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J Paavonen

Publications and source records attributed to J Paavonen.

At least 55 records · Page 3Linked to original sources
PubMed2000

Prerequisites for human papillomavirus vaccine trial: results of feasibility studies.

BACKGROUND AND AIMS: Oncogenic human papillomaviruses (HPVs) are the major cause of cervical cancer and associated cancers. First generation preventive vaccines against HPVs are entering clinical trials. Therefore, it is time to consider prerequisites of field trials in Finland. RESULTS: Incidence of cervical cancer is increasing in young women which is not unexpected since risk taking behavior among young women has also increased. In the developed countries up to 44% of cervical cancer cases are attributable to HPV16 infection alone. However, high risk HPV types other than HPV16 and HPV18 are emerging in the population based on HPV DNA pilot screening studies. Annual attack rates among young women less than 25 years of age is 2.3% for HPV16 infection, and 0.03% for CIN3 invasive cervic cancer. Thus, sample size estimates for HPV vaccine efficacy trial are approximately 1000 when the endpoint is HPV16 infection, and approximately 15000 when the endpoint is >/=CIN3 or worse assuming that the vaccine efficacy is 70%. Both HPV vaccine trial acceptability and compliance rates at routine visits of the general Finnish female population are going to be high based on a pilot study. CONCLUSION: Prerequisites for large scale field trials on HPV vaccination are fulfilled in Finland.

Adult↗
PubMed2000

Chlamydia trachomatis reactive T lymphocytes from upper genital tract tissue specimens.

Chlamydia trachomatis infection is associated with pelvic inflammatory disease (PID) and tubal factor infertility (TFI). We investigated the role of C. trachomatis as a target antigen of endometrial and salpingeal tissue lymphocytes derived from PID and TFI patients. Antigen specificity of the tissue originated T lymphocyte lines (TLL) was tested against C. trachomatis elementary bodies and chlamydial heat shock protein 60 (CHSP60). C. trachomatis antigen stimulated proliferation in two out of eight endometrial TLL derived from PID patients and three out of four TLL derived from TFI patients. All (n = 4) TLL derived from the salpingeal specimens responded to CHSP60 compared with only one out of 12 TLL derived from the endometrial specimens. In-vivo expression of interferon-gamma (IFN-gamma) mRNA revealed that it was present in nine of 13 specimens obtained from PID patients. The dominant activity of type-1 T lymphocytes was confirmed by the in-vitro production of IFN-gamma (median 1007 pg/ml) from all (n = 5) C. trachomatis specific TLL while IL-5 secretion was lower (median 779 pg/ml). In conclusion, C. trachomatis reactive TLL were established from in-vivo activated lymphocytes from the upper genital tract tissue of PID and TFI patients. The reactivity of the salpingeal TLL to CHSP60 provided further evidence that immunoreactivity to CHSP60 is a predominant response in patients with tubal damage.

Adolescent↗
PubMed2000

Expression of sex steroid receptors and Ki-67 in the endometria of menorrhagic women: effects of intrauterine levonorgestrel.

The levonorgestrel-releasing intrauterine system (LNG-IUS) has proven to be the most effective medical treatment in reducing the amount of menstrual blood loss. However, the molecular mechanisms underlying menorrhagia and/or accounting for the therapeutic effect of the LNG-IUS are still obscure. In this study, we used immunohistochemistry to compare the distribution of sex steroid receptors and the proliferation marker Ki-67 in the endometria of women with and without menorrhagia before and after 6 and 12 months of treatment with an LNG-IUS. The study sample included 67 women (aged 35-49 years) who had spontaneous ovulatory cycles. In women with menorrhagia, secretory phase endometrium exhibited more proliferative activity than in women without menorrhagia. No significant differences were found in the immunoreactivity of the oestrogen or progesterone receptors in women either with or without menorrhagia suggesting that, in addition to endocrine hormones, other factors are involved in the regulation of endometrial proliferation and menstrual blood loss. A total of 35 women were treated with LNG-IUS. After 6 months use of an LNG-IUS, the immunoreactivity of both epithelial and stromal progesterone receptors, as well as those of epithelial Ki-67 declined, and no differences were detectable between the women in the menorrhagia and control groups. Breakthrough bleeding remained a problem for nine (26%) LNG-IUS users, with no association with the pre-treatment amount of bleeding. No significant differences were found in the parameters studied between the women with and without breakthrough bleeding 6 months after insertion of an LNG-IUS.

Adult↗
PubMed2000

A randomised controlled trial of vaginal clindamycin for early pregnancy bacterial vaginosis.

OBJECTIVE: To determine whether treatment of bacterial vaginosis (BV) with vaginal clindamycin affects pregnancy outcome. MATERIALS AND METHODS: Mothers with singleton pregnancies and without previous preterm delivery in 17 health centres in Oulu from March 1996 Until March 1998, in whom BV was diagnosed by Gram stain of a vaginal swab at the first antenatal visit (at the 12th gestational week) were randomised at Oulu University Hospital to have a one-week course of vaginal clindamycin, or placebo. A follow up sample of Gram stain was taken two weeks after randomisation and at the 30th gestational weeks. Pregnancy outcome data was obtained from hospital records. Primary outcome was preterm birth, and puerperal infectious morbidity the other outcome measure. RESULTS: During the study period 1956 women were screened, of whom 143 (7.3%) were BV- positive. One hundred and one were randomised. The total preterm birth rate of BV+ women randomised was 9.9% (10/101). Preterm birth occurred in 20.7% (6/29) vs 0% (0/26) according to whether BV persisted or not (P < 0.01). The preterm birth rate was 13.7% (7/51) in the clindamycin group vs 6.0% (3/50) in the placebo group (OR 2.5, 95% CI 0.6-10). BV was cured just after treatment in 17 out of 51 (33%) of the clindamycin- treated patients vs 17 out of 50 (34%) of the placebo- treated patients (OR 1.0, 95% CI 0.4-2.2). There was a difference in puerperal infectious morbidity in patients where BV persisted (31%, 9/29) compared with those in which BV did not persist (7.7%, 1/26) (OR 5.4, 95% CI 1.04-28). Infections were seen in 4/51 (8%) of the clindamycin treated vs 10/50 (20%) of the placebo treated cases, (OR 0.3, 95% CI 0.1-1.2). CONCLUSION: The prevalence of BV was lower than expected in this low risk population, but nevertheless it increased the risk of preterm birth and puerperal infectious morbidity, the risk being highest in cases where BV persisted during pregnancy. Vaginal clindamycin treatment for BV in the first trimester of pregnancy did not appear to reduce the risk of preterm birth or puerperal infections.

Administration, Intravaginal↗
PubMed2000

Evaluation of the Oricult-N dipslide for laboratory diagnosis of vaginal candidiasis.

The Oricult-N semiquantitative dipslide (Orion Diagnostica, Espoo, Finland) was evaluated for the laboratory diagnosis of vaginal candidiasis. It was compared with broth culture (Vagicult; Orion Diagnostica). Oricult-N was positive for 14.5% of 124 symptomatic patients and 12% of 50 asymptomatic controls. The results for broth cultures were 17 and 22%, respectively. Thus, the test group and the control group did not differ significantly by either method. High vaginal yeast counts (>/=10(5) CFU/ml) were detected by Oricult-N in 7% of patients and in 0% of controls, but both groups harbored low numbers of yeasts. An accurate quantitative cutoff point separating a level of yeast associated with infection from vaginal yeast carriage could not be defined in the study. Nevertheless, the easy semiquantitation allowed by the Oricult-N method could be helpful because, especially in low-count carriers of Candida, other potential causes of vaginal symptoms should be considered. The Oricult-N method was technically simple and could be applied in primary health care. Further studies are required, however, before Oricult-N can be recommended as a routine diagnostic tool.

Adult↗
PubMed2000

Attack rates of human papillomavirus type 16 and cervical neoplasia in primiparous women and field trial designs for HPV16 vaccination.

BACKGROUND: Identification of human papillomavirus type 16 (HPV16) as the major risk factor for cervical neoplasia, and mass production of DNA free HPV capsids have paved the way to preventive vaccination trials. Design of such trials requires reliable attack rate data. OBJECTIVE: Determination of (1) HPV16 and (2) cervical neoplasia attack rates in primiparous women. Estimation of actuarial sample sizes for HPV16 vaccination phase IV trials. DESIGN: A longitudinal cohort study. METHODS: Population based Finnish Maternity Cohort (FMC) and Finnish Cancer Registry (FCR) were linked for the identification of two cohorts of primiparous women: (1) a random subsample of the FMC: 1656 women with two pregnancies between 1983-9 or 1990-6 and living in the Helsinki metropolitan area, and (2) all 72,791 primiparous women living in the same area during 1983-94. Attack rate for persistent HPV16 infection (1) was estimated in 1279 seronegative women by proportion of seroconversions between the first and the second pregnancy. Comparable 10 year cumulative incidence rate (CR) of cervical intraepithelial neoplasia grade III and cervical cancer (CIN III+) (2) was estimated based on cases registered at the FCR during 1991-4. RESULTS: The HPV16 attack rates were 13.8% (< 18 years), 7.0% (18-19 years), 2.3% (21 years), 2.4% (23 years), and 4.5% (< 25 years). Number of vaccinees required for a 5 year efficacy trial with persistent HPV16 infection as the end point ranged between 1000 and 3900, assuming 80% power, 90%-70% vaccine efficacy (VE), and misclassification. The CRs of CIN III+ were 0.33% (< 18 years), 0.44% (18-19 years), 0.21% (20-24 years), and 0.28% (< 25 years). Number of vaccinees required for a 10 year efficacy trial with HPV16 positive CIN III+ as the end point was 15,000 assuming 80% power, 90% VE, and 75% aetiological fraction of CIN III+ for HPV16. CONCLUSIONS: The attack rates of HPV16 and CIN III+ identify primiparous women under 25 years of age among target populations for postnatal HPV vaccination at phase II/III trials.

Adolescent↗
PubMed2000

Detection of Chlamydia pneumoniae-reactive T lymphocytes in human atherosclerotic plaques of carotid artery.

Linkage between Chlamydia pneumoniae infection and atherosclerosis has been confirmed in several studies, but the precise role of this organism in the disease process is not known. We investigated the relation and reactivity of T lymphocytes of human carotid plaques to C pneumoniae antigens. Tissue specimens were obtained from 17 patients who underwent carotid endarterectomy. Immunohistological staining and/or in situ hybridization revealed the presence of C pneumoniae in 11 (64%) of the 17 of the cases. Inflammatory infiltration seen in the vessel walls consisted primarily of CD45RO+ T-memory lymphocytes (median 80%, range 50% to 90%), whereas CD20+ B cells and monocytes were in minor proportion. In vivo activated T lymphocytes were propagated from the specimens with interleukin-2, and the antigen specificity of the established T-cell lines (TLLs) was analyzed against C pneumoniae elementary body antigen. TLLs were established from all 17 carotid tissues but none from the control specimens of ascending aorta. C pneumoniae was recognized as a specific T-cell-stimulating antigen in 7 (41%) of 17 cases. Further analyses of the C pneumoniae-reactive TLLs showed that chlamydial 60-kDa heat-shock protein induced specific proliferation in 5 (71%) of 7 cases and revealed 2 haplotype (DRB1*1502 and DQB1*06) binding motifs in human 60-kDa heat-shock protein. C pneumoniae was identified as a specific microbial antigen recognized by 41% of TLLs propagated from in vivo activated plaque T cells. Our results suggests that cell-mediated immunity to C pneumoniae plays a role in the atherosclerotic process and that this response may involve autoimmunity.

Aged↗
PubMed1999

No excess risk of cervical carcinoma among women seropositive for both HPV16 and HPV6/11.

Human papillomavirus (HPV) types 16 and 18 are the major risk factors for cervical carcinoma, whereas HPV types 6 and 11 cause benign genital lesions. We wanted to study the joint effect of simultaneous infections with the oncogenic and non-oncogenic HPV types on risk of subsequent development of cervical carcinoma. A cohort of 530,000 women who had donated blood samples to Nordic serum banks between 1973 and 1994 was followed up by linkage to national cancer registries. We identified 182 prospective cases with invasive cervical carcinoma and selected 538 matched controls at random. HPV 6, 11, 16, 18 and 33 seropositivity was used as a marker for the different HPV infections, and seropositivity for Chlamydia trachomatis and cotinine were used as markers for risk-taking sexual behavior and smoking respectively. The adjusted odds ratio (OR) of cervical squamous-cell carcinoma (SCC) was 2.2 for HPV6/11 among HPV16 seronegatives and 5.5 for HPV16 among HPV6/11 seronegatives. Assuming multiplicative joint effect, the expected OR for seropositivity to both HPV6/11 and HPV16 would have been 12, but the observed OR was 1.0. The antagonistic interaction was statistically significant (p = 0.001) and present also under deterministic considerations of possible misclassification bias. Antagonistic interactions were also detected for combinations of HPV16 and HPV18 and of HPV16 and HPV33. The results are in line with the concept that HPV-specific immunity protects against SCC and support primary prevention of SCC by vaccination against the HPVs.

Adult↗
PubMed1999

Infertility following pelvic inflammatory disease.

OBJECTIVE: To assess the frequency of infertility after pelvic inflammatory disease (PID) and factors important in postinfectious tubal damage in an urban population at high risk for sexually transmitted diseases. METHODS: From a cohort of 213 women with PID documented by laparoscopy and/or endometrial biopsy, 58 women (27% of the initial cohort) were interviewed by phone 2 to 9 years after an index episode of PID. Data regarding the initial history, physical examination, microbiology, laparoscopic, and serologic findings, and data concerning interval contraception, subsequent pregnancy, subsequent infection, and chronic pelvic pain were compared among those with and without infertility at follow up. RESULTS: Nineteen (40%) of the 48 women not using contraception were involuntarily infertile after the index episode of PID. Compared with those who had an interval pregnancy, infertile women were older (P = 0.02), more likely to have a history of infertility prior to the index episode of PID (P = 0.001), and were more likely to have occluded or partially occluded fallopian tubes (P = 0.03), peritubal adhesions (P = 0.007), or perihepatic adhesions (P = 0.02) seen by laparoscopy performed during the index episode. Surprisingly, recovery of Chlamydia trachomatis was negatively related to infertility (P = 0.001), although a similar proportion of both groups had chlamydia immunoglobulin M antibody (40% vs. 31%). Chlamydia heat shock protein was weakly related to infertility (P = 0.08). The isolation of Neisseria gonorrhoeae was not significantly different between groups (53% vs. 57%). CONCLUSIONS: The high rate of postinfection infertility found was probably related to a combination of tubal damage before and during the index episode of PID. Prevention of recurrent PID and better understanding of the pathophysiology of postinfection tubal damage (which may differ between chlamydia and gonorrhea) is needed to develop more effective strategies to reduce permanent tubal damage.

Adolescent↗
PubMed1999

Lack of association between serum antibodies to Chlamydia trachomatis and a history of recurrent pregnancy loss.

OBJECTIVE: To study the relation between recurrent pregnancy loss (RPL) and infection with Chlamydia trachomatis, and to compare the prevalence of antibodies to C. trachomatis in women with primary and secondary RPL. DESIGN: Prospective comparative study. SETTING: University hospital and university student health center. PATIENT(S): Seventy patients with RPL were selected from women attending an RPL outpatient clinic; 40 normal parous women and 94 asymptomatic sexually active women served as controls. INTERVENTION(S): Blood samples were collected during the clinical examinations for RPL. MAIN OUTCOME MEASURE(S): Serum immunoglobulin (Ig) G and IgA antibodies were detected by two independent methods, a recombinant ELISA specific to the genus Chlamydia and microimmunofluorescence testing specific to the species C. trachomatis. RESULT(S): There was no statistically significant difference in the frequencies of IgG or IgA between the women with RPL and the controls. The antibody frequencies were similar in the women with primary and secondary RPL. CONCLUSION(S): The presence of serum antibodies to C. trachomatis is not associated with RPL. Women with primary and secondary RPL do not differ with respect to the prevalence of antichlamydial antibodies. Thus, women with RPL do not benefit from screening for chlamydial IgG or IgA antibodies.

Abortion, Habitual↗
PubMed1999

Plasma cell endometritis is associated with Chlamydia trachomatis infection.

The presence of plasma cells in endometrial tissue has been linked to Chlamydia trachomatis infection. The aim of our work was to determine the strength of the association between C trachomatis infection and plasma cell endometritis. C trachomatis infection was detected by polymerase chain reaction (PCR) or immunohistochemistry in 5 (24%) of 21 endometrial tissue samples with plasma cell endometritis and in 1 (4%) of 28 tissue samples with no evidence of plasma cell endometritis (P < .02). Patients with plasma cell endometritis were also more likely to have symptoms and signs consistent with upper genital tract chlamydial infection; thus there is an association between endometrial C trachomatis infection and the presence of plasma cells in the endometrium. The histopathologic finding of plasma cell endometritis should encourage further examination of the tissue sample for simultaneous chlamydial infection. Plasmid-based polymerase chain reaction and immunohistochemical staining of paraffin-embedded samples are useful methods for detecting C trachomatis in endometrial tissue.

Adult↗
PubMed1999

Menorrhagia and uterine artery blood flow.

Menorrhagia is a significant problem in women of reproductive age. In half of the cases no specific aetiology is known. Vascular factors play a role but remain poorly understood. We chose to study whether any association exists between the flow impedance of uterine arteries and the amount of menstrual blood loss. The study population consisted of 60 spontaneously menstruating 35- to 49-year-old women without endometrial hyperplasia, polyps, or submucous fibroids. The pulsatility index (PI) from uterine arteries, arcuate arteries, and radial arteries was measured by transvaginal colour Doppler. Menstrual blood loss was measured by the alkaline haematin method. A significant inverse correlation was found between uterine artery PI and the amount of menstrual blood loss, suggesting that women with lower uterine flow impedance bleed more. A regression model confirmed that this association was specific and not explained by uterine size, fibroids or any other of the 11 potential confounders included in the model. The correlation between uterine artery PI and amount of menstrual blood loss suggests that vascular factors may be involved in the pathogenesis of menorrhagia.

Adult↗
PubMed1999

Interactions between human papillomavirus and other sexually transmitted agents in the etiology of cervical cancer.

The interplay between human papillomavirus, notably type 16, and HIV in cervical carcinogenesis leads to persistent infection and cervical neoplasia by destruction of the afferent arm (Langerhans cells) of the host immune system. The joint effect takes place at the early stages of squamous intraepithelial lesions and has severe consequences if left untreated. The recent increase of cervical cancer mortality in young women in developed countries may well be a result of the HIV epidemic. Infection with Chlamydia trachomatis is associated with cervical squamous cell carcinoma but not with cervical adenocarcinoma, and the association remains after adjusting for human papillomavirus 16. Joint effects of C. trachomatis and the human papillomaviruses have not been studied at the population level but indirect evidence from epidemiological studies suggests that the interaction might be different (synergistic versus antagonistic) at different stages (cervical intraepithelial neoplasia versus invasive cervical cancer) of cervical carcino-genesis. Concomitant exposure to human papillomaviruses 6 or 11 and human papillomavirus type 16 has not been shown to result in excess risk of cervical squamous cell carcinoma. This antagonistic joint effect was also discovered between human papillomavirus types 18 and 16, as well as 33 and 16. Herpes simplex virus type 2 antibodies are associated with a modest risk of cervical cancer, which is not surprising since the presence of herpes simplex virus antibodies reflects risk-taking sexual behaviour. However, no excess risk remains after adjustment for human papillomavirus type 16, and no interaction between these two viruses has been found in epidemiological studies. Evidence of interaction between human papillomavirus type 16 and the other members of the herpesvirus family is still at an experimental level and difficult to judge. Little progress has been made in the most promising experimental association between the oncogenic human papillomaviruses and adeno-associated viruses. In addition to the well established interaction between human papillomaviruses and HIV, intriguing interactions are emerging between the human papillomaviruses and C. trachomatis, as well as between the different human papillomavirus types.

Journal Article↗
PubMed1999

Chlamydia pneumoniae infection in human monocytes.

Chlamydia pneumoniae infection has been associated with cardiovascular diseases in seroepidemiological studies and by demonstration of the pathogen in atherosclerotic lesions. It has the capacity to infect several cell types, including monocyte-derived macrophages, which play an essential role in the development of atherosclerosis. However, the persistence of C. pneumoniae in mononuclear cells is poorly understood. To study the morphology and biological characteristics of the infection, human peripheral blood monocytes were infected with C. pneumoniae. Freshly isolated monocytes resisted the development of infectious progeny, and confocal and transmission electron microscopy showed that the morphology of the inclusions and chlamydial particles was abnormal. Addition of tryptophan or antibodies against gamma interferon did not diminish the inhibition of C. pneumoniae, suggesting that other factors are involved in the chlamydiostatic activity of the monocytes. Chlamydial mRNA was expressed at least 3 days after infection, however, and a capability for infected monocytes to induce a positive lymphocyte proliferative response was detected for up to 7 days, indicating that C. pneumoniae remains metabolically active in the monocytes in vitro. These results are in accordance with the hypothesis that C. pneumoniae may participate in the maintenance of local immunological response and inflammation via infected monocytes and thus enhance atherosclerosis.

Cells, Cultured↗
PubMed1999

Serological evaluation of herpes simplex virus type 1 and type 2 infections in pregnancy.

OBJECTIVE: Serological evaluation of herpes simplex virus infections during pregnancy. METHODS: 2991 serum samples were obtained during 1st, 2nd, and 3rd trimester from 997 pregnant women. Baculovirus expressed glycoproteins gG1 (HSV-1) and gG2 (HSV-2) were used as antigens in ELISA for HSV-1 and HSV-2 IgG and IgA antibodies. RESULTS: The prevalence of HSV-1 gG1 antibodies was 70% and that of HSV-2 gG2 antibodies 16%. Among susceptible women we found five (0.6%) cases with serological evidence of primary HSV-2 infection during pregnancy. Evidence of active HSV-1 infection was found in nine (0.9%) cases. Decline of HSV-2 gG2 IgG antibody levels during pregnancy was pronounced compared with HSV-1 gG1 IgG antibody levels (p < 0.01); also the proportion of seroreversions was considerably higher among HSV-2 seropositives (25%) than among HSV-1 seropositives (3%) (p < 0.001). CONCLUSIONS: HSV-2 gG2 IgG antibodies were readily distinguished from HSV-1 gG1 IgG antibodies by the glycoprotein gG ELISAs. Serological assays for gG2 antibodies should guard against the decline of specific antibodies during pregnancy.

Adult↗