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991.
Z Taslimi R Arezoomandan A Omranifard M Ghalandari-Shamami E Riahi AA Vafaei A Rashidy-Pour A Haghparast 《Peptides》2012,37(2):225-232
It has been shown that orexin A in the ventral tegmental area (VTA) is necessary for development of morphine place preference. Additionally, D1 and D2 dopamine receptors in the nucleus accumbens (NAc) have critical roles in motivation and reward. However, little is known about the function of orexin in conditioned place preference (CPP) in rats and involvement of D1/D2 receptors in the NAc. In the present study, we investigated the effect of direct administration of orexin A into the VTA, and examined the role of intra-accumbal dopamine receptors in development (acquisition) of reward-related behaviors in the rats. Adult male Wistar rats were unilaterally implanted by two separate cannulae into the VTA and NAc. The CPP paradigm was used, and, conditioning score and locomotor activity were recorded by Ethovision software. The results showed that unilateral intra-VTA administration of orexin A (27, 53 and 107ng/0.3μl saline) during conditioning phase induced CPP in a dose-dependent manner. The most effective dose of intra-VTA orexin-A in eliciting CPP was 107ng. However, intra-NAc administration of SCH 23390 (0.25, 1 and 4μg/0.5μl saline), a D1 receptor antagonist, and sulpiride (0.25, 1 and 4μg/0.5μl DMSO), a D2 receptor antagonist, inhibited the development of orexin-induced CPP. The inhibitory effect of D2 but not D1 receptor antagonist was exerted in a dose-dependent manner. It is supposed that the activation of VTA dopaminergic neuron by orexin impresses the D2 receptors more than D1 receptors in the NAc. 相似文献
992.
Falahati M Saboury AA Ma'mani L Shafiee A Rafieepour HA 《International journal of biological macromolecules》2012,50(4):1048-1054
Immobilization of enzymes into the mesoporous nanomaterials results in formation of more stable and even more active versions of biocatalysts. The effect of surface functionalization of mesoporous silica nanoparticles (MSNs) on its adsorption characteristics and stability of superoxide dismutase (SOD) was investigated. For this purpose, non-functionalized (KIT-6) and aminopropyl-functionalized cubic Ia3d mesoporous silica ([n-PrNH(2)-KIT-6]) nanoparticles with 3-dimensional pores were used as supports. It was observed that the amount of enzyme adsorbed on/within MSNs is dependent on the initial enzyme concentration for both KIT-6 and [n-PrNH(2)-KIT-6] mesoporous silicas. However a stronger interaction between SOD and [n-PrNH(2)-KIT-6] was observed relative to KIT-6. Increasing temperature favors a larger amount of SOD immobilization into KIT-6, while it was negligible for [n-PrNH(2)-KIT-6]. Immobilized SOD was more stable against urea and thermal denaturation relative to free enzyme and this improvement of stability was more pronounced for SOD into the [n-PrNH(2)-KIT-6] than KIT-6. These results may be useful in determining the mechanism(s) of protein immobilization and stabilization into the solid supports. 相似文献
993.
Narjes Okati Abbas Esmaili Sari Seyed Mahmood Ghasempouri 《Biological trace element research》2012,149(2):155-162
Coastal populations with high seafood consumption in the South Caspian Sea (Iran) have a significant exposure to dietary mercury. This study assesses the biomonitoring of mercury in mothers and breastfed infants in the South Caspian Sea. The mean of mercury concentration in the hair of 93 pairs of mothers and infants was obtained and was 3.55 and 1.89???g?g?1, respectively. A statistically significant correlation (R?=?0.850, P?=?0.000) was seen between mercury concentration in the hair of mothers and infants. The results of this study indicate that hair mercury concentrations exceeded the USEPA reference dose of 1???g?g?1 in 82.7?% of mothers and 61.2?% of infants. Also, 31?% of the mothers and 10.7?% of the infants had mercury concentrations more than the WHO ??threshold?? level (5???g?g?1). The age and fish consumption of mothers were the factors that significantly affected the hair mercury concentration of mothers and infants. Number of dental amalgam fillings of mothers was the factor that only affected mercury in the hair of mothers. According to the results, we can conclude that the main determinant of mercury exposure was the intake of mercury through fish consumption of mothers. 相似文献
994.
Response of Different Antibiotic Resistant Group of Streptococcus pyogenes to Environmental Stresses
Naser Abbas Mahmoud Ismail Mohamed El-Shahat Ebeid 《Indian journal of microbiology》2012,52(3):354-359
Streptococcus species is considered as an important pathogen for human and animals. The antibiotic resistance mechanism in this species is continuously increased. On the other side, the tolerance of environmental stresses play an effective role in the severity of many streptococcal causative disease. In this study we assayed survey on the causative agents of pharyngitis and tonsillitis patients. The predominant causative strain was Streptococcus pyogenes with 93 % isolating ratio frequency. The other pathogenic species were S. agalactia 5.3 % and S. pneumonia 1.7 %. According to the antibiotic resistant test the S. pyogenes isolates were classified into six different groups. A selected strain from each antibiotic resistant group was tested for tolerance of a restrictive environmental factors. The variations of the environmental niches of isolates were in consistence with their antibiotic resistant variation. 相似文献
995.
Moravej A Rasouli M Kalani M Asaei S Kiany S Najafipour S Koohpayeh A Abdollahi A 《Molecular biology reports》2012,39(6):6907-6914
Lymphotoxin-α (LT-α) and interleukin-1beta (IL-1β) are proinflammatory cytokines playing important roles in immunity against
Leishmania infection and the outcome of the disease. As cytokine productions are under the genetic control, this study tried to find
any probable relationship between these cytokine gene polymorphisms and the susceptibility to visceral leishmaniasis in Iranian
pediatric patients. Ninety-five pediatric patients involved with visceral leishmaniasis and 128 non-relative healthy people,
from the same area as the patients, were genotyped for LT-α (+252A/G) and IL-1β (+3953T/C and −511T/C) gene polymorphisms
using polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP). There was not found any significant differences
in allele and genotype frequencies of LT-α (+252A/G) and IL-1β (+3953) among the study groups. However, the frequency of IL-1β
−511TT genotype was higher in the controls (P = 0.0004) while the frequency of IL-1β −511CC genotype and C allele were higher in the patients (P = 0.008 and P = 0.00006, respectively). Furthermore, IL-1β CC (−511/+3953) haplotype was more frequent in VL patients compared with the
controls (P = 0.0002) and the distribution of TT haplotype was higher in the controls compared with the patients (P = 0.003). In conclusion, based on the results, IL-1β −511C allele, CC genotype and CC (−511/+3953) haplotype could be considered
as the susceptibility factors for visceral leishmaniasis while IL-1β −511TT genotype, T allele and TT haplotype (−511/+3953)
might be counted as the influential factors for resistance to the disease. 相似文献
996.
Sadati N Jenett-Siems K Siems K Ardekani MR Hadjiakhoondi A Akbarzadeh T Ostad SN Khanavi M 《Zeitschrift für Naturforschung. C, Journal of biosciences》2012,67(5-6):275-281
The n-butanolic fraction of a methanolic extract (80%) from aerial parts of Ajuga chamaecistus ssp. tomentella was analysed using different chromatographic methods. Column (CC) and high-performance liquid chromatography (HPLC) were used for isolation and purification. 13C, H NMR, H-H COSY, HSQC, HMBC, and ESI-MS were employed for identification of the compounds isolated from this fraction. The structures of the compounds were determined to be cis-melilotoside (1), trans-melilotoside (2), lavandulifolioside (3), 20-hydroxyecdysone (4), leonoside B (5), martynoside (6), ajugalactone (7), makisterone A (8), and 24-dehydroprecyasterone (9). This is the first report on the presence of cis- and trans-melilotoside in Ajuga species. Cytotoxic evaluation of the n-butanolic fraction, cis- and trans-melilotoside against cancer (T47D, HT-29, and Caco-2) and normal (NIH 3T3) cell lines by the mitochondrial tetrazolium test (MTT) showed no cytotoxic effects up to 400 microg/mL. The results of this study suggest that melilotoside, phenylethyl glycosides, and phytoecdysteroids are the main constituents of the n-butanolic fraction of Ajuga chamaecistus ssp. tomentella. 相似文献
997.
Khansa S Hoteit R Shammaa D Khalek RA El Halas H Greige L Abbas F Mahfouz RA 《Gene》2012,506(2):396-399
Aims
Being one of the most polymorphic genetic systems , the Human Leukocyte Antigen system is divided into class I (HLA-A, HLA-B and HLA-C) and class II (HLA-DP, -DQ and -DR). This study is the first and largest of its kind to describe the distribution of HLA-DQB1 and HLA-DRB1 alleles in Lebanon and the region.Methods
Respectively, 560 and 563 Lebanese individuals referred for HLA typing and possible bone marrow/kidney donation were tested for HLA-DQB1 and HLA-DRB1 alleles using the polymerase chain reaction/sequence specific priming (PCR-SSP) method.Results
Our data were compared to that of several populations with interesting common findings between the Lebanese, Jordanian, Bahraini, Saudi, Kuwaiti, Tunisian, Korean, Japanese, Thai, Irish, Bulgarian and Polish populations.Conclusion
These data about the Lebanese population are going to aid future researchers to study the relation of HLA-DQB1 and HLA-DRB1 alleles with major and common diseases in the Lebanese population and will add to the available international literature associated with these loci. In addition it will serve as a reference for the future national bone marrow registry program in our country. We also reviewed the literature for the described association between HLA-DRB1 and -DQB1 loci and different disease entities. 相似文献998.
Zaidi Mohsin Abbas El Bilali Jason Koziol Adam Gregory Ward Tonya L. Styles George Greenham Trevor J. Faiella Whitney Michelle Son Hwan Hee Wan Shen Taga Ibrahim Altosaar Illimar 《Journal of plant biochemistry and biotechnology.》2012,21(1):2-9
Applications of gene technology in agriculture, the environment and human health fields are reviewed. This case study of the intricate historical details of the development of Bt crops like cotton and rice unveils essential elements of productive funding schemes and effective multinational collaborations. Gene technology applied to pest resistance traits in global cotton is analyzed using nation-specific data from India to demonstrate ‘ricochet’ results: Regulatory approval for one crop catalyzes an ‘Enhancer Effect’ for promoting more research funding and more competitive results for other crops-in-waiting, namely rice. Just as cotton commerce promoted philanthropy in unpredictable situations like the Kreenholm dynasty of Ludwig Knoop, research budgets for pesticide and biocide technology have yielded intended effects, but several surprising unintended effects as well. Finally, the case is made for greater control of gene flow and identity preserve issues in plant biotechnology research by invoking Appellation d’Origine Contrôlée for Bt genes. 相似文献
999.
The uroporphyrinogen III synthase (UROS) enzyme (also known as hydroxymethylbilane hydrolyase) catalyzes the cyclization of
hydroxymethylbilane to uroporphyrinogen III during heme biosynthesis. A deficiency of this enzyme is associated with the very
rare Gunther''s disease or congenital erythropoietic porphyria, an autosomal recessive inborn error of metabolism. The current
study investigated the possible role of UROS (Homo sapiens [EC: 4.2.1.75; 265 aa; 1371 bp mRNA; Entrez Pubmed ref ,
NP_000366.1]) in evolution by studying the phylogenetic relationship and divergence of this gene using computational methods.
The UROS protein sequences from various taxa were retrieved from GenBank database and were compared using Clustal-W
(multiple sequence alignment) with defaults and a first-pass phylogenetic tree was built using neighbor-joining method as in
DELTA BLAST 2.2.27+ version. A total of 163 BLAST hits were found for the uroporphyrinogen III synthase query sequence and
these hits showed putative conserved domain, HemD superfamily (as on 14th Nov 2012). We then narrowed down the search by
manually deleting the proteins which were not UROS sequences and sequences belonging to phyla other than Chordata were
deleted. A repeat phylogenetic analysis of 39 taxa was performed using PhyML and TreeDyn software to confirm that UROS is a
highly conserved protein with approximately 85% conserved sequences in almost all chordate taxons emphasizing its importance
in heme synthesis. NM_000375.2相似文献
1000.
The Current Study aimed to investigate the possible role of Heparanase protein (HPSE-1, [Entrez Pubmed ref|NP_001092010.1|, heparanase isoform 1 preproprotein [Homo sapiens]) in evolution by studying the phylogenetic relationship and divergence of HPSE-1 gene using computational methods. The Human HPSE protein sequences from various species were retrieved from GenBank database and were compared using sequence alignment. Multiple sequence alignment was done using Clustal-W with defaults and phylogenetic trees for the gene were built using neighbor-joining method as in BLAST 2.2.26+ version. A total of 112 BLAST hits were found for the heparanase query sequence and these hits showed putative conserved domain, Glyco_hydro_79n superfamily. We then narrowed down the search by manually deleting the proteins which were not HPSE-1. These sequences were then subjected to phylogenetic analyses using the PhyML and TreeDyn software. Our study indicated that HPSE-1 is a conserved protein in classes Mammalia, Aves, Amphibia, Actinopterygii and Insecta emphasizing its importance in the physiology of cell membranes. Occurrence of this gene in evolution with conserved sites strengthens the role of HPSE-1 gene and helps in better understanding the biochemical processes that may lead to cancer. 相似文献