The isolated perfused kidney exhibits substantial charge selectivity, as in vivo, in relation to fractional clearance of [3H]dextran sulfate and [3H]dextran. When cycloheximide is present in perfusate, fractional clearance of dextran sulfate is increased and proteinuria becomes significant, but glomerular filtration rate remains essentially unchanged compared with control. The possible role of cells in affecting transglomerular transport was demonstrated when isolated glomeruli from control perfused kidneys showed a very significant resident concentration of [3H]dextran sulfate and [3H]albumin, whereas there was no corresponding accumulation of [3H]dextran or [3H]inulin. Glomerular concentration of dextran sulfate and albumin was significantly reduced by cycloheximide. Kinetics of uptake and release of glomerular dextran sulfate indicated that it had a half-life of glomerular residence of approximately 2-3 min and that this half-life was considerably extended in the presence of cycloheximide. The half-life for glomerular residence of albumin was in the range of 30-40 min. The conclusion from this work is that glomerular charge selectivity for dextran sulfate could be quantitatively rationalized on the basis of transient uptake and release by glomerular cells.

Aim:The rheological properties of erythrocytes are impaired in diabetes mellitus, especially because of changes in their membrane lipid composition.The aim of this study was to determine and examine the relationship between red blood cell (RBC) membrane and serum lipid composition in type II diabetes subjects with and without nephropathy.Methods:Trinidadian subjects aged 18–65 years were recruited for the study regardless of gender and ethnicity. Fasting blood samples were collected from 60 subjects of whom 20 were healthy individuals, 20 had type II diabetes without complications, and 20 were type II diabetics with nephropathy. Weight, height, waist/hip ratio, and blood pressure were recorded. All the blood samples were analysed to determine the serum lipid concentration, membrane lipid composition and plasma glucose concentration.Results:The body mass index and the systolic blood pressure of the diabetics (28.17 ± 4.98 kg/m2, 153.21 ± 22.10 mmHg) and those with nephropathy (25.87 ± 4.68, 158.60 ± 22.49 mmHg) were higher when compared with controls (24.67 ± 5.18, 119.15 ± 13.03 mmHg). The diabetic (175.89 ± 102.73 μg/mgprotein) and diabetic nephropathy (358.80 ± 262.66) subjects showed significantly higher levels of RBC membrane cholesterol compared with controls (132.27 ± 66.47). The membrane phospholipids, protein and Na+/K+ATPase concentrations were altered in diabetics and diabetic nephropathy patients when compared with controls. The trends of increased serum cholesterol and decreased high-density lipoprotein in diabetics and diabetic nephropathy patients were noted as compared with controls but they are not significant as expected. The low-density lipoprotein cholesterol was significantly higher in diabetics when compared with diabetic nephropathy and control subjects.Conclusions:Our data suggest that there is a relationship between RBC membrane and serum lipid composition in subjects with type II diabetes with and without nephropathy. This relationship shows that diet and lifestyle plays a significant role in the alterations of the lipids both in serum and RBC membrane. The membrane and serum lipid composition may be used as possible indicators for type II diabetic patients with and without nephropathy to control their diet in the beginning stages to prevent them from further complications.

No abstract

Background and Aims:Second-generation supraglottic airway devices are widely used in current anaesthesia practice. This randomised study was undertaken to evaluate and compare laryngeal mask airway: ProSeal laryngeal mask airway (PLMA), Supreme laryngeal mask airway (SLMA) and I-gel.Methods:Eighty-four adult patients undergoing elective surgery were randomly allocated to three groups: group P (PLMA), group I (I-gel) and group S (SLMA) of 28 patients each. Insertion times, number of insertion attempts, haemodynamic response to insertion, ease of insertion of airway device and gastric tube, oropharyngeal leak pressure (OLP) and pharyngolaryngeal morbidity were assessed. The primary outcome measure was the OLP after successful device insertion. Statistical analysis was performed using Statistical Package for the Social Sciences version 18.0 software using Chi-squared/Fisher's exact test (categorical data) and analysis of variance (continuous data) tests. P < 0.05 was considered statistically significant.Results:The demographic profile of patients was comparable. OLP measured after insertion, 30 minutes later and at the end of surgery differed significantly between the three groups (P < 0.001). The mean OLP was 32.64 ± 4.14 cm·H2O in group P and 29.79 ± 3.70 cm·H2O in group S. In group I, the mean OLP after insertion was 26.71 ± 3.45 cm H2O, which increased to 27.36 ± 3.22 cm H2O at 30 minutes and to 27.50 ± 3.24 cm H2O towards the end of surgery. However, these increases were not statistically significant (P = 0.641). Device insertion time was longest for group P (P = 0.001) and gastric tube insertion time was longest for group I (P = 0.001). Haemodynamic response to insertion and pharyngolaryngeal morbidity were similar with all three devices.Conclusion:PLMA provides better sealing pressure but takes longer to insert. I-gel and SLMA have similar sealing pressures. I-gel insertion time is quicker.

No abstract

Culture conditions that induce hepatic spheroidal aggregates sustain liver cells with metabolism that mimics in vivo hepatocytes. Here we present an array of elastin-like polypeptide conjugate coating materials (Aminated-ELPs) that are biocompatible, have spheroid-forming capacity, can be coated atop traditional culture surfaces, and maintain structural integrity while ensuring adherence of spheroids over long culture period. The Aminated-ELPs were synthesized either by direct conjugation of ELP and various polyelectrolytes or by conjugating both ELP and various small electrolytes to the reactive polymer poly(2-vinyl-4,4-dimethyl azlactone) (PVDMA). Spheroid morphology, cellular metabolic function, and liver-specific gene expression over the long-term, 20-day culture period were assessed through optical microscopy, measurement of total protein content and albumin and urea production, and quantitative real-time (qRT) PCR. We found that the amine content of the Aminated-ELP coatings dictated the initial hepatocyte attachment, but not the subsequent hepatocyte spheroid formation and their continued attachment. A lower amine content was generally found to sustain higher albumin production by the spheroids. Out of the 19 Aminated-ELP coatings tested, we found that the lysine-containing substrates comprising ELP-polylysine or ELP-PVDMA-butanediamine proved to consistently culture productive spheroidal hepatocytes. We suggest that the incorporation of lysine functional groups in Aminated-ELP rendered more biocompatible surfaces, increasing spheroid attachment and leading to increased liver-specific function. Taken together, the Aminated-ELP array presented here has the potential to create in vitro hepatocyte culture models that mimic in vivo liver functionality and thus, lead to better understanding of liver pathophysiology and superior screening methods for drug efficacy and toxicity. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 377-388, 2017.

No abstract

The version in the Kent Academic Repository may differ from the final published version. Users are advised to check http://kar.kent.ac.uk for the status of the paper. Users should always cite the published version of record.