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1.
Cereb Cortex ; 34(5)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38771245

RESUMEN

Arterial spin-labeled perfusion and blood oxygenation level-dependent functional MRI are indispensable tools for noninvasive human brain imaging in clinical and cognitive neuroscience, yet concerns persist regarding the reliability and reproducibility of functional MRI findings. The circadian rhythm is known to play a significant role in physiological and psychological responses, leading to variability in brain function at different times of the day. Despite this, test-retest reliability of brain function across different times of the day remains poorly understood. This study examined the test-retest reliability of six repeated cerebral blood flow measurements using arterial spin-labeled perfusion imaging both at resting-state and during the psychomotor vigilance test, as well as task-induced cerebral blood flow changes in a cohort of 38 healthy participants over a full day. The results demonstrated excellent test-retest reliability for absolute cerebral blood flow measurements at rest and during the psychomotor vigilance test throughout the day. However, task-induced cerebral blood flow changes exhibited poor reliability across various brain regions and networks. Furthermore, reliability declined over longer time intervals within the day, particularly during nighttime scans compared to daytime scans. These findings highlight the superior reliability of absolute cerebral blood flow compared to task-induced cerebral blood flow changes and emphasize the importance of controlling time-of-day effects to enhance the reliability and reproducibility of future brain imaging studies.


Asunto(s)
Encéfalo , Circulación Cerebrovascular , Imagen por Resonancia Magnética , Descanso , Humanos , Masculino , Femenino , Adulto , Circulación Cerebrovascular/fisiología , Reproducibilidad de los Resultados , Descanso/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Encéfalo/irrigación sanguínea , Adulto Joven , Imagen por Resonancia Magnética/métodos , Imagen de Perfusión/métodos , Desempeño Psicomotor/fisiología , Ritmo Circadiano/fisiología , Nivel de Alerta/fisiología
2.
Stroke ; 55(7): 1838-1846, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38818733

RESUMEN

BACKGROUND: Previous studies yielded conflicting results about the influence of blood pressure (BP) and antihypertensive treatment on cerebral small vessel disease. Here, we conducted a Mendelian randomization study to investigate the effect of BP and antihypertensive drugs on cerebral small vessel disease. METHODS: We extracted single-nucleotide polymorphisms for systolic BP and diastolic BP from a genome-wide association study (N=757 601) and screened single-nucleotide polymorphisms associated with calcium channel blockers, thiazides, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and ß-blockers from public resources as instrumental variables. Then, we chose the genome-wide association study of white matter hyperintensity (WMH; N=18 381), cerebral microbleed (3556 cases, 22 306 controls), white matter perivascular space (9317 cases, 29 281 controls), basal ganglia perivascular space (BGPVS; 8950 cases, 29 953 controls), hippocampal perivascular space (HIPPVS; 9163 cases, 29 708 controls), and lacunar stroke (6030 cases, 248 929 controls) as outcome data sets. Subsequently, we conducted a 2-sample Mendelian randomization analysis. RESULTS: We found that elevated systolic BP significantly increases the risk of BGPVS (odds ratio [OR], 1.05 [95% CI, 1.04-1.07]; P=1.72×10-12), HIPPVS (OR, 1.04 [95% CI, 1.02-1.05]; P=2.71×10-7), and lacunar stroke (OR, 1.41 [95% CI, 1.30-1.54]; P=4.97×10-15). There was suggestive evidence indicating that elevated systolic BP is associated with higher WMH volume (ß=0.061 [95% CI, 0.018-0.105]; P=5.58×10-3) and leads to an increased risk of cerebral microbleed (OR, 1.16 [95% CI, 1.04-1.29]; P=7.17×10-3). Elevated diastolic BP was significantly associated with higher WMH volume (ß=0.087 [95% CI, 0.049-0.124]; P=5.23×10-6) and significantly increased the risk of BGPVS (OR, 1.05 [95% CI, 1.04-1.06]; P=1.20×10-16), HIPPVS (OR, 1.03 [95% CI, 1.02-1.04]; P=2.96×10-6), and lacunar stroke (OR, 1.31 [95% CI, 1.21-1.41]; P=2.67×10-12). The use of calcium channel blocker to lower BP was significantly associated with lower WMH volume (ß=-0.287 [95% CI, -0.408 to -0.165]; P=4.05×10-6) and significantly reduced the risk of BGPVS (OR, 0.85 [95% CI, 0.81-0.89]; P=8.41×10-19) and HIPPVS (OR, 0.88 [95% CI, 0.85-0.92]; P=6.72×10-9). CONCLUSIONS: Our findings contribute to a better understanding of the pathogenesis of cerebral small vessel disease. Additionally, the utilization of calcium channel blockers to decrease BP can effectively reduce the likelihood of WMH, BGPVS, and HIPPVS. These findings offer valuable insights for the management and prevention of cerebral small vessel disease.


Asunto(s)
Antihipertensivos , Presión Sanguínea , Enfermedades de los Pequeños Vasos Cerebrales , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Humanos , Enfermedades de los Pequeños Vasos Cerebrales/genética , Enfermedades de los Pequeños Vasos Cerebrales/tratamiento farmacológico , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/genética , Hipertensión/tratamiento farmacológico , Hipertensión/genética , Femenino , Masculino , Accidente Vascular Cerebral Lacunar/genética , Accidente Vascular Cerebral Lacunar/tratamiento farmacológico , Bloqueadores de los Canales de Calcio/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Persona de Mediana Edad
3.
BMC Genomics ; 25(1): 65, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38229017

RESUMEN

BACKGROUND: Pod shell thickness (PST) is an important agronomic trait of peanut because it affects the ability of shells to resist pest infestations and pathogen attacks, while also influencing the peanut shelling process. However, very few studies have explored the genetic basis of PST. RESULTS: An F2 segregating population derived from a cross between the thick-shelled cultivar Yueyou 18 (YY18) and the thin-shelled cultivar Weihua 8 (WH8) was used to identify the quantitative trait loci (QTLs) for PST. On the basis of a bulked segregant analysis sequencing (BSA-seq), four QTLs were preliminarily mapped to chromosomes 3, 8, 13, and 18. Using the genome resequencing data of YY18 and WH8, 22 kompetitive allele-specific PCR (KASP) markers were designed for the genotyping of the F2 population. Two major QTLs (qPSTA08 and qPSTA18) were identified and finely mapped, with qPSTA08 detected on chromosome 8 (0.69-Mb physical genomic region) and qPSTA18 detected on chromosome 18 (0.15-Mb physical genomic region). Moreover, qPSTA08 and qPSTA18 explained 31.1-32.3% and 16.7-16.8% of the phenotypic variation, respectively. Fifteen genes were detected in the two candidate regions, including three genes with nonsynonymous mutations in the exon region. Two molecular markers (Tif2_A08_31713024 and Tif2_A18_7198124) that were developed for the two major QTL regions effectively distinguished between thick-shelled and thin-shelled materials. Subsequently, the two markers were validated in four F2:3 lines selected. CONCLUSIONS: The QTLs identified and molecular markers developed in this study may lay the foundation for breeding cultivars with a shell thickness suitable for mechanized peanut shelling.


Asunto(s)
Arachis , Sitios de Carácter Cuantitativo , Arachis/genética , Mapeo Cromosómico , Fitomejoramiento , Fenotipo
4.
J Am Chem Soc ; 146(22): 15446-15452, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38776639

RESUMEN

Linker installation is a potent strategy for integrating specific properties and functionalities into metal-organic frameworks (MOFs). This method enhances the structural diversity of frameworks and enables the precise construction of robust structures, complementing the conventional postsynthetic modification approaches, by fully leveraging open metal sites and active organic linkers at targeting locations. Herein, we demonstrated an insertion of a d-camphorate linker into a flexible Zr-based MOF, PCN-700, through linker installation. The resultant homochiral MOF not only exhibits remarkable stability but also functions as a highly efficient luminescent material for enantioselective sensing. Competitive absorption and energy/electron transfer processes contribute to the sensing performance, while the difference in binding affinities dominates the enantioselectivity. This work presents a straightforward route to crafting stable homochiral MOFs for enantioselective sensing.

5.
Cancer Immunol Immunother ; 73(8): 159, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850359

RESUMEN

BACKGROUND: Although, immune checkpoint inhibitors (ICIs) have been widely applied in the therapy of malignant tumors, the efficacy and safety of ICIs in patients with tumors and pre-existing CAD, especially chronic coronary syndromes (CCS) or their risk factors (CRF), is not well identified. METHODS: This was a nationwide multicenter observational study that enrolled participants who diagnosed with solid tumors and received ICIs therapy. The main efficacy indicators were progression-free survival (PFS) and overall survival (OS), followed by objective response rate (ORR) and disease control rate (DCR). Safety was assessed by describing treatment-related adverse events (TRAEs) during ICIs therapy evaluated by the Common Terminology Criteria for Adverse Events 5.0 (CTCAE 5.0). RESULTS: In the current research, we retrospectively analyzed the data of 551 patients diagnosed with solid tumors and received ICIs therapy, and these patients were divided into CCS/CRF group and non-CCS/CRF group. Patients with CCS/CRF had more favorable PFS and OS than patients without CCS/CRF (P < 0.001) and the pre-existing CCS/CRF was a protective factor for survival. The ORR (51.8% vs. 39.1%) and DCR (95.8% vs. 89.2%) were higher in CCS/CRF group than in non-CCS/CRF group (P = 0.003, P = 0.006). In this study, there was no significant difference in treatment-related adverse events (TRAEs), including immune-related adverse events (irAEs), between the two groups. CONCLUSIONS: We concluded that ICIs appear to have better efficacy in malignant solid tumor patients with pre-existing CCS/CRF and are not accompanied by more serious irAEs.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico , Neoplasias , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Femenino , Masculino , Neoplasias/tratamiento farmacológico , Neoplasias/complicaciones , Neoplasias/inmunología , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Factores de Riesgo , Adulto , Anciano de 80 o más Años , Estudios de Cohortes
6.
BMC Plant Biol ; 24(1): 718, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39069623

RESUMEN

BACKGROUND: Powdery mildew (caused by Blumeria graminis f. sp. tritici (Bgt)) and leaf rust (caused by Puccinia triticina (Pt)) are prevalent diseases in wheat (Triticum aestivum L.) production. Thinopyrum ponticum (2n = 10x = 70, EeEeEbEbExExStStStSt) contains genes that confer high levels of resistance to these diseases. RESULTS: An elite wheat-Th. ponticum disomic substitution line, DS5Ag(5D), was developed in the Bainong Aikang 58 (AK58) background. The line was assessed using genomic in situ hybridization (GISH), oligo-nucleotide probe multiplex (ONPM) fluorescence in situ hybridization (FISH), and molecular markers. Twenty eight chromosome-specific molecular markers were identified for the alien chromosome, and 22 of them were co-dominant. Additionally, SNP markers from the wheat 660 K SNP chip were utilized to confirm chromosome identification and they provide molecular tools for tagging the chromosome in concern. The substitution line demonstrated high levels of resistance to powdery mildew throughout its growth period and to leaf rust at the adult stage. Based on the resistance evaluation of five F5 populations between the substitution lines and wheat genotypes with different levels of sensitivity to the two diseases. Results showed that the resistance genes located on 5Ag confered stable resistance against both diseases across different backgrounds. Resistance spectrum analysis combined with diagnostic marker detection of known resistance genes of Th. ponticum revealed that 5Ag contained two novel genes, Pm5Ag and Lr5Ag, which conferred resistance to powdery mildew and leaf rust, respectively. CONCLUSIONS: In this study, a novel wheat-Th. ponticum disomic substitution line DS5Ag(5D) was successfully developed. The Th. ponticum chromosome 5Ag contain new resistance genes for powdery mildew and leaf rust. Chromosomic-specific molecular markers were generated and they can be used to track the 5Ag chromosome fragments. Consequently, this study provides new elite germplasm resources and molecular markers to facilitate the breeding of wheat varieties that is resistant to powdery mildew and leaf rust.


Asunto(s)
Ascomicetos , Basidiomycota , Resistencia a la Enfermedad , Enfermedades de las Plantas , Puccinia , Triticum , Triticum/genética , Triticum/microbiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Ascomicetos/fisiología , Basidiomycota/fisiología , Puccinia/fisiología , Genes de Plantas , Cromosomas de las Plantas/genética , Poaceae/genética , Poaceae/microbiología , Polimorfismo de Nucleótido Simple , Marcadores Genéticos , Fitomejoramiento
7.
Small ; : e2402423, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38845523

RESUMEN

Electromagnetic protection in extreme environments requires materials with excellent thermal insulation capability and mechanical property to withstand severe temperature fluctuations and complex external stresses. Achieving strong electromagnetic wave absorption (EMA) while sustaining these exceptional properties remains a significant challenge. Herein, a facile approach is demonstrated to fabricate a biomimetic leaf-vein MXene/CNTs/PI (MCP) aerogel with parallel venations through bidirectional freeze-casting method. Due to its multi-arch lamellar structure and parallel venations within the aerogel layers, the ultralight MCP aerogel (16.9 mg·cm-3) achieves a minimum reflection loss (RLmin) of -75.8 dB and a maximum effective absorption bandwidth (EABmax) of 7.14 GHz with an absorber content of only 2.4 wt%, which also exhibits superelasticity and structural stability over a wide temperature range from -196 to 400 °C. Moreover, this unique structure facilitates rapid heat dissipation within the layers, while significantly impeding heat transfer between adjacent layers, achieving an ultralow thermal conductivity of 15.3 mW·m-1·K-1 for thermal superinsulation. The combination of excellent EMA performance, robust structural stability, and thermal superinsulation provides a potential design scheme under extreme conditions, especially in aerospace applications.

8.
J Transl Med ; 22(1): 818, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227968

RESUMEN

BACKGROUND: Dengue virus (DENV) is the most widespread arbovirus. The World Health Organization (WHO) declared dengue one of the top 10 global health threats in 2019. However, it has been underrepresented in bibliometric analyses. This study employs bibliometric analysis to identify research hotspots and trends, offering a comprehensive overview of the current research dynamics in this field. RESULTS: We present a report spanning from 1995 to 2023 that provides a unique longitudinal analysis of Dengue virus (DENV) research, revealing significant trends and shifts not extensively covered in previous literature. A total of 10,767 DENV-related documents were considered, with a notable increase in publications, peaking at 747 articles in 2021. Plos Neglected Tropical Diseases has become the leading journal in Dengue virus research, publishing 791 articles in this field-the highest number recorded. Our bibliometric analysis provides a comprehensive mapping of DENV research across multiple dimensions, including vector ecology, virology, and emerging therapies. The study delineates a complex network of immune response genes, including IFNA1, DDX58, IFNB1, STAT1, IRF3, and NFKB1, highlighting significant trends and emerging themes, particularly the impacts of climate change and new outbreaks on disease transmission. Our findings detail the progress and current status of key vaccine candidates, including the licensed Dengvaxia, newer vaccines such as Qdenga and TV003, and updated clinical trials. The study underscores significant advancements in antiviral therapies and vector control strategies for dengue, highlighting innovative drug candidates such as AT-752 and JNJ-1802, and the potential of drug repurposing with agents like Ribavirin, Remdesivir, and Lopinavir. Additionally, it discusses biological control methods, including the introduction of Wolbachia-infected mosquitoes and gene-editing technologies. CONCLUSION: This bibliometric study underscores the critical role of interdisciplinary collaboration in advancing DENV research, identifying key trends and areas needing further exploration, including host-virus dynamics, the development and application of antiviral drugs and vaccines, and the use of artificial intelligence. It advocates for strengthened partnerships across various disciplines to effectively tackle the challenges posed by DENV.


Asunto(s)
Bibliometría , Virus del Dengue , Humanos , Dengue/epidemiología , Dengue/virología , Animales , Investigación Biomédica/tendencias , Historia del Siglo XXI , Historia del Siglo XX
9.
IUBMB Life ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38838376

RESUMEN

Multiple sclerosis (MS) is a common autoimmune illness that is difficult to treat. The upregulation of Th17 cells is critical in the pathological process of MS. Hederagenol (Hed) has been shown to lower IL-17 levels, although its role in MS pathophysiology is uncertain. In this study, we explore whether Hed could ameliorate MS by modulating Th17 cell differentiation, with the goal of identifying new treatment targets for MS. The experimental autoimmune encephalomyelitis (EAE) mouse model was conducted and Hed was intraperitoneally injected into mice. The weight was recorded and the clinical symptom grade was assessed. Hematoxylin-eosin staining was carried out to determine the extent of inflammation in the spinal cord and liver. The luxol Fast Blue staining was performed to detect the pathological changes in the myelin sheath. Nerve damage was detected using NeuN immunofluorescence staining and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. Immunohistology approaches were used to study alterations in immune cells in the spinal cord. The proportions of T cell subsets in the spleens were analyzed by flow cytometry. RORγt levels were measured using quantitative real-time PCR or Western blot. The activity of the RORγt promoter was analyzed by Chromatin immunoprecipitation. Hed administration reduced the clinical symptom grade of EAE mice, as well as the inflammatory infiltration, demyelination, and cell disorder of the spinal cord, while having no discernible effect on the mouse weight. In addition, Hed treatment significantly reduced the number of T cells, particularly Th17 cells in the spinal cord and spleen-isolated CD4+ T cells. Hed lowered the RORγt levels in spleens and CD4+ T cells and overexpression of RORγt reversed the inhibitory effect of Hed on Th17 differentiation. Hed decreased nerve injury by modulating Th17 differentiation through the RORγt promoter. Hed regulates Th17 differentiation by reducing RORγt promoter activity, which reduces nerve injury and alleviates EAE.

10.
J Hum Genet ; 69(7): 311-319, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38528048

RESUMEN

Our study aimed to investigate the association between the transition of the TXNIP gene methylation level and the risk of incident type 2 diabetes mellitus (T2DM). This study included 263 incident cases of T2DM and 263 matched non-T2DM participants. According to the methylation levels of five loci (CpG1-5; chr1:145441102-145442001) on the TXNIP gene, the participants were classified into four transition groups: maintained low, low to high, high to low, and maintained high methylation levels. Compared with individuals whose methylation level of CpG2-5 at the TXNIP gene was maintained low, individuals with maintained high methylation levels showed a 61-87% reduction in T2DM risk (66% for CpG2 [OR: 0.34, 95% CI: 0.14, 0.80]; 77% for CpG3 [OR: 0.23, 95% CI: 0.07, 0.78]; 87% for CpG4 [OR: 0.13, 95% CI: 0.03, 0.56]; and 61% for CpG5 [OR: 0.39, 95% CI: 0.16, 0.92]). Maintained high methylation levels of four loci of the TXNIP gene are associated with a reduction of T2DM incident risk in the current study. Our study suggests that preserving hypermethylation levels of the TXNIP gene may hold promise as a potential preventive measure against the onset of T2DM.


Asunto(s)
Proteínas Portadoras , Islas de CpG , Metilación de ADN , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/epidemiología , Metilación de ADN/genética , Masculino , Proteínas Portadoras/genética , Femenino , Estudios de Casos y Controles , Persona de Mediana Edad , Anciano , Predisposición Genética a la Enfermedad , Factores de Riesgo , Adulto
11.
Opt Lett ; 49(1): 145-148, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134173

RESUMEN

Yb-doped sesquioxides represent one of the most excellent laser crystals applying for high-power ultrafast lasers owing to their very high thermal conductivities and broadband emission spectra. Pumped by a high-brightness Yb-fiber laser at 976 nm, the Yb:Lu2O3 laser delivers a maximum output power that amounts to 3.55 W in the continuous-wave regime with an optical efficiency of 75%. In the mode-locked regime, 90-fs pulses were generated via soft-aperture Kerr-lens mode-locking at 1080.6 nm with an average output power of 2.85 W, which corresponds to an optical efficiency of 60.3% and a slope efficiency of 68.8%. Average output power of the mode-locked Yb:Lu2O3 laser can be further scaled to 3.05 W at the expense of the pulse duration (178 fs), which corresponds to an optical efficiency as high as 64.5%. To the best of our knowledge, it is the highest optical efficiency ever reported from any solid-state Kerr-lens mode-locked Yb lasers.

12.
Chemistry ; 30(42): e202401276, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38802325

RESUMEN

Hydrogen-bonded frameworks have garnered significant attention due to their flexible structures with tailored porosity, making them a promising class of porous framework materials. However, the direct synthesis of hydrogen-bonded frameworks with specific functions is highly challenging due to the unpredictable formation of hydrogen-bonded frameworks. In response, postsynthetic modification has emerged as a potent strategy to imbue desired functions into hydrogen-bonded frameworks. Recent advances have demonstrated the effectiveness of postsynthetic modification in hydrogen-bonded frameworks for studying their mechanical, luminescent, electrochemical, and chiral properties. In this concept, we comprehensively summarize the methodologies and outcomes of postsynthetic modification to hydrogen-bonded frameworks, providing a highlight of this exciting research area.

13.
Exp Eye Res ; 246: 110014, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39074653

RESUMEN

In this study, we investigated the effects of flickering light on refractive development of mice and the changes of fundus structure and function during this process. C57BL/6 mice were randomly divided into control group and flickering light-induced myopia (FLM) group. Mice in the control group were fed under normal lighting. FLM group mice were fed under lighting with a duty cycle of 50% and flash frequency of 2 Hz. Refractive status, axial length (AL), corneal radius of curvature (CRC), and electroretinogram signals were measured in all animals before treatment and at 2 and 4 weeks after treatment. Retinal thickness (RT), choroidal thickness (ChT) and choroidal blood perfusion (ChBP) were measured by optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). After 4 weeks of flickering light stimulation, the mice became myopia, the AL increased, but the CRC remained constant. The induction of myopia reduced the implicit time and amplitude of a-wave and b-wave in electroretinogram, which affects the function of retina. Full-layer retinal thickness, ChT and ChBP decreased at both 2 and 4 weeks after flickering light induction. The superficial and middle layers of the retina were significantly thinner, while the deep layer was only slightly thinner without statistical significance. Calculated by the concentric circle algorithm, the decrease of choroidal blood perfusion in FLM was mainly concentrated in the concentric circle area with the optic disc as the center radius of 150-450 µm. In conclusion, the present study shows that flickering light can successfully induce myopia in C57BL/6 mice, affect the electrophysiological activity of retina, and cause changes in fundus tissue structure and blood flow.


Asunto(s)
Modelos Animales de Enfermedad , Electrorretinografía , Angiografía con Fluoresceína , Fondo de Ojo , Ratones Endogámicos C57BL , Miopía , Refracción Ocular , Retina , Tomografía de Coherencia Óptica , Animales , Ratones , Tomografía de Coherencia Óptica/métodos , Miopía/fisiopatología , Miopía/etiología , Refracción Ocular/fisiología , Retina/fisiopatología , Angiografía con Fluoresceína/métodos , Coroides/irrigación sanguínea , Estimulación Luminosa , Luz , Longitud Axial del Ojo , Masculino
14.
Chemphyschem ; : e202400396, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889310

RESUMEN

The pursuit of molecule-based magnetic memory materials contributes significantly to high-density information storage research in the frame of the ongoing information technologies revolution. Remarkable progress has been achieved in both transition metal (TM) and lanthanide based single-molecule magnets (SMMs). Notably, six-coordinated CoII SMMs hold particular research significance owing to the economic and abundant nature of 3d TM ions compared to lanthanide ions, the substantial spin-orbit coupling of CoII ions, the potential for precise control over coordination geometry, and the air-stability of coordination-saturated structures. In this review, we will summarize the progress made in six-coordinated CoII SMMs, organized by their coordination geometry and molecular structure similarity. Valuable insights, principles, and new mechanism gleaned from this research and remaining issues that need to be addressed will also be discussed to guide future optimization.

15.
Chemphyschem ; 25(16): e202400143, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-38726743

RESUMEN

Electrocatalytic nitrogen reduction reaction (NRR) is a green and highly efficient way to replace the industrial Haber-Bosch process. Herein, clusters consisting of three transition metal atoms loaded on C2N as NRR electrocatalysts are investigated using density functional theory (DFT). Meanwhile, Ca was introduced as a promoter and the role of Ca in NRR was investigated. It was found that Ca anchored to the catalyst can act as an electron donor and effectively promote the activation of N2 on M3. In both M3@C2N and M3Ca@C2N (M=Fe, Co, Ni), the limiting potential (UL) is less negative than that of the Ru(0001) surface and has the ability to suppress the competitive hydrogen evolution reaction (HER). Among them, Fe3@C2N is suggested to be the most promising candidate for NRR with high thermal stability, strong N2 adsorption ability, low limiting potential, and good NRR selectivity. The concepts of trimetallic sites and alkaline earth metal promoters in this work provide theoretical guidance for the rational design of atomically active sites in electrocatalytic NRR.

16.
Langmuir ; 40(12): 6587-6594, 2024 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-38486393

RESUMEN

The coupling between different vibrational modes in proteins is essential for chemical dynamics and biological functions and is linked to the propagation of conformational changes and pathways of allosteric communication. However, little is known about the influence of intermolecular protein-H2O coupling on the vibrational coupling between amide A (NH) and amide I (C═O) bands. Here, we investigate the NH/CO coupling strength in various peptides with different secondary structures at the lipid cell membrane/H2O interface using femtosecond time-resolved sum frequency generation vibrational spectroscopy (SFG-VS) in which a femtosecond infrared pump is used to excite the amide A band, and SFG-VS is used to probe transient spectral evolution in the amide A and amide I bands. Our results reveal that the NH/CO coupling strength strongly depends on the bandwidth of the amide I mode and the coupling of proteins with water molecules. A large extent of protein-water coupling significantly reduces the delocalization of the amide I mode along the peptide chain and impedes the NH/CO coupling strength. A large NH/CO coupling strength is found to show a strong correlation with the high energy transfer rate found in the light-harvesting proteins of green sulfur bacteria, which may understand the mechanism of energy transfer through a molecular system and assist in controlling vibrational energy transfer by engineering the molecular structures to achieve high energy transfer efficiency.


Asunto(s)
Amidas , Agua , Amidas/química , Agua/química , Espectrofotometría Infrarroja/métodos , Proteínas/química , Péptidos/química , Vibración
17.
Protein Expr Purif ; 224: 106577, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39153562

RESUMEN

Developing more effective bioactive ingredients of natural origin is imperative for promoting wound healing. Sea cucumbers have long enjoyed a good reputation as both food delicacies and traditional medicines. In this study, we heterogeneously expressed a Apostichopus japonicus derived novel protein AjPSPLP-3, which exhibits a theoretical molecular weight of 13.034 kDa, through fusion with maltose binding protein (MBP). AjPSPLP-3 contains a strict CXXCXC motif, nine extremely conserved cysteine residues and two highly conserved cysteine residues. The predicted structure of AjPSPLP-3 consists of random coil and nine ß-sheets, Cys30-Cys67, Cys38-Cys58, Cys53-Cys90, Cys56-Cys66, and Cys81-Cys102 participating in the formation of five pairs of disulfide bonds. In vitro experiments conducted on HaCaT cells proved that AjPSPLP-3 and MBP-fused AjPSPLP-3 significantly contribute to HaCaT cells proliferation and migration without exhibiting hemolytic activity on murine erythrocytes. Specifically, treatment with 10 µmol/L MBP-fused AjPSPLP-3 protein increased the viability of HaCaT cells by 12.28 % (p < 0.001), while treatment with 10 µmol/L AjPSPLP-3 protein increased viability of HaCaT cells by 6.01 % (p < 0.01). Furthermore, wound closure of MBP-fused AjPSPLP-3 and AjPSPLP-3 were 22.51 % (p < 0.01) and 7.32 % (p < 0.05) higher than that of the control groups in HaCaT cells following 24 h of incubation.


Asunto(s)
Movimiento Celular , Proliferación Celular , Stichopus , Animales , Stichopus/genética , Stichopus/química , Proliferación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Humanos , Ratones , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/farmacología , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/aislamiento & purificación , Clonación Molecular , Secuencia de Aminoácidos , Línea Celular , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Unión a Maltosa/genética , Proteínas de Unión a Maltosa/química , Proteínas de Unión a Maltosa/metabolismo , Células HaCaT
18.
Int Microbiol ; 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39316254

RESUMEN

Antimicrobial peptides (AMPs) are a family of short defense proteins that are naturally produced by all organisms and have great potential as effective substitutes for small-molecule antibiotics. The present study aims to excavate AMPs from sea cucumbers and achieve their heterologous expression in prokaryotic Escherichia coli. Using MytC as a probe, a cysteine-stabilized peptide SCAK33 with broad-spectrum antimicrobial activity was discovered from the proteome of Apostichopus japonicas. The SCAK33 showed inhibitory effects on both gram positive and gram negative bacteria with MICs of 3-28 µM, and without significant hemolysis activity in rat blood erythrocyte. Especially, it exhibited good antimicrobial activity against Bacillus megaterium, B. subtilis, and Vibrio parahaemolyticus with the MIC of 3, 7, and 7 µM, respectively. After observation by scanning electronic microscopy (SEM) and confocal laser scanning microscope (CLSM), it was found that the cell membrane of bacteria was severely damaged. Furthermore, the recombinant SCAK33 (reSCAK33) was heterologously expressed by fusion with SUMO tag in E. coli BL21(DE3), and the protein yield reached 70 mg/L. The research will supplement the existing quantity of sea cucumber AMPs and provide data support for rapid mining and biological preparation of sea cucumber AMPs.

19.
Inorg Chem ; 63(31): 14727-14735, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39052617

RESUMEN

Optimizing the electronic configuration improved the electrocatalytic performance of Ru doping. However, efficiently doping Ru and ensuring its stability in the hollow hierarchical structure posed a challenge. This work innovatively utilized the huge temperature difference between calcination and ice water (0 °C) to rapidly dope Ru atoms onto the CoNiP hierarchical spheres. Notably, the Ru-anchored hierarchical spheres enhanced the active area and internal space utilization. In addition, the addition of Ru dopant optimized the electronic structure and hydrogen evolution reaction (HER) kinetics of CoNiP. Surprisingly, Ru-CoNiP only required 250 mV to generate 1 A cm-2, which was 1.5 times that of commercial Pt/C. Moreover, its activation energy (Ea) was 24.3% lower than CoNiP, further confirming that the Ru dopant reduced the energy barrier of alkaline HER. In conclusion, this work proposed a new method for promoting the doping of trace amounts of ruthenium into hierarchical spheres through quenching.

20.
Inorg Chem ; 63(10): 4758-4769, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38408314

RESUMEN

The efficiency of nitrogen mustards (NMs), among the first chemotherapeutic agents against cancer, is limited by their monotonous mechanism of action (MoA). And tumor hypoxia is a significant obstacle in the attenuation of the chemotherapeutic efficacy. To repurpose the drug and combat hypoxia, herein, we constructed an organo-Ir(III) prodrug, IrCpNM, with the composition of a reactive oxygen species (ROS)-inducing moiety (Ir-arene fragment)-a hypoxic responsive moiety (azo linker)-a DNA-alkylating moiety (nitrogen mustard), and realized DNA damage response (DDR)-mediated autophagy for hypoxic lung cancer therapy for the first time. Prodrug IrCpNM could upregulate the level of catalase (CAT) to catalyze the decomposition of excessive H2O2 to O2 and downregulate the expression of the hypoxia-inducible factor (HIF-1α) to relieve hypoxia. Subsequently, IrCpNM initiates the quadruple synergetic actions under hypoxia, as simultaneous ROS promotion and glutathione (GSH) depletion to enhance the redox disbalance and severe oxidative and cross-linking DNA damages to trigger the occurrence of DDR-mediated autophagy via the ATM/Chk2 cascade and the PIK3CA/PI3K-AKT1-mTOR-RPS6KB1 signaling pathway. In vitro and in vivo experiments have confirmed the greatly antiproliferative capacity of IrCpNM against the hypoxic solid tumor. This work demonstrated the effectiveness of the DNA damage-responsive organometallic prodrug strategy with the microenvironment targeting system and the rebirth of traditional chemotherapeutic agents with a new anticancer mechanism.


Asunto(s)
Neoplasias Pulmonares , Profármacos , Humanos , Especies Reactivas de Oxígeno/metabolismo , Profármacos/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Peróxido de Hidrógeno , Hipoxia , Autofagia , Daño del ADN , ADN , Línea Celular Tumoral , Microambiente Tumoral
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