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101.
In this paper, the electrochemical behavior of myricetin on a gold nanoparticle/ethylenediamine/multi-walled carbon-nanotube modified glassy carbon electrode (AuNPs/en/MWCNTs/GCE) has been investigated. Myricetin effectively accumulated on the AuNPs/en/MWCNTs/GCE and caused a pair of irreversible redox peaks at around 0.408 V and 0.191 V (vs. Ag/AgCl) in 0.1 mol L−1 phosphate buffer solution (pH 3.5) for oxidation and reduction reactions respectively. The heights of the redox peaks were significantly higher on AuNPs/en/MWNTs/GCE compare with MWCNTs/GC and there was no peak on bare GC. The electron-transfer reaction for myricetin on the surface of electrochemical sensor was controlled by adsorption. Some parameters including pH, accumulation potential, accumulation time and scan rate have been optimized. Under the optimum conditions, anodic peak current was proportional to myricetin concentration in the dynamic range of 5.0×10−8 to 4.0×10−5 mol L−1 with the detection limit of 1.2×10−8 mol L−1. The proposed method was successfully used for the determination of myricetin content in tea and fruit juices. 相似文献
102.
Ashkani S Rafii MY Sariah M Siti Nor Akmar A Rusli I Abdul Rahim H Latif MA 《Genetics and molecular research : GMR》2011,10(3):1345-1355
Among 120 simple sequence repeat (SSR) markers, 23 polymorphic markers were used to identify the segregation ratio in 320 individuals of an F(2) rice population derived from Pongsu Seribu 2, a resistant variety, and Mahsuri, a susceptible rice cultivar. For phenotypic study, the most virulent blast (Magnaporthe oryzae) pathotype, P7.2, was used in screening of F(2) population in order to understand the inheritance of blast resistance as well as linkage with SSR markers. Only 11 markers showed a good fit to the expected segregation ratio (1:2:1) for the single gene model (d.f. = 1.0, P < 0.05) in chi-square (χ(2)) analyses. In the phenotypic data analysis, the F(2) population segregated in a 3:1 (R:S) ratio for resistant and susceptible plants, respectively. Therefore, resistance to blast pathotype P7.2 in Pongsu Seribu 2 is most likely controlled by a single nuclear gene. The plants from F(2) lines that showed resistance to blast pathotype P7.2 were linked to six alleles of SSR markers, RM168 (116 bp), RM8225 (221 bp), RM1233 (175 bp), RM6836 (240 bp), RM5961 (129 bp), and RM413 (79 bp). These diagnostic markers could be used in marker assisted selection programs to develop a durable blast resistant variety. 相似文献
103.
Tengku Shahrul Anuar Hesham M. Al-Mekhlafi Mohamed Kamel Abdul Ghani Siti Nor Azreen Fatmah Md Salleh Nuraffini Ghazali Mekadina Bernadus Norhayati Moktar 《The Korean journal of parasitology》2013,51(2):231-236
The present study was conducted to investigate the clinical outcomes of Entamoeba histolytica infection in symptomatic and asymptomatic Orang Asli (aborigine) communities in Malaysia. Examination was performed on 500 stool samples obtained from Orang Asli communities in 3 different states using formalin-ether concentration, trichrome staining, and single-round PCR techniques. Out of 500 stool samples, single infection of E. histolytica, Entamoeba dispar, and Entamoeba moshkovskii was identified in 3.2%, 13.4%, and 1%, respectively. In addition, 10 samples had mixed infections with E. histolytica and E. dispar. Six samples containing E. dispar were also positive for E. moshkovskii, and only 2 samples had E. histolytica in association with E. dispar and E. moshkovskii. Seventeen E. histolytica-positive samples were from symptomatic subjects, whereas the remaining 11 samples came from asymptomatic subjects. These findings suggest a predominant distribution of pathogenic potential of E. histolytica strains in this community. Therefore, further studies on genotyping of E. histolytica is required, to find out association between E. histolytica genotype and the outcome of the infection. 相似文献
104.
Hossein Kamaladini Siti Nor Akmar Abdullah Maheran Abdul Aziz Ismanizan Bin Ismail Fatemeh Haddadi 《Journal of plant physiology》2013
Metallothioneins (MTs) are cysteine-rich metal-binding proteins that are involved in cell growth regulation, transportation of metal ions and detoxification of heavy metals. A mesocarp-specific metallothionein-like gene (MT3-A) promoter was isolated from the oil palm (Elaeis guineensis Jacq). A vector construct containing the MT3-A promoter fused to the β-glucuronidase (GUS) gene in the pCAMBIA 1304 vector was produced and used in Agrobacterium-mediated transformation of tomato. Histochemical GUS assay of different tissues of transgenic tomato showed that the MT3-A promoter only drove GUS expression in the reproductive tissues and organs, including the anther, fruit and seed coat. Competitive RT-PCR and GUS fluorometric assay showed changes in the level of GUS mRNA and enzyme activity in the transgenic tomato (T0). No GUS mRNA was found in roots and leaves of transgenic tomato. In contrast, the leaves of transgenic tomato seedlings (T1) produced the highest GUS activity when treated with 150 μM Cu2+ compared to the control (without Cu2+). However, Zn2+ and Fe2+ treatments did not show GUS expression in the leaves of the transgenic tomato seedlings. Interestingly, the results showed a breaking-off tissue-specific activity of the oil palm MT3-A promoter in T1 seedlings of tomato when subjected to Cu2+ ions. 相似文献
105.
Although hemodialysis treatment has greatly increased the life expectancy of end stage renal disease patients, low quality of life among hemodialysis patients is frequently reported. This cross-sectional study aimed to determine the relationship between medical history, hemodialysis treatment and nutritional status with the mental and physical components of quality of life in hemodialysis patients. Respondents (n=90) were recruited from Hospital Kuala Lumpur and dialysis centres of the National Kidney Foundation of Malaysia. Data obtained included socio-demography, medical history, hemodialysis treatment and nutritional status. Mental and physical quality of life were measured using the Mental Composite Summary (MCS) and Physical Composite Summary (PCS) of the Short-Form Health Survey 36-items, a generic core of the Kidney Disease Quality of Life Short Form. Two summary measures and total SF-36 was scored as 0–100, with a higher score indicating better quality of life. Approximately 26 (30%) of respondents achieved the body mass index (24 kg/m2) and more than 80% (n=77) achieved serum albumin level (>35.0 mg/dL) recommended for hemodialysis patients. The majority of respondents did not meet the energy (n=72, 80%) and protein (n=68,75%) recommendations. The total score of SF-36 was 54.1±19.2, while the score for the mental and physical components were 45.0±8.6 and 39.6±8.6, respectively. Factors associated with a higher MCS score were absence of diabetes mellitus (p=0.000) and lower serum calcium (p=0.004), while higher blood flow (p=0.000), higher serum creatinine (p=0.000) and lower protein intake (p=0.006) were associated with a higher PCS score. To improve the overall quality of life of hemodialysis patients, a multidisciplinary intervention that includes medical, dietetic and psychosocial strategies that address factors associated with mental and physical quality of life are warranted to reduce further health complications and to improve quality of life. 相似文献
106.
Ismail NF Hamdan S Mahadi NM Murad AM Rabu A Bakar FD Klappa P Illias RM 《Biotechnology letters》2011,33(5):999-1005
l-Asparaginase II signal peptide was used for the secretion of recombinant cyclodextrin glucanotransferase (CGTase) into the
periplasmic space of E. coli. Despite its predominant localisation in the periplasm, CGTase activity was also detected in the extracellular medium, followed
by cell lysis. Five mutant signal peptides were constructed to improve the periplasmic levels of CGTase. N1R3 is a mutated
signal peptide with the number of positively charged amino acid residues in the n-region increased to a net charge of +5. This mutant peptide produced a 1.7-fold enhancement of CGTase activity in the periplasm
and significantly decreased cell lysis to 7.8% of the wild-type level. The formation of intracellular inclusion bodies was
also reduced when this mutated signal peptide was used as judged by SDS–PAGE. Therefore, these results provide evidence of
a cost-effective means of expression of recombinant proteins in E. coli. 相似文献
107.
The annually reoccurring blooms that characterize the surface waters of the Baltic Sea are dominated by filamentous, heterocystous cyanobacteria such as Nodularia spumigena. In a previous study, we have demonstrated that N. spumigena strain AV1 differentiates heterocysts in the absence of detectable nitrogen fixation activity, an unusual physiological trait that is clearly distinct from other well-studied cyanobacteria. To further analyze the uncoupling between these two processes, we analyzed the gene expression and modification of the nitrogenase enzyme (the enzyme responsible for nitrogen fixation) in N. spumigena AV1, as well as in several other N. spumigena strains. Here, we demonstrate the occurrence of two nifH gene copies in N. spumigena strain AV1, only one of which is located in a complete nifHDK cluster and several NifH protein forms. Furthermore, we demonstrate the occurrence of a DNA rearrangement mechanism acting within the nifH gene copy located in the nifHDK cluster and present only in the strains exhibiting the previously reported uncoupling between heterocyst differentiation and nitrogen fixation processes. These data stress the existence of a distinct and complex regulatory circuit related to nitrogen fixation in this ecologically significant bloom-forming cyanobacterium. 相似文献
108.
109.
Sumiko Minobe Shingo Fukui Rumiko Saiki Tadashi Kajita Suchitra Changtragoon Nor Aini Ab Shukor A. Latiff B. R. Ramesh Osamu Koizumi Tsuneyuki Yamazaki 《Conservation Genetics》2010,11(1):301-310
To evaluate the genetic diversity of a mangrove species and clarify the genetic structure of its populations, we studied nucleotide
polymorphism in two DNA regions of Bruguiera gymnorhiza collected from the southern islands of Japan, Thailand, Malaysia, Indonesia, Micronesia, and India. The two DNA sequences
were the chloroplast (cp) intergenic spacer between trnL and trnF genes (ca. 300 bp), and a part (ca. 550 bp) of the nuclear gene coding for glyceraldehyde-3-phosphate dehydrogenase (GapCp). Little polymorphism was found within each of the three geographical regions, Pacific Ocean, Bay of Bengal and Arabian Sea.
Throughout the vast regions east of the Malay peninsula including Indonesia, Thailand, Micronesia and the southern islands
of Japan (Pacific Ocean), essentially only one haplotype (apart from variation in number of a T repeat) was present. A second
haplotype was present on the western coast of Malay Peninsula and the eastern coast of India (Bay of Bengal). On the southwest
of Malay Peninsula both of these haplotypes were present. Finally a third haplotype was found only on the western coast of
India (Arabian Sea). When taken over all geographic populations, total nucleotide variation within the species was large (μ = 0.006, average of the two genes). Our results are consistent with the hypothesis that this low genetic diversity within
any local population and differentiation between the different oceans or regions are caused by very low gene flow between
each of the different oceans coupled with frequent fluctuation of population sizes due to the change in sea level. The significance
of these results is discussed from evolutionary point of the mangrove forests. 相似文献
110.
Zakaria ZA Raden Mohd Nor RN Hanan Kumar G Abdul Ghani ZD Sulaiman MR Rathna Devi G Mat Jais AM Somchit MN Fatimah CA 《Canadian journal of physiology and pharmacology》2006,84(12):1291-1299
The present study was carried out to establish the antinociceptive, anti-inflammatory, and antipyretic properties of the aqueous extract of Melastoma malabathricum leaves in experimental animals. The antinociceptive activity was measured using abdominal constriction, hot-plate, and formalin tests, whereas the anti-inflammatory and antipyretic activities were measured using carrageenan-induced paw edema and brewer's yeast-induced pyrexia tests, respectively. The extract, which was obtained after soaking the air-dried leaves in distilled water for 72 h and then preparing in concentrations of 10%, 50%, and 100% (v/v), was administered subcutaneously 30 min prior to subjection to the above mentioned assays. At all concentrations tested, the extract was found to exhibit significant (P < 0.05) antinociceptive, anti-inflammatory, and antipyretic activities in a concentration-independent manner. Our findings that the aqueous extract of M. malabathricum possesses antinociceptive, anti-inflammatory, and antipyretic activities supports previous claims on its traditional uses to treat various ailments. 相似文献