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1.
Candida dubliniensis ia an opportunistic pathogen mainly associated with oral candidiasis in human immunodeficiency virus (HIV)-infected individuals. We recently recovered the first Italian clinical isolates of C. dubliniensis from the oral cavities of seven HIV-seropositive subjects. The in vitro susceptibility to fluconazole (FLCZ) of these isolates was determined according to the National Committee for Clinical Laboratory Standards (NCCLS) M27-A broth microdilution method for yeasts. All seven isolates of C. dubliniensis were susceptible to FLCZ (MICs < or =0.5 microg/ml). Results of this reference method were compared to those obtained with simplified tests, more adapted to routine evaluation in hospital laboratories. Fungitest and Sensititre YeastOne colorimetric microplate-based methods have been evaluated. The agar disk diffusion method has also been tested on two different media: RPMI 1640-2% glucose and High Resolution-2% glucose-0.5 microg/ml methylene blue. All of the simplified methods tested were able to correctly identify FLCZ-susceptibility of this group of Italian C. dubliniensis isolates.  相似文献   

2.
We have evaluated the FLIPR Calcium 3 Assay Kit (Calcium 3), a new no-wash fluorescence calcium indicator dye reagent, for the measurement of agonist-stimulated calcium signaling in cells expressing the serotonin 2C (5-HT(2C)), metabotropic glutamate receptor 5 (mGluR5) and the vasopressin 2 (V2) G-protein-coupled receptors. Calcium 3 yielded equivalent (5-HT(2C)) or superior (mGluR5 and V2) sensitivity to FLUO-4 as indexed by the change in fluorescence counts following agonist application. Assay variability, indexed by CV, using Calcium 3 or FLUO-4 was equivalent with 5-HT(2C) receptor responses although CVs were reduced using Calcium 3 in the examples of the mGluR5 and V2 receptors. Receptor pharmacologies based on agonist EC(50) values were identical when either Calcium 3 or FLUO-4 were utilized. Our results validate Calcium 3 as a compelling alternative to FLUO-4 in the choice of fluorescent dye reagent for studying G-protein-coupled receptors, providing the advantage of a homogenous, no-wash assay format.  相似文献   

3.
定量测定黑鲷生长激素受体mRNA的液相杂交/RNase保护法   总被引:4,自引:0,他引:4  
目的 建立液相杂交 核糖核酸酶保护测定 (RibonucleaseProtectionAssay,RPA)技术定量检测黑鲷(Sparusmacrocephalus)生长激素受体mRNA水平。方法 将黑鲷生长激素受体cDNA片断亚克隆至pGEM T载体 ,制备特异性的放射性反义RNA探针及正义RNA ,将反义RNA探针与正义RNA及样品总RNA进行液相杂交 ,用RNaseA和RNaseT1 降解杂交产物的单链RNA ,双链杂交体得到保护 ,然后检测杂交体的分子大小及放射强度。结果 检测出了黑鲷生长激素受体反义RNA探针与正义RNA及样品总RNA的特异性杂交片断 ,由此建立了定量测定黑鲷生长激素受体mRNA的液相杂交 RNase保护法 ,并采用该方法在黑鲷的多种组织中检测出了生长激素受体基因的表达 ,表达水平在肝脏中最高。该结果与我们曾采用生长激素放射受体分析法对黑鲷生长激素受体所研究的结果相吻合。结论 为进一步深入研究鱼类生长激素受体分子内分泌的调控理论提供了有力手段。  相似文献   

4.
The no-wash calcium assay kits developed by Molecular Devices Corporation have greatly enhanced the throughput of cell-based calcium mobilization high-throughput screening (HTS) assays and enabled screening using nonadherent cells. The fluorescent imaging plate reader (FLIPR) Calcium 3 Assay Kit, optimal for targets that have proteins or peptides as agonists, has 2 potential drawbacks: 1) a significant downward spike in fluorescence signal upon liquid transfer that can be the same magnitude as the agonist response, making data analysis difficult; and 2) medium removal is required for some targets, which essentially reintroduces a wash step. Several no-wash products were introduced in 2005. The authors compare the Fluo-4 NW Calcium Assay Kit and the BD Calcium Assay Kit with the FLIPR Calcium 3 Assay Kit using human native rhabdomyosarcoma cells expressing the urotensin-II receptor (UT). The BDtrade mark Calcium Assay Kit gives the best performance in the true no-wash mode, in which both agonist and antagonist activity are easily quantified. Although these new products provide additional options for measuring calcium mobilization, the different results observed with each kit, using the UT receptor as an example, suggest that one should characterize all dyes against each target in a systematic way prior to choosing one for HTS.  相似文献   

5.
DNA analysis of the low-density lipoprotein receptor gene of a young Brazilian man, suffering from an extreme form of hypercholesterolemia, revealed the presence of two mutations, thereby confirming the diagnosis of homozygous familial hypercholesterolemia (FH). The first mutation was a mutation frequently found in Brazilian patients with FH, termed C660X or FHLebanese. The second mutation, in which a serine residue was replaced by a cysteine at amino acid position 305 (S305C) was a new mutation never described before. S305C was inherited from the proband's mother, who was of Italian descent. The occurrence of LDL receptor gene mutations of Lebanese and Italian origin in Brazil underlines the genetic heterogeneity of the Brazilian population.  相似文献   

6.
Precise quantification and quality characterisation of isolated RNAs are prerequisites for their further exploitation in genome-wide microarrays, Northern blots, cDNA library preparation and others. Our data indicate that RNA analyses using Agilent RNA Nano Assay exhibit several advantages when compared with those performed on ethidium bromide-stained agarose gel electrophoresis or on a spectrophotometer. The RNA Nano Assay makes it possible to estimate RNA concentrations in the range from 1000 ng microl(-1) to 17 ng microl(-1). The presence of impurities including traces of DNA within RNA samples does not influence the concentration measurements. Like agarose gel electrophoresis, RNA Nano Assay allows to analyse RNAs dissolved in formamide and therefore protected against RNase action. Moreover, it allows a clearer distinction of partially degraded samples. The limitation of RNA Nano Assay is the impossibility to detect and to analyse double-stranded RNAs.  相似文献   

7.

Background

Monoclonal antibodies directed against the epidermal growth factor receptor (EGFR) have been approved for the treatment of patients with metastatic colorectal carcinoma (mCRC) that do not carry KRAS mutations. Therefore, KRAS testing has become mandatory to chose the most appropriate therapy for these patients.

Methodology/Principal Findings

In order to guarantee the possibility for mCRC patients to receive an high quality KRAS testing in every Italian region, the Italian Association of Medical Oncology (AIOM) and the Italian Society of Pathology and Cytopathology -Italian division of the International Academy of Pathology (SIAPEC-IAP) started a program to improve KRAS testing. AIOM and SIAPEC identified a large panel of Italian medical oncologists, pathologists and molecular biologists that outlined guidelines for KRAS testing in mCRC patients. These guidelines include specific information on the target patient population, the biological material for molecular analysis, the extraction of DNA, and the methods for the mutational analysis that are summarized in this paper. Following the publication of the guidelines, the scientific societies started an external quality assessment scheme for KRAS testing. Five CRC specimens with known KRAS mutation status were sent to the 59 centers that participated to the program. The samples were validated by three referral laboratories. The participating laboratories were allowed to use their own preferred method for DNA extraction and mutational analysis and were asked to report the results within 4 weeks. The limit to pass the quality assessment was set at 100% of true responses. In the first round, only two centers did not pass (3%). The two centers were offered to participate to a second round and both centers failed again to pass.

Conclusions

The results of this first Italian quality assessment for KRAS testing suggest that KRAS mutational analysis is performed with good quality in the majority of Italian centers.  相似文献   

8.
The bovine oxidized LDL receptor 1 (OLR1) was chosen as a candidate gene for association tests with milk composition traits. Genotyping of 773 Italian Brown Swiss for a SNP at position 8232 in OLR1 (NW_215807:g.8232C>A) revealed a frequency of 0.95 for the g.8232C allele. The University of Wisconsin Holstein resource population was genotyped for the OLR1 NW_215807:g.[7160C>T; 7161A>G; 8232C>A] SNPs, and four haplotypes were inferred based on the genotypes of sires and their daughters. Oxidized LDL receptor 1 haplotypes were significantly associated with fat percentage (P = 0.0015). Haplotype [C; A; C] was associated with a significant increase in fat percentage when compared with the other haplotypes.  相似文献   

9.
The C3b receptor of human erythrocytes is known to act as a cofactor for the cleavage of the complement protein C3b by the serine proteinase C3b/C4b Ina. The same cofactor activity is shown to be present on human tonsil B-lymphocytes. The cofactor activity of the C3b receptor can be assayed, on intact cells or in solubilized extracts of cells, by determining the rate of C3b cleavage in the presence of fixed concentrations of C3b and of C3b/C4b Ina. This assay method was used to compare the characteristics and relative quantities of C3b receptors on erythrocytes and lymphocytes. The cofactor activities associated with these two cell types resemble each other, but are distinct from the serum cofactor proteins, C4bp and Factor H, in antigenicity and in pH- and ionic-strength-dependence, and are distinct from Factor H in substrate specificity. Assay of cofactor activity in intact cells indicates that there are about 80-fold more receptors per cell on the lymphocyte surface than on erythrocytes. Assays with cells made permeable by detergent show that, whereas essentially all of the receptors on erythrocytes are on the cell surface, B-lymphocytes contain a large internal receptor pool, which makes up more than 80% of the total cofactor activity of the cell.  相似文献   

10.
Steroid receptor assays have clinical relevance in selecting women who would benefit from endocrine intervention. As the degree of benefit from endocrine therapy is directly related to the quantity of receptor present in the tumour, the quality of the steroid receptor assays is important. Moreover, since patients entered in multi-centre trials often include stratification based on the receptor status, receptor assays should be comparable between different institutes. ER- and PgR-assays have been evaluated in quality assessment studies for almost 20 years by the EORTC Receptor and Biomarker Study Group. During the QA trial 1998/1999 results were reported by 42 participants performing the Ligand Binding Assay (LBA) and by 39 participants using the Enzyme Immuno-Assay (EIA) kit. Each participant received a set of 12 QA vials to be analysed two at a time at two-monthly intervals. The between-laboratory CVs of ER LBA and EIA amounted to 40-50%. For PgR the between-lab CVs for the EIA method are lower as compared with LBA but still are approx. 30%. Notwithstanding the high deviation in reported values and the high between-lab CVs, the consistency of the participants over the year is acceptable, which pave the way for calibration. Indeed, after normalization of assay results the mean between-lab CVs dropped to 11% for ER LBA, 14% for ER EIA, 9% for PgR LBA and 11% for PgR EIA. Such a reduction of between-laboratory CVs is an essential requirement for the use of steroid receptor data in multicentre clinical studies.  相似文献   

11.
The synthesis and anticancer activity of 2-arylamino-6-trifluoromethyl-3-(hydrazonocarbonyl)pyridines is described. The new trifluoromethylpyridine derivatives were evaluated for their anticancer activity toward human cancer cell lines by the National Cancer Institute (NCI). Most of them had excellent growth inhibition activity, having GI50 values in the low micromolar to nanomolar concentration range. The most potent 2,6-dichlorobenzaldehydehydrazone 29 inhibited the growth of all tested cancer cell lines with nanomolar potency, and did not show animal toxicity. Hydrazone 29 has been selected by the Biological Evaluation Committee of NCI for testing in vivo Hollow Fiber Assay.  相似文献   

12.
This recommendation by the Italian Associations of Nuclear Medicine (AIMN) and Medical Physics (AIFM) focuses on the dosimetric optimization of Nuclear Medicine Therapy (NMT) as clearly requested by the article 56 of the EURATOM Directive 2013/59 and its consequent implementation in article 158 in the Italian Law n. 101/2020.However, this statement must deal with scientific and methodological limits that still exist and, above all, with the currently available limited resources. This paper addresses these specific issues. It distinguishes among many possible kinds of NMT. For each type, dosimetric optimization is recommended or considered optional, according to the general criteria adopted in any human choice, i.e. a check of technical feasibility first, followed by a cost/benefit argument. The classification of therapies as standardized or non-standardized is presented. This is based on the complexity of the type of pathology, on the variability of the treatment outcome, and on the risks involved.According to the present document, which was officially delivered to Italian Health Ministry as necessary interpretation of the law, a therapeutic team can, in science and consciousness, overcome the indications of posology, to optimize and tailoring a treatment with dosimetry, on the basis of published national or international data or guidelines, without need of an Ethics Committee approval. Data collected in this way will provide additional evidence about optimal dosimetric reference values.As conclusion, a formal appeal is made to the European and National regulatory agencies for pharmaceuticals to obtain the official acknowledgment of this principle.  相似文献   

13.
A sensitive and selective liquid chromatographic assay for determining the non-peptide endothelin A receptor antagonist PD 156707 (I) in rat plasma has been developed and validated. The analyte was isolated from matrix by solid-phase extraction. Liquid chromatographic separation was achieved isocratically ona 3.2 mm I.D., ODS column with a mobile hase of acetonitrile-ammonium phosphate (50 mM, pH 3.5) (44:56, v/v). Column effluent was monitored fluorometrically. Peak-height ratios (analyte/IS) were proportional to I concentrations in rat plasma from 25 to 1000 ng/ml. Assay precision and accuracy for I, based on quality controls, was 9.5% relative standard deviation, with relative error of ±6.5%. The quantitation limit was 25 ng/ml for a 200-μl sample aliquot.  相似文献   

14.
The Mouse Lymphoma Assay (MLA) Workgroup of the International Workshop on Genotoxicity Testing (IWGT), comprised of experts from Japan, Europe and the United States, met on September 9, 2005, in San Francisco, CA, USA. This meeting of the MLA Workgroup was devoted to reaching a consensus on issues involved with 24-h treatment. Recommendations were made concerning the acceptable values for the negative/solvent control (mutant frequency, cloning efficiency and suspension growth) and the criteria to define an acceptable positive control response. Consensus was also reached concerning the use of the global evaluation factor (GEF) and appropriate statistical trend analysis to define positive and negative responses for the 24-h treatment. The Workgroup agreed to continue their support of the International Committee on Harmonization (ICH) recommendation that the MLA assay should include a 24-h treatment (without S-9) in those situations where the short treatment (3-4 h) gives negative results.  相似文献   

15.
Inositol phosphates (IPs), such as 1,4,5-inositol-trisphosphate (IP(3)), comprise a ubiquitous intracellular signaling cascade initiated in response to G protein-coupled receptor-mediated activation of phospholipase C. Classical methods for measuring intracellular accumulation of these molecules include time-consuming high-performance liquid chromatography (HPLC) separation or large-volume, gravity-fed anion-exchange column chromatography. More recent approaches, such as radio-receptor and AlphaScreen assays, offer higher throughput. However, these techniques rely on measurement of IP(3) itself, rather than its accumulation with other downstream IPs, and often suffer from poor signal-to-noise ratios due to the transient nature of IP(3). The authors have developed a miniaturized, anion-exchange chromatography method for measuring inositol phosphate accumulation in cells that takes advantage of signal amplification achieved through measuring IP(3) and downstream IPs. This assay uses centrifugation of 96-well-formatted anion-exchange mini-columns for the isolation of radiolabeled inositol phosphates from cell extracts, followed by low-background dry-scintillation counting. This improved assay method measures receptor-mediated IP accumulation with signal-to-noise and pharmacological values comparable to the classical large-volume, column-based methods. Assay validation data for recombinant muscarinic receptor 1, galanin receptor 2, and rat astrocyte metabotropic glutamate receptor 5 are presented. This miniaturized protocol reduces reagent usage and assay time as compared to large-column methods and is compatible with standard 96-well scintillation counters.  相似文献   

16.
PLIN2 (perilipin 2) is a cytosolic protein that promotes the formation and stabilization of the intracellular lipid droplets, organelles involved in the storage of lipid depots. Porcine PLIN2 gene represents a biological and positional candidate for fat deposition, a polygenic trait that affects carcass and meat quality. The aim of the present study was to screen PLIN2 gene for polymorphisms, to evaluate the association with carcass quality traits, and to investigate the gene expression in skeletal muscle. Six new single nucleotide polymorphisms (SNP) were detected by sequencing 32 samples from five pig breeds (Italian Large White, Italian Duroc, Italian Landrace, Belgian Landrace, Pietrain). Two SNP localized in introns, two in the 3′-untranslated region (UTR), and two missense SNP were found in exons. A 3′-UTR mutation (GU461317:g.98G>A), genotyped in 290 Italian Duroc pigs by High Resolution Melting, resulted significantly associated (P < 0.01) with average daily gain, feed conversion ratio, lean cuts and hams weight estimated breeding values. PLIN2 gene expression analysis in skeletal muscle of Italian Large White and Italian Duroc pigs divergent for backfat thickness and visible intermuscular fat showed a trend of higher expression level in pigs with higher intermuscular fat. These results suggest that PLIN2 can be a marker for carcass quality in pigs. Further investigation at both gene and protein level could elucidate its role on fat deposition.  相似文献   

17.
The thyrotropin receptor (TSHR), lutropin receptor, and follitropin receptor are related members of the superfamily of leucine-rich repeats containing adenylate cyclase stimulating receptors. The unique posttranslational modification of the TSHR leads to the transformation of its monomeric form to the subunit structure where the subunits A and B are connected by disulphide bonds. This natural processing occurs with the release from the receptor of a short peptide C, and is followed by the release of the subunit A. Both monomeric and dimeric forms of the receptor are stimulated by TSH, so no clear functional significance of TSHR modifications have been found. We can speculated that the processing of TSHR with the release of its large fragments contributes to the development of autoimmune diseases and production anti-TSH receptor autoantibodies. The extrathyroidal manifestations of Graves disease may also be related to metastasis of the autoimmune reaction to extrathyroidal sites via the released A subunit. The TSHR processing may, to some extent, be connected to the hyperthyroidism since the release of the subunit A from the receptor augmented the adenylate cyclase activity in the absence of TSH. According to the recent model of receptors action the TSHR is in equilibrium between the inactive (closed) and active (opened) conformations. In opened conformation it can associate with Gs protein and trigger the intracellular signal. TSH and stimulating autoantibodies preferentially bind to opened receptors and stabilizes them.  相似文献   

18.
Type 2 diabetes (T2D) is characterized by impaired insulin secretion, insulin insensitivity and decreased beta-cell mass. Multiple genes contribute to T2D. The chromosome 12q13.1 region is in linkage to T2D in different populations, including our Italian dataset. CHOP is a candidate gene for the linkage, as it is located in the chromosome 12q13.1 region, and may contribute to T2D by increasing beta-cell apoptosis susceptibility and by impairing insulin sensitivity. Our goal was to identify any potential CHOP gene variants contributing to T2D in our Italian early-onset T2D families, which show linkage to the CHOP region. We directly sequenced the CHOP gene in 28 Italian probands of the linked T2D families and in 115 control subjects. We performed genotype and haplotype association tests with T2D of the identified single nucleotide polymorphisms (SNPs). We performed model-free and parametric association haplotype tests with T2D. We identified three SNPs [5'UTR-c.279T > C, 5'UTR-c.120A > G and + nt30C > T (F10F)] in CHOP. These SNPs are in complete linkage disequilibrium. The genotype association test showed an association trend with T2D of TT (F10F) and AG (-c.120A > G). The haplotype association test provided significant results for the haplotypes T/C (frequency = 0.33) and C/T (frequency = 0.01) (at 5'UTR-c.279T > C and + nt30C > T, respectively) under non-parametric analysis (P-value = 0.0000), recessive model (P-value = 0.0000) and additive model (P-value = 0.0014). Our data show that CHOP described haplotypes T/C and C/T, as an additive and as a homozygous variant, contribute significantly to T2D in our Italian early-onset group. We conclude that the CHOP T/C and C/T haplotype contributes to our T2D linkage signal on chromosome 12q13.1.  相似文献   

19.
The Collaboration for AIDS Vaccine Discovery/Comprehensive Antibody-Vaccine Immune Monitoring Consortium (CAVD/CA-VIMC) assisted an international network of laboratories in transferring a validated assay used to judge HIV-1 vaccine immunogenicity in compliance with Good Clinical Laboratory Practice (GCLP) with the goal of adding quality to the conduct of endpoint assays for Human Immunodeficiency Virus I (HIV-1) vaccine human clinical trials. Eight Regional Laboratories in the international setting (Regional Laboratories), many located in regions where the HIV-1 epidemic is most prominent, were selected to implement the standardized, GCLP-compliant Neutralizing Antibody Assay for HIV-1 in TZM-bl Cells (TZM-bl NAb Assay). Each laboratory was required to undergo initial training and implementation of the immunologic assay on-site and then perform partial assay re-validation, competency testing, and undergo formal external audits for GCLP compliance. Furthermore, using a newly established external proficiency testing program for the TZM-bl NAb Assay has allowed the Regional Laboratories to assess the comparability of assay results at their site with the results of neutralizing antibody assays performed around the world. As a result, several of the CAVD/CA-VIMC Regional Laboratories are now in the process of conducting or planning to conduct the GCLP-compliant TZM-bl NAb Assay as an indicator of vaccine immunogenicity for ongoing human clinical trials.  相似文献   

20.
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