Ingenieria y ciencias de la vida: Relación simbiótica para la supervivencia humana / Engineering and Life Sciences: Symbiotic relationship for the human survival / Engenharia e Ciências da Vida: Relação simbiótica para a sobrevivência humana

RESUMEN Aunque los desarrollos que surgen del trabajo conjunto entre ingenieros y científicos de la vida han aumentado y mejorado en las últimas décadas, todavia hay muchas cosas que hacer en esta relación. Una de ellas es la mejora urgente del sistema de salud, porque si bien la tecnologia es importante para mejorar el diagnóstico y el tratamiento, también es necesario superar los complejos problemas de cobertura, calidad, equidad y atención oportuna que sufren los pacientes en muchas partes del planeta. Los gobiernos deben tener el presupuesto adecuado para satisfacer las necesidades en salud de sus ciudadanos y fortalecer el sistema para ampliar la cobertura y mejorar su calidad. Estas son tareas pendientes que deben abordarse desde la experiencia de la ingenieria para gestionar y organizar sistemas, en un trabajo armonioso con científicos de la salud e involucrando a pacientes, médicos, gobiernos, fabricantes, otras disciplinas y la sociedad en general.

AВSTRАСT Although the developments that arise from the joint work between engineers and life scientists have increased and improved in recent decades, there are still many things to do in this relationship. One of them is the urgent improvement of the health system because although technology is important to improve diagnosis and treatment, it is also necessary to overcome the complex problems of coverage, quality, equity and timely attention that patients suffer in many parts of the planet. Governments need to have the appropriate budget to meet the health needs of their citizens and strengthen the health system to expand coverage and improve its quality These are pending tasks that must be addressed from the experience of engineering to manage and arrange systems, in harmonious work with health scientists and involving patients, doctors, governments, manufacturers, other disciplines and society in general.

RESUMO Embora os desenvolvimentos decorrentes do trabalho conjunto entre engenheiros e cientistas da vida tenham aumentado e melhorado nas últimas décadas, ainda há muito a ser feito nesta relação. Uma delas é a melhoria urgente do sistema de saúde, pois embora a tecnologia seja importante para melhorar o diagnóstico e o tratamento, também é necessário superar os complexos problemas de cobertura, qualidade, eqüidade e cuidado oportuno que os pacientes sofrem em muitas partes do mundo. Os governos devem ter orçamentos adequados para atender às necessidades de saúde de seus cidadãos e fortalecer o sistema para expandir a cobertura e melhorar a qualidade. Estas são tarefas pendentes que devem ser abordadas pela engenharia especializada para administrar e organizar sistemas, trabalhando harmoniosamente com cientistas da saúde e envolvendo pacientes, médicos, governos, fabricantes, outras disciplinas e a sociedade em geral.

[Risk factors and frequency in re-ruptures of the anterior cruciate ligament in adults]. / Factores de riesgo y frecuencia de rerrupturas del ligamento cruzado anterior en adultos.

BACKGROUND: The anterior cruciate ligament (ACL) takes part in the knees articular cinematic regulation, which is why its rupture should be repaired as soon as possible. The surgical treatment is targeted to substitute the ruptured ACL with a graft that recreates the anatomical and biomechanical functions. Nevertheless, there are different factors that may produce a second rupture. OBJECTIVE: To determine the risk factors and frequency of failure in the ACL reconstruction. MATERIAL AND METHODS: Retrospective study evaluating the frequency and etiology of the failure in the ACL reconstruction in an adult population during a three-year period. Risk factors such as age, gender, trauma background, previous joint injuries, type of the graft previously used, lapse between surgeries, lapse between rupture and surgery and other comorbidities were analyzed. RESULTS: We obtained 34 patients with ACL reconstruction failure and 111 with native ACL rupture (145 patients in total). In the ACL reconstruction failure group, 31 were males with an average age of 33 years, produced by a traumatic mechanism (85.2%) and with other associated injuries (41%). CONCLUSIONS: We found a significant statistical association for graft failure with male patients, traumatic mechanism, isolated cartilage lesions or combined articular injuries.

El ligamento cruzado anterior (LCA) participa en la regulación de la cinemática articular de la rodilla, por lo que su ruptura debe repararse lo antes posible. El tratamiento quirúrgico está encaminado a la sustitución del LCA roto por un injerto que lo reemplazará tanto anatómica como biomecánicamente. Sin embargo, se pueden presentar diferentes condiciones que produzcan una rerruptura.

Validation of the HIV Tropism Test TROCAI Using the Virological Response to a Short-Term Maraviroc Monotherapy Exposure.

TROCAI is a phenotypic tropism test developed using the virological response to a short-term exposure to maraviroc monotherapy (Maraviroc Clinical Test [MCT]). It was found that with TROCAI, a cutoff of <0.5% of dual/mixed viruses was needed to predict R5 HIV tropism. Here, we have validated TROCAI, using this cutoff, in a new cohort of 42 patients, finding a very high concordance between TROCAI and MCT (98%), and a good concordance (71 to 87%) with other genotypic/phenotypic methods.

Ciencia y disciplinariedad

En el transcurrir de la historia de la ciencia, se presentan diversos momentos en los que sus protagonistas han dejado su legado impreso. Aunque el dinamismo de la ciencia no permite su estancamiento en el tiempo, cada era la impregna de hechos, realidades y coyunturas que se deben analizar desde una mirada analítica e imparcial. En este artículo se presenta uno de esos análisis con el objetivo de definir qué es y qué no es ciencia, y se intenta responder al interrogante de para qué se hace ciencia, todo con una visión de disciplinariedad científica.

In the course of history of science had presented many times when its protagonists have left their legacy printed. Although the dynamism of science does not allow stagnation in time, each was impregnated with facts, realities, and situations that should be analyzed from an analytical and unbiased look. This article presents one such analysis to define what is and is not science, and attempts to answer the question of what is science done for all from a vision of scientific disciplinarity.

No curso da história da ciência tinha apresentado muitas vezes quando seus protagonistas não deixaram o seu legado impresso. Embora o dinamismo da ciência não permite que a estagnação no tempo, cada um foi impregnado com fatos, realidades e situações que devem ser analisados a partir de um olhar analítico e imparcial. Este artigo apresenta uma tal análise para definir o que é e não é ciência, e tenta responder À questão sobre o que é ciência feita para, tudo a partir de uma visão de disciplinaridade científica.

Single fraction volumetric modulated arc radiosurgery of brain metastases.

PURPOSE: To show the clinical results of the treatment of brain metastases via radiosurgery using Volumetric Modulated Arc Therapy (VMAT). MATERIALS AND METHODS: 52 patients having lung (62 %), breast (17 %), colorectal (8 %) and other cancers (13 %) with one to three brain metastases were treated with 5 non-coplanar VMAT arcs. The treatment dose varied from 12 to 20 Gy, administered in one single session. The volume of metastases ranged from 0.04 to 24.92 cc. Radiosurgery alone was used for 54 % of cases, while 19 % received whole brain radiotherapy due to relapse. Patients were classified according to the Disease-specific graded prognostic assessment (DS-GPA) index and survival was assessed via the Kaplan-Meier model. RESULTS: The median survival time was 7.2 months from the date of radiosurgery. The Karnofsky and DS-GPA indices were the most significant with regard to survival. Patients with a Karnofsky performance status (KPS) over 70 had a longer survival time of 9.2 months, as opposed to those with a KPS below 70 of 3.5 months. No significant differences were found with regard to the type of cancer or the number of lesions. Local tumour control was achieved for 42 metastases (82 %), of which a complete response was achieved for 7 lesions, a partial response for 21; 15 lesions were stabilized. Local progression was observed in 8 lesions (15 %). The median treatment time per patient was 29 min. CONCLUSIONS: The VMAT technique proves to be safe and effective for treating brain metastases via radiosurgery.

[Mortality and morbidity in very low birth weight infants in the Basque Country and Navarra (2001-2006): population-based study]. / Mortalidad y morbilidad de neonatos de muy bajo peso asistidos en el País Vasco y Navarra (2001-2006): estudio de base poblacional.

INTRODUCTION: This study describes very low birth weight (VLBW) infant morbidity and mortality in Basque Country and Navarra neonatal units between the years 2001-2006, and evaluates the factors that affect the mortality. PATIENTS AND METHODS: A descriptive observational study of a cohort of 1,318 VLBW infants in neonatal units in five Basque Country and Navarra hospitals between 2001 and 2006. A total of 37 variables included in EuroNeoNet database were collected as regards, perinatal risk and protective factors, demographic characteristics, length of stay, interventions, morbidity and mortality. RESULTS: A total of 94% of pregnant women received prenatal care and 78.7% antenatal steroids. In both cases there was a significant increase during the period studied. A total of 42% of pregnancies were multiple and in 63% delivery was by Caesarean section. Bronchopulmonary dysplasia statistically significantly decreased from 20% to 15%. The incidence of intraventricular haemorrhage grade III or IV was 7.5% and for periventricular leukomalacia it was 3.1%. Vertical infection was diagnosed in 4% of infants and sepsis or late meningitis in 25%, necrotizing enterocolitis in 9% and patent ductus arteriosus in 14% of the infants. The prophylactic or therapeutic treatment with indometacin or ibuprofen decreased significantly during the study. The overall rate of total, late and first day neonatal mortality was almost constant during this period of time. Nevertheless, the early neonatal mortality showed a decreasing trend and with a significant difference between sexes, being higher in males. CONCLUSION: This population-based study provides valuable information on clinical outcomes in NICUs, and may help in planning strategies to improve health care quality, and to reduce the morbidity and mortality in these neonates at high risk.

Histerectomía laparoscópica total: manejo ambulatorio: experiencia Clínica del Prado, Medellín, Colombia / Outpatient total laparoscopic hysterectomy

Objetivo: Describir los resultados de la histerectomía laparoscópica total ambulatoria. Método: Se analizan 297 pacientes sometidas a histerectomía laparoscópica total y que fueron dadas de alta luego de la recuperación anestésica, entre mayo de 2007 y marzo de 2008. Se requería una puntuación de menos de 5 en la escala visual análoga del dolor para el alta. Resultados: El promedio de edad fue de 42 años, el tiempo quirúrgico de 79,1 minutos, el sangrado estimado fue de 37,1 ml, el tiempo promedio de estancia total fue de 9,4 horas con un tiempo promedio de estancia postoperatoria de 5,4 horas. La tasa de complicaciones postoperatorias fue de 11,8 por ciento y la de readmisiones del 3,3 por ciento. El promedio de Escala Visual Análoga del dolor para la primera noche fue de 4,2 puntos. El 6 por ciento de las pacientes presentaron vómitos en su domicilio. El 99 por ciento de las pacientes recomendarían este tipo de manejo. Conclusiones: El manejo ambulatorio después de histerectomía laparoscópica total es posible, seguro y bien evaluado por las pacientes. Este manejo no conlleva un mayor riesgo de complicaciones y la tasa de readmisiones es baja.

Objective: To describe the results of a group of patients in which total laparoscopic hysterectomy was done as an outpatient procedure. Methods: We included 297 patients who were undergone to laparoscopic total hysterectomy, and were discharge to their home after recovery of anesthesia from may 2007 to march 2008. It was necessary to have a punctuation less than 5 in the analogue visual scale to be sent at home. Results: Mean age was 42 years, surgical time 79.1 minutes, estimated blood loss 37.1 ml, overall length of stay 9.4 hours, postoperative length of stay 5.4 hours. Postoperative complication rate was 11.8 percent, readmission rate was 3.3 percent. Mean VAS Score for pain during the first night was 4.2 points; 6 percent of patients vomited at home. Mean VAS Score for satisfaction with ambulatory management was 9.5, and 99 percent of the patients would recommend this type of management. Conclusions: Ambulatory management after total laparoscopic hysterectomy is possible, safe and well evaluated by patients. It does not impose a higher risk of complications and readmission rate is low.

Cistouretropexia laparoscópica tipo Burch para el tratamiento de la incontinencia urinaria de esfuerzos: seguimiento a largo plazo / Laparoscopic Burch colposuspension for the treatment of stress urinary incontinence

Objetivos: Conocer las complicaciones, las tasas de cura subjetiva y valoración con el índice de severidad de Sandvik a largo plazo de pacientes en quienes se realizó cistouretropexia laparoscópica tipo Burch para la corrección de su incontinencia urinaria de esfuerzo (IUE). Método: Análisis descriptivo, retrospectivo. Nivel de evidencia III. Se incluyeron las pacientes con diagnóstico de IUE tipo Blaivas IIB, a quienes se les practicó Burch laparoscópico en la Clínica del Prado y Profamilia Medellín, entre los años 2003 y 2007. Las variables principales a evaluar fueron edad, tiempo quirúrgico, cura subjetiva, índice de severidad de Sandvik y complicaciones. Resultados: Se analizaron 72 pacientes con promedio de edad de 46,57 +/- 9,54 años. El tiempo promedio de seguimiento fue de 24,4 meses (rango: 9,0-55,8 meses). El tiempo quirúrgico promedio fue de 79,83 minutos (rango: 44-160 minutos). Refirieron cura subjetiva 56 pacientes (77,8 por ciento). El índice de severidad de Sandvik muestra que a largo plazo 56,9 por ciento pacientes estaban secas con remisión completa de los síntomas y el 13,8 por ciento pacientes tenían pérdidas leves. Conclusiones: El Burch laparoscópico es una opción efectiva para el manejo de la incontinencia urinaria de esfuerzo tipo Blaivas IIB. Provee tasas de curación subjetiva a largo plazo similares a otros tipos de tratamiento. Es una opción más a tener en cuenta en el manejo de la IUE, en especial aquellas pacientes con patologías asociadas que se beneficien del abordaje por laparoscopia.

Objectives: To describe the subjective cure rate, the score of the Sandvik test and the complications after laparoscopic Burch in patients with stress urinary incontinence (SUI). Methods: Prospective descriptive study. We included all patients diagnosed with SUI Blaivas type IIB, and operated on by laparoscopy in two reference institutions between 2003 and 2007. Results: We analyzed 72 patients with an average age of 46.57 +/- 9.54 years. The average follow-up was 24.4 months, with a minimum of 9 and a maximum of 55.8. The average operating time in 29 patients in which we only performed laparoscopic Burch with or without colporrhaphy was 93.7 minutes (55-180 minutes); 56 patients (77.8 percent) reported subjective cure. The Sandvik's severity index found 56.9 percent dry patients and 13.8 percent with mild losses. Conclusion: The laparoscopic management may be useful in some patients, especially those who will be carried to laparoscopy by some other indication. Subjective cure rates are similar to other types of surgery.

Histerectomía laparoscópica total, curva de aprendizaje: experiencia de Clínica del Prado, Medellín, Colombia / Total laparoscopic hysterectomy and learning curve: experience of Clínica del Prado, Medellín, Colombia

Objetivos: Comparar la curva de aprendizaje en histerectomía laparoscópica total (HLT) de 4 ginecólogos en la Clínica del Prado, Medellín, Colombia. Determinar el número de cirugías necesarias para alcanzar un tiempo quirúrgico promedio de 90 minutos, disminuir la laparoconversiones a un 3 por ciento o menos y disminuir las complicaciones totales a menos del 10 por ciento. Método: Se realizó un estudio de cohorte prospectivo que incluyó 626 pacientes operadas por 4 ginecólogos laparoscopistas con técnica y equipamiento quirúrgico similar. Se formaron 4 grupos de pacientes de acuerdo al orden en la casuística de cada uno de ellos. Resultados: El tiempo quirúrgico promedio de 93 minutos se logra con las primeras 50 HLT. El realizar entre 50-100 HLT baja las tasas de laparoconversión a 1,9 por ciento. La tasa de complicaciones en la sumatoria de la primera y segunda cohorte es de 19,4 por ciento y la tasa de complicaciones totales en la tercera cohorte es de 8,7 por ciento (RR: 0,45; IC95 por ciento: 0,26-0,78) la cual permanece en el límite deseado (10 por ciento) en la cuarta cohorte. Conclusiones: La curva de aprendizaje en HLT para lograr un promedio de tiempo de cirugía de 90 minutos se logra con las primeras 50 histerectomías. A pesar de las limitaciones metodológicas, el presente estudia revela que para lograr la destreza máxima toma entre 50-100 histerectomías para lograr laparoconversiones menores del 3 por ciento y entre 100-150 histerectomías para lograr complicaciones totales inferiores a 10 por ciento.

Objective: To compare the learning curve in total laparoscopic hysterectomy (HLT) from four gynecologists in the Clínica del Prado, Medellín, Colombia. To determine the number of surgeries required to achieve an average surgical time of 90 minutes, to reduce laparoconversions to 3 percent or less and to reduce total complications to less than 10 percent. Method: We performed a prospective cohort study including 626 patients operated by four gynecologists laparoscopist with similar technique and surgical equipment. We made four groups of patients according to the order in the cases of each one. Results: The mean operative time of 93 minutes is achieved with the first 50 HLT. Doing 50-100 HLT, laparoconversions rates low to 1.9 percent. The complication rate in the sum of first and second cohort is 19.4 percent and the total complication rate in third cohort is 8.7 percent (RR: 0.45; 95 percentCI 0.26-0.78) which remains in the desired limit (10 percent) in fourth cohort. Conclusions: HLT learning curve to achieve an average surgical time of 90 minutes is achieved with the first 50 hysterectomies. Despite the methodological limitations this study, shows that to achieve máximum expertise, it takes between 50-100 hysterectomies to achieve laparoconversions less than 3 percent, and between 100-150 hysterectomies to achieve total complications lower than 10 percent.

Localization and quantification of carbon-centered radicals on any amino acid of a protein.

A general strategy to localize and quantify carbon-centered radicals within proteins is described. The methodology was first exemplified on amino acids and then on a peptide. This method is applicable to any protein system regardless of size, and the site of hydrogen abstraction by *OH on all residues within proteins is easily and accurately detected.

Protocolo de manejo de pancreatitis aguda. Hospital Universitario San Ignacio (HUSI) Bogotá / Acute Pancreatitis Protocol, Hospital Universitario San Ignacio (HUSI), Bogotá

La pancreatitis aguda es la inflamación aguda del páncreas con grado variable de compromiso de los tejidos regionales y diferente grado de compromiso sistémico. Se utilizan como definiciones las establecidas en el consenso de Atlanta (anexo 1). B. Diagnóstico 1. Historia clínica. Se presenta dolor en hemiabdomen superior, usualmente serio y acompañado de grados variables de vómito, náuseas y fiebre. Son importantes los antecedentes personales y familiares. 2. En el examen físico siempre se deben incluir el peso, la talla, el índice de masa corporal (IMC), la temperatura, la saturación de oxígeno (SAO2), la frecuencia cardiaca, la frecuencia respiratoria y la tensión arterial.

[Thyroid dysfunction in women with suspected fibromyalgia]. / Disfunción tiroidea en mujeres con sospecha de fibromialgia.

BACKGROUND AND OBJECTIVE: Due to its prevalence, morbidity, and frequency rate, fibromyalgia (FM) represents a health problem and produces high healthcare resource utilization. Serum thyrotropin (TSH) measurement is recommended as a first-line laboratory test to exclude hypothyroidism as a cause of FM syndrome. The aim of this study was to analyze the prevalence of thyroid dysfunction (TD), the frequency of TSH measurement, the effect of levothyroxine treatment, and whether screening for TD is justified in women with suspected FM. PATIENTS AND METHODS: A cross-sectional descriptive study was performed in 400 consecutive female outpatients with suspected FM and in 384 controls from January 2001 to October 2004. TSH measurement was used as the first line test to detect TD. RESULTS: The prevalence of TD in patients with suspected FM (40/400; 10%; 95% CI: 7-13%) and controls was similar (46/384; 12%; 95% CI: 9-15%). No differences were found in the types and grades of TD. The prevalence of TD was higher in patients with suspected FM and connective tissue diseases (12%) than in those without these diseases (5%). The most frequent TD was subclinical hypothyroidism (5.5% in suspected FM and 6.7% in controls), and in 93% of these cases TSH concentrations were <10 mIU/L. FM persisted in all women with hypothyroidism even after euthyroidism was achieved with levothyroxine. A total of 870 TSH determinations were performed in 360 euthyroid patients with suspected FM. CONCLUSIONS: The prevalence of TD in women with suspected FM does not differ from that in the general population. Screening for TD does not appear to be justified in women without diseases that increase their risk. In many cases the request for thyroid function tests is excessive. Treatment for hypothyroidism does not affect FM.

Modulation of cell cycle by graded expression of MLL-AF4 fusion oncoprotein.

Acute lymphoblastic leukemia (ALLs) expressing MLL-AF4, the fusion product of t(4;11)(q21;q23), show marked leucocytosis and extramedullary disease in multiple organs, respond poorly to chemotherapy and have poor prognosis. In vitro, leukemic cells with the t(4;11) show resistance to serum deprivation-induced or interferon gamma-regulated CD95-mediated apoptosis. In addition, t(4;11) cells have prolonged doubling time and lower percentage of cells in cycle compared to non-t(4;11) B lineage cell lines. In this study, we examine the time- and level-dependent effects of MLL-AF4 conditional expression on cell cycle and differentiation of myelomonocytic leukemia cell line U937. By varying the concentration of tetracycline in growth media, we found that increasing levels of MLL-AF4 expression result in a progressive decrease in growth rate and fraction of S phase cells, paralleled by an increase in percentage of cells expressing CD11b. Our results demonstrate a dosage-dependent effect of MLL-AF4 fusion oncoprotein on cell cycle progression, with increasing expression levels resulting in the accumulation in G1, prolonged doubling time, both findings that might be responsible for the increased resistance to etoposide-mediated cytotoxicity. We propose the cell cycle control exerted by MLL-AF4 may be responsible of resistance to cell-death promoting stimuli in leukemia carrying the t(4;11) translocation.

The effect of AH 26 and AH Plus on MCF-7 breast cancer cell proliferation in vitro.

AIM: The purpose of this study was to determine whether AH 26 and AH Plus have in vitro oestrogenic effects. METHODOLOGY: MCF-7 breast cancer cells were trypsinized and plated in 24-well plates at initial concentrations of 10,000 cells per well in 5% FBS in DME. Cells were allowed to attach for 24 h; then the seeding medium was replaced with 10% CDHuS-supplemented phenol red-free DME. Different concentrations of the test compound were added to sample wells (AH 26 and AH Plus at 1/100 to 1/1,000,000 dilutions), 10 pM estradiol-17beta to positive controL and no sub-stance to negative control (hormone-free control cells). The assay was stopped after 144 h. RESULTS: AH 26-powder induced MCF-7 cell proliferation in a dose-dependent manner. The cell yield obtained with AH 26-powder at 1/100 dilution sample was 2.5-fold greater than in control cultures. The sam-ple prepared with mixed AH 26 paste/powder 1:1 also induced MCF-7 cell proliferation, but showed less potency than AH 26-powder alone. The cell yield obtained with AH 26 paste/powder at 1/100 dilution sample was 1.9-fold greater than in control cultures. AH Plus did not show in vitro oestrogenic effect. CONCLUSIONS: AH 26 showed in vitro oestrogenic effect, but not AH Plus. The endodontist must consider the possible oestrogenic effect of AH 26, as well as the cytotoxic effects of root filling materials, and avoid the leakage of sealer through the apex during root canal treatment.

A transcript encoding a nucleic acid-binding protein specifically expressed in maize seeds.

A cDNA clone has been obtained for a low-abundance, seed-specific mRNA that encodes a polypeptide which defines a novel family of plant proteins with some similarities to the DnaJ class of molecular chaperones. The MEM1 (Maize Endosperm Motif binding protein) protein is capable of binding to the endosperm motif and activating transcription in the yeast one-hybrid system. Recombinant MEM1 was shown to bind in vitro to nucleic acids, with a preference for RNA over DNA. MEM1 is capable of forming homodimers, a property that is dependent on a domain close to the C-terminus of the protein. The protein is expressed in mid- to late-term endosperm cells. Subcellular fractionation and size fractionation under non-denaturing conditions indicate that the protein is present in the cytosol of endosperm cells. Possible roles of MEM1 in endosperm and protein body development are discussed.

Isolation and characterization of two novel retrotransposons of the Ty1-copia group in oat genomes.

Two repetitive sequences, As32 and As22, of 826 and 742 bp, respectively, were isolated from Avena strigosa (As genome). Databank searches revealed their high homology to different segments of the family of Ty1-copia retrotransposons. Southern hybridization showed them to be present in diploid and polyploid oat species. Polymerase chain reaction with primers designed to amplify the segment between them showed that As32 and As22 sequences are composed of two different Ty1-copia retrotransposons. The segment amplified from the pAs32 insert was 2,264 bp long and contained the entire GAG and AP domains, and more than half of the IN domain. This new element has been designated TAS-1 (transposon, A. strigosa, 1) and appears to contain a long open reading frame that encodes a polypeptide of 625 amino acids. Slot-blot and fluorescence in situ hybridization analyses revealed it to be a component of both A- and D-genome chromosomes. Further, the chromosomes involved in one C-A intergenomic translocation in A. murphyi (AC genomes), one C-D intergenomic translocation in A. byzantina cv. Kanota (ACD genomes), and two C-D intergenomic translocations in A. sativa cv. Extra Klock, were identified. Based on its physical distribution and Southern hybridization pattern, a parental retro-transposon represented by TAS-1 appears to have been active at least twice during the evolution of the genomes in species of Avena.

Determining the optimal time for consolidation after distraction osteogenesis.

The consolidation period, one of the biological factors participating in the distraction osteogenesis phenomenon, has not been elucidated. Parameters to assess new bone formation and consolidation in craniofacial distraction have been borrowed from the orthopedic experience. Up until now, the decision to discontinue distraction has been based more on personal experience than on objective data. By using Scintigraphy with Tc99 DP a method has been developed to accurately assess the termination of the consolidation phase. Scintigraphic evidence of consolidation was seen between the fourth and the fifth week after terminating distraction in infants (younger than 12 months). Not before the 10th week in children and between the 10th and the 14th week in adolescents and adults. The data roughly correlates with previous reports. It is believed that the consolidation period should be addressed in biologic terms and not in radiologic terms as done up until now. A method is proposed that offers objective qualitative and quantitative data for the noninvasive evaluation of bone consolidation which could have further applications in distraction of the craniofacial skeleton.

Nutritional and immunologic evaluation of patients with gastric cancer before and after surgery.

The main objective was to evaluate a patient's immunologic and nutritional status as a prognostic indicator of morbidity and mortality in patients with gastric cancer. A prospective clinical study carried out at the National Cancer Institute in Bogotá, Colombia. Our study group consisted of 40 patients with a diagnosis of gastric adenocarcinoma that was treated surgically. Blood samples were taken before and 5 d after surgery; mononuclear cell typing was done by flow cytometry allowing a bicolor analysis. Nutritional evaluation was obtained through measurement of albumin levels, average weight loss, and nutritional risk index (NRI). Half of the malignancies were localized to the middle and lower third of the stomach: stage I, 17.55%; stage II, 10%; stage III, 55%; and stage IV, 17.5%. Twenty subtotal gastrectomies, 11 total gastrectomies, 7 gastrojejunostomies, and 2 esophagogastrectomies with D1 and D2-D3 lymph node resection were performed. A postoperative morbidity of 22.5% and a mortality of 7.5% were observed. A preoperative cellular immunosuppression was identified, with a helper lymphocyte (CD4) to suppressor/cytotoxic lymphocyte (CD8) ratio of 1.38 normal value (NV > 1.5), which increased according to the stage of the disease. Patients who died presented with a significantly greater preoperative cellular immunosuppression than those who survived (P = 0.05). Postoperative mortality correlated significantly with hypoalbuminemia (P = 0.008). In those who died, weight loss was greater than in those who survived (P = 0.06). Patients with severe malnutrition had greater postoperative mortality according to the NRI. Severe preoperative cellular immunosuppression (CD4/CD8 < 1), hypoalbuminemia, weight loss, and severe NRI have a positive predictive value for mortality in patients with gastric cancer.