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8. Maternal antibodies in breast milk protect the child from enterovirus infections

Author

Sadeharju, Karita, Knip, Mikael, Virtanen, Suvi M., Savilahti, Erkki, Tauriainen, Sisko, Koskela, Pentti, Akerblom, Hans K., and Hyoty, Heikki

Subjects
Breast milk -- Nutritional aspects, Enterovirus diseases -- Prevention
Abstract

OBJECTIVE. Enterovirus infections are frequent in infants and may cause severe complications. We set out to assess whether breastfeeding can protect against these infections and whether such an effect is related to maternal antibodies in breast milk or in the peripheral circulation of the infant. METHODS. One hundred fifty infants who were prospectively followed up from birth were monitored for enterovirus infections. The duration of breastfeeding was recorded, and maternal breast milk and blood samples were regularly taken at 3-month intervals for the detection of enterovirus antibodies and RNA. Maternal serum was available from early pregnancy, delivery, and 3 months postpartum. RESULTS. Enterovirus infections were frequent and were diagnosed in 43% of infants before the age of 1 year and in 15% of the mothers during pregnancy. Infants exclusively breastfed for >2 weeks had fewer enterovirus infections by the age of 1 year compared with those exclusively breastfed for [less than or equal to] 2 weeks (0.38 vs 0.59 infections per child). High maternal antibody levels in serum and in breast milk were associated with a reduced frequency of infections. This effect was seen only in those infants breastfed >2 weeks, indicating that breast milk antibodies mediate this effect. Enterovirus RNA was not found in any of the breast milk samples. CONCLUSIONS. These results suggest that breastfeeding has a protective effect against enterovirus infections in infancy. This effect seems to be mediated primarily by maternal antibodies in breast milk. www.pediatrics.org/cgi/doi/10.1542/peds.2006-0780 doi:10.1542/peds.2006-0780 Key Words enterovirus infections, maternal antibodies, autoantibodies, breastfeeding Abbreviations RT-PCR--reverse transcriptase polymerase chain reaction IgG--immunoglobulin G IgA--immunoglobulin A CBV4--coxsackievirus 134 EV11--echovirus 11 EIA--enzyme immunoassay EIU--enzyme immunoassay unit, EARLIER STUDIES HAVE suggested that breastfeeding may protect the infant against infections. Breast milk contains several compounds that may have antimicrobial effects. Maternal antibodies in breast milk were proposed to [...]

Published
2007

10. Epidemiology of HPV 16 and cervical cancer in Finland and the potential impact of vaccination: mathematical modelling analyses

Author

Barnabas, Ruanne V., Laukkanen, Paivi, Koskela, Pentti, Kontula, Osmo, Lehtinen, Matti, and Garnett, Geoff P.

Subjects
Papillomavirus infections -- Care and treatment, Papillomavirus infections -- Prevention, Papillomavirus infections -- Models, Vaccines -- Evaluation
Abstract

ABSTRACT Background Candidate human papillomavirus (HPV) vaccines have demonstrated almost 90%-100% efficacy in preventing persistent, type-specific HPV infection over 18 mo in clinical trials. If these vaccines go on to [...]

Published
2006

13. Human papillomavirus infection as a risk factor for squamous cell carcinoma of the head and neck

Author

Mork, Jon, Lie, A. Kathrine, Glattre, Eystein, Hallmans, Goran, Jellum, Egil, Koskela, Pentti, Moller, Bjorn, Pukkala, Eero, Schiller, John T., Youngman, Linda, Lehtinen, Matti, and Dillner, Joakim

Subjects
Papillomavirus infections -- Health aspects, Head and neck cancer -- Risk factors, Squamous cell carcinoma -- Risk factors
Abstract

Infection with human papillomavirus 16 appears to be a risk factor for squamous cell cancer of the head and neck. This was the conclusion of a study of 292 people with squamous cell head and neck cancer and 1,568 healthy volunteers. This virus has also been linked to cervical cancer.

Published
2001

19. Atopy and Risk of Non-Hodgkin Lymphoma

Author

Melbye, Mads, Smedby, Karin Ekström, Lehtinen, Tuula, Rostgaard, Klaus, Glimelius, Bengt, Munksgaard, Lars, Schöllkopf, Claudia, Sundström, Christer, Chang, Ellen T., Koskela, Pentti, Adami, Hans-Olov, and Hjalgrim, Henrik

Published
2007

22. Association Between High-Sensitive Measurement of C-Reactive Protein and Metabolic Syndrome as Defined by International Diabetes Federation, National Cholesterol Education Program, and World Health Organization Criteria in a Population-Based Cohort of 55-Year-Old Finnish Individuals

Author

HIRSSO, PÄIVI K., TIMONEN, MARKKU J., JOKELAINEN, JARI J., HILTUNEN, LIISA A., LAAKSO, MAURI A., HEDBERG, PIRJO S.M., RUOKONEN, AIMO O., KOSKELA, PENTTI, HÄRKÖNEN, PIRJO K., KEINÄNEN-KIUKAANNIEMI, SIRKKA M., and RAJALA, ULLA M.

Published
2006

43. A discrepancy of Chlamydia trachomatis incidence and prevalence trends in Finland 1983–2003

Author

Lehtinen Matti, Hiltunen-Back Eija, Kaasila Marjo, Lyytikäinen Erika, Tasanen Kaisa, Surcel Heljä-Marja, Koskela Pentti, and Paavonen Jorma

Subjects
Infectious and parasitic diseases, RC109-216
Abstract

Abstract Background Reported rates of Chlamydia trachomatis are on the rise contradicting the declining rates of C. trachomatis associated reproductive sequelae in Western countries. Population based evaluation of the real trend of C. trachomatis infection is important to contemplate prevention efforts. We studied C. trachomatis occurrence during the past 20 years in Finland comparing incidence rate data based on serology and reported C. trachomatis laboratory notifications. Methods A random sample of 7999 women with two consecutive pregnancies within five years was selected from the population of the Finnish Maternity Cohort (FMC) serum bank stratified by calendar year and age. C. trachomatis IgG antibodies were determined by a standard peptide-ELISA. The reported incidence rates of C. trachomatis infections based on case notifications were obtained from the National Registry of Infectious Diseases (NIDR). Results C. trachomatis seroprevalence rates decreased significantly from 1983 to 2003 both in women under 23 years of age (23.3% to 9.2%) and in women between 23–28-years of age (22.2% to 12.6%). However, seroconversion rates increased from 31 per 10000 person years in 1983–85 to 97 per 10000 person years in 2001–2003 (incidence rate ratio 3.2, 95% CI, 1.1–8.7) among the older age group. Seroconversion rate was highest (264) in 1983–1985 in the younger age-group, then declined and subsequently increased again (188) in 2001–2003. The incidence based on seroconversions was in agreement with the reported incidence rates in both age groups. Conclusion C. trachomatis seroprevalence rate decreased during 1983–2003 among fertile-aged women in Finland. During the same time period incidence rates based both on seroconversions and reported laboratory notifications of diagnosed C. trachomatis infections increased. The discrepancy between the C. trachomatis incidence and seroprevalence trends warrants further studies.

Published
2008
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46. Prospective seroepidemiologic study of human papillomavirus infection as a risk factor for invasive cervical cancer

Author

Dillner, Joakim, Lehtinen, Matti, Bjorge, Tone, Luostarinen, Tapio, Youngman, Linda, Jellum, Egil, Koskela, Pentti, Gislefoss, Randi Elin, Hallmans, Goran, Paavonen, Jorma, Sapp, Martin, Schiller, John T., Hakulinen, Timo, Thoresen, Steinar, and Hakama, Matti

Subjects
Papillomavirus infections -- Complications, Cervical cancer -- Risk factors, Health
Abstract

Background: Major risk factors for invasive cervical cancer include infection with human papillomavirus (HPV), infection with other sexually transmitted pathogens (e.g., Chlamydia trachomatis), and smoking. Since exposures to these risk factors can be related, the contribution of any single factor to cervical carcinogenesis has been difficult to assess. We conducted a prospective study to define the role of HPV infection in cervical carcinogenesis, with invasive cancer as an end point. Methods: A nested case-control study within a joint cohort of 700 000 Nordic subjects was performed. The 182 women who developed invasive cervical cancer during a mean follow-up of 5 years were matched with 538 control women on the basis of age and time of enrollment. Serum samples taken at enrollment were analyzed for evidence of tobacco use (i.e., cotinine levels); for antibodies against HPV types 16, 18, and 33; and for antibodies against C trachomatis. Relative risks (RRs) were estimated by use of conditional logistic regression. Results: Presence of antibodies against HPV in serum (seropositivity) was associated with an increased risk of cervical cancer, and adjustment for smoking and for C trachomatis seropositivity did not affect this finding (RR = 2.4; 95% confidence interval [CI] = 1.6-3.7). HPV16 seropositivity was associated primarily with an increased risk of squamous cell carcinoma (RR = 3.2; 95 % CI = 1.7-6.2). In contrast, risk associated with HPV18 seropositivity tended to be higher for cervical adenocarcinoma (RR = 3.4; 95% CI = 0.8-14.9). In populations with a low prevalence of antibodies against C. trachomatis, the HPV16-associated risk of cervical cancer was very high (RR = 11.8; 95% CI = 3.7-37.0); in contrast, in populations with a high prevalence of antibodies against C. trachomatis, no excess risk was found. Conclusion: Past infection with HPV16 increases the risk of invasive cervical squamous cell carcinoma, most clearly seen in populations with a low prevalence of sexually transmitted diseases. [J Natl Cancer Inst 1997; 89:1293-9]

Published
1997

50. Comparing ranking-based collaborative filtering algorithms to a rating-based alternative in recommender systems context

Author

Koskela, Pentti

Subjects
arvosanaperusteinen yhteisöllinen suodatus, sijoitusperusteinen yhteisöllinen suodatus, suosittelujärjestelmät, recommender systems, suodatus, ranking-oriented collaborative filtering, rating-oriented collaborative filtering
Abstract

Suuri sisältövalikoima eri internet palveluissa, kuten verkkokaupoissa, voi aiheuttaa liian suurta informaatiomäärää, mikä heikentää asiakaskokemusta. Suosittelujärjestelmät ovat teknologioita, jotka tukevat asiakkaan päätöksentekoa tarjoamalla ennustettuja suosituksia. On yleistä, että asiakkaalle näytetään lista tuotteista, joista asiakas voisi pitää, esimerkiksi top-10 lista elokuvista. Perinteisesti nämä listat ovat tuotettu käyttäen perinteistä arvosanapohjaista menetelmää, missä tuntemattomille tuotteille ennustetaan arvosana ja järjestetty lista muodostetaan arvosanojen perusteella. Sijoitusperusteinen lähestyminen laskee käyttäjien väliset samankaltaisuudet ja ennustaa järjestetyn listan ilman välivaihetta liittyen arvosanojen laskemiseen. Erilaisia suosittelujärjestelmäalgoritmeja on julkaistu lukuisia eri käyttötarkoituksia varten. Yhteisöllisen suodatuksen kontekstissa sijoitusperusteiset menetelmät ovat yleistyneet järjestettyjen listojen tarkkuuden merkityksen kasvaessa. On olemassa useita hybridivariaatioita missä kaksi tai useampi eri suosittelujärjestelmätyyppi on yhdistetty. Näiden suorituskykyä ei voida verrata tässä tutkielmassa käytettyihin algoritmeihin johtuen niiden erilaisesta toteutustavasta. Tämä tutkielma vertaa kolmea erilaista sijoitusperusteista yhteisöllistä suosittelujärjestelmäalgoritmia keskenään, ja vertailee tuloksia perinteisen arvosanaperusteisen algoritmin kanssa. Tulokset osoittavat parannuksen ennustustarkkuudessa sijoitusperusteista algoritmia käytettäessä, verrattuna arvosanaperusteiseen algoritmiin. Lisäksi, tulokset osoittavat sijoitusperusteisten algoritmien kehityksen parannuksen viime vuosina. Pois lukien tieteelliset julkaisut, missä valitut algoritmit ovat esitelty, en löytänyt tutkielmaa, missä algoritmeja olisi vertailtu keskenään. Tarkastelin tuloksia käyttäen kahta eri arviointimenetelmää, joista Mean Average Precision on vähemmän käytetty tämänkaltaisissa tutkimuksissa. The vast amount of content on internet services, such as e-commerce sites, can cause information overflow, which leads to a bad user experience. Recommender system is technique to support the user’s decision-making by providing predicted suggestions. It is common that user is provided a list of items in user’s preference, e.g. top-10 list of movies. Traditionally, these ranked lists are generated by using rating-based approaches, where ratings are predicted to unknown items which are then calculated to ranked list. Ranking-based approach calculates similarities between users and predicts a ranked list without the middle-step of predicting the ratings first. There is a number of different collaborative filtering (CF) algorithms for different use cases. In a context of CF, ranking-based approaches are becoming more popular as the importance of ranked list accuracy has increased. However, there are several hybrid implementations where two or more different kind of recommender systems are combined, which performance cannot be compared to the algorithms in this thesis due to implementation differences. This thesis will compare three different ranking-based CF algorithms to each other and compare the results with the rating-based CF paradigm. The results will show the prediction accuracy improvement when using ranking-based approaches compared to a rating-based one. In addition, results will also show how much the performance have been improved in ranking-based CF algorithms in the past years. Excluding the research papers where the selected algorithms were introduced, I did not find any research publications where the selected algorithms were compared to each other. I evaluated the results using two different evaluation methods, of which Mean Average Precision is less common in this field of study.

Published
2017

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