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31.
Mandwal AK Tripathi CK Trivedi PD Joshi AK Agarwal SC Bihari V 《Biotechnology letters》2004,26(3):217-221
Conversion of benzaldehyde to L-phenylacetyl carbinol (L-PAC) was achieved with immobilized, growing cells of Saccharomyces cerevisiae in different reactors. Product formation increased (31%) with the subsequent initial reuses of the entrapped cells. Biomass production and PAC formation depleted (40 and 57%, respectively) after 4-5 continuous growth and biotransformation cycles. With the regeneration of the biocatalysts, catalytic activity of the cells was resumed. The highest yields were in a stirred tank reactor (29 g PAC) from 77 g benzeldehyde with 14 repeated uses of entrapped cells. 相似文献
32.
Kumar Khanna V 《Biotechnology advances》2007,25(1):85-98
The current status and research trends of detection techniques for DNA-based analysis such as DNA finger printing, sequencing, biochips and allied fields are examined. An overview of main detectors is presented vis-à-vis these DNA operations. The biochip method is explained, the role of micro- and nanoelectronic technologies in biochip realization is highlighted, various optical and electrical detection principles employed in biochips are indicated, and the operational mechanisms of these detection devices are described. Although a diversity of biochips for diagnostic and therapeutic applications has been demonstrated in research laboratories worldwide, only some of these chips have entered the clinical market, and more chips are awaiting commercialization. The necessity of tagging is eliminated in refractive-index change based devices, but the basic flaw of indirect nature of most detection methodologies can only be overcome by generic and/or reagentless DNA sensors such as the conductance-based approach and the DNA-single electron transistor (DNA-SET) structure. Devices of the electrical detection-based category are expected to pave the pathway for the next-generation DNA chips. The review provides a comprehensive coverage of the detection technologies for DNA finger printing, sequencing and related techniques, encompassing a variety of methods from the primitive art to the state-of-the-art scenario as well as promising methods for the future. 相似文献
33.
Vinod B Shidham Richard Komorowski Marcelle Neuberg Alonzo Walker Bruce H Campbell Chung-Che Chang William W Dzwierzynski 《Diagnostic pathology》2006,1(1):1-9
Background
Breast spindle cell tumours (BSCTs), although rare, represent a heterogeneous group with different treatment modalities. This work was undertaken to evaluate the utility of fine needle aspiration cytology (FNAC), histopathology and immunohistochemistry (IHC) in differentiating BSCTs.Methods
FNAC of eight breast masses diagnosed cytologically as BSCTs was followed by wide excision biopsy. IHC using a panel of antibodies against vimentin, pan-cytokeratin, s100, desmin, smooth muscle actin, CD34, and CD10 was evaluated to define their nature.Results
FNAC defined the tumors as benign (n = 4), suspicious (n = 2) and malignant (n = 3), based on the cytopathological criteria of malignancy. Following wide excision biopsy, the tumors were reclassified into benign (n = 5) and malignant (n = 3). In the benign group, the diagnosis was raised histologically and confirmed by IHC for 3 cases (one spindle cell lipoma, one myofibroblastoma and one leiomyoma). For the remaining two cases, the diagnosis was set up after IHC (one fibromatosis and one spindle cell variant of adenomyoepithelioma). In the malignant group, a leiomyosarcoma was diagnosed histologically, while IHC was crucial to set up the diagnosis of one case of spindle cell carcinoma and one malignant myoepithelioma.Conclusion
FNAC in BSCTs is an insufficient tool and should be followed by wide excision biopsy. The latter technique differentiate benign from malignant BSCTs and is able in 50% of the cases to set up the definite diagnosis. IHC is of value to define the nature of different benign lesions and is mandatory in the malignant ones for optimal treatment. Awareness of the different types of BSCTs prevents unnecessary extensive therapeutic regimes. 相似文献34.
Studies using both Fisher 344 and Sprague-Dawley (SD) rat lines have shown that gestational and/or lactational maternal lead (Pb) exposure causes delayed reproductive maturation in their respective female offspring. Because these studies utilized different experimental regimens for dosing and for monitoring Pb levels, it has not been possible to determine which rat line provides the best model for low level Pb toxicity studies. This study was designed to address this issue. Adult Fisher and SD female rats were dosed with either a solution of PbAc containing 12 mg of Pb/ml or sodium acetate (NaAc) for controls. Dosing began 30 days prior to breeding and continued until their pups were weaned at 21 days of age. At the time of breeding and through weaning the blood lead (BPb) levels in the Fisher dams averaged 37.3 microg/dl and the SD dams averaged 29.9 microg/dl. Pb delayed the timing of puberty (p < 0.01) in Fisher offspring, and suppressed serum levels of luteinizing hormone (LH, p < 0.001) and estradiol (E2, p < 0.01). These effects did not occur in the SD offspring. Doubling the dose given to the SD rats increased their BPb levels to 62.6 microg/dl, yet there were still no effects noted. These results indicate that Fisher offspring are more sensitive to maternal Pb exposure with regard to puberty related insults than are SD rats, suggesting that the Fisher line may be a more reliable rodent model to study the effects of low level Pb toxicity. 相似文献
35.
Anil Chatterji Z. A. Ansari J. K. Mishra Parveen Rattan A. H. Parulekar 《Hydrobiologia》1995,310(2):157-161
The occurrence of Diaphanosoma excisum (Sars), a freshwater cladoceran, in benthic samples of an intertidal sandy beach is reported. Population density was seasonal. A relatively high density was recorded from June to September (south-west monsoon season) with a maximum (46 ind 10 cm–2) in September at a depth of 10–15 cm of sediment. A sudden decline occurred during north-east monsoon (October to January), and in the fair season (February to May), the cladocerans disappeared. Mean density varied (P<0.001) with sediment depth and season and showed a contagious dispersion. Abundance was negatively correlated with salinity (r = –0.76) but positively with POC (r =0.79) and mean grain size of the sediment (r = 0.93). The density of D. excisum was highest in fine sand. 相似文献
36.
Shouvik Das Hari D. Upadhyaya Deepak Bajaj Alice Kujur Saurabh Badoni Laxmi Vinod Kumar Shailesh Tripathi C. L. Laxmipathi Gowda Shivali Sharma Sube Singh Akhilesh K. Tyagi Swarup K. Parida 《DNA research》2015,22(3):193-203
A rapid high-resolution genome-wide strategy for molecular mapping of major QTL(s)/gene(s) regulating important agronomic traits is vital for in-depth dissection of complex quantitative traits and genetic enhancement in chickpea. The present study for the first time employed a NGS-based whole-genome QTL-seq strategy to identify one major genomic region harbouring a robust 100-seed weight QTL using an intra-specific 221 chickpea mapping population (desi cv. ICC 7184 × desi cv. ICC 15061). The QTL-seq-derived major SW QTL (CaqSW1.1) was further validated by single-nucleotide polymorphism (SNP) and simple sequence repeat (SSR) marker-based traditional QTL mapping (47.6% R2 at higher LOD >19). This reflects the reliability and efficacy of QTL-seq as a strategy for rapid genome-wide scanning and fine mapping of major trait regulatory QTLs in chickpea. The use of QTL-seq and classical QTL mapping in combination narrowed down the 1.37 Mb (comprising 177 genes) major SW QTL (CaqSW1.1) region into a 35 kb genomic interval on desi chickpea chromosome 1 containing six genes. One coding SNP (G/A)-carrying constitutive photomorphogenic9 (COP9) signalosome complex subunit 8 (CSN8) gene of these exhibited seed-specific expression, including pronounced differential up-/down-regulation in low and high seed weight mapping parents and homozygous individuals during seed development. The coding SNP mined in this potential seed weight-governing candidate CSN8 gene was found to be present exclusively in all cultivated species/genotypes, but not in any wild species/genotypes of primary, secondary and tertiary gene pools. This indicates the effect of strong artificial and/or natural selection pressure on target SW locus during chickpea domestication. The proposed QTL-seq-driven integrated genome-wide strategy has potential to delineate major candidate gene(s) harbouring a robust trait regulatory QTL rapidly with optimal use of resources. This will further assist us to extrapolate the molecular mechanism underlying complex quantitative traits at a genome-wide scale leading to fast-paced marker-assisted genetic improvement in diverse crop plants, including chickpea. 相似文献
37.
Cicerone Tudor Joost te Riet Christina Eich Rolf Harkes Nick Smisdom Jessica Bouhuijzen Wenger Marcel Ameloot Matthew Holt Johannes S. Kanger Carl G. Figdor Alessandra Cambi Vinod Subramaniam 《The Journal of biological chemistry》2014,289(19):13445-13460
Activated leukocyte cell adhesion molecule (ALCAM) is a type I transmembrane protein member of the immunoglobulin superfamily of cell adhesion molecules. Involved in important pathophysiological processes such as the immune response, cancer metastasis, and neuronal development, ALCAM undergoes both homotypic interactions with other ALCAM molecules and heterotypic interactions with the surface receptor CD6 expressed at the T cell surface. Despite biochemical and biophysical evidence of a dynamic association between ALCAM and the actin cytoskeleton, no detailed information is available about how this association occurs at the molecular level. Here, we exploit a combination of complementary microscopy techniques, including FRET detected by fluorescence lifetime imaging microscopy and single-cell force spectroscopy, and we demonstrate the existence of a preformed ligand-independent supramolecular complex where ALCAM stably interacts with actin by binding to syntenin-1 and ezrin. Interaction with the ligand CD6 further enhances these multiple interactions. Altogether, our results propose a novel biophysical framework to understand the stabilizing role of the ALCAM supramolecular complex engaged to CD6 during dendritic cell-T cell interactions and provide novel information on the molecular players involved in the formation and signaling of the immunological synapse at the dendritic cell side. 相似文献
38.
Deb C Daniel J Sirakova TD Abomoelak B Dubey VS Kolattukudy PE 《The Journal of biological chemistry》2006,281(7):3866-3875
Twenty-four putative lipase/esterase genes of Mycobacterium tuberculosis H37Rv were expressed in Escherichia coli and assayed for long-chain triacylglycerol (TG) hydrolase activity. We show here that the product of Rv3097c (LIPY) hydrolyzed long-chain TG with high specific activity. LIPY was purified after solubilization from inclusion bodies; the enzyme displayed a K(m) of 7.57 mM and V(max) of 653.3 nmol/mg/min for triolein with optimal activity between pH 8.0 and pH 9.0. LIPY was inhibited by active serine-directed reagents and was inactivated at temperatures above 37 degrees C. Detergents above their critical micellar concentrations and divalent cations inhibited the activity of LIPY. The N-terminal half of LIPY showed sequence homology with the proline glutamic acid-polymorphic GC-rich repetitive sequences protein family of M. tuberculosis. The C-terminal half of LIPY possesses amino acid domains homologous with the hormone-sensitive lipase family and the conserved active-site motif GDSAG. LIPY shows low sequence identity with the annotated lipases of M. tuberculosis and with other bacterial lipases. We demonstrate that hypoxic cultures of M. tuberculosis, which had accumulated TG, hydrolyzed the stored TG when subjected to nutrient starvation. Under such conditions, lipY was induced more than all lipases, suggesting a central role for it in the utilization of stored TG. We also show that in the lipY-deficient mutant, TG utilization was drastically decreased under nutrient-deprived condition. Thus, LIPY may be responsible for the utilization of stored TG during dormancy and reactivation of the pathogen. 相似文献
39.
Reduced heat shock response in human mononuclear cells during aging and its association with polymorphisms in HSP70 genes 总被引:3,自引:1,他引:3 下载免费PDF全文
Singh R Kølvraa S Bross P Jensen UB Gregersen N Tan Q Knudsen C Rattan SI 《Cell stress & chaperones》2006,11(3):208-215
Age-dependent changes in heat shock response (HSR) were studied in mononuclear cells (monocytes and lymphocytes) collected from young (mean age = 22.6 ± 1.7 years) and middle-aged (mean age = 56.3 ± 4.7 years) subjects after 1 hour of heat shock at 42°C. Genotype-specific HSR was measured by genotyping the subjects for 3 single nucleotide polymorphisms, HSPA1A(A-110C), HSPA1B(A1267G), and HSPA1L(T2437C), 1 each in the 3 HSP70 genes. A significant age-related decrease in the induction of Hsp70 occurred after heat shock in both monocytes and lymphocytes. The noninducible and inducible forms of Hsp70 decreased 1.3-fold (P < 0.001) and 1.4-fold (P < 0.001), respectively, in the monocytes with age. In the young subjects, a positive association was found between HSPA1L(T2437C) polymorphism and HSR. CC carriers had a significantly lower induction than TT carriers in both monocytes (P = 0.015) and lymphocytes (P = 0.044). This polymorphism, which is present in the coding region of HSPA1L gene, can affect the chaperoning function of Hsp70. These data consolidate our other observations that the CC genotype is unfavorable for human longevity and provide a functional explanation in terms of variations in HSR. 相似文献
40.
Shaun K. Morris Diego G. Bassani Rajesh Kumar Shally Awasthi Vinod K. Paul Prabhat Jha 《PloS one》2010,5(3)