A rat model for studying effects of sacral neuromodulation on the contractile activity of a chronically inflamed bladder

OBJECTIVE: To develop an animal model in which the effects of electrical stimulation of the sacral nerves (sacral neuromodulation) on a chronic hyperactive urinary bladder can be studied. MATERIALS AND METHODS: In female rats the urinary bladder was instilled with mustard oil (0.4%); after 10 days the animals were anaesthetized with intraperitoneal urethane, the bladder catheterized and connected to a pressure transducer. Stimulating electrodes were placed into the sacral foramina bilaterally. The intensity and duration of sacral electrical stimulation was varied systematically to determine the effects of the sacral neuromodulation on bladder contractions. RESULTS: The main effect of the neuromodulation was an increase in the interval between contractions, i.e. during and for some time after the stimulation the contractions were completely abolished. The duration of the pause increased with the intensity and duration of stimulation. After the contractions had reappeared the frequency of contractions was reduced for a long period. In animals with chronic cystitis the effects of neuromodulation tended to be stronger (the pauses were longer) than in control animals with an intact bladder, but only in one test (increase of pause length with stimulus duration) was the difference statistically significant. CONCLUSIONS: The results show that this animal model is suitable for studying the effects and mechanisms of sacral neuromodulation on a chronic hyperactive urinary bladder.     

Mechanism of antiulcer effect of Neem (Azadirachta indica) leaf extract: effect on H<Superscript>+</Superscript>-K<Superscript>+</Superscript>-ATPase,oxidative damage and apoptosis

The mechanism of the antiulcer effect of Neem leaf aqueous extract to block gastric lesions in rat has been studied with emphasis on acid secretion, oxidative damage and apoptosis. The extract dose-dependently inhibits gastric lesions induced by restraint–cold stress, indomethacin and ethanol. In stress ulcer model, it is more effective than ranitidine but less effective than omeprazole. It also dose-dependently blocks pylorus ligation and mercaptomethylimidazole-induced acid secretion. In the pylorus-ligation model, it is less effective than omeprazole but as effective as ranitidine. It inhibits H⁺-K⁺-ATPase activity in vitro in concentration-dependent manner to inhibit acid secretion. Oxidative membrane damage by hydroxyl radical (^•OH) as measured by lipid peroxidation in stress ulcer is significantly blocked by leaf extract. Stress-induced apoptotic DNA fragmentation is also protected. The extract also prevents ^•OH-mediated mucosal DNA damage in vitro by scavenging the ^•OH. Neem leaf extract, thus, offers antiulcer activity by blocking acid secretion through inhibition of H⁺-K⁺-ATPase and by preventing oxidative damage and apoptosis.     

Fistula of submandibular gland-a rare presentation

Salivary fistulas commonly affect parotid gland. Sabmandibular fistulas are very rare. Most of them are congenital in origin and may be associated with abnormalities of the branchial apparatus. Traumatic submandibular fistulas on the other hand are very rare entities with only few cases reported till date.     

Managing severe lower limb spasticity in multiple sclerosis: does intrathecal phenol have a role?

OBJECTIVE: Established treatment options for managing severe lower limb spasticity and associated pain are of limited value in people with advanced multiple sclerosis (MS). This has resulted in a resurgence of the use of lumbar intrathecal phenol injection (IP). The aim of this study was to investigate the authors' experience with IP. METHODS: This observational study collected cross sectional data from patients with progressive MS who received IP for severe lower limb spasticity. Data from 25 patients were collected prospectively before and after treatment. In 15 cases the data related to the first treatment and in 10 to serial injections. Outcome measures collected included the Ashworth scale, a spasm frequency scale, a pain rating score, and the percentage achievement of practical goals. RESULTS: After injection, all patients demonstrated reduced lower limb tone bilaterally. After the initial injection there was significant improvement on the targeted as compared with the non-targeted side (Wilcoxon rank p=0.003), while no difference in the degree of improvement between the targeted and non-targeted side was seen after serial injections (Wilcoxon rank p=0.731). Twenty four patients were easier to position and 21 had a reduction in their spasm frequency and intensity. Eleven patients with pain reported benefit. Carers found washing and dressing easier in 16 patients and improved safety when using the hoist in 10. Six patients had recurrence of skin breakdown and five patients reported transient adverse changes in their bowel function. CONCLUSIONS: IP can reduce lower limb tone bilaterally after both initial and serial injections. This is most noticeable on the targeted side after initial injection. IP can reduce spasms and pain, leading to improvements in care and overall comfort. IP is an effective treatment option in the management of severe spasticity. Documented selection criteria are essential.     

Inhibition of ongoing responses in patients with traumatic brain injury

In addition to slowness of information processing, it is often assumed that executive functions are deficient in patients with traumatic brain injuries (TBI). The aim of this study was to investigate a specific executive function, the inhibition of ongoing responses in TBI. Twenty-seven patients with TBI and 27 orthopedic patients (OC) performed the stop signal task, which allows the estimation of the time it takes to inhibit an ongoing response. Contrary to expectations, patients with TBI did not perform worse than the OC in the inhibition of ongoing responses. Furthermore, subgroups of the TBI, with frontal and nonfrontal lesions, and with focal versus diffuse damage, did not show any differences in performance. None of the clinical, demographic or neuropsychological data had a significant relationship to inhibition time, apart from age, which showed a significant relationship only in the TBI. It seems likely that deficits in the inhibition of ongoing responses are not very common after TBI.     

A meta-analysis of the association between DRD4 polymorphism and novelty seeking

A meta-analytical review of 20 studies (n = 3907) of the association between DRD4 polymorphism and novelty seeking suggests the following conclusions: (a) on average, there is no association between DRD4 polymorphism and novelty seeking (average d = 0.06 with 95% CI of +/- 0.09), where 13 reports suggest that the presence of longer alleles is associated with higher novelty seeking scores and seven reports suggest the opposite; (b) there is a true heterogeneity among the studies (ie, unknown moderators do exist) but the strength of the association between DRD4 polymorphism and novelty seeking in the presence of any (unknown) moderator is likely to be weak; (c) search for moderators has not yielded any reliable explanation for the variability among studies. We propose that to find such moderators, theory-driven research for potential interaction, coupled with larger sample sizes should be employed. The growing availability of powerful statistical techniques, high-throughput genotyping and large numbers of polymorphic markers such as single nucleotide polymorphisms makes such proposed studies increasingly feasible.     

Failure of physiologic transformation of the spiral arteries in patients with preterm labor and intact membranes

OBJECTIVE: The purpose of this study was to determine whether abnormal placentation (defined as the failure of physiologic transformation of spiral arteries) is present in patients with preterm labor and intact membranes who delivered a preterm neonate. STUDY DESIGN: A cross-sectional study was conducted to examine the histopathologic findings in the placental bed and placenta of patients with preterm labor and intact membranes (n=27), preeclampsia (n=43), and healthy pregnant women at term (n=103). Immunohistochemistry studies with cytokeratin 7 and periodic acid-Schiff were used to detect trophoblast and fibrinoid, respectively, and diagnose the failure of physiologic transformation of the spiral arteries. RESULTS: The mean percentage of spiral arteries with failure of physiologic transformation in the myometrium was significantly higher in patients with preterm labor and preeclampsia than in normal pregnant women at term (P=.0004 and P<.0001, respectively). Similar findings were observed in the decidual segment of spiral arteries within the placental bed (P=.001 and P<.0001). In contrast, the mean percentage of the spiral arteries with failure of physiologic transformation in the decidua of the basal plate was not significantly different between patients with preterm labor and normal pregnant women (P=.17). CONCLUSION: Failure of physiologic transformation of the spiral arteries in the myometrial and decidual segments of the placental bed is frequent in patients with preterm labor and intact membranes.