The role of intestinal bacteria in the ammonia detoxification ability of teleost fish.

Protein catabolism during digestion generates appreciable levels of ammonia in the gastrointestinal tract (GIT) lumen. Amelioration by the enterocyte, via enzymes such as glutamine synthetase (GS), glutamate dehydrogenase (GDH), and alanine and aspartate aminotransferases (ALT; AST), is found in teleost fish. Conservation of these enzymes across bacterial phyla suggests that the GIT microbiome could also contribute to ammonia detoxification by providing supplemental activity. Hence, the GIT microbiome, enzyme activities and ammonia detoxification were investigated in two fish occupying dissimilar niches: the carnivorous rainbow darter and the algivorous central stoneroller. There was a strong effect of fish species on the activity levels of GS, GDH, AST and ALT, as well as GIT lumen ammonia concentration, and bacterial composition of the GIT microbiome. Furthermore, removal of the intestinal bacteria impacted intestinal activities of GS and ALT in the herbivorous fish but not in the carnivore. The repeatability and robustness of this relationship was tested across field locations and years. Within an individual waterbody, there was no impact of sampling location on any of these factors. However, different waterbodies affected enzyme activities and luminal ammonia concentrations in both fish, while only the central stoneroller intestinal bacteria populations varied. Overall, a relationship between GIT bacteria, enzyme activity and ammonia detoxification was observed in herbivorous fish while the carnivorous fish displayed a correlation between enzyme activity and ammonia detoxification alone that was independent of the GIT microbiome. This could suggest that carnivorous fish are less dependent on non-host mechanisms for ammonia regulation in the GIT.

Evaluation of the bifactor structure of the dispositional hope scale.

The Dispositional Hope Scale (DHS; Snyder et al., 1991) is composed of items assessing an individual's perception of his or her agency and pathways. This study examined support for the bifactor structure and relation of the factors in this model with depressive symptoms. It also examined cross-gender measurement invariance for the bifactor model. A community sample of 413 women and 257 men completed the DHS. Confirmatory factor analysis indicated more support for the bifactor model than the 1- and 2-factor models. Results also indicated full measurement invariance across gender for the bifactor and the 2-factor models. The general and the specific agency factors, but not the specific pathways factor, correlated with depressive symptoms. The better support for the bifactor model suggests that ideally hope has to be measured and examined by factors reflecting high covariance for agency and pathways, and also factors reflecting unique variances for agency and pathways. The support for full cross-gender measurement invariance indicated that there are no differences in measurement and scaling properties for the DHS across ratings provided by women and men, and therefore the DHS ratings can be scored in the same way for women and men.

Travel medicine updates for the NP.

ABSTRACT: This article provides an overview of the approach to preparing patients for travel, including travel counseling and risk mitigation through vaccination and chemoprophylaxis. Although some patients require referral for consultation with a travel medicine specialist, others can be managed by their primary care provider. In this article, traveler's diarrhea, updated travel-related immunizations, and malaria prophylaxis are discussed.

Social support and sense of belonging as protective factors in the rumination-depressive symptoms relation among Australian women.

This study examined the applicability of the compensatory, risk-protective, and protective-protective models of resiliency to explain the association of depressive symptoms (outcome factor) with rumination (potential risk factor) and social support and sense of belonging (protective factors). A community sample of 179 Australian women between the ages of 18-64 participated. Results supported the compensatory models for both protective factors. Results did not support the risk-protective or protective-protective models. The results of this study indicate that interventions aimed at reducing depressive symptoms among women who ruminate should be focused on increasing either protective factor, and that little value is accrued in attempting to increase both protective factors.

Rural interhospital transfer of ST-elevation myocardial infarction patients for percutaneous coronary revascularization: the Stat Heart Program.

BACKGROUND: In Europe, interhospital transfer of ST-elevation myocardial infarction (STEMI) patients for primary percutaneous coronary intervention (PCI) from non-PCI-capable (STEMI-referral) to PCI-capable (STEMI-accepting) facilities has been shown to be a superior reperfusion strategy compared with on-site fibrinolysis. The feasibility of such programs in the United States remains poorly defined. METHODS AND RESULTS: We describe an observational cohort of 230 consecutive presumed STEMI patients who underwent interhospital transfer between January 2005 and March 2007 among 6 STEMI-referral and 2 STEMI-accepting hospitals in rural central Illinois. A standard treatment protocol using rapid interhospital transfer for primary PCI or rescue PCI after full-dose intravenous fibrinolysis (in event of unanticipated transfer delays) was initiated by the STEMI-referral emergency department physician. Three time intervals were evaluated: STEMI-referral care (door 1 to departure), transport time (door 1 departure to STEMI-accepting hospital arrival [door 2]), and STEMI-accepting hospital care (door 2 to balloon). Primary PCI was performed in 165 STEMI-confirmed patients (87.7%), whereas fibrinolysis was required in 16 patients (8.5%), with 56% undergoing rescue PCI. The median door 1-to-departure time was 46 minutes (25th and 75th percentiles, 32 and 62 minutes); approximately two thirds of this delay was attributable to the wait for transport arrival and departure. The transport and door 2-to-balloon times were 29 minutes (25th and 75th percentiles, 25 and 35 minutes) and 35 minutes (25th and 75th percentiles, 32 and 46 minutes), respectively. The door 1-to-balloon time was 117 minutes (25th and 75th percentiles, 98 and 137 minutes), with 12.2% and 58% of patients achieving a time of < or = 90 and < or = 120 minutes, respectively. No adverse clinical events occurred during interhospital transport. CONCLUSIONS: In rural US communities, emergency department physician-initiated interhospital transfer of STEMI patients for primary or rescue PCI is feasible and was safely executed with achievement of timely reperfusion when performed within coordinated healthcare networks.

Do You PrEP? A Review of Primary Care Provider Knowledge of PrEP and Attitudes on Prescribing PrEP.

Oral preexposure prophylaxis (PrEP) has been proven to be a safe and effective means of preventing HIV. The purpose of our literature review was to examine primary care provider knowledge and attitudes about prescribing PrEP. PubMed, CINAHL, Web of Science, and Scopus were searched and additional articles were identified through other sources, yielding 11 articles that met inclusion criteria. Overall, there was high variability among providers regarding attitudes, knowledge, and prescriptive practices related to PrEP. PrEP continues to be an underutilized HIV prevention intervention and more research focusing on provider-specific factors is warranted.

The interactive effect of digesting a meal and thermal acclimation on maximal enzyme activities in the gill, kidney, and intestine of goldfish (Carassius auratus).

Surrounding environmental temperatures affect many aspects of ectotherm physiology. Generally, organisms can compensate at one or more biological levels, or allow temperature to dictate processes such as enzyme activities through kinetic effects on reaction rates. As digestion also alters physiological processes such as enzyme activities, this study determined the interacting effect of thermal acclimation (8 and 20 °C) and digesting a single meal on maximal enzyme activities in three tissues of the goldfish (Carrassius auratus). Acclimation to elevated temperatures decreased branchial Na+, K+, ATPase (NKA) activity. In contrast, acclimation to elevated temperatures had no effect on citrate synthase (CS) or pyruvate kinase (PK) activity in any tissue, nor were renal NKA or glutamine synthetase (GS) activities impacted. Warm water-acclimation exaggerated the positive impact of digestion on intestinal and branchial NKA activities and intestinal GS activity only, but digestion had no effect in the kidney. CS and PK did not display intestinal zonation; however, there was a distinct increase towards the distal intestine in NKA and GS activities. Zonation of NKA was more prominent in warm-acclimated animals, while acclimation temperature did not affect intestinal heterogeneity of GS. Finally, the impact of tissue protein content on enzyme activity was discussed. We conclude that the intestine and gill of warm-acclimated goldfish exhibited an augmented capacity for increasing several enzyme activities in response to digestion while the kidney was unaffected by thermal acclimation or digesting a single meal. However, this amplified capacity was ameliorated by alterations in tissue protein content. Amplified increases in NKA activity may ultimately have implications for ATP demand in these tissues, while increased GS activity may beneficially increase ammonia-detoxifying capacity in the intestine.

Scattered Dose Calculations and Measurements in a Life-Like Mouse Phantom.

Anatomically accurate phantoms are useful tools for radiation dosimetry studies. In this work, we demonstrate the construction of a new generation of life-like mouse phantoms in which the methods have been generalized to be applicable to the fabrication of any small animal. The mouse phantoms, with built-in density inhomogeneity, exhibit different scattering behavior dependent on where the radiation is delivered. Computer models of the mouse phantoms and a small animal irradiation platform were devised in Monte Carlo N-Particle code (MCNP). A baseline test replicating the irradiation system in a computational model shows minimal differences from experimental results from 50 Gy down to 0.1 Gy. We observe excellent agreement between scattered dose measurements and simulation results from X-ray irradiations focused at either the lung or the abdomen within our phantoms. This study demonstrates the utility of our mouse phantoms as measurement tools with the goal of using our phantoms to verify complex computational models.

Preliminary comparison of quantity, quality, and microarray performance of RNA extracted from formalin-fixed, paraffin-embedded, and unfixed frozen tissue samples.

Microarrays have been used to simultaneously monitor the expression of thousands of genes from biological samples, an approach that can potentially uncover previously unrecognized functions of genes. Microarray analyses can rarely be conducted retrospectively because of the requirement for RNA to be obtained from fresh or unfixed frozen tissues. Archived pathology specimens would need to be used for retrospective analyses, and these are typically preserved as formalin-fixed, paraffin-embedded (FFPE) tissue. Formalin-fixed tissues have been shown to yield compromised RNA compared with that obtained from frozen tissue. To begin to assess the performance of RNA extracted from FFPE samples on a microarray format, we compared RNA from a model system of pelleted lipopolysaccharide-stimulated human bone marrow stromal cells that were snap frozen with RNA from FFPE cells. RNA integrity and Affymetrix quality control parameters were assessed, and differentially regulated genes were analyzed with Ingenuity Pathway Analysis software. Results demonstrate that both snap-frozen and FFPE samples yielded intact RNA suitable for amplification prior to Affymetrix GeneChip analysis. Although some transcriptional information was lost with RNA extracted from the FFPE samples, Ingenuity Pathway Analysis revealed that the major pathways identified as affected by drug treatment were similar. Results show that FFPE samples are amenable to Affymetrix GeneChip analysis, expanding the possibility for expression profiling on archived tissue blocks in pathology laboratories.

Gene expression profiling of RNA extracted from FFPE tissues: NuGEN technologies' whole-transcriptome amplification system.

Gene expression profiling of RNA isolated from formalin fixed, paraffin-embedded (FFPE) tissue samples has been historically challenging. Yet FFPE samples are sought-after because of the in-depth retrospective records typically associated with them rendering these samples a valuable resource for translational medicine studies. Extensive degradation, chemical modifications, and cross-linking have made it difficult to isolate RNA of sufficient quality required for large-scale gene expression profiling studies. NuGEN Technologies' WT-Ovation™ FFPE System linearly amplifies RNA from FFPE samples through a robust and simple whole-transcriptome approach using as little as 50 ng total RNA isolated from FFPE samples. The amplified material may be labeled with validated kits and/or protocols from NuGEN for analysis on any of the major gene expression microarray platforms, including: Affymetrix, Agilent, and Illumina gene expression arrays. Results compare well with those obtained using RNA from fresh-frozen samples. RNA quality from FFPE samples varies significantly and neither sample age nor sample size analysis via gel electrophoresis or the Agilent Bioanalyzer system accurately predict materials suitable for amplification. Therefore, NuGEN has validated a correlative qPCR-based analytical method for the RNA derived from FFPE samples which effectively predicts array results. The NuGEN approach enables fast and successful analysis of samples previously thought to be too degraded for gene expression analysis.

Plasmodium falciparum: hrp3 promoter region is associated with stage-specificity and episomal recombination.

The asexual blood stage of Plasmodium falciparum in the human host is comprised of morphologically distinct ring, trophozoite and schizont stages, each of which possesses a distinct pattern of gene expression. Episomal promoter recombination has been recently reported in malaria parasites. We aim to investigate the nature of this process, and its relationship with promoter activity by employing a series of nested deletions of the ring-specific hrp3 promoter. Our results showed a discrete promoter region that is preferentially used for recombination. The P. falciparum hrp3 mRNA is only seen in ring-stage parasites but deletion of the recombination region was associated with decreased ring-stage expression and concurrent detection of transcripts in trophozoite-stage parasites. Our results describe a ring-stage specific regulatory region possibly involved in episomal promoter recombination, suggesting that common sequences might mediate both processes.