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51.
52.
JB Fregoneze H Ferreira T Soares CP Luz C Bulc?o T Nascimento CA Marinho C Sarmento IR De-Oliveira M Cunha 《Canadian Metallurgical Quarterly》1995,28(6):711-714
Zinc is found in many brain regions where it participates in important processes such as neurotransmission and neuromodulation. We previously demonstrated that acute third ventricle injection of zinc inhibits water intake in dehydrated rats. The present study was undertaken to explore a possible link between zinc-induced inhibition of water intake in dehydrated rats and serotonergic systems in the brain. Adult, male Wistar rats had the third ventricle cannulated a week before the experiments. After an overnight period of water deprivation, the animals (N = 12 per group) received acute intracerebroventricular injections (2 microliters) of Zn(Ac)2 (6.7, 67.1 and 671.6 ng/rat). Control animals (N = 12) received NaAc (671.6 ng/rat). Zinc-treated animals displayed a significant, dose-dependent reduction in water intake. Water intake after 120 min was 7.70 +/- 0.50 ml in control (NaAc-treated) dehydrated rats while animals treated with the highest dose of Zn(Ac)2 drank 2.63 +/- 0.73 ml. Third ventricle injections of SDZ 216-525, a selective 5-HT1A receptor antagonist, 45 min before zinc administration, generated a dose-dependent reversal of zinc-induced thirst blockade in water-deprived rats. At the highest dose used (10 micrograms/rat), the water intake of the animals after 120 min was 7.30 +/- 0.23 ml, a value equal to that of control animals. These data suggest that zinc may decrease water intake in dehydrated rats by activation of a 5-HT1A receptor-related mechanism. 相似文献
53.
EM Conill CA Pieralisi MA Peres C Castilhos AB Ortiga TT Li S Nascimento 《Canadian Metallurgical Quarterly》1998,14(4):857-861
This study describes the 'Law Court' technique as applied to City Health Departments in the State of Santa Catarina, in dealing with the issue of obligations on the part of public officials. The project was the first part of a training course for public administrators held in 1997. The article presents the technique's components and results. Some 98% of the 156 participants had a positive opinion of the training course, considering it dynamic/participatory (31%), educational/stimulating reflection (27%), and realistic (24%). The technique fostered the discussion of the main subjects pertaining to the country's Unified Health System (SUS). Although all five juries acquitted the defendants, the issue of ethics was reported by 58% of the participants as the main prerequisite for a public administrator. 相似文献
54.
CA Arndt AG Nascimento G Schroeder PJ Schomberg JP Neglia SF Sencer TL Silberman CL Moertel JK Tillisch JS Miser 《Canadian Metallurgical Quarterly》1998,34(8):1224-1229
Over 50% of patients with newly diagnosed rhabdomyosarcoma (RMS) are in the 'intermediate risk' group with a 3-year progression-free survival of approximately 65%. This group consists of stage 1, group III, non-orbit tumours; stage 2, group II and III; and all stage 3 patients utilising the Intergroup Rhabdomyosarcoma Study (IRS) staging system. The role of doxorubicin in the treatment of RMS has been controversial. Ifosfamide, both alone and in combination with etoposide, has significant activity in patients with RMS. The aim of this pilot study was to examine the efficacy and toxicity of a chemotherapy regimen of alternating cycles of vincristine/doxorubicin/cyclophosphamide and etoposide/ifosfamide for intermediate risk RMS. 30 patients with intermediate risk RMS or undifferentiated sarcoma (US) were treated with alternating cycles of vincristine/doxorubicin/cyclophosphamide (VDC) and etoposide/ifosfamide (EI) at planned intervals of 3 weeks. Local treatment of the tumour in most cases was performed after four cycles of chemotherapy, followed by an additional 10 cycles of chemotherapy. At a median follow-up of 37.5 months, the Kaplan-Meier estimate of 3-year event-free survival was 85% (95% confidence interval 72-99%). The overall survival at 3 years was 91% (95% confidence interval 80-100%). No patient died from toxicity. The most common toxicity was febrile neutropenia in 35% of VDC and 26% of EI cycles. No nephrotoxicity or cardiac toxicity was seen. No patient progressed prior to week 12 local therapy. Alternating cycles of VDC and EI are an effective treatment for patients with intermediate risk RMS and US. Toxicity is tolerable. Delaying local treatment until week 12 does not compromise outcome. 相似文献
55.
EA Nascimento FA Tonon AM Kelmer-Bracht A Bracht EL Ishii-Iwamoto 《Canadian Metallurgical Quarterly》1997,96(2):193-201
To better understand the characteristics of amyloid deposition in the choroid plexus, we examined autopsied brain by routine histology, immunohistochemistry, and electron microscopy in three group of patients: primary systemic amyloidosis (n = 7), cerebral amyloid angiopathy (CAA, n = 6), and controls (n = 3). Three of the CAA patients had Alzheimer's disease. Congophilic, birefringent amyloid deposits of the choroid plexus were seen in six of the seven cases of systemic light chain amyloidosis. Immunohistochemistry revealed that the deposited amyloids had reactivity for immunoglobulin light chain and amyloid P component. Accumulation of macrophages labeled with monoclonal antibodies against CD 68 and major histocompatibility complex class II antigens were observed around the massive amyloid deposits. The presence of approximately 10 nm amyloid fibrils along the epithelial basement membrane as well as in the vascular walls was ascertained by electron microscopy. In CAA, Congo red-positive amyloid deposits were consistently present in meningeal blood vessels and were often found in senile plaques of the cerebral parenchyma; congophilic amyloid deposits were absent in the choroid plexus. Choroid plexus epithelial cells exhibited immunostaining for beta amyloid precursor protein (APP) with N-terminal- and C-terminal-specific antibodies; in particular, consistent staining was obtained for the latter antibody. Immunoreactivity for amyloid beta protein (A beta) with monoclonal antibodies (6E10, 4G8) was often found in choroid plexus epithelial cells. These findings suggest that amyloid deposition of the choroid plexus depends on the major component protein in amyloidosis, and that the choroid plexus may produce APP and A beta protein although A beta amyloidosis is not evident in the choroid plexus. 相似文献
56.
Francisco?Wendel?B.?Aquino Sueli?RodriguesEmail author Ronaldo?F.?Nascimento Ant?nio?Renato?S.?Casimiro 《European Food Research and Technology》2005,221(6):739-745
In response to the increasing demand for aged distilled spirits, wood extracts have been investigated as accelerating agents
in distilled spirits. The aim of this work was to obtain and to evaluate the potential use of Amburana cearensis powder extracts as an accelerating aging agent in sugar cane distilled spirits. Wood powder was submitted to different toasting
treatments using conventional drying oven and microwave oven. Instead of using the traditional reflux extraction method, the
phenolic compounds were extracted by means of ultrasonic treatment using a 50% ethanolic solution with pH adjusted to 4.5.
The concentration of gallic acid, 5-hydroxymethylfurfural, furfural, vanillic acid, syringic acid, vanillin, coniferaldehyde,
sinapaldehyde and coumarin, determined by high performance liquid chromatography (HPLC) were used as quality parameters of
powder toasting treatment and ethanolic extraction. The use of toasted wood powder combined with ultrasonic extraction showed
higher yields when compared to the traditional solvent extraction method when obtaining wood extracts. The extraction method
presented in this work is also less time consuming. 相似文献
57.
Francelino MR Mendonça AL Do Nascimento RR Sant'ana AE 《Journal of chemical ecology》2006,32(3):643-656
The mandibular gland secretions of worker castes from wild colonies of the leaf-cutting ants Atta sexdens sexdens and Atta opaciceps were analyzed quantitatively by gas chromatography–mass spectrometry. The secretions comprised a complex mixture of volatile, mainly oxygenated compounds, and their profiles exhibited considerable qualitative and quantitative variations among species and castes. The known alarm pheromone 4-methyl-3-heptanone was common to both species. The elevated relative proportions of this ketone found in the secretions of gardeners and generalists suggest that such castes are primarily responsible for the production and release of the alarm pheromone. Quantitative variations (but no qualitative differences) in the profiles of secretions of soldiers from different colonies of A. sexdens sexdens were detected, supporting the view that intraspecific colony recognition is mediated through mandibular gland secretions. Subsequent laboratory assays showed that, among the compounds identified by GC–MS, 4-methyl-3-heptanone elicited a strong alarm response in workers of A. sexdens sexdens and A. opaciceps. 相似文献
58.
Yamba Carla Lara Pereira Glauce Crivelaro Nascimento Daniela Mizusaki Iyomasa Rodrigo Alberto Restrepo Fernndez Ricardo Alexandre Calzzani Christie Ramos Andrade Leite‐Panissi Pedro Duarte Novaes Mamie Mizusaki Iyomasa 《Microscopy research and technique》2019,82(5):530-537
Stress is associated with orofacial pain sensitivity and is qualified as a temporomandibular disorder risk factor. During stressful periods, painful thresholds of masticatory muscles in individuals suffering muscle facial pain are significantly lower than in controls, but the exact physiologic mechanism underlying this relation remains unclear. Our hypothesis is that chronic unpredictable stress and masticatory hypofunction induce morphologic and metabolic masseter muscle changes in rats. For test this hypothesis, adult Wistar rats were submitted to chronic unpredictable stress and/or exodontia of left molars and the left masseter muscle was removed for analysis. The parameters evaluated included ultrastructure, oxidative level, metabolism activity and morphological analysis in this muscle. Our data show by histological analysis, that stress and exodontia promoted a variation on diameters and also angled contours in masseter fibers. The masticatory hypofunction increased oxidative metabolism as well as decreased reactive species of oxygen in masseter muscle. The ultrastructural analysis of muscle fibers showed disruption of the sarcoplasmic reticulum cisterns in certain regions of the fiber in stress group, and the disappearance of the sarcoplasmic reticulum membrane in group with association of stress and exodontia. Our findings clarify mechanisms by which chronic stress and masticatory hypofunction might be involved in the pathophysiology of muscular dysfunctions. Masticatory hypofunction influenced oxidative stress and induced oxidative metabolism on masseter muscle, as well as altered its fiber morphology. Chronic stress presented malefic effect on masseter morphology at micro and ultra structurally. When both stimuli were applied, there were atrophic fibers and a complete mitochondrial derangement. 相似文献
59.
Josiane Ferreira da Silva Débora Lemos da Silva Rui Gomes Nascimento Lizzy Ayra Alcântara Veríssimo Cristiane Martins Veloso Renata Cristina Ferreira Bonomo Rafael da Costa Ilhéu Fontan 《应用聚合物科学杂志》2019,136(37):47956
The use of macroporous monolithic matrices in the purification of biocompounds is constantly growing and developing. In this work, the objective was to optimize the quantity of N-acetyl-D-glucosamine (D-GlcNAc) immobilized on the surface of macroporous polymeric cryogels for capture of lectins from less clarified solutions. Surface response methodology was applied and it was observed that the immobilization temperature of the glutaraldehyde (GLU) and the D-GlcNAc concentration influenced the amount of sugar immobilized. The matrices produced with 1.1% of allyl glycidyl ether were functionalized by GLU. Optimal maximum condition was obtained with mean value of 160.39 ± 26.38 mg of D-GlcNAc immobilized per gram of dry cryogel. Characterization analyses of the matrices showed that the activation process was effective, maintaining the macroporous structure and physical characteristics. The adsorbents produced were tested for capture of lectins from a crude protein solution of barley. At tested conditions, adsorbent capture around 11% of protein in solution but reduce the hemaglutinating capacity in 40%, demonstrating its selectivity. The cryogels functionalized with D-GlcNAc present potential for use in capture compounds by affinity with carbohydrates, such as lectins. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47956. 相似文献