The activities of hepatic drug metabolizing enzymes and lipid peroxidation during treatment with an organophosphorus insecticide, Take 20 were studied in young growing male rats. It was found that when the animals were treated with low and medium doses 100 mg/kg, 150 mg/kg and 200 mg/kg the liver weights, relative liver weights and drug metabolizing enzymes were increased, however, the liver protein content was decreased. High doses of Take 20, 300 mg/kg and 400 mg/kg resulted in decrease of liver weights, relative liver weights and drug metabolizing enzymes, though the liver protein content was increased, thereby indicating that the protein synthesis and enzyme activities were behaving in an entirely different manner. The enzymatic and non enzymatic lipid peroxidations were decreased with low and medium doses and increased with high doses, indicating that the animals can no longer adapt to the toxic effects.
Background & objectives:
Hydroxyethyl starches (HES) 130/0.4 (Voluven®) and 130/0.42 (Venofundin®) impair coagulation less than older HES solutions with higher molecular weight and molar substitution. Thus, these may be used in high doses up to 50 ml/kg/day. The aim of this study was to investigate and compare the effects of HES 130/0.4 versus HES 130/0.42 on coagulation after the intraoperative infusion of 30 ml/kg in patients undergoing major abdominal surgery.
Fifty two patients scheduled for elective major abdominal surgery were randomized to receive 30 ml/kg of HES 130/0.4 or HES 130/0.42 intraoperatively. Coagulation variables were assessed before and after infusion of the colloid solution using thrombelastography.
Data from 49 patients, 25 patients in the HES 130/0.4 and 24 in the HES 130/0.42 group, were analyzed. Measurements of reaction time, kinetic time, α-angle, maximum amplitude and coagulation index before and after colloid infusion did not differ between the groups. Within each group, after colloid infusion, reaction time did not change significantly, while α-angle, maximum amplitude and coagulation index values were significantly decreased (P<0.01, P<0.001 and P<0.001, respectively in HES 130/0.4 group and P<0.01, P<0.001 and P<0.01, respectively in HES 130/0.42 group). Kinetic time was significantly increased (P<0.001) in both the groups. In both groups, all thrombelastographic measurements after colloid infusion were found within normal limits.
Interpretation & conclusions:
HES 130/0.4 and HES 130/0.42 showed similar, not clinically significant effects on coagulation, as assessed by thrombelastography, when a dose of 30 ml/kg was administered in patients undergoing major abdominal surgery.
Insecticide in the form of space spray as an ultra low volume (ULV) aerosol are used during epidemics of vector borne diseases. Deltacide, a formulation comprising of three chemicals viz., deltamethrin 0.5 per cent w/v, S-bio-allethrin 0.71 per cent w/v and piperonyl butoxide 8.9 per cent w/v is suitable for ULV application. As this combination is found to be effective in preventing resistance development tackling the population, which had already developed resistance and cause immediate mortality, its synergistic effect was tested in Peet Grady chamber, against three species of mosquitoes, viz., Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus.
Blood fed females were exposed to ULV application of deltacide in a Peet Grady chamber at four dosages viz., 0.005, 0.01, 0.02 and 0.04 ml/m2 and examined for knockdown activity at 10 min interval for 60 min. Thereafter, the mosquitoes were removed from the chamber and maintained in another room having controlled temperature (28+/-2 degrees C) and humidity (60-75%) and observed for recovery, if any, and the per cent knockdown was calculated. Mortality rate after 24 h of holding period was also determined from moribund and dead adults.
Pairwise comparison showed that the effect of deltacide spray varied significantly (P<0.001) among the three species tested. The effectiveness was significantly higher in Ae. aegypti, when compared with that of Cx. quiquefasciatus (P<0.001) and An. stephensi (P<0.05). However, there was no significant difference in the efficacy of deltacide between Cx. quiquefasciatus and An. stephensi. All species of mosquitoes became inactive i.e., knocked down completely within 60 min of exposure at all the dosages tested and mortality observed was 100 per cent after 24 h of exposure.
Deltacide when tested in the form of ULV cold aerosol, the dosage 0.01 ml/m2 was effective against both Ae. aegypti, and An. stephensi, and 0.02 ml/m2 against Cx. quiquefasciatus, causing 100 per cent mortality. The efficacy of ULV application of deltacide against vector mosquitoes needs to be assessed under field conditions.
A total of 538 strains of V. cholerae 01 biotype ElTor were phage typed by the conventional Basu and Mukerjee and also the new typing scheme developed at the National Institute of Cholera and Enteric Diseases, Calcutta. The strains could be clustered into seven types by the new scheme as against only two by the conventional method. The results provide conclusive evidence on the validity of the new scheme for phage typing of V. cholerae strains.
A characterisation of the biochemical and physiological properties of 30 strains of non 01 V. cholerae isolated from faecal samples, was undertaken. The strains consistently expressed a large number of characters that define them to be closer to the El Tor biotype than their classical counterparts. They did not show much heterogeneity in their cultural and biochemical properties. The strains were strongly haemolysing (100%), haemagglutinating (96%) and also salt-tolerant, thereby acquiring a unique taxonomic status.
During the recent epidemic of cholera in Madras from October-December 1992, a total of 11,100 patients with acute secretory diarrhoea have been admitted to the Communicable Diseases Hospital, Madras, when compared to a total of 2,440 patients admitted during the pre-epidemic period studied between January - September 1992. A novel strain of non-01 V. cholerae was found to be the most predominant agent during the epidemic period. A representative sample of 84 non-01 strains isolated during the epidemic period were confirmed as V. cholerae non-01 and newly designated as serogroup 0139 at National Institute of Cholera and Enteric Diseases, Calcutta. All 84 strains of non-01 were found to elaborate cholera toxin (CT). Fourteen strains were also confirmed as serogroup 0139 from our non-01 stock recovered during the pre-epidemic period. Of the 17,540 patients admitted during the post epidemic period, studied from January 1993 - June 1994, 3.8 and 37.8 per cent patients were infected by 01 and non-01 serogroup 0139 respectively. The new serogroup 0139 continued to be the predominant isolate even during the post epidemic period.
Data accumulated over the past 20 yr (1969-88) on the phage typing of V. cholerae 01 biotype ElT or strains received at the Vibrio Phage Reference Laboratory, were retrospectively analysed to ascertain the frequency of occurrence of the different phage types of Basu and Mukerjee typing scheme. The analysis revealed that phage types 2 and 4 were the most common types not only at the time when the Basu and Mukerjee typing scheme (of 1968) was introduced but also at present. The existing phage typing scheme needs to be improved with the addition of more new phages to obtain more type distinction and better discrimination within biotype ElT or strains for epidemiological studies.
The enterotoxicity of the new cholera toxin (NCT) prepared from cholera toxin gene-negative (CT-) V. cholerae 01 strains isolated from human diarrhoeal and environmental sources was assayed in rabbit ileal loops and the toxin unit was calculated to be 24 micrograms of protein. The enterotoxicity of the NCT preparations were completely neutralised by the antiserum raised against the enterotoxin preparation from the CT+ V. cholerae 01 strain 569B at 1 in 16 dilution in ileal loops. The antiserum contained 1 unit of antitoxin in 85 x 10(-4) ml amount. The data indicate that the antiserum prepared against the enterotoxin of CT+ strain contains antibody against the NCT and can neutralise the toxin in vivo. The observations also suggest that CT+ strains liberate the NCT simultaneously with CT and the latter gets eliminated during the process of purification.
During May-June 1993, an outbreak of acute diarrhoea resulting in deaths primarily in adults was reported in two districts of Orissa state. Epidemiological and microbiological investigations revealed that this outbreak was caused by V. cholerae 01 biotype EITor. V. cholerae 01 strains were uniformly resistant to furazolidone.
A total of 514 samples of acute diarrhoeal stools received over a period of four months yielded 315 isolates morphologically and biochemically resembling V. cholerae. Out of 315 isolates, 223 (70.8%) were identified as V. cholerae 01, 20 (6.4%) as 0139 and 42 (13.3%) as 010. Thirty (9.5%) isolates did not agglutinate with any of the available antisera. All V. cholerae 010 isolates showed complete homogeneity in their biochemical and physiological properties. This strain appears to be closely related to El Tor biotype of V. cholerae 01, since it was positive for some of the tests used for identification of El Tor. The ability of strain 010 to grow in the presence of 6 per cent salt provides it the status of an important environmental pathogen. Acquisition of some virulence genes from El Tor vibrios by this strain 010 appears to be one of the mechanisms involved in the emergence of this serogroup.
A total of 34 strains of V. cholerae were isolated during March to July, 1993. Of the 34 V. cholerae isolated 26 strains were non 01 and remaining eight were 01 El tor vibrio. Non-01 strains were identified as novel epidemic strains designated as 0139. The shift in the relative and absolute prevalence of V. cholera serotype 01 and non 01 was noted.
Five V. cholerae 0139 phages isolated from different parts of India have been used for phage typing study. A strain isolated from Nagpur city (NPR-4) was used as the host for phage propagation. All but one of the 260 strains of V. cholerae 0139 were found to be typeable and could be clustered into 8 distinct phage types as revealed by lytic patterns. Phage type 1 was the predominant type (61.15%) followed by type 2 (18.46%). The strains isolated from Madras exhibited 7 out of 8 phage types. These newly isolated phages could be adopted for phage typing of V. cholerae 0139 strains as an epidemiological tool.
In an outbreak of acute watery diarrhoea, 11 strains of V. cholerae were isolated in May-June 1993 at Medical College, Rohtak. Eight of these belonged to serogroup Ogawa and three were identified as V. cholerae serogroup 0139. This is the first report of isolation of this novel serotype from this region.
We compared the conventional culture method with the coagglutination (CoA) test for detecting V. cholerae 0139 antigen in a 4 h faecal enrichment culture. The CoA test reacted positively in all 13 culture positive stool specimens from patients with clinical cholera and negatively in all 23 culture negative specimens from non-diarrhoeal healthy controls. The test also did not show cross reaction with V. cholerae 01 antigen or with any of the enterobacterial antigens of the coliforms. The CoA test was found to be technically simple, rapid and reliable in diagnosing V. cholerae 0139 infection.
A total of 44 strains of Vibrio 0139 serotype isolated between April and August 1993 at Sevagram (Wardha) were examined for expression of a number of biochemical and physiological characteristics. All strains fermented lactose within 24 h and belonged to Heiberg group III. Salt tolerance to 8 per cent NaCl was seen in 22.72 per cent strains. Haemolysis of sheep RBCs and haemagglutination of human 'O', chicken and rabbit RBCs was consistently positive. All the strains were sensitive to tetracycline and resistant to polymyxin B and cotrimoxazole.
The confirmation of the identity of Vibrio cholerae serogroup 01 and serogroup 0139 is usually done by slide agglutination tests using specific antisera. Antiserum to V. cholerae 01 is freely available but not antiserum to V. cholerae 0139, thus making specific identification of the latter more difficult. A modified CAMP (Christie Atkins and Muench - Paterson) test has been described as a possibility in the identification of V. cholerae 0139 and we have evaluated this on 197 strains of organisms including 48 V. cholerae 0139, 50 V. cholerae 01, 49 non-01, non-139 V. cholerae and 50 Aeromonas species. The test had a sensitivity of 98.9 per cent and a specificity of 92.9 per cent in the identification of these strains, when compared with faeces culture as the gold standard.
A new clone of non-01 V. cholerae designated as serogroup 0139, which produces cholera toxin, was detected first in south India in September 1992 and has spread to many parts of India since then. It was identified in Bangladesh in December 1992 and in Thailand in April 1993. By May 1993 it was found in Haryana and Punjab. Its clinical manifestations are typical of cholera, occurring in outbreaks. This clone has largely replaced the previously prevalent 01 V. cholerae in several cholera endemic areas indicating that a new cholera pandemic has begun.
As one of large outbreaks of cholera-like illness in the Indian subcontinent, Calcutta and its neighbouring areas experienced an unprecedented epidemic due to a new strain of V. cholerae non-01, designated as V. cholerae 0139 Bengal, since January 1993. This epidemic predominantly affected the adult population of Calcutta as evidenced by the hospitalization of more adults at the Infectious Disease Hospital, Calcutta (IDH), which bore the main brunt of the epidemic in and around Calcutta. During the peak of the epidemic about 180 to 300 diarrhoea patients were admitted daily at the IDH. Of the 807 patients screened, 407 were positive for V. cholerae 0139 and majority (82.8%) of the cases were > 10 yr of age. Severe dehydration was recorded in 85.5 per cent of the cases.
Cell-associated haemagglutinating activity was detected in all the epidemic strains of V. cholerae 0139 and 01, isolated in different parts of the country, with erythrocytes from rabbit, rat, chicken and guinea pig. Sheep erythrocytes were unresponsive to both groups of strains. While D-mannose, alpha-methyl-D-mannoside, glucosamine, N-acetyl-D-glucosamine, thyroglobuline were effective inhibitors of the haemagglutinating activity of the V. cholerae 0139 and 01 strains, galactose and N-acetyl-D-galactosamine sensitive haemagglutinins (HAs) were detected in the V. cholerae 01 but not in the V. cholerae 0139 strains. The best medium for expression of HAs in V. cholerae 01 and 0139 strains were observed to be penassay broth and tryptic soy broth respectively. The expression of HA in V. cholerae 01 was stimulated by Ca++ and Fe in the growth medium unlike that of V. cholerae 0139 which remained unaffected by these ions.
Cortisol response to 250 micrograms adrenocorticotropin (ACTH) exhibits no circadian variation. Information on the circadian variation, if any, in cortisol response to 1 microgram ACTH, which is considered as a physiological dose is not available. As the 1 microgram ACTH stimulation test is projected as an outpatients procedure with no time constraint, this information is very important. Hence, this study was designed to assess whether any circadian variability exists in cortisol response to 1 microgram ACTH in healthy subjects.
Thirty six healthy volunteers (23 male and 13 female) with mean age of 32.2 +/- 9.0 yr were consecutively studied after obtaining informed consent. On day 1, prestimulated and stimulated plasma cortisol samples were collected at 0800 h and, at 30 and 60 min following an intravenous bolus of 1 microgram ACTH, and on day 3, plasma cortisol samples were similarly collected at 1600 h. Cortisol estimation was done by a sensitive and specific radioimmunoassay. Stimulated plasma cortisol of 500 nmol/1 or more was defined as a normal response.
The prestimulated and peak cortisol levels at 0800 h (377.5 +/- 93.3 and 729.1 +/- 183.2 nmol/l) were higher (P < 0.001 and P < 0.01) than those at 1600 h (230.1 +/- 75.7 and 665.8 +/- 138.6 nmol/l). However, a stimulated cortisol response of 500 nmol/l or more was observed at both 0800 h and 1600 h in all subjects at 30 min but not at 60 min. The [symbol: see text] (peak-basal) response was higher at 1600 h than that at 0800 h (432.8 +/- 136.8 vs 351.5 +/- 177.3, P < 0.01).
The demonstration of normal cortisol response to 1 microgram ACTH both at 0800 h and 1600 h suggests that the test can be performed at any time of the day.