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1.
Nature ; 633(8030): 548-553, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39232172

RESUMO

Exploring new strategies to manipulate the order parameter of magnetic materials by electrical means is of great importance not only for advancing our understanding of fundamental magnetism but also for unlocking potential applications. A well-established concept uses gate voltages to control magnetic properties by modulating the carrier population in a capacitor structure1-5. Here we show that, in Pt/Al/Fe/GaAs(001) multilayers, the application of an in-plane charge current in Pt leads to a shift in the ferromagnetic resonance field depending on the microwave frequency when the Fe film is sufficiently thin. The experimental observation is interpreted as a current-induced modification of the magnetocrystalline anisotropy ΔHA of Fe. We show that (1) ΔHA decreases with increasing Fe film thickness and is connected to the damping-like torque; and (2) ΔHA depends not only on the polarity of charge current but also on the magnetization direction, that is, ΔHA has an opposite sign when the magnetization direction is reversed. The symmetry of the modification is consistent with a current-induced spin6-8 and/or orbit9-13 accumulation, which, respectively, act on the spin and/or orbit component of the magnetization. In this study, as Pt is regarded as a typical spin current source6,14, the spin current can play a dominant part. The control of magnetism by a spin current results from the modified exchange splitting of the majority and minority spin bands, providing functionality that was previously unknown and could be useful in advanced spintronic devices.

2.
Nature ; 604(7907): 732-739, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418674

RESUMO

The gut microbiome is associated with diverse diseases1-3, but a universal signature of a healthy or unhealthy microbiome has not been identified, and there is a need to understand how genetics, exposome, lifestyle and diet shape the microbiome in health and disease. Here we profiled bacterial composition, function, antibiotic resistance and virulence factors in the gut microbiomes of 8,208 Dutch individuals from a three-generational cohort comprising 2,756 families. We correlated these to 241 host and environmental factors, including physical and mental health, use of medication, diet, socioeconomic factors and childhood and current exposome. We identify that the microbiome is shaped primarily by the environment and cohabitation. Only around 6.6% of taxa are heritable, whereas the variance of around 48.6% of taxa is significantly explained by cohabitation. By identifying 2,856 associations between the microbiome and health, we find that seemingly unrelated diseases share a common microbiome signature that is independent of comorbidities. Furthermore, we identify 7,519 associations between microbiome features and diet, socioeconomics and early life and current exposome, with numerous early-life and current factors being significantly associated with microbiome function and composition. Overall, this study provides a comprehensive overview of gut microbiome and the underlying impact of heritability and exposures that will facilitate future development of microbiome-targeted therapies.


Assuntos
Microbioma Gastrointestinal , Bactérias/genética , Dieta , Meio Ambiente , Humanos , Estilo de Vida , Países Baixos , Fatores Socioeconômicos
3.
Nature ; 594(7861): 33-36, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34002091

RESUMO

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

4.
Nature ; 568(7752): 368-372, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30996320

RESUMO

Complex topological configurations are fertile ground for exploring emergent phenomena and exotic phases in condensed-matter physics. For example, the recent discovery of polarization vortices and their associated complex-phase coexistence and response under applied electric fields in superlattices of (PbTiO3)n/(SrTiO3)n suggests the presence of a complex, multi-dimensional system capable of interesting physical responses, such as chirality, negative capacitance and large piezo-electric responses1-3. Here, by varying epitaxial constraints, we discover room-temperature polar-skyrmion bubbles in a lead titanate layer confined by strontium titanate layers, which are imaged by atomic-resolution scanning transmission electron microscopy. Phase-field modelling and second-principles calculations reveal that the polar-skyrmion bubbles have a skyrmion number of +1, and resonant soft-X-ray diffraction experiments show circular dichroism, confirming chirality. Such nanometre-scale polar-skyrmion bubbles are the electric analogues of magnetic skyrmions, and could contribute to the advancement of ferroelectrics towards functionalities incorporating emergent chirality and electrically controllable negative capacitance.

5.
Small ; 20(11): e2309454, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38098368

RESUMO

The optimal treatment for tracheal tumors necessitates sequential tumor elimination and tracheal cartilage reconstruction. This study introduces an innovative inorganic nanosheet, MnO2 /PDA@Cu, comprising manganese dioxide (MnO2 ) loaded with copper ions (Cu) through in situ polymerization using polydopamine (PDA) as an intermediary. Additionally, a specialized methacrylic anhydride modified decellularized cartilage matrix (MDC) hydrogel with chondrogenic effects is developed by modifying a decellularized cartilage matrix with methacrylic anhydride. The MnO2 /PDA@Cu nanosheet is encapsulated within MDC-derived microneedles, creating a photothermal-controllable MnO2 /PDA@Cu-MDC microneedle. Effectiveness evaluation involved deep insertion of the MnO2 /PDA@Cu-MDC microneedle into tracheal orthotopic tumor in a murine model. Under 808 nm near-infrared irradiation, facilitated by PDA, the microneedle exhibited rapid overheating, efficiently eliminating tumors. PDA's photothermal effects triggered controlled MnO2 and Cu release. The MnO2 nanosheet acted as a potent inorganic nanoenzyme, scavenging reactive oxygen species for an antioxidant effect, while Cu facilitated angiogenesis. This intervention enhanced blood supply at the tumor excision site, promoting stem cell enrichment and nutrient provision. The MDC hydrogel played a pivotal role in creating a chondrogenic niche, fostering stem cells to secrete cartilaginous matrix. In conclusion, the MnO2 /PDA@Cu-MDC microneedle is a versatile platform with photothermal control, sequentially combining antitumor, antioxidant, pro-angiogenic, and chondrogenic activities to orchestrate precise tracheal tumor eradication and cartilage regeneration.


Assuntos
Nanopartículas , Neoplasias , Neoplasias da Traqueia , Humanos , Camundongos , Animais , Antioxidantes , Compostos de Manganês , Óxidos , Neoplasias/patologia , Cartilagem , Hidrogéis , Anidridos
6.
Opt Express ; 32(8): 14054-14066, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859361

RESUMO

We present a laser-driven interferometric fiber optic gyroscope (IFOG) with polarization self-compensation to achieve high scale-factor stability, sensitivity, and long-term stability. Coherent light with 200kHz linewidth is employed to keep the scale factor stable. The optical scheme ensures polarization reciprocity as well as the optimal working point for good sensitivity. Furthermore, a hybrid machine learning loop (MLL) method, combining the advantages of PID fast response and artificial neural network (ANN) dynamic search, can control a liquid crystal rotator (LCR) to dynamically compensate for slow drift induced by polarization coupling. In open environment, when the sensitivity is 0.005 ∘/h, the bias instability (BI) is significantly optimized from 0.6723°/h at 60s (PID) to 0.3869°/h at 200s (MLL), which is close to the Sagnac interferometric limit (SIL). Such IFOG can meet the real-time and robust requirements for inertial navigation systems in long-term measurement.

7.
Opt Express ; 32(7): 12982-12991, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571104

RESUMO

Quantum dense metrology (QDM) performs high-precision measurements by a two-mode entangled state created by an optical parametric amplifier (PA), where one mode is a meter beam and the other is a reference beam. In practical applications, the photon losses of meter beam are unavoidable, resulting in a degradation of the sensitivity. Here, we employ coherent feedback that feeds the reference beam back into the PA by a beam splitter to enhance the sensitivity in a lossy environment. The results show that the sensitivity is enhanced significantly by adjusting the splitting ratio of the beam splitter. This method may find its potential applications in QDM. Furthermore, such a strategy that two non-commuting observables are simultaneous measurements could provide a new way to individually control the noise-induced random drift in phase or amplitude of the light field, which would be significant for stabilizing the system and long-term precision measurement.

8.
Phys Rev Lett ; 132(21): 213602, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38856267

RESUMO

The approach of shortcuts to adiabaticity enables the effective execution of adiabatic dynamics in quantum information processing with enhanced speed. Owing to the inherent trade-off between dynamical speed and the cost associated with the transitionless driving field, executing arbitrarily fast operations becomes impractical. To understand the accurate interplay between speed and energetic cost in this process, we propose theoretically and verify experimentally a new trade-off, which is characterized by a tightly optimized bound within s-parametrized phase spaces. Our experiment is carried out in a single ultracold ^{40}Ca^{+} ion trapped in a harmonic potential. By exactly operating the quantum states of the ion, we execute the Landau-Zener model as an example, where the quantum speed limit as well as the cost are governed by the spectral gap. We witness that our proposed trade-off is indeed tight in scenarios involving both initially eigenstates and initially thermal equilibrium states. Our work helps understanding the fundamental constraints in shortcuts to adiabaticity and illuminates the potential of underutilized phase spaces that have been traditionally overlooked.

9.
Phys Rev Lett ; 133(9): 090402, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39270181

RESUMO

The limit of energy saving in the control of small systems has recently attracted much interest due to the concept refinement of the Maxwell demon. Inspired by a newly proposed set of fluctuation theorems, we report the first experimental verification of these equalities and inequalities in an ultracold ^{40}Ca^{+} ion system, confirming the intrinsic nonequilibrium in the system due to involvement of the demon. Based on elaborately designed demon-involved control protocols, such as the Szilard engine protocol, we provide experimentally quantitative evidence of the dissipative information and observe tighter bounds of both the extracted work and the demon's efficacy than the limits predicted by the Sagawa-Ueda theorem. Our results substantiate a close connection between the physical nature of information and nonequilibrium processes at the microscale, which help to further understand the thermodynamic characteristics of information and the optimal design of nanoscale and smaller systems.

10.
Phys Rev Lett ; 132(18): 180401, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38759168

RESUMO

Although entanglement is considered as an essential resource for quantum information processing, whether entanglement helps for energy conversion or output in the quantum regime is still lack of experimental witness. Here, we report on an energy-conversion device operating as a quantum engine with the working medium acted by two entangled ions confined in a harmonic potential. The two ions are entangled by virtually coupling to one of the vibrational modes shared by the two ions, and the quantum engine couples to a quantum load, which is another shared vibrational mode. We explore the energy conversion efficiency of the quantum engine and investigate the useful energy (i.e., the maximum extractable work) stored in the quantum load by tuning the two ions in different degrees of entanglement as well as detecting the change of the phonons in the load. Our observation provides, for the first time, quantitative evidence that entanglement fuels the useful energy produced by the quantum engine, but not helpful for the energy conversion efficiency. We consider that our results may be useful to the study of quantum batteries for which one of the most indexes is the maximum extractable energy.

11.
Environ Sci Technol ; 58(39): 17386-17395, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39298651

RESUMO

Brown carbon (BrC) has a substantial direct radiative effect, but current estimates of its impact on radiative balance are highly uncertain due to a lack of measurements of its light-absorbing properties, such as mass absorption efficiency (MAE). Here, we present a new analytical paradigm based on a Bayesian inference (BI) model that takes multiwavelength aethalometer measurements and total carbon data to resolve the concentrations of black carbon and BrC, and MAEs of BrC on a sample-by-sample basis. Hourly MAEs, unattainable in previous studies, can now be calculated, enabling the first-time observation of the darkening-bleaching dynamics of BrC in response to photochemical transformation. We demonstrate the application of this BI model to analyze measurements collected over one year (2021-2022) in Hong Kong. Diel variations in MAE370 nm of BrC reveal a darkening-to-bleaching transition occurring between 8 and 10 O'clock when the solar irradiance ranges from 30 to 400 W m-2. Furthermore, we consistently observe an increase in MAE370 nm of BrC with nitrogen oxide concentrations, suggesting the enhanced formation of nitrogenous organics. This BI model-based data analysis would bring forth a breakthrough in amassing observation data of BrC and its MAEs in diverse ambient environments and with high time resolution.


Assuntos
Carbono , Teorema de Bayes , Monitoramento Ambiental/métodos
12.
Ultrasound Obstet Gynecol ; 63(4): 522-528, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-37767731

RESUMO

OBJECTIVE: Radiofrequency ablation (RFA) is the preferred approach for selective reduction in complex monochorionic (MC) multiple pregnancies owing to the ease of operation and minimal invasiveness. To optimize the RFA technique and reduce the risk of adverse pregnancy outcome resulting from the heat-sink effect of RFA therapy, we used an innovative RFA method, in which an electrode needle was expanded incrementally and stepwise. This study aimed to assess the efficacy and safety profile of this novel multistep incremental expansion RFA method for selective fetal reduction in MC twin and triplet pregnancies. METHODS: This was a single-center retrospective cohort study of all MC multiple pregnancies undergoing RFA between March 2016 and October 2022 at our center. The multistep RFA technique involved the use of an expandable needle, which was gradually expanded during the RFA procedure until cessation of umbilical cord blood flow was achieved. The needle used for the single-step RFA method was fully extended from the start of treatment. RESULTS: In total, 132 MC multiple pregnancies underwent selective reduction using RFA, including 50 cases undergoing multistep RFA and 82 cases undergoing single-step RFA. The overall survival rates were not significantly different between the multistep and single-step RFA groups (81.1% vs 72.3%; P = 0.234). Similarly, the rates of preterm prelabor rupture of the membranes within 2 weeks after RFA, procedure-related complications, spontaneous preterm delivery and pathological findings on cranial ultrasound, as well as gestational age at delivery and birth weight, did not differ between the two groups. However, there was a trend towards a prolonged procedure-to-delivery interval following multistep RFA compared with single-step RFA (median, 109 vs 99 days; P = 0.377). Moreover, the fetal loss rate within 2 weeks after RFA in the multistep RFA group was significantly lower than that in the single-step RFA group (10.0% vs 24.4%; P = 0.041). The median ablation time was shorter (5.3 vs 7.8 min; P < 0.001) and the median ablation energy was lower (10.2 vs 18.0 kJ; P < 0.001) in multistep compared with single-step RFA. There were no significant differences in neonatal outcomes following multistep vs single-step RFA. CONCLUSIONS: Overall survival rates were similar between the two RFA methods. However, the multistep RFA technique was associated with a lower risk of fetal loss within 2 weeks after RFA. The multistep RFA technique required significantly less ablation energy and a shorter ablation time compared with single-step RFA in selective fetal reduction of MC twin and triplet pregnancies. Additionally, there was a trend towards a prolonged procedure-to-delivery interval with the multistep RFA technique. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Ablação por Cateter , Gravidez de Trigêmeos , Ablação por Radiofrequência , Recém-Nascido , Feminino , Gravidez , Humanos , Gravidez de Gêmeos , Estudos Retrospectivos , Redução de Gravidez Multifetal/métodos , Ablação por Cateter/métodos , Resultado da Gravidez , Ablação por Radiofrequência/métodos , Idade Gestacional
13.
Clin Radiol ; 79(3): e462-e467, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38135576

RESUMO

AIM: To determine the effect of second-generation motion correction (MC2) on image quality and measurement reproducibility of cardiac CT images in patients with a myocardial bridge and mural coronary artery (MB-MCA) compared to standard (STD) images without motion correction and with first-generation motion correction (MC1). MATERIALS AND METHODS: A total of 66 patients with MB-MCA in the left anterior descending branch who underwent 256-detector CT with single-heartbeat acquisition were included. Images were reconstructed at 45% and 75% R-R intervals using STD, MC1, and MC2 algorithms. Image quality for MB-MCA was assessed by two observers on a four-point scale (1 = poor and 4 = excellent) and compared among STD, MC1, and MC2. Depth and length of MB, lumen area, and minimal diameter of MCA were measured and compared. RESULTS: At 45% R-R interval, image quality scores were 1.59 ± 0.78, 2.21 ± 0.97, and 3.21 ± 0.62 for MCA, and 2.48 ± 0.79, 2.76 ± 0.75, and 3.58 ± 0.58 for MB with STD, MC1 and MC2, respectively. At 75% R-R interval, these values were 2.26 ± 0.60, 3.03 ± 0.89, and 3.59 ± 0.55 for MCA and 3.00 ± 0.93, 3.17 ± 0.83, and 3.80 ± 0.44 for MB. Although MC1 was superior to STD in displaying MCA, there was no statistical difference between the two algorithms for MB (p>0.05). Compared with STD and MC1, MC2 statistically improved image quality and interpretability for both MCA and MB and had narrower limits in interobserver agreement for measurements at both 45% and 75% R-R intervals. CONCLUSION: MC2 improves CT image quality and measurement reproducibility in patients with MB-MCA compared to STD and MC1.


Assuntos
Angiografia por Tomografia Computadorizada , Vasos Coronários , Humanos , Vasos Coronários/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos , Angiografia Coronária/métodos , Movimento (Física) , Algoritmos
14.
Clin Radiol ; 79(7): e949-e956, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38641445

RESUMO

AIM: As a classic theranostic radiopharmaceutical, radioiodine (131I) has been utilized in the management of differentiated thyroid cancer (DTC) for more than 8 decades, and the refinement of its clinical practice has been raised recently. This study was conducted to evaluate the efficiency of a diagnostic (Dx) 131I scan in optimizing the indication of initial radioiodine oncolytic treatment (ROT) for metastatic DTC by predicting therapeutic outcomes. RESULTS: A total of 100 patients (Dx positive, n=29; Dx negative, n=71) were eligible for patient-based analysis. The matching rate was 83.0% between the Dx and the post-therapeutic scans (kappa = 0.648, P<0.001). The biochemical remission rate and structural shrinkage rate induced by the initial ROT in the Dx-positive group were, respectively, greater than those in the Dx-negative group (83.3% vs. 17.4%, P<0.001; 37.9% vs. 4.2%, P<0.001). Notably, the predictive values of positive Dx scans for ROT responsiveness and negative Dx scans for ROT nonresponsiveness reached up to 89.7% and 84.5%, respectively. CONCLUSION: This Dx scan approach seems viable in characterizing the 131I-avidity of metastatic DTC and plays a pivotal role in optimizing the indication of initial ROT for metastatic DTC.


Assuntos
Radioisótopos do Iodo , Neoplasias da Glândula Tireoide , Humanos , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Compostos Radiofarmacêuticos/uso terapêutico , Idoso , Resultado do Tratamento , Estudos Retrospectivos , Cintilografia , Adulto Jovem
15.
Antonie Van Leeuwenhoek ; 117(1): 16, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38189906

RESUMO

The unique eco-environment of the Qinghai-Tibet Plateau breeds abundant microbial resources. In this research, Bacillus amyloliquefaciens GL18, isolated from the rhizosphere of Kobresia myosuroides from an alpine meadow, and the antagonistic activity, bacteriostatic hydrolase activity, and low temperature, salt, and drought resistance of it were determined and analysed. The seedlings of Avena sativa were root-irrigated using bacteria suspensions (cell concentration 1 × 107 cfu/mL) of GL18, and the growth-promoting effect of GL18 on it was determined under cold, salt and drought stress, respectively. The whole genome of GL18 was sequenced, and its functional genes were analysed. GL18 presented significant antagonistic activity to Fusarium graminearum, Fusarium acuminatum, Fusarium oxysporum and Aspergillus niger (inhibition zone diameter > 17 mm). Transparent zones formed on four hydrolase detection media, indicating that GL18 secreted cellulase, protease, pectinase and ß-1,3-glucanase. GL18 tolerated conditions of 10 °C, 11% NaCl and 15% PEG-6000, presenting cold, salt and drought resistance. GL18 improved the cold, salt and drought tolerance of A. sativa and it showed significant growth effects under different stress. The total length of the GL18 genome was 3,915,550 bp, and the number of coding DNA sequence was 3726. Compared with the clusters of orthologous groups of proteins, gene ontology and kyoto encyclopedia of genes and genomes databases, 3088, 2869 and 2357 functional genes were annotated, respectively. GL18 contained gene clusters related to antibacterial substances, functional genes related to the synthesis of plant growth-promoting substances, and encoding genes related to stress resistance. This study identified an excellent Bacillus strain and provided a theoretical basis for improving stress resistance and promoting the growth of herbages under abiotic stress.


Assuntos
Bacillus amyloliquefaciens , Cyperaceae , Bacillus amyloliquefaciens/genética , Rizosfera , Pradaria , Cloreto de Sódio , Peptídeo Hidrolases
16.
J Endocrinol Invest ; 47(3): 619-631, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37725309

RESUMO

BACKGROUND: COVID-19 poses a significant threat to patients with comorbidities, such as diabetes and chronic kidney disease (CKD). China experienced a nationwide COVID-19 endemic from December 2022 to January 2023, which is the first occurrence of such an outbreak following China's widespread administration of COVID-19 vaccinations. METHODS: A total of 338 patients with diabetes and CKD combined with COVID-19 infection between December 7, 2022 and January 31, 2023 were included in this study. The end follow-up date was February 10, 2023. Univariate analysis and multivariate Cox analysis were used to analyze risk factors for death. RESULTS: During the 50-day median follow-up period, 90 patients in the study cohort died, for a mortality rate of 26.63%. The median age of the study cohort was 74 years, with a male predominance of 74%. During hospitalization, 21% of patients had incident AKI, 17% of patients experienced stroke, and 40% of patients experienced respiratory failure. Cox proportional hazard regression showed that older age, a diagnosis of severe or critically severe COVID-19 infection, incident AKI and respiratory failure, higher level of average values of fasting glucose during hospitalization, UA, and total bilirubin were independent risk factors for death in our multivariate model. CONCLUSIONS: These findings highlight the critical importance of identifying and managing comorbid risk factors for COVID-19, especially among the elderly, in order to optimize clinical outcomes, even after COVID-19 vaccination.


Assuntos
Injúria Renal Aguda , COVID-19 , Diabetes Mellitus , Insuficiência Renal Crônica , Insuficiência Respiratória , Idoso , Feminino , Humanos , Masculino , Injúria Renal Aguda/complicações , Injúria Renal Aguda/epidemiologia , COVID-19/complicações , COVID-19/epidemiologia , Vacinas contra COVID-19/administração & dosagem , Diabetes Mellitus/epidemiologia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco , Vacinação
17.
J Endocrinol Invest ; 47(6): 1559-1572, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38097848

RESUMO

OBJECTIVE: To investigate the correlation between bone metabolism markers, bone mineral density (BMD), and sarcopenia. METHODS: A total of 331 consecutive patients aged ≥ 60 years who were hospitalized between November 2020 and December 2021 were enrolled. Participants were divided into sarcopenia and non-sarcopenia groups according to the Asian Working Group on Sarcopenia criteria (AWGS, 2019). The clinical data, bone metabolism markers (ß-CTX, N-MID, and TP1NP), and BMD were compared between the two groups. RESULTS: Age, ß-CTX, and N-MID of the sarcopenia group were higher than those of the non-sarcopenia group (P < 0.05), but the BMD T values were lower than those of the non-sarcopenia group (P < 0.05). Binary logistic regression analysis showed that increased femoral neck BMD (FNBMD) was a protective factor for sarcopenia, while increased ß-CTX was a risk factor. Pearson/Spearman correlation analysis showed that the diagnostic indices of sarcopenia were positively correlated with FNBMD and negatively correlated with ß-CTX and N-MID. Multiple linear regression analysis revealed that BMI and FNBMD significantly positively affected muscle strength and appendicular skeletal muscle mass (ASM). The FNBMD significantly positively affected physical performance, while ß-CTX significantly negatively affected muscle strength, ASM, and physical performance. CONCLUSION: Increased FNBMD may be a protective factor against sarcopenia, and increased ß-CTX may be a risk factor. The FNBMD significantly positively affected the diagnostic indices of sarcopenia, while ß-CTX significantly negatively affected them. BMD and bone metabolism marker levels may be considered in early screening for sarcopenia.


Assuntos
Biomarcadores , Densidade Óssea , Sarcopenia , Humanos , Sarcopenia/diagnóstico , Sarcopenia/metabolismo , Feminino , Masculino , Densidade Óssea/fisiologia , Idoso , Biomarcadores/análise , Pessoa de Meia-Idade , Pró-Colágeno/sangue , Músculo Esquelético/metabolismo , Fragmentos de Peptídeos/sangue , Colágeno Tipo I/sangue , Osso e Ossos/metabolismo , Força Muscular/fisiologia
18.
J Dairy Sci ; 107(5): 3207-3218, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38101736

RESUMO

Heat stress compromises dairy production by decreasing feed intake and milk yield, and it may also alter milk composition and feed efficiency. However, little information is available for evaluating such effects across different levels of heat stress and cows enrolled in heat stress studies. The objectives of this study were to evaluate the effects of heat stress on dry matter intake (DMI), energy-corrected milk (ECM), milk composition, and feed efficiency (kg ECM/kg DMI) and to investigate the relationship between such effects and heat stress intervention and animal characteristics by using meta-analytical approaches. Data from 31 studies (34 trials) fulfilled the inclusion criteria and were used for analysis. Results showed that heat stress decreased DMI, ECM, and milk protein concentration, but did not alter milk fat concentration or feed efficiency. Meta-regression confirmed that such reductions in DMI and ECM were significantly associated with increasing temperature-humidity index (THI). Over the period of heat stress, for each unit increase in THI, DMI and ECM decreased by 4.13% and 3.25%, respectively, in mid-lactation cows. Regression models further revealed the existence of a strong interaction between THI and lactation stage, which partially explained the large heterogeneity in effect sizes of DMI and ECM. The results indicated a need for more research on the relationship between the effect of heat stress and animal characteristics. This study calls for the implementation of mitigation strategies in heat-stressed herds due to the substantial decrease in productivity.


Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Animais , Bovinos , Feminino , Ração Animal/análise , Doenças dos Bovinos/metabolismo , Dieta/veterinária , Ingestão de Alimentos , Ingestão de Energia , Transtornos de Estresse por Calor/metabolismo , Transtornos de Estresse por Calor/veterinária , Lactação , Leite/metabolismo
19.
Int Endod J ; 57(4): 451-463, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38279698

RESUMO

AIM: Rev-erbα has been reported to regulate the healing of inflammatory lesions through its effect on the immune system in a variety of inflammatory disease. Moreover, the balance of macrophages polarization plays a crucial role in immune response and inflammatory progression. However, in refractory periapical periodontitis (RAP), the role of Rev-erbα in inflammatory response and bone resorption by regulating macrophage polarization remains unclarified. The aims of the present study were to investigate the expression of Rev-erbα in experimental RAP and to explore the relationship between Rev-erbα and macrophage polarization through the application of its pharmacological agonist SR9009 into the in vivo and in vitro experiments. METHODOLOGY: Enterococcus faecalis-induced RAP models were established in SD rats. Histological staining and micro-computed tomography scanning were used to evaluate osteoclastogenesis and alveolar bone resorption. The expression of Rev-erbα and macrophage polarization were detected in the periapical tissues from rats by immunofluorescence, flow cytometry, and western blots. Furthermore, immunohistochemical staining and enzyme-linked immunosorbent assay were performed to explore the relationship between Rev-erbα and inflammatory cytokines related to macrophage polarization. RESULT: Compared to healthy periapical tissue, the expression of Rev-erbα was significantly down-regulated in macrophages from inflammatory periapical area, especially in Enterococcus faecalis-induced periapical lesions, with obvious type-1 macrophage (M1)-like dominance and the production of pro-inflammatory cytokines. In addition, Rev-erbα activation by SR9009 could induce type-2 macrophage (M2)-like polarization in periapical tissue and THP1 cell line, followed by increased secretion of anti-inflammatory cytokines IL-10 and TGF-ß. Furthermore, intracanal application of SR9009 reduced the lesion size and promoted the repair of RAP by decreasing the number of osteoclasts and enhancing the formation of mineralized tissue in periapical inflammatory lesions. CONCLUSIONS: Rev-erbα played an essential role in the pathogenesis of RAP through its effect on macrophage polarization. Targeting Rev-erbα might be a promising and prospective therapy method for the prevention and management of RAP.


Assuntos
Reabsorção Óssea , Periodontite Periapical , Pirrolidinas , Tiofenos , Ratos , Animais , Microtomografia por Raio-X , Ratos Sprague-Dawley , Citocinas
20.
Public Health ; 229: 13-23, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382177

RESUMO

OBJECTIVES: This study aimed to examine the psychometric properties of the P4 suicide screener in a multinational sample. The primary goal was to evaluate the reliability and validity of the scale and investigate its convergent validity by analyzing its correlation with depression, anxiety, and substance use. STUDY DESIGN: The study design is a cross-sectional self-report study conducted across 42 countries. METHODS: A cross-sectional, self-report study was conducted in 42 countries, with a total of 82,243 participants included in the final data set. RESULTS: The study provides an overview of suicide ideation rates across 42 countries and confirms the structural validity of the P4 screener. The findings indicated that sexual and gender minority individuals exhibited higher rates of suicidal ideation. The P4 screener showed adequate reliability, convergence, and discriminant validity, and a cutoff score of 1 is recommended to identify individuals at risk of suicidal behavior. CONCLUSIONS: The study supports the reliability and validity of the P4 suicide screener across 42 diverse countries, highlighting the importance of using a cross-cultural suicide risk assessment to standardize the identification of high-risk individuals and tailoring culturally sensitive suicide prevention strategies.


Assuntos
Comparação Transcultural , Ideação Suicida , Humanos , Estudos Transversais , Psicometria , Reprodutibilidade dos Testes , Prevenção do Suicídio
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