Dabrafenib plus trametinib treatment in patients with anaplastic thyroid carcinoma: an Argentinian experience.

PURPOSE: To present our real-life experience with dabrafenib and trametinib (D-T) treatment in patients with BRAF V600E-mutated ATC in Argentina. PATIENTS Y METHODS: We included five patients from four different hospitals. The median age was 70 years, and 60% were male. The performance status at diagnosis was grade 0 in 60% and grade 2 in 40% of patients. Four patients could undergo total thyroidectomy; in one of them, surgical treatment was amenable due to the indication of D-T as neoadjuvant therapy. From the total cohort, the best response to treatment was complete response in 40%, partial response in 20%, and stable disease in 20%. The median duration of response was 20 weeks, ranging from 16 to 92 weeks. All patients experienced at least one adverse event (AE). Grade ≥3 AEs were observed in two (40%) patients. They were upper gastrointestinal bleeding and subclavian vein thrombosis. The median follow-up was 20 weeks (range: 16 to 92). CONCLUSION: This report contributes to illustrate the feasibility and effectiveness of D-T treatment in five patients with loco-regionally advanced and metastatic BRAF V600E-mutated ATC in a real-life setting. A multidisciplinary approach and rapid molecular-tailored testing are essential to begin this therapeutic option.

Black carbon footprint of human presence in Antarctica.

Black carbon (BC) from fossil fuel and biomass combustion darkens the snow and makes it melt sooner. The BC footprint of research activities and tourism in Antarctica has likely increased as human presence in the continent has surged in recent decades. Here, we report on measurements of the BC concentration in snow samples from 28 sites across a transect of about 2,000 km from the northern tip of Antarctica (62°S) to the southern Ellsworth Mountains (79°S). Our surveys show that BC content in snow surrounding research facilities and popular shore tourist-landing sites is considerably above background levels measured elsewhere in the continent. The resulting radiative forcing is accelerating snow melting and shrinking the snowpack on BC-impacted areas on the Antarctic Peninsula and associated archipelagos by up to 23 mm water equivalent (w.e.) every summer.

Evaluation of MODIS-derived estimates of the albedo over the Atacama Desert using ground-based spectral measurements.

Surface albedo is an important forcing parameter that drives the radiative energy budget as it determines the fraction of the downwelling solar irradiance that the surface reflects. Here we report on ground-based measurements of the spectral albedo (350-2200 nm) carried out at 20 sites across a North-South transect of approximately 1300 km in the Atacama Desert, from latitude 18° S to latitude 30° S. These spectral measurements were used to evaluate remote sensing estimates of the albedo derived from the Moderate Resolution Imaging Spectroradiometer (MODIS). We found that the relative mean bias error (RMBE) of MODIS-derived estimates was within ± 5% of ground-based measurements in most of the Atacama Desert (18-27° S). Although the correlation between MODIS-derived estimates and ground-based measurements remained relatively high (R= 0.94), RMBE values were slightly larger in the southernmost part of the desert (27-30° S). Both MODIS-derived data and ground-based measurements show that the albedo at some bright spots in the Atacama Desert may be high enough (up to 0.25 in visible range) for considerably boosting the performance of bifacial photovoltaic technologies (6-12%).

Angioplastia de tronco de la coronaria izquierda no protegido: evolución clínica al año y a los 3 años. Predictores de eventos / Unprotected Left Main Percutaneous Coronary Intervention: One and 3-Year Evolution. Event Prediction

RESUMEN Introducción: La angioplastia de Tronco de la Coronaria Izquierda es una opción terapéutica en pacientes con anatomía favorable. Objetivos: Reportar nuestra experiencia en el tratamiento de estos pacientes, así como su evolución clínica y evaluar los predictores de eventos clínicos durante el seguimiento. Material y Métodos: Análisis retrospectivo de pacientes intervenidos entre 2011 y 2017 por obstrucción significativa del Tronco de la Coronaria Izquierda (Clínica Bazterrica y Clínica Santa Isabel). Se registró la incidencia de eventos clínicos al año y alejados (3 años como mínimo). Se realizó un análisis univariado y multivariado (modelo de riesgos proporcionales de Cox) para identificar aquellas variables asociadas a la ocurrencia de eventos (muerte e infarto). Resultados: Se incluyeron consecutivamente 95 pacientes, de los cuales en 39 el procedimiento fue no electivo (41,1%). La mortalidad global fue 9,3 % a los 12 meses y 13,6% alejada. La tasa de infarto de miocardio no fatal fue 7,2% al año y 14,5% alejada. La tasa de accidente cerebrovascular fue 2,1% y la de revascularización fue 10,4% a los 12 meses. El único predictor multivariado de eventos a 12 meses fue la indicación no electiva del procedimiento (p = 0,003). Cuando consideramos los eventos ocurridos luego del primer año, el único predictor multivariado fue la edad >70 años (p <0,0001). Conclusiones: Nuestros resultados de la angioplastia del Tronco de la Coronaria Izquierda corresponden a los reportados por otros autores. La ocurrencia de eventos al año y eventos alejados se relacionó con condiciones identificables como la indicación del procedimiento y la edad de los pacientes.

ABSTRACT Background: Left main percutaneous coronary intervention is a therapeutic option for patients with favorable anatomy. Objectives: The aim of this study was to report our experience in the treatment of these patients, their clinical evolution and the variables associated with clinical events during follow-up. Methods: This was a retrospective analysis of patients that underwent percutaneous coronary artery intervention for left main obstructive disease between 2011 and 2017 at Clínica Bazterrica and Clínica Santa Isabel. The incidence of clinical events was evaluated at one year and at long-term follow-up (at least 3 years after the intervention). An univariate and multivariate analysis (Cox proportional risk model) was performed to identify event-associated variables (death and infarction). Results: Among a total of 95 patients included in the study, 39 (41.1%) underwent a non-elective procedure. The rate of overall mortality was 9.3% at 12 months and 13.6% at long-term follow-up, and that of non-fatal myocardial infarction 7.2% and 14.5%, respectively. On the other hand, the rate of stroke and revascularization was 2.1% and 10.4% at 12 months, respectively. On multivariate analysis, the only independent predictors of adverse clinical events were non-elective intervention at 12 months (p = 0.003) and age >70 years after the first year (p <0.0001). Conclusions: Our results of left main percutaneous coronary intervention correspond with those reported by other authors. The incidence of one-year and long-term clinical events was associated with identifiable conditions, as procedure indication and age of the patients at the time of intervention

Evaluation of Antarctic Ozone Profiles derived from OMPS-LP by using Balloon-borne Ozonesondes.

Predicting radiative forcing due to Antarctic stratospheric ozone recovery requires detecting changes in the ozone vertical distribution. In this endeavor, the Limb Profiler of the Ozone Mapping and Profiler Suite (OMPS-LP), aboard the Suomi NPP satellite, has played a key role providing ozone profiles over Antarctica since 2011. Here, we compare ozone profiles derived from OMPS-LP data (version 2.5 algorithm) with balloon-borne ozonesondes launched from 8 Antarctic stations over the period 2012-2020. Comparisons focus on the layer from 12.5 to 27.5 km and include ozone profiles retrieved during the Sudden Stratospheric Warming (SSW) event registered in Spring 2019. We found that, over the period December-January-February-March, the root mean square error (RMSE) tends to be larger (about 20%) in the lower stratosphere (12.5-17.5 km) and smaller (about 10%) within higher layers (17.5-27.5 km). During the ozone hole season (September-October-November), RMSE values rise up to 40% within the layer from 12.5 to 22 km. Nevertheless, relative to balloon-borne measurements, the mean bias error of OMPS-derived Antarctic ozone profiles is generally lower than 0.3 ppmv, regardless of the season.

Real-life use of lenvatinib in patients with differentiated thyroid cancer: experience from Argentina.

PURPOSE: To describe the experience with radioiodine-resistant differentiated thyroid cancer (RR-DTC) patients treated with lenvatinib in two university hospitals from Argentina. METHODS: Adult patients with a diagnosis of RR-DTC treated with lenvatinib from April 2017 to February 2020 were registered into a retrospective database. Primary objectives were assessment of progression-free survival (PFS) and tumor response evaluated according to RECIST v 1.1. Adverse events (AEs) were evaluated by using Common Terminology Criteria for Adverse Events v5.0. RESULTS: Twenty-two patients were treated with lenvatinib, 13 of whom had previously received one or more multikinase inhibitors. Median duration of treatment was 7.1 months (2.2-24). Best overall response was complete response in one patient (4.5%), partial response in seven (31.8%), stable disease in seven (31.8%), and progressive disease in six (27.3%). Median PFS was 13.7 months (95% CI 3.2-24.2). All patients experienced at least one AE. Grade ≥3 AEs were observed in eight (36.4%) patients. Hypertension was the most frequent AE (63.6%) and the most common grade ≥3 AE (22.7%). Definitive withdrawal was necessary in two patients due to recurrent proteinuria (9%). CONCLUSIONS: Tumor responses and PFS in our study were in line with other real-life clinical data and they seem to be inferior to the reported in the SELECT trial, probably related to the higher number of patients with prior MKI therapy, comorbidities, and poor performance status. Although virtually all patients experienced AEs, most of them were manageable and rarely a definitive withdrawal was necessary.

Elemental and Mineralogical Composition of the Western Andean Snow (18°S-41°S).

The snowpack is an important source of water for many Andean communities. Because of its importance, elemental and mineralogical composition analysis of the Andean snow is a worthwhile effort. In this study, we conducted a chemical composition analysis (major and trace elements, mineralogy, and chemical enrichment) of surface snow sampled at 21 sites across a transect of about 2,500 km in the Chilean Andes (18-41°S). Our results enabled us to identify five depositional environments: (i) sites 1-3 (in the Atacama Desert, 18-26°S) with relatively high concentrations of metals, high abundance of quartz and low presence of arsenates, (ii) sites 4-8 (in northern Chile, 29-32°S) with relatively high abundance of quartz and low presence of metals and arsenates, (iii) sites 9-12 (in central Chile, 33-35°S) with anthropogenic enrichment of metals, relatively high values of quartz and low abundance of arsenates, (iv) sites 13-14 (also in central Chile, 35-37°S) with relatively high values of quartz and low presence of metals and arsenates, and v) sites 15-21 (in southern Chile, 37-41°S) with relatively high abundance of arsenates and low presence of metals and quartz. We found significant anthropogenic enrichment at sites close to Santiago (a major city of 6 million inhabitants) and in the Atacama Desert (that hosts several major copper mines).

Thermotherapy in calcaneal infection due to Prototheca wickerhamii / Termoterapia en infección calcánea debida a Prototheca wickerhamii

No disponible

¿Tiene valor pedir más de un perfil inmunohistoquímico en tumores multicéntricos o multifocales de mama? / Has it any value to request more than one immunohistochemical profile in multicentric or multifocal breast tumors?

Introducción La estimación de la prevalencia de tumores mamarios multicéntricos y multifocales es muy variable según los distintos estudios analizados. Esto se debe, en gran parte, a la falta de consistencia al momento de definir ambas formas de presentación. Por este motivo, muchos autores hacen referencia a este tipo de tumor como carcinoma mamario múltiple. El tnm, uicc-ajcc (7ma edición) define a esta forma de presentación como múltiples lesiones de carcinoma mamario presentes en la misma mama de manera sincrónica. Según el Colegio Americano de Patólogos (cap), la caracterización biológica de la lesión de mayor tamaño tumoral es suficiente, salvo que se presenten discordancias entre los tipos histológicos o grados tumorales. A pesar de que la estrategia de evaluar una única lesión en este aspecto tiene claras ventajas en costos y viabilidad, el cáncer de mama es considerado en sí mismo una enfermedad heterogénea, y, al seguir las recomendaciones anteriormente expresadas, se estaría asumiendo que estos tipos de tumores múltiples tienen un comportamiento biológico homogéneo. Por tal motivo, en el presente estudio se analiza el comportamiento biológico (re, rp, her2 y Ki-67) en cada foco tumoral presente, para poder establecer si, al seguir las recomendaciones vigentes actualmente, no estaríamos subtratando a un grupo de nuestras pacientes. Objetivos Evaluar la concordancia en los perfiles inmunohistoquímicos de cada tumor presente de manera sincrónica en la mama. Establecer la asociación entre los tamaños, los tipos histológicos y el grado tumoral. Material y método Se realizó un estudio observacional, retrospectivo en pacientes con diagnóstico y confirmación por estudio histopatológico de pieza quirúrgica de carcinoma mamario multifocal o multicéntrico. De un total de 722 pacientes, se obtuvieron datos de 45 historias clínicas, en un período comprendido, entre marzo de 2015 y septiembre de 2016 (18 meses). Las pacientes analizadas fueron diagnosticadas y tratadas en la Unidad de Mastología de la Clínica Breast y el Hospital Italiano de la Ciudad de La Plata, Buenos Aires, Argentina. Los resultados histopatológicos e Inmunohistoquímicos (ihq) se obtuvieron de los patólogos pertenecientes a nuestro centro mastológico. El perfil ihq se realizó en tejido tumoral obtenido mediante biopsia con aguja gruesa o pieza quirúrgica. Se determinó: Receptores Hormonales para Estrógeno (re) y Progesterona (rp), her2 y Ki-67. Resultados • Se observó una incidencia de 6,23% de tumores multicéntricos, multifocales. • En cuanto al tipo histológico, la correlación entre biopsia con aguja gruesa y análisis de pieza quirúrgica fue del 100% (n:45 pacientes). • Grado histológico tumoral en los distintos focos: 84% (n=38) de concordancia y 16% (n=7) de discordancia. • Variabilidad de subtipos tumorales en cada foco: el 67% (n=30) no presentó discordancias. • Perfil inmunohistoquímico (ihq): el porcentaje de pacientes con concordancia en el perfil inmunohistoquímico y el subtipo tumoral fue superior al grupo de pacientes que presentaron discordancias. En el grupo de pacientes con discordancias, un 20% sobreexpresó el marcador her2. Conclusiones Teniendo en cuenta la heterogeneidad tanto intratumoral como entre los distintos focos que se presenta en estos tumores múltiples, es importante obtener la mayor información posible sobre la morfología y el perfil inmunohistoquímico.

Estimates of the prevalence of multicentric and multifocal breast tumors is highly variable depending on the different studies analyzed, and this is due largely to the lack of consistency when defining both forms of presentation. For this reason, many authors refer to this type of tumor as multiple breast carcinoma. The tnm (7th edition) defines this presentation as multiple lesions of breast carcinoma present in the same breast synchronously. According to the College of American Pathologists (cap), biological characterization of the lesion of the largest tumor is sufficient, unless discrepancies between the histological tumor types or degrees are presented. Although the strategy of evaluating a single lesion in this regard, has clear advantages in cost and viability, breast cancer is considered itself an heterogeneous disease, and following the recommendations previously expressed, it would be assuming that these type of multiple tumors have a homogeneous biological behavior. Therefore, in this study the biological behavior (er, pr, her2 and Ki-67) is analyzed in each tumor focus, to determine whether to follow the recommendations currently in force, we would not be sub-treatment a group of our patients.

Genetic analysis of resistance to ticks, gastrointestinal nematodes and Eimeria spp. in Nellore cattle.

The aim of the present study was to obtain genetic parameters for resistance to ticks, gastrointestinal nematodes (worms) and Eimeria spp. in Nellore cattle, analyze the inclusion of resistance traits in Nellore breeding programs and evaluate genetic selection as a complementary tool in parasite control programs. Counting of ticks, gastrointestinal nematode eggs and Eimeria spp. oocysts per gram of feces totaling 4270; 3872 and 3872 records from 1188; 1142 and 1142 animals, respectively, aged 146 to 597 days were used. The animals were classified as resistant (counts equal to zero) or susceptible (counts above zero) to each parasite. The statistical models included systematics effects of contemporary groups and the mean trajectory. The random effects included additive genetic effects, direct permanent environmental effects and residual. The mean trajectory and random effects were modeled with linear Legendre polynomials for all traits except for the mean trajectory of resistance to Eimeria spp., which employed the cubic polynomial. Heritability estimates were of low to moderate magnitude and ranged from 0.06 to 0.30, 0.06 to 0.33 and 0.04 to 0.33 for resistance to ticks, gastrointestinal nematodes and Eimeria spp., respectively. The posterior mean of genetic and environmental correlations for the same trait at different ages (205, 365, 450 and 550 days) were favorable at adjacent ages and unfavorable at distant ages. In general, the posterior mean of the genetic and environmental correlations between traits of resistance were low and high-density intervals were large and included zero in many cases. The heritability estimates support the inclusion of resistance to ticks, gastrointestinal nematodes and Eimeria spp. in Nellore breeding programs. Genetic selection can increase the frequency of resistant animals and be used as a complementary tool in parasite control programs.

Tick-borne encephalitis virus, Kyrgyzstan.

Tick-borne encephalitis virus (TBEV) is an emerging pathogen in Europe and Asia. We investigated TBEV in Kyrgyzstan by collecting small mammals and ticks from diverse localities and analyzing them for evidence of TBEV infection. We found TBEV circulating in Kyrgyzstan much farther south and at higher altitudes than previously reported.

[Spastic hip surgery in children]. / Cirugía de cadera espástica en niños.

BACKGROUND: Spasticity in patients with infantile cerebral palsy may lead to progressive subluxation and/or hip dislocation. MATERIAL AND METHODS: Retrospective, cross-sectional trial of a cohort of patients with infantile cerebral palsy who underwent subtrochanteric osteotomy of the hip at the Shriner's Hospital for children in Mexico City, with a 5-year follow-up. X-ray evaluation was conducted pre- and postoperatively and at the 5-year follow-up using the Settecerri classification. RESULTS: Twenty cases were analyzed; mean age was 8.8 years. They included spastic quadriplegia, spastic diplegia, spastic paraplegia. Good results accounted for 50%, fair 30% and poor 20%. Good results in patients with quadriplegia represented 50%, with diplegia 25%, and with paraplegia 75%. Among patients undergoing single osteotomy, good results were 28%, fair 57%,and poor 14%; among those undergoing osteotomy plus cotyloplasty, good results were 63%, fair 9%, and poor 27%. Results with osteotomy plus soft tissues were good and fair in 50% of patients. DISCUSSION: Spasticity and its effects are always present, regardless of surgery, treatment or no treatment; this is the reason for the recurrence of deformities or articular problems of the hip. The benefit of treatment cannot be denied despite spasticity. CONCLUSIONS: The best results were seen among the youngest patients with spastic diplegia and spastic paraplegia. Osteotomy as a single procedure is insufficient and therefore cotyloplasty is recommended.

[Clinical arthroscopic correlation of knee lesions in pediatric patients]. / Correlación clínico-artroscópica en lesiones de rodilla en pacientes pediátricos.

INTRODUCTION: Intraarticular injuries of pediatric patients have a different approach to that of adult patients. Part of this problem lies in minimizing children's symptoms by parents as well as physicians thinking they are less prone to injuries that require surgical management. Arthroscopy has helped in diagnosing these injuries, but the use of this method could be over used. We present a correlation of clinical diagnosis and arthroscopic findings. MATERIAL AND METHODS: We conducted a transversal retrolective study in "Hospital Central Sur Petroleos Mexicanos". We compared clinical diagnoses vs. arthroscopic findings in a group of patients younger than 18 years operated on from June 1995 to February 2005. RESULTS: One hundred and thirty one patients were operated on, and subdivided in two groups: younger that 13 years and older that 13 years, 42% preoperative and postoperative diagnoses correlated in the first group, and 46% for the second group. CONCLUSION: Arthroscopic surgery is useful in achieving better diagnostic precision, as well as it gives us the opportunity to specifically treat knee injuries in pediatric patients.

[Lumbar osteochondroma and radicular compression. A case report]. / Osteocondroma de lámina lumbar y compresión radicular. Reporte de un caso.

UNLABELLED: Most cartilage forming tumors are benign and rarely affect the spinal canal, their principal location is in humerus metaphysis, femur and tibia. They represent 2% of all tumors and 2.6% of the benign tumors of the spine, usually located at the cervical spine. It is speculated that the secondary ossification center may be aberrant cartilaginous tissue that causes the formation of osteochondroma. From 1 to 4% of osteochondromas involve the spine and are commonly included in the posterior elements of the vertebrae and if located near neurological structures causing irritation and spinal compression is rare but potentially catastrophic. The average age of clinical onset is at the 2nd and 3rd decade of life. CASE PRESENTATION: 50-year-old male who began his illness four years ago with pain in the lumbar region with right leg paresthesias, muscle strength 4/5 in the dermatomes L4 and L5, pain was increasing in intensity and frequently. The complete cure was to remove the exostosis of the lamina of right side of L4 with projection to the medullary canal and origin of the contact with the root of L4. We performed: clinical history, physical examination, X-rays, magnetic resonance imaging, electromyography, histology. It was performed: total removal of the tumor effectively and symptoms disappeared. As the spinal osteochondromas are rare and tend to occur in young adults.

Coherent control of population transfer in Rydberg atoms via chirped microwave pulses.

We present a comprehensive and ab initio nonperturbative investigation of the coherent population transfer among the 3D high-lying Rydberg hydrogen and alkali atomic states via linearly polarized chirped microwave pulses. The time-dependent Schrödinger equation for the dynamical evolution of Rydberg atoms is accurately and efficiently solved by means of the time-dependent generalized pseudospectral method. For atomic H, the population transfer from n = 35 to 30 with nearly 100% efficiency is achieved by means of the sequential two-photon Deltan = -1 transitions. The calculation fully utilizes all of the available orbital angular momentum l states for a given n, and the interference pattern and population evolution dynamics of individual l states are analyzed in detail. It is shown that the coherent control of the population transfer from the high n to the low n states can be accomplished by the optimization of the chirping parameters and microwave field strength. Similar analysis is performed for the Na atom, where the alkali atomic structure is described by an accurate model potential. We found that while the global population transfer pattern is qualitatively similar, there are significant differences in the dynamical response of atomic H and Na to the chirped microwave fields. Due to the degeneracy of the l states (for a given n) in unperturbed atomic H, the population transfer involves significant coupling and interference among a number of low-lying l states. For the case of Na atoms, however, the population transfer from the n to (n - 1) state is dominated by a single channel, namely, from the |n,l = 0> to the |n - 1,l = 0> state.

Información computacional e inteligencia médica artificial. Estado actual y accesibilidad en internet / Computing informatics and artificial medical intelligence: its state at present and its internet accesibility

Se presenta una revisión y análisis de la literatura más relevante sobre informática médica computacional e inteligencia médica artificial, y su disponibilidad en internet al principio del tercer milenio. Se llevó a cabo estudio descriptivo del ciberespacio durante agosto de 2000. Los sistemas referidos están compuestos por bases de datos, motor de inferencia médica y la interfase amigable con el usuario. Las diferentes aproximaciones con las cuales es construido el motor de inferencia médica tienen sus cimientos en la manipulación de información y en conocimientos que coadyuvan a la solución de un problema. La evaluación debe efectuarse sobre la precisión del programa, la naturaleza del sistema, el uso de los datos médicos y la aceptación de los usuarios, la cual depende, entre otras cosas, de la accesibilidad de la interfase amigable. Es necesaria una fuerte integración entre las aplicaciones de la inteligencia médica artificial y los sistemas de información en salud, resaltando las guías computacionales para el soporte de nuevos paradigmas en cuidado a la salud, la competencia profesional fundamentada en la medicina basada en evidencias y el costo-beneficio. Los cambios profundos en las telecomunicaciones y el desarrollo de los sistemas de inteligencia médica artificial e informática médica, necesitan más atención por parte de la comunidad médica científica para lograr una excelente competencia profesional y calidad en la atención del paciente.

Osteorregeneración: coagulite vs hidroxiapatita vs coagulite-hidroxiapatita en lesiones en maxilares de rata, con tomografía axial computarizada y microscopía electrónica de barrido / Osteoregeneration: coagulite vs hydroxyapatite vs coagulite hydroxyapatite in experimental maxillary injuries in rats, as determined by computarized tomography and electron microscopy

El propósito de este estudio fue evaluar la osteorregeneración de lesiones provocadas en maxilares de ratas Wistar, acelerando el proceso por medio de biomateriales simples y combinados. Se implantó coagulite o hidroxiapatita o coagulite-hidroxiapatita en seis ratas Wistar sanas, machos, de 24 semanas de edad y se siguieron los siguientes procedimientos según las normas de bioética en animales de experimentación: se anestesiaron con zolazepam y tiletamina (0.4 ml), abordaje quirúrgico con la técnica Semi-Newman; se les realizaron cuatro perforaciones en la maxila: dos del lado derecho y dos del izquierdo, con fresa redonda de carburo de 2 mm de di metro. Posteriormente se implantaron los biomateriales en cada una de las perforaciones. A (coagulite) maxilar derecho en la unión cigom tica-maxilar; B (hidroxiapatita), entre el primer y segundo molares derechos, C (coagulite-hidroxiapatita) en la unión cigom tica-maxilar izquierda y D (control) entre el primer y segundo molares izquierdos. Estas lesiones fueron analizadas por tomografía axial computarizada, microscopía electrónica de barrido y an lisis histológico. Para los valores densitométricos obtenidos a las 3, 6, 9 y 12 semanas de implantados los biomateriales, el an lisis de varianza (ANOVA) mostró diferencia estadística significativa con una p < 0.018. En el análisis de superficie (lleno de las cavidades), a 3, 6, 9, 12 y 15 semanas se utilizó la prueba de Kruskal-Wallis, ésta mostró una diferencia estadística significativa con una p < 0.03. El análisis histológico mostró que el coagulite tiene el mejor proceso de morfodiferenciación de las mmicroestructuras en la ingeniería tisular. Se concluye que la tomografía axial computarizada es una alternativa para evaluar osteorregeneración in vivo y que el coagulite es más eficaz en osteorregeneración que la hidroxiapatita y que el coagulite-hidroxiapatita de lesiones maxilares en ratas Wistar.

Dolor por torniquete neumático. Anestesia espinal versus extradural con bupivacaína en cirugía ortopédica de extremidad inferior / Pain Induced by pneumatic tourniquet. Spinal versus extradural anesthesia in orthopedic surgery of lower limbs

El propósito de esta investigación clínica comparativa experimental fue corroborar la usencia de dolor por torniquete neumático durante la anestesia espinal con bupivacaína simple al 0.5 por ciento, en pacientes sometidas a cirugía ortopédica de extremidad inferior, en un Hospital de urgencias Traumatológicas. El rango de edad en los setenta pacientes estudiados fue de 18-90 años, divididos en dos grupos, Grupo A (problema, n=35), anestesia espinal con bupivacaína simple al 0.5 por ciento (15 mg) y Grupo B (control, n=35), anestesia extradural con el mismo anestésico (75-100 mg). Sesenta y nueve pacientes requirieron el procedimiento quirúrgico utilizando un torniquete neumático (Grupo A, n=35; Grupo B, n=34) y dos del grupo B (n=33), del tratamiento estadístico final. No se presentó dolor por torniquete en los pacientes del grupo espinal; en el grupo extradural, diecisiete lo presentaron (51.5 por ciento), ameritando sedación ó anestesia general (p=0.0235). No hubo complicaciones en relación con el procedimiento anestésico en ninguno de los pacientes. En conclusión, la anestesia espinal con bupivacaína simple al 0.5 por ciento previene el dolor por torniquete en pacientes sometidos a cirugía ortopédica de extremidad inferior

Anestesia espinal en ancianos para cirugía ortopédica de miembro inferior: estudio comparativo con bupivacaína simple al 0.5 por ciento y lidocaína al 5 por ciento / Spinal anesthesia for ortophedic surgery in the elderly. A compartive study between bupivacaine 0.5 por ciento y lidocaina al 5 por ciento

Se comparan los efectos de la Bupivacaina simple al 0.5 por ciento y Lidocaína al 5 por ciento por vía espinal en ancianos para cirugía ortopédica del miembro inferior. Se realizó un estudio prospectivo en dos grupos de 33 pacientes cada uno, de 60 años o mayores con objeto de valorar comparativamente los cambios en la tensión arterial sistólica y la frecuencia cardiaca durante la inducción de la anestesia, estableciendo como respuesta inadecuada: una disminución de 30 por ciento o más en la tensión arterial sistólica y aumento o disminución de 20 latidos o más por minuto en la frecuencia cardiaca de la cifras basales. Los resultados muestran que la Bupivacaína tiene mayor seguridad que la Lidocaína con respecto a la tensión arterial sistólica, mientras que ambas son igual de seguras con respecto a la frecuencia cardiaca. Se concluye que la Bupivacaína simple al 0.5 por ciento es adecuada para cirugía ortopédica de miembros inferiores en ancianos