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41.
Md Ruhul Amin Mohsen Ara Sharmin Md Ramiz Uddin Miah Abdul Mannan Akanda Sang Jae Suh Yong Jung Kwon Ohseok Kwon 《Entomological Research》2020,50(6):257-266
The population abundance, infestation, and harmful effects of the aphid Aphis craccivora Koch (Hemiptera: Aphididae) were studied on four bean plant species, namely the country bean (Lablab purpureus var. BARI Seem 1), the yard‐long bean (Vigna sesquipedalis var. BARI Borboti 1), the hyacinth bean (Dolichos lablab var. BARI Seem 6), and the bush bean (Phaseolus vulgaris var. BARI Jar Seem 3). Aphid abundance and infestation on the leaves, inflorescences, flowers, and pods differed significantly among the bean plant species, with P. vulgaris and V. sesquipedalis having the lowest and highest results, respectively. Aphid severity grade and the number of trichomes of the bean plant species were negatively correlated. The duration of the growth stages among the bean plant species were significantly different, with V. sesquipedalis having the shortest durations. Aphid abundance and infestation significantly affected the physical and phytochemical characteristics of the bean plant species. The highest reduction of number of leaves, flower inflorescences, and pod inflorescences per plant, and moisture and chlorophyll content in the leaves was found in L. purpureus. The results for V. sesquipedalis revealed the highest reduction in plant height, seed weight, and pH, while those of D. lablab showed the highest reduction in leaf area. 相似文献
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Kornelia Neveling Lilian?A. Martinez-Carrera Irmgard H?lker Angelien Heister Aad Verrips Seyyed?Mohsen Hosseini-Barkooie Christian Gilissen Sascha Vermeer Maartje Pennings Rowdy Meijer Margot te?Riele Catharina?J.M. Frijns Oksana Suchowersky Linda MacLaren Sabine Rudnik-Sch?neborn Richard?J. Sinke Klaus Zerres R.?Brian Lowry Henny?H. Lemmink Lutz Garbes Joris?A. Veltman Helenius?J. Schelhaas Hans Scheffer Brunhilde Wirth 《American journal of human genetics》2013,92(6):946-954
Spinal muscular atrophy (SMA) is a heterogeneous group of neuromuscular disorders caused by degeneration of lower motor neurons. Although functional loss of SMN1 is associated with autosomal-recessive childhood SMA, the genetic cause for most families affected by dominantly inherited SMA is unknown. Here, we identified pathogenic variants in bicaudal D homolog 2 (Drosophila) (BICD2) in three families afflicted with autosomal-dominant SMA. Affected individuals displayed congenital slowly progressive muscle weakness mainly of the lower limbs and congenital contractures. In a large Dutch family, linkage analysis identified a 9q22.3 locus in which exome sequencing uncovered c.320C>T (p.Ser107Leu) in BICD2. Sequencing of 23 additional families affected by dominant SMA led to the identification of pathogenic variants in one family from Canada (c.2108C>T [p.Thr703Met]) and one from the Netherlands (c.563A>C [p.Asn188Thr]). BICD2 is a golgin and motor-adaptor protein involved in Golgi dynamics and vesicular and mRNA transport. Transient transfection of HeLa cells with all three mutant BICD2 cDNAs caused massive Golgi fragmentation. This observation was even more prominent in primary fibroblasts from an individual harboring c.2108C>T (p.Thr703Met) (affecting the C-terminal coiled-coil domain) and slightly less evident in individuals with c.563A>C (p.Asn188Thr) (affecting the N-terminal coiled-coil domain). Furthermore, BICD2 levels were reduced in affected individuals and trapped within the fragmented Golgi. Previous studies have shown that Drosophila mutant BicD causes reduced larvae locomotion by impaired clathrin-mediated synaptic endocytosis in neuromuscular junctions. These data emphasize the relevance of BICD2 in synaptic-vesicle recycling and support the conclusion that BICD2 mutations cause congenital slowly progressive dominant SMA. 相似文献
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Response surface methodology (RSM) was used to evaluate the effects of fermentation parameters for cellulase production by Trichoderma reesei QM9414 and T. reesei MCG77 in solid-state fermentation using rice bran as substrate. Initial pH, moisture content and temperature were optimized using filter paper activity (FPA) as response. Statistical analysis of the results for T. reesei QM9414 showed that only moisture content had significant effect on cellulase activity and had a linear effect on enzyme activity (maximum enzyme activities were obtained at 70% moisture content). The results for T. reesei MCG77 showed that temperature and moisture content were the most significant parameters for cellulase activity. The optimum cellulase production was in the temperature range of 25-30 degrees C and moisture content between 55% and 70%. After the optimization, the FPA in T. reesei MCG77 was increased by 2.5 folds compared to that of T. reesei QM9414. 相似文献
46.
Ammari M Jeljeli M Jeljeli M Maaroufi K Roy V Sakly M Abdelmelek H 《Electromagnetic biology and medicine》2008,27(2):185-196
The present work investigated the behavioral effects of a moderate exposure (1 h per day for 5 consecutive days) to a static magnetic field (SMF, 128 mT) in male rats. SMF effects were evaluated in two sets of control and SMF-exposed rats. One set of animals was used for evaluation of SMF potential effects on emotional behaviors in the elevated plus maze and in the open field. The other set of animals was tested for learning and memory abilities in different procedures of the Morris water maze task. We found no significant difference between control and SMF-exposed rats in anxiety tests. However, the ratio of open arms time in the plus maze was reduced by half in SMF-exposed rats. In the Morris water maze, SMF-exposed rats were partially impaired during the initial learning task as well as in the retention task at one week. We conclude that static magnetic field exposure altered emotional behaviors in the plus maze and led to cognitive impairments, or at least to substantial attention disorders, in the Morris water maze. 相似文献
47.
Behnaz Forouhar Kalkhoran Farida Behzadian Farzaneh Sabahi Mohsen Karimi Hesam Mirshahabi 《Reports of Biochemistry & Molecular Biology》2013,2(1):28-34
Background:
Hepatitis delta virus (HDV) is a subviral human pathogen that exploits host RNA editing activity to produce two essential forms of the sole viral protein, hepatitis delta antigen (HDAg). Editing at the amber/W site of HDV antigenomic RNA leads to the production of the large form (L-HDAg), which is required for RNA packaging.Methods:
In this study, PCR-based site-directed mutagenesis by the overlap extension method was used to create the point mutation converting the small-HDAg (S-HDAg) stop codon to a tryptophan codon through three stages.Results:
Sequencing confirmed the desirable mutation and integrity of the L-HDAg open reading frame. The amplicon was ligated into pcDNA3.1 and transfected to Huh7 and HEK 293 cell lines. Western blot analysis using enhanced chemiluminescence confirmed L-HDAg expression. The recombinant L-HDAg localized within the nuclei of cells as determined by immunofluorescence and confocal microscopy.Conclusion:
Because L-HDAg requires extensive post-translational modifications, the recombinant protein expressed in a mammalian system might be fully functional and applicable as a tool in HDV molecular studies, as well as in future vaccine research.Key Words: Hepatitis Delta Virus, L-HDAg, SOEing-PCR 相似文献48.
Farah Idali Jan Wahlstr?m Benita Dahlberg Mohsen Khademi Tomas Olsson Anders Eklund Johan Grunewald 《Respiratory research》2009,10(1):42
Background
Activated T helper (Th)-1 pulmonary CD4+ cells and their mediators are essential for the inflammation and granulomatous process in sarcoidosis. Recently, T-cell immunoglobulin and mucin domain (TIM) molecules were suggested to be important regulators of immune function. In this study, we wanted to investigate whether TIM molecules could play a role in sarcoidosis.Methods
We used real-time polymerase chain reaction to investigate the differential gene expression of TIM-1 and TIM-3 as well as a few Th1 and Th2 cytokines (IL-2, IFN-γ, IL-4, IL-5 and IL-13) in CD4+ T cells isolated from bronchoalveolar lavage fluid (BALF) of patients (n = 28) and healthy controls (n = 8). Using flow cytometry, we were also able to analyse TIM-3 protein expression in 10 patients and 6 healthy controls.Results
A decreased TIM-3 mRNA (p < 0.05) and protein (p < 0.05) expression was observed in patients, and the level of TIM-3 mRNA correlated negatively with the CD4/CD8 T cell ratio in BALF cells of patients. Compared to a distinct subgroup of patients i.e. those with Löfgren''s syndrome, BALF CD4+ T cells from non- Löfgren''s patients expressed decreased mRNA levels of TIM-1 (p < 0.05). mRNA expression of IL-2 was increased in patients (p < 0.01) and non-Löfgren''s patients expressed significantly higher levels of IFN-γ mRNA (p < 0.05) versus patients with Löfgren''s syndrome.Conclusion
These findings are the first data on the expression of TIM-1 and TIM-3 molecules in sarcoidosis. The reduced TIM-3 expression in the lungs of patients may result in a defective T cell ability to control the Th1 immune response and could thus contribute to the pathogenesis of sarcoidosis. The down-regulated TIM-1 expression in non-Löfgren''spatients is in agreement with an exaggerated Th1 response in these patients. 相似文献49.
Mahdavi A Sajedi RH Asghari SM Taghdir M Rassa M 《International journal of biological macromolecules》2011,49(5):1038-1045
A comparative biochemical and structural study was performed on a cold active α-amylase from Bacillus cereus (BCA) and two well-known homologous mesophilic and thermophilic α-amylases from Bacillus amyloliquefaciens (BAA) and Bacillus licheniformis (BLA). In spite of a high degree of sequence and structural similarity, drastic variations were found for Topt as 50, 70 and 90 °C for BCA, BAA and BLA, respectively. The half-lives of thermoinactivation were 1 and 9 min for BCA and BAA at 80 °C respectively, whilst there was no inactivation for BLA at this temperature. Thermodynamic studies on inactivation process suggested that lower thermostability of BCA is due to lower inactivation slope of the Arrhenius plots and subsequently, lower Ea and ΔH#. Increased Km and accessible surface area for catalytic residues along with a decreased number of internal interactions in this region in BCA compared to BLA suggest that BCA substrate-binding site might be temperature sensitive and is probably more flexible. On the other hand, fewer ion pairs, destructive substitutions and disruption of aromatic interaction networks in structurally critical regions of Bacillus α-amylases result in a severe decrease in BCA thermostability compared to its mesophilic and thermophilic homologues. 相似文献
50.
Chhabra S Narang R Lakshmy R Vasisht S Agarwal DP Srivastava LM Manchanda SC Das N 《Molecular and cellular biochemistry》2004,259(1-2):59-66
Various population studies have reported the association of rare S2 allele of apolipoprotein C3 (APOC3) SstI polymorphism with hypertriglyceridemia (HTG) and coronary artery disease (CAD). We were the first to report an association of S2 allele with high triglyceride (TG) levels in healthy volunteers from Northern India. Since HTG is suggested to be a predominant risk factor for CAD among Indians, we have elucidated the relationship of APOC3 SstI polymorphism with the lipid profile and CAD. A total of 158 patients with > or = 70% stenosis in one or more coronary artery (angiographically proven CAD patients), 35 subjects with < 70% stenosis (NCAD) and 151 normal controls (free of heart disease) from Northern plains of India were recruited in the study. DNA samples were analyzed by polymerase chain reaction (PCR) followed by SstI digestion. Lipid profile was estimated by enzymatic kit. We found a strong association of S2 allele with high TG levels, which was more significant in patients. Prevalence of S2 allele in normal controls and CAD patients were comparable, despite the fact that mean TG level was significantly higher in patients. A greater insight into this observation revealed that the prevalence of high TG, if not coupled with other risk factors (like high total cholesterol, low HDL), was comparable in patients and controls. Thus, our study reveals that rare S2 allele may be employed as a susceptibility marker for high TG. However, high TG or S2 allele alone may not contribute to the etiology of CAD. 相似文献