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1.
Proc Natl Acad Sci U S A ; 120(14): e2216006120, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36972460

RESUMO

Intrinsically disordered proteins (IDPs) SAID1/2 are hypothetic dentin sialophosphoprotein-like proteins, but their true functions are unknown. Here, we identified SAID1/2 as negative regulators of SERRATE (SE), a core factor in miRNA biogenesis complex (microprocessor). Loss-of-function double mutants of said1; said2 caused pleiotropic developmental defects and thousands of differentially expressed genes that partially overlapped with those in se. said1; said2 also displayed increased assembly of microprocessor and elevated accumulation of microRNAs (miRNAs). Mechanistically, SAID1/2 promote pre-mRNA processing 4 kinase A-mediated phosphorylation of SE, causing its degradation in vivo. Unexpectedly, SAID1/2 have strong binding affinity to hairpin-structured pri-miRNAs and can sequester them from SE. Moreover, SAID1/2 directly inhibit pri-miRNA processing by microprocessor in vitro. Whereas SAID1/2 did not impact SE subcellular compartmentation, the proteins themselves exhibited liquid-liquid phase condensation that is nucleated on SE. Thus, we propose that SAID1/2 reduce miRNA production through hijacking pri-miRNAs to prevent microprocessor activity while promoting SE phosphorylation and its destabilization in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas Intrinsicamente Desordenadas , MicroRNAs , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a RNA/metabolismo , Processamento Pós-Transcricional do RNA , MicroRNAs/metabolismo , Ribonuclease III/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Biochem Biophys Res Commun ; 711: 149909, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38615573

RESUMO

RNA analysis has shown great value in forensic science, such as body fluids and tissue identification, postmortem interval estimation, biological age prediction, etc. Currently, most RNA follow-up experiments involve reverse transcription (RT) procedures. It has been shown that the RT step is variable and has a greater impact on subsequent data analysis, especially for forensic trace samples. However, the pattern of variation between different RNA template inputs and complementary DNA (cDNA) yield is unclear. In this study, a series of 2-fold gradient dilutions of RNA standards (1 µg/µL - 0.24 ng/µL) and forensic samples (including blood samples, saliva samples, bloodstains, and saliva stains) were reverse-transcribed using EasyQuick RT MasterMix. The obtained cDNA was quantified by droplet digital PCR (ddPCR) to assess the RT yield of the ACTB gene. The results showed that the 125 ng RNA template had the highest RT yield in a 10 µL RT reaction system with the selected kit. For all stain samples, the RT yield improved as the amount of RNA template input increased since RNA quantities were below 125 ng. As many commercialized reverse transcription kits using different kinds of enzymes are available for forensic RNA research, we recommend that systematic experiments should be performed in advance to determine the amount of RNA input at the optimum RT yield when using any kit for reverse transcription experiments.


Assuntos
RNA , Humanos , RNA/genética , RNA/análise , Transcrição Reversa , Saliva/metabolismo , Saliva/química , Genética Forense/métodos , Genética Forense/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Padrões de Referência , DNA Complementar/genética , Manchas de Sangue , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas
3.
Small ; 20(26): e2308861, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38372029

RESUMO

The anabolism of tumor cells can not only support their proliferation, but also endow them with a steady influx of exogenous nutrients. Therefore, consuming metabolic substrates or limiting access to energy supply can be an effective strategy to impede tumor growth. Herein, a novel treatment paradigm of starving-like therapy-triple energy-depleting therapy-is illustrated by glucose oxidase (GOx)/dc-IR825/sorafenib liposomes (termed GISLs), and such a triple energy-depleting therapy exhibits a more effective tumor-killing effect than conventional starvation therapy that only cuts off one of the energy supplies. Specifically, GOx can continuously consume glucose and generate toxic H2O2 in the tumor microenvironment (including tumor cells). After endocytosis, dc-IR825 (a near-infrared cyanine dye) can precisely target mitochondria and exert photodynamic and photothermal activities upon laser irradiation to destroy mitochondria. The anti-angiogenesis effect of sorafenib can further block energy and nutrition supply from blood. This work exemplifies a facile and safe method to exhaust the energy in a tumor from three aspects and starve the tumor to death and also highlights the importance of energy depletion in tumor treatment. It is hoped that this work will inspire the development of more advanced platforms that can combine multiple energy depletion therapies to realize more effective tumor treatment.


Assuntos
Glucose Oxidase , Lipossomos , Sorafenibe , Lipossomos/química , Humanos , Glucose Oxidase/metabolismo , Glucose Oxidase/química , Animais , Sorafenibe/farmacologia , Linhagem Celular Tumoral , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Metabolismo Energético , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/química , Indóis
4.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891876

RESUMO

Enterovirus A71 (EV-A71) is a major pathogen causing hand, foot, and mouth disease (HFMD) in children worldwide. It can lead to severe gastrointestinal, pulmonary, and neurological complications. The innate immune system, which rapidly detects pathogens via pathogen-associated molecular patterns or pathogen-encoded effectors, serves as the first defensive line against EV-A71 infection. Concurrently, the virus has developed various sophisticated strategies to evade host antiviral responses and establish productive infection. Thus, the virus-host interactions and conflicts, as well as the ability to govern biological events at this first line of defense, contribute significantly to the pathogenesis and outcomes of EV-A71 infection. In this review, we update recent progress on host innate immune responses to EV-A71 infection. In addition, we discuss the underlying strategies employed by EV-A71 to escape host innate immune responses. A better understanding of the interplay between EV-A71 and host innate immunity may unravel potential antiviral targets, as well as strategies that can improve patient outcomes.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Imunidade Inata , Humanos , Evasão da Resposta Imune/imunologia , Enterovirus Humano A/imunologia , Enterovirus Humano A/patogenicidade , Interações Hospedeiro-Patógeno/imunologia , Infecções por Enterovirus/imunologia , Infecções por Enterovirus/virologia , Animais , Doença de Mão, Pé e Boca/imunologia , Doença de Mão, Pé e Boca/virologia
5.
Int J Legal Med ; 137(6): 1853-1863, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37358650

RESUMO

Identification of body fluids is critical for crime scene reconstruction, and a source of investigation source of investigative leads. In recent years, microbial DNA analysis using sequencing and quantitative real-time polymerase chain reaction have been used to identify body fluids. However, these techniques are time-consuming, expensive, and require complex workflows. In this study, a new method for simultaneous detection of Streptococcus salivarius and Lactobacillus crispatus using polymerase chain reaction (PCR) in combination with a lateral flow dipstick (LFD) was developed to identify saliva and vaginal fluid in forensic samples. LFD results can be observed with the naked eye within 3 min with a sensitivity of 0.001 ng/µL DNA. The PCR-LFD assay was successfully used to detect S. salivarius and L. crispatus in saliva and vaginal fluid respectively, and showed negative results in blood, semen, nasal fluid, and skin. Moreover, saliva and vaginal fluid were detectable even at an extremely high mixing ratio of sample DNA (1:999). Saliva and vaginal fluid were identified in various mock forensic samples. These results indicate that saliva and vaginal fluid can be effectively detected by identifying S. salivarius and L. crispatus, respectively. Furthermore, we have shown that DNA samples used to identify saliva and vaginal fluid can also provide a complete short tandem repeat (STR) profile when used as source material for forensic STR profiling. In summary, our results suggest that PCR-LFD is a promising assay for rapid, simple, reliable, and efficient identification of body fluids.


Assuntos
Líquidos Corporais , Saliva , Feminino , Humanos , Saliva/microbiologia , Sêmen , DNA , Reação em Cadeia da Polimerase em Tempo Real , Bactérias , Genética Forense
6.
Nano Lett ; 21(16): 6990-6997, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34387505

RESUMO

We here demonstrate the multifunctional properties of atomically thin heterojunctions that are enabled by their strong interfacial interactions and their application toward self-powered sensors with unprecedented performance. Bonding between tin diselenide and graphene produces thermoelectric and mechanoelectric properties beyond the ability of either component. A record-breaking ZT of 2.43 originated from the synergistic combination of graphene's high carrier conductivity and SnSe2-mediated thermal conductivity lowering. Moreover, spatially varying interaction at the SnSe2/graphene interface produces stress localization that results in a novel 2D-crack-assisted strain sensing mechanism whose sensitivity (GF = 450) is superior to all other 2D materials. Finally, a graphene-assisted growth process permits the formation of high-quality heterojunctions directly on polymeric substrates for flexible and transparent sensors that achieve self-powered strain sensing from a small temperature gradient. Our work enhances the fundamental understanding of multifunctionality at the atomic scale and provides a route toward structural health monitoring through ubiquitous and smart devices.


Assuntos
Grafite , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Polímeros , Temperatura
7.
Angew Chem Int Ed Engl ; 61(40): e202206205, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-35962463

RESUMO

Ubiquitin (Ub)-like protein ISG15 (interferon-stimulated gene 15) regulates innate immunity and links with the evasion of host response by viruses such as SARS-CoV-2. Dissecting ISGylation pathways recently received increasing attention which can inform related disease interventions, but such studies necessitate the preparation and development of various ISG15 protein tools. Here, we find that the leader protease (Lbpro ) encoded by foot-and-mouth disease virus can promote ligation reactions between recombinant ISG15 and synthetic glycyl compounds, generating protein tools such as ISG15-propargylamide and ISG15-rhodamine110, which are needed for cellular proteomic studies of deISGylases, and the screening and evaluation of inhibitors against SARS-CoV-2 papain-like protease (PLpro). Furthermore, this strategy can be also used to load ISG15 onto the lysine of a synthetic peptide through an isopeptide bond, and prepare Ub and NEDD8 (ubiquitin-like protein Nedd8) protein tools.


Assuntos
COVID-19 , Peptídeo Hidrolases , Animais , Catálise , Citocinas/metabolismo , Interferons , Lisina , Proteína NEDD8 , Peptídeo Hidrolases/metabolismo , Proteômica , SARS-CoV-2 , Ubiquitinas/química
8.
Gastrointest Endosc ; 94(1): 91-100.e2, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33359435

RESUMO

BACKGROUND AND AIMS: We sought to compare the efficacy and safety between endoscopic radiofrequency ablation (RFA) and stent placement alone in patients with unresectable extrahepatic biliary cancer (EBC). METHODS: In this randomized controlled trial, patients with locally advanced or metastatic cholangiocarcinoma (CCA) or ampullary cancer who were unsuitable for surgery were recruited from 3 tertiary centers. Eligible patients were randomly assigned to RFA plus plastic stent placement (RFA group) or plastic stent placement alone (stent placement alone group) in a 1:1 ratio. Both groups underwent 2 scheduled interventions with an interval of approximately 3 months. The primary outcome was overall survival (OS). RESULTS: Altogether, 174 participants completed the 2 index endoscopic interventions. No significant differences in baseline characteristics were noted between the 2 groups. The median OS was significantly higher in the RFA group (14.3 vs 9.2 months; hazard ratio, .488; 95% confidence interval, .351-.678; P < .001). A survival benefit was also shown in patients with CCA (13.3 vs 9.2 months; hazard ratio, .546; 95% confidence interval, .386-.771; P < .001). However, no significant between-group differences were found in jaundice control or stent patency duration. The postprocedural Karnofsky performance scores were significantly higher in the RFA group until 9 months (all P < .001). Adverse events were comparable between the 2 groups (27.6% vs 19.5%, P = .211), except for acute cholecystitis, which was more frequently observed in the RFA group (9 vs 0, P = .003). CONCLUSIONS: Compared with stent placement alone, additional RFA may improve OS and quality of life of patients with inoperable primary EBC who do not undergo systemic treatments. (Clinical trial registration number: NCT01844245.).


Assuntos
Ampola Hepatopancreática , Neoplasias dos Ductos Biliares , Ablação por Cateter , Neoplasias do Ducto Colédoco , Ablação por Radiofrequência , Ampola Hepatopancreática/cirurgia , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Humanos , Plásticos , Qualidade de Vida , Stents , Resultado do Tratamento
9.
J Nanobiotechnology ; 19(1): 275, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34503490

RESUMO

BACKGROUND: Skin injury and the resultant defects are common clinical problems, and usually lead to chronic skin ulcers and even life-threatening diseases. Copper, an essential trace element of human body, has been reported to promote the regeneration of skin by stimulating proliferation of endothelial cell and enhance angiogenesis. RESULTS: Herein, we have prepared a new donut-like metal-organic frameworks (MOF) of copper-nicotinic acid (CuNA) by a simple solvothermal reaction. The rough surface of CuNA is beneficial for loading/release basic fibroblast growth factor (bFGF). The CuNAs with/without bFGF are easily processed into a light-responsive composite hydrogel with GelMA, which not only show excellent mechanical properties, but also display superior biocompatibility, antibacterial ability and bioactivity. Moreover, in the in vivo full-thickness defect model of skin wound, the resultant CuNA-bFGF@GelMA hydrogels significantly accelerate the wound healing, by simultaneously inhibiting the inflammatory response, promoting the new blood vessels formation and the deposition of collagen and elastic fibers. CONCLUSIONS: Considering the superior biocompatibility, antibacterial ability and bioactivity, the CuNA and its composite light-responsive hydrogel system will be promising in the applications of skin and even other tissue regeneration.


Assuntos
Fator 2 de Crescimento de Fibroblastos/farmacologia , Hidrogéis/química , Estruturas Metalorgânicas/química , Pele/patologia , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Força Compressiva , Cobre/química , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Hidrogéis/farmacologia , Camundongos , Niacina/química , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia
10.
Dig Endosc ; 33(1): 179-189, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32249460

RESUMO

BACKGROUND: Endoscopic stenting to manage malignant hilar biliary obstruction has no consensus regarding the optimal stenting strategy. In this multicenter study, we compared transpapillary parallel-style bilateral metal stenting with bilateral plastic stenting, and evaluated short- and long-term outcomes. METHODS: We recruited 262 consecutive patients (Bismuth classification types II-IV) who underwent either bilateral metal or plastic stenting as primary therapy at four tertiary centers. To overcome selection bias, we performed 1:1 propensity score matching. Our primary outcome was overall survival. RESULTS: After propensity score matching, each group comprised 96 patients, with no significant differences in any baseline characteristics. The median survival was significantly longer in the metal stenting group than in the plastic stenting group (7.2 months [95% CI 6.0-8.5] vs. 4.1 months [95% CI 2.9-5.3]; P = 0.015). The clinical success rates were significantly higher in the metal stenting group than in the plastic stenting group (99.0% vs. 71.9%, respectively; P < 0.001), and lower post-procedure cholangitis incidence (7.3% vs. 26.0%; P < 0.001), longer median symptom-free stent patency (9.2 months [95% CI 7.6-10.6] vs. 4.8 months [95% CI 4.2-5.3]; P < 0.001), and fewer total interventions (1.3 ± 0.6 vs. 2.0 ± 1.4; P < 0.001). In multivariate Cox analysis of the overall survival, metal stenting (HR 0.589, P = 0.002), hilar cholangiocarcinoma (HR 0.419, P = 0.009), and adjuvant treatment (HR 0.596, P = 0.006) were independent predictors of death. CONCLUSIONS: Endoscopic therapy using bilateral metal stenting is superior to bilateral plastic stenting, with prolonged overall survival, higher clinical success, and longer stent patency in patients with advanced hilar biliary malignancies.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Colestase , Neoplasias dos Ductos Biliares/complicações , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/complicações , Colangiocarcinoma/cirurgia , Colangiopancreatografia Retrógrada Endoscópica , Colestase/etiologia , Colestase/cirurgia , Constrição Patológica , Drenagem , Humanos , Cuidados Paliativos , Plásticos , Stents , Resultado do Tratamento
11.
Drug Dev Ind Pharm ; 45(9): 1556-1564, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31271317

RESUMO

Objective: This study was aimed to develop DOX-TPP loaded acetal-PEG-PCCL micelles to improve the clinical efficacy of drug resistance tumor. Significance: Chemotherapy is one of the main treatments for breast cancer but is plagued by multidrug resistance (MDR). DOX-TPP-loaded micelles can enhance the specific concentration of drugs in the tumor and improve the efficacy and overcome MDR. Methods: In this study, DOX-TPP-loaded micelles based on acetal-PEG-PCCL were prepared and their physicochemical properties were characterized. The cellular uptake and ability to induce apoptosis of the micelles was confirmed by flow cytometry in MCF-7/ADR cells. In addition, cytotoxicity of the micelles was studied in MCF-7 cells and MCF-7/ADR cells. Confocal is used to study the subcellular distribution of DOX. Free DOX-TPP or DOX-TPP-loaded acetal-PEG-PCCL micelles were administered via intravenous injection in the tail vain for the biodistribution study in vivo. Results: The diameter of micelles was about 102.4 nm and their drug-loading efficiency is 61.8%. The structural characterization was confirmed by 1H NMR. The micelles exhibited better antitumor efficacy compared to free doxorubicin in MCF-7/ADR cells by MTT assay. The apoptotic rate and the cellular uptake of micelles were significantly higher than free DOX and DOX-TPP. Micelles can efficiently deliver mitochondria-targeting DOX-TPP to tumor cells. The result of bio-distribution showed that the micelles had stronger tumor infiltration ability than free drugs. Conclusions: In this study, mitochondriotropic DOX-TPP was conjugated to the nanocarrier acetal-PEG-PCCL via ionic interaction to form a polymer, which spontaneously formed spherical micelles. The cytotoxicity and cellular uptake of the micelles are superior to free DOX and exhibit mitochondrial targeting and passive tumor targeting, indicating that they have potential prospects.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Nanoconjugados/química , Compostos Organofosforados/administração & dosagem , Acetais/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacocinética , Composição de Medicamentos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7 , Micelas , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Compostos Organofosforados/química , Compostos Organofosforados/farmacocinética , Poliésteres/química , Polietilenoglicóis/química , Distribuição Tecidual
12.
Nanotechnology ; 25(20): 205604, 2014 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-24786109

RESUMO

Nitrogen-doped carbon dots (N-CDs) with a high quantum yield of 19.6% were prepared by calcining polyvinyl pyrrolidone (PVP, K-30), and then modified with 4,7,10-trioxa-1,13-tridecanediamine. The as-prepared N-CDs exhibited excitation-dependent and pH-sensitive photoluminescence. Transmission electron microscopy and Raman spectra demonstrated the graphitic structure of the N-CDs. Fourier transform infrared spectroscopy and x-ray diffraction studies revealed successful passivation and the presence of hydrophilic groups on the surface. Importantly, such modified quantum dots acted as good multicolor cell imaging probes due to their excellent fluorescent properties, low cytotoxicity and fine dispersity.


Assuntos
Carbono , Microscopia de Fluorescência , Nitrogênio , Povidona , Pontos Quânticos/química , Células HeLa , Humanos , Microscopia Eletrônica de Transmissão , Pontos Quânticos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Difração de Raios X
13.
Int J Pharm ; 663: 124581, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39137819

RESUMO

Cold tumors lack T cells infiltration and have low immunogenicity, resulting insufficient immunotherapy response. Therefore, how to realize the transformation from cold tumor to hot tumor is an urgent problem to be solved. Photodynamic therapy can induce immunogenic death of tumor cells (ICD) and activate T lymphocytes to produce tumor immune response. However, hypoxia in the cold tumor microenvironment limits the effectiveness of photodynamic therapy. So in this article, MET-HMME/CAT-HMME@Nlip as a functional co-delivery nanoliposomes was constructed based on overcoming the above problems. Firstly, the oxygen-deficient state could be improved by the following two ways, one is catalase loaded in CAT-HMME@Nlip can decompose high concentration hydrogen peroxide to produce oxygen, and the other is metformin loaded in MET-HMME@Nlip can decrease oxygen consumption by inhibiting of mitochondrial respiration. And then with the increase of substrate oxygen concentration, the sensitivity of photodynamic therapy can be greatly improved and the anti-tumor immune response by PDT-induced ICD can also be enhanced obviously. In addition, metformin could act as a small molecule immune checkpoint inhibitor to reduce the expression of PD-L1 on the surface of tumor cells, thereby effectively improving the specific killing ability of cytotoxic T cells to tumor cells which could not only erasing the primary tumor, but also inhibiting the growth of simulated distant tumors through the immune memory function. This study provides a new idea for improving the clinical treatment effect of hypoxic cold tumors, especially for tumors that could not benefit from immunotherapy due to low or no expression of PD-L1 protein on the surface of tumor cells.


Assuntos
Antígeno B7-H1 , Imunoterapia , Lipossomos , Metformina , Nanopartículas , Fotoquimioterapia , Microambiente Tumoral , Fotoquimioterapia/métodos , Animais , Metformina/administração & dosagem , Metformina/farmacologia , Imunoterapia/métodos , Microambiente Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral , Nanopartículas/administração & dosagem , Camundongos , Catalase/administração & dosagem , Humanos , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Inibidores de Checkpoint Imunológico/administração & dosagem , Inibidores de Checkpoint Imunológico/farmacologia , Feminino , Fármacos Fotossensibilizantes/administração & dosagem , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Hipóxia Tumoral/efeitos dos fármacos , Peróxido de Hidrogênio , Camundongos Endogâmicos BALB C
14.
Int J Nanomedicine ; 19: 4121-4136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736655

RESUMO

Purpose: This study aims to broaden the application of nano-contrast agents (NCAs) within the realm of the musculoskeletal system. It aims to introduce novel methods, strategies, and insights for the clinical management of ischemic muscle disorders, encompassing diagnosis, monitoring, evaluation, and therapeutic intervention. Methods: We developed a composite encapsulation technique employing O-carboxymethyl chitosan (OCMC) and liposome to encapsulate NCA-containing gold nanorods (GNRs) and perfluoropentane (PFP). This nanoscale contrast agent was thoroughly characterized for its basic physicochemical properties and performance. Its capabilities for in vivo and in vitro ultrasound imaging and photothermal imaging were authenticated, alongside a comprehensive biocompatibility assessment to ascertain its effects on microcirculatory perfusion in skeletal muscle using a murine model of hindlimb ischemia, and its potential to augment blood flow and facilitate recovery. Results: The engineered GNR@OCMC-liposome/PFP nanostructure exhibited an average size of 203.18±1.49 nm, characterized by size uniformity, regular morphology, and a good biocompatibility profile. In vitro assessments revealed NCA's potent photothermal response and its transformation into microbubbles (MBs) under near-infrared (NIR) irradiation, thereby enhancing ultrasonographic visibility. Animal studies demonstrated the nanostructure's efficacy in photothermal imaging at ischemic loci in mouse hindlimbs, where NIR irradiation induced rapid temperature increases and significantly increased blood circulation. Conclusion: The dual-modal ultrasound/photothermal NCA, encapsulating GNR and PFP within a composite shell-core architecture, was synthesized successfully. It demonstrated exceptional stability, biocompatibility, and phase transition efficiency. Importantly, it facilitates the encapsulation of PFP, enabling both enhanced ultrasound imaging and photothermal imaging following NIR light exposure. This advancement provides a critical step towards the integrated diagnosis and treatment of ischemic muscle diseases, signifying a pivotal development in nanomedicine for musculoskeletal therapeutics.


Assuntos
Meios de Contraste , Ouro , Isquemia , Músculo Esquelético , Nanotubos , Ultrassonografia , Animais , Ouro/química , Nanotubos/química , Meios de Contraste/química , Meios de Contraste/farmacologia , Camundongos , Isquemia/diagnóstico por imagem , Isquemia/terapia , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia/métodos , Membro Posterior/irrigação sanguínea , Fluorocarbonos/química , Fluorocarbonos/farmacologia , Lipossomos/química , Quitosana/química , Quitosana/farmacologia , Doenças Musculares/diagnóstico por imagem , Doenças Musculares/terapia , Terapia Fototérmica/métodos , Modelos Animais de Doenças , Humanos , Pentanos
15.
Proc Inst Mech Eng H ; 238(4): 455-460, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38480483

RESUMO

Synthetic bone models such as polyurethane (PU) foam are a well-established substitute to cadaveric bone for screw pull-out testing; however, little attention has been given to the effect of PU foam anisotropy on orthopaedic implant testing. Compressive and screw pull-out performance in three PU foam densities; 0.16 g/cm3 (PCF 10), 0.32 g/cm3 (PCF 20) and 0.64 g/cm3 (PCF 40) were performed in each of the X, Y or Z orientations. The maximum compressive force, stiffness in the linear region, maximum stress and modulus were determined for all compression tests. Pedicle screws were inserted and pulled out axially to determine maximum pull-out force, energy to failure and stiffness. One-way ANOVA and post hoc tests were used to compare outcome variables between PU foam densities and orientations, respectively. Compression tests demonstrated the maximum force was significantly different between all orientations for PCF 20 (X, Y and Z) while stiffness and maximum stress were different between X versus Y and X versus Z. Maximum pull-out force was significantly different between all orientations for PCF 10 foam. No significant differences were noted for other foam densities. There is potential for screw pull-out testing results to be significantly affected by orientation in lower density PU foams. It is recommended that a single, known orientation of the PU foam block be used for experimental testing.


Assuntos
Parafusos Pediculares , Humanos , Poliuretanos , Teste de Materiais , Fenômenos Mecânicos , Fenômenos Biomecânicos
16.
Sci Total Environ ; 917: 170541, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38290684

RESUMO

Microplastics (MPs) can co-occur widely with heavy metals in soil. This study intended to investigate the influences of the co-exposure of polyethylene MPs (0.5 %, w/w) and cadmium (Cd) in black soil on the Cd distribution, enzyme activities, and bacterial communities in both bulk soil and different sized soil aggregates (> 1, 0.50-1, 0.25-0.50, and < 0.25 mm aggregates) after a 90-day incubation. Our results showed that the existence of MPs increased the distributions of Cd in >1 mm and < 0.25 mm soil aggregates and decreased its distributions in 0.50-1 mm and 0.25-0.50 mm soil aggregates. About 12.15 %-17.65 % and 9.03 %-11.13 % of Cd were distributed in the exchangeable and oxidizable forms in bulk soil and various sized soil aggregates after the addition of MPs which were higher than those in the only Cd-treated soil (11.17 %-14.72 % and 8.66 %-10.43 %, respectively), while opposite tendency was found for Cd in the reducible form. Urease and ß-glucosidase activities in the Cd-treated soils were 1.14-1.18 and 1.07-1.31 times higher than those in the Cd-MPs treated soils. MPs disturbed soil bacterial community at phylum level and increased the bacteria richness in bulk soil. The levels of predicted functional genes which are linked to the biodegradation and metabolism of exogenous substances and soil C and N cycles were altered by the co-exposure of Cd and MPs. The findings of this study could help deepen our knowledge about the responses of soil properties, especially microbial community, to the co-occurrence of MPs and heavy metals in soil.


Assuntos
Metais Pesados , Poluentes do Solo , Microplásticos , Cádmio/análise , Plásticos , Solo , Polipropilenos , Poluentes do Solo/análise , Bactérias
17.
J Appl Biomater Funct Mater ; 22: 22808000241240296, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38509449

RESUMO

Joint replacements provide pain free movement for the injured or our aging population. Current prothesis mainly consist of hard metal on metal, or ceramic femoral head on ultra-high-molecular weight polyethylene (UHMWPE). In this study, a rodent fracture model was used to test the influence of wear debris from a high-performance polymer (polyimide MP-1™). Saline, MP-1™ Low Dose in Saline (1%), or MP-1 High Dose (2%) in Saline was injected directly into a standard closed unilateral femoral fracture in 12-week old Sprague Dawley rats (n = 25) for 1, 3 and 6 weeks. Endpoints included radiography, micro-computed tomography, mechanical testing and paraffin histology. No adverse effects from the wear particles were observed from the current study based on radiology, mechanical or histological data. Although the particles were present, histological analysis revealed a progression in healing between the Polyimide treated groups and the non-treated saline control groups over the duration of 1, 3, and 6 weeks, with no inhibition from the particles. The MP-1™ wear debris generated are larger than 1 µm thus are not able to be engulfed by macrophages and cause osteolysis. This family of polymers (polyimides) may be an ideal material to consider for articulating joints and other implants in the human body.


Assuntos
Consolidação da Fratura , Prótese de Quadril , Humanos , Animais , Ratos , Idoso , Microtomografia por Raio-X , Ratos Sprague-Dawley , Polietilenos/efeitos adversos , Macrófagos , Falha de Prótese , Prótese de Quadril/efeitos adversos
18.
Nanomedicine (Lond) ; 19(14): 1297-1311, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39046514

RESUMO

Aim: To develop a robust drug-delivery system using multi-arm amphiphilic block copolymers for enhanced efficacy in cancer therapy. Materials & methods: Two series of amphiphilic polymer micelles, PEG-b-PCLm and PEG-b-PCLm/TPGS, were synthesized. Doxorubicin (DOX) loading into the micelles was achieved via solvent dialysis. Results: The micelles displayed excellent biocompatibility, narrow size distribution, and uniform morphology. DOX-loaded micelles exhibited enhanced antitumor efficacy and increased drug accumulation at tumor sites compared with free DOX. Additionally, 4A-PEG47-b-PCL21/TPGS micelles effectively suppressed drug-resistant MCF-7/ADR cells. Conclusion: This study introduces a novel micelle formulation with exceptional serum stability and efficacy against drug resistance, promising for cancer therapy. It highlights innovative strategies for refining clinical translation and ensuring sustained efficacy and safety in vivo.


[Box: see text].


Assuntos
Doxorrubicina , Resistencia a Medicamentos Antineoplásicos , Micelas , Polietilenoglicóis , Doxorrubicina/farmacologia , Doxorrubicina/química , Humanos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Polietilenoglicóis/química , Animais , Células MCF-7 , Portadores de Fármacos/química , Camundongos , Vitamina E/química , Vitamina E/farmacologia , Feminino , Camundongos Endogâmicos BALB C , Polímeros/química , Camundongos Nus , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/administração & dosagem , Poliésteres/química , Sistemas de Liberação de Medicamentos , Sobrevivência Celular/efeitos dos fármacos
19.
Microbiol Spectr ; 12(4): e0248023, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38470485

RESUMO

Identification and the time since deposition (TsD) estimation of body fluid stains from a crime scene could provide valuable information for solving the cases and are always difficult for forensics. Microbial characteristics were considered as a promising biomarker to address the issues. However, changes in the microbiota may damage the specific characteristics of body fluids. Correspondingly, incorrect body fluid identification may result in inaccurate TsD estimation. The mutual influence is not well understood and limited the codetection. In the current study, saliva, semen, vaginal secretion, and menstrual blood samples were exposed to indoor conditions and collected at eight time points (from fresh to 30 days). High-throughput sequencing based on the 16S rRNA gene was performed to characterize the microbial communities. The results showed that a longer TsD could decrease the discrimination of different body fluid stains. However, the accuracies of identification still reached a quite high value even without knowing the TsD. Correspondingly, the mean absolute error (MAE) of TsD estimation significantly increased without distinguishing the types of body fluids. The predictive TsD of menstrual blood reached a quite low MAE (1.54 ± 0.39 d). In comparison, those of saliva (6.57 ± 1.17 d), semen (6.48 ± 1.33 d), and vaginal secretion (5.35 ± 1.11 d) needed to be further improved. The great effect of individual differences on these stains limited the TsD estimation accuracy. Overall, microbial characteristics allow for codetection of body fluid identification and TsD estimation, and body fluids should be identified before estimating TsD in microbiome-based stain analyses.IMPORTANCEEmerged evidences suggest microbial characteristics could be considered a promising tool for identification and time since deposition (TsD) estimation of body fluid stains. However, the two issues should be studied together due to a potential mutual influence. The current study provides the first evidence to understand the mutual influence and determines an optimal process for codetection of identification and TsD estimation for unknown stains for forensics. In addition, we involved aged stains into our study for identification of body fluid stains, rather than only using fresh stains like previous studies. This increased the predictive accuracy. We have preliminary verified that individual differences in microbiotas limited the predictive accuracy of TsD estimation for saliva, semen, and vaginal secretion. Microbial characteristics could provide an accurate TsD estimation for menstrual blood. Our study benefits the comprehensive understanding of microbiome-based stain analyses as an essential addition to previous studies.


Assuntos
Líquidos Corporais , Microbiota , Feminino , Humanos , Idoso , Corantes , RNA Ribossômico 16S/genética , Saliva
20.
Int J Biol Macromol ; 260(Pt 2): 129599, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246455

RESUMO

Addressing highly flammable and easily breeding bacteria property via environmentally friendly approach was critical for the large-scale application of lyocell fibers. Herein, a bio-based coating constructed by layer-by-layer deposition of adenosine triphosphate (ATP), chitosan (CS), and polyethyleneimine (PEI) was successfully fabricated to obtain excellent fire-resistant and antimicrobial lyocell fabrics (LBL/Lyocell). The resulted fabrics with add-on of 11.5 wt% achieved the limiting oxygen index (LOI) of 32.0 %. Meanwhile, compared with the pure lyocell fabrics, the peak of heat release rate (PHRR), total heat release (THR), and fire growth rate (FIGRA) of LBL/Lyocell fabrics decreased by 75.2 %, 61.0 % and 69.8 % in cone calorimetric test (CCT), respectively. By characterizing the gaseous products and solid residues, the presence of the ATP/CS/PEI coating could not only quickly form the dense expanded carbon layer by itself, but also promote the conversion of cellulose into thermal-stability residues, thus reducing the release of combustible substances during combustion and protecting the lyocell fabrics. In addition, LBL/Lyocell showed excellent antimicrobial properties with 99.99 % antibacterial rates against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). This bio-based coating was a promising candidate for efficiently flame-retardant cellulose fibers with excellent antibacteria.


Assuntos
Quitosana , Retardadores de Chama , Escherichia coli , Polietilenoimina , Staphylococcus aureus , Trifosfato de Adenosina , Antibacterianos/farmacologia , Celulose
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