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41.
Madiha Kanwal Saadia Alyas Muhammad Afzal Atika Mansoor Rashda Abbasi Flora Tassone Sajid Malik Kehkashan Mazhar 《PloS one》2015,10(4)
Fragile-X syndrome (FXS) is the most common form of inherited intellectual disability (ID) and affects 0.7–3.0% of intellectually compromised population of unknown etiology worldwide. It is mostly caused by repeat expansion mutations in the FMR1 at chromosome Xq27.3. The present study aimed to develop molecular diagnostic tools for a better detection of FXS, to assess implementation of diagnostic protocols in a developing country and to estimate the prevalence of FXS in a cohort of intellectually disabled subjects from Pakistan. From a large pool of individuals with below normal IQ range, 395 subjects with intellectual disability of unknown etiology belonging to different regions of the country were recruited. Conventional-PCR, modified-PCR and Southern blot analysis methods were employed for the detection of CGG repeat polymorphisms in the FMR1 gene. Initial screening with conventional-PCR identified 13 suspected patients. Subsequent investigations through modified PCR and Southern blot analyses confirmed the presence of the FMR1 mutation, suggesting a prevalence of 3.5% and 2.8% (mean 3.3%) among the male and female ID patients, respectively. These diagnostic methods were further customized with the in-house conditions to offer robust screening of referral patients/families for diagnostics and genetic counseling. Prescreening and early diagnosis are crucial for designing a prudent strategy for the management of subjects with ID. Outcome of the study recommends health practitioners for implementation of molecular based FXS diagnosis in routine clinical practice to give a better care for patients similar to the ones included in the study. 相似文献
42.
David Rotsch Tom Brossard Saadia Bihmidine Weijiang Ying Vikram Gaddam Michael Harmata J. David Robertson Michael Swyers Silvia S. Jurisson David M. Braun 《PloS one》2015,10(5)
Sugars produced from photosynthesis in leaves are transported through the phloem tissues within veins and delivered to non-photosynthetic organs, such as roots, stems, flowers, and seeds, to support their growth and/or storage of carbohydrates. However, because the phloem is located internally within the veins, it is difficult to access and to study the dynamics of sugar transport. Radioactive tracers have been extensively used to study vascular transport in plants and have provided great insights into transport dynamics. To better study sucrose partitioning in vivo, a novel radioactive analog of sucrose was synthesized through a completely chemical synthesis route by substituting fluorine-18 (half-life 110 min) at the 6’ position to generate 6’-deoxy-6’[18F]fluorosucrose (18FS). This radiotracer was then used to compare sucrose transport between wild-type maize plants and mutant plants lacking the Sucrose transporter1 (Sut1) gene, which has been shown to function in sucrose phloem loading. Our results demonstrate that 18FS is transported in vivo, with the wild-type plants showing a greater rate of transport down the leaf blade than the sut1 mutant plants. A similar transport pattern was also observed for universally labeled [U-14C]sucrose ([U-14C]suc). Our findings support the proposed sucrose phloem loading function of the Sut1 gene in maize, and additionally demonstrate that the 18FS analog is a valuable, new tool that offers imaging advantages over [U-14C]suc for studying phloem transport in plants. 相似文献
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44.
Singh N Macnamara E Rashid S Ambati J Kontos CD Higgins E Ambati BK 《Biochemical and biophysical research communications》2005,332(1):194-199
This study was designed to determine if soluble Tie2 (sTie2) expression inhibits and regresses corneal neovascularization, and if VEGF contributes to its effect. The corneas of BALB/c mice were scraped and the mice were injected with either an adenovirus expressing soluble Tie2 (Ad.sTie2) or an empty adenoviral vector. When injected at the inhibition timepoint (one day prior to corneal injury), the mean percentage of neovascularized corneal area two weeks later in Ad.sTie2-treated mice vs. controls was 56.37+/-9.15% vs. 85.79+/-3.55% (p=0.04). At the regression timepoint (4 weeks after corneal scrape), the mean area of corneal neovascularization in Ad.sTie2-treated mice was 42.89+/-4.74% vs. 75.01+/-3.22% in the control group (p=0.007). VEGF expression was significantly higher in Ad.sTie2-treated mice at the inhibition timepoint and there was no significant difference at the regression timepoint. These findings suggest that sTie2 inhibits and regresses corneal neovascularization in a VEGF-independent manner. 相似文献
45.
Vouyiouklis DA Anderson TJ King HE Kirkham D Karim SA Johnson KJ Griffiths IR 《Genomics》2002,80(2):126-128
Hindshaker (hsh) is a novel, spontaneous, autosomal recessive mouse mutation displaying a myelin deficit, predominantly in the spinal cord. It is characterized by developmentally dependent hypomyelination, first evident at postnatal day (P) 10, followed by progressive but incomplete recovery by P42. Hypomyelination is associated with a decreased number of mature oligodendrocytes, which fail to form complete myelin sheaths. Heterozygotes are phenotypically normal, and the hsh mutation shows considerable variation in penetrance and expression depending on genetic background, indicating the influence of modifying loci. Here, we followed an outcross/backcross breeding strategy in conjunction with genotyping for microsatellites and a novel marker for the gene S100a4. We describe the genomic mapping of the hsh mutation to within a 1.2-cM region near the centromere of mouse chromosome 3. We found that hsh is flanked between D3Mit187 proximally and S100a4 distally. The area containing hsh is gene-rich, with a high proportion of the genes specific to nervous tissue. Identification of the hsh mutation will aid our understanding of processes important in regional control of oligodendrocyte development and myelination. 相似文献
46.
Saadia Berrada Francoise Lefebvre Marie-Francoise Harmand 《In vitro cellular & developmental biology. Animal》1995,31(9):698-702
This paper describes the studies of human recombinant basic fibroblast growth factor (rhFGF-2) for its effects on human osteoblast
growth and phenotype expression. During a 24-h period of treatment, rhFGF-2 highly stimulated DNA synthesis in a dose-related
fashion with a maximum stimulation of 150% for 1 ng/ml. On the other hand, rhFGF-2 decreases alkaline phosphatase activity,
synthesis of type I collagen, and cumulative amount of osteocalcin. Moreover, rhFGF-2 provoked a threefold increase in the
amount of intracellular cAMP. Scatchard plots show the presence of two classes of [125I] rhFGF-2 receptors. This data suggests that rhFGF-2 which stimulate cell replication may act indirectly as an anabolic agent
and stimulate some of the phenotypic expression markers. 相似文献
47.
Saadia Basheer Muhammad Sohail Akram Muhammad Akhtar 《Bioscience, biotechnology, and biochemistry》2019,83(3):436-445
The gene encoding copper-dependent laccase from Bacillus subtilis strain R5 was cloned and expressed in Escherichia coli. Initially the recombinant protein was produced in insoluble form as inclusion bodies. Successful attempts were made to produce the recombinant protein in soluble and active form. The laccase activity of the recombinant protein was highly dependent on the presence of copper ions in the growth medium and microaerobic conditions during protein production. The purified enzyme exhibited highest activity at 55 °C and pH 7.0. The recombinant protein was highly thermostable, albeit from a mesophilic source, with a half-life of 150 min at 80 °C. Similar to temperature, the recombinant protein was stable in the presence of organic solvents and protein denaturants such as urea. Furthermore, the recombinant protein was successfully utilized for the degradation of various synthetic dyes reflecting its potential use in treatment of wastewater in textile industry.
Abbreviations: ABTS,2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid; CBB, Coomassie brilliant blue; SGZ, syringaldazine; DMP, 2,2-dimethoxy phenol. 相似文献
48.
Raza Ashraf Naeem Rashid Saadia Basheer Iram Aziz Muhammad Akhtar 《Biochemistry. Biokhimii?a》2017,82(1):13-23
Genome search of Bacillus subtilis revealed the presence of an open reading frame annotated as glutathione-dependent formaldehyde dehydrogenase/alcohol dehydrogenase. The open reading frame consists of 1137 nucleotides corresponding to a polypeptide of 378 amino acids. To examine whether the encoded protein is glutathione-dependent formaldehyde dehydrogenase or alcohol dehydrogenase, we cloned and characterized the gene product. Enzyme activity assays revealed that the enzyme exhibits a metal ion-dependent alcohol dehydrogenase activity but no glutathione-dependent formaldehyde dehydrogenase or aldehyde dismutase activity. Although the protein is of mesophilic origin, optimal temperature for the enzyme activity is 60°C. Thermostability analysis by circular dichroism spectroscopy revealed that the protein is stable up to 60°C. Presence or absence of metal ions in the reaction mixture did not affect the enzyme activity. However, metal ions were necessary at the time of protein production and folding. There was a marked difference in the enzyme activity and CD spectra of the proteins produced in the presence and absence of metal ions. The experimental results obtained in this study demonstrate that the enzyme is a bona-fide alcohol dehydrogenase and not a glutathionedependent formaldehyde dehydrogenase. 相似文献
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Tayyiba Afzal Yamin Bibi Muhammad Ishaque Saadia Masood Abdul Qayyum Sobia Nisa Zahid Hussain Shah Hameed Alsamadany Gyuhwa Chung 《Saudi Journal of Biological Sciences》2022,29(2):1185
Medicinal plants have significant contribution in pharmaceutical industries being producers of compounds utilized as precursors for drug development. A plant of Lamiaceae family; Pseudocaryopteris foetida had not been investigated for its biomedical potential. Current research was aimed to investigate phytochemical analysis, cytotoxic potential and antioxidant activity of crude methanolic extract and fractions of Pseudocaryopteris foetida (leaves). The preliminary phytochemical analysis of crude methanolic extracts and fractions of Pseudocaryopteris foetida revealed that plant is rich in phenolic and flavonoid classes of secondary metabolites while presence of tannin was observed only in crude methanolic extract. The cytotoxicity was determined using brine shrimp lethality test. Different concentrations (25, 50, 100, 150, 200 and 250 µg/mL) of crude methanolic extract and fractions exhibited dose dependent cytotoxicity. However, The LD50 for all the extracts was more than 200 µg/mL indicating weak cytotoxic potential of Pseudocaryopteris foetida. The antioxidant capabilities of crude methanolic extract and fraction of Pseudocaryopteris foetida were analyzed by in vitro bio assays including DPPH, ABTS, Reducing power and phosphomolybdate antioxidant assays using ascorbic acid as standard. The crude methanolic extract showed IC50 (256.38 ± 0.6 and 314.95 ± 1.1 µg/mL) for DPPH and ABTS respectively, while total antioxidant capacity was calculated as 55.79 ± 0.5 µg/mL for crude methanolic extract of Pseudocaryopteris foetida while ascorbic acid indicated total antioxidant capacity of 71.89 ± 2.3 µg/mL. Study concluded that leaves of Pseudocaryopteris foetida were the rich source of antioxidant phytochemicals. Based on preliminary investigations further research should be focused to isolate bioactive phytochemicals as leading source of clinical medicines in future. 相似文献
50.
Mohamed Izikki Olaf Mercier Florence Lecerf Lauriane Lubert Guin Eric Hoang Peter Dorfmüller Frédéric Perros Marc Humbert Gerald Simonneau Philippe Dartevelle Elie Fadel Saadia Eddahibi 《PloS one》2013,8(10)