Failure of MTT as a toxicity testing agent for mesoporous silicon microparticles

In this work, it is shown that the common toxicity indicator, MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide), will fail to predict the toxicity of porous silicon (PSi) microparticles. This is due to the spontaneous redox reactions where the MTT is reduced and the PSi particle surfaces are oxidized simultaneously. MTT was shown to even react with thermally oxidized and carbonized forms of PSi particles, although the treatment did give an enhanced protection against the unwanted reactions as compared to as-anodized PSi particles. The observed levels of cellular viability with the MTT assay were much higher than expected in the presence of Caco-2 cells, even considering the spontaneous reduction of MTT at PSi surfaces. The results indicate that the redox reaction is further enhanced inside living cells. Thus, we recommend that MTT should not be used to test the cytotoxicity of drug formulations containing PSi microparticles. The study also shows that since PSi particles are capable of reducing the MTT, they will also be able to reduce other species as well. This should be taken into account when considering future applications for the porous silicon particles. The completely oxidized SiO2 particles (MCM-41 and SBA-15) were shown to work as expected with the MTT assay and showed no inherent oxidation/reduction.     

Visual fields at school-age in children treated with vigabatrin in infancy

Purpose:   The use of vigabatrin (VGB) as an antiepileptic drug (AED) has been limited by evidence showing that it causes vigabatrin-attributed visual field loss (VAVFL) in at least 20–40% of patients exposed at school age or later. VGB is an effective drug for infantile spasms, but there are no reports on later visual field testing after such treatment. Our aim was to investigate the risk of VAVFL in school-age children who had received VGB in infancy.
Methods:   Visual fields of 16 children treated with VGB for infantile spasms were examined by Goldmann kinetic perimetry at age 6–12 years. Normal fields were defined as the temporal meridian extending to more than 70°, and mild VAVFL between 50 and 70°. Abnormal findings were always confirmed by repeating the test. Exposure data were collected from hospital charts.
Results:   Vigabatrin was started at a mean age of 7.6 (range, 3.2–20.3) months. The mean duration of therapy was 21.0 (9.3–29.8) months and cumulative dose 655 g (209–1,109 g). Eight children were never treated with other AEDs, five received only adrenocorticotropic hormone (ACTH) in addition to VGB, and three children had been treated with other AEDs. Fifteen children had normal visual fields. Mild VAVFL was observed in one child (6%) who had been treated with VGB for 19 months and who received a cumulative dose of 572 g.
Conclusions:   The risk of VAVFL may be lower in children who are treated with VGB in infancy compared to patients who receive VGB at a later age.     

The impact of an educational intervention for elderly care nurses on care recipients' and family relatives' ratings of quality of care: a prospective, controlled intervention study

BACKGROUND: Low competence levels among nursing staff have been associated with lower quality of elderly care. However, interventions aimed at improving nursing staff competence have not always been evaluated for their possible impact on the quality of elderly care. An educational intervention in the form of a workplace "toolbox" was shown to have positive effects on nursing staff competence and work satisfaction. It was therefore of interest to investigate whether the intervention had any effect on residents' and/or their family members' ratings of the quality of elderly care. OBJECTIVES: The aim of this study was to evaluate the possible effects of an educational intervention for nursing staff on care recipients' and their relatives' ratings of the quality of elderly care. DESIGN: The study was a prospective, non-randomized, controlled intervention. PARTICIPANTS AND SETTINGS: Care recipients and their relatives in two elderly care organisations in Sweden. METHODS: Practical instruments and educational materials for improving staff competence and work practices were collated in a workplace "toolbox", which was introduced in the intervention organisation in February of 2003. Care recipients and their relatives' ratings of the quality of care were measured pre and post-intervention by questionnaire and compared to quality ratings in a reference organisation, where no toolbox was introduced. RESULTS: Neither care recipients' nor relatives' ratings of the quality of care changed significantly over time in the intervention organisation. Furthermore, there were no significant interaction effects over time between organisations for quality of care ratings. Methodological weaknesses, such as low response rates, may have influenced results. CONCLUSIONS: The results of this study raise questions regarding the alleged positive association between staff competence and work satisfaction and care recipients' perceptions of the quality of care.     

Splenic artery aneurysm rupture in pregnancy

Rupture of a splenic artery aneurysm, commonly associated with pregnancy is a rare and catastrophic event. We report here a case of a patient in her second pregnancy who presented with a short history of left hypochondriac and epigastric pain, followed by collapse at 32 weeks gestation. Sudden fetal distress lead to emergency caesarean delivery when splenic artery aneurysm rupture was diagnosed. With timely involvement of multidisciplinary personnel both mother and baby survived and had an uneventful recovery.     

Molecular defect of RAPADILINO syndrome expands the phenotype spectrum of RECQL diseases

The RECQL4 helicase gene is a member of the RECQL gene family,mutated in some Rothmund–Thomson syndrome (RTS) patients.Other members of this gene family are BLM mutated in Bloom syndrome,WRN mutated in Werner syndrome and RECQL and RECQL5. All polypeptidesencoded by RECQL genes share a central region of seven helicasedomains. The function of RECQL4 remains unknown, but based onthe domain homology it possesses ATP-dependent DNA helicaseactivity such as BLM and WRN. Rothmund–Thomson, Bloomand Werner syndromes have overlapping clinical features, ofwhich high predisposition to malignancies is the most remarkablefeature. Here we report a fourth syndrome resulting in mutationsin the RECQL genes. RAPADILINO syndrome is an autosomal recessivedisorder characterized by short stature, radial ray defectsand other malformations, as well as infantile diarrhoea, butnot by a significant cancer risk. Four mutations in the RECQL4gene were found in the Finnish patients, the most common mutationrepresenting exon 7 in-frame deletion saving the helicase domainand showing dominant effect over other three nonsense mutations.The tissue expression of Recql4 in mouse well agrees with thetissue symptoms of RAPADILINO. The skeletal malformations inRAPADILINO and RTS patients as well as the high osteosarcomarisk in RTS propose a special role for RECQL4 in bone development. ^* To whom correspondence should be addressed at: Department ofMolecular Medicine, National Public Health Institute, Haartmaninkatu8, 00290 Helsinki, Finland. Tel: +358 947448723; Fax: +358 947448480;Email: marjo.kestila{at}ktl.fi     

A locus for autosomal dominant keratoconus: linkage to 16q22.3-q23.1 in Finnish families

PURPOSE: The estimated world-wide prevalence of keratoconus is 50 to 230 per 100,000 in the general population. Sporadic keratoconus is the leading cause of corneal transplantation surgery in Western countries. Positive family history has been reported in 6% to 8% of patients. The purpose of this study was to map the disease locus in 20 Finnish families with autosomal dominant keratoconus, each family having two or more affected members and with no other associated genetic disease. METHODS: DNA was extracted from blood samples, collected from 42 affected and 34 unaffected family members. Genomic DNA from patients and their parents, was typed for alleles of 292 polymorphic markers. A genome-wide screening was performed to localize the disease gene. Fluorescent markers were amplified by polymerase chain reaction and separated on an automated sequencer. Allele sizes were assigned to each family member, after which LOD scores were calculated. RESULTS: The disease locus was mapped to chromosome 16q, between the markers D16S2624 and D16S3090, with a maximum parametric multipoint LOD score of 4.10 and corresponding nonparametric score of 3.27 (NPL, P = 0.00006). Evidence from 20 families provided support for the linkage, consistent with a single locus for familial autosomal dominant keratoconus without heterogeneity. CONCLUSIONS: This study is the first genome-wide linkage study to map the keratoconus gene. The results suggest that the causative gene in keratoconus is located within the 16q22.3-q23.1 chromosomal region.     

The Relationship between Dietary Habits and Work Engagement among Female Finnish Municipal Employees

Background: Work engagement reflects work-related well-being. It is positively associated with health, life satisfaction, work efficiency, income level, and occupational prospects. However, little is known about the relationship between work engagement and diet. Methods: A cross-sectional study was conducted among female Finnish municipal employees (n = 630) in 2015. Work engagement was assessed using the Utrecht Work Engagement Index. The consumption of healthy and unhealthy food items was determined using a food frequency questionnaire. Sociodemographic factors, health behaviors, depressive and anxiety symptoms were assessed with self-administrated questionnaires. Results: Work engagement had a positive relationship with the daily consumption of healthy food items. This association remained significant even after adjusting for age, education years, financial situation, and physical activity. The frequency of consuming unhealthy food items showed no relationship with work engagement. Anxiety and depressive symptoms decreased linearly with the greater consumption of healthy foods. Conclusion: Frequent consumption of healthy food items is associated with higher work engagement, irrespectively of the consumption of unhealthy nutrients. These results encourage health care professionals to recommend healthy food items instead of forbidding unhealthy food, as well as employers to support healthy dietary habits among employees.     

Cytotoxicity of thermosensitive polymers poly(N-isopropylacrylamide), poly(N-vinylcaprolactam) and amphiphilically modified poly(N-vinylcaprolactam)

Thermosensitive polymers poly(N-isopropylacrylamide) (PNIPAM), poly(N-vinylcaprolactam) (PVCL) and PVCL grafted with amphiphilic poly(ethylene oxide) (PEO) chains (PVCL-graft-C11EO42) were prepared and characterized and their putative cytotoxicity was evaluated. The cytotoxicity of these thermosensitive polymers and their monomers was investigated as a function of polymer concentration, incubation time and incubation temperature by using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) cytotoxicity tests in Caco-2 and Calu-3 cell cultures. Also, the influence of the chain end functionality on toxicity was examined. Viability (MTT) and cellular damage (LDH) of the cells were shown to be dependent on the surface properties of the polymers, hydrophilicity or hydrophobicity. Hydrophilic PVCL and PVCL-graft-C11EO42 were well tolerated at all polymer concentrations (0.1-10.0 mg/ml) after 3 h of incubation at room temperature and at physiological temperature (37 degrees C). The more hydrophobic PNIPAM induced more clear cellular cytotoxicity at 37 degrees C. The monomers N-isopropylacrylamide and vinylcaprolactam and PEO-macromonomer showed dramatically higher cytotoxicity values with respect to the corresponding polymers. Cell damage was directly dependent on concentration, temperature and incubation time.     

In Vitro Effect of Cyclic Adenosine 3′, 5′-Monophosphate (cAMP) on Early Human Ovarian Follicles

PURPOSE: To test the effect of cyclic adenosine 3', 5'-monophosphate (cAMP) on early human ovarian follicles during prolonged culture period. METHODS: Donated ovarian biopsies from 16 women undergoing gynecological laparoscopy were cut into slices and cultured in parallel for 1, 2, or 3 weeks in the presence and the absence of 0.5 mM 8-bromo-cAMP. The developmental stages, sizes, and viability of the follicles were recorded from histological sections of all samples. RESULTS: On day 14, cortical slices cultured with 8-bromo-cAMP showed a significantly higher proportion of secondary follicles (50.0% vs. 20.0%) and a lower proportion of primordial follicles (9.7% vs. 26.7%) when compared with those cultured without 8-bromo-cAMP. On day 21, the proportion of viable follicles in cortical slices with 8-bromo-cAMP treatment was significantly higher than that without 8-bromo-cAMP treatment (79.6% vs. 55.2%). CONCLUSION: CyclicAMP promoted folliculogenesis and follicle survival during 14-21 days' culture of human ovarian cortical slices.     

Linkage to two separate loci in a family with a novel distal myopathy phenotype (MPD3)

We recently described a new type of adult onset distal myopathy (MPD3) with autosomal dominant inheritance. The onset of symptoms is around the age of 30 and the characteristic first symptoms include clumsiness of the hands and stumbling. The thenar and hypothenar muscles are involved at the onset. The disease progressed to the intrinsic muscles of the hands, both anterior and posterior muscle compartments of the lower legs, the forearm muscles, and later to the proximal muscles. Dystrophic changes with rimmed vacuoles were observed in the muscle biopsy. We have performed a genome wide scan here in order to identify the MPD3 locus. Unexpectedly, markers on two distinct chromosomal regions 8p22-q11 and 12q13-q22, provided significant evidence for linkage in this family. Multipoint linkage analyses produced equal maximum multipoint LOD score of 3.01 for both chromosomal regions and haplotype analysis showed a specific haplotype segregating with the disease for both loci. It is thus impossible to distinguish between two loci without additional family material. Two obvious regional candidate genes, encoding muscular proteins became subjects for sequence analyses, the gene for myosin light chain 1 slow-twitch muscle A on 12q13 and the muscle specific exons of ankyrin 1 on 8p11. No mutations were identified in the coding sequence.