A spatial and temporal analysis of paediatric central nervous system infections from 2005 to 2015 in Ho Chi Minh City, Vietnam.

Central nervous system infections (CNSI) are a leading cause of death and long-term disability in children. Using ICD-10 data from 2005 to 2015 from three central hospitals in Ho Chi Minh City (HCMC), Vietnam, we exploited generalized additive mixed models (GAMM) to examine the spatial-temporal distribution and spatial and climatic risk factors of paediatric CNSI, excluding tuberculous meningitis, in this setting. From 2005 to 2015, there were 9469 cases of paediatric CNSI; 33% were ⩽1 year old at admission and were mainly diagnosed with presumed bacterial CNSI (BI) (79%), the remainder were >1 year old and mainly diagnosed with presumed non-bacterial CNSI (non-BI) (59%). The urban districts of HCMC in proximity to the hospitals as well as some outer districts had the highest incidences of BI and non-BI; BI incidence was higher in the dry season. Monthly BI incidence exhibited a significant decreasing trend over the study. Both BI and non-BI were significantly associated with lags in monthly average temperature, rainfall, and river water level. Our findings add new insights into this important group of infections in Vietnam, and highlight where resources for the prevention and control of paediatric CNSI should be allocated.

Single dose artemisinin-mefloquine versus mefloquine alone for uncomplicated falciparum malaria.

The efficacy of the combination of a single oral dose of 500 mg artemisinin with a single 500 mg oral dose of mefloquine (AM) in the treatment of uncomplicated falciparum malaria was compared to mefloquine therapy alone (M) in a double-'blind' randomized study in an endemic area in the south of Viet Nam where single low dose treatment was employed and where mefloquine had been recently introduced. 231 patients, 117 AM and 114 M, were studied. Failure of therapy occurred in 1 AM patient and in 3 M patients. The radical cure rate was 84% for the AM regimen and 65% for the M regimen (P = 0.002). Recrudescence (including an unknown percentage of reinfections) occurred in 15% of AM patients and in 30% of M patients (P = 0.01). The mean parasite clearance time was 40 h (SD = 16) for AM and 60 h (SD = 27) for the M regimen (P = 0.0001). No effect of artemisinin was noted on gametocytes present on admission, but new gametocytes developed less frequently in the AM group. The addition of a single dose of 500 mg artemisinin to 500 mg mefloquine increased the efficacy and reduced the rate of recrudescence, but this regimen was not adequate and, for short course regimens, more doses of artemisinin as well as higher, doses of mefloquine should be studied.

Genomic 5-methylcytosine determination by 32P-postlabeling analysis.

A simple and sensitive method for the quantitation of 5-methyldeoxycytidine in DNA has been developed by the adaptation of the Randerath 32P-postlabeling technique. Nucleic acids were digested to 3'-monophosphate nucleotides, which were converted to 32P-labeled 3',5'-bisphosphate nucleotides, the 3'-phosphate was cleaved by the action of nuclease P1, and the resultant 5'-[32P]-monophosphate nucleotides were separated by two-dimensional thin-layer chromatography. Less than 1 microgram of DNA was required for the precise quantitation of 5-methyldeoxycytidine content to a detectable limit of 0.01% of the total cytidine residues methylated. The genomic 5-methyldeoxycytidine content may thus be quantitated in tissue samples, small or selective cell populations, senescing or terminally differentiating cells, or DNA from any source. We report here, for the first time, the genomic 5-methyldeoxycytidine content of normal human bronchial epithelial and normal human pulmonary mesothelial cells. The chromatographic separation of all of the normal and some of the rare monophosphate deoxyribonucleotides and ribonucleotides has been characterized. Thus, 5-bromodeoxyuridine and the RNA contamination of DNA or the DNA contamination of RNA can also be quantitated during the same analysis.