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1.
Mol Neurobiol ; 56(5): 3260-3279, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30117104

RESUMO

Glioblastoma is the worst and most common primary brain tumor. Here, we demonstrated the role of CD73, an enzyme responsible for adenosine (ADO) production, in glioblastoma progression. ADO increased glioma cell viability via A1 receptor sensitization. CD73 downregulation decreased glioma cell migration and invasion by reducing metalloproteinase-2 and vimentin expression and reduced cell proliferation by 40%, which was related to necrosis and sub-G1 phase blockage of cell cycle. Those effects also involved the stimulation of Akt/NF-kB pathways. Additionally, CD73 knockdown or enzyme inhibition potentiated temozolomide cytotoxic effect on glioma cells by decreasing the IC50 value and sensitizing cells to a non-cytotoxic drug concentration. CD73 inhibition also decreased in vivo rat glioblastoma progression. Delivery of siRNA-CD73 or APCP reduced tumor size by 45 and 40%, respectively, when compared with control. This effect was followed by a parallel 95% reduction of ADO levels in cerebrospinal fluid, indicating the role of extracellular ADO in in vivo glioma growth. Treatment did not induce systemic damage or mortality. Altogether, we conclude that CD73 is an interesting target for glioblastoma treatment and its inhibition may provide new opportunities to improve the treatment of brain tumors. Graphical Abstract ᅟ.


Assuntos
5'-Nucleotidase/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Regulação para Baixo/genética , Glioblastoma/genética , Glioblastoma/patologia , 5'-Nucleotidase/antagonistas & inibidores , 5'-Nucleotidase/metabolismo , Adenosina/metabolismo , Animais , Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular , Progressão da Doença , Técnicas de Silenciamento de Genes , Glioblastoma/sangue , Glioblastoma/tratamento farmacológico , Humanos , Metaloproteinase 2 da Matriz/metabolismo , NF-kappa B/metabolismo , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Receptores Purinérgicos P1/metabolismo , Transdução de Sinais , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Vimentina/metabolismo
2.
Braz J Microbiol ; 44(2): 485-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24294244

RESUMO

The identification of pathogens of viral (Rotavirus, Coronavirus), parasitic (Toxocara spp.) and bacterial (Escherichia coli, Salmonella spp., Rhodococcus equi) origin shed in feces, and the virulence profile of R. equi and E. coli isolates were investigated in 200 samples of sand obtained from 40 parks, located in central region of state of Sao Paulo, Brazil, using different diagnostic methods. From 200 samples analyzed, 23 (11.5%) strains of R. equi were isolated. None of the R. equi isolates showed a virulent (vapA gene) or intermediately virulent (vapB gene) profiles. Sixty-three (31.5%) strains of E. coli were identified. The following genes encoding virulence factors were identified in E. coli: eae, bfp, saa, iucD, papGI, sfa and hly. Phylogenetic classification showed that 63 E. coli isolates belonged to groups B1 (52.4%), A (25.4%) and B2 (22.2%). No E. coli serotype O157:H7 was identified. Eggs of Toxocara sp. were found in three parks and genetic material of bovine Coronavirus was identified in one sample of one park. No Salmonella spp. and Rotavirus isolates were identified in the samples of sand. The presence of R. equi, Toxocara sp, bovine Coronavirus and virulent E. coli isolates in the environment of parks indicates that the sanitary conditions of the sand should be improved in order to reduce the risks of fecal transmission of pathogens of zoonotic potential to humans in these places.


Assuntos
Coronavirus Bovino/isolamento & purificação , Escherichia coli/isolamento & purificação , Rhodococcus equi/isolamento & purificação , Microbiologia do Solo , Toxocara/isolamento & purificação , Animais , Brasil , Escherichia coli/classificação , Escherichia coli/genética , Humanos , Rhodococcus equi/genética , Fatores de Virulência/genética
3.
Braz. j. microbiol ; 44(2): 485-492, 2013. tab
Artigo em Inglês | LILACS | ID: lil-688570

RESUMO

The identification of pathogens of viral (Rotavirus, Coronavirus), parasitic (Toxocara spp.) and bacterial (Escherichia coli, Salmonella spp., Rhodococcus equi) origin shed in feces, and the virulence profile of R. equi and E. coli isolates were investigated in 200 samples of sand obtained from 40 parks, located in central region of state of Sao Paulo, Brazil, using different diagnostic methods. From 200 samples analyzed, 23 (11.5%) strains of R. equi were isolated. None of the R. equi isolates showed a virulent (vapA gene) or intermediately virulent (vapB gene) profiles. Sixty-three (31.5%) strains of E. coli were identified. The following genes encoding virulence factors were identified in E. coli: eae, bfp, saa, iucD, papGI, sfa and hly. Phylogenetic classification showed that 63 E. coli isolates belonged to groups B1 (52.4%), A (25.4%) and B2 (22.2%). No E. coli serotype O157:H7 was identified. Eggs of Toxocara sp. were found in three parks and genetic material of bovine Coronavirus was identified in one sample of one park. No Salmonella spp. and Rotavirus isolates were identified in the samples of sand. The presence of R. equi, Toxocara sp, bovine Coronavirus and virulent E. coli isolates in the environment of parks indicates that the sanitary conditions of the sand should be improved in order to reduce the risks of fecal transmission of pathogens of zoonotic potential to humans in these places.


Assuntos
Animais , Humanos , Coronavirus Bovino/isolamento & purificação , Escherichia coli/isolamento & purificação , Rhodococcus equi/isolamento & purificação , Microbiologia do Solo , Toxocara/isolamento & purificação , Brasil , Escherichia coli/classificação , Escherichia coli/genética , Rhodococcus equi/genética , Fatores de Virulência/genética
4.
Braz. J. Microbiol. ; 44(2): 485-492, 2013.
Artigo em Inglês | VETINDEX | ID: vti-717

RESUMO

The identification of pathogens of viral (Rotavirus, Coronavirus), parasitic (Toxocara spp.) and bacterial (Escherichia coli, Salmonella spp., Rhodococcus equi) origin shed in feces, and the virulence profile of R. equi and E. coli isolates were investigated in 200 samples of sand obtained from 40 parks, located in central region of state of Sao Paulo, Brazil, using different diagnostic methods. From 200 samples analyzed, 23 (11.5%) strains of R. equi were isolated. None of the R. equi isolates showed a virulent (vapA gene) or intermediately virulent (vapB gene) profiles. Sixty-three (31.5%) strains of E. coli were identified. The following genes encoding virulence factors were identified in E. coli: eae, bfp, saa, iucD, papGI, sfa and hly. Phylogenetic classification showed that 63 E. coli isolates belonged to groups B1 (52.4%), A (25.4%) and B2 (22.2%). No E. coli serotype O157:H7 was identified. Eggs of Toxocara sp. were found in three parks and genetic material of bovine Coronavirus was identified in one sample of one park. No Salmonella spp. and Rotavirus isolates were identified in the samples of sand. The presence of R. equi, Toxocara sp, bovine Coronavirus and virulent E. coli isolates in the environment of parks indicates that the sanitary conditions of the sand should be improved in order to reduce the risks of fecal transmission of pathogens of zoonotic potential to humans in these places.(AU)


Assuntos
Rhodococcus , Humanos , Toxocara , Escherichia coli , Fatores de Virulência
5.
Parasitology ; 139(1): 26-36, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21939585

RESUMO

Chagas' disease, caused by the protozoan Trypanosoma cruzi, represents a serious health problem in Latin America, and the available chemotherapy, which is based on 2 nitro-derivatives, is not satisfactory. In folk medicine, natural products including naphthoquinones have been employed for the treatment of different parasitic diseases. In the pursuit of alternative drugs for Chagas' disease, we investigated the mechanism of action of the triazolic naphthoquinone (TN; 2,2-dimethyl-3-(4-phenyl-1H-1,2,3-triazol-1-yl)-2,3-dihydronaphtho[1,2-b]furan-4,5-dione), which is the most active compound against T. cruzi trypomastigotes among a series of naphthofuranquinones. TN was active against the 3 parasite forms producing a dose-dependent inhibitory effect. In epimastigotes, TN induced reservosome disruption, flagellar blebbing, Golgi disorganization, the presence of cytosolic concentric membrane structures and abnormal multiflagellar parasites. The treatment also led to the appearance of well-developed endoplasmic reticulum profiles surrounding organelles that associated with an increase in monodansylcadaverine labelling, suggesting autophagy as part of the TN mechanism of action. Interestingly, no ultrastructural damage was detected in the mitochondria of naphthoquinone-treated epimastigotes. Flow cytometric analysis demonstrated an impairment of mitosis, an increase in ROS production and the maintenance of mitochondrial membrane potential. TN could be a good starting point in the investigation of a chemotherapeutic approach for the treatment of Chagas' disease.


Assuntos
Naftoquinonas/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Autofagia/efeitos dos fármacos , Citometria de Fluxo , Concentração Inibidora 50 , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mitose/efeitos dos fármacos , Organelas/efeitos dos fármacos
6.
Arq. bras. med. vet. zootec ; 62(4): 985-988, ago. 2010. tab
Artigo em Português | VETINDEX | ID: vti-5905

RESUMO

The uncommon occurrence of bovine mastitis by Pasteurella multocida is reported in nine cows. Mammary pasteurellosis was predominantly diagnosed predominantly in clinical cases, in dairy cows milked in the presence of calves. Low interference of immunosuppressive or predispose factors and absence of pulmonary signs were observed in animals. In vitro multiple drug resistance of isolates was observed to three or more conventional antimicrobials, especially with use of tetracycline and gentamicin. Epidemiologic findings, clinical signs, and antimicrobial profile were discussed in nine cases of bovine mastitis caused by P. multocida.(AU)


Assuntos
Animais , Feminino , Bovinos , Mastite Bovina/microbiologia , Infecções por Pasteurella/veterinária , Resistência Microbiana a Medicamentos , Testes de Sensibilidade Microbiana , Bovinos
7.
Arq. bras. med. vet. zootec ; 62(4): 985-988, Aug. 2010. tab
Artigo em Português | LILACS | ID: lil-562069

RESUMO

The uncommon occurrence of bovine mastitis by Pasteurella multocida is reported in nine cows. Mammary pasteurellosis was predominantly diagnosed predominantly in clinical cases, in dairy cows milked in the presence of calves. Low interference of immunosuppressive or predispose factors and absence of pulmonary signs were observed in animals. In vitro multiple drug resistance of isolates was observed to three or more conventional antimicrobials, especially with use of tetracycline and gentamicin. Epidemiologic findings, clinical signs, and antimicrobial profile were discussed in nine cases of bovine mastitis caused by P. multocida.


Assuntos
Animais , Feminino , Bovinos , Resistência Microbiana a Medicamentos , Infecções por Pasteurella/veterinária , Mastite Bovina/microbiologia , Bovinos , Testes de Sensibilidade Microbiana
8.
Arq. bras. med. vet. zootec ; 61(3): 745-748, jun. 2009. tab
Artigo em Português | VETINDEX | ID: vti-6321

RESUMO

Uncommon outbreak of mastitis caused by Pseudomonas aeruginosa strains in 19 cows was reported.Enrofloxacin (73.7%) and danofloxacin were in vitro effective against those strains. In vitro multipledrug resistance of the isolated bacteria was observed to five or more conventional antimicrobials usedfor mammary therapy, including ampicillin (100.0%), cefalexin (100.0%), cloxacillin (100.0%),gentamicin (100.0%), penicillin/novobiocin (100.0%), cefoperazone (52.6%), tetracycline (100.0%),florfenicol (94.7%), and neomycin (73.7%). Epidemiological findings, clinical signs, in vitrosusceptibility profile, control measures, and public health risks were discussed in cows infected by P. aeruginosa.(AU)


Assuntos
Animais , Feminino , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/isolamento & purificação , Mastite Bovina/epidemiologia , Resistência Microbiana a Medicamentos , Bovinos , Brasil/epidemiologia
9.
Arq. bras. med. vet. zootec ; 61(3): 745-748, jun. 2009. tab
Artigo em Português | LILACS | ID: lil-519470

RESUMO

Uncommon outbreak of mastitis caused by Pseudomonas aeruginosa strains in 19 cows was reported.Enrofloxacin (73.7%) and danofloxacin were in vitro effective against those strains. In vitro multipledrug resistance of the isolated bacteria was observed to five or more conventional antimicrobials usedfor mammary therapy, including ampicillin (100.0%), cefalexin (100.0%), cloxacillin (100.0%),gentamicin (100.0%), penicillin/novobiocin (100.0%), cefoperazone (52.6%), tetracycline (100.0%),florfenicol (94.7%), and neomycin (73.7%). Epidemiological findings, clinical signs, in vitrosusceptibility profile, control measures, and public health risks were discussed in cows infected by P. aeruginosa.


Assuntos
Animais , Feminino , Resistência Microbiana a Medicamentos , Mastite Bovina/epidemiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/isolamento & purificação , Brasil/epidemiologia , Bovinos
10.
Parasitology ; 136(5): 499-510, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19281638

RESUMO

SUMMARY: In a screening of 65 derivatives of natural quinones using bloodstream trypomastigotes of Trypanosoma cruzi, the 3 naphthoimidazoles derived from beta-lapachone - N1, N2 and N3--were selected as the most active. Investigation of their mode of action led to the characterization of mitochondrion, reservosomes and DNA as their main targets, and stimulated further studies on death pathways. Ultrastructural analysis revealed both autophagic (autophagosomes) and apoptotic-like (membrane blebbing) phenotypes. Flow cytometry analysis showed, in N2-treated trypomastigotes, a small increase of phosphatidylserine exposure, and a large increase in the percentage of necrosis, caused by N1 or N2. These death phenotypes were not detected in treated epimastigotes. The strong increase in labelling of monodansyl cadaverine, the inhibition of the death process by wortmannin or 3-methyladenine, the overexpression of ATG genes in treated epimastigotes, together with ultrastructural evidence point to autophagy as the predominant phenotype induced by the naphthoimidazoles. However, there are other pathways occurring concomitantly with variable intensities, justifying the need to detail the molecular features involved.


Assuntos
Autofagia/efeitos dos fármacos , Imidazóis/farmacologia , Naftoquinonas/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Citometria de Fluxo , Imidazóis/síntese química , Imidazóis/química , Microscopia Eletrônica , Naftoquinonas/síntese química , Naftoquinonas/química , Testes de Sensibilidade Parasitária , Fenótipo , Tripanossomicidas/síntese química , Tripanossomicidas/química , Trypanosoma cruzi/genética , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/ultraestrutura
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