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51.
Bovine leukemia virus (BLV), the causative agent of enzootic bovine leukosis, is an exogenous, B lymphotropic retrovirus belonging to the Retroviridae family that induces persistent lymphocytosis in cattle and sheep. PCR has proven to be particularly suitable for investigating herds of cattle with a very low incidence of BLV infection and for clarifying doubtful serological results obtained by immunodiffusion or ELISA. The native Iranian and Russian cattle have a series of valuable traits that discriminate them as unique breeds that are well able to compete with western analogues. However, their gene pools have not been analyzed with molecular markers, including detection of BLV by PCR. Two pairs of primers were used: gag1 and gag2, and pol1 and pol2, which encompass 347- and 599-bp fragments of the BLV gene, respectively. Sixty-five Iranian Sistani, 120 Yaroslavl, 50 Mongolian, and 35 Black Pied cows were investigated. Among these 270 animals, we obtained 42 positive and 15 doubtful results in the first PCR. The second PCR was very effective in increasing BLV test reliability data to support detection of BLV.  相似文献   
52.
In order to investigate on inheritance and gene action for resistance to yellow rust, the resistant line C.B227 was crossed with the susceptible variety Avocet. Parents (P1 and P2) and the resulting F1, F2 and F3 generations were planted in a randomised complete block design with two replications in the field. The plants were inoculated with 70E0A+ pathotype of yellow rust in the research station of Gharakhil, Iran, and evaluated for resistance at adult plant stage. Disease severity and infection type of flag leaf were recorded for each single plant and final coefficient of infection was calculated. The results of weighted ANOVA indicated that the difference among the generations was significant (p?<?0.01) for the trait final infection type. Generation mean analysis showed that dominant effect was more important than additive one. The degree of dominance indicated the presence of complete dominance. Additive, dominance and epistasic additive?×?additive [i] effects were important in genetic control of resistance. The results of generation variance analysis were consistent with generation mean analysis.  相似文献   
53.
54.

Objective

Post exposure prophylaxis using one of the WHO-approved vaccines is the method of choice for preventing rabies. Abnormal immune function in patients with some specific medical conditions, such as pregnancy, chronic hepatitis B virus infection, different types of cancers like lymphoma, diabetes I and II, corticosteroid consumption by patients with rheumatoid arthritis and lupus erythematosus, could impair the immunologic response to various vaccines. The immune response to rabies vaccination has never been examined in patients with any of these described medical conditions. This study purposed to evaluate the neutralyzing antibody response after vaccination with purified Vero cell rabies vaccine (PVRV) according to the WHO-recommended Post–Exposure Prophylaxis (PEP) "ESSEN" regimen.

Methods

Thirty healthy volunteers and 50 volunteers with different medical conditions who were exposed to a suspected rabid animal in the 2nd or 3rd category of exposure received 5 doses of PVRV under the ESSEN protocol. Three blood samples were collected on days 0 (before the first dose), 14, and 35. The anti-rabies antibody titer was measured using the Rapid Fluorescent Foci Inhibition Test (RFFIT) and an ELISA Bio-Rad, Platelia, Rabies II kit.

Results

All subjects reached NAb titers above 0.5 IU/ml by day 14 after vaccination. On day 35 (1 week after receiving the last rabies vaccine), anti-rabies antibodies were in the protective level (>0.5 IU/ml) in both groups. There was no statistically significant difference in anti-rabies antibody response due to the type of exposure (category 2 or 3), and successful seroconversion was confirmed in both groups.

Conclusion

In conclusion, the ESSEN protocol using the PVRV vaccine is sufficient for rabies prophylaxis in patients with specific medical conditions.  相似文献   
55.
l -Asparaginases hydrolyzing plasma l -asparagine and l -glutamine has attracted tremendous attention in recent years owing to remarkable anticancer properties. This enzyme is efficiently used for acute lymphoblastic leukemia (ALL) and lymphosarcoma and emerged against ALL in children, neoplasia, and some other malignancies. Cancer cells reduce the expression of l -asparaginase leading to their elimination. The l -asparaginase anticancerous application approach has made incredible breakthrough in the field of modern oncology through depletion of plasma l -asparagine to inhibit the cancer cells growth; particularly among children. High level of l -asparaginase enzyme production by Escherichia coli, Erwinia species, Streptomyces, and Bacillus subtilis species is highly desirable as bacterial alternative enzyme sources for anticancer therapy. Thermal or harsh conditions stability of those from the two latter bacterial species is considerable. Some enzymes from marine bacteria have conferred stability in adverse conditions being more advantageous in cancer therapy. Several side effects exerted by l -asparaginases such as hypersensitivity should be hindered or decreased through alternative therapies or use of immune-suppressor drugs. The l -asparaginase from Erwinia species has displayed remarkable traits in children with this regard. Noticeably, Erwinia chrysanthemi l -asparaginase exhibited negligible glutaminase activity representing a promising efficiency mitigating related side effects. Application of software such as RSM would optimize conditions for higher levels of enzyme production. Additionally, genetic recombination of the encoding gene would indisputably help improving enzyme traits. Furthermore, the possibility of anticancer combination therapy using two or more l -asparaginases from various sources is plausible in future studies to achieve better therapeutic outcomes with lower side effects.  相似文献   
56.
Among various factors influencing mood disorders, the impact of micronutrient deficiencies has attracted a great attention. Zinc deficiency is considered to play a crucial role in the onset and progression of mood disorders in different stages of life. The main objective of this study was to assess the correlation between serum zinc levels and mood disorders in high school female students. This cross-sectional study was conducted on a random sample of 100 representative high school female students. The participants completed 24-h food recall questionnaires to assess the daily zinc intakes. Serum zinc status was assessed using flame atomic absorption spectrometry, and zinc deficiency was defined accordingly. Mood disorders were estimated by calculating the sum of two test scores including Beck’s depression inventory (BDI) and hospital anxiety depression scale (HADS) tests. General linear model (GLM) and Pearson’s regression test were applied to show the correlation of serum zinc levels and mood disorder scores and the correlation between zinc serum levels and BDI scores, respectively. Dietary zinc intake was higher in subjects with normal zinc concentrations than that of zinc-deficient group (p = 0.001). Serum zinc levels were inversely correlated with BDI and HADS scores (p < 0.05). Each 10 μg/dL increment in serum zinc levels led to 0.3 and 0.01 decrease in depression and anxiety scores, respectively (p < 0.05). Serum zinc levels were inversely correlated with mood disorders including depression and anxiety in adolescent female students. Increasing serum levels of zinc in female students could improve their mood disorders.  相似文献   
57.
A novel peptide, PNP (Pseudocerastes persicus natriuretic peptide), was isolated from the venom of the Iranian viper P. persicus. Amino acid sequencing revealed that the 37-residue peptide belongs to the family of natriuretic peptides. The physiological effects of intra-venously PNP infused into anesthetized rats on urine flow, sodium excretion and blood pressure were comparable to those of atrial natriuretic peptide (ANP). In PC12 cells that were treated with either PNP, ANP, or C-type natriuretic peptide, PNP induced a similar cGMP response as ANP. Since PC12 cells only express the natriuretic peptide receptor (NPR)-A receptor we conclude that PNP binds to the NPR-A receptor. The solution conformation of PNP was characterized using (1)H nuclear magnetic resonance spectroscopy and indicates a high degree of conformational flexibility.  相似文献   
58.
The properties (or labels) of nodes in networks can often be predicted based on their proximity and their connections to other labeled nodes. So-called “label propagation algorithms” predict the labels of unlabeled nodes by propagating information about local label density iteratively through the network. These algorithms are fast, simple and scale to large networks but nonetheless regularly perform better than slower and much more complex algorithms on benchmark problems. We show here, however, that these algorithms have an intrinsic limitation that prevents them from adapting to some common patterns of network node labeling; we introduce a new algorithm, 3Prop, that retains all their advantages but is much more adaptive. As we show, 3Prop performs very well on node labeling problems ill-suited to label propagation, including predicting gene function in protein and genetic interaction networks and gender in friendship networks, and also performs slightly better on problems already well-suited to label propagation such as labeling blogs and patents based on their citation networks. 3Prop gains its adaptability by assigning separate weights to label information from different steps of the propagation. Surprisingly, we found that for many networks, the third iteration of label propagation receives a negative weight.

Availability

The code is available from the authors by request.  相似文献   
59.
Due to the constant increasing of bacterial resistance against known antibiotics, it is now necessary to find new sources of antimicrobials including the marine environment. The aim of this study was to evaluate antimicrobial activity of bacterial strains isolated from different coastal regions of the Caspian Sea and to provide phylogenetic analyses of antibiotic producing strains. Water samples collected from the Caspian Sea were serially diluted and plated on selective media. Isolates were tested against a panel of reference strains (Streptococcus pyogenes, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa) by microbial antagonism and disc diffusion assay. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) method was also employed to produce a phylogenetic tree based on 16S rDNA sequences. Amongst 162 isolates, 8 strains (4.93%) showed antibacterial activity. Isolated bacteria displayed more activity against gram-positive bacteria than gram-negative bacteria. Moreover, the 16S sequences obtained for the 8 selected strains were compared using a BLAST algorithm and allowed us to determine the strains genus as followed: Bacillus (RS28, RS54, RS56, RS82, RS116, and NS53), Brevundimonas (RS32), and Arthrobacter (NS25). The findings of the present study recommend that culturally marine bacteria collected from the Caspian Sea might be a potent source of novel bioactive compounds such as antibiotics.  相似文献   
60.
Undecaprenyl Pyrophosphate Synthase (UPPS) is an enzyme critical to the production of complex polysaccharides in bacteria, as it produces the crucial bactoprenol scaffold on which these materials are assembled. Methods to characterize the systems associated with polysaccharide production are non-trivial, in part due to the lack of chemical tools to investigate their assembly. In this report, we develop a new fluorescent tool using UPPS to incorporate a powerful fluorescent anthranilamide moiety into bactoprenol. The activity of this analogue in polysaccharide biosynthesis is then tested with the initiating hexose-1-phosphate transferases involved in Capsular Polysaccharide A biosynthesis in the symbiont Bacteroides fragilis and the asparagine-linked glycosylation system of the pathogenic Campylobacter jejuni. In addition, it is shown that the UPPS used to make this probe is not specific for E-configured isoprenoid substrates and that elongation by UPPS is required for activity with the downstream enzymes.  相似文献   
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