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1.
Hepatol Int ; 17(3): 584-594, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36737504

RESUMO

BACKGROUND AND AIMS: Epigenetic modifications are associated with hepatic fat accumulation and non-alcoholic fatty liver disease (NAFLD). However, few epigenetic modifications directly implicated in such processes have been identified during adolescence, a critical developmental window where physiological changes could influence future disease trajectory. To investigate the association between DNA methylation and NAFLD in adolescence, we undertook discovery and validation of novel methylation marks, alongside replication of previously reported marks. APPROACH AND RESULTS: We performed a DNA methylation epigenome-wide association study (EWAS) on DNA from whole blood from 707 Raine Study adolescents phenotyped for steatosis score and NAFLD by ultrasound at age 17. Next, we performed pyrosequencing validation of loci within the most 100 strongly associated differentially methylated CpG sites (dmCpGs) for which ≥ 2 probes per gene remained significant across four statistical models with a nominal p value < 0.007. EWAS identified dmCpGs related to three genes (ANK1, MIR10a, PTPRN2) that met our criteria for pyrosequencing. Of the dmCpGs and surrounding loci that were pyrosequenced (ANK1 n = 6, MIR10a n = 7, PTPRN2 n = 3), three dmCpGs in ANK1 and two in MIR10a were significantly associated with NAFLD in adolescence. After adjustment for waist circumference only dmCpGs in ANK1 remained significant. These ANK1 CpGs were also associated with γ-glutamyl transferase and alanine aminotransferase concentrations. Three of twenty-two differentially methylated dmCpGs previously associated with adult NAFLD were associated with NAFLD in adolescence (all adjusted p < 2.3 × 10-3). CONCLUSIONS: We identified novel DNA methylation loci associated with NAFLD and serum liver biochemistry markers during adolescence, implicating putative dmCpG/gene regulatory pathways and providing insights for future mechanistic studies.


Assuntos
Metilação de DNA , Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Adolescente , Hepatopatia Gordurosa não Alcoólica/genética , Epigênese Genética , DNA , Biomarcadores
2.
Hum Reprod ; 37(8): 1880-1895, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35640037

RESUMO

STUDY QUESTION: Is the cardiometabolic health of adolescents conceived through ART worse than that of their counterparts conceived without ART? SUMMARY ANSWER: The majority of cardiometabolic and vascular health parameters of adolescents conceived through ART are similar or more favourable, than those of their counterparts of similar age and conceived without ART. WHAT IS KNOWN ALREADY: It has been proposed that the cardiometabolic health of offspring conceived with ART may be unfavourable compared to that of their counterparts conceived without ART. The literature pertaining to cardiometabolic health of offspring conceived after ART is contradictory, but generally suggests unfavourable cardiometabolic health parameters, such as an increase in blood pressure (BP), vascular dysfunction and adiposity, as well as unfavourable glucose and lipid profiles. With over 8 million children and adults born through ART worldwide, it is important to investigate whether these early signs of adverse cardiometabolic differences persist into adolescence and beyond. STUDY DESIGN, SIZE, DURATION: The Growing Up Healthy Study (GUHS) is a prospective cohort study that recruited 303 adolescents and young adults conceived after ART (aged 13-21 years) and born between 1991 and 2001 in Western Australia. Their health parameters, including cardiometabolic factors, were assessed and compared with counterparts from the Raine Study Generation 2 (Gen2). The 2868 Gen2 participants were born 1989-1992 and are representative of the Western Australian adolescent population. At ∼17 years of age (2013-2017), 163 GUHS participants replicated assessments previously completed by Gen2 at a similar age. PARTICIPANTS/MATERIALS, SETTING, METHODS: Cardiometabolic parameters were compared between a total of 163 GUHS and 1457 Gen2 adolescents. Separate male (GUHS n = 81, Gen2 n = 735) and female (GUHS n = 82, Gen2 n = 722) analyses were conducted. Assessments consisted of a detailed questionnaire including health, lifestyle and demographic parameters, anthropometric assessments (height, weight, BMI, waist circumference and skinfold thickness), fasting serum biochemistry, arterial stiffness and BP (assessed using applanation tonometry). Abdominal ultrasonography was used to assess the presence and severity of hepatic steatosis, and thickness of abdominal fat compartments. Non-alcoholic fatty liver disease (NAFLD) was diagnosed if there was sonographic fatty liver in the absence of significant alcohol consumption. Chi2, Fisher's exact and Mann-Whitney U tests, performed in SPSS V25, examined cohort differences and generalized estimating equations adjusted for the following covariates: singleton vs non-singleton pregnancy, birthweight (z-score), gestational age, BMI, smoking, alcohol consumption in the past 6 months and parent cardiovascular status. Arterial stiffness measures and waist circumference were additionally adjusted for height, and female analyses were additionally adjusted for use of oral contraceptives in the preceding 6 months. MAIN RESULTS AND THE ROLE OF CHANCE: In adjusted analyses, GUHS females had a lower BMI (22.1 vs 23.3 kg/m2, P = 0.014), and thinner skinfolds (triceps, subscapular, mid-abdominal; 16.9 vs 18.7 mm, P = 0.021, 13.4 vs 15.0 mm, P = 0.027, 19.7 vs 23.2 mm, P < 0.001, respectively), whereas males were not significantly different. Waist circumference was lower in GUHS adolescents (males: 78.1 vs 81.3 cm, P = 0.008, females: 76.7 vs 83.3 cm, P = 0.007). There were no significant differences between the two groups in glucose, insulin, homeostatic model assessment for insulin resistance, low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol (non-HDL-C), total cholesterol (TC), alanine aminotransferase and high-sensitivity C-reactive protein in both sexes. In females, serum triglycerides were lower in GUHS adolescents (1.0 vs 1.2 mmol/l, P = 0.029). GUHS males had higher serum HDL-C (1.1 vs 1.0 mmol/l, P = 0.004) and a lower TC/HDL-C ratio (3.2 vs 3.6, P = 0.036). There were no significant differences in the prevalence of NAFLD or steatosis severity scores between the cohorts in males and females. GUHS females had less subcutaneous adipose tissue (9.4 vs 17.9 mm, P < 0.001), whereas GUHS males had greater visceral adipose thickness (44.7 vs 36.3 mm, P < 0.001). There was no significant difference in pre-peritoneal adipose thickness. Pulse wave velocity was lower in GUHS males (5.8 vs 6.3 m/s, P < 0.001) and heart rate corrected augmentation index was lower in GUHS females (-8.4 vs -2.7%, P = 0.048). There were no significant differences in BP or heart rate in males or females between the two groups. LIMITATIONS, REASONS FOR CAUTION: Despite the substantial study size and the unique study design of the ART cohort, we were unable to differentiate between different types of ART, due to the low number of ICSI cycles (e.g. IVF vs ICSI), draw definite conclusions, or relate the outcomes to the cause of infertility. Considering the differences in time points when both cohorts were studied, external factors could have changed, which could not be accounted for. Given the observational nature of this study, causation cannot be proven. WIDER IMPLICATIONS OF THE FINDINGS: Contrary to our hypothesis and previous findings focussing mainly on childhood, this study reports mostly similar or favourable cardiometabolic markers in adolescents conceived with ART compared to those conceived without ART. The greater visceral adipose thickness, particularly present in males, requires further investigation. While these findings are generally reassuring, future well-designed and appropriately powered studies are required to definitively address the issue of cardiometabolic health in ART adults. STUDY FUNDING/COMPETING INTEREST(S): This project was supported by NHMRC project grant number 1042269 and R.J.H. received education grant funding support from Ferring Pharmaceuticals. R.J.H. is the Medical Director of Fertility Specialists of Western Australia and a shareholder in Western IVF. He has received educational sponsorship from MSD, Merck-Serono and Ferring Pharmaceuticals. P.B. is the Scientific Director of Concept Fertility Centre, Subiaco, Western Australia. J.L.Y. is the Medical Director of PIVET Medical Centre, Perth, Western Australia. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Doenças Cardiovasculares , Hepatopatia Gordurosa não Alcoólica , Adolescente , Austrália , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Criança , Estudos de Coortes , Feminino , Fertilização in vitro/métodos , Glucose , Humanos , Masculino , Gravidez , Estudos Prospectivos , Análise de Onda de Pulso , Adulto Jovem
3.
Mar Pollut Bull ; 156: 111150, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32510354

RESUMO

For much of the 20th century, the Mersey in North West England was one of the worst polluted estuaries in Europe. Water from a range of polluting industries plus domestic sewage was discharged into the Mersey Catchment and Estuary. Recovery came through a concerted clean-up campaign and tightening environmental regulations, partly driven by European Commission Directives, coupled with de-industrialisation from the 1970s onward. Recovery of oxygen levels in the Estuary led to the return of a productive ecosystem. This led to conservation designations, but also concerns about transfer of pollutants to higher trophic levels in fish, birds and humans. As part of urban renewal, ecosystems in disused dock basins were restored using mussel biofiltration and artificial de-stratification, facilitating commercial redevelopment and creation of a tourist destination. The degradation and recovery of the Mersey from peak-pollution in the mid-20th century is put in the context of wider environmental change and briefly compared to other systems to develop a hysteresis model of degradation and recovery, often to novel ecosystems.


Assuntos
Estuários , Poluentes Químicos da Água/análise , Animais , Ecossistema , Inglaterra , Monitoramento Ambiental , Europa (Continente) , Humanos , Esgotos
4.
Osteoporos Int ; 30(10): 2065-2072, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31342138

RESUMO

One year of calcium supplementation in older women led to modest reductions in total osteocalcin and undercarboxylated osteocalcin (ucOC), with no changes in muscle or fat mass, or glycated haemoglobin. Future studies should explore whether treatments with more profound effects of suppressing ucOC may lead to impaired glycaemic control. INTRODUCTION: Total osteocalcin (TOC) is a marker of bone turnover, while its undercarboxylated form has beneficial effects on glucose metabolism in mice. This post hoc analysis of a randomised double-blind, placebo-controlled trial examined whether 1 year of calcium supplementation affected circulating TOC, undercarboxylated osteocalcin (ucOC) or glycated haemoglobin (HbA1c) in 1368 older community-dwelling women (mean age 75.2 ± 2.7 years). METHODS: Women enrolled in the Calcium Intake Fracture Outcome Study trial (1998-2003) were supplemented with 1.2 g/d of elemental calcium (in the form of calcium carbonate) or placebo. Circulating TOC, ucOC and HbA1c was measured at 1 year (1999). RESULTS: After 1 year of calcium supplementation, TOC and ucOC levels were 17% and 22% lower compared with placebo (mean 22.7 ± 9.1 vs. 27.3 ± 10.9 µg/L and 11.1 ± 4.9 vs. 13.0 ± 5.7 µg/L, both P < 0.001). Carboxylated osteocalcin/ucOC was 6% lower after calcium supplementation (P < 0.05). Despite this, no differences in HbA1c were observed (calcium, 5.2 ± 0.6 vs. placebo, 5.3 ± 0.8%; P = 0.08). Calcium supplementation did not affect BMI, whole body lean or fat mass. In exploratory analyses, total calcium (dietary and supplemental) was inversely related to TOC and ucOC, indicating calcium intake is an important dietary determinant of osteocalcin levels. CONCLUSION: One year of calcium supplementation in older women led to modest reductions in TOC and ucOC, with no changes in muscle or fat mass, or HbA1c. Future studies should explore whether treatments with more profound effects of suppressing ucOC may lead to impaired glycaemic control.


Assuntos
Cálcio/farmacologia , Suplementos Nutricionais , Hemoglobinas Glicadas/metabolismo , Osteocalcina/sangue , Tecido Adiposo/efeitos dos fármacos , Idoso , Biomarcadores/sangue , Composição Corporal/efeitos dos fármacos , Índice de Massa Corporal , Cálcio/administração & dosagem , Cálcio da Dieta/farmacologia , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos
5.
Hum Reprod ; 34(3): 389-402, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30576537

RESUMO

STUDY QUESTION: Are early signs of metabolic disorder in late adolescence associated with features of impaired testicular function many years before the majority seek parenthood? SUMMARY ANSWER: Adolescents with features of metabolic disorder at 17 years, or insulin resistance (IR) at 20 years of age, show impaired testicular function and altered hormone levels compared to those without metabolic disorder. WHAT IS KNOWN ALREADY: Controversial evidence suggests a recent decline in sperm production potentially linked to environmental influences, but its cause remains unclear. Concomitant increases in obesity and diabetes suggest that lifestyle factors may contribute to this decline in testicular function. Although obesity has been associated with adverse testicular function in some studies, it remains unclear whether poor testicular function merely reflects, or causes, poor metabolic health. If metabolic disorder were present in adolescence, prior to the onset of obesity, this may suggest that metabolic disorder maybe a precursor of impaired testicular function. STUDY DESIGN, SIZE, DURATION: The Western Australian Pregnancy Cohort (Raine) Study is a longitudinal study of children born in 1989-1991 who have undergone detailed physical assessments since birth (1454 male infants born). At 17 years of age, 490 boys underwent a hepatic ultrasound examination, serum cytokine assessment (n = 520) and a metabolic assessment (n = 544). A further metabolic assessment was performed at 20 years (n = 608). Testicular assessment was performed at 20 years; 609 had reproductive hormones measured, 404 underwent a testicular ultrasound and 365 produced a semen sample. PARTICIPANTS/MATERIALS, SETTING, METHODS: Testicular volume was estimated by ultrasonography, and semen analysis was performed according to World Health Organization guidelines. Concentrations of LH, FSH and inhibin B (inhB) in serum were measured by immunoassay and total testosterone by liquid chromatography-mass spectrometry.At 17 years of age, a liver ultrasound examination was performed to determine the presence of non-alcoholic fatty liver disease (NAFLD), and serum analysed for the cytokines interleukin-18 and soluble tumour necrosis factor receptor 1 and 2 (sTNFR1, sTNFR2).At 17 and 20 years of age, fasting blood samples were analysed for serum liver enzymes, insulin, glucose, triglycerides (TG), total cholesterol, high density lipoprotein and low density lipoprotein cholesterol, high sensitivity C-reactive protein and uric acid. The homoeostatic model assessment (HOMA) was calculated and approximated IR was defined by a HOMA >4. Anthropometric data was collected and dual energy X-ray absorptiometry measurement performed for lean and total fat mass. As at this young age the prevalence of metabolic syndrome was expected to be low, a two-step cluster analysis was used using waist circumference, TGs, insulin, and systolic blood pressure to derive a distinct high-risk group with features consistent with the metabolic syndrome and increased cardiometabolic risk. MAIN RESULTS AND THE ROLE OF CHANCE: Men at age 17 years with increased cardiometabolic risk had lower concentrations of serum testosterone (medians: 4.0 versus 4.9 ng/mL) and inhB (193.2 versus 221.9 pg/mL) (P < 0.001 for both) compared to those within the low risk metabolic cluster. Men with ultrasound evidence of NAFLD (n = 45, 9.8%) had reduced total sperm output (medians: 68.0 versus 126.00 million, P = 0.044), testosterone (4.0 versus 4.7 ng/mL, P = 0.005) and inhB (209.1 versus 218.4 pg/mL, P = 0.032) compared to men without NAFLD.Men with higher concentrations of sTNFR1 at 17 years of age had a lower sperm output and serum concentration of inhB, with an increase in LH and FSH (all P < 0.05 after adjustment for age, BMI, abstinence and a history of cryptorchidism, varicocele, cigarette smoking, alcohol and drug use), compared to those without an elevated sTNFR1. Multivariable regression analysis, adjusting for confounders, demonstrated that men in the high-risk metabolic cluster at 20 years had a lower serum testosterone and inhB (P = 0.003 and P = 0.001, respectively). A HOMA-IR > 4 was associated with a lower serum testosterone (P = <0.001) and inhB (P = 0.010) and an increase in serum FSH (P = 0.015). LIMITATIONS, REASONS FOR CAUTION: This study is limited by the sample size and multiple comparisons, and causality cannot be proven from an observational study. Due to a 3-year interval between some metabolic assessments and assessment of testicular function, we cannot exclude the introduction of a bias into the study, as some of the participants and their testicular function will not have been fully mature at the 17-year assessment. WIDER IMPLICATIONS OF THE FINDINGS: Irrespective of a proven causation, our study findings are important in that a significant minority of the men, prior to seeking parenthood, presented co-existent features of metabolic disorder and signs of testicular impairment. Of particular note is that the presence of NAFLD at 17 years of age, although only present in a minority of men, was associated with an almost 50% reduction in sperm output at 20 years of age, and that the presence of IR at 20 years was associated with a 20% reduction in testicular volume. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by Australian NHMRC (Grant Numbers 634457, 35351417 and 403981) and received support from the Raine Medical Research Foundation, The Telethon Kids Institute, University of Western Australia, Women and Infants Research Foundation, Curtin University and Edith Cowan University. D.A.D., J.E.D., N.M., L.A.A., R.-C.H., T.A.M., J.K.O., L.J.B. have nothing to declare. R.J.H. is Medical Director of Fertility Specialists of Western Australia, has equity interests in Western IVF, and has received grant support from MSD, Merck-Serono and Ferring Pharmaceuticals. RMcL has equity interests in the Monash IVF Group. R.J.N. has equity interests in FertilitySA, and has received grant support from Merck Serono and Ferring Pharmaceuticals. D.J.H. has received institutional grant funding (but no personal income) for investigator-initiated testosterone pharmacology studies from Lawley and Besins Healthcare and has provided expert testimony to anti-doping tribunals and for testosterone litigation.This abstract was awarded the Fertility Society of Australia clinical exchange award for the oral presentation at ESHRE, Barcelona, in 2018.


Assuntos
Resistência à Insulina , Síndrome Metabólica/fisiopatologia , Testículo/fisiopatologia , Adolescente , Análise por Conglomerados , Citocinas/sangue , Complicações do Diabetes , Hormônio Foliculoestimulante/sangue , Humanos , Inibinas/sangue , Fígado/diagnóstico por imagem , Estudos Longitudinais , Hormônio Luteinizante/sangue , Masculino , Síndrome Metabólica/sangue , Obesidade/complicações , Doenças Testiculares/sangue , Doenças Testiculares/fisiopatologia , Testículo/diagnóstico por imagem , Testosterona/sangue , Austrália Ocidental , Adulto Jovem
6.
Aliment Pharmacol Ther ; 45(2): 332-344, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27862096

RESUMO

BACKGROUND: Several recent studies have shown a strong association between non-alcoholic steatohepatitis (NASH) and chronic kidney disease. AIM: To examine the relationship between changes in liver histology and renal function in patients with NASH. METHODS: The present analysis represents a post hoc analysis of a recently published trial that included 261 patients with NASH who were treated with lifestyle modifications during 52 weeks. Kidney function was evaluated through Chronic Kidney Disease Epidemiology Collaboration estimated glomerular filtration rates (eGFR, mL/min/1.73 m2 ) overtime. We explored correlations between the kidney function and improvement in histological outcomes at 52 weeks. RESULTS: Interestingly, a one-stage reduction in fibrosis (r = 0.20, P < 0.01) and resolution of NASH (r = 0.17, P < 0.01) were significantly correlated with an improvement in the kidney function. The eGFR values significantly increased in patients with fibrosis improvement (+7.6 ± 6.5 mL/min/1.73 m2 ), compared to those without fibrosis improvement (-1.98 ± 6.4 mL/min/1.73 m2 ) (P < 0.01) at end of treatment (EOT). Likewise, NASH resolution was associated with an increase in eGFR compared with patients without NASH resolution (2.32 ± 7.8 mL/min/1.73 m2 vs. -1.04 ± 5.9 mL/min/1.73 m2 , P = 0.04) at EOT. After controlling for the confounders, the association between fibrosis improvement, NASH resolution and eGFR change remained significant (P < 0.05 for both). CONCLUSIONS: Improvement in liver histology due to lifestyle modification is independently associated with improved kidney function in NASH. As new drugs for NASH emerge, studies should address whether improvement in histology in response to pharmacotherapies yield the same improvement in kidney function as weight loss.


Assuntos
Rim/fisiologia , Estilo de Vida , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica , Adulto , Feminino , Taxa de Filtração Glomerular , Humanos , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia
7.
Intern Med J ; 46(7): 863, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27405900
8.
Intern Med J ; 46(1): 63-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26477784

RESUMO

BACKGROUND: Vascular disease is a common cause of death in patients with chronic hepatitis C (CHC) infection; however, the association between CHC and atherosclerosis is unclear. AIMS: To determine whether patients with CHC have increased subclinical vascular disease and whether genotype or antiviral treatment modifies this risk. METHODS: Fifty CHC patients and 22 age-matched and sex-matched healthy controls underwent clinical and biochemical assessment for vascular risk factors. In addition, vascular risk was assessed by measuring arterial stiffness (aortic augmentation index and carotid-femoral pulse wave velocity (PWV)), endothelial dysfunction (brachial artery flow-mediated dilatation (FMD) and dilatation post-glycerol trinitrate administration) and carotid intima-media thickness (CIMT). Assessment was repeated in subset of CHC patients (n = 12) undergoing antiviral treatment 18 months after initiation of treatment. RESULTS: Baseline vascular risk factors and measures of arterial stiffness, endothelial dysfunction and CIMT were not different between cases and controls (P > 0.2 for all). Genotype 1 CHC patients had greater endothelial dysfunction with lower FMD (8.2 ± 3.5% vs 10.9 ± 5.2%, P = 0.03) and higher right CIMT (0.6 ± 0.1 mm vs 0.5 ± 0.07 mm, P = 0.04) compared with non-genotype 1. Patients who achieved sustained virological response (7/12) showed significant improvement in insulin resistance (homeostasis model of assessment of insulin resistance 2.3 ± 1.2 vs 1.8 ± 0.8, P = 0.02) and arterial stiffness (PWV 7.4 ± 1.1 m/s vs 6.5 ± 0.6 m/s, P = 0.04). CONCLUSIONS: Subclinical vascular disease is not greater in CHC subjects compared with controls. However, among CHC subjects, genotype 1 infection is associated with greater endothelial dysfunction and increased carotid-intima medial thickness compared with non-genotype 1 infection. Successful viral eradication may improve insulin resistance and arterial stiffness.


Assuntos
Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Espessura Intima-Media Carotídea , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/epidemiologia , Adulto , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Rigidez Vascular/fisiologia
9.
Chem Commun (Camb) ; 51(88): 15898-901, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26391199

RESUMO

Quantitative cysteine-independent ligation of a Gd(3+) tag to genetically encoded p-azido-L-phenylalanine via Cu(I)-catalyzed click chemistry is shown to deliver an exceptionally powerful tool for Gd(3+)-Gd(3+) distance measurements by double electron-electron resonance (DEER) experiments, as the position of the Gd(3+) ion relative to the protein can be predicted with high accuracy.


Assuntos
Proteínas de Transporte/síntese química , Espectroscopia de Ressonância de Spin Eletrônica , Escherichia coli/química , Gadolínio , Glutamatos/química , Fenilalanina/análogos & derivados , Estrutura Terciária de Proteína , Sequência de Aminoácidos , Azidas/química , Proteínas de Transporte/química , Química Click , Mutagênese Sítio-Dirigida , Fenilalanina/química , Fenilalanina/genética , Marcadores de Spin
10.
Nutr Metab Cardiovasc Dis ; 25(4): 388-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25638597

RESUMO

BACKGROUND AND AIMS: Protein consumption has been associated with cardio-metabolic benefits, including weight loss and improved insulin sensitivity, and may have potential benefits for individuals with fatty liver disease (FLD). We investigated the effect of increasing dietary protein intake from whey relative to carbohydrate on hepatic steatosis. METHODS AND RESULTS: A two-year randomized, double-blind, placebo-controlled trial of 30 g/day whey protein-supplemented beverage (protein) or an energy-matched low-protein high-carbohydrate beverage (control) for cardio-metabolic and bone health in 219 healthy elderly women, recruited from the Western Australian general population. Hepatic steatosis was quantified using computed tomographic liver-to-spleen (L/S) ratio. FLD was defined as liver-to-spleen difference <10 Hounsfield units. At baseline, FLD prevalence was 11.4%. Control and protein groups were similar in body mass index (BMI), insulin resistance, L/S ratio and FLD prevalence at baseline. At two-years, dietary protein increased by 20 g in the protein, but not the control, group. Total energy intake and physical activity remained similar between groups. At two-years, BMI and FLD prevalence increased in both groups, with no between group differences. L/S ratio increased in control, but not protein, group at two-years, with no between group differences. In a within group comparison, change in BMI correlated with changes in L/S ratio in control (r = 0.37, P = 0.0007), but not with protein group (r = 0.04, P = 0.73). CONCLUSION: Increasing dietary protein intake from whey relative to carbohydrate does not reduce weight, hepatic steatosis or the prevalence of FLD in elderly women. However, it may prevent worsening of hepatic steatosis associated with weight gain. CLINICAL TRIALS REGISTRATION: Australian New Zealand Clinical Trials Registry (Registration no. ACTRN012607000163404).


Assuntos
Dieta , Fígado Gorduroso/prevenção & controle , Aumento de Peso , Proteínas do Soro do Leite/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Índice de Massa Corporal , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Método Duplo-Cego , Ingestão de Energia , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Atividade Motora , Nova Zelândia , Triglicerídeos/sangue , Circunferência da Cintura
11.
Intern Med J ; 45(1): 48-54, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25371273

RESUMO

BACKGROUND AND AIMS: Rates of long-term clinical outcomes of chronic hepatitis C in patients with none, mild or severe liver fibrosis are required to determine benefits of anti-viral therapies. This study evaluated long-term outcomes for chronic hepatitis C stratified by all Metavir fibrosis stages. METHODS: Clinical outcomes were determined using population-based data linkage methodology for 880 hepatitis C patients who had a liver biopsy performed from 1992 to 2012. RESULTS: During 9386 person-years of follow up, 28 patients developed hepatocellular carcinoma, 58 developed liver decompensation and 122 died or underwent liver transplantation. There was no significant difference in liver-related death for those with F0-F2 with an 18-year survival probability >94%. Hazard ratio of liver-related death for F3 compared with F0-F2 was 4.24 (P = 0.003), with no significant difference in the first 13-year follow up. The 15-year decompensation-free survival for F0, F1 and F2 was 100%, 96% and 94% respectively and for hepatocellular carcinoma-free survival was 100%, 99% and 98%. Hazard ratio of liver complication (hepatocellular carcinoma or decompensation)-free survival for F3 compared with F0-F2 was 3.22 (P = 0.001), with no significant difference during the first 7-year follow up. F4 had significantly higher risk of liver-related death, decompensation and hepatocellular carcinoma than F3 (P < 0.001). CONCLUSIONS: Chronic hepatitis C patients with F2 or less had few liver complications after 15 years. For F3 patients, the significant increase in liver-related death occurred after 13 years and for liver complications after 7 years.


Assuntos
Carcinoma Hepatocelular/etiologia , Hepatite C Crônica/complicações , Hospitais/estatística & dados numéricos , Cirrose Hepática/etiologia , Neoplasias Hepáticas/etiologia , Transplante de Fígado/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Progressão da Doença , Feminino , Seguimentos , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/cirurgia , Humanos , Incidência , Fígado/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Austrália Ocidental/epidemiologia
12.
Intern Med J ; 43(3): 328-33, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23441660

RESUMO

Thrombotic microangiopathy (TMA) is a potentially fatal complication in solid organ and bone marrow transplant patients, with reported incidence of 0.5-3% and mortality of about 75%. To emphasise the importance of early diagnosis and prompt commencement of therapy results in improved clinical outcomes. A retrospective study of all patients who underwent orthotopic liver transplantation (OLTX) at the Western Australian Liver Transplantation Service from May 1994 to December 2010 was conducted to identify patients who developed tacrolimus-induced TMA. We identified four patients with tacrolimus-induced TMA post-OLTX, derived from a cohort of 104 patients treated with tacrolimus in our institution. The mean age at diagnosis was 40 years, and the mean time of onset was 63 ± 7.5 weeks after OLTX. The indications for OLTX in the four patients were fulminant hepatic failure in three (Wilson disease, paracetamol overdose and post-partum thrombotic thrombocytopenic purpura) and hepatitis C virus-related cirrhosis. All patients had tacrolimus post-OLTX. At diagnosis, tacrolimus was discontinued in all patients, and three of the four patients underwent plasma exchange and all patients improved clinically. Mean duration of follow up was 15 ± 7.5 months. There was no mortality 6 months post-TMA. Early diagnosis with immediate discontinuation or conversion of calcineurin inhibitors and plasma exchange should be offered to OLTX patients with TMA as it results in good outcomes.


Assuntos
Imunossupressores/efeitos adversos , Transplante de Fígado/efeitos adversos , Tacrolimo/efeitos adversos , Microangiopatias Trombóticas/induzido quimicamente , Microangiopatias Trombóticas/diagnóstico , Adulto , Estudos de Coortes , Feminino , Seguimentos , Humanos , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Microangiopatias Trombóticas/imunologia , Adulto Jovem
13.
Cytogenet Genome Res ; 136(2): 117-22, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22286663

RESUMO

Studies in humans have suggested the possible involvement of melanocortin-3-receptor (MC3R) and other components of the central melanocortin system in host defense against mycobacteria. We report a genomic DNA nucleotide sequence highly homologous to human MC3R in several bovids and non-bovid African wildlife species. Nucleotide sequence analysis indicates that the orthologous genes of cattle and buffalo are highly homologous (89.4 and 90%, respectively) to the human MC3R gene. Sequence results also identified a typical non-functional, duplicated pseudogene, MC3RP, in 7 species from the family Bovidae. No pseudogene was found in animals outside Bovidae. The presence of the pseudogene in tuberculosis-susceptible species could have possible immunomodulatory effects on susceptibility to bovine tuberculosis infection, as well as a considerable influence on energy metabolism and food conversion efficiency.


Assuntos
Predisposição Genética para Doença/genética , Pseudogenes/genética , Receptor Tipo 3 de Melanocortina/genética , Ruminantes/genética , Tuberculose/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Búfalos/genética , Bovinos/genética , Humanos , Hyaenidae/genética , Dados de Sequência Molecular , Perissodáctilos/genética , Filogenia , Receptor Tipo 3 de Melanocortina/classificação , Ruminantes/classificação , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Tuberculose Bovina/genética
14.
Hepatol Int ; 6(2): 457-67, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21748376

RESUMO

BACKGROUND AND GOALS: Liver fibrosis influences treatment and surveillance strategies in chronic hepatitis B (CHB). This multicenter study aimed to examine the accuracy of serum fibrosis models in CHB patients including those with low alanine aminotransferase (ALT) levels and serially in those undergoing treatment. METHOD: We examined noninvasive fibrosis models [Hepascore, Fibrotest, APRI, hepatitis e antigen (HBeAg)-positive and -negative models] in 179 CHB patients who underwent liver biopsy and fibrosis assessment by METAVIR and image morphometry. Serial Hepascore measurements were assessed in 40 subjects for up to 8.7 years. RESULTS: Hepascore was more accurate than Fibrotest [area under the curve (AUC) 0.83 vs. 0.72, P = 0.05] and HBeAg-positive model (AUC 0.83 vs. 72, P = 0.03) for significant fibrosis but was not significantly different to APRI or HBeAg-negative scores. Fibrosis area assessed by morphometry was correlated with Hepascore (r = 0.603, P < 0.001), Fibrotest (r = 0.392, P = 0.03), and HBeAg-positive (r = 0.492, P = 0.001) scores only. Among 73 patients with an ALT <60 IU/L, noninvasive models were useful to predict fibrosis (PPV 80-90%) or exclude significant fibrosis (NPV 79-100%). Hepascore increased significantly among patients monitored without treatment and reduced among patients undergoing therapy (0.05/year ± 0.03 vs. -0.04/year ± 0.02, P = 0.007). CONCLUSIONS: Serum fibrosis models are predictive of fibrosis in CHB and assist in identifying subjects with low-normal ALT levels for treatment.

15.
Intern Med J ; 39(9): 613-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19769682

RESUMO

A 46-year-old man with cirrhosis secondary to hepatitis C virus infection and alcohol underwent orthotopic liver transplantation, which required urgent re-grafting because of biliary sepsis from necrosis of the left liver lobe. Recovery was complicated by renal failure and nephrogenic systemic fibrosis (probably related to intravenous gadolinium exposure). He subsequently developed a malignant fibrous histiocytoma. We present this case highlighting the occurrence of two rare conditions in the same patient following liver transplantation. We believe this is the first case of its kind to be reported.


Assuntos
Histiocitoma Fibroso Maligno/diagnóstico , Transplante de Fígado/efeitos adversos , Dermopatia Fibrosante Nefrogênica/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Evolução Fatal , Histiocitoma Fibroso Maligno/complicações , Histiocitoma Fibroso Maligno/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Dermopatia Fibrosante Nefrogênica/etiologia , Dermopatia Fibrosante Nefrogênica/terapia , Complicações Pós-Operatórias/terapia
17.
Postgrad Med J ; 82(967): 315-22, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16679470

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is common and may progress to cirrhosis and its complications. The pathogenesis of steatosis and cellular injury is thought to be related mostly to insulin resistance and oxidative stress. Therefore, management entails identification and treatment of metabolic risk factors, improving insulin sensitivity, and increasing antioxidant defences in the liver. Weight loss and exercise improve insulin sensitivity. Bariatric surgery may improve liver histology in patients with morbid obesity. Insulin sensitising drugs showed promise in pilot trials as have a number of hepatoprotective agents. Further randomised, well controlled trials are required to determine the efficacy of these drugs.


Assuntos
Fígado Gorduroso/terapia , Antioxidantes/uso terapêutico , Exercício Físico , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/etiologia , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Síndrome Metabólica/complicações , Obesidade/complicações , Redução de Peso
18.
J Bacteriol ; 187(17): 5918-26, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16109933

RESUMO

Previous studies demonstrated that an outer membrane c-type cytochrome, OmcB, was involved in Fe(III) reduction in Geobacter sulfurreducens. An OmcB-deficient mutant was greatly impaired in its ability to reduce both soluble and insoluble Fe(III). Reintroducing omcB restored the capacity for Fe(III) reduction at a level proportional to the level of OmcB production. Here, we report that the OmcB-deficient mutant gradually adapted to grow on soluble Fe(III) but not insoluble Fe(III). The adapted OmcB-deficient mutant reduced soluble Fe(III) at a rate comparable to that of the wild type, but the cell yield of the mutant was only ca. 60% of that of the wild type under steady-state culturing conditions. Analysis of proteins and transcript levels demonstrated that expression of several membrane-associated cytochromes was higher in the adapted mutant than in the wild type. Further comparison of transcript levels during steady-state growth on Fe(III) citrate with a whole-genome DNA microarray revealed a significant shift in gene expression in an apparent attempt to adapt metabolism to the impaired electron transport to Fe(III). These results demonstrate that, although there are many other membrane-bound c-type cytochromes in G. sulfurreducens, increased expression of these cytochromes cannot completely compensate for the loss of OmcB. The concept that outer membrane cytochromes are promiscuous reductases that are interchangeable in function appears to be incorrect. Furthermore, the results indicate that there may be different mechanisms for electron transfer to soluble Fe(III) and insoluble Fe(III) oxides in G. sulfurreducens, which emphasizes the importance of studying electron transport to the environmentally relevant Fe(III) oxides.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Compostos Férricos/metabolismo , Geobacter/fisiologia , Adaptação Fisiológica , Proteínas da Membrana Bacteriana Externa/genética , Sequência de Bases , Citocromos c/genética , Citocromos c/metabolismo , Primers do DNA , Transporte de Elétrons , Regulação Bacteriana da Expressão Gênica , Geobacter/genética , Geobacter/crescimento & desenvolvimento , Geobacter/metabolismo , Cinética , Oxirredução , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Diabet Med ; 22(9): 1129-33, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16108837

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is present in up to one-third of the general population and in the majority of patients with metabolic risk factors such as obesity and diabetes. Insulin resistance is a key pathogenic factor resulting in hepatic fat accumulation. Recent evidence demonstrates NAFLD in turn exacerbates hepatic insulin resistance and often precedes glucose intolerance. Once hepatic steatosis is established, other factors, including oxidative stress, mitochondrial dysfunction, gut-derived lipopolysaccharide and adipocytokines, may promote hepatocellular damage, inflammation and progressive liver disease. Confirmation of the diagnosis of NAFLD can usually be achieved by imaging studies, however, staging the disease requires a liver biopsy. NAFLD is associated with an increased risk of all-cause death, probably because of complications of insulin resistance such as vascular disease, as well as cirrhosis and hepatocellular carcinoma, which occur in a minority of patients. NAFLD is also now recognized to account for a substantial proportion of patients previously diagnosed with 'cryptogenic cirrhosis'. Diabetes, obesity and the necroinflammatory form of NAFLD known as non-alcoholic steatohepatitis, are risk factors for progressive liver disease. Current treatment relies on weight loss and exercise, although various insulin-sensitizing medications appear promising. Further research is needed to identify which patients will achieve the most benefit from therapy.


Assuntos
Fígado Gorduroso/fisiopatologia , Fígado Gorduroso/complicações , Fígado Gorduroso/terapia , Humanos , Resistência à Insulina/fisiologia , Fígado/metabolismo , Síndrome Metabólica/complicações , Estresse Oxidativo/fisiologia , Fatores de Risco
20.
Endoscopy ; 36(5): 402-4, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15100947

RESUMO

BACKGROUND AND STUDY AIMS: Nonattendance at outpatient endoscopy leads to inefficiency and delay in diagnosis. We aimed to identify factors associated with failure to attend outpatient gastroscopy and colonoscopy. PATIENTS AND METHODS: We carried out a retrospective audit of nonattendance at outpatient endoscopy over a 12-month period at our tertiary hospital endoscopy unit. Attending patients on the same endoscopy list were used as controls. Patient charts and referral letters were reviewed. The information collected included referral source, time between referral and procedure, indication and type of procedure, reason for nonattendance and history of previous endoscopy. Following the audit a trial of telephone reminders was implemented over a 3-month period. RESULTS: From 2157 outpatient procedures that were scheduled, 263 nonattendees (12.2 %) were identified with 261 controls. Of the nonattendees, 109 (41 %) did not attend for colonoscopy, 121 (46 %) did not attend for gastroscopy and 33 (13 %) failed to turn up for combined procedures. Monday was the most common day of the week for nonattendance (40 % of nonattenders). Nonattendees were younger (46 +/- 14 vs. 55 +/- 16, P < 0.001), less likely to be referred from a gastroenterologist ( P < 0.001) or private practice ( P = 0.02) and more likely to be referred from the emergency department ( P = 0.007). Subsequent to this, a 3-month period of telephone reminder reduced nonattendance rates from 12.2 % to 9 % ( P = 0.03). CONCLUSIONS: Younger patients scheduled for outpatient endoscopy on Mondays who are not referred by a gastroenterologist or private physician are more likely not to attend. These patients should be targeted for interventions designed to increase attendance. Telephone reminders have a modest effect on reducing nonattendance rates.


Assuntos
Assistência Ambulatorial , Colonoscopia , Gastroscopia , Recusa do Paciente ao Tratamento , Adulto , Fatores Etários , Idoso , Agendamento de Consultas , Feminino , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Encaminhamento e Consulta , Sistemas de Alerta , Estudos Retrospectivos , Fatores de Risco
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