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111.
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113.
Spinal neural tube defects are congenital malformations of the spine and spinal cord (eg, myelomeningocele) and are frequently seen in pediatric urology practice. These neurologic problems have many consequences in a child’s life and affect different parts of the body, such as the brain, spinal cord, limbs, bladder, and bowels. Because of the complexity and neurologic aspects of spinal dysraphism, many related terms and aspects of the disease are unfamiliar to the urologist. This review addresses some of the most commonly used neurosurgical terms and concepts related to spinal dysraphism.Key words: Spina bifida, Spinal dysraphism, MyelomeningoceleSpinal neural tube defects are congenital malformations of the spine and spinal cord secondary to abnormal neural tube closure that occur between the third and fourth weeks of gestation. The term spinal dysraphism includes the overall group of defects derived from the maldevelopment of the ectodermal, mesodermal, and neuroectodermal tissues, and its sequelae may affect brain, bones, extremities, and bowel and bladder functions.The incidence of spinal dysraphism ranges from 3.2 to 4.6 per 10,000 births in North America1,2; no geographic variation has been seen, and there is a relatively uniform incidence in all ethnic groups.3 There is strong evidence that there has been a decline in incidence worldwide since the 1970s1,4; however, it is unclear whether this is a transient or permanent trend. This decline is probably due to a systematic use of dietary folic acid before and during the gestational months,5 and more recently to the advent of prenatal diagnosis, which leads to therapeutic abortion in as many as half of the diagnosed cases in some countries.6 The disorder occurs equally or somewhat more commonly in female newborns (female, 1.0–1.7/male, 1.0), depending on the populations studied. Embryologically, open spinal dysraphism (myelomeningocele) is thought to occur 3 to 4 weeks after conception at the time that the neural tube is closing.7Myelomeningoceles are by far the most common spinal dysraphic condition affecting the lower urinary tract and therefore the most familiar to urologists.8 The lumbar and sacral regions are the most common vertebral levels affected9 (
LevelEstimated Prevalence (%)
Cervical0–5
Thoracic5–10
Thoracolumbar20–30
Lumbar20–30
Lumbosacral30–50
Sacral5–15
Open in a separate windowData from Bauer SB et al.9Before advances in ventricular shunting devices, the survival of a child with open spinal dysraphism was dismal, and, therefore, urologic intervention was rarely necessary. As the life expectancy of these children increased, so did the morbidity and mortality secondary to urologic complications, such as pyelonephritis, hydronephrosis, and renal failure.10,11 The need for appropriate urologic evaluation and effective management became mandatory to improve the health, longevity, and quality of life of patients.The evaluation and management of the neurogenic lower urinary tract secondary to spinal dysraphism has undergone a major evolution over the past 30 years.1219 This has been fueled by advances in urodynamic technology and an improved understanding of the long-term effects of a urodynamically hostile bladder and bladder outlet.2022 At the same time, improved methods for maintaining a low-pressure bladder reservoir and providing for adequate emptying through intermittent catheterization has resulted in a marked improvement in prognosis.2334In addition to the urologic problems, patients with spinal dysraphism often have other systemic disorders that require medical attention by a multidisciplinary approach. We focus this article on the premise that a sound understanding of the neurologic aspects of spinal dysraphism will lead to enhanced outcomes for affected children. We discuss neurologic terminology, epidemiology, etiologic risk factors, associated congenital anomalies, prognosis, and appropriate neurosurgical evaluation and management. The urologic evaluation and management of the spinal dysraphic bladder will not be discussed and has previously been extensively reviewed.  相似文献   
114.
The Effects of Estradiol on Estrogen Receptor and Glutamate Transporter Expression in Organotypic Hippocampal Cultures Exposed to Oxygen--Glucose Deprivation     
Cimarosti H  O'Shea RD  Jones NM  Horn AP  Simão F  Zamin LL  Nassif M  Frozza R  Netto CA  Beart PM  Salbego C 《Neurochemical research》2006,31(4):483-490
The molecular basis of estrogen-mediated neuroprotection against brain ischemia remains unclear. In the present study, we investigated changes in expression of estrogen receptors (ERs) α and β and excitatory amino acid transporters (EAAT) 1 and 2 in rat organotypic hippocampal slice cultures treated with estradiol and subsequently exposed to oxygen--glucose deprivation (OGD). Pretreatment with 17β-estradiol (10 nM) for 7 days protected the CA1 area of hippocampus against OGD (60 min), reducing cellular injury by 46% compared to the vehicle control group. Levels of ERα protein were significantly reduced by 20% after OGD in both vehicle- and estradiol-treated cultures, whereas ERβ was significantly up-regulated by 25% in the estradiol-treated cultures. In contrast, EAAT1 and EAAT2 levels were unchanged in response to estradiol treatment in this model of OGD. These findings suggest that estrogen-induced neuroprotection against ischemia might involve regulation of ERβ and, consequently, of the genes influenced by this receptor.Helena Cimarosti and Ross D. O’Shea, equal first authors.  相似文献   
115.
Energy budget of juvenile fat snook Centropomus parallelus fed live food   总被引:1,自引:0,他引:1  
Lemos D  Netto B  Germano A 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2006,144(1):33-40
The fat snook Centropomus parallelus is a tropical estuarine species with importance for recreational and commercial fisheries and further aquaculture potential. Considering ingested energy (C) is channeled into growth (P), metabolic expenditure (R), excretion (U) and feces (F), a balanced energy budget was established for isolated and grouped juvenile C. parallelus (5.18 to 10.25 g wet mass) by experimental quantification of each of these parameters. Fish were fed live prawn (Macrobrachium sp.) at 25 degrees C and 20 per thousand for 19 days and daily energy budgets could be calculated. Energy content of food (live prawn), fish whole body and feces were 17.7, 14.5 and 6.1 KJ g(-1) dry mass (DW), respectively. Mass-specific rates of oxygen consumption and ammonia-N excretion were 0.271 and 0.0082 mg of O(2) or NH(3)-N g(-1) wet mass (WW) h(-1), respectively, resulting in O:N=23.4. Daily ingestion (C) was dependent on the amount of food offered and ranged between 4.9% to 7.4% of initial wet weight. Growth (P) was positively correlated with initial mass varying from 0.008 to 0.104 g day(-1). Feces release also correlated to fish mass and averaged 9.53 mg dry mass day(-1). The components of energy budget showed mean values of 2.39 (C), 0.24 (P), 1.96 (R), 0.11 (U) and 0.06 (F) KJ ind(-1) day(-1). As percentage of ingested energy, C. parallelus channeled 10% in growth (P), 82% in metabolism (R), 4.6% in excretion (U) and 2.5% in feces (F). Gross (K(1)) and net (K(2)) growth efficiencies were 9.2% and 9.9%, respectively. On the course of this period of juvenile development, K(1) and K(2) increased significantly. Partitioning of ingested energy in P, R, U and F was significantly different in individually and group maintained fish (P<0.05). Energy budget of C. parallelus fed a highly digestible diet (live prawn) revealed poor growth and growth efficiencies (K(1) and K(2)) possibly associated with an elevated metabolic demand and a high channeling of metabolized energy (P+R) into metabolism (R) in both isolated and grouped fish. Data can be applied to ecosystem modeling and may contribute to identify species potential to aquaculture.  相似文献   
116.
Simple affinity chromatographic procedure to purify beta-galactoside binding lectins     
De-Simone SG  Netto CC  Silva FP 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,838(2):135-138
Affinity chromatography based on the commercial resin Sepharose CL-6B was used to isolate new C1-beta-type lectins from crude preparations of snake venoms (Bothrops jararaca, Bothrops jararacussu, Bothrops newiedi, Bothrops moojeni, Lachesis muta rhombeata). Most of the C-type lectins could be eluted with almost 100% recovery using the competitor isopropyl-beta-D-thiogalactoside (IPTG) or through Ca2+ sequestration with EDTA. The lectin yield varied considerably among the different snake species, but B. newiedi venom was a particularly rich source of lectin, retaining 2.7 mg of lectin by milliliter of resin in saturating conditions. C1-alpha-lectins from Crotalus durisus terrificus venom, from the jack fruit (jacalin) and from bread fruit seeds extract (frutalin) had no affinity, either with or without Ca2+ added, for Sepharose CL-6B, showing that the resin is specific for C1-beta-type lectins. Sepharose CL-6B used as galactose-affinity chromatography provides a simple and fast method for isolating C-type beta-galactoside binding lectins from crude sample preparations.  相似文献   
117.
1H, 13C and 15N resonance assignments for the reduced forms of thioredoxin 1 and 2 from S. cerevisiae     
Pinheiro AS  Amorim GC  Netto LE  Valente AP  Almeida FC 《Journal of biomolecular NMR》2006,36(Z1):35
  相似文献   
118.
Globotriaosylceramide is correlated with oxidative stress and inflammation in Fabry patients treated with enzyme replacement therapy     
Biancini GB  Vanzin CS  Rodrigues DB  Deon M  Ribas GS  Barschak AG  Manfredini V  Netto CB  Jardim LB  Giugliani R  Vargas CR 《Biochimica et biophysica acta》2012,1822(2):226-232
Fabry disease is an X-linked inborn error of glycosphingolipid catabolism due to deficient activity of α-galactosidase A that leads to accumulation of the enzyme substrates, mainly globotriaosylceramide (Gb3), in body fluids and lysosomes of many cell types. Some pathophysiology hypotheses are intimately linked to reactive species production and inflammation, but until this moment there is no in vivo study about it. Hence, the aim of this study was to investigate oxidative stress parameters, pro-inflammatory cytokines and Gb3 levels in Fabry patients under treatment with enzyme replacement therapy (ERT) and finally to establish a possible relation between them. We analyzed urine and blood samples of patients under ERT (n=14) and healthy age-matched controls (n=14). Patients presented decreased levels of antioxidant defenses, assessed by reduced glutathione (GSH), glutathione peroxidase (GPx) activity and increased superoxide dismutase/catalase (SOD/CAT) ratio in erythrocytes. Concerning to the damage to biomolecules (lipids and proteins), we found that plasma levels of malondialdehyde (MDA) and protein carbonyl groups and di-tyrosine (di-Tyr) in urine were increased in patients. The pro-inflammatory cytokines IL-6 and TNF-α were also increased in patients. Urinary Gb3 levels were positively correlated with the plasma levels of IL-6, carbonyl groups and MDA. IL-6 levels were directly correlated with di-Tyr and inversely correlated with GPx activity. This data suggest that pro-inflammatory and pro-oxidant states occur, are correlated and seem to be induced by Gb3 in Fabry patients.  相似文献   
119.
Exercise impact on sustained attention of ADHD children, methylphenidate effects     
Medina JA  Netto TL  Muszkat M  Medina AC  Botter D  Orbetelli R  Scaramuzza LF  Sinnes EG  Vilela M  Miranda MC 《Attention deficit and hyperactivity disorders》2010,2(1):49-58
Attention deficit hyperactivity disorder (ADHD) is related to a deficiency of central catecholamines (CA) in cognitive, biochemical, and physical tests, and pharmaceutical intervention may have no effect if it is not accompanied by changes in the environment. The objective of our study was to test the hypothesis that central CA are responsible for the increase in speed reaction seen after physical activity (PA) and to measure the impact of high intensity PA on the sustained attention of 25 children diagnosed with ADHD consistent with the Disease Statistical Mental-IV (DSM-IV) criteria. It is possible that practicing sports assists in the management of the disorder. The children were divided between users (US) and non-users (NUS) of methylphenidate (MTP), and the groups were compared to evaluate the effect of the drug on cognition after PA. Post-exercise performance on Conner's Continuous Performance Test-II (CPT) was not affected by MTP, we observed significant improvements in response time, and we saw normalization in the impulsivity and vigilance measures. These results suggest that the improvements in cognition after physical effort are not CA dependent. Additionally, our results suggest that children's attention deficits can be minimized through PA irrespective of treatment with MTP. Additional studies are necessary to confirm that exercise mitigates the harmful symptoms of ADHD.  相似文献   
120.
KIR genes and HLA class I ligands in Gaucher disease     
Filippo Vairo  Pâmela Portela  Patrícia H. Salim  Mariana Jobim  Cristina Netto  Alicia Dorneles  Suzana Mittlestadt  Luiz Fernando Jobim  Ida Vanessa D. Schwartz 《Gene》2013
Gaucher disease (GD) is caused by reduced activity of the lysosomal enzyme glucocerebrosidase, which leads to a buildup of glucocerebroside within the cells and chronic stimulation of the immune system. GD is associated with clinical variability even in the same family, which suggests the influence of modifier genes. Natural killer (NK) cells play an important role in the immune response, and their number is decreased in GD. Killer-cell immunoglobulin-like receptors (KIR) regulate the activity of NK cells through an interaction with specific human leukocyte antigen (HLA) class I molecules on target cells.  相似文献   
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