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M Paraskevas

Publications and source records attributed to M Paraskevas.

At least 19 recordsLinked to original sources
PubMed1999

The effect of vaginal microbes on in vivo and in vitro expression of human papillomavirus 16 E6-E7 genes.

Since other viruses can influence expression of human papillomavirus (HPV) 16 E6-E7 genes in vitro, this study addressed whether specific vaginal bacteria do so as well. The vaginal microflora of 18 women with cervical intraepithelial neoplasia (CIN) or normal histology and HPV 16 infection, was evaluated by quantitative culture. Expression of HPV 16 E6-E7 oncogenes was assessed in exfoliated cervical cells by quantitative polymerase chain reaction. HPV 16 expression was also quantitated in CaSki carcinoma cell line cocultured with Bacteroides fragilis or Lactobacillus acidophilus. Isolation of Lactobacillus sp. (p = 0.05) and expression of the E6*II transcript (p = 0.03) were associated with low-grade CIN or normal histology. However, changes in E6-E7 expression were not associated independently with isolation of a specific microorganism. Similarly, expression of HPV 16 E6-E7 oncogenes in vitro was unaltered in the presence of bacteria. These results suggest that vaginal microorganisms are unlikely to alter the natural history of HPV-associated CIN by influencing HPV oncogene expression.

Bacteroides fragilis↗
PubMed1999

Infrared spectroscopy of exfoliated cervical cell specimens. Proceed with caution.

OBJECTIVE: To determine whether diagnostic information may be recovered from the infrared spectra of exfoliated cell specimens by using a novel spectral feature extraction method, in conjunction with linear and quadratic discriminant analysis, for spectral classification. STUDY DESIGN: Over 800 infrared spectra were included in the study, with corresponding clinical diagnoses based upon cytology and, when available, histology reports. Three sets of classification trials were carried out with the aim of distinguishing the spectra corresponding to normal specimens from CIN 1, 2 and 3. For each of these three cases, the procedure was to: (1) develop a set of provisional classification models using only a "training" subset of the spectra, and (2) test each provisional model by its ability to correctly predict the diagnoses on the basis of the remaining spectra. RESULTS: For optimal classification trials, training set classification accuracies were 68% for normal/CIN 1, 73% for normal/CIN 2 and 81% for normal/CIN 3; for the corresponding test sets the classification accuracies were 60%, 60% and 67%, respectively. CONCLUSION: The infrared spectra of exfoliated cervical cells carry information regarding the presence or absence of dysplasia, and that information is recoverable--albeit imperfectly at this stage--from the spectra of "real life" cell preparations.

Algorithms↗
PubMed1996

Contribution of transmission electron microscopy to fine-needle aspiration biopsy diagnosis: comparison of cytology and combined cytology and transmission electron microscopy with final histological diagnosis.

This report evaluates 74 fine-needle aspiration biopsies processed for transmission electron microscopy with subsequent surgical procedure. The specificity of diagnosis obtained by cytology alone was compared to that obtained by cytology and electro microscopy, using histologic diagnosis as the gold standard. When cytology gave a diagnosis of malignancy but could not give tumor category or type, electron microscopy could correctly give both. When cytology could give tumor category but not type, electron microscopy correctly identified type in the majority of cases. When cytology gave tumor category and type, electron microscopy confirmed the diagnosis. Transmission electron microscopy is very helpful when the cytopathologist can diagnose malignancy but cannot give tumor category and/or type. When the cytopathologist is specific in his/her diagnosis, TEM is not as helpful.

Adenocarcinoma↗
PubMed1996

Papillary endothelial hyperplasia of adnexal vasculature.

Papillary endothelial hyperplasia is an exuberant predominantly intravascular endothelial proliferation which may simulate angiosarcoma both clinically and histopathologically. This report describes what, to the best of our knowledge, is a unique case of papillary endothelial hyperplasia within para-ovarian and paratubal veins in relation to a multicystic mesothelial and haemorrhagic ovarian mass. Papillary endothelial hyperplasia should be included in the differential diagnosis of vascular lesions in this site.

Adult↗
PubMed1995

Expression of human papillomavirus type 16 E6-E7 open reading frame varies quantitatively in biopsy tissue from different grades of cervical intraepithelial neoplasia.

The proteins encoded by the human papillomavirus type 16 E6-E7 open reading frame are essential for transformation of the host cell. Two mRNA species, E6*I and E6*II, generated by alternative splicing of a polycistronic pre-mRNA, encode truncated E6 proteins and the E7 protein. Our investigation assessed whether or not the level of expression of E6*I and E6*II varies quantitatively in relation to the grade of cervical intraepithelial neoplasia (CIN). We used a quantitative reverse transcription PCR assay to quantify these transcripts in concurrently collected biopsy tissue and exfoliated cervical cells from 22 women with a normal cervix or various grades of CIN. We evaluated transcription profiles in relation to CIN grade and specimen type. The expression levels of E6*I and E6*II in exfoliated cervical cells did not vary significantly in relation to the grade of CIN. However, expression of E6*II was significantly diminished or absent in biopsy tissue obtained from CIN grade II and III lesions (P = 0.014). Our findings suggest that quantification of E6*I and E6*II expression in biopsy tissue may be more clinically relevant than analysis of exfoliated cells. The identification of distinct patterns of expression in association with low- and high-grade CIN suggests that quantification of E6*I and E6*II expression in biopsy tissue may have prognostic value as an indicator of CIN progression.

Base Sequence↗
PubMed1994

Variability of polymerase chain reaction-based detection of human papillomavirus DNA is associated with the composition of vaginal microbial flora.

The results of repeated human papillomavirus (HPV) DNA testing were compared to changes in cervical pathology and the composition of vaginal microorganisms. A cohort of 19 women with HPV cervical infections in the absence of cervical intraepithelial neoplasia at enrollment was reexamined on average at 7.3-month intervals over a 2-year period. At each follow-up visit, cytological and colposcopic examinations were done and vaginal microorganisms were assessed quantitatively by Gram staining of secretions, and anaerobic and aerobic culture. HPV genotypes 6, 11, 16, and 18 were detected by polymerase chain reaction analysis using DNA isolated from exfoliated cervical cells. The detection of HPV DNA was significantly associated with carriage of Grade II flora (P < 0.001), isolation of Gardnerella vaginalis (P = 0.03), Ureaplasma urealyticum (P = 0.04), Candida albicans (P = 0.01), Bacteroides species (P = 0.01), and overgrowth by anaerobes (P = 0.004). Normal vaginal flora, characterised by the predominance of Lactobacillus species, was significantly associated (P < 0.001) with a negative HPV test. The detection of HPV DNA is associated with the composition of microorganisms present in the vagina at the time of testing.

Adult↗
PubMed1993

Quantification of HPV-16 E6-E7 transcription in cervical intraepithelial neoplasia by reverse transcriptase polymerase chain reaction.

Human papillomavirus type 16 (HPV-16) is associated with neoplastic lesions of the uterine cervix. Viral transforming functions have been localized to the E6-E7 open reading frame (ORF) and this ORF is conserved consistently in cervical intraepithelial neoplasia (CIN). Two mRNAs, generated by alternative splicing, are expressed from the E6-E7 ORF. These are known as E6*I and E6*II, and potentially encode the viral E7 and E6 proteins, respectively. It is believed that the HPV-16 transforming ability is mediated by the E6 and E7 proteins. A quantitative RT-PCR assay, developed by us to characterize the relative expression of E6-E7 spliced transcripts, was applied to exfoliated cervical cells obtained from patients in varying stages of clinically defined CIN and who were infected with HPV-16. The relationship between viral expression, disease stage, oral contraceptive use and age was studied. No association was observed between age or oral contraceptive use and HPV-16 E6-E7 expression. However, when both E6*I and E6*II were detected, a direct correlation was observed between relative proportions of E6*I/E6*II mRNAs greater than 95%/5% and increased disease severity. This study underscores the importance of the relationship between quantities of viral transforming gene transcript and the course of cervical disease. It also suggests that quantification of HPV-16 E6-E7 transcription may be useful as a prognostic tool to identify women who are at increased risk of developing cervical cancer.

Adolescent↗
PubMed1993

Human papillomavirus infection and the size and grade of cervical intraepithelial neoplastic lesions associated with failure of therapy.

OBJECTIVE: This investigation was designed to identify specific risk factors associated with treatment failure for cervical intraepithelial neoplasia. METHOD: A cohort of 436 women was assessed for the presence of cofactors associated with therapy failure. The risk factors included the HPV infection status of the patient, a previous history of genital condyloma and the size of cervical lesions. RESULT: The treatment outcome was not related to the treatment modality (P = 0.058). Thirteen (8.1%) women failed laser therapy, while 15 (5.4%) women failed cryotherapy. While treatment failure occurred only in the presence of HPV infection (P = 0.036), failure was not related to infection by a specific genotype. Therapy failure was associated with treatment for CIN II (RR 4.157) and CIN III (RR 2.053) relative to CIN I and treatment of large lesions (P = 0.014). CONCLUSION: The determination of the relative area occupied by cervical lesions may have prognostic value in identifying women who are at risk for treatment failure.

Adolescent↗
PubMed1993

Detection of human papillomavirus 16 transcription in human prostate tissue.

Previously we demonstrated human papillomavirus type 16 DNA in a high proportion of benign hyperplastic (BPH) and cancerous (CaP) prostate specimens using the polymerase chain reaction (PCR). While these data designate the prostate as a possible reservoir for sexual transmission of HPV, an etiological role for the virus in prostatic neoplasia is uncertain. Since transcription of the E6/E7 genes of HPV 16 is essential for both viral replication and cellular transformation, we sought to assess the transcriptional activity of HPV 16 found in prostate tissues. The E6/E7 viral gene transcripts were identified in 5 of 10 BPH specimens and 3 of 7 CaP specimens known to contain HPV 16 DNA. Expression of the HPV viral genes is not associated preferentially with either BPH or CaP, nor is transcription observed in all samples which contain the viral genome. These findings suggest that the prostate may act as a site for HPV replication, but that HPV is unlikely to be involved in the transformation of prostatic cells.

Base Sequence↗
PubMed1992

Vaginal microbial flora as a cofactor in the pathogenesis of uterine cervical intraepithelial neoplasia.

The vaginal microbial flora of 106 women with histopathologically confirmed cervical intraepithelial neoplasia and 79 women without disease, was evaluated for Gardnerella vaginalis, Trichomonas vaginalis, Candida albicans and other yeasts. Flora morphology was assessed by gram staining of secretions. Cervical cultures were examined for Herpes Simplex virus, Cytomegalovirus and Neisseria gonorrhoeae. Chlamydia trachomatis antigens in cervical secretions were detected by enzyme immunoassay. Human Papillomavirus was identified by koilocytosis in cytologic or histopathologic specimens. Human Papillomavirus infection (P less than 0.00001), vaginal infection with Mycoplasma hominis (P = 0.012) and abnormal vaginal flora (P = 0.006) were significantly associated with CIN, suggesting that CIN may be promoted by vaginal microorganisms in conjunction with human papillomavirus cervical infection.

Adolescent↗
PubMed1992

Glassy cell carcinoma of the cervix: a bimodal treatment strategy.

Glassy cell carcinoma of the cervix is a distinct clinicopathologic entity. This infrequent pathologic subtype is an aggressive biologic tumor associated with a rapid clinical course and poor outcome with conventional treatment modalities in the majority of cases. In a 12-year period from July 1976 to June 1988, 32 cases of glassy cell carcinoma of the cervix were identified. This accounted for 5.3% of all cervical carcinomas. The mean age was 10 years younger than that of other histologic subtypes. A disproportional number of patients with glassy cell carcinoma had malignancies of early clinical stages. The 5-year survival of patients with Stage IB glassy cell carcinoma of the cervix was 45% when treated with primary radical surgery in contrast to 90% for squamous cell and 78% for adenocarcinoma. When bimodal therapy with radical surgery and radical radiotherapy was used, the survival of patients with Stage IB glassy cell carcinoma improved to 87%. Survival of patients with Stage II glassy cell carcinoma of the cervix improved from 50% to 85% with combined radical surgery and radiotherapy. Despite a combination of radical surgery and radiotherapy, complications were minimal.

Adenocarcinoma↗
PubMed1992

Chlamydia trachomatis-associated ectopic pregnancy: serologic and histologic correlates.

Fifty-five women with ectopic pregnancy and 24 undergoing tubal ligation with a segmental resection of the fallopian tube were evaluated for histopathology of the fallopian tube, Chlamydia trachomatis serum antibodies, antibodies to a chlamydial sarkosyl-soluble 57-kDa protein, and for isolation of C. trachomatis. Plasma cell infiltration in the fallopian tube submucosa was identified in 31 (65%) of 48 women with ectopic pregnancies and in 8 (33%) of 24 undergoing tubal ligation (P = .01; odds ratio [OR], 3.6; 95% confidence interval [CI], 1.3-10.3). Plasma cell infiltration was correlated with C. trachomatis seropositivity among women with ectopic pregnancy (P = .005; OR, 7.2; 95% CI, 1.7-31) and among women undergoing tubal ligation (P = .008). Of 21 C. trachomatis-seropositive women with ectopic pregnancies, 19 had antibodies to the 57-kDa antigen compared with 1 of 4 seropositive women having tubal ligation (P = .008). Immune responses to the 57-kDa antigen may be involved in the immunopathogenesis of C. trachomatis-associated ectopic pregnancy.

Adolescent↗
PubMed1990

Effect of the menstrual cycle on detection and typing of human papillomavirus in uterine cervical cells.

We observe fluctuations in human papillomavirus detection and variation in genotyping between sequential cervical cell specimens analyzed by filter in situ hybridization. Furthermore, specimen adequacy for analysis varies. To determine whether these phenomena are correlated with menstrual cycle stage at the time of sampling, we analyzed cervical cell specimens from women with cervical intraepithelial neoplasia. Specimens were categorized on the basis of a 28-day menstrual cycle and were analyzed by hybridization to combined probes for virus types 6 and 11 or types 16 and 18. Specimen adequacy was determined by hybridization to a human Alu I repetitive deoxyribonucleic acid probe. Analysis of data with chi 2 revealed that fluctuations in virus detection and type variation are unrelated to menstrual cycle stage. Specimen adequacy is stage-dependent for women who take oral contraceptives. Whereas specimens can be collected at any time other than the first week of the menstrual cycle, accurate determination of infection status requires multiple assessments.

Cervix Uteri↗
PubMed1989

Comparison of filter in situ deoxyribonucleic acid hybridization with cytologic, colposcopic, and histopathologic examination for detection of human papillomavirus infection in women with cervical intraepithelial neoplasia.

Material from uterine cervical scrapings of 98 women with cervical intraepithelial neoplasia were analyzed by filter in situ hybridization for human papillomavirus infection. Concurrently obtained Papanicolaou smears and colposcopically directed biopsy specimens were also examined for papillomavirus infection. Hybridization was superior to cytologic and colposcopic examinations and was equivalent to histopathologic study for papillomavirus detection. Infection with virus types 6 and/or 11 was associated with milder disease, whereas virus types 16 and/or 18 infection alone or in association with types 6 and/or 11 was associated with more severe disease. Because papillomavirus infection may not be detected by cytologic or colposcopic examination and specific virus types have been documented to be associated with invasive disease, deoxyribonucleic acid hybridization analysis for at least these virus types should be carried out in conjunction with conventional procedures when evaluating women with cervical disease. Filter in situ hybridization is a simple, rapid, noninvasive procedure and has enhanced diagnostic value over conventional procedures by defining infecting virus types.

Cervix Uteri↗
PubMed1989

Hilus cell tumor of the ovary. A clinicopathological analysis of 12 Reinke crystal-positive and nine crystal-negative cases.

The clinical and pathological features of 12 Reinke crystal-positive and nine probable (crystal-negative) hilus cell tumors of the ovary were reviewed. The patients' ages ranged from 32 to 82 years. The initial manifestation was androgenic in 62% of the cases. The levels of testosterone were high (200-2,400 ng/dl) even though the tumors had a mean diameter of only 2.1 cm. All the tumors were centered in the hilus of the ovary, extending for varying distances into the ovarian stroma. They were composed of polyhedral to rounded cells with generally abundant eosinophilic cytoplasm and often showed a perivascular aggregation of nuclei with avascular pooling of cytoplasm or hyalinization of stroma. Fibrinoid changes in the vessels of the tumors were frequently noted. None of the 10 patients for whom follow-up data of 1-17 years were available died of tumor; virilizing symptoms regressed but did not completely disappear in five of the 10 patients after the removal of the tumor.

Adult↗
PubMed1988

Microbial aetiology and diagnostic criteria of postpartum endometritis in Nairobi, Kenya.

Using a protected triple lumen device, Neisseria gonorrhoeae or Chlamydia trachomatis, or both, were isolated from the endometriums of five out of 35 women with clinical postpartum endometritis compared with none of a control group of 30 puerperal women without endometritis (p less than 0.05) in Nairobi, Kenya. These sexually transmitted agents were also found in 12 cervical specimens from women with and three without postpartum endometritis (p = 0.04). Mycoplasma hominis and Ureaplasma urealyticum were equally isolated from the endometrium in both groups. Histology showed plasma cell infiltration in 6/25 patients compared with 1/22 controls (p = 0.06). A history of foul lochia (p less than 0.01) and abdominal pain (p = 0.02) were associated with postpartum endometritis. Sexually transmitted agents appear to be major causes of puerperal upper genital tract infections in Nairobi.

Adult↗