The regulation of membrane 125I- and 86Rb+ permeability in a virally transformed cell line (NCL-SG3) derived from the human sweat gland epithelium

We have explored the factors that may regulate membrane permeability in a cell line (NCL-SG3) derived from the human sweat gland epithelium. Ionomycin increased the rate of 125I-efflux from preloaded cells and this action appeared to be due to an increase in intracellular free calcium ([Ca2+]i). The ionomycin-evoked increase in 125I- efflux was reduced in cells that were exposed either to barium or to valinomycin in the presence of a high concentration of external potassium. It thus appears that a fraction of the ionomycin-evoked increase in 125I- efflux is due to the activation of potassium channels and experiments using 86Rb+ also suggested that ionomycin increased the rate of potassium efflux, an effect which was totally abolished by barium. Blockade of Na(+)-K(+)-2Cl- cotransport and of Cl- -HCO3- exchange reduced the basal rate of 125I- efflux and the ionomycin-evoked increase in 125I-efflux from control cells and from cells depolarized by valinomycin. These transport systems thus contribute to anion efflux, although [Ca2+]i-dependent chloride channels also appear to be present. Acetylcholine increases [Ca2+]i in the secretory cells of human sweat glands, but this neurotransmitter did not increase [Ca2+]i in NCL-SG3 cells and so membrane permeability was not under cholinergic control. Adrenaline did not increase [Ca2+]i, but this hormone did evoke cyclic-3',5'-adenosine monophosphate (cyclic AMP) production. However, membrane permeability was not under adrenergic control, as the cells did not appear to express functional, cyclic AMP-dependent anion channels. This may be because they were not fully differentiated under the culture conditions. ATP consistently evoked a dose-dependent increase in anion efflux that appeared to be mediated by [Ca2+]i. The increase in [Ca2+]i was initiated by the release of calcium from a limited internal store and was subsequently sustained by calcium influx. UTP and ADP also increased [Ca2+]i, whereas adenosine, AMP and alpha,beta-methylene ATP were without effect. These data thus suggest that a subclass of type 2 purine receptor, which is functionally coupled to phosphoinositidase C, is present in these cells.     

Determining the optimal mix of exercise activities using mathematical programming

A 56K protein co-purified with bovine milk fat globule membrane (MFGM) proteins bound to Wisteria floribunda agglutinin (WFA) like most MFGM glycoproteins. Treatment with N-glycanase or beta-N-acetylhexosaminidase abolished the lectin binding to the protein. Amino acid sequence and immunoblot analyses revealed that the 56K protein is an IgG heavy chain. Lectin column chromatography of the oligosaccharides released by hydrazinolysis from the purified IgG heavy chains revealed that 0.08% of the total N-linked sugar chains bind to a WFA-agarose column, suggesting that they contain the beta-N-acetylgalactosaminylated structure.     

Effect of anesthesia and surgery on energy expenditure determined by indirect calorimetry in dogs with malignant and nonmalignant conditions

OBJECTIVE: To determine energy expenditure (EE) of apparently resting, client-owned dogs with malignant or nonmalignant diseases that were recovering from anesthesia and surgery, and compare those values with values from clinically normal, apparently resting, client owned dogs. ANIMALS: 40 apparently resting, client-owned dogs that had been given general anesthesia for various elective and nonelective surgical procedures, and 30 apparently resting, clinically normal client-owned dogs used as controls. PROCEDURE: EE was determined, using an open-flow indirect calorimetry system. Each dog was evaluated before and after surgery (0, 1, 2, and 3 days after surgery, then at suture removal > 14 days later) and compared with apparently resting, clinically normal, client-owned dogs (n = 30). Parameters evaluated were rate of oxygen consumption (Vo2/kg of body weight: ml/min/kg; Vo2/kg0.75: ml/min/kg0.75), EE (EE/kg: kcal/kg/d; EE/kg0.75: kcal/kg0.75/d), and respiratory quotient. RESULTS: Surgery and anesthesia did not significantly alter any of these parameters at any time assessed in any group. The pretreatment Vo2 and EE were significantly lower in the dogs with cancer, compared with dogs of other groups. CONCLUSIONS: These data suggest that the EE of a restricted group of dogs that undergo anesthesia and surgery for malignant and nonmalignant conditions does not increase from baseline values or when compared with values in clinically normal, client-owned dogs. CLINICAL RELEVANCE: This information may be of value when planning nutritional treatment for dogs recovering from anesthesia and surgery.     

Immediate management of posterior urethral disruptions due to pelvic fracture: therapeutic alternatives

PURPOSE: We retrospectively reviewed the results of 3 types of initial management of pelvic fracture urethral disruption in children. MATERIALS AND METHODS: From 1980 to 1994, 35 boys 2 to 15 years old (mean age 8.1) with prostatomembranous urethral disruption were treated, including 17 who also had associated injuries. Immediate treatment included suprapubic cystostomy and delayed urethroplasty in 19 patients (group 1), urethral catheter alignment without traction and concomitant suprapubic cystostomy in 10 (group 2), and primary retropubic anastomotic urethroplasty in 6 (group 3). RESULTS: In all patients in groups 1 and 2 severe urethral obliteration developed. Four group 3 patients (66%) had a stricture at the site of anastomotic repair. After delayed urethroplasty 16 group 1 (84%) and all 10 group 2 patients were continent. However, only 3 group 3 patients (50%) achieved continence. Retrospectively associated bladder neck injury occurred in 5 of the 6 incontinent boys. Erections were observed before and after treatment in all but 3 children. Unstable pelvic ring fractures (type IV) comprised 28% of all pelvic fractures with a high rate of associated injuries. CONCLUSIONS: As described, urethral alignment was not beneficial for avoiding urethral obliteration. Therefore we recommend suprapublic cystostomy as the only form of initial treatment in these cases. Urinary incontinence seems more likely related to associated bladder neck rupture and the severity of pelvic fracture rather than to initial treatment or delayed urethral repair. Consequently, when associated bladder neck injury is present, we advocate immediate surgical repair.     

Introduction to special section: Relapse to substance abuse: Recent findings from basic and clinical research.

A series of 6 articles concerning relapse to substance abuse and its treatment is introduced. Two articles review animal models of relapse and the potential role of drug priming effects, 2 articles present new data from experimental human research on cognitive and contextual determinants of relapse, while 2 articles describe clinical approaches and review the effectiveness of relapse prevention treatment. The series integrates clinical and basic research around a common theme and demonstrates that various types of research representing diverse perspectives are needed to understand this important feature of substance dependence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhalatory anesthetic (halothane) associated changes in the immune response in mice

The extent of surgery, the patient's age, health status and other factors may contribute to alteration of the immune system during anesthesia and surgery. In addition, inhalatory anesthetics may cause acute and chronic toxicity because of the production of intermediate and end metabolic compounds. The present work was undertaken to evaluate, both in vivo and in vitro, if repeated doses of halothane were able to affect the immune response in a murine model developed at our laboratory. Weekly doses of halothane were administered to mice subjected to no surgery and three days after the last anesthetic-exposure, several immunologic parameters were assessed. Results on the in vivo response to sheep red blood cells showed that halothane treatment increased the amount of specific antibody secreting B-cells, without affecting the delayed type hypersensitivity reaction to the same antigen. In vitro studies on spleen cell composition showed that halothane re-exposure diminished the number of CD4+, CD8+ and B-cells. Such changes were not translated into alterations on the mitogen-driven lymphoproliferation, as well as macrophage phagocytic and lytic functions. Our results indicate that halothane re-exposure is able to modulate the immune response affecting both the number of antibody secreting cells involved in a specific in vivo response, and the splenic lymphoid cell composition. Since such halothane-induced immune alterations might bias the results of a wide range of physiological research, even those involving other systems, a careful selection of the anesthetic agent and methods by which the compound is administered is advisable.     

A unified method for calculating the center of pressure during wheelchair propulsion

The measurement of the center of pressure (COP) has been and continues to be a successful tool for gait analysis. The definition of a similar COP for wheelchair propulsion. however, is not straightforward. Previously, a COP definition similar to that used in force plate analysis had been proposed. Unfortunately, this solution has the disadvantage of requiring a separate COP definition for each plane of analysis. A definition of the generalized center of pressure (GCOP) which is consistent in all planes of analysis is derived here. This definition is based on the placement of a force-moment system, equivalent to the force-moment system at the hub, on a line in space where the moment vector (wrench moment) is parallel to the force vector. The parallel force-moment system is then intersected with three planes defined by anatomical landmarks on the hand. Data were collected using eight subjects at propulsion speeds of 1.34 m/s and 2.24 m/s (1.34 m/s only for subject 1, 0.894 m/s and 1.79 m/s for subject 8). Each subject propelled a wheelchair instrumented with a SMARTwheel. A PEAK 5 video system was used to determine the position of anatomical markers attached to each subject's upper extremity. The GCOP in the transverse plane of the wrist formed clusters for all subject's except subject 2 at 1.34 m/s. The clustering of the GCOP indicates that the line of action for the force applied by the hand is approximately perpendicular to the transverse plane through the wrist. When comparing the magnitude of the moment vector part of the wrench with the moment of the force vector of the wrench about the hub, the wrench moment is approximately an order of magnitude smaller. This indicates that the role of the wrist for wheelchair propulsion is primarily to stabilize the force applied by the arm and shoulder.