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1.
Assessment of sperm ubiquitination and DNA fragmentation as sperm functional markers are proposed to complement routine semen analysis. This study focuses on the evaluation of these markers in infertile men with varicocele or exposed to occupational background. The results were compared with normozoospermic men. Semen parameters in both groups were lower than those in the control group. Ubiquitination median, as a marker for functionality of the ubiquitin–proteasome system, was also lower in both groups. The ubiquitination median showed a significant positive correlation with motility in both groups, while it showed only a negative correlation with sperm morphology in the varicocele group. DNA fragmentation showed a significant correlation with semen parameters, in total varicocele and also total exposure groups. In conclusion, significant difference of sperm ubiquitination between normal and study groups further validates that sperm ubiquitination as a potential molecular marker for sperm evaluation in addition to routine semen analysis in clinical laboratories.  相似文献   
2.

Purpose  

The aim of this study was to investigate the survival and development of premature follicles and oocytes from a vitrified-transplanted ovary in a murine experimental model.  相似文献   
3.
Matrix metalloprotainases (MMPs) play an important role in several pathologic processes such as malignancy in which they facilitate invasion and metastasis and can be targets for anticancer therapies. Here, in this study, we investigated the cytotoxicity effect of Cousinia shulabadensis Attar & Ghahraman extract as well as its impact on MMPs activity using a model of cell line (Fibrosarcoma-Wehi164). To assess anti-invasiveness potentials, a modified zymoanalysis method was used to measure MMP-2 and MMP-9 activities in the conditioned-media. The concentration necessary to produce 50% cell death was >80µg/ml for ethanol extract of Cousinia shulabadensis, while a 23 µg/ml concentration of the diclofenac sodium produced the same effect. The invasion of WEHI 164 cells was considerably inhibited at concentrations > 20 µg/ml by total plant extract. The total extract of the plant did not show high toxicity at all tested concentrations, but demonstrated significant inhibition of MMP activity in dose-response fashion.  相似文献   
4.

Background and the purpose of the study

The species Hymenocrater calycinus, belongs to the plant family Lamiaceae and grows wildly in the north-east of Iran. Previously, the antimicrobial activity of the plant extracts was reported. In the present study, the bioactivity-guided fractionation of the methanol extract of H. calycinus and the combination effects of the isolated compound with cell wall active agents against S. aureus and E. coli was investigated.

Methods

Column and thin layer chromatographic methods were used for isolation and purification and spectroscopic data (MS, 1H- and 13C-NMR, HMQC, HMBC and 1H-1H COSY) were employed for identification of the compound isolated from the extract. A disk diffusion method was used to determine the antibacterial activity of the isolated compound against S. aureus and E. coli in comparison with 7 different antibiotics.

Results

The isolated compound 1 was identified as 3-(3, 4- dihydroxyphenyl) lactic acid 2-O-quinic acid. Compound 1 (500 µg/disc) enhanced antibacterial effect of ampicillin, ciprofloxacin, vancomycin and cefepime against S. aureus and activated the effects of ampicillin and vancomycin against E. coli.

Conclusion

Results showed that the compound 1 was not active against both tested strains at any concentration below 1 mg/disk, and as a result the enhancing effect of the compound could be due its association with antibiotics.  相似文献   
5.

Background and the purpose of the study

Selenium enriched Lactobacillus has been reported as an immunostimulatory agent which can be used to increase the life span of cancer bearing animals. Lactic acid bacteria can reduce selenium ions to elemental selenium nanoparticles (SeNPs) and deposit them in intracellular spaces. In this strategy two known immunostimulators, lactic acid bacteria (LAB) and SeNPs, are concomitantly administered for enhancing of immune responses in cancer bearing mice.

Methods

Forty five female inbred BALB/c mice were divided into three groups of tests and control, each containing 15 mice. Test mice were orally administered with SeNP-enriched Lactobacillus brevis or Lactobacillus brevis alone for 3 weeks before tumor induction. After that the administration was followed in three cycles of seven days on/three days off. Control group received phosphate buffer saline (PBS) at same condition. During the study the tumor growth was monitored using caliper method. At the end of study the spleen cell culture was carried out for both NK cytotoxicity assay and cytokines measurement. Delayed type hypersensitivity (DTH) responses were also assayed after 72h of tumor antigen recall. Serum lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) levels were measured, the livers of mice were removed and prepared for histopathological analysis.

Results

High level of IFN-γ and IL-17 besides the significant raised in NK cytotoxicity and DTH responses were observed in SeNP-enriched L. brevis administered mice and the extended life span and decrease in the tumor metastasis to liver were also recorded in this group compared to the control mice or L.brevis alone administered mice.

Conclusion

Our results suggested that the better prognosis could be achieved by oral administration of SeNP-enriched L. brevis in highly metastatic breast cancer mice model.  相似文献   
6.
In this study, 3-alkyl and 3-aryl esters of hexahydroquinoline derivatives were screened for their ability to decrease bacterial resistance to ciprofloxacin (CAS 85721-33-1), which is extensively used to treat bacterial infections. A group of 3-alkyl and 3-aryl esters of hexahydroquinoline derivatives in which 2-aryl thiazole is substituted at 4-position were synthesized. The enhancement of the antibacterial activity of ciprofloxacin by these new synthetic compounds was evaluated against a resistant clinical strain of Staphylococcus aureus. The agar disk diffusion method was used to determine the antibacterial activity of different synthetic compounds in the absence and presence of ciprofloxacin. These results indicate that the antibacterial effect of ciprofloxacin is enhanced by two 3-alkyl esters of hexahydroquinoline derivatives (7b-3 and 7b-4).The enhancing effect of 7b-4 on the antibacterial activity of ciprofloxacin was greater than that of compound 7b-3. In comparison to the other synthetic compounds, 7b-4 showed a 5.61-fold increase of the inhibition zone on the ciprofloxacin supplemented plates. The result demonstrated that compounds 7b (3 and 4) could serve as valuable probes to study the structure-function relationships of agents that reverse the resistance to ciprofloxacin.  相似文献   
7.
Our objectives were to assess sperm alteration and adipose tissue (AT) genes expression related to steroid metabolism subsequent to fatty acids consumption. Twenty‐nine mature male mice were divided into: fat diet (FD; n = 15) and the control group (n = 14). FD group was fed with low level of trans and saturated fatty acids source for 60 days. Sperm parameters, levels of hormones and the mRNA abundance of the target genes in AT were assessed. The sperm concentration, total and progressive motilities were lower in FD group compared to that of control (p < 0.01). Blood estradiol levels increased in FD (p < 0.001), whereas no significant difference was observed in testosterone. The mRNA levels of StAR, CYP11A1, CYP17A1, 17βHSD7 and 17βHSD12 in AT of FD were higher than those of the control (p < 0.05). In contrast, mRNA level of Cyp19a1 in FD was significantly (p < 0.05) lower than that of control. 17βHSD12 and 17βHSD7 (as oestrogenic genes) increased, while 17βHSD5 and 17βHSD3 (as androgenic genes) remained unchanged, indicating that dietary trans/saturated fatty acids affect AT genes expression. Probably, sperm parameters were altered by increment of expression level of genes involved in oestrogenic metabolism rather than those engaged in androgenic metabolism after fatty acids consumption.  相似文献   
8.
In the present research study, ciprofloxacin-coated zinc oxide nanoparticles were prepared using a precipitation method. The nature of interactions between zinc oxide nanoparticles and ciprofloxacin (CAS 85721-33-1) was studied by Fourier transform infrared spectroscopy. The results show that the carbonyl group in ciprofloxacin is actively involved in forming chemical--rather than physical--bonds with zinc oxide nanoparticles. Also the antibacterial activity of free zinc oxide nanoparticles and ciprofloxacin-coated zinc oxide nanoparticles have been evaluated against different clinical isolates of Staphylococcus aureus and Escherichia coli. The free zinc oxide nanoparticles did not show potent antibacterial activity against all test strains. In contrast, only the low concentrations of ciprofloxacin-coated zinc oxide nanoparticles (equivalent to the sub-minimum inhibitory concentrations of pure ciprofloxacin) considerably enhanced the antibacterial activity of zinc oxide nanoparticles against different isolates of Staphylococcus aureus and Escherichia coli (4 to 32 fold increase). The result is of particular value, since it demonstrates that, by using biocompatible zinc oxide nanoparticles in combination therapy, lower amounts of antibiotics may be needed.  相似文献   
9.
Although the incidence of ocular trauma has been clearly described in developed countries, few published data are available on the epidemiology and the effects of parameters that can influence the incidence and severity of ocular injuries in Iran. The present study tried to determine epidemiological aspects of ocular traumatic injuries and evaluate their effects on different types of ocular injury. The case series included 1950 consecutive patients with acute ophthalmic trauma presented to the emergency ward of Farabi Hospital in Tehran. Information was collected by interviewing patients and having them fill in a questionnaire. The final diagnosis was made by a medical resident. If there was a difficulty or doubt in diagnosis or classification, confirmation of diagnosis was made by senior faculty. Ocular injuries were classified into globe and non-globe injuries according to the site of injury. Mechanical globe injuries were classified according to Birmingham Eye Trauma Terminology (BETT) into closed and open injuries. The mean age of patients was 28.8 ± 12.8 years; 87.6% were male. The most common causes of injury were work-related (49.0%) and chance events (42.0%). The most frequent ocular injury was globe injury (95.6%), including mechanical (77.6% closed and 5.9% open), chemical (7.6%), photic (2.3%) and thermal (2.2%) injuries. Non-globe injury also occurred in 10.8% of patients; both globe and non-globe injuries occurred in 6.5% of patients. The hospitalization rate in all patients was 8.8%. Previous history of eye trauma was significantly more common in the group with isolated globe injuries (P < 0.001). History of eye trauma is a risk factor for globe injuries and female gender is a risk factor only for non-globe injuries. These two factors may predict future eye injury and increase its risk by 5.2 and 1.6 times, respectively.  相似文献   
10.
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