Search PubMed⌕ Search

Biomedical subjects

D J Jeffries

Publications and source records attributed to D J Jeffries.

118 records · Page 7Linked to original sources
PubMed1973

Australia (hepatitis-associated) antigen in patients attending a venereal disease clinic.

A total of 1,650 patients attending the venereal disease department at St. Mary's Hospital, London, have been tested for Australia antigen. Twenty-three positive results were obtained, or 1.39%, which is more than 10 times the rate noted by others in blood donor populations in the U.K. and U.S.A. The positive rates among female patients and European male heterosexual patients were 0.36% and 0.19% respectively. High rates were obtained for homosexual patients (3.8%) and non-European heterosexual patients (3.1%). The reasons for the higher rates found in these groups merit further study.

Adult↗
PubMedDate not supplied

Induction of neutralizing antibody and T-cell responses to varicella-zoster virus (VZV) using Ty-virus-like particles carrying fragments of glycoprotein E (gE).

During infection with Varicella-zoster virus (VZV), the envelope proteins are highly immunogenic and glycoprotein E (gE) is one of the most abundant and antigenic. We have previously identified the immunodominant regions of gE and mapped the B-cell epitopes. In this study, we have evaluated the immunogenicity of recombinant hybrid Ty-virus-like particles (VLPs) carrying amino acids (1-134) or (101-161) of gE which contain the immunodominant sequences. VZV-specific antibodies were detected by ELISA in sera from mice and guinea pigs immunized with either gE(1-134)-VLPs or gE (101-161)-VLPs. The dominant B-cell epitopes, mapped by pepscan analysis of the sera, were found in peptides spanning amino acids 41-60, 56-75, 101-120, 116-135, 131-150 and 141-161. These sera also showed neutralizing activity against VZV in vitro. Epitopes recognized by neutralizing MAbs were mapped to both gE sequences (3B3 MAb recognizing amino acids 141-161 and IFB9 MAb recognizing amino acids 71-90). Lymphocyte proliferative responses to VZV were detected in four different mouse strains immunized with either gE(1-134)-VLPs or gE(101-134)-VLPs in alum. All mouse strains immunized with gE(1-134)-VLPs recognized epitopes in amino acids 11-30 and 71-90 and all those immunized with gE(101-161)-VLPs recognized epitopes in amino acids 91-110 and 106-125. These results indicate that VLPs carrying these gE sequences can prime potent humoral and cellular anti-VZV responses in small animals and warrant further investigation as potential vaccine candidates against varicella-zoster infections.

Amino Acid Sequence↗
PubMedDate not supplied

Eight year prospective study of HIV infection in a cohort of homosexual men--clinical progression, immunological and virological markers.

Three hundred and fourteen homosexual/bisexual men at risk for human immunodeficiency virus (HIV) infection (170 seroprevalent HIV-positive, 144 seronegative) were prospectively studied over 8 years to assess rates of HIV infection and disease progression, in conjunction with cellular and HIV serological markers. In HIV-positive subjects, CD4+ lymphocyte counts rose strikingly during the period surrounding seroconversion, then fell progressively over the intervening period to a mean level of 300 cells/mm3 when AIDS developed. Changes in CD8+ lymphocyte counts were less consistent. The trend for HIV serological markers over the study period was of progressive decline in the proportion of subjects with anti-p24 antibody, associated with an increase in the proportion of subjects with detectable HIV antigenaemia. However, only 45% of subjects tested had lost anti-p24 antibody by the time of AIDS diagnosis, and HIV antigen was detectable up to 4 years before this. Different HIV serological patterns were also observed in subjects presenting either with Kaposi's sarcoma or opportunist infections. Our data support the continued use of cellular and virological markers in the evaluation of HIV disease; however, the variability observed in this study highlights their limited ability in predicting specific clinical events. Care should therefore be taken to encompass both clinical and laboratory information in the medical assessment of the HIV-infected individual.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Trends in sexual behaviour in a cohort of homosexual men: a 7 year prospective study.

A cohort of homosexual men at risk for human immunodeficiency virus (HIV) infection were studied prospectively over a 7-year period (1982/88) to assess trends in sexual behaviour and amyl nitrite intake. During the period, there were dramatic declines in the proportion of HIV seropositive and seronegative subjects reporting multiple casual partners for anal intercourse, unprotected anal intercourse and recreational use of amyl nitrite. Reported rates of orogenital intercourse remained the same during the period, whilst the total number of seroconversions fell from 17 for the period 1982-84 to 8 for 1985-88. High-risk sexual and related social behaviour among homosexual men, as assessed by patterns of anal intercourse behaviour and nitrite intake, changed over the 7-year period, with the greatest changes apparent before the widespread availability of HIV antibody testing and public education campaigns. This highlights the effectiveness of peer-group and community-based programmes in modifying the sexual behaviour of their members.

Adolescent↗
PubMedDate not supplied

The activity of candidate virucidal agents, low pH and genital secretions against HIV-1 in vitro.

The effect of low pH, normally present in the female genital tract, on HIV viability was examined. HIV is more acid stable than previously reported with no substantial reduction in infectivity occurring until pH levels are reduced below 4.5. The virucidal activity of 3 topical spermicides and chlorhexidine was assessed in vitro using previously established and newly modified assay systems. None of the agents tested had a selectivity index (SI) greater than 5.2. Semen and cervical secretions were assessed for their ability to inhibit HIV-1. While no virucidal effect was found in the latter, seminal fluid was found to have significant activity against HIV-1 and a SI of approximately 50.

Administration, Intravaginal↗
PubMedDate not supplied

Effect of furosemide upon morphology of hair bundles in guinea pig cochlear hair cells.

Furosemide was administered by intraperitoneal injection and intracochlear perfusion. The peak-to-peak amplitude of the cochlear microphonic at high sound intensities was reduced however the drug was administered. After a period of time ranging from 1-4 h following drug application, cochleae were fixed and prepared for scanning electron microscopy to examine the hair cells. Changes in the hair bundles from basal turns tended to be more extensive than those of more apical turns. Initially there was an increase in the granularity of the surface of the stereociliary membrane and a tendency for cross-links to swell, stretch and break. Later, the surface texture of stereocilia became smoother than normal, and hair cells in the basal turns showed extensive erosion and fracture of cross-links. Tip links could survive even when extensively stretched. It is possible that the morphological changes in stereocilia reported here do not arise from direct actions of furosemide, but indirectly, from perturbations of the ionic composition of cochlear fluids induced by effects of the drug upon the stria vascularis.

Animals↗