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1.
Nature ; 624(7991): 282-288, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38092911

RESUMEN

Miniaturized lasers play a central role in the infrastructure of modern information society. The breakthrough in laser miniaturization beyond the wavelength scale has opened up new opportunities for a wide range of applications1-4, as well as for investigating light-matter interactions in extreme-optical-field localization and lasing-mode engineering5-19. An ultimate objective of microscale laser research is to develop reconfigurable coherent nanolaser arrays that can simultaneously enhance information capacity and functionality. However, the absence of a suitable physical mechanism for reconfiguring nanolaser cavities hinders the demonstration of nanolasers in either a single cavity or a fixed array. Here we propose and demonstrate moiré nanolaser arrays based on optical flatbands in twisted photonic graphene lattices, in which coherent nanolasing is realized from a single nanocavity to reconfigurable arrays of nanocavities. We observe synchronized nanolaser arrays exhibiting high spatial and spectral coherence, across a range of distinct patterns, including P, K and U shapes and the Chinese characters '' and '' ('China' in Chinese). Moreover, we obtain nanolaser arrays that emit with spatially varying relative phases, allowing us to manipulate emission directions. Our work lays the foundation for the development of reconfigurable active devices that have potential applications in communication, LiDAR (light detection and ranging), optical computing and imaging.

2.
Plant Physiol ; 194(3): 1545-1562, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38039100

RESUMEN

Brassinosteroids (BRs) are a group of steroid hormones that play crucial roles in plant growth and development. Atypical bHLH transcription factors that lack the basic region for DNA binding have been implicated in BR signaling. However, the underlying mechanisms of atypical bHLHs in regulation of rice (Oryza sativa) BR signaling are still largely unknown. Here, we describe a systematic characterization of INCREASED LEAF INCLINATION (ILI) subfamily atypical bHLH transcription factors in rice. A total of 8 members, ILI1 to ILI8, with substantial sequence similarity were retrieved. Knockout and overexpression analyses demonstrated that these ILIs play unequally redundant and indispensable roles in BR-mediated growth and development in rice, with a more prominent role for ILI4 and ILI5. The ili3/4/5/8 quadruple and ili1/3/4/7/8 quintuple mutants displayed tremendous BR-related defects with severe dwarfism, erect leaves, and sterility. Biochemical analysis showed that ILIs interact with OsbHLH157 and OsbHLH158, which are also atypical bHLHs and have no obvious transcriptional activity. Overexpression of OsbHLH157 and OsbHLH158 led to drastic BR-defective growth, whereas the osbhlh157 osbhlh158 double mutant developed a typical BR-enhanced phenotype, indicating that OsbHLH157 and OsbHLH158 play a major negative role in rice BR signaling. Further transcriptome analyses revealed opposite effects of ILIs and OsbHLH157/OsbHLH158 in regulation of downstream gene expression, supporting the antagonism of ILIs and OsbHLH157/OsbHLH158 in maintaining the balance of BR signaling. Our results provide insights into the mechanism of BR signaling and plant architecture formation in rice.


Asunto(s)
Oryza , Oryza/genética , Brasinoesteroides , Transducción de Señal , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Perfilación de la Expresión Génica
3.
J Biol Chem ; 299(1): 102765, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36470423

RESUMEN

Hyperlipidemia characterized by high blood levels of free fatty acids (FFAs) is important for the progression of inflammatory cardiovascular diseases. Integrin ß1 is a transmembrane receptor that drives various cellular functions, including differentiation, migration, and phagocytosis. However, the underlying mechanisms modifying integrin ß1 protein and activity in mediating monocyte/macrophage adhesion to endothelium remain poorly understood. In this study, we demonstrated that integrin ß1 protein underwent S-nitrosylation in response to nitrosative stress in macrophages. To examine the effect of elevated levels of FFA on the modulation of integrin ß1 expression, we treated the macrophages with a combination of oleic acid and palmitic acid (2:1) and found that FFA activated inducible nitric oxide synthase/nitric oxide and increased the integrin ß1 protein level without altering the mRNA level. FFA promoted integrin ß1 S-nitrosylation via inducible nitric oxide synthase/nitric oxide and prevented its degradation by decreasing binding to E3 ubiquitin ligase c-Cbl. Furthermore, we found that increased integrin α4ß1 heterodimerization resulted in monocyte/macrophage adhesion to endothelium. In conclusion, these results provided novel evidence that FFA-stimulated N--O stabilizes integrin ß1via S-nitrosylation, favoring integrin α4ß1 ligation to promote vascular inflammation.


Asunto(s)
Células Endoteliales , Ácidos Grasos no Esterificados , Monocitos , Ácidos Grasos no Esterificados/metabolismo , Integrina alfa4beta1/metabolismo , Monocitos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Integrina beta1/metabolismo , Estabilidad Proteica , Células Endoteliales/metabolismo , Unión Proteica , Estrés Fisiológico
4.
Magn Reson Med ; 92(3): 1115-1127, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38730562

RESUMEN

PURPOSE: T1 mapping is a widely used quantitative MRI technique, but its tissue-specific values remain inconsistent across protocols, sites, and vendors. The ISMRM Reproducible Research and Quantitative MR study groups jointly launched a challenge to assess the reproducibility of a well-established inversion-recovery T1 mapping technique, using acquisition details from a seminal T1 mapping paper on a standardized phantom and in human brains. METHODS: The challenge used the acquisition protocol from Barral et al. (2010). Researchers collected T1 mapping data on the ISMRM/NIST phantom and/or in human brains. Data submission, pipeline development, and analysis were conducted using open-source platforms. Intersubmission and intrasubmission comparisons were performed. RESULTS: Eighteen submissions (39 phantom and 56 human datasets) on scanners by three MRI vendors were collected at 3 T (except one, at 0.35 T). The mean coefficient of variation was 6.1% for intersubmission phantom measurements, and 2.9% for intrasubmission measurements. For humans, the intersubmission/intrasubmission coefficient of variation was 5.9/3.2% in the genu and 16/6.9% in the cortex. An interactive dashboard for data visualization was also developed: https://rrsg2020.dashboards.neurolibre.org. CONCLUSION: The T1 intersubmission variability was twice as high as the intrasubmission variability in both phantoms and human brains, indicating that the acquisition details in the original paper were insufficient to reproduce a quantitative MRI protocol. This study reports the inherent uncertainty in T1 measures across independent research groups, bringing us one step closer to a practical clinical baseline of T1 variations in vivo.


Asunto(s)
Encéfalo , Colaboración de las Masas , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Fantasmas de Imagen , Humanos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Reproducibilidad de los Resultados , Procesamiento de Imagen Asistido por Computador/métodos , Mapeo Encefálico/métodos , Masculino , Femenino , Adulto , Algoritmos
5.
FASEB J ; 37(1): e22673, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36468692

RESUMEN

Calcium modulates bone cell recruitment, differentiation, and function by binding to the calcium-sensing receptor (CaSR). However, the function of CaSR induced by high extracellular calcium (Ca2+ e ) in the regulation of osteoclast formation in rheumatoid arthritis (RA) remains unknown. Here, we used TNFα-transgenic (TNFTG ) RA mice and their wildtype (WT) littermates fed a normal or a rescue diet (high calcium, high phosphorus, and high lactose diet, termed rescue diet) to compare their joint bone phenotypes. In comparison to TNFTG mice fed the normal diet, articular bone volume and cartilage area are increased, whereas inflamed area, eroded surface, TRAP+ surface, and osteoclast-related genes expression are decreased in TNFTG mice fed the rescue diet. Besides, TNFTG mice fed the rescue diet were found to exhibit more CaSR+ area and less NFATc1+ /TRAP+ area. Furthermore, at normal Ca2+ e concentrations, osteoclast precursors (OCPs) from TNFTG mice formed more osteoclasts than OCPs from WT mice, but the number of osteoclasts gradually decreased when the Ca2+ e concentration increased. Meanwhile, the expression of CaSR increased responding to a high level of Ca2+ e , whereas the expression of NF-κB/NFATc1 signaling molecules decreased. At last, the knockdown of CaSR blocked the inhibition of osteoclast differentiation attributed to high Ca2+ e . Taken together, our findings indicate that high Ca2+ e inhibits osteoclast differentiation in RA mice partially through the CaSR/NF-κB/NFATc1 pathway.


Asunto(s)
Artritis Reumatoide , Receptores Sensibles al Calcio , Ratones , Animales , Receptores Sensibles al Calcio/genética , Calcio , Osteogénesis , FN-kappa B , Dieta
6.
Br J Dermatol ; 190(2): 244-257, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-37850885

RESUMEN

BACKGROUND: Psoriasis is a common chronic skin disorder. Pathologically, it features abnormal epidermal proliferation, infiltrating inflammatory cells and increased angiogenesis in the dermis. Aberrant expression of E3 ubiquitin ligase and a dysregulated protein ubiquitination system are implicated in the pathogenesis of psoriasis. OBJECTIVES: To examine the potential role of S-phase kinase-associated protein 2 (Skp2), an E3 ligase and oncogene, in psoriasis. METHODS: Gene expression and protein levels were evaluated with quantitative reverse transcriptase polymerase chain reaction, Western blotting, immunohistochemistry and immunofluorescence staining of skin samples from patients with psoriasis vulgaris and an imiquimod (IMQ)-induced mouse model, as well as from cultured endothelial cells (ECs). Protein interaction, substrate ubiquitination and degradation were examined using co-immunoprecipitation, Western blotting and a cycloheximide chase assay in human umbilical vein ECs. Angiogenesis was measured in vitro using human dermal microvascular ECs (HDMECs) for BrdU incorporation, migration and tube formation. In vivo angiogenesis assays included chick embryonic chorioallantoic membrane, the Matrigel plug assay and quantification of vasculature in the mouse lesions. Skp2 gene global knockout (KO) mice and endothelial-specific conditional KO mice were used. RESULTS: Skp2 was increased in skin samples from patients with psoriasis and IMQ-induced mouse lesions. Immunofluorescent double staining indicated a close association of Skp2 expression with excessive vascularity in the lesional dermal papillae. In HDMECs, Skp2 overexpression was enhanced, whereas Skp2 knockdown inhibited EC proliferation, migration and tube-like structure formation. Mechanistically, phosphatase and tensin homologue (PTEN), which suppresses the phosphoinositide 3-kinase/Akt pathway, was identified to be a novel substrate for Skp2-mediated ubiquitination. A selective inhibitor of Skp2 (C1) or Skp2 small interfering RNA significantly reduced vascular endothelial growth factor-triggered PTEN ubiquitination and degradation. In addition, Skp2-mediated ubiquitination depended on the phosphorylation of PTEN by glycogen synthase kinase 3ß. In the mouse model, Skp2 gene deficiency alleviated IMQ-induced psoriasis. Importantly, tamoxifen-induced endothelial-specific Skp2 KO mice developed significantly ameliorated psoriasis with diminished angiogenesis of papillae. Furthermore, topical use of the Skp2 inhibitor C1 effectively prevented the experimental psoriasis. CONCLUSIONS: The Skp2/PTEN axis may play an important role in psoriasis-associated angiogenesis. Thus, targeting Skp2-driven angiogenesis may be a potential approach to treating psoriasis.


Asunto(s)
Psoriasis , Proteínas Quinasas Asociadas a Fase-S , Humanos , Animales , Ratones , Proteínas Quinasas Asociadas a Fase-S/genética , Proteínas Quinasas Asociadas a Fase-S/metabolismo , Tensinas/metabolismo , Células Endoteliales/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Angiogénesis , Factor A de Crecimiento Endotelial Vascular/metabolismo , Psoriasis/patología , Ubiquitina-Proteína Ligasas/metabolismo
7.
Phys Chem Chem Phys ; 26(4): 3044-3050, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38180238

RESUMEN

The electrosynthesis of hydrogen peroxide (H2O2) offers a sustainable and viable option for generating H2O2 directly, as an alternative to the anthraquinone oxidation method. This study focuses on the comparative study of Co nanoparticles and single-atomic Co sites (Co SACs) that were encapsulated into nitrogen-doped carbon for the electrosynthesis of H2O2, which has been synthesized by direct pyrolysis of Zn/Co-ZIF or Co-based zeolitic imidazolate frameworks (ZIF-67). The electrochemical measurement results demonstrate that the coexistence of Co nanoparticles and single-atomic Co sites in the CoNC catalyst is more conducive for H2O2 production compared to Co SACs only, possessing better H2O2 selectivity of 73.3% and higher faradaic efficiency of 87%. The improved performance of CoNC with SACs can be attributed to the presence of additional Co nanoparticles in the nitrogen-doped carbon layers.

8.
Plant Cell Rep ; 43(5): 114, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587681

RESUMEN

KEY MESSAGE: SmZHDs was highly expressed in anthocyanin-rich parts of eggplant. SmZHD12 can activate the expression of SmCHS, SmANS, SmDFR and SmF3H. Overexpression of SmZHD12 promotes anthocyanin biosynthesis in Arabidopsis. The Zinc finger-homeodomain (ZHD) proteins family genes are known to play a significant role in plant development and physiological processes. However, the evolutionary history and function of the ZHD gene family in eggplant remain largely unexplored. This study categorizes a total of 15 SmZHD genes into SmMIF and SmZHD subfamilies based on conserved domains. The phylogeny, gene structure, conserved motifs, promoter elements, and chromosomal locations of the SmZHD genes were comprehensively analyzed. Tissue expression profiles indicate that the majority of SmZHD genes are expressed in anthocyanin-rich areas. qRT-PCR assays revealed distinct expression patterns of SmZHD genes in response to various treatments, indicating their potential involvement in multiple signaling pathways. Analysis of transcriptomic data from light-treated eggplant peel identified SmZHD12 as the most light-responsive gene among the 15 SmZHD genes. Consequently, this study provides further evidence that SmZHD12 facilitates anthocyanin accumulation in Arabidopsis leaves by upregulating the expression of anthocyanin biosynthesis structural genes, as confirmed by dual-luciferase assays and Arabidopsis genetic transformation. Our study will lay a solid foundation for the in-depth study of the involvement of SmZHD genes in the regulation of anthocyanin biosynthesis.


Asunto(s)
Arabidopsis , Solanum melongena , Solanum melongena/genética , Antocianinas , Arabidopsis/genética , Evolución Biológica , Perfilación de la Expresión Génica
9.
Oral Dis ; 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287672

RESUMEN

Intraflagellar transport (IFT) proteins have been reported to regulate cell growth and differentiation as the essential functional component of primary cilia. The effects of IFT80 on early bone healing of extraction sockets have not been well studied. To investigate whether deletion of Ift80 in alveolar bone-derived mesenchymal stem cells (aBMSCs) affected socket bone healing, we generated a mouse model of specific knockout of Ift80 in Prx1 mesenchymal lineage cells (Prx1Cre ;IFT80f/f ). Our results demonstrated that deletion of IFT80 in Prx1 lineage cells decreased the trabecular bone volume, ALP-positive osteoblastic activity, TRAP-positive osteoclastic activity, and OSX-/COL I-/OCN-positive areas in tooth extraction sockets of Prx1Cre ; IFT80f/f mice compared with IFT80f/f littermates. Furthermore, aBMSCs from Prx1Cre ; IFT80f/f mice showed significantly decreased osteogenic markers and downregulated migration and proliferation capacity. Importantly, the overexpression of TAZ recovered significantly the expressions of osteogenic markers and migration capacity of aBMSCs. Lastly, the local administration of lentivirus for TAZ enhanced the expression of RUNX2 and OSX and promoted early bone healing of extraction sockets from Prx1Cre ; IFT80f/f mice. Thus, IFT80 promotes osteogenesis and early bone healing of tooth sockets through the activation of TAZ/RUNX2 pathway.

10.
BMC Pediatr ; 24(1): 261, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38643075

RESUMEN

OBJECTIVE: To explore the relationship between body mass index (BMI ) and the severity of tic disorders (TDs) in children 6-14 years old. METHODS: A total of 86 children diagnosed with TDs in a hospital between Jan. 2023 and Sept. 2023 were collected by convenient sampling method, and the general data and TD-specific data were collected and analyzed. RESULTS: Univariate analysis showed that patients with different Yale Global Tic Severity Scale (YGTSS) grades had statistically significant differences in age, BMI, residence, snacking pattern, weekly physical exercise frequency, weekly physical exercise time, and proportion of cesarean birth. Multiple linear regression analysis showed that the YGTSS score grades were related to BMI, snacking pattern, and cesarean birth of the patients. Correlation analysis revealed a positive correlation between BMI grades and the YGTSS score grades, with a higher BMI indicating more severe TDs. Predictive value evaluation showed that BMI, snacking pattern, and cesarean birth had predictive values for TD severity, and the highest value was found in the combined prediction. CONCLUSION: BMI, snacking pattern, and cesarean birth are of predictive values for the severity of TDs. In addition, BMI is positively correlated with the severity of TDs, and a higher BMI suggests more severe TDs.


Asunto(s)
Trastornos de Tic , Niño , Humanos , Adolescente , Trastornos de Tic/diagnóstico , Índice de Masa Corporal , Índice de Severidad de la Enfermedad , Proyectos de Investigación , Ejercicio Físico
11.
Pestic Biochem Physiol ; 202: 105962, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38879310

RESUMEN

Lufenuron, a benzoylurea chitin synthesis inhibitor, is effective against many insect pests. However, the insecticidal activity of lufenuron has not been completely elucidated, nor has its disturbing effect on chitin synthesis genes. In this study, bioassay results demonstrated an outstanding toxicity of lufenuron against Helicoverpa armigera larvae. The treated larvae died from abortive molting and metamorphosis defects, and severe separation of epidermis and subcutaneous tissues was observed. Treatment of 3rd- and 4th-instar larvae with LC25 lufenuron significantly extended the duration of larval and pupal stage, reduced the rates of pupation and emergence, and adversely affected pupal weight. Besides, lufenuron can severely reduce chitin content in larval integument, and the lufenuron-treated larvae showed reduced trehalose content in their hemolymph. Further analysis using RNA sequencing revealed that five chitin synthesis genes were down-regulated, whereas the expressions of two chitin degradation genes were significantly enhanced. Knockdown of chitin synthase 1 (HaCHS1), uridine diphosphate-N-acetylglucosamine-pyrophosphorylase (HaUAP), phosphoacetyl glucosamine mutase (HaPGM), and glucosamine 6-phosphate N-acetyl-transferase (HaGNPAT) in H. armigera led to significant increase in larval susceptibilities to LC25 lufenuron by 75.48%, 65.00%, 68.42% and 28.00%, respectively. Our findings therefore revealed the adverse effects of sublethal doses of lufenuron on the development of H. armigera larvae, elucidated the perturbations on chitin metabolism, and proved that the combination of RNAi and lufenuron would improve the control effect of this pest.


Asunto(s)
Benzamidas , Quitina , Insecticidas , Larva , Mariposas Nocturnas , Animales , Quitina/biosíntesis , Benzamidas/farmacología , Larva/efectos de los fármacos , Insecticidas/farmacología , Insecticidas/toxicidad , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/metabolismo , Mariposas Nocturnas/crecimiento & desarrollo , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Quitina Sintasa/metabolismo , Quitina Sintasa/genética , Helicoverpa armigera , Fluorocarburos
12.
Environ Toxicol ; 39(3): 1456-1470, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37987463

RESUMEN

The disorders of endometrial receptivity and ovulatory dysfunction are both significant causes of infertility in patients with polycystic ovary syndrome (PCOS). In this study, we investigated the expression profile and functional implications of circular RNAs (circRNAs) in the endometrial receptivity of PCOS-affected mice. Twenty-four female C57BL/6 mice were divided into PCOS and normal control groups. The PCOS group received subcutaneous DHEA treatment, while the control group remained untreated. Gene chip technology was utilized to analyze circRNA expression in endometrial tissues on the fourth day of gestation with subsequent bioinformatics analyses into circRNA functions. Furthermore, endometrial epithelial cells were used to determine represented circRNA functions. Results showed that the PCOS group exhibited 205 differentially expressed circRNAs, with 147 upregulated and 58 downregulated ones. qRT-PCR confirmed differential expression of circRNAs, including circRNA_38548, circRNA_001686, circRNA_38550, and circRNA_27938. Predicted target genes and a circRNA-miRNA-mRNA regulatory network were constructed. Additionally, four circRNAs (circRNA_38548, circRNA_38550, and circRNA_001686) were identified to contribute to abnormal endometrial receptivity by regulating genes such as Lifr, FOXK1, FOXO1, HOXA10, through interactions with miRNAs. Further research is warranted to elucidate the underlying mechanisms involving these circRNAs.


Asunto(s)
MicroARNs , Síndrome del Ovario Poliquístico , Humanos , Femenino , Animales , Ratones , ARN Circular/metabolismo , Síndrome del Ovario Poliquístico/genética , Ratones Endogámicos C57BL , MicroARNs/genética , Perfilación de la Expresión Génica/métodos , Factores de Transcripción Forkhead
13.
Angew Chem Int Ed Engl ; 63(8): e202319090, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38179862

RESUMEN

Localized high-concentration electrolyte is widely acknowledged as a cutting-edge electrolyte for the lithium metal anode. However, the high fluorine content, either from high-concentration salts or from highly fluorinated diluents, results in significantly higher production costs and an increased environmental burden. Here, we have developed a novel electrolyte termed "Localized Medium-Concentration Electrolyte" (LMCE) to effectively address these issues. This LMCE is designed and produced by diluting a medium concentration (0.5 M-1.5 M) electrolyte which is incompatible with lithium metal anode before diluting. It has ultralow concentration (0.1 M) and demonstrates remarkable compatibility with lithium metal anode. Surprisingly, our LMCE, despite having an ultralow concentration (0.1 M), exhibits excellent kinetics in Li/Cu, Li/Li, LiFePO4 /Li, and NCM811/Li batteries. Additionally, LMCE effectively inhibits the corrosion of the Al current collector caused by LiTFSI salt under high voltage (>4 V) conditions. This groundbreaking LMCE design transforms the seemingly "incompatible" into the "compatible", opening up new avenues for exploring various electrolyte formulations, including all liquid electrolyte-based batteries.

14.
J Mol Evol ; 91(2): 156-168, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36859501

RESUMEN

Tea, which is processed by the tender shoots or leaves of tea plant (Camellia sinensis), is one of the most popular nonalcoholic beverages in the world and has numerous health benefits for humans. Along with new progress in biotechnologies, the refined chromosome-scale reference tea genomes have been achieved, which facilitates great promise for the understanding of fundamental genomic architecture and evolution of the tea plants. Here, we summarize recent achievements in genome sequencing in tea plants and review the new progress in origin and evolution of tea plants by population sequencing analysis. Understanding the genomic characterization of tea plants is import to improve tea quality and accelerate breeding in tea plants.


Asunto(s)
Camellia sinensis , Humanos , Camellia sinensis/genética , Genómica , Genoma de Planta/genética , Análisis de Secuencia de ADN , Té/genética
15.
Magn Reson Med ; 89(2): 746-755, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36198043

RESUMEN

PURPOSE: To determine if contemporary 0.55 T MRI supports the use of contrast-optimal flip angles (FA) for simultaneous multi-slice (SMS) balanced SSFP (bSSFP) cardiac function assessment, which is impractical at conventional field strengths because of excessive SAR and/or banding artifacts. METHODS: Blipped-CAIPI bSSFP was combined with spiral sampling for ventricular function assessment at 0.55 T. Cine movies with single band and SMS factors of 2 and 3 (SMS 2 and 3), and FA ranging from 60° to 160°, were acquired in seven healthy volunteers. Left ventricular blood and myocardial signal intensity (SI) normalized by background noise and blood-myocardium contrast were measured and compared across acquisition settings. RESULTS: Myocardial SI was slightly higher in single band than in SMS and decreased with an increasing FA. Blood SI increased as the FA increased for single band, and increment was small for FA ≥120°. Blood SI for SMS 2 and 3 increased with an increasing FA up to ∼100°. Blood-myocardium contrast increased with an increasing FA for single band, peaked at FA = 160° (systole: 28.43, diastole: 29.15), attributed mainly to reduced myocardial SI when FA ≥120°. For SMS 2, contrast peaked at 120° (systole: 21.43, diastole: 19.85). For SMS 3, contrast peaked at 120° in systole (16.62) and 100° in diastole (19.04). CONCLUSIONS: Contemporary 0.55 T MR scanners equipped with high-performance gradient systems allow the use of contrast-optimal FA for SMS accelerated bSSFP cine examinations without compromising image quality. The contrast-optimal FA was found to be 140° to 160° for single band and 100° to 120° for SMS 2 and 3.


Asunto(s)
Corazón , Interpretación de Imagen Asistida por Computador , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Corazón/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Ventrículos Cardíacos , Miocardio , Imagen por Resonancia Cinemagnética/métodos
16.
BMC Pediatr ; 23(1): 483, 2023 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-37741963

RESUMEN

BACKGROUND: The morbidity of type 1 diabetes mellitus (T1DM) in children is increasing and diabetic peripheral neuropathy (DPN) is one of the main microvascular complications of T1DM. The aim of this study was to explore sympathetic skin response (SSR) characteristics in children with T1DM and analyze the value of early diagnosis and follow-up in T1DM complicated with DPN. METHODS: Our prospective study enrolling 85 participants diagnosed with T1DM and 30 healthy controls (HCs) in the Children's Hospital of Hebei Province from 2017 to 2020. Compared the outcomes of SSR and nerve conduction study (NCS) in T1DM, and evaluated the variations in SSR and NCS of different durations, as well as changes after six months of therapy. RESULTS: SSR latency of T1DM group showed statistical difference as compared to HCs (p < 0.05). The SSR test was more sensitive than the NCS test in the early diagnosis of T1DM with DPN (p < 0.05). The abnormal rates of SSR and NCS in long duration of disease were higher than those in short duration of disease (p < 0.05). Among 65 participants with diabetic neuropathy, the onset latencies of SSR were shortened and the NCS were improved after treatment (p < 0.05). CONCLUSIONS: SSR could provide the accurate early diagnosis and follow-up of pediatric diabetic peripheral neuropathy.


Asunto(s)
Diabetes Mellitus Tipo 1 , Neuropatías Diabéticas , Enfermedades del Sistema Nervioso Periférico , Niño , Humanos , Diabetes Mellitus Tipo 1/complicaciones , Neuropatías Diabéticas/diagnóstico , Neuropatías Diabéticas/etiología , Diagnóstico Precoz , Estudios de Seguimiento , Estudios Prospectivos , Respuesta Galvánica de la Piel
17.
Zhonghua Nan Ke Xue ; 29(6): 543-551, 2023 Jun.
Artículo en Zh | MEDLINE | ID: mdl-38602729

RESUMEN

Chronic prostatitis is a common disease in male clinics. The theory of "brain-centre-kidney-vessel" axisis based on the basic theories of traditional Chinese medicine, the pathogenesis of modern men's diseases, and the theory of traditional Chinese medicine in men's medicine proposed by clinical practice. It takes the "brain-heart-kidney-vessel" axis as the entry point, the use of the vessel as the core pathogenesis, the meridians as the link, and the dysfunction of the brain, heart, and kidneys as the important conditions, and proposes that the biological basis between chronic prostatitis and the "brain-heart-kidney-vessel" axis is related to neurological, endocrine, and immunological disorders, as well as the biological basis of the "brain-heart-kidney-vessel" axis. It is also suggested that the biological basis between chronic prostatitis and the "brain-heart-kidney-sperm chamber" axis is related to the nerves, endocrine, immune and microenvironment. Through in-depth study of the biological basis of the "brain-cardiac-kidney-peritoneum" axis, we can better understand the pathogenesis of chronic prostatitis and provide reference for future clinical treatment.


Asunto(s)
Sistema Cardiovascular , Prostatitis , Masculino , Humanos , Semen , Riñón , Enfermedad Crónica , Encéfalo
18.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(9): 929-935, 2023.
Artículo en Zh | MEDLINE | ID: mdl-37718398

RESUMEN

OBJECTIVES: To explore the value of sympathetic skin response (SSR) in the early diagnosis and prognostic evaluation of Guillain-Barre syndrome (GBS) in children. METHODS: A retrospective analysis was conducted on the clinical data of 25 children with GBS who were diagnosed from October 2018 to November 2022, and 30 children who were diagnosed with Tourette's syndrome during the same period were selected as the control group. The characteristics of SSR were compared between the two groups, and the association of SSR with autonomic dysfunction (AD), disease severity, and prognosis was analyzed. RESULTS: The GBS group had a significantly higher abnormal rate of SSR than the control group during the acute phase (P<0.001). SSR combined with early nerve conduction (within 2 weeks after onset) had a sensitivity of 84%, a specificity of 100%, and an accuracy of 93% in the diagnosis of GBS. There were no significant differences in the proportion of AD cases, as well as the Hughes scores during the disease peak, between the abnormal and normal SSR groups (P>0.05). All 7 children with poor short-term prognosis (at 1 month after onset) had abnormal SSR. CONCLUSIONS: SSR can be used for the early diagnosis of GBS and the monitoring of treatment response in children.

19.
Biol Pharm Bull ; 45(12): 1743-1753, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36130913

RESUMEN

Delavatine A (DA) is an unusual isoquinoline alkaloid with a novel skeleton isolated from Chinese folk medicine Incarvillea delavayi. Studies conducted in our lab have demonstrated that DA has potential anti-inflammatory activity in lipopolysaccharide (LPS)-treated BV-2 cells. DA, however, has not been studied for its protective effect on neuronal cells yet. Thus, to explore whether DA can protect neurons, oxygen and glucose deprivation/reperfusion (OGD/R)-injured PC12 cell and middle cerebral artery occlusion/reperfusion (MCAO/R) rat model were used to assess the protective efficacy of DA against OGD/R damaged PC12 cells and MCAO/R injured rats. Our results demonstrated that DA pretreatment (0.31-2.5 µM) dose-dependently increased cell survival and mitochondrial membrane potential (MMP), whereas it lowered the leakage of lactate dehydrogenase (LDH), intracellular cumulation of Ca2+, and overproduction of reactive oxygen species (ROS), and inhibited the apoptosis rate in OGD/R-injured PC12 cells. Western blot demonstrated that DA pretreatment lowered the expression of apoptotic proteins and repressed the activation of the mitogen-activated protein kinase kinase 7 (MKK7)/c-Jun N-terminal kinase (JNK) pathway. It was also found that the neuroprotective efficacy of DA was significantly reversed by co-treatment with the JNK agonist anisomycin, suggesting that DA reduced PC12 cell injury and apoptosis by suppressing the MKK7/JNK pathway. Furthermore, DA oral administration greatly alleviated the neurological dysfunction and reduced the infarct volume of MCAO/R rats. Taken together, DA could ameliorate OGD/R-caused PC12 cell injury and improve brain ischemia/reperfusion (I/R) damage in MCAO/R rats, and its neuroprotection might be attributed to suppressing the MKK7/JNK signaling pathway.


Asunto(s)
Fármacos Neuroprotectores , Daño por Reperfusión , Animales , Ratas , Células PC12 , Glucosa/metabolismo , Oxígeno/metabolismo , Sistema de Señalización de MAP Quinasas , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Daño por Reperfusión/metabolismo , Apoptosis , Reperfusión
20.
Magn Reson Med ; 85(6): 3182-3195, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33452722

RESUMEN

PURPOSE: To provide 3D real-time MRI of speech production with improved spatio-temporal sharpness using randomized, variable-density, stack-of-spiral sampling combined with a 3D spatio-temporally constrained reconstruction. METHODS: We evaluated five candidate (k, t) sampling strategies using a previously proposed gradient-echo stack-of-spiral sequence and a 3D constrained reconstruction with spatial and temporal penalties. Regularization parameters were chosen by expert readers based on qualitative assessment. We experimentally determined the effect of spiral angle increment and kz temporal order. The strategy yielding highest image quality was chosen as the proposed method. We evaluated the proposed and original 3D real-time MRI methods in 2 healthy subjects performing speech production tasks that invoke rapid movements of articulators seen in multiple planes, using interleaved 2D real-time MRI as the reference. We quantitatively evaluated tongue boundary sharpness in three locations at two speech rates. RESULTS: The proposed data-sampling scheme uses a golden-angle spiral increment in the kx -ky plane and variable-density, randomized encoding along kz . It provided a statistically significant improvement in tongue boundary sharpness score (P < .001) in the blade, body, and root of the tongue during normal and 1.5-times speeded speech. Qualitative improvements were substantial during natural speech tasks of alternating high, low tongue postures during vowels. The proposed method was also able to capture complex tongue shapes during fast alveolar consonant segments. Furthermore, the proposed scheme allows flexible retrospective selection of temporal resolution. CONCLUSION: We have demonstrated improved 3D real-time MRI of speech production using randomized, variable-density, stack-of-spiral sampling with a 3D spatio-temporally constrained reconstruction.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Habla , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Estudios Retrospectivos , Lengua/diagnóstico por imagen
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