Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 177
Filtrar
1.
Br Poult Sci ; : 1-9, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212222

RESUMO

1. The purpose of this meta-analysis was to evaluate the effect of mannan oligosaccharide (MOS) as an alternative to antibiotic growth promoters (AGP) on feed intake (FI), body weight gain (BWG), and feed conversion ratio (FCR) of broilers.2. Data from 75,594 broilers were extracted from 17 articles (19 trials) published between January 2010 and March 2023. The main criteria for the publication selection were as follows, at least three treatments applied (negative control group without MOS or AGP versus MOS or AGP supplementation), presence of performance results, and intra-experimental variation associated with the mean of response (such as standard error). Treatments were classified as control, MOS, or AGP, and adjusted means of treatment were compared. Additionally, the average daily gain (ADG) and average daily feed intake (ADFI) of each type of supplementation were calculated relative (Δ) to the control group (ΔADFI and ΔADG) and expressed as a percentage of the difference.3. Broilers receiving a diet supplemented with MOS had a 3.7% better BWG and 3% better FCR compared to the control diet (P < 0.001), but these variables were similar to the group receiving AGP supplementation. No significant difference was detected in FI among treatments (P > 0.050). The relationship between ΔADG and ΔADFI was linear for the MOS and AGP-supplemented group (P < 0.050). The ΔADG of broilers fed diets supplemented with MOS or AGP was 6.4% and 4.54% when ΔADFI was zero, respectively. The ΔADG of MOS increased by 0.58% for every 1% of increasing observed in ΔADFI. The corresponding value for the increased ΔADG for the AGP group was 0.69%.4. The results of this meta-analysis indicated that MOS supplementation is effective in increasing BWG and reducing FCR, similar to broilers fed a diet supplemented with AGP. Therefore, MOS is a safe and sustainable alternative for AGP-free poultry production.

2.
J Helminthol ; 94: e160, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32478649

RESUMO

The aim of this study was to evaluate the combined use of different chemical (albendazole, ivermectin, glycerine and Vaseline) and biological (Monacrosporium thaumasium) compounds in the control of Ancylostoma caninum. Infective larvae of A. caninum were obtained from coprocultures of positive faeces from naturally infected dogs. We used 1% ivermectin, 1% albendazole, 100% glycerine, 100% Vaseline and an isolate of the nematophagous fungus M. thaumasium (NF34), alone or in combinations. Next, an experimental test was set up with 16 groups in microtubes, with a 24-h interaction. The groups (G1 to G15) that contained any chemical or biological compound (NF34) and/or their combined use (chemical + biological) showed a difference in relation to the control group, except G5 - Vaseline 100% without combinations. It was concluded that, even on an experimental basis, the combined use of anthelmintic drugs with biological control was efficient; however, more studies must be carried out in order to elucidate the synergistic action between chemical and biological compounds to be used in the effective control of hookworms in the future.


Assuntos
Ancylostomatoidea/efeitos dos fármacos , Anti-Helmínticos/farmacologia , Produtos Biológicos/farmacologia , Doenças do Cão/tratamento farmacológico , Infecções por Uncinaria/veterinária , Animais , Ascomicetos , Produtos Biológicos/química , Doenças do Cão/parasitologia , Cães , Sinergismo Farmacológico , Infecções por Uncinaria/tratamento farmacológico , Larva/efeitos dos fármacos
3.
Cytokine ; 99: 163-172, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28917991

RESUMO

Accumulating evidence indicates that the exposure to Mycobacterium bovis bacillus Calmette-Guérin (BCG) prevents the development of allergy and the airway dendritic cells (DCs) may be involved in this protective effect. However, studies to better characterize the specific interactions between BCG and DCs and their role in this mycobacteria-mediated Th2 cell suppression are still ongoing. This study aimed to evaluate the effect of the neonatal BCG vaccination in the innate immune response in a mouse model of ovalbumin (OVA)-induced airway inflammation. BCG treated neonatal BALB/c mice were sensitized and challenged with aerosolized OVA. Twenty-four hours after the last challenge, samples were collected for analysis. The intranasal BCG treatment inhibited the allergic Th2-response by decreasing the allergen-induced eosinophilic inflammation, EPO activity, CCL11, IL-25, TSLP, IL-4 and IL-5 lung levels, and serum levels of IgE. Mycobacteria treatment increased lung levels of IL-10 and TGF-ß, and the TLR2 and TLR4 expressions by pulmonary CD11c+CD103+CD8α+ DCs. Additionally an enhanced expression of PD-L1 was observed besides an increased production of IFN-γ by these cells. These results indicated that neonatal BCG vaccination inhibits key features of allergic airway inflammation, probably by promoting T regulatory immune response via an enhanced expression of TLR2, TLR4 and PD-L1 on DCs.


Assuntos
Antígeno B7-H1/metabolismo , Células Dendríticas/metabolismo , Interferon gama/metabolismo , Mycobacterium bovis/imunologia , Células Th2/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Citocinas/metabolismo , Células Epiteliais/metabolismo , Pulmão/patologia , Camundongos Endogâmicos BALB C , Ovalbumina/metabolismo , Pneumonia/imunologia , Pneumonia/patologia , Linfócitos T Reguladores/metabolismo , Receptores Toll-Like/metabolismo , Regulação para Cima , Vacinação
4.
Lupus ; 25(4): 355-63, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26405022

RESUMO

The clinical expression of systemic lupus erythematosus (SLE) is influenced by genetic and environmental factors and therefore varies between ethnicities. Information on the epidemiology of SLE in Brazil is scarce and practically limited to studies conducted in socioeconomically developed regions (South and Southeast). The objective of this study was to describe the clinical and immunological aspects and outcome of a cohort of patients with SLE treated at a university hospital in northeastern Brazil and compare patterns related to age at onset: childhood (cSLE), adult (aSLE), and late (lSLE). A random sample of 414 records (women: 93.5%) were reviewed. The mean age at SLE onset and the mean disease duration were 28.9 ± 10.9 years and 10.2 ± 6.6 years, respectively. Most patients had aSLE (n = 338; 81.6%), followed by cSLE (n = 60; 14.5%) and lSLE (n = 16; 3.9%). The female/male ratio was 6.5:1 in cSLE and 16.8:1 in aSLE; in lSLE, all patients were female (p = 0.05). During follow-up, the cSLE group presented higher rates of nephritis (70% vs. 52.9% vs. 12.5%; p = 0.0001) and leuko/lymphopenia (61.7% vs. 43.8% vs. 56.2%; p = 0.02). No significant differences were found for anti-dsDNA, anti-Sm, and antiphospholipid antibodies. Treatment with immunosuppressants was significantly more common, and higher doses of prednisone were used, in cSLE. The prevalence of cardiovascular diseases were more frequent in lSLE (p = 0.03). No significant differences were found between the three groups with regard to mean damage accrual (SDI), remission, and mortality. Although cSLE presented higher rates of nephritis and leuko/lymphopenia, more frequent use of immunosuppressants and higher prednisone doses than aSLE and lSLE, the three groups did not differ significantly with regard to damage accrual, remission, and mortality.


Assuntos
Lúpus Eritematoso Sistêmico/imunologia , Nefrite Lúpica/imunologia , Adolescente , Adulto , Idade de Início , Anticorpos Antinucleares/sangue , Anticorpos Antifosfolipídeos/sangue , Biomarcadores/sangue , Brasil/epidemiologia , Criança , Pré-Escolar , Comorbidade , Progressão da Doença , Feminino , Glucocorticoides/uso terapêutico , Hospitais Universitários , Humanos , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/mortalidade , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/mortalidade , Masculino , Pessoa de Meia-Idade , Prevalência , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
5.
J Appl Microbiol ; 121(6): 1519-1529, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27566664

RESUMO

AIMS: To investigate the anti-HSV and anti-inflammatory effects of a standardized ethyl acetate extract (SEAE) prepared with the stem bark of Strychnos pseudoquina, along with two isolated compounds: quercetin 3-O-methyl ether (3MQ) and strychnobiflavone (SBF). METHODS AND RESULTS: The mechanisms of action were evaluated by different methodological strategies. SEAE and SBF affected the early stages of viral infection and reduced HSV-1 protein expression. Both flavonoids elicited a concentration-dependent inhibition of monocyte chemoattractant protein-1 (MCP-1), whereas 3MQ reduced the chemokine release more significantly than SBF. Conversely, both compounds stimulated the production of the cytokines TNF-α and IL-1-ß in LPS-stimulated cells, especially at the intermediate and the highest tested concentrations. CONCLUSIONS: SEAE and SBF interfered with various steps of HSV replication cycle, mainly adsorption, postadsorption and penetration, as well as with ß and γ viral proteins expression; moreover, a direct inactivation of viral particles was observed. Besides, both flavonoids inhibited MCP-1 selectively, a feature that may be beneficial for the development of new anti-HSV agents. SIGNIFICANCE AND IMPACT OF THE STUDY: The results indicated that the samples present anti-HSV and anti-inflammatory activities, at different levels, which is an interesting feature since cold and genital sores are accompanied by an inflammation process.


Assuntos
Antivirais/farmacologia , Biflavonoides/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Quercetina/análogos & derivados , Strychnos/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antivirais/química , Biflavonoides/química , Brasil , Linhagem Celular , Quimiocina CCL2/metabolismo , Chlorocebus aethiops , Citocinas/metabolismo , Herpesvirus Humano 1/fisiologia , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Quercetina/química , Quercetina/farmacologia , Células Vero
6.
Mycopathologia ; 181(11-12): 915-920, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27364896

RESUMO

Paracoccidioidomycosis (PCM) is the most important systemic mycoses in Latin America. We describe a severe case of paracoccidioidomycosis in a 14-year-old boy, with a rapid disease progression. The fungal strain was isolated and inoculated into a T and/or B cell immunocompromised mice, which revealed a highly virulent strain. The case report presented herein emphasizes the importance of considering PCM in the differential diagnosis of patients with other infectious diseases in endemic areas and highlights a novel isolate.


Assuntos
Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/diagnóstico , Paracoccidioidomicose/patologia , Adolescente , Experimentação Animal , Animais , Brasil , Histocitoquímica , Humanos , Hospedeiro Imunocomprometido , Linfonodos/patologia , Masculino , Camundongos , Microscopia , Paracoccidioides/patogenicidade , Paracoccidioidomicose/microbiologia , Análise de Sobrevida
7.
J Helminthol ; 89(2): 244-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24622279

RESUMO

A mycelial formulation in sodium alginate pellets of the nematophagous fungus Monacrosporium thaumasium (isolate NF34A) was assessed in the biological control of beef cattle trichostrongyles in tropical Brazil. Two groups of ten male Nellore calves aged 6 months, a fungus-treated group and a control group, were fed on a pasture of Brachiaria decumbens naturally infected with larvae of cattle trichostrongyles. The fungus-treated group received doses of sodium alginate mycelial pellets orally (1 g pellets (0.2 g fungus)/10 kg live weight) twice a week for 12 months. At the end of the study there was a significant reduction (P< 0.01) in the number of eggs per gram of faeces and coprocultures of the fungus-treated group--47.8% and 50.2%, respectively--in relation to the control group. There was a 47.3% reduction in herbage samples, collected up to 0-20 cm from faecal pats, between the fungus-treated and control groups, and a 58% reduction when the sampling distance was 20-40 cm from faecal pats (P< 0.01). The treatment with sodium alginate pellets containing the nematode-trapping fungus M. thaumasium reduced trichostrongyles in tropical south-eastern Brazil and could be an effective tool for the biological control of this parasitic nematode in beef cattle. However, in such a tropical climate with low rainfall the fungal viability can be reduced.


Assuntos
Ascomicetos/fisiologia , Doenças dos Bovinos/parasitologia , Nematoides/microbiologia , Infecções por Nematoides/veterinária , Controle Biológico de Vetores/métodos , Animais , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Terapia Biológica , Brasil , Bovinos , Doenças dos Bovinos/terapia , Masculino , Nematoides/fisiologia , Infecções por Nematoides/parasitologia , Infecções por Nematoides/terapia
8.
Parasitol Res ; 112(6): 2131-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23494156

RESUMO

Biological control with the use of nematophagous fungi has been described very successfully by many authors and presents itself as a complementary control method, acting on the free-living forms of helminths. The efficacy of a formulation containing the fungus Pochonia chlamydosporia in controlling Fasciola hepatica eggs in faeces was evaluated in an experimental field assay. Two bovine groups (six animals each) were used: A (control) and B (treated with fungus). At 30 days after deworming, the animals were separated into two similar paddocks with flooded areas and were given pellets containing 25 % mycelial mass (group B) or no fungus (group A) at a dose of 1 g/10 kg body weight, twice a week, during 18 months. Faecal samples were harvested fortnightly in the animals of groups A and B and they were submitted at examination of quantitative sedimentation. The mean count of F. hepatica eggs per grams of faeces was significantly higher in group A (1.19) compared with those from group B (0.82) (P < 0.01). After 18 months, animals from group B had gained 42.33 kg above (17.82 % more by weight) (P < 0.01), compared with the control group (A). Every month, faecal samples from paddocks A and B were collected and they were incubated. P. chlamydosporia was identified only in sample source of the paddock B. It can be concluded that the application of this fungical formulation with P. chlamydosporia 25 % mycelial mass was effective in reducing the availability of eggs in the environment and reinfections in calves in natural conditions.


Assuntos
Terapia Biológica/métodos , Doenças dos Bovinos/prevenção & controle , Fasciola hepatica/crescimento & desenvolvimento , Fasciolíase/veterinária , Hypocreales/crescimento & desenvolvimento , Interações Microbianas , Animais , Brasil , Bovinos , Doenças dos Bovinos/parasitologia , Fasciola hepatica/isolamento & purificação , Fasciolíase/prevenção & controle , Fezes/parasitologia , Contagem de Ovos de Parasitas , Resultado do Tratamento
9.
Exp Parasitol ; 132(3): 373-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22975475

RESUMO

The efficacy of a fungal formulation based on the nematophagous fungus Duddingtonia flagrans was assessed in the control of cattle trichostrongyles. Twenty male Nellore calves, six-month-old, divided in two groups (fungus-treated and control without fungus) were fed on a pasture of Brachiaria decumbens naturally infected with larvae of bovine trichostrongyles. Animals of the treated group received doses of sodium alginate mycelial pellets orally (1 g/10 kg live weight, twice a week), for 12 months. Feces samples were collected for egg count (eggs per gram of feces-EPG) and coprocultures during 12 months. There was a significant reduction in EPG (56.7%) and infective larvae (L3) in coprocultures (60.5%) for animals of the treated group in relation to the control group at the end of the study. There was a significant reduction of L3 (64.5%) in herbage samples collected up to 0-20 cm from fecal pats and 73.2% in distant samples (20-40 cm) between the fungus-treated group and the control group. The treatment with sodium alginate pellets containing the nematode trapping fungus D. flagrans reduced trichostrongylid in tropical southeastern Brazil and could be an effective tool for biological control of this parasitic nematode in beef cattle.


Assuntos
Doenças dos Bovinos/prevenção & controle , Duddingtonia/fisiologia , Controle Biológico de Vetores/métodos , Trichostrongyloidea/microbiologia , Tricostrongiloidíase/veterinária , Animais , Brasil , Bovinos , Doenças dos Bovinos/parasitologia , Fezes/parasitologia , Masculino , Contagem de Ovos de Parasitas/veterinária , Poaceae/parasitologia , Estações do Ano , Tricostrongiloidíase/prevenção & controle , Clima Tropical
10.
J Helminthol ; 86(3): 348-52, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21838959

RESUMO

The present study aimed to evaluate the ovicidal activity (type 3 effect) of VC1 and VC4 isolates of Pochonia chlamydosporia in a solid medium and the action of a crude extract of P. chlamydosporia against eggs of Ascaridia galli. To evaluate ovicidal activity in culture medium, 1000 A. galli eggs were plated on Petri dishes containing 2% water-agar with grown fungal isolates (VC1 or VC4) and without fungus (control group) and were examined at 1, 3 and 5 days post-inoculation (assay A). Then, to test the action of crude extracts of P. chlamydosporia (VC1 or VC4), 500 eggs of A. galli were plated on Petri dishes of 4.5 cm diameter with 5 ml of fungal filtrate from each tested isolate. The control group consisted of 500 eggs of A. galli with 10 ml of distilled water on each Petri dish (assay B). Fungal isolates were effective (P < 0.01) at destroying these eggs, showing a type 3 effect at the studied intervals. On the other hand, the crude extract of isolates (VC1 or VC4) reduced the number of A. galli eggs in the treated group compared with the control group by 64.1% and 56.5%, respectively. The results of the present study show that P. chlamydosporia is effective at destroying eggs of A. galli and could therefore be used in the biological control of nematodes.


Assuntos
Ascaridia/efeitos dos fármacos , Ascaridíase/veterinária , Misturas Complexas/farmacologia , Hypocreales/química , Doenças das Aves Domésticas/parasitologia , Animais , Ascaridia/crescimento & desenvolvimento , Ascaridia/microbiologia , Ascaridíase/microbiologia , Contagem de Ovos de Parasitas , Controle Biológico de Vetores/métodos
11.
J Helminthol ; 85(2): 138-41, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20663244

RESUMO

The objective of this work was to evaluate the predatory activity of the fungi Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34a) on Haemonchus contortus infective larvae (L3) in two experimental assays (A and B). In assay A, two treatments and one control were formed and kept for 7 days in Petri dishes with 2% water-agar. Each treatment consisted of 1000 H. contortus L3 and 1000 conidia of only one fungal isolate, and the control group consisted of 1000 L3, without fungus, with 10 repetitions per group. In assay B, 1000 conidia of one of the fungal isolates, AC001 or NF34a, were added to coprocultures made from 20 g of faeces collected from sheep naturally infected with H. contortus. At the end of the experiment, the Baermann method was used to count the non-predated larvae of all Petri dishes from treatment and control groups. In assay A, no difference was observed (P>0.05) between the groups treated with AC001 and NF34a fungi. A difference was observed (P < 0.05) between the treated and control groups. The L3 reduction percentages at the end of the experiment were 87.75 and 85.57%, respectively, for the fungal isolates compared to the control group. In assay B, the reduction percentages for conidia of these isolates were 85.82 and 87.32%, respectively. The results obtained show that D. flagrans (AC001) and M. thaumasium (NF34a) were effective in the in vitro control of sheep H. contortus L3 and could be used in the biological control of this nematode.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Haemonchus/crescimento & desenvolvimento , Haemonchus/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento , Animais , Antibiose , Fezes/microbiologia , Fezes/parasitologia , Larva/crescimento & desenvolvimento , Larva/microbiologia , Carga Parasitária , Controle Biológico de Vetores , Ovinos , Análise de Sobrevida
12.
J Helminthol ; 85(1): 7-11, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20338078

RESUMO

Three concentrations of chlamydospores of the nematophagous fungus Pochonia chlamydosporia (1000, 10,000 and 20,000 per Petri dish) were evaluated in vitro on Taenia taeniaeformis eggs. Chlamydospores at each concentration were cultured in two different media: 2% water-agar (2%WA) and 2% corn-meal-agar (2%CMA). Taenia taeniaeformis eggs were plated in each chlamydospore concentration in 2%WA and 2%CMA (treated groups) and without fungus (control group). Eggs were removed from each Petri dish at intervals of 7, 14 and 21 days and classified according to ovicidal activity (type 1, type 2 and type 3 effects). Plates containing 2%CMA showed the highest percentages for type 3 effect (81.3%) on the 21st day of observation. A difference (P < 0.01) between the media 2%WA and 2%CMA for type 1 effect was observed only at a concentration of 1000 chlamydospores on the 7th day. There were differences (P < 0.01) between 2%WA and 2%CMA on the 14th and 21st days, at the concentration of 20,000 chlamydospores, for type 1 and type 3 effects. Regression curves for type 3 effect in 2%WA and 2%CMA at the tested concentrations showed higher ovicidal activity with increasing chlamydospore concentrations. Results indicate that, at concentrations of 1000, 10,000 and 20,000 per Petri dish, chlamydospores of P. chlamydosporia effectively destroyed T. taeniaeformis eggs and can be considered a potential biological control agent for this cestode.


Assuntos
Hypocreales/crescimento & desenvolvimento , Óvulo/microbiologia , Controle Biológico de Vetores/métodos , Esporos Fúngicos/crescimento & desenvolvimento , Taenia/microbiologia , Animais , Meios de Cultura , Taenia/crescimento & desenvolvimento
13.
J Helminthol ; 85(2): 164-70, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20682085

RESUMO

Protease production from Duddingtonia flagrans (isolate AC001) was optimized and the larvicidal activity of the enzymatic extract was evaluated on infective horse cyathostomin larvae (L3). Duddingtonia flagrans was grown in liquid medium with eight different variables: glucose, casein, bibasic potassium phosphate (K2HPO4), magnesium sulphate (MgSO4), zinc sulphate (ZnSO4), ferrous sulphate (FeSO4), copper sulphate (CuSO4) and temperature. The Plackett-Burman analysis showed a significant influence of MgSO4, CuSO4 and casein (P < 0.05) on protease production by D. flagrans in liquid medium. Central composite design indicated that the highest proteolytic activity was 39.56 U/ml as a function of the concentrations of casein (18.409 g/l), MgSO4 (0.10 g/l) and CuSO4 (0.50 mg/l). A significant difference (P < 0.01) was found for the larval number between the treated and control groups at the end of the experiment. A reduction of 95.46% in the number of free-living larvae was found in the treated group compared with the control. The results of this study suggest that protease production by D. flagrans (AC001) in liquid medium was optimized by MgSO4, CuSO4 and casein, showing that the optimized enzymatic extract exerted larvicidal activity on cyathostomins and therefore may contribute to large-scale industrial production.


Assuntos
Anti-Helmínticos/metabolismo , Anti-Helmínticos/farmacologia , Duddingtonia/enzimologia , Peptídeo Hidrolases/metabolismo , Peptídeo Hidrolases/farmacologia , Estrongilídios/efeitos dos fármacos , Animais , Anti-Helmínticos/isolamento & purificação , Meios de Cultura/química , Duddingtonia/crescimento & desenvolvimento , Cavalos , Larva/efeitos dos fármacos , Peptídeo Hidrolases/isolamento & purificação , Proteólise , Análise de Sobrevida
14.
Biomed Pharmacother ; 136: 111123, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33486211

RESUMO

Cancer is one of the main causes of death in the world and thus a global public health problem. Among the treatments available for cancer are surgery, radiotherapy, and chemotherapy. Currently, there is increased interest in the combination of two or more antitumor agents to achieve a synergistic effect in cancer therapy. Doxorubicin (DOX), a chemotherapeutic which has a potent antineoplastic action, has been used in the treatment of various tumors. However, the use of DOX is limited, mainly due to the cardiotoxicity. Therefore, nanostructured systems, such as liposomes, have been developed to carry this drug and target the tumor region, since tumor tissues present enhanced permeability and retention for nanosystems. Cardiac glycosides, such as digitoxin, have recently shown great antitumor potential despite the low therapeutic index which may limit their use. Furthermore, some compounds of this class have low water solubility, which makes their in vivo administration difficult. In this context, liposomes represent a valid strategy to carry simultaneously antitumor drugs allowing their intravenous administration. In this study, liposomes loaded with glucoevatromonoside containing peracetylated glucose hydroxyl groups (GEVPG) and DOX at molar ratio of 1:1 (SpHL-GEVPG:DOX 1:1) were developed, and their chemical and physicochemical properties were evaluated. This formulation presented a combination index (CI) lower than 1 at inhibitory concentration of 90 % growth (IC90) for three human breast tumor lines evaluated (0.52 ± 0.39 for MDA-MB-231, 0.19 ± 0.13 for MCF-7, and 0.99 ± 0.09 for SKBR-3). These results indicate a synergistic cytotoxic effect of the GEVPG and DOX combination encapsulated in liposomes. In addition, SpHL-GEVPG:DOX 1:1 presented selectivity towards these cancer cells. Long-term in vitro cytotoxicity studies demonstrated that MDA-MB-231 surviving cells after treatment with SpHL-GEVPG:DOX 1:1 did not recover proliferation capacity after 21 d. From the studies of cell cycle and death pathway evaluation, it was observed that SpHL-GEVPG:DOX 1:1 arrested the cell cycle in the G2/M phase and similarly induced apoptosis and necrosis. However, SpHL-GEVPG:DOX at molar ratio of 1:1 showed lower induction of both apoptotic and necrotic pathways compared to free DOX and SpHL-DOX, suggesting that the mechanism of death involved may not be related to necrosis or apoptosis. Lastly, SpHL-GEVPG:DOX 1:1 showed a good storage stability for 90 d at 4 °C. Therefore, the results of the present work indicate the potential use of SpHL-GEVPG:DOX 1:1 as a new anticancer formulation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cardenolídeos/farmacologia , Doxorrubicina/farmacologia , Lipídeos/química , Protocolos de Quimioterapia Combinada Antineoplásica/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Cardenolídeos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Composição de Medicamentos , Sinergismo Farmacológico , Feminino , Humanos , Lipossomos , Células MCF-7 , Necrose , Fatores de Tempo
15.
Cryobiology ; 60(3): 301-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20152822

RESUMO

Transplantation using hematopoietic stem cells from umbilical cord blood (UCB) is a life-saving treatment option for patients with select oncologic diseases, immunologic diseases, bone marrow failure, and others. Often this transplant modality requires cryopreservation and storage of hematopoietic stem cells (HSC), which need to remain cryopreserved in UCB banks for possible future use. The most widely used cryoprotectant is dimethylsulfoxide (Me(2)SO), but at 37 degrees C, it is toxic to cells and for patients, infusion of cryopreserved HSC with Me(2)SO has been associated with side effects. Freezing of cells leads to chemical change of cellular components, which results in physical disruption. Reactive oxygen species (ROS) generation also has been implicated as cause of damage to cells during freezing. We assessed the ability of two bioantioxidants and two disaccharides, to enhance the cryopreservation of UCB. UCB was processed and subjected to cryopreservation in solutions containing different concentrations of Me(2)SO, bioantioxidants and disaccharides. Samples were thawed, and then analysed by: flow cytometry analysis, CFU assay and MTT viability assay. In this study, our analyses showed that antioxidants, principally catalase, performed greater preservation of: CD34+ cells, CD123+ cells, colony-forming units and cell viability, all post-thawed, compared with the standard solution of cryopreservation. Our present studies show that the addition of catalase improved the cryopreservation outcome. Catalase may act on reducing levels of ROS, further indicating that accumulation of free radicals indeed leads to death in cryopreserved hematopoietic cells.


Assuntos
Antioxidantes/farmacologia , Preservação de Sangue/métodos , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Catalase/farmacologia , Separação Celular , Sobrevivência Celular/efeitos dos fármacos , Dissacarídeos/farmacologia , Sangue Fetal/citologia , Sangue Fetal/efeitos dos fármacos , Citometria de Fluxo , Humanos , Células-Tronco/efeitos dos fármacos , Sacarose/farmacologia , Trealose/farmacologia
16.
Reprod Domest Anim ; 45(5): 907-14, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19453495

RESUMO

The objectives of this investigation were to understand transplacental transport of iron by secreted uteroferrin (UF) and haemophagous areas of water buffalo placenta and clarify the role(s) of blood extravasation at the placental-maternal interface. Placentomes and interplacentomal region of 51 placentae at various stages of gestation were fixed, processed for light and transmission electron microscopy, histochemistry and immunohistochemistry. Haemophagous areas were present in placentomes collected between 4 and 10 months of pregnancy. Perl's reaction for ferric iron was negative in placentomes, but positive in endometrial glands. Positive staining for UF indicated areas in which it was being taken up by phagocytosis and/or fluid phase pinocytosis in areolae of the interplacentomal mesenchyme, with little staining in endometrial stroma. Imunohistochemistry detected UF in trophectoderm of haemophagous regions of placentomes and in other parts of the foetal villous tree, but the strongest immunostaining was in the epithelial cells and lumen of uterine glands. Ultrastructural analyses indicated that erythrophagocytosis was occurring and that erythrocytes were present inside cells of the chorion that also contained endocytic vesicles and caveolae. Results of this study indicate that both the haemophagous areas of placentomes and the areolae at the interface between chorion and endometrial glands are important sites for iron transfer from mother to foetal-placental tissues in buffalo throughout pregnancy.


Assuntos
Fosfatase Ácida/metabolismo , Búfalos/metabolismo , Ferro/metabolismo , Isoenzimas/metabolismo , Troca Materno-Fetal/fisiologia , Fagocitose/fisiologia , Placenta/metabolismo , Animais , Transporte Biológico Ativo , Eritrócitos/metabolismo , Feminino , Gravidez , Fosfatase Ácida Resistente a Tartarato
17.
J Helminthol ; 84(1): 21-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19570314

RESUMO

The action of four fungal isolates of the species Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34a) and Pochonia chlamydosporia (VC1 and VC4) on eggs of Oxyuris equi and Austroxyuris finlaysoni was evaluated in two assays (A and B). Eggs of O. equi (Test A) and A. finlaysoni (Test B) were plated on Petri dishes with 2% water-agar with grown fungal isolates and control without fungus. After 5, 10 and 15 days, 100 eggs were collected and classified according to the following parameters: type 1 effect, physiological and biochemical effect without morphological damage to the eggshell; type 2 effect, lytic effect with morphological alteration of the eggshell and embryo; and type 3 effect, lytic effect with morphological alteration of the eggshell and embryo, hyphal penetration and internal egg colonization. Pochonia chlamydosporia isolates VC1 and VC4 showed ovicidal activity for type 1, 2 and 3 effects on eggs of O. equi and eggs of A. finlaysoni. In vitro assays A and B showed that P. chlamydosporia had a negative influence on eggs of O. equi and A. finlaysoni and can be considered as a potential biological control agent of nematodes.


Assuntos
Hypocreales/fisiologia , Nematoides/microbiologia , Controle Biológico de Vetores/métodos , Animais , Ascomicetos/fisiologia , Feminino , Masculino , Nematoides/fisiologia , Óvulo/microbiologia , Óvulo/fisiologia
18.
Reprod Domest Anim ; 44 Suppl 2: 239-42, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19754577

RESUMO

The aim of this research was to analyze oestrogen receptor-alpha (ERalpha), ERbeta and progesterone receptor (PR) gene expression in the canine oocyte and cumulus cells throughout the oestrous cycle. Ovaries from 38 bitches were recovered after ovariohysterectomy and sliced. The phase of the oestrous cycle was determined by vaginal cytology, vaginoscopy and serum hormonal measurements. Oocytes were mechanically denuded by repeated pipetting. For each phase of the cycle, a sample was composed by a pool of 50 oocytes (sample number: prooestrus = 3, oestrus = 8, dioestrus = 5 and anoestrus = 5) or a pool of cumulus cells (prooestrus = 4, oestrus = 7, dioestrus = 4 and anoestrus = 6). Oocyte and cumulus cells' total RNA was isolated and reverse transcription was conducted to perform real-time PCR. Oestrogen receptor-alpha was expressed throughout the cycle in the oocyte (33.33%, 25.0%, 20.0% and 60.0% for prooestrus, oestrus, dioestrus and anoestrus, respectively) and cumulus cells (50.0%, 47.14%, 25.0% and 66.67% for prooestrus, oestrus, dioestrus and anoestrus, respectively). In the oocyte, the ERbeta was also expressed in all phases of the cycle (33.33%, 50.0%, 20.0% and 60.0% for prooestrus, oestrus, dioestrus and anoestrus, respectively), whereas in cumulus cells, ERbeta was only expressed during prooestrus (50%) and oestrus (14.29%). Interestingly, while the oocyte PR was not detected in any phase of the cycle, this receptor was expressed during prooestrus (50%), oestrus (42.86%) and anoestrus (16.67%) in cumulus cells. In conclusion, canine oocytes express ERalpha and ERbeta throughout the oestrous cycle, however, there is a lack of PR expression in all these phases. Moreover, in cumulus cells, only ERalpha was expressed throughout the oestrous cycle.


Assuntos
Células do Cúmulo/metabolismo , Cães/fisiologia , Ciclo Estral/fisiologia , Oócitos/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Animais , Feminino , Regulação da Expressão Gênica/fisiologia
19.
J Helminthol ; 83(3): 231-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19144215

RESUMO

The predatory capacity of nematophagous fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34a), M. appendiculatum (CGI), M. sinense (SF53), Arthrobotrys conoides (I-40), A. cladodes (CG719) and A. robusta (I-31) on infective Ancylostoma sp. larvae (L3) was evaluated. Compared with the control without fungi there was a significant reduction (P < 0.05) of 87.02%, 82.74%, 47.93%, 60.49%, 76.89%, 71.33% and 86.02% in the mean number of Ancylostoma sp. (L3) recovered from treatments with the isolates AC001, NF34a, CGI, SF53, I-40, CG719 and I-31, respectively. Isolates AC001, I-31 and NF34a were more effective in capturing L3 during the in vitro assay. Isolates were then in vivo evaluated for the capacity to remain viable after passing through the gastrointestinal tract of dogs, while still maintaining their predatory activity against L3. Fungal isolates survived the passage and showed efficient predation 48 h after fungal administration to the dogs (P < 0.05). After this time, only the isolate NF34a remained effective up to 96 h after administration (P < 0.05). Monacrosporium thaumasium, D. flagrans and A. robusta are potential biological control agents of Ancylostoma sp. in dogs.


Assuntos
Ancylostoma/microbiologia , Ancilostomíase/microbiologia , Doenças do Cão/microbiologia , Fungos/fisiologia , Trato Gastrointestinal/microbiologia , Análise de Variância , Animais , Doenças do Cão/parasitologia , Cães , Fungos/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Larva/microbiologia , Distribuição Aleatória , Esporos Fúngicos
20.
J Helminthol ; 83(4): 303-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19216825

RESUMO

Angiostrongylus vasorum is a nematode that parasitizes domestic dogs and wild canids. We compared the predatory capacity of isolates from the predatory fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34), Monacrosporium sinense (SF53) and Arthrobotrys robusta (I31) on first-stage larvae (L1) of A. vasorum under laboratory conditions. L1 A. vasorum were plated on 2% water-agar (WA) Petri dishes marked into 4 mm diameter fields with the four grown isolates and a control without fungus. Plates of treated groups contained each 1000 L1 A. vasorum and 1000 conidia of the fungal isolates AC001, NF34, SF53 and I31 on 2% WA. Plates of the control group (without fungus) contained only 1000 L1 A. vasorum on 2% WA. Ten random fields (4 mm diameter) were examined per plate of treated and control groups, every 24 h for 7 days. Nematophagous fungi were not observed in the control group during the experiment. There was no variation in the predatory capacity among the tested fungal isolates (P>0.05) during the 7 days of the experiment. There was a significant reduction (P < 0.05) of 80.3%, 74.5%, 74.2% and 71.8% in the means of A. vasorum L1 recovered from treatments with isolates AC001, NF34, SF53 and I31, respectively, compared to the control without fungi. In this study, the four isolates of predatory fungi were efficient in the in vitro capture and destruction of A. vasorum L1, confirming previous work on the efficiency of nematophagous fungi in the control of nematode parasites of dogs and as a possible alternative method of biological control.


Assuntos
Angiostrongylus/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Nematoides/crescimento & desenvolvimento , Infecções por Nematoides/prevenção & controle , Angiostrongylus/microbiologia , Animais , Cães , Interações Hospedeiro-Parasita , Larva/microbiologia , Nematoides/microbiologia , Infecções por Nematoides/veterinária , Contagem de Ovos de Parasitas , Controle Biológico de Vetores/métodos , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA