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1.
Plant J ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39139125

RESUMEN

Soil salinity significantly limits rice productivity, but it is poorly understood how excess sodium (Na+) is delivered to the grains at the reproductive stage. Here, we functionally characterized OsHAK4, a member of the clade IV HAK/KUP/KT transporter subfamily in rice. OsHAK4 was localized to the plasma membrane and exhibited influx transport activity for Na+, but not for K+. Analysis of organ- and growth stage-dependent expression patterns showed that very low expression levels of OsHAK4 were detected at the vegetative growth stage, but its high expression in uppermost node I, peduncle, and rachis was found at the reproductive stage. Immunostaining indicated OsHAK4 localization in the phloem region of node I, peduncle, and rachis. Knockout of OsHAK4 did not affect the growth and Na+ accumulation at the vegetative stage. However, at the reproductive stage, the hak4 mutants accumulated higher Na+ in the peduncle, rachis, husk, and brown rice compared to the wild-type rice. Element imaging revealed higher Na+ accumulation at the phloem region of the peduncle in the mutants. These results indicate that OsHAK4 plays a crucial role in retrieving Na+ from the phloem in the upper nodes, peduncle, and rachis, thereby preventing Na+ distribution to the grains at the reproductive stage of rice.

2.
Shanghai Kou Qiang Yi Xue ; 33(2): 200-204, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-39005100

RESUMEN

PURPOSE: To analyse the types of chairside CAD/CAM all-ceramic restorations and the color range of all-ceramic materials used so as to provide reference for the application of clinical chairside all-ceramic restoration and the color selection of all-ceramic materials. METHODS: IPS e.max CAD prostheses and related data were collected from January 2021 to December 2021 from the Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine. The number and type of restorations and the color of materials were investigated and analyzed by descriptive statistics. RESULTS: A total of 1 374 restorations were included, of which 624 were crown restorations, accounting for 45.41% of the total restorations. 516 cases were veneer, accounting for 37.55%; 219 were inlays, accounting for 15.94%; fixed bridges were all adhesive bridges, with the least number with only 15 cases, accounting for 1.09%. In terms of the selection of restoration materials, the use rate of low-transparent(LT) ceramic blocks was significantly higher than that of other transparent ceramic blocks. A was the most frequently used ceramic color. The most frequently used porcelain blocks for veneers were LTA2 and LTA1; for inlay were LTA3; for crowns were LTA2 and LTA3. The blocks used in the fixed bridges were all LT, and A3 color was the majority. CONCLUSIONS: Chairside CAD/CAM all-ceramic prostheses made of IPS e.max CAD materials have been widely used in clinical practice. The types of prostheses include veneer, inset, crown and fixed bridge. The most commonly used IPS e.max CAD blocks are LTA2, LTA3 and LTA1. These findings have certain guiding significance for the clinical restoration decision and the reserve of porcelain blocks in primary hospitals.


Asunto(s)
Cerámica , Diseño Asistido por Computadora , Coronas , Cerámica/química , Diseño de Prótesis Dental/métodos , Porcelana Dental/química , Color , Humanos , Coronas con Frente Estético , Incrustaciones/métodos , Restauración Dental Permanente/métodos
3.
BMC Genomics ; 25(1): 525, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807041

RESUMEN

BACKGROUND: The Rh blood group system is characterized by its complexity and polymorphism, encompassing 56 different antigens. Accurately predicting the presence of the C antigen using genotyping methods has been challenging. The objective of this study was to evaluate the accuracy of various genotyping methods for predicting the Rh C and to identify a suitable method for the Chinese Han population. METHODS: In total, 317 donors, consisting 223 D+ (including 20 with the Del phenotype) and 94 D- were randomly selected. For RHC genotyping, 48C and 109bp insertion were detected on the Real-time PCR platform and -292 substitution was analyzed via restriction fragment length polymorphism (RFLP). Moreover, the promoter region of the RHCE gene was sequenced to search for other nucleotide substitutions between RHC and RHc. Agreement between prediction methods was evaluated using the Kappa statistic, and comparisons between methods were conducted via the χ2 test. RESULTS: The analysis revealed that the 48C allele, 109bp insertion, a specific pattern observed in RFLP results, and wild-type alleles of seven single nucleotide polymorphisms (SNPs) were in strong agreement with the Rh C, with Kappa coefficients exceeding 0.8. However, there were instances of false positives or false negatives (0.6% false negative rate for 109bp insertion and 5.4-8.2% false positive rates for other methods). The 109bp insertion method exhibited the highest accuracy in predicting the Rh C, at 99.4%, compared to other methods (P values≤0.001). Although no statistical differences were found among other methods for predicting Rh C (P values>0.05), the accuracies in descending order were 48C (94.6%) > rs586178 (92.7%) > rs4649082, rs2375313, rs2281179, rs2072933, rs2072932, and RFLP (92.4%) > rs2072931 (91.8%). CONCLUSIONS: None of the methods examined can independently and accurately predict the Rh C. However, the 109bp insertion test demonstrated the highest accuracy for predicting the Rh C in the Chinese Han population. Utilizing the 109bp insertion test in combination with other methods may enhance the accuracy of Rh C prediction.


Asunto(s)
Pueblo Asiatico , Técnicas de Genotipaje , Polimorfismo de Nucleótido Simple , Sistema del Grupo Sanguíneo Rh-Hr , Humanos , Sistema del Grupo Sanguíneo Rh-Hr/genética , Pueblo Asiatico/genética , Técnicas de Genotipaje/métodos , China , Genotipo , Alelos , Polimorfismo de Longitud del Fragmento de Restricción , Frecuencia de los Genes , Regiones Promotoras Genéticas , Pueblos del Este de Asia
4.
Blood Adv ; 8(13): 3388-3401, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38701351

RESUMEN

ABSTRACT: Glycoprotein Ibα (GPIbα), the ligand-binding subunit of platelet GPIb-IX complex, interacts with von Willebrand factor (VWF) exposed at the injured vessel wall, initiating platelet adhesion, activation, hemostasis, and thrombus formation. The cytoplasmic tail of GPIbα interacts with 14-3-3ζ, regulating the VWF-GPIbα-elicited signal transduction and VWF binding function of GPIbα. However, we unexpectedly found that the GPIbα-14-3-3ζ association, beyond VWF-dependent function, is essential for general platelet activation. We found that the myristoylated peptide of GPIbα C-terminus MPαC, a potential GPIbα inhibitor, by itself induced platelet aggregation, integrin αIIbß3 activation, granule secretion, and phosphatidylserine (PS) exposure. Conversely, the deletion of the cytoplasmic tail of GPIbα in mouse platelets (10aa-/-) decreased platelet aggregation, integrin αIIbß3 activation, granule secretion, and PS exposure induced by various physiological agonists. Phosphoproteome-based kinase activity profiling revealed significantly upregulated protein kinase C (PKC) activity in MPαC-treated platelets. MPαC-induced platelet activation was abolished by the pan-PKC inhibitor and PKCα deletion. Decreased PKC activity was observed in both resting and agonist-stimulated 10aa-/- platelets. GPIbα regulates PKCα activity by sequestering 14-3-3ζ from PKCα. In vivo, the deletion of the GPIbα cytoplasmic tail impaired mouse hemostasis and thrombus formation and protected against platelet-dependent pulmonary thromboembolism. Therefore, our findings demonstrate an essential role for the GPIbα cytoplasmic tail in regulating platelet general activation and thrombus formation beyond the VWF-GPIbα axis.


Asunto(s)
Plaquetas , Activación Plaquetaria , Complejo GPIb-IX de Glicoproteína Plaquetaria , Complejo GPIb-IX de Glicoproteína Plaquetaria/metabolismo , Animales , Ratones , Humanos , Plaquetas/metabolismo , Proteínas 14-3-3/metabolismo , Factor de von Willebrand/metabolismo , Trombosis/metabolismo , Transducción de Señal , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Ratones Noqueados , Agregación Plaquetaria
7.
Front Mol Neurosci ; 17: 1355140, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38550251

RESUMEN

Introduction: Cumulative evidence suggests that sensory cortices interact with the basolateral amygdala (BLA) defense circuitry to mediate threat conditioning, memory retrieval, and extinction learning. The olfactory piriform cortex (PC) has been posited as a critical site for olfactory associative memory. Recently, we have shown that N-methyl-D-aspartate receptor (NMDAR)-dependent plasticity in the PC critically underpins olfactory threat extinction. Aging-associated impairment of olfactory threat extinction is related to the hypofunction of NMDARs in the PC. Methods: In this study, we investigated activation of neuronal cFos and epigenetic marks in the BLA and PC using immunohistochemistry, following olfactory threat conditioning and extinction learning in rats. Results: We found highly correlated cFos activation between the posterior PC (pPC) and BLA. cFos was correlated with the degree of behavioral freezing in the pPC in both adult and aged rats, and in the BLA only in adult rats. Markers of DNA methylation 5 mC and histone acetylation H3K9/K14ac, H3K27ac, and H4ac exhibited distinct training-, region-, and age-dependent patterns of activation. Strong correlations of epigenetic marks between the BLA and pPC in adult rats were found to be a general feature. Conversely, aged rats only exhibited correlations of H3 acetylations between the two structures. Histone acetylation varied as a function of aging, revealed by a reduction of H3K9/K14ac and an increase of H4ac in aged brains at basal condition and following threat conditioning. Discussion: These findings underscore the coordinated role of PC and BLA in olfactory associative memory storage and extinction, with implications for understanding aging related cognitive decline.

8.
J Environ Manage ; 355: 120481, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38447515

RESUMEN

Significant amounts of the greenhouse gas methane (CH4) are released into the atmosphere worldwide via freshwater sources. The surface methane maximum (SMM), where methane is supersaturated in surface water, has been observed in aquatic systems and contributes significantly to emissions. However, little is known about the temporal and spatial variability of SMM or the mechanisms underlying its development in artificial reservoirs. Here, the community composition of methanogens as major methane producers in the water column and the mcrA gene was investigated, and the cause of surface methane supersaturation was analyzed. In accordance with the findings, elevated methane concentration of SMM in the transition zone, with an annually methane emission flux 2.47 times higher than the reservoir average on a large and deep reservoir. In the transition zone, methanogens with mcrA gene abundances ranging from 0.5 × 103-1.45 × 104 copies/L were found. Methanobacterium, Methanoseata and Methanosarcina were the three dominate methanogens, using both acetic acid and H2/CO2 pathways. In summary, this study contributes to our comprehension of CH4 fluxes and their role in the atmospheric methane budget. Moreover, it offers biological proof of methane generation, which could aid in understanding the role of microbial methanogenesis in aerobic water.


Asunto(s)
Gases de Efecto Invernadero , Agua , Metano/análisis , Agua Dulce , Atmósfera
10.
Angew Chem Int Ed Engl ; 63(16): e202318040, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38349957

RESUMEN

We report a highly enantioselective intermolecular C-H bond silylation catalyzed by a phosphoramidite-ligated iridium catalyst. Under reagent-controlled protocols, propargylsilanes resulting from C(sp3)-H functionalization, as well the regioisomeric and synthetically versatile allenylsilanes, could be obtained with excellent levels of enantioselectivity and good to excellent control of propargyl/allenyl selectivity. In the case of unsymmetrical dialkyl acetylenes, good to excellent selectivity for functionalization at the less-hindered site was also observed. A variety of electrophilic silyl sources (R3SiOTf and R3SiNTf2), either commercial or in situ-generated, were used as the silylation reagents, and a broad range of simple and functionalized alkynes, including aryl alkyl acetylenes, dialkyl acetylenes, 1,3-enynes, and drug derivatives were successfully employed as substrates. Detailed mechanistic experiments and DFT calculations suggest that an η3-propargyl/allenyl Ir intermediate is generated upon π-complexation-assisted deprotonation and undergoes outer-sphere attack by the electrophilic silylating reagent to give propargylic silanes, with the latter step identified as the enantiodetermining step.

11.
Vox Sang ; 119(4): 383-387, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38245843

RESUMEN

BACKGROUND AND OBJECTIVES: B(A) phenotype is usually formed by nucleotide mutations in the ABO*B.01 allele, with their products exhibiting glycosyltransferases (GTs) A and B overlapping functionality. We herein report a B(A) allele found in a Chinese family. MATERIALS AND METHODS: The entire ABO genes of the probands, including flanking regulatory regions, were sequenced through PacBio third-generation long-read single-molecule real-time sequencing. 3D molecular models of the wild-type and mutant GTB were generated using the DynaMut web server. The effect of the mutation on the enzyme function was predicted by PROVEAN and PolyPhen2. The predictions of stability changes were performed using DynaMut and SNPeffect. RESULTS: Based on serological and sequencing features, we concluded the two probands as possible cases of the B(A) phenotype. Crystallization analysis showed that Thr266 substitution does not disrupt the hydrogen bonds. However, some changes in interatomic contacts, such as loss of ionic interactions and hydrophobic contacts, and addition of weak hydrogen bonds, may have affected protein stability to some extent. This mutation was predicted to have a benign effect on enzyme function and slightly reduce protein stability. CONCLUSION: The probands had the same novel B(A) allele with a c.797T>C (p.Met266Thr) mutation on the ABO*B.01 backbone.


Asunto(s)
Glicosiltransferasas , Mutación Missense , Humanos , Fenotipo , Mutación , Glicosiltransferasas/química , Glicosiltransferasas/genética , Alelos , China , Sistema del Grupo Sanguíneo ABO/genética , Genotipo
12.
J Phys Condens Matter ; 36(16)2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38198736

RESUMEN

This study utilizes both experimental and computational approaches to investigate the performance of Lu2Ti2O7(LTO) and Lu1.5Ce0.5Ti2O7+x(LCTO) pyrochlores under high pressure. The structural changes of LTO and LCTO pyrochlores were characterized usingin-situsynchrotron x-ray diffraction (SXRD) andin-situRaman spectroscopy at pressures up to 44.6 GPa. The kinks inP-aandP-Vcurves at around 5 GPa are mainly attributed to the interaction between the pressure medium and the isostructural changes. The onset pressures for transitioning from the cubic pyrochlore phase (Fd-3 m) to the monoclinic phase (P21) are observed at 32.5 GPa and 38.1 GPa, respectively. It is important to note that at the highest measured pressures, the phase transition remains incomplete. This partial transition is likely the result of oriented disorder among cations and anions under high pressure. In addition, introducing Ce as a dopant significantly enhances structural stability. This can be explained by the larger ionic radius of Ce, which hinders the disordering process.

13.
Blood Cells Mol Dis ; 104: 102798, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37813040

RESUMEN

Thrombocytopenia is a critical complication after radiation therapy and exposure. Dysfunction of megakaryocyte development and platelet production are key pathophysiological stages in ionizing radiation (IR)-induced thrombocytopenia. Protein kinase C (PKC) plays an important role in regulating megakaryocyte development and platelet production. However, it remains unclear how PKC regulates IR-induced megakaryocyte apoptosis. In this study, we found that pretreatment of PKC pan-inhibitor Go6983 delayed IR-induced megakaryocyte apoptosis, and inhibited IR-induced mitochondrial membrane potential and ROS production in CMK cells. Moreover, suppressing PKC activation inhibited cleaved caspase3 expression and reduced p38 phosphorylation levels, and IR-induced PKC activation might be regulated by p53. In vivo experiments confirmed that Go6983 promoted platelet count recovery after 21 days of 3 Gy total body irradiation. Furthermore, Go6983 reduced megakaryocyte apoptosis, increased the number of megakaryocyte and polyploid formation in bone marrow, and improved the survival rate of 6 Gy total body irradiation. In conclusion, our results provided a potential therapeutic target for IR-induced thrombocytopenia.


Asunto(s)
Megacariocitos , Trombocitopenia , Humanos , Proteína Quinasa C/metabolismo , Proteína Quinasa C/uso terapéutico , Rayos X , Trombocitopenia/etiología , Trombopoyesis , Apoptosis , Plaquetas
14.
Clinics ; 72(1): 1-4, Jan. 2017. tab
Artículo en Inglés | LILACS | ID: biblio-840038

RESUMEN

OBJECTIVE: To compare the advantages and disadvantages of emergency percutaneous coronary intervention through the left radial artery with those of emergency percutaneous coronary intervention through the femoral artery. METHODS: A total of 206 patients with acute myocardial infarction who required emergency percutaneous coronary intervention and were admitted to our hospital between January 2011 and August 2013 were divided into the following two groups: a group that underwent percutaneous coronary intervention through the left radial artery and a group that underwent percutaneous coronary intervention through the femoral artery. The times required for angiographic catheter and guiding catheter placement, the success rate of the procedure and the incidence of vascular complications in the two groups were observed. RESULTS: There was no significant difference in catheter placement time or the ultimate success rate of the procedure between the two groups. However, the left radial artery group showed a significantly lower incidence of vascular complications than the femoral artery group (p<0.05). CONCLUSION: Emergency percutaneous coronary intervention through the left radial artery is associated with less vascular complications than emergency percutaneous coronary intervention through the femoral artery and is thus potentially advantageous for patients.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Tratamiento de Urgencia , Arteria Femoral , Infarto del Miocardio/cirugía , Intervención Coronaria Percutánea/métodos , Arteria Radial , Intervención Coronaria Percutánea/efectos adversos , Estudios Prospectivos , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
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