A nested case-control study of first-trimester maternal vitamin D status and risk for spontaneous preterm birth

We assessed if first-trimester vitamin D deficiency is more prevalent in women who experienced a spontaneous preterm birth compared with women who delivered at term. We conducted a nested case-control study of pregnant women who had previously given blood for first-trimester combined screening for trisomy 21 and subsequently delivered at a tertiary hospital between November 2004 and July 2009. From an overall cohort of 4225 women, 40 cases of spontaneous preterm birth (≥ 23 (0/7) and ≤ 34 (6/7) weeks) were matched by race/ethnicity with 120 women delivering at term (≥ 37 (0/7) weeks) with uncomplicated pregnancies. Banked maternal serum was used to measure maternal 25-hydroxyvitamin D [25(OH)D]. The prevalence of first-trimester maternal vitamin D deficiency [25(OH)D < 50 nmol/L] was comparable among women who subsequently delivered preterm compared with controls (7.5% versus 6.7%, P = 0.90). The median 25(OH)D level for all subjects was 89 nmol/L (interquartile range, 73 to 106 nmol/L). Seventy-three percent (117/160) of the cohort had sufficient vitamin D levels [25(OH)D ≥ 75 nmol/L]. In a cohort of pregnant women with mostly sufficient levels of first-trimester serum 25(OH)D, vitamin D deficiency was not associated with spontaneous preterm birth.     

Genotoxicity of naturally occurring indole compounds: correlation between covalent DNA binding and other genotoxicity tests

3-Methylindole (3MI), melatonin (Mel), serotonin (Ser), and tryptamine (Tryp) were evaluated in vitro for their potential to induce DNA adducts, DNA strand breaks, chromosomal aberrations (Abs), inhibition of DNA synthesis, and mutations. All compounds produced DNA adducts in calf thymus DNA in the presence of rat liver S9. In cultured rat hepatocytes, all produced DNA adducts but none induced DNA strand breaks. In Chinese hamster ovary cells, 3MI and Mel produced DNA adducts, Abs, and inhibition of DNA synthesis with and without S9, except that Mel without S9 did not form adducts. Ser formed DNA adducts, was an equivocal Abs inducer, and suppressed DNA synthesis. Tryp induced neither adducts nor Abs, but did suppress DNA synthesis with S9. Ser and Tryp were less cytotoxic than 3MI and Mel. Mel, Ser, and Tryp failed to induce mutations in Salmonella and E. coli strains with or without S9. 3MI and Mel produced DNA adducts but not mutations in Salmonella TA100 with S9. 3MI and its metabolite indole 3-carbinol also did not induce mutations in a shuttle vector system in human cells. The lack of correlation between DNA adducts and other genotoxicity endpoints for these indole compounds may be due to the higher sensitivity of the (32)P-postlabeling adduct assay or it may indicate that the indole-DNA adducts per se are not mutagenic and are not able to induce strand breaks or alkali-labile lesions. The indole-induced Abs may result from cytotoxicity and suppression of DNA synthesis with minimal if any contribution from DNA adducts.     

Protection against bacterial superantigen staphylococcal enterotoxin B by passive vaccination

We investigated the ability of two overlapping fragments of staphylococcal enterotoxin B (SEB), which encompass the whole toxin, to induce protection and also examined if passive transfer of chicken anti-SEB antibodies raised against the holotoxin could protect rhesus monkeys against aerosolized SEB. Although both fragments of SEB were highly immunogenic, the fragments failed to protect mice whether they were injected separately or injected together. Passive transfer of antibody generated in chickens (immunoglobulin Y [IgY]) against the whole toxin suppressed cytokine responses and was protective in mice. All rhesus monkeys treated with the IgY specific for SEB up to 4 h after challenge survived lethal SEB aerosol exposure. These findings suggest that large fragments of SEB may not be ideal for productive vaccination, but passive transfer of SEB-specific antibodies protects nonhuman primates against lethal aerosol challenge. Thus, antibodies raised in chickens against the holotoxin may have potential therapeutic value within a therapeutic window of opportunity after SEB encounter.     

Quantitative susceptibility mapping and 23Na imaging‐based in vitro characterization of blood clotting kinetics

Blood clotting is a fundamental biochemical process in post‐hemorrhagic hemostasis. Although the varying appearance of coagulating blood in T₁‐ and T₂‐weighted images is widely used to qualitatively determine bleeding age, the technique permits only a rough discrimination of coagulation stages, and it remains difficult to distinguish acute and chronic hemorrhagic stages because of low T₁‐ and T₂‐weighted signal intensities in both instances. To investigate new biomedical parameters for magnetic resonance imaging‐based characterization of blood clotting kinetics, sodium imaging and quantitative susceptibility mapping (QSM) were compared with conventional T₁‐ and T₂‐weighted imaging, as well as with biochemical hemolysis parameters. For this purpose, a blood‐filled spherical agar phantom was investigated daily for 14 days, as well as after 24 days at 7 T after initial preparation with fresh blood. T₁‐ and T₂‐weighted sequences, a three‐dimensional (3D) gradient echo sequence and a density‐adapted 3D radial projection reconstruction pulse sequence for ²³Na imaging were applied. For hemolysis estimations, free hemoglobin and free potassium concentrations were measured photometrically and with the direct ion‐selective electrode method, respectively, in separate heparinized whole‐blood samples along the same timeline. Initial mean susceptibility was low (0.154 ± 0.020 ppm) and increased steadily during the course of coagulation to reach up to 0.570 ± 0.165 ppm. The highest total sodium (NaT) values (1.02 ± 0.06 arbitrary units) in the clot were observed initially, dropped to 0.69 ± 0.13 arbitrary units after one day and increased again to initial values. Compartmentalized sodium (NaS) showed a similar signal evolution, and the NaS/NaT ratio steadily increased over clot evolution. QSM depicts clot evolution in vitro as a process associated with hemoglobin accumulation and transformation, and enables the differentiation of the acute and chronic coagulation stages. Sodium imaging visualizes clotting independent of susceptibility and seems to correspond to clot integrity. A combination of QSM and sodium imaging may enhance the characterization of hemorrhage.     

The field efficacy of garlic extract against Dermanyssus gallinae in layer farms of Babol,Iran

Dermanyssus gallinae (Acari: Mesostigmata) is the most important hematophagous ectoparasite in layer farms in many countries. The reproduction rate of the parasite is rapid and can be completed in a week under favorable conditions. The parasite has direct and indirect effects on birds. It can also act as a vector for some important pathogens. Many researchers have investigated the effects of essential oils, plant extracts, oriental medicinal plant extracts, and silica against red mite. They can be used as killing agents or repellents. In the present study, the effect of garlic (Allium sativum) extract was investigated for controlling red mite infestation in a layer farm in Babol, North of Iran. Our results showed that the extract was effective and we obtained a 96 % success after two successive sprays.     

The long leg radiograph is a reliable method of assessing alignment when compared to computer-assisted navigation and computer tomography

BackgroundThe mechanical alignment of the knee is an important factor in planning for, and subsequently assessing the success of a knee replacement. It is most commonly measured using a long-leg anteroposterior radiograph (LLR) encompassing the hip, knee and ankle. Other modalities of measuring alignment include computer tomography (CT) and intra-operative computer navigation (Cas). Recent studies comparing LLRs to Cas in measuring alignment have shown significant differences between the two and have hypothesized that Cas is a more accurate modality. This study aims to investigate the accuracy of the above mentioned modalities.MethodologyA prospective study was undertaken comparing alignment as measured by long-leg radiographs and computer tomography to intra-operative navigation measurements in 40 patients undergoing a primary total knee replacement to test this hypothesis. Alignment was measured three times by three observers. Intra- and inter-observer correlation was sought between modalities.ResultsIntra-observer correlation was excellent in all cases (> 0.98) with a coefficient of repeatability < 1.1°. Inter-observer correlation was also excellent measuring > 0.960 using LLRs and > 0.970 using CT with coefficient of repeatability < 2.8°. Inter-modality correlation proved to be higher when comparing LLRs and CT (> 0.893), than when comparing either of these modalities with Cas (> 0.643 and > 0.671 respectively). Pre-operative values had the greatest variability.ConclusionGiven its availability and reduced radiation dose when compared to CT, LLRs should remain the mainstay of measuring the mechanical alignment of the lower limb, especially post-operatively.Level of evidenceII     

Objective stress monitoring based on wearable sensors in everyday settings

Abstract

Monitoring people’s stress levels has become an essential part of behavioural studies for physical and mental illnesses conducted within the biopsychosocial framework. There have been several stress assessment studies in laboratory-based controlled settings. However, the results of these studies do not always translate effectively to an everyday context. The current state of wearable sensor technology allows us to develop systems measuring the physiological signals reflecting stress 24/7 while capturing the context. In this paper, we present a stress monitoring system that provides objective daily stress measurements in everyday settings based on three physiological signals: electrocardiogram (ECG), photoplethysmogram (PPG), and galvanic skin response (GSR) using Shimmer3 ECG, Shimmer3 GSR+, and Empatica E4 wearable sensors. We perform controlled stress assessment experiments on 17 participants in which we successfully detect stress with a 94.55% accuracy for 10-fold cross-validation and an 85.71% accuracy for subject-wise cross-validation. In everyday settings, the system assesses stress with an 81.82% accuracy. We also examine whether motion artefacts affect stress assessment and filter the low-confidence readings to minimise false alarms.     

Evaluating the Prevalence of PTSD among Children and Adolescents after Earthquakes and Floods: a Systematic Review and Meta-Analysis

Psychiatric Quarterly - Our study systematically reviews articles about the prevalence of Post-traumatic Stress Disorder (PTSD) among children and adolescents, aiming to evaluate its prevalence...     

Memory performance related to organic and psychosocial illness attributions in somatoform pain disorder patients

Objective

Somatoform disorders are characterized by patterns of persistent bodily complaints. Organic illness attributions are assumed to represent a central supporting factor in the development and maintenance of somatoform disorders. Using group control design, we aimed to investigate the processing of illness-belief-related word stimuli in somatoform pain disorder patients.

Methods

Organic-related, psychosocial-related, and neutral word stimuli were presented to 14 somatoform pain patients with a predominantly organic illness attribution, 14 somatoform pain patients with a predominantly psychosocial illness attribution, and 14 control participants. Behavioral measures were taken during free recall and recognition tasks.

Results

Our study revealed cognitive impairment in somatoform pain patients with an organic attribution of pain symptoms as compared to somatoform pain patients with a psychosocial attribution and healthy controls in both free recall test and recognition test. However, selective processing of word stimuli was not observed for patient groups.

Conclusion

We conclude that the observed impairment of memory performance in somatoform pain patients with an organic illness attribution may play an important role in the illness behavior of this patient group and ultimately result in the maintenance of symptoms and a more critical clinical outcome.