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1.
J Biomed Mater Res B Appl Biomater ; 112(1): e35314, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37565785

RESUMO

The development and evaluation of synthesis materials are crucial to reducing the morbidity and magnitude of post-enterorrhaphy surgical complications. Despite the possibility of production, chitosan thread has not yet been used in enterorrhaphy, and its effects on intestinal healing have not been evaluated. Therefore, this study aimed to evaluate the effects of chitosan thread on the intestinal wall repair of rabbits submitted to cecorrhaphy. For this, 42 rabbits were allocated into two groups with 21 animals. One group was submitted to cecorrhaphy with chitosan suture thread (CG) and the other with poliglecaprone suture thread (PG). The occurrence of postoperative complications, the intensity of edema, cellular response, formation of granulation tissue, as well as the deposition and maturation of collagen fibers, and the intensity of vascular endothelial growth factor (VEGF-α) expression, were evaluated during the intestinal wall repair process. The evaluations occurred on the 5th, 15th, and 25th postoperative (PO) days. The animals did not develop peritonitis, but adherence was observed in six animals from CG and seven from PG, with no difference between groups. The polymorphonuclear infiltrate showed higher intensity and higher amount of type III collagen fibers in CG on the 15th PO day. In contrast, a lower amount of type I collagen fibers was observed in CG samples on the 25th PO day. Therefore, the chitosan thread used for cecorrhaphy in rabbits results in minimal postoperative complications, presents biocompatibility, and bioactively assists the tissue repair process of the cecal wall, inducing minimal tissue reaction, stimulating the deposition of type III collagen fibers in the proliferative phase, with sustained VEGF-α expression, but with reduced deposition of type I fibers, indicating a delay in collagen maturation.


Assuntos
Quitosana , Animais , Coelhos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização , Colágeno Tipo III , Colágeno , Complicações Pós-Operatórias
2.
Drug Deliv Transl Res ; 10(6): 1675-1687, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32562253

RESUMO

Macrophages have unique surface receptors that might recognize preferentially several moieties present on the surface of infecting organisms, including in the bacterial cell wall. Benefiting from a similar composition regarding the referred moieties, polysaccharides might be good candidates to compose the matrix of drug carriers aimed at macrophage targeting, as they can use the same recognition pathways of the infecting organisms. Carrageenan (CRG), a polysaccharide extracted from red edible seaweed, is an interesting possibility for the approach of directly targeting alveolar macrophages, as its composition is reported to be recognized by several macrophage lectin receptors. Inhalable starch/CRG microparticles were successfully produced, effectively associating isoniazid (96%) and rifabutin (74%) simultaneously. Furthermore, the produced microparticles presented adequate aerodynamic properties for pulmonary delivery with potential to reach the respiratory zone, with a mass median aerodynamic diameter (MMAD) between 3.3 and 3.9 µm. It was further demonstrated that the antitubercular activity of the drugs remained unchanged after encapsulation. The formulation evidenced no cytotoxic effects on lung epithelial cells (A549), although mild toxicity was observed on macrophage-differentiated THP-1 cells for the drug-loaded formulation. Starch/CRG microparticles also exhibited a propensity to be captured by macrophages in a dose-dependent manner, as well as an ability to activate the target cells. This work provides indications on the potential of the starch/CRG carriers to interact with macrophages, thus providing a platform for drug delivery in the context of macrophage intracellular diseases. Additionally, if tuberculosis is focused, these microparticles can be used as inhalable drug carriers. Graphical abstractz.


Assuntos
Antituberculosos/administração & dosagem , Carragenina/química , Portadores de Fármacos/química , Macrófagos/efeitos dos fármacos , Rodófitas , Administração por Inalação , Humanos , Rodófitas/química , Células THP-1 , Tuberculose/tratamento farmacológico
3.
J Food Sci Technol ; 56(5): 2721-2736, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31168154

RESUMO

Nanoemulsions exhibit a number of advantages to carry and deliver lipophilic compounds such as essential oils (EOs) due to their good stability and high surface area per volume unit. The purpose of this work was to assess the long-term stability of nanoemulsions of clove and lemongrass (LG) EOs and their principal components eugenol and citral (CI), respectively, at 3 different concentrations (2, 5 or 10 times their respective minimum inhibitory concentrations) and at two storage temperatures (1 °C and 21 °C). The initial droplet size of LG and CI-loaded nanoemulsions was below 100 nm and most of them kept droplet sizes in the nano-range until the end of storage at both temperatures. The ζ-potential was lower than - 40 mV, but it increased through storage, indicating a weaker alginate adsorption at the oil surface at both temperatures. The antimicrobial activity increased with the EOs concentration and was negatively affected by the highest storage temperature. Nanoemulsions containing CI and LG were able to significantly decrease Escherichia coli counts during storage, particularly at 1 °C. Nanoemulsions containing 1.0 and 2.0% w/w CI and 2.5% w/w LG were the most efficient in reducing Botrytis cinerea growth through storage, mainly at 1 °C. The nanoemulsions containing 1.0 and 2.0% w/w CI, as well as, 1.25 and 2.5% w/w LG better maintained their stability and antimicrobial effect along 6-months storage mainly when at 1 °C, making those nanoemulsions suitable as edible coatings for food preservation. Future studies should be oriented to evaluate the impact of these nanoemulsions on the organoleptic properties of coated foods and their potential toxicity.

4.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 82-92, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-888062

RESUMO

Gene expression of CDKN1A, CDKN1B, and TP53, and immunostaining of p21, p27 and p53 were evaluated to verify the role of these cell cycle inhibitors in canine prostates with proliferative inflammatory atrophy-PIA and prostatic carcinoma-PC. Seventy samples, 15 normal, 30PIA and 25PC. Regarding number of p27 and p53 labeled cells, difference between normal and PIA and PC was observed, as well as between PIA and PC for p53. Immunostaining intensities of p21, p27 and p53 were different when comparing normal tissues to PIA and PC. Sixteen cDNA of canine prostatic FFPE tissue were subjected to RT-PCR and RT-qPCR, four normal, three PIA, and nine PC. CDKN1A mRNA was detected in four PC by RT-PCR, and it was overexpressed when compared to normal by RT-qPCR, in one PIA and six PC. CDKN1B mRNA was detected in three PC by RT-PCR and it was overexpressed in three PC and decreased in one PC. TP53 mRNA was overexpressed in one PIA and three PC. In conclusion, when overexpressed in canine prostate with premalignant and malignant, p21 and p27 play a role controlling cell proliferation, working as a protective factor in the evolution of PIA to PC, and in the PC development, even in the presence of altered p53.(AU)


A expressão gênica de CDKN1A, CDKN1B e TP53, assim como imunomarcação de p21, p27 e p53 foram realizadas a fim de verificar o papel desses inibidores do ciclo celular na próstata canina com atrofia inflamatória proliferativa (PIA) e carcinoma prostático (PC). Foram obtidas70 amostras de próstata canina, sendo 15 de tecido normal, 30 de PIA e 25 de PC. Quanto ao número de células imunomarcadas foi observada diferença entre amostras normais, com PIA e PC para p27 e p53, assim como entre PIA e PC para p53. Para a intensidade de imunomarcação houve diferença entre os tecidos normais e com PIA e PC para p21, p27 e p53. Foram obtidas dezesseis amostras de cDNA a partir de amostras de próstatas caninas embebidas em parafina para a realização da RT-PCR e RT-qPCR, sendo quatro normais, três com PIA, e nove com o PC. O gene CDKN1A foi detectado em quatro das amostras com PC por RT-PCR, e pela RT-qPCR este estava superexpresso em uma PIA e em seis PC quando da comparação com o tecido prostático normal. O CDKN1B foi detectado em três PC por RT-PCR e pela RT-qPCR estava superexpresso em três PC e reduzido em um PC. O TP53 foi detectado em todas as próstatas caninas com PIA e PC por RT-PCR, sendo também superexpresso em uma glândula com PIA e em três com PC. Concluiu-se que p21 e p27 quando superexpressas na próstata canina com lesões pré-malignas (PIA) e malignas (PC) desempenham ação no controle da proliferação celular, possivelmente atuando como fator de proteção na evolução da PIA para PC, e no desenvolvimento do PC, mesmo na presença de p53 alterada. Assim, o próximo passo é avaliar essas proteínas do ciclo celular em casos de PC canino com metástase.(AU)


Assuntos
Animais , Cães , Próstata/fisiologia , Atrofia/diagnóstico , Carcinoma , Ciclo Celular , Cães/anatomia & histologia , Cães/anormalidades
5.
Polymers (Basel) ; 10(6)2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-30966670

RESUMO

The pulmonary delivery of antitubercular drugs is a promising approach to treat lung tuberculosis. This strategy not only allows targeting the infected organ instantly, it can also reduce the systemic adverse effects of the antibiotics. In light of that, this work aimed at producing fucoidan-based inhalable microparticles that are able to associate a combination of two first-line antitubercular drugs in a single formulation. Fucoidan is a polysaccharide composed of chemical units that have been reported to be specifically recognised by alveolar macrophages (the hosts of Mycobacterium). Inhalable fucoidan microparticles were successfully produced, effectively associating isoniazid (97%) and rifabutin (95%) simultaneously. Furthermore, the produced microparticles presented adequate aerodynamic properties for pulmonary delivery with potential to reach the respiratory zone, with a mass median aerodynamic diameter (MMAD) between 3.6⁻3.9 µm. The formulation evidenced no cytotoxic effects on lung epithelial cells (A549), although mild toxicity was observed on macrophage-differentiated THP-1 cells at the highest tested concentration (1 mg/mL). Fucoidan microparticles also exhibited a propensity to be captured by macrophages in a dose-dependent manner, as well as an ability to activate the target cells. Furthermore, drug-loaded microparticles effectively inhibited mycobacterial growth in vitro. Thus, the produced fucoidan microparticles are considered to hold potential as pulmonary delivery systems for the treatment of tuberculosis.

6.
Arq. bras. med. vet. zootec. (Online) ; 70(3): 741-748, maio-jun. 2018. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-911223

RESUMO

Feridas cutâneas em bovinos são um constante desafio clínico cirúrgico por desencadearem perdas econômicas bastante significativas. O látex proveniente da seiva da seringueira (Hevea brasiliensis) apresenta potencial terapêutico para incrementar o processo de reparação tecidual. Portanto, pretendeu-se com esse estudo avaliar o tipo de reação tecidual e os possíveis mecanismos de angiogênese desencadeados pelo implante de uma membrana de látex natural em bovinos. Para tal, foram utilizados seis bovinos da raça Nelore, submetidos ao implante subcutâneo experimental de três fragmentos de membranas de látex natural. Foram coletadas amostras de tecido e da membrana aos 15, 30 e 45 dias após a implantação, para avaliações histológicas, ultraestruturais por microscopia eletrônica de varredura e imunoistoquímicas com anticorpos antimarcador de macrófagos (MAC), CYR 61 e VEGF. O implante de látex proporcionou aumento da angiogênese e reparação tecidual em bovinos, não mediada pela expressão do VEGF e CYR 61.(AU)


Cattle wounds are a constant surgical and clinical challenge, leading to important economical losses. The latex from the sap of the rubber tree (Hevea brasiliensis) has therapeutic potential to enhance tissue repair process. Therefore, we evaluated the type of tissue reaction and possible mechanisms of angiogenesis triggered by implanting natural latex rubber in bovine species. Six Nelore bovines were subjected to subcutaneous experimental implant of three fragments of natural rubber latex membranes. Tissue and rubber membrane samples were harvested at 15, 30 and 45 days implantation for histology, scanning electron microscopy and immunohistochemical evaluation with anti macrophage marker (MAC), anti CYR 61, anti VEGF antibodies. The latex membrane estimulates tissue reaction and repair and significant angiogenesis stimuli without activating CYR 61 and VEGF pathways.(AU)


Assuntos
Animais , Bovinos , Bovinos/lesões , Regeneração Tecidual Guiada/estatística & dados numéricos , Regeneração Tecidual Guiada/veterinária , Hevea/química , Cicatrização
7.
Integr Med Insights ; 12: 1178633717702869, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28469409

RESUMO

The beneficial effects of honey on human health have long been recognized. Today, many of those positive effects have been studied to elucidate its mode of action. This review briefly summarizes the best studied features of honey, highlighting it as an appealing alternative medicine. In these reports, the health benefits of honey range from antioxidant, immunomodulatory, and anti-inflammatory activity to anticancer action, metabolic and cardiovascular benefits, prebiotic properties, human pathogen control, and antiviral activity. These studies also support that the honey's biological activity is mainly dependent on its floral or geographic origin. In addition, some promising synergies between honey and antibiotics have been found, as well as some antiviral properties that require further investigation. Altogether, these studies show that honey is effectively a nutraceutical foodstuff.

8.
Arq. bras. med. vet. zootec ; 68(3): 658-666, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: lil-785681

RESUMO

The canine transmissible venereal tumor (TVT) affects the external genitalia of dogs by the natural transplant of viable tumor cells. Thus, this research aimed to diagnose and characterize TVT morphological patterns, identify the insertion of the LINE-1 element in C-MYC gene, by means of the polymerase chain reaction (PCR), and evaluate the immunohistochemical expression of C-MYC, p53, p21 and p27 proteins. The relationship between C-MYC and p53 proteins and their interference on the expression of p21 and p27 were also studied. For that, 20 samples of naturally occurring TVT were used, subjected to cytopathological, histopathological and immunohistochemical analysis, and to molecular diagnosis of neoplasia. The increased tissue expression and the correlation among C-MYC, p53, p21 and p27 proteins indicate reduction and/or loss of their functionality in the TVT microenvironment, with consequent apoptotic suppression, maintenance of cell growth and progression of neoplasia.(AU)


O tumor venéreo transmissível canino (TVT) afeta a genitália externa de cães pelo transplante natural de células tumorais viáveis. Assim, esta pesquisa teve como objetivo diagnosticar e caracterizar TVT em padrões morfológicos, identificar a inserção do elemento LINE-1 em gene C-MYC, por meio da reação em cadeia da polimerase (PCR), e avaliar a expressão imuno-histoquímica do C-MYC, p53, p21 e p27. A relação entre C-MYC e as proteínas p53 e a sua interferência na expressão de p21 e p27 foram também estudadas. Para isso, foram utilizadas 20 amostras de ocorrência natural de TVT, submetido a exame citopatológico, histopatológica e imuno-histoquímica e ao diagnóstico molecular de neoplasia. A expressão aumentada do tecido e a correlação entre a C-MYC e as proteínas p53, p21 e p27 indicam redução e/ou perda de funcionalidade na TVT em seu microambiente, com consequente supressão apoptótica, manutenção do crescimento celular e progressão da neoplasia.(AU)


Assuntos
Animais , Cães , Genes myc , Genitália Masculina/patologia , Células Neoplásicas Circulantes/imunologia , Tumores Venéreos Veterinários/diagnóstico , Tumores Venéreos Veterinários/imunologia , Biologia Celular , Forma do Núcleo Celular , Testes Imunológicos/veterinária , Neoplasias/veterinária , Reação em Cadeia da Polimerase/veterinária
9.
Nat Prod Commun ; 11(7): 1029-1038, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30452188

RESUMO

The in viro antioxidant, anti-inflammatory, anti-hyperglycaemic, and anti-acetylcholinesterase activities of the essential oils (EOs) isolated from six Lamiaceae species (Thymbra capitata,. Thymus albicans, Th. caespititius, Th. carnosus, Th. lotocephalus and Th. mastichina) grown in Portugal, were evaluated. Th. caespititius and T. capitata carvacrol/thymol-rich EOs showed the best capacity for preventing lipid peroxidation, and scavenging the 2,2'-azino- bis(3-ethylbenzothiazoline-6-sulphonid acid) (ABTS) and peroxyl free radicals, as well as for inhibiting lipoxygenase and a-amylase. However, Th. caespititius and Th. lotocephalus 1,8-cineole and linalool rich EOs were the best inhibitors of a-glucosidase. T capitata, Th. lotocephalus and Th. albicans EOs were the: most active for inhibiting acetyleholinesterase. Th. caespititius and Th. mastichina EOs were the main scavengers of nitric oxide (NO) radicals. The comparison between the present data with a survey of the existing literature on the in vitro biological activities of the essential oils isolated from the same species from Portuguese origin, using other.methodologies, showed some differences. For instance the use of two oxidizable substrates (egg yolk andlecithin liposomes) led to distinct results mainly for those samples with relatively low activity. In addition, the EOs capacity for scavenging peroxyl radicals-was also influenced by the presence of cyclodextrins, as a synergism seemed to occur between EOs and those carbohydrates.


Assuntos
Anti-Inflamatórios/química , Antioxidantes/química , Hipoglicemiantes/química , Lamiaceae/química , Óleos de Plantas/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/farmacologia , Lecitinas/química , Peroxidação de Lipídeos , Lipossomos/química , Inibidores de Lipoxigenase/química , Inibidores de Lipoxigenase/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/química , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/metabolismo
10.
Chem Biodivers ; 11(5): 719-32, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24827682

RESUMO

Volatile-oils chemical composition and bioactivity of the essentail oils from Plectranthus barbatus, P. neochilus, and P. ornatus (Lamiaceae) were assessed. Aerial parts from these three related Plectranthus species were collected from cultivated plants grown in Portugal, during vegetative and flowering phases. Volatiles, isolated by distillation-extraction, were analyzed by GC and GC/MS. Monoterpene hydrocarbons (12-74%) and sesquiterpene hydrocarbons (4-45%) constituted the main fractions in all volatiles. α-Pinene (3; 12-67%), oct-1-en-3-ol (6; traces-28%), ß-pinene (7; 0.1-22%), and ß-caryophyllene (50; 7-12%) dominated P. barbatus volatiles. P. neochilus major volatile components were α-terpenyl acetate (41; traces-48%), α-thujone (2; 2-28%), ß-caryophyllene (50; 2-28%), ß-pinene (7; 1-25%), and α-pinene (3; 1-19%). Oct-1-en-3-ol (6; 13-31%), ß-pinene (7; 11-24%), α-pinene (3; 11-19%), and ß-caryophyllene (50; traces-11%) were the main constituents from P. ornatus volatiles. These chemical compositions were rather different from those previously found for specimens harvested in Africa and Brazil. Moreover, the volatiles from the flowers are herewith reported for the first time. Essential oils, isolated by hydrodistillation from leaves and stems, showed a yellowish color and unpleasant odor, with yields ranging from 0.08% to 0.84% (v/dry weight). Antioxidant and antimicrobial activities of the essential oils were evaluated by DPPH· and TBARS assays, and agar disc-diffusion method, respectively. Results showed low or moderate antioxidant capacity and significant antimicrobial activity against Gram-positive bacteria.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Óleos Voláteis/química , Óleos de Plantas/química , Plectranthus/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Fungos/efeitos dos fármacos , Humanos , Micoses/tratamento farmacológico , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/farmacologia
11.
Int J Food Microbiol ; 163(2-3): 51-63, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23558187

RESUMO

The gastrointestinal system poses different stresses to the foodborne pathogen, Listeria monocytogenes, including the low pH of the stomach and the presence of bile and the high osmolality of the intestinal fluid. The present study evaluated how previous exposure of three L. monocytogenes dairy isolates (C882 and T8, serovar 4b isolates and A9 serovar 1/2a or 3b isolate) to a cheese-simulated medium (p H5.5 and 3.5% NaCl [w/v], adapted cultures) affected subsequent survival in a simulated gastrointestinal system. Listerial cultures exposed to the cheese-simulated medium at pH7.0, with no added NaCl, were considered non-adapted. To investigate the main events involved in listerial survival during the gastric and intestinal subsequent challenge, a proteomic approach was used. All L. monocytogenes strains were able to survive the deleterious effects of the gastrointestinal fluids and no significant differences were observed between adapted and non-adapted cells. However the L. monocytogenes strains showed a different protein pattern in response to the gastrointestinal stress. Data indicated that synthesis of stress related proteins is more pronounced in non-adapted cells. Although, a significant number of enzymes involved in glycolysis and energy production were also consistently over-produced by the three strains. These findings provided new insights into the means used by L. monocytogenes to overcome the gastrointestinal system and allow the pathogen to move to the next phase of the infectious process.


Assuntos
Trato Gastrointestinal/química , Regulação Bacteriana da Expressão Gênica , Listeria monocytogenes/genética , Proteoma/genética , Proteínas de Bactérias/genética , Queijo/microbiologia , Proteínas de Choque Térmico/genética , Concentração de Íons de Hidrogênio , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/isolamento & purificação , Viabilidade Microbiana , Proteoma/efeitos dos fármacos , Proteômica , Cloreto de Sódio/farmacologia
12.
Lett Appl Microbiol ; 56(6): 421-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23461530

RESUMO

UNLABELLED: The aim of this study was to evaluate the effect of the acid and salt adaptation in a cheese-based medium on the virulence potential of Listeria monocytogenes strains isolated from cheese and dairy processing environment using the Galleria mellonella model. Four L. monocytogenes strains were exposed to a cheese-based medium in conditions of induction of an acid tolerance response and osmotolerance response (pH 5·5 and 3·5% w/v NaCl) and injected in G. mellonella insects. The survival of insects and the L. monocytogenes growth kinetics in insects were evaluated. The gene expression of hly, actA and inlA genes was determined by real-time PCR. The adapted cells of two dairy strains showed reduced insect mortality (P < 0·05) in comparison with nonadapted cells. Listeria monocytogenes Scott A was the least virulent, whereas the cheese isolate C882 caused the highest insect mortality, and no differences (P > 0·05) was found between adapted and nonadapted cells. The gene expression results evidenced an overexpression of virulence genes in cheese-based medium, but not in simulated insect-induced conditions. Our results suggest that adaptation to low pH and salt in a cheese-based medium can affect the virulence of L. monocytogenes, but this effect is strain dependent. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, the impact of adaptation to low pH and salt in a cheese-based medium on L. monocytogenes virulence was tested using the Wax Moth G. mellonella model. This model allowed the differentiation of the virulence potential between the L. monocytogenes strains. The effect of adaptation on virulence is strain dependent. The G. mellonella model revealed to be a prompt method to test food-related factors on L. monocytogenes virulence.


Assuntos
Queijo , Listeria monocytogenes/fisiologia , Listeria monocytogenes/patogenicidade , Mariposas/microbiologia , Adaptação Fisiológica , Animais , Toxinas Bacterianas/biossíntese , Queijo/microbiologia , Proteínas de Choque Térmico/biossíntese , Proteínas Hemolisinas/biossíntese , Concentração de Íons de Hidrogênio , Listeria monocytogenes/genética , Listeria monocytogenes/isolamento & purificação , Tolerância ao Sal , Cloreto de Sódio , Virulência
13.
Foodborne Pathog Dis ; 10(2): 107-19, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23441912

RESUMO

Ingestion of contaminated dairy products, in particular soft cheese, is one of the major routes of infection by the human pathogen Listeria monocytogenes. During cheese processing, this foodborne pathogen is exposed to sublethal acid and osmotic stress conditions, which may induce tolerance responses and influence subsequent survival in the gastric tract. The aim of the current study was to evaluate the impact on a L. monocytogenes cheese isolate (serotype 4b) and two cheese dairy isolates (T8, serotype 4b, isolated from vat; and A9, serotype 1/2b or 3b, isolated from shelf stand) of exposure to sublethal conditions of pH and salt (5.5 and 3.5% [w/v] NaCl) in a cheese-simulated medium and further challenge with gastric stress. The bacterial cells exposed to pH 7.0 and no added salt were considered non-adapted. Via two-dimensional gel electrophoresis (2-DE), the proteomes of cheese-simulated medium and gastric challenged Listeria cells were compared. All L. monocytogenes isolates were able to survive the high acidity of gastric fluid (pH 2.5), and no significant differences were observed between adapted and non-adapted cells. However, the analysis of the intracellular proteome profiles revealed a significant intra-strain variation in the protein arsenal used to respond to the adaptation in the cheese-based medium and to the gastric stress. In cheese-based medium, the three strains produced different stress proteins. All three strains showed a higher abundance of carbohydrate proteins, but there was no overlap between them. Exposure to the gastric fluid induced the production of a group of proteins in T8 adapted and non-adapted cells that had not been detected previously in the cheese-based proteome. No such response was shown by A9 and C882 strains. Taken together, this study evidences the proteome tools used by adapted and non-adapted cells to cope with the hostile microenvironment of the stomach.


Assuntos
Proteínas de Bactérias/análise , Queijo/microbiologia , Trato Gastrointestinal/microbiologia , Listeria monocytogenes/patogenicidade , Proteoma/análise , Estresse Fisiológico , Adaptação Fisiológica , Eletroforese em Gel Bidimensional , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Humanos , Concentração de Íons de Hidrogênio , Listeria monocytogenes/isolamento & purificação , Osmose , Proteômica , Cloreto de Sódio
14.
Rev. bras. farmacogn ; 21(6): 1012-1024, Nov.-Dec. 2011. graf, tab
Artigo em Inglês | LILACS | ID: lil-602297

RESUMO

Thyme essential oils are well recognized by their excellent biological activities and the antimicrobial activity of Portuguese thyme essential oils has been investigated with promising results, particularly against food borne pathogens. In this study the potential antimicrobial activity of the essential oils of five species of Thymus (Lamiaceae), namely Th. caespititius Brot., Th. camphoratus Hoffmanns. & Link, Th. capitellatus Hoffmanns. & Link., Th. carnosus Boiss. and Th. zygis L. was evaluated against Candida albicans, Haemophilus influenza, Helicobacter pylori, Listeria monocytogenes, Salmonella enterica and Streptococcus pneumoniae. H. pylori strains were the most susceptible bacteria, particularly to the essential oils of Th. caespititius (Planalto Central), Th. zygis (Rebordãos) and Th. caespititius (Pico) which minimum inhibitory concentration (MIC) values ranged from 0.05 to 0.08 mg.mL-1. Th. caespititius essential oil from Planalto Central or its main component, carvacrol significantly (p<0.05) inhibited the intracellular growth of H. pylori, and showed no citotoxicity to the gastric cell line. Our results suggest the potential of this essential oil and its main component as a promising tool as anti-Helicobacter agent potentiating the eradication of this important gastroduodenal pathogen.

15.
Arq. bras. med. vet. zootec ; 63(6): 1368-1376, dez. 2011. ilus
Artigo em Português | LILACS | ID: lil-608958

RESUMO

Confeccionou-se um microarranjo de tecido (TMA) com 146 amostras de lesões prostáticas caninas. Este continha 17,2 por cento de hiperplasia prostática benigna (HPB), 32,4 por cento de atrofia inflamatória proliferativa (PIA), 2,6 por cento de prostatite, 8,6 por cento de focos de neoplasia intraepitelial prostática (PIN), 29,1 por cento de carcinomas e 9,3 por cento de próstatas normais. Cortes histológicos sequenciais foram feitos e utilizados para reação de imunoistoquímica com os anticorpos primários anti-p-53, anti-NOS-2 e anti-GSTP. Avaliou-se de cada core o escore de células marcadas para cada anticorpo utilizado. Os resultados foram tabulados por grupo diagnóstico e submetidos ao teste Tuckey. Os carcinomas prostáticos do cão e a PIA apresentaram maior número de amostras (41) com mais de 75 por cento das células positivas para NOS-2, demonstrando a influência do estresse oxidativo no desenvolvimento dessas lesões. As próstatas normais e as afecções desta glândula, HPB, PIA, PIN, prostatite e carcinoma, expressaram a proteína GSTP-1, o que conferiu proteção ao tecido prostático canino a danos oxidativos. A proteína p53 estava presente em todas as amostras estudadas, incluindo o tecido prostático normal, porém as lesões prostáticas apresentaram maior número de amostras com escores mais elevados de marcação (escores três e quatro), presente em 95 por cento dos focos de PIA e carcinoma. Concluiu-se que o aumento de expressão de óxido nítrico nas lesões prostáticas no cão e a expressão de GSTP-1 podem ter protegido o tecido prostático canino e que a expressão de p53 foi positiva e uniforme nas próstatas normais e com lesões hiperplásicas e displásicas.


A tissue microarray (TMA) with 149 samples of canine prostatic lesions contained 17.2 percent benign prostatic hyperplasia (BPH), 32.4 percent proliferative inflammatory atrophy (PIA), 2.6 percent prostatitis, 8.6 percent foci prostatic intraepithelial neoplasia (PIN), 29.1 percent carcinomas and 9.3 percent normal prostates. Sequential histological sections were made and used for immunohistochemistry reaction with primary antibodies anti p-53, anti-NOS-2 and anti-GSTP. The score for each antibody employed was evaluated. The results were tabulated by diagnostic group and subjected to Tuckey test. Prostatic carcinomas and PIA had a higher number of samples (41) with over 75 percent of cells positive for NOS-2, demonstrating the influence of oxidative stress in the development of these lesions. The prostates of normal dogs, as well as the disorders of this gland (BPH, PIA, PIN, prostatitis and carcinoma), expressed GSTP-1 protein, which gives protection to the canine prostate tissue against oxidative damage. The p53 protein was present in all samples studied, including normal prostate tissue, but the prostatic lesions had a higher number of samples with higher scores (more than 50 percent of positive cells), in 95 percent of foci of PIA and carcinoma. It was found that an increased expression of NO in prostatic lesions of dogs and that the expression of GSTP-1 can protect the canine prostate tissue, which would contribute to the low frequency of prostate adenocarcinoma in this species. The expression of p53 was positive in all lesions as well as the in normal prostate.

16.
Nat Prod Res ; 25(5): 526-41, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21391115

RESUMO

Salvia officinalis L. oils were isolated from the plant's commercial dried aerial parts, by hydrodistillation, with different distillation times. The essential oils were analysed by gas chromatography and gas chromatography-mass spectrometry. The antioxidant ability was measured using a free radical scavenging activity assay using 2,2-diphenyl-1-picrylhydrazyl (DPPH), a thiobarbituric acid reactive substances (TBARS) assay, a deoxyribose assay for the scavenging of hydroxyl radical, an assay for site-specific actions and a 5-lipoxygenase assay. Antibacterial activity was determined by the agar diffusion method. 1,8-Cineole, α-pinene and camphor were the dominant components of all the essential oils. The different hydrodistillation times did not affect the oil yield nor the relative amount of the oil components. The time of hydrodistillation influenced the antioxidant activity. With the DPPH method, the oils isolated for 2 and 3 h were stronger free radical scavengers, while with the TBARS method, the highest antioxidant values were obtained in the oils isolated for 30 min, 2 and 3 h. Hydroxyl radical scavenging and lipoxygenase activity assays showed the best results with oils isolated for 1 and 3 h. With the deoxyribose method, sage oils at concentrations <1000 mg L(-1) showed better activity than mannitol. The essential oil of S. officinalis showed very weak antimicrobial activity.


Assuntos
Anti-Infecciosos/metabolismo , Antioxidantes/metabolismo , Óleos Voláteis/química , Salvia officinalis/química , Anti-Infecciosos/química , Antioxidantes/química , Monoterpenos Bicíclicos , Cânfora/análise , Cicloexanóis/análise , Destilação , Eucaliptol , Cromatografia Gasosa-Espectrometria de Massas , Monoterpenos/análise , Óleos Voláteis/análise , Substâncias Reativas com Ácido Tiobarbitúrico , Fatores de Tempo
17.
Arq. bras. med. vet. zootec ; 62(3): 596-602, June 2010. ilus
Artigo em Português | LILACS | ID: lil-554928

RESUMO

Avaliou-se histologicamente a próstata de 30 cães adultos e idosos sexualmente intactos que apresentavam ou não sintomatologia clínica de doença prostática, e verificou-se a incidência de possíveis alterações da glândula. Dentre as alterações encontradas, a hiperplasia prostática benigna constituiu o diagnóstico mais comum, 85,6 por cento (n=24), seguida por prostatite crônica, 64,3 por cento (n=18), displasia do epitélio glandular, 42,8 por cento (n=12), atrofia do epitélio glandular, 39,3 por cento (n=11), infiltrado inflamatório focal, 25 por cento (n=7), dilatação glandular focal, 21,4 por cento (n=6), prostatite aguda, 7,1 por cento (n=2), metaplasia escamosa, 3,6 por cento, (n=1), metástase de neoplasia sistêmica, 3,6 por cento (n=1) e abscesso prostático, 3,6 por cento (n=1). Como em muitos casos os cães são assintomáticos, ressalta-se a importância da realização rotineira de exames clínicos específicos, como o toque retal e a ultrassonografia, para o diagnóstico precoce e o tratamento das afecções prostáticas.


The prostates of 30 not castrated old dogs with or without clinical symptoms of prostatic disease were histologically evaluated. It was observed the incidence of possible changes in the gland. Among the changes, benign prostatic hyperplasia (BPH) was the most common diagnosis, accounting for 85.6 percent (n=24), followed by chronic prostatitis, 64.3 percent (n=18), dysplasia of the glandular epithelium, 42.8 percent (n=12), atrophy of the glandular epithelium, 39.3 percent (n=11), focal inflammatory infiltrate, 25 percent (n=7), focal glandular dilation, 21.4 percent (n=6), acute prostatitis, 7.1 percent (n=2), squamous metaplasia, 3.6 percent (n=1), metastasis of systemic neoplasia, 3.6 percent (n=1), and prostatic abscess, 3.6 percent (n=1). Because the lack of symptoms in most of dogs with prostatic changes, the specific clinic exams in routine, as rectal palpation and ultrasonography, are very important to early diagnosis and treatment of dogs with prostatic disease.


Assuntos
Animais , Masculino , Cães , Prevenção de Doenças , Doenças Prostáticas/veterinária , Próstata/anatomia & histologia , Cães , Hiperplasia Prostática/veterinária , Prostatite/veterinária
18.
J Hazard Mater ; 166(2-3): 706-13, 2009 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-19135795

RESUMO

Biological treatment with sulphate-reducing bacteria (SRB) has been considered as the most promising alternative for acid mine drainage (AMD) decontamination. Normally, these wastewaters contain high concentrations of sulphate and heavy metals, so the search for SRB highly resistant to metals is extremely important for the development of a bioremediation technology. A SRB consortium resistant to high concentrations of heavy metals (Fe, Cu and Zn), similar to those typically present in AMD, was obtained among several environmental samples, from a wastewater treatment plant. The phylogenetic analysis of the dsr gene sequence revealed that this consortium contains species of SRB affiliated to Desulfovibrio desulfuricans and Desulfobulbus rhabdoformis. The results show that the presence of usually lethal concentrations of Fe (400mg/L), Zn (150 mg/L) and Cu (80 mg/L) is not toxic for the sulphate-reducing bacteria present in this sample. As a consequence, a very good efficiency in terms of sulphate reduction and metals removal was obtained. Both ethanol and lactate can be used by this inoculum as carbon source. With the other samples tested sulphate reduction was inhibited by the presence of copper and zinc. This highly metal resistant consortium will be used to inoculate a bioreactor to carry out AMD decontamination.


Assuntos
Biodegradação Ambiental , Resíduos Industriais/prevenção & controle , Metais Pesados , Mineração , Bactérias Redutoras de Enxofre/metabolismo , Ácidos , Etanol/metabolismo , Ácido Láctico/metabolismo , Mineração/métodos , Sulfatos/metabolismo , Poluentes Químicos da Água/metabolismo
19.
Curr Pharm Des ; 14(29): 3120-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19075695

RESUMO

Thymbra capitata and Thymus species are commonly known in Portugal as thyme and they are currently used as culinary herbs, as well as for ornamental, aromatizing and traditional medicinal purposes. The present work reports on the state of the art on the information available on the taxonomy, ethnobotany, cell and molecular biology of the Portuguese representatives of these genera and on the chemotaxonomy and antibacterial, antifungal and antioxidant activities of their essential oils and other volatile-containing extracts.


Assuntos
Antifúngicos , Antioxidantes , Óleos Voláteis , Óleos de Plantas , Thymus (Planta) , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Classificação , Etnobotânica , Humanos , Lamiaceae/química , Lamiaceae/classificação , Lamiaceae/crescimento & desenvolvimento , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/farmacologia , Portugal , Thymus (Planta)/química , Thymus (Planta)/crescimento & desenvolvimento
20.
Appl Environ Microbiol ; 74(17): 5451-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18515491

RESUMO

Listeria monocytogenes is a food-borne pathogen capable of adhering to a range of surfaces utilized within the food industry, including stainless steel. The factors required for the attachment of this ubiquitous organism to abiotic surfaces are still relatively unknown. In silico analysis of the L. monocytogenes EGD genome identified a putative cell wall-anchored protein (Lmo0435 [BapL]), which had similarity to proteins involved in biofilm formation by staphylococci. An insertion mutation was constructed in L. monocytogenes to determine the influence of this protein on attachment to abiotic surfaces. The results show that the protein may contribute to the surface adherence of strains that possess BapL, but it is not an essential requirement for all L. monocytogenes strains. Several BapL-negative field isolates demonstrated an ability to adhere to abiotic surfaces equivalent to that of BapL-positive strains. BapL is not required for the virulence of L. monocytogenes in mice.


Assuntos
Aderência Bacteriana , Proteínas de Bactérias/genética , Biofilmes , Listeria monocytogenes/genética , Animais , DNA Bacteriano/genética , Contaminação de Equipamentos , Feminino , Microbiologia de Alimentos , Indústria de Processamento de Alimentos , Genes Bacterianos , Genoma Bacteriano , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/patogenicidade , Listeriose/microbiologia , Camundongos , Mutagênese Insercional , Fases de Leitura Aberta , Plasmídeos , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Especificidade da Espécie
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