DSpace Angular :: Browsing by Author "Miquel Poblete, Juan Francisco"

Browsing by Author "Miquel Poblete, Juan Francisco"

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A Single-Nucleotide Polymorphism of (V3) Integrin Is Associated with the Andes Virus Infection Susceptibility
(2019) Martinez Valdebenito, Constanza Pamela; Angulo Troncoso Jenniffer Alexandra; Le Corre Pérez, Monique Nicole; Marco Caceres, Claudia Alejandra; Vial, Cecilia; Miquel Poblete, Juan Francisco; Cerda Lorca, Jaime Rodrigo; Mertz, Gregory; Vial, Pablo; Lopez Lastra, Marcelo Andres; Ferres Garrido, Marcela Viviana
Amerindian ancestry proportion as a risk factor for inflammatory bowel diseases: results from a Latin American Andean cohort
(2023) Pérez Jeldres, Tamara De Lourdes; Magne, Fabien; Ascui, Gabriel; Alvares, Danilo; Orellana, Matias; Álvarez Lobos Manuel Marcelo; Hernández Rocha, Cristián Antonio; Azocar, Lorena; Aguilar, Nataly; Espino, Alberto; Estela, Ricardo; Escobar, Sergio; Zazueta, Alejandra; Baez, Pablo; Silva, Veronica; de la Vega, Andres; Arriagada, Elizabeth; Pávez Ovalle, Carolina Denisse; Diaz-Asencio, Alejandro; Travisany, Dante; Miquel Poblete, Juan Francisco; Villablanca, Eduardo J.; Kronenberg, Mitchell; Bustamante, Maria Leonor
Background and aimsLatin American populations remain underrepresented in genetic studies of inflammatory bowel diseases (IBDs). Most genetic association studies of IBD rely on Caucasian, African, and Asian individuals. These associations have yet to be evaluated in detail in the Andean region of South America. We explored the contribution of IBD-reported genetic risk variants to a Chilean cohort and the ancestry contribution to IBD in this cohort.MethodsA total of 192 Chilean IBD patients were genotyped using Illumina's Global Screening Array. Genotype data were combined with similar information from 3,147 Chilean controls. The proportions of Aymara, African, European, and Mapuche ancestries were estimated using the software ADMIXTURE. We calculated the odds ratios (ORs) and 95% confidence intervals (CIs) for gender, age, and ancestry proportions. We also explored associations with previously reported IBD-risk variants independently and in conjunction with genetic ancestry.ResultsThe first and third quartiles of the proportion of Mapuche ancestry in IBD patients were 24.7 and 34.2%, respectively, and the corresponding OR was 2.30 (95%CI 1.52-3.48) for the lowest vs. the highest group. Only one variant (rs7210086) of the 180 reported IBD-risk SNPs was associated with IBD risk in the Chilean cohort (adjusted P = 0.01). This variant is related to myeloid cells.ConclusionThe type and proportion of Native American ancestry in Chileans seem to be associated with IBD risk. Variants associated with IBD risk in this Andean region were related to myeloid cells and the innate immune response.
Biliary aminopeptidase-N and the cholesterol crystallization defect in cholelithiasis
(British Medical Journal Publishing Group, 1995) Núñez, L.; Amigo Boker, Ludwig Peter; Mingrone, G.; Rigotti Rivera, Attilio Gianpietro; Puglielli, L.; Raddatz Echavarría, Alejandro; Pimentel González, Eduardo Fernando; Greco, A.; González, S.; Garrido Negri, Jorge; Miquel Poblete, Juan Francisco; Nervi Oddone, Flavio; Pontificia Universidad Católica de Chile. Departamento de Gastroenterología y Centro para la Prevención y tratamiento del Cáncer Digestivo; Institute of Clinical Medicine, Universita Cattolica del Sacro Cuore, Rome, Italy
Several biliary proteins have cholesterol crystallisation promoting activity. One of these glycoproteins is aminopeptidase-N, a canalicular ectoenzyme. This study attempted to localise aminopeptidase-N along the biliary tree, to assess its concentration in a series of 98 patients subjected to abdominal surgery, 40 of them without gap stones, and to correlate its concentration with cholesterol crystal formation time of gall bladder bile. Aminopeptidase-N was isolated from purified native biliary vesicles. A specific polyclonal rabbit anti-aminopeptidase-N antibody was prepared for quantitative immunoblotting and for immunolocalisation. Tissue was obtained from liver biopsy specimens and from gall bladders removed at surgery because of gall stone disease. Aminopeptidase-N was immunolocalised to the apical membranes of hepatocytes and to the apical pole of ductular and gall bladder mucosal cells. The nucleation time of gall bladder bile was mean (SD) 4 (3) days in the gall stone group, compared with 21 (18) days in the control group (p < 0.001). Total absolute biliary protein and aminopeptidase-N concentrations were similar in both the control and gall stone patients. There was a reciprocal significant correlation, however, between the nucleation time and the relative aminopeptidase-N concentration (r = -0.35, p < 0.01) only in the gall stone group of patients, This study shows that this apical transmembrane ectoenzyme with cholesterol crystallisation promoting activity is present along the biliary tree and the hepatocyte. These findings support the concept that high concentrations or qualitative changes of biliary aminopeptidase-N contribute to cholesterol gall stone formation.
Childhood cholelithiasis in a high prevalent population
(2007) Harris Diez, Paul Richard; Chateau Infante Bernardita; Miquel Poblete, Juan Francisco
Bile duct disease and gallstone (cholelithiasis) have been considered an uncommon cause of acute abdominal pain in children compared to adults. However, there are significant differences with the adult gallstone disease: increased proportion of patients with an underlying condition, higher incidence of acalculous cholecystitis and lower frequency of choledocolithiasis. With ultrasound examination, it is possible to detect early gallstone in the fetal period and in asymptomatic patients, explaining the increase in gallstone incidence. This disease is more common than suggested in western literature and its diagnosis is increasing as well. The high prevalence of gallstone in adult population in Chile creates an ideal setting for cholesterol and gallstone candidate gene testing. Although the clinical diagnosis of gallstone is simple, there is no consensus about the best therapy in children, explained partially by the lack of knowledge of the natural history of the disease. The role of gallstone disease acquired early in life in gallbladder carcinoma deserves special attention.
Diet as a risk factor for cholesterol gallstone disease
(2004) Cuevas Marín, Ada Marisa; Miquel Poblete, Juan Francisco; Reyes Soto, María Soledad; Zanlungo Matsuhiro, Silvana; Nervi Oddone, Flavio
Cholesterol gallstone disease is a common condition in western populations. The etiology is multifactorial with interaction of genetic and environmental factors. Obesity, aging, estrogen treatment, pregnancy and diabetes are consistently associated to a higher risk. A number of dietary factors have been involved in the pathogenesis of cholelithiasis. In this article we summarize several studies that have evaluated the role of diet as a potential risk factor for gallstone formation, including energy intake, cholesterol, fatty acids, fiber, carbohydrates, vitamins and minerals, and alcohol intake. Consumption of simple sugars and saturated fat has been mostly associated to a higher risk, while fiber intake and moderate consumption of alcohol, consistently reduce the risk. The association between cholesterol intake and gallstone disease has been variable in different studies. The effects of other dietary factors are less conclusive; additional studies are therefore necessary to clarify their relevance in the pathogenesis of gallstone disease. Recent discoveries of the role of orphan nuclear receptors in the regulation of fatty acid and hepatic cholesterol metabolism and excretion open new perspectives for a better understanding of the role of dietary constituents on cholesterol gallstone formation. KEY TEACHING POINTS: The etiology of cholesterol gallstone disease is multifactorial with interaction between genome and environment. It has been postulated that dietary constituents are important determinants for the formation of lithogenic bile. Intake of high energy, simple sugar and saturated fat favors gallstone formation. Fiber and moderate consumption of alcohol reduce the risk. The role of orphan nuclear receptors in the regulation of hepatic cholesterol metabolism and excretion open new leads for understanding the role of dietary constituents on cholesterol gallstone formation.
Diminishing benefits of urban living for children and adolescents' growth and development
(Nature Portfolio, 2023) Berrios Carrasola, Ximena; Echeverría Errázuriz, Guadalupe; Ferreccio Readi, Fresia Catterina; Margozzini Maira, Paula Andrea; Miquel Poblete, Juan Francisco; Nervi Oddone, Flavio; Rigotti Rivera, Attilio Gianpietro; Valdivia Cabrera, Gonzalo Sergio; Mishra, A.; Zhou, B.; Rodríguez-Martínez, A.; Bixby, H.; Singleton, R. K.; Carrillo-Larco, R. M.; Sheffer, K. E.; Paciorek, C. J.; Bennett, J. E.; Lhoste, V.; Lurilli, M. L.; Di Cesare, M.
Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1,2,3,4,5,6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.
Enfermedad vesicular inaparente o microlitiasis en pacientes con pancreatitis aguda: Una situación clínica frecuente
(1997) Miquel Poblete, Juan Francisco; Prado Sanhueza, María Alejandra; Asahi Kodama, Harumi Paz; Ibáñez Anrique, Luis Alberto; Guzmán Bondiek, Sergio; Cruz Olivos, Francisco; Rollan Rodríguez, Antonio Rafael; Nervi Oddone, Flavio
Background: Patients with acute pancreatitis (AP) and a normal gallbladder by standard echographic evaluation may have "occult" gallbladder disease or microlithiasis with recurrent episodes of AP. Aim: To conduct a prospective evaluation of patients with the diagnosis of non-biliary AP in order to detect "occult" gallbladder disease and to compare its clinical presentation with that of biliary AP. Patients and methods: Patients admitted with the diagnosis of AP to a clinical hospital were included in the study. According to an abdominal ultrasound study, patients were classified as having or not cholelithiasis. A duodenal biliary drainage was performed in 15 patients with AP and without gallbladder stones. Results: Patients without cholelithiasis had recurrent AP more often than patients with biliary AP (53 and 33% respectively). Excessive alcohol ingestion did not rule out the possibility of biliary etiology. In 6 patients, the analysis of duodenal bile showed cholesterol crystals, and cholecystectomy confirmed the existence of gallbladder disease in 5. All of them remained asymptomatic during a follow-up period of four years. One patient refused surgery, with subsequent development of gallstones and recurrent episodes of AP. In other 4 patients, gallbladder disease was confirmed by percutaneous gallbladder puncture or during cholecystectomy. No recurrence of AP were observed during the follow-up. Conclusions: Microlithiasis or "occult" gallbladder disease accounts for at least 67% of the original "non-biliary" AP. Duodenal bile analysis is a useful and necessary technique for the evaluation of patients with "non-biliary" acute pancreatitis'. Careful clinical and echographic follow-up of this subgroup of patients with AP is mandatory.
Epidemiology and Molecular Pathology of Gallbladder Cancer
(2001) Lazcano-Ponce, Eduardo; Miquel Poblete, Juan Francisco; Muñoz, Nubia; Herrero, Rolando; Ferrecio, Catterina; Wistuba Oyarzún, Ignacio; Alonso de Ruiz, Patricia; Aristi Urista, Gerardo; Nervi Oddone, Flavio
Gallbladder cancer is usually associated with gallstone disease, late diagnosis, unsatisfactory treatment, and poor prognosis, We report here the worldwide geographical distribution of gallbladder cancer, review the main etiologic hypotheses, and provide some comments on perspectives for prevention. The highest incidence rate of gallbladder cancer is found among populations of the Andean area, North American Indians, and Mexican Americans. Gallbladder cancer is up to three times higher among women than men in all populations. The highest incidence rates in Europe are found in Poland, the Czech Republic, and Slovakia. Incidence rates in other regions of the world are relatively low. The highest mortality rates are also reported from South America, 3.5-15.5 per 100,000 among Chilean Mapuche Indians, Bolivians, and Chilean Hispanics. Intermediate rates, 3.7 to 9.1 per 100,000, are reported from Peru, Ecuador, Colombia, and Brazil. Mortality rates are low in North America, with the exception of high rates among American Indians in New Mexico (11.3 per 100,000) and among Mexican Americans.", "The main associated risk factors identified so far include cholelithiasis (especially untreated chronic symptomatic gallstones), obesity, reproductive factors, chronic infections of the gallbladder, and environmental exposure to specific chemicals. These suspected factors likely represent promoters of carcinogenesis. The main limitations of epidemiologic studies on gallbladder cancer are the small sample sizes and specific problems in quantifying exposure to putative risk factors. The natural history of gallbladder disease should be characterized to support the allocation of more resources for early treatment of symptomatic gallbladder disease in high-risk populations. Secondary prevention of, gallbladder cancer could be effective if supported by cost-effective studies of prophylactic cholecystectomy among asymptomatic gallstone patients in high-risk areas."]
Ezetimibe prevents cholesterol gallstone formation in mice
(2008) Zuñiga, Silvia Eugenia; Molina, Héctor; Azócar, Lorena; Amigo Boker, Ludwig Peter; Nervi Oddone, Flavio; Pimentel Muller, Fernando Ernesto; Jarufe Cassis, Nicolas Patricio; Arrese Jimenez, Marco Antonio; Lammert, Frank; Miquel Poblete, Juan Francisco
Background: Intestinal cholesterol absorption may influence gallstone formation and its modulation could be a useful therapeutic strategy for gallstone disease (GSD). Ezetimibe (EZET) is a cholesterol-lowering agent that specifically inhibits intestinal cholesterol absorption. Aims: To test whether EZET can prevent gallstone formation in mice. Methods/Results: Gallstone-susceptible C57BL/6 inbred mice were fed control and lithogenic diets with or without simultaneous EZET administration. Lithogenic diet increased biliary cholesterol content and secretion, and induced sludge or gallstone formation in 100% of the animals. EZET administration reduced intestinal cholesterol absorption by 90% in control animals and by 35% in mice receiving the lithogenic diet. EZET prevented the appearance of cholesterol crystals and gallstones. In addition, mice fed the lithogenic diet plus EZET exhibited a 60% reduction in biliary cholesterol saturation index. Of note, EZET treatment caused a significant increase in bile flow (+50%, P < 0.01) as well as bile salt, phospholipid and glutathione secretion rates (+60%, +44% and +100%, respectively, P < 0.01), which was associated with a moderately increased expression of hepatic bile salt transporters. In addition, relative expression levels of Nieman-Pick C1 like 1 (NPC1L1) in the enterohepatic axis in humans were assessed. Expression levels of NPC1L1 were 15-to 30-fold higher in the duodenum compared with the liver at transcript and protein levels, respectively, suggesting preferential action of EZET on intestinal cholesterol absorption in humans. Conclusions: In a murine model of GSD, EZET prevented gallstone formation by reducing intestinal cholesterol absorption and increasing bile salt-dependent and -independent bile flow. EZET could be useful in preventing GSD disease in susceptible patients.
Flow studies on human GPVI-deficient blood under coagulating and noncoagulating conditions
(2020) Nagy, Magdolna; Perrella, Gina; Dalby, Amanda; Becerra Yañez, María Francisca Aurora del Car; García Quintanilla, Lourdes; Pike, Jeremy A.; Morgan, Neil V.; Gardiner, Elizabeth E.; Heemskerk, Johan W. M.; Azócar López, Lorena Karina; Miquel Poblete, Juan Francisco; Mezzano Abedrapo, Diego; Watson, Steve P.
The role of glycoprotein VI (GPVI) in platelets was investigated in 3 families bearing an insertion within the GP6 gene that introduces a premature stop codon prior to the transmembrane domain, leading to expression of a truncated protein in the cytoplasm devoid of the transmembrane region. Western blotting and flow cytometry of GP6(hom) (homozygous) platelets confirmed loss of the full protein. The level of the Fc receptor -gamma-chain, which associates with GPVI in the membrane, was partially reduced, but expression of other receptors and signaling proteins was not altered. Spreading of platelets on collagen and von Willebrand factor (which supports partial spreading) was abolished in GP6(hom) platelets, and spreading on uncoated glass was reduced. Anticoagulated whole blood flowed over immobilized collagen or a mixture of von Willebrand factor, laminin, and rhodocytin (noncollagen surface) generated stable platelet aggregates that express phosphatidylserine (PS). Both responses were blocked on the 2 surfaces in GP6(hom) individuals, but adhesion was not altered. Thrombin generation was partially reduced in GP6(hom) blood. The frequency of the GP6(het) (heterozygous) variant in a representative sample of the Chilean population (1212 donors) is 2.9%, indicating that there are similar to 4000 GP6(hom) individuals in Chile. These results demonstrate that GPVI supports aggregation and PS exposure under flow on collagen and noncollagen surfaces, but not adhesion. The retention of adhesion may contribute to the mild bleeding diathesis of GP6(hom) patients and account for why so few of the estimated 4000 GP6(hom) individuals in Chile have been identified.
Gallstone disease: From genes to evidence-based therapy
(2008) Lammert, Frank; Miquel Poblete, Juan Francisco
The number of gallstone patients is increasing in ageing populations with a high prevalence of metabolic syndrome and obesity. Recently variants of hepatic ATP binding cassette transporters have been identified as genetic susceptibility factors for gallstone disease, pointing to novel means for risk assessment and prevention. Although laparoscopic cholecystectomy is the mainstay of therapy for symptomatic gallbladder stones, the clinical management of gallstone disease is changing rapidly, with an increase in day case surgery and the advent of transluminal endoscopic surgery. Here, we summarize the molecular and genetic mechanisms of gallstone formation as well as the current evidence-based algorithms for diagnosis and therapy of gallbladder and bile duct stones. (c) 2008 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
Genetics of biliary lithiasis from an ethnic perspective
(2013) Krawczyk, Marcin; Miquel Poblete, Juan Francisco; Stokes, Caroline S.; Zuniga, Silvia; Hampe, Jochen; Mittal, Balraj; Lammert, Frank
Gallstone disease represents one of the most common gastroenterological disorders worldwide. Gallstones affect over 15% of adults in Europe and 25-30% of Hispanic populations in Central and South America. The heritability of gallstones varies considerably according to ethnicity, with Native Americans and Hispanics with Amerindian admixture being the most susceptible populations. Genetic factors have been shown to account for 25-30% of total gallstone risk in Europe, however, in Hispanic populations, this risk percentage may increase to 45-65%. Recent genome-wide association and candidate gene studies have identified common polymorphisms in enterohepatic transporters (ABCG5/8, SLC10A2) and the Gilbert syndrome UGT1A1 variant as genetic determinants of gallstone formation. Together, these polymorphisms cover a significant proportion of the previously predicted genetic background of gallstones in European populations. New lithogenic genes need to be discovered in future studies in high-risk populations. In this review, we address the latest developments in the genetic analysis of gallstones and discuss the ethnic background of this condition in European, Central and South American and Asian populations. (C) 2012 Elsevier Masson SAS. All rights reserved.
Genotype Prevalence of Lactose Deficiency, Vitamin D Deficiency, and the Vitamin D Receptor in a Chilean Inflammatory Bowel Disease Cohort: Insights from an Observational Study
(MDPI, 2023) Pérez Jeldres, Tamara De Lourdes; Bustamante, M. Leonor; Segovia-Melero, Roberto; Aguilar, Nataly; Magne, Fabien; Ascui, Gabriel; Uribe, Denisse; Azocar, Lorena; Hernández Rocha, Cristián Antonio; Estela, Ricardo; Silva, Veronica; De La Vega, Andres; Arriagada, Elizabeth; Gonzalez, Mauricio; Onetto, Gian-Franco; Escobar, Sergio; Baez, Pablo; Zazueta, Alejandra; Pávez Ovalle Carolina Denisse; Miquel Poblete, Juan Francisco; Álvarez Lobos Manuel Marcelo
Lactose intolerance (LI) and vitamin D deficiency (VDD) have been linked to inflammatory bowel disease (IBD). We conducted an observational study in 192 Chilean IBD patients to investigate the prevalence of a specific gene variant (LCT-13910 CC genotype) associated with LI and the prevalence of VDD/Vitamin D Receptor (VDR) gene variants. Blood samples were analyzed using Illumina's Infinium Global Screening Array. The LCT-13910 CC genotype was found in 61% of IBD patients, similar to Chilean Hispanic controls and lower than Chilean Amerindian controls. The frequency of the LCT-13910-C allele in Chilean IBD patients (0.79) was comparable to the general population and higher than Europeans (0.49). Regarding VDR and VDD variants, in our study, the rs12785878-GG variant was associated with an increased risk of IBD (OR = 2.64, CI = 1.61-4.32; p-value = 0.001). Sixty-one percent of the Chilean IBD cohort have a genetic predisposition to lactose malabsorption, and a significant proportion exhibit genetic variants associated with VDD/VDR. Screening for LI and VDD is crucial in this Latin American IBD population.
HDL receptor SR-BI and cholesterol gallstones
(2002) Rigotti Rivera, Attilio Gianpietro; Miquel Poblete, Juan Francisco; Wang DQH; Zanlungo S
Hepatitis autoinmune en una escolar asociada a la presencia de anticuerpos anti-LKM
(1997) Larraín Barros, Francisco Javier; Miquel Poblete, Juan Francisco; González Bombardiere, Sergio
Autoimmune hepatitis is an inflammatory liver disease characterized by dense mononuclear cell infiltrate in the portal tract, and serologically by the presence of non-organ and liver-specific autoantibodies and increased levels of gammaglobulins in the absence of a known etiology. Three subgroups of autoimmune hepatitis have been recognized, depending on the nature of the autoantibody present in the serum: Type 1 autoimmune hepatitis, associated with smooth-muscle (SMA) or antinuclear antibody (ANA) seropositivity; type 2, with anti-liver/kidney microsome antibody (anti-LKM1), and type 3, with the absence of ANA, SMA and anti-LKM1 and presence of other autoantibodies such as anti-soluble liver antigen (SLA). Subtypes of chronic autoimmune hepatitis have clinically different features and prognoses. An 8 year old female patient presented mild jaundice of insidious onset. The liver was tender and enlarged. Serologic markers for A, B, C, E, Epstein Barr and citomegalovirus were negative. The liver biopsy showed a histological picture consistent with chronic active hepatitis. High titers of anti-liver/kidney-microsome antibody were found by indirect immunofluorescence test, and this finding was confirmed by Western blot against specific liver microsome antigens. Therapy with prednisolone induced a clinical and biochemical remision after four weeks. The suspension of therapy under strict medical control produced a rapid relapse of clinical and biochemical features. The reinitiation of prednisolone was successful, and alternate-day program was started and maintained until 8 months follow-up.
Heterogeneous contribution of microdeletions in the development of common generalized and focal epilepsies
(2017) Pérez-Palma, E.; Helbig, I.; Klein, K.M.; Anttila, V.; Horn, H.; Reinthaler, E.M.; Gormley, P.; Ganna, A.; Byrnes, A.; Pernhorst, K.; Toliat, M.R.; Saarentaus, E.; Howrigan, D.P.; Hoffman, P.; Miquel Poblete, Juan Francisco; de Ferrari, G.; Nürnberg, P.; Lerche, H.; Zimprich, F.; Neubauer, B.A.; Becker, A.J.; Rosenow, F.; Perucca, E.; Zara, F.; Weber, Y.G.; Lal, D.
Background: Microdeletions are known to confer risk to epilepsy, particularly at genomic rearrangement “hotspot” loci. However, deciphering their role outside hotspots and risk assessment by epilepsy sub-type has not been conducted. Methods: We assessed the burden, frequency and genomic content of rare, large microdeletions found in a previously published cohort of 1,366 patients with Genetic Generalized Epilepsy (GGE) plus two sets of additional unpublished genomewide microdeletions found in 281 Rolandic Epilepsy (RE) and 807 Adult Focal Epilepsy (AFE) patients, totaling 2,454 cases. These microdeletion sets were assessed in a combined analysis and in sub-type specific approaches against 6,746 ethnically matched controls. Results: When hotspots are considered, we detected an enrichment of microdeletions in the combined epilepsy analysis (adjusted-P= 2.00x10-7; OR = 1.89; 95%-CI: 1.51-2.35), where the implicated microdeletions overlapped with rarely deleted genes and those involved in neurodevelopmental processes. Subtype specific analyses showed that hotspot deletions in the GGE subgroup contribute most of the signal (adjusted-P = 1.22x10-12; OR = 7.45; 95%-CI = 4.20-11.97). Outside hotspot loci, microdeletions were enriched in the GGE cohort for neurodevelopmental genes (adjusted-P = 4.78x10-3; OR = 2.30; 95%-CI = 1.42-3.70), whereas no additional signal was observed for RE and AFE. Still, gene content analysis was able to identify known (NRXN1, RBFOX1 and PCDH7) and novel (LOC102723362) candidate genes affected in more than one epilepsy sub-type but not in controls. Conclusions: Our results show a heterogeneous effect of recurrent and non-recurrent microdeletions as part of the genetic architecture of GGE and a minor to negligible contribution in the etiology of RE and AFE.
Impaired biliary cholesterol secretion and decreased gallstone formation in apolipoprotein E-deficient mice fed a high-cholesterol diet
(2000) Amigo Boker, Ludwig Peter; Quiñones, Verónica; Mardones, Pablo; Zanlungo Matsuhiro, Silvana; Miquel Poblete, Juan Francisco; Nervi Oddone, Flavio; Rigotti Rivera, Attilio Gianpietro
Background & aimsBecause apolipoprotein E (apoE) is a key cholesterol transport molecule involved in the hepatic uptake of chylomicron cholesterol, it may play a critical role in controlling bile cholesterol elimination and cholesterol gallstone formation induced by dietary cholesterol. To test this hypothesis, we studied biliary lipid secretion and gallstone formation in apoE-deficient mice fed cholesterol-rich diets.MethodsBile lipid outputs and gallstone sequence events were analyzed in apoE-deficient mice fed a high-cholesterol diet or a lithogenic diet compared with control animals.ResultsA high-cholesterol diet increased biliary cholesterol secretion and gallbladder bile cholesterol concentration in wild-type mice; the increase in bile cholesterol secretion was significantly attenuated in apoE-deficient mice. ApoE knockout mice fed a high-cholesterol lithogenic diet had a markedly lower frequency of gallbladder bile cholesterol crystal and gallstone formation than wild-type mice, which was most likely a result of the decreased cholesterol saturation index found in gallbladder bile of apoE-deficient mice.ConclusionsThese results show that apoE expression is an important factor for regulating both biliary secretion of diet-derived cholesterol as well as diet-induced cholesterol gallstone formation in mice.
Infarto encefálico por embolia aérea. Caso clínico
(2005) Mellado Talesnik, Patricio Andrés; Constanzo Parra, Freddy Mauricio; Miquel Poblete, Juan Francisco; Ibáñez Lazo, Patricio Fernando
Ishemic stroke due to embolic air is uncommon. There are few reports of patients with air embolic stroke as a complication of endoscopic procedures. The temporal relationship between the stroke and this procedure is the most important clue for the diagnosis. CT scan and MRI of the brain are confirmatory tests. The morbidity and mortality is high. Patients should be hospitalizedin a critical care service and treated as soon as possible with oxygen in a pressure camera. We report a 52 years old woman with an ovarian cancer that, during an upper gastrointestinal endoscopy, had a severe alteration of consciousness that did not respond to the use of Flumazenil. A CT scan showed multiple areas of air embolism in the watershed are between anterior and middle right cerebral arteries. A conservative treatment was decided and the patients died 48 hours later.
Microlithiasis and cholesterolosis in idiopathic acute pancreatitis
(W. B. Saunders Co., 1992) Miquel Poblete, Juan Francisco; Rollan Rodríguez, Antonio Rafael; Guzmán Bondiek, Sergio; Nervi Oddone, Flavio
Paths and timings of the peopling of Polynesia inferred from genomic networks
(2021) Ioannidis, Alexander G.; Blanco Portillo, Javier; Sandoval, Karla; Hagelberg, Erika; Barberena Jonas, Carmina; Hill, Adrian V. S.; Rodriguez Rodriguez, Juan Esteban; Fox, Keolu; Robson, Kathryn; Haoa Cardinali, Sonia; Quinto Cortes, Consuelo D.; Miquel Poblete, Juan Francisco; Auckland, Kathryn; Parks, Tom; Sofro, Abdul Salam M.; Ávila Arcos, Maria C.; Sockell, Alexandra; Homburger, Julian R.; Eng, Celeste; Huntsman, Scott; Burchard, Esteban G.; Gignoux, Christopher R.; Verdugo, Ricardo A.; Moraga, Mauricio; Bustamante, Carlos D.; Mentzer, Alexander J.; Moreno Estrada, Andrés
Polynesia was settled in a series of extraordinary voyages across an ocean spanning one third of the Earth(1), but the sequences of islands settled remain unknown and their timings disputed. Currently, several centuries separate the dates suggested by different archaeological surveys(2-4). Here, using genome-wide data from merely 430 modern individuals from 21 key Pacific island populations and novel ancestry-specific computational analyses, we unravel the detailed genetic history of this vast, dispersed island network. Our reconstruction of the branching Polynesian migration sequence reveals a serial founder expansion, characterized by directional loss of variants, that originated in Samoa and spread first through the Cook Islands (Rarotonga), then to the Society (Totaiete ma) Islands (11th century), the western Austral (Tuha'a Pae) Islands and Tuamotu Archipelago (12th century), and finally to the widely separated, but genetically connected, megalithic statue-building cultures of the Marquesas (Te Henua 'Enana) Islands in the north, Raivavae in the south, and Easter Island (Rapa Nui), the easternmost of the Polynesian islands, settled in approximately ad 1200 via Mangareva.

Browsing by Author "Miquel Poblete, Juan Francisco"

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