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1.
Molecular Biology Reports - Both extreme usage of water in agriculture i.e., drought and flooding affect physiological and growth aspects of the plant as well as gene expression undertaken in water...  相似文献   
2.
The aim is to explore the treatment effect of coronary artery disease (CAD) and hypertension on plasma levels of renalase activity and also the possible association of renalase rs10887800 gene polymorphism with CAD and hypertension. A total of 286 patients who received coronary angiography were included in the study. Subjects were divided into four groups including (1) hypertensive with no CAD (H-Tens, n = 60); (2) CAD with hypertension (CAD + H-Tens, n = 71); (3) CAD with no hypertension (CAD, n = 61); and (4) nonhypertensive with no CAD as a control group (Con, n = 69). The plasma renalase activity was measured using the Amplex Red Monoamine Oxidase Assay Kit. Renalase rs10887800 single-nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Atorvastatin (P = 0.005), losartan (P < 0.001), and captopril (P = 0.001) were administered significantly more in case groups compared with the Con group. Significant higher and lower levels of renalase activity were observed in H-Tens and CAD patients compared with control subjects (P < 0.001 for both comparisons). Furthermore, no significant differences were obtained in the risk or protective effects of renalase rs10887800 SNP against hypertension and/or CAD in both recessive and dominant genetic models (P > 0.05). According to the findings of the present study, atorvastatin and losartan therapy assumes considerable significance in alleviating hypertension, but not CAD, by increasing the renalase activity. Furthermore, it was found that renalase rs10887800 is less likely a predisposing factor for susceptibility to hypertension and/or CAD in an Iranian southeast population.  相似文献   
3.
The extracellular proteases of Aspergillus nidulans are produced in response to limitation of carbon, nitrogen, or sulfur, even in the absence of exogenous protein. Mutations in the A. nidulans xprF and xprG genes have been shown to result in elevated levels of extracellular protease in response to carbon limitation. The xprF gene was isolated and sequence analysis indicates that it encodes a 615-amino-acid protein, which represents a new type of fungal hexokinase or hexokinase-like protein. In addition to their catalytic role, hexokinases are thought to be involved in triggering carbon catabolite repression. Sequence analysis of the xprF1 and xprF2 alleles showed that both alleles contain nonsense mutations. No loss of glucose or fructose phosphorylating activity was detected in xprF1 or xprF2 mutants. There are two possible explanations for this observation: (1) the xprF gene may encode a minor hexokinase or (2) the xprF gene may encode a protein with no hexose phosphorylating activity. Genetic evidence suggests that the xprF and xprG genes are involved in the same regulatory pathway. Support for this hypothesis was provided by the identification of a new class of xprG(-) mutation that suppresses the xprF1 mutation and results in a protease-deficient phenotype.  相似文献   
4.
Peptide-based vaccines are attractive approaches for cancer immunotherapy; but the success of these vaccines in clinical trials have been limited. Our goal is to improve immune responses and anti-tumor effects against a synthetic, multi-epitope, long peptide from rat Her2/neu (rHer2/neu) using the help of CD4+ T cells and appropriate adjuvant in a mouse tumor model. Female BALB/c mice were vaccinated with P5+435 multi-epitope long peptide that presents epitopes for cytotoxic T lymphocytes (CTL) in combination with a universal Pan DR epitope (PADRE) or CpG-oligodeoxynucleotides (CpG-ODNs) as a Toll-like receptor agonist adjuvant. The results show that vaccination with the multi-epitope long peptide in combination with the PADRE peptide and CpG-ODN induced expansion of subpopulations of CD4+ and CD8+ cells producing IFN-γ, the average tumor size in the vaccinated mice was less than that of the other groups, and tumor growth was inhibited in 40% of the mice in the vaccinated group. The mean survival time was 82.6 ± 1.25 days in mice vaccinated with P5+435 + CpG+ PADRE. Our results demonstrate that inclusion of PADRE and CpG with the peptide vaccine enhanced significant tumor specific-immune responses in vaccinated mice.  相似文献   
5.
CYLD is a tumour‐suppressor gene that is mutated in a benign skin tumour syndrome called cylindromatosis. The CYLD gene product is a deubiquitinating enzyme that was shown to regulate cell proliferation, cell survival and inflammatory responses, mainly through inhibiting NF‐κB signalling. Here we show that CYLD controls cell growth and division at the G1/S‐phase as well as cytokinesis by associating with α‐tubulin and microtubules through its CAP‐Gly domains. Translocation of activated CYLD to the perinuclear region of the cell is achieved by an inhibitory interaction of CYLD with histone deacetylase‐6 (HDAC6) leading to an increase in the levels of acetylated α‐tubulin around the nucleus. This facilitates the interaction of CYLD with Bcl‐3, leading to a significant delay in the G1‐to‐S‐phase transition. Finally, CYLD also interacts with HDAC6 in the midbody where it regulates the rate of cytokinesis in a deubiquitinase‐independent manner. Altogether these results identify a mechanism by which CYLD regulates cell proliferation at distinct cell‐cycle phases.  相似文献   
6.
PPO (protoporphyrinogen IX oxidase) catalyses the flavin-dependent six-electron oxidation of protogen (protoporphyrinogen IX) to form proto (protoporphyrin IX), a crucial step in haem and chlorophyll biosynthesis. The apparent K(m) value for wild-type tobacco PPO2 (mitochondrial PPO) was 1.17 muM, with a V(max) of 4.27 muM.min(-1).mg(-1) and a catalytic activity k(cat) of 6.0 s(-1). Amino acid residues that appear important for substrate binding in a crystal structure-based model of the substrate docked in the active site were interrogated by site-directed mutagenesis. PPO2 variant F392H did not reveal detectable enzyme activity indicating an important role of Phe(392) in substrate ring A stacking. Mutations of Leu(356), Leu(372) and Arg(98) increased k(cat) values up to 100-fold, indicating that the native residues are not essential for establishing an orientation of the substrate conductive to catalysis. Increased K(m) values of these PPO2 variants from 2- to 100-fold suggest that these residues are involved in, but not essential to, substrate binding via rings B and C. Moreover, one prominent structural constellation of human PPO causing the disease variegate porphyria (N67W/S374D) was successfully transferred into the tobacco PPO2 background. Therefore tobacco PPO2 represents a useful model system for the understanding of the structure-function relationship underlying detrimental human enzyme defects.  相似文献   
7.
A new species of the genus Crassolabium, Crassolabium persicumsp. n., collected from Arasbaran rangelands of Iran, is described and illustrated. It is characterized by its body 1.92-2.40 mm long, lip region offset by constriction and 17-19 μm wide, odontostyle 16-19 μm long with aperture occupying less than one-third (27-30%) its length, neck 428-690 μm long, pharyngeal expansion 369-390 μm long or occupying 54-56% of total neck length, female genital system amphidelphic, uterus bipartite and 162-218 μm long or 2.3-3.5 times as long as body diameter, pars refringens vaginae well developed, V = 54-57.5, vulva longitudinal, prerectum bearing a blind sac, tail conical with rounded tip to conoid (25-36 μm, c=60-69, c'=0.5-0.9), spicules 68-72 μm long, precloacal pair of supplements far (22-27 μm) from cloacal aperture, and 13-17 shortly spaced ventromedian supplements with hiatus. The new taxon is compared in depth to its relatives in Crassolabium as well as other similar species of Aporcelaimellus and Amblydorylaimus.  相似文献   
8.

Background

The objective of this study is to determine the effect of a consultation model, Beliefs, Attitudes, Subjective Norms and Enabling Factors (BASNEF), and the counselling steps using GATHER-Greet clients, Ask clients about themselves, Tell clients about their choices, Help clients choose, Explain what to do, and Return for follow-up-on the continuation rates of exclusive breastfeeding in mothers of premature infants.

Methods

This is a randomized controlled clinical trial carried out on 124 mothers with premature infants hospitalized in Fatemieh Hospital, city of Hamadan, in 2014. Participants were randomly assigned to either the intervention or control groups. The initial demographic questionnaire carried out in both groups included three questions about the continuation of exclusive breastfeeding, BASNEF, a checklist related to the lactation performance documented by mothers and the weight gain of their infants. Five breastfeeding consultation sessions based on the BASNEF model and counselling steps using GATHER, were held for the mothers in the intervention group for five consecutive days. Then follow-up weight gain and the questionnaire completion were performed in both groups at 1, 2, 3 and 4 months after the intervention.

Results

Baseline characteristics were similar in the two groups. There were no significant differences between both groups in the rate of exclusive breastfeeding, lactation performance and infant weight at baseline. The intervention group had significantly higher rates of exclusive breastfeeding, 72.6% versus the control group of 16.1%, at the end of the 4 month follow-up. Also the intervention group had significantly higher mean scores of lactation performance (8.62?±?2.08 vs 6.40?±?1.84 in the control group) and infant weight (5694.80?±?779.43 vs 4760.17?±?859.12 in the control group) at the end of the 4 month follow-up.

Conclusion

Breastfeeding consultation of mothers based on the BASNEF model and using GATHER counselling steps increased the rate of exclusive breastfeeding, lactation performance and weight gain of premature infants. Therefore, breastfeeding counselling sessions are recommended for all mothers of premature infants.

Trial registration

Iranian Registry of Clinical Trials number IRCT2014111013405N6 and date registered, January 5, 2015.
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9.
10.
Kojic acid is widely used to inhibit the browning effect of tyrosinase in cosmetic and food industries. In this work, synthesis of kojic monooleate ester (KMO) was carried out using lipase-catalysed esterification of kojic acid and oleic acid in a solvent-free system. Response Surface Methodology (RSM) based on central composite rotatable design (CCRD) was used to optimise the main important reaction variables, such as enzyme amount, reaction temperature, substrate molar ratio, and reaction time along with immobilised lipase from Candida Antarctica (Novozym 435) as a biocatalyst. The RSM data indicated that the reaction temperature was less significant in comparison to other factors for the production of a KMO ester. By using this statistical analysis, a quadratic model was developed in order to correlate the preparation variable to the response (reaction yield). The optimum conditions for the enzymatic synthesis of KMO were as follows: an enzyme amount of 2.0 wt%, reaction temperature of 83.69°C, substrate molar ratio of 1:2.37 (mmole kojic acid:oleic acid) and a reaction time of 300.0 min. Under these conditions, the actual yield percentage obtained was 42.09%, which is comparably well with the maximum predicted value of 44.46%. Under the optimal conditions, Novozym 435 could be reused for 5 cycles for KMO production percentage yield of at least 40%. The results demonstrated that statistical analysis using RSM can be used efficiently to optimise the production of a KMO ester. Moreover, the optimum conditions obtained can be applied to scale-up the process and minimise the cost.  相似文献   
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