Corpus callosum size, reaction time speed and variability in mild cognitive disorders and in a normative sample

Intra-individual variability in reaction time increases with age and with neurological disorders, but the neural correlates of this increased variability remain uncertain. We hypothesized that both faster mean reaction time (RT) and less intra-individual RT variability would be associated with larger corpus callosum (CC) size in older adults, and that these associations would be stronger in adults with mild cognitive disorders. A normative sample (n=432) and a sample with mild cognitive disorders (n=57) were compared on CC area, RT mean and RT variability adjusting for age, sex, education, APOE genotype, smoking, alcohol consumption, grip strength, visual acuity, handedness and lung function. Samples did not differ in CC area or intra-cranial volume. In the normative sample, simple RT (SRT) and choice RT (CRT) were negatively associated with CC area but there were minimal associations between CC area and intra-individual RT variability. In the mild cognitive disorders sample, SRT, CRT and intra-individual variability on the SRT task were associated with CC area. Increased RT variability explained up to 12.7 percent of the variance in CC area in the sample with mild cognitive disorders, but less than 1 percent of the variance in CC area in the normative sample. There were no associations with APOE genotype. We conclude that intra-individual variability is associated with CC area in mild cognitive disorders, but not in normal aging. We propose that biological limits on reserve capacity must occur in mild cognitive disorders that result in stronger brain-behavior relationships being observed.     

Genetic variation in estrogen receptor, C-reactive protein and fibrinogen does not predict the plasma levels of inflammation markers after longterm hormone replacement therapy

Markers of inflammation, such as C-reactive protein (CRP) and fibrinogen, are associated with the risk of atherothrombosis. Plasma levels of these markers of inflammation are affected by hormone replacement therapy (HRT) and modulated by smoking. We studied whether genetic variation in the estrogen receptor- 1 (ESR1), CRP and fibrinogen-beta genes influences the plasma levels of inflammation markers after HRT. Plasma CRP and fibrinogen were measured after five years follow-up in healthy postmenopausal women (per-protocol group) who were randomised to hormone therapy (n=187) or no treatment (n=249). The effect of HRT, smoking and genetic variations in ESR1 (PvuII and XbaI), CRP (1444C/T) and fibrinogen-beta (FGB, -455G/A) were determined. The plasma concentration of CRP was higher in the HRT group than in the control group (2.03 mg/l and 1.41 mg/l, respectively; p < 0.001), while the concentration of fibrinogen was lower in the HRT group than in the control group (3.02 g/l and 3.20 g/l, respectively; p < 0.001), indicating that it is unlikely that inflammation is the common underlying pathway. There was a significant interaction between smoking and HRT on the fibrinogen (p=0.02), but not on the CRP concentration (n.s.). Genetic polymorphisms in ESR1, CRP and fibrinogen were not associated with an effect of HRT on the CRP and fibrinogen plasma levels, and no significant interaction with smoking was observed. In conclusion, higher plasma levels of CRP and lower plasma levels of fibrinogen were observed in women using HRT; however, genetic polymorphisms in ESR1, CRP and FGB were not associated with these effects of HRT.     

Validation of epilepsy diagnoses in the Danish National Hospital Register

PURPOSE: To validate the diagnosis of epilepsy in the Danish National Hospital Register. METHODS: We randomly selected 200 patients registered with epilepsy in the Danish National Hospital Register between 1977 and 2002 and validated the diagnosis according to the guidelines developed by the International League Against Epilepsy. RESULTS: We reviewed the medical records of 188 (94%) persons from 57 departments at 41 hospitals. The epilepsy diagnoses were confirmed in 153 patients, providing a positive predictive value for epilepsy of 81% (95% confidence interval (95% CI): 75-87%). Among the 35 patients who did not fulfill the criteria for epilepsy, 14 were admitted after a single, unprovoked seizure. Among patients registered with epilepsy the positive predictive value of seizure disorder was 89% (95% CI: 83-93%). Among patients classified with epilepsy syndromes, the positive predictive value for syndrome classification was 60% (95% CI: 44-74%) for epilepsy with complex focal seizures and 35% (95% CI: 22-51%) for primary generalized epilepsy. CONCLUSION: The validity of the epilepsy diagnoses in the Danish National Hospital Register has a moderate to high positive predictive value for epilepsy, but a relatively low predictive value for epilepsy syndromes.     

Websites as a mode of delivering mental health information: perceptions from the Australian public

BACKGROUND: Many people with a mental disorder do not access help from mental health services. Internet websites may be a useful tool for disseminating mental health information to those who remain untreated, however little is known about people's perceptions of websites as mental health information sources. The current study examined characteristics that may influence belief in the helpfulness of websites as modes of delivering information about mental health. The study compared belief in the helpfulness websites to two traditional sources (bibliotherapy and health educators). METHODS: A total of 3,998 Australians aged 18 and above were surveyed. Logistic regression was used to explore the factors associated with rating a website, book and health educator as helpful sources of mental health information for a person described as having either depression, depression with suicidal thoughts, early schizophrenia or chronic schizophrenia. Factors investigated were demographics, exposure to mental illness, beliefs about dealing with mental illness alone, and personal and perceived stigmatising attitudes. RESULTS: Considerably more participants rated bibliotherapy and health educators as helpful in comparison to websites. Predictors of rating a website and book as helpful were identical; younger age, belief that it is helpful to deal with mental illness alone and being presented with depression and early schizophrenia vignettes in comparison to chronic schizophrenia. Predictors of rating a health educator as helpful were younger age, less personal stigma and being presented with a depression (without suicidal thoughts) vignette in comparison to chronic schizophrenia. CONCLUSIONS: These findings suggest the need for multiple modes of delivering mental health information. While many people feel that information delivered face-to-face is likely to be helpful, websites and other tools that maintain anonymity may be preferred by those who choose to or find themselves dealing with mental illness alone.     

The same dorsal root ganglion neurons innervate uterus and colon in the rat

The purpose of this study was to determine whether primary sensory neurons that innervate the uterus receive convergent input from the colon. To test this, in the rat, cell bodies of colonic and uterine dorsal root ganglia were retrogradely labeled with fluorescent tracer dyes microinjected into the colon/rectum and bilaterally into the uterine horns. Ganglia were harvested, cryoprotected and cut into 20 microm slices to identify positively stained cells for fluorescent microscopy. Up to 5% of neurons were colon-specific or uterus-specific, and 10-15% of labeled ganglion neurons innervate both viscera in the L1, L2, L6 and S1-S3 levels. These results suggest a novel form of visceral sensory integration in the dorsal root ganglion that may underlie comorbidity of many functional pain syndromes.     

Leptotrichia amnionii found in septic abortion in Denmark

Leptotrichia amnionii was first described in 2002 in the USA. Only few cases have been reported to date, 3 in pregnant women and 2 in non-pregnant women. We present the first case of L. amnionii in Scandinavia, found in a woman with spontaneous second trimester septic abortion.     

Indoor air pollution: a poverty-related cause of mortality among the children of the world

This article reviews the research on the relation between indoor air pollution exposure and acute respiratory infection (ARI) in children in developing countries. ARI is a cause of death globally, causing approximately 19% of all deaths before the age of 5 years, according to a World Health Organization estimate. Indoor air pollution from biomass fuels, which is strongly poverty related, has long been regarded as an important risk factor for ARI morbidity and mortality. The empirical base for this view is comparatively narrow, with few empirical studies in relation to the magnitude of the global public health importance of the problem. Most existing reports consistently indicate that indoor air pollution is indeed a risk factor for ARI, but studies are generally small and use indirect indicators of pollution, such as use of biomass fuel or type of stove. Exposure assessment for indoor air pollution in developing countries is recognized as a major obstacle because of high cost and infrastructural limitations to chemical pollution sampling. Use of proxy indicators without measurement support may increase the risk of both misclassification of exposure and of confounding by other poverty-related factors. The issue of sufficient sample size further underlines the need for decisions to invest in this research field. Areas where further research is needed also include exploring qualitatively options for interventions that are culturally and economically acceptable to local communities.     

Molecular genetic analysis of the calcium sensing receptor gene in patients clinically suspected to have familial hypocalciuric hypercalcemia: phenotypic variation and mutation spectrum in a Danish population

CONTEXT: The autosomal dominantly inherited condition familial hypocalciuric hypercalcemia (FHH) is characterized by elevated plasma calcium levels, relative or absolute hypocalciuria, and normal to moderately elevated plasma PTH. The condition is difficult to distinguish clinically from primary hyperparathyroidism and is caused by inactivating mutations in the calcium sensing receptor (CASR) gene. OBJECTIVE: We sought to define the mutation spectrum of the CASR gene in a Danish FHH population and to establish genotype-phenotype relationships regarding the different mutations. DESIGN AND PARTICIPANTS: A total of 213 subjects clinically suspected to have FHH, and 121 subjects enrolled as part of a family-screening program were studied. Genotype-phenotype relationships were established in 66 mutation-positive index patients and family members. MAIN OUTCOME MEASURES: We determined CASR gene mutations, and correlating levels of plasma calcium (albumin corrected), ionized calcium (pH 7.4), and PTH were measured. RESULTS: We identified 22 different mutations in 39 FHH families. We evaluated data on circulating calcium and PTH for 11 different mutations, representing a spectrum of clinical phenotypes, ranging from calcium concentrations moderately above the upper reference limit, to calcium levels more than 20% above the upper reference limit. Furthermore, the mean plasma PTH concentration was within the normal range in eight of 11 studied mutations, but mild to moderately elevated in families with the mutations p.C582Y, p.C582F, and p.G553R. CONCLUSIONS: The present data add 19 novel mutations to the catalog of inactivating CASR mutations and illustrate a variety of biochemical phenotypes in patients with the molecular genetic diagnosis FHH.     

Small artery structure is an independent predictor of cardiovascular events in essential hypertension

OBJECTIVE: Structural abnormality of resistance arteries is a characteristic pathophysiological phenomenon in essential hypertension and can be assessed in vitro as an increase in the media: lumen ratio (M: L) of isolated small arteries. We have investigated whether M: L is a risk predictor in uncomplicated essential hypertensive patients. Recently, high M: L was demonstrated as a prognostic marker in patients at high cardiovascular risk, including normotensive type 2 diabetic patients. Since diabetes is associated with pressure-independent changes in M: L, the relevance of this finding to essential hypertension has been uncertain. METHODS: We conducted a follow-up survey of 159 essential hypertensive patients, who had previously been submitted to a M: L evaluation while participating in a clinical trial. They composed a homogeneous moderate-risk group, with no concomitant diseases, and represented 1661 years of follow-up. RESULTS: Thirty patients suffered a documented predefined cardiovascular event during follow-up. Increased relative risk (RR) was associated with M: L >or= 0.083 (mean level of the hypertensive cohort), RR = 2.34 [95% confidence interval (CI) 1.11-4.95], and with M: L >or= 0.098 (mean level of a normotensive control group + 2SD), RR = 2.49 (95% CI 1.21-5.11). Both results remained significant (RR = 2.19, 95% CI 1.04-4.64, and RR = 2.20, 95% CI 1.06-4.56, respectively) when adjusted for Heart Score level (10-year mortality risk-estimate, integrating age, gender, systolic blood pressure, cholesterol and smoking). CONCLUSION: Abnormal resistance artery structure independently predicts cardiovascular events in essential hypertensive patients at moderate risk.     

Reproductive costs of the immune response of the autogenous mosquito Culex pipiens molestus against inoculated Dirofilaria immitis

Culex pipiens molestus is an autogenous mosquito, a vector of Dirofilaria immitis in Madeira Island, and it mounts a melanotic encapsulation response when inoculated intrathoracically with D. immitis microfilariae (mf). Because Cx. p. molestus is autogenous, this mosquito is a good model from which to gain a better understand the relationship between oviposition and melanization, independent of the signaling pathways related to blood feeding. The present work assessed the impact follicle growth might have on melanization of intrathoracically inoculated mf. The ovaries from mosquitoes undergoing melanotic encapsulation developed more eggs than those that could not melanize the mf. Possible explanations are discussed in this article.