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11.
John Lennon Silva Cunha Carla Isabelly Rodrigues-Fernandes Ciro Dantas Soares Celeste Snchez-Romero Pablo Agustin Vargas Cleverson Luciano Trento Bruno Augusto Benevenuto de Andrade Sílvia Ferreira de Sousa Ricardo Luiz Cavalcanti de Albuquerque-Júnior 《Head and neck pathology》2021,15(1):303
Myofibroma (MF) is a benign mesenchymal myofibroblast-derived tumor, which occurs most frequently in children, and rarely affects the maxilla. We reported a case of an aggressive intraosseous lesion found in the maxilla of a 9-year-old female child. Intraorally, the swelling extended from tooth 12 to 16, causing displacement of teeth 13, 14, and 15. Computed tomography revealed a large osteolytic lesion causing thinning and cortical erosion. Microscopically, the lesion showed a proliferation of spindle-shaped cells, with elongated nuclei and eosinophilic cytoplasm, arranged in interlaced fascicles. The immunohistochemical analysis revealed cytoplasmic positivity for α-SMA and HHF-35, and negativity for desmin, laminin, S-100, β-catenin, and CD34. Ki-67 was positive in 8% of tumor cells. The diagnosis was MF. Herein, we describe an additional case of central MF arising in the maxilla, including clinical, imaging, microscopical, and immunohistochemical features, as well as a review of the literature. 相似文献
12.
J A Ortega García D Carrizo Gallardo J Ferris i Tortajada M M P García J O Grimalt 《Archives of disease in childhood》2006,91(8):642-646
BACKGROUND: Exposure to organochlorine compounds (OCs) has been a subject of interest in recent years, given their potential neurotoxicity. Meconium is easily available and accumulates neurotoxicants and/or metabolites from the 12th week of gestation. AIMS: To determine whether neurotoxicants, specifically OCs, could be detected in serially collected meconium, and to compare the results with those obtained in cord blood samples. METHODS: A sample of cord blood and three serial stool samples were analysed in 10 newborns. Pentachlorobenzene (PeCB), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane (p,p'-DDT) and its metabolite dichlorodiphenyl dichloroethylene (p,p'-DDE), and hexachlorocyclohexane isomers (alpha-, beta-, gamma-, and delta-HCH) were analysed by gas chromatography. RESULTS: From serial stool collection and analysis in newborns, there was an increase in the concentrations of HCB, p,p'-DDE, PCBs, and beta-HCH between the first and last stools of the newborn. Levels of DDT diminished as pregnancy progressed. Concentrations in cord blood were positively associated with concentrations in meconium for p,p'-DDE and beta-HCH. CONCLUSIONS: Meconium is a very useful instrument for the investigation of fetal exposure to neurotoxicants; serial collection and analysis of meconium should estimate the timing and degree of in utero exposure of the fetus to neurotoxicants. Analysis and interpretation of neurotoxicants in meconium results is a complex process. Measurement in meconium of a wide range of neurotoxic substances should facilitate early identification of harmful exposures, and enable rehabilitation and instigation of preventive measures. 相似文献
13.
Agustin Dietrich Matias Nicolas Jose Iniesta David Eduardo Smith 《International journal of surgery case reports》2012,3(12):622-624
INTRODUCTIONThe development of empyema as a result of an intra-abdominal pathology is a rare condition.PRESENTATION OF CASEWe present a 31-year-old woman at 28 weeks’ gestation who was referred to our hospital with diagnosis of pneumonia with pleural effusion. She presented with signs of septicemia and fetal distress. A thoracic-abdominal-pelvic CT-scan showed a right pleural effusion with a retroperitoneal collection in contact with the pleural space. Due to her critical condition, immediate surgical exploration and pregnancy interruption was decided. The fetus was delivered by cesarean with satisfactory vitality. After abdominal exploration, a retrocecal appendicular abscess was evidenced and appendectomy was performed. Subsequently, the right chest was accessed through a posterolateral thoracotomy. An empyema with lung abscess and purulent fluid accessing from the retroperitoneum at the posterior pleural space was found. Due to parenchymal compromise, a right inferior lobectomy was performed. The patient had an uneventful recovery and was discharged at postoperative day 10.DISCUSSIONA septic condition in a pregnant patient with significant thoraco-abdominal infection requires an aggressive approach, with interruption of pregnancy and urgent exploration of the chest and abdomen.CONCLUSIONWhen an empyema is developed in absence of lung disease or other intrathoracic cause, intra-abdominal origin should be considered. 相似文献
14.
Laura Pérez-Egido María Antonia García-Casillas Isabel Simal María Fanjul Agustin Cañizo Julio A. Cerdá Beatriz Fernandez Manuel de la Torre Javier Ordoñez Juan Carlos de Agustin 《Journal of pediatric surgery》2019,54(4):693-695
Introduction
New digital thoracic drainage systems allow an objective measurement of air leakage. They have proven their usefulness in the postoperative thoracic surgery in adults, but there is little experience with its use in the pediatric population. The objective of our study is to analyze their safety and effectiveness in the postoperative period of the pediatric patients.Method
A prospective consecutive observational study was done. All patients submitted to pulmonary resection between 2011 and 2017 and in whom digital thoracic drainage system was used (Thopaz Chest Drain System, Medela, Switzerland) were prospectively enrolled in this study. We analyzed variables: duration of chest tube (CT), days of hospitalization and radiographs in the immediate postoperative period related to the presence of CT. This group was compared with a historical cohort of patients (from 2011 to 2015) with a pulmonary resection in whom the traditional thoracic drainage was used. For the statistical analysis, the Mann–Whitney U-Test was used for independent samples.Result
Twenty-six patients were included, Digital drainage system was used in13 patients and traditional drainage was used in 13 patients. The median age was 18?months (12?days-14?years). The mean number of days with the chest tube was 1.69?±?0.6 in digital drainage group versus 5.38?±?4?days in traditional drainage group (p?<?0.05) The mean number of postoperative radiographs was 2.8?±?1.1 in digital drainage group versus 6.23?±?5.2 radiographs in traditional drainage group (p?<?0.05). The average hospital stay in digital drainage group was 5.69?±?2.7?days versus 7?±?4.7?days in the traditional drainage group (p?>?0.05). No complications related to the use of digital drainage group were registered.Conclusion
The digital thoracic drainage systems provide an objective measurement of air leakage, allowing early chest tube removal and decreasing the number of radiographs performed postoperatively. Its use in the pediatric population appears to be safe and potentially beneficial.Level of evidence
II. 相似文献15.
Julia C Bartsch Pawel Fidzinski Jojanneke HJ Huck Heide H?rtnagl Richard Kovács Agustin Liotta Josef Priller Christian Wozny Joachim Behr 《Neuropsychopharmacology》2015,40(4):987-995
Dopaminergic hyperfunction and N-methyl-D-aspartate receptor (NMDAR) hypofunction have both been implicated in psychosis. Dopamine-releasing drugs and NMDAR antagonists replicate symptoms associated with psychosis in healthy humans and exacerbate symptoms in patients with schizophrenia. Though hippocampal dysfunction contributes to psychosis, the impact of NMDAR hypofunction on hippocampal plasticity remains poorly understood. Here, we used an NMDAR antagonist rodent model of psychosis to investigate hippocampal long-term potentiation (LTP). We found that single systemic NMDAR antagonism results in a region-specific, presynaptic LTP at hippocampal CA1-subiculum synapses that is induced by activation of D1/D5 dopamine receptors and modulated by L-type voltage-gated Ca2+ channels. Thereby, our findings may provide a cellular mechanism how NMDAR antagonism can lead to an enhanced hippocampal output causing activation of the hippocampus-ventral tegmental area-loop and overdrive of the dopamine system. 相似文献
16.
J F Noguera Aguilar I Amengual Antich A Plaza Martínez C Tortajada Collado J M Morón Canis J J Pujol Tugores 《Revista española de enfermedades digestivas》2004,96(5):322-330
AIM: to investigate the influence of different experimental manipulations in a model of colonic experimental carcinogenesis with pharmacological induction in the rat. EXPERIMENTAL DESIGN: a total of 90 Sprague-Dawley male rats, divided into three groups, were used: non-surgical (n = 30); surgical with colonic trauma (n = 20), and surgical with colo-colonic anastomosis (n = 40). Carcinogenic induction was carried out with 1-2 dimethylhydrazine dihydrochloride. Colonic adenocarcinomas were identified and the number of tumors, as well as tumoral surface and percentage of tumoral surface was established. One-way ANOVA and Chi-square were employed for the statistical analysis. RESULTS: the number of tumors was greater in the surgical group than in the control group, and tumors preferentially developed around the manipulated colon. Surface and tumoral percentage were greater in the surgical group than in the control group, being also greater in the anastomosis group than in the group with colonic trauma. Within anastomosis groups, a greater tumor surface and percentage was found in the group with titanium than in the group with reabsorbable material. CONCLUSIONS: the experimental manipulation of the colon in rats enhances drug-induced colon carcingenesis. The creation of an anastomosis further increases the carcinogenic process compared with simulated anastomosis. This process is also enhanced by the quantity of suture material included in the anastomosis, and by the non-reabsorbable nature of the materials used in the anastomotic line. 相似文献
17.
J F Noguera Aguilar I Amengual Antich A Plaza Martínez J Ibarra de la Rosa C Tortajada Collado A Gamundí Gamundí J J Pujol Tugores 《Revista española de enfermedades digestivas》2005,97(9):637-647
BACKGROUND: An overexpression of cyclooxygenase-2 (COX-2) has been seen in colon tumors; therefore, COX-2 specific inhibitors may be used as preventive agents. The aim of this study was to investigate the effect of both selective and non-selective COX-2 inhibitors on the incidence of colonic tumors in a model of chemical carcinogenesis in the rat. DESIGN: Experimental study with 65 male Sprague-Dawley rats randomly assigned to one of four groups: (a) control (n = 20), with chemical carcinogenesis using 1-2 dimethylhydrazine (1-2 DMH); (b) acetylsalicylic acid (ASA) (n = 15), with chemical carcinogenesis and the addition of ASA at 30 mg/kg; (c) low-dose rofecoxib (n = 15), with chemical carcinogenesis and the addition of rofecoxib at a dose of 1.2 mg/kg; (d) high-dose rofecoxib (n = 15), with carcinogenesis and the addition of rofecoxib at 3 mg/kg. Carcinogenic induction was performed with 1-2 DMH at a weekly dose of 25 mg/kg for 18 weeks. The main parameter evaluated was percentage of neoplastic colonic tissue, which relates tumor surface area to colon surface area. RESULTS: Rofecoxib at a dose of 3 mg/kg significantly reduced chemical colon carcinogenesis in rats (p < 0.01). Rofecoxib in lower doses had the same effect on adenomas (p < 0.05) with no effect on adenocarcinomas. Rofecoxib reduced COX-2 expression in tumoral tissue from adenomas and adenocarcinomas (p < 0.01). CONCLUSIONS: Rofecoxib prevents chemical colon carcinogenesis in the rat, with a reduction of tumoral colonic percentage in adenocarcinomas and tumoral COX-2 expression. 相似文献
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20.
Juan M. Aranda M.D. Benjamin Befeler M.D. Nabil El-Sherif M.D. Agustin Castellanos M.D. Ralph Lazzara M.D. 《The American journal of medicine》1976,60(7):997-1004
The conditions associated with prolapse of the posterior leaflet of the mitral valve are multiple. The mechanisms of mitral valve prolapse as well as the pathogenesis of pain and ectopic impulse formation are reviewed. Propranolol appears to be the drug of choice for the symptomatic treatment of patients with this syndrome since it decreases myocardial oxygen demand and wall tension thus reducing or abolishing the discrepancy between myocardial oxygen demand and supply within the mitral apparatus. It has also been reported to modify the auscultatory findings associated with this condition.
The frequency of this mitral valve abnormality in patients with obstructive coronary artery disease is reviewed. It appears that prolapse of the posterior leaflet scallops in patients with significant obstructive coronary artery disease represents an intermediate stage before mitral insufficiency occurs. This group of patients with papillary muscle dysfunction includes those with prolapsed leaflets without mitral insufficiency, those with systolic murmurs and compensated heart failure and others with progressive cardiac decompensation and severe mitral regurgitation. 相似文献