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1.
J Mater Chem B ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38712564

RESUMEN

Although acceptor-donor-acceptor (A-D-A)-type molecules offer advantages in constructing NIR absorbing photothermal agents (PTAs) due to their strong intramolecular charge transfer and molecular planarity, their applications in photothermal therapy (PTT) of tumors remain insufficiently explored. In particular, the influence of ESP distribution on the optical properties of A-D-A photosensitizers has not been investigated. Herein, we analyze and compare the difference in ESP distribution between A-D-A-type small molecules and polymers to construct NIR absorbing PTAs with a high extinction coefficient (ε) and high photothermal conversion efficiency (PCE). The calculation results of density functional theory (DFT) indicate that the large ESP difference makes A-D-A-type small molecules superior to their polymer counterparts in realizing tight molecular packing and strong NIR absorbance. Among the as-prepared nanoparticles (NPs), Y6 NPs exhibited an obvious bathochromic shift of absorption peak from 711 nm to 822 nm, with the NIR-II emission extended to 1400 nm. Moreover, a high ε value of 5.69 L g-1 cm-1 and a PCE of 66.3% were attained, making Y6 NPs suitable for PTT. With a concentration of 100 µg mL-1, Y6 NPs in aqueous dispersion yielded a death rate of 93.4% for 4T1 cells upon 808 nm laser irradiation (1 W cm-2) for 10 min, which is comparable with the best results of recently reported PTT agents.

2.
BMC Med Educ ; 24(1): 405, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605345

RESUMEN

BACKGROUND: In medical imaging courses, due to the complexity of anatomical relationships, limited number of practical course hours and instructors, how to improve the teaching quality of practical skills and self-directed learning ability has always been a challenge for higher medical education. Artificial intelligence-assisted diagnostic (AISD) software based on volume data reconstruction (VDR) technique is gradually entering radiology. It converts two-dimensional images into three-dimensional images, and AI can assist in image diagnosis. However, the application of artificial intelligence in medical education is still in its early stages. The purpose of this study is to explore the application value of AISD software based on VDR technique in medical imaging practical teaching, and to provide a basis for improving medical imaging practical teaching. METHODS: Totally 41 students majoring in clinical medicine in 2017 were enrolled as the experiment group. AISD software based on VDR was used in practical teaching of medical imaging to display 3D images and mark lesions with AISD. Then annotations were provided and diagnostic suggestions were given. Also 43 students majoring in clinical medicine from 2016 were chosen as the control group, who were taught with the conventional film and multimedia teaching methods. The exam results and evaluation scales were compared statistically between groups. RESULTS: The total skill scores of the test group were significantly higher compared with the control group (84.51 ± 3.81 vs. 80.67 ± 5.43). The scores of computed tomography (CT) diagnosis (49.93 ± 3.59 vs. 46.60 ± 4.89) and magnetic resonance (MR) diagnosis (17.41 ± 1.00 vs. 16.93 ± 1.14) of the experiment group were both significantly higher. The scores of academic self-efficacy (82.17 ± 4.67) and self-directed learning ability (235.56 ± 13.50) of the group were significantly higher compared with the control group (78.93 ± 6.29, 226.35 ± 13.90). CONCLUSIONS: Applying AISD software based on VDR to medical imaging practice teaching can enable students to timely obtain AI annotated lesion information and 3D images, which may help improve their image reading skills and enhance their academic self-efficacy and self-directed learning abilities.


Asunto(s)
Inteligencia Artificial , Educación Médica , Humanos , Programas Informáticos , Aprendizaje , Tomografía Computarizada por Rayos X , Enseñanza
3.
Sci Total Environ ; 927: 172162, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38569954

RESUMEN

Acid mine drainage (AMD) induced by pyrite oxidation is a notorious and serious environmental problem, but the management of AMD in an economical and environmentally friendly way remains challenging. Here, lignin, a natural polymer and abundant waste, was employed as both a bactericide and passivator to prevent AMD formation. The addition of lignin to a mimic AMD formation system inoculated with Acidithiobacillus ferrooxidans at a lignin-to-pyrite weight ratio of 2.5: 10 reduced the combined abiotic and biotic oxidation of pyrite by 68.4 % (based on released SO42-). Morphological characterization of Acidithiobacillus ferrooxidans revealed that lignin could act on the cell surface and impair the cell integrity, disrupting its normal growth and preventing biotic oxidation of pyrite accordingly. Moreover, lignin can be used alone as a passivator to form a coating on the pyrite surface, reducing abiotic oxidation by 71.7 % (based on released SO42-). Through multiple technique analysis, it was proposed that the functional groups on lignin may coordinate with iron ions on pyrite, promoting its deposition on the surface. In addition, the inherent antioxidant activity of lignin may also be actively involved in the abatement of pyrite oxidation via the reduction of iron. Overall, this study offered a "treating waste with waste" strategy for preventing AMD formation at the source and opened a new avenue for the management of AMD.


Asunto(s)
Acidithiobacillus , Lignina , Minería , Acidithiobacillus/metabolismo , Hierro , Sulfuros , Oxidación-Reducción
4.
Plant Physiol Biochem ; 210: 108651, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38653098

RESUMEN

Sugar beet (Beta vulgaris L.) is an economically important sugar crop worldwide that is susceptible to sudden waterlogging stress during seedling cultivation, which poses a major threat to sugar beet development and production. Our understanding of the physiological basis of waterlogging tolerance in sugar beet is limited. To investigate the photosynthetic adaptation strategies of sugar beet to waterlogging stress conditions, the tolerant cultivar KUHN1260 (KU) and sensitive cultivar SV1433 (SV) were grown under waterlogging stress, and their photosynthetic function and reactive oxygen species (ROS) metabolism were assessed. Our results showed that waterlogging stress significantly reduced the photosynthetic pigment content, rubisco activity, and expression level of the photosynthetic enzyme genes SvRuBP, SvGAPDH, and SvPRK, gas exchange parameters, and chlorophyll fluorescence parameters, induced damage to the ultrastructure of the chloroplast of the two sugar beet cultivars, inhibited the photosynthetic carbon assimilation capacity of sugar beet leaves, damaged the structural stability of photosystem II (PSII), and disturbed the equilibrium between electrons at the acceptor and donor sides of PSII, which was the result of stomatal and non-stomatal limiting factors. Moreover, the level of ROS, H2O2, and O2▪-, antioxidant enzyme activity, and gene expression levels in the leaves of the two sugar beet cultivars increased over time under waterlogging stress; ROS accumulation was lower and antioxidant enzyme activities and gene expression levels were higher in the waterlogging-tolerant cultivar (KU) than the waterlogging-sensitive cultivar (SV). In sum, these responses in the more tolerant cultivars are associated with their resistance to waterlogging stress. Our findings will aid the breeding of waterlogging-tolerant sugar beet cultivars.


Asunto(s)
Beta vulgaris , Fotosíntesis , Especies Reactivas de Oxígeno , Beta vulgaris/fisiología , Beta vulgaris/metabolismo , Beta vulgaris/genética , Fotosíntesis/fisiología , Especies Reactivas de Oxígeno/metabolismo , Estrés Fisiológico , Hojas de la Planta/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Clorofila/metabolismo , Agua/metabolismo
5.
Plant Physiol Biochem ; 210: 108571, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38604011

RESUMEN

2-(2-Phenylethyl) chromone (PEC) and its derivatives are markers of agarwood formation and are also related to agarwood quality. However, the biosynthetic and regulatory mechanisms of PECs still remain mysterious. Several studies suggested that type III polyketide synthases (PKSs) contribute to PEC biosynthesis in Aquilaria sinensis. Furthermore, systematic studies on the evolution of PKSs in A. sinensis have rarely been reported. Herein, we comprehensively analyzed PKS genes from 12 plant genomes and characterized the AsPKSs in detail. A unique branch contained only AsPKS members was identified through evolutionary analysis, including AsPKS01 that was previously indicated to participate in PEC biosynthesis. AsPKS07 and AsPKS08, two tandem-duplicated genes of AsPKS01 and lacking orthologous genes in evolutionary models, were selected for their transient expression in the leaves of Nicotiana benthamiana. Subsequently, PECs were detected in the extracts of N. benthamiana leaves, suggesting that AsPKS07 and AsPKS08 promote PEC biosynthesis. The interaction between the promoters of AsPKS07, AsPKS08 and five basic leucine zippers (bZIPs) from the S subfamily indicated that their transcripts could be regulated by these transcription factors (TFs) and might further contribute to PECs biosynthesis in A. sinensis. Our findings provide valuable insights into the molecular evolution of the PKS gene family in A. sinensis and serve as a foundation for advancing PEC production through the bioengineering of gene clusters. Ultimately, this contribution is expected to shed light on the mechanism underlying agarwood formation.


Asunto(s)
Evolución Molecular , Thymelaeaceae , Thymelaeaceae/genética , Thymelaeaceae/enzimología , Filogenia , Familia de Multigenes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Nicotiana/genética , Nicotiana/enzimología , Nicotiana/metabolismo , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo
6.
Small Methods ; : e2301664, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38678518

RESUMEN

Multifunctional drug delivery systems (DDS) are in high demand for effectively targeting specific cells, necessitating excellent biocompatibility, precise release mechanisms, and sustained release capabilities. The hollow multishelled structure (HoMS) presents a promising solution, integrating structural and compositional design for efficient DDS development amidst complex cellular environments. Herein, starting from a Fe-based metal-organic framework (MOF), amorphous coordination polymers (CP) composited HoMS with controlled shell numbers are fabricated by balancing the rate of MOF decomposition and shell formation. Fe-CP HoMS loaded with DOX is utilized for synergistic chemotherapy and chemodynamic therapy, offering excellent responsive drug release capability (excellent pH-triggered drug release 82% within 72 h at pH 5.0 solution with doxorubicin (DOX) loading capacity of 284 mg g-1). In addition to its potent chemotherapy attributes, Fe-CP-HoMS possesses chemodynamic therapy potential by continuously catalyzing H2O2 to generate ·OH species within cancer cells, thus effectively inhibiting cancer cell proliferation. DOX@3S-Fe-CP-HoMS, at a concentration of 12.5 µg mL-1, demonstrates significant inhibitory effects on cancer cells while maintaining minimal cytotoxicity toward normal cells. It is envisioned that CP-HoMS could serve as an effective and biocompatible platform for the advancement of intelligent drug delivery systems in the realm of cancer therapy.

7.
Bioresour Technol ; 401: 130743, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38677388

RESUMEN

The cost of detoxification and neutralization poses certain challenges to the development of an economically viable lactic acid biorefinery with lignocellulosic biomass as feedstock. Herein, red mud, an alkaline waste, was explored as both a detoxifying agent and a neutralizer. Red mud treatment of lignocellulosic hydrolysate effectively removed the inhibitors generated in dilute acid pretreatment, improving the lactic acid productivity from 1.0 g/L·h-1 to 1.9 g/L·h-1 in later fermentation. In addition, red mud could replace CaCO3 as a neutralizer in lactic acid fermentation, which in turn enabled simultaneous bioleaching of valuable metals (Sc, Y, Nd, and Al) from red mud. The neutralization of alkali in red mud by acids retained in lignocellulosic hydrolysate and lactic acid produced from fermentation led to effective dealkalization, rendering a maximum alkali removal efficiency of 92.2 %. Overall, this study offered a win-win strategy for the valorization of both lignocellulosic biomass and red mud.


Asunto(s)
Ácido Láctico , Lignina , Lignina/química , Fermentación , Óxido de Aluminio/química , Biomasa , Hidrólisis , Residuos Industriales
8.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38474292

RESUMEN

E0703, a new steroidal compound optimized from estradiol, significantly increased cell proliferation and the survival rate of KM mice and beagles after ionizing radiation. In this study, we characterize its preclinical pharmacokinetics (PK) and predict its human PK using a physiologically based pharmacokinetic (PBPK) model. The preclinical PK of E0703 was studied in mice and Rhesus monkeys. Asian human clearance (CL) values for E0703 were predicted from various allometric methods. The human PK profiles of E0703 (30 mg) were predicted by the PBPK model in Gastro Plus software 9.8 (SimulationsPlus, Lancaster, CA, USA). Furthermore, tissue distribution and the human PK profiles of different administration dosages and forms were predicted. The 0.002 L/h of CL and 0.005 L of Vss in mice were calculated and optimized from observed PK data. The plasma exposure of E0703 was availably predicted by the CL using the simple allometry (SA) method. The plasma concentration-time profiles of other dosages (20 and 40 mg) and two oral administrations (30 mg) were well-fitted to the observed values. In addition, the PK profile of target organs for E0703 exhibited a higher peak concentration (Cmax) and AUC than plasma. The developed E0703-PBPK model, which is precisely applicable to multiple species, benefits from further clinical development to predict PK in humans.


Asunto(s)
Protectores contra Radiación , Ratones , Humanos , Animales , Perros , Modelos Biológicos , Administración Oral , Distribución Tisular , Farmacocinética
9.
J Voice ; 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38429118

RESUMEN

OBJECTIVE: To develop a novel Laryngopharyngeal Reflux Disease (LPRD) model in Bama pigs through endoscopic cricopharyngeal myotomy. METHODS: A total of eight 8-month-old Bama pigs were randomly assigned to either the control or surgery group. Prior to intervention, upper esophageal sphincter (UES) manometry and laryngopharyngeal Dx-pH monitoring were conducted to establish baseline physiological parameters for each pig. Subsequently, the surgery group underwent endoscopic cricopharyngeal myotomy, while the control group did not. Two weeks postintervention, these procedures were repeated to evaluate changes in UES contractility and the occurrence of reflux events. At week eight postsurgery, mucosal tissues from both groups were harvested for histological analysis. Hematoxylin and eosin (H&E) staining was used to assess inflammation, while transmission electron microscopy (TEM) examined alterations in intercellular spaces and desmosomes. RESULTS: The mean UES pressures in the control and surgery groups were 59 ± 9 mmHg and 68 ± 12 mmHg, respectively. In the surgery group, there was a significant decrease in UES pressure 2weeks after the operation compared to preoperative values (P = 0.005), whereas no significant change was observed in the control group (P = 0.488). Laryngopharyngeal reflux (LPR) was successfully induced in the surgery group as evidenced by reflux events with pH <5.0, which were not detected in the control group. HE staining revealed marked inflammatory cell infiltration and submucosal gland expansion in throat tissues of the surgery group Bama pigs. TEM further showed enlarged intercellular spaces and reduced desmosome numbers in the laryngopharyngeal epithelium compared to controls. CONCLUSION: Given analogous throat epithelial structures to humans, Bama pigs are an appropriate species for an LPRD animal model. Endoscopic cricopharyngeal myotomy effectively induces LPR and observable pathological changes in Bama pigs, providing a valuable platform for further research into LPRD pathophysiology.

10.
Nat Commun ; 15(1): 2292, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38480740

RESUMEN

Triple-negative breast cancer (TNBC) is a highly metastatic and heterogeneous type of breast cancer with poor outcomes. Precise, non-invasive methods for diagnosis, monitoring and prognosis of TNBC are particularly challenging due to a paucity of TNBC biomarkers. Glycans on extracellular vesicles (EVs) hold the promise as valuable biomarkers, but conventional methods for glycan analysis are not feasible in clinical practice. Here, we report that a lectin-based thermophoretic assay (EVLET) streamlines vibrating membrane filtration (VMF) and thermophoretic amplification, allowing for rapid, sensitive, selective and cost-effective EV glycan profiling in TNBC plasma. A pilot cohort study shows that the EV glycan signature reaches 91% accuracy for TNBC detection and 96% accuracy for longitudinal monitoring of TNBC therapeutic response. Moreover, we demonstrate the potential of EV glycan signature for predicting TNBC progression. Our EVLET system lays the foundation for non-invasive cancer management by EV glycans.


Asunto(s)
Vesículas Extracelulares , Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/terapia , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Biomarcadores de Tumor , Proyectos Piloto , Vesículas Extracelulares/patología , Polisacáridos
11.
J Ethnopharmacol ; 326: 117967, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38431111

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Psoraleae Fructus (PF), the dried fruit of Psoralea corylifolia L., is a commonly used traditional medicine that has contributed to the treatment of orthopedic diseases for thousands of years in China. However, recent PF-related liver injury reports have drawn widespread attention regarding its potential hepatotoxicity risks. AIM OF THE STUDY: This study was aimed to evaluate the long-term efficacy and chronic toxicity of PF using a 26-week administration experiment on rats in order to simulate the clinical usage situation. MATERIALS AND METHODS: The PF aqueous extract was consecutively administrated to rats daily at dosages of 0.7, 2.0, and 5.6 g/kg (equivalent to 1-8 times the clinical doses for humans) for as long as 26 weeks. Samples were collected after 13, 26, and 32 weeks (withdrawal for 6 weeks) since the first administration. The chronic toxicity of PF was evaluated by conventional toxicological methods, and the efficacy of PF was evaluated by osteogenic effects in the natural growth process. RESULTS: In our experiments, only the H group (5.6 g/kg) for 26-week PF treatment demonstrated liver or kidney injury, which the injuries were reversible after 6 weeks of withdrawal. Notably, the PF treatment beyond 13 weeks showed significant benefits for bone growth and development in rats, with a higher benefit-risk ratio in female rats. CONCLUSIONS: PF displayed a promising benefit-risk ratio in the treatment and prevention of osteoporosis, a disease that lacks effective medicine so far. This is the first study to elucidate the benefit-risk balance associated with clinical dosage and long-term use of PF, thereby providing valuable insights for rational clinical use and risk control of PF.


Asunto(s)
Medicamentos Herbarios Chinos , Fabaceae , Psoralea , Humanos , Ratas , Femenino , Animales , Frutas , Oportunidad Relativa , Hígado , Medicamentos Herbarios Chinos/toxicidad
12.
Math Biosci Eng ; 21(2): 2163-2188, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38454678

RESUMEN

An automatic recognizing system of white blood cells can assist hematologists in the diagnosis of many diseases, where accuracy and efficiency are paramount for computer-based systems. In this paper, we presented a new image processing system to recognize the five types of white blood cells in peripheral blood with marked improvement in efficiency when juxtaposed against mainstream methods. The prevailing deep learning segmentation solutions often utilize millions of parameters to extract high-level image features and neglect the incorporation of prior domain knowledge, which consequently consumes substantial computational resources and increases the risk of overfitting, especially when limited medical image samples are available for training. To address these challenges, we proposed a novel memory-efficient strategy that exploits graph structures derived from the images. Specifically, we introduced a lightweight superpixel-based graph neural network (GNN) and broke new ground by introducing superpixel metric learning to segment nucleus and cytoplasm. Remarkably, our proposed segmentation model superpixel metric graph neural network (SMGNN) achieved state of the art segmentation performance while utilizing at most 10000$ \times $ less than the parameters compared to existing approaches. The subsequent segmentation-based cell type classification processes showed satisfactory results that such automatic recognizing algorithms are accurate and efficient to execeute in hematological laboratories. Our code is publicly available at https://github.com/jyh6681/SPXL-GNN.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Procesamiento de Imagen Asistido por Computador/métodos , Leucocitos , Citoplasma
13.
Funct Plant Biol ; 512024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38354692

RESUMEN

Water stress (drought and waterlogging) leads to an imbalance in plant water distribution, disrupts cell homeostasis, and severely inhibits plant growth. Melatonin is a growth hormone that plants synthesise and has been shown to resist adversity in many plants. This review discusses the biosynthesis and metabolism of melatonin, as well as the changes in plant morphology and physiological mechanisms caused by the molecular defence process. Melatonin induces the expression of related genes in the process of plant photosynthesis under stress and protects the structural integrity of chloroplasts. Exogenous melatonin can maintain the dynamic balance of root ion exchange under waterlogging stress. Melatonin can repair mitochondria and alleviate damage caused by reactive oxygen species and reactive nitrogen species; and has a wide range of uses in the regulation of stress-specific genes and the activation of antioxidant enzyme genes. Melatonin improves the stability of membrane lipids in plant cells and maintains osmotic balance by regulating water channels. There is crosstalk between melatonin and other hormones, which jointly improve the ability of the root system to absorb water and breathe and promote plant growth. Briefly, as a multifunctional molecule, melatonin improves the tolerance of plants under water stress and promotes plant growth and development.


Asunto(s)
Melatonina , Melatonina/farmacología , Melatonina/genética , Melatonina/metabolismo , Deshidratación , Estrés Fisiológico , Antioxidantes/farmacología , Antioxidantes/metabolismo , Fotosíntesis , Plantas/genética
14.
Biochem Biophys Res Commun ; 702: 149627, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38340655

RESUMEN

Rupture of vulnerable plaque and secondary thrombosis caused by atherosclerosis are one of the main causes of acute cardiovascular and cerebrovascular events, and it is urgent to develop an in-situ, noninvasive, sensitive and targeted detection method at molecular level. We chose CD44, a specific receptor highly expressed on the surface of macrophages, as the target of the molecular probe, and modified the CD44 ligand HA onto the surface of Gd2O3@MSN, constructing the MRI imaging nanoprobe HA-Gd2O3@MSN for targeted recognition of atherosclerosis. The fundamental properties of HA-Gd2O3@MSN were initially investigated. The CCK-8, hemolysis, hematoxylin-eosin staining tests and blood biochemical assays confirmed that HA-Gd2O3@MSN possessed excellent biocompatibility. Laser confocal microscopy, cellular magnetic resonance imaging, flow cytometry and immunohistochemistry were used to verify that the nanoprobes had good targeting properties. The in vivo targeting performance of the nanoprobes was further validated by employing a rabbit atherosclerosis animal model. In summary, the synthesized HA-Gd2O3@MSN nanoprobes have excellent biocompatibility properties as well as good targeting properties. It could provide a new technical tool for early identification of atherosclerosis.


Asunto(s)
Aterosclerosis , Nanopartículas , Animales , Conejos , Ácido Hialurónico/química , Nanopartículas/química , Dióxido de Silicio/química , Línea Celular Tumoral , Aterosclerosis/diagnóstico por imagen
15.
Nat Commun ; 15(1): 1010, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38307902

RESUMEN

The reaction system of hydrogen peroxide (H2O2) catalyzed by nanozyme has a broad prospect in antibacterial treatment. However, the complex catalytic activities of nanozymes lead to multiple pathways reacting in parallel, causing uncertain antibacterial results. New approach to effectively regulate the multiple catalytic activities of nanozyme is in urgent need. Herein, Cu single site is modified on nanoceria with various catalytic activities, such as peroxidase-like activity (POD) and hydroxyl radical antioxidant capacity (HORAC). Benefiting from the interaction between coordinated Cu and CeO2 substrate, POD is enhanced while HORAC is inhibited, which is further confirmed by density functional theory (DFT) calculations. Cu-CeO2 + H2O2 system shows good antibacterial properties both in vitro and in vivo. In this work, the strategy based on the interaction between coordinated metal and carrier provides a general clue for optimizing the complex activities of nanozymes.


Asunto(s)
Antioxidantes , Oxidantes , Antioxidantes/farmacología , Cobre , Peróxido de Hidrógeno , Radical Hidroxilo , Antibacterianos/farmacología , Peroxidasa
16.
Antonie Van Leeuwenhoek ; 117(1): 44, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38413433

RESUMEN

Two fungal strains (K-2T and S1) were isolated from the deepest ocean sediment of the Challenger Deep located in the Mariana Trench. The internal transcribed spacer (ITS) gene sequences of the isolates K-2T and S1 differed from those of closely related species, such as Talaromyces assiutensis and T. trachyspermus. Phylogenetic analyses based on single and concatenated alignments of the genes, namely ITS, ß-tubulin (benA), calmodulin (cam), and the second-largest subunit fragment of the RNA polymerase II (rpb2) showed that the isolates K-2T and S1 were clustered together with other Talaromyces species, such as T. trachyspermus and T. assiutensis, as evidenced by the position on a terminal branch with high bootstrap support. They could also be distinguished from their closest relatives with valid published names via morphological and physiological characteristics, for example, growth at 4 °C-50 °C with a pH in the range of 1.5-12. Based on their phylogenetic, morphological, and physicochemical properties, the isolates K-2T and S1 represent a novel species in the genus Talaromyces, and the proposed name is Talaromyces sedimenticola sp. nov. The type strain is K-2T (= GDMCC 3.746T = JCM 39451T).


Asunto(s)
Ácidos Grasos , Talaromyces , Ácidos Grasos/química , Análisis de Secuencia de ADN , Filogenia , ARN Ribosómico 16S/genética , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética
18.
Adv Mater ; : e2313406, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38319004

RESUMEN

Single-atom nanozymes (SAzymes) showcase not only uniformly dispersed active sites but also meticulously engineered coordination structures. These intricate architectures bestow upon them an exceptional catalytic prowess, thereby captivating numerous minds and heralding a new era of possibilities in the biomedical landscape. Tuning the microstructure of SAzymes on the atomic scale is a key factor in designing targeted SAzymes with desirable functions. This review first discusses and summarizes three strategies for designing SAzymes and their impact on reactivity in biocatalysis. The effects of choices of carrier, different synthesis methods, coordination modulation of first/second shell, and the type and number of metal active centers on the enzyme-like catalytic activity are unraveled. Next, a first attempt is made to summarize the biological applications of SAzymes in tumor therapy, biosensing, antimicrobial, anti-inflammatory, and other biological applications from different mechanisms. Finally, how SAzymes are designed and regulated for further realization of diverse biological applications is reviewed and prospected. It is envisaged that the comprehensive review presented within this exegesis will furnish novel perspectives and profound revelations regarding the biomedical applications of SAzymes.

19.
Enzyme Microb Technol ; 176: 110411, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38377656

RESUMEN

A strain high-performance of esterase producing bacteria was screened from soil, which could selectively hydrolyze D-homoserine lactone from its racemate to achieve the resolution of L- homoserine lactone with more than 99% e.e. in 48% yield. L-homoserine lactone building block was then converted to L-α-amino-γ-bromobutyronic acid chiral blocks, which reacted with various nucleophilic reagent modules could to be applied to prepare L-γ- substituted α-amino acids such as L-selenomethionine, L-methionine, L-glufosinate and L-selenocystine. Its advantages included high selectivity of biocatalytic resolution reactions, high optical purity of products, racemic recycle of D-substrates and modular reaction, which simplified the production process of these products and highlighted the power of biological manufacturing.


Asunto(s)
4-Butirolactona/análogos & derivados , Lactonas , Aminoácidos , Biocatálisis , Serina
20.
Small ; : e2309067, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38189642

RESUMEN

To date, the excellent mass-catalytic activities of Pt single-atoms catalysts (Pt-SACs) toward hydrogen evolution reaction (HER) are categorically confirmed; however, their high current density performance remains a challenge for practical applications. Here, a binder-free approach is exemplified to fabricate self-standing superhydrophilic-superaerphobic Pt-SACs cathodes by directly anchoring Pt-SAs via Pt-Nx C4-x coordination bonds to the structurally-integrated 3D nitrogen-doped carbon tubes (N-CTs) array grid (denoted as Pt@N-CTs). The 3D Pt@N-CTs cathode with optimal Pt-SACs loading is capable of operating at a high current density of 1000 mA cm-2 with an ultralow overpotential of 157.9 mV with remarkable long-term stability over 11 days at 500 mA cm-2 . The 3D super-wettable free-standing Pt@N-CTs possess interconnected vertical and lateral N-CTs with hierarchical-sized open channels, which facilitates the mass transfer. The binder-free immobilization adding to the large surface area and 3D-interconnected open channels endow Pt@N-CTs cathodes with high accessible active sites, electrical conductivity, and structural stability that maximize the utilization efficiency of Pt-SAs to achieve ampere-level current density HER at low overpotentials.

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