Neutron spectroscopy with TENIS using an artificial neural network.

In this research, a ThErmal Neutron Imaging System (TENIS) consisting of two perpendicular sets of plastic scintillator arrays for boron neutron capture therapy (BNCT) application has been investigated in a completely different approach for neutron energy spectrum unfolding. TENIS provides a thermal neutron map based on the detection of 2.22 MeV gamma-rays resulting from 1H(nth, γ)2D reactions, but in the present study, the 70-pixel thermal neutron images have been used as input data for unfolding the energy spectrum of incident neutrons. Having generated the thermal neutron images for 109 incident mono-energetic neutrons, a 70 × 109 response matrix has been generated using the MCNPX2.6 code for feeding into the artificial neural network tools of MATLAB. The errors of the final results for mono-energetic neutron sources are less than 10% and the root mean square error (RMSE) for the unfolded neutron spectrum of 252Cf is about 0.01. The agreement of the unfolding results for mono-energetic and 252Cf neutron sources confirms the performance of the TENIS system as a neutron spectrometer.

Validity Assessment of an Automated Brain Morphometry Tool for Patients with De Novo Memory Symptoms.

BACKGROUND AND PURPOSE: Automated volumetric analysis of structural MR imaging allows quantitative assessment of brain atrophy in neurodegenerative disorders. We compared the brain segmentation performance of the AI-Rad Companion brain MR imaging software against an in-house FreeSurfer 7.1.1/Individual Longitudinal Participant pipeline. MATERIALS AND METHODS: T1-weighted images of 45 participants with de novo memory symptoms were selected from the OASIS-4 database and analyzed through the AI-Rad Companion brain MR imaging tool and the FreeSurfer 7.1.1/Individual Longitudinal Participant pipeline. Correlation, agreement, and consistency between the 2 tools were compared among the absolute, normalized, and standardized volumes. Final reports generated by each tool were used to compare the rates of detection of abnormality and the compatibility of radiologic impressions made using each tool, compared with the clinical diagnoses. RESULTS: We observed strong correlation, moderate consistency, and poor agreement between absolute volumes of the main cortical lobes and subcortical structures measured by the AI-Rad Companion brain MR imaging tool compared with FreeSurfer. The strength of the correlations increased after normalizing the measurements to the total intracranial volume. Standardized measurements differed significantly between the 2 tools, likely owing to differences in the normative data sets used to calibrate each tool. When considering the FreeSurfer 7.1.1/Individual Longitudinal Participant pipeline as a reference standard, the AI-Rad Companion brain MR imaging tool had a specificity of 90.6%-100% and a sensitivity of 64.3%-100% in detecting volumetric abnormalities. There was no difference between the rate of compatibility of radiologic and clinical impressions when using the 2 tools. CONCLUSIONS: The AI-Rad Companion brain MR imaging tool reliably detects atrophy in cortical and subcortical regions implicated in the differential diagnosis of dementia.

Nurses' experience of caring for people living with HIV: a focused ethnography.

BACKGROUND: Healthcare providers have been found to have limited knowledge and skills in interacting with people living with HIV. These factors can adversely affect providers' practice, jeopardize their safety and compromise the care of the patients. AIMS: This study aimed to explore the experiences of Iranian nurses who were caring for patients with HIV. METHODS: A focused ethnography approach was used. Participants consisted of 12 nurses working in teaching hospitals affiliated to Urmia University of Medical Sciences and recruited by purposeful sampling. Semi-structured interviews, field observations and field notes were used for data collection. Data were analysed employing content analysis. FINDINGS: Three main themes emerged from the analysis of the participants' experiences of providing care to patients with HIV: 'excessive fear of being infected', 'concerns about the possible consequences' and 'lack of self-confidence in care provision'. DISCUSSION/CONCLUSION: Nurses have experienced a great deal of fear of self and cross-contamination when providing care to people living with HIV. Social stigma and discrimination against people living with HIV amplified the nurses' experience of fear. Providing appropriate education and training for nurses can improve their attitudes, emotions and self-confidence while providing care to such people and increasing the quality of care provided. IMPLICATIONS FOR NURSING AND HEALTH POLICY: Planning more educational programmes focusing on improving their misunderstandings about HIV could result in positive outcomes: for nurses to provide high-quality care and for people living with HIV who receive this care. The healthcare system should consider the culture of care provided by nurses to these people.

Shedding light on thyroid hormone disorders and Parkinson disease pathology: mechanisms and risk factors.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons. Dopaminergic system is interconnected with the hypothalamic-pituitary-thyroid axis. Dopamine (DA) upregulates thyrotropin releasing hormone (TRH) while downregulating thyroid stimulating hormone (TSH) and thyroid hormones. Moreover, TRH stimulates DA release. PD is associated with impaired regulation of TSH and thyroid hormones (TH) levels, which in turn associate with severity and different subtypes of PD, while levodopa and bromocriptine treatment can interfere with hypothalamic-pituitary-thyroid axis. Thyroid disturbances, including hypothyroidism, Hashimoto's thyroiditis (HT), hyperthyroidism and Graves' disease (GD) not only increase the risk of PD but also share some clinical signs with PD. Also, several genes including RASD2, WSB1, MAPT, GIRK2, LRRK2 and gene products like neurotensin and NOX/DUOX affect the risk for both PD and thyroid disease. Hypothyroidism is associated with obesity, hypercholesterolemia, anemia and altered cerebral blood flow which are associated with PD pathology. Herein we provide a comprehensive view on the association between PD and thyroid hormones regulation and dysregulations, hoping to provide new avenues towards targeted treatment of PD. We performed a comprehensive search in literature using Pubmed and Scopus, yielding to a total number of 36 original articles that had addressed the association between thyroid hormone disorders and PD.

Bacteriophages as antibiotic resistance genes carriers in agro-food systems.

Antibiotic resistance genes (ARGs) are a global health concern. Antibiotic resistance occurs naturally, but misuse of antibiotics in humans and animals is accelerating the process of antibiotic resistance emergency, which has been aggravated by exposure to molecules of antibiotics present in clinical and agricultural settings and the engagement of many countries in water reuse especially in Middle East and North Africa region. Bacteriophages have the potential to be significant actors in ARGs transmission through the transduction process. These viruses have been detected along with ARGs in non impacted habitats and in anthropogenic impacted environments like wastewater, reclaimed water and manure amended soil as well as minimally processed food and ready to eat vegetables. The ubiquity of bacteriophages and their persistence in the environment raises concern about their involvement in ARGs transmission among different biomes and the generation of pathogenic-resistant bacteria that pose a great threat to human health. The aim of this review is to give an overview of the potential role of bacteriophages in the dissemination and the transfer of ARGs to pathogens in food production and processing and the consequent contribution to antibiotic resistance transmission through faecal oral route carrying ARGs to our dishes.

Indentation and Transverse Diameter of the Meckel Cave: Imaging Markers to Diagnose Idiopathic Intracranial Hypertension.

BACKGROUND AND PURPOSE: Clinical and imaging manifestations of idiopathic intracranial hypertension should prompt early diagnosis and treatment to avoid complications. Multiple diagnostic imaging criteria are reported to suggest the diagnosis of idiopathic intracranial hypertension with questionable sensitivity and/or specificity. Increased intracranial pressure results in dilation of the perineural cisternal spaces such as the optic nerve sheaths and the Meckel cave. It may also cause protrusion of cisternal structures of the Meckel cave through the skull base foramina, which could result in indentation or a bilobed appearance of the Meckel cave. We investigated the changes in the Meckel cave in patients with proved idiopathic intracranial hypertension versus healthy controls. MATERIALS AND METHODS: We studied 75 patients with a diagnosis of idiopathic intracranial hypertension and 75 age-and sex-matched healthy controls. The transverse diameter of Meckel cave was measured in the axial and coronal planes of T2-weighted MR imaging sequences, and comparison was made between the 2 groups. RESULTS: The mean diameters of the Meckel cave on the coronal T2 plane in patients with idiopathic intracranial hypertension were 5.21 ± 1.22 mm on the right side and 5.16 ± 0.90 mm on the left side, while in the control group, they measured 3.89 ± 0.62 mm and 4.09 ± 0.68 mm, respectively (P value < .001). Of 75 patients with an approved diagnosis of idiopathic intracranial hypertension, 57 (76%) showed an indented Meckel cave as opposed to 21 (28%) in the control group. CONCLUSIONS: Our results confirm for the first time that the shape and size of the Meckel cave can be used as sensitive and specific diagnostic imaging markers for the diagnosis of idiopathic intracranial hypertension.

Correction: Ultrasound-assisted leaching of vanadium from fly ash using lemon juice organic acids.

[This corrects the article DOI: 10.1039/C9RA09325G.].

Conceptual design for a new heterogeneous 241Am-9Be neutron source assembly using SOURCES4C-MCNPX hybrid simulations.

In this study, an approach to simulate a novel variable-yield heterogeneous 241Am-9Be was proposed with a hybrid use of SOURCES4C and MCNPX codes, and its energy spectrum and neutron emission yield were simulated. In these simulations, the energy spectra of the alpha particles emitted from the americium source and the neutrons produced within the beryllium and oxygen contents as a result of 9Be(α,n) and 17,18O(α,n) reactions were calculated with SOURCES4C whilst the neutron transport from neutron production points to the space outside the source assembly were performed with the MCNPX code. The neutron energy spectrum and neutron emission yield for two different configurations of single-rod and multi-rod sources (i.e., americium or americium oxide rods in beryllium medium) were compared to a source of homogeneous americium (or its oxides) and beryllium mixture. The proposed heterogeneous geometry was aimed to provide a neutron source with a variable neutron yield, easy-to-shut down and easy-to-waste process features. The results confirmed that the homogeneous source represented the largest neutron yield compared to single- and multi-rod geometries. However, the neutron yield in heterogenous geometry could be altered by varying the number of americium (or americium oxide) rods to reach the desired neutron yield.

Gene expression and levels of IL-6 and TNFα in PBMCs correlate with severity and functional class in patients with chronic heart failure.

BACKGROUND: Evidence shows that proinflammatory cytokines are important determinants of assessment of severity and prognosis of chronic heart failure (CHF). AIMS: We investigated whether peripheral expression of the proinflammmatory factors, TNF-α and IL-6 can predict variable of clinical assessment of patients with CHF. METHODS: In this report, we used real-time PCR assay to compare relative gene expression of TNFα and IL-6 in PBMC from CHF patients with various heart diseases (n = 42, EF < 45%, NYHA I to IV) and matched healthy control subjects (n = 42).We also determined the TNFα and IL-6 concentrations of cell culture supernatant of PBMCs with ELISA. RESULTS: There was a significant negative correlation between gene expression of TNFα and LVEF(r = 0.4, p < 0.05). Patients with CHF had increased gene expression of TNFα and IL-6 in PBMCs (p < 0.05). They also had elevated the supernatant levels of these cytokines in cultured PBMCs (p < 0.001). Levels of TNFα and IL-6 were increased in ischemic heart disease compared to non-ischemic heart disease. There was a positive correlation between TNFα and IL-6 levels in CHF patients and severity of CHF in patients. Levels of these cytokines were higher in patients with NYHA III-IV than in NYHA I-II and normal subjects. CONCLUSIONS: Results of this study indicate that peripheral expression of proinflammatory cytokines, TNF-α and IL-6, is important indicators of severity and prognosis in patients with chronic heart disease.

Single nucleotide polymorphisms of IL-2, but not IL-12 and IFN-y, are associated with increased susceptibility to chronic spontaneous urticaria

Background: A clear picture of interaction of Th1/Th2 cytokines in pathogenesis of chronic spontaneous urticaria (CSU), remains elusive. Impaired IFN-γ production and decreased levels of IL-2 have been reported. The aim of this study was to evaluate the association of Th1 cytokines; IL-2, IL-12 and IFN-γ polymorphisms with CSU. Methods: 90 patients with CSU and 140 age-sex matched subjects were included in this study. DNA samples were evaluated through PCR-SSP assay in order to detect single nucleotide polymorphisms of IL-12 (A/C -1188) or (rs3212227), IFN-γ (A/T UTR5644) or (rs2069717) and IL-2 (G/T -330 and G/T +166) or (rs2069762 and rs2069763). Results: G allele at -330 at promoter region of IL-2 gene was overrepresented in CSU. Heterozygotes (GT) at this locus and heterozygotes at +166 of IL-2 gene (GT) were more prevalent in CSU group. Additionally, the haplotype GT for loci -330 and +166 of IL-2 gene was powerfully associated with CSU (OR (95%CI) = 57.29 (8.43-112.7)). Conclusions: SNP at position -330 and +166 of IL-2 gene are differently expressed in CSU. The haplotype GT of IL-2 at -330 and +166 might confer vulnerability to a number of immunological disorders in Iranian region (AU)

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Single nucleotide polymorphisms of IL-2, but not IL-12 and IFN-γ, are associated with increased susceptibility to chronic spontaneous urticaria.

BACKGROUND: A clear picture of interaction of Th1/Th2 cytokines in pathogenesis of chronic spontaneous urticaria (CSU), remains elusive. Impaired IFN-γ production and decreased levels of IL-2 have been reported. The aim of this study was to evaluate the association of Th1 cytokines; IL-2, IL-12 and IFN-γ polymorphisms with CSU. METHODS: 90 patients with CSU and 140 age-sex matched subjects were included in this study. DNA samples were evaluated through PCR-SSP assay in order to detect single nucleotide polymorphisms of IL-12 (A/C -1188) or (rs3212227), IFN-γ (A/T UTR5644) or (rs2069717) and IL-2 (G/T -330 and G/T +166) or (rs2069762 and rs2069763). RESULTS: G allele at -330 at promoter region of IL-2 gene was overrepresented in CSU. Heterozygotes (GT) at this locus and heterozygotes at +166 of IL-2 gene (GT) were more prevalent in CSU group. Additionally, the haplotype GT for loci -330 and +166 of IL-2 gene was powerfully associated with CSU (OR (95%CI)=57.29 (8.43-112.7)). CONCLUSIONS: SNP at position -330 and +166 of IL-2 gene are differently expressed in CSU. The haplotype GT of IL-2 at -330 and +166 might confer vulnerability to a number of immunological disorders in Iranian region.

Investigation on the reflector/moderator geometry and its effect on the neutron beam design in BNCT.

In order to provide an appropriate neutron beam for Boron Neutron Capture Therapy (BNCT), a special Beam Shaping Assembly (BSA) must be designed based on the neutron source specifications. A typical BSA includes moderator, reflector, collimator, thermal neutron filter, and gamma filter. In common BSA, the reflector is considered as a layer which covers the sides of the moderator materials. In this paper, new reflector/moderator geometries including multi-layer and hexagonal lattice have been suggested and the effect of them has been investigated by MCNP4C Monte Carlo code. It was found that the proposed configurations have a significant effect to improve the thermal to epithermal neutron flux ratio which is an important neutron beam parameter.

Feasibility study of using laser-generated neutron beam for BNCT.

The feasibility of using a laser-accelerated proton beam to produce a neutron source, via (p,n) reaction, for Boron Neutron Capture Therapy (BNCT) applications has been studied by MCNPX Monte Carlo code. After optimization of the target material and its thickness, a Beam Shaping Assembly (BSA) has been designed and optimized to provide appropriate neutron beam according to the recommended criteria by International Atomic Energy Agency. It was found that the considered laser-accelerated proton beam can provide epithermal neutron flux of ∼2×10(6) n/cm(2) shot. To achieve an appropriate epithermal neutron flux for BNCT treatment, the laser must operate at repetition rates of 1 kHz, which is rather ambitious at this moment. But it can be used in some BNCT researches field such as biological research.

Optimization of the beam shaping assembly in the D-D neutron generators-based BNCT using the response matrix method.

Optimization of the Beam Shaping Assembly (BSA) has been performed using the MCNP4C Monte Carlo code to shape the 2.45 MeV neutrons that are produced in the D-D neutron generator. Optimal design of the BSA has been chosen by considering in-air figures of merit (FOM) which consists of 70 cm Fluental as a moderator, 30 cm Pb as a reflector, 2mm (6)Li as a thermal neutron filter and 2mm Pb as a gamma filter. The neutron beam can be evaluated by in-phantom parameters, from which therapeutic gain can be derived. Direct evaluation of both set of FOMs (in-air and in-phantom) is very time consuming. In this paper a Response Matrix (RM) method has been suggested to reduce the computing time. This method is based on considering the neutron spectrum at the beam exit and calculating contribution of various dose components in phantom to calculate the Response Matrix. Results show good agreement between direct calculation and the RM method.

Ulexite-galena intermediate-weight concrete as a novel design for overcoming space and weight limitations in the construction of efficient shields against neutrons and photons.

Recently, due to space and weight limitations, scientists have tried to design and produce concrete shields with increased attenuation of radiation but not increased mass density. Over the past years, the authors' had focused on the production of heavy concrete for radiation shielding, but this is the first experience of producing intermediate-weight concrete. In this study, ulexite (hydrated sodium calcium borate hydroxide) and galena (lead ore) have been used for the production of a special intermediate-weight concrete. Shielding properties of this intermediate-weight concrete against photons have been investigated by exposing the samples to narrow and broad beams of gamma rays emitted from a 6°Co radiotherapy unit. Densities of the intermediate-weight concrete samples ranged 3.64-3.90 g cm⁻³, based on the proportion of the ulexite in the mix design. The narrow-beam half-value layer (HVL) of the ulexite-galena concrete samples for 1.25 MeV 6°Co gamma rays was 2.84 cm, much less than that of ordinary concrete (6.0 cm). The Monte Carlo (MC) code MCNP4C was also used to model the attenuation of 6°Co gamma-ray photons and Am-Be neutrons of the ulexite-galena concrete with different thicknesses. The 6°Co HVL calculated by MCNP simulation was 2.87 cm, indicating a good agreement between experimental measurements and MC simulation. Furthermore, MC-calculated results showed that thick ulexite-galena concrete shields (60-cm thickness) had a 7.22 times (722 %) greater neutron attenuation compared with ordinary concrete. The intermediate-weight ulexite-galena concrete manufactured in this study may have many important applications in the construction of radiation shields with weight limitations such as the swing or sliding doors that are currently used for radiotherapy treatment rooms.

Silymarin regulates the cytochrome P450 3A2 and glutathione peroxides in the liver of streptozotocin-induced diabetic rats.

This study aimed to investigate the protective and regulatory effects of silymarin (SMN) and melatonin (MEL) on streptozotocin (STZ)-induced diabetic changes in cytochrome P450 3A2 (CYP 3A2) and glutathione peroxidase (GPX) expression and antioxidant status in the liver. Male Wistar rats were divided into five groups, including: control (C), untreated diabetic animals (D), SMN-treated diabetics (S, 50 mg/kg, orally), MEL-treated diabetics (M, 10 mg/kg, i.p.), and SMN plus MEL-treated diabetics (S+M). Diabetes was induced by a single intraperitoneal injection of STZ (50 mg/kg). The blood glucose level, daily urinary volume and body weight changes were measured. After the 28 days treatment period, antioxidant status was analyzed by means of the determination of malondialdehyde (MDA) content, nitric oxide (NO) and total thiol molecules (TTM) levels in the liver. The glycogen depletion in the liver was examined by histochemical staining. The CYP 3A2 and GPX expression at mRNA level was determined using RT-PCT technique. SMN and MEL both individually or in combination prevented from diabetes-induced weight loss and lowered daily urinary volume significantly (p<0.05). None of the test compounds could lower the blood glucose level significantly (p>0.05). Both SMN and MEL could convert the diabetes induced elevated levels of MDA and NO and the diabetes-reduced TTM content to the control level. Moreover, the diabetes-up regulated CYP 3A2 and down regulated GPX, returned to normal values after SMN treatment. Histochemical and histopathological examinations revealed that the diabetes-induced glycogen-depletion and single cell necrosis markedly improved with the SMN and SMN plus MEL treatment. Our data suggest that the STZ-induced diabetes in addition of disturbing the antioxidant status, alters the expression levels of CYP 3A2 and GPX. Moreover, the SMN and SMN plus MEL treatment was able to normalize both the antioxidant status and the expression of CYP 3A2 and GPX in the liver of diabetic rats.

Long-term administration of Silymarin augments proinflammatory mediators in the hippocampus of rats: evidence for antioxidant and pro-oxidant effects.

Silymarin (SMN) is used as an antioxidant complex to attenuate the pro-oxidant effects of toxic agents. This study was designed to investigate the impact of a long-term administration of SMN on proinflammatory mediators, oxidative stress biomarkers and on the levels of interleukin-1ß (IL-1ß) transcript in the hippocampus. A total of 40 adult male Wistar rats were assigned into control and test groups. Animals in the test group were subdivided into four subgroups according to the following treatment profile: carbon tetrachloride (CCl(4), 0.5 ml/kg), SMN 25, SMN 50 and SMN 100 (mg/kg). The animals received the compounds by gastric gavage. Following the 8-week treatment period, animals in the CCl(4) group showed body weight loss, while the test groups except SMN 100 revealed a significant (p < 0.05) positive body weight gain. The levels of nitric oxide (NO) and malondialdehyde (MDA) as pro-oxidant and lipid peroxidation index, respectively, increased in CCl(4)- and SMN 100-treated groups, while SMN at lower dose levels did not alter the NO and MDA content. The concentration of total thiol molecules increased in the SMN 50 group and showed a remarkable decrease in CCl(4) and SMN 100 groups. Animals treated with CCl(4) or SMN 100 showed an upregulation of IL-1ß, while animals in SMN 25 and SMN 50 groups showed a slight downregulation of expression of IL-1ß at the messenger RNA level. These findings suggest that SMN at higher dosage level might exert pro-oxidant effect as an increase in the level of MDA and proinflammatory mediators such as NO, and upregulation of IL-1ß in the hippocampus were shown.

Effect of HFE variants on sphingolipid expression by SH-SY5Y human neuroblastoma cells.

C282Y and H63D are two common variants of the hemochromatosis protein HFE. SH-SY5Y human neuroblastoma cells stably transfected to express either wild type HFE (WT-HFE), or the C282Y or H63D allele were analyzed for effect of expression of the mutant proteins on transcription of 14 enzymes involved in sphingolipid metabolism. Cells expressing the C282Y variant showed significant increases (>2-fold) in transcription of five genes and decreases in two compared to that seen for cells expressing WT-HFE, while cells expressing the H63D variant showed an elevation in transcription of one gene and a decrease in two. These changes were seen as alterations in ganglioside composition, cell surface binding by the binding subunit of cholera toxin, expression of sphingosine-kinase-1 and synthesis of sphingosine-1-phosphate. These changes may explain why C282Y-HFE is a risk factor for colon and breast cancer and possibly protective against Alzheimer's disease while H63D-HFE is a risk factor for neurodegenerative diseases.

A water-soluble fragment of Micrococcus lysodeikticus cell wall.

A fragment of Micrococcus lysodeikticus cell wall was obtained by extraction of walls with water, dimethylformamide or dimethyl sulfoxide. The water-soluble polymer was obtained from the cell walls prepared either with or without trypsin treatment of the cell. This fragment was studied by the Smith periodate oxidation, methylation, mild acid treatment and enzymic procedures. The polymer consists of polysaccharide chains composed of (1-->4)-O-(2-acetamido-2-deoxy-beta-D-mannopyranosyluronic acid)-(1-->6)-O-alpha-D-glucopyranosyl residues. The polysaccharide chain is linked to C-6 of a 2-acetamido-3-O-(D-1-carboxyethyl)-2-deoxy-beta-D-gluco-pyranosyl residue of a peptidoglycan chain composed of repeating (1-->4)-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-(1-->4)-[2-acet ami do-3-O-(D-1-carboxyethyl)-2-deoxy-beta-D-glucopyranosyl] residues. The water-soluble cell-wall fragment was also observed in the-culture medium of Micrococcus lysodeikticus and was also extractable from the cells in minor quantity.