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2.
Zool Res ; 45(6): 1209-1220, 2024 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-39382080

RESUMEN

High-altitude and marine mammals inhabit distinct ecosystems but share a common challenge: hypoxia. To survive in low-oxygen environments, these species have evolved similar phenotypic pulmonary adaptations, characterized by a high density of elastic fibers. In this study, we explored the molecular mechanisms underlying these adaptations, focusing on pulmonary fibrosis and hypoxia tolerance through comparative genomics and convergent evolution analyses. We observed significant expansions and contractions in certain gene families across both high-altitude and marine mammals, closely associated with processes involved in pulmonary fibrosis. Notably, members of the keratin gene family, such as KRT17 and KRT14, appear to be associated with the development of the dense elastic fiber phenotype observed in the lungs of hypoxia-tolerant mammals. Through selection pressure and amino acid substitution analyses, we identified multiple genes exhibiting convergent accelerated evolution, positive selection, and amino acid substitution in these species, associated with adaptation to hypoxic environments. Specifically, the convergent evolution of ZFP36L1, FN1, and NEDD9 was found to contribute to the high density of elastic fibers in the lungs of both high-altitude and marine mammals, facilitating their hypoxia tolerance. Additionally, we identified convergent amino acid substitutions and gene loss events associated with sperm development, differentiation, and spermatogenesis, such as amino acid substitutions in SLC26A3 and pseudogenization of CFAP47, as confirmed by PCR. These genetic alterations may be linked to changes in the reproductive capabilities of these animals. Overall, this study offers novel perspectives on the genetic and molecular adaptations of high-altitude and marine mammals to hypoxic environments, with a particular emphasis on pulmonary fibrosis.


Asunto(s)
Adaptación Fisiológica , Altitud , Hipoxia , Fibrosis Pulmonar , Animales , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/veterinaria , Adaptación Fisiológica/genética , Hipoxia/genética , Mamíferos/genética , Evolución Biológica , Evolución Molecular , Filogenia
3.
J Integr Med ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39358063

RESUMEN

BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) infection posed a huge threat and burden to public healthcare in late 2022. Non-drug measures of traditional Chinese medicine (TCM), such as acupuncture, cupping and moxibustion, are commonly used as adjuncts in China to help in severe cases, but their effects remain unclear. OBJECTIVES: To observe the clinical effect of TCM non-drug measures in improving respiratory function and symptoms among patients with severe COVID-19. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: This study was designed as a multicenter, assessor-blind, randomized controlled trial. Hospitalized patients with COVID-19 were randomly assigned to the treatment or control group. The treatment group received individualized TCM non-drug measures in combination with prone position ventilation, while the control group received prone position ventilation only for 5 consecutive days. MAIN OUTCOME MEASURES: The primary outcome measures were the percentage of patients with improved oxygen saturation (SpO2) at the end of the 5-day intervention, as well as changes of patients' respiratory rates. The secondary outcome measures included changes in SpO2 and total score on the self-made respiratory symptom scale. The improvement rate, defined as a 3-day consecutive increase in SpO2, the duration of prone positioning, and adverse events were recorded as well. RESULTS: Among the 198 patients included in the intention-to-treat analysis, 159 (80.3%) completed all assessments on day 5, and 39 (19.7%) patients withdrew from the study. At the end of the intervention, 71 (91%) patients in the treatment group had SpO2 above 93%, while 61 (75.3%) in the control group reached this level. The proportion of participant with improved SpO2 was significantly greater in the intervention group (mean difference [MD] = 15.7; 95% confidence interval [CI]: 4.4, 27.1; P = 0.008). Compared to the baseline, with daily treatment there were significant daily decreases in respiratory rates in both groups, but no statistical differences between groups were found (all P ≥ 0.05). Compared to the control group, the respiratory-related symptoms score was lower among patients in the treatment group (MD = -1.7; 95%CI: -2.8, -0.5; P = 0.008) after day 3 of treatment. A gradual decrease in the total scores of both groups was also observed. Thirty-one adverse events occurred during the intervention, and 2 patients were transferred to the intensive care unit due to deterioration of their illness. CONCLUSION: TCM non-drug measures combined with prone positioning can effectively treat patients with severe COVID-19. The combined therapy significantly increased SpO2 and improved symptom scores compared to prone positioning alone, thus improving the patients' respiratory function to help them recover. However, the improvement rate did not differ between the two groups. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2300068319). Please cite this article as: Yin X, Jin Z, Li F, Huang L, Hu YM, Zhu BC, Wang ZQ, Li XY, Li JP, Lao LX, Mi YQ, Xu SF. Effectiveness and safety of adjunctive non-drug measures in improving respiratory symptoms among patients with severe COVID-19: A multicenter randomized controlled trial. J Integr Med. 2024; Epub ahead of print.

4.
Tissue Cell ; 91: 102554, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39316936

RESUMEN

Liver fibrosis is characterized by an excessive reparative response to various etiological factors, with the activated hepatic stellate cells (aHSCs) leading to extracellular matrix (ECM) accumulation. Senescence is a stable growth arrest, and the senescence of aHSCs is associated with the degradation of ECM and the regression of hepatic fibrosis, making it a promising approach for managing hepatic fibrosis. The role and specific mechanisms by which V-Type Proton ATPase Subunit G 3 (ATP6V1G3) influences senescence in activated HSCs during liver fibrosis remain unclear. Our preliminary results reveal upregulation of ATP6V1G3 in both human fibrotic livers and murine liver fibrosis models. Additionally, ATP6V1G3 inhibition induced senescence in aHSCs in vitro. Moreover, suppressing Notch1 reversed the senescence caused by ATP6V1G3 inhibition in HSCs. Thus, targeting ATP6V1G3, which appears to drive HSCs senescence through the Notch1 pathway, emerges as a potential therapeutic strategy for hepatic fibrosis.

5.
World J Diabetes ; 15(9): 1932-1941, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39280178

RESUMEN

BACKGROUND: Diabetes mellitus type 2 (T2DM) is formed by defective insulin secretion with the addition of peripheral tissue resistance of insulin action. It has been affecting over 400 million people all over the world. AIM: To explore the pathogenesis of T2DM and to develop and implement new prevention and treatment strategies for T2DM. METHODS: Receiver operating characteristic (ROC) curve analysis was used to conduct diagnostic markers. The expression level of genes was determined by reverse transcription-PCR as well as Western blot. Cell proliferation assays were performed by cell counting kit-8 (CCK-8) tests. At last, T2DM mice underwent Roux-en-Y gastric bypass surgery. RESULTS: We found that NPAS2 was significantly up-regulated in islet ß cell apoptosis of T2DM. The ROC curve revealed that NPAS2 was capable of accurately diagnosing T2DM. NPAS2 overexpression did increase the level of KANK1. In addition, the CCK-8 test revealed knocking down NPAS2 and KANK1 increased the proliferation of MIN6 cells. At last, we found that gastric bypass may treat type 2 diabetes by down-regulating NPAS2 and KANK1. CONCLUSION: This study demonstrated that NPAS2 induced ß cell dysfunction by regulating KANK1 expression in type 2 diabetes, and it may be an underlying therapy target of T2DM.

6.
Nat Commun ; 15(1): 7922, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256428

RESUMEN

The absence of a comprehensive understanding of the neural basis of spontaneous pain limits the development of therapeutic strategies targeting this primary complaint of patients with chronic pain. Here we report a distinct neuronal ensemble within the prelimbic cortex which processes signals related to spontaneous pain in rats with chronic inflammatory pain. This neuronal ensemble specifically encodes spontaneous pain-related behaviors, independently of other locomotive and evoked behaviors. Activation of this neuronal ensemble elicits marked spontaneous pain-like behaviors and enhances nociceptive responses, whereas prolonged silencing of its activities alleviates spontaneous pain and promotes overall recovery from inflammatory pain. Notably, afferents from the primary somatosensory cortex and infralimbic cortex bidirectionally modulate the activities of the spontaneous pain-responsive prelimbic cortex neuronal ensemble and pain behaviors. These findings reveal the cortical basis of spontaneous pain at the neuronal level, highlighting a distinct neuronal ensemble within the prelimbic cortex and its associated pain-regulatory brain networks.


Asunto(s)
Inflamación , Neuronas , Ratas Sprague-Dawley , Corteza Somatosensorial , Animales , Neuronas/metabolismo , Neuronas/fisiología , Masculino , Ratas , Corteza Somatosensorial/fisiopatología , Dolor/fisiopatología , Conducta Animal , Modelos Animales de Enfermedad , Dolor Crónico/fisiopatología , Corteza Prefrontal/fisiopatología
7.
bioRxiv ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39345440

RESUMEN

Background: Heart failure with preserved ejection fraction (HFpEF) is a significant public health concern with limited treatment options. Dysregulated nitric oxide-mediated signaling has been implicated in HFpEF pathophysiology, however, little is known about the role of endogenous hydrogen sulfide (H2S). Objectives: This study evaluated H2S bioavailability in patients and two animal models of cardiometabolic HFpEF and assessed the impact of H2S on HFpEF severity through alterations in endogenous H2S production and pharmacological supplementation. Methods: HFpEF patients and two rodent models of HFpEF ("two-hit" L-NAME + HFD mouse and ZSF1 obese rat) were evaluated for H2S bioavailability. Two cohorts of two-hit mice were investigated for changes in HFpEF pathophysiology: (1) endothelial cell cystathionine-γ-lyase (EC-CSE) knockout; (2) H2S donor, JK-1, supplementation. Results: H2S levels were significantly reduced (i.e., 81%) in human HFpEF patients and in both preclinical HFpEF models. This depletion was associated with reduced CSE expression and activity, and increased SQR expression. Genetic knockout of H2S -generating enzyme, CSE, worsened HFpEF characteristics, including elevated E/e' ratio and LVEDP, impaired aortic vasorelaxation and increased mortality. Pharmacologic H2S supplementation restored H2S bioavailability, improved diastolic function and attenuated cardiac fibrosis corroborating an improved HFpEF phenotype. Conclusions: H2S deficiency is evident in HFpEF patients and conserved across multiple HFpEF models. Increasing H2S bioavailability improved cardiovascular function, while knockout of endogenous H2S production exacerbated HFpEF pathology and mortality. These results suggest H2S dysregulation contributes to HFpEF and increasing H2S bioavailability may represent a novel therapeutic strategy for HFpEF. Highlights: H2S deficiency is evident in both human HFpEF patients and two clinically relevant models.Reduced H2S production by CSE and increased metabolism by SQR impair H2S bioavailability in HFpEF.Pharmacological H2S supplementation improves diastolic function and reduces cardiac fibrosis in HFpEF models.Targeting H2S dysregulation presents a novel therapeutic strategy for managing HFpEF.

8.
Circ Res ; 135(8): 806-821, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39229723

RESUMEN

BACKGROUND: Cardiac hypertrophy and its associated remodeling are among the leading causes of heart failure. Lysine crotonylation is a recently discovered posttranslational modification whose role in cardiac hypertrophy remains largely unknown. NAE1 (NEDD8 [neural precursor cell expressed developmentally downregulated protein 8]-activating enzyme E1 regulatory subunit) is mainly involved in the neddylation modification of protein targets. However, the function of crotonylated NAE1 has not been defined. This study aims to elucidate the effects and mechanisms of NAE1 crotonylation on cardiac hypertrophy. METHODS: Crotonylation levels were detected in both human and mouse subjects with cardiac hypertrophy through immunoprecipitation and Western blot assays. Tandem mass tag (TMT)-labeled quantitative lysine crotonylome analysis was performed to identify the crotonylated proteins in a mouse cardiac hypertrophic model induced by transverse aortic constriction. We generated NAE1 knock-in mice carrying a crotonylation-defective K238R (lysine to arginine mutation at site 238) mutation (NAE1 K238R) and NAE1 knock-in mice expressing a crotonylation-mimicking K238Q (lysine to glutamine mutation at site 238) mutation (NAE1 K238Q) to assess the functional role of crotonylation of NAE1 at K238 in pathological cardiac hypertrophy. Furthermore, we combined coimmunoprecipitation, mass spectrometry, and dot blot analysis that was followed by multiple molecular biological methodologies to identify the target GSN (gelsolin) and corresponding molecular events contributing to the function of NAE1 K238 (lysine residue at site 238) crotonylation. RESULTS: The crotonylation level of NAE1 was increased in mice and patients with cardiac hypertrophy. Quantitative crotonylomics analysis revealed that K238 was the main crotonylation site of NAE1. Loss of K238 crotonylation in NAE1 K238R knock-in mice attenuated cardiac hypertrophy and restored the heart function, while hypercrotonylation mimic in NAE1 K238Q knock-in mice significantly enhanced transverse aortic constriction-induced pathological hypertrophic response, leading to impaired cardiac structure and function. The recombinant adenoviral vector carrying NAE1 K238R mutant attenuated, while the K238Q mutant aggravated Ang II (angiotensin II)-induced hypertrophy. Mechanistically, we identified GSN as a direct target of NAE1. K238 crotonylation of NAE1 promoted GSN neddylation and, thus, enhanced its protein stability and expression. NAE1 crotonylation-dependent increase of GSN promoted actin-severing activity, which resulted in adverse cytoskeletal remodeling and progression of pathological hypertrophy. CONCLUSIONS: Our findings provide new insights into the previously unrecognized role of crotonylation on nonhistone proteins during cardiac hypertrophy. We found that K238 crotonylation of NAE1 plays an essential role in mediating cardiac hypertrophy through GSN neddylation, which provides potential novel therapeutic targets for pathological hypertrophy and cardiac remodeling.


Asunto(s)
Cardiomegalia , Animales , Humanos , Cardiomegalia/metabolismo , Cardiomegalia/patología , Cardiomegalia/genética , Ratones , Masculino , Procesamiento Proteico-Postraduccional , Ratones Endogámicos C57BL , Enzimas Activadoras de Ubiquitina/metabolismo , Enzimas Activadoras de Ubiquitina/genética , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Ratones Transgénicos , Proteína NEDD8/metabolismo , Proteína NEDD8/genética , Células HEK293
9.
Biomed Environ Sci ; 37(8): 876-886, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39198252

RESUMEN

Objective: The study aimed to investigate the impact of rare earth elements (REEs) exposure on pregnancy outcomes of in vitro fertilization-embryo transfer (IVF-ET) by analyzing samples from spouses. Methods: A total of 141 couples were included. Blood and follicular fluid from the wives and semen plasma from the husbands, were analyzed for REEs using inductively coupled plasma mass spectrometry (ICP-MS). Spearman's correlation coefficients and the Mann-Whitney U test were used to assess correlations and compare REE concentrations among three types of samples, respectively. Logistic models were utilized to estimate the individual REE effect on IVF-ET outcomes, while BKMR and WQS models explored the mixture of REE interaction effects on IVF-ET outcomes. Results: Higher La concentration in semen (median 0.089 ng/mL, P = 0.03) was associated with a lower fertilization rate. However, this effect was not observed after artificial selection intervention through intracytoplasmic sperm injection (ICSI) ( P = 0.27). In semen, the REEs mixture did not exhibit any significant association with clinical pregnancy. Conclusion: Our study revealed a potential association between high La exposure in semen and a decline in fertilization rate, but not clinical pregnancy rate. This is the first to report REEs concentrations in follicular fluid with La, Ce, Pr, and Nd found at significantly lower concentrations than in serum, suggesting that these four REEs may not accumulate in the female reproductive system. However, at the current exposure levels, mixed REEs exposure did not exhibit reproductive toxicity.


Asunto(s)
Transferencia de Embrión , Fertilización In Vitro , Metales de Tierras Raras , Humanos , Femenino , Adulto , Embarazo , Metales de Tierras Raras/análisis , Masculino , Beijing , Semen/química , Resultado del Embarazo , Líquido Folicular/química
10.
J Anxiety Disord ; 106: 102912, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39094317

RESUMEN

Neuromodulation treatments are novel interventions for post-traumatic stress disorder (PTSD), but their comparative effects at treatment endpoint and follow-up and the influence of moderators remain unclear. We included randomized controlled trials (RCTs) that explored neuromodulation, both as monotherapy and in combination, for treating patients with PTSD. 21 RCTs with 981 PTSD patients were included. The neuromodulation treatment was classified into nine protocols, including subtypes of transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), cervical vagal nerve stimulation (VNS), and trigeminal nerve stimulation (TNS). This Bayesian network meta-analysis demonstrated that (1) dual-tDCS (SMD = -1.30), high-frequency repetitive TMS (HF-rTMS) (SMD = -0.97), intermittent theta burst stimulation (iTBS) (SMD = -0.93), and low-frequency repetitive TMS (LF-rTMS) (SMD = -0.76) were associated with significant reductions in PTSD symptoms at the treatment endpoint, but these effects were not significant at follow-up; (2) no difference was found between any active treatment with sham controls; (3) regarding co-morbid additions, synchronized TMS (sTMS) was significantly associated with reductions of depression symptoms at treatment endpoint (SMD = -1.80) and dual-tDCS was associated with reductions in anxiety symptoms at follow-up (SMD = -1.70). Findings suggested dual-tDCS, HF-rTMS, iTBS, and LF-rTMS were effective for reducing PTSD symptoms, while their sustained efficacy was limited.


Asunto(s)
Metaanálisis en Red , Trastornos por Estrés Postraumático , Estimulación Magnética Transcraneal , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Trastornos por Estrés Postraumático/terapia , Estimulación Transcraneal de Corriente Directa/métodos , Estimulación Magnética Transcraneal/métodos , Resultado del Tratamiento , Estimulación del Nervio Vago/métodos
11.
Int J Biol Macromol ; 278(Pt 3): 134969, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39179060

RESUMEN

The reactions involving enzymes are significantly influenced by various environmental factors. Clarity of how the activity and structure of proteases impact their function is crucial for more efficient application of enzymes as a tool. The impact of temperature, pH, and ionic strength on changes in protease activity, secondary structure, and protein conformation during enzymatic hydrolysis were investigated in this study. The enzymatic activity and secondary structure of acid-base protease were found to undergo significant modifications under different physical conditions, as demonstrated by UV spectrophotometry and FTIR spectroscopy analysis. Specifically, variations in α-helix and ß-fold content were observed to correlate with changes in enzyme activity. Molecular simulation analysis revealed that physical conditions have varying effects on the protease, particularly influencing enzyme activity and secondary structure. Evaluation of the proteases indicated alterations in both enzyme activity and structure. This treatment selectively hydrolyzed ß-lactoglobulin and reduced sensitization. These findings offer novel perspectives on the functionalities and regulatory mechanisms of proteases, as well as potential industrial applications.


Asunto(s)
Péptido Hidrolasas , Estructura Secundaria de Proteína , Hidrólisis , Péptido Hidrolasas/química , Péptido Hidrolasas/metabolismo , Concentración de Iones de Hidrógeno , Temperatura , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Concentración Osmolar , Simulación de Dinámica Molecular
12.
Opt Lett ; 49(17): 4891-4894, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39207990

RESUMEN

We experimentally demonstrate a liquid crystal (LC)-integrated EIT metasurface for active THz polarization conversion and asymmetric transmission. By controlling the LC orientation under static magnetic field anchoring and an adjustable electric field, the device realizes the active control from the OFF state to the ON state, corresponding to the orthogonal polarization excitation modes of the EIT metasurface. Furthermore, based on the different polarization responses at forward and backward incidences, we achieve asymmetric transmission at the EIT peak and two nearby resonances, with its isolation actively manipulated by the external electric field. This study on dynamic polarization conversion and asymmetric transmission by a LC-integrated metasurface offers a promising route for active THz devices, applicable to THz communication, switching, and sensing systems.

14.
Nat Prod Res ; : 1-6, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39148321

RESUMEN

Piperine, a natural amide isolated from the genus of Piper, serves as a pharmacophore in medicinal chemistry. In this study, we synthesised and evaluated 18 novel piperine-acylhydrazone hybrids (4a-4r) for their antiproliferative activities in vitro. The structures of these hybrids were validated using 1H,13C NMR, and HR-ESI-MS data. Furthermore, we screened all synthesised compounds for their antiproliferative activities against three human cancer cell lines: FaDu (laryngeal carcinoma cells), HepG2 (hepatoblastoma carcinoma cells), and MGC803 (gastric carcinoma cells). Among them, compound 4o exhibited significantly inhibitory activities against FaDu, HepG2, and MGC803 with IC50 values of 13.85 ± 0.19, 11.02 ± 1.45, and 13.47 ± 3.43 µM, respectively, which was approximately two-fold lower than the positive control cisplatin. These findings suggest that compound 4o has the potential to be promising leads for the design of anti-cancer drugs.

15.
Zhonghua Nan Ke Xue ; 30(3): 254-260, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-39177393

RESUMEN

Gossypol is a natural product extracted from cotton seeds, roots and stems, once used as a male contraceptive and later found with an anti-tumor effect. Recent studies show that it has an antiviral effect after structurally modified. This review focuses on the status quo of present studies on the effects of gossypol and its derivatives in anti-reproduction and anti-PCa, with an introduction of the application of the new compounds obtained from structural modification of gossypol in the treatment of PCa.


Asunto(s)
Anticonceptivos Masculinos , Gosipol , Gosipol/farmacología , Gosipol/análogos & derivados , Masculino , Humanos , Anticonceptivos Masculinos/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Reproducción/efectos de los fármacos , Animales
16.
Neuroscience ; 553: 172-184, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-38964454

RESUMEN

Genetic variants in genes encoding subunits of the γ-aminobutyric acid-A receptor (GABAAR) have been found to cause neurodevelopmental disorders and epileptic encephalopathy. In a patient with epilepsy and developmental delay, a de novo heterozygous missense mutation c.671 T > C (p.F224S) was discovered in the GABRB2 gene, which encodes the ß2 subunit of GABAAR. Based on previous studies on GABRB2 variants, this new GABRB2 variant (F224S) would be pathogenic. To confirm and investigate the effects of this GABRB2 mutation on GABAAR channel function, we conducted transient expression experiments using GABAAR subunits in HEK293T cells. The GABAARs containing mutant ß2 (F224S) subunit showed poor trafficking to the cell membrane, while the expression and distribution of the normal α1 and γ2 subunits were unaffected. Furthermore, the peak current amplitude of the GABAAR containing the ß2 (F224S) subunit was significantly smaller compared to the wild type GABAAR. We propose that GABRB2 variant F224S is pathogenic and GABAARs containing this ß2 mutant reduce response to GABA under physiological conditions, which could potentially disrupt the excitation/inhibition balance in the brain, leading to epilepsy.


Asunto(s)
Discapacidades del Desarrollo , Epilepsia , Mutación Missense , Receptores de GABA-A , Humanos , Receptores de GABA-A/genética , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/fisiopatología , Células HEK293 , Epilepsia/genética , Epilepsia/fisiopatología , Masculino , Femenino
18.
Materials (Basel) ; 17(13)2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38998397

RESUMEN

Generally, rejuvenators are used to supply missing components of aged asphalt, reverse the aging process, and are widely used in asphalt maintenance and recycling. However, compared with traditional rejuvenators, bio-oil rejuvenators are environmentally friendly, economical and efficient. This study looks into the effect of the three different bio-oils, namely sunflower oil, soybean oil, and palm oil, on the physical properties, rheological properties and chemical components of aged asphalt at different dosages. The asphalt physical properties and Dynamic Shear Rheological (DSR) test results show that with the increase in bio-oil, the physical properties and rheological properties of rejuvenated asphalt are close to those of virgin asphalt, but the high-temperature rutting resistance needs to be further improved. The results of Fourier Transform Infrared Spectroscopy (FTIR) show that the carbonyl and sulfoxide indices of rejuvenated asphalt are much lower than those of aged asphalt. Moreover, the rejuvenation efficiency of aged asphalt mixed with sunflower oil is better than that with soybean oil and palm oil at the same dosage.

19.
Int J Biol Macromol ; 276(Pt 1): 133732, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39002919

RESUMEN

γ-aminobutyric acid (GABA) plays an important role in anti-anxiety by inhibiting neurotransmitter in the central nervous system (CNS) of mammals, which is generated in the germinating seeds. The key enzymes activity of GABA metabolism pathway and nutrients content in hemp seeds during germination were studied after treated with ultrasound and CaCl2. The mechanism of exogenous stress on key enzymes in GABA metabolism pathway was investigated by molecular dynamics simulation. The results showed that ultrasonic combined with 1.5 mmol·L-1CaCl2 significantly increased the activities of glutamate decarboxylase (GAD) and GABA transaminase (GABA-T) in seeds, and promoted the conversion of glutamate to GABA, resulting in the decrease of glutamate content and the accumulation of GABA. Molecular dynamics simulations revealed that Ca2+ environment enhanced the activity of GAD and GABA-T enzymes by altering their secondary structure, exposing their hydrophobic residues. Ultrasound, germination and CaCl2 stress improved the nutritional value of hemp seeds.


Asunto(s)
Cloruro de Calcio , Cannabis , Germinación , Semillas , Cannabis/metabolismo , Cannabis/química , Germinación/efectos de los fármacos , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Cloruro de Calcio/farmacología , Cloruro de Calcio/química , Ondas Ultrasónicas , Ácido gamma-Aminobutírico/metabolismo , Glutamato Descarboxilasa/metabolismo , Simulación de Dinámica Molecular , 4-Aminobutirato Transaminasa/metabolismo , 4-Aminobutirato Transaminasa/química
20.
Proc Natl Acad Sci U S A ; 121(29): e2323040121, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38985761

RESUMEN

Stomata in leaves regulate gas (carbon dioxide and water vapor) exchange and water transpiration between plants and the atmosphere. SLow Anion Channel 1 (SLAC1) mediates anion efflux from guard cells and plays a crucial role in controlling stomatal aperture. It serves as a central hub for multiple signaling pathways in response to environmental stimuli, with its activity regulated through phosphorylation via various plant protein kinases. However, the molecular mechanism underlying SLAC1 phosphoactivation has remained elusive. Through a combination of protein sequence analyses, AlphaFold-based modeling and electrophysiological studies, we unveiled that the highly conserved motifs on the N- and C-terminal segments of SLAC1 form a cytosolic regulatory domain (CRD) that interacts with the transmembrane domain(TMD), thereby maintaining the channel in an autoinhibited state. Mutations in these conserved motifs destabilize the CRD, releasing autoinhibition in SLAC1 and enabling its transition into an activated state. Our further studies demonstrated that SLAC1 activation undergoes an autoinhibition-release process and subsequent structural changes in the pore helices. These findings provide mechanistic insights into the activation mechanism of SLAC1 and shed light on understanding how SLAC1 controls stomatal closure in response to environmental stimuli.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Estomas de Plantas , Transducción de Señal , Fosforilación , Estomas de Plantas/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Dominios Proteicos , Mutación
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