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1.
Alejandra Gordillo Hernández Eduardo Dominguez-Adame Lanuza Auxiliadora Cano Matias Rosario Perez Huertas Katherine Maria Gallardo Rodriguez Purificacion Gallinato Perez Fernando Oliva Mompean 《World journal of gastrointestinal surgery》2015,7(8):170-173
Gangliocytic paragangliomas are rare tumors that almost exclusively occur within the second portion of the duodenum. Although these tumors generally have a benign clinical course, they have the potential to recur or metastasize to regional lymph nodes. The case report presented here describes a 57-year-old female patient with melena, progressive asthenia, anemia, and a mass in the second-third portion of the duodenum that was treated by local excision. The patient was diagnosed with a friable bleeding tumor. The histologic analysis showed that the tumor was a 4 cm gangliocytic paraganglioma without a malignant cell pattern. In the absence of local invasion or distant metastasis, endoscopic resection represents a feasible, curative therapy. Although endoscopic polypectomy is currently considered the treatment of choice, it is not recommended if the size of the tumor is > 3 cm and/or there is active or recent bleeding. Patients diagnosed with a gangliocytic paraganglioma should be closely followed-up for possible local recurrence. 相似文献
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Histological study of the proximal and distal segments of the embryonic outflow tract and great arteries 总被引:1,自引:0,他引:1
Sánchez Gómez C Pliego Pliego L Contreras Ramos A Angel Munguía Rosas M Salazar García M García Romero HL González Jiménez MA 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,283(1):202-211
The normal development of the ventricular outlets and proximal region of the great arteries is a controversial subject. It is known that the conus, truncus arteriosus (truncus), and aortic sac participate; however, there are some doubts as to the actual prospective fate of the truncus. Some authors propose that it gives origin to the proximal region of the great arteries and that the myocardial cells of its wall become smooth muscle. Nevertheless, others think that the truncus only forms the arterial valve apparatus and that therefore the myocardial cells transform into fibroblasts. As a first approach to beginning to elucidate which process occurs, the aim of this article was to study the histological changes in the wall of these components of the developing heart in chick embryos whose hearts had been labeled at the truncoconal boundary at stage 22HH, tracing the changes up to stage 36HH. Also, the histological constitution of the wall of the pulmonary arterial trunk and its valve apparatus were studied in the posthatching and adult hearts of chickens and rats. The conus and truncus walls were always encircled by a myocardial sleeve from the outset of their development. Between stages 26HH to 28HH, the truncal myocardial cells adjacent to the mesenchymal tissue of the ridges began to lose cell-to-cell contacts and invaded the extracellular matrix. At stage 24HH, the aortic sac began to project into the pericardial cavity and became divided into two channels by the aortic-pulmonary septum at stage 26HH. The wall of the aortic sac is mostly constituted by a compact mesenchymal tissue. Initially, it does not have smooth muscle but this starts to appear at stage 30HH. The insertion ring of the valves, a broad structure, was formed by mesenchymal tissue. Both structures were always covered by a myocardial sleeve. The leaflets developed from the truncal ridges, the segment immediately proximal to the aortic sac. Our results indicate that the proximal region of the pulmonary and aortic arteries do not originate from the truncus arteriosus; rather, we found that they take origin from the aortic sac. Thus, our findings agree with the proposal that the myocardial cells of the external sleeve of the truncus become fibroblastic and suggest that the insertion ring of the arterial valves has a dual origin: fibroblasts produced by truncal myocardial transdiferentiation and the mesenchymal tissue of the proximal region of the truncal ridges, while the leaflets have their origin from the truncal ridges. We discuss the fact that, because the truncus arteriosus does not give origin to the trunks of the aortic and pulmonary arteries, it may be necessary to modify terminology. Based on our results, together with the new findings obtained by in vivo labeling, immunostaining, a chimeric approach, and ultrastructural studies, we propose a developmental model that correlates the fate of the conus, truncus, and aortic sac with the normal morphogenesis of the ventricular outlet tracts and the trunks of the great arteries. (c) 2005 Wiley-Liss, Inc. 相似文献
4.
Bone-specific antibodies in sera from patients with celiac disease: characterization and implications in osteoporosis 总被引:5,自引:0,他引:5
Sugai E Cherñavsky A Pedreira S Smecuol E Vazquez H Niveloni S Mazure R Mauriro E Rabinovich GA Bai JC 《Journal of clinical immunology》2002,22(6):353-362
Osteopenia and osteoporosis are well-known complications detected in celiac disease patients with still obscure pathogenesis. In the present study we investigated the presence of circulating anti-bone autoantibodies in patients with celiac disease and explored their role in the associated bone disease. We evaluated serum samples from 33 patients at the time of diagnosis and from 20 of them after treatment. Sera from patients with inflammatory bowel disease (n = 9), nonceliac osteoporotic (n = 18), and healthy individuals (n = 10) were used as controls. The presence of IgA specific anti-bone antibodies was first investigated using indirect immunofluorescence on cryosections of fetal rat tibia (20-day pregnancy). Furthermore, samples were homogenized and total tissue extracts were subjected to Western blot analysis to confirm immunoreactivity. At diagnosis, sera from 51.5% (17/33) of celiac patients had antibodies that recognized antigenic structures in chondrocytes and the extracellular matrix along mature cartilage, bone interface, and perichondrium of fetal rat bone. Among controls, only two osteoporotic patients showed very low titles of anti-bone autoantibodies. The immunostaining was localized in areas where an active mineralization process occurred and was similar to the distribution of the native bone tissue transglutaminase. The frequency of patients with positive baseline titers of anti-bone antibodies diminished significantly after treatment (P = 0.048). Western blot assays confirmed the presence of autoantibodies in sera from patients with a positive immunofluorescence staining. Autoantibodies recognized a major protein band on tissue extracts with a molecular weight of 77–80 kDa, which could be displaced when sera were preadsorbed with human recombinant tissue transglutaminase. We provide original evidence that patients with celiac disease have IgA-type circulating autoantibodies against intra- and extracellular structures of fetal rat tibia. Our findings suggest that these antibodies recognize bone tissue transglutaminase as the autoantigen, and based on the localization of the immunoreactivity we speculate that they might have an active role in the pathophysiology of celiac disease-associated bone complications. 相似文献
5.
Alejandra María Corona-Romero María Fernanda Bernal-Orozco Gabriela Alejandra Grover-Baltazar Barbara Vizmanos 《Nutrients》2021,13(6)
Childhood obesity and children being overweight has increased recently; although they are multi-causal problems, an unhealthy diet is a critical component. In Mexico, drinking water consumption in children from 9 to 18 years only reaches 30% of total fluid consumption. The aim of our study was to describe the social representations (SR) of drinking water in school-children and parents of two schools in Zapopan, Mexico. Associative free listing was used as an information gathering technique. Schoolchildren aged 8 to 12 years (n = 50) and parents (n = 23) from two elementary schools were selected by a convenience sampling from April to June 2015. A similarity analysis was performed using the co-occurrence index; with this, a similarity graph was obtained. Prototypical analysis was performed to explore the structure of the SR. Three dimensions were described in the children’s SR: a functional dimension related to health and nutrition, a practical dimension that describes the instruments used for its consumption, and a theoretical dimension that specifies the characteristics of water and its relationship with nature. In the parents’ SR, a functional dimension was also found; another dimension was described regarding the integral well-being that drinking water provides. A practical dimension describes the features related to its consumption. The investigation describes the structure of the water SR, which help to contextualize and explain the actions of schoolchildren and their parents regarding drinking water consumption. 相似文献
6.
Karla MacDonald-Ramos Alejandra Martínez-Ibarra Adriana Monroy Juan Miranda-Ríos Marco Cerbn 《Nutrients》2021,13(6)
Dietary fatty acids (DFAs) play key roles in different metabolic processes in humans and other mammals. DFAs have been considered beneficial for health, particularly polyunsaturated (PUFAs) and monounsaturated fatty acids (MUFAs). Additionally, microRNAs (miRNAs) exert their function on DFA metabolism by modulating gene expression, and have drawn great attention for their potential as biomarkers and therapeutic targets. This review explicitly examined the effects of DFAs on miRNA expression associated with metabolic diseases, such as obesity, non-alcoholic fatty liver disease (NAFLD), and cardiovascular disease (CVD), as well as inflammation, published in the last ten years. DFAs have been shown to induce and repress miRNA expression associated with metabolic disease and inflammation in different cell types and organisms, both in vivo and in vitro, depending on varying combinations of DFAs, doses, and the duration of treatment. However, studies are limited and heterogeneous in methodology. Additionally, recent studies demonstrated that high fat ketogenic diets, many enriched with saturated fats, do not increase serum saturated fat content in humans, and are not associated with increased inflammation. Thus, these findings shed light on the complexity of novel treatment and DFA interventions for metabolic disease and to maintain health. Further studies are needed to advance molecular therapeutic approaches, including miRNA-based strategies in human health and disease. 相似文献
7.
Cristobal Abello Constanza A Harding Alejandra P Rios Miguel Guelfand 《Journal of pediatric surgery》2021,56(5):1068-1075
Introduction: Giant omphaloceles can be a challenge for pediatric surgeons and neonatologists worldwide. It is a rare and low-frequency congenital anomaly with no standardized management schemes or treatment protocols. Over the past few decades, we have developed a simple and efficient staged management for giant omphaloceles that allows definitive closure in the neonatal period, the results of which we outline in this report.Material and methods: With IRB approval, a retrospective and multicentric cohort study was carried out between 1994 and 2019 with patients with giant omphalocele defined as an abdominal wall defect greater than 5 cm in diameter and/or that contains more than 50% of the liver within the sac. We included all patients managed with the nonsurgical silo technique. Data on demographics, gestational age, associated malformations, amnion reduction and inversion time, anatomic closure, requirement of a mesh, intra- and post-silo complications, mortality and follow-up were collected. The technique consists of the construction of a silo with an adhesive hydrocolloid dressing (Duoderm?) to achieve an omphalocele staged-reduction until complete abdominal reintegration of the liver and bowel preservation of the amnion sac. This also enables the simulation of abdominal closure before definitive surgical closure, being managed in the neonatal intensive care unit (NICU).Results: Forty patients, 21 of whom were female, were managed with this technique. The average weight was 2900 gs (890–3900), and the median gestational age was 38 weeks (28–40). In total, 37.5% of cases had an associated comorbidity. The average silo reduction time was 7.3 days (0–35), the average time of amnion inversion was 5 days (2–9), and the average time to closure was 14.6 days (6–38). Anatomical closure was achieved in 95% of cases. In 4 patients, an absorbable mesh was used to reinforce the anatomical closure, and in 2 patients (5%), a mesh (Dualmesh?) was required to achieve an abdominal closure. There was no mortality associated with this nonsurgical silo technique. The average follow-up time was 60 (6 - 288) months.Conclusion: The staged silo management of giant omphalocele in this series is safe and effective and reduces the time to closure and potential morbidity and mortality compared with traditional surgical or medical management. 相似文献
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9.
Juliana Cervantes-Theurel Alejandra Albarran-Sanchez Victor Rodriguez-Perez Etual Espinosa-Cardenas Claudia Ramirez-Renteria Aldo Ferreira-Hermosillo 《Surgery for obesity and related diseases》2021,17(2):257-262
BackgroundObstructive sleep apnea–hypopnea syndrome (OSAHS) is present in 80% of patients evaluated for bariatric surgery (BS). Extensive evaluation is not widely available, but treatment is mandatory for severe cases. The Snore, Tiredness, Observed apneas and Pressure - Body mass index, Age, Neck circumference and Gender (STOP-Bang) and Epworth questionnaires and neck-to-height ratio (NHtR) are accessible clinical tools to screen for sleep and metabolic disturbances, but their utility to detect severe OSAHS in patients with severe obesity has not been determined.ObjectivesTo evaluate the cutoff point of those clinical tools that may predict severe OSAHS, confirmed by polysomnography in patients referred for BS.SettingTertiary referral center in Mexico City.MethodsWe applied the STOP-Bang and Epworth questionnaires, evaluated anthropometric characteristics, and collected samples for arterial gasometry and metabolic parameters from 68 patients with severe obesity, who were then referred for polysomnography before their evaluation for BS.ResultsOf the 68 patients participating in the study, 67.7% were female, with a median age of 43 years (35–49 years) and a body mass index (BMI) of 45.5 kg/m2 (42.4–50.9 kg/m2; 28.3% had a BMI ≥ 50 kg/m2). A STOP-Bang cutoff >5 points had a sensitivity of 60% and specificity of 90% for detecting severe OSAHS (area under the curve [AUC] = .962); meanwhile, an NHtR >.25 had a sensitivity of 90% and specificity of 52.5% (AUC = .759). The Epworth scale score >11 points had a sensitivity of 57.1% and specificity of 83.3% (AUC = .802).ConclusionClinical data may be useful to detect severe sleep apnea in high-risk populations, allowing for rapid referral and better use of resources. 相似文献
10.
Aránzazu Caballero-Marcos Magdalena Salcedo Roberto Alonso-Fernández Manuel Rodríguez-Perálvarez María Olmedo Javier Graus Morales Valentín Cuervas-Mons Alba Cachero Carmelo Loinaz-Segurola Mercedes Iñarrairaegui Lluís Castells Sonia Pascual Carmen Vinaixa-Aunés Rocío González-Grande Alejandra Otero Santiago Tomé Javier Tejedor-Tejada José María Álamo-Martínez Luisa González-Diéguez Flor Nogueras-Lopez Gerardo Blanco-Fernández Gema Muñoz-Bartolo Francisco Javier Bustamante Emilio Fábrega Mario Romero-Cristóbal Rosa Martin-Mateos Julia Del Rio-Izquierdo Ana Arias-Milla Laura Calatayud Alberto A. Marcacuzco-Quinto Víctor Fernández-Alonso Concepción Gómez-Gavara Jordi Colmenero Patricia Muñoz José A. Pons the Spanish Society of Liver Transplantation 《American journal of transplantation》2021,21(8):2876-2884
The protective capacity and duration of humoral immunity after SARS-CoV-2 infection are not yet understood in solid organ transplant recipients. A prospective multicenter study was performed to evaluate the persistence of anti-nucleocapsid IgG antibodies in liver transplant recipients 6 months after coronavirus disease 2019 (COVID-19) resolution. A total of 71 liver transplant recipients were matched with 71 immunocompetent controls by a propensity score including variables with a well-known prognostic impact in COVID-19. Paired case–control serological data were also available in 62 liver transplant patients and 62 controls at month 3 after COVID-19. Liver transplant recipients showed a lower incidence of anti-nucleocapsid IgG antibodies at 3 months (77.4% vs. 100%, p < .001) and at 6 months (63.4% vs. 90.1%, p < .001). Lower levels of antibodies were also observed in liver transplant patients at 3 (p = .001) and 6 months (p < .001) after COVID-19. In transplant patients, female gender (OR = 13.49, 95% CI: 2.17–83.8), a longer interval since transplantation (OR = 1.19, 95% CI: 1.03–1.36), and therapy with renin–angiotensin–aldosterone system inhibitors (OR = 7.11, 95% CI: 1.47–34.50) were independently associated with persistence of antibodies beyond 6 months after COVID-19. Therefore, as compared with immunocompetent patients, liver transplant recipients show a lower prevalence of anti-SARS-CoV-2 antibodies and more pronounced antibody levels decline. 相似文献