Browsing by Author "Padilla, Oslando"

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    11 beta-hydroxysteroid dehydrogenase type-2 and type-1 (11 beta-HSD2 and 11 beta-HSD1) and 5 beta-reductase activities in the pathogenia of essential hypertension
    (HUMANA PRESS INC, 2010) Campino, Carmen; Carvajal, Cristian A.; Cornejo, Javiera; San Martin, Betty; Olivieri, Oliviero; Guidi, Giancesare; Faccini, Giovanni; Pasini, Francesco; Sateler, Javiera; Baudrand, Rene; Mosso, Lorena; Owen, Gareth I.; Kalergis, Alexis M.; Padilla, Oslando; Fardella, Carlos E.
    Cortisol availability is modulated by several enzymes: 11 beta-HSD2, which transforms cortisol (F) to cortisone (E) and 11 beta-HSD1 which predominantly converts inactive E to active F. Additionally, the A-ring reductases (5 alpha- and 5 beta-reductase) inactivate cortisol (together with 3 alpha-HSD) to tetrahydrometabolites: 5 alpha THF, 5 beta THF, and THE. The aim was to assess 11 beta-HSD2, 11 beta-HSD1, and 5 beta-reductase activity in hypertensive patients. Free urinary F, E, THF, and THE were measured by HPLC-MS/MS in 102 essential hypertensive patients and 18 normotensive controls. 11 beta-HSD2 enzyme activity was estimated by the F/E ratio, the activity of 11 beta-HSD1 in compare to 11 beta-HSD2 was inferred by the (5 alpha THF + 5 beta THF)/THE ratio and 5 beta-reductase activity assessed using the E/THE ratio. Activity was considered altered when respective ratios exceeded the maximum value observed in the normotensive controls. A 15.7% of patients presented high F/E ratio suggesting a deficit of 11 beta-HSD2 activity. Of the remaining 86 hypertensive patients, two possessed high (5 alpha THF + 5 beta THF)/THE ratios and 12.8% had high E/THE ratios. We observed a high percentage of alterations in cortisol metabolism at pre-receptor level in hypertensive patients, previously misclassified as essential. 11 beta-HSD2 and 5 beta-reductase decreased activity and imbalance of 11 beta-HSDs should be considered in the future management of hypertensive patients.
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    11β-hydroxysteroid dehydrogenase type 2 polymorphisms and activity in a Chilean essential hypertensive and normotensive cohort.
    (2012) Campino, Carmen; Quinteros, Hector; Owen, Gareth I.; Carvajal, Cristian A.; Morales, Mauricio; Olivieri, Oliviero; Guidi, Giancesare; Faccini, Giovanni; Pasini, Francesco; Baudrand, Rene; Padilla, Oslando; Valdivia, Carolina; Thichauer, Juan; Lagos, Carlos F.; Kalergis, Alexis M.; Fardella, Carlos E.
    BACKGROUND: 11β-hydroxysteroid dehydrogenase type 2 enzyme (11β-HSD2) inactivates cortisol (F) to cortisone (E); its impairment is associated with hypertension. We reported that 15.7% of the Chilean essential hypertensives possessed a high F/E ratio suggesting a partial deficit in 11β-HSD2 activity. It has been reported that the G534A(Glu178/Glu) polymorphism in the HSD11B2 gene is associated with hypertension. Investigate the frequency of the G534A polymorphism and its correlation with the glucocorticoid profile in Chilean essential hypertensive and normotensive subjects. METHODS: Essential hypertensive outpatients (n = 232) and normotensive subjects (n = 74) were recruited. A change in the AluI restriction enzyme digest pattern, caused by the presence of the G534A polymorphism, was utilized to screen DNA isolated from leukocytes within the cohort before confirmation by sequencing. Plasma renin activity (PRA), serum aldosterone, F, and E were measured by radioimmunoassay. Urinary tetrahydrocortisol (THF), 5α-tetrahydrocortisol (5α-THF), and tetrahydrocortisone (THE) were measured by gas chromatography-mass spectrometry. RESULTS: G534A polymorphism frequency was similar between hypertensive patients (19 of 232; 8.2%) and normotensive subjects (7 of 74; 9.5%). When categorized by presence or absence of the G534A polymorphism, no significant differences in the serum F/E ratio or other measured biochemical variables were detected. Despite a previous report that the G534A polymorphism is associated with a neighboring C468A (Thr156/Thr) polymorphism, analysis within our cohort showed that only one patient in each group presented with this double polymorphism. CONCLUSIONS: We report the frequency of the G534A polymorphism in the Spanish-Amerindian population. No correlation was detected between this polymorphism and the presence of hypertension and biochemical parameters in this Chilean cohort.
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    Administration of angiotensin II and a bradykinin B2 receptor blocker in midpregnancy impairs gestational outcome in guinea pigs
    (2014) Valdés Stromilli, Gloria; Schneider, Daniela; Corthorn H., Jenny; Ortíz, Rita; Acuña, Stephanie; Padilla, Oslando
    Abstract Background The opposing renin-angiotensin system (RAS) and kallikrein-kinin system (KKS) are upregulated in pregnancy and localize in the utero-placental unit. To test their participation as counter-regulators, circulating angiotensin II (AII) was exogenously elevated and the bradykinin B2 receptor (B2R) was antagonized in pregnant guinea-pigs. We hypothesized that disrupting the RAS/KKS balance during the period of maximal trophoblast invasion and placental development would provoke increased blood pressure, defective trophoblast invasion and a preeclampsia-like syndrome. Methods Pregnant guinea-pigs received subcutaneous infusions of AII (200 μg/kg/day), the B2R antagonist Bradyzide (BDZ; 62.5 microg/kg/day), or both (AII + BDZ) from gestational day 20 to 34. Non-pregnant cycling animals were included in a control group (C NP) or received AII + BDZ (AII + BDZ NP) during 14 days. Systolic blood pressure was determined during cycle in C NP, and on the last day of infusion, and 6 and 26 days thereafter in the remaining groups. Twenty six days after the infusions blood and urine were extracted, fetuses, placentas and kidneys were weighed, and trophoblast invasion of spiral arteries was defined in the utero-placental units by immunocytochemistry. Results Systolic blood pressure transiently rose in a subgroup of the pregnant females while receiving AII + BDZ infusion, but not in AII + BDZ NP. Plasma creatinine was higher in AII- and BDZ-treated dams, but no proteinuria or hyperuricemia were observed. Kidney weight increased in AII + BDZ-treated pregnant and non-pregnant females. Aborted and dead fetuses were increased in dams that received AII and AII + BDZ. The fetal/placental weight ratio was reduced in litters of AII + BDZ-treated mothers. All groups that received interventions during pregnancy showed reduced replacement of endothelial cells by extravillous trophoblasts in lateral and myometrial spiral arteries. Conclusions The acute effects on fetal viability, and the persistently impaired renal/placental sufficiency and incomplete arterial remodeling implicate the RAS and KKS in the adaptations in pregnancy. The results partially confirm our hypothesis, as a preeclampsia-like syndrome was not induced. We demonstrate the feasibility of characterizing systemic and local modifications in pregnant guinea-pig, supporting its use to study normal placentation and related disorders.Abstract Background The opposing renin-angiotensin system (RAS) and kallikrein-kinin system (KKS) are upregulated in pregnancy and localize in the utero-placental unit. To test their participation as counter-regulators, circulating angiotensin II (AII) was exogenously elevated and the bradykinin B2 receptor (B2R) was antagonized in pregnant guinea-pigs. We hypothesized that disrupting the RAS/KKS balance during the period of maximal trophoblast invasion and placental development would provoke increased blood pressure, defective trophoblast invasion and a preeclampsia-like syndrome. Methods Pregnant guinea-pigs received subcutaneous infusions of AII (200 μg/kg/day), the B2R antagonist Bradyzide (BDZ; 62.5 microg/kg/day), or both (AII + BDZ) from gestational day 20 to 34. Non-pregnant cycling animals were included in a control group (C NP) or received AII + BDZ (AII + BDZ NP) during 14 days. Systolic blood pressure was determined during cycle in C NP, and on the last day of infusion, and 6 and 26 days thereafter in the remaining groups. Twenty six days after the infusions blood and urine were extracted, fetuses, placentas and kidneys were weighed, and trophoblast invasion of spiral arteries was defined in the utero-placental units by immunocytochemistry. Results Systolic blood pressure transiently rose in a subgroup of the pregnant females while receiving AII + BDZ infusion, but not in AII + BDZ NP. Plasma creatinine was higher in AII- and BDZ-treated dams, but no proteinuria or hyperuricemia were observed. Kidney weight increased in AII + BDZ-treated pregnant and non-pregnant females. Aborted and dead fetuses were increased in dams that received AII and AII + BDZ. The fetal/placental weight ratio was reduced in litters of AII + BDZ-treated mothers. All groups that received interventions during pregnancy showed reduced replacement of endothelial cells by extravillous trophoblasts in lateral and myometrial spiral arteries. Conclusions The acute effects on fetal viability, and the persistently impaired renal/placental sufficiency and incomplete arterial remodeling implicate the RAS and KKS in the adaptations in pregnancy. The results partially confirm our hypothesis, as a preeclampsia-like syndrome was not induced. We demonstrate the feasibility of characterizing systemic and local modifications in pregnant guinea-pig, supporting its use to study normal placentation and related disorders.
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    Análisis psicométrico del cuestionario DREEM para medir el ambiente de aprendizaje en Chile.
    (2015) Herrera R., Cristian; Padilla, Oslando; Solís, Nancy; Pizarro Rojas, Margarita Alicia; Kattan Tala, Eduardo José; Díaz P., Luis Antonio; Riquelme Pérez, Arnoldo
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    Association of Remote Hypertension in Pregnancy With Coronary Artery Disease A Case-Control Study
    (LIPPINCOTT WILLIAMS & WILKINS, 2009) Valdes, Gloria; Quezada, Felipe; Marchant, Eugenio; von Schultzendorff, Astrid; Moran, Sergio; Padilla, Oslando; Martinez, Alejandro
    Because hypertensive pregnancies have been associated with increased cardiovascular disease, we aimed to identify whether angiographically characterized coronary artery disease differed in women with previous normotensive pregnancies or hypertensive pregnancies (HPs). The study group included 217 parous women, aged 60.9 +/- 9.2 (SD) years, who required coronary angiography between January 2006 and December 2007, 36.8 +/- 9.9 and 28.8 +/- 10.5 years after their first and last pregnancy, respectively; 146 had normotensive pregnancies and 71 had >= 1 HP, according to a questionnaire including reproductive history and cardiovascular risks. Body mass index, smoking, and frequency of diabetes were similar in both groups. Chronic hypertension (93% versus 78%; P=0.007), hyperlipidemia (82% versus 69%; P=0.049), and premature familial cardiovascular disease (42% versus 20%; P=0.001) prevailed in HPs. Participants with HPs were younger (58.9 +/- 8.3 versus 61.9 +/- 9.6 years; P=0.025) than participants with normotensive pregnancies. Although 49% of all participants had hemodynamically significant coronary artery disease (>= 70% stenosis), no differences were observed between groups in the number of stenotic arteries; however, their number increased by 28% and 22% over a 10-year period in HPs and normotensive pregnancies, respectively (P=0.034). Multivariate analysis showed that HPs had a nonsignificant risk of having coronary artery disease (odds ratio: 1.21; 95% CI: 0.64 to 2.28), and being a current smoker (odds ratio: 4.13; 95% CI: 1.85 to 9.25), a diabetic (odds ratio: 2.29; 95% CI: 1.85 to 9.25), or having a family history of premature cardiovascular disease (odds ratio: 2.34; 95% CI: 1.17 to 2.39) significantly increased the risk of coronary artery disease. This study demonstrates that women with HPs have earlier coronary disease, probably related to intermediate cardiovascular risks that have a gestational expression. (Hypertension. 2009; 53: 733-738.)
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    Benefit of adjuvant 5-fluorouracil based chemotherapy for colon cancer: a retrospective cohort study
    (SOC MEDICA SANTIAGO, 2016) Mondaca, Sebastian; Villalon, Constanza; Luis Leal, Jose; Zuniga, Alvaro; Bellolio, Felipe; Padilla, Oslando; Palma, Silvia; Garrido, Marcelo; Nervi, Bruno
    Background: Multiple clinical trials have demonstrated the benefits of adjuvant 5-fluorouracil-based chemotherapy for patients with resectable colon cancer (CC), especially in stage III. Aim: To describe the clinical characteristics of a cohort of CC patients treated at a single university hospital in Chile since 2002, and to investigate if chemotherapy had an effect on survival rates. Material and Methods: Review of a tumor registry of the hospital. Medical records of patients with CC treated between 2002 and 2012 were reviewed. Death certificates from the National Identification Service were used to determine mortality. Overall survival was described using the Kaplan-Meier method. A multivariate Cox proportional hazard regression model was also used. Results: A total of 370 patients were treated during the study period (202 in stage II and 168 in stage III). Adjuvant chemotherapy was administered to 22 and 70% of patients in stage II and III respectively. The median follow-up period was 4.6 years. The 5-year survival rate for stage II patients was 79% and there was no benefit observed with adjuvant chemotherapy. For stage III patients, the 5-year survival rate was 81% for patients who received adjuvant chemotherapy, compared to 56% for those who did not receive chemotherapy (hazard ratio (HR): 0.29; 95% confidence interval (CI): 0.15-0.56). The benefit of chemotherapy was found to persist after adjustment for other prognostic variables (HR: 0.47; 95% CI: 0.23-0.94). Conclusions: Patients with colon cancer in stage III who received adjuvant chemotherapy had a better overall survival.
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    CEACLIN, an instrument suited to identify medical students' strategies to learn in pre-clerkship years
    (SOC MEDICA SANTIAGO, 2015) Bitran, Marcela; Padilla, Oslando; Zuniga, Denisse; Leiva, Isabel; Calderon, Maribel; Riquelme, Arnoldo
    Background: Upon the beginning of pre-clerkship years, medical students must develop strategies to learn from experience and to improve their relational skills to communicate with patients. Aim: To develop an instrument to identify the strategies used by medical students to learn in clinical contexts. Material and Methods: Using a Delfi technique to reach consensus, a national panel of students and clinical teachers from 15 Chilean medical schools analyzed an 80-item questionnaire built from perceptions of Chilean students and teachers from one medical school. After two Delfi rounds and a pilot application, a 48-item questionnaire was obtained. Its reliability and construct validity were assessed by Cronbach alpha coefficient and factor analysis, respectively, on the base of an application to 336 medical students. Results: The questionnaire developed, named CEACLIN, is highly reliable (alpha = 0.84). Its inner structure is made of eleven factors: Autonomy, Solving doubts and problems, Searching and organizing information, Proactivity, Reaching to others, Paying attention and emotions, Searching for trust, Evading burden, Coping with burden, Motivation and Postponing the personal life. All together, these factors account for 47.4 % of the variance. Conclusions: CEACLIN is a valid, reliable and easy to use instrument suited to identify students' strategies to learn in pre-clerkship years. Many of its items allude to concepts of theories of experiential learning and motivation. We hope that CEACLIN will be of value to medical students and clinical teachers to improve the learning and teaching of clinical reasoning and communication skills.
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    Clot lysis time in platelet-rich plasma: Method assessment, comparison with assays in platelet-free and platelet-poor plasmas, and response to tranexamic acid
    (TAYLOR & FRANCIS INC, 2012) Panes, Olga; Padilla, Oslando; Matus, Valeria; Saez, Claudia G.; Berkovits, Alejandro; Pereira, Jaime; Mezzano, Diego
    Fibrinolysis dysfunctions cause bleeding or predisposition to thrombosis. Platelets contain several factors of the fibrinolytic system, which could up or down regulate this process. However, the temporal relationship and relative contributions of plasma and platelet components in clot lysis are mostly unknown. We developed a clot lysis time (CLT) assay in platelet-rich plasma (PRP-CLT, with and without stimulation) and compared it to a similar one in platelet-free plasma (PFP) and to another previously reported test in platelet-poor plasma (PPP). We also studied the differential effects of a single dose of tranexamic acid (TXA) on these tests in healthy subjects. PFP- and PPP-CLT were significantly shorter than PRP-CLT, and the three assays were highly correlated (p < 0.0001). PFP- and PPP-, but more significantly PRP-CLT, were positively correlated with age and plasma PAI-1, von Willebrand factor, fibrinogen, LDL-cholesterol, and triglycerides (p < 0.001). All these CLT assays had no significant correlations with platelet aggregation/secretion, platelet counts, and pro-coagulant tests to explore factor X activation by platelets, PRP clotting time, and thrombin generation in PRP. Among all the studied variables, PFP-CLT was independently associated with plasma PAI-1, LDL-cholesterol, and triglycerides and, additionally, stimulated PRP-CLT was also independently associated with plasma fibrinogen. A single 1 g dose of TXA strikingly prolonged all three CLTs, but in contrast to the results without the drug, the lysis times were substantially shorter in non-stimulated or stimulated PRP than in PFP and PPP. This standardized PRP-CLT may become a useful tool to study the role of platelets in clot resistance and lysis. Our results suggest that initially, the platelets enmeshed in the clot slow down the fibrinolysis process. However, the increased clot resistance to lysis induced by TXA is overcome earlier in platelet-rich clots than in PFP or PPP clots. This is likely explained by the display of platelet pro-fibrinolytic effects. Focused research is needed to disclose the mechanisms for the relationship between CLT and plasma cholesterol and its potential pathophysiologic and clinical relevance.
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    Development of ACLEEM questionnaire, an instrument measuring residents' educational environment in postgraduate ambulatory setting
    (2013) Riquelme Pérez, Arnoldo; Padilla, Oslando; Herrera, Cristián A.; Olivos, Trinidad; Román Brugnoli, José Antonio; Sarfatis Feige, Alberto; Torres, Patricio; Roff, Sue
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    Estrategias del aprendizaje inicial de la clínica: más allá de los hábitos de estudio. Percepciones de estudiantes y docentes clínicos
    (2015) Zúñiga Parada, Denisse Alejandra; Leiva Rodríguez, Isabel; Calderon, Maribel; Tomicic S., Alemka; Padilla, Oslando; Riquelme Pérez, Arnoldo; Bitrán Carreño, Marcela
    Background: Teaching methods of the undergraduate medical curriculum change considerably from the first years to clinical training. Clinical learning occurs in complex and varied scenarios while caring for patients. Students have to adapt their learning approaches and strategies to be able to integrate theory and clinical practice and become experiential learners. Aim: To identify the strategies used by medical students to learn during the initial clinical years, as reported by students themselves and by their clinical tutors. Material and Methods: We performed eight focus group discussions with 54 students enrolled in years three to six and we interviewed eight clinical tutors. Both focus group discussions and interviews were audio recorded, transcribed and analyzed according to Grounded Theory. Results: Four main themes were identified in the discourse of both students and tutors: Strategies oriented to theoretical learning, strategies oriented to experiential learning, strategies for integrating theory and practice and strategies oriented to evaluation. The mentioning of individual differences was present across the reports of both students and tutors. Conclusions: Students use a rich variety of strategies to face the challenges of clinical learning. Both students and tutors recognize that the learning approaches and strategies vary according the nature of the task and individual differences. The responses of students bring particular knowledge of the approaches used for the theoretical and practical integration and delve into the social dimension of learning.
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    Evaluación de docentes clínicos de Postgrado: desarrollo y propiedades psicométricas del instrumento MEDUC-PG14
    (2015) Pizarro Rojas, Margarita Alicia; Solís, Nancy; Rojas, Viviana; Díaz, Luis Antonio; Padilla, Oslando; Letelier Saavedra, Luz María; Aizman, Andrés; Sarfatis Feige, Alberto; Olivos, Trinidad; Soza, Alejandro; Delfino, Alejandro; Latorre, Gonzalo; Ivanovic-Zuvic, Danisa; Hoyl, Trinidad; Bitrán Carreño, Marcela; Arab Verdugo, Juan Pablo; Riquelme Pérez, Arnoldo; Pizarro, Margarita; Solís, Nancy; Rojas, Viviana; Díaz, Luis Antonio; Padilla, Oslando; Letelier Saavedra, Luz María; Aizman, Andrés; Sarfatis Feige, Alberto; Olivos, Trinidad; Soza, Alejandro; Delfino, Alejandro; Latorre, Gonzalo; Ivanovic-Zuvic, Danisa; Hoyl, Trinidad; Bitrán Carreño, Marcela; Arab Verdugo, Juan Pablo; Riquelme Pérez, Arnoldo
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    Evaluation of the educational environment in medical specialty programs
    (SOC MEDICA SANTIAGO, 2012) Herrera, Cristian A.; Olivos, Trinidad; Roman, Jose Antonio; Larrain, Antonia; Pizarro, Margarita; Solis, Nancy; Sarfatis, Alberto; Torres, Patricio; Padilla, Oslando; Le Roy, Catalina; Riquelme, Arnoldo
    Background: The Postgraduate Hospital Education Environment Measure (PHEEM) questionnaire, is a valid and reliable instrument to measure the educational environment (EE) in postgraduate medical education. Aim: To evaluate the EE perceived by the residents of a postgraduate training program using the PHEEM. Material and Methods: The PHEEM was applied in 2010-2011 in 35 specialty programs. We calculated their individual results and compared means of both global and individual domain scores of the PHEEM, by gender, university of origin and nationality. Cronbach's alpha coefficients and D study (Generalizability theory) were performed for reliability. Results: Three hundred eighteen residents were surveyed (75.7% of the total universe). The mean score of the PHEEM was 105.09 +/- 22.46 (65.7% of the maximal score) which is considered a positive EE. The instrument is highly reliable (Cronbach's alpha = 0.934). The D study found that 15 subjects are required to obtain reliable results (G coefficient = 0.813). There were no significant differences between gender and university of origin. Foreigners evaluated better the EE than Chileans and racism was not perceived. The programs showed a safe physical environment and teachers with good clinical skills. The negative aspects perceived were a lack of information about working hours, insufficient academic counseling, and scanty time left for extracurricular activities. Conclusions: This questionnaire allowed us to identify positive aspects of the EE, and areas to be improved in the specialty programs. The PHEEM is a useful instrument to evaluate the EE in Spanish-speaking participants of medical specialty programs. (Rev Med Chile 2012; 140: 1554-1561).
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    Higher levels of insulin‐like growth factor‐1 in cord blood associate with risk of asthma at age 3
    (2023) Castro‐Rodríguez, José Antonio; Padilla, Oslando; Casanello, Paola; Forno, Erick
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    Human papillomavirus and Epstein-Barr virus infections in breast cancer from chile
    (2011) Padilla, Oslando; Solís, Luisa.; Corvalán R., Alejandro; Aguayo González, Francisco; Khan, Noureen.; Koriyama, Chihaya.; González, Carolina; Ampuero, Sandra.; Eizuru, Yoshito.; Akiba, Suminori.
    Abstract Background Human papillomavirus (HPV) and Epstein Barr virus (EBV) have been found in breast carcinomas (BCs) around the world. In this study, fifty-five BCs from Chile were analyzed for HPV and EBV presence. In addition, HPV-16 viral load/physical status and E6/E7 expressions were determined. Results The amplification of a housekeeping gene showed that 46/55 samples (84%) had amplifiable DNA. HPV-16 was detected in 4/46 BCs (8.7%) and EBV was detected in 3/46 (6.5%) BCs. The analysis of HPV-16 physical status showed that this virus was integrated in all of the tumors with a relatively low viral load (range: 0.14 to 33.8 copies/cell). E6 and E7 transcripts, however, were not detected in any HPV-16 positive specimens. Using a Cox-regression model, we found a statistically significant association between EBV presence and poor survival (p = 0.013). Conclusions The findings in this study suggest that it is unlikely that HPV and/or EBV play a direct role in the etiology of BC.Abstract Background Human papillomavirus (HPV) and Epstein Barr virus (EBV) have been found in breast carcinomas (BCs) around the world. In this study, fifty-five BCs from Chile were analyzed for HPV and EBV presence. In addition, HPV-16 viral load/physical status and E6/E7 expressions were determined. Results The amplification of a housekeeping gene showed that 46/55 samples (84%) had amplifiable DNA. HPV-16 was detected in 4/46 BCs (8.7%) and EBV was detected in 3/46 (6.5%) BCs. The analysis of HPV-16 physical status showed that this virus was integrated in all of the tumors with a relatively low viral load (range: 0.14 to 33.8 copies/cell). E6 and E7 transcripts, however, were not detected in any HPV-16 positive specimens. Using a Cox-regression model, we found a statistically significant association between EBV presence and poor survival (p = 0.013). Conclusions The findings in this study suggest that it is unlikely that HPV and/or EBV play a direct role in the etiology of BC.
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    Identificación de las necesidades de capacitación docente de los jefes de programa de especialización médica
    (2013) Herrera Riquelme, Cristian Alberto; Niklitschek, Ian; Pizarro Rojas, Margarita Alicia; Solís, Nancy; Olivos, Trinidad; Rojas, Viviana; Etcheberry, Lorena; Rivera Besa, Horacio; Muñoz, Estrella; Bitrán Carreño, Marcela; Padilla, Oslando; Riquelme Pérez, Arnoldo
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    Incorporación de paciente virtual en portafolio de estudiantes de medicina de pregrado
    (2015) Figueroa, Catalina; Calvo, Ignacio; González, Carolina; Sandoval, Daniela; Padilla, Oslando; Le Roy, Catalina; Delfino, Alejandro; Arab Verdugo, Juan Pablo; Pizarro Rojas, Margarita Alicia; Solís, Nancy; Riquelme Pérez, Arnoldo
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    Knowdlege and preventive behaviors related to cervical cancer and human papiloma virus in a group of Chilean adolescents
    (SOC CHILENA INFECTOLOGIA, 2012) Teresa Urrutia, M.; Concha, Ximena; Riquelme, Giselle; Padilla, Oslando
    Knowdlege and preventive behaviors related to cervical cancer and human papiloma virus in a group of Chilean adolescents Introduction: The human papilloma virus (HPV) is a common sexually transmitted infection in young people and recognized as the most important risk factor for cervical cancer (CC). Aim: To describe the degree of knowledge that a group of Chilean teenagers have of HPV infection, CC, and its relationship with preventive behavior. Methods: This is an analytical study, with a random sample of 226 adolescents from three public schools of the Metropolitan Region in Santiago. Results: A fifth of the interviewed students did not know there was a HPV vaccine. Multiple sexual partners was indicated as a risk factor of CC by 70.8% and of HPV infection by 78.3% of them; while 60.3% identified inheritance as a risk factor. HPV transmission through unprotected sexual relations was identified by 68.2% of the sample. Of sexually active adolescents, condom use during sexual relations was reported by 31.1%. The adolescents who use condoms significantly have more knowledge regarding the number of sexual partners and age of first sexual intercourse as a risk factor for CC. Conclusion: adolescents know about HPV transmission, however, the preventing conducts are not related to this information.
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    Overexpression of 11 beta-hydroxysteroid dehydrogenase type 1 in visceral adipose tissue and portal hypercortisolism in non-alcoholic fatty liver disease
    (WILEY, 2012) Candia, Roberto; Riquelme, Arnoldo; Baudrand, Rene; Carvajal, Cristian A.; Morales, Mauricio; Solis, Nancy; Pizarro, Margarita; Escalona, Alex; Carrasco, Gonzalo; Boza, Camilo; Perez, Gustavo; Padilla, Oslando; Cerda, Jaime; Fardella, Carlos E.; Arrese, Marco
    Background: The enzyme 11 beta-hydroxysteroid-dehydrogenase type 1 (11 beta HSD1) catalyses the reactivation of intracellular cortisol. We explored the potential role of 11 beta-HSD1 overexpression in visceral adipose tissue (VAT) in non-alcoholic fatty liver disease (NAFLD) assessing sequential changes of enzyme expression, in hepatic and adipose tissue, and the occurrence of portal hypercortisolism in obese mice. 11 beta-HSD1 expression was also assessed in tissues from obese patients undergoing bariatric surgery. Methods: Peripheral and portal corticosterone levels and liver histology were assessed in ob/ob mice at two time points (8-12 weeks of age). 11 beta-HSD1 tissue expression was assessed in by RT-pcr in ob/ob mice and in 49 morbidly obese patients. Results: Portal corticosterone serum levels were higher in obese mice with a 26% decrease between 8 and 12 weeks of age (controls: 78.3 +/- 19.7 ng/ml, 8-week-old ob/ob: 167.5 +/- 14.5 ng/ml and 12-week-old ob/ob: 124.3 +/- 28 ng/ml, P < 0.05). No significant differences were found in peripheral corticosterone serum levels. Expression of 11b-HSD1 was lower in the liver [-45% at 8 weeks and -35% at 12-weeks (P = 0.0001)] and highly overexpressed in VAT in obese mice, compared to controls (128-fold higher in 8-week-old ob/ob and 41-fold higher in 12-week-old ob/ob, P < 0.01). No significant differences were seen in the expression of 11 beta-HSD1 in subcutaneous adipose tissue. In multivariate analysis, human 11 beta-HSD1 expression in VAT (OR: 1.385 +/- 1.010-1.910) was associated with NAFLD. Conclusion: Murine NAFLD is associated with portal hypercortisolism and 11 beta-HSD1 overexpression in VAT. In humans, 11 beta-HSD1 VAT expression was associated with the presence of NAFLD. Thus, local corticosteroid production in VAT may contribute to NAFLD pathogenesis.
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    Platelet count/spleen diameter ratio for non-invasive prediction of high risk esophageal varices in cirrhotic patients
    (ELSEVIER ESPANA, 2009) Barrera, Francisco; Riquelme, Arnoldo; Soza, Alejandro; Contreras, Alvaro; Barrios, Gerty; Padilla, Oslando; Viviani, Paola; Maria Perez Ayuso, Rosa
    Background and objective. Prophylaxis therapy is indicated in cirrhotic patients with large esophageal varices or small varices with red wale signs (high risk esophageal varices; HREV). Endoscopic surveillance to detect HREV is currently recommended. The objective of this study is to identify non-invasive predictors of HREV in cirrhotic patients. Design and methods. Adult cirrhotic patients without previous variceal bleeding were prospectively included. All patients underwent a complete biochemical workup, upper digestive endoscopy, and ultrasonographic measurement of spleen bipolar diameter. Platelet count/spleen diameter ratio (PC/SD) was calculated for all patients. The association of these variables with the presence of HREV in upper endoscopy was tested using univariate and multivariate analysis. Receiver operating characteristic (ROC) curves were constructed for variables associated with HREV. Results. Sixty-seven patients were included. The prevalence rate of HREV was 50%. Age, gender (female), platetet count, spleen diameter, PC/SD ratio, total bilirrubin, prothrombin activity (INR), Childl-Pugh score, clinical and ultrasonographic ascites were significantly associated with presence of HREV in univariate analysis. Age and PC/SD ratio were the parameters independently associated with HREV in a multivariate analysis, with OR 8.81 (CI 95%: 1.7-44.9) and OR 11.21 (CI 95%: 2.8-44.6) respectively. A PC/SD ratio cut-off value under 830.8 predicted HREV with 76.9% sensitivity, 74.2% specificity and 77.8% negative predictive value (ROC curve area: 0.78). Conclusions. The PC/SD ratio was significantly associated with HREV, but with suboptimal sensitivity and specificity. Therefore, the results of this study do not support the routine clinical use of PC/SD ratio for screening of HREV.
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    Psychometric analyses and internal consistency of the PHEEM questionnaire to measure the clinical learning environment in the clerkship of a Medical School in Chile
    (TAYLOR & FRANCIS LTD, 2009) Riquelme, Arnoldo; Herrera, Cristian; Aranis, Carolina; Oporto, Jorge; Padilla, Oslando
    Background and aims: The Spanish version of the Postgraduate Hospital Educational Environment Measure (PHEEM) was evaluated in this study to determine its psychometric properties, validity and internal consistency to measure the clinical learning environment in the hospital setting of Pontificia Universidad Catolica de Chile Medical School's Internship.