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O Sharma

Publications and source records attributed to O Sharma.

15 recordsLinked to original sources
PubMed1998

HIV quantitation in spiked vaginocervical secretions: lack of non-specific inhibitory factors. DATRI 005 Study Team. Division of AIDS Treatment Research Initiative.

The objective of this study was to assess the effect of menstrual phase on the ability to quantitate HIV-1 in vaginocervical secretions (VCS) through reconstruction experiments with HIV seronegative VCS collected throughout the menstrual cycle. Measurement of HIV-1 inoculated into both fresh and frozen VCS was undertaken by quantitative micro co-culture, p24 antigen assay and polymerase chain reaction (PCR) for both HIV-1 RNA and pro-viral DNA. Two laboratories carried out these assays over a range of viral concentrations. The study involved a randomized factorial design and the factors were: (1) diluents (phases of the menstrual cycle and controls); (2) laboratories; (3) stock concentrations; and (4) frozen versus fresh VCS samples. Each assay was assessed independently using a random effects analysis of variance (ANOVA) model. No statistical differences due to menstrual cycle were seen in the assay results of p24 antigen (P = 0.08), PBMC culture (P = 0.74), plasma culture (P = 0.13), cell-free RNA (P = 0.44), cell-associated RNA (P = 0.58) and cell-associated DNA (P = 0.43). Inter-laboratory differences were statistically significant for cell-free RNA (P < 0.001), cell-associated DNA (P < 0.001) and p24 (P < 0.001). It is concluded that VCS obtained throughout the menstrual cycle from HIV-uninfected women lacks intrinsic inhibitory factors which could limit detection and quantification by antigen, culture or nucleic acid-based technologies for HIV-1 in VCS throughout the menstrual cycle. Using a standardized collection procedure, we suggest that variation in HIV quantity over time, when reported in VCS of infected women, should be attributed to HIV-associated biologic factors, rather than non-specific or other technical factors.

Analysis of Variance↗
PubMed1998

Diagnostic pitfalls in asthma.

Asthma is a common disease, diagnosed and treated routinely, that still lacks a clear, universally accepted definition. The diagnosis, made mostly by history and physical diagnosis, is often supported by peak flow rate or spirometric measurements. This time-honored approach may prove to be unreliable, resulting in overdiagnosis of the disease. The literature is replete with reports about patients treated as if they had asthma in whom other pulmonary diseases were eventually diagnosed. The incidence of asthma is increasing; there seems to be a lower threshold now for making this diagnosis. Overdiagnosis can be avoided, however, by systematic evaluation and complete pulmonary function testing. This paper presents two examples of clinical carelessness resulting in diagnostic delay of underlying disorders mimicking bronchial asthma.

Amyotrophic Lateral Sclerosis↗
PubMed1995

Blunt gallbladder injuries: presentation of twenty-two cases with review of the literature.

Blunt injuries to the gallbladder are very uncommon, whereas penetrating gallbladder trauma occurs more frequently. Over the last 19-year period through 1994, 22 cases with blunt gallbladder trauma were treated. Avulsion (partial or complete) and contusion were observed in 10 cases each (45%). Perforation of the gallbladder and traumatic cholecystitis with necrosis were seen in one case each. Associated intra-abdominal trauma was present in 100% of the cases and accounted for both mortalities. Gallbladder injury was diagnosed after celiotomy, except for one case that was diagnosed and treated nonoperatively. Based on the experiences gained herein and an extensive review of the literature, a classification scheme for gallbladder trauma and its treatment is presented.

Adolescent↗
PubMed1994

Mechanisms of HIV/SIV mucosal transmission.

The Division of AIDS (DAIDS), National Institute of Allergy and Infectious Diseases (NIAID), organized a Workshop on HIV/SIV Pathogenesis and Mucosal Transmission on March 14-17, 1994, attended by over 300 participants. The purpose of the workshop was to foster research in the areas of HIV pathogenesis, mucosal transmission, and host factors modulating HIV infection and disease. This article summarizes workshop presentations that focused on mechanisms of HIV or SIV mucosal transmission. The following are highlights from the workshop. The epidemiological data indicating a low probability of infection from a single sexual exposure are consistent with observations that infectious cell-free or cell-associated HIV could be isolated from only 10-57% of semen samples, and that high levels of SIV are required for infection by a mucosal route. Several lines of circumstantial evidence suggest that an important property of a transmitted HIV or SIV is the ability to infect macrophages. A potential mechanism for cell-associated mucosal transmission is provided by the observations that CD4-negative epithelial cells in culture are efficiently infected by direct contact with HIV-infected T cells, and that HIV-infected epithelial cells are observed in vivo. Cell-free HIV virions contain partial reverse transcripts of viral RNA into DNA, and conditions that promote DNA reverse transcripts, such as incubation in seminal fluid, increase viral infectivity. Finally, evidence is accumulating that transient or abortive infection with short-term recovery of infectious virus in blood can occur in the absence of seroconversion.

Animals↗
PubMed1993

Pneumocystis carinii pneumonia in HIV infected patients: effects of the diseases on glutathione and glutathione disulfide.

Human immunodeficiency virus (HIV) infection is associated with altered levels of glutathione (GSH) in cells and extracellular fluids. GSH is essential for lymphocyte proliferation and inhibits HIV replication. Therefore, determination of GSH and glutathione disulfide (GSSG) levels could be useful as indicators of the progression of the disease. Thyroid hormone levels are altered in acquired immuno-deficiency syndrome (AIDS), such that thyroid hormone might be a useful prognostic indicator of the severity of AIDS. Pneumocystis carinii pneumonia (PCP) is a debilitating disease of the lung that can accompany HIV infection. The effects of pulmonary infections were assessed in AIDS patients on thyroid hormone, GSH, GSSG levels and other parameters. Two groups of AIDS patients were selected, a group with PCP and a control group with other respiratory diseases. GSH was evaluated in plasma, pulmonary lavage fluid, pulmonary biopsy tissue and buccal cells. Levels of GSSG in pulmonary lavage fluid were higher in PCP patients than in controls, which suggests that PCP patients suffer from oxygen radical toxicity in their lungs. PCP patients may have altered plasma GSH utilization such that damaged lung tissue may become less efficient at using plasma GSH. Patients with PCP may have altered CD4 cell functions such that thyroid hormone levels do not correlate with CD4 cell counts. Patients with AIDS and secondary infections of the lung were found to have altered GSH redox states, probably indicative of physiologic adaptation to AIDS.

AIDS-Related Opportunistic Infections↗
PubMed1984

Immunopathologic and clinical studies in pulmonary hypertension associated with systemic lupus erythematosus.

PH is an uncommon manifestation of SLE. The symptoms of PH develop within a few years after the onset of the multisystem disease. The most common presenting complaints of SLE patients with PH are dyspnea on exertion, chest pain, nonproductive cough, edema, and fatigue or weakness. The important physical findings are a loud second pulmonic heart sound and a right ventricular lift. The chest roentgenogram shows a cardiomegaly, a prominent pulmonary segment, and usually clear lung fields. Pulmonary function tests may show evidence of restrictive lung disease; however, the physiologic abnormalities are mild and out of proportion to the severity of the PH. The diagnosis of PH is established by cardiac catheterization showing elevated pulmonary artery pressure, normal capillary wedge pressure, and no evidence of intracardiac or extracardiac shunts. Pathologic examination of the lung demonstrates angiomatoid lesions involving muscular pulmonary arteries. There is a thickening of the media and subintima of the arterioles. Immunoglobulin and complement deposits are found in the walls of pulmonary arteries. Immunoglobulin eluted from the lung contains rheumatoid factor and antinuclear antibody including antibody to DNA activity. DNA antigen is also present in walls of blood vessels. These results suggest an immune complex deposition process as a mechanism in the pathogenesis of PH in SLE. The clinical course of PH in SLE is variable. Symptoms may be mild and the disease follows a stable and protracted course for several years. It can, however, develop a progressive course ending in death in a few years. The clinical response of SLE patients with PH to treatment with high doses of systemic corticosteroids is not consistent or predictable.

Adrenal Cortex Hormones↗