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91.
92.
Abstract: The expression of human regulators of complement activation in endothelium of a transplanted organ is an approach to overcoming the complement (C)-mediated rejection of a xenograft. We designed a replication-deficient adenovirus (Ad) containing the human CD59 cDNA (AdCD59) in order to induce expression of human CD59 on xenogeneic endothelial cells (EC) and confer protection against human C-mediated lysis. In vitro transduction of rat EC with AdCD59 led to consistent levels of CD59 expression in all cells and significantly reduced EC lysis induced by human xenogeneic natural antibodies (XNA) binding and C activation. In addition, we analyzed whether Ad transduction had modified the phenotype of EC and the xenogeneic recognition of EC by human serum. For this, we first demonstrated that transduction of rat EC with AdCD59 or an Ad carrying the lacZ gene (AdlacZ) markedly enhanced the expression of some cell-membrane markers of EC activation, including class I MHC antigens and rat CD59, to levels comparable to those obtained with TNFα Up-regulation of class I MHC antigens was observed for both mRNA and protein expression. In contrast, AdCD59-mediated gene transfer slightly increase intercellular adhesion molecule-1 (ICAM-1) and did not modify the expression of Crry, a rat complement regulatory molecule. Second, we showed that these phenotypic modifications of EC did not affect the expression of the Galαl-3Gal epitope and the binding of human XNA. In addition, neither AdlacZ-mediated transduction, nor TNFα treatment, modified the sensitivity of xenogeneic EC to human serum-mediated lysis. In conclusion, this study demonstrated that transduction of human CD59 with an adenoviral vector conferred resistance to xenogeneic cultured EC against human C-mediated lysis but is associated with cellular activation of transduced EC. This finding may have important implications for the in vivo protocols and strategies intended to generate safer Ad vectors.  相似文献   
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Joseph Alcalay  MD    Ronen Alkalay  MD    rea Gat  MD    Shmuel Yorav  MD 《Dermatologic surgery》2003,29(8):859-862
BACKGROUND: Artecoll is permanent filler that is used for the correction of facial wrinkles. It has been used mainly in Europe in the last 9 years. It is a suspension of 25% polymethylmethacrylate microspheres of 30 to 40 microns in diameter and 75% athecollagen. OBJECTIVE: To report a side effect of a late-onset granulomatous reaction to Artecoll. METHODS: We report the case of a 54-year-old woman who presented with longitudinal hard nodules with slight overlying erythema in the glabella and nasolabial folds 14 months after she was treated with Artecoll injections to her glabellar and nasolabial wrinkles. An excisional biopsy of a glabellar nodule was performed. RESULTS: Microscopic examination of hematoxylin and eosin-stained specimen revealed histiocytic granulomas with giant cells and vacuoles, a picture of Artecoll granulomas. Treatment with topical steroids showed no improvement. Intralesional injections of Kenalog caused temporary disappearance of the granulomas. A few months later the nodules reappeared. No further treatment was done. CONCLUSION: Artecoll injection to wrinkles of the face can cause delayed granulomatous reaction. This side effect is not reversible and should be addressed in the informed consent.  相似文献   
95.
Hepatocytes transplantation is viewed as a possible alternative or as a bridge therapy to liver transplantation for patients affected by acute or chronic liver disorders. Very few data regarding complications of hepatocytes transplantation is available from the literature. Herein we report for the first time a case of portal vein thrombosis after intraportal hepatocytes transplantation in a liver transplant recipient. A patient affected by acute graft dysfunction, not eligible for retransplantation, underwent intraportal infusion of 2 billion viable cryopreserved ABO identical human allogenic hepatocytes over a period of 5 h. Hepatocytes were transplanted at a concentration of 14 million/ml for a total infused volume of 280 ml. Doppler portal vein ultrasound and intraportal pressure were monitored during cell infusion. The procedure was complicated, 8 h after termination, by the development of portal vein thrombosis with liver failure and death of the patient. Autopsy showed occlusive thrombosis of the intrahepatic portal vein branches; cells or large aggregates of epithelial elements (polyclonal CEA positive), suggestive for transplanted hepatocytes, were co-localized inside the thrombus.  相似文献   
96.
Fish is an important item in the diet of Amazonians, and per se is their best single source of essential nutrients. Rapid urbanization and migration are bringing changes in dietary habits of Amazonians. Exposure to fish-Hg during pregnancy and lactation were studied in 100 women and newborns from Porto Velho. Tissue-Hg concentrations and neurodevelopment (Gesell Developmental Schedules) were assessed at birth and at 6 months in exclusively breastfed infants. Maternal mean frequency of fish consumption was low (<2 meals/week; range 0->7 meals/week) compared to Amazonian standards. Women consuming <2 fish meals/week showed less median hair-Hg (3.5 microgg-1) than women that consumed 2 fish meals/week (5.7 microgg). Median total Hg in maternal hair (5.4 microgg-1) was higher than in newborns (1.6 microgg-1). Significant correlation was observed between maternal hair-Hg and infant hair-Hg at birth (r=0.353; p<0.01) and at six months (r=0.510; p<0.01). Placenta-Hg was also significantly correlated to maternal hair-Hg (r=0.321; p<0.01), newborn hair-Hg (r=0.219; p<0.05), maternal blood-Hg (r=0.250; p<0.01) and to umbilical cord-Hg (r=0.857; p<0.01). Most infants (74%) had normal Gesell Schedules but among the 26% showing neuro-motor development delays only six (7%) had multiple (motor, language, and adaptative) delays. The infants with multiple delays were born from mothers with range of hair-Hg comparable to mothers of normally developed infants. Coincidentally, mothers of infants with multiple delays also showed the lowest range of income and level of education. Fish consumption, income, and level of education varied greatly among these breastfeeding urban mothers. It seems that development delays of exclusively breastfed infants are a component of the health inequalities that accompanies socioeconomic disadvantages.  相似文献   
97.
BACKGROUNDSarcopenia is a condition characterized by decreased skeletal muscle mass due to physiological ageing or to a concomitant disease such as neoplasia. In cancer patients, a low lean body mass is suggested to be a negative prognostic factor for survival and for the development of dose-limiting chemotherapy toxicities irrespective of disease stage. AIMTo evaluate the prognostic role of sarcopenia in patients with metastatic colorectal cancer (mCRC) undergoing first-line chemotherapy.METHODSOur retrospective analysis included 56 mCRC patients who received first-line chemotherapy from 2014 to 2017 at the Medical Oncology Unit of our hospital. Computerized scans were performed before starting chemotherapy and at the first disease reassessment. Sarcopenia was assessed using the skeletal mass index = muscle area in cm2/(height in m2) calculated at the L3 vertebra. Overall survival and objective response rate were evaluated. Toxicities were analyzed during the first four cycles of therapy and graded according to Common Terminology Criteria for Adverse Events version 4.0. A loss of skeletal muscle mass ≥ 5% was considered indicative of deterioration in muscle condition.RESULTSMedian age was 67 years and 35.7% of patients were ≥ 70 years old. Fourteen patients (25%) were sarcopenic at baseline computed tomography (CT) scan (7/33 men; 7/23 women); 5/14 sarcopenic patients were ≥ 70 years old. Median follow-up was 26.8 mo (3.8-66.8 mo) and median overall survival was 27.2 mo (95%CI: 23.3-37.3). Sarcopenia was not correlated to overall survival (P = 0.362), to higher toxicities reported during the first 4 cycles of chemotherapy (P = 1.0) or to response to treatment (P = 0.221). At the first disease reassessment, a skeletal muscle loss (SML) ≥ 5% was found in 17 patients (30.3%) 3 of whom were already sarcopenic at baseline CT scan, while 7 patients became sarcopenic. SML was not correlated to overall survival (P = 0.961). No statistically significant correlation was found between baseline sarcopenia and age (P = 1.0), body mass index (P = 0.728), stage at diagnosis (P = 0.355) or neutrophil/lymphocyte ratio (P = 0.751).CONCLUSIONNeither baseline sarcopenia nor SML affected survival. In addition, baseline sarcopenia was not related to worse treatment toxicity. However, these results must be interpreted with caution due to the limited sample size.  相似文献   
98.
To assess the biological correlates of the precipitation of migraine attacks in the perimenstrual period, plasma beta-endorphin (beta-EP) and cortisol responses to naloxone (8 mg iv) and corticotropin releasing hormone (100 micrograms iv) were evaluated in both the follicular phase and the premenstrual period in 7 patients suffering from menstrual migraine and in 7 healthy, asymptomatic control volunteers. In the controls, naloxone evoked a significant release of both beta-EP (F = 5.86, p less than 0.002) and cortisol (F = 4.43, p less than 0.008), independently of the menstrual cycle phase (F = 0.31 and 1.04, for beta-EP and cortisol, respectively). Menstrual migraine patients, on the other hand, showed a significant hormone response only in the follicular phase, not in the premenstrual period. Corticotropin releasing hormone significantly increased beta-EP and cortisol in both the controls and the menstrual migraine patients, independently of the menstrual cycle phase. In both the naloxone and corticotropin releasing hormone testings, the basal beta-EP levels measured in the premenstrual period were lower than those observed in the follicular phase (p less than 0.02). These data demonstrate a cyclical, premenstrual dysfunction of the hypothalamic control exerted by opioids on the hypothalamus-pituitary-adrenal axis. Impairment of this fundamental adaptive mechanism (involved in stress responses and in pain control) could establish a causal relationship between menstrual-related migraine attacks and premenstrual opioid hyposensitivity.  相似文献   
99.
Chronic alcoholics demonstrate cognitive deficits when compared with nonalcoholics. These deficits are typically attributed to the direct effects of ethanol and its metabolites on the central nervous system (CNS). There are other factors, however, that differentiate alcoholics from controls, such as personality or behavioral characteristics. These factors may affect neuropsychological performance and thus alter the interpretation of alcoholic cognitive deficits as resulting solely from alcohol's toxic effects. To investigate this question, male and female alcoholics and peer nonalcoholic controls were compared on personality, behavioral, and cognitive measures. Alcoholics had greater numbers of antisocial behaviors, childhood behavioral disorder symptoms (CBD), and affective symptomatology, and had poorer neuropsychological performance than controls. The three personality and behavioral factors were positively intercorrelated with each other, and were negatively related to cognitive performance. The CBD factor proved to be the most consistent predictor of neuropsychological performance for both alcoholics and controls, and males and females. While the behavioral factors differentiated alcoholics from controls and predicted performance, significant differences between the groups in cognitive performance still remained when these factors were taken into account.  相似文献   
100.
BACKGROUND: Recombinant human erythropoietin (rhEPO) increases blood pressure (BP) and the vascular production of endothelin-1 in renal failure rats. This study was designed to investigate the effect of rhEPO on BP and on the ET-1/ET(B)R system in rats with normal renal function. To further characterize the effect of rhEPO on the ET-1/ET(B)R system, we also studied heterozygous (+/-) ET(B)R knockout (KO) mice. METHODS: The animals received either the vehicle or rhEPO (100 U/kg subcutaneously three times per week). ET(B)R(+/-) mice were compared with ET(A)R(+/-) and wild-type (WT) mice. In rats, the ET(B)R mRNA expression was assessed in blood vessels as well as the vascular ET(B)R density using immunohistochemistry. In mice, ET-1 concentration was measured in the thoracic aorta. RESULTS: RhEPO administration increased hematocrit levels in all treated animals. This therapy had no effect on BP in normal rats, but it did increase vascular and renal cortex ET(B)R mRNA expression. Immunohistochemistry confirmed that the ET(B)R density was increased in blood vessel endothelium in these normal rats. In contrast, rhEPO increased BP in ET(B)R(+/-) mice and this pressor effect was associated with higher ET-1 concentrations in the thoracic aorta. CONCLUSIONS: RhEPO exerts a pleotropic effect on the endothelial ET-1/ET(B)R system. The increase in endothelial ET(B)R expression may contribute to maintaining normal BP during rhEPO administration in normal animals. Conversely, conditions with deficient ET(B)R expression, such as in ET(B)R(+/-) mice, may lead to hypertension while receiving the same therapy.  相似文献   
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