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1.
CD97, but not its closely related EGF-TM7 family member EMR2, is expressed on gastric,pancreatic, and esophageal carcinomas 总被引:2,自引:0,他引:2
Aust G Steinert M Schütz A Boltze C Wahlbuhl M Hamann J Wobus M 《American journal of clinical pathology》2002,118(5):699-707
CD97 expression is related closely to the dedifferentiation and tumor stage in thyroid carcinomas. We systematically examined the role of CD97 and its closest relative, EMR2, in normal and malignant gastric, esophageal, and pancreatic tissue. The normal tissues were EMR2-, whereas CD97 was expressed slightly in the parietal cells of gastric mucosa and in exocrine pancreatic cells. Interestingly, intralobular and interlobular pancreatic ducts were CD97+. All tumors were EMR2-. CD97 was expressed by 44 of 50 gastric, 14 of 18 pancreatic, and 10 of 13 esophageal carcinomas. Of the 44 gastric cancers, 27 showed disseminated or scattered tumor cells at the invasion front with stronger CD97 expression than tumor cells located in solid tumor formations. There was no correlation between CD97 levels in the tumors or soluble CD97 in the serum samples and the clinicopathologic features of the patients. Taken together, significant numbers of gastric, esophageal, and pancreatic carcinomas are CD97+, whereas its homolog, EMR2, does not have any role in such tumors. 相似文献
2.
Role of the Salmonella pathogenicity island 1 effector proteins SipA, SopB, SopE, and SopE2 in Salmonella enterica subspecies 1 serovar Typhimurium colitis in streptomycin-pretreated mice
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Hapfelmeier S Ehrbar K Stecher B Barthel M Kremer M Hardt WD 《Infection and immunity》2004,72(2):795-809
Salmonella enterica subspecies 1 serovar Typhimurium (serovar Typhimurium) induces enterocolitis in humans and cattle. The mechanisms of enteric salmonellosis have been studied most extensively in calf infection models. The previous studies established that effector protein translocation into host cells via the Salmonella pathogenicity island 1 (SPI-1) type III secretion system (TTSS) is of central importance in serovar Typhimurium enterocolitis. We recently found that orally streptomycin-pretreated mice provide an alternative model for serovar Typhimurium colitis. In this model the SPI-1 TTSS also plays a key role in the elicitation of intestinal inflammation. However, whether intestinal inflammation in calves and intestinal inflammation in streptomycin-pretreated mice are induced by the same SPI-1 effector proteins is still unclear. Therefore, we analyzed the role of the SPI-1 effector proteins SopB/SigD, SopE, SopE2, and SipA/SspA in elicitation of intestinal inflammation in the murine model. We found that sipA, sopE, and, to a lesser degree, sopE2 contribute to murine colitis, but we could not assign an inflammation phenotype to sopB. These findings are in line with previous studies performed with orally infected calves. Extending these observations, we demonstrated that in addition to SipA, SopE and SopE2 can induce intestinal inflammation independent of each other and in the absence of SopB. In conclusion, our data corroborate the finding that streptomycin-pretreated mice provide a useful model for studying the molecular mechanisms of serovar Typhimurium colitis and are an important starting point for analysis of the molecular events triggered by SopE, SopE2, and SipA in vivo. 相似文献
3.
Manja M. Zec Irena Krga Ljiljana Stojkovi Maja
ivkovi Biljana Pokimica Aleksandra Stankovi Maria Glibetic 《Nutrients》2021,13(2)
Dietary polyphenols promote cardiometabolic health and are linked with long-chain polyunsaturated fatty acids in plasma phospholipids (LC-PUFA). The FADS2 polymorphisms are associated with LC-PUFA metabolism and overweight/obesity. This 4-week study examined the link between polyphenol intake, FADS2 variants (rs174593, rs174616, rs174576) and obesity in 62 overweight adults (BMI ≥ 25), allocated to consume 100 mL daily of either: Aronia juice, a rich source of polyphenols, with 1177.11 mg polyphenols (expressed as gallic acid equivalents)/100 mL (AJ, n = 22), Aronia juice with 294.28 mg polyphenols/100 mL (MJ, n = 20), or nutritionally matched polyphenol-lacking placebo as a control (PLB, n = 20). We analyzed LC-PUFA (% of total pool) by gas chromatography and FADS2 variants by real-time PCR. Four-week changes in LC-PUFA, BMI, and body weight were included in statistical models, controlling for gender and PUFA intake. Only upon AJ and MJ, the presence of FADS2 variant alleles affected changes in linoleic, arachidonic, and eicosapentaenoic acid (EPA). Upon MJ treatment, changes in EPA were inversely linked with changes in BMI (β= −0.73, p = 0.029) and weight gain (β= −2.17, p = 0.024). Only in subjects drinking AJ, the link between changes in EPA and anthropometric indices was modified by the rs174576 variant allele. Our results indicate the interaction between FADS2, fatty acid metabolism, and polyphenol intake in overweight subjects. 相似文献
4.
5.
Estimation of circulatory parameters in patients with acute myocardial infarction. Significance for calculation of enzymatic infarct size 总被引:5,自引:0,他引:5
Estimation of infarct size from enzyme activities in plasma or serum presupposes known values of circulatory parameters such as the extravascular distribution volume Ve and the permeability constant P for the transport of enzyme between intravascular volume Vi and Ve. In man, parameter values are used that are extrapolated either from values found in the dog or from turnover studies of non-myocardial proteins. Large systematic errors can be introduced in this way, as demonstrated in this study. It is shown that by simultaneous determination of two different enzymes in the same patient, estimates of circulatory parameters are obtained. The method is applied to creatine kinase (CK) and alpha-hydroxybutyrate dehydrogenase (HBDH) plasma activities in 36 patients with acute myocardial infarction (AMI). The following results are obtained: 1. Exchange of enzyme between Vi and Ve is much slower and clearance of CK is much faster than presently assumed in the literature. 2. Release of CK and HBDH into the circulation is proportional to the amounts of these enzymes present in the myocardium. This finding is supported by data on early enzyme release. 3. Quantitation of HBDH release needs a two-compartment model, while for CK a one-compartment model can be used in good approximation. 4. Release of CK and HBDH after AMI continues up to 96 hours. 5. Using obtained parameter values, a simulated model demonstrates that estimation of clearance rates of CK from exponential fits on plasma levels results in large errors. This may explain recent conflicting results in validation of enzymatic estimates of infarct size. 相似文献
6.
Caspar Grond-Ginsbach Tiina M. Metso Antti J. Metso Alessandro Pezzini Turgut Tatlisumak Maani Hakimi Armin J. Grau Manja Kloss Christoph Lichy 《Medical hypotheses》2013
Cervical artery dissection (CeAD) is a frequent cause of stroke among young patients. It is unclear how many CeADs occur asymptomatically or cause subtle and unspecific clinical symptoms. We hypothesize that CeAD remains often unrecognized. Accordingly, the incidence of CeAD might be higher and the stroke risk lower than generally assumed. Lack of CeAD-indicating clinical symptoms is regarded as the main cause of missed diagnoses. We further hypothesize that underrepresentation of asymptomatic and oligosymptomatic patients in CeAD studies may have biased the association between ischemia and local symptoms in CeAD patients as well as the associations of CeAD with risk factors or co-morbidities. We finally hypothesize that symptomatic CeAD may be preceded by an initial asymptomatic phase. According to this final hypothesis, the time of onset of CeAD should be considered uncertain. The issue of unrecognized CeAD is relevant, as it may affect the associations between CeAD and putative risk factors. Furthermore, the existence of clinically silent CeADs may explain why recurrent and familial CeAD have been rarely observed. 相似文献
7.
8.
Co(II)‐mediated effects of plain and plasma immersion ion implanted cobalt‐chromium alloys on the osteogenic differentiation of human mesenchymal stem cells
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9.
Mattia Quattrocelli Melissa Swinnen Giorgia Giacomazzi Jordi Camps Ines Barthélemy Gabriele Ceccarelli Ellen Caluwé Hanne Grosemans Lieven Thorrez Gloria Pelizzo Manja Muijtjens Catherine M. Verfaillie Stephane Blot Stefan Janssens Maurilio Sampaolesi 《The Journal of clinical investigation》2015,125(12):4463-4482
Conditions such as muscular dystrophies (MDs) that affect both cardiac and skeletal muscles would benefit from therapeutic strategies that enable regeneration of both of these striated muscle types. Protocols have been developed to promote induced pluripotent stem cells (iPSCs) to differentiate toward cardiac or skeletal muscle; however, there are currently no strategies to simultaneously target both muscle types. Tissues exhibit specific epigenetic alterations; therefore, source-related lineage biases have the potential to improve iPSC-driven multilineage differentiation. Here, we determined that differential myogenic propensity influences the commitment of isogenic iPSCs and a specifically isolated pool of mesodermal iPSC-derived progenitors (MiPs) toward the striated muscle lineages. Differential myogenic propensity did not influence pluripotency, but did selectively enhance chimerism of MiP-derived tissue in both fetal and adult skeletal muscle. When injected into dystrophic mice, MiPs engrafted and repaired both skeletal and cardiac muscle, reducing functional defects. Similarly, engraftment into dystrophic mice of canine MiPs from dystrophic dogs that had undergone TALEN-mediated correction of the MD-associated mutation also resulted in functional striatal muscle regeneration. Moreover, human MiPs exhibited the same capacity for the dual differentiation observed in murine and canine MiPs. The findings of this study suggest that MiPs should be further explored for combined therapy of cardiac and skeletal muscles. 相似文献
10.
Heindl M Händel N Ngeow J Kionke J Wittekind C Kamprad M Rensing-Ehl A Ehl S Reifenberger J Loddenkemper C Maul J Hoffmeister A Aretz S Kiess W Eng C Uhlig HH 《Gastroenterology》2012,142(5):1093-1096.e6
The Phosphatase And Tensin Homolog Deleted On Chromosome 10 (PTEN) regulates the phosphoinositol-3-kinase (PI3K)-AKT signaling pathway. In a series of 34 patients with PTEN mutations, we described gastrointestinal lymphoid hyperplasia, extensive hyperplastic tonsils, thymus hyperplasia, autoimmune lymphocytic thyroiditis, autoimmune hemolytic anemia, and colitis. Functional analysis of the gastrointestinal mucosa-associated lymphoid tissue revealed increased signaling via the PI3K-AKT pathway, including phosphorylation of S6 and increased cell proliferation, but also reduced apoptosis of CD20(+)CD10(+) B cells. Reduced activity of PTEN therefore affects homeostasis of human germinal center B cells by increasing PI3K-AKT signaling via mammalian target of rapamycin as well as antiapoptotic signals. 相似文献