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31.
Lara Clemes Assis Mariana Appel Hort Gisele Volpato de Souza Alessandra Cadete Martini Stefânia Forner Daniel Fernandes Martins Jenniffer Carolina Silva Heros Horst Adair Roberto Soares dos Santos Moacir Geraldo Pizzolatti Giles Alexander Rae Janice Koepp Andreza Fabro de Bem Rosa Maria Ribeiro do Valle 《The Journal of pharmacy and pharmacology》2014,66(5):694-704
32.
Mariana Abreu Costa Valéria Fonseca Moscardini Pablo da Costa Gontijo Geraldo Andrade Carvalho Rodrigo Lopes de Oliveira Harley Nonato de Oliveira 《Ecotoxicology (London, England)》2014,23(8):1399-1408
This study assessed the transgenerational effects of insecticides in developing Trichogramma galloi (Hymenoptera: Trichogrammatidae). Laboratory bioassays were performed in which five insecticides were sprayed on egg-larval, pre-pupal and pupal stages of the parasitoid. The interaction between insecticides and development stages of the parasitoid was not significant for the rate of F0 emergence. All insecticides significantly reduced the emergence of wasps, with the lowest emergence observed when they were applied to the pupal stage. For the sex ratio, only spinosad applied to the pre-pupal stage and triflumuron applied on the egg-larval and pre-pupal stages did not differ from the controls. Triflumuron applied to pre-pupae did not lead to any difference in the parasitism rate of the treated generation (F0) when compared to the control. There were no significant differences among survival curves for females of F0 when all insecticides were sprayed on the egg-larval stage. Both concentrations of lambda-cyhalothrin + thiamethoxam reduced female pre-pupal survival, and all treatments reduced female pupal survival. In addition, we observed a transgenerational effect of the insecticides on emergence and sex ratio of next generation (F1). Lambda-cyhalothrin + thiamethoxam (Min) applied to the pre-pupae and pupae, the maximum rate of the same insecticides applied to the egg-larvae and pre-pupae, and spinosad applied to pre-pupae all significantly reduced the adults emergence of T. galloi F1 generation. Only triflumuron did not alter the F1 sex ratio. These bioassays provide a basis for better understanding the effects of insecticide use on beneficial parasitoids. 相似文献
33.
Erick Miranda Souza Amanda Martins Calixto Camila Nara e Lima Fernanda Geraldo Pappen Gustavo De-Deus 《Journal of endodontics》2014
Introduction
Stabilizing sodium hypochlorite (NaOCl) at an alkaline pH is proposed to increase solution stability and tissue dissolution ability; however, a reduction on the flexural strength of dentin discs has been found to be a side effect. This study sought to determine whether a stabilized alkaline NaOCl reduces the fracture resistance of root canal–treated bovine teeth after root canal preparation compared with a neutral solution counterpart.Methods
The 4 anterior incisors were removed from 20 mandibular bovine jaws, and each 1 was randomly assigned to 1 of 4 groups (20 teeth each). Teeth were prepared with a sequence of 6 K-type files. The following experimental groups received a different irrigation regimen: G1: distilled water (negative control), G2: 5% NaOCl at a pH of 7.2, and G3: 5% NaOCl at a pH of 12.8; in the positive control group (G4), teeth remained untreated. The time of contact and volume of solution were carefully standardized. After bone and periodontal ligament simulation, teeth were subjected to a fracture resistance test.Results
A significant difference was observed among the 4 groups tested (analysis of variance, P < .05). The 5% NaOCl groups (G2 and G3) presented significantly lower resistance to fracture than the control (G1 and G4) (Tukey test, P < .05). Both NaOCl solutions similarly reduced the fracture resistance at approximately 30% (Tukey test, P > .05). No differences were observed between positive and negative control groups (Tukey test, P > .05).Conclusions
Stabilized alkaline and neutral NaOCl solutions similarly reduced the fracture resistance of root canal–treated bovine teeth by about 30%. 相似文献34.
Ayala Tovy Carina Rosas Amos S. Gaikwad Geraldo Medrano Linda Zhang Jaime M. Reyes Yung-Hsin Huang Tatsuhiko Arakawa Kristen Kurtz Shannon E. Conneely Anna G. Guzman Rogelio Aguilar Anne Gao Chun-Wei Chen Jean J. Kim Melissa T. Carter Amaia Lasa-Aranzasti Irene Valenzuela Lionel Van Maldergem Lorenzo Brunetti M. John Hicks Andrea N. Marcogliese Margaret A. Goodell Rachel E. Rau 《Haematologica》2022,107(4):887
Tatton-Brown-Rahman syndrome (TBRS) is an overgrowth disorder caused by germline heterozygous mutations in the DNA methyltransferase DNMT3A. DNMT3A is a critical regulator of hematopoietic stem cell (HSC) differentiation and somatic DNMT3A mutations are frequent in hematologic malignancies and clonal hematopoiesis. Yet, the impact of constitutive DNMT3A mutation on hematopoiesis in TBRS is undefined. In order to establish how constitutive mutation of DNMT3A impacts blood development in TBRS we gathered clinical data and analyzed blood parameters in 18 individuals with TBRS. We also determined the distribution of major peripheral blood cell lineages by flow cytometric analyses. Our analyses revealed non-anemic macrocytosis, a relative decrease in lymphocytes and increase in neutrophils in TBRS individuals compared to unaffected controls. We were able to recapitulate these hematologic phenotypes in multiple murine models of TBRS and identified rare hematological and non-hematological malignancies associated with constitutive Dnmt3a mutation. We further show that loss of DNMT3A in TBRS is associated with an altered DNA methylation landscape in hematopoietic cells affecting regions critical to stem cell function and tumorigenesis. Overall, our data identify key hematopoietic effects driven by DNMT3A mutation with clinical implications for individuals with TBRS and DNMT3A-associated clonal hematopoiesis or malignancies. 相似文献
35.
Lymphatic vessel density and epithelial D2-40 immunoreactivity in pre-invasive and invasive lesions of the uterine cervix 总被引:3,自引:0,他引:3
Longatto-Filho A Pinheiro C Pereira SM Etlinger D Moreira MA Jubé LF Queiroz GS Baltazar F Schmitt FC 《Gynecologic oncology》2007,107(1):45-51
OBJECTIVE: We sought to determine the significance of lymphatic vessel density (LVD) in pre-malignant lesions and carcinomas of the uterine cervix and to evaluate the prognostic value of lymphatic invasion and D2-40 positivity in tumor cells in the three histological types of invasive lesions. The correlation of LVD, lymphatic invasion and D2-40 positivity in tumor cells with EGFR and COX-2 expressions was also evaluated. METHODS: We studied 50 cervicitis, 50 low-grade squamous intraepithelial lesions (LSIL) (CIN1), 51 high-grade squamous intraepithelial lesions (HSIL) (CIN2/CIN3), 49 invasive squamous cells carcinomas (SCC), 43 adenocarcinomas (AC) and 30 adenosquamous cells carcinomas (ASC). The immunoreaction assay was performed using the monoclonal antibody D2-40. RESULTS: Significant differences in LVD were found among all categories of pre-invasive and invasive lesions (p=0.001 and p<0.001, respectively). LVD in invasive lesions was significantly greater than in pre-invasive lesions (p<0.001) and no significant association was found between LVD in invasive lesions and both lymph node invasion and/or metastasis. D2-40 positivity in tumor cells was associated with a better prognosis in ASC cases. EGFR and COX-2 expressions in invasive lesions were not associated with LVD; however, they correlated with both lymphatic invasion and D2-40 positivity in tumor cells. CONCLUSIONS: Lymphatic neovascularization begins early in intraepithelial lesions and continues to increase towards malignancy. Both lymphatic invasion and decrease in D2-40 expression in tumor cells appear to have a prognostic value. 相似文献
36.
Riëm El Tahry Susana Ferrao Santos Pascal Vrielynck Marianne de Tourtchaninoff Thierry Duprez Geraldo Ribeiro Vaz Christian Raftopoulos Joon Yul Choi Zhong Irene Wang 《Epileptic Disord》2020,22(2):156-164
Aims: Magnetic resonance imaging is of paramount importance in the presurgical evaluation of drug resistant epilepsy. Detection of a potentially epileptogenic lesion significantly improves seizure outcome after surgery. To optimize the detection of subtle lesions, MRI post‐processing techniques may be of essential help. Methods: In this study, we aimed to evaluate the detection rate of the voxel‐based morphometric analysis program (MAP) in a prospective trial. We aimed to study the MAP+ findings in terms of their clinical value in the decision‐making process of the presurgical evaluation. Results: We included, prospectively, 21 patients who had negative MRI by visual analysis. In a first step, results of the conventional non‐invasive presurgical evaluation were discussed, blinded to the MAP results, in multidisciplinary patient management conferences to determine the possible seizure onset zone and to set surgical or invasive evaluation plans. Thereafter, MAP results were presented, and the change of initial clinical plan was recorded. All MAP detections were reaffirmed by a neuroradiologist with epilepsy expertise. For the 21 patients included, mean age at the time of patient management conference was 26 years (SD 15 +/‐ years, range: 5–54 years). In total, 4/21 had temporal lobe epilepsy and 17/21 had extra‐temporal lobe epilepsy. MAP was positive in 10/21 (47%) patients and in 6/10 (60%) a diagnosis of focal cortical dysplasia was confirmed after neuroradiologist review, corresponding to a 28% detection rate. MAP+ findings had a clear impact on the initial management in 7/10 patients (7/21, 33% of all patients), which included an adaptation of the intracranial EEG plan (6/7 patients), or the decision to proceed directly to surgery (1/7 patients). Conclusion: MRI post‐processing using the MAP method yielded an increased detection rate of 28% for subtle dysplastic lesions in a prospective cohort of MRI‐negative patients, indicating its potential value in epilepsy presurgical evaluation. 相似文献
37.
Meyer Knobel Helio Bisi Clovis de Araujo Peres Geraldo Medeiros-Neto 《Endocrine pathology》1993,4(4):205-214
Samples from 2 different locations within the same euthyroid multinodular goiters (SMG) and normal (N) human thyroids were assayed for their content of DNA, thyroglobulin (Tg), and stable iodine (1271), and determined the response of adenosine 3’,5’-cyclic monophosphate (cAMP) to TSH and NaF. Quantitative morphological estimation of histological components in the thyroid was performed and correlated with functional parameters. Regardless the zonal evaluation, in SMG the mean (± SD) DNA content (?g/mg tissue) (1.04 ± 0.86) was not statistically different from that in N (1.13 ± 0.21). The mean127I concentration (?g/?g DNA) in N tissues (0.357 ± 0.091) was greater than that in SMG (0.176 ± 0.074). In these tissues, the Tg mean level (± SD) (?g/?g DNA) was lower (28.3 ± 21.5) than that in N (75.6 ± 41.1). The mean relative proportion (Vv) of epithelial cells in SMG (range, 6.0–30.6%) was statistically different (p <0.00) from that observed in N tissues (range, 10.4–18.2%). The meanbasal (± SD) cAMP level (pmol/?g DNA) in these tissues (0.11 1 ± 0.036) was different (p < 0.05) from that in SMG (0.231 ± 0.026). In response to TSH (10 mU), both SMG and N increased their cAMP contents to 0.454 ± 0.045 and 0.572 ± 0.020, respectively. A further elevation in cAMP levels was observed in N (1.154 ± 0.210) after 75 mU TSH, whereas in SMG tissues, no consistent increase (0.609 ± 0.496) occurred. Goiter and normal thyroid slices were unable to increase their cAMP concentrations in response to NaF in vitro. No correlation was found between functional and morphological data in SMG samples. In contrast, this relation was quite uniform in normal thyroids. The results are concordant with the intrathyroidal pathogenic processes often cited for the heterogeneity in human goiter. 相似文献
38.
Fabiana Cardoso Vilela Marina de Mesquita Padilha Lucas dos Santos-e-Silva Geraldo Alves-da-Silva Alexandre Giusti-Paiva 《Journal of ethnopharmacology》2009
Ethnopharmacological relevance
Sonchus oleraceus L. has been used to relieve pain in Brazilian folk medicine.Aim of the study
Sonchus oleraceus L. has been used to relieve pain in Brazilian folk medicine. This study was conducted to establish the antinociceptive properties of hydroethanolic and dichloromethane extracts from aerial parts of Sonchus oleraceus in mice using chemical and thermal models of nociception.Materials and methods
The formalin, hot plate, and tail immersion tests as well as acetic acid-induced writhing were used to investigate the antinociceptive activity in mice.Results
Given orally, the extracts at test doses of 30–300 mg/kg, produced significant inhibitions on chemical nociception induced by intraperitoneal acetic acid and subplantar formalin since decreased the number of writhing episodes and the time licking. Treatment with the extracts in the same doses produced a significant increase of the reaction time in tail immersion and in the hot plate test. The extracts administered at 300 mg/kg, p.o. had a stronger antinociceptive effect than indomethacin (5 mg/kg, p.o.) and morphine (10 mg/kg, p.o.).Conclusion
The extracts of Sonchus oleraceus markedly demonstrated antinociceptive action in mice, which supports previous claims of its traditional use. 相似文献39.
Noguti AS Jarmy-Di Bella ZI de Oliveira E Castro RA Lima GR Baracat EC Sartori MG Girão MJ 《European journal of obstetrics, gynecology, and reproductive biology》2008,141(2):183-185
Objective
We aimed to study the cross-sectional area of levator ani muscle and the doppler velocimetric parameters of vessels its in premenopausal and postmenopausal women.Study design
Sixty-four patients, divided into 3 groups, were assessed: group I (20 women—average age 28 years) premenopausal and nulliparous (control); group II (24 women—average age 38 years, vaginal delivery 1–4) premenopausal with vaginal deliveries; group III (20 women—average age 55 years, parity 0–4) postmenopausal without hormonal therapy. Doppler velocimetry of levator ani muscle vessels through resistance and pulsatility indices was used and the means of the groups compared by adjusting the weighed variance model with multiple comparisons, according to Tukey's method. Similarly, we measured the cross-sectional area of the muscle using ultrasonography.Results
There was a significant increase in resistance and pulsatility indices in postmenopausal patients as compared to the other two groups. We also observed a significant decrease in the cross-sectional area of the muscle of postmenopausal patients when compared to those in premenopausal.Conclusion
The obtained results allow us to conclude that levator ani muscle vascularization significantly decreases after menopause (age and/or hipoestrogenism) and that it can be assumed that vaginal delivery does not promote long-term alterations in levator ani muscle vascularization. We also observed a significant decrease in the cross-sectional area of the muscle in postmenopausal women when compared to those in premenopausal. 相似文献40.