Soluble meso and deuteroporphyrin analogs of the malaria pigment hematin anhydride.

Two soluble heme analogs of the insoluble malaria pigment hematin anhydride (HA, or ß-hematin), [Fe(III)(protoporphyrin)]2, with either mesoporphyrin (MHA) or deuteroporphyrin (DHA) are characterized by elemental analysis, SEM, IR spectroscopy, electronic spectroscopy, paramagnetic 1H NMR spectroscopy and solution magnetic susceptibility. While prior single crystal and X-ray powder diffraction results indicate all three have a common propionate linked dimer motif, there is considerable solid state variation in the conformation. This is associated with enhanced solubility of MHA and DHA. As with HA, DHA undergoes thermally promoted reversible hydration/dehydration in the solid state. Solution 1H NMR studies of DHA suggest a high spin dimeric structure with the porphyrin methyls distributed between two isomers which are also present in the solid state. These soluble iron(III)porphyrin dimers allow for the first direct solution studies by NMR and UV-Vis spectroscopies of these key species. Taken together the results illustrate the importance and utility of varying the substituents on the periphery of the porphyrin for studying heme aggregation and malaria pigment formation.

Laparoscopic and open gastrectomy for locally advanced gastric cancer: a retrospective analysis in Colombia.

INTRODUCTION: Radical gastrectomy has traditionally been the pillar treatment with curative intent for malignant tumors of the stomach. The safety of the laparoscopic approach for advanced gastric cancer (AGC) is still under debate. In our institution, laparoscopic gastrectomy is the most performed approach. OBJECTIVE: Our aim is to describe the experience of a high-volume center in the treatment of AGC in Colombia and to analyze the short-term results and the overall survival rate at 1, 3, and 5 years comparing the open and laparoscopic approaches. METHODS: A cross-sectional retrospective study of patients who underwent gastrectomy for advanced gastric cancer by open or laparoscopic approaches were performed. A Will-Coxon Mann Whitney test was performed in terms of lymph node status and surgical approach. Survival analysis was performed using the Kaplan-Meier method for overall survival at 1, 3, and 5 years. An initial log-rank test was performed to test the relationships between the operative variables and overall survival, the statistical value was accepted if p < 0.20. Data with an initial statistical relationship in the log-rank test were included in a secondary analysis using multivariate Cox proportional regression, variables with a value of p < 0.05 were considered statistically significant. RESULTS: 310 patients met the inclusion criteria. 89% underwent laparoscopic gastrectomy and 10.9% open gastrectomy. The resection margins were negative at 93.5% and the In terms of lymph node dissection, the median lymph nodes extracted was 20 (12;37), with statistically significant differences between the approaches in favor of the laparoscopic approach (Median 21 vs 12; z = - 2.19, p = 0.02). The survival rate was at 1, 3, and 5 years of 84.04%, 66.9%, and 65.47% respectively. The presence of complications and the ICU requirement have a negative impact on survival at 1 year (p 0.00). CONCLUSION: A laparoscopic approach is safe with acceptable morbidity and mortality rates for treating gastric cancer. D2 Lymphadenectomy could be performed successfully in a laparoscopic approach in a high-volume center and a properly standardized technique. Major postoperative morbidity with intensive care unit requirement seems to influence overall survival rates.

Tumores gástricos peculiares: tumor glómico, schwannoma, leiomioma y cistoadenoma en el páncreas ectópico. Serie de casos y revisión de la literatura / Unusual gastric tumors: Glomus tumor, schwannoma, leiomyoma, and cystadenoma in ectopic pancreas. A case report and literature review

Resumen Introducción: la patología gástrica es excepcionalmente benigna, se registra a nivel mundial un porcentaje de aparición de las mismas del 0,005 %-4 %. Además de lo anterior, suele plantearse como primer diagnóstico diferencial un carcinoma gástrico, por lo que la mayoría de los pacientes termina en un procedimiento quirúrgico mayor. El objetivo de este estudio fue describir una serie de casos registrados en una institución de alta complejidad, así como la revisión de la literatura al respecto del tema. Pacientes y métodos: se realizó la revisión de las bases de datos del servicio de cirugía general de la Clínica Universitaria Colombia y se encontraron 4 tumores gástricos de presentación inusual, de los cuales se hizo revisión de la historia clínica y las imágenes disponibles (diagnósticas y de las piezas de cirugía). Resultados: en la revisión de la base de datos, se encontraron 4 casos, 2 de sexo femenino y 2 de sexo masculino, con una media de edad de 51 años (26-75 años). El 100 % de los pacientes tenía una lesión en la región antral y solo uno de ellos tenía una segunda lesión a nivel prepilórico. La totalidad de los pacientes fue llevada a gastrectomía subtotal con reconstrucción en Y de Roux por abordaje laparoscópico y la media de estancia hospitalaria fue de 3,5 días (2-6 días). Conclusión: para determinar la mejor opción de tratamiento en general en pacientes con lesiones gástricas siempre hay que considerar tanto las características endoscópicas y endosonográficas como las histológicas.

Abstract Introduction: Gastric pathology is exceptionally benign with a percentage of appearance between 0.005% - 4% worldwide. Moreover, gastric carcinoma is often suggested as the first differential diagnosis and for that reason, the outcome for a vast majority of admitted patients is a major surgical procedure. This study aims to describe a series of cases recorded in a high complexity medical institution and to carry out a literature review related to that subject. Patients and Methods: Databases from the general surgery service of the Clínica Universitaria Colombia were reviewed, and four unusual gastric tumors were found. A review of the related medical records and available images (diagnostic images and surgical elements) was performed. Results: After the database review, four cases were found: two female cases and two male cases, with a mean age of 51 years (26-75 years). All the patients had lesions in the antrum area and only one of them has an additional lesion in the prepyloric region. All patients were treated with a laparoscopic subtotal gastrectomy with Roux-en-Y reconstruction and the mean length of hospital stay was 3.5 days (2-6 days). Conclusion: It is required to consider the endoscopic, endosonographic, and histological examinations and their features to determine the best treatment for patients with gastric lesions.

SARS-CoV-2 Infections Among Children in the Biospecimens from Respiratory Virus-Exposed Kids (BRAVE Kids) Study.

BACKGROUND: Children with SARS-CoV-2 infection typically have mild symptoms that do not require medical attention, leaving a gap in our understanding of the spectrum of illnesses that the virus causes in children. METHODS: We conducted a prospective cohort study of children and adolescents (<21 years of age) with a SARS-CoV-2-infected close contact. We collected nasopharyngeal or nasal swabs at enrollment and tested for SARS-CoV-2 using a real-time PCR assay. RESULTS: Of 382 children, 289 (76%) were SARS-CoV-2-infected. SARS-CoV-2-infected children were more likely to be Hispanic (p<0.0001), less likely to have a history of asthma (p=0.009), and more likely to have an infected sibling contact (p=0.0007) than uninfected children. Children ages 6-13 years were frequently asymptomatic (38%) and had respiratory symptoms less often than younger children (30% vs. 49%; p=0.008) or adolescents (30% vs. 59%; p<0.0001). Compared to children ages 6-13 years, adolescents more frequently reported influenza-like (61% vs. 39%; p=0.002), gastrointestinal (26% vs. 9%; p=0.003), and sensory symptoms (43% vs. 9%; p<0.0001), and had more prolonged illnesses [median (IQR) duration: 7 (4, 12) vs. 4 (3, 8) days; p=0.004]. Despite the age-related variability in symptoms, we found no differences in nasopharyngeal viral load by age or between symptomatic and asymptomatic children. CONCLUSIONS: Hispanic ethnicity and an infected sibling close contact are associated with increased SARS-CoV-2 infection risk among children, while a history of asthma is associated with decreased risk. Age-related differences in the clinical manifestations of SARS-CoV-2 infection must be considered when evaluating children for COVID-19 and in developing screening strategies for schools and childcare settings.

El uso de fluoruros en niños menores de 5 años. Evidencia. Revisión bibliográfica / O uso de fluoretos em crianças menores de 5 anos. Evidência. Revisão bibliográfica / The use of fluorides in children under 5 years old. Evidence. Bibliographic review

Objetivo: El propósito de esta revisión bibliográfica fue evaluar la evidencia disponible con respecto al beneficio del uso de pastas fluoradas en la prevención de la Caries de la Infancia Temprana en niños menores de 5 años. Métodos: Se realizó una revisión de literatura en varias bases de datos electrónicas como PubMed, MEDLINE, EBSCO, LILACS, CO-CHRANE; desde el año 1997 hasta el 2019. Resultados: Un total de 50 artículos cumplieron con los criterios de inclusión y en su mayoría concluyeron que el uso de fluoruros debe incorporarse en los niños debido a la cantidad de beneficios que proporciona. Conclusiones: La caries de la infancia temprana representa un inconveniente sobre todo en países en vías de desarrollo y disminuye considerablemente la calidad de vida del niño y de su familia. Utilizar pastas dentales altas en flúor puede implementarse como medida preventiva para hacer que la prevalencia de esta enfermedad disminuya en niños menores de 5 años.

Objetivo: O propósito desta revisão bibliográfica foi avaliar as evidências disponíveis sobre o benefício do uso de pastas fluoretadas na prevenção de cárie precoce em crianças menores de 5 anos de idade. Métodos: Uma revisão de literatura foi realizada em diversas bases de dados eletrônicas, como PubMed, MEDLINE, EBSCO, LILACS, COCHRANE; de 1997 a 2019. Resultados: Um total de 50 artigos preencheram os critérios de inclusão e a maioria concluiu que o uso de fluoretos deve ser incorporado em crianças devido ao montante de benefícios que ele proporciona. Conclusões: A cárie na primeira infância representa uma desvantagem especialmente nos países em desenvolvimento e reduz consideravelmente a qualidade de vida da criança e de sua família. O uso de cremes dentais fluoretados ricos em flúor pode ser implementado como uma medida preventiva para reduzir a prevalência desta doença em crianças menores de 5 anos

Objective: The aim of this literature review was to evaluate the available evidence regarding the benefit of the use of fluorinated pastes in the prevention of early childhood caries in children under 5 years of age. Methods: A literature review was conducted in several electronic databases such as PubMed, MEDLINE, EBSCO, LILACS, COCHRANE from 1997 to 2019. Results: A total of 50 articles met the inclusion criteria and most of them concluded that the use of fluorides should be utilized in children due to the amount of benefits it provides. Conclusions: Early childhood caries represents a handicap especially in developing countries as it considerably reduces the quality of life of the child and his family. Using toothpastes high in fluoride can be implemented as a preventive measure to reduce the prevalence of this disease in children under 5 years

Hydrating the Bispropionate Notch in Malaria Pigment: A New Structural Motif in the Iron(III)(deuteroporphyrin) Dimer.

Treating deuterohemin, chloro(deuteroporphyrinato)iron(III), with a non-coordinating base in DMSO/methanol allows for the isolation of [(deuteroporphyrinato)iron(III)]2 , deuterohematin anhydride (DHA), an analogue of malaria pigment, the natural product of heme detoxification by malaria. The structure of DHA obtained from this solvent system has been solved by X-ray powder diffraction analysis and displays many similarities, yet important structural differences, to malaria pigment. Most notably, a water molecule of solvation occupies a notch created by the propionate side chains and stabilizes a markedly bent propionate ligand coordinated with a long Fe-O bond, and a carboxylate cluster associated with water molecules is generated. Together, these features account for its increased solubility and more open structure, with an increased porphyrin-porphyrin separation. The IR spectroscopic signature associated with this structure also accounts for the strong IR band at 1587 cm-1 seen for many amorphous preparations of synthetic malaria pigment, and it is proposed that stabilizing these structures may be a new objective for antimalarial drugs. The important role of the vinyl substituents in this biochemistry is further demonstrated by the structure of deuterohemin obtained by single-crystal X-ray diffraction analysis.

Utilidad de la laparoscopia de estadificación frente a la tomografía axial computarizada para detectar metástasis peritoneales en el adenocarcinoma gástrico avanzado / Usefulness of staging laparoscopy vs CT scan to detect metastatic peritoneal disease in advanced gastric adenocarcinoma

Introducción. El adenocarcinoma gástrico es una de las neoplasias más frecuentes. La tomografía computarizada abdominal con contraste es el método estándar para la estadificación; tiene una sensibilidad del 30 al 73 % y una especificidad del 83 al 100 %. La laparoscopia detecta hasta el 30 % de los casos de enfermedad metastásica que no se haya observado en los estudios de imágenes. En la Clínica Universitaria Colombia se realiza estadificación rutinaria con tomografía y laparoscopia más lavado peritoneal.Objetivos. Determinar la utilidad de la laparoscopia para detectar la carcinomatosis peritoneal en los pacientes con adenocarcinoma gástrico avanzado en un centro de referencia. Materiales y métodos. Se llevó a cabo un estudio descriptivo y retrospectivo, en el cual se analizaron todas las historias clínicas de los pacientes con cáncer gástrico atendidos en la Clínica Universitaria Colombia entre el 2013 y el 2016. Se confrontó el hallazgo de la laparoscopia con el de la tomografía abdominal, buscando falsos negativos para la enfermedad peritoneal.Resultados. Se incluyeron 94 pacientes con adenocarcinoma gástrico. La localización en el cuerpo gástrico fue la más frecuente (47,9 %). La tomografía reportó estadio T3 en el 56,4 %, N0 en el 55,3 % y M0 en el 97,9 % de los casos. La laparoscopia reportó estadio T3 en el 43,6 %, ganglios comprometidos en el 56,4 % y carcinomatosis peritoneal (M1) en el 11,7 %.Discusión. Un radiólogo experimentado detecta una gran proporción de las enfermedades peritoneales, pero la laparoscopia detecta hasta 11 % de aquellas que no son evidentes en los exámenes de imágenes. El lavado pe-ritoneal no prolonga el tiempo quirúrgico ni incrementa la morbilidad, lo cual favorece su realización rutinaria.Se puede recomendar la laparoscopia en aquellos pacientes con resultados tomográficos negativos, evitando la cirugía cuando la neoplasia es irresecable. La laparoscopia tiene un impacto positivo en el manejo integral del cáncer gástrico, acorde con la literatura mundial

Introduction: Gastric adenocarcinoma is one of the most frequent neoplasms. Abdominal computed tomography is the standard for staging; It has sensitivity of 30 to 73% and specificity of 83 to 100%. Laparoscopy detects up to 30% of negative metastatic disease in images. At Clínica Universitaria Colombia performs routine staging with tomography and laparoscopy plus peritoneal lavage.Objectives: To determine the usefulness of laparoscopy for the detection of peritoneal carcinomatosis in patients with advanced gastric adenocarcinoma in a reference centerMaterials and methods: A retrospective descriptive study was carried out, where all the clinical histories of patients with gastric cancer between 2013 and 2016 were analyzed.Results: A total of 94 patients with gastric adenocarcinoma were included in the study; Corporal localization was more frequent (47.9%). The tomography reported stage T3 in 56.4%, N0 in 55.3% and M0 97.9%. Laparoscopy reported T3 stage in 43.6%, lymph nodes were involved in 56.4% and the presence of peritoneal carcinomatosis (M1) was 11.7%.Discussion: An experienced radiologist shows high detection of peritoneal disease, but laparoscopy detects up to 11% of the disease not evident on images. The peritoneal lavage does not prolong the surgical time nor increa-ses morbidity, which favors its routine performance. We can recommend laparoscopy in patients with negative tomography, avoiding surgery in unresectable disease. Laparoscopy has a positive impact on the management of gastric cancer, according to world literature

Supervivencia y complicaciones en pacientes con cáncer gástrico y de la unión gastroesofágica tratados con quimioterapia perioperatoria más cirugía comparada con cirugía más terapia adyuvante: estudio multicéntrico, Bogotá D.C. 2010-2017 / Survival and complications of patients with gastric cancer and with cancer of the gastroesophageal junction treated with perioperative chemotherapy and surgery compared with patients managed with adjuvant chemotherapy and surgery; multicentric study, 2010-2017. Bogotá, Colombia

Introducción. El tratamiento oncológico adicional a la cirugía en los pacientes con cáncer gástrico, sigue siendo un tema de debate. Se compararon el pronóstico y las complicaciones de la quimioterapia perioperatoria con los de la quimioterapia adyuvante, para identificar el mejor esquema de tratamiento. Materiales y métodos. Se llevó a cabo un estudio longitudinal, retrospectivo y de cohorte histórica, que incluía todos pacientes que recibieron alguno de los dos esquemas de tratamiento. Los principales objetivos fueron evaluar la supervivencia y las complicaciones perioperatorias (fístula, sangrado, muerte y toxicidad) en cada grupo. Resultados. Se incluyeron 168 pacientes que cumplieron los criterios de inclusión. Comparado con el grupo de quimioterapia adyuvante, el grupo de quimioterapia perioperatoria tuvo una mayor supervivencia a 2 y 5 años (80,1 Vs. 61,2 %; 69,8 Vs. 43,6 %) (p=0,003). No hubo diferencia estadísticamente significativa en la tasa de complicaciones perioperatorias entre los dos grupos (4,11 Vs. 10,64 %) (p=0,151). Hubo un aumento en la necesidad de transfusiones en el grupo con quimioterapia perioperatoria. Discusión. La quimioterapia perioperatoria aumenta la supervivencia a largo plazo de los pacientes con cáncer gástrico localmente avanzado, sin un aumento significativo en la tasa de complicaciones perioperatorias. Hay un aumento en la necesidad de transfusiones en el grupo de quimioterapia perioperatoria, sin que esto empeore el pronóstico de los pacientes

Introduction: Oncological management in addition to surgery in patients with gastric cancer remains a matter of debate. We conducted a retrospective longitudinal study to compare the prognosis and complications between perioperative chemotherapy and adjuvant chemotherapy to identify the best treatment scheme. Materials and methods: A longitudinal, retrospective historical cohort study was carried out that included all patients who received one of the two treatment schemes. The main objectives were to evaluate overall survival and perioperative complications (fistula, bleeding, death and toxicity) in each group. Results: 168 patients met the inclusion criteria. Compared with the adjuvant chemotherapy group, the perioperative chemotherapy group had greater survival at 2 and 5 years (80.1% vs. 61.2%, 69.8% vs. 43.6% p=0.003). There was no statistically significant difference in the rate of perioperative complications between the two groups (4.11% vs. 10.64%, p = 0.151). There was an increase in the transfusion requirement in the perioperative chemotherapy group. Discussion: Perioperative chemotherapy increases the long-term survival of patients with locally advanced gastric cancer, without a significant increase in the rate of perioperative complications. There is an increase in the transfusion requirement of the perioperative chemotherapy group without this worsening the prognosis of the patients

Father's Perceptions of their Role and Involvement in the Family: A Qualitative Study in a Colombian Sample / Percepciones del padre sobre su rol e involucramiento en la familia: un estudio cualitativo en una muestra colombiana

Abstract The purpose of this study was to explore fathers' perceptions about their role in the family, and the characteristics of their involvement in their children's lives in the Colombian context. The sample consisted of 12 Colombian fathers. The study used a qualitative methodology, one-hour in depth interviews were conducted with the participants. Results indicated important changes in the role of fathers and mothers in Colombian families. Fathers' perceptions departed to some extent from the traditional pattern attributed to nuclear families, where men are considered as the only economic provider and authority figure in the family. This departure places fathers in a category we would call "in transition", which includes perceptions of more equitable parental roles within the family and a combination of features from other typologies of fatherhood proposed in the literature. Fathers also reported a desire to participate more at home and to be more involved in their children's lives; they also emphasized the importance of expressing love and affection to their children. Work-family conflict and the impact of the quality of the father-child relationship emerged as important categories in the fathers' perceptions of their role and involvement in the family. In Colombia research on fathers is scarce and family policies mainly focus on mothers as the principal caregiver. A better understanding of fathers' roles and involvement in the family and with children will contribute to the development of programs and policies oriented toward all family members and family relationship systems.

Resumen El propósito de este estudio fue explorar las percepciones de los padres sobre su rol en la familia y las características de su involucramiento en la vida de los hijos en el contexto colombiano. La muestra estuvo conformada por 12 padres colombianos. El estudio siguió una metodología cualitativa en la cual se llevaron a cabo entrevistas en profundidad de una hora de duración con los participantes. Los resultados indicaron cambios importantes en el rol de los padres y las madres en las familias colombianas. Las percepciones de los padres se alejaron en alguna medida del patrón tradicional atribuido a las familias nucleares en las cuales los hombres son considerados como los proveedores exclusivos y las figuras de autoridad de la familia. Esta separación ubica a los padres en una categoría que nosotros llamaríamos "en transición", la cual incluye percepciones de roles parentales más equitativos dentro de la familia y una combinación de rasgos de otras tipologías de la paternidad propuestos en la literatura. Los padres también reportaron un deseo por participar más en sus hogares y por estar más involucrados en la vida de sus hijos. Adicionalmente, ellos enfatizaron en la importancia de expresar amor y afecto a sus hijos. El conflicto entre el trabajo y la familia y el impacto de la calidad de la relación padre-hijo emergieron como categorías fundamentales en las percepciones de los padres sobre su rol e involucramiento en la familia. En Colombia, la investigación sobre los papás es escasa y las políticas de familia se centran principalmente en las madres como cuidadoras principales. Una mayor comprensión del rol de los papás y de su involucramiento en la familia y con los hijos contribuirá al desarrollo de programas y las políticas orientadas hacia todos los miembros de la familia y hacia los diferentes sistemas de relación en el contexto familiar.

Proceso de diseño de un currículo por competencia profesional para los postgrados de medicina interna de la Universidad Central de Venezuela / Process design of a curriculum for professional competence for postgraduates of internal medicine at the Universidad Central de Venezuela

En el año 2003 se inicia desde el Comité Nacional de Educación Médica de la Sociedad Venezolana de Medicina Interna y el Centro de Investigación y Desarrollo de la Educación Médica de la UCV un proceso para elaboración en el marco del paradigma Socio-Cognitivo y de la Educación Basada en la Competencia Profesional, de una metodología amigable y transferible para el diseño de currículos por competencia profesional, que dió como resultado un nuevo currículo para los postgrados de Medicina Interna de la UCV. Se trata de la primera aplicación del Modelo Socio-Cognitivo en el campo de la educación médica para el diseño de currículo por competencia profesional, lo cual requiere de la comprensión por parte del profesorado de nuevos modelos educativos para el mejoramiento de la educación médica de postgrado, como alternativas al currículum tradicional. El currículo por competencia profesional para los postgrados de medicina interna de la UCV, por su concepción y fundamentos es un recurso para facilitar la transparencia en las estructuras educativas de los postgrados de esta especialidad médica en el país e impulsar la innovación educativa a través de la comunicación de experiencias y la identificación de buenas prácticas. Así como, para estimular la innovación y la calidad en educación médica mediante la reflexión y el intercambio, al desarrollar y compartir información relativa al diseño de currículos por competencia profesional y crear una estructura curricular modelo como punto de referencia. La aprobación e implementación del primer currículo por competencia profesional de los postgrados de medicina interna en la UCV, implicó la capacitación del profesorado en su diseño, los cuales serán a su vez promotores y facilitadores del cambio curricular en la propia institución. Y además, requerirá del compromiso de las autoridades universitaria y demás entes rectores de la educación universitaria, para la adecuación de la normativa que permite la innovación educativa...

In 2003, the National Committee on Medical Education of the Venezuelan Society of Internal Medicine and the Center for Research and Development of Medical Education of the Universidad Central de Venezuela (UCV) started the process of elaborating, under the Socio-Cognitive paradigm and professional competency based Education, a friendly and transferable methodology to design curricula based on professional competence. This resulted in a new curriculum for Internal Medicine postgraduates in the UCV. This is the first application of the Socio-Cognitive Model in the field of medical education on professional competency based curriculum design. It is required that teachers of the new educational model understand it fully so there is an improvement of the medical education graduate, as alternatives to the traditional curriculum. The curriculum for professional competence postgraduate in internal medicine at the UCV, in concept and fundamentals is a resource to facilitate transparency in the educational structures of the graduate in this medical specialty in the country. It also encourages educational innovation through experience sharing and good practices identification. It intends as well to stimulate innovation and quality in medical education through reflection and exchange; developing and sharing information on the design of professional competency based curricula, creating a benchmark curriculum model. The adoption and implementation of the first curriculum for professional competence postgraduate in internal medicine at the UCV, involves curricula design capacitation for teachers. They shall become promoters and facilitators of curriculum change in the institution. Besides that, the commitment of the university authorities and other higher education governing bodies will be required to adapt the rules in order to allow educational innovation and self-renewal

Personal exposure to particulate matter in commuters using different transport modes (bus, bicycle, car and subway) in an assigned route in downtown Santiago, Chile.

The objective of this study was to compare personal exposure to particulate matter (fine and ultrafine particles) in commuters using different transport modes (bicycle, bus, car and subway) in a busy, assigned route in downtown Santiago, Chile. Volunteers carrying personal samplers completed scheduled commutes during the morning rush hours, while central site measurements were conducted in parallel. A total of 137 valid commutes were assessed. The impact of central site, traffic and other variables was explored with regression models. PM2.5 personal concentrations were equal to or slightly above central site measurements, while UFP personal concentrations were above them. Regression models showed impacts of both background levels and traffic emissions on personal PM2.5 and UFP exposure. Traffic impacts varied with transport modes. Estimates of traffic impacts on personal PM2.5 exposure were 2.0, 13.0, 16.9 and 17.5 µg m(-3), for car, bicycle, subway and bus, respectively; while for UFP exposure were 8400, 16 200, 25 600 and 30 100 counts per cm(3), for subway, car, bicycle and bus, respectively. After controlling the central site and transport mode, higher temperatures increased PM2.5 exposure and decreased UFP ones, while the wind direction affected UFP personal exposure. In conclusion, we found significant impacts of both central site background measurements and traffic emissions on personal exposure of volunteer commuters in an assigned route in Santiago, with impacts varying with transport modes.

Toward understanding the chloroquine action at the molecular level in antimalarial therapy--X-ray absorption studies in acetic acid solution.

The local atomic structure around the central iron of the synthetic soluble analog of malarial pigment in acetic acid solution and with addition of chloroquine as found by X-ray absorption spectroscopy is reported. The special interest was drawn to the axial linkage between the central iron atom of the ferriprotoporphyrin IX (FePPIX) coordinated axially to the propionate group of the adjacent FePPIX. This kind of bonding is typical for hematin anhydride. Detailed analysis revealed differences in oxygen coordination sphere (part of dimer linkage bond) between synthetic equivalent of hemozoin in the powder state and dissolved in acetic acid and water at different concentrations mimicking the physiological condition of the parasite's food vacuole. The results of performed studies suggest that the molecular structure of synthetic analogue of hemozoin is no longer dimer-like in acidic solution. Further changes in atomic order around Fe are seen after addition of the antimalarial drug chloroquine.

Understanding chloroquine action at the molecular level in antimalarial therapy: X-ray absorption studies in dimethyl sulfoxide solution.

X-ray absorption spectroscopy is used to determine the local atomic structure around the iron atom from a soluble synthetic analogue of malaria pigment (hemozoin), cf. ferrimesoporphyrin IX of mesohematin anhydride, in the absence or presence of chloroquine (CQ) in dimethyl sulfoxide (DMSO). Of particular note are the CQ-induced changes in the structure of mesohematin anhydride, which might confirm the formation of CQ-ferrimesoporphyrin IX complex. Examination of solutions of mesohematin anhydride dissolved in DMSO reveals preservation of the dimerlike structure with the central iron atoms of the ferric porphyrin IX reciprocally linked by propionate side chains, which is typical for hematin anhydride (ß-hematin). In the presence of CQ, additional light atoms, such as nitrogen, carbon, and oxygen, were detected surrounding the iron in a distance ranging from 2.48 to 3.77 Å. The changes introduced by CQ in DMSO are different from that observed in the acetic acid solution.

[Prognostic and survival factors among pediatric patients with ependymomas]. / Factores pronósticos y sobrevida de pacientes pediátricos con ependimomas.

BACKGROUND: Ependymomas constitute the third most common intracranial tumors in children. Risk factors include age, location, extent of surgical excision, and radiation therapy. Recently, chromosomal imbalances have been described. OBJECTIVE: Determine global survival of patients with ependymomas according to different prognostic factors. METHODS: We reviewed the medical charts of every pediatric patient with ependymoma from 1996 to 2005. Genomic imbalances were determined using comparative genomic hybridization (CGH). Survival was calculated using the Kaplan and Meier method. We used the Log Rank test for each risk factor. Death risk was calculated by odds ratio (OR). RESULTS: We included 24 patients. Global survival was 58.04%. The presence of chromosomal imbalances, particularly in chromosome 21, significantly affected survival Being under 5 years of age, anaplastic histology, chemotherapy other than ICE (ifosfamida-carboplatin-etoposide) and partial resection increased the risk of death. CONCLUSIONS: Known risk factors were confirmed in our study, including chromosomal imbalances. We describe a new chromosomal imbalance in chromosome 21 among 30% of study participants.

Factores pronósticos y sobrevida de pacientes pediátricos con ependimomas / Prognostic and survival factors among pediatric patients with ependymomas

Antecedentes: El ependimoma es el tercer tumor intracraneano más frecuente en pediatría. Los factores que influyen en el pronóstico son la localización, la edad del paciente, la resección quirúrgica y el tratamiento con radioterapia. Recientemente se ha descrito la presencia de alteraciones cromosómicas en el tumor como factor de mal pronóstico. El objetivo de esta investigación fue determinar la sobrevida de pacientes pediátricos con ependimoma de acuerdo con los diferentes factores pronósticos. Métodos: Se revisaron los expedientes de pacientes pediátricos con ependimoma de 1996 a 2005. Se determinaron las alteraciones cromosómicas mediante hibridación genómica comparativa. Se calculó la sobrevida de acuerdo con el método Kaplan-Meier y prueba de log rank de acuerdo a cada factor pronóstico. Se calculó el riesgo de morir para cada factor de acuerdo con la razón de momios. Resultados: Se incluyeron 24 pacientes. La sobrevida global fue de 58.04%. La presencia de alteraciones cromosómicas, particularmente en el cromosoma 21, afectó significativamente la sobrevida. La edad menor a cinco años, la histología anaplásica, la quimioterapia diferente a ifosfamida-carboplatino-etopósido y la resección parcial aumentaron el riesgo de morir. Conclusiones: Se confirman los factores descritos anteriormente en la literatura, incluyendo alteraciones cromosómicas. Se describe un nuevo desbalance en el cromosoma 21 en 30% de los pacientes.

BACKGROUND: Ependymomas constitute the third most common intracranial tumors in children. Risk factors include age, location, extent of surgical excision, and radiation therapy. Recently, chromosomal imbalances have been described. OBJECTIVE: Determine global survival of patients with ependymomas according to different prognostic factors. METHODS: We reviewed the medical charts of every pediatric patient with ependymoma from 1996 to 2005. Genomic imbalances were determined using comparative genomic hybridization (CGH). Survival was calculated using the Kaplan and Meier method. We used the Log Rank test for each risk factor. Death risk was calculated by odds ratio (OR). RESULTS: We included 24 patients. Global survival was 58.04%. The presence of chromosomal imbalances, particularly in chromosome 21, significantly affected survival Being under 5 years of age, anaplastic histology, chemotherapy other than ICE (ifosfamida-carboplatin-etoposide) and partial resection increased the risk of death. CONCLUSIONS: Known risk factors were confirmed in our study, including chromosomal imbalances. We describe a new chromosomal imbalance in chromosome 21 among 30% of study participants.

Synthesis, characterization, and in vitro antimalarial and antitumor activity of new ruthenium(II) complexes of chloroquine.

The new Ru(II) chloroquine complexes [Ru(eta(6)-arene)(CQ)Cl2] (CQ = chloroquine; arene = p-cymene 1, benzene 2), [Ru(eta(6)-p-cymene)(CQ)(H2O)2][BF4]2 (3), [Ru(eta(6)-p-cymene)(CQ)(en)][PF6]2 (en = ethylenediamine) (4), and [Ru(eta(6)-p-cymene)(eta(6)-CQDP)][BF4]2 (5, CQDP = chloroquine diphosphate) have been synthesized and characterized by use of a combination of NMR and FTIR spectroscopy with DFT calculations. Each complex is formed as a single coordination isomer: In 1-4, chloroquine binds to ruthenium in the eta(1)-N mode through the quinoline nitrogen atom, whereas in 5 an unprecedented eta(6) bonding through the carbocyclic ring is observed. 1, 2, 3, and 5 are active against CQ-resistant (Dd2, K1, and W2) and CQ-sensitive (FcB1, PFB, F32, and 3D7) malaria parasites (Plasmodium falciparum); importantly, the potency of these complexes against resistant parasites is consistently higher than that of the standard drug chloroquine diphosphate. 1 and 5 also inhibit the growth of colon cancer cells, independently of the p53 status and of liposarcoma tumor cell lines with the latter showing increased sensitivity, especially to 1 (IC50 8 microM); this is significant because this type of tumor does not respond to currently employed chemotherapies.

Sobrevida de pacientes con cáncer de pulmón a células no pequeñas estadio IV: posible beneficio de la quimioterapia en la práctica asistencial / Survival of patients with non-small cells lung cancer, stage IV: possible benefit of chemotherapy

El objetivo del presente estudio fue evaluar la sobrevida de pacientes portadores dee cáncer de pulmón a células no pequeñas (CPCNP) estadio IV manejados según la práctica clínica estándar, de acuerdo al tratatamiento instituído. Se evaluaron retrospectivamente todos los pacientes portadores ded CPCNP estadio IV y sin tratamientos previos asistidos en el período enero 1994 - julio 1997. Se estudiaron 86 pacientes, 71 del sexo masculino y 15 del sexo femenino. La edad mediana fue 61 años(rango: 35-85). 34 pacientes recibieron quimioterapia (QT) en base a una sal dede platino, asociada o no a radioterapia (RT) (grupo 1); 26 fueron tratados con RT torácica (grupo 2), y 26 recibieron tratamiento sintomático exclusivo (grupo 3). Se realiazó el análisis de sobrevida de acuerdo al tratamiento realizado y teniendo en cuenta otras variables con posible influencia en la sobrevida. La mediana de los tiempos de sobrevida de todos los pacientes estudiados fue de 4,5 meses (IC 95 por ciento: 3,0-6,5 meses). El riesgo de morir fue significativamente superior para los pacientes del grupo 1 en relación a los pacientes de los grupos 2 y 3 (modelo de Cox, p=0,0002). La mediana de los tiempos dee sobrevida de los grupos 1,2 y 3 fue 7 meses versus 3,2 meses versus 2 meses, respectivamente. Se concluye que la sobrevida de los pacientes con CPCNP estadio IV manejados según la práctica clínica estándar es similar a la reportada en los estudios clínicos prospectivos, siendo superior en el grupo tratado con QT basada en cisplatino.