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1.
Toxicol Appl Pharmacol ; 434: 115796, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34785274

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has required the urgent development of new therapies, among which passive immunotherapy is contemplated. CoviFab (INM005) is a RBD-specific F(ab')2 fragment derived from equine polyclonal antibodies. We investigate their preclinical security and biodistribution by in vivo and ex vivo NIR imaging after intravenous administration of a dose of 4 mg/kg at time 0 and 48 h. Images were taken at 1, 12, 24, 36, 48, 49, 60, 72, 84, 96, 108, 120, 132 and 144 h after the first intravenous injection. At 96 and 144 h, mice were sacrificed for haematology, serum chemistry, clinical pathology, histopathology and ex vivo imaging. The biodistribution profile was similar in all organs studied, with the highest fluorescence at 1 h after each injection, gradually decreasing after that each one and until the end of the study (144 h). The toxicology study revealed no significant changes in the haematology and serum chemistry parameters. Further, there were no changes in the gross and histological examination of organs. Nonclinical data of the current study confirm that CoviFab is safe, without observable adverse effects in mice. Furthermore, we confirm that bioimaging studies are a useful approach in preclinical trials to determine biodistribution.


Assuntos
Anticorpos Antivirais/metabolismo , Tratamento Farmacológico da COVID-19 , Receptores Imunológicos/metabolismo , Proteínas Recombinantes/metabolismo , SARS-CoV-2/metabolismo , Administração Intravenosa , Animais , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/efeitos adversos , COVID-19/metabolismo , COVID-19/prevenção & controle , Células HEK293 , Cavalos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Receptores Imunológicos/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , SARS-CoV-2/efeitos dos fármacos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
2.
Int J Nanomedicine ; 16: 2187-2201, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33758506

RESUMO

The physicochemical and optical properties of silver nanoparticles (SNPs) and gold nanoparticles (GNPs) have allowed them to be employed for various biomedical applications, including delivery, therapy, imaging, and as theranostic agents. However, since they are foreign body systems, they are usually redistributed and accumulated in some vital organs, which can produce toxic effects; therefore, this a crucial issue that should be considered for potential clinical trials. This review aimed to summarize the reports from the past ten years that have used SNPs and GNPs for in vivo studies on the diagnosis and treatment of brain diseases and those related to the central nervous system, emphasizing their toxicity as a crucial topic address. The article focuses on the effect of the nanoparticle´s size and chemical composition as relevant parameters for in vivo toxicity. At the beginning of this review, the general toxicity and distribution studies are discussed separately for SNPs and GNPs. Subsequently, this manuscript analyzes the principal applications of both kinds of nanoparticles for glioma, neurodegenerative, and other brain diseases, and discusses the advances in clinical trials. Finally, we analyze research prospects towards clinical applications for both types of metallic nanoparticles.


Assuntos
Doenças do Sistema Nervoso Central/patologia , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Prata/química , Testes de Toxicidade , Animais , Humanos , Nanopartículas Metálicas/ultraestrutura , Distribuição Tecidual/efeitos dos fármacos
3.
AAPS PharmSciTech ; 22(3): 115, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33763814

RESUMO

Nanomedicine is a highly demanded discipline. Liposomes have seen an increased attention due to their physicochemical properties that allow them to act as nanocarriers of drugs and also of radioisotopes that can be used to diagnose and treat cancer. In order to obtain a novel permeability cancer imaging agent based on 99mTc-labeled liposomes, we describe microwave-assisted synthesis of stearyl 6-(benzylidenehydrazinyl) nicotinamide lipid, which was included in two formulations: nanometric hydrazinonicotinic acid (HYNIC) liposome and its PEGylated coated analogue, HYNIC-PEG liposome. Radiolabeling with 99mTc via stearyl 6-(benzylidenehydrazinyl) nicotinamide was found to be easy, reproducible, and stable, revealing high radiochemical purity (94 ± 1.7%) for both liposomal formulations. Biodistribution at 4 h and 24 h and scintigraphic images at 4 h were performed in normal and melanoma-bearing C57BL/6 mice. Biodistribution studies at 4 h showed tumor uptake of 99mTc-HYNIC liposome and 99mTc-HYNIC-PEG liposome (1.1 ± 0.6 and 2.5 ± 0.4, respectively) and also at 24 h p.i. (1.8 ± 0.5 and 3.0 ± 1.1, respectively). Scintigraphic images showed appreciable tumor uptake in melanoma tumor-bearing mice with both liposomal formulations. Our results show that 99mTc stearyl 6-(benzylidenehydrazinyl) nicotinamide liposomes can be used as diagnostic noninvasive in vivo tumor-targeting agents capable of evaluating tumor permeability and development who can be used in personalized chemotherapy planning.


Assuntos
Melanoma Experimental/metabolismo , Niacinamida/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Tecnécio/farmacocinética , Animais , Linhagem Celular Tumoral , Lipossomos , Melanoma Experimental/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Niacinamida/administração & dosagem , Niacinamida/química , Permeabilidade/efeitos dos fármacos , Cintilografia/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/química , Tecnécio/administração & dosagem , Tecnécio/química , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/fisiologia
4.
ACS Chem Neurosci ; 11(3): 427-435, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31898886

RESUMO

Development of positron emission tomography (PET) imaging agents capable of quantifying tau aggregates in neurodegenerative disorders such as Alzheimer's disease (AD) is of enormous importance in the field of dementia research. The aim of the present study was to conduct first-in-man imaging studies with the potential novel tau imaging agent [18F]N-methyl lansoprazole ([18F]NML). Herein we report validation of the synthesis of [18F]NML for clinical use by labeling the trifluoromethyl group via radiofluorination of the corresponding gem-difluoro enol ether precursor. This is the first use of this method for clinical production of PET radiotracers and confirmed that it can be readily implemented at multiple production facilities to provide [18F]NML in good noncorrected radiochemical yield (3.4 ± 1.5 GBq, 4.6% ± 2.6%) and molar activity (120.1 ± 186.3 GBq/µmol), excellent radiochemical purity (>97%), and suitable for human use (n = 15). With [18F]NML in hand, we conducted rodent biodistribution, estimates of human dosimetry, and preliminary evaluation of [18F]NML in human subjects at two imaging sites. Healthy controls (n = 4) and mildly cognitively impaired (MCI) AD patients (n = 6) received [18F]NML (tau), [18F]AV1451 (tau), and [18F]florbetaben or [18F]florbetapir (amyloid) PET scans. A single progressive supranuclear palsy (PSP) patient also received [18F]NML and [18F]AV1451 PET scans. [18F]NML showed good brain uptake, reasonable pharmacokinetics, and appropriate imaging characteristics in healthy controls. The mean ± SD of the administered mass of [18F/19F]NML was 2.01 ± 2.17 µg (range, 0.16-8.27 µg) and the mean administered activity was 350 ± 62 MBq (range, 199-403 MBq). There were no adverse or clinically detectable pharmacologic effects in any of the 11 subjects, and no significant changes in vital signs were observed. However, despite high affinity for tau in vitro, brain retention in MCI/AD and PSP patients was low, and there was no evidence of specific signals in vivo that corresponded to tau. Although it is still unclear why clinical translation of the radiotracer was unsuccessful, we nevertheless conclude that further development of [18F]NML as a tau PET imaging agent is not warranted at this time.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Compostos de Anilina/farmacologia , Disfunção Cognitiva/diagnóstico por imagem , Etilenoglicóis/farmacologia , Lansoprazol/farmacologia , Distribuição Tecidual/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos
5.
Biomed Pharmacother ; 118: 109323, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400669

RESUMO

Long circulating pH-sensitive liposomes have been shown to effectively deliver doxorubicin (DOX) to tumors and reduce its toxic effects. Folic acid receptors are upregulated in a wide variety of solid, epithelial tumors, including breast cancer. In order to improve liposomal endocytosis and antitumor activity, folic acid has been added to nanoparticles surfaces to exploit overexpression of folate receptors in tumor cells. The purpose of this study was to evaluate the antitumor activity in vitro and in vivo of long circulating pH-sensitive folate-coated DOX-loaded liposomes (SpHL-DOX-Fol) in a 4T1 breast cancer model system in vitro and in vivo. Biodistribution studies were performed and in vivo electrocardiographic parameters were evaluated. A higher tumor uptake for radiolabeled SpHL-Fol (99mTc-SpHL-Fol) 4 h after intravenous administration was observed in comparision with non-folate-coated liposomes (99mTc-SpHL). Antitumor activity showed that SpHL-DOX-Fol treatment led to a 68% growth arrest and drastically reduce pulmonary metastasis foci. Additionally, eletrocardiographic parameters analysis revealed no dispersion in the QT and QTc interval was observed in liposomal treated mice. In summary, this novel multifunctional nanoplatform deomonstrated higher tumor uptake and antitumor activity. SpHL-DOX-Fol represents a drug delivery platform to improve DOX tumor delivery and reduce dose-limiting toxicity.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/uso terapêutico , Ácido Fólico/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/ultraestrutura , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Doxorrubicina/sangue , Doxorrubicina/farmacologia , Feminino , Concentração de Íons de Hidrogênio , Lipossomos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Distribuição Tecidual/efeitos dos fármacos
6.
Eur J Drug Metab Pharmacokinet ; 44(1): 111-120, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30132264

RESUMO

BACKGROUND: Amblyomin-X is a recombinant protein under development for cancer treatment owing to its selective cytotoxic activity over several tumour cell lines and tumour regression in mice models. The aim of this study was to examine the distribution and pharmacokinetics of amblyomin-X in healthy female mice. METHODS: Amblyomin-X was injected intravenously into the healthy animals and at controlled times plasma and organs were removed and analysed for identification and quantification of the protein. Alternatively, the labelled protein was injected into mice and tracked in an in vivo imaging system. RESULTS: Amblyomin-X was rapidly eliminated from plasma, probably because of its inability to bind to plasma albumin. After 10 min, the protein was found in the thymus and lungs, and later in the heart, liver and kidneys. In the liver, the protein was found until 24 h after a single injection. The in vivo analysis showed the same kinetics profile, besides the identification of amblyomin-X in the bladder region, indicating its elimination via urine. Only fragments of amblyomin-X were observed in the urine. CONCLUSIONS: These findings suggest that amblyomin-X is rapidly distributed to the tissues, metabolized by the liver or even kidneys, and eliminated in urine in healthy mice. There is no accumulation in any organ.


Assuntos
Antineoplásicos/farmacocinética , Inibidores do Fator Xa/farmacocinética , Proteínas e Peptídeos Salivares/farmacocinética , Administração Intravenosa , Sequência de Aminoácidos , Animais , Antineoplásicos/administração & dosagem , Proteínas de Artrópodes , Inibidores do Fator Xa/administração & dosagem , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas e Peptídeos Salivares/administração & dosagem , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
7.
Adv Rheumatol ; 59: 20, 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1088591

RESUMO

Abstract Background: To date there are no specific classification criteria for childhood-onset systemic lupus erythematosus (cSLE). This study aims to compare the performance among the American College of Rheumatology (ACR) 1997, the Systemic Lupus International Collaborating Clinics criteria (SLICC) and the new European League Against Rheumatism (EULAR)/ACR criteria, in a cSLE cohort. Methods: We conducted a medical chart review study of cSLE cases and controls with defined rheumatic diseases, both ANA positive, to establish each ACR1997, SLICC and EULAR/ACR criterion fulfilled, at first visit and 1-year-follow-up. Results: Study population included 122 cSLE cases and 89 controls. At first visit, SLICC criteria had higher sensitivity than ACR 1997 (89.3% versus 70.5%, p < 0.001), but similar specificity (80.9% versus 83.2%, p = 0.791), however performance was not statistically different at 1-year-follow-up. SLICC better scored in specificity compared to EULAR/ACR score ≥ 10 at first visit (80.9% versus 67.4%, p = 0.008) and at 1-year (76.4% versus 58.4%, p = 0.001), although sensitivities were similar. EULAR/ACR criteria score ≥ 10 exhibited higher sensitivity than ACR 1997 (87.7% versus 70.5%, p < 0.001) at first visit, but comparable at 1-year, whereas specificity was lower at first visit (67.4% versus 83.2%, p = 0.004) and 1-year (58.4% versus 76.4%, p = 0.002). A EULAR/ACR score ≥ 13 against a score ≥ 10, resulted in higher specificity, positive predictive value, and cut-off point accuracy. Compared to SLICC, a EULAR/ACR score ≥ 13 resulted in lower sensitivity at first visit (76.2% versus 89.3%, p < 0.001) and 1-year (91% versus 97.5%, p = 0.008), but similar specificities at both assessments. When compared to ACR 1997, a EULAR/ACR total score ≥ 13, resulted in no differences in sensitivity and specificity at both observation periods. Conclusions: In this cSLE population, SLICC criteria better scored at first visit and 1-year-follow-up. The adoption of a EULAR/ACR total score ≥ 13 in this study, against the initially proposed ≥10 score, was most appropriate to classify cSLE. Further studies are necessary to address if SLICC criteria might allow fulfillment of cSLE classification earlier in disease course and may be more inclusive of cSLE subjects for clinical studies.


Assuntos
Animais , Humanos , Encéfalo/metabolismo , Preparações Farmacêuticas/metabolismo , Barreira Hematoencefálica/metabolismo , Distribuição Tecidual/fisiologia , Modelos Teóricos , Aracnoide-Máter/efeitos dos fármacos , Aracnoide-Máter/metabolismo , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Encéfalo/efeitos dos fármacos , Preparações Farmacêuticas/administração & dosagem , Barreira Hematoencefálica/efeitos dos fármacos , Distribuição Tecidual/efeitos dos fármacos , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo
8.
Drug Deliv ; 25(1): 1585-1594, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30044149

RESUMO

Voriconazole (VCZ), a triazole with a large spectrum of action is one of the most recommended antifungal agents as the first line therapy against several clinically important systemic fungal infections, including those by Candida albicans. This antifungal has moderate water solubility and exhibits a nonlinear pharmacokinetic (PK) profile. By entrapping VCZ into liposomes, it is possible to circumvent certain downsides of the currently available product such as a reduction in the rate of its metabolization into an inactive form, avoidance of the toxicity of the sulfobutyl ether-beta-cyclodextrin (SBECD), vehicle used to increase its solubility. PKs and biodistribution of VCZ modified by encapsulation into liposomes resulted in improved antifungal activity, due to increased specificity and tissue penetration. In this work, liposomal VCZ resulted in AUC0-24/MIC ratio of 53.51 ± 11.12, whereas VFEND® resulted in a 2.5-fold lower AUC0-24/MIC ratio (21.51 ± 2.88), indicating favorable antimicrobial systemic activity. VCZ accumulation in the liver and kidneys was significantly higher when the liposomal form was used. Protection of the drug from biological degradation and reduced rate of metabolism leads to a 30% reduction of AUC of the inactive metabolite voriconazole-N-oxide (VNO) when the liposomal drug was administered. Liposomal VCZ presents an alternative therapeutic platform, leading to a safe and effective treatment against systemic fungal infections.


Assuntos
Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Voriconazol/administração & dosagem , Voriconazol/farmacocinética , Administração Intravenosa , Animais , Antifúngicos/química , Aspergillus/efeitos dos fármacos , Aspergillus/fisiologia , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Candidíase/tratamento farmacológico , Candidíase/metabolismo , Composição de Medicamentos , Humanos , Lipossomos , Masculino , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana/métodos , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia , Voriconazol/química
9.
Biomed Pharmacother ; 103: 1567-1576, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29864944

RESUMO

BACKGROUND: Studies have showed the protective effects of conjugated linoleic acid (CLA) on intestinal epithelium, modulating host immune and inflammatory responses on intestinal diseases. OBJECTIVE: To evaluate the preventive effects of CLA on the intestinal mucositis induced by 5-FU in a murine model. METHODS: Sixty-four BALB/c mice were randomly divided into four groups: Control (CTL), fed a standard chow diet; CLAs, fed a diet supplemented with CLA; Mucositis (5-FU), fed a standard chow diet and underwent mucositis induction and CLAs 5-FU, fed a diet supplemented with CLA and underwent mucositis induction. Mucositis was induced by intraperitoneal injection of 300 mg/kg 5-FU. After 72 h, the animals were euthanized and intestinal permeability, bacterial translocation, inflammatory mediators, and intestinal histology were evaluated. RESULTS: Mice in the CLAs 5-FU group showed reduced weight loss compared to those in the 5-FU group (p < 0.005). Furthermore, the results also showed that the treatment with CLA reduced intestinal permeability, bacterial translocation, and biomarkers of inflammatory response besides minor damage to ZO-1 and occludin with maintenance of the integrity of the intestinal epithelium and a favorable balance between the inflammatory and regulatory cytokines. CONCLUSION: This study suggests that CLA reduced the adverse effects from 5-FU administration on the intestinal mucosa.


Assuntos
Fluoruracila/efeitos adversos , Intestinos/patologia , Ácidos Linoleicos Conjugados/uso terapêutico , Mucosite/tratamento farmacológico , Mucosite/prevenção & controle , Animais , Translocação Bacteriana/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Quimiocinas/metabolismo , Modelos Animais de Doenças , Comportamento Alimentar , Imunoglobulina A/metabolismo , Inflamação/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Ácidos Linoleicos Conjugados/farmacologia , Masculino , Camundongos Endogâmicos BALB C , Mucosite/microbiologia , Mucosite/patologia , Distribuição Tecidual/efeitos dos fármacos
10.
Biometals ; 31(4): 517-525, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29574625

RESUMO

Tumorigenic cell lines are more susceptible to [Re6Se8I6]3- cluster-induced death than normal cells, becoming a novel candidate for cancer treatment. Still, the feasibility of using this type of molecules in human patients remains unclear and further pharmacokinetics analysis is needed. Using coupled plasma optical emission spectroscopy, we determined the Re-cluster tissue content in injected mice, as a biodistribution measurement. Our results show that the Re-cluster successfully reaches different tissues, accumulating mainly in heart and liver. In order to dissect the mechanism underlying cluster biodistribution, we used three different experimental approaches. First, we evaluate the degree of lipophilicity by determining the octanol/water partition coefficient. The cluster mostly remained in the octanol fraction, with a coefficient of 1.86 ± 0.02, which indicates it could potentially cross cell membranes. Then, we measured the biological membrane penetration through a parallel artificial membrane permeability assays (PAMPA) assay. The Re-cluster crosses the artificial membrane, with a coefficient of 122 nm/s that is considered highly permeable. To evaluate a potential application of the Re-cluster in central nervous system (CNS) tumors, we analyzed the cluster's brain penetration by exposing cultured blood-brain-barrier (BBB) cells to increasing concentrations of the cluster. The Re-cluster effectively penetrates the BBB, reaching nearly 30% of the brain side after 24 h. Thus, our results indicate that the Re-cluster penetrates biological membranes reaching different target organs-most probably due to its lipophilic properties-becoming a promising anti-cancer drug with high potential for CNS cancer's diagnosis and treatment.


Assuntos
Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Complexos de Coordenação/farmacologia , Rênio/farmacologia , Transporte Biológico/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Neoplasias do Sistema Nervoso Central/metabolismo , Neoplasias do Sistema Nervoso Central/patologia , Humanos , Selênio/farmacologia , Distribuição Tecidual/efeitos dos fármacos
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