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1.
Infect Immun ; 91(8): e0004223, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37404186

RESUMO

Patients receiving the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib have an increased likelihood of fungal infections. The objectives of this study were to determine if Cryptococcus neoformans infection severity was isolate dependent with BTK inhibition and whether blocking BTK impacted infection severity in a mouse model. We compared four clinical isolates from patients on ibrutinib to virulent (H99) and avirulent (A1-35-8) reference strains. BTK knockout (KO) and wild-type (WT) C57 mice and WT CD1 mice were infected by intranasal (i.n.), oropharyngeal aspiration (OPA), and intravenous (i.v.) routes. Infection severity was assessed by survival and fungal burden (CFU per gram of tissue). Ibrutinib (25 mg/kg) or vehicle was administered daily through intraperitoneal injections. In the BTK KO model, no isolate-dependent effect on fungal burden was observed, and infection severity was not significantly different from that of the WT with i.n., OPA, and i.v. routes. Ibrutinib treatment did not impact infection severity. However, when the four clinical isolates were compared to H99, two of these isolates were less virulent, with significantly longer survival and reduced rates of brain infection. In conclusion, C. neoformans infection severity in the BTK KO model does not appear to be isolate dependent. BTK KO and ibrutinib treatment did not result in significantly different infection severities. However, based on repeated clinical observations of increased susceptibility to fungal infections with BTK inhibitor therapy, further work is needed to optimize a mouse model with BTK inhibition to better understand the role that this pathway plays in susceptibility to C. neoformans infection.


Assuntos
Criptococose , Camundongos , Animais , Tirosina Quinase da Agamaglobulinemia/metabolismo , Criptococose/tratamento farmacológico , Encéfalo/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
2.
Trop Anim Health Prod ; 54(3): 196, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35654900

RESUMO

The present study evaluated the metabolic and functional effects of adding garra meal to a broiler chicken diet. Three hundred twenty Sasso-breed day-old chicks were randomly assigned to four dietary treatments with either 0, 10, 20 or 30% garra meal added on top of formulated starter and grower basal diets. The experiment lasted for 42 days. Feed intake and body weight gain increased at the starter and grower phases of broilers with garra meal addition (P < 0.05). Broiler chickens fed 30% garra meal were more efficient in converting feed to body weight and yielded the highest carcass weight (P < 0.05). Crude protein ileal digestibility coefficient was higher with 20% (76.2%), and crude fat with 20 (92.1) and 30% (92.6%) garra meal receiving groups (P < 0.05). The increase in individual and total esterified carnitine concentrations in dried blood spots demonstrated the elevated metabolic rate with garra meal addition (P < 0.05). A better supply of glucogenic substrate to the citric acid cycle was seen with garra meal addition due to the increase of propionylcarnitine to acetylcarnitine ratio (P < 0.05) without any apparent effect on ketogenesis in terms of serum 3-hydroxybutyrylcarnitine to acetylcarnitine ratio. Yet, it likely showed that part of the amino acids from garra meal were used as glucogenic substrate (P < 0.05). Histomorphometry data showed 20% garra meal addition elevated villus height, crypt depth and their ratio in the proximal parts of the small intestine (duodenum and jejunum) with the opposite results observed in the more distal part (ileum) with the highest for the control group (P < 0.05). It can be concluded that garra meal improved broiler performance when added to a plant-based diet and only few parameters warranted for caution when using more up to 30% garra meal addition. Beyond growth performance, garra meal generated a shift to a more efficient digestion, absorption and nutrient metabolism.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas , Acetilcarnitina/farmacologia , Ração Animal/análise , Animais , Dieta/veterinária , Peixes , Aumento de Peso
3.
Antimicrob Agents Chemother ; 65(10): e0068221, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34310205

RESUMO

Invasive aspergillosis (IA) due to Aspergillus fumigatus is a deadly infection for which new antifungal therapies are needed. Here, we demonstrate the efficacy of a Gwt1 inhibitor, APX2041, and its prodrug, APX2104, against A. fumigatus. The wild-type, azole-resistant, and echinocandin-resistant A. fumigatus strains were equally susceptible to APX2041 in vitro. APX2104 treatment in vivo significantly prolonged survival of neutropenic mice challenged with the wild-type and azole-resistant strains, revealing APX2104 as a potentially promising therapeutic against IA.


Assuntos
Aspergillus fumigatus , Pró-Fármacos , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Farmacorresistência Fúngica/genética , Isoxazóis , Camundongos , Testes de Sensibilidade Microbiana , Pró-Fármacos/farmacologia
4.
Trop Anim Health Prod ; 53(1): 54, 2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33389207

RESUMO

Poultry production contributes significantly to the livelihoods of Ethiopian farmers and to the national economy although it is hampered by different factors, including poultry diseases. There is scarcity of published evidences on the occurrence and impacts of poultry diseases although such evidences are important for policy makers in designing appropriate interventions. A total of 595 households were interviewed and 11 FGDs were conducted to collect data on the occurrence of diseases and the number of dead chickens in the last 12 months. Hence, respiratory diseases, sudden death, and eye-face-head diseases were mentioned in all of the FGDs as the most frequently occurring disease in the districts. Of households interviewed, 86.1% reported poultry disease occurrence in the last 12 months, and gastrointestinal, eye-face-head, and neurological diseases were identified to be the top three ranked diseases of chickens in the districts. Flocks with access to diagnostic services (Adj. OR = 4.16; P = 0.004) and/or access to animal health providers (Adj. OR = 10.50; P = 0.001) were more likely to report disease occurrence. In the studied population, the diseases resulted in deaths of 2219 chickens valued at 352,219.5 Birr (11,740.65 USD) and a mean crude mortality of 31.87%. Female-lead households (mean difference = 5.95%; P = 0.018) and multiple age units present on the farm (mean difference = 20.92%; P = < 0.000) had higher chicken mortality. Similarly, higher mortality was reported in flocks without access to diagnosis (mean difference = 9.97%; P = < 0.000) and vaccination (mean difference = 12.34%; P = < 0.000) services. The high occurrence of disease and mortalities might be explained by a lack of an organized poultry health service delivery system in the country. Therefore, a carefully designed health service delivery system addressing needs of poultry producers, supported by relevant policy and corresponding strategies, is recommended to address the indicated challenges. Moreover, private health providers with well-defined roles need to be engaged to successfully and sustainably solve the poultry disease problems.


Assuntos
Galinhas , Fazendas/estatística & dados numéricos , Doenças das Aves Domésticas/mortalidade , Criação de Animais Domésticos , Animais , Estudos Transversais , Etiópia/epidemiologia , Características da Família , Fazendeiros , Fazendas/economia , Feminino , Humanos , Aves Domésticas , Doenças das Aves Domésticas/economia , Produtos Avícolas , Vacinação/veterinária
5.
Mol Microbiol ; 112(1): 62-80, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30927289

RESUMO

Calcium signaling through calcineurin and its major transcription factor (TF), CrzA, is integral to hyphal growth, stress response and virulence of the pathogenic fungus Aspergillus fumigatus, the leading etiology of invasive aspergillosis. Dephosphorylation of CrzA by calcineurin activates the TF, but the specific phosphorylation sites and their roles in the activation/inactivation mechanism are unknown. Mass spectroscopic analysis identified 20 phosphorylation sites, the majority of which were specific to filamentous fungi and distributed throughout the CrzA protein, with particular concentration in a serine-rich region N-terminal to the conserved DNA-binding domain (DBD). Site-directed mutagenesis of phosphorylated residues revealed that CrzA activity during calcium stimulation can only be suppressed by a high degree of phosphorylation in multiple regions of the protein. Our findings further suggest that this regulation is not solely accomplished through control of CrzA nuclear import. Additionally, we demonstrate the importance of the CrzA phosphorylation state in regulating growth, conidiation, calcium and cell wall stress tolerance, and virulence. Finally, we identify two previously undescribed nuclear localization sequences in the DBD. These findings provide novel insight into the phosphoregulation of CrzA which may be exploited to selectively target A. fumigatus.


Assuntos
Aspergillus fumigatus/metabolismo , Proteínas Fúngicas/metabolismo , Transporte Ativo do Núcleo Celular , Aspergilose/microbiologia , Aspergillus fumigatus/genética , Calcineurina/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/genética , Espectrometria de Massas/métodos , Mutagênese Sítio-Dirigida , Fosforilação , Estresse Fisiológico , Fatores de Transcrição/metabolismo , Virulência/fisiologia
6.
Med Mycol ; 58(8): 1149-1161, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32196550

RESUMO

We previously observed a substantial burden of cryptococcal meningitis in Vietnam atypically arising in individuals who are uninfected with human immunodeficiency virus (HIV). This disease was associated with a single genotype of Cryptococcus neoformans (sequence type [ST]5), which was significantly less common in HIV-infected individuals. Aiming to compare the phenotypic characteristics of ST5 and non-ST5 C. neoformans, we selected 30 representative Vietnamese isolates and compared their in vitro pathogenic potential and in vivo virulence. ST5 and non-ST5 organisms exhibited comparable characteristics with respect to in vitro virulence markers including melanin production, replication at 37°C, and growth in cerebrospinal fluid. However, the ST5 isolates had significantly increased variability in cellular and capsular sizing compared with non-ST5 organisms (P < .001). Counterintuitively, mice infected with ST5 isolates had significantly longer survival with lower fungal burdens at day 7 than non-ST5 isolates. Notably, ST5 isolates induced significantly greater initial inflammatory responses than non-ST5 strains, measured by TNF-α concentrations (P < .001). Despite being generally less virulent in the mouse model, we hypothesize that the significant within strain variation seen in ST5 isolates in the tested phenotypes may represent an evolutionary advantage enabling adaptation to novel niches including apparently immunocompetent human hosts.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Cryptococcus neoformans/patogenicidade , Meningite Criptocócica/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/patologia , Animais , Contagem de Colônia Microbiana , Cryptococcus neoformans/genética , Citocinas/metabolismo , Feminino , Cápsulas Fúngicas/patologia , Genótipo , Humanos , Imunocompetência , Pulmão/metabolismo , Pulmão/microbiologia , Pulmão/patologia , Masculino , Meningite Criptocócica/patologia , Camundongos , Fenótipo , Vietnã/epidemiologia , Virulência
7.
J Inherit Metab Dis ; 41(6): 965-976, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30043186

RESUMO

BACKGROUND: Glycogen storage disease type Ia (GSD Ia) in dogs closely resembles human GSD Ia. Untreated patients with GSD Ia develop complications associated with glucose-6-phosphatase (G6Pase) deficiency. Survival of human patients on intensive nutritional management has improved; however, long-term complications persist including renal failure, nephrolithiasis, hepatocellular adenomas (HCA), and a high risk for hepatocellular carcinoma (HCC). Affected dogs fail to thrive with dietary therapy alone. Treatment with gene replacement therapy using adeno-associated viral vectors (AAV) expressing G6Pase has greatly prolonged life and prevented hypoglycemia in affected dogs. However, long-term complications have not been described to date. METHODS: Five GSD Ia-affected dogs treated with AAV-G6Pase were evaluated. Dogs were euthanized due to reaching humane endpoints related to liver and/or kidney involvement, at 4 to 8 years of life. Necropsies were performed and tissues were analyzed. RESULTS: Four dogs had liver tumors consistent with HCA and HCC. Three dogs developed renal failure, but all dogs exhibited progressive kidney disease histologically. Urolithiasis was detected in two dogs; uroliths were composed of calcium oxalate and calcium phosphate. One affected and one carrier dog had polycystic ovarian disease. Bone mineral density was not significantly affected. CONCLUSIONS: Here, we show that the canine GSD Ia model demonstrates similar long-term complications as GSD Ia patients in spite of gene replacement therapy. Further development of gene therapy is needed to develop a more effective treatment to prevent long-term complications of GSD Ia.


Assuntos
Carcinoma Hepatocelular/etiologia , Terapia Genética , Doença de Depósito de Glicogênio Tipo I/complicações , Doença de Depósito de Glicogênio Tipo I/terapia , Neoplasias Hepáticas/etiologia , Animais , Dependovirus/genética , Modelos Animais de Doenças , Cães , Feminino , Vetores Genéticos , Glucose-6-Fosfatase/genética , Glucose-6-Fosfatase/metabolismo , Hipoglicemia/genética , Hipoglicemia/metabolismo , Fígado/patologia , Masculino
8.
Infect Immun ; 84(5): 1556-64, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26953327

RESUMO

Myosins are a family of actin-based motor proteins found in many organisms and are categorized into classes based on their structures. Class II and V myosins are known to be important for critical cellular processes, including cytokinesis, endocytosis, exocytosis, and organelle trafficking, in the model fungi Saccharomyces cerevisiae and Aspergillus nidulans However, the roles of myosins in the growth and virulence of the pathogen Aspergillus fumigatus are unknown. We constructed single- and double-deletion strains of the class II and class V myosins in A. fumigatus and found that while the class II myosin (myoB) is dispensable for growth, the class V myosin (myoE) is required for proper hyphal extension; deletion of myoE resulted in hyperbranching and loss of hyphal polarity. Both myoB and myoE are necessary for proper septation, conidiation, and conidial germination, but only myoB is required for conidial viability. Infection with the ΔmyoE strain in the invertebrate Galleria mellonella model and also in a persistently immunosuppressed murine model of invasive aspergillosis resulted in hypovirulence, while analysis of bronchoalveolar lavage fluid revealed that tumor necrosis factor alpha (TNF-α) release and cellular infiltration were similar compared to those of the wild-type strain. The ΔmyoE strain showed fungal growth in the murine lung, while the ΔmyoB strain exhibited little fungal burden, most likely due to the reduced conidial viability. These results show, for the first time, the important role these cytoskeletal components play in the growth of and disease caused by a known pathogen, prompting future studies to understand their regulation and potential targeting for novel antifungal therapies.


Assuntos
Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/patogenicidade , Proteínas Fúngicas/metabolismo , Hifas/crescimento & desenvolvimento , Miosinas/metabolismo , Animais , Aspergilose/microbiologia , Aspergilose/patologia , Aspergillus fumigatus/genética , Contagem de Colônia Microbiana , Proteínas Fúngicas/genética , Técnicas de Inativação de Genes , Pulmão/microbiologia , Masculino , Camundongos , Viabilidade Microbiana , Miosinas/deficiência , Esporos Fúngicos/crescimento & desenvolvimento , Virulência
9.
PLoS Pathog ; 9(8): e1003564, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23990785

RESUMO

The fungus Aspergillus fumigatus is a leading infectious killer in immunocompromised patients. Calcineurin, a calmodulin (CaM)-dependent protein phosphatase comprised of calcineurin A (CnaA) and calcineurin B (CnaB) subunits, localizes at the hyphal tips and septa to direct A. fumigatus invasion and virulence. Here we identified a novel serine-proline rich region (SPRR) located between two conserved CnaA domains, the CnaB-binding helix and the CaM-binding domain, that is evolutionarily conserved and unique to filamentous fungi and also completely absent in human calcineurin. Phosphopeptide enrichment and tandem mass spectrometry revealed the phosphorylation of A. fumigatus CnaA in vivo at four clustered serine residues (S406, S408, S410 and S413) in the SPRR. Mutation of the SPRR serine residues to block phosphorylation led to significant hyphal growth and virulence defects, indicating the requirement of calcineurin phosphorylation at the SPRR for its activity and function. Complementation analyses of the A. fumigatus ΔcnaA strain with cnaA homologs from the pathogenic basidiomycete Cryptococcus neoformans, the pathogenic zygomycete Mucor circinelloides, the closely related filamentous fungi Neurospora crassa, and the plant pathogen Magnaporthe grisea, revealed filamentous fungal-specific phosphorylation of CnaA in the SPRR and SPRR homology-dependent restoration of hyphal growth. Surprisingly, circular dichroism studies revealed that, despite proximity to the CaM-binding domain of CnaA, phosphorylation of the SPRR does not alter protein folding following CaM binding. Furthermore, mutational analyses in the catalytic domain, CnaB-binding helix, and the CaM-binding domains revealed that while the conserved PxIxIT substrate binding motif in CnaA is indispensable for septal localization, CaM is required for its function at the hyphal septum but not for septal localization. We defined an evolutionarily conserved novel mode of calcineurin regulation by phosphorylation in filamentous fungi in a region absent in humans. These findings suggest the possibility of harnessing this unique SPRR for innovative antifungal drug design to combat invasive aspergillosis.


Assuntos
Aspergillus fumigatus/enzimologia , Calcineurina/metabolismo , Proteínas Fúngicas/metabolismo , Hifas/enzimologia , Modelos Biológicos , Motivos de Aminoácidos , Animais , Antifúngicos/química , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/enzimologia , Aspergilose/genética , Aspergillus fumigatus/genética , Calcineurina/química , Calcineurina/imunologia , Inibidores de Calcineurina , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Humanos , Hifas/genética , Masculino , Camundongos , Fosforilação , Estrutura Terciária de Proteína
10.
J Infect Dis ; 209(3): 473-81, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24096332

RESUMO

Invasive aspergillosis is a deadly infection for which new antifungal therapies are needed. Heat shock protein 90 (Hsp90) is an essential chaperone in Aspergillus fumigatus representing an attractive antifungal target. Using a thiamine-repressible promoter (pthiA), we showed that genetic repression of Hsp90 significantly reduced virulence in a murine model of invasive aspergillosis. Moreover, substituting the A. fumigatus hsp90 promoter with 2 artificial promoters (potef, pthiA) and the Candida albicans hsp90 promoter resulted in hypersensitivity to caspofungin and abolition of the paradoxical effect (resistance at high caspofungin concentrations). By inducing truncations in the hsp90 promoter, we identified a 100-base pair proximal sequence that triggers a significant increase of hsp90 expression (≥1.5-fold) and is essential for the paradoxical effect. Preventing this increase of hsp90 expression was sufficient to abolish the paradoxical effect and therefore optimize the antifungal activity of caspofungin.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Proteínas de Choque Térmico HSP90/biossíntese , Regiões Promotoras Genéticas , Ativação Transcricional , Animais , Antifúngicos/uso terapêutico , Aspergillus fumigatus/genética , Caspofungina , Modelos Animais de Doenças , Equinocandinas/uso terapêutico , Lipopeptídeos , Masculino , Camundongos , Aspergilose Pulmonar/tratamento farmacológico , Aspergilose Pulmonar/microbiologia , Aspergilose Pulmonar/patologia
11.
Infect Immun ; 82(2): 683-93, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24478083

RESUMO

Cryptococcus neoformans is an opportunistic fungal pathogen that initiates infection following inhalation. As a result, the pulmonary immune response provides a first line of defense against C. neoformans. Surfactant protein D (SP-D) is an important regulator of pulmonary immune responses and is typically host protective against bacterial and viral respiratory infections. However, SP-D is not protective against C. neoformans. This is evidenced by previous work from our laboratory demonstrating that SP-D-deficient mice infected with C. neoformans have a lower fungal burden and live longer than wild-type (WT) control animals. We hypothesized that SP-D alters susceptibility to C. neoformans by dysregulating the innate pulmonary immune response following infection. Thus, inflammatory cells and cytokines were compared in the bronchoalveolar lavage fluid from WT and SP-D(-/-) mice after C. neoformans infection. Postinfection, mice lacking SP-D have reduced eosinophil infiltration and interleukin-5 (IL-5) in lung lavage fluid. To further explore the interplay of SP-D, eosinophils, and IL-5, mice expressing altered levels of eosinophils and/or IL-5 were infected with C. neoformans to assess the role of these innate immune mediators. IL-5-overexpressing mice have increased pulmonary eosinophilia and are more susceptible to C. neoformans infection than WT mice. Furthermore, susceptibility of SP-D(-/-) mice to C. neoformans infection could be restored to the level of WT mice by increasing IL-5 and eosinophils by crossing the IL-5-overexpressing mice with SP-D(-/-) mice. Together, these studies support the conclusion that SP-D increases susceptibility to C. neoformans infection by promoting C. neoformans-driven pulmonary IL-5 and eosinophil infiltration.


Assuntos
Criptococose/imunologia , Criptococose/patologia , Cryptococcus neoformans/imunologia , Eosinofilia/imunologia , Interleucina-5/imunologia , Proteína D Associada a Surfactante Pulmonar/imunologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Modelos Animais de Doenças , Feminino , Pulmão/imunologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína D Associada a Surfactante Pulmonar/deficiência
12.
Antimicrob Agents Chemother ; 58(4): 1889-96, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24395240

RESUMO

Heat shock protein 90 (Hsp90) is an essential chaperone involved in the fungal stress response that can be harnessed as a novel antifungal target for the treatment of invasive aspergillosis. We previously showed that genetic repression of Hsp90 reduced Aspergillus fumigatus virulence and potentiated the effect of the echinocandin caspofungin. In this study, we sought to identify sites of posttranslational modifications (phosphorylation or acetylation) that are important for Hsp90 function in A. fumigatus. Phosphopeptide enrichment and tandem mass spectrometry revealed phosphorylation of three residues in Hsp90 (S49, S288, and T681), but their mutation did not compromise Hsp90 function. Acetylation of lysine residues of Hsp90 was recovered after treatment with deacetylase inhibitors, and acetylation-mimetic mutations (K27A and K271A) resulted in reduced virulence in a murine model of invasive aspergillosis, supporting their role in Hsp90 function. A single deletion of lysine K27 or an acetylation-mimetic mutation (K27A) resulted in increased susceptibility to voriconazole and caspofungin. This effect was attenuated following a deacetylation-mimetic mutation (K27R), suggesting that this site is crucial and should be deacetylated for proper Hsp90 function in antifungal resistance pathways. In contrast to previous reports in Candida albicans, the lysine deacetylase inhibitor trichostatin A (TSA) was active alone against A. fumigatus and potentiated the effect of caspofungin against both the wild type and an echinocandin-resistant strain. Our results indicate that the Hsp90 K27 residue is required for azole and echinocandin resistance in A. fumigatus and that deacetylase inhibition may represent an adjunctive anti-Aspergillus strategy.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/metabolismo , Azóis/farmacologia , Equinocandinas/farmacologia , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/metabolismo , Lisina/química , Aspergillus fumigatus/genética , Caspofungina , Farmacorresistência Fúngica/genética , Proteínas de Choque Térmico HSP90/genética , Lipopeptídeos , Lisina/genética
13.
PLoS One ; 19(4): e0299926, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625887

RESUMO

Preservation of fish as diet ingredient is challenging in many tropical regions due to poor socioeconomic conditions and lack of freezing facilities. So, alternative preservation techniques could be viable to address the issue. The present study evaluated the effect of brine salting (15% w/v) prior to drying at different temperatures on the nutrient profiles of tambaqui fish (Colossoma macropomum). Whole fish samples (n = 48; 792 ± 16 g; 8 months old) were grouped into two as brine-salted and non-salted, and treated at seven different drying temperatures of 30, 35, 40, 45, 50, 55 and 60°C for a period of 23 h each. To evaluate the impact of Maillard reaction, reactive lysine was also quantified. Drying temperature had no effect on the evaluated macro- and micro-nutrients of tambaqui fish (P > 0.05) while brining reduced the overall protein concentration by 6% (58.8 to 55.4 g/100 g DM; P = 0.004). Brining significantly reduced many amino acids: taurine by 56% (7.1 to 3.1 g/kg; P < 0.001), methionine 17% (14.7 to 12.1 g/kg; P < 0.001), cysteine 11% (5.1 to 4.4 g/kg, P = 0.016), and reactive lysine 11% (52.0 to 46.4 g/kg; P = 0.004). However, alanine, arginine, and serine were not affected by brining (P > 0.05). Brining also reduced the concentrations of Se by 14% (149 to 128 µg/kg DM; P = 0.020), iodine 38% (604 to 373 µg/kg DM; P = 0.020), K 42% (9.71 to 5.61 g/kg DM; P < 0.001) and Mg 18% (1.32 to 1.10 g/kg DM; P = < 0.001) versus an anticipated vast increase in Na by 744% (2.70 to 22.90 g/kg DM; P < 0.001) and ash 28% (12.4 to 16.0 g/100g DM; P < 0.001) concentration. Neither brining nor drying temperature induced changes in % lysine reactivity and fat content of tambaqui fish (P > 0.05). Agreeably, results of multivariate analysis showed a negative association between brining, Na, and ash on one side of the component and most other nutrients on the other component. In conclusion, drying without brining may better preserve the nutritive value of tambaqui fish. However, as a practical remark to the industry sector, it is recommended that the final product may further evaluated for any pathogen of economic or public health importance.


Assuntos
Caraciformes , Lisina , Animais , Lisina/metabolismo , Caraciformes/metabolismo , Sais/metabolismo , Valor Nutritivo
14.
mBio ; 15(5): e0064924, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38619236

RESUMO

Invasive fungal infections are a significant public health concern, with mortality rates ranging from 20% to 85% despite current treatments. Therefore, we examined whether a ketogenic diet could serve as a successful treatment intervention in murine models of Cryptococcus neoformans and Candida albicans infection in combination with fluconazole-a low-cost, readily available antifungal therapy. The ketogenic diet is a high-fat, low-carbohydrate diet that promotes fatty acid oxidation as an alternative to glycolysis through the production of ketone bodies. In this series of experiments, mice fed a ketogenic diet prior to infection with C. neoformans and treated with fluconazole had a significant decrease in fungal burden in both the brain (mean 2.66 ± 0.289 log10 reduction) and lung (mean 1.72 ± 0.399 log10 reduction) compared to fluconazole treatment on a conventional diet. During C. albicans infection, kidney fungal burden of mice in the keto-fluconazole combination group was significantly decreased compared to fluconazole alone (2.37 ± 0.770 log10-reduction). Along with higher concentrations of fluconazole in the plasma and brain tissue, fluconazole efficacy was maximized at a significantly lower concentration on a keto diet compared to a conventional diet, indicating a dramatic effect on fluconazole pharmacodynamics. Our findings indicate that a ketogenic diet potentiates the effect of fluconazole at multiple body sites during both C. neoformans and C. albicans infection and could have practical and promising treatment implications.IMPORTANCEInvasive fungal infections cause over 2.5 million deaths per year around the world. Treatments for fungal infections are limited, and there is a significant need to develop strategies to enhance antifungal efficacy, combat antifungal resistance, and mitigate treatment side effects. We determined that a high-fat, low-carbohydrate ketogenic diet significantly potentiated the therapeutic effect of fluconazole, which resulted in a substantial decrease in tissue fungal burden of both C. neoformans and C. albicans in experimental animal models. We believe this work is the first of its kind to demonstrate that diet can dramatically influence the treatment of fungal infections. These results highlight a novel strategy of antifungal drug enhancement and emphasize the need for future investigation into dietary effects on antifungal drug activity.


Assuntos
Antifúngicos , Candida albicans , Candidíase , Criptococose , Cryptococcus neoformans , Dieta Cetogênica , Modelos Animais de Doenças , Fluconazol , Animais , Fluconazol/farmacologia , Fluconazol/administração & dosagem , Camundongos , Antifúngicos/administração & dosagem , Antifúngicos/farmacologia , Candidíase/tratamento farmacológico , Candidíase/dietoterapia , Candidíase/microbiologia , Candida albicans/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Criptococose/dietoterapia , Criptococose/prevenção & controle , Feminino , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Pulmão/microbiologia , Pulmão/efeitos dos fármacos
15.
Eukaryot Cell ; 11(8): 966-77, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22562470

RESUMO

Ras is a highly conserved GTPase protein that is essential for proper polarized morphogenesis of filamentous fungi. Localization of Ras proteins to the plasma membrane and endomembranes through posttranslational addition of farnesyl and palmitoyl residues is an important mechanism through which cells provide specificity to Ras signal output. Although the Aspergillus fumigatus RasA protein is known to be a major regulator of growth and development, the membrane distribution of RasA during polarized morphogenesis and the role of properly localized Ras signaling in virulence of a pathogenic mold remain unknown. Here we demonstrate that Aspergillus fumigatus RasA localizes primarily to the plasma membrane of actively growing hyphae. We show that treatment with the palmitoylation inhibitor 2-bromopalmitate disrupts normal RasA plasma membrane association and decreases hyphal growth. Targeted mutations of the highly conserved RasA palmitoylation motif also mislocalized RasA from the plasma membrane and led to severe hyphal abnormalities, cell wall structural changes, and reduced virulence in murine invasive aspergillosis. Finally, we provide evidence that proper RasA localization is independent of the Ras palmitoyltransferase homolog, encoded by erfB, but requires the palmitoyltransferase complex subunit, encoded by erfD. Our results demonstrate that plasma membrane-associated RasA is critical for polarized morphogenesis, cell wall stability, and virulence in A. fumigatus.


Assuntos
Aspergillus fumigatus/metabolismo , Proteínas Fúngicas/metabolismo , Morfogênese , Proteínas ras/metabolismo , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Aspergillus fumigatus/genética , Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/patogenicidade , Membrana Celular/metabolismo , Proteínas Fúngicas/genética , Hifas/genética , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Lipoilação , Dados de Sequência Molecular , Morfogênese/genética , Mutação , Palmitatos/farmacologia , Processamento de Proteína Pós-Traducional , Transporte Proteico , Serina C-Palmitoiltransferase/antagonistas & inibidores , Serina C-Palmitoiltransferase/genética , Serina C-Palmitoiltransferase/metabolismo , Virulência/genética , Proteínas ras/genética
16.
Heliyon ; 9(12): e22682, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38076201

RESUMO

For a long time, co-products of food processing have been used in animal feed, but far less in fish because of their assumed inability to cope with high-fiber diets. Research on feeding co-products to fish species that naturally consume fibrous diets are yet lacking. We here evaluated the impact of sugar beet pulp in the diet of tambaquí on nutrient metabolism, oxidative stress, inflammation, and intestinal histomorphometry. A total of 18 tambaquí fish (1616 ± 107 g; 2 years old) were randomly divided over 6 similar tanks with 3 fish per tank and randomly attributed to one of the six dietary treatments 0, 5, 10, 15, 20 and 25 % beet pulp addition and reared for 8 weeks. Water quality parameters (pH, NH3-N, EC, TDS, DO, and temperature) were assessed and recorded twice a week for each tank. A quadratic increase in intestinal villus length, paravilli and absorptive surface were observed with beet pulp addition. Ammonia and pH as quality indicators were significantly changing with beet pulp addition. A higher supply of glucogenic substrate to the citric acid cycle was noticed with beet pulp addition due to the positive correlation with blood propionylcarnitine: acetylcarnitine ratio while there was no effect on ketone body synthesis as measured through the 3-hydroxybutyrylcarnitine: acetylcarnitine ratio. No pronounced change of serum and whole fish histamine and lowered concentrations of serum malondialdehyde were observed with beet pulp addition. In conclusion, beet pulp induced a marked increase in intestinal villus architecture without signs of inflammation or oxidative stress. Large-scale studies need to clarify if these features lead to improved growth performance but this work opens options for further study. The non-linear pattern of some blood components with increasing beet pulp may call for future optimal dosing and feed form of beet pulp together.

17.
Front Vet Sci ; 9: 735269, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35274017

RESUMO

Public-private partnerships (PPPs) in the veterinary domain are joint approaches in which public veterinary services and private actors such as private veterinarians, producers' associations, or private companies work together to address complex animal health challenges. They are implemented worldwide and can help to strengthen the capacities of veterinary services, but few have been evaluated. None of the evaluations developed in the veterinary domain explicitly addressed PPPs, their complex program design, their evolving governance, and coordination system, and their impacts. This work represents the first application of the participatory impact pathway methodology for the evaluation of a PPP in the veterinary domain. The PPP evaluated aimed at developing the poultry sector in Ethiopia and improving poultry health service coverage, particularly in remote areas. The combination of semi-structured interviews (n = 64) and collective reflection during three workshops (n participants = 26, 48, 18), captured the viewpoints of public and private partners, actors who influenced the partnership, and actors impacted by it. The context of the PPP was analyzed, and the causal relationships between the PPP and its impacts were investigated. This work showed that collaboration between the public and private sector occurred at several administrative levels. The actors considered a variety of impacts, on the economy, business, trust, and health, which were then measured through different indicators. The actors also identified the added value of the PPP to enrich those impacts. The participatory impact pathway methodology helped to strengthen the engagement of actors in the PPP and to formulate recommendations at the policy level to favor positive results. This case study represents a milestone in building a participatory evaluation framework of PPP in the veterinary domain.

18.
J Fungi (Basel) ; 8(4)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35448585

RESUMO

Cellular recycling via autophagy-associated proteins is a key catabolic pathway critical to invasive fungal pathogen growth and virulence in the nutrient-limited host environment. Protein kinase A (PKA) is vital for the growth and virulence of numerous fungal pathogens. However, the underlying basis for its regulation of pathogenesis remains poorly understood in any species. Our Aspergillus fumigatus PKA-dependent whole proteome and phosphoproteome studies employing advanced mass spectroscopic approaches identified numerous previously undefined PKA-regulated proteins in catabolic pathways. Here, we demonstrate reciprocal inhibition of autophagy and PKA activity, and identify 16 autophagy-associated proteins as likely novel PKA-regulated effectors. We characterize the novel PKA-phosphoregulated sorting nexin Atg20, and demonstrate its importance for growth, cell wall stress response, and virulence of A. fumigatus in a murine infection model. Additionally, we identify physical and functional interaction of Atg20 with previously characterized sorting nexin Atg24. Furthermore, we demonstrate the importance of additional uncharacterized PKA-regulated putative autophagy-associated proteins to hyphal growth. Our data presented here indicate that PKA regulates the autophagy pathway much more extensively than previously known, including targeting of novel effector proteins with fungal-specific functions important for invasive disease.

19.
Eukaryot Cell ; 9(3): 472-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20097742

RESUMO

The Aspergillus fumigatus DeltapmrA (Golgi apparatus Ca(2+)/Mn(2+) P-type ATPase) strain has osmotically suppressible basal growth defects and cationic tolerance associated with increased expression of calcineurin pathway genes. Despite increased beta-glucan and chitin content, it is hypersensitive to cell wall inhibitors but remains virulent, suggesting a role for PmrA in cation homeostasis and cell wall integrity.


Assuntos
Aspergillus fumigatus/metabolismo , Aspergillus fumigatus/patogenicidade , ATPases Transportadoras de Cálcio/genética , ATPases Transportadoras de Cálcio/metabolismo , Cátions/metabolismo , Parede Celular/metabolismo , Complexo de Golgi/enzimologia , Homeostase , Aminoglicosídeos/farmacologia , Animais , Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Caspofungina , Cátions/farmacologia , Proliferação de Células/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Quitina/metabolismo , Farmacorresistência Fúngica/genética , Equinocandinas/farmacologia , Ácido Egtázico/farmacologia , Proteínas Fúngicas/genética , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Homeostase/genética , Concentração de Íons de Hidrogênio , Aspergilose Pulmonar Invasiva/genética , Aspergilose Pulmonar Invasiva/patologia , Estimativa de Kaplan-Meier , Lipopeptídeos , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Solução Salina Hipertônica/farmacologia , Sorbitol/farmacologia , Estresse Fisiológico/genética , Regulação para Cima/genética , beta-Glucanas/metabolismo
20.
Poult Sci ; 100(6): 101023, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33872862

RESUMO

Currently, there is a need for more and better poultry health services in Ethiopia. However, nationwide data showing the weaknesses of poultry health services are scanty. Hence, availability of diagnostic, vaccination, and clinical services for poultry was assessed. Focus group discussions and household questionnaire survey were conducted with poultry keepers in 10 districts. Lack of poultry health experts, clinical services, drugs, vaccination, and knowledge and skills were identified as top five key findings. In total, 31.6% of respondents reported availability of poultry diagnosis service. Having flock size of 11-20 chickens had higher probabilities of accessing better diagnosis service (AOR = 2.77; 95% CI: 1.12-3.64). Access to diagnosis was directly linked with the availability of veterinary clinics in their localities (AOR = 2.65; 95% CI: 1.16-6.63). Moreover, low access to treatment services (22.98%) was reported and traditional remedies with priority index of 0.68 were reported to be the most commonly used. Chicken flocks with a history of disease occurrence were more likely to have a decision to go for modern treatment services (AOR = 4.26; 95% CI: 2.28-7.95). Only 35.7% of chicken keepers had their flocks vaccinated, and this was irregularly and randomly given, mainly against Newcastle disease. Only 52.9% of them were vaccinated by trained animal health experts. Chicken flocks with availability of veterinary clinics within 5 km were more likely (AOR = 1.62; 95% CI: 1.03-2.54) to have access to vaccination services. Only 53.0% of the chicken flocks had availability of clinics and chicken flocks in Tigray (AOR = 2.15; 95% CI: 1.03- 4.52) and Oromia (AOR = 5.74; 95%CI: 2.51-13.10) had better availability of clinics. Chicken flocks found in Bako district were less likely (AOR = 0.41; 95% CI: 0.18-0.92). The low availability of diagnostic, vaccination, and clinical services shows that poultry health services in Ethiopia have not received attention despite its top national agenda. Hence, the existing low poultry health services need to be solved through public-private partnership, producing adequate poultry health experts, availing vaccines, diagnostics, and therapeutics in the local markets.


Assuntos
Galinhas , Aves Domésticas , Animais , Estudos Transversais , Etiópia , Serviços de Saúde , Vacinação/veterinária
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