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1.
Chem Commun (Camb) ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38836703

RESUMO

Cobalt substitution for manganese sites in Na0.44MnO2 initiates a dynamic structural evolution process, yielding a composite cathode material comprising intergrown P2 and P3 phases. The novel P2/P3 composite cathode exhibits a reversible phase transition process during Na+ extraction/insertion, showcasing its attractive battery performance in sodium-ion batteries.

2.
ACS Nano ; 18(20): 12945-12956, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717846

RESUMO

P3-layered transition oxide cathodes have garnered considerable attention owing to their high initial capacity, rapid Na+ kinetics, and less energy consumption during the synthesis process. Despite these merits, their practical application is hindered by the substantial capacity degradation resulting from unfavorable structural transformations, Mn dissolution and migration. In this study, we systematically investigated the failure mechanisms of P3 cathodes, encompassing Mn dissolution, migration, and the irreversible P3-O3' phase transition, culminating in severe structural collapse. To address these challenges, we proposed an interfacial spinel local interlocking strategy utilizing P3/spinel intergrowth oxide as a proof-of-concept material. As a result, P3/spinel intergrowth oxide cathodes demonstrated enhanced cycling performance. The effectiveness of suppressing Mn migration and maintaining local structure of interfacial spinel local interlocking strategy was validated through depth-etching X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and in situ synchrotron-based X-ray diffraction. This interfacial spinel local interlocking engineering strategy presents a promising avenue for the development of advanced cathode materials for sodium-ion batteries.

3.
Chem Sci ; 15(14): 5192-5200, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38577355

RESUMO

Layered transition metal oxides (NaxTMO2) possess attractive features such as large specific capacity, high ionic conductivity, and a scalable synthesis process, making them a promising cathode candidate for sodium-ion batteries (SIBs). However, NaxTMO2 suffer from multiple phase transitions and Na+/vacancy ordering upon Na+ insertion/extraction, which is detrimental to their electrochemical performance. Herein, we developed a novel cathode material that exhibits an abnormal P2-type structure at a stoichiometric content of Na up to 1. The cathode material delivers a reversible capacity of 108 mA h g-1 at 0.2C and 97 mA h g-1 at 2C, retaining a capacity retention of 76.15% after 200 cycles within 2.0-4.3 V. In situ diffraction studies demonstrated that this material exhibits an absolute solid-solution reaction with a low volume change of 0.8% during cycling. This near-zero-strain characteristic enables a highly stabilized crystal structure for Na+ storage, contributing to a significant improvement in battery performance. Overall, this work presents a simple yet effective approach to realizing high Na content in P2-type layered oxides, offering new opportunities for high-performance SIB cathode materials.

4.
Sensors (Basel) ; 24(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38400292

RESUMO

In recent years, advancements in deep Convolutional Neural Networks (CNNs) have brought about a paradigm shift in the realm of image super-resolution (SR). While augmenting the depth and breadth of CNNs can indeed enhance network performance, it often comes at the expense of heightened computational demands and greater memory usage, which can restrict practical deployment. To mitigate this challenge, we have incorporated a technique called factorized convolution and introduced the efficient Cross-Scale Interaction Block (CSIB). CSIB employs a dual-branch structure, with one branch extracting local features and the other capturing global features. Interaction operations take place in the middle of this dual-branch structure, facilitating the integration of cross-scale contextual information. To further refine the aggregated contextual information, we designed an Efficient Large Kernel Attention (ELKA) using large convolutional kernels and a gating mechanism. By stacking CSIBs, we have created a lightweight cross-scale interaction network for image super-resolution named "CSINet". This innovative approach significantly reduces computational costs while maintaining performance, providing an efficient solution for practical applications. The experimental results convincingly demonstrate that our CSINet surpasses the majority of the state-of-the-art lightweight super-resolution techniques used on widely recognized benchmark datasets. Moreover, our smaller model, CSINet-S, shows an excellent performance record on lightweight super-resolution benchmarks with extremely low parameters and Multi-Adds (e.g., 33.82 dB@Set14 × 2 with only 248 K parameters).

5.
ACS Appl Mater Interfaces ; 16(2): 2330-2340, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38165730

RESUMO

It remains a tremendous challenge to achieve high-efficiency bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) for hydrogen production by water splitting. Herein, a novel hybrid of 0D nickel nanoparticles dispersed on the one-dimensional (1D) molybdenum carbide micropillars embedded in the carbon layers (Ni/Mo2C@C) was successfully prepared on nickel foam by a facile pyrolysis strategy. During the synthesis process, the nickel nanoparticles and molybdenum carbide were simultaneously generated under H2 and C2H2 mixed atmospheres and conformally encapsulated in the carbon layers. Benefiting from the distinctive 0D/1D heterostructure and the synergistic effect of the biphasic Mo2C and Ni together with the protective effect of the carbon layer, the reduced activation energy barriers and fast catalytic reaction kinetics can be achieved, resulting in a small overpotential of 96 mV for the HER and 266 mV for the OER at the current density of 10 mA cm-2 together with excellent durability in 1.0 M KOH electrolyte. In addition, using the developed Ni/Mo2C@C as both the cathode and anode, the constructed electrolyzer exhibits a small voltage of 1.55 V for the overall water splitting. The novel designed Ni/Mo2C@C may give inspiration for the development of efficient bifunctional catalysts with low-cost transition metal elements for water splitting.

6.
Adv Mater ; 36(15): e2307938, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37910130

RESUMO

Layered oxides have become the research focus of cathode materials for sodium-ion batteries (SIBs) due to the low cost, simple synthesis process, and high specific capacity. However, the poor air stability, unstable phase structure under high voltage, and slow anionic redox kinetics hinder their commercial application. In recent years, the concept of manipulating orbital hybridization has been proposed to simultaneously regulate the microelectronic structure and modify the surface chemistry environment intrinsically. In this review, the hybridization modes between atoms in 3d/4d transition metal (TM) orbitals and O 2p orbitals near the region of the Fermi energy level (EF) are summarized based on orbital hybridization theory and first-principles calculations as well as various sophisticated characterizations. Furthermore, the underlying mechanisms are explored from macro-scale to micro-scale, including enhancing air stability, modulating high working voltage, and stabilizing anionic redox chemistry. Meanwhile, the origin, formation conditions, and different types of orbital hybridization, as well as its application in layered oxide cathodes are presented, which provide insights into the design and preparation of cathode materials. Ultimately, the main challenges in the development of orbital hybridization and its potential for the production application are also discussed, pointing out the route for high-performance practical sodium layered oxide cathodes.

7.
Epigenomics ; 14(20): 1233-1247, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36444681

RESUMO

Aim: We aimed to identify potent CpG signatures predicting temozolomide (TMZ) response in glioblastomas (GBMs) that do not have the glioma-CpG island methylator phenotype (G-CIMP) but have a methylated promoter of MGMT (meMGMT). Materials & methods: Different datasets of non-G-CIMP meMGMT GBMs with molecular and clinical data were analyzed. Results: A panel of 77 TMZ efficacy-related CpGs and a seven-CpG risk signature were identified and validated for distinguishing differential outcomes to radiotherapy plus TMZ versus radiotherapy alone in non-G-CIMP meMGMT GBMs. An integrated classification scheme was also proposed for refining a MGMT-based TMZ-guiding approach in all G-CIMP-GBMs. Conclusion: The CpG signatures may serve as promising predictive biomarker candidates for guiding optimal TMZ usage in non-G-CIMP meMGMT GBMs.


Glioblastomas that do not have the glioma-CpG island methylator phenotype (G-CIMP) but have a methylated promoter of the MGMT gene (meMGMT) show considerable variability in their response to temozolomide (TMZ). Powerful biomarkers that provide predictive information on optimal TMZ decision-making can be clinically useful. This study has identified and validated a panel of 77 TMZ efficacy-related CpGs and a seven-CpG risk signature for predicting TMZ usage in non-G-CIMP meMGMT glioblastomas. An integrated classification scheme is proposed for refining a MGMT-based TMZ-guiding approach in non-G-CIMP glioblastomas.


Assuntos
Glioblastoma , Glioma , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Ilhas de CpG , Glioma/tratamento farmacológico , Glioma/genética , Fenótipo , Metilases de Modificação do DNA/genética , Proteínas Supressoras de Tumor/genética , Enzimas Reparadoras do DNA/genética
8.
Huan Jing Ke Xue ; 43(10): 4706-4715, 2022 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-36224156

RESUMO

Rice straw is an important organic fertilizer in the region for double-cropping rice in South China. To reveal the effects of early rice returning with reducing potassium fertilizer on the yield of late rice and soil fertility, field experiments were carried out in Baiyun and Huiyang district in Guangdong province. The biomass, K content, and yield of late rice and the soil fertility properties, such as soil available potassium, soil organic carbon, bacterial diversity, and bacterial community structure were analyzed under three treatments (CK, conventional fertilization; RS, straw returning with conventional fertilization; RS-K, straw returning with reducing 20% potassium fertilizer). The results showed no significant differences in the biomass and yield of late rice between the RS-K treatment and CK treatment. Compared with that in CK, the RS treatment significantly increased the K contents of rice by 3.97% (Baiyun) and 6.91% (Huiyang). The K contents of late rice under the RS-K treatment were significantly lower than that under the CK treatment during the early growth period in rice, but there was no significant difference between them during the late growth period. Compared with that in CK, the soil available K in the RS treatment increased by 13.90% (Baiyun) and 21.67% (Huiyang) (P<0.05), and the soil available K in the RS-K treatment also increased by 3.56% (Baiyun) and 4.23% (Huiyang). Compared with that in the CK treatment, the soil dissolved organic carbon increased significantly in the RS and RS-K treatments (P<0.05). Compared with that in CK, the straw returning treatments (RS and RS-K) significantly improved the Chao1 and Shannon indexes of soil bacteria (P<0.05). Straw returning treatments (RS and RS-K) increased the relative abundance of Proteobacteria, Actinobacteria, and Nitrospirae compared with that in CK, whereas they decreased the relative abundance of Acidobacteria, Bacteroidetes, and Firmicutes. Redundancy analysis showed that the soil bacterial community was mainly influenced by soil organic carbon, dissolved organic carbon, microbial biomass carbon, available P, and available K. In summary, early rice returning could increase soil available K and K content in late rice. Early rice straw returning with reducing potassium fertilizer had no negative impacts on the growth and yield of late rice and could also improve soil organic carbon and the diversity of soil bacteria. Therefore, early rice straw returning with reducing potassium fertilizer can guarantee the grain yield of late rice and improve soil fertility.


Assuntos
Fertilizantes , Oryza , Agricultura/métodos , Bactérias , Carbono , Potássio/química , Solo/química
9.
Zootaxa ; 5141(6): 592-600, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36095771

RESUMO

Three new species of the genus Hexarhopalus Fairmaire, 1891, all of the nominate subgenus, are described and figured from China: Hexarhopalus (Hexarhopalus) ferreri sp. nov. from Yunnan, H. (H.) tianbaoyanensis sp. nov. from Fujian, and H. (H.) yeziyangi sp. nov. from Jiangxi.


Assuntos
Besouros , Distribuição Animal , Animais , China
10.
Eur J Nutr ; 61(4): 1823-1836, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34997266

RESUMO

PURPOSE: Diabetic cardiomyopathy (DCM), a common complication of diabetes mellitus and is characterized by myocardial hypertrophy and myocardial fibrosis. Pyrroloquinoline quinone (PQQ), a natural nutrient, exerts strong protection against various myocardial diseases. Pyroptosis, a type of inflammation-related programmed cell death, is vital to the development of DCM. However, the protective effects of PQQ against DCM and the associated mechanisms are not clear. This study aimed to investigate whether PQQ protected against DCM and to determine the underlying molecular mechanism. METHODS: Diabetes was induced in mice by intraperitoneal injection of streptozotocin, after which the mice were administered PQQ orally (10, 20, or 40 mg/kg body weight/day) for 12 weeks. AC16 human myocardial cells were divided into the following groups and treated accordingly: control (5.5 mmol/L glucose), high glucose (35 mmol/L glucose), and HG + PQQ groups (1 and 10 nmol/L PQQ). Cells were treated for 24 h. RESULTS: PQQ reduced myocardial hypertrophy and the area of myocardial fibrosis, which was accompanied by an increase in antioxidant function and a decrease in inflammatory cytokine levels. Moreover, myocardial hypertrophy-(ANP and BNP), myocardial fibrosis-(collagen I and TGF-ß1), and pyroptosis-related protein levels decreased in the PQQ treatment groups. Furthermore, PQQ abolished mitochondrial dysfunction and the activation of NF-κB/IκB, and decreased NLRP3 inflammation-mediated pyroptosis in AC16 cells under high-glucose conditions. CONCLUSION: PQQ improved DCM in diabetic mice by inhibiting NF-κB/NLRP3 inflammasome-mediated cell pyroptosis. Long-term dietary supplementation with PQQ may be greatly beneficial for the treatment of DCM. Diagram of the underlying mechanism of the effects of PQQ on DCM. PQQ inhibits ROS generation and NF-κB activation, which stimulates activation of the NLRP3 inflammasome and regulates the expression of caspase-1, IL-1ß, and IL-18. The up-regulated inflammatory cytokines trigger myocardial hypertrophy and cardiac fibrosis and promote the pathological process of DCM.


Assuntos
Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Animais , Cardiomegalia , Diabetes Mellitus Experimental/complicações , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/metabolismo , Fibrose , Glucose , Inflamassomos/metabolismo , Inflamação/complicações , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Cofator PQQ/metabolismo , Cofator PQQ/farmacologia , Cofator PQQ/uso terapêutico , Piroptose , Transdução de Sinais
11.
Mol Med Rep ; 24(4)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34396445

RESUMO

Osteoporosis is a severe bone disease commonly occurring in older males and postmenopausal females. Previous studies have shown that long non­coding (lnc)RNA growth arrest­specific 5 (GAS5) serves an important role in osteoporosis. However, its role is unclear and requires further exploration. The relative expression levels of GAS5 and miR­10a­3p in the serum samples of patients with osteoporosis, as well as the relative expression levels of GAS5, microRNA (miR)­10a­3p and vascular endothelial growth factor A (VEGFA) mRNA in osteoblasts, were detected by reverse transcription­quantitative PCR. ELISA and western blotting were used to detect the expression levels of VEGFA. A Matrigel angiogenesis test was used to assess the effects on angiogenesis. RNA binding interactions between GAS5/miR­10a­3p and miR­10a­3p/VEGFA were evaluated using dual­luciferase reporter assays. Furthermore, the effects of the GAS5/miR­10a­3p/VEGFA axis were investigated via ELISA, western blotting and Matrigel angiogenesis. GAS5 was significantly downregulated and miR­10a­3p was upregulated in patients with osteoporosis. Overexpression of GAS5 promoted angiogenesis. GAS5 acted as a sponge of miR­10a­3p; VEGFA was a target gene of miR­10a­3p. GAS5 induced angiogenesis by inhibiting miR­10a­3p and enhancing VEGFA expression. These results indicated that GAS5 overexpression increased angiogenesis by inhibiting miR­10a­3p, promoting the expression of VEGFA. The present study revealed a novel mechanism and provided novel targets for the clinical treatment of osteoporosis.


Assuntos
Indutores da Angiogênese/farmacologia , MicroRNAs/metabolismo , Neovascularização Patológica/tratamento farmacológico , Osteoporose/tratamento farmacológico , RNA Longo não Codificante/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Idoso , Regulação para Baixo , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Osteoblastos , Osteoporose/genética , RNA Longo não Codificante/genética , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/genética
12.
Reprod Sci ; 28(3): 785-793, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33211273

RESUMO

BNC1 is a transcription factor that is crucial for spermatogenesis and male fertility, although the underlying mechanism remains unclear. To study BNC1's specific role in spermatogenesis, we characterized a previously developed mouse model carrying a truncating mutation in Bnc1 (termed Bnc1+/tr for heterozygotes and Bnc1tr/tr for homozygotes) and found that the mutation decreased BNC1 protein levels and resulted in germ cell loss by apoptosis. Given that loss of functional Bnc1 is known to result in decreased expression of the spermatogenesis genes Ybx2 and Papolb, we aimed to explore whether and how BNC1 promotes transcription of Ybx2 and Papolb to mediate its role in spermatogenesis. We confirmed significant reduction in YBX2 and PAPOLB protein levels in testis tissue from Bnc1+/tr and Bnc1tr/tr males compared with wild-type mice (Bnc1+/+). Consistently, knockdown of Bnc1 led to downregulation of Ybx2 and Papolb in CRL-2196 cells in vitro. To investigate if BNC1 directly induces Ybx2 and Papolb gene expression, chromatin immunoprecipitation using mouse testicular tissue and luciferase reporter assays in HEK293 cells were used to identify functional binding of BNC1 to the Ybx2 and Papolb promoters at defined BNC1 binding sites. Taken together, this study reveals a mechanism for BNC1's role in spermatogenesis by directly binding to BNC1 binding elements in the promoter regions of both Ybx2 and Papolb and inducing transcription of these important spermatogenesis genes.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Polinucleotídeo Adenililtransferase/metabolismo , Regiões Promotoras Genéticas , Proteínas de Ligação a RNA/metabolismo , Espermatogênese , Espermatozoides/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Apoptose , Sítios de Ligação , Proliferação de Células , Proteínas de Ligação a DNA/genética , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Mutação , Polinucleotídeo Adenililtransferase/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética
13.
Zootaxa ; 4768(4): zootaxa.4768.4.4, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33055637

RESUMO

A taxonomic review of the genus Hechinoschema is presented. A new genus, Propedicellus gen. nov., is described, and two new species Propedicellus guoliangi sp. nov. and Propedicellus qiului sp. nov. are described from China. A new combination Propedicellus vitalisi (Pic, 1925) comb. nov. is proposed. A key to species of Propedicellus is presented.


Assuntos
Besouros , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , Tamanho do Órgão
14.
J Mol Cell Biol ; 12(1): 71-83, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31065688

RESUMO

Basonuclin (BNC1) is expressed primarily in proliferative keratinocytes and gametogenic cells. However, its roles in spermatogenesis and testicular aging were not clear. Previously we discovered a heterozygous BNC1 truncation mutation in a premature ovarian insufficiency pedigree. In this study, we found that male mice carrying the truncation mutation exhibited progressively fertility loss and testicular premature aging. Genome-wide expression profiling and direct binding studies (by chromatin immunoprecipitation sequencing) with BNC1 in mouse testis identified several spermatogenesis-specific gene promoters targeted by BNC1 including kelch-like family member 10 (Klhl10), testis expressed 14 (Tex14), and spermatogenesis and centriole associated 1 (Spatc1). Moreover, biochemical analysis showed that BNC1 was associated with TATA-box binding protein-associated factor 7 like (TAF7L), a germ cell-specific paralogue of the transcription factor IID subunit TAF7, both in vitro and in testis, suggesting that BNC1 might directly cooperate with TAF7L to regulate spermatogenesis. The truncation mutation disabled nuclear translocation of the BNC1/TAF7L complex, thus, disturbing expression of related genes and leading to testicular premature aging. Similarly, expressions of BNC1, TAF7L, Y-box-binding protein 2 (YBX2), outer dense fiber of sperm tails 1 (ODF1), and glyceraldehyde-3-phosphate dehydrogenase, spermatogenic (GAPDHS) were significantly decreased in the testis of men with non-obstructive azoospermia. The present study adds to the understanding of the physiology of male reproductive aging and the mechanism of spermatogenic failure in infertile men.


Assuntos
Senilidade Prematura/metabolismo , Azoospermia/metabolismo , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/metabolismo , Espermatogênese/genética , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Testículo/metabolismo , Fator de Transcrição TFIID/metabolismo , Fatores de Transcrição/deficiência , Fatores de Transcrição/metabolismo , Senilidade Prematura/genética , Animais , Azoospermia/genética , Azoospermia/patologia , Proteínas de Ligação a DNA/genética , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Transdução de Sinais/genética , Fatores Associados à Proteína de Ligação a TATA/genética , Fator de Transcrição TFIID/genética , Fatores de Transcrição/genética , Transfecção
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(2): 584-588, 2018 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29665936

RESUMO

OBJECTIVE: To investigate the differences of metabolic pathways of leucocyte-deplated RBCs prepared by using lipid whole blood and nomal blood during routine storage so as to provide some reference for clinical blood use. METHODS: Twenty U whole blood from 20 donors, including 10 U lipid blood and 10 U normal whole blood, were selected for preparing leukodepleted red blood cells, red blood cells were taken from storage bags on day 0, 14 and 35, respectively. Metabolites in the red blood cells were analyzed, red blood cell metabolic extracts were detected by UPLC-MS/MS. The metabolite data of RBC from 2 groups were analyzed by SIMCA-P 13.0 software using OPLS-DA and by SPSS 19.0 using Mann-Whitney U test. Difference of metabolic pathways was described according to different metabolites. RESULTS: The glucose, adenine, pyruvic acid, GSH, GSSG and niacinamide levels on day 0 in lipid RBCs were higher than those in the control group(P<0.05). The glucose, pyruvic acid and GSH levels on day 14 in lipid RBCs were lower than those in the control group (P<0.05), and the levels of adenine, GSSG and niacinamide were higher than that in the control group (P<0.05). The glucose level on day 0 was lower than that in the control group (P<0.05), and the levels of adenine and niacinamide were higher than those in the control group (P<0.05). but the pyruvic acid, GSH and GSSG levels were not significantly different between 2 groups (P>0.05). CONCLUSION: Compared with the normal red blood cells, the energy metabolism pathway decreases in lipid red blood cells within the storage period and pentose phosphate pathway increases.


Assuntos
Eritrócitos , Preservação de Sangue , Glucose , Humanos , Lipídeos , Espectrometria de Massas em Tandem
16.
Anal Bioanal Chem ; 409(23): 5491-5500, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28741110

RESUMO

Dephosphorylation of biomolecules under the catalysis of alkaline phosphatase (ALP) is a critical physiological process. Abnormal levels of ALP activity have been associated with a number of diseases; thus, a simple and sensitive assay of ALP activity is highly demanded. Herein, to simulate biological conditions, we labeled a hydrosoluble phosphorylated heptapeptide Gly-Pro-Gly-Asn-p-Tyr-Gly-Ala (pGA) with aminated heptamethine cyanine dye (Cy) to give a low fluorescent labeled peptide Cy-pGA. The synthesized Cy-pGA and Eu3+-doped oxide Y0.6Eu0.4VO4 nanoparticles (NPs) were employed respectively as acceptor and donor to in situ form a non-fluorescent Fluorescence Resonance Energy Transfer (FRET) Cy-pGA-NP system, with the help of the strong interaction between Eu3+ ions in the NPs and phosphate group in Cy-pGA. The breaking of the FRET system of Cy-pGA-NP was triggered by the removal of phosphate group in Cy-pGA catalyzed by ALP and resulting in the release of fluorescent Y0.6Eu0.4VO4 NPs. Thus, the formed Cy-pGA-NP as a sensitive sensor can very well respond to the activity of ALP by measuring the time-resolved fluorescent intensity at near-infrared 617 nm (λ ex = 320 nm, delay time 400 µs). This sensor can not only accurately measure the activity of ALP (1-5 mU/mL) in the designed solutions, but it can also be applied to detect the activity of ALP in biological samples, such as cell lysate and human serum, without the interference of autofluorescent background of biosamples and screen ALP inhibitor by a simple mix-and-measure manner. Graphical abstract A biosensor of alkaline phosphatase (ALP) based on non-fluorescent FRET of Eu3+-doped oxide Y0.6Eu0.4VO4 nanoparticles and the phosphorylated heptapeptide labeled with cyanine dye (Cy-pGA).


Assuntos
Fosfatase Alcalina/metabolismo , Técnicas Biossensoriais , Európio/química , Corantes Fluorescentes/química , Peptídeos/química , Transferência Ressonante de Energia de Fluorescência , Fosforilação
17.
Eur J Obstet Gynecol Reprod Biol ; 211: 140-145, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28259006

RESUMO

OBJECTIVE(S): Assisted reproductive technology (ART) is associated with DNA methylation dysfunction of offspring. However, it is unclear whether ovarian stimulation (OS) is responsible for DNA methylation dysfunction of offspring STUDY DESIGN: We built the first-generation (F1) and second-generation (F2) offspring mice model of ovarian stimulation. Bodyweight of F1 and F2 were measured. Expression levels of several imprinted genes (Impact, H19, Igf2, Plagl1, Mest, and Snrpn) in F1 placenta were tested. Methylation status of Plagl1 and H19 promoters was examined with bisulfite sequencing. Glucose tolerance, blood pressure, and heart rate were evaluated in F2 mice. RESULTS: The OS F1 showed elevated bodyweights in the 2nd, 3rd and 4th weeks, but the difference disappeared in the 5th week. Plagl1 was down-regulated in OS F1. Promoters of Plagl1 and H19 were also hypermethylated in OS F1. F2 of OS mice had the similar bodyweight and glucose tolerance compared with the control F2. However, F2 of OS ♂F1+OS♀ F1 showed the decreased systolic pressure, diastolic pressure, and heart rate. CONCLUSIONS: Ovarian stimulation perturbs expression levels and methylation status of imprinted genes in offspring. The effect of ovarian stimulation may be passed to F2.


Assuntos
Pressão Sanguínea/fisiologia , Peso Corporal/genética , Metilação de DNA , Impressão Genômica , Indução da Ovulação , Animais , Proteínas de Ciclo Celular/genética , Feminino , Genes Supressores de Tumor , Fator de Crescimento Insulin-Like II/genética , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Gravidez , Regiões Promotoras Genéticas , Proteínas/genética , RNA Longo não Codificante/genética , Fatores de Transcrição/genética , Proteínas Centrais de snRNP/genética
18.
Hum Genet ; 136(2): 227-239, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27896428

RESUMO

Mechanisms underlying female gonadal dysgenesis remain unclarified and relatively unstudied. Whether X-chromosome inactivation (XCI)-escaping genes and microRNAs (miRNAs) contribute to this condition is currently unknown. We compared 45,X Turner Syndrome women with 46,XX normal women, and investigated differentially expressed miRNAs in Turner Syndrome through plasma miRNA sequencing. We found that miR-320a was consistently upregulated not only in 45,X plasma and peripheral blood mononuclear cells (PBMCs), but also in 45,X fetal gonadal tissues. The levels of miR-320a in PBMCs from 45,X, 46,XX, 46,XY, and 47,XXY human subjects were inversely related to the expression levels of XCI-escaping gene KDM5C in PBMCs. In vitro models indicated that KDM5C suppressed miR-320a transcription by directly binding to the promoter of miR-320a to prevent histone methylation. In addition, we demonstrated that KITLG, an essential gene for ovarian development and primordial germ cell survival, was a direct target of miR-320a and that it was downregulated in 45,X fetal gonadal tissues. In conclusion, we demonstrated that downregulation of miR-320a by the XCI-escaping gene KDM5C contributed to ovarian development by targeting KITLG.


Assuntos
Histona Desmetilases/genética , MicroRNAs/genética , Ovário/crescimento & desenvolvimento , Síndrome de Turner/genética , Inativação do Cromossomo X/genética , Adolescente , Adulto , Sequência de Aminoácidos , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Regulação para Baixo , Feminino , Regulação da Expressão Gênica , Ontologia Genética , Células HEK293 , Humanos , Leucócitos Mononucleares/metabolismo , MicroRNAs/sangue , Regiões Promotoras Genéticas , Análise de Sequência de RNA , Regulação para Cima , Adulto Jovem
19.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 44(3): 237-46, 2015 05.
Artigo em Chinês | MEDLINE | ID: mdl-26350002

RESUMO

OBJECTIVE: To investigate the factors related to clinical pregnancy outcomes of in vitro fertilization-embryo transfer (IVF-ET) in women with secondary infertility. METHODS: The clinical, laboratory and follow-up data of 1129 cycles in 1099 patients with secondary infertility undergoing IVF-ET in Women's Hospital, Zhejiang University School of Medicine between July 2012 to July 2014 were retrospectively reviewed. The factors related to pregnancy outcomes were analyzed by univariate and logistic regression methods. The clinical pregnancy rates in women with different age and different number of embryos transferred were compared. The clinical outcomes of stimulation with gonadotropin releasing hormone (GnRH) agonist long protocol, GnRH agonist short protocol and GnH antagonist protocol were evaluated in secondary infertile patients aged ≥ 40 years. RESULTS: Among 1129 cycles, 376 cases (33.30%) had clinical pregnancy and 753 cases (66.70%) had no clinical pregnancy. There were significant differences in age, body mass index, basal follicle-stimulating hormone level, antral follicle number,paternal age and number of embryos transferred between pregnancy and no pregnancy groups (P<0.05); while only maternal age (OR=0.900, 95% CI: 0.873~0.928, P<0.001) and the number of embryos transferred (OR=2.248, 95% CI: 1.906~2.652, P<0.001) were the independent factors affecting the clinical pregnancy outcome of IVF-ET. There was no significant difference in clinical pregnancy rate between women aged 30~40 years with two embryos transferred and those aged<30 years with two or three embryos transferred(P>0.05). There were no significances in clinical pregnancy rate among women aged ≥ 40 years using GnRH agonist long protocol,GnRH agonist short protocol and GnRH antagonist protocol for stimulation (P>0.05). CONCLUSION: Maternal age and number of embryos transferred have independent effect on IVF-ET clinical pregnancy outcome of secondary infertile women. We suggest that no more than two embryos should be transferred for women in their thirties to minimize the risk of multiple pregnancy while still having an acceptable pregnancy rate. The pregnancy rate of patients over 40 years decreases significantly, and there is no difference in pregnancy rate by using GnRH agonist long protocol, GnRH agonist short protocol or GnRH antagonist protocol.


Assuntos
Transferência Embrionária , Fertilização in vitro , Resultado da Gravidez , Adulto , Feminino , Hormônio Foliculoestimulante , Hormônio Liberador de Gonadotropina/agonistas , Gonadotropinas , Antagonistas de Hormônios/uso terapêutico , Humanos , Infertilidade Feminina , Idade Materna , Folículo Ovariano , Indução da Ovulação , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
20.
J Zhejiang Univ Sci B ; 15(8): 750-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25091994

RESUMO

Ectopic pregnancy is identified with the widely-applied assisted reproductive technology (ART). Bilateral ectopic pregnancy is a rare form of ectopic pregnancy which is difficult to be diagnosed at the pre-operation stage. In this paper, we presented an unusual case of heterochronic bilateral ectopic pregnancy after stimulated intrauterine insemination (IUI), where there has been a delay of 22 d between the diagnoses of the two ectopic pregnancies. Literature was reviewed on the occurrence of bilateral ectopic pregnancy during the past four years in the MEDLINE database. We found 16 cases of bilateral ectopic pregnancy reported since 2008, and analyzed the characteristics of those cases of bilateral ectopic pregnancy. We emphasize that ovulation induction and other ARTs may increase the risk of bilateral ectopic pregnancy. Because of the difficulty in identification of bilateral ectopic pregnancy by ultrasonography, the clinician should be aware that the treatment of one ectopic pregnancy does not preclude the occurrence of a second ectopic pregnancy in the same patient and should pay attention to the intra-operation inspection of both side fallopian tubes in any ectopic pregnancy case.


Assuntos
Indução da Ovulação/efeitos adversos , Gravidez Ectópica/etiologia , Adulto , Gonadotropina Coriônica/sangue , Feminino , Humanos , Gravidez , Gravidez Ectópica/diagnóstico , Gravidez Ectópica/diagnóstico por imagem , Técnicas de Reprodução Assistida/efeitos adversos , Fatores de Risco , Fatores de Tempo , Ultrassonografia
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