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1.
Anal Biochem ; 642: 114557, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35092720

RESUMO

Cyanobacteriochromes are the extended family of phytochrome photosensors characterized in cyanobacteria. Alr1966g2C56A is a cyanobacteriochrome mutant of Alr1966g2 in Nostoc sp. PCC 7120 from freshwater. In this paper, we truncated ten residues in the N-terminus and ten residues in the C-terminus of Alr1966g2C56A and obtained truncated Alr1966g2C46A, termed as Alr1966g2C46A-tr. Alr1966g2C46A-tr binded covalently not only phycocyanobilin but also biliverdin via Cys74 of the conserved CH motif, and showed a significant improvement in binding-PCB efficiency in E. coli, compared with that of untruncated Alr1966g2C56A. We also captured a persistent red fluorescence of Alr1966g2C46A-tr-PCB or Alr1966g2C46A-tr-BV expressed in live E. coli. Thus, Alr1966g2C46A-tr was suitable for the stable red fluorescent probe as a starting material.


Assuntos
Biliverdina/química , Cianobactérias/química , Proteínas Luminescentes/análise , Ficobilinas/química , Ficocianina/química , Fitocromo/química , Proteína Vermelha Fluorescente
2.
J Endocrinol ; 248(2): 145-154, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33258802

RESUMO

Glucagon-like peptide 1 (GLP-1) is an insulinotropic hormone and plays an important role in regulating glucose homeostasis. GLP-1 has a short half-life (t1/2 < 2 min) due to degrading enzyme dipeptidyl peptidase-IV and rapid kidney clearance, which limits its clinical application as a therapeutic reagent. We demonstrated recently that supaglutide, a novel GLP-1 mimetic generated by recombinant fusion protein techniques, exerted hypoglycemic and ß-cell trophic effects in type 2 diabetes db/db mice. In the present study, we examined supaglutide's therapeutic efficacy and pharmacokinetics in diabetic rhesus monkeys. We found that a single subcutaneous injection of supaglutide of tested doses transiently and significantly reduced blood glucose levels in a dose-dependent fashion in the diabetic monkeys. During a 4-week intervention period, treatment of supaglutide of weekly dosing dose-dependently decreased fasting and random blood glucose levels. This was associated with significantly declined plasma fructosamine levels. The repeated administration of supaglutide remarkably also decreased body weight in a dose-dependent fashion accompanied by decreased food intake. Intravenous glucose tolerance test results showed that supaglutide improved glucose tolerance. The intervention also showed enhanced glucose-stimulated insulin secretion and improved lipid profile in diabetic rhesus monkeys. These results reveal that supaglutide exerts beneficial effects in regulating blood glucose and lipid homeostasis in diabetic rhesus monkeys.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Avaliação Pré-Clínica de Medicamentos , Insulina/sangue , Secreção de Insulina/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Macaca mulatta , Masculino
3.
ACR Open Rheumatol ; 2(3): 147-157, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32037683

RESUMO

OBJECTIVE: To qualitatively explore the processes through which the Chronic Disease Self-Management Program (CDSMP)-a peer-led, group-based educational intervention for people with chronic conditions-affects self-management behaviors among African American women with systemic lupus erythematosus (SLE). METHODS: Using a longitudinal pre- and postintervention design, we conducted two waves of one-on-one, semistructured interviews with 24 purposefully sampled participants. Wave 1 interviews explored self-management behaviors at baseline; wave 2 interviews focused on changes in these behaviors postintervention. Transcripts were analyzed using thematic analysis methods. RESULTS: Study participants perceived the CDSMP to be a valuable resource that helped them improve fundamental self-management behaviors, including exercise, relaxation, diet, and medication adherence. We found, with few exceptions, that in this sample, women's reported changes in self-management behaviors did not vary by participant age, education, SLE disease severity, or depression status. Our analysis suggests that the CDSMP had the most widespread perceived effects on relaxation and exercise. Strategies that generated improvements in relaxation and exercise included goal setting, action planning, encouragement to pursue low-impact physical activity, and introduction of mindfulness techniques to better manage SLE symptoms. CONCLUSION: Our findings suggest that African American women with SLE perceived the CDSMP as an effective educational self-management intervention. The program can potentially catalyze improvements in self-management behaviors in this population, regardless of demographic or disease characteristics.

4.
Arthritis Res Ther ; 21(1): 155, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31238992

RESUMO

BACKGROUND: Healthcare access, utilization, and quality play critical roles in shaping mortality and morbidity among patients diagnosed with systemic lupus erythematosus (SLE), and yet healthcare access, utilization, and quality can be suboptimal for many people living with SLE. The aim of this qualitative study was to explore the perceived impact of a peer-led, group-based educational intervention (the Chronic Disease Self-Management Program [CDSMP]) on healthcare engagement behaviors among African American women with SLE. METHODS: Participants were recruited from the WELL (Women Empowered to Live with Lupus) study, a behavioral trial of the effectiveness of the CDSMP on African American women diagnosed with SLE. We conducted two waves of qualitative, one-on-one, semi-structured interviews with 24 purposively sampled WELL participants; one interview was conducted before CDSMP participation and one after. Wave 1 interviews explored health service use behaviors at baseline; Wave 2 interviews focused on changes in these behaviors post-intervention and women's perceptions of whether and how the CDSMP shaped these changes. Transcripts were analyzed using thematic analysis methods. RESULTS: Study participants perceived the CDSMP to be a valuable resource for supporting two distinct health service use behaviors: communicating with doctors (N = 16 [88.9%]) and managing medication side effects (N = 17 [41.2%]). Women perceived that the CDSMP had the most potent and widespread effects on patients' communication with doctors. Strategies that women believed generated improvements in patient-doctor communication included enhancing preparation for appointments and boosting patient participation during doctor's visits. Women's reported post-CDSMP improvements in health service use behaviors varied by disease severity and depression. Insurance coverage, while not probed directly during baseline interviews, emerged organically as a key factor affecting health service use behaviors; the CDSMP did not seem to improve participants' ability to circumvent insurance-related barriers to accessing care. CONCLUSIONS: Our findings suggest that the CDSMP may help enhance healthcare service utilization among African American women with SLE by improving doctor/patient communication and medication side effect management. If future research confirms this conclusion, African American women living with SLE should be encouraged to participate in CDSMP workshops to enhance health service use behaviors. TRIAL REGISTRATION: NCT02988661 . Registered 12/07/2016.


Assuntos
Negro ou Afro-Americano , Lúpus Eritematoso Sistêmico/terapia , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Participação do Paciente/métodos , Qualidade de Vida , Autogestão/métodos , Saúde da Mulher , Adulto , Feminino , Humanos , Incidência , Lúpus Eritematoso Sistêmico/etnologia , Pessoa de Meia-Idade , Projetos Piloto , Estados Unidos/epidemiologia
5.
Int J Nanomedicine ; 14: 1359-1383, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863066

RESUMO

Slp forms a crystalline array of proteins on the outermost envelope of bacteria and archaea with a molecular weight of 40-200 kDa. Slp can self-assemble on the surface of liposomes in a proper environment via electrostatic interactions, which could be employed to functionalize liposomes by forming Slp-coated liposomes for various applications. Among the molecular characteristics, the stability, adhesion, and immobilization of biomacromolecules are regarded as the most meaningful. Compared to plain liposomes, Slp-coated liposomes show excellent physicochemical and biological stabilities. Recently, Slp-coated liposomes were shown to specifically adhere to the gastrointestinal tract, which was attributed to the "ligand-receptor interaction" effect. Furthermore, Slp as a "bridge" can immobilize functional biomacromol-ecules on the surface of liposomes via protein fusion technology or intermolecular forces, endowing liposomes with beneficial functions. In view of these favorable features, Slp-coated liposomes are highly likely to be an ideal platform for drug delivery and biomedical uses. This review aims to provide a general framework for the structure and characteristics of Slp and the interactions between Slp and liposomes, to highlight the unique properties and drug delivery as well as the biomedical applications of the Slp-coated liposomes, and to discuss the ongoing challenges and perspectives.


Assuntos
Tecnologia Biomédica/métodos , Sistemas de Liberação de Medicamentos , Lipossomos/química , Glicoproteínas de Membrana/química , Lipossomos/ultraestrutura , Eletricidade Estática
6.
Int J Pharm ; 529(1-2): 227-237, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28684365

RESUMO

S-layer proteins (Slps) are crystalline arrays of protein on bacterial cell surface layers. Owning to their capability to reassemble on the surface of lipid layers, Slps have been employed to modify liposomes for various profits. But the interaction information between Slps and positively charged liposomes are destitute, especially the gastrointestinal adhesion of Slps-coating liposomes is rarely reported. In the present work, the Slps extracted from Lactobacillus helveticus were reassembled on the surface of novel positively charged liposomes composed of soybean lecithin, Eudragit®RL100 and cholesterol. The particle size and remarkable changes of Zeta potential with various Slps/lipid weight ratios were determined by dynamic light scattering and phase analysis light scattering. Significant difference in fluorescence dequenching percentage of liposomes decorated by ODA-FITC confirmed Slps self-reassemble on the surface of liposomes. A higher integrity of vesicular membrane after the addition of Triton X-100 solution demonstrated the stability enhancement of Slps-coating liposomes. Fourier transform infrared (FTIR) spectroscopy illustrated the interaction came from non-covalent bond. The mucoadhesion of Slps-coating liposomes was evaluated by the resident FITC-LP on the gastric and intestinal tract of mice at 7h and 12h after intragastrical administration, which proved that the Slps-coating improved the gastrointestinal adhesion significantly.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Lipossomos/química , Glicoproteínas de Membrana/química , Animais , Camundongos , Camundongos Endogâmicos BALB C , Octoxinol , Tamanho da Partícula
7.
Sci Rep ; 7: 43036, 2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28225062

RESUMO

Liposome (LP) encapsulation of doxorubicin (DOX) is a clinically validated method for cancer drug delivery, but its cellular uptake is actually lower than the free DOX. Therefore, we modified DOX-LP with a cationic polymer (Eudragit RL100; ER) to improve its cellular uptake and antitumor activity. The resulting DOX-ERLP was a 190 nm nanoparticle that was absorbed efficiently and caused cancer cell death in 5 hrs. Growth as measured by the MTT assay or microscopic imaging demonstrated that DOX-ERLP has at least a two-fold greater potency than the free DOX in inhibiting the growth of a DOX resistant (MCF7/adr) cell and an aggressive liver cancer H22 cell. Further, its in vivo efficacy was tested in H22-bearing mice, where four injections of DOX-ERLP reduced the tumor growth by more than 60% and caused an average of 60% tumor necrosis, which was significantly better than the DOX and DOX-LP treated groups. Our work represents the first use of polymethacrylate derivatives for DOX liposomal delivery, demonstrating the great potential of cationic polymethacrylate modified liposomes for improving cancer drug delivery.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Doxorrubicina/química , Lipossomos/química , Ácidos Polimetacrílicos/química , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Cátions/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Humanos , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Tamanho da Partícula
8.
AAPS PharmSciTech ; 18(2): 509-516, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27120090

RESUMO

Nanostructured lipid carriers (NLCs) are interesting delivery systems for enhancing the penetration of an active substance through the skin after topical administration. The present paper described the development of a novel NLCs for minoxidil (MXD) topical delivery. Stearic acid and oleic acid that showed the highest solubility for MXD were selected as solid lipid and liquid lipid, respectively, and the NLCs were prepared by hot high pressure homogenization method. The minoxidil loaded NLCs prepared accordingly to the optimal formulation exhibited spherical shape with a mean diameter of 281.4 ± 7.4 nm, polydispersity of 0.207 ± 0.009, zeta potential of -32.90 ± 1.23 mV, drug entrapment efficiency of 92.48 ± 0.31%, and drug loading of 13.85 ± 0.47%. Storage stability studies demonstrated that the particle size and entrapment efficiency of the MXD-NLCs were not changed during 3 months both at 4°C and room temperature. Moreover, the release of MXD from the NLCs was faster than drug release from SLNs. In vitro skin permeability test demonstrated that MXD-NLCs had a more pronounced permeation and retention profile than MXD-SLNs. Furthermore, no erythema was observed after administration of MXD-NLCs. All these results indicated that the developed MXD-NLCs could be a promising and effective nanocarrier for topical delivery of MXD.


Assuntos
Portadores de Fármacos/química , Lipídeos/química , Minoxidil/química , Nanoestruturas/química , Administração Tópica , Animais , Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Lipídeos/administração & dosagem , Masculino , Minoxidil/administração & dosagem , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanoestruturas/administração & dosagem , Tamanho da Partícula , Permeabilidade , Ratos , Ratos Sprague-Dawley , Pele/metabolismo
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