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1.
Org Lett ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093330

RESUMEN

We developed a protocol for the synthesis of highly functionalized 5,6-dihydro-imidazo[1,2-c][1,2,3]triazole derivatives 4-5 (DHITs) from 1-diazonaphthalen-2(1H)-one derivatives with heterocyclic ketene aminals (HKAs). This strategy involved cycloaddition and skeletal rearrangement entailing the heating of a mixture of substrates 1 with HKAs 2-3 and THF without any catalyst. As a result, a series of DHITs 4-5 were produced by cleaving one bond (1 C═N bond) and forming three bonds (1 N-N and 2 C-N bonds) in a single step. This protocol achieved the dual functionalization of diazo building blocks involving both the aromatic nitrogen alkylation reaction to form an ArC-N bond without any metal catalyst and the intermolecular cycloaddition of the N═N bond. These strategies can be used to synthesize functionalized DHITs for combinatorial and parallel syntheses via one-pot reactions without any catalyst.

2.
BMC Genomics ; 25(1): 783, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138389

RESUMEN

Soybean represents a vital source of premium plant-based proteins for human nutrition. Importantly, the level of water-soluble protein (WSP) is crucial for determining the overall quality and nutritional value of such crops. Enhancing WSP levels in soybean plants is a high-priority goal in crop improvement. This study aimed to elucidate the genetic basis of WSP content in soybean seeds by identifying quantitative trait loci (QTLs) and set the foundation for subsequent gene cloning and functional analysis. Using 180 F10 recombinant inbred lines generated by crossing the high-protein soybean cultivar JiDou 12 with the wild variety Ye 9, our researcher team mapped the QTLs influencing protein levels, integrating Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and gene expression profiling to identify candidate genes. During the 2020 and 2022 growing seasons, a standard bell-shaped distribution of protein content trait data was observed in these soybean lines. Eight QTLs affecting protein content were found across eight chromosomes, with LOD scores ranging from 2.59 to 7.30, explaining 4.15-11.74% of the phenotypic variance. Notably, two QTLs were newly discovered, one with a elite allele at qWSPC-15 from Ye 9. The major QTL, qWSPC-19, on chromosome 19 was stable across conditions and contained genes involved in nitrogen metabolism, amino acid biosynthesis, and signaling. Two genes from this QTL, Glyma.19G185700 and Glyma.19G186000, exhibited distinct expression patterns at maturity, highlighting the influence of these genes on protein content. This research revealed eight QTLs for WSP content in soybean seeds and proposed a gene for the key QTL qWSPC-19, laying groundwork for gene isolation and enhanced soybean breeding through the use of molecular markers. These insights are instrumental for developing protein-rich soybean cultivars.


Asunto(s)
Mapeo Cromosómico , Glycine max , Sitios de Carácter Cuantitativo , Semillas , Glycine max/genética , Glycine max/metabolismo , Semillas/genética , Semillas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Agua/metabolismo , Solubilidad , Fenotipo
3.
Int Ophthalmol ; 44(1): 339, 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39097840

RESUMEN

BACKGROUND: The first line treatment for moderate to severe active thyroid associated ophthalmopathy is glucocorticoid pulse therapy, but for patients with contraindications to hormone therapy or hormone resistance, it is urgent to find a suitable treatment plan. AIMS: To find a reliable alternative to hormone pulse therapy for thyroid associated ophthalmopathy by comparing the efficacy with first-line treatment regimens. METHODS: Search PubMed, Ovid, Web of science, Cochrane library, and Clinical Trials.gov for randomized controlled trials on the treatment of thyroid associated ophthalmopathy published as of July 7, 2024. Quality evaluation and Bayesian network analysis were conducted using RevMan 5.3 software, STATA15.0 software, and ADDIS 1.16.8 software. RESULTS: A total of 666 patients were included in 11 studies and 8 interventions. Network analysis showed that the three interventions of mycophenolate mofetil combined with glucocorticoids, Teprotumumab and 99Tc-MDP were superior to glucocorticoid pulse therapy in improving clinical activity scores and proptosis. The regimen of glucocorticoids combined with statins can improve the quality of life score and diplopia score of patients. Neither methotrexate combined with glucocorticoids nor rituximab alone showed additional advantages when compared with glucocorticoid pulse therapy. CONCLUSION: Mycophenolate mofetil combined with glucocorticoid therapy is very beneficial for moderate to severe active thyroid associated ophthalmopathy. Mycophenolate mofetil may be a good choice when patients have contraindications to hormone use or hormone resistance. Teprotumumab is very promising and may be able to avoid patients undergoing orbital decompression surgery. The durability and safety of its long-term efficacy need to be further observed.


Asunto(s)
Teorema de Bayes , Glucocorticoides , Oftalmopatía de Graves , Humanos , Oftalmopatía de Graves/tratamiento farmacológico , Oftalmopatía de Graves/diagnóstico , Glucocorticoides/uso terapéutico , Glucocorticoides/administración & dosificación , Metaanálisis en Red , Calidad de Vida , Anticuerpos Monoclonales Humanizados
4.
Mil Med Res ; 11(1): 55, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138529

RESUMEN

BACKGROUND: Cervical and breast cancers are among the top 4 leading causes of cancer-related mortality in women. This study aimed to examine age-specific temporal trends in mortality for cervical and breast cancers in urban and rural areas of China from 2009 to 2021. METHODS: Age-specific mortality data for cervical and breast cancers among Chinese women aged 20-84 years were obtained from China's National Disease Surveillance Points system spanning the years 2009 to 2021. Negative binomial regression models were utilized to assess urban-rural differences in mortality rate ratios, while Joinpoint models with estimated average annual percent changes (AAPC) and slopes were employed to compare temporal trends and the acceleration of mortality rates within different age groups. RESULTS: From 2009 to 2021, there was a relative increase in age-specific mortality associated with the two cancers observed in rural areas compared with urban areas. A rising trend in the screening age of 35-64 [AAPC: 4.0%, 95% confidence interval (CI) 0.5-7.6%, P = 0.026] for cervical cancer was noted in rural areas, while a stable trend (AAPC: - 0.7%, 95% CI - 5.8 to 4.6%, P = 0.78) was observed in urban areas. As for breast cancer, a stable trend (AAPC: 0.3%, 95% CI - 0.3 to 0.9%, P = 0.28) was observed in rural areas compared to a decreasing trend (AAPC: - 2.7%, 95% CI - 4.6 to - 0.7%, P = 0.007) in urban areas. Urban-rural differences in mortality rates increased over time for cervical cancer but decreased for breast cancer. Mortality trends for both cervical and breast cancers showed an increase with age across 4 segments, with the most significant surge in mortality observed among the 35-54 age group across urban and rural areas, periods, and regions in China. CONCLUSIONS: Special attention should be given to women aged 35-54 years due to mortality trends and rural-urban disparities. Focusing on vulnerable age groups and addressing rural-urban differences in the delivery of cancer control programs can enhance resource efficiency and promote health equity.


Asunto(s)
Neoplasias de la Mama , Población Rural , Población Urbana , Neoplasias del Cuello Uterino , Humanos , Femenino , Persona de Mediana Edad , Neoplasias de la Mama/mortalidad , Adulto , China/epidemiología , Anciano , Neoplasias del Cuello Uterino/mortalidad , Población Rural/estadística & datos numéricos , Población Rural/tendencias , Población Urbana/estadística & datos numéricos , Población Urbana/tendencias , Anciano de 80 o más Años , Adulto Joven , Mortalidad/tendencias , Factores de Edad
5.
PLoS One ; 19(8): e0301875, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39141645

RESUMEN

BACKGROUND: Ginseng Radix et Rhizoma (GS) is frequently used as an adjuvant therapy for patients with heart failure (HF). Metoprolol is widely used in patients with HF. However, there is no report on the combined effects of GS and metoprolol in patients with HF. OBJECTIVE: This study investigated the combined effects of GS and metoprolol in male C57BL/6J mice with HF and the underlying mechanisms. MATERIALS AND METHODS: We utilized a mouse myocardial HF model to measure the serum levels of creatine kinase (CK) and creatine kinase-MB form (CK-MB) using an automated biochemical analyzer. Lactate dehydrogenase (LDH) and cardiac troponin (cTnT) levels were determined using enzyme-linked immunosorbent assays. Autophagy of myocardial cells was evaluated using transmission electron microscopy, and changes in signal pathway proteins related to autophagy were analyzed by Western blotting. RESULTS: GS combined with metoprolol improved heart function, reduced heart damage, and decreased serum levels of CK, CK-MB, LDH, and cTnT. The combination of GS and metoprolol decreased autophagy in myocardial cells by reducing the levels of autophagy-related proteins (LC3, p62, Beclin1, and Atg5) and increasing the ratios of p-PI3K/PI3K, p-Akt/Akt, and p-mTOR/mTOR. CONCLUSION: GS enhanced the anti-heart failure effect of metoprolol. Its mechanism of action might be related to the inhibition of autophagy mediated by the activation of the PI3K/Akt/mTOR pathway.


Asunto(s)
Autofagia , Insuficiencia Cardíaca , Metoprolol , Ratones Endogámicos C57BL , Panax , Animales , Masculino , Autofagia/efectos de los fármacos , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/metabolismo , Metoprolol/farmacología , Ratones , Panax/química , Transducción de Señal/efectos de los fármacos , Enfermedad Crónica , Rizoma/química , Modelos Animales de Enfermedad , L-Lactato Deshidrogenasa/sangre , L-Lactato Deshidrogenasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Extractos Vegetales/farmacología , Creatina Quinasa/sangre , Sinergismo Farmacológico , Forma MB de la Creatina-Quinasa/sangre
6.
Water Res ; 263: 122160, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39096816

RESUMEN

The accurate prediction of chlorophyll-a (chl-a) concentration in coastal waters is essential to coastal economies and ecosystems as it serves as the key indicator of harmful algal blooms. Although powerful machine learning methods have made strides in forecasting chl-a concentrations, there remains a gap in effectively modeling the dynamic temporal patterns and dealing with data noise and unreliability. To wiggle out of quagmires, we introduce an innovative deep learning prediction model (termed ChloroFormer) by integrating Transformer networks with Fourier analysis within a decomposition architecture, utilizing coastal in-situ data from two distinct study areas. Our proposed model exhibits superior capabilities in capturing both short-term and middle-term dependency patterns in chl-a concentrations, surpassing the performance of six other deep learning models in multistep-ahead predictive accuracy. Particularly in scenarios involving extreme and frequent blooms, our proposed model shows exceptional predictive performance, especially in accurately forecasting peak chl-a concentrations. Further validation through Kolmogorov-Smirnov tests attests that our model not only replicates the actual dynamics of chl-a concentrations but also preserves the distribution of observation data, showcasing its robustness and reliability. The presented deep learning model addresses the critical need for accurate prediction on chl-a concentrations, facilitating the exploration of marine observations with complex dynamic temporal patterns, thereby supporting marine conservation and policy-making in coastal areas.

7.
Physiol Plant ; 176(4): e14419, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38973451

RESUMEN

Abiotic stress impairs plant growth and development, thereby causing low yield and inferior quality of crops. Increasing studies reported that strigolactones (SL) are plant hormones that enhance plant stress resistance by regulating plant physiological processes and gene expressions. In this review, we introduce the response and regulatory role of SL in salt, drought, light, heat, cold and cadmium stresses in plants. This review also discusses how SL alleviate the damage of abiotic stress in plants, furthermore, introducing the mechanisms of SL enhancing plant stress resistance at the genetic level. Under abiotic stress, the exogenous SL analog GR24 can induce the biosynthesis of SL in plants, and endogenous SL can alleviate the damage caused by abiotic stress. SL enhanced the stress resistance of plants by protecting photosynthesis, enhancing the antioxidant capacity of plants and promoting the symbiosis between plants and arbuscular mycorrhiza (AM). SL interact with abscisic acid (ABA), salicylic acid (SA), auxin, cytokinin (CK), jasmonic acid (JA), hydrogen peroxide (H2O2) and other signal molecules to jointly regulate plant stress resistance. Lastly, both the importance of SL and their challenges for future work are outlined in order to further elucidate the specific mechanisms underlying the roles of SL in plant responses to abiotic stress.


Asunto(s)
Lactonas , Reguladores del Crecimiento de las Plantas , Estrés Fisiológico , Lactonas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Plantas/metabolismo , Plantas/efectos de los fármacos , Plantas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos
8.
Magn Reson Imaging ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39033886

RESUMEN

OBJECTIVES: This study aims to generate post-contrast MR images reducing the exposure of gadolinium-based contrast agents (GBCAs) for brainstem glioma (BSG) detection, simultaneously delineating the BSG lesion, and providing high-resolution contrast information. METHODS: A retrospective cohort of 30 patients diagnosed with brainstem glioma was included. Multi-contrast images, including pre-contrast T1 weighted (pre-T1w), T2 weighted (T2w), arterial spin labeling (ASL) and post-contrast T1w images, were collected. A multi-task generative model was developed to synthesize post-contrast T1w images and simultaneously segment BSG masks from the multi-contrast inputs. Performance evaluation was conducted using peak signal-to-noise ratio (PSNR), structural similarity index (SSIM), and mean absolute error (MAE) metrics. A perceptual study was also undertaken to assess diagnostic quality. RESULTS: The proposed model achieved SSIM of 0.86 ±â€¯0.04, PSNR of 26.33 ±â€¯0.05 and MAE of 57.20 ±â€¯20.50 for post-contrast T1w image synthesis. Automated delineation of the BSG lesions achieved Dice similarity coefficient (DSC) score of 0.88 ±â€¯0.27. CONCLUSIONS: The proposed model can synthesize high-quality post-contrast T1w images and accurately segment the BSG region, yielding satisfactory DSC scores. CLINICAL RELEVANCE STATEMENT: The synthesized post-contrast MR image presented in this study has the potential to reduce the usage of gadolinium-based contrast agents, which may pose risks to patients. Moreover, the automated segmentation method proposed in this paper aids radiologists in accurately identifying the brainstem glioma lesion, facilitating the diagnostic process.

9.
Plant Cell Rep ; 43(7): 180, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914787

RESUMEN

KEY MESSAGE: Hydrogen sulfide improved cold resistance of tomato fruits by regulating energy metabolism and delaying cell wall degradation, thereby alleviating the damage of cold storage on fruits. Postharvest cold storage in tomato fruits extended shelf life but caused the appearance of chilling injury (CI), appeared by softness and spots on the surface of the fruits. These changes were linked closely with energy and cell wall metabolisms. Hydrogen sulfide (H2S), as the gaseous fresh-keeping regulator, was used in the present study to investigate the effects of H2S on energy and cell wall metabolisms in tomato fruits during cold storage. Fruits after harvest were fumigated with different concentrations (0, 0.5, 1, 1.5 mM) of sodium hydrosulfide (NaHS) solution as H2S honor for 24 h and stored at 4 °C for 25 days. The results showed that 1 and 1.5 mM NaHS solution fumigation promoted the accumulation of endogenous H2S, followed by the increase in L-cysteine desulfurase (LCD) and D-cysteine desulfurase (DCD) activities in fruits during cold storage. It was also found that 1 and 1.5 mM NaHS treatments improved H+-ATPase, Ca2+-ATPase, cytochrome C oxidase (CCO), and succinic dehydrogenase (SDH) activities. Moreover, the contents of cellulose and hemicellulose were increased by 1 and 1.5 mM NaHS, following down-regulated activities of cellulase (CL), pectin lyase (PL), α-mannosidase (α-man) and ß-Galactosidase (ß-Gal) and down-regulated expression of PL1, PL8, MAN4 and MAN7 genes. Thus, H2S alleviates CI led by cold storage in tomato fruits via regulating energy and cell wall metabolisms.


Asunto(s)
Pared Celular , Frío , Metabolismo Energético , Frutas , Sulfuro de Hidrógeno , Solanum lycopersicum , Pared Celular/metabolismo , Sulfuro de Hidrógeno/farmacología , Sulfuro de Hidrógeno/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiología , Frutas/metabolismo , Frutas/genética , Frutas/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Almacenamiento de Alimentos/métodos , Sulfuros/farmacología , Sulfuros/metabolismo
10.
Heliyon ; 10(11): e32133, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38868052

RESUMEN

Carbon dots (CDs), as a new kind of fluorescent nanomaterials, show great potential for application in several fields due to their unique nano-size effect, easy surface functionalization, controllable photoluminescence, and excellent biocompatibility. Conventional preparation methods for CDs typically involve top-down and bottom-up approaches. Doping is a major step forward in CDs design methodology. Chemical doping includes both non-metal and metal doping, in which non-metal doping is an effective strategy for modulating the fluorescence properties of CDs and improving photocatalytic performance in several areas. In recent years, Metal-doped CDs have aroused the interest of academics as a promising nano-doping technique. This approach has led to improvements in the physicochemical and optical properties of CDs by altering their electron density distribution and bandgap capacity. Additionally, the issues of metal toxicity and utilization have been addressed to a large extent. In this review, we categorize metals into two major groups: transition group metals and rare-earth group metals, and an overview of recent advances in biomedical applications of these two categories, respectively. Meanwhile, the prospects and the challenges of metal-doped CDs for biomedical applications are reviewed and concluded. The aim of this paper is to break through the existing deficiencies of metal-doped CDs and fully exploit their potential. I believe that this review will broaden the insight into the synthesis and biomedical applications of metal-doped CDs.

11.
Exp Mol Med ; 56(7): 1574-1590, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38945950

RESUMEN

The hypoxia-inducible factor-1α (HIF-1α) pathway coordinates skeletal bone homeostasis and endocrine functions. Activation of the HIF-1α pathway increases glucose uptake by osteoblasts, which reduces blood glucose levels. However, it is unclear whether activating the HIF-1α pathway in osteoblasts can help normalize glucose metabolism under diabetic conditions through its endocrine function. In addition to increasing bone mass and reducing blood glucose levels, activating the HIF-1α pathway by specifically knocking out Von Hippel‒Lindau (Vhl) in osteoblasts partially alleviated the symptoms of streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM), including increased glucose clearance in the diabetic state, protection of pancreatic ß cell from STZ-induced apoptosis, promotion of pancreatic ß cell proliferation, and stimulation of insulin secretion. Further screening of bone-derived factors revealed that islet regeneration-derived protein III gamma (RegIIIγ) is an osteoblast-derived hypoxia-sensing factor critical for protection against STZ-induced T1DM. In addition, we found that iminodiacetic acid deferoxamine (SF-DFO), a compound that mimics hypoxia and targets bone tissue, can alleviate symptoms of STZ-induced T1DM by activating the HIF-1α-RegIIIγ pathway in the skeleton. These data suggest that the osteoblastic HIF-1α-RegIIIγ pathway is a potential target for treating T1DM.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Subunidad alfa del Factor 1 Inducible por Hipoxia , Osteoblastos , Animales , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/etiología , Osteoblastos/metabolismo , Osteoblastos/efectos de los fármacos , Ratones , Transducción de Señal/efectos de los fármacos , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética , Masculino , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Estreptozocina , Apoptosis/efectos de los fármacos , Glucemia/metabolismo
12.
Molecules ; 29(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38731522

RESUMEN

Cardiovascular disease has become a common ailment that endangers human health, having garnered widespread attention due to its high prevalence, recurrence rate, and sudden death risk. Ginseng possesses functions such as invigorating vital energy, enhancing vein recovery, promoting body fluid and blood nourishment, calming the nerves, and improving cognitive function. It is widely utilized in the treatment of various heart conditions, including palpitations, chest pain, heart failure, and other ailments. Although numerous research reports have investigated the cardiovascular activity of single ginsenoside, there remains a lack of systematic research on the specific components group that predominantly contribute to cardiovascular efficacy in ginseng medicinal materials. In this research, the spectrum-effect relationship, target cell extraction, and BP neural network classification were used to establish a rapid screening system for potential active substances. The results show that red ginseng extract (RGE) can improve the decrease in cell viability and ATP content and inhibit the increase in ROS production and LDH release in OGD-induced H9c2 cells. A total of 70 ginsenosides were identified in RGE using HPLC-Q-TOF-MS/MS analysis. Chromatographic fingerprints were established for 12 batches of RGE by high-performance liquid chromatography (HPLC). A total of 36 common ingredients were found in 12 batches of RGE. The cell viability, ATP, ROS, and LDH of 12 batches RGE were tested to establish gray relationship analysis (GRA) and partial least squares discrimination analysis (PLS-DA). BP neural network classification and target cell extraction were used to narrow down the scope of Spectral efficiency analysis and screen the potential active components. According to the cell experiments, RGE can improve the cell viability and ATP content and reduce the oxidative damage. Then, seven active ingredients, namely, Ginsenoside Rg1, Rg2, Rg3, Rb1, Rd, Re, and Ro, were screened out, and their cardiovascular activity was confirmed in the OGD model. The seven ginsenosides were the main active substances of red ginseng in treating myocardial injury. This study offers a reference for quality control in red ginseng and preparations containing red ginseng for the management of cardiovascular diseases. It also provides ideas for screening active ingredients of the same type of multi-pharmacologically active traditional Chinese medicines.


Asunto(s)
Supervivencia Celular , Ginsenósidos , Redes Neurales de la Computación , Panax , Extractos Vegetales , Panax/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Ginsenósidos/farmacología , Ginsenósidos/química , Ginsenósidos/aislamiento & purificación , Supervivencia Celular/efectos de los fármacos , Ratas , Animales , Línea Celular , Especies Reactivas de Oxígeno/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Cromatografía Líquida de Alta Presión , Humanos , Espectrometría de Masas en Tándem
13.
Ying Yong Sheng Tai Xue Bao ; 35(3): 659-668, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38646753

RESUMEN

To accurately monitor the phenology of net ecosystem carbon exchange (NEE) in grasslands with remote sensing, we analyzed the variations in NEE and its phenology in the Stipa krylovii steppe and discussed the remote sensing vegetation index thresholds for NEE phenology, with the observational data from the Inner Mongolia Xilinhot National Climate Observatory's eddy covariance system and meteorological gradient observation system during 2018-2021, as well as Sentinel-2 satellite data from January 1, 2018 to December 31, 2021. Results showed that, from 2018 to 2021, NEE exhibited seasonal variations, with carbon sequestration occurring from April to October and carbon emission in other months, resulting in an overall carbon sink. The average Julian days for the start date (SCUP) and the end date (ECUP) of carbon uptake period were the 95th and 259th days, respectively, with an average carbon uptake period lasting 165 days. Photosynthetically active radiation showed a negative correlation with daily NEE, contributing to carbon absorption of grasslands. The optimal threshold for capturing SCUP was a 10% threshold of the red-edge chlorophyll index, while the normalized difference vegetation index effectively reflected ECUP with a threshold of 75%. These findings would provide a basis for remote sensing monitoring of grassland carbon source-sink dynamics.


Asunto(s)
Carbono , Ecosistema , Monitoreo del Ambiente , Pradera , Poaceae , Tecnología de Sensores Remotos , China , Carbono/metabolismo , Poaceae/metabolismo , Poaceae/crecimiento & desarrollo , Monitoreo del Ambiente/métodos , Secuestro de Carbono , Estaciones del Año , Ciclo del Carbono
14.
J Biomed Mater Res B Appl Biomater ; 112(3): e35400, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38456343

RESUMEN

Lithium disilicate (Li2 Si2 O5 ) glass-ceramics are currently a more widely used all-ceramic restorative material due to their good mechanical properties and excellent aesthetic properties. However, they have a series of problems such as high brittleness and low fracture toughness, which has become the main bottleneck restricting its development. Therefore, in order to compensate for these shortcomings, we propose to prepare a reinforced glass-ceramics with better mechanical properties and to test the biosafety and chemical solubility of the material. Li2 Si2 O5 whiskers were synthesized by a one-step hydrothermal method, and multi-scale crystal-enhanced Li2 Si2 O5 glass-ceramics were prepared by reaction sintering. The biosafety of multi-scale crystal-reinforced Li2 Si2 O5 glass-ceramics was investigated by in vitro cytotoxicity test, rabbit pyrogen test, mice bone marrow micronucleus test, skin sensitization test, sub-chronic systemic toxicity test, and chronic systemic toxicity test. Additionally, the chemical solubility of multi-scale crystal-reinforced Li2 Si2 O5 glass-ceramics was investigated. The test results showed that the material was non-cytotoxic, non-thermogenic, non-mutagenic, non-sensitizing, and non-systemic. The chemical solubility, determined to be 377 ± 245 µg/cm2 , complied with the ISO 6872 standard for the maximum solubility of ceramic materials. Multi-scale crystal-reinforced Li2 Si2 O5 glass-ceramics' biosafety and chemical solubility met current normative criteria, and they can move on to mechanical property measurements (such as flexural strength test, fatigue life test, friction and wear property study, etc.) and bonding property optimization, which shows promise for future clinical applications.


Asunto(s)
Cerámica , Contención de Riesgos Biológicos , Animales , Ratones , Conejos , Ensayo de Materiales , Solubilidad , Propiedades de Superficie , Cerámica/química , Porcelana Dental , Litio
15.
Chemistry ; 30(30): e202400946, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38516955

RESUMEN

Starfish provide important saponins with diverse bioactivities as the secondary metabolites, among which 2-O-glycosylated glycosides are commonly found. Preparation of those 1,2-trans 2-O-glycosylated glycosides usually relies on 2-O-acyl participation requiring the selective installation and cleavage of 2-O-acyl groups. A convergent synthesis using 2-O-glycosylated oligosaccharide donors would be more straightforward but also pose greater challenges. Herein, we report a convergent synthesis of a distinctive tetrasaccharide isolated from starfish Asterias rollestoni Bell. Dual 2-(diphenylphosphinoyl)acetyl (DPPA) groups at O3 and O4 on galactose moiety led to high ß-selectivities (ß/α=12/1 or ß only) in the challenging [2+2] glycosylation, giving the desired tetrasaccharides in >90 % yields from the 2-O-glycosylated disaccharide donors. These synthetic studies have also unambiguously revised the structure of these natural tetrasaccharides. This work would facilitate further studies on new inhibitors of α-glucosidase as hypoglycemic drugs.


Asunto(s)
Oligosacáridos , Animales , Glicosilación , Oligosacáridos/química , Oligosacáridos/síntesis química , Asterias/química , Glicósidos/química , Saponinas/química , Saponinas/síntesis química , alfa-Glucosidasas/metabolismo , alfa-Glucosidasas/química
16.
J Hazard Mater ; 468: 133785, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38367441

RESUMEN

BACKGROUND: Although growing evidence has shown independent links of long-term exposure to fine particulate matter (PM2.5) with cognitive impairment, the effects of its constituents remain unclear. This study aims to explore the associations of long-term exposure to ambient PM2.5 constituents' mixture with cognitive impairment in Chinese older adults, and to further identify the main contributor. METHODS: 15,274 adults ≥ 65 years old were recruited by the Chinese Longitudinal Healthy Longevity Study (CLHLS) and followed up through 7 waves during 2000-2018. Concentrations of ambient PM2.5 and its constituents (i.e., black carbon [BC], organic matter [OM], ammonium [NH4+], sulfate [SO42-], and nitrate [NO3-]) were estimated by satellite retrievals and machine learning models. Quantile-based g-computation model was employed to assess the joint effects of a mixture of 5 PM2.5 constituents and their relative contributions to cognitive impairment. Analyses stratified by age group, sex, residence (urban vs. rural), and region (north vs. south) were performed to identify vulnerable populations. RESULTS: During the average 3.03 follow-up visits (89,296.9 person-years), 4294 (28.1%) participants had developed cognitive impairment. The adjusted hazard ratio [HR] (95% confidence interval [CI]) for cognitive impairment for every quartile increase in mixture exposure to 5 PM2.5 constituents was 1.08 (1.05-1.11). BC held the largest index weight (0.69) in the positive direction in the qg-computation model, followed by OM (0.31). Subgroup analyses suggested stronger associations in younger old adults and rural residents. CONCLUSION: Long-term exposure to ambient PM2.5, particularly its constituents BC and OM, is associated with an elevated risk of cognitive impairment onset among Chinese older adults.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Disfunción Cognitiva , Humanos , Anciano , Material Particulado/toxicidad , Estudios de Cohortes , Contaminantes Atmosféricos/toxicidad , Exposición a Riesgos Ambientales , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/epidemiología , China/epidemiología , Contaminación del Aire/efectos adversos
17.
J Sep Sci ; 47(1): e2300545, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38234026

RESUMEN

Pseudoallergy is a typical and common adverse drug reaction to injections, especially in traditional Chinese medicine injections (TCMIs). At present, the evaluation methods for pseudoallergy include cell methods in vitro and animal methods in vivo. The mast cell evaluation method based on the ß-hexosaminidase (ß-Hex)-catalyzed substrate, 4-nitrophenyl-ß-N-acetyl-D-glucosaminide (4-NPG), is an important method for the evaluation of drug-induced pseudoallergy, but it is prone to false positive results and has insufficient sensitivity. In this study, a novel ß-Hex evaluation system with rat basophilic leukemia-2H3 cells based on high-performance liquid chromatography-fluorescence detection (HPLC-FLD) was established, which effectively increased the sensitivity and avoided false positive results. Cell viabilities were measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide assay. In addition, a method for the determination of histamine, which is another indicator in the development of pseudoallergy, was established to validate the above method. The results of this novel method indicated that two TCMIs (Shuxuening injection and Shenqi Fuzheng injection), which were considered to be pseudoallergenic using 4-NPG, were not pseudoallergenic. Overall, the novel ß-Hex/HPLC-FLD evaluation system using Rat basophilic leukemia-2H3 cells established was effective and precise. It could be used for the evaluation of pseudoallergic reactions caused by TCMIs and other injections.


Asunto(s)
Medicamentos Herbarios Chinos , Leucemia , Ratas , Animales , Medicina Tradicional China , beta-N-Acetilhexosaminidasas , Inyecciones , Histamina
18.
Cancer Cell Int ; 24(1): 31, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38218960

RESUMEN

BACKGROUND: GPR65 is a pH-sensing G-protein-coupled receptor that acts as a key innate immune checkpoint in the human tumor microenvironment, inhibiting the release of inflammatory factors and inducing significant upregulation of tissue repair genes. However, the expression pattern and function of GPR65 in osteosarcoma (OS) remain unclear. The purpose of this study was to investigate and elucidate the role of GPR65 in the microenvironment, proliferation and migration of OS. METHODS: Retrospective RNA-seq data analysis was conducted in a cohort of 97 patients with OS data in the TAEGET database. In addition, single-cell sequencing data from six surgical specimens of human OS patients was used to analyze the molecular evolution process during OS genesis. Tissues chips and bioinformatics results were used to verify GPR65 expression level in OS. MTT, colony formation, EdU assay, wound healing, transwell assay and F-actin assay were utilized to analyze cell proliferation and invasion of OS cancer cells. RNA-seq was used to explore the potential mechanism of GPR65's role in OS. RESULTS: GPR65 expression was significantly low in OS, and subgroup analysis found that younger OS patients, OS patients in metastatic status, and overall survival and progression free survival OS patients had lower GPR65 expression. From ScRNA-seq data of GSE162454, we found the expression of GPR65 is significantly positively correlated with CD4 + T cells CD8 + T cells and OS related macrophage infiltration. Verification experiment found that silencing the expression of GPR65 in osteosarcoma cells U2OS and HOS could promote the proliferation and invasion process, RNA-seq results showed that the role of GPR65 in OS cells was related to immune system, metabolism and signal transduction. CONCLUSION: The low expression of GPR65 in OS leads to high metastasis rate and poor prognosis in OS patients. The suppression of immune escape and inhibition of proliferation may be a key pathway for GPR65 to participate in the progression of OS. The current study strengthens the role of GPR65 in OS development and provides a potential biomarker for the prognosis of OS patients.

19.
Integr Cancer Ther ; 23: 15347354231226108, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38240227

RESUMEN

OBJECTIVE: In China, grade 2 to 3 immune-related rash will probably lead to the interruption of immunotherapy. Corticosteroid (CS) is the main treatment, but not always effective. The external application of clearing heat and removing dampness, which is represented by Qing-Re-Li-Shi Formula (QRLSF), has been used in our hospital to treat immune-related cutaneous adverse events (ircAEs) for the last 5 years. The purpose of this study was to discuss its efficacy and safety in the treatment of grade 2 to 3 rash. METHODS: A retrospective study of patients with grade 2 to 3 immune-related rash in our hospital from December 2019 to December 2022 was conducted. These patients received QRLSF treatment. Clinical characteristics, treatment outcome, and health-related quality of life (HrQoL) were analyzed. RESULTS: Thirty patients with grade 2 to 3 rash (median onset time: 64.5 days) were included. The skin lesions of 24 cases (80%) returned to grade 1 with a median time of 8 days. The accompanying symptoms were also improved with median time of 3 to 4 days. The addition of antihistamine (AH) drug didn't increase the efficacy of QRLSF (AH + QRLSF: 75.00% vs QRLSF: 83.33%, P = .66). No significant difference was observed in the efficacy of QRLSF treatment regardless of whether patients had previously received CS therapy (untreated population: 88.24% vs treated population: 69.23%, P = .36). During 1-month follow-up, 2 cases (8.33%) underwent relapses. In terms of HrQoL, QRLSF treatment could significantly reduce the median scores of all domains of Skindex-16, including symptoms (39.58 vs 8.33, P < .0001), emotions (58.33 vs 15.48, P < .0001), functioning (46.67 vs 13.33, P < .0001) and composite (52.60 vs 14.06, P < .0001). CONCLUSION: External application of clearing heat and removing dampness was proven to be an effective and safe treatment for such patients. In the future, high-quality trials are required to determine its clinical application in the field of ircAEs.


Asunto(s)
Antígeno B7-H1 , Exantema , Receptor de Muerte Celular Programada 1 , Humanos , Antígeno B7-H1/antagonistas & inhibidores , Exantema/inducido químicamente , Exantema/tratamiento farmacológico , Calor , Ligandos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Calidad de Vida , Estudios Retrospectivos
20.
Adv Sci (Weinh) ; 11(1): e2304824, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37953457

RESUMEN

A fundamental understanding of inflammation and tissue healing suggests that the precise regulation of the inflammatory phase, both in terms of location and timing, is crucial for bone regeneration. However, achieving the activation of early inflammation without causing chronic inflammation while facilitating quick inflammation regression to promote bone regeneration continues to pose challenges. This study reveals that black phosphorus (BP) accelerates bone regeneration by building an osteogenic immunological microenvironment. BP amplifies the acute pro-inflammatory response and promotes the secretion of anti-inflammatory factors to accelerate inflammation regression and tissue regeneration. Mechanistically, BP creates an osteoimmune-friendly microenvironment by stimulating macrophages to express interleukin 33 (IL-33), amplifying the inflammatory response at an early stage, and promoting the regression of inflammation. In addition, BP-mediated IL-33 expression directly promotes osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), which further facilitates bone repair. To the knowledge, this is the first study to reveal the immunomodulatory potential of BP in bone regeneration through the regulation of both early-stage inflammatory responses and later-stage inflammation resolution, along with the associated molecular mechanisms. This discovery serves as a foundation for the clinical use of BP and is an efficient approach for managing the immune microenvironment during bone regeneration.


Asunto(s)
Interleucina-33 , Osteogénesis , Humanos , Fósforo , Regeneración Ósea , Inflamación/metabolismo
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