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1.
Acta Physiol (Oxf) ; 240(3): e14111, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38314948

RESUMO

AIM: This study aimed to investigate the effects of caffeine on pathways associated with mitochondrial quality control and mitochondrial capacity during skeletal muscle regeneration, focusing on the role of Parkin, a key protein involved in mitophagy. METHODS: We used in vitro C2C12 myoblast during differentiation with and without caffeine in the medium, and we evaluated several markers of mitochondrial quality control pathways and myotube growth. In vivo experiments, we used C57BL/6J (WT) and Parkintm 1Shn lineage (Parkin-/- ) mice and injured tibial anterior muscle. The mice regenerated TA muscle for 3, 10, and 21 days with or without caffeine ingestion. TA muscle was used to analyze the protein content of several markers of mitochondrial quality pathways, muscle satellite cell differentiation, and protein synthesis. Furthermore, it analyzed mtDNA, mitochondrial respiration, and myofiber growth. RESULTS: C2C12 differentiation experiments showed that caffeine decreased Parkin content, potentially leading to increased DRP1 and PGC-1α content and altered mitochondrial population, thereby enhancing growth capacity. Using Parkin-/- mice, we found that caffeine intake during the regenerative process induces an increase in AMPKα phosphorylation and PGC-1α and TFAM content, changes that were partly Parkin-dependent. In addition, the absence of Parkin potentiates the ergogenic effect of caffeine by increasing mitochondrial capacity and myotube growth. Those effects are related to increased ATF4 content and activation of protein synthesis pathways, such as increased 4E-BP1 phosphorylation. CONCLUSION: These findings demonstrate that caffeine ingestion changes mitochondrial quality control during skeletal muscle regeneration, and Parkin is a central player in those mechanisms.


Assuntos
Cafeína , Músculo Esquelético , Camundongos , Animais , Cafeína/farmacologia , Músculo Esquelético/metabolismo , Camundongos Endogâmicos C57BL , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Regeneração
2.
Animal ; 16(9): 100613, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35964480

RESUMO

Holstein × Gyr and Holstein are the primary dairy breeds used in tropical systems, but when rearing under pasture, feed intake, behavior, and performance might differ between them. This study aimed to evaluate the voluntary intake, nutrient digestibility, performance, and ingestive behavior of Holstein and Holstein × Gyr (½ Holstein × ½ Gyr) heifers managed in a rotational system of Guinea grass (Panicum maximum Jacq. cv. Mombaça). The experiment was conducted during the summer season throughout four periods of 21 d. Two 8-heifers (four Holstein and four Holstein × Gyr) groups, averaging 258.6 ±â€¯24.79 kg and 157.1 ±â€¯24.99 kg BW, were used. Each group grazed a separate set of 16 paddocks, and all heifers received a concentrate supplement daily. Heifers were weighed at the beginning and end of the experiment. Fecal, forage and concentrate samples were evaluated for their DM, CP, crude fat, ash, NDF, and indigestible NDF. Feeding behavior was evaluated through 24 h of live observation for 48 h of each experimental period. Grazing, ruminating, resting, and intake of concentrate times were recorded, and rumination criteria, bout criteria, mealtime, meal frequency, and meal duration were calculated. There was no difference in total dry matter intake (DMI), but forage DMI of Holstein × Gyr was 11.70 % greater than the Holstein heifers. The Holstein × Gyr heifers had greater NDF intake and feed efficiency tended to show greater CP and NDF digestibilities, consequently, they had greater average daily gain (ADG). Holstein grazed less than Holstein × Gyr heifers in the afternoon. Ruminating time was 18.43 % lower for Holstein than Holstein × Gyr heifers, and rumination criteria (i.e. longest non-feeding interval within a rumination event) were greater for Holstein heifers. Holstein heifers presented more prolonged rumination bouts and resting time than Holstein × Gyr heifers. Holstein × Gyr can ingest and ruminate greater amounts of fibrous material, and Holstein heifers needed to spend more time ruminating the cud. Overall, even though the behavior was not markedly different between breeds, rearing young Holstein heifers in tropical pasture conditions is less suitable than Holstein-Gyr because of their lower ADG. Therefore, this management condition seems appropriate for Holstein × Gyr but inappropriate for Holstein dairy heifers.


Assuntos
Ração Animal , Poaceae , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Digestão , Comportamento Alimentar , Feminino , Melhoramento Vegetal , Estações do Ano
3.
J Inorg Biochem ; 213: 111258, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33045595

RESUMO

Cisplatin has demonstrated extraordinary anticancer activity against a variety of solid tumors. However, its clinical efficacy is contrasted by its toxicity profile. Having in mind the need to reduce the toxicity, promote a sustained release and enhance the body-circulation time of cisplatin, herein novel nanocarriers consisting of core-shell silica-coated iron oxide nanoparticles functionalized with dicarboxylic acid groups were prepared and characterized. Cisplatin was conjugated with the functionalized nanoparticles by surface tethering. Controlled release of cisplatin was observed without burst effect and in a sustained profile for up to 3 days. In vitro studies showed cytotoxic and antiproliferative effects of the cisplatin nanoconjugates against a human pancreatic cancer cell line. Importantly, when compared with free cisplatin, nanoconjugates exhibited lower cytotoxic effects regarding nonmalignant human duct pancreatic cells.


Assuntos
Antineoplásicos/administração & dosagem , Cisplatino/administração & dosagem , Portadores de Fármacos , Magnetismo , Nanopartículas de Magnetita/química , Nanopartículas/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
SAR QSAR Environ Res ; 30(6): 383-401, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31144535

RESUMO

Praziquantel (PZQ) is the first line drug for the treatment of human Schistosoma spp. worm infections. However, it suffers from low activity towards immature stages of the worm, and its prolonged use induces resistance/tolerance. During the last 40 years, 263 PZQ analogues have been synthesized and tested against Schistosoma spp. worms, but less than 10% of them showed significant activity. Here, we propose a rationalization of the chemical space of the PZQ derivatives by a ligand-based approach. First, we constructed an in-house database with all PZQ derivatives available in the literature. This analysis shows a high heterogeneity in the data. Fortunately, all studies include PZQ as a reference, permitting the classification of compounds into three classes according to their activities. Models involving ligand-based pharmacophore and logistic regression were performed. Five physicochemical parameters were identified as the best to explain the biological activity. In the end, we proposed new PZQ derivatives with modifications at positions 1 and 7, we analysed them with our models, and we observed that they can be more active than the previously synthesized derivatives. The main goal of this work was to conduct the most valuable meta-pharmacometrics/pharmacoinformatics analysis with all Praziquantel medicinal chemistry data available in the literature.


Assuntos
Praziquantel/análogos & derivados , Praziquantel/farmacologia , Schistosoma/efeitos dos fármacos , Esquistossomicidas/farmacologia , Animais , Química Farmacêutica , Humanos , Ligantes , Modelos Logísticos , Praziquantel/química , Relação Quantitativa Estrutura-Atividade , Esquistossomose/tratamento farmacológico , Esquistossomicidas/química
5.
Braz J Med Biol Res ; 51(6): e7180, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29694504

RESUMO

The aim of this study was to evaluate the effect of expiratory positive airway pressure (EPAP) on heart rate variability (HRV) indices at rest and during 6-min walk test (6MWT) in chronic obstructive pulmonary disease (COPD) patients. Fifteen moderate to severe COPD patients were randomized and evaluated with and without (Non-EPAP) a 5 cmH2O EPAP device. Respiratory rate (RR) was collected at rest (5 min), during the 6MWT (5 min), and at recovery (5 min). Indices of HRV were computed in the time domain, in the frequency domain, and nonlinear analysis. For EPAP and Non-EPAP during the 6MWT, we found an increased mean heart rate (HR) (P=0.001; P=0.001) while mean RR (P=0.001; P=0.015) and RR tri index decreased (P=0.006; P=0.028). Peripheral oxygen saturation (P=0.019) increased at rest only in the EPAP group. In EPAP, correlations were found between forced expiratory volume in 1 s (FEV1) and low frequency (LF) sympathetic tonus (P=0.05; r=-0.49), FEV1 and high frequency (HF) parasympathetic tonus at rest (P=0.05; r=0.49), lactate at rest and LF during the 6MWT (P=0.02; r=-0.57), and lactate at rest and HF during 6MWT (P=0.02; r=0.56). Through a linear regression model, we found that lactate at rest explained 27% of the alterations of LF during 6MWT. The use of 5 cmH2O EPAP improved autonomic cardiac modulation and its complexity at rest in COPD patients. Although it did not influence the performance of the 6MWT, the EPAP device caused alterations in resting lactate concentration with an effect on sympatho-vagal control during the test.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Volume Expiratório Forçado/fisiologia , Frequência Cardíaca/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Descanso/fisiologia , Teste de Caminhada/métodos , Estudos Cross-Over , Estudos Transversais , Humanos , Ácido Láctico/metabolismo , Masculino , Pessoa de Meia-Idade , Taxa Respiratória/fisiologia , Índice de Gravidade de Doença
7.
Scand J Med Sci Sports ; 26(11): 1360-1372, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27152850

RESUMO

Experimental studies have reported that aerobic exercise after asthma induction reduces lung inflammation and remodeling. Nevertheless, no experimental study has analyzed whether regular/moderate aerobic training before the induction of allergic asthma may prevent these inflammatory and remodeling processes. For this purpose, BALB/c mice (n = 96) were assigned into non-trained and trained groups. Trained animals ran on a motorized treadmill at moderate intensity, 30 min/day, 3 times/week, for 8 weeks, and were further randomized into subgroups to undergo ovalbumin sensitization and challenge or receive saline using the same protocol. Aerobic training continued until the last challenge. Twenty-four hours after challenge, compared to non-trained animals, trained mice exhibited: (a) increased systolic output and left ventricular mass on echocardiography; (b) improved lung mechanics; (c) decreased smooth muscle actin expression and collagen fiber content in airways and lung parenchyma; (d) decreased transforming growth factor (TGF)-ß levels in bronchoalveolar lavage fluid (BALF) and blood; (e) increased interferon (IFN)-γ in BALF and interleukin (IL)-10 in blood; and (f) decreased IL-4 and IL-13 in BALF. In conclusion, regular/moderate aerobic training prior to allergic asthma induction reduced inflammation and remodeling, perhaps through increased IL-10 and IFN-γ in tandem with decreased Th2 cytokines.


Assuntos
Remodelação das Vias Aéreas , Asma/imunologia , Citocinas/imunologia , Pulmão/imunologia , Condicionamento Físico Animal , Animais , Asma/induzido quimicamente , Líquido da Lavagem Broncoalveolar/imunologia , Imuno-Histoquímica , Inflamação , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-13/imunologia , Interleucina-4/imunologia , Pulmão/patologia , Pulmão/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Ovalbumina/efeitos adversos , Pneumonia/induzido quimicamente , Pneumonia/imunologia , Pneumonia/patologia , Fator de Crescimento Transformador beta/imunologia
8.
Toxicol Lett ; 249: 29-41, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27021274

RESUMO

Surface coating of silver nanoparticles may influence their toxicity, in a way yet to decipher. In this study, human keratinocytes (HaCaT cells) were exposed for 24 and 48h to well-characterized 30nm AgNPs coated either with citrate (Cit30 AgNPs) or with poly(ethylene glycol) (PEG30 AgNPs), and assessed for cell viability, reactive oxygen species (ROS), cytokine release, apoptosis and cell cycle dynamics. The results showed that Cit30 AgNPs and PEG30 AgNPs decreased cell proliferation and viability, the former being more cytotoxic. The coating molecules per se were not cytotoxic. Moreover, Ag(+) release and ROS production were similar for both AgNP types. Cit30 AgNPs clearly induced apoptotic death, while cells exposed to PEG30 AgNPs appeared to be at an earlier phase of apoptosis, supported by changes in BAX, BCL2 and CASP-3 expressions. Concerning the impact on cell cycle dynamics, both Cit30 and PEG30 AgNPs affected cell cycle regulation of HaCaT cells, but, again, citrate-coating induced more drastic effects, showing earlier downregulation of cyclin B1 gene and cellular arrest at the G2 phase. Overall, this study has shown that the surface coating of AgNPs influences their toxicity by differently regulating cell-cycle and cell death mechanisms.


Assuntos
Ácido Cítrico/farmacologia , Queratinócitos/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Polietilenoglicóis/farmacologia , Prata/toxicidade , Anexina A5/análise , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Citometria de Fluxo , Humanos , Espécies Reativas de Oxigênio/metabolismo
9.
Br J Pharmacol ; 173(7): 1236-47, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26989986

RESUMO

BACKGROUND AND PURPOSE: Asthma is characterized by chronic lung inflammation and airway hyperresponsiveness. Despite recent advances in understanding of its pathophysiology, asthma remains a major public health problem, and new therapeutic strategies are urgently needed. In this context, we sought to ascertain whether treatment with the TK inhibitor dasatinib might repair inflammatory and remodelling processes, thus improving lung function, in a murine model of asthma. EXPERIMENTAL APPROACH: Animals were sensitized and subsequently challenged, with ovalbumin (OVA) or saline. Twenty-four hours after the last challenge, animals were treated with dasatinib, dexamethasone, or saline, every 12 h for 7 consecutive days. Twenty-four hours after the last treatment, the animals were killed, and data were collected. Lung structure and remodelling were evaluated by morphometric analysis, immunohistochemistry, and transmission electron microscopy of lung sections. Inflammation was assessed by cytometric analysis and ELISA, and lung function was evaluated by invasive whole-body plethysmography. KEY RESULTS: In OVA mice, dasatinib, and dexamethasone led to significant reductions in airway hyperresponsiveness. Dasatinib was also able to attenuate alveolar collapse, contraction index, and collagen fibre deposition, as well as increasing elastic fibre content, in OVA mice. Concerning the inflammatory process, dasatinib reduced inflammatory cell influx to the airway and lung-draining mediastinal lymph nodes, without inducing the thymic atrophy promoted by dexamethasone. CONCLUSIONS AND IMPLICATIONS: In this model of allergic asthma, dasatinib effectively blunted the inflammatory and remodelling processes in asthmatic lungs, enhancing airway repair and thus improving lung mechanics.


Assuntos
Remodelação das Vias Aéreas/efeitos dos fármacos , Asma/tratamento farmacológico , Dasatinibe/farmacologia , Pulmão/efeitos dos fármacos , Proteínas Tirosina Quinases/antagonistas & inibidores , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Asma/imunologia , Asma/patologia , Asma/fisiopatologia , Dasatinibe/uso terapêutico , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Feminino , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/fisiopatologia , Pulmão/patologia , Pulmão/fisiopatologia , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia
10.
Analyst ; 140(5): 1693-701, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25630833

RESUMO

The controlled release of pesticides using hydrogel vehicles is an important procedure to limit the amount of these compounds in the environment, providing an effective way for crop protection. A key-step in the formulation of new materials for these purposes encompasses the monitoring of available pesticides in the gel matrix under variable working conditions. In this work, we report a series of bionanocomposites made of Ag nanoparticles (NPs) and gelatine A for the surface enhanced Raman scattering (SERS) detection of sodium diethyldithiocarbamate (EtDTC) as a pesticide model. These studies demonstrate the effectiveness of these substrates for the detection of EtDTC in aqueous solutions in a concentration as low as 10(-5) M. We have monitored the Raman signal enhancement of this analyte in bionanocomposites having an increasing amount of gelatine due to their relevance in formulating hydrogels of variable gel strengths. Under these conditions, the bionanocomposites have shown an effective SERS activity using EtDTC, demonstrating their effectiveness in the qualitative detection of this analyte. Finally, experiments involving the release of EtDTC from Ag/gelatine samples have been monitored by SERS, which attest the potential of this spectroscopic method in the laboratorial monitoring of hydrogels for pesticide release.


Assuntos
Ditiocarb/análise , Gelatina/química , Nanopartículas Metálicas/química , Nanocompostos/química , Praguicidas/análise , Prata/química , Análise Espectral Raman/métodos , Quelantes/análise , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Propriedades de Superfície
11.
Horm Metab Res ; 46(7): 505-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24446155

RESUMO

The objective of this prospective study was to compare the results of color flow Doppler sonography (CFDS) and radioiodine scintigraphy in patients with thyrotoxicosis. A total of 176 patients, 102 with clinical thyrotoxicosis and 74 with subclinical dysfunction, were included. Pregnant and breast-feeding women, patients using amiodarone or recently exposed to iodinated contrast, and patients treated with antithyroid drugs were excluded. Total T3, free T4, TSH, and anti-TSH receptor antibodies were measured before scintigraphy and CFDS. Excluding one patient whose etiology of thyrotoxicosis remained undefined, CFDS showed 100% specificity. In fact, in all 10 cases in which scintigraphy and CFDS provided discordant results, the diagnosis suggested by the latter was correct. In patients with clinical thyrotoxicosis, the sensitivity of CFDS was 96% for diffuse toxic goiter, 95% for the absence of hyperfunction, and 100% for toxic nodular disease. In patients with subclinical dysfunction, the sensitivity of CFDS was 72.7% for diffuse toxic goiter, 90% for toxic adenoma, and 86.6% for toxic multinodular disease. CFDS was inconclusive in patients with parenchymal blood flow with patchy uneven distribution or with macronodules in which nodule vascularity compared to the remaining parenchyma did not permit to establish the diagnosis with certainty. CFDS can be used instead of scintigraphy not only in situations in which the latter is contraindicated or of limited value to define the etiology of thyrotoxicosis.


Assuntos
Tireotoxicose/diagnóstico por imagem , Tireotoxicose/etiologia , Ultrassonografia Doppler em Cores , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Sensibilidade e Especificidade , Adulto Jovem
12.
J Appl Microbiol ; 115(5): 1222-30, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23910219

RESUMO

AIMS: The aim of the present work was to study the in vitro effect of native and recombinant Bauhinia variegata var. variegata lectins in inhibiting early adhesion of Streptococcus mutans, Streptococcus sanguis and Streptococcus sobrinus to experimentally acquired pellicle. METHODS AND RESULTS: Native lectin from B. variegata (BVL) was purified by affinity chromatography of extract of seeds. The recombinant lectin (rBVL-I) was expressed in E. coli strain BL21 (DE3) from a genomic clone encoding the mature B. variegata lectin gene using the vector pAE-bvlI. Recombinant protein deposited in inclusion bodies was solubilized and subsequently purified by affinity chromatography. The rBVL-I was compared to BVL for agglutination of erythrocytes and initial adherence of oral bacteria on a saliva-coated surface. The results revealed that rBVL-I acts similarly to BVL for agglutination of erythrocytes. Both lectins showed adhesion inhibition effect on Step. sanguis, Step. mutans and Step. sobrinus. CONCLUSION: We report, for the first time, the inhibition of early adhesion of oral bacteria by a recombinant lectin. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results support the proposed biotechnological application of lectins in a strategy to reduce development of dental caries by inhibiting the initial adhesion and biofilm formation.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Bauhinia/química , Escherichia coli/metabolismo , Lectinas/farmacologia , Streptococcus/efeitos dos fármacos , Animais , Biofilmes/efeitos dos fármacos , Cromatografia de Afinidade , Testes de Hemaglutinação , Humanos , Lectinas/isolamento & purificação , Extratos Vegetais/química , Coelhos , Proteínas Recombinantes/farmacologia , Saliva/química , Sementes/química , Streptococcus/fisiologia
13.
Environ Sci Pollut Res Int ; 20(9): 5963-74, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23508538

RESUMO

The sorption capacity of nanoporous titanosilicate Engelhard titanosilicate number 4 (ETS-4) and silica-coated magnetite particles derivatised with dithiocarbamate groups towards Hg(II) was evaluated and compared in spiked ultra-pure and spiked surface-river water, for different batch factors. In the former, and using a batch factor of 100 m(3)/kg and an initial Hg(II) concentrations matching the maximum allowed concentration in an effluent discharge, both materials achieve Hg(II) uptake efficiencies in excess of 99 % and a residual metal concentration lower than the guideline value for drinking water quality. For the surface-river water and the same initial concentration, the Hg(II) uptake efficiency of magnetite particles is outstanding, achieving the quality criteria established by the Water Framework Directive (concerning Hg concentration in surface waters) using a batch factor of 50 m(3)/kg, while the efficiency of ETS-4 is significantly inferior. The dissimilar sorbents' Hg(II) removal efficiency is attributed to different uptake mechanisms. This study also highlights the importance of assessing the effective capacity of the sorbents under realistic conditions in order to achieve trustable results.


Assuntos
Óxido Ferroso-Férrico/química , Nanopartículas de Magnetita/química , Mercúrio/química , Tiocarbamatos/química , Poluentes Químicos da Água/química , Água/química , Monitoramento Ambiental , Cinética , Rios/química , Purificação da Água
14.
J Gynecol Obstet Biol Reprod (Paris) ; 41(6): 512-8, 2012 Oct.
Artigo em Francês | MEDLINE | ID: mdl-22633037

RESUMO

The recent emergence of oncofertility raises the question of ovarian stimulation and its risks when performed for oocyte or/and embryo cryopreservation in a fertility preservation program. The relation between ovarian stimulation and cancer has been marked by the possible direct or indirect tumorigenic role for pituitary gonadotrophins in the tumorogenesis. Although the growth of many gonadal and extragonadal tumors is stimulated by gonadal sex hormones, whose production is regulated by gonadotrophins, there is still a lack of data to consider FSH and LH as tumor promoters. The purpose of this brief review is to present on one hand, the questions raised by the administration of exogenous gonadotrophins in cancer patients and on the other, to evaluate both experimental and clinical data about the possible relation between gonadotrophins and tumorogenesis.


Assuntos
Preservação da Fertilidade , Gonadotropinas/uso terapêutico , Neoplasias/terapia , Adenocarcinoma/terapia , Neoplasias da Mama/terapia , Criopreservação/estatística & dados numéricos , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Preservação da Fertilidade/métodos , Preservação da Fertilidade/estatística & dados numéricos , Humanos , Neoplasias/reabilitação , Oócitos , Neoplasias Ovarianas/terapia , Indução da Ovulação/métodos , Indução da Ovulação/estatística & dados numéricos , Gravidez
15.
Hum Reprod ; 27(4): 1066-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22279090

RESUMO

BACKGROUND: Looking for a qualitative marker of ovarian function, we aimed to verify whether responsiveness of antral follicles to FSH administration, as reflected by the Follicular Output RaTe (FORT), is related to their reproductive competence. METHODS: We studied 322 IVF-ET candidates aged 25-43 years who underwent controlled ovarian hyperstimulation with similar initial FSH doses. Antral follicle (3-8 mm) count (AFC) and pre-ovulatory follicle (16-22 mm) count (PFC) were performed, respectively, at the achievement of pituitary suppression (before FSH treatment) and on the day of hCG administration. The FORT was calculated by PFC × 100/AFC. FORT groups were set according to tercile values: low (<42%; n= 102), average (42-58%; n= 123) and high (>58%; n= 97). RESULTS: The average FORT was 50.6% (range, 16.7-100.0%). Clinical pregnancy rates per oocyte retrieval increased progressively from the low to the high FORT groups (33.3, 51.2 and 55.7%, respectively, P< 0.003) and such a relationship assessed by logistic regression was independent of the confounding covariates, women's ages, AFC and PFC. CONCLUSIONS: The observed relationship between IVF-ET outcome and the percentage of antral follicles that effectively respond to FSH administration reaching pre-ovulatory maturation suggests that FORT may be a qualitative reflector of ovarian follicular competence. Further studies with broader inclusion criteria and more personalized protocols are needed to validate these results.


Assuntos
Transferência Embrionária , Fertilização in vitro , Hormônio Foliculoestimulante/farmacologia , Folículo Ovariano/efeitos dos fármacos , Adulto , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Modelos Logísticos , Indução da Ovulação , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Prospectivos , Resultado do Tratamento
16.
Water Res ; 45(17): 5773-84, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21924455

RESUMO

In order to take advantage of the high affinity between mercury and sulphur, magnetite (Fe(3)O(4)) particles functionalized with dithiocarbamate groups (CS(2)(-)), were synthesized to be used as a new type of sorbent to remove Hg (II) from synthetic and natural spiked waters. The effectiveness of this type of sorbent was studied, and its potential as cleanup agent for contaminated waters was assessed. Batch stirred tank experiments were carried out by contacting a volume of solution with known amounts of functionalized Fe(3)O(4) particles, in order to study the effect of sorbent dose, salinity, and the kinetics and the equilibrium of this unit operation. A complete Hg (II) removal (ca. 99.8%) was attained with 6 mg/L of magnetic particles for an initial metal concentration of 50 µg/L. It was confirmed that highly complex matrices, such as seawater (ca. 99%) and river water (ca. 97%), do not affect the removal capacity of the functionalized magnetic particles. Concerning isotherms, no significant differences were observed between two- and three-parameter models (P = 0.05%); however, Sips isotherm provided the lowest values of SS and S(x/y), predicting a maximum sorption capacity of 206 mg/g, in the range of experimental conditions under study. The solid loadings measured in this essay surmount the majority of the values found in literature for other type of sorbents.


Assuntos
Ditiocarb/química , Óxido Ferroso-Férrico/química , Mercúrio/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Água/química , Adsorção , Cinética , Salinidade , Dióxido de Silício/química , Espectrofotometria Infravermelho , Propriedades de Superfície , Temperatura , Fatores de Tempo , Difração de Raios X
17.
Gynecol Obstet Fertil ; 38(7-8): 471-4, 2010.
Artigo em Francês | MEDLINE | ID: mdl-20594897

RESUMO

All indicates that anti-Müllerian hormone (AMH), though initially studied for its importance on male development, plays an inhibiting role on the initial and cyclic processes of follicular recruitment. The aspects involved in its regulation are still poorly understood, but the oocyte, some steroids, and follicular development itself seem to be involved. In addition, AMH has become an important clinical marker of ovarian functioning for many reasons, including its exclusive production by granulosa follicles at many stages of development, its probable FSH independence, its low inter and intracycle variability and its reliable quantitative (qualitative?) relationship with ovarian follicles and their response to exogenous FSH. The growing interest in ovarian AMH incited us to review some important fundamental and clinical publications in this field.


Assuntos
Hormônio Antimülleriano/fisiologia , Biomarcadores , Folículo Ovariano/fisiologia , Animais , Hormônio Antimülleriano/genética , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Oócitos/fisiologia , Ovário/fisiologia , Indução da Ovulação
19.
Acta Biomater ; 6(9): 3611-20, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20350622

RESUMO

Thermally induced phase separation (TIPS) has proven to be a suitable method for the preparation of porous structures for tissue engineering applications, and particular attention has been paid to increasing the pore size without the use of possible toxic surfactants. Within this context, an alternative method to control the porosity of polymeric scaffolds via the combination with a bioglass is proposed in this work. The addition of a bioactive glass from the 3CaO x P2O5-MgO-SiO2 system enables the porous structure of high molecular weight poly(l-lactic) acid (PLLA) scaffolds prepared by TIPS to be tailored. Bioglass acts as a nucleating catalyst agent of the PLLA matrix, promoting its crystallization, and the glass solubility controls the pore size. A significant increase in the pore size is observed as the bioglass content increases and scaffolds with large pore size (approximately 150 microm) can be prepared. In addition, the bioactive character of the scaffolds is proved by in vitro tests in synthetic plasma. The importance of this approach resides on the combination of the ability to tailor the porosity of polymeric scaffolds via the tunable solubility of bioglasses, without the use of toxic surfactants, leading to a composite structure with suitable properties for bone tissue engineering applications.


Assuntos
Cerâmica/química , Ácido Láctico/química , Polímeros/química , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Varredura Diferencial de Calorimetria , Força Compressiva , Cristalização , Módulo de Elasticidade , Íons/análise , Microscopia Eletrônica de Varredura , Peso Molecular , Tamanho da Partícula , Poliésteres , Porosidade , Espalhamento de Radiação , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo
20.
Phytomedicine ; 17(8-9): 679-83, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19962290

RESUMO

Aromatherapy uses essential oils (EOs) for several medical purposes, including relaxation. The association between the use of aromas and a decrease in anxiety could be a valuable instrument in managing anxiety in an ever increasing anxiogenic daily life style. Linalool is a monoterpene commonly found as the major volatile component of EOs in several aromatic plant species. Adding to previously reported sedative effects of inhaled linalool, the aim of this study was to investigate the effects of inhaled linalool on anxiety, aggressiveness and social interaction in mice. Additionally, we investigated the effects of inhaled linalool on the acquisition phase of a step-down memory task in mice. Inhaled linalool showed anxiolytic properties in the light/dark test, increased social interaction and decreased aggressive behavior; impaired memory was only seen the higher dose of linalool. These results strengthen the suggestion that inhaling linalool rich essential oils can be useful as a mean to attain relaxation and counteract anxiety.


Assuntos
Agressão/efeitos dos fármacos , Ansiolíticos/uso terapêutico , Aromaterapia , Comportamento Animal/efeitos dos fármacos , Monoterpenos/uso terapêutico , Óleos Voláteis/uso terapêutico , Extratos Vegetais/uso terapêutico , Monoterpenos Acíclicos , Administração por Inalação , Animais , Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Escuridão , Luz , Masculino , Memória/efeitos dos fármacos , Camundongos , Monoterpenos/efeitos adversos , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia
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