Search

To evaluate the impact of immunoprophylaxis with palivizumab in preterm infants less than 35 weeks in terms of hospitalization rate, intensive care unit requirement, and mortality.A prospective cohort study was conducted at six Colombian hospitals. Preterm infants less than 35 weeks who received at least one dose of palivizumab during the first 6 months of life were included. The primary outcome was the hospitalization rate related to respiratory syncytial virus (RSV) infection.A total of 222 newborns participated in the study; 204 (91.8%) completed the 6-month follow-up, and three died during the study. 88.7% received a second dose of palivizumab, 79.7% a third, 34.7% a fourth, and 25.2% a fifth. The nonadjusted incidence rate of RSV infection was 2.4%, and the overall RSV-positive hospitalization rate was 1.9%. The proportion of patients that required Neonatal Intensive Care Unit (NICU) and mechanical ventilation in relation to RSV infection was 1.4%. Discharge with home oxygen, pulmonary dysplasia, and being younger than 6 months were significantly associated with respiratory infection. Furthermore, exposition to cigarette smoke was the only factor associated with increased risk of hospitalization. The group that required hospitalization received fewer doses of palivizumab (p = 0.049). No discontinuation of treatment due to adverse events were reported. No death was judged to be related to palivizumab.The hospitalization rate and the need for NICU admission were lower than those reported in the literature. In this real-life setting, palivizumab appears to be effective in preventing serious cases of RSV infection.

La obesidad es un problema del país, que repercute en mujeres embarazadas ante el cual existe carencia de datos estadísticos en nuestro país. Se la define como una acumulación excesiva de grasa que puede ser perjudicial para la salud. Puede ser valorada mediante el IMC que es el resultado del peso de una persona en kilogramos dividido por el cuadrado de la talla en metros; Así una persona con IMC mayor a 25 es considerada sobrepeso, mientras que un valor mayor a 30 es obesidad, estado que genera riesgo para padecer diabetes, enfermedad cardiovascular o cáncer. Objetivo: Identificar los cambios metabólicos que se producen en una madre con sobrepeso u obesidad, puntualizar los factores de riesgo metabólicos que predispone esta condición y aportar conocimientos científicos sobre esta condición metabólica de riesgo materno-fetal. Metodología: Se busca realizar un estudio observacional, transversal, analítico La población consistió en mujeres embarazadas en una población al sur de Quito, en el centro de Salud de Chimbacalle. Tras aplicar criterios de inclusión y exclusión se obtuvo una muestra de 65 embarazadas, con edades comprendidas entre los 19-30 años. Resultados: De los resultados obtenidos, destacan, que un 61,54% de las embarazadas presentaron sobrepeso u obesidad. En relación a los componentes del síndrome metabólico, la circunferencia abdominal elevada y dislipidemia son las más frecuentes. Se encontró una prevalencia del 13,85% de síndrome metabólico y se observó que embarazadas con obesidad o sobrepeso en etapas tempranas del embarazo, generan un estado de mayor riesgo para presentar, aumento de circunferencia abdominal, así como dislipidemia, con un RP 3,5 para hipertrigliceridemia. También se encontró un RP de 0.61 para Hipertensión Arterial. No se encontró relación con glicemia elevada. Conclusiones: En la muestra estudiada, las embarazadas con sobrepeso u obesidad presentan un mayor riesgo para dislipidemia y una circunferencia abdominal elevada.

Antecedentes: Se desarrolló un método diagnóstico fractal para evaluar células del cuello uterino utilizando el concepto de Armonía Matemática Intrínseca (AMI) y variabilidad celular, el cual diferencia matemáticamente células normales de células L-SIL y H-SIL, haciendo innecesario el diagnóstico de células ASCUS.Objetivo: confirmar la capacidad diagnóstica de la metodología desarrollada mediante un estudio ciego de comparación con el Gold StandardMétodos: se tomaron fotografías digitales de 50 preparaciones citológicas de mujeres entre 20 y 55 años: 5 con diagnóstico de citología normal y 45 con diferentes grados de lesión hasta carcinoma, incluyendo 5 ASCUS. Se calculó la dimensión fractal de tres objetos matemáticos: núcleo, citoplasma y totalidad, a partir de la superposición de cinco rejillas. Además se evaluó su dimensión fractal mediante el concepto de AMI y variabilidad celular. Los resultados obtenidos se compararon con el diagnóstico citopatológico convencional determinando su sensibilidad, especificidad y coeficiente kappa.Resultados: La sensibilidad y especificidad fue del 100%, y el coeficiente Kappa de 1.Conclusiones: Los resultados en una población diferente a la inicial son una evidencia de la capacidad de esta metodología para diagnosticar objetiva y cuantitativamente células normales, L-SIL y H-SIL, así como aclarar el diagnóstico de las células ASCUS con base en la dimensión fractal y el concepto de AMI y variabilidad.

Describe the natural history of anal HPV among men.Prospective study among men 18-70 years (n=665), from Cuernavaca, Mexico who completed questionnaires and provided specimens (HPV genotyped) at enrollment and 1+ follow-up visit. HPV prevalence and incidence were estimated. Prevalence ratios were calculated with Poisson regression using robust variance estimation. Person-time for incident HPV infection was estimated using number of events modeled as Poisson variable for total person-months.Anal infection prevalence: any HPV type=15%, high-risk=8.4%, HPV16=1.4%, tetravalent vaccine types (4vHPV)=4.4%, nonavalent vaccine types (9vHPV)=6.3%. Factors associated with prevalence: 50+ lifetime female sex partners (adjusted prevalence ratio, a PR=3.25, 95% CI:1.12- 9.47), 10+ lifetime male sex partners (aPR=3.06, 95%CI:1.4- 6.68), and 1+ recent male anal sex partners (aPR=2.28, 95%CI:1.15-4.5). Anal incidence rate: high-risk HPV=7.8/1000 person-months (95%CI:6.0-10.1), HPV16=1.8/1000 personmonths (95%CI:1.1-2.9),4vHPV=3.4/1000 person-months (95%CI:2.3-4.9) and 9vHPV=5.5/1000 person-months (95%CI:4.1-7.5).Implementation of universal HPV vaccination programs, including men, is a public health priority.Generar evidencia que apoye la vacunación universal contra VPH.Estudio prospectivo con hombres 18-70 años (n=665) de Cuernavaca, México con cuestionarios y genotipificación de VPH en muestras (2+mediciones). Se estimó prevalencia e incidencia; se calcularon tasas de prevalencia con regresión Poisson. Se estimó persona-tiempo para infecciones incidentes.Prevalencia de infección anal: cualquier tipo de VPH=15%, altoriesgo=8.4%, VPH16=1.4%, tipos en vacuna tetravalente=4.4% y tipos en vacuna nonavalente=6.3%. Factores asociados con infección prevalente: 50+ parejas sexuales femeninas en la vida (tasa de prevalencia ajustada, TPa=3.25, IC95%:1.12-9.47); 10+ parejas sexuales masculinas en la vida (TPa=3.06, IC95%:1.4- 6.68) y 1+ parejas masculinas (sexo anal) recientes (TPa=2.28, IC95%:1.15-4.5). Tasas de incidencia para infección anal: VPH alto-riesgo=7.8/1000 persona-meses (IC95%:6.0-10.1), VPH 16=1.8/1000 persona-meses (95%IC:1.1-2.9), tipos en vacuna tetravalente=3.4/1000 persona-meses y tipos en vacuna nonavalente=5.5/1000 persona-meses.mplementación de programas de vacunación universal (incluyendo hombres) contra VPH es una prioridad en salud pública.

To determine external genital lesion (EGL) incidence -condyloma and penile intraepithelial neoplasia (PeIN)- and genital HPV-genotype progression to these EGLs.Participants (healthy males 18- 74y from Cuernavaca, Mexico, recruited 2005-2009, n=954) underwent a questionnaire, anogenital examination, and sample collection every six months;including excision biopsy on suspicious EGL with histological confirmation.Linear array assay PCR characterized 37 high/low-risk HPV-DNA types. EGL incidence and cumulative incidence were calculated, the latter with Kaplan-Meier.EGL incidence was 1.84 (95%CI=1.42-2.39) per 100-person-years (py); 2.9% (95%CI=1.9-4.2) 12-month cumulative EGL.Highest EGL inci- dence was found in men 18-30 years:1.99 (95%CI=1.22-3.25) per 100py. Seven subjects had PeIN I-III (four with HPV16). HPV11 most commonly progresses to condyloma (6-month cumulative incidence=44.4%, 95%CI=14.3-137.8). Subject with high-risk sexual behavior had higher EGL incidence.In Mexico, anogenital HPV infection in men is high and can cause condyloma. Estimation of EGL magnitude and associated healthcare costs is necessary to assess the need for male anti-HPV vaccination.Determinar incidencia de lesiones genitales externas (LGE) –condiloma y neoplasia intraepitelial del pene (NIP)– y progresión de genotipos deVPH a LGE.Se aplicaron cuestionarios,examen anogenital y recolección de muestras cada seis meses a hombres sanos (18-74 años, de Cuernavaca, México, reclutados 2005-2009, n=954) con biopsia y confirmación histológica. Se caracteri- zaron 37 tipos de ADN-VPH; se calculó incidencia de LGE (cumulativa con Kaplan-Meier).Incidencia de LGE=1.84 (IC95%=1.42-2.39) por 100-persona-años (pa); 2.9% (IC95%=1.9-4.2) LGE acumulativa a 12 meses. Mayor incidencia de LGE entre hombres 18-30 años; 1.99 (IC95%=1.22-3.25) por 100pa.Siete sujetos tuvieron NIP I-III. VPH-11 más comúnmente progresa a condiloma (incidencia acumulativa a seis meses=44.4%, IC95%=14.3-137.8). Los sujetos con comportamiento sexual de alto riesgo tuvieron mayor incidencia de LGE.En México la infección anogenital conVPH es alta y puede causar condiloma. La estimación de magnitud de LGE y los costos sanitarios asociados se necesita para evaluar la necesidad de vacunación contra VPH en hombres.

Objetivo Determinar la carga de la enfermedad por cancer en Santander a traves de los anos de vida ajustados por discapacidad (AVISA). Metodos Estudio descriptivo de carga de la enfermedad para determinar los AVISA producidos por Cancer en Santander. La unidad de analisis fueron los registros del Observatorio Poblacional de Cancer de la Universidad Autonoma de Bucaramanga y el registro de mortalidad del Departamento Administrativo Nacional de Estadisticas del ano 2005. Resultados La carga global de enfermedad para Santander se estimo en 877 AVISA totales por cada cien mil personas, de los cuales 50 eran debido a discapacidad y 827 a muerte prematura. Se evidencia que los AVISA por muerte prematura superan ampliamente a los AVISA por discapacidad, 94 % versus 6 % respectivamente. En hombres los mayores valores de AVISAS por muerte prematura fueron estomago (169,8), leucemias (106,8), colon y recto (100,4), linfomas y mielomas multiples (89,9). Mientras que en las mujeres los mayores valores se observaron en cervico uterino (122,4), mama (121,9), estomago (94,2) y leucemias (86,0). Los tipos y las localizaciones de cancer con mas AVD fueron: colon y recto (11,3), mama (6,2), higado (6,05) y cervico uterino (5,43). Conclusiones La carga de enfermedad por cancer en Santander durante el ano 2005 se debe principalmentea los anos de vida perdidos por muerte prematura en ambos sexos y para todoslos grupos de edades.

Objective To analyze the role of Human Papillomavirus (HPV) and other risk factors in the regression of cervical lesions in women from the Bogota Cohort. Methods 200 HPV positive women with abnormal cytology were included for regression analysis. The time of lesion regression was modeled using methods for interval censored survival time data. Median duration of total follow-up was 9 years. Results 80 (40%) women were diagnosed with Atypical Squamous Cells of Undetermined Significance (ASCUS) or Atypical Glandular Cells of Undetermined Significance (AGUS) while 120 (60%) were diagnosed with Low Grade Squamous Intra-epithelial Lesions (LSIL). Globally, 40% of the lesions were still present at first year of follow up, while 1.5% was still present at 5 year check-up. The multivariate model showed similar regression rates for lesions in women with ASCUS/AGUS and women with LSIL (HR= 0.82, 95% CI 0.59–1.12). Women infected with HR HPV types and those with mixed infections had lower regression rates for lesions than did women infected with LR types (HR=0.526, 95% CI 0.33–0.84, for HR types and HR=0.378, 95% CI 0.20–0.69, for mixed infections). Furthermore, women over 30 years had a higher lesion regression rate than did women under 30 years (HR= 1.53, 95% CI 1.03–2.27). The study showed that the median time for lesion regression was 9 months while the median time for HPV clearance was 12 months. Conclusions In the studied population, the type of infection and the age of the women are critical factors for the regression of cervical lesions.

Better information on the prevalence of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infection is needed in many world areas.Cross-sectional study of population-based samples of nonpregnant women aged 15 to 44 years in Nigeria, Colombia, Argentina, Vietnam (2 areas), China, Thailand (2 areas), Korea, and Spain. 5,328 consenting women aged 15 to 44 years participated. Exfoliated cervical cells were collected and testing for CT and NG and human papillomavirus (HPV) was done using PCR-based assays.Age-standardized CT prevalence ranged between 0.2% (95% confidence interval, CI: 0.0-0.7%) in Spain and 5.6% (95% CI: 3.4-7.8%) in Nigeria. NG ranged between 0% (with broad CIs) in several areas and 2.6% (95% CI: 1.0-4.2%) in Nigeria. Prevalence of CT in all areas combined was greater in women aged 15 to 24 (4.5; 95% CI: 3.4-5.8%) than 25 to 44 (2.6; 95% CI: 2.1-3.1%), whereas NG prevalence was similar in the 2 age groups (0.3%). The only significant risk factors were NG infection (for CT), CT infection (for NG) and infection with high-risk HPV types (for both).The prevalence of CT and, most notably, NG was relatively low in a variety of countries. Our findings, however, do not apply to subsets of high-risk women who are likely to be underrepresented in our population-based samples.

La validez de los indicadores de exposición es una condición necesaria en epidemiología si se han de obtener resultados válidos en la medición de los riesgos asociados con la exposición a agentes nocivos en el entorno laboral. Sin embargo, llevar a cabo la validación de estos indicadores de exposiciones pasadas no es tarea fácil. Debido a la falta de mediciones de referencia en el ámbito de la higiene industrial y de concentraciones representativas de bioindicadores que reflejen las exposiciones pasadas, el método de los autoinformes se ha utilizado para recoger datos de exposición indirectos. No obstante, los datos acerca de agentes nocivos específicos son a menudo deficientes y deben completarse con otros sobre los factores condicionantes de la exposición. La validez de los autoinformes mejora cuando se utilizan listas de verificación e iconos ilustrativos, mientras que la calidad de la información sobre las exposiciones personales mejora cuando se incorporan datos secundarios acerca de las exposiciones y de los factores que las condicionan o determinan. La exposición se puede determinar mediante matrices de exposición, evaluación por expertos y modelos de exposición, integrando datos primarios y secundarios acerca de las exposiciones y sus factores condicionantes. Las matrices contienen datos agrupados y, por consiguiente, pueden llevar a errores a la hora de clasificar las exposiciones individuales e introducir sesgos en la estimación de los riesgos. La evaluación por expertos es probablemente el método con el índice de validez más alto, pero puede entrañar costos muy altos en el caso de estudios de cierta magnitud. Otra posibilidad con buenas perspectivas es la de utilizar un modelo formal para evaluar las exposiciones patentes y mejorarlo mediante la evaluación por expertos en situaciones en las cuales los resultados del modelo parezcan alejarse de la realidad.In epidemiology, it is necessary that exposure indicators have good validity in order to obtain valid results when measuring the risks associated with occupational exposure to environmental noxious agents. However, ensuring the validity of past exposure data is no easy task. Because there are no environmental hygiene measures or representative levels of bioindicators signaling past exposure, self-reports have been used as a source of indirect exposure data. Unfortunately, data on specific agents are commonly poor and need to be complemented with data on the determinants of exposure. The validity of self-reports improves when certain techniques, such as control lists and icons, are employed, and the quality of individual exposure data improves when secondary data on exposure and its conditioning or determining factors are incorporated. Exposure can be determined by means of exposure matrices, assessment by experts, and exposure models, and by using a combination of primary and secondary data on exposure and its conditioning factors. Matrices contain pooled data and can thus lead to errors in classifying individual exposure and to biased risk estimates. Assessment by experts is probably the method with the highest validity, but it can become expensive when studies are large. It is also feasible to use a formal model for assessing perceivable exposures, complemented with expert assessments whenever the results of the model appear to deviate from reality.

Originally known for its Fe-Cu skarn mineralization, the Andahuaylas-Yauri belt of southeastern Peru is rapidly emerging as an important porphyry copper province. Field work by the authors confirms that mineralization in the belt is spatially and temporally associated with the middle Eocene to early Oligocene (~48–32 Ma), calc-alkaline Andahuaylas-Yauri batholith, a composite body with an areal extent of ~300 × 130 km emplaced into clastic and carbonate strata (e.g., Yura Group and Ferrobamba Formation) of Jurassic to Cretaceous age. Batholith emplacement included early-stage, mafic, cumulate gabbro and diorite between ~48 and 43 Ma, followed by pulses of granodiorite and quartz monzodiorite at ~40 to 32 Ma. Coeval volcanic rocks make up the middle Eocene to early Oligocene Anta Formation, a sequence of >1,000 m of andesite lava flows and dacite pyroclastic flows with interbedded volcaniclastic conglomerate. Sedimentary rocks include the red beds of the Eocene to early Oligocene San Jeronimo Group and the postmineralization late Oligocene to Miocene Punacancha and Paruro formations. Eocene and Oligocene volcanic and sedimentary rocks are interpreted to have accumulated largely in both transtensional and contractional synorogenic basins. New and previously published K-Ar and Re-Os ages show that much of the porphyry-style alteration and mineralization along the belt took place during the middle Eocene to early Oligocene (~42–30 Ma). Thus, batholithic magma emplacement, volcanism, and sedimentation are inferred to have accompanied a period of intense deformation, crustal shortening, and regional surface uplift broadly synchronous with the Incaic orogeny. Supergene mineralization is inferred to have been active since the Pliocene on the basis of geomorphologic evidence and a single K-Ar determination (3.3 ± 0.2 Ma) on supergene alunite. The belt is defined by 31 systems with porphyry-style alteration and mineralization, including 19 systems grouped in 5 main clusters plus 12 separate centers, and by hundreds of occurrences of magnetite-rich, skarn-type Fe-Cu mineralization. Porphyry copper stocks are dominated by calc-alkaline, biotite- and amphibole-bearing intrusions of granodioritic composition, but monzogranitic, monzonitic, quartz-monzonitic, and monzodioritic stocks occur locally. Hydrothermal alteration includes sericite-clay-chlorite, and potassic, quartz-sericitic, and propylitic assemblages. Calcic-potassic and advanced argillic alteration associations are locally represented, and calc-silicate assemblages with skarn-type mineralization occur where carbonate country rocks predominate. Porphyry copper deposits and prospects of the belt range from gold-rich, molybdenum-poor examples (Cotabambas), through deposits carrying both gold and molybdenum (Tintaya, Los Chancas), to relatively molybdenum-rich, gold-poor end members (Lahuani). Gold-only porphyry systems are also represented (Morosayhuas). Gold-rich porphyry copper systems are rich in hydrothermal magnetite and display a positive correlation between Cu and Au in potassic alteration. The bulk of the hypogene Cu (-Au, -Mo) mineralization occurs in the form of chalcopyrite and bornite, in intimate association with early-stage potassic alteration which, in many deposits and prospects, is variably overprinted by copper-depleting sericite-clay-chlorite alteration. Most porphyry copper systems of the belt lack economically significant zones of supergene chalcocite enrichment. This is due primarily to their relatively low pyrite contents, the restricted development of quartz-sericitic alteration, and the high neutralization capacities of both potassic alteration zones and carbonate country rocks as well as geomorphologic factors. Leached cappings are irregular, typically goethitic, and contain copper oxide minerals developed by in situ oxidation of low-pyrite, chalcopyrite (-bornite) mineralization. Porphyry copper-bearing stocks emplaced in the clastic strata of the Yura Group and certain phases of the Andahuaylas-Yauri batholith may develop appreciable supergene chalcocite enrichment in structurally and lithologically favorable zones. A model for the region suggests that the calc-alkaline magmas of the Andahuaylas-Yauri batholith and subsequent porphyry-style mineralization were generated during an event of subduction flattening which triggered the crustal shortening, tectonism, and uplift assigned to the Incaic orogeny. Shortening of the upper crust would have impeded rapid magma ascent favoring storage of fluid in large chambers which, at the appropriate depth in the uppermost crust, would have promoted large-scale porphyry copper emplacement. Geodynamic reconstructions of the late Eocene to early Oligocene period of flat subduction in the central Andes suggest that emplacement of the Andahuaylas-Yauri batholith took place at an inflection corridor in the subduction zone broadly coincident with the position of the present-day Abancay deflection. Similarly, evidence from southeastern Peru suggests that the Andahuaylas-Yauri belt may be continuous with the late Eocene to early Oligocene porphyry copper belt of northern Chile and that the process of subduction flattening in southern Peru also may have taken place in northern Chile between ~45 and 35 Ma.

Little is known about the factors that influence clearance of human papillomavirus (HPV), the primary cause of cervical carcinoma. A total of 227 women cytologically normal and HPV positive at baseline were identified from a population-based cohort of 1,995 Bogota, Colombia, women aged 13-85 years followed between 1993 and 2000 (mean follow-up, 5.3 years). HPV DNA detection and viral load determination were based on a GP5+/GP6+ polymerase chain reaction enzyme immunoassay. Rate ratio estimates for HPV clearance were calculated by using methods for interval-censored survival time data. Analyses were based on 316 type-specific HPV infections. HPV 16 had a significantly lower clearance rate than infections with low-risk types (rate ratio (RR) = 0.47, 95% confidence interval (CI): 0.32, 0.72), HPV types related to HPV 16 (types 31, 33, 35, 52, 58) had intermediate clearance rates (RR = 0.62, 95% CI: 0.47, 0.94), and other high-risk types did not show evidence of slower clearance compared with low-risk types. Infections with single and multiple HPV types had similar clearance rates. There was no evidence of a dose-response relation between clearance and viral load. Observed was slower clearance in parous women (RR = 0.64, 95% CI: 0.47, 0.89) and faster clearance in ever users of oral contraceptives (RR = 1.38, 95% CI: 1.07, 1.77).

Low grade squamous intra-epithelial lesions could be considered as a manifestation of human papillomavirus exposition, however the discrepancy between rates of infection with human papillomavirus and development of low grade squamous intra-epithelial lesions is notable. Here we report a cross-sectional three-armed case–control study in the Colombian population, to compare the risk factors of women with low grade squamous intra-epithelial lesions with that of human papillomavirus DNA-negative and positive women with normal cytology. British Journal of Cancer (2002) 87, 1417–1421. doi:10.1038/sj.bjc.6600650 www.bjcancer.com © 2002 Cancer Research UK

Human papillomavirus is the principal risk factor associated with cervical cancer, the most common malignancy among women in Colombia. We conducted a survey, aiming to report type specific prevalence and determinants of human papillomavirus infection in women with normal cytology. A total of 1859 women from Bogota, Colombia were interviewed and tested for human papillomavirus using a general primer GP5+/GP6+ mediated PCR–EIA. The overall HPV DNA prevalence was 14.8%; 9% of the women were infected by high risk types, 3.1% by low risk types, 2.3% by both high risk/low risk types and 0.4% by uncharacterized types (human papillomavirus X). Thirty-two different human papillomavirus types were detected, being human papillomavirus 16, 58, 56, 81(CP8304) and 18 the most common types. The human papillomavirus prevalence was 26.1% among women younger than 20 years, 2.3% in women aged 45–54 years, and 13.2% in women aged 55 years or more. For low risk types the highest peak of prevalence was observed in women aged 55 years or more. Compared to women aged 35–44 years, women aged less than 20 years had a 10-fold increased risk of having multiple infections. Besides age, there was a positive association between the risk of human papillomavirus infection and number of regular sexual partners and oral contraceptive use. In women aged below 25 years, high educational level and having had casual sexual partners predicted infection risk. In conclusion, there was a broad diversity of human papillomavirus infections with high risk types being the most common types detected. In this population multiplicity of sexual partners and, among young women, high educational level and casual sexual partners seem to determine risk. British Journal of Cancer (2002) 87, 324–333. doi:10.1038/sj.bjc.6600442 www.bjcancer.com © 2002 Cancer Research UK

INTRODUCCION: La mujer en el climaterio presenta múltiples síntomas y signos como consecuencia del déficit estrogénico. Existen diversos medicamentos, esquemas y dosis utilizadas en la terapia hormonal de sustitución (THS). Se evalúa en el presente estudio la eficacia de dos diferentes esquemas terapéuticos combinados con estrógeno y gestágeno en mujeres perimenopáusicas.MATERIALES Y METODOS: Se diseñó un ensayo clínico controlado, multicéntrico, aleatorizado, abierto y comparativo entre dos combinaciones hormonales diferentes (estrógenos conjugados 0.625 mg/día más acetato de medroxiprogesterona 5 mg del día 11 al 21 –grupo A- y valerato de estradiol 2 mg/día por 21 días más acetato de ciproterona 1 mg del día 11 al 21, grupo B. Se reclutaron, entre abril de 1993 y diciembre de 1995, 104 mujeres voluntarias sanas, en perimenopausia y con presencia de oleadas de calor y otros síntomas secundarios al hipoestrogenismo. Se incluyen 87 mujeres que cumplen los requisitos para el presente análisis. Las pacientes fueron seguidas clínicamente durante un año, con controles al comienzo, al mes, tercer, sexto, noveno y doce meses de tratamiento. Se evaluaron las diferencias por grupo de tratamiento y en los diferentes tiempos. Para las variables cuantitativas se realizó el análisis de ANOVA y para las cualitativas el test de chi cuadrado o el de Fisher, usando como nivel de significancia una p

Determining the burden of cancer in Santander using disability adjusted life years (DALY).This was a descriptive study of the disease burden for determining DALYs caused by cancer in Santander. The unit of analysis consisted of the Autonomous University of Bucaramanga- Population-Based Cancer Centre records and National Bureau of Statistics- mortality records for 2005.The global burden of disease for Santander was estimated at 877 DALY per hundred thousand people, 50 being due to disability and 827 to premature death. It was seen that premature death DALY (94 %) greatly outweighed disability DALY (6 %). The highest DALY values due to premature death in men were related to cancer of the stomach (169.8), leukaemia (106.8), colon and the rectum (100.4), lymphomas and multiple myelomas (89.9), whilst the highest values in women were observed in cervical (122.4), breast (121.9) and stomach cancer (94.2) and leukaemia (86.0). The types and cancer sites related to more years of life lost (YLL) were the colon and rectum (11.3), breast (6.2), liver (6.05) and cervical cancer (5.43).The burden of disease from cancer in Santander in 2005 was mainly due to premature death YLL in both sexes and all age-groups.

A partir de la evaluación de las dimensiones fractales y aplicando el concepto de variabilidad y armonía matemática intrínseca celular (AMI), se desarrolló un método matemático de aplicación clínica para el diagnóstico de células preneoplásicas y neoplásicas del epitelio escamoso cervical, el cual supera el diagnóstico de ASCUS (células escamosas atípicas de significado no determinado). A partir de un método desarrollado previamente para el diagnóstico de células normales, ASCUS y L-SIL, se realizaron permutaciones estructurales fractales con los valores generales de la AMI y de variabilidad fractal para normalidad y enfermedad, buscando los prototipos generales de células normales, preneoplásicas y neoplásicas. Se midieron cinco células ASCUS y cinco cancerígenas del epitelio escamoso del cuello uterino y se encontró que para la normalidad hay 18 prototipos, mientras que para la anormalidad 44, incluyendo todos los estados de evolución hasta carcinoma.Estos resultados fueron confirmados al comparar los resultados obtenidos por las técnicas convencionales con los obtenidos por esta metodología; lo que hace pensar que se desarrolló una nueva metodología que permite diferenciar los distintos tipos de células del epitelio escamoso del cuello uterino (normales o cancerígenas).

High parity, early age at first full-term pregnancy (FTP), and long-term oral contraceptive (OC) use increase cervical cancer risk, but it is unclear whether these variables are also associated with increased risk of acquisition and persistence of human papillomavirus (HPV) infection, the main cause of cervical cancer. Information on reproductive and menstrual characteristics and OC use were collected from 14 areas worldwide, among population-based, age-stratified random samples of women aged 15 years or older. HPV testing was done using PCR-based enzyme immunoassay. Unconditional logistic regression was used to estimate the odds ratios (OR) of being HPV-positive according to reproductive and menstrual factors and corresponding 95% confidence intervals (CI). When more than two groups were compared, floating CIs (FCI) were estimated. A total of 15,145 women (mean age, 40.9 years) were analyzed. Women with ≥5 FTPs (OR, 0.90; 95% FCI, 0.76-1.06) showed a similar risk of being HPV-positive compared with women with only one FTP (OR, 1.00; 95% FCI, 0.86-1.16). However, nulliparous women showed an OR of 1.40 (95% CI, 1.16-1.69) compared with parous women. Early age at first FTP was not significantly related to HPV positivity. HPV positivity was similar for women who reported ≥10 years of use of OCs (OR, 1.16; 95% FCI, 0.85-1.58) and never users of OCs (OR, 1.00; 95% FCI, 0.90-1.12). Our study suggests, therefore, that high parity, early age at first FTP, and long-term OC use are not associated with HPV prevalence, but rather these factors might be involved in the transition from HPV infection to neoplastic cervical lesions. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2148–53)

In epidemiology, it is necessary that exposure indicators have good validity in order to obtain valid results when measuring the risks associated with occupational exposure to environmental noxious agents. However, ensuring the validity of past exposure data is no easy task. Because there are no environmental hygiene measures or representative levels of bioindicators signaling past exposure, self-reports have been used as a source of indirect exposure data. Unfortunately, data on specific agents are commonly poor and need to be complemented with data on the determinants of exposure. The validity of self-reports improves when certain techniques, such as control lists and icons, are employed, and the quality of individual exposure data improves when secondary data on exposure and its conditioning or determining factors are incorporated. Exposure can be determined by means of exposure matrices, assessment by experts, and exposure models, and by using a combination of primary and secondary data on exposure and its conditioning factors. Matrices contain pooled data and can thus lead to errors in classifying individual exposure and to biased risk estimates. Assessment by experts is probably the method with the highest validity, but it can become expensive when studies are large. It is also feasible to use a formal model for assessing perceivable exposures, complemented with expert assessments whenever the results of the model appear to deviate from reality.

Texto completo del documento La validez de los indicadores de exposición es una condición necesaria en epidemiología si se han de obtener resultados válidos en la medición de los riesgos asociados con la exposición a agentes nocivos en el entorno laboral. Sin embargo, llevar a cabo la validación de estos indica dores de exposiciones pasadas no es tarea fácil. Debido a la falta de mediciones de referencia en el ámbito de la higiene industrial y de con centraciones representativas de bioindicadores que reflejen las exposiciones pasadas, el método de los autoinformes se ha utilizado para recoger datos de exposición indirectos. No obstante, los datos acerca de agentes nocivos específicos son a menudo deficientes y deben completarse con otros sobre los factores condicionantes de la exposición. La validez de los autoinformes me jora cuando se utilizan listas de verificación e iconos ilustrativos, mientras que la calidad de la información sobre las exposiciones personales mejora cuando se incorporan datos secundarios acerca de las exposiciones y de los factores que las condicionan o determinan. La exposición se puede determinar mediante matrices de exposición, evaluación por exper tos y modelos de exposición, integrando datos primarios y secundarios acerca de las exposicio nes y sus factores condicionantes. Las matrices contienen datos agrupados y, por consiguiente, pueden llevar a errores a la hora de clasificar las exposiciones individuales e introducir sesgos en la estimación de los riesgos. La evaluación por expertos es probablemente el método con el índice de validez más alto, pero puede entrañar costos muy altos en el caso de estudios de cierta magnitud. Otra posibilidad con buenas perspectivas es la de utilizar un modelo formal para evaluar las exposiciones pa tentes y mejorarlo mediante la evaluación por expertos en situaciones en las cuales los resul tados del modelo parezcan alejarse de la realidad. Universidad Nacional, Costa Rica. Instituto Regional de Estudios en Sustancias Tóxicas

The natural course of Chlamydia trachomatis infection and its risk factors were studied in Colombian women with normal cytological results, during a 5-year period. Eighty-two women who were found to be positive for C. trachomatis at the start of the study were studied at 6-month intervals. At each visit, a cervical scrape sample was obtained for detection of C. trachomatis by use of C. trachomatis endogenous-plasmid polymerase chain reaction (PCR)-enzyme immunoassay and VD2-PCR-reverse line blot assay. Of the women studied, 67% had a single-serovar infection, 10% had a mixed-serovar infection, and 23% had an infection with an unidentified type. An inversed rate of clearance of C. trachomatis infection was observed with oral contraceptive use (hazard ratio [HR], 1.7 [95% confidence interval {CI}, 1.1-2.7]) and first sexual intercourse at >/=20 years of age (HR, 4.3 [95% CI, 2.3-8.0]). Serovars of group B (B, D, and E) and C (H, I, J, and K) had a decreased rate of clearance (rate ratio, 0.4 [95% CI, 0.1-0.9]), compared with that for serovars of the intermediate group (F and G). At 4 years of follow-up, 94% of the women had cleared their infections.

Ciertos tipos de VPH son los agentes etiológicos de cáncer cervical, lesiones tempranas y ulceras genitales (1-4). Las infecciones por VPH tienen alta prevalencia y se transmiten por contacto sexual (5-6). Los datos publicados sobre incidencia son en mujeres jóvenes pero son escasos los datos en mujeres de mediana edad (7-10). Se sugiere que los VPH de alto riesgo tienen mayor duración que los de bajo riesgo (7-11). Para examinar estos aspectos se presentan los datos sobre una cohorte de 2,200 mujeres seguidas desde Noviembre de 1993 a julio del 2001 en Bogotá, sexualmente activas, entre 13-85 años de edad. Se realizó detección y tipificación del VPH mediante PCR estándar GP5+/GP6+ e inmunoensayo enzimático (EIA). Para el cálculo de la incidencia se usaron métodos de persona-tiempo, asumiendo que la infección se presentó en la mitad de periodo entre la última visita negativa a VPH y la siguiente positiva. Para este análisis se tomaron 1,610 mujeres después de excluir las infecciones prevalentes. La duración media de seguimiento por paciente fue de 4,1 años (Rango intercuartil RIQ 3.2-5.0), la mediana de seguimiento fue de 7 meses (RIQ 6.0-12.0), más del 65% de las mujeres tenían 4 visitas y la edad media fue de 32,3 años (RIQ 26,5-39,2). La incidencia para infección por VPH fue de 6,2 por 100 personas-año, siendo la incidencia mayor para los tipos de alto riesgo que para los de bajo riesgo. Los tipos de mayor incidencia fueron los VPH 16, 58, 31 y 18. La curva de incidencia por edad mostró una forma bimodal, con un pico de incidencia de 15-19 años, que decrece hasta alrededor de los 50 años, cuando presenta un pequeño incremento. El riesgo acumulado a los 5 años para una infección por VPH es mayor en grupos jóvenes (42.5%) que en mayores de 45 años (12,4%). La duración de las infecciones fue mayor para los VPH de alto riesgo 14,8 meses) que para los de bajo riesgo (11,1 meses). Los factores asociados a un mayor riesgo de adquisición de infecciones nuevas fueron edad joven, embarazo y nuevos compañeros sexuales. Estos resultados ayudan a tener un mejor cuadro de la historia natural de las infecciones por VPH en mujeres de edad media. REFERENCIAS 1. MUÑOZ N, BOSCH X, DE SANJOSE S, et al. Epidemiologic Classification of Human Papillomavirus Types Associated with Cervical Cancer. N Engl J Med 2003; 348: 518-27. 2. IARC MONOGRAPHS ON THE EVALUATION OF CARCINOGENIC RISKS TO HUMANS. Vol. 64. Human papillomaviruses. Lyon, France: International Agency for Research on Cancer, 1995. 3. SCHIFFMAN M, KRUGER-KJAER S. Natural History of Anogenital Human Papillomavirus Infection and Neoplasia. J Natl Cancer Inst Monographs 2003; 31: 14-9. 4. FRANCO EL, VILLA LL, SOBRINHO JP, et al. Epidemiology of acquisition and clearance of cervical human papillomavirus infection in women from a high-risk area for cervical cancer. J Infect Dis 1999; 180:1415-23. 5. MOLANO M, POSSO H, WEIDERPASS E, et al. Prevalence and determinants of HPV infection among Colombian women with normal cytology. Br. J. Cancer 2002; 87(3):324-33. 6. HERRERO R, HILDESHEIM A, BRATTI C, et al. Populationbased study of human papillomavirus infection and cervical neoplasia in rural Costa Rica. J Natl Cancer Inst 2000; 92: 464-74. 7. HO GYF, BIERMAN R, BEARDSLEY L, CHANG CJ, BURK RD. Natural history of cervicovaginal papillomavirus infection in young women. N Engl J Med 1998; 338:423-8. 8. WOODMAN CBJ, COLLINS S, WINTER H, et al. Natural history of cervical human papillomavirus infection in young women: a longitudinal cohort study. Lancet 2001; 357:1831-6. 9. MOSCIKCI AB, HILLS N, SHIBOSKI S, et al. Risk for Incident human papillomavirus infection and low grade squamous intraepithelia lesion development in young females. J Amer Med Assoc 2001; 285:2995-3002. 10. WINER RL, LEE SK, HUGHES JP, ADAM DE, KIVIAT NB, KOUTSKY LA. Genital human papillomavirus infection: incidence and risk factors in a cohort of female university students. Am J Epidemiol 2003; 157(3): 218-26. 11. HILDESHEIM A, GRAVITT P, SCHIFFMAN MH, et al. Determinants of genital human papillomavirus infection in lowincome women in Washington, DC. Sex Transm Dis 1993; 20: 279-85.

Introducción: El virus del papiloma humano es el principal factor de riesgo asociado con el desarrollo de cáncer cervical, uno de los cánceres más comunes en mujeres colombianas. En Colombia, donde las tasas de incidencia de cáncer cervical son altas, se tiene poca información acerca de la prevalencia de la infección y no se tienen datos de seguimiento sobre la persistencia o eliminación de la infección y los factores de riesgo asociados. En este reporte se presentan los resultados de la prevalencia de la infección por HPV y los factores de riesgo asociados en mujeres que tuvieron una citología normal al comienzo del estudio así como el seguimiento de 227 mujeres positivas para la infección por HPV durante un periodo de cinco años, en la ciudad de Bogotá, Colombia. Materiales y Métodos: 1859 mujeres con citología normal firmaron un consentimiento escrito y respondieron a un cuestionario estructurado. La presencia de HPV fue analizada mediante PCR con el uso de los iniciadores GP5+/ GP6+, que amplifican para un fragmento de 140 pb de la región L1/HPV (1) y tipificadas por medio del ensayo de EIA para la identificación de 37 diferentes tipos de HPV (2). Se calcularon riesgos relativos para eliminación de la infección por HPV mediante el uso de curvas de supervivencia. Resultados: La prevalencia de la infección fue de 14.8%; 9% de las mujeres fueron infectadas por HPV de alto riesgo, 3.1% por HPV de bajo riesgo, 2.3% por ambos tipos virales y 0.4% por HPV indeterminados. Se identificaron 32 diferentes tipos de HPV, siendo el HPV16, 58, 56, 81 y 18, los tipos mas comunes. La prevalencia de la infección por HPVs de alto riesgo entre mujeres jóvenes (menores de 20 años) fue de 26.1%, en mujeres con edades entre 45 y 54 años fue de 2.3% y en mujeres mayores de 55 años o mas fue de 13.2%. Para HPV de bajo riesgo, el mayor pico de prevalencia se observó en mujeres mayores de 55 años. Comparadas con mujeres en edades entre 35-44 años, las mujeres menores de 20 años tuvieron un mayor riesgo (10 veces) de tener infecciones múltiples. La edad, el número de compañeros sexuales regulares y el uso de anticonceptivos orales fueron los principales factores de riesgos asociados con la infección por HPV. En mujeres menores de 25 años, el alto nivel educacional y el tener compañeros sexuales casuales fueron factores de riesgo asociados con la infección. Durante el seguimiento de las las infecciones por HPV, 16 tuvieron una tasa de eliminación significativamente mas lenta que las infecciones por HPV de bajo riesgo (RR = 0.47, 95% IC: 0.32-0.72), tipos relacionados a HPV 16 (tipos 31, 33, 35, 52, 58) tuvieron tasas de eliminación intermedias (RR = 0.62, 95% IC: 0.47-0.94), los demás tipos de alto riesgo no mostraron diferencias en la tasa de eliminación cuando se compararon con HPVs de bajo riesgo. Infecciones singulares y múltiples tuvieron tasas de eliminación similares. Tampoco se observó una evidencia clara de asociación entre carga viral y eliminación de la infección. En mujeres con paridades se observó una tasa de eliminación de la infección mas lenta que en mujeres nulíparas (RR = 0.64, 95% IC: 0.47-0.89) y en mujeres que han usado alguna vez anticonceptivos, orales se observó una tasa de eliminación de la infección mas rápida que en mujeres que no han usado anticonceptivos orales (RR = 1.38, 95% IC: 1.07-1.77). Conclusión: Hay una amplia diversidad de infecciones por HPV en la cohorte analizada, siendo los HPV de alto riesgo los tipos más comunes. En esta población múltiples compañeros sexuales y entre mujeres jóvenes un alto nivel de educación y compañeros sexuales casuales parecen determinar el riesgo de infección. Las infecciones por HPV16 son eliminadas en un periodo mas largo que otras infecciones por HPVs de alto y bajo riesgo. REFERENCIAS 1. DE RODA HUSMAN AM, WALBOOMERS JMM, VAN DER BRULE AJC, MEIJER CJLM AND SNIJDERS PJF. The use general primers GP5 and GP6 elongated at their 3' ends with adjacent highly conserved sequences improves human papilomavirus detection by PCR. J Gen Virol 1995; 76:1057-62. 2. JACOBS MV, WALBOOMERS JMM, SNIJDERS PJF, VOORHORST FJ, DAALMEIJER NF AND MEIJER CJLM. Age-related distribution patterns of 37 mucosotropic HPV types in women with citologically normal cervical smears: Decreased high risk/low risk ratio at older age. Int J Cancer 2000; 87(2): 221-27.

Objectives: Chlamydia trachomatis infection in the cervix and uterus has been hypothesised to be a co-factor for cervical cancer. We performed a cross sectional study in Bogota, Colombia, where cervical cancer rates are high, to determine the prevalence and determinants of C trachomatis infection, and in particular its association with human papillomavirus (HPV). Methods: 1829 low income sexually active women were interviewed and tested for C trachomatis, using an endogenous plasmid PCR-EIA, and for 37 HPV types, using a general primer GP5+/6+ mediated PCR-EIA. Results: The overall prevalence of C trachomatis was 5.0%, and it did not differ substantially between women with normal (5.0%) and those with abnormal (5.2%) cervical cytology. Women infected with any HPV type (15.1%) had a slightly increased risk of being simultaneously infected with C trachomatis (adjusted OR 1.3, 95% CI: 0.8 to 2.4). This association was stronger when multiple HPV infections (adjusted OR 2.5, 95% CI: 1.1 to 5.9) were present. No other lifestyle or reproductive characteristics were clearly associated with risk of C trachomatis infection. Conclusions: HPV infected women, particularly women with multiple HPV infections, are at increased risk of being infected with C trachomatis.

Helicobacter pylori is recognized as an etiologic agent of several gastric diseases. Bacterial genotypes have been related to clinical outcome in several populations.To compare cagA, vacA and iceA genotypes of Colombian isolates from patients with several gastrointestinal diseases, including gastric cancer.We used polymerase chain reactions to amplify vacA, cagA and iceA genes of 137 H pylori isolates coming from 26 patients with gastric cancer (GC), 34 with peptic ulcer (PU), 19 with intestinal metaplasia (IM), 23 with atrophic gastritis (AG) and 35 with non atrophic gastritis (NAG).vacA s1-m1, cagA+, iceA+ were the most frequently found genotypes. vacA s1 and m1 subtypes were found in 92 (67%) and 82 (60%) cases respectively. Sixty three percent were cagA+ and 85% were iceA+. There was a lower prevalence of s1 allele in cases of NAG (43%), compared with GC, PU and IM (81%, 77% and 81% prevalence, respectively, p0.01). Isolates from NAG also showed a low frequency of vacA m1 subtype (40%) compared with GC or IM (81% and 84% respectively, p0.01). The prevalence of cagA+ strains was significantly higher in GC patients (80%) than in NAG patients (51.4%, p0.01). No differences in the frequency of vacA s1a, s1b and iceA subtypes, were observed.A lower frequency of cytotoxic H pylori genotypes such as cagA and vacA s1m1 and a higher frequency of non cytotoxic genotypes, was observed in patients with NAG, when compared to patients with GC or PU. These results suggest that even in Colombia, vacA and cagA could be used as markers of increased virulence.

Background: Helicobacter pylori is recognized as an etiologic agent of several gastric diseases. Bacterial genotypes have been related to clinical outcome in several populations. Aim: To compare cagA, vacA and iceA genotypes of Colombian isolates from patients with several gastrointestinal diseases, including gastric cancer. Material and methods: We used polymerase chain reactions to amplify vacA, cagA and iceA genes of 137 H pylori isolates coming from 26 patients with gastric cancer (GC), 34 with peptic ulcer (PU), 19 with intestinal metaplasia (IM), 23 with atrophic gastritis (AG) and 35 with non atrophic gastritis (NAG). Results: vacA s1-m1, cagA+, iceA+ were the most frequently found genotypes. vacA s1 and m1 subtypes were found in 92 (67%) and 82 (60%) cases respectively. Sixty three percent were cagA+ and 85% were iceA+. There was a lower prevalence of s1 allele in cases of NAG (43%), compared with GC, PU and IM (81%, 77% and 81% prevalence, respectively, p