Efficiency of stress-adaptive traits chlorophyll fluorescence and membrane thermo- stability in wheat under high temperature

Despite developments in targeted gene sequencing and whole-genome analysis techniques, the robust detection of all genetic variation, including structural variants, in and around genes of interest and in an allele-specific manner remains a challenge. Here we present targeted locus amplification (TLA), a strategy to selectively amplify and sequence entire genes on the basis of the crosslinking of physically proximal sequences. We show that, unlike other targeted re-sequencing methods, TLA works without detailed prior locus information, as one or a few primer pairs are sufficient for sequencing tens to hundreds of kilobases of surrounding DNA. This enables robust detection of single nucleotide variants, structural variants and gene fusions in clinically relevant genes, including BRCA1 and BRCA2, and enables haplotyping. We show that TLA can also be used to uncover insertion sites and sequences of integrated transgenes and viruses. TLA therefore promises to be a useful method in genetic research and diagnostics when comprehensive or allele-specific genetic information is needed

Identification of Srp9 as a febrile seizure susceptibility gene

Objective: Febrile seizures (FS) are the most common seizure type in young children. Complex FS are a risk factor for mesial temporal lobe epilepsy (mTLE). To identify new FS susceptibility genes we used a forward genetic strategy in mice and subsequently analyzed candidate genes in humans. Methods: We mapped a quantitative trait locus (QTL1) for hyperthermia-induced FS on mouse chromosome 1, containing the signal recognition particle 9 (Srp9) gene. Effects of differential Srp9 expression were assessed in vivo and in vitro. Hippocampal SRP9 expression and genetic association were analyzed in FS and mTLE patients. Results: Srp9 was differentially expressed between parental strains C57BL/6J and A/J. Chromosome substitution strain 1 (CSS1) mice exhibited lower FS susceptibility and Srp9 expression than C57BL/6J mice. In vivo knockdown of brain Srp9 reduced FS susceptibility. Mice with reduced Srp9 expression and FS susceptibility, exhibited reduced hippocampal AMPA and NMDA currents. Downregulation of neuronal Srp9 reduced surface expression of AMPA receptor subunit GluA1. mTLE patients with antecedent FS had higher SRP9 expression than patients without. SRP9 promoter SNP rs12403575(G/A) was genetically associated with FS and mTLE. Interpretation: Our findings identify SRP9 as a novel FS susceptibility gene and indicate that SRP9 conveys its effects through endoplasmic reticulum (ER)-dependent synthesis and trafficking of membrane proteins, such as glutamate receptors. Discovery of this new FS gene and mechanism may provide new leads for early diagnosis and treatment of children with complex FS at risk for mTLE

Global lake responses to climate change

Climate change is one of the most severe threats to global lake ecosystems. Lake surface conditions, such as ice cover, surface temperature, evaporation and water level, respond dramatically to this threat, as observed in recent decades. In this Review, we discuss physical lake variables and their responses to climate change. Decreases in winter ice cover and increases in lake surface temperature modify lake mixing regimes and accelerate lake evaporation. Where not balanced by increased mean precipitation or inflow, higher evaporation rates will favour a decrease in lake level and surface water extent. Together with increases in extreme-precipitation events, these lake responses will impact lake ecosystems, changing water quantity and quality, food provisioning, recreational opportunities and transportation. Future research opportunities, including enhanced observation of lake variables from space (particularly for small water bodies), improved in situ lake monitoring and the development of advanced modelling techniques to predict lake processes, will improve our global understanding of lake responses to a changing climate

Results of pancreaticoduodenectomy for ampullary carcinoma and analysis of prognostic factors for survival

BACKGROUND: Results of pancreaticoduodenectomy for ampullary carcinoma were evaluated, and prognostic factors for survival were analyzed. METHODS: During the period from 1984 to 1992 67 patients underwent subtotal or total pancreaticoduodenectomy for ampullary carcinoma. All clinicopathologic data and their influence on survival were studied. RESULTS: Subtotal pancreaticoduodenectomy was performed in 62 of 67 patients with a mortality of 6% and a morbidity of 65%; the remaining five patients underwent total pancreaticoduodenectomy. Intraabdominal infection was the most important complication. Resection margins were tumor free in 75% of 67 patients. The overall 5-year survival was 50%. Survival was significantly influenced by the involvement of resection margins. After resection with involved margins 5-year survival was 15% and 60% after resection with free margins (p <0.001). Tumor size, lymph node involvement, and differentiation grade had limited and not significant influence on survival. CONCLUSIONS: Subtotal pancreaticoduodenectomy is the type of resection of first choice for ampullary carcinoma. Involvement of resection margins was the strongest prognostic factor for survival. Patients with a tumor size larger than 2 cm, with lymph node involvement, or with a poorly differentiated tumor still had a 5-year survival rate greater than 40%. Patients with involved margins might be candidates for studies on adjuvant therap

Portal vein resection in patients undergoing pancreatoduodenectomy for carcinoma of the pancreatic head

Of 176 patients with carcinoma of the pancreatic head region 156 underwent standard pancreatoduodenectomy (group 2) and 20 with macroscopic suspicion of invasion of the portal vein or superior mesenteric vein (SMV) underwent pancreatoduodenectomy with partial resection of the portal vein or SMV (group 1). In 16 patients in group 1 end-to-end anastomosis was used for reconstruction of the vein. The morbidity rate in groups 1 and 2 was similar (55 versus 63 per cent). The hospital mortality rate was 15 per cent in group 1 and 7 per cent in group 2 (P = 0.22). Histological examination confirmed tumour invasion of the portal vein or SMV in ten patients in group 1. Invasion of the portal vein or SMV was significantly more frequent in patients with pancreatic cancer than in those with distal bile duct or ampullary carcinoma. Of the 20 patients in group 1 only three underwent curative resection with tumour-free margins. The median survival time after resection of the portal vein or SMV was 8 months; the 2-year survival rate was 19 per cent. Comparison of survival in group 1 with survival in subgroups of patients undergoing standard pancreatoduodenectomy, matched for all histological parameters, showed no significant difference. It is concluded that partial resection of the portal vein or SMV in patients undergoing pancreatoduodenectomy who are suspected of having tumour invasion of the portal vein or SMV does not improve either the rate of curative resection or surviva

Long-term survival after resection of proximal bile duct carcinoma (Klatskin tumors)

This retrospective study in 79 surgically treated patients with a proximal bile duct carcinoma revealed 12 patients with a median age of 59.5 years (range 21-73 years) who survived more than 5 years. These 12 patients were analyzed to identify specific patient characteristics for long-term survival. Fifteen patients died from postoperative complications and were excluded from this survival analysis. In relation with preoperative Bismuth classification, there were 3 (20%) long-term survivors of 15 patients with type I tumors and 9 (35%) long-term survivors of 26 patients with type II tumors. In the group of type III and IV tumors, there were no long-term survivors. Concerning the type of resection, 9 of 51 (18%) patients had long-term survival after local resection and 3 of 13 (23%) patients after local resection combined with hemihepatectomy. Complete tumor-free surgical specimen margins were found in only 4 of 64 cases (6%), among which only one patient survived more than 5 years. Negative proximal bile duct margins, absence of multifocality, and diploid tumors showed a significant correlation with long-term survival. There was no significant correlation between long-term survival and postoperative radiotherapy. Of the 12 long-term survivors, 5 died after 5 years: 2 had developed metastases and 1 a local recurrence; the other 2 died of a metastasis of an ovarian adenocarcinoma and cachexia, respectively. The remaining seven patients were still alive at the completion of this study. The mean survival of the 64 patients analyzed in this study (in which hospital mortality was excluded) was 33.7 months, with a median survival of 18.8 months. In conclusion, the preoperative Bismuth classification of the tumor, absence of multifocality, diploid-type tumors, and negative proximal bile duct margins at histopathologic examination were the only significant prognostic factors for long-term surviva

Brain abnormalities in a case of malonyl-CoA decarboxylase deficiency

Malonyl-CoA decarboxylase (MCD) deficiency is an extremely rare inborn error of metabolism that presents with metabolic acidosis, hypoglycemia, and/or cardiomyopathy. Patients also show neurological signs and symptoms that have been infrequently reported. We describe a girl with MCD deficiency, whose brain MRI shows white matter abnormalities and additionally diffuse pachygyria and periventricular heterotopia, consistent with a malformation of cortical development. MLYCD-gene sequence analysis shows normal genomic sequence but no messenger product, suggesting an abnormality of transcription regulation. Our patient has strikingly low appetite, which is interesting in the light of the proposed role of malonyl-CoA in the regulation of feeding control, but this remains to be confirmed in other patients. Considering the incomplete understanding of the role of metabolic pathways in brain development, patients with MCD deficiency should be evaluated with brain MRI and unexplained malformations of cortical development should be reason for metabolic screenin

Benign biliary strictures. Surgery or endoscopy?

OBJECTIVE: This study compared the results of surgery and endoscopy for benign biliary strictures in one institution, over the same period of time and with the same outcome definitions. SUMMARY BACKGROUND DATA: Surgery is considered the treatment of choice, offering more than 80% long-term success. Endoscopic stenting has been reported to yield similar results and might be a useful alternative. METHODS: In this nonrandomized retrospective study, 101 patients with benign biliary strictures were included. Thirty-five patients were treated surgically and 66 by endoscopic stenting. Patient characteristics, initial trauma, previous repairs, and level of obstruction were comparable in both groups. Surgical therapy consisted of constructing a biliary-digestive anastomosis in normal ductal tissue. Endoscopic therapy consisted of placement of endoprostheses, with trimonthly elective exchange for a 1-year period. RESULTS: Mean length of follow-up was 50 +/- 3.8 and 42 +/- 4.2 months for surgery and endoscopy, respectively. Early complications occurred more frequently in the surgically treated group (p < 0.03). Late complications during therapy, occurred only in the endoscopically treated group. In 46 patients, the endoprostheses were eventually removed. Recurrent stricturing occurred in 17% in both surgical and endoscopic patients. CONCLUSIONS: Surgery and endoscopy for benign biliary strictures have similar long-term success rates. Indications for surgery are complete transections, failed previous repairs, and failures of endoscopic therapy. All other patients are candidates for endoscopic stenting as the initial treatment

Prevention of hepatic encephalopathy by administration of rifaximin and lactulose in patients with liver cirrhosis undergoing placement of a transjugular intrahepatic portosystemic shunt (TIPS): A multicentre randomised, double blind, placebo controlled trial (PEARL trial)

Introduction Cirrhotic patients with portal hypertension can suffer from variceal bleeding or refractory ascites and can benefit from a transjugular intrahepatic portosystemic shunt (TIPS). Post-TIPS hepatic encephalopathy (HE) is a common (20%-54%) and often severe complication. A prophylactic strategy is lacking. Methods and analysis The Prevention of hepatic Encephalopathy by Administration of Rifaximin and Lactulose in patients with liver cirrhosis undergoing placement of a TIPS (PEARL) trial, is a multicentre randomised, double blind, placebo controlled trial. Patients undergoing covered TIPS placement are prescribed either rifaximin 550 mg two times per day and lactulose 25 mL two times per day (starting dose) or placebo 550 mg two times per day and lactulose 25 mL two times per day from 72 hours before and until 3 months after TIPS placement. Primary endpoint is the development of overt HE (OHE) within 3 months (according to West Haven criteria). Secondary endpoints include 90-day mortality; development of a second episode of OHE; time to development of episode(s) of OHE; development of minimal HE; molecular changes in peripheral and portal blood samples; quality of life and cost-effectiveness. The total sample size is 238 patients and recruitment period is 3 years in six hospitals in the Netherlands and one in Belgium. Ethics and dissemination This study protocol was approved in the Netherlands by the Medical Research Ethics Committee of the Academic Medical Centre, Amsterdam (2018-332), in Belgium by the Ethics Committee Research UZ/KU Leuven (S62577) and competent authorities. This study will be conducted in accordance with Good Clinical Practice guidelines and the principles of the Declaration of Helsinki. Study results will be submitted for publication in a peer-reviewed journal. Trial registration numbers ClinicalTrials.gov (NCT04073290) and EudraCT database (2018-004323-37)