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1.
Nat Commun ; 15(1): 7804, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39242543

RESUMEN

Protein kinases are key signaling nodes that regulate fundamental biological and disease processes. Illuminating kinase signaling from multiple angles can provide deeper insights into disease mechanisms and improve therapeutic targeting. While fluorescent biosensors are powerful tools for visualizing live-cell kinase activity dynamics in real time, new molecular tools are needed that enable recording of transient signaling activities for post hoc analysis and targeted manipulation. Here, we develop a light-gated kinase activity coupled transcriptional integrator (KINACT) that converts dynamic kinase signals into "permanent" fluorescent marks. KINACT enables robust monitoring of kinase activity across scales, accurately recording subcellular PKA activity, highlighting PKA activity distribution in 3D cultures, and identifying PKA activators and inhibitors in high-throughput screens. We further leverage the ability of KINACT to drive signaling effector expression to allow feedback manipulation of the balance of GαsR201C-induced PKA and ERK activation and dissect the mechanisms of oncogenic G protein signaling.


Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico , Transducción de Señal , Humanos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Células HEK293 , Luz , Técnicas Biosensibles/métodos
2.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(9): 974-981, 2024.
Artículo en Chino | MEDLINE | ID: mdl-39267514

RESUMEN

OBJECTIVES: To investigate the effects and molecular mechanisms of inhibition of the Ras homolog gene (Rho)/Rho-associated coiled-coil forming protein kinase (ROCK) pathway on the proliferation and migration of airway smooth muscle cells involving myocardin (MYOCD). METHODS: Human airway smooth muscle cells were infected with the adenoviral vector Ad-ZsGreen-shRNA-hROCK1 in vitro. The cells were randomly divided into four groups: ROCK1 gene silencing control (shNC) group, shNC + arachidonic acid (AA, Rho/ROCK pathway activator) group, ROCK1 gene silencing (shROCK1) group, and shROCK1 + AA group (n=3 each). Quantitative real-time polymerase chain reaction and Western blot were used to detect the expression levels of ROCK1 and MYOCD mRNA and protein. ELISA was employed to measure the levels of globular actin and filamentous actin, while immunofluorescent staining and scratch assays were utilized to assess cell proliferation and migration. RESULTS: Compared to the shNC + AA group, the shROCK1 + AA group exhibited decreased levels of ROCK1 and MYOCD mRNA and protein expression, reduced expression levels of globular actin and filamentous actin, and diminished cell proliferation and migration capabilities (P<0.05). CONCLUSIONS: Inhibition of the Rho/ROCK pathway suppresses the proliferation and migration of airway smooth muscle cells, which may be associated with the downregulation of MYOCD.


Asunto(s)
Movimiento Celular , Proliferación Celular , Miocitos del Músculo Liso , Transducción de Señal , Transactivadores , Quinasas Asociadas a rho , Quinasas Asociadas a rho/metabolismo , Quinasas Asociadas a rho/fisiología , Quinasas Asociadas a rho/genética , Humanos , Miocitos del Músculo Liso/fisiología , Miocitos del Músculo Liso/metabolismo , Células Cultivadas , Transactivadores/genética , Transactivadores/fisiología , Transactivadores/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , Proteínas Nucleares/metabolismo , Proteínas de Unión al GTP rho/fisiología , Proteínas de Unión al GTP rho/genética , Proteínas de Unión al GTP rho/metabolismo
3.
Mol Genet Genomic Med ; 12(9): e70006, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39235128

RESUMEN

BACKGROUND: Paired box gene 2 (PAX2) heterozygous mutations can cause renal coloboma syndrome, but its role in patients with focal segmental glomerular sclerosis (FSGS) has been rarely reported. METHODS: Based on the clinical manifestations and renal pathological characteristics of the patient, as well as familial whole exome sequencing, the diagnosis of FSGS related to PAX2 mutation was confirmed. Treatment such as lowering urinary protein and blood pressure was given, and the patient was followed up and observed. RESULTS: There is a familial heterozygous case presented with chronic kidney disease secondary to FSGS, which was related to PAX2 frameshift mutation due to the deletion of G at the position 76 (c.76delG). To our knowledge, this is the first report of PAX2 c.76delG variant related to adult-onset FSGS. CONCLUSION: Here, we further expand the phenotypic spectrum of FSGS. Genetic screening especially PAX2 mutation is recommended in patients with adult-onset FSGS of unknown etiology.


Asunto(s)
Mutación del Sistema de Lectura , Glomeruloesclerosis Focal y Segmentaria , Factor de Transcripción PAX2 , Humanos , Factor de Transcripción PAX2/genética , Glomeruloesclerosis Focal y Segmentaria/genética , Glomeruloesclerosis Focal y Segmentaria/patología , Adulto , Masculino , Femenino , Linaje , Heterocigoto
4.
J Prosthodont ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39267252

RESUMEN

PURPOSE: To investigate the effect of different post-curing light intensities on the trueness, compressive strength, and resin polymerization of 3D-printed 3-unit fixed dental prostheses (FPD). MATERIALS AND METHODS: A total of 60 specimens were prepared to support a 3-unit FDP with a deep chamfer marginal design, utilizing computer-aided design and computer-aided manufacturing (CAD-CAM) technology. Light-polymerizing FDP resin with varying light intensities (105, 210, 420, and 840 mW/cm2) was employed for 10 min. Subsequently, trueness assessment, fracture load testing, scanning electron microscopy (SEM) surface examination, and Fourier-Transform Infrared (FTIR) analysis were conducted. A one-way analysis of variance (ANOVA) was performed to ascertain the differences between the experimental groups (p < 0.05). RESULTS: The group exposed to 210 mW/cm2 showed the highest trueness (57.6 ± 2.1 µm), while the 840 mW/cm2 group had the highest deviation (79.3 ± 2.7 µm) (p < 0.001). Significant differences in fracture resistance were found between groups (p < 0.001), with mean fracture strengths of 1149.77 ± 67.81 N, 1264.92 ± 39.06 N, 1331.34 ± 53.62 N, and 1439.93 ± 34.58 N for light intensities of 105, 210, 420, and 840 mW/cm2, respectively (p < 0.001). The resin polymerization analysis shows a peak intensity surge at 3579 cm-1 for O-H and C-H stretching vibrations, except in samples exposed to 105 mw/cm2 light, with the lowest peak at 2890 cm-1. The performance of resin polymerization is most significant under the condition of 840 mW/cm2. CONCLUSION: The light intensity of 210 mW/cm2 exhibited the highest trueness, while the 840 mW/cm2 group showed the highest deviation. However, the light intensity of 840 mW/cm2 demonstrated the highest compressive strength. Furthermore, polymerization occurred at all post-treatment light intensities except 105 mW/cm2. These findings indicate that while low-intensity usage offers greater trueness, high-intensity usage provides better compressive strength and polymerization. Therefore, 210 mW/cm2 could be the recommended solution for post-curing.

5.
EClinicalMedicine ; 75: 102794, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39281098

RESUMEN

Background: Autoimmune diseases are known to be associated with an increased risk of cancer. Whether maternal immune dysregulation can have an impact on the development of haematological malignancies in offspring remains uncertain. Therefore, we explored the association between offspring risk of haematological malignancies and maternal autoimmune disease using a real-world nationwide population-based study. Methods: In this case-control study, we identified 2172 children with haematological malignancies between 2004 and 2019 from Taiwan's National Health Insurance program and compared them with population-based controls without haematologic malignancies, who were matched with each individual at a ratio of 1:4. The medical information of the autoimmune mothers were obtained from the Taiwan Maternal and Child Health Database. Conditional logistic regression was used to estimate the odds ratio for haematologic malignancy in offspring. Furthermore, subgroup and stratified analyses were conducted. Findings: Among the rheumatologic diseases in our study, Crohn's disease was the most common disease both in the haematological malignancy group (1.1%) and the control group (0.9%). In multivariable analysis, the odds ratio for haematological malignancy in offspring with maternal autoimmune diseases was 1.2 (95% confidence interval [CI] 0.91-1.58). The overall risk of haematologic malignancy was not significantly higher when adjusted for specific risk factors, including neonatal age, maternal age, family income, urbanization, maternal occupation, birth weight, or maternal comorbidity, except for prematurity. When comparing different autoimmune diseases among haematological malignancies and the control group, maternal psoriatic arthritis/psoriasis had the highest adjusted overall risk for haematological malignancies (adjusted OR 2.11, CI 0.89-5), followed by ankylosing spondylitis (adjusted OR 1.45, CI 0.7-3), autoimmune thyroiditis (OR 1.26, CI 0.57-2.81), systemic lupus erythematosus (OR 1.21, CI 0.48-3.02), Crohn's disease (OR 1.19, CI 0.75-1.9), and Sjogren's syndrome (OR 1.18, CI 0.65-2.15), but no significance was reached in these analyses. Multivariable analysis of risk factors associated with haematological malignancy subtypes was done. It showed no associations between maternal autoimmune disease and childhood haematological malignancies. Interpretation: We found no significant relationship between maternal autoimmune disease and childhood haematological malignancies. The influence of maternal immune dysregulation on the next generation with respect to haematological malignancies development may be limited. Funding: There was no funding source for this study.

6.
Redox Rep ; 29(1): 2394714, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39284589

RESUMEN

Neonatal hypoxic-ischemic encephalopathy (HIE) is a severe disease with a poor prognosis, whose clinical treatment is still limited to therapeutic hypothermia with limited efficacy. Perillyl alcohol (POH), a natural monoterpene found in various plant essential oils, has shown neuroprotective properties, though its effects on HIE are not well understood. This study investigates the neuroprotective effects of POH on HIE both in vitro and in vivo. We established an in vitro model using glucose deprivation and hypoxia/reperfusion (OGD/R) in PC12 cells, alongside an in vivo model via the modified Rice-Vannucci method. Results indicated that POH acted as an indirect antioxidant, reducing inducible nitric oxide synthase and malondialdehyde production, maintaining content of antioxidant molecules and enzymes in OGD/R-induced PC12 cells. In vivo, POH remarkably lessened infarct volume, reduced cerebral edema, accelerated tissue regeneration, and blocked reactive astrogliosis after hypoxic-ischemic brain injury. POH exerted antiapoptotic activities through both the intrinsic and extrinsic apoptotic pathways. Mechanistically, POH activated Nrf2 and inactivated its negative regulator Keap1. The use of ML385, a Nrf2 inhibitor, reversed these effects. Overall, POH mitigates neuronal damage in HIE by combating oxidative stress, reducing inflammation, and inhibiting apoptosis via the Nrf2/Keap1 pathway, suggesting its potential for HIE treatment.


Asunto(s)
Animales Recién Nacidos , Hipoxia-Isquemia Encefálica , Proteína 1 Asociada A ECH Tipo Kelch , Monoterpenos , Factor 2 Relacionado con NF-E2 , Fármacos Neuroprotectores , Transducción de Señal , Animales , Factor 2 Relacionado con NF-E2/metabolismo , Ratas , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/metabolismo , Transducción de Señal/efectos de los fármacos , Monoterpenos/farmacología , Monoterpenos/uso terapéutico , Células PC12 , Estrés Oxidativo/efectos de los fármacos , Ratas Sprague-Dawley , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos
7.
Innovation (Camb) ; 5(5): 100689, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39285907
8.
Clin Kidney J ; 17(9): sfae264, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39286239

RESUMEN

Background: The remission rate of myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) patients who received standard induction therapy is far from satisfactory. Improving the remission rate of MPO-AAV patients is essential. Hydroxychloroquine (HCQ), one of the classic antimalarial drugs, has been widely used in various autoimmune rheumatic diseases. This retrospective observational cohort study is aimed to evaluate the efficacy and safety of HCQ during induction treatment for MPO-AAV. Methods: The medical records of patients diagnosed with MPO-AAV at Xiangya Hospital, Central South University from January 2021 to September 2023 were collected. They were assigned to the HCQ group or control group according to whether they used HCQ. The patients included were screened by propensity score matching. To evaluate whether MPO-AAV patients benefited from HCQ, we compared the prognosis of the two groups. The adverse effects of HCQ during follow-up were recorded. Results: The composition ratio of complete remission, response and treatment resistance between HCQ group and control group were different statistically (P = .021). There was no significant difference between the two groups in 1-year renal survival (P = .789). The HCQ group had better 1-year patient survival than the control group (P = .049). No serious adverse effects were documented in the HCQ group. Conclusions: HCQ together with standard induction treatment may improve the remission rate of MPO-AAV patients, and HCQ had good safety in our study.

9.
J Am Heart Assoc ; : e036663, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291501

RESUMEN

BACKGROUND: Apical hypertrophic cardiomyopathy (ApHCM) is a variant of hypertrophic cardiomyopathy, with distinct clinical characteristics and outcomes. We aimed to clarify the natural history of patients with ApHCM and identify the risk of end-stage heart failure incidence. METHODS AND RESULTS: This retrospective study was conducted on patients with hypertrophic cardiomyopathy in China between January 2009 and February 2024. Patients were stratified into ApHCM and non-ApHCM groups. The primary outcome was a composite of major adverse cardiovascular events, including all-cause deaths, heart failure hospitalization, sudden cardiac death, and ventricular tachycardia. The secondary outcome was the incidence of end-stage heart failure, defined as left ventricular ejection fraction <50%. Kaplan-Meier and univariable and multivariable Cox proportional analyses were applied. Adjustment variables were included for important baseline characteristics, comorbidities, and medication use. Of 5653 patients enrolled with hypertrophic cardiomyopathy, 584 (10.3%) had ApHCM and 5069 (89.7%) had non-ApHCM. During the median follow-up period of 4.6 years (1.6-8.0 years), major adverse cardiovascular events occurred in 32.2% (n=1808), with a lower incidence in patients with ApHCM than non-ApHCM (20.4% versus 33.3%, P<0.001). Non-ApHCM was an independent predictor of major adverse cardiovascular events (hazard ratio [HR], 1.65 [95% CI, 1.36-1.99]; P<0.001). In the serial cohort, patients with ApHCM exhibited a lower incidence of end-stage heart failure than those with non-ApHCM (12.4% versus 2.7%, P<0.001). Non-ApHCM was associated with a higher risk of end-stage heart failure development (HR, 2.31 [95% CI, 1.28-4.15]; P<0.001). In subgroup and sensitivity analysis, the results were consistent for our main and secondary outcomes. CONCLUSIONS: ApHCM is relatively common in hypertrophic cardiomyopathy and shows lower rates of all-cause mortality and heart failure hospitalizations than non-ApHCM.

10.
Molecules ; 29(17)2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39275065

RESUMEN

This study presents the synthesis, structural characterization, and evaluation of the photocatalytic performance of two novel one-dimensional (1D) lead(II) bromide hybrids, [Co(2,2'-bpy)3][Pb2Br6CH3OH] (1) and [Fe(2,2'-bpy)3][Pb2Br6] (2), synthesized via solvothermal reactions. These compounds incorporate transition metal complex cations as structural directors, contributing to the unique photophysical and photocatalytic properties of the resulting materials. Single-crystal X-ray diffraction analysis reveals that both compounds crystallize in monoclinic space groups with distinct 1D lead bromide chain configurations influenced by the nature of the complex cations. Optical property assessments show band gaps of 3.04 eV and 2.02 eV for compounds 1 and 2, respectively, indicating their potential for visible light absorption. Photocurrent measurements indicate a significantly higher electron-hole separation efficiency in compound 2, correlated with its narrower band gap. Additionally, photocatalytic evaluations demonstrate that while both compounds degrade organic dyes effectively, compound 2 also exhibits notable hydrogen evolution activity under visible light, a property not observed in 1. These findings highlight the role of metal complex cations in tuning the electronic and structural properties of lead(II) bromide hybrids, enhancing their applicability in photocatalytic and optoelectronic devices.

11.
Bone Joint Res ; 13(9): 497-506, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39278635

RESUMEN

Aims: Advances in treatment have extended the life expectancy of patients with metastatic bone disease (MBD). Patients could experience more skeletal-related events (SREs) as a result of this progress. Those who have already experienced a SRE could encounter another local management for a subsequent SRE, which is not part of the treatment for the initial SRE. However, there is a noted gap in research on the rate and characteristics of subsequent SREs requiring further localized treatment, obligating clinicians to extrapolate from experiences with initial SREs when confronting subsequent ones. This study aimed to investigate the proportion of MBD patients developing subsequent SREs requiring local treatment, examine if there are prognostic differences at the initial treatment between those with single versus subsequent SREs, and determine if clinical, oncological, and prognostic features differ between initial and subsequent SRE treatments. Methods: This retrospective study included 3,814 adult patients who received local treatment - surgery and/or radiotherapy - for bone metastasis between 1 January 2010 and 31 December 2019. All included patients had at least one SRE requiring local treatment. A subsequent SRE was defined as a second SRE requiring local treatment. Clinical, oncological, and prognostic features were compared between single SREs and subsequent SREs using Mann-Whitney U test, Fisher's exact test, and Kaplan-Meier curve. Results: Of the 3,814 patients with SREs, 3,159 (83%) patients had a single SRE and 655 (17%) patients developed a subsequent SRE. Patients who developed subsequent SREs generally had characteristics that favoured longer survival, such as higher BMI, higher albumin levels, fewer comorbidities, or lower neutrophil count. Once the patient got to the point of subsequent SRE, their clinical and oncological characteristics and one-year survival (28%) were not as good as those with only a single SRE (35%; p < 0.001), indicating that clinicians' experiences when treating the initial SRE are not similar when treating a subsequent SRE. Conclusion: This study found that 17% of patients required treatments for a second, subsequent SRE, and the current clinical guideline did not provide a specific approach to this clinical condition. We observed that referencing the initial treatment, patients in the subsequent SRE group had longer six-week, 90-day, and one-year median survival than patients in the single SRE group. Once patients develop a subsequent SRE, they have a worse one-year survival rate than those who receive treatment for a single SRE. Future research should identify prognostic factors and assess the applicability of existing survival prediction models for better management of subsequent SREs.

12.
Ecology ; : e4415, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39267580

RESUMEN

Soil microbes have long been recognized to substantially affect the coexistence of pairwise plant species across terrestrial ecosystems. However, projecting their impacts on the coexistence of multispecies plant systems remains a pressing challenge. To address this challenge, we conducted a greenhouse experiment with 540 seedlings of five tree species in a subtropical forest in China and evaluated microbial effects on multispecies coexistence using the structural method, which quantifies how the structure of species interactions influences the likelihood for multiple species to persist. Specifically, we grew seedlings alone or with competitors in different microbial contexts and fitted individual biomass to a population dynamic model to calculate intra- and interspecific interaction strength with and without soil microbes. We then used these interaction structures to calculate two metrics of multispecies coexistence, structural niche differences (which promote coexistence) and structural fitness differences (which drive exclusion), for all possible communities comprising two to five plant species. We found that soil microbes generally increased both the structural niche and fitness differences across all communities, with a much stronger effect on structural fitness differences. A further examination of functional traits between plant species pairs found that trait differences are stronger predictors of structural niche differences than of structural fitness differences, and that soil microbes have the potential to change trait-mediated plant interactions. Our findings underscore that soil microbes strongly influence the coexistence of multispecies plant systems, and also add to the experimental evidence that the influence is more on fitness differences rather than on niche differences.

13.
Diagnostics (Basel) ; 14(17)2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39272637

RESUMEN

Proteinuria is a common adverse event arising from treatment with bevacizumab, requiring diagnostic testing via 24-h urine collection. However, this method is cumbersome. We assessed urine screenings in gynecologic cancer patients from February 2021 to May 2022. Along with a simple urine dipstick (UD), the urine microalbumin, total protein, and creatinine were measured and calculated as the urine albumin to creatinine ratio (UACR) and the urine protein to creatinine ratio (UPCR), which were further adjusted through the Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration equations to be estimated and correlated with 24-h urine total protein content. The incremental cost-effectiveness ratio was used for cost analysis. There were 129 urine samples from 36 patients. The sensitivity and specificity for the UACR were 0.56 and 0.97, and for the UPCR, 0.71 and 0.88, respectively. The 24-h TP correlated strongly with the UACR (r = 0.75; p < 0.001) and UPCR (r = 0.79; p < 0.001) and fair for the simple UD (r = 0.35; p < 0.001). The UPCR saves one unnecessary 24-h urine test for less than a dollar compared to a simple UD. The results indicate that using the UPCR could enhance diagnostic accuracy, lower costs, and reduce unnecessary 24-h urine sampling.

14.
J Asthma ; : 1-10, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269783

RESUMEN

OBJECTIVE: This study aimed to explore the effects of Parkin (Prkn) knockout in a juvenile mouse model of asthma. METHODS: Prkn knockout (KO) and wild type (WT) mice were utilized to establish a juvenile mouse asthma model. The asthma model involved exposure to hyperoxia/ovalbumin (OVA), encompassing hyperoxia from postnatal day 1 (P1) to P7, sensitization on P21 and P28, and challenge from P36 to P42. Room air/phosphate-buffered saline (PBS) served as the control condition. Following airway resistance measurement, bronchoalveolar lavage fluid (BALF) was collected for cellular analysis, and lung tissues were subjected to histological examination and oxidative stress assessment. Serum levels of ovalbumin-specific immunoglobulin E (IgE), total IgE, interleukin-4 (IL-4), IL-5, and IL-13 were quantified using enzyme-linked immunosorbent assay (ELISA). RESULTS: WT mice exposed to hyperoxia/OVA showed decreased body weight and increased airway resistance compared to those exposed to control condition. Conversely, KO mice exhibited increased body weight under asthma conditions. KO mice with asthma had reduced total cell counts, along with lower levels of lymphocytes, eosinophils, and neutrophils, compared to WT asthma mice. Histological assessment showed attenuated inflammation and reduced collagen deposition in KO mice relative to WT mice, with lower serum levels of inflammatory markers and improved lung oxidative stress profiles. No significant differences were observed between KO and WT mice under room air/PBS conditions. CONCLUSIONS: Parkin knockout in juvenile mice mitigates asthma-related alterations in airway resistance, histopathological changes, inflammation status, and oxidative stress. These findings highlight a protective role of Parkin deficiency against asthma-associated pathologies.

15.
Phys Rev Lett ; 133(9): 096302, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39270171

RESUMEN

The quantum Hall (QH) effect is one of the most widely studied physical phenomenon in two dimensions. The plateau-plateau transition within this effect can be comprehensively described by the scaling theory, which encompasses three pivotal exponents: the critical exponent κ, the inelastic scattering exponent p, and the universal exponent γ. Prior studies have focused on measuring κ and estimating γ, assuming a constant p value of 2 across magnetic fields. Here, our work marks a significant advancement by measuring all three exponents within a single graphene device and a conventional two-dimensional electron system. This study uniquely determines p at low magnetic fields (weak localization region and well outside the QH regime) and high magnetic fields (in the vicinity of the QH regime). Employing a comprehensive analytical approach that includes weak localization, plateau-plateau transitions, and variable range hopping, we have directly determined κ, p, and γ. Our findings reveal a distinct variation in p, shifting from 1 in the low magnetic field regime to 2 in the QH regime in graphene.

16.
Biosystems ; 246: 105334, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39265923

RESUMEN

Enzymatic reactions are essential for most cellular reactions and ubiquitous in living organisms. In the present study, we explore the pivotal role of the reverse reaction in enzymatic reactions. It is a powerful noise-buffering motif. By SSA (stochastic simulation algorithm), a remarkable 32% reduction of product CV (coefficient of variation) was observed. To better understand the causes, we split the upstream noise. The product CV reduction is more than 35% for the noise inherited from the enzyme but merely 6%-21% for that from the substrate. It implies that the system applies different strategies to different upstream noises. We identified two leading causes responsible for noise attenuation. A cell is well designed to control its intracellular noise, and to acquire wisdom from nature is always enjoyable.

17.
Bioresour Technol ; 413: 131461, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39255945

RESUMEN

Eco-friendly enzymatic-recycling has been widely utilized in tackling plastic pollution. However, the limited activity on the polyethylene terephthalate (PET) degradation product mono-hydroxyethyl terephthalate (MHET) leads to the formation of heterogeneous hydrolysis products, resulting in PET downcycling. Herein, by applying a dual-function PET hydrolase IsPETasePA with balanced PET and MHET degradation efficiency, an effective PET hydrolysis process was developed to enhance the terephthalic acid (TPA) product purity. Firstly, the impact of pH on the catalytic activity of IsPETasePA revealed that the pH reduction caused by TPA generation hindered the complete conversion of MHET to TPA. Further investigation of the catalytic mechanism showed that the pH-induced protonation of His208 in the catalytic triad destabilized the interaction between IsPETasePA and MHET. Thus, by introducing pH regulation strategy on the bifunctional IsPETasePA, the single-enzyme process could achieve high-purity TPA recovery (>99 %). Overall, this work ensured the high-quality PET enzymatic-recycling for effectively addressing plastic pollution.

18.
BMC Geriatr ; 24(1): 732, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39232713

RESUMEN

BACKGROUND: Central obesity was considered as a risk factor for falls among the older population. Waist circumference (WC), lipid accumulation product (LAP), visceral adiposity index (VAI), and the Chinese visceral adiposity index (CVAI) are considered as surrogate markers for abdominal fat deposition in increasing studies. Nevertheless, the longitudinal relationship between these indices and falls among the older population remains indistinct. This study aimed to explore the association between abdominal obesity indices and falls among older community-dwellers. METHODS: Our study included 3501 individuals aged ≥ 65 years from the Guangzhou Falls and Health Status Tracking Cohort at baseline in 2021 and then prospectively followed up in 2022. The outcome of interest was the occurrence of falls. The Kaplan-Meier curves and multivariable Cox regression analysis were used to explore the associations between abdominal obesity indices and falls. Moreover, the restricted cubic spline analysis (RCS) was conducted to test the non-linear relationships between abdominal obesity indices and hazards of falls incident. RESULTS: After a median follow-up period of 551 days, a total of 1022 participants experienced falls. The cumulative incidence rate of falls was observed to be higher among individuals with central obesity and those falling within the fourth quartile (Q4) of LAP, VAI, and CVAI. Participants with central obesity and those in Q4 of LAP, VAI, and CVAI were associated with higher risk of falls, with hazard ratios (HRs) of 1.422 (HR 95%CI: 1.255-1.611), 1.346 (1.176-1.541), 1.270 (1.108-1.457), 1.322 (1.154-1.514), respectively. Each 1-SD increment in WC, LAP, VAI, and CVAI was a significant increased risk of falls among participants. Subgroup analysis further revealed these results were basically stable and appeared to be significantly stronger among those females, aged 65-69 years, and with body mass index (BMI) ≥ 28 kg/m2. Additionally, RCS curves showed an overall upward trend in the risk of falls as the abdominal indices increased. CONCLUSIONS: Abdominal obesity indices, as WC, LAP, VAI, and CVAI were significantly associated with falls among older community-dwellers. Reduction of abdominal obesity indices might be suggested as the strategy of falls prevention.


Asunto(s)
Accidentes por Caídas , Vida Independiente , Obesidad Abdominal , Humanos , Obesidad Abdominal/epidemiología , Obesidad Abdominal/diagnóstico , Femenino , Masculino , Anciano , China/epidemiología , Estudios Prospectivos , Vida Independiente/tendencias , Factores de Riesgo , Circunferencia de la Cintura/fisiología , Anciano de 80 o más Años , Incidencia , Estudios de Cohortes
19.
Front Plant Sci ; 15: 1437769, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39220005

RESUMEN

Introduction: Negative oxygen ions are produced by plants through photosynthesis, utilizing "tip discharge" or the photoelectric effect, which has various functions such as sterilization, dust removal, and delaying aging. With global warming, high temperatures may affect the ability of Phalaenopsis aphrodite Rchb. f. to produce negative oxygen ions. P. aphrodite is commonly used in modern landscape planning and forest greening. Methods: In this study, P. aphrodite was selected as the research object. By artificially simulating the climate, the control group (CK) and the high temperature stress group (HS) were set up in the experiment. Results: The study found that compared with the control group, the ability of P. aphrodite to produce negative oxygen ions significantly decreased when exposed to high temperature stress. Meanwhile, under high temperature stress treatment, peroxidase content increased by 102%, and proline content significantly increased by 35%. Discussion: Redundancy analysis results indicated a significant correlation between the root endophytic microbial community of P. aphrodite and negative oxygen ions, as well as physiological indicators. Under high temperature stress, P. aphrodite may affect the regulation of physiological indicators by modifying the composition of root endophytic microbial communities, thereby influencing the ability to release negative oxygen ions.

20.
Angew Chem Int Ed Engl ; : e202409515, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39228207

RESUMEN

Gallium (Ga) with a low melting point can serve as a unique metallic solvent in the synthesis of intermetallic compounds (IMCs). The negative formation enthalpy of transition metal-Ga IMCs endows them with high catalytic stability. Meanwhile, their tunable crystal structures offer the possibility to tailor the configurations of active sites to meet the requirements for specific catalytic applications. Herein, we present a general method for preparing a range of transition metal-Ga IMCs, including Co-Ga, Ni-Ga, Pt-Ga, Pd-Ga, and Rh-Ga IMCs. The structurally ordered CoGa IMCs with body-centered cubic (bcc) structure are uniformly dispersed on the nitrogen-doped reduced graphene oxide substrate (O-CoGa/NG) and deliver outstanding nitrate reduction reaction (NO3RR) performance, making them excellent catalysts to construct highly efficient rechargeable Zn-NO3- battery. Operando studies and theoretical simulations demonstrate that the electron-rich environments around the Co atoms enhance the adsorption strength of *NO3 intermediate and simultaneously suppress the formation of hydrogen, thus improving the NO3RR activity and selectivity.

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