Osteonecrosis múltiple inducida por glucocorticoides / Multiple osteonecrosis induced bye glucocorticoids / Osteonecrose múltipla induzida por glicocorticóides

La osteonecrosis múltiple es una entidad poco frecuente que se define por el compromiso de al menos tres regiones diferentes. Es indispensable el abordaje multidisciplinario de los pacientes que la padecen tanto para el diagnóstico como el tratamiento oportuno. Presentamos el caso clínico de un paciente joven que presenta una osteonecrosis múltiple con compromiso de ambas caderas, hombros, rodillas, codo derecho y cuello de pie izquierdo. El principal factor de riesgo presente en nuestro caso es el consumo de glucocorticoides.

Multiple osteonecrosis is a rare entity that is defined by the involvement of at least three different regions. A multidisciplinary approach to patients who suffer from it is essential for both diagnosis and timely treatment. We present the clinical case of a young patient who presented multiple osteonecrosis with involvement of both hips, shoulders, knees, right elbow, and neck of the left foot. The main risk factor present in our case is the consumption of glucocorticoids.

A osteonecrose múltipla é uma entidade rara que se define pelo envolvimento de pelo menos três regiões diferentes. Uma abordagem multidisciplinar aos pacientes que sofrem com isso é essencial para o diagnóstico e tratamento oportuno. Apresentamos o caso clínico de um paciente jovem que apresenta osteonecrose múltipla envolvendo quadris, ombros, joelhos, cotovelo direito e pescoço do pé esquerdo. O principal fator de risco presente no nosso caso é o consumo de glicocorticóides.

El papel del cirujano moderno como líder de los equipos de atención sanitaria: una revisión narrativa sobre una facultad ubicua, pero poco definida.

OBJECTIVE: The objective is to describe the role of leadership in the training of the general surgeon and to point out its relevance. METHOD: A search of the medical literature was carried out to identify studies that reported on topics related to leadership in the context of medical education and surgery. We used the search engine of Medline/PubMed databases including related terms such as "leadership" AND "medicine" OR "surgery". RESULTS: Leadership is a valued characteristic in surgery, it implies professionalism, technical competence, motivation, innovation, teamwork, communication skills, decision making, emotional competence, resilience, and effective teaching. Leadership is measurable and can be developed through experience, observation, and education. CONCLUSIONS: Priority must be given to actions that improve leader traits. This has been shown to create a work environment where efficient work is performed, and failures are minimized. The current vision of the leader must be expanded to reduce the gender gap between the positions as leader occupy in this moment.

OBJETIVO: Describir el papel de liderazgo en la formación del cirujano general y puntualizar su relevancia en nuestro entorno. MÉTODO: Se realizó una búsqueda en la literatura médica para identificar estudios que informaran sobre temas relacionados al liderazgo en el contexto de la enseñanza médica y en cirugía. Se utilizó el motor de búsqueda de las bases de datos Medline/PubMed incluyendo términos relacionados como "leadership" AND "medicine" OR "surgery". RESULTADOS: El liderazgo es una característica valorada en cirugía, que implica profesionalismo, competencia técnica, motivación, innovación, trabajo en equipo, habilidades comunicativas, toma de decisiones, competencia emocional, resiliencia y enseñanza eficaz. Es medible y susceptible de desarrollarse a través de la experiencia, la observación y la educación. CONCLUSIONES: En la formación del cirujano general se deben priorizar las acciones que mejoren los rasgos de líder. Se ha demostrado que esto genera un ambiente de trabajo donde se realiza una labor eficiente y se minimizan las fallas. Se debe expandir la visión actual que se tiene de líder y permitir que se disminuya la brecha de género entre los puestos que hoy se ocupan.

Reporte de caso: vólvulo de sigmoides en un adulto joven, una manifestación de enfermedad de Hirschsprung.

BACKGROUND: Hirschsprung's disease is characterized by the absence of enteric ganglia in the distal digestive tract; being usually diagnosed in neonates, it rarely debuts during adulthood, where it presents as chronic constipation refractory to treatment. CASE REPORT: 24-year-old female patient with Hirschsprung's disease who arrives to the emergency room with a sigmoid volvulus requiring urgent surgical therapy. CONCLUSIONS: Hirschsprung's disease doesn't frequently debut in adulthood, presenting a diagnostic and therapeutic challenge for the general surgeon, especially when dealing with its complications.

ANTECEDENTES: La enfermedad de Hirschsprung se caracteriza por un defecto de las células nerviosas en el intestino distal. Suele diagnosticarse durante los primeros años de vida, rara vez debutando en adultos, en quienes se manifiesta como una constipación crónica refractaria al tratamiento. CASO CLÍNICO: Mujer de 24 años con enfermedad de Hirschsprung no diagnosticada, quien acude a urgencias por un cuadro de vólvulo de sigmoides que requiere intervención quirúrgica. CONCLUSIONES: La enfermedad de Hirschsprung rara vez debuta en la edad adulta y generalmente se diagnostica secundaria a sus complicaciones, por lo que supone un reto diagnóstico y terapéutico para el cirujano general.

High Dose Ascorbic Acid During Acute Resuscitation in Critically Burn Patients.

Ascorbic acid (AA) is a potent oxygen-free radical scavenger. We hypothesized that treating severe burn patients with high doses of AA (HDAA) can reduce fluid resuscitation requirements and prevent organ dysfunction. We performed a unicentric, retrospective case-control study of 75 burn patients: 25 patients admitted from 2018 to 2019 with more than 30% Total Surface Body Surface Area (TSBA) burned who received HDAA (66 mg/kg/h as soon as possible after admission until 36 h after injury), and 50 patients admitted from 2014 to 2017 with similar Abbreviated Burn Severity Index (ABSI)/Baux scores who were treated with the same protocol but did not receive HDAA. During the first 24 hours of burn resuscitation the HDAA group required less fluids than the control group (3.06 ± 0.87 ml/kg/%TBSA vs 4.32 ± 1.51 P < .05), but the overall reduction of fluid requirements during the first 72 hours was not significant. There were no significant differences in Sequential Organ Failure Assessment (SOFA), other hemodynamic parameters, complications, or mortality. We also did not find an increase acute kidney injury in patients who received HDAA even though the mean urine oxalate/creatinine ratio was 0.61 (0.02-0.96). We conclude that in severe burn patients treated with a restrictive fluid therapy protocol, administration of HDAA can decrease only the initial fluid requirements but not total fluid intakes. We did not find differences in severity score after resuscitation or in mortality. Nor did we find an increase in renal failure in patients administered with HDAA.

Perforated Jejunal Adenocarcinoma in a COVID-19-Positive Patient* / Adenocarcinoma jejunal perfurado em paciente positivo para covid-19

Abstract Jejunal adenocarcinoma is a rare type of primary small bowelmalignancy. It is generally diagnosed at late stages and as a surgical finding, with abdominal pain or discomfort being the main associated symptom. Cases presenting with perforation are even rarer, especially without disseminated disease. The relationship between cancer and coronavirus disease 2019 (COVID-19) is still being studied, as well as the postsurgical evolution of COVID-19 patients and its possible causality of intestinal perforation. We present the case of a perforated jejunal adenocarcinoma in a COVID-19-positive patient, in whom the symptomatology secondary to the perforation led to an early diagnosis, treatment and adequate postsurgical evolution, despite the concomitant condition.

Resumo O adenocarcinoma jejunal é um tipo raro de malignidade primária do intestino delgado, o qual geralmente é diagnosticado em estágios tardios e como achado cirúrgico, sendo a dor ou o desconforto abdominal o principal sintoma associado. Casos que apresentam perfuração são ainda mais raros, principalmente sem doença disseminada. A relação entre câncer e a cornonavirus disease 2019 (covid-19) ainda está sendo estudada, assim como a evolução pós-cirúrgica de pacientes com covid-19 e sua possível causalidade de perfuração intestinal. Apresentamos o caso de um adenocarcinoma jejunal perfurado em um paciente positivo para covid-19, em que a sintomatologia secundária à perfuração levou a um diagnóstico precoce, tratamento e evolução pós-cirúrgica adequada, apesar da condição concomitante.

Clinical Features and Computed Tomography Findings Are Utilized to Characterize Retrobulbar Disease in Dogs.

The objective of this study is to describe the clinical features and computed tomography (CT) findings of dogs with retrobulbar disease. There are two facets to this study: a retrospective case series in which findings of dogs with primary vs. secondary retrobulbar disease are described, and a retrospective cross-sectional study in which computed tomography findings of dogs with retrobulbar neoplasia vs. infection/inflammation are described and compared. The medical records of 66 client-owned dogs diagnosed with retrobulbar disease between 2006 and 2016 were reviewed. Clinical information including signalment, the specialty service to which the dog was presented, clinical signs, physical examination findings, diagnostic results, treatment, and outcome were documented. Diagnostic imaging and histopathology were reviewed. Forty-one dogs (62.1%) were diagnosed with primary disease of the retrobulbar space; 25 dogs (37.9%) were considered to have secondary retrobulbar disease. Of the 41 dogs with primary retrobulbar disease, 19 were diagnosed with neoplasia, 19 with infectious/inflammatory disease, and 3 suffered traumatic insult to the retrobulbar space. Of the 25 dogs with secondary retrobulbar disease, 21 were diagnosed with neoplasia, 3 with infectious/inflammatory disease, and 1 with a cyst. Dogs had a combination of ocular, oral, and/or nasal clinical signs. CT findings of orbital osteolysis, orbital periosteal reaction, and presence of a retrobulbar mass were significantly associated with neoplasia, while zygomatic salivary gland enlargement, retrobulbar mass effect, and mandibular lymphadenopathy were more often associated with infectious/inflammatory disease. CT findings overlap among different retrobulbar diseases, but new bone formation and lysis are more often associated with neoplasia. Disease originating from the retrobulbar space was equally likely to be infectious/inflammatory (n = 19) or neoplastic (n = 19), based on definitive diagnostic results of dogs with primary retrobulbar disease. Due to the clinical ramifications of these disorders, the diagnosis and treatment of these cases should be managed with a multi-specialty approach.

Non-covalent interactions at electrochemical interfaces: one model fits all?

The shift with increasing concentration of alkali-metal cations of the potentials of both the spike and the hump observed in the cyclic voltammograms of Pt(111) electrodes in sulfuric acid solutions is shown to obey the simple model recently developed by us to explain the effect of non-covalent interactions at the electrical double layer. The results suggest that the model, originally developed to describe the effect of alkali-metal cations on the cyclic voltammogram of cyanide-modified Pt(111) electrodes, is of general applicability and can explain quantitatively the effect of cations on the properties of the electrical double layer.

Adsorbed formate: the key intermediate in the oxidation of formic acid on platinum electrodes.

The electrooxidation of formic acid on Pt and other noble metal electrodes proceeds through a dual-path mechanism, composed of a direct path and an indirect path through adsorbed carbon monoxide, a poisoning intermediate. Adsorbed formate had been identified as the reactive intermediate in the direct path. Here we show that actually it is also the intermediate in the indirect path and is, hence, the key reaction intermediate, common to both the direct and indirect paths. Furthermore, it is confirmed that the dehydration of formic acid on Pt electrodes requires adjacent empty sites, and it is demonstrated that the reaction follows an apparently paradoxical electrochemical mechanism, in which an oxidation is immediately followed by a reduction.

Closure to efficient causation, computability and artificial life.

The major insight in Robert Rosen's view of a living organism as an (M,R)-system was the realization that an organism must be "closed to efficient causation", which means that the catalysts needed for its operation must be generated internally. This aspect is not controversial, but there has been confusion and misunderstanding about the logic Rosen used to achieve this closure. In addition, his corollary that an organism is not a mechanism and cannot have simulable models has led to much argument, most of it mathematical in nature and difficult to appreciate. Here we examine some of the mathematical arguments and clarify the conditions for closure.

Study by XPS and UV-visible and DRIFT spectroscopies of electropolymerized films of substituted Ni(II)-p-phenylporphyrins and -phthalocyanines.

Films of nickel tetrasulfophthalocyanine and - p-phenylporphyrin (NiTSPc and NiTSPP, respectively) were obtained by repetitive cyclic voltammetry (RCV) of the 1 mM complex in aqueous solution, while films of the water-insoluble nickel tetraaminophthalocyanine and - p-phenylporphyrin (NiTAPc and NiTAPP, respectively) had to be obtained by RCV of the 1 mM complex in organic solvents. Glassy carbon (GC), ITO, or platinum electrodes were used as substrates. The modified electrodes were characterized by cyclic voltammetry (CV) and UV-visible, infrared, and X-ray photoelectron spectroscopies. The CVs of the sulfo films showed the characteristic peaks of the Ni(II)/Ni(III) process, whereas the CVs of the amino films did not, very small Ni(II)/Ni(III) peaks appearing only after activation by RCV. Upon oxidation to Ni(III) both sulfo films changed from transparent to dark violet. The IR spectra of the polyNiTSPP and the polyNiTSPc films showed bands at 3628 cm (-1) and 3500 cm (-1), respectively, which could be due to interstitial water molecules occluded during the polymerization. The Ni 2p XP spectra indicate that the magnetic character of the Ni(II) ions in NiTSPP is dramatically changed by the polymerization, from diamagnetic in the monomer to paramagnetic in the polymeric film, indicating the formation of Ni-O-Ni bridges or of clusters of Ni(OH) 2. On the contrary, the Ni 2p XP spectra of the unactivated NiTAPP film, in which the Ni(II)/Ni(III) process was absent, showed only diamagnetic Ni(II). Therefore, it is concluded that only paramagnetic Ni(II) ions can be electrooxidized to Ni(III).

Forjadores de la ciencia en Chile: problemas y soluciones / Forgers of the science in Chile: problems and solutions

La forma tradicional de pensar el pasado ha llevado a que, muchas veces, tienda a creerse que no han existido grandes científicos en Chile. Nuestra historia nombra políticos, militares, escritores, publicitas empresarios, artistas: rara vez un científico o una experiência científica. Este libro quiere demostrar lo contrario. Existe un largo camino recorido por la ciencia y de allí se desprende el nombre de hombres y mujeres que, con su esfuerzo y talento, han aportado al progreso del conocimieno y el desarrollo del país, unas veces anticipando teorías e invenciones y otras resolviendo problemas contingentes. El objetivo final de los autores es contribuir a forma conciencia sobre las características de nuestro patrimonio científico y a la vez mostrar las dificuldades, triunfos y fracasos de las personas que se han dedicado a la ciencia en Chile. [AU]

Fray Pedro Manuel Chaparro: la lucha contra la viruela / Friar Pedro Manuel Chaparro: the combat against the smallpox

La viruela fue una cruel enfermedad que asoló la humanidad desde tiempos inmemoriales. En el último milenio fue una de las enfermedades más comunes de europa, donde epidemias de viruela azotaban ciudades y regiones enteras, poduciendo pánico y muerte, especialmente en la población infantil. De europa pasó a Latinoamérica en tiempos de la conquista. [AU]

Manuel Antonio Carmona: ciencia y enfermedades mentales / Manuel Antonio Carmona: science and mentals diseases

Las pertubaciones mentales han acompañado a la humanidad desde siempre. en la europa de los siglos XVI y XVII, los locos eran considerados como poseídos por el demonio y existían manuales sobre los medios para expulsar a este del cuerpo de los poseídos. En muchos casos la única solución era quemar al poseído, como a las brujas, en la hoguera. Quienes padecían pertubaciones mentales no eran considerado enfermos, y por conseguinte no eran tratados por médicos ni especialistas, sino por sacerdotes e inquisitores. Quienes no eran consideados 'normales' eran confinados en asilos donde eran torturados y tratados con esposas, cadenas de hierro y cepos. Esto duró al menos hasta fines del siglo XVIII. Por esta época comenzaron a surgir voces que hipotetizaban algún desorden mental y sugerían tratarlos de menera distinta de los vagabundos, delincuentes y malhechores. Unrol importante en esta campaña lo jugaron dos filantropistas, Phillipe Pinel quien desafió arbiertatamene a los revolucionarios franceses que paradójicamente no veían esta otra opresión; y William Tuke, un cuáquero inglés que fundó una sociedad de ayuda y un establecimiento para dementes ubicado 'en el medio de una campiña fértil y risueña; no sugiere en absoluto la idea de una prisión, sino más bien de una gran granja; está rodeada por un grandioso y amurallado jardín. [AU]

Salazar y Zegers: los rayos x / Salazar and Zegers: X-rays

La gran revolución de la física ocurrida a comienzos del siglo XX fue posible gracias a las bases sentadas en esta disciplina en la segunda mitad del siglo anterior: Una cobinación de avanzada experimentación y teoría con aplicaciones práticas muy exitoras, todo edificado sobre la sólida base de la mecánica clásica. Los resultados de Faraday y Maxwell en electromagnestismo se aplicaban a fuentes de energía y luz elétrica y abrían el camino para la comunicación inalámbrica. La termodinámica, que había permitido la construcción del motor de combustión interna, comenzaba a influir en el diseño de fuentes de calor y plantas químicas. Sin embargo, el punto de quiebre en el conocimiento lo iban a producir otras áreas de la física, entre las cuales destaca la de los fenómenos asociados a las descargas elétricas, que no tenían explicación en términos de la física clásica. En efecto, gracias a experimentos en tubos de descarga se logró, entre otros, el descubriemiento de los rayos X y el electrón, dos hechos fundamentales para el nacimiento de la física del micromundo, la física cuántica. [AU]

Forjadores de la ciencia en Chile: problemas y soluciones / Forgers of the science in Chile: problems and solutions

La forma tradicional de pensar el pasado ha llevado a que, muchas veces, tienda a creerse que no han existido grandes científicos en Chile. Nuestra historia nombra políticos, militares, escritores, publicitas empresarios, artistas: rara vez un científico o una experiência científica. Este libro quiere demostrar lo contrario. Existe un largo camino recorido por la ciencia y de allí se desprende el nombre de hombres y mujeres que, con su esfuerzo y talento, han aportado al progreso del conocimieno y el desarrollo del país, unas veces anticipando teorías e invenciones y otras resolviendo problemas contingentes. El objetivo final de los autores es contribuir a forma conciencia sobre las características de nuestro patrimonio científico y a la vez mostrar las dificuldades, triunfos y fracasos de las personas que se han dedicado a la ciencia en Chile.

Fray Pedro Manuel Chaparro: la lucha contra la viruela / Friar Pedro Manuel Chaparro: the combat against the smallpox

La viruela fue una cruel enfermedad que asoló la humanidad desde tiempos inmemoriales. En el último milenio fue una de las enfermedades más comunes de Europa, donde epidemias de viruela azotaban ciudades y regiones enteras, poduciendo pánico y muerte, especialmente en la población infantil. De europa pasó a Latinoamérica en tiempos de la conquista.