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121.
José De Souza Filho Caio César Neves Sousa Cláudio Carlos Da Silva Simone Maria Teixeira De Sabóia-Morais Cesar Koppe Grisolia 《Bulletin of environmental contamination and toxicology》2013,91(5):583-587
Poecilia reticulata were exposed to herbicide Roundup Transorb® for micronucleus test, nuclear abnormalities and comet assay. The exposure-concentrations were based on CL50–96 h following 0, 1.41, 2.83, 4.24 and 5.65 μL L?1 for 24 h. Micronucleus and comets were significantly increased in the gill erythrocyte cells after herbicide exposure compared with the non-exposed group. Results showed a gradual increase in the number of damaged cells, indicating a concentration-dependent effect and that this herbicide was mutagenic and genotoxic to P. reticulata and this effect could be attributed to a combination of compounds contained in the formulation with the active ingredient glyphosate. 相似文献
122.
Tatiana L. Fonseca Mayrin Correa-Medina Maira P.O. Campos Gabor Wittmann Joao P. Werneck-de-Castro Rafael Arrojo e Drigo Magda Mora-Garzon Cintia Bagne Ueta Alejandro Caicedo Csaba Fekete Balazs Gereben Ronald M. Lechan Antonio C. Bianco 《The Journal of clinical investigation》2013,123(4):1492-1500
Type II deiodinase (D2) activates thyroid hormone by converting thyroxine (T4) to 3,5,3′-triiodothyronine (T3). This allows plasma T4 to signal a negative feedback loop that inhibits production of thyrotropin-releasing hormone (TRH) in the mediobasal hypothalamus (MBH) and thyroid-stimulating hormone (TSH) in the pituitary. To determine the relative contributions of these D2 pathways in the feedback loop, we developed 2 mouse strains with pituitary- and astrocyte-specific D2 knockdown (pit-D2 KO and astro-D2 KO mice, respectively). The pit-D2 KO mice had normal serum T3 and were systemically euthyroid, but exhibited an approximately 3-fold elevation in serum TSH levels and a 40% reduction in biological activity. This was the result of elevated serum T4 that increased D2-mediated T3 production in the MBH, thus decreasing Trh mRNA. That tanycytes, not astrocytes, are the cells within the MBH that mediate T4-to-T3 conversion was defined by studies using the astro-D2 KO mice. Despite near-complete loss of brain D2, tanycyte D2 was preserved in astro-D2 KO mice at levels that were sufficient to maintain both the T4-dependent negative feedback loop and thyroid economy. Taken together, these data demonstrated that the hypothalamic-thyroid axis is wired to maintain normal plasma T3 levels, which is achieved through coordination of T4-to-T3 conversion between thyrotrophs and tanycytes. 相似文献
123.
Flaviana R. Fernandes Weverson A. Ferreira Mariana A. Campos Guilherme S. Ramos Kelly C. Kato Gregório G. Almeida José D. Corrêa Junior Maria N. Melo Cynthia Demicheli Frédéric Frézard 《Antimicrobial agents and chemotherapy》2013,57(9):4229-4236
The need for daily parenteral administration is an important limitation in the clinical use of pentavalent antimonial drugs against leishmaniasis. In this study, amphiphilic antimony(V) complexes were prepared from alkylmethylglucamides (L8 and L10, with carbon chain lengths of 8 and 10, respectively), and their potential for the oral treatment of visceral leishmaniasis (VL) was evaluated. Complexes of Sb and ligand at 1:3 (SbL8 and SbL10) were obtained from the reaction of antimony(V) with L8 and L10, as evidenced by elemental and electrospray ionization-tandem mass spectrometry (ESI-MS) analyses. Fluorescence probing of hydrophobic environment and negative-staining transmission electron microscopy showed that SbL8 forms kinetically stabilized nanoassemblies in water. Pharmacokinetic studies with mice in which the compound was administered by the oral route at 200 mg of Sb/kg of body weight indicated that the SbL8 complex promoted greater and more sustained Sb levels in serum and liver than the levels obtained for the conventional antimonial drug meglumine antimoniate (Glucantime [Glu]). The efficacy of SbL8 and SbL10 administered by the oral route was evaluated in BALB/c mice infected with Leishmania infantum after a daily dose of 200 mg of Sb/kg for 20 days. Both complexes promoted significant reduction in the liver and spleen parasite burdens in relation to those in the saline-treated control group. The extent of parasite suppression (>99.96%) was similar to that achieved after Glu given intraperitoneally at 80 mg of Sb/kg/day. As expected, there was no significant reduction in the parasitic load in the group treated orally with Glu at 200 mg of Sb/(kg day). In conclusion, amphiphilic antimony(V) complexes emerge as an innovative and promising strategy for the oral treatment of VL. 相似文献
124.
125.
Pêgo-Fernandes PM de Campos JR Jatene FB Marchiori P Suso FV de Oliveira SA 《The Annals of thoracic surgery》2002,74(1):204-208
BACKGROUND: Myasthenia gravis is an autoimmune disease characterized by weakness and fatigue of voluntary muscles. Surgical treatment of choice for myasthenia gravis has been thymectomy. However, thymectomy indications and surgical approach are still controversial. The purpose of this study is to evaluate the efficacy of partial median sternotomy approach to the thymus. METHODS: From 1973 to 1999, 478 patients with myasthenia gravis underwent thymectomy through a partial median sternotomy. RESULTS: Sixty-one patients (12.7%) had complete remission of symptoms, 299 (62.5%) had a significant improvement, and 83 (17.4%), a mild improvement; whereas 35 patients (7.4%) had no improvement of clinical symptoms. CONCLUSIONS: Partial median sternotomy has shown to be a useful surgical approach to the thymus, as demonstrated by the good functional and aesthetic results, associated with low morbidity and no mortality. 相似文献
126.
Rodrigo C. Souza Juliana Campos Junqueira Rodnei D. Rossoni Cristiane A. Pereira Egberto Munin Antonio O. C. Jorge 《Lasers in medical science》2010,25(3):385-389
This study was to evaluate specific effects of photodynamic therapy (energy density 15.8 J/cm2, 26.3 J/cm2 and 39.5 J/cm2) using methylene blue, toluidine blue and malachite green as photosensitizers and low-power laser irradiation on the viability
of Candida albicans. Suspensions of C. albicans containing 106 cells/ml were standardized in a spectrophotometer. For each dye, 120 assays, divided into four groups according to the following
experimental conditions, were carried out: laser irradiation in the presence of the photosensitizer; laser irradiation only;
treatment with the photosensitizer only; no exposure to laser light or photosensitizer. Next, serial dilutions were prepared
and seeded onto Sabouraud dextrose agar for the determination of the number of colony-forming units per milliliter (CFU/ml).
The results were subjected to analysis of variance and the Tukey test (P < 0.05). Photodynamic therapy using the photosensitizers tested was effective in reducing the number of C. albicans.. The number of CFU/ml was reduced by between 0.54 log10 and 3.07 log10 and depended on the laser energy density used. Toluidine blue, methylene blue and malachite green were effective photosensitizers
in antimicrobial photodynamic therapy against C. albicans, as was low-power laser irradiation alone. 相似文献
127.
Vidal L Díaz F Villena A Moreno M Campos JG de Vargas IP 《Brain research bulletin》2006,70(4-6):406-413
We investigated the expression of nitric oxide synthase (NOS) isoforms -1, -2 and -3 in the retina and optic nerve head (ONH) in an experimental rat model of elevated intraocular pressure (IOP) before and after treatment with timolol, to assess whether its neuroprotective action is associated with the activity of these enzymes. Episcleral vein cauterization in unilateral eyes of Wistar rats was performed to produce elevated IOP. Histological sections of retina and ONH from animals with normal IOP, with elevated IOP, and elevated IOP treated with timolol, were studied by immunohistochemistry with antibodies to NOS-1, NOS-2, and NOS-3. In the control rats, NOS-1 was localized to photoreceptor inner segments, amacrine cells and bipolar cells in the retina, and in astrocytes, pericytes and vascular nitrergic terminals in the ONH. NOS-3 immunostaining localized to the endothelial cells. The rats with elevated IOP showed increased expression of NOS-1 in the plexiform layers of the retina and reactive astrocytes in the ONH. These cells also showed NOS-2 positivity. The rats treated with timolol showed reduced expression of NOS-1 in the retina and ONH. NOS-2 was only detected in a few groups of astrocytes in the ONH. NOS-3 was unchanged in both elevated IOP and timolol-treated groups. These results show that excessive levels of NO synthesized by the NOS-1 and -2 isoforms, considered neurotoxic, might contribute to the progressive lesions of retinal ganglion cell axons. Their reduction after treatment suggests a possible neuroprotective effect of timolol in neurons exposed to excessive amounts of NO. 相似文献
128.
Prognostic value of 1H-MRS in neonatal encephalopathy 总被引:1,自引:0,他引:1
The aim of this study was to determine the prognostic value of proton magnetic resonance spectroscopy in neonatal encephalopathy. Studies were carried out in 11 consecutive term newborns with encephalopathy probably caused by hypoxic-ischemic injury. The clinical evaluation included pregnancy data, labor conditions, encephalopathy grade, presence of seizures, and necessity of antiepileptic drug therapy. Polygraphic recordings were obtained in all cases. Interest areas evaluated by spectroscopy were the basal ganglia and thalami. Among the cases, N-acetylaspartate/creatine, choline/creatine, and lactate/creatine ratios were calculated and related to the clinical variables, polygraphic recordings, and 6-month neurodevelopmental outcome. Abnormal follow-up occurred in 5 of 11 patients (45.4%) and was clearly related to an Apgar score <5 at 5 minutes (P = 0.003), encephalopathy grade (P = 0.02), early neonatal seizures (P = 0.02), and antiepileptic therapy (P = 0.01). No relationship was observed between spectroscopy results and polygraphic recordings profile. The lowest mean N-acetylaspartate/creatine ratio was observed in four of five patients with an adverse outcome and, although not statistically significant, demonstrated a clear trend to unfavorable follow-up (t test = 0.06). The choline/creatine ratios could not be related to follow-up in our sample. The most consistently observed abnormality on the spectra was the presence of the lactate peak in four of five patients with unfavorable outcome, with a high relative risk to determine evolution in the sample, relative risk 7.0 (chi2 = 0.01, 95% confidence interval = 1.1-42.9). 相似文献
129.
Ferri Campos J Chirivella Garrido J Caballero Coulón MC Noé Sebastián E 《Neurología (Barcelona, Spain)》2006,21(6):318-322
Anoxic encephalopathy is the consequence of acute cerebral oxygen deprivation usually generated by cardiac arrest and/or respiratory failure. Recently an interesting case of one patient with cerebral anoxia after ultraviolet radiation session has been published. This paper shows the clinical evolution of this patient after inclusion in a multidisciplinary rehabilitation program, which included treatment of the psychopathological, neuropsychological and functional impairments that this pathology often generates. Over successive decades cerebral anoxia has come to be identified principally as one of the most significant causes of an isolated amnesia syndrome. Our patient presented at baseline intense difficulties in every verbal and visual memory processes associated with moderate impairments in sustained, selective and shifting attention as well as temporal disorientation. Compensation of memory deficit was the main rehabilitation strategy used in this case. This rehabilitation approach was possible thanks to the high degree of self-awareness of memory deficits shown by the patient and the selective impairment of memory with partial preservation of the rest of cognitive functions. This particular case gives us the opportunity to show the multidisciplinary approach of cognitive rehabilitation and the process of reintegration to social activities and to productive work even when deficits persist. 相似文献
130.
Cascales Campos P Ramírez P Gonzalez R Domingo J Martínez Frutos I Sánchez Bueno F Robles R Miras M Pons JA Parrilla P 《Transplantation proceedings》2011,43(3):683-686