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1.
Artigo em Inglês | MEDLINE | ID: mdl-38281705

RESUMO

Superoxide dismutases (SODs) are antioxidant enzymes that protect cells from oxidation. Three SODs have been identified in mammals, but there is limited information in teleosts. This study investigates SODs in the European eel and their expression patterns during testis maturation. Phylogenetic and synteny analyses revealed SODs paralogs and their evolution in vertebrates. The eel possesses one SOD1 and two SOD2/3 (a and b), indicating SOD2 and SOD3 duplication in elopomorphs. SODs expression were then evaluated in various male and female tissues. SOD1 is more expressed in females, while SOD2a and SOD2b dominate brain-pituitary-gonad tissues in both sexes. SOD3a showed predominant expression in the ovary and the male livers, whereas SOD3b was found in the pituitary and brain of both sexes. The effects of different maturation protocols (standard hormonal treatment vs. same protocol preceded with cold seawater pre-treatment) on SODs expression during testis maturation were evaluated. Salinity increase at the onset of standard treatment at 20 °C, simulating early migration, upregulated SOD1, SOD2a, and SOD2b, coinciding with spermatogonia type A differentiated cells dominance. Thereafter, SOD2a and SOD3a decreased, while SOD2b increased during hormonal treatment-induced spermatogenesis. Pre-treatment with seawater at 10 °C, mimicking the conditions at the beginning of the seawater migration, downregulated SOD1 but increased SOD3a expression. Finally, the standard hormonal treatment, replicating spawning at higher temperatures, downregulated SOD1 in eels without any pre-treatment while SOD2a expression increased in pre-treated eels. This study revealed tissue-specific, sex-dependent, and maturation-related SOD expression patterns, predicting SODs dynamic expression profiles during their reproductive migration.


Assuntos
Anguilla , Feminino , Masculino , Animais , Temperatura , Filogenia , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Anguilla/fisiologia , Gônadas , Mamíferos
2.
Ig Sanita Pubbl ; 77(1): 381-403, 2021.
Artigo em Italiano | MEDLINE | ID: mdl-33883749

RESUMO

The Covid-19 pandemic significantly increased the workload for the Italian Health Service. There is few information in the literature on the pediatric population and on the management of pediatric hospitals. The aim of this article is to describe the management of healthcare services during Covid-19 emergency in Regina Margherita Children's Hospital. The Regina Margherita Children's Hospital is specialized in the prevention, diagnosis and treatment of pediatric diseases. About 1000 health worker work in this Hospital and 278 hospitalization places are available.


Assuntos
COVID-19 , Pandemias , Criança , Serviço Hospitalar de Emergência , Hospitais Pediátricos , Humanos , Itália , Saúde Pública , SARS-CoV-2
3.
J Insect Sci ; 17(1)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28130455

RESUMO

Sugarcane is an important crop within the Brazilian socioeconomic landscape. There is a constant need for approaches to increase sustainability at all steps of the production chain. Irrigating sugarcane crops with vinasse is one of these approaches, because vinasse is a residue of sugarcane processing that can be used to fertilize these same crops. However, due to its chemical properties, vinasse may be harmful to soil fauna. Analyzing the structure and functional organization of ant communities is a fast and practical way to monitor sites affected by the addition of chemicals. This study compared the structure of soil ant communities in vinasse-irrigated sugarcane crops to those in secondary forests adjacent to the crops. In total, 32 genera and 107 species of ants were observed; of these, 30 species foraged in crop fields and 102 foraged in forests. Twenty-five percent of the species were present in both crops and forests. Ant communities in crop soil had poorer taxonomic composition and lower richness in each functional group compared to communities in forest remnants. However, regardless of vegetation type, epigeic ants were more diverse, and Dorymyrmex brunneus (crop) and Pachycondyla striata (forest) were very frequent. Vinasse did not increase the diversity of epigeic and hypogeic ants, but it may affect the community composition.


Assuntos
Formigas/fisiologia , Biodiversidade , Fertilizantes/análise , Saccharum/química , Animais , Brasil , Florestas
4.
Pol J Vet Sci ; 20(2): 403-410, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28865226

RESUMO

Food-responsive enteropathy (FRE), idiopathic inflammatory bowel disease (IBD), and alimentary tract lymphoma (AL) are often the remaining differentials for cats presenting with chronic gastrointestinal (GI) signs. Differential diagnosis is further complicated by overlapping clinicopathological features and histopathological changes, however. In this study we describe the clinical presentation of cats with chronic GI signs secondary to FRE, IBD, and AL, and evaluate possible associations between clinical, clinicopathological, ultrasonographic findings and diagnosis. The medical records of client-owned cats with chronic GI signs secondary to FRE, IBD, and AL were reviewed. Univariate and multivariate logistic regression models and receiver-operating characteristic curve (ROC) analysis were used for testing the data. Of the 56 cats included in the study, 22 were diagnosed with FRE (mean age, 70 months ± 49), 17 with IBD (mean age, 101 months ± 40), and 17 with AL (mean age, 122 months ± 45). Cats with FRE were younger and presented more often with diarrhea and less frequently with muscle wasting than cats with IBD or AL. In cats with AL, serum cobalamin levels were lower than in those with FRE or IBD (239 ± 190 ng/L vs. 762 ± 408 ng/L and 625 ± 443 ng/L, respectively) and folate levels were higher than in cats with IBD (18.2 ± 4.2 µg/L vs. 9.1 ± 4.7 µg/L, respectively). Multivariate/ROC curve analysis showed increased values of BUN (sensitivity 100, specificity 29.4, criterion >37 mg/dl) and serum folate (sensitivity 80, specificity 100, criterion >15.6 µg/L) and reduced values of cobalamin (sensitivity 100, specificity 62.5, criterion ≤540 ng/L), which suggested a diagnosis of AL versus IBD. Some clinicopathological features evaluated at diagnosis might suggest AL; however, because differentiating AL from IBD is often difficult, definitive diagnosis should be based on invasive diagnostic workup.


Assuntos
Ração Animal/análise , Doenças do Gato/patologia , Gastroenteropatias/veterinária , Animais , Antígenos , Doenças do Gato/dietoterapia , Gatos , Doença Crônica , Dieta/veterinária , Feminino , Gastroenteropatias/dietoterapia , Gastroenteropatias/patologia , Masculino
5.
Vet Pathol ; 48(4): 814-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21123861

RESUMO

A well-demarcated mass was found by computed tomography in the left cerebellar hemisphere of a 4-year-old male Boxer with acute onset of progressive central vestibular syndrome. At necropsy, the pink, gelatinous mass was in the flocculonodular lobe. Histologically, neoplastic tissue arose from the granular layer of the cerebellar cortex and consisted of sheets of oval to round hyperchromatic cells, consistent with the diagnosis of medulloblastoma. Synaptophysin and neuron-specific enolase immunoreactivity supported the neuronal origin of the neoplastic cells; furthermore, a weak to moderate c-kit expression was detected, as reported in pediatric medulloblastoma. Telomerase activity of tumor cells was demonstrated by immunohistochemistry and by the telomere repeat amplification protocol, suggesting involvement of this enzymatic pathway.


Assuntos
Neoplasias Cerebelares/patologia , Doenças do Cão/patologia , Imuno-Histoquímica/veterinária , Meduloblastoma/veterinária , Telomerase/metabolismo , Animais , Neoplasias Cerebelares/diagnóstico , Doenças do Cão/diagnóstico , Cães , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/fisiologia , Masculino , Meduloblastoma/diagnóstico , Meduloblastoma/patologia
6.
Biochim Biophys Acta Biomembr ; 1863(6): 183584, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33571481

RESUMO

This work investigates how docosahexaenoic acid (DHA) modifies the effect of Cholesterol (Chol) on the structural and dynamical properties of dipalmitoylphosphatidylcholine (DPPC) membrane. We employ low-cost and non-invasive methods: zeta potential (ZP), conductivity, density, and ultrasound velocity, complemented by molecular dynamics simulations. Our studies reveal that 30% of DHA added to the DPPC-Chol system tends to revert Chol action on a model lipid bilayer. Results obtained in this work shed light on the effect of polyunsaturated fatty acids - particularly DHA - on lipid membranes, with potential preventive applications in many diseases, e.g. neuronal as, Alzheimer's disease, and viral, as Covid-19.


Assuntos
Colesterol/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Bicamadas Lipídicas/metabolismo , Fosfatidilcolinas/metabolismo , Lipossomos , Estrutura Molecular , Temperatura , Ondas Ultrassônicas
7.
Chem Phys Lipids ; 231: 104938, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32615121

RESUMO

This work reports the effect of hydroxy-xanthones (XAs) on 1,2-Dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) bilayers as determined by ultrasound velocimetry, densimetry and molecular dynamics simulations. XAs with different number of hydroxyl group were studied. Experimental results, in good agreement with molecular dynamics simulations, revealed that the presence of XAs in the systems studied increases fluidity while simultaneously decreses the compressibility of both membranes. This ´apparent contradiction´ ceases to exist when the particular geometrical structure of the xanthones is taken into account: the planar shape of their fused aromatic rings might allow them to pack efficiently among the hydrocarbon tails of the lipids, thus decreasing compressibility, while their presence weakens or disrupts methylene-methylene interchain interactions, thus increasing membrane fluidity and decreasing their melting temperature.


Assuntos
Bicamadas Lipídicas/química , Fosfatidilcolinas/química , Xantonas/química , Lipossomos/síntese química , Lipossomos/química , Fluidez de Membrana , Simulação de Dinâmica Molecular , Estrutura Molecular
8.
Animal ; 14(6): 1213-1222, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31971122

RESUMO

In teleosts, vitellogenin (Vtg) is a phospholipoglycoprotein synthesized by the liver, released into the blood circulation and incorporated into the oocytes via endocytosis mediated by the Vtg receptor (VTGR) to form the yolk granules. The VTGR is crucial for oocyte growth in egg-laying animals but is also present in non-oviparous vertebrates, such as human. The VTGR belongs to the low-density lipoprotein receptor superfamily (LDLR) and is also named very-low-density lipoprotein receptor (VLDLR). In this study, we identified and phylogenetically positioned the VTGR of a basal teleost, the European eel, Anguilla anguilla. We developed quantitative real-time PCR (qRT-PCR) and investigated the tissue distribution of vtgr transcripts. We compared by qRT-PCR the ovarian expression levels of vtgr in juvenile yellow eels and pre-pubertal silver eels. We also analyzed the regulation of ovarian vtgr expression throughout vitellogenesis in experimentally matured eels. The Vtg plasma level was measured by homologous ELISA experimental maturation. Our in silico search and phylogenetical analysis revealed a single vtgr in the European eel, orthologous to other vertebrate vtgr. The qRT-PCR studies revealed that vtgr is mainly expressed in the ovary and also detected in various other tissues such as brain, pituitary, gill, fat, heart, and testis, suggesting some extra-ovarian functions of VTGR. We showed that vtgr is expressed in ovaries of juvenile yellow eels with no higher expression in pre-pubertal silver eels nor in experimentally matured eels. This suggests that vtgr transcription already occurs during early pre-vitellogenesis of immature eels and is not further activated in vitellogenic oocytes. European eel Vtg plasma level increased throughout experimental maturation in agreement with previous studies. Taken together, these results suggest that vtgr transcript levels may not be a limiting step for the uptake of Vtg by the oocyte in the European eel.


Assuntos
Anguilla/fisiologia , Proteínas do Ovo/metabolismo , Receptores de Superfície Celular/metabolismo , Vitelogênese/fisiologia , Vitelogeninas/metabolismo , Animais , Proteínas do Ovo/genética , Feminino , Regulação da Expressão Gênica/fisiologia , Fígado/metabolismo , Oócitos/metabolismo , Ovário/metabolismo , Hipófise , Receptores de Superfície Celular/genética , Receptores de LDL , Maturidade Sexual
9.
J Nonlinear Sci ; 28(2): 513-542, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527100

RESUMO

We investigate the influence of periodic surface roughness in thin ferromagnetic films on shape anisotropy and magnetization behavior inside the ferromagnet. Starting from the full micromagnetic energy and using methods of homogenization and [Formula: see text]-convergence, we derive a two-dimensional local reduced model. Investigation of this model provides an insight into the formation mechanism of perpendicular magnetic anisotropy and uniaxial anisotropy with an arbitrary preferred direction of magnetization.

10.
Chem Phys Lipids ; 217: 12-18, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30359585

RESUMO

Docosahexaenoic acid (DHA, 22:6) is a natural active compound that has raised considerable interest due to its several biological effects. In this work, effects of free DHA on the physicochemical properties of dipalmitoylphosphatidylcholine (DPPC) liposomes are investigated in terms of lipid membrane structure, by means of temperature-dependent zeta potential measurements, density studies and molecular dynamics simulations. Experimental results predict, in good agreement with simulations that DHA readily incorporates into DPPC liposomes, localizing at the lipid headgroup region. These data show that DHA induces changes in the lipid bilayer structure as well as in membrane fluidity.


Assuntos
Ácidos Docosa-Hexaenoicos/química , Lipossomos/química , 1,2-Dipalmitoilfosfatidilcolina/química , Bicamadas Lipídicas/química , Fluidez de Membrana , Simulação de Dinâmica Molecular , Temperatura de Transição , Água/química
11.
J Colloid Interface Sci ; 314(2): 699-706, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17658541

RESUMO

The aqueous mixed system decyltrimethylammonium bromide (C(10)TAB)-hexadecyltrimethylammonium bromide (C(16)TAB) was studied by conductivity, ion-selective electrodes, surface tension, and fluorescence spectroscopy techniques. The mixture critical micelle concentration, cmc(*), aggregation number, N( *), and micelle molar conductivity, Lambda(M)(cmc), showed that the system aggregation is strongly nonideal. Both cmc(*) and N( *) results were analyzed with two different procedures: (i) the regular solution theory on mixed micelles or Rubingh's theory, and (ii) by the determination of the partial critical micelle concentration of the amphiphile component i in the presence of a constant concentration of the other amphiphile component, cmc(i)( *). The Rubingh procedure gives micelles richer in C(16)TAB than the overall mixtures, while procedure (ii) gives micelles having the same composition as in the complete surfactant mixture (alpha(C(10)TAB). Mixed micelles are larger than pure surfactant ones, with nonspherical shape. Using a literature model, the cause of the synergistic effect seems to be a reduction of the hydrocarbon/water contact at the micelle surface when mixed micelles form. Conductivity and ion-selective electrodes indicate that highly ionized premicelles form immediately before the cmc(*). The air/solution interface is strongly nonideal and much richer in C(16)TAB than the composition in the bulk. When micelles form there is a strong desorption from the air/solution interface because micelles are energetically favored when compared with the monolayer.

12.
Braz J Biol ; 67(4): 635-41, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18278314

RESUMO

The relationships between an urban ecosystem located near the Atlantic Rainforest in southeastern Brazil and ant communities were studied with the objective of quantifying the ant richness and abundance in the household environment and its surroundings. Eighty residences were sampled, where 58 species and 28 genera pertaining to 7 sub-families were found to be present. Inside the residences, the species richness was found to be lower (26), although the abundance was greater (10,670), with the wash area and kitchen being the locales that contributed with the greatest number of hits. The opposite was true in the areas outside the residences, where 54 species and 3,747 ants were observed. Inside houses, the species known as Tramp ants were found, in the following order of importance: Solenopsis saevissima, Tapinoma melanocephalum, Linepithema humile, Paratrechina fulva, Wasmannia auropunctata, P. longicornis, Pheidole megacephala, Monomorium pharaonis and M. floricola. Externally, mainly in the yards and gardens, species such as Octostruma rugifera, Heteroponera dolo, Hypoponera sp.1 and sp.6, Gnamptogenys sp. 4, G. striatula, Odontomachus meinerti, Pachycondyla constricta and P. striata were found. In general, a greater number of species and lower abundance of individuals were observed in the neighborhoods nearer the mountains than in those closer to the urban center.


Assuntos
Formigas/classificação , Ecossistema , Animais , Biodiversidade , Brasil , Densidade Demográfica
13.
Chem Phys Lipids ; 206: 1-8, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28533145

RESUMO

Xanthones and derivatives are natural active compounds whose interest has been increased due to its several pharmacological effects. In this work, effects of hydroxy-xanthones on the physicochemical properties of dipalmitoylphosphatidylcholine (DPPC) liposomes have been investigated in terms of lipid bilayer fluidity, by means of molecular dynamics simulations and temperature dependence of zeta potential studies. Experimental results predict, in good agreement with simulations, that xanthones are able to be incorporated into DPPC liposomes with certain localization, fluidizing the bilayer. Both effects, localization and fluidity were found to be dependent of the number of hydroxilic substituents of the xanthone and the lipid phase state.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Bicamadas Lipídicas/química , Simulação de Dinâmica Molecular , Xantonas/química , Xantonas/farmacologia , Fenômenos Químicos/efeitos dos fármacos , Temperatura
14.
J Econ Entomol ; 110(1): 111-117, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28053209

RESUMO

In many sugarcane plantations in Brazil, the straw is left on the soil after harvesting, and vinasse, a by-product of the production of sugar and ethanol, is used for fertigation. Our goal was to compare ant community composition and species richness in the straw mulch of sugarcane crops with the leaf litter of neighboring forests. We tested the hypothesis that ant communities in the straw mulch of vinasse-irrigated sugarcane crops and in the forest leaf litter were similar, because the combination of straw mulching and vinasse irrigation has a positive effect on soil fauna. Straw mulch and leaf litter were collected from 21 sites and placed in Berlese funnels. In total, 61 species were found in the forest leaf litter, whereas 34 and 28 species were found in the straw mulch of sugarcane fields with and without vinasse, respectively. Ant communities differed between forest and crop fields, but the species in the sugarcane straw mulch were a subset of the species found in the forest leaf litter. Although vinasse is rich in organic matter, it did not increase ant diversity. Seven feeding and/or foraging types were identified and, among the different types, surface-foraging omnivorous ants were the most prevalent in all habitats. Vinasse-irrigated sugarcane straw mulch had more predatory species than mulch from vinasse-free fields, but fewer than forest leaf litter. However, this positive effect of vinasse irrigation should be carefully evaluated because vinasse has negative effects on the environment.


Assuntos
Formigas/fisiologia , Biodiversidade , Florestas , Saccharum , Solo , Animais , Brasil , Folhas de Planta , Saccharum/crescimento & desenvolvimento
15.
Vet J ; 223: 73-75, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28671077

RESUMO

There is little information on sequence variation of canine adenovirus type 1 (CAdV-1), the aetiological agent of infectious canine hepatitis (ICH). This study reports hexon and fibre gene sequence variants of CAdV-1 in a dog with systemic ICH and a dog with the ocular form of the disease ('blue eye') in Northern Italy in 2013. One of the sequence variants matched a CAdV-1 fox sequence previously detected in Italy.


Assuntos
Infecções por Adenoviridae/veterinária , Adenovirus Caninos/genética , Proteínas do Capsídeo/genética , Oftalmopatias/veterinária , Variação Genética/genética , Hepatite Infecciosa Canina/virologia , Infecções por Adenoviridae/virologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas do Capsídeo/química , Cães , Oftalmopatias/virologia , Itália , Masculino
16.
J Phys Chem B ; 110(35): 17600-6, 2006 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16942105

RESUMO

The mixed surfactant system sodium 10-undecenoate (SUD)-dodecyltrimethylammonium bromide (DTAB) was studied by computational simulation to determine the composition and structure of the mixed microstructures. Results were contrasted with experimental data obtained from literature and our own laboratory. The modelization predicts spherical or cylindrical micelles with a preferential composition of SUD-DTAB of about 1:2, while the system predicts a lamellar structure with a proportion of 1:1 when SUD is replaced by the saturated soap sodium undecanoate. The model also predicts the deep inclusion of bromide ions in the micelle Stern layer. All predictions were in agreement with previous experimental results.

17.
Cancer Res ; 61(22): 8171-8, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11719447

RESUMO

The thiol N-acetyl-L-cysteine (NAC), an analogue and precursor of reduced glutathione, has cancer chemopreventive properties attributable to its nucleophilicity, antioxidant activity, and a variety of other mechanisms. We demonstrated recently that NAC has anti-invasive, antimetastatic, and antiangiogenic effects in in vitro and in vivo test systems. In the present study, s.c. transplantation of KS-Imm cells in (CD-1)BR nude mice resulted in the local growth of Kaposi's sarcoma, a highly vascularized human tumor. The daily administration of NAC with drinking water, initiated after the tumor mass had become established and detectable, produced a sharp inhibition of tumor growth, with regression of tumors in half of the treated mice along with a markedly prolonged median survival time. The production of vascular endothelial growth factor (VEGF) and certain proliferation markers (proliferating cell nuclear antigen and Ki-67) were significantly lower in Kaposi's sarcomas from NAC-treated mice than from control mice. Treatment of KS-Imm cells with NAC in vitro resulted in a dose-dependent inhibition of chemotaxis and invasion through inhibition of gelatinase-A (matrix metalloproteinase-2, MMP-2) activity without altering MMP-2 or MMP-9 mRNA levels. NAC also significantly inhibited VEGF production but did not affect proliferation markers in vitro. Reverse transcription-PCR analysis indicated that total VEGF mRNAs were reduced by 10 mM NAC. Taken together, these findings provide evidence that NAC, the safety of which even at high doses has been established in almost 40 years of clinical use, in addition to its chemopreventive action, has a strong antiangiogenic potential that could be exploited for preventing cancer progression as well as used in cancer adjuvant therapy.


Assuntos
Acetilcisteína/farmacologia , Inibidores da Angiogênese/farmacologia , Neovascularização Patológica/tratamento farmacológico , Sarcoma de Kaposi/irrigação sanguínea , Administração Oral , Animais , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Movimento Celular/efeitos dos fármacos , Fatores de Crescimento Endotelial/antagonistas & inibidores , Fatores de Crescimento Endotelial/biossíntese , Fatores de Crescimento Endotelial/genética , Feminino , Inibidores do Crescimento/farmacologia , Humanos , Antígeno Ki-67/metabolismo , Linfocinas/antagonistas & inibidores , Linfocinas/biossíntese , Linfocinas/genética , Masculino , Camundongos , Camundongos Nus , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Sarcoma de Kaposi/patologia , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Cancer Res ; 61(14): 5441-6, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11454689

RESUMO

Gene transfer delivery of endogenous angiogenesis inhibitors such as angiostatin would circumvent problems associated with long-term administration of proteins. Kaposi's sarcoma (KS), a highly vascular neoplasm, is an excellent model for studying tumor angiogenesis and antiangiogenic agent efficacy. We investigated the effects of angiostatin gene transfer in in vitro and in vivo models of KS-induced neovascularization and tumor growth. A eukaryotic expression plasmid and a Moloney leukemia virus-based retroviral vector for expression of murine angiostatin were generated harboring the angiostatin cDNA with cleavable leader signals under the control of either the strong cytomegalovirus promoter/enhancer or the Moloney leukemia virus long terminal repeat. Angiostatin secretion was confirmed by radioimmunoprecipitation and Western blot analysis. Supernatants of angiostatin-transfected cells inhibited endothelial cell migration in vitro. Stable gene transfer of the angiostatin cDNA by retroviral vectors in KS-IMM cells resulted in sustained angiostatin expression and delayed tumor growth in nude mice, which was associated with reduced vascularization. These findings suggest that gene therapy with angiostatin might be useful for treatment of KS and possibly other highly angiogenic tumors.


Assuntos
Fragmentos de Peptídeos/fisiologia , Plasminogênio/fisiologia , Sarcoma de Kaposi/patologia , Angiostatinas , Animais , Divisão Celular , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Quimiotaxia/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Vetores Genéticos/genética , Humanos , Camundongos , Fragmentos de Peptídeos/genética , Plasminogênio/genética , Sarcoma de Kaposi/genética , Transfecção , Células Tumorais Cultivadas
19.
Colloids Surf B Biointerfaces ; 142: 199-206, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26954086

RESUMO

Temperature dependence of the zeta potential (ZP) is proposed as a tool to analyze the thermotropic behavior of unilamellar liposomes prepared from binary mixtures of phosphatidylcholines in the absence or presence of ions in aqueous suspensions. Since the lipid phase transition influences the surface potential of the liposome reflecting a sharp change in the ZP during the transition, it is proposed as a screening method for transition temperatures in complex systems, given its high sensitivity and small amount of sample required, that is, 70% less than that required in the use of conventional calorimeters. The sensitivity is also reflected in the pre-transition detection in the presence of ions. Plots of phase boundaries for these mixed-lipid vesicles were constructed by plotting the delimiting temperatures of both main phase transition and pre-transition vs. the lipid composition of the vesicle. Differential scanning calorimetry (DSC) studies, although subject to uncertainties in interpretation due to broad bands in lipid mixtures, allowed the validation of the temperature dependence of the ZP method for determining the phase transition and pre-transition temperatures. The system chosen was dipalmitoylphosphatidylcholine/dimyristoyl phosphatidylcholine (DMPC/DPPC), the most common combination in biological membranes. This work may be considered as a starting point for further research into more complex lipid mixtures with functional biological importance.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Dimiristoilfosfatidilcolina/química , Transição de Fase , Lipossomas Unilamelares/química , Água/química , Varredura Diferencial de Calorimetria , Técnicas Eletroquímicas , Soluções , Eletricidade Estática , Temperatura
20.
Zoonoses Public Health ; 63(7): 569-576, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26952244

RESUMO

This study was conducted to estimate the prevalence of Salmonella spp. and their antimicrobial susceptibilities on poultry and swine farms, sampled in 2 regions in Central Vietnam. A total of 67 poultry farms and 46 swine farms were sampled in a period of 5 months (from September 2012 to January 2013). Salmonella spp. was prevalent in 46.3% and 71.7% of poultry and swine farms, respectively. Altogether, 99 non-typhoidal Salmonella were isolated and the most common serovars were Salmonella Weltevreden (19%), followed by Salmonella Typhimurium (12%) and Salmonella 4,[5],12:i:- (11%). Overall, 71 of 99 (72%) Salmonella isolates were resistant to at least one of the 14 antimicrobial agents tested. Both in poultry and swine farms, high levels of resistance were observed for ampicillin, chloramphenicol, ciprofloxacin, sulphamethoxazole and tetracycline. The presence of Salmonella isolates from poultry and swine farms which were resistant to different classes of antimicrobials suggests that alternative control measures to antimicrobials should be implemented. Moreover, an effective policy should be promoted to encourage a prudent use of these agents in animal farming in Vietnam.


Assuntos
Antibacterianos/farmacologia , Galinhas , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella/classificação , Doenças dos Suínos/microbiologia , Animais , Farmacorresistência Bacteriana , Abrigo para Animais , Doenças das Aves Domésticas/epidemiologia , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Salmonelose Animal/epidemiologia , Suínos , Doenças dos Suínos/epidemiologia , Vietnã
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