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H Gay

Publications and source records attributed to H Gay.

At least 19 recordsLinked to original sources
PubMed2001

Infrequent detection of HIV-1-specific, but not cytomegalovirus-specific, CD8(+) T cell responses in young HIV-1-infected infants.

Early potent combination antiretroviral therapies (ART) for HIV-1 infection can preserve or restore immune function, but control of viral replication early in infection may interfere with the development of HIV-1-specific immune responses. Using an IFN-gamma ELISPOT assay, we evaluated the breadth and intensity of HIV-1-specific CD8(+) T cell responses in 17 vertically infected infants who began ART at 1-23 mo of age. CMV-specific responses were also characterized in three infants coinfected with HIV-1 and CMV. Before ART, HIV-1-specific CD8(+) T cell responses were detected in two of 13 (15%) infants <6 mo of age. HIV-1-specific CD8(+) T cells became undetectable in these two infants after the control of viral replication. Intermittent HIV-1-specific responses were noted in six infants who did not experience durable control of viral replication. In contrast, HIV-1-specific responses were detected before ART in four of four infants >6 mo of age and became persistently undetectable in only one child. CMV-specific CD8(+) T cell responses were persistently detected in all HIV-1 and CMV coinfected infants. In conclusion, HIV-1-specific CD8(+) T cell responses were less commonly detected before therapy in young infants than in older infants. Suppression of viral replication appeared to interfere with the development and maintenance of HIV-1-specific CD8(+) T cell responses. The detection of CMV-specific responses in HIV-1 and CMV coinfected infants suggests a selective defect in the generation or maintenance of HIV-1-specific CD8(+) T cell responses. Therapeutic HIV-1 vaccine strategies in young infants may prolong the clinical benefit of ART by expanding the HIV-1-specific CD8(+) T cell pool.

AIDS-Related Opportunistic Infections↗
PubMed2000

The impact of zidovudine use in HIV-infected pregnant women on vertical transmission of HIV in Mississippi.

In February 1994, results of a large placebo-controlled trial of zidovudine (ZDV) use during pregnancy (ACTG 076) showed a dramatic reduction in vertical transmission of HIV. In August 1994, the Public Health Service (PHS) recommended routine ZDV use in HIV infected pregnant women and their neonates for the prevention of vertical transmission. We retrospectively reviewed vertical transmission rates of HIV in Mississippi from 1/1/90 to 8/30/94 before the PHS guidelines were released and from 9/1/94 to 12/31/97 after the PHS guidelines were released. We also reviewed data on ZDV use in HIV infected pregnant women and their neonates from 9/1/94 to 12/31/97. Antenatal, intrapartum and neonatal ZDV use increased from 61%, 59% and 73% respectively to 79%, 77% and 92% respectively. After 9/1/94, vertical transmission rates fell by 44%. Zidovudine use during pregnancy has increased in Mississippi since release of the PHS guidelines resulting in a dramatic decline in vertical transmission rates.

Anti-HIV Agents↗
PubMed1999

Explaining the universe: Herbert Spencer's attempt to synthesize political and evolutionary ideas.

Herbert Spencer's evolutionary ideas related not just to the biological world but to the universe and everything in it. Human societies were also viewed through his evolutionary lens so that Spencer's evolutionary and political ideas are inextricably entwined. This essay looks at some of Spencer's ideas and attempts to locate them in the social and intellectual context of his youth. It also speculates on the rise and fall of Spencer's reputation.

Biological Evolution↗
PubMed1989

Hematologic monitoring in children with epilepsy treated with carbamazepine.

One hundred seventy-six children treated with carbamazepine for epilepsy were monitored over a 12-month period to determine the effects of carbamazepine on the hematologic system. There were no significant changes within the total population in the mean hematocrit or platelet count. The white blood cell count and total neutrophil count showed declines at 1, 8, and 12 months, but the differences did not achieve statistical significance. There was no correlation between the hematologic parameters and carbamazepine blood level, age or sex, or the presence of other drugs. Pretreatment leukopenia and neutropenia were present in 2.8% and 4.0% of children, respectively. During carbamazepine therapy, 8.0% and 17.0% of the children developed leukopenia and neutropenia, respectively, and it was persistent in 1.7% and 2.8%, respectively. The changes in the white blood cell count could be attributed to the changes in the total neutrophil count.

Agranulocytosis↗
PubMed1988

Flow cytometric detection of herpes simplex virus type 2 infected and transformed cells by immunoenzymatic and by indirect immunofluorescence staining.

The glucose oxidase antiglucose oxidase (GAG) immunoenzymatic staining procedure has been used to detect herpes simplex virus (HSV) antigens microscopically. In this study, the GAG procedure was adapted to cells in suspension, and its potential usefulness in flow cytometry was examined. HSV-2 infected monkey kidney and HSV-2 transformed mouse cells were stained using antisera to HSV-2 or to an HSV-2 specific protein with a molecular weight of 38 Kd, respectively, with the GAG procedure. Flow cytometric analysis of the GAG stained cells was then performed by the measurement of scattered light intensity in the angular intervals 1 degree-2 degrees, 2.5 degrees-19 degrees, and 3 degrees-6 degrees. The greatest scattered light intensity decrement caused by staining occurred in the 3 degrees-6 degrees angular interval, as predicted by previous work. In infected cells, which stain intensely by immunofluorescence, the difference between positively and negatively stained cells was adequate for detecting infected cells using the GAG method; however, this was not the case for the lightly staining transformed cells. The indirect immunofluorescence method of analysis of the same populations was superior to the scattered light method of analysis of the GAG stained infected and transformed cells.

Animals↗
PubMed1987

The sensitivity of bladder wash flow cytometry, bladder wash cytology, and voided cytology in the detection of bladder carcinoma.

The sensitivity of voided urinary cytology (VUC), bladder wash cytology (BWC), and bladder wash flow cytometry (BWFCM) in detecting cancer was studied in 70 patients with biopsy-proven bladder tumors. There were 11 Grade I papillomas, 14 Grade II TA, 18 Grade II-III TIS, 19 Grade II-III T1, and eight Grade II-III T2 carcinomas. One to five VUCs per patient (mean, 2.63) were obtained within the 24 hours preceding biopsy. At endoscopy a bladder wash specimen was obtained and divided for cytologic and flow cytometric examinations. For all tumor categories combined, the sensitivity for one, two, and three voided cytology examinations per patient was 41%, 41%, and 60%, respectively. The sensitivity of a single BWC was 61%, of a single BWFCM, 83%. Thus, one BWFCM is more sensitive than three VUC (binomial test; P = 0.006); one BWC is more sensitive than two VUC (P = 0.01); and one BWFCM is more sensitive than one BWC (P = 0.003). These findings remain significant when papillomas are excluded from the analysis (P less than or equal to 0.03) and when papillomas and T2 tumors are jointly excluded (P less than or equal to 0.02). Only four of 70 patients (6%) had their cancers detected by VUC and/or BWC rather than BWFCM. In summary, irrigation cytology specimens are more sensitive than voided urinary cytology, and bladder wash flow cytometry is more sensitive than either in diagnosing bladder cancer. Flow cytometry is more sensitive because of the better sampling of bladder irrigation compared with voided urine and because of the measurement technique itself.

Biopsy↗
PubMed1987

The sensitivity of flow cytometry compared with conventional cytology in the detection of superficial bladder carcinoma.

Three groups of patients with superficial bladder carcinoma were studied: 110 patients had carcinoma in situ (TIS), 54 had noninvasive papillary transitional cell carcinoma (TA), and 64 had transitional cell carcinoma infiltrating the lamina propria (T1). One to six conventional cytologic examinations per patient (mean 2.8) were obtained during the 24 hour period before biopsy. For all tumor categories combined, the sensitivity was 49%, 54%, 62%, and 66% for one, two, three, and four cytologic examinations per patient, respectively. Cytologic sensitivity varied according to tumor category; it was greater in the TIS and T1 categories than in the TA category. To compare with the cytologic results, a subset of 103 patients had bladder irrigation performed immediately before the biopsy which was subsequently analyzed by flow cytometry. The sensitivity of a single flow cytometric examination for all tumor categories combined was 78%. As with the cytologic examinations, the sensitivity of flow cytometry varied with tumor category; it was greater in TIS and T1 categories than in the TA category. The sensitivity of one flow cytometric examination was superior (binomial test, P less than or equal to 0.05) to that of one or two cytologic examinations for TA tumors and to that of one, two, or three cytologic examinations for TIS, T1, and all tumor categories combined. Only three of 103 patients had their cancers detected by cytologic examination and not by flow cytometry.

Carcinoma in Situ↗
PubMed1987

Flow cytometry of prostate cancer: relationship of DNA content to survival.

Between March 1970 and December 1978 there were 366 patients with prostatic cancer treated by 125I seed implants and pelvic lymph node dissection. All had a minimum of 5 years follow-up. One hundred thirty-three patients had metastatic prostatic cancer in lymph nodes (Stage D1) at the time of lymph node dissection and seed implantation. Ninety-one of the 133 patients were judged to have sufficient metastatic prostatic cancer in their nodal tissue (greater than 50% replacement with tumor) to justify flow cytometric cellular DNA measurements on the involved paraffin-embedded nodal tissue. Nine patients were excluded due to uninterpretable DNA histograms leaving 82 patients for analysis. Forty-nine patients had aneuploid and 33 had diploid tumors. There was no statistical bias between the aneuploid and diploid groups due to age (P = 0.970, chi 2 test), time between diagnosis and implantation (P = 0.217, chi 2 test), number of positive nodes (P = 0.669, two-sample t test of means), or tumor grade (P = 0.332, chi 2 test). Median survival time of the aneuploid and diploid groups was 5.0 and 8.8 years, respectively (P = 0.0109, log rank test). Cox regression analysis confirmed the effect of aneuploidy versus diploidy on survival by controlling for other potentially confounding variables (age, time from diagnosis to implantation, number of positive nodes, and grade). Grade as a predictor of survival did not approach statistical significance in this series of relatively small size (P = 0.116). Thirty-eight of the 82 patients had moderately differentiated neoplasms. Nineteen of these were aneuploid and 19 diploid. The median survival was 5.8 and 9.1 years, respectively, for these grade-matched aneuploid and diploid groups (P = 0.039, log rank test). We conclude that flow cytometric DNA measurements on archived paraffin-embedded tumor in nodal metastases appear to be a strong predictor of survival for Stage DI prostatic cancer.

Aneuploidy↗
PubMed1987

Monitoring endoscopic treatment of superficial bladder carcinoma by postoperative urinary cytology.

Transurethral resection was the only modality of treatment in 39 patients with long-standing, recurrent, superficial bladder carcinoma. Postoperative urinary cytology was performed within 3 days of each endoscopy. Tumor recurrence was defined by the presence of a positive biopsy or visible papillary tumors on followup cystoscopic examination. Tumor recurred in 38 patients (97.4 per cent) and 1 patient (2.6 per cent) has remained free of disease 74 months following transient positive postoperative cytology. Among the 38 recurrences 15 (39.5 per cent) were positive, 3 (7.9 per cent) suspicious and 20 (52.6 per cent) negative at the postoperative cytological examination. The interval to recurrence did not differ significantly among the 3 groups. The failure of a negative postoperative cytology study to predict a durable response to treatment by transurethral resection reflects the polychronotopic nature of superficial bladder tumors in this select patient population and suggests the need for adjuvant therapy.

Carcinoma, Transitional Cell↗
PubMed1987

Monitoring intravesical bacillus Calmette-Guerin treatment of superficial bladder carcinoma by postoperative urinary cytology.

We studied 51 patients with superficial bladder carcinoma who had been treated with transurethral resection of all gross tumor followed by intravesical bacillus Calmette-Guerin weekly for 6 weeks. Within 72 hours of either the first or second quarterly cystoscopic surveillance examination after bacillus Calmette-Guerin therapy, a conventional cytology study was obtained. Of these patients 8 (15.7 per cent) had positive, 9 (17.6 per cent) suspicious and 34 (66.7 per cent) negative postoperative cytology studies. Subsequent tumor recurrence was defined as a positive biopsy or visible papillary tumors on cystoscopic examination. All 8 patients with a positive postoperative cytology study had tumor recurrence at a median interval of 4 months. Of the 9 patients with a suspicious study 7 (77.8 per cent) had recurrent tumor at a median interval of 7 months and 2 (22.2 per cent) had no evidence of disease at 16 and 19 months, respectively. Of the 34 patients with a negative postoperative cytology study 13 (38.2 per cent) had tumor recurrence after a median interval of 4 months and 21 (67.8 per cent) had no evidence of disease after a median of 25 months. The tumor recurrence rate in patients with a positive or suspicious postoperative cytology study was significantly greater than that of patients with a negative study (p equals 0.001, Fisher's exact test). Postoperative cytology appears to be a significant prognostic indicator following transurethral resection and intravesical bacillus Calmette-Guerin treatment of superficial bladder carcinoma.

Administration, Intravesical↗
PubMed1986

Monitoring intravesical bacillus Calmette-Guerin treatment of superficial bladder carcinoma by serial flow cytometry.

Simultaneous urinary flow cytometry, cytologic, and cystoscopic examinations were performed at 3-month intervals for a minimum of 1 year on 29 patients receiving intravesical bacillus Calmette-Guerin (BCG) treatment of superficial bladder carcinoma. Flow cytometry (FCM) and cytology were concordant in 57 of 103 examinations; both FCM and cytology were positive in 38 instances, and carcinoma was confirmed by biopsy in 35 (92.1%). In 16 instances FCM and cytology were negative, but carcinoma was present on biopsy in 5 (31.3%). Three examinations were suspicious by both techniques. The 46 determinations with discordant FCM and cytology were subdivided into pathologically confirmed recurrences (25 instances) and no evidence of pathologic and/or cystoscopic disease (21 instances). In the 25 instances of recurrences, FCM was positive in 18 (72.0%), suspicious in 3 (12.0%), and negative in 4 (16.0%), while cytology was positive in 3 (12.0%), suspicious in 9 (36.0%), and negative in 13 (52.0%). Most patients had a severe BCG-induced inflammatory response that caused an elevation of the hyperdiploid population, believed secondary to epithelial regeneration and proliferation. In the 21 instances without detectable recurrence, hyperploidy led to a relatively high proportion of positive (15) and suspicious (4) results by FCM, but only eight had distinct aneuploid populations. It is possible that this latter group, at least, is harboring occult carcinoma. Conventional cytology in the nonrecurrent group was positive in 1 (4.8%), suspicious in 7 (33.3%), and negative in 13 (61.9%). In those instances when tumor was confirmed by biopsy, the false-negative rate for FCM was 19.7%; the false-negative rate for cytology was 40.9%. Thus, FCM appears to be more sensitive but less specific than conventional cytology, having a lower false-negative but a higher false-positive rate. Although serial FCM provides an objective quantitative measure of aneuploid stemlines and hyperdiploid populations in bladder irrigation specimens and can be helpful in following intravesical BCG therapy for superficial bladder carcinoma, it should still be used with conventional cytology. The greatest difficulty with FCM at present, as with conventional cytology, is in cases of marked inflammation. The results reported here were obtained under the most stringent conditions and represent the minimum level of accuracy. Potential improvements in the technique, with the addition of immunologic or other markers, hold hope of further increasing the accuracy of FCM.

Aged↗
PubMed1986

Effect of section thickness on quality of flow cytometric DNA content determinations in paraffin-embedded tissues.

DNA content determinations were carried out by flow cytometry on nuclear suspensions prepared from the same paraffin-embedded tissue block for each of eight surgically resected human carcinomas at section thicknesses of 5,10,20,30,40,50, and 100 millimicrons. Flow cytometric DNA determinations were also obtained on fresh tissue specimens in four of the eight carcinomas. As section thickness decreased below 50 millimicrons, there was a progressive increase in the histogram baseline noise at low DNA values and a decrease in the relative peak height of aneuploid DNA. The former was attributed to an increase of nuclear fragments in thinner sections, and the latter to the greater probability of transection of the larger aneuploid cells within a specimen. Both artifacts were minimized at section thickness of 50 millimicrons or greater.

Breast Neoplasms↗
PubMed1986

Characterization of the tumor-associated 38-kd protein of herpes simplex virus type 2.

The BglII N DNA fragment of herpes simplex virus type 2 (HSV 2), which is capable of oncogenically transforming cells in vitro, encodes a 37,800-dalton (38-kd) protein that has been seroepidemiologically associated with uterine cervical carcinoma. Polyclonal monospecific antiserum was produced against electrophoretically purified 38 kd from HSV 2-infected cells and used to identify antigenic and biochemical characteristics of the protein as well as to probe transformed cells for the expression of viral 38 kd. The HSV 2 type specificity of the 38-kd protein, previously shown using anti-HSV 2 serum and monoclonal antibodies, was confirmed using anti-38-kd serum. The 38-kd protein of HSV 2 produced in vivo and in vitro displayed type specificity and showed no evidence of posttranslational processing. The 38-kd protein has a relative isoelectric point of 9.1, is synthesized at a maximum level four hours after infection and appears to be a component of the virion. When 35S-methionine radiolabeled 38 kd was immunoprecipitated by anti-38-kd serum, high-molecular-weight proteins (118-140 kd) were also present. However, if prior to reacting with the anti-38-kd serum the high-molecular-weight proteins were separated from 38 kd with sodium dodecyl sulphate-polyacrylamide gel electrophoresis, the only reaction observed with immunoblot was with 38 kd. Therefore, the observed coprecipitation appears to result from the formation of a complex between the proteins and is not the result of shared antigenic determinants. Cells transformed by inactivated HSV 2 were examined for the expression of the 38-kd protein using immunoenzymatic staining. The viral 38-kd protein was not consistently found, but since the protein is reported to be a component of the viral enzyme complex ribonucleotide reductase, it cannot be excluded from possible HSV 2 transformation.

Animals↗
PubMed1984

Localization of chromosomal DNA sequences homologous to ribosomal gene type I insertion DNA in Drosophila melanogaster.

Chromosomal sites which have DNA homology to the 1 kb (kilobase pair) BamHI restrictable fragment of the 5 kb type I insertion present in many ribosomal genes in Drosophila melanogaster, were identified by using in situ hybridization and autoradiography. XX and XY complements of polytene chromosomes showed the nucleolus and chromocenter to be heavily labeled. Of the light label over euchromatic regions, the 102C band of chromosome 4 labeled particularly intensely. In mitotic XX and XY complements, the NORs (nucleolus organizer regions) of both sex chromosomes labeled as did the centromeric heterochromatin of autosomes. Label also appeared less frequently over telomeric and euchromatic regions.

Autoradiography↗
PubMed1984

Detection of herpes simplex virus infection using glucose oxidase-antiglucose oxidase immunoenzymatic stain.

Herpes simplex virus (HSV) infected cells have been detected in tissue culture and human cell specimens by an immunoenzymatic staining method using the fungal enzyme glucose oxidase. Infected cells from culture or human specimens appear as dark blue, brown, or red, depending on the tetrazolium salt used in the disclosing reaction, with virtually no staining of uninfected cells. The specificity and sensitivity of this method and of the more commonly used immunoperoxidase method are comparable, but the immunoglucose oxidase method avoids the problems of nonspecific staining by the endogenous peroxidase present in mucosecretions and inflammatory cells. Staining time can be reduced up to 40% of that necessary for the unlabeled immunoperoxidase procedure without compromising the quality of staining results.

Animals↗