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Biomedical subjects

J Whitworth

Publications and source records attributed to J Whitworth.

At least 55 records · Page 3Linked to original sources
PubMed1998

Cross-clade recognition of p55 by cytotoxic T lymphocytes in HIV-1 infection.

OBJECTIVES: To evaluate cross-clade recognition of p55 antigen by cytotoxic T lymphocytes (CTL) in persons infected with diverse clades of HIV-1; to facilitate the development of a CTL-inducing vaccine to prevent transmission of multiple clades of HIV-1. DESIGN: Experiments were designed to evaluate whether persons in Uganda and the United Kingdom, infected with diverse clades of HIV-1, have CTL capable of recognizing and killing autologous target cells infected with recombinant vaccinia viruses (rVV) expressing the Gag protein from A, B, C and D clade HIV-1. The extent of cross-reactivity within such individuals, each infected with characterized virus, might reflect the type of cross-reactive immune response inducible by a monovalent vaccine. METHODS: Asymptomatic HIV-positive individuals were fully tissue-typed by ARMS (amplification of refractory mutation system) polymerase chain reaction. rVV expressing the Gag protein from identified A, B, C and D viruses were prepared. CTL were cultured and tested for cytolytic activity on autologous rVV-infected or peptide-pulsed B cells. RESULTS: Ugandan patients had inducible CTL responses recognizing A, B, C and D clade HIV-1 Gag. The majority of UK patients had inducible CTL responses that recognized two or more clades. No patient showed any HIV-2 cross-reactivity. Cross-reactive responses were characterized in three Ugandan patients. CONCLUSIONS: Most patients tested mounted cross-reactive CTL responses that recognized Gag proteins from clades of HIV-1 other than those with which they were infected.

Amino Acid Sequence↗
PubMed1998

Early manifestations (pre-AIDS) of HIV-1 infection in Uganda.

OBJECTIVES: To describe the early manifestations of HIV-1 infection before the development of AIDS, in a rural Ugandan population. METHODS: Three monthly follow-up of HIV-1-infected and uninfected participants in an HIV-1 natural history cohort from the start of the cohort in 1990 to the end of 1996. RESULTS: A total of 107 persons with prevalent infection and 104 persons with incident infection were enrolled. Eighty (75%) prevalent and 89 (86%) incident individuals were asymptomatic on enrollment. Of the 91 persons with incident infection seen within 2 years of their estimated date of seroconversion, 51% [95% confidence interval (CI), 40-61] were still asymptomatic 2 years after seroconversion. At 4 and 5 years after seroconversion, only 26% (95% CI, 17-36) and 11% (95% CI, 4-22), respectively, remained asymptomatic. A total of 89 participants entered World Health Organization (WHO) stage 2, and their main stage-defining conditions were weight loss <10% (and > 5%) and minor mucocutaneous manifestations. The median CD4 lymphocyte count for participants entering WHO stage 2 was 516 x 10(6) cells/l (interquartile range, 360-884 x 10(6)/l). A total of 94 participants entered WHO stage 3 and the main reasons were weight loss >10%, unexplained chronic diarrhoea, fever for more than 1 month, and severe bacterial infection. The median CD4 lymphocyte count for participants entering WHO stage 3 was 428 x 10(6) cells/l (interquartile range, 276-736 x 10(6)/l). The rates of all conditions reported under the WHO staging system were significantly more frequent in HIV-positive persons than HIV-negative controls with the exception of fever for more than 1 month and oral hairy leukoplakia (which was seen in only three individuals). CONCLUSION: These are the first data from a non-selected African population describing the early manifestations of HIV infection. The main early manifestations were weight loss, minor mucocutaneous features, chronic diarrhoea, chronic fever and severe bacterial infections. The apparent rapid development of HIV-related signs and symptoms is probably indicative of the high background level of these conditions in our study area, as reflected by the rates of these conditions in the HIV-negative controls.

Adult↗
PubMed1998

The management of thermomechanically compacted gutta percha extrusion in the inferior dental canal.

Endodontic material inadvertently forced into the inferior dental canal during root-canal therapy can cause damage to the underlying nerve. The effect of toxic filling materials on nervous tissues has been well publicised, however, the thermal and pressure changes produced by chemically bland materials has not been adequately highlighted. In the case reported, thermoplasticised gutta percha was inadvertently introduced into the canal during endodontic treatment of a lower molar. Factors affecting the outcome are discussed and guidelines are presented for the management of such a case with reference to surgery against observation.

Adult↗
PubMed1998

Molecular epidemiological analysis of HIV in sexual networks in Uganda.

OBJECTIVE: To investigate the suitability of HIV sequence analysis, based on the p17 region of the gag gene, to characterize the sexual networks in and around a trading town in south-west Uganda. METHODS: Blood samples were obtained from 54 HIV-seropositive members of three distinct sexual networks and phylogenetic analysis carried out on proviral DNA sequences obtained from the p17 region of gag from 53 individuals. RESULTS: Despite documented evidence of very little sexual mixing between residents of the trading town, fishing village and surrounding rural area, there was no evidence of clustering of sequences associated with place of residence. More strikingly, known sexual partners failed to show significantly related sequences, and the two pairs of sequences that did show significant similarity came from individuals who had no known social or sexual contact. CONCLUSIONS: Sequence analyses such as those described here have proved effective in confirming or identifying epidemiological links not only following single transmission events but also within risk groups. However, the results from Uganda contrast markedly with those from Europe and the United States. The length of time that the community has been infected, the number of occasions when the virus has been introduced and the high degree of partner change may contribute to the lack of supportive evidence for sociological studies of sexual networks in Uganda.

DNA, Viral↗
PubMed1998

Causes of death in a rural, population-based human immunodeficiency virus type 1 (HIV-1) natural history cohort in Uganda.

BACKGROUND: While human immunodeficiency virus (HIV)-related causes of death have been well documented in developed countries, in Africa data are scanty and mainly based on autopsy studies from city hospitals which are highly selective and may not represent causes of HIV-associated deaths in the general population. This study, from a rural population, describes the causes of death in HIV-positive people and their HIV-negative controls. METHODS: A natural history cohort comprising HIV-1 infected participants and HIV-negative controls was established in rural Uganda in 1990. Causes of death were determined by reviewing the premorbid clinical and laboratory findings and from information obtained from relatives. Blindness to the deceased's HIV serostatus was maintained throughout. RESULTS: In all, 78 deaths occurred over a 6-year period: 63 deaths occurred in the HIV-positive cases (53 prevalent and 10 incident cases) and 15 deaths in the HIV-negative controls. Of the prevalent cases, 56%, and 9% the incident cases enrolled died, compared with 7% of the HIV-negative controls. Of the 55 HIV-positive cases with sufficient data to establish cause of death, 52 (95%) were assessed as having HIV-associated deaths and 48 (87%) died in WHO stage 4 (AIDS). The main causes of death were wasting syndrome (31%), chronic diarrhoea (22%), cryptococcal meningitis (13%) and chest infection (11%). CONCLUSIONS: Our results represent an unbiased selection of deaths in a rural area. The HIV-positive cases have high death rates and die of HIV-related pathologies. The main causes of death reflect the WHO clinical case definition of AIDS. Cryptococcal meningitis is also a common cause of death in this population.

Adult↗
PubMed1998

Complementary therapy and cardiac surgery.

Mind-body techniques and complementary care may assist people who are undergoing surgery and those recovering from cardiac surgery to cope with the event, the process of recovery, and accompanying lifestyle changes. These approaches can provide cardiac patients with nonpharmacologic tools that may prevent further coronary artery disease and the development of dysrhythmias. The Complementary Care Center at Columbia-Presbyterian Medical Center was developed to clinically apply and research the use of nonallopathic, complementary modalities with patients receiving care at the medical center, including those undergoing cardiac surgery.

Adaptation, Psychological↗
PubMed1997

Mortality associated with HIV-1 infection over five years in a rural Ugandan population: cohort study.

OBJECTIVE: To assess the impact of HIV-1 infection on mortality over five years in a rural Ugandan population. DESIGN: Longitudinal cohort study followed up annually by a house to house census and medical survey. SETTING: Rural population in south west Uganda. SUBJECTS: About 10,000 people from 15 villages who were enrolled in 1989-90 or later. MAIN OUTCOME MEASURES: Number of deaths from all causes, death rates, mortality fraction attributable to HIV-1 infection. RESULTS: Of 9777 people resident in the study area in 1989-90, 8833 (90%) had an unambiguous result on testing for HIV-1 antibody; throughout the period of follow up adult seroprevalence was about 8%. During 35,083 person years of follow up, 459 deaths occurred, 273 in seronegative subjects and 186 in seropositive subjects, corresponding to standardised death rates of 8.1 and 129.3 per 1000 person years. Standardised death rates for adults were 10.4 (95% confidence interval 9.0 to 11.8) and 114.0 (93.2 to 134.8) per 1000 person years respectively. The mortality fraction attributable to HIV-1 infection was 41% for adults and was in excess of 70% for men aged 25-44 and women aged 20-44 years. Median survival from time of enrollment was less than three years in subjects aged 55 years or more who were infected with HIV-1. Life expectancy from birth in the total population resident at any time was estimated to be 42.5 years (41.4 years in men; 43.5 years in women), which compares with 58.3 years (56.5 years in men; 60.5 years in women) in people known to be seronegative. CONCLUSIONS: These data confirm that in a rural African population HIV-1 infection is associated with high death rates and a substantial reduction in life expectancy.

Adolescent↗
PubMed1997

Sexual networks in Uganda: casual and commercial sex in a trading town.

A longitudinal study of the sexual behaviour of high-risk men and women living in a trading town on the trans-Africa highway showed that distinct sexual networks operated within the town. Forty-eight prostitutes kept daily records for 6 months of all their sexual contacts including the occupation and place of residence of each client and the price paid. Details of 4573 sexual contacts of the women were recorded. Three classes of women were identified: (1) 20 "high-class' women who charged a mean price of over US $4/- per contact. The majority of their clients were from large urban areas of Uganda (55%) or neighbouring countries (32%)-70% were truck-drivers or their mates; (2) 18 "low-class' women, charging an average of US $0.4 per contact, who were patronized predominantly by men resident in the town (71%) who were unskilled casual workers (58%); (3) 10 women fell into an intermediate category in terms of price and the residence of their clients. Thirty-eight male potential clients were recruited in low-cost bars where some of the women worked. They provided similar details of their daily sexual contacts. All were resident in the town and 22 had occupations which were classified as unskilled. Of the 1621 sexual contacts recorded by the men 25% were with new partners.

Adult↗
PubMed1997

Laser skin resurfacing with the Q-switched Nd:YAG laser.

BACKGROUND: Recent studies have shown that char-free pulsed carbon dioxide lasers are useful in the treatment of rhytids. Other infrared lasers have also been observed to induce changes in the skin. OBJECTIVE: In this pilot study, we evaluated the rhytid resurfacing capability of the Q-switched neodymium:yttrium-aluminum-garden (QS Nd:YAG) laser at 1064 nm as compared with char-free carbon dioxide lasers at 10,600 nm. METHODS: Three lasers were used in the study: The QS Nd:YAG laser, the SilkTouch carbon dioxide laser, and the UltraPulse carbon dioxide laser. Eleven subjects were treated in either the periorbital or perioral region with the QS Nd:YAG laser on one side of the face, and both of the char-free pulsed carbon dioxide lasers on the other side. The subjects were evaluated at posttreatment days 7, 30, 60, and 90 for improvement of rhytids, healing, pigmentary changes, and erythema. RESULTS: All 11 patients treated with the char-free carbon dioxide lasers improved. Nine of 11 patients treated with the QS Nd:YAG laser were improved. Healing (complete reepithelialization) was noted to occur 3-6 days earlier in sites treated with the QS Nd:YAG than in sites treated with char-free carbon dioxide lasers. Pigmentary changes were not observed in any treatment site. Erythema was observed at 1 month after treatment in all areas treated with the char-free carbon dioxide lasers, but only three patients treated with the QS Nd:YAG exhibited erythema. These were the same three QS Nd:YAG-treated patients whose clinical improvement was comparable with that of the char-free carbon dioxide lasers. CONCLUSION: The Q-switched Nd:YAG laser may play a role in the treatment of rhytids.

Dermatologic Surgical Procedures↗
PubMed1997

Randomised trials of STD treatment for HIV prevention: report of an international workshop. HIV/STD Trials Workshop Group.

Three community trials of the impact of STD treatment interventions on HIV incidence in rural populations have been completed or are in progress in Uganda and Tanzania. Investigators from these trials met for a joint technical workshop in Baltimore in May 1996. This report summarises the consensus of the workshop, with the aim of providing useful input to research on HIV intervention strategies. Issues discussed include: (i) the role of community randomised trials; (ii) strategies for STD management; (iii) epidemiological and statistical issues in the design and analysis of community randomised trials; (iv) diagnostic methods for STDs in population surveys; (v) treatment regimens for STDs in rural Africa; and (vi) ethical issues in community trials.

Community Health Services↗
PubMed1997

Sexual networks in Uganda: mixing patterns between a trading town, its rural hinterland and a nearby fishing village.

The study was based in south-west Uganda where significant differences in HIV prevalence have been found between urban and rural areas. Longitudinal data collected in a diary format was used to determine the extent to which high-risk men and women living in a truck stop/trading town had sexual contact with people from surrounding rural areas and a nearby fishing village. Study participants were 143 men, 75 of whom were resident in the town, 40 in a fishing village and 28 in rural areas, and 81 women, of whom 47 were resident in the town, 25 in the fishing village and 9 in a rural area. During 1687 man weeks the 143 men made 3149 trips and had 5189 sexual contacts. Ninety-two per cent of these sexual contacts occurred in the man's current place of residence and 21% were with a new partner. The 81 women participated for 1280 women weeks during which they recorded 6378 sexual contacts. Women who lived in the fishing village and the rural area had around 90% of their contacts with local men while those who lived in the town fell into 3 categories: women who charged a relatively high price for commercial sex had only 11% of contacts with men living in the town, while those who charged a tenth of the price had 71% of contacts with town men. The small number of women who fell into an intermediate category, in terms of price, had sexual contact with a wide variety of men. These findings show that there is little scope for HIV infection to spread between different residential or occupational groups. This may help to explain how large differences in HIV seropositivity between neighbouring localities can be maintained for long periods, despite considerable social and economic mixing between groups and high levels of sexual partner change within groups.

Adolescent↗
PubMed1997

Sexual behaviour in a fishing community on Lake Victoria, Uganda.

This study describes the sexual behaviour of men and women in a fishing village on the shores of Lake Victoria in southwest Uganda. The village is near a well known trading town-truckstop on the main trans-Africa highway with a high recorded prevalence of HIV infection. Data were obtained on the daily travel and sexual activities of 26 women and 54 men with particular attention paid to the rate of partner change and the proportion of sexual contacts with people outside the village. During a total of 587 person weeks the men made 1086 trips, mostly returning home the same day. They had a total of 1226 sexual contacts, most of which occurred either in their own village (83%) or a neighbouring fishing village (11%); 17 per cent of sexual contacts were with new partners. Fifteen of the women described themselves as married; 42 per cent of their sexual contacts were casual, paying partners. Of the eleven women who were single, between 80 and 100 per cent of contacts were with paying partners. Most of the women's partners were resident in the village. These data show a very high rate of sexual mixing within the village. Such communities should be targeted in future STD control programs.

Adolescent↗