Mortality and AIDS-defining events among young people following transition from paediatric to adult HIV care in the UK.

OBJECTIVES: To investigate risk of AIDS and mortality after transition from paediatric to adult care in a UK cohort of young people with perinatally acquired HIV. METHODS: Records of people aged ≥ 13 years on 31 December 2015 in the UK paediatric HIV cohort (Collaborative HIV Paediatric Study) were linked to those of adults in the UK Collaborative HIV Cohort (CHIC) cohort. We calculated time from transition to a new AIDS event/death, with follow-up censored at the last visit or 31 December 2015, whichever was the earliest. Cumulative incidence of and risk factors for AIDS/mortality were assessed using Kaplan-Meier and Cox regression. RESULTS: At the final paediatric visit, the 474 participants [51% female, 80% black, 60% born outside the UK, median (interquartile range) age at antiretroviral therapy (ART) initiation = 9 (5-13) years] had a median age of 18 (17-19) years and CD4 count of 471 (280-663) cell/µL; 89% were prescribed ART and 60% overall had a viral load ≤ 400 copies/mL. Over median follow-up in adult care of 3 (2-6) years, 35 (8%) experienced a new AIDS event (n = 25) or death (n = 14) (incidence = 1.8/100 person-years). In multivariable analyses, lower CD4 count at the last paediatric visit [adjusted hazard ratio = 0.8 (95% confidence interval: 0.7-1.0)/100 cells/µL increment] and AIDS diagnosis in paediatric care [2.7 (1.4-5.5)] were associated with a new AIDS event/mortality in adult care. CONCLUSIONS: Young people with perinatally acquired HIV transitioning to adult care with markers of disease progression in paediatric care experienced poorer outcomes in adult care. Increased investment in multidisciplinary specialized services is required to support this population at high risk of morbidity and mortality.

Maxillary lateral incisor with two roots.

Variations in root canal morphology can lead to complications in endodontic treatment. A case of a maxillary lateral incisor with two roots is reported.

Removal of contaminant nucleic acids by nitrocellulose filtration during pharmaceutical-grade plasmid DNA processing.

Pharmaceutical-grade plasmid DNA for use in vaccines and gene therapy requires the development of reproducible and scaleable downstream processes. Shearing of chromosomal DNA at the commencement of the purification results in fragments that are difficult to separate from supercoiled plasmid DNA. Regulatory standards will probably require that the level of chromosomal DNA contamination is kept below 0.01 mg mg(-1) plasmid DNA. This work reports the use of nitrocellulose membranes to decrease chromosomal DNA contamination in plasmid DNA preparations derived from a 450-l bioreactor. Clarified lysates, resuspended PEG precipitates and anion exchange chromatography elutes were filtered through nitrocellulose. In all the cases, chromosomal DNA was selectively retained by the membrane while most supercoiled plasmid DNA was recovered in the filtrate. Contamination levels dropped from over 27% to below 1% as measured by Southern analysis. Under ionic strength conditions equal to or above 1.5 M NaCl, a fraction of the contaminant RNA was also retained by the nitrocellulose membrane.

Separation and purification of oligonucleotides using a new bonded-phase packing material.

We describe a new bonded-phase packing material, based upon surface-stabilised microparticulate silica, suitable for the rapid separation and purification of oligonucleotides. Columns packed with this material were demonstrated to give rapid separations of individual oligonucleotide species of up to 44 base units with high purity; agarose gel electrophoresis showed that the products were essentially single bands, with only trace quantities of the (n-1)-mer present. Baseline resolution of the desired oligomer from (n +/- 1)-mer was achieved under preparative loading conditions, where up to 200-300 micrograms of oligonucleotide could be separated. The separation was essentially independent of structure or sequence of the oligonucleotides. The retention mechanism of the oligonucleotides was investigated, and the results used to determine the optimum column configuration and separation conditions.