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61.
Congenital absence of the portal vein (CAPV) is a rare malformation of the splanchnic venous system. Although CAPV is usually detected in the pediatric age group, our patient was a 35-year-old woman. She had been diagnosed with CAPV in 1996 when she was 27 years old. In 1998, she was placed on hemodialysis due to chronic renal failure. After several episodes of encephalopathy in 2002, liver transplantation (LT) was recommended to her and her family. Since there was no suitable living donor candidate, she was put on the waiting list for a deceased donor liver transplant in Japan. In 2004, her ammonia level increased to around 300 microg/dl, and she went into a coma lasting for three days. After recovering from this event, she underwent a living domino transplantation using a whole liver donated by a familial amyloid polyneuropathy (FAP) patient. Her portal vein, which had drained directly into the inferior vena cava (IVC), was transected together with a cuff of the IVC wall and anastomosed to the graft liver portal vein in an end-to-end fashion. In conclusion, liver transplantation proved to be a safe and effective way to save this patient and improve her quality of life.  相似文献   
62.
Abstract:  The effects of antibody-mediated rejection on long-term graft survival have not been fully investigated. The aim of this study is to clarify the influence on long-term survival of deposition of the complement split product C4d in allografts using polyclonal anti-C4d antibody. Inclusion criteria were recipients who underwent graft biopsy during acute deterioration of graft function within the first 2 yr after transplantation. Patients whose graft did not survive more than 1 yr and who received graft from an human leucocyte antigen (HLA)-identical sibling or an ABO-incompatible donor were excluded. Among the 92 recipients investigated, 22 (23.9%) had peritubular capillary C4d deposition, 15 (16.3%) had glomerular capillary C4d deposition and seven (7.6%) had both peritubular and glomerular capillary C4d deposition. Twenty of these 22 patients revealed acute cellular rejection, including borderline changes. There was no significant relationship between pathological severity of acute rejection and presence or absence of peritubular capillary C4d deposition. Graft survival was inferior in patients with peritubular capillary C4d deposition to that in patients without C4d deposition (p = 0.0419). Graft survival in patients with glomerular C4d deposition did not differ from that in patients without C4d deposition. In conclusion, C4d deposition in peritubular capillaries has a substantial impact on long-term graft survival.  相似文献   
63.
64.
Osteoclasts are formed from the monocyte-macrophage lineage in response to receptor activator of nuclear factor κB ligand (RANKL) expressed by osteoblasts. Bone is the most common site of breast cancer metastasis, and osteoclasts play roles in the metastasis. The taxane-derived compounds paclitaxel and docetaxel are used for the treatment of malignant diseases, including breast cancer. Here we explored the effects of docetaxel on osteoclastic bone resorption in mouse culture systems. Osteoclasts were formed within 6 days in cocultures of osteoblasts and bone marrow cells treated with 1,25-dihydroxyvitamin D3 plus prostaglandin E2. Docetaxel at 10−8 M inhibited osteoclast formation in the coculture when added for the entire culture period or for the first 3 days. Docetaxel, even at 10−6 M added for the final 3 days, failed to inhibit osteoclast formation. Osteoprotegerin, a decoy receptor of RANKL, completely inhibited osteoclast formation when added for the final 3 days. Docetaxel at 10−8 M inhibited the proliferation of osteoblasts and bone marrow cells. RANKL mRNA expression induced by 1,25-dihydroxyvitamin D3 plus prostaglandin E2 in osteoblasts was not affected by docetaxel even at 10−6 M. Docetaxel at 10−6 M, but not at 10−8 M, inhibited pit-forming activity of osteoclasts cultured on dentine. Actin ring formation and l-glutamate secretion by osteoclasts were also inhibited by docetaxel at 10−6 M. Thus, docetaxel inhibits bone resorption in two different manners: inhibition of osteoclast formation at 10−8 M and of osteoclast function at 10−6 M. These results suggest that taxanes have beneficial effects in the treatment of bone metastatic cancers. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
65.
Purpose  The impact of infliximab (IFX) on postoperative complications in surgical patients with Crohn’s disease (CD) and ulcerative colitis (UC) is unclear. We examined a large patient cohort to clarify whether a relationship exists between IFX and postoperative complications. Methods  A total of 413 consecutive patients—188 (45.5%) with suspected CD, 156 (37.8%) with UC, and 69 (16.7%) with indeterminate colitis—underwent abdominal surgery at the Massachusetts General Hospital between January 1993 and June 2007. One hundred one (24.5%) had received preoperative IFX ≤ 12 weeks before surgery. These patients were compared to those who did not receive IFX with respect to demographics, comorbidities, presence of preoperative infections, steroid use, and nutritional status. We then compared the cumulative rate of complications for each group, which included deaths, anastomotic leak, infection, thrombotic complications, prolonged ileus/small bowel obstruction, cardiac, and hepatorenal complications. Potential risk factors for infectious complications including preexisting infection, pathological diagnosis, and steroid or IFX exposure were further evaluated using logistic regression analysis. Results  Patients were similar with respect to gender (IFX = 40.6% men vs. non-IFX = 51.9%, p = 0.06), age (36.1 years vs.37.8, p = 0.43), Charlson Comorbidity Index (5.3 vs. 5.7, p = 0.25), concomitant steroids (75.3% vs. 76.9%, p = 0.79), preoperative albumin level (3.3 vs. 3.2, p = 0.36), and rate of emergent surgery (3.0% vs. 3.5%, p = 1.00). IFX patients had higher rates of CD (56.4% vs. 41.9%, p = 0.02), concomitant azathioprine/6-mercaptopurine use (34.6% vs. 16.6%, p < 0.0001), and lower rates of intra-abdominal abscess (3.9% vs. 11%, p < 0.05). After surgery, the two groups had similar rates of death (2% vs. 0.3% p = 0.09), anastomotic leak (3.0% vs. 2.9%, p = 0.97), cumulative infections (5.97% vs. 10.1%, p = 1), thrombotic complications (3.6% vs. 3.0%, p = 0.06), prolonged ileus/small bowel obstructions (3.9 vs. 2.8, p = 0.59), cardiac complications (1% vs. 0.6%, p = 0.42), and hepatic or renal complications (1.0 vs. 0.6% p = 0.72). A logistic regression model was then created to assess the impact of IFX, as well as other potential risk factors, on the rates of cumulative postoperative infections. We found that steroids (odds ratio [OR] = 1.2, p = 0.74), IFX (OR 2.5, p = 0.14), preoperative diagnosis of CD (OR = 0.7, p = 0.63) or UC (OR = 0.6, p = 0.48), and preoperative infection (OR = 1.2, p = 0.76) did not affect rates of clinically important postoperative infections. Conclusions  Preoperative IFX was not associated with an increased rate of cumulative postoperative complications. Dr. Sands has received research grants and honoraria for lecturing and consulting from Centocor.  相似文献   
66.
PURPOSE: We investigated the contribution of alpha1-adrenoceptor mechanisms to urethral dysfunction associated with diabetes mellitus (DM) in rats. MATERIALS AND METHODS: Eight weeks after streptozotocin injection (65 mg/kg intraperitoneally) the effects of DM on urethral relaxation mechanisms were evaluated with subjects under urethane anesthesia by simultaneous recordings of intravesical pressure in isovolumetric conditions and urethral perfusion pressure (UPP). RESULTS: In diabetic rats the intravesical pressure thresholds for inducing urethral relaxation and the lowest urethral pressure (UPP nadir) during urethral relaxation were significantly higher by 142% and 86%, respectively, than in normal rats, while baseline UPPs were not significantly different. The mean rate of high frequency oscillations of urethral striated muscle in diabetic rats was also significantly lower by 23% than in normal rats. After alpha-bungarotoxin treatment (333 mug/kg intravenously) to eliminate striated muscle sphincter contractions the SD of baseline UPPs was significantly larger by 93% than in normal rats. Intravenous administration of terazosin (0.4 mg/kg), an alpha1-adrenoceptor antagonist, significantly decreased the UPP nadir, intravesical pressure thresholds inducing urethral relaxation and the SD by 41%, 87% and 138%, respectively, in diabetic rats but not in normal rats. In the 2 groups of animals after alpha-bungarotoxin treatment urethral relaxation during a reflex bladder contraction was inhibited by Nomega-nitro-L-arginine (40 mg/kg intravenously), a nitric oxide synthase inhibitor. CONCLUSIONS: During reflex bladder contractions streptozotocin induced diabetic rats showed smooth and striated muscle dysfunctions of the urethra. The inhibition of alpha1-adrenoceptors, which decreased the UPP nadir and UPP fluctuation, may be useful for treating urethral dysfunction in DM.  相似文献   
67.
BACKGROUND: We previously showed that the content of reticulocyte hemoglobin (CHr) is a reliable measure of iron status in chronic dialysis patients with erythrocytopoiesis. The CHr was significantly correlated with conventional parameters of iron deficiency in dialysis patients. We attempted to utilize the measurement of CHr levels to monitor iron status and clarify the changes in iron levels that occur as renal anemia progresses in patients with chronic renal failure (CRF). METHODS: We measured CHr, iron parameters, and the intrinsic erythropoietin (EPO) concentration in nondialysis CRF patients who visited our outpatient clinic (n=211). Iron deficiency was defined according to the transferrin saturation (TSAT) and ferritin levels. Conventional red blood cell parameters and CHr levels were measured using an ADVIA120 autoanalyzer (Bayer Medical, USA). RESULTS: The mean CHr value of the nondialysis CRF patients (creatinine clearance less than 70 mL/min) was 32.3 pg, which was not significantly different from that of the dialysis patients. Significant correlations were found between CHr and ferritin levels (r=0.042, p<0.0403) and CHr and TSAT levels (r=0.040, p<0.0157). A positive correlation was observed between the CHr and serum creatinine levels. Nondialysis CRF patients treated with recombinant human EPO (rHuEPO) at a dose of 24,000 U/month exhibited lower CHr levels, compared with those of other patients who received less than 24,000 U/month. CONCLUSION: CHr is an easily measurable and trustworthy marker of iron status in nondialysis CRF patients. Moreover, the CHr level was also sensitive to iron alterations in nondialysis CRF patients receiving rHuEPO treatment, and thus, the CHr value could likely provide useful information regarding the need for iron supplementation.  相似文献   
68.

OBJECTIVE

To evaluate whether endothelial dysfunction and hypertension are prevented by trans-cinnamaldehyde (tCA) through the activation of endothelial nitric oxide synthase (eNOS).

METHODS

Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and stimulated with tCA to determine cell viability using the methyl thiazolyl tetrazolium assay. The effect of tCA on nitric oxide (NO) production was determined by diaminofluorescein-dyes in the absence or presence of inhibitors of eNOS, AMPK, PKA, and AKT. The effect of tCA on blood pressure was determined by the tail-cuff method in obesity spontaneous hypertension (SHR. Cg-Leprcp/NDmcr) rats. The phosphorylation of eNOS and protein expression of the insulin-signaling pathway (InsR-IRS1-PI3K-AKT) were measured by western blot.

RESULTS

tCA at concentrations less than 100 did not affect cell viability in cultured HUVECs. Stimulation with tCA promoted NO release in a time-dependent manner compared with the control group. tCA-treated HUVECs also significantly increased AKT-Ser473 and eNOS- Ser1177 phosphorylation. In SHR-CP rats, treatment with tCA at a dose of 40 mg/kg/day for 6 weeks markedly reduced the systolic blood pressure and diastolic blood pressure, increased the phosphorylation of AKT and eNOS, and increased urinary nitric oxidation.

CONCLUSION

tCA attenuated endothelial dysfunction and reduced blood pressure in SHR-CP rats. The underlying mechanisms may involve the increase in AKT and eNOS phosphorylation and the release of eNOS-derived NO.  相似文献   
69.
Early-onset sarcoidosis (EOS) and inheritable Blau syndrome (BS) share characteristic clinical features of juvenile-onset systemic granulomatosis syndrome that mainly affects skin, joints, and eyes. However, no direct evidence has been shown for the possible common origin of these 2 diseases. Recent discovery of CARD15 mutations in BS families encouraged us to investigate similar CARD15 mutations in EOS patients. Among 10 EOS cases retrospectively collected in Japan, heterozygous missense mutations were found in 9 cases; 4 showed a 1000C>T (R334W in amino acid change) that has been reported in BS, 4 showed novel 1487A>T (H496L), 1538T>C (M513T), 1813A>C (T605P), and 2010C>A (N670K), and 1 case showed double 1146C>G (D382E)/1834G>A (A612T) mutations on different alleles. All 6 of these variants of CARD15 showed increased basal nuclear factor (NF)-kappaB activity. These findings indicate that the majority of EOS and BS cases share the common genetic etiology of CARD15 mutations that cause constitutive NF-kappaB activation.  相似文献   
70.
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