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M. Spada W. Petz A. Bertani S. Riva A. Sonzogni M. Giovannelli E. Torri G. Torre M. Colledan B. Gridelli 《American journal of transplantation》2006,6(8):1913-1921
Avoidance of corticosteroids could be beneficial after pediatric liver transplantation (LTx). To test this hypothesis, we performed a randomized prospective study to compare immunosuppression with tacrolimus (TAC) and steroids versus TAC and basiliximab (BAS) after pediatric LTx. Seventy-two patients were recruited, 36 receiving TAC and steroids and 36 TAC and BAS. The primary endpoint was the occurrence of the first rejection episode. Secondary endpoints were the cumulative incidence and severity of rejection, patient and graft survival, and incidence of adverse events. Overall 1-year patient and graft survival rates were 91.4% and 85.5% in the steroid group, and 88.6% and 80% in the BAS group (p = NS). Patients free from rejection were 87.7% in the BAS group and 67.7% in the steroid group (p = 0.036). The use of BAS was associated with a 63.6% reduction in incidence of acute rejection episodes. Overall incidence of infection was 72.3% in the steroid group and 50% in the BAS group (p = 0.035). We conclude that the combination of TAC with BAS is an alternative to TAC and steroid immunosuppression in pediatric LTx, which allows for a significant reduction in the incidence of acute rejection and infectious complications. 相似文献
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Basic fibroblast growth factor mRNA increases in specific brain regions following convulsive seizures. 总被引:8,自引:0,他引:8
Basic fibroblast growth factor (bFGF) is a trophic factor synthesized in the central nervous system (CNS), where it is believed to play a role in neuronal maintenance and repair. Little is known about the regulation of this growth factor in the CNS. To determine whether the expression of the bFGF gene in the brain of adult animals changes in response to alterations of neuronal activity, we examined bFGF mRNA levels in several brain regions of rats experiencing focally-evoked convulsive seizures. Seizures were induced by microinjecting bicuculline unilaterally into an epileptogenic site within the deep prepiriform cortex, area tempestas (AT). By 5 h after initiation of brief limbic motor seizures from AT, there was a four fold increase in the levels of bFGF mRNA in the entorhinal cortex, hippocampus and olfactory bulb, but not in the caudate-putamen. The maximal expression of bFGF mRNA was reached by 10 h after seizure onset. In the same animals, the mRNA encoding nerve growth factor (NGF) was increased in entorhinal cortex and hippocampus, but not in the olfactory bulb. Our results demonstrate that neuronal activity can influence bFGF expression in an anatomically selective fashion and that acute changes in bFGF can occur in the uninjured mature brain. The increase in bFGF expression in response to excessive activation of specific neuronal circuitry may represent an adaptive response to protect against potential injury in those circuits. 相似文献
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M. Riva A. Salmaggi E. Marchioni A. Silvani G. Tomei L. Lorusso R. Merli F. Imbesi A. Russo 《Neurological sciences》2006,27(5):345-351
Abstract Epilepsy in high-grade glioma patients is a major concern, mainly as regards indications to treatment and best choice; toxicities,
and pharmocokinetic and pharmacodynamic interactions of drugs. All these generally unsolved problems complicate patients’
quality of life and interfere with the evaluation of response criteria in clinical trials. A prospective, multicentre data
collection on 132 adult newly diagnosed, histologically proven glioblastomas from 9 Lombardy hospitals collected in the same
database during a one-year period was recently published. From this database we report epidemiological and clinical characteristics
in epilepsy-symptomatic (31%) glioblastoma patients vs. the group with other presenting symptoms (69%). We analyse demographic
and clinico-radiological features, timing of onset and the course of seizures, and modalities of treatment in the two groups
of patients. No statistically significant differences were observed between the two groups as regards age, site of lesion(s),
extent of surgery and survival in relation to anticonvulsant treatment status or pharmacokinetic properties of drugs. 相似文献
6.
We present 2 cases of superficial siderosis of the central nervous system secondary to chronic subarachnoid bleeding. The diagnosis was made with MR and cerebrospinal fluid (CSF) examination. MR showed, in T2-weighted images, superficial hypointensity of the cervical cord, brainstem, cerebellum, and basal cisterns due to hemosiderin deposits. CSF was xanthochromic, with increased protein content. In 1 of the 2 cases also the CT examination was positive, showing a hyperdense rim around the brainstem. A complete neuroradiological evaluation (MR, CT, angiography and myelography) did not permit to detect the source of the bleeding. 相似文献
7.
Daria L Kring 《Journal of wound, ostomy, and continence nursing》2007,34(4):399-406
Multiple tools have been developed to assist nurses and other care providers to identify and quantify pressure ulcer risk. One of the most widely used tools is the Braden Scale for Predicting Pressure Ulcer Risk. It has been in use for 2 decades and multiple studies have individually reported on its reliability and validity. This article summarizes the reliability and validity of the instrument, and discusses implications for its use in clinical and research settings. The Braden Scale for Predicting Pressure Ulcer Risk has generally performed well in the clinical setting. It has demonstrated reliability and validity in multiple clinical settings, and its parsimonious format enhances incorporation into routine clinical practice. Expanding the instrument may further increase its reliability and validity in the research setting. 相似文献
8.
Altered swelling behavior of femoral cartilage following joint immobilization in a canine model. 总被引:3,自引:0,他引:3
Daria A Narmoneva Herman S Cheung Jean Y Wang David S Howell Lori A Setton 《Journal of orthopaedic research》2002,20(1):83-91
Periods of reduced joint loading have been shown to induce changes in the biochemical composition. metabolism and mechanics of articular cartilage. In this study, changes in cartilage swelling behavior were studied following a 4-week period of joint immobilization, using a recently developed osmotic loading technique [J. Biomech, 32 (1999) 401-408]. The magnitude and distribution of swelling strains were measured in cartilage-bone samples equilibrated in physiological and hypotonic saline, relative to a hypertonic reference NaCl solution. Physicochemical parameters (glycosaminoglycan fixed charge density and water volume fraction) were determined in site-matched cartilage samples. The experimental data for swelling strains, fixed charge density and water volume fraction were used with a triphasic mechano-chemical theory [J. Biomech. Eng. 113 (1991) 245-258] to determine the effect of joint immobilization on the tensile modulus of the cartilage solid matrix. Four weeks of immobilization resulted in a significant increase in the magnitude of swelling-induced strains, and a significant decrease in fixed charge density in cartilage, as compared with the contralateral controls. Joint immobilization also resulted in decreases in values for the modulus of cartilage, as compared with the contralateral controls. Our results suggest that 4 weeks of joint immobilization had a significant effect on cartilage mechanical function that may be linked to collagen changes in the cartilage extracellular matrix. 相似文献
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Autoregulation of human retinal blood flow. An investigation with laser Doppler velocimetry 总被引:7,自引:0,他引:7
C E Riva J E Grunwald B L Petrig 《Investigative ophthalmology & visual science》1986,27(12):1706-1712
The effect of acute changes in mean retinal perfusion pressure, P (2/3 of mean brachial artery blood pressure minus IOP), on retinal volumetric blood flow rate, Q, was investigated in normal volunteers. Changes in Q were determined from Q = k X Vmax X D2, where Vmax is the center line red blood cell velocity measured from temporal veins by laser Doppler velocimetry, D is the vessel diameter obtained by monochromatic fundus photography, and k is a constant of proportionality. A suction cup was used to induce step changes in IOP and, consequently, in P. The magnitude of the steps ranged from 10-32 mmHg. During the first 30 sec after a step decrease in P, Vmax and Q were significantly smaller than at rest by an amount proportional to the decrease in P. Thereafter, Vmax and Q increased markedly towards their values at rest, although P changed comparatively little during this period of time. Time constant of the corresponding decrease in vascular resistance, R(t) = P(t)/Q(t), was approximately 45 sec. There was no significant change in D during elevated IOP. Removal of the cup induced an immediate step increase in P, Vmax, D, Q, and R. Thereafter, Vmax, D, Q, and R returned to their values at rest (time constant of the change in R was about 30 sec), while P remained nearly constant. The rapid change in vascular resistance following a step decrease and increase in P can be attributed to an active process that attempts to maintain blood flow close to normal, in spite of changes in perfusion pressure (autoregulation).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献