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1.
Int J Pharm ; : 124453, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39013531

RESUMO

Nanozymes, nanostructured materials emulating natural enzyme activities, exhibit potential in catalyzing reactive oxygen species (ROS) production for cancer treatment. By facilitating oxidative reactions, elevating ROS levels, and influencing the tumor microenvironment (TME), nanozymes foster the eradication of cancer cells. Noteworthy are their superior stability, ease of preservation, and cost-effectiveness compared to natural enzymes, rendering them invaluable for medical applications. This comprehensive review intricately explores the interplay between ROS and tumor therapy, with a focused examination of metal-based nanozyme strategies mitigating tumor hypoxia. It provides nuanced insights into diverse catalytic processes, mechanisms, and surface modifications of various metal nanozymes, shedding light on their role in intra-tumoral ROS generation and applications in antioxidant therapy. The review concludes by delineating specific potential prospects and challenges associated with the burgeoning use of metal nanozymes in future tumor therapies.

2.
Int J Mol Sci ; 25(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39000395

RESUMO

As a widely distributed plant in Northeast China, Carex meyeriana Kunth (CMK) is generally considered to have antibacterial properties; however, there is a lack of scientific evidence for this. Therefore, we investigated the chemical composition of CMK extract and its effect against C. albicans. A total of 105 compounds were identified in the alcohol extracts of CMK by UPLC-Q-TOF-MS. Most were flavonoids, with Luteolin being the most represented. Among them, 19 compounds are found in the C. albicans lysates. After treatment with CMK ethanol extract, a significant reduction in the number of C. albicans colonies was observed in a vaginal douche solution from day 5 (p < 0.05). Furthermore, the CMK extract can reduce the number of C. albicans spores. The levels of IL-4, IL-6, IL-10, IL-1ß, and TNF-α in vaginal tissues all exhibited a significant decrease (p < 0.05) compared to those in the model group as determined by ELISA. The results of HE staining showed that CMK extract can eliminate vaginal mucosa inflammation. CMK adjusts the vaginal mucosa cells by targeting twenty-six different metabolites and five specific metabolic pathways in order to effectively eliminate inflammation. Simultaneously, the CMK regulates twenty-three types of metabolites and six metabolic pathways against C. albicans infection. So, CMK strongly inhibits the growth of C. albicans and significantly reduces vaginal inflammation, making it a promising candidate for treating C. albicans infection.


Assuntos
Antifúngicos , Candida albicans , Extratos Vegetais , Vagina , Candida albicans/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Feminino , Antifúngicos/farmacologia , Antifúngicos/química , Vagina/microbiologia , Vagina/efeitos dos fármacos , Animais , Citocinas/metabolismo , Humanos , Camundongos
3.
Ageing Res Rev ; 99: 102383, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38955264

RESUMO

Globally, Alzheimer's disease (AD) is the most widespread chronic neurodegenerative disorder, leading to cognitive impairment, such as aphasia and agnosia, as well as mental symptoms, like behavioral abnormalities, that place a heavy psychological and financial burden on the families of the afflicted. Unfortunately, no particular medications exist to treat AD, as the current treatments only impede its progression.The link between AD and type 2 diabetes (T2D) has been increasingly revealed by research; the danger of developing both AD and T2D rises exponentially with age, with T2D being especially prone to AD. This has propelled researchers to investigate the mechanism(s) underlying this connection. A critical review of the relationship between insulin resistance, Aß, oxidative stress, mitochondrial hypothesis, abnormal phosphorylation of Tau protein, inflammatory response, high blood glucose levels, neurotransmitters and signaling pathways, vascular issues in AD and diabetes, and the similarities between the two diseases, is presented in this review. Grasping the essential mechanisms behind this detrimental interaction may offer chances to devise successful therapeutic strategies.

4.
Acta Pharmacol Sin ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987389

RESUMO

Influenza A virus (IAV) is a widespread pathogen that poses a significant threat to human health, causing pandemics with high mortality and pathogenicity. Given the emergence of increasingly drug-resistant strains of IAV, currently available antiviral drugs have been reported to be inadequate to meet clinical demands. Therefore, continuous exploration of safe, effective and broad-spectrum antiviral medications is urgently required. Here, we found that the small molecule compound J1 exhibited low toxicity both in vitro and in vivo. Moreover, J1 exhibits broad-spectrum antiviral activity against enveloped viruses, including IAV, respiratory syncytial virus (RSV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human coronavirus OC43 (HCoV-OC43), herpes simplex virus type 1 (HSV-1) and HSV-2. In this study, we explored the inhibitory effects and mechanism of action of J1 on IAV in vivo and in vitro. The results showed that J1 inhibited infection by IAV strains, including H1N1, H7N9, H5N1 and H3N2, as well as by oseltamivir-resistant strains. Mechanistic studies have shown that J1 blocks IAV infection mainly through specific interactions with the influenza virus hemagglutinin HA2 subunit, thereby blocking membrane fusion. BALB/c mice were used to establish a model of acute lung injury (ALI) induced by IAV. Treatment with J1 increased survival rates and reduced viral titers, lung index and lung inflammatory damage in virus-infected mice. In conclusion, J1 possesses significant anti-IAV effects in vitro and in vivo, providing insights into the development of broad-spectrum antivirals against future pandemics.

5.
Sci Total Environ ; : 174739, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39009142

RESUMO

The risk assessment of an expanding array of emerging contaminants in aquatic ecosystems and the establishment of water quality criteria rely on species sensitivity distribution (SSD), necessitating ample multi-trophic toxicity data. Computational methods, such as quantitative structure-activity relationship (QSAR), enable the prediction of specific toxicity data, thus mitigating the need for costly experimental testing and exposure risk assessment. In this study, robust QSAR models for four aquatic species (Rana pipiens, Crassostrea virginica, Asellus aquaticus, and Lepomis macrochirus) were developed using leave-one-out (LOO) screening variables and the partial least squares algorithm to predict toxicity data for paraquat, bisphenol A, and carbamazepine. These predicted data can be integrated with experimental data to construct SSD models and derive hazardous concentration for 5 % of species (HC5) for the criterion maximum concentration. The chronic water quality criterion for paraquat, bisphenol A, and carbamazepine were determined at 6.7, 11.1, and 3.5 µg/L, respectively. The QSAR-SSD approach presents a viable and cost-effective method for deriving water quality criteria for other emerging contaminants.

6.
Nano Lett ; 24(28): 8752-8762, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38953881

RESUMO

Acute methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is a common and serious lung infection with high morbidity and mortality rates. Due to the increasing antibiotic resistance, toxicity, and pathogenicity of MRSA, there is an urgent need to explore effective antibacterial strategies. In this study, we developed a dry powder inhalable formulation which is composed of porous microspheres prepared from poly(lactic-co-glycolic acid) (PLGA), internally loaded with indocyanine green (ICG)-modified, heat-resistant phages that we screened for their high efficacy against MRSA. This formulation can deliver therapeutic doses of ICG-modified active phages to the deep lung tissue infection sites, avoiding rapid clearance by alveolar macrophages. Combined with the synergistic treatment of phage therapy and photothermal therapy, the formulation demonstrates potent bactericidal effects in acute MRSA pneumonia. With its long-term stability at room temperature and inhalable characteristics, this formulation has the potential to be a promising drug for the clinical treatment of MRSA pneumonia.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Camundongos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Microesferas , Terapia Fototérmica , Pneumonia Estafilocócica/terapia , Terapia por Fagos/métodos , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Verde de Indocianina/uso terapêutico , Verde de Indocianina/administração & dosagem , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Administração por Inalação , Humanos , Bacteriófagos/química
7.
BMC Genomics ; 25(1): 681, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982349

RESUMO

Analyzing the genetic diversity and selection characteristics of sheep (Ovis aries) holds significant value in understanding their environmental adaptability, enhancing breeding efficiency, and achieving effective conservation and rational utilization of genetic resources. In this study, we utilized Illumina Ovine SNP 50 K BeadChip data from four indigenous sheep breeds from the southern margin of the Taklamakan Desert (Duolang sheep: n = 36, Hetian sheep: n = 74, Kunlun sheep: n = 27, Qira black sheep: n = 178) and three foreign meat sheep breeds (Poll Dorset sheep: n = 105, Suffolk sheep: n = 153, Texel sheep: n = 150) to investigate the population structure, genetic diversity, and genomic signals of positive selection within the indigenous sheep. According to the Principal component analysis (PCA), the Neighbor-Joining tree (NJ tree), and Admixture, we revealed distinct clustering patterns of these seven sheep breeds based on their geographical distribution. Then used Cross Population Extended Haplotype Homozygosity (XP-EHH), Fixation Index (FST), and Integrated Haplotype Score (iHS), we identified a collective set of 32 overlapping genes under positive selection across four indigenous sheep breeds. These genes are associated with wool follicle development and wool traits, desert environmental adaptability, disease resistance, reproduction, and high-altitude adaptability. This study reveals the population structure and genomic selection characteristics in the extreme desert environments of native sheep breeds from the southern edge of the Taklimakan Desert, providing new insights into the conservation and sustainable use of indigenous sheep genetic resources in extreme environments. Additionally, these findings offer valuable genetic resources for sheep and other mammals to adapt to global climate change.


Assuntos
Clima Desértico , Polimorfismo de Nucleotídeo Único , Seleção Genética , Animais , Ovinos/genética , Genética Populacional , Haplótipos , Variação Genética , Cruzamento
8.
Mar Genomics ; 76: 101112, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39009493

RESUMO

Dimethylsulfoniopropionate (DMSP) is a ubiquitous organosulfur molecule in marine environments with important roles in stress tolerance, global carbon and sulfur cycling, and chemotaxis. It is the main precursor of the climate active gas dimethyl sulfide (DMS), which is the greatest natural source of bio­sulfur transferred from ocean to atmosphere. Alteromonas sp. M12, a Gram-negative and aerobic bacterium, was isolated from the seawater samples collected from the Mariana Trench at the depth of 2500 m. Here, we report the complete genome sequence of strain M12 and its genomic characteristics to import and utilize DMSP. The genome of strain M12 contains one circular chromosome (5,012,782 bp) with the GC content of 40.88%. Alteromonas sp. M12 can grow with DMSP as a sole carbon source, and produced DMS with DMSP as a precursor. Genomic analysis showed that strain M12 contained a set of genes involved in the downstream steps of DMSP cleavage, but no known genes encoding DMSP transporters or DMSP lyases. The results indicated that this strain contained novel DMSP transport and cleavage genes in its genome which warrants further investigation. The import of DMSP into cells may be a strategy of strain M12 to adapt the hydrostatic pressure environment in the Mariana Trench, as DMSP can be used as a hydrostatic pressure protectant. This study sheds light on the catabolism of DMSP by deep-sea bacteria.


Assuntos
Alteromonas , Genoma Bacteriano , Compostos de Sulfônio , Compostos de Sulfônio/metabolismo , Alteromonas/genética , Água do Mar/microbiologia , Sulfetos
9.
Materials (Basel) ; 17(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38998443

RESUMO

Increased usage of selective laser sintering (SLS) for the production of end-use functional components has generated a requirement of developing new materials and process improvements to improve the applicability of this technique. This article discusses a novel process wherein carbon black was applied to the surface of TPU powder to reduce the laser reflectivity during the SLS process. The printing was carried out with a preheating temperature of 75 °C, laser energy density of 0.028 J/mm2, incorporating a 0.4 wt % addition of carbon black to the TPU powder, and controlling the powder layer thickness at 125 µm. The mixed powder, after printing, shows a reflectivity of 13.81%, accompanied by the highest average density of 1.09 g/cm3, hardness of 78 A, tensile strength of 7.9 MPa, and elongation at break was 364.9%. Compared to commercial TPU powder, which lacks the carbon black coating, the reflectance decreased by 1.78%, mechanical properties improved by 33.9%, and there was a notable reduction in the porosity of the sintered product.

10.
J Pharm Biomed Anal ; 249: 116339, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39024794

RESUMO

Codonopsis Radix (CR), a traditional tonic medicinal material in China, has been proven to possess a variety of bioactive functions. However, its chemical composition and in vivo metabolic pattern have not been fully elucidated. In this study, AB-8 macroporous resin column chromatography was employed for the enrichment of small molecular components in CR. Furthermore, a method combining ultra-performance liquid chromatography-quadrupole-orbitrap mass spectrometry with Acquire X intelligent data acquisition technology software was developed for the preliminary screening and identification of the chemical composition of CR in vitro and their metabolites in vivo. As a result, a total of 116 components were preliminarily characterized in the CR extract, including 28 polyacetylenes, 33 organic acids, 4 amino acids, 23 alkaloids, 9 phenylpropanoids, 6 terpenoids, 2 nucleosides, and 11 others. Additionally, a total of 84 compounds, including 37 prototype components and 47 metabolites, were identified in the plasma, urine, and feces of rats after oral administration of CR. Specifically, 11, 24, 19, 32, and 25 constituents were identified in the heart, liver, spleen, lung, and kidney, respectively. Of note, the lung and spleen are the organs with the highest distribution of CR compounds. These findings will serve as valuable data for future research on the correlation between the chemical composition and pharmacological effects of CR.

11.
Open Med (Wars) ; 19(1): 20240982, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38883336

RESUMO

Carnosine dipeptidase 1 (CNDP1), an enzyme integral to the hydrolysis of dipeptides containing histidine, plays an indispensable role in myriad physiological processes, including hydrolysis of proteins, maturation of specific biochemical functionalities within proteins, tissue regeneration, and regulation of cell cycle. However, the implications of CNDP1 in oncogenesis and its prognostic value are not yet fully elucidated. Initially, we procured the GSE40367 dataset from the Gene Expression Omnibus and established a protein-protein interaction network. Thereafter, we conducted functional and pathway enrichment analyses utilizing GO, KEGG, and GSEA. Moreover, we undertook an association analysis concerning the expression of CNDP1 with immune infiltration, along with survival analysis across various cancers and specifically in hepatocellular carcinoma (HCC). Our study uncovered a total of 2,248 differentially expressed genes, with a down-regulation of CNDP1 in HCC and other cancers. Our explorations into the relationship between CNDP1 and immune infiltration disclosed a negative correlation between CNDP1 expression and the presence of immune cells in HCC. Survival analyses revealed that diminished expression of CNDP1 correlates with an adverse prognosis in HCC and several other types of cancer. These observations intimate that CNDP1 holds promise as a novel prognostic biomarker for both pan-cancer and HCC.

12.
Mediators Inflamm ; 2024: 7709277, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38883967

RESUMO

Objective: At present, Alzheimer's disease (AD) lacks effective treatment means, and early diagnosis and intervention are the keys to treatment. Therefore, for mild cognitive impairment (MCI) and AD patients, blood sample analysis using the 4D nonstandard (label-free) proteomic in-depth quantitative analysis, looking for specific protein marker expression differences, is important. These marker levels change as AD progresses, and the analysis of these biomarkers changes with this method, which has the potential to show the degree of disease progression and can be used for the diagnosis and preventive treatment of MCI and AD. Materials and Methods: Patients were recruited according to the inclusion and exclusion criteria and divided into three groups according to scale scores. Elderly patients diagnosed with AD were selected as the AD group (n = 9). Patients diagnosed with MCI were classified into the MCI group (n = 10). Cognitively healthy elderly patients were included in the normal cognition control group (n = 10). Patients' blood samples were used for 4D label-free proteomic in-depth quantitative analysis to identify potential blood biomarkers. The sample size of each group was expanded (n = 30), and the selected biomarkers were verified by enzyme-linked immunosorbent assay (ELISA) to verify the accuracy of the proteomic prediction. Results: Six specific blood markers, namely, APOE, MMP9, UBR5, PLA2G7, STAT5B, and S100A8, were detected by 4D label-free proteomic quantitative analysis. These markers showed a statistically significant upregulation trend in the MCI and AD groups compared with the normal cognition control group (P < 0.05). ELISA results showed that the levels of these six proteins in the MCI group were significantly higher than those in the normal cognition control group, and the levels of these six proteins in the AD group were significantly higher than those in the MCI group (P < 0.05). Conclusion: The plasma levels of APOE, MMP9, UBR5, PLA2G7, STAT5B, and S100A8 in cognitively healthy elderly patients and patients with MCI and AD were significantly different and, more importantly, showed a trend of increasing expression. These results indicate that these six human plasma markers have important diagnostic and therapeutic potential in the identification of cognitive impairment and have value for in-depth research and clinical application.


Assuntos
Doença de Alzheimer , Biomarcadores , Disfunção Cognitiva , Proteômica , Humanos , Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico , Proteômica/métodos , Biomarcadores/sangue , Idoso , Feminino , Masculino , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Ensaio de Imunoadsorção Enzimática , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade
13.
J Dairy Sci ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38876213

RESUMO

High-yield dairy cows typically undergo intense cellular metabolism, leading to oxidative stress in their mammary tissues. Our study found that these high-yield cows had significantly elevated levels of hydrogen peroxide (H2O2), lipoperoxidase, and total antioxidant capacity in their blood, compared with ordinary cows. This increased oxidative stress is associated with heightened expression of genes such as GCLC, GCLM and SIRT1 and proteins such as SIRT1 in the mammary tissue of high-yield cows. MAC-T cells were stimulated with H2O2 at a concentration equal to the average H2O2 level in the serum of ethically high-yielding cows, as detected by an assay kit. Our observations revealed that short-term exposure (12 h) to H2O2 upregulated the expression of SIRT1 gene and protein. It also increased gene expression for SOD2, CAT, GCLC, GCLM, PGC-1α, and NQO1, elevated the phosphorylation of AMPK, and enhanced protein expression of PGC-1α, NQO1, Nrf2, and HO-1, while reducing the phosphorylation of NF-κB. Additionally, short-term H2O2 stimulation resulted in increased total antioxidant capacity, SOD, GSH, and CAT levels in the mammary epithelial cells of dairy cows. In contrast, prolonged exposure to H2O2 (24 h) yielded opposite results, indicating reduced antioxidant capacity. Further investigation showed that SIRT1 inhibitor (EX 527) could reverse the enhanced cellular antioxidant capacity triggered by short-term oxidative stress. However, it is crucial to note that while 12 h H2O2 stimulation improved antioxidant capacity, reactive oxygen species (ROS) and malondialdehyde (MDA) levels inside the cell gradually increased over time, suggesting greater damage under long-term stimulation. Conversely, the SIRT1 activator (SRT 2104) could reverse the reduced cellular antioxidant capacity caused by long-term oxidative stress and significantly inhibit the accumulation of ROS and MDA. Notably, SRT 2104 demonstrated similar effects in MAC-T cells during lactation. In summary, SIRT1 plays a crucial role in regulating the antioxidant capacity of mammary epithelial cells in dairy cows. This discovery provides valuable insights into the antioxidant mechanisms of mammary cells, which can serve as a theoretical foundation for future mammary health strategies.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38861428

RESUMO

The crux of effective out-of-distribution (OOD) detection lies in acquiring a robust in-distribution (ID) representation, distinct from OOD samples. While previous methods predominantly leaned on recognition-based techniques for this purpose, they often resulted in shortcut learning, lacking comprehensive representations. In our study, we conducted a comprehensive analysis, exploring distinct pretraining tasks and employing various OOD score functions. The results highlight that the feature representations pre-trained through reconstruction yield a notable enhancement and narrow the performance gap among various score functions. This suggests that even simple score functions can rival complex ones when leveraging reconstruction-based pretext tasks. Reconstruction-based pretext tasks adapt well to various score functions. As such, it holds promising potential for further expansion. Our OOD detection framework, MOODv2, employs the masked image modeling pretext task. Without bells and whistles, MOODv2 impressively enhances 14.30% AUROC to 95.68% on ImageNet and achieves 99.98% on CIFAR-10.

15.
Ecotoxicol Environ Saf ; 280: 116581, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38875820

RESUMO

Screening and prioritizing research on frequently detected mixture systems in the environment is of great significance, as conducting toxicity testing on all mixtures is impractical. Therefore, the frequent itemset mining (FIM) was introduced and applied in this paper to identify variables that commonly co-occur in a dataset. Based on the dataset of the quaternary ammonium compounds (QACs) in the water environment, the four frequent QAC mixture systems with detection rate ≥ 35 % were found, including [BDMM]+Cl--[BTMM]+Cl- (M1), [BDMM]+Cl--[BHMM]+Cl- (M2), [BTMM]+Cl- -[BHMM]+Cl- (M3), and [BDMM]+Cl--[BTMM]+Cl--[BHMM]+Cl- (M4). [BDMM]+Cl-, [BTMM]+Cl-, and [BHMM]+Cl- are benzyl dodecyl dimethyl ammonium chloride, benzyl tetradecyl dimethyl ammonium chloride, and benzyl hexadecyl dimethyl ammonium chloride, respectively. Then, the toxicity of the representative mixture rays and components for the four frequently detected mixture systems was tested using Vibrio qinghaiensis sp.-Q67 (Q67) as a luminescent indicator organism at 0.25 and 12 h. The toxicity of the mixtures was predicted using concentration addition (CA) and independent action (IA) models. It was shown that both the components and the representative mixture rays for the four frequently detected mixture systems exhibited obvious acute and chronic toxicity to Q67, and their median effective concentrations (EC50) were below 7 mg/L. Both CA and IA models predicted the toxicity of the four mixture systems well. However, the CA model had a better predictive ability for the toxicity of the M3 and M4 mixtures than IA at 12 h.


Assuntos
Compostos de Amônio Quaternário , Poluentes Químicos da Água , Compostos de Amônio Quaternário/toxicidade , Poluentes Químicos da Água/toxicidade , Monitoramento Ambiental/métodos , Testes de Toxicidade/métodos , Mineração de Dados
16.
Sci Data ; 11(1): 569, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830898

RESUMO

Large datasets of carbon dioxide, energy, and water fluxes were measured with the eddy-covariance (EC) technique, such as FLUXNET2015. These datasets are widely used to validate remote-sensing products and benchmark models. One of the major challenges in utilizing EC-flux data is determining the spatial extent to which measurements taken at individual EC towers reflect model-grid or remote sensing pixels. To minimize the potential biases caused by the footprint-to-target area mismatch, it is important to use flux datasets with awareness of the footprint. This study analyze the spatial representativeness of global EC measurements based on the open-source FLUXNET2015 data, using the published flux footprint model (SAFE-f). The calculated annual cumulative footprint climatology (ACFC) was overlaid on land cover and vegetation index maps to create a spatial representativeness dataset of global flux towers. The dataset includes the following components: (1) the ACFC contour (ACFCC) data and areas representing 50%, 60%, 70%, and 80% ACFCC of each site, (2) the proportion of each land cover type weighted by the 80% ACFC (ACFCW), (3) the semivariogram calculated using Normalized Difference Vegetation Index (NDVI) considering the 80% ACFCW, and (4) the sensor location bias (SLB) between the 80% ACFCW and designated areas (e.g. 80% ACFCC and window sizes) proxied by NDVI. Finally, we conducted a comprehensive evaluation of the representativeness of each site from three aspects: (1) the underlying surface cover, (2) the semivariogram, and (3) the SLB between 80% ACFCW and 80% ACFCC, and categorized them into 3 levels. The goal of creating this dataset is to provide data quality guidance for international researchers to effectively utilize the FLUXNET2015 dataset in the future.

17.
Front Microbiol ; 15: 1411537, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38832113

RESUMO

Lassa fever (LF), caused by Lassa virus (LASV), is one of the most dangerous diseases to public health. Homologous recombination (HR) is a basic genetic power driving biological evolution. However, as a negative-stranded RNA virus, it is unknown whether HR occurs between LASVs and its influence on the outbreak of LF. In this study, after analyzing 575 S and 433 L segments of LASV collected in Africa, we found that LASV can achieve HR in both of its segments. Interestingly, although the length of S segment is less than half of the L segment, the proportion of LASVs with S recombinants is significantly higher than that with L recombinants. These results suggest that HR may be a feature of LASV, which can be set by natural selection to produce beneficial or eliminate harmful mutations for the virus, so it plays a role in LASV evolution during the outbreak of LF.

18.
Anal Bioanal Chem ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38853180

RESUMO

Radix ginseng and Schisandra chinensis have been extensively documented in traditional Chinese medicine (TCM) for their potential efficacy in treating dementia. However, the precise mechanism of their therapeutic effects remains to be fully elucidated. In this study, air flow-assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI) and network pharmacology are used to investigate the pharmacodynamics and mechanism underlying the herbal combination consisting of Radix ginseng-Schisandra chinensis (RS) in a rodent model for Alzheimer's disease (AD). Brain histopathological findings suggested that RS attenuates hippocampal damage in AD mice, making this combination a potential AD treatment. Twenty-eight biomarkers were identified by spatial metabolomics analysis, which are intricately linked to neuroinflammation, neurotransmitter imbalance, energy deficiency, oxidative stress, and aberrant fatty acid metabolism in AD. The total extract of RS (TE) affected 22 of these biomarkers, with the small molecule components of RS (SN) significantly influencing 19 and the large molecule components of RS (PR) impacting 14. Nine small molecule components are likely to dominate the pharmacodynamics of RS. We constructed a target interaction network based on the corresponding bioactivities that revealed relationships amongst 11 key biomarkers, 8 active ingredients and 12 critical targets. This research illustrates the immense potential of spatial metabolomics and network pharmacology in the study of TCM, revealing the targets and mechanisms underlying herbal formulas.

19.
J Hazard Mater ; 476: 135035, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38941838

RESUMO

The hydrogen molecule can effectively regulate plant growth and development, improving plant resistance to abiotic stresses. However, studies regarding the optimal concentration of hydrogen and the associated mechanisms of action in organisms are lacking. This study showed that the maximum germination rate of radish seeds decreased from 90 % to 50 % under the stress of cadmium ions (Cd2+), and hydrogen nanobubble (NB) water significantly alleviated the stress effect of Cd2+ on radish seed germination. A hydrogen concentration of 0.8 ppm had the best effect, reducing Cd2+ accumulation in radish seeds by 63.23 % and increasing the maximum germination rate from 50 % to 65 %. At concentrations exceeding 1.2 ppm, the beneficial effect of hydrogen was weakened or even reversed. Consequently, we integrated the concept of the oxidative window into a REDOX balance model and demonstrated that an appropriate hydrogen concentration can effectively maintain the REDOX state within organisms. Transcriptome sequencing analysis revealed that hydrogen NB water modulated Cd2+ absorption and accumulation in seeds by regulating cell wall components, alleviating oxidative stress through oxidoreductase activity, and enhancing nutrient synthesis and metabolism. This collectively alleviated the inhibitory effect of Cd2+ on seed germination. This study is helpful for further understanding the effect of hydrogen concentration on the REDOX balance of seed germination, providing a theoretical basis for selecting hydrogen concentration to improve its effectiveness in agricultural fields.

20.
Colloids Surf B Biointerfaces ; 241: 114042, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38924850

RESUMO

In the field of orthopedics, surgeons have long been facing the challenge of loosening of external fixation screws due to inherent material characteristics. Despite Polyetheretherketone (PEEK) being employed as an orthopedic implant material for many years, its bio-inert nature often hinders bone healing due to the limited bioactivity, which restricts its clinical applications. Herein, a new type of orthopedic implant (Sr-SPK) was developed by introducing strontium (Sr)-doped mesoporous bioactive glass (Sr-MBG) onto the surface of PEEK implants through a simple and feasible method. In vitro experiments revealed that Sr-SPK effectively promotes osteogenic differentiation while concurrently suppressing the formation of osteoclasts. The same results were validated in vivo with Sr-SPK significantly improving bone integration. Upon investigation, it was found that Sr-SPK promotes adhesion among bone marrow mesenchymal stem cells (BMSCs) thereby promoting osteogenesis by activating the regulation of actin cytoskeletal and focal adhesion pathways, as identified via transcriptome analysis. In essence, these findings suggest that the newly constructed Sr-doped biofunctionalized PEEK implant developed in this research can promote osteoblast differentiation and suppress osteoclast activity by enhancing cell adhesion processes. These results underline the immense potential of such an implant for wide-ranging clinical applications in orthopedics.

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