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101.
102.
Shaheen R Faqeih E Sunker A Morsy H Al-Sheddi T Shamseldin HE Adly N Hashem M Alkuraya FS 《American journal of human genetics》2011,89(2):745-333
Adams-Oliver syndrome (AOS) is defined by the combination of aplasia cutis congenita (ACC) and terminal transverse limb defects (TTLD). It is usually inherited as an autosomal-dominant trait, but autosomal-recessive inheritance has also been documented. In an individual with autosomal-recessive AOS, we combined autozygome analysis with exome sequencing to identify a homozygous truncating mutation in dedicator of cytokinesis 6 gene (DOCK6) which encodes an atypical guanidine exchange factor (GEF) known to activate two members of the Rho GTPase family: Cdc42 and Rac1. Another homozygous truncating mutation was identified upon targeted sequencing of DOCK6 in an unrelated individual with AOS. Consistent with the established role of Cdc42 and Rac1 in the organization of the actin cytoskeleton, we demonstrate a cellular phenotype typical of a defective actin cytoskeleton in patient cells. These findings, combined with a Dock6 expression profile that is consistent with an AOS phenotype as well as the very recent demonstration of dominant mutations of ARHGAP31 in AOS, establish Cdc42 and Rac1 as key molecules in the pathogenesis of AOS and suggest that other regulators of these Rho GTPase proteins might be good candidates in the quest to define the genetic spectrum of this genetically heterogeneous condition. 相似文献
103.
A 1.4 Kb fragment of Bacillus licheniformis ATCC 14580 encoding β-glucosidase was cloned and expressed in Escherichia coli. β-Glucosidase expressed by E. coli harboring cloned gene was located entirely in the intracellular fraction. Recombinant β-glucosidase protein was purified to homogeneity level and the molecular weight was found to be 53 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis. It gave maximum activity at 50°C and pH 6. K m and V max were 0.206 mM and 1.26 U/mg, respectively, with p-nitrophenyl-β-D-glucopyranoside, while activation energy Ea, enthalpy of activation ?H and entropy of activation ΔS were found to be 66.31 kJ/mol, 64.04 kJ/mol and 48.28 J/mol/K, respectively. The pKa1 and pKa2 of the ionizable groups of active site residues involved in Vmax were found to be 5.5 and 7.0, respectively. When the recombinant β-glucosidase protein was used as a member of consortium with endoglucanase and exoglucanase for the saccharification of wheat straw, 123% increase in saccharification was observed. 相似文献
104.
Boron is an essential plant micronutrient, but it is phytotoxic if present in excessive amounts in soil for certain plants
such as Artemisia annua L. that contains artemisinin (an important antimalarial drug) in its areal parts. Artemisinin is a sesquiterpene lactone
with an endoperoxide bridge. It is quite expensive compound because the only commercial source available is A. annua and the compound present in the plant is in very low concentration. Since A. annua is a major source of the antimalarial drug and B stress is a deadly threat to its cultivation, the present research was conducted
to determine whether the exogenous application of methyl jasmonate (MeJA) could combat the ill effects of excessive B present
in the soil. According to the results obtained, the B toxicity induced oxidative stress and reduced the stem height as well
as fresh and dry masses of the plant remarkably. The excessive amounts of soil B also lowered the net photosynthetic rate,
stomatal conductance, internal CO2 concentration and total chlorophyll content in the leaves. In contrast, the foliar application of MeJA enhanced the growth
and photosynthetic efficiency both in the stressed and non-stressed plants. The excessive B levels also increased the activities
of antioxidant enzymes, such as catalase, peroxidase and superoxide dismutase. Endogenous H2O2 and O2− levels were also high in the stressed plants. However, the MeJA application to the stressed plants reduced the amount of
lipid peroxidation and stimulated the synthesis of antioxidant enzymes, enhancing the content and yield of artemisinin as
well. Thus, it was concluded that MeJA might be utilized in mitigating the B toxicity and improving the content and yield
of artemisinin in A. annua plant. 相似文献
105.
Mohd Idrees M. Naeem Tariq Aftab M. Masroor A. Khan Moinuddin 《Acta Physiologiae Plantarum》2011,33(3):987-999
A pot experiment was conducted to find out whether the foliar spray of salicylic acid (SA) could successfully ameliorate the
adverse effects of salinity stress on periwinkle. Thirty-day-old plants were supplied with Control; 0 mM NaCl + 10−5 M SA (T1); 50 mM NaCl + 0 SA (T2); 100 mM NaCl + 0 SA (T3); 150 mM NaCl + 0 SA (T4); 50 mM NaCl + 10−5 M SA (T5); 100 mM NaCl + 10−5 M SA (T6); 150 mM NaCl + 10−5 M SA (T7). The plants were sampled 90 days after sowing to assess the effect of SA on stressed and unstressed plants. Salt stress
significantly reduced the growth attributes including plant height, leaf-area index, shoot and root fresh weights, shoot and
root dry weights. Increasing NaCl concentrations led to a gradual decrease in photosynthetic parameters and activities of
nitrate reductase and carbonic anhydrase. Ascorbic acid, total alkaloids and antioxidants enzymes superoxide dismutase, catalase
and peroxidase also declined in NaCl-treated plants. The plants, undergoing NaCl stress, exhibited a significant increase
in electrolyte leakage and proline content. Foliar application of SA (10−5 M) reduced the damaging effect of salinity on plant growth and accelerated the restoration of growth processes. It not only
improved the growth parameters but also reversed the effects of salinity. Total alkaloid content was improved by SA application
both in unstressed and stressed plants. The highest level of total alkaloid content recorded in leaves of SA-treated stressed
plants was 11.1%. Foliar spray of SA overcame the adverse effect of salinity by improving the content of vincristine (14.0%)
and vinblastine (14.6%) in plants treated with 100 M NaCl. 相似文献
106.
Regulation of the androgen receptor by SET9-mediated methylation 总被引:1,自引:0,他引:1
107.
The risk posed by the quantity of heavy metal lead present in Ca supplements is of grave concern. Some lead levels have been
measured up to the extent of regulatory limit set by the United States. Calcium supplements inevitably get contaminated with
lead as both are naturally occurring elements having the same charge density. Therefore, it is imperative to indicate the
level of this toxic metal in these supplements in order to create awareness among consumers. The calcium in the supplements
is derived from natural as well as synthetic/refined sources (chelated or non-chelated). In this study, a sophisticated analytical
technique, atomic absorption spectrometer (both with FAAS and GFAAS modes of atomization), was used for the purpose of analyzing
Pb contents in 27 commonly used Ca supplements manufactured by different national and multinational companies. The daily intake
of lead through these supplements was calculated. Only 10% of the calcium supplements analyzed met the criteria of acceptable
Pb levels (1.5 μg/daily dose) in supplements/consumer products set by the United States. It was also found that Pb intake
was highest in chelated calcium supplements whereas lowest through calcium supplements with vitamin D formulation. The Pb
concentration in calcium supplements was significantly increased (p < 0.001) according to their composition. In order to validate our results from the study conducted, IAEA-certified reference
material (animal bone, H-5) was analyzed for Pb levels. The limit of detection of the method used was 0.05 μg/g and a 95%
lead recovery of IAEA-certified reference material (animal bone, H-5). 相似文献
108.
Asma Haque Tayyaba Shaheen Tahsin Gulzar Mahmood ur Rahman Fatima Jalal Summera Sattar Beenish Ehsan Zafar Iqbal Muhammad Younas 《Bioinformation》2014,10(6):371-377
Wheat is a vital dietary component for human health and widely consumed in the world. Wheat rusts are dangerous pathogens
and contribute serious threat to its production. In present study, PCR-Based DNA Markers were employed to check the rust
resistance genes among 20 wheat genotypes and 22 markers were amplified. NTSYS-pc 2.2 was used to calculate genetic diversity
and Nei and Li''s coefficients ranged from 0.55 to 0.95. Cluster analysis was obtained using UPGMA (Unweighted Pair Group
Method of Arithmetic Average) algorithm. Maximum no. of genes (23) was amplified from TW-760010 genotype whereas
minimum no of genes (14) were amplified from TW-76005 genotype. The data gained from present study open up new ways to
produce new varieties by breeding rust resistant germplasm to avoid the economic and food loss and varieties with improved
characteristics. 相似文献
109.
Sabira Begum Anjum Ayub Syeda Qamar Zehra Bina Shaheen Siddiqui M. Iqbal Choudhary Samreen 《化学与生物多样性》2014,11(5):709-718
Two new natural triterpenes, lantaninilic acid and lantoic acid, along with the known triterpenes lantadene A, and oleanolic, ursolic, betulinic, lantanolic, and camaric acid, were obtained from the aerial parts of Lantana camara through bioassay‐guided isolation, monitoring the in vitro antileishmanial activity against promastigotes of Leishmania major. Oleanolic acid ( 3 ), ursolic acid ( 4 ), lantadene A ( 5 ), and lantanilic acid ( 7 ) showed significant leishmanicidal activities with IC50 values of 53.0, 12.4, 20.4, and 21.3 μM , respectively. The IC50 value of ursolic acid ( 4 ; 12.4 μM ) was found to be comparable with that of the standard drugs, pentamidine (IC50 15.0 μM ) and amphotericin B (IC50 0.31 μM ). The in vitro activities of L. camara and its constituents against promastigotes of Leishmania major are reported here for the first time. 相似文献
110.
Poly(o-anisidine) molybdophosphate was expediently obtained by sol-gel mixing of Poly(o-anisidine) into the inorganic matrices of molybdophosphate, which was allowed to react with silver nitrate to the formation of poly(o-anisidine) molybdophosphate embedded silver nano composite. The composite was characterized by Fourier Transform Infrared Spectroscopy, X-ray powder diffraction, UV-Vis Spectrophotometry, Fluorescence Spectroscopy, Scanning Electron Microscopy/Energy-dispersive X-ray Spectroscopy and Thermogravimertic Analysis. Ion exchange capacity and distribution studies were carried out to understand the ion-exchange capabilities of the nano composite. On the basis of highest distribution studies, this nano composite cation exchanger was used as preparation of heavy metal ion selective membrane. Membrane was characterized for its performance as porosity and swelling later on was used for the preparation of membrane electrode for Hg(II), having better linear range, wide working pH range (2–4.5) with fast response in the real environment. 相似文献