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71.
Increased proliferation and apoptosis of colonic epithelial cells in dextran sulfate sodium-induced colitis in rats 总被引:10,自引:0,他引:10
Vetuschi A Latella G Sferra R Caprilli R Gaudio E 《Digestive diseases and sciences》2002,47(7):1447-1457
We have evaluated morphologic alterations and epithelial cell apoptosis and proliferation of colonic mucosa in the acute and chronic phases of DSS-induced colitis. Colitis was induced in Sprague-Dawley rats by 7 days of 4% DSS oral administration followed by 7 days of tap water for one, two, and three cycles. Control rats receved tap water only. Morphological changes in colonic mucosa were evaluated and scored by light and scanning electron microscopy. Apoptosis was studied by TUNEL assay and cell proliferation by Ki-67 immunoreaction. The expression of both proapoptotic (Fas, FasL, Bax, p53) and antiapoptotic (Bcl2) cellular proteins was determined by immunohistochemistry. Morphologic assessment showed the most severe colonic epithelial lesions and inflammation in the distal colon with a trend to increasing severity from the first to the third DSS cycle. In DSS rats, the epithelial apoptotic index increased 20-fold after the first cycle and 120-fold after the second and third cycles compared with the controls; in the same way, the expression index of proapoptotic proteins (Fas, FasL, Bax, p53) dramatically increased. The proliferative index increased about 40 to 60-fold compared to controls, with no difference among the three DSS cycles. In conclusion, DSS-induced colitis in rats, which has many structural and ultrastructural features similar to those seen in human ulcerative colitis, is a suitable model for studying increased epithelial apoptosis and proliferation. Further studies employing this model will permitt two hypotheses to be tested. (1) Increased apoptosis may lead to a breakdown of the epithelial barrier function and facilitate the mucosal invasion of intraluminal microorganisms and/or antigens. (2) Abnormal and persistent epithelial hyperproliferation could be causally related to the development of colorectal cancers in the setting of chronic colonic inflammation. 相似文献
72.
Giovanni Vennarecci Giuseppe Maria Ettorre Luca Giovannelli Franca del Nonno Letizia Perracchio Paolo Visca Valerio Corazza Antonello Vidiri Giuseppe Visco Eugenio Santoro 《Journal of hepato-biliary-pancreatic sciences》2005,12(4):341-344
We report a new case of benign solitary fibrous tumor (SFT) of the liver. A 65‐year‐old man presented to our unit with upper right abdominal discomfort. On examination abdominal distension was present and palpation showed a large firm mass in the right hypochondrium and epigastrium. The patient's past medical history was not significant and laboratory tests were normal. Ultrasonography and computed tomography showed a large tumor, 20 cm in diameter, in the right lobe of the liver. An extended right hepatectomy was performed. The tumor measured 30 × 28 × 14 cm and weighed 4725 g. Microscopic evaluation showed a benign SFT of the liver with tumor cells typically positive for vimentin and CD34. The postoperative course was uneventful, and the patient is alive 30 months after surgery. This is a rare neoplasm of mesenchymal origin that occasionally involves the liver in adult patients. Most SFTs are benign, but some may have malignant histological features and recur locally or metastasize. Because of their rarity, overall experience has not been significant and little has been published concerning this tumor, Including the present one, 28 cases have been reported in the English literature. Surgery is the mainstay of treatment. Little can be said about the benefits of adjuvant radiochemotherapy in these patients. As SFT of the liver is often a benign neoplasm, chemotherapy or radiotherapy should not be necessary, and should be reserved for when resection is incomplete and/or histological examination reveals features of malignancy. Surgeons must be aware of SFT of the liver, and this neoplasm should be included in the differential diagnosis of a single large hepatic mass. 相似文献
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77.
"Ultrasound comet-tail images": a marker of pulmonary edema: a comparative study with wedge pressure and extravascular lung water 总被引:2,自引:0,他引:2
BACKGROUND: Echographic examination of the lung surface may reveal multiple "comet-tail images" originating from water-thickened interlobular septa. These images could be useful for noninvasive assessment of interstitial pulmonary edema. STUDY OBJECTIVE: The purpose of this study was to assess the diagnostic accuracy of lung comet-tail images compared with chest radiography, wedge pressure, and extravascular lung water (EVLW) quantified by the indicator dilution method (PiCCO System, version 4.1; Pulsion Medical Systems; Munich, Germany). METHODS AND PATIENTS: We enrolled 20 patients (mean age, 62.6 +/- 11.5 years [+/- SD]). Patients were studied before, immediately after, and 24 h following cardiac surgery with chest ultrasound, chest radiography, pulmonary artery catheterization, and the PiCCO system. Performing echo scanning (right and left hemithorax, from second to fourth intercostal space, from parasternal to midaxillary line), an individual patient comet score was obtained by summing the number of comets in each scanned space. RESULTS: A total of 60 comparisons were obtained. Significant positive linear correlations were found between comet score and EVLW determined by the PiCCO System (r = 0.42, p = 0.001), between comet score and wedge pressure (r = 0.48, p = 0.01), and between comet score and radiologic lung water score (r = 0.60, p = 0.0001). CONCLUSIONS: The presence and the number of comet-tail images provide reliable information on interstitial pulmonary edema. Therefore, ultrasonography represent an attractive, easy-to-use, bedside diagnostic tool for assessing cardiac function and pulmonary congestion. 相似文献
78.
Neri E Civeli L Benvenuti A Toscano T Miraldi F Capannini G Muzzi L Sassi C 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2002,29(2):130-132
Although thromboembolism is uncommon during pregnancy and the postpartum period, physicians should be alert to the possibility because the complications, such as pulmonary embolism, are often life threatening. Pregnant women who present with thromboembolic occlusion are particularly difficult to treat because thrombolysis is hazardous to the fetus and surgical intervention by any of several approaches is controversial. A 22-year-old woman, in her 11th week of gestation, experienced an episode of pulmonary embolism and severe ischemic venous thrombosis of the left lower extremity The cause was determined to be a severe protein S deficiency in combination with compression of the left iliac vein by the enlarged uterus. The patient underwent emergency insertion of a retrievable vena cava filter and surgical iliofemoral venous thrombectomy with concomitant creation of a temporary femoral arteriovenous fistula. The inferior vena cava filter was inserted before the venous thrombectomy to prevent pulmonary embolism from clots dislodged during thrombectomy When the filter was removed, medium-sized clots were found trapped in its coils, indicating the effectiveness of this approach. The operation resolved the severe ischemic venous thrombosis of the left leg, and the patency of the iliac vein was maintained throughout the pregnancy without embolic recurrence. At full term, the woman spontaneously delivered an 8-lb, 6-oz, healthy male infant. 相似文献
79.
Eugenio Caturelli Maria Maddalena Squillante Angelo Andriulli Domenico Angelo Siena Caterina Cellerino Francescantonio De Luca Maria Adelaide Marzano Maurizio Pompili Gian Ludovico Rapacclni 《Liver international》1993,13(5):270-273
ABSTRACT— Severe coagulation defects, as reflected by platelet count and prothrombin time, have always been considered a contraindication to needle biopsy of the liver, but there are very limited data on the actual rate of bleeding in patients with such severe alterations and none whatsoever on the bleeding risk associated with newer, fine-gauge needles that produce less trauma to the liver tissue. In addition, there has never been any evidence that platelet count and/or prothrombin time are the most sensitive indices of bleeding risk. This retrospective study of 85 patients, with platelet counts less than 50 000/mm3 and/or prothrombin times less than 50% of controls, subjected to ultrasound-guided fine-needle liver punctures for diagnostic or therapeutic (percutaneous ethanol injection) purposes showed no bleeding episodes after any of the 229 punctures performed. No type of replacement therapy was administered to correct clotting defects prior to the procedure. Correct pathologic diagnoses were obtained in 81.2% of all patients. Ultrasound-guided fine needle puncture appears to be safer than currently believed in patients with severe clotting defects and deserves further evaluation as an alternative to surgical procedures to diagnose and treat liver lesions, even when severe coagulation impairment is present. 相似文献
80.