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Colorectal cancer (CRC) is the second most frequent and fatal cancer in Western countries. Understanding its biology with different incidence along the colon and rectum, genetic profile and how these factors contribute to local/distant progression, has been hampered by the lack of a suitable CRC model.We report a reproducible model, using human CRC cell lines (CL) (WiDr, LS1034, C2BBe1) injected (1?×?107 cells/animal) in RNU rats (n?=?55) which underwent cecostomy and descending colostomy with mucosal-cutaneous fistula of the sigmoid colon. CL were characterized by immunohistochemistry: CK20, CDX2, P53, vimentin, Ki67, CD44, CD133, E-cadherin, β-catenin and CEA; cancer stem cells-immune system interaction was studied and tumor progression was assessed with nuclear medicine imaging (99mTc-MIBI).Animals developed locally invasive tumors and with WiDr neural invasion was registered. Cancer stem cells were detected in WiDr (CD44 positive). All the cell lines stimulated the immune system, being WiDr the most aggressive. Imaging studies demonstrated tumor uptake.With this CRC model we can study the microenvironment role and tumor-stroma interactions. All CL developed primary disease, but only the WiDR established neural invasion which may represent a metastatic pathway. This model can help unveiling the underlying metastatic mechanisms, and ultimately test better therapeutic approaches for CRC.  相似文献   
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Three Pseudomonas putida strains containing blaVIM-2 were isolated from an inanimate surface of a female ward sanitary facility in the Hospital Infante D. Pedro, Aveiro. A novel class 1 integron was found in strain Pp2 (aacA41blaVIM-2/aac6'-IIc disrupted by an insertion sequence IS1382), and strain PpI was found to carry a class 1 integron (aacA7/blaVIM-2/aacCl/aacA4), which is described for the first time in this species. Strain PFI carries a class 1 integron associated with a Tn5090-like transposon, constituting the first finding of this type of arrangement in a strain from Portugal. This association highlights further dissemination of blaVIM-2 in environmental hospital isolates.  相似文献   
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Throat packs are commonly used in maxillofacial surgeries. However, the evidence to support the benefits of their use is controversial. The aim of this study was to evaluate the effectiveness of throat packs in preventing postoperative nausea and vomiting, and their influence on the incidence of sore throat and dysphagia in patients undergoing orthognathic surgery. This was a prospective double-blind randomized study with 54 patients, who were randomized to two groups: with throat pack (n = 27) and without throat pack (n = 27). Fifty patients (25 in each group) were included in the analysis; 66% female and 34% male, mean age 29.44 ± 8.53 years. Postoperative nausea and vomiting (Kortilla scale), sore throat (visual analogue scale), and dysphagia were evaluated. Statistically significant differences in favour of the without-pack group were found for the variables throat pain at 24 hours (P = 0.002) and dysphagia at 2 hours (P = 0.007) and 24 hours (P < 0.001). There was no difference between the groups regarding postoperative nausea and vomiting (P = 1.00). The results of this study indicate that throat packs as utilized here do not prevent postoperative nausea and vomiting and are associated with worse sore throats and postoperative dysphagia.  相似文献   
158.
A correct balance between endocannabinoid and dopamine‐dependent systems is believed to underlie physiological motor control. We measured the levels of the endocannabinoid anandamide in the cerebrospinal fluid of Parkinson's disease (PD) patients. Subjects were divided into three groups: newly diagnosed de novo patients, subjects undergoing drug withdrawal, and patients under pharmacological therapy. These groups were compared to age‐matched control subjects. Anandamide levels in untreated patients were more than doubled as compared to controls. However, chronic dopaminergic replacement restored control anandamide levels. Abnormal anandamide increase might reflect a compensatory mechanism occurring in course of PD, aimed at normalizing dopamine depletion. © 2010 Movement Disorder Society  相似文献   
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Summary Recent studies suggested that infants delivered after in vitro fertilization and embryo transfer IVFET had low birth weights. To assess further the relationship between birth weight and EGA in these offspring, a review was made of all infants delivered at our institution from May 1, 1983 to July 15, 1986. Forty-five infants in 39 deliveries were identified. Seventeen of 37 (46%) were delivered vaginally, 20 by cesarean section. Forty-two infants were delivered at term (after 36 weeks). The six sets of twins delivered at 254±7 days (mean, 36 weeks). Eighteen of 39 deliveries (46%) delivered at or beyond 40 weeks EGA. The mean weight at delivery for the term infants was 3225±90 g. Thirtyeight infants were size appropriate for dates as assessed by the Lubchenco scale, while the weight in the remaining seven infants exceeded the 90th percentile for their gestational age. We conclude that infants conceived through IVF-ET are not predisposed per se to a low birth weight or delivery at an early gestational age. However, prior studies suggesting lower birth weights for IVF infants may have resulted in part from early delivery due to patient pressure and anxiety.  相似文献   
160.
The effects of chronic treatment with nitric oxide-containing aspirin (NO-aspirin, NCX-4016) in comparison with regular aspirin or placebo on the development of a chronic disease such as atherosclerosis were investigated in hypercholesterolemic low-density lipoprotein (LDL)-receptor-deficient mice. Male mice were assigned randomly to receive in a volume of 10 ml/kg either placebo (n = 10), 30 mg/kg/day NO-aspirin (n = 10), or 18 mg/kg/day of regular aspirin (n = 10). After 12 weeks of treatment, the computer-assisted imaging analysis revealed that NO-aspirin reduced the aortic cumulative lesion area by 39.8 +/- 12.3% compared with that of the placebo (P < 0.001). Regular aspirin did not reduce significantly aortic lesions (-5.1 +/- 2.3%) compared with the placebo [P = 0.867, not significant (NS)]. Furthermore, NO-aspirin reduced significantly plasma LDL oxidation compared with aspirin and placebo, as shown by the significant reduction of malondialdehyde content (P < 0.001) as well as by the prolongation of lag-time (P < 0.01). Similarly, systemic oxidative stress, measured by plasma isoprostanes, was significantly reduced by treatment with NCX-4016 (P < 0.05). More importantly, mice treated with NO-aspirin revealed by immunohistochemical analysis of aortic serial sections a significant decrease in the intimal presence of oxidation-specific epitopes of oxLDL (E06 monoclonal antibody, P < 0.01), and macrophages-derived foam cells (F4/80 monoclonal antibody, P < 0.05), compared with placebo or aspirin. These data indicate that enhanced NO release by chronic treatment with the NO-containing aspirin has antiatherosclerotic and antioxidant effects in the arterial wall of hypercholesterolemic mice.  相似文献   
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