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1.
Nature ; 581(7808): 283-287, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32433617

RESUMEN

Traditional metallic alloys are mixtures of elements in which the atoms of minority species tend to be distributed randomly if they are below their solubility limit, or to form secondary phases if they are above it. The concept of multiple-principal-element alloys has recently expanded this view, as these materials are single-phase solid solutions of generally equiatomic mixtures of metallic elements. This group of materials has received much interest owing to their enhanced mechanical properties1-5. They are usually called medium-entropy alloys in ternary systems and high-entropy alloys in quaternary or quinary systems, alluding to their high degree of configurational entropy. However, the question has remained as to how random these solid solutions actually are, with the influence of short-range order being suggested in computational simulations but not seen experimentally6,7. Here we report the observation, using energy-filtered transmission electron microscopy, of structural features attributable to short-range order in the CrCoNi medium-entropy alloy. Increasing amounts of such order give rise to both higher stacking-fault energy and hardness. These findings suggest that the degree of local ordering at the nanometre scale can be tailored through thermomechanical processing, providing a new avenue for tuning the mechanical properties of medium- and high-entropy alloys.

2.
Nature ; 570(7761): 358-362, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31217599

RESUMEN

The ability to manipulate the twisting topology of van der Waals structures offers a new degree of freedom through which to tailor their electrical and optical properties. The twist angle strongly affects the electronic states, excitons and phonons of the twisted structures through interlayer coupling, giving rise to exotic optical, electric and spintronic behaviours1-5. In twisted bilayer graphene, at certain twist angles, long-range periodicity associated with moiré patterns introduces flat electronic bands and highly localized electronic states, resulting in Mott insulating behaviour and superconductivity3,4. Theoretical studies suggest that these twist-induced phenomena are common to layered materials such as transition-metal dichalcogenides and black phosphorus6,7. Twisted van der Waals structures are usually created using a transfer-stacking method, but this method cannot be used for materials with relatively strong interlayer binding. Facile bottom-up growth methods could provide an alternative means to create twisted van der Waals structures. Here we demonstrate that the Eshelby twist, which is associated with a screw dislocation (a chiral topological defect), can drive the formation of such structures on scales ranging from the nanoscale to the mesoscale. In the synthesis, axial screw dislocations are first introduced into nanowires growing along the stacking direction, yielding van der Waals nanostructures with continuous twisting in which the total twist rates are defined by the radii of the nanowires. Further radial growth of those twisted nanowires that are attached to the substrate leads to an increase in elastic energy, as the total twist rate is fixed by the substrate. The stored elastic energy can be reduced by accommodating the fixed twist rate in a series of discrete jumps. This yields mesoscale twisting structures consisting of a helical assembly of nanoplates demarcated by atomically sharp interfaces with a range of twist angles. We further show that the twisting topology can be tailored by controlling the radial size of the structure.

3.
Reprod Biomed Online ; 49(3): 103993, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38901380

RESUMEN

RESEARCH QUESTION: Is acrosin activity related to cumulative live birth rate (CLBR) over 1 year after IVF, intracytoplasmic sperm injection (ICSI) treatment or both? DESIGN: Retrospective monocentric cohort study of 5704 couples who started IVF/ICSI treatments between 2016 and 2021. Acrosin activity was determined by a modified Kennedy method using a commercial kit. Patients were divided into two groups according to their acrosin activity: below 25 µIU/106 spermatozoa; and an acrosin activity 25 µIU/106 spermatozoa or above. Primary outcome was the CLBR, defined as an ongoing pregnancy leading to live birth that had arisen from all embryo transfers carried out within 1 year after the first ovum retrieval. Both conservative and optimistic methods were used for estimating CLBRs. RESULTS: The CLBRs of patients with an acrosin activity below 25 µIU/106 spermatozoa were found to be significantly lower than those of patients with an acrosin activity 25 µIU/106 spermatozoa or above by conservative (48.5% versus 55.4%, P = 0.02) and optimistic (63.7% versus 70.3%, P = 0.047) methods after adjusting for confounders. When acrosin activity was regarded as a continuous variable, significant negative relationships between acrosin activity and CLBR were identified in subgroups: young couples (men and women aged younger than 30 years) and couples from whom no more than 10 eggs were retrieved. CONCLUSION: Low acrosin activity levels were correlated with decreasing CLBRs over 1 year. These findings suggest that acrosin activity can be used as a predictor for CLBRs before starting IVF/ICSI treatment to enhance the effectiveness of counselling.

4.
J Assist Reprod Genet ; 41(1): 3-13, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37878219

RESUMEN

PURPOSE: Recurrent implantation failure (RIF) affects up to 10% of in vitro fertilization (IVF) patients worldwide. However, the pathogenesis of RIF remains unclear. This study was aimed at identifying hub transcription factors (TFs) of RIF in bioinformatics approaches. METHODS: The GSE111974 (mRNA), GSE71332 (miRNA), and GSE103465 (mRNA) datasets were downloaded from the Gene Expression Omnibus database from human endometrial tissue using R version 4.2.1 and used to identify differentially expressed TFs (DETFs), differentially expressed miRNAs, and differentially expressed genes for RIF, respectively. DETFs were subjected to functional enrichment analysis and the protein-protein interaction network analysis using the Search Tool for the Retrieval of Interacting Genes (version 11.5) database. Hub TFs were identified using the cytoHubb plug-in, after which a hub TF-miRNA-mRNA network was constructed using Cytoscape v3.8.2. RESULTS: Fifty-seven DETFs were identified, in which Gene Ontology analysis revealed to be mainly involved in the regulation of transcription. Kyoto Encyclopedia of Genes and Genomes pathway analysis suggested that DETFs were enriched in transcriptional misregulation in cancer, aldosterone synthesis and secretion, AMPK signaling pathway, and cGMP-PKG signaling pathway. EOMES, NKX2-1, and POU5F1 were identified as hub TFs, and a hub TF-miRNA-mRNA regulatory network was constructed using these three hub TFs, four miRNAs, and four genes. CONCLUSION: Collectively, we identified three promising molecular biomarkers for the diagnosis of RIF, which may further be potential therapeutic targets. This study provides novel insights into the molecular mechanisms underlying RIF. However, further experiments are required to verify these results.


Asunto(s)
MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Redes Reguladoras de Genes/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Biología Computacional/métodos
5.
Ann Surg Oncol ; 30(13): 8561-8571, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37718336

RESUMEN

BACKGROUND: The effect of a single tumor marker on the prognosis of gastric cancer patients is not ideal. This study explored a novel prognostic assessment method for gastric cancer (GC) patients using a combination of three important tumor markers (CEA, CA72-4, and CA19-9). METHOD: Data from 1966 GC patients who underwent curative gastrectomy at Sun Yat-Sen University Cancer Center (Guangzhou, China) were included. Hazard ratios (HR) for all factors for overall survival (OS) were analyzed by Cox regression. A nomogram and calibration curve were used to establish the survival prediction model. The prediction accuracy was evaluated with the concordance index (C-index). RESULTS: All patients were divided into four groups (C0-C3) according to the number of elevated tumor markers. The 5-year OS rates of the patients in preoperative groups C0-C3 were 83.8% (81.3-86.4%), 72.8% (68.5-77.4%), 58.9% (50.4-68.9%), and 18.5% (4.0-33.0%), respectively, and those in postoperative groups C0-C3 were 82.1% (79.4-84.8%), 76.1% (72.2-80.3%), 57.6% (48.4-68.5%), and 16.8% (5.1-28.5%), respectively, with significant differences between each C0-C3 subgroup in both preoperative and postoperative cohorts. Multivariate analysis showed that preoperative (HR: 6.001, 95% CI: 3.523-10.221) and postoperative (HR: 8.149, 95% CI: 4.962-13.528) elevated tumor markers were independent risk factors for GC patients. The C-index for the combined use of tumor markers was 0.65-0.66, which was higher than that for using a single tumor marker (0.53-0.56). CONCLUSION: The combined use of tumor markers significantly improved the prognostic value compared with using a single tumor marker. The survival prediction model including the combined tumor markers was accurate and effective.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Gástricas , Humanos , Pronóstico , Neoplasias Gástricas/patología , Antígeno Carcinoembrionario , Estudios Retrospectivos
6.
J Obstet Gynaecol Res ; 49(8): 2093-2101, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37277920

RESUMEN

AIM: Vitamin D3 has been implicated in multiple reproductive events, whereas the effect of its bioactive metabolite 1α, 25 dihydroxyvitamin D3 (1,25(OH) 2 D3 ) on transcriptome profile of the placenta is unclear. The aim of this article is to determine transcriptome-wide profile caused by 1,25(OH) 2 D3 in human placental trophoblast cells. METHODS: We performed RNA sequencing after stimulation of HTR-8/SVneo cells with 0.1, 1, 10, and 100 nM 1,25(OH)2 D3 for 24 h, identified differentially expressed genes by edgeR package (version 3.38.4), and analyzed Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways by webtool Metascape. Also, common genes and specific genes in different concentrations of 1,25(OH) 2 D3 were identified. RESULTS: There were 180, 158, 161, and 174 differentially expressed genes after 0.1, 1, 10, and 100 nM 1,25(OH) 2 D3 stimulation, respectively. KEGG pathway analysis displayed that "lipid and atherosclerosis" were significantly enriched at 0.1 and 1 nM 1,25(OH)2 D3 , while "cytokine-cytokine receptor interaction," "TGF-beta signaling pathway" and "hippo signaling pathway" were significantly enriched in 1, 10, and 100 nM 1,25(OH)2 D3 . CYP24A1 was a significantly expressed common gene. UCP3 was significantly expressed in low concentrations and might affect energy metabolism. TCF24, EIF3CL, ABCD2, EPHA7, CRLF1, and SECTM1 were specific genes at physiological concentration. Similarly, SPDYE1, IQUB, IL18R1, and ZNF713 were considered as specific genes at supraphysiological concentration. CONCLUSIONS: 1,25(OH)2 D3 mainly affected the expression of CYP24A1 gene in HTR-8/SVneo cells. Specific genes accounted for the majority of differentially expressed genes at different concentrations. However, their functions need to be further confirmed.


Asunto(s)
Placenta , Transcriptoma , Femenino , Humanos , Embarazo , Vitamina D3 24-Hidroxilasa/metabolismo , Placenta/metabolismo , Vitamina D , Colecalciferol
7.
Microsc Microanal ; 29(5): 1628-1638, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37584510

RESUMEN

We demonstrate a new focused ion beam sample preparation method for atom probe tomography. The key aspect of the new method is that we use a neon ion beam for the final tip-shaping after conventional annulus milling using gallium ions. This dual-ion approach combines the benefits of the faster milling capability of the higher current gallium ion beam with the chemically inert and higher precision milling capability of the noble gas neon ion beam. Using a titanium-aluminum alloy and a layered aluminum/aluminum-oxide tunnel junction sample as test cases, we show that atom probe tips prepared using the combined gallium and neon ion approach are free from the gallium contamination that typically frustrates composition analysis of these materials due to implantation, diffusion, and embrittlement effects. We propose that by using a focused ion beam from a noble gas species, such as the neon ions demonstrated here, atom probe tomography can be more reliably performed on a larger range of materials than is currently possible using conventional techniques.

8.
Small ; 18(41): e2203310, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36084232

RESUMEN

The rapid advancement of transmission electron microscopy has resulted in revolutions in a variety of fields, including physics, chemistry, and materials science. With single-atom resolution, 3D information of each atom in nanoparticles is revealed, while 4D electron tomography is shown to capture the atomic structural kinetics in metal nanoparticles after phase transformation. Quantitative measurements of physical and chemical properties such as chemical coordination, defects, dislocation, and local strain have been made. However, due to the incompatibility of high dose rate with other ultrathin morphologies, such as nanowires, atomic electron tomography has been primarily limited to quasi-spherical nanoparticles. Herein, the 3D atomic structure of a complex core-shell nanowire composed of an ultrathin Boerdijk-Coxeter-Bernal (BCB) core nanowire and a noble metal thin layer shell deposited on the BCB nanowire surface is discovered. Furthermore, it is demonstrated that a new superthin noble metal layer deposition on an ultrathin BCB nanowire could mitigate electron beam damage using an in situ transmission electron microscope and atomic resolution electron tomography. The colloidal coating method developed for electron tomography can be broadly applied to protect the ultrathin nanomaterials from electron beam damage, benefiting both the advanced material characterizations and enabling fundamental in situ mechanistic studies.


Asunto(s)
Nanopartículas del Metal , Nanocables , Tomografía con Microscopio Electrónico , Electrones , Nanopartículas del Metal/química , Metales/química , Microscopía Electrónica de Transmisión , Nanocables/química
9.
Nat Mater ; 20(4): 468-472, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33020612

RESUMEN

It has been known for decades that the application of pulsed direct current can significantly enhance the formability of metals. However, the detailed mechanisms of this effect have been difficult to separate from simple Joule heating. Here, we study the electroplastic deformation of Ti-Al (7 at.% Al), an alloy that is uniquely suited for uncoupling this behaviour because, contrary to most metals, it has inherently lower ductility at higher temperature. We find that during mechanical deformation, electropulsing enhances cross-slip, producing a wavy dislocation morphology, and enhances twinning, which is similar to what occurs during cryogenic deformation. As a consequence, dislocations are prevented from localizing into planar slip bands that would lead to the early failure of the alloy under tension. Our results demonstrate that this macroscopic electroplastic behaviour originates from defect-level microstructural reconfiguration that cannot be rationalized by simple Joule heating.

10.
Afr J Reprod Health ; 26(5): 107-119, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-37585103

RESUMEN

In recent years, contraceptive medication has been widely used for birth control. It is worth noting that contraceptive medication from botanical source has great potential for clinical use. Yunnan is the province with the most species of plants in China and is known as the "plant kingdom". This study aims to archive herbal remedies traditionally used as antifertility remedies in Dali District, Yunnan Province, P. R. China. The survey was conducted from February 2011 to September 2016 in the population distributed in Dali and the surrounding counties. The data were collected from three groups of practitioners within the study area: therapists using traditional medicines (n = 104), aboriginal families (n = 37), and herbalists in commercial stalls (n = 12), and a total number of 117 plant species were recorded. Among the 117 plant species, 104 of which have been authenticated by a plant taxonomist from the Dali Herbarium. These plants were classified into 98 genera and 54 families, including Leguminosae (12 species), Liliaceae (7 species), Cucurbitaceae, Rosaceae and Rutaceae (5 species, respectively), Malvaceae, Compositae and Euphorbiaceae (4 species, respectively). Our data provides an in-depth delineation of the contraceptive plants used in Dali, which serve as valuable information for the practitioners of traditional Chinese medicine in contraceptive use. In addition, these data also hint that plants from different genus contain contraceptive components, which should be avoided by pregnant women. Future studies are required to identify the active contraceptive components, assess the toxicology, and elucidate the pharmacological mechanism of action.


Asunto(s)
Plantas Medicinales , Embarazo , Femenino , Humanos , Fitoterapia , China , Etnobotánica , Anticonceptivos
11.
BMC Surg ; 20(1): 42, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32122361

RESUMEN

BACKGROUND: We herein report a rare case of an ectopic bronchogenic cyst of the gastric cardia. The initial diagnosis was a gastrointestinal stromal tumor (GIST); however, postoperative pathologic examination confirmed that it was a bronchogenic cyst. CASE PRESENTATION: A 62-year-old woman visited our hospital for abdominal pain. The diagnosis prior to surgery was a GIST. Computed tomography imaging showed that the mass was located in the gastric cardia on the side of the lesser curvature. During the surgical exploration, it was noted that the tactility of the mass was not consistent with a GIST. Thus, we decided to perform local resection of the mass and part of the gastric wall without wedge resection. The pathological examination revealed a bronchogenic cyst. CONCLUSIONS: This case suggests that a bronchogenic cyst should be considered as a differential diagnosis of a GIST. It is also a unusual but necessary situation should be considered when explaining the etiology of a bronchogenic cyst.


Asunto(s)
Quiste Broncogénico/diagnóstico , Tumores del Estroma Gastrointestinal/diagnóstico , Neoplasias Gástricas/diagnóstico , Dolor Abdominal/etiología , Cardias/patología , Diagnóstico Diferencial , Femenino , Tumores del Estroma Gastrointestinal/patología , Humanos , Persona de Mediana Edad , Neoplasias Gástricas/cirugía , Tomografía Computarizada por Rayos X
12.
J Craniofac Surg ; 30(6): 1836-1839, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31449218

RESUMEN

OBJECTIVES: To explore the changes of brain susceptibility of different sides and genders in healthy young adults using quantitative susceptibility mapping (QSM). METHODS: Totally 42 healthy young right-handed adults underwent conventional brain magnetic resonance imaging and QSM scans, and the susceptibility maps were obtained by image post-processing software. Then the regions-of-interest (ROI) of bilateral frontal gray matter (FGM), frontal white matter (FWM), caudate (CA), globus pallidus (GP), putamen (PU), thalamus (TH), substantia nigra (SN), red nucleus (RN), dentate nucleus (DN), pons (PO), and corpus callosum (CC) were manually drawn to obtain magnetic susceptibility on the susceptibility maps. The magnetic susceptibility of each ROI was compared between 2 sides and genders by Wilcoxon rank sum test. RESULTS: Magnetic susceptibility of bilateral ROI was the highest in GP, followed by SN, and the lowest in FWM. No statistically significant difference was found in susceptibility of bilateral FGM, FWM, CA, GP, PU, TH, SN, RN, DN, PO, or CC. Magnetic susceptibility in CA significantly different genders. CONCLUSION: Brain magnetic susceptibility measured by QSM can be used to quantitatively assess brain iron concentrations.


Asunto(s)
Encéfalo/diagnóstico por imagen , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Masculino , Programas Informáticos , Adulto Joven
13.
J Craniofac Surg ; 30(7): e674-e677, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31574790

RESUMEN

INTRODUCTION: Von Hippel-Lindau (VHL) syndrome is a group of rare autosomal dominant hereditary diseases that involve multiple organs. Due to its high recurrence rate and complex and diverse clinical manifestations, VHL is prone to being either misdiagnosed or missed entirely. Therefore, patients with VHL syndrome have a poor prognosis. CLINICAL FEATURES: This study reports the details of 2 patients, a 55-year-old male and a 37-year-old female, who were diagnosed as having VHL syndrome with a positive family history. The male patient presented with upper abdominal discomfort 2 years prior to the current study, and was diagnosed in another hospital as having a space-occupying lesion at the head of the pancreas. After undergoing hemangioblastoma resection of the right cerebellar hemisphere 1 month ago, he was admitted to the hospital for recent aggravation of upper abdominal discomfort to receive further diagnosis and treatment. The female patient previously underwent right ovarian cystectomy and T5-T6 intramedullary hemangioblastoma resection. She was diagnosed at another hospital as having pancreatic cancer, and was admitted to the hospital for recent aggravation of upper abdominal discomfort to receive further diagnosis and treatment. CONCLUSION: The diagnosis and treatment of VHL syndrome is currently relatively difficult. It poses a substantial threat to patients and their families. The early and timely diagnosis and treatment of VHL syndrome can improve patients' prognosis and rates of survival.


Asunto(s)
Errores Diagnósticos , Enfermedad de von Hippel-Lindau/diagnóstico por imagen , Adulto , Femenino , Hemangioblastoma/cirugía , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico , Pronóstico
14.
Nano Lett ; 18(3): 1819-1825, 2018 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-29462550

RESUMEN

Engineering the structure of materials endows them with novel physical properties across a wide range of length scales. With high in-plane stiffness and strength, but low flexural rigidity, two-dimensional (2D) materials are excellent building blocks for nanostructure engineering. They can be easily bent and folded to build three-dimensional (3D) architectures. Taking advantage of the large lattice mismatch between the constituents, we demonstrate a 3D heterogeneous architecture combining a basal Bi2Se3 nanoplate and wavelike Bi2Te3 edges buckling up and down forming periodic ripples. Unlike 2D heterostructures directly grown on substrates, the solution-based synthesis allows the heterostructures to be free from substrate influence during the formation process. The balance between bending and in-plane strain energies gives rise to controllable rippling of the material. Our experimental results show clear evidence that the wavelengths and amplitudes of the ripples are dependent on both the widths and thicknesses of the rippled material, matching well with continuum mechanics analysis. The rippled Bi2Se3/Bi2Te3 heterojunction broadens the horizon for the application of 2D materials heterojunction and the design and fabrication of 3D architectures based on them, which could provide a platform to enable nanoscale structure generation and associated photonic/electronic properties manipulation for optoelectronic and electromechanic applications.

15.
Biochem Biophys Res Commun ; 498(4): 1002-1008, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29550489

RESUMEN

Long non-coding RNA (lncRNA) is an important member of non-coding RNA family and emerging evidence has indicated that it plays a pivotal role in many physiological and pathological processes. The lncRNA X inactive specific transcript (XIST) is a potential tumour suppressor in some types of cancers. However, the expression and function of XIST in breast cancer remain largely unclear. The objective of this study was to evaluate the expression and biological role of XIST in breast cancer. The results showed that XIST was significantly down-regulated in breast cancer tissues and cell lines. Further functional analysis indicated that overexpression of XIST remarkably inhibited breast cancer cell growth, migration, and invasion. The results of luciferase reporter assays verified that miR-155 was a direct target of XIST in breast cancer. Moreover, caudal-type homeobox 1 (CDX1) was identified as a direct target of miR-155 and miR-155/CDX1 rescued the effects of XIST in breast cancer cells. Taken together, our results suggest that XIST is down-regulated in breast cancer and suppresses breast cancer cell growth, migration, and invasion via the miR-155/CDX1 axis.


Asunto(s)
Neoplasias de la Mama/genética , Proteínas de Homeodominio/fisiología , MicroARNs/fisiología , ARN Largo no Codificante/antagonistas & inhibidores , ARN Largo no Codificante/fisiología , Neoplasias de la Mama/química , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , ARN Largo no Codificante/análisis , Células Tumorales Cultivadas
17.
J Assist Reprod Genet ; 35(5): 809-816, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29502189

RESUMEN

PURPOSE: The aim of this study was to create a predictive model for high-quality blastocyst progression based on the traditional morphology parameters of embryos. METHODS: A total of 1564 embryos from 234 women underwent conventional in vitro fertilization and were involved in the present study. High-quality blastocysts were defined as having a grade of at least 3BB, and all embryos were divided based on the development of high-quality blastocysts (group HQ) or the failure to develop high-quality blastocysts (group NHQ). A retrospective analysis of day-3 embryo parameters, focused on blastomere number, fragmentation, the presence of a vacuole, symmetry, and the presence of multinucleated blastomeres was conducted. RESULTS: All parameters were related to high-quality blastocysts (p < 0001) in t tests, chi-square tests, or Fisher tests. The individual scores for all parameters were determined according to their distributions and corresponding rates of forming high-quality blastocysts. Parameters are indicated by s_bn (blastomere number), s_f (fragmentation), s_pv (presence of a vacuole), s_s (symmetry), and s_MNB (multinucleated blastomeres). Subsequently, univariate and multivariate logistic regression analyses were conducted to explore their relationship. In the multivariate logistic regression analysis, a predictive model was constructed, and a parameter Hc was created based on the s_bn, s_f, and s_s parameters and their corresponding odds ratios. The value of Hc in group HQ was significantly higher than that in group NHQ. A receiver operating characteristic curve was used to test the effectiveness of the model. An area under the curve of 0.790, with a 95% confidence interval of 0.766-0.813, was calculated. A dataset was used to validate the predictive utility of the model. Moreover, another dataset was used to ensure that the model can be applied to predict the implantation of day-3 embryos. CONCLUSIONS: A predictive model for high-quality blastocysts was created based on blastomere number, fragmentation, and symmetry. This model provides novel information on the selection of potential embryos.


Asunto(s)
Blastocisto/fisiología , Blastómeros/citología , Fertilización In Vitro/métodos , Modelos Biológicos , Adulto , Blastocisto/citología , Técnicas de Cultivo de Embriones/métodos , Implantación del Embrión , Femenino , Humanos , Modelos Logísticos , Masculino , Edad Materna , Embarazo , Índice de Embarazo , Curva ROC
18.
Reprod Biomed Online ; 28(5): 644-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24631383

RESUMEN

As an important methyltransferase, DNMT1 plays a key role in DNA methylation that is essential for normal spermatogenesis, which suggests that it may be involved in male infertility with spermatogenesis impairment. To explore the relationship between DNMT1 and spermatogenesis impairment, polymorphic distributions of single-nucleotide polymorphisms (SNP) rs16999593, rs2228612 and rs2228611 in DNMT1 were investigated in 342 infertile patients with idiopathic azoospermia or oligospermia and 232 fertile controls in a Chinese population. As a result, no significant differences in allele and genotype frequencies of the three SNP between total patients and controls were observed. However, after stratifying the patients, significant differences in allele and genotype frequencies were detected between oligospermia subgroup and control group. The frequencies of rs16999593 allele A (83.6% versus 77.6%, P=0.033) and genotype AA (69.2% versus 59.0%, P=0.037) and SNP rs2228611 genotype AA (18.4% versus 9.9%, P=0.016) in patients with oligospermia were significantly higher than those in control group. These findings suggest that the polymorphism in DNMT1 might be associated with oligospermia and could modify the susceptibility of oligospermia.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/genética , Predisposición Genética a la Enfermedad , Oligospermia/genética , Polimorfismo de Nucleótido Simple , Adulto , Estudios de Casos y Controles , ADN (Citosina-5-)-Metiltransferasa 1 , Frecuencia de los Genes , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad
19.
J Assist Reprod Genet ; 31(10): 1391-5, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25106941

RESUMEN

PURPOSE: This study aims to explore possible associations between polymorphisms of common SNP rs1136410 and rS1805405 in PARP1 gene and male infertility with spermatogenesis impairment. METHODS: The polymorphic distributions of SNP rs1136410 and rS1805405 were investigated by polymerase chain reaction and restriction fragment length polymorphism analysis in a Chinese cohort including 371 infertile patients with idiopathic azoospermia or oligospermia and 231 controls. RESULTS: Significant differences in the frequencies of allele and genotype of SNP rs1136410 were observed between patients with oligospermia and controls. The allele C (46.3 % vs. 36.4 %, P = 0.003) and genotype CC (22.6 % vs. 13.4 %, P = 0.014) significantly increased, whereas genotype TT (30 % vs. 40.7 %, P = 0.021) significantly decreased in patients with oligospermia compared with controls at this SNP locus. CONCLUSIONS: These results indicated that genotype CC of SNP rs1136410 may increase the risk of oligosoermia and genotype TT of rs1136410 may have some protective effect from oligospermia, suggesting that the polymorphism of SNP rs1136410 in PARP1 gene may modify the susceptibility to male infertility with oligospermia.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Infertilidad Masculina/genética , Oligospermia/genética , Poli(ADP-Ribosa) Polimerasas/genética , Polimorfismo de Nucleótido Simple/genética , Alelos , Pueblo Asiatico/genética , Azoospermia/genética , Frecuencia de los Genes/genética , Genotipo , Humanos , Masculino , Poli(ADP-Ribosa) Polimerasa-1
20.
Transl Cancer Res ; 13(4): 2026-2042, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38737700

RESUMEN

Background and Objective: Lysyl oxidase-like protein 4 (LOXL4) is a secreted copper-dependent amine oxidase involved in the assembly and maintenance of extracellular matrix (ECM), playing a critical role in ECM formation and repair. Tumor-stroma interactions and ECM dysregulation are closely associated with the mechanisms underlying tumor initiation and progression. LOXL4 is the latest identified member of the lysyl oxidase (LOX) protein family. Currently, there is limited and controversial research on the role of LOXL4 in human malignancies. Its specific regulatory pathways, mechanisms, and roles in the occurrence, development, and treatment of malignancies remain incompletely understood. This article aims to illustrate the primary protein structure and the function of LOXL4 protein, and the relationship between LOXL4 protein and the occurrence and development of human malignant tumors to provide a reference for further clinical research. Methods: We searched the English literature on LOXL4 in the occurrence and development of various malignant tumors in PubMed and Web of Science. The search keywords include "cancer" "LOXL4" "malignant tumor" "tumorigenesis and development", etc. Key Content and Findings: LOXL4 is up-regulated in human gastric cancer, breast cancer, ovarian cancer, head and neck squamous cell carcinoma, esophageal carcinoma and colorectal cancer, but down-regulated in human bladder cancer and lung cancer and inhibits tumor growth. There are two conflicting reports of both upregulation and downregulation in hepatocellular carcinoma, suggesting that LOXL4 has a bidirectional effect of promoting or inhibiting cancer in different types of human malignant tumors. We further explore the application prospect of LOXL4 protein in the study of malignant tumors, laying a theoretical foundation for the clinical diagnosis, treatment and screening of prognostic markers of malignant tumors. Conclusions: LOXL4 exerts a bidirectional regulatory role, either inhibiting or promoting tumors depending on the type of cancer. We still need more research to further confirm the molecular mechanism of LOXL4 in cancer progression.

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