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61.
62.
Granulocyte-macrophage colony-stimulating factor mRNA stabilization enhances transgenic expression in normal cells and tissues 总被引:2,自引:1,他引:2
To increase transgenic production of granulocyte-macrophage colony- stimulating factor (GM-CSF), we mutated the mRNA's 3'-untranslated region, AUUUA instability elements. Expression vectors containing human or murine GM-CSF cDNAs coding for wild-type (GM-AUUUA) or mutant versions with reiterated AUGUA repeats (GM-AUGUA) were transfected into cells in culture or animals using particle-mediated gene-transfer technology. Normal peripheral blood mononuclear cells accumulated 20- fold greater levels of GM-CSF mRNA and secreted comparably greater amounts of cytokine after transfection with hGM-AUGUA expression vectors versus hGM-AUUUA. hGM-AUGUA mRNA was fivefold more stable (t 1/2 = 95 minutes) than hGM-AUUUA mRNA (t 1/2 = 20 minutes), accounting for elevated steady-state levels. Transfection site extracts and serum samples obtained 24 hours after gene transfer of hGM-AUGUA cDNA into mouse skin contained greater than 32 ng/mL and 650 pg/mL of GM-CSF protein, respectively, compared with 0.33 ng/mL and less than 8 pg/mL for hGM-AUUUA cDNA. GM-CSF produced from mGM-AUGUA cDNA transfected into rat abdominal epidermis induced a profound neutrophil infiltrate. These data suggest a novel strategy for enhanced production of biologically active cytokines by normal cells after in vivo gene transfer. 相似文献
63.
Sergio Leonardi Felice Gragnano Greta Carrara Giuseppe Gargiulo Enrico Frigoli Pascal Vranckx Dario Di Maio Vanessa Spedicato Emanuele Monda Luigi Fimiani Vincenzo Fioretti Fabrizio Esposito Marisa Avvedimento Fabio Magliulo Attilio Leone Salvatore Chianese Michele Franzese Martina Scalise Marco Valgimigli 《Journal of the American College of Cardiology》2021,77(4):375-388
BackgroundContemporary definitions of bleeding endpoints are restricted mostly to clinically overt events. Whether hemoglobin drop per se, with or without overt bleeding, adversely affects the prognosis of patients with acute coronary syndrome (ACS) remains unclear.ObjectivesThe aim of this study was to examine in the MATRIX (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of Angiox) trial the incidence, predictors, and prognostic implications of in-hospital hemoglobin drop in patients with ACS managed invasively stratified by the presence of in-hospital bleeding.MethodsPatients were categorized by the presence and amount of in-hospital hemoglobin drop on the basis of baseline and nadir hemoglobin values and further stratified by the occurrence of adjudicated in-hospital bleeding. Hemoglobin drop was defined as minimal (<3 g/dl), minor (≥3 and <5 g/dl), or major (≥5 g/dl). Using multivariate Cox regression, we modeled the association between hemoglobin drop and mortality in patients with and without overt bleeding.ResultsAmong 7,781 patients alive 24 h after randomization with available hemoglobin data, 6,504 patients (83.6%) had hemoglobin drop, of whom 5,756 (88.5%) did not have overt bleeding and 748 (11.5%) had overt bleeding. Among patients without overt bleeding, minor (hazard ratio [HR]: 2.37; 95% confidence interval [CI]: 1.32 to 4.24; p = 0.004) and major (HR: 2.58; 95% CI: 0.98 to 6.78; p = 0.054) hemoglobin drop were independently associated with higher 1-year mortality. Among patients with overt bleeding, the association of minor and major hemoglobin drop with 1-year mortality was directionally similar but had wider CIs (minor: HR: 3.53 [95% CI: 1.06 to 11.79]; major: HR: 13.32 [95% CI: 3.01 to 58.98]).ConclusionsAmong patients with ACS managed invasively, in-hospital hemoglobin drop ≥3 g/dl, even in the absence of overt bleeding, is common and is independently associated with increased risk for 1-year mortality. (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of Angiox; NCT01433627) 相似文献
64.
Avinainder Singh Ankur Gupta Bradley L. Collins Arman Qamar Keri L. Monda David Biery J. Antonio G. Lopez Sarah D. de Ferranti Jorge Plutzky Christopher P. Cannon James L. Januzzi Marcelo F. Di Carli Khurram Nasir Deepak L. Bhatt Ron Blankstein 《Journal of the American College of Cardiology》2019,73(19):2439-2450
BackgroundThere are limited data on the prevalence and treatment of familial hypercholesterolemia (FH) among U.S. adults who experience a myocardial infarction (MI) at a young age.ObjectivesThis study aimed to evaluate the prevalence of clinically defined FH and examine the rates of statin utilization and low-density lipoprotein cholesterol (LDL-C) achieved 1-year post MI.MethodsThe YOUNG-MI registry is a retrospective cohort study that includes patients who experience an MI at or below age 50 years between 2000 and 2016 at 2 academic centers. Probable or definite FH was defined by the Dutch Lipid Clinic criteria. Outcomes included the proportion of patients classified as probable or definite FH, use of lipid-lowering therapy, and LDL-C achieved 1-year post MI.ResultsThe cohort consisted of 1,996 adults with a median age of 45 years; 19% were women, and 54% had ST-segment elevation MI. Probable/definite FH was present in 180 (9%) of whom 42.8% were not on statins prior to their MI. Of the 1,966 patients surviving until hospital discharge, 89.4% of FH patients and 89.9% of non-FH patients were discharged on statin therapy (p = 0.82). Among FH patients, 63.3% were discharged on high-intensity statin compared with 48.4% for non-FH patients (p < 0.001). At 1-year follow-up, the percent reduction in LDL-C among FH patients was ?44.4% compared with ?34.5% (p = 0.006) in non-FH patients. The proportion of patients with LDL-C ≥70 mg/dl was higher among FH patients (82.2%) compared with non-FH patients (64.5%; p < 0.001).ConclusionsClinically defined FH was present in nearly 1 of 10 patients with MI at a young age. Only two-thirds of FH patients were discharged on high-intensity statin therapy, and the vast majority had elevated LDL-C at 1 year. These findings reinforce the need for more aggressive lipid-lowering therapy in young FH and non-FH patients post-MI. 相似文献
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67.
Anita N. Vasavada Ellis Hughes Derek D. Nevins Steven M. Monda David C. Lin 《Annals of biomedical engineering》2018,46(11):1844-1856
Spine musculoskeletal models used to estimate loads and displacements require many simplifying assumptions. We examined how assumptions about subject size and vertebral positions can affect the model outcomes. Head and neck models were developed to represent 30 subjects (15 males and 15 females) in neutral posture and in forward head postures adopted while using tablet computers. We examined the effects of (1) subject size-specific parameters for head mass and muscle strength; and (2) vertebral positions obtained either directly from X-ray or estimated from photographs. The outcome metrics were maximum neck extensor muscle moment, gravitational moment of the head, and gravitational demand, the ratio between gravitational moment and maximum muscle moment. The estimates of maximum muscle moment, gravitational moment and gravitational demand were significantly different when models included subject-specific vertebral positions. Outcome metrics of models that included subject-specific head and neck size were not significantly different from generic models on average, but they had significant sex differences. This work suggests that developing models from X-rays rather than photographs has a large effect on model predictions. Moreover, size-specific model parameters may be important to evaluate sex differences in neck musculoskeletal disorders. 相似文献
68.
Luo DZ Vermijlen D Ahishali B Triantis V Vanderkerken K Kuppen PJ Wisse E 《World journal of gastroenterology : WJG》2000,6(4):546-552
AIM Several triggering receptors have been described to be involved in natural killer (NK) cellmediated target cytotoxicity. In these studies, NK cells derived from blood or spleen were used. Pit cells are liver-specific NK cells that possess a higher level of natural cytotoxicity and a different morphology when compared to blood NK cells. The aim of this study was to characterize the role of the NK-triggering molecules NKR-P1A, ANK61 antigen, and CD45 in pit cell-mediated killing of target cells. METHODS 51 Cr-release and DNA fragmentation were used to quantify target cell lysis and apoptosis, respectively. RESULTS Flow cytometric analysis showed that pit cells expressed CD45, NKR-P1A, and ANK61 antigen. Treatment of pit cells with monoclonal antibody ( mAb ) to CD45 ( ANK74 ) not only inhibited CC531s or YAC-1 target lysis but also apoptosis induced by pit cells. The mAbs to NKRP1A (3.2.3) and ANK61 antigen (ANK61) had no effect on pit cell-mediated CC531s or YAC-1 target cytolysis or apoptosis, while they did increase the Fcγ receptor positive (FcγR+) P815 cytolysis and apoptosis. This enhanced cytotoxicity could he inhibited by 3,4-dichloroisocoumarin, an inhibitor of granzymes. CONCLUSION These results indicate that CD45 participates in pit cell-mediated CC531s and YAC-1 target cytolysis and apoptosis. NKR-P1A and ANK61 antigen on pit cells function as activation structures against FcγR+ P815 cells, which was mediated by the perforin/granzyme pathway. 相似文献
69.
Anatomic and electrophysiologic substrate of the permanent form of junctional reciprocating tachycardia 总被引:1,自引:0,他引:1
G Critelli J J Gallagher V Monda F Coltorti M Scherillo L Rossi 《Journal of the American College of Cardiology》1984,4(3):601-610
Data are reported on three patients with the permanent form of junctional reciprocating tachycardia, in whom conduction over a slow accessory pathway was observed after His bundle ablation. Tachycardia was almost incessant and showed a retrograde P wave (P') and RP' interval longer than P'R interval in all patients; during sinus rhythm, the PR interval was normal and there was no evidence of a delta wave. An accessory pathway with a long conduction time located in the posterior pyramidal space provided the retrograde limb of the reentry circuit. After His bundle ablation, the accessory pathway was capable of conducting in both anterograde and retrograde directions with decremental properties in all patients. Postmortem documentation of the accessory pathway was achieved in one patient. Serial sections revealed an accessory atrioventricular connection composed of ordinary myocardium joining the lower rim of the coronary sinus outlet to the uppermost ventricular muscle. This anomalous atrioventricular connection pursued a sinuous, tortuous path. As a result of changing cross-sectional area, such an accessory pathway might exhibit slow conduction, thus explaining its decremental characteristics. 相似文献
70.