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1.
Proc Natl Acad Sci U S A ; 120(42): e2306317120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37812699

RESUMO

Space weather, including solar storms, can impact Earth by disturbing the geomagnetic field. Despite the known dependence of birds and other animals on geomagnetic cues for successful seasonal migrations, the potential effects of space weather on organisms that use Earth's magnetic field for navigation have received little study. We tested whether space weather geomagnetic disturbances are associated with disruptions to bird migration at a macroecological scale. We leveraged long-term radar data to characterize the nightly migration dynamics of the nocturnally migrating North American avifauna over 22 y. We then used concurrent magnetometer data to develop a local magnetic disturbance index associated with each radar station (ΔBmax), facilitating spatiotemporally explicit analyses of the relationship between migration and geomagnetic disturbance. After controlling for effects of atmospheric weather and spatiotemporal patterns, we found a 9 to 17% decrease in migration intensity in both spring and fall during severe space weather events. During fall migration, we also found evidence for decreases in effort flying against the wind, which may represent a depression of active navigation such that birds drift more with the wind during geomagnetic disturbances. Effort flying against the wind in the fall was most reduced under both overcast conditions and high geomagnetic disturbance, suggesting that a combination of obscured celestial cues and magnetic disturbance may disrupt navigation. Collectively, our results provide evidence for community-wide avifaunal responses to geomagnetic disturbances driven by space weather during nocturnal migration.


Assuntos
Migração Animal , Tempo (Meteorologia) , Animais , Migração Animal/fisiologia , Aves/fisiologia , Estações do Ano , Vento
2.
Am J Epidemiol ; 192(7): 1093-1104, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-36928293

RESUMO

Variability in sleep duration and cardiovascular health have been infrequently investigated, particularly among reproductive-age women. We examined these associations across the menstrual cycle among a cohort of 250 healthy premenopausal women, aged 18-44 years. The BioCycle study (New York, 2005-2007) collected cardiovascular biomarkers (serum high- and low-density lipoprotein (HDL, LDL), total cholesterol, triglycerides, and C-reactive protein (CRP)) at key time points along the menstrual cycle (follicular, ovulatory, and luteal phases). Women also recorded sleep duration in daily diaries. From these data, we computed L-moments, robust versions of location, dispersion, skewness, and kurtosis. We fitted linear mixed models with random intercepts and inverse probability weighting to estimate associations between sleep variability and cardiovascular biomarkers, accounting for demographic, lifestyle, health, and reproductive factors. Sleep dispersion (any deviation from mean duration) was associated with lower mean LDL for nonshift workers and non-White women. Skewed sleep duration was associated with higher mean CRP and lower mean total cholesterol. Sleep durations with extreme short and long bouts (kurtosis) were associated with a lower mean HDL, but not mean CRP, LDL, or triglycerides. Sleep duration modified associations between sleep dispersion and LDL, HDL, and total cholesterol. Even in young and healthy women, sleep duration variability could influence cardiovascular health.


Assuntos
Biomarcadores , Doenças Cardiovasculares , Ciclo Menstrual , Duração do Sono , Feminino , Humanos , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/epidemiologia , Colesterol , HDL-Colesterol/sangue , Triglicerídeos
3.
Biometrics ; 79(3): 2394-2403, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36511353

RESUMO

In data analysis using dimension reduction methods, the main goal is to summarize how the response is related to the covariates through a few linear combinations. One key issue is to determine the number of independent, relevant covariate combinations, which is the dimension of the sufficient dimension reduction (SDR) subspace. In this work, we propose an easily-applied approach to conduct inference for the dimension of the SDR subspace, based on augmentation of the covariate set with simulated pseudo-covariates. Applying the partitioning principal to the possible dimensions, we use rigorous sequential testing to select the dimensionality, by comparing the strength of the signal arising from the actual covariates to that appearing to arise from the pseudo-covariates. We show that under a "uniform direction" condition, our approach can be used in conjunction with several popular SDR methods, including sliced inverse regression. In these settings, the test statistic asymptotically follows a beta distribution and therefore is easily calibrated. Moreover, the family-wise type I error rate of our sequential testing is rigorously controlled. Simulation studies and an analysis of newborn anthropometric data demonstrate the robustness of the proposed approach, and indicate that the power is comparable to or greater than the alternatives.


Assuntos
Simulação por Computador , Estatística como Assunto
4.
Liver Int ; 42(7): 1557-1561, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35451173

RESUMO

Alcohol-related liver disease (ALD) is the leading indication for liver transplantation in the United States, but disparities for women with ALD exist. We sought to characterize trends in ALD hospitalizations and mortality among women. Using the National Inpatient Sample, we evaluated ALD and non-ALD discharges from 2003 to 2017. Multivariable logistic regression was used to evaluate mortality. ALD increased more rapidly among women, with alcohol hepatitis (AH) rising the most. When stratified by age and sex, changes in alcohol-related cirrhosis (AC) and AH were greater in women in nearly all age groups. Similar increases were present when stratified by race, notably for Native American and Asian women. AH mortality increased in women in almost all age groups. While ALD remains predominantly male, discharges and mortality have disproportionately increased among women, particularly in young women and Native Americans. These findings shed light on populations in need of intensive public health interventions.


Assuntos
Hepatite Alcoólica , Hepatopatias Alcoólicas , Transplante de Fígado , Feminino , Hepatite Alcoólica/epidemiologia , Hospitalização , Humanos , Pacientes Internados , Cirrose Hepática Alcoólica , Hepatopatias Alcoólicas/epidemiologia , Masculino , Estados Unidos/epidemiologia
5.
J Clin Periodontol ; 49(7): 672-683, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35561034

RESUMO

AIM: To assess the prognostic value of soft tissue phenotype modification following root coverage procedures for predicting the long-term (10-year) behaviour of the gingival margin. MATERIALS AND METHODS: Participants from six randomized clinical trials on root coverage procedures at the University of Michigan were re-invited for a longitudinal evaluation. Clinical measurements were obtained by two calibrated examiners. A data-driven approach to model selection with Akaike information criterion (AIC) was carried out via multilevel regression analyses and partial regression plotting for changes in the level of the gingival margin over time and interactions with the early (6-month) results of soft tissue phenotypic modification. RESULTS: One-hundred and fifty-seven treated sites in 83 patients were re-assessed at the long-term recall. AIC-driven model selection and regression analyses demonstrated that 6-month keratinized tissue width (KTW) and gingival thickness (GT) influenced the trajectory of the gingival margin similarly in a concave manner; however, GT was the driving determinant that predicted significantly less relapse in the treatments, with stability of the treated gingival margin obtained beyond values of 1.46 mm. CONCLUSIONS: Among a compliant patient cohort, irrespective of the rendered therapy, the presence of at least 1.5 mm KTW and 1.46 mm GT was correlated with the long-term stability of the gingival margin.


Assuntos
Retração Gengival , Tecido Conjuntivo , Gengiva , Retração Gengival/cirurgia , Humanos , Fenótipo , Ensaios Clínicos Controlados Aleatórios como Assunto , Raiz Dentária , Resultado do Tratamento
6.
Mol Biol Evol ; 37(2): 429-441, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639821

RESUMO

Genomic imprinting leads to mono-allelic expression of genes based on parent of origin. Therian mammals and angiosperms evolved this mechanism in nutritive tissues, the placenta, and endosperm, where maternal and paternal genomes are in conflict with respect to resource allocation. We used RNA-seq to analyze allelic bias in the expression of 91 known imprinted genes in term human placentas from a prospective cohort study in Mali. A large fraction of the imprinted exons (39%) deviated from mono-allelic expression. Loss of imprinting (LOI) occurred in genes with either maternal or paternal expression bias, albeit more frequently in the former. We characterized LOI using binomial generalized linear mixed models. Variation in LOI was predominantly at the gene as opposed to the exon level, consistent with a single promoter driving the expression of most exons in a gene. Some genes were less prone to LOI than others, particularly lncRNA genes were rarely expressed from the repressed allele. Further, some individuals had more LOI than others and, within a person, the expression bias of maternally and paternally imprinted genes was correlated. We hypothesize that trans-acting maternal effect genes mediate correlated LOI and provide the mother with an additional lever to control fetal growth by extending her influence to LOI of the paternally imprinted genes. Limited evidence exists to support associations between LOI and offspring phenotypes. We show that birth length and placental weight were associated with allelic bias, making this the first comprehensive report of an association between LOI and a birth phenotype.


Assuntos
Peso ao Nascer/genética , Estatura/genética , Perfilação da Expressão Gênica/métodos , Impressão Genômica , Placenta/química , Adolescente , Feminino , Humanos , Recém-Nascido , Modelos Lineares , Mali , Herança Materna , Gravidez , Regiões Promotoras Genéticas , Estudos Prospectivos , Análise de Sequência de RNA , Adulto Jovem
7.
Liver Int ; 41(5): 1012-1019, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33529460

RESUMO

BACKGROUND & AIMS: Bariatric surgery is common, but alcohol misuse has been reported following these procedures. We aimed to determine if bariatric surgery is associated with increased risk of alcohol-related cirrhosis (AC) and alcohol misuse. METHODS: Retrospective observational analysis of obese adults with employer-sponsored insurance administrative claims from 2008 to 2016. Subjects with diagnosis codes for bariatric surgery were included. Primary outcome was risk of AC. Secondary outcome was risk of alcohol misuse. Bariatric surgery was divided into before 2008 and after 2008 to account for patients who had a procedure during the study period. Cox proportional hazard regression models using age as the time variable were used with interaction analyses for bariatric surgery and gender. RESULTS: A total of 194 130 had surgery from 2008 to 2016 while 209 090 patients had bariatric surgery prior to 2008. Age was 44.1 years, 61% women and enrolment was 3.7 years. A total of 4774 (0.07%) had AC. Overall risk of AC was lower for those who received sleeve gastrectomy and laparoscopic banding during the study period (HR 0.4, P <.001; HR 0.43, P =.02) and alcohol misuse increased for Roux-en-Y and sleeve gastrectomy recipients (HR 1.86 and 1.35, P <.001, respectively). In those who had surgery before 2008, women had increased risk of AC and alcohol misuse compared to women without bariatric surgery (HR 2.1 [95% CI: 1.79-2.41] for AC; HR 1.98 [95% CI 1.93-2.04]). CONCLUSIONS: Bariatric surgery is associated with a short-term decreased risk of AC but potential long-term increased risk of AC in women. Post-operative alcohol surveillance is necessary to reduce this risk.


Assuntos
Alcoolismo , Cirurgia Bariátrica , Derivação Gástrica , Laparoscopia , Obesidade Mórbida , Adulto , Alcoolismo/complicações , Alcoolismo/epidemiologia , Cirurgia Bariátrica/efeitos adversos , Feminino , Humanos , Cirrose Hepática Alcoólica , Masculino , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
8.
Nephrol Dial Transplant ; 36(10): 1882-1892, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-33068410

RESUMO

BACKGROUND: Lower urinary excretion of the kidney tubule-specific biomarker epidermal growth factor (uEGF) is associated with increased risk of renal function [glomerular filtration rate (GFR)] loss in diabetes and in patients with established chronic kidney disease (CKD). We investigated whether uEGF is associated with rapid GFR decline or incident CKD in the general population. METHODS: Subjects without CKD or diabetes were recruited from the general population in Tromso, Norway [Renal Iohexol Clearance Survey (RENIS); N = 1249] and Groningen, the Netherlands [Prevention of REnal and Vascular END-stage disease (PREVEND); N = 4534], with a median follow-up of 5.6 and 7.4 years, respectively. GFR was measured by iohexol clearance in the RENIS and estimated using the CKD Epidemiology Collaboration creatinine-cystatin C equation in the PREVEND study. Rapid GFR decline was defined as an annual GFR loss >3.0 mL/min/1.73 m2 and in sensitivity analyses as subjects with the 10% steepest GFR slope within each cohort. RESULTS: Lower baseline uEGF excretion was associated with rapid GFR loss in both cohorts {RENIS, odds ratio [OR] per 1 µg/mmol lower uEGF 1.42 [95% confidence interval (CI) 1.06-1.91], P = 0.02; PREVEND, OR 1.29 [95% CI 1.10-1.53], P < 0.01}, adjusted for baseline GFR, albumin:creatinine ratio and conventional CKD risk factors. Similar results were obtained using the outcome of the 10% steepest GFR slope in each cohort. Lower uEGF levels were associated with incident CKD in the combined analysis of both cohorts. CONCLUSIONS: Lower uEGF levels are associated with increased risk of rapid GFR loss and incident CKD in the general population. This finding, together with previous findings in CKD and high-risk populations, supports that uEGF may serve as a broadly applicable biomarker representing the tubular component of the current glomerulus-centric clinical risk assessment system.


Assuntos
Fator de Crescimento Epidérmico , Rim/fisiopatologia , Insuficiência Renal Crônica , Creatinina , Progressão da Doença , Fator de Crescimento Epidérmico/urina , Taxa de Filtração Glomerular , Humanos , Países Baixos , Noruega , Insuficiência Renal Crônica/diagnóstico
9.
Br J Nutr ; : 1-10, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34511160

RESUMO

Sleep hygiene recommendations discourage eating before bedtime; however, the impact of mealtime on sleep has been inconsistent. We examined gender-stratified associations between eating or drinking <1, <2 and <3 h before bedtime, sleep duration and wake after sleep onset (WASO >30 min). This study utilised 2003-2018 data from the American Time Use Survey, a nationally representative sample of USA residents aged ≥15 years. Participants recorded weekday/weekend activities during a 24-h period. Age-specific sleep duration and WASO were estimated categorically and continuously. Eating or drinking were identified from all activities recorded <1, <2 and <3 h before bedtime. Mean ± se sleep duration was 8·0 ± 0·006 h, and 6% of participants ate or drank <1 h prior to weekdays bedtime. Overall, eating or drinking <1 h prior to bedtime was associated with longer weekdays sleep duration. Women and men who ate or drank <1 h before bedtime, v. those who did not, had 35 min (95% CI (30,39)) and 25 min (95 % CI (21,29)) longer sleep duration, respectively, as well as increased odds of WASO; women (OR=2·03, 95% CI (1·66,2·49)) and men (OR=2·64, 95% CI (2·08,3·36)). As the interval of eating or drinking prior to bedtime expanded, odds of short and long sleep durations and WASO decreased. This population-based data linked eating or drinking <1 h before bedtime to longer sleep duration, but increased WASO. Eating or drinking further from bedtime lowers the odds of short and long sleep duration and WASO. Causal pathways are difficult to discern, though inefficient sleep after late-night eating could increase WASO and trigger compensatory increases in sleep duration.

10.
Hum Brain Mapp ; 41(12): 3186-3197, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32364670

RESUMO

General cognitive ability (GCA) refers to a trait-like ability that contributes to performance across diverse cognitive tasks. Identifying brain-based markers of GCA has been a longstanding goal of cognitive and clinical neuroscience. Recently, predictive modeling methods have emerged that build whole-brain, distributed neural signatures for phenotypes of interest. In this study, we employ a predictive modeling approach to predict GCA based on fMRI task activation patterns during the N-back working memory task as well as six other tasks in the Human Connectome Project dataset (n = 967), encompassing 15 task contrasts in total. We found tasks are a highly effective basis for prediction of GCA: The 2-back versus 0-back contrast achieved a 0.50 correlation with GCA scores in 10-fold cross-validation, and 13 out of 15 task contrasts afforded statistically significant prediction of GCA. Additionally, we found that task contrasts that produce greater frontoparietal activation and default mode network deactivation-a brain activation pattern associated with executive processing and higher cognitive demand-are more effective in the prediction of GCA. These results suggest a picture analogous to treadmill testing for cardiac function: Placing the brain in a more cognitively demanding task state significantly improves brain-based prediction of GCA.


Assuntos
Aptidão/fisiologia , Cognição/fisiologia , Rede de Modo Padrão/fisiologia , Função Executiva/fisiologia , Neuroimagem Funcional/métodos , Inteligência/fisiologia , Memória de Curto Prazo/fisiologia , Rede Nervosa/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Conectoma , Rede de Modo Padrão/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Modelos Teóricos , Rede Nervosa/diagnóstico por imagem , Testes Neuropsicológicos
11.
Mult Scler ; 26(11): 1437-1440, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31237825

RESUMO

BACKGROUND: Postoperative multiple sclerosis (MS) relapses are a concern among patients and providers. OBJECTIVE: To determine whether MS relapse risk is higher postoperatively. METHODS: Data were extracted from medical records of MS patients undergoing surgery at a tertiary center (2000-2016). Conditional logistic regression estimated within-patient unadjusted and age-adjusted odds of postoperative versus preoperative relapse. RESULTS: Among 281 patients and 609 surgeries, 12 postoperative relapses were identified. The odds of postoperative versus preoperative relapse in unadjusted (odds ratio (OR) = 0.56, 95% confidence interval (CI) = 0.18-1.79; p = 0.33) or age-adjusted models (OR = 0.66, 95% CI = 0.20-2.16; p = 0.49) were not increased. CONCLUSIONS: Surgery/anesthesia exposure did not increase postoperative relapse risk. These findings require confirmation in larger studies.


Assuntos
Anestesia , Esclerose Múltipla , Anestesia/efeitos adversos , Doença Crônica , Humanos , Razão de Chances , Recidiva , Estudos Retrospectivos , Fatores de Risco
12.
J Biomed Inform ; 106: 103428, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32339749

RESUMO

OBJECTIVE: Outpatient clinics lack infrastructure to easily measure and understand patient wait times. Our objective was to design a low-cost, portable passive real time locating system within an outpatient clinic setting to measure patient wait times and patient-provider interactions. MATERIALS AND METHODS: Direct observation was used to determine workflow in an outpatient glaucoma clinic at the University of Michigan. We used off-the shelf, antenna-integrated ultra-high frequency (UHF) RFID readers (ThingMagic, Astra-Ex, Woburn, MA) and UHF re-useable passive RFID tags (Zebra Impinj Monza 4QT, Seattle, WA). We designed a custom RFID management application in the Java programming language that was equipped with 'live' device administration to collect time and location data from patients and providers. These hardware choices enabled low cost system installation. Hidden Markov Modeling (HMM) was used to smooth patient and provider location data. Location data were validated against direct observations and EHR evaluation. RESULTS: The HMM smoothed RFID system data accurately predicted patient location 80.6% of the time and provider location 79.1% of the time, compared to direct observation locations, an improvement over the raw RFID location data (65.0% and 77.9% accurate, respectively). Patient process time was on average 42.8 min (SD = 27.5) and wait time was 47.9 min (SD = 33.1). The installation and recurring capital costs of the system are approximately 10% of available commercially-supplied patient/provider tracking systems. DISCUSSION: Passive RFID time study systems can enable real-time localization of people in clinic, facilitating continuous capture of patient wait times and patient-provider interactions. The system must be tailored to the clinic to accurately reflect patient and provider movement. CONCLUSIONS: Capturing wait time data continuously and passively can empower continuous clinical quality improvement initiatives to enhance the patient experience.


Assuntos
Dispositivo de Identificação por Radiofrequência , Sistemas Computacionais , Humanos , Listas de Espera , Fluxo de Trabalho
13.
Hepatology ; 68(3): 872-882, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29579356

RESUMO

Alcoholic cirrhosis (AC) is a major cause of liver-related morbidity and mortality in the United States. Rising rates of alcohol use disorders in the United States will likely result in more alcoholic liver disease. Our aim was to determine the prevalence, health care use, and costs of AC among privately insured persons in the United States. We collected data from persons aged 18-64 with AC (identified by codes from the International Classification of Diseases, Ninth and Tenth Revisions) enrolled in the Truven MarketScan Commercial Claims and Encounters database (2009-2015). We determined yearly prevalence, weighted to the national employer-sponsored, privately insured population. Using competing risk analysis, we estimated event rates for portal hypertensive complications and estimated the association between AC and costs as well as admissions and readmissions. In 2015, 294,215 people had cirrhosis and 105,871 (36%) had AC. Mean age at AC diagnosis was 53.5 years, and 32% were women. Over the 7 years queried, estimated national cirrhosis prevalence rose from 0.19% to 0.27% (P < 0.001) and for AC from 0.07% to 0.10% (P < 0.001). Compared to non-AC, AC enrollees were significantly more likely to have portal hypertensive complications at diagnosis and higher yearly cirrhosis and alcohol-related admissions (25 excess cirrhosis admissions and 6.3 excess alcohol-related admissions per 100 enrollees) as well as all-cause readmissions. Per-person costs in the first year after diagnosis nearly doubled for AC versus non-AC persons (US$ 44,835 versus 23,319). CONCLUSION: In a nationally representative cohort of privately insured persons, AC enrollees were disproportionately sicker at presentation, were admitted and readmitted more often, and incurred nearly double the per-person health care costs compared to those with non-AC. (Hepatology 2018).


Assuntos
Efeitos Psicossociais da Doença , Seguro Saúde , Cirrose Hepática Alcoólica/economia , Cirrose Hepática Alcoólica/epidemiologia , Adulto , Feminino , Humanos , Cirrose Hepática Alcoólica/terapia , Masculino , Pessoa de Meia-Idade , Prevalência , Estados Unidos/epidemiologia , Adulto Jovem
14.
Alcohol Clin Exp Res ; 43(2): 334-341, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30667521

RESUMO

BACKGROUND: The burden of alcohol-associated cirrhosis (AC) is high, and though alcohol cessation improves mortality, many patients fail to engage in alcohol use disorder (AUD) treatment and continue drinking. Our aim was to determine rates, predictors, and outcomes of AUD treatment utilization in AC patients with private insurance. METHODS: We collected data from persons with AC (diagnosed by ICD-9/ICD-10 codes), aged 18 to 64 years, enrolled in the Truven MarketScan Commercial Claims and Encounters database (2009 to 2016). We determined rates and predictors of substance abuse treatment visits as well as rates of alcohol relapse prevention medication prescriptions, weighted to the national employer-sponsored insured population. Effects of AUD treatment utilization on decompensation rates were calculated using proportional hazards regression with propensity score adjustment. RESULTS: A total of 66,053 AC patients were identified, 32% were female, and mean age at diagnosis was 54.5 years. About 72% had insurance coverage for substance abuse treatment. Overall, AUD treatment utilization rates were low, with only 10% receiving a face-to-face mental health or substance abuse visit and only 0.8% receiving a Food and Drug Administration (FDA)-approved relapse prevention medication within 1 year of index diagnosis. Women were less likely to receive a face-to-face visit (hazard ratio [HR] 0.84, p < 0.001) or an FDA-approved relapse prevention medication (0.89, p = 0.05) than men. AC patients who had a clinic visit for AUD treatment or used FDA-approved relapse medication showed decreased risk of decompensation at 1 year (HR 0.85, p < 0.001 for either). CONCLUSIONS: AUD treatment utilization is associated with lower decompensation rates among privately insured patients with AC. Women were less likely to utilize AUD treatment visits. Efforts to reduce gender-specific barriers to treatment are urgently needed to improve outcomes.


Assuntos
Seguro Saúde/estatística & dados numéricos , Cirrose Hepática Alcoólica/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Adulto , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Cirrose Hepática Alcoólica/complicações , Cirrose Hepática Alcoólica/prevenção & controle , Cirrose Hepática Alcoólica/terapia , Masculino , Pessoa de Meia-Idade , Prevenção Secundária/estatística & dados numéricos , Fatores Sexuais , Adulto Jovem
15.
Analyst ; 144(12): 3790-3799, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31116195

RESUMO

Herein we report the development of a cytometric analysis platform for measuring the contents of individual cells in absolute (picogram) scales; this study represents the first report of Raman-based quantitation of the absolute mass - or the total amount - of multiple endogenous biomolecules within single-cells. To enable ultraquantitative calibration, we engineered single-cell-sized micro-calibration standards of known composition by inkjet-printer deposition of biomolecular components in microarrays across the surface of silicon chips. We demonstrate clinical feasibility by characterizing the compositional phenotype of human skin fibroblast and porcine alveolar macrophage cell populations in the respective contexts of Niemann-Pick disease and drug-induced phospholipidosis: two types of lipid storage disorders. We envision this microanalytical platform as the foundation for many future biomedical applications, ranging from diagnostic assays to pathological analysis to advanced pharmaco/toxicokinetic research studies.

16.
Mol Pharm ; 15(12): 5454-5467, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30372084

RESUMO

The goal of this project was to explore and to statistically evaluate the responsible gastrointestinal (GI) factors that are significant factors in explaining the systemic exposure of ibuprofen, between and within human subjects. In a previous study, we determined the solution and total concentrations of ibuprofen as a function of time in aspirated GI fluids, after oral administration of an 800 mg IR tablet (reference standard) of ibuprofen to 20 healthy volunteers in fasted state conditions. In addition, we determined luminal pH and motility pressure recordings that were simultaneously monitored along the GI tract. Blood samples were taken to determine ibuprofen plasma levels. In this work, an in-depth statistical and pharmacokinetic analysis was performed to explain which underlying GI variables are determining the systemic concentrations of ibuprofen between (inter-) and within (intra-) subjects. In addition, the obtained plasma profiles were deconvoluted to link the fraction absorbed with the fraction dissolved. Multiple linear regressions were performed to explain and quantitatively express the impact of underlying GI physiology on systemic exposure of the drug (in terms of plasma Cmax/AUC and plasma Tmax). The exploratory analysis of the correlation between plasma Cmax/AUC and the time to the first phase III contractions postdose (TMMC-III) explains ∼40% of the variability in plasma Cmax for all fasted state subjects. We have experimentally shown that the in vivo intestinal dissolution of ibuprofen is dependent upon physiological variables like, in this case, pH and postdose phase III contractions. For the first time, this work presents a thorough statistical analysis explaining how the GI behavior of an ionized drug can explain the systemic exposure of the drug based on the individual profiles of participating subjects. This creates a scientifically based and rational framework that emphasizes the importance of including pH and motility in a predictive in vivo dissolution methodology to forecast the in vivo performance of a drug product. Moreover, as no extensive first-pass metabolism is considered for ibuprofen, this study demonstrates how intraluminal drug behavior is reflecting the systemic exposure of a drug.


Assuntos
Liberação Controlada de Fármacos , Jejum/fisiologia , Absorção Gastrointestinal/fisiologia , Trato Gastrointestinal/fisiologia , Ibuprofeno/farmacocinética , Administração Oral , Adulto , Área Sob a Curva , Disponibilidade Biológica , Variação Biológica Individual , Variação Biológica da População/fisiologia , Conjuntos de Dados como Assunto , Feminino , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Ibuprofeno/administração & dosagem , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Solubilidade , Comprimidos , Adulto Jovem
17.
Mol Pharm ; 15(12): 5468-5478, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30417648

RESUMO

Exploring the intraluminal behavior of an oral drug product in the human gastrointestinal (GI) tract remains challenging. Many in vivo techniques are available to investigate the impact of GI physiology on oral drug behavior in fasting state conditions. However, little is known about the intraluminal behavior of a drug in postprandial conditions. In a previous report, we described the mean solution and total concentrations of ibuprofen after oral administration of an immediate-release (IR) tablet in fed state conditions. In parallel, blood samples were taken to assess systemic concentrations. The purpose of this work was to statistically evaluate the impact of GI physiology (e.g., pH, contractile events) within and between individuals (intra and intersubject variability) for a total of 17 healthy subjects. In addition, a pharmacokinetic (PK) analysis was performed by noncompartmental analysis, and PK parameters were correlated with underlying physiological factors (pH, time to phase III contractions postdose) and study parameters (e.g., ingested amount of calories, coadministered water). Moreover, individual plasma profiles were deconvoluted to assess the fraction absorbed as a function of time, demonstrating the link between intraluminal and systemic behavior of the drug. The results demonstrated that the in vivo dissolution of ibuprofen depends on the present gastric pH and motility events at the time of administration. Both intraluminal factors were responsible for explaining 63% of plasma Cmax variability among all individuals. For the first time, an in-depth analysis was performed on a large data set derived from an aspiration/motility study, quantifying the impact of physiology on systemic behavior of an orally administered drug product in fed state conditions. The data obtained from this study will help us to develop an in vitro biorelevant dissolution approach and optimize in silico tools in order to predict the in vivo performance of orally administered drug products, especially in fed state conditions.


Assuntos
Liberação Controlada de Fármacos , Absorção Gástrica/fisiologia , Ibuprofeno/farmacocinética , Período Pós-Prandial/fisiologia , Estômago/fisiologia , Administração Oral , Adulto , Área Sob a Curva , Disponibilidade Biológica , Variação Biológica Individual , Variação Biológica da População/fisiologia , Simulação por Computador , Conjuntos de Dados como Assunto , Feminino , Interações Alimento-Droga/fisiologia , Esvaziamento Gástrico/fisiologia , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Ibuprofeno/administração & dosagem , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Solubilidade , Comprimidos , Adulto Jovem
18.
Pharm Res ; 36(1): 2, 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30402713

RESUMO

PURPOSE: To improve cytometric phenotyping abilities and better understand cell populations with high interindividual variability, a novel Raman-based microanalysis was developed to characterize macrophages on the basis of chemical composition, specifically to measure and characterize intracellular drug distribution and phase separation in relation to endogenous cellular biomolecules. METHODS: The microanalysis was developed for the commercially-available WiTec alpha300R confocal Raman microscope. Alveolar macrophages were isolated and incubated in the presence of pharmaceutical compounds nilotinib, chloroquine, or etravirine. A Raman data processing algorithm was specifically developed to acquire the Raman signals emitted from single-cells and calculate the signal contributions from each of the major molecular components present in cell samples. RESULTS: Our methodology enabled analysis of the most abundant biochemicals present in typical eukaryotic cells and clearly identified "foamy" lipid-laden macrophages throughout cell populations, indicating feasibility for cellular lipid content analysis in the context of different diseases. Single-cell imaging revealed differences in intracellular distribution behavior for each drug; nilotinib underwent phase separation and self-aggregation while chloroquine and etravirine accumulated primarily via lipid partitioning. CONCLUSIONS: This methodology establishes a versatile cytometric analysis of drug cargo loading in macrophages requiring small numbers of cells with foreseeable applications in toxicology, disease pathology, and drug discovery.


Assuntos
Macrófagos/efeitos dos fármacos , Análise Espectral Raman/métodos , Animais , Células Cultivadas , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Desenho de Equipamento , Citometria de Fluxo/métodos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Análise de Célula Única
19.
Paediatr Perinat Epidemiol ; 32(6): 504-511, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30266041

RESUMO

BACKGROUND: Sleep-disordered breathing (SDB) is linked to adverse pregnancy outcomes. However, little is known about the association of SDB with timing of delivery. We examined the association of snoring frequency, a key SDB marker, and snoring intensity, a correlate of SDB severity, with time-to-delivery among a cohort of pregnant women. METHODS: In this prospective cohort study, 1483 third trimester pregnant women were recruited from the University of Michigan prenatal clinics. Women completed a questionnaire about their sleep, and demographic and pregnancy information was abstracted from medical charts. After exclusion of those with hypertension or diabetes, 954 women were classified into two groups by their snoring onset timing, chronic or pregnancy-onset. Within each of these groups, women were divided into four groups based on their snoring frequency and intensity: non-snorers; infrequent-quiet; frequent-quiet; or frequent-loud snorers. Cox proportional hazard regression models were used to investigate the association between snoring frequency and intensity and time-to-delivery, adjusting for maternal characteristics. RESULTS: Chronic snoring was reported by half of the pregnant women, and of those, 7% were frequent-loud snorers. Deliveries before 38 weeks' gestation are completed occurred among 25% of women with chronic, frequent-loud snoring. Compared with pre-pregnancy non-snorers, women with chronic frequent-loud snoring had an increased hazard ratio for delivery (adjusted hazard ratio 1.60, 95% confidence interval 1.04, 2.45). CONCLUSIONS: Snoring frequency and intensity is associated with time-to-delivery in women absent of hypertension or diabetes. Frequent-loud snoring may have a clinical utility to identify otherwise low-risk women who are likely to deliver earlier.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Complicações na Gravidez/fisiopatologia , Síndromes da Apneia do Sono/fisiopatologia , Ronco/fisiopatologia , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações na Gravidez/epidemiologia , Resultado da Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Síndromes da Apneia do Sono/complicações , Síndromes da Apneia do Sono/epidemiologia , Ronco/epidemiologia , Ronco/etiologia , Fatores de Tempo
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