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1.
Front Bioeng Biotechnol ; 12: 1363742, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558788

RESUMO

In recent years, stem cells and their secretomes, notably exosomes, have received considerable attention in biomedical applications. Exosomes are cellular secretomes used for intercellular communication. They perform the function of intercellular messengers by facilitating the transport of proteins, lipids, nucleic acids, and therapeutic substances. Their biocompatibility, minimal immunogenicity, targetability, stability, and engineerable characteristics have additionally led to their application as drug delivery vehicles. The therapeutic efficacy of exosomes can be improved through surface modification employing functional molecules, including aptamers, antibodies, and peptides. Given their potential as targeted delivery vehicles to enhance the efficiency of treatment while minimizing adverse effects, exosomes exhibit considerable promise. Stem cells are considered advantageous sources of exosomes due to their distinctive characteristics, including regenerative and self-renewal capabilities, which make them well-suited for transplantation into injured tissues, hence promoting tissue regeneration. However, there are notable obstacles that need to be addressed, including immune rejection and ethical problems. Exosomes produced from stem cells have been thoroughly studied as a cell-free strategy that avoids many of the difficulties involved with cell-based therapy for tissue regeneration and cancer treatment. This review provides an in-depth summary and analysis of the existing knowledge regarding exosomes, including their engineering and cardiovascular disease (CVD) treatment applications.

2.
Ecotoxicol Environ Saf ; 272: 116065, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38330872

RESUMO

Bisphenol A (BPA) and its substitute bisphenol S (BPS) are desirable materials widely used in manufacturing plastic products but can pose carcinogenic risks to humans. A new conductive iron-based metal-organic framework (Fe-HHTP)-modified pencil graphite electrode (PGE) for electrochemically sensing BPA and BPS was prepared and fully characterized by SEM, TEM, FT-IR, XRD, and XPS. Results showed that the optimal conditions for preparing Fe-HHTP/PGE were a pH of 6.5, a Fe-HHTP concentration of 2 mg·mL-1, a deposition potential of 0 V, and a deposition time of 100 s. The Fe-HHTP/PGE prepared under such conditions harbored a significant electrocatalytic activity with a detection limit of 0.8 nM for BPA and 1.7 nM for BPS (S/N = 3). Correspondingly, the electrochemical response current was linearly correlated to BPA and BPS, ranging from 0.01 to 100 µM. Fe-HHTP/PGE also obtained satisfactory recoveries by 93.8-102.1% and 96.0-101.3% for detecting BPA and BPS in plastic food packaging samples. Our work has provided a novel electrochemical tool to simultaneously detect BPA and BPS in food packaging samples and environmental matrixes.


Assuntos
Grafite , Estruturas Metalorgânicas , Fenóis , Humanos , Grafite/química , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos Benzidrílicos/química , Eletrodos
3.
Sci Rep ; 13(1): 19409, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938596

RESUMO

This study aimed to assess the feasibility of using magnetic resonance imaging (MRI)-based Delta radiomics characteristics extrapolated from the Ax LAVA + C series to identify intermediary- and high-risk factors in patients with cervical cancer undergoing surgery following neoadjuvant chemoradiotherapy. A total of 157 patients were divided into two groups: those without any intermediary- or high-risk factors and those with one intermediary-risk factor (negative group; n = 75). Those with any high-risk factor or more than one intermediary-risk factor (positive group; n = 82). Radiomics characteristics were extracted using Ax-LAVA + C MRI sequences. The data was divided into training (n = 126) and test (n = 31) sets in an 8:2 ratio. The training set data features were selected using the Mann-Whitney U test and the Least Absolute Shrinkage and Selection Operator (LASSO) test. The best radiomics features were then analyzed to build a preoperative predictive radiomics model for predicting intermediary- and high-risk factors in cervical cancer. Three models-the clinical model, the radiomics model, and the combined clinic and radiomics model-were developed in this study utilizing the random forest Algorithm. The receiver operating characteristic (ROC) curve, decision curve analysis (DCA), accuracy, sensitivity, and specificity were used to assess the predictive efficacy and clinical benefits of each model. Three models were developed in this study to predict intermediary- and high-risk variables associated with postoperative pathology for patients who underwent surgery after receiving neoadjuvant radiation. In the training and test sets, the AUC values assessed using the clinical model, radiomics model, and combined clinical and radiomics models were 0.76 and 0.70, 0.88 and 0.86, and 0.91 and 0.89, respectively. The use of machine learning algorithms to analyze Delta Ax LAVA + C MRI radiomics features can aid in the prediction of intermediary- and high-risk factors in patients with cervical cancer receiving neoadjuvant therapy.


Assuntos
Terapia Neoadjuvante , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Algoritmos , Instituições de Assistência Ambulatorial , Fatores de Risco
4.
Viruses ; 15(10)2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37896905

RESUMO

Domestic cat hepadnavirus (DCH) is an infectious disease associated with chronic hepatitis in cats, which suggests a similarity with hepatitis B virus infections in humans. Since its first identification in Australia in 2018, DCH has been reported in several countries with varying prevalence rates, but its presence in Taiwan has yet to be investigated. In this study, we aimed to identify the presence and genetic diversity of DCH infections in Taiwan. Among the 71 samples tested, eight (11.27%) were positive for DCH. Of these positive cases, three cats had elevated levels of alanine transaminase (ALT) and aspartate transaminase (AST), suggesting an association between DCH infection and chronic hepatitis. Four DCH-positive samples were also tested for feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) coinfection. One sample (25%) was positive for FIV, whereas there was no positive sample for FeLV (0%). In addition, we performed whole genome sequencing on six samples to determine the viral genome sequences. Phylogenetic analyses identified a distinct lineage compared with previously reported sequences. This study highlights the importance of continuous surveillance of DCH and further research to elucidate the pathophysiology and transmission route of DCH.


Assuntos
Doenças do Gato , Hepadnaviridae , Vírus da Imunodeficiência Felina , Humanos , Animais , Gatos , Hepadnaviridae/genética , Filogenia , Taiwan/epidemiologia , Vírus da Imunodeficiência Felina/genética , Vírus da Leucemia Felina , Hepatite Crônica , Variação Genética , Doenças do Gato/epidemiologia
5.
Organogenesis ; 16(4): 113-125, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32799735

RESUMO

Bone defects or fractures generally heal in the absence of major interventions due to the high regenerative capacity of bone tissue. However, in situations of severe/large bone defects, these orchestrated regeneration mechanisms are impaired. With advances in modern medicine, natural and synthetic bio-scaffolds from bioceramics and polymers that support bone growth have emerged and gained intense research interest. In particular, scaffolds that recapitulate the molecular cues of extracellular signals, particularly growth factors, offer potential as therapeutic bone biomaterials. The current challenges for these therapies include the ability to engineer materials that mimic the biological and mechanical properties of the real bone tissue matrix, whilst simultaneously supporting bone vascularization. In this review, we discuss the very recent innovative strategies in bone biomaterial technology, including those of endogenous biomaterials and cell/drug delivery systems that promote bone regeneration. We present our understanding of their current value and efficacy, and the future perspectives for bone regenerative medicine.


Assuntos
Materiais Biocompatíveis , Regeneração Óssea , Osso e Ossos/fisiologia , Engenharia Tecidual/métodos , Alicerces Teciduais , Biomimética , Cerâmica/uso terapêutico , Sistemas de Liberação de Medicamentos , Matriz Extracelular , Humanos , Células-Tronco Mesenquimais/fisiologia , Polímeros/uso terapêutico , Medicina Regenerativa
6.
Mol Med Rep ; 21(4): 1881-1889, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32319611

RESUMO

Osteoarthritis (OA) is one of the most prevalent joint disorders globally. Patients suffering from OA are often obese and adiposity is linked to chronic inflammation. In the present study, the potential of using exosomes isolated from adipose­derived stem cells (ADSCs) as a therapeutic tool for reducing chronic inflammation and promoting chondrogenesis was investigated using patient­derived primary cells. First, it was tested whether patient­derived ADSCs could differentiate into chondrogenic and osteogenic lineages. The ADSCs were then used as a source of exosomes. It was found that exosomes isolated from ADSCs, when co­cultured with activated synovial fibroblasts, downregulated the expression of pro­inflammatory markers interleukin (IL)­6, NF­κB and tumor necrosis factor­α, while they upregulated the expression of the anti­inflammatory cytokine IL­10; without exosomes, the opposite observations were made. In addition, inflammation­inflicted oxidative stress was induced in vitro by stimulating chondrocytes with H2O2. Treatment with exosomes protected articular chondrocytes from H2O2­induced apoptosis. Furthermore, exosome treatment promoted chondrogenesis in periosteal cells and increased chondrogenic markers, including Collagen type II and ß­catenin; inhibition of Wnt/ß­catenin, using the antagonist ICG­001, prevented exosome­induced chondrogenesis. Periosteal cells treated with exosomes exhibited higher levels of microRNA (miR)­145 and miR­221. The upregulation of miR­145 and miR­221 was associated with the enhanced proliferation of periosteal cells and chondrogenic potential, respectively. The present study provided evidence in support for the use of patient­derived exosomes, produced from ADSCs, for potential chondrogenic regeneration and subsequent amelioration of osteoarthritis.


Assuntos
Tecido Adiposo/citologia , Condrogênese , Exossomos/metabolismo , Inflamação/patologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Regulação para Cima , Idoso , Diferenciação Celular , Movimento Celular , Condrócitos/metabolismo , Fibroblastos/metabolismo , Humanos , Macrófagos/metabolismo , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Membrana Sinovial/metabolismo , Regulação para Cima/genética
7.
J Chemother ; 32(2): 53-65, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31928332

RESUMO

Plants and natural compounds have been widely recognized to have potential for the prevention of cancer progression and as complementary or standalone treatments for cancer patients. The major benefits of natural compounds are their reduced toxicity compared to more aggressive and widely utilized cancer treatment approaches. Preclinical studies have led to the discovery of a number of natural anticancer compounds, including preparations of Vitex negundo L., green tea, mandarin peel oil, ursolic acid, curcumin and resveratrol. Although the in vitro data highlights the potential of these natural alternatives, their benefits in clinical cancer treatment remain less conclusive. In this review, we will discuss some of the recent advances in natural anticancer treatment discovery for the four most prominent global cancers, namely, breast, lung, prostate and skin metastases. As the exploration of natural therapeutics continues to expand, these substances have the potential to be utilized as preventative strategies and complimentary therapeutics. In some cases, they may have sufficient anti-tumor and anti-carcinogenic properties to function as standalone cancer treatments.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias/tratamento farmacológico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Metilação de DNA/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais , Neoplasias da Próstata/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico
8.
Virus Res ; 270: 197675, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31351879

RESUMO

Administration of oncolytic viruses (OVs) is an emerging anticancer strategy that exploits the lytic nature of viral replication to enhance the killing of malignant cells. OVs can be used as tools to directly induce cancer cell death and to trigger local and/or systemic immune responses to metastatic cancer in vivo. The effectiveness of OV therapy was initially highlighted by the clinical use of the genetically modified herpes virus, talimogene laherparepvec, for melanoma therapy. A number of OVs are now being evaluated as potential treatments for cancer in clinical trials. In spite of being engineered to specifically target tumor cells, the safety and off-target effects of OV therapy are a concern. The potential safety concerns of OVs are highlighted by current clinical trial criteria, which exclude individuals harbouring other viral infections and people who are immunocompromised. Despite the potential for adverse effects, clinical trials to date revealed relatively minimal adverse immune-related effects, such as fever. With advances in our understanding of virus replication cycles, several novel OVs have emerged. Reverse genetic systems have facilitated the insertion of anticancer genes into a range of OVs to further enhance their tumor-killing capacity. In this review, we highlight the recent advances in OV therapy for a range of human cancers in in vitro and in in vivo animal studies. We further discuss the future of OVs as a therapeutic strategy for a range of life-threatening cancers.


Assuntos
Neoplasias/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/genética , Animais , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Humanos , Melanoma/terapia , Terapia Viral Oncolítica/efeitos adversos , Terapia Viral Oncolítica/tendências , Vírus Oncolíticos/fisiologia , Genética Reversa , Replicação Viral
9.
J Zhejiang Univ Sci B ; 14(11): 961-72, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24190442

RESUMO

Orthotopic liver transplantation (OLT) is the only proven effective treatment for both end-stage and metabolic liver diseases. Hepatocyte transplantation is a promising alternative for OLT, but the lack of available donor livers has hampered its clinical application. Hepatocyte-like cells (HLCs) differentiated from many multi-potential stem cells can help repair damaged liver tissue. Yet almost suitable cells currently identified for human use are difficult to harvest and involve invasive procedures. Recently, a novel mesenchymal stem cell derived from human menstrual blood (MenSC) has been discovered and obtained easily and repeatedly. In this study, we examined whether the MenSCs are able to differentiate into functional HLCs in vitro. After three weeks of incubation in hepatogenic differentiation medium containing hepatocyte growth factor (HGF), fibroblast growth factor-4 (FGF-4), and oncostain M (OSM), cuboidal HLCs were observed, and cells also expressed hepatocyte-specific marker genes including albumin (ALB), α-fetoprotein (AFP), cytokeratin 18/19 (CK18/19), and cytochrome P450 1A1/3A4 (CYP1A1/3A4). Differentiated cells further demonstrated in vitro mature hepatocyte functions such as urea synthesis, glycogen storage, and indocyanine green (ICG) uptake. After intrasplenic transplantation into mice with 2/3 partial hepatectomy, the MenSC-derived HLCs were detected in recipient livers and expressed human ALB protein. We also showed that MenSC-derived HLC transplantation could restore the serum ALB level and significantly suppressed transaminase activity of liver injury animals. In conclusion, MenSCs may serve as an ideal, easily accessible source of material for tissue engineering and cell therapy of liver tissues.


Assuntos
Diferenciação Celular , Doença Hepática Terminal/terapia , Hepatócitos/citologia , Menstruação/sangue , Células-Tronco Mesenquimais/citologia , Animais , Separação Celular , Hepatócitos/transplante , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C
10.
Arch Pharm (Weinheim) ; 345(2): 101-11, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21956661

RESUMO

Four series of compounds containing an anthraquinone-linked moiety and symmetrical or asymmetrical aminoacyl residues in side chains at positions 1,4-, 1,5-, 2,6-, and 2,7- were synthesized and evaluated for their inhibitory effects toward telomerase and hTERT expression. Of these, only compound B11 showed selective inhibition of telomerase activity. Although it is not as competent as several of the anthraquinones we identified previously, nevertheless, the result is consistent with that the general structure moiety at the 1,5-position of diaminoanthraquinone-linked compound is important for the telomerase inhibitory activity. Interestingly, compounds A6, A8, C8, and D8 exhibited selective repressing activities toward hTERT expression and showed less effect toward proliferation of the treated cancer cells. Although it is not apparent which structure moiety is responsible for the telomerase repression effects of these compounds, they could be further developed as potential anti-tumor agents.


Assuntos
Antraquinonas/síntese química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Telomerase/antagonistas & inibidores , Acilação , Aminação , Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Relação Estrutura-Atividade
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