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1.
The use of directional coronary atherectomy (DCA) in current practice has been limited. The SilverHawk System is a newly developed plaque excision device that aims to overcome the drawbacks of prior DCA platforms. The device was evaluated in a porcine coronary model and in a series of patients. Procedural variables along with outcomes were reviewed. Quantitative angiography (QCA) was performed and excised tissue fragments were weighed and examined histologically. In porcine cases, pretreatment MLD increased from 0.51 +/- 0.26 to 2.36 +/- 0.59 mm postdebulking and 19.9 +/- 7.6 mg of tissue was retrieved. In human cases, pretreatment MLD increased from 0.8 +/- 0.4 to 2.2 +/- 0.5 mm postdebulking and 15.2 +/- 7.8 mg of tissue was retrieved without complications. These data show that the SilverHawk System may offer significant utility in treating a wide variety of complex coronary lesions.  相似文献   
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Altered adhesion plaques have been observed in transformed cell lines and are associated with enhanced metastatic potential. The prototypical adhesion plaque is formed by 51 fibronectin receptors (FnRs) interacting with the cellular actin network. We have found differences in the actin networks of noninvasive (FTC-133) and invasive (FTC-236, FTC-238) clones of a human follicular thyroid cancer cell line. Furthermore, thyroid-stimulating hormone (TSH) induces stress fibers in FTC-133. In order to investigate differences in adhesion plaques, expression of fibronectin (FN) and its receptor by these cells was analyzed. For these studies FTC-133, FTC-236, and FTC-238 were cultured in serum-depleted DME-H21 medium for 24 hours before the addition of TSH 30 mU/ml. No quantitative differences were noted in FN expression on Western blot in either the conditioned medium or cellular extracts. Western blots and immunohistochemical studies indicated that TSH induced secretion of FN only in FTC-133. Flow cytometry with an 5 antibody demonstrated a 52% and 45% reduction (p<0.01) in expression of FnR by FTC-236 and FTC-238, respectively, compared to FTC-133; this finding was supported by immunohistochemistry results. TSH treatment did not alter FnR expression. From these studies, we conclude that invasive clones of FTC decrease their expression of FnRs without changing their expression of FN. Furthermore, TSH treatment may promote FN secretion by FTC-133, although it does not seem to affect FnR or absolute FN expression. The diminished expression of FnR adhesion plaques may enhance metastatic potential in some follicular thyroid cancers.
Resumen Se han observado placas adhesivas alteradas en líneas celulares transformadas en asociación con un potencial metastásico incrementado. La prototípica placa adhesiva se forma por la interacción de receptores 5-1 con la trama celular de actina. Hemos encontrado diferencias en las tramas de actina en clones no invasivos (FTC-133) e invasivos (FTC-236, FTC-238) de una línea celular de cáncer folicular de tiroides.Además, la TSH induce líneas de estrés en FTC-133. Con el objeto de investigar las diferencias en las placas adhesivas, se hizo el análisis de la expresión de fibronectina (FN) y sus receptores en tales células.Para estos estudios se hizo el cultivo de FTC-133, FTC-236 y FTC-238, en sueros depletados de DME-H21 por 24 horas anteriores a la adición de 30 mU/ml TSH por 24 horas. No se observaron diferencias cuantitativas en la expresion de FN o en el Western blot ni en los medios condicionados ni en los extractos celulares. Los Western blots y los estudios inmunohistoquímicos indicaron que la TSH induce la secreción de FN sólo en FTC-133. La citometría de flujo con un anticuerpo 5 demostró una reducción de 52% y 45% (p<0.01) en la expresión de FnR por FTC-236 y FT-238, respectivamente, en comparación con FTC-133; este hallazgo fue verificado por inmuno-histoquímica. El tratamiento con TSH no alteró la expresón FnR. Con base en estos estudios, es nuestra conclusión que los clones invasivos de FTC disminuyen la expresión de FnR sin cambiar su expresión de FN. Además, el tratamiento con TSH puede promover la secreciòn de FN por FTC-133, aunque no parece afectar la expresión de FnR o la expresión absoluta de FN. Esta expresión disminuída de las placas adhesivas FnR puede incrementar el potencial metastásico en algunos cánceres foliculares de tiroides.

Résumé On a observé des altérations des plaques d'adhésion dans certaines lignées cellulaires transformées, et celles-ci semblent être associées à un potentiel métastatique augmenté. La plaque d'adhésion prototypique est formée par des récepteurs 51 de fibronectine (FnR) qui agissent sur le réseau cellulaire d'actine. Nous avons trouvé une différence entre les réseaux d'actine des clones noninvasifs (FTC-133) et invasifs (FTC-236, FTC-238) des lignées cellulaires dans le cancer folliculaire de la thyroïde chez l'homme. La TSH induit des fibres de stress dans le FTC-133. Afin d'évaluer les différences dans les plaques d'adhésion, l'expression de la fibronectine (FN) et de son récepteur ont été analysées. Pour ces études, les clones FTC-133, FTC-236 et FTC-238 ont été mis en culture dans le milieu DME-H21 dépourvu en sérum pendant 24 heures avant l'addition de 30 mU/ml de TSH/24 heures. II n'y avait aucune différence quantitative dans l'expression FN sur Western blot que ce soit sur le milieu ainsi conditionné ou sur les extraits cellulaires. Les Western blots et les études immunohistochimiques ont indiqué que la TSH n'induisait la sécrétion de FN que dans la lignée FTC-133. La cytométrie de flux avec l'anticorps 5 a démontré une réduction respectivement de 52% et de 45% (p<0.01) dans l'expression de FnR par les clones FTC-236 et FTC-238, comparé au FTC-133. Cette donnée a été confirmée par l'immunohistochimie. A partir de ces études, nous concluons que les clones d'invasion de FTC diminuent leur expression en FnR sans changer leur expression de FN. De plus, un traitement par la TSH peut induire la sécrétion de FN par le clone FTC-133 alors qu'il ne semble pas influencer le FnR ou l'expression FN. L'expression diminuée des plaques d'adhésion FnR semble potentialiser les métastases dans certains cancers de la thyroïde.
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Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. In this study, adenosine triphosphate (ATP) and flow cytometry (FCM) were employed to monitor the performance of the micro-aerobic process and investigate the survival of bacterial cells within the process. At first, the effect of air flow rate (AFR) (0.1, 0.2, 0.3 and 0.5 vvm) on hydrolysis of mixed sludge in 5 aeration cycles (20, 30, 40, 48 and 60 hours) was examined. Then, the effects of the micro aerobic process on methane (CH4) production in anaerobic digestion were surveyed. The highest VSS reduction was 30.6% and 10.4% for 40 hours in the reactor and control, respectively. Soluble COD also fluctuated between 40.87 and 65.14% in micro-aerobic conditions; the highest SCOD was achieved at the time of 40 h. Microbial activities were increased by 597%, 170% and 79.4% for 20, 30 and 40 h pretreatment with the micro-aerobic process, respectively. Apoptosis assay showed that micro-aerobic pre-treatment at 20, 30 and 40 h increased the percentage of living cells by 57.4, 62.8 and 67.9%, respectively. On the other hand, FCM results showed that the highest percentage of viable bacteria (i.e., 67.9%) was observed at 40 h pretreating which was approximately 40% higher the ones for the control. Variation in cumulative methane production shows that methane production was increased by 221% compared to anaerobic digestion (control group). Therefore, ATP and FCM can be employed as two appropriate, accurate, relatively specific indicators for monitoring the process and bacteria viability.

Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production.  相似文献   
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Background:

Occult hepatitis C virus infection (OCI) is recognized by finding hepatitis C virus (HCV) RNA in hepatocytes without detectable anti-HCV antibodies and viral RNA in plasma. Autoimmune hepatitis (AIH) is a chronic and generally progressive disease without exactly-identified etiology.

Objectives:

This study aimed to determine the prevalence of OCI among patients with AIH and to evaluate the tests used to rule out HCV infection in diagnosing AIH.

Patients and Methods:

Between July 2012 to February 2013, 35 Iranian patients with AIH who attended Tehran Hepatitis Center were investigated. For identifying OCI, detection of HCV RNA in both ultracentrifuged serum samples and peripheral blood mononuclear cells (PBMCs) was used. Data analysis was performed using SPSS.

Results:

Six males and 29 females with mean disease duration of 77.1 ± 39.5 month and mean age of 43.62 ± 12.67 years were investigated. All cases were negative for anti-HCV antibody and we could not find any HCV RNA in ultracentrifuged serum samples and PBMCs.

Conclusions:

With our laboratory diagnostic method, it seems that there are no cases of OCI in patients with AIH. However, we recommend further studies with more samples and more precise laboratory method.  相似文献   
8.
A 3-year-old female Holstein cow was referred for necropsy examination with the history of inappetence, progressive indigestion, distension of the rumen and death. At necropsy examination, a lobulated grey-white mass (12?×?8?×?5 cm) was found close to the reticulo-omasal orifice. On sectioning, the tumour mass was gelatinous with intervening fibrous septa. Microscopical examination revealed unencapsulated mass composed of various cellular parts and matrices. There were proliferated spindle shaped fibrocytes producing repetitive collagenous fibres. There were also foci of low cellularity containing stellate cells with small and hyperchromatic nuclei arranged in a mucinous ground substance. On the basis of the gross and histopathological findings and histochemical stainings, the tumour was diagnosed as a fibromyxoma. This tumour has not been recorded previously in the reticulo-omasal orifice of a cow.  相似文献   
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Soluble epoxide hydrolase (sEH) inhibitors are effective in reducing blood pressure, inflammation, and pain in a number of mammalian disease models. As most classical urea-based sEH inhibitors suffer from poor solubility and pharmacokinetic properties, the development of novel sEH inhibitors with an improved pharmacokinetic specification has received a great deal of attention. In this study, a series of amide-based sEH inhibitors bearing a phthalimide ring as the novel secondary pharmacophore (P2) was designed, synthesized, and evaluated. Docking results illustrated that the amide group as the primary pharmacophore (P1) was placed at a suitable distance from the three key amino acids (Tyr383, Tyr466, and Asp335) for an effective hydrogen bonding. In agreement with these findings, most of the newly synthesized compounds demonstrated moderate to high sEH inhibitory activities, relative to 12-(3-adamantan-1-yl-ureido)dodecanoic acid as the reference standard. Compound 12e with a 4-methoxybenzoyl substituent exhibited the highest sEH inhibitory activity, with an IC50 value of 1.06 nM. Moreover, the ADME properties of the compounds were evaluated in silico, and the results revealed appropriate predictions.  相似文献   
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