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751.
C. Subathra Devi V. Mohanasrinivasan Pragya Sharma Daria Das B. Vaishnavi S. Jemimah Naine 《International journal of peptide research and therapeutics》2016,22(2):263-269
Nattokinase (NK) is a potent fibrinolytic enzyme with the potential for fighting against cardiovascular diseases. In this study, UV mutated Pseudomonas aeruginosa CMSS was used for production, purification and to study the stability of the enzyme. The enzyme was subjected to step by step purification by ammonium sulphate precipitation, dialysis, ion-exchange chromatography and gel filtration chromatography. The purified NK showed 91.84 % of clot lysis, comparable to standard streptokinase. The stability of the purified enzyme was analysed by different parameters such as pH, temperature, metal ions, surfactants and organic solvents. The molecular weight of the enzyme was determined as 27 kDa by SDS-PAGE and confirmed by fibrin zymography. The enzyme obtained its highest activity at pH 5 and at 45 °C. The present study showed the presence of fibrinolytic enzyme by its specificity. Further analysis of the biochemical properties and the precise mechanism of fibrinolytic enzymes will expand the scope of research for development of therapeutic agents to treat thrombosis. 相似文献
752.
Daria V. Fedyukina Theodore S. Jennaro Silvia Cavagnero 《The Journal of biological chemistry》2014,289(10):6740-6750
Ribosomes are large and highly charged macromolecular complexes consisting of RNA and proteins. Here, we address the electrostatic and nonpolar properties of ribosomal proteins that are important for ribosome assembly and interaction with other cellular components and may influence protein folding on the ribosome. We examined 50 S ribosomal subunits from 10 species and found a clear distinction between the net charge of ribosomal proteins from halophilic and non-halophilic organisms. We found that ∼67% ribosomal proteins from halophiles are negatively charged, whereas only up to ∼15% of ribosomal proteins from non-halophiles share this property. Conversely, hydrophobicity tends to be lower for ribosomal proteins from halophiles than for the corresponding proteins from non-halophiles. Importantly, the surface electrostatic potential of ribosomal proteins from all organisms, especially halophiles, has distinct positive and negative regions across all the examined species. Positively and negatively charged residues of ribosomal proteins tend to be clustered in buried and solvent-exposed regions, respectively. Hence, the majority of ribosomal proteins is characterized by a significant degree of intramolecular charge segregation, regardless of the organism of origin. This key property enables the ribosome to accommodate proteins within its complex scaffold regardless of their overall net charge. 相似文献
753.
754.
Zbigniew Adamski Daria Korolczuk Magdalena Purgiel Anna Grewling Marlena Ratajczak Micha? Bankiet Kazimierz Ziemnicki 《Biologia》2009,64(1):197-202
The effect of four sublethal concentrations (from 0.01165 to 0.3025 μg per insect, responding to LC10/10, LC10, LC30 and LC50) of the organophosphorus insecticide, fenitrothion, on Spodoptera exigua (Lepidoptera, Noctuidae) larval development and ultrastructure of follicular cells of adult female moths was tested. The
most prominent malformations were: breaks in the cuticle, increased mortality during larval/pupal molting, alterations of
nuclear envelope, changed heterochromatin pattern and abnormalities in mitochondrial ultrastructure. Some of the alterations
are dose-dependent, but the other ones, like organization of rough endoplasmic reticulum (RER), show non-linear response:
cells exposed to lower concentrations (LC10/10 and LC10) of the insecticide possessed clusters of accumulated RER, which were absent within the cells exposed to higher ones (LC30 and LC50). Formation of the eggshell was also markedly postponed within the groups exposed to lower doses. These findings prove that
even minute amounts of xenobiotics may cause significant changes within exposed populations. 相似文献
755.
756.
Two isoforms of Drosophila TRF2 are involved in embryonic development, premeiotic chromatin condensation, and proper differentiation of germ cells of both sexes 下载免费PDF全文
757.
Akritopoulou-Zanze I Darczak D Sarris K Phelan KM Huth JR Song D Johnson EF Jia Y Djuric SW 《Bioorganic & medicinal chemistry letters》2006,16(1):96-99
We report the synthesis of kinase targeted libraries based on the thienopyrazole scaffold. Several thienopyrazole analogs have been identified as submicromolar inhibitors of KDR. 相似文献
758.
Gubała E Olczyk T Pawlaczek A Handkiewicz-Junak D Roskosz J Krajewska J Zeman M Chmielik E Kukulska A Czarniecka A Włoch J 《Endokrynologia Polska》2006,57(4):396-402
INTRODUCTION: In differentiated thyroid cancer (DTC) the differentiation between reactive and metastatic lymph nodes is difficult at the early stages of metastasis. The aim of the study was to assess the results of fine needle aspiration (FNA) samples examination by the use of RT-PCR for Tg mRNA. The special attention was directed to the evaluation of specificity of TgRNA estimation. MATERIAL AND METHODS: The group consisted of 193 DTC patients with suspicion of lymph node recurrence and at least one positive RT-PCR result. Thyroglobulin RT-PCR was conducted in residual material left after preparation of cytological smears from FNA specimens. Primer spanning exons 3-5 were used with 39 cycles of PCR. RNA isolation control and cDNA amplification were carried out using GAPDH starters. 308 lymph node biopsies were included. RESULTS: 246 positive results for Tg RNA were observed in the analyzed group, 71.1% confirmed by FNA. Among other 71 results, in which cytological examination did not correspond unequivocally to molecular findings, in 34 metastases were confirmed both by cytological and clinical examination. There were 11 patients operated due to the positive serial molecular examination only. In 10 (91%) of them DTC metastases were confirmed. So, the positive predictive value of the molecular result ranged between 75-89% and the negative one was 100%. CONCLUSIONS: In DTC patients RT-PCR Tg mRNA is helpful in qualification of suspicious lymph nodes to surgery in DTC patients. At the negative cytological finding, the positive molecular result constitutes an indication for early surgery. 相似文献
759.
Pasalić D Ferencak G Grsković B Sesto M Stavljenić-Rukavina A 《Collegium antropologicum》2006,30(3):549-554
This study was performed to assess the effect of the S447X and Hind III lipoprotein lipase gene polymorphisms on development of coronary artery disease and hypertriglyceridemia. The study included 132 patients and 98 healthy control subjects of Croatian descent. The lipoprotein lipase S447X polymorphism was associated with coronary artery disease and hypertriglyceridemia, as indicated by the lower frequency of S447 allele in the patient group (p = 0.005) and odds ratio (O.R = 0.40, p = 0.006). The patient and control groups also showed a significant difference in the distribution of Hind III/S447X genotype combinations (p = 0.013). There were no significant associations with lipid parameters for any genotype or genotype combination in the patient group. Frequencies of the S447X polymorphism and S447X/Hind III combinations differed between the CAD/TG and control group, thus these polymorphisms may be associated with CAD and hypertriglyceridemia. 相似文献
760.
Pasalić D Marinković N Grsković B Ferencak G Bernat R Stavljenić-Rukavina A 《Molecular biology reports》2009,36(4):775-780
Human C-reactive protein (CRP) is a reactant involved in the acute phase response and one of the many molecular factors involved
in pathogenesis of coronary artery disease (CAD). CRP gene variants potentially mediate CRP plasma concentrations and the
development of CAD. 220 Croatian subjects with angiographically confirmed CAD and 132 control subjects were included in the
study. CRP gene polymorphisms 1059G/C and -717G/A were determined by RFLPs, using MaeIII and KspI endonuclease, respectively. Plasma concentrations of CRP and homocysteine were determined by immunoturbidimetry and FPIA,
respectively. CRP 1059G/C gene variants were significantly associated with CAD (OR = 0.50; 95% CI = 0.27, 0.94; P = 0.032). Wild GG genotype and rare allele C carrier genotypes were 184 and 22 in CAD(+) group, and 101 and 24 in CAD(−)
group, respectively. Multivariate analysis with age, gender, BMI, smoking status, hypertension and diabetes as covariates
showed that 1059C carriers had lower CRP concentrations in CAD(−) (P = 0.010) and CAD(+) subjects (P = 0.028). This allele was also significantly associated with lower plasma homocysteine concentrations in both groups (P = 0.018 for CAD(−) and 0.002 for CAD(+). There was no significant difference between CAD(+) and CAD(−) subjects in absolute
frequencies for CRP -717A/G gene variant, but multivariate analysis showed that carriers of the rarer G allele had significantly
higher CRP plasma concentrations in CAD(−) subjects (P = 0.031) and higher homocysteine concentrations in CAD(+) group (P < 0.001). Atherosclerosis is an inflammatory disease resulting from different genetic and environmental factors. Results
presented here support the contribution of CRP genetic variations in the development of CAD. 相似文献