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1.
Int J Biol Macromol ; 272(Pt 1): 132857, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38834124

RESUMO

Skin damage caused by excessive UV radiation has gradually become one of the most prevalent skin diseases. Collagen has gradually found applications in the treatment of UV-damaged skin; however, their high molecular weight greatly limits their capacity to permeate the skin barrier and repair the damaged skin. Nano collagen has garnered growing attentions in the mimicking of collagen; while the investigation of its skin permeability and wound-healing capability remains vacancies. Herein, we have for the first time created a highly biocompatible and bioactive transdermal nano collagen demonstrating remarkable transdermal capacity and repair efficacy for UV-damaged skin. The transdermal nano collagen exhibited a stable triple-helix structure, effectively promoting the adhesion and proliferation of fibroblasts. Notably, the transdermal nano collagen displayed exceptional penetration capabilities, permeating fibroblast and healthy skin. Combo evaluations revealed that the transdermal nano collagen contributed to recovering the intensity and TEWL values of UV-damaged skin to normal level. Histological analysis further indicated that transdermal nano collagen significantly accelerated the repair of damaged skin by promoting the collagen regeneration and fibroblasts activation. This highly biocompatible and bioactive transdermal nano collagen provides a novel substituted strategy for the transdermal absorption of collagen, indicating great potential applications in cosmetics and dermatology.


Assuntos
Materiais Biocompatíveis , Colágeno , Fibroblastos , Pele , Raios Ultravioleta , Cicatrização , Colágeno/química , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cicatrização/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Administração Cutânea , Camundongos , Proliferação de Células/efeitos dos fármacos
2.
Int J Mol Sci ; 25(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38928256

RESUMO

The construction of peptides to mimic heterogeneous proteins such as type I collagen plays a pivotal role in deciphering their function and pathogenesis. However, progress in the field has been severely hampered by the lack of capability to create stable heterotrimers with desired functional sequences and without the effect of homotrimers. We have herein developed a set of triblock peptides that can assemble into collagen mimetic heterotrimers with desired amino acids and are free from the interference of homotrimers. The triblock peptides comprise a central collagen-like block and two oppositely charged N-/C-terminal blocks, which display inherent incompetency of homotrimer formation. The favorable electrostatic attraction between two paired triblock peptides with complementary terminal charged sequences promptly leads to stable heterotrimers with controlled chain composition. The independence of the collagen-like block from the two terminal blocks endows this system with the adaptability to incorporate desired amino acid sequences while maintaining the heterotrimer structure. The triblock peptides provide a versatile and robust tool to mimic the composition and function of heterotrimer collagen and may have great potential in the design of innovative peptides mimicking heterogeneous proteins.


Assuntos
Colágeno , Peptídeos , Peptídeos/química , Colágeno/química , Multimerização Proteica , Sequência de Aminoácidos , Colágeno Tipo I/química , Eletricidade Estática
3.
BMC Chem ; 18(1): 103, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783370

RESUMO

Fly ash derived from municipal solid waste incinerators (MSWIs) harbors significant quantities of heavy metals with high leaching toxicity, resulting in detrimental environmental effects. Pb2+ in fly ash is the ion most likely to exceed permissible levels. However, chemical stabilization methods demonstrate poor efficacy in stabilizing Pb2+ under acidic conditions. Herein, we have developed a robust acid-resistant chelating polymer (25DTF) for enhanced stabilization of Pb2+ in fly ash. 25DTF was synthesized through the reaction of formaldehyde with 2,5-dithiourea. 25DTF exhibited remarkable chelation efficiency, nearing 100%, for Pb2+ in fly ash. 25DTF demonstrated exceptional chelation efficiency, surpassing 99.9%, when interacting with Pb2+ in fly ash at pH ≤ 7. Even under acidic conditions, 25DTF effectively prevented the secondary dissolution of Pb2+. Additionally, it indicated outstanding Pb2+ chelation efficiency across diverse regions of China. The 25DTF chelating agent shows considerable potential in alleviating metal ion contamination in soil, wastewater, and urban environmental management, thereby fostering advancements in environmental stewardship.

4.
ACS Biomater Sci Eng ; 10(5): 3268-3279, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38659167

RESUMO

The self-assembly of collagen within the human body creates a complex 3D fibrous network, providing structural integrity and mechanical strength to connective tissues. Recombinant collagen plays a pivotal role in the realm of biomimetic natural collagen. However, almost all of the reported recombinant collagens lack the capability of self-assembly, severely hindering their application in tissue engineering and regenerative medicine. Herein, we have for the first time constructed a series of self-assembling tyrosine-rich triple helix recombinant collagens, mimicking the structure and functionality of natural collagen. The recombinant collagen consists of a central triple-helical domain characterized by the (Gly-Xaa-Yaa)n sequence, along with N-terminal and C-terminal domains featuring the GYY sequence. The introduction of GYY has a negligible impact on the stability of the triple-helical structure of recombinant collagen while simultaneously promoting its self-assembly into fibers. In the presence of [Ru(bpy)3]Cl2 and APS as catalysts, tyrosine residues in the recombinant collagen undergo covalent cross-linking, resulting in a hydrogel with exceptional mechanical properties. The recombinant collagen hydrogel exhibits outstanding biocompatibility and bioactivity, significantly enhancing the proliferation, adhesion, migration, and differentiation of HFF-1 cells. This innovative self-assembled triple-helix recombinant collagen demonstrates significant potential in the fields of tissue engineering and medical materials.


Assuntos
Colágeno , Hidrogéis , Proteínas Recombinantes , Tirosina , Tirosina/química , Humanos , Colágeno/química , Hidrogéis/química , Proteínas Recombinantes/química , Proliferação de Células/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Engenharia Tecidual/métodos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Materiais Biocompatíveis/química
5.
J Mater Chem B ; 12(18): 4467-4477, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38629894

RESUMO

Skin aging, a complex and inevitable biological process, results in wrinkles, dermal laxity, and skin cancer, profoundly influencing appearance and overall health. Collagen serves as the fundamental element of the dermal matrix; nevertheless, collagen is susceptible to enzymatic degradation within the body. Crosslinking is employed to enhance the physicochemical properties of collagen. However, conventional crosslinking agents may harbor potential issues such as cytotoxicity and calcification risks, constraining their application in the biomedical field. Therefore, we have for the first time developed a highly biocompatible CE-crosslinked collagen implant with exceptional anti-calcification and collagen regeneration capabilities for aging skin rejuvenation. A novel collagen crosslinking agent (CE) was synthesized through a reaction involving chitosan quaternary ammonium salt with 1,4-butanediol diglycidyl ether. Compared to collagen crosslinked with glutaraldehyde (GA), the CE-crosslinked collagen implant exhibited notable stability and durability. The implant demonstrated excellent injectability and viscosity, resisting displacement after implantation. Additionally, the CE-crosslinked collagen implant displayed superior biocompatibility, effectively promoting the proliferation and adhesion of HFF-1 cells compared with the GA-crosslinked collagen. The CE-crosslinked collagen represented a safer and more biologically active implant material. In vivo experiments further substantiated that the implant significantly facilitated collagen regeneration without inducing calcification. The innovative collagen implant has made substantial strides in enhancing aesthetics and reducing wrinkles, presenting the potential for revolutionary progress in the fields of skin rejuvenation and collagen regeneration.


Assuntos
Materiais Biocompatíveis , Colágeno , Rejuvenescimento , Envelhecimento da Pele , Animais , Humanos , Camundongos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Butileno Glicóis/química , Butileno Glicóis/farmacologia , Proliferação de Células/efeitos dos fármacos , Quitosana/química , Colágeno/química , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/farmacologia , Regeneração/efeitos dos fármacos , Pele/efeitos dos fármacos , Envelhecimento da Pele/efeitos dos fármacos
6.
Int J Biol Macromol ; 266(Pt 2): 131276, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38561117

RESUMO

Skin aging, a complex physiological progression marked by collagen degradation, poses substantial challenges in dermatology. Recombinant collagen emerges as a potential option for skin revitalization, yet its application is constrained by difficulties in forming hydrogels. We have for the first time developed a highly bioactive Tetrakis(hydroxymethyl) phosphonium chloride (THPC)-crosslinked recombinant collagen hydrogel implant for aging skin rejuvenation. THPC demonstrated superior crosslinking efficiency compared to traditional agents such as EDC/NHS and BDDE, achieving complete recombinant collagen crosslinking at minimal concentrations and effectively inducing hydrogel formation. THPC's four reactive hydroxymethyl groups facilitate robust crosslinking with triple helical recombinant collagen, producing hydrogels with enhanced mechanical strength, excellent injectability, increased stability, and greater durability. Moreover, the hydrogel exhibited remarkable biocompatibility and bioactivity, significantly promoting the proliferation, adhesion, and migration of human foreskin fibroblast-1. In photoaged mice skin models, the THPC-crosslinked collagen hydrogel implant notably improved dermal density, skin elasticity, and reduced transepidermal water loss, creating a conducive environment for fibroblast activity and healthy collagen regeneration. Additionally, it elevated superoxide dismutase (SOD) activity and displayed substantial anti-calcification properties. The THPC-crosslinked recombinant collagen hydrogel implant presents an innovative methodology in combating skin aging, offering significant promise in dermatology and tissue engineering.


Assuntos
Colágeno , Hidrogéis , Rejuvenescimento , Envelhecimento da Pele , Hidrogéis/química , Animais , Colágeno/química , Envelhecimento da Pele/efeitos dos fármacos , Camundongos , Humanos , Reagentes de Ligações Cruzadas/química , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Fibroblastos/efeitos dos fármacos , Pele/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Compostos Organofosforados/química , Compostos Organofosforados/farmacologia
7.
Int J Biol Macromol ; 266(Pt 1): 131233, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554907

RESUMO

Full-thickness wounds are severe cutaneous damages with destroyed self-healing function, which need efficient clinical interventions. Inspired by the hierarchical structure of natural skin, we have for the first time developed a biomimetic tri-layered artificial skin (TLAS) comprising silica gel-collagen membrane-collagen porous scaffold for enhanced full-thickness wound healing. The TLAS with the thickness of 3-7 mm displays a hierarchical nanostructure consisting of the top homogeneous silica gel film, the middle compact collagen membrane, and the bottom porous collagen scaffold, exquisitely mimicking the epidermis, basement membrane and dermis of natural skin, respectively. The 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide/N-Hydroxysuccinimide-dehydrothermal (EDC/NHS-DHT) dual-crosslinked collagen composite bilayer, with a crosslinking degree of 79.5 %, displays remarkable biocompatibility, bioactivity, and biosafety with no risk of hemolysis and pyrogen reactions. Notably, the extra collagen membrane layer provides a robust barrier to block the penetration of silica gel into the collagen porous scaffold, leading to the TLAS with enhanced biocompatibility and bioactivity. The full-thickness wound rat model studies have indicated the TLAS significantly facilitates the regeneration of full-thickness defects by accelerating re-epithelization, collagen deposition and migration of skin appendages. The highly biocompatible and bioactive tri-layered artificial skin provides an improved treatment for full-thickness wounds, which has great potential in tissue engineering.


Assuntos
Materiais Biomiméticos , Colágeno , Sílica Gel , Pele Artificial , Alicerces Teciduais , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Colágeno/química , Colágeno/farmacologia , Porosidade , Ratos , Alicerces Teciduais/química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Sílica Gel/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Biomimética/métodos , Humanos , Pele/efeitos dos fármacos , Pele/lesões , Masculino
8.
Biomacromolecules ; 25(4): 2520-2530, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38525550

RESUMO

The construction of collagen mimetic peptides has been a hot topic in tissue engineering due to their attractive advantages, such as virus-free nature and low immunogenicity. However, all of the reported self-assembled peptides rely on the inclusion of risky elements of potential safety concerns or lack the capability of incorporating critical functional motifs. A versatile self-assembly design of pure synthetic peptides that can mimic the collagen structure and function remains an insurmountably challenging target. We have herein created a type of triblock peptide consisting of a central triple helical block and N-terminal/C-terminal blocks with oppositely charged amino acids. Favorable electrostatic interactions between the two terminal blocks have been demonstrated to trigger the triblock peptides to form collagen-like nanofibers with a distinct D-banding pattern. A length of 3 or above charged amino acid pairs as well as the maintenance of the triple helical conformation are required for the self-assembly of triblock peptides. Notably, integrin and discoidin domain receptor (DDR) binding sequences GFOGER and GVMGFO have been well demonstrated as vivid examples of convenient incorporation of functional motifs into the triblock peptides without interfering with their self-assembly. These triblock peptides provide a robust and versatile strategy to create next-generation peptide-based biomaterials that can recapitulate the structure and function of collagen, which have promising applications in the fields of tissue engineering and regenerative medicine.


Assuntos
Colágeno , Peptídeos , Colágeno/química , Peptídeos/química , Integrinas/metabolismo , Materiais Biocompatíveis , Engenharia Tecidual
9.
Patient Prefer Adherence ; 17: 1019-1024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082474

RESUMO

Background: Compared to Western countries, palliative and hospice care services are used less often in Asian countries. While both types have been implemented in mainland China in recent years, their utilization rates have not increased satisfactorily. Moreover, few hospitals in mainland China implement hospice care using the hospice shared care model. Objective: This study investigated a case in which the hospice shared care model was implemented for one patient with advanced colon cancer who had received treatment at a general tertiary hospital in mainland China. Methods: Critical points of care included pain symptom management, nutritional support, application of the SHARE model for disease notification, family meetings to assist medical decision-making, relaxation therapy to relieve depressive symptoms, provisions to address end-of-life wishes, and support for primary caregivers. Results: The patient's basic pain was controlled (Numeric Rating Scale, NRS2-3), and the score of the Depression Screening Scale (PHQ-9) decreased from 15 to 10 after intervention during hospitalization. In the end, the patient died comfortably and peacefully at home. Conclusion: The hospice shared care team helped the patient with her physical and psychological pain, met her end-of-life wishes, and provided support for the families.

10.
Biotechnol Rep (Amst) ; 37: e00778, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36578365

RESUMO

Sunburn is one of the most common skin lesions caused by excessive UV exposure, and its incidence is highly correlated with the risks of skin cancer. A variety of drugs including corticosteroids and NSAIDs have been developed to treat acute sunburn, however, they have raised severe concerns such as poor healing efficacy and long recovery time. We have for the first time extracted non-denatured type I collagen from yak hide, which displays a canonical triple helical structure with melting temperature of 42.7 °C. The highly pure yak collagen type I (YCI) self-assembles to form well-ordered nanofibers with periodic d-bands. YCI is highly biocompatible, and it significantly promotes the proliferation and adhesion of HFF-1 cells. The sunburn healing effects of YCI has been investigated using acute skin injury mouse model. Histological analysis shows that 4 days' treatment of YCI has resulted in the recovery of sunburned mice skin to a healthy state, indicated by pronounced acceleration of epithelization and collagen deposition. The collagen volume fraction as well as the hydroxyproline (Hyp) content of YCI-treated sunburned skin have been found to be greatly increased, confirming the enhanced regeneration of collagen. YCI creams and dressings have also shown superior healing capacity of sunburn by remarkably shortening the recovery time. Notably, the denatured collagen-targeted staining results indicated a large quantity of denatured collagen in sunburned mice, which became substantially reduced after the YCI treatment. FITC-labeled YCI has been further found to penetrate into the dermis of sunburned mice. The highly biocompatible and bioactive non-denatured YCI provides an improved treatment of sunburn, indicating very promising applications of YCI in cosmetics and dermatology.

11.
Nurs Open ; 9(1): 513-518, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655279

RESUMO

AIM: To investigate the characteristics of workplace violence at primary hospitals in Southeast China and identify associated risk factors. DESIGN: A cross-sectional survey design was used for this work. METHODS: We distributed a workplace violence questionnaire among medical staff at primary hospitals in Southeast Zhejiang Province, China. The data were collected between December 2016 and December 2017. We analysed the categorical data by using the chi-square test and expressed it as frequencies. The risk factors were analysed by using multiple logistic regression analysis. RESULTS: Among the 2,560 questionnaires, 1,842 (71.9%) medical staff indicated that they had experienced workplace violence. Verbal assault was the most common type, followed by physical and sexual assault. Furthermore, gender, age, marital status, education, technical position and number of hospital beds' numbers were independent risk factors.


Assuntos
Recursos Humanos de Enfermagem Hospitalar , Violência no Trabalho , Estudos Transversais , Hospitais , Humanos , Prevalência
12.
J Cancer Res Ther ; 16(5): 1151-1156, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33004763

RESUMO

CONTEXT: Percutaneous image-guided thermal ablation has emerged as a valuable therapeutic approach for hepatic malignancies. Magnetic resonance imaging (MRI) has shown potential for great soft-tissue resolution and multiplanar capabilities in arbitrary imaging planes, which are also critical for treatment planning, targeting, and evaluation. AIMS: The aim of this study was to investigate the feasibility, technical success, safety, and follow-up of hepatic malignancies treated with MRI-guided microwave ablation (MWA). MATERIALS AND METHODS: MRI-guided MWA was performed in a closed-bore 1.5 T MR system. T1-weighted imaging was used as a monitoring tool during surgery. T2-weighted imaging was performed to obtain an adequate tumor margin, to calculate the tumor size. Multi-b-value diffusion-weighted imaging (DWI) was performed postprocedurally. Enhanced MRI was performed at 4 weeks, to assess the technical success, and every 3-6 months as a follow-up. RESULTS: Twenty-six patients (38 lesions) were enrolled in the study. A primary efficacy rate of 100% was achieved, and no major complications were observed. Two patient cohorts were identified based on lesion size. Six lesions with incomplete circles on reconstructed DWI appeared immediately postprocedure, and persistent hyperintense signals developed into new lesions over the subsequent 6-12 months. CONCLUSION: MRI-guided ablation is feasible and effective for planning and evaluating MWA in hepatic malignancies. The available clinical data strongly support the advantages of the assessment of tumors through 3D imaging versus routine axial images.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Hepáticas/cirurgia , Micro-Ondas/uso terapêutico , Ablação por Radiofrequência/métodos , Cirurgia Assistida por Computador/métodos , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Estudos Retrospectivos , Resultado do Tratamento
13.
J Mater Chem B ; 7(48): 7676-7682, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31566640

RESUMO

Collagen with a single amino acid substitution is the main cause of a plethora of heritable disorders such as Osteogenesis Imperfecta and Ehlers-Danlos syndrome. Though significant advances have been achieved in the development of protein assays, it remains very challenging to distinguish a protein with a single amino acid mutation from the wild-type protein. A novel fluorescent self-quenching assay has been constructed to detect target collagen peptides with a single amino acid mutation using two probe peptides. The hybridization of the probe peptide and the natural target collagen peptide results in a complete heterotrimer and strong fluorescence, whereas the mixture of the probe peptide and the mutation collagen sequences leads to a partial homotrimer and pronounced fluorescence self-quenching. The extent of fluorescence quenching is dependent on the identity of the residue replacing Gly following the order of Ala < Ser < Arg, while the Gly-Ala mutation causes the mildest fluorescence loss. The probe peptide-based fluorescence self-quenching assay facilitates specific detection of the target collagen sequence with a single Gly mutation at the nM level. The simultaneous utilization of both probe peptides enables efficient discrimination between different mutation peptides. To our knowledge, our work may be the first report of a robust analytical assay that can identify collagen fragments with single amino acid mutation, which will greatly contribute to deciphering the molecular mechanism of Osteogenesis Imperfecta as well as developing novel diagnostic strategies.


Assuntos
Substituição de Aminoácidos , Colágeno/genética , Corantes Fluorescentes , Mutação , Fragmentos de Peptídeos/genética , Sequência de Aminoácidos , Fluorescência , Glicina , Humanos , Osteogênese Imperfeita/diagnóstico , Peptídeos/genética
14.
Chembiochem ; 20(24): 3013-3019, 2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31237990

RESUMO

Osteogenesis imperfecta (OI) is a hereditary bone disorder with various phenotypes ranging from mild multiple fractures to perinatal lethal cases, and it mainly results from the substitution of Gly by a bulkier residue in type I collagen. Triple-helical peptide models of Gly mutations have been widely utilized to decipher the etiology of OI, although these studies are mainly limited to characterizing the peptide features, such as stability and conformation in the solution state. Herein, we have constructed a new series of triple-helical peptides DD(GPO)5 ZPO(GPO)4 DD (Z=Ala, Arg, Asp, Cys, Glu, Ser, and Val) mimicking the most common types of observed OI cases. The inclusion of special terminal aspartic acids enables these collagen mimetic peptides to self-assemble to form nanomaterials upon the trigger of lanthanide ions. We have for the first time systematically evaluated the effect of different OI mutations on the aggregated state of collagen mimetic peptides. We have revealed that the identity of the Gly-substituting residue plays a determinant role in the morphology and secondary structure of the collagen peptide assemblies, showing that bulkier residues tend to result in a disruptive secondary structure and defective morphology, which lead to more severe OI phenotypes. These findings of osteogenesis imperfecta collagen mimetic peptides in the aggregation state provide novel perspectives on the molecular mechanism of osteogenesis imperfecta, and may aid the development of new therapeutic strategies.


Assuntos
Colágeno/metabolismo , Glicina , Osteogênese Imperfeita/metabolismo , Peptidomiméticos/química , Peptidomiméticos/metabolismo , Sequência de Aminoácidos , Modelos Moleculares , Conformação Proteica em alfa-Hélice , Temperatura
15.
Mol Pharm ; 16(2): 846-855, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30592426

RESUMO

Collagen mimetic scaffolds play a pivotal role in regenerative medicine and tissue engineering due to their extraordinary structural and biological features. We have herein, for the first time, reported the construction of luminescent lanthanide-collagen peptide hybrid three-dimensional nanofibrous scaffolds, which well mimic the characteristic architectural structure of native collagen. Three collagen mimetic peptides, composed of repetitive central (GPO)7 sequences and altered terminal amino acids, have been shown to consistently self-assemble to form biocompatible nanofibers under the trigger of a variety of lanthanide ions, which also functionalize the assembled materials with easily tunable photoluminescence. Furthermore, the collagen peptide-lanthanide hybrid scaffolds possess programmable pH-responsive features. The lanthanide ion-mediated assembly of all three collagen peptides are conveniently and reversibly regulated by pH, while their pH-dependent patterns are finely tuned by the identity of terminal amino acids. Using camptothecin and cefoperazone sodium as two model drugs, the drug-loading and releasing efficiency of the collagen peptide-lanthanide scaffolds are nicely modulated by pH, demonstrating the efficacy of these nanofibrous scaffolds as pH-responsive drug carriers. These novel luminescent collagen peptide-lanthanide scaffolds provide a facile system for pH-controlled drug delivery, suggesting promising applications in the development of therapies for many diseases.


Assuntos
Colágeno/química , Peptídeos/química , Sistemas de Liberação de Medicamentos/métodos , Concentração de Íons de Hidrogênio , Nanofibras/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química
16.
RSC Adv ; 8(5): 2404-2409, 2018 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35541475

RESUMO

The development of novel strategies to construct collagen mimetic peptides capable of self-assembling into higher-order structures plays a critical role in the discovery of functional biomaterials. We herein report the construction of a novel type of amphiphile-like peptide conjugating the repetitive triple helical (GPO) m sequences characteristic of collagen with terminal hydrophilic aspartic acids. The amphiphile-like collagen mimic peptides containing a variable length of (Gly-Pro-Hyp) m sequences consistently generate well-ordered nanospherical supramolecular structures. The C-terminal aspartic acids have been revealed to play a determinant role in the appropriate self-assembly of amphiphile-like collagen mimic peptides. Their presence is a prerequisite for self-assembly, and their lengths could modulate the morphology of final assemblies. We have demonstrated for the first time that amphiphile-like collagen mimic peptides with terminal aspartic acids may provide a general and convenient strategy to create well-defined nanostructures in addition to amphiphile-like peptides utilizing ß-sheet or α-helical coiled-coil motifs. The newly developed assembly strategy together with the ubiquitous natural function of collagen may lead to the generation of novel improved biomaterials.

17.
Sci Rep ; 7(1): 10290, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28860629

RESUMO

Biosensors based on the two-dimensional layered nanomaterials transition metal dichalcogenides such as WS2 and MoS2 have shown broad applications, while they largely rely on the utilization of single stranded DNA as probe biomolecules. Herein we have constructed novel WS2- and MoS2- based biosensing platforms using peptides as probe biomolecules. We have revealed for the first time that the WS2 and MoS2 nanosheets display a distinct adsorption for Arg amino acid and particularly, Arg-rich peptdies. We have demonstrated that the WS2 and MoS2 dramatically quench the fluorescence of our constructed Arg-rich probe peptide, while the hybridization of the probe peptide with its target collagen sequence leads to the fluorescence recovery. The WS2-based platform provides a sensitive fluorescence-enhanced assay that is highly specific to the target collagen peptide with little interferences from other proteins. This assay can be applied for quantitative detection of collagen biomarkers in complex biological fluids. The successful development of WS2- and MoS2- based biosensors using non-ssDNA probes opens great opportunities for the construction of novel multifunctional biosensing platforms, which may have great potential in a wide range of biomedical field.


Assuntos
Técnicas Biossensoriais , Dissulfetos , Molibdênio , Nanoestruturas , Tungstênio , Aminoácidos/metabolismo , Colágeno/química , Dissulfetos/química , Molibdênio/química , Nanoestruturas/química , Peptídeos/química , Análise Espectral , Tungstênio/química
18.
Eur Neurol ; 69(6): 336-43, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23549225

RESUMO

Post-stroke depression (PSD) is a common yet severe sequela of stroke, and is often accompanied with somatic symptoms. Duloxetine, a new serotonin-norepinephrine reuptake inhibitor, may help to prevent depression after stroke. 95 ischemic stroke patients without depression were randomly divided into two groups: duloxetine group (n = 47) and control group (n = 48). Patients in the control group received routine ischemic stroke therapy, whereas patients in the duloxetine group received duloxetine (dose range 30-90 mg) for 12 weeks in addition to routine therapy. Follow-up observations lasted for 24 weeks. The Hamilton Depression Scale was used to measure depression, and the National Institute of Stroke Scale, Mini-Mental State Examination, Activities of Daily Living Scale (Chinese version) and Short Form 36 Health Survey Questionnaire were used to assess neurological function, cognitive function, rehabilitation from stroke and quality of life. Results showed that in general, duloxetine spared ischemic stroke patients from both minor and major depression by 16%. In addition, duloxetine helped patients to rehabilitate more rapidly from stroke, and was associated with better cognitive function and quality of life. In conclusion, the prophylactic use of duloxetine not only decreased the incidence of PSD, but also promoted rehabilitation, cognitive function and quality of life.


Assuntos
Antidepressivos/uso terapêutico , Depressão/prevenção & controle , Acidente Vascular Cerebral/psicologia , Tiofenos/uso terapêutico , Idoso , Cloridrato de Duloxetina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Método Simples-Cego , Acidente Vascular Cerebral/complicações
19.
Chin Med J (Engl) ; 125(3): 486-90, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22490408

RESUMO

BACKGROUND: The etiology and pathology of functional constipation (FC) is unclear. Some researches suggest that psychological factors may be related to this common problem. This study aimed to investigate the relationship between attention processing and emotional status in FC patients compared with healthy controls. METHODS: We investigated selective attention and emotional status in patients with FC using the counting Stroop task. Thirty-five FC patients (FCP group) and 24 healthy controls (HCs) underwent an event-related potential (ERP) study while performing the task. Response time, latency and amplitude of P300 were collected and compared between the two groups. The Hamilton Depression Rating Scale (HAMD-17), Hamilton Anxiety Scale (HAMA), Symptom Checklist-90 (SCL-90) and Eysenck Personality Questionnaire (EPQ) were administered prior to the counting Stroop task. RESULTS: Scores for the FCP group differed significantly from those for the HCs on the HAMD-17, HAMA, SCL-90 (Global Severity Index, Positive Symptoms Total, dimensions of somatization, obsessive-compulsive, depression, anxiety, and psychosis), as well as extraversion and neurosis dimensions of the EPQ (P < 0.05). There was no significant difference in response time or accuracy rate between the two groups (P > 0.05). ERP results showed prolonged latency at F4, additionally found enhanced activation at F3, FC1 and T8, and decreased activation at sites FC6 and P7 in the patients with FC. Statistically, significant differences of P300 latency at site F4 (P < 0.05) and P300 amplitude at F3, F4, T8, P7, FC1 and FC6 (P < 0.05) between the patients with FC and the HC were revealed. CONCLUSIONS: The findings suggest that patients with FC are more susceptible to depression and anxiety, as well as somatization, obsessive-compulsive tendencies and other neurotic personality characteristics. Patients may employ psychological defense mechanisms to avoid the pain of depression and anxiety. ERP results imply there may be some brain dysfunction and attention deficits in patients with FC.


Assuntos
Constipação Intestinal/complicações , Constipação Intestinal/fisiopatologia , Adolescente , Adulto , Idoso , Ansiedade/etiologia , Ansiedade/fisiopatologia , Depressão/etiologia , Depressão/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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