Anti-biofilm efficacy of silver nanoparticles against MRSA and MRSE isolated from wounds in a tertiary care hospital.

Purpose: Different approaches have been used for preventing biofi lm-related infections in health care settings. Many of these methods have their own de-merits, which include chemical-based complications; emergent antibiotic resistant strains, etc. The formation of biofi lm is the hallmark characteristic of Staphylococcus aureus and S. epidermidis infection, which consists of multiple layers of bacteria encased within an exopolysachharide glycocalyx. Nanotechnology may provide the answer to penetrate such biofi lms and reduce biofi lm formation. Therefore, the aim of present study was to demonstrate the biofi lm formation by methicillin resistance S. aureus (MRSA) and methicillin resistance S. epidermidis (MRSE) isolated from wounds by direct visualisation applying tissue culture plate, tube and Congo Red Agar methods. Materials and Methods: The anti-biofi lm activity of AgNPs was investigated by Congo Red, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) techniques. Results: The minimum inhibitory concentration (MIC) was found to be in the range of 11.25-45 μg/ml. The AgNPs coated surfaces effectively restricted biofi lm formation of the tested bacteria. Double fl uorescent staining (propidium iodide staining to detect bacterial cells and fl uorescein isothiocyanate concanavalin A (Con A-FITC) staining to detect the exopolysachharides matrix) technique using CLSM provides the visual evidence that AgNPs arrested the bacterial growth and prevent the glycocalyx formation. In our study, we could demonstrate the complete anti-biofi lm activity AgNPs at a concentration as low as 50 μg/ml. Conclusions: Our fi ndings suggested that AgNPs can be exploited towards the development of potential anti-bacterial coatings for various biomedical and environmental applications. In the near future, the AgNPs may play major role in the coating of medical devices and treatment of infections caused due to highly antibiotic resistant biofilm.

A comparative clinical trial of artemether and quinine in children with severe malaria.

OBJECTIVE: To compare the efficacy of artemether and quinine in the treatment of severe malaria in hospitalized children. STUDY DESIGN: Open randomized trial. SETTING: Pediatric ward of a tertiary care center. METHODS: All children admitted with clinical manifestations of severe malaria (as per WHO criteria) and asexual forms of Plasmodium falciparum demonstrated on peripheral smear were randomized to receive either artemether or quinine. Their clinical status and smears for parasite count were assessed every 12 hours until two successive blood films were negative. The primary end point of the study was death in the hospital and residual damage to the organ involved. The secondary end points were clearance of parasites and fever, length of time of recovery from coma and normal functions of the involved system. RESULTS: Forty-six cases completed the study protocol, 23 assigned to each drug group. Cerebral malaria was the commonest manifestation (76.1%). Mean age in artemether versus quinine group (6.6 +/- 3.5 and 5.8 +/- 2.4 years) as well as degree of parasitemia at admission (55,800 and 60,300 per microlitre) were comparable. The overall mortality rate was 23.9% with no significant difference between the two groups. Twenty six cases (56.5%) presented with more than one manifestations of severe malaria. The mortality rate was 100% with four coexisting manifestations of severe malaria. Fever clearance time in artemether and quinine group was 44.5 and 45.9 hours respectively (P >0.05). Parasite clearance time was significantly shorter in artemether group (40.9 vs. 51.9 hours; P<0.001). Recovery from coma was shorter in artemether group (34.8 vs. 38.1 hours; P<0.05). CONCLUSION: Cerebral malaria is the most common manifestation of severe malaria in children. Artemether is a good alternative drug to quinine for P. falciparum malaria. Mortality rate is directly proportional to the number of coexisting manifestations of severe malaria.

Nosocomial Klebsiella infection in neonates in a tertiary care hospital: protein profile by SDS-page and klebocin typing as epidemiological markers.

PURPOSE: To find out the prevalence of Klebsiella in hospital acquired neonatal infections in a tertiary care set up and to evaluate the role of klebocin typing and protein profile by SDS-PAGE in epidemiological typing of the isolates. METHODS: Hospital born neonates transferred to the neonatal unit after birth and available in the unit 48 hours later comprised the study group. Two hundred and three neonates were found eligible for inclusion in the study. Repeated blood cultures, other relevant clinical specimens and environmental samples were collected and identified according to the standard techniques. Isolated clinical and environmental Klebsiella pneumoniae strains were subjected to klebocin typing and protein profiling by SDS-PAGE at regular intervals. RESULTS: Multi drug resistant K. pneumoniae were the commonest organism isolated in 30 neonates leading to the incidence of Klebsiella nosocomial infection to be 14.7%. Klebocin typing of the K. pneumoniae isolates showed four patterns with type 312 being the commonest (43.4%). Whole cell protein analysis by SDS-PAGE of K. pneumoniae isolates revealed four types of banding pattern. Analysis of the typing method showed that the typeability and reproducibility of klebocin was 83.3% and 73.3% respectively whereas typeability and reproducibility of SDS-PAGE was 100%. CONCLUSIONS: Based on the present study it is concluded that SDS-PAGE typing method is better than klebocin typing in neonatal nosocomial infection. It is also suggested that protein profile by SDS-PAGE may be used as a tool for epidemiological typing of Klebsiella pneumoniae isolates in laboratories where genomic based molecular typing technique is not available.

Prevalence of malaria in Aligarh.

In Aligarh Plasmodium vivax and Plasmodium falciparum infections during 1998 and 1999 were 69.6% and 62.2%, and 30.4% and 37.8%, respectively. Peak transmission of malaria with highest slide positivity rates (38-44.6%) and slide P. falciparum rates (13 to 16%) were recorded during the months of September and October. About 7.5 to 10% cases showed resistance to chloroquine in P. falciparum infections while 11.3 to 16% P. vivax cases relapsed after getting required doses of chloroquine. About 75% of relapsing cases were of short-term type. Patients who were given both chloroquine and primaquine also relapsed but frequency was less (3.17%). A few chloroquine resistant cases were recorded in patients suffering from vivax malaria.

Biochemical studies on mouse liver following Plasmodium berghei infection.

The lipid composition of mouse liver following infection with P. berghei was investigated. The liver lipid contents of infected animals were greatly increased mainly due to the accumulation of triacylglycerides. There was enhanced lipid concentration (85.29%). Significantly (23.7%) depleted liver cholesterol was also found in the mice. Similarly, phospholipid contents of liver were also decreased by 19.90 per cent. The liver from P. berghei infected mouse produced more lipid peroxide, as compared to control animals (314%). Significant depletion was also observed in carbohydrate, glycogen and glucose (79.1, 86.26 and 78.6% respectively) contents of liver at high parasitaemia. The lower contents of nucleic acid in the infected hosts observed in the study may be partly due to the absorption of nucleic acids by the parasites from the host cells.

Clinical therapeutic analysis of vitiligo phase--II.

The incidence of vitiligo varies from country to country. In the present study, seventy cases of vitiligo have been studied from skin out patient department of the Institute of Post-graduate Medicine & Research over a period of 2 years. The prevalence rate of vitiligo among the total out patient attendent was 0.4 per cent. 85 per cent of the cases belonged to the age group to 11-40 years. Male and female ratio was 2:1. Precipitating factors like physical injury, mental stress and strain had close link with development of skin lesion. In 11.4 per cent cases near relations were involved. Skin lesions according to the site showed lower extremity to be the maximally involved area and the genital areas were least involved.

Incidence of cutaneous diphtheria in Bangladesh.

Corynebacterium diphtheriae (C. diphtheriae) was isolated from 23 (7%) skin ulcers out of 327 cases studied. Eight (33%) of the 23 positive cases belonged to the age group of 6 to 10 years. Of the 19 strains of C. diphtheriae typed, 18 (95%) were gravis and of which 14 (77%) were toxigenic. More than 90% of the C. diphtheriae positive ulcer cases had serum anti-toxin level at or above the protective level as against 49% of control. No diphtheria bacilli were isolated from throat of any of the skin positive cases. All the ulcers from which C. diphtheriae were isolated also harboured other definite wound pathogens. It is believed that the presence of toxigenic C. diphtheriae in skin wound might play an important role in the spread of faucial diphtheriae. It is evident from serum anti-toxin level that infected persons develop natural immunity.

Incidence of urethritis in Bangladesh.

Urethritis is either gonococcal or non-gonococcal. This paper describes the investigation of 286 cases of urethral or vaginal discharges, dysuria or urethral irritation. Non-gonococcal urethritis (NGU) was found to be the commonest form of urethritis accounting for 65.05 per cent of cases. Gonococcal urethritis (GU) and abacterial urethritis were accounted for 24.47 per cent and 10.48 per cent of cases respectively. No history of sexual exposure was found in 21.27 per cent of cases with NGU, whereas this was invariably present in cases of GU. This may indicate that in at least some of the patients with NGU, the disease may not be sexually transmitted. This point needs further study.

Post-Kala-azar dermal leishmaniasis ( a review of 10 cases).

Ten cases of Post-Kala-azar Dermal Leishmaniasis (PKDL) have been studied. The sites of involvement and morphological character have been noted. Skin scraping, biopsy, serological and biochemical changes have been looked for. Presence of visceral leishmaniasis along with PKDL had been searched. Response to therapy with antimony compounds have been observed and found satisfactory. Visceral leishmaniasis although not frequent now a days, the incidence of PKDL is still prevalent to some extent in this country.