Validity of a single-item measure of stress symptoms

OBJECTIVES: The objective of the study was to investigate the content, criterion, and construct validity of a single-item measure of stress symptoms. Such a concise measure would be useful in monitoring stress at work. The criteria for validity were convergence with conceptionally close measures, the plausibility of associations with health and work characteristics, and the power to discriminate between groups. METHODS: Four sets of independent cross-sectional data were used. The first data set, from Finland Post, comprised symptoms of ill health and mental resources (N=1014). The second, from four Nordic countries, included well-known validated scales on exhaustion, mental health, sleep, vitality, and optimism, and therefore the convergence between the measures could be studied (N=1015). The third, from a metal factory, included three indicators of health and four work characteristics (N=773). The fourth, representing the Finnish working population, described group differences in stress symptoms (N=2156) and allowed comparison with a study on emotional exhaustion in the working population. Distributions, correlations, and factor analysis were used for the study. RESULTS: The stress-symptoms item converged with items on psychological symptoms and sleep disturbances and with validated measures of well-being. It had theoretically grounded associations with indicators of health and psychosocial work characteristics, and it discriminated between gender and age groups and industrial branches in accordance with the validated emotional exhaustion scale. CONCLUSIONS: The stress-symptoms item showed satisfactory content, criterion, and construct validity for group-level analysis. It is suggested that the longer scales used to measure psychological stress can be replaced with it in survey research.     

Fluorescence resonance energy transfer reveals a binding site of a photosensitizer for photodynamic therapy

Phthalocyanine (Pc) 4, like many photosensitizers for photodynamic therapy (PDT), localizes to intracellular membranes, especially mitochondria. Pc 4-PDT photodamages Bcl-2 and Bcl-xL, antiapoptotic proteins interacting with the permeability transition pore complex that forms at contact sites between the inner and outer mitochondrial membranes. These complexes and the inner membrane are unique in containing the phospholipid cardiolipin. Nonyl-acridine orange (NAO) is a specific probe of cardiolipin. Here we show evidence for fluorescence resonance energy transfer from NAO to Pc 4, defining a binding site for the photosensitizer. This observation establishes an innovative tool for exploring the localization of other photosensitizers and additional fluorescent, mitochondrion-localizing drugs having appropriate spectral properties.     

Similar effect of revascularization on technetium-99m( )sestamibi and 15-(p-iodophenyl)pentadecanoic acid uptake in myocardial infarction patients.

To study its usefulness as a tracer for assessment of the perfusion and viability of myocardium, 15-(p-iodophenyl)pentadecanoic acid (IPPA) was compared with technetium-99m sestamibi (MIBI). Dual-tracer single-photon emission tomography rest imaging was performed no more than 2 months before and 3 months after coronary artery bypass grafting in 28 patients with previous anterior (n=13) or inferior (n=15) infarction. The size of MIBI and IPPA defects decreased from 14%+/-12% and 13%+/-9% to 10%+/-11% and 9%+/-7%, respectively (P<0.001 for both). The MIBI uptake increased in the infarct zones from 35%+/-11% to 43%+/-8% (P<0.001), and in the peri-infarct zones from 50%+/-11% to 55%+/-10% (P<0.05). The IPPA uptake increased in the infarct zones from 37%+/-11% to 44%+/-13% (P<0.001), and in the peri-infarct zones from 51%+/-11% to 57%+/-12% (P<0.05). In nine patients with improved regional echocardiographic wall motion score after bypass surgery, the pre-operative uptake values of both MIBI and IPPA in the infarct and peri-infarct zones were on average slightly but not significantly higher than in 19 patients with no observed improvement in regional wall motion score. In patients with improved regional wall motion, the MIBI scans and the IPPA scans showed (non-significant) decreases in defect size and increases in infarct and peri-infarct zone uptake after bypass surgery. Similar (in some cases significant) changes were observed in the patients without improvement in wall motion. Thus IPPA and MIBI provided similar information about perfusion and viability in pre- and postoperative evaluation of patients with clinically evident myocardial infarction and with normal global ejection fraction. Regardless of the tracer used, the resolution capability of the dual-tracer method with a rest imaging protocol was not sufficient to differentiate viable from non-viable infarction defects in unselected individual patients with a normal ejection fraction.     

Detailed radiosynthesis of [18F]mG4P027 as a positron emission tomography radiotracer for mGluR4

We report here the detailed radiosynthesis of [¹⁸F] mG4P027 , a metabotropic glutamate receptor 4 (mGluR4) PET radiotracer, which showed superior properties to the currently reported mGluR4 radiotracers. The radiosynthesis in the automated system has been challenging, therefore we disclose here the major limiting factors for the synthesis via step-by-step examination. And we hope this thorough study will help its automation for human use in the future.     

Invasive group B streptococcal infections in Finland: a population-based study

We analyzed surveillance data on group B streptococcus (GBS) infection in Finland from 1995 to 2000 and reviewed neonatal cases of early-onset GBS infection in selected hospitals in 1999 to 2000. From 1995 to 2000, 853 cases were reported (annual incidence 2.2-3.0/100,000 population). We found 32-38 neonatal cases of early-onset GBS disease per year (annual incidence 0.6-0.7/1,000 live births). In five hospitals, 35% of 26 neonatal cases of early-onset GBS infection had at least one risk factor: prolonged rupture of membranes, preterm delivery, or intrapartum fever. Five of eight mothers screened for GBS were colonized. In one case, disease developed despite intrapartum chemoprophylaxis. Although the incidence of early-onset GBS disease in Finland is relatively low, some geographic variation exists, and current prevention practices are suboptimal. Establishing national guidelines to prevent perinatal GBS is likely to reduce the incidence of the disease.     

Does vitamin D supplementation in infancy reduce the risk of pre-eclampsia?

Vitamin D has been suggested to affect the balance between T helper (Th1) and (Th2) type cytokines by favouring Th2 domination. We investigated the association between infant vitamin D supplementation and later pre-eclampsia, a disorder suggested to be dominated by Th1 response. We used data on 2969 women born in the Northern Finland Birth Cohort 1966 of whom 68 (2.3%) had pre-eclampsia in their first pregnancy. Risk of pre-eclampsia was halved (OR 0.49, 95% confidence interval (CI) 0.26-0.92) in participants who had received vitamin D supplementation regularly during the first year of life and this association was not affected by adjustment for own birth order, birth weight, gestational age, social class in 1966 and hospitalizations or pregnancy-induced hypertension of their mothers. Together with earlier observations on a reduced risk of type 1 diabetes after vitamin D supplementation, these data suggest that vitamin D intake in infancy may affect long-term programming of the immune response pattern.     

High birth weight, asthma and atopy at the age of 16 yr

The association between high birth weight and asthma has been suggested. The Northern Finland Birth Cohort 1986, a longitudinal cohort originally including 9479 participants, has been followed up since birth until the age of 16 yr. Using the data of this study, we analyzed the association of high birth weight with asthma and atopic sensitization at the age of 16 yr. The analysis included the 5995 subjects with complete skin prick test data and the 5500 subjects with data on doctor-diagnosed asthma (written questionnaire) at the age of 16 yr. Atopy was defined as at least one positive skin prick test reaction, which definition was also used to separate atopic and non-atopic asthma. There was a significant association between high birth weight (>4510 g) and asthma among the atopic subjects (OR 2.40, 95% CI 1.33–4.32). When looking at atopy, the highest risk was observed among the subjects with highest birth weight category (>4510 g) (OR 1.44, 95% CI 1.05–1.97) and the adjacent (4200–4500 g) birth weight category (OR 1.24, 95% CI 1.01–1.53), when compared with the reference category (2500–3340 g). Our results support the notion that high birth weight is associated with an increased risk of asthma and suggest that the association is mostly explained by an increased risk of atopy. The biological mechanisms behind the associations are unknown, but they could be related to obesity.