The effect of potassium infusion on proximal sodium reabsorption and renin release in the dog

The effect of potassium infusion on proximal sodium reabsorption and renin release in the dog. The effect of infusions of potassium chloride (KC1) on sodium reabsorption by the proximal tubule and renal renin release was measured in 18 dogs. Following renal arterial infusions of 8 or 16 µEq/min/kg potassium chloride, fractional and absolute sodium reabsorption by the proximal tubule, measured by micropuncture techniques, was not significantly altered. As compared to five control dogs, urinary sodium excretion was significantly increased following both infusions of KC1. The release of renin was significantly decreased following both rates of potassium infusion. The inhibition of renin release was not associated with consistent changes in either glomerular filtration rate or renal plasma flow. The data indicate that the inhibition of renin release following the infusion of potassium is probably not the result of a marked increase in sodium delivery from the proximal tubule

PHOTOMETRY OF TYPE II CEPHEID CANDIDATES FROM THE ROTSE-I DEMONSTRATION PROJECT

We have obtained VR photometry of 205 Cepheid variable star candidates that were discovered in a small section of the Northern Sky Variability Survey. Given their locations and apparent magnitudes, any stars in this sample that are Cepheids are very likely to be type II Cepheids. On the basis of the regularity of variation, revised periods, light-curve morphology, slope of the color-magnitude relation, and color, we have identified 97 probable Cepheids and 17 possible Cepheids. While some of the photometric properties, particularly the colors, are consistent with the identification of these stars as Cepheids, the amplitudes are small compared to known type II Cepheids and the period distribution does not match that of known type II Cepheids. Three supplemental data tables are attached as supplemental files

Metals and metallothionein in the liver of raccoons: utility for environmental assessment and monitoring

The relationship between metallothionein levels and concentrations of several metals and radionuclides was examined in liver tissues of raccoons (Procyon lotor, n = 47) from the Department of Energy’s Savannah River Site in South Carolina to determine the applicability of metallothioneins as an initial screening device for exposure assessment in free-living mammals and environmental monitoring. Using a fluorescent marker and a cell sorter to measure metallothionein, a significant positive correlation was found across animals between levels of metallothioneins and concentrations of selenium (Pearson’s r = .30) , mercury (Pearson’s r = .31) , and copper (Pearson’s r = .30) in liver tissue. Arsenic, cobalt, silver, thallium, and tin were below detection limits in most or all liver samples. Other metals, including cadmium, chromium, radiocesium ( 137Cs) , copper, lead, manganese, strontium, and vanadium, showed only weak and nonsignificant correlations with metallothionein. Concentrations of mercury were correlated with concentrations of selenium (Pearson’s r = .73) , manganese (Pearson’s r = .56) , and strontium (Pearson’s r = .57). In an a posteriori test, there was a still unexplained positive correlation between mercury (Pearson r = .56) , selenium (Pearson r = .54) , and radiocesium (Pearson’s r = .38) concentrations and background cellular autofluorescence, and a negative correlation of strontium with the latter (Kendall tau = –.38) . Background cellular autofluorescence may represent a generalized cellular stress response, or a yet unidentified biomarker. To better understand which metals contribute to the induction of metallothionein, principle component analysis (PCA) was performed. The first three principle components explained 78% of the variance, with highest loadings being from mercury and radiocesium. Metallothionein levels did not correlate well with the principal components from the metals and radiocesium, while autofluorescent background levels tended to correlate better

Spatially Resolved Ultraviolet Spectroscopy of the Great Dimming of Betelgeuse

The bright supergiant, Betelgeuse (Alpha Orionis, HD 39801) experienced a visual dimming during 2019 December and the first quarter of 2020 reaching an historic minimum 2020 February 7$-$13. During 2019 September-November, prior to the optical dimming event, the photosphere was expanding. At the same time, spatially resolved ultraviolet spectra using the Hubble Space Telescope/Space Telescope Imaging Spectrograph revealed a substantial increase in the ultraviolet spectrum and Mg II line emission from the chromosphere over the southern hemisphere of the star. Moreover, the temperature and electron density inferred from the spectrum and C II diagnostics also increased in this hemisphere. These changes happened prior to the Great Dimming Event. Variations in the Mg II k-line profiles suggest material moved outwards in response to the passage of a pulse or acoustic shock from 2019 September through 2019 November. It appears that this extraordinary outflow of material from the star, likely initiated by convective photospheric elements, was enhanced by the coincidence with the outward motions in this phase of the $\sim$400 day pulsation cycle. These ultraviolet observations appear to provide the connecting link between the known large convective cells in the photosphere and the mass ejection event that cooled to form the dust cloud in the southern hemisphere imaged in 2019 December, and led to the exceptional optical dimming of Betelgeuse in 2020 February.Comment: 11 pages, 8 figures, Astrophysical Journal, accepte

Overlapping genetic susceptibility variants between three autoimmune disorders: rheumatoid arthritis, type 1 diabetes and coeliac disease

INTRODUCTION: Genome wide association studies, replicated by numerous well powered validation studies, have revealed a large number of loci likely to play a role in susceptibility to many multifactorial diseases. It is now well established that some of these loci are shared between diseases with similar aetiology. For example, a number of autoimmune diseases have been associated with variants in the PTPN22, TNFAIP3 and CTLA4 genes. Here we have attempted to define overlapping genetic variants between rheumatoid arthritis (RA), type 1 diabetes (T1D) and coeliac disease (CeD). METHODS: We selected eight SNPs previously identified as being associated with CeD and six T1D-associated SNPs for validation in a sample of 3,962 RA patients and 3,531 controls. Genotyping was performed using the Sequenom MassArray platform and comparison of genotype and allele frequencies between cases and controls was undertaken. A trend test P-value < 0.004 was regarded as significant. RESULTS: We found statistically significant evidence for association of the TAGAP locus with RA (P = 5.0 × 10-4). A marker at one other locus, C1QTNF6, previously associated with T1D, showed nominal association with RA in the current study but did not remain statistically significant at the corrected threshold. CONCLUSIONS: In exploring the overlap between T1D, CeD and RA, there is strong evidence that variation within the TAGAP gene is associated with all three autoimmune diseases. Interestingly a number of loci appear to be specific to one of the three diseases currently studied suggesting that they may play a role in determining the particular autoimmune phenotype at presentation

Su bstrate Specificity of Mam malian Folylpolyglutamate Synthetase for 5,1 0-Dideazatetrahydrofolate Analogs

SUMMARY The metabolism of 5,1 0-dideazatetrahydrofolate (DDATH

A Descriptive, Multiyear Examination of Positive Behavior Support

A major goal of positive behavior support (PBS) is to produce broad-based, long-term improvements in adaptive behavior; however, the empirical base, at present, is mainly composed of relatively short-term studies carried out in circumscribed contexts. Therefore, a need exists for reliable data that can inform the field regarding the comprehensive lifestyle effects of PBS implementation in natural community contexts over extended periods of time. The current investigation was conducted to provide a descriptive analysis of PBS with diverse participants and broad measurement strategies over multiple years. Using extensive data portfolios for 21 participants, we employed rating scales to quantify changes in key variables from baseline through 2 years of intervention. The data revealed variable levels of intervention integrity, generalized reductions in problem behavior with occasional relapses, and encouraging enhancements across six domains of quality of life. This study represents an initial attempt to understand the processes and outcomes of behavioral support by documenting behavioral patterns across full days, entire years, and all environments. We discuss the need to consider new conceptual and methodological frameworks for further study of efficacious and sustainable behavior support

Positive Behavior Support: Evolution of an Applied Science

Positive behavior support (PBS) is an applied science that uses educational and systems change methods (environmental redesign) to enhance quality of life and minimize problem behavior. PBS initially evolved within the field of developmental disabilities and emerged from three major sources: applied behavior analysis, the normalization/inclusion movement, and person-centered values. Although elements of PBS can be found in other approaches, its uniqueness lies in the fact that it integrates the following critical features into a cohesive whole: comprehensive lifestyle change, a lifespan perspective, ecological validity, stakeholder participation, social validity, systems change and multicomponent intervention, emphasis on prevention, flexibility in scientific practices, and multiple theoretical perspectives. These characteristics are likely to produce future evolution of PBS with respect to assessment practices, intervention strategies, training, and extension to new populations. The approach reflects a more general trend in the social sciences and education away from pathology-based models to a new positive model that stresses personal competence and environmental integrity