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Biomedical subjects

A Ghosh

Publications and source records attributed to A Ghosh.

At least 55 records · Page 3Linked to original sources
PubMed2004

Isolation and partial structural evaluation of a cardiotoxic factor from Indian common murrel (Channa striatus L.) skin extract.

It was earlier reported from this laboratory that, Channa striatus, L a common edible fish, whose skin extract (CSSE) was pharmacologicaclly potent and contains several bioactive compounds. In the present communication a cardiotoxic factor was isolated and purified by thin layer chromatography followed by silica gel and neutral alumina column chromatography. Spectroscopic studies (UV, IR, 1H and 13C NMR, FAB-MS) indicated that the lethal cardiotoxic factor (CSS-CTF II) was an aromatic alkaloid compound with -NH, > C = C < and -OH functional groups. The molecular weight was found to be 413 dalton. LD50 of CSS-CTF II was found to be 42.5 mg/kg (i.v) in Swiss albino male mice. Pharmacological studies showed that CSS-CTF II possesses hypotensive and cardiotoxic activities and produced death through apnoea in experimental animals but had no effect on nerve muscle preparations. The haematological and biochemical data also indicated the toxic nature of CSS-CTF II, through significant fall in haemoglobin, total RBC, WBC, platelet count and increased cardiac marker enzyme CPK and CPK-MB value in experimental animals. The present investigation thus established the toxic nature of CSS-CTF II isolated from edible fish C. striatus skin extract. Further work is needed to identify CSS-CTF II's mechanism of action and its antagonism for therapeutic purpose.

Animals↗
PubMed2004

Arthropathic presentation of Wilson's disease.

A patient is described who presented with polyarthritis involving small and large joints of limbs with later onset of tremors affecting all four extremities. Investigations including genetic study confirmed the diagnosis of Wilson's disease (WD). The case highlights the importance of considering the possibility of WD in young patient presenting with repetitive unexplained joint symptoms with or without tremor.

Adult↗
PubMed2004

A study to determine the pharmacokinetics of gatifloxacin following a single oral dose.

Gatifloxacin is a broad spectrum fluoroquinolone that offers enhanced Gram-positive activity and anaerobic coverage to other fluoroquinolones. The pharmacokinetic parameters (Cmax, AUCo-t, tmax) of this drug have been evaluated to compare the single dose (400mg) bioavailability of gatifloxacin with the reference formulation. High performance liquid chromatography (HPLC) coupled with U-V detector set at 290 nm has been used to determine plasma concentration of 12 human volunteers as per DCGI (Drug Controller General of India) guidelines. The method has been validated over a linear range of 0.25 to 8 microg/ml from plasma. The minimum quantifiable concentration has been set at 0.25 microg/ml (% CV < 10%). The pharmacokinetic parameters are: Cmax = 4.366 +/- 0.44 microg/ml at tmax = 1.83 +/- 0.44 hour, AUCO0-t = 25.26 +/- 2.91 microg hour/ml, AUCo-inf = 33.68 +/- 4.31 microg hour/ml, Kel = 0.094 +/- 0.024/hour and t1/2 = 8.0 +/- 1.92 hour.

Administration, Oral↗
PubMed2003

The peritrophic matrix limits the rate of digestion in adult Anopheles stephensi and Aedes aegypti mosquitoes.

The peritrophic matrix (PM) is a chitin-containing acellular sheath that surrounds the blood meal and separates the food bolus from the midgut epithelium. Intense molecular traffic through the PM occurs during digestion. Digestive enzymes secreted by the midgut epithelium must traverse the PM to reach their substrates in the food bolus, and digestion products must cross the PM in the opposite direction to be absorbed by the epithelial cells. Here we report that the PM limits the rate of digestion. PM disruption by two independent means (chitinase and anti-PM antibodies) consistently increases the rate of blood digestion. The significance of these results in relation to PM function is discussed.

Aedes↗
PubMed2003

Apophysomyces elegans: an emerging zygomycete in India.

Apophysomyces elegans was considered a rare but medically important zygomycete. We analyzed the clinical records of eight patients from a single center in whom zygomycosis due to A. elegans was diagnosed over a span of 25 months. We also attempted a DNA-based method for rapid identification of the fungi and looked for interstrain polymorphism using microsattelite primers. Three patients had cutaneous and subcutaneous infections, three had isolated renal involvement, one had rhino-orbital tissue infection, and the final patient had a disseminated infection involving the spleen and kidney. Underlying illnesses were found in two patients, one with diabetes mellitus and the other with chronic alcoholism. A history of traumatic implantation was available for three patients. All except two of the patients responded to surgical and/or medical therapy; the diagnosis for the two exceptions was made at the terminal stage of infection. Restriction enzyme (MboI, MspI, HinfI) digestion of the PCR-amplified internal transcribed spacer region helped with the rapid and specific identification of A. elegans. The strains could be divided into two groups according to their patterns, with clustering into one pattern obtained by using microsatellite [(GTG)(5) and (GAC)(5)] PCR fingerprinting. The study highlights the epidemiology, clinical spectrum, and diagnosis of emerging A. elegans infections.

Adult↗
PubMed2003

Towards evidence based emergency medicine: best BETs from the Manchester Royal Infirmary. Glucagon for the treatment of symptomatic beta blocker overdose.

A short cut review was carried out to establish whether the intravenous glucagon can support blood pressure in beta blocker overdose. A total of 51 papers were found using the reported search, of which six presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these best papers are tabulated. A clinical bottom line is stated.

Adrenergic beta-Antagonists↗
PubMed2003

Opportunistic screening for genital chlamydial infection. I: acceptability of urine testing in primary and secondary healthcare settings.

OBJECTIVES: To determine the acceptability of opportunistic screening for Chlamydia trachomatis in young people in a range of healthcare settings. DESIGN: An opportunistic screening programme (1 September 1999 to 31 August 2000) using urine samples tested by ligase chain reaction (LCR). Data on uptake and testing were collected and in-depth interviews were used for programme evaluation. SETTING: General practice, family planning, genitourinary medicine clinics, adolescent sexual health clinics, termination of pregnancy clinics, and women's services in hospitals (antenatal, colposcopy, gynaecology and infertility clinics) in two health authorities (Wirral and Portsmouth and South East Hampshire). Main participants: Sexually active women aged between 16 and 24 years attending healthcare settings for any reason. MAIN OUTCOME MEASURES: Uptake data: proportion of women accepting a test by area, healthcare setting, and age; overall population coverage achieved in 1 year. Evaluation data: participants' attitudes and views towards opportunistic screening and urine testing. RESULTS: Acceptance of testing by women (16-24 years) was 76% in Portsmouth and 84% in Wirral. Acceptance was lower in younger women (Portsmouth only) and varied by healthcare setting within each site. 50% of the target female population were screened in Portsmouth and 39% in Wirral. Both the opportunistic offer of screening and the method of screening were universally acceptable. Major factors influencing a decision to accept screening were the non-invasive nature of testing and treatment, desire to protect future fertility, and the experimental nature of the screening programme. CONCLUSIONS: An opportunistic model of urine screening for chlamydial infection is a practical, universally acceptable method of screening.

Adolescent↗
PubMed2003

Opportunistic screening for genital chlamydial infection. II: prevalence among healthcare attenders, outcome, and evaluation of positive cases.

OBJECTIVES: To determine the prevalence and treatment outcomes among young women screened opportunistically for genital Chlamydia trachomatis and to evaluate the impact of screening in those participating. DESIGN: An opportunistic screening programme (1 September 1999 to 31 August 2000) using urine samples, tested by ligase chain reaction (LCR). In-depth interviews were used for programme evaluation. SETTING: Screening was offered in two health authorities at general practice, family planning, genitourinary medicine (GUM), adolescent sexual health, termination of pregnancy clinics and women's services in hospitals (antenatal, colposcopy, gynaecology and infertility clinics). Main participants: Sexually active women (16-24 years) attending for any reason. MAIN OUTCOME MEASURES: Screening data: prevalence of infection by age and healthcare setting; proportion of positive patients attending for treatment. Evaluation data: participants' attitudes and views towards screening and follow up. RESULTS: In total, 16 930 women (16-24 years) were screened. Prevalence was higher in younger women (16-20) than those aged 21-24 years and was highly variable at different healthcare settings (range 3.4%-17.6%). Prevalence was approximately 9% in general practice. The role of the project health advisers in managing results and coordinating treatment of positive individuals was essential; the vast majority of all positives were known to be treated. Women felt that screening was beneficial. Improving awareness and education about sexually transmitted infections is required to alleviate negative reactions associated with testing positive for infection. CONCLUSIONS: Prevalence of infection outside GUM clinics is substantial and opportunistic screening using urine samples is an acceptable method of reaching individuals with infection who do not normally present at specialist clinics.

Adolescent↗
PubMed2002

Evaluation of the management of optic neuritis: audit on the neurological and ophthalmological practice in the north west of England.

The management of acute optic neuritis by neurologists and ophthalmologists in the north west of England was assessed in the light of the Optic Neuritis Treatment Trial (ONTT) recommendations. A questionnaire on a fictitious case of typical unilateral optic neuritis was mailed to all consultant ophthalmologists and neurologists working in the North West and Merseyside Health Authorities. They were then asked to comment on management of the case. Fifty two out of 86 ophthalmologists and 20 out of 28 neurologists replied. The overall response rate was 63%. Sixty five per cent of neurologists and 46% of ophthalmologists would investigate a typical case of acute optic neuritis further. Forty six per cent of neurologists and 36% of ophthalmologists were likely to arrange MRI of the brain or orbit. Significantly more neurologists (55%) than ophthalmologists (9%) chose to treat with intravenous methylprednisolone (p<0.005). Significantly more ophthalmologists (64%) than neurologists (32%) chose not to give steroids (p<0.025). Oral prednisolone alone was rarely selected for treatment. Respondents were more likely to discuss multiple sclerosis with the referring doctor than with the patient. Only 32% of ophthalmologists and 20% of neurologists would clearly mention the possibility of improvement to the patient. Clear differences in practice between ophthalmologists and neurologists remain. A consensus on practice guidelines on the issues raised might be useful.

Acute Disease↗
PubMed2002

Effect of dextrans on cryopreservation of goat cauda epididymal spermatozoa using a chemically defined medium.

Experiments were carried out to investigate the cryoprotecting potential of dextrans (ranging from 10 to 2000 kDa) using a synthetic model system developed recently in this laboratory. Goat spermatozoa from the cauda epididymidis were extracted in a chemically defined medium (modified Ringer's solution) and assayed for motility using a phase-contrast microscope. The sperm cells were subjected to a freezing protocol in a computer-controlled biofreezer (cooling at 0.25 degrees C min(-1) to 5 degrees C; 5 degrees C min(-1) to -20 degrees C; 20 degrees C min(-1) to -100 degrees C) and plunged into liquid nitrogen. The frozen cells were thawed rapidly at 37 degrees C in a thermostatic waterbath. In the absence of dextran, all the spermatozoa lost their motility. The cryoprotecting efficacy of each dextran was found to be biphasic in nature. Initially, as the concentration of dextran was increased, the recovery of sperm motility also increased and reached an optimum value; however, with further increases in dextran concentration, the recovery of motility decreased sharply. Of all the sugar polymers tested, 10 kDa dextran showed the highest cryoprotecting efficacy, whereas the 2000 kDa sugar polymer was the least active. Dextrans of 10, 40, 73, 173, 252, 500 and 2000 kDa offered maximum cryorecovery of forward motility to the extent of approximately 23%, 21%, 19%, 18%, 16%, 15% and 8%, respectively. Optimum concentrations of these dextrans for cryoprotection of sperm motility were 8.42, 2.50, 1.09, 0.37, 0.31, 0.10 and 0.04 mmol l(-1), respectively. It thus appears that each dextran has a characteristic cryoprotection profile. The data show that the cryoprotecting efficacy and optimum cryoprotecting concentrations of dextrans are inversely related to their molecular mass. Dextran also served as a significant cryoprotectant in the presence of glycerol (0.87 mol l(-1)) and dimethyl sulphoxide (0.76 mol l(-1)), which are well known cryoprotectants; the action of the combined cryoprotectants was almost additive. The presence of glycerol or glycerol plus dimethyl sulphoxide caused a significant reduction (from 8.42 to 6.27 mmol l(-1)) in the optimum concentration of dextran. In the presence of the three cryoprotectants, recovery of sperm motility was as high as 58% (forward motility) and 60% (total motility).

Animals↗
PubMed2002

Physiological characters of Sporothrix schenckii isolates.

Sporotrichosis is endemic in three regions (east, north and south) in India. The colony morphology and physiological characteristics of 49 clinical isolates from these three regions (25 from north India, 17 from east India and seven from south India) were analysed in both mycelial and yeast forms. No difference in colony character was seen among the 49 isolates on three different media. Growth of all isolates was inhibited at 40 degrees C. The yeast forms were found to be more tolerant to osmotic pressure and salt concentrations. Most mycelial forms grew well between pH 3-12.0 whereas most yeast forms could tolerate a pH range of 2.4 to 9.5. Variations in assimilation of arabinose, dextrin, raffinose, rhamnose and starch was observed among strains from different geographical regions. The yeast forms did not show any urease activity but the mycelial forms of all isolates could split urea. Phenol oxidase and potassium nitrate assimilation were positive and gelatinase activity and casein hydrolysis were negative for all isolates.

Carbohydrate Metabolism↗
PubMed2002

Change in distribution & antifungal susceptibility of Candida species isolated from candidaemia cases in a tertiary care centre during 1996-2000.

BACKGROUND & OBJECTIVES: As a marked increase in the number of patients with candidaemia was reported in the first half (1991-1995) of the last decade at the Postgraduate Institute of Medical Education & Research, Chandigarh, India, the present study was aimed at determining further change if any, in the incidence and distribution of Candida species and their antifungal resistance pattern during the second half (1996-2000) of the same decade. METHODS: The patients with candidaemia were studied to determine the frequency of candidaemia and Candida species isolated during 1996-2000. One hundred Candida strains other than Pichia anomala (C. pelliculosa) were randomly selected from those isolates to evaluate antifungal susceptibility pattern against amphotericin B, 5-fluorocytosine, ketoconazole, fluconazole and itraconazole. The results were compared with our previous study. RESULTS: An increase in the number of patients with candidaemia was observed during 1996 (538) and 1997 (421) compared to 1998-2000 due to P. anomala outbreak. With the control of the outbreak, a substantial decrease in the incidence of candidaemia was observed from 1998 (251 in 1998, 122 in 1999 and 165 in 2000). A higher isolation of non-C. albicans Candida species (89.8%) was observed, with C. tropicalis being the most common (541, 36.1%) agent. No major change in the isolation rate of other non-C. albicans Candida species (C. guilliermondii, C. krusei, C. glabrata and C. parapsilosis) was observed. An emergence of resistance to amphotericin B in 15.4 per cent C. albicans, 8.1 per cent C. tropicalis and 33.3 per cent C. krusei strains was observed. An increase in resistance to ketoconazole (from 0% to 13%) and 5-fluorocytosine (from 1% to 8%) and a decrease to fluconazole (from 13% to 6%) were observed. Resistance to itraconazole was observed in 17 per cent of Candida strains by broth macro-dilution method. INTERPRETATION & CONCLUSION: A change in the isolation of Candida species was observed i.e. in the incidence and isolation of non-C. albicans Candida species. Emergence of resistance to amphotericin B and increase of resistance to most other antifungals are cause for concern.

Antifungal Agents↗
PubMed2002

Mannan antigen detection in the diagnosis of patients with invasive candidiasis.

BACKGROUND & OBJECTIVES: With the increase in the incidence of invasive candidiasis (IC) in recent years, there is a need to improve the sensitivity of diagnosis. A conventional technique like blood culture is positive in nearly 50 per cent of cases. To improve the diagnostic efficiency in invasive candidiasis mannan antigen detection holds promise. Hence mannan antigen detection was evaluated in patients with suspected invasive candidiasis in the Paediatric Intensive Care Unit (PICU). METHODS: A prospective study, involving 186 consecutive patients admitted to the PICU of the Advanced Paediatric Center at the Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh between March 1999 and November 1999 were followed up for possible invasive candidiasis. Sixty five children clinically suspected to have sepsis and at risk for developing IC and or who stayed in the hospital more than 5 days were further evaluated for the diagnosis of IC by collecting two blood culture samples 48 h apart and by mannan antigen and anti-mannan antibody detection. Both antigen and antibody were detected by in-house standardized techniques: antibody by whole cell agglutination (WCA) and antigen by sandwich enzyme linked immunosorbent assay (ELISA). RESULTS: Twenty of 65 patients (30.7%) were positive by blood culture. Mannan antigen was positive in all 20 patients and significant anti-mannan antibody titre (> or = 128) was present in 12 (60%) patients. Mannan antigen was detected in 15 more patients, who were negative for isolation of Candida from blood. Twelve of these patients had febrile episode not responding to antibacterial therapy but responding to fluconazole/itraconazole therapy indicating that the patients possibly had IC. Mannan concentration was also found to be significantly higher in the patients with Candida isolated from blood. INTERPRETATION & CONCLUSION: Thus, the present study confirms the earlier claim that mannan antigen detection possibly improves the diagnostic efficiency of IC.

Adolescent↗