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Biomedical subjects

B K Das

Publications and source records attributed to B K Das.

At least 19 recordsLinked to original sources

Incidence and characterization of Clostridium perfringens isolated from antibiotic-associated diarrhoeal patients: a prospective study in an Indian hospital.

Clostridium perfringens has been reported as causing between 2-15% of all cases of antibiotic-associated diarrhoea (AAD), and may be diagnosed by detection of enterotoxin in faeces. A prospective study comprising 150 diarrhoeal patients and 100 non-diarrhoeal controls was undertaken to assess the incidence of C. perfringens-associated diarrhoea in an Indian hospital. Methods used included C. perfringens culture, reverse passive latex agglutination (RPLA) and enzyme-linked immunosorbent assay (ELISA) for detection of enterotoxin, and polymerase chain reaction (PCR) assay for the presence of enterotoxin gene. Attempts were made to type the isolates by multiplex PCR. Of the 150 diarrhoeal stool samples tested, 13 were culture positive. Of these, four were positive for C. perfringens enterotoxin by RPLA, two were positive by PCR and two were positive by RPLA and ELISA. Twenty-seven samples were positive for culture of C. perfringens in non-diarrhoeal controls but none were positive for enterotoxin either by RPLA or by PCR. The average incidence of C. perfringens AAD using these methods was 2.6%. Toxin typing showed that all the isolates belonged to type A. To conclude, the relatively low incidence of toxigenic C. perfringens suggests that enterotoxigenic C. perfringens is not a major cause of AAD in this population.

Adolescent↗

Lipid peroxidation and antioxidants in neonatal septicemia.

Free radicals have been implicated in the pathogenesis of neonatal septicemia. The present study was planned to estimate the lipid peroxidation and antioxidant status in neonatal septicemia. The study was done to evaluate the lipid peroxidation and antioxidant status, both enzymatic and non-enzymatic in neonates with septicemia. This prospective study included 44 septicemic babies as cases and a group of 84 matched healthy babies formed the control. Malondialdehyde (MDA), Superoxide dismutase (SOD), Glutathione peroxidase (GTPx), Catalase, Uric acid (UA) and Albumin (Alb) were estimated in the serum and compared between the groups. The statistical analysis was done by using SPSS-10 software. Neonates with septicemia had significantly higher levels of MDA, SOD, GTPx, and Catalase, while the levels of UA and Alb were significantly lower as compared to controls (p<0.001). Significantly elevated levels of MDA (p<0.05) and depressed levels of UA (p<0.001) were found in babies with late onset sepsis. Neonates who ultimately succumbed had significantly elevated levels of MDA, SOD, GTPx and Catalase, whereas levels of UA and Alb were significantly depressed (p<0.001). Neonates with sepsis are handicapped in terms of their defense mechanism against free radicals. The utility of supplementation of antioxidant enzymes in neonates with septicemia needs further evaluation.

Antioxidants↗

Serotype distribution of Streptococcus pneumoniae isolates from ophthalmic and systemic infections and of commensal origin.

BACKGROUND AND OBJECTIVES: Information regarding serotype distributions of Streptococcus pneumoniae causing ophthalmic infections is scanty. This study was therefore undertaken to determine the antimicrobial susceptibility status and serotypes of S. pneumoniae isolated from various ophthalmic infections and to compare with those isolated from systemic infections and commensal nasopharyngeal flora. METHODS: Thirty eight of S. pneumoniae isolates from ophthalmic infections, 9 from systemic infections and 14 from the nasopharynx of apparently healthy school children were biochemically characterized and tested for in vitro antimicrobial susceptibility to various antibiotics. Serotyping of these 61 isolates was done by a rapid co-agglutination method. RESULTS: All the 61 isolates were sensitive to oxacillin (penicillin) and susceptibility against other antimicrobials was variable. No multidrug resistance was observed. The 38 ophthalmic isolates were distributed in 15 different serotypes. Most prevalent serotypes were 14, followed by 8 and 19F. The 9 systemic and 14 commensal. isolates of S. pneumoniae were distributed in 7 and 11 serotypes respectively. Three of the systemic and six of the commensal serotypes were observed in ophthalmic infections whereas four of the commensal serotypes were observed in systemic infections. INTERPRETATION AND CONCLUSION: Resistance to penicillin was not observed. In ophthalmic infections, a wide range of serotypes of S. pneumoniae were observed. More than half of the commensal serotypes obtained in the study as well as majority of the systemic serotypes were observed in ophthalmic infections.

Adolescent↗

Pyrexia of unknown origin with neutropenia, cervical lymphadenopathy, pneumonia and marrow hypoplasia.

A 56 years adult male presented with fever for 3 weeks with neutropenia and cervical lymphadenopathy with left sided pneumonitis. Histopathology of lymphnode was consistent with Kikuchi's Necrotizing Lymphadenitis. Kikuchi's disease is usually a self- limiting illness characterized by pyrexia, neutropenia and cervical lymphadenopathy in young women of Asian decent. This often leads to the misdiagnosis of lymphoma or tuberculosis. The notable feature here is an older male presented with severe neutropenia and pneumonia with hypoplastic marrow.

Bone Marrow Diseases↗

The immunomodulatory effects of tuftsin on the non-specific immune system of Indian Major carp, Labeo rohita.

The purpose of this study was to determine if injections of different dosages of tuftsin would enhance the immune response and disease resistance against the infections due to the opportunistic pathogens Aeromonas hydrophila and Edwardsiella tarda in Labeo rohita fingerlings. Hence, four different dosages of tuftsin in PBS suspension at the rate of 0, 5, 10, 15 mg kg(-1) body weight of fish were injected intraperitoneally to the fingerlings of L. rohita at 2-week intervals for four times. After every 2-week interval, different serum biochemical, haematological and immunological parameters of fish were evaluated. Biochemical and haematological parameters including serum total protein content, albumin content, globulin content, albulin:globulin ratio, glucose content, leucocyte counts etc.; cellular immune parameters including superoxide anion production, phagocytic activities, lymphokine production index etc.; humoral immune parameters including lysozyme activity, complement activity, serum bactericidal activity etc., in the fish were evaluated after every 2-week interval. After 56 days, fish were divided into two subgroups under each major treatment group for challenge with two pathogens A. hydrophila and E. tarda. The mortality (%) and agglutinating antibody titre was recorded on 28th day post challenge. Most of the immune parameters including leucocyte count, phagocytic ratio, phagocytic index, lysozyme activity, complement activity, and serum bactericidal activity were significantly (p<or=0.05) maximum on 42 days after three i.p. injections of 10 mg kg(-1) body weight of tuftsin. Challenge study indicated least mortality in the group of fish injected with 10 mg kg(-1) body weight of tuftsin for four times. Multiple injections of tuftsin might have maintained the activation of phagocytic cells for a long period, which in turn led to long-term protection in the fish. Thus, multiple injections of 10 mg kg(-1) body weight of tuftsin for three times can be advocated for enhancing the immune response of fish species under aquaculture.

Aeromonas hydrophila↗

Utility of random amplification of polymorphic DNA assay and BOX-A PCR in molecular characterization of Streptococcus pneumoniae isolates recovered from various ophthalmic infections.

BACKGROUND AND OBJECTIVES: Studies emphasizing the genotype distribution among ophthalmic isolates of Streptococcus pneumoniae are scarce. There is no conclusive information on genetic relatedness of the ophthalmic isolates with the commensal and systemic isolates of S. pneumoniae. METHODS: To find out the relatedness between the ophthalmic, invasive and commensal isolates of S. pneumoniae, genotyping was carried out by using RAPD and BOX-A PCR assays. The serotyping was carried out by a rapid co-agglutination method using 12-pooled S. pneumoniae antisera. RESULTS: Topological relationship was identified in order of similarity, and phylogenetic tree was drawn employing sequential clustering alogarithm by UPGMA linkage analysis. The 61 isolates were distributed in 17 RAPD types, 11 BOX-A types and 21 serotypes. CONCLUSIONS: Both genotyping techniques were useful in terms of intraspecies genomic variation in S. pneumoniae. BOX-A PCR typing was found to be slightly superior to RAPD analysis in terms of reproducibility and standardization. No specific S. pneumoniae serotype or genotype was found to have special predilection to cause ophthalmic infections.

Adolescent↗

Maternal anthropometry as predictors of low birth weight.

The usefulness of maternal anthropometric parameters i.e. maternal weight (MWt), maternal height (MHt), maternal mid-arm circumference (MMAC) and maternal body mass index (MBMI) as predictors of low birth weight (LBW) was studied in 395 singleton pregnancies. The maternal anthropometric parameters were measured in the first trimester of pregnancy and were plotted against the birth weight of the newborns. Significant positive correlations were observed among MWt and birth weight (r=0.38), MHt and birth weight (r=0.25), MMAC and birth weight (r=0.30) and MBMI and birth weight (r=0.30). The most sensitive being MWt (t=7.796), followed by MMAC (t=5.759), MHt (t=4.706) and MBMI (t=5.89). For prediction of LBW, the critical limits of MWt, MHt, MMAC and MBMI were 45 kg, 152 cm, 22.5 cm, 20 kg/m2 respectively. From these observations, the use of colour-coded weighing machines, height rods and tapes may be devised for use by peripheral health workers and traditional birth attendants for detection of mothers at risk of delivering low birth weight babies (Table 5). Mothers who have anthropometric parameters in the 'red zone' are at risk of delivery LBW infants.

Anthropometry↗

Effect of Achyranthes aspera on the immunity and survival of Labeo rohita infected with Aeromonas hydrophila.

Achyranthes aspera seed was incorporated in the diets (at 0.01%, 0.1% and 0.5%) of Labeo rohita, rohu fingerlings (3.0+/-0.4 g). After 2 weeks, the fish were immunized with heat-killed Aeromonas hydrophila, and after a further 2 weeks the rohu were experimentally infected with Aeromonas hydrophila (ATCC 49140). After 7 days blood and serum were sampled to determine superoxide anion production, bactericidal activity, lysozyme, serum protein, albumin, globulin, serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) and alkaline phosphatase (ALP). Superoxide anion production, serum bactericidal activity, lysozyme, ALP, serum protein, albumin:globulin ratio (A/G) were enhanced in Achyranthes treated groups compared to the control group. SGOT and SGPT levels were elevated in control group, but in Achyranthes treated groups the levels were similar to the uninfected-control group. Higher cumulative mortalities were observed in the control group (77%) up to day-9 after infection. This gradually decreased with increasing dose of Achyranthes, 66% mortality in 0.01% group, 57% mortality in 0.1% group and 28% mortality in 0.5% group. These results indicate that Achyranthes aspera stimulates immunity and increases resistance to infection in L. rohita.

Achyranthes↗

Effect of mannitol on regional cerebral blood flow in patients with intracerebral hemorrhage.

AIM: To evaluate the regional cerebral blood flow (rCBF) changes following IV mannitol bolus in patients with intracerebral hemorrhage (ICH). METHODS: In a hospital based randomized placebo controlled study, 21 CT proven ICH patients with Glasgow coma scale (GCS) score of 5 or more were subjected to clinical evaluation including GCS and Canadian Neurological stroke (CNS) scale. Cranial SPECT study was undertaken before and 60 min after 20% mannitol 100 ml IV in 20 min or sham infusion. The SPECT images were semi-quantitatively analyzed and asymmetry index of basal ganglia, frontal, parietal and occipital regions were calculated. RESULTS: There were 12 patients in mannitol and nine in control group who were evenly matched for age, mean arterial blood pressure, GCS score and size of hematoma. Only one patient died in mannitol group. Following mannitol, GCS score improved in six, worsened in two and remained unaltered in four patients. In the control group, GCS improved in seven, worsened in none and was unchanged in two patients. SPECT studies revealed reduction in asymmetry index in basal ganglia in four, frontal region in six, parietal in four and occipital region in five patients in mannitol group. In control group, asymmetry index was reduced in basal ganglia in one, frontal and parietal region in three each and occipital region in five patients. These differences between control and study group were not significant. CONCLUSION: Mannitol does not seem to significantly change the regional cerebral blood flow (rCBF) in ICH patients as evaluated by SPECT study.

Adult↗

Comparison of peritoneal equilibration test with 99mTc-DTPA excretion in the assessment of peritoneal permeability.

Assessment of peritoneal permeability is necessary for successful management of end-stage renal disease (ESRD) patients by continuous ambulatory peritoneal dialysis (CAPD). The objective of this study was to develop an alternative method of assessing the peritoneal permeability and to compare this method with the conventional method, the peritoneal equilibrium test, first described by Twardowski in 1987. Twenty patients undergoing regular CAPD were included in this study. Before starting the peritoneal dialysis, 370 MBq (10 mCi) technetium-99m diethylene triamine penta-acetic acid ((99m)Tc-DTPA) was injected intravenously. A standard dose of the same quantity was kept and used later for calculations. At the end of 4 h, a dialysate fluid sample (1 ml) was collected and the total dialysis effluent fluid volume was measured. Excretion of (99m)Tc-DTPA into the dialysate fluid as a percentage of the injected dose was calculated. Simultaneously, standard peritoneal equilibrium test values were recorded for comparison. Peritoneal excretion of (99m)Tc-DTPA ranged from 8% to 25% of the injected dose, depending on the peritoneal membrane permeability. When the results were compared with the conventional method, a good correlation (r=0.79) was found. This innovative radionuclide technique is a simple and convenient method to assess the peritoneal membrane permeability and can be used as an alternative to the peritoneal equilibrium test, which is very cumbersome and associated with many limitations.

Adult↗

Immune status with empyema thoracis.

OBJECTIVE: To evaluate the humoral and cell mediated immune status of children with empyema thoracis. METHODS: Serum IgG, IgA, IgM, Complement C3 assay and cell mediated immunity (CMI) tests were performed in 33 patients of empyema thoracis, and 14 healthy age matched controls. RESULTS: The mean serum IgG and IgA levels in empyema thoracis and its subgroups were significantly raised as compared to controls. The overall values of IgG and IgA were 104% (p<0.001) and 114% (p<0.01) of normal mean, respectively. The mean serum IgM and complement C3 levels did not differ significantly in both the groups. The frequency of negative skin reaction to purified protein derivative (PPD) was significantly higher in children with empyema thoracis as compared to controls (p<0.05). The mean absolute lymphocyte count (ALC) was significantly decreased and serum adenosine deaminase (ADA) activity was significantly raised in empyema thoracis in comparison to controls. The overall ALC was 76.1% (p<0.01) and serum ADA activity was 169.4% (p<0.001) of normal mean, respectively. No significant differences were observed in the mean levels of immunoglobulins, complement C3 and CMI tests between pyothorax and pyopneumothorax and pleural fluid culture positive and negative cases. CONCLUSIONS: Thus, both humoral and cell mediated immunity were affected in empyema thoracis patients. However, CMI demonstrated more pronounced change in comparison to humoral immunity.

Adenosine Deaminase↗

Nitrite toxicity in Indian major carps: sublethal effect on selected enzymes in fingerlings of Catla catla, Labeo rohita and Cirrhinus mrigala.

The effects of 96-h sublethal exposure of nitrite (1, 2, 4, 8 and 10.4 mg l(-1)) on selected enzymatic activities in serum and tissues of fingerlings of catla (Catla catla), rohu (Labeo rohita) and mrigal (Cirrhinus mrigala) were studied for the first time in these species. All three species responded almost identically to nitrite exposure. With increasing nitrite concentration, reduction in activities was observed in acetylcholinesterase (AChE) in brain and liver; alkaline phosphatase (ALP) in serum, brain and gill; and acid phosphatase (ACP) in gill, while progressive increase in alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT) activities in brain, gill and serum, and ACP activity in serum and brain was observed. Lactate dehydrogenase (LDH) activity increased in gill, liver, kidney, brain and serum of all three species with increasing nitrite concentration up to 8 mg l(-1) followed by reduction at 10.4 mg l(-1). The study revealed nitrite stress causing alteration in activities of all measured tissue and serum enzymes in the fingerlings, and so stresses the need for proper management of this particular nutrient in water during carp culture.

Acetylcholinesterase↗

The immunosuppressive effect of alpha-permethrin on Indian major carp, rohu (Labeo rohita Ham.).

The immunosuppressive effects of bath exposure to a sub lethal concentration of the synthetic pyrethroid alpha-permethrin (3.05 x 10(-4) mg l(-1)) in the Indian Major carp, Labeo rohita was studied after 45 days' exposure. In some groups, the effects of alpha-permethrin on non-specific defences and serum enzymes of carp were investigated after challenge with Aeromonas hydrophila. Several nonspecific immune responses and serum enzymes were reduced after exposure of alpha-permethrin. Bactericidal activity of rohu serum was reduced significantly in pesticide and bacteria treated fish. The Glutamic Oxaloacetate Transaminase (GOT) and Glutamic Pyruvate Transaminase (GPT) activity were increased in immunosuppressed fish. Blood glucose level was elevated significantly and Hb% was reduced significantly in pesticide and bacteria treated fishes as compared to the negative control.

Aeromonas hydrophila↗

Reduced susceptibility to ciprofloxacin and gyra gene mutation in North Indian strains of Salmonella enterica serotype Typhi and serotype Paratyphi A.

The emergence of reduced susceptibility to ciprofloxacin among Salmonella enterica serotype Typhi and serotype Paratyphi A leading to clinical failure of treatment poses a great therapeutic challenge. The mechanism of fluoroquinolone resistance in clinical isolates of S. Typhi and S. Paratyphi A is not very well documented. The present study was carried out with the objective of molecular characterization of reduced quinolone susceptibility amongst the strains of S. Typhi and S. Paratyphi A isolated from the patients with enteric fever during January, 2000, to April, 2003, in a North Indian hospital. A total of 422 culture-positive cases of enteric fever were reported to the hospital during the period of study, of which S. Typhi was isolated from 350 cases and S. Paratyphi A from 72 cases. The antimicrobial susceptibility of these strains was determined by disk diffusion and agar dilution method according to NCCLS guidelines, and E-test method. A total of 140 randomly selected strains, isolated during the years 1993-1999, that were available from the laboratory stocks were also studied to compare with the present strains. To study the quinolone susceptibility, the strains were divided into nalidixic acid sensitive (NAS), nalidixic acid intermediate resistant, (NAI) and nalidixic acid resistant (NAR) on the basis of susceptibility to nalidixic acid. Clinical history was available from 174 patients, of which 93 needed hospitalization due to severe disease. Of these, 82 patients were infected with NAR strains and 22 patients had a documented evidence of clinical failure to ciprofloxacin therapy. The patients infected with NAR strains were younger and had a significantly longer duration of fever (p value < 0.05) than those infected with NAS strains. It was observed that the proportion of NAR strains increased gradually over the years. These strains had a significantly higher range of MIC of ciprofloxacin (0.023-1.0 microg/ml) as compared to the NAS strains (0.002-0.125 microg/ml) (p value < 0.05). The sequencing of quinolone resistance determining region (QRDR) of the gyrA gene showed the presence of mutation at either Ser 83 or at Asp 87 in all the NAR and NAI strains. None of the NAS strains had a mutation, suggesting that the gyrA gene mutation is sufficient to confer resistance to nalidixic acid and reduced susceptibility to ciprofloxacin. This mutation, although phenotypically expressed as decreased susceptibility to ciprofloxacin, goes undetected by the disk diffusion method using the present NCCLS guidelines. Hence, it can increase morbidity and mortality due to delay in appropriate antibiotic treatment.

Adolescent↗

Serum immunoglobulin E in idiopathic nephrotic syndrome.

Serum immunoglobulin E (IgE) and absolute eosinophil count (AEC) were assayed in 48 children with idiopathic nephrotic syndrome and 20 controls. The mean serum IgE (p < 0.001) and AEC (p < 0.05) were significantly raised in active nephrotic syndrome compared with controls. The mean values of IgE and AEC in nephrotic patients were 228.6 and 164.5 per cent of the normal mean, respectively. The serum IgE and AEC were significantly abnormal in all the subgroups (first attack, infrequent, and frequent relapsers), except AEC in infrequent relapses, when compared with the controls. No significant differences in the parameters were observed among the different subgroups of cases. In remission, the mean IgE and AEC were unchanged in comparison with their corresponding values at diagnosis. Thus, the levels are raised not only in active but also in remission, reflecting abnormal immune status even in the disease-free state.

Case-Control Studies↗