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51.
Objective: To analyze clinical, laboratory and treatment features associated with death in a childhood-onset SLE population. Patients and methods: Patients with childhood-onset SLE followed at the State University of Campinas, Brazil, between 1980 and 2002 were included. Data on clinical and laboratory features of the disease were collected regularly. Logistic regression was used for analyzing association between clinical and laboratory features and death. Kaplan–Meyer tests were used to estimate the survival curves. Results: Of 61 patients identified, six were lost to follow-up during the first year of disease. The mean follow-up period of the remaining 55 patients was 3.25 years (SD=1.2). Mean SLICC/ACR-DI score was 4.9 (SD=3.4). Death occurred in 12 (21.8%) of 55 patients. Direct causes of death were: infection in six (50%), stroke in four (33.3%), and renal insufficiency in two (16.7%). Five patients (41.7%) died during the first 5 years of disease due to infection. Male gender (p=0.004; OR=9.1; 95% CI=7.6–21.0), infection (p=0.001; OR=4.2; 95% CI=1.6–15.2) and nephritis (p=0.02; OR=2.3; 95% CI=1.3–5.2) were independent factors associated with death in the multivariate analysis. The global survival rate adjusted for duration of disease was 93.9% in the first year of disease, 88.9% in the second year, 80.8% in the fifth year and 48.1% in 20 years of follow-up. When comparing survival curves, male gender, the presence of infection during the course of the disease and the presence of nephritis during follow-up had a worse survival. Conclusion: Male gender, the presence of infection and nephritis were independent risk factors for death in our Brazilian cohort. Damage did not independently influence survival in this study.  相似文献   
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Transient spinal ischemia, a complication associated with aortic cross-clamp may lead to spastic paraplegia. Once fully developed this deficit is permanent. Quantitative histopathological assessments and pharmacological studies show that the ischemic spasticity is secondary to the loss of lumbar GABA and glycinergic inhibitory interneurons. In the present study, we investigated whether human hNT neurons or committed Sprague-Dawley rat spinal neuronal precursors (SNPs) when grafted into previously ischemic spinal segments depleted of inhibitory neurons would restore local inhibitory tone and ameliorate spasticity. Rats with functionally and electrophysiologically defined spasticity that received spinal graft of hNT neurons or neuronal precursors and immunosuppressive treatment displayed a progressive recovery of motor function that correlated with the improvement of otherwise exacerbated peripheral motor response evoked by stimulation of motor cortex. In contrast, in control, medium-injected or oligodendrocyte-grafted animals no significant therapeutic effect was seen. Stereological quantification of grafted neurons revealed 1-2% survival at three months after transplantation. These surviving neurons displayed a robust axo-dendritic sprouting and expression of markers typical of mature neurons including NSE, NeuN and synaptophysin. In both treatment groups a subpopulation of grafted neurons developed GABA immunoreactivity. These data provide evidence that a region specific grafting of hNT neurons or other neuronally committed cells, which have a potential to develop inhibitory neurotransmitter phenotype, represent an effective treatment modality to modulate ischemia-induced spastic paraplegia.  相似文献   
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BACKGROUND: A patient underwent repair of a thoracoabdominal aortic aneurysm. Epidural morphine, 4 mg, was given for pain relief. After anesthesia, the patient displayed lower extremity paraparesis. This effect was reversed by naloxone. The authors sought to confirm these observations using a rat spinal ischemia model to define the effects of intrathecal morphine administered at various times after reflow on behavior and spinal histopathology. METHODS: Spinal cord ischemia was induced for 6 min using an intraaortic balloon. Morphine or saline, 30 microg, was injected intrathecally at 0.5, 2, or 24 h after reflow. In a separate group, spinal cord temperature was decreased to 27 degrees C before ischemia. After ischemia, recovery of motor function was assessed periodically using the motor deficit index (0 = complete recovery; 6 = complete paraplegia). RESULTS: After ischemia, all rats showed near-complete recovery of function by 4-6 h. Intrathecal injection of morphine at 0.5 or 2 h of reflow (but not at 24 h) but not saline caused a development of hind limb dysfunction and lasted for 4.5 h (motor deficit index score = 4-6). This effect was reversed by intrathecal naloxone (30 microg). Intrathecal morphine administered after hypothermic ischemia was without effect. Histopathological analysis in animals that received intrathecal morphine at 0.5 or 2 h after ischemia (but not at 24 h) revealed dark-staining alpha motoneurons and interneurons. Intrathecal saline or spinal hypothermia plus morphine was without effect. CONCLUSIONS: These data indicate that during the immediate reflow following a noninjurious interval of spinal ischemia, intrathecal morphine potentiates motor dysfunction. Reversal by naloxone suggests that this effect results from an opioid receptor-mediated potentiation of a transient block of inhibitory neurons initiated by spinal ischemia.  相似文献   
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To define the effects of chronic spinal exposure to a highly selective partial differential opioid agonist c[DPen(2),DPen(5)]enkephalin (DPDPE), adult beagles were prepared with chronic lumbar intrathecal catheters. Groups of dogs received intrathecal infusions (100 micro l/h) of saline (vehicle), DPDPE 3 mg/ml or 6 mg/ml for 28 days. Over the 28-day period, saline or 3 mg/ml showed minimal changes in neurological function, whereas in the 6 mg/ml animals, prominent hind limb dysfunction evolved over the 28-day interval. Histopathology in control animals displayed a modest pericatheter reaction considered normal for this model. Dogs receiving DPDPE (three of four at 6 mg/ml and one of four at 3 mg/ml) but not saline (zero of four) developed large inflammatory masses (granulomas) in the intrathecal space located proximal to the catheter tip. In these masses, severe chronic inflammatory changes in combination with necrosis and fibrosis was detected. Occasional focal destruction of neuropil was detected also in the adjacent spinal cord parenchyma. These masses contained extensive accumulation of mouse antihuman macrophages (MAC)-positive inflammatory cells expressing tumor necrosis factor-alpha (TNF-alpha), revealing infiltration of macrophages, granulocytes, and monocytes. In separate animals, prepared with dual intrathecal catheters, lumbar CSF was sampled at specified time points following intrathecal bolus (3 mg/ml) and 24 h DPDPE infusion (3 mg/ml and 6 mg/ml). Steady-state cerebrospinal fluid (CSF) DPDPE levels were 18.6 +/- 1.0 and 22.6 +/- 4.0 micro g/ml for 3 mg/ml and 6 mg/ml infusions respectively. These results indicate that this partial differential opioid agonist DPDPE produces a concentration and time-dependent formation of an intrathecal inflammatory mass.  相似文献   
57.
Consensus guidelines developed by an expert panel are helpful to clinicians when there is variation in practice and lack of a firm evidence base for an intervention, such as intraspinal therapy for pain. An internet-based survey of practitioners revealed remarkable variation in practice patterns surrounding intraspinal therapy. This prompted an interdisciplinary panel with extensive clinical experience in intraspinal infusion therapy to evaluate the results of the survey, the systematic reviews of the literature pertaining to this approach, and their own clinical experience with long-term spinal infusions. The panel proposed a scheme for the selection of drugs and doses for intraspinal therapy, and suggested guidelines for administration that would increase the likelihood of a successful outcome. These expert panel guidelines were designed to provide an initial structure for clinical decision making that is based on the best available evidence and the perspectives of experienced clinicians.  相似文献   
58.
We have shown that the epidural (EPI) delivery of morphine encapsulated in multivesicular liposomes (DepoFoam drug delivery system) produces a sustained clearance of morphine and a prolonged analgesia. We have sought to subsequently determine the likelihood of deleterious effects on local tissue of repetitive epidural injections of this encapsulated morphine preparation (C0401). Beagle dogs were prepared according to protocol approved by the Institutional Animal Care and Use Committee under volatile general anesthesia with chronic lumbar EPI catheters and subcutaneous injection ports. Male and female dogs (three groups) received a total of 4 EPI injections at 8-day intervals of 3 mL of C0401 (10 mg/mL morphine) (N = 6), DepoFoam vehicle (N = 6), or 0.9% sodium chloride (N = 6). Following EPI-C0401, but not saline or DepoFoam vehicle, there were transient (< 72 hr) decreases in food consumption, arousal, hindlimb muscle tone, and body temperature. Heart rate was unaltered, but there were modest decreases in blood pressure and respiratory rate, which persisted for 24-72 hr after C0401. No persistent changes in sensory/motor function, body weight, or stool/urine production were observed. Cerebrospinal fluid, blood chemistry, and urinalysis performed at surgery and on the day of sacrifice (24 hr after the last dose) were within normal ranges. Gross pathology at necropsy was unremarkable. Spinal histopathology findings were judged to be minimal (e.g., modest pericatheter inflammation and fibrosis) and present in all dogs. However, a statistical trend in the rank order of pathology scores was noted (Saline < DepoFoam vehicle < C0401). Repeated EPI injection of C0401 at the maximum dose that could be administered (30 mg) resulted in moderate, transient behavioral and physiological effects after each injection, consistent with morphine administration, and a modest effect on cord histopathology. This level of pathology is reflected in the lack of change observed in cerebrospinal fluid and lack of neurological findings. These results suggest that C0401 is without significant pathological effects at this dose after repeated epidural delivery in dogs.  相似文献   
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Intracellular brain pH, cortical blood flow (CBF), and electrocorticograms were recorded in regions of severe and moderate ischemia in 10 control rabbits and 10 rabbits given mannitol, 1 gm/kg, after occlusion of a major branch of the middle cerebral artery. Pooling the data from all 20 animals, preocclusion CBF was 46.4 +/- 3.6 ml/100 gm/min and intracellular brain pH was 7.01 +/- 0.04 (means +/- standard error of the means). Although mannitol administration mildly improved CBF in regions of severe ischemia, this increase was not sufficient to prevent metabolic deterioration as assessed by brain pH. However, in regions of moderate ischemia, CBF improved significantly with mannitol and the gradual decline in brain pH observed in control animals was prevented. For example, in the treated moderate ischemia sites 4-hour postocclusion CBF and pH values were 31.8 ml/100 gm/min and 6.89 +/- 0.09, respectively, as compared to control values of 14.3 ml/100 gm/min and 6.75 +/- 0.06. These results suggest that mannitol may be of benefit in stabilizing regions of moderate, but not severe, ischemia after vessel occlusion.  相似文献   
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