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Biomedical subjects

P Hayes

Publications and source records attributed to P Hayes.

At least 19 recordsLinked to original sources
PubMed1998

Increase in plasma viral load after oral cholera immunization of HIV-infected subjects.

OBJECTIVE: Constant antigenic stimulation of the large immune cell population contained within gut-associated lymphoid tissue during HIV infection may contribute to patients' total viral load. The aim of this investigation was to evaluate the effect of a mucosal antigenic challenge on HIV replication. DESIGN: Prospective clinical study. METHODS: Twelve HIV-1-infected men (mean age, 42.3 years) from the Casa de Apoio Santo Antonio, Rio de Janeiro, Brazil, were immunized with combined whole cell-toxin B subunit oral cholera vaccine. Blood was collected on days 0, 2, 4, 6, 10 and 15 after immunization and plasma was tested for cholera toxin-specific antibody response (IgG and IgA), beta2-microglobulin, and plasma viral load. CD4 lymphocyte counts were performed within 1 week before immunization. Five HIV-infected non-immunized individuals were studied as controls. RESULTS: There were no adverse effects following immunization and no deterioration in clinical outcome during 3 months of follow-up. A transient increase in viral load that ranged from twofold to 60-fold was observed in all cases and was statistically significant on days 2, 6 and 10 (P = 0.017, P = 0.025, P = 0.021, respectively). There was no correlation with CD4 cell counts. None of the non-immunized subjects demonstrated the pattern of viraemia observed after immunization (P > 0.10 on all days). CONCLUSIONS: Our data indicate that mucosal immunization with oral cholera vaccine induces a transient increase in HIV viraemia, regardless of clinical stage of infection and CD4 cell counts. These findings suggest that mucosal stimulation of HIV-infected patients enhances HIV replication.

Administration, Oral↗
PubMed1998

The C-reactive protein to prealbumin ratio correlates with the severity of multiple organ dysfunction.

BACKGROUND: This study evaluates the correlation between a ratio of two hepatic proteins, C-reactive protein (CRP) and prealbumin (PALB), and the severity of organ dysfunction as measured by the multiple organ dysfunction score (MODS). METHODS: A prospective cohort study was undertaken in critically ill patients (n = 70) by measuring the serum levels of CRP and PALB, the energy expenditure via indirect calorimetry, and severity of organ dysfunction by the MODS. All three variables were recorded for a period of 5 days from admission and then assessed for correlation to each other and to the length of stay and mortality in the intensive care unit. RESULTS: The CRP/PALB ratio showed a statistically significant correlation at 48 hours (r = 0.45, P < .01) and 120 hours (r = 0.53, P < .01). This ratio showed higher degrees of correlation when applied to patients with a diagnosis of sepsis, multiple organ dysfunction, or single organ dysfunction, r = 0.71 and 0.56 at 48 and 120 hours, respectively. Receiver operating characteristics (ROC) curves show that a ratio of 2.07 correlated with a MODS of 16 with a sensitivity of 92% and a specificity of 71%. CONCLUSIONS: This study demonstrates a strong correlation between the severity of organ dysfunction and the ratio of two hepatic proteins, CRP and PALB. There was no correlation between the degree of energy expenditure and the MODS, Acute Physiology and Chronic Health Evaluation II score, or the ratio of CRP/PALB. The use of inflammatory markers may be an easy, inexpensive method of assessing severity of illness in the critically ill.

APACHE↗
PubMed1997

Visual impairment in nursing home residents: the Blue Mountains Eye Study.

OBJECTIVES: To assess the prevalence and causes of visual impairment, and the proportion of treatable eye conditions, among nursing home residents. DESIGN AND SETTING: The Blue Mountains Eye Study is a population-based survey of vision and common eye diseases in people aged 50 or older in two postcode areas west of Sydney. Nursing home examinations were conducted during 1993. PARTICIPANTS: Three representative nursing homes were selected from the nine in the study area. There were 128 residents aged 50 or older (64% females), representing 21% of all eligible nursing home residents in the two postcode areas. MAIN OUTCOME MEASURE: Blindness or visual impairment in one or both eyes. RESULTS: Eye examinations were refused by five nursing home residents, and dementia precluded eye examination in 34 (28%) of the remainder. We found significantly higher prevalences (fivefold increase) of bilateral (11%) and unilateral (21%) blindness in nursing home residents compared with local community residents (bilateral, 0.5%; unilateral, 2%). In seven of the 10 blind nursing home residents, the blindness was potentially reversible (advanced cataract); late age-related macular degeneration (AMD) was the second most frequent cause of blindness, affecting one or both eyes of 12% of residents. Open-angle glaucoma affected 10% and advanced cataract 11%; a history of past cataract surgery was obtained in 14%. CONCLUSIONS: These data confirm earlier reports of a substantial number of treatable eye diseases, particularly advanced cataract, in nursing home residents, and indicate a need for increased surveillance of these communities. The high rate of visual impairment and blindness, compared with similar age groups in the local community, suggests that visual disability may contribute to nursing home placement.

Age Distribution↗
PubMed1997

Homology of AFLP products in three mapping populations of barley.

Segregation of 850 polymorphic AFLP (amplified fragment length polymorphism) fragments was followed in three different doubled haploid (DH) barley populations, Dicktoo x Morex (DM), Igri x Franka (IF) and Blenheim x E224/3 (BE), which had previously been used to construct linkage maps using other molecular markers. The final maps consisted of 310, 655 and 474 markers, of which 234, 194 and 376, respectively, were AFLPs. A comparison of profiles from the parental lines identified 51 similar-sized AFLPs segregating in both DM and IF populations, 20 in the DM and BE populations and 18 in the IF and BE populations. Eight segregated in all three. Analysis of the complete datasets for each of the populations using Joinmap V.2. indicated that in general terms each of the AFLPs which were polymorphic in more than one population mapped to the same genetic locus. The number of co-dominant markers segregating in a single population ranged from 6% for DM to 12.6% for IF. These results are discussed in the context of using AFLP in genetic linkage and diversity studies.

Chromosome Mapping↗
PubMed1997

Human immunodeficiency virus infection impairs hemopoiesis in long-term bone marrow cultures: nonreversal by nucleoside analogues.

Hematologic abnormalities are often seen in patients infected with human immunodeficiency virus (HIV). The effect of HIV infection of bone marrow stroma on support of uninfected CD34 progenitor cells in long-term bone marrow culture (LTBMC) was investigated. Results show that HIV-infected bone marrow stroma was unable to adequately support CD34 progenitor cells in vitro. Zidovudine or didanosine was added to cultures in an attempt to reverse the suppressive effects exerted by HIV and to determine whether such suppression was mediated by transfer of HIV infection to progenitor cells. Didanosine failed to reduce the suppressive effects of HIV, whereas zidovudine compounded the observed suppression. HIV infection of bone marrow stroma, while reducing the production of nonadherent cells, did not increase apoptosis and cell death in such cells. In contrast, zidovudine enhanced apoptosis and cell death in nonadherent cells produced by both HIV-infected and control LTBMC.

Anti-HIV Agents↗
PubMed1996

Investigation of chronic hepatitis C infection in individuals with haemophilia: assessment of invasive and non-invasive methods.

Hepatitis C virus (HCV) infection is the major cause of chronic liver disease in individuals with haemophilia. A wide spectrum of disease severity is found in this group, ranging from mild hepatitis to cirrhosis. We have studied a cohort of 87 anti-HCV positive haemophiliacs who have been infected with HCV for 10-25 years and assessed the relative value of invasive and non-invasive methods of evaluating liver disease. The severity of liver disease was assessed using ultrasound scan (n = 77), upper GI endoscopy (n = 50), laparoscopic liver inspection (n = 33) and liver biopsy (n = 22). Invasive investigations were performed without any significant bleeding complications. Evidence of severe liver disease was found in approximately 25% of patients. There was agreement between the severity of liver histology and the information derived from the laparoscopic liver inspection, endoscopy and ultrasound in 86%. Co-infection with HIV was significantly associated with more severe liver disease (P = 0.006). This study provides further evidence that liver disease is emerging as a major complication in haemophiliacs and severe liver disease is more common in those co-infected with HIV. We have shown the potential value of laparoscopic liver inspection, in combination with endoscopy and ultrasound, in staging the extent of liver disease, and suggest that most patients may be managed without resorting to liver biopsy.

Adolescent↗
PubMed1996

Engagement of adhesion molecules (CD18, CD11a, CD45, CD44, and CD58) enhances human immunodeficiency virus type 1 replication in monocytic cells through a tumor necrosis factor-modulated pathway.

Engagement of monocytic cell membrane proteins was shown to enhance human immunodeficiency virus type 1 (HIV-1) replication in monocytic cells. Cross-linking of CD18, CD11a, or CD45 by immobilized antibodies produced up to an 11-fold enhancement of HIV-1 release in the OM10.1 monocytic cell line in a tumor necrosis factor-alpha (TNF-alpha)-dependent manner. In addition, adhesion of OM10.1 cells to immobilized intercellular adhesion molecule-1 (ligand for CD18/CD11a) induced similar TNF-alpha-dependent enhancement of HIV-1 replication. After phenotypic differentiation of OM10.1 cells, engagement of cell membrane proteins CD18, CD11a, CD44, CD45, or CD58 by soluble antibodies enhanced HIV-1 replication in a TNF-alpha-dependent manner. These data suggest that cross-linkage of monocytic cell membrane proteins during cell-cell interaction and specifically during antigen presentation to CD4 T cells may enhance HIV-1 replication, facilitating infection of adjacent cells.

Antigens, CD↗
PubMed1996

Intra-arterial fibrinolytic treatment for mesenteric arterial embolus: a case report.

The diagnosis of mesenteric ischemia is based on acute clinical awareness of the condition and confirmed by angiography or laparotomy. The standard treatment is abdominal exploration with resection of the gangrenous segment of the bowel or embolectomy of the superior mesentery artery, or both. Alternative treatment such as intra-arterial thrombolysis may be considered in selected patients. A 66-year-old man with a history of atrial fibrillation presented with abdominal pain. Angiography documented an embolus in both the ileocolic artery and a branch of the right renal artery. The patient was treated with selective intra-arterial infusion of streptokinase. The abdominal pain resolved. Repeat angiography showed lysis of both emboli.

Aged↗
PubMed1995

Regional assignment of 30 expressed sequence tags on human chromosome 7 using a somatic cell hybrid panel.

The regional assignments of 30 expressed sequence tags (ESTs) on human chromosome 7 were determined by studying the segregation of their PCR-amplified products in a panel of mouse somatic cell hybrids. ESTs are important molecular landmarks for physical mapping and can be considered as tags to candidate genes for genetically linked human inherited diseases. These results contribute further potential gene sequences to the transcriptional map of chromosome 7.

Animals↗
PubMed1995

[Foreign body reaction after lens implantation. Correlation between visual acuity and density of giant cells].

In the early postoperative stage giant cells often appear on IOLs. Independent of this, a foreign-body reaction may start about 3 months after surgery from posterior synechia. Foreign-body reaction occur more frequently in diabetic patients or patients with glaucoma. In a prospective trial, we examined the surface of the IOLs from 115 patients with diabetes or glaucoma using specular microscopy. We compared the maximal density of the cells to visual acuity. One week and 1 month after surgery, the maximal density of giant cells was between 0 und 20/mm2; vision (median) was independent of the giant cell density in all groups between 20/25 and 20/30. Three months after surgery, the maximal density of giant cells was between 0 und 35/mm2; vision (median) was 20/25 in patients with no giant cells or cell densities up to 15/mm2. Seven patients had cell densities between 16 and 35/mm2; visual acuity (median) was 20/125. The difference was significance was (P < or = 0.05). Six months and 1 year later after surgery, the maximal density of giant cells was between 0 and 41/mm2; the vision (median) in patients with giant cell densities up to 15/mm2 was between 20/20 and 20/25. In five examinations the cell densities were found to be in the range of 16 to 40/mm2; visual acuity (median) was 20/80 in these cases. The difference is not significant (P < or = 0.05). A foreign-body reaction with more than 15 giant cells/mm2 is a rare complication of cataract surgery with lens implantation. Three months after surgery, this complication correlates with poor vision.

Aged↗
PubMed1994

A novel initiator/promoter element within the CD45 upstream region.

Transcripts of the murine hematopoietic cell surface antigen CD45 (also known as Ly-5, LCA, T200 and B220) initiate at three distinct sites--P1a, P1b and P2--within the upstream region, though P1b is the major site of initiation in lymphoid cells. In our studies of the CD45 upstream region, we identified a cluster of nucleotides comprising the P2 start site, called the TC box, that acts as a minimal promoter for transcription from the P2 site. Thus, the TC box is functionally analogous to elements called initiators that direct RNA polymerases to begin transcription at specific positions. However, in contrast with other initiators, the CD45 TC box directs activated tissue specific expression. The TC initiator, therefore, may provide an effective means to achieve broad expression of exogenously introduced genes in immunologically relevant cells.

Animals↗