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排序方式: 共有1661条查询结果,搜索用时 15 毫秒
91.
Donato Rigante Ph.D. M.D. Michele Fastiggi M.D. Francesco Ricci M.D. Francesca D'Errico M.D. Benedetta Bracci M.D. Cristina Guerriero Ph.D. M.D. 《Pediatric dermatology》2017,34(3):235-239
Raynaud's phenomenon (RP) is a vasospastic disorder characterized by recurrent self‐limited episodes of skin pallor, cyanosis, and hyperemia caused by paroxysmal spasms in the small arteries of the fingers and toes and can occur in any age group. Hands, feet, nose, ears, and nipples can be affected. The diagnosis is made clinically, assessing varying degrees of ischemia in the involved areas of skin, but this transient ischemia may also herald the onset of connective tissue disease. Investigation is recommended when RP starts in childhood to exclude an underlying autoimmune condition and close follow‐up for its development. Management of RP in children includes conservative and pharmacologic treatments. 相似文献
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Costanza Sagrinati Mariangela Sottili Benedetta Mazzinghi Elisa Borgogni Luciano Adorini Mario Serio Paola Romagnani Clara Crescioli 《Transplant international》2010,23(9):914-923
During kidney allograft rejection, CXC chemokine ligand 10 (CXCL10)–CXC chemokine receptor 3 (CXCR3) trafficking between peripheral blood and tissues initiates alloresponse and perpetuates a self‐inflammatory loop; thus, CXCL10–CXCR3 axis could represent a pharmacologic target. In this perspective, immunosuppressors targeting graft‐resident cells, beside immune cells, could be very advantageous. Vitamin D receptor (VDR) agonists exhibit considerable immunomodulatory properties. This study aimed to investigate whether elocalcitol and BXL‐01‐0029 could decrease the expression of CXCL10 in activated renal tubular cells in vitro and thus be useful in kidney allograft rejection treatment. Experiments were performed in human tubular renal cells stimulated with interferon‐γ + tumor necrosis factor‐α with and without VDR agonists, tacrolimus, sirolimus, hydrocortisone, methylprednisolone, cyclosporin A and mycophenolate mofetil. CXCL10 protein secretion and gene expression were measured by ELISA and by quantitative PCR. Specific inhibitors were used to investigate intracellular pathways involved in tubular cells activation. For IC50 determination and comparison, dose‐response curves with VDR agonists, tacrolimus and mycophenolic acid were performed. Elocalcitol and BXL‐01‐0029 inhibited CXCL10 secretion by renal cells, without affecting cell viability, while almost all the immunosuppressors were found to be ineffective, except for tacrolimus and mycophenolate mofetil. BXL‐01‐0029 was the most potent drug and, notably, it was found to be capable of allowing reduction in tacrolimus‐inhibitory doses. Our data suggest that BXL‐01‐0029 could potentially be a dose‐reducing agent for conventional immunosuppressors in kidney rejection management. 相似文献
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Mallamaci F Zoccali C Parlongo S Tripepi G Benedetto FA Cutrupi S Bonanno G Fatuzzo P Rapisarda F Seminara G Stancanelli B Bellanuova I Cataliotti A Malatino LS;Cardiovascular Risk Extended Evaluation in Dialysis Investigators 《Kidney international》2002,62(5):1884-1890
BACKGROUND: Cardiac troponin T (cTnT) is related to left ventricular (LV) mass in patients with end-stage renal disease (ESRD). Furthermore, cTnT reflects the severity of systolic dysfunction in patients with heart diseases. We tested the diagnostic value of cTnT for left ventricular hypertrophy (LVH) and LV systolic dysfunction in a large group of clinically stable hemodialysis patients without heart failure. RESULTS: CTnT was significantly (P < 0.001) higher in patients with LVH than in those with normal LV mass. In a multiple logistic regression model, adjusting for potential confounders (including cardiac ischemia), systolic pressure and cTnT (both P = 0.003) were the strongest correlates of LVH. Similarly, cTnT was significantly higher (P = 0.005) in patients with systolic dysfunction than in those with normal LV function and in a multiple logistic regression model cTnT ranked as the second independent correlate of this alteration after male sex. Serum cTnT had a high positive prediction value for the diagnosis of LVH (87%) but its negative prediction value was relatively low (44%). The positive predictive value of cTnT for LV dysfunction was low (25%) while its negative predictive value was high (93%). A combined analysis including systolic pressure (for the diagnosis of LVH) and sex (for the diagnosis of LV systolic dysfunction) augmented the diagnostic estimates to an important extent (95% positive prediction value for LVH and 98% negative prediction value for LV systolic dysfunction). CONCLUSIONS: CTnT has a fairly good diagnostic potential for the identification of LVH and for the exclusion of LV systolic dysfunction in patients with ESRD without heart failure. This marker may be useful for the screening of alterations in LV mass and function in clinically stable hemodialysis patients. 相似文献
96.
Nitric oxide/platelet activating factor cross-talk in mesangial cells modulates the interaction with leukocytes 总被引:13,自引:0,他引:13
BACKGROUND: The secondary hyperparathyroidism of chronic kidney disease (CKD) produces a high turnover osteodystrophy that is associated with peritrabecular fibrosis. The nature of the cells involved in the development of peritrabecular fibrosis may represent osteoprogenitors expressing a fibroblastic phenotype that are retarded from progressing through osteoblast differentiation. METHODS: To test the hypothesis that osteoblast differentiation is retarded in secondary hyperparathyroidism due to CKD producing bone marrow fibrosis, we administered bone morphogenetic protein 7 (BMP-7), a physiologic regulator of osteoblast regulation, to C57BL6 mice that had CKD produced by electrocautery of one kidney followed by contralateral nephrectomy two weeks later. Following the second surgical procedure, a subgroup of mice received daily intraperitoneal injections of BMP-7 (10 microg/kg). Three to six weeks later, the animals were sacrificed, blood was obtained for measurements of blood urea nitrogen (BUN) and parathyroid hormone (PTH) levels, and the femora and tibiae were processed for histomorphometric analysis. RESULTS: The animals had significant renal insufficiency with BUN values of 77.79 +/- 22.68 mg/dL, and the level of renal impairment between the CKD untreated mice and the CKD mice treated with BMP-7 was the same in the two groups. PTH levels averaged 81.13 +/- 51.36 and 75.4 +/- 43.61 pg/mL in the CKD and BMP-7 treated groups, respectively. The animals with CKD developed significant peritrabecular fibrosis. In addition, there was an increase in osteoblast surface and osteoid accumulation as well as increased activation frequency and increased osteoclast surface consistent with high turnover renal osteodystrophy. Treatment with BMP-7 eliminated peritrabecular fibrosis, increased osteoblast number, osteoblast surface, mineralizing surface and single labeled surface. There was also a significant decrease in the eroded surface induced by treatment with BMP-7. CONCLUSIONS: These findings indicate that BMP-7 treatment in the setting of high turnover renal osteodystrophy prevents the development of peritrabecular fibrosis, affects the osteoblast phenotype and mineralizing surfaces, and decreases bone resorption. This is compatible with a role of osteoblast differentiation in the pathophysiology of osteitis fibrosa. 相似文献
97.
Expression of CD154 on renal cell carcinomas and effect on cell proliferation,motility and platelet-activating factor synthesis 总被引:9,自引:0,他引:9
Bussolati B Russo S Deambrosis I Cantaluppi V Volpe A Ferrando U Camussi G 《International journal of cancer. Journal international du cancer》2002,100(6):654-661
CD40 activation by CD154 may trigger diverse cellular responses, ranging from proliferation and differentiation to growth suppression and cell death, in normal and malignant cells. However, the pathophysiologic role of CD154 expressed by tumor cells remains unclear. We have investigated the expression of the CD40-CD154 system in 24 primary cultures derived from renal cell carcinomas, its correlation with tumor stage and its potential functional significance. We found coexpression of CD40 and CD154 in most of the renal carcinoma cell lines. CD154, but not CD40 expression, significantly correlated with tumor stage. Moreover, renal carcinoma cell lines also released the soluble form of CD154 into the supernatant. CD40 engagement by CD154 did not affect apoptosis or survival. On the contrary, CD154 stimulated cell proliferation, motility and production of PAF, a phospholipid mediator of inflammation with angiogenic properties. Furthermore, the renal carcinoma cell lines expressed PAF-R. Blockade of PAF-R by WEB-2170, a PAF-R antagonist, abolished the CD154-dependent motility, indicating a role for PAF synthesized after CD154 stimulation in renal carcinoma cell motility. In conclusion, this study identifies new functional properties for CD154, which are potentially relevant for the growth and dissemination of renal carcinoma cells. 相似文献
98.
Detection of fetal cells in intrauterine lavage samples collected in the first trimester of pregnancy. 总被引:3,自引:0,他引:3
Riccardo Cioni Cecilia Bussani Benedetta Scarselli Francesco Barciulli Sandra Bucciantini Paolo Simi Antonella Fogli Gianfranco Scarselli 《Prenatal diagnosis》2002,22(1):52-55
OBJECTIVES: The aim of the present study was first to evaluate the presence of fetal cells in transcervical cell (TCC) samples collected by intrauterine lavage in the first trimester of pregnancy, and then to compare different methods for the detection of these cells. METHODS: TCC samples were collected by intrauterine lavage before termination of pregnancy (TOP) from 81 pregnant women between 7 and 12 weeks of gestation. Samples of placental tissue were collected from each patient at TOP, whereas maternal peripheral blood samples were obtained in 57 cases. DNA extracted from 81 lavage and the corresponding placental samples was amplified by a polymerase chain reaction (PCR) assay using primers for SRY and HUMARA genes. All 81 lavage samples were also analysed by fluorescent in situ hybridisation (FISH) using direct-labelled probes for X chromosome alpha-satellite (DXZ1, Xp11.1-q11.1) and Y chromosome alpha-satellite (DYZ3, Yp11.1-q11.1) regions. In 57 cases, a quantitative fluorescent (QF) PCR assay, involving the use of two small tandem repeat (STR) markers (D21S11, D21S14.11) specific to chromosome 21 was employed to analyse DNA extracted from placental tissue, lavage and maternal blood samples. RESULTS: PCR analysis revealed that 40/81 placental samples were from male pregnancies. Correct sexing was achieved with the PCR technique in 30/40 (75%) lavage samples retrieved from pregnant women with male conceptuses and in all 41 (100%) samples collected from pregnancies with female fetuses. With the FISH analysis, nuclei bearing X and Y signals were observed in 32/40 cases (80%) from known male pregnancies, the rate of fetal cells ranging between 2% and 95%, whereas nuclei showing X and Y signals were not detected in any of the 41 lavage samples from known female pregnancies. Paternal peaks were present in 30/57 (52.6%) lavage samples tested by QF-PCR. CONCLUSION: The results suggest that fetal cells can be found, at a significant rate, in a very high proportion of intrauterine lavage samples. Therefore, this sampling technique can be regarded as a promising tool towards minimally invasive prenatal diagnosis. The FISH and PCR methods showed a similar efficiency in detecting fetal cells. 相似文献
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