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1.
Testicular torsion is a urological emergency referred to as 'acute scrotum', because inappropriate treatment can lead to male subfertility and infertility. A possible cause of testicular damage is the ischaemia-reperfusion (I/R) injury attributed to oxygen free radicals. L-carnitine, a vitamin-like antioxidant, plays a pivotal role in the maturation of spermatozoa within the reproductive tract. The aim of the present paper was to determine the protective effect of L-carnitine on testicular I/R-induced injury. Thirty-two male rats were divided into 4 groups (n = 8). Testicular torsion was created by rotating the right testis 720 degrees in a clockwise direction. Group 1: sham-operated control; group 2: ischaemia; group 3: I/R; group 4: ischaemia-L-carnitine treatment-reperfusion group. L-carnitine (500 mg kg(-1), intraperitoneally) was administered before 30 min of detorsion in Group 4. After torsion (5 h) and detorsion (5 h), bilateral orchidectomy was performed. The malondialdehyde (MDA) level was evaluated in testes. Histopathologically, Johnsen's spermatogenesis criteria and mean seminiferous tubule diameter (MSTD) measurements were used. Testicular MDA levels were higher in the torsion group compared to the sham-control group (p < 0.05). Detorsion (reperfusion) caused a further increase in MDA levels (p < 0.05). Pretreatment with L-carnitine prevented a further increase in MDA levels (p < 0.05). Histologically, torsion caused some separation among germinal cells in the seminiferous tubules, which became much more prominent in the I/R group but was attenuated with L-carnitine pretreatment. In conclusion, L-carnitine pretreatment may have a protective effect in experimental testicular torsion-detorsion model in rats by its well-known antioxidant potential.  相似文献   
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Sleep and Biological Rhythms -  相似文献   
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Heat stress compromises production, fertility, and health of dairy cattle. One mitigation strategy is to select individuals that are genetically resistant to heat stress. Most of the negative effects of heat stress on animal performance are a consequence of either physiological adaptations to regulate body temperature or adverse consequences of failure to regulate body temperature. Thus, selection for regulation of body temperature during heat stress could increase thermotolerance. The objective was to perform a genome-wide association study (GWAS) for rectal temperature (RT) during heat stress in lactating Holstein cows and identify SNPs associated with genes that have large effects on RT. Records on afternoon RT where the temperature-humidity index was ≥78.2 were obtained from 4,447 cows sired by 220 bulls, resulting in 1,440 useable genotypes from the Illumina BovineSNP50 BeadChip with 39,759 SNP. For GWAS, 2, 3, 4, 5, and 10 adjacent SNP were averaged to identify consensus genomic regions associated with RT. The largest proportion of SNP variance (0.07 to 0.44%) was explained by markers flanking the region between 28,877,547 and 28,907,154 bp on Bos taurus autosome (BTA) 24. That region is flanked by U1 (28,822,883 to 28,823,043) and NCAD (28,992,666 to 29,241,119). In addition, the SNP at 58,500,249 bp on BTA 16 explained 0.08% and 0.11% of the SNP variance for 2- and 3-SNP analyses, respectively. That contig includes SNORA19, RFWD2 and SCARNA3. Other SNPs associated with RT were located on BTA 16 (close to CEP170 and PLD5), BTA 5 (near SLCO1C1 and PDE3A), BTA 4 (near KBTBD2 and LSM5), and BTA 26 (located in GOT1, a gene implicated in protection from cellular stress). In conclusion, there are QTL for RT in heat-stressed dairy cattle. These SNPs could prove useful in genetic selection and for identification of genes involved in physiological responses to heat stress.  相似文献   
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Telomerase is one of the key enzymes responsible for the proliferative immortality of the majority of cancer cells. We recently introduced a new telomerase inhibitor, a 13-mer oligonucleotide N3' --> P5'-thio-phosphoramidate lipid conjugate, designated as GRN163L. This compound inhibits telomerase activity in various tumor cell lines with IC(50) values of 3-300 nM without any cellular uptake enhancers. GRN163L demonstrated potent and sequence specific anti-cancer activity in vivo in multiple animal models. This compound was able to significantly affect not only the growth of primary tumors, but also the spread and proliferation of metastases. GRN163L is currently in Phase I and Phase I/II clinical studies in patients with solid tumors and CLL, respectively.  相似文献   
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The Netherlands is "well known" for its nitrogen problems; it has one of the highest reactive nitrogen (Nr) emission densities in the world. It is a small country at the delta of several large European rivers. Ever since the industrial revolution, there has been a growing excess of nutrients and related emissions into the atmosphere (ammonia, nitrogen oxides and nitrous oxide) and into groundwater and surface water (nitrate), leading to a large range of cascading environmental impacts. Vehicular traffic, sewage and animal husbandry are the main sources of oxidized and reduced forms of Nr. This paper provides an overview of the origin and fate of nitrogen in the Netherlands, the various reported impacts of nitrogen, the Dutch and European policies to reduce nitrogen emissions and related impacts. In addition, ways are presented to go forward to potentially solve the problems in a European perspective. Solutions include the improvement of nitrogen efficiencies in different systems, technological options and education.  相似文献   
8.
Aim: This study was carried out to determine if there is any association between plasminogen activator inhibitor type-1 (PAI-1) gene 4G/5G polymorphism and plasma PAI-1 enzyme activity in acute stroke patients. Methods: In this study, 333 genomic DNAs (from 253 acute stroke patients and 80 healthy subjects) were analyzed. Genomic DNAs were prepared from peripheral blood using a saline method. These DNAs were amplified by PCR method using primers specific for 4G and 5G alleles. PCR products were separated by 2% agarose gel electrophoresis and visualized by a charge coupled device (CCD) camera. PAI-1 enzyme activities were measured by ELISA method. The results were evaluated statistically with Student's t-test, chi(2)-test, one-way analysis of variance, and stepwise regression analysis. Results: In this study, frequency of PAI-1 gene 4G5G genotype was found to be low both in patients and controls. PAI-1 enzyme activities were significantly increased in acute stroke patients compared to controls. Although PAI-1 gene 4G5G genotype frequencies were low, the patients carrying this allele had highest plasma PAI-1 enzyme activity; likewise, although PAI-1 gene 4G4G genotype frequencies were high, the patients carrying this allele had lowest plasma PAI-1 enzyme activities. Homocysteine levels had a positive effect of 65% on plasma PAI-1 enzyme activities. Conclusion: Consequently, in this study, we may assert that PAI-1 gene, 4G4G and 5G5G genotypes, PAI-1 activity, and homocysteine level determination are significant criteria for identifying patients who are likely to develop stroke; on the other hand, a direct relation does not exist between gene polymorphism and enzyme activity.  相似文献   
9.
Bladder carcinoma is the second most common genitourinary malignancy. Treatment options for bladder cancer include surgery, combined with chemotherapy, radiation, and/or immunotherapy. The adjuvant chemotherapy and immunotherapy regimen have been widely used in locally invasive as well as metastatic disease. The evaluation of new active agents with improved tolerability has been the focus of investigations over the past decade with minimal overall improvements in outcomes. Telomerase activity has been found in approximately 85-90% of all human tumors, but not in the majority of adjacent normal tissues. This suggests that telomerase may be an attractive target for the development of novel anticancer therapeutic agents. GRN163L is a lipid conjugated oligonucleotide N3' --> P5' thio-phosphoramidate, and is a potent telomerase RNA (hTR) template antagonist. In the present study, we show that the telomerase activity of T24-luc bladder cancer cells is inhibited by 1 microM GRN163L within 24 h of incubation. After two weeks of exposure to GRN163L, T24-luc cells became "clustered" whereas non-cancerous normal human uroepithelial cells were not morphologically affected. Moreover, in vitro GRN163L treated T24-luc bladder cancer cells entered G(0)/G(1) arrest following 2 weeks of continuous exposure and stopped dividing. Mismatch control compound had no effect on normal bladder epithelial cells or T24-luc cells. Additionally, a new generation of thio-phosphoramidate oligonucleotides were designed and tested in T24-luc cells and compared with GRN163L. The obtained results warrant further in vivo evaluation of GRN163L as a potential treatment for bladder cancer.  相似文献   
10.
Although the inguinal hernia is among the most commonly encountered and well-described health problems all over the world, the etiology is still controversial. The aim of this study was to compare the plasma and hernia sac tissue copper levels in direct and indirect inguinal hernia patients. Plasma and hernia sac tissue copper levels obtained from patients operated under spinal anesthesia with primary direct (group I, n = 55, 45 male, mean age = 45.68 yr) and indirect (group II, n = 55, 40 male, mean age = 38.57 yr) hernias were detected by atomic absorption spectrophotometer. Significantly lower plasma and hernia sac tissue copper levels were detected in group I in comparison to group II (p < 0.001). Both plasma and hernia sac tissue copper levels were significantly lower in males when we compare the patients according to their sex characteristics, including both direct and indirect hernia groups (p < 0.05 and p < 0.01, respectively). Age was not a significant factor. The plasma and hernia sac tissue copper levels were significantly lower in direct hernia patients in comparison to indirect hernia patients. Copper is a cofactor of lysyl oxidase, an important enzyme in collagen tissue metabolism, so there might be a defect in the collagen synthesis of direct hernia patients because of the decreased activity of the lysyl oxidase. Further investigations are necessary to clarify this concept.  相似文献   
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