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41.
Quaranta M Coviello M Daniele A Abbate I Durrant LG Paradiso A Schittulli F 《The International journal of biological markers》2004,19(2):109-114
Mucins are an important class of complex glycoproteins expressed by many epithelial cells and their malignant counterparts. The aim of this study was to determine the serum levels of MUC3 and mucin-like carcinoma-associated antigen (MCA) in patients with primary breast cancer and to analyze the possible relationships between these two mucins and the steroid receptor status. The preoperative basal serum levels of MUC3 (ELISA assay with monoclonal antibody 1143/B7) and MCA (EIA assay with anti-MCA mouse monoclonal antibody b-12) were determined in 44 patients with breast cancer while estrogen receptor (ER) and progesterone receptor (PgR) levels were measured by the dextran-coated charcoal method in the cytosol of neoplastic tissue. MUC3 was expressed in 43/44 serum samples while high MCA serum levels were found in 16/44 only; the mean values of both markers did not correlate with menopausal status, tumor size, nodal involvement or ER. The only significant difference observed was a lower median value of MCA in patients with small tumors (T1-T2). No statistically significant correlation between MUC3 and MCA, MUC3 and ER or MCA and ER was observed; a statistically significant direct correlation between MUC3 and PgR+ status and a statistically significant inverse correlation between MCA and PgR+ were observed. Our results suggest that further investigations are necessary to establish whether progesterone can modulate MUC3 and MCA expression in breast cancer. 相似文献
42.
2-Arachidonoylglycerol (2-AG) is a naturally occurring monoglyceride that activates cannabinoid receptors and meets several key requisites of an endogenous cannabinoid substance. It is present in the brain (where its levels are 170-folds higher than those of anandamide), is produced by neurons in an activity- and calcium-dependent manner, and is rapidly eliminated. The mechanism of 2-AG inactivation is not completely understood, but is thought to involve carrier-mediated transport into cells followed by enzymatic hydrolysis. We examined the possible role of the serine hydrolase, monoglyceride lipase (MGL), in brain 2-AG inactivation. We identified by homology screening a cDNA sequence encoding for a 303-amino acid protein, which conferred MGL activity upon transfection to COS-7 cells. Northern blot and in situ hybridization analyses revealed that MGL mRNA is unevenly present in the rat brain, with highest levels in regions where CB1 cannabinoid receptors are also expressed (hippocampus, cortex, anterior thalamus and cerebellum). Immunohistochemical studies in the hippocampus showed that MGL distribution has striking laminar specificity, suggesting a presynaptic localization of the enzyme. Adenovirus-mediated transfer of MGL cDNA into rat cortical neurons increased the degradation of endogenously produced 2-AG in these cells, whereas no such effect was observed on anandamide degradation. These results indicate that hydrolysis via MGL may be a primary route of 2-AG inactivation in intact neuronal cells. 相似文献
43.
Field ectomycorrhizae of Naucoria escharoides on Alnus acuminata ("andean alder", "aliso del cerro") are described in detail for the first time. Naturally occurring ectomycorrhizal roots were sampled beneath sporocarps of N. escharoides. The samples were taken from four natural forest plots at two homogeneous A. acuminata sites (Tucumán and Catamarca Provinces, Argentina). The ectomycorrhizae were characterized morphologically and compared by means of PCR/RFLP analysis of the internal transcribed spacer region of the nuclear rDNA. The most important morphological features of the ectomycorrhizae are a white to pale yellow mantle, simple to monopodial branches, hyaline emanating hyphae, abundant hyphal bundles emerging more or less perpendicularly from a plectenchymatous mantle, and an acute or rounded apex with or without a mantle. N. escharoides fruitbodies have white basal mycelium with emanating hyphae similar to those of andean alder ectomycorrhizae. The RFLP profiles of sporocarps and mycorrhizae were the same. 相似文献
44.
Replication and compartmentalization of HIV-1 in kidney epithelium of patients with HIV-associated nephropathy 总被引:11,自引:0,他引:11
Marras D Bruggeman LA Gao F Tanji N Mansukhani MM Cara A Ross MD Gusella GL Benson G D'Agati VD Hahn BH Klotman ME Klotman PE 《Nature medicine》2002,8(5):522-526
HIV-associated nephropathy is a clinicopathologic entity that includes proteinuria, focal segmental glomerulosclerosis often of the collapsing variant, and microcystic tubulointerstitial disease. Increasing evidence supports a role for HIV-1 infection of renal epithelium in the pathogenesis of HIV-associated nephropathy. Using in situ hybridization, we previously demonstrated HIV-1 gag and nef mRNA in renal epithelial cells of patients with HIV-associated nephropathy. Here, to investigate whether renal epithelial cells were productively infected by HIV-1, we examined renal tissue for the presence of HIV-1 DNA and mRNA by in situ hybridization and PCR, and we molecularly characterized the HIV-1 quasispecies in the renal compartment. Infected renal epithelial cells were removed by laser-capture microdissection from biopsies of two patients, DNA was extracted, and HIV-1 V3-loop or gp120-envelope sequences were amplified from individually dissected cells by nested PCR. Phylogenetic analysis of kidney-derived sequences as well as corresponding sequences from peripheral blood mononuclear cells of the same patients revealed evidence of tissue-specific viral evolution. In phylogenetic trees constructed from V3 and gp120 sequences, kidney-derived sequences formed tissue-specific subclusters within the radiation of blood mononuclear cell-derived viral sequences from both patients. These data, along with the detection of HIV-1-specific proviral DNA and mRNA in tubular epithelium cells, argue strongly for localized replication of HIV-1 in the kidney and the existence of a renal viral reservoir. 相似文献
45.
Conditionally immortalized cell lines as model systems for high-throughput biology in drug discovery
Daniele N Halse R Grinyo E Yeaman SJ Shepherd PR 《Biochemical Society transactions》2002,30(4):800-802
There is an increasing emphasis on the need for high-quality biological data much earlier in the drug-discovery process. This has led to the development of high-throughput approaches to biology, many of which rely on the use of cell-culture models. Unfortunately, available cell-culture models often reflect poorly the characteristics of the tissue they are supposed to represent. However, the conditional-immortalization approach as applied by Xcellsyz offers the possibility of producing human cell lines on demand, which are truly representative of the tissue from which they derive. 相似文献
46.
47.
Nature of polymorphisms in 16S-23S rRNA gene intergenic transcribed spacer fingerprinting of Bacillus and related genera 总被引:1,自引:0,他引:1
Daffonchio D Cherif A Brusetti L Rizzi A Mora D Boudabous A Borin S 《Applied and environmental microbiology》2003,69(9):5128-5137
The intergenic transcribed spacers (ITS) between the 16S and 23S rRNA genetic loci are frequently used in PCR fingerprinting to discriminate bacterial strains at the species and intraspecies levels. We investigated the molecular nature of polymorphisms in ITS-PCR fingerprinting of low-G+C-content spore-forming bacteria belonging to the genera Bacillus, Brevibacillus, Geobacillus, and Paenibacillus: We found that besides the polymorphisms in the homoduplex fragments amplified by PCR, heteroduplex products formed during PCR between amplicons from different ribosomal operons, with or without tRNA genes in the ITS, contribute to the interstrain variability in ITS-PCR fingerprinting patterns obtained in polyacrylamide-based gel matrices. The heteroduplex nature of the discriminating bands was demonstrated by fragment separation in denaturing polyacrylamide gels, by capillary electrophoresis, and by cloning, sequencing, and recombination of purified short and tRNA gene-containing long ITS. We also found that heteroduplex product formation is enhanced by increasing the number of PCR cycles. Homoduplex-heteroduplex polymorphisms (HHP) in a conserved region, such as the 16S and 23S rRNA gene ITS, allowed discrimination of closely related strains and species undistinguishable by other methods, indicating that ITS-HHP analysis is an easy and reproducible additional tool for strain typing. 相似文献
48.
Background
A large body of data derived from animal, epidemiological and clinical studies indicate that n-3 polyunsaturated fatty acids have a favourable effect on the prognosis of patients with cardiovascular disease in general, and on reducing sudden death in particular. Depressed heart rate variability (HRV), an indicator of impairment of the autonomic nervous system, has been shown to be a powerful predictor of subsequent mortality in patients surviving an acute myocardial infarction. A multitude of studies have demonstrated this strong association, suggesting that the imbalance in the sympathic/parasympathetic system may facilitate emergence of ventricular arrhythmias. Heart rate variability parameters will be assessed in the present study, with the primary objective of evaluating the possible superiority of Omacor (a highly refined, concentrated omega-3 fatty acid) versus placebo in improving HRV from baseline to endpoint in patients with recent uncomplicated myocardial infarction. Both groups will receive optimal conventional treatment. The study will also explore and quantify improvement in time domain HRV indices and will assess the safety of administering Omacor to optimally treated post-infarction patients (conventional treatment).Methods
This multi-centre study will evaluate the effect of Omacor 1 g, o.d. on time-domain HRV parameters in comparison to placebo o.d. in patients with recent uncomplicated transmural myocardial infarction. Patients will be screened during the first few days after the acute event as appropriate for the patient's condition, and after obtaining informed consent. Based on inclusion/exclusion criteria, a first 24-hour Holter recording will be performed. Two to five days later, screened patients still eligible for the study will undergo a second 24-hour Holter recording. After the second Holter recording, all patients will be randomly allocated to treatment with Omacor 1 g, o.d. or placebo o.d. One hundred patients will be followed in double-blind fashion for a six-month period after randomization. Visits, including 24-hour Holter recording and assessment of adverse events, will take place at one-month intervals ± five days after randomization, i.e., six times in all. 相似文献49.
Daniele?ArobbaEmail author Rosanna?Caramiello Angiolo?Del Lucchese 《Vegetation History and Archaeobotany》2003,12(4):253-262
The archaeological site we studied is part of an early Iron Age hill fort (8th/7th cent. b.c.), located 800 m from the coast on the top of a hill named MonteTrabocchetto. This paper concerns an excavation, called saggio O, which disclosed a very varied stratigraphy characterised by highly anthropogenic layers and by a pit, presumably used as a silo for food storage, which was very rich in charred seeds and fruits. The study of the pit content showed the dominance of Hordeum vulgare, while Triticum dicoccon, T. monococcum, T. aestivum/durum, Panicum miliaceum and Setaria italica were less strongly represented. Some edible Leguminosae were also found (Lens culinaris, Vicia faba var. minor and V. ervilia). In the frequented areas around the pit, herbaceous weeds and fruit tree macro-remains were present (Prunus cf. spinosa, Corylus avellana, Quercus sp. and Vitis vinifera ssp. sylvestris). The identification of a large number of botanical taxa has provided important information on food of plant origin and agricultural practices during the early Iron Age on the Ligurian coast, the proto-historic archaeobotanical aspects of which are largely unknown. 相似文献
50.
Di Fabio R Tranquillini E Bertani B Alvaro G Micheli F Sabbatini F Pizzi MD Pentassuglia G Pasquarello A Messeri T Donati D Ratti E Arban R Dal Forno G Reggiani A Barnaby RJ 《Bioorganic & medicinal chemistry letters》2003,13(21):3863-3866
To identify neuroprotective agents after stroke, new substituted tetrahydroquinoline derivatives were designed as antagonists of the glycine binding site associated to the NMDA receptor, satisfying the key pharmacophoric requirements. In particular, the racemate 3c exhibited outstanding in vivo activity in the MCAo model in rats, when given iv both pre- and post-ischemia. Pure enantiomers 3c-(+) and 3c-(-) have been prepared following an original synthetic route. Despite the significant difference of activity observed in vitro, they shown similar neuroprotective profile in the MCAo model in rats. 相似文献