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1.
Microb Pathog ; 192: 106706, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763316

RESUMO

Mannheimiahaemolytica is an opportunistic agent of the respiratory tract of bovines, a member of the Pasteurellaceae family, and the causal agent of fibrinous pleuropneumonia. This bacterium possesses different virulence factors, allowing it to colonize and infect its host. The present work describes the isolation and characterization of a serine protease secreted by M. haemolytica serotype 1. This protease was isolated from M. haemolytica cultured media by precipitation with 50 % methanol and ion exchange chromatography on DEAE-cellulose. It is a 70-kDa protease able to degrade sheep and bovine fibrinogen or porcine gelatin but not bovine IgG, hemoglobin, or casein. Mass spectrometric analysis indicates its identity with protease IV of M. haemolytica. The proteolytic activity was active between pH 5 and 9, with an optimal pH of 8. It was stable at 50 °C for 10 min but inactivated at 60 °C. The sera of bovines with chronic or acute pneumonia recognized this protease. Still, it showed no cross-reactivity with rabbit hyperimmune serum against the secreted metalloprotease from Actinobacilluspleuropneumoniae, another member of the Pasteurellaceae family. M. haemolytica secreted proteases could contribute to the pathogenesis of this bacterium through fibrinogen degradation, a characteristic of this fibrinous pleuropneumonia.


Assuntos
Fibrinogênio , Mannheimia haemolytica , Serina Proteases , Animais , Mannheimia haemolytica/enzimologia , Ovinos , Bovinos , Fibrinogênio/metabolismo , Concentração de Íons de Hidrogênio , Serina Proteases/metabolismo , Serina Proteases/isolamento & purificação , Temperatura , Proteólise , Peso Molecular , Gelatina/metabolismo , Estabilidade Enzimática , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/isolamento & purificação , Espectrometria de Massas , Cromatografia por Troca Iônica , Suínos , Fatores de Virulência/metabolismo , Fatores de Virulência/isolamento & purificação
2.
J Fungi (Basel) ; 9(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37755003

RESUMO

We analyzed the global expression patterns of telomerase-negative mutants from haploid cells of Ustilago maydis to identify the gene network required for cell survival in the absence of telomerase. Mutations in either of the telomerase core subunits (trt1 and ter1) of the dimorphic fungus U. maydis cause deficiencies in teliospore formation. We report the global transcriptome analysis of two ter1Δ survivor strains of U. maydis, revealing the deregulation of telomerase-deleted responses (TDR) genes, such as DNA-damage response, stress response, cell cycle, subtelomeric, and proximal telomere genes. Other differentially expressed genes (DEGs) found in the ter1Δ survivor strains were related to pathogenic lifestyle factors, plant-pathogen crosstalk, iron uptake, meiosis, and melanin synthesis. The two ter1Δ survivors were phenotypically comparable, yet DEGs were identified when comparing these strains. Our findings suggest that teliospore formation in U. maydis is controlled by key pathogenic lifestyle and meiosis genes.

3.
FEMS Microbiol Lett ; 3702023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37279906

RESUMO

Actinobacillus seminis is the causal agent of epididymitis and has other effects on the reproductive tracts of small ruminants and bovines. This bacterium causes infection when luteinizing (LH) or follicle-stimulating hormones increase, and hosts reach sexual maturity. LH induces female ovulation and male testosterone production, suggesting that these hormones affect A. seminis pathogenicity. In the present study, we evaluated the effect of testosterone (1-5 ng/ml) or estradiol (5-25 pg/ml) added to culture medium on the in vitro growth, biofilm production, and adhesin expression of A. seminis. Estradiol does not promote the growth of this bacterium, whereas testosterone increased A. seminis planktonic growth 2-fold. Both hormones induced the expression of the elongation factor thermo unstable (EF-Tu) and phosphoglycerate mutase (PGM), proteins that A. seminis uses as adhesins. Estradiol (5 or 10 pg/ml) decreased biofilm formation by 32%, whereas testosterone, even at 5 ng/ml, showed no effect. Both hormones modified the concentrations of carbohydrates and eDNA in biofilms by 50%. Amyloid proteins are characterized by their capacity to bind Congo red (CR) dye. Actinobacillus seminis binds CR dye, and this binding increases in the presence of 5-20 pg/ml estradiol or 4 ng/ml testosterone. The A. seminis EF-Tu protein was identified as amyloid-like protein (ALP). The effect of sexual hormones on the growth and expression of virulence factors of A. seminis seems to be relevant for its colonization and permanence in the host.


Assuntos
Infecções por Actinobacillus , Actinobacillus seminis , Feminino , Masculino , Animais , Bovinos , Actinobacillus seminis/genética , Estradiol/farmacologia , Infecções por Actinobacillus/microbiologia , Testosterona/farmacologia , Fator Tu de Elongação de Peptídeos , Adesinas Bacterianas/genética , Biofilmes
4.
PLoS One ; 18(3): e0281251, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36952474

RESUMO

The RNA subunit of telomerase is an essential component whose primary sequence and length are poorly conserved among eukaryotic organisms. The phytopathogen Ustilago maydis is a dimorphic fungus of the order Ustilaginales. We analyzed several species of Ustilaginales to computationally identify the TElomere RNA (TER) gene ter1. To confirm the identity of the TER gene, we disrupted the gene and characterized telomerase-negative mutants. Similar to catalytic TERT mutants, ter1Δ mutants exhibit phenotypes of growth delay, telomere shortening and low replicative potential. ter1-disrupted mutants were unable to infect maize seedlings in heterozygous crosses and showed defects such as cell cycle arrest and segregation failure. We concluded that ter1, which encodes the TER subunit of the telomerase of U. maydis, have similar and perhaps more extensive functions than trt1.


Assuntos
Telomerase , Ustilaginales , Ustilago , Animais , Telomerase/genética , Telomerase/metabolismo , Ustilaginales/genética , RNA/metabolismo , Estágios do Ciclo de Vida , Ustilago/genética , Ustilago/metabolismo
5.
Front Microbiol ; 14: 1084766, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778889

RESUMO

Introduction: Gallibacterium anatis causes gallibacteriosis in birds. These bacteria produce biofilms and secrete several fimbrial appendages as tools to cause disease in animals. G. anatis strains contain up to three types of fimbriae. Complete genome sequencing is the strategy currently used to determine variations in the gene content of G. anatis, although today only the completely circularized genome of G. anatis UMN179 is available. Methods: The appearance of growth of various strains of G. anatis in liquid culture medium was studied. Biofilm production and how the amount of biofilm was affected by DNase, Proteinase K, and Pronase E enzymes were analyzed. Fimbrial gene expression was performed by protein analysis and qRT-PCR. In an avian model, the pathogenesis generated by the strains G. anatis ESV200 and 12656-12 was investigated. Using bioinformatic tools, the complete genome of G. anatis ESV200 was comparatively studied to search for virulence factors that would help explain the pathogenic behavior of this strain. Results and Discussion: G. anatis ESV200 strain differs from the 12656-12 strain because it produces a biofilm at 20%. G. anatis ESV200 strain express fimbrial genes and produces biofilm but with a different structure than that observed for strain 12656-12. ESV200 and 12656-12 strains are pathogenic for chickens, although the latter is the most virulent. Here, we show that the complete genome of the ESV200 strain is similar to that of the UNM179 strain. However, these strains have evolved with many structural rearrangements; the most striking chromosomal arrangement is a Maverick-like element present in the ESV200 strain.

6.
Front Microbiol ; 13: 951173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051765

RESUMO

Pasteurellaceae family members obtain iron directly from host proteins or through siderophore-dependent mechanisms. Although Gallibacterum anatis expresses different virulence factors, its response to growth under iron restriction is unknown. G. anatis cultured in the presence of 2,2'-dipyridyl, up-expressed an approximately 65 kDa protein and repressed the expression of a 70 kDa protein. MALDI-TOF analysis of those proteins indicated homology with CirA (65 kDa), a protein involved in iron-siderophore acquisition in Mannheimia succinoproducens and a TonB-dependent receptor (70 kDa protein), a protein that binds chicken hemoglobin; however, G. anatis siderophore production was not detected by chromo azurol S (CAS)-BHI agar determination. This putative G. anatis siderophore receptor is under Fur control, but not the hemoglobin binding protein, as observed in G. anatis 12656-12 fur mutant (Ω fur 126.13) grown in the presence or not of 2,2'-dipyridyl. The addition of FeCl3 to the culture medium diminished the growth and biofilm production in approximately 30% and 35%, respectively, in the wild-type strain, but the growth of Ω fur 126.13 strain was not affected and biofilm production increased in 35%. G. anatis Ω fur 126.13 presented lower virulence when it was inoculated to 35-day-old chickens in comparison to the wild-type strain. The induction of more than one iron uptake mechanism could benefit pathogenic microorganisms such as Gallibacterium.

7.
Eur J Med Chem ; 227: 113915, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34695777

RESUMO

Fifteen pyridazino-pyrrolo-quinoxalinium salts were synthesized and tested for their antiprotozoal activity against Leishmania infantum amastigotes. Eleven of them turned out to be leishmanicidal, with EC50 values in the nanomolar range, and displayed low toxicity against the human THP-1 cell line. Selectivity indices for these compounds range from 10 to more than 1000. Compounds 3b and 3f behave as potent inhibitors of the oxidoreductase activity of the essential enzyme trypanothione disulfide reductase (TryR). Interestingly, binding of 3f is not affected by high trypanothione concentrations, as revealed by the noncompetitive pattern of inhibition observed when tested in the presence of increasing concentrations of this substrate. Furthermore, when analyzed at varying NADPH concentrations, the characteristic pattern of hyperbolic uncompetitive inhibition supports the view that binding of NADPH to TryR is a prerequisite for inhibitor-protein association. Similar to other TryR uncompetitive inhibitors for NADPH, 3f is responsible for TryR-dependent reduction of cytochrome c in a reaction that is typically inhibited by superoxide dismutase.


Assuntos
Antiprotozoários/farmacologia , Inibidores Enzimáticos/farmacologia , Leishmania infantum/efeitos dos fármacos , NADH NADPH Oxirredutases/antagonistas & inibidores , Antiprotozoários/síntese química , Antiprotozoários/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Leishmania infantum/metabolismo , Estrutura Molecular , NADH NADPH Oxirredutases/metabolismo , Testes de Sensibilidade Parasitária , Piridazinas/química , Piridazinas/farmacologia , Pirróis/química , Pirróis/farmacologia , Quinoxalinas/química , Quinoxalinas/farmacologia , Sais/síntese química , Sais/química , Sais/farmacologia , Relação Estrutura-Atividade , Células THP-1
8.
Bioorg Med Chem ; 44: 116295, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34246920

RESUMO

Protein tyrosine phosphatase (PTP1B) is an interesting therapeutical target for diabetes, obesity, heart disease and cancer. As such, inhibition of PTP1B using orally administered drugs is still being pursued by academia and pharmaceutical companies. The failure of catalytic-site inhibitors led to the focus in this field being switched to allosteric inhibitors. To date, the non-competitive inhibitors that have reached clinical trials target the site formed by the α3/α6/α7 tunnel or the site found in a disordered C-terminal non-catalytic segment. Herein, pyrrolo[1,2-a]quinoxal-5-inium salts and 4,5-dihydropyrrolo[1,2-a]quinoxalines are synthesized from pyrrolo[1,2-a]quinoxalines by alkylation and reduction, respectively. These compounds showed no toxicity in HepG2 cells and exhibited inhibitory activity against PTP1B, with inhibition percentages of between 37% and 53% at 1 µM and activities (IC50) of between 0.25 and 1.90 µM. The inhibitory activity against T-cell protein tyrosine phosphatase (TC-TPT) was also assayed, with 4,5-dihydropyrrolo[1,2-a]quinoxalines being found to be slightly more active and selective. Compounds from the two series behave as insulin mimetics since they exhibit enhancement of glucose uptake in C2C12 cells. Computational docking studies provide information about the putative binding mode for both series and the preference for the α3/α6/α7 allosteric tunnel.


Assuntos
Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Pirróis/farmacologia , Quinoxalinas/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Pirróis/síntese química , Pirróis/química , Quinoxalinas/síntese química , Quinoxalinas/química , Sais/síntese química , Sais/química , Sais/farmacologia , Relação Estrutura-Atividade
9.
ChemMedChem ; 15(19): 1788-1801, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32909701

RESUMO

PTP1B dephosphorylates insulin receptor and substrates to modulate glucose metabolism. This enzyme is a validated therapeutic target for type 2 diabetes, but no current drug candidates have completed clinical trials. Pyrrolo[1,2-a]quinoxalines substituted at positions C1-C4 and/or C7-C8 were found to be nontoxic to cells and good inhibitors in the low- to sub-micromolar range, with the 4-benzyl derivative being the most potent inhibitor (0.24 µm). Some analogues bearing chlorine atoms at C7 and/or C8 kept potency and showed good selectivity compared to TCPTP (selectivity index >40). The most potent inhibitors behaved as insulin mimetics by increasing glucose uptake. The 4-benzyl derivative inhibited insulin receptor substrate 1 and AKT phosphorylation. Molecular docking and molecular dynamics simulations supported a putative binding mode for these compounds to the allosteric α3/α6/α7 pocket, but inconsistent results in enzyme inhibition kinetics were obtained due to the high tendency of these inhibitors to form stable aggregates. Computational calculations supported the druggability of inhibitors.


Assuntos
Inibidores Enzimáticos/farmacologia , Insulina/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Pirróis/farmacologia , Quinoxalinas/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Glucose/metabolismo , Células Hep G2 , Humanos , Camundongos , Modelos Moleculares , Estrutura Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Pirróis/síntese química , Pirróis/química , Quinoxalinas/síntese química , Quinoxalinas/química , Relação Estrutura-Atividade
10.
Plasmid ; 103: 45-52, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31022414

RESUMO

BACKGROUND: The pOV plasmid isolated from the Pasteurella multocida strain PMOV is a new plasmid, and its molecular characterization is important for determining its gene content and its replicative properties in Pasteurellaceae family bacteria. METHODS: Antimicrobial resistance mediated by the pOV plasmid was tested in bacteria. Purified pOV plasmid DNA was used to transform E. coli DH5α and Gallibacterium anatis 12656-12, including the pBluescript II KS(-) plasmid DNA as a control for genetic transformation. The pOV plasmid was digested with EcoRI for cloning fragments into the pBluescript II KS(-) vector to obtain constructs and to determine the full DNA sequence of pOV. RESULTS: The pOV plasmid is 13.5 kb in size; confers sulfonamide, streptomycin and ampicillin resistance to P. multocida PMOV; and can transform E. coli DH5α and G. anatis 12656-12. The pOV plasmid was digested for the preparation of chimeric constructs and used to transform E. coli DH5α, conferring resistance to streptomycin (plasmid pSEP3), ampicillin (pSEP4) and sulfonamide (pSEP5) on the bacteria; however, similar to pBluescript II KS(-), the chimeric plasmids did not transform G. anatis 12656-12. A 1.4 kb fragment of the streptomycin cassette from pSEP3 was amplified by PCR and used to construct pSEP7, which in turn was used to interrupt a chromosomal DNA locus of G. anatis by double homologous recombination, introducing strA-strB into the G. anatis chromosome. CONCLUSION: The pOV plasmid is a wide-range, low-copy-number plasmid that is able to replicate in some gamma-proteobacteria. Part of this plasmid was integrated into the G. anatis 12656-12 chromosome. This construct may prove to be a useful tool for genetic studies of G. anatis.


Assuntos
Cromossomos Bacterianos/metabolismo , Farmacorresistência Bacteriana/genética , Pasteurella multocida/genética , Pasteurellaceae/genética , Plasmídeos/metabolismo , Ampicilina/farmacologia , Antibacterianos/farmacologia , Pareamento de Bases , Sequência de Bases , Cromossomos Bacterianos/química , Desoxirribonuclease EcoRI/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Recombinação Homóloga , Pasteurella multocida/efeitos dos fármacos , Pasteurella multocida/metabolismo , Pasteurellaceae/efeitos dos fármacos , Pasteurellaceae/metabolismo , Plasmídeos/química , Estreptomicina/farmacologia , Sulfonamidas/farmacologia , Transformação Bacteriana
11.
Genome Announc ; 6(2)2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29326222

RESUMO

The draft genome sequence of Actinobacillus seminis strain ATCC 15768 is reported here. The genome comprises 22 contigs corresponding to 2.36 Mb with 40.7% G+C content and contains several genes related to virulence, including a putative RTX protein.

12.
J Microbiol ; 55(9): 745-752, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28865072

RESUMO

Gallibacterium, which is a bacterial pathogen in chickens, can form biofilms. Amyloid proteins present in biofilms bind Congo red dye. The aim of this study was to characterize the cell-surface amyloid-like protein expressed in biofilms formed by Gallibacterium strains and determine the relationship between this protein and curli, which is an amyloid protein that is commonly expressed by members of the Enterobacteriaceae family. The presence of amyloid-like proteins in outer membrane protein samples from three strains of G. anatis and one strain of Gallibacterium genomospecies 2 was evaluated. A protein identified as elongation factor-Tu (EF-Tu) by mass spectrometric analysis and in silico analysis was obtained from the G. anatis strain F149T. This protein bound Congo red dye, cross-reacted with anti-curli polyclonal serum, exhibited polymerizing properties and was present in biofilms. This protein also reacted with pooled serum from chickens that were experimentally infected with G. anatis, indicating the in vivo immunogenicity of this protein. The recombinant EF-Tu purified protein, which was prepared from G. anatis 12656-12, polymerizes under in vitro conditions, forms filaments and interacts with fibronectin and fibrinogen, all of which suggest that this protein functions as an adhesin. In summary, EF-Tu from G. anatis presents amyloid characteristics, is present in biofilms and could be relevant for the pathogenesis of G. anatis.


Assuntos
Proteínas Amiloidogênicas/metabolismo , Aderência Bacteriana , Biofilmes , Pasteurellaceae/metabolismo , Fator Tu de Elongação de Peptídeos/metabolismo , Proteínas Amiloidogênicas/química , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Galinhas/microbiologia , Simulação por Computador , Vermelho Congo/metabolismo , Infecções por Pasteurellaceae/microbiologia , Infecções por Pasteurellaceae/veterinária , Fator Tu de Elongação de Peptídeos/análise , Fator Tu de Elongação de Peptídeos/química , Fator Tu de Elongação de Peptídeos/imunologia , Doenças das Aves Domésticas/microbiologia , Ligação Proteica , Domínios Proteicos , Fatores de Virulência
13.
Jundishapur J Microbiol ; 8(9): e27953, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26495114

RESUMO

BACKGROUND: Bacillus thuringiensis is the most successful biological control agent, however, studies so far have shown that B. thuringiensis is very sensitive to environmental factors such as soil moisture and pH. Ultraviolet light from the sun had been considered as the main limiting factor for its persistence in soil and it has recently been shown that the antagonism exerted by other native soil organisms, such as Pseudomonas fluorescens, is a determining factor in the persistence of this bacterium under in vitro culture conditions. OBJECTIVES: The aim of the present investigation was to analyze the population dynamics of B. thuringiensis and its interaction with P. fluorescens using microbiological and molecular methods in soil, under different conditions, and to determinate the effect of nutrients and moisture on its interaction. MATERIALS AND METHODS: The monitoring was performed by microbiological methods, such as viable count of bacteria, and molecular methods such as Polymerase Chain Reaction (PCR) and hybridization, using the direct extraction of DNA from populations of inoculated soil. RESULTS: The analysis of the interaction between B. thuringiensis and P. fluorescens in soil indicated that the disappearance of B. thuringiensis IPS82 is not dependent on the moisture but the composition of nutrients that may be affecting the secretion of toxic compounds in the environment of P. fluorescens. The results showed that the recovered cells were mostly spores and not vegetative cells in all proved treatments. The molecular methods were effective for monitoring bacterial population inoculated in soil. CONCLUSIONS: Bacillus thuringiensis is very sensitive to the interaction of P. fluorescens, however is capable to survive in soil due to its capacity of sporulate. Some of the cells in the form of spores germinated and folded slightly and remained in a constant cycle of sporulation and germination. This confirms that B. thuringiensis IPS82 can germinate, grow and sporulate in soil.

14.
Rev Med Inst Mex Seguro Soc ; 53 Suppl 2: S172-7, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26462513

RESUMO

Human papillomavirus (HPV) genome codifies proteins with oncogenic activity, such as E7. Due to its structural characteristics, the E7 protein may interact with a great variety of cellular proteins. Some of these proteins act as cell-cycle regulators and other proteins function as transcription factors. These interactions play an important role in the induction of mitogenic pathways, in G1/S progression, and the inhibition of cellular differentiation, which increases chromosomal instability. The aim of this study is to describe the interactions of HPV E7 protein with different cellular proteins, and their contribution in the development of cervical cancer.


El genoma del virus de papiloma humano (VPH) codifica proteínas con actividad oncogénica, entre las que se encuentra la E7. Las características estructurales de la proteína E7 le confieren la capacidad de interactuar con una amplia gama de proteínas celulares, algunas de las cuales actúan como reguladores del ciclo celular y otras como factores de transcripción. A través de estas interacciones, la proteína E7 induce la progresión del ciclo celular de la fase de reposo (G1) a la de síntesis (S), la iniciación de la mitosis y la inhibición de la diferenciación celular; además, esta proteína genera inestabilidad cromosómica. La presente revisión tiene como finalidad describir las interacciones de la proteína E7 del VPH con diferentes proteínas celulares, así como su contribución al desarrollo del cáncer cervical.


Assuntos
Transformação Celular Neoplásica/metabolismo , Papillomaviridae/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Neoplasias do Colo do Útero/virologia , Biomarcadores/metabolismo , Feminino , Humanos , Neoplasias do Colo do Útero/metabolismo
15.
Eur J Med Chem ; 93: 83-92, 2015 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-25659754

RESUMO

Condensed polycyclic heteroaromatic cations bearing a bridgehead nitrogen with pyridazino[1',6':1,2]pyrido[3,4-b]indolinium and pyridazino[1,6-a]benzimidazolium structures were assayed as inhibitors of LPS-induced TNF-α production by THP-1 cells. The hit compound 1e, which had the best IC50 value (4.49 µM) and low toxicity, was further assayed on human PMBCs (IC50 3.91 µM) and monocytes (IC50 1.82 µM). This compound also inhibited TNF-α production following poly I:C stimulation of human monocytes and monocyte-derived dendritic cells; in the latter case, inhibition of IL-12 production was also observed. Compound 1e was also able to inhibit TNF-α expression at the transcriptional level and proved to be effective in vivo. Compound 1e is an interesting potential therapeutic agent in IMIDs.


Assuntos
Anti-Inflamatórios/síntese química , Benzimidazóis/síntese química , Desenho de Fármacos , Indóis/síntese química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/toxicidade , Benzimidazóis/química , Benzimidazóis/farmacologia , Benzimidazóis/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Indóis/química , Indóis/farmacologia , Indóis/toxicidade , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Estrutura Molecular , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Cultura Primária de Células , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores
16.
PLoS One ; 9(10): e109981, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25299159

RESUMO

In this study, we investigated the reverse transcriptase subunit of telomerase in the dimorphic fungus Ustilago maydis. This protein (Trt1) contains 1371 amino acids and all of the characteristic TERT motifs. Mutants created by disrupting trt1 had senescent traits, such as delayed growth, low replicative potential, and reduced survival, that were reminiscent of the traits observed in est2 budding yeast mutants. Telomerase activity was observed in wild-type fungus sporidia but not those of the disruption mutant. The introduction of a self-replicating plasmid expressing Trt1 into the mutant strain restored growth proficiency and replicative potential. Analyses of trt1 crosses in planta suggested that Trt1 is necessary for teliospore formation in homozygous disrupted diploids and that telomerase is haploinsufficient in heterozygous diploids. Additionally, terminal restriction fragment analysis in the progeny hinted at alternative survival mechanisms similar to those of budding yeast.


Assuntos
Telomerase/biossíntese , Telomerase/genética , Ustilago/enzimologia , Sequência de Aminoácidos , Replicação do DNA/genética , Diploide , Regulação Fúngica da Expressão Gênica , Esporos/genética , Telomerase/isolamento & purificação , Ustilago/genética , Ustilago/crescimento & desenvolvimento
17.
Enferm. glob ; 13(33): 252-266, ene. 2014. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-118494

RESUMO

Introducción: El síndrome de Burnout aparece cuando se mantiene una relación de ayuda con una relación interpersonal intensa con los beneficiarios del trabajo. En numerosos estudios se ha considerado al personal de enfermería como grupo vulnerable. Algunos estudios revelan que las unidades que generan mayor estrés son aquellas que reúnen pacientes críticos o terminales. El ambiente laboral de estas unidades, las continuas demandas físicas y emocionales a las que las enfermeras se ven sometidas por parte de los pacientes y la ambigüedad en su rol son características que predisponen al desarrollo de dicho síndrome. Objetivos: El objetivo principal es determinar el grado de Burnout en el equipo de enfermería de la UVI médica del hospital Ramón y Cajal. Material y métodos: Muestra de 68 enfermeros y auxiliares que trabajan en la UVI. Como instrumento, se utiliza el cuestionario Maslach Burnout Inventory en su versión en español, de manera autoadministrada. Resultados: Bajas puntuaciones en las tres dimensiones del síndrome (cansancio emocional, despersonalización y realización personal), y la mayoría de la población, un 45,6%, tendencia a padecerlo. Conclusiones: El perfil del trabajador que padece síndrome de Burnout sería: enfermera, de 35 a 44 años, con contrato fijo, experiencia laboral mayor de 16 años y una antigüedad de 1 a 5 años en el puesto de trabajo (AU)


Introduction: The burnout syndrome occurs when a supportive relationship is maintained with a strong interpersonal relationship with the beneficiaries of that work. Several studies have considered the nursing staff as a fragile group. Some studies revealed that units that generate greater stress are those that meet critical or terminal patients: the environment, physical and emotional continuing demands to the nurses who are subjected by patients, and role ambiguity are characteristics that predispose the development of this syndrome. Objectives: The main objective is to determine the degree of burnout in the team ICU nursing Hospital Medical Ramón y Cajal. Material and methods: Sample of 68 nurses and assistants working in the ICU. As an instrument, we used Maslach Burnout Inventory in its Spanish version, self administered. Results: Low scores on the three dimensions of the syndrome (emotional exhaustion, depersonalization and personal accomplishment), and most sample with a 45.6%, tendency to suffer. Conclusions: Profile of workers suffering burnout is: nurse, 35 to 44 years, with contract fixed, experience over 16 years and an age of 1-5 years in that job (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Relações Interpessoais , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/enfermagem , Estresse Psicológico/enfermagem , Inquéritos e Questionários , 16360 , Esgotamento Profissional/fisiopatologia , Esgotamento Profissional/psicologia , Estudos Transversais/métodos
18.
Org Lett ; 15(13): 3388-91, 2013 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-23795915

RESUMO

The reaction of alkyl tosylmethyl isocyanides and 2-bromobenzyl bromides in the presence of t-BuLi gives rise to a cascade reaction to give unexpected 2-substituted 2,3-dihydro-1H-indenimines which, upon treatment with t-BuOK, rearrange to 2-vinylbenzonitriles in high overall yields. This simple procedure represents a new approach to the synthesis of aromatic nitriles via isocyanide-cyanide interconversion.

19.
Eur J Med Chem ; 50: 90-101, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22336384

RESUMO

We report new examples of a series of losartan-hydrocaffeic hybrids that bear novel ester, amide and amine linkers. These compounds were made by linking hydrocaffeic acid to the side chain of losartan at the C-5 position of the imidazole ring through different strategies. Experiments performed in cultured cells demonstrate that these new hybrids retain the ability to block the angiotensin II effect and have increased antioxidant ability. Most of them reduced arterial pressure in rats better or as much as losartan.


Assuntos
Anti-Hipertensivos/síntese química , Anti-Hipertensivos/farmacologia , Antioxidantes/síntese química , Antioxidantes/farmacologia , Ácidos Cafeicos/química , Losartan/química , Amidas/química , Amidas/metabolismo , Aminas/química , Aminas/metabolismo , Angiotensina II/farmacologia , Animais , Aorta Torácica/citologia , Aorta Torácica/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Células Cultivadas , Ésteres/química , Ésteres/metabolismo , Hipertensão/tratamento farmacológico , Losartan/farmacologia , Masculino , Estrutura Molecular , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Vasoconstritores/farmacologia
20.
Braz. j. microbiol ; 41(3): 749-756, Oct. 2010. graf, tab
Artigo em Inglês | LILACS | ID: lil-549417

RESUMO

Cervical cancer is an important health problem in women living in developing countries. Infection with some genotypes of human papillomavirus (HPV) is the most important risk factor associated with cervical cancer. Little information exists about HPV genotype distribution in rural and suburban regions of Mexico. Thus, we determined the prevalence of HPV genotypes in women from Tlaxcala, one of the poorest states in central Mexico, and we evaluated age infection prevalence and risk factors associated with cervical neoplasm. A cross-sectional study was conducted in 236 women seeking gynecological care at the Mexican Institute for Social Security in Tlaxcala, Mexico. Cervical scrapings were diagnosed as normal, low-grade, and high-grade squamous intraepithelial lesions (LGSIL, HGSIL). Parallel samples were used to detect HPV genotypes by PCR assays using type-specific primers for HPV 6, 11, 16, 18, and 31. An epidemiological questionnaire was applied. Prevalence of HPV infection was 31.3 percent. From the infected samples, prevalence of HPV 16 was 45.9 percent; HPV 18, 31.1 percent; HPV 31, 16.2 percent; HPV 6, 10.8 percent; HPV 11, 6.7 percent. With regard to age, the highest HPV prevalence (43.5 percent) was found in the 18- to 24-year-old group and the lowest (19 percent) in the 45- to 54-year-old group. None of the risk factors showed association with cervical neoplasia grade. HPV 16 was the most common in cervical lesions. HPV was present in 22 percent of normal samples and, of these, 82.6 percent represented high-risk HPVs. Tlaxcala showed HPV prevalence comparable to that of the largest cities in Mexico, with higher prevalence for HPV 31.


Assuntos
Humanos , Feminino , Adulto , Reação em Cadeia do Fogo , Técnicas In Vitro , Infecções por Papillomavirus , Papillomaviridae/isolamento & purificação , Papillomaviridae/patogenicidade , Métodos Epidemiológicos , Genótipo , Prevalência , Fatores de Risco , Métodos
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