Competitive fitness and stability of ammonium-excreting Azotobacter vinelandii strains in the soil.

Non-symbiotic N2-fixation would greatly increase the versatility of N-biofertilizers for sustainable agriculture. Genetic modification of diazotrophic bacteria has successfully enhanced NH4+ release. In this study, we compared the competitive fitness of A. vinelandii mutant strains, which allowed us to analyze the burden of NH4+ release under a broad dynamic range. Long-term competition assays under regular culture conditions confirmed a large burden for NH4+ release, exclusion by the wt strain, phenotypic instability, and loss of the ability to release NH4+. In contrast, co-inoculation in mild autoclaved soil showed a much longer co-existence with the wt strain and a stable NH4+ release phenotype. All genetically modified strains increased the N content and changed its chemical speciation in the soil. This study contributes one step forward towards bridging a knowledge gap between molecular biology laboratory research and the incorporation of N from the air into the soil in a molecular species suitable for plant nutrition, a crucial requirement for developing improved bacterial inoculants for economic and environmentally sustainable agriculture. KEY POINTS: • Genetic engineering for NH4+ excretion imposes a fitness burden on the culture medium • Large phenotypic instability for NH4+-excreting bacteria in culture medium • Lower fitness burden and phenotypic instability for NH4+-excreting bacteria in soil.

Phylogenomics of Tetraopes longhorn beetles unravels their evolutionary history and biogeographic origins.

Tetraopes longhorn beetles are known for their resistance to milkweed plant toxins and their coevolutionary dynamics with milkweed plants (Asclepias). This association is considered a textbook example of coevolution, in which each species of Tetraopes is specialized to feed on one or a few species of Asclepias. A major challenge to investigating coevolutionary hypotheses and conducting molecular ecology studies lies in the limited understanding of the evolutionary history and biogeographical patterns of Tetraopes. By integrating genomic, morphological, paleontological, and geographical data, we present a robust phylogeny of Tetraopes and their relatives, using three inference methods with varying subsets of data, encompassing 2-12 thousand UCE loci. We elucidate the diversification patterns of Tetraopes species across major biogeographical regions and their colonization of the American continent. Our findings suggest that the genus originated in Central America approximately 21 million years ago during the Miocene and diversified from the Mid-Miocene to the Pleistocene. These events coincided with intense geological activity in Central America. Additionally, independent colonization events in North America occurred from the Late Miocene to the early Pleistocene, potentially contributing to the early diversification of the group. Our data suggest that a common ancestor of Tetraopini migrated into North America, likely facilitated by North Atlantic land bridges, while closely related tribes diverged in Asia and Europe during the Paleocene. Establishing a robust and densely sampled phylogeny of Tetraopes beetles provides a foundation for investigating micro- and macroevolutionary phenomena, including clinal variation, coevolution, and detoxification mechanisms in this ecologically important group.

Reconstrucción de ligamento cruzado anterior con isquiotibiales manteniendo su inserción tibial / ACL reconstruction with hamstring autograft maintaining tibial insertion

Introducción: La no desinserción tibial de semitendinoso-recto interno (ST-RI) parece constituir una opción para evitar la necrosis avascular en el proceso de ligamentización. El objetivo de nuestro trabajo es hacer una comparación entre ST-RI desinsertado versus ST-RI no desinsertado. Materiales y métodos: estudio comparativo, prospectivo, randomizado, doble ciego, para el que se formaron dos grupos. El grupo de estudio, conformado por treinta y ocho pacientes con plástica de LCA sin desinserción tibial de ST-RI; el grupo de control, de treinta y nueve pacientes con desinserción tibial. Se realizaron evaluaciones de RM a los seis meses del postoperatorio, se evaluaron el Coeficiente Señal ruido (CS) y la orientación del neoligamento en planos sagital, coronal y axial. La valoración clínica, a través de IKDC, Tegner Lysholm y KT-1000, fue efectuada por médicos en forma ciega.Resultados: el CS valorado por RM a los seis meses mostró diferencias significativas entre el grupo de estudio (14.4) y el de control (24.9) con un valor p <0.001. No existieron diferencias en cuanto a la orientación del injerto entre ambos grupos, ni en el plano sagital, coronal, ni axial. En cuanto al IKDC y Tegner Lysholm, sin diferencias entre grupos a los nueve meses. En el KT-1000 tampoco se encontraron diferencias entre grupos (p = 0.518).Discusión: la no desinserción tibial de ST-RI es una opción válida que podría evitar la fase de necrosis avascular de la ligamentización. Nuestros resultados, sustentados en RM, nos estimulan a utilizarla como una opción con cierta ventaja biológica.

Introduction: Non disinsertion of hamstring autograft tendons may result in avoiding cellular necrosis at the early stage of ligamentization process. The aim of this study was to compare between disinserted vs non disinserted hamstring autograft. Materials and methods: in this prospective, double-blind, randomised controlled trial, two groups were created. In the study group, hamstring tendon retraction (n=39) was performed. In the control group, maintaining tibial insertion (n=38) harvesting technique was used. Patients were evaluated with MRI after six months of follow-up. Graft maturity was evaluated with the signal-to-noise quotient (SNQ) and graft direction and orientation with sagittal, coronal, and axial views. Clinical outcomes were assessment of IKDC, Tegner-Lisholm activity level score and KT-1000 evaluation from a blind ortopaedic surgeon.Results: signal-to-noise quotient (SNQ) was significantly lower in non disinserted hamstring group (study group 14.4 vs control group 24.9-p = 0.001). There were no differences in graft direction between both groups. KT-1000 measurements showed no difference, the same as clinical outcomes assessment of IKDC and Tegner-Lisholm scores.Discussion: non disinserting hamstring tendons autograft is a valid option and may avoid the necrosis phase in ligamentization process. Our results, sustained on MRI imaging encourage us to use it with some biological advantage.

Seudoartrosis recalcitrante de húmero: técnica de reconstrucción biológica / Recalcitrant humeral nonunion: biological reconstruction technique

Introducción: La incidencia de seudoartrosis en las fracturas de húmero tratadas de forma conservadora es del 2-10%, y del 15% en aquellas operadas. La definición de seudoartrosis recalcitrante es aún tema de debate. El objetivo es comunicar los resultados de una serie de pacientes con seudoartrosis recalcitrante de húmero tratados con osteosíntesis estable y reconstrucción biológica con aloinjerto mediante una nueva técnica de montaje. Materiales y Métodos: La serie incluyó a 33 pacientes evaluados entre 2012 y 2021, 20 mujeres y 13 hombres (edad promedio 65.4 años). El tiempo de evolución de la seudoartrosis recalcitrante era de 33.3 meses. Todos tuvieron un seguimiento promedio de 33.2 meses. Resultados: Treinta y dos de los 33 pacientes tratados con esta técnica (97%) tuvieron una consolidación completa y uno, una parcial. El período de consolidación promedio fue de 4.6 meses y el de osteointegración completa del aloinjerto, de 8.1 meses. Para la evaluación funcional se consideraron la escala analógica visual, el puntaje ASES, el puntaje de Constant-Murley y los arcos de movilidad del codo. Conclusiones: El manejo de las seudoartrosis recalcitrantes de húmero sigue siendo un dilema y un problema no resuelto aún para los cirujanos experimentados. La combinación entre el uso de un material de osteosíntesis específico sumado al aloinjerto óseo fijado con tornillos aumenta considerablemente la estabilidad mecánica, permite una movilidad precoz, y actúa como un andamio osteoinductor y osteoconductor vital para la consolidación. Nivel de Evidencia: IV

Introduction: Nonunion of the humeral shaft occurs in between 2% and 10% of non-surgically treated fractures and up to 15% of fractures treated with initial open reduction and internal fixation. The definition of recalcitrant nonunion is still under debate. The purpose of this study is to present the outcomes of a series of patients with recalcitrant pseudarthrosis of the humerus who were treated with stable osteosynthesis combined with biological reconstruction using allograft utilizing a novel surgical approach. Materials and Methods: The series included 33 patients treated between 2012 and 2021. 20 women and 13 men, with a mean age of 65.4 years. The evolution time of recalcitrant pseudarthrosis was 33.3 months. The mean follow-up was 33.2 months. Re-sults: Out of a total of 33 patients treated with this technique, 32 (97%) achieved a complete consolidation and one patient had a partial consolidation. The average consolidation period was 4.6 months and the complete osseointegration of the allograft was 8.1 months. For the functional evaluation, the visual analog scale (VAS), ASES score, Constant score and elbow motion arcs were taken into account. Conclusions: Even among experienced surgeons, the treatment of recalcitrant pseudarthrosis of the humerus remains an obstacle and an unsolved challenge. The use of a specialized osteosynthesis material added to a bone allograft fixed with screws significantly increases mechanical stability, allowing early range of motion, and works as an osteoinductive and osteo-conductive scaffold, all of which are essential for consolidation. Level of Evidence: IV

Basaloid squamous cell carcinoma with prominent shadow (ghost) cell differentiation. An unreported neoplasm of the parotid gland.

Basaloid squamous cell carcinoma (BSCC) is an aggressive type of squamous cell carcinoma (SCC) predominant in the upper aerodigestive tract. To our knowledge, only one case of that tumor has been previously described in the parotid gland. Shadow (ghost) cell differentiation (SCD) is a specialized form of keratinization characteristic of pilomatricoma, and other skin tumors with follicular differentiation. SCD has also been described infrequently in some visceral carcinomas and rarely in the minor salivary glands. Recently, an SCC with prominent SCD has been reported in the parotid. We report for the first time the case of parotid BSCC with prominent SCD in an 87-year-old man. He was admitted due to the appearance in the last few months of a mass, painful on palpation, in the left parotid region. Imaging studies and tru-cut biopsies indicated the need for surgical removal. A left superficial parotidectomy, including the branch of the cervicofacial nerve, was performed. The BSCC showed predominance (62%) of SCD. Immunohistochemically, the basaloid cells were positive for ß-catenin, pan-cytokeratin (pan-CK) AE1∕AE3, CK19, high-molecular-weight CK (HMWCK), p63, p40, and cluster of differentiation 10 (CD10) in a diffuse pattern. No signs of recurrence or metastasis were observed four months after surgery. The main differential diagnoses include nuclear protein in testis (NUT) carcinoma, adamantinoma-like Ewing sarcoma, embryonal carcinoma, and basal cell adenocarcinoma of the solid type. SCD in BSCC of the parotid should be recognized to avoid misdiagnosis, especially in small samples. Although rare, BSCC with SCD should be added to the list of tumors that may originate in the parotid gland.

Scientometric Analysis of Hiking Tourism and Its Relevance for Wellbeing and Knowledge Management.

Hiking is a sports activity that takes place in the natural environment. From the point of view of well-being, it is an aerobic activity that prevents and improves cardiovascular diseases. According to data provided by the United Nations, within the framework of the International Year of Mountains, mountain tourism represents around 15% to 20% of total world tourism revenue. This approach aims to critically analyze the scientific production on trail tourism (HT) with contributions from authors from around the world from 1991 to 2022, in order to respond to the connection between this research, knowledge management and the sustainable development of the industry. Key knowledge contributions are examined using a scientometric approach as a method (spatial, production, impact, and relational) based on registry data stored in the Web of Science (JCR and ESCI). Regarding the results, there has been an increase in scientific production in the last decade, which is manifested in the quality of the publications.

Uso de aloinjerto vs. autoinjerto en la reconstrucción del ligamento cruzado anterior. Seguimiento a 4 años / Allograft vs. autograft in ACL reconstruction. Follow-up of 4 years

Si bien el autoinjerto ha sido tradicionalmente el estándar de oro para la reconstrucción del ligamento cruzado anterior (RLCA), el uso de aloinjerto se ha incrementado en los últimos años. Aunque numerosos estudios han demostrado que los aloinjertos irradiados se asocian con un aumento de las tasas de fracaso, algunos autores sostienen excelentes resultados después de una RLCA con aloinjertos no irradiados. Objetivo: Comparar resultados clínicos medidos en términos de escalas funcionales y de actividad, y las diferencias en estabilidad anteroposterior (KT 1000) y rotacional (Pivot Shift), entre pacientes intervenidos de una plástica primaria de LCA en nuestro centro. Materiales y Método: Entre 2006 y 2011, se realizaron 75 RLCA primarias (en 25 casos se utilizó aloinjerto Hueso-Tendón–Hueso [HTH] no irradiado y en 50 casos autoinjerto). Se les realizó las escalas funcionales de Lysholm y Tegner y la escala del IKDC. Además se evaluó clínicamente el desplazamiento anteroposterior con un artrómetro (KT1000) y se constató la presencia de pivot shift en busca de inestabilidad rotacional. Se midió el rango de movilidad postoperatorio al mes, 2 y 6 meses. Resultados: El seguimiento promedio fue de 4,2 años (2 a 6 años) para el grupo ALO y 5,6 para el grupo AUTO (2 a 9 años). No existieron diferencias significativas en cuanto a las escalas funcionales, ni a las pruebas de inestabilidad (KT1000 y pivot shift). Existió una complicación (4%) para el grupo ALO que fue una infección profunda que requirió revisión del injerto y en el grupo AUTO hubo 5 complicaciones (2 hipoestesias en zona medial y 3 pacientes con molestias al arrodillarse o realizar sentadillas profundas). Conclusión: Creemos que la utilización de aloinjerto de hueso-tendon-hueso en concordancia con la literatura, constituye una opción valedera a la hora de elegir el injerto en pacientes mayores de 40 años o que no tengan una alta demanda...

While autograft has traditionally been the gold standard for anterior cruciate ligament reconstruction (ACLR), the use of allograft has increased in recent years. Although numerous studies have shown that irradiated allografts are associated with increased failure rates, some authors have reported excellent results after a RLCA with nonirradiated allografts. The purpose of this study was to determine whether the use of non-irradiated allograft tissue (ALO) is associated with a worse outcome compared with autografts (AUTO). Materials and Methods: Between 2006 and 2011, 75 primary RLCA (25 BTB allograft and 50 non-irradiated autograft) were performed. We performed functional Lysholm and Tegner activity scales and IKDC score. Furthermore, the anteroposterior displacement was assesed using the KT1000 arthrometer and pivot shift test was done in order to evaluate rotational instability. Postoperative range of motion at month, 2 and 6 months was measured. Results: Mean follow-up was 4.2 years (2-6 years) for the ALO group and 5.6 for the AUTO group (2-9 years). There were no significant differences in the functional scales, or evidence of instability (pivot shift and KT 1000). There was a complication (4%) for the ALO group that was a deep infection requiring ACL revision and in the AUTO group there were 5 complications (2 hypoesthesias and 3 patients presented discomfort when kneeling or performing deep squats). Conclusion: According to the literatura, we believe that the use of BTB allograft, is a valid option when choosing grafting in patients over age 40 or with low demand. Moreover, the use of allograft avoided the high morbidity of the autograft donor site and provided superior esthetic results. Level of evidence: IV. Type of Study: Retrospective...

Lesión del ligamento cruzado anterior: ¿ es la disminución en la movilidad de la cadera un factor predisponente ? / Predisposing factors of hip hypermotility in anterior cruciate ligament injuries

Introducción: La lesion del ligamento cruzado anterior (LCA) es una de las patologias musculoesqueleticas mas frecuentes. Numerosos factores predisponentes han sido identificados intrinsecamente en la articulacion. El objetivo de este trabajo es analizar la relacion existente entre una hipomotilidad de cadera y la presencia concomitante de una lesion de LCA en deportistas recreacionales. Materiales y Método: Se incluyo en forma prospectiva a pacientes deportistas recreacionales entre 18 y 40 anos (48 con una lesion primaria de LCA confirmada por RMN y 53 controles voluntarios). Se midieron ambas rotaciones en decubito supino y los resultados fueron analizados estadisticamente con la prueba de t test. Resultados: Se analizaron los datos y resultaron estadisticamente significativos en cuanto a una disminucion de movilidad en la cadera homolateral a la rodilla afectada por la lesion del ligamento, tanto para la rotacion interna [RI] (p=0.001) como para la rotacion externa [RE] (p=0.016). El analisis comparativo con el grupo control mostro que existe una asociacion entre rotura de LCA y una hipomotilidad de cadera a expensas en mayor medida de una disminucion en la RI (p=0,002), puesto que la comparacion de la RE en ambos grupos no resulta estadisticamente significativa (p=0.936). Conclusión: Existe una fuerte asociacion entre la lesion del LCA y hipomotilidad de la cadera, principalmente a expensas de la rotacion interna en deportistas recreacionales. No solo encontramos esta asociacion entre voluntarios y pacientes con la lesion sino tambien en el miembro contralateral a la lesion LCA. Por tal motivo creemos de vital importancia el cribado de factores de riesgo para asi implementar planes de prevencion. Nivel de Evidencia: II. Tipo de Estudio: Prospectivo...(AU)

Introduction: Numerous intrinsic predisposing factors have been identified within the knee joint in ACL injuries. However, several studies have showed the influence of the hip on the knee biomechanics. The aim of this paper is to analyze the relationship between a hip hypomotility and the concomitant presence of an ACL injury in recreational athletes. Method: We prospectively evaluated 48 recreational athletes with ACL injury confirmed with MRI and 53 volunteer controls without ACL injuries between 18 and 40 years of age. Internal rotation [IR] and external rotation [ER] were measured and analyzed. Results: A significant decrease in hip range of motion was found in the ipsilateral hip, both for IR (p=0.001) and ER (p=0.016). Comparative analysis with the control group showed an association between ACL tear and hypomotility hip mainly because of IR lessening (p=0.002), since the comparison of the ER in both groups was not statistically significant (p=0.936). Conclusion: There is a strong association between ACL injury and hip hypomotility , not only but mainly due to a decrease in IR. Moreover, we found not only this association between volunteers and patients, but in the same patient compared to the unaffected side. Therefore, we believe that is especially important to identify risk factors in order to prevent these lesions. Level of Evidence: IV. Type of study: Case Series. Retrospective...(AU)

Lesión del ligamento cruzado anterior: ¿ es la disminución en la movilidad de la cadera un factor predisponente ? / Predisposing factors of hip hypermotility in anterior cruciate ligament injuries

Introducción: La lesion del ligamento cruzado anterior (LCA) es una de las patologias musculoesqueleticas mas frecuentes. Numerosos factores predisponentes han sido identificados intrinsecamente en la articulacion. El objetivo de este trabajo es analizar la relacion existente entre una hipomotilidad de cadera y la presencia concomitante de una lesion de LCA en deportistas recreacionales. Materiales y Método: Se incluyo en forma prospectiva a pacientes deportistas recreacionales entre 18 y 40 anos (48 con una lesion primaria de LCA confirmada por RMN y 53 controles voluntarios). Se midieron ambas rotaciones en decubito supino y los resultados fueron analizados estadisticamente con la prueba de t test. Resultados: Se analizaron los datos y resultaron estadisticamente significativos en cuanto a una disminucion de movilidad en la cadera homolateral a la rodilla afectada por la lesion del ligamento, tanto para la rotacion interna [RI] (p=0.001) como para la rotacion externa [RE] (p=0.016). El analisis comparativo con el grupo control mostro que existe una asociacion entre rotura de LCA y una hipomotilidad de cadera a expensas en mayor medida de una disminucion en la RI (p=0,002), puesto que la comparacion de la RE en ambos grupos no resulta estadisticamente significativa (p=0.936). Conclusión: Existe una fuerte asociacion entre la lesion del LCA y hipomotilidad de la cadera, principalmente a expensas de la rotacion interna en deportistas recreacionales. No solo encontramos esta asociacion entre voluntarios y pacientes con la lesion sino tambien en el miembro contralateral a la lesion LCA. Por tal motivo creemos de vital importancia el cribado de factores de riesgo para asi implementar planes de prevencion. Nivel de Evidencia: II. Tipo de Estudio: Prospectivo...

Introduction: Numerous intrinsic predisposing factors have been identified within the knee joint in ACL injuries. However, several studies have showed the influence of the hip on the knee biomechanics. The aim of this paper is to analyze the relationship between a hip hypomotility and the concomitant presence of an ACL injury in recreational athletes. Method: We prospectively evaluated 48 recreational athletes with ACL injury confirmed with MRI and 53 volunteer controls without ACL injuries between 18 and 40 years of age. Internal rotation [IR] and external rotation [ER] were measured and analyzed. Results: A significant decrease in hip range of motion was found in the ipsilateral hip, both for IR (p=0.001) and ER (p=0.016). Comparative analysis with the control group showed an association between ACL tear and hypomotility hip mainly because of IR lessening (p=0.002), since the comparison of the ER in both groups was not statistically significant (p=0.936). Conclusion: There is a strong association between ACL injury and hip hypomotility , not only but mainly due to a decrease in IR. Moreover, we found not only this association between volunteers and patients, but in the same patient compared to the unaffected side. Therefore, we believe that is especially important to identify risk factors in order to prevent these lesions. Level of Evidence: IV. Type of study: Case Series. Retrospective...

Dental implants and osteomyelitis in a patient with osteopetrosis.

Osteopetrosis (OP) is a rare genetic metabolic bone disorder characterized by osteoclast dysfunction impairing bone resorption. Together with normal osteoblastic activity this dysfunction promotes intense bone sclerosis with reduction of marrow spaces as well as bone turnover. Maxillofacial complications are common after tooth extraction. Osteomyelitis (OM) of the mandible occurs in around 10% of the cases with OP. The purpose of this paper is to report the fi rst case of OP treated with dental implants, and to describe the protocol used to treat OM that developed after failure of one implant. The treatment of OM included long-term use of antibiotics and marginal bone resection with a piezoelectric device. Similar cases to confirm the efficacy of this treatment are required.

Spectral sensitivities of photoreceptors and their role in colour discrimination in the green-backed firecrown hummingbird (Sephanoides sephaniodes).

We studied the photopic spectral sensitivity in the green-backed firecrown, Sephanoides sephaniodes, a South American hummingbird, and its possible ecological relationship with preferred flowers and body colouration. Avian colour vision is in general tetrachromatic with at least four types of cones, which vary in sensitivity from the near ultraviolet (UV) to the red wavelength range. Hummingbirds represent an important family of birds, yet little is known about their eye sensitivity, especially about the role of photoreceptors and their oil droplet complements. The photopic electroretinogram shows a main sensitivity peak at 560 nm and a secondary peak in the UV, and may be explained by the presence of four single cones (lambda max at approximately 370, 440, 508 and 560 nm), and a double cone (lambda max at 560 nm) screened by oil droplets. The flowers preferred by the firecrown are those in which the red-green wavelength region predominates and have higher contrast than other flowers. The crown plumage of males is highly iridescent in the red wavelength range (peak at 650 nm) and UV; when plotted in a high-dimensional tetrachromatic space, it falls in a "red + UV" purple hue line, suggesting a potential significant communication signal for sexual differentiation.

Programa de Psiquiatría ambulatoria (PPA) de la Comuna Til Til en el marco de la psiquiatría comunitaria / Psychiatry program in Til Til commune in the community psychiatry framework

En el presente trabajo se muestran los fundamentos técnicos, organización, puesta en marcha y evolución de un Programa de Psiquiatría en la Comuna de Til Til, inserto en el COSAM (Centro Comunitario de Salud Mental y Familiar) de la mencionada Comuna. Esta iniciativa de salud surge en el marco de posibilitar que los usuarios reciban atención psiquiátrica en su comuna de residencia, junto al trabajo de psicólogos, terapeuta ocupacional, asistentes sociales, monitores de salud mental y profesionales de salud general de la comuna, es decir, un trabajo de equipo en que cada uno de los integrantes se articula armónicamente proporcionando finalmente una atención global al usuario, evitando largos y costosos desplazamientos al Instituto Psiquiátrico, único centro en donde el usuario podía recibir atención especializada previo a la instalación de este programa, reduciendo descompensaciones y hospitalizaciones y generando en la comunidad una nueva actitud hacia el portador de alguna patología psiquiátrica severa.

Tumor estromal de colon fistulizado a pleura: GIST / Colon stromal tumor fistulized to pleura: GIST

Los tumores estromales gastrointestinales, GIST, son neoplasias infrecuentes que corresponden al 1 por ciento de todos los tumores gastrointestinales. Surgen de las células localizadas en las paredes del sistema gastrointestinal y siguen diversos caminos de diferenciación celular. Se presenta el caso de un paciente de sexo masculino, de 30 años de edad, que presentó un tumor del ángulo esplénico del colon fistulizado a hemitórax izquierdo y complicado con empiema pleural. Se realizó hemicolectomía izquierda con anastomosis término-terminal en dos planos, aseo y decorticación pleural mediante videotoracoscopia. Se operó primero por laparotomía encontrando un tumor de 5 cm en el ángulo esplénico del colon fistulizado hacia el hemidiafragma izquierdo. Se efectuó resección de 30 cm de colon con anastomosis término-terminal. Una vez realizada la laparotomía, se procedió a practicar aseo y decorticación pleural por video toracoscopia izquierda. El diagnóstico histopatológico definitivo concluyó tumor estromal gastrointestinal con diferenciación mixta neural y muscular con baja tasa mitótica. El paciente evoluciona en buenas condiciones siendo dado de alta a los 10 días postoperatorio. En último control en noviembre 2001 TAC toracoabdominal sin evidencias de recidiva

Hemoptisis masiva en embarazadas: una presentación infrecuente de la linfangioleiomiomatosis / Massive hemoptysis in pregnancy: an infrequent presentation of lymphangioleiomyomatosis

Se presenta el caso de una paciente de 36 años, que ingresa al hospital cursando un embarazo fisiológico de 32 semanas, por cuadro hemoptisis masivas (> 700 ml/24 horas) asociadas a disnea, con leve inestabilidad hemodinámica. La fibrobroncoscopía mostró sangrando proveniente del segmento posterior del lóbulo superior derecho, sin daño endoluminal. La radiografía de tórax, tomografía y angiografía bronquial fueron normales. La paciente persistió con sangramiento como fue confirmado en una segunda broncospía por lo que optó por la resolución quirúrgica efectuándose una lobectomía superior derecha. El análisis histopatológico de la pieza concluyó el diagnóstico de Linfagioleiomiomatosis (LAM) y el estudio para receptores de estrógenos fue positivo en el tejido analizado. La LAM es una entidad rara de origen desconocido que afecta sólo a mujeres, especialmente en edad fértil, caracterizada por proliferación del músculo lisi a nivel peribronquial, perivascular y perilifática que conduce a la formación de lesiones quísticas, neumotórax recurrente, hemoptisis y quilotórax. La historia natural de la LAM es hacia la progresiva obstrucción al flujo aéreo, que conduce la falla respiratoria progresiva en un plazo impredecible. Las series más recientes comunican una sobrevida a 8-10 años de 79 por ciento. La hipótesis de la dependencia hormonal y efectividad de terapias tales como ooforectomía y progesterona no han sido demostradas en forma sólida, sin embargo, en la actualidad son las alternativas disponibles previo a la decisión de transplante pulmonar

Sobrevida de pacientes con cáncer de esófago sometidos a esofagectomía total torácica / Survival of patients with esophageal carcinoma submitted to total thoracic esophagectomy

Background: Esophageal carcinoma has a dismal prognosis. Several authors have reported a very low survival in Chile. Aim: To report the survival of patients with esophageal carcinoma, subjected to esophageal resection. Material and methods: Analysis of 108 patients subjected to thoracic esophageal resection between 1985 and 1996. Patients were classified according to the location of the tumor and its staging. Results: Eleven patients died in the immediate postoperative period and 90 patients were followed. In 53 the exact cause of death was determined. Global five years survival was 29 percent and median survival was 18 months. Survival was 100 percent in stage I tumors. Adjuvant therapy resulted in a better survival of stage III tumors. Survival of stage IV tumors was worst than stage I to III tumors. There was no survival difference between squamous carcinoma or adenocarcinoma. Tumors located in the superior third of the esophagus had a worst prognosis. Causes of death were mediastinic metastases, local recidivism, pleural or pulmonary metastases and less frequently, brain, bronchial or bone metastases. Conclusions: The survival of these, patients with esophageal carcinoma did not differ from the figures reported abroad

Programa de atención médico-quirúrgica sin transfusiones sanguíneas / Medical-surgical care programme without blood transfusion

UN creciente interés mundial se ha observado con respecto al desarrollo de técnicas y estrategias tendientes a minimizar el uso de sangre y derivados o a precindir de ellos en el curso de la atención médica. Diversos factores se conjungan para ello, los riesgos inherentes a su uso, el mayor conocimiento sobre la fisiopatología de la anemia y del transporte de oxígeno, estrategias innovadoras y el gran desarrollo farmacológico y técnico. Por otro lado personas que por diversas razones deciden abstenerse del uso de sangre en su tratamiento. En esta linea de pensamiento nuestro Hospital desde el año pasado ha instituido un programa de atención médica sin transfusión de sangre. En el primer artículo se reseñan los hechos clínicos y fisiopatológicos en los cuales se basan las políticas de no transfusión y los recursos técnicos y farmacológicos para hacerlo efectivo