The OpenMolcas Web: A Community-Driven Approach to Advancing Computational Chemistry

The developments of the open-source OpenMolcas chemistry software environment since spring 2020 are described, with a focus on novel functionalities accessible in the stable branch of the package or via interfaces with other packages. These developments span a wide range of topics in computational chemistry and are presented in thematic sections: electronic structure theory, electronic spectroscopy simulations, analytic gradients and molecular structure optimizations, ab initio molecular dynamics, and other new features. This report offers an overview of the chemical phenomena and processes OpenMolcas can address, while showing that OpenMolcas is an attractive platform for state-of-the-art atomistic computer simulations

Abnormal plasma polyunsaturated fatty acid pattern in non-active inflammatory bowel disease

An abnormal plasma polyunsaturated fatty acid pattern (PUFA) (increased n3 and decreased n6 PUFA) has been reported in active inflammatory bowel disease (IBD). The possibility of a primary defect in the PUFA metabolism in IBD was hypothesised. The aim of this study was to assess plasma PUFA pattern in inactive inflammatory bowel disease and to ascertain whether patients who had had a colectomy and who were suffering from ulcerative colitis have a similar PUFA pattern than those patients with non-active ulcerative colitis and who had not had a colectomy. Plasma fatty acids were analysed by semi-capillary column gas-liquid chromatography in three groups of patients with inactive IBD (24 patients with inactive ulcerative colitis who had not had a colectomy, 15 patients with ulcerative colitis who had had a colectomy, and 27 patients with Crohn's disease). Plasma concentration and percentage of C22:6n3 and unsaturation index were significantly higher in patients with inactive ulcerative colitis without a colectomy and the Crohn's disease group (p < 0.0001) than in controls. Plasma concentration and percentage of C22:6n3 and the unsaturation index remained significantly higher, in both the operated and non-operated ulcerative colitis patients when compared with controls (p < 0.0001). These results suggest that in inactive IBD, an increased PUFA biosynthesis might be the cause of the high values of n3 compounds. These findings although seen in active disease, are more noticeable in remission because of the lack of artefactual factors (malnutrition, steroids, inflammation). In addition, persistence of high values in both groups of ulcerative colitis patients--that is, those who had had a colectomy and those who had not suggests the existence of a primary abnormality in the PUFA metabolism in IBD

Antineutrophil cytoplasmic antibodies in sera from colectomised ulcerative colitis patients and its relation to the presence of pouchitis.

BACKGROUND: Few studies have evaluated the influence of colectomy on antineutrophil cytoplasmic antibody (ANCA) positivity in ulcerative colitis (UC). In small series of patients it has been suggested that ANCA positivity in UC might be predictive for development of pouchitis after colectomy. AIMS: To assess the prevalence of ANCA in UC patients treated by colectomy and a Brooke's ileostomy (UC-BI) or ileal pouch anal anastomosis (UC-IPAA), and the relation between the presence of ANCA, the type of surgery, and the presence of pouchitis. SUBJECTS: 63 UC patients treated by colectomy (32 with UC-BI and 31 with UC-IPAA), 54 UC, and 24 controls. METHODS: Samples were obtained at least two years after colectomy. ANCA were detected by indirect immunofluorescent assay. RESULTS: There were no differences between patients with (36.3%) or without pouchitis (35.0%) and between patients with UC (55%), UC-BI (40.6%), and UC-IPAA (35.4%). However, ANCA prevalence significantly decreases in the whole group of operated patients (38.0%) compared with non-operated UC (p = 0.044). CONCLUSIONS: The prevalence of ANCA in operated patients was significantly lower than in non-operated UC, suggesting that it might be related either to the presence of inflamed or diseased tissue. ANCA persistence is not related to the surgical procedure and it should not be used as a marker for predicting the development of pouchitis

A novel lumen-apposing metal stent for endoscopic ultrasound-guided drainage of pancreatic fluid collections: a prospective cohort study

BACKGROUND AND STUDY AIMS: A novel large-diameter, lumen-apposing, self-expanding metal stent with bilateral flanges was recently developed for endoscopic ultrasound (EUS)-guided transmural drainage of symptomatic pancreatic fluid collections (PFCs). The aim of this study was to evaluate the efficacy and safety of this stent in a large cohort. PATIENTS AND METHODS: Patients with a PFC undergoing EUS-guided drainage with this novel stent were prospectively enrolled in this multicenter cohort study. RESULTS: There were 61 patients: 46 patients (75 %) with walled-off necrosis (WON) and 15 (25 %) with a pancreatic pseudocyst. Stent placement was technically successful in 60 patients (98 %, 95 %CI 95 % - 100 %). Clinical success, defined as resolution of clinical symptoms in combination with a decrease in the PFC size to </= 2 cm on imaging, was achieved in 93 % of patients with a pancreatic pseudocyst (95 %CI 77 % - 100 %) and in 81 % of patients with WON (95 %CI 69 % - 94 %). Treatment failure occurred in nine patients (16 %, 95 %CI 6 % - 26 %), including four patients who required surgical intervention. Stent removal was performed in 82 % of patients after a median of 32 days (range 2 - 178) and was rated as easy in all but one patient. In 10 patients, endoscopic stent removal was not performed because of stent migration (n = 3), stent dislodgement during necrosectomy (n = 3), stent removal during surgery (n = 2), or refusal by the patient (n = 2). In total, five major complications were reported (9 %, 95 %CI 2 % - 16 %), including PFC infection (n = 4) and perforation (n = 1). CONCLUSION: EUS-guided drainage using this novel stent is feasible and the clinical results obtained are promising with a low major complication rate