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1.
Chemosphere ; 345: 140428, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37858765

RESUMO

Persistent organic pollutant perfluorooctane sulfonate (PFOS) is strongly associated with male reproductive disorders, but the related mechanisms are still not fully understood. In this study, we used in vivo and in vitro models to explore the role of organic anion transporting polypeptide 3a1 (Oatp3a1) on PFOS-induced male reproductive injury. Thirty male C57BL/6 (B6) mice were orally given PFOS (0-10 mg/kg/bw) for 28 days. Body weight, organ index, sperm count, histology, and blood-testis barrier (BTB) integrity were evaluated. Primary Sertoli cells were used to describe the related molecular mechanisms of male reproductive injury caused by PFOS. Our results showed that PFOS induced a decrease in sperm count, morphological damage to testicular Sertoli cells, and disruption of BTB. In the in vitro model, exposure to PFOS significantly increased Oatp3a1 mRNA and protein levels and decreased miR-23a-3p expression in Sertoli cells, accompanied by reduced trans-epithelial electrical resistance (TEER) value. By performing the 14C-PFOS uptake experiment, we showed that 14C-PFOS uptake in HEK293-Oatp3a1 cells was apparently higher than in HEK293-MOCK cells. Meanwhile, treating Sertoli cells with Oatp3a1 siRNA significantly decreased Oatp3a1 expression and rescued PFOS-induced decreases in TEER value. As such, the present study highlights that Oatp3a1 may play an important role in the toxic effect of PFOS on Sertoli cells, advancing our understanding of molecular mechanisms for PFOS-induced male reproductive disorders.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Transportadores de Ânions Orgânicos , Masculino , Humanos , Camundongos , Animais , Células de Sertoli , Células HEK293 , Camundongos Endogâmicos C57BL , Sêmen , Ácidos Alcanossulfônicos/metabolismo , Fluorocarbonos/metabolismo , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos/farmacologia
2.
Anal Methods ; 15(29): 3586-3591, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37463001

RESUMO

Amphiphilic aggregation-induced emission (AIE) molecules show superior potential for fabricating novel ultrasmall nanoprobes. Here, an anionic dipyridyl tetraphenylethene (TPE) derivative is rationally designed and a super-small self-assembled AIEgen nanoprobe (TPE-2Py-SO3NaNPs, ca. 2.48 nm) is thus conveniently constructed for the supersensitive detection of protamine and trypsin. In HEPES/DMSO solution (8 : 2, v/v, pH = 7.4), negatively charged TPE-2Py-SO3NaNPs exhibited an AIE effect in the presence of positively charged protamine, presenting a fluorescence enhancement at 498 nm together with a large Stokes shift of 150 nm and a low detection limit of 8.0 ng mL-1. In addition, the in situ formed TPE-2Py-SO3Na/protamine nanocomposite can be dissociated by trypsin due to the highly selective degradation of protamine via enzymatic hydrolysis, achieving a detection limit for trypsin as low as 5.0 ng mL-1.


Assuntos
Corantes Fluorescentes , Protaminas , Tripsina , Corantes Fluorescentes/química , Espectrometria de Fluorescência
3.
Polymers (Basel) ; 15(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37112003

RESUMO

Supercapacitors are widely used in various fields due to their high power density, fast charging and discharging speeds, and long service life. However, with the increasing demand for flexible electronics, integrated supercapacitors in devices are also facing more challenges, such as extensibility, bending stability, and operability. Despite many reports on stretchable supercapacitors, challenges still exist in their preparation process, which involves multiple steps. Therefore, we prepared stretchable conducting polymer electrodes by depositing thiophene and 3-methylthiophene on patterned 304 stainless steel (SS 304) through electropolymerization. The cycling stability of the prepared stretchable electrodes could be further improved by protecting them with poly(vinyl alcohol)/sulfuric acid (PVA/H2SO4) gel electrolyte. Specifically, the mechanical stability of the polythiophene (PTh) electrode was improved by 2.5%, and the stability of the poly(3-methylthiophene (P3MeT) electrode was improved by 7.0%. As a result, the assembled flexible supercapacitors maintained 93% of their stability even after 10,000 cycles of strain at 100%, which indicates potential applications in flexible electronics.

4.
Sensors (Basel) ; 22(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36502260

RESUMO

The localization of sensors in wireless sensor networks has recently gained considerable attention. The existing location methods are based on a one-spot measurement model. It is difficult to further improve the positioning accuracy of existing location methods based on single-spot measurements. This paper proposes two location methods based on multi-spot measurements to reduce location errors. Because the multi-spot measurements model has more measurement equations than the single-spot measurements model, the proposed methods provide better performance than the traditional location methods using one-spot measurement in terms of the root mean square error (RMSE) and Cramer-Rao lower bound (CRLB). Both closed-form and iterative algorithms are proposed in this paper. The former performs suboptimally with less computational burden, whereas the latter has the highest positioning accuracy in attaining the CRLB. Moreover, a novel CRLB for the proposed multi-spot measurements model is also derived in this paper. A theoretical proof shows that the traditional CRLB in the case of single-spot measurements performs worse than the proposed CRLB in the case of multi-spot measurements. The simulation results show that the proposed methods have a lower RMSE than the traditional location methods.


Assuntos
Algoritmos , Simulação por Computador
5.
Environ Pollut ; 301: 118960, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35150797

RESUMO

Perfluorooctane sulfonate (PFOS) is associated with male reproductive disorder, but the related mechanisms are still unclear. In this study, we used in vivo and in vitro models to explore the role of Sertoli cell-derived exosomes (SC-Exo)/miR-9-3p/StAR signaling pathway on PFOS-induced suppression of testosterone biosynthesis. Forty male ICR mice were orally administrated PFOS (0.5-10 mg/kg/bw) for 4 weeks. Bodyweight, organ index, sperm count, reproductive hormones were evaluated. Primary Sertoli cells and Leydig cells were used to delineate the molecular mechanisms that mediate the effects of PFOS on testosterone biosynthesis. Our results demonstrated that PFOS dose-dependently induced a decrease in sperm count, low levels of testosterone, and damage in testicular interstitium morphology. In vitro models, PFOS significantly increased miR-9-3p levels in Sertoli cells and SC-Exo, accompanied by a decrease in testosterone secretion and StAR expression in Leydig cells when Leydig cells were exposed to SC-Exo. Meanwhile, inhibition of SC-Exo or miR-9-3p by their inhibitors significantly rescued PFOS-induced decreases in testosterone secretion and the mRNA and protein expression of the StAR gene in Leydig cells. In summary, the present study highlights the role of the SC-Exo/miR-9-3p/StAR signaling pathway in PFOS-induced suppression of testosterone biosynthesis, advancing our understanding of molecular mechanisms for PFOS-induced male reproductive disorders.


Assuntos
Células Intersticiais do Testículo , MicroRNAs , Ácidos Alcanossulfônicos , Animais , Fluorocarbonos , Masculino , Camundongos , Camundongos Endogâmicos ICR , MicroRNAs/genética , MicroRNAs/metabolismo , Células de Sertoli , Testosterona/metabolismo
6.
Chem Commun (Camb) ; 58(15): 2520-2523, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35098291

RESUMO

A novel pyrene-pyridyl conjugated oligomer (OPP-OMe) was conveniently prepared by one-pot Sonogashira coupling. Intriguingly, it was found that introducing only one methoxy moiety at the 4-pyridyl position can be sufficient for creating an oligomer-based ultrafine reactive fluorescent nanoprobe, i.e., OPP-OMe NPs (ca. 2.5 nm in diameter). Spectral analyses and elucidation of the intermediate structure revealed that the methoxy triggered-oxidation, together with nanoaggregation of OPP-OMe NPs, results in rapid, specific and supersensitive sensing of hypochlorite (LOD, 0.3 nM, S/N = 3).

7.
Bioact Mater ; 6(12): 4455-4469, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34027234

RESUMO

Osteoarthritis (OA), characterized by chondrocyte apoptosis and disturbance of the balance between catabolism and anabolism of the extracellular matrix (ECM), is the most common age-related degenerative joint disease worldwide. As sleep has been found to be beneficial for cartilage repair, and circular RNAs (circRNAs) have been demonstrated to be involved in the pathogenesis of OA, we performed RNA sequencing (RNA-seq), and found circRNA3503 was significantly increased after melatonin (MT)-induced cell sleep. Upregulation of circRNA3503 expression completely rescued the effects of interleukin-1ß (IL-1ß), which was used to simulate OA, on apoptosis, ECM degradation- and synthesis-related genes. Mechanistically, circRNA3503 acted as a sponge of hsa-miR-181c-3p and hsa-let-7b-3p. Moreover, as we previously showed that small extracellular vesicles (sEVs) derived from synovium mesenchymal stem cells (SMSCs) can not only successfully deliver nucleic acids to chondrocytes, but also effectively promote chondrocyte proliferation and migration, we assessed the feasibility of sEVs in combination with sleep-related circRNA3503 as an OA therapy. We successfully produced and isolated circRNA3503-loaded sEVs (circRNA3503-OE-sEVs) from SMSCs. Then, poly(D,l-lactide)-b-poly(ethylene glycol)-b-poly(D,l-lactide) (PDLLA-PEG-PDLLA, PLEL) triblock copolymer gels were used as carriers of sEVs. Through in vivo and in vitro experiments, PLEL@circRNA3503-OE-sEVs were shown to be a highly-effective therapeutic strategy to prevent OA progression. Through multiple pathways, circRNA3503-OE-sEVs alleviated inflammation-induced apoptosis and the imbalance between ECM synthesis and ECM degradation by acting as a sponge of hsa-miR-181c-3p and hsa-let-7b-3p. In addition, circRNA3503-OE-sEVs promoted chondrocyte renewal to alleviate the progressive loss of chondrocytes. Our results highlight the potential of PLEL@circRNA3503-OE-sEVs for preventing OA progression.

8.
iScience ; 24(3): 102200, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33733065

RESUMO

Functional healing of tendon injuries remains a great challenge. Small extracellular vesicles (sEVs) have received attention as pro-regenerative agents. H19 overexpression could bring tendon regenerative ability, but the mechanism is still not fully elucidated, and reliable method for delivery of long non-coding RNAs (LncRNAs) was demanded. We identified the downstream mechanism of H19, the activation of yes-associated protein (YAP) via the H19-PP1-YAP axis. We established tendon stem/progenitor cells (TSPCs) stably overexpressing H19 with CRISPR-dCas9-based hnRNP A2/B1 activation (H19-CP-TSPCs). H19-OL-sEVs (H19 "overloading" sEVs) could be produced effectively from H19-CP-TSPCs. Only H19-OL-sEVs were able to significantly load large amounts of H19 rather than other competitors, and the potential of H19-OL-sEVs to promote tendon healing was far better than that of other competitors. Our study established a relatively reliable method for enrichment of LncRNAs into sEVs, providing new hints for modularized sEV-based therapies, and modularized sEVs represented a potential strategy for tendon regeneration.

9.
Toxicology ; 449: 152663, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33359577

RESUMO

Perfluorooctane sulfonate (PFOS), a stable end-product of perfluorinated compounds (PFCs), is associated with male reproductive disorders, but its underlying mechanisms are still unclear. We used in vivo and in vitro models to investigate the effects of PFOS on testosterone biosynthesis and related mechanisms. First, male ICR mice were orally administered PFOS (0-10 mg/kg/bw) for 4 weeks. Bodyweight, sperm count, reproductive hormones, mRNA expression of the genes related to testosterone biosynthesis, and the protein expression of protein kinase A (PKA), p38 mitogen-activated protein kinase (MAPK), cAMP-response element binding protein (CREB), CREB regulated transcription coactivator 2 (CRTC2) and steroidogenic acute regulatory protein (StAR) were evaluated. Furthermore, mouse primary Leydig cells were used to delineate the molecular mechanisms that mediate the effects of PFOS on testosterone biosynthesis. Our results demonstrated that PFOS dose-dependently decreased sperm count, testosterone level, CRTC2/StAR expression, and damaged testicular interstitium morphology, paralleled by increase in phosphorylated PKA, CREB and p38 in testes. Additionally, similar to the in vivo results, PFOS significantly decreased testosterone secretion, CRTC2/StAR expression, interaction between CREB and CRTC2 and binding of CREB/CRTC2 to StAR promoter region, paralleled by increase in phosphorylated-p38, PKA, and CREB expression. Meanwhile, inhibition of p38 by SB203580, or inhibition of PKA by H89 can significantly alleviate the above PFOS-induced effects. As such, the present study highlights a role of the CREB/CRTC2/StAR signaling pathway in PFOS-induced suppression of testosterone biosynthesis, advancing our understanding of molecular mechanisms for PFOS-induced male reproductive disorders.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Fluorocarbonos/toxicidade , Células Intersticiais do Testículo/metabolismo , Fosfoproteínas/metabolismo , Testosterona/biossíntese , Fatores de Transcrição/metabolismo , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Relação Dose-Resposta a Droga , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosfoproteínas/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Testosterona/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores
10.
Adv Biosyst ; 4(9): e2000152, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32803878

RESUMO

The prognosis for osteosarcoma (OS) continues to be unsatisfactory due to tumor recurrence as a result of metastasis and drug resistance. Several studies have shown that Ewing sarcoma associated transcript 1 (EWSAT1) plays an important role in the progression of OS. Exosomes (Exos) act as important carriers in intercellular communication and play an important role in the tumor microenvironment, especially in tumor-induced angiogenesis. Nonetheless, the specific mechanism via which EWSAT1 and Exos regulate OS progression is unknown, and whether they can be effective therapeutic targets also requires verification. Hence, in this study, it is aimed to investigate the mechanisms of action of EWSAT1 and Exos. EWSAT1 significantly promotes proliferation, migration, colony formation, and survival of OS. EWSAT1 regulates OS-induced angiogenesis via two mechanisms, called the "double stacking effect," which is a combination of the increase in sensitivity/reactivity of vascular endothelial cells triggered by Exos-carrying EWSAT1, and the EWSAT1-induced increase in angiogenic factor secretion. In vivo experiments further validates the "double stacking effect" and shows that EWSAT1-KD effectively inhibits tumor growth in OS. The above observations indicate that EWSAT1 can be used as not only a potential diagnostic and prognostic marker, but also as a precise therapeutic target for OS.


Assuntos
Exossomos/metabolismo , Neovascularização Patológica/metabolismo , Osteossarcoma , RNA Longo não Codificante , Animais , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Osteossarcoma/genética , Osteossarcoma/metabolismo , Osteossarcoma/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
11.
Sensors (Basel) ; 17(12)2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29244727

RESUMO

Localization of a moving target in a dual-frequency radars system has now gained considerable attention. The noncoherent localization approach based on a least squares (LS) estimator has been addressed in the literature. Compared with the LS method, a novel localization method based on a two-step weighted least squares estimator is proposed to increase positioning accuracy for a multi-station dual-frequency radars system in this paper. The effects of signal noise ratio and the number of samples on the performance of range estimation are also analyzed in the paper. Furthermore, both the theoretical variance and Cramer-Rao lower bound (CRLB) are derived. The simulation results verified the proposed method.

12.
Sensors (Basel) ; 16(9)2016 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-27618055

RESUMO

The localization of a sensor in wireless sensor networks (WSNs) has now gained considerable attention. Since the transmit power and path loss exponent (PLE) are two critical parameters in the received signal strength (RSS) localization technique, many RSS-based location methods, considering the case that both the transmit power and PLE are unknown, have been proposed in the literature. However, these methods require a search process, and cannot give a closed-form solution to sensor localization. In this paper, a novel RSS localization method with a closed-form solution based on a two-step weighted least squares estimator is proposed for the case with the unknown transmit power and uncertainty in PLE. Furthermore, the complete performance analysis of the proposed method is given in the paper. Both the theoretical variance and Cramer-Rao lower bound (CRLB) are derived. The relationships between the deterministic CRLB and the proposed stochastic CRLB are presented. The paper also proves that the proposed method can reach the stochastic CRLB.

13.
Shanghai Kou Qiang Yi Xue ; 25(3): 340-4, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-27609390

RESUMO

PURPOSE: To evaluate the feasibility and clinical outcomes of an atraumatic extraction technique using Benex Extraction System in flapless immediate implant placement in anterior teeth. METHODS: Twenty-five patients with single hopeless anterior maxillary teeth were enrolled in the study. The involved teeth were extracted using Benex Extraction System and implants were immediately placed in a flapless way. Healing abutments were connected immediately. After 4-6 months of healing, screw-retained implant temporary crowns were used to reshape the peri-implant gingiva. Permanent restorations were delivered 3 months later. Extraction time was recorded and the technique feasibility was evaluated using visual analogue scale (VAS). Peri-implant marginal bone resorption was measured in X- ray films after loading for 1 year later. Pink esthetic score (PES) was checked to evaluate the gingival esthetics. Questionnaire was delivered and collected to assess patients' satisfaction on surgical experience and esthetic outcomes. SPSS 13.0 software package was used for statistical analysis. RESULTS: Twenty-five implants osseointegrated successfully. The marginal bone resorption was (0.21±0.23) mm and PES was 8.8±1.19 after loading for 1 year. The mean extraction time was 6.87 minutes and the VAS was 3.32. All patients were satisfied with the final esthetic outcomes and felt comfort during surgery. CONCLUSIONS: According to the limited data in the study, Benex extraction System is a convenient, atraumatic and predictable technique during flapless immediate implant placement in anterior teeth.


Assuntos
Dieta/estatística & dados numéricos , Líquen Plano Bucal/epidemiologia , Adesão à Medicação/estatística & dados numéricos , Adulto , Coroas , Implantes Dentários para Um Único Dente , Estética , Estética Dentária , Feminino , Seguimentos , Gengiva , Humanos , Carga Imediata em Implante Dentário , Masculino , Pessoa de Meia-Idade , Osseointegração , Satisfação do Paciente , Alvéolo Dental , Resultado do Tratamento
14.
Shanghai Kou Qiang Yi Xue ; 23(3): 304-7, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25102872

RESUMO

PURPOSE: Human telomerase reverse transcriptase (hTRT) was transfected into cultured oral keratinocytes (OKC) mediated by pBABE-tert recombined retrovirus to investigate the effect on OKC lifespan. METHODS: pBABE-tert recombined retrovirus loaded with hTRT gene was amplified by transfected PT67 cells, and then transfected into cultured OKC in vitro. The positive clones of OKC were separated by puromycin and subcultured. Telomerase activity was analyzed by telomerase PCR-ELISA and PCR-PAGE. RESULTS: The hTRT positive clones of OKC showed telomerase expression, with extending lifespan to 8-9 passages. CONCLUSIONS: The hTRT transfected OKC can prolong doubly lifespan but not be immortalized, which indicates that cellular immortality mechanism is complicated and multi-controled. Telomerase activity is the key for cell immortalization but not the only impact factor.


Assuntos
Queratinócitos , Retroviridae , Transfecção , Linhagem Celular , Proteínas de Ligação a DNA , Humanos , Telomerase
15.
ScientificWorldJournal ; 2014: 274897, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25089286

RESUMO

Channel estimation problem is one of the key technical issues in sparse frequency-selective fading multiple-input multiple-output (MIMO) communication systems using orthogonal frequency division multiplexing (OFDM) scheme. To estimate sparse MIMO channels, sparse invariable step-size normalized least mean square (ISS-NLMS) algorithms were applied to adaptive sparse channel estimation (ACSE). It is well known that step-size is a critical parameter which controls three aspects: algorithm stability, estimation performance, and computational cost. However, traditional methods are vulnerable to cause estimation performance loss because ISS cannot balance the three aspects simultaneously. In this paper, we propose two stable sparse variable step-size NLMS (VSS-NLMS) algorithms to improve the accuracy of MIMO channel estimators. First, ASCE is formulated in MIMO-OFDM systems. Second, different sparse penalties are introduced to VSS-NLMS algorithm for ASCE. In addition, difference between sparse ISS-NLMS algorithms and sparse VSS-NLMS ones is explained and their lower bounds are also derived. At last, to verify the effectiveness of the proposed algorithms for ASCE, several selected simulation results are shown to prove that the proposed sparse VSS-NLMS algorithms can achieve better estimation performance than the conventional methods via mean square error (MSE) and bit error rate (BER) metrics.


Assuntos
Algoritmos , Análise dos Mínimos Quadrados , Tecnologia sem Fio
16.
Shanghai Kou Qiang Yi Xue ; 23(2): 188-91, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-24935841

RESUMO

PURPOSE: To construct a database and a tissue bank of oral mucosa precancerous lesions and to estimate the application values. METHODS: Patients in the Yangtze delta suffering oral mucosa precancerous lesions were enrolled into this study. The patients' clinical data and samples of oral precancerous mucosa, salivary and blood were collected to create a tissue bank, based on which a database was constructed using Microsoft Access software, Brower/Server structure and ASP language. RESULTS: The tissue bank and database of oral mucosa precancerous lesions were successfully built. The procedure to harvest, store and transport the samples had been standardized. The database showed good interactive interface, convenient for data collection, query and share in the internet. CONCLUSIONS: We constructed the tissue bank and database of oral mucosa precancerous lesions for the first time, which not only help preserve the biological resource of oral mucosa precancerous lesions, but also provide enormous convenience in clinical work, researching and teaching. Supported by Research Fund of Science and Technology Committee of Shanghai Municipality (08ZR1416700).


Assuntos
Mucosa Bucal , Neoplasias Bucais , China , Bases de Dados Factuais , Humanos , Bancos de Tecidos
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