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1.
Proc Natl Acad Sci U S A ; 120(24): e2219557120, 2023 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-37279273

RESUMEN

It is widely accepted that there is an inextricable link between neural computations, biological mechanisms, and behavior, but it is challenging to simultaneously relate all three. Here, we show that topological data analysis (TDA) provides an important bridge between these approaches to studying how brains mediate behavior. We demonstrate that cognitive processes change the topological description of the shared activity of populations of visual neurons. These topological changes constrain and distinguish between competing mechanistic models, are connected to subjects' performance on a visual change detection task, and, via a link with network control theory, reveal a tradeoff between improving sensitivity to subtle visual stimulus changes and increasing the chance that the subject will stray off task. These connections provide a blueprint for using TDA to uncover the biological and computational mechanisms by which cognition affects behavior in health and disease.


Asunto(s)
Encéfalo , Cognición , Humanos , Cognición/fisiología , Encéfalo/fisiología , Neuronas/fisiología
2.
J Biol Chem ; 300(3): 105712, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38309509

RESUMEN

We recently established a method for the isolation of serum-free oligosaccharides, and characterized various features of their structures. However, the precise mechanism for how these glycans are formed still remains unclarified. To further investigate the mechanism responsible for these serum glycans, here, we utilized rat primary hepatocytes to examine whether they are able to secrete free glycans. Our findings indicated that a diverse array of free oligosaccharides such as sialyl/neutral free N-glycans (FNGs), as well as sialyl lactose/LacNAc-type glycans, were secreted into the culture medium by primary hepatocytes. The structural features of these free glycans in the medium were similar to those isolated from the sera of the same rat. Further evidence suggested that an oligosaccharyltransferase is involved in the release of the serum-free N-glycans. Our results indicate that the liver is indeed secreting various types of free glycans directly into the serum.


Asunto(s)
Hepatocitos , Oligosacáridos , Animales , Ratas , Hepatocitos/metabolismo , Oligosacáridos/sangre , Oligosacáridos/química , Oligosacáridos/metabolismo , Células Hep G2 , Humanos , Masculino , Ratas Wistar
3.
Mol Cell Proteomics ; 22(7): 100582, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37225018

RESUMEN

Carbon metabolism is central to photosynthetic organisms and involves the coordinated operation and regulation of numerous proteins. In cyanobacteria, proteins involved in carbon metabolism are regulated by multiple regulators including the RNA polymerase sigma factor SigE, the histidine kinases Hik8, Hik31 and its plasmid-borne paralog Slr6041, and the response regulator Rre37. To understand the specificity and the cross-talk of such regulations, we simultaneously and quantitatively compared the proteomes of the gene knockout mutants for the regulators. A number of proteins showing differential expression in one or more mutants were identified, including four proteins that are unanimously upregulated or downregulated in all five mutants. These represent the important nodes of the intricate and elegant regulatory network for carbon metabolism. Moreover, serine phosphorylation of PII, a key signaling protein sensing and regulating in vivo carbon/nitrogen (C/N) homeostasis through reversible phosphorylation, is massively increased with a concomitant significant decrease in glycogen content only in the hik8-knockout mutant, which also displays impaired dark viability. An unphosphorylatable PII S49A substitution restored the glycogen content and rescued the dark viability of the mutant. Together, our study not only establishes the quantitative relationship between the targets and the corresponding regulators and elucidated their specificity and cross-talk but also unveils that Hik8 regulates glycogen accumulation through negative regulation of PII phosphorylation, providing the first line of evidence that links the two-component system with PII-mediated signal transduction and implicates them in the regulation of carbon metabolism.


Asunto(s)
Carbono , Synechocystis , Fosforilación , Carbono/metabolismo , Proteómica , Synechocystis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Glucógeno/metabolismo , Nitrógeno , Regulación Bacteriana de la Expresión Génica
4.
BMC Cancer ; 24(1): 71, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38216883

RESUMEN

BACKGROUND: Ras gene mutation and/or overexpression are drivers in the progression of cancers, including colorectal cancer. Blocking the Ras signaling has become a significant strategy for cancer therapy. Previously, we constructed a recombinant scFv, RGD-p21Ras-scFv by linking RGD membrane-penetrating peptide gene with the anti-p21Ras scFv gene. Here, we expressed prokaryotically RGD-p21Ras-scFv on a pilot scale, then investigated the anti-tumor effect and the mechanism of blocking Ras signaling. METHODS: The E. coli bacteria which could highly express RGD-p21Ras-scFv was screened and grown in 100 L fermentation tank to produce RGD-p21Ras-scFv on optimized induced expression conditions. The scFv was purified from E. coli bacteria using His Ni-NTA column. ELISA was adopted to test the immunoreactivity of RGD-p21Ras-scFv against p21Ras proteins, and the IC50 of RGD-p21Ras-scFv was analyzed by CCK-8. Immunofluorescence colocalization and pull-down assays were used to determine the localization and binding between RGD-p21Ras-scFv and p21Ras. The interaction forces between RGD-p21Ras-scFv and p21Ras after binding were analyzed by molecular docking, and the stability after binding was determined by molecular dynamics simulations. p21Ras-GTP interaction was detected by Ras pull-down. Changes in the MEK-ERK /PI3K-AKT signaling paths downstream of Ras were detected by WB assays. The anti-tumor activity of RGD-p21Ras-scFv was investigated by nude mouse xenograft models. RESULTS: The technique of RGD-p21Ras-scFv expression on a pilot scale was established. The wet weight of the harvested bacteria was 31.064 g/L, and 31.6 mg RGD-p21Ras-scFv was obtained from 1 L of bacterial medium. The purity of the recombinant antibody was above 85%, we found that the prepared on a pilot scale RGD-p21Ras-scFv could penetrate the cell membrane of colon cancer cells and bind to p21Ras, then led to reduce of p21Ras-GTP (active p21Ras). The phosphorylation of downstream effectors MEK-ERK /PI3K-AKT was downregulated. In vivo antitumor activity assays showed that the RGD-p21Ras-scFv inhibited the proliferation of colorectal cancer cell lines. CONCLUSION: RGD-p21Ras-scFv prokaryotic expressed on pilot-scale could inhibited Ras-driven colorectal cancer growth by partially blocking p21Ras-GTP and might be able to be a hidden therapeutic antibody for treating RAS-driven tumors.


Asunto(s)
Neoplasias Colorrectales , Escherichia coli , Ratones , Animales , Humanos , Escherichia coli/genética , Simulación del Acoplamiento Molecular , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Guanosina Trifosfato , Quinasas de Proteína Quinasa Activadas por Mitógenos , Proteínas Proto-Oncogénicas p21(ras)/genética
5.
PLoS Comput Biol ; 19(1): e1010843, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36626362

RESUMEN

Neural activity in the cortex is highly variable in response to repeated stimuli. Population recordings across the cortex demonstrate that the variability of neuronal responses is shared among large groups of neurons and concentrates in a low dimensional space. However, the source of the population-wide shared variability is unknown. In this work, we analyzed the dynamical regimes of spatially distributed networks of excitatory and inhibitory neurons. We found chaotic spatiotemporal dynamics in networks with similar excitatory and inhibitory projection widths, an anatomical feature of the cortex. The chaotic solutions contain broadband frequency power in rate variability and have distance-dependent and low-dimensional correlations, in agreement with experimental findings. In addition, rate chaos can be induced by globally correlated noisy inputs. These results suggest that spatiotemporal chaos in cortical networks can explain the shared variability observed in neuronal population responses.


Asunto(s)
Modelos Neurológicos , Dinámicas no Lineales , Neuronas/fisiología , Red Nerviosa/fisiología
6.
Nutr Metab Cardiovasc Dis ; 34(5): 1295-1304, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38508994

RESUMEN

BACKGROUND AND AIM: Diabetes retinopathy (DR) is a common microvascular complication of diabetes, and it is the main cause of global vision loss. The current observational research results show that the causal relationship between Vitamin D and DR is still controversial. Therefore, we conducted a Mendelian randomization study to determine the potential causal relationship between serum 25-hydroxyvitamin D 25(OH)D and DR. METHODS AND RESULTS: In this study, we selected aggregated data on serum 25(OH)D levels (GWAS ID: ebi-a-GCST90000615) and DR (GWAS ID: finn-b-DM_RETINOPATHY) from a large-scale GWAS database. Then use MR analysis to evaluate the possible causal relationship between them. We mainly use inverse variance weighted (IVW), supplemented by MR Egger and weighted median methods. Sensitivity analysis is also used to ensure the stability of the results, such as Cochran's Q-test, MR-PRESSO, MR-Egger interception test, and retention method. The MR analysis results showed that there was no significant causal relationship between 25(OH)D and DR (OR = 1.0128, 95%CI=(0.9593,1.0693), P = 0.6447); Similarly, there was no significant causal relationship between DR and serum 25 (OH) D levels (OR = 0.9900, 95% CI=(0.9758,1.0045), P = 0.1771). CONCLUSION: Our study found no significant causal relationship between serum 25(OH)D levels and DR, and vice versa. A larger sample size randomized controlled trial is needed to further reveal its potential causal relationship.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Enfermedades de la Retina , Humanos , Análisis de la Aleatorización Mendeliana , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/epidemiología , Retinopatía Diabética/genética , Vitamina D , Bases de Datos Factuales , Estudio de Asociación del Genoma Completo
7.
Mol Cell Proteomics ; 21(12): 100440, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36356940

RESUMEN

Ascorbate peroxidase (APEX)-based proximity labeling coupled with mass spectrometry has a great potential for spatiotemporal identification of proteins proximal to a protein complex of interest. Using this approach is feasible to define the proteome neighborhood of important protein complexes in a popular photosynthetic model cyanobacterium Synechocystis sp. PCC6803 (hereafter named as Synechocystis). To this end, we developed a robust workflow for APEX2-based proximity labeling in Synechocystis and used the workflow to identify proteins proximal to the photosystem II (PS II) oxygen evolution complex (OEC) through fusion APEX2 with a luminal OEC subunit, PsbO. In total, 38 integral membrane proteins (IMPs) and 93 luminal proteins were identified as proximal to the OEC. A significant portion of these proteins are involved in PS II assembly, maturation, and repair, while the majority of the rest were not previously implicated with PS II. The IMPs include subunits of PS II and cytochrome b6/f, but not of photosystem I (except for PsaL) and ATP synthases, suggesting that the latter two complexes are spatially separated from the OEC with a distance longer than the APEX2 labeling radius. Besides, the topologies of six IMPs were successfully predicted because their lumen-facing regions exclusively contain potential APEX2 labeling sites. The luminal proteins include 66 proteins with a predicted signal peptide and 57 proteins localized also in periplasm, providing important targets to study the regulation and selectivity of protein translocation. Together, we not only developed a robust workflow for the application of APEX2-based proximity labeling in Synechocystis and showcased the feasibility to define the neighborhood proteome of an important protein complex with a short radius but also discovered a set of the proteins that potentially interact with and regulate PS II structure and function.


Asunto(s)
Complejo de Proteína del Fotosistema II , Synechocystis , Complejo de Proteína del Fotosistema II/metabolismo , Proteoma/metabolismo , Oxígeno/metabolismo , Complejo de Proteína del Fotosistema I/metabolismo , Synechocystis/metabolismo
8.
J Proteome Res ; 22(4): 1255-1269, 2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-36930737

RESUMEN

Spatial proteome reorganization in response to a changing environment represents a different layer of adaptation mechanism in addition to differential expression of a subset of stress responsive genes in photosynthetic organisms. Profiling such reorganization events is critically important to extend our understanding how photosynthetic organisms adapt to adverse environments. Thus, we treated a unicellular photosynthetic model cyanobacterium, Synechocystis sp. PCC 6803 (hereafter referred to as Synechocystis), with five different types of abiotic stresses including nitrogen starvation, iron deficiency, cold, heat, and darkness, and systematically identified proteins showing stress-induced differential expression and/or redistribution between the membrane and the soluble fractions using a quantitative proteomics approach. A number of proteins showing such a redistribution in response to a single or multiple types of abiotic stresses were identified. These include 12 ribosomal proteins displaying unanimous cold-induced redistribution to the membrane and the protein FurA, a master regulator of iron acquisition, displaying iron deficiency- and nitrogen starvation-induced redistribution to the membrane. Such findings shed light on a novel regulatory mechanism underlying the corresponding stress responses, and establish the results in the present study as an important resource for future studies intended to understand how photosynthetic organisms cope with adverse environments.


Asunto(s)
Deficiencias de Hierro , Synechocystis , Humanos , Proteoma/genética , Proteoma/metabolismo , Estrés Fisiológico , Synechocystis/genética , Synechocystis/metabolismo , Nitrógeno/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
9.
J Neurochem ; 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36625269

RESUMEN

Alzheimer's disease (AD) is a highly heritable disease. The morphological changes of cortical cortex (such as, cortical thickness and surface area) in AD always accompany by the change of the functional connectivity to other brain regions and influence the short- and long-range brain network connections, causing functional deficits of AD. In this study, the first hypothesis is that genetic variations might affect morphology-based brain networks, leading to functional deficits; the second hypothesis is that protein-protein interaction (PPI) between the candidate proteins and known interacting proteins to AD might exist and influence AD. 600 470 variants and structural magnetic resonance imaging scans from 175 AD patients and 214 healthy controls were obtained from the Alzheimer's Disease Neuroimaging Initiative-1 database. A co-sparse reduced-rank regression model was fit to study the relationship between non-synonymous mutations and morphology-based brain networks. After that, PPIs between selected genes and BACE1, an enzyme that was known to be related to AD, are explored by using molecular dynamics (MD) simulation and co-immunoprecipitation (Co-IP) experiments. Eight genes affecting morphology-based brain networks were identified. The results of MD simulation showed that the PPI between TGM4 and BACE1 was the strongest among them and its interaction was verified by Co-IP. Hence, gene variations influence morphology-based brain networks in AD, leading to functional deficits. This finding, validated by MD simulation and Co-IP, suggests that the effect is robust.

10.
Pediatr Res ; 93(7): 1883-1890, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36329225

RESUMEN

BACKGROUND: This study aimed to explore the functions of ubiquitin-specific protease 5 (USP5) in the endothelial inflammation of Kawasaki disease (KD). METHODS: USP5 expression levels in HCAECs were examined after stimulation with TNFα or KD sera. The inflammatory cytokine expression level and nuclear factor κB (NF-κB) signaling activation proteins were also investigated in HCAECs by using USP5 overexpression/knockdown lentivirus as well as its small molecule inhibitor vialinin A. RESULTS: USP5 expression level is upregulated in HCAECs after stimulation with KD sera. Similarly, the USP5 expression level is also increased in a time- and dose-dependent manner upon TNFα stimulation in HCAECs. Moreover, USP5 sustains proinflammatory cytokine production and NF-κB signaling activation, whereas USP5 knockdown causes the proinflammatory cytokine levels to decrease and suppress NF-κB signaling activation. Notably, the USP5 inhibitor vialinin A can suppress the expression of inflammatory genes induced by TNFα and IL-1ß in HCAECs. CONCLUSIONS: Our study identified USP5 as a positive regulator of TNFα production and its downstream signaling activation during the inflammatory responses in HCAECs, and demonstrated that its inhibitor vialinin A might serve as a candidate drug for KD therapy to prevent the excessive production of proinflammatory cytokines. IMPACT: USP5 is upregulated in human coronary artery endothelial cells (HCAECs) whether incubated with acute KD sera or TNFα in vitro. USP5 promotes proinflammatory cytokine expression by sustaining NF-κB signaling activation in HCAECs. The USP5 inhibitor vialinin A can suppress the expression levels of proinflammatory cytokines in HCAEC, thus providing a novel mechanism and intervention strategy in KD therapy.


Asunto(s)
Síndrome Mucocutáneo Linfonodular , Proteasas Ubiquitina-Específicas , Humanos , Citocinas/metabolismo , Células Endoteliales/metabolismo , Inflamación/metabolismo , Síndrome Mucocutáneo Linfonodular/metabolismo , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo
11.
Mol Cell Proteomics ; 20: 100162, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34655801

RESUMEN

Light is essential for photosynthetic organisms and is involved in the regulation of protein synthesis and degradation. The significance of light-regulated protein degradation is exemplified by the well-established light-induced degradation and repair of the photosystem II reaction center D1 protein in higher plants and cyanobacteria. However, systematic studies of light-regulated protein degradation events in photosynthetic organisms are lacking. Thus, we conducted a large-scale survey of protein degradation under light or dark conditions in the model cyanobacterium Synechocystis sp. PCC 6803 (hereafter referred to as Synechocystis) using the isobaric labeling-based quantitative proteomics technique. The results revealed that 79 proteins showed light-regulated degradation, including proteins involved in photosystem II structure or function, quinone binding, and NADH dehydrogenase. Among these, 25 proteins were strongly dependent on light for degradation. Moreover, the light-dependent degradation of several proteins was sensitive to photosynthetic electron transport inhibitors (DCMU and DBMIB), suggesting that they are influenced by the redox state of the plastoquinone (PQ) pool. Together, our study comprehensively cataloged light-regulated protein degradation events, and the results serve as an important resource for future studies aimed at understanding light-regulated processes and protein quality control mechanisms in cyanobacteria.


Asunto(s)
Proteínas Bacterianas/efectos de la radiación , Luz , Synechocystis , Proteolisis
12.
Int J Clin Pract ; 2023: 8215866, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37547098

RESUMEN

Background: Serum uric acid (SUA) was closely related to body metabolism. This study aimed to investigate the relationship between the adult weight-adjusted waist index (WWI) and SUA. Methods: In the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2020, 6494 eligible participants aged ≥20 were included. The multivariate logistic regression model was used to test the correlation between WWI and SUA. At the same time, subgroup analysis was carried out by using multivariate logistic regression according to age, sex, and race. Then, the fitting smooth curve was applied to solve the association between WWI and SUA. Finally, the recursive algorithm was used to calculate the inflection point in the nonlinear relationship, and the two-stage piecewise linear regression model was used to analyze the relationship between WWI and SUA on both sides of the inflection point. Results: In all the 6494 participants, through the fully adjusted model, this study found that there was a positive correlation between WWI and SUA (ß = 5.64; 95% CI: 2.62 and 8.66). In addition, this positive correlation still had certain statistical significance in the subgroup analysis stratified by sex, age, and race. Our research team found a significant positive correlation between the WWI and SUA in females, but the correlation was not significant in males. We also found a small inverted U-shaped curve between the WWI and SUA in men when we stratified the sex subgroups. The small inflection point was determined to be 11.5 cm/√ kg. In racial subgroup analysis, we also found a U-shaped relationship between the WWI and SUA in non-Hispanic White and other race/ethnicity (the inflection point was 11.08 cm/√ kg and 12.14 cm/√ kg, respectively). Conclusion: This study showed that the WWI was a newly developed and new predictor of centripetal obesity independent of body weight and there was a positive correlation between the WWI and SUA.


Asunto(s)
Obesidad , Ácido Úrico , Adulto , Masculino , Femenino , Humanos , Estudios Transversales , Encuestas Nutricionales , Peso Corporal
13.
Glycobiology ; 32(4): 314-332, 2022 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-34939097

RESUMEN

Recent studies demonstrated the occurrence of sialyl free N-glycans (FNGs) in sera from a variety of animals. Unlike the intracellular FNGs that mainly carry a single N-acetylglucosamine at their reducing termini (Gn1-type), these extracellular FNGs have an N,N'-diacetylchitobiose at their reducing termini (Gn2-type). The detailed mechanism for how they are formed, however, remains unclarified. In this study, we report on an improved method for isolating FNGs from sera and found that, not only sialyl FNGs, but also neutral FNGs are present in animal sera. Most of the neutral oligomannose-type FNGs were found to be Gn1-type. We also found that a small portion of sialyl FNGs were Gn1-type. The ratio of Gn1-type sialyl FNGs varies between species, and appears to be partially correlated with the distribution of lysosomal chitobiase activity. We also identified small sialylated glycans similar to milk oligosaccharides, such as sialyl lactose or sialyl N-acetyllactosamine in sera. Our results indicate that there are varieties of free oligosaccharides in sera and the mechanism responsible for their formation is more complicated than currently envisaged.


Asunto(s)
Oligosacáridos , Polisacáridos , Acetilglucosamina , Animales , Citosol
14.
Opt Express ; 30(14): 24703-24715, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-36237018

RESUMEN

This letter presents a fabricated Dirac point modulator of a graphene-based terahertz electromagnetically induced transparency (EIT)-like metasurface (GrE & MS). Dynamic modulation is realized by applying three stimulus modes of optical pump, bias voltage, and optical pump-bias voltage combination. With increasing luminous flux or bias voltage, the transmission amplitude undergoes two stages: increasing and decreasing, because the graphene Fermi level shifts between the valence band, Dirac point, and conduction band. Thus, an approximate position of the Dirac point can be evaluated by the transmission spectrum fluctuation. The maximum modulation depth is measured to be 182% under 1 V. These findings provide a method for designing ultrasensitive terahertz modulation devices.

15.
Vet Res ; 53(1): 3, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35012652

RESUMEN

Trueperella pyogenes (T. pyogenes) is an opportunistic pathogen associated with a variety of diseases in many domestic animals. Therapeutic treatment options for T. pyogenes infections are becoming limited due to antimicrobial resistance, in which efflux pumps play an important role. This study aims to evaluate the inhibitory activity of luteolin, a natural flavonoid, on the MsrA efflux pump and investigate its mechanism. The results of antimicrobial susceptibility testing indicated that the susceptibility of msrA-positive T. pyogenes isolates to six macrolides increased after luteolin treatment, while the susceptibility of msrA-negative isolates showed no change after luteolin treatment. It is suspected that luteolin may increase the susceptibility of T. pyogenes isolates by inhibiting MsrA activity. After 1/2 MIC luteolin treatment for 36 h, the transcription level of the msrA gene and the expression level of the MsrA protein decreased by 55.0-97.7% and 36.5-71.5%, respectively. The results of an affinity test showed that the equilibrium dissociation constant (KD) of luteolin and MsrA was 6.462 × 10-5 M, and hydrogen bonding was predominant in the interaction of luteolin and MsrA. Luteolin may inhibit the ATPase activity of the MsrA protein, resulting in its lack of an energy source. The current study illustrates the effect of luteolin on MsrA in T. pyogenes isolates and provides insight into the development of luteolin as an innovative agent in combating infections caused by antimicrobial-resistant bacteria.


Asunto(s)
Actinomycetaceae , Farmacorresistencia Bacteriana , Luteolina , Macrólidos , Actinomycetaceae/efectos de los fármacos , Animales , Animales Domésticos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana/efectos de los fármacos , Luteolina/farmacología , Macrólidos/farmacología , Pruebas de Sensibilidad Microbiana/veterinaria
16.
Inorg Chem ; 61(3): 1512-1520, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34969248

RESUMEN

Maintaining a long-term continuous and stable reactivator blood concentration to treat organophosphorus nerve agent poisoning using acetylcholinesterase (AChE) reactivator pralidoxime chloride (2-PAM) is very important yet difficult. Because the flexible framework of MIL-88B(Fe) nanoparticles (NPs) can swell in polar solvents, pralidoxime chloride (2-PAM) was loaded in MIL-88B(Fe) NPs (size: ca. 500 nm) by stirring and incubation in deionized water to obtain 2-PAM@MIL-88B(Fe), which had a maximum drug loading capacity of 12.6 wt %. The as-prepared composite was characterized by IR, powder X-ray diffraction (P-XRD), scanning electron microscopy (SEM), ζ-potential, Brunauer-Emmett-Teller (BET), and thermogravimetry/differential thermal analysis (TG/DTA). The results showed that under constant conditions, the maximum drug release rates of 2-PAM@MIL-88B(Fe) in absolute ethanol, phosphate-buffered saline (PBS) solution (pH = 7.4), and PBS solution (pH = 4) at 150 h were 51.7, 80.6, and 67.1%, respectively. This was because the composite showed different swelling behaviors in different solvents. In PBS solution with pH = 2, the 2-PAM@MIL-88B(Fe) framework collapsed after 53 h and released 100% of 2-PAM. For mice after intragastric poisoning with sarin (a neurotoxic agent), an atropine-assisted 2-PAM@MIL-88B(Fe) treatment experiment revealed that 2-PAM@MIL-88B(Fe) continuously released 2-PAM for more than 72 h so that poisoned AChE was continuously and steadily reactivated. The reactivation rate of AChE was 56.7% after 72 h. This composite is expected to provide a prolonged, stable therapeutic drug for the mid- and late-stage treatment of neurotoxic agent poisoning.


Asunto(s)
Estructuras Metalorgánicas/química , Agentes Nerviosos/farmacología , Compuestos de Pralidoxima/farmacología , Sarín/antagonistas & inhibidores , Acetilcolinesterasa/análisis , Acetilcolinesterasa/metabolismo , Administración Oral , Animales , Atropina/administración & dosificación , Atropina/farmacología , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Ratones Endogámicos , Nanopartículas/química , Agentes Nerviosos/química , Compuestos de Pralidoxima/administración & dosificación , Compuestos de Pralidoxima/química , Sarín/administración & dosificación , Sarín/toxicidad
17.
Appl Opt ; 61(8): 2103-2107, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35297903

RESUMEN

A novel, to the best of our knowledge, four-band tunable absorber sensor, based on a graphene layer, is presented. The proposed sensor configuration is composed of a single monolayer of graphene placed on top of a SiO2 dielectric substrate, whereas a gold grounding plane is placed beneath the SiO2. In addition, the resonant frequencies of the sensor can be directly controlled by adjusting the Fermi level of graphene, while the absorption rate reaches a value greater than 99% at all resonant peaks. The acquired calculation results of the refractive index sensitivity of our proposed sensor show that the four resonant peaks possess superior sensing characteristics. Additionally, by covering the measured objects with different refractive indices, the acquired results indicate that the sensing performance of the sensor exhibits good linearity. From our analysis, it is concluded that the absorbing sensor exhibits a broad range of potential applications in the biomedical field.

18.
Zhongguo Zhong Yao Za Zhi ; 47(12): 3251-3257, 2022 Jun.
Artículo en Zh | MEDLINE | ID: mdl-35851118

RESUMEN

This study aims to establish a method for the component content determination and fingerprint evaluation of Mori Cortex, fried Mori Cortex and its standard decoction, and to reveal the quality transfer law among the three based on transfer rate, extraction rate, and fingerprint similarity.Fifteen representative batches of Mori Cortex decoction pieces were collected to prepare fried Mori Cortex and its standard decoction.UPLC-PDA was employed to establish the content determination method and fingerprint.The established UPLC method and fingerprint could be applied to the detection of Mori Cortex, fried Mori Cortex and its standard decoction.The UPLC fingerprints of the 15 batches of Mori Cortex and fried Mori Cortex had good similarity(>0.9) and the same common peaks.However, only one characteristic peak(mulberroside A) could be observed in the fingerprint of fried Mori Cortex standard decoction, which indicated that the corresponding components of other common peaks in the fingerprint of Mori Cortex had low content in the water extract.The extraction rates of mulberroside A from Mori Cortex, fried Mori Cortex and its standard decoction were 1.49%-2.00%, 1.62%-2.27% and 0.75%-1.29%, respectively.Mulberroside A showed the transfer rate of 103.7%-116.3% from Mori Cortex to fried Mori Cortex and 45.7%-56.9% from fried Mori Cortex to its standard decoction.The extraction rates of the 15 batches of fried Mori Cortex standard decoctions were 14.7%-19.5%.All the above indicators were within±30% of the mean value.This study established a method for the determination of mulberroside A content and fingerprint of Mori Cortex, fried Mori Cortex and its standard decoction, and clarified the quality transfer law among the three.It established the method for quality evaluation of Mori Cortex and fried Mori Cortex and can provide reference for the whole-process quality control in the preparation of the agents containing fried Mori Cortex.


Asunto(s)
Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Control de Calidad
19.
Aging Clin Exp Res ; 33(8): 2317-2325, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34159534

RESUMEN

BACKGROUND: COVID-19 is erupting globally. Mass quarantine had been implemented all around China which could influence the psychological status of patients with memory disorders and their caregivers. AIM: To investigate the psychological impact of mass quarantine on patients with memory disorders and their caregivers in China. METHODS: We completed a cross-sectional study in 787 patients and their caregivers registered from 2010 to 2019 in Memory Clinic, The First Affiliated Hospital of Chongqing Medical University, by telephone interviews. The performance in neuropsychiatric symptoms (NPSs), sleep, nutrition, chronic diseases of patients, and the burden of care, anxiety and depression of caregivers was assessed by six assessment scales (MNA-SF, PSQI, NPI, RSS, PHQ-9 and GAD-7). RESULTS: Only 68 (8.6%) patients worried about the outbreak of COVID-19. The prevalence of NPSs among all subjects was nearly 60.0%. Approximately 50.0% of the caregivers reported distress. More than 70.0% of patients remained stable in NPSs. However, anxiety, depression, aberrant motor disorder and delusion were exacerbated (22.9%, 18.6%, 17.1% and 16.8%, respectively). Appetite and eating disorder led alleviation rate by 25.8% while disappearing rate of agitation led by 5.8%. 7.5% of caregivers manifested depressive symptoms while 4.9% expressed anxiety symptoms, and 40.8% showed care burden. The coefficients of RSS and PHQ-9, RSS and GAD-7, RSS and NPI-D, PHQ-9 and GAD-7 were 0.7, 0.5, 0.5 and 0.6, respectively (p < 0.01). CONCLUSION: Changes in NPSs during COVID-19 were observed in some patients with memory disorders and their caregivers, and adherence to medication contributed to the stabilization of NPSs.


Asunto(s)
COVID-19 , Demencia , Ansiedad/epidemiología , Cuidadores , China/epidemiología , Estudios Transversales , Humanos , Trastornos de la Memoria/epidemiología , SARS-CoV-2
20.
Pharm Biol ; 59(1): 382-390, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33794128

RESUMEN

CONTEXT: Pueraria lobata (Willd.) Ohwi (Fabaceae) root extract can lower blood glucose levels; however, whether Pueraria lobata root polysaccharide (PLP) possesses these effects is still unknown. OBJECTIVE: This study evaluates the therapeutic effect of PLP on diabetic metabolic syndrome. MATERIALS AND METHODS: The db/m mice were assigned to normal control group (NC), db/db mice were divided into four groups randomly (n = 8). The db/db mice received rosiglitazone (10 mg/kg BW) or PLP (100 or 200 mg/kg BW) via oral gavage for 6 weeks. Afterward, blood glucose, insulin, and glycogen content were assayed, and insulin tolerance test (ITT), oral glucose tolerance test (OGTT) were performed. Glucose and lipid metabolism-related parameters and gene expression levels were assayed by ELISA and RT-PCR, respectively. RESULTS: After treatment with HPLP, the values of body weight, epididymal fat, subcutaneous fat, fasting blood glucose, insulin, and HOMA-IR decreased to 45.89 ± 1.66 g, 1.65 ± 0.14 g, 1.97 ± 0.16 g, 14.84 ± 1.52 mM, 9.35 ± 0.98 mU/L, and 5.56 ± 1.26, respectively; the levels of TG, TC, LDL-C, and FFA decreased to 1.67 ± 0.11 mmol/L, 6.23 ± 0.76 mmol/L, 1.29 ± 0.07 mmol/L, and 1.71 ± 0.16 mmol/L, respectively. HPLP down-regulated PEPCK, G6PC, FOXO1, SREBP-1, and ACC mRNA expression (p < 0.01), and up-regulated GS, Akt2, PI3K, GLUT2, PPARα, and LDLR mRNA expression in the liver (p < 0.01). DISCUSSION AND CONCLUSION: PLP exerts antidiabetic effects via activating the PI3K/AKT signalling pathway, thus improving insulin resistance, glucose, and lipid metabolism in db/db mice. Thus, PLP may be considered as a potential antidiabetic agent in clinical therapy.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Polisacáridos/farmacología , Pueraria/química , Animales , Glucemia/efectos de los fármacos , Diabetes Mellitus Experimental/fisiopatología , Relación Dosis-Respuesta a Droga , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/aislamiento & purificación , Insulina/sangre , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Raíces de Plantas , Polisacáridos/administración & dosificación , Polisacáridos/aislamiento & purificación , Distribución Aleatoria , Rosiglitazona/farmacología , Transducción de Señal/efectos de los fármacos
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