Impact of a SBRT/SRS longitudinal telehealth training pilot course in Latin America.

PURPOSE: To assess the impact of longitudinal telehealth training in stereotactic body radiation therapy (SBRT) and stereotactic radiosurgery (SRS) for clinicians in Latin America. MATERIALS AND METHODS: Professionals from two Peruvian centers received an initial SBRT/SRS on-site training course and subsequently received follow-up telehealth training (interventional group) or not (negative control arm). Twelve live video conference sessions were scheduled. Surveys pre- and post-curriculum measured participants' confidence in seven practical domains of SBRT/SRS, based on Likert scales of 1-5, and post-curriculum surveys assessed educators' experiences. RESULTS: Sixty-one participants were registered, with an average of 24 attendees per session. Pre- and post- surveys were completed by 22 participants. For interventional and negative-control groups, mean changes in Likert scale were satisfactory for the former and remained unmodified for the latter. CONCLUSIONS: Conducting telehealth educational programs via virtual classroom sessions could be a reliable method to augment training for SBRT and SRS.

Low-dose radiotherapy for COVID-19 pneumonia treatment: case report, procedure, and literature review.

BACKGROUND: The COVID-19 pandemic outbreak has set the emergency services in developing countries on major alert, as the installed response capacities are easily overwhelmed by the constantly increasing high demand. The deficit of intensive care unit beds and ventilators in countries like Peru is forcing practitioners to seek preventive or early interventional strategies to prevent saturating these chronically neglected facilities. CASE PRESENTATION: A 64-year-old patient is reported after presenting with COVID-19 pneumonia and rapidly progressing to deteriorated ventilatory function. Compassionate treatment with a single 1­Gy dose to the bilateral whole-lung volume was administered, with gradual daily improvement of ventilatory function and decrease in serum inflammatory markers and oxygen support needs, including intubation. No treatment-related toxicity developed. Procedures of transport, disinfection, and treatment planning and delivery are described. CONCLUSION: Whole-lung low-dose radiotherapy seems to be a promising approach for avoiding or delaying invasive respiratory support. Delivered low doses are far from meeting toxicity ranges. On-going prospective trials will elucidate the effectiveness of this approach.

Standard versus extended criteria graft procurement. Experience at the Hospital de Especialidades La Raza. / Procuración de injertos estándar frente a extendidos. Experiencia en el Hospital de Especialidades La Raza.

BACKGROUND: In Mexico, there are 23 158 patients waiting for an organ or tissue transplant. The increasing demand of grafts justifies the use of expanded criteria donors; however, not even all standard grafts have been procured. OBJECTIVE: To identify the associated factors to the decision of not procuring grafts from brain death donors whose donation was consented. METHOD: Retrospective cohort, univariate and multivariate analysis. 35 donation files with brain death were included from 2014 to 2019. Groups in which the heart wasn't procured versus those in which it was procured were compared; same comparisons were made for liver, kidney, skin, bone tissue and corneas. RESULTS: 20 women (57.1%), 15 men (42.9%) average age of 43.8 ± 16.4 years. High-dose of inotropic or norepinephrine use increased the probability of cardiac procurement (odds ratio [OR] 0.57; 95% confidence interval [95% CI]: 0.0-0.5). It was not detected a sensitive and specific variable for decision making at liver procurement. Implementation of two or more diagnostic methods for BD were associated with kidney loss (OR: 10; 95% CI: 1.2-78.1). Organs and tissues met standard criteria; however, 76 (41.5%) were not procured. CONCLUSIONS: Non-procurement associated factors were different from the standard donor established criteria. It is necessary to follow clear procurement criteria, in order to reduce viable grafts loss.

INTRODUCCIÓN: En México se registraron 23,158 personas en espera de un órgano o tejido para trasplante durante el año 2019. El constante aumento de la demanda sustenta el empleo de donantes con criterios extendidos; sin embargo, no todos los injertos estándar se procuran. OBJETIVO: Identificar los factores asociados a la decisión de no procurar injertos provenientes de donantes con muerte encefálica en quienes se consintió la donación. MÉTODO: Cohorte retrospectiva, análisis univariado y multivariado. Se incluyeron 35 expedientes de donación concretada con muerte encefálica de 2014 a 2019. Se compararon los grupos en los que no se procuró corazón, en los que sí, y para hígado, riñón, tejido óseo, piel y córneas. RESULTADOS: Se incluyeron 20 mujeres (57.1%) y 15 hombres (42.9%) con una edad media de 43.8 ± 16.4 años. El uso de inotrópico a dosis altas o norepinefrina aumentó la probabilidad de procuración cardiaca (razón de momios [RM]: 0.57; intervalo de confianza del 95% [IC95%]: 0.0-0.5). No se detectó ninguna variable sensible y específica para la toma de decisión en la procuración hepática. El empleo de dos o más métodos diagnósticos de muerte encefálica se asoció a pérdida del riñón (RM: 10; IC95%: 1.2-78.1). Cumplieron con criterios estándar 183 órganos y tejidos (74.6%); sin embargo, 76 (41.5%) no fueron procurados. CONCLUSIONES: Los factores asociados a la decisión de no procuración fueron distintos a los criterios de donante estándar establecidos. Es necesario seguir criterios claros de procuración para disminuir la pérdida de injertos viables.

Do Factors from Admissions and Dental School Predict Performance on National Board Exams? A Multilevel Modeling Study.

The aim of this study was to assess the association among admissions variables, dental school performance, and licensing exam performance for six cohorts of graduates of one dental school. Data from all dental school graduates of Schulich School of Medicine & Dentistry, Western University, Canada, from 2009 to 2014 who had matching National Dental Examining Board of Canada (NDEB) data (N=298) were analyzed. In the results, significant differences between cohorts were found on both the NDEB objective structured clinical examination (OSCE) and written scores. Approximately 18% of the variation in OSCE scores was attributable to cohort differences and 82% to student differences. Approximately 10% of the variation in written scores was attributable to cohort differences and 90% to student differences. Several multilevel models were conducted. The final predictive model for NDEB OSCE scores consisted of age, Canadian Dental Aptitude Test (DAT) reading comprehension scores, year 2 average, and year 4 average. For predicting NDEB written exam scores, the final model consisted of DAT chemistry and year 1, 2, and 4 averages. The findings of this study showed that academic performance on admissions variables and in training predicted performance on dental licensing exams, whereas variables that captured noncognitive or interpersonal skills, such as interview scores, were not predictive. This difference may be due to construct mismatch, such that the outcome variables had no theoretical association with the predictors. Additional outcome measures (including noncognitive) are needed that have greater ecological validity in predicting potential for competence in practice.

[Brain death: attitude and knowledge of medical personnel in a third level hospital]. / Muerte encefálica: actitud y conocimientos del personal médico en un hospital de especialidades.

BACKGROUND: Brain death is defined as the irreversible loss of all functions of the brain, including the brainstem. The objective is to know the attitude and knowledge toward brain death of the medical personnel involved in the process of the organ/tissue transplantation and donation in a third level hospital of Mexico City. METHODS: 67 attending physicians were interviewed with the methodology of pen, paper and a printed questionnaire. They were distributed in two groups: group A, consisting of non-surgical physicians, and group B, which was formed by surgical physicians. It was analyzed the attitude and knowledge of the criteria established in the Ley General de Salud (General Law of Health) of Mexico. Thirty-five men and 32 women (median age 42 years) responded to the survey. RESULTS: More than 90 % of both groups would wish to participate in a brain death course, and they would accept to be potential donors or receptors of transplanted organs. A high percentage knows partially the law on brain death (Ley General de Salud) and clinical procedures. Of the interviewed population, 68 % does not know the standard complementary studies to confirm the diagnosis of brain death. Non-significant differences were observed in the attitude and knowledge of both groups (p = 0.170). CONCLUSION: Physicians must improve their knowledge on brain death.

Introducción: la muerte encefálica se define como el cese irreversible de las funciones de las estructuras neurológicas intracraneales, tanto de los hemisferios cerebrales como del troncoencéfalo. El objetivo es conocer la actitud y los conocimientos que tiene ante la muerte encefálica el personal médico relacionado con el trasplante y la donación de órganos y tejidos en un hospital de tercer nivel de la ciudad de México. Métodos: fueron encuestados 67 médicos con el método de pluma, papel y un cuestionario impreso; se distribuyeron en dos grupos: grupo A no quirúrgicos y grupo B quirúrgicos. Se exploraron la actitud y los conocimientos de los criterios establecidos en la Ley General de Salud en México. Contestaron la encuesta 35 hombres y 32 mujeres, con una mediana de edad de 42 años. Resultados: más del 90 % en ambos grupos desearía participar en un curso-taller de muerte encefálica, así como ser potenciales donadores y receptores de órganos. Un alto porcentaje conoce parcialmente la ley sobre muerte encefálica y los conceptos clínicos. El 68 % de la población encuestada no conoce los estudios complementarios establecidos para confirmar el diagnóstico de muerte encefálica. Al comparar ambos grupos no se encontró diferencia significativa (p = 0.170). Conclusión: el médico debe responsabilizarse más en el dominio de la muerte encefálica.

[Modified cesarean-hysterectomy technique for management of placenta accreta]. / Técnica cesárea-histerectomía modificada para el tratamiento del acretismo placentario.

UNLABELLED: BAKGROUND: Obstetric hemorrhage is a major cause of maternal morbidity. The increasing number of births via cesarean has increased the incidence of placenta accreta worldwide. As new techniques aimed at reducing maternal mortality and morbidity have emerged with varying results. OBJECTIVES: To describe the surgical technique used in our hospital for management of placenta accreta. Report outcomes and maternal complications. METHODS: Descriptive study, data were obtained from clinical records of patients diagnosed with placenta accreta and whose management was by our modified technique cesarean-hysterectomy by a multidisciplinary team. We included patients who were treated at the Hospital Civil de Guadalajara Dr. Juan I. Menchaca in the period from April 1, 2008 to November 1, 2012. RESULTS: 23 patients were included. The mean gestational age at Doppler ultrasound diagnosis was 31 +/- 3 weeks and for termination of pregnancy was 34 +/- 1 weeks of gestation. Only 5 patients were admitted to intensive care, one patient suffer bladder injury noticed and repaired. CONCLUSIONS: Our modified technique cesarean-hysterectomy for management of placenta accreta has reduced mortality and morbidity in our hospital as well as injuries to nearby organs and hospital stay.

Guidelines from the Canadian Association of Pathologists for establishing a telepathology service for anatomic pathology using whole-slide imaging.

The use of telepathology for clinical applications in Canada has steadily become more attractive over the last 10 years, driven largely by its potential to provide rapid pathology consulting services throughout the country regardless of the location of a particular institution. Based on this trend, the president of the Canadian Association of Pathologists asked a working group consisting of pathologists, technologists, and healthcare administrators from across Canada to oversee the development of guidelines to provide Canadian pathologists with basic information on how to implement and use this technology. The guidelines were systematically developed, based on available medical literature and the clinical experience of early adopters of telepathology in Canada. While there are many different modalities and applications of telepathology, this document focuses specifically on whole-slide imaging as applied to intraoperative pathology consultation (frozen section), primary diagnosis, expert or second opinions and quality assurance activities. Applications such as hematopathology, microbiology, tumour boards, education, research and technical and/or standard-related issues are not covered.

Memory T Cells Mediate Cardiac Allograft Vasculopathy and are Inactivated by Anti-OX40L Monoclonal Antibody.

PURPOSE: Cardiac allograft vasculopathy (CAV) is a major complication limiting the long-term survival of cardiac transplants. The role of memory T cells (Tmem) in the pathogenesis of CAV remains elusive. This study investigated the role of Tmem cells in the development of CAV and the therapeutic potential of targeting the OX40/OX40L pathway for heart transplant survival. METHODS: Tmem cells were generated in Rag-1(-/-) C57BL/6 (B6) mice by homeostatic proliferation (HP) of CD40L null CD3(+) T cells from B6 mice. Rag-1(-/-) B6 mice (H-2(b)) harboring Tmem cells received cardiac allografts from BALB/c mice (H-2(d)), and were either untreated or treated with anti-OX40L monoclonal antibody (mAb) (0.5 mg/mouse/day) for 10 days. RESULTS: Six weeks after HP, the majority of transferred CD40L(-/-) T cells in Rag-1(-/-) B6 mice were differentiated to CD44(high) and CD62L(low) Tmem cells. BALB/c heart allografts in Rag-1(-/-) B6 recipient mice in the presence of these Tmem cells developed a typical pathological feature of CAV; intimal thickening, 100 days after transplantation. However, functionally blocking the OX40/OX40L pathway with anti-OX40L mAb significantly prevented CAV development and reduced the Tmem cell population in recipient mice. Anti-OX40L mAb therapy also significantly decreased cellular infiltration and cytokine (IFN-γ, TNF-α and TGF-ß) expression in heart allografts. CONCLUSIONS: Tmem cells mediate CAV in heart transplants. Functionally blocking the OX40/OX40L pathway using anti-OX40L mAb therapy prevents Tmem cell-mediated CAV, suggesting therapeutic potential for disrupting OX40-OX40L signaling in order to prevent CAV in heart transplant patients.

Carbon monoxide releasing molecules inhibit cell death resulting from renal transplantation related stress.

PURPOSE: Organ cold storage and subsequent transplantation are associated with significant ischemia-reperfusion injury, leading to cell death, graft inflammation and decreased graft function. MATERIALS AND METHODS: CORM-3s reduce oxidative stress and prevent inflammation in kidneys stored at 4C and subsequently transplanted. Graft survival and function are markedly improved compared to kidneys preserved and stored in University of Wisconsin solution alone. We determined whether CORM-3 has direct antiapoptotic effects on in vitro preparations of human HUVECs exposed to anoxic conditions. We also determined whether direct administration of CORM-3 to renal grafts before and/or after cold storage would prevent renal damage during the transplantation process. RESULTS: CORM-3 supplementation led to a significantly increased frequency of live cells (mean ± SD 72.3% ± 1.9%, p <0.01), reduced apoptosis (14.9% ± 6.1%, p <0.01) and decreased mitochondrial transmembrane potential (40.2% ± 7.2%, p <0.05) in HUVECs exposed to 20 hours of cold storage compared to controls (11.6% ± 3.5%, 82.2% ± 2.3% and 78.2% ± 3.2%, respectively). In keeping with this antiapoptotic effect CORM-3 supplementation led to a mean 7.4 ± 2.1-fold up-regulation in Bcl-2 gene expression. CORM-3 supplementation in standard preservation solution was most beneficial at initial ischemic injury and before cold storage exposure. However, additional reflushing before vascular reperfusion showed an additive benefit to graft survival and function after transplantation. This was confirmed by decreased glomerular and tubular necrosis, and apoptosis in double flushed grafts. CONCLUSIONS: CORM-3 supplementation in standard University of Wisconsin solution has a significant impact on decreasing cellular and graft injury, and improving survival through its antiapoptotic effects, which are likely mediated through mitochondrial membrane stabilization.

Supplemental hydrogen sulphide protects transplant kidney function and prolongs recipient survival after prolonged cold ischaemia-reperfusion injury by mitigating renal graft apoptosis and inflammation.

UNLABELLED: What's known on the subject? and What does the study add? Hydrogen sulphide (H(2) S) has recently been classified as a member of the family of small gaseous molecules called gasotransmitters and has been found to have many important physiological functions. Several recent studies have elucidated the protective effects of H(2) S in many models of tissue ischaemia-reperfusion injury (IRI), including hepatic, myocardial, pulmonary, cerebral and renal IRI. It has previously been shown that H(2) S has a number of properties that may contribute to its protection against IRI, including vasodilatory, anti-apoptotic, anti-inflammatory and anti-oxidant effects, although the specific actions appear to vary between tissues. The few studies investigating the effects of H(2) S against renal IRI have only involved clamping of the renal pedicle to induce warm IRI. This study investigated the protective effects of H(2) S in the context of renal transplantation (RTx), which generally involves a more severe period of prolonged cold IRI. A previous study investigated the actions of H(2) S in RTx, but it was performed ex vivo and did not involve actual transplantation of donor kidneys. To our knowledge, this is the first study using a clinically relevant model of RTx to show that treatment of donor kidneys with H(2) S during preservation is protective against prolonged cold IRI. These findings suggest that H(2) S has potential utility in improving clinical organ preservation techniques and increasing the overall success of organ transplantation. OBJECTIVE: • To characterize the effects of hydrogen sulphide (H(2) S), an endogenously produced molecule recently described to have protective effects against warm ischaemic tissue injury, in mitigating transplantation-associated prolonged cold ischaemia-reperfusion injury (IRI) in a clinically applicable in vivo model of renal transplantation (RTx). MATERIALS AND METHODS: • After undergoing bilateral native nephrectomy, Lewis rats underwent RTx with kidneys that were flushed with either cold (4 °C) standard University of Wisconsin preservation solution (UW) or cold UW + 150 µM NaHS (H(2) S) solution and stored for 24 h at 4 °C in the same solution. • Recipient rats were monitored for a 14-day time course using metabolic cages to assess various characteristics of renal graft function. • Renal grafts were removed at time of death or after the rats were killed for histological, immunohistochemical and quantitative PCR analysis. RESULTS: • H(2) S-treated rats exhibited immediate and significant (P < 0.05) decreases in serum creatinine levels, increased urine output and increased survival compared with UW-treated rats. • H(2) S-treated grafts showed significantly reduced glomerular and tubular necrosis and apoptosis, diminished graft neutrophil and macrophage infiltrates and a trend towards improved inflammatory and anti-apoptotic cytokine profiles. CONCLUSION: • Our results provide the first evidence that supplemental H(2) S can mitigate renal graft IRI incurred during transplantation and prolonged cold storage, improving early graft function and recipient survival in a clinically applicable model of RTx.

Costimulation blockade in pig artery patch xenotransplantation - a simple model to monitor the adaptive immune response in nonhuman primates.

BACKGROUND: CD154 blockade-based immunosuppression successfully prevents both humoral and cellular adaptive immune responses in baboons receiving α1,3-galactosyltransferase gene-knockout (GTKO) pig organs. Using a GTKO pig artery transplantation model in baboons, we evaluated the efficacy of CD28/B7 costimulatory pathway blockade in comparison with CD154 blockade. METHODS: Baboons received artery patch grafts from GTKO pigs, with no (Group1), anti-CD154mAb-based (Group2), or CTLA4-Ig-based (Group3) immunosuppressive therapy. Anti-pig IgM and IgG antibody and cellular responses were monitored. Xenografts were immunohistologically evaluated for antibody and complement deposition, and cellular infiltration. RESULTS: Group1 baboons developed increased IgM and IgG antibody and cellular responses against GTKO antigens. In Group2, anti-CD154mAb alone prevented the development of both IgM and IgG antibody and cellular responses,but not cellular infiltration of the graft. In the single baboon that received anti-thymocyte globulin (ATG) + mycophenolate mofetil (MMF) + anti-CD154mAb, cellular infiltration of the graft was not seen. In Group3, CTLA4-Ig with ATG + MMF inhibited the cellular proliferative response to pig antigens but did not prevent the IgG response or cellular infiltration. CONCLUSIONS: (i) Artery patch transplantation is a simple model to monitor the adaptive immune response to xenografts; (ii) anti-CD154mAb prevents sensitization but not cellular infiltration (but, without anticoagulation, may result in early thrombosis of a pig xenograft); (iii) although in only one baboon, the addition of ATG and MMF prevents cellular infiltration and (iv) replacement of anti-CD154mAb by CTLA4-Ig (at the doses used), even in combination with ATG and MMF, prevents the cellular proliferative response to GTKO pig antigens but is insufficient to prevent the development of anti-pig antibodies.

Effect of an angiogenesis inhibitor on hepatic tumor perfusion and the implications for adjuvant cytotoxic therapy.

PURPOSE: To determine whether dynamic contrast material-enhanced (DCE) computed tomography (CT) can help identify hepatic tumor perfusion response to vascular remodeling induced by antiangiogenesis treatment in a rabbit model. MATERIALS AND METHODS: The study was approved by the Animal Use Subcommittee of the University Council on Animal Care. DCE CT hepatic perfusion measurements were performed in the livers of 20 rabbits implanted with VX2 carcinoma. Vascular remodeling was induced with thalidomide dissolved in dimethyl sulfoxide and sterile water, starting at a tumor diameter of 0.7 cm±0.1 and continuing until metastatic lung nodules were observed. The control group (n=8) was given an equivalent volume of the vehicle. The therapy group was subdivided into animals that survived for more than 24 days without lung metastasis (responder group, n=5) or those that survived for less than 24 days (nonresponder group, n=7). Data were analyzed with the Kruskal-Wallis or Friedman rank test and reported as medians and interquartile ranges. RESULTS: DCE CT depicted differential perfusion change within the therapy group after treatment. By day 4, hepatic blood volume (HBV) in the responder group decreased by 29.2% (-32.5% to -11.8%) relative to that before treatment and was significantly different from that in the nonresponder (P=.048) and control (P=.011) groups, where HBV remained stable. By day 8, hepatic artery blood flow decreased by 50.0% (-59.08% to -21.05%) relative to that before treatment in the responder group and was significantly different from that in the nonresponder and control groups (P=.030 for both), which remained stable at -3.5% (-8.5% to 28.7%, P=.50) and -10.0% (-33.8% to 10.4%, P=.48), respectively. CONCLUSION: DCE CT can help differentiate responders from nonresponders by their early differential perfusion response to antiangiogenesis therapy.

Familial papillary thyroid carcinoma: a retrospective analysis.

Background. Whether or not the familial form of papillary thyroid carcinoma is more aggressive than the sporadic form of the disease remains controversial. Methods. To explore this question and whether or not increased aggressiveness is more apparent in families with multiple affected members, we performed a chi square by trend analysis on our patients clinical and pathologic data comparing: first degree families with three or more affected members versus first degree families with two affected members versus sporadic cases of papillary thyroid carcinoma. Results. No statistically significant trends were seen for any presenting surgical pathology parameter, age at presentation, length of follow-up or gender distribution. The familial groups exhibited significant trends for higher rates of reoperation (P = 0.05) and/or requiring additional radioactive iodine therapy (P = 0.03), distant metastases (P = 0.003) and deaths (P = 0.01). These aggressive features were most apparent in certain families with three or more affected members. Conclusions. Using the chi square by trend analysis, a significant trend was seen for the familial form of papillary thyroid cancer to possess more aggressive features than the sporadic disease. Prompt recognition of the familial nature of the disease may provide earlier diagnosis and treatment in similarly affected family members.

Diseño y construcción de un espirómetro pitot computarizado para tratamientos con radioterapia de tumores que se mueven durante la respiración / Design and construction of a computerized spirometer pitot radiotherapy treatments for tumors that move during breathing

Introducción: Ciertos tumores se mueven junto con los movimientos respiratorios dificultando la del tratamiento con la radioterapia. El propósito de este estudio fue implementar una técnica adaptada a la respiración para minimizar el movimiento del tumor, utilizando tecnología desarrollada en nuestro medio. Métodos: Con la ayuda de sensores de caudal de aire que provienen de la respiración, se generaron señales que fueron transformadas en gráficos por medio de interfaces mediante un software diseñado por los investigadores. El procedimiento de utilización de esta técnica constó de tres fases (calibración, entrenamiento y tratamiento). Para demostrar la eficacia de la técnica, se requirió tomar varias series TAC de simulación de diferentes momentos y al mismo paciente para demostrar que el isocentro del tumor no variaba cuando la respiración era bloqueada en el mismo momento del ciclo respiratorio. Resultados: El trabajo de diseño y construcción del espirómetro pitot computarizado se prolongó por cerca de un año, posteriormente se realizaron las pruebas en el equipo de tomografía y un planificador CAT PLAN. La técnica fue fácilmente aprendida por los pacientes. El isocentro del tumor en las diferentes series no sufrió cambios mayores a los 2 mm, con una desviación aceptada y atribuida a la incertidumbre por contorno. El GTV fue mucho mayor en la respiración libre que en respiración bloqueada hasta el 32%. El PTV presentó cambios más drásticos (mayor en 62%). Se observó que cuando se bloquea la respiración en inspiración profunda, el volumen pulmonar aumenta hasta en un 30%, disminuyendo de esta manera el volumen de pulmón sao irradiado. Conclusión: la viabilidad de un diseño de espirómetros de este tipo amplía las posibilidades para el mejoramiento técnico de mayor envergadura, como la miniaturización del equipo, la comunicación inalámbrica de datos y la aplicación de otros sistemas médicos de imágenes como angiofluoroscopía y aplicación...

Introduction: Some tumors move along with the respiratory movements making it hard the treatment with radiotherapy. The aim of this study was to set up a technique adapted with respiration in order to minimize the tumor’s movement with respiration by using our own developed technology. Methods: With help o sensors of air volume which come from breathing, was generated signals that were transformed in graphics through interfaces by software, designed by our researchers. The method of utilization of this technique is listed of three stages (calibration, training and treatment). In order to show the efficacy of this technique, it was required to take several series of TAC of simulation, on different times and to the same patient, with the aim to show the tumor’s isocenter does not vary when the respiration was blocked at the same moment of the respiratory cycle. Results: The work design and construction of the computer pitot spirometer was prolonged near to a year. After that, tests were performed by the tomography equipment and the planner CAT PLAN. This technique was easily learned by patients. The tumor’s isocenter on the different series did not suffer mayor changes to 2 mm, with accepted deviation and attribute it to the uncertainty for contour. The GTV was much major in free respiration than blocked on 32%. The PTV presented more drastic changes (major on 62). We observed that when respiration in blocked on deep inspiration, the pulmonary volume grows about 30%, decreasing for this way the volume of the irradiated healthy lung. Conclusion: The viability of a design of espirometers of this type extend the possibilities to technical improvement of major magnitude, such as the miniaturization of the equipment, the wireless communication of data and the application in the other medical imaging systems as angiofluoroscopia the application to equipment of old generation without incorporated systems.

Carbon monoxide-releasing molecules protect against ischemia-reperfusion injury during kidney transplantation.

Carbon monoxide (CO) can provide beneficial antiapoptotic and anti-inflammatory effects in the context of ischemia-reperfusion injury (IRI). Here we tested the ability of pretreating the kidney donor with carbon monoxide-releasing molecules (CORM) to prevent IRI in a transplant model. Isogeneic Brown Norway donor rats were pretreated with CORM-2 18 h before kidney retrieval. The kidneys were then cold-preserved for 26 h and transplanted into Lewis rat recipients that had undergone bilateral nephrectomy. Allografts from Brown Norway to Lewis rats were also performed after 6 h of cold ischemic time with low-dose tacrolimus treatment. All recipients receiving CORM-2-treated isografts survived the transplant process and had near-normal serum creatinine levels, whereas all control animals died of uremia by the third post-operative day. This beneficial effect was also seen in isografted Lewis recipients receiving kidneys perfused with CORM-3, indicating that CORMs have direct effects on the kidney. Pretreatment of human umbilical vein endothelial cells in culture with CORM-2 for 1 h significantly reduced cytokine-induced nicotinamide adenine dinucleotide phosphate-dependent production of superoxide, activation of the inflammation-relevant transcription factor nuclear factor-κB, upregulated expression of E-selectin and intercellular adhesion molecule-1 adhesion proteins, and leukocyte adhesion to the endothelial cells. Thus, CORM-2-derived CO protects renal transplants from IRI by modulating inflammation.

Adoptive transfer of DNT cells induces long-term cardiac allograft survival and augments recipient CD4(+)Foxp3(+) Treg cell accumulation.

Regulatory T (Treg) cells play an important role in the regulation of immune responses but whether Treg will induce tolerance in transplant recipients in the clinic remains unknown. Our previous studies have shown that TCRαß(+)CD3(+)CD4⁻CD8⁻NK1.1⁻ (double negative, DN) T cells suppress T cell responses and prolong allograft survival in a single locus MHC-mismatched mouse model. In this study, we investigated the role of DNT cells in a more robust, fully MHC-mismatched BALB/c to C57BL/6 transplantation model, which may be more clinically relevant. Adoptive transfer of DNT cells in combination with short-term rapamycin treatment (days 1-9) induced long-term heart allograft survival (101±31 vs. 39±13 days rapamycin alone, p<0.01). Furthermore adoptive transfer DNT cells augmented CD4+Foxp3+ Treg cells accumulation in transplant recipients while depletion of CD4(+) Treg cells by anti-CD25 inhibited the effect of DNT cells on long-term graft survival (48±12 days vs. 101±31 days, p<0.001). In conclusion, DNT cells combined with short-term immunosuppression can prolong allograft survival, which may be through the accumulation of CD4(+)Foxp3(+) Treg cells in the recipient. Our result suggests that allograft tolerance may require the co-existence of different type Treg cell phenotypes which are affected by current immunosuppression.

Anti-IL-2 receptor antibody decreases cytokine-induced apoptosis of human renal tubular epithelial cells (TEC).

BACKGROUND: Transplant rejection is mediated by T-cell activation which is modulated by interleukin-2 (IL-2) binding to IL-2R (CD25). Monoclonal anti-IL-2 receptor antibody is used in renal transplantation to reduce rejection. Interestingly, proximal tubular epithelial cells (TEC) express CD25, similar to T cells. We have demonstrated that IL-2 induces murine TEC apoptosis through down-regulation of the caspase-8 inhibitor protein c-FLIP. Anti-CD25 antibody may be useful clinically to limit renal injury, but this has not been tested in human TEC. METHODS: Human PT-2 TEC were isolated and cloned from the urine of transplant patients. Apoptosis was determined by FACS with Annexin-V FITC. Protein expression was studied using western blot, and mRNA levels by quantitative real-time (PR-PCR). RESULTS: We demonstrated that the morphology of a human kidney cell line (PT-2) cloned from urine was consistent with proximal TEC and expresses alkaline phosphatase, cytokeratin, vimentin, CD13, CD26, and low levels of E-cadherin. Basal IL-2 receptor (CD25) was up-regulated by IL-2/IFN-γ stimulation, and cytokine exposure induced apoptosis in a dose-dependent manner. Apoptosis with IL-2/IFN-γ was associated with increased caspase-8 activity and decreased endogenous caspase-8 inhibitor c-FLIP mRNA and protein expression. IL-2/IFN-γ-induced apoptosis could be blocked by pre-treatment of PT-2 with anti IL-2R antibody (basiliximab) but not control IgG antibody. CONCLUSIONS: These data demonstrate for the first time in human TEC that IL-2 and IFN-γ can induce TEC apoptosis which can be blocked by CD25 blockade antibody. These data suggest that anti-CD25 mAb might similarly attenuate inflammation-induced TEC injury in vivo. Kidney-expressed CD25 may represent a clinically important new target for attenuating early inflammatory injury in donor kidneys and preserving renal function during anti-rejection therapy.

Prevention of chronic renal allograft rejection by soluble CD83.

BACKGROUND: Recombinant human soluble CD83 had previously exhibited significant immunosuppressive properties that involved interference with dendritic cell maturation in both mouse and humans, inhibition of autoimmunity in mice, and induction of antigen-specific mouse cardiac allograft tolerance when used in combination with other immunosuppressive drugs. Our current research focus turned to examining the effects of peritransplant soluble CD83 (sCD83) administration on prevention of chronic renal allograft rejection. METHODS: Fisher344-to-Lewis orthotopic rat renal transplants were performed with sequential recipient killing on postoperative days (PODs) 2, 14, and 140 to examine both the acute and chronic effects of peritransplant sCD83 treatment in rat recipients. RESULTS: Recipients treated with sCD83 exhibited a marked decrease in IgM and IgG deposition in the graft and antidonor antibody levels in the circulation, as early as POD14 and persisting until POD140. sCD83 treatment also reduced the infiltration of T cells and monocytes into the graft tissue and inhibited intragraft expression of MyD88 and inflammatory cytokine levels during the observation period. sCD83-treated grafts demonstrated normal histology beyond POD140, including dramatic reductions in tubular atrophy and interstitial fibrosis compared with untreated recipients. CONCLUSION: We have demonstrated that peritransplant treatment with recombinant sCD83 attenuates both innate and adaptive immune responses and leads to prevention of chronic rejection in a rat renal transplant model. Because sCD83 is of human origin, the therapeutic approach used in our rodent transplant model holds significant promise for clinical transplantation.

Regulatory T-cell generation and kidney allograft tolerance induced by mesenchymal stem cells associated with indoleamine 2,3-dioxygenase expression.

BACKGROUND: The immunoregulatory properties of mesenchymal stem cells (MSCs) have been observed in vitro and in vivo. However, the underlying mechanisms of this immunomodulation remain undefined. Recent research demonstrated that MSCs express the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO), known to suppress T-cell responses. This study was designed to address whether MSCs induce kidney allograft tolerance and whether IDO contributes to the immunoregulatory functions of MSCs in vivo. METHODS: MSCs (1×10(6), intravenously) from wild-type (WT-MSCs) or IDO knockout (IDO(-/-)-MSCs) C57BL/6 mice were injected into BALB/c recipients 24 hr after receiving a life-supporting orthotopic C57BL/6 renal graft. RESULTS: WT-MSC-treated recipients achieved allograft tolerance with normal histology and undetectable antidonor antibody levels. Tolerant recipients demonstrated increased circulating kynurenine levels and significantly high frequencies of tolerogenic dendritic cells. They also exhibited significantly impaired CD4+ T-cell responses consisting of decreased donor-specific proliferative ability and a Th2-dominant cytokine shift. In addition, high frequencies of CD4+CD25+Foxp3+ regulatory T cells (Tregs) were found in recipient spleens and donor grafts, with antibody-induced CD25+ cell depletion confirming the critical role of Tregs in the MSC-induced tolerance. Interestingly, renal allograft recipients treated with WT MSCs concomitant with the IDO inhibitor 1-methyl-tryptophan, or those treated with IDO(-/-)-MSCs alone, were unable to achieve allograft tolerance--revealing that functional IDO was necessary for the immunosuppression observed with WT-MSC treatment. CONCLUSIONS: IDO secreted by MSCs was responsible, at least in part, for induction of kidney allograft tolerance through generation of Tregs. This study supports the clinical application of MSCs in transplantation.