Leveling Up the Access to Radiation Therapy in Latin America: Economic Analysis of Investment, Equity, and Inclusion Opportunities Up to 2030.

PURPOSE: Latin America faces a shortage in radiation therapy (RT) units and qualified personnel for timely and high-quality treatment of patients with cancer. Investing in equitable and inclusive access to RT over the next decade would prevent thousands of deaths. Measuring the investment gap and payoff is necessary for stakeholder discussions and capacity planning efforts. METHODS AND MATERIALS: Data were collected from the International Atomic Energy Agency's Directory of Radiotherapy Centers, industry stakeholders, and individual surveys sent to national scientific societies. Nationwide data on available devices and personnel were compiled. The 10 most common cancers in 2020 with RT indication and their respective incidence rates were considered for gap calculations. The gross 2-year financial return on investment was calculated based on an average monthly salary across Latin America. A 10-year cost projection was calculated according to the estimated population dynamics for the period until 2030. RESULTS: Eleven countries were included in the study, accounting for 557,213,447 people in 2020 and 561 RT facilities. Approximately 1,065,684 new cancer cases were diagnosed, and a mean density of 768,469 (standard deviation ±392,778) people per available unit was found. By projecting the currently available treatment fractions to determine those required in 2030, it was found that 62.3% and 130.8% increases in external beam RT and brachytherapy units are needed from the baseline, respectively. An overall regional investment of approximately United States (US) $349,650,480 in 2020 would have covered the existing demand. An investment of US $872,889,949 will be necessary by 2030, with the expectation of a 2-year posttreatment gross return on investment of more than US $2.1 billion from patients treated in 2030 only. CONCLUSIONS: Investment in RT services is lagging in Latin America in terms of the population's needs. An accelerated outlay could save additional lives during the next decade, create a self-sustaining system, and reduce region-wide inequities in cancer care access. Cash flow analyses are warranted to tailor precise national-level intervention strategies.

Biochemical failure and toxicity in treatment with brachytherapy and external beam radiotherapy compared with radical prostatectomy in localized prostate cancer.

Background: Localized prostate cancer (T1-3N0M0) has therapeutic options such as radical prostatectomy (RP), external beam radiation therapy (EBRT) and brachytherapy (BT). However, the evidence of the outcome of these treatments is limited and no studies have been conducted comparing biochemical failure (BF) and toxicity associated with surgical treatment and EBRT + high-dose brachytherapy (HDBT) in the region. Materials and methods: Retrospective cohort study, clinical records of patients diagnosed with localized prostate cancer between 2014 and 2018 were reviewed at one of the main private neoplasm centers in Lima, Peru; Cox regression was used for both the BF outcome and the grade 2 toxicity outcome, calculating the hazard ratio (HR) with 95% confodence interval (CI). Results: Of 549 patients, 76.3% (419) received RP as primary treatment, and 72% were between 50 and 70 years old at the time of diagnosis. The patients treated with EBRT + HDBT presented worse characteristics. The EBRT + HDBT group had a 40% lower risk of presenting BF (HR = 0.6; 95% CI: 0.4-0.9), and also a 50% greater risk of presenting toxicity greater than or equal to grade 2 (HR = 1.5; 95% CI: 1.0-2.0) than the group treated with RP. Conclusion: Our results show that when comparing patients treated with EBRT + HDBT and RP, BF was greater in RP, and post-treatment toxicity was greater in EBRT + HDBT.

Long-Term Outcomes of an International Cooperative Study of Intraoperative Radiotherapy Upfront Boost With Low Energy X-Rays in Breast Cancer.

Purpose: The purpose of this study was to assess the effectivity of upfront kilovoltage intraoperative radiotherapy (IORT) as a boost in high-risk early-stage breast cancer patients from an international pooled cohort. Materials/Methods: Patients from four centers in three different countries were retrospectively screened. Those with a minimum 1-year follow-up were included. Cumulative local (LR), regional (RR), and distant metastasis rates (DM) were analyzed. Additionally, the estimated overall survival (OS) was assessed. The Cox regression analysis was performed to identify failure predicting factors. Results: A total of 653 patients from centers in Peru, Spain, and Germany were included. The median follow-up was 55 (12-180) months, and age was 58 (27-86) years. Clinical tumor (T) staging was T1 65.85%, T2 30.17%, and T3 3.98%. Positive margins were found in 7.9% and in-situ component in 20.06%. The median IORT dose was 20 (6-20). The median time from IORT to EBRT was 74.5 (13-364) days. An overall 3.4% (n = 22) of patients developed local recurrence at some point during follow-up. The 12-, 60-, and 120-month cumulative LR were 0.3%, 2.3%, and 7.9%, respectively. After multivariate analysis, only age <50 remained to be a significant prognostic factor for local recurrence (HR 0.19, 95% CI 0.08-0.47; p < 0.05). The 10-year estimated OS was 81.2%. Conclusion: Upfront boost with IORT yields similar local control outcomes to those EBRT-based reports. Results from prospective trials, regarding toxicity, cosmesis, and effectivity are awaited to confirm these findings.

Uso de adrenalina en el tratamiento de la hematuria persistente / Use of epinephrine in the treatment of persistent hematuria

La hematuria persistente es un signo habitual en los cuidados paliativos cuyo tratamiento sigue siendo un desafío. En este caso, la hematuria se presentó en una paciente de 78 años anticoagulada en el contexto de una fractura iliopúbica que se complicó con trombosis venosa profunda y tromboembolismo pulmonar. Para el tratamiento, se optó en un primer momento por lavados vesicales continuos con suero fisiológico. Dada la persistencia de la hematuria y la agudización de la anemia, se decidió añadir a los lavados con suero una ampolla de adrenalina. La paciente presentó buena tolerancia hemodinámica al tratamiento con adrenalina y mostró una mejoría clínica significativa, lo que permitió retirar la adrenalina y añadir a los lavados con suero ácido tranexámico (no realizado antes por el riesgo de obstrucción de la sonda por coágulos). Tras dos días con orina de aspecto claro se retiraron los lavados continuos. (AU)

Persistent hematuria is a common sign in palliative care whose treatment is still a challenge. In this case, hematuria occurred in a 78-year-old anticoagulated patient in the context of an iliopubic fracture complicated by deep vein thrombosis and pulmonary thromboembolism. For treatment, the first option was continuous bladder irrigation with saline solution. Given the persistence of hematuria and the worsening anemia, it was decided to add an ampoule of epinephrine to the bladder irrigation with saline solution. The patient presented good hemodynamic tolerance to adrenaline treatment and showed significant clinical improvement. This allowed withdrawal of epinephrine and addition of tranexamic acid to the serum (which was not done before because of the risk of catheter obstruction due to clots). After two days with clear urine, the continuous bladder irrigation were withdrawn. (AU)

Cometabolic biotransformation of benzotriazole in nitrifying batch cultures.

Benzotriazole (BT) is a corrosion inhibitor widely distributed in aquatic environments. Little is known about the cometabolic capacity of stabilized nitrifying sludge to biotransform BT. The contribution of the nitrification process in the simultaneous oxidation of ammonium and biotransformation of BT (5 mg/L) was evaluated in 49 d batch cultures inoculated with a sludge produced in steady-state nitrification. The nitrifying sludge could consume BT in the obligate presence of ammonium. A higher cometabolic biotransformation capacity was obtained by increasing the initial ammonium concentration (100-300 mg N/L), reaching 2.3- and 5.8-fold increases for efficiency and specific rate of BT removal. At 300 mg NH4+-N/L, the sludge biotransform 40.8% of BT and 77.6% of ammonium which was completely oxidized into nitrate. In assays with allylthiourea added as specific inhibitor of ammonium monooxygenase (AMO), it was shown that the totality of BT cometabolic biotransformation was associated with the AMO activity. The addition of acetate did not favor heterotrophic biotransformation of BT. BT provoked inhibitory effects on nitrification. This is the first study showing the role of ammonium oxidizing bacteria in the cometabolic biotransformation of BT and their potential use for cometabolism application in treatment of wastewater contaminated with ammonium and BT.

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.

Daño hepático inducido por dronedarona. Descripción de un caso clínico / Dronedarone-induced liver injury. A case report

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Leiomioma de la uretra, localización inusual del tumor pélvico femenino más frecuente / An unusual location of urethral leiomyoma, the most common pelvic tumour in the female

El leiomioma de la uretra es un raro tumor de origen mesenquimal que deriva del músculo liso de la uretra. Suele aparecer en mujeres en edad fértil. Actualmente se han publicado poco más de 100 casos de este tumor. La mayoría de las mujeres presentan síntomas como hematuria, infección urinaria y otros con relación al efecto masa del tumor. Presentamos el caso de una mujer de 42 años que debuta con hematuria esporádica, disuria y dispareunia, confirmándose en el estudio histológico la presencia de un leiomioma de la uretra (AU)

Urethral leiomyoma is a rare benign mesenchymal tumour arising from the smooth muscle of the urethra. It most often appears in females of reproductive age. Approximately 100 cases have been reported to date. The most usual presentation is urinary infection, hematuria or a mass. We report a case of a 42 year old woman who presented with sporadic hematuria, dysuria and dyspareunia. Histopathological studies confirmed urethral leiomyoma (AU)

[An unusual location of urethral leiomyoma, the most common pelvic tumour in the female]. / Leiomioma de la uretra, localización inusual del tumor pélvico femenino más frecuente.

Urethral leiomyoma is a rare benign mesenchymal tumour arising from the smooth muscle of the urethra. It most often appears in females of reproductive age. Approximately 100 cases have been reported to date. The most usual presentation is urinary infection, hematuria or a mass. We report a case of a 42 year old woman who presented with sporadic hematuria, dysuria and dyspareunia. Histopathological studies confirmed urethral leiomyoma.

Utilidad de la tomografía por emisión de positrones con 18F-Fluorodesoxiglucosa combinada con tomografía computarizada en la orientación diagnóstica de la fiebre de origen desconocido / Usefulness of 18FDG PET-CT scan as a diagnostic tool of fever of unknown origin

Fundamento y objetivo: La fiebre de origen desconocido (FOD) se define clásicamente como fiebre de más de 3 semanas, con temperatura superior a 38,3 °C en varias ocasiones y sin diagnóstico definitivo tras una semana de hospitalización. Determinar su etiología es fundamental para establecer un tratamiento adecuado del paciente. Nuestro objetivo es valorar la utilidad de la tomografía por emisión de positrones con 18F-Fluorodesoxiglucosa (18F-FDG) combinada con tomografía computarizada (PET/TC) con fluorodesoxiglucosa marcada con flúor 18 (18F-FDG) en la orientación diagnóstica de la FOD. Material y método: Estudio observacional retrospectivo de exploraciones PET/TC realizadas a 30 pacientes consecutivos con FOD entre marzo de 2010 y septiembre de 2013. El diagnóstico definitivo se alcanzó en 26/30 pacientes (86,67%): 15 con confirmación histológica, microbiológica en un caso y con seguimiento clinicorradiológico (media de 16,38 meses) en 10 pacientes. Resultados: Un total de 23 estudios fueron positivos: 10 con etiología tumoral, 8 inflamatoria, 4 infecciosa y uno miscelánea (100% verdaderos positivos). La PET/TC mostró una eficacia en el enfoque diagnóstico del 90,00%, una sensibilidad del 88,46% (intervalo de confianza del 95% [IC 95%] 76-101), una especificidad del 100,00% (IC 95% 100-100), un valor predictivo positivo del 100,00% (IC 95% 100-100) y un valor predictivo negativo del 57,14% (IC 95% 20-91). Conclusiones: La 18F-FDG PET/TC ha demostrado presentar una elevada sensibilidad y especificidad en el diagnóstico etiológico de la FOD, aportando una información morfofuncional valiosa, especialmente en la localización del lugar óptimo para la toma de biopsias (AU)

Background and objective: Classic fever of unknown origin (FUO) is defined as the presence of fever greater than 38.3 °C of at least 3 weeks with an uncertain diagnosis. Identification of the etiology is crucial in guiding further diagnostic procedures and subsequent patient management. The aim of this study was to evaluate the role of fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography combined with computed tomography (PET/CT) in the diagnostic orientation of FUO. Material and method: An observational retrospective study was performed, including 30 consecutive patients who had been studied between March 2010 and September 2013. Twenty-six out of 30 patients (86.67%) had a definitive diagnosis after pathologic confirmation in 15 cases, microbiological findings in one patient and clinical and radiological follow-up in 10 patients (mean: 16.38 months). Results: Among the positive scans, malignancy (n = 10), inflammatory (n = 8), infectious (n = 4) and miscellaneous causes (n = 1) were identified. 18F-FDG PET/CT had a diagnostic accuracy of 90.00%, sensitivity of 88.46% (95% confidence interval [95% CI] 76-101), specificity of 100.00% (95% CI 100-100), positive predictive values of 100.00% (95% CI100-100) and negative predictive value of 57.14% (95% CI 20-91). Conclusions: 18F-FDG PET/CT provided useful for the etiologic diagnosis of FUO, with high sensitivity and specificity.18F-FDG PET/CT has an incremental morphological and functional value, especially indicating the best biopsy site (AU)

Infección por Anisakis con presentación atípica: a propósito de un caso / Anisakis infection with atypical presentation: Report of a case

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[Usefulness of (18)FDG PET-CT scan as a diagnostic tool of fever of unknown origin]. / Utilidad de la tomografía por emisión de positrones con (18)F-Fluorodesoxiglucosa combinada con tomografía computarizada en la orientación diagnóstica de la fiebre de origen desconocido.

BACKGROUND AND OBJECTIVE: Classic fever of unknown origin (FUO) is defined as the presence of fever greater than 38.3°C of at least 3 weeks with an uncertain diagnosis. Identification of the etiology is crucial in guiding further diagnostic procedures and subsequent patient management. The aim of this study was to evaluate the role of fluorine-18 fluorodeoxyglucose ((18)F-FDG) positron emission tomography combined with computed tomography (PET/CT) in the diagnostic orientation of FUO. MATERIAL AND METHOD: An observational retrospective study was performed, including 30 consecutive patients who had been studied between March 2010 and September 2013. Twenty-six out of 30 patients (86.67%) had a definitive diagnosis after pathologic confirmation in 15 cases, microbiological findings in one patient and clinical and radiological follow-up in 10 patients (mean: 16.38 months). RESULTS: Among the positive scans, malignancy (n=10), inflammatory (n=8), infectious (n=4) and miscellaneous causes (n=1) were identified. (18)F-FDG PET/CT had a diagnostic accuracy of 90.00%, sensitivity of 88.46% (95% confidence interval [95% CI] 76-101), specificity of 100.00% (95% CI 100-100), positive predictive values of 100.00% (95% CI100-100) and negative predictive value of 57.14% (95% CI 20-91). CONCLUSIONS: (18)F-FDG PET/CT provided useful for the etiologic diagnosis of FUO, with high sensitivity and specificity. (18)F-FDG PET/CT has an incremental morphological and functional value, especially indicating the best biopsy site.

La valoración del riesgo asociado a caries / Assessment of risk associated to dental caries

La prevención en los padecimientos crónicos implica tener en consideraciónno sólo el riesgo de que una enfermedad como la caries dental se inicie, sino que se reactive, cuando se da por supuesto que está controlado totalmente. La investigación sobre métodos y técnicas para mejorar la valoración del riesgo asociado a la caries dental permitirá a los cirujanos dentistas y a sus pacientes desarrollar actividades de prevención y control de la caries dental, adecuadas a cada caso particular

n patients with chronic complaints, prevention implies being aware not only of the risk of diseases such as dental caries occurring but also, where dentists assume these have been brought fully under control, of the risk of their recurrence. Research on methods and techniques to improve the assessment of the risk associated with dental caries will allow dental surgeons and patients to develop better and more personalized ways to prevent and control it.

Características clínicas y evolución de los donantes de hígado para trasplante hepático modalidad vivo a vivo / Clinical features and outcome of liver donors for living donor liver transplantation

El trasplante hepático es la única opción terapéutica de los pacientes con enfermedad hepática terminal. El trasplante de donante cadavérico es menos probable en nuestro país. Por esto se desarrolló el programa de trasplante hepático de donante vivo desde el año 2005 en nuestro país. Se revisaron las historias de 39 donantes. Cada donante fue sometido al protocolo de evaluación pretrasplante incluyendo, laboratorio, angiotomografía, colangioresonancia, evaluación psiquiátrica, social y biopsia hepática de ser necesaria. Incluimos 39 individuos entre 18 y 52 años. Solo 9 donantes presentaron complicaciones: 4 colecciones intraabdominales, 4 infecciones de la herida, 2 fístulas biliares, 1 endocarditis, 1 enterocolitis y 1 ameritó reintervención por colección intraabdominal. No se registró mortalidad. Se realizaron 17 hepatectomías laterales izquierdas, 15 izquierdas, y 7 derechas. Posterior a 3 meses los donantes tenían el mismo volumen hepático previo a la donación. Todos están en condiciones físicas satisfactorias y regresaron a sus actividades cotidianas entre 1 y 3 meses después de la donación. La evolución de todos los donantes fue satisfactoria lográndose la reincorporación a sus actividades habituales en corto plazo. El trasplante hepático de donante vivo relacionado es un procedimiento seguro para los donantes

Liver transplantation is the only therapeutic option for patients with end stage liver disease. Liver transplantation from cadaveric donors is less probable in our country. For all this the living donor liver transplantation program was developed in our country since 2005. The medical histories of 39 donors were reviewed. Each donor underwent the pretransplant evaluation protocol that includes laboratory, angioTAC, colangioMRI, psychiatric, social evaluation and hepatic biopsy if necesary. We included 39 individuals with ages between 18 and 52 years. Only 9 donors developed complications: 4 intraabdominal collections, 4 wound infections, 2 biliary fistulae, 1 endocarditis, 1 enterocolitis, and 1 patient needed surgery for an intrabdominal collection. No mortality has been registered. 17 left lateral, 15 left and 7 right hepatectomies were done. After 3 months the donors had the same hepatic volume prior to donation surgery. They are all in excellent physical conditions and have returned to their daily activities within a period between 1 and 3 months after donation. The outcome of each donor was satisfactory being able to return to their daily activities in a short term. Living donor liver transplantation is a safe procedure for donors and constitutes an alternative for our patients that need hepatic transplantation

Transplante hepático pediátrico en Venezuela experiencia preliminar

Introducción y objetivos: el transplante hepático es uno de los tratamientos adecuados en pacientes pediátricos con enfermedades hepáticas en fase terminal. El objetivo del presente trabajo es presentar la experiencia preliminar del programa de transplante hepático pediátrico llevada a cabo en nuestro país. Pacientes y métodos: se incluyeron niños que fueron evaluados en la consulta de pretransplante pediátrico del programa metropolitano de transplante por presentar enfermedades hepáticas en fase terminal Resultados: se incluyeron pacientes a los que se les realizó transplante hepático entre abril de 2005 y marzo de 2007; 9 pacientes en edades comprendidas entre 5 años y 15 años, 3 del sexo masculino y 6 del sexo femenino. Todos los pacientes presentaban serología para CMV positiva previo al transplante y 5 presentaban serología positiva para EBV previa al transplante. Todos los individuos tenían una calificación PELD entre 9 y 17. La enfermedad hepática crónica que los llevó a la necesidad de realizarles transplante hepático incluyó los siguientes diagnósticos: atresia de vías biliares extrahepáticas4, colestasis intrahepática familiar progresiva² y hepatitis autoinmune¹, hepatocarcinoma¹ y fibrosis hepática congénita¹. A 7 de los pacientes se les realizó transplante hepático de donante vivo, 1 de donante cadavérico y 1 autotransplante. El tiempo de estadía en terapia intensiva fue de 11 a 30 días, y el tiempo posterior en hospitalización fue de 3 a 15 días. El esquema de inmunosupresión inicial fue ciclosporina, prednisona, micofenolato a 4 pacientes y 5 tacrolimus y prednisona. Dos pacientes presentaron rechazo agudo el cual fue tratado con bolus de esteroides por 3 días con resolución completa de la disfunción del injerto. Todos los pacientes presentaron complicaciones infecciosas en los primeros 6 meses del postransplante, entre ellas: 4 pacientes infecciones urinarias documentadas por urocultivo por Proteus Mirabilis 2 y E. Coli 2, 5 pacientes presentaron infecciones por CMV a los cuales se les administró valganciclovir por vía oral obteniendo una respuesta adecuada. Dos de los pacientes presentaron complicaciones neurológicas, 1 presentó convulsiones tónico clónicas generalizadas sin déficit neurológico, se le realizó TAC y EEG los cuales resultaron normales con niveles elevados de ciclosporina y niveles bajos de magnesio que fueron corregidos. Un paciente presentó alucinaciones, se le realizó TAC cerebral y EEG normal, recibió haloperidol durante un período de 3 meses, con evolución satisfactoria. Uno de los pacientes presentó complicación biliar a los 9 meses postransplante, demostrada por ecografía abdominal y colangioresonancia (estenosis de la vía biliar), se colocó prótesis biliar con mejoría completa del funcionalismo hepático. Un paciente con síndrome hepatopulmonar previo al transplante, amerito para su corrección final, después del trasplante de tratamiento endovascular del shunt AV, arteria pulmonar lóbulo inferior izquierdo con colocación de espirales de titanium con resolución de la hipoxemia persistente. Posteriormente, ese mismo paciente presentó vasoespasmo de la arteria hepática documentado por perdida del registro arterial durante evaluación doppler y acompañado de elevación de las aminotranferasas recibiendo tratamiento con nitroglicerina intrarterial y colocación de stent con mejoría completa del funcionalismo hepático. La sobrevida del injerto y de los pacientes es en la actualidad de un 100%. Conclusión: el transplante hepático constituye hoy en día en Venezuela una posibilidad terapéutica para los pacientes pediátricos con enfermedad hepática terminal, progresiva e irreversible, que no está exento de complicaciones pero que al ser diagnosticadas y tratadas a tiempo, alcanza un 100% de sobrevida tanto del injerto como de los pacientes.

Introduction and Objectives: Liver transplantation is the treatment of choice for pediatrics patients that suffer end stage liver disease (ESLD). The goal of this essay is to introduce the first national experience with the modality of liver pediatric transplantation programs in the treatment of ESLD in pediatrics patients. Patients and Methods: 9 children suffering ESLD and their respective donors were seen between April 2005 and May 2007, each patient and its donor underwent a complete transplant evaluation (cardiac, respiratory, renal evaluation, imaging studies, and blood work up) to determine their candidate for either liver transplant recipient, or liver donor. RESULTS: 9 patients in ages between 5 years and 15 years, 3 male and 6 were included. All the patients had positive serology for CMV before transplant and 5 had positive serology for EBV before transplant. All the patients had score PELD 9 and 17. Diagnoses of the recipients were as follow: 4 Atresias of extrahepatic biliary tract, 2 progressive familiar intrahepatic cholestasis, 1 autoimmune hepatitis, 1 congenital fibrosis and 1 hepatocarcinoma. 7 live donor liver transplants, 1 deceased donor and 1 autologous liver transplant were performed. Operative mortality was 0%. Patient and graft survival were 100% at 1 and 2 years follow up. Patients presented various complications that included: acute rejection, CMV infection, acute urinary tract infections, hepatic artery spasm, and seizures among others. All the previous mentioned complications were successfully treated. Conclusion: Liver transplant constitutes the best option for the patient with ESLD, early referral is critical in the outcome of pediatric patients that need liver transplant.

Integrated pharmacokinetic-pharmacodynamic modeling and allometric scaling for optimizing the dosage regimen of the monoclonal ior EGF/r3 antibody.

The multiple-dose strategy with the monoclonal ior EGF/r3 antibody, in xenograft bearing nude mice, was supported upon the basis of its integrated pharmacokinetic-pharmacodynamic relationship, according to both the temporal (K(e0)=0.0015+/-0.000035h(-1)) and the time-independent sensitivity (C(50%)(ss), 9.23+/-0.17microg/ml; C(max,eff)(ss), 12.5microg/ml) components of its tumor growth delay action. This relationship was consistent with a sigmoidal E(max) pharmacodynamic model postulating a hypothetical effect compartment that permits us to estimate an effective steady-state concentration range (7.5-12microg/ml). Using this information we calculated both the cumulative and non-cumulative dosage regimens to compare their response patterns with respect to the control group. It follows that the differences in the estimated tumor growth inhibition ratio were statistically significant between the control group and either of the treated ones (P<0.05). The median survival time in treated mice under non-cumulative regimen (72+/-10 days), predicted an increase in this parameter as compared to the control one (55+/-6 days). Finally, using the allometric paradigm, the empiric power equation for dose scaling across mammalian species allowed the calculation of the dosage schedule for further clinical trial. The estimated maintenance dose in human (70kg) was 200mg/m(2) to be given weekly, and the corresponding loading dose was 600mg/m(2).

Qué es púrpura fulminante asociada a sepsis en niños / What is purpura fulminants asociated to sepsis in children

La púrpura fulminante es un síndrome que se caracteriza por un inicio agudo y progresivo de hemorragia cutáneas, trombosis intravascular, necrosis, así como también coagulación intravascular diseminada, que puede presentarse en varias entidades clínicas, destacándose en la edad pediátrica las causas infecciosas. Presentamos 6 casos clínicos de púrpura fulminante asociada a sepsis que fueron tratados en la Unidad de Cuidados Intensivos Pediátrica desde diciembre 1998 a diciembre 2001. Además de las medidas de soporte, todos requirieron debridamiento, fasciotomías, apósitos biológicos, injertos de piel y amputaciones. Dos pacientes fallecieron

Colgajo submental como alternativa para la reconstrucción de un defecto de labio inferior y menton, en un paciente con carcinoma basocelular / Submental island flaps, alternative for reconstruction a defect of liplower in patient witch basocelullar

La reconstruccíon de los defectos postquirúrgicos de la región anterior de la cabeza y el cuello después de la extirpación de neoplasias de la piel o de las vísceras cervicales, presenta un reto para los cirujanos implicados en el tratamiento de este tipo de pacientes. Se presenta a continuación el caso clínico de un paciente al cual se le extirpó un carcinoma basocelular de la piel del mentón, que ameritó la reconstrucción del defecto con un colgajo rotado miocutáneo de la región submentoniana basado en la arteria submental derecha, obteniendo un excelente resultado funcional y estético. Conocer la anatomía de la región suprahioidea es esencial para la disección del colgajo submental y la prevención de las lesiones de las estructuras que discurren a dicho nivel. El colgajo submental provee tejido para una amplia cobertura del rostro, posee las mismas características en cuanto a color y textura del área receptora de la cara, por lo que creemos que es una excelente alternativa para la reconstrucción en un solo tiempo de los defectos postquirúrgicos de la cirugía de cabeza y cuello