Airborne Pseudomonas species in Healthcare Facilities in a Tropical Setting.

BACKGROUND AND OBJECTIVES: Pseudomonas species are nosocomial pathogens that are capable of colonising moist surfaces. Little is known whether they get airborne. The study was undertaken to 1) characterise Gram-negative bacteria in indoor air of different hospitals; 2) characterise Pseudomonas sp. by phenotypic and genotypic methods; 3) determine homology of study environmental Pseudomonas isolates and correlate with established pathogenic strains' sequences. METHODS: Samples were collected (duplicates) at the time of peak activity, by exposing media-containing plates (blood agar and MacConkey agar) for 30 minutes. Plates were incubated aerobically at 37°C for 24-48 h. Microorganisms were identified by standard microbiological procedures. Polymerase chain reaction targeting Pseudomonas specific 16S-rDNA was performed to obtain 618 bp amplicons. Representative strains were sequenced and compared with established sequences of pathogenic Pseudomonas strains from existing database for evolutionary details. RESULTS: A total of six hospitals comprising 13 wards, 7 intensive care units (ICUs) and 8 operating rooms (ORs) were sampled over one-year period. A variety of Gram-negative bacilli were isolated, of which Pseudomonas sp. was predominant. Indoor air of 10 wards (77%), 5 ICUs (71%), 4 ORs (50%) harboured Pseudomonas. Similar strains of Pseudomonas stutzeri were isolated from indoor air of different hospitals. Phylogenetic analysis showed these environmental strains to be closely related to the pathogenic Pseudomonas stutzeri strain from the GenBank database. CONCLUSIONS: Isolation of airborne Pseudomonas stutzeri from different hospitals suggests a possible new reservoir in the hospital environment, indicating the need for appropriate engineering control measures to contain the spread of these nosocomial agents.

Molecular characterization of Chikungunya virus during an outbreak in South India.

INTRODUCTION: Re-emergence of Chikungunya is a major public health problem in the southern states of India. OBJECTIVES: This study was undertaken to investigate an outbreak of Chikungunya, in June-August 2008 using PCR and determine the prevalent genotypes of Chikungunya virus (CHIKV) associated with the outbreak. MATERIALS AND METHODS: Samples of blood were collected (in heparinized vacutainer tubes) from suspected patients of CHIKV infection from both Government Taluk Hospital in Kerala and a tertiary care hospital in Chennai, Tamil Nadu. A one-step RT-PCR was carried out on a block thermo-cycler targeting the E2 gene that codes for the viral envelope protein. The amplicons were verified for 305 bp size by standard agarose gel electrophoresis. The PCR products were purified, sequenced, and compared with other CHIKV strains reported from different geographical regions. A phylogenetic tree was constructed using MEGA 4. RESULTS: Altogether 118 samples were collected from patients who presented with sudden onset of fever and/or joint pain, myalgia, and headache. CHIKV infection was confirmed by RT-PCR in 14 patients and all these cases were from Kerala. The positivity correlated with the early stage of the disease as all these patients had fever of less than seven days duration. The study isolates have been allotted the GenBank accession nos. GQ272368-GQ272381. Phylogenetic analysis of recent CHIKV isolates by partial sequencing of E2 region shows that isolates are closely related to strains from neighboring states and the African type. CONCLUSION: RT-PCR is a useful technique for the early detection of CHIKV infection during outbreaks. Molecular characterization of the strains indicates that majority of the strains have originated from the Central/East African strains of CHIKV.

Glucose metabolism and larger molecule removal in long-term high efficiency hemofiltration.

High efficiency hemofiltration (HF) was carried out for 9 months in 6 patients on hemodialysis (HD). Comparative studies on carbohydrate metabolism and 500- to 1,500-dalton serum solute concentrations were performed during HD and HF. After 5 months of HF, intravenous glucose tolerance tests showed an improved peripheral glucose utilization, with unchanged insulin secretion. Larger solute concentrations, measured by gel chromatography, simultaneously dropped in serum suggesting that HF removes some toxic substances that inhibit peripheral insulin action. After 9 months of HF, an unexpected increase in the larger solute concentration coincided with an impaired glucose tolerance, stressing the probable toxic rule of such solutes. Changes in other glucoregulatory hormone secretions were not unequivocal. On account of the later increase in 500- to 1,500-dalton solute concentrations, HF failed to prevent larger toxic molecules accumulating in uremic sera.

Time-dependent increase of glomerular filtration rate after oral protein load: evidence for diurnal variations in renal response.

Seven healthy male volunteers were studied to test the effect of timing of an oral protein load on renal function. Creatinine clearance (Ccr) was measured during the 4-h period after administration of 72 g of protein in the form of cooked red meat at 1200 hours (lunch protein load, PL) and at 2000 hours (supper PL) the next evening. A low-protein meal in the form of vegetables was given as a control load at 2000 hours on the first day (supper control load, CL) and at 1200 hours on the second day (lunch CL). The 12-h night-time Ccr at fasting was used as the baseline reference value. After the lunch PL, Ccr (mean 127 +/- 6.8 ml/min) was 45% (p less than 0.001) higher than the baseline value (mean 87.9 +/- 5.3 ml/min) and 33% (p less than 0.001) higher than lunch CL (mean 95.8 +/- 5.6 ml/min). After the supper PL, Ccr (mean 106.2 +/- 8.7 ml/min) was 20% (p less than 0.01) higher than the baseline value and 15% (p less than 0.01) higher than the supper CL (mean 93.0 +/- 9.3 ml/min). The differences between baseline and control load values were not statistically significant. In all seven patients, the protein load induced a maximum Ccr value at lunchtime, and Ccr after the lunch PL was 22% higher than Ccr after the supper PL (p less than 0.01). We conclude that in healthy individuals, the Ccr after an oral protein load is correlated to the hour of the day when the study is performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Circadian rhythm of proteinuria in normal subjects but not in patients with glomerulonephritis.

The existence of circadian variations in the urinary excretion of total protein, albumin and creatinine was investigated in subjects with normal and impaired renal function. All individuals were kept at bedrest for 24 hours. Eight consecutive urine specimens were collected every 3 hours and examined. In normal subjects the urinary total protein, albumin and creatinine excretion showed a significant increase during the 12 daytime hours compared with the night-time. The diurnal variations with peak occurrence at 13.26 h (range 09.58-16.43 h) for total protein, at 12.37 h (range 10.33-15.18 h) for albumin, at 16.33 h (range 13.22-19.24 h) for creatinine are temporally related to the ingestion of meat. In patients, by contrast, total protein, albumin and creatinine excretion in the urine were not modified significantly throughout the 24 hours period. Thus, impaired renal function is associated with the loss of the physiological circadian rhythm.