Development and assessment of competency-based neurotrauma course curriculum for international neurosurgery residents and neurosurgeons.

OBJECTIVE: Traumatic brain injuries (TBIs) are a significant disease burden worldwide. It is imperative to improve neurosurgeons' training during and after their medical residency with appropriate neurotrauma competencies. Unfortunately, the development of these competencies during neurosurgeons' careers and in daily practice is very heterogeneous. This article aimed to describe the development and evaluation of a competency-based international course curriculum designed to address a broad spectrum of needs for taking care of patients with neurotrauma with basic and advanced interventions in different scenarios around the world. METHODS: A committee of 5 academic neurosurgeons was involved in the task of building this course curriculum. The process started with the identification of the problems to be addressed and the subsequent performance needed. After this, competencies were defined. In the final phase, educational activities were designed to achieve the intended learning outcomes. In the end, the entire process resulted in competency and outcomes-based education strategy, including a definition of all learning activities and learning outcomes (curriculum), that can be integrated with a faculty development process, including training. Further development was completed by 4 additional academic neurosurgeons supported by a curriculum developer specialist and a project manager. After the development of the course curriculum, template programs were developed with core and optional content defined for implementation and evaluation. RESULTS: The content of the course curriculum is divided into essentials and advanced concepts and interventions in neurotrauma care. A mixed sample of 1583 neurosurgeons and neurosurgery residents attending 36 continuing medical education activities in 30 different cities around the world evaluated the course. The average satisfaction was 97%. The average usefulness score was 4.2, according to the Likert scale. CONCLUSIONS: An international competency-based course curriculum is an option for creating a well-accepted neurotrauma educational process designed to address a broad spectrum of needs that a neurotrauma practitioner faces during the basic and advanced care of patients in different regions of the world. This process may also be applied to other areas of the neurosurgical knowledge spectrum. Moreover, this process allows worldwide standardization of knowledge requirements and competencies, such that training may be better benchmarked between countries regardless of their income level.

Late Oligocene-Miocene non-lunulate sand dollars of South America: Revision of abertellid taxa and descriptions of two new families, two new genera, and a new species.

Material for all seven South American species of late Oligocene and Miocene scutelliform, non-lunulate sand dollars (Echinoidea: Clypeasteroida) was examined, resulting in revision of several taxa, and description of a new family, Placatenellidae n. fam., to house Placatenella n. gen. and Camachoaster n. gen. Known only from the state of Pará, Brazil, and previously described as a member of Abertella Durham, 1953, A. complanata Brito, 1981 is redescribed on the basis of analysis of the holotype and subsequently described material from the same region. A. complanata is removed from synonymy with A. pirabensis (Marchesini Santos, 1958), and transferred as the type species of Placatenella n. gen. A new taxon, Camachoaster n. gen., is described to hold C. maquedensis n. sp. The Abertellidae Durham, 1955 is revised and the concept of the genus Abertella restricted to include only those forms with a posterior notch and all interambulacra discontinuous, including A. pirabensis, which is redescribed from the only known specimen, confirming that this species lacks any trace of an anal lunule but possesses features fully congruent with its placement in Abertella. Iheringiellidae n. fam. is established to house the common but taxonomically challenging taxon, Iheringiella Berg, 1898. New data on the occurrence and location of the types of Iheringiella are discussed, and comments on the status of Eoscutella mirandae Parma, 1985 provided. A tabular key to all seven South American non-lunulates is given, along with discussion of the relationship between the posterior notch and the anal lunule.

A new South American Miocene species of 'one-holed' sand dollar (Echinoidea: Clypeasteroida: Monophorasteridae).

A new species of monophorasterid sand dollar, Monophoraster telfordi n. sp., is described from the Early Miocene basal horizons of the Chenque Formation of Patagonia, Santa Cruz Province, in southern Argentina. The new taxon raises the number of known species in the family to six, and represents first unequivocal record of the genus for the Early Miocene of South America. It is therefore also the oldest member of the genus. M. telfordi is characterized by its test width to length ratio, which is much higher than for the other two described species in the genus, but less than that known for the extremely wide members of the sister taxon, Amplaster. M. telfordi is also unusual among monophorasterids in lacking broad continuity between basicoronal and post-basicoronal plates in the oral interambulacra. A key is provided to all the known species of Monophorasteridae.

Variable HIV peptide stability in human cytosol is critical to epitope presentation and immune escape.

Induction of virus-specific CD8⁺ T cell responses is critical for the success of vaccines against chronic viral infections. Despite the large number of potential MHC-I-restricted epitopes located in viral proteins, MHC-I-restricted epitope generation is inefficient, and factors defining the production and presentation of MHC-I-restricted viral epitopes are poorly understood. Here, we have demonstrated that the half-lives of HIV-derived peptides in cytosol from primary human cells were highly variable and sequence dependent, and significantly affected the efficiency of cell recognition by CD8⁺ T cells. Furthermore, multiple clinical isolates of HLA-associated HIV epitope variants displayed reduced half-lives relative to consensus sequence. This decreased cytosolic peptide stability diminished epitope presentation and CTL recognition, illustrating a mechanism of immune escape. Chaperone complexes including Hsp90 and histone deacetylase HDAC6 enhanced peptide stability by transient protection from peptidase degradation. Based on empirical results with 166 peptides, we developed a computational approach utilizing a sequence-based algorithm to estimate the cytosolic stability of antigenic peptides. Our results identify sequence motifs able to alter the amount of peptide available for loading onto MHC-I, suggesting potential new strategies to modulate epitope production from vaccine immunogens.

El coloproctólogo venezolano 2005: quiénes somos y qué hacemos? / The venezuelan colorectal surgeon 2005: who are we and what do we do?

La Sociedad Venezolana de Coloproctología desea conocer el perfil del coloproctólogo venezolano para promover y estructurar el desarrollo de la especialidad. Se envió un cuestionario a todos los miembros activos titulares y asociados de la Sociedad Venezolana de Corporación para investigar demografía, formación y experiencia coloproctológica, distribución hospitalaria y características de la práctica coloproctológica durante el último año transcurrido. Los resultados fueron analizados estadísticamente mediante análisis de varianza y test de Pearson Chi cuadrado; el nivel de significancia fue p<-0,05. La Sociedad Venezolana de Coloproctología registra 118 especialistas para abril de 2005. Se analizaron 49 cuestionarios (41,5%). La edad promedio: 48 años (33-72). La mayoría ejercen en la capital de país (55,1%). La formación ha sido principalmente en programas reconocidos (77,55%). Poco más de la mitad (53%) combinan el ejercicio privado y público y el 43% ejercen la medicina privada exclusivamente. La práctica de los miembros titulares es predominante coloproctológica (antes que de cirugía general) y principalmente de cirugía anorrectal. La cirugía laparoscópica colorrectal es practicada frecuentemente por 26,53% de la membresía general de los miembros. Los miembros títulares de la Sociedad Venezolana de Coloproctología mantienen una práctica acorde a la especialidad. Sin embargo, debe lograrse una distribución geográfica uniforme, mayor a casos de cirugía abdominal y aumentar la oferta de cirugía laparoscópica colorrectal.

Dynamical modelling of an activated sludge system of a petrochemical plant operating at high temperatures.

The Mexican petrochemical industry, Morelos S.A. de C.V., is one of the biggest and more important petroleum industries in Mexico and Latin America. It has an activated sludge system to treat its wastewater flow, which is approximately 7,000 m3/d. The wastewater contains volatile organic carbon substances classified as toxics. The old surface aeration system was changed for fine bubble diffusers; however, one major drawback of the new aeration system is that the temperature in the bioreactor has increased due to the compression of the air, which at the compressor exit reaches 85 degrees C. This effect results in the temperature in the bioreactor attaining 32 degrees C during the fall, whereas in the spring and summer, the bioreactor temperature reaches higher values than 40 degrees C. The high temperatures reduce the microorganism activity and cause a higher volatilisation rate of volatile compounds, among other effects, which affect the performance of the biological treatment. This work was performed to obtain a better modelling of the wastewater treatment from the petrochemical industry. The model describes the effect of the temperature on the performance of the biological treatment. The model was obtained from tests that were carried out in laboratory reactors with 14 L capacity, which were operated at different temperatures (from 30 to 45 degrees C), with the same wastewater and conditions as the actual system.

Removal of Cr(VI) from wastewaters in a tubular electrochemical reactor.

This work aimed at studying the electrochemical reduction of the hexavalent chromium Cr(VI) by means of a tubular reactor operating under both continuous and batch regimes. It is shown that chromium (VI) reduction to chromium (III) was exerted not only by the oxidation of iron to Fe(II) released from the steel sacrifice anodes immersed in an acid solution to aid the overall process. Also, it is shown that there was an additional contribution to chromium reduction from an ancillary reaction at the cathode, where Fe(III) ions generated after the Cr(VI) reduction are again reduced to Fe(II), this being interpreted as a catalytic effect taking place. The results are presented at pH values of 1, 1.3, 1.7, and 2: it became clear that the variable affected the solubility of the species generated in solution. The initial chromium hexavalent concentration was 1000 mg L(- 1) and it was found that after treatment times ranging from 320 to 25 minutes this could reach values as low as 0.5 mg L(- 1), depending on the operating conditions.

Colorectal malignancies in HIV-positive patients.

Due to the development of more effective medications, those infected with HIV are living longer. Consequently, more tumors and infections have been added to the AIDS-defining criteria in the last decade. Our aim was to review the occurrence and clinical course of colorectal (CR) malignancies in HIV infected/AIDS patients from a single institution. A retrospective review of HIV/AIDS patients with colorectal malignant tumors was undertaken. We included adult patients, with ELISA and Western blot test positive for HIV, and primary malignant tumors located in the colon or rectum. Malignant neoplasms of the anus were excluded for the purposes of this study. Twelve patients (9 males and 3 females), mean age 41 years, were identified with the following neoplasm: 6 adenocarcinomas (ACA), 5 non-Hodgkin lymphomas (NHL), and 1 small-cell carcinoma. Intravenous drug abuse was the main risk factor for HIV. No patient had identified risk factors for colorectal neoplasm. Five out of six patients with ACA had metastatic disease at the time of diagnosis. One patient with stage II ACA developed early liver metastases after colonic resection. Seven out of 12 patients underwent surgery. Six (85.7%) of these sustained postoperative complications, primarily wound infection. The overall survival in our series was dismal, averaging 20 months. For NHL average survival was 29 months, and 12 months for CR-ACA. This is the largest series of cases of colorectal cancer in the HIV/AIDS patient population published in the English language and the largest number of colorectal ACA reported in this unique population. Early in our experience, tumors frequently found in immunoincompetent patients were detected (NHL). More recently, we have only treated patients with colorectal ACA; none of them had no risk factors for colorectal cancer (family history, IBD, FAP, HNPCC). These patients developed tumors at earlier ages and were diagnosed at an advanced stage. Therefore, these tumors may be associated with the grade of immunosuppression induced during the course of the HIV infection and with a tumorigenic effect of the HIV on the colonic epithelium. Consequently, a high index of suspicion when evaluating chronic abdominal complaints in such patients is warranted. The use of the new antiretroviral therapy regimens should be further evaluated to know its impact in the survival.