Resultados de la cirugía de sustitución esofágica con tubo gástrico invertido vía ascenso retroesternal en dos hospitales pediátricos / Results of esophageal substitution surgery with inverted gastric tube via retrosternal lift

Resumen Objetivo: Describir resultados de la cirugía de sustitución esofágica con tubo gástrico invertido, vía ascenso retroesternal en dos hospitales pediátricos durante el período marzo 2015 a marzo 2018. Materiales y Método: Un estudio observacional, transversal, con recolección de datos retrospectivo, donde se incluyeron todos los expedientes de pacientes que presentaban patología del esófago por causa adquirida o congénita que fueron operados de sustitución esofágica con tubo gástrico invertido en dos hospitales pediátricos durante 3 años. Resultados: Encontramos 29 niños sometidos a sustitución esofágica, de los cuales 27 cumplieron criterios de inclusión. La edad comprendida entre 2 y 17 años. El 63% corresponde al sexo femenino. La causa más frecuente de sustitución esofágica es por estenosis esofágica por ingesta caustica (92,59%). El 70% presentó algún tipo de complicación luego de la cirugía. La fístula esofagocutánea es la complicación principal con 33,33%. La permanencia en la unidad de cuidados intensivos es menor de 24 horas en un 74% de los niños. Se inicia la vía oral en casi la mitad de casos entre los 10-12 días de posquirúrgico, la estancia hospitalaria es en promedio 18,5 días. La mortalidad es 3,7%. Conclusión: La sustitución esofágica por tubo gástrico invertido vía ascenso retroesternal, es una técnica comparable en resultados a la interposición de colón. Para los autores, el estómago es un órgano ideal para realizar la reconstrucción esofágica, y sus complicaciones son manejables.

Aim: To describe the results of esophageal replacement surgery with an inverted gastric tube via retrosternal ascent in two pediatric hospitals during the period March 2015 to March 2018. Materials and Method: an observational, cross-sectional study with retrospective data collection that included all the records of patients with esophageal discontinuity due to acquired or congenital causes who underwent esophageal replacement surgery with an inverted gastric tube in two pediatric hospitals for 3 years. Results: We found 29 children undergoing esophageal replacement, of which 27 met inclusion criteria. The age between 2 to 17 years. 63% corresponds to the female sex. The most frequent cause of esophageal replacement is esophageal stricture due to caustic ingestion (92.59%). 70% presented some type of complication after surgery. The esophagocutaneous fistula is the main complication with 33.33%. The stay in the intensive care unit is less than 24 hours in 74% of children. The oral route is started in almost half of cases between 10-12 days after surgery; the hospital stay is on average 18.5 days. Mortality is 3.70%. Conclusión: The esophageal substitution by inverted gastric tube via retrosternal ascent is a technique comparable in results to the interposition of the colon. For the authors, the stomach is an ideal organ to perform esophageal reconstruction, and its complications are manageable.

Calcium Oxalate Crystals in Leaves of the Extremophile Plant Colobanthus quitensis (Kunth) Bartl. (Caryophyllaceae).

The presence of calcium oxalate (CaOx) crystals has been widely reported in the plant kingdom. These structures play a central role in various physiological functions, including calcium regulation, metal detoxification, and photosynthesis. However, precise knowledge about their possible roles and functions in plants is still limited. Therefore, the present work aims to study the ecotypic variability of Colobanthus quitensis, an extremophile species, concerning CaOx crystal accumulation. The CaOx crystals were studied in leaves of C. quitensis collected from different provenances within a latitudinal gradient (From Andes mountains in central Chile to Antarctica) and grown under common garden conditions. Polarized light microscopy, digital image analysis, and electron microscopy were used to characterize CaOx crystals. The presence of CaOx crystals was confirmed in the four provenances of C. quitensis, with significant differences in the accumulation among them. The Andean populations presented the highest accumulation of crystals and the Antarctic population the lowest. Electron microscopy showed that CaOx crystals in C. quitensis are classified as druses based on their morphology. The differences found could be linked to processes of ecotypic differentiation and plant adaptation to harsh environments.

Continuous flow synthesis of arylhydrazines via nickel/photoredox coupling of tert-butyl carbazate with aryl halides.

Nickel/photoredox catalyzed C-N couplings of hydrazine-derived nucleophiles provide a powerful alternative to Pd-catalyzed methods. This continuous-flow photochemical protocol, optimized using design of experiments, achieves these couplings in short residence times, with high selectivity. A range of (hetero)aryl bromides and chlorides are compatible and understanding of process stability/reactor fouling has been discerned.

Morphological variation of the early human remains from Quintana Roo, Yucatán Peninsula, Mexico: Contributions to the discussions about the settlement of the Americas.

The human settlement of the Americas has been a topic of intense debate for centuries, and there is still no consensus on the tempo and mode of early human dispersion across the continent. When trying to explain the biological diversity of early groups across North, Central and South America, studies have defended a wide range of dispersion models that tend to oversimplify the diversity observed across the continent. In this study, we aim to contribute to this debate by exploring the cranial morphological affinities of four late Pleistocene/early Holocene specimens recovered from the caves of Quintana Roo, Mexico. The four specimens are among the earliest human remains known in the continent and permit the contextualization of biological diversity present during the initial millennia of human presence in the Americas. The specimens were compared to worldwide reference series through geometric morphometric analyses of 3D anatomical landmarks. Morphological data were analyzed through exploratory visual multivariate analyses and multivariate classification based on Mahalanobis distances. The results show very different patterns of morphological association for each Quintana Roo specimen, suggesting that the early populations of the region already shared a high degree of morphological diversity. This contrasts with previous studies of South American remains and opens the possibility that the initial populations of North America already had a high level of morphological diversity, which was reduced as populations dispersed into the southern continent. As such, the study of these rare remains illustrates that we are probably still underestimating the biological diversity of early Americans.

Continuous-Flow Pd-Catalyzed Carbonylation of Aryl Chlorides with Carbon Monoxide at Elevated Temperature and Pressure.

The development of a continuous-flow protocol for a palladium-catalyzed methoxycarbonylation of (hetero)aryl chlorides using carbon monoxide gas and methanol is described. (Hetero)aryl chlorides are the least expensive of the aryl halides, but are underutilized in carbonylation reactions due to their very poor reactivity. The described protocol exploits intensified conditions at elevated temperature and pressure, which are readily accessed within a continuous-flow environment, to provide moderate to excellent product yields (11 examples) in a short 16 min residence time. The continuous-flow protocol enables the safe and potentially scalable carbonylation of aryl chlorides using CO gas.

Continuous-flow protocol for the synthesis of enantiomerically pure intermediates of anti epilepsy and anti tuberculosis active pharmaceutical ingredients.

Continuous-flow production of chiral intermediates plays an important role in the development of building blocks for Active Pharmaceutical Ingredients (APIs), being α-amino acids and their derivatives widely applied as building blocks. In this work we developed two different strategies for the synthesis of intermediates used on the synthesis of levetiracetam/brivaracetam and ethambutol. The results obtained show that methionine methyl ester can be continuously converted to the desired ethambutol intermediate by RANEY® Nickel dessulfurization/reduction strategy whereas levetiracetam/brivaracetam intermediates could be synthesized by both RANEY® Nickel (without H2) and Pd/C-H2 approach or by photochemical desulfurization.

The earliest settlers of Mesoamerica date back to the late Pleistocene.

Preceramic human skeletal remains preserved in submerged caves near Tulum in the Mexican state of Quintana Roo, Mexico, reveal conflicting results regarding 14C dating. Here we use U-series techniques for dating a stalagmite overgrowing the pelvis of a human skeleton discovered in the submerged Chan Hol cave. The oldest closed system U/Th age comes from around 21 mm above the pelvis defining the terminus ante quem for the pelvis to 11311±370 y BP. However, the skeleton might be considerable older, probably as old as 13 ky BP as indicated by the speleothem stable isotope data. The Chan Hol individual confirms a late Pleistocene settling of Mesoamerica and represents one of the oldest human osteological remains in America.

Synthesis and antimicrobial activity of tetradentate ligands bearing hydrazone and/or thiosemicarbazone motifs and their diorganotin(IV) complexes.

Four novel ligands derived from 2,3-butanedione have been synthesized, two dissymmetric thiosemicarbazone/3-hydroxy-2-naphthohydrazone ligands, H2L1 (bearing 4-isopropyl-3-thiosemicarbazone) and H2L2 (containing 4-cyclohexyl-3-thiosemicarbazone) and the symmetric H2L3, diacetyl bis(3-hydroxy-2-naphthohydrazone), and H2L4, diacetyl bis(4-cyclohexyl-3-thiosemicarbazone). Their reactivity with SnR2Cl2 (R=methyl, n-butyl and phenyl) was explored and the resulting complexes were characterized by elemental analysis, molar conductivity, mass spectrometry, IR, 1H, 13C and 119Sn NMR and seven of them also by single crystal X-ray diffraction. The results showed that the reactivity of the dissymmetric ligands is strongly different and while the cyclohexyl derivative is very stable, with isopropyl easily undergoes a symmetrization reaction to yield the corresponding symmetric ligands. The antimicrobial activity of the ligands and the corresponding diorganotin(IV) complexes was investigated in vitro against seven species of microorganisms and minimum inhibitory concentrations (MICs) were determined. The results showed that the ligand H2L2 and several of its derivatives, together with methyl and phenyl complexes of H2L1, have the ability of inhibiting the growth of tested bacteria and fungi to different extents. Bacillus subtilis and Staphylococcus aureus Gram positive strains were the most sensitive microorganisms.

All-inside suture technique using anterior portals in posterior horn tears of lateral meniscus.

Methods for the repair of meniscal tears include inside-out, outside-in, and all-inside techniques. In this article an all-inside technique is proposed for the posterior horn of the lateral meniscus that takes advantage of the capacious posterolateral recess when the knee is flexed. A device consisting of a large needle with a buttonhole in the tip (previously used for inside-out suture of the medial meniscus) is used. This technique uses only anterior portals (anteromedial and anterolateral portals and an accessory lateral or transpatellar tendon portal). The arthroscope is inserted through the accessory portal. Once the tear has been located and its edges refreshed, the suture device is placed anterolaterally. The tip of the needle is loaded with suture and passed through both sides of the tear and into the posterolateral recess of the knee (without exiting the capsule). The suture tail is recovered with the use of a suture retriever through the anteromedial portal. Next, the suture retriever is inserted through the anterolateral portal to once again retrieve and shuttle the tail before completion of an arthroscopic knot. In addition to the ease of the technique, use of this simple, reusable device adds the benefit of low cost when compared with other techniques.