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1.
Rev. Soc. Bras. Med. Trop ; 52: e20180300, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1041561

RESUMO

Abstract INTRODUCTION The nematode Caenorhabditis elegans was used as a biological sensor to detect the urine of sepsis patients (CESDA assay). METHODS C. elegans was aliquoted onto the center of assay plates and allowed to migrate towards sepsis (T) or control (C) urine samples spotted on the same plate. The number of worms found in either (T) or (C) was scored at 10-minute intervals over a 60-minute period. RESULTS The worms were able to identify the urine (<48 hours) of sepsis patients rapidly within 20 minutes (AUROC=0.67, p=0.012) and infection within 40 minutes (AUROC=0.80, p=0.016). CONCLUSIONS CESDA could be further explored for sepsis diagnosis.


Assuntos
Humanos , Animais , Biomarcadores/urina , Quimiotaxia , Caenorhabditis elegans , Sepse/diagnóstico , Fatores de Tempo , Sensibilidade e Especificidade , Sepse/urina
2.
Biol. Res ; 51: 12, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-950898

RESUMO

BACKGROUND: Chemokine (C-C motif) receptor 6 (CCR6) is present in sperm and plays a significant role in sperm motility and chemotaxis acting in the reproductive tracts. However, the expression and functional significance of CCR6 in testis are still poorly understood, especially in the process of spermatogenesis. METHODS AND RESULTS: CCR6 was expressed in spermatogenic cell lines and its expression was shown in an age-dependent upregulation manner from puberty to adulthood in mouse testis. Immunostaining results confirmed the localization of CCR 6 in testis. Further chemotaxis assays demonstrated that spermatogenic cells GC-1 and -2 exhibited a directional movement toward CCR6-specific ligand such as CCL20 or Sertoli cells in vitro. CONCLUSIONS: The present findings indicate that CCR6 is involved in the chemotaxis of spermatogenic cells in vitro and promotes chemotaxis under non-inflammatory conditions during normal spermatogenesis.


Assuntos
Humanos , Animais , Masculino , Camundongos , Coelhos , Espermatogênese/fisiologia , Quimiotaxia/fisiologia , Criptorquidismo/metabolismo , Quimiocina CCL20/metabolismo , Receptores CCR6/metabolismo , Células de Sertoli , Motilidade dos Espermatozoides/fisiologia , Testículo/fisiologia , Imuno-Histoquímica , Western Blotting , Imunofluorescência , Camundongos Endogâmicos C57BL
3.
Braz. j. biol ; 77(2): 340-346, Apr.-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888739

RESUMO

Abstract Biomphalaria amazonica is a planorbid species considered a potential host of Schistosoma mansoni. It is widely distributed in the Neotropical zone, particularly in the North and Centre-West of Brazil and in the North of Bolivia. The aim of the present study was to determine the host-parasite relationship between B. amazonica and S. mansoni (BH and SJ strains). Specimens of B. amazonica and their snail-conditioned water were examined in terms of their ability to attract miracidia. The infectivity of the mollusks was determined by exposing them to 20 miracidia of both strains. Sporocyst development and amebocyte reactions were studied after each mollusk specimen was exposed to 100 miracidia. Although no cercariae were eliminated, specimens of B. amazonica proved capable of attracting 77% of the miracidia they were exposed to. Viable sporocysts with no amebocyte reaction were found 96 hours after the exposure to miracidia. These results indicate the susceptibility of B. amazonica to the BH and SJ strains of S. mansoni, and therefore demonstrate the importance of this planorbid species as a potential vector of the trematode in the areas where it occurs.


Resumo Biomphalaria amazonica é uma espécie de planorbídeo considerada vetora potencial do Schistosoma mansoni. É amplamente distribuída na zona neotropical, especialmente no Norte e Centro-Oeste do Brasil e Norte da Bolívia. O presente trabalho teve por objetivo estudar a relação parasito-hospedeiro entre B. amazonica e S. mansoni (linhagens BH e SJ). Espécimes de B. amazonica e sua água de condicionamento foram examinados em relação à sua capacidade de atração miraxonal. A infectividade dos moluscos foi testada expondo-os a 20 miracídios de ambas as linhagens. A viabilidade dos esporocistos e o desenvolvimento de reações amebocitárias foram estudados após cada molusco ser exposto a 100 miracídios. Apesar de não eliminarem cercárias, B. amazonica provou ser capaz de atrair 77% dos miracídios a que foram expostos. Esporocistos viáveis sem reação amebócitaria foram encontrados 96 horas após a exposição aos miracídios. Esses resultados indicam a suscetibilidade de B. amazonica às linhagens BH e SJ de S. mansoni e, portanto, demonstram a importância desta espécie de planorbídeo como um vetor potencial do trematodeo na área onde ele ocorre.


Assuntos
Animais , Schistosoma mansoni/fisiologia , Biomphalaria/parasitologia , Interações Hospedeiro-Parasita , Schistosoma mansoni/crescimento & desenvolvimento , Brasil , Quimiotaxia , Oocistos/crescimento & desenvolvimento , Oocistos/fisiologia , Cercárias/crescimento & desenvolvimento , Cercárias/fisiologia
4.
Arch. endocrinol. metab. (Online) ; 59(3): 245-251, 06/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-751309

RESUMO

Objective Evaluate the effect of glycemic index (GI) on biochemical parameters, food intake, energy metabolism, anthropometric measures and body composition in overweight subjects.Materials and methods Simple blind study, in which nineteen subjects were randomly assigned to consume in the laboratory two daily low GI (n = 10) or high GI (n = 9) meals, for forty-five consecutive days. Habitual food intake was assessed at baseline. Food intake, anthropometric measures and body composition were assessed at each 15 days. Energy metabolism and biochemical parameters were evaluated at baseline and the end of the study.Results Low GI meals increased fat oxidation, and reduced waist circumference and HOMA-IR, while high GI meals increased daily dietary fiber and energy intake compared to baseline. There was a higher reduction on waist circumference and body fat, and a higher increase on postprandial fat oxidation in response to the LGI meals than after high GI meals. High GI meals increased fasting respiratory coefficient compared to baseline and low GI meals.Conclusion The results of the present study showed that the consumption of two daily low GI meals for forty-five consecutive days has a positive effect on obesity control, whereas, the consumption of high GI meals result has the opposite effect. Arch Endocrinol Metab. 2015;59(3):245-51.


Assuntos
Proteínas de Bactérias/química , Escherichia coli/enzimologia , Proteínas de Membrana/química , Fenilalanina/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Quimiotaxia , Sequência Conservada , Dimerização , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/fisiologia , Dados de Sequência Molecular , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Conformação Proteica , Fenilalanina/genética , Fenilalanina/metabolismo
5.
Dental press j. orthod. (Impr.) ; 20(2): 16-19, Mar-Apr/2015. graf
Artigo em Inglês | LILACS | ID: lil-745862

RESUMO

Deciduous teeth exfoliate as a result of apoptosis induced by cementoblasts, a process that reveals the mineralized portion of the root while attracting clasts. Root resorption in deciduous teeth is slow due to lack of mediators necessary to speed it up; however, it accelerates and spreads in one single direction whenever a permanent tooth pericoronal follicle, rich in epithelial growth factor (EGF), or other bone resorption mediators come near. The latter are responsible for bone resorption during eruption, and deciduous teeth root resorption and exfoliation. Should deciduous teeth be subjected to orthodontic movement or anchorage, mediators local levels will increase. Thus, one should be fully aware that root resorption in deciduous teeth will speed up and exfoliation will early occur. Treatment planning involving deciduous teeth orthodontic movement and/or anchorage should consider: Are clinical benefits relevant enough as to be worth the risk of undergoing early inconvenient root resorption?.


O dente decíduo é esfoliado graças à apoptose em seus cementoblastos, que desnuda a parte mineralizada da raiz e atrai os clastos. A rizólise é lenta, pois faltam mediadores em quantidade para acelerar o processo, mas ela se acelera e unidireciona quando se aproxima um folículo pericoronário de dente permanente rico em EGF e outros mediadores da reabsorção óssea - os responsáveis pelas reabsorções óssea na erupção e dentária decídua na rizólise e esfoliação. Se houver movimentação ortodôntica ou ancoragem em dentes decíduos, aumenta-se, também, o nível local desses mesmos mediadores, devendo-se estar bem consciente de que haverá uma aceleração da rizólise e, em decorrência, uma antecipação de sua esfoliação. No planejamento de casos em que dentes decíduos estejam envolvidos na movimentação ortodôntica e/ou ancoragem, deve-se ponderar: o benefício clínico para o paciente será relevante, a ponto de valer o risco de uma rizólise abreviada e inconveniente?.


Assuntos
Humanos , Dente Decíduo/fisiologia , Técnicas de Movimentação Dentária/métodos , Reabsorção da Raiz/fisiopatologia , Erupção Dentária/fisiologia , Esfoliação de Dente/fisiopatologia , Reabsorção Óssea/fisiopatologia , Quimiotaxia/fisiologia , Apoptose/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Cemento Dentário/fisiologia , Saco Dentário/citologia , Saco Dentário/fisiologia , Fator de Crescimento Epidérmico/fisiologia , Células Epiteliais/fisiologia , Procedimentos de Ancoragem Ortodôntica/métodos , Odontoblastos/fisiologia
6.
Braz. j. med. biol. res ; 48(2): 161-166, 02/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-735848

RESUMO

Our aim was to investigate the role of chemokines in promoting instability of coronary atherosclerotic plaques and the underlying molecular mechanism. Coronary angiography and intravascular ultrasound (IVUS) were performed in 60 stable angina pectoris (SAP) patients and 60 unstable angina pectoris (UAP) patients. The chemotactic activity of monocytes in the 2 groups of patients was examined in Transwell chambers. High-sensitivity C-reactive protein (hs-CRP), monocyte chemoattractant protein-1 (MCP-1), regulated on activation in normal T-cell expressed and secreted (RANTES), and fractalkine in serum were examined with ELISA kits, and expression of MCP-1, RANTES, and fractalkine mRNA was examined with real-time PCR. In the SAP group, 92 plaques were detected with IVUS. In the UAP group, 96 plaques were detected with IVUS. The plaques in the UAP group were mainly lipid 51.04% (49/96) and the plaques in the SAP group were mainly fibrous 52.17% (48/92). Compared with the SAP group, the plaque burden and vascular remodeling index in the UAP group were significantly greater than in the SAP group (P<0.01). Chemotactic activity and the number of mobile monocytes in the UAP group were significantly greater than in the SAP group (P<0.01). Concentrations of hs-CRP, MCP-1, RANTES, and fractalkine in the serum of the UAP group were significantly higher than in the serum of the SAP group (P<0.05 or P<0.01), and expression of MCP-1, RANTES, and fractalkine mRNA was significantly higher than in the SAP group (P<0.05). MCP-1, RANTES, and fractalkine probably promote instability of coronary atherosclerotic plaque.


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Angina Pectoris/metabolismo , Quimiocinas/metabolismo , Quimiotaxia/fisiologia , Doença da Artéria Coronariana/metabolismo , Monócitos/metabolismo , Placa Aterosclerótica/fisiopatologia , Angina Pectoris/fisiopatologia , Proteína C-Reativa/análise , /sangue , /sangue , /sangue , Doença da Artéria Coronariana/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real , Ultrassonografia de Intervenção
7.
J. venom. anim. toxins incl. trop. dis ; 21: 25, 31/03/2015. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954750

RESUMO

Background The skin secretions of toads of the family Bufonidae contain biogenic amines, alkaloids, steroids (bufotoxins), bufodienolides (bufogenin), peptides and proteins. The poison of Rhinella schneideri, formerly classified as Bufo paracnemis, presents components that act on different biological systems, including the complement system. The aim of this study was to isolate and examine the activity ofRhinella schneideri poison (RsP) components on the complement system.Methods The components active on the complement system were purified in three chromatographic steps, using a combination of cation-exchange, anion-exchange and gel filtration chromatography. The resulting fractions were analyzed by SDS-PAGE and screened for their activity in the hemolytic assay of the classical/lectin complement pathways. Fractions active on the complement system were also assessed for their ability to generate C3 fragments evaluated by two dimensional immunoelectrophoresis assay, C3a and C5a by neutrophil chemotaxis assay and SC5b-9 complex by ELISA assay.Results The fractionation protocol was able to isolate the component S5 from theRsP, as demonstrated by SDS-PAGE and the RP-FPLC profile. S5 is a protein of about 6000 Da, while S2 presents components of higher molecular mass (40,000 to 50,000 Da). Fractions S2 and S5 attenuated the hemolytic activity of the classical/lectin pathways after preincubation with normal human serum. Both components stimulated complement-dependent neutrophil chemotaxis and the production of C3 fragments, as shown by two-dimensional immunoelectrophoresis. S2 showed a higher capacity to generate the SC5b- 9 complex than the other fractions. This action was observed after the exposure of normal human serum to the fractions.Conclusions This is the first study to examine the activity of RsP components on the complement system. Fractions S2 and S5 reduced the complement hemolytic activity, stimulated complement-dependent neutrophil chemotaxis and stimulated the production of C3 fragments, indicating that they were able to activate the complement cascade. Furthermore, fraction S2 was also able to generate the SC5b-9 complex. These components may be useful tools for studying dysfunction of the complement cascade.(AU)


Assuntos
Animais , Venenos , Produtos Biológicos , Bufonidae , Quimiotaxia
8.
J. venom. anim. toxins incl. trop. dis ; 21: 29, 31/03/2015. ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954745

RESUMO

Background Activation of the complement system plays an important role in the regulation of immune and inflammatory reactions, and contributes to inflammatory responses triggered by envenomation provoked byBothrops snakes. The present study aimed to assess whether Bothrops jararacussuand Bothrops pirajai crude venoms and their isolated toxins, namely serine protease (BjussuSP-I) and L-amino acid oxidase (BpirLAAO-I), modulate human complement system pathways.Methods Lyophilized venom and toxin samples solubilized in phosphate buffered saline were diluted in appropriate buffers to evaluate their hemolytic activity on the alternative and classical pathways of the complement system. Venom- and toxin-treated normal human serum was added to the erythrocyte suspension, and the kinetic of hemolysis was measured spectrophotometrically at 700 nm. The kinetic 96-well microassay format was used for this purpose. We determined the t ½values (time required to lyse 50 % of target erythrocytes), which were employed to calculate the percentage of inhibition of the hemolytic activity promoted by each sample concentration. To confirm complement system activation, complement-dependent human neutrophil migration was examined using the Boyden chamber model.Results At the highest concentration tested (120 μg/mL), B. jararacussu and B. pirajai crude venoms inhibited the hemolytic activity of the classical pathway (65.3 % and 72.4 %, respectively) more strongly than they suppressed the hemolytic activity of the alternative pathway (14.2 and 13.6 %, respectively). BjussuSP-I (20 μg/mL) did not affect the hemolytic activity of the classical pathway, but slightly decreased the hemolytic activity of the alternative pathway (13.4 %). BpirLAAO-I (50 μg/mL) inhibited 24.3 and 12.4 % of the hemolytic activity of the classical and alternative pathways, respectively. Normal human serum treated with B. jararacussu and B. pirajai crude venoms induced human neutrophil migration at a level similar to that induced by zymosan-activated normal human serum.Conclusion Together, the results of the kinetics of hemolysis and the neutrophil chemotaxis assay suggest that pre-activation of the complement system byB. jararacussu and B. pirajai crude venoms consumes complement components and generates the chemotactic factors C3a and C5a. The kinetic microassay described herein is useful to assess the effect of venoms and toxins on the hemolytic activity of the complement system.(AU)


Assuntos
Animais , Venenos de Serpentes , Serpentes , Quimiotaxia , Serina Proteases
9.
Biol. Res ; 47: 1-9, 2014. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-950754

RESUMO

Diabetic retinopathy is one of the most important causes of blindness. The underlying mechanisms of this disease include inflammatory changes and remodeling processes of the extracellular-matrix (ECM) leading to pericyte and vascular endothelial cell damage that affects the retinal circulation. In turn, this causes hypoxia leading to release of vascular endothelial growth factor (VEGF) to induce the angiogenesis process. Alpha-1 antitrypsin (AAT) is the most important circulating inhibitor of serine proteases (SERPIN). Its targets include elastase, plasmin, thrombin, trypsin, chymotrypsin, proteinase 3 (PR-3) and plasminogen activator (PAI). AAT modulates the effect of protease-activated receptors (PARs) during inflammatory responses. Plasma levels of AAT can increase 4-fold during acute inflammation then is so-called acute phase protein (APPs). Individuals with low serum levels of AAT could develop disease in lung, liver and pancreas. AAT is involved in extracellular matrix remodeling and inflammation, particularly migration and chemotaxis of neutrophils. It can also suppress nitric oxide (NO) by nitric oxide sintase (NOS) inhibition. AAT binds their targets in an irreversible way resulting in product degradation. The aim of this review is to focus on the points of contact between multiple factors involved in diabetic retinopathy and AAT resembling pleiotropic effects that might be beneficial.


Assuntos
Humanos , Animais , Inibidores de Serino Proteinase/uso terapêutico , alfa 1-Antitripsina/uso terapêutico , Retinopatia Diabética/tratamento farmacológico , Hipóxia Celular , Inibidores de Serino Proteinase/metabolismo , Movimento Celular/fisiologia , Quimiotaxia/fisiologia , alfa 1-Antitripsina/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Mediadores da Inflamação/antagonistas & inibidores , Óxido Nítrico Sintase/antagonistas & inibidores , Substâncias Protetoras/metabolismo , Receptores Ativados por Proteinase/metabolismo , Retinopatia Diabética/fisiopatologia , Radicais Livres , Inflamação/metabolismo , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/uso terapêutico , Neutrófilos/fisiologia
11.
Rev. argent. microbiol ; 43(2): 107-110, jun. 2011. ilus, graf
Artigo em Inglês | LILACS | ID: lil-634680

RESUMO

In this study, two halophilic bacterial strains isolated from saline habitats in Argentina grew in the presence of gas oil. They were identified as Halomonas spp. and Nesterenkonia sp. by 16S ribosomal RNA sequencing. Chemotaxis towards gas oil was observed in Halomonas spp. by using swimming assays.


En el presente trabajo se aislaron dos cepas bacterianas halofílicas a partir de muestras obtenidas en ambientes salinos de Argentina, que crecieron en presencia de gasoil como única fuente de carbono. Las cepas aisladas se identificaron como Halomonas spp. y Nesterenkonia sp. mediante secuenciación del gen del ARN ribosomal 16S. En ensayos de swimming, las cepas del genero Halomonas spp. mostraron una respuesta quimiotáctica hacia el gas oil.


Assuntos
Quimiotaxia/efeitos dos fármacos , Halomonas/efeitos dos fármacos , Micrococcaceae/efeitos dos fármacos , Petróleo , Argentina , Biodegradação Ambiental , Hidrocarbonetos , Halomonas/crescimento & desenvolvimento , Halomonas/isolamento & purificação , Micrococcaceae/crescimento & desenvolvimento , Micrococcaceae/isolamento & purificação , Ribotipagem , Tolerância ao Sal , Especificidade da Espécie , Água do Mar/microbiologia , Microbiologia da Água , Poluentes Químicos da Água
12.
Mem. Inst. Oswaldo Cruz ; 106(4): 461-466, June 2011. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-592190

RESUMO

Chagas disease is a major public health issue and is mainly spread by Triatominae insects (Hemiptera: Reduviidae). Rhodnius prolixus is the main vector species in Northern South America. Host-seeking behaviour in R. prolixus is mediated by different compounds that are produced by and emanate from the host or microbiota on the host's skin. We tested the behavioural responses of sylvatic first filial generation (F1) and colony insects to extracts of human skin with a dual choice olfactometer. In addition, we compared the antennal phenotypes in both populations. No statistical differences were found between the two populations at the behavioural level. Both showed a preference for face and feet extracts and this effect was abolished for face extracts after treatment with an antibacterial gel. The observation of the antennal phenotype showed that there were differences between both groups in the total length, total surface area and number and density of bristles. However, the number and density of chemoreceptive sensilla (basiconic and thin and thick-walled trichoids) and the total density of sensilla did not show statistically significant differences. These results demonstrate that colony insects, which have only been fed with living hens for the last 30 years, are attracted by human skin extracts in a similar way as F1 sylvatic insects.


Assuntos
Animais , Feminino , Humanos , Masculino , Antenas de Artrópodes/fisiologia , Comportamento Animal/fisiologia , Insetos Vetores/fisiologia , Feromônios , Rhodnius/fisiologia , Pele , Animais de Laboratório , Antenas de Artrópodes , Antenas de Artrópodes/ultraestrutura , Células Quimiorreceptoras/fisiologia , Quimiotaxia/fisiologia , Face , , Fenótipo , Rhodnius , Extratos de Tecidos
13.
Biol. Res ; 44(3): 277-282, 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-608624

RESUMO

About half of the human population is infected with Helicobacter pylori, a bacterium causing gastritis, peptic ulcer and progression to gastric cancer. Chemotaxis and flagellar motility are required for colonization and persistence of H. pylori in the gastric mucus layer. It is not completely clear which chemical gradients are used by H. pylori to maintain its position. TlpA, a chemotaxis receptor for arginine/ bicarbonate, has been identified. This study aimed to find out whether tlpA gene expression is required for the chemotactic response to arginine/bicarbonate. Wild-type motile H. pylori ATCC 700392 and H. pylori ATCC 43504, a strain having an interrupted tlpA gene, were used. Also, a tlpA-knockout mutant of H. pylori 700392 (H. pylori 700-tlpA::cat) was produced by homologous recombination. Expression of tlpA was assessed by a Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) assay. Chemotaxis was measured as a Relative Chemotaxis Response (RCR) by a modified capillary assay. H. pylori 700392 presented chemotaxis to arginine and sodium bicarbonate. H. pylori 700-tlpA::cat showed neither tlpA gene expression nor chemotaxis towards arginine and bicarbonate. Besides confirming that TlpA is a chemotactic receptor for arginine/bicarbonate in H. pylori, this study showed that tlpA gene expression is required for arginine/bicarbonate chemotaxis.


Assuntos
Arginina/farmacologia , Proteínas de Bactérias/genética , Bicarbonatos/farmacologia , Quimiotaxia/genética , Helicobacter pylori/genética , Proteínas de Membrana/genética , Expressão Gênica , Helicobacter pylori/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Ureia/metabolismo
14.
Braz. j. microbiol ; 41(2): 321-328, Apr.-June 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-545337

RESUMO

Regenerated extracellular NH4+in laboratory batch-cultures of the heterotrophic marine microzooplankter Oxyrrhis marina affects the strength and consistency of chemotaxes elicited by synthetic and biogenic chemoattractants. The ecological relevance of experiments with batch-cultured O. marina and limitations of the microcapillary assay for the study of chemosensory behaviours are discussed.


Assuntos
Movimento Celular , Quimiotaxia , Dinoflagelados , Microbiologia Ambiental , Eucariotos , Métodos , Métodos
15.
São Paulo; s.n; 2009. [114] p. graf.
Tese em Português | LILACS | ID: lil-587428

RESUMO

A doença de Behçet tem sua fisiopatologia caracterizada por hiperatividade neutrofílica, particularmente em relação à quimiotaxia, e períodos de atividade da doença podem ser desencadeados por exposição a estreptococos. Uma vez que células do sistema imune inato são ativadas pelo ácido lipoteicoico (LTA) de bactérias gram-positivas via receptor toll-like (TLR) 2 e CD14, cujas expressões são reguladas pelos fatores estimulantes de colônias de granulócitos (G-CSF) e granulócitos-macrófagos (GM-CSF), o objetivo principal deste estudo foi determinar se há hiperexpressão de TLR2 em neutrófilos de DB ativa e se a quimiotaxia de polimorfonucleares (PMN) neutrófilos na DB poderia ser hiperestimulada pelo LTA. Além do TLR2, foram medidas as expressões de TLR4, CD14, CD114 (receptor de G-CSF) e CD116 (receptor de GM-CSF) nos neutrófilos e nos monócitos de pacientes com doença de Behçet (DB), as concentrações séricas de CD14 solúvel (CD14s) e as respostas quimiotáxicas dos PMNs de DB sob diferentes estímulos. A expressão dos receptores foi medida pela citometria de fluxo, as concentrações séricas por ELISA e as respostas quimiotáxicas foram avaliadas em câmara de Boyden. Nos PMNs, os receptores foram igualmente expressos nos dois grupos e, estimulados com LTA, suas respostas quimiotáxicas também foram similares. Somente à incubação com plasma os PMNs de DB desenvolveram hiperquimiotaxia em relação aos PMNs controles. A expressão do TLR2 foi maior em monócitos de DB em relação aos controles, e a concentração de CD14s sérica, de origem monocitária, foi maior nos pacientes com DB ativa. Em conjunto, os resultados demonstram que PMNs de DB, isoladamente, não reagem exacerbadamente ao LTA, e suas respostas migratórias são estritamente dependentes de fatores estimulantes solúveis.


Expressions of toll-like receptor (TLR) 2, TLR4, CD14, CD114 and CD116 were assessed on polymorphonuclear (PMN) neutrophils and monocytes of patients with Behçets disease (BD). PMN chemotactic responses under different stimulations were also measured. The objective was to determine if BD PMN chemotaxis may be overstimulated by lipoteichoic acid (LTA) from gram-positive bacteria. Receptor expressions were measured by flow cytometry and PMN chemotaxis was assessed in a Boyden chamber. Only TLR2 expression was higher on monocytes of the BD group than in control group. On PMNs, however, TLR2 expression was similar in both groups and, when stimulated with LTA, BD PMN cells showed chemotactic responses similar to the controls. These cells only exhibited increased chemotaxis when incubated with plasma. In conclusion, isolated BD PMN did not overreact to LTA, and its hyperchemotaxis is strictly dependent on soluble stimulating factors.


Assuntos
Humanos , Masculino , Feminino , Quimiotaxia , Monócitos , Neutrófilos , Síndrome de Behçet/fisiopatologia
16.
Perionews ; 1(2): 133-140, abr.-jun. 2007. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-836849

RESUMO

Fatores de crescimento polipeptídicos são proteínas de baixo peso molecular sintetizadas por várias células e tecidos que regulam os eventos básicos que levam à regeneração periodontal: proliferação, quimiotaxia, diferenciação e síntese de matriz protéica. Embora diversos métodos terapêuticos tenham sido propostos para uso clínico visando a regeneração dos tecidos periodontais, a previsibilidade de sucesso ainda é limitada, com casos bem-sucedidos e outros mostrando resultados aquém do esperado. Recentemente, após a identificação da existência de células tronco no ligamento periodontal e a compreensão que a diferenciação destas células em outras mais diferenciadas (fibroblastos, osteoblastos e cementoblastos) é mediada por moléculas de sinalização (fatores de crescimento), alguns estudos foram publicados propondo a utilização clínica dos fatores de crescimento, isolados ou combinados, em diferentes tipos de veículos com o objetivo de favorecer a regeneração periodontal. Neste artigo, as características gerais e os estudos in vitro e in vivo evidenciando o papel dos principais fatores de crescimento utilizados na regeneração periodontal serão revistos com o objetivo de avaliar o papel dos fatores de crescimento na regeneração periodontal.


Polipeptidic growth factors are low density proteins secreted by different cells and tissues that regulate the basic events leading to periodontal regeneration: proliferation, chemotaxis, differentiation and protein synthesis. Although many methods for achieving regeneration of lost periodontal tissues have been suggested, there is poor predictability, with some well-succeeded cases and others showing unexpected results. Recently, after the identification of mesenchymal stem cells in the periodontal ligament and the understanding that the differentiation of these cells onto more differentiated ones (osteoblasts, cementoblasts, fibroblasts) is mediated by signaling molecules (growth factors), some studies have proposed the clinical use of growth factors isolated or in combination to enhance periodontal regeneration outcomes. In this paper, the characteristics and in vitro and the in vivo studies evaluating the role of growth factors in periodontal regeneration will be reviewed to evaluate the role of growth factors in periodontal regeneration.


Assuntos
Humanos , Quimiotaxia , Regeneração Tecidual Guiada Periodontal , Peptídeos e Proteínas de Sinalização Intercelular , Mitógenos , Periodontia
17.
Rev. MED ; 15(1): 94-104, ene. 2007.
Artigo em Espanhol | LILACS | ID: lil-451889

RESUMO

En los organismos multicelulares animales, las células epiteliales son estructuras dinámicas que están relacionadas en una compleja, exquisita y regulada serie de procesos fisiológicos, siendo de los más relevantes los relacionados con la absorción, el catabolismo y el reciclaje de nutrientes. De igual forma, estos organismos están en constante desafío debido a la continua interacción con una gran variedad de eventos aleatorios ambientales. Frente a esta serie de agentes potencialmente nocivos, las células epiteliales se constituyen en la primera línea de defensa, protección e interfase de intercambio. En esta revisión de tema se pretende realizar un abordaje de la información actual acerca de una maquinaria de transporte epitelial de absorción, que hace posible desencadenar una respuesta efectiva a tales eventos, se trata del complejo MegaCUBAM.


Assuntos
Humanos , Anemia Megaloblástica , Arteriosclerose , Células Epiteliais , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Autoimunidade , Quimiotaxia , Lipoproteínas
18.
Artigo em Espanhol | LILACS | ID: lil-513388

RESUMO

La necesidad de tratar las distintas patologías de la cirugía ortopédica han impulsado la búsqueda y desarrollo de materiales capaces de sustitur al hueso; de allí la utilización de plasma autólogo rico en factores de crecimiento derivado de las plaquetas (PRGF) para mejorar la respuesta osteogénica, estimulando los mecanismos de reparación mediante la activación de las funciones biológicas de quimiotaxis, angiogénesis, proliferación, diferenciación y modulación celular ósea y tisular. En esta técnica los FC los encontramos en el plasma rico en plaquetas (PRP), obtenido a partir de la sangre del mismo individuo, la cual se lleva a centrifiguración, separación de las porciones proteicas y se aplica de forma percutánea sobre el defecto óseo. Se presenta un paciente masculino, de 57 años de edad, quien el 1/10/04 sufre fractura abierta IIIB de 1/3 distal de tibia y peroné derecho; se realiza reducción y síntesis de clavo bloqueado y placa 1/3 de caña, con evaluación tórpida; se retira placa 1/3 de caña y se dinamiza clavo, resultando infructuoso. Acude a este servicio en abril del presente año (2007) donde posterior a valoración clínica y radiológica se evidencia retardo de consolidación ósea, iniciándose terapia de estimulación osteogénica con PRGF. Se colocan 2 dosis de 20cc con un período de distanciamiento de un mes entre cada una, con controles radiológicos a los 21 días posteriores de cada aplicación; obteniéndose signos clínicos y radiológicos de consolidación ósea.


Assuntos
Humanos , Masculino , Adulto , Autoantígenos , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/diagnóstico , Fraturas da Tíbia/terapia , Tíbia/cirurgia , Tíbia/lesões , Inibidores da Angiogênese , Ortopedia , Quimiotaxia/imunologia , Traumatologia
19.
Braz. j. med. biol. res ; 39(9): 1233-1240, Sept. 2006. ilus, graf
Artigo em Inglês | LILACS | ID: lil-435420

RESUMO

Glucocorticoids (Gc) influence the differentiation of neural crest-derived cells such as those composing sympathoadrenal tumors like pheochromocytomas, as well as neuroblastomas and gangliomas. In order to obtain further information on the effects of Gc on cells evolving from the neural crest, we have used the human neuroblastoma cell line SK-N-SH to analyze: 1) the presence and the binding characteristics of Gc receptors in these cells, 2) the effect of dexamethasone (Dex) on the migration of SK-N-SH cells, and 3) the effect of Dex on the organization of the cytoskeleton of SK-N-SH cells. We show that: 1) receptors that bind [³H]-Dex with high affinity and high capacity (Kd of 9.6 nM, Bmax of 47 fmol/mg cytosolic protein, corresponding to 28,303 sites/cell) are present in cytosolic preparations of SK-N-SH cells, and 2) treatment with Dex (in the range of 10 nM to 1 æM) has an inhibitory effect (from 100 percent to 74 and 43 percent, respectively) on the chemotaxis of SK-N-SH cells elicited by fetal bovine serum. This inhibition is completely reversed by the Gc receptor antagonist RU486 (1 æM), and 3) as demonstrated by fluorescent phalloidin-actin detection, the effect of Dex (100 nM) on SK-N-SH cell migration is accompanied by modifications of the cytoskeleton organization that appear with stress fibers. These modifications did not take place in the presence of 1 æM RU486. The present data demonstrate for the first time that Dex affects the migration of neuroblastoma cells as well as their cytoskeleton organization by interacting with specific receptors. These findings provide new insights on the mechanism(s) of action of Gc on cells originating in the neural crest.


Assuntos
Humanos , Movimento Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Neuroblastoma/patologia , Forma Celular , Quimiotaxia , Linhagem Celular Tumoral/efeitos dos fármacos , Neuroblastoma/química , Receptores de Glucocorticoides/análise
20.
Lecta-USF ; 22(1/2): 27-35, jan.-dez. 2004. graf
Artigo em Português | LILACS | ID: lil-418982

RESUMO

O óxido nítrico (NO) é sintetizado pela ação das enzimas NO sintase endoletial (eNOS), neuronal (bNOS) e induzível (iNOS). Nossos resultados anteriores demonstram que os eosinófilos apresentam um sistema funcional de NO sintases e que este mediador possui um papel importante na locomoção de eosinófilos de ratos. O objetivo deste trabalho foi investigar se o NO está envolvido na migração de eosinófilos de pacientes com rinite alérgica, assim como caracterizar farmacologicamente as isoformas de NO sintase envolvidas no processo. Nossos resultados sugerem a inexistência da expressão da iNOS noseosinófilos dos pacientes atópicos provavelmente decorrente da exposição prévia destas células ao cortizol endógino aumentado nos pacientes com rinite alérgica.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Quimiotaxia , Óxido Nítrico/efeitos adversos , Rinite , Rinite/etiologia , Hipersensibilidade a Drogas , Eosinófilos
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