Publications by authors named "Hays S"

A strategic and comprehensive program in which toxicokinetic (TK) measurements are made for all agrochemicals undergoing toxicity testing (both new compounds and compounds already registered for use) is described. This approach provides the data to more accurately assess the toxicokinetics of agrochemicals and their metabolites in laboratory animals and humans. Having this knowledge provides the ability to conduct more insightful toxicity studies, refine and interpret exposure assessments and reduce uncertainty in risk assessments.

View Article and Find Full Text PDF

The California Environmental Biomonitoring Program (also known as Biomonitoring California) has been generating human biomonitoring data and releasing it via their website. The current Biomonitoring California program is a collection of smaller studies, targeting specific populations (e.g.

View Article and Find Full Text PDF

Voriconazole is a triazole antifungal used to prevent and treat invasive fungal infections after lung transplantation, but it has been associated with an increased risk of developing cutaneous squamous cell carcinoma (SCC). Despite widespread use, there are no clear guidelines for optimal prophylactic regimens that balance the competing risks and benefits. We conducted a retrospective cohort study of all lung transplant recipients at the University of California, San Francisco, who were transplanted between October 1991 and December 2012 (n = 455) to investigate whether voriconazole exposure affected development of SCC, Aspergillus colonization, invasive aspergillosis and all-cause mortality.

View Article and Find Full Text PDF

Symbioses provide a way to surpass the limitations of individual microbes. Natural communities exemplify this in symbioses like lichens and biofilms that are robust to perturbations, an essential feature in fluctuating environments. Metabolic capabilities also expand in consortia enabling the division of labor across organisms as seen in photosynthetic and methanogenic communities.

View Article and Find Full Text PDF

Rationale: Frailty is associated with morbidity and mortality in abdominal organ transplantation but has not been examined in lung transplantation.

Objectives: To examine the construct and predictive validity of frailty phenotypes in lung transplant candidates.

Methods: In a multicenter prospective cohort, we measured frailty with the Fried Frailty Phenotype (FFP) and Short Physical Performance Battery (SPPB).

View Article and Find Full Text PDF

Background & Aims: Recent studies have suggested that the gut microflora has metabolic effects. We aimed to evaluate postnatal growth in preterm infants who received different probiotic supplements, and to assess the safety of probiotic administration.

Methods: This prospective, randomized, double-blind, controlled trial was performed at three tertiary care neonatal units.

View Article and Find Full Text PDF

Background: Successful lung transplantation for patients with pulmonary fibrosis from telomerase mutations may be limited by systemic complications of telomerase dysfunction, including myelosuppression, cirrhosis, and malignancy. We describe clinical outcomes in 14 lung transplant recipients with telomerase mutations.

Methods: Subjects underwent lung transplantation between February 2005 and April 2014 at 5 transplant centers.

View Article and Find Full Text PDF

Congenital disorders of glycosylation (CDG) are a group of inborn errors of metabolism presenting with heterogeneous multisystemic clinical manifestations. To date, more than 60 different types of CDG have been reported. ALG3-CDG is very rare, with only nine patients described so far.

View Article and Find Full Text PDF

Decisional involvement is widely recognized as an essential component of a professional nursing practice environment. In recent years, researchers have added to the conceptualization of nurses' role in decision-making to differentiate between the content and context of nursing practice. Yet, instruments that clearly distinguish between these two dimensions of practice are lacking.

View Article and Find Full Text PDF

Introduction: Idiopathic testicular/groin pain can be a difficult entity for children, their families, and caregivers. The role of interdisciplinary pain management has previously been demonstrated in treating chronic orchialgia at the present pediatric pain clinic.

Objective: To evaluate the role of interdisciplinary pain management in managing refractory orchialgia.

View Article and Find Full Text PDF

Traumatic Brain Injury (TBI) is one of the largest health problems in the United States, and affects nearly 2 million people every year. The effects of TBI, including weakness and loss of coordination, can be debilitating and last years after the initial injury. Recovery of motor function is often incomplete.

View Article and Find Full Text PDF

Exposure to fluoride is widespread due to its natural occurrence in the environment and addition to drinking water and dental products for the prevention of dental caries. The potential health risks of excess fluoride exposure include aesthetically unacceptable dental fluorosis (tooth mottling) and increased skeletal fragility. Numerous organizations have conducted risk assessments and set guidance values to represent maximum recommended exposure levels as well as recommended adequate intake levels based on potential public health benefits of fluoride exposure.

View Article and Find Full Text PDF

Heterochromatin and associated gene silencing processes play roles in development, genome defense, and chromosome function. In many species, constitutive heterochromatin is decorated with histone H3 tri-methylated at lysine 9 (H3K9me3) and cytosine methylation. In Neurospora crassa, a five-protein complex, DCDC, catalyzes H3K9 methylation, which then directs DNA methylation.

View Article and Find Full Text PDF

Background: Urinary analyte concentrations are affected both by exposure level and by urinary flow rate (UFR). Systematic variations in UFR with demographic characteristics or body mass index (BMI) could confound assessment of associations between health outcomes and biomarker concentrations.

Objectives: We assessed patterns of UFR (milliliters per hour) and body weight-adjusted UFR (UFRBW; milliliters per kilogram per hour) across age, sex, race/ethnicity, and BMI category in the NHANES (National Health and Nutrition Examination Survey) 2009-2012 data sets.

View Article and Find Full Text PDF

A number of biomonitoring surveys have been performed for chlorpyrifos (CPF) and its metabolite (3,5,6-trichloro-2-pyridinol, TCPy); however, there is no available guidance on how to interpret these data in a health risk assessment context. To address this gap, Biomonitoring Guidance Values (BGVs) are developed using a physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) model. The PBPK/PD model is used to predict the impact of age and human variability on the relationship between an early marker of cholinesterase (ChE) inhibition in the peripheral and central nervous systems [10% red blood cell (RBC) ChE inhibition] and levels of systemic biomarkers.

View Article and Find Full Text PDF

Since 2007, the Canadian Health Measures Survey (CHMS) has been collecting biomonitoring data from the general Canadian population and has provided, to date, nationally representative concentrations for hundreds of environmental biomarkers in blood or urine. Biomonitoring Equivalents (BEs) have been developed as tools to help interpret biomonitoring data in a health risk context at a population level. In this paper, BEs are used to relate biomonitoring data from the CHMS (2007-2011) to existing exposure guidance values developed by Health Canada and other government agencies.

View Article and Find Full Text PDF

Background: Hypersensitivity pneumonitis (HP) is an inhaled antigen-mediated interstitial lung disease (ILD). Advanced disease may necessitate the need for lung transplantation. There are no published studies addressing lung transplant outcomes in HP.

View Article and Find Full Text PDF

Current drinking water standards for chromium are for the combined total of both hexavalent and trivalent chromium (Cr(VI) and Cr(III)). However, recent studies have shown that Cr(III) is not carcinogenic to rodents, whereas mice chronically exposed to high levels of Cr(VI) developed duodenal tumors. These findings may suggest the need for environmental standards specific for Cr(VI).

View Article and Find Full Text PDF

Rationale: Obesity and underweight are contraindications to lung transplantation based on their associations with mortality in studies performed before implementation of the lung allocation score (LAS)-based organ allocation system in the United States Objectives: To determine the associations of body mass index (BMI) and plasma leptin levels with survival after lung transplantation.

Methods: We used multivariable-adjusted regression models to examine associations between BMI and 1-year mortality in 9,073 adults who underwent lung transplantation in the United States between May 2005 and June 2011, and plasma leptin and mortality in 599 Lung Transplant Outcomes Group study participants. We measured body fat and skeletal muscle mass using whole-body dual X-ray absorptiometry in 142 adult lung transplant candidates.

View Article and Find Full Text PDF

Background And Purpose: Vagus nerve stimulation (VNS) delivered during rehabilitative training enhances neuroplasticity and improves recovery in models of cortical ischemic stroke. However, VNS therapy has not been applied in a model of subcortical intracerebral hemorrhage (ICH). We hypothesized that VNS paired with rehabilitative training after ICH would enhance recovery of forelimb motor function beyond rehabilitative training alone.

View Article and Find Full Text PDF

The aim of the current HBM-study is to further the understanding of the impact of inter- and intra-individual variability in HBM surveys as it may have implications for the design and interpretation of the study outcomes. As spot samples only provide a snapshot in time of the concentrations of chemicals in an individual, it remains unclear to what extent intra-individual variability plays a role in the overall variability of population-wide HBM surveys. The current paper describes the results of an intensive biomonitoring study, in which all individual urine samples of 8 individuals were collected over a 6-day sampling period (a total of 352 unique samples).

View Article and Find Full Text PDF

Objective: Gross blood in stools is a peculiar entity in preterm infants, but little is known about its etiology. As gut microbiota can be distorted in preterm infants, we aimed to evaluate the gut microbiota in infants with gross blood in stools.

Study Design: In a prospective, controlled, single-center study, we enrolled all infants born before 34 weeks of gestational age presenting gross blood in stools that was either completely isolated or associated with mild clinical symptoms or radiological signs.

View Article and Find Full Text PDF

Traumatic brain injury (TBI) is one of the largest health problems in the United States and affects both cognitive and motor function. Although weakness is common in TBI patients, few studies have demonstrated a reduction in strength in models of brain injury. We have developed a behavioral method to measure volitional forelimb strength and quantify forelimb weakness following traumatic brain injury.

View Article and Find Full Text PDF

Selenium is an essential nutrient for human health with a narrow range between essentiality and toxicity. Selenium is incorporated into several proteins that perform important functions in the body. With insufficient selenium intake, the most notable effect is Keshan disease, an endemic cardiomyopathy in children.

View Article and Find Full Text PDF

Belatacept is a novel immunosuppressant that blocks a T-cell costimulation pathway and is approved for use in adult kidney transplant recipients. Its safety and efficacy have not been established after lung transplantation. We present a case of a lung transplant recipient treated with belatacept.

View Article and Find Full Text PDF