Synthesis And Characterisation Of CdxZn1–xS Nanocomposites

CdxZn1 – xS nanoparticles have been synthesized using hydrothermal method. Structural characterization was done by XRD where the lattice structure gradually changes from hexagonal to cubic with increasing percentage of Zn inCdxZn1 – xS nanoparticles. Optical spectroscopy provided evidence that the absorption edges of those nanoparticles can be varied from blue to UV. The nanoparticles exhibit emission peaks that shift to shorter wavelength with increasing percentage of Zn in the compounds CdxZn1 – xS. The control of the composition of CdxZn1 – xS nanoparticles may lead the development of ideal materials for short wavelength diode laser applications. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/951

Synthesis and Characterisation Of CdxZn1–xS Nanocomposites

CdxZn1 – xS nanoparticles have been synthesized using hydrothermal method. Structural characterization was done by XRD where the lattice structure gradually changes from hexagonal to cubic with increasing percentage of Zn inCdxZn1 – xS nanoparticles. Optical spectroscopy provided evidence that the absorption edges of those nanoparticles can be varied from blue to UV. The nanoparticles exhibit emission peaks that shift to shorter wavelength with increasing percentage of Zn in the compounds CdxZn1 – xS. The control of the composition of CdxZn1 – xS nanoparticles may lead the development of ideal materials for short wavelength diode laser applications

Emerging problems of antibiotic resistance in community medicine

Emergence of antimicrobial resistance in bacteria associated with community acquired infections has made the choice of empirical therapy more difficult and more expensive. The problems due to possible spread of MRSA to the community, emergence of penicillin resistance in S. pneumoniae, ampicillin resistance in H. influenzae, and multiresistance among common enteric pathogens are highlighted. Bacteria have a remarkable ability to develop resistance to many of the newly synthesized antimicrobial agents but the appropriate use of antibiotics will delay and in many cases prevent the emergence of resistance

Childhood invasive pneumococcal disease: a hospital-based study from Malaysia

Aim: New conjugate vaccine for Streptococcus pneumoniae has been introduced in Malaysia recently. Information on infection due to S. pneumoniae in Malaysian children is scarce. We conducted a retrospective chart review of childhood invasive pneumococcal disease (IPD) presented to a single centre in Malaysia. Methods: A retrospective review of 5 years and 4 months of all cases of IPD in children younger than 14 years of age (May 1999-August 2004) seen at the University of Malaya Medical Centre (UMMC), Kuala Lumpur, was conducted. Cases were identified from the record of Department of Medical Microbiology, UMMC. Results: IPD was identified in 50 children (median age 1.1 years, range 2 weeks-14 years) during the study period. Seventy-six per cent of the cases were younger than 2 years of age. Pattern of infections noted include definite pneumonia (n = 8), probable pneumonia (n = 33), meningitis (n = 4), bacteraemia without focus (n = 4) and septic arthritis (n = 1 each). Pre-morbid diseases were present in 28 of all cases. Complications (n = 12, 24) due to IPD were seizures (n = 5), pleural effusion/empyema (n = 4), cerebral palsy (n = 2) and deafness (n = 1). No deaths were attributed to IPD. Sixty-two per cent of the pneumococcal isolates were penicillin non-susceptible and were detected throughout the study period. Conclusions: IPD is associated with high morbidity, particularly among young children. Majority of the isolates were penicillin-non-susceptible strains. Additional information on the serotype of S. pneumoniae isolated is necessary to assess the potential impact of immunisation on preventing pneumococcal infection in Malaysia

Extra-intestinal non-typhoidal Salmonella infections in children

Extra-intestinal non-typhoidal Salmonella (NTS) infections are uncommon in developed countries but common in developing ones. The risk factors, clinical features and outcome of children admitted to the Department of Paediatrics, University of Malaya Medical Center, Kuala Lumpur from 1978 to 1998 with extra-intestinal NTS infections were reviewed. All positive cultures of NTS, blood, cerebrospinal fluid, urine, synovial, pericardial and other body secretions (except stools), were included. Of the 98 cases reviewed, 56 were boys and 42 girls. The mean age was 2.1 years (range: newborn to 14 years). Twenty-seven children were severely immunocompromised and 21 had underlying chronic medical disorders. Bacteraemia was the most commonly detected type of infection and meningitis the commonest focal infection. The overall mortality rate was 15. An immunocompromised stare or underlying chronic medical disorder was associated with increased mortality. The three serotypes most commonly isolated were S. enteritidis, S. paratyphi B and S. typhimurium. Most isolates were sensitive to antibiotics commonly used in salmonellosis

Antimicrobial susceptibility and distribution of non-typhoidal Salmonella serovars isolated in Malaysian children

There is widespread resistance of Salmonella species to commonly prescribed antimicrobials the world over. We aimed to determine the antimicrobial susceptibility and serovar distribution of non-typhoidal Salmonella (NTS) isolated from blood cultures of Malaysian children. Positive isolates of NTS from blood cultures obtained from children admitted to the pediatric wards of University of Malaya Medical Center (UMMC), a large urban hospital from Kuala Lumpur (1991-2001), and Hospital Kota Bharu (HKB), from the predominantly rural state of Kelantan (1991-1999), Malaysia, were reviewed retrospectively. Serovar distribution and antimicrobial susceptibility were ascertained. A total of 64 and 55 isolates of NTS were obtained from blood cultures of children admitted to UMMC and HKB, respectively. The commonest serovar isolated was Salmonella enteritidis in both centers. The NTS isolated were highly sensitive to the antimicrobials tested: ampicillin 98 per cent, chloramphenicol 98 per cent, gentamicin 97 per cent, trimethoprim-sulfamethoxazole (TMP-SMX) 98 per cent, and ceftriaxone 100 per cent in UMMC; ampicillin 100 per cent, chloramphenicol 87 per cent, kanamycin 100 per cent, streptomycin 96 per cent, TMP-SMX 93 per cent, and tetracycline 89 per cent in HKB. There were only one and five multi-resistant isolates in UMMC and HKB, respectively. In conclusion, NTS isolated from blood cultures of Malaysian children from Kuala Lumpur and Kota Bharu were highly sensitive to commonly prescribed antibiotics. We speculate that this is due to the restriction of sales of antimicrobials in Malaysia except by prescription. Continuing vigilance and frequent antimicrobial surveillance is necessary