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531.
Celsior is a new extracellular-type cardiac preservation solution. We recently developed an apparatus for preservation using low-pressure continuous coronary perfusion. The purpose of this study was to investigate the efficacy of coronary perfusion with an oxygenated Celsior solution using the new apparatus for prolonged cardiac preservation. Adult mongrel dogs weighing 9–13 kg were divided into two groups: the coronary perfusion group (CP; n=5) and the simple immersion group (SI; n=7). The coronary vascular beds were washed out with a 4°C Celsior solution following cardiac arrest using the same solution, and their hearts were excised. In the CP group, the graft was immersed in a 4°C Celsior solution and perfused with the same oxygenated solution. In the SI group, the graft was simply immersed in a 4°C Celsior solution. -adenosine triphosphate (-ATP), phosphocreatine (Pcr), inorganic phosphate (Pi) levels and myocardial pH (pHi) were measured immediately after excising the heart, and at 3, 6, and 12 hours after preservation. -ATP, Pcr, and Pi values were expressed as a percentage of control values, which were measured immediately after excising the heart. -ATP/Pi and Pcr/Pi levels were significantly higher in the CP group than in the SI group at 6 and at 12 hours after preservation. The pHi levels during preservation were significantly higher in the CP group than in the SI group. Low-pressure hypothermic coronary perfusion with an oxygenated Celsior solution is effective for long-term heart preservation.This paper was presented in part at the 41st Annual World Congress of the International College of Angiology, Sapporo Japan, July 1999.  相似文献   
532.
OBJECTIVE: The advancement of hematopoietic stem cell transplantation techniques and the increase in frequency of hematological malignancy in older patients are expected to expand the indications to include more elderly patients. We investigated the problem of allogeneic bone marrow transplantation (allo-BMT) in patients over 40 years old. PATIENTS AND METHODS: We retrospectively analyzed 21 consecutive patients (13 males and 8 females) over 40 years old who underwent allo-BMT at our center during the past 12 years. RESULTS: The patients had a median age of 46 years, and 5 patients were over 50 years old. There were 8 cases of acute myelogenous leukemia (AML), 5 cases of acute lymphocytic leukemia (ALL), 6 cases of chronic myelogenous leukemia (CML) and 2 cases of myelodysplastic syndrome (MDS). The 3-year overall survival rate was 43.0%. Overall survival was associated with recovery of platelets in less than 30 days and recovery of neutrophil counts in less than 15 days. We did not observe any severe graft-versus-host disease (GVHD) or regimen-related toxicities. Twelve patients died of transplantation-related diseases. CONCLUSION: A faster recovery of the neutrophil and platelet counts was significantly associated with overall survival. Decreasing transplantation-related death, particularly by infection control, in allo-BMT in patients over age 40 is an important problem.  相似文献   
533.
Fibroblast growth factor (FGF) 23 shares a fundamentally common structure with the members of the FGF family and has a unique sequence extension at the C-terminus. The molecular behavior of FGF23 as a systemic factor can be justified by the altered conformation of the beta-trefoil structure similar to that suspected in FGF19. On the other hand, the biological activity of FGF23 is quite distinct from those of other FGFs and requires the C-terminal unique extended structure. Two types of enzyme-linked immunosorbent assays (ELISA) have been developed to detect the intact mature form of FGF23 and its C-terminal portion. The former ELISA method enables the detection of rodent FGF23 and human FGF23. Studies on experimental animal models and laboratory examinations of physiologic and disordered conditions using these assays are contributing toward elucidating the physiology and pathophysiology of FGF23.  相似文献   
534.
It is known that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) enhance the expression- of the low-density lipoprotein (LDL) receptor and lower the level of LDL cholesterol in the blood. But, a triglyceride (TG)-lowering effect is also observed during their administration. To clarify the possibility that statins enhance LPL activity and its mechanism, the effects of statins on the expression of LPL in adipocytes were studied. When statins (pravastatin, simvastatin, atorvastatin and pitavastatin) were added to the culture medium of mouse 3T3-L1 preadipocytes at final concentrations of 1 microM for 3 days, LPL activity increased. Pitavastatin increased the activity the most. Western and Northern blotting showed that LPL protein and m-RNA were strongly expressed on the addition of pitavastatin. With the addition of mevalonate (10 microM, 3 days), LPL activity weakened significantly. Statins, especially pitavastatin, increased the expression of LPL in 3T3-L1 preadipocytes. The TG-lowering effect of pitavastatin might be mediated by enhancement of LPL production in adipocytes.  相似文献   
535.
BACKGROUND: There are few reports that examine the current imaging and management techniques according to the severity of acute pulmonary embolism (APE) or that clarify whether the management strategy ameliorated the mortality from APE. METHODS AND RESULTS: The study group were 456 patients with APE who were clinically diagnosed before their death. The severity at diagnosis, and the imaging and management techniques were analyzed. Mortality from APE was 0.8% in patients without shock nor right ventricular overload, 2.7% in patients with right ventricular overload without shock, 15.6% in patients with shock, and 52.4% in patients with cardiopulmonary arrest (p<0.0001). In the more severe cases, pulmonary angiography and trans-thoracic echocardiography were used more frequently, whereas both ventilation and perfusion lung scans were used less frequently. Computed tomography was used widely, regardless of the severity. Thrombolytic therapy and catheter therapy were used more frequently in the more severe cases, but an inferior vena cava filter was the only management strategy that reduced the mortality from APE. CONCLUSIONS: The severity of APE at diagnosis affected the selection of both the diagnostic techniques and the type of management. Implantation of inferior vena cava filters reduced the mortality from APE.  相似文献   
536.
OBJECTIVE: We aimed to determine the serum level of fibroblast growth factor-23 (FGF-23) in patients with primary hyperparathyroidism (pHPT) to understand its physiological role in the disorder. PATIENTS AND METHODS: Ninety-eight patients with pHPT who underwent parathyroidectomy formed the study group. We also measured serum FGF-23 in 11 of these patients on postoperative day 6. RESULTS: Serum FGF-23 levels was significantly higher in pHPT patients than in healthy controls (35.6+/-17.8 ng/l vs 28.9+/-11.2 ng/l (mean+/-s.d.); P<0.001 (Pearson's correlation coefficient)), but there was no significant difference in the serum FGF-23 level between pHPT patients with normal renal function (creatinine clearance (Ccr) of >or=70 ml/min) and healthy controls. Serum FGF-23 correlated positively with serum calcium (P<0.0001) and intact parathyroid hormone (PTH) (P<0.01), and negatively with Ccr (P<0.001), serum phosphate (P<0.05), and serum 1,25-dihydroxyvitamin D (1,25(OH)(2)D) (P<0.05). Multiple linear regression analysis of factors potentially determining serum FGF-23 levels in pHPT patients showed serum calcium (P<0.01) and Ccr (P<0.001) to be significant predictors. The serum levels of FGF-23 did not change after parathyroidectomy despite the normalization of serum calcium values. Multiple linear regression analysis revealed that serum FGF-23 was not a significant predictor of serum phosphate or 1,25(OH)(2)D in pHPT patients. CONCLUSIONS: FGF-23 may not play a significant role in regulating phosphate or 1,25(OH)(2)D in pHPT patients, especially in those with normal renal function. Further studies are warranted to determine the role of FGF-23 in renal insufficiency or failure.  相似文献   
537.

Background

The NupulseCV intravascular ventricular assist system (iVAS), which consists of a durable pump placed through the subclavian artery, provides extended-duration ambulatory counterpulsation. This study investigated the effect of iVAS on biventricular cardiac function.

Methods and Results

We reviewed all heart failure patients who received iVAS implantation as a bridge to transplantation or a bridge to candidacy since April 2016 as part of the iVAS first-in-humans and subsequent feasibility study. We compared data of transthoracic echocardiography performed just before implantation (without iVAS support) and again at 30 days or just before explantation (on iVAS support). Eighteen patients (58.8 ± 7.4 years old and 15 male) received iVAS support for 53 ± 43 days. Fourteen patients were bridged to cardiac replacement therapy after 35 ± 19 days and the remaining 4 patients had been supported for 118 ± 41 days. There were no deaths during iVAS support. At 30 days, there was a significant improvement in left ventricular ejection fraction (16.5% ± 11.9% vs 24.4% ± 12.8%; P?=?.007) and marked reduction in left atrial size (62.7 ± 35.7 mL/m2 vs 33.8 ± 17.2 mL/m2; P < .001). Right ventricular fractional area change improved dramatically (25.4% ± 12.9% vs 42.1% ± 12.4%; P < .001). All other right ventricular and right atrial parameters improved significantly as well (size, tricuspid annular plane systolic excursion, and velocity of tricuspid annular systolic motion).

Conclusions

Improvement in biventricular cardiac function was observed after 30 days of iVAS support. Further studies should examine the use of this technology as a bridge to recovery.  相似文献   
538.

Background

The assessment of hemodynamics in patients supported with left ventricular assist devices (LVADs) is often challenging. Physical examination maneuvers correlate poorly with true hemodynamics. We assessed the value of novel transthoracic echocardiography (TTE)–derived variables to reliably predict hemodynamics in patients supported with LVAD.

Methods and Results

A total of 102 Doppler-TTE images of the LVAD outflow cannula were obtained during simultaneous invasive right heart catheterization (RHC) in 30 patients supported with continuous-flow LVADs (22 HMII, 8 HVAD) either during routine RHC or during invasive ramp testing. Properties of the Doppler signal though the outflow cannula were measured at each ramp stage (RS), including the systolic slope (SS), diastolic slope (DS), and velocity time integral (VTI). Hemodynamic variables were concurrently recorded, including Doppler opening pressure (MAP), heart rate (HR), right atrial pressure, pulmonary artery pressure, pulmonary capillary wedge pressure (PCWP), Fick cardiac output (CO) and systemic vascular resistance (SVR). Univariate and multivariate regression analyses were used to explore the dependence of PCWP, CO, and SVR on DS, SS, VTI, MAP, HR, and RS. Multivariate linear regression analysis revealed significant contributions of DS on PCWP (PCWPpred?=?0.164DS?+?4.959; R?=?0.68). Receiver operating characteristic (ROC) curve analysis revealed that PCWPpred could predict an elevated PCWP ≥18 mm Hg with a sensitivity (Sn) of 94% and specificity (Sp) of 85% (area under the ROC curve 0.88). CO could be predicted by RS, VTI, and HR (COpred?=?0.017VTI?+?0.016HR?+?0.12RS?+?2.042; R?=?0.61). COpred could predict CO ≤4.5 L/min with Sn 73% and Sp 79% (AUC 0.81). SVR could be predicted by MAP, VTI, and HR (SVRpred?=?15.44MAP???5.453VTI???6.349HR?+?856.15; R?=?0.84) with Sn 84% and Sp 79% (AUC 0.91) to predict SVR ≥1200 dyn-s/cm5.

Conclusions

Doppler-TTE variables derived from the LVAD outflow cannula can reliably predict PCWP, CO, and SVR in patients supported with LVADs and may mitigate the need for invasive testing.  相似文献   
539.

Background  

To develop a new endoscope for performing simple surgical tasks inside the blood-filled cardiac atrium/chamber, that is, “off-pump” cardiac surgeries.  相似文献   
540.
Mucosa-associated lymphoid tissue (MALT) lymphoma arising in the thymus is extremely rare and little is known regarding its clinicopathological features. This study examined the clinicopathological features of nine cases of thymic MALT lymphoma. Most patients had autoimmune disease or hyperglobulinemia, and they also had cysts in the tumors. Both increased serum autoantibody levels and polyclonal serum immunoglobulin levels remained essentially unchanged after total thymectomy in all patients. Thymic MALT lymphoma needs to be included in the differential diagnosis in Asian patients with a cystic thymic mass accompanied by autoimmune disease or hyperglobulinemia.  相似文献   
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