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Joseph D. Westaby Susanna T. E. Cooper Khari A. Edwards Robert H. Anderson Mary N. Sheppard 《Clinical anatomy (New York, N.Y.)》2020,33(3):394-404
Congenital heart disease is a rare but important finding in adults who experience sudden death. Examination of the congenitally malformed heart has historically been considered esoteric and best left to those with expertise. The Cardiac Risk in the Young cardiovascular pathology laboratory based at St George's University of London has now received over 6,000 cases. Of these, 21 congenitally malformed hearts were retained for research and educational purposes. Hearts were assessed using sequential segmental analysis, and causes of death were adjudicated based on thorough macroscopic examination and histology. Congenital malformations that were encountered included atrial septal defects, ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries in both its regular and congenitally corrected variants. Findings also included hearts with mirror-imaged and isomeric atrial appendages. Direct causes of death included myocardial fibrosis, pulmonary hypertension, and hemorrhage. A small but notable proportion did not reveal a substrate for arrhythmia, raising the question of whether the terminal event was due to the congenital heart disease itself, or an underlying channelopathy. Here, we demonstrate the value of simple sequential segmental analysis in describing and categorizing the cases, with the concept of the “morphological method” serving to identify the distinguishing features of the cardiac components. Clin. Anat. 33:394–404, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
3.
Vasileios Mourmouras Gabriele Cevenini Elena Cosci Maria C. Epistolato Maurizio Biagioli Letizia Barbagli Pietro Luzi Susanna Mannucci and Clelia Miracco 《Journal of cutaneous pathology》2009,36(6):637-646
Background: Nucleolin is a major nucleolar argyrophilic protein involved in carcinogenesis. There are only few studies on its tissue expression in human cancer and none in melanoma. We aimed at exploring this protein and its prognostic impact in cutaneous melanocytic lesions.
Methods: We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.
Results: Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.
Conclusion: An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma. 相似文献
Methods: We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.
Results: Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.
Conclusion: An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma. 相似文献
4.
Factors affecting aseptic loosening of 4750 total hip arthroplasties: multivariate survival analysis
Barbara Bordini Susanna Stea Manuela De Clerico Sergio Strazzari Antonio Sasdelli Aldo Toni 《BMC musculoskeletal disorders》2007,8(1):69
Background
Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure. 相似文献5.
Federico Venuta Susanna Sciomer Claudio Andreetti Marco Anile Tiziano De Giacomo Matilde Rolla Francesco Fedele Giorgio Furio Coloni 《European journal of cardio-thoracic surgery》2007,32(5):787-790
OBJECTIVE: The effects of major lung resections on cardiac function in the medium and long term have not been thoroughly evaluated. We have studied right heart function with serial Doppler echocardiography in patients undergoing lobectomy and pneumonectomy during 4 years of follow-up after surgery. METHODS: Thirty-six patients undergoing lobectomy and 15 receiving pneumonectomy were evaluated with one- and two-dimensional Doppler standard transthoracic echocardiography before surgery and 1 week, 3 months, 6 months, 1 year, and 4 years postoperatively. We have studied the right midventricular diastolic diameter (RVDD), the right ventricle free wall thickness, the tricuspid valve insufficiency (TVI) and regurgitation jet (TRJ), and the pulmonary artery systolic pressure (PASP). RESULTS: None of the patients died within the first postoperative year. After lobectomy there were no significant modifications of any variable at any time. RVDD progressively increased after pneumonectomy (26.5+/-2.2mm preoperatively vs 34.3+/-7.6 at 4 years; p<0.001). Four years after surgery all patients undergoing pneumonectomy had moderate TVI while only 55% of patients receiving lobectomy showed it (low grade in 50% and moderate in 5%). In this group of patients PASP increased from 26.1+/-2.6 mmHg preoperatively to 34.3+/-7.6 mmHg at 4 years (p<0.00001). CONCLUSIONS: Right ventricle modifications are clearly evident after pneumonectomy and even if they do not show a clear clinical impact they should not be neglected. 相似文献
6.
Abstract: Dopamine agonists and antagonists with different affinities for D1 and D2 receptors in the brain were assessed for their ability to affect clonic seizures in mice induced by chemoconvulsants. The dopamine D2 antagonists remoxipride (5-20 mg/kg) and raclopride (5-20 mg/kg), haloperidol (2.5 and 5 mg/kg) and the D1 antagonist SCH 23390 (0.3, 1.5 mg/kg) did not markedly modify seizures induced by pentylenetetrazole, picrotoxin or bicuculline. The dopamine D2 agonist quinpirole only weakly blocked the action of pentylenetetrazole while the D1 agonist SKF 38393 (1-10 mg/kg subcutaneously) caused a dose-dependent blockade of pentylenetetrazole-induced seizures. The D1/D2 agonist apomorphine given at “postsynaptic” doses (1 and 2 mg/kg) blocked pentylenetetrazole-induced seizures. The protection afforded by apomorphine against pentylenetetrazole seizures appeared to be associated with its activation of both D1 and D2 receptors since both raclopride and SCH 23390 blocked the action of apomorphine. Reserpine and the two partial dopamine autoreceptor agonists, (—)3-PPP and HW-165, at high (non-autoreceptor selective) doses induced seizures in animals treated with the subconvulsive dose of pentylenetetrazole. The overall results suggest that dopamine receptor blockade has a minor or limited effect on seizures caused by GABA inhibition. The anticonvulsant effect of dopamine agonists such as apomorphine appears to be mediated by postsynaptic dopamine D1 and D2 receptors. Stimulation of dopamine D1 receptors can reduce seizure activity caused by GABA receptor blockade possibly by facilitation of GABA transmission in the striatum and substantia nigra. 相似文献
7.
8.
J. Åberg B. Abrahamsson M. Grind G. Nyberg B. Olofsson 《European journal of clinical pharmacology》1997,52(6):471-477
Objective: The primary aim of this study was to investigate whether bioequivalence is achieved for a new fixed combination of extended-release
(ER) felodipine and controlled-release (CR/ZOK) metoprolol␣compared with the free combination of felodipine ER metoprolol
CR/ZOK. The second aim was to study whether there was an interaction in pharmacokinetics and pharmacodynamics between felodipine
and metoprolol when administered as ER formulation.
Methods: Two four-way cross-over studies were performed in 36 young subjects and 24 elderly subjects with frequent measurement of
drug plasma concentrations, blood pressures and heart rate. The pharmacokinetic analysis included enantioselective analysis
in six subjects.
Results: Bioequivalence between the fixed combination and the free combination was observed for the two drugs (mean difference 27%)
except for a minor deviation regarding Cmax of metoprolol in the elderly. No significant interaction was shown except for a small increase (6%) of metoprolol AUC in
the younger subjects. Mean plasma S-/R-enantiomer ratios were almost identical for the different treatments. Blood pressure and heart rate was significantly reduced
for the fixed combination compared with felodipine ER in the younger and the elderly subjects. No significant difference regarding
pharmacodynamics was detected between the fixed combination and the corresponding free combination.
Conclusion: The fixed combination consistently provides fairly constant and effective felodipine and metoprolol concentrations after
once-daily administration of one tablet. It is clinically interchangeable with the free combination of metoprolol CR/ZOK tablets
and felodipine ER tablets. Finally, felodipine and metoprolol do not interact on a pharmacokinetic level when administered
as the fixed combination.
Received: 29 October 1996 / Accepted in revised form: 21 March 1997 相似文献
9.
Marc Ziegler Alexandre Castro-Caldas Susanna Del Signore Olivier Rascol 《Movement disorders》2003,18(4):418-425
Piribedil is a non-ergot D2/D3 agonist with a significant antagonist action on alpha2A and alpha2C adrenergic receptor subtypes. This double-blind placebo-controlled study was undertaken to confirm the efficacy of 150 mg/day piribedil po in improving motor symptoms of idiopathic Parkinson's disease (PD) in nonfluctuating patients insufficiently controlled by a stable daily dose of levodopa (L-dopa). Efficacy was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) III score as primary criterion over 4 months. A second comparison was planned at 6 months, after possible adjustment of L-dopa. At 4 months, the rate of response, defined as a 30% decrease from baseline on UPDRS III score, was significantly greater with piribedil compared with placebo (56.4% vs. 37.7%; P = 0.040). At 6 months, the better efficacy of piribedil was maintained (61.8% of responders vs. 39.6% on placebo; P = 0.020). The difference between groups on UPDRS III change from baseline reached statistical significance only at 6 months: -10.0 points in the piribedil group vs. -6.7 points in the placebo group (P = 0.037). Secondary end-points were not significantly different. The most frequently reported adverse events were gastrointestinal symptoms (27 of 61 patients in the piribedil group vs. 13 of 54 patients in the placebo group). In conclusion, a 6-month oral administration of 150 mg/day piribedil in combination with L-dopa is well tolerated, except for minor gastrointestinal symptoms at the beginning of the treatment and significantly improves motor symptoms compared with placebo in PD nonfluctuating patients. 相似文献
10.
M.S. Ågren U. Ostenfeld M.E. Crawford K. Kiss Y. Gong C. Gluud A. FriisMøller F. Kallehave K. Raffn L.N. Jorgensen 《Wound repair and regeneration》2005,13(2):A1-A27
Extended healing time and lack of documented effective treatments of sacrococcygeal pilonidal disease create substantial problems. Locally applied zinc oxide has been reported to promote wound healing. We have compared topical zinc oxide (3%) with placebo meshes for pilonidal wounds healing by secondary intention in a randomized, double‐blind, placebo‐controlled multicenter trial. Sixty‐four consecutive patients, 53 males, aged between 18 and 60 years (median 26 years) with excised pilonidal wounds were centrally randomized to local zinc oxide (30 mg/g, n = 33) or to placebo (n = 31) mesh treatment. Patients were followed with strict recording of beneficial and harmful effects. The median healing times were 54 days (42–71 days, interquartile range, n = 33) for the zinc group and 62 days (55–82 days, n = 31) for the placebo group. This difference was not statistically different (p = 0.32). Based on Cox regression analysis initial wound volume influenced healing negatively (p = 0.016) while smoking (p = 0.011) was associated with faster wound healing. Significantly (p < 0.01) more placebo (n = 12) than zinc oxide‐treated patients (n = 3) needed antibiotics postoperatively. Although topical zinc oxide increased (p < 0.001) wound fluid zinc levels (1830 ± 405 μM, mean ± SEM) compared with placebo (3.1 ± 1.6 μM) serum‐zinc levels did not differ significantly between the zinc (13.5 ± 0.4 μM) and placebo (12.8 ± 0.4 μm) groups on postoperative day 7. No adverse events were recorded. Topical zinc oxide treatment did not accelerate time to closure of open pilonidal wounds but was associated with reduced antibiotic usage. 相似文献