Gene flow in malaria vector Anopheles stephensi (Diptera: Culicidae) across the Aravalli Hills in North-west India

The population structure of An. stephensi in North-west India was studied to assess the impact of the Aravalli Hills, as a barrier to gene flow using microsatellite markers. Large and significant genetic differentiation was found along the sides of, as well as across, the Aravalli Hills as the mean F_ST and R_ST on west vs. east of the Aravalli Hills were 0.213, 0.112 and 0.179, 0.056, respectively. Similarly, across the hills, mean values of F_ST and R_ST were 0.100 and 0.094, respectively. Genetic diversity on both sides did not vary significantly. The F_ST values were more sensitive than R_ST values, indicating that genetic drift might have caused genetic differentiation between populations. A positive correlation (r = 0.0149 and 0.157, respective to F_ST and R_ST) was found between genetic differentiations and geographic distances irrespective of the hills. Low level of gene flow was found along both sides (Nm = 0.92 and 0.14; west vs. east of Aravalli Hills, respectively) as compared to across the Aravalli Hills (Nm = 2.25). It was found that the Aravalli Hills are not working as an effective barrier to gene flow for An. Stephensi, maybe because of the low average height and discontinuous hills, however, the distance is playing a major role for differentiation between populations due to active mode of dispersal of An. stephensi mosquitoes which have a short flight range. All this information should help draw the strategies for genetic control of mosquitoes using transgenic mosquitoes.     

An antibiotic,heavy metal resistant and halotolerant <Emphasis Type="Italic">Bacillus cereus</Emphasis> SIU1 and its thermoalkaline protease

Background  

Many workers have reported halotolerant bacteria from saline conditions capable of protease production. However, antibiotic resistance and heavy metal tolerance pattern of such organisms is not documented very well. Similarly, only a few researchers have reported the pattern of pH change of fermentation medium during the course of protease production. In this study, we have isolated a halotolerant Bacillus cereus SIU1 strain from a non-saline environment and studied its antibiotic and heavy metal resistance pattern. The isolate produces a thermoalkaline protease and changes the medium pH during the course of fermentation. Thermostability of protease was also studied for 30 min.     

Thyroid Hormone Treatments Differentially Affect the Temperature Kinetics Properties of FoF1 ATPase and Succinate Oxidase as well as the Lipid/Phospholipid Profiles of Rat Kidney Mitochondria: A Correlative Study

Effect of thyroidectomy (Tx) and subsequent treatment with 3,5,3′-triiodo-l-thyronine (T₃) or replacement therapy (T_R) with T₃ + l-thyroxine (T₄) on the temperature kinetics properties of FoF₁ adenosine triphosphatase (ATPase, ATP synthase, H⁺-translocating ATP synthase EC 3.6.3.14) and succinate oxidase (SO) and on the lipid/phospholipid makeup of rat kidney mitochondria were examined. Tx lowered ATPase activity, which T₃ treatment restored. SO activity was unchanged in Tx but decreased further by T₃ treatment. T_R restored both activities. The energies of ATPase activation in the high and low temperature ranges (E _H and E _L) increased in the Tx and T₃ animals with decrease in phase transition temperature (Tt). T_R restored E _H and E _L but not Tt to euthyroid levels. E _H and E _L of SO decreased in Tx animals. T₃ and T_R restored E _H whereas E _L was restored only in the T_R group; Tt increased in both groups. Total phospholipid and cholesterol contents decreased significantly in Tx and T₃-treated animals. In Tx animals, sphingomyelin (SPM) and phosphatidylcholine (PC) components decreased, while phosphatidylserine (PS) and diphosphatidylglycerol components increased. T₃ and T_R treatments caused decreases in SPM, phosphatidylinositol and PS. PC and phosphatidylethanolamine (PE) increased in the T₃ group. T_R resulted in increased lysophospolipids and PE. Changes in kinetic parameters of the two enzymes were differently correlated with specific phospholipid components. Both T₃ and T_R regimens were unable to restore normal membrane structure-function relationships.     

Chiral recyclable dimeric and polymeric Cr(III) salen complexes catalyzed aminolytic kinetic resolution of trans-aromatic epoxides under microwave irradiation

Aminolytic kinetic resolution (AKR) of trans-stilbene oxide and trans-beta-methyl styrene oxide proceeded smoothly under microwave irradiation using chiral dimeric and polymeric Cr(III) salen complexes as efficient catalysts, giving regio-, diastereo-, and enantioselective anti-beta-amino alcohols in high yields (49%) and chiral purity (ee up to 94%) in case of 4-methylaniline within 2 min. The kinetic resolution system is approximately five times faster than traditional oil bath heating at 70 degrees C and 420 times faster than the reaction conducted at room temperature with concomitant recovery of respective chirally enriched epoxides (ee, 92%) in excellent yields (up to 48%). The catalyst 1 worked well in terms of enantioselectivity than the catalyst 2, but both the catalysts were easily recovered and reused five times with the retention of its efficiency.     

Proteomic analysis of maternal serum in down syndrome: identification of novel protein biomarkers

Down syndrome (DS) is the most prevalent chromosomal disorder, accounting for significant morbidity and mortality. Definitive diagnosis requires invasive amniocentesis, and current maternal serum-based testing requires a false-positive rate of about 5% to detect 85% of affected pregnancies. We have performed a comprehensive proteomic analysis to identify potential serum biomarkers to detect DS. First- and second-trimester maternal serum samples of DS and gestational age-matched controls were analyzed using multiple, complementary proteomic approaches, including fluorescence 2-dimensional gel electrophoresis (2D-DIGE), 2-dimensional liquid chromatography-chromatofocusing (2D-CF), multidimensional protein identification technology (MudPIT; LC/LC-MS/MS), and MALDI-TOF-MS peptide profiling. In total, 28 and 26 proteins were differentially present in first- and second-trimester samples, respectively. Of these, 19 were specific for the first trimester and 16 for the second trimester, and 10 were differentially present in both trimesters. Analysis of MALDI-TOF-MS peptide profiles with pattern-recognition software also discriminated between DS and controls in both trimesters, with an average recognition capability approaching 96%. A majority of the biomarkers identified are serum glycoproteins that may play a role in cellular differentiation and growth of fetus. Further characterization and quantification of these markers in a larger cohort of subjects may provide the basis for new tests for improved DS screening.     

Evolution of an intermediate C4 photosynthesis in the non-foliar tissues of the Poaceae

Photosynthesis Research - Carbon concentrating mechanisms (CCMs) in plants are abaptive features that have evolved to sustain plant growth in unfavorable environments, especially at low atmospheric...     

Taxonomic importance of seed macro‐ and micro‐morphology in Abelmoschus (Malvaceae)

Seed morphology of Abelmoschus is known to be variable, but patterns of variation have never been critically studied. We studied seed macro‐ and micro‐morphological characters, including seed shape/size, seed coat pattern and trichome density/structure in multiple samples to evaluate the taxonomic significance of seed characters. Among the studied characters, seed shape and trichome structure were found to have major taxonomic importance and proved to be valuable characters for separating taxa. Two main seed types were present: seeds with deciduous trichomes and seeds with persistent trichomes. These characters offer significant evidence to the distinctness of certain species (A. esculentus, A. moschatus subsp. moschatus, A. moschatus subsp. tuberosus, A. crinitus and A. angulosus). Further, our results indicate that A. moschatus subsp. tuberosus should be maintained as a separate subspecies while A. manihot subsp. tetraphyllus var. pungens may be merged in A. angulosus. No significant intraspecific variation was observed, except in A. esculentus. We conclude that seed coat sculpturing and seed trichomes do indeed provide stable and diagnostic characters for many morphologically closely related taxa of Abelmoschus and that LM/SEM techniques can be useful in solving systematic problems and management of Abelmoschus genetic resources.     

基于微卫星标记的印度中部Madhya Pradesh地区疟疾强化控制和非强化控制区的斯氏按蚊基因流和种群遗传结构分析

[目的]斯氏按蚊Anopheles stephensi是亚洲东南部城市人体疟疾的主要媒介,印度12％的疟疾病例由其引起.本实验研究了印度中部Madhya Pradesh地区东北部的疟疾强化控制(EMCP)区和非强化控制(非EMCP)区斯氏按蚊的基因流.在EMCP区,由于采用了各种疟疾防控措施因而疟疾病例首先降低,但是很快回升,说明总的疟疾风险维持稳定.[方法]应用7个微卫星位点,对印度中部Madhya Pradesh地区东北部的4个EMCP区和非EMCP区采集的斯氏按蚊进行基因分型,以分析各种群参数.[结果]发现各标记在所有种群中表现出高度的多态性.在两区间未发现很大的遗传多样性.观察到EMCP区的东部种群(FST=0.0485,RST =0.1112)比非EMCP区的北部种群(FST=0.020,RST =0.0145)具有较高的遗传分化,在EMCP区和非EMCP区之间观察到较高的基因流(12.90,6.16,5.06和2.38).RST的灵敏度高于FST,说明分化可能是由于突变而非遗传漂变引起的.[结论]本研究表明,在EMCP区和非EMCP区内以及EMCP区和非EMCP区之间存在很高的基因流.基因流水平高以及抗虫性的发展似乎是EMCP区和非EMCP区疟疾病例发生增加的重要原因.     

Hyperoxia-induced apoptosis and Fas/FasL expression in lung epithelial cells

Alveolar epithelial apoptosis is an important feature of hyperoxia-induced lung injury in vivo and has been described in the early stages of bronchopulmonary dysplasia (chronic lung disease of preterm newborn). Molecular regulation of hyperoxia-induced alveolar epithelial cell death remains incompletely understood. In view of functional involvement of Fas/FasL system in physiological postcanalicular type II cell apoptosis, we speculated this system may also be a critical regulator of hyperoxia-induced apoptosis. The aim of this study was to investigate the effects of hyperoxia on apoptosis and apoptotic gene expression in alveolar epithelial cells. Apoptosis was studied by TUNEL, electron microscopy, DNA size analysis, and caspase assays. Fas/FasL expression was determined by Western blot analysis and RPA. We determined that in MLE-12 cells exposed to hyperoxia, caspase-mediated apoptosis was the first morphologically and biochemically recognizable mode of cell death, followed by necrosis of residual adherent cells. The apoptotic stage was associated with a threefold upregulation of Fas mRNA and protein expression and increased susceptibility to direct Fas receptor activation, concomitant with a threefold increase of FasL protein levels. Fas gene silencing by siRNAs significantly reduced hyperoxia-induced apoptosis. In murine fetal type II cells, hyperoxia similarly induced markedly increased Fas/FasL protein expression, confirming validity of results obtained in transformed MLE-12 cells. Our findings implicate the Fas/FasL system as an important regulator of hyperoxia-induced type II cell apoptosis. Elucidation of regulation of hyperoxia-induced lung apoptosis may lead to alternative therapeutic strategies for perinatal or adult pulmonary diseases characterized by dysregulated type II cell apoptosis.     

Differential effects of hydroxyurea and zileuton on interleukin-13 secretion by activated murine spleen cells: implication on the expression of vascular cell adhesion molecule-1 and vasoocclusion in sickle cell anemia

BACKGROUND: Interleukin-13 (IL-13), a TH2 cytokine, upregulates the expression of vascular cell adhesion molecule-1 on endothelial cells, a factor involved in vasoocclusion in sickle cell disease (SCD). Hydroxyurea improves clinical status of SCD patients in part by induction of fetal hemoglobin. Its effect on IL-13 secretion has not been investigated. OBJECTIVE: To determine whether hydroxyurea and zileuton, a hydroxyurea derivative with antiinflammatory properties, affect IL-13 secretion. METHODS: We measured IL-13 in the supernatant of murine spleen cells incubated without and with hydroxyurea, zileuton (10 microg/ml), concanavalin A (2.5 microg/ml), and anti-CD3 (50 ng/ml) (n=8). RESULTS: Hydroxyurea and zileuton do not affect baseline IL-13 secretion. Unexpectedly, hydroxyurea increases IL-13 levels above baseline (120%, 216.5%, [p<0.05] after 24 h and 48 h, respectively) in lymphocytes activated by anti-CD3, while zileuton reduces them by 59%-78% (p<0.005). In lymphocytes activated by concanavalin A, hydroxyurea and zileuton reduce IL-13 secretion by 24-36% and 50-87%, respectively (p<0.05). Hydroxyurea, but not zileuton, significantly inhibits spleen cell proliferative responses to mitogens (p<0.005). CONCLUSION: Data suggest that hydroxyurea up-regulates IL-13 secretion in anti-CD3-activated lymphocytes through gene activation but not by altered cell proliferation. Increased IL-13 secretion may contribute to unresponsiveness of certain SCD patients to hydroxyurea. The potential benefit of zileuton in the management of vasoocclusion is discussed.