Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.041
Filtrar
Más filtros

País/Región como asunto
Intervalo de año de publicación
1.
Nature ; 584(7822): 579-583, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32760001

RESUMEN

New Guinea is the world's largest tropical island and has fascinated naturalists for centuries1,2. Home to some of the best-preserved ecosystems on the planet3 and to intact ecological gradients-from mangroves to tropical alpine grasslands-that are unmatched in the Asia-Pacific region4,5, it is a globally recognized centre of biological and cultural diversity6,7. So far, however, there has been no attempt to critically catalogue the entire vascular plant diversity of New Guinea. Here we present the first, to our knowledge, expert-verified checklist of the vascular plants of mainland New Guinea and surrounding islands. Our publicly available checklist includes 13,634 species (68% endemic), 1,742 genera and 264 families-suggesting that New Guinea is the most floristically diverse island in the world. Expert knowledge is essential for building checklists in the digital era: reliance on online taxonomic resources alone would have inflated species counts by 22%. Species discovery shows no sign of levelling off, and we discuss steps to accelerate botanical research in the 'Last Unknown'8.


Asunto(s)
Biodiversidad , Clasificación/métodos , Islas , Plantas/clasificación , Mapeo Geográfico , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Internet , Nueva Guinea , Especificidad de la Especie , Factores de Tiempo
2.
BMC Genomics ; 25(1): 810, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39198760

RESUMEN

BACKGROUND: The respiratory chain plays a key role in the growth of Mycobacterium tuberculosis complex (MTBC). However, the exact regulatory mechanisms of this system still need to be elucidated, and only a few studies have investigated the impact of genetic mutations within the respiratory chain on MTBC transmission. This study aims to explore the impact of respiratory chain gene mutations on the global spread of MTBC. RESULTS: A total of 13,402 isolates of MTBC were included in this study. The majority of the isolates (n = 6,382, 47.62%) belonged to lineage 4, followed by lineage 2 (n = 5,123, 38.23%). Our findings revealed significant associations between Single Nucleotide Polymorphisms (SNPs) of specific genes and transmission clusters. These SNPs include Rv0087 (hycE, G178T), Rv1307 (atpH, C650T), Rv2195 (qcrA, G181C), Rv2196 (qcrB, G1250T), Rv3145 (nuoA, C35T), Rv3149 (nuoE, G121C), Rv3150 (nuoF, G700A), Rv3151 (nuoG, A1810G), Rv3152 (nuoH, G493A), and Rv3157 (nuoM, A1243G). Furthermore, our results showed that the SNPs of atpH C73G, atpA G271C, qcrA G181C, nuoJ G115A, nuoM G772A, and nuoN G1084T were positively correlated with cross-country transmission clades and cross-regional transmission clades. CONCLUSIONS: Our study uncovered an association between mutations in respiratory chain genes and the transmission of MTBC. This important finding provides new insights for future research and will help to further explore new mechanisms of MTBC pathogenicity. By uncovering this association, we gain a more complete understanding of the processes by which MTBC increases virulence and spread, providing potential targets and strategies for preventing and treating tuberculosis.


Asunto(s)
Mutación , Mycobacterium tuberculosis , Polimorfismo de Nucleótido Simple , Tuberculosis , Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Tuberculosis/genética , Tuberculosis/transmisión , Humanos , Transporte de Electrón/genética , Proteínas Bacterianas/genética
3.
BMC Genomics ; 25(1): 249, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448842

RESUMEN

BACKGROUND: Iron plays a crucial role in the growth of Mycobacterium tuberculosis (M. tuberculosis). However, the precise regulatory mechanism governing this system requires further elucidation. Additionally, limited studies have examined the impact of gene mutations related to iron on the transmission of M. tuberculosis globally. This research aims to investigate the correlation between mutations in iron-related genes and the worldwide transmission of M. tuberculosis. RESULTS: A total of 13,532 isolates of M. tuberculosis were included in this study. Among them, 6,104 (45.11%) were identified as genomic clustered isolates, while 8,395 (62.04%) were classified as genomic clade isolates. Our results showed that a total of 12 single nucleotide polymorphisms (SNPs) showed a positive correlation with clustering, such as Rv1469 (ctpD, C758T), Rv3703c (etgB, G1122T), and Rv3743c (ctpJ, G676C). Additionally, seven SNPs, including Rv0104 (T167G, T478G), Rv0211 (pckA, A302C), Rv0283 (eccB3, C423T), Rv1436 (gap, G654T), ctpD C758T, and etgB C578A, demonstrated a positive correlation with transmission clades across different countries. Notably, our findings highlighted the positive association of Rv0104 T167G, pckA A302C, eccB3 C423T, ctpD C758T, and etgB C578A with transmission clades across diverse regions. Furthermore, our analysis identified 78 SNPs that exhibited significant associations with clade size. CONCLUSIONS: Our study reveals the link between iron-related gene SNPs and M. tuberculosis transmission, offering insights into crucial factors influencing the pathogenicity of the disease. This research holds promise for targeted strategies in prevention and treatment, advancing research and interventions in this field.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Mycobacterium tuberculosis/genética , Secuenciación Completa del Genoma , Hierro , Mutación , Tuberculosis/genética
4.
J Am Chem Soc ; 146(29): 19649-19653, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38976364

RESUMEN

The attractive electronic properties of metal-pyrazine materials─electrical conductivity, magnetic order, and strong magnetic coupling─can be tuned in a wide range depending on the metal employed, as well as its ligand-imposed redox environment. Using solvent-directed synthesis to control the dimensionality of such systems, a discrete tetranuclear chromium(III) complex, exhibiting a rare example of bridging radical pyrazine, has been prepared from chromium(II) triflate and neutral pyrazine. The strong antiferromagnetic interaction between CrIII (S = 3/2) and radical pyrazine (S = 1/2) spins, theoretically estimated at about -932 K, leads to a thermally isolated ST = 4 ground state, which remains the only populated state observable even at room temperature.

5.
J Hepatol ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38992769

RESUMEN

BACKGROUND & AIMS: The changes of HBV-specific B-cells in chronic hepatitis B (CHB) patients underwent pegylated interferon-alfa (PEG-IFNα) treatment and achieved functional cure remain unclear. We aimed to evaluate the alterations in HBV-specific B-cells during treatment and therefore explored the mechanism of functional recovery of HBsAg-specific B-cells. METHODS: We included 39 nucleos(t)ide analogues-treated CHB patients who received sequential combination therapy with PEG-IFNα and 8 treatment-naive CHB patients. HBV-specific B-cells were characterized ex vivo using fluorescent labeled HBsAg and HBcAg. The frequency, phenotype, and subsets of HBV-specific B-cells and follicular helper T cells (Tfh-cells) were detected using flow cytometry. The functionality of HBV-specific B-cells was quantified through ELISpot assays. RESULTS: During treatment, the fraction of activated memory B-cells (MBCs) among HBsAg-specific B-cells and the expression of IgG, CXCR3, and CD38 increased. Antibody-secretion capacity of HBsAg-specific B-cell was restored after treatment only in patients with a functional cure and it showed a positive correlation with serum hepatitis B surface antibody levels. The phenotype and function of HBsAg-specific B-cells differed between patients with and without functional cure. Patients with functional cure exhibited IgG+ classical MBCs and plasmablasts in HBsAg-specific B-cells. HBcAg-specific B-cells displayed both attenuated antibody secretion with reduced IgG expression and an IgM+ atypical type of MBCs after treatment, irrespective of with and without functional cure. The number of CD40L+ Tfh-cells increased after PEG-IFNα treatment and positively correlated with HBsAg-specific B-cell activation. CONCLUSIONS: After PEG-IFNα treatment, HBsAg- and HBcAg-specific B-cells exhibit various changes in antibody secretion. Their functional differences are reflected in the alterations in phenotypes and subtypes. The presence of CD40L+ Tfh-cells is associated with the active recovery of HBsAg-specific B-cells. IMPACT AND IMPLICATIONS: HBV-related complications and hepatocellular carcinoma remain the leading causes of mortality from chronic liver disease worldwide, and a cure is rarely achieved with antiviral therapies. Elucidating the immunological mechanisms underlying the functional cure of CHB patients offers a promising therapeutic strategy for viral clearance, such as therapeutic vaccine. We analyzed the alterations in HBV-specific B-cells in patients treated with PEG-IFNα and identified novel pathways for immunotherapeutic boosting of B cell immunity.

6.
Am J Physiol Gastrointest Liver Physiol ; 327(4): G485-G498, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39259911

RESUMEN

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prevalent chronic liver condition worldwide, demanding further investigation into its pathogenesis. Circular RNAs (circRNAs) are emerging as pivotal regulators in MASLD processes, yet their pathological implications in MASLD remain poorly understood. This study focused on elucidating the role of circular RNA ribonucleotide reductase subunit M2 (circRRM2) in MASLD progression. In this study, we used both in vitro and in vivo MASLD models using long-chain-free fatty acid (FFA)-treated hepatocytes and high-fat diet (HFD)-induced MASLD in mice, respectively. We determined the expression patterns of circRRM2, microRNA-142-5p (miR-142-5p), and neuregulin 1 (NRG1) in livers of MASLD-afflicted mice and MASLD hepatocytes by RT-qPCR. Dual-luciferase reporter assays verified the binding relationships among circRRM2, miR-142-5p, and NRG1. We conducted further analyses of their roles in MASLD hepatocytes and modulated circRRM2, miR-142-5p, and NRG1 expression in vitro by transfection. Our findings were validated in vivo. The results demonstrated reduced levels of circRRM2 and NRG1, along with elevated miR-142-5p expression in MASLD livers and hepatocytes. Overexpression of circRRM2 downregulated lipogenesis-related genes and decreased triglycerides accumulation in livers of MASLD mice. MiR-142-5p, which interacts with circRRM2, effectively counteracted the effects of circRRM2 in MASLD hepatocytes. Furthermore, NRG1 was identified as a miR-142-5p target, and its overexpression mitigated the regulatory impact of miR-142-5p on MASLD hepatocytes. In conclusion, circRRM2, via its role as a miR-142-5p sponge, upregulating NRG1, possibly influenced triglycerides accumulation in both in vitro and in vivo MASLD models.NEW & NOTEWORTHY CircRRM2 expression was downregulated in free fatty acid (FFA)-challenged hepatocytes and high-fat diet (HFD) fed mice. Overexpressed circular RNA ribonucleotide reductase subunit M2 (circRRM2) attenuated metabolic dysfunction-associated steatotic liver disease (MASLD) development by suppressing FFA-induced triglycerides accumulation. CircRRM2 targeted microRNA-142-5p (miR-142-5p), which served as an upstream inhibitor of neuregulin 1 (NRG1) and collaboratively regulated MASLD progression.


Asunto(s)
Dieta Alta en Grasa , Hepatocitos , MicroARNs , Neurregulina-1 , ARN Circular , Animales , MicroARNs/metabolismo , MicroARNs/genética , Ratones , Hepatocitos/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Masculino , Neurregulina-1/genética , Neurregulina-1/metabolismo , Ratones Endogámicos C57BL , Hígado Graso/metabolismo , Hígado Graso/genética , Humanos , Hígado/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Ribonucleósido Difosfato Reductasa
7.
Chem Rec ; : e202400098, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289830

RESUMEN

Industry, agriculture, and a growing population all have a major impact on the scarcity of clean-water. Desalinating or purifying contaminated water for human use is crucial. The combination of thermal membrane systems can outperform conventional desalination with the help of synergistic management of the water-energy nexus. High energy requirement for desalination is a key challenge for desalination cost and its commercial feasibility. The solution to these problems requires the intermarriage of multidisciplinary approaches such as electrochemistry, chemical, environmental, polymer, and materials science and engineering. The most feasible method for producing high-quality freshwater with a reduced carbon footprint is demanding incorporation of industrial low-grade heat with membrane distillation (MD). More precisely, by using a reverse electrodialysis (RED) setup that is integrated with MD, salinity gradient energy (SGE) may be extracted from highly salinized MD retentate. Integrating MD-RED can significantly increase energy productivity without raising costs. This review provides a comprehensive summary of the prospects, unresolved issues, and developments in this cutting-edge field. In addition, we summarize the distinct physicochemical characteristics of the membranes employed in MD and RED, together with the approaches for integrating them to facilitate effective water recovery and energy conversion from salt gradients and freshwater.

8.
Appl Opt ; 63(13): 3462-3469, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38856531

RESUMEN

The polarization effect of cube-corner reflectors (CCRs), which influences the performance of optical systems, requires comprehensive analysis. This study developed a model for the polarization state of uncoated solid and hollow CCRs using the Jones matrix derivation and Zemax software simulations. The accuracies of theoretical analyses and simulations were verified using an experimental setup. Theoretical analysis, simulation, and experimental results revealed that hollow CCRs are insensitive to the polarization state of the incident light, exhibiting average variations of 0.8° and 0.7° in the polarization direction and ellipticity, respectively. Contrastingly, the high sensitivity of solid CCRs to the polarization state of the incident light varied across different incident regions. The propagation paths 2-1-3 and 3-1-2 with minor polarization effects involved light that entered from one side of the CCR, traversed the bottom, and emitted from the other side. In these regions, the average variations in the polarization direction and ellipticity were 10.7° and 6.6°, respectively, whereas more affected regions exhibited corresponding values of 44.8° and 20.0°. These findings guide the enhancement and optimization of the performance of optical systems using CCRs.

9.
Appl Opt ; 63(5): 1438-1444, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38437325

RESUMEN

In this paper, we propose a method to suppress the speckle noise in a holographic display based on pixel processing. Through the separation of object pixels in space, the recorded object is divided into multiple object point groups. The complex amplitude of the light field for each object point group is recorded as a sub-computer-generated hologram (sub-CGH). The phase of each pixel on a sub-CGH is optimized to generate the final sub-CGH. Therefore, the pixels of the recorded object and sub-CGH are processed. In the reconstruction process, the final sub-CGHs are loaded on the spatial light modulator sequentially. The speckle noise of the reconstructed image is suppressed by reducing the algorithm error and the overlapping area of adjacent image points. The experimental results prove the feasibility of the proposed method.

10.
Sleep Breath ; 28(4): 1731-1742, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38772968

RESUMEN

PURPOSE: Major Depressive Disorder (MDD) and Insomnia Disorder (ID) are prevalent psychiatric conditions often occurring concurrently, leading to substantial impairment in daily functioning. Understanding the neurobiological underpinnings of these disorders and their comorbidity is crucial for developing effective interventions. This study aims to analyze changes in functional connectivity within attention networks and default mode networks in patients with depression and insomnia. METHODS: The functional connectivity alterations in individuals with MDD, ID, comorbid MDD and insomnia (iMDD), and healthy controls (HC) were assessed from a cohort of 174 participants. They underwent rs-fMRI scans, demographic assessments, and scale evaluations for depression and sleep quality. Functional connectivity analysis was conducted using region-of-interest (ROI) and whole-brain methods. RESULTS: The MDD and iMDD groups exhibited higher Hamilton Depression Scale (HAMD) scores compared to HC and ID groups (P < 0.001). Both ID and MDD groups displayed enhanced connectivity between the left and right orbital frontal cortex compared to HC (P < 0.05), while the iMDD group showed reduced connectivity compared to HC and ID groups (P < 0.05). In the left insula, reduced connectivity with the right medial superior frontal gyrus was observed across patient groups compared to HC (P < 0.05), with the iMDD group showing increased connectivity compared to MDD (P < 0.05). Moreover, alterations in functional connectivity between the left thalamus and left temporal pole were found in iMDD compared to HC and MDD (P < 0.05). Correlation analyses revealed associations between abnormal connectivity and symptom severity in MDD and ID groups. CONCLUSIONS: Our findings demonstrate distinct patterns of altered functional connectivity in individuals with MDD, ID, and iMDD compared to healthy controls. These findings contribute to a better understanding of the pathophysiology of depression and insomnia, which could be used as a reference for the diagnosis and treatments of these patients.


Asunto(s)
Red en Modo Predeterminado , Trastorno Depresivo Mayor , Imagen por Resonancia Magnética , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico por imagen , Masculino , Femenino , Adulto , Trastorno Depresivo Mayor/fisiopatología , Persona de Mediana Edad , Red en Modo Predeterminado/fisiopatología , Red Nerviosa/fisiopatología , Red Nerviosa/diagnóstico por imagen , Atención/fisiología , Comorbilidad , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Conectoma
11.
BMC Geriatr ; 24(1): 222, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38439017

RESUMEN

BACKGROUND: This study aimed to investigate the association of high-sensitivity C-reactive protein (hs-CRP) with incident frailty as well as its effects on pre-frailty progression and regression among middle-aged and older adults. METHODS: Based on the frailty index (FI) calculated with 41 items, 6890 eligible participants without frailty at baseline from China Health and Retirement Longitudinal Study (CHARLS) were categorized into health, pre-frailty, and frailty groups. Logistic regression models were used to estimate the longitudinal association between baseline hs-CRP and incident frailty. Furthermore, a series of genetic approaches were conducted to confirm the causal relationship between CRP and frailty, including Linkage disequilibrium score regression (LDSC), pleiotropic analysis, and Mendelian randomization (MR). Finally, we evaluated the association of hs-CRP with pre-frailty progression and regression. RESULTS: The risk of developing frailty was 1.18 times (95% CI: 1.03-1.34) higher in participants with high levels of hs-CRP at baseline than low levels of hs-CRP participants during the 3-year follow-up. MR analysis suggested that genetically determined hs-CRP was potentially positively associated with the risk of frailty (OR: 1.06, 95% CI: 1.03-1.08). Among 5241 participants with pre-frailty at baseline, we found pre-frailty participants with high levels of hs-CRP exhibit increased odds of progression to frailty (OR: 1.39, 95% CI: 1.09-1.79) and decreased odds of regression to health (OR: 0.84, 95% CI: 0.72-0.98) when compared with participants with low levels of hs-CRP. CONCLUSIONS: Our results suggest that reducing systemic inflammation is significant for developing strategies for frailty prevention and pre-frailty reversion in the middle-aged and elderly population.


Asunto(s)
Proteína C-Reactiva , Fragilidad , Anciano , Humanos , Persona de Mediana Edad , Estudios Longitudinales , Proteína C-Reactiva/genética , Fragilidad/diagnóstico , Fragilidad/epidemiología , Fragilidad/genética , Estudios de Cohortes , Inflamación
12.
BMC Public Health ; 24(1): 2424, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39243030

RESUMEN

BACKGROUND: Numerous reports indicate that both obesity and type 2 diabetes mellitus (T2DM) are factors associated with cognitive impairment (CI). The objective was to assess the relationship between abdominal obesity as measured by waist-to-hip ratio adjusted for body mass index (WHRadjBMI) and CI in middle-aged and elderly patients with T2DM. METHODS: A cross-sectional study was conducted, in which a total of 1154 patients with T2DM aged ≥ 40 years were included. WHRadjBMI was calculated based on anthropometric measurements and CI was assessed utilizing the Montreal Cognitive Assessment (MoCA). Participants were divided into CI group (n = 509) and normal cognition group (n = 645). Correlation analysis and binary logistic regression were used to explore the relationship between obesity-related indicators including WHRadjBMI, BMI as well as waist circumference (WC) and CI. Meanwhile, the predictive power of these indicators for CI was estimated by receiver operating characteristic (ROC) curves. RESULTS: WHRadjBMI was positively correlated with MoCA scores, independent of sex. The Area Under the Curve (AUC) for WHRadjBMI, BMI and WC were 0.639, 0.521 and 0.533 respectively, and WHRadjBMI had the highest predictive power for CI. Whether or not covariates were adjusted, one-SD increase in WHRadjBMI was significantly related to an increased risk of CI with an adjusted OR of 1.451 (95% CI: 1.261-1.671). After multivariate adjustment, the risk of CI increased with rising WHRadjBMI quartiles (Q4 vs. Q1 OR: 2.980, 95%CI: 2.032-4.371, P for trend < 0.001). CONCLUSIONS: Our study illustrated that higher WHRadjBMI is likely to be associated with an increased risk of CI among patients with T2DM. These findings support the detrimental effects of excess visceral fat accumulation on cognitive function in middle-aged and elderly T2DM patients.


Asunto(s)
Índice de Masa Corporal , Disfunción Cognitiva , Diabetes Mellitus Tipo 2 , Relación Cintura-Cadera , Humanos , Estudios Transversales , Diabetes Mellitus Tipo 2/complicaciones , Masculino , Femenino , Persona de Mediana Edad , Anciano , Disfunción Cognitiva/etiología , Disfunción Cognitiva/epidemiología , Obesidad Abdominal/epidemiología , Obesidad Abdominal/complicaciones , Factores de Riesgo , Adulto , China/epidemiología
13.
World J Surg Oncol ; 22(1): 51, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38336734

RESUMEN

BACKGROUND: Presurgical computed tomography (CT)-guided localization is frequently employed to reduce the thoracotomy conversion rate, while increasing the rate of successful sublobar resection of ground glass nodules (GGNs) via video-assisted thoracoscopic surgery (VATS). In this study, we compared the clinical efficacies of presurgical CT-guided hook-wire and indocyanine green (IG)-based localization of GGNs. METHODS: Between January 2018 and December 2021, we recruited 86 patients who underwent CT-guided hook-wire or IG-based GGN localization before VATS resection in our hospital, and compared the clinical efficiency and safety of both techniques. RESULTS: A total of 38 patients with 39 GGNs were included in the hook-wire group, whereas 48 patients with 50 GGNs were included in the IG group. There were no significant disparities in the baseline data between the two groups of patients. According to our investigation, the technical success rates of CT-based hook-wire- and IG-based localization procedures were 97.4% and 100%, respectively (P = 1.000). Moreover, the significantly longer localization duration (15.3 ± 6.3 min vs. 11.2 ± 5.3 min, P = 0.002) and higher visual analog scale (4.5 ± 0.6 vs. 3.0 ± 0.5, P = 0.001) were observed in the hook-wire patients, than in the IG patients. Occurrence of pneumothorax was significantly higher in hook-wire patients (27.3% vs. 6.3%, P = 0.048). Lung hemorrhage seemed higher in hook-wire patients (28.9% vs. 12.5%, P = 0.057) but did not reach statistical significance. Lastly, the technical success rates of VATS sublobar resection were 97.4% and 100% in hook-wire and IG patients, respectively (P = 1.000). CONCLUSIONS: Both hook-wire- and IG-based localization methods can effectively identified GGNs before VATS resection. Furthermore, IG-based localization resulted in fewer complications, lower pain scores, and a shorter duration of localization.


Asunto(s)
Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Nódulo Pulmonar Solitario , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Verde de Indocianina , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/cirugía , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Cirugía Torácica Asistida por Video/métodos , Pulmón , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Nódulos Pulmonares Múltiples/cirugía
14.
Proc Natl Acad Sci U S A ; 118(7)2021 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-33526596

RESUMEN

The RNA polymerase inhibitor favipiravir is currently in clinical trials as a treatment for infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), despite limited information about the molecular basis for its activity. Here we report the structure of favipiravir ribonucleoside triphosphate (favipiravir-RTP) in complex with the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) bound to a template:primer RNA duplex, determined by electron cryomicroscopy (cryoEM) to a resolution of 2.5 Å. The structure shows clear evidence for the inhibitor at the catalytic site of the enzyme, and resolves the conformation of key side chains and ions surrounding the binding pocket. Polymerase activity assays indicate that the inhibitor is weakly incorporated into the RNA primer strand, and suppresses RNA replication in the presence of natural nucleotides. The structure reveals an unusual, nonproductive binding mode of favipiravir-RTP at the catalytic site of SARS-CoV-2 RdRp, which explains its low rate of incorporation into the RNA primer strand. Together, these findings inform current and future efforts to develop polymerase inhibitors for SARS coronaviruses.


Asunto(s)
Amidas/farmacología , ARN Polimerasa Dependiente de ARN de Coronavirus/metabolismo , Inhibidores Enzimáticos/farmacología , Pirazinas/farmacología , SARS-CoV-2/ultraestructura , Amidas/química , ARN Polimerasa Dependiente de ARN de Coronavirus/antagonistas & inhibidores , ARN Polimerasa Dependiente de ARN de Coronavirus/química , Microscopía por Crioelectrón/métodos , Inhibidores Enzimáticos/química , Pirazinas/química , Ribonucleótidos/química , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/enzimología , Imagen Individual de Molécula/métodos
15.
Endocr Res ; 49(2): 92-105, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38288985

RESUMEN

Purpose:Osteoporosis is characterized by low bone mineral density (BMD) and high risk of osteoporotic fracture (OF). Peripheral blood monocytes (PBM) can differentiate into osteoclasts to resorb bone. This study was to identify PBM-expressed proteins significant for osteoporosis in Chinese Han elderly population (>65 years), and focused on two phenotypes of osteoporosis: low BMD and OF. METHODS: Label-free quantitative proteomics was employed to profile PBM proteome and to identify differentially expressed proteins (DEPs) between OF (N=27) vs. non-fractured (NF, N=24) subjects and between low BMD (N=12) vs. high BMD (N=12) subjects in women. Western blotting (WB) was conducted to validate differential expression, and ELISA to evaluate translational value for secretory protein of interest. RESULTS: We discovered 59 DEPs with fold change (FC)>1.3 (P<1×10-5), and validated the significant up-regulation of pyruvate kinase isozyme 2 (PKM2) with osteoporosis (P<0.001). PKM2 protein upregulation with OF was replicated with PBM in men (P=0.04). Plasma PKM2 protein level was significantly elevated with OF in an independent sample (N=100, FC=1.68, P=0.01). Pursuant functional assays showed that extracellular PKM2 protein supplement not only promoted monocyte trans-endothelial migration, growth, and osteoclast differentiation (marker gene expression), but also inhibited osteoblast growth, differentiation (ALP gene expression), and activity. CONCLUSION: The above findings suggest that PKM2 protein is a novel osteoporosis-associated functional protein in Chinese Han elderly population. It may serve as a risk biomarker and drug target for osteoporosis.


Asunto(s)
Densidad Ósea , Osteoporosis , Piruvato Quinasa , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Proteínas Portadoras/metabolismo , China , Pueblos del Este de Asia , Monocitos/metabolismo , Fracturas Osteoporóticas , Piruvato Quinasa/metabolismo
16.
Zhongguo Zhong Yao Za Zhi ; 49(8): 2117-2127, 2024 Apr.
Artículo en Zh | MEDLINE | ID: mdl-38812227

RESUMEN

Piperlongumine(PL), a natural alkaloid extracted from Piperis Longi Fructus, has attracted much attention in recent years because of its strong anti-tumor activity, little toxicity to normal cells, and excellent sensitizing effect combined with chemotherapy and radiotherapy, which endow PL with unique advantages as an anti-tumor drug. However, similar to other alkaloids, PL has low water solubility and poor bioavailability. To improve the application of PL in the clinical treatment of tumors, researchers have constructed various nano-drug delivery systems to increase the efficiency of PL delivery. This paper reviewed the physicochemical properties, anti-tumor mechanism, combined therapies, and nano-drug delivery systems of PL in recent years. The review aimed to provide a reference for further research on the anti-tumor effect and nano-drug delivery system of PL. Moreover, this review is expected to provide a reference for the development and application of PL in the anti-tumor therapies.


Asunto(s)
Dioxolanos , Neoplasias , Dioxolanos/química , Humanos , Animales , Neoplasias/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/administración & dosificación , Sistema de Administración de Fármacos con Nanopartículas/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/farmacología , Piperidonas
17.
Zhongguo Zhong Yao Za Zhi ; 49(17): 4658-4671, 2024 Sep.
Artículo en Zh | MEDLINE | ID: mdl-39307804

RESUMEN

The preparation processes of iron-based organic framework(FeMOF) MIL-100(Fe) and MIL-101(Fe) with two different ligands were optimized and screened, and the optimized FeMOF was loaded with piperlongumine(PL) to enhance the biocompatibility and antitumor efficacy of PL. The MIL-100(Fe) and MIL-101(Fe) were prepared by solvent thermal method using the optimized reaction solvent. With particle size, polymer dispersity index(PDI), and yield as indexes, the optimal preparation processes of the two were obtained by using the definitive screening design(DSD) experiment and establishing a mathematical model, combined with the Derringer expectation function. After characterization, the best FeMOF was selected to load PL by solvent diffusion method, and the process of loading PL was optimized by a single factor combined with an orthogonal experiment. The CCK-8 method was used to preliminarily evaluate the biological safety of blank FeMOF and the antitumor effect of the drug-loaded nano preparations. The experimental results showed that the optimal preparation process of MIL-100(Fe) was as follows: temperature at 127.8 ℃, reaction time of 14.796 h, total solvent volume of 11.157 mL, and feed ratio of 1.365. The particle size of obtained MIL-100(Fe) nanoparticles was(108.84±2.79)nm; PDI was 0.100±0.023, and yield was 36.93%±0.79%. The optimal preparation process of MIL-101(Fe) was as follows: temperature at 128.1 ℃, reaction time of 6 h, total solvent volume of 10.005 mL, and feed ratio of 0.500. The particle size of obtained MIL-101(Fe) nanoparticles was(254.04±22.03)nm; PDI was 0.289±0.052, and yield was 44.95%±0.45%. The optimal loading process of MIL-100(Fe) loaded with PL was as follows: the feed ratio of MIL-100(Fe) to PL was 1∶2; the concentration of PL solution was 7 mg·mL~(-1), and the ratio of DMF to water was 1∶5. The drug loading capacity of obtained MIL-100(Fe)/PL nanoparticles was 68.86%±1.82%; MIL-100(Fe) was nontoxic to HepG2 cells at a dose of 0-120 µg·mL~(-1), and the half-inhibitory concentration(IC_(50)) of free PL for 24 h treatment of HepG2 cells was 1.542 µg·mL~(-1). The IC_(50) value of MIL-100(Fe)/PL was 1.092 µg·mL~(-1)(measured by PL). In this study, the optimal synthesis process of MIL-100(Fe) and MIL-101(Fe) was optimized by innovatively using the DSD to construct a mathematical model combined with the Derringer expectation function. The optimized preparation process of MIL-100(Fe) nanoparticles and the PL loading process were stable and feasible. The size and shape of MIL-100(Fe) particles were uniform, and the crystal shape was good, with a high drug loading capacity, which could significantly enhance the antitumor effect of PL. This study provides a new method for the optimization of the nano preparation process and lays a foundation for the further development and research of antitumor nano preparations of PL.


Asunto(s)
Antineoplásicos , Dioxolanos , Hierro , Estructuras Metalorgánicas , Humanos , Dioxolanos/química , Estructuras Metalorgánicas/química , Antineoplásicos/química , Antineoplásicos/farmacología , Hierro/química , Línea Celular Tumoral , Tamaño de la Partícula , Nanopartículas/química , Portadores de Fármacos/química , Supervivencia Celular/efectos de los fármacos , Composición de Medicamentos/métodos , Proliferación Celular/efectos de los fármacos , Piperidonas
18.
Mol Pain ; 19: 17448069231177634, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37207346

RESUMEN

Chronic pain, along with comorbid psychiatric disorders, is a common problem worldwide. A growing number of studies have focused on non-opioid-based medicines, and billions of funds have been put into digging new analgesic mechanisms. Peripheral inflammation is one of the critical causes of chronic pain, and drugs with anti-inflammatory effects usually alleviate pain hypersensitivity. Sophoridine (SRI), one of the most abundant alkaloids in Chinese herbs, has been proved to exert antitumor, antivirus and anti-inflammation effects. Here, we evaluated the analgesic effect of SRI in an inflammatory pain mouse model induced by complete Freund's adjuvant (CFA) injection. SRI treatment significantly decreased pro-inflammatory factors release after LPS stimuli in microglia. Three days of SRI treatment relieved CFA-induced mechanical hypersensitivity and anxiety-like behavior, and recovered abnormal neuroplasticity in the anterior cingulate cortex of mice. Therefore, SRI may be a candidate compound for the treatment of chronic inflammatory pain and may serve as a structural basis for the development of new drugs.


Asunto(s)
Dolor Crónico , Hiperalgesia , Ratones , Animales , Hiperalgesia/complicaciones , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/inducido químicamente , Adyuvante de Freund/toxicidad , Matrinas , Dolor Crónico/tratamiento farmacológico , Analgésicos/farmacología , Analgésicos/uso terapéutico , Ansiedad/complicaciones , Ansiedad/tratamiento farmacológico
19.
Mol Med ; 29(1): 155, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37940881

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is the third frequently diagnosed cancer with high incidence and mortality rate worldwide. Our previous report has demonstrated that circCOL1A1 (hsa_circ_0044556) functions as an oncogene in CRC, and Gene Ontology (GO) analysis has also revealed the strong association between circCOL1A1 and angiogenesis. However, the mechanism of circCOL1A1 or exosomal circCOL1A1 in CRC angiogenesis remains elusive. METHODS: Purified exosomes from CRC cells were characterized by nanoparticle tracking analyzing, electron microscopy and western blot. qRT-PCR, immunohistochemistry or western blot were employed to test the expression of circCOL1A1, EIF4A3, Smad pathway and angiogenic markers. Cell proliferation of HUVECs was monitored by CCK-8 assay. The migratory and angiogenic capabilities of HUVECs were detected by wound healing and tube formation assay, respectively. Bioinformatics analysis, RNA immunoprecipitation (RIP), RNA pull-down and FISH assays were used to detect the interactions among circCOL1A1, EIF4A3 and Smad2/3 mRNA. The in vitro findings were verified in xenograft model. RESULTS: CRC cell-derived exosomal circCOL1A1 promoted angiogenesis of HUVECs via recruiting EIF4A3. EIF4A3 was elevated in CRC tissues, and it stimulated angiogenesis of HUVECs through directly binding and stabilizing Smad2/3 mRNA. Moreover, exosomal circCOL1A1 promoted angiogenesis via inducing Smad2/3 signaling pathway in vitro, and it also accelerated tumor growth and angiogenesis in vivo. CONCLUSION: CRC cell-derived exosomal circCOL1A1 promoted angiogenesis via recruiting EIF4A3 and activating Smad2/3 signaling.


Asunto(s)
Neoplasias Colorrectales , Exosomas , MicroARNs , Humanos , MicroARNs/genética , Transducción de Señal , Neoplasias Colorrectales/metabolismo , ARN Mensajero/metabolismo , Proliferación Celular , Línea Celular Tumoral , Exosomas/metabolismo , Factor 4A Eucariótico de Iniciación/metabolismo , ARN Helicasas DEAD-box/metabolismo
20.
Small ; 19(20): e2207445, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36840662

RESUMEN

Poor carrier transport capacity and numerous surface defects of charge transporting layers (CTLs), coupled with misalignment of energy levels between perovskites and CTLs, impact photoelectric conversion efficiency (PCE) of inverted perovskite solar cells (PSCs) profoundly. Herein, a collaborative passivation strategy is proposed based on 4-(chloromethyl) benzonitrile (CBN) as a solution additive for fabrication of both [6,6]-phenyl-C61-butyric acid methylester (PCBM) and poly(triarylamine) (PTAA) CTLs. This additive can improve wettability of PTAA and reduce the agglomeration of PCBM particles, which enhance the PCE and device stability of the PSCs. As a result, a PCE exceeding 20% with a remarkable short circuit current of 23.9 mA cm-2 , and an improved fill factor of 81% is obtained for the CBN- modified inverted PSCs. Devices maintain 80% and 70% of the initial PCE after storage under 30% and 85% humidity ambient conditions for 1000 h without encapsulation, as well as negligible light state PCE loss. This strategy demonstrates feasibility of the additive engineering to improve interfacial contact between the CTLs and perovskites for fabrication of efficient and stable inverted PSCs.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA