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1.
BMC Genomics ; 25(1): 329, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566035

RESUMO

BACKGROUND: Previously, a novel multiplex system of 64 loci was constructed based on capillary electrophoresis platform, including 59 autosomal insertion/deletions (A-InDels), two Y-chromosome InDels, two mini short tandem repeats (miniSTRs), and an Amelogenin gene. The aim of this study is to evaluate the efficiencies of this multiplex system for individual identification, paternity testing and biogeographic ancestry inference in Chinese Hezhou Han (CHH) and Hubei Tujia (CTH) groups, providing valuable insights for forensic anthropology and population genetics research. RESULTS: The cumulative values of power of discrimination (CDP) and probability of exclusion (CPE) for the 59 A-InDels and two miniSTRs were 0.99999999999999999999999999754, 0.99999905; and 0.99999999999999999999999999998, 0.99999898 in CTH and CHH groups, respectively. When the likelihood ratio thresholds were set to 1 or 10, more than 95% of the full sibling pairs could be identified from unrelated individual pairs, and the false positive rates were less than 1.2% in both CTH and CHH groups. Biogeographic ancestry inference models based on 35 populations were constructed with three algorithms: random forest, adaptive boosting and extreme gradient boosting, and then 10-fold cross-validation analyses were applied to test these three models with the average accuracies of 86.59%, 84.22% and 87.80%, respectively. In addition, we also investigated the genetic relationships between the two studied groups with 33 reference populations using population statistical methods of FST, DA, phylogenetic tree, PCA, STRUCTURE and TreeMix analyses. The present results showed that compared to other continental populations, the CTH and CHH groups had closer genetic affinities to East Asian populations. CONCLUSIONS: This novel multiplex system has high CDP and CPE in CTH and CHH groups, which can be used as a powerful tool for individual identification and paternity testing. According to various genetic analysis methods, the genetic structures of CTH and CHH groups are relatively similar to the reference East Asian populations.


Assuntos
Genética Populacional , Irmãos , Humanos , Filogenia , China , Mutação INDEL , Repetições de Microssatélites , Genética Forense/métodos , Frequência do Gene
2.
Environ Res ; 231(Pt 3): 116249, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37247656

RESUMO

In this study, humic acid (HA) enhanced 17ß-estradiol (17ß-E2) degradation by Er3+-CdS/MoS2 (ECMS) was investigated under ultrasonic and light conditions. The degradation reaction rate of 17ß-E2 was increased from (14.414 ± 0.315) × 10-3 min-1 to (122.677 ± 1.729) × 10-3 min-1 within 90 min sonophotocatalytic (SPC) reaction with the addition of HA. The results of quenching coupled with chemical probe experiments indicated that more reactive intermediates (RIs) including reactive oxygen species (ROSs) and triplet-excited states were generated in the HA-enhanced sonophotocatalytic system. The triplet-excited states of humic acid (3HA*), hydroxyl radical (•OH), and superoxide radical (•O2-) were the dominant RIs for 17ß-E2 elimination. In addition, the energy- and electron-transfer process via coexisting HA also account for 12.86% and 29.24% contributions, respectively. The quantum yields of RIs in the SPC-ECMS-HA system followed the order of 3HA* > H2O2 > 1O2 > â€¢O2-> •OH. Moreover, the spectral and fluorescence characteristics of HA were further analyzed during the sonophotocatalytic reaction process. The study expanded new insights into the comprehension of the effects of omnipresent coexisting HA and RIs formation for the removal of 17ß-E2 during the sonophotocatalytic process.


Assuntos
Substâncias Húmicas , Poluentes Químicos da Água , Peróxido de Hidrogênio , Estradiol , Espécies Reativas de Oxigênio , Superóxidos , Poluentes Químicos da Água/análise
3.
Environ Res ; 204(Pt A): 112032, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34516980

RESUMO

A novel FeVO4/BiVO4 heterojunction photocatalyst was synthesized by hydrothermal method. The FeVO4/BiVO4 nanostructures were characterized by XRD, SEM, XPS, UV-vis, and photoluminescence spectroscopy. The effects of catalyst dosage, contaminant concentration, initial hydrogen peroxide (H2O2) concentration, and pH value on the degradation of levofloxacin were investigated and several repeated experiments were conducted to evaluate the stability and reproducibility. The optimized process parameters were used for mineralization experiments. Reactive oxygen species, degradation intermediates, and possible catalytic mechanisms were also investigated. The results showed that the sonophotocatalytic performance of the FeVO4/BiVO4 heterojunction catalyst was better than that of sonocatalysis and photocatalysis. In addition, the Type II heterojunction formed by the material still had good stability in the degradation of levofloxacin after 5 cycles. The possible degradation pathway and mechanism of levofloxacin by sonophotocatalysis were put forward. This work develops new sono-photo hybrid process for potential application in the field of wastewater treatment.


Assuntos
Peróxido de Hidrogênio , Levofloxacino , Catálise , Cinética , Reprodutibilidade dos Testes
4.
Opt Express ; 29(20): 31324-31336, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615227

RESUMO

In this paper, we have proposed and experimentally demonstrated a multiplexed sensing interrogation technique based on a flexibly switchable multi-passband RF filter with a polarization maintaining fiber (PMF) Solc-Sagnac loop. A high-order Solc-Sagnac loop can be used as a spectrum slicer as well as sensing heads, and a multi-passband microwave photonic filter (MPF) can be achieved together with a dispersive medium. Environmental parameter variations will cause a frequency shift of the corresponding passband of the MPF, so by employing only one Sagnac loop, it is possible to monitor several environmental parameters simultaneously. In this article, we have demonstrated and analyzed the performance of the flexibly switchable multi-passband MPF by using a second-order Solc-Sagnac loop. To demonstrate the temperature sensing capabilities of our interrogation system, we have applied temperature changes individually to Sensor Head 1 (L P M F 1 ≈0.97m) only, Sensor Head 2 (L P M F 2 ≈2.97m) only, and both Sensor Head 1 and 2 in the experiment. By monitoring frequency shift of the MPF's passbands, the sensitivities for Sensor Head 1 and Sensor Head 2 have been estimated to be -0.275 ± 0.011 MHz/℃ and -0.811 ± 0.013 MHz/℃ respectively, which show a good sensing linearity and stability. By utilizing the longer length of the sensing PMF, higher sensitivity can be achieved. By using Solc-Sagnac loop with higher order, more sensors can be multiplexed.

5.
Microsc Microanal ; 19(1): 190-200, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23351492

RESUMO

It is well known that extracellular signal-regulated kinase 8 (ERK8) plays pivotal roles in various mitotic events. But its physiological roles in oocyte meiotic maturation remain unclear. In this study, we found that although no specific ERK8 signal was detected in oocyte at the germinal vesicle stage, ERK8 began to migrate to the periphery of chromosomes shortly after germinal vesicle breakdown. At prometaphase I, metaphase I (MI), anaphase I, telophase I, and metaphase II (MII) stages, ERK8 was stably detected at the spindles. By taxol treatment, we clarified that the ERK8 signal was stained on the spindle fibers as well as microtubule asters in MI and MII oocytes. In fertilized eggs, the ERK8 signal was not observed in the two pronuclei stages. At prometaphase, metaphase, and anaphase of the first mitosis, ERK8 was detected on the mitotic spindle. ERK8 knock down by antibody microinjection and specific siRNA caused abnormal spindles, failed chromosome congression, and decreased first polar body extrusion. Taken together, our results suggest that ERK8 plays an important role in spindle organization during mouse oocyte meiotic maturation and early embryo cleavage.


Assuntos
Embrião de Mamíferos/citologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Meiose , Oócitos/crescimento & desenvolvimento , Fuso Acromático/metabolismo , Animais , Camundongos , Fuso Acromático/química
6.
Cell Cycle ; 11(23): 4366-77, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23159858

RESUMO

Nek9 (also known as Nercc1), a member of the NIMA (never in mitosis A) family of protein kinases, regulates spindle formation, chromosome alignment and segregation in mitosis. Here, we showed that Nek9 protein was expressed from germinal vesicle (GV) to metaphase II (MII) stages in mouse oocytes with no detectable changes. Confocal microscopy identified that Nek9 was localized to the spindle poles at the metaphase stages and associated with the midbody at anaphase or telophase stage in both meiotic oocytes and the first mitotic embyros. Depletion of Nek9 by specific morpholino injection resulted in severely defective spindles and misaligned chromosomes with significant pro-MI/MI arrest and failure of first polar body (PB1) extrusion. Knockdown of Nek9 also impaired the spindle-pole localization of γ-tubulin and resulted in retention of the spindle assembly checkpoint protein Bub3 at the kinetochores even after 10 h of culture. Live-cell imaging analysis also confirmed that knockdown of Nek9 resulted in oocyte arrest at the pro-MI/MI stage with abnormal spindles, misaligned chromosomes and failed polar body emission. Taken together, our results suggest that Nek9 may act as a MTOC-associated protein regulating microtubule nucleation, spindle organization and, thus, cell cycle progression during mouse oocyte meiotic maturation, fertilization and early embryo cleavage.


Assuntos
Oócitos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fuso Acromático/metabolismo , Animais , Antineoplásicos Fitogênicos/farmacologia , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona , Segregação de Cromossomos , Cromossomos/metabolismo , Feminino , Cinetocoros/metabolismo , Pontos de Checagem da Fase M do Ciclo Celular , Meiose , Camundongos , Camundongos Endogâmicos ICR , Mitose , Morfolinos/farmacologia , Quinases Relacionadas a NIMA , Nocodazol/farmacologia , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Paclitaxel/farmacologia , Proteínas de Ligação a Poli-ADP-Ribose , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Tubulina (Proteína)/metabolismo
7.
Cell Cycle ; 11(10): 1948-55, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22544319

RESUMO

Checkpoint kinase 1 (Chk1) plays key roles in all currently defined cell cycle checkpoints, but its functions in mouse oocyte meiosis remain unclear. In this study, we report the expression, localization and functions of Chk1 in mouse oocyte meiosis. Chk1 was expressed from germinal vesicle (GV) to metaphase II (MII) stages and localized to the spindle from pro-metaphase I (pro-MI) to MII stages in mouse oocytes. Chk1 depletion facilitated the G 2/M transition while Chk1 overexpression inhibited the G 2/M transition as indicated by germinal vesicle breakdown (GVBD), through regulation of Cdh1 and Cyclin B1. Chk1 depletion did not affect meiotic cell cycle progression after GVBD, but its overexpression after GVBD activated the spindle assembly checkpoint and prevented homologous chromosome segregation, thus arresting oocytes at pro-MI or metaphase I (MI) stages. These results suggest that Chk1 is indispensable for prophase I arrest and functions in G 2/M checkpoint regulation in meiotic oocytes. Moreover, Chk1 overexpression affects meiotic spindle assembly checkpoint regulation and thus chromosome segregation.


Assuntos
Meiose , Oócitos/enzimologia , Proteínas Quinases/metabolismo , Animais , Proteínas Cdh1 , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Quinase 1 do Ponto de Checagem , Segregação de Cromossomos , Ciclina B1/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular , Pontos de Checagem da Fase M do Ciclo Celular , Prófase Meiótica I , Metáfase , Camundongos , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Proteínas Quinases/química , Proteínas Quinases/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo
8.
Cell Cycle ; 11(4): 818-26, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22313732

RESUMO

Synaptotagmin1, a calcium sensor for exocytosis, forms the 7S complex, or so-called SNARE protein complex, together with SNAP -25, syntaxin and synaptobrevin to mediate docking and fusion of synaptic vesicles to the plasma membrane of the nerve terminal. Here, we identified the unique localization, expression and function of Syt1 during mouse oocyte meiotic maturation by using confocal microscopy, western blotting, Morpholino-based knockdown and time-lapse live cell imaging. We showed that Syt1 expression was gradually increased during oocyte maturation. Syt1 was localized at the oocyte cortex from GV to MII stages and at the spindle poles in MI and MII phases, with one third of a signal-free zone at the oocyte cortex, where the chromosomes are located, which is similar to the distribution pattern of CGs from the pro-MI to MII stages. Knockdown of Syt1 resulted in pro-MI/MI arrest and PB1 extrusion decrease, with severely disrupted spindles and misaligned chromosomes. Knockdown of Syt1 also caused abnormal localization of γ-tubulin, which became redistributed into the cytoplasm. Chromosome spreading showed failure of homologous chromosome segregation. The spindle assembly checkpoint protein Bub3 was detected at the kinetochores even after 10 h of oocyte culture. Live cell imaging analysis revealed that knockdown of Syt1 resulted in abnormal spindles with various morphologies and chromosomes arrested at the pro-MI/MI stage. Defective spindles failed to support chromosome alignment along microtubules, which led to repetitive unsuccessful metaphase-anaphase transitions and failure of PB1 extrusion after extended culture. Taken together, we suggest that Syt1 may act as a MTOC-associated protein to play important roles in mouse oocyte spindle organization/stability, and that it is indispensable for the metaphase-anaphase transition to promote mouse oocyte meiotic maturation.


Assuntos
Anáfase/genética , Metáfase/genética , Oócitos/citologia , Oócitos/metabolismo , Fuso Acromático/metabolismo , Sinaptotagminas/metabolismo , Animais , Células Cultivadas , Immunoblotting , Camundongos , Microscopia Confocal , Fuso Acromático/genética , Sinaptotagminas/genética
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