan were studied. Neither GST M1/T1 polymorphisms nor plasma levels of various carotenoids were independently associated with HCC, but they modulated smoking- and/or drinking-related HCC risk. Cumulative exposure to tobacco smoke significantly increased HCC risk in a dose-dependent manner among subjects with low plasma beta-carotene levels (p for trend = 0.047) but not among those with high levels. A statistically significant effect of habitual alcohol drinking on HCC risk was observed only for those with low plasma levels of beta-carotene, alpha-carotene, or lycopene and for GST M1 null subjects. There was evidence suggesting an interaction between the GST M1/T1 genotype and certain carotenoids in HCC associated with smoking and drinking. The strongest effect of smoking and drinking was noted among GST M1 null subjects with low plasma levels of beta-carotene (smoking: adjusted odds ratio (OR) = 3.54, 95% confidence interval (CI) 1.06-11.83; drinking: OR = 8.28, 95% CI 2.40-28.61).


Assuntos
Carcinoma Hepatocelular/sangue , Carotenoides/genética , Glutationa Transferase/genética , Neoplasias Hepáticas/sangue , Polimorfismo Genético , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/genética , Carotenoides/sangue , DNA de Neoplasias/análise , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Glutationa Transferase/sangue , Humanos , Incidência , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fumar/efeitos adversos , Taiwan/epidemiologia
15.
Hepatology ; 29(3): 697-702, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10051470

RESUMO

This study evaluated whether the codon 72 p53 polymorphism was related to hepatocellular carcinoma (HCC). Genotypes of p53 were determined in 80 incident cases of HCC and 328 controls nested in a cohort study of 4,841 male chronic hepatitis B carriers. No overall increase in HCC risk with the Pro variant allele of the p53 polymorphism was apparent. However, there were synergistic effects on HCC development for the Pro allele with chronic liver disease and family history of HCC in first-degree relatives. Compared with subjects without the Pro allele and chronic liver disease, the increase in HCC risk associated with chronic liver disease among those without the Pro allele was only threefold. Subjects with both chronic liver disease and the Pro allele were at an increased risk of 7.60 (95% CI = 2.28-25.31). When subjects without family history of HCC and the Pro allele were considered as the reference group, there was no apparent increased risk of HCC for those without the Pro allele who had family history of HCC. Among those with both factors, there was a significantly increased risk of 3.29 (95% CI = 1.10-9.85). Both cigarette smoking and glutathione S-transferase M1 genotype modified the risk of HCC associated with the p53 polymorphism. Significantly increased risk associated with the p53 genotype was observed only among smokers who were glutathione S-transferase-null (Pro/Pro vs. Arg/Arg: odds ratio = 6.46; 95% CI = 1.55-26.94). The p53 polymorphism also interacted with the cytochrome P450 1A1 and carotenoid levels in smoking-related hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Predisposição Genética para Doença/genética , Neoplasias Hepáticas/genética , Polimorfismo Genético/fisiologia , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Carcinoma Hepatocelular/etiologia , Portador Sadio , Estudos de Casos e Controles , Doença Crônica , Hepatite B Crônica/complicações , Humanos , Hepatopatias/complicações , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos
16.
Semin Immunol ; 10(5): 391-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9799714

RESUMO

In the past few years, several studies have unravelled a novel pathway of antigen presentation to T cells of the mammalian immune system. The antigens are presented by CD1, which appears to have evolved to present glycolipid antigens to alphabeta T cells. CD1-restricted T cells are frequently autoreactive, and can promptly release key regulatory cytokines such as IL-4 and IFN-gamma. They have been implicated in a variety of autoimmune diseases including type I diabetes and lupus, in intracellular bacterial infections, and in tumor rejection. They are likely to be involved at the early, innate phase of these immune responses, providing a unique model to study the interface between the innate and adaptive immune systems.


Assuntos
Apresentação de Antígeno , Antígenos CD1/fisiologia , Imunidade , Animais , Autoimunidade , Humanos , Neoplasias/imunologia , Linfócitos T/imunologia
17.
J Hepatol ; 27(2): 320-30, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9288607

RESUMO

BACKGROUND/AIMS: Aflatoxins (AFs) are established hepatic carcinogens in several animal species. This study was performed to establish whether aflatoxin exposure may affect the risk of developing hepatocellular carcinoma in chronic hepatitis B virus carriers. METHODS: Urinary AF metabolites were measured for 43 HCC cases and 86 matched controls nested in a cohort of 7342 men in Taiwan. Thirty hepatocellular carcinoma cases and 63 controls were also tested for AFB1-albumin adducts. RESULTS: There was a dose-response relationship between urinary AFM1 levels and risk of hepatocellular carcinoma in chronic hepatitis B virus carriers. Comparing the highest with the lowest tertile of urinary AFM1 levels, the multivariate-adjusted odds ratio (OR) was 6.0 (95% confidence interval (CI) = 1.2-29.0). The hepatocellular carcinoma risk associated with AFB1 exposure was more striking among the hepatitis B virus carriers with detectable AFB1-N7-guanine adducts in urine. Compared with chronic hepatitis B virus carriers who were negative for AFB1-albumin adducts and urinary AFB1-N7-guanine, no elevated risk was observed for those who were positive for either marker. But an extremely high risk of hepatocellular carcinoma among those having both markers was found (OR = 10.0, 95% CI = 1.6-60.9). The proportion of AFB1 converted to AFM1 decreased with the progress of liver disease, whereas the formation of AFP1 increased. The difference in patterns of AFB1 metabolite formation was an independent risk factor for hepatocellular carcinoma after adjustment for total AFB1 excretion. There was a synergistic interaction between glutathione S-transferase M1 genotype and AFB1 exposure in hepatocellular carcinoma risk. CONCLUSIONS: AFB1 intake and expression of enzymes involved in AFB1 activation/detoxification may play an important role in hepatitis B virus-related hepatocarcinogenesis.


Assuntos
Aflatoxinas/metabolismo , Carcinoma Hepatocelular/metabolismo , Portador Sadio , Adutos de DNA/biossíntese , Hepatite B/complicações , Neoplasias Hepáticas/metabolismo , Adulto , Aflatoxinas/genética , Idoso , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/genética , Doença Crônica , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Fatores de Risco
18.
Planta Med ; 63(6): 571-2, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17252381

RESUMO

Two hydroperoxysterols 24-hydroperoxy-24-vinyl-cholesterol (1) and 29-hydroperoxystigmasta-5,24(28)-dien-3beta-ol (2), and fucosterol (3) were isolated from the brown alga Turbinaria ornata (Sargassaceae). Hydroperoxide 2 is a new natural compound and was converted into 29-hydroxystigmasta-5,24 (28)-dien-3beta-ol (4) by reaction with LAH. Sterols 1, 2, and 4 exhibited cytotoxicity against various cancer cell lines.

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