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Stable radicals and thermally robust high-spin di- and triradicals have emerged as important organic materials due to their promising applications in diverse fields. New fundamental properties, such as SOMO/HOMO inversion of orbital energies, are explored for the design of new stable radicals, including highly luminescent ones with good photostability. A relation with the singlet-triplet energy gap in the corresponding diradicals is proposed. Thermally robust high-spin di- and triradicals, with energy gaps that are comparable to or greater than a thermal energy at room temperature, are more challenging to synthesize but more rewarding. We summarize a number of high-spin di- and triradicals, based on nitronyl nitroxides that provide a relation between the experimental pairwise exchange coupling constant J/k in the high-spin species vs experimental hyperfine coupling constants in the corresponding monoradicals. This relation allows us to identify outliers, which may correspond to radicals where J/k is not measured with sufficient accuracy. Double helical high-spin diradicals, in which spin density is delocalized over the chiral π-system, have been barely explored, with the sole example of such high-spin diradical possessing alternant π-system with Kekulé resonance form. Finally, we discuss a high-spin diradical with electrical conductivity and derivatives of triangulene diradicals.
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Optically pumped magnetometer magnetoencephalography (OPM-MEG) holds significant promise for clinical functional brain imaging due to its superior spatiotemporal resolution. However, effectively suppressing metallic artifacts, particularly from devices such as orthodontic braces and vagal nerve stimulators remains a major challenge, hindering the wider clinical application of wearable OPM-MEG devices. A comprehensive analysis of metal artifact characteristics from time, frequency, and time-frequency perspectives was conducted for the first time using an OPM-MEG device in clinical medicine. This study focused on patients with metal orthodontics, examining the modulation of metal artifacts by breath and head movement, the incomplete regular sub-Gaussian distribution, and the high absolute power ratio in the 0.5-8 Hz band. The existing metal artifact suppression algorithms applied to SQUID-MEG, such as fast independent component analysis (FastICA), information maximization (Infomax), and algorithms for multiple unknown signal extraction (AMUSE), exhibit limited efficacy. Consequently, this study introduced the second-order blind identification (SOBI) algorithm, which utilized multiple time delays for the component separation of OPM-MEG measurement signals. We modified the time delays of the SOBI method to improve its efficacy in separating artifact components, particularly those in the ultralow frequency range. This approach employs the frequency-domain absolute power ratio, root mean square (RMS) value, and mutual information methods to automate the artifact component screening process. The effectiveness of this method was validated through simulation experiments involving four subjects in both resting and evoked experiments. In addition, the proposed method was also validated by the actual OPM-MEG evoked experiments of three subjects. Comparative analyses were conducted against the FastICA, Infomax, and AMUSE algorithms. Evaluation metrics included normalized mean square error, normalized delta band power error, RMS error, and signal-to-noise ratio, demonstrating that the proposed method provides optimal suppression of metal artifacts. This advancement holds promise for enhancing data quality and expanding the clinical applications of OPM-MEG.
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Artefactos , Magnetoencefalografía , Humanos , Magnetoencefalografía/métodos , Magnetoencefalografía/instrumentación , Adulto , Femenino , Masculino , Algoritmos , Metales , Procesamiento de Señales Asistido por Computador , Adulto Joven , Encéfalo/fisiologíaRESUMEN
INTRODUCTION: Breast cancer ranks second as the most common malignancy globally, after lung cancer. Among the various subtypes of breast cancer, HER2 positive breast cancer (HER2 BC)poses a particularly challenging prognosis due to its heightened invasiveness and metastatic potential. The objective of this study was to construct a composite piezoelectric nanoparticle based on poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) for imaging and treatment of HER2 BC. METHOD: By reshaping the crystal structure of P(VDF-TrFE) piezoelectric nanoparticles, improving hydrophilicity, and incorporating imaging capabilities, we developed piezoelectric composite nanoparticles (PGd@tNBs) that integrate imaging and therapeutic functions. The in vitro characterization encompassed the assessment of piezoelectric properties, hydrophilicity, imaging performance, and therapeutic efficacy of these particles. The targeting and therapeutic effectiveness of PGd@tNBs particles were further validated in the SK-BR3 cell line and subsequently confirmed in HER2-positive tumor-bearing mice. RESULTS: The nanoparticle demonstrated excellent biocompatibility and impressive multimodal imaging performance. Magnetic resonance imaging (MRI) observations revealed significant accumulation of PGd@tNBs particles in the HER2 positive tumor, exhibiting superior contrast-enhanced ultrasound performance compared to traditional ultrasound contrast agents, and small animal in vivo imaging showed that PGd@tNBs particles were primarily excreted through respiration and urinary metabolism. Piezoforce Microscopy characterization highlighted the outstanding piezoelectric properties of PGd@tNBs particles. Upon targeted binding to HER2-BC, ultrasound stimulation influenced the cell membrane potential, leading to reversible electroporation. This, in turn, affected the balance of calcium ions inside and outside the cells and the mitochondrial membrane potential. Following ingestion by cells, PGd@tNBs, when exposed to ultrasound, triggered the generation of reactive oxygen species (ROS), resulting in the consumption of glutathione and superoxide dismutase and achieving sonodynamic therapy. Notably, repeated ultrasound stimulation, post PGd@tNBs particles binding and entry into cells, increased ROS production and elevated the apoptosis rate by approximately 45%. CONCLUSION: In conclusion, the PGd@tNBs particles developed exhibit outstanding imaging and therapeutic efficacy, holding potential for precise diagnosis and personalized treatment of HER2 BC.
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Neoplasias de la Mama , Nanopartículas , Receptor ErbB-2 , Animales , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Humanos , Ratones , Línea Celular Tumoral , Receptor ErbB-2/metabolismo , Nanopartículas/química , Imagen por Resonancia Magnética , Terapia por Ultrasonido/métodos , Ratones Desnudos , Ratones Endogámicos BALB C , Medios de Contraste/química , Apoptosis/efectos de los fármacosRESUMEN
BACKGROUND: Blood stasis constitution in traditional Chinese medicine (TCM) is believed to render individuals more susceptible to metabolic diseases. However, the biological underpinnings of this constitutional imbalance remain unclear. METHODS: This study explored the association between blood stasis constitution, serum metabolic markers including uric acid (UA), high-density lipoprotein cholesterol (HDLC), their ratio (UHR), serum metabolites, and gut microbiota. Clinical data, fecal and serum samples were acquired from 24 individuals with a blood stasis constitution and 80 individuals with a balanced constitution among healthy individuals from Guangdong. Gut microbiota composition analysis and serum metabolomics analysis were performed. RESULTS: Females with a blood stasis constitution had higher UA levels, lower HDLC levels, and higher UHR in serum, suggesting a higher risk of metabolic abnormalities. Analysis of the gut microbiome revealed two distinct enterotypes dominated by Bacteroides or Prevotella. Intriguingly, blood stasis subjects were disproportionately clustered within the Bacteroides-rich enterotype. Metabolomic analysis identified subtle differences between the groups, including lower phenylalanine and higher trimethylaminoacetone levels in the blood stasis. Several differential metabolites displayed correlations with HDLC, UA, or UHR, unveiling potential new markers of metabolic dysregulation. CONCLUSIONS: These findings elucidate the intricate interplay between host constitution, gut microbiota, and serum metabolites. The concept of blood stasis offers a unique perspective to identify subtle alterations in microbiome composition and metabolic pathways, potentially signaling underlying metabolic vulnerability, even in the presence of ostensibly healthy profiles. Continued investigation of this TCM principle may reveal critical insights into the early biological processes that foreshadow metabolic deterioration.
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Medicina Tradicional China , Ácido Úrico , Humanos , Femenino , HDL-Colesterol , Heces , Metabolómica , BiomarcadoresRESUMEN
This study prepared sulfonated Camellia oleifera shell biochar using Camellia oleifera shell agricultural waste as a carbon source, and evaluated its performance as a catalyst for preparing biodiesel. The biochar obtained from carbonizing Camellia oleifera shells at 500 °C for 2 h serves as the carbon skeleton, and then the biochar is sulfonated with chlorosulfonic acid. The sulfonic acid groups are mainly grafted onto the surface of Camellia oleifera shell biochar through covalent bonding to obtain sulfonic acid type biochar catalysts. The catalysts were characterized by Scanning Electron Microscope (SEM), X-ray diffraction (XRD), Nitrogen adsorption-desorption Brunel-Emmett-Taylor Theory (BET), and Fourier-transform infrared spectroscopy (FT-IR). The acid density of the sulfonated Camellia oleifera fruit shell biochar catalyst is 2.86 mmol/g, and the specific surface area is 2.67 m2/g, indicating high catalytic activity. The optimal reaction conditions are 4 wt% catalyst with a 6:1 alcohol to oil ratio. After esterification at 70 °C for 2 h, the yield of biodiesel was 91.4%. Under the optimal reaction conditions, after four repeated uses of the catalyst, the yield of biodiesel still reached 90%. Therefore, sulfonated Camellia oleifera shell biochar is a low-cost, green, non-homogeneous catalyst with great potential for biodiesel production by esterification reaction in future development.
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Biocombustibles , Camellia , Carbón Orgánico , Camellia/química , Carbón Orgánico/química , Catálisis , Ácidos Sulfónicos/química , Espectroscopía Infrarroja por Transformada de Fourier , Esterificación , Difracción de Rayos XRESUMEN
BACKGROUND: MiR-381 can regulate the expression of cyclin A2 (CCNA2) to inhibit the proliferation and migration of bladder cancer cells, but whether miR-381 has the same function in breast cancer is not well know. METHODS: The over express or silence miR-381 expressing cell lines were constructed by lentivirus infection to reveal the biological functions of miR-381 in vitro. The expression of miR-381 and CCNA2 in 162 breast cancer patients were detected to further reveal their impact and predictive value on progression-free survival (PFS) and overall survival (OS). RESULTS: After transfection of MDA-MB-231 and MCF-7 cells with miR-381 mimics, the expression of miR-381 was effectively up-regulated and CCNA2 was effectively down-regulated, while the opposite results were observed in tumour cell which transfected with miR-381 inhibitors. After transfection of cell lines with miR-381 mimics, tumour cell activity was significantly reduced, while the opposite results were observed in tumour cell which transfected with miR-381 inhibitors. The area under curves (AUCs) of miRNA-381 and CCNA2 for predicting PFS and OS were 0.711, 0.695, 0.694 and 0.675 respectively. Cox regression analysis showed that miRNA-381 ≥ 1.65 2-ΔΔCt and CCNA ≥ 2.95 2-ΔΔCt were the influence factors of PFS and OS, the hazard ratio (HR) values were 0.553, 2.075, 0.462 and 2.089, respectively. CONCLUSION: miR-381 inhibitors breast cancer cells proliferation and migration by down-regulating the expression of CCNA2, both of them can predict the prognosis of breast cancer.
miR-381 can regulate the expression of cyclin A2 and inhibit the proliferation and migration of bladder cancer cells, but whether miR-381 has the same function in breast cancer is not well know. We analysed the levels of miR-381 and cyclin A2 in breast cancer patients and breast cancer cells to reveal the mechanism of miR-381 affecting the expression of cyclin A2. We found miRNA-381 affects the proliferation and migration of breast cancer cells by down-regulating the expression of cyclin A2. The expression of serum miR-381 and cyclin A2 have important values in predicting the prognosis of breast cancer. Our findings provide mechanistic insights into how miR-381 regulates the proliferation and migration of breast cancer, as well as a new target for clinical treatment. Future research may focus on how to improve patient prognosis by up-regulating expression of miR-381 and down-regulating the expression of cyclin A2.
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Neoplasias de la Mama , Proliferación Celular , Ciclina A2 , Regulación Neoplásica de la Expresión Génica , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/mortalidad , Proliferación Celular/genética , Ciclina A2/genética , Ciclina A2/metabolismo , Pronóstico , Persona de Mediana Edad , Línea Celular Tumoral , Células MCF-7 , AdultoRESUMEN
INTRODUCTION: A prospective observational study was modified to assess the efficacy of surgery alone for the treatment of locally advanced oral squamous cell carcinoma. (LA-OSCC) MATERIALS AND METHODS: This prospective, single-institution, single-arm study involved 174 patients who underwent major surgery for LA-OSCC. Participating patients did not receive postoperative radiation. After initial curative treatment, patients were routinely monitored via clinical examination and imaging. The follow-up period was 3-70 months. Tumour recurrence and death were considered as the Clinical End Point in Research. RESULTS: The 5-year overall survival (OS), disease-free survival (DFS), and locoregional control rates for 174 patients were 66.7% (95% confidence interval [CI], 59.8 to 73.6), 66.1% (95% CI, 59.2 to 73.0), and 82.4% (95% CI, 76.5 to 88.3), respectively. CONCLUSION: A study of patients with LA-OSCC treated with surgery alone may have the optimal therapeutic impact for LA-OSCC, as evidenced by solid data for our next RCT trial. This conclusion still needs to be validated in higher-level RCTs.
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Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Carcinoma de Células Escamosas/cirugía , Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/cirugía , Carcinoma de Células Escamosas de Cabeza y Cuello , Estudios Prospectivos , Recurrencia Local de Neoplasia/patologíaRESUMEN
Open-shell organic molecules, including S = 1/2 radicals, may provide enhanced properties for several emerging technologies; however, relatively few synthesized to date possess robust thermal stability and processability. We report the synthesis of S = 1/2 biphenylene-fused tetrazolinyl radicals 1 and 2. Both radicals possess near-perfect planar structures based on their X-ray structures and density-functional theory (DFT) computations. Radical 1 possesses outstanding thermal stability as indicated by the onset of decomposition at 269 °C, based on thermogravimetric analysis (TGA) data. Both radicals possess very low oxidation potentials <0 V (vs. SCE) and their electrochemical energy gaps, Ecell ≈ 0.9 eV, are rather low. Magnetic properties of polycrystalline 1 are characterized by superconducting quantum interference device (SQUID) magnetometry revealing a one-dimensional S = 1/2 antiferromagnetic Heisenberg chain with exchange coupling constant J'/k ≈ -22.0 K. Radical 1 in toluene glass possesses a long electron spin coherence time, Tm ≈ 7 µs in the 40-80 K temperature range, a property advantageous for potential applications as a molecular spin qubit. Radical 1 is evaporated under ultrahigh vacuum (UHV) forming assemblies of intact radicals on a silicon substrate, as confirmed by high-resolution X-ray photoelectron spectroscopy (XPS). Scanning electron microscope (SEM) images indicate that the radical molecules form nanoneedles on the substrate. The nanoneedles are stable for at least 64 hours under air as monitored by using X-ray photoelectron spectroscopy. Electron paramagnetic resonance (EPR) studies of the thicker assemblies, prepared by UHV evaporation, indicate radical decay according to first-order kinetics with a long half-life of 50 ± 4 days at ambient conditions.
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We report complex formation between the chloroacetamide 2,6-diazaadamantane nitroxide radical (ClA-DZD) and cucurbit[7]uril (CB-7), for which the association constant in water, Ka = 1.9 × 106 M-1, is at least 1 order of magnitude higher than the previously studied organic radicals. The radical is highly immobilized by CB-7, as indicated by the increase in the rotational correlation time, τrot, by a factor of 36, relative to that in the buffer solution. The X-ray structure of ClA-DZD@CB-7 shows the encapsulated DZD guest inside the undistorted CB-7 host, with the pendant group protruding outside. Upon addition of CB-7 to T4 Lysozyme (T4L) doubly spin-labeled with the iodoacetamide derivative of DZD, we observe the increase in τrot and electron spin coherence time, Tm, along with the narrowing of interspin distance distributions. Sensitivity of the DEER measurements at 83 K increases by a factor 4-9, compared to the common spin label such as MTSL, which is not affected by CB-7. Interspin distances of 3 nm could be reliably measured in water/glycerol up to temperatures near the glass transition/melting temperature of the matrix at 200 K, thus bringing us closer to the goal of supramolecular recognition-enabled long-distance DEER measurements at near physiological temperatures. The X-ray structure of DZD-T4L 65 at 1.12 Å resolution allows for unambiguous modeling of the DZD label (0.88 occupancy), indicating an undisturbed structure and conformation of the protein.
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Proteínas , Agua , Marcadores de Spin , Espectroscopía de Resonancia por Spin del Electrón , Agua/químicaRESUMEN
INTRODUCTION: The role of submucosal injection during cold snare polypectomy (CSP) remains uncertain. In this study, we investigated the impact of submucosal saline injection during CSP for colorectal polyps sized 3-9 mm. METHODS: This was a multicenter randomized controlled trial conducted in 6 Chinese centers between July and September 2020 (ChiCTR2000034423). Patients with nonpedunculated colorectal polyps sized 3-9 mm were randomized in a 1:1 ratio to either CSP with submucosal injection (SI-CSP) or conventional CSP (C-CSP). The primary outcome was the incomplete resection rate (IRR). Secondary outcomes included procedure time, intraprocedural bleeding, delayed bleeding, and perforation. RESULTS: One hundred fifty patients with 234 polyps in the SI-CSP group and 150 patients with 216 polyps in the C-CSP group were included in the analysis. The IRR was not decreased in the SI-CSP group compared with that in the C-CSP group (1.7% vs 1.4%, P = 1.000). The median procedure time in the SI-CSP group was significantly longer than that in the C-CSP group (108 seconds vs 48 seconds, P < 0.001). The incidences of intraprocedural bleeding and delayed bleeding were not significantly different between the 2 groups ( P = 0.531 and P = 0.250, respectively). There was no perforation in either group. DISCUSSION: Submucosal saline injection during CSP for colorectal polyps sized 3-9 mm did not decrease the IRR or reduce adverse events but prolonged the procedure time.
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Pólipos del Colon , Neoplasias Colorrectales , Humanos , Pólipos del Colon/complicaciones , Colonoscopía/métodos , Microcirugia/efectos adversos , Hemorragia Posoperatoria/epidemiología , Hemorragia Posoperatoria/etiología , Neoplasias Colorrectales/etiologíaRESUMEN
Mitophagy modulators are proposed as potential therapeutic intervention that enhance neuronal health and brain homeostasis in Alzheimer's disease (AD). Nevertheless, the lack of specific mitophagy inducers, low efficacies, and the severe side effects of nonselective autophagy during AD treatment have hindered their application. In this study, the P@NB nanoscavenger is designed with a reactive-oxygen-species-responsive (ROS-responsive) poly(l-lactide-co-glycolide) core and a surface modified with the Beclin1 and angiopoietin-2 peptides. Notably, nicotinamide adenine dinucleotide (NAD+ ) and Beclin1, which act as mitophagy promoters, are quickly released from P@NB in the presence of high ROS levels in lesions to restore mitochondrial homeostasis and induce microglia polarization toward the M2-type, thereby enabling it to phagocytose amyloid-peptide (Aß). These studies demonstrate that P@NB accelerates Aß degradation and alleviates excessive inflammatory responses by restoring autophagic flux, which ameliorates cognitive impairment in AD mice. This multitarget strategy induces autophagy/mitophagy through synergy, thereby normalizing mitochondrial dysfunction. Therefore, the developed method provides a promising AD-therapy strategy.
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Enfermedad de Alzheimer , Ratones , Animales , Enfermedad de Alzheimer/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Mitofagia , Péptidos beta-Amiloides/metabolismo , Beclina-1RESUMEN
Metal oxides with diverse compositions and structures have garnered considerable interest from researchers in various reactions, which benefits from transmission electron microscopy (TEM) in determining their morphologies, phase, structural and chemical information. Recent breakthroughs have made liquid-phase TEM a promising imaging platform for tracking the dynamic structure, morphology, and composition evolution of metal oxides in solution under work conditions. Herein, this review introduces the recent advances in liquid cells, especially closed liquid cell chips. Subsequently, the recent progress including particle growth, phase transformation, self-assembly, core-shell nanostructure growth, and chemical etching are introduced. With the late technical advances in TEM and liquid cells, liquid-phase TEM is used to characterize many fundamental processes of metal oxides for CO2 reduction and water-splitting reactions. Finally, the outlook and challenges in this research field are discussed. It is believed this compilation inspires and stimulates more efforts in developing and utilizing in situ liquid-phase TEM for metal oxides at the atomic scale for different applications.
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The development of room-temperature chemiresistive gas sensors with low limit of detection, high sensitivity, and selectivity for dimethyl methylphosphonate (DMMP) detection remains a challenge. Herein, a synergy of the two intermolecular hydrogen bond-promoted approach was proposed to fabricate a room-temperature DMMP sensor with enhanced performances. As a proof of concept, ternary p-hexafluoroisopropanol phenyl (HFIP) functionalized polypyrrole-reduced graphene oxide hybrids (HFIP-PPy-rGO) were rationally designed. During the sensing process, rGO serves as a conductive carrier, ensuring that the sensors operate at room temperature, and both HFIP and PPy act as adsorption sites for DMMP through hydrogen bonding interactions. As expected, the HFIP-PPy-rGO sensor exhibits high selectivity and sensitivity to DMMP. Besides, the HFIP-PPy-rGO sensor also possesses excellent linear response to DMMP and long-term stability. Experimental results and quartz crystal microbalance measurements prove that the specific recognition of DMMP is realized by forming two intermolecular hydrogen bonds between HFIP and DMMP, as well as PPy and DMMP. Additionally, the introduction of HFIP groups also contributes to adjusting device conductivity, enhancing signal conversion function. To put the DMMP sensor into potential practical application, the obvious sensing response to different DMMP concentrations in soil was confirmed, and a wireless detection system was built to realize real-time monitoring of DMMP concentrations in the surroundings. Overall, this study provides a facile and practical solution for improving the sensing performance of room-temperature sensors based on the hydrogen bond theory.
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Expansins are cell-wall loosening proteins involved in plant cell expansion and elongation. Objectives of this study were to identify expansins related to leaf elongation in a perennial grass species and determine the relationship between the expression of expansin genes and leaf elongation. A total of 20 expansin genes were identified in tall fescue (Festuca arundinacea), out of which nine genes belonged to the EXPA- and 11 to the EXPB subfamily. Two genotypes ("TF007" and "TF116") with different growth rates were used to determine the correlation between expansins and leaf growth. Among the 20 expansins, 16 were differentially expressed in the leaf growth zone in "TF007" and "TF116." The further analysis of gene expression in different leaf segments of "TF007" and "TF116" revealed that the expression level of FaEXPB16 was positively correlated with leaf elongation rate, and "TF007" had a higher leaf elongation rate than "TF116" due to the greater expression level of FaEXPB16. FaEXPA7 exhibited significantly higher expression level in leaves of the rapid-growing genotypes than the slow-growing genotypes, suggesting that FaEXPA7 acts as a positive regulator for leaf elongation. FaEXPA7 also exhibited its highest expression level in the cell division zone located in the leaf base. FaEXPB3, FaEXPB4-2, and FaEXPB11-2 showed a negative correlation with the leaf elongation rate in "TF007" and "TF116" and were highly expressed in leaves of the slow-growing genotypes. As promoting or repressing factors for leaf growth, these five expansins could be used as candidate genes in developing the rapid or slow-growing perennial grass species.
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Festuca , Lolium , Poaceae/genética , Lolium/metabolismo , Genotipo , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismoRESUMEN
Dollar spot (DS) is a destructive fungal disease impacting almost all warm- and cool-season turfgrasses worldwide. Multiple fungal species in the genus Clarireedia are causal agents of DS. Here, we present whole-genome assemblies of nine fungal isolates in the genus Clarireedia, including four species (C. paspali, C. hainanense, C. jacksonii, and C. monteithiana) causing DS on seashore paspalum (Paspalum vaginatum Sw.), creeping bentgrass (Agrostis stolonifera L.), and Kentucky bluegrass (Poa pratensis L.) in China. This work provides valuable baseline genomic data to support further research and management of DS pathogens on turfgrasses.
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Agrostis , Ascomicetos , Poa , Ascomicetos/genética , Agrostis/genética , Agrostis/microbiología , Genómica , ChinaRESUMEN
Hybrid bermudagrass (Cynodon dactylon × C. transvaalensis) is widely used as turf in southern and transition zones of China. From June to September in 2022, an unknown disease was consistently observed on hybrid bermudagrass in different regions of Nanjing China, exhibiting distinct symptoms of leaf necrosis, severe root rot and circular or irregular necrotic patches with 20-300 cm in diameter. In this study, culture -independent and dependent methods were used to elucidate the dominant fungal pathogens associated with the disease. Basidiomycota and Marasmiellus were shown to be the dominant phyla (51.96%-70.60%) and genera (50.09%-69.84%) in the symptomatic samples. A total of 128 fungal strains were isolated from symptomatic root tissues, and 40 strains representing the largest proportion (31.25%), were identified as Marasmiellus mesosporus, based on the morphological characteristics, phylogenetic analysis of ITS and LSU rDNA region, and pathogenicity testing. Temperature sensitivity tests revealed that M. mesosporus grew well at high temperature (growth rate of 13.74 mm/d at 36 â). To our knowledge, this is the first report of M. mesosporus causing root rot disease on hybrid bermudagrass during hot summer months. The study will have important implications for the management of the disease.
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Dollar spot (DS), caused by Clarireedia spp. (formerly Sclerotinia homoeocarpa), is one of the most important diseases of turfgrasses worldwide. Benzovindiflupyr, a pyrazole carboxamide fungicide belonging to succinate dehydrogenase inhibitors, was recently registered for DS control. In this study, baseline sensitivity, toxicity, and control efficacy of benzovindiflupyr against Clarireedia spp. were evaluated. The frequency of sensitivities had a unimodal distribution (Kolmogorov-Smirnov, P > 0.10). The mean EC50 value was 1.109 ± 0.555 µg/ml, with individual values ranging from 0.160 to 2.548 µg/ml. Benzovindiflupyr increased the number of hyphal offshoots and cell membrane permeability and inhibited oxalic acid production. Positive cross-resistance was observed between benzovindiflupyr and boscalid, but not between benzovindiflupyr and thiophanate-methyl, propiconazole, or iprodione. Benzovindiflupyr showed high protective and curative control efficacies in vivo and in field applications. Both protective and curative control efficacies of benzovindiflupyr were significantly better than propiconazole, and equivalent to boscalid, over 2 years of field research. The results have important implications for managing DS and fungicide resistance problems in Clarireedia spp.
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Ascomicetos , Fungicidas Industriales , Fungicidas Industriales/farmacología , Ácido Succínico , Succinato Deshidrogenasa , Pirazoles/farmacología , SuccinatosRESUMEN
The use of organic fertilizer for agricultural production can reduce the use of chemical fertilizer (CF), reduce greenhouse gas emissions, and maintain crop production. However, biogas slurry (BS), a liquid with a high moisture content and a low C/N ratio, differs from commercial organic fertilizer and manure in terms of its impact on the soil N cycle. Replacing CF with BS needs to be reconsidered regarding soil nitrous oxide (N2O) emissions and crop production in terms of fertilization, agricultural land type, and soil characteristics. For this systematic review, the results of 92 published studies worldwide were collected. Based on the findings, the combined application of BS and CF can significantly increase soil total N (TN), microbial biomass N (MBN), and soil organic matter (SOM) levels. The Chaol and ACE index values of soil bacteria were increased by 13.58% and 18.53%, whereas those of soil fungi were decreased by 10.45% and 14.53%, respectively. At a replacement ratio (rr) ≤ 70%, crop yield was promoted by 2.20%-12.17%, and soil N2O emissions were reduced by 1.94%-21.81%. A small rr (≤30%) was more conducive to growth, and a moderate rr (30% < rr ≤ 70%) was more favorable for N2O emission reduction, especially in the dryland crop system. However, at rr = 100%, soil N2O emissions in neutral and alkaline dryland soil were increased by 28.56%-32.22%. The importance analysis of the influencing factors showed that the proportion of BS, the N application rate, and the temperature were the factors affecting soil N2O emissions. Our results provide a scientific basis for the safe use of BS in agricultural systems.
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Biocombustibles , Suelo , Suelo/química , Biocombustibles/análisis , Fertilizantes/análisis , Agricultura/métodos , Óxido Nitroso/análisis , Nitrógeno/análisis , ChinaRESUMEN
The aim of this Policy Review was to compare China's overall and synchronous participation in clinical trials for innovative anticancer drugs with that of the USA, the EU, Japan, and South Korea, and to assess changes in the participation rate trends in these five regions. Relevant data from the top 20 international pharmaceutical companies from 2011 to 2021 were systematically collected from the Trialtrove and Pharmaprojects databases. Among the 8260 trials for 954 new anticancer drugs identified, China was involved in 8·8% of the trials and with 20·4% of the drugs being trialled. These participation rates are significantly lower than those for South Korea (14·5% of trials and 36·3% of drugs), Japan (16·1% of trials and 38·7% of drugs), the EU (40·6% of trials and 67·7% of drugs), and the USA (65·7% of trials and 91·2% of drugs; p<0·0001 for all). Similar results were found for the synchronous participation rate, defined as the proportion of drugs or trials at the highest development stage internationally, for the 803 tested drugs, which ranged from 9·0% in China to 87·7% in the USA. China's participation rate in early phase trials (4·4%) and in synchronous trials (5·4%) was even lower, in stark contrast to that of the USA (66·1% for early phase trials and 89·1% for synchronous trials). The fastest growing annual rate of participation in trials was observed in China (15·7%), followed by South Korea (8·2%) and Japan (6·8%); no change was detected in the USA or the EU. This Policy Review shows that Chinese participation in the clinical development of innovative cancer drugs by international pharmaceutical companies has increased over the past decade, but an obvious gap persists in comparison with the USA, the EU, Japan, and South Korea, especially in its synchronous participation and early participation rates.
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Antineoplásicos , Humanos , Antineoplásicos/uso terapéutico , China , Japón , República de Corea/epidemiología , Industria FarmacéuticaRESUMEN
BACKGROUND: The chloroplast is the organelle responsible for photosynthesis in higher plants. The generation of functional chloroplasts depends on the precise coordination of gene expression in the nucleus and chloroplasts and is essential for the development of plants. However, little is known about nuclear-plastid regulatory mechanisms at the early stage of chloroplast generation in rice. RESULTS: In this study, we identified a rice (Oryza sativa) mutant that exhibited albino and seedling-lethal phenotypes and named it ssa1(seedling stage albino1). Transmission electron microscopy (TEM) analysis indicated that the chloroplasts of ssa1 did not have organized thylakoid lamellae and that the chloroplast structure was destroyed. Genetic analysis revealed that the albino phenotypes of ssa1 were controlled by a pair of recessive nuclear genes. Map-based cloning experiments found that SSA1 encoded a pentapeptide repeat (PPR) protein that was allelic to OSOTP51,which was previously reported to participate in Photosystem I (PSI) assembly. The albino phenotype was reversed to the wild type (WT) phenotype when the normal SSA1 sequence was expressed in ssa1 under the drive of the actin promoter. Knockout experiments further created mutants ssa1-2/1-9, which had a phenotype similar to that of ssa1. SSA1 consisted of 7 pentatricopeptide repeat domains and two C-terminal LAGLIDADG tandem sequence motifs and was located in the chloroplast. GUS staining and qRT-PCR analysis showed that SSA1 was mainly expressed in young leaves and stems. In the ssa1 mutants, plastid genes transcribed by plastid-encoded RNA polymerase decreased, while those transcribed by nuclear-encoded RNA polymerase increased at the mRNA level. Loss-of-function SSA1 destroys RNA editing of ndhB-737 and intron splicing of atpF and ycf3-2 in the plastid genome. Yeast two-hybrid and BiFC assays revealed that SSA1 physically interacted with two new RNA editing partners, OsMORF8 and OsTRXz, which have potential functions in RNA editing and chloroplast biogenesis. CONCLUSIONS: Rice SSA1 encodes a pentatricopeptide repeat protein, which is targeted to the chloroplast. SSA1 regulates early chloroplast development and plays a critical role in RNA editing and intron splicing in rice. These data will facilitate efforts to further elucidate the molecular mechanism of chloroplast biogenesis.