12 research outputs found
Animal Models in Peritoneal Dialysis
Over the last decades peritoneal dialysis (PD) has become a successful and widely used treatment for endstage renal disease patients worldwide. Together with the increasing number of uremic patients successfully treated with PD has grown an interest in physiological, pathophysiological and clinical aspects of this therapeutic method. This article provides an overview of the current status on animal models used in studying the histology and physiology of the peritoneum, as well as the process of peritoneal dialysis itself. We discuss species of experimental animals, methods of peritoneal access, sampling for histology, different techniques and methodologies, and complications of experimental models of PD.
A Proper Motion Study of the Haro 6-10 Outflow: Evidence for a Subarcsecond Binary
We present single-dish and VLBI observations of an outburst of water maser
emission from the young binary system Haro 6-10. Haro 6-10 lies in the Taurus
molecular cloud and contains a visible T Tauri star with an infrared companion
1.3" north. Using the Very Long Baseline Array, we obtained five observations
spanning 3 months and derived absolute positions for 20 distinct maser spots.
Three of the masers can be traced over 3 or more epochs, enabling us to extract
absolute proper motions and tangential velocities. We deduce that the masers
represent one side of a bipolar outflow that lies nearly in the plane of the
sky with an opening angle of ~45\deg. They are located within 50 mas of the
southern component of the binary, the visible T Tauri star Haro 6-10S. The mean
position angle on the sky of the maser proper motions (~220\deg) suggests they
are related to the previously observed giant Herbig-Haro (HH) flow which
includes HH410, HH411, HH412, and HH184A-E. A previously observed HH jet and
extended radio continuum emission (mean position angle of ~190\deg) must also
originate in the vicinity of Haro6-10S and represent a second, distinct outflow
in this region. We propose that a yet unobserved companion within 150 mas of
Haro6-10S is responsible for the giant HH/maser outflow while the visible star
is associated with the HH jet. Despite the presence of H_2 emission in the
spectrum of the northern component of the binary, Haro6-10N, none of
outflows/jets can be tied directly to this young stellar object
Increased blood pressure in adult offspring of families with Balkan Endemic Nephropathy: a prospective study
BACKGROUND: Previous studies have linked smaller kidney dimensions to increased blood pressure. However, patients with Balkan Endemic Nephropathy (BEN), whose kidneys shrink during the course of the disease, do not manifest increased blood pressure. The authors evaluated the relationship between kidney cortex width, kidney length, and blood pressure in the offspring of BEN patients and controls. METHODS: 102 offspring of BEN patients and 99 control offspring of non-BEN hospital patients in the Vratza District, Bulgaria, were enrolled in a prospective study and examined twice (2003/04 and 2004/05). Kidney dimensions were determined using ultrasound, blood pressure was measured, and medical information was collected. The parental disease of BEN was categorized into three groups: mother, father, or both parents. Repeated measurements were analyzed with mixed regression models. RESULTS: In all participants, a decrease in minimal kidney cortex width of 1 mm was related to an increase in systolic blood pressure of 1.4 mm Hg (p = 0.005). There was no association between kidney length and blood pressure. A maternal history of BEN was associated with an increase in systolic blood pressure of 6.7 mm Hg (p = 0.03); paternal BEN, +3.2 mm Hg (p = 0.35); or both parents affected, +9.9 mm Hg (p = 0.002). There was a similar relation of kidney cortex width and parental history of BEN with pulse pressure; however, no association with diastolic blood pressure was found. CONCLUSION: In BEN and control offspring, a smaller kidney cortex width predisposed to higher blood pressure. Unexpectedly, a maternal history of BEN was associated with average increased systolic blood pressure in offspring
Odin observations of water in molecular outflows and shocks
Aims. We investigate the ortho-water abundance in outflows and shocks in
order to improve our knowledge of shock chemistry and of the physics behind
molecular outflows. Methods. We have used the Odin space observatory to observe
the H2O(110-101) line. We obtain strip maps and single pointings of 13 outflows
and two supernova remnants where we report detections for eight sources. We
have used RADEX to compute the beam averaged abundances of o-H2O relative to
H2. In the case of non-detection, we derive upper limits on the abundance.
Results. Observations of CO emission from the literature show that the volume
density of H2 can vary to a large extent, a parameter that puts severe
uncertainties on the derived abundances. Our analysis shows a wide range of
abundances reflecting the degree to which shock chemistry is affecting the
formation and destruction of water. We also compare our results with recent
results from the SWAS team. Conclusions. Elevated abundances of ortho-water are
found in several sources. The abundance reaches values as high as what would be
expected from a theoretical C-type shock where all oxygen, not in the form of
CO, is converted to water. However, the high abundances we derive could also be
due to the low densities (derived from CO observations) that we assume. The
water emission may in reality stem from high density regions much smaller than
the Odin beam. We do not find any relationship between the abundance and the
mass loss rate. On the other hand, there is a relation between the derived
water abundance and the observed maximum outflow velocity.Comment: 19 pages, 20 figures, 4 table
The evaluation of angiotensin-converting enzyme inhibitors in renal elimination with selected molecular descriptors
© 2017, University of Kragujevac, Faculty of Science. All rights reserved. Angiotensin-converting enzyme (ACE) inhibitors modulate the function of the renin-angiotensin-aldosterone system, and they are commonly prescribed antihypertensive drugs especially in patients with renal failure. In this study, the relationships between several molecular properties of eight ACE inhibitors (enalapril, quinapril, fosinopril, ramipril, benazepril, perindopril, moexipril, trandolapril) and their renal elimination data, from relevant literature, were investigated. The ’molecular descriptors of the ACE inhibitors, which included aqueous solubility data (logS); an electronic descriptor, polar surface area (PSA);, a constitutional parameter, molecular mass (Mr); and a geometric descriptor, volume value (Vol), as well as lipophilicity descriptors (logP values), were calculated using different software packages. Simple linear regression analysis showed the best correlation between renal elimination data and lipophilicity descriptor AClogP values (R2 = 0.5742). In the next stage of the study, multiple linear regression was applied to assess a higher correlation between the ACE inhibitors’ renal elimination data and lipophilicity, AClogP, with one additional descriptor as an independent variable. Good correlations were established between renal elimination data from the literature and the AClogP lipophilicity descriptor using the constitutional parameter (molecular mass (R2 = 0.7425)) or the geometric descriptor (volume value (R2 = 0.7224)) as an independent variable. The application of computed molecular descriptors in evaluating drug elimination is of great importance in drug research