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231.
Pancreatic cancer currently has no subtypes that inform clinical decisions; hence, there exists an opportunity to rearrange the morphological and molecular taxonomy that guides a better understanding of tumor characteristics. Nonetheless, accumulating studies to date have revealed the large-duct type variant, a unique subtype of pancreatic ductal adenocarcinoma (PDA) with cystic features. This subtype often radiographically mimics intraductal papillary mucinous neoplasms (IPMNs) and involves multiple small cysts occasionally associated with solid masses. The “bunch-of-grapes” sign, an imaging characteristic of IPMNs, is absent in large-duct PDA. Large-duct PDA defines the mucin profile, and genetic alterations are useful in distinguishing large-duct PDA from IPMNs. Histologically, neoplastic ducts measure over 0.5 mm, forming large ductal elements. Similar to classic PDAs, this subtype is frequently accompanied by perineural invasion and abundant desmoplastic reactions, and KRAS mutations in codon 12 are nearly ubiquitous. Despite such morphological similarities with IPMNs, the prognosis of large-duct PDA is equivalent to that of classic PDA. Differential diagnosis is therefore essential.  相似文献   
232.
《Pancreatology》2022,22(6):698-705
BackgroundThe functional and morphological recovery following an episode of acute pancreatitis (AP) in children still remains ill understood as research exploring this is limited. We aimed to characterize the morphological and functional changes in pancreas following AP and ARP (acute recurrent pancreatitis) in children.MethodsChildren with AP were followed prospectively and assessed at two time points at least 3 months apart, with the first assessment at least 3 months after the AP episode. Exocrine and endocrine functions were measured using fecal elastase and fasting blood sugar/HbA1c levels respectively. Morphological assessment was done using endoscopic ultrasound (EUS) and magnetic resonance imaging and cholangiopancreatography (MRI/MRCP).ResultsSeventy-three children (boys:59%; mean age:8.4 ± 3.2years) were studied and 21 of them (29%) progressed to ARP. Altered glucose homeostasis was seen in 19 (26%) at first and 16 (22%) at second assessment and it was significantly more in ARP group than the AP group at first (42.8%vs19.2%; p = 0.03) as well as second assessment (38.1%vs15.3%; p = 0.03). Twenty-one children (28.7%) at first and 24 (32.8%) at second assessment developed biochemical exocrine pancreatic insufficiency. EUS detected indeterminate and suggestive changes of chronic pancreatitis in 21% at first (n = 38) and 27.6% at second assessment (n = 58). On MRCP, main pancreatic duct and side branch dilatation were seen in 15 (20.5%) and 2 (2.7%) children respectively.ConclusionsMore than one-quarter of children have evidence of altered glucose homeostasis and biochemical exocrine pancreatic insufficiency following an episode of AP. Similarly, morphological features of chronicity seen in some of the children suggest that a fraction of subjects may develop chronic pancreatitis on longer follow-up.  相似文献   
233.
《Pancreatology》2022,22(6):810-816
BackgroundIncreased postoperative serum amylase has been recently reported to be associated with increased postoperative morbidity, but studies on postoperative serum lipase are limited. The aim of this study was to evaluate the value of postoperative serum lipase in predicting clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD).MethodA retrospective analysis was performed on 212 patients who underwent PD from September 2018 and March 2021, focusing on the association between postoperative day (POD) 1 serum lipase and CR-POPF.ResultsOverall, 108 (50.9%) patients had elevated serum lipase levels (>68 U/L) on POD 1. Patients with elevated serum lipase exhibited a significantly higher incidence of CR-POPF (37.0% vs. 6.7%, p < 0.001). Receiver operating characteristic (ROC) analyses showed improved diagnostic accuracy for POD 1 serum lipase compared with POD 1 serum amylase in predicting CR-POPF (AUC: 0.801 vs. 0.745, p = 0.029). Elevated serum lipase on POD 1 and elevated serum CRP on POD 3 were identified as independent predictors of CR-POPF. A simple early postoperative model, consisting of POD 1 serum lipase levels and POD 3 serum CRP levels, showed good discrimination (AUC 0.76, 95% CI 0.69–0.83) to identify the onset of CR-POPF.ConclusionSerum lipase on POD 1 outperformed serum amylase on POD 1 in predicting CR-POPF after PD. The combination of POD 1 serum lipase and POD 3 serum CRP provides a reliable predicting model for CR-POPF.  相似文献   
234.
目的 分析胰源性区域性门静脉高压(pancreatogenic segmental portal hypertension,PSPH)的多层螺旋CT(MSCT)表现,探讨MSCT对该病的诊断价值.方法 使用16排螺旋CT对42例PSPH患者行上腹部CT平扫及增强扫描,采用图像后处理技术显示脾静脉及侧枝血管情况.结果 孤立性脾静脉阻塞30例,其侧支血管食管静脉(9.5%)、胃冠状静脉(76.19%)、胃短静脉(85.71%)、胃网膜静脉(95.24%)、胃结肠干(23.81%)曲张;非孤立性脾静脉栓塞12例,其中伴肠系膜上静脉阻塞8例,其属支胃结肠干(19.05%)、结肠右上静脉(16.67%)、结肠中静脉(14.29%)、胰十二指肠前上静脉(19.05%)有不同程度曲张.伴门静脉海绵样变5例.结论 MSCT对PSPH的脾静脉阻塞及其胃周迂曲扩张的侧枝静脉显示具有重要价值.  相似文献   
235.
Summary Conclusion Stimulation of pancreatic sensory nerves by capsaicin produced secretory effects probably caused, at least in part, by the release of CGRP. Background In the pancreas calcitonin gene-related peptide (CGRP) has been localized in the sensory nerves, but its physiological role is unknown. This study was undertaken to compare the changes of pancreatic enzyme secretion produced by CGRP and by stimulation or destruction of sensory nerves. Methods To stimulate sensory nerves, low doses of capsaicin (0.25–0.5 mg/kg) were given intraduodenally to the conscious rats with chronic pancreatic fistula. To inactivate sensory nerves high doses of capsaicin (100 mg/kg) were given subcutaneously 10 d before tests. For the in vitro experiments pancreatic slices and isolated pancreatic acini were prepared from intact and capsaicin-denervated rats. Results In conscious rats, CGRP given subcutaneously (5–10 μg/kg) and low doses of capsaicin given intraduodenally reduced basal pancreatic secretion. In isolated pancreatic acini, CGRP (10−10–10−6 M), but not capsaicin, increased basal or secretagog-stimulated amylase release. In pancreatic slices (containing nerve fibers) capsaicin (10−10–10−6 M) increased enzyme secretion, and this secretion was abolished by previous inactivation of sensory nerves by this neurotoxin. Capsaicin deactivation did not affect the secretory response of pancreatic acini to CGRP, cerulein, or urecholine. Sensory denervation by capsaicin did not change basal protein secretion, but reduced that produced by feeding or diversion of pancreatic juice to the exterior during first 2 h of the tests.  相似文献   
236.
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237.
Summary Regenerating islets can be induced by the administration of poly(ADP-ribose) synthetase inhibitors to 90% depancreatized rats. In screening a regenerating isletderived cDNA library, we previously isolated a novel gene, reg (regenerating gene), which encodes a 165-amino acid protein with a 21-amino acid signal sequence. In the present study, we have examined the expression and localization of reg protein in the regenerating islets by immunocytochemical techniques using a monoclonal antibody against a recombinant rat reg protein of 144 amino acids without the signal sequence. Light microscopy examination showed strong immunoreactivity for reg protein in the regenerating islets of the rats at two weeks and two months after the 90% pancreatectomy, whereas reg protein was almost undetectable in normal rat islets or in the islets of the rats one year after the pancreatectomy. Almost all the reg protein-positive cells were stained for insulin. By applying the immunogold technique at the ultrastructural level, it was demonstrated that both reg protein and insulin occur in the central granular core of the regenerating Beta cell secretory granules. These results suggest that reg protein is synthesized in and secreted from the regenerating Beta cells and that its expression is closely associated with Beta-cell regeneration.  相似文献   
238.
Summary Systematic sampling of human necropsy pancreases has revealed that pancreatic polypeptide (PP) cells are not distributed equally in the gland. PP-cells are the most abundant cell type in the posterior part of the pancreatic head while they are scarce or absent in the remainder of the gland. The PP-rich part of the head can be separated by blunt dissection from the pancreas as a discrete lobe. This lobe probably originates from the ventral pancreatic bud during embryogenesis. A quantitative study of the immunofluorescent endocrine cell types (insulin, glucagon, somatostatin and pancreatic polypeptide cells) in PP-rich and PP-poor regions of pancreases in 8 subjects with ages ranging from 33 fetal weeks to 80 years, showed that the proportions of the cell types were different in youngs and adults.  相似文献   
239.
Summary Islet amyloid polypeptide or amylin is a polypeptide secreted mainly from the pancreatic beta cells together with insulin upon stimulation. High levels of islet amyloid polypeptide have also been shown to increase the peripheral insulin resistance and consequently a role for islet amyloid polypeptide in the glucose homeostasis has been suggested. We have studied the glucose homeostasis in a patient with a malignant endocrine pancreatic tumour producing large amounts of an islet amyloid polypeptide-like molecule (about 400 times the upper reference level for islet amyloid polypeptide). This patient developed insulin-requiring diabetes mellitus shortly after the tumour diagnosis. Both intravenous and oral glucose tolerance tests revealed inhibited early responses in insulin and C-peptide release, but the insulin and C-peptide response to glucagon stimulation was less affected. Aneuglycaemic insulin clamp showed normal insulin-mediated glucose disposal. In vitro experiments, where isolated rat pancreatic islets were cultured with serum from the patient, showed a moderately decreased islet glucose oxidation rate and glucose-stimulated insulin release compared to islets cultured with serum from healthy subjects. However, culture of rat islets with normal human serum supplemented with synthetic rat islet amyloid polypeptide did not affect the glucose-stimulated insulin release. In conclusion, the observed effects show that the diabetic state in this patient was associated with an impaired glucose-stimulated insulin release but not with an increased peripheral insulin resistance. Thus, the results suggest that if islet amyloid polypeptide has diabetogenic effects they are more likely to be exerted at the level of insulin secretion than at the level of peripheral insulin sensitivity.  相似文献   
240.
《Pancreatology》2020,20(8):1592-1597
ObjectivesDespite substantial morbidity and mortality associated with acute pancreatitis (AP), only one small randomized controlled drug trial (RCT) is available in the past few decades from the United States. Hence, we conducted a single-center, double-blind, placebo-controlled RCT of pentoxifylline in AP.MethodsA total of 9 doses of oral pentoxifylline 400 mg or placebo tablet, three times daily, was administered within 72 h of diagnosis, using randomization blocks by pharmacy. Primary outcome was a composite outcome including any of the following: death, peripancreatic and/or pancreatic necrosis, infected pancreatic necrosis, persistent organ failure, persistent systemic inflammatory response syndrome, hospital stay longer than 4 days, need for intensive care, and need for intervention for necrosis.ResultsBetween July 7, 2015, and April 4, 2017, we identified 685 patients with AP, 233 met eligibility criteria and 176 were approached for the study. Of these, 91 (51.7%) declined and finally 45 in pentoxifylline group and 38 in placebo group (83 total) were compared. There were no significant differences in primary outcome (27 [60.0%] vs 15 [39.5%]; P = .06). Pentoxifylline group was not associated with any benefit, but withlonger stay (42% vs. 21%; P = .04) and higher readmission rates (16 %vs 3%; P = .047).ConclusionsWe could not demonstrate superiority of pentoxifylline over placebo. Smaller sample size and inclusion of all types of severity might be the reasons for lack of efficacy. The challenges observed in the present study indicate that, in order to conduct a successful drug trial in AP, a multi center collaboration is essential.  相似文献   
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