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1.
ACS Appl Mater Interfaces ; 14(38): 42812-42826, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36112403

RESUMO

In situ-gel-forming thermoresponsive copolymers have been widely exploited in controlled delivery applications because their critical gel temperature is similar to human body temperature. However, there are limitations to controlling the delivery of biologics from a hydrogel network because of the poor networking and reinforcement between the copolymer networks. This study developed an in situ-forming robust injectable and 3D printable hydrogel network based on cellulose nanocrystals (CNCs) incorporated amphiphilic copolymers, poly(ε-caprolactone-co-lactide)-b-poly(ethylene glycol)-b-poly(ε-caprolactone-co-lactide (PCLA). In addition, the physicochemical and mechanical properties of injectable hydrogels were controlled by physically incorporating CNCs with amphiphilic PCLA copolymers. CNCs played an unprecedented role in physically reinforcing the PCLA copolymers' micelle network via intermicellar bridges. Apart from that, the free-flowing closely packed rod-like CNCs incorporated PCLA micelle networks at low temperature transformed to a stable viscoelastic hydrogel network at physiological temperature. CNC incorporated PCLA copolymer sols effectively coordinated with hydrophobic doxorubicin and water-soluble lysozyme by a combination of hydrophobic and hydrogen bonding interaction and controlled the release of biologics. As shown by the 3D printing results, the biocompatible PCLA hydrogels continuously extruded during printing had good injectability and maintained high shape fidelity after printing without any secondary cross-linking steps. The interlayer bonding between the printed layers was high and formed stable 3D structures up to 10 layers. Subcutaneous injection of free-flowing CNC incorporated PCLA copolymer sols to BALB/c mice formed a hydrogel instantly and showed controlled biodegradation of the hydrogel depot without induction of toxicity at the implantation sites or surrounding tissues. At the same time, the in vivo antitumor effect on the MDA-MB-231 tumor xenograft model demonstrated that DOX-loaded hydrogel formulation significantly inhibited the tumor growth. In summary, the CNC incorporated biodegradable hydrogels developed in this study exhibit a prolonged release with special release kinetics for hydrophobic and hydrophilic biologics.


Assuntos
Produtos Biológicos , Neoplasias da Mama , Nanopartículas , Animais , Neoplasias da Mama/tratamento farmacológico , Celulose , Preparações de Ação Retardada/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Feminino , Humanos , Hidrogéis/química , Camundongos , Micelas , Muramidase , Nanopartículas/uso terapêutico , Poliésteres/química , Polietilenoglicóis/química , Polímeros/química , Impressão Tridimensional , Temperatura , Água
2.
Colloids Surf B Biointerfaces ; 219: 112859, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36162179

RESUMO

Articular cartilage injury is characterized by limited self-repair capacity due to the shortage of blood vessels, lymphatics, and nerves. Hence, this study aims to exploit a classic injectable hydrogel platform that can restore the cartilage defects with minimally invasive surgery, which is similar to the natural extracellular microenvironment, and highly porous network for cell adhesion and proliferation. In this study, an injectable scaffold system comprised of silk fibroin (SF) and hyaluronic acid (HA) was developed to adapt the above requirements. Besides, methylprednisolone (MP) was encapsulated by SF/HA scaffold for alleviating inflammation. The SF/HA hydrogel scaffold was prepared by chemical cross-linking between the lysine residues of SF via Schiff base formation, and pore diameter of the obtained hydrogels was 100.47 ± 32.09 µm. The highly porous nature of hydrogel could further benefit the soft tissue regeneration. Compared with HA-free hydrogels, SF/HA hydrogel showed more controlled release on MP. In ovo experiment of chick embryo chorioallantoic membrane (CAM) demonstrated that SF/HA hydrogels not altered the angiogenesis and formation of blood vessels, thus making it suitable for cartilage regeneration. Furthermore, in vivo gel formation was validated in mice model, suggesting in situ gel formation of SF/HA hydrogels. More importantly, SF/HA hydrogels exhibited the controlled biodegradation. Overall, SF/HA hydrogels provide further insights to the preparation of effective scaffold for tissue regeneration and pave the way to improve the articular cartilage injury treatment.

3.
Tob Use Insights ; 15: 1179173X221098460, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35510034

RESUMO

BACKGROUND: Smoking leads to many smoking-attributable diseases. The promotion of quitting tobacco smoking is urgent as it has significant and immediate health benefits and improves the impacts of other tobacco control strategies. Intention to quit smoking is considered the first step before quitting smoking. METHODOLOGY: This paper used data from Vietnam provincial GATS 2020 on 80,166 participants who were 15-year-old or older. Data were collected from 34 provinces and cities throughout Vietnam and managed using REDCap. RESULTS: Among those who were current smokers, 50.3% (95% CI: 49.1%-51.4%) had the intention to quit smoking. Some predictive factors found to be positively associated with the intention to quit smoking were age (from 45-64), education level, received information about harmful effects or encouragement to quit smoking from media channels (from 6 channels), hearing about the Tobacco Control Law and noticing health warnings on the cigarette package. There was no significant difference in intention to quit smoking between current smokers from urban and rural areas or among different age groups to start smoking. CONCLUSIONS: Interventions or health promotion programs on smoking cessation should be focused on current smokers who have low education levels as they have a higher smoking rate and are less motivated to stop smoking. Received information about harmful effects or encouragement to quit smoking from media channels is also associated with stopping smoking in the future. The importance of health warning pictures on tobacco packages should be maintained and promoted as it has a specific effect on one's intention to stop smoking.

4.
Pharmaceutics ; 14(4)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35456546

RESUMO

Despite the potential of hydrogel-based localized cancer therapies, their efficacy can be limited by cancer recurrence. Therefore, it is of great significance to develop a hydrogel system that can provoke robust and durable immune response in the human body. This study has developed an injectable protein-polymer-based porous hydrogel network composed of lysozyme and poly(ε-caprolactone-co-lactide)-b-poly(ethylene glycol)-b-poly(ε-caprolactone-co-lactide (PCLA) (Lys-PCLA) bioconjugate for the active recruitment dendritic cells (DCs). The Lys-PCLA bioconjugates are prepared using thiol-ene reaction between thiolated lysozyme (Lys-SH) and acrylated PCLA (PCLA-Ac). The free-flowing Lys-PCLA bioconjugate sols at low temperature transformed to immovable gel at the physiological condition and exhibited stability upon dilution with buffers. According to the in vitro toxicity test, the Lys-PCLA bioconjugate and PCLA copolymer were non-toxic to RAW 263.7 cells at higher concentrations (1000 µg/mL). In addition, subcutaneous administration of Lys-PCLA bioconjugate sols formed stable hydrogel depot instantly, which suggested the in situ gel forming ability of the bioconjugate. Moreover, the Lys-PCLA bioconjugate hydrogel depot formed at the interface between subcutaneous tissue and dermis layers allowed the active migration and recruitment of DCs. As suggested by these results, the in-situ forming injectable Lys-PCLA bioconjugate hydrogel depot may serve as an implantable immune niche for the recruitment and modification of DCs.

5.
J Immunol ; 208(6): 1352-1361, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35217585

RESUMO

The major human genes regulating Mycobacterium tuberculosis-induced immune responses and tuberculosis (TB) susceptibility are poorly understood. Although IL-12 and IL-10 are critical for TB pathogenesis, the genetic factors that regulate their expression in humans are unknown. CNBP, REL, and BHLHE40 are master regulators of IL-12 and IL-10 signaling. We hypothesized that common variants in CNBP, REL, and BHLHE40 were associated with IL-12 and IL-10 production from dendritic cells, and that these variants also influence adaptive immune responses to bacillus Calmette-Guérin (BCG) vaccination and TB susceptibility. We characterized the association between common variants in CNBP, REL, and BHLHE40, innate immune responses in dendritic cells and monocyte-derived macrophages, BCG-specific T cell responses, and susceptibility to pediatric and adult TB in human populations. BHLHE40 single-nucleotide polymorphism (SNP) rs4496464 was associated with increased BHLHE40 expression in monocyte-derived macrophages and increased IL-10 from peripheral blood dendritic cells and monocyte-derived macrophages after LPS and TB whole-cell lysate stimulation. SNP BHLHE40 rs11130215, in linkage disequilibrium with rs4496464, was associated with increased BCG-specific IL-2+CD4+ T cell responses and decreased risk for pediatric TB in South Africa. SNPs REL rs842634 and rs842618 were associated with increased IL-12 production from dendritic cells, and SNP REL rs842618 was associated with increased risk for TB meningitis. In summary, we found that genetic variations in REL and BHLHE40 are associated with IL-12 and IL-10 cytokine responses and TB clinical outcomes. Common human genetic regulation of well-defined intermediate cellular traits provides insights into mechanisms of TB pathogenesis.


Assuntos
Mycobacterium bovis , Mycobacterium tuberculosis , Proteínas Proto-Oncogênicas c-rel/genética , Tuberculose , Adulto , Vacina BCG , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Criança , Proteínas de Homeodomínio , Humanos , Interleucina-10/genética , Interleucina-12/genética , Tuberculose/genética
6.
Biomater Sci ; 9(21): 7275-7286, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34609388

RESUMO

Hepatocellular carcinoma is the most common malignancy with a high incidence rate and is the leading cause of cancer-related deaths. Herein, we developed a thermo-responsive hydrogel comprising poly(ε-caprolactone-co-lactide)-b-poly(ethylene glycol)-b-poly(ε-caprolactone-co-lactide (PCLA) that exhibits acidity-accelerated delivery of the tumor-targeting glucuronic acid-bearing doxorubicin (DOX-pH-GA) conjugate into tumor tissues. The PCLA copolymer was post-modified with boronic acid (BA-PCLA) to covalently cross-link with the pH-responsive DOX-pH-GA conjugate. The BA-PCLA copolymer effectively coordinated with the DOX-pH-GA conjugate through the boronate ester formation and showed a lower critical gelation temperature. The DOX conjugated via boronate ester exhibited a sustained release in vitro. Subcutaneous administration of PCLA copolymers formed in situ gels in the subcutaneous layers of Sprague-Dawley rats and degraded after 6 weeks. Similarly, BA-PCLA copolymers coordinated with DOX-pH-GA formed a stable in situ gel in vivo. In vivo imaging studies demonstrated that DOX-pH-GA was released in a sustained manner. The anti-tumor activity of the DOX releasing injectable hydrogel was examined using a HepG2 liver cancer xenograft model. The in vivo antitumor effect demonstrated that the DOX releasing hydrogel depot remarkably suppresses the tumor growth. These results demonstrate that the pH-responsive DOX releasing thermo-responsive hydrogel depot has great potential for application in localized anticancer therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Ésteres , Hidrogéis , Concentração de Íons de Hidrogênio , Neoplasias Hepáticas/tratamento farmacológico , Ratos , Ratos Sprague-Dawley
7.
Biomaterials ; 230: 119599, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31718883

RESUMO

Cancer vaccines that elicit a robust and durable antitumor response show great promise in cancer immunotherapy. Nevertheless, low immunogenicity and weak immune response limit the application of cancer vaccines. To experience next generation cancer vaccines that elicit robust, durable, and anti-tumor T cell response, herein we design injectable smart hydrogels (ISHs) that self-assemble into a cellular microenvironment-like microporous network using a simple hypodermic needle injection, to localize the immune cells and program host cells. ISHs, composed of levodopa- and poly(ε-caprolactone-co-lactide)ester-functionalized hyaluronic acid (HA-PCLA), are loaded with immunomodulatory factor (OVA expressing plasmid, pOVA)-bearing nano-sized polyplexes and granulocyte-macrophage colony-stimulating factor (GM-CSF) as dendritic cell (DC) enhancement factor. Subcutaneous administration of ISHs effectively localized immune cells, and controlled the delivery of immunomodulatory factors to recruit immune cells. The microporous network allowed the recruitment of a substantial number of DCs, which was 6-fold higher than conventional PCLA counterpart. The locally released nano-sized polyplexes effectively internalized to DCs, resulting in the presentation of tumor-specific OVA epitope, and subsequent activation of CD4+ T cells and generation of OVA-specific serum antibody. By the controlled release of nano-sized polyplexes and GM-CSF through a single subcutaneous injection, the ISHs effectively eliminated B16/OVA melanoma tumors in mice. These ISHs can be administered using a minimal invasive technique that could bypass the need for extracorporeal training of cells ex vivo, and provide sustained release of cancer vaccines for immunomodulation. These important findings suggest that ISHs can serve as powerful biomaterials for cancer immunotherapy.


Assuntos
Vacinas Anticâncer , Hidrogéis , Imunidade Humoral , Neoplasias Pulmonares , Animais , Células Dendríticas/imunologia , Humanos , Pulmão , Neoplasias Pulmonares/terapia , Camundongos , Camundongos Endogâmicos C57BL , Microambiente Tumoral
8.
Biomater Sci ; 7(12): 5424-5437, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31638108

RESUMO

Development of implantable material to control the release of chemotherapeutics in the body is a promising approach to control cancer cell proliferation; however, implantation requires surgical intervention. Herein, we propose the in situ formation of injectable biogels (IBGs) for the programmed delivery of potent chemotherapeutic drugs. IBGs are developed via cohesive molecular assembly of a polysaccharide-polymer network comprised of hyaluronic acid-poly(ß-amino urethane). Biocompatible IBGs could be administered subcutaneously through a hypodermic needle in vivo to subsequently assemble into a microporous network. The hyaluronic acid-shielded network mimics the natural extracellular matrix, avoiding rapid degradation of IBGs, with a soft texture and adhesiveness facilitating integration with dermal tissues after subcutaneous implantation. The natural-mimicking architecture confers the IBG network controlled degradation and bioresorbable properties. Subcutaneous administration of IBGs controlled the delivery of a therapeutic agent in a spatio-temporal manner. Therapeutic agents delivered near the tumors in a sustained manner were effectively infiltrated into the thick solid tumors and provide a durable and enhanced anti-tumor response in the B16/OVA melanoma model in vivo. These results indicate that IBGs could be potential medical interventions for the treatment of cancers.


Assuntos
Antineoplásicos/administração & dosagem , Géis/síntese química , Ácido Hialurônico/química , Melanoma/tratamento farmacológico , Poliuretanos/administração & dosagem , Células A549 , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Géis/química , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Injeções Subcutâneas , Células MCF-7 , Poliuretanos/química , Poliuretanos/farmacologia , Ratos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Biomaterials ; 195: 100-110, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30623788

RESUMO

Lymphoid organs, which are populated by dendritic cells (DCs), are highly specialized tissues and provide an ideal microenvironment for T-cell priming. However, intramuscular or subcutaneous delivery of vaccine to DCs, a subset of antigen-presenting cells, has failed to stimulate optimal immune response for effective vaccination and need for adjuvants to induce immune response. To address this issue, we developed an in situ-forming injectable hybrid hydrogel that spontaneously assemble into microporous network upon subcutaneous administration, which provide a cellular niche to host immune cells, including DCs. In situ-forming injectable hybrid hydrogelators, composed of protein-polymer conjugates, formed a hydrogel depot at the close proximity to the dermis, resulting in a rapid migration of immune cells to the hydrogel boundary and infiltration to the microporous network. The biocompatibility of the watery microporous network allows recruitment of DCs without a DC enhancement factor, which was significantly higher than that of traditional hydrogel releasing chemoattractants, granulocyte-macrophage colony-stimulating factor. Owing to the sustained degradation of microporous hydrogel network, DNA vaccine release can be sustained, and the recruitment of DCs and their homing to lymph node can be modulated. Furthermore, immunization of a vaccine encoding amyloid-ß fusion proteinbearing microporous network induced a robust antigen-specific immune response in vivo and strong recall immune response was exhibited due to immunogenic memory. These hybrid hydrogels can be administered in a minimally invasive manner using hypodermic needle, bypassing the need for cytokine or DC enhancement factor and provide niche to host immune cells. These findings highlight the potential of hybrid hydrogels that may serve as a simple, yet multifunctional, platform for DNA vaccine delivery to modulate immune response.


Assuntos
Hidrogéis/química , Animais , Fatores Quimiotáticos/metabolismo , Células Dendríticas/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Linfonodos/metabolismo , Vacinação/métodos , Vacinas de DNA/química
10.
Biomaterials ; 185: 13-24, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30216806

RESUMO

Despite the tremendous potential of DNA-based cancer vaccines, their efficacious delivery to antigen presenting cells to stimulate both humoral and cellular response remains a major challenge. Although electroporation-based transfection has improved performance, an optimal strategy for safe and pain-free vaccination technique remains elusive. Herein, we report a smart DNA vaccine delivery system in which nanoengineered DNA vaccine was laden on microneedles (MNs) assembled with layer-by-layer coating of ultra-pH-responsive OSM-(PEG-PAEU) and immunostimulatory adjuvant poly(I:C), a synthetic double stranded RNA. Transcutaneous application of MN patches onto the mice skin perforate the stratum corneum with minimal cell damage; subsequent disassembly at the immune-cell-rich epidermis/dermis allows the release of adjuvants and DNA vaccines, owing to the ultra-sharp pH-responsive nature of OSM-(PEG-PAEU). The released adjuvant and DNA vaccine can enhance dendritic cell maturation and induce type I interferons, and thereby produce antigen-specific antibody that can achieve the antibody-dependent cell-mediated cytotoxicity (ADCC) and CD8+ T cell to kill cancer cells. Strikingly, transcutaneous application of smart vaccine formulation in mice elicited 3-fold greater frequencies of Anti-OVA IgG1 serum antibody and 3-fold excess of cytotoxic CD8+ T cell than soluble DNA vaccine formulation. As a consequence, the formulation rejected the murine B16/OVA melanoma tumors in C57BL/6 mice through the synergistic activation of antigen-specific ADCC and cytotoxic CD8+ T cells. The maneuvered use of vaccine and adjuvant poly(I:C) in MNs induces humoral and cellular immunity, which provides a promising vaccine technology that shows improved efficacy, compliance, and safety.


Assuntos
Vacinas Anticâncer/administração & dosagem , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/instrumentação , Melanoma Experimental/prevenção & controle , Polímeros/química , Vacinas de DNA/administração & dosagem , Células A549 , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/uso terapêutico , Animais , Vacinas Anticâncer/uso terapêutico , Feminino , Humanos , Concentração de Íons de Hidrogênio , Imunidade Celular , Imunidade Humoral , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microinjeções , Agulhas , Poli I-C/administração & dosagem , Poli I-C/uso terapêutico , Células RAW 264.7 , Adesivo Transdérmico , Vacinas de DNA/uso terapêutico
11.
Biomacromolecules ; 19(8): 3536-3548, 2018 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-30005160

RESUMO

Despite great potential, the delivery of genetic materials into cells or tissues of interest remains challenging owing to their susceptibility to nuclease degradation, lack of permeability to the cell membrane, and short in vivo half-life, which severely restrict their widespread use in therapeutics. To surmount these shortcomings, we developed a bioinspired in situ-forming pH- and temperature-sensitive injectable hydrogel depot that could control the delivery of DNA-bearing polyplexes for versatile biomedical applications. A series of multiblock copolymer, comprised of water-soluble poly(ethylene glycol) (PEG) and pH- and temperature-responsive poly(sulfamethazine ester urethane) (PSMEU), has been synthesized as in situ-forming injectable hydrogelators. The free-flowing PEG-PSMEU copolymer sols at high pH and room temperature (pH 8.5, 23 °C) were transformed to stable gel at the body condition (pH 7.4, 37 °C). Physical and mechanical properties of hydrogels, including their degradation rate and viscosity, are elegantly controlled by varying the composition of urethane ester units. Subcutaneous administration of free-flowing PEG-PSMEU copolymer sols to the dorsal region of Sprague-Dawley rats instantly formed hydrogel depot. The degradation of the hydrogel depot was slow at the beginning and found to be bioresorbable after two months. Cationic protein or DNA-bearing polyplex-loaded PEG-PSMEU copolymer sols formed stable gel and controlled its release over 10 days in vivo. Owing to the presence of urethane linkages, the PEG-PSMEU possesses excellent adhesion strength to wide range of surfaces including glass, plastic, and fresh organs. More importantly, the hydrogels effectively adhered on human skin and peeled easily without eliciting an inflammatory response. Subcutaneous implantation of PEG-PSMEU copolymer sols effectively sealed the ruptured skin, which accelerated the wound healing process as observed by the skin appendage morphogenesis. The bioinspired in situ-forming pH- and temperature-sensitive injectable adhesive hydrogel may provide a promising platform for myriad biomedical applications as controlled delivery vehicle, adhesive, and tissue regeneration.


Assuntos
Adesivos/química , Técnicas de Transferência de Genes , Hidrogéis/química , Cicatrização/efeitos dos fármacos , Adesivos/administração & dosagem , Adesivos/farmacologia , Administração Cutânea , Animais , DNA/administração & dosagem , Feminino , Células HEK293 , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Injeções , Camundongos , Camundongos Endogâmicos BALB C , Polietilenoglicóis/química , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Sulfametazina/análogos & derivados , Temperatura , Uretana/análogos & derivados
12.
J Control Release ; 269: 225-234, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29154976

RESUMO

Successful delivery of a DNA vaccine to antigen-presenting cells and their subsequent stimulation of CD4+ and CD8+ T cell immunity remains an inefficient process. In general, the delivery of prophylactic vaccines is mainly mired by low transfection efficacy, poor immunogenicity, and safety issues from the materials employed. Currently, several strategies have been exploited to improve immunogenicity, but an effective strategy for safe and pain-free delivery of DNA vaccines is complicated. Herein, we report the rapid delivery of polyplex-based DNA vaccines using microneedle arrays coated with a polyelectrolyte multilayer assembly of charge reversal pH-responsive copolymer and heparin. The charge reversal pH-responsive copolymer, composed of oligo(sulfamethazine)-b-poly(ethylene glycol)-b-poly(amino urethane) (OSM-b-PEG-b-PAEU), was used as a triggering layer in the polyelectrolyte multilayer assembly on microneedles. Charge reversal characteristics of this copolymer, that is, the OSM-b-PEG-b-PAEU copolymer exhibit, positive charge at low pH (pH4.03) and becoming negative charge when exposed to physiological pH conditions (pH7.4), allowing the facile assembly and disassembly of polyelectrolyte multilayers. The electrostatic repulsion between heparin and OSM-b-PEG-b-PAEU charge reversal copolymer triggered the release of DNA vaccines. DNA vaccines laden on microneedles are effectively transfected into RAW 264.7 macrophage cells in vitro. Vaccination of BALB/c mice by DNA vaccine-loaded microneedle arrays coated with a polyelectrolyte multilayer generated antigen-specific robust immune responses. These findings provide potential strategy of charge reversal pH-responsive copolymers coated microneedles for DNA vaccine delivery.


Assuntos
Peptídeos beta-Amiloides/genética , Células Apresentadoras de Antígenos/imunologia , Polímeros/administração & dosagem , Sulfametazina/administração & dosagem , Vacinas de DNA/administração & dosagem , Animais , Linhagem Celular , Feminino , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos BALB C , Microinjeções , Agulhas
13.
J Mater Chem B ; 5(34): 7140-7152, 2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32263905

RESUMO

Cisplatin (CDDP) is a well-known anticancer agent, and it has been widely used to treat various solid tumors during clinical cancer therapy. Nevertheless, therapeutic applications of CDDP are hampered by its severe side effects. Although CDDP can be encapsulated into nano-scale drug delivery formulations to improve its physicochemical properties, the lack of stability in the formulation and cancer cell-specific targetability have prompted the exploration of novel vectors for the targeted delivery of CDDP. Here, we introduce CDDP-bearing chondroitin sulfate nanogels (CS-nanogels) that are synthesized through a chelating ligand-metal coordination cross-linking reaction, and then incorporated into pH- and temperature-responsive bioresorbable poly(ethylene glycol)-poly(ß-aminoester urethane) (PEG-PAEU) hydrogels for cancer cell-specific delivery of CDDP. The CS-nanogels released from the hydrogels exhibit a pH-dependent release of CDDP. CDDP was released slowly under physiological conditions (pH 7.4), whereas the release of CDDP was triggered under acidic conditions (pH 5.0). Confocal microscopy images demonstrated that fluorescein-5-thiosemicarbazide-labeled CS-nanogels released from the hydrogels selectively bound to the A549 lung carcinoma cell line through the overexpressing CD44 receptor but not to NIH 3T3 cells. An in vitro cytotoxicity test indicated that CS-nanogels released from the hydrogels effectively inhibited the growth of A549 lung carcinoma cells. Subcutaneous injection of CS-nanogel-loaded PEG-PAEU copolymer sols into the dorsal region of Sprague-Dawley rats spontaneously formed a viscoelastic gel without causing noticeable inflammation at the injection site and was found to be bioresorbable in eight weeks. Overall, the injectable hydrogel-incorporated CS-nanogels were demonstrated to be a useful formulation for the targeted delivery of CDDP.

14.
Steroids ; 104: 246-51, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26476184

RESUMO

Four new polyoxygenated sterol derivatives (1-4) along with the compounds (5-7) previously known from other biological sources were isolated from the gorgonian Menella woodin, collected from the Vietnamese waters. Structures of 1-4 were elucidated by the detailed NMR spectroscopic and mass-spectrometric analyses as well as comparison with those reported in literature data. Compounds 1, 4, and 6 decrease the production of reactive oxygen species (ROS) by the murine macrophages of RAW 264.7 line at induction by endotoxic lipopolysaccharide (LPS) from Escherichia coli.


Assuntos
Antozoários/química , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Esteroides/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Camundongos , Conformação Molecular , Espécies Reativas de Oxigênio/antagonistas & inibidores , Esteroides/química , Esteroides/isolamento & purificação , Relação Estrutura-Atividade
15.
J Nat Prod ; 76(4): 495-502, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23484668

RESUMO

Three new diarylheptanoids, (3S,5R)-3-hydroxy-5-methoxy-1,7-bis(4-hydroxyphenyl)-6E-heptene (1), (3S,5S)-3-hydroxy-5-methoxy-1,7-bis(4-hydroxyphenyl)-6E-heptene (2), and (3S)-3-hydroxy-1,7-bis(4-hydroxyphenyl)-6E-hepten-5-one (3), four new flavonoid glycosides, 3,7,3'-tri-O-methylquercetin-4'-O-ß-d-apiofuranosyl-(1→2)-O-ß-d-glucopyranoside (4), 7,3'-di-O-methylquercetin-4'-O-ß-d-glucopyranosyl-3-O-[6‴-(3-hydroxy-3-methylglutaroyl)]-α-d-glucopyranoside (5), 7,3'-di-O-methylquercetin-4'-O-ß-d-glucopyranosyl-3-O-[(6'''''→5'''')-O-1'''''-(sinap-4-yl)-ß-d-glucopyranosyl-6‴-(3-hydroxy-3-methylglutaroyl)]-α-d-glucopyranoside (6), and (2S)-5-hydroxy-7,3'-dimethoxyflavanone-4'-O-ß-d-apiofuranosyl-(1→5)-O-ß-d-apiofuranosyl-(1→2)-O-ß-d-glucopyranoside (9), and 17 known compounds were isolated from the leaves and twigs of Viscum album. Compounds 1, 4, and 19 significantly inhibited LPS-stimulated production of TNF-α, IL-6, and IL-12p40 with IC50 values ranging from 0.09 ± 0.01 to 8.96 ± 0.45 µM. (+)-Medioresinol (13) showed inhibitory effects on LPS-stimulated production of IL-12p40 with an IC50 value of 2.00 ± 0.15 µM.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Diarileptanoides/isolamento & purificação , Diarileptanoides/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Viscum album/química , Animais , Anti-Inflamatórios/química , Células da Medula Óssea/efeitos dos fármacos , Citocinas/antagonistas & inibidores , Células Dendríticas/efeitos dos fármacos , Diarileptanoides/química , Flavonoides/química , Glicosídeos/química , Concentração Inibidora 50 , Subunidade p40 da Interleucina-12/antagonistas & inibidores , Interleucina-6/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Folhas de Planta/química , Caules de Planta/química , Estereoisomerismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores
16.
Osteoporos Int ; 24(3): 999-1006, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22744715

RESUMO

UNLABELLED: Bone mineral content (BMC) is known to be greater in the dominant arm after the age of 8 years. We studied a group of children and found that BMC sidedness gradually increased up to the age of 6 years and then remained stable into late adolescence. INTRODUCTION: Bone mineral content (BMC) exhibits sidedness in the arms after the age of 8 years, but it is not known whether BMC is greater in the dominant arm from birth or whether lateralization develops in early childhood. To address this, we examined bone mineral status in relation to handedness and age. METHODS: Subjects (N = 158) were children recently initiating glucocorticoids for underlying disease (leukemia 43 %, rheumatic conditions 39 %, nephrotic syndrome 18 %). Handedness was determined by questionnaire and BMC by dual-energy X-ray absorptiometry. RESULTS: Median age was 7.2 years (range, 1.5 to 17.0 years), 49 % was male, and the spine BMD Z-score was -0.9 (SD, 1.3). By linear regression, BMC sidedness in the arms was significantly related to age (r = 0.294, p = 0.0005). Breakpoint analysis revealed two lines with a knot at 6.0 years (95 % CI, 4.5-7.5 years). The formula for the first line was: dominant:nondominant arm BMC ratio = 0.029 × age [in years] + 0.850 (r = 0.323, p = 0.017). The slope of the second line was not different from 0 (p = 0.332), while the slopes for the two lines were significantly different (p = 0.027). CONCLUSIONS: These results show that arm BMC sidedness in this patient group develops up to age 6 years and then remains stable into late adolescence. This temporal profile is consistent with mechanical stimulation of the skeleton in response to asymmetrical muscle use as handedness becomes manifest.


Assuntos
Envelhecimento/fisiologia , Ossos do Braço/fisiologia , Densidade Óssea/fisiologia , Lateralidade Funcional/fisiologia , Absorciometria de Fóton/métodos , Adolescente , Composição Corporal/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Ossos da Perna/fisiologia , Masculino
17.
J Nat Prod ; 74(9): 1908-15, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-21870831

RESUMO

Five new compounds, 16,23,29-trihydroxy-3-oxo-olean-12-en-28-oic acid (1), 4,23,29-trihydroxy-3,4-seco-olean-12-en-3-oate-28-oic acid (2), 3ß,6ß,23-trihydroxyolean-12-en-28-oic acid 28-O-ß-D-glucopyranoside (3), 3-O-[2,3-di-O-acetyl-α-L-arabinopyranosyl]hederagenin 28-O-α-L-rhamnopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranoside (4), and 3-O-[3,4-di-O-acetyl-α-L-arabinopyranosyl]hederagenin 28-O-α-L-rhamnopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranoside (5), as well as 10 known compounds (6-15), were isolated from the stem bark of Kalopanax pictus. Compounds 1-5 and 7-14 inhibited TNFα-induced NF-κB transcriptional activity in HepG2 cells in a dose-dependent manner, with IC50 values ranging from 0.6 to 16.4 µM. Furthermore, the transcriptional inhibitory function of these compounds was confirmed on the basis of decreases in COX-2 and iNOS gene expression in HepG2 cells. The structure-activity relationship of the compounds with respect to anti-inflammatory activity is also discussed.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Kalopanax/química , Saponinas/isolamento & purificação , Saponinas/farmacologia , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Anti-Inflamatórios/química , Sequência de Bases , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/isolamento & purificação , Inibidores de Ciclo-Oxigenase 2/farmacologia , Células Hep G2 , Humanos , Coreia (Geográfico) , Estrutura Molecular , NF-kappa B/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Casca de Planta/química , Saponinas/química , Relação Estrutura-Atividade , Triterpenos/química
19.
Infect Immun ; 78(3): 1364-75, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20028812

RESUMO

Analysis of parasite-host interactions can reveal the intricacies of immunity and identify ways to modulate immunopathological reactions. We assessed the ability of a phosphate-buffered saline-soluble extract of adult Hymenolepis diminuta to suppress macrophage (human THP-1 cell line, murine peritoneal macrophages) activity in vitro and the impact of treating mice with this extract on colitis induced by dinitrobenzene sulfonic acid (DNBS). A high-molecular-mass fraction of adult H. diminuta (HdHMW) or excretory/secretory products reduced macrophage activation: lipopolysaccharide (LPS)-induced interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor alpha (TNF-alpha) and poly(I:C)-induced TNF-alpha and IL-6 were suppressed by HdHMW. The active component in the HdHMW extract was minimally sensitive to boiling and trypsin digestion, whereas the use of sodium metaperiodate, as a general deglycosylation strategy, indicated that the immunosuppressive effect of HdHMW was at least partially dependent on a glycan: treating the HdHMW with neuraminidase and alpha-mannosidase failed to inhibit its blockade of LPS-induced TNF-alpha production by THP-1 macrophages. Mice treated with DNBS developed colitis, as typified by wasting, shortening of the colon, macroscopic and microscopic tissue damage, and an inflammatory infiltrate. Mice cotreated with HdHMW (three intraperitoneal injections) displayed significantly less inflammatory disease, and this was accompanied by reduced TNF-alpha production and increased IL-10 and IL-4 production by mitogen-stimulated spleen cells. However, cotreatment of mice with neutralizing anti-IL-10 antibodies had only a minor impact on the anticolitic effect of the HdHMW. We speculate that purification of the immunosuppressive factor(s) from H. diminuta has the potential to lead to the development of novel immunomodulatory drugs to treat inflammatory disease.


Assuntos
Extratos Celulares/uso terapêutico , Colite/patologia , Hymenolepis diminuta/química , Hymenolepis diminuta/imunologia , Imunossupressores/uso terapêutico , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Animais , Extratos Celulares/química , Extratos Celulares/isolamento & purificação , Linhagem Celular , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/imunologia , Colo/patologia , Humanos , Imunossupressores/química , Imunossupressores/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular
20.
Curr Drug Targets ; 11(1): 48-57, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19839928

RESUMO

Pemetrexed is a multi-targeted anti metabolite that inhibits several key folate-dependent enzymes in the thymidine and purine biosynthetic pathways, including thymidylate synthase. It is currently approved for use in patients with non-small cell lung cancer and malignant mesothelioma. The sporadic and unpredictable occurrence of haematological toxicities of pemetrexed leading to potentially life threatening complications during the early developmental phase, prompted urgent need to identify potential predictive factors for haematological toxicities from pemetrexed. There is a well established association between elevated plasma homocysteine concentration, which is indicative of impaired functional folate status, and increased risk of haematological toxicity from pemetrexed. The decrease in incidence of toxicity after vitamin supplementation confirms the importance of functional folate status as a predictor for haematological toxicity. We review other factors that have a documented impact on haematological toxicity, including pemetrexed schedule, and pharmacokinetic parameters that are indicative of the extent of drug exposure. Further potential factors are explored in this review, such as the genotype of the pemetrexed metabolising enzymes and varying incidences of polymorphism of these genotypes in different ethnic groups that may account for the ethnic differences in neutropenic response to pemetrexed.


Assuntos
Glutamatos/toxicidade , Guanina/análogos & derivados , Doenças Hematológicas/induzido quimicamente , Biomarcadores/sangue , Biomarcadores/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Glutamatos/administração & dosagem , Glutamatos/farmacologia , Guanina/administração & dosagem , Guanina/farmacologia , Guanina/toxicidade , Humanos , Pemetrexede
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