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1.
BMC Cancer ; 21(1): 404, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853560

RESUMO

BACKGROUND AND AIM: Triazole, polyene, and echinocandin antifungal agents are extensively used to treat invasive fungal infections (IFIs); however, the optimal prophylaxis option is not clear. This study aimed to determine the optimal agent against IFIs for patients with hematological malignancies. METHODS: Randomized controlled trials (RCTs) comparing the effectiveness of triazole, polyene, and echinocandin antifungal agents with each other or placebo for IFIs in patients with hematological malignancies were searched. This Bayesian network meta-analysis was performed for all agents. RESULTS: The network meta-analyses showed that all triazoles, amphotericin B, and caspofungin, but not micafungin, reduced IFIs. Posaconazole was superior to fluconazole [odds ratio (OR), 0.30; 95% credible interval (CrI), 0.12-0.60], itraconazole (OR, 0.40; 95% CrI, 0.15-0.85), and amphotericin B (OR, 4.97; 95% CrI, 1.73-11.35). It also reduced all-cause mortality compared with fluconazole (OR, 0.35; 95% CrI, 0.08-0.96) and itraconazole (OR, 0.33; 95% CrI, 0.07-0.94), and reduced the risk of adverse events compared with fluconazole (OR, 0.02; 95% CrI, 0.00-0.03), itraconazole (OR, 0.01; 95% CrI, 0.00-0.02), posaconazole (OR, 0.02; 95% CrI, 0.00-0.03), voriconazole (OR, 0.005; 95% CrI, 0.00 to 0.01), amphotericin B (OR, 0.004; 95% CrI, 0.00-0.01), and caspofungin (OR, 0.05; 95% CrI, 0.00-0.42) despite no significant difference in the need for empirical treatment and the proportion of successful treatment. CONCLUSIONS: Posaconazole might be an optimal prophylaxis agent because it reduced IFIs, all-cause mortality, and adverse events, despite no difference in the need for empirical treatment and the proportion of successful treatment.


Assuntos
Antifúngicos/uso terapêutico , Equinocandinas/uso terapêutico , Neoplasias Hematológicas/complicações , Infecções Fúngicas Invasivas/etiologia , Infecções Fúngicas Invasivas/prevenção & controle , Polienos/uso terapêutico , Triazóis/uso terapêutico , Equinocandinas/administração & dosagem , Humanos , Metanálise em Rede , Polienos/administração & dosagem , Profilaxia Pré-Exposição , Viés de Publicação , Resultado do Tratamento , Triazóis/administração & dosagem
2.
Mycoses ; 64(6): 583-602, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33529414

RESUMO

Approximately 70-75% of women will have vulvovaginal candidosis (VVC) at least once in their lifetime. In premenopausal, pregnant, asymptomatic and healthy women and women with acute VVC, Candida albicans is the predominant species. The diagnosis of VVC should be based on clinical symptoms and microscopic detection of pseudohyphae. Symptoms alone do not allow reliable differentiation of the causes of vaginitis. In recurrent or complicated cases, diagnostics should involve fungal culture with species identification. Serological determination of antibody titres has no role in VVC. Before the induction of therapy, VVC should always be medically confirmed. Acute VVC can be treated with local imidazoles, polyenes or ciclopirox olamine, using vaginal tablets, ovules or creams. Triazoles can also be prescribed orally, together with antifungal creams, for the treatment of the vulva. Commonly available antimycotics are generally well tolerated, and the different regimens show similarly good results. Antiseptics are potentially effective but act against the physiological vaginal flora. Neither a woman with asymptomatic colonisation nor an asymptomatic sexual partner should be treated. Women with chronic recurrent Candida albicans vulvovaginitis should undergo dose-reducing maintenance therapy with oral triazoles. Unnecessary antimycotic therapies should always be avoided, and non-albicans vaginitis should be treated with alternative antifungal agents. In the last 6 weeks of pregnancy, women should receive antifungal treatment to reduce the risk of vertical transmission, oral thrush and diaper dermatitis of the newborn. Local treatment is preferred during pregnancy.


Assuntos
Candidíase Vulvovaginal , Antibacterianos/efeitos adversos , Antifúngicos/uso terapêutico , Candida albicans/efeitos dos fármacos , Candida albicans/isolamento & purificação , Candida glabrata/efeitos dos fármacos , Candida glabrata/isolamento & purificação , Candidíase Vulvovaginal/diagnóstico , Candidíase Vulvovaginal/microbiologia , Candidíase Vulvovaginal/terapia , Causalidade , Ciclopirox/administração & dosagem , Ciclopirox/uso terapêutico , Anticoncepcionais/administração & dosagem , Anticoncepcionais/efeitos adversos , Diabetes Mellitus , Feminino , Hormônios/efeitos adversos , Humanos , Hifas/isolamento & purificação , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Recém-Nascido , Polienos/administração & dosagem , Polienos/uso terapêutico , Gravidez , Vaginite/diagnóstico
3.
Clin Microbiol Infect ; 26(11): 1481-1487, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32535150

RESUMO

BACKGROUND: The goal of therapeutic drug monitoring (TDM) is to determine the appropriate exposure of difficult-to-manage medications to optimize the clinical outcomes in patients in various clinical situations. Concerning antifungal treatment, and knowing that this procedure is expensive and time-consuming, TDM is particularly recommended for certain systemic antifungals: i.e., agents with a well-defined exposure-response relationship and unpredictable pharmacokinetic profile or narrow therapeutic index. Little evidence supports the routine use of TDM for polyenes (amphotericin B), echinocandins, fluconazole or new azoles such as isavuconazole, despite the fact that a better understanding of antifungal exposure may lead to a better response. AIMS: The aim of this work is to review published pharmacokinetic/pharmacodynamic data on systemically administered antifungals, focusing on those for which monitoring is not routinely recommended by experts. SOURCES: A MEDLINE search of the literature in English was performed introducing the following search terms: amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, triazoles, caspofungin, micafungin, anidulafungin, echinocandins, pharmacokinetics, pharmacodynamics, and therapeutic drug monitoring. Review articles and guidelines were also screened. CONTENT: This review collects different pharmacokinetic/pharmacodynamic aspects of systemic antifungals and summarizes recent threshold values for clinical outcomes and adverse events. Although for polyenes, echinocandins, fluconazole and isavuconazole extensive clinical validation is still required for a clear threshold and a routine monitoring recommendation, particular points such as liposome structure or complex pathophysiological conditions affecting final exposure are discussed. For the rest, their better-defined exposure-response/toxicity relationships allow access to useful threshold values and to justify routine monitoring. Additionally, clinical data are needed to better define thresholds that can minimize the development of antifungal resistance. IMPLICATIONS: General TDM for all systemic antifungals is not recommended; however, this approach may help to establish an adequate antifungal exposure for a favourable response, prevention of toxicity or development of resistance in special clinical circumstances.


Assuntos
Antifúngicos/administração & dosagem , Monitoramento de Medicamentos/métodos , Micoses/tratamento farmacológico , Antifúngicos/farmacocinética , Equinocandinas/administração & dosagem , Equinocandinas/farmacocinética , Fluconazol/administração & dosagem , Fluconazol/farmacocinética , Humanos , Nitrilas/administração & dosagem , Nitrilas/farmacocinética , Polienos/administração & dosagem , Polienos/farmacocinética , Guias de Prática Clínica como Assunto , Piridinas/administração & dosagem , Piridinas/farmacocinética , Triazóis/administração & dosagem , Triazóis/farmacocinética
4.
J Ocul Pharmacol Ther ; 35(1): 6-22, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30481082

RESUMO

Polyenes and azoles constitute 2 major drug classes in the antifungal armamentarium used to treat fungal infections of the eye such as fungal keratitis, endophthalmitis, conjunctivitis, and blepharitis. These classes of drugs have come to occupy an important niche in ophthalmic antifungal therapy due to their broad spectrum of activity against a variety of filamentous and yeast-like fungi. Natamycin suspension (Natacyn®), a polyene antifungal drug, is currently the only US FDA-approved formulation for treating ophthalmic fungal infections, whereas the other polyene and azole antifungals such as amphotericin B, fluconazole, itraconazole, ketoconazole, miconazole, voriconazole, and posaconazole are routinely used off-label in the clinical setting. Despite potent antifungal activity, the clinical utility of these agents in ophthalmic infections has been challenged by their physicochemical properties, the unique ocular anatomy and physiology, selective antifungal activity, ocular and systemic toxicity, emergence of resistance and cross-resistance, and absence of reliable techniques for developing a robust in vitro-in vivo correlation. This review discusses the aforementioned challenges and the common approaches undertaken to circumnavigate the difficulties associated with the polyene- and azole-based pharmacotherapy of ophthalmic fungal infections.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Infecções Oculares Fúngicas/tratamento farmacológico , Soluções Oftálmicas/farmacologia , Polienos/farmacologia , Animais , Antifúngicos/administração & dosagem , Azóis/administração & dosagem , Humanos , Testes de Sensibilidade Microbiana , Soluções Oftálmicas/administração & dosagem , Polienos/administração & dosagem
5.
Biomaterials ; 182: 13-20, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30099277

RESUMO

Intra-articular injection of hyaluronic acid (HA) is used to treat osteoarthritis (OA) as a viscosupplement, yet it only provides short-term benefit because HA is cleaved by hyaluronidase and cleared out of the joint after several days. Therefore, we developed a new polymer biolubricant based on poly-oxanorbornane carboxylate to enhance joint lubrication for a prolonged time. Rheological and biotribological studies of the biolubricant reveal viscoelastic properties and coefficient of friction equivalent and superior to that of healthy synovial fluid, respectively. Furthermore, in an ex vivo bovine cartilage plug model, the biolubricant exhibits superior long-term reduction of friction and wear prevention compared to saline and healthy synovial fluid. ISO 10993 biocompatibility tests demonstrate that the biolubricant polymer is non-toxic. In an in vivo rat medial meniscal tear OA model, where the performance of the leading HA viscosupplement (Synvisc-one®) is comparable to the saline control, treatment with the biolubricant affords significant chondroprotection compared to the saline control.


Assuntos
Condrócitos/efeitos dos fármacos , Furanos/administração & dosagem , Articulação do Joelho/efeitos dos fármacos , Menisco/efeitos dos fármacos , Polienos/administração & dosagem , Líquido Sinovial/efeitos dos fármacos , Viscossuplementos/administração & dosagem , Animais , Fenômenos Biomecânicos , Linhagem Celular , Condrócitos/citologia , Condrócitos/metabolismo , Furanos/farmacologia , Furanos/uso terapêutico , Humanos , Injeções Intra-Articulares , Traumatismos do Joelho/tratamento farmacológico , Traumatismos do Joelho/metabolismo , Articulação do Joelho/metabolismo , Masculino , Menisco/lesões , Menisco/metabolismo , Camundongos , Células NIH 3T3 , Osteoartrite/tratamento farmacológico , Polienos/farmacologia , Polienos/uso terapêutico , Ratos Endogâmicos Lew , Líquido Sinovial/metabolismo , Viscossuplementos/farmacologia , Viscossuplementos/uso terapêutico
6.
Oncol Rep ; 37(1): 368-378, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27878284

RESUMO

Manumycin A is a natural antibiotic isolated from Streptomyces parvulus with broad range of biological activities including antineoplastic activity in several in vitro and in vivo cancer models. Immodin [dialyzable leukocyte extract (DLE)] is a dialysate released from disintegrated blood leukocytes of healthy donors which exerts immunonormalizing effects on cell-mediated immune responses. The aim of the present study was to explore the antitumor potential of the combination of manumycin A and Immodin in an experimental breast cancer model. Experiments were carried using a 4T1 tumor-bearing BALB/c mouse model. Survival analysis, tumor growth, hematological and biochemical profiles, leukocyte differential, phagocytic activity of leukocytes and histology of the primary tumor were examined. The combination treatment suppressed the tumor growth and prolonged the survival of tumor-bearing mice, decreased the number of monocytes, plateletes and plateletcrit in peripheral blood of the tumor-bearing mice and increased the infiltration of neutrophils and eosinophils in the primary tumor. Moreover, individual therapies enhanced the phagocytic activity of monocytes and neutrophils. These findings demonstrate the antitumor effect of the combination of manumycin A and Immodin in 4T1 tumor-bearing mice associated with strong antiplatelet activity and innate immunity activation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Leucócitos/química , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Animais , Feminino , Granulócitos/efeitos dos fármacos , Granulócitos/patologia , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/farmacologia , Contagem de Leucócitos , Neoplasias Mamárias Experimentais/mortalidade , Camundongos Endogâmicos BALB C , Fagocitose/efeitos dos fármacos , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/farmacologia , Polienos/administração & dosagem , Alcamidas Poli-Insaturadas/administração & dosagem , Análise de Sobrevida
7.
Nanomedicine ; 12(8): 2395-2404, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27464757

RESUMO

This study was designed to assess the antifungal/anti-biofilm and hemolytic properties of two polyene antibiotics, amphotericin B (AMF) and nystatin (NYS), attached to the surface of magnetic nanoparticles (MNP) against clinical isolates of Candida species and human red blood cells, respectively. The developed nanosystems, MNP@AMF and MNP@NYS, displayed stronger fungicidal activity than unbound AMF or NYS. Synergistic activity was observed with a combination of polyenes and MNPs against all tested Candida strains. Nanosystems were more potent than unbound agents when tested against Candida strains in the presence of pus, and as agents able to prevent Candida biofilm formation. The observed inactivation of catalase Cat1 in Candida cells upon treatment with the nanosystems suggests that disruption of the oxidation-reduction balance is a mechanism leading to inhibition of Candida growth. The significant decrease of polyenes lytic activity against host cells after their attachment to MNPs surface indicates improvement in their biocompatibility.


Assuntos
Anfotericina B/administração & dosagem , Antibacterianos/administração & dosagem , Nanopartículas de Magnetita , Polienos/administração & dosagem , Antifúngicos , Sistemas de Liberação de Medicamentos , Humanos , Testes de Sensibilidade Microbiana
8.
Pest Manag Sci ; 72(7): 1405-10, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26446918

RESUMO

BACKGROUND: The leafminer, Phyllocnistis citrella Stainton, reproduces on leaf flush during winter. Deployment of pheromone during winter could suppress moth populations in spring and summer more than a spring application alone. We tested the primary pheromone component of P. citrella, (Z,Z,E)-7,11,13-hexadecatrienal, released gradually over several months from elastomeric dispensers in a citrus grove in 6.4 ha main plots in winter and/or 3.2 ha subplots in spring (834 mg triene ha(-1) ) and evaluated moth catch and leaf mining. RESULTS: After winter treatment, dispensers provided >85% disruption of male moth catch in traps for 37 weeks, and after spring treatment they provided >92% disruption for 26 weeks, but there was only a 12% reduction in leaf infestation in spring. Two applications were no better than only a single application in spring. Disruption of moth catch was weaker in treated plots where traps were placed high (3.1 m) rather than low (1.6 m) in the tree canopy. CONCLUSION: Dispensers provided effective and persistent disruption of male catch in pheromone-baited monitoring traps but were minimally effective in reducing leaf infestation by P. citrella. Winter application of pheromone did not reduce leaf mining in spring compared with spring application alone. Tops of trees may have provided a refuge for mating. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.


Assuntos
Citrus/parasitologia , Proteção de Cultivos/métodos , Controle de Insetos/métodos , Mariposas , Polienos , Atrativos Sexuais , Animais , Feminino , Masculino , Polienos/administração & dosagem , Estações do Ano , Atrativos Sexuais/administração & dosagem
9.
Mar Drugs ; 13(11): 6962-76, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26610526

RESUMO

Hypoxia inducible factor-1α (HIF-1α) is an essential regulator of the cellular response to low oxygen concentrations, activating a broad range of genes that provide adaptive responses to oxygen deprivation. HIF-1α is overexpressed in various cancers and therefore represents a considerable chemotherapeutic target. Salternamide A (SA), a novel small molecule that is isolated from a halophilic Streptomyces sp., is a potent cytotoxic agent against a variety of human cancer cell lines. However, the mechanisms by which SA inhibits tumor growth remain to be elucidated. In the present study, we demonstrate that SA efficiently inhibits the hypoxia-induced accumulation of HIF-1α in a time- and concentration-dependent manner in various human cancer cells. In addition, SA suppresses the upstream signaling of HIF-1α, such as PI3K/Akt/mTOR, p42/p44 MAPK, and STAT3 signaling under hypoxic conditions. Furthermore, we found that SA induces cell death by stimulating G2/M cell cycle arrest and apoptosis in human colorectal cancer cells. Taken together, SA was identified as a novel small molecule HIF-1α inhibitor from marine natural products and is potentially a leading candidate in the development of anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Polienos/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Hipóxia Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Polienos/administração & dosagem , Polienos/isolamento & purificação , Alcamidas Poli-Insaturadas/administração & dosagem , Alcamidas Poli-Insaturadas/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Streptomyces/metabolismo , Fatores de Tempo
10.
Int J Oncol ; 47(5): 1954-62, 2015 11.
Artigo em Inglês | MEDLINE | ID: mdl-26352011

RESUMO

Manumycin A (Manu A) is a natural antibiotic produced by new Streptomyces strain, exhibiting antitumor and anticancer effects. However, the anticancer effects of Manu A on oral squamous cell carcinoma (OSCC) have not been reported. OSCC is an aggressive type of cancer because of its poor prognosis and low survival rate despite advanced medical treatment. We observed that Manu A reduced cell growth and Sp1 protein levels in OSCC cell lines (HN22 and HSC4) in a dose- and time-dependent manner. We also observed downregulation of Sp1 downstream target genes such as p27, p21, Mcl-1 and survivin. Moreover, nuclear staining with DAPI showed that Manu A was able to cause nuclear condensation and further fragmentation. Flow cytometry analyses using Annexin V and propiodium iodide supported Manu A-mediated apoptotic cell death of OSCC cells. Furthermore, Bcl-2 family such as mitochondrial pro­apoptotic Bax, anti-apoptotic Bcl-xl and Bid were regulated by Manu A, triggering the mitochondrial apoptotic pathway. In conclusion, these results indicate that Manu A is a potential to treat human OSCC via cell apoptosis through the downregulation of Sp1.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Polienos/administração & dosagem , Alcamidas Poli-Insaturadas/administração & dosagem , Fator de Transcrição Sp1/biossíntese , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Proteínas de Neoplasias/biossíntese , Polienos/química , Alcamidas Poli-Insaturadas/química , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição Sp1/genética , Streptomyces/química
11.
Med Princ Pract ; 24(1): 58-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25471106

RESUMO

OBJECTIVES: We aimed to investigate the effect of brief exposure to sub-cidal concentrations of nystatin, amphotericin B, ketoconazole, fluconazole and chlorhexidine gluconate on the adhesion of oral Candida dubliniensis isolates to the surface of acrylic dentures. METHODS: After determining the minimum inhibitory concentration of each drug, 20 oral isolates of C. dubliniensis were exposed to sub-cidal concentrations of the drugs for 1 h. The drugs were then removed by dilution, and the adhesion of the isolates to denture acrylic strips was assessed by an in vitro adhesion assay. RESULTS: Compared to the controls, exposure to nystatin, amphotericin B, ketoconazole, fluconazole and chlorhexidine gluconate suppressed the ability of C. dubliniensis isolates to adhere to acrylic denture surfaces with a reduction of 74.68, 74.27, 57.31, 44.57 and 56.53% (p < 0.001 for all drugs), respectively. CONCLUSIONS: Brief exposure to sub-cidal concentrations of anti-mycotics suppressed the adhesion of C. dubliniensis oral isolates to acrylic denture surfaces.


Assuntos
Anti-Infecciosos Locais/farmacologia , Azóis/farmacologia , Candida/efeitos dos fármacos , Clorexidina/farmacologia , Dentaduras/microbiologia , Polienos/farmacologia , Análise de Variância , Antifúngicos/farmacologia , Azóis/administração & dosagem , Clorexidina/administração & dosagem , Clínicas Odontológicas , Humanos , Kuweit , Testes de Sensibilidade Microbiana , Polienos/administração & dosagem , Polimetil Metacrilato
12.
Cold Spring Harb Perspect Med ; 5(5): a019653, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25384765

RESUMO

Successful treatment of infectious diseases requires choice of the most suitable antimicrobial agent, comprising consideration of drug pharmacokinetics (PK), including penetration into infection site, pathogen susceptibility, optimal route of drug administration, drug dose, frequency of administration, duration of therapy, and drug toxicity. Antimicrobial pharmacokinetic/pharmacodynamic (PK/PD) studies consider these variables and have been useful in drug development, optimizing dosing regimens, determining susceptibility breakpoints, and limiting toxicity of antifungal therapy. Here the concepts of antifungal PK/PD studies are reviewed, with emphasis on methodology and application. The initial sections of this review focus on principles and methodology. Then the pharmacodynamics of each major antifungal drug class (polyenes, flucytosine, azoles, and echinocandins) is discussed. Finally, the review discusses novel areas of pharmacodynamic investigation in the study and application of combination therapy.


Assuntos
Antifúngicos/administração & dosagem , Antifúngicos/farmacologia , Antifúngicos/farmacocinética , Micoses/tratamento farmacológico , Animais , Modelos Animais de Doenças , Equinocandinas/administração & dosagem , Equinocandinas/farmacocinética , Equinocandinas/farmacologia , Flucitosina/administração & dosagem , Flucitosina/farmacocinética , Flucitosina/farmacologia , Humanos , Camundongos , Polienos/administração & dosagem , Polienos/farmacocinética , Polienos/farmacologia , Coelhos , Ratos , Triazóis/administração & dosagem , Triazóis/farmacocinética , Triazóis/farmacologia
13.
Toxicon ; 90: 184-90, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25150200

RESUMO

Karlotoxins, polyketide derivatives produced by the dinoflagellate Karlodinium veneficum, are associated with fish kills in temperate estuaries world-wide. In this study, the acute effects of 3 pure karlotoxin analogs (KmTx 1, KmTx 3 and KmTx 2) have been examined in mice. Transient lethargy and increased respiratory rates were observed soon after dosing with the karlotoxins by intraperitoneal injection, but no deaths were recorded in animals dosed with KmTx 2 at up to 500 µg/kg or with KmTx 1 or KmTx 3 at up to 4000 µg/kg. Animals dosed intraperitoneally with KmTx 1 and KmTx 3 at 4000 µg/kg showed a pronounced decrease in food and water intake, lasting 3-4 days after dosing, accompanied by a significant decrease in body weight. After this time, the lost body weight was regained and the behavior and appearance of the mice remained normal throughout the following 10-day observation period. No effects were seen in mice dosed orally with KmTx 1 or KmTx 3 at a dose of 4000 µg/kg. It is concluded that contamination of seafood if it were to occur with these karlotoxins is unlikely to pose a major risk of acute intoxication in consumers.


Assuntos
Polienos/toxicidade , Piranos/toxicidade , Animais , Vias de Administração de Medicamentos , Feminino , Toxinas Marinhas , Camundongos , Polienos/administração & dosagem , Policetídeos , Piranos/administração & dosagem , Testes de Toxicidade Aguda
14.
Biomacromolecules ; 15(5): 1860-70, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24712760

RESUMO

Materials with fungi-bioinspired surface have been designed to host ergosterol-binding polyene antibiotics and to release them via a competitive mechanism only when fungi are present in the medium. Silicone rubber (SR) surfaces were endowed with selective loading and fungi-triggered release of polyene antifungal agents by means of a two-step functionalization that involved the grafting of glycidyl methacrylate (GMA) via a γ-ray preirradiation method (9-21.3% wt grafting) and the subsequent immobilization of ergosterol (3.9-116.8 mg/g) to the epoxy groups of polyGMA. The functionalized materials were characterized using FTIR and Raman spectroscopy, thermogravimetric analysis (TGA), and fluorescence, scanning electron microscopy (SEM), and atomic force microscopy (AFM) image analyses. Specific interactions between natamycin or nystatin and ergosterol endowed SR with ability to take up these polyene drugs, while immobilization of ergosterol did not modify the loading of antifungal drugs that did not interact in vivo with ergosterol (e.g., miconazole). In a buffer medium, polyene-loaded ergosterol-immobilized slabs efficiently retained the drug (<10% released at day 14), while in the presence of ergosterol-containing liposomes that mimic fungi membranes the release rate was 10-to-15-fold enhanced due to a competitive displacement of the drug from the ergosterol-immobilized slab to the ergosterol-containing liposomes. Release in the presence of cholesterol liposomes was slower due to a weaker interaction with polyene agents. The fungi-responsive release was demonstrated for both polyene drugs tested and for slabs prepared with a wide range of amounts of immobilized GMA and ergosterol, demonstrating the robustness of the approach. Nystatin-loaded functionalized slabs were challenged with Candida albicans and showed improved capability to inhibit biofilm formation compared to nystatin-soaked pristine SR, confirming the performance of the bioinspired materials.


Assuntos
Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Materiais Biomiméticos/química , Candida albicans/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Ergosterol/química , Polienos/química , Antifúngicos/química , Ligação Competitiva , Biofilmes/efeitos dos fármacos , Materiais Biomiméticos/administração & dosagem , Candida albicans/química , Candida albicans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Conformação Molecular , Polienos/administração & dosagem , Relação Estrutura-Atividade , Propriedades de Superfície
16.
J Gastroenterol Hepatol ; 28(10): 1616-23, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23730936

RESUMO

BACKGROUND AND AIM: The chemopreventive effect of RAS inhibitors on colorectal cancer is unknown. Because aberrant crypt foci (ACF), earliest preneoplastic lesions, are highly positive for K-RAS mutation, RAS inhibitors are likely to be effective for chemoprevention. Therefore, in the present study, the suppressive effect of a RAS inhibitor, manumycin A, on ACF formation in an azoxymethane (AOM)-induced rat colorectal carcinogenesis model was investigated. METHODS: Rats injected with AOM were administered manumycin A (30 mg/kg) subcutaneously thrice weekly for 8 weeks or for 4 weeks (latter half), sacrificed at 8 weeks, and examined for ACF in the colorectum. Phosphorylated ERK and Ki-67 expression was evaluated by immunohistochemistry. Apoptosis was assessed by TUNEL staining. RESULTS: The mean number of ACF in the 8-week manumycin A group (72.9 ± 20.1) was significantly lower than in the vehicle group (155.6 ± 56.7, P < 0.01), and it was significantly lower even in the 4-week manumycin A group than in the vehicle group (92.2 ± 13.0 vs 222.3 ± 83.3, P < 0.01). The positive rate for phosphorylated ERK in the manumycin A group (13.5 ± 19.2%) was significantly lower than in the vehicle group (50.2 ± 19.8%, P < 0.01). The positive rate for Ki-67 in the manumycin A group (2.2 ± 3.4%) was significantly lower than in the vehicle group (14.7 ± 8.2%, P < 0.01). There were significantly more terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling-positive cells in tissue samples from the manumycin A group versus the vehicle group (8.6 ± 9.7% vs 2.9 ± 2.0%, P < 0.05). CONCLUSION: Manumycin A suppressed ACF formation in the AOM-induced colorectal carcinogenesis model, demonstrating that RAS inhibitors may be very effective for chemoprevention of colorectal cancers.


Assuntos
Focos de Criptas Aberrantes/genética , Focos de Criptas Aberrantes/prevenção & controle , Azoximetano/farmacologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/prevenção & controle , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Farnesiltranstransferase/antagonistas & inibidores , Polienos/farmacologia , Polienos/uso terapêutico , Alcamidas Poli-Insaturadas/farmacologia , Alcamidas Poli-Insaturadas/uso terapêutico , Proteínas ras/antagonistas & inibidores , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/patologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Inibidores Enzimáticos/administração & dosagem , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Genes ras/genética , Injeções Subcutâneas , Antígeno Ki-67/metabolismo , Mutação , Fosforilação/efeitos dos fármacos , Polienos/administração & dosagem , Alcamidas Poli-Insaturadas/administração & dosagem , Ratos , Ratos Endogâmicos F344
17.
Rev. bras. oftalmol ; 72(2): 132-141, mar.-abr. 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-678383

RESUMO

O tratamento das infecções oculares por fungos representa um desafio à prática oftalmológica. Para obtermos resposta terapêutica adequada, além do uso da droga correta, é necessária a administração desta de forma eficaz. Este manuscrito reúne informações a respeito das principais drogas antifúngicas utilizadas em infecções oculares, suas concentrações e principais vias de administração.


Treatment of fungal eye infections represents a challenge to the ophthalmology practice. For an adequate therapeutic response, besides correct drug choice, it is necessary an effectively administration. This script gathers information about the major antifungal drugs used in eye infections, their concentrations and main administration routes.


Assuntos
Humanos , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Interações Medicamentosas , Infecções Oculares Fúngicas/tratamento farmacológico , Azóis/administração & dosagem , Azóis/uso terapêutico , Equinocandinas/administração & dosagem , Equinocandinas/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/uso terapêutico , Polienos/administração & dosagem , Polienos/uso terapêutico
18.
Mar Drugs ; 10(11): 2388-402, 2012 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23203266

RESUMO

Capoamycin-type antibiotics (2-5) and polyene acids (6, 7) were isolated from marine Streptomyces fradiae strain PTZ0025. Their structures were established by extensive nuclear magnetic resonance (NMR) and high resolution electron spray ionization mass spectroscopy (HRESIMS) analyses and chemical degradation. Compounds 3, 4, 6, 7 were found to be new and named as fradimycins A (3) and B (4), and fradic acids A (6) and B (7). Compounds 3-5 showed in vitro antimicrobial activity against Staphylococcus aureus with a minimal inhibitory concentration (MIC) of 2.0 to 6.0 µg/mL. Interestingly, Compounds 3-5 also significantly inhibited cell growth of colon cancer and glioma with IC50 values ranging from 0.13 to 6.46 µM. Fradimycin B (4), the most active compound, was further determined to arrest cell cycle and induce apoptosis in tumor cells. The results indicated that fradimycin B (4) arrested the cell cycle at the G0/G1 phase and induced apoptosis and necrosis in colon cancer and glioma cells. Taken together, the results demonstrated that the marine natural products 3-5, particularly fradimycin B (4), possessed potent antimicrobial and antitumor activities.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Polienos/farmacologia , Streptomyces/química , Animais , Antraquinonas/administração & dosagem , Antraquinonas/isolamento & purificação , Antraquinonas/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/isolamento & purificação , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Glioma/tratamento farmacológico , Glioma/patologia , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Polienos/administração & dosagem , Polienos/isolamento & purificação , Ratos , Espectrometria de Massas por Ionização por Electrospray , Staphylococcus aureus/efeitos dos fármacos
19.
Clin Infect Dis ; 54 Suppl 1: S73-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22247449

RESUMO

The high mortality rate of mucormycosis with currently available monotherapy, particularly in hematology patients, has stimulated interest in studying novel combinations of antifungal agents to determine whether superior outcomes might be achieved. Combination lipid polyene-echinocandin therapy is the most promising of such regimens based on safety profile, the availability of parenteral formulations of echinocandins, their synergy in murine models of mucormycosis, and observational clinical data that are concordant. Other options include combination lipid polyene plus deferasirox or posaconazole therapy. Definitive, randomized, placebo-controlled phase III clinical trials are needed to determine whether combination therapy with any of these options is superior to monotherapy. Until such studies are conducted, clinicians will continue to be placed in the unacceptable position of not knowing if and when to administer combination therapy. Such a state of confusion may lead to undertreatment if combination therapy is indeed superior but is not used and, conversely, may lead to unacceptable toxicity and cost to patients if combination therapy is not superior but is used. It is critical that sponsors step forward with funding to conduct these clinical trials to determine whether outcomes from these devastating infections can be improved.


Assuntos
Benzoatos/uso terapêutico , Equinocandinas/uso terapêutico , Mucormicose/tratamento farmacológico , Polienos/uso terapêutico , Triazóis/uso terapêutico , Animais , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Benzoatos/administração & dosagem , Ensaios Clínicos como Assunto , Deferasirox , Quimioterapia Combinada , Equinocandinas/administração & dosagem , Humanos , Lipídeos/administração & dosagem , Lipídeos/uso terapêutico , Camundongos , Mucormicose/microbiologia , Polienos/administração & dosagem , Resultado do Tratamento , Triazóis/administração & dosagem
20.
Immunol Lett ; 141(1): 68-73, 2011 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-21839115

RESUMO

New polyene macrolide antibiotic SJA-95 in free as well as liposomal (lip.) forms, with and without interferon-γ (IFN-γ) was studied in mice model of aspergillosis using biological and biochemical parameters viz. colony forming units (CFU) in liver, spleen, kidney, lung and brain, and serum IgG, and interleukin-4 (IL-4). Treatment with free and lip SJA-95 along with IFN-γ prolonged the survival time, reduced CFU in vital organs, decreased serum IgG and IL-4 levels. SJA-95 lip form showed greater antifungal activity as compared to free form. The combined treatment of lip SJA-95 with IFN-γ showed further enhancement in antifungal activity of SJA-95 (lip). The present experimental findings demonstrated IFN-γ might act as a potent modulator in immune reaction during fungal infection and can be a useful adjunctive in antifungal therapy in the management of deep seated systemic mycoses.


Assuntos
Antifúngicos/administração & dosagem , Aspergilose , Imunomodulação/efeitos dos fármacos , Interferon gama/administração & dosagem , Macrolídeos/administração & dosagem , Polienos/administração & dosagem , Animais , Aspergilose/tratamento farmacológico , Aspergilose/imunologia , Imunoglobulina G/sangue , Interleucina-4/sangue , Lipossomos/administração & dosagem , Fígado/microbiologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Baço/microbiologia
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