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1.
Adv Sci (Weinh) ; : e2401877, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639403

RESUMO

In recent decades, there has been a significant increase in the application of single-molecule electrical analysis platforms in studying proteins and peptides. These advanced analysis methods have the potential for deep investigation of enzymatic working mechanisms and accurate monitoring of dynamic changes in protein configurations, which are often challenging to achieve in ensemble measurements. In this work, the prominent research progress in peptide and protein-related studies are surveyed using electronic devices with single-molecule/single-event sensitivity, including single-molecule junctions, single-molecule field-effect transistors, and nanopores. In particular, the successful commercial application of nanopores in DNA sequencing has made it one of the most promising techniques in protein sequencing at the single-molecule level. From single peptides to protein complexes, the correlation between their electrical characteristics, structures, and biological functions is gradually being established. This enables to distinguish different molecular configurations of these biomacromolecules through real-time electrical monitoring of their life activities, significantly improving the understanding of the mechanisms underlying various life processes.

2.
J Glob Health ; 14: 04017, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38635810

RESUMO

Background: Previous studies on the effect of global warming on the global burden of disease have mainly focussed on the impact of high temperatures, thereby providing limited evidence of the effect of lower temperatures. Methods: We adopted a three-stage analysis approach using data from the Global Burden of Disease 2019 study. First, we explored the global burden of disease attributable to low temperatures, examining variations by gender, age, cause, region, and country. Second, we analysed temporal trends in low-temperature-related disease burdens from 1990 to 2019 by meta-regression. Finally, we fitted a mixed-effects meta-regression model to explore the effect modification of country-level characteristics. Results: In 2019, low temperatures were responsible for 2.92% of global deaths and 1.03% of disability-adjusted life years (DALYs), corresponding to a death rate of 21.36 (95% uncertainty interval (UI) = 18.26, 24.73) and a DALY rate of 335 (95% UI = 280, 399) per 100 000 population. Most of the deaths (85.12%) and DALYs (94.38%) attributable to low temperatures were associated with ischaemic heart disease, stroke, and chronic obstructive pulmonary disease. In the last three decades, we observed an upward trend for the annual number of attributable deaths (P < 0.001) and a downward trend for the rates of death (P < 0.001) and DALYs (P < 0.001). The disease burden associated with low temperatures varied considerably among regions and countries, with higher burdens observed in regions with middle or high-middle socio-demographic indices, as well as countries with higher gross domestic product per capita and a larger proportion of ageing population. Conclusions: Our findings emphasise the significance of raising public awareness and prioritising policies to protect global population health from the adverse effects of low temperatures, even in the face of global warming. Particular efforts should be targeted towards individuals with underlying diseases (e.g. cardiovascular diseases) and vulnerable countries or regions (e.g. Central Asia and central Europe).


Assuntos
Carga Global da Doença , Doença Pulmonar Obstrutiva Crônica , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Temperatura , Efeitos Psicossociais da Doença , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Saúde Global , Fatores de Risco
3.
RSC Adv ; 14(15): 10397-10408, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38567324

RESUMO

Sodium-aluminate-silicate-hydrate (NASH) gel, as the primary reaction product stimulated by alkali in silica-aluminum-rich minerals, influences the mechanical and durability properties of geopolymers. In erosion environments, NASH demonstrates superior compressive strength and erosion resistance compared to hydration products of ordinary Portland cement. However, the underlying erosion resistance mechanism of NASH under such conditions remains unclear. Therefore, this study employs molecular dynamics research methodology to investigate the alteration in performance and deterioration mechanism of NASH in erosive environments. The findings reveal that in Na2SO4 solution, the infiltration of H2O molecules and Na+ ions into the three-dimensional mesh structure of NASH results in slight expansion and reduced tensile strength. Although H2O intrusion induces hydrolysis of the three-dimensional skeleton, the adsorption sites within NASH possess the capability to capture externally introduced Na+ ions. During tensile loading, Na+ ions can interact with reactive oxygen species produced through stretching or H2O molecule-induced decomposition of the internal framework, facilitating the repair of fractured structures. Consequently, this process partially alleviates tensile rupture, modifies the fracture damage mode, enhances overall toughness, and improves resistance against sulfate attack.

4.
Cell Metab ; 36(4): 725-744, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38569470

RESUMO

Postbiotics, which comprise inanimate microorganisms or their constituents, have recently gained significant attention for their potential health benefits. Extensive research on postbiotics has uncovered many beneficial effects on hosts, including antioxidant activity, immunomodulatory effects, gut microbiota modulation, and enhancement of epithelial barrier function. Although these features resemble those of probiotics, the stability and safety of postbiotics make them an appealing alternative. In this review, we provide a comprehensive summary of the latest research on postbiotics, emphasizing their positive impacts on both human and animal health. As our understanding of the influence of postbiotics on living organisms continues to grow, their application in clinical and nutritional settings, as well as animal husbandry, is expected to expand. Moreover, by substituting postbiotics for antibiotics, we can promote health and productivity while minimizing adverse effects. This alternative approach holds immense potential for improving health outcomes and revolutionizing the food and animal products industries.


Assuntos
Microbioma Gastrointestinal , Probióticos , Animais , Humanos , Promoção da Saúde , Estado Nutricional , Antibacterianos , Probióticos/farmacologia , Probióticos/uso terapêutico
5.
JACC Clin Electrophysiol ; 10(4): 685-694, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38658060

RESUMO

BACKGROUND: Reconnection after mitral isthmus (MI) block with radiofrequency ablation is common. OBJECTIVES: The aim of this study was to investigate the effects of ethanol infusion in the vein of Marshall (EIVOM) on acute reconnection after MI bidirectional block. METHODS: Patients with persistent atrial fibrillation who were scheduled to receive radiofrequency ablation for the first time were randomly assigned to the radiofrequency catheter ablation (RFCA) group (n = 44) or the EIVOM group (n = 45). The RFCA group's strategy was bilateral pulmonary vein ablation and linear ablation; in the EIVOM group, EIVOM was performed first. The primary endpoint was acute reconnection 30 minutes after MI bidirectional block. RESULTS: A total of 89 patients (average age 62.9 years; 57.3% male) were enrolled. The average duration for persistent atrial fibrillation was 2.3 years. Before observation, all patients in the EIVOM group achieved MI bidirectional block (45 of 45 [100%]), compared with 84.1% (37 of 44) in the RFCA group. After the observation, 3 cases of MI reconnection occurred in the EIVOM group and 13 cases in the RFCA group (6.7% vs 35.1%; P < 0.05). After additional ablation, the final MI block rates in the EIVOM and RFCA groups were 97.8% (44 of 45) and 72.7% (32 of 44), respectively. During a 1-year follow-up, 8 of 45 patients who underwent EIVOM had recurrent atrial fibrillation, compared with 14 of 44 in the RFCA group (17.8% vs 31.8%; P < 0.01). CONCLUSIONS: EIVOM can reduce acute reconnection after MI bidirectional block and significantly increase first-pass MI block.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Valva Mitral , Veias Pulmonares , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Idoso , Valva Mitral/cirurgia , Veias Pulmonares/cirurgia , Etanol/administração & dosagem , Recidiva , Resultado do Tratamento
6.
Cell Signal ; 119: 111169, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599440

RESUMO

Cardiac resident macrophages (CRMs) are essential in maintaining the balance of the immune homeostasis in the heart. One of the main factors in the progression of cardiovascular diseases, such as myocarditis, myocardial infarction(MI), and heart failure(HF), is the imbalance in the regulatory mechanisms of CRMs. Recent studies have reported novel heterogeneity and spatiotemporal complexity of CRMs, and their role in maintaining cardiac immune homeostasis and treating cardiovascular diseases. In this review, we focus on the functions of CRMs, including immune surveillance, immune phagocytosis, and immune metabolism, and explore the impact of CRM's homeostasis imbalance on cardiac injury and cardiac repair. We also discuss the therapeutic approaches linked to CRMs. The immunomodulatory strategies targeting CRMs may be a therapeutic approach for the treatment of cardiovascular disease.

7.
Lancet ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38588689

RESUMO

BACKGROUND: Mental disorders are the leading global cause of health burden among adolescents. However, prevalence data for mental disorders among adolescents in low-income and middle-income countries are scarce with often limited generalisability. This study aimed to generate nationally representative prevalence estimates for mental disorders in adolescents in Kenya, Indonesia, and Viet Nam. METHODS: As part of the National Adolescent Mental Health Surveys (NAMHS), a multinational cross-sectional study, nationally representative household surveys were conducted in Kenya, Indonesia, and Viet Nam between March and December, 2021. Adolescents aged 10-17 years and their primary caregiver were interviewed from households selected randomly according to sampling frames specifically designed to elicit nationally representative results. Six mental disorders (social phobia, generalised anxiety disorder, major depressive disorder, post-traumatic stress disorder, conduct disorder, and attention-deficit hyperactivity disorder) were assessed with the Diagnostic Interview Schedule for Children, Version 5. Suicidal behaviours and self-harm in the past 12 months were also assessed. Prevalence in the past 12 months and past 4 weeks was calculated for each mental disorder and collectively for any mental disorder (ie, of the six mental disorders assessed). Prevalence of suicidal behaviours (ie, ideation, planning, and attempt) and self-harm in the past 12 months was calculated, along with adjusted odds ratios (aORs) to show the association with prevalence of any mental disorder in the past 12 months. Inverse probability weighting was applied to generate national estimates with corresponding 95% CIs. FINDINGS: Final samples consisted of 5155 households (ie, adolescent and primary caregiver pairs) from Kenya, 5664 households from Indonesia, and 5996 households from Viet Nam. In Kenya, 2416 (46·9%) adolescents were male and 2739 (53·1%) were female; in Indonesia, 2803 (49·5%) adolescents were male and 2861 (50·5%) were female; and in Viet Nam, 3151 (52·5%) were male and 2845 (47·4%) were female. Prevalence of any mental disorder in the past 12 months was 12·1% (95% CI 10·9-13·5) in Kenya, 5·5% (4·3-6·9) in Indonesia, and 3·3% (2·7-4·1) in Viet Nam. Prevalence in the past 4 weeks was 9·4% (8·3-10·6) in Kenya, 4·4% (3·4-5·6) in Indonesia, and 2·7% (2·2-3·3) in Viet Nam. The prevalence of suicidal behaviours in the past 12 months was low in all three countries, with suicide ideation ranging from 1·4% in Indonesia (1·0-2·0) and Viet Nam (1·0-1·9) to 4·6% (3·9-5·3) in Kenya, suicide planning ranging from 0·4% in Indonesia (0·3-0·8) and Viet Nam (0·2-0·6) to 2·4% (1·9-2·9) in Kenya, and suicide attempts ranging from 0·2% in Indonesia (0·1-0·4) and Viet Nam (0·1-0·3) to 1·0% (0·7-1·4) in Kenya. The prevalence of self-harm in the past 12 months was also low in all three countries, ranging from 0·9% (0·6-1·3) in Indonesia to 1·2% (0·9-1·7) in Kenya. However, the prevalence of suicidal behaviours and self-harm in the past 12 months was significantly higher among those with any mental disorder in the past 12 months than those without (eg, aORs for suicidal ideation ranged from 7·1 [3·1-15·9] in Indonesia to 14·7 [7·5-28·6] in Viet Nam). INTERPRETATION: NAMHS provides the first national adolescent mental disorders prevalence estimates for Kenya, Indonesia, and Viet Nam. These data can inform mental health and broader health policies in low-income and middle-income countries. FUNDING: The University of Queensland in America (TUQIA) through support from Pivotal Ventures, a Melinda French Gates company.

8.
J Mater Chem B ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591180

RESUMO

Cyaonoside A (CyA), derived from the natural Chinese medicine, Cyathula officinalis Kuan, which was for a long time used to treat knee injuries and relieve joint pain in traditional Chinese medicine, showed an unclear mechanism for protecting cartilage. In addition, CyA was poorly hydrosoluble and incapable of being injected directly into the joint cavity, which limited its clinical application. This study reveals that CyA resisted IL-1ß-mediated chondrogenic inflammation and apoptosis. Next, transcriptome sequencing is used to explore the potential mechanisms underlying CyA regulation of MSC chondrogenic differentiation. Based on these findings, CyA-loaded composite hydrogel microspheres (HLC) were developed and they possessed satisfactory loading efficiency, a suitable degradation rate and good biocompatibility. HLC increased chondrogenic anabolic gene (Acan, COL2A, and SOX9) expression, while downregulating the expression of the catabolic marker MMP13 in vitro. In the osteoarthritis mouse model, HLC demonstrated promising therapeutic capabilities by protecting the integrity of articular cartilage. In conclusion, this study provides insights into the regulatory mechanisms of CyA for chondrocytes and proposes a composite hydrogel microsphere-based advanced therapeutic strategy for osteoarthritis.

9.
Am J Otolaryngol ; 45(4): 104274, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38593552

RESUMO

PURPOSE: To investigate the effects of oropharyngeal exercise on continuous positive airway pressure (CPAP) compliance in patients with moderate to severe obstructive sleep apnea over a period of 6 months. MATERIALS AND METHODS: This study was conducted as a prospective, observational, and interventional investigation. A total of 70 patients with moderate to severe obstructive sleep apnea were randomly assigned to either the oropharyngeal exercise group (n = 44) or the sham-therapy group (n = 26). The compliance of the enrolled patients with CPAP therapy was assessed at baseline, 3-month follow-up and 6-month follow-up. Objective sleep data, questionnaire and CPAP use time were collected over a half-year period (i.e., baseline, 6 months, and 12 months). RESULTS: The study found that the average use time of CPAP within one month was significantly longer in the oropharyngeal exercises group compared to the sham-therapy group at the 3-month assessment (5.5 ± 1.2 vs 4.8 ± 1.3 h per night; p=0.030), and much significantly longer at 6-months assessment (6.0 ± 1.4 vs 4.9 ± 1.3 h per night; p=0.001). Furthermore, the average use time of CPAP increased over time, with the oropharyngeal exercises group exhibiting a more pronounced growth from baseline to the six-month follow-up (4.8 ± 1.0 h per night to 6.0 ± 1.3 h per night, p < 0.001) compared to the sham-therapy group (4.8 ± 1.3 h per night to 4.9 ± 1.3 h per night, p=0.952). Additionally, the oropharyngeal exercise group demonstrated an improvement in the Epworth sleepiness scale compared to the sham-therapy group at the 3-month follow-up (6.0 ± 2.0 vs 8.8 ± 3.2; p < 0.001), as well as decreased significantly at 6-month follow-up (p = 0.032). CONCLUSIONS: CPAP adherence can be improved with oropharyngeal exercises therapy among moderate to severe OSA patients. Notably, the average duration of CPAP usage and reduction in daytime sleepiness were maintained even after six months of oropharyngeal exercise therapy.

10.
Nat Prod Res ; : 1-8, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597194

RESUMO

Sixteen triterpenoid saponins were isolated from the roots of Bupleurum scorzonerifolium Willd., including a new triterpenoid saponin and new natural saponin that was characterised by NMR for the first time, along with 14 known triterpenoid saponins. The structures of the compounds were established by 1D and 2D NMR spectroscopy, HR-ESI-MS, and comparison with the literature. The cytotoxic activity of the compounds against 4T1 cells was determined using the CCK8 method. Compounds 9 and 6 showed the strongest cytotoxic activity with IC50 values of 2.75 ± 0.86 and 3.78 ± 0.50 µM, respectively. Compounds 2-5 and 8 showed potent cytotoxic activity. Compounds 14 and 16 showed moderate cytotoxicity.

11.
J Nanobiotechnology ; 22(1): 153, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580995

RESUMO

BACKGROUND: Osteoporosis is characterized by an imbalance in bone homeostasis, resulting in the excessive dissolution of bone minerals due to the acidified microenvironment mediated by overactive osteoclasts. Oroxylin A (ORO), a natural flavonoid, has shown potential in reversing osteoporosis by inhibiting osteoclast-mediated bone resorption. The limited water solubility and lack of targeting specificity hinder the effective accumulation of Oroxylin A within the pathological environment of osteoporosis. RESULTS: Osteoclasts' microenvironment-responsive nanoparticles are prepared by incorporating Oroxylin A with amorphous calcium carbonate (ACC) and coated with glutamic acid hexapeptide-modified phospholipids, aiming at reinforcing the drug delivery efficiency as well as therapeutic effect. The obtained smart nanoparticles, coined as OAPLG, could instantly neutralize acid and release Oroxylin A in the extracellular microenvironment of osteoclasts. The combination of Oroxylin A and ACC synergistically inhibits osteoclast formation and activity, leading to a significant reversal of systemic bone loss in the ovariectomized mice model. CONCLUSION: The work highlights an intelligent nanoplatform based on ACC for spatiotemporally controlled release of lipophilic drugs, and illustrates prominent therapeutic promise against osteoporosis.


Assuntos
Reabsorção Óssea , Osteoporose , Camundongos , Animais , Osteoclastos , Nanomedicina , Osteoporose/tratamento farmacológico , Reabsorção Óssea/tratamento farmacológico , Osso e Ossos/patologia , Diferenciação Celular
12.
Nat Prod Res ; : 1-8, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587148

RESUMO

Two novel phenylpropanoid amides, namely huomarenamide A (1) and huomarenamide B (2), along with twelve known compounds (3-14), were isolated from the seeds of Cannabis sativa L. The structures with absolute configurations of new compounds were unequivocally determined by spectroscopic analyses and the ECD method. The identification of the known compounds was based on a comparison of their 1D NMR data with literature references. All compounds were assessed for cytotoxic activity against LN229 cells, revealing that compounds 2, 13, and 14 exhibited significant cytotoxicity with IC50 values ranging from 9.02 to 21.26 µM.

13.
PeerJ ; 12: e16887, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38436019

RESUMO

Groupitizing is a well-established strategy in numerosity perception that enhances speed and sensory precision. Building on the ATOM theory, Anobile proposed the sensorimotor numerosity system, which posits a strong link between number and action. Previous studies using motor adaptation technology have shown that high-frequency motor adaptation leads to underestimation of numerosity perception, while low-frequency adaptation leads to overestimation. However, the impact of motor adaptation on groupitizing, and whether visual motion adaptation produces similar effects, remain unclear. In this study, we investigate the persistence of the advantage of groupitizing after motor adaptation and explore the effects of visual motion adaptation. Surprisingly, our findings reveal that proprioceptive motor adaptation weakens the advantage of groupitizing, indicating a robust effect of motor adaptation even when groupitizing is employed. Moreover, we observe a bidirectional relationship, as groupitizing also weakens the adaptation effect. These results highlight the complex interplay between motor adaptation and groupitizing in numerosity perception. Furthermore, our study provides evidence that visual motion adaptation also has an adaptation effect, but does not fully replicate the effects of proprioceptive motor adaptation on groupitizing. In conclusion, our research underscores the importance of groupitizing as a valuable strategy in numerosity perception, and sheds light on the influence of motion adaptation on this strategy.


Assuntos
Propriocepção , Tecnologia , Movimento (Física) , Percepção
14.
Bioact Mater ; 36: 157-167, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38463554

RESUMO

Much effort has been devoted to improving treatment efficiency for osteosarcoma (OS). However, most current approaches result in poor therapeutic responses, thus indicating the need for the development of other therapeutic options. This study developed a multifunctional nanoparticle, PDA-MOF-E-M, an aggregation of OS targeting, programmed death targeting, and near-infrared (NIR)-aided targeting. At the same time, a multifunctional nanoparticle that utilises Fe-MOFs to create a cellular iron-rich environment and erastin as a ferroptosis inducer while ensuring targeted delivery to OS cells through cell membrane encapsulation is presented. The combination of PDA-MOF-E-M and PTT increased intracellular ROS and LPO levels and induced ferroptosis-related protein expression. A PDA-based PTT combined with erastin showed significant synergistic therapeutic improvement in the anti-tumour efficiency of the nanoparticle in vitro and vivo. The multifunctional nanoparticle efficiently prevents the osteoclasia progression of OS xenograft bone tumors in vivo. Finally, this study provides guidance and a point of reference for clinical approaches to treating OS.

15.
Adv Sci (Weinh) ; : e2307921, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477181

RESUMO

Additive manufacturing (AM) is widely recognized as a versatile tool for achieving complex geometries and customized functionalities in designed materials. However, the challenge lies in selecting an appropriate AM method that simultaneously realizes desired microstructures and macroscopic geometrical designs in a single sample. This study presents a direct ink writing method for 3D printing intricate, high-fidelity macroscopic cellulose aerogel forms. The resulting aerogels exhibit tunable anisotropic mechanical and thermal characteristics by incorporating fibers of different length scales into the hydrogel inks. The alignment of nanofibers significantly enhances mechanical strength and thermal resistance, leading to higher thermal conductivities in the longitudinal direction (65 mW m-1  K-1 ) compared to the transverse direction (24 mW m-1  K-1 ). Moreover, the rehydration of printed cellulose aerogels for biomedical applications preserves their high surface area (≈300 m2  g-1 ) while significantly improving mechanical properties in the transverse direction. These printed cellulose aerogels demonstrate excellent cellular viability (>90% for NIH/3T3 fibroblasts) and exhibit robust antibacterial activity through in situ-grown silver nanoparticles.

16.
Cell Mol Life Sci ; 81(1): 130, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472355

RESUMO

ALKBH1 is a typical demethylase of nucleic acids, which is correlated with multiple types of biological processes and human diseases. Recent studies are focused on the demethylation of ALKBH1, but little is known about its non-demethylase function. Here, we demonstrate that ALKBH1 regulates the glycolysis process through HIF-1α signaling in a demethylase-independent manner. We observed that depletion of ALKBH1 inhibits glycolysis flux and extracellular acidification, which is attributable to reduced HIF-1α protein levels, and it can be rescued by reintroducing HIF-1α. Mechanistically, ALKBH1 knockdown enhances chaperone-mediated autophagy (CMA)-mediated HIF-1α degradation by facilitating the interaction between HIF-1α and LAMP2A. Furthermore, we identify that ALKBH1 competitively binds to the OST48, resulting in compromised structural integrity of oligosaccharyltransferase (OST) complex and subsequent defective N-glycosylation of LAMPs, particularly LAMP2A. Abnormal glycosylation of LAMP2A disrupts lysosomal homeostasis and hinders the efficient degradation of HIF-1α through CMA. Moreover, NGI-1, a small-molecule inhibitor that selectively targets the OST complex, could inhibit the glycosylation of LAMPs caused by ALKBH1 silencing, leading to impaired CMA activity and disruption of lysosomal homeostasis. In conclusion, we have revealed a non-demethylation role of ALKBH1 in regulating N-glycosylation of LAMPs by interacting with OST subunits and CMA-mediated degradation of HIF-1α.


Assuntos
Autofagia , Transdução de Sinais , Humanos , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Glicosilação , Glicólise , Homólogo AlkB 1 da Histona H2a Dioxigenase/metabolismo
17.
Phys Chem Chem Phys ; 26(14): 10579-10588, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38505975

RESUMO

Graphene oxide (GO) as a nano-reinforcing material has received extensive attention in cement composite materials. This paper employed molecular dynamics to simulate the friction process of calcium silicate hydrate (CSH) particles in the presence of double-sided and single-sided GCOOH (graphene oxide with a -COOH functional group, covering 10% of the surface). The investigation uncovered the lubricating effects of bifacial and unifacial GCOOH on the CSH interface. The findings indicate that the interfacial friction among CSH particles follows the sequence of double-sided GCOOH > pure CSH > single-sided GCOOH. In the double-sided GCOOH system, a greater external force is needed on the opposing side to alter the interaction with water molecules, calcium ions, and silica-oxygen tetrahedra, thereby enhancing friction. In contrast, the majority of the carboxyl groups on the single-sided GCOOH surface are strongly adsorbed onto the CSH surface, facilitating the entry of additional water molecules into the interlayer. Conversely, the unmodified side of the GCOOH has lower interactions with water molecules, hence improving its lubricating properties.

18.
Am J Hypertens ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459938

RESUMO

The effectiveness of Renal Denervation (RDN) in reducing blood pressure and systemic sympathetic activity in hypertensive patients has been established. However, the underlying central mechanism remains unknown. This study aimed to investigate the role of RDN in regulating cardiovascular function via the central Renin-Angiotensin System (RAS) pathway. Ten-week-old Spontaneously Hypertensive Rats (SHR) were subjected to Selective Afferent Renal Denervation (ADN) using capsaicin solution. We hypothesized that ADN would effectively reduce blood pressure and rebalance the RAS component of PVN in SHR. The experimental results show that ADN group exhibited significantly lower blood pressure, reduced systemic sympathetic activity, decreased chronic neuronal activation marker C-FOS expression in the paraventricular nucleus of hypothalamus (PVN), and improved arterial baroreflex function, compared with the Sham group. Furthermore, ACE and AT1 protein expression was reduced while ACE2 and MAS protein expression was increased in the PVN of SHR after ADN. These findings suggest that RDN may exert these beneficial effects through modulating the central RAS pathway.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38530347

RESUMO

A Gram-stain-negative, non-endospore-forming, motile, short rod-shaped strain, designated SYSU G07232T, was isolated from a hot spring microbial mat, sampled from Rehai National Park, Tengchong, Yunnan Province, south-western China. Strain SYSU G07232T grew at 25-50 °C (optimum, 37 °C), at pH 5.5-9.0 (optimum, pH 6.0) and tolerated NaCl concentrations up to 1.0 % (w/v). Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain SYSU G07232T showed closest genetic affinity with Chelatococcus daeguensis K106T. The genomic features and taxonomic status of this strain were determined through whole-genome sequencing and a polyphasic approach. The predominant quinone of this strain was Q-10. Major cellular fatty acids comprised C19 : 0 cyclo ω8c and summed feature 8. The whole-genome length of strain SYSU G07232T was 4.02 Mbp, and the DNA G+C content was 69.26 mol%. The average nucleotide identity (ANIm ≤84.85 % and ANIb ≤76.08  %) and digital DNA-DNA hybridization (≤ 21.9 %) values between strain SYSU G07232T and the reference species were lower than the threshold values recommended for distinguishing novel prokaryotic species. Thus, based on the provided phenotypic, phylogenetic, and genetic data, it is proposed that strain SYSU G07232T (=KCTC 8141T=GDMCC 1.4178T) be designated as representing a novel species within the genus Chelatococcus, named Chelatococcus albus sp. nov.


Assuntos
Beijerinckiaceae , Fontes Termais , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , China , Ácidos Graxos/química , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Bactérias
20.
Artigo em Inglês | MEDLINE | ID: mdl-38501848

RESUMO

Ventricular diverticula are saccule-like structures formed by the protrusion of the ventricular myocardium from the endocardial surface towards the free wall. Most diverticula are muscular structures, and patients usually have no obvious clinical symptoms. However, diverticula may contribute to arrhythmogenesis due to localized myocardial structural disturbances. Right ventricular apical diverticulum (RVAD) is very rare, and we report a case of highly symptomatic accelerated idioventricular rhythm (AIVR) originating from the RVAD that underwent intracardiac echocardiography (ICE)-guided catheter ablation with no recurrence during follow-up.

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