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J T Bryan

Publications and source records attributed to J T Bryan.

27 records · Page 2Linked to original sources
PubMed1996

Human papillomavirus detection by hybrid capture in paired cervicovaginal lavage and cervical biopsy specimens.

Infection of the uterine cervix with human papillomavirus (HPV) is associated with dysplastic lesions that may progress to malignancy. Certain HPV types are associated with higher risk of cervical cancer than other genital HPVs. The goal of this study was to determine if cells obtained by cervicovaginal lavage contain similar HPV types as paired cervical biopsy in women referred because of abnormal cervical cytology. Thirty-four paired lavage and biopsy samples were analyzed for HPV DNA by hybrid capture, using "low risk" (HPV types 6. 11, and related types and "high risk" group (HPV types 16, 18, and related types) HPV. HPV was detected in 24 lavage samples and 18 biopsies. High risk types were predominant. In 14 of 18 HPV-positive biopsies, the paired lavage was also positive for the same HPV group. Four biopsies were HPV-positive at low levels, and the paired lavage was HPV-negative. The mean viral copy numbers of the biopsies from patients with positive and negative lavage samples were 2.7 and 0.1, respectively (P = .02). Ten low level HPV infections were detected by lavage that were not detected by biopsy. HPV detection by hybrid capture in cells obtained by cervicovaginal lavage reflects the results of HPV testing in cervical biopsies.

Cell Biology↗
PubMed1995

Human papillomavirus type 11 E1--E4 and L1 proteins colocalize in the mouse xenograft system at multiple time points.

The most abundant viral mRNA species in HPV 11-infected tissue consists of two exons, joining a segment of open reading frame (ORF) E1 to ORF E4, potentially encoding the E1--E4 protein. The L1 ORF encodes the major capsid protein of HPV. Our previous studies demonstrated colocalization of the HPV 11 E1--E4 and L1 proteins within the same cells of HPV 11-infected human foreskin implants grown in athymic mice (the mouse xenograft system) and removed 12 weeks after implantation. Prior studies have demonstrated E1--E4 transcripts early in infection and throughout the HPV 11-infected epithelium, while L1 transcripts are detected later, and in a subset of E1--E4 mRNA-positive differentiated epithelial cells. Therefore, E1--E4 protein may be produced at an earlier time point or in less differentiated cells than the L1 protein. To study these questions, athymic mice were implanted with HPV 11-infected human foreskin fragments. Mice were sacrificed at 1-week intervals beginning 2 weeks after implantation of tissue. The E1--E4 and L1 proteins colocalized to the same differentiated epithelial cells or to tight clusters of cells in differentiated epithelial layers of HPV 11-infected implants. The E1--E4 and L1 proteins were first detected 4 weeks after implantation. E1--E4 protein was detected in the region of the cell membrane and cytoplasm, and never in the nucleus. L1 protein was only detected in the nucleus. Both proteins were detected in implants containing high viral copy numbers. No specific histologic changes were uniformly associated with detection of these proteins. The tight coupling of the E1-E4 and L1 proteins at multiple time points suggests that expression of both proteins is necessary to complete the virus life cycle.

Animals↗
PubMed1994

Detection of multiple human papillomavirus types in condylomata acuminata from immunosuppressed patients.

Using the hybrid capture method, condylomata acuminata from healthy patients (controls) and patients with altered cell-mediated immunity were analyzed for multiple human papillomavirus (HPV) DNA: 82.9% and 38.0% of lesions from 41 controls and 21 patients, respectively, were HPV DNA-positive only with probes for low-risk HPV types (P = .00035). Using probes for both low- and high-risk HPV types, 16.3% and 52.3% of lesions from 43 controls and 21 patients, respectively, were positive for both probes (P = .0038). Evidence of multiple HPV types was also found by Southern blot and in situ hybridization studies. The mean HPV copy number detected by either probe did not differ significantly among patient groups. Using sensitive techniques, such as hybrid capture, multiple HPV types, including those associated with genital malignancy, can be detected in condylomata acuminata. Serial biopsies demonstrate the dynamic nature of genital HPV infection and that changes in the predominant HPV types may be reflected in tissue pathology.

Biopsy↗
PubMed1993

Detection of human papillomavirus L1 protein in condylomata acuminata from adults with defects in cell-mediated immunity.

Immunohistochemical assays for human papillomavirus (HPV) L1 protein, using antiserum directed against the L1 major capsid protein of bovine papillomavirus (anti-BPV serum), were performed on 101 condylomata acuminata biopsy samples from 47 men (40 of whom had intact cell mediated immunity [CMI], and 7 with conditions known to cause CMI defects), and 54 women (48 with normal CMI, and 6 with CMI defects). L1 protein was detected in 28% of all biopsies, including 20.5% of samples from patients with normal CMI and 76.9% of patients with CMI defects (P = .00002). For both males and females, L1 protein was detected significantly more often in samples from patients with CMI defects than those with normal CMI. Immunohistochemical assays of HPV 11-infected human foreskin implants grown in athymic mice were performed to optimize the conditions of the assay. Three dilutions of anti-BPV serum or preimmune rabbit serum were used. A 1:500 dilution provided readily interpretable results, while preimmune serum at this dilution did not stain to any significant degree. However, at 1:10 and 1:100 dilution, both the anti-BPV serum and preimmune serum caused an unacceptable amount of nuclear staining, making results uninterpretable. Defects in CMI may allow active viral particle assembly at an increased rate, as judged by detection of L1 protein in condylomata acuminata from these patients.

Capsid↗
PubMed1993

Analysis of human papillomavirus types in exophytic condylomata acuminata by hybrid capture and Southern blot techniques.

Exophytic condylomata acuminata of the external genitalia of 40 patients were analyzed for human papillomavirus (HPV) DNA by the Southern blot and hybrid capture methods. All lesions were initially analyzed by the Southern blot method by using a mixture of HPV type 6, 11, 16, and 18 whole genomic probes. Southern blots demonstrated characteristic PstI restriction patterns of HPV type 6, 11, or 16 in all but one lesion. HPV 6 subtypes accounted for 28 of 39 HPV-positive lesions. Twenty-seven of these 28 lesions contained HPV type 6a, and 1 lesion contained HPV type 6c. Eight lesions contained HPV type 11 and three contained HPV type 16. Two of the three condylomata acuminata containing HPV type 16 were obtained from solid-organ transplant recipients receiving immunosuppressive medications. The third lesion containing HPV type 16 was a typical exophytic condyloma acuminatum from a woman with previously resected vulvar carcinoma. The hybrid capture assay detected HPV DNAs in all lesions except the Southern blot-negative lesion. Twenty-five lesions were positive for the A probe only (HPV types 6 and 11 and related types). All of these lesions were found to contain HPV type 6 or 11 sequences in the Southern blot assay. The remaining 14 lesions were positive for both the A probe and the B probe (HPV types 16 and 18 and related types). The strongest signal in these 14 lesions by the hybrid capture assay was consistent with the result of the Southern blot assay in all but one case. We conclude that (i) HPV type 6a is the most common type found in these lesions, (ii) HPV type 16 may be present more often in exophytic condylomata acuminata from immunosuppressed individuals, (iii) hybrid capture is a useful tool for documenting the presence of HPV sequences in DNAs from exophytic condylomata acuminata, and (iv) in samples containing multiple HPV types, hybrid capture allows detection of minority HPV types.

Blotting, Southern↗
PubMed1992

Factors associated with detection of human papillomavirus E4 and L1 proteins in condylomata acuminata.

The E4 and L1 gene products of human papillomavirus (HPV) types 6 and 11 are detected in variable amounts in condylomata acuminata. To study factors associated with detection of these proteins, biopsy specimens containing HPV-6 or -11 were analyzed for E4 protein, L1 protein, and HPV copy number. Seventeen of 50 women biopsied were pregnant. Nine men were also biopsied. Both the E4 and L1 proteins were found more frequently in lesions from pregnant women than from nonpregnant women or men. Both proteins were more often detected in lesions from women than from men. E4 gene products were more often detected in lesions in which L1 protein was detected and a higher HPV copy number was present. Detection of E4 gene products correlates with the detection of L1 protein in condylomata acuminata caused by HPV-6 or -11.

Adult↗
PubMed1976

Stability of aqueous solutions of mibolerone.

The kinetics and mechanism of degradation of mibolerone were studied in aqueous buffered solutions in the pH range of 1-8 at 67.5 degrees. Mibolerone showed maximum stability between pH 5.5 and 6.4. At pH 1-2, the major degradative pathway was dehydration followed by migration of the 18-methyl group to form 7alpha,17,17-trimethylgona-4,13-dien-3-one. While there was only one degradation product at pH 1-2, the degradation at pH 7-8 was complex. As many as 12 degradation products were detected by GLC. Mass spectral data indicated that the majority of these products were either oxidation products or isomers. At pH 7.6, the apparent first-order rate constants exhibited marked dependency on buffer concentration. Incorporation of a sequestering agent into the solutions eliminated this dependency, suggesting that trace metal impurities from the buffer reagents were catalyzing the degradation. This was confirmed by degradation studies of solutions in water for injection containing 5 ppm of trace metal ions. Sn+2, Cu"2, and Fe+2 accelerated the degradation, with Fe+2 having the most catalytic effect. The temperature dependence of the rate of degradation was studied in 0.05 M phosphate buffer at pH 6.4. The activation energy was 19.6 +/- 1.63 kcal/mole.

Anabolic Agents↗
PubMedDate not supplied

Detection of human papillomavirus L1 protein in condylomata acuminata from various anatomical sites.

BACKGROUND AND OBJECTIVES: Though human papillomavirus (HPV) DNA can be detected in the majority of condylomata acuminata, the major capsid protein of HPV (L1 protein) can be detected in only 10% to 50% of lesions in immunohistochemical assays. GOAL OF STUDY: To evaluate the association between anatomic location of genital HPV infections and the ability to detect HPV L1 protein. METHODS: Condylomata acuminata from 49 male and 51 female patients were evaluated for L1 protein by immunohistochemistry. Thirty of these lesions were vulvar; 20 were cervical; 1 was vaginal; 45 were penile; and 4 were perianal. A quantitative analysis of L1-positive nuclei in the lesions was performed. RESULTS: L1 protein was detected in 20 (20%) of all lesions. L1 protein was detected in seven (35%) of the cervical lesions compared to nine (12%) of exophytic condylomata acuminata of males and females (P = 0.038). A statistically significant difference was noted between cervical and exophytic condylomata acuminata lesions (46.6 vs. 7.8) (P = 0.0006). No association between oral contraceptive use and L1 protein detection was found. CONCLUSIONS: The major capsid protein of HPV can be detected in condylomata acuminata of the uterine cervix more often, and in higher quantities, than in lesions of the vulva or penis. Further studies are needed to assess the effects of sex hormones and the anatomic location of the infection as they relate to transmission of HPV.

Biopsy↗