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A study was made to observe the association between the resistance to reinfection induced by irradiated metacercariae (MC) of Clonorchis sinensis and antigen specific Th1- and Th2-type cytokine productions in rats. Rats were infected with 20 MC of C. sinensis, previously exposed to a single dose of gamma irradiation, which varied from 0 to 100 Gy. All of them, single dose of 12 Gy showed higher IgG antibody titer with lowest worm recovery. Thus, 50 MC were used to challenge infection in rats previously infected with 20 MC irradiated at 12 Gy and the highest resistance to challenge infection was observed. The results of lymphocyte proliferation with specific antigen, ES Ag were shown no difference of proliferative responses as compared with primary and challenge infection at 12 Gy irradiation dose. In the case of cytokines production were observed that interferon (IFN-gamma) and interlukin (IL-2) were significantly enhanced, while IL-4 and IL-10 was almost unchanged to make comparison between primary and secondary infection at 12 Gy irradiation dose. In conclusion, the single dose of 12 Gy could be adopted for induction of the highest resistance to challenge infection. Up-regulation of Th1 type cytokines, IFN-gamma and IL-2 may be affected to develop vaccine by irradiated MC.

Relatively few studies have investigated peripheral sweating mechanisms of long-distance runners. The aim of this study was to compare peripheral sweating mechanisms in male long-distance runners, and sedentary counterparts. Thirty six subjects, including 20 sedentary controls and 16 long-distance runners (with 7-12 years of athletic training, average 9.2±2.1 years) were observed. Quantitative sudomotor axon reflex testing (QSART) with iontophoresis (2 mA for 5 min) and 10% acetylcholine (ACh) were performed to determine axon reflex-mediated and directly activated (DIR, muscarinic receptor) sweating. Sweat onset time, sweat rate, number of activated sweat glands, sweat output per gland and skin temperature were measured at rest while maximum oxygen uptake (VO2max) were measured during maximal cycling. Sweat rate, activated sweat glands, sweat output per gland, skin temperature and VO2max were significantly higher in the trained runners than in the sedentary controls. Sweat onset time was significantly shorter for the runners. In the group of long-distance runners, significant correlations were found between VO2max and sweat onset time (r2 = 0.543, P

Fibroblast growth factor 21 (FGF21) plays an important role in the regulation of energy homeostasis during starvation and has an excellent therapeutic potential for the treatment of type 2 diabetes in rodents and monkeys. Acute exercise affects glucose and lipid metabolism by increasing glucose uptake and lipolysis. However, it is not known whether acute exercise affects FGF21 expression. Here, we showed that serum FGF21 level is increased in mice after a single bout of acute exercise, and that this is accompanied by increased serum levels of free fatty acid, glycerol and ketone body. FGF21 gene expression was induced in the liver but not in skeletal muscle and white adipose tissue of mice after acute exercise, and further, the gene expression levels of hepatic peroxisome proliferator-activated receptor α (PPARα) and activating transcription factor 4 (ATF4) were also increased. In addition, we observed increased FGF21 level in serum of healthy male volunteers performing a treadmill run at 50 or 80% VO2max. These results suggest that FGF21 may also be associated with exercise-induced lipolysis in addition to increased catecholamines and reduced insulin.

Scaffolds were fabricated by electrospinning using polycaprolactone (PCL) blended with poly(methyl methacrylate) (PMMA) in ratios of 10/0, 7/3, 5/5 and 3/7. The PCL/PMMA ratio affected the fiber diameter, contact angle, tensile strength and biological in vitro and in vivo properties of the scaffolds, and the 7/3 ratio resulted in a higher mechanical strength than 5/5 and 3/7. In vitro cytotoxicity and proliferation of MG-63 osteoblast cells on these blended scaffolds were examined by MTT assay, and it was found that PCL/PMMA blends are suitable for osteoblast cell proliferation. Confocal images and expression of proliferating cell nuclear antigen confirmed the good proliferation and expression of cells on the 7/3 PCL/PMMA fibrous scaffolds. In vivo bone formation was examined using rat models, and bone formation was observed on the 7/3 PCL/PMMA scaffold within 2 months. In vitro and in vivo results suggest that 7/3 PCL/PMMA scaffolds can be used for bone tissue regeneration.

We investigated the sweating resp°nse during passive heating (partial submersi°n up t° the umbilical line in 42±0.5°C water, 30 min) after summer and winter seas°nal acclimatizati°n (SA). Testing was perf°rmed in July during the summer, 2011 [summer-SA; temp, 25.6±1.8°C; relative humidity (RH), 82.1±8.2%] and in January during the winter, 2012 (winter-SA; temp, -2.7±2.9°C; RH, 65.0±13.1%) in Che°nan (126°52'N, 33.38'E), Republic °f K°rea. All experiments were carried °ut in an aut°mated climatic chamber (temp, 25.0±0.5°C: RH, 60.0±3.0%). Fifteen healthy men (age, 23.4±2.5 years; height, 175.0±5.9 cm; weight, 65.3±6.1 kg) participated in the study. L°cal sweat °nset time was delayed during winter-SA c°mpared t° that after summer-SA (p<0.001). L°cal sweat v°lume, wh°le b°dy sweat v°lume, and evap°rative l°ss v°lume decreased significantly after winter-SA c°mpared t° th°se after summer-SA (p<0.001). Changes in basal metab°lic rate increased significantly after winter-SA (p<0.001), and tympanic temperature and mean b°dy temperature were significantly l°wer after summer-SA (p<0.05). In c°nclusi°n, central sud°m°t°r acitivity bec°mes sensitive t° summer-SA and blunt t° winter-SA in Rebubic °f K°rea. These results suggest that the b°dy adjusts its temperature by ec°n°mically c°ntr°lling the sweating rate but d°es n°t l°wer the thermal dissipati°n rate thr°ugh a m°re effective evap°rati°n scheme after summer-SA than that after winter-SA. [ABSTRACT FROM AUTHOR]

In this work, Simvastatin (SIM) loaded porous poly(lactic- co-glycolic acid) (PLGA) microspheres were fabricated using the W/O/W1/W2 double emulsion and solvent evaporation method. The optimal conditions for fabricating porous PLGA microspheres were determined to be 20% distilled water (v/v), 10% PLGA (m/v), and a 4:1 ratio of internal polyvinyl alcohol (PVA) to dichloromethane (DCM). The pores size distribution of porous PLGA microspheres was varied from 0.01 to 40 μm, while their particle displayed a bimodal size distribution that had two diameter peaks at around 100 μm and 500 μm. The SIM encapsulation efficacy was found to be very high with a yield near 80% and the porous PLGA microspheres showed the excellent biocompatibility. In addition, the drug release profile was found to be significantly different from a temporal basis. Base on the combined results of this study, SIM loaded PLGA microspheres holds great promise for use in biomedical applications, especially in drug delivery system or tissue regeneration. [ABSTRACT FROM AUTHOR]

Abstract  Natives of the tropics are able to tolerate high ambient temperatures. This results from their long-term residence in hot and often humid tropical climates. This study was designed to compare the peripheral mechanisms of thermal sweating in tropical natives with that of their temperate counterparts. Fifty-five healthy male subjects including 20 native Koreans who live in the temperate Korean climate (Temperate-N) and 35 native tropical Malaysian men that have lived all of their lives in Malaysia (Tropical-N) were enrolled in this study after providing written informed consent to participate. Quantitative sudomotor axon reflex testing after iontophoresis (2 mA for 5 min) with 10% acetylcholine (ACh) was used to determine directly activated (DIR) and axon reflex-mediated (AXR) sweating during ACh iontophoresis. The sweat rate, activated sweat gland density, sweat gland output per single gland activated, and oral and skin temperature changes were measured. The sweat onset time of AXR (nicotinic-receptor-mediated) was 56 s shorter in the Temperate-N than in the Tropical-N subjects (P P P P  [ABSTRACT FROM AUTHOR]

An optimization problem, formulated using a nonlinear least-squares approach, was used to estimate parameters for kinetic models of the three isoforms of the kidney-specific Na-K-2Cl (NKCC2) cotransporter. Specifically, the optimization problem estimates the magnitude of model parameters (i.e., off-binding and translocation rate constants) by minimizing the distance between model unidirectional fluxes and published unidirectional 86Rb+ uptake curves for the A, B, and F isoforms of the NKCC2 cotransporter obtained in transfected Xenopus oocytes. By using different symmetry assumptions, NKCC2 models with five, six, seven, or eight parameters were evaluated. The optimization method identified parameter sets that yielded computed unidirectional fluxes consistent with the uptake data. However, the parameter values were not unique, in that systematic exploration of the parameter space revealed alternative parameter sets that fit the data with similar accuracy. Finally, we demonstrate that the optimization method can identify parameter sets for the three transporter isoforms that differ only in ion binding affinities, a result that is consistent with a published mutagenesis analysis of the molecular and structural bases for the differences in 86Rb+ uptake among the A, B, and F isoforms. These NKCC2 cotransporter models will facilitate the development of larger scale models of ion transport by thick ascending limb cells. [ABSTRACT FROM AUTHOR]

Recent studies showed that tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), as well as high-sensitive C-reactive protein (hsCRP) levels are predictive factors of cardiovascular risk. However, the effect of cardiac rehabilitation (CR) intervention in coronary artery disease (CAD) patients on these factors is not known. The aim of this study was to evaluate the effects of CR and exercise on hsCRP and inflammatory cytokine levels in patients with CAD after percutaneous coronary intervention (PCI). CAD patients who underwent PCI were divided into a CR and exercise group (CRE, n = 29) or a control group (CON, n = 10). CR and exercise consisted of 6 weeks supervised exercise training and 8 weeks home-based, self-managed exercise. Compared to pre-experimental levels, TNF-α (by 20.4%; p = 0.006) and IL-6 (by 49.0%; p < 0.0001), as well as hsCRP (by 59.4%; p < 0.0001), were markedly decreased after CR and exercise in CAD patients but not in control group, except for IL-6 (by 41.6%; p = 0.001). However, there was no significant alteration of adiposity-related variables such as BMI, percent body fat, and waist circumferences, in both groups. We suggest that CR and exercise in CAD patients after PCI induce significant reduction in hsCRP and inflammatory cytokines (TNF-α and IL-6), and marked increase in exercise tolerance and capacity. [ABSTRACT FROM AUTHOR]

Tropical natives possess heat tolerance due to the ability to off-load endogenous and exogenous heat efficiently using a minimum amount of sweat. On the other hand, exposure of temperate natives to heat results in exaggerated production of sweat, of which part is lost by dripping and, thus, not available for evaporation. How sweating is modified in natives of temperate climate zones by prolonged residence in the tropics is not well-understood. The aim of this study was to investigate possible changes in the peripheral sweating mechanisms. Sweating responses to iontophoretically applied acetylcholine (ACh) were compared between Japanese subjects having either permanently resided in Japan (Japan resident Japanese, JRJ) or having stayed in the tropics for 2 years or longer (Tropics resident Japanese, TRJ). Quantitative sudomotor axon reflex tests by iontophoresis of ACh (10%, 2 mA for 5 min) were applied to determine directly activated (DIR) and axon reflex-mediated sweating during [AXR(1)] and after [AXR(2)] ACh iontophoresis. The sweat onset time of AXR(1) was 0.6 min shorter in JRJ than in TRJ (P<0.0001), and AXR(1) (P<0.0004), AXR(2) (P<0.0001), and DIR (P<0.0001) sweating responses were larger in JRJ than in TRJ. AXR and DIR sweating volumes (P<0.0001) were negatively correlated, and sweat onset times (P<0.0001) were positively correlated with the duration of residence in the tropics (2 to 13 years). The observed attenuation of sweating in TRJ suggests that temperate natives may acquire heat tolerance with improved sweating economy similar to tropical natives after prolonged residence in the tropics. [ABSTRACT FROM AUTHOR]

A nonlinear least-squares technique was applied to thermodynamically consistent kinetic (TCK) models for transport of ammonium by the NKCC2A cotransporter to identify model parameters that display typical ion binding kinetic curves. TCK models are needed to evaluate NKCC2 function when outside ion concentrations are sufficiently low to limit or reverse transport. Assuming equilibrium binding and asymmetry of the off-binding and translocation rate constants, the model consists of a system of 15 linear equations with 11 unknown parameters. One can reduce the number of unknown parameters by assuming symmetry of some parameters. Models with 7 to 11 parameters were considered. For each model the least-squares method was applied to identify parameter values which lead to kinetic curves in agreement with published binding kinetic data (Bergeron, et al, AJP 285: F68-F78, 2003 and Plata, et al, JBC 277:11004-11012, 2002). The models all predicted curves consistent with the binding data, and all exhibited proper behavior at very low ion concentrations. However, the model with highest binding symmetry showed smallest error and, thus, may be optimal. This approach provides a systematic means to obtain TCK models of cotransporters for use in models of epithelial cells. [ABSTRACT FROM AUTHOR]

A novel nanofiber membrane was fabricated by electrospinning composed of polyvinyl phosphonic acid (PVPA) and polyvinyl alcohol (PVA). Stabilization was done due to the high dissolvability of the membrane when in contact with water. Physical treatment was done by exposure to heat at 150°C in a vacuum environment at different periods of time. Chemical crosslinking was done by immersion inmethanol and methanol/ glutaraldehyde. A heat-exposed membrane was also further crosslinked chemically. All conditions were compared with regards to its effect on the material properties of the membranes and its biological response in vitro with MG-63 osteoblast-like cell line. Visual examination and dimensional analyses showed that heat treatment produced discoloration on the membrane surface and chemical crosslinking reduced membrane dimensions. Tensile strength and strain improved in crosslinked membranes compared to noncrosslinked counterpart. Swelling and degradation was also investigated and was seen to vary depending on the crosslinking condition. Biocompatibility was observed to be more favorable in heat-treated membranes. [ABSTRACT FROM AUTHOR]