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101.
The origins of human handedness remain unknown. Genetic theories of handedness have received much attention, but some twin studies suggest modest, perhaps negligible genetic effects on handedness. A related question concerning handedness is whether twins have higher rates of left-handedness than do singletons. We studied handedness, with information on forced right-handedness, in a sample of 30 161 subjects aged 18-69 from a questionnaire survey of the older Finnish Twin Cohort. Left-handedness was found to be more common in twins (8.1%) and triplets (7.1%) than in singletons (5.8%), whereas ambidextrousness was more common in triplets (6.4%) than in twins (3.4%) and singletons (3.5%). As in many other studies, males were more likely to be left-handed. Ambidextrous subjects were more likely to become right-handed writers even if not forced to use their right hand. We fit maximum likelihood models to our twin data to estimate the contribution of additive genetic, common environment and unique environmental effects to hand preference. Results, depending on the model, indicate that unique environmental effects account for most observed variance in handedness, both in childhood (92-100%) and adulthood (74-86%). When forced right-handedness was taken into account, estimates of familial effects increased. Concordance for left-handedness in twins is rare, and accordingly, very large samples are needed to detect the familial effects. Our results show that forced-handedness can have an effect on estimates of genetic effects. 相似文献
102.
Castro FA Haimila K Pasanen K Kaasila M Patama T Partanen J Surcel HM Pukkala E Lehtinen M 《International journal of STD & AIDS》2007,18(10):672-679
Cervical cancer (CxCa) is a long-term sequelae caused by persistent human papillomavirus (HPV) infection. Genetic susceptibility to the persistent infection and CxCa is associated with certain human leucocyte antigen (HLA) types. The same susceptibility genes may also determine whether a woman will be protected against the persistent infection and against CxCa by HPV vaccination or not. A systematic review of literature identified following HLAs to be associated with CxCa: A11 (odds ratio [OR] = 1.4, 95% confidence interval [CI] 1.1-2.0); B7 (1.5, 1.1-2.0); B15 (0.6, 0.4-0.8); DR2 (1.2, 1.1-1.4) and DR6 (0.6, 0.5-0.8). In the Caucasian population, HLA-B7 and DR6, and DR2 and B15 antigens showed at least borderline associations. In view of a bone marrow donor registry at the Finnish Red Cross and the Finnish Cancer Registry, we created geographic distribution maps of index HLA frequencies and CxCa incidence in the fertile-aged Finnish population. Increased incidence of CxCa was found in a region of western coastal Finland, where frequency of two CxCa susceptibility genes (HLA-DR2 and B7) was increased, and frequency of one CxCa resistance gene (HLA-B15) was decreased. Whether or not HLA type determines also regional susceptibility to persistent HPV infection, and the success of HPV vaccination in preventing both the persistent infection and CxCa warrants further investigation. 相似文献
103.
Moses SN Houck JM Martin T Hanlon FM Ryan JD Thoma RJ Weisend MP Jackson EM Pekkonen E Tesche CD 《Brain research bulletin》2007,71(5):452-460
Magnetoencephalography (MEG) was used to record the dynamics of amygdala neuronal population activity during fear conditioning in human participants. Activation during conditioning training was compared to habituation and extinction sessions. Conditioned stimuli (CS) were visually presented geometric figures, and unconditioned stimuli (US) were aversive white-noise bursts. The CS+ was paired with the US on 50% of presentations and the CS- was never paired. The precise temporal resolution of MEG allowed us to address the issue of whether the amygdala responds to the onset or offset of the CS+, and/or the expectation of the initiation or offset of the an omitted auditory US. Fear conditioning elicited differential amygdala activation for the unpaired CS+ compared to the CS-, extinction and habituation. This was especially robust in the right hemisphere at CS onset. The strongest peaks of amygdala activity occurred at an average of 270 ms in the right and 306 ms in the left hemisphere following unpaired CS+ onset, and following offset at 21 ms in the left and 161 ms in the right (corresponding to an interval of 108 ms and 248 ms after the anticipated onset of the US, respectively). However, the earliest peaks in this epoch preceded US onset in most subjects. Thus, the activity dynamics suggest that the amygdala both differentially responds to stimuli and anticipates the arrival of stimuli based on prior learning of contingencies. The amygdala also shows stimulus omission-related activation that could potentially provide feedback about experienced stimulus contingencies to modify future responding during learning and extinction. 相似文献
104.
Few studies have examined the effects of both prenatal and postnatal growth on hypertension. We report on hypertension in 2003 people aged 62 years who were randomly selected from the Helsinki birth cohort and examined in a clinic. Their heights and weights had been recorded serially up to age 11 years. A total of 644 had already been diagnosed with hypertension. Compared with normotensive people, they were obese and insulin resistant. At birth they were thin and short, and they gained weight slowly up to age 2 years; thereafter they grew rapidly so that at age 11 years their body size was around the average. The odds ratio associated with each kilogram of birthweight was 0.42 (95% CI: 0.32 to 0.56); with each 10 kg of current weight it was 1.85 (95% CI: 1.66 to 2.05). The blood pressures of another 802 people were classified as hypertensive under current definitions. They were overweight and had an atherogenic lipid profile. At birth they were short, and after birth they grew slowly so that at age 11 years they were short and thin. The odds ratio associated with each kilogram of weight at age 2 years was 0.75 (95% CI: 0.68 to 0.84); with each 10 kg of current weight it was 1.42 (95% CI: 1.28 to 1.57). We conclude that 2 different paths of childhood growth precede the development of hypertension. We suggest that they lead to hypertension through different biological mechanisms and may respond differently to medication. 相似文献
105.
Genetic invalidation of CCK2 receptors abolishes chronic constriction injury (CCI) induced mechanical hypersensitivity in mice. However, housing in environmentally enriched conditions significantly alters the phenotype of CCK2 receptor deficient mice in all major behavioral domains. Furthermore, environmental enrichment itself has been reported to have protective effects in several rodent models of neurological diseases (brain and spinal trauma, ischemic stroke, Alzheimer's disease, etc.). In the present study we reproduced the earlier finding that mice, lacking CCK2 receptors (−/−) are resistant to CCI-induced hypersensitivity. On the other hand, environmental enrichment substantially reduced CCI-induced mechanical hypersensitivity in wild-type (+/+) mice. Nevertheless, the phenotypic differences between wild-type (+/+) and mutant (−/−) mice in mechanical sensitivity before and after CCI-surgery were not eliminated by alternative housing conditions. These observations suggest that environmental enrichment has beneficial effects in neuropathic conditions and reinforce the causal link between CCK2 receptors, mechanical sensitivity and the development of CCI-induced hypersensitivity. 相似文献
106.
Anu-Katriina Pesonen Katri R?ikk?nen Karen Matthews Kati Heinonen Juulia E. Paavonen Jari Lahti Niina Komsi Sakari Lemola Anna-Liisa J?rvenp?? Eero Kajantie Timo Strandberg 《Sleep》2009,32(8):1086-1092
Study Objectives:
We examined whether small body size at birth and prenatal tobacco or alcohol exposure predict poor sleep and more sleep disturbances in children.Design:
An epidemiologic cohort study of 289 eight-year-old children born at term.Measurements and results:
Sleep duration and efficiency were measured by actigraphy for 7 consecutive nights (mean = 7.1, SD = 1.2). We used both continuous measures of poor sleep and binary variables of short sleep and low sleep efficiency ( ≤ 10th percentiles). Parents completed the Sleep Disturbance Scale for Children. Lower birth weight and shorter length at birth were associated with lower sleep efficiency. For every 1-SD decrease in weight and length at birth, the odds for low sleep efficiency increased by 1.7 fold (95% confidence interval [CI]: 1.1 to 2.7) and 2.2 fold (95% CI: 1.3 to 3.7), respectively. For every 1-SD decrease in ponderal index at birth, the risk of parent-reported sleep disorders increased by 1.4 fold (95% CI: 1.0 to 2.0). Moreover, children exposed prenatally to alcohol had a 2.9-fold (95% CI: 1.1 to 7.6) and 3.6-fold (95% CI: 1.3 to 10.0) increased risk for having short sleep and low sleep efficiency, respectively. The associations were not confounded by sex, gestational length, prenatal and perinatal complications, body mass index at 8 years, asthma, allergies, or parental socioeconomic status.Conclusions:
Poor sleep in children may have prenatal origins. Possible mechanisms include alcohol consumption during pregnancy and other conditions associated with small body size at birth.Citation:
Pesonen AK; Röaikköonen K; Matthews K; Heinonen K; Paavonen JE; Lahti J; Komsi N; Lemola S; Jöarvenpöaöa AL; Kajantie E; Strandberg T. Prenatal origins of poor sleep in children. SLEEP 2009;32(8):1086-1092. 相似文献107.
Riikka Laitinen Eero Suihko Kaisa Toukola Joakim Riikonen Kristiina Järvinen 《European journal of pharmaceutics and biopharmaceutics》2009,71(2):271-281
In this study, the dissolution rate of a poorly soluble drug, perphenazine (PPZ) was improved by a solid dispersion technique to permit its usage in intraoral formulations. Dissolution of PPZ (4 mg) in a small liquid volume (3 ml, pH 6.8) within one minute was set as the objective. PVP K30 and PEG 8000 were selected for carriers according to the solubility parameter approach and their 5/1, 1/5 and 1/20 mixtures with PPZ (PPZ/polymer w/w) were prepared by freeze-drying from 0.1 N HCl solutions. The dissolution rate of PPZ was improved with all drug/polymer mixture ratios compared to crystalline or micronized PPZ. A major dissolution rate improvement was seen with 1/5 PPZ/PEG formulation, i.e. PPZ was dissolved completely within one minute. SAXS, DSC and XRPD measurements indicated that solid solutions of amorphous PPZ in amorphous PVP or in partly amorphous PEG were formed. DSC and FTIR studies suggested that PPZ dihydrochloride salt was formed and hydrogen bonding was occurred between PPZ and the polymers. It was concluded that molecular mixing together with salt formation promoted the dissolution of PPZ, especially in the case of the 1/5 PPZ/PEG dispersion, making it a promising candidate for use in intraoral formulations. 相似文献
108.
109.
The aim of this study was to characterize the behavioral effects of systemically administered agmatine in animal models predictive of antidepressant- and anxiolytic-like activity and clarify whether the effects of agmatine depend on the intact serotonergic system. Only the highest dose of agmatine tested (50 mg/kg) decreased immobility of mice in the forced swimming test. The magnitude of the effect was slightly smaller than that of the tricyclic antidepressant imipramine (15 mg/kg). Agmatine did not change the locomotion of mice in the open field. Pretreatment with the tryptophane hydroxylase inhibitor PCPA for 3 days resulted in more than 70% drop in the tissue levels of 5-HT and 5-HIIA but did not counteract the antidepressant-like effect of agmatine. The administration of agmatine did not modify behavior of animals in the light-dark compartment test of anxiety. We conclude that the antidepressant-like effect of agmatine seems not to be mediated by the serotonergic system. We failed to confirm the reported anxiolytic-like activity of agmatine. 相似文献
110.
Rantanen TK Sihvo EI Räsänen JV Salo JA 《The American journal of gastroenterology》2007,102(2):246-253
OBJECTIVES: The population impact of modern treatment on complicated gastroesophageal reflux disease (GERD) is not well understood. Our aim was to determine the current mortality from GERD in Finland and compare this with the use of health resources. METHODS: In this population-based retrospective study, Finland's administrative databases provided figures on the nationwide use of antireflux medication, rate of antireflux surgery, and mortality from GERD. Any deceased person included had classic symptoms as well as objective findings of GERD. RESULTS: After analysis of the medical records of 306 patients, 213 were included. Annual mortality from GERD increased (P < 0.001) from 0.18/100,000 in 1987 to 0.46/100,000 in 2000. During that time, use of H2-blockers and proton pump inhibitors and the annual rate of antireflux surgery increased significantly (P < 0.001). Mortality from antireflux surgery, including fundoplication and gastric and esophageal resection, remained around 1.9/1,000 operations. Of the 213 patients whose cause of death was considered to be GERD, 180 (85%) had received medical treatment, including 4 patients whose death was related to either diagnostic or therapeutic endoscopy. Early complications of antireflux surgery caused 24 (11%) deaths; 9 (4%) were late failures of antireflux surgery. Causes of death in the medical group were hemorrhagic esophagitis (82, 47%), aspiration pneumonia (41, 23%), ulcer perforation (25, 14%), rupture with esophagitis (15, 9%), and stricture (13, 7%). CONCLUSIONS: Regardless of the increased use of health resources, mortality from GERD, especially with medical treatment, rose. Surgery for GERD was also associated with early mortality and usually could not prevent the fatal outcome. 相似文献