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1.
Biomacromolecules ; 25(5): 3044-3054, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38662992

RESUMO

Photodynamic therapy (PDT) has demonstrated efficacy in eliminating local tumors, yet its effectiveness against metastasis is constrained. While immunotherapy has exhibited promise in a clinical context, its capacity to elicit significant systemic antitumor responses across diverse cancers is often limited by the insufficient activation of the host immune system. Consequently, the combination of PDT and immunotherapy has garnered considerable attention. In this study, we developed pH-responsive porphyrin-peptide nanosheets with tumor-targeting capabilities (PRGD) that were loaded with the IDO inhibitor NLG919 for a dual application involving PDT and immunotherapy (PRGD/NLG919). In vitro experiments revealed the heightened cellular uptake of PRGD/NLG919 nanosheets in tumor cells overexpressing αvß3 integrins. The pH-responsive PRGD/NLG919 nanosheets demonstrated remarkable singlet oxygen generation and photocytotoxicity in HeLa cells in an acidic tumor microenvironment. When treating HeLa cells with PRGD/NLG919 nanosheets followed by laser irradiation, a more robust adaptive immune response occurred, leading to a substantial proliferation of CD3+CD8+ T cells and CD3+CD4+ T cells compared to control groups. Our pH-responsive targeted PRGD/NLG919 nanosheets therefore represent a promising nanosystem for combination therapy, offering effective PDT and an enhanced host immune response.


Assuntos
Imunoterapia , Nanoestruturas , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Concentração de Íons de Hidrogênio , Imunoterapia/métodos , Nanoestruturas/química , Células HeLa , Animais , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Camundongos , Peptídeos/química , Peptídeos/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Porfirinas/química , Porfirinas/farmacologia , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/patologia , Imidazóis , Isoindóis
2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(3): 277-280, 2024 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-38863093

RESUMO

Objective: To achieve high throughput and high detection rate of circulating tumor cells (CTCs) in human peripheral blood, and to provide efficient and accurate early screening for cancer patients. Methods: A microfluidic chip with the integration of sorting, enrichment and detection was designed, and CTCs at the single cell level were detected by fluorescence detection system to obtain the number of CTCs in samples. Results: The peripheral blood samples after lysed red blood cells were used for 6 experiments. When the injection rate reached 0.2 mL/h, CTCs could reach the best detection rate of 78.6%, and the correlation coefficient within the group was above 0.8. Conclusion: CTCs detection system can achieve high detection rate and has good reliability, which can provide a reliable reference for clinical research in related fields.


Assuntos
Células Neoplásicas Circulantes , Humanos , Reprodutibilidade dos Testes , Separação Celular/instrumentação , Microfluídica , Técnicas Analíticas Microfluídicas
3.
Proc Biol Sci ; 289(1971): 20212645, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35291838

RESUMO

Teleosts are important models to study sex chromosomes and sex-determining (SD) genes because they present a variety of sex determination systems. Here, we used Nanopore and Hi-C technologies to generate a high-contiguity chromosome-level genome assembly of a YY southern catfish (Silurus meridionalis). The assembly is 750.0 Mb long, with contig N50 of 15.96 Mb and scaffold N50 of 27.22 Mb. We also sequenced and assembled an XY male genome with a size of 727.2 Mb and contig N50 of 13.69 Mb. We identified a candidate SD gene through comparisons to our previous assembly of an XX individual. By resequencing male and female pools, we characterized a 2.38 Mb sex-determining region (SDR) on Chr24. Analysis of read coverage and comparison of the X and Y chromosome sequences showed a Y specific insertion (approx. 500 kb) in the SDR which contained a male-specific duplicate of amhr2 (named amhr2y). amhr2y and amhr2 shared high-nucleotide identity (81.0%) in the coding region but extremely low identity in the promotor and intron regions. The exclusive expression in the male gonadal primordium and loss-of-function inducing male to female sex reversal confirmed the role of amhr2y in male sex determination. Our study provides a new example of amhr2 as the SD gene in fish and sheds light on the convergent evolution of the duplication of AMH/AMHR2 pathway members underlying the evolution of sex determination in different fish lineages.


Assuntos
Peixes-Gato , Animais , Peixes-Gato/genética , Mapeamento Cromossômico , Feminino , Genoma , Masculino , Filogenia , Cromossomos Sexuais , Processos de Determinação Sexual , Cromossomo X , Cromossomo Y/genética
4.
Artigo em Inglês | MEDLINE | ID: mdl-36574602

RESUMO

Photodynamic therapy (PDT) is a highly promising therapeutic modality for cancer treatment. The development of stimuli-responsive photosensitizer nanomaterials overcomes certain limitations in clinical PDT. Herein, we report the rational design of a highly sensitive PEGylated photosensitizer-peptide nanofiber (termed PHHPEG 6 NF) that selectively aggregates in the acidic tumor and lysosomal microenvironment. These nanofibers exhibit acid-induced enhanced singlet oxygen generation, cellular uptake, and PDT efficacy in vitro , as well as fast tumor accumulation, long-term tumor imaging capacity and effective PDT in vivo . Moreover, based on the prolonged presence of the fluorescent signal at the tumor site, we demonstrate that PHHPEG 6 NFs can also be applied for prognostic monitoring of the efficacy of PDT in vivo , which would potentially guide cancer treatment. Therefore, these multifunctional PHHPEG 6 NFs allow control over the entire PDT process, from visualization of photosensitizer accumulation, via actual PDT to the assessment of the efficacy of the treatment.

5.
Angew Chem Int Ed Engl ; 59(46): 20582-20588, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32687653

RESUMO

Inspired by the dynamic morphology control of molecular assemblies in biological systems, we have developed pH-responsive transformable peptide-based nanoparticles for photodynamic therapy (PDT) with prolonged tumor retention times. The self-assembled peptide-porphyrin nanoparticles transformed into nanofibers when exposed to the acidic tumor microenvironment, which was mainly driven by enhanced intermolecular hydrogen bond formation between the protonated molecules. The nanoparticle transformation into fibrils improved their singlet oxygen generation ability and enabled high accumulation and long-term retention at tumor sites. Strong fluorescent signals of these nanomaterials were detected in tumor tissue up to 7 days after administration. Moreover, the peptide assemblies exhibited excellent anti-tumor efficacy via PDT in vivo. This in situ fibrillar transformation strategy could be utilized to design effective stimuli-responsive biomaterials for long-term imaging and therapy.


Assuntos
Ácidos/química , Nanoestruturas/química , Peptídeos/química , Fotoquimioterapia/métodos , Humanos , Concentração de Íons de Hidrogênio , Fármacos Fotossensibilizantes/química , Porfirinas/química , Análise Espectral/métodos , Microambiente Tumoral
7.
Anal Bioanal Chem ; 410(27): 7019-7030, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30155705

RESUMO

A variety of automated sample-in-answer-out systems for in vitro molecular diagnostics have been presented and even commercialized. Although efficient in operation, they are incapable of quantifying targets, since quantitation based on analog analytical methods (via standard curve analysis) is complex, expensive, and challenging. To address this issue, herein, we describe an integrated sample-in-digital-answer-out (SIDAO) diagnostic system incorporating DNA extraction and digital recombinase polymerase amplification, which enables rapid and quantitative nucleic acid analysis from bodily fluids within a disposable cartridge. Inside the cartridge, reagents are pre-stored in sterilized tubes, with an automated pipetting module allowing facile liquid transfer. For digital analysis, we fabricate a simple, single-layer polydimethylsiloxane microfluidic device and develop a novel and simple sample compartmentalization strategy. Sample solution is partitioned into an array of 40,044 fL-volume microwells by sealing the microfluidic device through the application of mechanical pressure. The entire analysis is performed in a portable, fully automated instrument. We evaluate the quantitative capabilities of the system by analyzing Mycobacterium tuberculosis genomic DNA from both spiked saliva and serum samples, and demonstrate excellent analytical accuracy and specificity. This SIDAO system provides a promising diagnostic platform for quantitative nucleic acid testing at the point-of-care. Graphical abstract ᅟ.


Assuntos
DNA Bacteriano/análise , DNA Bacteriano/sangue , Dispositivos Lab-On-A-Chip , Mycobacterium tuberculosis/isolamento & purificação , Saliva/microbiologia , Tuberculose/diagnóstico , DNA Bacteriano/genética , Desenho de Equipamento , Fluorescência , Humanos , Dispositivos Lab-On-A-Chip/economia , Limite de Detecção , Mycobacterium tuberculosis/genética , Sistemas Automatizados de Assistência Junto ao Leito/economia , Fatores de Tempo , Tuberculose/sangue
8.
J Nanosci Nanotechnol ; 16(6): 6505-10, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27427744

RESUMO

Chinese Bama minipigs could be potential donors for the supply of xenografts because they are genetically stable, highly inbred, and inexpensive. However, porcine endogenous retrovirus (PERV) is commonly integrated in pig genomes and could cause a cross-species infection by xenotransplantation. For screening out the pigs with low copy numbers of PERV proviruses, we have developed a novel semiquantitative analysis approach based on magnetic nanoparticles (MNPs) and chemiluminescence (CL) for estimating relative copy numbers (RCNs) of PERV proviruses in Chinese Bama minipigs. The CL intensities of PERV proviruses and the housekeeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were respectively determined with this method, and the RCNs of PERV proviruses were calculated by the equation: RCN of PERV provirus = CL intensity of PERV provirus/CL intensity of GAPDH. The results showed that PERVs were integrated in the genomes of Bama minipigs at different copy numbers, and the copy numbers of PERV-C subtype were greatly low. Two Bama minipigs with low copy numbers of PERV proviruses were detected out and could be considered as xenograft donor candidates. Although only semiquantitation can be achieved, this approach has potential for screening out safe and suitable pig donors for xenotransplantation.


Assuntos
Retrovirus Endógenos/genética , Dosagem de Genes , Medições Luminescentes , Imãs/química , Nanopartículas , Provírus/genética , Porco Miniatura/virologia , Animais , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/química , Suínos
9.
J Nanosci Nanotechnol ; 15(2): 1789-92, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353733

RESUMO

Animal growth and development are complex and sophisticated biological metabolic processes, in which genes plays an important role. In this paper, we employed real-time quantitative PCR (RT-qPCR) to analyze the expression levels of hepatic GHR, JAK2 and IGF-I genes in 1, 30, 180 day of Bama minipig and Landrace with attempt to verify the correlation between the expression of these growth-associated genes and the dwarfism phenotype of Bama minipig. The results showed that the expression levels of these 3 genes in Bama minipigs were down-regulated expressed from 1 day to 30 day, and which was up-regulated expressed in Landrace. The expression levels of the 3 genes on 1, 30, 180 day were prominently higher in Landrace than in Bama minipigs. The significant differences of the 3 genes expression levels on 1 day between this two breeds indicate that different expressions of these genes might occur before birth. It is speculated that the down-regulated expression of the 3 genes may have a close correlation with the dwarfism phenotype of Bama minipig. More investigations in depth of this study is under progress with the help of biochip nanotechnology.


Assuntos
Nanismo/fisiopatologia , Fator de Crescimento Insulin-Like I/metabolismo , Janus Quinase 2/metabolismo , Fígado/metabolismo , Receptores da Somatotropina/metabolismo , Porco Miniatura/fisiologia , Envelhecimento/metabolismo , Animais , Regulação da Expressão Gênica no Desenvolvimento , Fenótipo , Especificidade da Espécie , Suínos
10.
J Nanosci Nanotechnol ; 15(8): 5597-604, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26369124

RESUMO

Porcine endogenous retrovirus (PERV) is commonly integrated in pig genomes, and could cause a cross-species infection by xenotransplantation. In this study, we developed a rapid and ultrasensitive approach for detection and subtyping of PERV provirus based on magnetic nanoparticles (MNPs) and chemiluminescence (CL). The carboxylated MNPs (CMNPs) were covalently coupled with aminated probes for capturing biotinylated target fragments of PERV, the product of polymerase chain reaction (PCR). Agarose gel electrophoresis analysis approved the reliability of biotinylated fragments. The MNPs composites were incubated with streptavidin-alkaline phosphatase (SA-ALP) and CL signal intensities were determined by subsequently adding 3-(2'-spiroadamantane)-4-methoxy-4-(3"-phosphoryloxy) phenyl-1,2-dioxetane (AMPPD). The optimal assay conditions of this approach were 1 mM for SA modification, 10 µM for probe modification, 55 (PERV), 54 (PERV-A), 50 (PERV-B), and 56 °C (PERV-C) for hybridization temperatures respectively, and 30 min for hybridization time. This approach was specific and highly sensitive, and the limit of detection (LOD) was 100 amol, which has the potential for screening out safe pig donors for xenotransplantation as well as to examine clinical samples from human patients treated with porcine xenotranplantation.


Assuntos
Técnicas Biossensoriais/instrumentação , Retrovirus Endógenos/classificação , Retrovirus Endógenos/isolamento & purificação , Medições Luminescentes/instrumentação , Nanopartículas de Magnetita/química , Desenho de Equipamento , Análise de Falha de Equipamento , Nanopartículas de Magnetita/ultraestrutura , Nanotecnologia/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
J Nanosci Nanotechnol ; 15(2): 1123-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353621

RESUMO

In this research, a novel method for relative fluorescent quantification of DNA based on Fe3O4@SiO2@Au gold-coated magnetic nanocomposites (GMNPs) and multiplex ligation- dependent probe amplification (MLPA) has been developed. With the help of self-assembly, seed-mediated growth and chemical reduction method, core-shell Fe3O4@SiO2@Au GMNPs were synthesized. Through modified streptavidin on the GMNPs surface, we obtained a bead chip which can capture the biotinylated probes. Then we designed MLPA probes which were tagged with biotin or Cy3 and target DNA on the basis of human APP gene sequence. The products from the thermostable DNA ligase induced ligation reactions and PCR amplifications were incubated with SA-GMNPs. After washing, magnetic separation, spotting, the fluorescent scanning results showed our method can be used for the relative quantitative analysis of the target DNA in the concentration range of 03004~0.5 µM.


Assuntos
DNA/análise , DNA/genética , Nanopartículas Metálicas/química , Microscopia de Fluorescência/instrumentação , Reação em Cadeia da Polimerase Multiplex/instrumentação , Nanocompostos/ultraestrutura , Sequência de Bases , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Ouro/química , Nanopartículas Metálicas/ultraestrutura , Microscopia de Fluorescência/métodos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Multiplex/métodos , Nanocompostos/química , Análise de Sequência de DNA/instrumentação , Análise de Sequência de DNA/métodos , Dióxido de Silício/química
12.
Phys Chem Chem Phys ; 16(16): 7481-90, 2014 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-24626959

RESUMO

The high oxidation activity of coinage metals (Cu, Ag and Au) has been widely applied in various important reactions, such as oxidation of carbon monoxide, alkenes or alcohols. The catalytic behavior of those inert metals has mostly been attributable to their size effect, the physical effect. In the present study, the chemical effects on their high oxidation activity have been investigated. We mechanistically examine the direct and oxidative dehydrogenation (partial oxidation) reactions of ethanol to acetaldehyde on a series of transition metals (groups 9, 10 and 11) with identical physical characteristics and varied chemical origins using density functional theory (DFT) calculations and electronic structure analyses at the GGA-PW91 level. The energetic results show that coinage metals have much lower activation energies and higher exothermicities for the oxidative dehydrogenation steps although they have higher energy for the direct dehydrogenation reaction. In the electronic structure analyses, coinage metals with saturated d bands can efficiently donate electrons to O* and OH*, or other electronegative adspecies, and better promote their p bands to higher energy levels. The negatively charged O* and OH* with high-lying p bands are responsible for lowering the energies in oxidative steps. The mechanistic understanding well explains the better oxidation activity of coinage metals and provides valuable information on their utilization in other useful applications, for example, the dehydrogenation process.

13.
J Nanosci Nanotechnol ; 14(1): 881-91, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24730305

RESUMO

Rabies is a fatal encephalomyelitis. Most cases occur in developing countries and are transmitted by dogs. The cell culture vaccines as associated with high cost; therefore, have not replaced the unsafe brain-derived vaccines. In the developing countries these brain-derived rabies vaccines still can be seen in action. Moreover, there will be a need for vaccines against rabies-related viruses against which classical vaccines are not always effective. The worldwide incidence of rabies and the inability of currently used vaccination strategies to provide highly potent and cost-effective therapy indicate the need for alternate control strategies. DNA vaccines have emerged as the safest vaccines and best remedy for complicated diseases like hepatitis, HIV, and rabies. A number of recombinant DNA vaccines are now being developed against several diseases such as AIDS and malaria. Therefore, it can be a valuable alternative for the production of cheaper rabies vaccines against its larger spectrum of viruses. In this review we report published data on DNA-based immunization with sequences encoding rabies with special reference to nanotechnology.


Assuntos
Nanocápsulas/administração & dosagem , Nanocápsulas/química , Raiva/prevenção & controle , Vacinas de DNA/administração & dosagem , Cristalização/métodos , Difusão , Composição de Medicamentos/métodos , Humanos , Nanocápsulas/ultraestrutura , Tamanho da Partícula , Vacina Antirrábica , Propriedades de Superfície
14.
J Nanosci Nanotechnol ; 14(5): 3337-42, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24734549

RESUMO

A rapid, ultrasensitive and economical Pseudorabies virus (PRV) detection system based on magnetic beads (MBs) and chemiluminescence was developed in this paper. The carboxyl functionalized MBs (MBs-COOH) were covalently coupled with aminated DNA probes for capturing PRV biotinylated amplicon, the product of polymerase chain reaction (PCR). Agarose gel electrophoresis analysis approved the reliability of biotinylated amplicon. The MBs composites were incubated with alkaline phosphatase labeled streptavidin (ALP-SA) and chemiluminescene was determined by subsequently adding 3-(2'-spiroadamantane)-4-methoxy-4-(3"-phosphoryloxy)phenyl-1,2-dioxetane (AMPPD). The optimal conditions of the PRV detection method were 10 microM for probe concentration, 50 degrees C for hybridization temperature and 30 min for hybridization time. The limit of detection (LOD) was as low as 100 amol/5 pM of amplicon which proved that this approach for PRV detection was ultrasensitive.


Assuntos
Herpesvirus Suídeo 1/isolamento & purificação , Magnetismo , Sequência de Bases , Primers do DNA , Sondas de DNA , Eletroforese em Gel de Ágar , Herpesvirus Suídeo 1/genética , Humanos , Limite de Detecção , Luminescência , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase
15.
J Nanosci Nanotechnol ; 14(7): 4886-90, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24757958

RESUMO

Pseudomonas aeruginosa is a common opportunistic pathogen in clinics. The species-specific ecfX gene of Pseudomonas aeruginosa has high specificity. In this experiment, we are intended to develop a new method for the detection of Pseudomonas aeruginosa based on magnetic enrichment and nested PCR, and the specific ecfX gene of Pseudomonas aeruginosa was used as the detection object. The genomic DNA of Pseudomonas aeruginosa was extracted using amino-modified magnetic nanoparticles (MNPs). The ecfX gene was amplified by nested PCR and the product of PCR was detected by agarose gel electrophoresis. The results showed that the optimal annealing temperature was 64 degrees C and 62 degrees C respectively in the first and the second rounds of PCR. The lowest concentration of Pseudomonas aeruginosa that could be detected was 10 cfu/mL. The method provides a reliable, timely and accurate technology for early detection of Pseudomonas aeruginosa. Furthermore, the method can shorten the procedure and time from DNA extraction to detection, which made automation more convenient.


Assuntos
Carga Bacteriana/métodos , DNA Bacteriano/genética , Separação Imunomagnética/métodos , Nanopartículas de Magnetita/química , Reação em Cadeia da Polimerase/métodos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , DNA Bacteriano/análise
16.
Sci Total Environ ; 921: 171105, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38402975

RESUMO

Compacted clay is employed as the buffer material for landfills, and multiple ions are dissolved in the leachate restricted by the compacted clay layer. The membrane efficiency is an important indicator to assess the barrier properties of the compacted clay layer and is measured through membrane tests. However, most membrane tests are currently conducted with a single solute solution, which does not reflect the mixed solution characteristics of leachates. To assess the membrane efficiency of compacted clay under mixed solution conditions, 13 membrane tests were conducted on a bentonite-amended soil using KCl-NaCl mixed solutions, KCl-CaCl2 mixed solutions, and KCl-AlCl3 mixed solutions with different mixing ratios at a total concentration of 20 mM. Nuclear magnetic resonance (NMR) tests were conducted on the soil specimen after the membrane tests to investigate the micromechanism of the membrane behavior under mixed solution conditions. Results indicate that the membrane efficiency increased with the mixing ratio of Na+ but decreased with the mixing ratio of Ca2+ or Al3+. In the 13 membrane tests, the lowest membrane efficiency was achieved when the specimen was tested with pure AlCl3 solution. The relationship between the membrane efficiency and mixing ratio was also investigated at the microscopic scale. As the ion valence increases, the diffuse double layer thickness is smaller and the proportion of macropores is larger, as verified by NMR tests.

17.
Bioinspir Biomim ; 19(4)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38718810

RESUMO

The spring-loaded inverted pendulum (SLIP) model is an effective model to capture the essential dynamics during human walking and/or running. However, most of the existing three-dimensional (3D) SLIP model does not explicitly account for human movement speed and frequency. To address this knowledge gap, this paper develops a new SLIP model, which includes a roller foot, massless spring, and concentrated mass. The governing equations-of-motion for the SLIP model during its double support phase are derived. It is noted that in the current formulation, the motion of the roller foot is prescribed; therefore, only the equations for the concentrated mass need to be solved. To yield model parameters leading to a periodic walking gait, a constrained optimization problem is formulated and solved using a gradient-based approach with a global search strategy. The optimization results show that when the attack angle ranges from 68° to 74°, the 3D SLIP model can yield a periodic walking gait with walking speeds varying from 0.5 to 2.0 m s-1. The predicted human walking data are also compared with published experimental data, showing reasonable accuracy.


Assuntos
Simulação por Computador , Marcha , Modelos Biológicos , Caminhada , Humanos , Caminhada/fisiologia , Marcha/fisiologia , Velocidade de Caminhada/fisiologia , Biomimética/métodos , Pé/fisiologia
18.
ACS Appl Mater Interfaces ; 16(7): 9466-9482, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38324654

RESUMO

The creation of a new metal-organic framework (MOF) with a hollow hierarchical porous structure has gained significant attention in the realm of enzyme immobilization. The present work employed a novel, facile, and effective combinatorial technique to synthesize modified MOF (N-PVP/HZIF-8) with a hierarchically porous core-shell structure, allowing for the preservation of the structural integrity of the encapsulated enzyme molecules. Scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, confocal laser scanning microscopy, and other characterization tools were used to fully explore the changes of morphological structure and surface properties in different stages of the preparation of immobilization enzyme CRL-N-PVP/HZIF-8, thus showing the superiority of N-PVP/HZIF-8 as an enzyme immobilization platform and the logic of the immobilization process on the carrier. Additionally, the maximum enzyme loading was 216.3 mg mL-1, the relative activity of CRL-N-PVP/HZIF-8 increased by 15 times compared with the CRL@ZIF-8 immobilized in situ, and exhibited quite good thermal, chemical, and operational stability. With a maximal conversion of 88.8%, CRL-N-PVP/HZIF-8 demonstrated good catalytic performance in the biosynthesis of phytosterol esters as a proof of concept. It is anticipated that this work will offer fresh concepts from several perspectives for the creation of MOF-based immobilized enzymes for biotechnological uses.


Assuntos
Estruturas Metalorgânicas , Zeolitas , Biocatálise , Zeolitas/química , Porosidade , Enzimas Imobilizadas/química , Catálise , Estruturas Metalorgânicas/química
19.
Front Neurol ; 15: 1366372, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770523

RESUMO

Migraine is a highly prevalent disease worldwide, imposing enormous clinical and economic burdens on individuals and societies. Current treatments exhibit limited efficacy and acceptability, highlighting the need for more effective and safety prophylactic approaches, including the use of nutraceuticals for migraine treatment. Migraine involves interactions within the central and peripheral nervous systems, with significant activation and sensitization of the trigeminovascular system (TVS) in pain generation and transmission. The condition is influenced by genetic predispositions and environmental factors, leading to altered sensory processing. The neuroinflammatory response is increasingly recognized as a key event underpinning the pathophysiology of migraine, involving a complex neuro-glio-vascular interplay. This interplay is partially mediated by neuropeptides such as calcitonin gene receptor peptide (CGRP), pituitary adenylate cyclase activating polypeptide (PACAP) and/or cortical spreading depression (CSD) and involves oxidative stress, mitochondrial dysfunction, nucleotide-binding domain-like receptor family pyrin domain containing-3 (NLRP3) inflammasome formation, activated microglia, and reactive astrocytes. Omega-3 polyunsaturated fatty acids (PUFAs), particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), crucial for the nervous system, mediate various physiological functions. Omega-3 PUFAs offer cardiovascular, neurological, and psychiatric benefits due to their potent anti-inflammatory, anti-nociceptive, antioxidant, and neuromodulatory properties, which modulate neuroinflammation, neurogenic inflammation, pain transmission, enhance mitochondrial stability, and mood regulation. Moreover, specialized pro-resolving mediators (SPMs), a class of PUFA-derived lipid mediators, regulate pro-inflammatory and resolution pathways, playing significant anti-inflammatory and neurological roles, which in turn may be beneficial in alleviating the symptomatology of migraine. Omega-3 PUFAs impact various neurobiological pathways and have demonstrated a lack of major adverse events, underscoring their multifaceted approach and safety in migraine management. Although not all omega-3 PUFAs trials have shown beneficial in reducing the symptomatology of migraine, further research is needed to fully establish their clinical efficacy and understand the precise molecular mechanisms underlying the effects of omega-3 PUFAs and PUFA-derived lipid mediators, SPMs on migraine pathophysiology and progression. This review highlights their potential in modulating brain functions, such as neuroimmunological effects, and suggests their promise as candidates for effective migraine prophylaxis.

20.
Theriogenology ; 224: 68-73, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38754201

RESUMO

With the rapid development of intensive animal husbandry in the livestock industry, large quantities of manure waste containing phytate phosphorus are being generated. Phytase can effectively solve the problem of high phosphorus pollution in the feces of monogastric animals. Enviropig, which produces phytase in the salivary glands and secretes the enzyme in the saliva, were first generated in 1999. However, phytase is easily inactivated during digestion. To address this problem, cleavage-resistant phytase transgenic pigs were generated using handmade cloning in this study. Transgene construction was improved and three cell lines carrying Cafp were obtained. In total, 810 blastocysts were generated and 712 good-quality were transferred into six recipients. Fourteen piglets were born, of which six survived after weaning. Polymerase chain reaction and sequencing results showed that seven (three live and four dead) of the fourteen piglets carried Cafp. Phytase activity in the saliva of the six live cloned pigs was tested at four months of age, and only one pig had 0.155 FTU/mL enzyme activity. The other five pigs may not have been activated in the transgenic parotid gland. Among all the transgenic pigs, the highest phosphorus digestion rate was 59.2% of intake, representing a 25.4% decrease in fecal emission compared to the average of controls. Immunohistochemical results on the three Cafp-positive pigs that died after six months of age showed that the transgene was only expressed in parotid glands, confirming tissue-specific gene expression. In conclusion, cleavage-resistant phytase transgenic pigs were successfully produced through handmade cloning. The cloned pigs offer a unique biological approach to managing phosphorus nutrition and environmental pollution in animal husbandry.


Assuntos
6-Fitase , Animais Geneticamente Modificados , Clonagem de Organismos , Animais , 6-Fitase/metabolismo , 6-Fitase/genética , Suínos/genética , Clonagem de Organismos/veterinária , Clonagem de Organismos/métodos , Fósforo/metabolismo
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