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991.
992.
We investigated whether residual material from diagnostic smears of fine needle aspirations (FNAs) of mammographically detected breast lesions can be successfully used to extract RNA for reliable gene expression analysis. Twenty-eight patients underwent FNA of breast lesions under ultrasonographic guidance. After smearing slides for cytology, residual cells were rinsed with TRIzol to recover RNA. RNA yield ranged from 0.78 to 88.40 μg per sample. FNA leftovers from 23 nonpalpable breast cancers were selected for gene expression profiling using oligonucleotide microarrays. Clusters generated by global expression profiles partitioned samples in well-distinguished subgroups that overlapped with clusters obtained using "biologic scores" (cytohistologic variables) and differed from clusters based on "technical scores" (RNA/complementary RNA/microarray quality). Microarray profiling used to measure the grade of differentiation and estrogen receptor and ERBB2/HER2 status reflected the results obtained by histology and immunohistochemistry. Given that proliferative status in the FNA material is not always assessable, we designed and performed on FNA leftover a multiprobe genomic signature for proliferation genes that strongly correlated with the Ki67 index examined on histologic material. These findings show that cells residual to cytologic smears of FNA are suitable for obtaining high-quality RNA for high-throughput analysis even when taken from small nonpalpable breast lesions.  相似文献   
993.
Caloric restriction (CR) has been associated with health benefits and these effects have been attributed, in part, to modulation of oxidative status by CR; however, data are still controversial. Here, we investigate the effects of seventeen weeks of chronic CR on parameters of oxidative damage/modification of proteins and on antioxidant enzyme activities in cardiac and kidney tissues. Our results demonstrate that CR induced an increase in protein carbonylation in the heart without changing the content of sulfhydryl groups or the activities of superoxide dismutase and catalase (CAT). Moreover, CR caused an increase in CAT activity in kidney, without changing other parameters. Protein carbonylation has been associated with oxidative damage and functional impairment; however, we cannot exclude the possibility that, under our conditions, this alteration indicates a different functional meaning in the heart tissue. In addition, we reinforce the idea that CR can increase CAT activity in the kidney. [BMB Reports 2012; 45(11): 671-676]  相似文献   
994.
Adjusting translation is crucial for cells to rapidly adapt to changing conditions. While pro-proliferative signaling via the PI3K-mTOR-pathway is known to induce cap-dependent translation, stress conditions, such as nutrient deprivation or hypoxia often activate alternative modes of translation, e.g., via internal ribosome entry sites (IRESs). As the effects of inflammatory conditions on translation are only poorly characterized, we aimed at identifying translationally deregulated targets in inflammatory settings. For this purpose, we cocultured breast tumor cells with conditioned medium of activated monocyte-derived macrophages (CM). Polysome profiling and microarray analysis identified early growth response-2 (egr2) to be regulated at the level of translation. Using bicistronic reporter assays, we found that egr2 contains an IRES within its 5′ UTR, which facilitated enhanced translation upon CM treatment. We further provide evidence that the activity of egr2-IRES was induced by IL-1β and p38-MAPK signaling. In addition, we identified several potential IRES trans-acting factors (ITAFs) such as polypyrimidine tract binding protein (PTB) and hnRNP-A1 that directly bind to the egr2-5′UTR. In summary, our data provide evidence that egr2 expression is translationally regulated via an IRES element, which is responsive to an inflammatory environment.  相似文献   
995.
α-l-Rhamnosidase (EC 3.2.1.40) is a biotechnologically important enzyme used for derhamnosylation of many natural compounds. The extracellular α-l-rhamnosidase was purified from the culture of Aspergillus terreus grown on l-rhamnose-rich medium. This enzyme was found to be thermo- and alkali-tolerant, able to operate at 70 °C and pH 8.0. The α-l-rhamnosidase cDNA was cloned from A. terreus, sequenced, and expressed in the yeast Pichia pastoris as a fully functional protein. The recombinant protein was purified to apparent homogeneity and biochemically characterized. Both the native and the recombinant α-l-rhamnosidases catalyzed the conversion of rutin into quercetin-3-glucopyranoside (isoquercitrin), a pharmacologically significant flavonoid usable in nutraceutics. This procedure has high volumetric productivity (up to 300 g/L) and yields the product void of unwanted quercetin. The significant advantage of our expression system consists in shorter production times, up to fourfold increase in enzyme yields and the absence of unwanted β-d-glucosidase as compared to the native production system. Thanks to its unique properties, this enzyme is applicable in a selective synthesis/hydrolysis of various rhamnose containing structures.  相似文献   
996.
In all European countries, the eighteenth century was characterised by efforts to improve the vernaculars. The Transylvanian case study shows how both codified medical language and ordinary language were constructed and enriched by a large number of medical books and brochures. The publication of medical literature in Central European vernacular languages in order to popularise new medical knowledge was a comprehensive programme, designed on the one hand by intellectual, political and religious elites who urged the improvement of the fatherland and the promotion of the common good by perfecting the arts and sciences. On the other hand, the imperial administration's initiatives affected local forms of medical knowledge and the construction of vernacular languages. In the eighteenth century, the construction of vernacular languages in the Habsburg Monarchy took on a significant political character. However, in the process of building of the scientific and medical vocabulary, the main preoccupation was precision, clarity and accessibility of the neologisms being invented to encompass the medical phenomena being described. In spite of political conflicts among the 'nations' living in Transylvania, physicians borrowed words from German, Hungarian and Romanian. Thus they elevated several words used in everyday language to the upper social stratum of language use, leading to the invention of new terms to describe particular medical practices or phenomena.  相似文献   
997.
Trypanosoma cruzi infection triggers a chronic inflammatory process in human host and purinergic system ecto-enzymes play an important role in modulating the inflammatory and immune responses. In this study, it was investigated ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase; EC 3.6.1.5; CD39) and ecto-adenosine deaminase (E-ADA; EC 3.5.4.4) activities in lymphocytes from patients with indeterminate form of Chagas' disease (IFCD). Twenty-five IFCD patients and 25 healthy subjects (control group) were selected. The peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Adenine nucleotides and adenosine levels were determined in serum by HPLC and the E-NTPDase1 expression in lymphocytes by Western blot analysis. E-NTPDase (ATP and ADP as substrates) and E-ADA (adenosine as substrate) activities were decreased in lymphocytes from IFCD patients (P<0.05 and P<0.01, respectively), while the E-NTPDase1 expression presented no changes in these patients. Serum ATP levels showed to be decreased (P<0.05) and both AMP (P<0.01) and adenosine (P<0.001) levels were increased in the IFCD group. The enzymatic alterations observed are in agreement with the immune response against T. cruzi infection in IFCD patients, since the decreased extracellular ATP and the increased adenosine levels trigger a Th2 anti-inflammatory response, which it is associated to adaptation of host to parasite, preventing clinical progress of disease.  相似文献   
998.
The proper balance of parental genomic contributions to the fertilized embryo and endosperm is essential for their normal growth and development. The characterization of many gametophytic maternal effect (GME) mutants affecting seed development indicates that there are certain classes of genes with a predominant maternal contribution. We present a detailed analysis of the GME mutant zak ixik (zix), which displays delayed and arrested growth at the earliest stages of embryo and endosperm development. ZIX encodes an Armadillo repeat (Arm) protein highly conserved across eukaryotes. Expression studies revealed that ZIX manifests a GME through preferential maternal expression in the early embryo and endosperm. This parent-of-origin–dependent expression is regulated by neither the histone and DNA methylation nor the DNA demethylation pathways known to regulate some other GME mutants. The ZIX protein is localized in the cytoplasm and nucleus of cells in reproductive tissues and actively dividing root zones. The maternal ZIX allele is required for the maternal expression of MINISEED3. Collectively, our results reveal a reproductive function of plant Arm proteins in promoting early seed growth, which is achieved through a distinct GME of ZIX that involves mechanisms for maternal allele-specific expression that are independent of the well-established pathways.  相似文献   
999.
3-Nitrotyrosine (3NT) is known as an important indicator of nitrosative stress and has been linked to various diseases. Our aim was to develop an indirect ELISA (enzyme-linked immunosorbent assay) method suitable for the detection of protein-bound 3NT in clinical plasma and serum samples. Nitrated protein standards and reduced protein standards were prepared. Limit of detection was determined for standards; recovery and reproducibility were determined for human plasma samples. The limit of detection for this method is 1.82±0.56 pmol/mg protein. Mean recovery of standards was 95%. 3NT concentration in plasma samples of obese and normal weight subjects was determined to be between 2 pmol/mg and 19 pmol/mg. No time-consuming sample preparation or expensive laboratory equipment is required, and applied antibodies are commercially available. Sensitivity, rapid analysis time, possibilities of high throughput applications and small sample volumes make this ELISA attractive for use in clinical laboratories.  相似文献   
1000.
The EE subunit of horse liver alcohol dehydrogenase (HLADH-EE) has been subcloned in pRSETb vector to generate a fusion His-tag protein. The migration from a multistep purification protocol for this well-known enzyme to a single-step has been successfully achieved. Several adjustments to the traditional purification procedure for His-tag proteins have been made to retain protein activity. A full characterization of the fusion enzyme has been carried out and compared with the native one. The K m for EtOH, NAD and NADH in the His-tag version of HLADH are in line with the ones reported in literature for the native enzyme. A shift in optimal pH activity is also observed. The enzyme retains the same stability and quaternary structure as the wild type and can therefore be easily used instead of the native HLADH for biotechnological applications.  相似文献   
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