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1.
Opt Express ; 30(23): 41459-41472, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366624

RESUMO

With the increasing data rate requirements on short-reach links, the recent standardization of unamplified coherent optical systems is paving the way for a cost and power-effective solution, targeting a massive deployment in the near future. However, unamplified systems are introducing new challenges. Particularly, the performance is highly dependent on the peak-to-average power ratio (PAPR) of the transmitted signal, which puts at question the use of the typical constellation formats. In this work, we use an end-to-end deep learning framework to optimize the geometry of different constellation sizes, ranging from 8- to 128-ary constellations. In general, it is shown that the performance of these systems is maximized with constellations whose outer symbols are disposed in a square shape, owing to the minimization of the real-valued PAPR. Following this premise, we experimentally demonstrate that odd-bit constellations can be significantly optimized for unamplified coherent links, achieving power budget gains in the range of 0.5-3 dB through the geometric optimization of 8-, 32- and 128-ary constellations.

2.
Int Endod J ; 53(9): 1264-1274, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32535966

RESUMO

AIM: To assess the effects of octenidine dihydrochloride (OCT) on eukaryotic cells and the cytotoxicity of OCT associated with sodium hypochlorite - NaOCl (NaOCl/OCT). METHODOLOGY: L929 fibroblasts and human osteoblast-like cells (Saos-2) were exposed to 0.1% OCT, 2% CHX, 2.5% NaOCl, 5.25% NaOCl and mixtures of 5.25% NaOCl and 0.1% OCT (NaOCl/OCT) at 90 : 10, 80 : 20 and 50 : 50 ratios. Cell viability was assessed by methyl-thiazol-tetrazolium (MTT) and neutral red (NR) assays; type of cell death, by flow cytometry; cytoskeleton, by actin and α-tubulin fluorescence; and alkaline phosphatase (ALP) activity, by thymolphthalein release. The data were analysed by two-way ANOVA and Bonferroni tests (α = 0.05). RESULTS: MTT and NR assays revealed that 0.1% OCT had the lowest cytotoxicity (P < 0.05), followed by 2% CHX (P < 0.05). The 2.5% NaOCl, NaOCl/OCT 80 : 20 and NaOCl/OCT 50 : 50 solutions had intermediate cytotoxicity. NaOCl 5.25% and NaOCl/OCT 90 : 10 had the highest cytotoxicity (P < 0.05). The OCT group had a higher percentage of viable cells than the NaOCl and CHX groups (P < 0.05), and induced apoptosis at higher doses. The cytoskeleton alterations were observed at 0.12%, 0.6% and 2.02% for the NaOCl, CHX and OCT groups, respectively. The solutions did not induce ALP activity. CONCLUSION: Octenidine dihydrochloride was less cytotoxic, induced apoptosis at higher doses, caused few changes in the cytoskeleton and did not induce alkaline phosphatase activity. In addition, octenidine dihydrochloride reduced the cytotoxicity of 5.25% NaOCl when combined at 20 and 50%.


Assuntos
Irrigantes do Canal Radicular , Hipoclorito de Sódio , Clorexidina , Células Eucarióticas , Humanos , Iminas , Piridinas
3.
Arq. bras. med. vet. zootec. (Online) ; 69(5): 1089-1096, set.-out. 2017. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-876985

RESUMO

Informações sobre a vascularização da parede folicular e do corpo lúteo equino, associadas à superovulação, são escassas. Com o objetivo de avaliar o efeito superovulatório do extrato de pituitária equina (EPE) no fluxo sanguíneo folicular e luteal, foram utilizadas seis éguas Puro Sangue Árabe, em dois ciclos estrais (controle e tratamento). As éguas foram monitoradas diariamente por ultrassonografia modo B, até que os folículos atingissem diâmetro de 23mm (desvio). No ciclo tratamento, as éguas receberam 8mg de EPE, uma vez ao dia, por via IM, até que dois ou mais folículos atingissem o diâmetro entre 32 e 35mm. A ovulação foi induzida com acetato de deslorelina, quando os folículos atingiram, no mínimo, 35mm. No momento do desvio folicular, da indução da ovulação e do último exame pré-ovulatório, foi utilizada a ultrassonografia modo B para medir o diâmetro dos folículos e, no oitavo dia pós-ovulação, para a área do corpo lúteo (CL). Utilizou-se também ultrassonografia com Doppler colorido para avaliar a perfusão sanguínea da parede folicular e do parênquima luteal. No ciclo controle, foi realizado o mesmo procedimento, exceto pelo uso do EPE. Os dados foram submetidos à análise de variância, com nível de significância de 5%. Não foi observado efeito do EPE sobre o número de ovulações, o diâmetro dos folículos, a vascularização da parede folicular e a concentração sérica de estrógeno. Os animais, tratados ou não, apresentaram CLs funcionais, não havendo diferença na área do parênquima ou da vascularização luteal, nem na concentração sérica de progesterona, no oitavo dia após a ovulação. Foi observado que o EPE proporcionou um maior número de folículos subordinados no momento da indução da ovulação do folículo dominante (P ≤ 0,05). Embora esses folículos não tenham chegado a ovular, concluiu-se que o EPE atuou no crescimento de folículos, que podem ser utilizados em outras biotécnicas, como a transferência de oócitos, com maior aproveitamento da reserva folicular de ovários equinos.(AU)


Knowledge about follicle and corpus luteum vascularization associated with superovulation in mares is scarce. Aiming to evaluate the effect of equine pituitary extract (EPE) on superovulation, the experiment was conducted using six mares Purebred Arabian in two estrous cycles (control and treatment). The mares were synchronized, and monitored daily by ultrasound B mode until the follicles reached diameter ≤ 23 mm (deviation). In the treatment cycle, from the deviation, mares received 8 mg of EPE, once a day, intramuscularly, until two or more follicles reached a diameter between 32 and 35 mm. Ovulation was induced with deslorelin acetate when follicles reached at least 35 mm. At the time of follicular deviation, induction of ovulation and final preovulatory exam, it was used B-mode ultrasound to measure the diameter of follicles and on the eighth day after ovulation to measure the area of the corpus luteum (CL); color Doppler was also used to assess blood perfusion of the follicle wall and luteal parenchyma. In the control cycle was performed the same procedure except for the use of EPE. Data were subjected to analysis of variance, with 5% significance level. There was no effect of EPE on ovulation number, diameter of follicles, vascularity of the follicular wall and serum estrogen concentration. The animals treated or not, showed functional CLs, with no difference in parenchymal area or luteal vascularization, or in serum progesterone concentration on the eighth day after ovulation. It was observed that the EPE provided a greater number of subordinate follicles at the time of induction of ovulation of the dominant follicle. Although these follicles have failed to ovulate, it was concluded that EPE influenced the follicles growth, and it can be used in other biotechnologies, with greater utilization of equine ovarian follicular reserve.(AU)


Assuntos
Animais , Feminino , Corpo Lúteo/irrigação sanguínea , Corpo Lúteo/diagnóstico por imagem , Cavalos/fisiologia , Folículo Ovariano/irrigação sanguínea , Folículo Ovariano/diagnóstico por imagem , Fluxo Sanguíneo Regional/fisiologia , Superovulação , Ultrassonografia Doppler em Cores/veterinária
4.
Genes Immun ; 18(1): 33-41, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28053321

RESUMO

Cytokines expression can be influenced by polymorphisms in their respective coding genes. We associated the CTI/TTD haplotype (Hap-1) and TCI/CCI haplotype (Hap-2) in the IL4 gene formed by the -590, +33 and variable number of tandem repeat polymorphisms with the severity of chronic periodontitis in humans. The functionality of these IL4 haplotypes in the response of immune cells to phorbol 12-myristate 13-acetate (PMA) with Ionomycin and IL-1ß (as inflammatory stimuli) was evaluated. Gene expression (quantitative real-time PCR), profile of secreted cytokines (multiplex) and phenotypic polarization of T cells (flow cytometry) were the outcomes assessed. Green fluorescent protein reporter plasmid constructs containing specific IL4 haplotype were transiently transfected into JM cells to assess the influence of the individual haplotypes on promoter activity. In response to inflammatory stimuli the immune cells from Hap-1 haplotype had increased expression of anti-inflammatory IL4; conversely, the Hap-2 haplotype showed higher levels of pro-inflammatory cytokines. The haplotype CTI proved to be the most important for the regulation of IL4 promoter, regardless of the nature of the inflammatory stimulation; whereas the polymorphism in the promoter region had the least functional effect. In conclusion, IL4 haplotypes studied are functional and trigger opposite immune responses: anti-inflammatory (Hap-1) and pro-inflammatory (Hap-2). In addition, we identified the CTI haplotype as the main responsible for the regulation of IL4 transcriptional activity.


Assuntos
Biomarcadores/sangue , Periodontite Crônica/genética , Haplótipos/genética , Inflamação/genética , Interleucina-4/genética , Polimorfismo Genético/genética , Adulto , Estudos de Casos e Controles , Periodontite Crônica/sangue , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Humanos , Inflamação/sangue , Interleucina-4/sangue , Masculino , Prognóstico , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase em Tempo Real
5.
Scand J Immunol ; 81(1): 66-71, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25223881

RESUMO

Diabetes is associated with increased glucose levels and accumulation of glycated products. It is also associated with impairment in the immune response, such as increased susceptibility to infections. In this study, we assessed the possible interactions between TLR4 and RAGE signalling on apoptosis and on the expression of inflammatory cytokines in PBMC from individuals with and without diabetes. PBMCs were isolated from seven diabetic patients and six individuals without diabetes and stimulated in vitro with bacterial LPS (1 µg/ml) associated or not with BSA-AGE (200 µg/ml). This stimulation was performed for 6 h, both in the presence and in the absence of inhibitors of TLR4 (R. sphaeroides LPS, 20 µg/ml) and RAGE (blocking monoclonal antibody). Apoptosis at early and late stages was assessed by the annexin-V/PI staining using flow cytometry. Regulation of TNF-α and IL-10 gene expression was determined by RT-qPCR. PBMCs from diabetes patients tended to be more resistant apoptosis. There were no synergistic or antagonistic effects with the simultaneous activation of TLR4 and RAGE in PBMCs from either diabetes or non-diabetes group. Activation of TLR4 is more potent for the induction of TNF-α and IL-10; RAGE signalling had a negative regulatory effect on TNF-α expression induced by LPS. TLR and RAGE do not have relevant roles in apoptosis of PBMCs. The activation of TLR has greater role than RAGE in regulating the gene expression of IL-10 and TNF-α.


Assuntos
Apoptose/imunologia , Diabetes Mellitus/imunologia , Regulação da Expressão Gênica/imunologia , Leucócitos Mononucleares/imunologia , Receptor para Produtos Finais de Glicação Avançada/imunologia , Receptor 4 Toll-Like/imunologia , Adulto , Anticorpos Bloqueadores/imunologia , Anticorpos Monoclonais/imunologia , Feminino , Produtos Finais de Glicação Avançada/metabolismo , Produtos Finais de Glicação Avançada/farmacologia , Humanos , Inflamação/imunologia , Interleucina-10/biossíntese , Lipopolissacarídeos , Masculino , Pessoa de Meia-Idade , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Soroalbumina Bovina/farmacologia , Transdução de Sinais/imunologia , Receptor 4 Toll-Like/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
6.
J Evol Biol ; 27(11): 2520-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25307516

RESUMO

Parasite specialization on one or a few host species leads to a reduction in the total number of available host individuals, which may decrease transmission. However, specialists are thought to be able to compensate by increased prevalence in the host population and increased success in each individual host. Here, we use variation in host breadth among a community of avian Haemosporida to investigate consequences of generalist and specialist strategies on prevalence across hosts. We show that specialist parasites are more prevalent than generalist parasites in host populations that are shared between them. Moreover, the total number of infections of generalist and specialist parasites within the study area did not vary significantly with host breadth. This suggests that specialists can infect a similar number of host individuals as generalists, thus compensating for a reduction in host availability by achieving higher prevalence in a single host species. Specialist parasites also tended to infect older hosts, whereas infections by generalists were biased towards younger hosts. We suggest that this reflects different abilities of generalists and specialists to persist in hosts following infection. Higher abundance and increased persistence in hosts suggest that specialists are more effective parasites than generalists, supporting the existence of a trade-off between host breadth and average host use among these parasites.


Assuntos
Aves/parasitologia , Haemosporida/patogenicidade , Especificidade de Hospedeiro , Animais , Evolução Biológica , Haemosporida/fisiologia , Modelos Lineares , Modelos Biológicos
7.
Histol Histopathol ; 28(2): 269-76, 2013 02.
Artigo em Inglês | MEDLINE | ID: mdl-23275309

RESUMO

A single instillation of porcine pancreatic elastase (PPE) results in significant airspace enlargement on the 28th day after instillation, whereas cigarette smoke (CS) exposure requires 6 months to produce mild emphysema in rodents. Considering that there are differences in the pathogenesis of parenchymal destruction in these different experimental models, it is likely that there may be different patterns of extracellular matrix (ECM) remodeling. To evaluate ECM remodeling, C57BL/6 mice were submitted to either a nasal drop of PPE (PPE 28 Days) or exposed for 6 months to cigarette smoke (CS 6 months). Control groups received either an intranasal instillation of saline solution (Saline 28 Days) or remained without any smoke inhalation for six months (Control 6 months). We measured the mean linear intercept and the volume proportion of collagen type I, collagen type III, elastin and fibrillin. We used emission-scanning confocal microscopy to verify the fiber distribution. Both models induced increased mean linear intercept in relation to the respective controls, being larger in the elastase model in relation to the CS model. In the CS model, emphysema was associated with an increase in the volume proportion of fibrillin, whereas in the PPE model there was an increase in the parenchymal elastin content. In both models, there was an increase in collagen type III, which was higher in the CS-exposed mice. We concluded that ECM remodeling is different in the two most used experimental models of emphysema.


Assuntos
Modelos Animais de Doenças , Enfisema/induzido quimicamente , Enfisema/patologia , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Elastase Pancreática/efeitos adversos , Fumar/efeitos adversos , Animais , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Elastina/metabolismo , Enfisema/metabolismo , Fibrilinas , Imuno-Histoquímica/métodos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microscopia Confocal , Suínos
8.
Clin Exp Allergy ; 42(10): 1459-71, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22994343

RESUMO

BACKGROUND: Airway inflammation in asthma involves innate immune responses. Toll-like receptors (TLRs) and thymic stromal lymphopoietin (TSLP) are thought to be involved in airway inflammation, but their expression in asthmatics' both large and small airways has not been investigated. OBJECTIVE: To analyse the expression of TLR2, TLR3, TLR4 and TSLP in large and small airways of asthmatics and compare their expression in smoking and non-smoking asthmatics; to investigate whether TLR expression is associated with eosinophilic or neutrophilic airway inflammation and with Mycoplasma pneumoniae and Chlamydophila pneumoniae infection. METHODS: Using immunohistochemistry and image analysis, we investigated TLR2, TLR3, TLR4 and TSLP expression in large and small airways of 24 victims of fatal asthma, FA, (13 non-smokers, 11 smokers) and nine deceased control subjects (DCtrl). TLRs were also measured in 18 mild asthmatics (MA) and 12 healthy controls (HCtrl). M. pneumoniae and C. pneumoniae in autopsy lung tissue were analysed using real-time polymerase chain reaction. Airway eosinophils and neutrophils were measured in all subjects. RESULTS: Fatal asthma patients had higher TLR2 in the epithelial and outer layers of large and small airways compared with DCtrls. Smoking asthmatics had lower TLR2 levels in the inner and outer layers of the small airways than non-smoking asthmatics. TSLP was increased in the epithelial and outer layers of the large airways of FA. FA patients had greater TLR3 expression in the outer layer of large airways and greater TLR4 expression in the outer layer of small airways. Eosinophilic airway inflammation was associated with TLR expression in the epithelium of FA. No bacterial DNA was detected in FA or DCtrls. MA and HCtrls had only a small difference in TLR3 expression. CONCLUSIONS AND CLINICAL RELEVANCE: Increased expression of TLR 2, 3 and 4 and TSLP in fatal asthma may contribute to the acute inflammation surrounding asthma deaths.


Assuntos
Asma/mortalidade , Citocinas/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 3 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Adulto , Asma/imunologia , Feminino , Humanos , Inflamação/imunologia , Pulmão/imunologia , Masculino , Pessoa de Meia-Idade , Regulação para Cima , Linfopoietina do Estroma do Timo
9.
Inhal Toxicol ; 24(7): 439-46, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22642293

RESUMO

To investigate the effects of repeated crack-cocaine inhalation on spermatogenesis of pubertal and mature Balb/c mice, ten young (Y(ex)) and ten adult (A(ex)) Balb/c mice were exposed to the smoke from 5 g of crack with 57.7% of pure cocaine in an inhalation chamber, 5 days/week for 2 months. The young (Y(c)) and adult (A(c)) control animals (n = 10) were kept in a specially built and controlled animal house facility. The morphologic analysis of both testes of all animals included the analysis of quantitative and qualitative histologic parameters to assess the effect of crack-cocaine on spermatogenesis and Leydig cells. Apoptosis was determined by immunolabeling with caspase-3 antibodies. Compared to the Y(c) animals, Y(ex) animals showed a significant reduction in the number of stage VII tubules per testis (p = 0.02), Sertoli cells (p < 0.001) and elongated spermatids (p = 0.001). Comparisons between the Y(ex) and A(ex) groups identified a significant reduction in the number of Sertoli cells (p < 0.001) and round spermatids (p < 0.001) in the Y(ex) group and a significant increase in apoptotic Leydig cells (p = 0.04) in the A(ex) group. The experimental results indicate that crack-cocaine smoke inhalation induced spermatogenesis disruption in chronically exposed mice, particularly in pubertal mice.


Assuntos
Envelhecimento/fisiologia , Cocaína Crack/toxicidade , Fumaça/efeitos adversos , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Administração por Inalação , Animais , Apoptose/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testículo/patologia
10.
Int J Sports Med ; 31(12): 906-12, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21072743

RESUMO

Airway epithelium plays important roles in the pathophysiology of asthma. Creatine supplementation (Cr) was shown to increase asthma features in a murine model of allergic asthma; however, the role of the airway epithelium in this inflammatory response is not known. BALB/c mice were divided into control, creatine supplementation, ovalbumin-sensitized (OVA) and OVA plus creatine supplementation groups. OVA sensitization occurred on days 0, 14, 28 and 42, and ovalbumin challenge from days 21-53. Cr was also given on days 21-53. Total and differential cells counts in BALF were evaluated. Quantitative epithelial expression of interleukin (IL)-4, IL-5, IL-13, CCL11, CCL5, CCL2, iNOS, VCAM-1, ICAM-1, NF-κB, VEGF, TGF-ß, IGF-1, EGFR, TIMP-1, TIMP-2, MMP-9, MMP-12 and arginase II were performed. Cr increased the number of total cells and eosinophils in BALF, the epithelial content of goblet cells and the epithelial expression of IL-5, CCL2, iNOS, ICAM-1, NF-κB, TGF-ß, TIMP-1 and MMP-9 when compared to the control group (p<0.05). Creatine supplementation also exacerbated goblet cell proliferation, and IL-5 and iNOS expression by epithelial cells compared to the OVA group (p<0.01). Creatine up-regulates the pro-inflammatory cascade and remodelling process in this asthma model by modulating the expression of inflammatory mediators by epithelial cells.


Assuntos
Asma/etiologia , Creatina/toxicidade , Células Epiteliais/metabolismo , Mediadores da Inflamação/metabolismo , Animais , Asma/fisiopatologia , Líquido da Lavagem Broncoalveolar/química , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Caliciformes/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Fatores de Tempo
11.
Acta Reumatol Port ; 35(1): 82-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20518148

RESUMO

Tenosynovitis caused by tuberculosis (TB) is a rare presentation of this disease usually reported in immunocompromised patients. We describe a patient diagnosed with TB tenosynovitis of the left upper limb with no history of immunodeficiency. Although appearing in an endemic area the time to diagnosis was 6 years due to the absence of acid-fast stained bacilli in the first cultures despite histopathology showing a granulomatous lesion. Institution of pharmacological treatment and surgical debridément led to improvement within one month. The authors emphasize the need for early intervention in order to halt disease progression and avoid sequelae.


Assuntos
Síndrome do Túnel Carpal/microbiologia , Tenossinovite/microbiologia , Tuberculose/complicações , Feminino , Humanos , Pessoa de Meia-Idade
12.
Braz J Biol ; 69(2): 397-404, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19675945

RESUMO

Epidemiological studies have implicated maternal protein-calorie deficiency as an important public health problem in developing countries. Over the last decades, a remarkable diffusion of electricity and an increased level of the electromagnetic field (EMF) in the environment have characterized modern societies. Therefore, researchers are concerned with the biological effects of 50-60 Hz, EMF. The aim of this paper is to show the effects of EMF of 60 Hz, 3 muT, exposure for two hours per day in the regulation of the hormonal and metabolic concentrations in pregnant rats, which were fed by Regional Basic Diet (RBD) during their pregnancy as compared with pregnant rats fed a standard diet. Pregnant rats exposed to EMF of 60 Hz, 3 muT, over the pregnancy and fed with RBD presented an increase in glucose release when compared with the Group subjected only to the RBD ration. Rats fed RBD presented a decrease in their insulin and cortisol serum levels when compared with the Group fed with casein. The T3 and T4 concentrations presented the greatest variation among the Groups. The relation T4:T3 was much exaggerated in the Group subjected to RDB and exposed to EMF when compared to the others. In conclusion, the group subjected to the association of EMF and undernutrition suffered a decrease in its serum concentration of T4 and T3 when compared to the well-nourished group and the relationship T4:T3 in the former group was almost eighteen-fold the later one.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/sangue , Desnutrição Proteico-Calórica/sangue , Animais , Feminino , Hidrocortisona/sangue , Hidrocortisona/efeitos da radiação , Insulina/sangue , Insulina/efeitos da radiação , Gravidez , Ratos , Ratos Wistar , Tiroxina/sangue , Tiroxina/efeitos da radiação , Fatores de Tempo , Tri-Iodotironina/sangue , Tri-Iodotironina/efeitos da radiação
13.
Int J Sports Med ; 30(9): 684-90, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19569010

RESUMO

We recently demonstrated that creatine supplementation increased some features of lung allergic sensitization in mice. On the other hand, other studies have shown that aerobic exercise inhibited allergic airway inflammation and remodeling. We hypothesized that aerobic exercise may decrease the exacerbatory effects of the creatine supplementation in a murine model of asthma. Balb/c mice were divided into six groups: Control, Creatine (Cr), Low Intensity Exercise+Creatine (Low+Cr), Ovalbumin (OVA), Ovalbumin+Creatine (OVA+Cr) and Ovalbumin+Creatine+Low Intensity Exercise (OVA+Cr+Low). OVA-sensitized groups were sensitized with OVA intraperitoneal injections (days 0, 14, 28, and 42). Aerosol challenge (OVA 1%) and Cr treatment (0.5 g/kg/day) were initiated on Day 21 until Day 53. Low intensity exercise began on day 22 and was sustained until day 50. Low intensity exercise in the presence of creatine supplementation in sensitized mice resulted in a decreased number of eosinophils in BALF (p<0.001) and in the airways (p<0.001), and a decreased density of inflammatory cells positive to IL-4 (p<0.001) and IL-5 (p<0.001), airway collagen (p<0.001) and elastic fibers (p<0.001) content, airway smooth muscle thickness (p<0.001) and bronchoconstriction index (p<0.05) when compared with OVA+Cr group. These results suggest that aerobic exercise reduces the exacerbatory effects of creatine supplementation in chronically sensitized mice.


Assuntos
Asma/prevenção & controle , Creatina/toxicidade , Condicionamento Físico Animal/fisiologia , Animais , Asma/etiologia , Asma/fisiopatologia , Líquido da Lavagem Broncoalveolar/imunologia , Broncoconstrição/imunologia , Modelos Animais de Doenças , Eosinófilos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Músculo Liso/metabolismo , Ovalbumina/imunologia
14.
Braz. j. biol ; 69(2): 397-404, May 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-519185

RESUMO

Epidemiological studies have implicated maternal protein-calorie deficiency as an important public health problem in developing countries. Over the last decades, a remarkable diffusion of electricity and an increased level of the electromagnetic field (EMF) in the environment have characterized modern societies. Therefore, researchers are concerned with the biological effects of 50-60 Hz, EMF. The aim of this paper is to show the effects of EMF of 60 Hz, 3 μT, exposure for two hours per day in the regulation of the hormonal and metabolic concentrations in pregnant rats, which were fed by Regional Basic Diet (RBD) during their pregnancy as compared with pregnant rats fed a standard diet. Pregnant rats exposed to EMF of 60 Hz, 3 μT, over the pregnancy and fed with RBD presented an increase in glucose release when compared with the Group subjected only to the RBD ration. Rats fed RBD presented a decrease in their insulin and cortisol serum levels when compared with the Group fed with casein. The T3 and T4 concentrations presented the greatest variation among the Groups. The relation T4:T3 was much exaggerated in the Group subjected to RDB and exposed to EMF when compared to the others. In conclusion, the group subjected to the association of EMF and undernutrition suffered a decrease in its serum concentration of T4 and T3 when compared to the well-nourished group and the relationship T4:T3 in the former group was almost eighteen-fold the later one.


Estudos epidemiológicos têm mostrado que a deficiência proteico-calórica é um importante problema nos países em desenvolvimento. Durante as últimas décadas, a sociedade moderna tem sido caracterizada pelo aumento no número de equipamentos elétricos e como consequência um aumento no nível do campo eletromagnético (CEM) no ambiente. No entanto, os pesquisadores estão preocupados com os efeitos biológicos dos CEM de 50-60 Hz. O objetivo deste artigo é mostrar os efeitos do CEM de 60 Hz, 3 μT, nas concentrações hormonais e metabólicas de ratas prenhes, expostas duas horas por dia ao CEM, alimentadas pela Dieta Básica Regional (DBR) comparando com ratas submetidas às mesmas condições, mas alimentas com dieta padrão. Ratas prenhes expostas ao CEM de 60 Hz, 3 μT, durante a prenhez e alimentadas com a DBR apresentaram um aumento na liberação de glicose quando comparadas com o grupo alimentado pela DBR sem CEM. As ratas alimentadas pela DBR apresentaram uma diminuição nos níveis de insulina e cortisol quando comparadas com o grupo alimentado pela caseína. As concentrações de T3 e T4 apresentaram a maior variação entre os grupos. A relação T4:T3 foi muito exagerada no grupo alimentado pela DBR e exposto ao CEM quando comparado com os outros. Conclusão, os animais que foram submetidos à desnutrição e ao CEM sofreram uma diminuição na concentração sérica de T4 e T3 quando comparados com os animais bem nutridos e a relação T4:T3 no primeiro grupo foi quase 18 vezes a relação de T4:T3 no grupo bem nutrido.


Assuntos
Animais , Feminino , Gravidez , Ratos , Campos Eletromagnéticos/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/sangue , Desnutrição Proteico-Calórica/sangue , Hidrocortisona/sangue , Hidrocortisona/efeitos da radiação , Insulina/sangue , Insulina/efeitos da radiação , Ratos Wistar , Fatores de Tempo , Tiroxina/sangue , Tiroxina/efeitos da radiação , Tri-Iodotironina/sangue , Tri-Iodotironina/efeitos da radiação
15.
Artigo em Português | LILACS | ID: lil-536686

RESUMO

Os objetivos do estudo foram desenvolver e avaliar a estabilidade físico-química de emulsões O/A contendo cetoconazol a 2,0% e determinar seu perfil de liberação in vitro. As formulações foram preparadas com bases auto-emulsionáveis com diferentes características químicas. A estabilidade do sistema foi avaliada de acordo com o Guia para Realização de Testes de Estabilidade em Produtos Farmacêuticos, utilizando diferentes temperaturas (4ºC, 37ºC e 45ºC) por um período de tempo de três meses. Os parâmetros avaliados durante o ensaio foram: as características organolépticas,o pH, o comportamento reológico e a concentração do ativo. A emulsão considerada estável foi submetida ao ensaio de liberação in vitro utilizando célula de difusão de Franz. A quantificação do cetoconazol na formulação e na solução receptora foi realizada por método espectrofotométrico no ultravioleta a 244 nm. Dentre as formulações testadas, somente aquela preparada com álcool cetoestearílico e estearato de polietilenoglicol (PEG20) manteve suas características físico-químicas estáveis durante o teste. O estudo de liberação in vitro demonstrou que o fármaco foi liberado do sistema gradualmente no decorrer do tempo, apresentando uma cinética pseudo zero ordem.


The goal of this work was to develop and assess the physicochemical stability of O/W emulsions containing 2.0% ketoconazole and to determine their in vitro release profile. These formulations were prepared with self-emulsifying bases that differed in their chemical characteristics. The stability of the system was assessed, as recommended in the Guide to Drug Product Stability Tests, over 3 months at 3 different temperatures (4ºC, 37ºC and 45ºC). The characteristics assessed during the test were the organoleptic properties, pH, rheological behavior and drug concentration. The most stable emulsion was subjected to an in vitro release test in a Franz diffusion cell system. The ketoconazole in both the formulation and receptor phase was determined by UV spectrophotometry at 244 nm. The O/W emulsion prepared with cetearyl alcohol and polyethylene glycol (PEG20) stearate was the only one that maintained its physicochemical characteristics throughout the test. The in vitro release test demonstrated that the drug was released gradually, exhibiting pseudo zero-order kinetics.


Assuntos
Antifúngicos , Estabilidade de Medicamentos
16.
Braz J Biol ; 68(3): 641-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18833487

RESUMO

The aim of the present study was to observe how the exposition of pregnant rats to an electromagnetic field (EMF), with frequency of 60 Hz, and a magnetic field of 3 microT for 2 hours per day and/or using the so-called Regional Basic Diet (RBD), influenced the somatic maturation in their offspring. Four groups were formed: Group A (casein), B (casein and EMF), C (RBD) and D (RBD and EMF). The diet manipulation occurred during pregnancy. The somatic maturation indexes--assessed daily between 12:00 AM and 2:00 PM--were: Eye Opening (EO), Auricle Opening (AO), Auditory Canal Opening (ACO), Low Incisor Eruption (LIE), and Upper Incisor Eruption (UIE). The association between EMF and deficient diet caused a delay in all Somatic Maturation Indexes (SMI) and the RBD caused delay only in the AO. Furthermore, the EMF caused delay in AO, ACO, LIE. In relation to the body weight, the EMF associated with the deficient diet caused change in the twenty-first day of life. The RBD, during pregnancy, caused lower body weight in the offspring in the first and third day of life. The body weight of the offspring whose mothers were fed casein and exposed to the EMF during pregnancy was lower in the third and sixth day of life. In conclusion, the EMF associated with under-nutrition caused delay in all SMI. In relation to the body weight, the EMF associated with under-nutrition caused a decrease in the body weight at the sixth day of life.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Desnutrição Proteico-Calórica/complicações , Distúrbios Somatossensoriais/etiologia , Animais , Feminino , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Wistar , Fatores de Tempo
17.
Braz. j. biol ; 68(3): 641-648, Aug. 2008. tab
Artigo em Inglês | LILACS | ID: lil-493584

RESUMO

The aim of the present study was to observe how the exposition of pregnant rats to an electromagnetic field (EMF), with frequency of 60 Hz, and a magnetic field of 3 µT for 2 hours per day and/or using the so-called Regional Basic Diet (RBD), influenced the somatic maturation in their offspring. Four groups were formed: Group A (casein), B (casein and EMF), C (RBD) and D (RBD and EMF). The diet manipulation occurred during pregnancy. The somatic maturation indexes - assessed daily between 12:00 AM and 2:00 PM - were: Eye Opening (EO), Auricle Opening (AO), Auditory Canal Opening (ACO), Low Incisor Eruption (LIE), and Upper Incisor Eruption (UIE). The association between EMF and deficient diet caused a delay in all Somatic Maturation Indexes (SMI) and the RBD caused delay only in the AO. Furthermore, the EMF caused delay in AO, ACO, LIE. In relation to the body weight, the EMF associated with the deficient diet caused change in the twenty-first day of life. The RBD, during pregnancy, caused lower body weight in the offspring in the first and third day of life. The body weight of the offspring whose mothers were fed casein and exposed to the EMF during pregnancy was lower in the third and sixth day of life. In conclusion, the EMF associated with under-nutrition caused delay in all SMI. In relation to the body weight, the EMF associated with under-nutrition caused a decrease in the body weight at the sixth day of life.


O objetivo deste estudo foi observar a influência do campo eletromagnético (CEM), com freqüência de 60Hz, campo magnético de 3 µT, durante 2 horas por dia, associado ou não à dieta básica regional (DBR) no desenvolvimento somático da prole. Quatro grupos foram formados: Grupo A (caseína), B (caseína e CEM), C (DBR) e D (DBR e CEM). A manipulação dietética ocorreu durante a prenhez. Os índices de maturação somática - Abertura dos Olhos (AO), Abertura do Pavilhão Auditivo (APA), Abertura do Conduto Auditivo (ACA), Erupção do Incisivo Inferior (EII), e Erupção do Incisivo Superior (EIS) - foram avaliados diariamente entre 12 e 14 horas. A associação entre o CEM e a dieta deficiente causou retardo em todos os índices de maturação somática (IMS) e a DBR causou retardo somente na APA. O CEM causou retardo na APA, ACA, EII. Em relação ao peso corporal, o CEM associado à dieta deficiente causou mudanças no 21º dia de vida. A DBR, durante a prenhez, causou diminuição do peso corporal dos filhotes no 1º e no 3º dia de vida. O peso corporal dos filhotes, cujas mães foram alimentadas pela caseína e expostas ao CEM, durante a prenhez, apresentaram uma diminuição no 3º e 6º dia de vida. Conclusão: o CEM, associado com a desnutrição, causou retardo em todos os IMS. Em relação ao peso corporal, o CEM, associado à desnutrição, causou uma diminuição no peso corporal no 6º dia de vida.


Assuntos
Animais , Feminino , Masculino , Gravidez , Ratos , Campos Eletromagnéticos/efeitos adversos , Desnutrição Proteico-Calórica/complicações , Distúrbios Somatossensoriais/etiologia , Efeitos Tardios da Exposição Pré-Natal , Ratos Wistar , Fatores de Tempo
18.
Ann Trop Med Parasitol ; 102(4): 357-65, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18510816

RESUMO

In order to assess the epidemiological and clinical characteristics and changing nutritional status of infants suffering from acute diarrhoea, 103 infants with such diarrhoea and the same number of age-matched controls were investigated at the Universidade Federal do Rio Grande do Norte's Paediatric Hospital, in north-eastern Brazil. Each child with diarrhoea was given oral rehydration or, in the severe cases, intravenous rehydration. Each subject was checked for enteropathogens and his or her weight, height and weight-for-height, weight-for-age and height-for-age Z-scores were evaluated immediately after any clinical dehydration had been corrected and 30 days later. In the infants aged <6 months, a diet that included foods other than breast milk (odds ratio=9.41), including one in which breast milk was supplemented with other foods (odds ratio=4.69), was found to be statistically associated with diarrhoea. The enteropathogens found most commonly in the children with diarrhoea were rotavirus (36.9%), enteropathogenic Escherichia coli (11.6%) and Shigella (11.6%). Just four (5.2%) of the 77 cases with adequate follow-up showed persistent diarrhoea. At presentation or as soon as any clinical dehydration had been corrected, the infants with diarrhoea had significantly lower weights and weight-for-height and weight-for-age Z-scores than the controls. Thirty days later, however, the weight-for-height and weight-for-age Z-scores of the cases had increased significantly, to the point when they were not significantly different from the baseline values for the controls. The negative consequences of diarrhoea on weight-for-height and weight-for-age Z-scores and the recovery of these parameters after 30 days with rehydration reflect the acute but reversible influence of diarrhoea on infant nutritional status.


Assuntos
Desidratação , Diarreia Infantil , Estado Nutricional/fisiologia , Doença Aguda , Distribuição por Idade , Animais , Antropometria/métodos , Brasil/epidemiologia , Aleitamento Materno , Estudos de Casos e Controles , Desidratação/diagnóstico , Desidratação/epidemiologia , Desidratação/prevenção & controle , Diarreia Infantil/diagnóstico , Diarreia Infantil/epidemiologia , Diarreia Infantil/prevenção & controle , Disenteria Bacilar/epidemiologia , Infecções por Escherichia coli/epidemiologia , Fezes/parasitologia , Humanos , Lactente , Avaliação Nutricional , Fatores de Risco
19.
IEEE Trans Neural Netw ; 12(4): 755-64, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18249911

RESUMO

The goal of this paper is to test and model nonlinearities in several monthly exchange rates time series. We apply two different nonlinear alternatives, namely: the artificial neural-network time series model estimated with Bayesian regularization; and a flexible smooth transition specification, called the neuro-coefficient smooth transition autoregression. The linearity test rejects the null hypothesis of linearity in 10 out of 14 series. We compare, using different measures, the forecasting performance of the nonlinear specifications with the linear autoregression and the random walk models.

20.
IEEE Trans Neural Netw ; 11(6): 1402-12, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-18249864

RESUMO

This paper considers a linear model with time varying parameters controlled by a neural network to analyze and forecast nonlinear time series.We show that this formulation, called neural coefficient smooth transition autoregressive (NCSTAR) model, is in close relation to the threshold autoregressive (TAR) model and the smooth transition autoregressive (STAR) model with the advantage of naturally incorporating linear multivariate thresholds and smooth transitions between regimes. In our proposal, the neuralnetwork output is used to induce a partition of the input space, with smooth and multivariate thresholds. This also allows the choice of good initial values for the training algorithm.

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