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Bone marrow stem cells for urologic tissue engineering 总被引:1,自引:0,他引:1
OBJECTIVES: Experiments in rats and dogs have demonstrated the potential of bone marrow-derived mesenchymal stem cells (MSCs) for urinary tract tissue engineering. However, the small graft size in rats and a failure to identify the MSCs in engineered tissues made it difficult to assess the true potential of these cells. Our goals were to characterize MSCs from pigs, determine their ability to differentiate into smooth muscle cells (SMCs) and use them in an autologous augmentation cystoplasty. METHODS: MSCs were isolated from pigs and analyzed for common markers of MSCs by flow cytometry. SMC differentiation was determined by immunoblotting. MSCs were isolated, genetically labeled, expanded in vitro, seeded onto small intestinal submucosa (SIS) and used for autologous bladder augmentation. RESULTS: Porcine MSCs are morphologically and immunophenotypically similar to human MSCs. Culturing MSCs at low density enhances proliferation rates. MSCs consistently differentiate into mature SMCs in vitro when maintained at confluence. Labeled MSCs grew on SIS over one week in vitro and survived a 2-week implantation as an autologous bladder augment in vivo. Some label-positive cells with SMC morphology were detected, but most SMCs were negative. Notably, many cells with a urothelial morphology stained positively. CONCLUSIONS: Porcine MSCs have similar properties to MSCs from other species and consistently undergo differentiation into mature SMC in vitro under specific culture conditions. Labeled MSCs within SIS may assist tissue regeneration in augmentation cystoplasty but may not significantly incorporate into smooth muscle bundles. 相似文献
33.
Finucane BT Ganapathy S Carli F Pridham JN Ong BY Shukla RC Kristoffersson AH Huizar KM Nevin K Ahlén KG;Canadian Ropivacaine Research Group 《Anesthesia and analgesia》2001,92(5):1276-1285
We evaluated the safety and efficacy of a 72-h epidural infusion of ropivacaine and measured the impact of adding fentanyl 2 microg/mL to the required infusion rate, on the quality of postoperative pain relief and the incidence of side effects, after colonic surgery. One hundred fifty-five patients scheduled for elective colonic surgery were randomized in this trial. Epidural infusions of ropivacaine 2 mg/mL with fentanyl 2 microg/mL (R + F) and without fentanyl (R) were commenced during surgery and continued for 72 h postoperatively. This was a prospective, randomized, double-blinded, multi-center trial. The median infusion rate required was less in the R + F group (9.3 vs 11.5 mL/h, P < 0.001). Median pain scores at rest and on coughing were lower in the R + F group (P < 0.0001). The incidence of hypotension was more in the R + F group (P = 0.01). Time to readiness for discharge was delayed in the R + F group (median 6.6 vs 5.5 days, P = 0.012). The addition of fentanyl to ropivacaine resulted in decreased infusion rates and enhanced pain control; however, adverse effects were increased and readiness to discharge was delayed. IMPLICATIONS: Epidural infusions of ropivacaine with and without fentanyl were administered to patients to control pain after colonic surgery. Patients who received ropivacaine with fentanyl had better pain control, increased side effects, and delayed readiness to discharge. This study questions the value of adding opioids to epidural infusions of local anesthetics. 相似文献
34.
Carcinoma gallbladder is the commonest malignancy in the Northern part of India. The heavy metals are known carcinogens while trace metals have protective effect. Aim The aim of the study is to estimate the heavy and trace metal (Lead, Zinc, Copper, Cadmium, Chromium, Manganese and Selenium) concentration in serum, bile, tissue and gallstone in patients with gallbladder diseases. Method This is a pilot study conducted in 45 cases (Group – I: 15 cases of carcinoma gallbladder, Group II: 15 patients of cholecystitis with cholelithiasis and Group – III: 15 patients of healthy control), to detect the relationship between the heavy and trace metal concentration and gall bladder carcinoma. Analysis of metal was done using Perkins‐Elmer model 2380 atomic absorption spectrophotometer. Results The serum concentration of copper and nickel was significantly high in carcinoma gallbladder patients as compared to patients with cholecystitis while zinc and selenium is low in carcinoma gallbladder patients. Bile concentration of zinc, selenium and manganese was significantly low in carcinoma gallbladder patients (p < 0.05) as compared to patients of cholelithiasis while cadmium and nickel was high. Tissue concentration of manganese was significantly low in carcinoma gallbladder patients as compared to patients of cholelithiasis while chromium was high. Gallstone concentration of copper, manganese and lead was significantly low in carcinoma gallbladder patients as compared to patients of cholelithiasis. Conclusion The heavy metals are in higher concentration in carcinoma gallbladder while trace metals are in lower concentration indicating possible role of heavy metal in gallbladder carcinogenesis. 相似文献
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The herniation of abdominal contents through a diaphragmatic and chest wall rent has been uncommonly reported in literature. Also known as a transdiaphragmatic intercostal hernia (TDIH) or intercostal pleuroperitoneal hernia, it occurs when the disruption of diaphragmatic or intercostal muscles leads to an acquired herniation of abdominal contents. It is usually seen to occur following a traumatic incident. We report the case of an elderly male who presented with a reducible lump in the left chest and breathlessness on exertion, in the absence of any trivial or occult trauma, and how this was managed adequately via surgery alone. 相似文献
38.
Yogesh S Kashyap P S Yadav Tushar Roy P S Sarkar M Shukla Amar Sinha 《Applied radiation and isotopes》2008,66(8):1083-1090
In-line X-ray phase-contrast imaging technique is an emerging method for the study of materials such as carbon fibers, carbon composite materials, polymers, etc. Similarly this technique is also well suited for the imaging of soft materials such as tissues, distinguishing between tumor and normal tissue. These represent the class of materials for which X-ray attenuation cross-section is very small. Thus this method promises a far better contrast for low X-ray absorbing substances than the conventional radiography method. We have set up an experimental facility using a combination of X-ray CCD detector and a microfocus X-ray source. This facility is dedicated to micro-imaging experiments such as microtomography and high-resolution phase-contrast experiments. In this paper, the results of X-ray phase-contrast imaging experiments are described. 相似文献
39.
Background
A perfect rotational alignment could be achieved if the implant rotation is individualized for each knee before operation. The anatomic transepicondylar axis (aTEA) is a standard reference for setting the femoral component rotation. Intraoperative localization of aTEA is difficult. However, aTEA could be readily identified on preoperative CT scans, and condylar twist angle (CTA) could be determined preoperatively. The femoral component can subsequently be implanted according to CTA. Therefore, perfect intraoperative rotational alignment can be easily achieved. The aim of the study was to evaluate the role of preoperative calculation of CTA by CT scan in optimizing femoral component rotation during TKA.Materials and methods
We analyzed fifty-three total knee arthroplasty in 36 primary osteoarthritis patients, aged 49–78 years. CTA was measured on preoperative CT scan. Intraoperative equal magnitude of external rotation was set so that the femoral cut was parallel to aTEA. Postoperative CT scan was done to confirm the femoral component rotation.Results
Postoperatively, femoral component was parallel to aTEA with a mean error of 0.77°. In 34 knees (64.15%), surgical transepicondylar axis (sTEA) could also be determined; average angle between sTEA and aTEA was 4.65°. Femoral component in these knees was found to be parallel or externally rotated in relation to sTEA (mean 4.22°).Conclusion
Preoperative calculation of CTA by CT scan helps to optimize the femoral component rotation during TKA.40.