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1.
Neural Regen Res ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38993123

RESUMEN

ABSTRACT: AAV-PHP.eB is an artificial adeno-associated virus (AAV) that crosses the blood-brain barrier and targets neurons more efficiently than other AAVs when administered systematically. While AAV-PHP.eB has been used in various disease models, its cellular tropism in cerebrovascular diseases remains unclear. In the present study, we aimed to elucidate the tropism of AAV-PHP.eB for different cell types in the brain in a mouse model of ischemic stroke and evaluate its effectiveness in mediating basic fibroblast growth factor (bFGF) gene therapy. Mice were injected intravenously with AAV-PHP.eB either 14 days prior to (pre-stroke) or 1 day following (post-stroke) transient middle cerebral artery occlusion. Notably, we observed a shift in tropism from neurons to endothelial cells with post-stroke administration of AAV-PHP.eB-mNeonGreen (mNG). This endothelial cell tropism correlated strongly with expression of the endothelial membrane receptor lymphocyte antigen 6 family member A (Ly6A). Furthermore, AAV-PHP.eB-mediated overexpression of bFGF markedly improved neurobehavioral outcomes and promoted long-term neurogenesis and angiogenesis post-ischemic stroke. Our findings underscore the significance of considering potential tropism shifts when utilizing AAV-PHP.eB-mediated gene therapy in neurological diseases and suggest a promising new strategy for bFGF gene therapy in stroke treatment.

2.
Phys Chem Chem Phys ; 26(24): 17370-17382, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38860760

RESUMEN

The concept of aromaticity is primarily invented to account for the high stability of conjugated organic compounds that possess a specific structural and chemical stability with (4n + 2) π electrons. In 1988, quasi-aromaticity was theoretically proposed for the Mo3S44+ core in the Mo3(µ3-S)(µ-S)3(χ-dtp)3(µ-dtp) L compound (χ: chelating ligand; dtp: (EtO)2PS2-) illustrated by canonical molecular orbitals. However, the origin of the quasi-aromaticity and chemical bonding remains ambiguous, lacking a thorough analysis in terms of stability and quantitative measurement of the aromatic character. Thus, in this work, we systematically reported the electronic structure and aromaticity of a series of polynuclear metal chalcogenide clusters [M3X4(H2O)9]4+ (M = Cr, Mo, W, and Sg; X = O, S, Se, and Te) to explore an efficient tool of NICS index values at specific points to measure the quasi-aromaticity and to figure out the (d-p-d) π three-center bonding as the predominant origin from the arrangement of three Mo atoms and three bridged X atoms. Interestingly, derived from the Mo3⋯S3 quasi-plane, the extended sandwich cluster model of a S3⋯Mo3⋯S3 (Mo3S6) structure can be seen as the seed unit of the popular MoS2 nanomaterials, with the resemblance between both molecular and periodic systems regarding geometries, electronic structures, and chemical bonding. Additionally, the highly symmetric Mo3S4 core in [Mo3X4(H2O)9]4+ can be arranged in a staggered and stacked manner to create the Mo6S82- building block, corresponding to the crystalline structures in BaMo6S8 Chevrel phases, albeit with slight deformations. But the neutral Mo6S8 cluster can be seen as the seed structure for the Mo3S4 periodic materials for the high resemblance in terms of geometry, electronic structures and chemical bonding. Drawing upon the observed similarities between cluster models and materials, we propose a new concept termed "cluster-assembly" materials. This concept involves the expansion from a high-symmetry and/or aromatic stable cluster seed unit to form the corresponding derivative materials, presenting an alternative paradigm for investigating crystals and enriching our comprehension of the stabilities exhibited by both gas-phase clusters and solid-state materials. The concept of "cluster-assembly" materials not only contributes to the formulation of design strategies for novel materials or stable clusters but also provides valuable insights into the extension of periodic aromaticity.

3.
Stat Med ; 43(19): 3689-3701, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-38894557

RESUMEN

The Cox regression model or accelerated failure time regression models are often used for describing the relationship between survival outcomes and potential explanatory variables. These models assume the studied covariates are connected to the survival time or its distribution or their transformations through a function of a linear regression form. In this article, we propose nonparametric, nonlinear algorithms (deepAFT methods) based on deep artificial neural networks to model survival outcome data in the broad distribution family of accelerated failure time models. The proposed methods predict survival outcomes directly and tackle the problem of censoring via an imputation algorithm as well as re-weighting and transformation techniques based on the inverse probabilities of censoring. Through extensive simulation studies, we confirm that the proposed deepAFT methods achieve accurate predictions. They outperform the existing regression models in prediction accuracy, while being flexible and robust in modeling covariate effects of various nonlinear forms. Their prediction performance is comparable to other established deep learning methods such as deepSurv and random survival forest methods. Even though the direct output is the expected survival time, the proposed AFT methods also provide predictions for distributional functions such as the cumulative hazard and survival functions without additional learning efforts. For situations where the popular Cox regression model may not be appropriate, the deepAFT methods provide useful and effective alternatives, as shown in simulations, and demonstrated in applications to a lymphoma clinical trial study.


Asunto(s)
Algoritmos , Simulación por Computador , Redes Neurales de la Computación , Dinámicas no Lineales , Modelos de Riesgos Proporcionales , Humanos , Análisis de Supervivencia , Aprendizaje Profundo , Modelos Estadísticos
4.
Phys Chem Chem Phys ; 26(22): 16091-16095, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38780310

RESUMEN

In light of recently reported monovalent lanthanide in borozene complexes LnB8- (Ln = La, Pr, Tb, Tm, Yb), the corresponding AnB8- (An = Ac, Pa, Bk, Md, No) actinide species within the same group were theoretically investigated in respect of oxidation state, stability, electronic structure and chemical bonding pattern. Our investigations reveal the feasibility of actinides, especially for the late actinide borozene compounds (BkB8-, MdB8-, NoB8-) adopting a monovalent oxidation state of +I, a phenomenon fine-tuned by the doubly aromatic borozene B82-. Early actinides (AcB8-, PaB8-) however exhibit a tendency towards higher trivalent oxidation states.

5.
Nanomaterials (Basel) ; 14(8)2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38668179

RESUMEN

Biowaste conversion into activated carbon is a sustainable and inexpensive approach that relieves the pressure on its disposal. Here, we prepared micro-mesoporous activated carbons (ACs) from cucumber peels through carbonization at 600 °C followed by thermal activation at different temperatures. The ACs were tested as supercapacitors for the first time. The carbon activated at 800 °C (ACP-800) showed a high specific capacitance value of 300 F/g at a scan rate of 5 mV/s in the cyclic voltammetry and 331 F/g at the current density of 0.1 A/g in the galvanostatic charge-discharge analysis. At the current density of 1 A/g, the specific discharge capacitance was 286 F/g and retained 100% capacity after 2000 cycles. Their properties were analyzed by scanning electron microscopy, energy-dispersive X-ray analysis, porosity, thermal analysis, and Fourier-transform infrared spectroscopy. The specific surface area of this sample was calculated to be 2333 m2 g-1 using the Brunauer-Emmett-Teller method. The excellent performance of ACP-800 is mainly attributed to its hierarchical porosity, as the mesopores provide connectivity between the micropores and improve the capacitive performance. These electrochemical properties enable this carbon material prepared from cucumber peels to be a potential source for supercapacitor materials.

6.
Biomedicines ; 12(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38672108

RESUMEN

Recently, immunotherapy has arisen as a novel treatment approach for patients with colorectal cancer (CRC), but the effectiveness of immunotherapy varies in these patients. We hypothesized that immune checkpoint molecules (ICMs), which are the targets of immunotherapy, are often exhibited concomitantly. Our objective was to investigate the patterns of ICM expression in patients with CRC and the differences in ICM expression based on microsatellite instability status. The immunohistochemical expression of programmed cell death protein 1 (PD-1), programmed cell death ligand 1 (PD-L1), T cell immunoglobulin and mucin-domain containing-3 (TIM-3), and lymphocyte-activation gene 3 (LAG-3) in the tumor center and periphery was assessed in patients with non-metastatic colorectal cancer. We enrolled 83 patients with CRC: a total of 40 microsatellite-stable (MSS) and 43 microsatellite-instability-high (MSI-H) cancer patients. PD-L1 was more frequently expressed in the tumor center in the MSI-H patients with than that in the MSS patients (18 [41.9%] vs. 3 [7.5%], respectively; p < 0.001), and the same trend was observed for TIM-3 expression (30 [69.8%] vs. 19 [47.5%], respectively; p = 0.047). The concomitant expression of two or more ICMs was more frequently observed than no expression or the expression of a single molecule in both the MSS and MSI-H groups; a total of 34 (79.7%) patients with MSI-H cancer and 23 (57.5%) with MSS cancer showed ICM expression at the tumor center, whereas 34 (79.7%) patients with MSI-H cancer and 22 (55%) with MSS cancer showed expression at the tumor periphery. Patients with the genetic characteristics of MSI-H cancer showed higher expression levels of ICMs than those in patients with MSS cancer, and predominantly, two or more ICMs were concurrently expressed. Our findings highlight the potential efficacy of the dual-blockade approach in immunotherapy, particularly in patients with MSI-H CRC.

7.
ACS Appl Bio Mater ; 7(3): 1588-1599, 2024 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-38437727

RESUMEN

The synthesis of copper nanoparticles (CuNPs) was accomplished by using a rapid, green, and versatile argon plasma reduction method that involves solvent extraction. With this method, a plasma-solid state interaction forms and CuNPs can be synthesized from copper(II) sulfate using a low-pressure, low-temperature argon plasma. Characterization studies of the CuNPs revealed that when a metal precursor is treated under optimal experimental conditions of 80 W of argon plasma for 300 s, brown CuNPs are synthesized. However, when those same brown CuNPs are placed in Milli-Q water for a period of 10 days, oxidation occurs and green CuNPs are formed. Confirmation of the chemical identity of the CuNPs was performed by using X-ray photoelectron spectroscopy. The results reveal that the brown CuNPs are predominantly Cu0 or what we refer to as CuNPs, while the green CuNPs are a mixture of Cu0 and Cu(OH)2 NPs. Upon further characterization of both brown and green CuNPs with scanning electron microscopy (SEM), the results depict brown CuNPs with a rod-like shape and approximate dimensions of 40 nm × 160 nm, while the green CuNPs were smaller in size, with dimensions of 40-80 nm, and more of a round shape. When testing the antibacterial activity of both brown and green CuNPs, our findings demonstrate the effectiveness of both CuNPs against Escherichia coli and Staphylococcus aureus bacteria at a concentration of 17 µg/mL. The inactivation of S. aureus and E. coli 7-day-old biofilms required CuNP concentrations of 99 µg/mL. SEM images of treated 7-day-old S. aureus and E. coli biofilms depict cell membranes that are completely damaged, suggesting a physical killing mechanism. In addition, when the same concentration of CuNPs used to inactivate biofilms were tested with human fibroblasts, both brown and green CuNPs were found to be biocompatible.


Asunto(s)
Antiinfecciosos , Nanopartículas , Gases em Plasma , Humanos , Cobre/farmacología , Gases em Plasma/farmacología , Escherichia coli , Staphylococcus aureus , Antiinfecciosos/farmacología
8.
Nat Commun ; 15(1): 2549, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38514662

RESUMEN

Chemically modified nucleosi(ti)des and functional oligonucleotides (ONs, including therapeutic oligonucleotides, aptamer, nuclease, etc.) have been identified playing an essential role in the areas of medicinal chemistry, chemical biology, biotechnology, and nanotechnology. Introduction of functional groups into the nucleobases of ONs mostly relies on the laborious de novo chemical synthesis. Due to the importance of nucleosides modification and aforementioned limitations of functionalizing ONs, herein, we describe a highly efficient site-selective alkylation at the C8-position of guanines in guanosine (together with its analogues), GMP, GDP, and GTP, as well as late-stage functionalization of dinucleotides and single-strand ONs (including ssDNA and RNA) through photo-mediated Minisci reaction. Addition of catechol to assist the formation of alkyl radicals via in situ generated boronic acid catechol ester derivatives (BACED) markedly enhances the yields especially for the reaction of less stable primary alkyl radicals, and is the key to success for the post-synthetic alkylation of ONs. This method features excellent chemoselectivity, no necessity for pre-protection, wide range of substrate scope, various free radical precursors, and little strand lesion. Downstream applications in disease treatment and diagnosis, or as biochemical probes to study biological processes after linking with suitable fluorescent compounds are expected.


Asunto(s)
Nucleótidos , Oligonucleótidos , Oligonucleótidos/química , Nucleósidos , Guanina , Alquilación , Catecoles
9.
Adv Sci (Weinh) ; 11(14): e2308396, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38308105

RESUMEN

Cell-laden hydrogel fibers/tubules are one of the fundamentals of tissue engineering. They have been proven as a promising method for constructing biomimetic tissues, such as muscle fibers, nerve conduits, tendon and vessels, etc. However, current hydrogel fiber/tubule production methods have limitations in ordered cell arrangements, thus impeding the biomimetic configurations. Acoustic cell patterning is a cell manipulation method that has good biocompatibility, wide tunability, and is contact-free. However, there are few studies on acoustic cell patterning for fiber production, especially on the radial figure cell arrangements, which mimic many native tissue-like cell arrangements. Here, an acoustic cell patterning system that can be used to produce hydrogel fibers/tubules with tunable cell patterns is shown. Cells can be pre-patterned in the liquid hydrogel before being extruded as cross-linked hydrogel fibers/tubules. The radial patterns can be tuned with different complexities based on the acoustic resonances. Cell viability assays after 72 h confirm good cell viability and proliferation. Considering the biocompatibility and reliability, the present method can be further used for a variety of biomimetic fabrications.


Asunto(s)
Hidrogeles , Andamios del Tejido , Reproducibilidad de los Resultados , Ingeniería de Tejidos/métodos , Supervivencia Celular
10.
J Cereb Blood Flow Metab ; 44(3): 367-383, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37974301

RESUMEN

The crosstalk between reactive astrocytes and infiltrated immune cells plays a critical role in maintaining blood-brain barrier (BBB) integrity. However, how astrocytes interact with immune cells and the effect of their interaction on BBB integrity after hemorrhagic stroke are still unclear. By performing RNA sequencing in astrocytes that were activated by interleukin-1α (IL-1α), tumor necrosis factor α (TNFα), and complement component 1q (C1q) treatment, we found CCL5 was among the top upregulated genes. Immunostaining and western blot results demonstrated that CCL5 was increased in mice brain after hemorrhagic stroke. Flow cytometry showed that knockout of astrocytic CCL5 reduced the infiltration of CD8+ but not CD4+ T and myeloid cells into the brain (p < 0.05). In addition, knockout CCL5 in astrocytes increased tight junction-related proteins ZO-1 and Occludin expression; reduced Evans blue leakage, perforin and granzyme B expression; improved neurobehavioral outcomes in hemorrhagic stroke mice (p < 0.05), while transplantation of CD8+ T cells reversed these protective effects. Moreover, co-culture of CD8+ T cells with bEnd.3 cells induced the apoptosis of bEnd.3 cells, which was rescued by inhibiting perforin. In conclusion, our study suggests that CCL5 mediated crosstalk between astrocytes and CD8+ T cells represents an important therapeutic target for protecting BBB in stroke.


Asunto(s)
Barrera Hematoencefálica , Quimiocina CCL5 , Accidente Cerebrovascular Hemorrágico , Animales , Ratones , Astrocitos/metabolismo , Barrera Hematoencefálica/metabolismo , Linfocitos T CD8-positivos , Comunicación Celular , Células Endoteliales/metabolismo , Accidente Cerebrovascular Hemorrágico/metabolismo , Perforina/metabolismo , Perforina/farmacología , Quimiocina CCL5/metabolismo
11.
Tissue Eng Part A ; 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37930720

RESUMEN

Developing a reproducible and secure supply of customizable control tissues that standardizes for the cell type, tissue architecture, and preanalytics of interest for usage in applications including diagnostic, prognostic, and predictive assays, is critical for improving our patient care and welfare. The conventionally adopted control tissues directly obtained from patients are not ideal because they oftentimes have different amounts of normal and neoplastic elements, differing cellularity, differing architecture, and unknown preanalytics, in addition to the limited supply availability and thus associated high costs. In this study, we demonstrated a strategy to stably produce tissue-mimics for diagnostics purposes by taking advantage of the three-dimensional (3D) bioprinting technology. Specifically, we take anaplastic lymphoma kinase-positive (Alk+) lung cancer as an example, where a micropore-forming bioink laden with tumor cells was combined with digital light processing-based bioprinting for developing native-like Alk+ lung cancer tissue-mimics with both structural and functional relevancy. It is anticipated that our proposed methodology will pave new avenues for both fields of tissue diagnostics and 3D bioprinting significantly expanding their capacities, scope, and sustainability.

12.
Chem Sci ; 14(39): 10934-10943, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37829021

RESUMEN

We present an investigation into the transferability of pseudopotentials (PPs) with a nonlinear core correction (NLCC) using the Goedecker, Teter, and Hutter (GTH) protocol across a range of pure GGA, meta-GGA and hybrid functionals, and their impact on thermochemical and non-thermochemical properties. The GTH-NLCC PP for the PBE density functional demonstrates remarkable transferability to the PBE0 and ωB97X-V exchange-correlation functionals, and relative to no NLCC, improves agreement significantly for thermochemical benchmarks compared to all-electron calculations. On the other hand, the B97M-rV meta-GGA functional performs poorly with the PBE-derived GTH-NLCC PP, which is mitigated by reoptimizing the NLCC parameters for this specific functional. The findings reveal that atomization energies exhibit the greatest improvements from use of the NLCC, which thus provides an important correction needed for covalent interactions relevant to applications involving chemical reactivity. Finally we test the NLCC-GTH PPs when combined with medium-size TZV2P molecularly optimized (MOLOPT) basis sets which are typically utilized in condensed phase simulations, and show that they lead to consistently good results when compared to all-electron calculations for atomization energies, ionization potentials, barrier heights, and non-covalent interactions, but lead to somewhat larger errors for electron affinities.

13.
Appl Opt ; 62(29): 7706-7712, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37855478

RESUMEN

Surface plasmon resonance based on nanostructures has been a powerful analytical tool in rapid detection and analysis of biomolecules. However, the fabrication of nanostructure sensors, such as electron beam lithography and focused ion beam milling, has inherent defects as manufacturing cost, complex process flow, and small fabrication area. In this paper, using the transfer nanoprinting approach based on an ultrathin anodic aluminum oxide membrane, a centimeter-scale ordered periodic Ag-ZnS bilayer nanodisk on Au film with a low cost and simple process is fabricated. A surface plasmon polariton Bloch mode from nanodisk arrays is experimentally demonstrated at normal incident of light. The plasmonic platform exhibits an ideal refractive index bulk sensitivity of up to 438 nm/RIU. Furthermore, by using a polyelectrolyte bilayer with well-defined thickness, the surface sensitivity of the biosensing platform is also investigated. The large-scale plasmonic bilayer nanoparticle biosensing platform has broad application prospects in development of low-cost and high-performance biosensing chips.

14.
Obesity (Silver Spring) ; 31(12): 3043-3055, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37731225

RESUMEN

OBJECTIVE: The study's objective was to investigate the association of fat mass index (FMI) and fat-free mass index (FFMI) with all-cause mortality and cause-specific mortality in the Chinese population. METHODS: A total of 422,430 participants (48.1% men and 51.9% women) from the Taiwan MJ Cohort with an average follow-up of 9 years were included. RESULTS: The lowest (Q1) and highest (Q5) quintiles of FMI and FFMI were associated with increased all-cause mortality. Compared with those in the third quintile (Q3) group of FMI, participants in Q1 and Q5 groups of FMI had hazard ratios and 95% CI of 1.32 (1.24-1.40) and 1.13 (1.06-1.20), respectively. Similarly, compared with those in Q3 group of FFMI, people in Q1 and Q5 groups of FFMI had hazard ratios of 1.14 (1.06-1.23) and 1.16 (1.10-1.23), respectively. In the restricted cubic spline models, both FMI and FFMI showed a J-shaped association with all-cause mortality. People in Q5 group of FFMI had a hazard ratio of 0.72 (0.58-0.89) for respiratory disease. CONCLUSIONS: The mortality risk increases in those with excessively high or low FMI and FFMI, yet the associations between FMI, FFMI, and the risk of death varied across subgroups and causes of death.


Asunto(s)
Pueblo Asiatico , Composición Corporal , Mortalidad , Femenino , Humanos , Masculino , Índice de Masa Corporal , Estudios Prospectivos
15.
PNAS Nexus ; 2(8): pgad238, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37538532

RESUMEN

Cultural tightness theory, which holds that "tight" cultures have rigid norms and sanctions, provides unique insights into cultural variations. However, current theorizing has not analyzed gender differences in cultural tightness. Addressing this gap, this research shows that women are more constrained than men by norms within the same society. By recruiting 15,425 respondents, we mapped state-level gender bias in cultural tightness across the United States. Variability in gender bias in cultural tightness was associated with state-level sociopolitical factors (religion and political ideology) and gender-related threats. Gender bias in cultural tightness was positively associated with state-level gender inequality in (business and political) leadership and innovation, two major challenges faced by women professionals. Overall, this research advances cultural tightness theory and offers a cultural norms account on persistent gender inequalities in society.

16.
Diabetol Metab Syndr ; 15(1): 169, 2023 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-37574540

RESUMEN

BACKGROUND: Higher fasting plasma glucose (FPG) levels were associated with an increased risk of all-cause mortality; however, the associations between long-term FPG trajectory groups and mortality were unclear, especially among individuals with a normal FPG level at the beginning. The aims of this study were to examine the associations of FPG trajectories with the risk of mortality and identify modifiable lifestyle factors related to these trajectories. METHODS: We enrolled 50,919 individuals aged ≥ 20 years old, who were free of diabetes at baseline, in the prospective MJ cohort. All participants completed at least four FPG measurements within 6 years after enrollment and were followed until December 2011. FPG trajectories were identified by group-based trajectory modeling. We used Cox proportional hazards models to examine the associations of FPG trajectories with mortality, adjusting for age, sex, marital status, education level, occupation, smoking, drinking, physical activity, body mass index, baseline FPG, hypertension, dyslipidemia, cardiovascular disease or stroke, and cancer. Associations between baseline lifestyle factors and FPG trajectories were evaluated using multinomial logistic regression. RESULTS: We identified three FPG trajectories as stable (n = 32,481), low-increasing (n = 17,164), and high-increasing (n = 1274). Compared to the stable group, both the low-increasing and high-increasing groups had higher risks of all-cause mortality (hazard ratio (HR) = 1.18 (95% CI 0.99-1.40) and 1.52 (95% CI 1.09-2.13), respectively), especially among those with hypertension. Compared to participants with 0 to 1 healthy lifestyle factor, those with 6 healthy lifestyle factors were more likely to be in the stable group (ORlow-increasing = 0.61, 95% CI 0.51-0.73; ORhigh-increasing = 0.20, 95% CI 0.13-0.32). CONCLUSIONS: Individuals with longitudinally increasing FPG had a higher risk of mortality even if they had a normal FPG at baseline. Adopting healthy lifestyles may prevent individuals from transitioning into increasing trajectories.

17.
Synth Syst Biotechnol ; 8(3): 349-356, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37325182

RESUMEN

The bacterial trialkyl-substituted aromatic polyketides are structurally featured with the unusual aromatic core in the middle of polyketide chain such as TM-123 (1), veramycin A (2), NFAT-133 (3) and benwamycin I (4), which were discovered from Streptomyces species and demonstrated with antidiabetic and immunosuppressant activities. Though the biosynthetic pathway of 1-3 was reported as a type I polyketide synthase (PKS), the PKS assembly line was interpreted inconsistently, and it remains a mystery how the compound 3 was generated. Herein, the PKS assembly logic of 1-4 was revised by site-mutagenetic analysis of the PKS dehydratase domains. Based on gene deletion and complementation, the putative P450 monooxygenase nftE1 and metallo-beta-lactamase (MBL) fold hydrolase nftF1 were verified as essential genes for the biosynthesis of 1-4. The absence of nftE1 led to abolishment of 1-4 and accumulation of new products (5-8). Structural elucidation reveals 5-8 as the non-aromatic analogs of 1, suggesting the NftE1-catalyzed aromatic core formation. Deletion of nftF1 resulted in disappearance of 3 and 4 with the compounds 1 and 2 unaffected. As a rare MBL-fold hydrolase from type I PKSs, NftF1 potentially generates the compound 3 through two strategies: catalyze premature chain-offloading as a trans-acting thioesterase or hydrolyze the lactone-bond of compound 1 as an esterase.

18.
Aging Dis ; 14(5): 1870-1886, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37196130

RESUMEN

Optogenetics has been used to regulate astrocyte activity and modulate neuronal function after brain injury. Activated astrocytes regulate blood-brain barrier functions and are thereby involved in brain repair. However, the effect and molecular mechanism of optogenetic-activated astrocytes on the change in barrier function in ischemic stroke remain obscure. In this study, adult male GFAP-ChR2-EYFP transgenic Sprague-Dawley rats were stimulated by optogenetics at 24, 36, 48, and 60 h after photothrombotic stroke to activate ipsilateral cortical astrocytes. The effects of activated astrocytes on barrier integrity and the underlying mechanisms were explored using immunostaining, western blotting, RT-qPCR, and shRNA interference. Neurobehavioral tests were performed to evaluate therapeutic efficacy. The results demonstrated that IgG leakage, gap formation of tight junction proteins, and matrix metallopeptidase 2 expression were reduced after optogenetic activation of astrocytes (p<0.05). Moreover, photo-stimulation of astrocytes protected neurons against apoptosis and improved neurobehavioral outcomes in stroke rats compared to controls (p<0.05). Notably, interleukin-10 expression in optogenetic-activated astrocytes significantly increased after ischemic stroke in rats. Inhibition of interleukin-10 in astrocytes compromised the protective effects of optogenetic-activated astrocytes (p<0.05). We found for the first time that interleukin-10 derived from optogenetic-activated astrocytes protected blood-brain barrier integrity by decreasing the activity of matrix metallopeptidase 2 and attenuated neuronal apoptosis, which provided a novel therapeutic approach and target in the acute stage of ischemic stroke.

19.
J Alzheimers Dis ; 93(4): 1509-1520, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37212092

RESUMEN

BACKGROUND: The Cognitive role of untreated type 2 diabetes mellitus (T2DM) has been less well substantiated. OBJECTIVE: We sought to explore the prospective association of T2DM and untreated T2DM with cognitive function among middle-aged and older Chinese adults. METHODS: Data of 7,230 participants without baseline brain damage/mental retardation, or memory-related diseases in China Health and Retirement Longitudinal Study (CHARLS) from 2011- 2012 to 2015, were analyzed. Fasting plasma glucose and self-reported information on T2DM diagnosis and treatment were assessed. Participants were categorized into normoglycemia, impaired fasting glucose (IFG), and T2DM (including untreated and treated T2DM) groups. Episodic memory and executive function were assessed by modified Telephone Interview for Cognitive Status every two years. We used generalized estimating equation model to examine the association of baseline T2DM status with cognitive function in succeedingyears. RESULTS: Compared to those with normoglycemia, T2DM was associated with worse overall cognitive function after controlling for demographic variables, lifestyles, follow-up time, major clinical factors, and baseline cognitive function, although the associations were statistically non-significant (ß= -0.19, 95% CI: -0.39, 0.00). However, a significant association was mainly observed for those with untreated T2DM (ß= -0.26, 95% CI: -0.47, -0.04), especially in the domain of executive function (ß= -0.19, 95% CI: -0.35, -0.03). In general, IFG and treated T2DM individuals had similar levels of cognitive function with normoglycemia participants. CONCLUSION: Our findings supported a detrimental role of untreated T2DM on cognitive function among middle-aged and older adults. Screening and early treatment for T2DM are warranted for maintaining better cognitive function in later life.


Asunto(s)
Diabetes Mellitus Tipo 2 , Estado Prediabético , Humanos , Persona de Mediana Edad , Anciano , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Estudios Longitudinales , Estudios Prospectivos , Cognición
20.
J Chem Theory Comput ; 19(10): 2827-2841, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37156013

RESUMEN

The pseudopotential (PP) approximation is one of the most common techniques in computational chemistry. Despite its long history, the development of custom PPs has not tracked with the explosion of different density functional approximations (DFAs). As a result, the use of PPs with exchange/correlation models for which they were not developed is widespread, although this practice is known to be theoretically unsound. The extent of PP inconsistency errors (PPIEs) associated with this practice has not been systematically explored across the types of energy differences commonly evaluated in chemical applications. We evaluate PPIEs for a number of PPs and DFAs across 196 chemically relevant systems of both transition-metal and main-group elements, as represented by the W4-11, TMC34, and S22 data sets. Near the complete basis set limit, these PPs are found to cleanly approach all-electron (AE) results for noncovalent interactions but introduce root-mean-squared errors (RMSEs) upwards of 15 kcal mol-1 into predictions of covalent bond energies for a number of popular DFAs. We achieve significant improvements through the use of empirical atom- and DFA-specific PP corrections, indicating considerable systematicity of the PPIEs. The results of this work have implications for chemical modeling in both molecular contexts and for DFA design, which we discuss.

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