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101.
Wiener Medizinische Wochenschrift - Infection prevention protocols are the accepted standard to control nosocomial infections. These protective measures intensified after the coronavirus 2019...  相似文献   
102.
Low-level laser therapy (LLLT) is a form of photon therapy which can be a non-invasive therapeutic procedure in cancer therapy using low-intensity light in the range of 450–800 nm. One of the main functional features of laser therapy is the photobiostimulation effects of low-level lasers on various biological systems including altering DNA synthesis and modifying gene expression, and stopping cellular proliferation. This study investigated the effects of LLLT on mice mammary tumor and the expression of Let-7a, miR155, miR21, miR125, and miR376b in the plasma and tumor samples. Sixteen mice were equally divided into four groups including control, and blue, green, and red lasers at wavelengths of 405, 532, and 632 nm, respectively. Weber Medical Applied Laser irradiation was carried out with a low power of 1–3 mW and a series of 10 treatments at three times a week after tumor establishment. Tumor volume was weekly measured by a digital vernier caliper, and qRT-PCR assays were performed to accomplish the study. Depending on the number of groups and the p value of the Kolmogorov-Smirnov test of normality, a t test, a one-way ANOVA, or a non-parametric test was used for data analyses, and p?<?0.05 was considered to be statistically significant. The average tumor volume was significantly less in the treated blue group than the control group on at days 21, 28, and 35 after cancerous cell injection. Our data also showed an increase of Let-7a and miR125a expression and a decrease of miR155, miR21, and miR376b expression after LLLT with the blue laser both the plasma and tumor samples compared to other groups. It seems that the non-invasive nature of laser bio-stimulation can make LLLT an attractive alternative therapeutic tool.  相似文献   
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Introduction: There are some evidences indicating DNA damage by oxidant and mutant agents has an essential role in the chronic renal failure and end stage renal disease (ESRD). To investigate the possible association of GSTs variants with ESRD, we investigated the frequency of GST- T1, M1, and P1 genotypes, and the level of malondialdehyde (MDA) in patients with ESRD.

Materials and methods: The present case-control study consisted of 136 ESRD patients treated with maintenance hemodialysis and 137 gender- and age-matched, unrelated healthy controls from the population of west of Iran. The GST- T1, M1, and P1 genotypes were determined in all individuals using multiplex-PCR and PCR-RFLP. The level of MDA was measured by high-performance liquid chromatography (HPLC).

Results: We found that GSTM1 and GSTT1 null genotypes (GSTT1?/GSTM1?) increased the risk of ESRD by 1.8 times (p?<?0.001) and the increased risk of ESRD for GSTM-null (T1+-M1?) genotype was 3.04 times (p?=?0.002). ESRD patients carriers the GST (GSTM1-null?+?GSTT1-null?+?GST-null) genotypes compared to GST normal genotype increased the risk of ESRD by 3.3 (p?<?0.001) times. ESRD patients carriers of GST-null, GSTM1-null, and GSTT1-null genotypes had greater MDA concentration compared with the same genotypes of control subjects. Our results indicated that the GST-null allele (GSTT1-null/GSTM1-null) is a risk factor for ESRD and carriers of this allele have high levels of MDA.

Conclusion: Our findings indicate that oxidative stress, impairment of the antioxidant system and abnormal lipid metabolism may play a role in the pathogenesis and progression of ESRD and its related complications. These data suggest that patients with ESRD are more susceptible to vascular diseases.  相似文献   
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Background

Colitis, a colonic inflammatory condition, showed a linkage with hepatobiliary disorders such as cirrhosis. It has been reported that both endogenous opioids and nitric oxide (NO) play critical roles in colitis pathogenesis. Moreover, opioid and NO levels showed elevation in patients with cirrhosis. The aim of this study was to evaluate the effect of cirrhosis on the experimental model of colitis and the possible involvement of opioidergic/nitrergic systems in rats.

Methods

Colitis was induced by acetic acid 28 days after bile duct ligation (BDL). L-NAME, as an inhibitor of NO synthase and naltrexone, as an antagonist of opioid receptors were administered intraperitoneally to animals during 3 days after induction of colitis. Macroscopic colitis lesion area, inflammatory mediators change, NO metabolite levels, and colon microscopic injuries were assessed 3 days after induction.

Results

Cirrhosis significantly reduced the severity of damages to the colon. Administration of L-NAME (10 mg/kg), naltrexone (10 mg/kg) and co-administration of L-NAME (1 mg/kg) and naltrexone (5 mg/kg) significantly decreased the protective effect of BDL on colitis. Nitrite elevated levels in BDL rats were significantly diminished in L-NAME- and naltrexone-treated animals. Histopathology parameters and cytokines level alterations in the colon of acetic acid-treated animals after BDL was reversed after injection of L-NAME, naltrexone, and co-administration of L-NAME (1 mg/kg) + naltrexone (5 mg/kg).

Conclusion

Cirrhosis improved the intestinal damages induced by acetic acid in rats which may be mediated through interaction of nitrergic and opioidergic systems.  相似文献   
109.
Brain Imaging and Behavior - The pathophysiology of migraine as a headache disorder is still undetermined. Diffusion tensor imaging (DTI) has significantly improved our knowledge about brain...  相似文献   
110.
Testicular torsion is a serious urological disease leading to testicular damage. This study aimed to assess the effect of minocycline on testicular ischaemia/reperfusion (I/R) injury caused by testicular torsion/detorsion. Male adult Wistar rats (n = 32) were assigned into four groups of sham, I/R, I/R + minocycline and minocycline. I/R injury was induced by two sets of surgical operations, including the rotation of the left testis (720°, counterclockwise), followed by detorsion after 4 hr. The administration of minocycline was carried out 30 min before detorsion and then continued for 8 weeks. At the end of the 8th week, rats were killed and sampling was done. Johnson's score, the height of seminiferous tubule epithelium, the mean seminiferous tubule diameter, as well as biochemical parameters, SOD, GPx and CAT, were significantly enhanced in the I/R + minocycline group compared with the I/R group. The administration of minocycline led to a marked decrease in expression levels of Caspase-3, Bax, IL-1β and TNF-α genes, and a remarkable increase in expression levels of Bcl-2, 3β-HSD and 17β-HSD3 genes compared with the I/R group. Administration of minocycline could also reduce the rate of germ cell apoptosis (TUNEL staining). Hence, minocycline was useful in the management of testicular torsion/detorsion.  相似文献   
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