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1.
Nat Chem Biol ; 19(5): 585-595, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36635566

RESUMEN

The cell-cycle checkpoint kinase WEE1 is emerging as a therapeutic target for cancer treatment. However, how its catalytic activity is regulated remains poorly understood, and reliable biomarkers for predicting response to WEE1 inhibitor remain to be identified. Here we identify an evolutionarily conserved segment surrounding its Lys177 residue that inhibits WEE1 activity through an intermolecular interaction with the catalytic kinase domain. Upon DNA damage, CHK1-dependent phosphorylation of WEE1 at Ser642 primes GCN5-mediated acetylation at Lys177, resulting in dissociation of the inhibitory segment from the kinase domain and subsequent activation of WEE1 and cell-cycle checkpoints. Conversely, SIRT1 associates with and deacetylates WEE1, which maintains it in an inactive state. Consequently, SIRT1 deficiency induces WEE1 hyperacetylation and activation, rendering cancer cells resistant to WEE1 inhibition. These results suggest that SIRT1 expression level and abundance of WEE1 Lys177 acetylation in tumor cells can serve as useful biomarkers for predicting WEE1 inhibitor sensitivity or resistance.


Asunto(s)
Proteínas de Ciclo Celular , Neoplasias , Proteínas de Ciclo Celular/metabolismo , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Línea Celular Tumoral , Sirtuina 1/genética , Daño del ADN , Biomarcadores , Neoplasias/tratamiento farmacológico , Neoplasias/genética
2.
Ann Hematol ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809457

RESUMEN

Reduced-toxicity conditioning (RIC) regimens are used for allogeneic hematopoietic stem cell transplantation in older patients. However, successful outcomes are hindered by graft-versus-host disease (GVHD), treatment-related mortality, and relapse, particularly after haploidentical donor hematopoietic stem cell transplantation (HID-HSCT). The aim of this study was to evaluate the effectiveness of an RIC conditioning regimen that included a combination of cyclosporin A, methotrexate (on day + 1), mycophenolate, lower doses of post-transplantation PTCy (40 mg/kg on day + 3), and ATG (7.5 mg/kg) as GVHD prophylaxis prior to haplo-stem cell transplantation (haplo-SCT) in older patients. METHODS: We retrospectively analyzed outcomes in 55 patients ≥ 55 years of age with hematologic malignancies treated with fludarabine, cytarabine, busulfan, and low-dose cyclophosphamide as the conditioning regimen between January 1, 2019, and November 30, 2023. RESULTS: Neutrophil engraftment was successful in all patients within 28 days, with 54 patients (98.2%) achieving complete donor chimerism. The cumulative incidence of non-relapse mortality was 0% at 30 days, 7.5% at 100 days, and 19% at 1 year. The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) was 25% (95%CI, 15-38%), whereas that of grade III-IV aGVHD was 9.1% (95% CI, 3.3-19%). The cumulative incidence of extensive chronic graft-versus-host disease at 1 year was 3.6% (95%CI, 0.66-11%). The cumulative incidences of relapse, overall survival, and GVHD-free/relapse-free survival at 1 year were 9.0%, 71.6%, and 67.1%, respectively. CONCLUSIONS: An RIC conditioning regimen, including a combination of lower PTCy/ATG as GVHD prophylaxis, followed by haplo-SCT, might be a promising option for appropriately selected older patients.

3.
Oral Dis ; 30(2): 551-561, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36648372

RESUMEN

OBJECTIVE: The present study identified potentially pivotal miRNAs contributing to chondrogenic differentiation in temporomandibular joint suffering abnormal stress. MATERIALS AND METHODS: Sprague-Dawley rats were randomly divided into control and experimental unilateral mastication (EUM) group. Bone micro-structure parameters was detected by micro-CT, and FGF-1 and MMP-1 expression was examined by immunohistochemistry. Differentially expressed miRNAs of bilateral condyle cartilage were screened via miRNA microarray at 4- and 8-week EUM, then further verified using quantitative reverse-transcription PCR. Over-expression of five differentially expressed miRNAs in chondrocytes was triggered by transfecting miRNA mimics. The expression of MMP-13, Col-II, OPN, and Runx2 was verified by western blotting. RESULTS: Expressions of FGF-1 and MMP-1 in right condyles gradually increased from 2 to 6 weeks after EUM. A total of 20 differentially expressed miRNAs were regulated by EUM, which related to cell proliferation, invasion, and osteoblast differentiation pathways. The over-expression of miR-148a-3p and miR-1-3p led to down-regulation of Col-II, while MMP-13 and Runx2 were up-regulated by induction of hypotrophic differentiation or IL-1ß stimulation. These findings suggested that miR-148a-3p and miR-1-3p promote chondrogenic differentiation. CONCLUSIONS: Several pivotal miRNAs were found to be related to chondrogenic differentiation, which provides novel insight into pathogenic mechanisms of cartilage homeostasis.


Asunto(s)
MicroARNs , Ratas , Animales , MicroARNs/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal , Metaloproteinasa 13 de la Matriz/genética , Metaloproteinasa 1 de la Matriz , Factor 1 de Crecimiento de Fibroblastos , Masticación , Ratas Sprague-Dawley , Cartílago/metabolismo , Homeostasis
4.
Nucleic Acids Res ; 50(10): 5672-5687, 2022 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-35640614

RESUMEN

Replication fork reversal occurs via a two-step process that entails reversal initiation and reversal extension. DNA topoisomerase IIalpha (TOP2A) facilitates extensive fork reversal, on one hand through resolving the topological stress generated by the initial reversal, on the other hand via its role in recruiting the SUMO-targeted DNA translocase PICH to stalled forks in a manner that is dependent on its SUMOylation by the SUMO E3 ligase ZATT. However, how TOP2A activities at stalled forks are precisely regulated remains poorly understood. Here we show that, upon replication stress, the SUMO-targeted ubiquitin E3 ligase RNF4 accumulates at stalled forks and targets SUMOylated TOP2A for ubiquitination and degradation. Downregulation of RNF4 resulted in aberrant activation of the ZATT-TOP2A-PICH complex at stalled forks, which in turn led to excessive reversal and elevated frequencies of fork collapse. These results uncover a previously unidentified regulatory mechanism that regulates TOP2A activities at stalled forks and thus the extent of fork reversal.


Asunto(s)
Replicación del ADN , Inestabilidad Genómica , Replicación del ADN/genética , Inestabilidad Genómica/genética , Humanos , Proteínas Nucleares/metabolismo , Sumoilación , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
5.
BMC Public Health ; 24(1): 723, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448849

RESUMEN

BACKGROUND: Deep learning (DL), a specialized form of machine learning (ML), is valuable for forecasting survival in various diseases. Its clinical applicability in real-world patients with gastric cancer (GC) has yet to be extensively validated. METHODS: A combined cohort of 11,414 GC patients from the Surveillance, Epidemiology and End Results (SEER) database and 2,846 patients from a Chinese dataset were utilized. The internal validation of different algorithms, including DL model, traditional ML models, and American Joint Committee on Cancer (AJCC) stage model, was conducted by training and testing sets on the SEER database, followed by external validation on the Chinese dataset. The performance of the algorithms was assessed using the area under the receiver operating characteristic curve, decision curve, and calibration curve. RESULTS: DL model demonstrated superior performance in terms of the area under the curve (AUC) at 1, 3, and, 5 years post-surgery across both datasets, surpassing other ML models and AJCC stage model, with AUCs of 0.77, 0.80, and 0.82 in the SEER dataset and 0.77, 0.76, and 0.75 in the Chinese dataset, respectively. Furthermore, decision curve analysis revealed that the DL model yielded greater net gains at 3 years than other ML models and AJCC stage model, and calibration plots at 3 years indicated a favorable level of consistency between the ML and actual observations during external validation. CONCLUSIONS: DL-based model was established to accurately predict the survival rate of postoperative patients with GC.


Asunto(s)
Aprendizaje Profundo , Neoplasias Gástricas , Humanos , Algoritmos , Área Bajo la Curva , Pueblo Asiatico , Neoplasias Gástricas/cirugía , Pueblos de América del Norte
6.
Chaos ; 34(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38526978

RESUMEN

Turbulent bursting events have been classified into outward interactions (Q1), ejections (Q2), inward interactions (Q3), and sweeps (Q4) in various studies. Ejections (Q2) and sweeps (Q4) have been identified as significant contributors to time consumption, momentum flux, and sediment flux. Additionally, research has shown that the distribution of these events varies nonuniformly at different bed elevations. Despite extensive investigations into the nonuniform distribution of turbulent bursting events, their impact on sediment transport has been rarely explored. In this work, we developed a modified stochastic diffusion particle tracking model (SD-PTM) driven by skew Brownian motion (SBM) using the stochastic Lagrangian approach to scrutinize sediment particle movement in turbulent flows. The model incorporates turbulent characteristics derived from a direct numerical simulation dataset, allowing for a comprehensive analysis of sediment particle dynamics. Moreover, the proposed model accounts for the nonuniform spatial distribution of ejection and sweep events, as well as the particle movement direction during these events. Numerical simulations of the model were conducted to trace sediment particle trajectories in the streamwise and vertical directions. The analysis of sediment transport involved calculating the variance of particle trajectories to examine anomalous diffusion. The model's performance was evaluated by comparing it with flow velocity and sediment concentration profiles obtained from measurements in previous studies. In conclusion, our study suggests that the motion of sediment particles in turbulent flow can be thoroughly investigated under extreme flow conditions using the modified SD-PTM driven by SBM.

7.
BMC Bioinformatics ; 24(1): 278, 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37415176

RESUMEN

MOTIVATION: Accurate identification of Drug-Target Interactions (DTIs) plays a crucial role in many stages of drug development and drug repurposing. (i) Traditional methods do not consider the use of multi-source data and do not consider the complex relationship between data sources. (ii) How to better mine the hidden features of drug and target space from high-dimensional data, and better solve the accuracy and robustness of the model. RESULTS: To solve the above problems, a novel prediction model named VGAEDTI is proposed in this paper. We constructed a heterogeneous network with multiple sources of information using multiple types of drug and target dataIn order to obtain deeper features of drugs and targets, we use two different autoencoders. One is variational graph autoencoder (VGAE) which is used to infer feature representations from drug and target spaces. The second is graph autoencoder (GAE) propagating labels between known DTIs. Experimental results on two public datasets show that the prediction accuracy of VGAEDTI is better than that of six DTIs prediction methods. These results indicate that model can predict new DTIs and provide an effective tool for accelerating drug development and repurposing.


Asunto(s)
Desarrollo de Medicamentos , Reposicionamiento de Medicamentos , Interacciones Farmacológicas
8.
Opt Lett ; 48(16): 4408-4411, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37582044

RESUMEN

In this paper, an artificial-intelligence-based secure semantic optical communication scheme is proposed. The semantic features of the original text information are extracted using Transformer. Compared with other networks, Transformer reduces the complexity of the structure and the associated training cost by using the multi-head attention mechanism. To solve the security problem, the encryption scheme is applied to an orthogonal frequency division multiplexed passive optical network (OFDM-PON). The proposed scheme applies chaotic sequences to produce masking vectors. We encrypt the constellation and frequency, achieving a large key space of 1 × 10270. To prove that Transformer can effectively extract the semantic features of text, we have computed the values of ROUGE-1, ROUGE-2, and ROUGE-L, which are 40.9, 18.02, and 37.17, respectively. An encrypted 16 quadrature amplitude modulation (16QAM) OFDM signal transmission over a 2 km seven-core fiber with a data rate of 78.5 Gbits/s was experimentally demonstrated. During the experiments, the bit error rate (BER) was analyzed and the results show that the proposed system improves efficiency and security in an OFDM-PON system.

9.
Oral Dis ; 2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37660361

RESUMEN

OBJECTIVE: To investigate and explain the beneficial effects of local intra-articular injection of Salubrinal on temporomandibular joint osteoarthritis (TMJOA) using a rabbit model of anterior disc displacement (ADD). METHODS: Rabbits were divided and subjected to surgical ADD. Salubrinal was administered by intra-articular injection in the TMJ every other day for 2 and 4 weeks after operation. Histological examination and TUNEL staining were then performed. Immunohistochemistry, quantitative real-time PCR, and Western blot analysis were employed to evaluate the expression of endoplasmic reticulum (ER) stress-related markers, catabolic factors, extracellular matrix proteins, inflammatory factors, and nuclear factor-kappa B (NF-κB) activation. RESULTS: In the ADD groups, we found that Salubrinal partly reversed condylar cartilage deterioration according to the histological analysis. Salubrinal reduced chondrocytes apoptosis while increased matrix components including Collagen II and Aggrecan. Meanwhile, Salubrinal downregulated the catabolic expression of MMP13, ADAMTS5, VEGF, TNF-α, and IL-1ß. We also observed that Salubrinal inhibited ER stress activation by reducing the expression of GRP78, CHOP, ATF4, and Caspase-12. Additionally, Salubrinal suppressed the phosphorylation of NF-κB. CONCLUSION: These results indicate that Salubrinal alleviates cartilage degradation following ADD, suggesting that intra-articular injection of Salubrinal is a potential therapeutic approach for preventing TMJOA.

10.
Food Microbiol ; 112: 104242, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36906324

RESUMEN

Contaminations of pathogenic and spoilage microbes on foods are threatening food safety and quality, highlighting the importance of developing antimicrobial agents. According to different working mechanisms, the antimicrobial activities of yeast-based agents were summarized from two aspects: antagonism and encapsulation. Antagonistic yeasts are usually applied as biocontrol agents for the preservation of fruits and vegetables via inactivating spoilage microbes, usually phytopathogens. This review systematically summarized various species of antagonistic yeasts, potential combinations to improve the antimicrobial efficiency, and the antagonistic mechanisms. The wide applications of the antagonistic yeasts are significantly limited by undesirable antimicrobial efficiency, poor environmental resistance, and a narrow antimicrobial spectrum. Another strategy for achieving effective antimicrobial activity is to encapsulate various chemical antimicrobial agents into a yeast-based carrier that has been previously inactivated. This is accomplished by immersing the dead yeast cells with porous structure in an antimicrobial suspension and applying high vacuum pressure to allow the agents to diffuse inside the yeast cells. Typical antimicrobial agents encapsulated in the yeast carriers have been reviewed, including chlorine-based biocides, antimicrobial essential oils, and photosensitizers. Benefiting from the existence of the inactive yeast carrier, the antimicrobial efficiencies and functional durability of the encapsulated antimicrobial agents, such as chlorine-based agents, essential oils, and photosensitizers, are significantly improved compared with the unencapsulated ones.


Asunto(s)
Antiinfecciosos , Aceites Volátiles , Saccharomyces cerevisiae , Cloro , Fármacos Fotosensibilizantes , Frutas
11.
BMC Infect Dis ; 22(1): 465, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35570276

RESUMEN

BACKGROUND: There is no consensus on the optimal secondary antifungal prophylaxis (SAP) regimen in patients receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT). The purpose of this study was to evaluate the efficacy and safety of posaconazole oral suspension as secondary prophylaxis of invasive fungal disease (IFD) for allo-HSCT patients. METHODS: We retrospectively reviewed clinical data from prior IFD patients who received posaconazole oral suspension as systemic antifungal prophylaxis between June 2016 and January 2021 and have a follow-up period of 1 year after HSCT. The clinical outcomes of patients with a prior history of IFD (n = 30) and those without (n = 93) were compared. RESULTS: The 1-year cumulative incidence of prophylaxis failure was 58.3% in the group with prior history of IFD and 41.6% in the group without a prior history of IFD (p = 0.459). The cumulative incidence of proven, probable or possible IFD within 1 year after allo-HSCT was 23.1% in the group with prior history of IFD and 14.1% in the group without prior history of IFD (p = 0.230). There was no significant difference between the cumulative incidence of proven or probable IFD within 1-year after allo-HSCT in the group with a prior history of IFD and the group without (p = 0.807). Multivariate logistic regression revealed cytomegalovirus disease as risk factor for post-transplantation IFD occurrence in posaconazole oral suspension prophylaxis. There was not a significant difference in overall survival between the patients with IFD history and those without (P = 0.559). CONCLUSIONS: Our study support that allo-HSCT recipients with a prior history of IFD and normal GI absorption can choose posaconazole oral suspension as a safe and effective SAP option.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Infecciones Fúngicas Invasoras , Antifúngicos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Infecciones Fúngicas Invasoras/etiología , Infecciones Fúngicas Invasoras/prevención & control , Estudios Retrospectivos , Triazoles/uso terapéutico
12.
Oral Dis ; 28(8): 2239-2247, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34342085

RESUMEN

OBJECTIVES: Many activities overload temporomandibular joint (TMJ) and cause mandibular condylar cartilage (MCC) degradation by inducing the expression of hypoxia-inducible factor-2α (HIF-2α). Although NF-κB signaling pathway has been reported to induce HIF-2α expression, the underlying mechanisms need to be verified. The aim was to investigate the effects of NF-κB/HIF-2α on MCC degradation induced by mechanical stress and the regulatory mechanism of NF-κB in the HIF-2α pathway. METHODS: Chondrocytes were subjected to cyclic compressive forces in a hypoxic environment. Western blotting was used to test the effects of stress on the expression of NF-κB and HIF-2α. HIF-2α siRNA and shRNA were constructed and transfected into MCC cells in vitro and in vivo to inhibit HIF-2α expression. To test the regulatory effect of the NF-κB pathway on HIF-2α, siRNA p65 was transfected into MCC. RESULTS: The results showed that mechanical stress could cause cartilage degradation and significantly increased the expression of NF-κB, HIF-2α, and downstream degradation factors (MMP13 and ADAMTs-4). Blockade of HIF-2α decreased cartilage degradation and related degradation factors. Suppression of p65 significantly decreased the expression of HIF-2α. CONCLUSIONS: Our results indicated that the upstream NF-κB pathway exerted a regulatory effect on HIF-2α in the degradation of MCC induced by stress.


Asunto(s)
FN-kappa B , Osteoartritis , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Condrocitos/metabolismo , Humanos , Metaloproteinasa 13 de la Matriz/metabolismo , FN-kappa B/metabolismo , Osteoartritis/genética , Osteoartritis/metabolismo , ARN Interferente Pequeño/metabolismo , Estrés Mecánico , Articulación Temporomandibular
13.
Chaos ; 32(8): 081104, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36049906

RESUMEN

We investigate evolving dynamics of cyclically competing species on spatially extended systems with considering a specific region, which is called the "wildlife refuge," one of the institutional ways to preserve species biodiversity. Through Monte-Carlo simulations, we found that the refuge can play not groundbreaking but an important role in species survival. Species coexistence is maintained at a moderate mobility regime, which traditionally leads to the collapse of coexistence, and eventually, the extinction is postponed depending on the competition rate rather than the portion of the refuge. Incorporating the extinction probability and Fourier transform supported our results in both stochastic and analogous ways. Our findings may provide valuable evidence to assist fields of ecological/biological sciences in understanding the presence and construction of refuges for wildlife with associated effects on species biodiversity.


Asunto(s)
Animales Salvajes , Ecosistema , Animales , Biodiversidad , Modelos Biológicos , Probabilidad
14.
Chaos ; 32(9): 093116, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36182385

RESUMEN

Recognizing surrounding situations, such as enemy attacks, which can be realized by predator-prey relationships, is one of the common behaviors of the population in ecosystems. In this paper, we explore the relationship between such species' behavior and biodiversity in the spatial rock-paper-scissors game by employing the ecological concept "vigilance." In order to describe the vigilance process, we adopt a multiplex structure where two distinct layers describe virtual and physical interactions. By investigating the process of evolution in species, we also found that species with different vigilance go together. In addition, by utilizing the dynamic time warping method, we found that species with the same vigilance have consistent behavior, but species with different vigilance have diverse behavior. Our findings may lead to broader interpretations of mechanisms promoting biodiversity via vigilance in species ecosystems.


Asunto(s)
Biodiversidad , Ecosistema , Teoría del Juego , Dinámica Poblacional
15.
Sensors (Basel) ; 22(14)2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35890887

RESUMEN

Global Navigation Satellite System (GNSS) signals generate slant tropospheric delays when they pass through the atmosphere, which is recognized as the main source of error in many spatial geodetic applications. The zenith tropospheric delay (ZTD) derived from radio occultation data is of great significance to atmospheric research and meteorology and needs to be assessed in the use of precision positioning. Based on the atmPrf, sonPrf, and echPrf data from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) Data Analysis and Archiving Center (CDAAC) from 1 January to 31 December 2008 and 2012, we obtained the ZTDs of the radio occultation data (occZTD) and the corresponding radiosonde (sonZTD) and ECWMF data (echZTD). The ZTDs derived from ground-based global positioning system (GPS) observations from the International GNSS Service (IGS) were corrected to the lowest tangent point height of the matched radio occultation profile by the barometric height formula (gnsZTD). The statistical results show that the absolute values of the bias between occZTD and echZTD, sonZTD, or gnsZTD are less than 5 mm, and the standard deviations are approximately 20 mm or less, indicating that occZTD had significant accuracy in the GNSS positioning model even when the local spherical symmetry assumption error was introduced when the Abel inversion algorithm was used to obtain the refractive index profile of atmPrf. The effects of the horizontal/vertical matching resolution and the variation in the station height/latitude on the biases of occZTD and gnsZTD were analyzed. The results can be used to quantify the performance of radio occultation data for tropospheric delay error correction in dynamic high-precision positioning.

16.
J Environ Sci (China) ; 115: 47-54, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34969475

RESUMEN

Different aggregates vary in their ability to retain or adsorb metals in soil. Five soil profiles were sampled from different soil horizons and grouped, and the concentrations of Al, Mg, Ca, Fe, Mn, Cd, Cu and Pb were determined in six sizes of aggregates (> 2, 2-1, 1-0.6, 0.6-0.25, 0.25-0.053, < 0.053 mm). Significantly high (p < 0.05) structural stability indexes (SSI) and aggregate stability indexes (ASI) were recorded in the topsoil horizon, which may be attributed to the high soil organic matter (SOM) content in aggregates from topsoil. In addition, ASI and SSI were positively correlated (r = 0.569, p < 0.05) with each other, which indicated that the stability of soil aggregates could contribute to the structural stability of bulk soil. Moreover, accumulation factors (AF), principal component analysis (PCA) and Pearson's correlation coefficients were used for metal element assessment. The results indicated that SOM was not a key factor affecting the accumulation of Ca, Mg, Al, Fe, Mn, Pb, Cd and Cu in soil aggregates. In general, AF values for metal elements in microaggregates (< 0.25 mm) were high, which showed that metals preferred to accumulate in fine soil aggregates. The PCA and Pearson's correlation coefficients indicated that soil parent materials primarily controlled the distribution of Al, Ca, Fe, Mg and Mn, while materials derived from technogenic sources have important impacts on the distribution of Cd, Cu and Pb in soil aggregates along the soil profile.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , China , Monitoreo del Ambiente , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisis
17.
J Environ Sci (China) ; 119: 78-92, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35934468

RESUMEN

Mercury (Hg) could be microbially methylated to the bioaccumulative neurotoxin methylmercury (MeHg), raising health concerns. Understanding the methylation of various Hg species is thus critical in predicting the MeHg risk. Among the known Hg species, mercury sulfide (HgS) is the largest Hg reservoir in the lithosphere and has long been considered to be highly inert. However, with advances in the analytical methods of nanoparticles, HgS nanoparticles (HgS NPs) have recently been detected in various environmental matrices or organisms. Furthermore, pioneering laboratory studies have reported the high bioavailability of HgS NPs. The formation, presence, and transformation (e.g., methylation) of HgS NPs are intricately related to several environmental factors, especially dissolved organic matter (DOM). The complexity of the behavior of HgS NPs and the heterogeneity of DOM prevent us from comprehensively understanding and predicting the risk of HgS NPs. To reveal the role of HgS NPs in Hg biogeochemical cycling, research needs should focus on the following aspects: the formation pathways, the presence, and the environmental behaviors of HgS NPs impacted by the dominant influential factor of DOM. We thus summarized the latest progress in these aspects and proposed future research priorities, e.g., developing the detection techniques of HgS NPs and probing HgS NPs in various matrices, further exploring the interactions between DOM and HgS NPs. Besides, as most of the previous studies were conducted in laboratories, our current knowledge should be further refreshed through field observations, which would help to gain better insights into predicting the Hg risks in natural environment.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Nanopartículas , Mercurio/química , Metilación , Compuestos de Metilmercurio/metabolismo , Nanopartículas/química , Nanopartículas/toxicidad , Sulfuros
18.
J Environ Sci (China) ; 119: 152-165, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35934460

RESUMEN

The transformation of mercury (Hg) in the environment plays a vital role in the cycling of Hg and its risk to the ecosystem and human health. Of particular importance are Hg oxidation/reduction and methylation/demethylation processes driven or mediated by the dynamics of light, microorganisms, and organic carbon, among others. Advances in understanding those Hg transformation processes determine our capacity of projecting and mitigating Hg risk. Here, we provide a critical analysis of major knowledge gaps in our understanding of Hg transformation in nature, with perspectives on approaches moving forward. Our analysis focuses on Hg transformation processes in the environment, as well as emerging methodology in exploring these processes. Future avenues for improving the understanding of Hg transformation processes to protect ecosystem and human health are also explored.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Ecosistema , Humanos , Metilación
19.
BMC Psychiatry ; 21(1): 363, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-34284741

RESUMEN

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic profoundly impacts on mental health, yet it is still unclear whether COVID-19 distress makes people more vulnerable to suicidal behavior. The present study aims to examine the association between COVID-19 related psychological distress and risk for suicide attempt, and moderators of this association, among hotline callers. METHODS: This case-control study was conducted at the largest psychological support hotline in China. Hotline callers who sought help for psychological distress and reported whether or not they attempted suicide in the last 2 weeks (recent suicide attempt) were analyzed. The primary predictor of recent suicide attempt was the presence or absence of COVID-19 related psychological distress. Demographic variables and common risk and protective factors for suicidal behavior were also studied. Callers with COVID-19 related distress (COVID-19 callers) and those without such distress (non-COVID-19 callers) were compared on these variables. Recent suicide attempt was regressed on COVID-19 related distress and the other variables, and significant interaction terms of aforementioned predictors by COVID-19 related distress, to identify variables that moderate the association of COVID-19 related distress and recent suicide attempt. RESULTS: Among 7337 included callers, there were 1252 COVID-19 callers (17.1%) and 6085 non-COVID-19 callers (82.9%). The COVID-19 callers were less likely to report recent suicide attempt (n = 73, 5.8%) than the non-COVID-19 callers (n = 498, 8.2%, P = 0.005). The COVID-19 callers were also less likely to have high scores on depressive symptoms (22.6% vs 26.3%, P < 0.001) and psychological distress (19.5% vs 27.3%, P < 0.001), and were more likely to have high hopefulness scores (46.5% vs 38.0%, P < 0.001). Tests of moderating effects showed that acute life events were associated with one-half lower risk (P = 0.021), and a trend that suicide attempt history was associated with two-thirds greater risk (P = 0.063) for recent suicide attempt, among COVID-19 callers than non-COVID-19 callers. CONCLUSIONS: The COVID-19 calls are from individuals with lower suicide-related risk compared to more typical callers. Acute stressful life events provided a key context for suicide attempt in non-COVID-19 callers, i.e., more typical calls.


Asunto(s)
COVID-19 , Distrés Psicológico , Estudios de Casos y Controles , China/epidemiología , Líneas Directas , Humanos , SARS-CoV-2 , Intento de Suicidio
20.
Clin Oral Implants Res ; 32(2): 180-191, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33220090

RESUMEN

OBJECTIVES: To compare clinical and radiographic outcomes between transcrestal sinus floor elevation (TSFE) and lateral sinus floor elevation (LSFE) approaches of simultaneous implant placement in atrophic maxilla. MATERIALS AND METHODS: Patients with a residual bone height (RBH) ≤6 mm were enrolled and randomly assigned to TSFE and LSFE groups. Patients in both groups simultaneously underwent sinus floor elevation with bovine-derived xenograft and implant placement. Clinical and radiographic results were evaluated immediately after surgery and after 6, 12, 18, and 24 months. The endo-sinus bone gain (ESBG), apical implant bone height (ABH), endo-sinus bone-implant contact rate (EBICR), and crestal bone level (CBL) were assessed using panoramic radiographs. RESULTS: Forty-one implants (TSFE: 21, LSFE: 20) were placed in cases with a mean RBH of 3.77 ± 1.16 mm. All implants obtained clinical success and satisfactory ESBG at 24 months. No significant differences were found in ESBG and ABH between two groups immediately after surgery, but LSFE group showed significantly higher values than TSFE group thereafter. Grafts in TSFE group reached stability 6 months earlier than that in LSFE group. In both groups, EBICR was almost 100%, and CBL showed no detectable changes. CONCLUSIONS: LSFE can achieve higher ESBG 2 years after surgery. Otherwise, TSFE could be an alternative to LSFE, when the access for lateral window preparation is limited. Both approaches were highly predictable for RBH ≤6 mm during 24-month observation period for the implants placed simultaneously.


Asunto(s)
Implantes Dentales , Elevación del Piso del Seno Maxilar , Senos Transversos , Implantación Dental Endoósea , Humanos , Maxilar/cirugía , Seno Maxilar/cirugía , Estudios Prospectivos , Resultado del Tratamiento
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