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J Perera

Publications and source records attributed to J Perera.

At least 19 recordsLinked to original sources
PubMed2004

Introduction of nurse led DC cardioversion service in day surgery unit: prospective audit.

PROBLEM: Atrial fibrillation is the most common persistent arrhythmia in adults and carries an increased risk of thromboembolism and stroke. Electrical (DC) cardioversion is an effective treatment, but logistical difficulties in many institutions lead to problems providing a prompt service. This reduces the rate of long term success, delays relief of symptoms, and increases the burden on anticoagulation clinics. DESIGN: Prospective audit of introduction of a collaborative, nurse led DC cardioversion service in a day surgery unit. SETTING: Day surgery unit 5 km from an acute hospital in southeast London. KEY MEASURES FOR IMPROVEMENT: Waiting times, success of procedures, and complication rates. STRATEGIES FOR CHANGE: Collaborative working across traditional specialty boundaries; empowerment of patients within the process; using a nurse consultant as a single point of reference to coordinate the service. EFFECTS OF CHANGE: Sinus rhythm was restored in 131 (92%) of the first 143 patients treated. Three patients needed hospital admission; all were discharged uneventfully within 24 hours. No important complications occurred. Waiting times were reduced from 27 weeks to eight weeks for patients eligible for the service. LESSONS LEARNT: Elective DC cardioversion under general anaesthesia can be safely done by an appropriately trained nurse in a day surgery unit remote from an acute general hospital. This model of care is effective and can reduce waiting times and relieve pressure on acute beds and junior doctors.

Aged↗
PubMed2003

Methicillin-resistant Staphylococcus aureus: prevalence, incidence and risk factors associated with colonization in Sri Lanka.

We studied the prevalence of and risk factors for nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) on admission and the incidence and risk factors for nosocomial acquisition of MRSA in a 60 bed, male surgical unit in the National Hospital of Sri Lanka (NHSL). Nasal swab cultures were obtained from 271 patients admitted for routine surgery within 36 h of admission and repeated every other day until discharge. Clinical and epidemiological risk factors for colonization were compared between patients with MRSA at the time of admission or colonized after admission, and patients who were not colonized. MRSA was isolated from 35 patients (12.9%) with 20 (7.4%) colonized on admission and 15 (6%) acquiring MRSA after admission. Hospitalization within the previous year, antibiotic use within the previous two months, and transfer from another ward within the NHSL were associated with colonization with MRSA on admission. Risk factors for nosocomial acquisition of MRSA were the prophylactic and empiric use of antibiotics. The duration of antibiotic use and the duration of stay in hospital were significantly longer in patients who acquired MRSA. MRSA surveillance and control programmes in this unit would be more cost-effective if targeted at patients with these risk factors.

Adolescent↗
PubMed2003

Seroprevalence of rubella antibodies among pregnant females in Sri Lanka.

The purpose of this study was to determine the seroprevalence of rubella antibodies among pregnant females in the Kalutara District of Sri Lanka, and to identify factors associated with susceptibility to rubella infection among pregnant females. A cross-sectional clinic-based study was conducted among 620 pregnant women attending antenatal clinics and residing in the district for more than one month. Data on the pregnant females and the socio-economic characteristics of the families were obtained using an interviewer-administered structured questionnaire. Three milliliters of blood was obtained to measure rubella-specific IgG antibody levels by ELISA (enzyme linked immunosorbent assay) tests. Overall, 76% of pregnant females were seropositive for rubella antibodies. Seropositivity in pregnant females increased with age. Susceptibility to rubella was significantly associated with rubella immunization status. Given the high susceptibility rate to rubella infection among pregnant females, it is imperative that any vaccination strategy in the short-term should focus on reducing the number of susceptible women of child-bearing age.

Antibodies, Viral↗
PubMed2002

Strategies for immunisation against rubella: evidence from a study in the Kalutara District.

OBJECTIVE: To simulate different immunisation programs against rubella and estimate the proportion of the population susceptible to rubella infection of each. METHODS: The impact of 3 immunisation schedules on the susceptibility of women of childbearing age and the community to rubella infection was simulated using a probabilistic approach. The first schedule involved selective immunisation of 12-year old girls, the second immunisation of all children at 3 years of age for different immunisation coverages, and the third comprised a combination of the first two. The proportion of different segments of the population currently susceptible to rubella was obtained from a field study conducted in the Kalutara District in 1999. RESULTS: An immunisation program of 12-year old girls will reduce the susceptibility to rubella in 5 years in only the 15 to 19 year age group. In 10 years, the susceptibility in both the 15 to 19 and 20 to 24 year age groups will be reduced. Immunisation only of children at 3 years will take 20 years for a reduction in the susceptibility to rubella infection in the 15 to 19 year and the 20 to 24 year age groups, and the proportion of the population susceptible to rubella can be reduced to less than 10% in 20 years if 90% coverage is attained. If a combination of the two strategies i.e. selective immunisation of girls at 12 years for 10 years and immunisation of all children at 3 years is adopted, the proportion of the community susceptible to rubella will be less than 14% in 10 years. CONCLUSIONS: The combination of immunising girls at 12 years of age for 10 years and all children at 3 years of age against rubella is recommended for Sri Lanka to reduce the risk of congenital rubella syndrome in the short term and the proportion susceptible to rubella in the community in the long term.

Adult↗
PubMed2001

Carriage of antibiotic-resistant pneumococci among Asian children: a multinational surveillance by the Asian Network for Surveillance of Resistant Pathogens (ANSORP).

To investigate the nasal carriage of antibiotic-resistant pneumococci by children, anterior nasal swabs were done for 4963 children <5 years old in 11 countries in Asia and the Middle East. In total, 1105 pneumococci isolates (carriage rate, 22.3%) were collected, 35.8% of which were found to be nonsusceptible to penicillin. Prevalence of penicillin nonsusceptibility was highest in Taiwan (91.3%), followed by Korea (85.8%), Sri Lanka (76.5%), and Vietnam (70.4%). Penicillin resistance was related to residence in urban areas, enrollment in day care, and a history of otitis media. The most common serogroups were 6 (21.5%), 23 (16.5%), and 19 (15.7%). The most common clone, as assessed by pulsed-field gel electrophoresis, was identical to the Spanish 23F clone and to strains of invasive isolates from adult patients. Data in this study documented the high rate of penicillin or multidrug resistance among isolates of pneumococci carried nasally in children in Asia and the Middle East and showed that this is due to the spread of a few predominant clones in the region.

Anti-Bacterial Agents↗
PubMed2000

pT3.2I, the smallest plasmid of Thiobacillus T3.2.

The whole nucleotide sequence of pT3.2I, the smallest plasmid of the acidophilic bacterium Thiobacillus T3.2, has been determined. pT3.2I is 15,390 bp long with a 53.7% GC content. Different regions can be defined in it: one 2569-bp putative insertion sequence similar to other insertion sequences of some Agrobacterium Ti plasmids; and a longer sequence, which occurs in two almost identical copies, differing only in a 1-bp deletion (6406 and 6405 bp). Several open reading frames and some smaller sequences were found in this duplicated region: ORFA and ORFG, encoding a putative polyol dehydrogenase and a putative RepA replication protein, respectively, an 83-bp sequence which could code for an antisense RNA, and a 36-bp region highly homologous to ori sequences of ColE2- and ColE3-related plasmids. Another putative gene, ORFH, is only present in the longer copy of this region (it is deleted in the short copy) and might encode a 90-amino-acid polypeptide which could act as a second replication protein, RepB. Based on sequence comparisons, pT3. 2I can be related to plasmids in the pColE2-CA42 incB incompatibility group.

Amino Acid Sequence↗
PubMed1999

The mer operon of the acidophilic bacterium Thiobacillus T3.2 diverges from its Thiobacillus ferrooxidans counterpart.

The chromosomal mercury resistance (mer) region of the acidophilic bacterium Thiobacillus T3.2 was cloned, characterized, and compared to reported homologous sequences. The Thiobacillus T3.2 mer resistance system is organized as an operon that transcribes into a polycistronic mRNA encoding the Hg2+ ion transport MerT and MerP proteins and the mercuric reductase MerA. In contrast to the Thiobacillus ferrooxidans mer determinant, no merC gene was detected. Transcription of structural genes is regulated by the product of the regulatory merR gene. On the basis of sequence data and expression experiments in E. coli, both merTPA and merR transcription units could be located close to each other and in different strands, with their promoters (PTPA and PR, respectively) overlapping the putative MerR binding site in the intergenic operator/promoter (O/P) region. Amino acid sequences of mer gene products were compared to their homologs. Some sequence features, such as the number and position of cysteine residues, are unique for the Mer proteins of this bacterium. Similarities (-10 and -35 boxes are 19bp apart in both PR and PTPA promoters) and differences (inverted repeats in the Thiobacillus T3.2 MerR-binding site are 2bp shorter than in Thiobacillus ferrooxidans) exist between the O/P intergenic regions of both Thiobacilli. In vivo experiments showed inducible expression of mercury resistance in E. coli cells transformed with the entire Thiobacillus T3.2 mer genetic determinant (structural plus regulatory genes), and little or no expression in clones containing only the structural merT, merP, and merA genes.

Amino Acid Sequence↗
PubMed1999

Spread of drug-resistant Streptococcus pneumoniae in Asian countries: Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study.

Antimicrobial susceptibility of 996 isolates of Streptococcus pneumoniae from clinical specimens was investigated in 11 Asian countries from September 1996 to June 1997. Korea had the greatest frequency of nonsusceptible strains to penicillin with 79.7%, followed by Japan (65.3%), Vietnam (60.8%), Thailand (57.9%), Sri Lanka (41.2%), Taiwan (38.7%), Singapore (23.1%), Indonesia (21.0%), China (9.8%), Malaysia (9.0%), and India (3.8%). Serotypes 23F and 19F were the most common. Pulsed-field gel electrophoresis (PFGE) of 154 isolates from Asian countries showed several major PFGE patterns. The serotype 23F Spanish clone shared the same PFGE pattern with strains from Korea, Japan, Singapore, Taiwan, Thailand, and Malaysia. Fingerprinting analysis of pbp1a, pbp2x, and pbp2b genes of 12 strains from six countries also showed identical fingerprints of penicillin-binding protein genes in most strains. These data suggest the possible introduction and spread of international epidemic clones into Asian countries and the increasing problems of pneumococcal drug resistance in Asian countries for the first time.

Aminoacyltransferases↗
PubMed1998

Genetic and functional analysis of the styrene catabolic cluster of Pseudomonas sp. strain Y2.

The chromosomal region of Pseudomonas sp. strain Y2 involved in the conversion of styrene to phenylacetate (upper catabolic pathway) has been cloned and sequenced. Four catabolic genes, styABCD, and two regulatory genes, stySR, were identified. This gene cluster when transferred to Escherichia coli W confers to this phenylacetate-degrading host the ability to grow on styrene as the sole carbon and energy source. Genes styABCD are homologous to those encoding the styrene upper catabolic pathway in Pseudomonas fluorescens ST. Northern blot analyses have confirmed that genes styABCD constitute a transcription unit. The transcription start site of the sty operon was mapped 33 nucleotides upstream of the styA translational start codon. The styS and styR genes, which form an independent transcriptional unit, are located upstream of the styABCD operon, and their gene products show high similarity to members of the superfamily of two-component signal transduction systems. The styS gene product is homologous to histidine kinase proteins, whereas the styR gene product exhibits similarity at its N-terminal domain with cluster 1 of receiver modules and at its C terminus with the LuxR/FixJ family 3 of DNA-binding domains. Expression of the catabolic operon decreased significantly in the absence of the stySR genes and was restored when the stySR genes were provided in trans in the presence of styrene, suggesting that the stySR system behaves as a styrene-inducible positive regulator of the styABCD operon. Finally, a gene encoding a phenylacetyl-coenzyme A ligase that catalyzes the first step in the phenylacetate catabolism (styrene lower catabolic pathway) has been identified upstream of the styS gene. This activity was found to be induced in Pseudomonas sp. strain Y2 cells grown on styrene but not present in cells grown on glycerol. These results strongly suggest that the genes responsible for the complete mineralization of styrene are clustered in the chromosome of Pseudomonas sp. strain Y2.

Amino Acid Sequence↗
PubMed1998

[The ear of a boxer from Canary islands].

The canary fight is a sport with traditional character deeply-rooted in Spain. The pinna rubbing by bodies contact in hand-to-hand combat produce a typical deformity. We present this pathology not only due to its specific pathogenesis but also as part of the cultural patrimony of Canary Islands (Fortunate Islands).

Adult↗
PubMed1996

The pattern of tissue damage in occupational trauma.

OBJECTIVE: To study the pattern of tissue damage in occupational hand injuries. SETTING: Trauma and Orthopaedic Unit of the General Hospital, Colombo. PATIENTS: 190 patients with occupational hand injuries submitted to surgery by me were studied prospectively. The incidence of compound and simple fractures and dislocations, digital amputations, tendon injuries and skin loss were studied. The individual bones and tendons affected, the level of digital amputations and the involvement of individual fingers were recorded. RESULTS: Compound fractures accounted for 42.1% of injuries and in 56.4% the distal phalanx was involved. Finger tendons were affected in 66.6%. The highest incidence of compound fractures (30.6%), amputations (41.1%) and skin and subcutaneous tissue loss (28.5%) was seen in the index finger. CONCLUSIONS: 1. Compound fractures and digital amputations were the main injuries. 2. Distal phalanx is more frequently affected in compound fractures. 3. Among the amputations loss of finger tip is the commonest. 4. Flexor tendons were more injured than the extensor tendons. 5. Index finger is the most frequently injured digit.

Accidents, Occupational↗
PubMed1996

Primary drug resistant tuberculosis in the Central Chest Clinic, Colombo.

OBJECTIVE: To determine the drug sensitivity of Mycobacterium tuberculosis strains isolated from pretreatment (primary) cases of pulmonary tuberculosis. DESIGN: A descriptive study. SETTING: The Central Chest Clinic, Colombo. PATIENTS: 103 patients with pulmonary tuberculosis who have not taken anti-tuberculosis drugs previously. MEASUREMENTS: Antibiotic sensitivity pattern of M tuberculosis isolates for isoniazid (INAH), ethambutol (EMB), rifampicin (RMP) and streptomycin (SM) tested in drug incorporated Lowenstein Jenson (LJ) medium using resistance ratio method. RESULTS: 15.5% isolates of M tuberculosis were resistant to at least one drug. Resistance to a single drug was found to be most prevalent (69%) among the resistant isolates and among these INAH resistance was most prevalent followed by streptomycin. None of the isolates were resistant to all four drugs. Resistance rates to individual drugs were INAH 9.7%. SM 6.7% EMB 2.9% and RMP 2.9%. CONCLUSIONS: Since the introduction of RMP and EMB in the treatment regimens from mid-1970s the incidence of tuberculosis and rate of primary drug resistance to anti-tuberculosis drugs has not changed significantly (p > 0.05) when compared with the results of studies conducted previously (2, 3). However, it is recommended that regular surveillance of drug sensitivity pattern should be maintained to determine alternate drug regimes and to detect the spread of resistant strains in the community.

Adult↗
PubMed1995

Anatomy of the origin of the deep femoral artery.

OBJECTIVE: To study the variability in the level of origin of the deep femoral artery in relation to the different patterns of origin of the femoral circumflex arteries. DESIGN: 124 femoral triangles obtained from cadavers were dissected. The origins of the circumflex femoral arteries were classified into two groups. In group A medial and lateral circumflex arteries arose from the deep femoral artery. In group B either one or both femoral circumflex arteries arose from the common femoral artery. The distance of origin of the deep femoral artery from the mid point of the inguinal ligament was measured in both groups and compared. SETTING: Department of Anatomy, Faculty of Medicine, Colombo. RESULTS: A statistically significant difference was noted in the two groups regarding the level of origin of the deep femoral artery. CONCLUSION: There is a distal migration of the level of origin of the deep femoral artery when either one or both circumflex femoral arteries arose from the common femoral artery.

Anthropometry↗
PubMed1994

PCR based detection of Mycobacterium tuberculosis: effect of sample preparation.

Tests based on the polymerase chain reaction (PCR) for the detection of the Mycobacterium tuberculosis complex in clinical samples have a lower sensitivity when compared to culture. This has been attributed to the presence of inhibitors to Taq polymerase and/or suboptimal DNA extraction procedures. We tested different methods of processing smear negative culture positive sputum (n = 52) using different detergents, including nonidet P-40 (NP-40), sodium dodecyl sulphate (SDS), tween 20, triton X 100 and N-lauryl sarcosine. The detergents were used in combination with lysozyme and proteinase K enzymes. NP-40 was significantly better than SDS, tween 20 and N lauryl sarcosine (p < 0.05). When NP-40 was used as the detergent, 42 out of 52 specimens gave positive results with the standard amplification protocol which amplifies a 245 bp sequence of the insertion element IS 986. The 10 specimens that were negative were further diluted ten fold and/or eluted in sephadex G-50 columns before standard DNA amplification. A further 8 specimens then became positive. Elution in sephadex G-50 was better than ten fold dilution in processing of samples. The two negative samples had very low colony counts (n < 5). The study demonstrates that the sensitivity of the PCR is dependent on the sample preparation technique and the amount of target sequence available for amplification.

DNA, Bacterial↗
PubMed1994

Econazole and clotrimazole in the treatment of vaginal candidiasis: a double blind comparative study.

OBJECTIVES: To compare the efficacy of treatment with econazole and clotrimazole in patients with vaginal candidiasis. DESIGN: A double blind study. Patients with vaginal candidiasis were randomly treated with vaginal depot preparations of econazole and clotrimazole. Efficacy after treatment by reduction of symptoms, a gynaecological examination and microbiological analysis of vaginal fluid. Adverse reactions were noted. SETTING: University gynaecological clinic at the de Soysa Hospital for Women, Colombo. PATIENTS: 102 patients microbiologically confirmed as having vaginal candidiasis. RESULTS: Two weeks after econazole treatment 19% still complained of a discharge and 7.5% had pruritus. The respective values for clotrimazole were 18% and 12%. The finding on gynaecological examination generally supported the reduction of symptoms. Microbiological assessment showed that 90.5% in the econazole group and 96% in the clotrimazole group became culture negative at two weeks after treatment. Adverse effects were similar in incidence and number for both treatment groups. Econazole was less acceptable to patients than clotrimazole. CONCLUSIONS: Econazole and clotrimazole are of equal efficacy for treatment of vaginal candidiasis. Econazole was less acceptable to patients.

Adolescent↗