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OBJECTIVE: Prediction of the clinical course of Crohn's disease (CD) is difficult in the long term. Our aim was to determine whether the presence of severe endoscopic lesions (SELs) may predict a higher risk of colectomy and penetrating complications. METHODS: All patients at our institution with active ileocoIonic CD who had colonoscopies between 1990 and 1996 were included in the study. SELs were defined as extensive and deep ulcerations covering more than 10% of the mucosal area of at least one segment of the colon. RESULTS: Among the 102 patients included, 53 had SELs at index colonoscopy. During the follow-up (median = 52 months), 37 patients underwent colonic resection. Probabilities of colectomy at 1, 3, and 8 yr were 20%, 26%, and 42%. Risk of colectomy was independently affected by the presence of SELs at index colonoscopy (relative risk [RR] = 5.43, 95% CI = 2.64-11.18), a Crohn's Disease Activity Index level greater than 288 (RR = 2.21, 95% CI = 1.09-4.47), and the absence of immunosuppressive therapy during the follow-up (RR = 2.44, 95% CI = 1.20-5.00). Probabilities of colectomy were, respectively, 31% and 6% at 1 yr, 42% and 8% at 3 yr, and 62% and 18% at 8 yr in patients with and without SELs. We performed a second analysis excluding the 14 patients operated on within the 3 months after the index colonoscopy: presence of SELs remained the only significant factor predictive of colectomy (RR = 6.72, 95% CI = 2.26-20.03). All six patients with penetrating complications during the follow-up had SELs at index colonoscopy. CONCLUSIONS: Patients with CD exhibiting deep and extensive ulcerations at colonoscopy have a more aggressive clinical course with an increased rate of penetrating complications and surgery.  相似文献   
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The conversion of male germ cell chromatin to a nucleoprotamine structure is fundamental to the life cycle, yet the underlying molecular details remain obscure. Here we show that an essential step is the genome-wide incorporation of TH2B, a histone H2B variant of hitherto unknown function. Using mouse models in which TH2B is depleted or C-terminally modified, we show that TH2B directs the final transformation of dissociating nucleosomes into protamine-packed structures. Depletion of TH2B induces compensatory mechanisms that permit histone removal by up-regulating H2B and programming nucleosome instability through targeted histone modifications, including lysine crotonylation and arginine methylation. Furthermore, after fertilization, TH2B reassembles onto the male genome during protamine-to-histone exchange. Thus, TH2B is a unique histone variant that plays a key role in the histone-to-protamine packing of the male genome and guides genome-wide chromatin transitions that both precede and follow transmission of the male genome to the egg.  相似文献   
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European Journal of Clinical Microbiology & Infectious Diseases - We described three clinical cases of pyogenic liver abscess caused by hypervirulent Klebsiella pneumoniae (hvKp) successfully...  相似文献   
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Diagnosis of intra-abdominal diseases in critically ill patients remains a clinical challenge. Physical examination is unreliable whereas exploratory laparotomy may aggravate patient''s condition and delay further evaluation. Only a few studies have investigated the place of computed tomography (CT) on this hazardous situation. We aimed to evaluate the ability of CT to prevent unnecessary laparotomy during the management of critically ill patients. Charts of all consecutive patients who had undergone an emergency nontherapeutic laparotomy from 1996 to 2013 were retrospectively studied and patient''s demographic, clinical characteristics, and surgical findings were collected. During this period 59 patients had an unnecessary laparotomy. Fifty-one patients had at least one preoperative imaging and 36 had a CT scan. CT scans were interpreted to be normal (n = 12), with minor anomalies (n = 10), or major anomalies (pneumoperitoneum, portal venous gas/pneumatosis intestinalis, thickened gallbladder wall, and small bowel obstruction signs). Surgical exploration was performed through laparotomy (n = 55) or laparoscopy. Overall mortality was 37% with a median survival after surgery of 7 days. In univariate analysis, hospitalization in ICU before surgical exploration was the only factor related to death. In our series CT scans, objectively interpreted, helped avoid unnecessary surgical exploration in 61% of our patients.Key words: Laparotomy, Critical care, Abnormalities, Digestive system, CT scansEarly diagnosis of acute nontraumatic life-threatening intra-abdominal diseases remains a clinical challenge. In critically ill patients, pathologies such as mesenteric ischemia, intestinal perforation, pancreatitis and biliary diseases carry a high mortality rate ranging from 50% to 100%.1,2 For these patients, physical examination can be unreliable due to deep sedation and absence of acute abdomen symptoms, and use of imaging studies may therefore be necessary to identify intra-abdominal pathologies and prevent delay in diagnosis. Also, imaging studies may help avoiding unnecessary laparotomy which can be associated with a morbidity rate up to 22%.3 Ultrasonography (US) can be performed at the bedside and is a good alternative for the diagnosis of biliary tract disease; however, it is highly operator dependent, made difficult by abdominal distension,4 and not effective for bowel perforation or ischemia.5 Computed tomography (CT) scans are increasingly used for emergency patients with acute nontraumatic abdominal pain and tenderness, however, misinterpretation or overinterpretation of CT findings are not rare.6,7 Despite the large use of imaging procedures in the evaluation of intra-abdominal pathologies, few studies have attempted to assess their impact on the management of critically ill patients.8,9 The aim of this observational work was to evaluate the results of preoperative imaging procedures, especially CT, in a consecutive series of nontraumatic critically ill patients who underwent nontherapeutic surgical abdominal exploration in a French university tertiary care hospital.  相似文献   
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