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1.
Reprod Fertil Dev ; 34(6): 516-525, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35296374

RESUMO

Extensive knowledge of follicular development is imperative for improving egg production in chickens. The functional role of follicles to produce oocytes (eggs) is well recognised; however, specific markers associated with follicle development have been poorly explored. Therefore, a tandem mass tag based proteomic technique was used to identify the status of the proteome of small white follicles (1-4mm) and small yellow follicles (6-8mm). Analysis of differentially expressed proteins (DEP, Fold Change>1.2, P -value<0.05) demonstrated a total of 92 proteins (n =92), of which 35 (n =35) were upregulated and 57 were downregulated. DEP were further used for gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathways. The GO analysis found that DEP were mainly associated with the RNA metabolic process, cellular component organisation, peptide biosynthetic process and protein folding, thereby suggesting a key role in the follicle development process. Kyoto Encyclopedia of Genes and Genomes enrichment pathway analysis of the DEP substantiated the findings of GO analysis and described that DEP are involved in regulation of the cytoskeleton, carbon metabolism and amino acid biosynthesis. The validation of proteomic data through real-time quantitative polymerase chain reaction suggested HSPA8, HSPA2, SOD1 and FKPB3 as potential markers of small white and small yellow follicle development. This study demonstrates an understanding of proteome dynamics and represents the most comprehensive information on the entire Guangxi Ma chicken follicular proteome.


Assuntos
Galinhas , Proteômica , Animais , China , Perfilação da Expressão Gênica/veterinária , Proteoma
2.
Small ; 17(52): e2102392, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34636135

RESUMO

The unique structural advantage and physicochemical properties render some 2D materials emerging platforms for intracellular bioimaging, biosensing, or disease theranostics. Despite recent advances in this field, one major challenge lies in bypassing the endocytic uptake barrier to allow internalization of very large 2D materials that have longer retention time in cells, and hence greater potency as intracellular functional platforms than small, endocytosable counterparts. Here, an engineered cucurbit[6]uril carrying at its periphery multiple spiropyran pendants that readily translocates into cytosol, and then polymerizes laterally and non-covalently in a controlled manner, enabling direct generation of 2D materials inside living cells, is reported. The resultant 2D materials are single-monomer-thick and can in situ grow up to 0.8-1.2 µm in lateral size, experimentally proved too large to be endocytosed from outside the cells even after surface engineered with biorecognition entities. A Förster resonance energy transfer assay is further devised for real-time visualization of the polymerization dynamics in vivo, clearly demonstrating the rationale in this study. With the otherwise non-endocytosable large 2D materials gaining access to cytosol, potent intracellular signaling or theranostic platform that surpasses the intrinsic performance limit of conventional small counterparts are in sight.


Assuntos
Hidrocarbonetos Aromáticos com Pontes , Imidazóis , Benzopiranos , Indóis , Nitrocompostos
3.
Mol Cell Proteomics ; 17(10): 1875-1891, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30002204

RESUMO

Maternal-effect genes are especially critical for early embryonic development after fertilization and until massive activation of the embryonic genome occurs. By applying a tandem mass tag (TMT)-labeled quantitative proteomics combined with RNA sequencing approach, the proteome of the buffalo was quantitatively analyzed during parthenogenesis of mature oocytes and the two-cell stage embryo. Of 1908 quantified proteins, 123 differed significantly. The transcriptome was analyzed eight stages (GV, MII, 2-cell, 4-cell, 8-cell, 16-cell, morula, blastocyst) of Buffalo using the RNA sequencing approach, and a total of 3567 unique genes were identified to be differently expressed between all consecutive stages of pre-implantation development. Validation of proteomics results (TUBB3, CTNNA1, CDH3, MAP2K1), which are involved in tight junction and gap junction, revealing that the maternal expression of the proteins possibly plays a role in the formation of cellular junctions firstly after parthenogenetic activation. Correlation and hierarchical analyses of transcriptional profiles and the expression of NPM2 and NLRP5 mRNA of buffalo in vitro developed oocytes and parthenogenetic embryos indicated that the "maternal-to-zygotic transition" (MZT) process might exist in the model of parthenogenesis, which is similar to a normally fertilized embryo, and may occur between the 8-cell to 16-cell stage. These data provide a rich resource for further studies on maternal proteins and genes and are conducive to improving nuclear transfer technology.


Assuntos
Búfalos/genética , Búfalos/metabolismo , Perfilação da Expressão Gênica , Oócitos/metabolismo , Partenogênese/genética , Proteoma/metabolismo , Proteômica/métodos , Animais , Embrião de Mamíferos/metabolismo , Feminino , Junções Comunicantes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Junções Íntimas/metabolismo , Regulação para Cima
4.
Reprod Domest Anim ; 55(12): 1764-1773, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33031588

RESUMO

The comprehensive understanding of early embryo development is essential to optimize in vitro culture conditions. Protein expression landscape of parthenogenetically produced embryo remains unexplored. This study aimed to investigate the protein expression dynamics with a particular focus on energy metabolism throughout the early developmental stages of parthenogenetic buffalo embryos. For this purpose, we performed iTRAQ-based quantitative mass spectrometry and identified 280 proteins common in all stages. A total of 933 proteins were identified during the proteomics analysis. The data depicted that morula and blastocyst had distinct protein expression dynamics as compared to 2- to 16-cell-stage embryo. KEGG pathway analysis showed 23 proteins belonging to energy metabolism appeared in the data. Study of energy metabolism-related protein's expression pattern demonstrated that there was asynchrony in proteins related to glycolysis throughout the examined developmental stages. The expression pattern of pyruvate kinase mutase (PKM), an essential protein of glycolysis, indicated a slightly decreasing trend from 2-cell-stage embryo to blastocyst, and it was supported by expression of proteins involved in lactate production (LDHA and LDHB) suggesting the decreasing rate of aerobic glycolysis (Warburg Effect) at morula and blastocyst stage. The increased Warburg Effect is considered as the hallmark of proliferating cells or embryo at the blastocyst stage. Furthermore, the proteins involved in the citric acid cycle also showed down-regulation at the blastocyst stage, indicating a lesser role of oxidative phosphorylation at this stage. Therefore, it could be divulged from the study that there may be an irregular pattern of energy metabolism in early parthenogenetic embryos. Further studies are recommended to understand this phenomenon.


Assuntos
Búfalos/embriologia , Desenvolvimento Embrionário/fisiologia , Metabolismo Energético , Proteoma/metabolismo , Animais , Búfalos/metabolismo , Ciclo do Ácido Cítrico/fisiologia , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/fisiologia , Feminino , Glicólise/fisiologia , Partenogênese
5.
Reprod Domest Anim ; 55(9): 1115-1123, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32564396

RESUMO

Buffalo is considered short-day breeder in tropical and subtropical part of the world and seasonality and photoperiodism impart major influence on its fertility. However, its impact on in vitro embryo production (IVEP) remains elusive. Therefore, this study investigated the effect of seasonal variations and photoperiodism on morphological and molecular parameters of IVEP in buffalo. For this purpose, we conducted two different experiments on the oocytes obtained by aspirating follicles from abattoir derived ovaries. In Exp. I, retrospective analysis was performed for oocyte recovery, blastocyst and hatching rate, during four consecutive seasonal periods (i.e. January-March, April-June, July-September and October-December). In Exp. II, oocytes from peak breeding and non-breeding seasons were subjected to 24 hr in vitro maturation and evaluated for polar body extrusion to assess maturation rate. Results showed that embryo development was markedly low during second quarter (April-June) and maximum during fourth quarter (October-December) of the year; referred as non-breeding and breeding seasons, respectively. Comparative data analysis demonstrated that poor oocyte quality is major reason for lesser efficiency of embryo production during non-breeding season than peak breeding season as suggested by poor oocyte recovery (2.31 ± 0.10 vs. 3.65 ± 0.27) and maturation rate (33.32 ± 2.1 vs. 63.15 ± 7.31). Subsequently, comparative gene expression analysis of blastocysts during peak breeding season significantly upregulated pluripotency gene (OCT-4) and downregulated heat shock protein 90, as compared to non-breeding season. Therefore, it could be divulged from the present study that seasonal variations and photoperiodism have profound effect on oocyte quality and subsequent embryo development. It is recommended to find suitable additives for in vitro maturation that could mitigate seasonal effects.


Assuntos
Búfalos/fisiologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/crescimento & desenvolvimento , Fotoperíodo , Estações do Ano , Animais , Desenvolvimento Embrionário , Feminino , Fertilização in vitro/veterinária , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP90/genética , Masculino , Fator 3 de Transcrição de Octâmero/genética , Oócitos/fisiologia
6.
Reprod Domest Anim ; 55(4): 503-514, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31971628

RESUMO

Maternal mRNAs deposited in the egg during oogenesis are critical during the development of early embryo, before the activation of the embryonic genome. However, there is little known about the dynamic expression of maternally expressed genes in mammals. In this study, we made buffalo parthenogenesis as our research model to analyse maternal transcription profiles of pre-implantation embryo in buffalo using RNA sequencing. In total, 3,567 unique genes were detected to be differentially expressed among all constant stages during early embryo development (FPKM > 0). Interestingly, a total of 10,442 new genes were discovered in this study, and gene ontology analysis of the new differentially expressed genes indicated that the new genes have a wide cellular localization and are involved in many molecular functions and biological processes. Moreover, we identified eight clusters that were only highly expressed in a particular developmental stage and enriched a number of GO terms and KEGG pathways that were related to specific stage. Furthermore, we identified 1,530 hub genes (or key members) from the maternally expressed gene networks, and these hub genes were involved in 11 stage-specific modules. After visualization using Cytoscape 3.2.1 software, we obtained complex interaction network of hub genes, indicating the highly efficient cooperation between genes during the development in buffalo embryos. Further research of these genes will greatly deepen our understanding of embryo development in buffalo. Collectively, this research lays the foundation for future studies on the maternal genome function, buffalo nuclear transfer and parthenogenetic embryonic stem cells.


Assuntos
Búfalos/embriologia , Búfalos/genética , Perfilação da Expressão Gênica , Animais , Búfalos/metabolismo , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Maturação in Vitro de Oócitos/veterinária , Partenogênese/genética , Análise de Sequência de RNA
7.
Int J Mol Sci ; 21(6)2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32183390

RESUMO

The molecular mechanism regulating embryo development under reduced oxygen tension remains elusive. This study aimed to identify the molecular mechanism impacting embryo development under low oxygen conditions. Buffalo embryos were cultured under 5% or 20% oxygen and were evaluated according to their morphological parameters related to embryo development. The protein profiles of these embryos were compared using iTRAQ-based quantitative proteomics. Physiological O2 (5%) significantly promoted blastocyst yield, hatching rate, embryo quality and cell count as compared to atmospheric O2 (20%). The embryos in the 5% O2 group had an improved hatching rate of cryopreserved blastocysts post-warming (p < 0.05). Comparative proteome profiles of hatched blastocysts cultured under 5% vs. 20% O2 levels identified 43 differentially expressed proteins (DEPs). Functional analysis indicated that DEPs were mainly associated with glycolysis, fatty acid degradation, inositol phosphate metabolism and terpenoid backbone synthesis. Our results suggest that embryos under physiological oxygen had greater developmental potential due to the pronounced Warburg Effect (aerobic glycolysis). Moreover, our proteomic data suggested that higher lipid degradation, an elevated cholesterol level and a higher unsaturated to saturated fatty acid ratio might be involved in the better cryo-survival ability reported in embryos cultured under low oxygen. These data provide new information on the early embryo protein repertoire and general molecular mechanisms of embryo development under varying oxygen levels.


Assuntos
Anaerobiose/fisiologia , Blastocisto/citologia , Búfalos/embriologia , Desenvolvimento Embrionário/fisiologia , Metabolismo dos Lipídeos/fisiologia , Animais , Colesterol/análise , Embrião de Mamíferos/metabolismo , Ácidos Graxos/metabolismo , Fertilização in vitro/métodos , Glicólise/fisiologia , Fosfatos de Inositol/metabolismo , Estresse Oxidativo/fisiologia , Oxigênio/metabolismo , Terpenos/metabolismo
8.
Gastroenterol Nurs ; 43(6): 440-447, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33259432

RESUMO

The Chicago classification diagnostic criteria of esophageal motility disorders are based on 5-ml water swallows in the supine position and have not been analyzed for the correlation between the morphology and bolus transit in the upright position and larger volume swallow conditions. This study aimed to evaluate the effect of posture and swallow volume on peristaltic morphology and the probability of bolus clearance in patients with nonspecific esophageal disorder. A total of 139 patients (4,214 swallows) were included for high-resolution impedance manometry analysis in the right lateral recumbent and upright positions, as well as 5- and 10-ml liquid swallows. Intact peristalses were more frequent in the right lateral recumbent position than in the upright position. No difference was reported on failed peristalsis between both positions. Breaks were more frequent in the upright position. A 20 mmHg isobaric contour (compared with 30 mmHg) was associated with decreased bolus clearance. Bolus clearance probability with 10-ml swallows is greater than that with 5-ml swallows. There was no significant difference in the total bolus clearance comparing between the right lateral recumbent and upright positions. The right lateral recumbent position was associated with a higher intact peristalsis. The volume of swallow did not affect the integrality of esophageal peristalsis but did improve the bolus clearance.


Assuntos
Deglutição , Esôfago , Impedância Elétrica , Humanos , Manometria , Postura , Probabilidade
9.
Dig Endosc ; 26(1): 15-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24118211

RESUMO

Endoscopic retrograde cholangiopancreatography (ERCP) has become a primary tool for the treatment of biliary and pancreatic ductal diseases. It is essential for the endoscopist carrying out the ERCP to have a thorough understanding of the potential adverse events. Typically, endoscopists are well familiar with common adverse events such as post-ERCP pancreatitis, cholangitis, post-sphincterotomy bleeding, post-sphincterotomy perforation, and sedation-related cardiopulmonary compromises. However, there are other less common adverse events that arecritical to promptly recognize in order to provide appropriate therapy and prevent disastrous outcomes. This review focuses on the presentation and management of the less common and rare adverse events of an ERCP from the perspective of the practicing endoscopist.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Embolia Aérea/diagnóstico , Cálculos Biliares/complicações , Hemobilia/etiologia , Humanos , Íleus/etiologia , Lacerações/etiologia , Ruptura , Esfinterotomia Endoscópica/efeitos adversos , Baço/lesões
10.
Theriogenology ; 222: 22-30, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38615433

RESUMO

Primordial germ cells (PGCs) are the precursors of germ cells and play a crucial role in germline transmission. In chickens, PGCs can be cultured in vitro while maintaining their germline stem cell characteristics. The Deleted in Azoospermia-Like (DAZL) gene, which is highly expressed in PGCs, is essential for germ cell development. Here, through gene knockout experiments, we discovered that the loss of DAZL expression in chicken PGCs led to decreased proliferation and survival. By next employed techniques such as RIP-seq (RNA Binding Protein Immunoprecipitation) and Co-IP-MS/MS (Co-immunoprecipitation Mass Spectrometry), we identified genes directly regulated by DAZL or cooperating with DAZL at the transcriptomic and proteomic levels. DAZL was found to control genes related to germline development, pluripotency, and cell proliferation in PGCs. Additionally, we observed a significant overlap between RNAs and proteins that interact with both DAZL and DDX4, indicating their cooperation in the gene regulation network in chicken PGCs. Our research provides valuable insights into the function of the DAZL gene in germline cells.


Assuntos
Proliferação de Células , Galinhas , RNA Helicases DEAD-box , Células Germinativas , Proteínas de Ligação a RNA , Animais , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Galinhas/genética , Células Germinativas/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Regulação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento
11.
Pharmazie ; 68(5): 369-75, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23802436

RESUMO

Kushen, the dried root of Sophora flavescens Ait, is a traditional Chinese herbal medicine. Kushen alkaloids have been developed in China as anticancer drugs, and more potent antitumor activities have been identified in kushen flavonoids than in kushen alkaloids. In this study, the anti-angiogenic properties of (2S)-7,2',4'-triihydroxy-5-methoxy-8-dimethylallyl flavanone (Compound 1, a novel flavonoid isolated from Kushen), were examined using the human umbilical vein endothelial cell line (ECV304) in vitro. The results indicated that compound 1 shows anti-angiogenesis activity via inhibitory effects on cell proliferation, cell migration, cell adhesion, and tube formation. Further studies indicated that compound 1 blocks cell cycles in the G0/G1 phase without inducing apoptosis, and down regulates vascular endothelial growth factor (VEGF) expression. The free radical scavenging activity of compound 1 was found through 2',7'-dichlorofluorescin diacetate (DCFH-DA) incubation assay in cells. The anti-angiogenic properties of compound 1 and its antiproliferative effect on endothelial cells without causing apoptosis make it a good candidate for development as a agent against development of tumors.


Assuntos
Inibidores da Angiogênese/farmacologia , Flavonoides/farmacologia , Fase G1/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Sophora/química , Fator A de Crescimento do Endotélio Vascular/biossíntese , Antioxidantes/farmacologia , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas , Células Endoteliais/efeitos dos fármacos , Flavonoides/isolamento & purificação , Humanos , Microtúbulos/efeitos dos fármacos , Raízes de Plantas/química , Espécies Reativas de Oxigênio/metabolismo
12.
Poult Sci ; 102(8): 102815, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37356301

RESUMO

Germ cell loss is a crucial biological event during germ cell development. The number of female germ cells determines the reproductive performance and egg production of hens. Various intrinsic and extrinsic factors affect germ cell loss, such as germ cell nest breakdown in early life and nutritional deficiencies during daily husbandry. Here, we examined the effect of fasting on the germ cell number of chicks. The results showed that 72 h fasting resulted in a higher germ cell loss than that by 24 h fasting in chicks. The RNA-seq analysis revealed that the genes of ribosome pathway were down-regulated and the biological processes of protein processing in endoplasmic reticulum were inhibited in starved chicks. Furthermore, in female chicks treated with 72 h fasting, the qPCR of ovaries showed down-regulation of ribosome-related genes, and transmission electron microscopy imaging of ovaries showed fewer ribosomes. The blood biochemical indices indicated that 72 h fasting reduced the liver functions and affected the glucose metabolism, lipid metabolites and ion metabolites. In summary, the present results concluded negative impacts on the germ cell pool by prolonged fasting in the early life of chicks and manifested that adequate management should be cared for fasted time for breeding.


Assuntos
Galinhas , Jejum , Animais , Feminino , Galinhas/fisiologia
13.
Poult Sci ; 102(3): 102377, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36586387

RESUMO

In hens, egg production depends on the development of germ cells in the ovary. Germ cells are established before birth, and their number gradually decreases during their lifespan. Therefore, it is essential to determine the time points of massive germ cell loss and the underlying mechanism. In this study, a gene-edited chicken with mCherry fluorescence specifically expressed in the germline was generated by the integration of the mCherry gene into the 3'-end of the DAZL locus, which facilitated the isolation of germ cells from the gonads of DAZL-mCherry embryos or chicks and quantification using flow cytometry based on the observation of red fluorescence. The results demonstrated the dynamics of germ cell development from embryos at 17 d of hatching (dh) to chickens at 7 d post-hatch (dph) and revealed a substantial loss of germ cells in the late embryonic stage (18 -19 dh) and post-hatch period (2 -3 dph). Additionally, the number of germ cells in DAZL × Guangxi Ma chicken was significantly higher than that in DAZL × Lohmann Pink chicken at 19 dh and 3 dph (P < 0.05). Furthermore, the numbers of germ cells positively correlated with the body weight in DAZL × Lohmann Pink chicken. In conclusion, our results showed the dynamics of germ cell development in chicken ovaries during peri-hatch periods and indicated the time point of substantial germ cell loss. The results provide evidence for further exploration of the underlying mechanism and serve as a reference for chicken breeding and management.


Assuntos
Galinhas , Edição de Genes , Animais , Feminino , Galinhas/genética , Edição de Genes/veterinária , China , Gônadas , Células Germinativas
14.
Invest Ophthalmol Vis Sci ; 63(6): 2, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35648639

RESUMO

Purpose: To characterize the distribution of pigment particles in aqueous drainage structures of DBA/2J mice with different intraocular pressure (IOP) levels. Methods: DBA/2J mice were monitored from 9 to 44 weeks of age. IOP measurements were performed periodically. At 12, 20, 28, and 36 weeks, three mice were randomly selected for each time point and divided into three IOP groups. The morphology, size, and quantity of pigment particles in aqueous drainage structures were determined via transmission electron microscopy combined with ImageJ-based analysis. Between-group differences were evaluated with a one-way analysis of variance and Fisher's least significant difference test. Results: In the anterior chamber, 74.2% (187/252) of pigment particles were round (diameter range, 0.20-0.73 µm), and 25.8% (65/252) were oval (length range, 0.35-1.20 µm ). In the high-IOP group (IOP≥15 mmHg), pigment particles in the trabecular meshwork (TM) were more abundant and larger in size than those in the normal-IOP group (P<0.001). All separate pigment particles in the TM of the high-IOP group were >0.4  µm in size. The diameters of round (IOP≤10 mmHg, 0.44±0.13 µm; IOP between 10 and 15 mmHg, 0.57±0.13 µm; IOP≥15 mmHg, 0.61±0.12 µm) and the lengths of oval (0.65±0.14 µm vs. 0.77±0.12 µm vs. 0.88±0.15 µm, respectively) pigment particles in the TM differed among groups (F=27.258 and F=27.295, respectively; both P<0.001). No such differences were discovered in the iris and around Schlemm's canal (P>0.05). Conclusions: In DBA/2J mice, large and medium pigment particles (>0.4 µm) seem to play an important role in causing aqueous outflow obstruction and IOP elevation.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Animais , Modelos Animais de Doenças , Pressão Intraocular , Camundongos , Camundongos Endogâmicos DBA , Tonometria Ocular , Malha Trabecular
15.
Front Psychol ; 13: 1003739, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248490

RESUMO

It has been a growing trend in Chinese universities to shift from English for general purposes (EGP) to English for specific purposes (ESP) teaching. Against this background, large groups of teachers previously engaged in teaching EGP have become or are becoming ESP teachers, which means a complex process of learning for subject-specific information, transforming teaching practices and constructing new identities. Despite this, very little has been written about the ESP teacher cognition (TC) of language teaching or the factors influencing this shift in teaching. This study involved English for Medical Purposes (EMP) teachers in Chinese universities as participants, and a scale of EMP TC with 31 items was developed on the basis of questionnaire results. Data from exploratory factor analysis revealed six dimensions of the scale, namely, teacher attitude, teacher belief, teacher learning, teacher support, role identification, and teacher practice-that combine to constitute and influence EMP TC. While the identity factor has attracted wide attention in ESP teacher research, other factors have largely been neglected. Thus, this research highlights the importance of more factors in shaping and changing the language teaching cognition of EMP or ESP teachers in large, especially the teacher belief factor. In addition, results of independent samples t-tests indicated significant difference in EMP teacher learning in terms of gender, differences in EMP teacher attitude and teacher support in terms of EMP teaching experience. Suggestions for enhancing EMP TC are offered on the basis of the conclusions of this research.

16.
Front Psychol ; 13: 1082228, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36704688

RESUMO

Lexical richness, a crucial aspect of L2 writing research, has been shown to make a difference in L2 writing performance. Nonetheless, the majority of empirical studies have focused either on a single text type or on the comparison between narrative and non-narrative writing (mostly argumentative writing) in academic contexts, whereas there has been a dearth of research regarding the lexical features pertaining to varied non-narrative writing genres. Considering the cognitive demands intrinsic in different writing task types, this study examined the development of lexical richness, which includes lexical density, lexical variation, and lexical sophistication, in Chinese EFL students' argumentative and expository compositions over the course of one academic year. Fifty-four participants were asked to write eight compositions (in two alternating genres)-four argumentative and four expository-which were parsed using two computational tools. The results indicated a significant increase in all three subconstructs of lexical richness in argumentative compositions over the year, while in expository compositions, only lexical density and lexical sophistication demonstrated an increasing trend. As time went on, the participants in both genres tended to use more high-frequency words with more senses, more academic words, more high-frequency bigrams, and words that are less familiar and more precise. Moreover, the argumentative compositions displayed higher lexical density than the expository ones, while the expository compositions manifested greater lexical variation and lexical sophistication than the argumentative ones. The findings of the study suggest some implications for L2 writing teaching and research.

17.
Front Psychol ; 13: 1047117, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438404

RESUMO

Genre researchers have found that writing in different genres involves different cognitive task loads and requires different linguistic demands. Generally speaking, narratives involve the description of events with a focus on people and their actions within a specific time frame, whereas non-narrative genres focus on making an argument or discussing ideas or beliefs in a logical fashion, thus resulting in distinct language features. However, the vast majority of genre-based studies have either focused on one single genre or made comparisons between narrative and non-narrative writing (mostly argumentative) in academic contexts without examining how EFL writers perform across non-narrative genres. Moreover, the measures used in quantifying the syntactic complexity of writing are varied, leading to inconsistent findings. This study investigated the effects of genre on the syntactic complexity of writing through comparing argumentative and expository compositions written by Chinese English-as-a-foreign-language (EFL) learners over one academic year. Fifty-two participants were asked to write eight compositions (with two genres alternated), four argumentative and four expository, which were parsed via the Syntactic Complexity Analyzer. The results with time as the within-subjects variable showed a significant development of syntactic complexity in both argumentative and expository compositions over one academic year. Meanwhile, the paired-sample t-test with genre as the within-subjects variable exhibited a higher syntactic complexity in argumentative compositions than in expository ones on most of the 14 measures examined at four time points over the year. Additionally, a two-way repeated measures analysis of variance with genre and time as independent variables ascertained an interactional effect of time and genre on some of the 14 measures. The present study tested and verified the impact genre exerts on the syntactic complexity of writing, providing implications for teachers to be more informed in teaching and assessing EFL writing and for students to be more conscious of genre difference in EFL writing.

18.
Medicine (Baltimore) ; 100(31): e26567, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34397796

RESUMO

ABSTRACT: To report the changes of trabecular meshwork (TM) pigmentation and clinical outcomes of patients with pigment dispersion syndrome (PDS) after resolution of reverse pupillary block.Twenty one eyes of 11 PDS patients were followed up periodically for 15 years after resolution of reverse pupillary block with either Nd: YAG laser peripheral iridotomy (LPI) or trabeculectomy. Visual acuity (VA), best-corrected visual acuity (BCVA), slit lamp examination, intraocular pressure (IOP), Humphrey visual field analysis (VFA), gonioscopy and stereoscopic funduscopy were performed on admission and every 6 months postoperatively. TM pigmentation was quantitatively evaluated and graded every 5 years after the treatment, in which the circumference of anterior chamber angle was divided into 4 quadrants: superior, inferior, nasal and temporal. Postoperative IOP, VA, BCVA, VFA, TM pigmentation and adjunctive anti-glaucoma medications were main outcome measurements and compared with baseline.Eleven patients (9 males, 2 females) were identified as PDS according to the diagnostic criteria, with average age of 38.25 ±â€Š6.93 years (range, 31-55 years) at initial diagnosis. The mean IOP level was 33.1 ±â€Š9.8 mmHg (range, 22-56 mmHg) at diagnosis. Ten PDS eyes received LPI, and the other eleven eyes underwent uneventful trabeculectomy. The median TM pigmentation score of the 21 PDS eyes was 16 (interquartile range [IQR], 15-16) on admission, which changed to 14 (IQR, 13-15), 13 (IQR, 12-14), 12(IQR, 10.5-12) at 5-, 10-, 15-year follow-up visits respectively. The decrease rate of TM pigmentation was 37% in inferior quadrant, while in nasal, temporal, and superior quadrant the reduction rate was 28%, 23%, and 18%, respectively, at the last follow-up visit. Majority of these enrolled eyes (19/21) had stable VA and BCVA with average endpoint IOP of 15.1 ±â€Š3.4 mmHg.TM pigmentation in PDS patients attenuates with time after reverse pupillary block was resolved, in which the inferior quadrant seems faster than the other quadrants.


Assuntos
Glaucoma de Ângulo Aberto/fisiopatologia , Pigmentação , Malha Trabecular/fisiopatologia , Adulto , Feminino , Seguimentos , Glaucoma de Ângulo Aberto/diagnóstico , Glaucoma de Ângulo Aberto/cirurgia , Humanos , Pressão Intraocular , Iris , Lasers de Estado Sólido/uso terapêutico , Masculino , Pessoa de Meia-Idade , Epitélio Pigmentado Ocular , Trabeculectomia , Ultrassonografia
19.
Animals (Basel) ; 11(4)2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33924300

RESUMO

Follicles' development in chicken imparts a major impact on egg production. To enhance the egg-laying efficiency, comprehensive knowledge of different phases of follicular development is a prerequisite. Therefore, we used the tandem mass tag (TMT) based proteomic approach to find the genes involved in the primary follicular development of chicken. The primary follicles were divided into two groups-small primary follicles (81-150 µm) and developed primary follicles (300-500 µm). Differential expression analysis (fold change > 1.2, p-value < 0.05) revealed a total of 70 differentially expressed proteins (DEPs), of which 38 were upregulated and 32 were downregulated. Gene ontology (GO) enrichment analysis disclosed that DEPs were intricate with cellular protein localization, the establishment of protein localization, and nucleoside phosphate-binding activities. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment pathway indicated the involvement of DEPs in different metabolic pathways such as glycolysis, pyruvate metabolism, galactose metabolism, and fructose and mannose metabolism. The current proteomic analysis suggested suitable markers such as Anxa2, Pdia3, and Capzb, which may serve as a potential role for primary follicle development. The present study provides the first insight into the proteome dynamics of primary follicle development and would play a potential role for further studies in chicken to improve egg productivity.

20.
Theriogenology ; 149: 38-45, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32234649

RESUMO

The presence of serum in embryo culture medium has been implicated for increased embryo's sensitivity to cryopreservation, compromised viability, abnormal embryo and fetal development. Hence, designing a serum free culture system is indispensable. The present study aims to compare the efficiency of the serum and granulosa cells monolayer free commercial culture system (SFCS) with the conventional serum supplemented co-culture system (SSCS) and optimized culture system (OCS). Generally, SFCS is designed explicitly for bovine oocyte maturation and embryo culture (SF-IVM and SF-IVC), and SSCS (based on M199, SS-IVM, and SS-IVC) is utilized for buffalo in vitro embryo production. However, OCS is a newly designed culture system in which oocyte maturation is performed in serum supplemented maturation medium, and the subsequent embryos are co-cultured with granulosa cells in serum free culture medium. To evaluate the effect of serum on buffalo embryo production, buffalo oocytes, and their subsequent embryos were cultured in SSCS, SFCS, and OCS, simultaneously. The percentage of cleaved embryos cultured in SSCS and OCS was approximately 4% higher as compared to SFCS. However, OCS significantly showed the maximum proportion of embryos that developed to the blastocyst stage (7d) and hatched (6d) as compared to the SFCS and SSCS. Additionally, OCS promoted the expression of developmentally important genes (BCL2-L1 and VEGF-A), cell number, and cryo-survival ability of blastocysts in comparison with SSCS. Taken together, OCS is more suitable for the oocyte maturation and culture of buffalo embryos. However, to design the serum free culture system, it is recommended to find suitable serum alternatives for in vitro oocyte maturation.


Assuntos
Búfalos/embriologia , Técnicas de Cultura Embrionária/veterinária , Animais , Blastocisto/fisiologia , Técnicas de Cocultura/veterinária , Criopreservação/veterinária , Meios de Cultura , Meios de Cultura Livres de Soro , Técnicas de Cultura Embrionária/métodos , Embrião de Mamíferos/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células da Granulosa/fisiologia , Técnicas de Maturação in Vitro de Oócitos/métodos , Técnicas de Maturação in Vitro de Oócitos/veterinária
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