The PRSS3P2 and TRY7 deletion copy number variant modifies risk for chronic pancreatitis

BACKGROUND

PRSS1 and PRSS2 constitute the only functional copies of a tandemly-arranged five-trypsinogen-gene cluster (i.e., PRSS1, PRSS3P1, PRSS3P2, TRY7 and PRSS2) on chromosome 7q35. Variants in PRSS1 and PRSS2, including missense and copy number variants (CNVs), have been reported to predispose to or protect against chronic pancreatitis (CP). We wondered whether a common trypsinogen pseudogene deletion CNV (that removes two of the three trypsinogen pseudogenes, PRSS3P2 and TRY7) might be associated with CP causation/predisposition.

METHODS

We analyzed the common PRSS3P2 and TRY7 deletion CNV in a total of 1536 CP patients and 3506 controls from France, Germany, India and Japan by means of quantitative fluorescent multiplex polymerase chain reaction.

RESULTS

We demonstrated that the deletion CNV variant was associated with a protective effect against CP in the French, German and Japanese cohorts whilst a trend toward the same association was noted in the Indian cohort. Meta-analysis under a dominant model yielded a pooled odds ratio (OR) of 0.68 (95% confidence interval (CI) 0.52-0.89; p = 0.005) whereas an allele-based meta-analysis yielded a pooled OR of 0.84 (95% CI 0.77-0.92; p = 0.0001). This protective effect is explicable by reference to the recent finding that the still functional PRSS3P2/TRY7 pseudogene enhancers upregulate pancreatic PRSS2 expression.

CONCLUSIONS

The common PRSS3P2 and TRY7 deletion CNV was associated with a reduced risk for CP. This finding provides additional support for the emerging view that dysregulated PRSS2 expression represents a discrete mechanism underlying CP predisposition or protection.

EUS-guided choledochoduodenostomy by use of electrocautery-enhanced lumen-apposing metal stents: a French multicenter study after implementation of the technique (with video)

BACKGROUND AND AIMS

EUS-guided biliary drainage is indicated in cases of impossibility or failure of classic biliary drainage by ERCP. Recently we reported good efficiency of EUS-guided choledochoduodenostomy (EUS-CDS) using the electrocautery-enhanced lumen-apposing metal stent (ECE-LAMS) in a retrospective multicenter study. Use of the recommended technique (direct puncture with the ECE-LAMS with use of a pure cut current and a 6-mm stent) was the only predictive factor of clinical success. We re-evaluated this procedure after 1 year in the same centers.

METHODS

This was a French retrospective multicenter study of a prospective database including all cases of EUS-guided CDS with ECE-LAMS in the 7 centers that participated in the first study.

RESULTS

Seventy consecutive patients were included in this study between September 1, 2017, and September 22, 2018. Failure of primary ERCP was due to duodenal stenosis in 44% of cases and to tumoral infiltration of the papilla in 22% of cases. The mean duration of the procedure was 5 ± 3 minutes. The recommended technique was used in 98.5% of cases. The technical and clinical success rates were both 97.1% (69/70). Short-term adverse events (periprocedural and intrahospital) occurred in 1.6%.

CONCLUSIONS

EUS-CDS with the ECE-LAMS is efficacious and safe in distal malignant obstruction of the common bile duct in cases of ERCP failure with impressive results once expertise is acquired and the recommended technique (direct fistulotomy, pure cut current, and 6-mm stent) is followed.

Endoscopic ultrasound-guided choledochoduodenostomy with electrocautery-enhanced lumen-apposing stents: a retrospective analysis

BACKGROUND

Endoscopic ultrasound-guided biliary drainage is an alternative to percutaneous biliary drainage in cases of malignant biliary obstruction and failure of classic endoscopic drainage by endoscopic retrograde cholangiopancreatography (ERCP). Recently, a new electrocautery-enhanced lumen-apposing metal stent (ECE-LAMS) that allows for endoscopic anastomosis (apposition stent) has become available for use in EUS-choledochoduodenostomy (EUS-CDS) and facilitates the procedure.

METHODS

This was a retrospective study of all EUS-CDS procedures performed in France between April 2016 and August 2017. The primary end point was the technical and clinical success rates of EUS-CDS using an ECE-LAMS.

RESULTS

52 consecutive patients were included in the study. The etiology of distal bile duct obstruction was distal pancreatic adenocarcinoma in 43 patients (82.7 %). The technical success rate was 88.5 % (46 /52 patients), and the clinical success rate was 100 % (46/46 patients). The mean duration of the procedure was 10.2 minutes (range 1 - 90). Two patients (3.8 %) presented with short-term complications after EUS-CDS and before discharge from hospital. In univariate analyses, a small diameter of the common bile duct and not following the recommended procedure technique were significant risk factors for technical failure. Over a mean follow-up of 157 days, the median survival time without biliary complications was 135 days.

CONCLUSION

EUS-CDS with an ECE-LAMS is efficacious and safe in distal malignant obstruction of the common bile duct and could be proposed as the first option in cases of ERCP failure.

Spatial Distribution of Coffee Wilt Disease Under Roguing and Replanting Conditions: A Case Study from Kaweri Estate in Uganda

Based on time and spatial dynamic considerations, this study evaluates the potential role of short- and long-distance dispersal in the spread of coffee wilt disease (CWD) in a large commercial Robusta coffee estate in Uganda (Kaweri, 1,755 ha) over a 4-year period (2008 to 2012). In monthly surveys, total disease incidence, expansion of infection foci, and the occurrence of isolated infected trees were recorded and submitted to spatial analysis. Incidence was higher and disease progression faster in old coffee plantings compared with young plantings, indicating a lack of efficiency of roguing for reducing disease development in old plantings. At large spatial scale (approximately 1 km), Moran indices (both global and local) revealed the existence of clusters characterized by contrasting disease incidences. This suggested that local environmental conditions were heterogeneous or there were spatial interactions among blocks. At finer spatial scale (approximately 200 m), O-ring statistics revealed positive correlation between distant infection sites across distances as great as 60 m. Although these observations indicate the role of short-distance dispersal in foci expansion, dispersal at greater distances (>20 m) appeared to also contribute to both initiation of new foci and disease progression at coarser spatial scales. Therefore, our results suggested the role of aerial dispersal in CWD progression.

Molecular mapping of genes conferring field resistance to South American Leaf Blight ( Microcyclus ulei) in rubber tree

The South American Leaf Blight (SALB), caused by the fungus Microcyclus ulei, is the major rubber tree disease in all Central and South America. A population of 192 progeny individuals derived from a cross between a resistant clone and a susceptible cultivated clone was planted in a field trial in French Guiana in order to evaluate the resistance parameters under real infestation conditions. The resistance type (RT), the presence of stromata (ST) and the level of attack (AT) were observed 20-times on a 22-months period, and semi-quantitative evaluation of stromata was registered only once. The search for QTLs was performed using the Kruskal-Wallis test, Interval Mapping and the Composite Interval Mapping method. One major QTL located on linkage group g13 was detected on the RO 38 map, responsible for 36 to 89% of the phenotypic variance of resistance. This resistance QTL corresponds to one that had previously been detected under controlled conditions of infestation and we called it M13-1bn. Surprisingly, the effect of this QTL was larger under natural conditions of infestation than under controlled inoculation. Other minor QTLs (four on the RO38 map and one on the PB 260 map) were also detected. The type of resistance brought by M13-1bn, as well as its durability, are discussed. Applications for rubber tree breeding programs are considered.