Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

: The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

Evaluation of appendicitis risk prediction models in adults with suspected appendicitis

Background Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis. Methods A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis). Results Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent). Conclusion Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified

Competing thermal electrocyclic ring-closure reactions of (2Z)-hexa-2,4,5-trienals and their Schiff bases. Structural, kinetic, and computational studies

10 pags., 6 figs., 2 tabs., 3 schs. -- This paper is dedicated to Prof. Pelayo Camps(University of Barcelona)onthe occasion of his 65th birthday.The electrocyclic ring closure reactions of (2Z)-hexa-2,4,5-trienals (vinylallenals) to alkylidene-2H-pyrans and of the corresponding Schiff base derivatives to alkylidenepyridines can be concurrent. Rates of vinylallenal cyclization and imine formation upon addition of n-butylamine determine the extent of the competition. The activation energies for the electrocyclization of a series of 6-substituted-(2Z)-4-tert-butyl-3-methylhexa-2,4,5-trienals 2 and trienimines 4 depend on the steric interactions between the substituents at C6 and the tert-butyl group at C4. Mixtures of alkylidene-2H-pyrans 3 and alkylidenepyridines 5 are obtained with bulky groups at C6, whereas only the latter is obtained with a C6-t-Bu and only the former with substituents of moderate size at C6. The reaction rates were indirectly derived from the empirical observations using a global optimization study based on differential evolution. The cyclizations are torquoselective, and the kinetically favored (E)-alkylidene heterocycles evolve by electrocyclic ring opening/ring closure toward the thermodynamic Z isomers upon extended reaction times. Density functional theory (DFT) calculations of the electrocyclizations helped in their characterization as monorotatory processes with pseudopericyclic features and made it possible to rationalize the reactivity trends and the torquoselectivity.The authors are grateful to the European Union (EPITRON, IP-LSCH-CT-2005-518417), the MEC-Spain (SAF2007-63880-FEDER, FPI Contract to J.A.S.), Xunta de Galicia (Parga Pondal Contract to C.S.L.and M.P.R.; Grant 08CSA052383PR from DX IþDþi;Consolidaci on 2006/15 from DXPCTSUG) for financialsupport and the Centro de Supercomputaci on de Galicia(CESGA) for generous allocation of computer time.Peer reviewe

Palaeoenvironmental use of silicophytoliths in soils and palaeosols associated with Holocene volcanic ash deposits in north-western Argentina

We compare the silicophytolith record of current soils and Holocene palaeosols from two sedimentary sequences in a region between the Chaco-Pampean Plain and the Puna (Tolombón section in Santa María Valley, and Tafí del Valle section in Tafí Valley), NW Argentina. These two geographic areas are separated by the Aconquija-Cumbres Calchaquíes ranges, a climatic barrier to the wet Atlantic winds. These sequences contain volcanic ash deposits recording two large eruptions occurred during Holocene in the Southern Puna in the Central Volcanic Zone of the Andes, from the Cueros de Purulla volcano (ca. 7820 BP) and the Cerro Blanco Volcanic Complex (ca. 4200 cal BP). These ash-fall deposits buried soils and preserved their silicophytolith record, allowing the use of this palaeoenvironmental proxy to clarify the vegetation prior these two volcanic events. The silicophytolith assemblages yield evidence for a mega/mesothermal xerophytic grassland when Tolombón palaeosol was formed, similar to the present-day environment in the Santa María Valley, with presence of C4 grasses (Chloridoideae and Panicoidae). Instead, the climate was cooler and wetter ca. 4200 cal BP than currently in the Tafí Valley, increasing over time aridity and abundance of C4 grasses (Chloridoidae, Panicoideae), and decreasing the quantity of C3 grasses (Pooideae). Prehistorical and historical land use also contributed to this change. The impact of these large volcanic ash-falls on vegetation did not translate in an abrupt change on phytodiversity. Results point out a stable arid environment during Holocene in the Santa María Valley whereas the Tafí Valley was more sensitive to environmental changes due to its location in the eastern slopes of Aconquija-Cumbres Calchaquíes ranges, more exposed to the wet Atlantic winds.MINECO, Spain, CGL2011-23307, Project QUECA Agencia-Ministerio de Ciencia y Técnica, Argentina, PICT-1583-2013 Universidad Nacional de Mar del Plata, EXA 643/13 Canary Islands Government, ULPGC, Research Consolidated Group GEOVOL Generalitat de Catalunya, 2017 SGR 1494, Research Consolidated Group GEOPAMPeer reviewe

Molecular background, clinical features and management of pediatric mastocytosis: Status 2021

Pediatric mastocytosis is a heterogeneous disease characterized by accumulation of mast cells in the skin and less frequently in other organs. Somatic or germline mutations in the KIT proto-oncogene are detected in most patients. Cutaneous mastocytosis is the most common form of the disease in children. In the majority of cases, skin lesions regress spontaneously around puberty. However, in few patients, mastocytosis is not a self\u2010limiting disease, but persists into adulthood and can show signs of systemic involvement, especially when skin lesions are small\u2010sized and monomorphic. Children with mastocytosis often suffer from mast cell mediator\u2010related symptoms. Severe hypersensitivity reactions can also occur, mostly in patients with extensive skin lesions and blistering. In a substantial number of these cases, the triggering factor of anaphylaxis remains unidentified. Management of pediatric mastocytosis is mainly based on strict avoidance of triggers, treatment with H1 and H2 histamine receptor blockers, and equipment of patients and their families with epinephrine auto\u2010injectors for use in severe anaphylactic reactions. Advanced systemic mastocytosis occurs occasionally. All children with mastocytosis require follow\u2010up examinations. A bone marrow investigation is performed when advanced systemic mastocytosis is suspected and has an impact on therapy or when cutaneous disease persists into adulthood