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1.
Plant Biotechnol J ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578842

RESUMO

Potassium (K+) plays a crucial role as a macronutrient in the growth and development of plants. Studies have definitely determined the vital roles of K+ in response to pathogen invasion. Our previous investigations revealed that rice plants infected with rice grassy stunt virus (RGSV) displayed a reduction in K+ content, but the mechanism by which RGSV infection subverts K+ uptake remains unknown. In this study, we found that overexpression of RGSV P1, a specific viral protein encoded by viral RNA1, results in enhanced sensitivity to low K+ stress and exhibits a significantly lower rate of K+ influx compared to wild-type rice plants. Further investigation revealed that RGSV P1 interacts with OsCIPK23, an upstream regulator of Shaker K+ channel OsAKT1. Moreover, we found that the P1 protein recruits the OsCIPK23 to the Cajal bodies (CBs). In vivo assays demonstrated that the P1 protein competitively binds to OsCIPK23 with both OsCBL1 and OsAKT1. In the nucleus, the P1 protein enhances the binding of OsCIPK23 to OsCoilin, a homologue of the signature protein of CBs in Arabidopsis, and facilitates their trafficking through these CB structures. Genetic analysis indicates that mutant in oscipk23 suppresses RGSV systemic infection. Conversely, osakt1 mutants exhibited increased sensitivity to RGSV infection. These findings suggest that RGSV P1 hinders the absorption of K+ in rice plants by recruiting the OsCIPK23 to the CB structures. This process potentially promotes virus systemic infection but comes at the expense of inhibiting OsAKT1 activity.

2.
Environ Res ; 252(Pt 3): 118936, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38657847

RESUMO

Artificial forest restoration is widely recognized as a crucial approach to enhance the potential of soil carbon sequestration. Nevertheless, there is still limited understanding regarding the dynamics of aggregate organic carbon (OC) and the underlying mechanisms driving these dynamics after artificial forest restoration. To address this gap, we studied Pinus tabuliformis forests and adjacent farmland in three recovery periods (13, 24 and 33 years) in the Loess Plateau region. Samples of undisturbed soil from the surface layer were collected and divided into three aggregate sizes: >2 mm (large aggregate), 0.25-2 mm (medium aggregate), and <0.25 mm (small aggregate). The aim was to examine the distribution of OC and changes in enzyme activity within each aggregate size. The findings revealed a significant increase in OC content for all aggregate sizes following the restoration of Pinus tabuliformis forests. After 33 years of recovery, the OC of large aggregates, medium aggregates and micro-aggregates increased by (30.23 ± 9.85)%, (36.71 ± 21.60)% and (37.88 ± 16.07)% respectively compared with that of farmland. Moreover, the restoration of Pinus tabuliformis forests lead to increased activity of hydrolytic enzymes and decreased activity of oxidative enzymes. It is noteworthy that the regulation of carbon in all aggregates is influenced by soil P-limitation. In large aggregates, P-limitation promotes the enhancement of hydrolytic enzyme activity, thereby facilitate OC accumulation. Conversely, in medium and small aggregates, P-limitation inhibits the increase in oxidative enzyme activity, resulting in OC accumulation. The results emphasize the importance of P-limitation in regulating OC accumulation during the restoration of Pinus tabulaeformis forest, in which large aggregates play a leading role.


Assuntos
Carbono , Florestas , Pinus , Solo , Solo/química , Carbono/análise , Carbono/metabolismo , Sequestro de Carbono , China
3.
Altern Ther Health Med ; 30(2): 140-145, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37856805

RESUMO

Objective: The state of nutrition of senior patients with intertrochanteric fracture of femur before operation affects the patients' tolerance to the operation,the body recovery, healing of the wound and clinical prognosis. For these patients, the poor state of nutrition may lengthen the time of being in hospital, leading to poor hip recovery and clinical outcome. But currently, the relationship between functional recovery of hip joint after operation of intertrochanteric fracture in elderly patients and camp condition has not been reported. To investigate the effect of preoperative nutritional status on postoperative recovery of hip joint function in elderly patients with intertrochanteric fractures. Methods: Retrospective analysis was performed on the data of 96 elderly patients with intertrochanteric fracture of the femur treated with closed reduction PFNAfrom January 2021 to January 2022 in Dongying People's Hospital Trauma Orthopedics Department. There were 36 male patients and 60 female patients aged from 65 to 92.The patients were divided into the normal nutrition group (GNRI ≥ 92, n = 46) and the malnutrition group (GNRI < 92, n = 50). The general clinical data, time from injury to operation, intraoperative and postoperative allogeneic blood transfusion rate, postoperative complication rate, postoperative mortality 1 year, and Harris hip function score at 3, 6, 9 months and the last follow-up were compared between the two groups. Results: All patients were followed up for 9 to 15 months(mean,13.9 months) after surgery. The preoperative hemoglobin levels in the normal and malnutrition groups were 8.6-13.2 and 7.4-11.2 g/dL, respectively (P < .05). The time from injury to surgery in the normal nutrition group was significantly shorter than that in the malnutrition group (P < .01). The preoperative hemoglobin level in the normal nutrition group was significantly higher than that in the malnutrition group. The time from injury to operation in normal nutrition group and malnutrition group are respectively (1.1-5.2), (4.3-6.6)d; the intraoperative and postoperative allogeneic blood transfusion rates are respectively 47.8%(22/46), 92%(46/50);the incidence of postoperative complications are respectively 6.52%(3/46), 32%(16/50); the mortality rates within 1 year after operation are respectively 2.17%(1/46), 12%(6/50). In contrast, the postoperative allogeneic blood transfusion, postoperative complication, and postoperative complication rates in the normal nutrition group were significantly lower than those in the malnutrition group (P < .05). 3 months after surgery, the Harris hip function scores of patients in normal nutrition group and malnutrition group are respectively (75.26±4.02), (64.28±3.82); 6 months after surgery, the Harris hip function scores of them are respectively (80.42±3.86), (70.14±5.06).During the last follow-up, scores are (82.23±2.98), (72.12±4.62). At the 3, 6, and last follow-up after surgery, the Harris hip function score in the normal nutrition group was significantly higher than in the malnutrition group (P < .05). Conclusion: Preoperative malnutrition in elderly patients with intertrochanteric fracture has adverse effects on postoperative hip function recovery, and 1-year postoperative survival rate.GNRI can be used for simple screening. Early assessment of patients' nutritional status.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Desnutrição , Humanos , Masculino , Feminino , Idoso , Estudos Retrospectivos , Estado Nutricional , Recuperação de Função Fisiológica , Resultado do Tratamento , Pinos Ortopédicos , Fraturas do Quadril/cirurgia , Complicações Pós-Operatórias/epidemiologia , Articulação do Quadril/cirurgia , Hemoglobinas
4.
Sensors (Basel) ; 24(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38894400

RESUMO

Dynamic liquid level monitoring and measurement in oil wells is essential in ensuring the safe and efficient operation of oil extraction machinery and formulating rational extraction policies that enhance the productivity of oilfields. This paper presents an intelligent infrasound-based measurement method for oil wells' dynamic liquid levels; it is designed to address the challenges of conventional measurement methods, including high costs, low precision, low robustness and inadequate real-time performance. Firstly, a novel noise reduction algorithm is introduced to effectively mitigate both periodic and stochastic noise, thereby significantly improving the accuracy of dynamic liquid level detection. Additionally, leveraging the PyQT framework, a software platform for real-time dynamic liquid level monitoring is engineered, capable of generating liquid level profiles, computing the sound velocity and liquid depth and visualizing the monitoring data. To bolster the data storage and analytical capabilities, the system incorporates an around-the-clock unattended monitoring approach, utilizing Internet of Things (IoT) technology to facilitate the transmission of the collected dynamic liquid level data and computed results to the oilfield's central data repository via LoRa and 4G communication modules. Field trials on dynamic liquid level monitoring and measurement in oil wells demonstrate a measurement range of 600 m to 3000 m, with consistent and reliable results, fulfilling the requirements for oil well dynamic liquid level monitoring and measurement. This innovative system offers a new perspective and methodology for the computation and surveillance of dynamic liquid level depths.

5.
Angew Chem Int Ed Engl ; 63(28): e202404477, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38669345

RESUMO

Intermolecular pnictogen bonding (PnB) catalysis has received increased interest in non-covalent organocatalysis. It has been demonstrated that organic electron-deficient pnictogen atoms can act as prospective Lewis acids. Here, we present a catalytic approach for the asymmetric synthesis of chiral PIII compounds by combining intramolecular PnB interactions and carbene catalysis. Our design features a pre-chiral phosphorus molecule bearing two electron-withdrawing benzoyl groups, resulting in the formation of a σ-hole at the P atom. X-ray and non-covalent interaction (NCI) analysis indicate that the model substrates exhibit intrinsic PnB interaction between the oxygen atom of the formyl group and the phosphorus atom. This induces a conformational locking effect, leading to the crystallization of the phosphorus substrate in a preferred conformation (P212121 chiral group). Under the catalysis of N-heterocyclic carbene, the aldehyde moiety activated by the pnictogen bond selectively reacts with an alcohol to yield the corresponding chiral monoester/phosphorus product with excellent enantioselectivity. This Lewis acidic phosphorus center, aroused by the non-polarized intramolecular pnictogen bond interaction, assists in conformational and selective regulations, providing unique opportunities for catalysis and beyond.

6.
BMC Genomics ; 24(1): 158, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991328

RESUMO

BACKGROUND: Ammonium (NH4+) is a key nitrogen source supporting plant growth and development. Proteins in the ammonium transporter (AMT) family mediate the movement of NH4+ across the cell membrane. Although several studies have examined AMT genes in various plant species, few studies of the AMT gene family have been conducted in chili pepper. RESULTS: Here, a total of eight AMT genes were identified in chili pepper, and their exon/intron structures, phylogenetic relationships, and expression patterns in response to arbuscular mycorrhizal (AM) colonization were explored. Synteny analyses among chili pepper, tomato, eggplant, soybean, and Medicago revealed that the CaAMT2;1, CaAMT2.4, and CaAMT3;1 have undergone an expansion prior to the divergence of Solanaceae and Leguminosae. The expression of six AMT2 genes was either up-regulated or down-regulated in response to AM colonization. The expression of CaAMT2;1/2;2/2;3 and SlAMT2;1/2;2/2;3 was significantly up-regulated in AM fungi-inoculated roots. A 1,112-bp CaAMT2;1 promoter fragment and a 1,400-bp CaAMT2;2 promoter fragment drove the expression of the ß-glucuronidase gene in the cortex of AM roots. Evaluation of AM colonization under different NH4+ concentrations revealed that a sufficient, but not excessive, supply of NH4+ promotes the growth of chili pepper and the colonization of AM. Furthermore, we demonstrated that CaAMT2;2 overexpression could mediate NH4+ uptake in tomato plants. CONCLUSION: In sum, our results provide new insights into the evolutionary relationships and functional divergence of chili pepper AMT genes. We also identified putative AMT genes expressed in AM symbiotic roots.


Assuntos
Compostos de Amônio , Capsicum , Micorrizas , Micorrizas/metabolismo , Capsicum/genética , Capsicum/metabolismo , Simbiose/fisiologia , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Proteínas de Membrana Transportadoras/genética , Regulação da Expressão Gênica de Plantas
7.
BMC Infect Dis ; 23(1): 459, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430187

RESUMO

BACKGROUND: This study aimed to establish an effective ultrasound diagnostic nomogram for benign or malignant lymph nodes in HIV-infected patients. METHODS: The nomogram is based on a retrospective study of 131 HIV-infected patients who underwent ultrasound assess at the Shanghai Public Health Clinical Center from December 2017 to July 2022. The nomogram's predictive accuracy and discriminative ability were determined by concordance index (C-index) and calibration curve analysis. A nomogram combining the lymph node US characteristics were generated based on the multivariate logistic regression results. RESULTS: Predictors contained in the ultrasound diagnostic nomogram included age (OR 1.044 95%CI: 1.014-1.074 P = 0.004), number of enlarged lymph node regions (OR 5.445 95%CI: 1.139-26.029 P = 0.034), and color Doppler flow imaging (CDFI) grades (OR 9.614 95%CI: 1.889-48.930 P = 0.006). The model displayed good discrimination with a C (ROC) of 0.775 and good calibration. CONCLUSIONS: The proposed nomogram may result in more-accurate diagnostic predictions for benign or malignant lymph nodes in patients with HIV infection.


Assuntos
Infecções por HIV , Humanos , Nomogramas , Estudos Retrospectivos , China , Ultrassonografia , Linfonodos/diagnóstico por imagem
8.
J Sci Food Agric ; 103(12): 5970-5980, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37114712

RESUMO

BACKGROUND: There is currently an increase in the use of new types of fertilizers in modern agriculture. Studies have shown that amino acid fertilizers can improve crop yield and quality. However, their effects on crop rhizosphere ecology and their ecological impacts on crop yield are largely unknown. This study evaluated the effects of a water-soluble amino acid fertilizer (WAAF) on tomatoes and its ecological effects on rhizosphere bacterial communities using greenhouse pot experiments. RESULTS: The results showed that WAAF could promote the growth of tomatoes and improve the quality of fruits more effectively than water-soluble chemical fertilizer controls. Interestingly, WAAF showed a different regulating pattern on root exudates and increased the secretion of 17 major water-soluble root exudates, including hexadecanoic acid and 3-hydroxy-γ-butyrolactone. Water-soluble amino acid fertilizer also affected noticeably the composition, abundance, and beta-diversity of rhizosphere bacterial communities, and strengthened the potential relationships between community members. Water-soluble amino acid fertilizer showed a significant selective enrichment ability and recruited some members of the genera such as Cupriavidus, Ralstonia, Chitinophaga, Gemmatimonas, Mitsuaria, Mucilaginibacter, Paracoccus, Sphingopyxis, and Variovorax. Network analysis and functional prediction implied that, besides fertilizer effects, the recruiting of beneficial microbes involved in chemotaxis and biofilm formation was also a considerable factor in tomato yield and quality improvement. CONCLUSION: Our study revealed ecological and recruiting effects of WAAF on rhizosphere microbes and potentially beneficial microbiota, and provided a basis for the amino acid fertilizer regulation of rhizosphere ecology to improve soil health and further improve crop yield and quality. © 2023 Society of Chemical Industry.


Assuntos
Fertilizantes , Solanum lycopersicum , Solo/química , Solanum lycopersicum/química , Rizosfera , Bacteroidetes , Aminoácidos/química
9.
J Am Chem Soc ; 144(12): 5441-5449, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35274946

RESUMO

A carbene-catalyzed sulfonylation reaction between enone aryl aldehydes and sulfonyl chlorides is disclosed. The reaction effectively installs sulfone moieties in a highly enantioselective manner to afford sulfone-containing bicyclic lactones. The sulfonyl chloride behaves both as an oxidant and a nucleophilic substrate (via its reduced form) in this N-heterocyclic carbene (NHC)-catalyzed process. The NHC catalyst provides both activation and stereoselectivity control on a very remote site of enone aryl aldehyde substrates. Water plays an important role in modulating catalyst deactivation and reactivation routes that involve reactions between NHC and sulfonyl chloride. Experimental studies and DFT calculations suggest that an unprecedented intermediate and a new oxidation mode of the NHC-derived Breslow intermediate are involved in the new asymmetric sulfonylation reaction.


Assuntos
Aldeídos , Sulfonas , Catálise , Metano/análogos & derivados , Estereoisomerismo
10.
Biomed Eng Online ; 20(1): 27, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33743707

RESUMO

BACKGROUND: Lung ultrasound (LUS) can be an important imaging tool for the diagnosis and assessment of lung involvement. Ultrasound sonograms have been confirmed to illustrate damage to a person's lungs, which means that the correct classification and scoring of a patient's sonogram can be used to assess lung involvement. METHODS: The purpose of this study was to establish a lung involvement assessment model based on deep learning. A novel multimodal channel and receptive field attention network combined with ResNeXt (MCRFNet) was proposed to classify sonograms, and the network can automatically fuse shallow features and determine the importance of different channels and respective fields. Finally, sonogram classes were transformed into scores to evaluate lung involvement from the initial diagnosis to rehabilitation. RESULTS AND CONCLUSION: Using multicenter and multimodal ultrasound data from 104 patients, the diagnostic model achieved 94.39% accuracy, 82.28% precision, 76.27% sensitivity, and 96.44% specificity. The lung involvement severity and the trend of COVID-19 pneumonia were evaluated quantitatively.


Assuntos
COVID-19/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pneumonia/diagnóstico por imagem , Ultrassonografia , Algoritmos , Bases de Dados Factuais , Reações Falso-Positivas , Humanos , Processamento de Imagem Assistida por Computador/métodos , Modelos Estatísticos , Redes Neurais de Computação , Linguagens de Programação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Software
11.
Plant Physiol ; 180(1): 465-479, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30760639

RESUMO

Most terrestrial plants form a root symbiosis with arbuscular mycorrhizal (AM) fungi, which receive fixed carbon from the plant and enhance the plant's uptake of mineral nutrients. AM symbiosis improves the phosphorous and nitrogen nutrition of host plants; however, little is known about the role of AM symbiosis in potassium (K+) nutrition. Here, we report that inoculation with the AM fungus Rhizophagus irregularis improved tomato (Solanum lycopersicum) plant growth and K+ acquisition and that K+ deficiency has a negative effect on root growth and AM colonization. Based on its homology to a Lotus japonicus AM-induced K+ transporter, we identified a mycorrhiza-specific tomato K+ transporter, SlHAK10 (Solanum lycopersicum High-affinity Potassium Transporter10), that was exclusively expressed in arbuscule-containing cells. SlHAK10 could restore a yeast K+ uptake-defective mutant in the low-affinity concentration range. Loss of function of SlHAK10 led to a significant decrease in mycorrhizal K+ uptake and AM colonization rate under low-K+ conditions but did not affect arbuscule development. Overexpressing SlHAK10 from the constitutive cauliflower mosaic virus 35S promoter or the AM-specific Solanum melongena Phosphate Transporter4 not only improved plant growth and K+ uptake but also increased AM colonization efficiency and soluble sugar content in roots supplied with low K+ Our results indicate that tomato plants have a SlHAK10-mediated mycorrhizal K+ uptake pathway and that improved plant K+ nutrition could increase carbohydrate accumulation in roots, which facilitates AM fungal colonization.


Assuntos
Glomeromycota/fisiologia , Micorrizas/metabolismo , Proteínas de Plantas/metabolismo , Potássio/farmacocinética , Solanum lycopersicum/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica de Plantas , Lotus/química , Solanum lycopersicum/crescimento & desenvolvimento , Mutação , Micorrizas/fisiologia , Proteínas de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Potássio/metabolismo , Simbiose , Leveduras/genética
12.
Plant Cell Environ ; 43(4): 1069-1083, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31899547

RESUMO

Most land plants can form symbiosis with arbuscular mycorrhizal (AM) fungi to enhance uptake of mineral nutrients, particularly phosphate (Pi) and nitrogen (N), from the soil. It is established that transport of Pi from interfacial apoplast into plant cells depends on the H+ gradient generated by the H+ -ATPase located on the periarbuscular membrane (PAM); however, little evidence regarding the potential link between mycorrhizal N transport and H+ -ATPase activity is available to date. Here, we report that a PAM-localized tomato H+ -ATPase, SlHA8, is indispensable for arbuscule development and mycorrhizal P and N uptake. Knockout of SlHA8 resulted in truncated arbuscule morphology, reduced shoot P and N accumulation, and decreased H+ -ATPase activity and acidification of apoplastic spaces in arbusculated cells. Overexpression of SlHA8 in tomato promoted both P and N uptake, and increased total colonization level, but did not affect arbuscule morphology. Heterogeneous expression of SlHA8 in the rice osha1 mutant could fully complement its defects in arbuscule development and mycorrhizal P and N uptake. Our results propose a pivotal role of the SlHA8 in energizing both the symbiotic P and N transport, and highlight the evolutionary conservation of the AM-specific H+ -ATPase orthologs in maintaining AM symbiosis across different mycorrhizal plant species.


Assuntos
Hifas/genética , Micorrizas/enzimologia , Nitrogênio/metabolismo , Fosfatos/metabolismo , Proteínas de Plantas/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Simbiose , Membrana Celular/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/microbiologia , Solanum lycopersicum/fisiologia , Micorrizas/metabolismo , Micorrizas/fisiologia , Oryza/metabolismo , Oryza/microbiologia , Oryza/fisiologia , Proteínas de Plantas/fisiologia , ATPases Translocadoras de Prótons/fisiologia
13.
Int J Mol Sci ; 18(8)2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28757561

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) causes severe losses in the global pig industry. In the present study, we investigated the molecular characterization of porcine interferon stimulated gene 12a (ISG12A) and confirmed its anti-PRRSV ability for the first time. We found that porcine ISG12A was localized in mitochondria and significantly decreased the number of cells in G2/S phase. Porcine ISG12A mRNA was up-regulated in cells/tissues of Tongcheng (TC) pigs and Large White (LW) pigs after PRRSV challenge. More importantly, the ectopic overexpression of ISG12A could significantly suppress PRRSV replication at 24, 36 and 48 h post challenge (hpc), which was confirmed by detecting PRRSV ORF7 mRNA with quantitative reverse transcription polymerase chain reaction (qRT-PCR) and PRRSV N protein with indirect immunofluorescence assay (IFA) in MARC-145 cells. Meanwhile, knockdown of endogenic ISG12A could obviously facilitate PRRSV replication in MARC-145 cells at 36 hpc. The results will lead to a better understanding of the interaction between host immune system and PRRSV, which may help us develop novel therapeutic tools to control PRRSV.


Assuntos
Proteínas de Membrana/genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Animais , Linhagem Celular , Chlorocebus aethiops , Proteínas de Membrana/metabolismo , Proteínas de Membrana/farmacologia , Mitocôndrias/metabolismo , Síndrome Respiratória e Reprodutiva Suína/genética , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Vírus da Síndrome Respiratória e Reprodutiva Suína/efeitos dos fármacos , Suínos , Regulação para Cima , Replicação Viral/efeitos dos fármacos
14.
Mycorrhiza ; 26(7): 645-56, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27103309

RESUMO

In plants, the plasma membrane H(+)-ATPase (HA) is considered to play a crucial role in regulating plant growth and respoding to environment stresses. Multiple paralogous genes encoding different isozymes of HA have been identified and characterized in several model plants, while limited information of the HA gene family is available to date for tomato. Here, we describe the molecular and expression features of eight HA-encoding genes (SlHA1-8) from tomato. All these genes are interrupted by multiple introns with conserved positions. SlHA1, 2, and 4 were widely expressed in all tissues, while SlHA5, 6, and 7 were almost only expressed in flowers. SlHA8, the transcripts of which were barely detectable under normal or nutrient-/salt-stress growth conditions, was strongly activated in arbuscular mycorrhizal (AM) fungal-colonized roots. Extreme lack of SlHA8 expression in M161, a mutant defective to AM fungal colonization, provided genetic evidence towards the dependence of its expression on AM symbiosis. A 1521-bp SlHA8 promoter could direct the GUS reporter expression specifically in colonized cells of transgenic tobacco, soybean, and rice mycorrhizal roots. Promoter deletion assay revealed a 223-bp promoter fragment of SlHA8 containing a variant of AM-specific cis-element MYCS (vMYCS) sufficient to confer the AM-induced activity. Targeted deletion of this motif in the corresponding promoter region causes complete abolishment of GUS staining in mycorrhizal roots. Together, these results lend cogent evidence towards the evolutionary conservation of a potential regulatory mechanism mediating the activation of AM-responsive HA genes in diverse mycorrhizal plant species.


Assuntos
Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Micorrizas/fisiologia , Proteínas de Plantas/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Solanum lycopersicum/enzimologia , Membrana Celular/enzimologia , Genoma de Planta , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , ATPases Translocadoras de Prótons/genética , Especificidade da Espécie , Simbiose , Transcriptoma
15.
Plant Cell Physiol ; 56(4): 674-87, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25535196

RESUMO

In plants, the GH3 gene family is widely considered to be involved in a broad range of plant physiological processes, through modulation of hormonal homeostasis. Multiple GH3 genes have been functionally characterized in several plant species; however, to date, limited works to study the GH3 genes in tomato have been reported. Here, we characterize the expression and regulatory profiles of six tomato GH3 genes, SlGH3.2, SlGH3.3, SlGH3.4, SlGH3.7, SlGH3.9 and SlGH3.15, in response to different phytohormone applications and arbuscular mycorrhizal (AM) fungal colonization. All six GH3 genes showed inducible responses to external IAA, and three members were significantly up-regulated in response to AM symbiosis. In particular, SlGH3.4, the transcripts of which were barely detectable under normal growth conditions, was strongly activated in the IAA-treated and AM fungal-colonized roots. A comparison of the SlGH3.4 expression in wild-type plants and M161, a mutant with a defect in AM symbiosis, confirmed that SlGH3.4 expression is highly correlated to mycorrhizal colonization. Histochemical staining demonstrated that a 2,258 bp SlGH3.4 promoter fragment could drive ß-glucuronidase (GUS) expression strongly in root tips, steles and cortical cells of IAA-treated roots, but predominantly in the fungal-colonized cells of mycorrhizal roots. A truncated 654 bp promoter failed to direct GUS expression in IAA-treated roots, but maintained the symbiosis-induced activity in mycorrhizal roots. In summary, our results suggest that a mycorrhizal signaling pathway that is at least partially independent of the auxin signaling pathway has evolved for the co-regulation of the auxin- and mycorrhiza-activated GH3 genes in plants.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Ácidos Indolacéticos/farmacologia , Micorrizas/fisiologia , Proteínas de Plantas/metabolismo , Solanum lycopersicum/genética , Simbiose/efeitos dos fármacos , Cromossomos de Plantas/genética , Glucuronidase/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Mutação/genética , Micorrizas/efeitos dos fármacos , Filogenia , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase em Tempo Real , Simbiose/genética , Fatores de Tempo
16.
Org Lett ; 26(20): 4394-4399, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38742796

RESUMO

A carbene-catalyzed enantioselective addition of sulfinate to ketones between 2-benzoylbenzaldehyde and sulfonyl chloride is disclosed. Up to now, the carbon and heteroatom nucleophiles have effectively undergone catalytic enantioselective addition to carbonyl molecules to introduce functionalities and chirality. Sulfone, as an important class of sulfur-containing functional groups, represents highly valuable motifs in medicines and natural products. It remains undeveloped for the catalytic asymmetric addition of sulfinate to carbonyls. Herein we disclosed the first catalytic enantioselective addition of sulfinate to ketones for the synthesis of sulfones via N-heterocyclic carbene (NHC) catalysis. The sulfonyl chloride behaves both as an oxidant and as a nucleophilic substrate in this carbene-catalyzed process. Experimental studies suggested that the Breslow intermediate can be SET oxidized by sulfonyl chloride to generate the sulfonyl radical. This novel synthetic approach for the asymmetric addition of sulfinate to carbonyls can also be used to modify the commercially available functional molecules.

17.
Front Neurol ; 15: 1348011, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638313

RESUMO

Introduction: The relationship between oxidative balance score (OBS), an emerging integrative metric for assessing individual redox homeostasis, and the prevalence of stroke in the general population remains unknown. We aimed to explore these relationships in the National Health and Nutrition Examination Survey (NHANES). We investigated the relationship between the oxidative balance score (OBS) and stroke prevalence using NHANES data from 1999-2018. Methods: We included eligible individuals from NHANES 1999-2018. OBS calculations were based on previously validated methods, and stroke diagnoses were based on self-reports in questionnaires. Multivariable logistic regression analyses were used to examine the independent associations of overall, dietary, and lifestyle OBS with stroke prevalence. In addition, restricted cubic spline (RCS), stratified analysis, and sensitivity analysis were used. Results: We included 25,258 participants aged 20-85 years, in which the prevalence of stroke was 2.66%. After adjusting for all confounders, overall and dietary OBS, but not lifestyle OBS, were inversely associated with the prevalence of stroke [odds ratios and 95% confidence intervals of 0.97 (0.96, 0.99) and 0.98 (0.96, 0.99) for overall and dietary OBS, respectively, both p < 0.05]. In addition, there was a dose-response relationship between overall and dietary OBS and stroke prevalence. The RCS showed that these relationships were linear. Stratified analyses indicated that socioeconomic status (SES) significantly influenced the relationship between all OBS and stroke prevalence. Conclusion: Dietary OBS, but not lifestyle OBS, had an inverse relationship with the prevalence of stroke in the general population. SES significantly influenced the protective effect of OBS against stroke. These findings emphasize the importance of integrated antioxidant properties from diet for stroke prevention.

18.
Front Oncol ; 14: 1345190, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38571508

RESUMO

Introduction: Tumor treating fields (TTFields) have earned substantial attention in recent years as a novel therapeutic approach with the potential to improve the prognosis of glioblastoma (GBM) patients. However, the impact of TTFields remains a subject of ongoing debate. This study aimed to offer real-world evidence on TTFields therapy for GBM, and to investigate the clinical determinants affecting its efficacy. Methods: We have reported a retrospective analysis of 81 newly diagnosed Chinese GBM patients who received TTFields/Stupp treatment in the Second Affiliated Hospital of Zhejiang University. Overall survival (OS) and progression-free survival (PFS) were analyzed using Kaplan-Meier method. Cox regression models with time-dependent covariates were utilized to address non-proportional hazards and to assess the influence of clinical variables on PFS and OS. Results: The median PFS and OS following TTFields/STUPP treatment was 12.6 months (95% CI 11.0-14.1) and 21.3 months (95% CI 10.0-32.6) respectively. Long-term TTFields treatment (>2 months) exhibits significant improvements in PFS and OS compared to the short-term treatment group (≤2 months). Time-dependent covariate COX analysis revealed that longer TTFields treatment was correlated with enhanced PFS and OS for up to 12 and 13 months, respectively. Higher compliance to TTFields (≥ 0.8) significantly reduced the death risk (HR=0.297, 95%CI 0.108-0.819). Complete surgical resection and MGMT promoter methylation were associated with significantly lower risk of progression (HR=0.337, 95% CI 0.176-0.643; HR=0.156, 95% CI 0.065-0.378) and death (HR=0.276, 95% CI 0.105-0.727; HR=0.249, 95% CI 0.087-0.710). Conclusion: The TTFields/Stupp treatment may prolong median OS and PFS in GBM patients, with long-term TTFields treatment, higher TTFields compliance, complete surgical resection, and MGMT promoter methylation significantly improving prognosis.

19.
Clin Hemorheol Microcirc ; 84(2): 205-214, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37125544

RESUMO

OBJECTIVES: To establish the prediction model of liver fibrosis by combining ultrasound elastography and platelet count and evaluates its clinical value. METHODS: 146 patients with chronic liver diseases(CLD) admitted to our hospital from July 2020 to July 2022 were collected for liver biopsy pathological examination, and the results of ultrasound elastography (liver hardness value) and serological indicators were collected. Based on the results of Spearman correlation test and multiple linear regression model, the prediction model of liver fibrosis using ultrasound elastography combined with platelet count was constructed and verified. RESULTS: The AUC of transient elastography combined with platelet count model (FSP) in the diagnosis of S2, S3 and S4 phases of liver fibrosis was 0.665, 0.835 and 0.909, with specificity of 81.5%, 90.0% and 100%. The AUC of sound touch elastography combined with platelet count model (STEP) in diagnosing S2, S3 and S4 phases of liver fibrosis was 0.685, 0.810 and 0884, with specificity of 96.3%, 90.0% and 83.3%, which are higher than APRI, FIB-4, FORNS, AAR and other models. CONCLUSION: Ultrasound elastography combined with platelet count model has good diagnostic efficacy for liver fibrosis.


Assuntos
Técnicas de Imagem por Elasticidade , Humanos , Técnicas de Imagem por Elasticidade/métodos , Contagem de Plaquetas , Aspartato Aminotransferases , Cirrose Hepática/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Biópsia , Biomarcadores
20.
Carbohydr Polym ; 307: 120611, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36781273

RESUMO

BDDE substituted HA hydrogels remain the most commonly used HA product in the biomedical field. The physical and biochemical properties of the hydrogels are dependent on the degree of modification and substitution patterns/positions, thus, characterizing their fine structure is of great importance for quality assurance. In this study, we developed novel LC-MS methods for accurate determination of MoD as well as in-depth characterization of the linkage network. Fragments resulted from enzymatic depolymerization were resolved by a porous graphitic carbon column followed by online tandem-MS for determining the modification site/residue. With high-resolution separation, two types of previously unknown structures were detected in the cross-linked fragments of 2-B-2 and 4-B-2. Based on the feature of resistance to NaBH4 reduction, these structures contain a GlcNAc residue modified at OH1. This special sugar unit likely derived from reducing end of the native polysaccharide could be a signature to discriminate subtle batch to batch variations.

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