Common variants in the CLDN2-MORC4 and PRSS1-PRSS2 loci confer susceptibility to acute pancreatitis

Background/Objectives

Acute pancreatitis (AP) is one of the most common gastrointestinal disorders often requiring hospitalization. Frequent aetiologies are gallstones and alcohol abuse. In contrast to chronic pancreatitis (CP) few robust genetic associations have been described. Here we analysed whether common variants in the CLDN2-MORC4 and the PRSS1-PRSS2 locus that increase recurrent AP and CP risk associate with AP.

Chronic pancreatitis: beyond alcohol

For many years, the classification of chronic pancreatitis has been oversimplified according to whether the cause is alcoholic (60-70% of cases according to published series) or non-alcoholic (20-40% of the remaining cases). Recognition of smoking as an important risk factor and increasing identification of factors of genetic susceptibility have placed these percentages in doubt and have led to a reconceptualization of the disease as a multifactorial process. Mutations in the PRSS1, SPINK1 and CFTR genes have been confirmed as major risk factors, while mutations in the CTRC and CASR genes are considered lesser risk factors for the development of chronic pancreatitis. These genetic variants are expressed in a much higher percentage of patients with chronic pancreatitis than could be expected by chance. The trans-heterozygous combination multiplies the risk of chronic pancreatitis and demonstrates the degree of complexity of the etiopathogenic mechanisms of the disease. Ductal obstruction and autoimmunity are other important etiologic factors of chronic pancreatitis that need a specific review. The present article reviews the latest studies evaluating the role of alcohol and smoking in chronic pancreatitis and the most significant genetic factors.     

Mutational screening of the cationic trypsinogen gene in a large cohort of subjects with idiopathic chronic pancreatitis

Several missense mutations, including R122H, N29I, K23R, A16V and D22G, in the cationic trypsinogen gene (PRSS1), have been associated with certain forms of hereditary pancreatitis (HP). Their occurrence in the idiopathic chronic pancreatitis (ICP) and whether novel mutations could be identified in PRSS1 remain to be further evaluated. These were addressed by the mutational screening of the entire coding sequence and the intronic/exonic boundaries of the PRSS1 gene in 221 ICP subjects, using a previously established denaturing gradient gel electrophoresis technique. Among the known PRSS1 mutations, only the R122H was detected in a single subject and the A16V in two subjects in the cohort, strengthening that HP-associated PRSS1 mutations are rare in ICP. Additional missense mutations, including P36R, E79K, G83E, K92N and V123M, were identified once separately. By analogy with the known PRSS1 mutations, predisposition to pancreatitis by some of them, particularly the V123M autolysis cleavage site mutation, is suspected. Functional analysis is expected to clarify their possible medical consequences.     

颅盆环牵引及后路内固定技术治疗重度脊柱侧弯

目的:研究应用颅盆环牵引及后路内固定技术治疗重度脊柱侧弯的疗效。方法:78例病人均采用颅盆环牵引及后路脊柱侧弯板棍系统(PRSS)内固定技术治疗。结果:78例病人术前平均角130.3°,术后矫正为58.1°,平均矫正率55.4%,身高平均增高6.8cm,脊柱畸形及骨盆倾斜得到明显改善。术后并发轻度腹胀12例,无瘫痪及其他并发症发生。结论:对于重度脊柱侧弯,采用颅盆环牵引及后路PRSS内固定技术治疗可增强矫形效果,减少术中及术后并发症的发生。     

胰蛋白酶原基因缺失突变导致早发型自身免疫性相关的多器官多发囊肿的研究

目的：探讨由胰蛋白酶原基因（cationic trypsinogen, PRSS1）突变引发的早发型自身免疫性相关的多器官多发囊肿及其致病机制。方法采用DNA全长测序技术分析PRSS1、囊性纤维化跨膜通道调节因子（cystic fibrosis transmembrane conductance regulator, CFTR）、丝氨酸蛋白酶抑制剂 Kazal 1型（serine protease inhibitor Kazal type 1, SPINK1）、蛋白激酶D（protein kinase D, PKD）1和PKD2等胰腺炎和多囊性病变相关基因的所有外显子及其侧翼内含子剪切区域,确定DNA和cDNA序列的变异,通过与家系内部和正常对照的比较分析,对检测到的变异是否与疾病相关进行探讨,并构建突变体表达体系进行功能学验证,同时对患者的肺、肝、胰腺等穿刺样本进行免疫组织化学和特殊染色。结果在2例年轻的自身免疫性胰腺炎患者中首次发现PRSS1基因2号外显子缺失突变生成激活肽缺失型的胰蛋白酶原,并具有生物学活性;肝脏、肺穿刺病理均可见不同程度的淋巴细胞和浆细胞浸润,肺组织病理显示弹力纤维、网状纤维明显减少;患者表现为多脏器多囊性病变,血清胰蛋白酶、弹力蛋白酶、AAT显著增高。使用糖皮质激素治疗有效。结论 PRSS1：c．1300_1304 del CCCAG是引发早发型自身免疫性胰腺炎的新突变形式,并与多器官囊肿关系密切。     

Novel Mutations of PRSS1 Gene in the Patients with Pancreatic Cancer among Han Population

Purpose: The aim of this study was to elaborate some novel mutations of PRSS1 gene in the patients with pancreatic cancer. Patients and Methods: There were 156 patients with pancreatic cancer and 220 unrelated individuals were studied as controls. The mutations of PRSS1 gene were analyzed by direct sequencing. K-ras Mutation Detection Kit was used to find the general k-ras gene disorder in the pancreatic cancer tissue. Then collected and analyzed the clinical data at the same time. Results: There were two patients carried novel mutations which is IVS 3 +157 G>C of PRSS1 gene from peripheral blood specimens and pancreatic cancer tissue. What’s more, we were surprised to find a novel complicated mutation of exon 3 in PRSS1 gene (c.409 A>G and c.416 C>T) in another young patient. The c complicated mutation made No.135 and No.137 amino acid transfer from Thr to Ala and Thr to Met respectively. All of the mutations weren’t found in the normal controls and no mutations of k-ras gene detected in the three patients. Conclusion: These observations imdicate that mutations of PRSS1 gene may be an important factor of pancreatic cancer.     

原发性腹膜后软组织肉瘤预后因素的COX模型分析

自１９６４年４月至１９９２年４月，我院共收治原发性腹膜后软组织肉瘤４８例，总的２．５，１０年生存率为５７．８％，２２．４％和１０．７％，本文运用ＣＯＸ模型，对可能影响本病预后的有关因素，分别作单因素及多因素分析，分析结果表明肿瘤有无全切除，是影响本病预后的最重要因素，因此，我们主在明确本病诊断后，尽可能完全切除肿瘤，对术后复发者，也要争取再次，多次手术切除，术后酌情辅加放疗。     

Porcine kallikrein-4 activation,glycosylation, activity,and expression in prokaryotic and eukaryotic hosts

Kallikrein-4 (KLK4) is a serine proteinase believed to be important in the normal development of dental enamel. We isolated native KLK4 from developing pig enamel and expressed four recombinant forms. Pig KLK4 was expressed in bacteria with and without the propeptide, and in two eukaryotic systems. Recombinant pig KLK4 was secreted as a zymogen by '293' cells and purified. The proKLK4 was activated in vitro by thermolysin and recombinant pig enamelysin, but not by native KLK4. These results were confirmed using a fluorescent peptide analog of the KLK4 propeptide-enzyme junction. Native KLK4 appears as a doublet at 37 kDa and 34 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Removal of N-linked oligosaccharides by digestion with deglycosidase-F reduced the doublet to a single band at approximately 28 kDa, demonstrating that the active enzyme is glycosylated, and that the 37 kDa and 34 kDa forms differ only in their number of glycosylations. Deglycosylation was also associated with a loss of proteolytic activity. We digested recombinant pig amelogenin with native KLK4 and characterized the cleavage products by N-terminal sequencing and mass spectrometry. Eleven cleavage sites in the amelogenin protein were identified, demonstrating that KLK4 degrades amelogenin and is likely to participate in the degradation of enamel proteins in vivo.