Mediastinal anatomical landmarks, their variants and tips for video-assisted thoracoscopic navigation during oesophageal extirpation.

PURPOSE: There is no systematic description of primary anatomical landmarks that allow a surgeon to reliably and safely navigate the superior and posterior mediastinum's fat tissue spaces near large vessels and nerves during video-assisted endothoracoscopic interventions in the prone position of a patient. Our aim was to develop an algorithm of sequential visual navigation during thoracoscopic extirpation of the esophagus and determine the most permanent topographic and anatomical landmarks allowing safe thoracoscopic dissection of the esophagus in the prone position. METHODS: The anatomical study of the mediastinal structural features was carried out on 30 human cadavers before and after opening the right pleural cavity. RESULTS: For thoracoscopic extirpation of the esophagus in the prone position, anatomical landmarks are defined, their variants are assessed, and an algorithm for their selection is developed, allowing their direct visualization before and after opening the mediastinal pleura. CONCLUSION: The proposed algorithm for topographic and anatomical navigation based on the key anatomical landmarks in the posterior mediastinum provides safe performance of the video-assisted thoracoscopic extirpation of the esophagus in the prone position.

Effect of melatonin supplementation on pregnancy outcome in Wistar-Kyoto and Sprague-Dawley rats.

Although melatonin supplementation is known to influence numerous physiological functions, little is however known of its effects on pregnancy outcome. This study investigated the effects of melatonin supplementation on pregnancy outcome in Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats aged 12-13 weeks. Upon confirmation of proestrus, each female rat was housed overnight with a male of the same strain. On the next morning, following confirmation of mating (vaginal smear), WKY female rats were isolated into individual metabolic cages and given 0, 25, 50 or 100 mg/kg per day of melatonin in drinking water from day 1 of pregnancy to day 21 postpartum. SD females were given 0 or 100 mg/kg per day of melatonin. Maternal weight, duration of pregnancy, litter size, birth weight and body weight of pups up to day 42, and pup mortality were recorded. Data were analyzed using ANOVA for repeated measures. Compared to controls, maternal weight gain during pregnancy was significantly lower in melatonin-supplemented dams (P < 0.01). Litter size was significantly smaller in melatonin-supplemented dams (P < 0.01). Mean birth weight of pups was significantly lower only in pups of dams given 100 mg/kg per day of melatonin (P < 0.001). Mean body weight of pups of dams given melatonin was significantly lower than controls (P < 0.01). Pup mortalities were 9.5% and 21.6% in WKY dams given 25 and 100 mg/kg per day of melatonin respectively, and all pup deaths occurred after day 21 of weaning. The results suggest that melatonin supplementation during antenatal and postpartum period appears to adversely affect litter size, pup growth and mortality in WKY and SD rats. The precise mechanism causing the death is not clear.

Gastroprotective effect of Berberis vulgaris on ethanol-induced gastric mucosal injury: Histopathological evaluations.

OBJECTIVE: Modern treatment of peptic ulcers includes antibacterial and gastroprotective medications. However, current anti-ulcer drugs possess severe side effects. Therefore, all attempts to find new effective medications free from side effects are justified. Though Berberis vulgaris is a medicinal plant commonly used for the treatment of numerous disorders, gastroprotective effect of its leaf extract was not investigated before. MATERIALS AND METHODS: Gastric ulcer was modelled in Sprague-Dawley rats after treatment with B. vulgaris leaf extract containing 0.07% of alkaloids, 0.48% of flavonoids and 8.05% of tanning substances, 10 or 50 mg of dry extract/kg, changes in the stomach mucosa were assessed semi-quantitatively, and the gastric wall was evaluated for prostaglandin E2 level using ELISA and assessed histologically by calculation of the lesion index. RESULTS: B. vulgaris leaf extract at the dose of 50 mg/kg reduced the macroscopic ulcer score and the microscopic lesion index, increased prostaglandin E2 concentration in the gastric wall significantly higher than atropine and B. vulgaris leaf extract 10 mg/kg. CONCLUSION: The gastroprotective effect of the high dose of B. vulgaris leaf extract may be due to stimulation of prostaglandin E2 secretion in the stomach, and anti-oxidative and anti-inflammatory properties of polyphenolic complex of flavonoids and tannins present in the leaves of this plant.

Melatonin ameliorates the adverse effects of leptin on sperm.

This study examined the effects of melatonin on leptin-induced changes in sperm parameters in adult rats. Five groups of Sprague-Dawley rats were treated with either leptin or leptin and melatonin or melatonin for 6 weeks. Leptin was given daily via the intraperitoneal route (60 µg kg-1 body weight) and melatonin was given in drinking water (10 mg kg-1 or 20 mg kg-1 body weight per day). Upon completion, sperm count, sperm morphology, 8-hydroxy-2-deoxyguanosine, Comet assay, TUNEL assay, gene expression profiles of antioxidant enzymes, respiratory chain reaction enzymes, DNA damage, and apoptosis genes were estimated. Data were analyzed using ANOVA. Sperm count was significantly lower whereas the fraction of sperm with abnormal morphology, the level of 8-hydroxy-2-deoxyguanosine, and sperm DNA fragmentation were significantly higher in rats treated with leptin only. Microarray analysis revealed significant upregulation of apoptosis-inducing factor, histone acetyl transferase, respiratory chain reaction enzyme, cell necrosis and DNA repair genes, and downregulation of antioxidant enzyme genes in leptin-treated rats. Real-time polymerase chain reaction showed significant decreases in glutathione peroxidase 1 expression with increases in the expression of apoptosis-inducing factor and histone acetyl transferase in leptin-treated rats. There was no change in the gene expression of caspase-3 (CASP-3). In conclusion, the adverse effects of leptin on sperm can be prevented by concurrent melatonin administration.