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2.
BMC Neurol ; 24(1): 202, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877400

RESUMO

BACKGROUND: Intratumoral hemorrhage, though less common, could be the first clinical manifestation of glioma and is detectable via MRI; however, its exact impacts on patient outcomes remain unclear and controversial. The 2021 WHO CNS 5 classification emphasised genetic and molecular features, initiating the necessity to establish the correlation between hemorrhage and molecular alterations. This study aims to determine the prevalence of intratumoral hemorrhage in glioma subtypes and identify associated molecular and clinical characteristics to improve patient management. METHODS: Integrated clinical data and imaging studies of patients who underwent surgery at the Department of Neurosurgery at Peking Union Medical College Hospital from January 2011 to January 2022 with pathological confirmation of glioma were retrospectively reviewed. Patients were divided into hemorrhage and non-hemorrhage groups based on preoperative magnetic resonance imaging. A comparison and survival analysis were conducted with the two groups. In terms of subgroup analysis, we classified patients into astrocytoma, IDH-mutant; oligodendroglioma, IDH-mutant, 1p/19q-codeleted; glioblastoma, IDH-wildtype; pediatric-type gliomas; or circumscribed glioma using integrated histological and molecular characteristics, according to WHO CNS 5 classifications. RESULTS: 457 patients were enrolled in the analysis, including 67 (14.7%) patients with intratumoral hemorrhage. The hemorrhage group was significantly older and had worse preoperative Karnofsky performance scores. The hemorrhage group had a higher occurrence of neurological impairment and a higher Ki-67 index. Molecular analysis indicated that CDKN2B, KMT5B, and PIK3CA alteration occurred more in the hemorrhage group (CDKN2B, 84.4% vs. 62.2%, p = 0.029; KMT5B, 25.0% vs. 8.9%, p = 0.029; and PIK3CA, 81.3% vs. 58.5%, p = 0.029). Survival analysis showed significantly worse prognoses for the hemorrhage group (hemorrhage 18.4 months vs. non-hemorrhage 39.1 months, p = 0.01). In subgroup analysis, the multivariate analysis showed that intra-tumoral hemorrhage is an independent risk factor only in glioblastoma, IDH-wildtype (162 cases of 457 overall, HR = 1.72, p = 0.026), but not in other types of gliomas. The molecular alteration of CDK6 (hemorrhage group p = 0.004, non-hemorrhage group p < 0.001), EGFR (hemorrhage group p = 0.003, non-hemorrhage group p = 0.001), and FGFR2 (hemorrhage group p = 0.007, non-hemorrhage group p = 0.001) was associated with shorter overall survival time in both hemorrhage and non-hemorrhage groups. CONCLUSIONS: Glioma patients with preoperative intratumoral hemorrhage had unfavorable prognoses compared to their nonhemorrhage counterparts. CDKN2B, KMT5B, and PIK3CA alterations were associated with an increased occurrence of intratumoral hemorrhage, which might be future targets for further investigation of intratumoral hemorrhage.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Masculino , Feminino , Glioma/complicações , Glioma/genética , Glioma/cirurgia , Glioma/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Prognóstico , Adulto , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Idoso , Estudos de Coortes , Adulto Jovem
3.
JCI Insight ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38889387

RESUMO

Diabetes mellitus (DM) is an independent risk factor for atrial fibrillation (AF). The mechanisms underlying DM-associated AF are unclear. AF and DM are both related to inflammation. We investigated whether DM-associated inflammation contributed to AF risk. Mice were fed with high fat diet to induce type II DM and were subjected to IL-1ß antibodies, macrophage depletion by Clodronate liposomes, a mitochondrial antioxidant (mitoTEMPO), or a cardiac ryanodine receptor (RyR2) stabilizer (S107). All tests were performed at 36-38 weeks of age. DM mice presented with increased AF inducibility, enhanced mitochondrial reactive oxygen species (mitoROS) generation, and activated innate immunity in the atria as evidenced by enhanced monocyte chemoattractant protein-1 (MCP-1) expression, macrophage infiltration, and IL-1ß levels. Signs of aberrant RyR2 Ca2+ leak were observed in the atria of DM mice. IL-1ß neutralization, macrophage depletion, mitoTEMPO, and S107 significantly ameliorated the AF vulnerability in DM mice. Atrial overexpression of MCP-1 increased AF occurrence in normal mice through the same mechanistic signaling cascade as observed in DM mice. In conclusion, macrophage-mediated IL-1ß contributed to DM-associated AF risk through mitoROS modulation of RyR2 Ca2+ leak.

4.
Phys Rev Lett ; 132(20): 201901, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38829056

RESUMO

We calculate the next-to-next-to-leading-order (NNLO) QCD radiative correction to the pion electromagnetic form factor with large momentum transfer. We explicitly verify the validity of the collinear factorization to two-loop order for this observable and obtain the respective IR-finite two-loop hard-scattering kernel in the closed form. The NNLO QCD correction turns out to be positive and significant. Incorporating this new ingredient of correction, we then make a comprehensive comparison between the finest theoretical predictions and numerous data for both space- and timelike pion form factors. Our phenomenological analysis provides a strong constraint on the second Gegenbauer moment of the pion light-cone distribution amplitude obtained from recent lattice QCD studies.

5.
Neurosci Bull ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869703

RESUMO

This study aimed to identify possible pathogenic genes in a 90-member family with a rare combination of multiple neurodegenerative disease phenotypes, which has not been depicted by the known neurodegenerative disease. We performed physical and neurological examinations with International Rating Scales to assess signs of ataxia, Parkinsonism, and cognitive function, as well as brain magnetic resonance imaging scans with seven sequences. We searched for co-segregations of abnormal repeat-expansion loci, pathogenic variants in known spinocerebellar ataxia-related genes, and novel rare mutations via whole-genome sequencing and linkage analysis. A rare co-segregating missense mutation in the CARS gene was validated by Sanger sequencing and the aminoacylation activity of mutant CARS was measured by spectrophotometric assay. This pedigree presented novel late-onset core characteristics including cerebellar ataxia, Parkinsonism, and pyramidal signs in all nine affected members. Brain magnetic resonance imaging showed cerebellar/pons atrophy, pontine-midline linear hyperintensity, decreased rCBF in the bilateral basal ganglia and cerebellar dentate nucleus, and hypo-intensities of the cerebellar dentate nuclei, basal ganglia, mesencephalic red nuclei, and substantia nigra, all of which suggested neurodegeneration. Whole-genome sequencing identified a novel pathogenic heterozygous mutation (E795V) in the CARS gene, meanwhile, exhibited none of the known repeat-expansions or point mutations in pathogenic genes. Remarkably, this CARS mutation causes a 20% decrease in aminoacylation activity to charge tRNACys with L-cysteine in protein synthesis compared with that of the wild type. All family members carrying a heterozygous mutation CARS (E795V) had the same clinical manifestations and neuropathological changes of Parkinsonism and spinocerebellar-ataxia. These findings identify novel pathogenesis of Parkinsonism-spinocerebellar ataxia and provide insights into its genetic architecture.

6.
Methods Mol Biol ; 2832: 213-222, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38869798

RESUMO

Reactive oxygen species (ROS) production is a key early defense mechanism in plants when exposed to biotic stress. Upon recognition of conserved microbe-associated molecular patterns (MAMPs) from pathogens by plant receptors, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases in the plasma membrane are activated to produce hydrogen peroxide (H2O2). This, in turn, regulates multiple signaling pathways to trigger immunity and suppress pathogen infection. Monitoring the ROS burst in plant leaves can be done within minutes of MAMPs treatment. However, there is limited research on the quantification of ROS production in plant root tissues during the activation of plant immunity. In this study, we introduce a rapid, accessible, and straightforward technique for measuring MAMPs-triggered ROS bursts in the roots of the model legume Medicago truncatula. This method will facilitate the investigation of plant root responses to biotic and abiotic stresses.


Assuntos
Medicago truncatula , Imunidade Vegetal , Raízes de Plantas , Espécies Reativas de Oxigênio , Raízes de Plantas/metabolismo , Raízes de Plantas/imunologia , Espécies Reativas de Oxigênio/metabolismo , Medicago truncatula/metabolismo , Medicago truncatula/imunologia , Peróxido de Hidrogênio/metabolismo , NADPH Oxidases/metabolismo , Moléculas com Motivos Associados a Patógenos/metabolismo , Moléculas com Motivos Associados a Patógenos/imunologia , Estresse Fisiológico , Transdução de Sinais
7.
J Ethnopharmacol ; 333: 118391, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38797377

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Parkinson's disease (PD) is the second most common neurodegenerative disorder with limited therapeutic options available. Neuroinflammation plays an important role in the occurrence and development of PD. Alkaloids extracted from Uncaria rhynchophylla (URA), have emerged as a potential neuroprotective agent because of its anti-inflammatory and anti-oxidant properties. Nevertheless, the underlying mechanism by which URA exerts neuroprotective effects in PD remains obscure. AIM OF THE STUDY: The main aim of this study was to investigate the neuroprotective effects and underlying mechanism of URA in the treatment of PD through in vivo and in vitro models, focusing on the neuroinflammation and oxidative stress pathways. MATERIALS AND METHODS: The protective effects of URA against PD were evaluated by neurobehavioral tests, immunohistochemistry, serum biochemical assays, and real-time quantitative polymerase chain reaction in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice. The role of the TLR4/NF-κB/NLRP3 pathway and the Nrf2/HO-1 pathway in URA-mediated effects was examined in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells and a microglia-neuron coculture system. RESULTS: URA significantly alleviated motor deficits and dopaminergic neurotoxicity, and reversed the abnormal secretion of inflammatory and oxidative stress factors in the serum of MPTP-induced mice. URA suppressed the gene expression of Toll-like receptor 4 (TLR4), NOD-like receptor protein 3, and cyclooxygenase 2 (COX2) in the striatum of PD mice. Further studies indicated that URA inhibited activation of the TLR4/NF-κB/NLRP3 pathway and enhanced activation of the Nrf2/HO-1 pathway, reduced reactive oxygen species (ROS) production, and reversed the secretion of inflammatory mediators in LPS-stimulated BV-2 microglial cells, thereby alleviating neuroinflammatory damage to SH-SY5Y neuronal cells. CONCLUSION: URA exerted neuroprotective effects against PD mainly by the inhibition of the TLR4/NF-κB/NLRP3 pathway and activation of the Nrf2/HO-1 antioxidant pathway, highlighting URA as a promising candidate for PD treatment.

8.
Front Med (Lausanne) ; 11: 1254467, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38695016

RESUMO

Background: Preeclampsia (PE) is a pregnancy complication defined by new onset hypertension and proteinuria or other maternal organ damage after 20 weeks of gestation. Although non-invasive prenatal testing (NIPT) has been widely used to detect fetal chromosomal abnormalities during pregnancy, its performance in combination with maternal risk factors to screen for PE has not been extensively validated. Our aim was to develop and validate classifiers that predict early- or late-onset PE using the maternal plasma cell-free DNA (cfDNA) profile and clinical risk factors. Methods: We retrospectively collected and analyzed NIPT data of 2,727 pregnant women aged 24-45 years from four hospitals in China, which had previously been used to screen for fetal aneuploidy at 12 + 0 ~ 22 + 6 weeks of gestation. According to the diagnostic criteria for PE and the time of diagnosis (34 weeks of gestation), a total of 143 early-, 580 late-onset PE samples and 2,004 healthy controls were included. The wilcoxon rank sum test was used to identify the cfDNA profile for PE prediction. The Fisher's exact test and Mann-Whitney U-test were used to compare categorical and continuous variables of clinical risk factors between PE samples and healthy controls, respectively. Machine learning methods were performed to develop and validate PE classifiers based on the cfDNA profile and clinical risk factors. Results: By using NIPT data to analyze cfDNA coverages in promoter regions, we found the cfDNA profile, which was differential cfDNA coverages in gene promoter regions between PE and healthy controls, could be used to predict early- and late-onset PE. Maternal age, body mass index, parity, past medical histories and method of conception were significantly differential between PE and healthy pregnant women. With a false positive rate of 10%, the classifiers based on the combination of the cfDNA profile and clinical risk factors predicted early- and late-onset PE in four datasets with an average accuracy of 89 and 80% and an average sensitivity of 63 and 48%, respectively. Conclusion: Incorporating cfDNA profiles in classifiers might reduce performance variations in PE models based only on clinical risk factors, potentially expanding the application of NIPT in PE screening in the future.

9.
Bioorg Chem ; 148: 107488, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797066

RESUMO

Progressive loss of dopaminergic neurons leads to the depletion of the striatal neurotransmitter dopamine, which is the main cause of Parkinson's disease (PD) motor symptoms. Simultaneous inhibition of the two key dopamine metabolic enzymes, catechol-O-methyltransferase (COMT) and monoamine oxidase B (MAO-B), could potentially be a breakthrough in achieving clinical efficacy. Representative compound C12 exhibits good COMT inhibitory activity (IC50 = 0.37 µM), metal chelation ability, and BBB permeability. Furthermore, results from in vivo biological activity evaluations indicate that C12 can improve dopamine levels and ameliorate MPTP-induced PD symptoms in mice. Preliminary in vivo and in vitro study results highlight the potential of compound C12 in PD treatment.


Assuntos
Dopamina , Inibidores da Monoaminoxidase , Monoaminoxidase , Doença de Parkinson , Animais , Camundongos , Dopamina/metabolismo , Relação Estrutura-Atividade , Monoaminoxidase/metabolismo , Estrutura Molecular , Inibidores da Monoaminoxidase/farmacologia , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/síntese química , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Catecol O-Metiltransferase/metabolismo , Camundongos Endogâmicos C57BL , Masculino , Inibidores de Catecol O-Metiltransferase/farmacologia , Inibidores de Catecol O-Metiltransferase/química , Inibidores de Catecol O-Metiltransferase/síntese química , Humanos , Relação Dose-Resposta a Droga , Antiparkinsonianos/farmacologia , Antiparkinsonianos/química , Antiparkinsonianos/síntese química , Antiparkinsonianos/uso terapêutico
10.
Artigo em Inglês | MEDLINE | ID: mdl-38743887

RESUMO

Objective: To investigate the molecular mechanism of sevoflurane affecting the development of the offspring's nervous system through the GABAAR/Sirt 1 pathway. Methods: Pregnant rats were obtained by mating females and males, and were randomly divided into 3 h sevoflurane (2.3% sevoflurane anesthesia for 3 h), 6 h sevoflurane (2.3% sevoflurane anesthesia for 6 h), Sirt-1 activator-SRT1720 (10 mg/kg SRT1720), 6 h sevoflurane+SRT1720 (10 mg/kg SRT1720) and control groups) group and control group, 31-day-old littermates were taken out and their learning and memory functions were examined by the water maze experiment; the heads were severed to remove the brains, and the kits were used to detect the levels of 5-HT and Ach in the brain tissue; the hippocampal tissues of the littermates were isolated, and neuronal damage in the hippocampal tissues was assessed by Nissen staining; neuronal apoptosis in the hippocampal tissues was detected by TUNEL staining; and GABAAR in the hippocampal tissues was detected by Western blot. GABAAR, Sirt-1, and apoptosis-related proteins (Caspase-3, BCL-2, BAX) in hippocampal tissue. Results: Compared with the control group, the 3 h sevoflurane group and the 6 h sevoflurane group neurons were arranged sparsely, the cells appeared to be swollen, the evasion latency, the apoptosis rate of neurons, the expression of Caspase-3, and BAX increased significantly, and the number of crossing the plateau, the level of 5-HT and Ach in the brain tissues, and the expression of GABAAR, Sirt-1, and BCL-2 were decreased significantly, and the differences existed between the groups (P < .5); compared with the 6 h sevoflurane group, neuronal morphological changes in the hippocampal tissue of the 6 h sevoflurane+SRT1720 group were improved, with a significant decrease in the evasion latency, neuronal apoptosis rate, expression of Caspase-3 and BAX, and a significant increase in the number of traversing platforms, brain tissue 5-HT, Ach level, GABAAR, Sirt-1, and BCL-2 expression (P < .5); compared with the SRT1720 group, the neurons in the 6 h sevoflurane + SRT1720 group were sparsely arranged, with a significant increase in evasion latency, neuronal apoptosis rate, caspase-3, BAX expression, and a significant decrease in the number of traversing platforms, brain tissue 5-HT, Ach level, GABAAR, Sirt-1, and BCL-2 expression (P < .5 ). Conclusion: Sevoflurane can affect the neurological development of rat offspring, which may be related to the inhibition of Sirt-1 expression.

11.
Zool Res ; 45(3): 648-662, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38766747

RESUMO

Mild traumatic brain injury (mTBI)-induced post-traumatic headache (PTH) is a pressing public health concern and leading cause of disability worldwide. Although PTH is often accompanied by neurological disorders, the exact underlying mechanism remains largely unknown. Identifying potential biomarkers may prompt the diagnosis and development of effective treatments for mTBI-induced PTH. In this study, a mouse model of mTBI-induced PTH was established to investigate its effects on cerebral structure and function during short-term recovery. Results indicated that mice with mTBI-induced PTH exhibited balance deficits during the early post-injury stage. Metabolic kinetics revealed that variations in neurotransmitters were most prominent in the cerebellum, temporal lobe/cortex, and hippocampal regions during the early stages of PTH. Additionally, variations in brain functional activities and connectivity were further detected in the early stage of PTH, particularly in the cerebellum and temporal cortex, suggesting that these regions play central roles in the mechanism underlying PTH. Moreover, our results suggested that GABA and glutamate may serve as potential diagnostic or prognostic biomarkers for PTH. Future studies should explore the specific neural circuits involved in the regulation of PTH by the cerebellum and temporal cortex, with these two regions potentially utilized as targets for non-invasive stimulation in future clinical treatment.


Assuntos
Modelos Animais de Doenças , Cefaleia Pós-Traumática , Animais , Camundongos , Cefaleia Pós-Traumática/etiologia , Cefaleia Pós-Traumática/fisiopatologia , Masculino , Encéfalo/metabolismo , Encéfalo/patologia , Concussão Encefálica/complicações , Concussão Encefálica/fisiopatologia , Camundongos Endogâmicos C57BL
12.
Artigo em Inglês | MEDLINE | ID: mdl-38724232

RESUMO

BACKGROUND: Intranasal transplantation of ANGE-S003 human neural stem cells showed therapeutic effects and were safe in preclinical models of Parkinson's disease (PD). We investigated the safety and tolerability of this treatment in patients with PD and whether these effects would be apparent in a clinical trial. METHODS: This was a 12-month, single-centre, open-label, dose-escalation phase 1 study of 18 patients with advanced PD assigned to four-time intranasal transplantation of 1 of 3 doses: 1.5 million, 5 million or 15 million of ANGE-S003 human neural stem cells to evaluate their safety and efficacy. RESULTS: 7 patients experienced a total of 14 adverse events in the 12 months of follow-up after treatment. There were no serious adverse events related to ANGE-S003. Safety testing disclosed no safety concerns. Brain MRI revealed no mass formation. In 16 patients who had 12-month Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) data, significant improvement of MDS-UPDRS total score was observed at all time points (p<0.001), starting with month 3 and sustained till month 12. The most substantial improvement was seen at month 6 with a mean reduction of 19.9 points (95% CI, 9.6 to 30.3; p<0.001). There was no association between improvement in clinical outcome measures and cell dose levels. CONCLUSIONS: Treatment with ANGE-S003 is feasible, generally safe and well tolerated, associated with functional improvement in clinical outcomes with peak efficacy achieved at month 6. Intranasal transplantation of neural stem cells represents a new avenue for the treatment of PD, and a larger, longer-term, randomised, controlled phase 2 trial is warranted for further investigation.

13.
J Hazard Mater ; 474: 134757, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38820759

RESUMO

To address the serious environmental pollution problems of toxic heavy metal ions in water bodies, a novel fluorescent composite hydrogel N, P-CDs@CMC/PEI with a bio-based polymer matrix of carboxylmethyl cellulose (CMC), polyethylenimine (PEI) as a second interpenetrating network and N, P-doped carbon dots (N, P-CDs) as a fluorescent probe was prepared for simultaneous detection and capture of HMIs by a facile and simple one-step approach. The morphology, chemical structure, swelling ratio, mechanical strength and fluorescence property of these composite hydrogels were studied through varied characterization methods. The composite hydrogel showed sensitive and selective fluorescence response with Hg(II) and Fe(III) and the according LOD values were 0.48 and 0.27 mg L-1, respectively. The relationship between the types of the adsorbent, pH value, HMIs concentration and temperature on the adsorption capacity of these composite hydrogels were studied. The pseudo-second-order model and Langmuir model were applicable to explain the adsorption process of CPH2 for Hg(II) and Cr(VI). The maximum calculated adsorption capacities for the above targeted HMIs by Langmuir model were 846.7 and 289.5 mg g-1, respectively. Coexisting inorganic salts and organic acids in low concentration had little effects on Hg(II) and Cr(VI) removal and the composite hydrogel showed good recyclability and stability for Hg(II) and Cr(VI) removal after four cycles. The electrostatic attraction and coordination covalent bonds were responsible for the adsorption process.

14.
Eur J Med Chem ; 272: 116463, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704944

RESUMO

Butyrylcholinesterase (BChE) has attracted wide interest as a promising target in Alzheimer's disease (AD) investigation. BChE is considered to play a compensable role of hydrolyzing acetylcholine (ACh), and its positive correlation with ß-amyloid (Aß) deposition also promotes disease progression. Herein, we uncovered a selective potent BChE inhibitor S21-1011 (eqBChE IC50 = 0.059 ± 0.006 µM, hBChE IC50 = 0.162 ± 0.069 µM), which presented satisfactory druggability and therapeutic efficacy in AD models. In pharmacokinetics (PK) studies, S21-1011 showed excellent blood-brain barrier (BBB) permeability, metabolism stability and high oral-bioavailability. In pharmacodynamic (PD) studies, it protected neural cells from toxicity and inflammation stimulation in vitro. Besides, it also exerted anti-inflammatory effect and alleviated cognitive impairment in mice models induced by lipopolysaccharides (LPS) and Aß. Generally, this compound has been confirmed to function as a neuroprotector and cognition improver in various AD pathology-like models. Therefore, S21-1011, a novel potent BChE inhibitor, could be considered as a potential anti-AD candidate worthy of more profound investigation.


Assuntos
Doença de Alzheimer , Butirilcolinesterase , Inibidores da Colinesterase , Quinolinas , Butirilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/síntese química , Camundongos , Humanos , Relação Estrutura-Atividade , Quinolinas/química , Quinolinas/farmacologia , Quinolinas/síntese química , Descoberta de Drogas , Estrutura Molecular , Masculino , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Relação Dose-Resposta a Droga , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/síntese química , Piperazinas/farmacologia , Piperazinas/química , Piperazinas/síntese química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/síntese química , Inflamação/tratamento farmacológico , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos
15.
RSC Adv ; 14(24): 16951-16959, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38812961

RESUMO

Yellow wine lees, a by-product produced while brewing yellow wine, can be a helpful biomass resource through pyrolysis. However, there have been very few studies on the pyrolysis of yellow wine lees. The kinetics and mechanism of pyrolysis in yellow wine lees were explored through an extensive study of their chemical and elemental composition. The pyrolysis mechanism of yellow wine lees was further studied using thermogravimetric analysis (TGA) from 30 °C to 900 °C. The TG/DTG analysis showed that yellow wine lees thermally decomposed mainly between 121 °C and 500 °C. The maximum decomposition was observed between 218 °C and 326 °C, with a clear peak at 298 °C. Upon analyzing the 3D-FTIR results, the gas phase products at this stage primarily included inorganic molecules like CO2, H2O, and CH4, along with organic compounds such as esters, alcohols, phenols, amines, ethers, aldehydes, ketones, and acids. The Maillard reaction and ketosis decarboxylation primarily occurred in proteins (amino acids) and carbohydrates. The pyrolysis kinetics of yellow wine lees were analyzed utilizing the distributed activation energy model (DAEM). The results of DAEM were simultaneously verified using the Flynn-Wall-Ozawa (FWO) method. The findings indicated that the pyrolysis of yellow wine lees conforms to the assumptions of infinite parallel reactions and activation energy distribution. As the conversion rate increased during pyrolysis, the activation energy of yellow wine lees initially increased to 210-220 kJ mol-1, then stabilized at 190-200 kJ mol-1 and rapidly decreased to approximately 100 kJ mol-1. This study offers a theoretical basis for the application of yellow wine lees using pyrolysis.

16.
Curr Biol ; 34(8): 1705-1717.e6, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38574729

RESUMO

Plants establish symbiotic associations with arbuscular mycorrhizal fungi (AMF) to facilitate nutrient uptake, particularly in nutrient-limited conditions. This partnership is rooted in the plant's ability to recognize fungal signaling molecules, such as chitooligosaccharides (chitin) and lipo-chitooligosaccharides. In the legume Medicago truncatula, chitooligosaccharides trigger both symbiotic and immune responses via the same lysin-motif-receptor-like kinases (LysM-RLKs), notably CERK1 and LYR4. The nature of plant-fungal engagement is opposite according to the outcomes of immunity or symbiosis signaling, and as such, discrimination is necessary, which is challenged by the dual roles of CERK1/LYR4 in both processes. Here, we describe a LysM-RLK, LYK8, that is functionally redundant with CERK1 for mycorrhizal colonization but is not involved in chitooligosaccharides-induced immunity. Genetic mutation of both LYK8 and CERK1 blocks chitooligosaccharides-triggered symbiosis signaling, as well as mycorrhizal colonization, but shows no further impact on immunity signaling triggered by chitooligosaccharides, compared with the mutation of CERK1 alone. LYK8 interacts with CERK1 and forms a receptor complex that appears essential for chitooligosaccharides activation of symbiosis signaling, with the lyk8/cerk1 double mutant recapitulating the impact of mutations in the symbiosis signaling pathway. We conclude that this novel receptor complex allows chitooligosaccharides activation specifically of symbiosis signaling and helps the plant to differentiate between activation of these opposing signaling processes.


Assuntos
Quitina , Quitosana , Medicago truncatula , Micorrizas , Proteínas de Plantas , Simbiose , Micorrizas/fisiologia , Quitina/metabolismo , Medicago truncatula/microbiologia , Medicago truncatula/metabolismo , Medicago truncatula/imunologia , Medicago truncatula/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Imunidade Vegetal , Oligossacarídeos/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo
17.
ACS Omega ; 9(16): 17760-17783, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38680370

RESUMO

Natural nano-minerals (NNMs) are minerals that are derived from nature with a size of less than 100 nm in at least one dimension in size. NNMs have a number of excellent properties due to their unique nanostructure and have been applied in various fields in recent years. They are rising stars in various disciplines, such as materials, biomedicine, and chemistry, taking advantage of their huge surface area, multiple active sites, excellent adsorption capacity, large quantity, low cost, and nontoxicity, etc. To provide a more comprehensive overview of NNMs and the biomedical applications of NNMs-based nanocomposites, this review classifies NNMs into three types by dimension, lists the structure and properties of typical NNMs, and illustrates their biomedical applications. Furthermore, a novel concept of natural nanomineral medical materials (NNMMs) is proposed, focusing on the medical value of NNMs. In addition, this review attempts to address the current challenges and delineate future directions for the advancement of NNMs. With the deepening of biomedical applications, it is believed that NNMMMs will inevitably play an important role in the field of human health and contribute to its promotion.

18.
Int J Biol Macromol ; 268(Pt 2): 131789, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677708

RESUMO

Polysaccharides have gained attention as valuable supplements and natural medicinal resources, particularly for their anti-tumor properties. Their low toxicity and potent anti-tumor effects make them promising candidates for cancer prevention and treatment. The tumor microenvironment is crucial in tumor development and offers potential avenues for novel cancer therapies. Research indicates that polysaccharides can positively influence the tumor microenvironment. However, the structural complexity of most anti-tumor polysaccharides, often heteropolysaccharides, poses challenges for structural analysis. To enhance their pharmacological activity, researchers have modified the structure and properties of natural polysaccharides based on structure-activity relationships, and they have discovered that many polysaccharides exhibit significantly enhanced anti-tumor activity after chemical modification. This article reviews recent strategies for targeting the tumor microenvironment with polysaccharides and briefly discusses the structure-activity relationships of anti-tumor polysaccharides. It also summarises the main chemical modification methods of polysaccharides and discusses the impact of chemical modifications on the anti-tumor activity of polysaccharides. The review aims to lay a theoretical foundation for the development of anti-tumor polysaccharides and their derivatives.


Assuntos
Neoplasias , Polissacarídeos , Microambiente Tumoral , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico
19.
Anal Bioanal Chem ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602542

RESUMO

Natural attapulgite (ATP) is a promising substitute for existing artificial nanozymes due to its intrinsic enzymatic activity. However, the active center of ATP's inherent enzymatic activity has not yet been revealed, which limits its further design and activity optimization. Studying the active center of mineral materials can be extremely challenging due to their complexity. Here, we demonstrated that Fe is the primary element in ATP responsible for peroxidase (POD)-like activity through theoretical speculation and experimental verification. More importantly, we found that the ratio of Fe2+/Fe3+ is responsible for the district POD-like activity of ATP from different regions with the same Fe content. Additionally, three facile strategies, including grinding, heat treatment, and acid treatment, were demonstrated to increase the relative Fe content and thus optimize the POD-like activity of ATP. Finally, ATP was used to detect the concentration of H2O2, enabling the detection of low concentrations (0.11-1.76 mM) of H2O2. This study serves as a novel reference for the future design and performance optimization of nanozymes that are based on ATP and clay minerals.

20.
Nat Commun ; 15(1): 2917, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575562

RESUMO

VISTA, an inhibitory myeloid-T-cell checkpoint, holds promise as a target for cancer immunotherapy. However, its effective targeting has been impeded by issues such as rapid clearance and cytokine release syndrome observed with previous VISTA antibodies. Here we demonstrate that SNS-101, a newly developed pH-selective VISTA antibody, addresses these challenges. Structural and biochemical analyses confirmed the pH-selectivity and unique epitope targeted by SNS-101. These properties confer favorable pharmacokinetic and safety profiles on SNS-101. In syngeneic tumor models utilizing human VISTA knock-in mice, SNS-101 shows in vivo efficacy when combined with a PD-1 inhibitor, modulates cytokine and chemokine signaling, and alters the tumor microenvironment. In summary, SNS-101, currently in Phase I clinical trials, emerges as a promising therapeutic biologic for a wide range of patients whose cancer is refractory to current immunotherapy regimens.


Assuntos
Neoplasias , Receptor de Morte Celular Programada 1 , Humanos , Camundongos , Animais , Antígenos B7 , Anticorpos , Neoplasias/tratamento farmacológico , Imunoterapia , Concentração de Íons de Hidrogênio , Microambiente Tumoral
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