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1.
Stem Cell Res Ther ; 15(1): 63, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38438875

RESUMO

BACKGROUND: Spinal ventral root avulsion results in massive motoneuron degeneration with poor prognosis and high costs. In this study, we compared different isoforms of basic fibroblast growth factor 2 (FGF2), overexpressed in stably transfected Human embryonic stem cells (hESCs), following motor root avulsion and repair with a heterologous fibrin biopolymer (HFB). METHODS: In the present work, hESCs bioengineered to overexpress 18, 23, and 31 kD isoforms of FGF2, were used in combination with reimplantation of the avulsed roots using HFB. Statistical analysis was conducted using GraphPad Prism software with one-way or two-way ANOVA, followed by Tukey's or Dunnett's multiple comparison tests. Significance was set at *p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001. RESULTS: For the first set of experiments, rats underwent avulsion of the ventral roots with local administration of HFB and engraftment of hESCs expressing the above-mentioned FGF2 isoforms. Analysis of motoneuron survival, glial reaction, and synaptic coverage, two weeks after the lesion, indicated that therapy with hESCs overexpressing 31 kD FGF2 was the most effective. Consequently, the second set of experiments was performed with that isoform, so that ventral root avulsion was followed by direct spinal cord reimplantation. Motoneuron survival, glial reaction, synaptic coverage, and gene expression were analyzed 2 weeks post-lesion; while the functional recovery was evaluated by the walking track test and von Frey test for 12 weeks. We showed that engraftment of hESCs led to significant neuroprotection, coupled with immunomodulation, attenuation of astrogliosis, and preservation of inputs to the rescued motoneurons. Behaviorally, the 31 kD FGF2 - hESC therapy enhanced both motor and sensory recovery. CONCLUSION: Transgenic hESCs were an effective delivery platform for neurotrophic factors, rescuing axotomized motoneurons and modulating glial response after proximal spinal cord root injury, while the 31 kD isoform of FGF2 showed superior regenerative properties over other isoforms in addition to the significant functional recovery.


Assuntos
Células-Tronco Embrionárias , Fator 2 de Crescimento de Fibroblastos , Humanos , Animais , Ratos , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/farmacologia , Peso Molecular , Raízes Nervosas Espinhais , Biopolímeros , Fibrina , Isoformas de Proteínas/genética
2.
Phys Rev E ; 108(1-1): 014308, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37583232

RESUMO

We discuss the majority vote model coupled with scale-free networks and investigate its critical behavior. Previous studies point to a nonuniversal behavior of the majority vote model, where the critical exponents depend on the connectivity. At the same time, the effective dimension D_{eff} is unity for a degree distribution exponent 5/2<γ<7/2. We introduce a finite-size theory of the majority vote model for uncorrelated networks and present generalized scaling relations with good agreement with Monte Carlo simulation results. Our finite-size approach has two sources of size dependence: an external field representing the influence of the mass media on consensus formation and the scale-free network cutoff. The critical exponents are nonuniversal, dependent on the degree distribution exponent, precisely when 5/2<γ<7/2. For γ≥7/2, the model is in the same universality class as the majority vote model on Erdos-Rényi random graphs. However, for γ=7/2, the critical behavior includes additional logarithmic corrections.

3.
Chemosphere ; 222: 364-370, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30710762

RESUMO

Two recombinant protease inhibitors from Bauhinia bauhinioides, rBbKI (kallikrein inhibitor) and rBbCI (cruzipain inhibitor) were evaluated for insecticidal activity against workers and soldiers of Nasutitermes corniger (order: Isoptera; family: Termitidae) through the inhibitors' effect on the insect's gut enzymes. The inhibitor rBbKI was more effective than rBbCI in inhibiting the termite's gut enzymes. The kallikrein inhibitor showed termiticidal activity in workers with an LC50 of 0.9 mg mL-1 after 4 days. Conversely, rBbKI did not affect the survival of soldiers and rBbCI did not show termiticidal activity against N. corniger. The two inhibitors showed different specificity towards the termite's gut enzymes, representing interesting tools to characterize N. corniger enzymes. The different effects of rBbKI and rBbCI on the termite's enzymes and survival may be linked to slight structural differences between these inhibitors.


Assuntos
Bauhinia/química , Inseticidas/farmacologia , Isópteros/enzimologia , Inibidores de Proteases/farmacologia , Animais , Cisteína Endopeptidases , Humanos , Calicreínas/antagonistas & inibidores , Proteínas de Protozoários/antagonistas & inibidores , Especificidade por Substrato
4.
Int J Biol Macromol ; 127: 425-432, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30654040

RESUMO

Hepatocellular carcinoma incidence rates have increased worldwide, which encouraged the development of new chemotherapeutic drugs. l-Amino acid oxidases from snake venoms are cytotoxic towards human tumor cells in in vitro monoculture systems, which do not simulate the tumor microenvironment. We examined the antitumor potential of BjussuLAAO-II, an l-amino acid oxidase from Bothrops jararacussu venom, in hepatocarcinoma cells (HepG2) in monoculture and co-culture with human umbilical vein endothelial cells (HUVEC) in vitro. All the concentrations tested (0.25-5.00 µg/mL) were cytotoxic (MTT and clonogenic survival assays) towards HepG2 and HUVEC cells in monoculture, and increased oxidative stress by 2',7'-dichlorofluorescin diacetate fluorescence assay. Only 1.00 and 5.00 µg/mL exerted these effects in HepG2 cells co-cultured with HUVEC cells, and were genotoxic (comet assay) to HUVEC cells in monoculture. BjussuLAAO-II at 5.00 µg/mL induced DNA, but not chromosomal damage (micronucleus assay) in HepG2 cells in mono- and co-culture. The cytotoxicity and genotoxicity was more pronounced in monoculture, indicating that the tumor microenvironment influences the cellular response. BjussuLAAO-II caused cell death and DNA damage in HepG2 cells in vitro by inducing oxidative stress. Therefore, BjussuLAAO-II is a promising molecule for the development of new antitumor drugs.


Assuntos
Bothrops , Venenos de Crotalídeos , Citotoxinas , Dano ao DNA , Células Endoteliais da Veia Umbilical Humana/metabolismo , L-Aminoácido Oxidase , Estresse Oxidativo/efeitos dos fármacos , Animais , Técnicas de Cocultura , Venenos de Crotalídeos/química , Venenos de Crotalídeos/farmacologia , Citotoxinas/química , Citotoxinas/farmacologia , Células Hep G2 , Humanos , L-Aminoácido Oxidase/química , L-Aminoácido Oxidase/farmacologia
5.
J Neuroinflammation ; 15(1): 230, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30107848

RESUMO

BACKGROUND: Treatment of spinal cord injury is dependent on neuronal survival, appropriate synaptic circuit preservation, and inflammatory environment management. In this sense, mesenchymal stem cell (MSC) therapy is a promising tool that can reduce glial reaction and provide trophic factors to lesioned neurons. METHODS: Lewis adult female rats were submitted to a unilateral ventral funiculus cut at the spinal levels L4, L5, and L6. The animals were divided into the following groups: IA (intramedullary axotomy), IA + DMEM (Dulbecco's modified Eagle's medium), IA + FS (fibrin sealant), IA + MSC (106 cells), and IA + FS + MSC (106 cells). Seven days after injury, qPCR (n = 5) was performed to assess gene expression of VEGF, BDNF, iNOS2, arginase-1, TNF-α, IL-1ß, IL-6, IL-10, IL-4, IL-13, and TGF-ß. The cellular infiltrate at the lesion site was analyzed by hematoxylin-eosin (HE) staining and immunohistochemistry (IH) for Iba1 (microglia and macrophage marker) and arginase-1. Fourteen days after injury, spinal alpha motor neurons (MNs), evidenced by Nissl staining (n = 5), were counted. For the analysis of astrogliosis in spinal lamina IX and synaptic detachment around lesioned motor neurons (GAP-43-positive cells), anti-GFAP and anti-synaptophysin immunohistochemistry (n = 5) was performed, respectively. Twenty-eight days after IA, the gait of the animals was evaluated by the walking track test (CatWalk; n = 7). RESULTS: The site of injury displayed strong monocyte infiltration, containing arginase-1-expressing macrophages. The FS-treated group showed upregulation of iNOS2, arginase-1, proinflammatory cytokine (TNF-α and IL-1ß), and antiinflammatory cytokine (IL-10, IL-4, and IL-13) expression. Thus, FS enhanced early macrophage recruitment and proinflammatory cytokine expression, which accelerated inflammation. Rats treated with MSCs displayed high BDNF-positive immunolabeling, suggesting local delivery of this neurotrophin to lesioned motoneurons. This BDNF expression may have contributed to the increased neuronal survival and synapse preservation and decreased astrogliosis observed 14 days after injury. At 28 days after lesion, gait recovery was significantly improved in MSC-treated animals compared to that in the other groups. CONCLUSIONS: Overall, the present data demonstrate that MSC therapy is neuroprotective and, when associated with a FS, shifts the immune response to a proinflammatory profile.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Regulação da Expressão Gênica/fisiologia , Imunomodulação/fisiologia , Células-Tronco Mesenquimais/fisiologia , Neurônios Motores/metabolismo , Neuroproteção/fisiologia , Traumatismos da Medula Espinal , Animais , Arginase/genética , Arginase/metabolismo , Axotomia/métodos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Adesivo Tecidual de Fibrina/uso terapêutico , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos Lew , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia , Adesivos Teciduais/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Hum Exp Toxicol ; 37(3): 275-284, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29233032

RESUMO

Cereal-based diets formulated as semi-purified diets can provide flexibility for researchers, enabling open controlled formulas, besides being cheaper than purified diets. Seeking to widen the researchers' options in their experimental design developments, we aimed at assaying the chemical score, growth performance and protein utilization of nine semi-purified experimental chows. These diets were formulated at 17.8%, 12% and 8% protein contents, using three variations of ingredients for each one, as follows: casein (C), casein+soybean meal (C+S, 1:1 w/w protein) and casein+soybean meal+corn gluten meal (C+S+G, 1:1:1 w/w protein), without cysteine supplementation and setting casein 17.8% (AIN-93G) as reference diet. The diets C and C+S (17.8%) had the Cys as the limiting amino acid once the addition of gluten turns the Lys as second limiting. All diets had the potential for promoting growth with body mass gain, feed conversion ratio (FCR; chow consumed per body weight gain, average 3.12) and feed efficiency ratio (FER; body weight gain per chow consumed, average 0.3), except for C+S+G 8% (FCR = 6 g; FER = 0.13). These variations were mainly due to the protein amounts independently from the protein ingredient used and could characterize the C+S+G 8% as unable to support growth. For the other parameters (digestibility, net protein ratio, net protein utilization and protein efficiency ratio), there were no relevant differences between the diets. We can conclude that 17.8%, 12% and 8% chows (C and C+S) allowed a proper combination of ingredients from the point of view of palatability, nutrient availability/utilization, metabolic processes, growth performance and feed utilization parameters.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Proteínas na Dieta/administração & dosagem , Grão Comestível , Animais , Caseínas/administração & dosagem , Caseínas/metabolismo , Proteínas na Dieta/metabolismo , Ingestão de Alimentos , Metabolismo Energético , Estudos de Viabilidade , Glutens/administração & dosagem , Glutens/metabolismo , Masculino , Estado Nutricional , Valor Nutritivo , Ratos Wistar , Proteínas de Soja/administração & dosagem , Proteínas de Soja/metabolismo , Aumento de Peso , Zea mays
7.
Genet Mol Res ; 16(2)2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28613383

RESUMO

The Alcantarea patriae is a Bromeliaceae endemic to the inselbergs of the Atlantic Forest. This taxon, described in the year of 2007 by Versieux & Wanderley, presents restricted and fragmented distribution outside conservation units. Studies to evaluate the genetic structure of its populations can contribute to the conservation and management strategies for the species. In this study, 31 microsatellite markers, descriptive to six different Bromeliaceae species, were evaluated by cross-amplification tests in 20 individuals of A. patriae. The individuals were collected in the district of Vila Cruzeiro, in the municipality of Jerônimo Monteiro. Twelve markers were polymorphic and 10 monomorphic, with an amplification success rate of 71%. The displayed polymorphism information content was considered high, indicating that the selected markers are informative. The values found for the fixation index were positive and indicated the occurrence of inbreeding. The mean number of alleles was 4.66 (3-6), the mean expected and observed heterozygosities were 0.6605 and 0.4618, respectively. The detection of polymorphic markers was important for future studies of diversity and genetic structuring of natural populations and for germplasm bank creation aiming to contribute to in situ and ex situ conservations of A. patriae.


Assuntos
Bromeliaceae/genética , Repetições de Microssatélites , Amplificação de Genes , Frequência do Gene , Heterozigoto , Endogamia , Polimorfismo Genético
8.
Vet J ; 217: 119-125, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27810202

RESUMO

Sheep are used in many countries as food and for manufacturing bioproducts. However, when these animals consume animal by-products (ABP), which is widely prohibited, there is a risk of transmitting scrapie - a fatal prion disease in human beings. Therefore, it is essential to develop sensitive methods to detect previous ABP intake to select safe animals for producing biopharmaceuticals. We used stable isotope ratio mass spectrometry (IRMS) for 13C and 15N to trace animal proteins in the serum of three groups of sheep: 1 - received only vegetable protein (VP) for 89 days; 2 - received animal and vegetable protein (AVP); and 3 - received animal and vegetable protein with animal protein subsequently removed (AVPR). Groups 2 and 3 received diets with 30% bovine meat and bone meal (MBM) added to a vegetable diet (from days 16-89 in the AVP group and until day 49 in the AVPR group, when MBM was removed). The AVPR group showed 15N equilibrium 5 days after MBM removal (54th day). Conversely, 15N equilibrium in the AVP group occurred 22 days later (76th day). The half-life differed between these groups by 3.55 days. In the AVPR group, 15N elimination required 53 days, which was similar to this isotope's incorporation time. Turnover was determined based on natural 15N signatures. IRMS followed by turnover calculations was used to evaluate the time period for the incorporation and elimination of animal protein in sheep serum. The δ13C and δ15N values were used to track animal protein in the diet. This method is biologically and economically relevant for the veterinary field because it can track protein over time or make a point assessment of animal feed with high sensitivity and resolution, providing a low-cost analysis coupled with fast detection. Isotopic profiles could be measured throughout the experimental period, demonstrating the potential to use the method for traceability and certification assessments.


Assuntos
Ração Animal/análise , Dieta/veterinária , Proteínas na Dieta/análise , Espectrometria de Massas/veterinária , Ovinos , Animais , Isótopos de Carbono/análise , Espectrometria de Massas/métodos , Isótopos de Nitrogênio/análise
9.
Genet Mol Res ; 15(4)2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27813577

RESUMO

Some studies of polymorphisms in prostate cancer (PCa) analyze individuals in a uniform manner, regardless of genetic ancestry. However, PCa aggressiveness differs between subjects of African descent and those of European extraction. Thus, genetic ancestry analysis may be used to detect population stratification in case-control association studies. We genotyped 11 ancestry informative markers to estimate the contributions of African, European, and Amerindian ancestries in a case-control sample of 213 individuals from Bahia State, Northeast Brazil, including 104 PCa patients. We compared this data with self-reported ancestry and the stratification of cases by PCa aggressiveness according to Gleason score. A larger African genetic contribution (44%) was detected among cases, and a greater European contribution (61%) among controls. Self-declaration data revealed that 74% of PCa patients considered themselves non-white (black and brown), and 41.3% of controls viewed themselves as white. Our data showed a higher degree of European ancestry among fast-growing cancer cases than those of intermediate and slow development. This differs from many previous studies, in which the prevalence of African ancestry has been reported for all grades. Differences were observed between degrees of PCa aggressiveness in terms of genetic ancestry. In particular, the greater European contribution among patients with high-grade PCa indicates that a population's genetic structure can influence case-control studies. This investigation contributes to our understanding of the genetic basis of tumor aggressiveness among groups of different genetic ancestries, especially admixed populations, and has significant implications for the assessment of inter-population heterogeneity in drug treatment effects.


Assuntos
População Negra/genética , Etnicidade/genética , Genoma Humano , Neoplasias da Próstata/genética , Idoso , Brasil , Estudos de Casos e Controles , Frequência do Gene/genética , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Pigmentação/genética , População Branca/genética
10.
Bioorg Med Chem ; 24(18): 4228-4240, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27475533

RESUMO

In this study, we designed and synthesized a series of thiophen-2-iminothiazolidine derivatives from thiophen-2-thioureic with good anti-Trypanosoma cruzi activity. Several of the final compounds displayed remarkable trypanocidal activity. The ability of the new compounds to inhibit the activity of the enzyme cruzain, the major cysteine protease of T. cruzi, was also explored. The compounds 3b, 4b, 8b and 8c were the most active derivatives against amastigote form, with significant IC50 values between 9.7 and 6.03µM. The 8c derivative showed the highest potency against cruzain (IC50=2.4µM). Molecular docking study showed that this compound can interact with subsites S1 and S2 simultaneously, and the negative values for the theoretical energy binding (Eb=-7.39kcal·mol(-1)) indicates interaction (via dipole-dipole) between the hybridized sulfur sp(3) atom at the thiazolidine ring and Gly66. Finally, the results suggest that the thiophen-2-iminothiazolidines synthesized are important lead compounds for the continuing battle against Chagas disease.


Assuntos
Tiazolidinas/farmacologia , Tiofenos/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Cisteína Endopeptidases , Inibidores de Cisteína Proteinase/síntese química , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Cisteína Proteinase/toxicidade , Glicina/química , Camundongos , Simulação de Acoplamento Molecular , Octoxinol , Proteínas de Protozoários/antagonistas & inibidores , Tiazolidinas/síntese química , Tiazolidinas/toxicidade , Tiofenos/síntese química , Tiofenos/toxicidade , Tioureia/análogos & derivados , Tioureia/síntese química , Tioureia/farmacologia , Tioureia/toxicidade , Tripanossomicidas/síntese química , Tripanossomicidas/toxicidade
11.
Phys Rev E ; 94(6-1): 062305, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28085335

RESUMO

We describe the phenomenon of localization in the epidemic susceptible-infective-susceptible model on highly heterogeneous networks in which strongly connected nodes (hubs) play the role of centers of localization. We find that in this model the localized states below the epidemic threshold are metastable. The longevity and scale of the metastable outbreaks do not show a sharp localization transition; instead there is a smooth crossover from localized to delocalized states as we approach the epidemic threshold from below. Analyzing these long-lasting local outbreaks for a random regular graph with a hub, we show how this localization can be detected from the shape of the distribution of the number of infective nodes.


Assuntos
Epidemias/estatística & dados numéricos , Modelos Estatísticos , Surtos de Doenças/estatística & dados numéricos , Transmissão de Doença Infecciosa/estatística & dados numéricos , Humanos , Fatores de Tempo
12.
J Toxicol Environ Health A ; 75(16-17): 1070-80, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22852856

RESUMO

Keeping snakes in captivity to produce venom for scientific research and production of inputs is now a worldwide practice. Maintaining snakes in captivity involves capture, infrastructure investments, management techniques, and appropriate qualified personnel. Further, the success of the project requires knowledge of habitat, nutrition, and reproduction, and control of opportunistic infections. This study evaluated the management of snakes in three types of captivity (quarantine, intensive, and semiextensive) and diagnosed bacterial and fungal contaminants. A bacteriological profile was obtained by swabbing the oral and cloacal cavities, scales, and venoms of healthy adult snakes from Bothrops jararaca (Bj) and Crotalus durissus terrificus (Cdt). There was predominance of Enterobacteriaceae, especially non-fermenting Gram-negative bacilli excluding Pseudomonas spp and Gram- positive bacteria. Statistically, intensive captivity resulted in the highest number of bacterial isolates, followed by recent capture (quarantine) and by semiextensive captivity. No statistical difference was found between Bj and Cdt bacterial frequency. In vitro bacterial susceptibility testing found the highest resistance against the semisynthetic penicillins (amoxicillin and ampicillin) and highest sensitivity to amicacin and tobramycin aminoglycosides. To evaluate mycological profile of snakes from intensive captivity, samples were obtained from two healthy Bj and one B. moojeni, one B. pauloensis, and one Cdt showing whitish lesions on the scales suggestive of ringworm. Using conventional methods and DNA-based molecular procedures, five samples of Trichosporon asahii were identified. Despite the traditional role of intense captivity in ophidian venom production, semiextensive captivity was more effective in the present study by virtue of presenting superior control of bacterial and fungal transmission, easier management, lowest cost, and decreased rate of mortality; therefore, it should be considered as a good alternative for tropical countries.


Assuntos
Bactérias/classificação , Cloaca/microbiologia , Fungos/classificação , Boca/microbiologia , Serpentes/microbiologia , Animais , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Fungos/efeitos dos fármacos , Fungos/isolamento & purificação
13.
Artigo em Inglês | MEDLINE | ID: mdl-22401177

RESUMO

In 1956, Africanized bees began to spread in the American continent from southern Brazil, where original African bees mated with European bees. A few years later, in 1990, these Africanized bees reached the United States and were found in Texas. Currently, these hybrid bees are found in several North American states and will probably reach the Canadian border in the future. Although the presence of Africanized bees had produced positive effects on Brazilian economy, including improvement in crop pollination and in honey production, turning Brazil into a major exporter, the negative impacts-such as swarming, aggressive behavior, and the ability to mass attack-resulted in serious and fatal envenomation with humans and animals. Victims of bee attacks usually develop a severe envenomation syndrome characterized by the release of a large amount of cytokines [interleukins (IL) IL-1, IL-6, IL-8], and tumor necrosis factor (TNF). Subsequently, such cytokines produce an acute inflammatory response that triggers adverse effects on skeletal muscles; bone marrow; hepatic and renal functions; and cardiovascular, central nervous, and immune systems. Finally, the aim of the present review is to study historical characteristics and current status of Africanized bees' spread, the composition of their venom, the impact of the bees on the Brazilian economy and ecology, and clinical aspects of their stings including immune response, and to suggest a protocol for bee sting management since there is no safe and effective antivenom available.


Assuntos
Abelhas , Mordeduras e Picadas de Insetos , África , América , Animais , Venenos de Abelha/química , Venenos de Abelha/imunologia , Venenos de Abelha/toxicidade , Abelhas/genética , Abelhas/imunologia , Abelhas/fisiologia , Comportamento Animal , Ecossistema , História do Século XX , Humanos , Hibridização Genética , Mordeduras e Picadas de Insetos/história , Mordeduras e Picadas de Insetos/imunologia , Mordeduras e Picadas de Insetos/terapia , Dinâmica Populacional/história
14.
Neotrop Entomol ; 40(4): 495-500, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21952968

RESUMO

The potential of populations of Bemisia tabaci (Genn.) to become resistant to insecticides has stimulated research into alternative tactics of integrated pest management such as the induction of host-plant resistance. Recent data have shown that silicon can increase the degree of resistance of host plants to insect pests. Therefore the aim of our work was to study the effects of silicon application on the vegetative development of soybean plants and on the induction of resistance to the silverleaf whitefly, B. tabaci biotype B. We performed choice and no-choice tests of oviposition preference on two soybean cultivars, IAC-19 (moderately resistant to B. tabaci biotype B) and MONSOY-8001 (susceptible), with and without application of silicon. Silicon did not affect silverleaf whitefly oviposition preferences, but caused significant mortality in nymphs. Thus, silicon increased the degree of resistance to silverleaf whitefly. Silicon decreased the production of phenolic compounds, but did not affect lignin production. However, when applied to cultivar IAC-19, it increased the production of non-protein organic nitrogen. Silicon had no effect on the vegetative development of soybean plants, but it increased the degree of resistance to the silverleaf whitefly. We conclude that silicon applications combined with cultivar IAC-19 can significantly decrease silverleaf whitefly populations, having a positive impact both on the soybean plant and on the environment.


Assuntos
Resistência à Doença/efeitos dos fármacos , /fisiologia , Hemípteros , Silício/farmacologia , Animais
15.
Braz. j. med. biol. res ; 44(6): 583-591, June 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-589975

RESUMO

Ventilatory differences between rat strains and genders have been described but the morphology of the phrenic nerve has not been investigated in spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats. A descriptive and morphometric study of the phrenic nerves of male (N = 8) and female (N = 9) SHR, and male (N = 5) and female (N = 6) WKY is presented. After arterial pressure and heart rate recordings, the phrenic nerves of 20-week-old animals were prepared for epoxy resin embedding and light microscopy. Morphometric analysis performed with the aid of computer software that took into consideration the fascicle area and diameter, as well as myelinated fiber profile and Schwann cell nucleus number per area. Phrenic nerves were generally larger in males than in females on both strains but larger in WKY compared to SHR for both genders. Myelinated fiber numbers (male SHR = 228 ± 13; female SHR = 258 ± 4; male WKY = 382 ± 23; female WKY = 442 ± 11 for proximal right segments) and density (N/mm²; male SHR = 7048 ± 537; female SHR = 10355 ± 359; male WKY = 9457 ± 1437; female WKY = 14351 ± 1448) for proximal right segments) were significantly larger in females of both groups and remarkably larger in WKY than SHR for both genders. Strain and gender differences in phrenic nerve myelinated fiber number are described for the first time in this experimental model of hypertension, indicating the need for thorough functional studies of this nerve in male and female SHR.


Assuntos
Animais , Feminino , Masculino , Ratos , Nervo Frênico/anatomia & histologia , Ratos Endogâmicos SHR/anatomia & histologia , Ratos Endogâmicos WKY/anatomia & histologia , Bainha de Mielina , Fibras Nervosas Mielinizadas , Fatores Sexuais , Especificidade da Espécie
16.
Actas urol. esp ; 35(6): 325-330, jun. 2011. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-88880

RESUMO

Objetivo: Evaluar los efectos de la rizotomía sacral percutánea por radiofrecuencia en pacientes con lesión de la médula espinal sobre parámetros urodinámicos (capacidad cistométrica máxima [CCM] y presión del detrusor a capacidad cistométrica máxima [PdetCCM]). Material y Métodos: En este estudio prospectivo se evaluó a 8 pacientes con LME (4 hombres y 4 mujeres) con una media de edad de 31,3 años (de 22 a 41). El intervalo medio entre la lesión de la médula espinal y la rizotomía fue de 53,5 meses (entre 20 y 96). A todos los pacientes se les practicó un bloqueo anestésico bajo control fluoroscópico de la tercera raíz sacral de forma bilateral con bupivacaína 0,5%. Se eligió para rizotomía sacral percutánea por radiofrecuencia a los que respondieron con un aumento en la capacidad vesical. Se procedió a la evaluación urodinámica de todos los pacientes a los 6 y los 12 meses tras la realización del procedimiento. Se consignaron tanto la CCM como la PdetCCM. Resultados: Todos los pacientes mostraron una mejora significativa en la CCM a los 12 meses. El volumen vesical medio aumentó de los 100,2±57,1 a 282,9±133,4 ml (p < 0,05). La PdetCCM se redujo de 82,4±31,7 a 69,9±28,7 cm H2O (p = 0,2). Tres pacientes con disreflexia autonómica experimentaron un alivio total de los síntomas tras el procedimiento. A los 12 meses se observó una reaparición de la hiperactividad del detrusor en todos los pacientes. Un paciente presentó abolición de las erecciones reflejas tras el procedimiento. No se observaron complicaciones de importancia en relación con la rizotomía. Conclusiones: La rizotomía sacral percutánea por radiofrecuencia es una técnica mínimamente invasiva, de baja morbilidad, que puede aumentar la CCM. Existe una tendencia hacia la reducción de la PdetCCM en pacientes con LME a los 12 meses, a pesar de que no se alcanza un nivel estadísticamente significativo (AU)


Introduction: To evaluate the effects of percutaneous radiofrequency sacral rhizotomy in spinal cord injured (SCI) patients on urodynamic parameters (maximum cystometric capacity — MCC and detrusor pressure at maximum cystometric capacity - PdetMCC). Material and Methods: This prospective study assessed eight patients with SCI (four men and four women) with a mean age of 31.3 years (22 to 41). Mean interval period between spinal cord lesion and rhizotomy was 53.5 months (20 to 96). All patients underwent an anesthetic block of the 3rd sacral root bilaterally using 0.5% bupivacaine under fluoroscopic control. Those who responded with an increase on bladder capacity were selected to undergo the percutaneous radiofrequency sacral rhizotomy. All patients underwent urodynamic evaluation at 6 and 12months following the procedure. MCC and PdetMCC were recorded. Results: All patients presented a significant improvement on MCC after 12 months. The mean vesical volume increased from 100.2±57.1 to 282.9±133.4 ml (p<0.05). The PdetMCC reduced from 82.4±31.7 to 69.9±28.7 cmH2O (p = 0.2). Three patients with autonomic dysreflexia had complete relief of symptoms after the procedure. At 12 months, recurrence of detrusor hyperactivity was observed in all patients. One patient presented abolishment of reflex erections after the procedure. No major complications related to the rhizotomy were noted.C onclusions: Percutaneous radiofrequency sacral rhizotomy is a minimally invasive technique with low morbidity able to increase MCC. There is a trend towards the reduction of the PdetMCC in SCI patients at 12 months, although statistical significance was not reached (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Traumatismos da Medula Espinal/diagnóstico , Traumatismos da Medula Espinal/cirurgia , Disreflexia Autonômica/diagnóstico , Disreflexia Autonômica/patologia , Bexiga Urinaria Neurogênica/diagnóstico , Incontinência Urinária/diagnóstico , Bexiga Urinaria Neurogênica/complicações , Rizotomia/instrumentação , Rizotomia/métodos , Rizotomia , Urodinâmica , Ablação por Cateter , Anestésicos Locais
17.
Lett Appl Microbiol ; 53(2): 186-92, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21605145

RESUMO

AIMS: The aim of this work was to analyse the coagulant and antibacterial activities of lectin isolated from Moringa oleifera seeds that are used for water treatment. METHODS AND RESULTS: The water-soluble M. oleifera lectin (WSMoL) was separated from nonhemagglutinating components (NHC) by chitin chromatography. WSMoL fluorescence spectrum was not altered in the presence of ions that are often present in high concentrations in polluted waters. Seed extract, NHC and WSMoL showed coagulant activity on a turbid water model. Both NHC and WSMoL reduced the growth of Staphylococcus aureus, but only WSMoL caused a reduction in Escherichia coli. WSMoL was also more effective in reducing the growth of ambient lake water bacteria. CONCLUSIONS: Data obtained from this study indicate that WSMoL is a potential natural biocoagulant for water, reducing turbidity, suspended solids and bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: Moringa oleifera seeds are a material effective in the treatment of water.


Assuntos
Antibacterianos/farmacologia , Lectinas/farmacologia , Moringa oleifera/metabolismo , Sementes/metabolismo , Antibacterianos/metabolismo , Floculação , Lectinas/química , Lectinas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água/química , Purificação da Água/métodos
18.
Braz J Med Biol Res ; 44(6): 583-91, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21537611

RESUMO

Ventilatory differences between rat strains and genders have been described but the morphology of the phrenic nerve has not been investigated in spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats. A descriptive and morphometric study of the phrenic nerves of male (N = 8) and female (N = 9) SHR, and male (N = 5) and female (N = 6) WKY is presented. After arterial pressure and heart rate recordings, the phrenic nerves of 20-week-old animals were prepared for epoxy resin embedding and light microscopy. Morphometric analysis performed with the aid of computer software that took into consideration the fascicle area and diameter, as well as myelinated fiber profile and Schwann cell nucleus number per area. Phrenic nerves were generally larger in males than in females on both strains but larger in WKY compared to SHR for both genders. Myelinated fiber numbers (male SHR = 228 ± 13; female SHR = 258 ± 4; male WKY = 382 ± 23; female WKY = 442 ± 11 for proximal right segments) and density (N/mm²; male SHR = 7048 ± 537; female SHR = 10355 ± 359; male WKY = 9457 ± 1437; female WKY = 14351 ± 1448) for proximal right segments) were significantly larger in females of both groups and remarkably larger in WKY than SHR for both genders. Strain and gender differences in phrenic nerve myelinated fiber number are described for the first time in this experimental model of hypertension, indicating the need for thorough functional studies of this nerve in male and female SHR.


Assuntos
Nervo Frênico/anatomia & histologia , Ratos Endogâmicos SHR/anatomia & histologia , Ratos Endogâmicos WKY/anatomia & histologia , Animais , Feminino , Masculino , Bainha de Mielina , Fibras Nervosas Mielinizadas , Ratos , Fatores Sexuais , Especificidade da Espécie
19.
Actas Urol Esp ; 35(6): 325-30, 2011 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-21477886

RESUMO

INTRODUCTION: To evaluate the effects of percutaneous radiofrequency sacral rhizotomy in spinal cord injured (SCI) patients on urodynamic parameters (maximum cystometric capacity - MCC and detrusor pressure at maximum cystometric capacity - PdetMCC). MATERIAL AND METHODS: This prospective study assessed eight patients with SCI (four men and four women) with a mean age of 31.3years (22 to 41). Mean interval period between spinal cord lesion and rhizotomy was 53.5 months (20 to 96). All patients underwent an anesthetic block of the 3rd sacral root bilaterally using 0.5% bupivacaine under fluoroscopic control. Those who responded with an increase on bladder capacity were selected to undergo the percutaneous radiofrequency sacral rhizotomy. All patients underwent urodynamic evaluation at 6 and 12 months following the procedure. MCC and P(det)MCC were recorded. RESULTS: All patients presented a significant improvement on MCC after 12 months. The mean vesical volume increased from 100.2±57.1 to 282.9±133.4ml (p<0.05). The P(det)MCC reduced from 82.4±31.7 to 69.9±28.7cmH(2)O (p=0.2). Three patients with autonomic dysreflexia had complete relief of symptoms after the procedure. At 12 months, recurrence of detrusor hyperactivity was observed in all patients. One patient presented abolishment of reflex erections after the procedure. No major complications related to the rhizotomy were noted. CONCLUSIONS: Percutaneous radiofrequency sacral rhizotomy is a minimally invasive technique with low morbidity able to increase MCC. There is a trend towards the reduction of the P(det)MCC in SCI patients at 12 months, although statistical significance was not reached.


Assuntos
Ablação por Cateter/métodos , Rizotomia/métodos , Traumatismos da Medula Espinal/complicações , Bexiga Urinaria Neurogênica/cirurgia , Bexiga Urinária Hiperativa/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Bloqueio Nervoso , Tamanho do Órgão , Estudos Prospectivos , Resultado do Tratamento , Bexiga Urinária/patologia , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/patologia , Bexiga Urinária Hiperativa/etiologia , Urodinâmica , Adulto Jovem
20.
J Fish Biol ; 77(6): 1439-45, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21039515

RESUMO

Four substrata were offered to groups of adult Nile tilapia Oreochromis niloticus (one male and two females) simultaneously: pure sand, a mixture of sand and shells, stones and no substratum. The results showed that males chose to dig nests in a lighter and more homogeneous substratum.


Assuntos
Ciclídeos/fisiologia , Ecossistema , Comportamento de Nidação , Animais , Feminino , Masculino
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