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71.
72.
Phenol degradation by Bacillus cereus AKG1 MTCC9817 and AKG2 MTCC 9818 was investigated and degradation kinetics are reported for the free and Ca-alginate gel-immobilized systems. The optimal pH for maximum phenol degradation by immobilized AKG1 and AKG2 was found to be 6.7 and 6.9, respectively, while 3% alginate was optimum for both the strains. The degradation of phenol by free as well as immobilized cells was comparable at lower concentrations of phenol (100–1000 mg l−1). However, the degradation efficiency of the immobilized strains was higher than that of the free strains at higher phenol concentrations (1500–2000 mg l−1), indicating the improved tolerance of the immobilized cells toward phenol toxicity. More than 50% of 2000 mg l−1 phenol was degraded by immobilized AKG1 and AKG2 within 26 and 36 days, respectively. Degradation kinetics of phenol by free and immobilized cells are well represented by the Haldane and Yano model.  相似文献   
73.

Background and aims

Sustained interaction of advanced glycation end products (AGEs) with their receptor RAGE and subsequent signaling plays an important role in the development of diabetic complications. Genetic variation of RAGE gene may be associated with the development of vascular complications in type 2 diabetes mellitus (T2DM).

Objectives

The present study aimed to explore the possible association of RAGE gene polymorphisms namely − 374T/A, − 429T/C and G82S with serum level of AGEs, paraoxonase (PON1) activity and macro-vascular complications (MVC) in Indian type 2 diabetes mellitus patients (T2DM).

Methods

A total of 265 diabetic patients, including DM without any complications (n = 135), DM-MVC (n = 130) and 171 healthy individuals were enrolled. Genotyping of RAGE variants were assessed by polymerase chain reaction-restriction fragment length polymorphism. Serum AGEs were estimated by ELISA and fluorometrically. and PON1 activity was assessed spectrophotometrically.

Results

Of the three examined SNPs, association of − 429T/C polymorphism with MVC in T2DM was observed (OR = 3.001, p = 0.001) in the dominant model. Allele ‘A’ of − 374T/A polymorphism seems to confer better cardiac outcome in T2DM. Patients carrying C allele (− 429T/C) and S allele (G82S) had significantly higher AGEs levels. − 429T/C polymorphism was also found to be associated with low PON1 activity. Interaction analysis revealed that the risk of development of MVC was higher in T2DM patients carrying both a CC genotype of − 429T/C polymorphism and a higher level of AGEs (OR = 1.343, p = 0.040).

Conclusion

RAGE gene polymorphism has a significant effect on AGEs level and PON1 activity in diabetic subjects compared to healthy individuals. Diabetic patients with a CC genotype of − 429T/C are prone to develop MVC, more so if AGEs levels are high and PON1 activity is low.  相似文献   
74.
A simple agar diffusion method is developed where pure colony of Chlamydomonas sp. CRP7 was isolated from Chlorella sp. CB4 mixtures by passing through agar migration with a light exposure of 6,000 lux for 7 h. The main concept behind it is that Chlamydomonas has flagella and the rhodopsin pigment is attracted towards light. Thus the above two microalgae species can be separated from the mixtures as eye spot serves as a navigator and flagella serves as a propeller for Chlamydomonas spp. Further the genomic DNA was isolated and purified from the above mentioned two species after the separation from the mixtures. PCR amplification was carried out for ITS1, 5.8S and ITS2 regions. The amplified products were sequenced and the sequence analysis confirmed that they belong to Chlamydomonas sp. and Chlorella sp. This is an important augmentation for isolation and separation of microalgae.  相似文献   
75.
A Banerjee  H R Levy  G C Levy  W W Chan 《Biochemistry》1985,24(7):1593-1598
Transferred nuclear Overhauser effects were used to determine the conformations of ATP, CTP, and ITP bound to the regulatory site of aspartate transcarbamylase. The results are in accord with the predictions of the London-Schmidt model [London, R. E., & Schmidt, P. G. (1972) Biochemistry 11, 3136] and show that ATP and CTP bind in the anti conformation while ITP binds in the syn conformation.  相似文献   
76.
T O Sitz  N Banerjee  R N Nazar 《Biochemistry》1981,20(14):4029-4033
Naturally occurring differences in the nucleotide sequences of 5.8S ribosomal ribonucleic acids (rRNAs) from a variety of organisms have been used to study the role of specific nucleotides in the secondary structure and intermolecular interactions of this RNA. Significant differences in the electrophoretic mobilities of free 5.8S RNAs and the thermal stabilities of 5.8S--28S rRNA complexes were observed even in such closely related sequences as those of man, rat, turtle, and chicken. A single base transition from a guanylic acid residue in position 2 in mammalian 5.8S rRNA to an adenylic acid residue in turtle and chicken 5.8S rRNA results both in a more open molecular conformation and in a 5.8S--28S rRNA junction which is 3.5 degrees C more stable to thermal denaturation. Other changes such as the deletion of single nucleotides from either the 5' or the 3' terminals have no detectable effect on these features. The results support secondary structure models for free 5.8S rRNA in which the termini interact to various degrees and 5.8S--28S rRNA junctions in which both termini of the 5.8S molecule interact with the cognate high molecular weight RNA component.  相似文献   
77.
78.
Summary We have isolated a deletion mutation and a point mutation in the copB gene of the replication region Repl of the IncFI plasmid Co1V2-K94. Subsequently, this copB gene with and without point mutation was cloned and sequenced, and the point mutation was mapped in the coding region of copB with a change of one amino acid from arginine to serine. Furthermore, this copB mutant had an approximately 10-fold increase in copy number. The CopB-phenotype of Co1V2-K94 could be complemented in trans by the copB gene of coresident IncFII plasmids such as R1 and R538, but not R100, suggesting that ColV2-K94 and R1 or R538 contain the same copB allele.  相似文献   
79.
Human amniotic membrane (hAM) is a tissue containing cells with proven stem cell properties. In its decellularized form it has been successfully applied as nerve conduit biomaterial to improve peripheral nerve regeneration in injury models. We hypothesize that viable hAM without prior cell isolation can be differentiated towards the Schwann cell lineage to generate a possible alternative to commonly applied tissue engineering materials for nerve regeneration. For in vitro Schwann cell differentiation, biopsies of hAM of 8 mm diameter were incubated with a sequential order of neuronal induction and growth factors for 21 days and characterized for cellular viability and the typical glial markers glial fibrillary acidic protein (GFAP), S100β, p75 and neurotrophic tyrosine kinase receptor (NTRK) using immunohistology. The secretion of the neurotrophic factors brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF) was quantified by ELISA. The hAM maintained high viability, especially under differentiation conditions (90.2 % ± 41.6 day 14; 80.0 % ± 44.5 day 21 compared to day 0). Both, BDNF and GDNF secretion was up-regulated upon differentiation. The fresh membrane stained positive for GFAP and p75 and NTRK, which was strongly increased after culture in differentiation conditions. Especially the epithelial layer within the membrane exhibited a change in morphology upon differentiation forming a multi-layered epithelium with intense accumulations of the marker proteins. However, S100β was expressed at equal levels and equal distribution in fresh and cultured hAM conditions. Viable hAM may be a promising alternative to present formulations used for peripheral nerve regeneration.  相似文献   
80.
In celebration of the twentieth anniversary of the inception of the CCN society, and of the first post-Covid-19 live meeting, the executive board of the ICCNS had chosen Nice as the venue for the 11th International workshop on the CCN family of genes. On this occasion participation in the meeting was extended to colleagues from other cell signaling fields who were invited to present both an overview of their work and the future directions of their laboratory. Also, for the first time, the members of the JCCS Editorial Board were invited to participate in a JCCS special session during which all aspects of the journal « life » were addressed and opened to free critical discussion. The scientific presentations and the discussions that followed showed once more that an expansion of the session topics was beneficial to the quality of the meeting and confirmed that the ARBIOCOM project discussed last April in Nice was now on track to be launched in 2023. The participants unanimously welcomed Professor Attramadal’s proposition to organize the 2024, 12th International CCN workshop in Oslo, Norway.  相似文献   
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