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1.
BMC Genomics ; 25(1): 203, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38389079

RESUMEN

BACKGROUND: Firmiana danxiaensis is a critically endangered and ecologically important tree currently only found in four locations in Danxia or Karst habitats in northern Guangdong Province, China. The specialized habitat preference makes it an ideal model species for study of adaptive evolution. Meanwhile, the phylogenetic relationships of F. danxiaensis in four locations under two landforms are unclear. Therefore, we sequenced its complete chloroplast (cp.) genomes and conducted comprehensive interspecific and intrageneric plastome studies. RESULTS: The F. danxiaensis plastomes in four locations showed a typical quadripartite and circular structure that ranged from 160,832 to 161,206 bp in size, with 112 unique genes encoded. Comparative genomics showed that the plastomes of F. danxiaensis were relatively conserved with high similarity of genome organization, gene number, GC content and SSRs. While the genomes revealed higher biased codon preferences in Karst habitat than those in Danxia habitats. Eighteen and 11 divergent hotpots were identified at interspecific and intrageneric levels for species identification and further phylogenetic studies. Seven genes (clpP, accD, ccsA, ndhH, rpl20, rpoC2, and rps4) were under positive selection and may be related to adaptation. Phylogenetic analysis revealed that F. danxiaensis is sister to F. major and F. simplex. However, the interspecific relationships are not consistent with the habitat types. CONCLUSIONS: The characteristics and interspecific relationship of F. danxiaensis plastomes provide new insights into further integration of geographical factors, environmental factors, and genetic variations on the genomic study of F. danxiaensis. Together, our study will contribute to the study of species identification, population genetics, and conservation biology of F. danxiaensis.


Asunto(s)
Genoma del Cloroplasto , Filogenia , Genoma del Cloroplasto/genética , Genómica , Secuencia de Bases , Genética de Población
2.
Opt Lett ; 49(1): 69-72, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134154

RESUMEN

Insensitivity to external optical feedback is experimentally demonstrated in a self-chaotic deformed square microcavity laser for the first time, to the best of our knowledge. Both the optical and radio frequency (RF) spectra of the microlaser remain unaffected for external optical feedback with feedback strength as high as 9.9 dB. In addition, the autocorrelation function curve exhibits no time-delayed peaks. The insensitivity makes the self-chaotic microcavity laser promising for applications in feedback-insensitive optical sources.

3.
J Magn Reson Imaging ; 59(2): 599-610, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37203312

RESUMEN

BACKGROUND: Diffusion magnetic resonsance imaging (dMRI) can potentially predict the postoperative outcome of cervical spondylotic myelopathy (CSM). PURPOSE: To explore preoperative dMRI parameters to predict the postoperative outcome of CSM through multifactor correlation analysis. STUDY TYPE: Prospective. POPULATION: Post-surgery CSM patients; 102 total, 73 male (52.42 ± 10.60 years old) and 29 female (52.0 ± 11.45 years old). FIELD STRENGTH/SEQUENCE: 3.0 T/Turbo spin echo T1/T2-weighted, T2*-weighted multiecho gradient echo and dMRI. ASSESSMENT: Spinal cord function was evaluated using modified Japanese Orthopedic Association (mJOA) scoring at different time points: preoperative and 3, 6, and 12 months postoperative. Single-factor correlation and t test analyses were conducted based on fractional anisotropy (FA), mean diffusivity, intracellular volume fraction, isotropic volume fraction, orientation division index, increased signal intensity, compression ratio, age, sex, symptom duration and operation method, and multicollinearity was calculated. The linear quantile mixed model (LQMM) and the linear mixed-effects regression model (LMER) were used for multifactor correlation analysis using the combinations of the above variables. STATISTICAL TESTS: Distance correlation, Pearson's correlation, multiscale graph correlation and t tests were used for the single-factor correlation analyses. The variance inflation factor (VIF) was used to calculate multicollinearity. LQMM and LMER were used for multifactor correlation analyses. P < 0.05 was considered statistically significant. RESULTS: The single-factor correlation between all variables and the postoperative mJOA score was weak (all r < 0.3). The linear relationship was stronger than the nonlinear relationship, and there was no significant multicollinearity (VIF = 1.10-1.94). FA values in the LQMM and LMER models had a significant positive correlation with the mJOA score (r = 5.27-6.04), which was stronger than the other variables. DATA CONCLUSION: The FA value based on dMRI significantly positively correlated with CSM patient postoperative outcomes, helping to predict the surgical outcome and formulate a treatment plan before surgery. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Enfermedades de la Médula Espinal , Espondilosis , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Estudios Prospectivos , Imagen de Difusión Tensora/métodos , Espondilosis/diagnóstico por imagen , Espondilosis/cirugía , Espondilosis/patología , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/cirugía , Imagen por Resonancia Magnética , Imagen de Difusión por Resonancia Magnética , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Resultado del Tratamiento
4.
Langmuir ; 40(19): 10305-10312, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38696716

RESUMEN

The limited elasticity and inadequate bonding of hydrogels made from guar gum (GG) significantly hinder their widespread implementation in personalized wearable flexible electronics. In this study, we devise GG-based self-adhesive hydrogels by creating an interpenetrating network of GG cross-linked with acrylic, 4-vinylphenylboronic acid, and Ca2+. With the leverage of the dynamic interactions (hydrogen bonds, borate ester bonds, and coordination bonds) between -OH in GG and monomers, the hydrogel exhibits a high stretchability of 700%, superior mechanical stress of 110 kPa, and robust adherence to several substrates. The adhesion strength of 54 kPa on porcine skin is obtained. Furthermore, the self-adhesive hydrogel possesses stable conductivity, an elevated gauge factor (GF), and commendable durability. It can be affixed to the human body as a strain sensor to obtain precise monitoring of human movement behavior. Our research offers possibilities for the development of GG-based hydrogels and applications in wearable electronics and medical monitoring.


Asunto(s)
Conductividad Eléctrica , Galactanos , Hidrogeles , Mananos , Gomas de Plantas , Hidrogeles/química , Mananos/química , Gomas de Plantas/química , Galactanos/química , Animales , Dispositivos Electrónicos Vestibles , Humanos , Porcinos , Adhesivos/química
5.
Environ Sci Technol ; 58(18): 7891-7903, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38602183

RESUMEN

Tropospheric nitrogen dioxide (NO2) poses a serious threat to the environmental quality and public health. Satellite NO2 observations have been continuously used to monitor NO2 variations and improve model performances. However, the accuracy of satellite NO2 retrieval depends on the knowledge of aerosol optical properties, in particular for urban agglomerations accompanied by significant changes in aerosol characteristics. In this study, we investigate the impacts of aerosol composition on tropospheric NO2 retrieval for an 18 year global data set from Global Ozone Monitoring Experiment (GOME)-series satellite sensors. With a focus on cloud-free scenes dominated by the presence of aerosols, individual aerosol composition affects the uncertainties of tropospheric NO2 columns through impacts on the aerosol loading amount, relative vertical distribution of aerosol and NO2, aerosol absorption properties, and surface albedo determination. Among aerosol compositions, secondary inorganic aerosol mostly dominates the NO2 uncertainty by up to 43.5% in urban agglomerations, while organic aerosols contribute significantly to the NO2 uncertainty by -8.9 to 37.3% during biomass burning seasons. The possible contrary influences from different aerosol species highlight the importance and complexity of aerosol correction on tropospheric NO2 retrieval and indicate the need for a full picture of aerosol properties. This is of particular importance for interpreting seasonal variations or long-term trends of tropospheric NO2 columns as well as for mitigating ozone and fine particulate matter pollution.


Asunto(s)
Aerosoles , Contaminantes Atmosféricos , Monitoreo del Ambiente , Dióxido de Nitrógeno , Estaciones del Año , Dióxido de Nitrógeno/análisis , Contaminantes Atmosféricos/análisis , Ozono/análisis
6.
Mol Biol Rep ; 51(1): 371, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38411728

RESUMEN

BACKGROUND: Cockayne syndrome is an inherited heterogeneous defect in transcription-coupled DNA repair (TCR) cause severe clinical syndromes, which may affect the nervous system development of infants and even lead to premature death in some cases. ERCC8 diverse critical roles in the nucleotide excision repair (NER) complex, which is one of the disease-causing genes of Cockayne syndrome. METHODS AND RESULTS: The mutation of ERCC8 in the patient was identified and validated using WES and Sanger sequencing. Specifically, a compound heterozygous mutation (c.454_460dupGTCTCCA p. T154Sfs*13 and c.755_759delGTTTT p.C252Yfs*3) of ERCC8 (CSA) was found, which could potentially be the genetic cause of Cockayne syndrome in the proband. CONCLUSION: In this study, we identified a novel heterozygous mutation of ERCC8 in a Chinese family with Cockayne syndrome, which enlarging the genetic spectrum of the disease.


Asunto(s)
Síndrome de Cockayne , Humanos , Pueblo Asiatico , Núcleo Celular , Síndrome de Cockayne/genética , Enzimas Reparadoras del ADN/genética , Reparación por Escisión , Mutación/genética , Factores de Transcripción
7.
Macromol Rapid Commun ; : e2400279, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816757

RESUMEN

Hydrogel-based wearable sensors eventually experience dehydration, which negatively impacts their function, leading to decreased sensitivity. Monitoring the real-time water retention rate and sensing performance of wearable flexible sensors without dismantling them remains a significant difficulty. In this study, a molecule having aggregation-induced emission (AIE) properties in an aqueous environment has been developed and produced, which can combine with anionic guar gum and acrylic acid to create an AIE hydrogel. Wearable sensing electronic devices have the capability to track motion signals at various joints of the human body. Additionally, they can effectively and visually monitor dehydration status during extended periods of operation. The fluorescence intensity of the hydrogel is primarily influenced by the level of aggregation of luminous monomers inside the network. This level of aggregation is predominantly governed by the hydrogel's water retention rate. Hence, the extended duration of hydrogel dehydration can be manifested through alterations in their fluorescence characteristics, which are employed for strain sensing. This approach enables users to assess the water retention of hydrogels with greater efficiency, eliminating the requirement for disassembling them from the completed electrical gadget. In summary, the use of AIE-based fluorescent hydrogels will advance the progress of intelligent wearable electronics.

8.
Regul Toxicol Pharmacol ; 149: 105617, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38561146

RESUMEN

Accumulating evidence has shown that the abnormal toxicity test (ATT) is not suitable as a quality control batch release test for biologics and vaccines. The purpose of the current study was to explore the optimal ATT experimental design for an adenoviral vector-based vaccine product to avoid false positive results following the standard test conditions stipulated in the Pharmacopoeias. ATT were conducted in both mice and guinea pigs based on methods in Pharmacopeias, with modifications to assess effects of dose volume and amount of virus particles (VPs). The results showed intraperitoneal (IP) dosing at human relevant dose and volume (i.e., VPs), as required by pharmacopeia study design, resulted in false positive findings not associated with extraneous contaminants of a product. Considering many gene therapy products use adeno associated virus as the platform for transgene delivery, data from this study are highly relevant in providing convincing evidence to show the ATT is inappropriate as batch release test for biologics, vaccine and gene therapy products. In conclusion, ATT, which requires unnecessary animal usage and competes for resources which otherwise can be spent on innovative medicine research, should be deleted permanently as batch release test by regulatory authorities around the world.


Asunto(s)
Vectores Genéticos , Pruebas de Toxicidad , Animales , Cobayas , Pruebas de Toxicidad/métodos , Ratones , Reacciones Falso Positivas , Femenino , Adenoviridae/genética , Masculino , Vacunas
9.
Food Microbiol ; 120: 104489, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38431332

RESUMEN

Aeromonas veronii is associated with food spoilage and some human diseases, such as diarrhea, gastroenteritis, hemorrhagic septicemia or asymptomatic and even death. This research investigated the mechanism of the growth, biofilm formation, virulence, stress resistance, and spoilage potential of Bacillus subtilis lipopeptide against Aeromonas veronii. Lipopeptides suppressed the transmembrane transport of Aeromonas veronii by changing the cell membrane's permeability, the structure of membrane proteins, and Na+/K+-ATPase. Lipopeptide significantly reduced the activities of succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) by 86.03% and 56.12%, respectively, ultimately slowing Aeromonas veronii growth. Lipopeptides also restrained biofilm formation by inhibiting Aeromonas veronii motivation and extracellular polysaccharide secretion. Lipopeptides downregulated gene transcriptional levels related to the virulence and stress tolerance of Aeromonas veronii. Furthermore, lipopeptides treatment resulted in a considerable decrease in the extracellular protease activity of Aeromonas veronii, which restrained the decomposing of channel catfish flesh. This research provides new insights into lipopeptides for controlling Aeromonas veronii and improving food safety.


Asunto(s)
Aeromonas , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Ictaluridae , Animales , Humanos , Aeromonas veronii/genética , Aeromonas veronii/metabolismo , Bacillus subtilis/genética , Biopelículas , Lipopéptidos/farmacología , Lipopéptidos/metabolismo , Infecciones por Bacterias Gramnegativas/genética , Aeromonas/genética
10.
Anim Biotechnol ; 35(1): 2335340, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38587818

RESUMEN

This study explored the effects of different vitamin B5 (VB5) levels on intestinal growth and function of weaned piglets. Twenty-one piglets (7.20 ± 1.11 kg) were included in a 28-day feeding trial with three treatments, including 0 mg/kg (L-VB5), 10 mg/kg (Control) and 50 mg/kg (H-VB5) of VB5 supplement. The results showed that: Large intestine weight/body weight was the highest in H-VB5 group, Control and H-VB5 groups had significantly higher villus height and villus height/crypt depth than the L-VB5 in the ileum (p < .05). Goblet cells (ileal crypt) and endocrine cells (ileal villus) significantly increased in Control and H-VB5 (p < .05). The H-VB5 group exhibited significantly higher levels of ki67 and crypt depth in the cecum and colon, colonic goblet cells and endocrine cells were both rising considerably (p < .05). Isobutyric acid and isovaleric acid were significantly reduced in the H-VB5 group (p < .05), and there was a decreasing trend in butyric acid (p = .073). At the genus level, the relative abundance of harmful bacteria such as Clostridium_Sensu_Structo_1 Strecto_1, Terrisporbacter and Streptococcus decreased significantly and the relative abundance of beneficial bacteria Turicibacter increased significantly in H-VB5 group (p < .05). Overall, the addition of 50 mg/kg VB5 primarily enhanced the morphological structure, cell proliferation and differentiation of the ileum, cecum and colon. It also had a significant impact on the gut microbiota and short-chain fatty acids.


Asunto(s)
Ciego , Ácido Pantoténico , Animales , Ácido Butírico , Diferenciación Celular , Suplementos Dietéticos , Porcinos
11.
Arch Gynecol Obstet ; 310(1): 181-194, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38782764

RESUMEN

PURPOSE: The identification and prognosis of the agenesis of the corpus callosum (ACC) for prenatal consultation are complex and currently unclear. This study aims to explore the correlated genetic mutations of prenatal ACC. METHODS: We retrospectively analyzed 114 prenatal cases of ACC. All cases (n = 114) were subjected to chromosomal microarray analysis (CMA), and 66 CMA-negative cases underwent prenatal exome sequencing (pES) for further analysis. RESULTS: CMA was diagnosed positively in 15/114 (13.2%) cases and pES was diagnosed positively in 24/66 (36.4%) CMA-negative cases. The detection rate of genetic causes between complete and partial ACCs was not significantly different (P > 0.05). Between isolated and non-isolated (other anomalies present) ACCs, the diagnostic rate of pES in non-isolated cases was significantly higher (P < 0.001), while CMA results did not differ (P > 0.05). The diagnostic rate of CMA was significantly increased in cases combined with intracranial and extracranial malformations (P = 0.014), while no CMA positivity was detected in cases combined with only intracranial malformations. CONCLUSION: For fetuses with prenatal ACC, further pES analysis should be recommended after negative CMA results. Chromosome abnormalities are less likely to occur when ACC with only intracranial malformations combined.


Asunto(s)
Agenesia del Cuerpo Calloso , Humanos , Estudios Retrospectivos , Femenino , Agenesia del Cuerpo Calloso/genética , Agenesia del Cuerpo Calloso/diagnóstico , Embarazo , Adulto , Análisis por Micromatrices , Diagnóstico Prenatal , Secuenciación del Exoma , Aberraciones Cromosómicas/embriología , Aberraciones Cromosómicas/estadística & datos numéricos , Ultrasonografía Prenatal
12.
Nano Lett ; 23(14): 6474-6481, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37428132

RESUMEN

In this work, an ordered membrane electrode assembly (MEA) based on a cone Nafion array with gradient Nafion distribution, tightly bonded catalytic layer/proton exchange membrane (CL/PEM) interface, and abundant vertical channels has been engineered by an anodic aluminum oxide template and magnetron sputtering method. Benefiting from a highly efficient CL/PEM interface, plentiful proton transfer highways, and rapid oxygen bubble release, this ordered MEA achieves an ultralow Ir loading of 20.0 µg cm-2 and a high electrochemical active area by 8.7 times compared to traditional MEA with Ir loading of 1.0 mg cm-2. It yields a mass activity of 168 000 mA mgIr-1 cm-2 at 2.0 V, which is superior to most reported PEM electrolyzers. Notably, this ordered MEA maintains excellent durability at a current density of 500 mA cm-2. This work opens a simple, cost-effective, and scalable route to design ordered MEAs for proton exchange membrane water electrolysis.

13.
Nurs Ethics ; : 9697330241255933, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38910258

RESUMEN

BACKGROUND: Stretch service goals strive to motivate healthcare practitioners to maintain high quality in service provision. However, little is known about how stretch service goals trigger nurses' unethical behavior. RESEARCH AIM: This study aimed to investigate the influence of stretch service goals on nurses' unethical behavior, as well as the mediating effects of patient entitlement and nurses' emotional dissonance. RESEARCH DESIGN: A quantitative cross-sectional study is designed. PARTICIPANTS AND RESEARCH CONTEXT: We sourced data by conducting a time-lagged three-wave survey study from March to September 2020. Random sampling was used, and data were collected from 422 nurse-patient pairs in Chinese hospitals. Bootstrapping method and structural equation modeling were employed to verify the conceptual model. ETHICAL CONSIDERATIONS: The study was approved by the designated authority within hospitals and ethical committees. RESULTS: Stretch service goals are not directly related to nurses' unethical behavior. Stretch service goals can trigger nurses' unethical behavior via patient entitlement. Patient entitlement and nurses' emotional dissonance play a chain-mediating role between stretch service goals and nurses' unethical behavior. CONCLUSIONS: In the context of the healthcare industry, nurses may engage in unethical behavior due to the pressure of achieving stretch service goals. This study contributes to opening the "black box" of stretch service goals and nurses' unethical behavior by exploring the chain-mediating effect of patient entitlement and nurses' emotional dissonance.

14.
Angew Chem Int Ed Engl ; : e202407757, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38978264

RESUMEN

On the basis of a novel ynol-diene cyclization developed as a rapid access to tropone unit, the first divergent strategy to 17-nor-cephalotane diterpenoids has been successfully established. Combining with a bioinspired stereoselective dual hydrogenation, the divergent total synthesis of (+)-3-deoxyfortalpinoid F, (+)-harringtonolide, (-)-fortalpinoids M/N/P, and analog (-)-20-deoxocephinoid P have been achieved in 14-17 linear longest steps starting from commercially available materials.

15.
Plant J ; 111(4): 1123-1138, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35763512

RESUMEN

Brassica napus is an important oil crop and an allotetraploid species. However, the detailed analysis of gene function and homoeologous gene expression in all tissues at different developmental stages was not explored. In this study, we performed a global transcriptome analysis of 24 vegetative and reproductive tissues at six developmental stages (totally 111 tissues). These samples were clustered into eight groups. The gene functions of silique pericarp were similar to roots, stems and leaves. In particular, glucosinolate metabolic process was associated with root and silique pericarp. Genes involved in protein phosphorylation were often associated with stamen, anther and the early developmental stage of seeds. Transcription factor (TF) genes were more specific than structural genes. A total of 17 100 genes that were preferentially expressed in one tissue (tissue-preferred genes, TPGs), including 889 TFs (5.2%), were identified in the 24 tissues. Some TPGs were identified as hub genes in the co-expression network analysis, and some TPGs in different tissues were involved in different hormone pathways. About 67.0% of the homoeologs showed balanced expression, whereas biased expression of homoeologs was associated with structural divergence. In addition, the spatiotemporal expression of homoeologs was related to the presence of transposable elements (TEs) and regulatory elements (REs); more TEs and fewer REs in the promoters resulted in divergent expression in different tissues. This study provides a valuable transcriptional map for understanding the growth and development of B. napus, for identifying important genes for future crop improvement, and for exploring gene expression patterns in the B. napus.


Asunto(s)
Brassica napus , Brassica napus/genética , Brassica napus/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica de las Plantas/genética , Hojas de la Planta , Semillas/genética , Transcriptoma
16.
Biol Reprod ; 108(3): 408-422, 2023 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-36617174

RESUMEN

Recurrent pregnancy loss (RPL) is a common pathological problem during pregnancy, and its clinical etiology is complex and unclear. Dysfunction of trophoblasts may cause a series of pregnancy complications, including preeclampsia, fetal growth restriction, and RPL. Recently, lncRNAs have been found to be closely related to the occurrence and regulation of pregnancy-related diseases, but few studies have focused on their role in RPL. In this study, we identified a novel lncRNA BBOX1-AS1 that was significantly upregulated in villous tissues and serum of RPL patients. Functionally, BBOX1-AS1 inhibited proliferation, migration, invasion, tube formation and promoted apoptosis of trophoblast cells. Mechanistically, overexpression of BBOX1-AS1 activated the p38 and JNK MAPK signaling pathways by upregulating GADD45A expression. Further studies indicated that BBOX1-AS1 could increase the stability of GADD45A mRNA by binding hnRNPK and ultimately cause abnormal trophoblast function. Collectively, our study highlights that the BBOX1-AS1/hnRNPK/GADD45A axis plays an important role in trophoblast-induced RPL and that BBOX1-AS1 may serve as a potential target for the diagnosis of RPL.


Asunto(s)
MicroARNs , Preeclampsia , ARN Largo no Codificante , Femenino , Embarazo , Humanos , Trofoblastos/metabolismo , Proliferación Celular/genética , Sistema de Señalización de MAP Quinasas , Preeclampsia/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Movimiento Celular/genética , MicroARNs/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo K/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo
17.
Nat Immunol ; 12(10): 966-74, 2011 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-21892173

RESUMEN

Natural killer T cells (NKT cells) recognize glycolipid antigens presented by CD1d. These cells express an evolutionarily conserved, invariant T cell antigen receptor (TCR), but the forces that drive TCR conservation have remained uncertain. Here we show that NKT cells recognized diacylglycerol-containing glycolipids from Streptococcus pneumoniae, the leading cause of community-acquired pneumonia, and group B Streptococcus, which causes neonatal sepsis and meningitis. Furthermore, CD1d-dependent responses by NKT cells were required for activation and host protection. The glycolipid response was dependent on vaccenic acid, which is present in low concentrations in mammalian cells. Our results show how microbial lipids position the sugar for recognition by the invariant TCR and, most notably, extend the range of microbes recognized by this conserved TCR to several clinically important bacteria.


Asunto(s)
Glucolípidos/inmunología , Bacterias Grampositivas/inmunología , Células T Asesinas Naturales/inmunología , Animales , Antígenos CD1d/química , Antígenos CD1d/fisiología , Línea Celular , Glucolípidos/química , Humanos , Interferón gamma/biosíntesis , Ratones , Ratones Endogámicos C57BL , Receptores de Antígenos de Linfocitos T/metabolismo
18.
Cardiovasc Diabetol ; 22(1): 90, 2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37076850

RESUMEN

BACKGROUND: The triglyceride-glucose (TyG) index, a simple measure of insulin resistance, is associated with intracranial atherosclerosis (ICAS) and stroke. In hypertensive populations, this association may be pronounced. The aim was to investigate the relationship between TyG and symptomatic intracranial atherosclerosis (sICAS) and recurrence risk in ischemic stroke patients with hypertension. METHODS: This prospective, multicenter cohort study included patients with acute minor ischemic stroke with a preadmission diagnosis of hypertension from September 2019 to November 2021 with a 3-month follow-up. The presence of sICAS was determined by a combination of clinical manifestations, the location of the infarction, and the corresponding artery with moderate-to-severe stenosis. ICAS burden was determined by the degree and number of ICAS occurrences. Fasting blood glucose (FBG) and triglyceride (TG) were measured to calculate TyG. The main outcome was ischemic stroke recurrence during the 90-day follow-up. Multivariate regression models were used to explore the association of TyG, sICAS, and ICAS burden with stroke recurrence. RESULTS: There were 1281 patients with a mean age of 61.6 ± 11.6 years; 70.1% were male, and 26.4% were diagnosed with sICAS. There were 117 patients who experienced stroke recurrence during follow-up. Patients were categorized according to quartiles of TyG. After adjusting for confounders, the risk of sICAS was greater (OR 1.59, 95% CI 1.04-2.43, p = 0.033) and the risk of stroke recurrence was significantly higher (HR 2.02, 95% CI 1.07-3.84, p = 0.025) in the fourth TyG quartile than in the first quartile. The restricted cubic spline (RCS) plot revealed a linear relationship between TyG and sICAS, and the threshold value for TyG was 8.4. Patients were then dichotomized into low and high TyG groups by the threshold. Patients with high TyG combined with sICAS had a higher risk of recurrence (HR 2.54, 95% CI 1.39-4.65) than patients with low TyG without sICAS. An interaction effect on stroke recurrence between TyG and sICAS was found (p = 0.043). CONCLUSION: TyG is a significant risk factor for sICAS in hypertensive patients, and there is a synergistic effect of sICAS and higher TyG on ischemic stroke recurrence. TRIAL REGISTRATION NUMBER: The study was registered on 16 August 2019 at https://www.chictr.org.cn/showprojen.aspx?proj=41160 (No. ChiCTR1900025214).


Asunto(s)
Hipertensión , Arteriosclerosis Intracraneal , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Estudios de Cohortes , Constricción Patológica , Estudios Prospectivos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Arterias , Hipertensión/diagnóstico , Hipertensión/epidemiología , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/epidemiología , Factores de Riesgo , Glucosa , Arteriosclerosis Intracraneal/diagnóstico por imagen , Arteriosclerosis Intracraneal/epidemiología , Triglicéridos , Glucemia , Biomarcadores
19.
Opt Lett ; 48(7): 1874-1877, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37221788

RESUMEN

We propose and demonstrate deformed square cavity microlasers for realizing highly efficient output from a connected waveguide. The square cavities are deformed asymmetrically by replacing two adjacent flat sides with circular arcs to manipulate the ray dynamics and couple the light to the connected waveguide. The numerical simulations show that the resonant light can efficiently couple to the fundamental mode of the multi-mode waveguide by carefully designing the deformation parameter utilizing global chaos ray dynamics and internal mode coupling. An enhancement of approximately six times in the output power is realized in the experiment compared to the non-deformed square cavity microlasers, while the lasing thresholds are reduced by about 20%. The measured far-field pattern shows highly unidirectional emission agreeing well with the simulation, which confirms the feasibility of the deformed square cavity microlasers for practical applications.

20.
Eur Radiol ; 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37932390

RESUMEN

OBJECTIVE: To investigate the potential applicability of AI-assisted compressed sensing (ACS) in knee MRI to enhance and optimize the scanning process. METHODS: Volunteers and patients with sports-related injuries underwent prospective MRI scans with a range of acceleration techniques. The volunteers were subjected to varied ACS acceleration levels to ascertain the most effective level. Patients underwent scans at the determined optimal 3D-ACS acceleration level, and 3D compressed sensing (CS) and 2D parallel acquisition technology (PAT) scans were performed. The resultant 3D-ACS images underwent 3.5 mm/2.0 mm multiplanar reconstruction (MPR). Experienced radiologists evaluated and compared the quality of images obtained by 3D-ACS-MRI and 3D-CS-MRI, 3.5 mm/2.0 mm MPR and 2D-PAT-MRI, diagnosed diseases, and compared the results with the arthroscopic findings. The diagnostic agreement was evaluated using Cohen's kappa correlation coefficient, and both absolute and relative evaluation methods were utilized for objective assessment. RESULTS: The study involved 15 volunteers and 53 patients. An acceleration factor of 10.69 × was identified as optimal. The quality evaluation showed that 3D-ACS provided poorer bone structure visualization, and improved cartilage visualization and less satisfactory axial images with 3.5 mm/2.0 mm MPR than 2D-PAT. In terms of objective evaluation, the relative evaluation yielded satisfactory results across different groups, while the absolute evaluation revealed significant variances in most features. Nevertheless, high levels of diagnostic agreement (κ: 0.81-0.94) and accuracy (0.83-0.98) were observed across all diagnoses. CONCLUSION: ACS technology presents significant potential as a replacement for traditional CS in 3D-MRI knee scans, allowing thinner MPRs and markedly faster scans without sacrificing diagnostic accuracy. CLINICAL RELEVANCE STATEMENT: 3D-ACS-MRI of the knee can be completed in the 160 s with good diagnostic consistency and image quality. 3D-MRI-MPR can replace 2D-MRI and reconstruct images with thinner slices, which helps to optimize the current MRI examination process and shorten scanning time. KEY POINTS: • AI-assisted compressed sensing technology can reduce knee MRI scan time by over 50%. • 3D AI-assisted compressed sensing MRI and related multiplanar reconstruction can replace traditional accelerated MRI and yield thinner 2D multiplanar reconstructions. • Successful application of 3D AI-assisted compressed sensing MRI can help optimize the current knee MRI process.

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