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1.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33783485

RESUMO

Tumor suppressor genes (TSGs) exhibit distinct evolutionary features. We speculated that TSG promoters could have evolved specific features that facilitate their tumor-suppressing functions. We found that the promoter CpG dinucleotide frequencies of TSGs are significantly higher than that of non-cancer genes across vertebrate genomes, and positively correlated with gene expression across tissue types. The promoter CpG dinucleotide frequencies of all genes gradually increase with gene age, for which young TSGs have been subject to a stronger evolutionary pressure. Transcription-related features, namely chromatin accessibility, methylation and ZNF263-, SP1-, E2F4- and SP2-binding elements, are associated with gene expression. Moreover, higher promoter CpG dinucleotide frequencies and chromatin accessibility are positively associated with the ability of TSGs to resist downregulation during tumorigenesis. These results were successfully validated with independent datasets. In conclusion, TSGs evolved specific promoter features that optimized cancer resistance through achieving high expression in normal tissues and resistance to downregulation during tumorigenesis.


Assuntos
Cromatina/metabolismo , Biologia Computacional/métodos , Resistencia a Medicamentos Antineoplásicos/genética , Evolução Molecular , Genes Supressores de Tumor , Neoplasias/genética , Regiões Promotoras Genéticas , Antineoplásicos/uso terapêutico , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Cromatina/ultraestrutura , Ilhas de CpG , Metilação de DNA , Conjuntos de Dados como Assunto , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Anotação de Sequência Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Domínios e Motivos de Interação entre Proteínas , Transcrição Gênica
2.
J Nanobiotechnology ; 20(1): 259, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672708

RESUMO

Patients with diabetic foot ulcers usually suffer from inefficient epithelisation and angiogenesis accompanied by chronic wound healing. Diabetic foot ulcers remain a major challenge in clinical medicine; however, traditional treatments are incapable of transdermal drug delivery, resulting in a low drug delivery rate. We report the development of Ti2C3 MXenes-integrated poly-γ-glutamic acid (γ-PGA) hydrogel microneedles to release asiaticoside (MN-MXenes-AS). Asiaticoside was loaded into PGA-MXenes hydrogel to facilitate cell proliferation while regulating angiogenesis. The characterisation and mechanical strength of the microneedles were investigated in vitro, and the wound-healing efficacy of the microneedles was confirmed in diabetic mice. MXenes significantly improved the mechanical strength of microneedles, while γ-PGA hydrogels provided a moist microenvironment for wound healing. Mice treated with MN-MXenes-AS demonstrated obvious improvements in wound healing process. We successfully fabricated an MXenes-integrated microneedle that possesses sufficient rigidity to penetrate the cuticle for subcutaneous drug delivery, thereby accelerating diabetic wound healing. We demonstrated that MN-MXenes-AS is effective in promoting growth both in vivo and in vitro. Collectively, our data show that MN-MXenes-AS accelerated the healing of diabetic foot ulcers, supporting the use of these microneedles in the treatment of chronic wounds.


Assuntos
Diabetes Mellitus Experimental , Pé Diabético , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Pé Diabético/tratamento farmacológico , Humanos , Hidrogéis , Camundongos , Triterpenos , Cicatrização
3.
J Nanobiotechnology ; 20(1): 60, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35109862

RESUMO

The localization of invisible and impalpable small pulmonary nodules has become an important concern during surgery, since current widely used techniques for localization have a number of limitations, such as invasive features of hookwires and microcoils, and rapid diffusion after injection of indocyanine green (ICG). Lanthanide-based metal-organic frameworks (MOFs) have been proven as potential fluorescent agents because of their prominent luminescent characteristics, including large Stokes shifts, high quantum yields, long decay lifetimes, and undisturbed emissive energies. In addition, lanthanides, such as Eu, can efficiently absorb X-rays for CT imaging. In this study, we synthesized Eu-UiO-67-bpy (UiO = University of Oslo, bpy = 2,2'-bipyridyl) as a fluorescent dye with a gelatin-methacryloyl (GelMA) hydrogel as a liquid carrier. The prepared complex exhibits constant fluorescence emission owing to the luminescent characteristics of Eu and the stable structure of UiO-67-bpy with restricted fluorescence diffusion attributed to the photocured GelMA. Furthermore, the hydrogel provides stiffness to make the injection site tactile and improve the accuracy of localization and excision. Finally, our complex enables fluorescence-CT dual-modal imaging of the localization site.


Assuntos
Elementos da Série dos Lantanídeos , Estruturas Metalorgânicas , Difusão , Gelatina/química , Hidrogéis/química
4.
Audiol Neurootol ; 26(2): 102-110, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33508832

RESUMO

OBJECTIVE: The aim of this study was to investigate sclerostin (SOST) expression in a rat model of experimental tympanosclerosis (TS) and its possible role in the formation of TS. MATERIALS AND METHODS: Thirty-four SD rats were randomly divided into 2 groups: experimental group (n = 17) and normal group (n = 17). The left tympanic cavities in the experimental group were inoculated with methicillin-resistant Staphylococcus aureus. The changes of tympanic membranes were examined and recorded under otoendoscope. Haematoxylin-eosin staining was adopted to detect the morphological changes in the tympanic membrane and middle ear mucosa. Immunohistochemistry and Western blot analysis were used to observe the expression of SOST, Wnt3a, ß-catenin, and P-ERK1/2. RESULTS: In the experimental group, sclerotic lesions were observed in 54.5% ears in the end of 6 weeks. Morphological changes such as mucosa incrassation, inflammatory cells infiltration, fibrous tissue proliferation, and interstitial tissue incrassation prominently appeared in the tympanic membrane and middle ear mucosa. SOST protein was mainly distributed in the cytoplasm of epithelial cells and gland cells, the expression of which increased significantly in the calcified experimental ears. In addition, expression levels of Wnt3a, ß-catenin, and P-ERK1/2 increased significantly in the calcified group too. CONCLUSION: The upregulated expression level of SOST may be involved in the formation of TS, first, through the pro-phosphorylation of ERK1/2 in the inflammatory stage, and then through the enhancement of Wnt3a in the osteogenic stage.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Miringoesclerose/metabolismo , Membrana Timpânica/metabolismo , Animais , Modelos Animais de Doenças , Orelha Média/metabolismo , Orelha Média/microbiologia , Orelha Média/patologia , Marcadores Genéticos , Masculino , Staphylococcus aureus Resistente à Meticilina , Miringoesclerose/microbiologia , Miringoesclerose/patologia , Ratos , Ratos Sprague-Dawley , Membrana Timpânica/patologia , beta Catenina/metabolismo
5.
Gastroenterology ; 155(2): 383-390.e8, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29729257

RESUMO

BACKGROUND & AIMS: Colorectal cancer (CRC) development has been associated with increased proportions of Bacteroides fragilis and certain Streptococcus, Fusobacterium, and Peptostreptococcus species in the intestinal microbiota. We investigated associations between bacteremia from specific intestinal microbes and occurrence of CRC. METHODS: We performed a retrospective study after collecting data on 13,096 adult patients (exposed group) in Hong Kong hospitalized with bacteremia (identified by blood culture test) without a previous diagnosis of cancer from January 1, 2006 through December 31, 2015. We collected data on intestinal microbes previously associated with CRC (genera Bacteroides, Clostridium, Filifactor, Fusobacterium, Gemella, Granulicatella, Parvimonas, Peptostreptococcus, Prevotella, Solobacterium, and Streptococcus). Clinical information, including patient demographics, comorbid medical conditions, date of bacteremia, and bacterial species identified, were collected. The incidence of biopsy-proved CRC was compared between the exposed and unexposed (patients without bacteremia matched for age, sex, and comorbidities) groups. RESULTS: The risk of CRC was increased in patients with bacteremia from B fragilis (hazard ratio [HR] = 3.85, 95% CI = 2.62-5.64, P = 5.5 × 10-12) or Streptococcus gallolyticus (HR = 5.73, 95% CI = 2.18-15.1, P = 4.1 × 10-4) compared with the unexposed group. In addition, the risk of CRC was increased in patients with bacteremia from Fusobacterium nucleatum (HR = 6.89, 95% CI = 1.70-27.9, P = .007), Peptostreptococcus species (HR = 3.06, 95% CI = 1.47-6.35, P = .003), Clostridium septicum (HR = 17.1, 95% CI = 1.82-160, P = .013), Clostridium perfringens (HR = 2.29, 95% CI = 1.16-4.52, P = .017), or Gemella morbillorum (HR = 15.2, 95% CI = 1.54-150, P = .020). We observed no increased risk in patients with bacteremia caused by microbes not previously associated with colorectal neoplasms. CONCLUSIONS: In a retrospective analysis of patients hospitalized for bacteremia, we associated later diagnosis of CRC with B fragilis and S gallolyticus and other intestinal microbes. These bacteria might have entered the bloodstream from intestinal dysbiosis and perturbed barrier function. These findings support a model in which specific members of the intestinal microbiota promote colorectal carcinogenesis. Clinicians should evaluate patients with bacteremia from these species for neoplastic lesions in the colorectum.


Assuntos
Bacteriemia/microbiologia , Colo/microbiologia , Neoplasias Colorretais/sangue , Disbiose/sangue , Microbioma Gastrointestinal , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteroides fragilis/isolamento & purificação , Bacteroides fragilis/patogenicidade , Biópsia , Carcinogênese , Colo/patologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/microbiologia , Disbiose/diagnóstico , Disbiose/epidemiologia , Disbiose/microbiologia , Feminino , Hong Kong/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Streptococcus gallolyticus/isolamento & purificação , Streptococcus gallolyticus/patogenicidade
6.
Gastroenterology ; 155(2): 529-541.e5, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29689266

RESUMO

BACKGROUND & AIMS: Patients with colorectal cancer (CRC) have a different gut microbiome signature than individuals without CRC. Little is known about the viral component of CRC-associated microbiome. We aimed to identify and validate viral taxonomic markers of CRC that might be used in detection of the disease or predicting outcome. METHODS: We performed shotgun metagenomic analyses of viromes of fecal samples from 74 patients with CRC (cases) and 92 individuals without CRC (controls) in Hong Kong (discovery cohort). Viral sequences were classified by taxonomic alignment against an integrated microbial reference genome database. Viral markers associated with CRC were validated using fecal samples from 3 separate cohorts: 111 patients with CRC and 112 controls in Hong Kong, 46 patients with CRC and 63 controls in Austria, and 91 patients with CRC and 66 controls in France and Germany. Using abundance profiles of CRC-associated virome genera, we constructed random survival forest models to identify those associated with patient survival times. RESULTS: The diversity of the gut bacteriophage community was significantly increased in patients with CRC compared with controls. Twenty-two viral taxa discriminated cases from controls with an area under the receiver operating characteristic curve of 0.802 in the discovery cohort. The viral markers were validated in 3 cohorts, with area under the receiver operating characteristic curves of 0.763, 0.736, and 0.715, respectively. Clinical subgroup analysis showed that dysbiosis of the gut virome was associated with early- and late-stage CRC. A combination of 4 taxonomic markers associated with reduced survival of patients with CRC (log-rank test, P = 8.1 × 10-6) independently of tumor stage, lymph node metastases, or clinical parameters. We found altered interactions between bacteriophages and oral bacterial commensals in fecal samples from patients with CRC compared with controls. CONCLUSIONS: In a metagenomic analysis of fecal samples from patients and controls, we identified virome signatures associated with CRC. These data might be used to develop tools to identify individuals with CRC or predict outcomes.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/virologia , Disbiose/virologia , Microbioma Gastrointestinal/genética , Vírus/genética , Áustria/epidemiologia , Estudos de Casos e Controles , Estudos de Coortes , Colonoscopia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Estudos Transversais , Disbiose/diagnóstico por imagem , Fezes/virologia , Feminino , França/epidemiologia , Alemanha/epidemiologia , Hong Kong/epidemiologia , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Análise de Sobrevida
7.
Rheumatology (Oxford) ; 58(5): 803-810, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30561745

RESUMO

OBJECTIVE: Real-world epidemiological data on the risk of tuberculosis (TB) in patients with immune-mediated diseases treated with biologics are scarce in TB endemic areas. We investigated the incidence of TB in a population-based setting and stratified the risk of TB among different biological therapies. METHODS: We collected medical data from a territory-wide computerized database in Hong Kong. We reported the incidence of TB in patients treated with various classes of biologics, and calculated standardized incidence ratio by comparing with the general population. Subgroup analyses were performed based on disease subtypes and biological drugs. RESULTS: Among 2485 subjects with immune-mediated diseases (82.5% rheumatology diseases; 10.6% IBD; 6.9% dermatology diseases), 54 subjects developed active TB during 6921 person-years of follow-up. The mean age (±s.d.) was 43 (14) years, and the median follow-up duration was 24.9 months (interquartile range 4.9-45.0). The overall standardized incidence ratio of TB was 10.91 (95% CI 8.00-13.82), and patients treated with infliximab had a nearly 26 times increased risk of TB compared with the general population (standardized incidence ratio 25.95; 95% CI 17.23-34.67). The risk of TB with TNF inhibitor was higher than with a non-TNF biologic (hazard ratio 4.34; 95% CI 1.31-14.39), while the risk of infliximab was higher than etanercept and adalimumab (hazard ratio: 4.10 and 2.08, respectively). CONCLUSION: The risk of TB is much higher in patients with immune-mediated diseases on biological therapy compared with the general population, and infliximab is associated with the highest risk of TB among the biologics analysed.


Assuntos
Antirreumáticos/efeitos adversos , Produtos Biológicos/efeitos adversos , Doenças do Sistema Imunitário/microbiologia , Doenças Reumáticas/microbiologia , Tuberculose/epidemiologia , Adalimumab/efeitos adversos , Adulto , Bases de Dados Factuais , Etanercepte/efeitos adversos , Feminino , Hong Kong/epidemiologia , Humanos , Doenças do Sistema Imunitário/tratamento farmacológico , Doenças do Sistema Imunitário/imunologia , Incidência , Infliximab/efeitos adversos , Masculino , Pessoa de Meia-Idade , Doenças Reumáticas/tratamento farmacológico , Doenças Reumáticas/imunologia , Fatores de Risco , Tuberculose/induzido quimicamente , Tuberculose/imunologia , Adulto Jovem
8.
Mol Biol Evol ; 34(4): 903-907, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28087780

RESUMO

Focal copy number gains or losses are important genomic hallmarks of cancer. The genomic distribution of oncogenes and tumor-suppressor genes (TSG) in relation to focal copy number aberrations is unclear. Our analysis revealed that the mean distance of TSGs from oncogenes was significantly shorter than that of noncancer genes, suggesting that oncogenes and TSGs tend to be in close physical proximity in the human genome. Such relationship was conserved in mouse and drosophila. Pan-cancer analysis using data from The Cancer Genome Atlas indicated that oncogenes without a nearby TSG are more prone to amplification. In conclusion, our study provides evidence for the nonrandom distribution of oncogenes and TSGs across different species. Our data also support that the existence of a neighboring TSG can suppress amplification of an oncogene, shedding new light on a previously unappreciated protective mechanism of TSGs.


Assuntos
Amplificação de Genes/genética , Genes Supressores de Tumor/fisiologia , Oncogenes/genética , Animais , Bases de Dados de Ácidos Nucleicos , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica/genética , Genômica , Humanos , Mutação , Neoplasias/genética
9.
Mikrochim Acta ; 185(10): 458, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30218157

RESUMO

A composite consisting of graphene oxide and gold nanorods (GO-GNRs) was designed for the trace determination of hepatitis B surface antigen (HBsAg) using surface enhanced Raman spectroscopy (SERS). GO contains numerous carboxy and hydroxy groups on its surface and therefore can serve as the substrate for decoration with GNRs and for immobilizing antibody against HBsAg. The GNRs (carrying the SERS probe 2-mercaptopyridine) exhibit high SERS activity, and this improves the sensitivity of the biosensor. The antibody on the GO-GNRs binds HBsAg with high specificity, and it results in excellent selectivity. The SERS signal (measured at 1002 cm-1) increases in the 1-1000 pg·mL-1 HBsAg concentrations range, and the limit of detection is 0.05 pg·mL-1 (at an S/N ratio of 3). The immunoassay achieves the sensitive and selective determination of HBsAg in serum and expands the potential application of GO-GNR based SERS tag in clinical research. Graphical abstract A novel graphene oxide-gold nanorod (GO-GNRs) based surface-enhanced Raman scattering (SERS) tag for immunoassay was designed. It allows for sensitive and selective determination of HBsAg in serum. The method is expected to expand the potential application in the environment, in medicine and in food analysis.


Assuntos
Ouro/química , Grafite/química , Antígenos de Superfície da Hepatite B/análise , Imunoensaio/métodos , Nanotubos/química , Óxidos/química , Análise Espectral Raman , Humanos , Modelos Moleculares , Conformação Molecular , Propriedades de Superfície
10.
Emerg Infect Dis ; 23(10): 1671-1679, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28930010

RESUMO

Cross-sectional studies suggest an increasing trend in incidence and relatively low recurrence rates of Clostridium difficile infections in Asia than in Europe and North America. The temporal trend of C. difficile infection in Asia is not completely understood. We conducted a territory-wide population-based observational study to investigate the burden and clinical outcomes in Hong Kong, China, over a 9-year period. A total of 15,753 cases were identified, including 14,402 (91.4%) healthcare-associated cases and 817 (5.1%) community-associated cases. After adjustment for diagnostic test, we found that incidence increased from 15.41 cases/100,000 persons in 2006 to 36.31 cases/100,000 persons in 2014, an annual increase of 26%. This increase was associated with elderly patients, for whom incidence increased 3-fold over the period. Recurrence at 60 days increased from 5.7% in 2006 to 9.1% in 2014 (p<0.001). Our data suggest the need for further surveillance, especially in Asia, which contains ≈60% of the world's population.


Assuntos
Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/epidemiologia , Infecção Hospitalar/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Clostridium/microbiologia , Infecções por Clostridium/mortalidade , Infecções Comunitárias Adquiridas , Infecção Hospitalar/microbiologia , Infecção Hospitalar/mortalidade , Estudos Transversais , Monitoramento Epidemiológico , Feminino , Hong Kong/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva , Análise de Sobrevida
11.
Ecotoxicol Environ Saf ; 135: 24-31, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27677079

RESUMO

Avermectins (AVMs) are used worldwide in agriculture and veterinary medicine. Residues of avermectin drugs, causing toxicological effects on non-target organisms, have raised great concern. The aim of this study was to investigate the effects of AVM on the expression levels of alpha synuclein (α-Syn) and proteasomal activity in pigeon (Columba livia) neurons both in vivo and in vitro. The results showed that, the mRNA and protein levels of α-Syn increased in AVM treated groups relative to control groups in the cerebrum, cerebellum and optic lobe in vivo. Dose-dependent decreases in the proteasomal activity (i.e., chymotrypsin-like, trypsin-like and peptidylglutamyl peptidehydrolase) were observed both in vivo and in vitro. The results suggested that AVM could induce the expression levels of α-Syn and inhibit the normal physiological function of proteasome in brain tissues and neurons. The information presented in this study is helpful to understand the mechanism of AVM-induced neurotoxicology in birds.


Assuntos
Columbidae/metabolismo , Monitoramento Ambiental/métodos , Poluentes Ambientais/toxicidade , Ivermectina/análogos & derivados , Complexo de Endopeptidases do Proteassoma/metabolismo , alfa-Sinucleína/biossíntese , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células Cultivadas , China , Relação Dose-Resposta a Droga , Ivermectina/toxicidade , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Cultura Primária de Células , RNA Mensageiro/metabolismo
13.
J Nanosci Nanotechnol ; 16(1): 939-43, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27398550

RESUMO

Herein, we report the green synthesis of Ag and Au@Ag microspheres by using the aqueous extracts of the egg white as well as their application as substrates for surface-enhanced Raman spectroscopy (SERS) detection. Both microspheres are prepared via the green synthesis method (room temperature, in aqueous solution and a benign reducer). The as-prepared urchin-like Ag microspheres have an average diameter of 600-800 nm, which is made up of some nanopricks with an average length of 10-40 nm. Meanwhile, the Au@Ag architectures prepared by galvanic replacement keep nearly similar size, which is also composed of some compact nanoparticles with an average diameter of about 10-40 nm. These products are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electronic microscopy (TEM), and Fourier transform infrared spectrophotometer (FTIR). The study on SERS activities is also carried out for both microspheres. It is found that Au@Ag microspheres possess much higher SERS activity than Ag microspheres. Our work may shed light on the design and synthesis of self-assembled 3D micro/nano-architectures for the use of SERS, catalysis, biosensors, nanomedicine, etc.


Assuntos
Ligas/química , Clara de Ovo/química , Ouro/química , Microesferas , Prata/química , Animais , Galinhas , Tamanho da Partícula , Análise Espectral Raman
14.
Ecotoxicol Environ Saf ; 110: 95-102, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25202854

RESUMO

The expression of heat shock proteins (Hsps) commonly increases to provide neuroprotection when brain tissues are under stress conditions. Residues of avermectins (AVMs) have neurotoxic effects on a number of non-target organisms. The aim of this study was to investigate the effects of AVM exposure on the expression levels of Hsp 60, Hsp 70 and Hsp 90 for pigeon (Columba livia) neurons both in vivo and in vitro. The results showed that in general, the mRNA and protein levels of Hsps were increased in treated groups relative to control groups after AVM exposure for 30d, 60d and 90d in the cerebrum, cerebellum and optic lobe in vivo. However, AVM exposure had no significant effects on the transcription expression of Hsps for 90d in the optic lobe and decreased the translation expression of Hsps significantly for 90d in the optic lobe. In vitro, the LC50 of avermectin for King pigeon neurons is between 15µgL(-1) and 20µgL(-1). Following AVM (2.5-20µgL(-1)) exposure, the mRNA expression of the 3 Hsps was up-regulated to different degrees. Compared with the control groups, a significant decrease, a remarkable increase and a non-significant change was found in the protein expression of Hsp 60, Hsp 70 and Hsp 90 separately following AVM (2.5-20µgL(-1)) exposure. Based on these results, we conclude that AVM exposure can induce a protective stress response in pigeons by means of promoting the mRNA and protein expression of Hsps under in vivo and in vitro conditions, thus easing the neurotoxic effects of AVM to some extent.


Assuntos
Chaperonina 60/genética , Columbidae/genética , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP90/genética , Ivermectina/análogos & derivados , Animais , Encéfalo/metabolismo , Chaperonina 60/metabolismo , Columbidae/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Ivermectina/toxicidade , Dose Letal Mediana , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica
15.
ACS Biomater Sci Eng ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38913499

RESUMO

Diabetic bone defects, exacerbated by hyperglycemia-induced inflammation and oxidative stress, present significant therapeutic challenges. This study introduces a novel injectable scaffold, MgH2@PLGA/F-GM, consisting of foamed gelatin-methacryloyl (GelMA) and magnesium hydride (MgH2) microspheres encapsulated in poly(lactic-co-glycolic acid) (PLGA). This scaffold is uniquely suited for diabetic bone defects, conforming to complex shapes and fostering an environment conducive to tissue regeneration. As it degrades, Mg(OH)2 is released and dissolved by PLGA's acidic byproducts, releasing therapeutic Mg2+ ions. These ions are instrumental in macrophage phenotype modulation, inflammation reduction, and angiogenesis promotion, all vital for diabetic bone healing. Additionally, hydrogen (H2) released during degradation mitigates oxidative stress by diminishing reactive oxygen species (ROS). This multifaceted approach not only reduces ROS and inflammation but also enhances M2 macrophage polarization and cell migration, culminating in improved angiogenesis and bone repair. This scaffold presents an innovative strategy for addressing the complexities of diabetic bone defect treatment.

16.
Mater Today Bio ; 24: 100938, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38260033

RESUMO

Postoperative complications at the anastomosis site following tracheal resection are a prevalent and substantial concern. However, most existing solutions primarily focus on managing symptoms, with limited attention given to proactively preventing the underlying pathological processes. To address this challenge, we conducted a drug screening focusing on clinically-relevant polyphenolic compounds, given the growing interest in polyphenolic compounds for their potential role in tissue repair during wound healing. This screening led to the identification of resveratrol as the most promising candidate for mitigating tracheal complications, as it exhibited the most significant efficacy in enhancing the expression of vascular endothelial growth factor (VEGF) while concurrently suppressing the pivotal fibrosis factor: transforming growth factor-beta 1 (TGF-ß1), showcasing its robust potential in addressing these issues. Building upon this discovery, we further developed an innovative photosensitive poly-L-lysine gel integrated with a resveratrol-magnesium metal polyphenol network (MPN), named Res-Mg/PL-MA. This design allows for the enables sustained release of resveratrol and synergistically enhances the expression of VEGF and also promotes resistance to tensile forces, aided by magnesium ions, in an anastomotic tracheal fistula animal models. Moreover, the combination of resveratrol and poly-L-lysine hydrogel effectively inhibits bacteria, reduces local expression of key inflammatory factors, and induces polarization of macrophages toward an anti-inflammatory phenotype, as well as inhibits TGF-ß1, consequently decreasing collagen production levels in an animal model of post-tracheal resection. In summary, our novel Res-Mg/PL-MA hydrogel, through antibacterial, anti-inflammatory, and pro-vascularization mechanisms, effectively prevents complications at tracheal anastomosis, offering significant promise for translational applications in patients undergoing tracheal surgeries.

17.
ACS Omega ; 8(31): 27920-27931, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37576626

RESUMO

Bone fractures have always been a burden to patients due to their common occurrence and severe complications. Traditionally, operative treatments have been widely used in the clinic for implanting, despite the fact that they can only achieve bone fixation with limited stability and pose no effect on promoting tissue growth. In addition, the nondegradable implants usually need a secondary surgery for implant removal, otherwise they may block the regeneration of bones resulting in bone nonunion. To overcome the low degradability of implants and avoid multiple surgeries, tissue engineers have investigated various biodegradable materials for bone regeneration, whereas the significance of stability of long-term bone fixation tends to be neglected during this process. Combining the traditional orthopedic implantation surgeries and emerging tissue engineering, we believe that both bone fixation and bone regeneration are indispensable factors for a successful bone repair. Herein, we define such a novel idea as bone regenerative fixation (BRF), which should be the main future development trend of biodegradable materials.

18.
Smart Mater Med ; 4: 514-521, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37038409

RESUMO

Alleviating excessive inflammation while accelerating chronic wound healing to prevent wound infection has remained challenging, especially during the coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 when patients experienced difficulties with receive appropriate healthcare. We addressed this issue by developing handheld electrospun aloe-nanofiber membranes (ANFMs) with convenient, environmentally friendly properties and a therapeutic capacity for wound closure. Our results showed that ANFMs fabricated with high molecular weight polyvinyl alcohol (PVA) to form fibers during electrospinning had uniform fibrous architecture and a porous structure. Given the value of aloe gel in accelerating wound healing, liquid extracts from ANFMs significantly downregulated the expression of the pro-inflammatory genes, interleukin-6 (IL-6) and inducible nitric oxide synthase (iNOS), and markedly suppress the generation of reactive oxygen species (ROS) induced by lipopolysaccharide in RAW264.7 macrophages. These results indicated the excellent antioxidant and anti-inflammatory effects of ANFMs. After implantation into a mouse diabetic wound model for 12 days in situ, ANFMs notably expedited chronic wound healing via promoting angiogenesis and enhancing cell viability. Our ANFMs generated by handheld electrospinning in situ healed chronic wounds offer a convenient and promising alternative for patients to heal their own wounds under variable conditions.

19.
Theranostics ; 13(11): 3675-3688, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37441591

RESUMO

Hair loss is a growing esthetic condition driven by complex mechanisms that has numerous psycho-social implications. Conventional drug applications usually focus on a single treatment target, and the penetration depth restricts the post-delivery effect. Method: We fabricated a curcumin-zinc framework (ZnMOF) encapsulated gamma-polyglutamic acid (γ-PGA) microneedle patch (ZnMOF-MN) as a multifunctional biosafe transdermal drug delivery system. ZnMOF was characterized with the field emission scanning electron microscope (FE-SEM), dynamic light scattering (DLS), elemental mapping, and X-ray diffraction (XRD). The topographical and hygroscopic features of ZnMOF-MN were characterized with SEM. The in vitro ZnMOF release profile and the in vivo penetration of ZnMOF-MN were also evaluated. The anti-oxidant, anti-apoptosis, and antiandrogen effects of ZnMOF solution and ZnMOF-MN extract were studied on mouse dermal papilla cells (DPCs). Two animal models (in C57BL/6 mice), including androgenic alopecia (AGA) model and wound healing model, were used to identify the therapeutic effect of ZnMOF-MN on hair regrowth and wound healing in vivo. Hair follicles, surrounding vessels (CD31+), and proliferating cells (Ki67+) were evaluated by histological staining. Results: ZnMOF crystals were cone-shaped nanoparticles with a size distribution of 424.9 ± 59.01 nm. ZnMOF-MN patch can create temporary holes in the skin to directly and evenly deliver bioactive ZnMOF particles to the targeted depth and achieve a steady and sustained release of Zn2+ and curcumin. In vitro, ZnMOF significantly improved the viability of DPCs against the excess reactive oxygen species (ROS) and inhibited the apoptosis induced by zinc deficiency. In addition, it also reversed the inhibitory effects of dihydrotestosterone (DHT) infiltration. Moreover, the ZnMOF-MN treatment has been proved to accelerate wound healing and increase hair follicles in wound healing models, and improved the hair regrowth in AGA animal models. Enhanced capillary density and cell proliferation observed in the CD31+ and Ki67+ staining of ZnMOF-MN group in both animal models also suggested that ZnMOF can facilitate angiogenesis and promote cell proliferation in the skin, respectively. Conclusion: The ZnMOF-MN treatment is a comprehensive solution with excellent therapeutic efficacy and patient-friendly features for promoting hair growth under various clinical conditions.


Assuntos
Curcumina , Camundongos , Animais , Curcumina/farmacologia , Curcumina/uso terapêutico , Zinco/farmacologia , Antígeno Ki-67 , Camundongos Endogâmicos C57BL , Cabelo , Alopecia/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Compostos Orgânicos/farmacologia
20.
Signal Transduct Target Ther ; 8(1): 367, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37752146

RESUMO

Lymph nodes (LNs) are important hubs for metastatic cell arrest and growth, immune modulation, and secondary dissemination to distant sites through a series of mechanisms, and it has been proved that lymph node metastasis (LNM) is an essential prognostic indicator in many different types of cancer. Therefore, it is important for oncologists to understand the mechanisms of tumor cells to metastasize to LNs, as well as how LNM affects the prognosis and therapy of patients with cancer in order to provide patients with accurate disease assessment and effective treatment strategies. In recent years, with the updates in both basic and clinical studies on LNM and the application of advanced medical technologies, much progress has been made in the understanding of the mechanisms of LNM and the strategies for diagnosis and treatment of LNM. In this review, current knowledge of the anatomical and physiological characteristics of LNs, as well as the molecular mechanisms of LNM, are described. The clinical significance of LNM in different anatomical sites is summarized, including the roles of LNM playing in staging, prognostic prediction, and treatment selection for patients with various types of cancers. And the novel exploration and academic disputes of strategies for recognition, diagnosis, and therapeutic interventions of metastatic LNs are also discussed.


Assuntos
Relevância Clínica , Linfonodos , Humanos , Metástase Linfática
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