Genetics and the microbiota Although it is well known that race and ethnicity are poor proxies for genetic ancestry, these factors may be somewhat correlated. ...host genetics may marginally ...contribute to racial/ethnic differences in gastrointestinal microbial composition and functionality. Periodontal disease may be attributable to complex and difficult-to-measure differences in socioeconomic and other social factors occurring over the life course that contribute to a lack of health care access and utilization. ...oral health metrics and their associated oral microbiota may be proxies for these complex exposures. ...the annual National Health and Nutrition Examination Survey (NHANES) ascertains the health and nutritional status of children and adults via questionnaires and biospecimen collection in a nationally representative sample of approximately 5000 individuals 13. Because of their oversampling of targeted groups of individuals, NHANES has become an invaluable resource for reliably estimating various US exposures, including those pertaining to social determinants of health. ...study populations like those represented in NHANES are particularly suitable for future collection of oral and fecal samples to characterize the gastrointestinal microbiota of a representative portion of the US population.
A measurement technique for identifying lee-side crossflow-induced boundary-layer separation on a blunt
7
∘
half-angle circular cone at high angle of attack has been developed and tested. Previous ...work has shown that local minima in root-mean-squared (rms) pressure fluctuations on the surface are good identifiers of separation. These surface pressure fluctuations are measured with a temperature-corrected, high-frequency-response anodized-aluminum pressure-sensitive paint (AA-PSP). This AA-PSP was made in-house to provide the high frequency response required for this work. The sensor’s frequency response of 3 kHz proved to be fast enough to detect lines of local minimum rms pressure fluctuations indicative of separation on the lee side of the cone for angles of attack from
9
.
8
∘
to
15
.
8
∘
. A shift in the separation location towards the windward side of the model was observed as angle of attack increased; however, the separation location converged to a constant azimuth for angles of attack greater than or equal to
1.8
×
the cone’s half angle.
As the U.S. Congress has steadily evolved since the Founding of our nation, so too has our understanding of the institution. The second edition of New Directions in Congressional Politics offers an ...accessible overview of the current developments in our understanding of America's legislative branch. Jamie L. Carson and Michael S. Lynch help students bridge the gap between roles, rules, and outcomes by focusing on a variety of thematic issues: the importance of electoral considerations, legislators' strategic behavior to accomplish objectives, the unique challenges of Congress as a bicameral institution in a polarized environment, and the often-overlooked policy outputs of the institution.
This book brings together leading scholars of Congress to provide a general overview of the entire field. Each chapter covers the cutting-edge developments on its respective topic. As the political institution responsible for enacting laws, the American public regularly looks to the U.S. Congress to address the important issues of the day. The contributors in this volume help explain why staying atop the research trends helps us better understand these issues in the ever-changing field of American politics.
New to the Second Edition
New and updated chapters highlighting party recruitment, redistricting, women in Congress, the nationalization of Congressional elections, and the reassertion of Congressional oversight.
A first look at Congressional-executive relations in the Trump era.
Updated data through the 2018 Midterm elections.
Healthcare workers (HCW) are presumed to be at increased risk of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection due to occupational exposure to infected patients. However, ...there has been little epidemiological research to assess these risks.
We conducted a prospective cohort study of HCW (n = 546) and non-healthcare workers (NHCW; n = 283) with no known prior SARS-CoV-2 infection who were recruited from a large U.S. university and two affiliated university hospitals. In this cross-sectional analysis of data collected at baseline, we examined SARS-CoV-2 infection status (as determined by presence of SARS-CoV-2 RNA in oropharyngeal swabs) by healthcare worker status and role.
At baseline, 41 (5.0%) of the participants tested positive for SARS-CoV-2 infection, of whom 14 (34.2%) reported symptoms. The prevalence of SARS-CoV-2 infection was higher among HCW (7.3%) than in NHCW (0.4%), representing a 7.0% greater absolute risk (95% confidence interval for risk difference 4.7, 9.3%). The majority of infected HCW (62.5%) were nurses. Positive tests increased across the two weeks of cohort recruitment in line with rising confirmed cases in the hospitals and surrounding counties.
Overall, our results demonstrate that HCW had a higher prevalence of SARS-CoV-2 infection than NHCW. Continued follow-up of this cohort will enable us to monitor infection rates and examine risk factors for transmission.
The relationship between clinical phenotype of childhood primary ciliary dyskinesia (PCD) and ultrastructural defects and genotype is poorly defined.
To delineate clinical features of childhood PCD ...and their associations with ultrastructural defects and genotype.
A total of 118 participants younger than 19 years old with PCD were evaluated prospectively at six centers in North America using standardized procedures for diagnostic testing, spirometry, chest computed tomography, respiratory cultures, and clinical phenotyping.
Clinical features included neonatal respiratory distress (82%), chronic cough (99%), and chronic nasal congestion (97%). There were no differences in clinical features or respiratory pathogens in subjects with outer dynein arm (ODA) defects (ODA alone; n = 54) and ODA plus inner dynein arm (IDA) defects (ODA + IDA; n = 18) versus subjects with IDA and central apparatus defects with microtubular disorganization (IDA/CA/MTD; n = 40). Median FEV1 was worse in the IDA/CA/MTD group (72% predicted) versus the combined ODA groups (92% predicted; P = 0.003). Median body mass index was lower in the IDA/CA/MTD group (46th percentile) versus the ODA groups (70th percentile; P = 0.003). For all 118 subjects, median number of lobes with bronchiectasis was three and alveolar consolidation was two. However, the 5- to 11-year-old IDA/CA/MTD group had more lobes of bronchiectasis (median, 5; P = 0.0008) and consolidation (median, 3; P = 0.0001) compared with the ODA groups (median, 3 and 2, respectively). Similar findings were observed when limited to participants with biallelic mutations.
Lung disease was heterogeneous across all ultrastructural and genotype groups, but worse in those with IDA/CA/MTD ultrastructural defects, most of whom had biallelic mutations in CCDC39 or CCDC40.
OleT is a cytochrome P450 enzyme that catalyzes the removal of carbon dioxide from variable chain length fatty acids to form 1-alkenes. In this work, we examine the binding and metabolic profile of ...OleT with shorter chain length (n ≤ 12) fatty acids that can form liquid transportation fuels. Transient kinetics and product analyses confirm that OleT capably activates hydrogen peroxide with shorter substrates to form the high-valent intermediate Compound I and largely performs C-C bond scission. However, the enzyme also produces fatty alcohol side products using the high-valent iron oxo chemistry commonly associated with insertion of oxygen into hydrocarbons. When presented with a short chain fatty acid that can initiate the formation of Compound I, OleT oxidizes the diagnostic probe molecules norcarane and methylcyclopropane in a manner that is reminiscent of reactions of many CYP hydroxylases with radical clock substrates. These data are consistent with a decarboxylation mechanism in which Compound I abstracts a substrate hydrogen atom in the initial step. Positioning of the incipient substrate radical is a crucial element in controlling the efficiency of activated OH rebound.
Multi-species assemblages can help identify key resources in their habitat by evaluating how they are partitioning their resources. Here we used the isotopic niche of loggerhead, Kemp’s ridley, and ...green sea turtles to assess their ecological niche within a Gulf of Mexico bay. Additionally, we assessed temporal and size-class variation in their diets by comparing the δ
13
C and δ
15
N values over various capture years and size classes. Based on the isotopic niche overlap results, interspecific competition occurs among loggerhead, Kemp’s ridley, and smaller green turtles. Green turtle and Kemp’s ridley diet varied by size class, while Kemp’s ridley diet also varied temporally. The three species partition resources by selecting different preferred diet items, although some overlap in diet, including between the herbivorous (green) and carnivorous (Kemp’s ridley, loggerhead) species, appears to occur. The high quality of this habitat may allow species co-existence and population recovery despite the possible use of shared resources.
The ambiguous effect of cultural distance on travel attitude and tourist behaviours has long been debated, but its implications are vital to the success of achieving a sustainable tourist-host ...relationship. The study explored the direct and indirect effects of perceived cultural distance on travel attitude by adopting a mixed-methods approach and introducing a multi-dimensional perspective regarding the tourists' social contact with the local. The mediating role of tourist-host social contact was also confirmed. The study found that the relationship between perceived cultural distance and travel attitude is "contact elastic". Results empirically support the co-existence of the paradoxical effects of cultural distance on travel attitude. Implications are provided to policy-makers, practitioners and local communities regarding achieving a sustainable tourist-host bond.
Chronic Kidney Disease (CKD) afflicts ~15% of U.S. adults and occurs when the kidneys are ineffective in filtering the blood of waste products. CKD is irreversible and current interventions are ...focused on protecting and preserving renal function. Risk factors for CKD are multifactorial but growing evidence suggest that a key risk factor is dietary salt intake. A diet high in sodium will increase fluid retention, blood pressure, proteinuria, and ultimately drive the progression of kidney damage. Currently, it is estimated that 90% of the U.S. population consumes excess dietary sodium. As such, it is a medical necessity that interventions focus on ways to optimize renal sodium excretion and protect kidney function over time.
Exercise is a key therapy to improve kidney function but a large amount of people are unable to exercise due to disability, lack of time or money, or a pandemic. Our lab has previously discovered that when myostatin, a negative regulator of skeletal muscle mass, is deleted from lean mice it also improves kidney function in diabetes. However, it is unknown whether myostatin deletion will also improve renal sodium handling. Thus, the hypothesis is that myostatin deletion improves sodium handling and protects against renal damage during a high salt diet.
The experiment used adult lean mice with and without myostatin constitutively deleted. Both groups of mice were placed on a high salt (HS) diet (4% NaCl) for 14 days. Food consumption, water intake, and urine production was assessed at baseline, acutely (first 3 days on HS diet) and at the end of the experiment using metabolic cages. Blood pressure studies (in vivo) are ongoing and markers of renal (dys)function are currently being assessed, along plasma hormones that regulate fluid balance. Significance was determined at P<0.05.
The results showed that myostatin deletion protects against kidney dysfunction during a high salt diet, as the myostatin KO mice consumed significantly more food, but maintained fluid balance (drank and urinated similar amounts to the lean control). Blood pressure remained lower in the myostatin KO compared to control. Importantly, myostatin deletion significantly blunted renal hypertrophy (68% less mass) compared to the control. Taken together, myostatin deletion improves the efficiency of the kidney in handling sodium and maintains fluid balance during a high salt diet. Thus, pharmaceutical inhibition of myostatin may prove an effective target for long‐term protection against high salt diets and preserving kidney function during CKD.
Primary ciliary dyskinesia is a genetically heterogeneous disorder of motile cilia. Most of the disease-causing mutations identified to date involve the heavy (dynein axonemal heavy chain 5) or ...intermediate(dynein axonemal intermediate chain 1) chain dynein genes in ciliary outer dynein arms, although a few mutations have been noted in other genes. Clinical molecular genetic testing for primary ciliary dyskinesia is available for the most common mutations. The respiratory manifestations of primary ciliary dyskinesia (chronic bronchitis leading to bronchiectasis, chronic rhino-sinusitis, and chronic otitis media)reflect impaired mucociliary clearance owing to defective axonemal structure. Ciliary ultrastructural analysis in most patients (>80%) reveals defective dynein arms, although defects in other axonemal components have also been observed. Approximately 50% of patients with primary ciliary dyskinesia have laterality defects (including situs inversus totalis and, less commonly, heterotaxy, and congenital heart disease),reflecting dysfunction of embryological nodal cilia. Male infertility is common and reflects defects in sperm tail axonemes. Most patients with primary ciliary dyskinesia have a history of neonatal respiratory distress, suggesting that motile cilia play a role in fluid clearance during the transition from a fetal to neonatal lung. Ciliopathies involving sensory cilia, including autosomal dominant or recessive polycystic kidney disease, Bardet-Biedl syndrome, and Alstrom syndrome, may have chronic respiratory symptoms and even bronchiectasis suggesting clinical overlap with primary ciliary dyskinesia.
PDF
