Human plasma leptin in obese subjects and diabetics

Leptin is the protein product of the ob gene, an adipocyte-specific gene, recently discovered in mice. Plasma leptin levels were determined in six normals, twenty-one subjects with impaired glucose tolerance, and forty-nine untreated NIDDM subjects. They increased with the augmentation of obesity (body mass index, BMI kg/m2) and were higher in females than in males: in BMI less than 25 kg/m2 the values of plasma leptin were 2.24 +/- 0.25 ng/ml (n=29) in males and 3.01 +/- 0.39 ng/ml (n=13) in females (P<0.054), respectively, in BMI between 25 kg/m2 and 30 kg/m2 they were 3.14 +/- 0.31 ng/ml (n=10) in males and 10.66 +/- 2.86 ng/ml (n=7) in females (P<0.0018) and in BMI higher than 30 kg/m2 their levels were 8.98 +/- 1.5 ng/ml (n=11) and 11.74 +/- 2.2 ng/ml (n=6) (P<0.23), respectively. The severity of diabetes mellitus judged from the fasting plasma glucose level had no influence on the plasma leptin levels during OGTT, but the leptin levels decreased significantly during a tolerance test (P<0.001), and similar results were also seen during a breakfast test. The fasting plasma leptin in the male with FBS less than 140 mg/dl had a significant correlation with the fasting plasma IRI level, but this correlation disappeared after taking obesity into consideration. Thus the plasma leptin was chiefly dependent on the body weight and gender and had no special relation to diabetic severity.     

Effect of exercise on tibial and lumbar vertebral bone mass in mature osteopenic rats: bone histomorphometry study

Tacrolimus (FK506) and cyclosporin A (CsA) are two potent immunosuppressants mainly metabolized by hepatic cytochrome P-450 3A (CYP3A) monooxygenase. The aim of this study was to compare the toxic effects of the two drugs on hepatocytes in primary culture as a function of their metabolism and to explore the variations of cytotoxicity when both drugs are associated. The cytotoxicity of FK506 and CsA, as expressed by their IC50 values, was of the same order but with a switch according to whether hepatocytes were induced or uninduced by dexamethasone, CsA being more toxic in its native form and FK506 through its metabolism. Similar results were obtained with the intracellular calcium content. When both drugs were associated at their IC50 values, the expected additive cytotoxic effect was not observed. Moreover, when small quantities of FK506 were added to CsA at its IC50, cell viability improved in the induced cultures. It is hypothesized that the interaction between the two drugs relies on a mechanism involving both competition of FK506 and CsA for CYP3A and of their immunophilin complexes for a common site on the calcineurin-calmodulin complex.     

Long-haul high-speed optical communication systems using asemiconductor laser amplifier

High-speed long-haul systems using semiconductor laser amplifiers, which eliminate the need for high-speed electronics in repeaters and are transparent to the transmission speed are considered for application in undersea high-speed transmission systems. The potential of laser-amplifier-repeated transmission systems has been explored by transmission experiments, showing that a high-speed system above 2 Gb is possible by filtering out the spontaneous emission power of the laser amplifier. A theoretical estimation of SNR degradation due to noise accumulation of chained laser amplifiers shows that systems are possible, using 30 to 40 laser amplifier repeaters, if narrow-bandwidth optical filters are used     

Mitral valve suturing technique. Needle grips of choice determined from a geometric basis

The paper aims at describing easy steps: asepsis and hygiene to prevent nosocomial infections within surgery unit in Hospitals with limited budget. Essential and compulsory they are: cleansing of the surgery unit before any disinfection, behaviour of the staff in relation to aerobic contamination, maintenance of equipment, prophylaxis applied to patients antibio-prophylaxis is also mentioned complementary to that steps. Possible strategies of fight and control are mentioned, including awareness and full participation of all.     

1.55-μm fiber-optic transmission experiments for long-spansubmarine cable system design

Results of 1.55-μm transmission experiments at 140, 280, and 565 Mb/s involving conventional and dispersion-shifted single-mode fibers along the Fabry-Perot laser diode (FP-LD) and distributed-feedback laser diode (DFB-LD) optical sources are discussed. The results show which combination of optical fiber and optical source best meet the requirement of long repeater spacing for each bit rate. The results indicate that to achieve repeater spacing more than 100 km with dispersion-shifted fibers and FP-LD optical sources will impose strict requirements on both the optical fibers and the optical sources even at 280 Mb/s. Alternatively, systems using DFB-LD optical sources will not degrade the transmission performances and will considerably loosen requirements on the fibers and optical sources. A combination of dispersion-shifted fibers and DFB-LD optical sources can further loosen the requirements on the fibers and optical sources in 560-Mb/s systems     

Antinociceptive effect of L-arginine in diabetic mice

The antinociceptive effect of L-arginine in streptozotocin-induced diabetic mice was examined. Although s.c. administration of L-arginine produced a dose-dependent inhibition of the tail-flick response in both non-diabetic and diabetic mice, the antinociceptive response was greater in diabetic mice than in non-diabetic mice. The antinociceptive effects of L-arginine in both diabetic and non-diabetic mice were significantly antagonized by s.c. administration of naltrindole, a selective delta-opioid receptor antagonist. However, neither beta-funaltrexamine, a selective mu-opioid receptor antagonist, nor nor-binaltorphimin ++, a selective kappa-opioid receptor antagonist, significantly affected the antinociceptive effect of L-arginine in diabetic and non-diabetic mice. These results suggest that L-arginine produces a marked antinociceptive effect in diabetic mice through the activation of delta-opioid receptors.