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1.
PURPOSEWe aimed to evaluate mid- to long-term results of endovascular treatment for portal vein thrombosis (PVT) after living-donor liver transplantation (LDLT).METHODSThirty cases (14 males, 16 females; age range, 0.67–65 years) who underwent endovascular treatment including thrombolysis, angioplasty, stent placement, and/or collateral embolization for PVT after LDLT from 2001 to 2017 were retrospectively reviewed. Clinical and procedural data were collected and analyzed regarding the patency of the PVT site at the last follow-up date (PVT-free persistency) using Log-rank test. Results were considered statistically significant at p < 0.05.RESULTSMedian follow-up was 120 months. The technical success rate was 80% (n=24). Patency rates at 1 week and 1, 3, 6, 12, 36, and 60 months were 73%, 59%, 55%, 51%, 51%, 51%, and 51% for primary patency and 80%, 70%, 66%, 66%, 66%, 61%, and 61% for assisted patency after secondary endovascular treatment. PVT-free persistency rates regarding the subgroups were as follows: children under 12 years vs. adults, 50% vs. 68% (p = 0.42); acute vs. nonacute, 76% vs. 46% (p = 0.10); localized vs. extensive, 90% vs. 50% (p = 0.035); transileocolic approach vs. percutaneous-transhepatic approach, 71% vs. 54% (p = 0.39); and thrombolysis-based treatment vs. non-thrombolysis-based treatment, 71% vs. 44% (p = 0.12), respectively. Among technically successful cases, PVT-free persistency rate was 94% for those with hepatopetal flow in the peripheral portal vein vs. 17% for those without hepatopetal flow (p < 0.001). The only major complication occurring was pleural hemorrhage (n=1). Minor complications (i.e., fever) occurred in 18 patients (60%).CONCLUSIONIn conclusion, mid- to long-term portal patency following endovascular treatment was approximately 50%–60% in PVT patients after LDLT. PVT site patency over three months after the first endovascular treatment, localized PVT, and hepatopetal flow in the peripheral portal vein were identified as key prognostic factors for mid- to long-term portal patency.

Portal vein thrombosis (PVT) is a vascular complication of living-donor liver transplantation (LDLT), with an estimated incidence of up to 4% (1, 2). The risk of vascular complications, including PVT, is higher in LDLT compared with conventional deceased-donor liver transplantation, because of the smaller vessels, insufficient vessel length for reconstruction, neointimal proliferation, and higher risk of twisting and kinking of the vascular pedicle (3) due to smaller graft size than in deceased-donor liver transplantation. PVT after LDLT can lead to graft failure and the need for retransplantation or death (2), making immediate treatment crucial.Endovascular-based treatment is one option for treating PVT. The utility of target-focused thrombolysis, balloon angioplasty, and stent placement to restore portal flow has been reported previously (410). However, the efficacy of endovascular treatment after LDLT has only been presented in some case reports (11, 12) and the mid- to long-term outcomes remain unclear.The purpose of this study was to evaluate the technical success, feasibility, and mid- to long-term results of endovascular treatment for PVT after LDLT in our institution.  相似文献   
2.
We studied the number and affinity of catecholamine receptors in SD rat kidney by radioreceptor technique. The following conclusions were obtained: 1) By using 3H-prazosin, the numbers of alpha 1-receptor (Bmax) in rat renal cortex were greater than those in rat kidney medulla. As for affinity (Kd), the significance was not recognized between the two. Bmax of the rat renal cortex to 3H-prazosin binding was 96.1 fmol/mg protein, and Kd was 0.17 nM, and for the rat renal medullar these values were 44.5 fmol/mg protein and 0.13 nM, respectively. 2) By measurement of D1-receptor using 3H-SKF38393 in the rat renal cortex in the Scatchard plot analysis, positive cooperativity was observed under the low concentration of hot ligand which was less than 1 nM. But at the concentration of hot ligand over 1 nM, the plots showed a straight line. Bmax of the rat renal cortex to 3H-SKF38393 was 2.5 pmol/mg protein and Kd was 5.3 nM. 3) Based on displacement by dopamine for 3H-prazosin binding to rat renal cortex, it was surmised that high concentration of dopamine had an affinity to alpha 1-adrenoceptors. 4) There was no change in the Kd and Bmax of alpha 1-receptor in the rat renal cortex after incubation of samples with low concentration of dopamine. However, in the case of high concentration of dopamine, a remarkable decrease of the affinity (Kd) of alpha 1-adrenoceptor was observed.  相似文献   
3.
4.
Bronchial venous plexus and its communication with pulmonary circulation   总被引:2,自引:0,他引:2  
This study was undertaken to clarify the microvascular anatomy of the normal human bronchial circulation, focusing on the bronchial venous system and its communication with the pulmonary circulation. Ten normal lungs obtained at autopsy were studied. Bronchial arteriography was performed in six lungs, pulmonary arteriography in two lungs, and pulmonary venography in another two. Using radiologic methods, including microradiography, and serial histologic sections, we found numerous bronchial venous plexuses around the airways and blood vessels into which the bronchial capillaries drained. Frequent communications of the venous plexuses with the pulmonary veins and neighboring alveolar capillaries were also demonstrated. The bronchial venous plexus and its close connection with the pulmonary circulation may be important in various pathologic conditions involving the interstitial space, such as interstitial pulmonary edema.  相似文献   
5.
Ultrasonotomograms of 22 kidneys were obtained in 11 patients with renal-acute renal failure (renal-ARF). The underlying diseases of renal-ARF were acute tubular necrosis in 8 patients and acute on-set chronic glomerulonephritis in 3 patients. They were treated by hemodialysis in 10 patients and intermittent peritoneal dialysis in 1 patient. Ultrasonic measurement of the size of kidneys revealed that the thickness (anterior-posterior diameter) and the ratio of thickness to length (T/L) were greater in patients with ARF than in those with chronic renal failure and normal renal function. The patients with a low value of T/L (under 0.60) had a significantly greater urine volume than those with high a value of T/L (0.60 or more). The sonographic features of renal-ARF kidneys were marked increase in parenchymal echogenicity and appearance of hypoechoic swollen renal pyramids with sharpness of the corticomedullary border. In the course of ARF, these sonographic changes gradually disappeared when the patients had recovered from ARF. However, the prognosis was poor in patients with severer sonographic findings. We believe that repeated ultrasonic examination of the kidneys in patients with renal-ARF is useful for not only differential diagnosis of post-renal urinary obstruction but evaluating the course of ARF.  相似文献   
6.
We examined the relationships between the relaxation mediated by beta-adrenoceptor and either the associated cyclic AMP production or the activation of cyclic AMP-dependent protein kinase (A-PK) in canine saphenous and portal veins. In the saphenous vein constricted with methoxamine, isoproterenol caused concentration-dependent relaxation (maximum relaxation 92.7%), and concomitant increases in cyclic AMP and A-PK activity ratio (from 52.8 to 73.5%). The portal vein was only slightly relaxed by isoproterenol (14.7% in the longitudinal strips) after constriction with methoxamine, while cyclic AMP and A-PK activation increased significantly. Isoproterenol markedly activated A-PK of the portal vein after KCl constriction (from 52.6 to 74.6%) but the maximum relaxation was only slight (13.3%). The portal vein also showed a smaller relaxation response to either forskolin or dibutyryl cyclic AMP than the saphenous vein. These results indicated that the relationship between the relaxation response to isoproterenol and either cyclic AMP production or A-PK activation was different in the saphenous and portal veins.  相似文献   
7.
8.
In order to determine whether or not alpha-adrenoceptors are present in adrenal glands, radioligand receptor binding assay was performed in both Sprague-Dawley (SD) rat and human adrenal gland membranes. Radioligand binding assay using 3H-prazosin as an alpha 1-adrenoceptor ligand and 3H-yohimbine as an alpha 2-adrenoceptor ligand, clearly demonstrated alpha 1 and alpha 2 receptors present in both rat and human adrenal gland membranes. Maximal binding capacity (Bmax) and dissociation constant (Kd) of 3H-prazosin binding to the rat adrenal gland were 12.5 fmol/mg protein, and 0.11 nM, respectively. Those for the membrane preparations from adrenal cortex and medulla of the normal human were 16.3 fmol/mg protein, 0.34 nM and 16.3 fmol/mg protein, 0.27 nM, respectively. And those of the human pheochromocytoma were 25.6 fmol/mg protein, 0.15 nM, respectively. On the other hand, Bmax and Kd of 3H-yohimbine binding in the rat adrenal gland to were 22.9 fmol/mg protein, and 4.28 nM, respectively. Those for the membrane preparations from adrenal cortex and medulla of the normal human were 40.4 fmol/mg protein, 5.15 nM and 12.2 fmol/mg protein, 5.39 nM, respectively. And those of the human pheochromocytoma were 35.8 fmol/mg protein, and 1.08 nM, respectively. Bmax (35.8 fmol/mg protein) of 3H-yohimbine binding in the pheochromocytoma was significantly (p less than 0.01) greater than that (12.2 fmol/mg protein) in the human normal adrenal medulla, while Kd (1.08 nM) of this binding in the human pheochromocytoma was significantly (p less than 0.01) lower than that (5.39 nM) in the human normal adrenal medulla. Our data suggest that the alpha 2 receptor had greater affinity and binding site density to its agonist in the human pheochromocytoma than in the human normal adrenal medulla.  相似文献   
9.
Coronary artery bypass grafting with combined arterial graft using the left internal mammary artery (IMA), right IMA, and the right gastroepiploic artery (GEA) was performed in 45 patients with saphenous vein graft (SVG) (29 patients) or without SVG (16 patients) from February 1989 to October 1989. The left IMA was used in all patients, the right IMA was used in 9 patients, and the GEA was used in 43 patients. Perioperative myocardial infarction was noted in two patients who had hospital deaths. Reopening the chest for postoperative bleeding was performed in two patients, and the cerebral accident was noted in one patient. Fourteen patients were operated on without the requirement for blood transfusion. Studied within 3 postoperative months, all arterial grafts were patent though the patency was 97.7% (43/44) in SVG. It is concluded that the combined arterial graft utilizing the IMAs and GEA can be used safely and effectively.  相似文献   
10.
We report a re-do case of severe aortic valve stenosis due to pannus formation 29 years after an aortic Starr-Edwards caged-ball valve implantation. A huge shelf of calcified and thick pannus tissue below the valve had reduced the already small orifice by at least a third in surface area. The explanted Starr-Edwards valve revealed no mechanical or structural failure. Early detection and treatment of pannus outgrowth is essential in order to prevent life-threatening prosthetic valve malfunctions.  相似文献   
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