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91.
BACKGROUND: We evaluated the in-hospital and long-term effects of surgical grafting of a dominant graftable right coronary artery tributary of an infarcted nonischemic territory in patients with triple-vessel disease who were undergoing coronary artery bypass grafting. METHODS: Of 303 consecutive patients undergoing coronary artery bypass grafting with 3-vessel coronary disease and a dominant right coronary artery tributary of an infarcted nonischemic territory, 154 were randomized to right coronary artery revascularization and 149 to no right coronary artery grafting. In all cases, standard on-pump surgical myocardial revascularization was performed. RESULTS: Overall hospital mortality was 2 of 154 versus 1 of 149 (P =.97); no difference in in-hospital outcome was observed between the 2 groups. At follow-up, cardiac event-free survival was 84 of 152 in the right coronary artery grafting series and 62 of 148 in the non-right coronary artery grafting group (P =.20). However, when the analysis was limited to surviving patients without new scintigraphic evidence of ischemia (to avoid confounding factors derived from ischemia in the left coronary system or right coronary artery graft malfunction), we found that patients who received a right coronary artery graft had fewer cardiac events, a lower incidence of arrhythmia, and less left ventricular dilatation than did the non-right coronary artery revascularized series. CONCLUSIONS: Surgical grafting of a right coronary artery tributary of an infarcted nonischemic territory in patients with 3-vessel coronary artery disease submitted to coronary artery bypass grafting improved late electric stability, ventricular geometry, and event-free survival but did not affect in-hospital or 10-year survival.  相似文献   
92.
BACKGROUND: The angiographic patency of composite Y internal thoracic artery-saphenous vein grafts has not been investigated in detail. METHODS: Twenty-five patients who received composite Y internal thoracic artery-saphenous vein grafts had control angiography and vasoactive challenges with serotonin, acetylcholine, and isosorbide dinitrate at a mean of 2.5 +/- 1.2 years after surgery. RESULTS: The perfect patency rate of composite Y internal thoracic artery-saphenous vein grafts was 72% (18/25). The distal portion of the internal thoracic artery was stringed in 4 patients and occluded in 2. The saphenous branch of the composite Y internal thoracic artery-saphenous vein grafts was found patent in all patients except 1. No failures were reported in the proximal tract of the internal thoracic artery. The distal tract of the internal thoracic artery showed reduced capacity of endothelium-mediated relaxation. CONCLUSION: The short-term patency of composite Y internal thoracic artery-saphenous vein grafts is suboptimal and markedly influenced by distal runoff and native flow competition.  相似文献   
93.
BACKGROUND: The radial artery has recently been proposed as an alternative arterial conduit for surgical myocardial revascularization. This study was conceived to evaluate the degree of atherosclerotic involvement of the radial artery in patients with coronary artery disease and the eventual influence of a subtle degree of preoperative atherosclerosis on the midterm results of radial artery grafts. METHODS AND RESULTS: The intima-media thickness of the radial artery, common carotid artery, and internal thoracic artery was evaluated in 42 coronary artery disease patients and in 26 control patients. All radial arteries were then used for myocardial revascularization; 30 patients submitted to control angiography after 5 years. The mean intima-media thickness was 0.92 +/- 0.22 mm for the common carotid artery, 0.54 +/- 0.16 mm for the internal thoracic artery, 0.55 +/- 0.11 mm for the radial artery in coronary artery disease patients versus 0.79 +/- 0.14 mm, 0.52 +/- 0.11 mm, and 0.56 +/- 0.09 mm, respectively, in control patients (P =.001 only for the common carotid artery). No correlation was found between the intima-media thickness of the carotid, internal thoracic, and radial artery. No correlation was found between the preoperative intima-media thickness of the radial artery and the midterm patency and endothelial-mediated vasodilating capacity of radial artery grafts. CONCLUSION: In coronary artery disease patients, radial artery atherosclerotic involvement is more frequent than that of the gold standard internal thoracic artery but still by far less severe than that of the common carotid artery. The early atherosclerotic signs often observed in the radial artery do not seem to have the potential to influence radial artery graft patency and endothelial function.  相似文献   
94.
Motor phenotypes of Parkinson's disease (PD) are recognized to have different prognosis and therapeutic response, but the neural basis for this clinical heterogeneity remains largely unknown. The main aim of this study was to compare differences in structural connectivity metrics of the main motor network between tremor‐dominant and nontremor PD phenotypes (TD‐PD and NT‐PD, respectively) using probabilistic tractography‐based network analysis. A total of 63 PD patients (35 TD‐PD patients and 28 NT‐PD patients) and 30 healthy controls underwent a 3 T MRI. Next, probabilistic tractography‐based network analysis was performed to assess structural connectivity in cerebello‐thalamo‐basal ganglia‐cortical circuits, by measuring the connectivity indices of each tract and the efficiency of each node. Furthermore, dopamine transporter single‐photon emission computed tomography (DAT‐SPECT) with 123I‐ioflupane was used to assess dopaminergic striatal depletion in all PD patients. Both PD phenotypes showed nodal abnormalities in the substantia nigra, in agreement with DAT‐SPECT evaluation. In addition, NT‐PD patients displayed connectivity alterations in nigro‐pallidal and fronto‐striatal pathways, compared with both controls and TD‐PD patients, in which the same motor connections seemed to be relatively spared. Of note, in NT‐PD group, rigidity‐bradykinesia score correlated with fronto‐striatal connectivity abnormalities. These findings demonstrate that structural connectivity alterations occur in the cortico‐basal ganglia circuit of NT‐PD patients, but not in TD‐PD patients, suggesting that these anatomical differences may underlie different motor phenotypes of PD. Hum Brain Mapp 38:4716–4729, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
95.
Dental roots that have been exposed to the oral cavity and periodontal pocket environment present superficial changes, which can prevent connective tissue reattachment. Demineralizing agents have been used as an adjunct to the periodontal treatment aiming at restoring the biocompatibility of roots.

Objective

This study compared four commonly used demineralizing agents for their capacity of removing smear layer and opening dentin tubules.

Methods

Fifty fragments of human dental roots previously exposed to periodontal disease were scaled and randomly divided into the following groups of treatment: 1) CA: demineralization with citric acid for 3 min; 2) TC-HCl: demineralization with tetracycline-HCl for 3 min; 3) EDTA: demineralization with EDTA for 3 min; 4) PA: demineralization with 37% phosphoric acid for 3 min; 5)Control: rubbing of saline solution for 3 min. Scanning electron microscopy was used to check for the presence of residual smear layer and for measuring the number and area of exposed dentin tubules.

Results

Smear layer was present in 100% of the specimens from the groups PA and control; in 80% from EDTA group; in 33.3% from TC-HCl group and 0% from CA group. The mean numbers of exposed dentin tubules in a standardized area were: TC-HCl=43.8±25.2; CA=39.3±37; PA=12.1±16.3; EDTA=4.4±7.5 and Control=2.3±5.7. The comparison showed significant differences between the following pairs of groups: TC-HCl and Control; TC-HCl and EDTA; CA and Control; and CA and EDTA. The mean percentages of area occupied by exposed dentin tubules were: CA=0.12±0.17%; TC-HCl=0.08±0.06%; PA=0.03±0.05%; EDTA=0.01±0.01% and Control=0±0%. The CA group differed significantly from the others except for the TC-HCl group.

Conclusion

There was a decreasing ability for smear layer removal and dentin tubule widening as follows: AC>TC-HCl>PA>EDTA. This information can be of value as an extra parameter for choosing one of them for root conditioning.  相似文献   
96.
A 78-year-old with healed septal necrosis suffered a recurrent myocardial infarction of the anterior wall following the administration of isosorbide dinitrate 5 mg sublingually. After detailing the course of events, we discuss the role of paradoxical coronary spasm and hypotension-mediated myocardial ischemia occurring downstream to significant coronary arterial stenosis in the pathophysiology of acute coronary insufficiency.  相似文献   
97.
We determined peripheral blood (PB) and biopsy (Bx) RNA expression signatures in a Brazilian and US cohort of kidney transplant patients. Phenotypes assigned by precise histology were: acute rejection (AR), interstitial fibrosis/tubular atrophy/chronic rejection (CR), excellent functioning transplants (TX), and glomerulonephritis recurrence (GN). Samples were analyzed on microarrays and profiles from each cohort were cross‐validated on the other cohort with similar phenotypes. We discovered signatures for each tissue: (1) AR vs TX, (2) CR vs TX, and (3) GN vs TX using the Random Forests algorithm. We validated biopsies signatures of AR vs TX (area under the curve [AUC] 0.97) and CR vs TX (AUC 0.87). We also validated both PB and Bx signatures of AR vs TX and CR vs TX with varying degrees of accuracy. Several biological pathways were shared between AR and CR, suggesting similar rejection mechanisms in these 2 clinical phenotypes. Thus, we identified gene expression signatures for AR and CR in transplant patients and validated them in independent cohorts of significantly different racial/ethnic backgrounds. These results reveal that there are strong unifying immune mechanisms driving transplant diseases and identified in the signatures discovered in each cohort, suggesting that molecular diagnostics across populations are feasible despite ethnic and environmental differences.  相似文献   
98.

Aims

To assess the effects of a Pilates exercise program compared to conventional pelvic floor muscle training (PFMT) protocol on pelvic floor muscle strength (PFMS) in patients with post‐prostatectomy urinary incontinence.

Methods

Patients were randomized into three treatment groups (G1: Pilates, G2: electrical stimulation combined with PFMT, and G3: control group). Duration of therapy was 10 weeks. Baseline assessment included the 24 h pad‐test and the ICI‐Q questionnaire. PFMS was measured using a manometric perineometry device at baseline and 4 months after radical prostatectomy (RP). The level of significance was P < 0.05.

Results

One hundred twenty three patients were randomized and 104 patients completed the study protocol (G1: n = 34; G2: n = 35; G3: n = 35). Post‐treatment assessment showed statistically significant improvements in maximum strength in G2, increased endurance in G1 and G2, and increment of muscle power in all three groups (P < 0.05). However, there were no significant differences in the mean changes of maximum strength, endurance, and muscle power between groups after treatment (P > 0.05). G1 and G2 achieved a higher number of fully continent patients than G3 (P < 0.05). At the end of treatment, 59% of patients in G1, 54% in G2, and 26% in G3 were continent (no pads/day).

Conclusions

Improvements in PFMS parameters were distinct among active treatment groups versus controls, but did not predict recovery of urinary continence at final assessment. The Pilates method promoted similar outcomes in the proportion of fully continent patients when compared to conventional PFMT 4 months after RP.  相似文献   
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