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2.
Clin Ter ; 174(1): 23-27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36655640

RESUMO

Introduction: This study aimed to evaluate the antibiofilm effect of different agents (neutral soap, 4% chlorhexidine, Efferdent effervescent tablets, 1% triclosan, and citronella essential oil) used for ocular prosthesis cleaning. Material and Methods: Biofilms of S. aureus and S. epidermidis were formed on 60 ocular prosthesis acrylic resin specimens. The specimens were cleaned with the studied agents with different techniques. Microorganism counting was performed. Data were submitted to ANOVA and HSD Tukey-Kramer (p<.01). Results: When compared to the control group, all cleaning protocols promoted a reduction in growth of microorganisms. The 4% chlorhexidine, effervescent tablets, and 1% triclosan cleaning agents eliminated biofilm in all groups. Conclusion: Therefore, immersion in 4% chlorhexidine, effervescent tablets, and 1% triclosan could be the best protocols indicated for ocular prosthesis cleaning due to their ability to eliminate biofilm.


Assuntos
Clorexidina , Triclosan , Humanos , Clorexidina/farmacologia , Olho Artificial , Staphylococcus aureus , Triclosan/farmacologia , Biofilmes , Comprimidos/farmacologia
3.
Lett Appl Microbiol ; 75(3): 565-577, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34687563

RESUMO

This study aimed to evaluate the inhibitory effects of phenolic-rich extracts from acerola (Malpighia emarginata D.C., PEA), cashew apple (Anacardium occidentale L., PEC) and mango (Mangifera indica L., PEM) by-products on distinct enterotoxigenic Escherichia coli (ETEC) strains. The capability of PEA and PEC of impairing various physiological functions of ETEC strains was investigated with multiparametric flow cytometry. Procyanidin B2 , myricetin and p-coumaric acid were the major phenolic compounds in PEA, PEC and PEM, respectively. PEA and PEC had lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) (MIC: 31·25 mg ml-1 ; MBC: 62·5 mg ml-1 ) on ETEC strains than PEM (MIC and MIC: >1000 mg ml-1 ). PEA and PEC (15·6, 31·2, 62·5 mg ml-1 ) caused viable count reductions (P < 0·05) on ETEC strains after 24 h of exposure, notably the ≥3 log reductions caused by 62·5 mg ml-1 . The 24 h exposure of ETEC strains to PEA and PEC (31·2, 62·5 mg ml-1 ) led to high sizes of cell subpopulations with concomitant impairments in cell membrane polarization and permeability, as well as in enzymatic, respiratory and efflux activities. PEA and PEC are effective in inhibiting ETEC through a multi-target action mode with disturbance in different physiological functions.


Assuntos
Anacardium , Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Mangifera , Fenóis/farmacologia , Extratos Vegetais/farmacologia
4.
Environ Int ; 142: 105830, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32585499

RESUMO

Nowadays ambient particulate matter (PM) levels still regularly exceed the guideline values established by World Health Organization in most urban areas. Numerous experimental studies have already demonstrated the airway toxicity of the fine fraction of PM (FP), mainly triggered by oxidative stress-induced airway inflammation. However, only few studies have actually paid close attention to the ultrafine fraction of PM (UFP), which is likely to be more easily internalized in cells and more biologically reactive. Mitochondria are major endogenous sources of reactive oxygen species (ROS) through oxidative metabolism, and coordinate many critical cellular signaling processes. Mitochondria have been often studied in the context of PM toxicity and generally associated with apoptosis activation. However, little is known about the underlying adaptation mechanisms that could occur following exposure at sub-apoptotic doses of ambient PM. Here, normal human bronchial epithelial BEAS-2B cells were acutely or repeatedly exposed to relatively low doses (5 µg.cm-2) of FP (PM2.5-0.18) or quasi-UFP (Q-UFP; PM0.18) to better access the critical changes in mitochondrial morphology, functions, and dynamics. No significant cytotoxicity nor increase of apoptotic events were reported for any exposure. Mitochondrial membrane potential (ΔΨm) and intracellular ATP content were also not significantly impaired. After cell exposure to sub-apoptotic doses of FP and notably Q-UFP, oxidative phosphorylation was increased as well as mitochondrial mass, resulting in increased production of mitochondrial superoxide anion. Given this oxidative boost, the NRF2-ARE signaling pathway was significantly activated. However, mitochondrial dynamic alterations in favor of accentuated fission process were observed, in particular after Q-UFP vs FP, and repeated vs acute exposure. Taken together, these results supported mitochondrial quality control and metabolism dysfunction as an early lung underlying mechanism of toxicity, thereby leading to accumulation of defective mitochondria and enhanced endogenous ROS generation. Therefore, these features might play a key role in maintaining PM-induced oxidative stress and inflammation within lung cells, which could dramatically contribute to the exacerbation of inflammatory chronic lung diseases. The prospective findings of this work could also offer new insights into the physiopathology of lung toxicity, arguably initiate and/or exacerbate by acutely and rather repeated exposure to ambient FP and mostly Q-UFP.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Células Epiteliais , Humanos , Tamanho da Partícula , Material Particulado/análise , Estudos Prospectivos
5.
Microb Pathog ; 130: 259-270, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30917922

RESUMO

Fruits are among the main natural sources of phenolic compounds (PC). These compounds exert important antioxidant properties primarily associated with the presence of hydroxyl groups in their molecular structure. Additionally, the antibacterial effects of fruit phenolic-rich extracts or individual PC commonly found in fruits have been an emerging research focus in recent years. This review discusses by first time the available literature regarding the inhibitory effects of fruit PC on pathogenic bacteria, including not only their direct effects on bacterial growth and survival, but also their effects on virulence factors and antibiotic resistance, as well as the possible mechanism underlying these inhibitory properties. The results of the retrieved studies show overall that the antibacterial effects of fruit PC vary with the target bacteria, type of PC and length of exposure to these compounds. The type of solvent and procedures used for extraction and fruit cultivar also seem to influence the antibacterial effects of phenolic-rich fruit extracts. Fruit PC have shown wide-spectrum antibacterial properties besides being effective antibiotic resistance modifying agents in pathogenic bacteria and these effects have shown to be associated with interruption of efflux pump expression/function. Furthermore, fruit PC can cause down regulation of a variety of genes associated with virulence features in pathogenic bacteria. Results of available studies indicate the depolarization and alteration of membrane fluidity as mechanisms underlying the inhibition of pathogenic bacteria by fruit PC. These data reveal fruit PC have potential antimicrobial properties, which should be rationally exploited in solutions to control pathogenic bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Frutas/química , Fenóis/farmacologia , Compostos Fitoquímicos/farmacologia , Antibacterianos/isolamento & purificação , Viabilidade Microbiana/efeitos dos fármacos , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Virulência/efeitos dos fármacos
6.
Animal ; 12(10): 2017-2026, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29306351

RESUMO

Goats have played a key role as source of nourishment for humans in their expansion all over the world in long land and sea trips. This has guaranteed a place for this species in the important and rapid episode of livestock expansion triggered by Columbus' arrival in the Americas in the late 1400s. The aims of this study are to provide a comprehensive perspective on genetic diversity in American goat populations and to assess their origins and evolutionary trajectories. This was achieved by combining data from autosomal neutral genetic markers obtained in more than two thousand samples that encompass a wide range of Iberian, African and Creole goat breeds. In general, even though Creole populations differ clearly from each other, they lack a strong geographical pattern of differentiation, such that populations of different admixed ancestry share relatively close locations throughout the large geographical range included in this study. Important Iberian signatures were detected in most Creole populations studied, and many of them, particularly the Cuban Creole, also revealed an important contribution of African breeds. On the other hand, the Brazilian breeds showed a particular genetic structure and were clearly separated from the other Creole populations, with some influence from Cape Verde goats. These results provide a comprehensive characterisation of the present structure of goat genetic diversity, and a dissection of the Iberian and African influences that gave origin to different Creole caprine breeds, disentangling an important part of their evolutionary history. Creole breeds constitute an important reservoir of genetic diversity that justifies the development of appropriate management systems aimed at improving performance without loss of genomic diversity.


Assuntos
Cruzamento , Variação Genética , Cabras , Animais , Brasil , Marcadores Genéticos , Cabras/genética , Filogenia
7.
Braz. j. biol ; 77(1): 132-139, Jan-Mar. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-839158

RESUMO

Abstract Diplopods are considered important macroarthropods the soil as part of its maintenance and balance. These animals usually do not occur in high densities, but population explosions caused by environmental disturbances, climate changes, and use of pesticides that eliminate possible competitors, have been reported. The millipede Urostreptus atrobrunneus Pierozzi and Fontanetti, 2006 have become a nuisance to humans in infestation sites in urban centers of the state of Sao Paulo, Brazil. As a contribution to the understanding of this potential pest, this study describes the histology, histochemistry, and ultrastructure of the U. atrobrunneus midgut, and presents the redefinition of hepatic cells somewhat controversial in the literature. The region of the midgut is characterized by the absence of a cuticular intima, and composed of a pseudostratified epithelium on a thick basal membrane, followed by a muscle layer, a layer of hepatic cells, lined by an external membrane. The morphology observed in U. atrobrunneus is similar to that reported for other species of diplopods. The hepatic cells have been previously described as randomly without forming a layer, however, the present results clearly demonstrate that these cells form a continuous layer over the whole midgut.


Resumo Diplópodos são considerados importantes macro-artrópodes do solo, uma vez que participam de sua manutenção e equilíbrio. Comumente estes animais não apresentam população numerosa, porém há relatos de explosões populacionais ocasionadas por desequilíbrios ambientais, mudanças climáticas e utilização de pesticidas que eliminam possíveis competidores. O milípede Urostreptus atrobrunneus Pierozzi e Fontanetti, 2006, têm apresentado pontos de infestação em centros urbanos, do estado de São Paulo, Brasil, causando muitos transtornos à população humana. Com objetivo de contribuir para o conhecimento desta potencial praga, este trabalho apresenta a descrição histológica, histoquímica e ultra-estrutural do intestino médio do milípede U. atrobrunneus, bem como apresenta a redefinição das células hepáticas, um tanto controversa na literatura pertinente. A região do intestino médio é caracterizada pela ausência da íntima cuticular, sendo formado por um epitélio pseudoestratificado, apoiado por uma membrana basal espessa, seguido de uma camada muscular, uma camada de células hepáticas, revestido por uma membrana externa. A morfologia observada neste trabalho assemelha-se bastante com as descrições de outras espécies de diplópodos estudadas até o momento. As células hepáticas foram previamente descritas como dispostas aleatoriamente sem a formação de uma camada, contudo, os presentes resultados demonstram claramente que estas células formam uma camada contínua ao longo de todo o intestino médio.


Assuntos
Animais , Artrópodes/anatomia & histologia , Hepatócitos/citologia , Trato Gastrointestinal/anatomia & histologia
8.
Braz J Biol ; 0: 0, 2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27409229

RESUMO

Diplopods are considered important macroarthropods the soil as part of its maintenance and balance. These animals usually do not occur in high densities, but population explosions caused by environmental disturbances, climate changes, and use of pesticides that eliminate possible competitors, have been reported. The millipede Urostreptus atrobrunneus Pierozzi and Fontanetti, 2006 have become a nuisance to humans in infestation sites in urban centers of the state of Sao Paulo, Brazil. As a contribution to the understanding of this potential pest, this study describes the histology, histochemistry, and ultrastructure of the U. atrobrunneus midgut, and presents the redefinition of hepatic cells somewhat controversial in the literature. The region of the midgut is characterized by the absence of a cuticular intima, and composed of a pseudostratified epithelium on a thick basal membrane, followed by a muscle layer, a layer of hepatic cells, lined by an external membrane. The morphology observed in U. atrobrunneus is similar to that reported for other species of diplopods. The hepatic cells have been previously described as randomly without forming a layer, however, the present results clearly demonstrate that these cells form a continuous layer over the whole midgut.


Assuntos
Artrópodes/anatomia & histologia , Trato Gastrointestinal/anatomia & histologia , Hepatócitos/citologia , Animais
9.
Genet Mol Res ; 14(4): 18485-93, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26782496

RESUMO

In this study, Lactococcus lactis was engineered to express mutated internalin A on its surface and to secrete large amounts of listeriolysin O (LLO) in order to improve its potential as a vehicle for DNA vaccination. Western blotting experiments demonstrated that the bacterium expressed LLO in both the cytoplasmic and extracellular compartments, with higher quantities found in the culture supernatants. A hemolytic assay showed that the recombinant strain secreted 250 ng active LLO/mg total protein. This mInlA/LLO-producing strain of L. lactis may be used as an alternative tool in DNA vaccination against a number of infectious diseases or in cancer therapy.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Toxinas Bacterianas/genética , Toxinas Bacterianas/imunologia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/imunologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/imunologia , Lactococcus lactis/genética , Listeria monocytogenes/imunologia , Mutação , Proteínas Recombinantes , Vacinas Bacterianas , Membrana Celular/metabolismo , Expressão Gênica , Hemólise , Lactococcus lactis/metabolismo , Vacinação
10.
Clin Genet ; 86(1): 74-84, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23829326

RESUMO

Marinesco-Sjögren syndrome (MSS; MIM 248800) is an autosomal recessive disorder characterized by congenital cerebellar ataxia, early cataracts, developmental delay, myopathy and short stature. Alterations in the gene SIL1 cause MSS in some patients with typical findings. In this study, molecular investigations including sequencing of the SIL1 gene, western blotting and microscopic investigations in fibroblast cultures were carried out in a cohort of 15 patients from 14 unrelated families, including the large, inbred family reported by Superneau et al., having the clinical features of MSS to provide insights into the pathophysiology of the disorder. A total of seven different mutations were found in eight of the patients from seven families. The mutations caused loss of the BIP-associated protein (BAP) protein in four patients by western blot. Novel clinical features such as dental abnormalities, iris coloboma, eczema and hormonal abnormalities were noticed in some patients, but there was no clear way to distinguish those with and without SIL1 mutations. Cultured fibroblasts contained numerous cytoplasmic inclusion bodies, similar to those identified in the brain of the whoozy mouse in five unrelated patients, three with and two without SIL1 mutations, suggesting some SIL1 negative patients share a common cellular pathogenesis with those who are SIL1 positive.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Fenótipo , Degenerações Espinocerebelares/genética , Degenerações Espinocerebelares/fisiopatologia , Sequência de Bases , Western Blotting , Pré-Escolar , Primers do DNA/genética , Feminino , Genótipo , Humanos , Lactente , Masculino , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Mutação/genética , Análise de Sequência de DNA
11.
J Anim Breed Genet ; 129(1): 79-87, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22225587

RESUMO

Brazilian goat breeds are believed to derive mainly from animals brought by Portuguese settlers since the 16th century. We used microsatellite markers in a sample of 436 animals to study genetic variability and differentiation of the six Portuguese (PT) and six Brazilian (BR) goat breeds currently recognized in the two countries. These breeds were also compared with an outgroup represented by a sample of Alpine (ALP) goats. The effective number of alleles and allelic richness were slightly higher in PT than in BR breeds. The global F(ST) was nearly 0.11 when PT and BR breeds were considered, with a mean pairwise F(ST) of about 0.03 among PT breeds, 0.07 among BR breeds and 0.15 between PT and BR breeds. The dendrogram illustrating relationships between populations and the correspondence analysis indicate the existence of two very distinct clusters, corresponding to the countries of origin of the breeds studied, which are nearly equidistant from the Alpine outgroup. The analysis with structure confirmed the separation between PT and BR breeds but suggests that some BR breeds, especially Graúna and Canindé, may share a common ancestry with PT breeds. The divergence observed between PT and BR breeds may result from founder effects and genetic drift but could also reflect the introduction in Brazil of goats originating from other regions, e.g., West Africa.


Assuntos
Deriva Genética , Cabras/genética , Animais , Oceano Atlântico , Brasil , Frequência do Gene , Loci Gênicos/genética , Variação Genética , Heterozigoto , Repetições de Microssatélites/genética , Portugal
12.
J Fr Ophtalmol ; 33(7): 465-71, 2010 Sep.
Artigo em Francês | MEDLINE | ID: mdl-20579769

RESUMO

PURPOSE: To assess limbal epithelial cell growth kinetics in vitro using tissue retrieved from organ-cultured donor corneas. PATIENTS AND METHODS: Twenty-one limbal explants were retrieved from corneoscleral rims of donor corneal grafts preserved for 18-24 days in organ culture. The explants were cultured at 37°C for 10, 13, or 18 days. The epithelial cell sheet area was measured during culture by means of morphometry. At the end of culture, the dissociated cells were counted and analyzed by immunocytochemistry. RESULTS: The curve of the epithelial cell sheet area (S) in relation to culture time (t) was best fitted by a polynomial model (S=0.024t(3) - 0.038t(2) - 0.044t + 0.092). The average duration of the cell cycle was 24h. Cell growth decreased as donor tissue retrieval postmortem time increased. Cultured cells featured various expressions of cytokeratin-3 ranging from absent (few cells) to strong. More than 50% of cells expressed vimentin. CONCLUSION: Limbal tissue retrieved from donor tissue that was organ-cultured for 3 weeks maintains a potential for cell renewal and growth compatible with clinical use for limbal allograft transplantation or cultured stem cell transplantation. However, cell growth potential is impaired by donor postmortem ischemia, which implies that tissue must be retrieved as soon as possible after donor death.


Assuntos
Proliferação de Células , Limbo da Córnea/citologia , Células Cultivadas , Células Epiteliais , Humanos
13.
Vaccine ; 28(3): 597-603, 2010 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19800443

RESUMO

Leishmune, the first licensed vaccine for prophylaxis against canine visceral leishmaniasis (CVL) and is also immunotherapeutic when used with double saponin adjuvant concentration. The Leishmune therapeutic vaccine was assessed for immunotherapy (IT) in 31 infected dogs and for immunochemotherapy (ICT) in combination with allopurinol or amphotericinB/allopurinol, in 35 dogs. Compared to infected untreated control dogs, at month 3, both treatments increased the proportion of dogs showing intradermal response to Leishmania antigen to a similar extent (from 8 to 67%, in the IT and to 76%, in the ICT groups), and conversely reduced from 100 to 38% (IT) and to 18% (ICT) the proportion of symptomatic cases, from 54 to 12% (IT) and to 15% (ICT) the proportion of parasite evidence in lymph nodes and from 48 to 19% (IT) and 12% (ICT) the proportion of deaths, indicating that the immunotherapy with enriched-Leishmune vaccine promotes the control of the clinical and parasitological signs of CVL rendering most dogs asymptomatic although PCR positive. By month 8, negative lymph node PCR results were obtained in 80% of the ICT-treated dogs, but only in 33% of the IT group (p=0.0253), suggesting that the combination of additional chemotherapy with Leishmune-enriched saponin vaccination abolished, not only the symptoms but also the latent infection condition, curing the dogs. The animals were followed up until 4.5 years after the beginning of the experiment and, compared to the untreated control group at month 3 (12/25 dogs; 48%), a decrease in the rate of CVL deaths was only seen after ICT treatment (7/35 dogs; 20%; 0.0273) but not after IT treatment (10/31 dogs; 32%; p=0.278), pointing out an additional advantage of the ICT treatment with the enriched-Leishmune in the control and cure of CVL.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Doenças do Cão/terapia , Tratamento Farmacológico/métodos , Imunoterapia/métodos , Leishmaniose Visceral/veterinária , Vacinas Protozoárias/uso terapêutico , Saponinas/uso terapêutico , Alopurinol/uso terapêutico , Anfotericina B/uso terapêutico , Animais , Antiprotozoários , Doenças do Cão/patologia , Cães , Quimioterapia Combinada , Seguimentos , Leishmaniose Visceral/patologia , Leishmaniose Visceral/terapia , Linfonodos/parasitologia , Análise de Sobrevida , Resultado do Tratamento
14.
Procedia Vaccinol ; 1(1): 104-109, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-32288909

RESUMO

The Nucleoside Hydrolase (NH36) is the main marker of the FML complex of Leishmania donovani, antigen of the licensed Leishmune® vaccine for prophylaxis of canine visceral leishmaniasis. As a DNA vaccine in mice, it induces a TH1 immune response. We vaccinated mongrel dogs with the VR1012NH36 vaccine for prophylaxis and immunotherapy against a high dose Leishmania chagasi infection (7 x 108 infective amastigotes). The untreated controls developed more symptoms, higher parasite/lymphocyte ratio, smaller DTH reactions, lower proportions of NH36-specific CD4+ cells and sustained NH36-specific CD8+ cell counts than dogs of the prophylaxis group. In the immunotherapy treated group, enlarged DTH reactions, enhanced CD4+ and sustained CD8+ lymphocyte proportions were also detected, however, without reduction of symptoms or parasite/lymphocyte ratio, indicating that the vaccine was sufficiently potent to prevent but not to control the disease. Both treatments determined higher survival rates. Anti-FML antibodies increased in vaccinated and control dogs while anti-NH36 antibodies were only increased in vaccinees (p= 0.000). The parasite load of an untreated survivor control dog (638.05 parasites) felt outside the IC95% of that of vaccinated dogs (32.02, IC95% 9.45-64.59) suggesting that both vaccination treatments succeeded in reducing the Leishmania infective burden. Accordingly, an untreated control dog showed lower levels of IFN γ-ß, IL-2, IL4 but not IL-10 ß actin-relative quantification. We conclude that the VR1012-NH36 vaccine induces strong prophylactic protection and a milder immunotherapeutic effect against a high dose canine experimental infection with Leishmania chagasi.

15.
Vaccine ; 26(39): 4991-7, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18675868

RESUMO

Leishmune is the industrialized version of the FML-saponin vaccine which has been shown to develop 92-95% protection in vaccinated dogs and 76-80% vaccine efficacy against field canine visceral leishmaniasis (CVL) in Brazil. Leishmune has been proven to be safe and tolerable and a transmission-blocking vaccine which renders vaccinated dogs non-infectious to sand fly vectors. In the present investigation, 550 healthy seronegative dogs of endemic and epidemic areas of Brazil were monitored for Leishmune-induced immunogenicity during a 2-year trial. Another group of 588 untreated exposed dogs was also studied in parallel. Both groups were seronegative on day 0. The strong immunogenicity induced by Leishmune vaccine was demonstrated by the 98% of FML-seroconversion, increase in absorbencies, the 82.7% DTH positive reactions and increase in skin test size diameters, the average increase in CD8+ total lymphocytes population in blood (27.1%), expected for QS21 saponin-containing vaccine, the sustained proportions of CD4+ T cells, and the average increased proportions of CD21+ B lymphocytes (42.3%). The Leishmune-induced protection against CVL is demonstrated by the results: 98.8% asymptomatic dogs (at the end of first year) and 99% healthy survivors (at the end of the second year) among vaccinated dogs, compared to the 79.4% asymptomatic and 61% survivor dogs (p<0.001) monitored in the untreated exposed cohort. In spite of the low vaccine coverage, it was possible to detect a 66.1% (p<0.005) reduction in Belo Horizonte and an 80.2% (p<0.005) reduction in Araçatuba of the incidence of CVL among vaccinated dogs, when compared to the global incidence of CVL of each town, respectively. Our preliminary results support the potential use of Leishmune to prevent CVL epidemics.


Assuntos
Doenças do Cão/imunologia , Leishmania donovani/imunologia , Vacinas contra Leishmaniose/imunologia , Leishmaniose Visceral/veterinária , Adjuvantes Imunológicos/farmacologia , Animais , Antígenos de Protozoários/imunologia , Brasil , Doenças do Cão/parasitologia , Doenças do Cão/prevenção & controle , Cães , Citometria de Fluxo , Hipersensibilidade Tardia/imunologia , Hipersensibilidade Tardia/parasitologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/prevenção & controle , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/parasitologia , Saponinas/imunologia , Saponinas/farmacologia
16.
Br J Pharmacol ; 154(6): 1216-24, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18516074

RESUMO

BACKGROUND AND PURPOSE: Oncocalyxone A (OncoA) has a concentration-dependent anti-platelet activity. The present study aimed to further understand the mechanisms related to this effect. EXPERIMENTAL APPROACH: Human platelet aggregation was measured by means of a turbidimetric method. OncoA (32-256 microM) was tested against several platelet-aggregating agents, such as adenosine diphosphate (ADP), collagen, arachidonic acid (AA), ristocetin and thrombin. KEY RESULTS: OncoA completely inhibited platelet aggregation with a calculated mean inhibitory concentration (IC50-microM) of 122 for ADP, 161 for collagen, 159 for AA, 169 for ristocetin and 85 for thrombin. The anti-aggregatory activity of OncoA was not inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). OncoA, at a concentration that caused no significant anti-aggregatory activity, potentiated sodium nitroprusside (SNP) anti-aggregatory activity (18.8+/-2.9%-SNP vs 85.0+/-8.2%-SNP+OncoA). The levels of nitric oxide (NO) or cAMP were not altered by OncoA while cGMP levels were increased more than 10-fold by OncoA in resting or ADP-activated platelets. Flow cytometry revealed that OncoA does not interact with receptors for fibrinogen, collagen or P-selectin. Nevertheless, OncoA decreased the binding of antibodies to GP Ibalpha, a glycoprotein that is related both to von Willebrand factor and to thrombin-induced platelet aggregation. CONCLUSION AND IMPLICATIONS: OncoA showed anti-aggregatory activity in platelets that was associated with increased cGMP levels, not dependent on NO and with blocking GP Ibalpha glycoprotein. This new mechanism has the prospect of leading to new anti-thrombotic drugs.


Assuntos
Antraquinonas/farmacologia , AMP Cíclico/biossíntese , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Difosfato de Adenosina/farmacologia , Trifosfato de Adenosina/metabolismo , Adolescente , Adulto , Antraquinonas/isolamento & purificação , Antraquinonas/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , AMP Cíclico/sangue , GMP Cíclico/sangue , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/sangue , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Feminino , Citometria de Fluxo , Guanilato Ciclase/sangue , Guanilato Ciclase/metabolismo , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Inibidores da Agregação Plaquetária/metabolismo , Ligação Proteica , Tromboxano A2/fisiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-18243822

RESUMO

The comparison of two methods based on online solid phase extraction-liquid chromatography with UV (SPE-LC-UV) or mass spectrometry detection (SPE-LC-MS/MS) for the simultaneous quantification of sulfamethoxazole (SMZ) and trimethoprim (TMP) is presented. The methods were validated and proved to be accurate. The analysis of standard samples for SMZ at concentrations of 0.5, 1.5, 25 and 50microg/mL demonstrated a relative standard deviation of less than 6% for both methods (n=18), while TMP samples at concentrations of 0.05, 0.15, 1.5 and 5.0microg/mL were analyzed with R.S.D. of less than 4% (n=18). The method with mass spectrometric detection was approximately six times more sensitive than the method with ultraviolet detection. The total run time for the SPE-LC-MS/MS was 2.5min per sample as opposed to 18.0min for the SPE-LC-UV method. The method with MS detection in comparison with UV detection proved to be more rugged and was successfully applied to pharmacokinetics studies.


Assuntos
Anti-Infecciosos/análise , Combinação Trimetoprima e Sulfametoxazol/análise , Adolescente , Adulto , Anti-Infecciosos/farmacocinética , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Feminino , Humanos , Indicadores e Reagentes , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Espectrometria de Massas em Tandem , Equivalência Terapêutica , Combinação Trimetoprima e Sulfametoxazol/farmacocinética
18.
Vaccine ; 25(33): 6176-90, 2007 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-17630055

RESUMO

In order to assess the immunotherapeutic potential on canine visceral leishmaniasis of the Leishmune vaccine, formulated with an increased adjuvant concentration (1mg of saponin rather than 0.5mg), 24 mongrel dogs were infected with Leishmania (L.) chagasi. The enriched-Leishmune vaccine was injected on month 6, 7 and 8 after infection, when animals were seropositive and symptomatic. The control group were injected with a saline solution. Leishmune-treated dogs showed significantly higher levels of anti-FML IgG antibodies (ANOVA; p<0.0001), a higher and stable IgG2 and a decreasing IgG1 response, pointing to a TH1 T cell mediated response. The vaccine had the following effects: it led to more positive delayed type hypersensitivity reactions against Leishmania lysate in vaccinated dogs (75%) than in controls (50%), to a decreased average of CD4+ Leishmania-specific lymphocytes in saline controls (32.13%) that fell outside the 95% confidence interval of the vaccinees (41.62%, CI95% 43.93-49.80) and an increased average of the clinical scores from the saline controls (17.83) that falls outside the 95% confidence interval for the Leishmune immunotherapy-treated dogs (15.75, CI95% 13.97-17.53). All dogs that received the vaccine were clustered, and showed lower clinical scores and normal CD4+ counts, whereas 42% of the untreated dogs showed very diminished CD4+ and higher clinical score. The increase in clinical signs of the saline treated group was correlated with an increase in anti-FML antibodies (p<0.0001), the parasitological evidence (p=0.038) and a decrease in Leishmania-specific CD4+ lymphocyte proportions (p=0.035). These results confirm the immunotherapeutic potential of the enriched-Leishmune vaccine. The vaccine reduced the clinical symptoms and evidence of parasite, modulating the outcome of the infection and the dog's potential infectiosity to phlebotomines. The enriched-Leishmune vaccine was subjected to a safety analysis and found to be well tolerated and safe.


Assuntos
Leishmaniose Visceral/imunologia , Leishmaniose Visceral/terapia , Vacinas Protozoárias/imunologia , Saponinas/química , Animais , DNA de Protozoário , Cães , Imunoglobulina G/sangue , Imunoterapia , Fatores de Tempo
19.
Vaccine ; 25(12): 2180-6, 2007 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-17239495

RESUMO

A group of 600 healthy and asymptomatic dogs from Brazilian canine visceral leishmaniasis endemic areas was vaccinated with three sc doses of Leishmune which is the industrialized formulation of the FML-saponin, recently licensed for commercialization in Brazil, which previously showed 76-80% vaccine efficacy against canine visceral leishmaniasis. Safety evaluation was performed for 14 days after each vaccine injection and disclosed transient reactions of local pain (40.87%), anorexia (20.48%), apathy (24.17%), local swelling reactions (15.90%), vomit (2.4%) and diarrhoea (1.5%). All effects showed significantly correlating declines, from the first to the third dose (p<0.0001). Most of the noticed reactions of pain (73%), anorexia (79%) and local swelling (84.7%) were mild. No significant differences between puppies and adults dogs were found in the number of adverse reactions. Adult dogs developed however, 94.5% of the small swelling reactions (<3 cm), and indicating that they are more resistant to the inflammatory response promoted by the saponins. No dead by anaphylaxis occurred, and only two dogs (0.1%) showed allergic reactions (facial oedema and itching) after the third dose. Transient alopecia on injection site occurred in only five poodles (0.28%) with total recovery and no need of treatment. All the mild adverse events in response to Leishmune injection were transient and disappeared before the injection of the following vaccine dose, confirming the tolerability of the vaccine. The Leishmune preparation was less haemolytic (HD(50)=180 microg/ml) than expected for a QS21 saponin-containing vaccine, indicating that its formulation with the FML antigen diminished the potential in vitro toxicity.


Assuntos
Doenças do Cão/imunologia , Leishmania donovani/imunologia , Leishmaniose Visceral/veterinária , Vacinas Protozoárias/imunologia , Animais , Brasil , Doenças do Cão/parasitologia , Doenças do Cão/prevenção & controle , Cães , Edema/induzido quimicamente , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/prevenção & controle , Vacinas Protozoárias/administração & dosagem , Vacinas Protozoárias/efeitos adversos , Prurido/induzido quimicamente , Fatores de Tempo , Resultado do Tratamento
20.
Vaccine ; 25(4): 649-58, 2007 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-17014936

RESUMO

The CP05 saponin from Calliandra pulcherrima Benth, shows remarkable similarities to the QS21 saponin of Quillaja saponaria Molina. Both shared a monoterpene hydrophobic moiety, a glycidic chain attached to the triterpene C28, and three sugars attached to C3. Different from QS21, the CP05 does not show the aldehyde group in triterpene C4 involved in TH1 response. Balb/c mice were immunized either intact saponin (CP05), the monoterpene-deprived (BS), the C28 carbohydrate-deprived (HS) or the sapogenin fraction, in formulation with the FML antigen of Leishmania donovani and challenged with 2 x 10(8) amastigotes of L. chagasi. While the CP05 induced 90% survival and 92.1% parasite reduction, a 100% survival and 94.1% protection were detected after the BS-vaccine treatment, indicating that the monoterpene acylated moiety, absent in the BS vaccine, is not necessary for the induction of a protective global TH1 response. Only the DTH response of BS vaccines was mildly lower than that of CP05 vaccinees. Maximal anti-FML antibody, CD4(+) and CD8(+) Leishmania specific lymphocytes, IFN-gamma splenocyte secretion, reduction in parasite load and survival was also detected for the BS vaccine. The HSFML vaccine showed diminished responses in all tested variables, except for IFN-gamma secretion, indicating that the integrity of the carbohydrate moiety attached to C28 is mandatory for the these functions. No protection was induced by the sapogenin-FML indicating that the CP05 triterpene which lacks the C4 aldehyde group, is not a immunostimulating compound. No contribution to protection was detected in the CP05 saponin treated control group supporting the specificity of the FML antigenic preparation.


Assuntos
Fabaceae/química , Leishmaniose Visceral/prevenção & controle , Saponinas/química , Saponinas/farmacologia , Terpenos/química , Adjuvantes Imunológicos , Animais , Feminino , Imunoglobulinas/sangue , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , Vacinação
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