Salicylic acid induced changes on antioxidant capacity,pigments and grain yield of soybean genotypes in water deficit condition

Salicylic acid (SA) plays an important role in the regulation of plant growth and development in response to water deficit. The effect of SA (0, 0.4 and 0.8?mM) on some physiological parameters of three soybean genotypes was investigated in three irrigation schedules included (85%, 65% and 45% of field capacity) during 2014–2015. Results showed that water deficit decreased stomatal conductance, leaf area index, relative water content, membrane stability index, yield components and grain yield particularly in L17 genotype. Activities of superoxide dismutase, ascorbate peroxidase and concentration of hydrogen peroxide, proline and total protein were increased in response to water deficit as well as SA applications. SA inhibited catalase activity resulting in increased hydrogen peroxide accumulation in soybean genotypes. Application of 0.4?mM SA decreased the adverse effects of water deficit in soybean genotypes by elevation of antioxidant enzymes activity and reducing malondialdehyde formation especially in Williams genotype.     

Evaluation of silibinin on the viability, migration and adhesion of the human prostate adenocarcinoma (PC-3) cell line

Prostate cancer (PCA) is the most common cancer diagnosed in men and the second most common cause of death due to cancers after lung cancer. Metastasis of cancer cells involves multiple processes and various cytophysiological changes, including changed adhesion capability between cells and extracellular matrix (ECM) and damaged intercellular interaction. Silibinin, a naturally occurring flavonoid antioxidant found in the milk thistle, has recently been shown to have potent antiproliferative effect against various malignant cell lines. In the present study, PC-3 cells were incubated with various concentrations of silibinin for different times; then, cell cytotoxicity, cell adhesion and cell motility were assessed using MTT assay, cell-matrix adhesion assay and cell migration assay, respectively. The results showed that silibinin exerted a dose- and time-dependent inhibitory effect on the viability, motility and adhesion of highly metastatic PC-3 cells. These observations indicate that silibinin can probably inhibit metastasis in PCA.     

Microbial activity and community composition in saline and non-saline soils exposed to multiple drying and rewetting events

Background and aims

The effects of drying and rewetting (DRW) have been studied extensively in non-saline soils, but little is known about the impact of DRW in saline soils. An incubation experiment was conducted to determine the impact of 1?C3 drying and re-wetting events on soil microbial activity and community composition at different levels of electrical conductivity in the saturated soil extract (ECe) (ECe 0.7, 9.3, 17.6 dS m^?1).

Methods

A non-saline sandy loam was amended with NaCl to achieve the three EC levels 21 days prior to the first DRW; wheat straw was added 7 days prior to the first DRW. Each DRW event consisted of 1 week drying and 1 week moist (50% of water holding capacity, WHC). After the last DRW, the soils were maintained moist until the end of the incubation period (63 days after addition of the wheat straw). A control was kept moist (50% of WHC) throughout the incubation period.

Results

Respiration rates on the day after rewetting were similar after the first and the second DRW, but significantly lower after the third DRW. After the first and second DRW, respiration rates were lower at EC17.6 compared to the lower EC levels, whereas salinity had little effect on respiration rates after the third DRW or at the end of the experiment when respiration rates were low. Compared to the continuously moist treatment, respiration rates were about 50% higher on day 15 (d15) and d29. On d44, respiration rates were about 50% higher at EC9.7 than at the other two EC levels. Cumulative respiration was increased by DRW only in the treatment with one DRW and only at the two lower EC levels. Salinity affected microbial biomass and community composition in the moist soils but not in the DRW treatments. At all EC levels and all sampling dates, the community composition in the continuously moist treatment differed from that in the DRW treatments, but there were no differences among the DRW treatments.

Conclusions

Microbes in moderately saline soils may be able to utilise substrates released after multiple DRW events better than microbes in non-saline soil. However, at high EC (EC17.6), the low osmotic potential reduced microbial activity to such an extent that the microbes were not able to utilise substrate released after rewetting of dry soil.     

Enhancement of a bacterial laccase thermostability through directed mutagenesis of a surface loop

Laccases (benzenediol oxygen oxidoreductases, EC 1.10.3.2) are used in many biotechnological processes, including removal of polyphenols in beverages, decolorizing and detoxifying effluents, drug analysis and bioremediation. In the present work, we have tried to increase thermal stability of laccase from Bacillus HR03 using site directed point mutations. Glu188 was substituted with 2 positive (Lys and Arg) and one hydrophobic (Ala) residues. All mutations showed improved thermal stability. Thermal activation of laccase was also increased after introducing the mutations. Remarkably, the Glu188Lys variant showed 3-fold higher thermal activation and higher T₅₀ (5 °C) with respect to the native enzyme. Furthermore steady-state k_cat and K_m values were influenced despite the distance between the mutated position and the catalytic site. In Glu188Arg mutation, the k_cat was improved 3-fold and K_m reduced by 25%. Interestingly, all three variants showed higher stability against urea as a chemical denaturant. Structural analyses of the native and mutated variants were carried out using fluorescence and far-UV circular dichroism.     

A new species of Parapygmephorus Cross, 1965 (Acari; Heterostigmatina; Neopygmephoridae) phoretic on Halictus quadricinctus (Fabricius, 1776) (Hym.; Halictidae) from Iran

A new species of the genus Parapygmephorus Cross, 1965 (Acari: Heterostigmatina, Neopygmephoridae) is described from Northeastern Iran. A phoretic adult female of Parapygmephorus khorasanicus Hajiqanbar and Khaustov sp. n. was discovered clasping on hairs on the ventral body surface of Halictus quadricinctus (Fabricius, 1776) (Hymenoptera; Halictidae). It is the fifth representative among the known species of the genus Parapygmephorus in the world. Differentiation of new species from other species of the genus is discussed, and a key to known world species is provided.     

Apolipoprotein E genotyping in women with recurrent pregnancy loss: An in silico and experimental hybrid study

The role of apolipoprotein E gene polymorphisms in the pathogenesis of recurrent pregnancy loss remains controversial. Therefore, our objective was to investigate the association between recurrent pregnancy loss and apolipoprotein E gene polymorphisms among northwest Iranian women, and also to predict the impact of these nonsynonymous single nucleotide polymorphisms on structure and function of apolipoprotein E protein. The subjects of our current study consisted of 100 women that have had two or more consecutive idiopathic first trimester miscarriages, and one hundred healthy women from the same geographical areas were used as a control group. After DNA extraction, we used a polymerase chain reaction–restriction fragment length polymorphism to genotype of the apolipoprotein E gene. In addition, we predicted the possible effects of amino acid substitutions at codons 112 and/or 158 on the structure and function of apolipoprotein E protein using Polymorphism Phenotyping online software v2. Our results showed that the rate of apolipoprotein E ε4 carriers and the frequency of the ε4 allele in the case group were statistically and significantly higher than those in the control group (P < 0.05). Therefore, our data support the association of the Apo ε4 allele with RPL; however, in silico analysis predicted that the amino acid substitution at residue 112 (Apo ε4 allele) is a benign mutation. Accordingly, further studies are required to elucidate the mechanism(s) underlying the link between RPL pathogenesis and the Apo ε4 allele.     

Multigene Phylogenetics Reveals Temporal Diversification of Major African Malaria Vectors

The major vectors of malaria in sub-Saharan Africa belong to subgenus Cellia. Yet, phylogenetic relationships and temporal diversification among African mosquito species have not been unambiguously determined. Knowledge about vector evolutionary history is crucial for correct interpretation of genetic changes identified through comparative genomics analyses. In this study, we estimated a molecular phylogeny using 49 gene sequences for the African malaria vectors An. gambiae, An. funestus, An. nili, the Asian malaria mosquito An. stephensi, and the outgroup species Culex quinquefasciatus and Aedes aegypti. To infer the phylogeny, we identified orthologous sequences uniformly distributed approximately every 5 Mb in the five chromosomal arms. The sequences were aligned and the phylogenetic trees were inferred using maximum likelihood and neighbor-joining methods. Bayesian molecular dating using a relaxed log normal model was used to infer divergence times. Trees from individual genes agreed with each other, placing An. nili as a basal clade that diversified from the studied malaria mosquito species 47.6 million years ago (mya). Other African malaria vectors originated more recently, and independently acquired traits related to vectorial capacity. The lineage leading to An. gambiae diverged 30.4 mya, while the African vector An. funestus and the Asian vector An. stephensi were the most closely related sister taxa that split 20.8 mya. These results were supported by consistently high bootstrap values in concatenated phylogenetic trees generated individually for each chromosomal arm. Genome-wide multigene phylogenetic analysis is a useful approach for discerning historic relationships among malaria vectors, providing a framework for the correct interpretation of genomic changes across species, and comprehending the evolutionary origins of this ubiquitous and deadly insect-borne disease.     

Effect of Seasonal Variation on Adult Clinical Laboratory Parameters in Rwanda,Zambia, and Uganda: Implications for HIV Biomedical Prevention Trials

Objectives

To investigate the effect of seasonal variation on adult clinical laboratory parameters in Rwanda, Zambia, and Uganda and determine its implications for HIV prevention and other clinical trials.

Methods

Volunteers in a cross-sectional study to establish laboratory reference intervals were asked to return for a seasonal visit after the local season had changed from dry to rainy or vice versa. Volunteers had to be clinically healthy, not pregnant and negative for HIV, Hepatitis B and C, and syphilis infection at both visits. At each visit, blood was taken for measurement of hemoglobin, haematocrit, mean corpuscular volume, red blood cells, platelets, total white blood cells (WBC), neutrophils, lymphocytes, monocytes, eosinophils, basophils, CD4/CD8 T cells, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, direct bilirubin, total bilirubin, total immunoglobulin gamma, total protein, creatinine, total amylase, creatine phosphokinase and lactate dehydrogenase (LDH). Consensus dry season reference intervals were applied to rainy season values (and vice versa) and the proportion of ‘out-of-range’ values determined. Percentage differences between dry and rainy season parameter mean values were estimated.

Results

In this cohort of 903 volunteers, less than 10.0% of consensus parameter (except LDH) values in one season were “out-of-range” in the other. Twenty-two (22) percent of rainy season LDH values fell outside of the consensus dry season interval with the higher values observed in the rainy season. Variability between consensus seasonal means ranged from 0.0% (total WBC, neutrophils, monocytes, basophils, and direct bilirubin) to 40.0% (eosinophils). Within sites, the largest seasonal variations were observed for monocytes (Masaka, 11.5%), LDH (Lusaka, 21.7%), and basophils (Kigali, 22.2%).

Conclusions

Seasonality had minimal impact on adult clinical laboratory parameter values in Rwanda, Zambia, and Uganda. Seasonal variation may not be an important factor in the evaluation of adult clinical laboratory parameters in HIV prevention and other clinical trials in these countries.