Divergent expression and localization of aquaporin 5, an exocrine-type water channel,in the submandibular gland of Sprague-Dawley rats

By Western blot analysis, the expression level of aquaporin (AQP) 5 in the submandibular gland (SMG) was found to be different among individual rats of the Sprague-Dawley (SD) strain. Such differences were observed for AQP5 but not for AQP1 and consequently the SD strain was divided into two groups, one expressing a high level of AQP5 and the other a low one. The difference in average intensity of expression between the two groups was more than twofold. Immunohistochemical analysis of the SMG demonstrated that the AQP5 protein was localized in the basal and apical/lateral plasma membrane of acinar cells in rats expressing the high level of AQP5. In the rat expressing the low level, however, this channel protein was localized strongly in the apical/lateral plasma membrane, but only very weakly in the basal membrane of the acinar cells. Such a diverse localization of AQP5 was confirmed by Western blotting as well. Breeding between brother and sister was repeated for two times within high expressers and low expressers to obtain the third generation progenies (F2); the AQP5 level of the SMG in the third generation (F2 rats) from high expressers was significantly higher than the F2 from low expressers. Our present study suggests the existence of genetic variation in the expression of a water channel protein, AQP5, in rats.     

Minimal progesterone support required for the maintenance of pregnancy in mice

A study of the degree of progesterone support required for the maintenance of various stages of pregnancy was undertaken in mice. Mated females were ovariectomized at various stages of pregnancy and progesterone and oestradiol support provided by s.c. Silastic implants with known release characteristics. In the earliest stages of pregnancy (days 1-5), very low concentrations of progesterone (<25% of normal physiological values) were sufficient to maintain pre-implantation stages and allow implantation. In the immediate post-implantation period (days 5-9), the development of implantation sites and decidualization required considerably higher progesterone support. In mid-pregnancy (days 11-14), progesterone alone could not maintain pregnancy unless present in very high amounts; however, the presence of oestradiol during this period lowered the progesterone requirements to well within the physiological range. This effect of oestradiol started on day 11 but required the level of oestradiol support to be kept within strictly defined limits, with high concentrations inducing abortion. Progesterone alone was able to maintain pregnancy from day 15. These results indicate that the minimal progesterone support required for pregnancy in mice varies considerably at different stages of pregnancy and is at least partly modulated by oestradiol.      

Elastin point mutations cause an obstructive vascular disease, supravalvular aortic stenosis

Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular disease that affects the aorta, carotid, coronary and pulmonary arteries. Previous molecular genetic data have led to the hypothesis that SVAS results from mutations in the elastin gene, ELN. In these studies, the disease phenotype was linked to gross DNA rearrangements (35 and 85 kb deletions and a translocation) in three SVAS families. However, gross rearrangements of ELN have not been identified in most cases of autosomal dominant SVAS. To define the spectrum of ELN mutations responsible for this disorder, we refined the genomic structure of human ELN and used this information in mutational analyses. ELN point mutations co-segregate with the disease in four familial cases and are associated with SVAS in three sporadic cases. Two of the mutations are nonsense, one is a single base pair deletion and four are splice site mutations. In one sporadic case, the mutation arose de novo. These data demonstrate that point mutations of ELN cause autosomal dominant SVAS.      

Contextual modulation of synchronization to random dots in the cat visual cortex

Synchronization of neuronal activity has been proposed as a binding mechanism for integration of image properties into one coherent percept. In the present study, we investigated the contextual modulation of synchronization to random dot patterns. Coherent motion of random dots evoked well synchronized responses in area 17 of anaesthetized cats when the stimulus was presented in the compound receptive field of recorded sites. Gradually changing the directional coherence of random dots in the surround while maintaining fully coherent motion of the stimulus in the receptive field significantly suppressed synchronization of neuronal activity for some stimulus conditions. However, usually one or two peaks of increased synchronization were found in the surround coherence tuning curves with low (8–12%) and/or moderate (25–50%) coherence in the surround. At the population level, synchronization was significantly depressed with incoherent motion in the receptive field and when both the surround and the receptive field were jointly stimulated with 0% coherence. The intriguing finding was the discovery of two distinct groups of cells with opposite synchronization changes dependent on the presence or absence of significant synchronization in their spontaneous activity. The latter group of neurons showed peaks of increased synchronization with lower surround coherence, thus probably being more sensitive to the direction of the surround motion. Overall, our findings support the notion that binding of stimulus properties can be achieved by synchronized activity of cortical cells. However, our findings go further than the original hypothesis of feature binding by synchrony to show that synchronization of cortical activity may be directly related to the decision making processes, which in turn are related to the threshold of perception of coherent motion.     

A randomized trial of ceftriaxone versus trimethoprim-sulfamethoxazole to prevent ventriculoperitoneal shunt infection.

BACKGROUND AND PURPOSE: Shunt infection represents a particularly morbid condition, which can also result in mortality. In order to decrease the high morbidity and mortality rates, prevention is an essential step. The purpose of this study was to compare the prophylactic use of ceftriaxone and trimethoprim-sulfamethoxazole (SXT) for the prevention of ventriculoperitoneal (VP) shunt infection. METHODS: In this prospective, single-institution, randomized clinical trial, 107 children with hydrocephalus and an indication for shunting were randomly assigned to prophylaxis with ceftriaxone (n = 50) or SXT (55), each administered as a single dose during anesthesia and two divided doses postoperatively. Patients were followed up for at least one year. RESULTS: The mean age of patients was 15 months, and 85% were aged 6 months or younger. During the first postoperative year, meningitis occurred in 13.5% of patients receiving ceftriaxone and 14.5% of the SXT group, with no statistically significant difference between the groups. Younger age, presence of cerebrospinal fluid leakage and aqueductal stenosis as a cause of hydrocephalus showed significant correlation with meningitis occurrence on univariate analysis. However, only the latter 2 factors were associated with meningitis on multivariate analysis. The risk of shunt infection did not correlate with the gender of the patient, time of VP shunt surgery, or duration of hospitalization for shunting. CONCLUSION: Ceftriaxone and SXT showed similar efficacy in preventing shunt infection. Cerebrospinal fluid leakage before or after VP shunt placement and aqueductal stenosis were independent risk factors for meningitis after VP shunt.     

Anxiety during pregnancy and fetal attachment after in-vitro fertilization conception

The aim of this study was to compare 70 couples who had conceived by in- vitro fertilization (IVF) with 63 matched controls for the prevalence of anxiety and quality of attachment to the baby during pregnancy. Results for mothers showed no group differences using a global measure of anxiety, the Spielberger State-Trait Anxiety Inventory. However, pregnancy-specific measures revealed significantly higher levels of anxiety in IVF mothers about the survival and normality of their unborn babies, about damage to their babies during childbirth and about separating from their babies after birth. When IVF mothers were differentiated according to the number of treatment cycles, more differences in anxiety level were revealed, with most increases occurring in mothers who had experienced two or more treatment cycles. IVF fathers did not differ from controls on the global anxiety measure. No data on pregnancy-specific anxiety were available for fathers. Neither IVF mothers nor IVF fathers differed from controls on measures of attachment to the baby during pregnancy. Results are discussed in the context of the need for researchers to employ differentiated and issue-specific measures to identify concerns that may be unique to IVF couples. Clinical implications regarding the need for psychological support during pregnancy are also discussed.      

Efficacy of allogeneic cord blood platelet gel on wounds of dystrophic epidermolysis bullosa patients after pseudosyndactyly surgery

Epidermolysis bullosa (EB) is a rare genetic disorder characterized by the formation of blisters and wounds in skin and mucous membranes; it is classified into four types and has various methods of treatment. Management of previous wounds and prevention of formation of new lesions are the most important strategies in the course of therapy to improve patient's quality of life; lack of wound management can lead to further complications such as infection. The current study investigated the therapeutic effects of allogeneic platelet gel (prepared from umbilical cord blood) in a group of children diagnosed with dystrophic epidermolysis bullosa (DEB) eligible for surgical correction of pseudosyndactyly in the hand. The post‐surgical clinical outcome in this group was compared with the clinical outcomes of DEB patients receiving the standard treatment (paraffin gauze wound dressing and topical antibiotics) after corrective surgery. The current study results showed an increase in the rate of recovery and promotion of tissue granulation, complete wound healing, and a decrease in pain level and treatment period. The application of cord blood platelet gel topical dressing was not a conventional method of treatment in patients with DEB wounds and blisters. However, the current study results demonstrated that this gel dressing could effectively accelerate epithelialization and healing of the wounds and decrease patients' pain and post‐surgical recovery period, which altogether leads to improvements in patients' overall quality of life.