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91.
Toxoplasma gondii ME49 is an obligatory intracellular apicomplexa parasite that causes toxoplasmosis in humans, domesticated and wild animals. Waterborne outbreaks of acute toxoplasmosis worldwide reinforce the transmission of Toxoplasma gondii ME49 to humans through contaminated water and may have a greater epidemiological impact than previously believed. In the quest for drug and vaccine target identification subtractive genomics involving subtraction between the host and pathogen genome has been implemented for enlisting essential pathogen specific proteins. Using this approach, our analysis on both human and Toxoplasma gondii ME49 reveals that out of 7987 protein coding sequences of the pathogen, 950 represent essential non human-homologous proteins. Subcellular localization prediction & comparative-biochemical pathway analysis of these essential proteins gives a list of apicoplast-associated proteins having unique pathogen-specific metabolic pathway. These apicoplast-associated enzymes involved in fatty acid biosynthesis pathway of Toxoplasma gondii ME49, may be used as potential drug targets, as the pathway is vital for the protozoan's survival. Structure prediction of drug target proteins was done using fold based recognition method. Screening of the functional inhibitors against these novel targets may result in discovery of novel therapeutic compounds that can be effective against Toxoplasma gondii ME49. ABBREVIATIONS: DEG - Database of Essential Gene, KEGG - Kyoto Encyclopaedia of Genes and Genomes, KAAS - KEGG Automated Annotation Server, PFP - Protein Function Prediction, COG - Cluster of Orthologous Genes.  相似文献   
92.
Traditionally, drugs are discovered by testing compounds synthesized in time consuming multi-step processes against a battery of invivo biological screens. Promising compounds are then further studied in development, where their pharmacokinetic properties, metabolism and potential toxicity were investigated. Here, we present a study on herbal lead compounds and their potential binding affinity to the effectors molecules of major disease like Prostate Cancer. Clinical studies demonstrate a positive correlation between the extent of 5-α reductase type 2 (isoform 2) and malignant progression of precancerous lesions in prostate. Therefore, identification of effective, well-tolerated 5-α reductase inhibitors represents a rational chemo preventive strategy. This study has investigated the effects of naturally occurring nonprotein compounds berberine and monocaffeyltartaric acid that inhibits 5-α reductase type 2. Our results reveal that these compounds use less energy to bind to 5-α reductase and inhibit its activity. Their high ligand binding affinity to 5-α reductase introduces the prospect for their use in chemopreventive applications. In addition, they are freely available natural compounds that can be safely used to prevent prostate cancer.  相似文献   
93.
CagA is a major virulence factor of Helicobacter pylori involved in host cell modulation. The C-terminal part of CagA containing the EPIYA motifs is highly variable and is important for the biological activity of the protein. The aim of this study was consideration of the changes in cagA tyrosine phosphorylation motifs (TPMs) of H. pylori. A set of 302 H. pylori DNA samples from the Iranian population from 2006 to 2011 was selected for the proposed study. The cagA gene and its TPMs were assessed by using polymerase chain reaction (PCR) and specific primers. The prevalence of the cagA gene in our study ranged from 91.43 % to 97.06 % (with an average of 95.03 %). Out of the cagA-positive samples, the prevalence of TPMs A and B increased from 12.5 % and 23.44 % to 71.2 % and 63.63 %, respectively. Also, the prevalence of samples infected with Western and East Asian types of H. pylori ranged from 64.06 % to 5.73 % for the Western type and 17.19 % to 51.59 % for the East Asian type. Overall, our results showed a high prevalence of the cagA gene. Also, it seems that cagA TPMs of H. pylori is undergoing a change from the Western type to the East Asian type in Iran.  相似文献   
94.

In this paper, the idea of square fractal geometry has been utilized to introduce a tunable wideband graphene-based perfect plasmonic absorber in the near-infrared region. It consists of a MgF2 layer and an array of gold squares fractal loaded on a graphene layer. In the designed absorber a single layer of graphene has been used instead of multilayered graphene structures. The structure is polarization-insensitive under normal incidence due to the geometric symmetry. The absorption and bandwidth of the structure are almost insensitive to the incident angle up to 15° and 45° for TE and TM polarizations, respectively. Moreover, by choosing appropriate structural parameters, the resonance wavelength of the desired plasmonic absorber can be controlled. The absorption of the introduced structure can be tuned by changing the chemical potential of the graphene. Therefore, the proposed fractal absorber can act as switch and inverter at λ = 1995 nm. Furthermore, the equivalent circuit model of the absorber has been derived to confirm the validity of the simulation results. The superiorities of our fractal absorber are wide full-width at half-maximum of 406 nm, multi-applicant, perfect absorption, and fabrication feasibility due to the simple structure with the maximum absorption tolerance error of 5.12%.

  相似文献   
95.
International Journal of Peptide Research and Therapeutics - Klebsiella pneumoniae is one of the major causes of nosocomial infections worldwide which can cause several diseases in children and...  相似文献   
96.
Molecular Biology Reports - The changing epidemiology and decreasing susceptibility to first-line antibiotics, such as vancomycin and linezolid, leave clinicians with few therapeutic options for...  相似文献   
97.
The geographical distribution and ecological preferences of Haemaphysalis in domestic animals in Iran were studied 4 times a year from April 2003 to March 2005. A total of 1,622 ixodid tick specimens were collected from 3 different zones. Among them, 108 (6.7%) Haemaphysalis ticks, consisting of 6 species, were identified; H. punctata (3.4%), H. parva (0.5%), H. sulcata (0.6%), H. choldokovskyi (1.7%), H. concinna (0.06%) and Haemaphysalis sp. (0.6%). H. punctata was the most abundant species, whereas H. concinna was the rarest species collected in humid and sub-humid zones on cattle, sheep and goats. H. choldokovskyi was principally collected from sheep and goats grazed in cold mountainous areas. The infested areas consisted of Caspian Sea (Guilan, Mazandaran, Golestan, and central provinces), mountainous (Azarbaiejan, Ardebil, Kohgilouyeh, and Kordestan) and semi-dessert (Khorasan, Semnan, Kerman, Sistan, and Baluchestan) zones. The Caspian Sea zone (23.6%) was the most highly infested region. The results show that various species of Haemaphysalis ticks infest domestic ruminants in Iran and each tick species show characteristic geographical distributions.  相似文献   
98.
99.
Blast caused by the fungus Magnaporthae grisea (Herbert) Borr. (anamorphe Pyricularia oryza Cav.) is a serious disease of rice (Oryza sativa L.). One method to overcome this disease is to develop disease resistant cultivars. Due to the genetic plasticity in the pathogen genome, there is a continuous threat to the effectiveness of the developed cultivars. Additional studies of the genetics of resistance, virulence stability and functional genomics are required to accelerate research into understanding the molecular basis of blast disease resistance. In this study, individual plants of the F3 population derived from Pongsu Seribu 2 and Mahsuri were used for pathogenesis assays and inheritance studies of blast resistance. The study was performed with two of the most virulent Malaysian M. grisea pathotypes: P7.2 and P5.0. For blast screening, plants were scored based on the IRRI Standard Evaluation System (SES). F3 populations showed a segregation ratio of 3R:1S for pathotype P7.2, indicating that resistance to this pathotype is likely controlled by a single nuclear gene. Chi‐square analysis showed that the F3 families segregated in a 15R:1S ratio for pathotype P5.0. Therefore, locus interactions or epitasis of blast resistance occur against pathotype P5.0 in the F3 population derived from Pongsu Seribu 2 and Mahsuri. This can be explained by the presence of two independent dominant genes that when present simultaneously, provide resistance to the M. gresia pathotype P5.0. These results indicated that blast resistance in rice is due to the combined effects of multiple loci with major and minor effects. The genetic data generated here will be useful in the breeding of local cultivars for resistance to field blast. The methodology reported here will facilitate the mapping of genes and quantitative trait loci (QTLs) underlying the blast resistance trait.  相似文献   
100.

Background

Cardiovascular diseases are among somatic disorders and psychological factors affect their onset, exacerbation, and treatment. This study was conducted on the hospitalized patients who had heart failure with and without depression. The study criteria was to evaluate the effect of self-care education on awareness, attitude, and adherence to self-care behaviors on these patients.

Materials and Methods

In this quasi-experimental study, seventy patients with heart failure that met the inclusion criteria were recruited through purposive sampling method. They were assigned in to two equal size groups regarding their depression status. First, the eligible patients were selected; then Beck Depression Inventory was done on the patients followed by examination by the clinical psychologist. Patients with average and higher scores were classified in the depressed group and others who got lower than average scores were classified as the non -depressed group. A questionnaire containing items related to awareness, attitude, and adherence to self-care behaviors was used to collect the data. First, self-care behavior was determined and then a four-sessions of educational intervention were held individually for both groups. The second round of questionnaires were completed at patients’ home twelve weeks after the discharge. The Collected data was analyzed using independent-samples and paired-sample t tests, Chi square, and statistical analysis of covariance (ANCOVA) tests through SPSS (version 21, SPSS Inc., Chicago, IL, USA).

Results

After the educational sessions, the statistical analysis showed significant differences in the mean scores of awareness, attitude, and adherence to self-care behaviors between the two groups (P<0.0001).

Conclusion

Self-care behavior education had lower effects on the depressed patients with heart failure. Therefore, before providing education for these patients, it is necessary to consider their psychological problems such as depression.  相似文献   
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