Immunochemical Recognition of Bothrops rhombeatus Venom by Two Polyvalent Antivenoms.

The protein profile of Bothrops rhombeatus venom was compared to Bothrops asper and Bothrops atrox, and the effectiveness of antivenoms from the National Institute of Health of Colombia (INS) and Antivipmyn-Tri (AVP-T) of Mexico were analyzed. Protein profiles were studied with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and reverse-phase high-performance liquid chromatography (RP-HPLC). The neutralizing potency and the level of immunochemical recognition of the antivenoms to the venoms were determined using Western blot, affinity chromatography, and enzyme-linked immunosorbent assay (ELISA). Bands of phospholipase A2 (PLA2), metalloproteinases (svMPs) I, II, and III as well as serine proteinases (SPs) in the venom of B. rhombeatus were recognized by SDS-PAGE. With Western blot, both antivenoms showed immunochemical recognition towards PLA2 and svMP. INS showed 94% binding to B. rhombeatus venom and 92% to B. asper while AVP-T showed 90.4% binding to B. rhombeatus venom and 96.6% to B. asper. Both antivenoms showed binding to PLA2 and svMP, with greater specificity of AVP-T towards B. rhombeatus. Antivenom neutralizing capacity was calculated by species and mL of antivenom, finding the following for INS: B. asper 6.6 mgV/mL, B. atrox 5.5 mgV/mL, and B. rhombeatus 1.3 mgV/mL. Meanwhile, for AVP-T, the following neutralizing capacities were found: B. asper 2.7 mgV/mL, B. atrox 2.1 mgV/mL, and B. rhombeatus 1.4 mgV/mL. These results show that both antivenoms presented similarity between calculated neutralizing capacities in our trial, reported in a product summary for the public for the B. asper species; however, this does not apply to the other species tested in this trial.

Analysis of the protein profile of the venoms of snakes Bothrops asper, Bothrocophias myersi and Crotalus durissus from the Colombian Andean Region obtained by RP-HPLC / Análisis del perfil proteico de los venenos de Bothrops asper, Bothrocophias myersi y Crotalus durissus serpientes de la Región Andina en Colombia obtenidos por RP-HPLC

ABSTRACT Snake venoms comprise a highly complex mixture of proteins, and there is also a high interspecific and intraspecific variability in their composition, even in the same region. Our aim was to compare the composition of the venoms of Bothrocophias myersi, Crotalus durissus, and Bothrops asper, snakes from the Colombian Andean region by Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC). The venoms were given to the research group under an agreement with Fundación Zoológica de Cali. The venoms pool was obtained by manual extraction, lyophilized and frozen. The venom protein was quantified by direct measurement with Nanodrop® 280 nm. The protein composition was established by RP-HPLC, using a Lichosper 100 RP, C18 column (250X4 mm) with a pore size of 5-m, as well as by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). The highest quantity of protein was found in the venom of B. myersi (108.6 mg/ mL) followed by C. durissus (78.1 mg/mL) and B. asper (74.1 mg/mL). All venoms showed bands of 15 and 50 KDa by using SDS-PAGE. B. myersi venom chromatogram exhibited 16 peaks by RP-HPLC. We conclude that the composition of the three venoms is quite similar, being phospholipase A2 the common protein therein, and together with metalloproteinases they were the most abundant protein families in the venom of B. myersi. SDS-PAGE and RP-HPLC techniques allow a first approach to the profile of the venoms, which in turn could clarify the clinical syndrome produced.

RESUMEN Los venenos de las serpientes comprenden una mezcla compleja de proteínas, y existe una alta variabilidad interespecífica e intra-específica en su composición, incluso en la misma región. Nuestro objetivo fue comparar la composición de los venenos de Bothrocophias myersi, Crotalus durissus y Bothrops asper de la región andina de Colombia, mediante cromatografía líquida de alta eficiencia en fase reversa (RP-HPLC). Los venenos fueron entregados al grupo de investigación mediante un convenio con la Fundación Zoológica de Cali. El pool de venenos fue obtenido por extracción manual, liofilizado y congelado. La proteína de los venenos fue cuantificada por Absorbancia 280nm por medición directa con Nanodrop®. La composición proteica se estableció por RP-HPLC, utilizando una columna Lichosper 100 RP, C18 (250X4 mm) con un tamaño de poro de 5-jm, así como por electroforesis en gel dodecil sulfato de sodio-poliacrilamida (SDS-PAGE). La mayor cantidad de proteínas se encontró en el veneno de B. myersi (108.6 mg/mL), seguido de C. durissus (78.1 mg/mL) y B. asper (74.1 mg/mL). Todos los venenos mostraron bandas de 15 y 50 KDa por SDS-PAGE. El cromatograma de B. myersi exhibió 16 picos por RP-HPLC. Concluimos que la composición de los tres venenos es bastante similar, siendo la fosfolipasa A2 la proteína común en estos y junto con las metaloproteinasas fueron las familias de proteínas más abundantes en el veneno de B. myersi. Las técnicas de SDS-PAGE y el RP-HPLC permiten un primer acercamiento al perfil de los venenos, lo que a su vez podría contribuir a esclarecer el síndrome clínico producido.

Association of DEAR1 Tagging Single Nucleotide Polymorphisms With Breast Cancer in a Sample of Colombian Population: A Case Control Study.

PURPOSE: Ubiquitin ligase genes can act as oncogenes or tumor suppressor genes. They play a role in various diseases, including development and progression of breast cancer; the objective of this study was to evaluate the association of common variants in the ductal-epithelium-associated RING chromosome 1 (DEAR1) gene with breast cancer risk in a sample of Colombian population. METHODS: We carried out a case-control study to investigate associations of variants in DEAR1 with breast cancer in women from Colombia. Single nucleotide polymorphisms (SNPs) rs584298, rs2927970, rs59983645, and rs599167 were genotyped in 1022 breast cancer cases and 1023 healthy controls using the iPLEX® and Kompetitive Allele Specific PCR (polymerase chain reaction) (KASP) method. The associations between SNPs and breast cancer were examined by conditional logistic regression. The associations between SNPs and epidemiological/histopathological variables were examined by multinomial logistic regression. RESULTS: Associations were found between tag SNPs and breast cancer adjusted for the epidemiological risk factors rs584298 genotypes AG and GG (P = .048 and P = .004, respectively). The analysis of the disease characteristics showed that SNP rs584298 (genotype AG) (P = .015) shows association with progesterone receptor (PR) status and (genotype AA) (P = .048) shows association with human epidermal growth factor receptor 2 (HER2) status. CONCLUSIONS: The SNP rs584298 in DEAR1 showed associations with breast cancer and the expression of HER2 receptor; when this receptor is amplified, the result is aggressive tumoral subtype and expression of PR receptor that is associated with high-proliferative tumor grade. Validation of this SNP is important to establish whether this variant or the tagged variant is the cause for the risk association showed.

Soft Palate Modification Using a Collagen Crosslinking Reagent for Equine Dorsal Displacement of the Soft Palate and Other Upper Airway Breathing Disorders.

The mechanical properties of the soft palate can be associated with breathing abnormalities. Dorsal displacement of the soft palate (DDSP) is a naturally occurring equine soft palate disorder caused by displacement of the caudal edge of the soft palate. Snoring and a more serious, sometimes life-threatening, condition called obstructive sleep apnea (OSA) are forms of sleep-related breathing disorders in humans which may involve the soft palate. The goal of this study was to investigate the effect of injecting the protein crosslinker genipin into the soft palate to modify its mechanical properties for the treatment of equine DDSP with potential implications for the treatment of snoring and OSA in humans. Ex vivo experiments consisted of mechanical testing and a wind tunnel study to examine the effect of genipin on the mechanical properties, displacement, and vibration of equine soft palates. A pilot in vivo study was completed using DDSP and control horses to test the safety and effectiveness of injecting a genipin reagent into the soft palate. The wind tunnel testing demonstrated a greater than 50% decrease in transient deformation and a greater than 33% decrease in steady-state vibrations for all doses of genipin tested. Ultimate tensile stress, yield stress, and Young's modulus were higher in the genipin-treated distal soft palate specimens by 52%, 53%, and 63%, respectively. The pilot in vivo study showed a reduction of snoring loudness in all DDSP horses and elimination of DDSP in at least one of three horses. The difficulty of using a 1-meter-long endoscopic injection needle contributed to a consistent overinjection of the equine soft palates, causing excessive stretching (pillowing) and related degradation of the tissue. These ex vivo and in vivo results demonstrated reduced vibration amplitude and flaccidity and increased strength of genipin-treated soft palates, suggesting that genipin crosslinking could become an effective and safe treatment for soft palate related breathing abnormalities.

Evaluation of the effect of onlay mesenteric flaps on end-to-end jejunojejunostomy healing in horses.

OBJECTIVE: To evaluate the effect of onlay mesenteric flaps (MFs) with end-to-end jejunojejunostomy on stomal diameter, length of jejunum with reduced stomal diameter, abdominal adhesion formation, and healing. STUDY DESIGN: Experimental study. ANIMALS: Healthy adult horses (n = 6). METHODS: Two hand sewn end-to-end jejunal anastomoses using a 1 layer simple continuous serosubmucosal suture pattern were performed in each horse ∼ 2 and 5 m oral to the ileocecal fold. Using a random design for selection anastomosis location (oral or aboral), 1 anastomosis was covered with 2 adjacent onlay MFs secured with interrupted sutures and cyanoacrylate glue. Two weeks later, adhesion formation, stomal diameter, length of reduced jejunal stomal diameter, and healing were evaluated. RESULTS: Use of onlay MFs decreased stomal diameter (P = .05), increased length of reduced peristomal jejunal diameter (P = .05), surgical time (P = .003), and serosal fibrosis (P = .05). No difference was evident for adhesion formation, and degree of inflammation between techniques. CONCLUSION: End-to-end jejunojejunostomy covered with 2 onlay MFs is not recommended because this technique results in luminal reduction.

EVALUACIÓN DE LA ACTIVIDAD CITOTÓXICA Y ANTIMICROBIANA DEL COMPUESTO [Ag(phen)2]salH) / EVALUATION OF THE CITOTOXICITY AND ANTIMICROBIAL ACTIVITY OF THE [Ag(phen)2]salH COMPOUND / AVALIAÇÂO DA ACTIVIDADE CITOTÓXICA E ANTIMICROBIANA DO COMPOSTO [Ag(phen)2]salH

En este artículo se evaluó la actividad antimicrobiana y citotóxica de un nuevo complejo de plata(I) con el ión salicilato y 1,10-fenantrolina. La caracterización de este compuesto se realizó por espectroscopia de resonancia magnética nuclear de protón y carbono-13 (RMN ¹H y 13C), espectroscopia de absorción en la región de infrarrojo (IR), análisis térmico (TG/DSC) y análisis elemental (CHN). Los resultados obtenidos a través de estos métodos sugieren la formación del compuesto con fórmula empírica [Ag(phen)2] salH. Cuando fue comparada la actividad antimicrobiana y citotóxica de este complejo con otros compuestos de plata(I) y cobre(II) de actividad conocida, se observó que el ligante 1,10-fenantrolina incrementa estas propiedades. El compuesto en estudio, presenta la mayor inhibición del crecimiento bacteriano, los microorganismos Gram positivos fueron los más susceptibles. La actividad citotóxica fue evaluada en un panel de cinco líneas celulares tumorales humanas: MDA-MB231, PC-3, HT-29, HEp-2 y A549. A las concentraciones evaluadas, el compuesto produjo una respuesta citotóxica dosis-dependiente en todas las líneas celulares tumorales, particularmente para las líneas tumorales HT-29, MDA-MB231 y A549. Todo esto, sugiere su gran potencial para usos quimioterapéuticos.

This article evaluated the antimicrobial and cytotoxic activity of a new complex of silver(I) with the salicylate ion and 1,10-phenanthroline. The characteriza-tion of this compounds was performed by nuclear magnetic resonance spectroscopy of proton and carbon-13 (RMN ¹H y 13C), spectroscopy absorption in the infrared (IR), thermal analysis (TG/DCS) and elemental analysis (CHN). The results ob-tained through these methods suggest the formation of the compound with empiri-cal formula Ag(phen)2]salH 4. When was compared the antimicrobial activity and cytotoxicity of the complex with other compounds of silver(I) and copper(II) of known activity, we observed that 1, 10-phenalthroline ligand increases these properties. The compound under study has the highest inhibition of bacterial growth, Gram-positive microorganisms were the most susceptible. The cytotoxic activity was tested against a panel of fve human cancer cell lines: MDA-MB231, PC-3, HT-29, HEp-2 and A549. At the concentrations tested, the compound pro-duced a dose-dependent cytotoxic res-ponse against all tumor cell lines, parti-cularly against the HT-29, MDA-MB231 and A549 cell lines. All this suggests its potential chemotherapeutic use.

Neste artigo avaliou-se a atividade antimicrobiana e citotóxica de um novo complexo de prata(I) com o íon sali-cilato e 1,10-fenantrolina. A caracterização deste composto foi realizada por espectroscopia de ressonância magnética nuclear de próton e carbono-13 (RMN ¹H e 13C), espectroscopia de absorção na região de infravermelho (IV), análise térmico (TG/DSC), análi-se elementar (CHN). Os resultados ob-tidos através destes métodos sugerem a formação do composto com fórmula empírica [Ag(phen)2]salH. Quando foi comparada a atividade antimicrobiana e citotóxica deste complexo com outros compostos de prata(I) e cobre(II) de ati-vidade conhecida, observou-se que o ligante 1,10-fenantrolina aumenta essas propriedades. O composto em estudo apresenta maior inibição do crescimento bacteriano, os microorganismos Gram-positivos foram os mais suscetíveis. A atividade citotóxica foi avaliada em um painel de cinco linhas de células tu-morais humanas: MDA-MB231, PC-3, HT-29, HEp-2 e A549. Com as concen-trações avaliadas, o composto deu uma resposta citotóxica dose-dependência em todas as linhagens de células tumo-rais, particularmente para as linhas de células tumorais HT-29, MDA-MB231 e A549. Tudo isso, sugere, um grande potencial para aplicações em quimioterapia.

Implementación de estrategias in vitro para evaluar la funcionalidad de un suero fetal bovino colombiano / Implementation of in vitro strategies to evaluate the functionality of a Colombian fetal bovine serum

En este trabajo se presentan los resultados de las pruebas biológicas realizadas para evaluar la funcionalidad y desempeño del suero fetal bovino de fabricación nacional sobre el crecimiento de cultivos celulares con diversos requerimientos nutricionales. Realizando ensayos de eficiencia de clonaje, eficiencia de plaqueo y curvas de crecimiento sobre líneas celulares y fibroblastos, se demostró que el suero de fabricación nacional puede ser empleado en el cultivo continuo de las líneas A549, PC-3, HT-29, MDA-MB231 con un buen desempeño; y en fibroblastos, las células LSPG8G, MDBK e hibridomas puede ser usado siempre y cuando se emplee al 10% y se realicen cambios de medio al menos cada 48 horas. En ninguno de los ensayos se observó un efecto tóxico o adverso sobre el crecimiento de las células empleadas, aunque en algunos casos se observó una menor funcionalidad frente al crecimiento celular comparando los resultados con otros sueros calificados. Los resultados obtenidos destacan la utilidad del SFB nacional en la aplicación para la propagación de células poco exigentes en ensayos de corta duración, así como en procedimientos transitorios tales como la inactivación de la actividad enzimática de la tripsina y criopreservación.

In this work, we present the results of biological tests performed to evaluate the functionality and performance of fetal bovine serum produced in Colombia, on the growth of cell cultures with different nutritional requirements. Performing cloning efficiency tests, plating efficiency and growth curves of cell lines and fibroblasts, showed that the Colombian serum can be used with a good performance, in continuous culture of cell lines A549, PC-3, HT-29, MDA-MB231, in fibroblasts LSPG8G cells, MDBK and hybridomes can be used in a minimum concentration of 10% and medium every 48 hours. It should be noted that none of the treatments showed a toxic or adverse effect on the growth of the cells used, although in some cases had less functionality compared to cell growth by comparing the results with other qualified serum. Therefore, the Colombian showed to be suitable for the propagation of short-term culture cells, as well as transitional procedures such as trypsin inactivation, and cryopreservation.

Highly Sensitive Detection and Genotyping of HPV by PCR Multiplex and Luminex Technology in a Cohort of Colombian Women with Abnormal Cytology.

Cancer of the uterine cervix (CC) is the second most common cancer in women worldwide. In Colombia, CC is the second most frequent cancer among the entire women population and the first among women aged between 15 and 44 years, with an estimated incidence of 24.9 cases/100,000 inhabitants. The main risk factor is infection with one or more high-risk human papillomavirus (HPV) types. The aim of this study was to estimate the genotype-specific prevalence of human papillomavirus (HPV) DNA in patients with cervical pathology using the multiplex PCR and Luminex xMAP technology. In addition, we compared genotyping with Luminex xMAP and with Reverse Line Blot (RLB). A cohort of 160 patients participated in the study, of which 25.6% had no cervical lesions, 35% presented cervical intraepithelial neoplasia of grade I (CIN I), 10% CIN II, 20.6% CIN III and 8.8% CC. The most frequent viral types in all lesion grades were HPV16 and HPV18. Infections by a unique virus were less frequent (19.4%) than multiple infections (80.6%). Single infections were found in 22% of women with no cervical lesions, and in 14.3% of CIN I, 18.7% CIN II, 21.2% CIN III and 28.6% of CC. Multiple infections were observed in 78.0% of cervical samples with negative histopathologic diagnosis, and in 85.7% of CIN I, 81.2% CIN II, 78.8% CIN III and 71.4% CC. All samples analyzed with Luminex xMAP were HPV-positive, while we could detect HPV in only 48.8% of cases with RLB. Of the samples positive by both methods, there was a 67.2% correlation in the viral type(s) detected. In conclusion, Luminex suspension array showed a remarkably higher sensitivity compared with RLB. Multiple infections were unexpectedly common, being HPV types 16 and 18 the most prevalent in all histopathologic grades.

Detection of gene amplification in MYCN, C-MYC, MYCL1, ERBB2, EGFR, AKT2, and human papilloma virus in samples from cervical smear normal cytology, intraepithelial cervical neoplasia (CIN I, II, III), and cervical cancer / Detección de amplificación en los genes MYCN, C-MYC, MYCL1, ERBB2, EGFR y AKT2 y del virus de papiloma humano en muestras de cepillado cervical en mujeres con citología normal y con neoplasia intraepitelial cervical (NIC) I, II, III y cáncer de cuello uterino

Introduction: Cervical cancer is the second most common cancer among women worldwide and the second cause of cancer mortality in women. It has been demonstrated that the process of cervical carcinogenesis displays genetic and environmental epigenetic components. Currently, research is focused on new prognosis markers like oncogene amplification.Objectives: To perform detection of MYCN, C-MYC, MYCL1, ERBB2, EGFR, and AKT2 amplification. Additionally, to detect human papillomavirus in samples from normal cytology smear, cervical intraepithelial neoplasia (CIN) I, II, and III and cervical cancer patients.Methods: Papillomavirus (HPV) genotyping by reverse line blot (RLB) performed and gene amplification by detection with real-time PCR with Taqman probes.Results: HPV was present in 4% of the patients with normal cytology, 48% in CIN I, 63.6% in CIN II, 64% in CIN III, and 70.8% in cervical cancer. Genes amplified in cervical cancer were MYCN (39.1%), ERBB2 (34.7%), and MYCL1 (30.4%); showed higher amplification in high-grade lesions and cervical cancer in relation to low-grade lesions and normal cytology with statistically significant differences. Besides the genes, C-MYC, EGFR, and AKT2 were amplified in samples from patients with cervical cancer by 12%, 18%, and 13%, respectively; we did not find statistical differences.Conclusion: Higher prevalence of gene amplification and HPV was found in high-grade cervical lesions and cervical cancer.

Introducción: El cáncer cervical es el segundo cáncer más importante en mujeres a nivel mundial y es la segunda causa de muerte por cáncer en mujeres. Se ha demostrado que el proceso de carcinogénesis cervical presenta componentes tanto genéticos como epigenéticos y medio ambientales. En la actualidad, hay gran interés en la búsqueda de marcadores moleculares asociados con la progresión de esta enfermedad, uno de los posibles mecanismos y que además está poco estudiado en cáncer cervical es la amplificación génica de algunos oncogenes como la familia MYC, EGFR y AKT entre otros.Objetivos: Detectar la amplificación génica de MYCN, C-MYC, MYCL1, ERBB2, EGFR y AKT2 además de la presencia del virus de papiloma humano en cepillados cervicales en mujeres con citología normal o con neoplasia intraepitelial cervical (NIC) I, II y III o con cáncer cervical.Métodos: Se genotipificó mediante reverse line blot (RLB) el virus de papiloma humano (VPH) y se determinó el estado de amplificación génica de los genes mencionados mediante PCR en tiempo real utilizando sondas taqman.Resultados: El VPH se encontró presente en 4% de las pacientes con citología normal, en 48% en NIC I, 63.6% en NIC II, 64% en NIC III y 70.8% en cáncer cervical. Los genes MYCN, MYCL1 y ERBB2 mostraron mayor amplificación en lesiones de alto grado y cáncer con diferencias estadísticamente significativas a las lesiones de bajo grado y citología normal, en 39.1%, 34.7% y 30.4% respectivamente. Además, se encontraron amplificados los genes C-MYC, EGFR y AKT2, en muestras de pacientes con cáncer cervical, en 12%, 18% y 13% respectivamente. Sin embargo, no se observaron diferencias estadísticamente significativas con respecto a las lesiones de alto y bajo grado y citología normal.Conclusión: En las lesiones de alto grado como en cáncer cervical, se encuentra mayor prevalencia del virus al igual que se detectan mayor cantidad de alteraciones genéticas como la amplificación génica.

Efectos del uso del factor estimulante de colonias granulocíticas en la obtención de células madre en un grupo de pacientes con enfermedad arterial oclusiva crónica / Effects of the use of granulocyte colony stimulating factor for obtaining stem cells in a group of patients with chronic occlusive arterial disease

Es importante evaluar el perfil del uso del factor estimulante de colonias granulocíticas (fec-g) en pacientes con enfermedad arterial oclusiva crónica (eaoc), mediante el análisis de aspectos como eficacia y seguridad. Se examinaron los datos obtenidos de la cohorte de pacientes con eaoc que asistían regularmente a la clínica de Cirugía Vascular del Hospital Militar Central en Bogotá. El protocolo de movilización de células CD34+ hacia sangre periférica consistió en el uso de FEC-Grh a dosis de 600 mg/día por vía subcutánea (Filgrastim fec-g 300 mg Roche®), repartido en dos dosis diarias, en forma continua durante cinco días. Al realizar la comparación de valores a partir de hemogramas realizados antes y después de la movilización, se demostró incremento significativo en el número de leucocitos así como en la proporción de neutrófilos y basófilos; mientras que las proporciones de monocitos, eosinófilos y linfocitos disminuyeron significativamente. Con respecto al comportamiento de las células CD34+, no se muestra una diferencia significativa en el comportamiento del CD34+ con la edad, así como tampoco con el índice de masa corporal (imc). En lo relacionado con el peso y los niveles de CD34+, se observó que los pacientes que lograron una buena respuesta tenían un peso de 59,7 kg, mientras que los pacientes con regular respuesta, 68,1 kg.

The analyzed aspects such as efficacy and safety are important in the use of Granulocyte Colony Stimulating Factor in patients with chronic occlusive arterial disease were analyzed data from the cohort of patients with eaoc that regularly attended the Clinic for Vascular Surgery of the Hospital Militar Central in Bogotá. The protocol for CD34+ cell mobilization into peripheral blood involved the use of FEC-Grh at a dose of 600 mg/day administered subcutaneously (Filgrastim g-csf 300 mg Roche®) divided into two daily doses, continuously for five days. By comparing the values from blood counts performed before and after mobilization showed increased significant number of leukocytes as well as proportion of neutrophils and basophiles, whereas proportions of monocytes, eosinophils and lymphocytes decreased significantly. About the CD34+ cell behavior, it’s not shown significant difference between the behaviors of CD34+ with age, neither the imc. The analyzed done on the weight and CD34+ levels was observed that patients achieved a good response with a weight of 59.7 kg while 68.1 kg patients with regular response.

Oncogene amplification as tumor marker in a group of Colombian lung cancer patients / Amplificación oncogénica como marcador tumoral en un grupo de pacientes con cáncer pulmonar

Introduction: In spite of recent treatment advances, lung cancer continues to be the first world cancer related death cause; its mortality associated occupied the fifth place in Colombia in 2004. Complete surgical resection is the therapeutic option with the greatest cure probability, however it results frequently ineffective given the current incapacity in Colombia to an early detection of the disease. This study reports the characterization of a group of 30 lung cancer patients regarding the gene dose (gene copy number) found at the loci corresponding to genes EGFR (erb B1), PIK3CA and C-myc in tumor samples, and compares the results with the dose found in adjacent lung from the same patients. Methods: The gene dose of EGFR (erbB1), PIK3CA, and C-myc were measured by real time PCR in matched tumor and normal lung tissue samples. Results are expressed as the multiplicity of each gene dose with respect to a single copy reference gene. In this case the gene HHB (human hemoglobin). Antiquity of the cases ranged from 5 to 10 years. Results: An increased gene dose for EGFR and PIK3CA was a feature clearly associated to the tumor phenotype of the sample (found in 96 and 100% of the tumors respectively). Quantitative measure of this feature demonstrated for both genes a high sensitivity and specificity for tumor/normal discrimination as confirmed by the ROC analysis. On the other hand, the Spearman test showed a great correlation between EGFR and PIK3CA doses (r=0.75). C-myc was the gene whose dose was less consistently correlated to the tumor phenotype, however most of the patients with amplified C-myc presented distant spread of tumor cells (metastasis) at diagnosis. Conclusion: Quantitative measurement of EGFR, PIK3CA, and C-myc gene dose by real time PCR provides a method for tumor phenotype recognition in DNA samples from lung tissue.

Introducción: A pesar de los avances terapéuticos actuales, el cáncer de pulmón sigue como la primera causa de muerte por cáncer en el mundo, ocupando Colombia el quinto lugar en mortalidad por este tipo de afección en el 2004. La resección quirúrgica total es la alternativa terapéutica con mayores probabilidades de curaciones, pero resulta poco efectiva en el país por la incapacidad actual para detectar tempranamente la enfermedad. Este trabajo informa la caracterización de un grupo de 30 pacientes con cáncer de pulmón con referencia a la dosis génica hallada en los loci correspondientes a los genes EGFR (erb B1), PIK3CA y C-myc en muestras tumorales, comparada con la dosis encontrada en el tejido normal adyacente de los mismos enfermos. Métodos: La dosis génica se midió en cada caso por PCR en tiempo real sobre ADN aislado de tejido tumoral y normal preservado en parafina de cada paciente. Los resultados se expresan como el número de veces que la dosis de cada gen sobrepasa la dosis de un gen de referencia, en este caso el HHB (hemoglobina humana b). El rango de antigüedad de los casos fue de 5 a 10 años. Resultados: Una dosis génica incrementada para los genes EGFR, PIK3CA demostró ser una característica claramente asociada con el fenotipo tumoral (96% y 100% de los tumores respectivamente). La medición cuantitativa de dicho fenómeno demostró en ambos casos gran sensibilidad y especificidad para la discriminación tumor/normal como lo confirma el análisis ROC. Por otro lado, la amplificación simultánea de ambos genes en el mismo paciente fue un hecho observado con alta frecuencia (Spearman=0.75). La dosis de C-myc mostró una asociación menos consistente con el carácter tumoral, sin embargo todos los pacientes con C-myc amplificado presentaron dispersión distante de células tumorales (metástasis).

Cytotoxicity of withanolides isolated from Acnistus arborescens.

A new withanolide identified by spectroscopic analysis as 12beta-acetoxy-4-deoxy-5,6-deoxy-Delta(5)-withanolide D and Withanolide D, were isolated from the leaves of Acnistus arborescens. Cytotoxic activity of these two compounds against human tumor cell lines HT-29, MCF-7, MKN-45, HEp-2, HeLa, U-937 and two human normal fibroblast cultures, Fib04 and Fib05, were assessed. Withanolide D presented in vitro cytotoxic activity against tumor cell lines at the low micromolar range (LC(50):1.0 to 1.69 microM) and showed a slightly lower activity against Fib04, suggesting moderated selectivity among tumoral and normal cells. No cytotoxic effect was observed for 12beta-acetoxy-4-deoxy-5,6-deoxy-Delta(5)-withanolide D.

Análisis AFLP de variación somaclonal en embriones somáticos de Hevea brasiliensis / AFLP analysis of somaclonal variation in Hevea brasiliensis somatic embryos

La variación somaclonal es un evento que puede aparecer durante el cultivo "in vitro" de tejidos vegetales, son modificaciones genéticas en las células y los tejidos cultivados. Esta variación ha sido usada en procesos de mejoramiento genético y para ampliar la variación genética natural; sin embargo, cuando el objetivo es la propagación clonal de una variedad, como en el caso de la micropropagación del árbol del caucho (Hevea brasiliensis) mediante embriogénesis somática, la variación somaclonal resulta un fenómeno poco deseado. Este trabajo estableció una metodología para la detección de variación somaclonal en embriones somáticos de Hevea brasiliensis de los clones IAN 710 e IAN 873 y plantas donadoras de hojas para el proceso de embriogénesis somática, por medio de marcadores moleculares tipo AFLPs. Esta técnica robusta y confiable permitió evidenciar variación entre plantas donadoras, y una alta tasa de variación somaclonal entre callos embriogénicos de Hevea brasiliensis, de igual manera entre callos embriogénicos y plantas donadoras