Probing Electron Spin Resonance in Monolayer Graphene.

The precise value of the g factor in graphene is of fundamental interest for all spin-related properties and their application. We investigate monolayer graphene on a Si/SiO_{2} substrate by resistively detected electron spin resonance. Surprisingly, the magnetic moment and corresponding g factor of 1.952±0.002 is insensitive to charge carrier type, concentration, and mobility.

Diabetes-accelerated experimental osteoarthritis is prevented by autophagy activation.

OBJECTIVE: Type 2 Diabetes (T2D) is a risk factor for osteoarthritis (OA). Autophagy, an essential homeostasis mechanism in articular cartilage, is defective in T2D and OA. However, how T2D may influence OA progression is still unknown. We aimed to determine how diabetes affects cartilage integrity and whether pharmacological activation of autophagy has efficacy in diabetic mice (db/db mice) with OA. DESIGN: Experimental OA was performed in the right knee of 9 weeks-old C57Bl/6J male mice (Lean group, N = 8) and of 9 weeks-old B6.BKS (D)-Leprdb male mice (db/db group, N = 16) by transection of medial meniscotibial and medial collateral ligaments. Left knee was employed as control knee. Rapamycin (2 mg/kg weight/day) or Vehicle (dimethyl sulfoxide) were administered intraperitoneally three times a week for 10 weeks. Histopathology of articular cartilage and synovium was evaluated by using semiquantitative scoring and synovitis grading systems, respectively. Immunohistochemistry was employed to evaluate the effect of diabetes and Rapamycin on cartilage integrity and OA biomarkers. RESULTS: Cartilage damage was increased in db/db mice compared to Lean mice after experimental OA, while no differences are observed in the control knee. Cartilage damage and synovium inflammation were reduced by Rapamycin treatment of OA-db/db mice. This protection was accompanied with a decrease in MMP-13 expression and decreased interleukin 12 (IL-12) levels. Furthermore, autophagy was increased and cartilage cellularity was maintained, suggesting that mammalian target of rapamycin (mTOR) targeting prevents joint physical harm. CONCLUSION: Our findings indicate that diabetic mice exhibit increased joint damage after experimental OA, and that autophagy activation might be an effective therapy for diabetes-accelerated OA.

[Cutaneous ultrasound and dermal fillers]. / Ecografía cutánea y rellenos dermatológicos.

Requests for fillers or dermatological implants have dramatically increased in dermatology consultations in the last few years, either for the correction of superficial age-related wrinkles and cutaneous creases or to increase the volume of specific areas (cheeks, lips...). Dermatologists are often the first professionals to provide these treatments. Nevertheless, in other situations, the patients have already been treated, and many of them do not know the type of material that has been implanted or may even deny previous treatment, even when evident on clinical examination. In these occasions, cutaneous ultrasound is an effective and reliable tool for the real-time diagnosis of the kind of implant that has been used, its location, and the study of its possible complications.

[Renal xenotransplant. Acute vascular rejection]. / Xenotrasplante renal. El rechazo vascular agudo.

INTRODUCTION AND OBJECTIVES: Organ transplant is nowadays a usual and succesful practice, although with limited application due to the lack of organs. Yearly thousands of patients get access to the waiting list and finally will death while they are waiting for an organ. In the U.S.A., 2005 waiting list for kidneys, heart, liver lung and pancreas was around 94.419. Number of transplants performed was 27.966 and died patients while waiting for an organ, 41.392 (1). Pig xenotransplant is one of the possibilities to ameliorate the lack of organs for transplant. Arrangement of pigs with different genetic modifications generated great expectatives on the use of these organs in clinics. Although preclinical experimental studies with kidneys reached prolonged survivals, these are really insufficient to go on with the clinical appliance. Hyperacute rejection produces destruction of the organ immediately. This problem could be pharmacologically precluded in xeno-transplant. However, acute rejection or vascular rejection usually produces the lost of the implant. New inmunosuppresive schedules delay significantly rejection, but not definitively. Xenotransplant as a therapeutic option introduces important scientific problems, as well as ethical and social. This paper reports a summary of our experience in renal xenotransplant and the management of acute rejection. MATERIAL AND METHODS: Twenty xenotransplants from transgenic pig (hDAF) as donor to babuine as receptor. Average weight of the animals ranged 11.4-75 kgrs and babuines 10-26 kg. Xenograft average weight ranged 39-160 grs. Implant was performed to aorta and cava. Four inmunosupressive schedules were used. RESULTS: Average survival was 7-9 days. Final Histological findings are described. Changes observed were secondary to acute tubular necrosis mixed with changes due to acute rejection. Three grafts were lost due to technical major problems. CONCLUSIONS: Although we have observed some promising results, xenotransplant is a very difficult problem to solve in the long-term. A lot of research is still needed-.

Índice de discapacidad vocal en niños: autoevaluación. Traducción, transculturalización y validación al español de Latinoamérica / Children´s Voice Handicap Index: self-assessment. Translation, transculturalization and validation to Latinoamerican Spanish

Objetivo: Los trastornos de la voz son muy frecuentes en la población pediátrica, entre el 6% y el 23% de todos los niños presentan alguna forma de disfonía. La evaluación de la voz abarca los aspectos perceptuales, análisis acústico, métodos de diagnóstico visual, y cuestionarios que orientan al impacto sobre la calidad de vida. El objetivo de nuestro estudio es realizar la traducción, transculturalización y validación del cuestionario Children Voice Handicap Index (CVHI) a hispanohablantes latinoamericanos. Material y Método: El estudio se realizó en el Hospital Italiano de Buenos Aires, Argentina y en el Hospital de Niños Dr. Luis Calvo Mackenna de Santiago de Chile. Se incluyeron pacientes entre 8 y 15 años de edad. Se tradujo, transculturalizó y validó el CVHI para dicha población. Se realizó el cuestionario en dos grupos de pacientes: un grupo de niños con antecedentes de disfonías, n = 48 y el otro grupo pacientes de control, sin patología de la voz, n = 86. El cuestionario se aplicó a los niños, en presencia de sus cuidadores o padres, con la correspondiente conformidad. Resultados: Se encontró una diferencia significativa entre ambos grupos (p < 0,05) con una confianza interna óptima de 0,98 obtenida mediante alfa de Cronbach y una alta fiabilidad test-retest (correlación de Pearson = 0,96). Conclusión: La validación y transculturalización del CVHI para la población hispanohablante de latinoamérica presentó una adecuada validez y fiabilidad. Complementar la evaluación de la patología vocal con un sencillo cuestionario de auto-rrealización en población pediátrica, constituye una valiosa herramienta que completa el diagnóstico del impacto de la alteración de la voz en la calidad de vida.

Aim: Voice disorders are very common in the pediatric population, since between 6% and 23% of all children present some type of dysphonia. Voice evaluation includes perceptual aspects, acoustic analysis, visual diagnostic methods, and questionnaires that guide the impact on quality of life. The objective of this study is to carry out the translation, transculturalization and validation of the Children Voice Handicap Index (CVHI) questionnaire for Latin American Spanish speakers. Material and Method: The study was conducted at the Italian Hospital in Buenos Aires, Argentina and at the Dr. Luis Calvo Mackenna Children's Hospital in Santiago de Chile, Chile. Patients between 8 and 15 years of age were included. The CVHI was translated, transculturalized, and validated for said population. The questionnaire was carried out in two groups of patients: a group of children with a history of dysphonia, n = 48, and the other group, control patients, without voice pathology, n = 86. The questionnaire was applied to the children, in the presence of their caregivers or parents, with the corresponding consent. Results: A significant difference was found between both groups (p < 0.05) with an optimal internal confidence of 0.98 obtained using Cronbach's alpha and high test-retest reliability (Pearson's correlation = 0.96). Conclusion: The validation and transculturalization of the CVHI for the Spanish-speaking population of Latin America presented adequate validity and reliability. Complementing the evaluation of vocal pathology with a simple self-administration questionnaire in the pediatric population constitutes a valuable tool that completes the diagnosis of the impact of voice alteration on quality of life.

The Role of Adsorbed and Subsurface Carbon Species for the Selective Alkyne Hydrogenation Over a Pd-Black Catalyst: An Operando Study of Bulk and Surface.

The selective hydrogenation of propyne over a Pd-black model catalyst was investigated under operando conditions at 1 bar making use of advanced X-ray diffraction (bulk sensitive) and photo-electron spectroscopy (surface sensitive) techniques. It was found that the population of subsurface species controls the selective catalytic semi-hydrogenation of propyne to propylene due to the formation of surface and near-surface PdCx that inhibits the participation of more reactive bulk hydrogen in the hydrogenation reaction. However, increasing the partial pressure of hydrogen reduces the population of PdCx with the concomitant formation of a ß-PdHx phase up to the surface, which is accompanied by a lattice expansion, allowing the participation of more active bulk hydrogen which is responsible for the unselective total alkyne hydrogenation. Therefore, controlling the surface and subsurface catalyst chemistry is crucial to control the selective alkyne semi-hydrogenation.

Prognostic factors of radiographic progression in early rheumatoid arthritis: a two year prospective study after a structured therapeutic strategy using DMARDs and very low doses of glucocorticoids.

The objective of the study was to analyze the prognostic factors of radiographic progression in a series of patients with early rheumatoid arthritis (RA) after 2 years of therapy with a structured algorithm using disease-modifying antirheumatic drugs (DMARDs) and very low doses of oral glucocorticoids. One hundred and five patients (81% female) with early RA (disease duration <2 years) treated with the same therapeutic protocol using gold salts and methotrexate in a step-up strategy, together with methylprednisolone (4 mg/day), were followed up for 2 years. The outcome variable was radiographic progression after 2 years of DMARD therapy using the modified Larsen method. Clinical, biological, immunogenetic, and radiographic data were analyzed at study entry and after 1 and 2 years of follow-up. Radiographic progression (increase of four or more units in the Larsen score) was observed in 32% of patients after 2 years of follow-up. The percentage of erosive disease increased from 18.3% at baseline to 28.9% at 12 months and 44.6% at 24 months, in spite of a significant improvement in disease activity. New erosions appeared in 33% of patients after 2 years. Several baseline parameters were associated with radiographic progression in the univariate analysis: shared epitope (SE) homozygozity, HLA-DRB*04 alleles, female gender, hemoglobin, erythrocyte sedimentation rate, and anticyclic citrullinated peptide antibodies (anti-CCP). In the multivariate analysis, female gender [odds ratio (OR) 5.5, 95% confidence interval (CI): 1.1-28.2, p = 0.04], DRB1*04 alleles (OR 3.1, 95% CI 1.1-9, p = 0.03) and, marginally, anti-CCP antibodies (OR 3.6, 95% CI 0.9-14.5, p = 0.06), were associated with progression. Female patients with both DRB1*04 alleles and anti-CCP antibodies showed the highest scores in radiographic progression. The presence, but not the titer, of anti-CCP antibodies predicted progression. The positive predictive value of the multivariate model for progression was only 53.9% whereas the negative predictive value was 80.3%. In a series of early RA patients treated with a structured algorithm using DMARDs and very low doses of glucocorticoids, radiographic progression was observed in one third of patients after 2 years. Female gender, DRB1*04 alleles (rather than the SE), and the presence of anti-CCP antibodies at baseline (independently of the titer) were the most important predictors of progression. The utility of these parameters in clinical practice is limited by their relatively low positive predictive value.

[Perforation risk in esophageal endoscopic mucosal resection with ligation: an experimental study with two ligator models]. / Riesgo de perforación en la mucosectomía esofágica con banda: estudio experimental con dos modelos de ligadores.

OBJECTIVE: endoscopic mucosal resection with ligation (EMRL) is considered an efficient, safe method for the treatment of some esophageal, gastric and colorectal tumors. We conducted this study using a porcine model in order to compare the safety of esophageal EMRL with two multiband ligation systems, since many centers only use these ligator models in EMRL (commercialized for varix ligation). METHODS: eight pigs were used, which were submitted to 23 esophageal resections without previous injection. Ten resections were conducted using the Six Shooter Saeed model, and 13 resections used the Speedband Superview Super 7 model. The technique was also compared by making random cuts either above or below the band. RESULTS: five perforations occurred, all of them using the Speedband model. This represents 38.5% of total in the Speedband model group. No perforation occurred when using the Six Shooter model (p = 0.046). On the contrary, no significant differences were found regarding frequency of perforation when cutting above or below the band. CONCLUSIONS: esophageal EMRL using the Speedband model without previous injection leads to perforation in a high percentage of cases in an experimental animal model. Further studies are required to find out whether a previous injection may increase the safety of this technique with this ligator model.

[Molecular biology of the clear cell renal cell carcinoma: principles for a selective treatment]. / Biología molecular del carcinoma de células claras renales: principios para un tratamiento selectivo.

Renal cell carcinoma (RCC) and its most frequent subtype, the clear cell hystology type, has shown resistance to chemotherapy and radiotherapy treatment when disease was already spread in patients. Recently, a huge advance in the molecular biology of this tumor has been performed. This fact allowed a deeper and better knowledge of the disease and the development of new drugs that work against the growth factors involved in tumor origin. In this review article it is summarized the molecular milestones that are involved in the development of clear cell renal cell carcinomas.

Neuropatía laríngea y movimiento paradojal de cuerdas vocales en la edad pediátrica: reporte de un caso / Laryngeal neuropathy and paradoxical vocal fold motion in the pediatric age: case report

Resumen La neuropatía laríngea es una condición de hipersensibilidad, hiperreactividad e hiper-función laríngea secundaria a un desequilibrio entre las aferencias y eferencias laríngeas. La respuesta individual y exagerada frente a diversos gatillantes específicos puede generar síntomas como tos crónica, parestesia laríngea, carraspera, disfonía, estridor, sensación de globus faríngeo, movimiento paradojal de las cuerdas vocales (también conocido como disfunción cordal) y/o laringoespasmo. Existe abundante literatura sobre neuropatía laríngea en adultos, sin embargo, en niños es limitada. El objetivo de este artículo es dar a conocer un caso de neuropatía laríngea en la edad pediátrica y la importancia de su consideración en el enfrentamiento de estos pacientes. Se presenta caso clínico de un paciente de 13 años, con antecedente de cirugía cardiaca reciente, evoluciona con disfonía severa evidenciándose aparente inmovilidad cordal bilateral con resultados discordantes entre nasofibrolaringoscopía y electromiografía laríngea. Posteriormente presenta mejorías en su voz, sin embargo, se agregan otros síntomas laringológicos como carraspera, globus faríngeo y estridor no explicados por causas anatómicas. Se expone la evaluación y abordaje otorrinolaringológico-fonoaudiológico para el caso. Se concluye que el diagnóstico de neuropatía laríngea requiere un alto índice de sospecha clínica ante signos laringológicos sugerentes, debiendo descartarse causas orgánicas y estructurales. El abordaje otorrinolaringológico-fonoaudiológico constituye el pilar terapéutico asociado al uso de neuromoduladores en casos seleccionados.

Abstract Laryngeal neuropathy is a condition of hypersensitivity, hyperresponsiveness and laryngeal hyperfunction secondary to an imbalance between laryngeal afferent and efferent information. The individual and exaggerated response to diverse specific triggers can lead to symptoms such as chronic cough, laryngeal paresthesia, throat clearing, dysphonia, stridor, globus pharyngeus, vocal cord dysfunction, and/or laryngospasm. There is plentiful literature on laryngeal neuropathy in adults, however, in children, it is limited. Here, we present a case report of laryngeal neuropathy in the pediatric age and discuss the importance of its consideration in the approach of these patients. A case of a 13-year-old patient, recently intervened with cardiac surgery that evolves with severe dysphonia is presented. Nasofibrolaryngoscopy shows apparent bilateral vocal fold immobility with discordant results in laryngeal electromyography. Later, his voice improves but other laryngological symptoms appeared, such as throat clearing, globus pharyngeus and stridor, not explained by anatomical causes. The otolaryngological-speech therapy evaluation and approach for the case is exposed. We conclude that for the diagnosis of laryngeal neuropathy, a high index of clinical suspicion is required in the presence of suggestive laryngological symptoms, and organic and structural causes must be previously ruled out. The otorhinolaryngological-logopedic approach constitutes the mainstay of treatment associated with the use of neuromodulators in selected cases.

Análisis descriptivo del índice de discapacidad vocal pediátrico en niños con patología vocal benigna / Descriptive analysis of the pediatric voice handicap index in children with benign vocal fold pathology

Resumen Introducción: La disfonía infantil puede afectar negativamente la autoestima del niño y su calidad de vida relacionada con la voz. Objetivo: Describir los resultados del cuestionario Pediatric Voice Handicap Index (pVHI) en niños con patología vocal benigna. Material y Método: Se diseñó un estudio descriptivo en pacientes con patología vocal benigna entre 3 y 15 años en la Unidad de Voz del Hospital de Niños Dr. Luis Calvo Mackenna entre octubre de 2016 y febrero de 2020. La evaluación se realizó mediante un examen laringoscópico y el cuestionario pVHI para evaluar el impacto en la calidad de vida. Resultados: Se incluyeron 49 pacientes, 35 varones (71,4%) y 14 mujeres (28,6%). La edad media fue de 9,27 años. En el examen laringoscópico, el hallazgo más frecuente fueron los nódulos vocales. La puntuación media total en el pVHI fue de 38,77: 11,67 en la subescala o categoría funcional, 18,59 en la física y 8,42 en la emocional. En la evaluación de pVHI por género no existieron diferencias significativas. Conclusión: La patología vocal benigna en la edad pediátrica ocasiona un impacto negativo en la calidad de vida relacionada con la voz. El cuestionario pVHI es un valioso instrumento para evaluar dicha repercusión.

Abstract Introduction: Childhood dysphonia can negatively affect a child's self-esteem and voice-related quality of life. Aim: To describe the results of the Pediatric Voice Handicap Index (pVHI) questionnaire in children with benign vocal fold pathology. Material and Method: A descriptive study was designed in patients with benign vocal fold pathology between 3 and 15 years of age in the Voice Unit of the Dr. Luis Calvo Mackenna Children's Hospital between October 2016 and February 2020. The evaluation was carried out through a laryngoscopic examination and pVHI questionnaire to assess the impact on quality of life. Results: Forty-nine patients were included, 35 boys (71.4%) and 14 girls (28.6%). The mean age was 9.27 years. On laryngoscopic examination, the most frequent finding was vocal fold nodules. The total mean score on the pVHI was 38.77: 11.67 on the functional subscale, 18.59 on the physical subscale, and 8.42 on the emotional subscale. In the evaluation of pVHI by gender, no significant differences were found. Conclusion: Benign vocal fold pathology in pediatric age causes a negative impact on voice-related quality of life. The pVHI questionnaire is a valuable instrument to assess this repercussion.

Adaptación cultural y validación del índice de discapacidad vocal pediátrico al español chileno

Resumen Introducción: La prevalencia de patología vocal en niños fluctúa entre el 6% y el 23%. El cuestionario Pediatric Voice Handicap Index (pVHI) se ha transformado en el instrumento más utilizado a nivel internacional para determinar el impacto de la disfonía en la calidad de vida de los niños. Objetivo: Realizar la traducción, adaptación cultural y validación del Pediatric Voice Handicap Index al español chileno. Material y Método: Estudio transversal que incluyó a 151 niños y niñas entre 3 y 15 años. Se siguieron los 5 pasos recomendados por Beaton. La versión original del pVHI en inglés fue traducida al español por dos traductoras. Posteriormente, la versión traducida y unificada fue revisada por una lingüista chilena quien realizó la adaptación cultural al idioma español chileno. El cuestionario se aplicó a dos grupos de estudio, un grupo de niños con disfonía (n = 51) y un grupo control de niños sin alteraciones de la voz (n = 100) para obtener la versión final. Resultados: Se encontraron diferencias significativas entre el grupo de niños con disfonía y el grupo control en la puntuación global del pVHI y las diferentes subescalas (p < 0,001). Se encontró una consistencia interna óptima con un excelente alfa de Cronbach (α = 0,93), con una alta fiabilidad test-retest (puntuación de correlación de Pearson = 0,95). Conclusión: La versión chilena del cuestionario pVHI presenta un alto grado de validez y confiabilidad. Recomendamos su uso e implementación como protocolo estándar en la evaluación y seguimiento de la voz pediátrica.

Abstract Introduction: The prevalence of vocal pathology in children fluctuates between 6% and 23%. The pediatric voice handicap index (pVHI) questionnaire has become the most widely used instrument to determine the impact of dysphonia on the quality of life of children. Aim: Perform the translation, cultural adaptation, and validation of the pediatric voice handicap index into Chilean Spanish. Material and Method: Cross-sectional study that included 151 boys and girls between 3 and 15 years old. The 5 steps recommended by Beaton were followed. The original version of the pVHI in English was translated into Spanish by two translators. Subsequently, the translated and unified version was reviewed by a Chilean linguist who made the cultural adaptation to the Chilean Spanish language. The questionnaire was applied to two study groups, a group of children with dysphonia (n = 51) and a control group of children without voice disorders (n = 100) to obtain the final version. Results: Significant differences were found between the group of children with dysphonia and the control group in the global pVHI score and the different subscales (p < 0.001). Optimal internal consistency was found with excellent Cronbach's alpha (α = 0.93), with high test-retest reliability (Pearson's correlation score = 0.95). Conclusion: The Chilean version of the pVHI questionnaire presents a high degree of validity and reliability. We recommend its use and implementation as a standard protocol in the evaluation and monitoring of pediatric voice.

Atmospheric pressure X-ray photoelectron spectroscopy apparatus: Bridging the pressure gap.

One of the main goals in catalysis is the characterization of solid/gas interfaces in a reaction environment. The electronic structure and chemical composition of surfaces become heavily influenced by the surrounding environment. However, the lack of surface sensitive techniques that are able to monitor these modifications under high pressure conditions hinders the understanding of such processes. This limitation is known throughout the community as the "pressure gap." We have developed a novel experimental setup that provides chemical information on a molecular level under atmospheric pressure and in presence of reactive gases and at elevated temperatures. This approach is based on separating the vacuum environment from the high-pressure environment by a silicon nitride grid-that contains an array of micrometer-sized holes-coated with a bilayer of graphene. Using this configuration, we have investigated the local electronic structure of catalysts by means of photoelectron spectroscopy and in presence of gases at 1 atm. The reaction products were monitored online by mass spectrometry and gas chromatography. The successful operation of this setup was demonstrated with three different examples: the oxidation/reduction reaction of iridium (noble metal) and copper (transition metal) nanoparticles and with the hydrogenation of propyne on Pd black catalyst (powder).

Differentiation "in vitro" of primary and immortalized porcine mesenchymal stem cells into cardiomyocytes for cell transplantation.

Cell transplantation to regenerate injured tissues is a promising new treatment for patients suffering several diseases. Bone marrow contains a population of progenitor cells known as mesenchymal stem cells (MSCs), which have the capability to colonize different tissues, replicate, and differentiate into multilineage cells. Our goal was the isolation, characterization, and immortalization of porcine MSCs (pMSCs) to study their potential differentiation "in vitro" into cardiomyocytes. pMSCs were obtained from the aspirated bone marrow of Large-White pigs. After 4 weeks in culture, adherent cells were phenotypically characterized by flow cytometry and immunochemistry by using monoclonal antibodies. Primary pMSCs were transfected with the plasmid pRNS-1 to obtain continuous growing cloned cell lines. Fresh pMSCs and immortalized cells were treated with 5-azacytidine to differentiate them into cardiomyocytes. Flow cytometry analysis of isolated pMSCs demonstrated the following phenotype, CD90(pos), CD29(pos), CD44(pos), SLA-I(pos), CD106(pos), CD46(pos) and CD45(neg), CD14(neg), CD31(neg), and CD11b(neg), similar to that described for human MSC. We derived several stable immortalized MSC cell lines. One of these, called pBMC-2, was chosen for further characterization. After "in vitro" stimulation of both primary or immortalized cells with 5-azacytidine, we obtained different percentages (30%-50%) of cells with cardiomyocyte characteristics, namely, positive for alpha-Actin and T-Troponin. Thus, primary or immortalized pMSCs derived from bone marrow and cultured were able to differentiate "ex vivo" into cardiac-like muscle cells. These elements may be potentials tools to improve cardiac function in a swine myocardial infarct model.

The serum level of xenoantibodies, and hDAF or alphaGAL expression on pig cells, modulate in vitro the protection given by hDAF to primate complement-mediated damage.

The ability of human complement regulatory molecules to prevent xenograft rejection following pig-to-primate xenotransplantation is limited. We assayed the efficacy of transgenic human decay accelerating factor (hDAF) expressed on porcine cells to inhibit the in vitro complement activity of primate sera. We measured the cytotoxic activity of baboon or human sera against peripheral blood lymphocytes (PBLs) from hDAF or nontransgenic pigs using a flow cytometry complement-mediated cytotoxicity assay (FCCA). We also analyzed the anti-Galalpha1-3Gal (alphaGal) antibody titer of the baboon sera by ELISA and the expression of hDAF and alphaGal on the PBL surface by immunofluorescence. Transgenic hDAF expression was capable of protecting pig cells against injury produced by both baboon and human serum. However, the hDAF molecule was more efficient against human than baboon sera. The humoral cytotoxicity capacity correlated with the level of both IgG and IgM anti-alphaGal antibodies. In addition, inhibition of complement-mediated cytotoxicity of hDAF pig cells correlated with the expression of hDAF and alphaGal molecules on target cells. These results confirm in vitro the protective role of hDAF in pig cells to heterologus complement mediated damage, but they also suggest that protection decreases in the presence of high levels of anti-porcine antibodies in serum, low expression of hDAF, or high expression of alphaGal on pig cells.

[Descending necrotizing mediastinitis: treatment by transcervical thoracic drainage]. / Mediastinitis necrosante descendente: tratamiento con drenaje torácico transcervical.

We report the case of a 29-year-old man with descending necrotizing mediastinitis and subcarinal spread secondary to oropharyngeal infection. The thoracic infection was treated by placement of a transcervical thoracic drain, which was removed 15 days after surgery. The outcome was satisfactory and no further invasive treatment was required. We believe that transcervical thoracic drainage is a useful initial treatment for descending necrotizing mediastinitis with subcarinal spread but no pleural cavity involvement.

Flow cytometry complement-mediated cytotoxicity assay detects baboon xenoantibodies directed to porcine epitopes undetected by hemolytic assay.

The pig-to-primate model is increasingly being utilized as the final preclinical means of assessing therapeutic strategies aimed at allowing discordant xenotransplantation. To obtain information about the nature of cytotoxic response in pig-to-baboon xenotransplants, we sought to determine if serum cytotoxicity in this model was assay dependent. Sera from nine kidney or heart xenotransplanted baboons were obtained before transplantation and at the time of acute humoral xenograft rejection (AHXR). Cytotoxicity was measured by an anti-pig haemolytic assay (APHA) and by a flow cytometry complement-dependent assay (FCCA), using pig blood lymphocytes (PBLs). Serum samples showing inter-assay differences were absorbed with pig erythrocytes and assayed by APHA and FCCA, as well as by measuring anti-alphaGal and total anti-pig xenoantibodies. The results showed that in four AHXR samples, FCCA cytotoxicity was higher than APHA cytotoxicity. Absorption with pig erythrocytes diminished FCCA and removed APHA cytotoxicity. Residual FCCA activity was due to total anti-pig and IgM anti-alphaGal and non-Gal antibodies. Our results indicate that some cytotoxic antibodies present in the sera of xenotransplanted baboons at time of AHXR are IgM antibodies directed against pig PBL antigens not detected by APHA.

Response of cutaneous leishmaniasis (chiclero's ulcer) to treatment with meglumine antimoniate in Southeast Mexico.

Cutaneous leishmaniasis, known as chiclero's ulcer in southeastern Mexico, is characterized by a predominantly single, painless, ulcerated lesion, without lymphangitis or adenopathy. When located on the ear, it tends to become chronic, causing destruction of the pinna and disfigurement. It is caused predominantly by Leishmania (L.) mexicana. Although pentavalent antimonials (Sb5+) are the mainstay of leishmanial therapy and have been used for more than 50 years, dosage regimens have been repeatedly modified and the best one has not been fully identified. The main purpose of the present study was to investigate the response of chiclero's ulcer to treatment with meglumine antimoniate. One hundred five patients were treated with meglumine antimoniate at a daily dose of 1 ampule per day (425 mg of Sb5+) until healing. The lesions healed after a mean of 25 days (range = 5-60 days).

Renal cell carcinoma metastatic to the gallbladder or prostate: two case reports.

Although metastatic renal cell carcinoma (RCC) is not uncommon, dissemination to the gallbladder or prostate is very rare. We present 1 case of RCC with synchronous metastasis to the gallbladder and 1 case of RCC with metachronous metastasis to the prostate. These cases illustrate the propensity of RCC for unpredictable presentation and unusual sites of metastases. The first case also illustrates the benefit of adjuvant nephrectomy with excision of a solitary metastasis. Patterns of RCC metastases and flow cytometric analysis of RCC are discussed.