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Neural correlates of cognitive intervention in persons at risk of developing Alzheimer's disease.
Cognitive training is an emergent approach that has begun to receive increased attention in recent years as a non-pharmacological, cost-effective intervention for Alzheimer's disease (AD). There has been increasing behavioral evidence regarding training-related improvement in cognitive performance in early stages of AD. Although these studies provide important insight about the efficacy of cognitive training, neuroimaging studies are crucial to pinpoint changes in brain structure and function associated with training and to examine their overlap with pathology in AD. In this study, we reviewed the existing neuroimaging studies on cognitive training in persons at risk of developing AD to provide an overview of the overlap between neural networks rehabilitated by the current training methods and those affected in AD. The data suggest a consistent training-related increase in brain activity in medial temporal, prefrontal, and posterior default mode networks, as well as increase in gray matter structure in frontoparietal and entorhinal regions. This pattern differs from the observed pattern in healthy older adults that shows a combination of increased and decreased activity in response to training. Detailed investigation of the data suggests that training in persons at risk of developing AD mainly improves compensatory mechanisms and partly restores the affected functions. While current neuroimaging studies are quite helpful in identifying the mechanisms underlying cognitive training, the data calls for future multi-modal neuroimaging studies with focus on multi-domain cognitive training, network level connectivity, and individual differences in response to training
Educational Ethics in Academic Environment: Medical Students' Perspectives
Background and Objective: Educational ethics imply values such as honesty, reliance on one's own personal
effort, not to abuse the efforts of others, and respect the dignity and respect for others. Students are faced
with different situations in which they show various moral and immoral behaviors. This study aimed to
explore medical students' viewpoints and experiences at Golestan University of Medical Sciences about
ethics in academic environment in 2013.
Materials and Methods: In this qualitative study a purposive sampling was used with maximum variation
and 12 medical students participated in the research. Data was gathered using semi-structured interviews. At
least an open question "When I say ethics in education or educational environment, what comes to your
mind" was repeated in all the interviews. The interviews recorded and transcribed line by line and then
analyzed according to "conventional content analysis" method.
Results: "Respecting teacher dignity", "preserving dignity of classroom", "respecting and maintaining
dignity for classmates", "seeking for knowledge and sciences” emerged as the main themes of the current
study.
Conclusion: University students considered learning environment as a sacred place; conforming its expected
rules and ethics would be mandatory. Abnormal behavior causes not only loss of students dignity but also
could be harmful to the calmness of educational atmosphere and may evoke different unpleasant pessimistic
ideas about such academic environment
Identification of appropriate tools of information and communication technologies (ICT) in the improvement of food security of Iran's rural households
Access to sufficient and desirable food is one of the principles of any developing and healthy society. One of the important means for attainment of food security is information and communication technologies (ICT). The purpose of the research was to identify appropriate tools of ICT in improving food security of Iran's rural households. The population for this research was 253 extension experts from eight provinces, out of this population, 170 were selected as sample by proportion stratified sampling between 2006 and 2007. This is an applied research with descriptive-survey methodology. The main tool for collecting data was questionnaire. After data extraction, statistical analysis was carried out using SPSS version 13. The results showed that from the view point of the experts, the situation of food security was unfavorable (81.2%). However, ICT can improve food security of rural households. From the viewpoint of experts, rural households have more accessibility to radio, television, phone, face to face interaction and audio cassettes. Radio, television, audio cassettes, workshop and scientific trips are more cost effective than other tools. In addition to television, workshop, scientific trips, exhibition and printed materials are more relevant to rural households needs. Rural households also have more access to old technologies; these technologies are more cost effective and more relevant to the households needs.Key words: Information andcommunication technologies (ICT), tools, food security, rural households, agricultural extension experts
Effect of citric acid and microbial phytase on serum enzyme activities and plasma minerals retention in broiler chicks
An experiment was conducted to study the effect of microbial phytase supplementation and citric acid in broiler chicks fed corn-soybean meal base diets on enzyme activities and some blood parameters of serum and plasma minerals concentration in Ross 308 strain broilers. The data was analysed using a randomized complete block design with factorial arrangement of 3×3, three levels of citric acids (0, 3 and 6%) and three levels of phytase (0, 500 and 1000 enzyme unit per kg). There were three replicates for each treatment that total to 270 chicks for the whole experiment. The results indicated that addition of citric acid to diets caused significant decrease in alkaline phosphatase (P<0.05), lactate dehydrogenase (P<0.01) activities, cholesterol (P<0.05) and plasma phosphorus (P) (P<0.01) and Fe (P<0.05) concentrations. Microbial phytase caused significant decrease (P<0.01) in serum enzyme activities and plasma Fe concentration and significantly increased (P<0.01) aspartate aminotransferase activity, triglyceride and plasma P concentration. Microbial phytase and citric acid could modify some serum enzyme activities and increase the availability and use of minerals for growth and performance improvement of broilers. It is therefore necessary to re-evaluate mineral requirements of broiler chickens when a diet is supplemented with phytase and citric acid.Key words: Citric acid, microbial phytase, plasma minerals, serum enzyme activity, broilers
The perception of Agricultural Researchers about the Role of Nanotechnology in Achieving Food Security
Agricultural researchers in the Province of Isfahan were surveyed in order to explore their perception about role of nanotechnology in food security. The methodology used in this study involved a combination of descriptive and quantitative research and included the use of correlation, regression and descriptive analysis as data processing methods. The total population for this study was 76 agriculture researchers in the Isfahan Province. Data were collected through interview schedules. Based on the results of the mean score, researchers did not agree that nanotechnology could help in achieving food security, although they believed this technology could have more impact on affordability and safety of food products than other dimension of food security. As regression analysis showed, necessary conditions for application of nanotechnology, producing agricultural products, consuming nanotechnology products and constraints in application of nanotechnology caused 21% of variance on the perception of researchers regarding the role of nanotechnology in achieving food security. Based on the perception of respondents, the main constraint in application of nanotechnology in agricultural sector was regulatory constraints.Key words: Agricultural researchers, nanotechnology, Isfahan Province, food security
Investigating the Neurotoxicity Caused by Tricyclazole and Thiophanate Methyl in Wistar Rats
Background and Objective: Along with the steady growth of the population, the widespread use of systemic fungicides, which leads to increased productivity and higher yield of food products, has been given a lot of attention. Therefore, considering the cytotoxic effects of systemic fungicides tricyclazole and thiophanate methyl, the present study was conducted with the aim of investigating the neurotoxicity caused by the use of fungicides tricyclazole (TCZ) and thiophanate methyl (TM) in Wistar rats.
Methods: In this experimental study, 32 male Wistar rats were randomly divided into 4 groups of 8 including: control group, groups receiving pesticide mixtures orally at doses of (A) TM 664 + TCZ 25, (B) TM 498 + TCZ 19 and (C) TM 332 + TCZ 13 (mg/kg body weight) and brain tissue sampling was done after 28 days. Nissl and hematoxylin-eosin staining were used for qualitative assessment of pathological lesions and quantitative counting of brain cells.
Findings: In the histopathological examinations of the groups that received toxins, it was observed that the neurons became necrotic, and the increase of microglia cells in the hippocampus and cerebral cortex was also observed. The results of cell counting indicated the lowest number of neurons in group A in the cerebral cortex (171.40±4.88), CA1 (152.80±5.99), CA2,3 (127.90±8.36) and CA4 (59.20±3.86), which showed a significant decrease compared to the control group (p<0.05).
Conclusion: The results of the study showed that the mixture of tricyclazole and thiophanate methyl caused damage to brain neurons in the cerebral cortex and different areas of the hippocampus and subsequently caused a decrease in the number of neurons in these areas; Of course, the amount of damage was directly related to increase in the dose
Oral poliovirus vaccine-induced programmed cell death involves both intrinsic and extrinsic pathways in human colorectal cancer cells.
PURPOSE: Colorectal cancer (CRC) is one of the most common causes of cancer death throughout the world. Replication-competent viruses, which are naturally able to infect and lyse tumor cells, seem to be promising in this field. The aim of this study was to evaluate the potential of oral poliovirus vaccine (OPV) on human CRC cells and elucidate the mechanism of apoptosis induction. MATERIALS AND METHODS: Protein and gene expression of poliovirus (PV) receptor (CD155) on four human CRC cell lines including HCT116, SW480, HT-29, and Caco-2 and normal fetal human colon (FHC) cell line as a control were examined by flow cytometry and SYBR Green Real-Time PCR, respectively. Cytotoxicity of OPV on indicated cell lines was tested using MTT assay. The ability of OPV on apoptosis induction for both intrinsic and extrinsic pathways was examined using caspase-8 and caspase-9 colorimetric assay kits. The PV propagation in mentioned cell lines was investigated, and the quantity of viral yields (cells associated and extracellular) was determined using TaqMan PCR. RESULTS: CD155 mRNA and protein were expressed significantly higher in studied CRC cell lines rather than the normal cell line (P=0). OPV induced cell death in a time- and dose-dependent manner in human CRC cells. Apoptosis through both extrinsic and intrinsic pathways was detected in CRC cells with the minimum level found in FHC. PV viral load was significantly correlated with apoptosis via extrinsic (R=0.945, P=0.0001) and intrinsic (R=0.756, P=0.001) pathways. CONCLUSION: This study suggests that OPV has potential for clinical treatment of CRC. However further studies in animal models (tumor xenografts) are needed to be certain that it is qualified enough for treatment of CRC
Molecular detection of blaVEB-1 beta-lactamase encoding gene among extended spectrum B-Lactamase positive wound isolates of Pseudomonas aeruginosa
Background: Pseudomonas aeruginosa is considered as a leading cause of nosocomial infections. Burn and wound infections are mainly caused by multidrug-resistant P. aeruginosa isolates. Drug resistance frequently occurs among nosocomial isolates and can usually resist a myriad of antibiotics such as novel β-lactam antibiotics. Detection of multidrug-resistant isolates could assist better drug administration. Objectives: The aim of this study was to detect Extended Spectrum Beta-Lactamases (ESBL) positive wound isolates and the genes encoding blaVEB-1 ESBL among wound isolates of P. aeruginosa. Materials and Methods: A total of 89 wound isolates of P. aeruginosa were collected from patients (47 (n = 42) were male and 53 (n = 47) were female) at six Iranian hospitals between years 2009 and 2011. Antibiotic susceptibility and phenotypic ESBL production tests were conducted. The combined disk was used to determine ESBLs production. The blaVEB-1 gene was detected with the polymerase chain reaction (PCR). Results: The majority of the wound isolates were resistant to augmentin (90, n = 80) and cefpodoxime (87.6, n = 78). However, the majority was susceptible to imipenem and meropenem. Fifty-eight (42) wound isolates were ESBL positive. The antibiotic resistance amongst ESBL positive isolates was relatively higher than ESBL negative isolates. Twenty-three (40) ESBL-positive isolates amplified the blaVEB-1 gene. Conclusions: More than behalf of the wound isolates were ESBL positive, and the presence of blaVEB-1 was determined in less than half of these isolates. Fortunately, resistance to imipenem and meropenem was low. © 2015 Pediartric Infections Research Center
DOA estimation using multiple measurement vector model with sparse solutions in linear array scenarios
A novel algorithm is presented based on sparse multiple measurement vector (MMV) model for direction of arrival (DOA) estimation of far-field narrowband sources. The algorithm exploits singular value decomposition denoising to enhance the reconstruction process. The proposed multiple nature of MMV model enables the simultaneous processing of several data snapshots to obtain greater accuracy in the DOA estimation. The DOA problem is addressed in both uniform linear array (ULA) and nonuniform linear array (NLA) scenarios. Superior performance is demonstrated in terms of root mean square error and running time of the proposed method when compared with conventional compressed sensing methods such as simultaneous orthogonal matching pursuit (S-OMP), l_2,1 minimization, and root-MUISC
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