Disordered directional brain network interactions during learning dynamics in schizophrenia revealed by multivariate autoregressive models

Directional network interactions underpin normative brain function in key domains including associative learning. Schizophrenia (SCZ) is characterized by altered learning dynamics, yet dysfunctional directional functional connectivity (dFC) evoked during learning is rarely assessed. Here, nonlinear learning dynamics were induced using a paradigm alternating between conditions (Encoding and Retrieval). Evoked fMRI time series data were modeled using multivariate autoregressive (MVAR) models, to discover dysfunctional direction interactions between brain network constituents during learning stages (Early vs. Late), and conditions. A functionally derived subnetwork of coactivated (healthy controls [HC] ∩ SCZ] nodes was identified. MVAR models quantified directional interactions between pairs of nodes, and coefficients were evaluated for intergroup differences (HC ≠ SCZ). In exploratory analyses, we quantified statistical effects of neuroleptic dosage on performance and MVAR measures. During Early Encoding, SCZ showed reduced dFC within a frontal–hippocampal–fusiform network, though during Late Encoding reduced dFC was associated with pathways toward the dorsolateral prefrontal cortex (dlPFC). During Early Retrieval, SCZ showed increased dFC in pathways to and from the dorsal anterior cingulate cortex, though during Late Retrieval, patients showed increased dFC in pathways toward the dlPFC, but decreased dFC in pathways from the dlPFC. These discoveries constitute novel extensions of our understanding of task‐evoked dysconnection in schizophrenia and motivate understanding of the directional aspect of the dysconnection in schizophrenia. Disordered directionality should be investigated using computational psychiatric approaches that complement the MVAR method used in our work.     

Children's lived experiences of hematopoietic stem cell transplantation

Although hematopoietic stem cell transplantation is a valuable treatment in many life‐threatening pediatric disorders, a large number of children who receive hematopoietic stem cell transplantation are faced with a variety of physical and psychological problems throughout this process. In this study, we explored the lived experiences of these children during their treatment to provide a better understanding of their main concerns, emotions, and expectations. The participants were six children, aged between 6 and 17 years, who underwent hematopoietic stem cell transplantation. Data were collected through individual, in‐depth, and semistructured interviews. Using interpretive phenomenological analysis, the findings revealed that the children experienced “transplantation rejoicing” in this “difficult passage”, which was associated with “deepening of family ties”. Awareness of these experiences, feelings, and concerns can help in the development of more professional interventions to provide children with holistic care during their hospitalization.     

The efficacy of wet-cupping in the treatment of tension and migraine headache

Wet-cupping is an ancient medical technique still used in several contemporary societies, but little empirical study has been devoted to test its efficacy to treat tension and migraine headache. Using a pre-post research design, 70 patients with chronic tension or migraine headache were treated with wet-cupping. Three primary outcome measures were considered at the baseline and 3 months following treatment: headache severity, days of headache per month, and use of medication. Results suggest that, compared to the baseline, mean headache severity decreased by 66% following wet-cupping treatment. Treated patients also experienced the equivalent of 12.6 fewer days of headache per month. We conclude that wet-cupping leads to clinical relevant benefits for primary care patients with headache. Possible mechanisms of wet-cupping's efficacy, as well as directions for future research are discussed.     

Bone mineral density in Iranian patients with inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) are at increased risk of developing osteopenia and osteoporosis. The aim of the study was to investigate the prevalence of decreased bone density and related risk factors in Iranian IBD patients. A total of 126 ulcerative colitis (UC) and 39 Crohn’s disease (CD) patients were enrolled. Dual-energy x-ray absorptiometry technique was used to measure bone density, and blood samples were obtained to measure biochemical markers. To find predictive variables for bone mineral density (BMD), stepwise regression analysis was carried out. A total of 53 IBD patients (32.1%) had diminished bone mineral density at either lumbar spine (L1–L4) or femoral neck. Of these, 9 (5.4%) had osteoporosis; however, 44 (26.7%) were osteopenic. Femoral neck bone density was significantly decreased among CD patients (p<0.04). There was no significant difference in BMD between men and women. We have found significant differences in BMD T scores at lumbar L1–L4, L2–L4, and femoral neck in corticosteroid ever-users (p<0.002, p<0.001, p<0.003, respectively). There was no significant difference in biochemical markers between UC and CD patients, except that more CD patients were hypocalcemic (p<0.001). Stepwise regression analysis has revealed lumbar spine T score was predicted by age (p<0.0001), corticosteroid use (p<0.002), and body mass index (BMI) (p<0.005); however, femoral neck was predicted by age (p<0.0001), BMI (p<0.0001), smoking (p<0.009), and corticosteroid use (p<0.028). Low bone density in Iranian UC and CD patients is in accordance with Western societies. Treatment with corticosteroid has increased this possibility in both groups. Corticosteroid use, age, smoking, and BMI are predictive factors for low bone density.     

Evaluation the nonlinear response function of a 3 x 3 in NaI scintillation detector for PGNAA applications.

Response functions of the 3 x 3 in NaI detector, which is mainly used in PGNAA applications, have been calculated by using MCNP-4C code. Calculated results are compared with measured data by using standard gamma-ray sources and prompt gamma-rays from pure element samples to check their accuracy. Prompt gamma-rays from pure element samples were used for this determination in the range from 1.942 to 10.829 MeV by use of (241)Am-Be neutron source and gamma-rays from radioisotope sources were used in the range from 0.081 to 4.438 MeV. Through the precise modeling of the detector structure, the agreement between both results has been improved. A surprising result is that in the PGNAA method the agreement between the MCNP simulation and experiment will be better by using a suitable neutron shield for NaI detector in order to prevent the activation of NaI (Tl) and a proper gamma-shield to attenuate the high-rate 4.438 MeV gamma-ray, (241)Am-Be gamma-ray component.     

Factors Influencing Gel-strengthening at the Mucoadhesive-mucus Interface

Abstract— Mechanical spectroscopy was used to examine some of the factors that may affect mucus gel strengthening: the effect of adding various concentrations of sodium chloride; mucoadhesive polymer molecular weight and its concentration; and the introduction of anionic, cationic and neutral polymers. A reduction in the storage modulus of the mucus/mucoadhesive mixture was observed with the introduction of sodium chloride. A poly(acrylic acid) with a molecular weight of 750 kDa gave the optimum mucus gel strengthening effect relative to other molecular weights. An anionic polymer was found to strengthen the mucus gel much more than a neutral or cationic polymer. It was proposed that the gel strengthening effect could be due to the formation of hydrogen bonded intermolecular complexes between the mucoadhesive and the mucus molecules. Furthermore, the complex formed is influenced by the ionic strength of the environment, and the molecular weight, nature and concentration of the mucoadhesive. In all cases the changes in the rheological properties of the mixes could be correlated directly to the strength of mucoadhesion reported in previous studies.     

Obesity and risk of colorectal cancer: a meta-analysis of 31 studies with 70,000 events.

BACKGROUND: Colorectal cancer is the second most common cause of death and illness in developed countries. Previous reviews have suggested that obesity may be associated with 30% to 60% greater risk of colorectal cancer, but little consideration was given to the possible effect of publication bias on the reported association. METHODS: Relevant studies were identified through EMBASE and MEDLINE. Studies were included if they had published quantitative estimates of the association between general obesity [defined here as body mass index (BMI) > or = 30 kg/m(2)] and central obesity (measured using waist circumference) and colorectal cancer. Random-effects meta-analyses were done, involving 70,000 cases of incident colorectal cancer from 31 studies, of which 23 were cohort studies and 8 were case-control studies. RESULTS: After pooling and correcting for publication bias, the estimated relative risk of colorectal cancer was 1.19 [95% confidence interval (95% CI), 1.11-1.29], comparing obese (BMI > or = 30 kg/m(2)) with normal weight (BMI <25 kg/m(2)) people; and 1.45 (95% CI, 1.31-1.61), comparing those with the highest, to the lowest, level of central obesity. After correcting for publication bias, the risk of colorectal cancer was 1.41 (95% CI, 1.30-1.54) in men compared with 1.08 (95% CI, 0.98-1.18) for women (P(heterogeneity) <0.001). There was evidence of a dose-response relationship between BMI and colorectal cancer: for a 2 kg/m(2) increase in BMI, the risk of colorectal cancer increased by 7% (4-10%). For a 2-cm increase in waist circumference, the risk increased by 4% (2-5%). CONCLUSIONS: Obesity has a direct and independent relationship with colorectal cancer, although the strength of the association with general obesity is smaller than previously reported.