Effect of nitric oxide on exercise-induced proteinuria in rats.

Temporary proteinuria occurring after exercise is a common finding, and it is explained predominantly by alterations in renal hemodynamics. In this study, we investigated whether nitric oxide (NO), which is known to have an effect on renal hemodynamics and to increase during exercise, has a role in postexercise proteinuria. In the first step of this study, the effect of acute NO synthase blockage on exercise proteinuria was evaluated. The urinary protein levels in animals that performed acute exhaustive treadmill running exercise were considerably elevated compared with the control animals. Significantly elevated urinary protein levels were also detected in animals that received Nomega-nitro-L-arginine methyl ester before exhaustion, compared with both control and exhausted groups, and mixed-type proteinuria was detected in electrophoresis, as in all exhausted animals. In the second step of the study, a NO donor (isosorbide mononitrate) was given to rats 1 h before exhaustive exercise. Mixed-type proteinuria and the elevation in urinary protein levels that occur as a consequence of exhaustive exercise were prevented by NO donor treatment. Finally, in the third step of our study, a calcium channel blocker (diltiazem), another vasodilator, was applied to the rats 1 h before exhaustive exercise. Urinary protein levels were not different in exhausted rats with or without calcium channel blocker treatment. On the other hand, in both groups, urinary protein levels were higher than in the control group. The tail-cuff blood pressure alterations caused by vasodilator drug applications before exercise were not different for NO donor and calcium channel blocker groups. These results suggest that endogenous NO might prevent the postexercise proteinuria from becoming more severe by affecting hemodynamic changes that occur during exercise.     

Experimental and DFT computational studies on 5-benzyl-4-(3,4-dimethoxyphenethyl)-2H-1,2,4-triazol-3(4H)-one

The triazole compound, 5-benzyl-4-(3,4-dimethoxyphenethyl)-2H-1,2,4-triazol-3(4H)-one, has been synthesized and characterized by ¹H-NMR, ¹³C-NMR, IR, and X-ray single-crystal determination. The compound crystallizes in the monoclinic space group P2₁ with a?=?11.8844(3) Å, b?=?17.5087(4) Å, c?=?17.3648(6) Å, β?=?99.990(2)? and Z?=?8. In addition to the molecular geometry from X-ray experiment, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) ¹H- and ¹³C-NMR chemical shift values of the title compound in the ground state have been calculated using the density functional method (B3LYP) with 6-31G(d,p) basis set. The calculated results show that the optimized geometries can well reproduce the crystal structure and the theoretical vibrational frequencies and chemical shift values show good agreement with experimental ones. Besides, molecular electrostatic potential (MEP), natural bond orbital (NBO), and frontier molecular orbitals (FMO) analysis of the title compound were performed by the B3LYP/6-31G(d,p) method.     

Composition and the in vitro antimicrobial activities of the essential oils of some Thymus species

The genus Thymus (Lamiaceae) is represented by 38 species (64 taxa) in Turkey, and 24 of which are endemic to Turkey. Aerial parts of Thymus longicaulis subsp. chaubardii var. chaubardii, T. zygioides var. lycaonicus, T. longicaulis subsp. longicaulis var. subisophyllus and T. pulvinatus collected from three different localities in Balikesir province were subjected to hydrodistillation to yield essential oils which were subsequently analysed by GC and GC/MS. The main constituents of the oils were identified, and antimicrobial bioassay was applied. Thymol (56.6%, 42.8%, 36.9%) was the main component in the oils of T. longicaulis subsp. chaubardii var. chaubardii (chemotype I), T. longicaulis subsp. chaubardii var. chaubardii (chemotype II) and T. zygioides var. lycaonicus respectively. The oil of T. longicaulis subsp. longicaulis var. subisophyllus contained carvacrol (60.0%) and the oil of T. pulvinatus borneol (27.9%) as main constituents.     

Classroom Aids

Abstract

Ocone, Lynn The Youth Gardening Book Burlington, Vt.: Gardens for All (The National Assoc. for Gardening), 1983. Reviewed by Frances B. Spuler.

Ward, Alan A Source Book for Primary Science Education Kent, Eng.: Hodder &; Stoughton Educational, 1983 101 pp. hardcover. Reviewed by Julian R. Brandou.

Ward, Alan Tricks with Science, Words and Numbers London: Batsford Academic and Educational Ltd., 1983 96 pp. hardcover. Reviewed by Gerald R. Rising.

Robbins, R. Robert, and Hemenway, Mary Kay, with Jefferys, William H. Modern Astronomy: An Activities Approach Austin: University of Texas Press, 1982 257 pp. $17.50 paper Reviewed by Joseph S. Tenn.

Patterson, Walter C. Nuclear Power, 2d ed. New York: Penguin Books, 1983 219 pp. $4.95 paper Reviewed by Laurence A. Marschall.     

Pressure-related Increase of Asymmetric Dimethylarginine Caused by Hyperbaric Oxygen in the Rat Brain: A Possible Neuroprotective Mechanism

A decrease in nitric oxide availability in the brain tissue due to the inhibition of nitric oxide synthase (NOS) activity during the early phases of hyperbaric oxygen (HBO) exposure was found to be involved in hyperoxic vasoconstriction leading to reduced regional cerebral blood flow. We hypothesized that the concentration of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase (NOS), may be an important factor during this hyperoxic vasoconstriction state. Rats were exposed to 1, 2 and 3 atmospheres pure oxygen for two hours. A fourth group of animals served as control. Asymmetric dimethylarginine, L-Arginine and nitrite/nitrate (NO_x) concentrations were measured from deproteinized rat brain cytosols. In rat brains exposed to 3 atmospheres O₂, ADMA and L-Arginine levels were found to be significantly higher and NO_x significantly lower than control levels. Additionally, statistically significant correlations between ADMA and L-Arginine, and ADMA and NO_x concentrations were detected. In conclusion, this is the first study indicating increased ADMA levels in rat brains exposed to HBO. The simultaneously decreased NO_x values suggest that ADMA elevation resulted in NOS inhibition and therefore may be responsible for the early phase hyperoxic vasoconstriction.     

AZF microdeletions on the Y chromosome of infertile men from Turkey

Intervals V and VI of Yq11.23 regions contain responsible genes for spermatogenesis, and are named as "azoospermia factor locus" (AZF). Deletions in these genes are thought to be pathogenetically involved in some cases of male infertility associated with azoospermia or oligozoospermia. The aim of this study was to establish the prevalence of microdeletions on the Y chromosome in infertile Turkish males with azoospermia or oligozoospermia. We applied multiplex polymerase chain reaction (PCR) using several sequence-tagged site (STS) primer sets, in order to determine Y chromosome microdeletions. In this study, 61 infertile males were enrolled for the molecular AZF screening program. In this cohort, one infertile male had 46,XX karyotype and the remaining had 46,XY karyotypes. Forty-eight patients had a diagnosis of azoospermia and 13 had oligozoospermia. Microdeletions in AZFa, AZFb and AZFc (DAZ gene) regions were detected in two of the 60 (3.3%) idiopathic infertile males with normal karyotypes and a SRY translocation was determined on 46,XX male. Our findings suggest that genetic screening should be advised to infertile men before starting assisted reproductive treatments.     

Production and characterization of partially purified extracellular thermostable α-amylase by Bacillus subtilis in submerged fermentation (SmF)

A Bacillus strain was isolated from soil samples from the campus area of Dicle University. Based on 16S ribosomal RNA sequencing, the microorganism was closely related to Bacillus subtilis. Effects of different culture medium, incubation time, carbon and nitrogen sources, and various starches, flours, and chemicals on α-amylase production were examined. Maximum enzyme production (7516 U/mL) was obtained in a basal medium A containing 0.05% Tween 40 in 24 h. Partially purified enzyme showed maximum activity at 60 °C with an optimum pH of 6.0. The effects of 0.2% detergents (sodium dodecyl sulfate [SDS], CHAPS [3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate], and commercial detergent Omo Matic) on partially purified enzyme activity over a period of time (15-150 min) were examined and the order of inhibition effect from the most to the least was found as SDS > Omo Matic > CHAPS. Different metal ions inhibited α-amylase activity at low concentrations (1.5 mM). Co2? was a mild inhibitor and Hg2? and Cd2? were potent inhibitors, whereas Ca2? and Mg2? increased the enzyme activity. At 20 mM, Ca2? enhanced enzyme activity, and different Ca2? concentrations (10-300 mM) were studied.