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81.
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Lakatos PL Gyori G Halasz J Fuszek P Papp J Jaray B Lukovich P Lakatos L 《World journal of gastroenterology : WJG》2005,11(3):457-459
The authors report the case of a 60-year-old male patient. In November 2001 he developed intestinal symptoms of bloody diarrhea and abdominal pain. Colononoscopy and biopsy established the diagnosis of ulcerative colitis (proctosigmoiditis). The disease activity was moderate at the beginning. No significant laboratory alterations were found (including CEA, CA19-9), and mesalazine was started orally. He was in remission until November 2003, when he was admitted to our Outpatient Clinic for upper and right lower abdominal pain and bloody diarrhea. Colonoscopy found proctosigmoiditis with a moderate activity, gastroscopy revealed chronic gastritis, laboratory data was normal. Treatment was amended with mesalazine clysma and methylprednisolone (16 mg) orally. Symptoms ameliorated; however, right lower abdominal pain persisted. US and CT examinat'on demonstrated a pericecal cystic mass (11 cm×3.5 cm). At first pericecal abscess was suspected, as the previous US examination (6 mo earlier) had revealed normal findings. Fine needie aspiration was performed. Cytology confirmed the diagnosis of mucocele. The patientunderwent partial cecum resection and extirpation of the mucocele. He recovered well and the final histology revealed a cystadenoma of the appendix. Follow up was started. The pati雗t is now free of symptoms. Although primary adenocarcinoma of the appendix is uncommon, the authors emphasize that preoperative diagnosis of an underlying malignancy in a mucocele is important for pati雗t management; however, it is difficult on imaging studies. 相似文献
83.
Monika Dobrzyska-Mizera Monika Knitter Salvatore Mallardo Maria Cristina Del Barone Gabriella Santagata Maria Laura Di Lorenzo 《Materials》2021,14(10)
Bio-based composites made of poly(L-lactic acid) (PLLA) and β-cyclodextrin/d-limonene inclusion complex (CD-Lim) were prepared by melt extrusion. Encapsulation of volatile d-limonene molecules within β-cyclodextrin cages was proven to be a successful strategy to prevent evaporation during high-temperature processing. However, small amounts of limonene were released upon processing, resulting in the plasticization of the polymeric matrix. Morphological analysis revealed good dispersion of the filler, which acted as a nucleating agent, favoring the growth of PLLA crystals. The composites′ lowered glass transition temperature upon the addition of CD-Lim was also proved by thermomechanical analysis (DMA). Moreover, DMA revealed constant stiffness of modified materials at room temperature, which is crucial in PLLA-based formulations. 相似文献
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Raffaella Santi Alessandro Franchi Valeria Saladino Massimo Trovati Giovanna Cenacchi Massimo Squadrelli-Saraceno Gabriella Nesi 《Head and neck pathology》2015,9(2):300-304
Paragangliomas (PGs) of the head and neck region are typically benign, slow-growing neuroendocrine tumours. At times, they may exhibit unusual histological features, such as prominent stromal sclerosis (sclerosing PG), which may raise concerns of malignancy. We describe a case of sclerosing PG of the carotid body, emphasizing the value of immunohistochemical stains for differential diagnosis. A 43-year-old woman presented with a painless lump on the neck. A magnetic resonance imaging scan demonstrated a hypervascular lesion of the carotid body, which was surgically excised. Grossly, the lesion measured 1.8 cm at maximum diameter. On microscopic examination, irregular nests and tiny bundles of neoplastic cells were found between thick bands of fibrous tissue. Focal nuclear cytomegaly and marked pleomorphism were noted. Neoplastic cells proved to be immunoreactive for chromogranin, synaptophysin and neuron specific enolase, but negative for cytokeratins, smooth muscle actin and CD34. Ultrastructurally, numerous mitochondria, rough endoplasmic reticulum structures and endocrine granules were seen in the cytoplasm of the tumour cells. On consideration of the above-mentioned clinico-pathological and ultrastructural findings a diagnosis of sclerosing PG was established. Sclerosing PG is a rare entity which may mimic a malignant neoplasm. The recognition of this unusual morphological variant of PG, together with appropriate immunostains, leads to the correct diagnosis. 相似文献
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Erika Monguzzi Laura Marabini Luca Elli Valentina Vaira Stefano Ferrero Francesca Ferretti Federica Branchi Gabriella Gaudioso Alice Scricciolo Vincenza Lombardo Luisa Doneda Leda Roncoroni 《Digestive and liver disease》2019,51(1):47-54
Background
Gliadins are involved in gluten-related disorders and are responsible for the alteration of the cellular redox balance. It is not clear if the gliadin-related oxidative stress can induce DNA damage in enterocytes.Aim
To investigate any possible genotoxicity caused by gliadin and to assess its relationship with oxidative stress in vitro and ex vivo.Methods
Caco-2 cells were exposed for 6–12–24?h to increasing concentrations (250?μg/mL–1000?μg/mL) of digested gliadin. We investigated: cytotoxicity, oxidative balance (reactive oxygen species, ROS), DNA damage (comet assay and γ-H2AX detection), transglutaminase type 2 (TG2) activity and annexin V expression. H2AX and 8-OHG immunohistochemistry has been evaluated on duodenal biopsies of celiac subjects and controls.Results
Gliadin induced a significant increase (+50%) of ROS after 12?h of exposition starting with a 500?μg/mL dose of gliadin. Comet assay and γ-H2AX demonstrated DNA damage, evident at the gliadin concentration of 500?μg/mL after 24?h. TG2 activity increased in chromatin and cytoskeleton cellular compartments at different gliadin doses (250/500/1000?μg/mL). The γ-H2AX and 8-OHG immunohistochemistry was altered in the duodenal biopsies of celiac patients.Conclusions
Gliadin induces cellular oxidative stress, DNA damage and pro-apoptotic stimulation in Caco-2 cells and in the duodenal mucosa of celiac patients. 相似文献89.
90.
Perforation of the atretic pulmonary valve. Long-term follow-up 总被引:5,自引:0,他引:5
Agnoletti G Piechaud JF Bonhoeffer P Aggoun Y Abdel-Massih T Boudjemline Y Le Bihan C Bonnet D Sidi D 《Journal of the American College of Cardiology》2003,41(8):1399-1403
OBJECTIVES: We evaluated the long-term results of perforation of the pulmonary valve in patients with pulmonary atresia with an intact ventricular septum (PA-IVS). BACKGROUND: Interventional perforation of the pulmonary valve is considered the elective first stage treatment for PA-IVS, particularly in patients with a tripartite right ventricle (RV) and normal coronary circulation. However, the long-term results of this procedure are lacking. METHODS: Between January 1991 and December 2001, 39 newborns with a favorable form of PA-IVS underwent attempted perforation of the pulmonary valve. We evaluated the early and long-term outcomes. RESULTS: Median tricuspid and pulmonary z values were -1.2 and -2.4, respectively. Perforation was successful in 33 patients. Among them, 17 needed neonatal surgery, 13 did not need any surgery, and 3 had elective surgery after the first month of life. There were two procedure-related deaths, seven nonfatal procedural complications, and four postsurgical deaths. Compared with patients needing neonatal surgery, those having no or elective surgery had a higher incidence of a tripartite RV and a higher median tricuspid z value (92% vs. 53%, p = 0.04 and -1.7 vs. -0.5, p = 0.03). At a median follow-up of 5.5 years (range 0.5 to 11.5), survival was 85% and freedom from surgery was 35%. Five patients, four of whom had neonatal surgery, underwent a partial cavo-pulmonary connection. CONCLUSIONS: Our results show that this technique, although burdened by non-negligible mortality and morbidity, is effective in selected patients with a normal-sized RV. Preselection of patients allows interventional or surgical biventricular correction in the majority of cases. 相似文献