Expression of aquaporin-7 and aquaporin-9 in tanycyte cells and choroid plexus during mouse estrus cycle.

Tanycytes are special ependymal cells located in the ventrolateral wall and floor of the third ventricle having processes extending nuclei that regulate reproductive functions and around of vessels in median eminance. The aquaporins (AQPs) are a family of transmembrane proteins that transport water and glycerol. AQP-7 and -9 are permeable to other small molecules as glycerol and therefore called aquaglyceroporins. In this study, we aimed to show localization of AQP-7 and -9 in epithelial cells of choroid plexus and tanycytes during female mouse estrus cycle. AQP-7 and -9 proteins were detected in α2 and ß1 tanycytes in prœstrus stage. Interestingly, there is no staining in estrus stage in any type of tanycytes. We observed weak immunoreactivity in α1, α2 and ß1 tanycyte cells in metestrus stage for AQP-7 and α1 for AQP-9 protein. AQP-7 and -9 showed intense immunoreactivity in α2, ß1 and ß2 tanycyte cells during diestrus stage. Consequently, AQP-7 and -9 showed differential staining pattern in different stages of mouse estrus cycle. In the light of our findings and other recent publications, we suggest that AQP-7 and -9-mediated glycerol transport in tanycyte cells might be under hormonal control to use glycerol as a potential energy substrate during mouse estrus cycle.

Effects of drag reducing polymer on atherosclerosis.

In order to determine the effect of drag reducing polymers on the occurrence of atherosclerosis, the Guinea pigs were used as the experimental animals. The inhibitory effect of a drag reducing polymer (polyacrylamide) on atherosclerosis in the aortas of Guinea pigs on a high cholesterol diet (2%) was investigated over a period of 6 months. The aortas, livers, kidneys and lungs of the animals, which were separated into four experimental groups (control, polymer, cholesterol and cholesterol + polymer) were also investigated both macroscopically and light microscopically. The selected physiological parameters such as, plasma cholesterol levels, plasma hemoglobin, hematocrit and total lipid values were determined at regular intervals for each group. The results indicate that the atherosclerosis in aorta of the animals receiving the polymer injection is suppressed significantly and the drag reducing water soluble polymers may be effectively applied against atherosclerosis.

A case of neurenteric cyst.

An eight-month-old female infant with a neurenteric cyst situated in the lumbar region is presented because of its rarity and because it can mimic other neurological malformations which occur on the same site. Microscopic examination of the surgically excised cyst revealed Water-Paccini corpuscles, lymphoid follicles, intestinal mucosa and meningeal tissue which originated from two ectoderm and endoderm-germ layers.

The effects of levothyroxine substitution on body composition and body mass after total thyroidectomy for benign nodular goiter.

OBJECTIVE: Many patients who have undergone total thyroidectomy complain about weight gain and changes in body composition. This prospective study was designed to evaluate the effect of thyroxine replacement on body mass index (BMI) and body composition following total thyroidectomy for benign multinodular goiter. METHODS: Thirty-three consecutive patients were enrolled. The patients of those histopathological examination revealed carcinoma (n=5) and who did not present for the 6th month follow-up visit (n=6) were excluded. Thyroxine (T4, 100 µg, dose range 50-200 µg) was started in all patients immediately after the surgery and adjusted according to plasma TSH and FT4-FT3 levels in the postoperative 3rd week and postoperative 3rd and 6th months respectively to achieve optimal TSH within normal reference range (0.5- 4.2 mU/L). Changes in weight, BMI and anthropometric measurements were performed preoperatively and in the postoperative 3rd and 6th months. RESULTS: The study completed with 22 patients (17 female and 5 male, mean: 45.8 years; range: 26-64 years). Fourteen patients maintained euthyroid status and eight had subclinical hypothyroidism. There were no significant differences between the subclinical hypothyroid and euthyroid patients in BMI and the other anthropometric values (p>0.05). In the comparisons for age, there were significant changes with regarding weight and BMI. Increases in weight were noted as 2.2±2.7 kg in age over 45 (n= 14, mean: 52.7 years, range: 46-64 years), while 0.1±1.3 kg in age under 45 years (mean; 33.8, range: 26-43 years) and BMI as 0.8±1.0 in age over 45 years compared to 0.04±0.5 in age under 45 years, respectively (p=0.025 and p=0.029, respectively). No significant differences were noted in other anthropometric parameters at the end of 6th month compared to the baseline value except the triceps skin fold (p=0.027). CONCLUSION: Levothyroxine replacement had no effect on their body composition; however, age was found to be an important factor for weight gain and change in BMI during the midterm follow-up period.

The cerebrovascular response to experimental lateral head acceleration.

A number of microvascular changes, such as the development of astrocyte lucency, increased endothelial pit/vesicle activity, development of crater like lesions, and endothelial microvilli have been reported after injury to the brain. Lateral head acceleration in the non-human primate, however, still provides the best experimental model for human diffuse axonal injury. No attempt has yet been made to document the spatial extent or time course of the microvascular response to acceleration injury to the head. We have examined the brains of baboons 1, 4, 6, and 12 h and 7 days after acceleration injury to the head to analyse the microvascular response. In the experimental animals there was a short-term rise in intracranial pressure followed by a long-term resolution, and a reduction in both mean arterial blood pressure and cerebral perfusion pressure which, however, never dropped below 75% of baseline for more than 5 min after injury in any animal. We found evidence for extravasation of blood in a small number of blood vessels in all parts of the brain. Interendothelial tight junctions are not disrupted. Pit/vesicle activity rises in the 1st h in the occipital cortex, but not until 4 h in the frontal cortex, and remains elevated for at least 7 days. There is little change in the thalamus. Development of microvilli is most rapid in the frontal cortex with peak values at 1 h, but slower in the thalamus and occipital cortex where peak values are only obtained at 6 h. Highest numbers of microvilli occur in parasagittal regions of the brain.(ABSTRACT TRUNCATED AT 250 WORDS)