Karolinska Institutet

About: Karolinska Institutet is a education organization based out in Stockholm, Sweden. It is known for research contribution in the topics: Population & Cancer. The organization has 46212 authors who have published 121142 publications receiving 6008130 citations.

Two different areas within the primary motor cortex of man

Abstract: THE primary motor area (M1) of mammals has long been considered to be structurally and functionally homogeneous1–5. This area corresponds to Brodmann's cytoarchitectural area 4. A few reports showing that arm and hand are doubly represented in M1 of macaque monkeys6,7 and perhaps man8, and that each subarea has separate connections from somatosensory areas, have, with a few exceptions9–12, gone largely unnoticed. Here we show that area 4 in man can be subdivided into areas '4 anterior' (4a) and '4 posterior' (4p) on the basis of both quantitative cytoarchitecture and quantitative distributions of transmitter-binding sites. We also show by positron emission tomography that two representations of the fingers exist, one in area 4a and one in area 4p. Roughness discrimination activated area 4p significantly more than a control condition of self-generated movements. We therefore suggest that the primary motor area is subdivided on the basis of anatomy, neurochemistry and function.

Familial Risk and Heritability of Cancer Among Twins in Nordic Countries.

Abstract: Importance Estimates of familial cancer risk from population-based studies are essential components of cancer risk prediction. Objective To estimate familial risk and heritability of cancer types in a large twin cohort. Design, Setting, and Participants Prospective study of 80 309 monozygotic and 123 382 same-sex dizygotic twin individuals (N = 203 691) within the population-based registers of Denmark, Finland, Norway, and Sweden. Twins were followed up a median of 32 years between 1943 and 2010. There were 50 990 individuals who died of any cause, and 3804 who emigrated and were lost to follow-up. Exposures Shared environmental and heritable risk factors among pairs of twins. Main Outcomes and Measures The main outcome was incident cancer. Time-to-event analyses were used to estimate familial risk (risk of cancer in an individual given a twin’s development of cancer) and heritability (proportion of variance in cancer risk due to interindividual genetic differences) with follow-up via cancer registries. Statistical models adjusted for age and follow-up time, and accounted for censoring and competing risk of death. Results A total of 27 156 incident cancers were diagnosed in 23 980 individuals, translating to a cumulative incidence of 32%. Cancer was diagnosed in both twins among 1383 monozygotic (2766 individuals) and 1933 dizygotic (2866 individuals) pairs. Of these, 38% of monozygotic and 26% of dizygotic pairs were diagnosed with the same cancer type. There was an excess cancer risk in twins whose co-twin was diagnosed with cancer, with estimated cumulative risks that were an absolute 5% (95% CI, 4%-6%) higher in dizygotic (37%; 95% CI, 36%-38%) and an absolute 14% (95% CI, 12%-16%) higher in monozygotic twins (46%; 95% CI, 44%-48%) whose twin also developed cancer compared with the cumulative risk in the overall cohort (32%). For most cancer types, there were significant familial risks and the cumulative risks were higher in monozygotic than dizygotic twins. Heritability of cancer overall was 33% (95% CI, 30%-37%). Significant heritability was observed for the cancer types of skin melanoma (58%; 95% CI, 43%-73%), prostate (57%; 95% CI, 51%-63%), nonmelanoma skin (43%; 95% CI, 26%-59%), ovary (39%; 95% CI, 23%-55%), kidney (38%; 95% CI, 21%-55%), breast (31%; 95% CI, 11%-51%), and corpus uteri (27%; 95% CI, 11%-43%). Conclusions and Relevance In this long-term follow-up study among Nordic twins, there was significant excess familial risk for cancer overall and for specific types of cancer, including prostate, melanoma, breast, ovary, and uterus. This information about hereditary risks of cancers may be helpful in patient education and cancer risk counseling.

Quantification of the influence of cigarette smoking on rheumatoid arthritis: results from a population based case-control study, using incident cases

Abstract: randomly selected from the study base. Self reported smoking habits among cases and controls, and rheumatoid factor status among cases were registered. The incidence of RA in current smokers, ex-smokers, and ever-smokers, respectively, was compared with that of never-smokers. Results: Current smokers, ex-smokers, and ever-smokers of both sexes had an increased risk for sero- positive RA (for ever-smokers the odds ratio was 1.7 (95% confidence interval (95% CI) 1.2 to 2.3) for women, and 1.9 (95% CI 1.0 to 3.5) for men), but not for seronegative RA. The increased risk was only apparent among subjects who had smoked >20 years, was evident at an intensity of smoking of 6-9 cigarettes/day, and remained for up to 10-19 years after smoking cessation. The risk increased with increasing cumulative dose of smoking. Conclusion: Smokers of both sexes have an increased risk of developing seropositive, but not seronegative, RA. The increased risk occurs after a long duration, but merely a moderate intensity, of smoking and may remain for several years after smoking cessation.

Vaginal changes and sexuality in women with a history of cervical cancer.

Abstract: Background In women with cervical cancer, treatment causes changes in vaginal anatomy and function. The effect of these changes on sexual function and the extent, if any, to which they distress women are not known. Methods In 1996 and 1997, we attempted to contact 332 women with a history of early-stage cervical cancer (age range, 26 to 80 years) who had been treated in 1991 and 1992 at the seven departments of gynecological oncology in Sweden and 489 women without a history of cancer (controls) to ask them to answer an anonymous questionnaire about vaginal changes and sexual function. Results We received completed questionnaires from 256 of the women with a history of cervical cancer and 350 of the controls. A total of 167 of 247 women with a history of cancer (68 percent) and 236 of 330 controls (72 percent) reported that they had regular vaginal intercourse. Twenty-six percent of the women who had cancer and 11 percent of the controls reported insufficient vaginal lubrication for sexual intercourse, 26...