Elevated NMDA receptors in parkinsonian striatum.

Dopamine-glutamate interactions contribute to normal striatal function and have been implicated in neurotoxicity at nigrostriatal dopamine (DA) terminals. The present study examined the striata of idiopathic Parkinson's disease (PD) patients and age-matched controls for regional differences in the DA transporter and binding to N-methyl-D-aspartate (NMDA) receptors. [3H]Mazindol labeling of the DA transporter was reduced by 70-80% in the caudate and putamen of PD patients, with reductions being more extensive dorsally than ventrally. In contrast, L-[3H]glutamate binding to NDMA-sensitive receptors was 20-40% higher in PD cases than in controls. These findings raise the possibility that modifications occur within corticostriatal glutamate synapses of PD patients, possibly as a consequence of reduced nigrostriatal DA activity.     

The stimulating effect of ganglioside injections on the recovery of choline acetyltransferase and acetylcholinesterase activities in the hippocampus of the rat after septal lesions

The effect of intramuscular administration of a mixture of gangliosides (21% GM₁, 39.7% GD_1a,, 16% GD_1b, 19% GT₁ in a daily dose of 50 mg per kg upon the time course of changes in hippocampal acetylcholinesterase and choline acetyltransferase activities after extensive medioventral septal lesions in the rat was checked on days 3, 5, 18 and 50 after the operation. Following the early decrease in the enzyme activities to about 25% of control due to degeneration, a gradual recovery up to about 50% of control activity at the 50th day was found. When gangliosides were administered, the recovery in the activity of both enzymes was more pronounced. The ratio of the enzyme activities from the animals injected with gangliosides to that from uninjected animals was 1.45 and 1.48 on the 18th day and 1.62 and 1.50 on the 50th day after the operation, for choline acetyltransferase and acetylcholinesterase activity, respectively. Since no significant effect of ganglioside injection was seen at early postoperative times i.e. on days 3 and 5, the effects seen on days 18 and 50 seem to be specifically due to facilitation of the recovery processes and not to retardation of the degeneration processes.Assuming that the spontaneous recovery of cholinergic enzyme activity reflects reinnervation of the hippocampus through collateral sprouting, gangliosides would seem to facilitate the regrowth of new cholinergic nerve terminals.     

Poor efficacy of ranitidine bismuth citrate-based triple therapies for Helicobacter pylori eradication.

BACKGROUND: Helicobacter pylori eradication rates have tended to decrease recently possibly related with increasing antibiotic resistance. The present study investigated the efficacy of three different ranitidine bismuth citrate (RBC) based triple regimens in a population with high prevalence of H. pylori. METHODS: 300 consecutive H. pylori positive patients with non-ulcer dyspepsia were randomized into three regimens: (1) RBC 400 mg, amoxicillin 1000 mg and tetracycline 500 mg [RBC-AT], (2) RBC 400 mg, amoxicillin 1000 mg and clarithromycin 500 mg [RBC-AC], (3) RBC 400 mg, metronidazole 500 mg and tetracycline 500 mg [RBC-MT]. Tetracycline was given q.i.d, all other drugs were given b.i.d. for 14 days. Gastroscopy and (14)C-Urea breath test (UBT) were performed before enrollment and UBT only was repeated 6 weeks after the end of treatment. RESULTS: 274 patients completed the protocols. The overall 'intention to treat' and 'per protocol' H. pylori eradication rates in all subjects were 57.6% (95% CI: 52-63) and 63.1% (95% CI: 57-68), respectively. The eradication rates achieved in the groups (RBC-AT, RBC-AC and RBC-MT) were 64.4% (95% CI: 54-74), 66.2% (95% CI: 56-76), and 58.9% (95% CI: 49-68) on 'per protocol' analyses, respectively. There was no difference in eradication rates, compliance and major side effects between the groups. CONCLUSION: The current RBC-based H. pylori eradication therapy is not adequately effective.     

Response to vaccination against hepatitis B in patients with Behcet's disease

BACKGROUND AND AIM: Hepatitis B virus infection is an important public health problem in Turkey. Although hepatitis B vaccination is regarded as safe and effective for the general population, recommendations for hepatitis B immunization in patients with Behcet's disease are not clear. The aim of the present study was to elucidate the response of patients with Behcet's disease to hepatitis B vaccination and to determine whether hepatitis B vaccination has any adverse effects on the course of the disease. METHODS: Thirteen patients with Behcet's disease and 15 healthy individuals were enrolled into a prospective study. All subjects received the 3-dose series of routine hepatitis B vaccine. Anti-hepatitis B surface response was evaluated 1-3 months after the third dose of vaccine. RESULTS: The responder rates for patient and control groups were 12/13 (92.8%) and 14/15 (93.8%), respectively. Statistical analysis showed no significant difference between the two groups in terms of both the responder rates and mean antibody titers. CONCLUSIONS: These preliminary findings might suggest that the majority of patients with Behcet's disease develop protective antibody response after hepatitis B vaccination and that the immune response against hepatitis B surface antigen is adequate, efficient and intact.     

Does moxifloxacin alter oxidant status in the cornea? An experimental study

Objective: In this experimental study, we investigated the possible effects of intracameral moxifloxacin on oxidative stress parameters and endothelial cell morphology in corneal tissue.

Methods: In total, 30 rats were randomly assigned to three groups of 10 rats: the sham group (Group 1, n?=?10); the control group (Group 2), where balanced salt solution (BSS) was administered at a dose of 0.01?cc (n?=?10); and the treatment group (Group 3), where moxifloxacin was administered at a dose of 0.05?mg/0.01?cc (n?=?10). Total antioxidant status (TAS) and total oxidant status (TOS) in corneal tissue and blood samples were measured and the oxidative stress index (OSI) was calculated. Also, corneal tissue histopathology was evaluated with caspase-3 and caspase-8 staining. Apoptotic activity was also evaluated.

Results: In blood samples, TAS, TOS, and OSI levels were not statistically significantly different (all p?>?0.05). Compared with the sham and control groups, TOS and OSI levels in cornea tissue were significantly different in the moxifloxacin group (all p?p?>?0.05). Compared with the sham and control groups, apoptotic activity was higher in the moxifloxacin group, in both immunohistochemical staining for caspase-3 and caspase-8.

Conclusions: Intracameral moxifloxacin injection seems to be safe systemically, but it may have toxic effects on corneal tissues, as suggested by oxidative stress parameters and a histopathological evaluation.     

Liver steatosis assessment: Correlations among pathology,radiology, clinical data and automated image analysis software

Quantitating hepatic steatosis is important in many liver diseases and liver transplantation. Since steatosis estimation by pathologists has inherent intra- and inter-observer variability, we compared and contrasted computerized techniques with magnetic resonance imaging measurements, pathologist visual scoring, and clinical parameters. Computerized methods applied to whole slide images included a commercial positive pixel count algorithm and a custom algorithm programmed at our institution. For all liver samples (n = 59), including pediatric, adult, frozen section, and permanent specimens, statistically significant correlations were observed between pathology, radiology, and each image analysis modality (r = 0.75–0.97, p < 0.0001), with the strongest correlations in the pediatric cohort. Statistically significant relationships were observed between each method and with body mass index (r = 0.37–0.56, p from <0.0001 to <0.05) and with albumin (r = 0.55–0.64, p < 0.05) but not with alanine aminotransferase or aspartate aminotransferase. Although pathologist assessments correlated (r = 0.64–0.86, 0.92–0.97, and 0.78–0.91 for microvesicular, macrovesicular, and overall steatosis, respectively), the absolute values of hepatic steatosis visual assessment were susceptible to intra- and inter-observer variability, particularly for microvesicular steatosis. Image analysis, pathologist assessments, radiology measurements, and several clinical parameters all showed correlations in this study, providing evidence for the utility of each method in different clinical and research settings.