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1.

Background  

Substituted catechols are important precursors for large-scale synthesis of pharmaceuticals and other industrial products. Most of the reported chemical synthesis methods are expensive and insufficient at industrial level. However, biological processes for production of substituted catechols could be highly selective and suitable for industrial purposes.  相似文献   
2.
Summary A total of 20 patients with advanced colorectal cancer received recombinant leukocyte interferon-A (rIFNA) either chronically (group I: twice a week up to 20×106 IU/m2 i.m.) or cyclically (group II: 1–4 periods of 8 consecutive days up to 20×106 IU/m2 i.m. daily at 20-days intervals) over a period of 12 weeks. There was 1 partial response, 1 mixed response and 1 patient with stable disease, whilst 17 patients had progressive disease. Median survival was 15.5 months. Survival was significantly shorter when the extent of hepatic disease was >25% (P=0.05), extrahepatic disease was extensive (P<0.005), alkaline phosphatase level was >2× normal (P<0.02), or performance status was <100% (P<0.001). Toxicity consisting mainly of fever, fatigue, anorexia and weight loss was serious in group I and minimal in group II. Administration of rIFNA led to a short lived augmentation of natural killer (NK) cell activity. In the cyclically treated group this was a recurrent phenomenon whereas a marked lasting depression of NK cell activity was seen in chronically treated patients. Interferon- production capacity was significantly stimulated during rIFNA therapy. The differences in toxicity and immunostimulatory effects between the two schedules may be of importance in the design of further studies.This trial was supported in part by Hoffmann-La Roche, Basle  相似文献   
3.
The production of reactive oxidants has been implicated in the pathology of a number of inflammatory conditions, including inflamed arthritic joints. Many assays for the detection of these oxidants in diseased states have been described, but there are a number of potential pitfalls in both experimental design and the interpretation of results obtained with these techniques. Here, we describe a number of commonly used assays to detect the production of reactive oxidants and critically discuss their usefulness and limitations. We focus on the role of xanthine oxidase in reactive oxidant production in inflammatory disease.  相似文献   
4.
A sensitive and specific method for the determination of diamines and polyamines by ion-pair high-performance liquid chromatography is described. The 5-dimethylaminonaphthalene-1-sulfonyl derivatives of putrescine, 1,6-diaminohexane, spermidine and spermine are separated on a μBondapak C15 reversed-phase column with 1-heptanesulfonic acid and acetonitrile as the mobile phase. All compounds are eluted within 30 min using a programmed solvent gradient system. The method has a lower detection limit of 1 pmole on column.Because of the simplicity of the method, its application provides a better means for closely monitoring patients undergoing treatment for various types of genito-urinary neoplastic diseases.  相似文献   
5.
Plant Cell, Tissue and Organ Culture (PCTOC) - In vitro regeneration of cotton seems to be highly genotype dependent and typically ensues through the extraordinarily complex mechanism of somatic...  相似文献   
6.
We hypothesized that elucidating the interactome of epidermal growth factor receptor (EGFR) forms that are mutated in lung cancer, via global analysis of protein–protein interactions, phosphorylation, and systematically perturbing the ensuing network nodes, should offer a new, more systems‐level perspective of the molecular etiology. Here, we describe an EGFR interactome of 263 proteins and offer a 14‐protein core network critical to the viability of multiple EGFR‐mutated lung cancer cells. Cells with acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) had differential dependence of the core network proteins based on the underlying molecular mechanisms of resistance. Of the 14 proteins, 9 are shown to be specifically associated with survival of EGFR‐mutated lung cancer cell lines. This included EGFR, GRB2, MK12, SHC1, ARAF, CD11B, ARHG5, GLU2B, and CD11A. With the use of a drug network associated with the core network proteins, we identified two compounds, midostaurin and lestaurtinib, that could overcome drug resistance through direct EGFR inhibition when combined with erlotinib. Our results, enabled by interactome mapping, suggest new targets and combination therapies that could circumvent EGFR TKI resistance.  相似文献   
7.
Design and synthesis of a few novel methylamino piperidinyl substituted oxazolidinones are reported. Their antibacterial activities have been evaluated in a MIC assay against broader panel of both susceptible and resistant Gram-positive strains. (S)-N-{3-[3-Fluoro-4-(methyl-{1-[3-(5-nitrofuran-2-yl)-acryloyl]-piperidin-4-yl}-amino)-phenyl]-2-oxo-oxazolidin-5-ylmethyl}-acetamide 4i has shown comparable antibacterial activity to linezolid and eperezolid in the MIC assay, additionally compound 4i showed good antibacterial activity with an in vitro MIC value of 2-4 microg/mL against linezolid resistant Staphylococcus aureus (linezolid 16 microg/mL).  相似文献   
8.
A rapid and sensitive high-performance liquid chromatographic method was developed for determination of diclofenac and its major metabolite, 4'-hydroxydiclofenac, in serum from rats treated with diclofenac. The method is simple with a one-step extraction procedure, isocratic HPLC separation, and UV detection at 280 nm. Use of N-phenylanthranilic acid as the internal standard provided good accuracy without interference by endogenous compounds or 5-hydroxydiclofenac, another metabolite of interest. Limits of detection for diclofenac and 4'-hydroxydiclofenac were 0.0225 and 0.0112 microg/ml, respectively. Average extraction efficiencies of diclofenac, 4'-hydroxydiclofenac, and the internal standard were >/=76%. The method was applied to serum collected at 3h after rats were treated with an experimentally useful dosage range of 3, 10 and 50mg/kg diclofenac. Recovery (as a percentage of dose) for the 4'-hydroxy metabolite in serum was found to consistently average from 0.10 to 0.12% following each dosage, whereas recovery of diclofenac in serum declined from 0.45 to 0.37%. Thus, the method is suitable for measurement of a major diclofenac metabolite in experimental studies.  相似文献   
9.
Androgen deprivation therapy has been the standard of care in prostate cancer due to its effectiveness in initial stages. However, the disease recurs, and this recurrent cancer is referred to as castration-resistant prostate cancer (CRPC). Radiotherapy is the treatment of choice; however, in addition to androgen independence, CRPC is often resistant to radiotherapy, making radioresistant CRPC an incurable disease. The molecular mechanisms by which CRPC cells acquire radioresistance are unclear. Androgen receptor (AR)-tyrosine 267 phosphorylation by Ack1 tyrosine kinase (also known as TNK2) has emerged as an important mechanism of CRPC growth. Here, we demonstrate that pTyr(267)-AR is recruited to the ATM (ataxia telangiectasia mutated) enhancer in an Ack1-dependent manner to up-regulate ATM expression. Mice engineered to express activated Ack1 exhibited a significant increase in pTyr(267)-AR and ATM levels. Furthermore, primary human CRPCs with up-regulated activated Ack1 and pTyr(267)-AR also exhibited significant increase in ATM expression. The Ack1 inhibitor AIM-100 not only inhibited Ack1 activity but also was able to suppress AR Tyr(267) phosphorylation and its recruitment to the ATM enhancer. Notably, AIM-100 suppressed Ack1 mediated ATM expression and mitigated the growth of radioresistant CRPC tumors. Thus, our study uncovers a previously unknown mechanism of radioresistance in CRPC, which can be therapeutically reversed by a new synergistic approach that includes radiotherapy along with the suppression of Ack1/AR/ATM signaling by the Ack1 inhibitor, AIM-100.  相似文献   
10.
ABSTRACT: BACKGROUND: Chikungunya (CHIK) is currently endemic in South and Central India and exist as co-infections with dengue in Northern India. In 2010, New Delhi witnessed an outbreak of CHIK in the months October-December. This was the first incidence of a dominant CHIK outbreak in Delhi and prompted us to characterize the Delhi virus strains. We have also investigated the evolution of CHIK spread in India. FINDINGS: Clinical samples were subjected to RT-PCR to detect CHIK viral RNA. The PCR amplified products were sequenced and the resulting sequences were genetically analyzed. Phylogenetic analysis based on partial sequences of the structural proteins E1 and E2 revealed that the viruses in the latest outbreak exhibited ECSA lineage. Two novel mutations, E1 K211E and E2 V264A were observed in all Delhi isolates. In addition, CHIKV sequences from eight states in India were analyzed along with Delhi sequences to map the genetic diversity of CHIKV within the country. Estimates of average evolutionary divergence within states showed varying divergence among the sequences both within the states and between the states. We identified distinct molecular signatures of the different genotypes of CHIKV revealing emergence of a new signature in the New Delhi clade. Statistical analyses and construction of evolutionary path of the virus within the country revealed gradual spread of one specific strain all over the country. CONCLUSION: This study has identified unique mutations in the E1 and E2 genes and has revealed the presence of ancestral CHIKV population with maximum diversity circulating in Maharashtra. The study has further revealed the trend of CHIK spread in India since its first report in 1963 and its subsequent reappearance in 2005.  相似文献   
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