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Biomedical subjects

A King

Publications and source records attributed to A King.

At least 235 records · Page 13Linked to original sources
PubMed1996

[Clinical usefulness of Multitest in the evaluation of cellular immunity].

The aim of this work was to assess cellular immunity using the Multitest CMI and relate its results with lymphocyte counts and lymphocyte subpopulations determined using monoclonal antibodies against CD4 and CD8 and fluorescence microscopy. We studied 51 patients (31 male), 20 infected with HIV, 18 recurring infections, 5 with cancer, 2 with tuberculosis and 6 with miscellaneous diagnoses. According to Multitest results, patients were classified as normal, hypoergic or anergic. Twenty five percent of patients were normal, 65% hypoergic and 10% anergic. Eighty percent of anergic patients were infected with HIV. No differences in total lymphocyte count were observed between the three groups. CD4 lymphocyte count was lower in anergic patients when compared with the other two groups. All patients with CD4 counts below 200 cells/mm3 were anergic. It is concluded that Multitest CMI is useful for the assessment of cellular immunity and complements the determination of lymphocyte subpopulations.

Adult↗
PubMed1995

Structural comparison of two strains of foot-and-mouth disease virus subtype O1 and a laboratory antigenic variant, G67.

BACKGROUND: Foot-and-mouth disease viruses (FMDVs) are members of the picornavirus family and cause an economically important disease of cloven-hoofed animals. To understand the structural basis of antigenic variation in FMDV, we have determined the structures of two viruses closely related to strain O1BFS whose structure is known. RESULTS: The two new structure are, like O1BFS, both serotype O viruses. The first, O1 Kaüfbeuren (O1K), is a field isolate dating from an outbreak of FMD in Europe in the 1960s. The second, called G67, is a quadruple mutant of O1K, generated in the laboratory, that bears point mutations conferring resistance to neutralizing by monoclonal antibodies, specific for each of the four major antigenic sites defined previously. The availability of the three related virus structures permits a detailed analysis of the way amino acid substitutions influence antigenicity. Structural changes are seen to be limited, in general, to the substituted side chain. For example, the GH loop of VP1, a highly antigenic and mobile protuberance which becomes ordered only under reducing conditions, was essentially indistinguishable in the three viruses despite the accumulation of up to four changes within its 15-residue sequence. At one of the other antigenic sites, however, changes between the two field strains did perturb both side-chain and main-chain structures in the vicinity. CONCLUSIONS: The conservation of conformation of the GH loop of VP1 adds to the evidence implicating an integrin as the cellular receptor for FMDV, since this loop contains a conserved RGD (Arg-Gly-Asp) sequence structurally similar to the same tripeptide in some other integrin-binding proteins. Structural changes required for the virus to escape neutralization by monoclonal antibodies are generally small. The more extensive type of structural change exhibited by the field isolates probably reflects differing selective pressures operating in vivo and in vitro.

Amino Acid Sequence↗
PubMed1995

Accuracy of a saliva test for HIV antibody.

The accuracy of a saliva collection and testing protocol for determination of HIV-1 antibody status was assessed under realistic field conditions. The 1,256 study participants came from two lower-prevalence settings--a self-referral testing clinic (478) and a street-based outreach program (431)--and two high-prevalence clinics--an HIV/AIDS treatment clinic (337) and a hemophilia clinic (10). Saliva was collected using the Omni-Sal collection device and was tested by technicians blind to serum status using a modified protocol that employed the Recombigen HIV-1 EIA. Serum was tested using standard methods. A single saliva enzyme immunoassay (EIA) correctly identified 358 of 368 seropositive individuals, for a sensitivity of 97.3% (95% CI: 95.1%-98.7), and 888 of 888 seronegative individuals, for a specificity of 100% (95% CI: 99.6-100). Confirmation of saliva EIA positives with a repeat saliva EIA and an in-house saliva radioimmunoprecipitation assay resulted in a substantial drop in sensitivity to 85.3% (95% CI: 81.0-89.0). We conclude that a single saliva EIA using the modified test protocol described is sufficiently accurate for surveillance purposes, but we do not recommend it for diagnostic purposes or screening.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Concurrent radiation therapy and chemotherapy in the treatment of primary squamous cell carcinoma of the vulva.

BACKGROUND: Interest in combined modality treatment and in quality of life issues may affect the choice of radical vulvectomy as the treatment of choice in many vulvar carcinomas. To evaluate the potential role of combined radiation and chemotherapy with or without local excision as primary treatment for squamous cell carcinoma of the vulva, the outccomes of 19 patients with this disease treated with combination therapy were reviewed. METHODS: Nineteen patients were treated between September 1987 and October 1992. Fifteen patients had American Joint Committee on Cancer Stage III disease; 4 had Stage II. All had clinically negative inguinal lymph nodes with the exception of two patients who had positive ipsilateral inguinal nodes that were removed before treatment. The patients received 45-50 Gy to the pelvis and inguinal nodes with concurrent chemotherapy that consisted of 5-fluorouracil given as a 96-hour continuous infusion (1000 mg/m2/d) during weeks 1 and 5 of radiation. A single dose of mitomycin-C (10 mg/m2) during the first day of chemotherapy has been used since November 1991. Ten patients were boosted with implants or electrons and 6 others underwent local excision. RESULTS: The median follow-up was 34 months. Responses were determined clinically 1 month after completion of the radiation and chemotherapy. Clinically, complete responses were obtained in 10 patients (53%), partial responses in 7 (37%), and no response in 1; 1 patient progressed during treatment. The combined modality therapy (radiation/chemotherapy/with or without wide local excision) resulted in a local control rate of 74% (14/19). All five treatment failures occurred within 6 months of treatment. Four of these patients were rendered disease free by radical vulvectomy and/or exenteration, for an overall local control rate of 95% (18/19). CONCLUSION: Concurrent radiation therapy and chemotherapy with local excision performed as needed, appears to be a reasonable alternative to radical vulvectomy in patients with primary squamous cell carcinoma of the vulva. Radical surgery remains a viable option for patients in whom primary therapy has failed.

Adult↗
PubMed1995

The role of integrins in adhesion of decidual NK cells to extracellular matrix and decidual stromal cells.

At the time of implantation, the decidua is infiltrated by a unique population of NK cells with large granular lymphocyte morphology, which are thought to influence placental trophoblast invasion and differentiation. The mechanisms used by these cells to migrate within decidua are not known, but in other biological processes such as wound healing and tumor invasion cell-matrix interactions are important. These interactions are mediated by specific receptors, mostly belonging to the family of integrins. Decidual NK cells are observed to bind to type IV collagen and fibronectin, but not to laminin. Adhesion to collagen was inhibited with an anti-alpha 1 integrin subunit mAb, whereas adhesion to fibronectin was blocked with anti-alpha 4, -alpha 5, and -beta 1 integrin subunit mAbs. Binding of decidual NK cells to decidual stromal cells was partially blocked with mAbs to the alpha 4 and alpha 5 integrin subunits. These results provide insight into the possible mechanisms utilized by decidual NK cells for migration and retention within the pregnant uterine mucosa.

3T3 Cells↗
PubMed1995

Screening for cytokine mRNA in human villous and extravillous trophoblasts using the reverse-transcriptase polymerase chain reaction (RT-PCR).

During the process of placental implantation, sessile villous trophoblast cells migrate from the villi into the decidua as isolated motile extravillous trophoblast cells. There is differential expression of the epidermal growth factor-receptor (EGF-R) and c-erbB2 proteins on villous and extravillous trophoblast populations. Using monoclonal antibodies to EGF-R and c-erbB2, we have obtained highly purified populations of villous and extravillous trophoblast by fluorescence activated cell sorting. These cells were examined by the reverse transcriptase-polymerase chain reaction (RT-PCR) using nested internal primer pairs for the following cytokines: CSF-1, GM-CSF, TNF-alpha, TGF-beta1, IFN-gamma, IL-2, LIF and also for LIF-receptor. TNF-alpha and TGF-beta 1 were present in all trophoblast populations. GM-CSF and CSF-1 were only found in some samples, with preferential expression of CSF-1 in villous populations. IFN-gamma, IL-2 and LIF mRNA were not found, although all samples contained LIF-receptor mRNA. These cytokines (CSF-1, TGF-beta, TNF-alpha and GM-CSF) are likely to influence trophoblast growth and differentiation in an autocrine manner, since their receptors are also present on trophoblast. These results illustrate a quick and simple method to analyse for the presence of cytokine and other transcripts in trophoblast subpopulations during early pregnancy.

Base Sequence↗
PubMed1995

Blastocysts exhibit preferential uptake of DNA fragments from the E6-E7 conserved region of the human papillomavirus.

The objective of the study was to determine if embryos at the blastocyst stage differentially took up exogenous human papillomavirus (HPV) DNA derived from the different HPV types and to determine whether the capture process was active or passive. In vivo fertilized mouse embryos were cultured to the blastocyst stage in vitro. The mouse blastocysts were incubated for 2 hr in the presence of a mixture of exogenous DNA fragments derived from HPV types 6b, 11, 16, and 18. The blastocysts were rigorously washed and analyzed for differential uptake of HPV gene sequences using the polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis. PCR analysis detected HPV type 18 in only 40% of the blastocyst groups while detecting the other HPV types in 100% of the blastocysts. The negative control group did not show HPV DNA after PCR ruling out possible PCR artifacts. Formalin-fixed blastocysts also showed uptake of HPV DNA. In conclusion, the data suggest a role for embryos as passive vectors for foreign DNA and that the degree of DNA uptake varies with different types of HPV DNA.

Absorption↗
PubMed1995

Cyclophosphamide induced remission in relapsed, progressive idiopathic orbital inflammation ('Pseudotumour').

A patient with orbital pseudotumour with intracranial extension is reported. At presentation, the disease was confined to the orbit. Steroid therapy and orbital irradiation failed to control the condition, which then extended intracranially. Progression continued in spite of further treatment with cranial irradiation and azathioprine. Cyclophosphamide was introduced, which produced a dramatic clinical response with marked radiological improvement within a few months. This was maintained over 2 years.

Administration, Oral↗
PubMed1995

Resistance to imipenem in Pseudomonas aeruginosa.

There was a slow increase in imipenem resistance in Pseudomonas aeruginosa at St. Thomas' Hospital in the 1990s, reaching 3% in 1994. Of the 94 imipenem-resistant strains, 69% were susceptible to all the other agents tested; 15% were also resistant to one other antibiotic, 5.3% to two, 6.4% to three, 4.3% to four or more compounds. 16% of strains were resistant to at least one other beta-lactam in addition to imipenem. Resistance to other antibiotics was more common among the strains for which imipenem MICs were 4 mg/L than among either imipenem-susceptible or imipenem-resistant (MICs > or = 8 mg/L) strains.

Anti-Bacterial Agents↗
PubMed1995

In-vitro activity of purpuromycin and MDL 63,604 against microorganisms that cause vaginitis and vaginosis.

Purpuromycin and its semi-synthetic derivative MDL 63,604 had in-vitro activity similar to that of amphotericin B against isolates of Candida albicans. MDL 63,604 had activity similar to that of metronidazole against Trichomonas vaginalis. Both compounds were very active against most species of Gram-positive and Gram-negative anaerobes and against Gardnerella vaginalis. MDL 63,604 had significantly lower MICs than purpuromycin against T. vaginalis and most of the bacteria, probably due to antagonism of purpuromycin's activity by medium supplements (blood or serum). Purpuromycin or related compounds may have a potential role in the topical treatment of vaginitis and vaginosis.

Amphotericin B↗
PubMed1995

Secretion of colony stimulating factor-1 by human first trimester placental and decidual cell populations and the effect of this cytokine on trophoblast thymidine uptake in vitro.

The present in-vitro study using an enzyme-linked immunosorbent assay has identified the cell types responsible for colony stimulating factor-1 (CSF-1) production at the first trimester human placental uterine interface. The major sources were observed to be decidual stromal cells and decidual CD56+ natural killer (NK) cells, but decidual CD3+ T cells did not produce CSF-1, reflecting functional differences between these two decidual lymphoid populations. Of a variety of cytokines tested, only interleukin-2 (IL-2) was found to augment CSF-1 secretion by decidual NK cells. Trophoblast cells also secreted CSF-1, but the amounts were small relative to decidual stromal cells and NK cells. Therefore, most of the CSF-1 present at the implantation site appears to be maternally derived. Co-culture of decidual NK cells on a monolayer of irradiated trophoblast did not augment CSF-1 secretion by decidual NK cells, indicating that the production of this cytokine is not stimulated by contact with fetal trophoblast. CSF-1 was found to increase [3H]thymidine uptake by trophoblast cultured on laminin for 72 h, but no such response was seen in trophoblast cultured on fibronectin, indicating that these extracellular matrix proteins have differential effects on the response of trophoblast to this cytokine.

CD56 Antigen↗
PubMed1995

Human trophoblast adhesion to matrix proteins: inhibition and signal transduction.

At the time of implantation, the extracellular matrix proteins laminin and fibronectin are abundant in the decidua and are distributed pericellularly around each individual stromal cell. First trimester human trophoblast expresses both laminin and fibronectin receptors, specifically the alpha 1 beta 1, alpha 5 beta 1, alpha 6 beta 1 and alpha 6 beta 4 integrin heterodimers. In this study we have demonstrated that in-vitro adhesion of first trimester human trophoblast to purified extracellular matrix proteins and to purified decidual stromal cell monolayers can be inhibited by monoclonal antibodies directed against appropriate integrin subunits and by synthetic peptides containing an arginine-glycine-aspartic acid sequence. Monoclonal antibodies (mAbs) to the alpha 5 and beta 1 integrin subunits and a synthetic peptide significantly inhibited adhesion to fibronectin. Binding of trophoblast to laminin was blocked with mAbs to the alpha 6 and beta 1 but not alpha 1 and beta 4 integrin subunits. Similarly, integrin-mediated adhesion to monolayers of decidual stromal cells could be blocked with mAbs to the alpha 5, alpha 6, beta 1 and beta 4 integrin subunits. Integrin-mediated signal transduction in normal and malignant trophoblast was investigated by Western blotting. A 115 kDa protein was the major tyrosine phosphorylated protein detected in trophoblast after binding to laminin or fibronectin. The profile of tyrosine phosphorylated proteins differed for malignant trophoblast.

3T3 Cells↗
PubMed1995

Comparisons of risk factors for HIV-1 infection in Jefferson and Mobile County, Alabama.

A study of the Alabama state AIDS database was conducted to determine whether differences exist in demographic and risk characteristics between patients with HIV-1 in Jefferson and Mobile County. The authors found that the age distribution of patients with HIV-1, the percent of those having AIDS, and the percent of those surviving were very similar. However, significant differences existed in patient-reported risk factors in the two counties. Homosexuality was reported as the major risk factor in both counties. However, there was proportionately more homosexuality reported in Jefferson County and, conversely, more heterosexuality reported in Mobile. There also were significant differences in race and gender distributions in the two counties. This was due in part to the proportionately higher prevalence of African American females of reproductive age with HIV-1 in Mobile County. This may pose a significantly greater risk for pediatric AIDS among African American females in Mobile County.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Giving permission to embodied knowing to inform nursing research methodology: the poetics of voice(s).

This paper originated from my experience of trying to find an authentic way to research women's experience of the premenstrum. I describe how personal change informed an evolving methodological approach. This change occurred when I felt tension between two strong voices. Conflict and insecurities originated from the pressure of my academic voice to conform to the dominant culture in what often seemed a disempowering way; a way that denied my body voice by emphasizing theory over experience. The construction of a poetic of voice(s) to illustrate how I eventually found an embodied voice is used to provide space for the reader's own interpretive process. The evolving embodied voice integrates my experience as a woman/nurse/researcher, validating my knowing bodily, practically, experientially and academically that I was able to help the participants to disclose their embodied knowing. This approach has wider implications when considering the value nurse researchers and academics give to embodied wisdom.

Conflict, Psychological↗