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1.
Risk Manag Healthc Policy ; 16: 1703-1718, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37670732

RESUMEN

Purpose: This study aims to investigate the impact of the Chinese New Year (CNY) holiday season on the outcomes of In Vitro Fertilization (IVF) fresh embryo transfer cycles. Participants and Methods: This retrospective study analyzed 4688 patients who received their first IVF fresh cycle attempt between January 2017 and October 2021. Of these, 4449 women underwent IVF during non-holiday seasons, while 239 women were treated during the CNY holiday season. The study included women who underwent IVF treatment during the specified time frame. The primary outcome was the live birth rate (LBR). Results: The study found that the LBR of IVF performed during the CNY holiday season was 32.22%, which is significantly lower than that of the non-holiday season (43.38%, p<0.001). Multivariate logistic regression analysis showed that the CNY holiday season (OR=0.62, 95% CI 0.47-0.82, p=0.001) was an independent factor associated with the live birth rate. Propensity score matching (PSM) data analysis showed that the LBR in the CNY holiday season group was 31.78% compared to 42.64% in the non-holiday season group (p=0.005). Inverse probability of treatment weighting (IPTW) data also indicated that the CNY holiday season had a lower LBR than the non-holiday season (OR=0.64, 95% CI 0.47-0.87, p=0.005). Conclusion: IVF performed during the CNY holiday season results in a lower live birth rate, potentially indicating that certain lifestyle adjustments during this period, such as unhealthy dietary, tobacco and alcohol usage, sleep disruption, and emotional stress experienced could have some influence on the outcomes.

2.
J Multidiscip Healthc ; 16: 2781-2792, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37753342

RESUMEN

Objective: For patients with polycystic ovary syndrome (PCOS) to undergo in vitro fertilization (IVF) and embryo transfer (ET), there has been no consensus regarding which protocol is the most optimal for live birth rate in fresh cycles. We sought to evaluate depot gonadotropin-releasing hormone (GnRH) agonist protocol versus GnRH antagonist protocol in IVF outcomes for PCOS patients in a single fertility center. Methods: In this retrospective cohort, PCOS patients who visited the Second Hospital of Hebei Medical University reproductive center between February 2012 and December 2019 were screened, and 533 PCOS infertility patients were included undergoing their first IVF cycle, with 470 in the depot GnRH agonist group and 63 in the GnRH antagonist group. The primary of this study outcome was the fresh live birth rate (LBR). Results: PCOS women in the depot GnRH agonist group had a higher LBR (49.79%) than those in the GnRH antagonist group (34.92%, p = 0.027). The multivariable logistic regression also confirmed that women in the depot GnRH agonist group had a higher LBR than those in the GnRH antagonist group (OR = 1.83, 95% CI 1.05~3.18, p = 0.032). After propensity score matching (PSM), the LBR in the depot GnRH agonist group was higher (50.32%) than that of the GnRH antagonist group (35.48%), p = 0.033. The ovarian hyperstimulation syndrome (OHSS) rates were similar between the two groups, with 35 in the depot GnRH group and 6 in the GnRH antagonist group (p = 0.561). Conclusions: For PCOS patients in fresh embryo transfer cycles, the depot GnRH agonist protocol may lead to a higher LBR than the antagonist protocol with satisfied lower OHSS rates.

3.
Front Med (Lausanne) ; 8: 735318, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34859005

RESUMEN

Purpose: To evaluate the treatment solutions and effectiveness of intravitreal ranibizumab (RBZ) or conbercept in patients with wet age-related macular degeneration (wAMD) in a real-life setting in China. Methods: The medical records of 368 patients with wAMD who started RBZ or conbercept treatment between 1 May 2014 and 30 April 2018 were evaluated. All patients were defined on fundus angiography at baseline to determine the subtype of AMD (PCV or CNV). We report visual acuity (VA) and central retinal thickness (CRT) measurements at baseline and 12 months. Results: The average number of anti-VEGF injections was 2.1 ± 1.2. The BCVA improvement of these two groups was similar with a difference of 1.00 letter (95% CI: -1.4~3.4, p = 0.8505). At the end of the study, a BCVA increase of at least 5 letters was determined to be a satisfactory efficacy endpoint. Several factors were related to the possible improvement in the satisfactory efficacy endpoint, including female sex (OR 2.07, 95% CI 1.22~3.51), number of injections (OR 1.40, 95% CI 1.12~1.75) and VA change at the first month (OR 13.75, 95% CI 7.41~25.51). Additionally, some factors were related to the possible reduction in the satisfactory efficacy endpoint, including diabetes (OR 0.27, 95% CI 0.10~0.73) and disease history (OR 0.75, 95% CI 0.57~0.98). Conclusion: Our study demonstrates that anti-VEGF drugs can effectively improve BCVA and reduce CRT in AMD patients. Sex, number of injections, VA change at the first month, diabetes and disease history are the most important factors affecting visual acuity.

4.
J Alzheimers Dis ; 80(3): 1257-1267, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33646151

RESUMEN

BACKGROUND: A valid, reliable, accessible, engaging, and affordable digital cognitive screen instrument for clinical use is in urgent demand. OBJECTIVE: To assess the clinical utility of the MemTrax memory test for early detection of cognitive impairment in a Chinese cohort. METHODS: The 2.5-minute MemTrax and the Montreal Cognitive Assessment (MoCA) were performed by 50 clinically diagnosed cognitively normal (CON), 50 mild cognitive impairment due to AD (MCI-AD), and 50 Alzheimer's disease (AD) volunteer participants. The percentage of correct responses (MTx-% C), the mean response time (MTx-RT), and the composite scores (MTx-Cp) of MemTrax and the MoCA scores were comparatively analyzed and receiver operating characteristic (ROC) curves generated. RESULTS: Multivariate linear regression analyses indicated MTx-% C, MTx-Cp, and the MoCA score were significantly lower in MCI-AD versus CON and in AD versus MCI-AD groups (all with p≤0.001). For the differentiation of MCI-AD from CON, an optimized MTx-% C cutoff of 81% had 72% sensitivity and 84% specificity with an area under the curve (AUC) of 0.839, whereas the MoCA score of 23 had 54% sensitivity and 86% specificity with an AUC of 0.740. For the differentiation of AD from MCI-AD, MTx-Cp of 43.0 had 70% sensitivity and 82% specificity with an AUC of 0.799, whereas the MoCA score of 20 had 84% sensitivity and 62% specificity with an AUC of 0.767. CONCLUSION: MemTrax can effectively detect both clinically diagnosed MCI and AD with better accuracy as compared to the MoCA based on AUCs in a Chinese cohort.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Disfunción Cognitiva/diagnóstico , Diagnóstico Precoz , Pruebas de Estado Mental y Demencia , Anciano , Enfermedad de Alzheimer/complicaciones , Pueblo Asiatico , Disfunción Cognitiva/etiología , Estudios de Cohortes , Femenino , Humanos , Masculino , Sensibilidad y Especificidad
5.
Front Endocrinol (Lausanne) ; 12: 728051, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35111134

RESUMEN

Objective: To assess whether women of advanced age (≥35 years) with polycystic ovary syndrome (PCOS) have the same cumulative live birth rate (CLBR) as their age-matched controls with tubal factor infertility and to determine the influencing factors on the CLBRs of aged women. Design: A retrospective cohort study. Setting and Population: A total of 160 women of advanced age (≥35 years) with PCOS and 1073 women with tubal factor infertility were included in our study. All patients underwent their first fresh cycles and subsequent frozen cycles within in one year in our centre from 2015 to 2020. Methods: To determine independent influencing factors on the CLBRs of these aged patients, a multivariable Cox regression model of CLBR according to the transfer cycle type was constructed. Main outcome measure(s): CLBRs. Result: The Cox regression model of the CLBRs indicated that there was no significant difference between the PCOS group and the tubal infertility group in terms of advanced age (HR, 0.95; 95% CI, 0.71-1.27, P=0.732). The CLBR significantly decreased for women of advanced reproductive age up to 37 years of age (HR, 0.46; 95% CI, 0.39-0.56, P<0.001). The CLBR increased by 63% when more than ten oocytes were retrieved (HR, 1.63; 95% CI, 1.34-1.98, P<0.001). Patients with an AMH level above 32.13pmol/l were likely to have a 72%(HR, 1.72; 95% CI, 1.08-2.73, = 0.023) and 34% (HR, 1.34; 95% CI, 1.07-1.68, P=0.010)improvement in CLBR compared to those with an AMH below 7.85pmol/l and 7.85-32.12pmol/l, respectively. Conclusion: Despite the higher number of oocytes retrieved in PCOS patients, the reproductive window is not extended for PCOS patients compared with tubal factor infertility patients. Age, AMH and the number of oocytes retrieved play crucial roles in the CLBRs of patients of advanced age (≥35 years).


Asunto(s)
Infertilidad Femenina/terapia , Nacimiento Vivo/epidemiología , Síndrome del Ovario Poliquístico/terapia , Índice de Embarazo , Adulto , Hormona Antimülleriana/metabolismo , Estudios de Casos y Controles , Estudios de Cohortes , Transferencia de Embrión , Enfermedades de las Trompas Uterinas/complicaciones , Femenino , Fertilización In Vitro , Humanos , Infertilidad Femenina/etiología , Infertilidad Femenina/metabolismo , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/metabolismo , Embarazo , Estudios Retrospectivos , Inyecciones de Esperma Intracitoplasmáticas , Resultado del Tratamiento
6.
J Clin Hypertens (Greenwich) ; 22(7): 1247-1252, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32618435

RESUMEN

Hypertensive retinopathy refers to the retinal vascular changes associated with systemic arterial hypertension. Hypertensive retinopathy can be divided into chronic and acute phases. A cross-sectional study was performed to explore a method of measurement in the diameters of retinal vessels for diagnosis of chronic hypertensive retinopathy based on spectral domain optical coherence tomography (SD-OCT). The central retinal artery diameter (CRAD), the central retinal vein diameter (CRVD), and the artery-to-vein ratio (AVR) were measured. A total of 119 subjects with 119 eyes were included in this study, in which 56 subjects with 56 eyes were included in hypertensive group and 63 subjects with 63 eyes were included in normotensive group. There were significant differences between the two groups in the CRAD (t = -2.14, P = .04) and the AVR (t = -2.59, P = .01). The cutoff point of 0.75 was determined by receiver operating characteristic (ROC) curve (area under the curve, AUC 0.786; 95% confidence interval, 95% CI 0.70-0.87). Multivariate logistic regression analysis showed the probability of AVR below to 0.75 was more in patients with high systolic blood pressure (odds ratio OR 4.39; P = .048), more in male (OR 4.15; P = .004) and more in smokers (OR 5.80; P = .01). Bland-Altman plots showed small mean bias between the measurements of the two technicians in the CRAD, the CRVD, and the AVR. In summary, application of SD-OCT is an accurate, reproducible, convenient method for measuring the diameters of retinal vessels. It is valuable for the diagnosis of chronic stage of hypertensive retinopathy.


Asunto(s)
Retinopatía Hipertensiva , Anciano , Estudios Transversales , Femenino , Humanos , Retinopatía Hipertensiva/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Vasos Retinianos , Tomografía de Coherencia Óptica
7.
Proc Natl Acad Sci U S A ; 116(28): 14349-14357, 2019 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-31239335

RESUMEN

Endocytosis is essential to all eukaryotes, but how cargoes are selected for internalization remains poorly characterized. Extracellular cargoes are thought to be selected by transmembrane receptors that bind intracellular adaptors proteins to initiate endocytosis. Here, we report a mechanism for clathrin-mediated endocytosis (CME) of extracellular lanthanum [La(III)] cargoes, which requires extracellular arabinogalactan proteins (AGPs) that are anchored on the outer face of the plasma membrane. AGPs were colocalized with La(III) on the cell surface and in La(III)-induced endocytic vesicles in Arabidopsis leaf cells. Superresolution imaging showed that La(III) triggered AGP movement across the plasma membrane. AGPs were then colocalized and physically associated with the µ subunit of the intracellular adaptor protein 2 (AP2) complexes. The AGP-AP2 interaction was independent of CME, whereas AGP's internalization required CME and AP2. Moreover, we show that AGP-dependent endocytosis in the presence of La(III) also occurred in human cells. These findings indicate that extracellular AGPs act as conserved CME cargo receptors, thus challenging the current paradigm about endocytosis of extracellular cargoes.


Asunto(s)
Endocitosis/genética , Galactanos/metabolismo , Lantano/farmacología , Metales de Tierras Raras/farmacología , Proteínas Adaptadoras Transductoras de Señales/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales/genética , Membrana Celular/efectos de los fármacos , Clatrina/química , Endocitosis/efectos de los fármacos , Galactanos/genética , Humanos , Lantano/química , Lantano/metabolismo , Metales de Tierras Raras/química , Metales de Tierras Raras/metabolismo , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo
8.
Pestic Biochem Physiol ; 156: 36-43, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31027579

RESUMEN

Declines in honey bee populations represent a worldwide concern. The widespread use of neonicotinoid insecticides has been one of the factors linked to these declines. Sublethal doses of a neonicotinoid insecticide, imidacloprid, has been reported to cause olfactory learning deficits in honey bees via impairment of the target organ, the brain. In the present study, olfactory learning of honey bees was compared between controls and imidacloprid-treated bees. The brains of imidacloprid-treated and control bees were used for comparative transcriptome analysis by RNA-Seq to elucidate the effects of imidacloprid on honey bee learning capacity. The results showed that the learning performance of imidacloprid-treated bees was significantly impaired in comparison with control bees after chronic oral exposure to imidacloprid (0.02 ng/µl) for 11 days. Gene expression profiles between imidacloprid treatment and the control revealed that 131 genes were differentially expressed, of which 130 were downregulated in imidacloprid-treated bees. Validation of the RNA-Seq data using qRT-PCR showed that the results of qRT-PCR and RNA-Seq exhibited a high level of agreement. Gene ontology annotation indicated that the oxidation-reduction imbalance might exist in the brain of honey bees due to oxidative stress induced by imidacloprid exposure. KEGG and ingenuity pathway analysis revealed that transient receptor potential and Arrestin 2 in the phototransduction pathway were significantly downregulated in imidacloprid-treated bees, and that five downregulated genes have causal effects on behavioral response inhibition in imidacloprid-treated bees. Our results suggest that downregulation of brain genes involved in immune, detoxification and chemosensory responses may result in decreased olfactory learning capabilities in imidacloprid-treated bees.


Asunto(s)
Insecticidas/farmacología , Neonicotinoides/farmacología , Nitrocompuestos/farmacología , Animales , Abejas , Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Oxidación-Reducción/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Transcriptoma/genética
9.
Front Plant Sci ; 10: 153, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30842782

RESUMEN

Rare earth elements [REE(III)] increasingly accumulate in the atmosphere and can be absorbed by plant leaves. Our previous study showed that after treatment of REE(III) on plant, REE(III) is first bound by some extracellular molecules of plant cells, and then the endocytosis of leaf cells will be initiated, which terminates the endocytic inertia of leaf cells. Identifying the extracellular molecules for binding REE(III) is the crucial first step to elucidate the mechanism of REE(III) initiating the endocytosis in leaf cells. Unfortunately, the molecules are unknown. Here, cerium(III) [Ce(III)] and Arabidopsis served as a representative of REE(III) and plants, respectively. By using interdisciplinary methods such as confocal laser scanning microscopy, immune-Au and fluorescent labeling, transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy, circular dichroism spectroscopy, fluorescent spectrometry and molecular dynamics simulation, we obtained two important discoveries: first, the arabinogalactan proteins (AGP) inside leaf cells were sensitively increased in protein expression and recruited onto the plasma membrane; second, to verify whether AGP can bind to Ce(III) in the acidic environment outside leaf cells, by choosing fasciclin-like AGP11 (AtFLA11) as a representative of AGP, we found that Ce(III) can form stable [Ce(H2O)7](III)-AtFLA11 complexes with an apparent binding constant of 1.44 × 10-6 in simulated acidic environment outside leaf cells, in which the secondary and tertiary structure of AtFLA11 was changed. The structural change in AtFLA11 and the interaction between AtFLA11 and Ce(III) were enhanced with increasing the concentration of Ce(III). Therefore, AtFLA11 can serve as Lewis bases to coordinately bind to Ce(III), which broke traditional chemical principle. The results confirmed that AGP can be the possible extracellular molecules for binding to exogenous Ce(III) outside leaf cells, and provided references for elucidating the mechanism of REE(III) initiating the endocytosis in leaf cells.

10.
J Inorg Biochem ; 182: 158-169, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29482161

RESUMEN

After rare earth elements [REE(III)] are anchored outside of the plasma membrane, REE(III) break plant evolution to initiate leaf cell endocytosis, which finally affects plant growth. However, the molecule for anchoring REE(III) in the acidic environment outside of the plasma membrane is not clear, which is crucial for exploring the mechanism of REE(III) breaking plant evolution. Here, lanthanum(III) [La(III)] and terbium(III) [Tb(III)] were respectively served as a representative of REE(III) without and with f electrons, and Arabidopsis was served as a representative of plants, cellular and molecular basis for arabinogalactan proteins (AGP) anchoring REE(III) outside of the plasma membrane was investigated. By using interdisciplinary methods, when REE(III) initiated leaf cell phagocytosis, we observed the increase in the expression of AGP and their migration to the outside of the plasma membrane. In the acidic environment outside of the plasma membrane, Tb(III) formed more stable Lewis acid-base [REE(III)-AGP] complexes with a higher apparent binding constant (1.51 × 10-6) than La(III) (1.24 × 10-6). In REE(III)-AGP complexes, the bond lengths of REE(III)-O were in normal range and H-bonds were strong H-bonds. The formation of REE(III)-AGP complexes sequentially disturbed the secondary and tertiary structure of AGP, which were enhanced with increasing the concentration of REE(III), and Tb(III) caused stronger structural changes than La(III). Hence, AGP could be molecules for anchoring REE(III) outside of the plasma membrane. The results of this study are direct imaging of how lanthanides break the normal evolution of plants, and can serve as an important guidance for investigating mechanism of lanthanides in organisms.


Asunto(s)
Elementos de la Serie de los Lantanoides/metabolismo , Plantas/metabolismo , Membrana Celular/metabolismo , Mucoproteínas/metabolismo , Proteínas de Plantas/metabolismo
11.
Pestic Biochem Physiol ; 140: 1-8, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28755688

RESUMEN

Acute toxicities (LD50s) of imidacloprid and clothianidin to Apis mellifera and A. cerana were investigated. Changing patterns of immune-related gene expressions and the activities of four enzymes between the two bee species were compared and analyzed after exposure to sublethal doses of insecticides. Results indicated that A. cerana was more sensitive to imidacloprid and clothianidin than A. mellifera. The acute oral LD50 values of imidacloprid and clothianidin for A. mellifera were 8.6 and 2.0ng/bee, respectively, whereas the corresponding values for A. cerana were 2.7 and 0.5ng/bee. The two bee species possessed distinct abilities to mount innate immune response against neonicotinoids. After 48h of imidacloprid treatment, carboxylesterase (CCE), prophenol oxidase (PPO), and acetylcholinesterase (AChE) activities were significantly downregulated in A. mellifera but were upregulated in A. cerana. Glutathione-S-transferase (GST) activity was significantly elevated in A. mellifera at 48h after exposure to imidacloprid, but no significant change was observed in A. cerana. AChE was downregulated in both bee species at three different time points during clothianidin exposure, and GST activities were upregulated in both species exposed to clothianidin. Different patterns of immune-related gene expression and enzymatic activities implied distinct detoxification and immune responses of A. cerana and A. mellifera to imidacloprid and clothianidin.


Asunto(s)
Abejas/efectos de los fármacos , Guanidinas/toxicidad , Insecticidas/toxicidad , Neonicotinoides/toxicidad , Nitrocompuestos/toxicidad , Tiazoles/toxicidad , Animales , Guanidinas/química , Antígenos de Histocompatibilidad , Insecticidas/química , Neonicotinoides/química , Nitrocompuestos/química , Especificidad de la Especie , Tiazoles/química
12.
Ecotoxicol Environ Saf ; 145: 227-234, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28738206

RESUMEN

Vitronectin-like protein (VN) is widely found outside plant plasma membranes. The VN molecular surface contains a large number of active groups that combine strongly with rare earth elements (REEs), which means that VN is a preferential binding target for REEs exhibiting their toxic effects, but the toxicological mechanism remains unknown. This study used transmission electron microscopy, circular dichroism, fluorescence spectrometry, ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy, and calculational chemistry (homology modeling, molecular dynamics simulation and quantum chemical calculation) to preliminarily investigate the effect of lanthanum [La(III)] as an REE, on the structure of VN and its toxicological mechanism. The results showed that low-concentration La(III) could cause micro-interference to the VN molecular structure through weak interactions, such as electrostatic attraction. High-concentration La(III) formed stable complexes with VN, which changed the average binding energy and electron cloud density of VN, loosened the molecular structure and increased the disorder of VN molecule. The results of building a 3D model of VN and simulating the interaction between La(III) and VN using calculational chemistry showed that La(H2O)73+ in solution could coordinately bind to the carboxyl-/carbonyl-O groups in the negatively charged areas on the VN molecular surface. Furthermore, one or more strong H-bonds were formed to enhance the stability of the La(H2O)73+-VN complexes. In summary, low La(III) concentrations could cause micro-interference to the VN molecular structure, whereas high La(III) concentrations could coordinately bind to VN to form stable La-VN complexes, which destroyed the molecular structure of VN; thus the toxicological basis by which La(III) exhibits its toxic effects is its binding to VN.


Asunto(s)
Arabidopsis/metabolismo , Lantano/toxicidad , Proteínas de Plantas/metabolismo , Contaminantes del Suelo/toxicidad , Vitronectina/metabolismo , Arabidopsis/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Dicroismo Circular , Lantano/química , Simulación de Dinámica Molecular , Proteínas de Plantas/química , Unión Proteica , Conformación Proteica , Teoría Cuántica , Contaminantes del Suelo/química , Espectrometría de Fluorescencia , Vitronectina/química
13.
Environ Pollut ; 230: 902-910, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28738302

RESUMEN

The environmental safety of cerium (Ce) applications in many fields has been debated for almost a century because the cellular effects of environmental Ce on living organisms remain largely unclear. Here, using new, interdisciplinary methods, we surprisingly found that after Ce(III) treatment, Ce(III) was first recognized and anchored on the plasma membrane in leaf cells. Moreover, some trivalent Ce(III) was oxidized to tetravalent Ce(IV) in this organelle, which activated pinocytosis. Subsequently, more anchoring sites and stronger valence-variable behavior on the plasma membrane caused stronger pinocytosis to transport Ce(III and IV) into the leaf cells. Interestingly, a great deal of Ce was bound on the pinocytotic vesicle membrane; only a small amount of Ce was enclosed in the pinocytotic vesicles. Some pinocytic vesicles in the cytoplasm were deformed and broken. Upon breaking, pinocytic vesicles released Ce into the cytoplasm, and then these Ce particles self-assembled into nanospheres. The aforementioned special behaviors of Ce decreased the fluidity of the plasma membrane, inhibited the cellular growth of leaves, and finally, decreased plant yield. In summary, our findings directly show the special cellular behavior of Ce in plant cells, which may be the cellular basis of plant yield reduction induced by environmental Ce.


Asunto(s)
Cerio/toxicidad , Pinocitosis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Membrana Celular , Cerio/metabolismo
14.
Chemosphere ; 181: 690-698, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28476009

RESUMEN

The wide applications cause a large amount of rare earth elements (REEs) to be released into the environment, and ultimately into the human body through food chain. Toxic effects of REEs on humans have been extensively studied, but their toxic effects and binding targets in cells are not understood. Delayed outward potassium channels (K+ channels) are good targets for exogenous substances or clinical drugs. To evaluate cellular toxicities of REEs and clarify toxic mechanisms, the toxicities of REEs on the K+ channel and their structural basis were investigated. The results showed that delayed outward potassium channels on the plasma membrane are the targets of REEs acting on living organisms, and the changes in the thermodynamic and kinetic characteristics of the K+ channel are the reasons of diseases induced by REEs. Two types of REEs, a light REE La3+ and a heavy REE Tb3+, displayed different intensity of toxicities on the K+ channel, in which the toxicity of Tb3+ was stronger than that of La3+. More interestingly, in comparison with that of heavy metal Cd2+, the cytotoxicities of the light and heavy REEs showed discriminative differences, and the cytotoxicity of Tb3+ was higher than that of Cd2+, while the cytotoxicity of La3+ was lower than that of Cd2+. These different cytotoxicities of La3+, Tb3+ and Cd2+ on human resulted from the varying binding abilities of the metals to this channel protein.


Asunto(s)
Canal de Potasio ERG1/efectos de los fármacos , Metales de Tierras Raras/toxicidad , Cadmio/metabolismo , Cadmio/toxicidad , Membrana Celular/metabolismo , Ambiente , Células HEK293 , Humanos , Lantano/metabolismo , Lantano/toxicidad , Metales Pesados/metabolismo , Metales de Tierras Raras/química , Unión Proteica , Terbio/metabolismo , Terbio/toxicidad , Transfección
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