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1.
Proc Natl Acad Sci U S A ; 118(42)2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34654746

RESUMO

In nature, microorganisms could sense the intensity of the incident visible light and exhibit bidirectional (positive or negative) phototaxis. However, it is still challenging to achieve the similar biomimetic phototaxis for the artificial micro/nanomotor (MNM) counterparts with the size from a few nanometers to a few micrometers. In this work, we report a fuel-free carbon nitride (C3N4)/polypyrrole nanoparticle (PPyNP)-based smart MNM operating in water, whose behavior resembles that of the phototactic microorganism. The MNM moves toward the visible light source under low illumination and away from it under high irradiation, which relies on the competitive interplay between the light-induced self-diffusiophoresis and self-thermophoresis mechanisms concurrently integrated into the MNM. Interestingly, the competition between these two mechanisms leads to a collective bidirectional phototaxis of an ensemble of MNMs under uniform illuminations and a spinning schooling behavior under a nonuniform light, both of which can be finely controllable by visible light energy. Our results provide important insights into the design of the artificial counterpart of the phototactic microorganism with sophisticated motion behaviors for diverse applications.


Assuntos
Luz , Movimento (Física) , Fototaxia , Biomimética , Polímeros/metabolismo , Pirróis/metabolismo
2.
BMC Oral Health ; 24(1): 461, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627719

RESUMO

BACKGROUND: It is uncertain if mean platelet volume and periodontitis are related. The objective of this study was to examine the association between levels of mean platelet volume and moderate/severe periodontitis in adult persons who inhabit the U.S. METHODS: We screened 6,809 people from the National Health and Nutrition Examination Survey (NHANES 2009-2012). Mean platelet volume was measured in the Mobile Examination Centers (MECs) using the Beckman Coulter analyzer. The category of periodontitis was defined by the CDC/AAP using clinical periodontal parameters. Multiple logistic regression models were employed to examine the distribution for covariate differences across the various independent groups. Four models were employed to examine the relationship between mean platelet volume level and periodontitis. Smoothed curve fitting was utilized to confirm the linearity of the relationships. To determine the impact of factors on the connection between MPV and periodontitis, subgroup analysis and interaction testing were utilized. RESULTS: Results from the multiple logistic regression analysis indicate a significant association between moderate/severe periodontitis and the mean platelet level, even after considering any potential confounding variables (OR = 1.090, 95% CI: 1.019-1.166, P-value = 0.01211). Additionally, those in the upper tertile of mean platelet volume levels had a 21.6% higher probability of developing periodontitis when compared with those in the least tertile of mean platelet levels (OR = 1.216, 95% CI:1.052-1.406, P-value = 0.00816). Moreover, it showed a positive correlation between mean platelet volume (MPV) and moderate/severe periodontitis. Subgroup analyses indicated a positive association between the level of mean platelet volume and moderate/severe periodontitis among individuals who were under 60 years of age, had low income, were obese, never smoked, were heavy drinkers, had hypertension, and had no cardiovascular disease (p < 0.05). However, none of the subgroups exhibited significant interactions (p for interaction > 0.05). CONCLUSION: A correlation has been found between mean platelet volume levels and periodontal disease in individuals residing in the United States.


Assuntos
Volume Plaquetário Médio , Periodontite , Adulto , Humanos , Estados Unidos , Estudos Transversais , Inquéritos Nutricionais , Plaquetas
3.
Macromol Rapid Commun ; 44(4): e2200694, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36412066

RESUMO

Poly(malic acid) (PMLA) is a water-soluble, biodegradable, biocompatible, and nontoxic polyester in the poly(hydroxyalkanoate) (PHA) family. it features various applications in pharmaceutical field. Herein, NaCo(CO)4 and pyridine derivatives are employed for direct carbonylative polymerization of benzyl glycidate (BG) for poly(ß-malic acid) production. Further investigation on reaction mechanism reveals that this polymerization undergoes a direct chain growth, rather than a sequential process involving ß-lactone intermediate. The low cost and facile preparation of epoxide substrate render this methodology extremely appealing that avoids the rather tedious procedures for ß-malolactonate synthesis required toward ring opening polymerization. This study also represents an alternative strategy over traditional methods for poly(ß-malic acid) production using step growth polycondensation of malic acid.


Assuntos
Poliésteres , Polímeros , Polimerização
4.
Biomacromolecules ; 23(11): 4825-4833, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36301049

RESUMO

Mesenchymal stem cell-derived exosomes (MSC-Exos) are emerging as a promising platform for treating various intractable diseases and organ injuries. Monitoring their migration, homing, and therapeutic capability in vivo is essential to develop exosome-based theranostics. Here, we designed fluorescent semiconductor polymer dots (Pdots) in the second near-infrared window (NIR-II) for bright labeling and tracking of MSC-Exos. Glucose-coated Pdots (Pdots-Glu) were able to label MSC-Exos without changing their biological properties. The NIR-II fluorescent Pdots allow for high labeling brightness and long-term in vivo tracking of MSC-Exos. We investigated the biodistributions and therapeutic functions of these labeled MSC-Exos in liver-resected mice. In vivo and ex vivo imaging demonstrated that the Pdot-labeled MSC-Exos injected via the tail vein mainly accumulated in the residual liver tissue. In terms of the therapeutic effect, MSC-Exos may accelerate postoperative liver function recovery by inhibiting inflammatory responses, promoting cell proliferation, and resisting apoptosis. Our results indicated that MSC-Exos therapeutic systems hold promising applications in liver regenerative medicine.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Camundongos , Animais , Polímeros , Fígado , Proliferação de Células/fisiologia
5.
Nano Lett ; 21(1): 798-805, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33346668

RESUMO

The concept that systemically administered nanoparticles are highly accumulated into the liver, spleen and kidney is a central paradigm in the field of nanomedicine. Here, we report that bone is an important organ for retention of small polymer nanoparticles using in vivo fluorescence imaging in the second near-infrared (NIR-II) window. We prepared different sized polymer nanoparticles with both visible and NIR-II fluorescence. NIR-II imaging reveals that the behavior of nanoparticle distribution in bone was largely dependent on the particle size. Small polymer nanoparticles of ∼15 nm diameter showed fast accumulation and long-term retention in bone, while the nanoparticles larger than ∼25 nm were dominantly distributed in liver. Confocal microscopy of bone sections indicated that the nanoparticles were largely distributed in the endothelial cells of sinusoidal vessels in bone marrow. The study provides promising opportunities for bone imaging and treatment of bone-related disease.


Assuntos
Nanopartículas , Polímeros , Medula Óssea/diagnóstico por imagem , Células Endoteliais , Imagem Óptica
6.
Angew Chem Int Ed Engl ; 59(47): 21049-21057, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-32767727

RESUMO

Here, we describe a fluorination strategy for semiconducting polymers for the development of highly bright second near-infrared region (NIR-II) probes. Tetrafluorination yielded a fluorescence QY of 3.2 % for the polymer dots (Pdots), over a 3-fold enhancement compared to non-fluorinated counterparts. The fluorescence enhancement was attributable to a nanoscale fluorous effect in the Pdots that maintained the molecular planarity and minimized the structure distortion between the excited state and ground state, thus reducing the nonradiative relaxations. By performing through-skull and through-scalp imaging of the brain vasculature of live mice, we quantitatively analyzed the vascular morphology of transgenic brain tumors in terms of the vessel lengths, vessel branches, and vessel symmetry, which showed statistically significant differences from the wild type animals. The bright NIR-II Pdots obtained through fluorination chemistry provide insightful information for precise diagnosis of the malignancy of the brain tumor.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Fluorescência , Corantes Fluorescentes/química , Imagem Óptica , Polímeros/química , Pontos Quânticos/química , Animais , Halogenação , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Tamanho da Partícula , Semicondutores , Propriedades de Superfície
7.
Eur J Orthod ; 40(3): 273-280, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29036480

RESUMO

Objective: To investigate effects of mandible advanced device (MAD) therapy for obstructive sleep apnoea-hypopnea syndrome (OSAHS) on the neuron apoptosis and acetylcholine esterase activity in frontal cortex. Materials and methods: Thirty male New Zealand white rabbits were randomly divided into three groups (n = 10 in each group): group OSAHS, group MAD, and control group. Hydrophilic polyacrylamide gel was injected into soft palate of the animals to induce OSAHS in group OSAHS and group MAD. The group MAD animals wore MAD to relief the obstructiveness. The control group was not given any treatment. Computed tomography (CT) examination of the upper airway and polysomnography (PSG) recordings were performed in supine position. All rabbits were induced to sleep in a supine position for 4 to 6 hours every day and were observed for consecutive 8 weeks. The frontal cortices of three groups were dissected and the neuron apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and flow cytometry. Acetylcholine esterase (AchE) activity in the frontal cortex was measured by spectrophotometry. Results: The group OSAHS exhibited high neuron apoptosis rate and low AchE activity than those of group MAD and control group. The blood oxygen saturation was negatively correlated with neuronal apoptosis rate and positively correlated with AchE activity. Applying MAD in OSAHS animals significantly improve the neuronal damage and function deficits by apnoea-hypoxia caused by narrowed upper airway. Conclusion: This study provided evidence that MAD therapy for OSAHS can significantly decrease neuronal apoptosis and increase AchE activity in the frontal cortex.


Assuntos
Lobo Frontal/patologia , Avanço Mandibular/instrumentação , Neurônios/patologia , Apneia Obstrutiva do Sono/terapia , Acetilcolinesterase/metabolismo , Animais , Apoptose , Modelos Animais de Doenças , Lobo Frontal/enzimologia , Masculino , Mandíbula/patologia , Palato Mole , Polissonografia/métodos , Coelhos , Distribuição Aleatória , Apneia Obstrutiva do Sono/diagnóstico por imagem , Apneia Obstrutiva do Sono/enzimologia , Apneia Obstrutiva do Sono/patologia , Síndrome , Tomografia Computadorizada por Raios X/métodos
8.
Biomacromolecules ; 17(10): 3115-3126, 2016 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-27599254

RESUMO

Michael addition polymerizations of amines and acrylic monomers are versatile approaches to biomaterials for various applications. A combinatorial library of poly(ß-amino ester)s and diverse poly(amido amine)s from diamines and diacrylates or bis(acrylamide)s have been reported, respectively. Furthermore, novel linear and hyperbranched polymers from Michael addition polymerizations of trifunctional amines and acrylic monomers significantly enrich this category of biomaterials. In this Review, we focus on the biomaterials from Michael addition polymerizations of trifunctional amines and acrylic monomers. First we discuss how the polymerization mechanisms, which are determined by the reactivity sequence of the three types of amines of trifunctional amines, i.e., secondary (2°) amines (original), primary (1°) amines, and 2° amines (formed), are affected by the chemistry of monomers, reaction temperature, and solvent. Then we update how to design and synthesize linear and hyperbranched polymers based on the understanding of polymerization mechanisms. Linear polymers containing 2° amines in the backbones can be obtained from polymerizations of diacrylates or bis(acrylamide)s with equimolar trifunctional amine, and several approaches, e.g., 2A2+BB'B″, A3+2BB'B', A2+BB'B″, to hyperbranched polymers are developed. Further through molecular design of monomers, conjugation of functional species to 2° amines in the backbones of linear polymers and the abundant terminal groups of hyperbranched polymers, the amphiphilicity of polymers can be adjusted, and additional stimuli, e.g., thermal, redox, reactive oxidation species (ROS), and light, responses can be integrated with the intrinsic pH response. Finally we discuss the applications of the polymers for gene/drug delivery and bioimaging through exploring their self-assemblies in various motifs, e.g., micelles, polyplexes particles/nanorings and hydrogels. Redox-responsive hyperbranched polymers can display 300 times higher in vitro gene transfection efficiency and provide a higher in vivo siRNA efficacy than PEI. Also redox-responsive micelle carriers can improve the efficacy of anticancer drug and the bioimaging contrast. Further molecular design and optimization of this category of polymers together with in vivo studies should provide safe and efficient biomaterials for clinical applications.


Assuntos
Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Poliaminas/química , Materiais Biocompatíveis/uso terapêutico , DNA/química , Terapia Genética , Humanos , Micelas , Poliaminas/uso terapêutico , Polimerização , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Transfecção
9.
Eur J Orthod ; 37(3): 284-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25246606

RESUMO

OBJECTIVE: The aim of the study is to establish a stable animal model of obstructive sleep apnoea-hypopnea syndrome (OSAHS) and assess the effectiveness of a mandibular advancement device (MAD). MATERIALS AND METHODS: Eighteen 6-month-old male New Zealand white rabbits were randomized into three groups according to intervention: Group OSAHS, Group MAD, and a control group (n = 6 for each group). Rabbits in Group OSAHS and Group MAD were established as OSAHS model by injection, at a dose of 2 ml hydrophilic polyacrylamide gel, in the submucous muscular layer of the soft palate. Computed tomography (CT) and polysomnography (PSG) showed that OSAHS was developed successfully, the rabbits in Group MAD were fitted with the MAD and CT of the upper airway and PSG evaluated its effectiveness. Histological observation of the injection sites was conducted. RESULTS: CT scans showed the reduced sagittal space and cross-sectional areas of retropalatal upper airway in Group OSAHS were corrected by MAD (upper airway space in Group MAD was similar to that in the control group). The rabbits in Group OSAHS developed obvious sleep apnoea and hypopnea in supine position, with increased apnoea-hypopnea index and decreased oxygen saturation (SaO2). These were significantly improved by MAD and apnoea and hypopnea were not observed. Histology of the soft palate showed that the injected gel was entirely surrounded with connective tissues. CONCLUSION: We primarily developed an OSAHS and MAD therapy animal model with narrow oropharynx in upper airway which could be further available for OSAHS analysis.


Assuntos
Modelos Animais de Doenças , Avanço Mandibular/instrumentação , Desenho de Aparelho Ortodôntico , Apneia Obstrutiva do Sono/terapia , Resinas Acrílicas/administração & dosagem , Anatomia Transversal/métodos , Animais , Cefalometria/métodos , Injeções , Masculino , Orofaringe/diagnóstico por imagem , Oxigênio/sangue , Palato Mole/efeitos dos fármacos , Palato Mole/patologia , Polissonografia/métodos , Coelhos , Distribuição Aleatória , Apneia Obstrutiva do Sono/etiologia , Tomografia Computadorizada Espiral/métodos
10.
Zhonghua Nan Ke Xue ; 21(9): 816-8, 2015 Sep.
Artigo em Zh | MEDLINE | ID: mdl-26552215

RESUMO

OBJECTIVE: To search for an optimum method for testicular prothesis implantation in the treatment of testis loss. METHODS: We retrospectively analyzed the surgical methods and outcomes of 53 cases of terminal prostate cancer and 4 cases of unilateral testicular torsion treated by implantation of testicular prothesis with the polypropylene mesh. RESULTS: The 57 male patients all received testicular prothesis with the polypropylene mesh. All the patients were satisfied with the appearance and size of the scrotum after surgery. No scrotal hematoma, prosthesis infection, or autoimmune disease occurred postoperatively. CONCLUSION: Testis loss is not a rare condition clinically, for the treatment of which surgical implantation of testicular prothesis with the polypropylene mesh can achieve both a fine tissue compatibility and a desirable scrotal appearance.


Assuntos
Polipropilenos , Neoplasias da Próstata/cirurgia , Próteses e Implantes , Escroto , Torção do Cordão Espermático/cirurgia , Telas Cirúrgicas , Testículo , Humanos , Masculino , Estudos Retrospectivos
11.
Angew Chem Int Ed Engl ; 54(24): 7042-6, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-25925551

RESUMO

Stereocomplexation is the stereoselective interaction between two opposite enantiomeric polymers through an interlocked orderly assembly. Most studies focus on the stereocomplex formation from the crystalline opposite enantiomers having the identical structure; nevertheless, rare examples were reported regarding the crystalline stereocomplexes from enantiomeric polymers having different chemical structures. Herein we show a strategy for polymer orderly assembly through the formation of crystalline hetero-stereocomplexed polymeric materials by the cocrystallization of amorphous isotactic polycarbonates with different chemical structures and opposite configurations. The behaviors in the crystalline state are significantly different from that of the component enantiomeric polymers or their homo-stereocomplexes. This study is expected to open up a new way to prepare various semicrystalline materials having a wide variety of physical properties and degradability.


Assuntos
Cimento de Policarboxilato/química , Varredura Diferencial de Calorimetria , Dióxido de Carbono/química , Cristalização , Compostos de Epóxi/química , Estereoisomerismo
12.
Shanghai Kou Qiang Yi Xue ; 33(2): 180-185, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-39005096

RESUMO

PURPOSE: To investigate the efficacy of a modified maxillary protraction appliance in patients of skeletal Class Ⅲ with crowding. METHODS: Forty patients with skeletal Class Ⅲ malocclusion were divided into two groups, with 20 patients in each group. The experimental group had molar in a neutral or distal relationship and applied a modified maxillary protraction appliance, while the control group had molar mesial relationship and applied a conventional maxillary protraction appliance. Lateral cephalometric radiographs were taken before and after treatment in both groups for comparison. SPSS 22.0 software package was used for data analysis. RESULTS: The angle measurements taken before and after treatment showed a significant increase in SNA, ANB, SN-MP and U4-SN(P<0.01), while SNB decreased(P<0.01) in both groups. SN-OL changes were statistically different before and after treatment in the experimental group(P<0.05). The sagittal measurements before and after treatment in both groups showed significant alterations in all(P<0.05) but the length of the maxillary arch in both groups. For vertical measurements, U1-PP, L1-MP, U4-SN, U6-SN, and ANS-ME all increased (P<0.05), while the changes of U4-PP and U6-PP in the two groups before and after treatment were statistically different(P<0.05). Compared with the control group, the experimental group had a significantly increased maxillary arch length, a more remote location at U6, and a less variable molar relationship after treatment(P<0.01). The two groups showed a variable amount of cephalometric measurements before and after treatment: the experimental group had a significant increase in maxillary arch length, a more remote position at U6, and a smaller change in molar relationship compared to the control group(P<0.01). CONCLUSIONS: The modified maxillary protraction appliance showed good results for maxillary protraction and pushing the molar distally in patients with skeletal Class Ⅲ with crowding at neutral or distal molar relationship.


Assuntos
Cefalometria , Má Oclusão Classe III de Angle , Maxila , Humanos , Má Oclusão Classe III de Angle/terapia , Má Oclusão/terapia
13.
Int J Oral Sci ; 16(1): 40, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740746

RESUMO

Oxidative stress is increasingly recognized as a major contributor to the pathophysiology of Alzheimer's disease (AD), particularly in the early stages of the disease. The multiplicity advantages of stem cell transplantation make it fascinating therapeutic strategy for many neurodegenerative diseases. We herein demonstrated that human dental pulp stem cells (hDPSCs) mediated oxidative stress improvement and neuroreparative effects in in vitro AD models, playing critical roles in regulating the polarization of hyperreactive microglia cells and the recovery of damaged neurons. Importantly, these therapeutic effects were reflected in 10-month-old 3xTg-AD mice after a single transplantation of hDPSCs, with the treated mice showing significant improvement in cognitive function and neuropathological features. Mechanistically, antioxidant and neuroprotective effects, as well as cognitive enhancements elicited by hDPSCs, were at least partially mediated by Nrf2 nuclear accumulation and downstream antioxidant enzymes expression through the activation of the AKT-GSK3ß-Nrf2 signaling pathway. In conclusion, our findings corroborated the neuroprotective capacity of hDPSCs to reshape the neuropathological microenvironment in both in vitro and in vivo AD models, which may be a tremendous potential therapeutic candidate for Alzheimer's disease.


Assuntos
Doença de Alzheimer , Polpa Dentária , Glicogênio Sintase Quinase 3 beta , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Polpa Dentária/citologia , Doença de Alzheimer/terapia , Fator 2 Relacionado a NF-E2/metabolismo , Humanos , Animais , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Modelos Animais de Doenças , Transplante de Células-Tronco , Células-Tronco , Camundongos Transgênicos
14.
Head Face Med ; 20(1): 31, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745246

RESUMO

BACKGROUND: In this study, we sought to quantify the influence of vertical control assisted by a temporary anchorage device (TAD) on orthodontic treatment efficacy for skeletal class II patients with a hyperdivergent facial type and probe into the critical factors of profile improvement. METHODS: A total of 36 adult patients with skeletal class II and a hyperdivergent facial type were included in this retrospective case-control study. To exclude the effect of sagittal anchorage reinforcement, the patients were divided into two groups: a maxillary maximum anchorage (MMA) group (N = 17), in which TADs were only used to help with anterior tooth retraction, and the MMA with vertical control (MMA + VC) group (N = 19), for which TADs were also used to intrude the maxillary molars and incisors. The treatment outcome was evaluated using dental, skeletal, and soft-tissue-related parameters via a cephalometric analysis and cast superimposition. RESULTS: A significant decrease in ANB (P < 0.05 for both groups), the retraction and uprighting of the maxillary and mandibular incisors, and the retraction of protruded upper and lower lips were observed in both groups. Moreover, a significant intrusion of the maxillary molars was observed via the cephalometric analysis (- 1.56 ± 1.52 mm, P < 0.05) and cast superimposition (- 2.25 ± 1.03 mm, P < 0.05) of the MMA + VC group but not the MMA group, which resulted in a remarkable decrease in the mandibular plane angle (- 1.82 ± 1.38°, P < 0.05). The Z angle (15.25 ± 5.30°, P < 0.05) and Chin thickness (- 0.97 ± 0.45°, P < 0.05) also improved dramatically in the MMA + VC group, indicating a better profile and a relaxed mentalis. Multivariate regression showed that the improvement in the soft tissue was closely related to the counterclockwise rotation of the mandible plane (P < 0.05). CONCLUSIONS: TAD-assisted vertical control can achieve intrusion of approximately 2 mm for the upper first molars and induce mandibular counterclockwise rotation of approximately 1.8°. Moreover, it is especially important for patients without sufficient retraction of the upper incisors or a satisfactory chin shape.


Assuntos
Cefalometria , Má Oclusão Classe II de Angle , Humanos , Má Oclusão Classe II de Angle/terapia , Má Oclusão Classe II de Angle/diagnóstico por imagem , Feminino , Masculino , Estudos Retrospectivos , Adulto , Estudos de Casos e Controles , Adulto Jovem , Resultado do Tratamento , Procedimentos de Ancoragem Ortodôntica/métodos , Procedimentos de Ancoragem Ortodôntica/instrumentação , Ortodontia Corretiva/métodos , Técnicas de Movimentação Dentária/métodos , Dimensão Vertical , Adolescente
15.
Front Med (Lausanne) ; 11: 1339573, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487022

RESUMO

Bone defects resulting from severe trauma, tumors, inflammation, and other factors are increasingly prevalent. Stem cell-based therapies have emerged as a promising alternative. Dental pulp stem cells (DPSCs), sourced from dental pulp, have garnered significant attention owing to their ready accessibility and minimal collection-associated risks. Ongoing investigations into DPSCs have revealed their potential to undergo osteogenic differentiation and their capacity to secrete a diverse array of ontogenetic components, such as extracellular vesicles and cell lysates. This comprehensive review article aims to provide an in-depth analysis of DPSCs and their secretory components, emphasizing extraction techniques and utilization while elucidating the intricate mechanisms governing bone regeneration. Furthermore, we explore the merits and demerits of cell and cell-free therapeutic modalities, as well as discuss the potential prospects, opportunities, and inherent challenges associated with DPSC therapy and cell-free therapies in the context of bone regeneration.

16.
ACS Appl Mater Interfaces ; 16(23): 30430-30442, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38814614

RESUMO

Patients with open abdominal (OA) wounds have a mortality risk of up to 30%, and the resulting disabilities would have profound effects on patients. Here, we present a novel double-sided adhesive tape developed for the management of OA wounds. The tape features an asymmetrical structure and employs an acellular dermal matrix (ADM) with asymmetric wettability as a scaffold. It is constructed by integrating a tissue-adhesive hydrogel composed of polydopamine (pDA), quaternary ammonium chitosan (QCS), and acrylic acid cross-linking onto the bottom side of the ADM. Following surface modification with pDA, the ADM would exhibit characteristics resistant to bacterial adhesion. Furthermore, the presence of a developed hydrogel ensures that the tape not only possesses tissue adhesiveness and noninvasive peelability but also effectively mitigates damage caused by oxidative stress. Besides, the ADM inherits the strength of the skin, imparting high burst pressure tolerance to the tape. Based on these remarkable attributes, we demonstrate that this double-sided (D-S) tape facilitates the repair of OA wounds, mitigates damage to exposed intestinal tubes, and reduces the risk of intestinal fistulae and complications. Additionally, the D-S tape is equally applicable to treating other abdominal injuries, such as gastric perforations. It effectively seals the perforation, promotes injury repair, and prevents the formation of postoperative adhesions. These notable features indicate that the presented double-sided tape holds significant potential value in the biomedical field.


Assuntos
Traumatismos Abdominais , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Quitosana/química , Quitosana/farmacologia , Camundongos , Polímeros/química , Polímeros/farmacologia , Humanos , Indóis/química , Indóis/farmacologia , Cicatrização/efeitos dos fármacos , Pressão , Masculino , Ratos
17.
World J Otorhinolaryngol Head Neck Surg ; 10(2): 113-120, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855290

RESUMO

Objective: This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China. Methods: This study was conducted by 45 tertiary Grade-A hospitals in China. Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders. Results: Complete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self-reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms. Conclusions: The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China. Incidence and prognosis are influenced by several factors, including sex, SARS-CoV-2 vaccination, history of head-facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.

18.
Macromol Rapid Commun ; 34(19): 1563-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23996916

RESUMO

Rocket-like vesicles formed are composed of poly(acrylic aicd) (PMAA )/poly(ethylene glycol) (PEG) complex coated hollow silica spheres, and the structure and composition of the vesicles are characterized using TGA, (1)H NMR, FTIR, and TEM. Although only one-third of EG units of PEG brushes grafted to hollow silica spheres form the complex with PMAA via hydrogen bonding, the first "booster" layer composed of PMAA/PEG complex can provide secure encapsulation of model compound calcein blue under an acidic condition. The second "booster" layer composed of PEG brushes can be formed by changing acidic pH to 7.4 through the disassociation of the PMAA/PEG complex. A higher molecular weight PMAA exhibits a faster disassembly due to the formation of a looser PMAA/PEG complex on the surfaces of hollow silica spheres.


Assuntos
Portadores de Fármacos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Dióxido de Silício/química , Resinas Acrílicas/química , Concentração de Íons de Hidrogênio , Propriedades de Superfície
19.
J Sep Sci ; 36(12): 1925-34, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23936912

RESUMO

An efficient separation process of flavonoid from Taxus wallichiana var. mairei remainder extracts free of taxoids was developed in this study. AB-8 macroporous resin and polyamide resin offered the fine adsorption capacity, and its adsorption rate at 30°C fitted well to the Langmuir and Freundich isotherms. Resin dynamic adsorption and desorption experiments were conducted to optimize the separation process of total flavonoids from T. wallichiana var. mairei remainder extracts free of taxoids. The optimum parameters for adsorption by AB-8 resin were as follows: (1) the concentration of flavonoids in a sample solution of 5.61 mg/mL with a processing volume of 2 bed volume (BV) (60 mL); (2) for desorption, ethanol-water (80:20, v/v), with 6 BV as an eluent at a flow rate of 2 BV/h. After a one-run treatment with AB-8 resin, the content of flavonoids was increased 5.10-fold from 4.05 to 20.65%. The optimum parameters for adsorption by polyamide resin were as follows: processing volume of 2 BV (30 mL); for desorption, ethanol-water (70:30, v/v), with 8 BV as an eluent at a flow rate of 2 BV/h. After one-run treatment with polyamide resin, the content of total flavonoids increased from 20.65 to 65.21%. The method will provide a potential approach for large-scale separation and purification of flavonoid for its wide pharmaceutical use.


Assuntos
Cromatografia/métodos , Flavonoides/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Resinas Sintéticas/química , Taxoides/análise , Taxus/química , Adsorção , Cromatografia/instrumentação , Flavonoides/química , Nylons/química , Extratos Vegetais/química , Poliestirenos/química
20.
Nano Lett ; 12(4): 2003-12, 2012 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-22372996

RESUMO

With the intense international response to the AIDS pandemic, HIV vaccines have been extensively investigated but have failed due to issues of safety or efficacy in humans. Adjuvants for HIV/AIDS vaccines are under intense research but a rational design approach is still lacking. Nanomaterials represent an obvious opportunity in this field due to their unique physicochemical properties. Gold nanostructures are being actively studied as a promising and versatile platform for biomedical application. Herein, we report novel surface-engineered gold nanorods (NRs) used as promising DNA vaccine adjuvant for HIV treatment. We have exploited the effects of surface chemistry on the adjuvant activity of the gold nanorod by placing three kinds of molecules, that is, cetyltrimethylammonium bromide (CTAB), poly(diallydimethylammonium chloride) (PDDAC), and polyethyleneimine (PEI) on the surface of the nanorod. These PDDAC- or PEI-modified Au NRs can significantly promote cellular and humoral immunity as well as T cell proliferation through activating antigen-presenting cells if compared to naked HIV-1 Env plasmid DNA treatment in vivo. These findings have shed light on the rational design of low-toxic nanomaterials as a versatile platform for vaccine nanoadjuvants/delivery systems.


Assuntos
Genes env/imunologia , Ouro/química , HIV-1/imunologia , Nanopartículas Metálicas/química , Vacinas de DNA/imunologia , Cetrimônio , Compostos de Cetrimônio/química , HIV-1/genética , Humanos , Polietilenoimina/química , Polietilenos/química , Compostos de Amônio Quaternário/química , Propriedades de Superfície , Vacinas de DNA/genética
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