[Sex-hormone binding globulin (SHBG) levels during pregnancy as predictors for pre-eclampsia and fetal growth restriction]. / Evaluación de la globulina transportadora de hormonas esteroidales (SHBG) durante el embarazo como factor predictor de pre-eclampsia y restricción del crecimiento intrauterino.

BACKGROUND: Sex-Hormone Binding Globulin (SHBG) may be associated to Pre-eclampsia (PE) and Fetal Growth Restriction (RCIU). AIM: To determine if maternal serum SHBG concentrations during the first and second trimesters are predictive biomarkers of Pre-eclampsia and RCIU. PATIENTS AND METHODS: Prospective cohort study carried out in the Fetal Medicine Unit, Universidad de Chile Clinical Hospital between January, 2005 and December, 2006. Blood samples were obtained from unselected pregnant women during routine 11-14 week and 22-25 week ultrasound examinations, conforming two different study groups. Posteriorly, serum SHBG concentrations were determined in women who developed Pre-eclampsia, RCIU and their respective controls. RESULTS: Fifty five patients were included in the 11-14 weeks group. Nine women that developed PE, 10 that developed RCIU and 36 controls were selected from this group. There were no significant differences in SHBG levels between patients with PE, RCIU or controls (324.7 (26.6), 336.8 (33.9) and 377.5 (24.3) nmol/L, respectively). Fifty four women were included in the 22-25 weeks group. Eight women who developed Pre-eclampsia, 15 who developed RCIU and 31 controls were selected. Again, there were no significant differences in SHBG levels between patients with PE, RCIU or controls (345.5 (151.1), 383.8 (143.4) and 345.5 nmol/l (151.1), respectively). CONCLUSIONS: Maternal SHBG serum levels did not predict subsequent development of Pre-eclampsia and RCIU.

Inhibitory effect of nordihydroguaiaretic acid and its tetra-acetylated derivative on respiration and growth of adenocarcinoma TA3 and its multiresistant variant TA3MTX-R.

The effects of nordihydroguaiaretic acid (NDGA) and its tetraacetylated derivative (NDGATA) on the growth, oxygen consumption, adenosine 5'-triphosphate (ATP) level and viability of mouse mammary adenocarcinoma TA3 and its multiresistant variant TA3-MTX-R cell lines were determined. NDGA inhibited mitochondrial carbonyl cyanide m-chlorophenylhydrazone (CCCP)-stimulated oxygen consumption in mouse liver and tumor cells when glutamate plus malate or succinate was added as substrate. The effects were considerably weaker when respiration was supported by duroquinol, indicating that NDGA inhibited primarily mitochondrial electron flow located at some point before ubiquinone. Although NDGATA only inhibited the electron flow through complex I, it was more efficient and selective than NDGA because mouse liver mitochondria were significantly less sensitive to it than both tumor cell lines tested. NDGA and NDGATA inhibited mitochondrial ATP synthesis and, consequently, cell viability and growth rate were also decreased. NDGA and NDGATA inhibited the growth of intramuscularly implanted tumor cells, indicating that NDGATA was also antineoplastic in vivo. In conclusion, NDGATA is cytotoxic to tumor cells, provoking selective induction of mitochondrial dysfunctions, which could be interesting as potential antitumoral agent.

[Acute and long-term clinical results of bare metal coronary stenting]. / Resultados clínicos inmediatos y alejados del implante de stents metálicos no recubiertos. Se justifica un reemplazo total por los stents liberadores de drogas?

BACKGROUND: Since the introduction of stents in 1994, improved clinical results have boosted the development of coronary angioplasty in Chile. Drug eluting stents, that have a reduced rate of restenosis, are being increasingly used. AIM: To assess the acute and long-term results of bare metal stent implantation. PATIENTS AND METHODS: Acute and long-term clinical, procedural and angiographic results were assessed in non acute myocardial infarction patients undergoing coronary stent implantation between August 1996 and December 2003. RESULTS: During the study period, 932 patients aged 30 to 87 years (194 women) had at least one stent implanted. Twenty two percent were diabetic, 33% had recent myocardial infarction, 53% unstable angina and 22% stable angina. Angiographic and clinical success were 99.6% and 98.2%, respectively. In hospital death was 0.5%. During a mean follow-up of 19.1 months, all cause mortality was 3.9%, cardiac death 1.9% and survival free of major cardiac ischemic events was 85.3%. Only 6.4% of lesions underwent target vessel revascularization (TVR). Independent predictors of TVR were previous surgery, left anterior descending artery, small post stent minimum luminal diameter. Ostial location, in-stent restenosis, and younger age were non significant predictors. CONCLUSIONS: Acute and long-term results of bare metal stents in this population were excellent. An intriguingly low rate of TVR was seen. Selective bare metal stenting should continue in lesions and patients with a low risk of clinical restenosis.

[Hierarchical clustering analysis to detect associations between clinical and pathological features of gastric tumors and hypermethylation of suppressor genes]. / Identificación de asociaciones clínico-patológicas e hipermetilación de genes supresores de tumores en cáncer gástrico difuso a través de análisis de Hierarchical clustering.

BACKGROUND: Methylation is an inactivation mechanism for tumor suppressor genes, that can have important clinical implications. AIM: To analyze the methylation status of 11 tumor suppressor genes in pathological samples of diffuse gastric cancer. MATERIAL AND METHODS: Eighty three patients with diffuse gastric cancer with information about survival and infection with Epstein Barr virus, were studied. DNA was extracted from pathological slides and the methylation status of genes p14, p15, p16, APC, p73, FHIT, E-cadherin, SEMA3B, BRCA-1, MINT-2 y MGMT, was studied using sodium bisulphite modification and polymerase chain reaction. Results were grouped according to the methylation index or Hierarchical clustering (TIGR MultiExperiment Viewer). RESULTS: Three genes had a high frequency of methylation (FHIT, BRCA1, APC), four had an intermediate frequency (p15, MGMT, p14, MINT2) and four had a low frequency (p16, p73, E-cadherin, SEMA3B). The methylation index had no association with clinical or pathological features of tumors or patients survival. Hierarchical clustering generated two clusters. One grouped clinical and pathological features with FHIT, BRCA1, and APC and the other grouped the other eight genes and Epstein Barr virus infection. Two significant associations were found, between APC and survival and p16/p14 and Epstein Barr virus infection. CONCLUSIONS: Hierarchical clustering is a tool that identifies associations between clinical and pathological features of tumors and methylation of tumor suppressor genes.

Identificación de asociaciones clínico-patológicas e hipermetilación de genes supresores de tumores en cáncer gástrico difuso a través de análisis de Hierarchical clustering / Hierarchical clustering analysis to detect associations between clinical and pathological features of gastric tumors and hypermethylation of suppressor genes

Background:Methylation is an inactivation mechanism for tumor suppressor genes, that can have important clinical implications. Aim: To analyze the methylation status of 11 tumor suppressor genes in pathological samples of diffuse gastric cancer. Material and methods: Eighty three patients with diffuse gastric cancer with information about survival and infection with Epstein Barr virus, were studied. DNA was extracted from pathological slides and the methylation status of genes p14, p15, p16, APC, p73, FHIT, E-caderin, SEMA3B, BRCA-1, MINT-2 y MGMT, was studied using sodium bisulphite modification and polymerase chain reaction. Results were grouped according to the methylation index or Hierarchical clustering (TIGR MultiExperiment Viewer). Results: Three genes had a high frequency of methylation (FHIT, BRCA1, APC), four had an intermediate frequency (p15, MGMT, p14, MINT2) and four had a low frequency (p16, p73, E-cadherin, SEMA3B). The methylation index had no association with clinical or pathological features of tumors or patients survival. Hierarchical clustering generated two clusters. One grouped clinical and pathological features with FHIT, BRCA1, and APC and the other grouped the other eight genes and Epstein Barr virus infection. Two significant associations were found, between APC and survival and p16/p14 and Epstein Barr virus infection. Conclusions: Hierarchical clustering is a tool that identifies associations between clinical and pathological features of tumors and methylation of tumor suppressor genes.

Ketamina endovenosa preoperatoria mejora la analgesia postoperatoria de colecistectomías laparoscópicas / Preoperative intravenous ketamine improves analgesia alter laparoscopic cholecystectomy

El adecuado tratamiento del dolor agudo postoperatorio es un desafío actual y real. La utilización de analgesia preventiva con ketamina puede ser de alta utilidad, ya que prevendría la sensibilización central mediada por receptores n-metil-diaspartato (NMDA). Objetivo: evaluar el uso preincisión de colecistectomías laparoscópicas de 0,15 mg/kg de ketamina EV. Resultados: en 84 pacientes adultos con edad promedio de 52 +/- 9 años se logró una disminución significativa del dolor postoperatorio con el uso de ketamina EV preoperatoria. La evaluación visual análoga (EVA) de dolor fue significativamente menor en las 72 horas postoperatorias estudiadas. La cantidad de analgésico de rescate (morfina) consumida fue significativamente menor en el grupo que recibió ketamina siendo en promedio de 1,7 mg/por paciente en 24 horas versus el grupo que recibió placebo, que fue de 4,2 mg/por paciente en 24 horas (p<0.01). No se registraron episodios de malos recuerdos intraoperatorios y agitación en el despertar anestésico en ninguno de los grupos. La incidencia de náuseas y vómitos no tuvo diferencias estadísticamente significativas entre los enfermos. El grado de satisfacción fue en general muy bueno y bueno en ambos grupos y no se evidenció diferencias entre ambos, pero los únicos dos casos que evaluaron su analgesia como mala se ubicaron en el grupo que recibió placebo. Con respecto a incidencia de pesadillas o alucinaciones, ningún paciente refirió haberlas presentado hasta 14 días postoperatorios. Conclusión: el uso de dosis bajas de ketamina EV en el preoperatorio de colecistectomías laparoscópicas es altamente recomendable, ya que proporciona una buena calidad analgésica, disminuyendo la necesidad de utilizar fármacos de rescate.

Backround: Treating acute postoperative pain is challenging. Preemptive analgesia with ketamine can be useful as it prevents central sensibilitation inhibiting NMDA receptors. Objective: To test a pre insision dose of 0.15 mg/kg ketamine during laparoscopic cholecystectomy. Results: 84 patients were studied divided in two groups; group ketamine and group placebo. Acute postoperative pain was significantely lower in the ketamine group. VAS scores were lower for the 72 postoperative hours studied in patients receiving ketamine. Rescue analgesia (morphine) was 1.7 mg/patient for 24 hours in the ketamine group comparing it with the control group which was 4.2 mg/patient in 24 hours (p<0.01). Postoperative agitation, bad recalls or nightmares were absent in both groups. Postoperative nausea or vomiting had no difference comparing the groups. Patient satisfaction was evaluated good and very good by the mayority of them. There were two cases evaluating analgesic treatment as not good. Both received placebo. Conclusion: Preoperative ketamine was useful because it prometed good analgesia and because it lower the use of rescue analgesia.

[Clinical and molecular features of cardial gastric cancer associated to Epstein Barr virus]. / Características clínico-moleculares del cáncer gástrico cardial asociado al virus Epstein Barr.

BACKGROUND: Mortality caused by cardial gastric cancer in Chile, is increasing. Previously we demonstrated an association between Epstein Barr virus and this specific location of gastric cancer. AIM: To perform a clinical and molecular characterization of cardial gastric cancer associated to Epstein Barr virus. MATERIAL AND METHODS: Epstein Barr virus was identified in 93 cardial gastric tumors, by in situ hybridization. Clinical and pathological features, survival and expression of p53 and c-erbB2 were compared between tumors with or without the presence of the virus. RESULTS: Twenty two (23.6%) tumors expressed Epstein Barr virus. No difference in sex or age of patients with tumors positive or negative for the virus was observed. Epstein Barr positive tumors had a tendency to have a higher frequency of Bormann III endoscopic appearance and a lower frequency of p53 accumulation (p=0.06). Five years survival was 67% and 42% of tumors positive and negative for the presence of the virus, respectively (p=0.57). CONCLUSIONS: Our results, although not significant, show a tendency towards unique characteristics of cardial gastric tumors associated to Epstein Barr.

Predictive factors of stenosis after stapled colorectal anastomosis: prospective analysis of 179 consecutive patients.

The incidence, risk factors, and clinical relevance of stenosis of stapled colorectal anastomosis (CRA) were studied prospectively. Anastomotic stricture was defined as the inability of traversing the anastomosis with the rigid proctoscope. The population studied consisted of 179 patients (94 males) with an average age of 59.3 years (range: 20 to 91 years). The main indication for surgery was colorectal cancer in 59% of the cases, followed by diverticular disease in 23%. The first endoscopic control was performed before 4 months in 25% of the patients, between 5 and 10 months in 50%, and during the following 10 months in 25%. Stenosis was verified with the rigid instrument in 21.1% of the cases and with the flexible colonoscope in 4.4%. The barium enema performed in 12 cases confirmed a punctiform stenosis in 5 patients, 4 of whom had been asymptomatic. An endoscopic dilatation was performed on 5 of the 8 symptomatic patients, with one relapse that required an additional dilatation. In the univariate analysis only the lesser 4-month interval was statistically significant (p = 0.033; odds ratio (OR) = 2.3; confidence interval (CI) 95% = 1.06 to 4.97). Male patients (p = 0.057; OR = 2.08; IC 95% = 0.97-4.44) show a tendency to CRA stricture that does not reach statistically significant levels. In the multivariate analysis, only sex (p = 0.04; OR = 4.11; IC 95% = 1.03 to 5.41) and the time interval (p = 0.012; OR = 2.87; IC 95% = 1.25 to 6.57) appear as independent variables in stenosis risk of a stapled CRA. The incidence of this complication depends on the criteria used for defining it. It is clinically relevant in no more than 5% of the patients. Five out of eight patients in category II were treated successfully with an endoscopic dilatation, while the other three improved spontaneously. Early stenosis, although frequent, is generally asymptomatic and disappears spontaneously. Considering the lack of correlation between the degree of stricture and its symptomatology, it is convenient to combine both the anatomic and the clinical criteria in the selection of candidates for an eventual therapeutic procedure.

Rofecoxib preoperatorio disminuye consumo de morfina postiroidectomía / Rofecoxib preoperative consumption diminishes of morphine postiroidectomia

Introducción: El uso de antiinflamatorios no esteroidales (AINEs) como parte de un tratamiento analgésico balanceado busca disminuir el uso de opioides y así sus efectos adversos. Los COX-2 cumplirían esta función, pero además al no interferir con la función plaquetaria, no aumentarían el sangrado postoperatorio en tiroidectomías. Métodos: 57 pacientes fueron randomizados a recibir placebo (control) o rofecoxib 50 mg VO 2 horas preoperatorias. Luego de una anestesia general balanceada todos los pacientes fueron conectados a una bomba PCA de morfina. Se estudió la cantidad de morfina utilizada en 24 horas, la evaluación del dolor, el sangrado postoperatorio (midiendo el débito del drenaje), el hematocrito a las 24 horas, la satisfacción de los pacientes y las reacciones adversas. Resultados: El consumo de morfina fue significativamente menor en el grupo rofecoxib, 10 ± 9,98 mg versus el control que fue de 19,3 ± 9,56 mg (p=0,0018). Lo que significó un consumo 50,1 por ciento menor en este grupo. El dolor que presentó el grupo control fue significativamente superior. El sangrado postoperatorio no tuvo diferencia, 55 ± 30 ml/24 horas en el control y 68 ± 38 ml/24 horas en el grupo rofecoxib (p=0,188). La incidencia de náuseas y vómitos postoperatorios fue significativamente superior en el grupo control, (9 de 23, versus 2 de 25) (p=0,001). La satisfacción de los pacientes fue buena y muy buena en el grupo rofecoxib, mientras que en el grupo control hubo 6 enfermos (22 por ciento) que consideraron su analgesia sólo como regular. Conclusión: rofecoxib demostró disminuir el consumo de morfina en un 50 por ciento, sin aumentar el sangrado postoperatorio al compararlo con el grupo control.

Incidencia y predictores del deterioro de la función renal en pacientes sometidos a angioplastía coronaria / Incidence and predictors of the renal function deterioration in patients submitted to coronary angioplasty

La insuficiencia renal aguda (IRA) puede ser una complicación de la angioplastia coronaria (AC). En su patogenia participan variables inherentes al paciente como relacionadas al procedimiento. El objetivo de este estudio fue evaluar la incidencia y predictores de IRA en pacientes sometidos a AC. Analizamos a 913 pacientes sometidos a AC entre 08/1998 y 07/2003. Sólo 42 (4,6 por ciento) pacientes desarrollaron IRA (aumento de la creatinemia ≥ 0,5 mg/dl respecto del basal). Los predictores independientes de IRA fueron: edad (p=0,002; OR = 1,04), creatininemia basal (p < 0,001; OR = 4,00), caída del hematocrito (p = 0,001; OR = 1,15), insuficiencia cardiaca (p < 0,01; OR = 7,74), shock (p = 0,006; OR = 8,49) y la cantidad de medio de contraste (p = 0,006; OR = 1,005). Conclusiones: La IRA es una complicación poco frecuente de la angioplastia coronaria. La mayor edad, el daño renal previo, la pérdida sanguínea, el estado hemodinámico y el mayor volumen de medio de contraste usado son los predictores independientes de su ocurrencia.

Porcentaje de cmmpromiso de lesion cervical de lto grado y persistencia de enffermedad residual postcono

El objetivo de este trabajo fue evaluar la relación entre el porcentaje de cuello comprometido por neoplasia intraepitelial de alto grado en pacientes conizadas por asa leep y la persistencia de lesión residual en la pieza de histerectomía. Se presentan 78 casos de pacientes conizadas por asa leep y que posteriormente fueron sometidas a histerectomía entre junio de 1994 y diciembre del 2000 por enfermedad residual u otra patología ginecológica concomitante. Una vez obtenida la pieza de conización esta fue analizada en anatomía patológica evaluando el porcentaje de muestras comprometidas por nie de alto grado y se comparo con la persistencia de enfermedad en la pieza de histerectomía. Encontramos un valor significativamente estadístico entre el porcentaje de muestras comprometidas y la persistencia de enfermedad.

The objetive of this research was to compare the percentage of persistence of residual lesion on hysterectomy specimen after a cone biopsy done with leep (loop electroexcision procedure) in patients with "high grade SIL" (squamous intraepithelial lesion). We present 78 patients that a cone biopsy with leep was done and subsequently had a histerectomy, between June 1994 and December 2000, for residual disease or other gynecological conditions. The pathology reports were statistically significant in between the percentage of compromised cervical biopsies and the persistence of disease in the uterus.

Niveles de colesterol y accidente vascular hemorrágico: un estudio de casos y controles en Chile / Blood cholester level and hemorrhagic stroke: a case control study in Chile

Objetivo: estudiar el colesterol sérico como factor de riesgo en el accidente vascular encefálico hemorrágico. Diseño: es un estudio de casos y controles, asumiendo un riesgo relativo de 2, un Alfa de 0,20, 15 por ciento de prevalencia de colesterol alto en los controles,la muestra mínima fue de 112 casos y 112 controles. Pacientes: corresponden a pacientes prospectivos al hospital J.J. Aguirre, de la Universidad de Chile entre agosto de 1992 y julio de 1994. Todos ellos tenían tomografía cerebral. Los controles fueron pacientes ingresados a otras unidades del Hospital Clínico, sin el diagnóstico de hemorragia cerebral y fueron pareados por edad y sexo con los casos. Otras variables estudiadas fueron: diabetes, alcohol, enfermedad hepática, uso crónico de medicamentos. Se analizó utilizando STATA 3.1 empleando análisis pareado y análisis de regresión logística condicional

Evaluación prospectiva de los colirios de tobramicina-dexametasona versus ciprofloxacino-dexametasona en cuanto a penetración y tolerancia ocular / Prospective evaluation of tobramycin-dexametasone eye drops versus ciprofloxacin-dexametasone in the ocular penetration and tolerance

El colirio de tobramicina-dexametasona se utiliza frecuentemente en el postoperatorio de la catarata y la combinación de ciprofloxacino-dexametasona parece una combinación interesante por el amplio espectro del antibiótico, sin embargo nomse encuentra disponible actualmente en el mercado. El objetivo de este trabajo fue comparar la capacidad de penetración de ambos antibióticos a cámara anterior y la tolerancia postoperatoria evaluando el grado de conjuntivitis, queratitis e inflamación intraocular. Se obtuvieron muestras de 0.1 cc de humor acuoso media hora después de instilar 2 gotas de uno u otro colirio sobre la córnea y sólo se logró detectar ciprofloxacino con un promedio de 0,35 microgramos por ml. No fue posible detectar niveles de Tobramicina en ninguna de las muestras. la evaluación postoperatoria no demostró diferencias estadísticamente significativas en cuanto a tolerancia, grado de conjuntivitis, queratitis e inflamación intraocular entre ambos colirios con un P<0.05

Factores psicosociales relacionados con accidentes del trabajo / Psychosocial factors related with work accidents

Se compararon 22 pacientes accidentados en el trabajo que habían sufrido una amputación grave, con 22 trabajadores en máquinas industriales de un riesgo similar a las que habían producido los accidentes, pareados por edad. Ambos grupos fueron investigados mediante encuestas en las que se obtiene información relevante previa al accidente, sobre condiciones de trabajo, sintomatología neurótica y psicosomática, nivel de estrés y cambios vitales. Los resultados mostraron que los dos grupos fueron similares en nivel educacional, estado civil y situación laboral. Los pacientes amputados tenían menor tiempo de experiencia en el trabajo, mayor cantidad de eventos vitales en los últimos 6 meses, y mostraron un nivel significativamente menor de sintomatología neurótica y psicosomática , así como de estrés laboral y extra-laboral. Se plantea que un período de shock emocional inmediatamente posterior al accidente puede explicar estos resultados. También se plantea que el mecanismo de actuación pueda ser relevante en el funcionamiento psicológico de los pacientes amputados