effects of testosterone on oxidative stress markers in mice with spinal cord injuries

Background: Spinal cord injury [SCI] causes infertility in male patients through erectile dys-function, ejaculatory dysfunction, semen and hormone abnormalities. Oxidative stress [OS] is involved in poor semen quality and subsequent infertility in males with SCI. The aim of this study is to examine the effects of SCI on the level of testosterone hormone

Materials and Methods: In this experimental study, we evaluated the effects of exogenous testosterone on the activity of the antioxidant enzymes superoxide dismutase [SOD] and glutathione peroxidase [GPx] as well as the levels of malondialdehyde [MDA] and protein carbonylation [PCO], as markers of OS, in 10 groups of SCI mice. Total antioxidant capacity [TAC] was determined using the 2,29-azinobis-[3-ethylbenzothiazoline-6-sulfonic acid] [ABTS] radical cation assay

Results: Exogenous testosterone administration in mice with SCI significantly reduced SOD and GPx enzyme activities and MDA level. There was no significant decrease in PCO content. In addition, TAC remarkably increased in the sham and SCI groups not treated with testosterone but remained unchanged in all other experimental groups. Exogenous testosterone also reduced serum testosterone levels in all groups except the positive control group

Conclusion: Our cumulative data indicated that SCI could cause sterility by disturbing the plasmatic testosterone balance. The normal level of endogenous testosterone was not completely restored by exogenous testosterone administration

effect of timing of decompression on neurologic recovery and histopathologic findings after spinal cord compression in a rat model

Prior animal models have shown that rats sustaining 3-second immediate spinal cord compression had significantly better functional recovery and smaller lesion volumes than rats subjected to compression times of 1 hour, 6 hours, 3 weeks, and 10 weeks after spinal cord injury. We compare locomotor rating scales and spinal cord histopathology after 3 seconds and 10 minute compression times. Ten rats were assigned into two early [3-second] and late [10-minute] compressive surgery groups. Compressive injury was produced using an aneurysmal clip method. Rats were followed-up for 11 weeks, and behavioral assessment was done by inclined plane test and tail-flick reflex. At the end of the study, the rats were sacrificed, and spinal cord specimens were studied in light and EM. Basso, Beattie and Bresnahan [BBB] locomotor rating scales were significantly better in the early compression group after the 4th week of evaluation [P<0.05] and persisted throughout the remainder of the study. Histopathology demonstrated decreased normal tissue, more severe gliosis and cystic formation in the late group compared to the early group [P<0.05]. In EM study, injuries in the late group including injury to the myelin and axon were more severe than the early compression group, and there was more cytoplasmic edema in the late compression group. Spinal cord injury secondary to 3-second compression improves functional motor recovery, spares more functional tissue, and is associated with less intracellular edema, less myelin and axon damage and more myelin regeneration in rats compared to those with 10 minutes of compression. Inclined plane test and tail-flick reflex had no significant difference

[Study of the association between estrogen receptor alpha gene expression in the levels of RNA and protein in primary breast tumors]

Estrogen receptor alpha protein status is determined by routine immunohistochemistry analysis in all malignant breast tumors. This assay has its limitations. RNA based techniques are potential complements for immunohistochemistry but it must be noticed that gene silencing may occur at different levels from RNA to protein. The aim of this study was the comparison of the results from these two assays and characterizing the tumors subgroup in which gene expression occurs at RNA level but the target protein is absent. 92 primary breast tumors including their clinical and IHC results were collected before treatment. Estrogen receptor gene expression of tumors was studied by Reverse Transcription Polymerase Chain Reaction [RT PCR]. In this assay, GAPDH was used as a reference gene. 36.6% of tumors with negative estrogen receptor protein showed gene expression at mRNA level. In this subgroup most of the patient were older than 50 years and in stages 3 or 4 of breast cancer and had poor prognosis according to Nottingham prognostic index. Most cases of the perineural invasion have been seen in this subgroup. It seems that RT-PCR assay would enable us to recognize a subgroup of breast tumors with poor prognosis which expresses RNA but not protein

Detection of human papillomavirus in squamous cell carcinoma of conjunctiva by nested PCR: a case control study in Iran

Squamous-cell carcinoma [SCC] of the eye conjunctiva is a rare tumor. Its link with immune impairment suggests that infectious agents such as human papillomavirus [HPV] may be involved in the etiology of SCC. We conducted a case-control study on 50 SCC cases [mean age: 65.2] and 50 age frequency-matched control patients with lesion-free, normal conjunctival biopsies [mean age: 63.8] obtained from the cancer registry archive at Pathology Department of Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran, where SCC has become the most common conjunctival malignancy. MY/GP nested PCR was performed for HPV detection and E6/E7 consensus primers in combination of type specific primers were used in another nested PCR series for HPV typing. HPV DNA was detected in 46 of 50 samples of squamous cell carcinoma and none of the normal biopsies by nested PCR using primer sets of the HPV consensus L1 region [MY/GP]. Subsequently, specimens from the 46 positive cases were subjected to specific PCR. Although 630bp amplicon was produced in 44 of 46 samples [E6/E7 primers], none of the specific HPV PCR reactions for HPV DNA type 16, 18, 31 or 33 resulted in the detection of HPV DNA in the 44 SCC specimens of the conjunctiva. Current results confirm the role of HPV in the etiology of conjunctival SCC. The absence of HPV 16, 18, 31 and 33 in conjunctival SCC in this study raise doubts about the role of genital types of HPV in conjunctival carcinomas

Comparison between transepicardial cell transplantations: Autologus undifferentiated versus differentiated marrow mesenchymal stem cells

Marrow-derived mesenchymal stem cells [MSCs] have been heralded as a source of great promise for the regeneration of the infarcted heart. There are no clear data as to whether or not in vitro differentiation of MSCs into major myocardial cells can increase the beneficial effects of MSCs. The aim of this study was to address this issue. To induce MSCs to transdifferentiate into cardiomyocytes and endothelial cells, 5-Azacytidine and vascular endothelial growth factor [VEGF] were used, respectively. Myocardial infarction in rabbits was generated by ligating the left anterior descending coronary artery. The animals were divided into three experimental groups: I] control group, II] undifferentiated mesenchymal stem cell transplantation group, and III] differentiated mesenchymal stem cell transplantation group. The three groups received peri-infarct injections of culture media, autologous undifferentiated MSCs, and autologous differentiated MSCs, respectively. Echocardiography and pathology were performed in order to search for improvement in the cardiac function and reduction in the infarct size. Improvements in the left ventricular function and reductions in the infarcted area were observed in both cell transplanted groups [Groups II and III] to the same degree. There is no need for prior differentiation induction of marrow-derived MSCs before transplantation, and peri-infarct implantation of MSCs can effectively reduce the size of the infarct and improve the cardiac function