Surface plasmon excitation on a grating assisted by a cholesteric liquid crystal layer.

While surface plasmon excitation assisted by nematic liquid crystal layers has been comprehensively studied in different aspects, application of cholesteric structures for surface plasmon excitation remains an unexplored area. Moreover, structures including cholesteric layers and metal grating for surface plasmon excitation have never been considered, to the best of our knowledge. We studied theoretically and experimentally such structures focusing on different regimes of propagation of normal modes in the cholesteric liquid crystal layer. The application of such structures for sensing is accordingly discussed.

Stability of diazepam in blood samples at different storage conditions and in the presence of alcohol.

Diazepam is one of the mostly used benzodiazepines and it is frequently analyzed in different biological samples, especially blood samples. The diazepam stability in the sample matrices is an important factor regarding reliable data obtaining. The storage is the main factor determining the stability of diazepam in blood samples and it is the object of the study presented. Remaining diazepam amount in spiked whole blood and plasma samples were tested at different storage temperatures, in the absence or presence of sodium fluoride as stabilizer as well as the influence of ethanol on diazepam stability was evaluated. The results of the study indicated that the temperature is the main storage factor affecting diazepam stability. In the fluoride stabilized blood samples the amount of diazepam decreases up to 85% of initial level when stored at -20° C for the period of testing (12 weeks). The presence of low (0.5 g/L) or high (3g/L) ethanol concentrations influences the stability of diazepam at -20 °C. In whole blood samples, the combination of sodium fluoride and ethanol decreases additionally (15-25%) the concentration of the analyte. Freeze-thaw experiments of whole blood samples show about 5-9% decrease in diazepam concentration after the first cycle. The freeze-thaw experiments on plasma samples, containing ethanol and/or fluoride show insignificant decreases of analyte concentration. Further experiments on benzodiazepines stability at different storage conditions or in combination of different factors should be undertaken in forensic toxicology to ensure the data quality, their reliability and reproducibility.

Qualitative visual image analysis of bruise age determination: a survey.

The evaluation of bruise color imaging is a very important task in forensic medicine. However, there is no standardized methodology in carrying out this task. In this paper, an attempt was made to review the different papers published in the literature on the visual assessment of bruise age determination, and derive color charts of daily bruise aging. Based on the color charts derived, the following observations can be made: (i) the bruise is red for day 1, (ii) there is no dominant color for day 2, whereas for day 3, blue is becoming slightly dominant, (iii) green is becoming dominant for days 4-6, with yellow color emerging, (iv) for day 7, there is coexistence of green and yellow, (v) yellow is highly dominant for days 7 to 14, with brown emerging. These charts can serve as guidelines for the qualitative evaluation of bruise imaging by visual analysis. Clearly, the need exists for the quantitative analysis of bruise color imaging.

Translating A2A antagonist KW6002 from animal models to parkinsonian patients.

Improving the translation of novel findings from basic laboratory research to better therapies for neurologic disease constitutes a major challenge for the neurosciences. This brief review of aspects of the development of an adenosine A2A antagonist for use in the management of Parkinson's disease (PD) illustrates approaches to some of the relevant issues. Adenosine A2A receptors, highly expressed on striatal medium spiny neurons, signal via kinases whose aberrant activation has been linked to the appearance of parkinsonian signs after dopaminergic denervation and to the motor response complications produced by dopaminomimetic therapy. To assess the ability of A2A receptor blockade to normalize certain of these kinases and thus benefit motor dysfunction, the palliative and prophylactic effects of the selective antagonist KW6002 were first evaluated in rodent and primate models. In hemiparkinsonian rats, KW6002 reversed the intermittent L-dopa treatment-induced, protein kinase A-mediated hyperphosphorylation of striatal alpha-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid receptor GluR1 S845 residues and the concomitant shortening in motor response duration. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned monkeys, coadministration of KW6002 with daily apomorphine injections acted prophylactically to prevent dyskinesia onset. These and related preclinical observations guided the design of a limited, randomized, controlled, proof-of-concept study of the A2A antagonist in patients with moderately advanced PD. Although KW6002 alone or in combination with a steady-state IV infusion of optimal-dose L-dopa had no effect on parkinsonian severity, the drug potentiated the antiparkinsonian response to low-dose L-dopa with fewer dyskinesias than produced by optimal-dose L-dopa alone. KW6002 also safely prolonged the efficacy half-time of L-dopa. The results suggest that drugs capable of selectively blocking adenosine A2A receptors could confer therapeutic benefit to L-dopa-treated parkinsonian patients and warrant further evaluation in phase II studies. They also illustrate a strategy for successfully bridging a novel approach to PD therapy from an evolving research concept to pivotal clinical trials.

Adenosine A(2A) receptor antagonist treatment of Parkinson's disease.

BACKGROUND: Observations in animal models suggest that A(2A) antagonists confer benefit by modulating dopaminergic effects on the striatal dysfunction associated with motor disability. This double-blind, placebo-controlled, proof-of-principle study evaluated the pathogenic contribution and therapeutic potential of adenosine A(2A) receptor-mediated mechanisms in Parkinson disease (PD) and levodopa-induced motor complications. METHODS: Fifteen patients with moderate to advanced PD consented to participate. All were randomized to either the selective A(2A) antagonist KW-6002 or matching placebo capsules in a 6-week dose-rising design (40 and 80 mg/day). Motor function was rated on the Unified PD Rating Scale. RESULTS: KW-6002 alone or in combination with a steady-state IV infusion of each patient's optimal levodopa dose had no effect on parkinsonian severity. At a low dose of levodopa, however, KW-6002 (80 mg) potentiated the antiparkinsonian response by 36% (p < 0.02), but with 45% less dyskinesia compared with that induced by optimal dose levodopa alone (p < 0.05). All cardinal parkinsonian signs improved, especially resting tremor. In addition, KW-6002 prolonged the efficacy half-time of levodopa by an average of 47 minutes (76%; p < 0.05). No medically important drug toxicity occurred. CONCLUSIONS: The results support the hypothesis that A(2A) receptor mechanisms contribute to symptom production in PD and that drugs able to selectively block these receptors may help palliate symptoms in levodopa-treated patients with this disorder.

Oculo-facio-cardio-dental (OFCD) syndrome.

The association of facial dysmorphy, congenital cataracts, microphthalmia, heart disease, and dental radiculomegaly is very rare. We describe a girl with atrial septal defect, unilateral congenital cataract, unilateral microphthalmia, radiculomegaly of incisor and canine teeth with open apices and other dental crown anomalies. This combination of symptoms clearly represents a distinct syndrome and has recently been described as oculo-facio-cardio-dental (OFCD) syndrome.

[Information level of mothers children from 0 to 3 years about the problems of stomatological prophylaxis]. / Prouchvane nivoto na informiranostta na maikite na actsa ot 0 do 3 godini po problemite na stomatologichnata profilaktika.

The information of the mothers as regards the possibilities of realization of complex prophylaxis of dental caries and periodontopathis is of great importance for such prophylaxis. The objective of this work is a sociological study, by the inquiry method, at the information level about those problems of 500 mothers of children, aged from 0 to 3 years in the town of Pernik. The results from the study reveal that the information level of the mothers is unsatisfactorily due to the insufficient work of the stomatologist in prenatal and well baby clinic. That raises the problem for exact regulation of prophylactic time of work with the pregnant and the mothers of little children.

[Comparative studies of the distribution of hepatitis B markers among blood donors and patients with post-transfusion hepatitis in the city of Sofia]. / Sravnitelni prouchvaniia vurkhu razprostranenieto na gepatitni B-markeri sred kruvodariteli i sred zaboleli ot posttransfuzionen khepatit v gr. Sofiia.

The incidence of HBsAg, anti-HBs, HBeAg and anti-HBe was studied in blood donor via various methods. HBsAg was established in 0.9 to 1.2% on the average among the blood donors paid; in 1.4 to 3.9% among the unpaid ones and 4.7 to 5.1% among the blood donors from organized population groups. Anti-HBs was established in 14.2%, HBeAg in 13.6% and anti-HBe in 38.2% from the HBsAg positive. With the comparative juxtaposition in the post-transfusion hepatitis (PTH) among the patients admitted to hospital for viral hepatitis a tendency was established to reduction from 0.9% for the period before the testing of the blood donors for HBsAg, 7.5% for the period tested by immunoelectrophoresis (IEP), and 4.5% for the period tested by reversal passive hemagglutination (RPHA). Patients HBsAg-positive were established by IEP in 39.2% on the average and by RPHA in 48.6%. A relative increase is reported of non-B PTH, non-A, non-B PTH in particular, with the introduction of more sensitive methods for investigations of blood donors for hepatitis B markers.

[Viral hepatitis associated with prolonged hemodialysis treatment]. / Virusniiat khepatit vuv vruzka s produlzhitelnoto khemodializno lechenie.

Viral hepatitis has a high incidence both among patients on hemodialysis and among the attending personnel. A clinical epidemiological study on hepatitis epidemic was carried out at the department of hemodialysis--Research Institute of Nephrology, Urology, Hemodialysis and Transplantation--for an eight-year period. Twenty two per cent of the patients were affected by hepatitis infection and 27.1 per cent of the personnel. The disease has, more often, a subclinical course in the patients on hemodialysis, manifested not later than one year after the initiation of hemodialysis treatment. The epidemic of viral hepatitis a chain of five epidemic outbreaks with a considerable predomination of HBsAg--positive forms. About 15 per cent of the patients on hemodialysis are chronic carriers of HBsAg, being, very likely, associated with the altered immune reactivity. All those data support the necessity of the introduction of a campaign programme against hepatitis epidemic.

Alterations in macroscopically intact skin of children with juvenile rheumatoid arthritis.

Punch biopsies of macroscopic-intact skin were performed on 75 children with rheumatoid arthritis, aged 4--14 years. There was no significant correlation between the morphologic alterations and the sex and age of the children or the duration of the disease, but there was a positive relationship with the degree of activity of the rheumatoid process. It appears that punch biopsy of the skin in children with juvenile rheumatoid arthritis can facilitate determination of alterations of the connective tissue if the data obtained are regularly correlated with clinical and laboratory findings. In such a way, the results can reflect the effects of treatment, as well as the evolution and prognosis of the juvenile rheumatoid arthritis.

[Efficacy of prolonged therapy with vitamins C and A and radiologic changes in the Ehlers-Danlos syndrome]. / Efficacité d'une thérapie prolongée aux vitamines C et A et modifications radiologiques dans le syndrome d'Ehlers-Danlos.

Two children of the same sex, almost of equal age, and suffering from the Ehlers-Danlos syndrome were followed up for a period of seven years. One of the children was subjected to a systematic treatment with vitamins C and A, Lipovitan, sulphuric mineral waters, and kinesitherapy. The non-treated child is serving as control person for the treated one. Thus it has been possible to evaluate the efficacy of the therapy administered to the first child and also to state the osseous progressive changes in the non-treated child.