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1.
J Chem Phys ; 160(20)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38775245

RESUMO

Halide perovskite nanocrystals are at the forefront of materials research due to their remarkable optoelectronic properties and versatile applications. While their lattice structure and optical properties have been extensively investigated for the structure-property correlation, their lattice dynamics, the physical link between the lattice structure and optoelectronic properties, has been much less visited. We report the evolution of structural dynamics of a series of cesium lead halide perovskite nanocrystals whose size and morphology are systematically varied by synthesis temperature. Low-frequency Raman spectroscopy uncovers the nanocrystals' structural dynamics, including a relaxational spectral continuum from ligand librations and a phonon spectrum evolving with nanocrystal size. As the size of nanocrystals increases, their phonon spectrum becomes more intense, and their spectral weights redistribute with new first- and second-order modes being activated. The linewidth of the observed phonon modes generally broadens as the nanocrystal grows larger, an interesting deviation from the established phonon confinement model. We suggest that strong confinement and truncation of the lattice and ligands anchoring on the surface might lead to pinning of the lattice dynamics at nanoscale. These findings offer new insights into the bulk-nano-transition in halide perovskite soft semiconductors.

2.
BMC Urol ; 24(1): 5, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172816

RESUMO

OBJECTIVES: The aim of this study was to use deep learning (DL) of intraoperative images of urinary stones to predict the composition of urinary stones. In this way, the laser frequency and intensity can be adjusted in real time to reduce operation time and surgical trauma. MATERIALS AND METHODS: A total of 490 patients who underwent holmium laser surgery during the two-year period from March 2021 to March 2023 and had stone analysis results were collected by the stone laboratory. A total of 1658 intraoperative stone images were obtained. The eight stone categories with the highest number of stones were selected by sorting. Single component stones include calcium oxalate monohydrate (W1), calcium oxalate dihydrate (W2), magnesium ammonium phosphate hexahydrate, apatite carbonate (CH) and anhydrous uric acid (U). Mixed stones include W2 + U, W1 + W2 and W1 + CH. All stones have intraoperative videos. More than 20 intraoperative high-resolution images of the stones, including the surface and core of the stones, were available for each patient via FFmpeg command screenshots. The deep convolutional neural network (CNN) ResNet-101 (ResNet, Microsoft) was applied to each image as a multiclass classification model. RESULTS: The composition prediction rates for each component were as follows: calcium oxalate monohydrate 99% (n = 142), calcium oxalate dihydrate 100% (n = 29), apatite carbonate 100% (n = 131), anhydrous uric acid 98% (n = 57), W1 + W2 100% (n = 82), W1 + CH 100% ( n = 20) and W2 + U 100% (n = 24). The overall weighted recall of the cellular neural network component analysis for the entire cohort was 99%. CONCLUSION: This preliminary study suggests that DL is a promising method for identifying urinary stone components from intraoperative endoscopic images. Compared to intraoperative identification of stone components by the human eye, DL can discriminate single and mixed stone components more accurately and quickly. At the same time, based on the training of stone images in vitro, it is closer to the clinical application of stone images in vivo. This technology can be used to identify the composition of stones in real time and to adjust the frequency and energy intensity of the holmium laser in time. The prediction of stone composition can significantly shorten the operation time, improve the efficiency of stone surgery and prevent the risk of postoperative infection.


Assuntos
Cálculos Renais , Cálculos Urinários , Humanos , Oxalato de Cálcio , Cálculos Renais/diagnóstico por imagem , Cálculos Renais/cirurgia , Ácido Úrico , Apatitas , Aprendizado de Máquina , Carbonatos
3.
Urol Int ; 108(2): 100-107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38081150

RESUMO

INTRODUCTION: Bladder cancer (BC) is a major health concern that poses a significant threat to the population, with an increasing incidence rate and a high risk of recurrence and progression. The primary clinical method for diagnosing BC is cystoscopy, but due to the limitations of traditional white light cystoscopy and inadequate clinical experience among junior physicians, its detection rate for bladder tumor, especially small and flat lesions, is relatively low. However, recent years have seen remarkable advancements in the application of artificial intelligence (AI) technology in the field of medicine. This has led to the development of numerous AI algorithms that have been successfully integrated into medical practices, providing valuable assistance to clinicians. The purpose of this study is to develop a cystoscopy algorithm that is real time, cost effective, high performing, and accurate, with the aim of enhancing the detection rate of bladder tumors during cystoscopy. MATERIALS AND METHODS: For this study, a dataset of 3,500 cystoscopic images obtained from 100 patients diagnosed with BC was collected, and a deep learning model was developed utilizing the U-Net algorithm within a convolutional neural network for training purposes. RESULTS: This study randomly divided 3,500 images from 100 BC patients into training and validation groups, and each patient's pathology result was confirmed. In the validation group, the accuracy of tumor recognition by the U-Net algorithm reached 98% compared to primary urologists, with greater accuracy and faster detection speed. CONCLUSION: This study highlights the potential of U-Net-based deep learning techniques in the detection of bladder tumors. The establishment and optimization of the U-Net model is a significant breakthrough and it provides a valuable reference for future research in the field of medical image processing.


Assuntos
Inteligência Artificial , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Cistoscopia/métodos , Redes Neurais de Computação , Algoritmos
4.
J Appl Toxicol ; 42(6): 1016-1028, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34970773

RESUMO

Emerging evidence suggests that selenium plays an essential role in sperm maturation. However, the specific signaling pathway by which selenium exerts effect has not been elucidated. To evaluate the effect of selenium on GPX4-mediated lipid peroxidation and apoptosis in germ cells, selenium deficiency was modeled by culturing GC2-spd cells in serum-free medium. Treatment with 0.5-µM sodium selenite (NaSe) or 5.0-µM selenomethionine (SeMet) significantly improved the proliferation rate and GPX4 protein expression after selenium deficiency. Moreover, NaSe and SeMet decreased the MDA content and lipid peroxidation. When adenovirus was used to knockdown the expression of the GPX4 gene (shRNA-GPX4), the early apoptosis rate of the shRNA-GPX4 cells was significantly higher than that of the EGFP cells. Increased expression of Caspase3 and Bax, as well as MDA content were observed in the shRNA-GPX4 cells compared with EGFP cells. In further, overexpression of the GPX4 gene (ORF-GPX4) cells exhibited increased cell proliferation and decreased MDA content. However, there was no significant difference in 12/15-lox expression both in ORF-GPX4 cells and shRNA-GPX4 cells. Conclusively, GPX4 was involved in the regulation of lipid peroxidation and apoptosis in GC2-spd cells. Selenium played a role in promoting cell proliferation by mediating GPX4. The regulation of GPX4 may occur independently of 12/15-Lox. These findings confirmed the effect of selenium on spermatogenesis and offered a potential target for treating abnormal semen quality in men.


Assuntos
Selênio , Antioxidantes/metabolismo , Apoptose , Células Germinativas/metabolismo , Humanos , Peroxidação de Lipídeos , Masculino , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , RNA Interferente Pequeno/metabolismo , Selênio/metabolismo , Selênio/farmacologia , Selenometionina , Análise do Sêmen
5.
Environ Res ; 182: 109004, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31835114

RESUMO

Triclosan (TCS), as a widely used antimicrobial compound, is commonly detected in pregnant women and newborns indicating exposure risk during early development. However, whether perinatal TCS exposure has long-term effects on the host microbiome which further contributes to metabolic disorder is still unclear. The long-term effects of perinatal TCS exposure on gut microbiota and liver metabolism in adulthood and old age were investigated. Rats were given 0, 10 or 50 mg TCS/kg body weight per day, administered daily by gavage from gestation day 0 until lactation day 21. RNA-sequencing and 16 S rDNA amplicon sequencing analysis were performed to explore the potential mechanisms. Increased blood glucose and serum HDL-C were observed at 10 mg/kg/day in old rats and at 50 mg/kg/day in both adult and old rats. Serum leptin were increased at two doses in old rats. Serum TG and LDL-C were increased at two doses in both adult and old rats. Hepatic glycogen were decreased at 50 mg/kg/day in adult rats and at two doses in old rats. Increased hepatic TG were observed at two doses in old rats. Hepatic RNA-sequencing revealed that more differentially expressed genes were found at 50 mg/kg/day in both adult and old rats. More up-regulated genes in pathways of carbohydrate and lipid metabolism were observed in old rats at 50 mg/kg/day. Diversity reduction and compositional alteration were found in gut microbiota at 50 mg/kg/day in adult rats and at two doses in old rats. These effects lasted for a long time even without TCS exposure and accumulated over time inducing metabolic disorder in old rat offspring. TCS exposure during early life causes disturbances in metabolism and gut microbiota which last a lifetime and accumulated over time at 50 mg/kg/day. Further research is needed to investigate the effects of early life TCS exposure on metabolism and gut microbiota in humans.


Assuntos
Poluentes Ambientais , Microbioma Gastrointestinal , Metabolismo dos Lipídeos , Triclosan , Adulto , Animais , Poluentes Ambientais/toxicidade , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Recém-Nascido , Lactação , Fígado , Gravidez , Ratos , Triclosan/toxicidade
6.
J Cell Mol Med ; 23(1): 167-176, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30499219

RESUMO

Spleen tyrosine kinase (SYK) gene has been identified as novel susceptibility locus for ischaemic stroke (IS) previously. However, regulation of SYK gene remains unknown in IS. In this study, we aimed to identify miRNAs that might be involved in the development of IS by targeting SYK gene. miRNAs were firstly screened by bioinformatics predicting tool. The expression levels of SYK gene were detected by qRT-PCR and western blotting, respectively, after miRNA transfection. Luciferase reporter assay was applied to investigate the direct binding between miRNAs and target gene. miRNA levels were detected by miRNA TaqMan assays in the blood cells of 270 IS patients and 270 control volunteers. Results suggest that SYK gene might be a direct target of miR-129-2-3p. The blood level of miR-129-2-3p was significantly lower in IS patients (P < 0.05), and negatively associated with the risk of IS (adjusted OR: 0.88; 95% CI: 0.80-0.98; P = 0.021) by multivariable logistic regression analysis. The blood levels of SYK gene were significantly higher in IS patients, and miR-129-2-3p expression was negatively correlated with mean platelet volume. In summary, our study suggests that miR-129-2-3p might be involved in the pathogenesis of IS through interrupting SYK expression and the platelet function, and further investigation is needed to explore the underlying mechanism.


Assuntos
Isquemia Encefálica/genética , MicroRNAs/genética , Acidente Vascular Cerebral/genética , Quinase Syk/genética , Regiões 3' não Traduzidas , Idoso , Povo Asiático/genética , Isquemia Encefálica/sangue , Estudos de Casos e Controles , Linhagem Celular , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Volume Plaquetário Médio , Pessoa de Meia-Idade , Acidente Vascular Cerebral/sangue , Quinase Syk/sangue
7.
Ecotoxicol Environ Saf ; 176: 1-10, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30903973

RESUMO

Wide use of titanium dioxide nanoparticles (TiO2 NPs) as white pigments induces unintentionally release in environment which increases concerns about their adverse health effects on respiratory system. So it is crucial to get a deep understanding of the disease process and molecular mechanism. Epigenetic mechanisms, such as DNA methylation, have been found to play a role in the development of lung diseases by affecting expression of key genes. In addition, there could be potential different toxic effects of TiO2 NPs between young and adult. Thus, the comparative toxicity of TiO2 NPs in 5-week (young) and 10-week (adult) old NIH mice is investigated in this study following nasal inhalation of TiO2 NPs at dose of 20 mg/kg (body weight)/day for 30 days. Global DNA methylation and hydroxymethylation in lung were measured. Promoter methylation of inflammatory genes (IFN-γ and TNF-α) and tissue fibrosis gene (Thy-1) were determined. Additional, RNA-sequencing runs were performed on the pulmonic libraries. We found the induced pulmonary inflammation and fibrosis were more severe in young mice. Decreased global methylation and hydroxymethylation were only found in the young group. The altered methylation in promoter of TNF-α and Thy-1 were found to play a role in the inflammatory response and fibration. RNA-sequencing showed that in pathways in cancer expression of 197 genes was up-regulated in the young mice more that in the adult mice. All these results suggested that the young ages are more sensitive to TiO2 NP exposure and the potential of abnormal DNA methylation might be used as biomarkers of both exposure and disease development.


Assuntos
Metilação de DNA , Exposição por Inalação , Pulmão/efeitos dos fármacos , Nanopartículas/toxicidade , Pneumonia/patologia , Titânio/toxicidade , Animais , Biomarcadores/metabolismo , Fibrose/genética , Pulmão/patologia , Nanopartículas Metálicas/toxicidade , Camundongos , Pneumonia/genética , Regiões Promotoras Genéticas , Análise de Sequência de RNA , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
8.
Nano Lett ; 18(1): 460-466, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29268017

RESUMO

Electrochemical intercalation is a powerful method for tuning the electronic properties of layered solids. In this work, we report an electrochemical strategy to controllably intercalate lithium ions into a series of van der Waals (vdW) heterostructures built by sandwiching graphene between hexagonal boron nitride (h-BN). We demonstrate that encapsulating graphene with h-BN eliminates parasitic surface side reactions while simultaneously creating a new heterointerface that permits intercalation between the atomically thin layers. To monitor the electrochemical process, we employ the Hall effect to precisely monitor the intercalation reaction. We also simultaneously probe the spectroscopic and electrical transport properties of the resulting intercalation compounds at different stages of intercalation. We achieve the highest carrier density >5 × 1013 cm2 with mobility >103 cm2/(V s) in the most heavily intercalated samples, where Shubnikov-de Haas quantum oscillations are observed at low temperatures. These results set the stage for further studies that employ intercalation in modifying properties of vdW heterostructures.

9.
J Am Chem Soc ; 140(38): 12001-12009, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30063832

RESUMO

Jarosite, a mineral with a kagomé lattice, displays magnetic frustration yet orders magnetically below 65 K. As magnetic frustration can engender exotic physical properties, understanding the complex magnetism of jarosite comprises a multidecade interdisciplinary challenge. Unraveling the nature of the disparate magnetic coupling interactions that lead to magnetic order in jarosite remains an open question. Specifically, there is no observed trend in the interlayer spacing with magnetic order. Similarly, the relationship between metal-ligand bond distance and magnetic order remains uninvestigated. Here, we use applied pressure to smoothly vary jarosite's structure without manipulating the chemical composition, enabling a chemically invariant structure-function study. Using single-crystal and powder X-ray diffraction, we show that high applied pressures alter both the interlayer spacing and the metal-ligand bond distances. By harnessing a suite of magnetic techniques under pressure, including SQUID-based magnetometry, time-resolved synchrotron Mössbauer spectroscopy, and X-ray magnetic circular dichroism, we construct the magnetic phase diagram for jarosite up to 40 GPa. Notably, we demonstrate that the magnetic ordering temperature increases dramatically to 240 K at the highest pressures. Additionally, we conduct X-ray emission spectroscopy, Mössbauer spectroscopy, and UV-visible absorption spectroscopy experiments to comprehensively map the magnetic and electronic structures of jarosite at high pressure. We use these maps to construct chemically pure magnetostructural correlations which fully explain the nature and role of the disparate magnetic coupling interactions in jarosite.

10.
Nano Lett ; 17(12): 7761-7766, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29119791

RESUMO

Modulation of weak interlayer interactions between quasi-two-dimensional atomic planes in the transition metal dichalcogenides (TMDCs) provides avenues for tuning their functional properties. Here we show that above-gap optical excitation in the TMDCs leads to an unexpected large-amplitude, ultrafast compressive force between the two-dimensional layers, as probed by in situ measurements of the atomic layer spacing at femtosecond time resolution. We show that this compressive response arises from a dynamic modulation of the interlayer van der Waals interaction and that this represents the dominant light-induced stress at low excitation densities. A simple analytic model predicts the magnitude and carrier density dependence of the measured strains. This work establishes a new method for dynamic, nonequilibrium tuning of correlation-driven dispersive interactions and of the optomechanical functionality of TMDC quasi-two-dimensional materials.

11.
Biochem Biophys Res Commun ; 489(1): 48-55, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28528975

RESUMO

Ischemic stroke (IS) is characterized by high morbidity and poor prognosis. However, the mechanisms of IS induced injury are still poorly understood. The main aim of this study is to explore the role of autophagy in IS. Ten pairs of whole blood samples of IS patients and matched controls were included to select differential expressed genes (DE genes) by autophagy-related functional gene microarray analysis. And then, one hundred and fifty pairs of whole blood samples of IS patients and matched controls were included to validate the DE genes. Moreover, Gene Ontology (GO) analyses and Pathway analyses were also performed based on the DE gene results. Our results indicated that the co-regulation of autophagy and apoptosis took part in IS-induced injuries, and mitochondrial autophagy and apoptosis played a crucial role in this process. Furthermore, lysosome, protein kinase and endopeptidase also participated in IS. These findings clarified the role of mitochondrial autophagy and apoptosis in ischemic stroke and provided more important biomarkers for the prevention diagnosis and therapeutic implications in IS.


Assuntos
Autofagia/genética , Isquemia Encefálica/genética , Biologia Computacional , Reação em Cadeia da Polimerase , Acidente Vascular Cerebral/genética , Idoso , Isquemia Encefálica/patologia , Estudos de Casos e Controles , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/patologia
12.
Phys Rev Lett ; 118(13): 136001, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28409968

RESUMO

Hybrid lead-halide perovskites have emerged as an excellent class of photovoltaic materials. Recent reports suggest that the organic molecular cation is responsible for local polar fluctuations that inhibit carrier recombination. We combine low-frequency Raman scattering with first-principles molecular dynamics (MD) to study the fundamental nature of these local polar fluctuations. Our observations of a strong central peak in the cubic phase of both hybrid (CH_{3}NH_{3}PbBr_{3}) and all-inorganic (CsPbBr_{3}) lead-halide perovskites show that anharmonic, local polar fluctuations are intrinsic to the general lead-halide perovskite structure, and not unique to the dipolar organic cation. MD simulations indicate that head-to-head Cs motion coupled to Br face expansion, occurring on a few hundred femtosecond time scale, drives the local polar fluctuations in CsPbBr_{3}.

13.
Opt Lett ; 41(22): 5357-5360, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27842131

RESUMO

Optically heterodyne-detected femtosecond Raman-induced Kerr-effect spectroscopy (OHD-FRIKES) was observed in neat cyclohexane. In this Letter, an examination of the effect of the Raman pump ellipticity on the multiplex OHD-FRIKES spectra is discussed. The Raman pump ellipticity scanned OHD-FRIKES results reproduce anomalous observables from previous OHD-FRIKES experiments and suggest new methods of tracking transient vibrational mode polarization in complex systems.

14.
Nano Lett ; 15(8): 5081-8, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26134736

RESUMO

We have investigated the phase transformation of bulk MoS2 crystals from the metastable metallic 1T/1T' phase to the thermodynamically stable semiconducting 2H phase. The metastable 1T/1T' material was prepared by Li intercalation and deintercalation. The thermally driven kinetics of the phase transformation were studied with in situ Raman and optical reflection spectroscopies and yield an activation energy of 400 ± 60 meV (38 ± 6 kJ/mol). We calculate the expected minimum energy pathways for these transformations using DFT methods. The experimental activation energy corresponds approximately to the theoretical barrier for a single formula unit, suggesting that nucleation of the phase transformation is quite local. We also report that femtosecond laser writing converts 1T/1T' to 2H in a single laser pass. The mechanisms for the phase transformation are discussed.


Assuntos
Dissulfetos/química , Molibdênio/química , Transição de Fase , Semicondutores , Cristalização , Análise Espectral Raman , Termodinâmica
15.
Front Public Health ; 12: 1289253, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510362

RESUMO

Introduction: Meteorological and environmental factors can affect people's lives and health, which is crucial among the older adults. However, it is currently unclear how they specifically affect the physical condition of older adults people. Methods: We collected and analyzed the basic physical examination indicators of 41 older adults people for two consecutive years (2021 and 2022), and correlated them with meteorological and environmental factors. Partial correlation was also conducted to exclude unrelated factors as well. Results: We found that among the physical examination indicators of the older adults for two consecutive years, five indicators (HB, WBC, HbAlc, CB, LDL-C) showed significant differences across the population, and they had significantly different dynamic correlation patterns with six meteorological (air pressure, temperature, humidity, precipitation, wind speed, and sunshine duration) and seven air quality factors (NO2, SO2, PM10, O3-1h, O3-8h, CO, PM2.5). Discussion: Our study has discovered for the first time the dynamic correlation between indicators in normal basic physical examinations and meteorological factors and air quality indicators, which will provide guidance for the future development of policies that care for the healthy life of the older adults.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Humanos , Idoso , Poluentes Atmosféricos/análise , Conceitos Meteorológicos , China , Temperatura
16.
Urolithiasis ; 52(1): 40, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427040

RESUMO

This retrospective study aims to examine the correlation between calcium oxalate (CaOx) stones and common clinical tests, as well as urine ionic composition. Additionally, we aim to develop and implement a personalized model to assess the accuracy and feasibility of using charts to predict calcium oxalate stones in patients with urinary tract stones. A retrospective analysis was conducted on data from 960 patients who underwent surgery for urinary stones at the First Affiliated Hospital of Soochow University from January 1, 2010, to December 31, 2022. Among these patients, 447 were selected for further analysis based on screening criteria. Multivariate logistic regression analysis was then performed to identify the best predictive features for calcium oxalate stones from the clinical data of the selected patients. A prediction model was developed using these features and presented in the form of a nomogram graph. The performance of the prediction model was assessed using the C-index, calibration curve, and decision curve, which evaluated its discriminative power, calibration, and clinical utility, respectively. The nomogram diagram prediction model developed in this study is effective in predicting calcium oxalate stones which is helpful in screening and early identification of high-risk patients with calcium oxalate urinary tract stones, and may be a guide for urologists in making clinical treatment decisions.


Assuntos
Líquidos Corporais , Cálculos Urinários , Humanos , Oxalato de Cálcio/química , Estudos Retrospectivos , Nomogramas , Cálculos Urinários/diagnóstico , Cálcio/urina
17.
Artigo em Zh | MEDLINE | ID: mdl-24148947

RESUMO

OBJECTIVE: To investigate the effect of carbon disulfide (CS(2)) on the mitochondrial respiratory chain in testicular spermatogenic cells in male rats and to explore the possible mechanism of reproductive system damage caused by CS(2) in male rats. METHODS: Twenty-four male Sprague-Dawley rats (clean grade) were randomly divided into four groups: three CS(2) exposure groups (CS(2) concentrations: 50, 250, and 1250 mg/m(3)) and a control group. The rats in CS(2) exposure groups were exposed to CS(2) by static inhalation for 10 weeks (2 h/d, 5 d/w), while the rats in control group were exposed to air. Then, all rats were sacrificed by decapitation; testicular tissues were collected, and mitochondrial protein in spermatogenic cells were extracted; the levels of mitochondrial respiratory chain enzyme complex I∼V were measured by enzyme-linked immunosorbent assay. RESULTS: Compared with the control group, all CS(2) exposure groups had significantly increased levels of mitochondrial respiratory chain enzyme complex I∼V in spermatogenic cells (P < 0.05). There were no significant differences in the levels of respiratory chain enzyme complex I∼IV between the CS(2) exposure groups (P < 0.05), but the level of respiratory chain enzyme complex V rose significantly as the concentration of CS(2) increased (P<0.05). CONCLUSION: Various levels of CS(2) exposure may increase the levels of mitochondrial respiratory chain enzyme complex in testicular spermatogenic cells among male rats, thus affecting the normal oxidative phosphorylation in mitochondria.


Assuntos
Dissulfeto de Carbono/toxicidade , Células Germinativas/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Animais , Transporte de Elétrons , Células Germinativas/metabolismo , Masculino , Mitocôndrias/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Artigo em Zh | MEDLINE | ID: mdl-24148948

RESUMO

OBJECTIVE: To investigate the role of mitochondrial pathway in the apoptosis of spermatogenic cells induced by inhalation of carbon disulfide in male rats. METHODS: Twenty-four male Sprague-Dawley rats (clean grade) were divided into four groups according to their body weights: three CS(2) exposure groups (CS(2) concentrations: 50, 250, and 1250 mg/m(3)) and a control group. The rats in CS(2) exposure groups were exposed to CS(2) by static inhalation for 10 weeks (2 h/d, 5 d/w), while the rats in control group were exposed to air. Then, all rats were sacrificed by decapitation; testicular tissues were collected, and cytoplasmic proteins were extracted; the levels of apoptosis-inducing factor (AIF), cytochrome c (cyto c), Bcl-2, Bax, procaspase-9, and procaspase-3 were measured by Western blot, and the activities of caspase-9 and caspase-3 were measured using a test kit. RESULTS: Compared with the control group, all CS(2) exposure groups had significantly increased levels of cyto c in the cytoplasm of testicular tissue (P<0.05); in the 250 mg/m(3) CS(2) exposure group, the Bax/Bcl-2 ratio and activities of caspase-9 and caspase-3 increased significantly (P<0.05), and the content of procaspase-9 and procaspase-3 decreased significantly (P<0.05); in the 1250 mg/m(3) CS(2) exposure group, the relative expression levels of Bax and AIF in cytoplasm increased significantly (P<0.05), and the expression level of Bcl-2 decreased significantly (P<0.05). CONCLUSION: Mitochondrial pathway plays an important role in the CS(2)-induced apoptosis of spermatogenic cells in testicular tissue among male rats.


Assuntos
Apoptose/efeitos dos fármacos , Dissulfeto de Carbono/toxicidade , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Testículo/citologia , Proteína X Associada a bcl-2/metabolismo
19.
Eur J Obstet Gynecol Reprod Biol ; 283: 130-135, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36848763

RESUMO

OBJECTIVE: Triclosan (TCS), a novel endocrine disrupter, has induced widespread human exposure due to its widespread use in personal care products. Environmental TCS exposure was suggested to be associated with human semen quality. However, little is known about seminal plasma TCS concentration and the risk of low sperm quality. This case-control study is established to examine the relationship between seminal plasma TCS and the risk of low sperm quality. STUDY DESIGN: One hundred men with low sperm quality as cases and one hundred normal men as controls were recruited a fertility clinic in Shijiazhuang, China, during 2018-2019. Seminal plasma TCS concentration was determined using an ultrahigh-performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS). Sperm concentration, sperm count, sperm motility and sperm progressive motility were evaluated according to World Health Organization (WHO) guidelines to assess the sperm quality. We used the Mann-Whitney rank-sum test and Kruskal-Wallis test to assess the differences of seminal plasma TCS concentration between the cases and the controls. In addition, logistic regression analysis was used to estimate the associations between seminal plasma TCS concentrations and low sperm quality risk adjusting for age, body mass index (BMI), abstinence time, smoking, and drinking RESULTS AND CONCLUSIONS: The level of seminal plasma TCS was observed slightly but not significantly higher in the case group than the control group. We also observed significant association between seminal plasma TCS concentrations and semen parameters in both control and case groups. Moreover, the seminal plasma TCS levels at the fourth quartile were found to be more likely to exhibit low sperm quality risk with increased adjusted odds ratios of 2.36 (95% confidence interval 1.03-5.39) compared to the first quartile. Our results reveal that seminal plasma TCS concentration was positively associated with low sperm quality risk.


Assuntos
Sêmen , Triclosan , Masculino , Humanos , Análise do Sêmen , Triclosan/efeitos adversos , Estudos de Casos e Controles , Cromatografia Líquida , Motilidade dos Espermatozoides , Espectrometria de Massas em Tandem , Espermatozoides
20.
ACS Nano ; 17(9): 8694-8704, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37093121

RESUMO

[Fe(Htrz)2(trz)](BF4) (Fe-triazole) spin crossover molecules show thermal, electrical, and optical switching between high spin (HS) and low spin (LS) states, making them promising candidates for molecular spintronics. The LS and HS transitions originate from the electronic configurations of Fe(II) and are considered to be diamagnetic and paramagnetic, respectively. The Fe(II) LS state has six paired electrons in the ground states with no interaction with the magnetic field and a diamagnetic behavior is usually observed. While the bulk magnetic properties of Fe-triazole compounds are widely studied by standard magnetometry techniques, their magnetic properties at the individual level are missing. Here we use nitrogen vacancy (NV) based magnetometry to study the magnetic properties of the Fe-triazole LS state of nanoparticle clusters and individual nanorods of size varying from 20 to 1000 nm. Scanning electron microscopy (SEM) and Raman spectroscopy are performed to determine the size of the nanoparticles/nanorods and to confirm their respective spin states. The magnetic field patterns produced by the nanoparticles/nanorods are imaged by NV magnetic microscopy as a function of applied magnetic field (up to 350 mT) and correlated with SEM and Raman. We found that in most of the nanorods the LS state is slightly paramagnetic, possibly originating from the surface oxidation and/or the greater Fe(III) presence along the nanorods' edges. NV measurements on the Fe-triazole LS state nanoparticle clusters revealed both diamagnetic and paramagnetic behavior. Our results highlight the potential of NV quantum sensors to study the magnetic properties of spin crossover molecules and molecular magnets.

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