RESUMO
Cisplatin (CDDP) chemoresistance is one of the predominant factors in oral squamous cell carcinoma (OSCC) treatment failure. Uncovering the mechanisms underlying CDDP resistance is of great importance in OSCC therapy. Circular RNAs (circRNAs) are a newly discovered class of noncoding RNAs, which are reported to participate in the progression of various diseases, including cancer. However, the function of circRNAs in CDDP resistance in OSCC remains unclear. Quantitative reverse transcription PCR was used to search for different circRNAs between OSCC cell lines and CDDP-resistant cell lines. The results showed that circ-ILF2 expression was higher in CDDP-resistant OSCC cell lines. The stability of circ-ILF2 was also confirmed using RNase R and actinomycin D assays. Functional experiments, including cytotoxicity, apoptosis and growth rate assays, showed that upregulation of circ-ILF2 contributes to CDDP resistance. Luciferase reporter-gene, RNA pull-down and quantitative real-time PCR (RT-qPCR) assays showed that circ-ILF2 functions as a microRNA sponge for miR-1252. Luciferase reporter assays, RNA pull-down, RT-qPCR and Western blotting showed that miR-1252 directly targeted and regulated the expression of KLF8. Circ-ILF2 plays an important role in CDDP resistance in OSCC. Circ-ILF2 exerts its function through the miR-1252/KLF8 pathway. In addition, tumour-associated macrophages (TAM) play important roles in cancer progressions, our results showed that circ-ILF2 in OSCC cells induced the M2 polarization of macrophages which provided new thoughts on immunotherapy. Our results suggest that circ-ILF2 may represent a potential therapeutic target in CDDP-resistant OSCC.
Assuntos
Cisplatino , Resistencia a Medicamentos Antineoplásicos , RNA Circular , Carcinoma de Células Escamosas de Cabeça e Pescoço , RNA Circular/genética , RNA Circular/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Macrófagos/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/fisiopatologia , Polaridade Celular/genética , HumanosRESUMO
The high prevalence of oral squamous cell carcinoma (OSCC) in South Asia is associated with habitual areca nut chewing. Arecoline, a primary active carcinogen within areca nut extract, is known to promote OSCC pathological development. Dysregulation of N6-methyladenosine (m6A) modification has begun to emerge as a significant contributor to cancer development and progression. However, the biological effects and molecular mechanisms of m6A modification in arecoline-promoted OSCC malignance remain elusive. We reveal that chronic arecoline exposure substantially induces upregulation of fat mass and obesity-associated protein (FTO), MYC, and programmed cell death-ligand 1 (PD-L1) in OSCC cells. Moreover, upregulation of PD-L1 is observed in OSCC cell lines and tissues and is associated with areca nut chewing in OSCC patients. We also demonstrate that arecoline-induced FTO promotes the stability and expression levels of PD-L1 transcripts through mediating m6A modification and MYC activity, respectively. PD-L1 upregulation confers superior cell proliferation, migration, and resistance to T-cell killing to OSCC cells. Blockage of PD-L1 by administration of anti-PD-L1 antibody shrinks tumor size and improves mouse survival by elevating T-cell-mediated tumor cell killing. Therefore, targeting PD-L1 might be a potential therapeutic strategy for treating PD-L1-positive OSCC patients, especially those with habitual areca nut chewing.
Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Animais , Apoptose , Areca/efeitos adversos , Areca/metabolismo , Arecolina/farmacologia , Carcinoma de Células Escamosas/patologia , Imunidade , Ligantes , Camundongos , Neoplasias Bucais/patologia , Obesidade/complicações , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
BACKGROUND: Oral submucosal fibrosis (OSF) is a precancerous condition that closely related to the habit of chewing betel nut. The OSF patients of 3%-19% may develop cancer, and this probability is increasing year by year. Epigenetics modifications have been reported as part of the pathogenesis of OSF. However, in OSF field, the role and mechanism of arecoline-induced activation of transforming growth factor ß (TGF-ß) signaling on N6-methyladenosine (m6A) modification remain unclear. In this study, we investigated the effect and mechanism of arecoline on m6A modification. METHODS: MeRIP-Seq and RNA-seq were performed in arecoline-stimulated cells. Quantitative polymerase chain reaction and western blot were performed to detect the expression of m6A writers and erasers. CCK-8 and flow cytometry analyses were performed to measure the cell viability and apoptosis. RESULTS: m6A level was increased in OSF tissues compared to normal tissues; arecoline promoted the m6A methyltransferase Mettl3 and Mettl14 through TGF-ß. MeRIP-seq and RNA-seq analyses found that MYC was the target gene of Mettl14. In addition, Mettl14 silence reversed the effects of arecoline on cell proliferation and apoptosis in Hacat cells. CONCLUSION: TGF-ß-METTL14-m6A-MYC axis was crucially implicated in arecoline-mediated OSF and may be an effective therapeutic strategy for OSF treatment.
Assuntos
Arecolina , Fibrose Oral Submucosa , Adenosina/análogos & derivados , Adenosina/metabolismo , Arecolina/farmacologia , Humanos , Metiltransferases/genética , Fibrose Oral Submucosa/induzido quimicamente , Fibrose Oral Submucosa/genética , Fator de Crescimento Transformador betaRESUMO
As traditional root canal obturation leads to the loss of the biological activity of the tooth, it is necessary to develop a material that promotes the regeneration of dental tissue. However, this remains a challenging task. Our study aims to construct a mineralized material to support the proliferation and differentiation of dental pulp stem cells (DPSCs), and to explore a new strategy for the treatment of pulp tissue necrosis. Mineralized keratin (M-keratin), defined as keratin that has been mineralized in simulated body fluid, was first harvested to construct the root canal filling material. Characterizations indicated that new substances or components were formed on the surface of keratin particles after mineralization, and the morphology of the keratin was changed. M-keratin promoted the growth, proliferation, and differentiation of DPSCs. After cultivation with M-keratin, DPSCs exhibited more extracellular matrix proteins interacting with the culture interface, the number of these cells increased significantly, and the 3-[4,5-dimethylthiazol-2-yl-]-2,5-diphenyltetrazolium bromide values of cells in the experimental group also increased. Meanwhile, signs that the DPSCs began to differentiate into odontoblasts were observed or detected by alizarin red S staining, ELISA, RNA-Seq, and western blot. We hope that this study will contribute to the development of a new material that promotes the regeneration of dental tissue as well as providing new ideas and strategies for the treatment of dental pulp disease.
Assuntos
Microambiente Celular/efeitos dos fármacos , Queratinas/farmacologia , Odontoblastos/efeitos dos fármacos , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Líquidos Corporais/química , Calcificação Fisiológica/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Implantes Dentários , Polpa Dentária/citologia , Polpa Dentária/fisiologia , Humanos , Queratinas/química , Nanoestruturas/química , Odontoblastos/citologia , Odontoblastos/fisiologia , Ratos , Células-Tronco/efeitos dos fármacos , Células-Tronco/fisiologiaRESUMO
Photodynamic therapy (PDT), combining the laser and photosensitizers to kill tumor cells, has the potential to address many current medical requirements. In this study, magnetic Fe3O4 nanoparticles were first employed as cores and modified with oleic acid (OA) and 3-triethoxysilyl-1-propanamine. Then, the photosensitizers phycocyanin (PC) and hematoporphyrin monomethyl ether (HMME), which might be able to stimulate the cell release of reactive oxygen species after the irradiation of a near-infrared (NIR) laser, were grafted on the surface of such nanoparticles. Our results revealed the high-efficiency inhibition of breast cancer MCF-7 cells growing upon near-infrared irradiation both in vitro and in vivo. Furthermore, it was the synergy between the natural photosensitizers PC and the synthetic photosensitizers HMME that deeply influenced such inhibition compared to the groups that used either of these medicines alone. To utilize the combination of different photosensitive agents, our study thus provides a new strategy for breast cancer treatment.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Hematoporfirinas/uso terapêutico , Nanopartículas de Magnetita/química , Fármacos Fotossensibilizantes/química , Ficocianina/uso terapêutico , Animais , Neoplasias da Mama/patologia , Morte Celular/efeitos dos fármacos , Feminino , Hematoporfirinas/administração & dosagem , Hematoporfirinas/farmacologia , Hematoporfirinas/toxicidade , Humanos , Raios Infravermelhos , Células MCF-7 , Nanopartículas de Magnetita/toxicidade , Camundongos Endogâmicos BALB C , Fotoquimioterapia , Ficocianina/administração & dosagem , Ficocianina/farmacologia , Ficocianina/toxicidadeRESUMO
Parkinson's disease (PD) is second most common neurodegenerative disorder worldwide. Although drugs and surgery can relieve the symptoms of PD, these therapies are incapable of fundamentally treating the disease. For PD patients, over-expression of α-synuclein (SNCA) leads to the death of dopaminergic neurons. This process can be prevented by suppressing SNCA over-expression through RNA interference. Here, we successfully synthesized gold nanoparticles (GNP) composites (CTS@GNP-pDNA-NGF) via the combination of electrostatic adsorption and photochemical immobilization, which could load plasmid DNA (pDNA) and target specific cell types. GNP was transfected into cells via endocytosis to inhibiting the apoptosis of PC12 cells and dopaminergic neurons. Simultaneously, GNP composites are also used in PD models in vivo, and it can successfully cross the blood-brain barrier by contents of GNP in the mice brain. In general, all the works demonstrated that GNP composites have good therapeutic effects for PD models in vitro and in vivo.
Assuntos
Ouro/química , Nanopartículas Metálicas/química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Animais , Humanos , Camundongos , Fator de Crescimento Neural/química , Doença de Parkinson/metabolismo , Plasmídeos/genéticaRESUMO
Polymeric nanoparticles have been widely investigated as insulin delivery systems for oral administration. However, the toxic nature of many artificial polymers hampers their effective application, creating a demand for the further exploration of alternative natural polymers. In addition, ethnobotanical research has reported that over 800 plant species have a hypoglycemic function, some of which are polymers. For the advantages of both areas to be combined, the aim of this work was to choose an organic hypoglycemic polymer and prepare it into an insulin carrier to build a dual-functional oral insulin delivery system. We found that the insulin loading rate, release mode, thermostability, and both in vitro and in vivo absorption and efficacy varied with the different modifications of polygalacturonic acid (PGLA) nanoparticulate backbones. By in vivo pharmaceutical testing and constantly monitoring the symptoms of type 1 diabetic (T1D) rats, we ascertained the hypoglycemic function of the nanoparticles and showed that overall diabetic symptoms were ameliorated after the long-term daily administration of nanoparticles with no significant damage to organ structure or cell viability.
Assuntos
Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Insulina/administração & dosagem , Insulina/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Administração Oral , Animais , Peptídeos Catiônicos Antimicrobianos/química , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Arecoline is known as the main active carcinogen found in areca nut extract that drives the pathological progression of oral squamous cell carcinoma (OSCC). Studies have revealed that dysregulation of RNA N6-methyladenosine (m6A) methyltransferase components is intimately linked to cancer initiation and progression, including oral cancer. METHODS: The arecoline-induced dysregulated methyltransferase-like 3 (METTL3) gene was identified using RNA-seq transcriptome assay. Using in vitro and in vivo models, the biological roles of METTL3 in arecoline-transformed oral cancer were examined. RESULTS: We found that METTL3 was markedly elevated in arecoline-exposed OSCC cell lines and OSCC tissues of areca nut chewers. We identified that hypoxia-inducible factor 1-alpha (HIF-1α) stimulated METTL3 expression at the transcriptional level and further proved that METTL3-MYC-HIF-1α formed a positive autoregulation loop in arecoline-transformed OSCC cells. Subsequently, we manifested that METTL3 depletion profoundly reduced cell proliferation, cell migration, oncogenicity, and cisplatin resistance of arecoline-exposed OSCC cells. CONCLUSIONS: Developing novel strategies to target METTL3 may be a potential way to treat OSCC patients, particularly those with areca nut chewing history and receiving cisplatin treatment.
Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Arecolina/farmacologia , Metiltransferases/genética , Metiltransferases/metabolismo , Cisplatino/farmacologia , RNA , Carcinoma de Células Escamosas/patologia , Carcinogênese/genética , Adenosina/farmacologia , Adenosina/metabolismo , Transformação Celular NeoplásicaRESUMO
Bone diseases such as osteomalacia, osteoporosis, and osteomyelitis are major illnesses that threaten the health of human. This study aimed to provide an idea at the molecular level of material properties determined with UV specific surface approaches. The tert-butyl hydroperoxide (t-BHP) exposure aging model bone mesenchymal stem cells (BMSCs) were reverted by using a poly-hybrid scaffold (PS), which is a carbon nanotube (CNT) coated polycaprolactone (PCL) and polylactic acid (PLA) scaffold, combined with insulin-like growth factor-1 (IGF). Then, the region-specific PS photo-immobilized with different growth factors (GFs) was obtained by interference and diffraction of ultraviolet (UV) light. Additionally, the reverted BMSCs were regionally pattern differentiated into three kinds of cells on the GF immobilized PS (GFs/PS). In vivo, the GFs/PS accelerate bone healing in injured Sprague-Dawley (SD) rats. The data showed that GFs/PS effectively promoted the differentiation of reverted BMSCs in the designated area on 21st day. These results suggest region-specific interface immobilization of GFs concurrently differentiating reverted BMSCs into three different cells in the same scaffold. This method might be considered as a short-time, low cost, and simple operational approach to scaffold modification for tissue regeneration in the future.
Assuntos
Células da Medula Óssea/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Células Imobilizadas/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Alicerces Teciduais , Raios Ultravioleta , Animais , Células da Medula Óssea/fisiologia , Células da Medula Óssea/efeitos da radiação , Regeneração Óssea/fisiologia , Regeneração Óssea/efeitos da radiação , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Diferenciação Celular/efeitos da radiação , Células Cultivadas , Células Imobilizadas/fisiologia , Células Imobilizadas/efeitos da radiação , Feminino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Células-Tronco Mesenquimais/efeitos da radiação , Ratos , Ratos Sprague-DawleyRESUMO
The use of bone tissue engineering scaffolds has become a promising potential treatment for bone defects as they expedite bone healing. A carbon nanotube-hydroxyapatite (CNT-HA) composite can accelerate the growth of cells. However, the molecular organized arrangement of organic and inorganic components is one of the most important biochemical phenomena in the formation of bones. This study aimed to prepare ordered CNT-HA scaffolds by applying agarose gel electrophoresis to imitate a biomimetic parallel pattern of collagens and hydroxyapatite hydrogel scaffolds (AG-Col-o-CNT). Significant improvements were presented in the mechanical properties of the scaffolds and cell growth in vitro or in vivo. The results showed that the AG-Col-o-CNT scaffolds accelerated the proliferation and differentiation of bone mesenchymal stem cell lines. In addition, the bone defects were repaired when the scaffolds were transplanted after 28 and 56 days in vivo. The superior performance of the ordered AG-Col-o-CNT scaffolds indicates that they have an enormous potential for bone tissue engineering.
Assuntos
Materiais Biomiméticos/química , Durapatita/química , Hidrogéis/química , Nanotubos de Carbono/química , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Materiais Biomiméticos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Durapatita/farmacologia , Hidrogéis/farmacologia , Teste de Materiais , Células-Tronco Mesenquimais/efeitos dos fármacos , RatosRESUMO
Lung is one of important organs and lung diseases seriously affect the health of human beings. In this study, chitosan and gelatin as natural biological macromolecules raw material for the synthesis of ordered colloidal crystal scaffolds (CCS), Fe3O4 magnetic nanoparticles (MNPs) were used as pore-making for the first time. The pore-making agent were added into the hydrogels to synthesis the ordered (magnetic field) and disordered (no magnetic field) CCS. Collagen and basic fibroblast growth factor (bFGF) modified on the surface of CCS. Then mouse lung epithelial cells (TC-1) and normal human bronchial epithelial cells (Beas-2B) were cultured on the scaffold, obviously induced cell proliferation. Various physical and chemical characteristics indicate that the preparation of scaffolds and modified growth factors can greatly promote the proliferation of these two cells. In addition, the scafolld was implanted into the SD rat in vivo, and routine blood tests showed that the stent had a small inflammatory response to the rat. This may be one of the effective strategies for the future treatment of lung injury repair.
Assuntos
Coloides/química , Células Epiteliais/citologia , Pulmão/citologia , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis , Brônquios/citologia , Proliferação de Células , Células Cultivadas , Quitosana/química , Colágeno/química , Cristalização , Feminino , Gelatina/química , Humanos , Inflamação , Teste de Materiais , Camundongos , Nanopartículas/química , Porosidade , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície , Temperatura , Engenharia Tecidual/métodosRESUMO
A realistic control of cell cycle arrest is an attractive goal for the development of new effective anti-cancer drugs. Any clinical application of an effective anti-cancer drug necessarily relies on the understanding of cellular interaction mechanisms. In the present study, we prepared a co-immobilized TNF-α plus IFN-γ biomaterial, which showed a significant inhibition effect on cervical cancer cell growth, as demonstrated by a series of structural and cellular characterizations. We found that co-immobilized TNF-α plus IFN-α induced a long-term G1 phase cell cycle arrest in HeLa, SiHa, and CaSki cells, respectively. More surprisingly, the expression level of the p27 protein decreased, even when p27 mRNA was highly expressed. In addition, gene-chip results and microarray analysis showed that p57 may be downstream from p27, which acts as a direct regulator of the long-term G1 cell cycle arrest in these cells, leaving no escape for cervical cancer cells. Finally, we also investigated the anti-tumor mechanism of co-immobilized TNF-α plus IFN-γin vivo, using a nude mice animal model. To sum up, our findings suggested that the co-immobilized TNF-α plus IFN-γ can induce a long-term cell cycle arrest in cancer, thus serving as a very efficient tool for treating cervical cancer.
RESUMO
Oral drug delivery has attracted substantial attention due to its advantages over other administration routes. Bacillus spores, as oral probiotic agents, are applied widely. In this paper, a novel Bacillus spore-based oral colon targeted carrier loading curcumin was developed for colon cancer treatment. Curcumin was linked covalently with the outer coat of Bacillus spore and folate, respectively (SPORE-CUR-FA). Bacillus spores are capable of delivering drugs to the colon area through gastric barrier, taking the advantage of its tolerance to the harsh conditions and disintegration of the outer coat of spores after germination in the colon. The drug release in vitro and in vivo of SPORE-CUR-FA was investigated. Results showed that SPORE-CUR-FA had the characteristics of colon-targeted drug release. Pharmacokinetic studies confirmed that Bacillus spore-based carriers could efficiently improve the oral bioavailability of curcumin. In vitro and in vivo anti-tumor studies showed that SPORE-CUR-FA had substantial ability for inhibiting colon cancer cells. These findings suggest that this Bacillus spore-based oral drug delivery system has a great potential for the treatment of colon cancer.
Assuntos
Antineoplásicos/administração & dosagem , Bacillus coagulans , Neoplasias do Colo/tratamento farmacológico , Curcumina/administração & dosagem , Portadores de Fármacos/administração & dosagem , Ácido Fólico/administração & dosagem , Esporos Bacterianos , Administração Oral , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Curcumina/química , Curcumina/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Ácido Fólico/química , Ácido Fólico/farmacocinética , Células HT29 , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Ratos Sprague-DawleyRESUMO
Cordycepin has been successfully used as a natural anti-cancer drug, but it is rapidly metabolized in vivo. Nanoencapsulation is thus a promising method to improve its bioavailability. In this study, we adopted a green synthesis process to develop novel self-assembling phycocyanin-dextran-cordycepin (Phy-Dex-Cord) micelles for efficient cordycepin encapsulation and delivery. We first used the Maillard reaction method to graft dextran onto phycocyanin, forming a phycocyanin-dextran complex. Through the self-assembly of the cordycepin parcel to the phycocyanin-dextran complex, the micelles were formed. Their physical and chemical properties and characterization results showed that Phy-Dex-Cord micelles have a spherical shape and consistent size distribution of about 60 nm. In addition, anti-cancer activities in vitro and in vivo revealed that the Phy-Dex-Cord micelles have a comparable or even stronger inhibitory effect against C6 cells than do free cordycepin and free phycocyanin and no side effects.
RESUMO
Lewy bodies are considered as the main pathological characteristics of Parkinson's disease (PD). The major component of Lewy bodies is α-synuclein (α-syn). The use of gene therapy that targeting and effectively interfere with the expression of α-syn in neurons has received tremendous attention. In this study, we used magnetic Fe3O4 nanoparticles coated with oleic acid molecules as a nano-carrier. N-isopropylacrylamide derivative (NIPAm-AA) was photo-immobilized onto the oleic acid molecules, and shRNA (short hairpin RNA) was absorbed. The same method was used to absorb nerve growth factor (NGF) to NIPAm-AA to specifically promote neuronal uptake via NGF receptor-mediated endocytosis. Additionally, shRNA plasmid could be released into neurons because of the temperature and pH sensitivity of NIPAm-AA interference with α-syn synthesis. We investigated apoptosis in neurons with abrogated α-syn expression in vitro and in vivo. The results demonstrated that multifunctional superparamagnetic nanoparticles carrying shRNA for α-syn could provide effective repair in a PD model.
Assuntos
Produtos Biológicos/administração & dosagem , Terapia Genética/métodos , Nanopartículas de Magnetita/administração & dosagem , Doença de Parkinson/terapia , Plasmídeos/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , alfa-Sinucleína/antagonistas & inibidores , Acrilamidas/administração & dosagem , Animais , Modelos Animais de Doenças , Portadores de Fármacos/administração & dosagem , Endocitose , Masculino , Camundongos Endogâmicos C57BL , Fator de Crescimento Neural/administração & dosagem , Neurônios/fisiologia , RNA Interferente Pequeno/genética , alfa-Sinucleína/genéticaRESUMO
The destruction of PVC cables by termites is a continuing and long-standing problem, which can lead to power leakage and power cut. Given the environmental demerits of insecticide overuse, alternative methods of addressing this problem are a highly desirable goal. In this study, we used photo-immobilization to develop a chitosan carrier system to help bifenthrin immobilize on the surface of the PVC substrate. The immobilization was analyzed using nuclear magnetic resonance (NMR), UV absorption, reverse-phase high-performance liquid chromatography (RP-HPLC), Raman absorption spectroscopy, and thermal gravimetric analysis (TGA). The surface structure and biological activity of the embedded and immobilized bifenthrin were examined using scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photon-electron spectroscopy (XPS). Its efficacy was assessed in pest experiments. The results indicate a successful embedding and immobilization of bifenthrin. Furthermore, the chemical bonding network between AzPhchitosan, bifenthrin, and PVC is stable, guaranteeing no environmental release of bifenthrin, and also providing more efficacious protection against termites. The evidence suggests that this photo-immobilization of bifenthrin-embedded chitosan on the surface of PVC substrates is a novel and environmentally friendly technique for termite control. This paper also reports a modification of chitosan with respect to its novel application in environmental protection.
Assuntos
Azidas/química , Quitosana/química , Reagentes de Ligações Cruzadas/química , Inseticidas/química , Cloreto de Polivinila/química , Piretrinas/química , Animais , Equipamentos e Provisões Elétricas , Controle de Insetos/métodos , Isópteros , Processos Fotoquímicos , Raios UltravioletaRESUMO
We developed a biomaterial by photo-immobilizing interferon-α (IFN-α) on the surface of latex condom films for the prevention and treatment of cervicitis, cervical cancers and diseases caused by cervical virus. The IFN-α modification by photoactive N-(4-azidobenzoyloxy) succinimide was characterized on a nano-scale by spectroscopy analysis and micro morphology. The anti-bacterial, anti-cancer, and anti-viral effects of the modified bioactive latex films were evaluated by antibacterial susceptibility testing, Gram staining, flow cytometry, immunofluorescence, and Western blotting. Our results showed that the photo-immobilized IFN-α latex films effectively inhibited the growth of both Neisseria gonorrhoeae and human cervical cancer HeLa cells. Moreover, the expression of anti-viral proteins, including P56, MxA, and 2', 5'-OAS, in the human cervical epithelial cell line NC104 was significantly increased by photo-immobilized IFN-α latex films. Taken together, these results suggest that photo-immobilized IFN-α latex films may have therapeutic effects against cervicitis, cervical cancers, and cervical virus.
Assuntos
Interferon-alfa/química , Membranas Artificiais , Proliferação de Células/efeitos dos fármacos , Células HeLa , Humanos , Interferon-alfa/farmacologia , Látex/química , Neisseria gonorrhoeae/efeitos dos fármacosRESUMO
Aiming at the cells' differentiation phenomenon and senescence problem in liver tissue engineering, this work is designed to synthesize three different chargeable polymers (polypropylene acid (PAAc), polyethylene glycol (PEG), and polypropylene amine (PAAm)) coimmobilized by the insulin-like growth factor 1 (IGF-1) and tumor necrosis factor-α (TNF-α). We explore the hepatocyte differentiation effect and the antisenecence effect of PSt-PAAm-IGF-1/TNF-α biomaterial which was selected from the three different chargeable polymers in bone marrow mesenchymal stem cells (BMSCs). Our work will establish a model for studying the biochemical molecular regulation mechanism and signal transduction pathway of cell senescence in liver tissue engineering, which provide a molecular basis for developing biomaterials for liver tissue engineering.
RESUMO
Synthesis of artificial and functional structures for bone tissue engineering has been well recognized but the associated cell senescence issue remains much less concerned so far. In this work, surface-modified polycaprolactone-polylactic acid scaffolds using self-assembled heterojunction carbon nanotubes (sh-CNTs) combined with insulin-like growth factor-1 are synthesized and a series of structural and biological characterizations are carried out, with particular attention to cell senescence mechanism. It is revealed that the modified scaffolds can up-regulate the expressions of alkaline phosphates and bone morphogenetic proteins while down-regulate the expressions of senescence-related proteins in mesenchymal stem cells, demonstrating the highly preferred anti-senescence functionality of the sh-CNTs modified scaffolds in bone tissue engineering. Furthermore, it is also found that with sh-CNTs, scaffolds can accelerate bone healing with extremely low toxicity in vivo.