Changes in the local blood flows of the single kidney with partial impairment of the autonomic innervation

The changes of cortical and intramedullary blood flow of the remaining after nephrectomy kidney under the condition of guanethidine sympathectomy and continuous pharmacological blockade of parasympathetic mediation by atropine were studied in chronic experiments on Wistar line rats in dynamics at 4, 7, 15, 30, 60, 90 and 120 days. Decrease in cortical and increase of intramedullary peritubular blood flow were noted in both experimental series, that is both blockade of sympathetic and parasympathetic nerves after 15 days. The conclusion was made that blood flow redistribution is a universal mechanisms of single kidney adaptation to its neurogenic impairments.     

Adhesion of human granulocytes and T lymphocytes to vascular endothelial cells after stimulation with Bacteroides fragilis endotoxin and enterotoxin]

The aim of presented study was to estimates the number of human granulocytes and T lymphocytes adhering to 1 mm2 of vascular endothelial cell culture stimulated by Bacteroides fragilis endotoxins (LPS) and enterotoxin (BFT). HMEC-1 cells were activated with bacterial preparations at the concentration of 10 (micrograms/ml for 4 and 24 hours. Granulocytes and T lymphocytes were isolated from peripheral blood of healthy blood donors. The adhesion tests of granulocytes and adhesion tests of resting and activated with PMA (at the concentration of 10 ng/ml) T lymphocytes to the non-stimulated and stimulated by B. fragilis compounds (LPS and BFT) vascular endothelium were performed. The number of viable leukocytes, which adhered to the endothelium, was determined using inverted microscope (magnification 200x). The results were presented as the number of viable cells adhering to 1 mm2 of the endothelial cell culture. The results of experiments indicate that granulocytes and T lymphocytes (resting and after activation with PMA even in greater number) adhere to the endothelial cells stimulated by B. fragilis endotoxins and enterotoxin. B. fragilis toxins are weaker stimulants of human leukocyte adhesion to the HMEC-1 cells than E. coli O55:B5 LPS. B. fragilis LPS and BFT preparations stimulate endothelial cells to the adhesion of granulocytes in similar manner, whereas the activation of vascular endothelium to the adhesion of T lymphocytes is differentiated.     

Physical fitness in community‐dwelling older adults is linked to dietary intake,gut microbiota,and metabolomic signatures

When humans age, changes in body composition arise along with lifestyle‐associated disorders influencing fitness and physical decline. Here we provide a comprehensive view of dietary intake, physical activity, gut microbiota (GM), and host metabolome in relation to physical fitness of 207 community‐dwelling subjects aged +65 years. Stratification on anthropometric/body composition/physical performance measurements (ABPm) variables identified two phenotypes (high/low‐fitness) clearly linked to dietary intake, physical activity, GM, and host metabolome patterns. Strikingly, despite a higher energy intake high‐fitness subjects were characterized by leaner bodies and lower fasting proinsulin‐C‐peptide/blood glucose levels in a mechanism likely driven by higher dietary fiber intake, physical activity and increased abundance of Bifidobacteriales and Clostridiales species in GM and associated metabolites (i.e., enterolactone). These factors explained 50.1% of the individual variation in physical fitness. We propose that targeting dietary strategies for modulation of GM and host metabolome interactions may allow establishing therapeutic approaches to delay and possibly revert comorbidities of aging.     

Inhibition of Jack Bean Urease by 1,4-benzoquinone and 2,5-dimethyl-1,4-benzoquinone. Evaluation of the Inhibition Mechanism

1,4-benzoquinone (BQ) and 2,5-dimethyl-1,4-benzoquinone (DMBQ) were studied as inhibitors of jack bean urease in 50 mM phosphate buffer, pH 7.0. The mechanisms of inhibition were evaluated by progress curves studies and steady-state approach to data achieved by preincubation of the enzyme with the inhibitor. The obtained reaction progress curves were time-dependent and characteristic of slow-binding inhibition. The effects of different concentrations of BQ and DMBQ on the initial and steady-state velocities as well as the apparent first-order velocity constants obeyed the relationships of two-step enzyme-inhibitor interaction, qualified as mechanism B. The rapid formation of an initial BQ-urease complex with an inhibition constant of K i =0.031 mM was followed by a slow isomerization into the final BQ-urease complex with the overall inhibition constant of K*_i=4.5 × 10 ^?5 mM. The respective inhibition constants for DMBQ were K i =0.42 mM, K*_i =1.2 × 10 ^?3 mM. The rate constants of the inhibitor-urease isomerization indicated that forward processes were rapid in contrast to slow reverse reactions. The overall inhibition constants obtained by the steady-state analysis were found to be 5.1 × 10 ^?5 mM for BQ and 0.98 × 10 ^?3 mM for DMBQ. BQ was found to be a much stronger inhibitor of urease than DMBQ. A test, based on reaction with L-cysteine, confirmed the essential role of the sulfhydryl group in the inhibition of urease by BQ and DMBQ.     

Urine metabolomics analysis for adrenal incidentaloma activity detection and biomarker discovery

This study describes the development of a method suitable for the analysis of nineteen major urinary steroid metabolites in human urine. The analytes of interest were isolated from urine using solid phase extraction, subjected to enzymatic hydrolysis and again extracted applying solid phase extraction. After derivatization, methyloxime-trimethylsilyl ether derivatives of steroid hormones were identified by gas chromatography-mass spectrometry (GC/MS) and quantified by gas chromatography with flame ionization detector (GC/FID). The quantification method was validated for linearity, trueness, precision and selectivity. The limits of detection were between 6.2 and 7.2 ng/mL and limits of quantification were between 12.3 and 14.8 ng/mL. The established method was applied to analyze 28 urine samples from patients diagnosed with non-functioning adrenal incidentalomas (AIs) and 30 healthy subjects. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were employed to visualize the differences between metabolic profiles of patients and the control group and to determine possible markers of AIs activity. Both multivariate methods separated seven patients from the rest of the examined individuals. Five urinary metabolites including α-cortol, tetrahydrocorticosterone, tetrahydrocortisol, allo-tetrahydrocortisol and etiocholanolone were identified as potential biomarkers of pathological adrenal function. The altered metabolites reflected pathological metabolism mainly of cortisol and cortisone. This research proved that metabolomics is a suitable tool for disease research.     

Feeding Kinematics,Suction, and Hydraulic Jetting Performance of Harbor Seals (Phoca vitulina)

The feeding kinematics, suction and hydraulic jetting capabilities of captive harbor seals (Phoca vitulina) were characterized during controlled feeding trials. Feeding trials were conducted using a feeding apparatus that allowed a choice between biting and suction, but also presented food that could be ingested only by suction. Subambient pressure exerted during suction feeding behaviors was directly measured using pressure transducers. The mean feeding cycle duration for suction-feeding events was significantly shorter (0.15±0.09 s; P<0.01) than biting feeding events (0.18±0.08 s). Subjects feeding in-water used both a suction and a biting feeding mode. Suction was the favored feeding mode (84% of all feeding events) compared to biting, but biting comprised 16% of feeding events. In addition, seals occasionally alternated suction with hydraulic jetting, or used hydraulic jetting independently, to remove fish from the apparatus. Suction and biting feeding modes were kinematically distinct regardless of feeding location (in-water vs. on-land). Suction was characterized by a significantly smaller gape (1.3±0.23 cm; P<0.001) and gape angle (12.9±2.02°), pursing of the rostral lips to form a circular aperture, and pursing of the lateral lips to occlude lateral gape. Biting was characterized by a large gape (3.63±0.21 cm) and gape angle (28.8±1.80°; P<0.001) and lip curling to expose teeth. The maximum subambient pressure recorded was 48.8 kPa. In addition, harbor seals were able to jet water at food items using suprambient pressure, also known as hydraulic jetting. The maximum hydraulic jetting force recorded was 53.9 kPa. Suction and hydraulic jetting where employed 90.5% and 9.5%, respectively, during underwater feeding events. Harbor seals displayed a wide repertoire of behaviorally flexible feeding strategies to ingest fish from the feeding apparatus. Such flexibility of feeding strategies and biomechanics likely forms the basis of their opportunistic, generalized feeding ecology and concomitant breadth of diet.     

Patterns of Formation of the Fauna of Fleas (Siphonaptera) Parasitizing Mammals in the Stavropol Upland and Adjacent Territories

According to the recent data, 55 species of fleas parasitizing 65 species of mammals were recorded in the Stavropol Upland (central Ciscaucasia, Russia). The fauna of the region comprises 87% of the total species composition of Ciscaucasian fleas. Most of these species are widely distributed on the Caucasian Isthmus and also in the Eastern Mediterranean. Of them, 14 species are polyzonal, 14 mostly occur in forest-steppes, 7 in foreststeppes and steppes, 12 in steppes and semi-deserts, and 7 species occur in semi-deserts. According to paleogeographic reconstructions, in the Pliocene the Stavropol Upland was colonized by the flea species from the forest landscapes of Southern Europe and also of Southwest Asia and Asia Minor. Later, in the Pleistocene and Holocene, the Caucasian Isthmus continued to be colonized by mesophilous species from Southern Europe and by semi-desert species from Southern Siberia and the Turanian Province.