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1.
Arch Toxicol ; 98(1): 251-266, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37819454

RESUMO

A suite of in vitro assays and in silico models were evaluated to identify which best detected the endocrine-disrupting (ED) potential of 10 test chemicals according to their estrogenic, androgenic and steroidogenic (EAS) potential compared to the outcomes from ToxCast. In vitro methods included receptor-binding, CALUX transactivation, H295R steroidogenesis, aromatase activity inhibition and the Yeast oestrogen (YES) and Yeast androgen screen (YAS) assays. The impact of metabolism was also evaluated. The YES/YAS assays exhibited a high sensitivity for ER effects and, despite some challenges in predicting AR effects, is a good initial screening assay. Results from receptor-binding and CALUX assays generally correlated and were in accordance with classifications based on ToxCast assays. ER agonism and AR antagonism of benzyl butyl phthalate were abolished when CALUX assays included liver S9. In silico final calls were mostly in agreement with the in vitro assays, and predicted ER and AR effects well. The efficiency of the in silico models (reflecting applicability domains or inconclusive results) was 43-100%. The percentage of correct calls for ER (50-100%), AR (57-100%) and aromatase (33-100%) effects when compared to the final ToxCast call covered a wide range from highly reliable to less reliable models. In conclusion, Danish (Q)SAR, Opera, ADMET Lab LBD and ProToxII models demonstrated the best overall performance for ER and AR effects. These can be combined with the YES/YAS assays in an initial screen of chemicals in the early tiers of an NGRA to inform on the MoA and the design of mechanistic in vitro assays used later in the assessment. Inhibition of aromatase was best predicted by the Vega, AdmetLab and ProToxII models. Other mechanisms and exposure should be considered when making a conclusion with respect to ED effects.


Assuntos
Androgênios , Disruptores Endócrinos , Androgênios/metabolismo , Androgênios/farmacologia , Estrogênios/farmacologia , Aromatase , Saccharomyces cerevisiae/metabolismo , Receptores Androgênicos/metabolismo , Estrona , Disruptores Endócrinos/química
2.
J Dairy Sci ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608948

RESUMO

Quantifying the impact of thermal stress on milk yields is essential to effectively manage present and future risks in dairy systems. Despite the existence of numerous heat indices designed to communicate stress thresholds, little information is available regarding the accuracy of different indices in estimating milk yield losses from both cold and heat stress at large spatio-temporal scales. To address this gap, we comparatively analyzed the performance of existing thermal indices in capturing US milk yield response to both cold and heat stress at the national scale. We selected four commonly used thermal indices: the Temperature and Humidity Index (THI), Black Globe Humidity Index (BGHI), Adjusted Temperature and Humidity Index (THIadj), and Comprehensive Climate Index (CCI). Using a statistical panel regression model with observational and reanalysis weather data from 1981-2020, we systematically compared the patterns of yield sensitivities and statistical performance of the four indices. We found that the US state-level milk yield variability was better explained by the THIadj and CCI, which combine the effects of temperature, humidity, wind, and solar radiation. Our analysis also reveals a continuous and nonlinear responses of milk yields to a range of cold to heat stress across all four indices. This implies that solely relying on fixed thresholds of these indices to model milk yield changes may be insufficient to capture cumulative thermal stress. Cold extremes reduced milk yields comparably to those impacted by heat extremes on the national scale. Additionally, we found large spatial variability in milk yield sensitivities, implying further limitations to the use of fixed thresholds across locations. Moreover, we found decreased yield sensitivity to thermal stress in the most recent two decades, suggesting adaptive changes in management to reduce weather-related risks.

3.
J Dairy Sci ; 106(12): 8942-8952, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37678784

RESUMO

Heat stress (HS) during the dry period can affect animal welfare, health, dry matter intake (DMI), and milk production in the subsequent lactation, which will negatively affect the profitability of dairy farms. In this study, the objective was to model the changes in DMI in pregnant nonlactating heat-stressed dairy cows with or without access to evaporative cooling systems. A database was built, composed of individual DMI records from 244 pregnant nonlactating dairy cows from an average -29.3 d (range: -42 to -21 d; SD: ±7.54 d) to -1 d relative to calving (DRC) and housed in environmental conditions in which temperature-humidity index (THI) ranged from 58.4 to 83.3, with or without access to evaporative cooling systems. Generalized additive mixed-effects models were used to describe the relationships of DMI with HS and DRC. Changes in DMI with the increase in THI and the progression of pregnancy in cows with or without evaporative cooling systems were estimated using differential equations. On average, cows housed in barns without evaporative cooling systems had a reduction in DMI of 1.30 kg/d and increased rectal temperature in 0.22°C in relation to those housed in barns with evaporative cooling systems. Dry matter intake decreased as THI increased, but the reduction was greater for noncooled cows as THI values increased. In addition, regardless of the THI, DMI started to decrease at -14 DRC for cooled cows, whereas for noncooled cows it already started at -30 DRC, relative to the previous days evaluated. The intensity of the reduction was lesser for cows that had access to evaporative cooling systems or were in the dry period in May to June as compared with those that were in the dry period in July to August or September to October. The models generated in this study, which include environmental variables, should lead to more accurate predictions of DMI during HS that can be used to formulate diets to meet the needs of the late pregnant cow because it is possible to predict changes in DMI as the heat load and DRC change. Such models are also expected to help dairy nutritionists to decide when and how to apply the dietary strategies available to attenuate the reductions in DMI with the intensity of HS and progression of pregnancy.


Assuntos
Temperatura Alta , Leite , Gravidez , Feminino , Bovinos , Animais , Lactação , Ingestão de Alimentos , Resposta ao Choque Térmico , Dieta/veterinária
4.
J Dairy Sci ; 106(7): 4725-4737, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37225587

RESUMO

Heat stress (HS) negatively affects dry matter intake (DMI), milk yield (MY), feed efficiency (FE), and free water intake (FWI) in dairy cows, with detrimental consequences to animal welfare, health, and profitability of dairy farms. Absolute enteric methane (CH4) emission, yield (CH4/DMI), and intensity (CH4/MY) may also be affected. Therefore, the goal of this study was to model the changes in dairy cow productivity, water intake, and absolute CH4 emissions, yield, and intensity with the progression (days of exposure) of a cyclical HS period in lactating dairy cows. Heat stress was induced by increasing the average temperature by 15°C (from 19°C in the thermoneutral period to 34°C) while keeping relative humidity constant at 20% (temperature-humidity index peaks of approximately 83) in climate-controlled chambers for up to 20 d. A database composed of individual records (n = 1,675) of DMI and MY from 82 heat-stressed lactating dairy cows housed in environmental chambers from 6 studies was used. Free water intake was also estimated based on DMI, dry matter, crude protein, sodium, and potassium content of the diets, and ambient temperature. Absolute CH4 emissions was estimated based on DMI, fatty acids, and dietary digestible neutral detergent fiber content of the diets. Generalized additive mixed-effects models were used to describe the relationships of DMI, MY, FE, and absolute CH4 emissions, yield, and intensity with HS. Dry matter intake and absolute CH4 emissions and yield reduced with the progression of HS up to 9 d, when it started to increase again up to 20 d. Milk yield and FE reduced with the progression of HS up to 20 d. Free water intake (kg/d) decreased during the exposure to HS mainly because of a reduction in DMI; however, when expressed in kg/kg of DMI it increased modestly. Methane intensity also reduced initially up to d 5 during HS exposure but then started to increase again following the DMI and MY pattern up to d 20. However, the reductions in CH4 emissions (absolute, yield, and intensity) occurred at the expense of decreases in DMI, MY, and FE, which are not desirable. This study provides quantitative predictions of the changes in animal performance (DMI, MY, FE, FWI) and CH4 emissions (absolute, yield, and intensity) with the progression of HS in lactating dairy cows. The models developed in this study could be used as a tool to help dairy nutritionists to decide when and how to adopt strategies to mitigate the negative effects of HS on animal health and performance and related environmental costs. Thus, more precise and accurate on-farm management decisions could be taken with the use of these models. However, application of the developed models outside of the ranges of temperature-humidity index and period of HS exposure included in this study is not recommended. Also, validation of predictive capacity of the models to predict CH4 emissions and FWI using data from in vivo studies where these variables are measured in heat-stressed lactating dairy cows is required before these models can be used.


Assuntos
Lactação , Metano , Feminino , Bovinos , Animais , Metano/metabolismo , Leite/química , Dieta/veterinária , Fibras na Dieta/metabolismo
5.
BJOG ; 128(8): 1293-1303, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33338292

RESUMO

OBJECTIVE: Caesarean section (CS) interrupts mother-to-newborn microbial transfer at birth. Beyond the neonatal period, the impact of CS on offspring gut microbiota and their short-chain fatty acids (SCFAs) remains unclear. Here, we examine birth delivery mode (CS versus vaginal delivery) with the infant gut microbiota and faecal SCFAs measured 3 and 12 months after birth. DESIGN: Longitudinal study. SETTING: North Carolina. POPULATION: In 2013-15, we enrolled pregnant women and followed up their offspring for 12 months. We asked a subset of participants, enrolled over a 3-month period, to provide faecal samples at the 3- and 12-month follow-up visits. METHODS AND MAIN OUTCOMES: We sequenced the 16S rRNA V4 region with Illumina MiSeq and quantified SCFA concentrations using gas chromatography. We examined delivery mode with differential abundance of microbiota amplicon sequence variants (ASVs) using beta-binomial regression and faecal SCFAs using linear regression. We adjusted models for confounders. RESULTS: Of the 70 infants in our sample, 25 (36%) were delivered by CS. Compared with vaginal delivery, CS was associated with differential abundance of 14 infant bacterial ASVs at 3 months and 13 ASVs at 12 months (all FDR P < 0.05). Of note, CS infants had a higher abundance of the potential pathobionts Clostridium neonatale (P = 0.04) and Clostridium perfringens (P = 0.04) and a lower abundance of potentially beneficial Bifidobacterium and Bacteroides spp. (both P < 0.05) at 3 months. Other ASVs were differentially abundant at 12 months. Infants delivered by CS also had higher faecal butyrate concentration at 3 months (P < 0.005) but not at 12 months. CONCLUSIONS: Caesarean section was associated with increased butyrate excretion, decreased Bifidobacterium and Bacteroides spp., and more colonisation of the infant gut by pathobionts at 3 months of age. CS was also associated with altered gut microbiota composition, but not faecal SCFAs, at 12 months. TWEETABLE ABSTRACT: Caesarean section delivery was associated with increased butyrate excretion, decreased Bifidobacterium, and increased colonisation of the infant gut by pathobionts at 3 months of age.


Assuntos
Cesárea , Parto Obstétrico , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Microbioma Gastrointestinal , Adulto , Bacteroides/isolamento & purificação , Bifidobacterium/isolamento & purificação , Butiratos/metabolismo , Clostridium/isolamento & purificação , Clostridium perfringens/isolamento & purificação , Fezes/química , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Gravidez , Estudos Prospectivos , Adulto Jovem
6.
Phys Rev Lett ; 122(5): 050403, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30821997

RESUMO

Aiming at a better understanding of anomalous and topological effects in gauge theories out of equilibrium, we study the real-time dynamics of a prototype model for CP violation, the massive Schwinger model with a θ term. We identify dynamical quantum phase transitions between different topological sectors that appear after sufficiently strong quenches of the θ parameter. Moreover, we establish a general dynamical topological order parameter, which can be accessed through fermion two-point correlators and, importantly, which can be applied for interacting theories. Enabled by this result, we show that the topological transitions persist beyond the weak-coupling regime. Finally, these effects can be observed with tabletop experiments based on existing cold-atom, superconducting-qubit, and trapped-ion technology. Our Letter thus presents a significant step towards quantum simulating topological and anomalous real-time phenomena relevant to nuclear and high-energy physics.

7.
Am J Transplant ; 18(7): 1745-1754, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29349869

RESUMO

Clostridium difficile infection (CDI) is a leading cause of infectious diarrhea in solid organ transplant recipients (SOT). We aimed to assess incidence, risk factors, and outcome of CDI within the Swiss Transplant Cohort Study (STCS). We performed a case-control study of SOT recipients in the STCS diagnosed with CDI between May 2008 and August 2013. We matched 2 control subjects per case by age at transplantation, sex, and transplanted organ. A multivariable analysis was performed using conditional logistic regression to identify risk factors and evaluate outcome of CDI. Two thousand one hundred fifty-eight SOT recipients, comprising 87 cases of CDI and 174 matched controls were included. The overall CDI rate per 10 000 patient days was 0.47 (95% confidence interval ([CI] 0.38-0.58), with the highest rate in lung (1.48, 95% CI 0.93-2.24). In multivariable analysis, proven infections (hazard ratio [HR] 2.82, 95% CI 1.29-6.19) and antibiotic treatments (HR 4.51, 95% CI 2.03-10.0) during the preceding 3 months were independently associated with the development of CDI. Despite mild clinical presentations, recipients acquiring CDI posttransplantation had an increased risk of graft loss (HR 2.24, 95% CI 1.15-4.37; P = .02). These findings may help to improve the management of SOT recipients.


Assuntos
Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/epidemiologia , Rejeição de Enxerto/etiologia , Transplante de Órgãos/efeitos adversos , Complicações Pós-Operatórias , Transplantados/estatística & dados numéricos , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/microbiologia , Feminino , Seguimentos , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Suíça/epidemiologia
8.
Transpl Infect Dis ; 20(4): e12898, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29668068

RESUMO

BACKGROUND: There is lack of recent multicenter epidemiological data on invasive aspergillosis (IA) among solid organ transplant recipient (SOTr) in the mold-acting antifungal era. We describe the epidemiology and outcomes of IA in a contemporary cohort of SOTr using the Swiss Transplant Cohort Study. METHODS: All consecutive SOTr with proven or probable IA between 01.05.2008 and 31.12.2014 were included. A case-control study to identify IA predictors was performed: 1-case was matched with 3-controls based on SOT type, transplant center, and time post-SOT. RESULTS: Among 2868 SOTr, 70 (2.4%) patients were diagnosed with proven (N: 30/70, 42.9%) or probable (N: 40/70, 57.1%) IA. The incidence of IA was 8.3%, 7.1%, 2.6%, 1.3%, and 1.2% in lung, heart, combined, kidney, and liver transplant recipients, respectively, Galactomannan immunoassay was positive in 1/3 of patients tested. Only 33/63 (52.4%) of patients presented with typical pulmonary radiographic findings. Predictors of IA included: renal insufficiency, re-operation, and bacterial and viral infections. 12-week mortality was higher in liver (85.7%, 6/7) compared to other (15.9%, 10/63; P < .001) SOTr. CONCLUSIONS: Invasive aspergillosis remains a rare complication post-SOT, with atypical radiographic presentations and low positivity rates of biomarkers posing significant diagnostic challenges. Although overall mortality has decreased in SOTr, it remains high in liver SOTr.


Assuntos
Aspergillus/isolamento & purificação , Terapia de Imunossupressão/efeitos adversos , Aspergilose Pulmonar Invasiva/epidemiologia , Transplante de Órgãos/efeitos adversos , Adolescente , Adulto , Idoso , Biomarcadores/análise , Estudos de Casos e Controles , Feminino , Seguimentos , Rejeição de Enxerto/prevenção & controle , Humanos , Incidência , Aspergilose Pulmonar Invasiva/diagnóstico , Aspergilose Pulmonar Invasiva/microbiologia , Pulmão/diagnóstico por imagem , Pulmão/microbiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia , Fatores de Risco , Suíça/epidemiologia , Transplantados , Adulto Jovem
9.
Am J Transplant ; 17(7): 1813-1822, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28039960

RESUMO

We assessed the impact of antiviral preventive strategies on the incidence of herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections in a nationwide cohort of transplant recipients. Risk factors for the development of HSV or VZV infection were assessed by Cox proportional hazards regression. We included 2781 patients (56% kidney, 20% liver, 10% lung, 7.3% heart, 6.7% others). Overall, 1264 (45%) patients received antiviral prophylaxis (ganciclovir or valganciclovir, n = 1145; acyclovir or valacyclovir, n = 138). Incidence of HSV and VZV infections was 28.9 and 12.1 cases, respectively, per 1000 person-years. Incidence of HSV and VZV infections at 1 year after transplant was 4.6% (95% confidence interval [CI] 3.5-5.8) in patients receiving antiviral prophylaxis versus 12.3% (95% CI 10.7-14) in patients without prophylaxis; this was observed particularly for HSV infections (3% [95% CI 2.2-4] versus 9.8% [95% CI 8.4-11.4], respectively). A lower rate of HSV and VZV infections was also seen in donor or recipient cytomegalovirus-positive patients receiving ganciclovir or valganciclovir prophylaxis compared with a preemptive approach. Female sex (hazard ratio [HR] 1.663, p = 0.001), HSV seropositivity (HR 5.198, p < 0.001), previous episodes of rejection (HR 1.95, p = 0.004), and use of a preemptive approach (HR 2.841, p = 0.017) were significantly associated with a higher risk of HSV infection. Although HSV and VZV infections were common after transplantation, antiviral prophylaxis significantly reduced symptomatic HSV infections.


Assuntos
Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Rejeição de Enxerto/prevenção & controle , Infecções por Herpesviridae/prevenção & controle , Transplante de Órgãos/efeitos adversos , Adulto , Estudos de Coortes , Citomegalovirus/efeitos dos fármacos , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/virologia , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/virologia , Sobrevivência de Enxerto , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/virologia , Herpesvirus Humano 3/efeitos dos fármacos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Suíça/epidemiologia , Transplantados
10.
Am J Transplant ; 17(10): 2591-2600, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28326672

RESUMO

BK polyomavirus (BKPyV) causes premature kidney transplant (KT) failure in 1-15% of patients. Because antivirals are lacking, most programs screen for BKPyV-viremia and, if positive, reduce immunosuppression. To evaluate the relationship of viremia and BKPyV-specific immunity, we examined prospectively cryopreserved plasma and peripheral blood mononuclear cells at the time of transplantation (T0) and at 6 mo (T6) and 12 mo (T12) after transplant from 28 viremic KT patients and 68 nonviremic controls matched for the transplantation period. BKPyV IgG seroprevalence was comparable between cases (89.3%) and controls (91.2%; p = 0.8635), but cases had lower antibody levels (p = 0.022) at T0. Antibody levels increased at T6 and T12 but were not correlated with viremia clearance. BKPyV-specific T cell responses to pools of overlapping 15mers (15mer peptide pool [15mP]) or immunodominant CD8 9mers (9mer peptide pool [9mP]) from the early viral gene region were not different between cases and controls at T0; however, clearance of viremia was associated with stronger 9mP responses at T6 (p = 0.042) and T12 (p = 0.048), whereas 15mP responses were not informative (T6 p = 0.359; T12 p = 0.856). BKPyV-specific T cells could be expanded in vitro from all patients after transplant, permitting identification of 78 immunodominant 9mer epitopes including 50 new ones across different HLA class I. Thus, 9mP-responses may be a novel marker of reconstituting CD8 T cell function that warrants further study as a complement of plasma BKPyV loads for guiding immunosuppression reduction.


Assuntos
Vírus BK/fisiologia , Linfócitos T CD8-Positivos/imunologia , Transplante de Rim , Adulto , Idoso , Vírus BK/isolamento & purificação , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Viremia
11.
Int J Obes (Lond) ; 41(4): 497-501, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27899809

RESUMO

BACKGROUND/OBJECTIVES: The intergenerational association of obesity may be driven by mother-to-newborn transmission of microbiota at birth. Yet cesarean delivery circumvents newborn acquisition of vaginal microbiota, and has been associated with greater childhood adiposity. Here we examined the independent and joint associations of maternal pre-pregnancy body mass index (BMI; kg m-2) and delivery mode with childhood overweight or obesity. SUBJECTS/METHODS: We prospectively followed 1441 racially and ethnically diverse mother-child dyads in the Boston Birth Cohort until age 5 years (range: 2.0-8.0 years). We used logistic regression to examine the independent and joint associations of delivery mode (cesarean and vaginal delivery) and pre-pregnancy BMI with childhood overweight or obesity (age-sex-specific BMI ⩾85th percentile). RESULTS: Of 1441 mothers, 961 delivered vaginally and 480 by cesarean. Compared with vaginally delivered children, cesarean delivered children had 1.4 (95% confidence interval (CI) 1.1-1.8) times greater odds of becoming overweight or obese in childhood, after adjustment for maternal age at delivery, race/ethnicity, education, air pollution exposure, pre-pregnancy BMI, pregnancy weight gain and birth weight. Compared with children born vaginally to normal weight mothers, after multivariable adjustment, odds of childhood overweight or obesity were highest in children born by cesarean delivery to obese mothers (odds ratio (OR): 2.8; 95% CI: 1.9-4.1), followed by children born by cesarean delivery to overweight mothers (OR: 2.2; 95% CI: 1.5-3.2), then children born vaginally to obese mothers (OR: 1.8; 95% CI: 1.3-2.6) and finally children born vaginally to overweight mothers (OR: 1.7; 95% CI: 1.2-2.3). CONCLUSIONS: In our racially and ethnically diverse cohort, cesarean delivery and pre-pregnancy overweight and obesity were associated with childhood overweight or obesity. Needed now are prospective studies that integrate measures of the maternal and infant microbiome, and other potentially explanatory covariates, to elucidate the mechanisms driving this association and to explore whether exposure to vaginal microbiota in cesarean delivered newborns may be an innovative strategy to combat the intergenerational cycle of obesity.


Assuntos
Cesárea/estatística & dados numéricos , Parto Obstétrico/estatística & dados numéricos , Microbiota/imunologia , Mães , Obesidade Infantil/imunologia , Vagina/microbiologia , Adulto , Idade de Início , Peso ao Nascer , Índice de Massa Corporal , Boston/epidemiologia , Cesárea/efeitos adversos , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Obesidade Infantil/epidemiologia , Obesidade Infantil/etiologia , Gravidez , Estudos Prospectivos , Fatores de Risco
12.
Pharmacogenomics J ; 17(1): 69-75, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26644205

RESUMO

Metabolic syndrome after transplantation is a major concern following solid organ transplantation (SOT). The CREB-regulated transcription co-activator 2 (CRTC2) regulates glucose metabolism. The effect of CRTC2 polymorphisms on new-onset diabetes after transplantation (NODAT) was investigated in a discovery sample of SOT recipients (n1=197). Positive results were tested for replication in two samples from the Swiss Transplant Cohort Study (STCS, n2=1294 and n3=759). Obesity and other metabolic traits were also tested. Associations with metabolic traits in population-based samples (n4=46'186, n5=123'865, n6>100,000) were finally analyzed. In the discovery sample, CRTC2 rs8450-AA genotype was associated with NODAT, fasting blood glucose and body mass index (Pcorrected<0.05). CRTC2 rs8450-AA genotype was associated with NODAT in the second STCS replication sample (odd ratio (OR)=2.01, P=0.04). In the combined STCS replication samples, the effect of rs8450-AA genotype on NODAT was observed in patients having received SOT from a deceased donor and treated with tacrolimus (n=395, OR=2.08, P=0.02) and in non-kidney transplant recipients (OR=2.09, P=0.02). Moreover, rs8450-AA genotype was associated with overweight or obesity (n=1215, OR=1.56, P=0.02), new-onset hyperlipidemia (n=1007, OR=1.76, P=0.007), and lower high-density lipoprotein-cholesterol (n=1214, ß=-0.08, P=0.001). In the population-based samples, a proxy of rs8450G>A was significantly associated with several metabolic abnormalities. CRTC2 rs8450G>A appears to have an important role in the high prevalence of metabolic traits observed in patients with SOT. A weak association with metabolic traits was also observed in the population-based samples.


Assuntos
Síndrome Metabólica/epidemiologia , Síndrome Metabólica/genética , Transplante de Órgãos/efeitos adversos , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Dislipidemias/epidemiologia , Dislipidemias/genética , Frequência do Gene , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Incidência , Modelos Lineares , Modelos Logísticos , Síndrome Metabólica/diagnóstico , Análise Multivariada , Obesidade/epidemiologia , Obesidade/genética , Razão de Chances , Fenótipo , Prevalência , Medição de Risco , Fatores de Risco , Suíça/epidemiologia , Fatores de Tempo , Resultado do Tratamento
13.
Allergy ; 72(12): 1962-1971, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28513859

RESUMO

BACKGROUND: Asthma is a heterogeneous chronic disease with different phenotypes and treatment responses. Thus, there is a high clinical need for molecular disease biomarkers to aid in differentiating these distinct phenotypes. As MicroRNAs (miRNAs), that regulate gene expression at the post-transcriptional level, are altered in experimental and human asthma, circulating miRNAs are attractive candidates for the identification of novel biomarkers. This study aimed to identify plasmatic miRNA-based biomarkers of asthma, through a translational approach. METHODS: We prescreened miRNAs in plasma samples from two different murine models of experimental asthma (ovalbumin and house dust mite); miRNAs deregulated in both models were further tested in a human training cohort of 20 asthma patients and 9 healthy controls. Candidate miRNAs were then validated in a second, independent group of 26 asthma patients and 12 healthy controls. RESULTS: Ten miRNA ratios consisting of 13 miRNAs were differentially regulated in both murine models. Measuring these miRNAs in the training cohort identified a biomarker signature consisting of five miRNA ratios (7 miRNAs). This signature showed a good sensitivity and specificity in the test cohort with an area under the receiver operating characteristic curve (AUC) of 0.92. Correlation of miRNA ratios with clinical characteristics further revealed associations with FVC % predicted, and oral corticosteroid or antileukotriene use. CONCLUSION: Distinct plasma miRNAs are differentially regulated both in murine and in human allergic asthma and were associated with clinical characteristics of patients. Thus, we suggest that miRNA levels in plasma might have future potential to subphenotype patients with asthma.


Assuntos
Asma/diagnóstico , Asma/genética , Biomarcadores , MicroRNA Circulante , Transcriptoma , Adulto , Idoso , Animais , Asma/sangue , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Pesquisa Translacional Biomédica , Adulto Jovem
14.
Int J Obes (Lond) ; 40(8): 1286-91, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27121250

RESUMO

BACKGROUND/OBJECTIVES: To investigate sex-specific associations of birth weight with body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) in mid-to-late adulthood. SUBJECTS/METHODS: ELSA-Brasil is a multicenter cohort study of adults aged 35-74 years affiliated with universities or research institutions of six capital cities in Brazil. After exclusions, we investigated 11 636 participants. Socio-demographic factors and birth weight were obtained by interview. All anthropometry was directly measured at baseline. We categorized birth weight as low (⩽2.5 kg); normal (2.5-4 kg) and high (⩾4 kg). We performed analysis of covariance (ANCOVA) for continuous outcomes and ordinal logistic regression for categorical adiposity outcomes. We examined interaction on the multiplicative scale by sex and by race. RESULTS: High birth weight uniformly predicted greater overall and central obesity in men and women. However, low (vs normal) birth weight, in ANCOVA models adjusted for participant age, family income, race, education, maternal education, and maternal and paternal history of diabetes, was associated with lower BMI, WC and WHR means for men, but not for women (Pinteraction=0.01, <0.0001 and <0.0001, respectively). In similarly adjusted ordinal logistic regression models, odds of obesity (odds ratio (OR)=0.65, 0.46-0.90) and of being in the high (vs low) tertile of WC (OR=0.66, 0.50-0.87) and of WHR (OR=0.79, 0.60-1.03) were lower for low (vs normal) birth weight men, but trended higher (BMI: OR=1.18, 0.92-1.51; WC: OR=1.21, 0.97-1.53; WHR: OR=1.44, 1.15-1.82) for low (vs normal) birth weight women. CONCLUSIONS: In this Brazilian sample of middle-aged and elderly adults who have lived through a rapid nutritional transition, low birth weight was associated with adult adiposity in a sex-specific manner. In men, low birth weight was associated with lower overall and central adult adiposity, while in women low birth weight was generally associated with greater central adiposity.


Assuntos
Adiposidade/fisiologia , Peso ao Nascer/fisiologia , Obesidade Abdominal/epidemiologia , Caracteres Sexuais , Adulto , Idoso , Índice de Massa Corporal , Brasil/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Nutrição , Obesidade Abdominal/complicações , Prevalência , Fatores de Risco , Fatores Sexuais , Circunferência da Cintura/fisiologia , Relação Cintura-Quadril/estatística & dados numéricos
15.
Phys Rev Lett ; 117(6): 061601, 2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27541456

RESUMO

We investigate the impact of the Adler-Bell-Jackiw anomaly on the nonequilibrium evolution of strong-field quantum electrodynamics (QED) using real-time lattice gauge theory techniques. For field strengths exceeding the Schwinger limit for pair production, we encounter a highly absorptive medium with anomaly induced dynamical refractive properties. In contrast to earlier expectations based on equilibrium properties, where net anomalous effects vanish because of the trivial vacuum structure, we find that out-of-equilibrium conditions can have dramatic consequences for the presence of quantum currents with distinctive macroscopic signatures. We observe an intriguing tracking behavior, where the system spends longest times near collinear field configurations with maximum anomalous current. Apart from the potential relevance of our findings for future laser experiments, similar phenomena related to the chiral magnetic effect are expected to play an important role for strong QED fields during initial stages of heavy-ion collision experiments.

16.
Am J Transplant ; 15(12): 3024-40, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26474168

RESUMO

Infectious diseases after solid organ transplantation (SOT) are a significant cause of morbidity and reduced allograft and patient survival; however, the influence of infection on the development of chronic allograft dysfunction has not been completely delineated. Some viral infections appear to affect allograft function by both inducing direct tissue damage and immunologically related injury, including acute rejection. In particular, this has been observed for cytomegalovirus (CMV) infection in all SOT recipients and for BK virus infection in kidney transplant recipients, for community-acquired respiratory viruses in lung transplant recipients, and for hepatitis C virus in liver transplant recipients. The impact of bacterial and fungal infections is less clear, but bacterial urinary tract infections and respiratory tract colonization by Pseudomonas aeruginosa and Aspergillus spp appear to be correlated with higher rates of chronic allograft dysfunction in kidney and lung transplant recipients, respectively. Evidence supports the beneficial effects of the use of antiviral prophylaxis for CMV in improving allograft function and survival in SOT recipients. Nevertheless, there is still a need for prospective interventional trials assessing the potential effects of preventive and therapeutic strategies against bacterial and fungal infection for reducing or delaying the development of chronic allograft dysfunction.


Assuntos
Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Infecções/complicações , Transplante de Órgãos/efeitos adversos , Aloenxertos , Anti-Infecciosos/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Humanos , Infecções/fisiopatologia , Prognóstico
17.
Am J Transplant ; 15(9): 2511-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25832127

RESUMO

A 70-year-old lung transplant recipient patient was admitted with fever, nausea, abdominal pain, peripheral edema and pronounced weakness. An initial work-up for presumed infection revealed cholestatic hepatitis, leukocytosis and thrombocytopenia, but failed to detect a pathogen. An increased glucose uptake exclusively in the liver was demonstrated by positron emission tomography. Liver biopsy showed basophilic inclusions in the cytoplasm of hepatocytes. Broad- range 16S rRNA gene PCR followed by sequence analysis yielded Spiroplasma sp. in two independent blood samples and the liver biopsy, confirming Spiroplasma sp. as the causative agent. Antibiotic treatment with doxycycline and azithromycin led to complete recovery.


Assuntos
Infecções por Bactérias Gram-Negativas/microbiologia , Hepatite/microbiologia , Hospedeiro Imunocomprometido , Transplante de Pulmão , Spiroplasma/isolamento & purificação , Idoso , Antibacterianos/uso terapêutico , DNA Bacteriano/genética , Feminino , Infecções por Bactérias Gram-Negativas/diagnóstico por imagem , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Hepatite/diagnóstico por imagem , Hepatite/tratamento farmacológico , Humanos , Doenças Pulmonares Intersticiais/cirurgia , Reação em Cadeia da Polimerase , Prognóstico , RNA Ribossômico 16S/genética , Cintilografia
18.
Int J Obes (Lond) ; 39(4): 665-70, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25298276

RESUMO

BACKGROUND/OBJECTIVES: Cesarean section (CS) and antibiotic use during pregnancy may alter normal maternal-offspring microbiota exchange, thereby contributing to aberrant microbial colonization of the infant gut and increased susceptibility to obesity later in life. We hypothesized that (i) maternal use of antibiotics in the second or third trimester of pregnancy and (ii) CS are independently associated with higher risk of childhood obesity in the offspring. SUBJECTS/METHODS: Of the 727 mothers enrolled in the Northern Manhattan Mothers and Children Study, we analyzed the 436 mother-child dyads followed until 7 years of age with complete data. We ascertained prenatal antibiotic use by a questionnaire administered late in the third trimester, and delivery mode by medical record. We derived age- and sex-specific body mass index (BMI) z-scores using the CDC SAS Macro, and defined obesity as BMI z⩾95th percentile. We used binary regression with robust variance and linear regression models adjusted for maternal age, ethnicity, pre-gravid BMI, maternal receipt of public assistance, birth weight, sex, breastfeeding in the first year and gestational antibiotics or delivery mode. RESULTS: Compared with children not exposed to antibiotics during the second or third trimester, those exposed had 84% (33-154%) higher risk of obesity, after multivariable adjustment. Second or third trimester antibiotic exposure was also positively associated with BMI z-scores, waist circumference and % body fat (all P<0.05). Independent of prenatal antibiotic usage, CS was associated with 46% (8-98%) higher offspring risk of childhood obesity. Associations were similar for elective and non-elective CS. CONCLUSIONS: In our cohort, CS and exposure to antibiotics in the second or third trimester were associated with higher offspring risk of childhood obesity. Future studies that address the limitations of our study are warranted to determine if prenatal antibiotic use is associated with offspring obesity. Research is also needed to determine if alterations in neonatal gut microbiota underlie the observed associations.


Assuntos
Antibacterianos/efeitos adversos , Cesárea/efeitos adversos , Mães , Obesidade Infantil/etiologia , Obesidade Infantil/prevenção & controle , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Antibacterianos/administração & dosagem , Peso ao Nascer , Cesárea/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Fatores de Risco , Inquéritos e Questionários
19.
Transpl Infect Dis ; 17(3): 342-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25816700

RESUMO

BACKGROUND: We previously documented that a stringent implementation of a preemptive cytomegalovirus (CMV) prevention protocol reduced the number of CMV disease episodes after kidney transplantation, when compared with a routine preemptive protocol. The impact on overall costs was assessed. METHODS: Cost comparisons were made for inpatient and outpatient costs and overall costs, using costs provided by the financial department. Variables were analyzed using the Wilcoxon rank-sum test. A multivariable global linear model evaluated the effect of all co-variables on cost differences. In Cohort 1 (n = 84), 74% were followed with a standard CMV preemptive protocol, and 26% received prophylaxis. In Cohort 2 (n = 74), an intensified CMV surveillance protocol was applied in 74% of patients, and 26% were given prophylaxis. RESULTS: Overall, Cohort 1 had significantly higher treatment costs as compared with Cohort 2 (mean Swiss francs [CHF] 104,548 and CHF 76,983, respectively, P = 0.0005). Excluding patients who received prophylaxis reduced these costs to CHF 89,318 in Cohort 1 and CHF 73,652 in Cohort 2. Outcome between Cohort 1 and 2 was comparable. CONCLUSION: A stringent adherence to the CMV prevention protocol was associated with a significant reduction in overall costs. Whether this benefit is because of the demonstrated reduction in the rate of CMV disease needs to be assessed in a randomized trial.


Assuntos
Antivirais/administração & dosagem , Infecções por Citomegalovirus/economia , Citomegalovirus/efeitos dos fármacos , Transplante de Rim/efeitos adversos , Idoso , Antivirais/economia , Estudos de Coortes , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/virologia , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Pessoa de Meia-Idade
20.
Genes Immun ; 15(7): 495-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25008861

RESUMO

Previous studies have associated activating Killer cell Immunoglobulin-like Receptor (KIR) genes with protection from cytomegalovirus (CMV) replication after organ transplantation. Whether KIR-associated protection is operating in the context of primary infection, re-activation, or both, remains unknown. Here we correlated KIR genotype and CMV serostatus at the time of transplantation with rates of CMV viremia in 517 heart (n=57), kidney (n=223), liver (n=165) or lung (n=72) allograft recipients reported to the Swiss Transplant Cohort Study. Across the entire cohort we found B haplotypes-which in contrast to A haplotypes may contain multiple activating KIR genes-to be protective in the most immunosuppressed patients (receiving anti-thymocyte globulin induction and intensive maintenance immunosuppression) (hazard ratio after adjustment for covariates 0.46, 95% confidence interval 0.29-0.75, P=0.002). Notably, a significant protection was detected only in recipients who were CMV-seropositive at the time of transplantation (HR 0.45, 95% CI 0.26-0.77, P=0.004), but not in CMV seronegative recipients (HR 0.59, 95% CI 0.22-1.53, P=0.28). These data indicate a prominent role for KIR-and presumably natural killer (NK) cells-in the control of CMV replication in CMV seropositive organ transplant recipients treated with intense immunosuppression.


Assuntos
Infecções por Citomegalovirus/genética , Transplante de Órgãos , Receptores KIR/genética , Adolescente , Adulto , Idoso , Criança , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/imunologia , Feminino , Haplótipos , Humanos , Imunidade Inata , Hospedeiro Imunocomprometido , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Viremia/etiologia , Viremia/genética , Viremia/imunologia , Replicação Viral
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