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1.
J Infect Dis ; 223(1): 166-173, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-32658292

RESUMO

Murine infections with most Coccidioides spp. strains are lethal by 3 weeks, limiting the study of immune responses. Coccidioides posadasii, strain 1038 (Cp1038), while slowly lethal, resulted in protracted survival of C57BL/6 (B6) mice. In resistant (B6D2)F1/J mice, lung fungal burdens stabilized by week 4 without progression through week 16, better modeling human coccidioidal infections after their immunologic control. Immunodeficient tumor necrosis factor (Tnf) α knockout (KO) and interferon (Ifn) γ receptor 1 (Ifn-γr1) KO mice survived a median of 22.5 and 34 days, compared with 70 days in B6 mice (P = .001 and P < .01, respectively), though 14-day lung fungal burden studies showed little difference between Ifn-γr1 KO and B6 mice. B6 mice showed peak concentrations of key inflammatory lung cytokines, including interleukin 6, 23, and 17A, Tnf-α, and Ifn-γ, only after 4 weeks of infection. The slower progression in B6 and the acquired fungal burden stability in B6D2 mice after Cp1038 infection greatly increases the array of possible immunologic studies.


Assuntos
Coccidioides/imunologia , Coccidioidomicose/imunologia , Modelos Animais de Doenças , Animais , Coccidioidomicose/microbiologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
2.
Artigo em Inglês | MEDLINE | ID: mdl-29437615

RESUMO

Coccidioidal meningitis can cause significant morbidity, and lifelong antifungal therapy is often required. VT-1598 is a fungus-specific Cyp51 inhibitor that has potent in vitro activity against Coccidioides species. We evaluated the in vivo efficacy of VT-1598 in murine models of central nervous system coccidioidomycosis caused by C. posadasii and C. immitis Infection was introduced via intracranial inoculation, and therapy began 48 h postinoculation. Oral treatments consisted of vehicle control, VT-1598, and positive controls of fluconazole in the C. immitis study and VT-1161 in the C. posadasii study. Treatment continued for 7 and 14 days in the fungal-burden and survival studies, respectively. Fungal burden was assessed in brain tissue collected 24 to 48 h posttreatment in the fungal-burden studies, on the days the mice succumbed to infection, or at prespecified endpoints in the survival studies. VT-1598 plasma concentrations were also measured in the C. posadasii study. VT-1598 resulted in significant improvements in survival in mice infected with either species. In addition, the fungal burden was significantly reduced in the fungal-burden studies. Plasma concentrations 48 h after dosing stopped remained above the VT-1598 MIC against the C. posadasii isolate, although levels were undetectable in the survival study after a 4-week washout. Whereas fungal burden remained suppressed after a 2-week washout in the C. immitis model, a higher fungal burden was observed in the survival arm of the C. posadasii model. This in vivo efficacy supports human studies to establish the utility of VT-1598 for the treatment of coccidioidomycosis.


Assuntos
Inibidores de 14-alfa Desmetilase/uso terapêutico , Coccidioides/efeitos dos fármacos , Coccidioides/patogenicidade , Coccidioidomicose/tratamento farmacológico , Animais , Fluconazol/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Modelos Teóricos
3.
Artigo em Inglês | MEDLINE | ID: mdl-28289027

RESUMO

Coccidioidomycosis can be a chronic, systemic fungal infection requiring long-term to lifetime medication. Thus, there is a need for improved antifungal agents with greater efficacy and reduced toxicity. VT-1161 has a low affinity for mammalian cytochromes and potently inhibits fungal CYP51 with proven efficacy in murine models of central nervous system (CNS) and respiratory coccidioidomycosis. Dogs experience coccidioidomycosis similar to humans and are a useful preclinical model for naturally occurring disease. Twenty-four client-owned dogs diagnosed with respiratory coccidioidomycosis based on radiography, serology, clinical signs, and clinicopathologic abnormalities were treated with a loading dose of VT-1161 for 14 days, followed by 46 days of a lower maintenance dose. Twelve dogs received a high dose (29 mg/kg loading, 6 mg/kg maintenance) and 12 received a low dose (10 mg/kg loading, 1.6 mg/kg maintenance). Response to treatment was assessed by calculating the reduction in disease scores at exit compared to disease scores at enrollment. Overall, 20 of 24 (83%) dogs had ≥50% reduction in enrollment disease scores at exit (P < 0.001), with no difference between the high- and low-dose groups (P = 0.66). Time-weighted average plasma concentrations for the high- and low-dose groups were 39 ± 5 µg/ml and 19 ± 2 µg/ml, respectively. In this open-label study, VT-1161 was efficacious for the treatment of respiratory coccidioidomycosis in naturally infected dogs. Combined with previously reported murine data, this finding supports the further development of VT-1161 for the treatment of coccidioidomycosis in humans.


Assuntos
Inibidores de 14-alfa Desmetilase/uso terapêutico , Antifúngicos/uso terapêutico , Coccidioides/efeitos dos fármacos , Coccidioidomicose/tratamento farmacológico , Coccidioidomicose/veterinária , Doenças do Cão/tratamento farmacológico , Piridinas/uso terapêutico , Tetrazóis/uso terapêutico , Animais , Antifúngicos/farmacocinética , Coccidioidomicose/microbiologia , Modelos Animais de Doenças , Doenças do Cão/microbiologia , Cães , Feminino , Masculino , Piridinas/farmacocinética , Esterol 14-Desmetilase/metabolismo , Tetrazóis/farmacocinética
4.
Infect Immun ; 84(10): 3007-16, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27481239

RESUMO

The CPS1 gene was identified as a virulence factor in the maize pathogen Cochliobolus heterostrophus Hypothesizing that the homologous gene in Coccidioides posadasii could be important for virulence, we created a Δcps1 deletion mutant which was unable to cause disease in three strains of mice (C57BL/6, BALB/c, or the severely immunodeficient NOD-scid,γc(null) [NSG]). Only a single colony was recovered from 1 of 60 C57BL/6 mice following intranasal infections of up to 4,400 spores. Following administration of very high doses (10,000 to 2.5 × 10(7) spores) to NSG and BALB/c mice, spherules were observed in lung sections at time points from day 3 to day 10 postinfection, but nearly all appeared degraded with infrequent endosporulation. Although the role of CPS1 in virulence is not understood, phenotypic alterations and transcription differences of at least 33 genes in the Δcps1 strain versus C. posadasii is consistent with both metabolic and regulatory functions for the gene. The in vitro phenotype of the Δcps1 strain showed slower growth of mycelia with delayed and lower spore production than C. posadasii, and in vitro spherules were smaller. Vaccination of C57BL/6 or BALB/c mice with live Δcps1 spores either intranasally, intraperitoneally, or subcutaneously resulted in over 95% survival with mean residual lung fungal burdens of <1,000 CFU from an otherwise lethal C. posadasii intranasal infection. Considering its apparently complete attenuation of virulence and the high degree of resistance to C. posadasii infection when used as a vaccine, the Δcps1 strain is a promising vaccine candidate for preventing coccidioidomycosis in humans or other animals.


Assuntos
Coccidioides/fisiologia , Coccidioidomicose/genética , Deleção de Sequência , Fatores de Virulência/genética , Virulência/fisiologia , Animais , Coccidioides/genética , Coccidioidomicose/prevenção & controle , Modelos Animais de Doenças , Feminino , Proteínas Fúngicas/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Vacinação/métodos
5.
Antimicrob Agents Chemother ; 59(12): 7249-54, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26369964

RESUMO

Coccidioidomycosis, or valley fever, is a growing health concern endemic to the southwestern United States. Safer, more effective, and more easily administered drugs are needed especially for severe, chronic, or unresponsive infections. The novel fungal CYP51 inhibitor VT-1161 demonstrated in vitro antifungal activity, with MIC50 and MIC90 values of 1 and 2 µg/ml, respectively, against 52 Coccidioides clinical isolates. In the initial animal study, oral doses of 10 and 50 mg/kg VT-1161 significantly reduced fungal burdens and increased survival time in a lethal respiratory model in comparison with treatment with a placebo (P < 0.001). Oral doses of 25 and 50 mg/kg VT-1161 were similarly efficacious in the murine central nervous system (CNS) model compared to placebo treatment (P < 0.001). All comparisons with the positive-control drug, fluconazole at 50 mg/kg per day, demonstrated either statistical equivalence or superiority of VT-1161. VT-1161 treatment also prevented dissemination of infection from the original inoculation site to a greater extent than fluconazole. Many of these in vivo results can be explained by the long half-life of VT-1161 leading to sustained high plasma levels. Thus, the efficacy and pharmacokinetics of VT-1161 are attractive characteristics for long-term treatment of this serious fungal infection.


Assuntos
Inibidores de 14-alfa Desmetilase/farmacologia , Antifúngicos/farmacologia , Coccidioides/efeitos dos fármacos , Coccidioidomicose/tratamento farmacológico , Fluconazol/farmacologia , Fungemia/prevenção & controle , Piridinas/farmacologia , Tetrazóis/farmacologia , Inibidores de 14-alfa Desmetilase/sangue , Inibidores de 14-alfa Desmetilase/farmacocinética , Animais , Antifúngicos/sangue , Antifúngicos/farmacocinética , Coccidioides/enzimologia , Coccidioides/crescimento & desenvolvimento , Coccidioidomicose/microbiologia , Coccidioidomicose/mortalidade , Coccidioidomicose/patologia , Modelos Animais de Doenças , Feminino , Fluconazol/sangue , Fluconazol/farmacocinética , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungemia/microbiologia , Fungemia/mortalidade , Fungemia/patologia , Meia-Vida , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Piridinas/sangue , Piridinas/farmacocinética , Esterol 14-Desmetilase/genética , Esterol 14-Desmetilase/metabolismo , Análise de Sobrevida , Tetrazóis/sangue , Tetrazóis/farmacocinética , Resultado do Tratamento
6.
J Infect Dis ; 209(12): 1949-54, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24421256

RESUMO

Nikkomycin Z (NikZ) is a chitin synthase inhibitor with activity against Coccidioides species that is being developed as a first-in-class orphan product for treatment of coccidioidomycosis. It has previously been shown to reduce lethal respiratory infections in mice to undetectable levels when treatment is begun 48 hours after infection. The studies described here focus on bracketing NikZ doses for phase 2 and 3 clinical trials, using an established mouse respiratory infection as a model and starting treatment 120 hours after infection. A dose of 80 mg/kg/day, divided into 2 doses, nearly eradicated infection, and larger doses did not improve fungal clearance. Increasing the duration of treatment from 1 week to 3 weeks resulted in a greater percentage of culture-negative mice. Comparative data show that plasma levels of NikZ that nearly eradicate Coccidioides in mice are achievable in patients and provide a plausibly effective dose range for initial phase 2 clinical studies.


Assuntos
Aminoglicosídeos/administração & dosagem , Aminoglicosídeos/farmacocinética , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Coccidioidomicose/tratamento farmacológico , Aminoglicosídeos/sangue , Animais , Antifúngicos/sangue , Modelos Animais de Doenças , Cães , Relação Dose-Resposta a Droga , Feminino , Humanos , Camundongos , Dinâmica não Linear
7.
Methods Mol Biol ; 2667: 139-158, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37145282

RESUMO

Coccidioidomycosis, caused by the dimorphic pathogens Coccidioides posadasii and C. immitis, is a fungal disease endemic to the southwestern United States, Mexico, and some regions of Central and South America. The mouse is the primary model for studying pathology and immunology of disease. Mice in general are extremely susceptible to Coccidioides spp., which creates challenges in studying the adaptive immune responses that are required for host control of coccidioidomycosis. Here, we describe how to infect mice to model asymptomatic infection with controlled, chronic granulomas and a slowly progressive but ultimately fatal infection that has kinetics more similar to the human disease.


Assuntos
Coccidioidomicose , Humanos , Animais , Camundongos , Coccidioides , América do Sul/epidemiologia , México
8.
Int J Surg Case Rep ; 94: 107071, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35452942

RESUMO

OBJECTIVE: BTO is the procedure performed to assess the collateral circulation within the Willis circle in a giant ICA aneurysm. An ICA occlusion after BTO is very rare. We present a case of an internal carotid artery occlusion as a complication of BTO that required urgent revascularization surgery. CASE PRESENTATION: A 56-year-old female with a history of transient ischemic attacks for one year was diagnosed with multiple aneurysms: a giant aneurysm of the left supra-clinoid ICA, two small ones on left MCA and right ophthalmic. A BTO was performed to assess collateral supply and determine whether bypass surgery should be necessary. During the procedure, the balloon was detached while insufflating, and the patient had a subsequent neurological decline consistent with an MCA syndrome. EC-IC bypass surgery was performed with an end-to-side anastomosis of STA-MCA by trapping the giant aneurysm and clipping the ipsilateral MCA aneurysm. The patient had a reversal of neurological symptoms and made an uneventful recovery. DISCUSSION: We discuss the epidemiology of giant ICA aneurysms, the indications for BTO, and its complication. Emergency intracranial and extracranial bypass surgery in case of acute ICA injury is also discussed. We also highlighted the attributable factors to treatment strategies under restrictive conditions in Vietnam. CONCLUSIONS: ICA occlusion due to insufflated balloon detachment is an unreported complication in literature. Emergency bypass surgery is a potential treatment choice for this unusual iatrogenic complication.

9.
J Fungi (Basel) ; 8(10)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36294555

RESUMO

The majority of human coccidioidomycosis infections are asymptomatic or self-limited but may have sequestered spherules in highly structured granulomas. Under immunosuppression, reactivation of fungal growth can result in severe disease. B6D2F1 mice asymptomatically infected with C. posadasii strain 1038 were immunosuppressed with dexamethasone (DXM) in drinking water. Treated mice died 16−25 days later, while untreated mice survived (p < 0.001). Flow cytometry of lung granulomas on days 5, 10, 15, and 20 of DXM treatment showed immune cell populations decreased 0.5−1 log compared with untreated mice though neutrophils and CD19+IgD−IgM− cells rebounded by day 20. Histopathology demonstrated loss of granuloma structure by day 5 and increasing spherules through day 20. On day 20, T-cells were nearly absent and disorganized pyogranulomatous lesions included sheets of plasma cells and innumerable spherules. Mice given DXM for 14 days then stopped (DXM stop) survived 6 weeks (9/10). Lung fungal burdens were significantly lower (p = 0.0447) than mice that continued treatment (DXM cont) but higher than untreated mice. Histopathologically, DXM stop mice did not redevelop controlled granulomas by sacrifice, though T-cells were densely scattered throughout the lesions. This demonstrates a mouse model suitable for further study to understand the immunologic components responsible for maintenance control of coccidioidomycosis.

10.
Immunohorizons ; 6(2): 130-143, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35149520

RESUMO

STAT4 plays a critical role in the generation of both innate and adaptive immune responses. In the absence of STAT4, Th1 responses, critical for resistance to fungal disease, do not occur. Infection with the dimorphic fungus, Coccidioides, is a major cause of community-acquired pneumonia in the endemic regions of Arizona and California. In some people and often for unknown reasons, coccidioidal infection results in hematogenous dissemination and progressive disease rather than the typical self-limited pneumonia. Members of three generations in a family developed disseminated coccidioidomycosis, prompting genetic investigation. All affected family members had a single heterozygous base change in STAT4, c.1877A>G, causing substitution of glycine for glutamate at AA626 (STAT4E626G/+ ). A knockin mouse, heterozygous for the substitution, developed more severe experimental coccidioidomycosis than did wild-type mice. Stat4E626G/+ T cells were deficient in production of IFN-γ after anti-CD3/CD28 stimulation. Spleen cells from Stat4E626G mice showed defective responses to IL-12/IL-18 stimulation in vitro. In vivo, early postinfection, mutant Stat4E626G/+ mice failed to produce IFN-γ and related cytokines in the lung and to accumulate activated adaptive immune cells in mediastinal lymph nodes. Therefore, defective early induction of IFN-γ and adaptive responses by STAT4 prevents normal control of coccidioidomycosis in both mice and humans.


Assuntos
Coccidioidomicose , Fator de Transcrição STAT4 , Animais , Coccidioidomicose/genética , Predisposição Genética para Doença , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Mutação Puntual , Fator de Transcrição STAT4/genética
11.
Planta Med ; 77(18): 1996-2002, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21830186

RESUMO

To investigate the inhibitory effects of Artemisia princeps Pamp. (family Asteraceae) essential oil (APEO) and its main constituents against bacterial vaginosis and vulvovaginal candidiasis, their antimicrobial activities against Gardnerella vaginalis and Candida albicans in vitro and their anti-inflammatory effects against G. vaginalis-induced vaginosis and vulvovaginal candidiasis were examined in mice. APEO and its constituents eucalyptol and α-terpineol were found to inhibit microbe growths. α-Terpineol most potently inhibited the growths of G. vaginalis and C. albicans with MIC values of 0.06 and 0.125 % (v/v), respectively. The antimicrobial activity of α-terpineol was found to be comparable to that of clotrimazole. Intravaginal treatment with APEO, eucalyptol, or α-terpineol significantly decreased viable G. vaginalis and C. albicans numbers in the vaginal cavity and myeloperoxidase activity in mouse vaginal tissues compared with controls. These agents also inhibited the expressions of proinflammatory cytokines (IL-1 ß, IL-6, TNF- α), COX-2, iNOS, and the activation of NF- κB and increased expression of the anti-inflammatory cytokine IL-10. In addition, they inhibited the expressions of proinflammatory cytokines and the activation of NF- κB in lipopolysaccharide-stimulated peritoneal macrophages, and α-terpineol most potently inhibited the expressions of proinflammatory cytokines and NF- κB activation. Based on these findings, APEO and its constituents, particularly α-terpineol, ameliorate bacterial vaginosis and vulvovaginal candidiasis by inhibiting the growths of vaginal pathogens and the activation of NF- κB.


Assuntos
Artemisia/química , Candidíase Vulvovaginal/tratamento farmacológico , Cicloexanóis/farmacologia , Cicloexenos/farmacologia , Monoterpenos/farmacologia , NF-kappa B/metabolismo , Fitoterapia , Vaginose Bacteriana/tratamento farmacológico , Animais , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Candidíase Vulvovaginal/microbiologia , Clotrimazol/farmacologia , Monoterpenos Cicloexânicos , Cicloexanóis/administração & dosagem , Cicloexenos/administração & dosagem , Citocinas/química , Eucaliptol , Feminino , Gardnerella vaginalis/efeitos dos fármacos , Gardnerella vaginalis/patogenicidade , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Monoterpenos/administração & dosagem , Óleos Voláteis/administração & dosagem , Óleos Voláteis/farmacologia , Peroxidase/química , Vaginose Bacteriana/microbiologia
12.
Immunopharmacol Immunotoxicol ; 33(3): 539-44, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21275795

RESUMO

To isolate antipruritic lactic acid bacteria (LAB) from kimchi, a traditional Korean food, we investigated the interleukin (IL)-4 production-inhibitory effect in the colon of mice for previously isolated LAB. Orally administered Lactobacillus plantarum PM008 potently inhibited the expression of IgE-switching cytokine, IL-4, and of proinflammatory cytokines, IL-1ß and TNF-α, in the colon of mice. Its inhibitory effect was dependent on the dosage and administration period. When PM008 was orally administered to mice, the number of PM008 detected in the intestine and feces by polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH) methods was dependent on the administration dosage and period. The number of PM008 attached in the intestine was gradually decreased with increasing time after completion of its oral administration. PM008 dose-dependently inhibited the scratching behavior induced by histamine or compound 48/80. PM008 treated at a dose of 1 × 10(10) CFU for 14 days inhibited the histamine- and compound 48/80-induced scratching behaviors by 32.8% and 48.6%, respectively. This inhibitory effect continued, although reduced, at 7 days after stopping the oral administration of PM008 attached in the intestine. Based on these findings, L. plantarum PM008 may improve pruritus by inhibiting IL-4 expression.


Assuntos
Antipruriginosos/farmacologia , Lactobacillus plantarum , Probióticos/farmacologia , Prurido/tratamento farmacológico , Animais , Colo/imunologia , Colo/metabolismo , Colo/microbiologia , Fezes/microbiologia , Histamina/farmacologia , Interleucina-1beta/antagonistas & inibidores , Interleucina-4/antagonistas & inibidores , Interleucina-4/biossíntese , Lactobacillus plantarum/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Probióticos/isolamento & purificação , Prurido/induzido quimicamente , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese , p-Metoxi-N-metilfenetilamina/farmacologia
13.
Front Cell Infect Microbiol ; 11: 796114, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35174101

RESUMO

Tumor necrosis factor alpha (TNFα) is a pluripotent cytokine that is important in many infections, though its role in Coccidioides infection remains poorly understood. The need to understand TNFα in Coccidioides infection has increased recently with the widespread use of TNFα inhibitors for a wide variety of autoimmune conditions. Here, we couple the newly developed Coccidioides infection model using strain Cp1038 and C57BL/6 × DBA/2J F1 (B6D2F1) mice. B6D2F1 mice develop long-lasting control of Cp1038. Treatment of B6D2F1 mice with anti-TNFα antibodies permits significant fungal proliferation and death. Additionally, we show that antibody treatment limited to the first 2 weeks of infection was sufficient to induce this same loss of fungal control. Importantly, anti-TNFα antibody treatment initiated after fungal control leads to a loss of host control. These results highlight the importance of TNFα in both the initial control of murine Coccidioides and ongoing suppression of the fungal disease.


Assuntos
Coccidioidomicose , Inibidores do Fator de Necrose Tumoral/farmacologia , Animais , Coccidioides , Coccidioidomicose/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Fator de Necrose Tumoral alfa/antagonistas & inibidores
14.
Front Cell Infect Microbiol ; 11: 790488, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071044

RESUMO

Disseminated coccidioidomycosis (DCM), often a severe and refractory disease leading to poor outcomes, is a risk for people with certain primary immunodeficiencies (PID). Several DCM-associated PID (STAT4, STAT3, IFNγ, and Dectin-1) are modeled in mice. To determine if vaccination could provide these mice protection, mice with mutations in Stat4, Stat3, Ifngr1, Clec7a (Dectin-1), and Rag-1 (T- and B-cell deficient) knockout (KO) mice were vaccinated with the live, avirulent, Δcps1 vaccine strain and subsequently challenged intranasally with pathogenic Coccidioides posadasii Silveira strain. Two weeks post-infection, vaccinated mice of all strains except Rag-1 KO had significantly reduced lung and spleen fungal burdens (p<0.05) compared to unvaccinated control mice. Splenic dissemination was prevented in most vaccinated immunodeficient mice while all unvaccinated B6 mice and the Rag-1 KO mice displayed disseminated disease. The mitigation of DCM by Δcps1 vaccination in these mice suggests that it could also benefit humans with immunogenetic risks of severe disease.


Assuntos
Coccidioidomicose , Vacinas Fúngicas , Animais , Coccidioidomicose/prevenção & controle , Pulmão , Camundongos , Camundongos Endogâmicos C57BL , Vacinas Atenuadas
15.
Vaccine ; 39(47): 6894-6901, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34696935

RESUMO

Coccidioidomycosis is a significant health problem of dogs and humans in endemic regions, especially California and Arizona in the U.S. Both species would greatly benefit from a vaccine to prevent this disease. A live avirulent vaccine candidate, Δcps1, was tested for tolerability and efficacy to prevent pulmonary coccidioidomycosis in a canine challenge model. Vaccine injection-site reactions were transient and there were no systemic effects observed. Six of seven vaccine sites tested and all draining lymph nodes were sterile post-vaccination. Following infection with Coccidioides posadasii, strain Silveira, arthroconidia into the lungs, dogs given primary and booster vaccinations had significantly reduced lung fungal burdens (P = 0.0003) and composite disease scores (P = 0.0002) compared to unvaccinated dogs. Dogs vaccinated once had fungal burdens intermediate between those given two doses or none, but disease scores were not significantly different from unvaccinated (P = 0.675). Δcps1 was well-tolerated in the dogs and it afforded a high level of protection when given as prime and boost. These results drive the Δcps1 vaccine toward a licensed veterinary vaccine and support continued development of this vaccine to prevent coccidioidomycosis in humans.


Assuntos
Coccidioidomicose , Vacinas Fúngicas , Animais , Coccidioidomicose/prevenção & controle , Coccidioidomicose/veterinária , Cães , Pulmão , Esporos Fúngicos , Vacinação , Vacinas Atenuadas
16.
Acta Pharmacol Sin ; 31(6): 718-24, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20453872

RESUMO

AIM: To explore whether intestinal microflora plays a role in anti-pruritic activity of baicalin, a main constituent of the rhizome of Scutellaria baicalensis (SB). METHODS: Baicalin was anaerobically incubated with human fecal microflora, and its metabolites, baicalein and oroxylin A, were isolated. The inhibitory effect of baicalin and its metabolites was accessed in histamine- or compound 48/80-induced scratching behavior in mice. RESULTS: Baicalin was metabolized to baicalein and oroxylin A, with metabolic activities of 40.2+/-26.2 and 1.2+/-1.1 nmol.h(-1).mg(-1) wet weight of human fecal microflora, respectively. Baicalin (20, 50 mg/kg) showed more potent inhibitory effect on histamine-induced scratching behavior when orally administered than intraperitoneally. In contrast, baicalein and oroxylin A had more potent inhibitory effect when the intraperitoneally administered. The anti-scratching behavior activity of oral baicalin and its metabolites was in proportion to their inhibition on histamine-induced increase of vascular permeability with oroxylin A more potent than baicalein and baicalin. In Magnus test using guinea pig ileum, oroxylin A is more potent than baicalein and baicalin in inhibition of histamine-induced contraction. The anti-scratching behavioral effect of oral baicalin was significantly reduced when oral antibiotics were simultaneously administered, whereas the effect of baicalein and oroxylin A were not affected. CONCLUSION: Oral baicalin may be metabolized by intestinal microflora into baicalein and oroxylin A, which ameliorate pruritic reactions through anti-histamine action.


Assuntos
Antipruriginosos/uso terapêutico , Flavanonas/uso terapêutico , Flavonoides/uso terapêutico , Antagonistas dos Receptores Histamínicos/uso terapêutico , Prurido/tratamento farmacológico , Animais , Antibacterianos/administração & dosagem , Antipruriginosos/análise , Antipruriginosos/metabolismo , Fezes/microbiologia , Flavanonas/análise , Flavonoides/análise , Flavonoides/metabolismo , Cobaias , Histamina/administração & dosagem , Antagonistas dos Receptores Histamínicos/análise , Antagonistas dos Receptores Histamínicos/metabolismo , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Fitoterapia , Scutellaria baicalensis/química , Scutellaria baicalensis/metabolismo , Estreptomicina/administração & dosagem , Tetraciclina/administração & dosagem
17.
Immunopharmacol Immunotoxicol ; 32(3): 357-63, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20095799

RESUMO

To investigate the antiallergic effect of the rhizome of Anemarrhena asphodeloides (AA, family Liliaceae), which was found to inhibit the mouse passive cutaneous anaphylaxis (PCA) reaction induced by the antigen-immunoglobulin E (IgE) complex in preliminary experiments, main steroidal saponins, timosaponins AIII, BIII, and D, were isolated and their inhibitory effects against PCA reaction and scratching behaviors investigated in mice. Oral administration of three main steroidal sapogenins blocked the PCA reaction and scratching behaviors, timosaponin AIII was the most potent. However, intraperitoneal administration of timosaponin AIII showed weak inhibition. To understand its metabolism and antiallergic mechanism, timosaponin AIII was anaerobically incubated with human intestinal microflora to afford a main metabolite, sarsasapogenin. Intraperitoneal administration of sarsasapogenin inhibited allergic reaction more potently than timosaponin AIII. In addition, sarsasapogenin more potently inhibited degranulation and IL-4 protein expression of RBL-2H3 cells induced by IgE-antigen complex than timosaponin AIII. On the basis of these findings, antiallergic effect of AA may be due to those of its steroidal constituents, and that of timosaponin AIII may be activated by using intestinal microflora.


Assuntos
Anemarrhena/química , Antialérgicos/administração & dosagem , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Prurido/tratamento farmacológico , Rizoma/química , Saponinas/administração & dosagem , Saponinas/uso terapêutico , Esteroides/uso terapêutico , Anemarrhena/imunologia , Animais , Antialérgicos/química , Antialérgicos/isolamento & purificação , Complexo Antígeno-Anticorpo/efeitos dos fármacos , Células Cultivadas , Humanos , Imunoglobulina E/análise , Interleucina-4/análise , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Ratos , Ratos Sprague-Dawley , Rizoma/imunologia , Saponinas/química , Saponinas/isolamento & purificação , Espirostanos/administração & dosagem , Espirostanos/análise , Espirostanos/metabolismo , Esteroides/química , Esteroides/isolamento & purificação , Fator de Necrose Tumoral alfa/análise
18.
Anaerobe ; 16(3): 289-92, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20193771

RESUMO

Clostridium perfringens type A is the most common cause of poultry necrotic enteritis (NE). Of the four "major" toxins, type A strains produce only alpha toxin (CPA), which has long been considered a major factor in pathogenesis of NE. We investigated the virulence for poultry of type A strains from a variety of enteric sources. Newly-hatched CornishxRock chicks were fed a low protein diet for one week, a high protein diet for a second week, and then challenged with log-phase cultures of C. perfringens, mixed 3:4 (v/v) with high protein feed. Strain JGS4143 [genotype A, beta2 positive (cpb2(pos)), from a field case of NE] produced gross lesions compatible with NE in >85% of challenged birds. However, strains JGS1714 (enterotoxigenic genotype A, cpb2(pos), human food poisoning), JGS1936 (genotype A, cpb2(neg), bovine neonatal enteritis), JGS4142 (genotype A, cpb2(pos), bovine jejunal hemorrhage syndrome), JGS1473 (genotype A, cpb2(pos), chicken normal flora), JGS1070 (genotype C, cpb2(pos), porcine hemorrhagic enteritis), JGS1882 (genotype A, cpb2(pos), porcine neonatal enteritis), JGS1120 (ATCC 13124, genotype A, cpb2(neg), gas gangrene), JGS4151 (strain 13, genotype A, cpb2(pos), canine), and JGS4303 (SM101, enterotoxigenic genotype A, cpb2(neg), human food poisoning) failed to produce disease. In vivo passage failed to increase virulence of the non-NE strains. NE strains must have specific poultry-associated virulence attributes, such as the recently identified NetB and other factors, which allow for the development of disease.


Assuntos
Toxinas Bacterianas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Infecções por Clostridium/veterinária , Clostridium perfringens/patogenicidade , Enterite/veterinária , Doenças das Aves Domésticas/microbiologia , Fosfolipases Tipo C/metabolismo , Animais , Bovinos , Galinhas , Infecções por Clostridium/microbiologia , Clostridium perfringens/isolamento & purificação , Enterite/microbiologia , Humanos , Aves Domésticas , Especificidade da Espécie , Suínos , Virulência
19.
Anaerobe ; 16(6): 614-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20934524

RESUMO

Poultry necrotic enteritis (NE) is caused by specific strains of Clostridium perfringens, most of which are type A. The role of alpha toxin (CPA) in NE has been called into question by the finding that an engineered cpa mutant retains full virulence in vivo[9]. This is in contrast to the finding that immunization with CPA toxoids protects against NE. We confirmed the earlier findings, in that 14-day-old Cornish × Rock broiler chicks challenged with a cpa mutant developed lesions compatible with NE in >90% of birds inoculated with the mutant. However, CPA was detected in amounts ranging from 10 to >100 ng per g of gut contents and mucosa in birds inoculated with the cpa mutant, the wildtype strain from which the mutant was constructed, and our positive control strain. There was a direct relationship between lesion severity and amount of CPA detected (R = 0.89-0.99). These findings suggest that the role of CPA in pathogenesis of NE requires further investigation.


Assuntos
Toxinas Bacterianas/toxicidade , Proteínas de Ligação ao Cálcio/toxicidade , Clostridium perfringens/genética , Clostridium perfringens/patogenicidade , Enterite/veterinária , Intestinos/microbiologia , Proteínas Mutantes/toxicidade , Doenças das Aves Domésticas/microbiologia , Fosfolipases Tipo C/toxicidade , Animais , Toxinas Bacterianas/genética , Aves , Proteínas de Ligação ao Cálcio/genética , Galinhas , Enterite/microbiologia , Histocitoquímica , Intestinos/patologia , Proteínas Mutantes/genética , Fosfolipases Tipo C/genética
20.
J Microbiol Biotechnol ; 20(1): 217-23, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20134255

RESUMO

To evaluate the antiallergic effect of fermented Ixeris sonchifolia (IS, family Compositae), we prepared IS Kimchi, isolated Lactic acid bacteria (LAB) from it, fermented IS with these LAB, and investigated their antiallergic effects. IS Kimchi more potently inhibited the passive cutaneous anaphylaxis (PCA) reaction induced by an IgE-antigen complex as well as the scratching behavior induced by compound 48/80 or histamine than IS. When IS was fermented with LAB isolated from IS Kimchi, its antiallergic effects was also increased. Of LAB used for fermentation, Lactobacillus brevis more potently increased the antiallergic effects. Its main constituents, chlorogenic acid and luteolin potently inhibited PCA reaction induced by IgE-antigen complex as well as pruritus induced by compound 48/80 or histamine. These constituents inhibited the expression of proinflammatory and allergic cytokines, TNF-alpha and IL-4, and transcription factor, NF-kappaB, activation induced by IgE-antigen complex in RBL-2H3 cells, as well as the degranulation of RBL-2H3 cells induced by an IgE-antigen complex. Luteolin more potently inhibited these allergic reactions than chlorogenic acid. These findings suggest that antiallergic effect of IS can be increased by LAB fermentation and fermented IS might improve allergic reactions, such as pruritus, anaphylaxis, and inflammation.


Assuntos
Antialérgicos/imunologia , Asteraceae/imunologia , Bactérias/metabolismo , Fermentação , Inflamação/tratamento farmacológico , Extratos Vegetais/imunologia , Animais , Antialérgicos/administração & dosagem , Asteraceae/química , Asteraceae/microbiologia , Bactérias/imunologia , Linhagem Celular , Citocinas/genética , Citocinas/imunologia , Inflamação/genética , Inflamação/imunologia , Levilactobacillus brevis/metabolismo , Leuconostoc/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Extratos Vegetais/administração & dosagem
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