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71.
Bahaa T. Shawky Manal G. Mahmoud Eman A. Ghazy Mohsen M.S. Asker Gada S. Ibrahim 《Journal of Genetic Engineering and Biotechnology》2011,9(1):59-63
Rice straw and corn stalks were used as fermentation substrate for the evaluation of cellulases activity secreted by different organisms. The substrates were pretreated with alkaline hydrogen peroxide (AHP) for 6 h at 30 and 60 °C. From the fermentation studies, rice straw and corn stalks substrates showed the highest cellulases activity after 96 h at 60 °C of pre-treatment. 相似文献
72.
ISB recommendation on definitions of joint coordinate systems of various joints for the reporting of human joint motion--Part II: shoulder, elbow, wrist and hand 总被引:14,自引:0,他引:14
Wu G van der Helm FC Veeger HE Makhsous M Van Roy P Anglin C Nagels J Karduna AR McQuade K Wang X Werner FW Buchholz B;International Society of Biomechanics 《Journal of biomechanics》2005,38(5):981-992
In this communication, the Standardization and Terminology Committee (STC) of the International Society of Biomechanics proposes a definition of a joint coordinate system (JCS) for the shoulder, elbow, wrist, and hand. For each joint, a standard for the local axis system in each articulating segment or bone is generated. These axes then standardize the JCS. The STC is publishing these recommendations so as to encourage their use, to stimulate feedback and discussion, and to facilitate further revisions. Adopting these standards will lead to better communication among researchers and clinicians. 相似文献
73.
Chemical modification of lysine residues in glucose oxidase was carried out using citraconic anhydride. Modification brought about changes in the kinetic properties of the enzyme as evident by substantial lowering of V(max) and K(m). Enhancement of tryptophan fluorescence was observed with a dramatic change in its pH dependence due to modification. Near- and far-UV circular dichroism spectra of the native and modified forms suggested formation of molten globule-like structures, further supported by 8-anilino-1-naphthalenesulfonic acid fluorescence which indicated higher exposure of hydrophobic residues as a result of chemical modification. 相似文献
74.
Peña-Diaz J Akbari M Sundheim O Farez-Vidal ME Andersen S Sneve R Gonzalez-Pacanowska D Krokan HE Slupphaug G 《Journal of molecular biology》2004,342(3):787-799
Enzymes involved in genomic maintenance of human parasites are attractive targets for parasite-specific drugs. The parasitic protozoan Trypanosoma cruzi contains at least two enzymes involved in the protection against potentially mutagenic uracil, a deoxyuridine triphosphate nucleotidohydrolase (dUTPase) and a uracil-DNA glycosylase belonging to the highly conserved UNG-family. Uracil-DNA glycosylase activities excise uracil from DNA and initiate a multistep base-excision repair (BER) pathway to restore the correct nucleotide sequence. Here we report the biochemical characterisation of T.cruzi UNG (TcUNG) and its contribution to the total uracil repair activity in T.cruzi. TcUNG is shown to be the major uracil-DNA glycosylase in T.cruzi. The purified recombinant TcUNG exhibits substrate preference for removal of uracil in the order ssU>U:G>U:A, and has no associated thymine-DNA glycosylase activity. T.cruzi apparently repairs U:G DNA substrate exclusively via short-patch BER, but the DNA polymerase involved surprisingly displays a vertebrate POLdelta-like pattern of inhibition. Back-up UDG activities such as SMUG, TDG and MBD4 were not found, underlying the importance of the TcUNG enzyme in protection against uracil in DNA and as a potential target for drug therapy. 相似文献
75.
Chater S Abdelmelek H Pequignot JM Sakly M Rhouma KB 《Electromagnetic biology and medicine》2006,25(3):135-144
This study investigated the effects of a static magnetic field (SMF) on hematopoiesis and biochemical parameters in female rats. Pregnant rats were exposed to SMF (128 mT-1 hour/day from day 6 to day 19 of pregnancy). At 25 degrees C, the exposure of rats 1 hour/day for 13 consecutive days to SMF induced an increase in hematocrit (Ht) level (+6%, p < 0.05), hemoglobin (Hb) concentration (+12%, p < 0.05) and LDH levels (67%, p < 0.05 ), suggesting an hypoxia-like state. Moreover, exposure to SMF increased blood glucose and decreased insulin release, leading to a diabetic-like state in pregnant rats. 相似文献
76.
Chao-Mei Ma Takuya Kawahata Masao Hattori Toru Otake Lili Wang Mohsen Daneshtalab 《Bioorganic & medicinal chemistry》2010,18(2):863-869
In our continued research on chlorogenic acid analogues and derivatives with improved bioactivity, we have synthesized some caffeoyl 5,6-anhydroquinic acid derivatives. The 1,7 acetonides of chlorogenic acid (15), and of the mono-caffeoyl 5,6-anhydroquinic acids (7–8) showed appreciable anti-HIV activity. The 3,4-dicaffeoyl 5,6-anhydroquinic acid (12) exhibited an anti-HIV activity twice as that of 3,5-dicaffeoylquinic acid (22). The caffeoyl 5,6-anhydroquinic acid derivatives displayed potent anti-oxidant activities. The mono-caffeoyl 5,6-anhydroquinic acids (10–11) were more than twice stronger than chlorogenic acid (21) on SOD-like activity. 相似文献
77.
Hamid Irannejad Mohsen Amini Fariba Khodagholi Niloufar Ansari Solaleh Khoramian Tusi Mohammad Sharifzadeh Abbas Shafiee 《Bioorganic & medicinal chemistry》2010,18(12):4224-4230
The role of novel triazine derivatives against oxidative stress exerted by hydrogen peroxide on differentiated rat pheochromocytoma (PC12) cell line was examined and a consistent protection from H2O2-induced cell death, associated with a marked reduction in caspase-3 activation, was observed. Moreover, activation of NF-κB, a known regulator of a host of genes that involves in specific stress and inflammatory responses by H2O2, was greatly impaired by triazine pretreatment in differentiated PC12 cells. Neuroprotective effect of such compounds may represent a promising approach for treatment of neurodegenerative diseases. 相似文献
78.
Salemi Z Hosseinkhani S Ranjbar B Nemat-Gorgani M 《Journal of biochemistry and molecular biology》2006,39(5):636-641
Our previous studies indicated that native carbonic anhydrase does not interact with hydrophobic adsorbents and that it acquires this ability upon denaturation. In the present study, an apo form of the enzyme was prepared by removal of zinc and a comparative study was performed on some characteristic features of the apo and native forms by far- and near-UV circular dichroism (CD), intrinsic fluorescent spectroscopy, 1-anilino naphthalene-8-sulfonate (ANS) binding, fluorescence quenching by acrylamide, and Tm measurement. Results indicate that protein flexibility is enhanced and the hydrophobic sites become more exposed upon conversion to the apo form. Accordingly, the apo structure showed a greater affinity for interaction with hydrophobic adsorbents as compared with the native structure. As observed for the native enzyme, heat denaturation of the apo form promoted interaction with alkyl residues present on the adsorbents and, by cooling followed by addition of zinc, catalytically-active immobilized preparations were obtained. 相似文献
79.
Naderi N Majidi M Mousavi Z Khoramian Tusi S Mansouri Z Khodagholi F 《Neurochemical research》2012,37(4):778-785
Most of the modulating effects of cannabinoids on pain are through putative cannabinoid CB1 and CB2 receptors. However, the
involvement of other receptors is also suggested. Cannabinoid compounds with analgesic activity such as palmitoylethanolamide
(PEA) show low affinity to CB1 and CB2 receptors, yet selectively activate GPR55 receptors. The objective of the present study
was to evaluate the possible role of spinal CB1 and GPR55 receptors on antinociceptive activity of PEA in formalin test as
well as in the spinal expression of IL1-β in rat. Intrathecal (i.t.) administration of PEA (1, 10 μg) significantly decreased
both pain-related scores in formalin test and IL1-β expression in rat spinal cord. Pretreatment of rats with low doses of
CB1 receptor antagonist/GPR55 receptor agonist AM251 (10, 100 ng; i.t.), did not attenuated the effect of PEA, yet even significantly
increased the effect of PEA on IL1-β expression in rat spinal cord. Interestingly, i.t. administration of low doses of AM251
per se significantly decreased both pain related behavior and spinal IL1-β expression in formalin test. These findings suggest
the possible involvement of receptors other than CB1 receptors in spinal pain pathways, such as GPR55, in pain modulating
activity of cannabinoids. 相似文献
80.
Hashemi M Eskandari-Nasab E Fazaeli A Rezaei H Mashhadi MA Arbabi F Taheri M 《Gene》2012,505(1):176-179
Caspase-8 (CASP8) plays a critical role in regulating apoptosis, and its functional polymorphisms may modify cancer risk. We investigated the possible association between CASP8 -652 6N ins/del (rs3834129) and the risk of breast cancer in a sample of Iranian population. This case-control study was done on 236 breast cancer patients and 203 cancer free healthy female. We designed a rapid and simple bi-directional PCR allele-specific amplification (bi-PASA) for detection of CASP8 -652 6N ins/del polymorphism. The results showed that the CASP8 -652 6N del/dl genotype was inversely associated with breast cancer risk (OR=0.33, 95% CI=0.17-0.65, p=0.001). The frequencies of the del allele in cases and controls were 29.1% and 38.6%, respectively. An inverse association between CASP8 6N del variant and the risk of breast cancer (OR=0.66, 95% CI=0.66-0.87, p=0.002) was found. In conclusion, the result suggests that the CASP8 -652 6N del polymorphism plays a protective role in susceptibility to breast cancer in our population. Further studies in other populations with larger samples are needed to confirm these findings. 相似文献