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Advances in Bioscience and Biotechnology 2011年第3期2卷 149-156页

作者： Hafiz Muhammad Nasir Iqbal ishtiaq Ahmed Muhammad Anjum Zia Muhammad Irfan 不详

This paper reports the purification and characterization of kinetic parameters of cellulase produced from Trichoderma viride under still culture solid state fermentation technique using cheap and an easily available agricultural waste material, wheat straw as growth supported substrate. Trichoderma viride was cultured in fermentation medium of wheat straw under some previously optimized growth conditions and maximum activity of 398±2.43U/mL obtained after stipulated fermentation time period. Cellulase was purified 2.33 fold with specific activity of 105U/mg in comparison to crude enzyme extract using ammonium sulfate precipitation, dialysis and Sephadex-G-100 column chromatography. The enzyme was shown to have a relative low molecular weight of 58kDa by sodium dodecyl sulphate poly-acrylamide gel electrophoresis. The purified enzyme displayed 6.5 and 55oC as an optimum pH and temperature respectively. Using carboxymethyl cellulose as substrate, the enzyme showed maximum activity (Vmax) of 148U/mL with its corresponding KM value of 68μM. Among activators/inhibitors SDS, EDTA, and Hg2+ showed inhibitory effect on purified cellulase whereas, the enzyme activated by Co2+ and Mn2+ at a concentration of 1mM. The purified cellulase was compatible with four local detergent brands with up to 20 days of shelf life at room temperature suggesting its potential as a detergent additive for improved washing therefore, it is concluded that it may be potentially useful for industrial purposes especially for detergent and laundry industry.

关键词： Cellulase Trichoderma viride Purification SDS-PAGE Characterization Detergent Compatibility

A challenging case of alpha-fetoprotein-result discrepancies in a patient with chronic hepatitis B

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Gastroenterology Report 2020年第6期8卷 484-486,I0003页

作者： Pir A.Shah Allison Onken Rizwan ishtiaq Muhammad H.Maqsood Shyam S.Patel Karen J.Campoverde Reyes Adrianna Z.Herskovits Daryl T.Y.Lau Department of Medicine Liver CenterDivision of GastroenterologyBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Department of Pathology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA

Introduction Alpha-fetoprotein(AFP)is the most abundant serum protein found in the human fetus,produced by the yolk sac and the liver[1].The levels of maternal serum AFP reach a peak value at28-32 weeks of gestation and decrease rapidly after birth and usually drop to the normal at 8-12 months of *** normal serum AFP level for an adult is<20 ng/mL[2].In contrast,livertumor cells usually synthesize and secrete an increased level of *** ultrasound and AFP are generally recommended as the screening modality for HCC for patients at risk for development of hepatocellular carcinoma(HCC)[1].AFP-L3,an isoform of AFP that binds Lens culinaris agglutinin,can be particularly useful in the early identification of aggressive HCC[2].These assays,however,can generate false-positive and false-negative AFP *** patients with advanced HCC,20%had normal AFP levels,whereas some patients with liver diseases had significant AFP elevation without liver cancer in long-term surveillance[3].Elevated AFP levels could be associated with active liver diseases with hepatocyte regeneration[4,5].In that setting,the AFP level will decline with improvement of the underlying liver *** case illustrated the dilemma and uncertainties as a result of persistent abnormal AFP values after extensive clinical investigations.

关键词：甲胎蛋白 fetus false

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水生生物学报 2011年第5期35卷 727-738页

作者： Abu Shufian ishtiaq Ahmed 于力群朱作言孙永华中国科学院水生生物研究所淡水生态与生物技术国家重点实验室武汉430072

GHR信号通路在动物出生后的生长中扮演着重要角色。实验利用斑马鱼模型研究了GHR信号相关基因在成体组织、胚胎发育以及幼体期的表达情况,这些基因包括gh、ghra、ghrb、jak2a、jak2b、stat5.1、stat5.2、igf1、c-fos、socs1和socs2。值... 详细信息

GHR信号通路在动物出生后的生长中扮演着重要角色。实验利用斑马鱼模型研究了GHR信号相关基因在成体组织、胚胎发育以及幼体期的表达情况,这些基因包括gh、ghra、ghrb、jak2a、jak2b、stat5.1、stat5.2、igf1、c-fos、socs1和socs2。值得关注的是,上述的大部分基因都存在母源性表达,且它们的合子表达均起始在体节早期之前。这说明在有功能性的脑垂体形成之前和完善的循环系统建立之前,GH及GH信号相关因子就已经存在于早期胚胎中,因此GH很可能是控制胚胎发育的一系列自分泌/旁分泌生长因子中的一员。同时,我们发现成体组织的socs表达水平与GH信号靶基因igf1和c-fos的表达呈某种程度的负相关。我们利用实时定量PCR技术和荧光素酶分析技术,通过注射GH和GHR表达载体,在斑马鱼胚胎中分析了它们促进GH信号靶基因c-fos和igf1转录活性以及GH应激启动子spi2.1活性的能力。由此,研究利用斑马鱼胚胎建立一个体内研究模型来评估发育过程中的GH信号激活(GHSA)。在受精后1天(dpf)和3dpf斑马鱼胚胎中,单独过表达gh或ghr均可以显著刺激GHSA,这表明在1dpf的斑马鱼胚胎中即存在功能性的GH和GHR蛋白表达,而这一时期是在功能性垂体的形成之前的。gh以及ghr的协同过表达则可以显著放大gh或ghr单独过表达的GHSA效果。

关键词：生长激素生长激素受体 GHR信号通路斑马鱼转录分析

Plant Growth Promoting Rhizobacteria Having 1-Aminocyclopropane-1-Carboxylic Acid Deaminase to Induce Salt Tolerance in Sunflower (<i>Helianthus annus L.</i>)

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Natural Resources 2015年第6期6卷 391-397页

作者： Muhammad Zahid Kiani Arshad Ali Tariq Sultan Rizwan Ahmad Syed ishtiaq Hydar PARC Institute of Advanced Studies in Agriculture Islamabad Pakistan Land Resources Research Institute National Agricultural Research Center Islamabad Pakistan

Soil salinity badly affects agriculture productivity through accumulation of salts in upper layers of soils. The harmful effects of salts in arable lands have influenced modern as well as ancient civilizations. A pot study was carried out to test the performance of two PGPR isolates (KS 8, KS 28) on sunflower (SMH-0917) under different salinity levels (8, 10 and 12 dS·m-1). These salinity levels were developed by adding calculated amount of salts (NaCl, Na2SO4, CaCl2 and MgSO4) with ratio of 3:4:2:1. The bacterial strains KS 8 and KS 28 were applied separately in two treatments while third treatment was co-inoculation (KS mix). Completely randomized experimental design (CRD) was used and data were collected at flowering stage about pre-decided plant growth parameters (plant height, shoot dry weight and root dry weight). The bacterial isolate KS 8 showed an increase of 26, 102% and 83% in plant height, shoot dry weight and root dry weight at EC 8 dS·m-1, while this improvement was 67%, 163% and 296% at EC 10 dS·m-1, however an increase of 100%, 74% and 382% was recorded over control respectively at EC 12 dS·m-1. Similarly isolate KS 28 exhibited an increase of 14%, 69% and 54% in plant height;shoot dry weight and root dry weight at EC 8 dS·m-1, whereas this improvement was 56%, 163% and 188% at EC 10 dS·m-1, while an increase of 60%, 41% and 282% was registered respectively over control at EC 12 dS·m-1. The increase due to mixture treatments was 4%, 41% and 16% in plant height, shoot dry weight and root dry weight at EC 8 dS·m-1, while an increase of 33%, 57% and 100% at EC 10 dS·m-1, whereas an improvement of 53%, 33% and 164% respectively was noted at EC 12 dS·m-1 over un-inoculated. The isolate KS 8 performed better than KS 28 and mixture treatment. These two PGPR strains could be used to mitigate the adverse impact caused by salinity stress on sunflower.

关键词： Plant Growth Promoting Rhizobacteria Strains 1-Aminocyclopropane-1-Carboxylic Acid (ACC) Deaminase Salinity

Structural Interpretation and Petrophysical Analysis for Reservoir Sand of Lower Goru, Miano Area, Central Indus Basin, Pakistan

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International Journal of Geosciences 2017年第4期8卷 379-392页

作者： Muhammad Sohail Khan Farhana Masood Qadeer Ahmed ishtiaq Ahmed Khan Jadoon Naveed Akram School of Earth and Space Sciences University of Science and Technology of China Hefei China Quaid-i-Azam University Islamabad Pakistan Oil and Gas Development Company Limited Islamabad Pakistan COMSATS Institute of Information Technology Abbottabad Pakistan

The main purpose of this research is to estimate the structural analysis and hydrocarbon potential of Miano Block by using seismic and well log techniques. Miano area hosts a number of gas fields with structural and stratigraphic traps. The area is located in Central Indus Basin which is a part of an extensional regime exhibiting normal faulting due to the split of the Indian Plate firstly from Africa and then from Madagascar and Seychelles. Miano area recognized as a proven petroleum province which has complex tectonic history of Cretaceous extensional and overprints of Tertiary strike-slip tectonics. The area has prospect with accumulation of hydrocarbons in structural and stratigraphic traps including pinchouts. NW-SE oriented Khairpur and Mari Highs are main structural features with impact on the fault system. The sands of Lower Goru of Lower Cretaceous age are acting as a reservoir in the area. The area has great potential of hydrocarbons for which more exploratory wells are required to be drilled with better insight of structural and stratigraphic traps.

关键词： Seismic Interpretation Time-and-Depth Contour Map 3D View Synthetic Seismograph Reservoir Estimation

WIMAX Implementation of Smart Grid Wide Area Power System Load Protection Model in MATLAB/SIMULINK

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Smart Grid and Renewable Energy 2012年第4期3卷 282-293页

作者： Asadullah Khan Muhammad Ali ishtiaq Ahmad Amjad Ullah Haseeb Ur Rahman Hafeez Ur Rahman Electrical Engineering Department COMSATS Institute of Information Technology Abbottabad Pakistan Electrical Engineering Department Ghanhara University Peshawar Pakistan. Electrical Engineering Department NWFP University of Engineering & Technology Peshawar Pakistan

As the revolutionary change in electric power industry begins with the latest communication infrastructure, it is on the verge of a revolutionary transformation to develop a smart grid to meet the requirements of our digital society. Wide Area Power System is made up of plentiful automated transmission and distribution systems with strong communication infrastructure, all operating in a coordinated, proficient and reliable mode. This paper is fretful with the wide area power system load protection scheme and ensuing design requirement that enhances stability as well as control. It discusses the architecture that upgrades the existing scheme by controlling all the control signals traffic between generating units, server, connected loads, and protection devices using WIMAX. The main theme of the paper is on the use of information technology to obtain more flexibility and smartness in the Wide Area Power System Load Protection by designing the Communication channel using WIMAX. Faults detected in Local area networks and Information regarding the faults of Local Areas is communicated to Load Area Manager (LAM) which takes required control action to handle it. Finally the paper shows islanding operation through WAM for the areas that becomes intensive faulty. Results have been verified in MATLAB/ SIMULIMK.

关键词： WIMAX Wide Area Network (WAN) Wide Area Manager (WAM) Local Area Manager (LAM)

Structural Styles and Petroleum Potential of Miano Block, Central Indus Basin, Pakistan

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International Journal of Geosciences 2016年第10期7卷 1145-1155页

作者： Saif-Ur-Rehman K. Jadoon Muhammad F. Mehmood Zohaib Shafiq ishtiaq A. K. Jadoon Department of Earth Sciences COMSATS Institute of Information Technology Abbottabad Pakistan Department of Earth and Environmental Sciences Bahria University Islamabad Pakistan

The main purpose of this research article is to evaluate the structural styles and hydrocarbon potential of Miano Block using seismic and well log data. The Miano Block discovered in 1993 is located in the Central Indus Basin which is a part of an extensional regime exhibiting normal faulting, formed as a result of split of the Indian Plate firstly from Africa and then from Madagascar and Seychelles. Tectonically, the Miano Block lies on the Panno-Aqil graben between two extensive regional highs i.e. Jacobabad-Khairpur High and Mari Kandhkot High. Four migrated seismic lines were used for structural enhancement;P2092-111, P2092-113 and P2092-115 (dip lines) and P2092-110 (strike line). Time and depth contours were generated for four horizons, HabibRahi Formation, Sui Main Limestone, Ranikot Formation and Lower Goru Formation which showed the presence of horst and graben structures in the subsurface. The interpretation of horst and graben structures is based on a parallel set of NS-oriented high-angle planar normal faults with dips either towards SE or SW with majority of the faults dipping towards the SW. The faults are observed to exhibit slight disruption of strata with limited displacement to the order of about 50 m in Lower Goru Formation. Thus, horst and graben structures with NS trend in the study area are interpreted. The NS trend of these structures along with similar structural dip is inconsistent to the NW-SE orientation of regional structures i.e. Panno- Aqil graben and the Jacobabad-Kharipur and Mari-Kandhkot Highs indicating about the presence of a second minor set of faults and complexity of deformation. In this setting, Maino-02 well was drilled with the primary target as B-Sands of Lower Goru Formation belonging to Lower Cretaceous age while secondary target was A-Sands of Lower Goru belonging to the same age. The result of the petrophysical analysis supports two potential zones (zone 1 and zone 2) within the Lower Goru Formation. Potential reservoir

关键词： Extensional Regime Horst and Graben

Effect of aging on stem cells

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World Journal of Experimental Medicine 2017年第1期7卷 1-10页

作者： Abu Shufian ishtiaq Ahmed Matilda HC Sheng Samiksha Wasnik David J Baylink Kin-Hing William Lau Regenerative Medicine Unit Department of MedicineLoma Linda University School of Medicine Musculoskeletal Disease Center Jerry L.Pettis Memorial VA Medical Center

Pluripotent stem cells have the remarkable self-renewal ability and are capable of differentiating into multiple diverse cells. There is increasing evidence that the aging process can have adverse effects on stem cells. As stem cells age, their renewal ability deteriorates and their ability to differentiate into the various cell types is altered. Accordingly, it is suggested aging-induced deterioration of stem cell functions may play a key role in the pathophysiology of the various aging-associated disorders. Understanding the role of the aging process in deterioration of stem cell function is crucial, not only in understanding the pathophysiology of agingassociated disorders, but also in future development of novel effective stem cell-based therapies to treat agingassociated diseases. This review article first focuses on the basis of the various aging disease-related stem cell dysfunction. It then addresses the several concepts on the potential mechanism that causes aging-related stem cell dysfunction. It also briefly discusses the current potential therapies under development for aging-associated stem cell defects.

关键词： Aging Biological aging Cellular aging Adult stem cells Premature aging Mesenchymal stem cell Stem cell renewal Tissue regeneration

Optimizing Yield and Nutrients Content in Tomato by Vermicompost Application under Greenhouse Conditions

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Natural Resources 2015年第7期6卷 457-464页

作者： Syed ishtiaq Hyder Muhammad Farooq Tariq Sultan Arshad Ali Muhammad Ali Muhammad Zahid Kiani Shahbaz Ahmad Tausif Tabssam National Agricultural Research Centre (NARC) Islamabad Pakistan

Optimizing yield and nutrients content in crop production is the high time demand of arable farming. Vermicompost furnishes one of the most promising alternatives to costly chemical fertilizer. Therefore, a greenhouse experiment was conducted at NARC, Islamabad, to investigate the effect of different levels of vermicompost [having C/N=15/1 and 14 Plant Growth Promoting Rhizobacteria (PGPR)] on growth, yield and nutrients content in hybrid tomato (National Tunnel Tomato-04-08) under greenhouse conditions during Rabi 2015. The data revealed that different rates (0.5 t·ha-1, 1 t·ha-1, 1.5 t·ha-1 and 2 t·ha-1) of vermicompost produced varied and significant (P -1) at the application of 2.0 t vermicompost ha-1 followed by 3.226 t·ha-1 where vermicompost was applied @ 1.5 t·ha-1. N, P and K content in tomato fruit and plant increased significantly with the application of increasing levels of vermicompost. The highest content of N (3.7%), P (0.67%), K (5.17%) in tomato fruit and N (3.4%), P (0.32%), K (3.2%) in tomato plant respectively were registered with soil application of vermicompost @ 2.0 t·ha-1. This study confirms that the vermicompost has a tremendous potential of plant nutrients supply for sustainable crop production.

关键词： Vermicompost PGPR Tomato Yield Nutrients and Humic Acid

Host nucleotide polymorphism in hepatitis B virusassociated hepatocellular carcinoma

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World Journal of Hepatology 2016年第10期8卷 485-498页

作者： Shilu Mathew Hany Abdel-Hafiz Abbas Raza Kaneez Fatima ishtiaq Qadri Center of Excellence in Genomic Medicine Research King Abdul Aziz University University of Colorado Denver AMC Department of Immunobiology University of Vermont IQ-Institute of Infection and Immunity King Fahd Medical Research Center King Abdul Aziz University

Hepatocellular carcinoma(HCC) is etiologically linked with hepatitis B virus(HBV) and is the leading cause of death amongst 80% of HBV patients. Among HBV affected patients, genetic factors are also involved in modifying the risk factors of HCC. However, the genetic factors that regulate progression to HCC still remain to be determined. In this review, we discuss several single nucleotide polymorphisms(SNPs) which were reportedly associated with increased or reduced risk of HCC occurrence in patients with chronic HBV infection such as cyclooxygenase(COX)-2 expression specifically at COX-2-1195G/A in Chinese, Turkish and Egyptian populations, tumor necrosis factor α and the three most commonly studied SNPs: PAT-/+, Lys939Gln(A33512C, rs2228001) and Ala499Val(C21151T, rs2228000). In genome-wide association studies, strong associations have also been found at loci 1p36.22, 11q22.3, 6p21(rs1419881, rs3997872, rs7453920 and rs7768538), 8p12(rs2275959 and rs37821974) and 22q11.21. The genes implicated in these studies include HLA-DQB2, HLA-DQA1, TCF19, HLA-C, UBE2L3, LTL, FDX1, MICA, UBE4 B and PG. The SNPs found to be associated with the above-mentioned genes still require validation in association studies in order to be considered good prognostic candidates for HCC. Screening of these polymorphisms is very beneficial in clinical experiments to stratify the higher or lower risk for HCC and may help in designing effective and efficient HCC surveillance programs for chronic HBV-infected patients if further genetic vulnerabilities are detected.

关键词： Hepatitis B virus Hepatocellular carcinoma Subtypes Genetic polymorphism Liver cirrhosis