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The protective effect of thymoquinone was investigated against cadmium‐induced testicular toxicity in rats. Testicular toxicity was induced by a single intraperitoneal (i.p.) injection of cadmium chloride (2 mg kg?1). Thymoquinone treatment (10 mg kg?1 day?1, i.p.) was applied for five consecutive days, starting 3 days before cadmium administration. Thymoquinone significantly attenuated the cadmium‐induced decreases in serum testosterone, and testicular reduced glutathione and superoxide dismutase activity and significantly decreased the elevations of testicular malondialdehyde, nitric oxide and cadmium ion levels resulted from cadmium chloride administration. Also, thymoquinone ameliorated the cadmium‐induced testicular tissue injury observed by histopathological examination. In addition, thymoquinone significantly decreased the cadmium‐induced expression of inducible nitric oxide synthase, tumour necrosis factor‐α, cyclooxygenase‐2, nuclear factor‐κB and caspase‐3 in testicular tissue. It was concluded that thymoquinone, through its antioxidant and anti‐inflammatory activities, may represent a potential candidate to protect the testes against the detrimental effect of cadmium exposure. 相似文献
4.
Molecular signalling of a novel curcumin derivative versus Tadalafil in erectile dysfunction 下载免费PDF全文
M. T. Abdel Aziz A. M. Rezq H. M. Atta H. Fouad A. M. Zaahkouk H. H. Ahmed D. Sabry H. M. Yehia 《Andrologia》2015,47(6):616-625
The efficacy of a novel curcumin derivative (NCD) versus tadalafil in erectile signalling was assessed. Ten control male rats and 50 diabetic male rats were used and divided into the following: diabetic (DM), curcumin (CURC), NCD, tadalafil and NCD combined with tadalafil rat groups. Cavernous tissue gene expression of heme oxygenase‐1 (HO‐1), Nrf2, NF‐B and p38, enzyme activities of heme oxygenase (HO) and nitric oxide synthase (NOS), cGMP and intracavernosal pressure (ICP)/mean arterial pressure (MAP) were assessed. Results showed that 12 weeks after induction of diabetes, erectile dysfunction (ED) was confirmed by the significant decrease in ICP/MAP, a significant decrease in cGMP, NOS, HO enzyme activities, a significant decrease in HO‐1 gene and a significant increase in NF‐?β, p38 genes. Administration of all therapeutic interventions led to a significant increase in ICP/MAP, cGMP levels, a significant increase in HO‐1 and NOS enzymes, a significant increase in HO‐1, and Nrf2 gene expression, and a significant decrease in NF‐?β, p38 gene expression. NCD or its combination with tadalafil showed significant superiority and more prolonged duration of action. In conclusion, a tendency was observed that CURC and NCD have high efficacy and more prolonged duration of action in enhancing erectile function. 相似文献
5.
The purpose of this study was to determine if Enterococcus spp. are more prevalent in endodontically treated teeth with periradicular lesions compared with teeth that require retreatment but have no periradicular rarefaction. Fifty-eight teeth that had received root canal therapy more than 1 yr previously and required retreatment were included. Designation of lesion versus no lesion was determined by two experienced endodontists. DNA extraction and PCR amplification were performed using ubiquitous 16S rDNA bacterial primers, as well as Enterococcus spp.-specific primers. The results showed that the overall prevalence of bacteria was 90% and Enterococcus spp. was 12%. chi analysis revealed a statistically significant relationship between the presence of a lesion and the presence of bacteria, as detected by the universal primers (p = 0.032). Using logistic regression, a statistically significant relationship was found between teeth with normal periapex and the presence of Enterococcus spp. (p = 0.023). This study revealed that bacteria are significantly associated with endodontic treatment failure but enterococci are not associated with disease. 相似文献
6.
Salama FS Schulte KM Iseman MF Reinhardt JW 《The journal of contemporary dental practice》2006,7(5):54-61
AIM: The aim of this study was to assess the effect of repeated (twice) applications of two fluoride varnishes (Duraflor and CavityShield) on the surface micromorphology of a high-viscosity glass ionomer (Fuji IX GP), a compomer (F2000), and a flowable composite (Filtek Flow) using a profilometer and scanning electron microscope (SEM). METHODS AND MATERIALS: Fifteen specimens were prepared from each material, surface roughness (Ra) was measured with a profilometer, and an impression was made for epoxy replicas. The fluoride varnishes were applied to the experimental specimens of each material at repeated intervals of 48 hours. For all specimens, Ra was measured and SEM replicas were examined. RESULTS: The final Ra of glass ionomer was 3.49 +/- 0.59 (mean +/- SD) for CavityShield, 4.69 +/- 1.33 for Duraflor, and 2.96 +/- 1.53 for the controls. The final Ra of flowable composite was 0.53 +/- 0.20 for CavityShield, 2.61 +/- 3.08 for Duraflor, and 0.15 +/- 0.09 for controls. For glass ionomer and flowable composite, Duraflor was associated with a significantly higher roughness at the final measurement compared to controls (P < 0.05). SEM micrographs showed differing surface topographies which in many specimens confirmed Ra analysis. CONCLUSION: Fuji IX GP and Filtek Flow showed significantly higher roughness after two applications of Duraflor compared to controls. 相似文献
7.
The effectiveness of endodontic antimicrobial treatment could be determined using sensitive molecular methods. The purpose of this study was to determine if antibiotics or endodontic reagents interfere with the ability of PCR to detect Enterococcus faecalis in vitro. Amoxicillin (25 mg/ml), clindamycin (15 mg/ml), tetracycline (25 mg/ml), doxycycline (10 mg/ml), calcium hydroxide, 1% buffered sodium hypochlorite (NaOCl1), 3% and 6% unbuffered NaOCl (NaOCl3 and NaOCl6), 2% chlorhexidine (CHX), 5% tincture iodine (TI), 2% iodine potassium iodide (IKI), chloroform (CF), 70% ethyl alcohol, 5% sodium thiosulphate, 5% citric acid or saline were added to 10 or 10 cells/ml E. faecalis ATCC 19433 for 1 h (1 wk for Ca(OH)2). Using PCR, all specimens were positive except for NaOCl3 and NaOCl6. PCR with Ca(OH)2 was positive with 10 cells/ml but negative with 10 cells/ml. The following reagents yielded negative culturing results: all antibiotics, Ca(OH)2, CHX, IKI, TI, NaOCl3, NaOCl6, and CF. BacLight nuclear staining revealed the presence of viable cells in all PCR positive, culture negative combinations, except for those with CF. Therefore, in the presence of threshold values of bacterial concentrations, all reagents tested except for NaOCl3 and NaOCl6 do not interfere with the detection of E. faecalis using PCR. 相似文献
8.
Fouad Ayoub Maria Saadeh Hasan Fayyad-Kazan Ramzi Haddad 《Journal of cranio-maxillo-facial surgery》2019,47(2):273-279
Introduction
The majority of previous research delineating the morphological characteristics of the orolabial region has been on Caucasian populations, with very minor research on Mediterranean populations, and none on the Lebanese population.Aim
The primary aim was to collect information on the gender-specific 3D morphology of the mouth and lips in young Middle Eastern adults. The secondary aim was to explore the presence of associations between orolabial morphology and age and body mass index (BMI), and to assess correlations between linear orolabial dimensions and area/volume measures.Methods
The study used non-invasive stereophotogrammetry to collect information on gender-specific 3D labial morphology (linear distances, areas, and volumes) for 122 adult Lebanese subjects, aged 18–30 years (47 males, 75 females). Associations between labial morphology and age and body mass index were assessed, in addition to correlations between linear orolabial dimensions and area/volume measures.Results
All linear, angular, area, and volume lip measurements displayed significant variability. Both lip area and volume were smaller in the upper than in the lower lip. Eighteen out of the 20 linear measurements were significantly larger in males. The ratio, area, and volume measurements mostly displayed no statistically significant gender dimorphism.Conclusions
Alongside presenting the first documented report on anthropometric labial measurements of a young Lebanese adult population, this research highlights the presence of gender dimorphism in linear and angular measurements, but not in area and volume measurements, and a strong association between certain linear labial measurements and lip area and volume. In addition, it presents pilot data on the association between labial anthropometry and body mass index. 相似文献9.
Mazen M. Jamil Al-Obaidi Fouad Hussain Al-Bayaty Rami Al Batran Pouya Hassandarvish Elham Rouhollahi 《Archives of oral biology》2014
Objective
This study has attempted to evaluate the effects of ellagic acid (EA) on alveolar bone healing after tooth extraction in rats.Design
Twenty-four Sprague Dawley (SD) male rats (200–250 g) were selected and were anaesthetised for the extraction of upper left incisor. Then, the rats were divided into two groups, comprising 12 rats each; the first group has been considered as a control group and was given only normal saline, whereas, the second group (treated group) was intragastrically administrated with EA daily once, for 28 days. Then three rats from each group had been selected on 7th, 14th, 21st, and 28th days to dissect their maxilla tissue either for histological observation and homogenisation purposes. The tissues fixed, decalcified and embedded in paraffin. Serial sections of 5 μm thickness were prepared and stained with haematoxylin and eosin (H&E) for the histological study. Similar sections were taken for immunohistochemical analysis to assess osteocalcin (OSC) and osteopontin (OPN). Furthermore, Malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in homogenated gingival maxilla tissue of rat by commercial kit.Results
Based on the histological analysis we have identified that, EA treatment has induced earlier trabecular bone deposition in the treated group, resulting in more organised bone matrix on the 14th, 21st, and 28th days after tooth extraction, as against the control group. In comparison to control group, the positive labelling of OSC and OPN of the treated group have been highly expressed in the alveolar socket on 14th, and 21st days, which has indicated a the possibility of formation of new bone trabeculae at the beginning of the mineralisation process, after tooth extraction. In the EA treatment group, lipid per-oxidation (MDA) was significantly decreased (P < 0.05), as opposed to the control group. However, the antioxidant defense enzyme (SOD) was significantly increased in the maxilla tissue treated with EA (P < 0.05), compared to control group, which suggests that, after tooth extraction, EA plays an important role in the protection against the induction of lipid per-oxidation, particularly after 28 days of treatment with EA.Conclusion
This study has concluded that, EA may accelerated the healing process in teeth socket of rats. Furthermore, the EA treated group showed a stronger positive immunolabelling for OSC and OPN, when compared with the control group. 相似文献10.
Trauma is the leading cause of mortality in children over one year of age in industrialized countries. In this retrospective study we reviewed all chest trauma in pediatric patients admitted to Mansoura University Emergency Hospital from January 1997 to January 2007. Our hospital received 472 patients under the age of 18. Male patients were 374 with a mean age of 9.2±4.9 years. Causes were penetrating (2.1%) and blunt trauma (97.9%). The trauma was pedestrian injuries (38.3%), motor vehicle (28.1%), motorcycle crash (19.9%), falling from height (6.7%), animal trauma (2.9%), and sports injury (1.2%). Type of injury was pulmonary contusions (27.1%) and lacerations (6.9%), rib fractures (23.9%) and flail chest (2.5%), hemothorax (18%), hemopneumothorax (11.8%), pneumothorax (23.7%), surgical emphysema (6.1%), tracheobronchial injury (5.3%), and diaphragm injury (2.1%). Associated lesions were head injuries (38.9%), bone fractures (33.5%), and abdominal injuries (16.7%). Management was conservative (29.9%), tube thoracostomy (58.1%), and thoracotomy (12.1%). Mortality rate was (7.2%) and multiple trauma was the main cause of death (82.3%) (P<.001). We concluded that blunt trauma is the most common cause of pediatric chest trauma and often due to pedestrian injuries. Rib fractures and pulmonary contusions are the most frequent injuries. Delay in diagnosis and multiple trauma are associated with high incidence of mortality. 相似文献