In-silico screening of high production volume chemicals for mutagenicity using the MCASE QSAR expert system.

Computational screening is suggested as a way to set priorities for further testing of high production volume (HPV) chemicals for mutagenicity and other toxic endpoints. Results are presented for batch screening of 2484 HPV chemicals to predict their mutagenicity in Salmonella typhimurium (Ames test). The chemicals were tested against 15 databases for Salmonella strains TA100, TA1535, TA1537, TA97 and TA98, both with metabolic activation (using rat liver and hamster liver S9 mix test) and without metabolic activation. Of the 2484 chemicals, 1868 are predicted to be completely nonmutagenic in all of the 15 data modules and 39 chemicals were found to contain structural fragments outside the knowledge of the expert system and therefore suggested for further evaluation. The remaining 616 chemicals were found to contain different biophores (structural alerts) believed to be linked to mutagenicity. The chemicals were ranked indescending order according to their predicted mutagenic potential and the first 100 chemicals with highest mutagenicity scores are presented. The screening result offers hope that rapid and inexpensive computational methods can aid in prioritizing the testing of HPV chemicals, save time and animals and help to avoid needless expense.

Febrile episode among a floating population of C.R.P.F. Jawans stationed at Calcutta.

A virological investigation was carried out to establish the etiologic agent of a febrile outbreak amongst a floating population of C.R.P.F. Jawans, stationed at Calcutta during May-July, 1993. The illness was associated with fever, severe headache, bodyache and arthralgia which lasted for 2-4 days in most of the cases. Fifty cases were examined clinically and blood samples (both acute and convalescent) were subjected to virological study. One mouse-pathogenic agent could be isolated in suckling mice and identified as DEN-3. Sero-investigation of 50 single sera by HI & CF method revealed evidence of presumptive dengue infection in 33, while sero-conversion could be noted in 10 out of 25 available paired sera tested. Results of MAC ELISA revealed evidence of primary dengue infection in 6 out of 12 acute phase sera examined. Thus, the study shows that the episode is strongly suggestive of primary dengue infection.

Serosurvey of chikungunya antibody in Calcutta metropolis.

Since its first isolation in Calcutta, in 1963, there have been many reports about epidemis of chikungunya virus infection in different parts of India. Calcutta experienced a concurrent epidemic of dengue and chikungunya between 1963 and 1965. But after that there is no report about any chikungunya infection in Calcutta. During routine investigations it is found that chikungunya antibody is on the wane. The present survey for chikungunya antibody showed only 4.37% (n = 17) seropositivity out of 389 sera tested. The highest (12.5%) seropositivity was observed in the age group of 51-55 years and no chikungunya antibody was detected in young and young adults. The findings suggest that chikungunya virus is disappearing from the Calcutta population.

A serological survey of influenza a antibody in human and pig sera in Calcutta.

A study was undertaken with a view to assess the distinct pattern of sero-prevalence of influenza A viruses in the city of Calcutta population during the years of 1981-90. Concurrently, based on the fact of increasing pig population, a study was carried out to establish the activity of the human influenza A virus among pigs with a view to the potential threat of emergence of a new strain of influenza A virus that may surface following co-infection with swine and human influenza A viruses. The percentage positivity of the H3N2 antigen was found to be highest (46%), followed by H1N1 (43%), H2N2 (35%) and H0N1 (19%). A similar pattern was noted with pig sera.

Dengue haemorrhagic fever (DHF) outbreak in Calcutta--1990.

An outbreak of Dengue Haemorrhagic Fever (DHF) occurred in Calcutta between September and December, 1990. Children and young adults were the major victims. Haemorrhagic manifestations and shocks were the main features in most of the hospitalised cases. Five mouse pathogenic agents were isolated from 105 acute cases and all were identified as DEN-3. HI and CF test with 55 paired sera revealed evidence of dengue infection in 33 (60 per cent) and flavivirus group reaction including dengue in 17 (30.9 per cent). It was for the first time, that DEN-3 was considered to be the etiologic agent for DHF in Calcutta.

Once-daily controlled release remoxipride is equieffective with twice-daily immediate release remoxipride in the treatment of schizophrenia.

A controlled release (CR) formulation of remoxipride (Roxiam(®), Astra) given once-daily was compared to immediate release (IR) remoxipride given twice-daily, with respect to efficacy and tolerability, in a 4-week multicentre parallel-group dose titration (200-600 mg/day) study with acutely ill schizophrenic patients. Forty- three patients received remoxipride CR (mean dose 344 mg/day) and 49 patients received remoxipride IR (mean dose 346 mg/day). Efficacy was assessed using the Kolakowska version of the Brief Psychiatric Rating Scale (BPRS score of ≥ 18 points at entry) and the Clinical Global Impression scale (CGI), while extrapyramidal symptoms were rated using the Simpson and Angus scale. Both formulations of remoxipride produced clinical improvement, with the BPRS median total score falling from 35 at baseline to 16 at last rating in the remoxipride CR group, and from 33 to 12.5 in the remoxipride IR group. More than 70% of the patients in both groups were assessed as 'much improved' or 'very much improved' according to the CGI scale. Both formulations of remoxipride were well-tolerated, with a low incidence of treatment-emergent adverse symptoms, including extrapyramidal side effects. No statistically significant differences were detected between the treatment groups with regard to efficacy, safety or tolerability.

Recurrent outbreaks of Japanese encephalitis in Nagaland (1985-1989)--a seroepidemiological study.

Recurrent epidemics of encephalitis in Nagaland, a North-Eastern State of India, following its first appearance in 1985, were investigated both epidemiologically and virologically. Although, no viral agent could be isolated from any of the clinical samples and mosquitoes, detection of JE specific IgM antibodies in many of the CSF and acute blood samples, together with presence of HI and CF antibodies to JE antigen in a number of acute and convalescent sera established the etiologic role of JE virus in this region. A total number of 83 clinically diagnosed cases could only be investigated virologically between 1985-89, where evidence of JE could be established in 34 (40.9 per cent) and flavivirus (including JE in majority) in 17 (21.5 per cent) cases. A limited serological survey among the close contacts of the victims in 1985 revealed JE antibody in 26.6 per cent of them. Analysis of the epidemiological and serological findings of different years revealed that while the outbreaks of 1985, 1987 and 1988 were due to JE infection, the episodes of 1986 and 1989, on the other hand, had chiefly features of high and prolonged fever with limited number of CNS involvement of undetermined origin, where the possibility of malarial infection has been a suspect apart from JE etiology.

Zuclopenthixol acetate (5% in 'Viscoleo'): single-dose treatment for acutely disturbed psychotic patients.

Twenty-five acutely disturbed psychotic patients were treated in an open study with a single injection of zuclopenthixol acetate 5% in 'Viscoleo, a thin vegetable oil. Patients were assessed post-injection for 3 days using the BPRS, CGI, and a specially designed behaviour/activity scale. Doses of 50 to 150 mg proved effective in 24 (96%) of 25 patients, with pronounced and rapid reduction in psychotic symptoms over the study period. The mean total BPRS score after 72 hours was reduced by over 57%. Tranquillization and sedation appeared within 15 to 90 minutes of injection. Unwanted symptoms were generally mild and of low incidence. The results showed that a single injection of zuclopenthixol acetate 5% in 'Viscoleo' provided rapid tranquillization and sedation coupled with an antipsychotic effect over 3 days. This profile offers a distinct advantage over neuroleptic preparations conventionally used for the initial treatment of acutely disturbed psychotic patients.

Outbreak of febrile illness due to dengue virus type 3 in Calcutta during 1983.

An epidemic of dengue fever broke out in Calcutta between July and August 1983. Persons of all age groups were affected with a preponderance of young adults. Haemorrhagic manifestations and shock were not observed. Virus was isolated from 4 acute phase sera and identified as dengue type 3 (DEN-3), the first isolation of DEN-3 virus in Calcutta. Serotesting with 9 paired blood samples established dengue infection in 7 and a flavivirus group reaction in 2. Examination of 36 single sera revealed presumptive dengue infection in 15 and a flavivirus group reaction in 17, while the remaining 4 were negative to all flavivirus antigens.

The tolerance and antidepressive activity of fluvoxamine as a single dose compared to a twice daily dose.

A double-blind study was carried out in 62 hospital out-patients suffering from mild to moderate depression to investigate the efficacy and tolerance of fluvoxamine given as a single daily dose or in divided doses. Patients were allocated at random to receive 100 mg fluvoxamine either as a single daytime dose, a single night-time dose or as 50 mg twice daily over a period of 6 weeks after a 1 week wash-out period on placebo. Patients were assessed using the Hamilton and Montgomery Asberg depression rating scales and the Clinical Global Impression scale before and during treatment. All three dosage regimens produced significant improvement and no significant difference was found in antidepressive effect between the groups. However, patients receiving a single night-time dose experienced fewer side-effects leading to drop-out before the end of the study than in the other two groups.