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1.
Proc Natl Acad Sci U S A ; 121(14): e2302967120, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38547063

RESUMEN

It is well-known that highly reactive hydroxyl radicals (HO•) can be produced by the classic Fenton system and our recently discovered haloquinone/H2O2 system, but rarely from thiol-derivatives. Here, we found, unexpectedly, that HO• can be generated from H2O2 and thiourea dioxide (TUO2), a widely used and environmentally friendly bleaching agent. A carbon-centered radical and sulfite were detected and identified as the transient intermediates, and urea and sulfate as the final products, with the complementary application of electron spin-trapping, oxygen-18 isotope labeling coupled with HPLC/MS analysis. Density functional theory calculations were conducted to further elucidate the detailed pathways for HO• production. Taken together, we proposed that the molecular mechanism for HO• generation by TUO2/H2O2: TUO2 tautomerizes from sulfinic acid into ketone isomer (TUO2-K) through proton transfer, then a nucleophilic addition of H2O2 on the S atom of TUO2-K, forming a S-hydroperoxide intermediate TUO2-OOH, which dissociates homolytically to produce HO•. Our findings represent the first experimental and computational study on an unprecedented new molecular mechanism of HO• production from simple thiol-derived sulfinic acids, which may have broad chemical, environmental, and biomedical significance for future research on the application of the well-known bleaching agent and its analogs.

2.
J Biol Chem ; 300(7): 107413, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38810698

RESUMEN

Ataxin-2 (Atx2) is a polyglutamine (polyQ) tract-containing RNA-binding protein, while its polyQ expansion may cause protein aggregation that is implicated in the pathogenesis of neurodegenerative diseases such as spinocerebellar ataxia type 2 (SCA2). However, the molecular mechanism underlying how Atx2 aggregation contributes to the proteinopathies remains elusive. Here, we investigated the influence of Atx2 aggregation on the assembly and functionality of cellular processing bodies (P-bodies) by using biochemical and fluorescence imaging approaches. We have revealed that polyQ-expanded (PQE) Atx2 sequesters the DEAD-box RNA helicase (DDX6), an essential component of P-bodies, into aggregates or puncta via some RNA sequences. The N-terminal like-Sm (LSm) domain of Atx2 (residues 82-184) and the C-terminal helicase domain of DDX6 are responsible for the interaction and specific sequestration. Moreover, sequestration of DDX6 may aggravate pre-mRNA mis-splicing, and interfere with the assembly of cellular P-bodies, releasing the endoribonuclease MARF1 that promotes mRNA decay and translational repression. Rescuing the DDX6 protein level can recover the assembly and functionality of P-bodies, preventing targeted mRNA from degradation. This study provides a line of evidence for sequestration of the P-body components and impairment of the P-body homeostasis in dysregulating RNA metabolism, which is implicated in the disease pathologies and a potential therapeutic target.


Asunto(s)
Ataxina-2 , ARN Helicasas DEAD-box , Homeostasis , Péptidos , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/genética , Humanos , Ataxina-2/metabolismo , Ataxina-2/genética , Péptidos/metabolismo , Péptidos/química , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Células HEK293 , Ataxias Espinocerebelosas/metabolismo , Ataxias Espinocerebelosas/genética , Agregado de Proteínas , Empalme del ARN , Dominios Proteicos , Precursores del ARN/metabolismo , Precursores del ARN/genética
3.
Plant J ; 118(6): 2055-2067, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38507513

RESUMEN

Culm development in grasses can be controlled by both miR156 and cytokinin. However, the crosstalk between the miR156-SPL module and the cytokinin metabolic pathway remains largely unknown. Here, we found CYTOKININ OXIDASE/DEHYDROGENASE4 (PvCKX4) plays a negative regulatory role in culm development of the bioenergy grass Panicum virgatum (switchgrass). Overexpression of PvCKX4 in switchgrass reduced the internode diameter and length without affecting tiller number. Interestingly, we also found that PvCKX4 was always upregulated in miR156 overexpressing (miR156OE) transgenic switchgrass lines. Additionally, upregulation of either miR156 or PvCKX4 in switchgrass reduced the content of isopentenyl adenine (iP) without affecting trans-zeatin (tZ) accumulation. It is consistent with the evidence that the recombinant PvCKX4 protein exhibited much higher catalytic activity against iP than tZ in vitro. Furthermore, our results showed that miR156-targeted SPL2 bound directly to the promoter of PvCKX4 to repress its expression. Thus, alleviating the SPL2-mediated transcriptional repression of PvCKX4 through miR156 overexpression resulted in a significant increase in cytokinin degradation and impaired culm development in switchgrass. On the contrary, suppressing PvCKX4 in miR156OE transgenic plants restored iP content, internode diameter, and length to wild-type levels. Most strikingly, the double transgenic lines retained the same increased tiller numbers as the miR156OE transgenic line, which yielded more biomass than the wild type. These findings indicate that the miR156-SPL module can control culm development through transcriptional repression of PvCKX4 in switchgrass, which provides a promising target for precise design of shoot architecture to yield more biomass from grasses.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , MicroARNs , Oxidorreductasas , Panicum , Proteínas de Plantas , Citocininas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Panicum/genética , Panicum/crecimiento & desarrollo , Panicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente
4.
Plant J ; 119(3): 1299-1312, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38838090

RESUMEN

Hydrolyzable tannins (HTs), a class of polyphenolic compounds found in dicotyledonous plants, are widely used in food and pharmaceutical industries because of their beneficial effects on human health. Although the biosynthesis of simple HTs has been verified at the enzymatic level, relevant genes have not yet been identified. Here, based on the parent ion-fragment ion pairs in the feature fragment data obtained using UPLC-Q-TOF-/MS/MS, galloyl phenolic compounds in the leaves of Camellia sinensis and C. oleifera were analyzed qualitatively and quantitatively. Correlation analysis between the transcript abundance of serine carboxypeptidase-like acyltransferases (SCPL-ATs) and the peak area of galloyl products in Camellia species showed that SCPL3 expression was highly correlated with HT biosynthesis. Enzymatic verification of the recombinant protein showed that CoSCPL3 from C. oleifera catalyzed the four consecutive steps involved in the conversion of digalloylglucose to pentagalloylglucose. We also identified the residues affecting the enzymatic activity of CoSCPL3 and determined that SCPL-AT catalyzes the synthesis of galloyl glycosides. The findings of this study provide a target gene for germplasm innovation of important cash crops that are rich in HTs, such as C. oleifera, strawberry, and walnut.


Asunto(s)
Aciltransferasas , Camellia , Carboxipeptidasas , Taninos Hidrolizables , Proteínas de Plantas , Camellia/genética , Camellia/enzimología , Camellia/metabolismo , Carboxipeptidasas/metabolismo , Carboxipeptidasas/genética , Aciltransferasas/genética , Aciltransferasas/metabolismo , Taninos Hidrolizables/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/enzimología , Espectrometría de Masas en Tándem
5.
BMC Genomics ; 25(1): 756, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39095710

RESUMEN

BACKGROUND: Long non-coding RNAs (lncRNAs) are RNA transcripts of more than 200 nucleotides that do not encode canonical proteins. Their biological structure is similar to messenger RNAs (mRNAs). To distinguish between lncRNA and mRNA transcripts quickly and accurately, we upgraded the PLEK alignment-free tool to its next version, PLEKv2, and constructed models tailored for both animals and plants. RESULTS: PLEKv2 can achieve 98.7% prediction accuracy for human datasets. Compared with classical tools and deep learning-based models, this is 8.1%, 3.7%, 16.6%, 1.4%, 4.9%, and 48.9% higher than CPC2, CNCI, Wen et al.'s CNN, LncADeep, PLEK, and NcResNet, respectively. The accuracy of PLEKv2 was > 90% for cross-species prediction. PLEKv2 is more effective and robust than CPC2, CNCI, LncADeep, PLEK, and NcResNet for primate datasets (including chimpanzees, macaques, and gorillas). Moreover, PLEKv2 is not only suitable for non-human primates that are closely related to humans, but can also predict the coding ability of RNA sequences in plants such as Arabidopsis. CONCLUSIONS: The experimental results illustrate that the model constructed by PLEKv2 can distinguish lncRNAs and mRNAs better than PLEK. The PLEKv2 software is freely available at https://sourceforge.net/projects/plek2/ .


Asunto(s)
ARN Largo no Codificante , ARN Mensajero , ARN Largo no Codificante/genética , ARN Mensajero/genética , Humanos , Animales , Programas Informáticos , Biología Computacional/métodos
6.
J Transl Med ; 22(1): 545, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849871

RESUMEN

Recently, research on the human microbiome, especially concerning the bacteria within the digestive system, has substantially advanced. This exploration has unveiled a complex interplay between microbiota and health, particularly in the context of disease. Evidence suggests that the gut microbiome plays vital roles in digestion, immunity and the synthesis of vitamins and neurotransmitters, highlighting its significance in maintaining overall health. Conversely, disruptions in these microbial communities, termed dysbiosis, have been linked to the pathogenesis of various diseases, including digestive system cancers. These bacteria can influence cancer progression through mechanisms such as DNA damage, modulation of the tumour microenvironment, and effects on the host's immune response. Changes in the composition and function within the tumours can also impact inflammation, immune response and cancer therapy effectiveness. These findings offer promising avenues for the clinical application of intratumoral bacteria for digestive system cancer treatment, including the potential use of microbial markers for early cancer detection, prognostication and the development of microbiome-targeted therapies to enhance treatment outcomes. This review aims to provide a comprehensive overview of the pivotal roles played by gut microbiome bacteria in the development of digestive system cancers. Additionally, we delve into the specific contributions of intratumoral bacteria to digestive system cancer development, elucidating potential mechanisms and clinical implications. Ultimately, this review underscores the intricate interplay between intratumoral bacteria and digestive system cancers, underscoring the pivotal role of microbiome research in transforming diagnostic, prognostic and therapeutic paradigms for digestive system cancers.


Asunto(s)
Bacterias , Neoplasias del Sistema Digestivo , Humanos , Neoplasias del Sistema Digestivo/microbiología , Neoplasias del Sistema Digestivo/terapia , Bacterias/metabolismo , Microbioma Gastrointestinal , Animales
7.
Appl Environ Microbiol ; 90(7): e0025524, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38874338

RESUMEN

Marine bacteria contribute substantially to cycle macroalgae polysaccharides in marine environments. Carrageenans are the primary cell wall polysaccharides of red macroalgae. The carrageenan catabolism mechanism and pathways are still largely unclear. Pseudoalteromonas is a representative bacterial genus that can utilize carrageenan. We previously isolated the strain Pseudoalteromonas haloplanktis LL1 that could grow on ι-carrageenan but produce no ι-carrageenase. Here, through a combination of bioinformatic, biochemical, and genetic analyses, we determined that P. haloplanktis LL1 processed a desulfurization-depolymerization sequential pathway for ι-carrageenan utilization, which was initiated by key sulfatases PhSulf1 and PhSulf2. PhSulf2 acted as an endo/exo-G4S (4-O-sulfation-ß-D-galactopyranose) sulfatase, while PhSulf1 was identified as a novel endo-DA2S sulfatase that could function extracellularly. Because of the unique activity of PhSulf1 toward ι-carrageenan rather than oligosaccharides, P. haloplanktis LL1 was considered to have a distinct ι-carrageenan catabolic pathway compared to other known ι-carrageenan-degrading bacteria, which mainly employ multifunctional G4S sulfatases and exo-DA2S (2-O-sulfation-3,6-anhydro-α-D-galactopyranose) sulfatase for sulfate removal. Furthermore, we detected widespread occurrence of PhSulf1-encoding gene homologs in the global ocean, indicating the prevalence of such endo-acting DA2S sulfatases as well as the related ι-carrageenan catabolism pathway. This research provides valuable insights into the enzymatic processes involved in carrageenan catabolism within marine ecological systems.IMPORTANCECarrageenan is a type of linear sulfated polysaccharide that plays a significant role in forming cell walls of marine algae and is found extensively distributed throughout the world's oceans. To the best of our current knowledge, the ι-carrageenan catabolism in marine bacteria either follows the depolymerization-desulfurization sequential process initiated by ι-carrageenase or starts from the desulfurization step catalyzed by exo-acting sulfatases. In this study, we found that the marine bacterium Pseudoalteromonas haloplanktis LL1 processes a distinct pathway for ι-carrageenan catabolism employing a specific endo-acting DA2S-sulfatase PhSulf1 and a multifunctional G4S sulfatase PhSulf2. The unique PhSulf1 homologs appear to be widely present on a global scale, indicating the indispensable contribution of the marine bacteria containing the distinct ι-carrageenan catabolism pathway. Therefore, this study would significantly enrich our understanding of the molecular mechanisms underlying carrageenan utilization, providing valuable insights into the intricate roles of marine bacteria in polysaccharide cycling in marine environments.


Asunto(s)
Proteínas Bacterianas , Carragenina , Pseudoalteromonas , Sulfatasas , Carragenina/metabolismo , Pseudoalteromonas/enzimología , Pseudoalteromonas/genética , Pseudoalteromonas/metabolismo , Sulfatasas/metabolismo , Sulfatasas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Agua de Mar/microbiología
8.
Chemphyschem ; 25(9): e202300973, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38345139

RESUMEN

Bacterial bioluminescence holds significant potential in the realm of optical imaging due to the inherent advantages of bioluminescence and ease of operation. However, its practical utility is hindered by its low light intensity. The fusion of bacterial luciferase with a highly fluorescent protein has been demonstrated to significantly enhance autonomous luminescence. Nevertheless, the underlying mechanism behind this enhancement remains unclear, and there is a dearth of research investigating the mechanistic aspects of bioluminescence resonance energy transfer (BRET) luminescence, whether it occurs naturally or can be achieved through experimental means. In this study, we investigated the phenomenon of bacterial luciferase-based BRET luminescence employing a range of computational techniques, including structural modeling, molecular docking, molecular dynamics simulations, as well as combined quantum mechanics and molecular mechanics calculations. The theoretical findings suggest that the BRET luminescence occurs through resonance energy transfer between the excited bioluminophore and the ground chromophore within the protein complex dimer. The proposed mechanism of the protein complex dimer offers a microscopic understanding of the intriguing BRET phenomenon and has the potential to inspire further practical applications in the field of optical imaging.


Asunto(s)
Simulación de Dinámica Molecular , Luciferasas de la Bacteria/química , Luciferasas de la Bacteria/metabolismo , Luminiscencia , Transferencia de Energía por Resonancia de Bioluminiscencia , Teoría Cuántica , Multimerización de Proteína , Transferencia Resonante de Energía de Fluorescencia , Transferencia de Energía , Simulación del Acoplamiento Molecular , Mediciones Luminiscentes
9.
Langmuir ; 40(22): 11450-11459, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38777791

RESUMEN

The electrooxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA) demonstrated its unique superiority, not only in reducing overpotential and improving energy conversion efficiency for green hydrogen production but also in utilizing abundant biomass resources and producing high-value-added chemicals. However, designing highly efficient electrocatalysts for HMF electrooxidation (HMF-EOR) with low cost and high performance for large-scale production remained a huge challenge. Herein, we introduced an easy one-step activation process to produce P-doped porous biochar loaded with multiple crystal surfaces exposed to CoP2O6 catalysts (CoP2O6@PC), which exhibited outstanding electrooxidation performance. To achieve a current density of 50 mA cm-2, only a low overpotential of 200 mV was needed for the electrooxidation of HMF in 1.0 M KOH + 10 mM HMF. This performance far surpassed that of other similar materials. CoP2O6@PC exhibited outstanding HMF-EOR performance with high conversion (nearly 100%), selectivity (97.1%), faradaic efficiency (95.3%), and robust stability. This work represents a promising strategy to fabricate macroscale and low-cost HMF-EOR electrocatalysts and achieve potential industrial applications of HMF-EOR.

10.
Mol Cell Biochem ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963615

RESUMEN

Gastrointestinal (GI) cancers are a major global health burden, representing 20% of all cancer diagnoses and 22.5% of global cancer-related deaths. Their aggressive nature and resistance to treatment pose a significant challenge, with late-stage survival rates below 15% at five years. Therefore, there is an urgent need to delve deeper into the mechanisms of gastrointestinal cancer progression and optimize treatment strategies. Increasing evidence highlights the active involvement of abnormal arachidonic acid (AA) metabolism in various cancers. AA is a fatty acid mainly metabolized into diverse bioactive compounds by three enzymes: cyclooxygenase, lipoxygenase, and cytochrome P450 enzymes. Abnormal AA metabolism and altered levels of its metabolites may play a pivotal role in the development of GI cancers. However, the underlying mechanisms remain unclear. This review highlights a unique perspective by focusing on the abnormal metabolism of AA and its involvement in GI cancers. We summarize the latest advancements in understanding AA metabolism in GI cancers, outlining changes in AA levels and their potential role in liver, colorectal, pancreatic, esophageal, gastric, and gallbladder cancers. Moreover, we also explore the potential of targeting abnormal AA metabolism for future therapies, considering the current need to explore AA metabolism in GI cancers and outlining promising avenues for further research. Ultimately, such investigations aim to improve treatment options for patients with GI cancers and pave the way for better cancer management in this area.

11.
Cell Biol Toxicol ; 40(1): 52, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967699

RESUMEN

Diabetic osteoporosis (DO) presents significant clinical challenges. This study aimed to investigate the potential of magnetic nanoparticle-enhanced extracellular vesicles (GMNPE-EVs) derived from bone marrow mesenchymal stem cells (BMSCs) to deliver miR-15b-5p, thereby targeting and downregulating glial fibrillary acidic protein (GFAP) expression in rat DO models. Data was sourced from DO-related RNA-seq datasets combined with GEO and GeneCards databases. Rat primary BMSCs, bone marrow-derived macrophages (BMMs), and osteoclasts were isolated and cultured. EVs were separated, and GMNPE targeting EVs were synthesized. Bioinformatic analysis revealed a high GFAP expression in DO-related RNA-seq and GSE26168 datasets for disease models. Experimental results confirmed elevated GFAP in rat DO bone tissues, promoting osteoclast differentiation. miR-15b-5p was identified as a GFAP inhibitor, but was significantly downregulated in DO and enriched in BMSC-derived EVs. In vitro experiments showed that GMNPE-EVs could transfer miR-15b-5p to osteoclasts, downregulating GFAP and inhibiting osteoclast differentiation. In vivo tests confirmed the therapeutic potential of this approach in alleviating rat DO. Collectively, GMNPE-EVs can effectively deliver miR-15b-5p to osteoclasts, downregulating GFAP expression, and hence, offering a therapeutic strategy for rat DO.


Asunto(s)
Vesículas Extracelulares , Proteína Ácida Fibrilar de la Glía , Células Madre Mesenquimatosas , MicroARNs , Osteoclastos , Osteoporosis , Ratas Sprague-Dawley , Animales , MicroARNs/genética , MicroARNs/metabolismo , Células Madre Mesenquimatosas/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Osteoporosis/metabolismo , Osteoporosis/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Proteína Ácida Fibrilar de la Glía/genética , Ratas , Osteoclastos/metabolismo , Masculino , Diferenciación Celular , Nanopartículas de Magnetita , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética , Complicaciones de la Diabetes/metabolismo , Complicaciones de la Diabetes/genética
12.
Environ Sci Technol ; 58(22): 9536-9547, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38771144

RESUMEN

Recent studies found the intrusion and retention of exogenous fine particles into joints, but epidemiological data for long- and intermediate-term exposure associations are scare. Here, all urban working, retired employee, and rural residents (16.78 million) in Beijing from January 1, 2011 to December 31, 2019 were included to investigate the effects of long- and intermediate-term ambient particulate exposure on development of osteoarthritis. We identified 1,742,067 participants as first-visit patients with osteoarthritis. For each interquartile range increase in annual PM2.5 (23.32 µg/m3) and PM10 (23.92 µg/m3) exposure concentration, the pooled hazard ratios were respectively 1.238 (95% CI: 1.228, 1.249) and 1.178 (95% CI: 1.168, 1.189) for first osteoarthritis outpatient visits. Moreover, age at first osteoarthritis outpatient visits significantly decreased by 4.52 (95% CI: 3.45 to 5.40) days per µg/m3 for annual PM2.5 exposure at below 67.85 µg/m3. Finally, among the six constituents analyzed, black carbon appears to be the most important component associated with the association between PM2.5 exposure and the three osteoarthritis-related outcomes.


Asunto(s)
Osteoartritis , Material Particulado , Humanos , Osteoartritis/epidemiología , Estudios Prospectivos , Contaminación del Aire , Masculino , Contaminantes Atmosféricos , Femenino , Exposición a Riesgos Ambientales , Persona de Mediana Edad , Factores de Riesgo , Beijing/epidemiología , Anciano
13.
J Phys Chem A ; 128(28): 5659-5667, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38953788

RESUMEN

Tetrahalogen-1,4-benzoquinone (THBQ) represents a category of H2O2-dependent substrates for chemiluminescence (CL), including tetrafluoro-, tetrachloro-, tetrabromo-, and tetraiodo-1,4-benzoquinone (TFBQ, TCBQ, TBBQ, and TIBQ). A deep understanding of the CL mechanism of THBQ is essential for all H2O2-dependent CL and even some bioluminescence. This article systematically investigates the CL process of THBQ by density functional theory and multireference state theory. The theoretical results confirm the generality of the CL mechanism previously proposed in studies on TCBQ and TBBQ. The dissociation steps producing the emitter of light from dihalogenquinone dioxetane (DHD) and its anion (DHD-), formed by the oxidation of THBQ, were carefully considered. Findings show that the dissociation of DHD/DHD- follows the entropy trap/gradually reversible charge-transfer-induced luminescence (GRCTIL) mechanisms. The dissociation of DHD- is kinetically more advantageous compared with that of DHD. At the practical experimental pH value, the decrease in the electron-withdrawing inductive effect from F to I substituents results in the decrease in the proportions of easily dissociated DHD-, and the increase in the heavy-atom effect from F to I substituents leads to the increase in the phosphorescence emission. These combined factors successively decrease the CL intensity from TFBQ to TCBQ, TBBQ, and TIBQ. The conclusions are verified by the previous experiments on TCBQ and TBBQ, and they are expected to be confirmed by future experiments on TFBQ and TIBQ.

14.
J Sep Sci ; 47(2): e2300802, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38286730

RESUMEN

Polyethylene glycol (PEG) is one of the most commonly used polymers in drug delivery systems. The investigation of the pharmacokinetic behavior of PEG is important for revealing the toxicity and efficiency of PEG-related Nano-drug delivery systems. A high through-put and selective ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method coupled with collision-induced dissociation (CID) in source technique was developed and validated to determine PEG1K polymers in cellular samples in this study. The countless precursor ions of PEG1K are dissociated in the source to generate numerous product ions which have different numbers of subunits. The transition of [M+H]+ precursor ions → product ions at m/z 177.1 (four subunits)→89.1 (two subunits) was selected to determine PEG1K due to its high sensitivity. The UHPLC-MS/MS method coupled with CID in the source showed good linearity over the range of 0.1-10 µg/mL. Intra-day and inter-day accuracies and precisions of the assay were all within ± 12.39%. The assay was successfully applied to a cellular pharmacokinetic study of PEG1K in human breast cancer cells. The cytotoxicity of PEG1K polymers was also studied and the results indicated that the cytotoxicity of PEG1K was not significant in the range of 5-1200 µg/mL.


Asunto(s)
Polímeros , Espectrometría de Masas en Tándem , Humanos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Polímeros/toxicidad , Polímeros/análisis , Polietilenglicoles/química , Iones
15.
BMC Med Imaging ; 24(1): 86, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600525

RESUMEN

Medical imaging AI systems and big data analytics have attracted much attention from researchers of industry and academia. The application of medical imaging AI systems and big data analytics play an important role in the technology of content based remote sensing (CBRS) development. Environmental data, information, and analysis have been produced promptly using remote sensing (RS). The method for creating a useful digital map from an image data set is called image information extraction. Image information extraction depends on target recognition (shape and color). For low-level image attributes like texture, Classifier-based Retrieval(CR) techniques are ineffective since they categorize the input images and only return images from the determined classes of RS. The issues mentioned earlier cannot be handled by the existing expertise based on a keyword/metadata remote sensing data service model. To get over these restrictions, Fuzzy Class Membership-based Image Extraction (FCMIE), a technology developed for Content-Based Remote Sensing (CBRS), is suggested. The compensation fuzzy neural network (CFNN) is used to calculate the category label and fuzzy category membership of the query image. Use a basic and balanced weighted distance metric. Feature information extraction (FIE) enhances remote sensing image processing and autonomous information retrieval of visual content based on time-frequency meaning, such as color, texture and shape attributes of images. Hierarchical nested structure and cyclic similarity measure produce faster queries when searching. The experiment's findings indicate that applying the proposed model can have favorable outcomes for assessment measures, including Ratio of Coverage, average means precision, recall, and efficiency retrieval that are attained more effectively than the existing CR model. In the areas of feature tracking, climate forecasting, background noise reduction, and simulating nonlinear functional behaviors, CFNN has a wide range of RS applications. The proposed method CFNN-FCMIE achieves a minimum range of 4-5% for all three feature vectors, sample mean and comparison precision-recall ratio, which gives better results than the existing classifier-based retrieval model. This work provides an important reference for medical imaging artificial intelligence system and big data analysis.


Asunto(s)
Inteligencia Artificial , Tecnología de Sensores Remotos , Humanos , Ciencia de los Datos , Almacenamiento y Recuperación de la Información , Redes Neurales de la Computación
16.
Curr Microbiol ; 81(2): 64, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38225342

RESUMEN

Soil microbial communities are engineers of important biogeochemical processes and play a critical role in regulating the functions and stability of forest ecosystem. However, few studies have assessed microbial interactions during forest conversion, which is essential to the understanding of the structure and function of soil microbiome. Herein, we investigated the co-occurrence network pattern and putative functions of fungal and bacterial communities in forest-transforming areas (five sites that cover the typical forests) using high-throughput sequencing of the ITS genes and 16S rRNA. Our study showed that the bacterial network had higher average connectivity and more links than fungal network, which might indicate that the bacterial community had more complex internal interactions compared with fungal one. Alphaproteobacteria_unclassfied, Telmatobacter, 0319-6A21 and Latescibacteria_unclassfied were the keystone taxa in bacterial network. For the fungal community network, the keystone taxon was Ceratobasidium. A structural equation model indicated that the available potassium and total organic carbon were important soil environmental factors, which affected all microbial modules, including bacterial and fungi. Total nitrogen had significant effects on the bacterial module that contains a relatively rich group of nitrogen cycling functions, and pH influenced the bacterial module which have higher potential functions of carbon cycling. And, more fungal modules were directly affected by forest structure (S Tree) compared with bacterial ones. This study provides new insights into our understanding of the feedback of underground creatures to forest conversion and highlights the importance of microbial modules in the nutrient cycling process.


Asunto(s)
Ecosistema , Microbiota , Suelo/química , ARN Ribosómico 16S/genética , Microbiología del Suelo , Bosques , Microbiota/genética , Bacterias/genética , Carbono , Nitrógeno/análisis
17.
BMC Public Health ; 24(1): 1465, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822295

RESUMEN

BACKGROUND: Malnutrition is related to impaired oral health and function that causes poor dietary intake, declining the general health of older adults. The role of dietary intake in the association between oral function and nutritional status of Chinese older adults (aged 75 and above) was examined in this cross-sectional study. METHODS: Through the randomized cluster sampling method, 267 older adults living in rural areas of Qingdao, Shandong (aged 81.4 ± 4.3, 75-94 years) were chosen as the primary research participants. A Mini Nutritional Assessment - Short Form was used to determine nutritional status, and Food Frequency Questionnaire and 24-hour Food Intake Recall were used to assess dietary intake. The oral function was evaluated by analyzing the teeth, oral problems, bite force, tongue pressure, lip sealing pressure, chewing function questionnaire, whole saliva flow rate, 10-Item Eating Assessment Tool, and water swallow test. RESULTS: Based on the MNA-SF score, it was divided into a well-nourished group and a malnutrition group, with the malnutrition group comprising 40.6% of participants. The participants in the malnutrition group showed a higher rate of xerostomia, lower bite force, tongue pressure, and lip sealing pressure, and higher Chewing Function Questionnaire and 10-Item Eating Assessment Tool scores. Furthermore, their plant fat, iron, cereals and potatoes, vegetables, fruits, and seafood intake were relatively low. The regression model indicated that exercise frequency, stroke, chewing and swallowing function, intake of vegetables and fruits were risk factors for nutritional status of older adults. CONCLUSION: Malnutrition was relatively common among the Chinese older adults aged 75 and above, and it was significantly correlated with exercise frequency, stroke, chewing and swallowing function, and intake of vegetables and fruits. Therefore, nutrition management should be carried out under the understanding and guidance of the oral function and dietary intake of the older adults.


Asunto(s)
Estado Nutricional , Humanos , Estudios Transversales , Anciano , Masculino , Femenino , Anciano de 80 o más Años , China/epidemiología , Desnutrición/epidemiología , Salud Bucal/estadística & datos numéricos , Dieta/estadística & datos numéricos , Ingestión de Alimentos/fisiología , Encuestas y Cuestionarios , Evaluación Nutricional
18.
J Enzyme Inhib Med Chem ; 39(1): 2290912, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38083866

RESUMEN

Targeting Heat shock protein 90 (HSP90) C-terminus is an important strategy to develop HSP90 inhibitors without inducing heat shock response. The development of C-terminal inhibitors, however, is hampered by a lack of understanding regarding the interaction between the HSP90 C-terminus and the present inhibitors. We collected seven classical and structurally diverse HSP90 C-terminal inhibitors and constructed a ligand-based pharmacophore model. The subsequent virtual screening and structural optimisation led to the identification of 2-heteroarylthio-N-arylacetamides as novel HSP90 C-terminal inhibitors. 9 and 27 exhibited strong antitumour activity in vitro by inhibiting proliferation and inducing apoptosis in multiple cancer cell lines. These compounds disrupted the interaction between HSP90 C-terminus and peptidylprolyl isomerase D, exerting a stronger inhibitory effect than novobiocin. 27 significantly induced the degradation of HSP90 clients without triggering heat shock response. In an in vivo study using 4T1 mice breast cancer models, 9 showed a potent antitumour effect without obvious toxicity.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Animales , Ratones , Farmacóforo , Ligandos , Antineoplásicos/farmacología , Antineoplásicos/química , Proteínas HSP90 de Choque Térmico , Línea Celular Tumoral , Proliferación Celular
19.
Anim Biotechnol ; 35(1): 2337760, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38656923

RESUMEN

Although the knee joint (KNJ) and temporomandibular joint (TMJ) all belong to the synovial joint, there are many differences in developmental origin, joint structure and articular cartilage type. Studies of joint development in embryos have been performed, mainly using poultry and rodents. However, KNJ and TMJ in poultry and rodents differ from those in humans in several ways. Very little work has been done on the embryonic development of KNJ and TMJ in large mammals. Several studies have shown that pigs are ideal animals for embryonic development research. Embryonic day 30 (E30), E35, E45, E55, E75, E90, Postnatal day 0 (P0) and Postnatal day 30 (P30) embryos/fetuses from the pigs were used for this study. The results showed that KNJ develops earlier than TMJ. Only one mesenchymal condensate of KNJ is formed on E30, while two mesenchymal condensates of TMJ are present on E35. All structures of KNJ and TMJ were formed on E45. The growth plate of KNJ begins to develop on E45 and becomes more pronounced from E55 to P30. From E75 to E90, more and more vascular-rich cartilage canals form in the cartilage regions of both joints. The cartilaginous canal of the TMJ divides the condyle into sections along the longitudinal axis of the condyle. This arrangement of cartilaginous canal was not found in the KNJ. The chondrification of KNJ precedes that of TMJ. Ossification of the knee condyle occurs gradually from the middle to the periphery, while that of the TMJ occurs gradually from the base of the mandibular condyle. In the KNJ, the ossification of the articular condyle is evident from P0 to P30, and the growth plate is completely formed on P30. In the TMJ, the cartilage layer of condyle becomes thinner from P0 to P30. There is no growth plate formation in TMJ during its entire development. There is no growth plate formation in the TMJ throughout its development. The condyle may be the developmental center of the TMJ. The chondrocytes and hypertrophic chondrocytes of the growth plate are densely arranged. The condylar chondrocytes of TMJ are scattered, while the hypertrophic chondrocytes are arranged. Embryonic development of KNJ and TMJ in pigs is an important bridge for translating the results of rodent studies to medical applications.


Asunto(s)
Articulación de la Rodilla , Articulación Temporomandibular , Animales , Porcinos/embriología , Articulación Temporomandibular/embriología , Articulación Temporomandibular/crecimiento & desarrollo , Articulación de la Rodilla/embriología , Articulación de la Rodilla/crecimiento & desarrollo , Cartílago Articular/embriología , Cartílago Articular/crecimiento & desarrollo , Femenino , Desarrollo Embrionario/fisiología , Embrión de Mamíferos
20.
Exp Aging Res ; : 1-12, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38357913

RESUMEN

The aim was to examine the diagnostic efficacy of hippocampal subregions volume and texture in differentiating amnestic mild cognitive impairment (MCI) from normal aging changes. Ninety MCI subjects and eighty-eight well-matched healthy controls (HCs) were selected. Twelve hippocampal subregions volume and texture features were extracted using Freesurfer and MaZda based on T1 weighted MRI. Then, two-sample t-test and Least Absolute Shrinkage and Selection Operator (LASSO) regression were developed to select a subset of the original features. Support vector machine (SVM) was used to perform the classification task and the area under the curve (AUC), sensitivity, specificity and accuracy were calculated to evaluate the diagnostic efficacy of the model. The volume features with high discriminative power were mainly located in the bilateral CA1 and CA4, while texture feature were gray-level non-uniformity, run length non-uniformity and fraction. Our model based on hippocampal subregions volume and texture features achieved better classification performance with an AUC of 0.90. The volume and texture of hippocampal subregions can be utilized for the diagnosis of MCI. Moreover, we found that the features that contributed most to the model were mainly textural features, followed by volume. These results may guide future studies using structural scans to classify patients with MCI.

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