Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nano Lett ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949784

RESUMO

The simultaneous detection of the orbital angular momentum (OAM) and wavelength offers new opportunities for optical multiplexing. However, because of the dispersion of lens functions for Fourier transformation, the mode conversions at distinct wavelengths cannot be achieved in the same plane. Here we propose an ultracompact achromatic complementary metal oxide semiconductor (CMOS)-integrated OAM mode detector. Specifically, a spatial multiplexed scheme, randomly interleaving the phase distributions for distributing the superposed OAM modes into preset positions at distinct wavelengths, is presented. In addition, such a nanoprinted achromatic OAM detector featuring a microscale size and a short focal length can be integrated onto a CMOS chip. Consequently, the four-bit incident light beams at three discrete wavelengths (633, 532, and 488 nm) can be distinguished with a high degree of accuracy evaluated by the average standardized Euclidean distance of ∼0.75 between the analytical and target results. Our results showcase a miniaturized platform for achieving high-capacity information processing.

2.
Environ Sci Technol ; 58(24): 10415-10444, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38848315

RESUMO

Persulfate (PS)-based advanced oxidation processes (AOPs) for pollutant removal have attracted extensive interest, but some controversies about the identification of reactive species were usually observed. This critical review aims to comprehensively introduce basic concepts and rectify cognitive biases and appeals to pay more attention to experimental details in PS-AOPs, so as to accurately explore reaction mechanisms. The review scientifically summarizes the character, generation, and identification of different reactive species. It then highlights the complexities about the analysis of electron paramagnetic resonance, the uncertainties about the use of probes and scavengers, and the necessities about the determination of scavenger concentration. The importance of the choice of buffer solution, operating mode, terminator, and filter membrane is also emphasized. Finally, we discuss current challenges and future perspectives to alleviate the misinterpretations toward reactive species and reaction mechanisms in PS-AOPs.


Assuntos
Oxirredução , Sulfatos/química
3.
Environ Sci Technol ; 58(17): 7672-7682, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38639327

RESUMO

The development of efficient technologies for the synergistic catalytic elimination of NOx and chlorinated volatile organic compounds (CVOCs) remains challenging. Chlorine species from CVOCs are prone to catalyst poisoning, which increases the degradation temperature of CVOCs and fails to balance the selective catalytic reduction of NOx with the NH3 (NH3-SCR) performance. Herein, synergistic catalytic elimination of NOx and chlorobenzene has been originally demonstrated by using phosphotungstic acid (HPW) as a dechlorination agent to collaborate with CeO2. The conversion of chlorobenzene was over 80% at 270 °C, and the NOx conversion and N2 selectivity reached over 95% at 270-420 °C. HPW not only allowed chlorine species to leave as inorganic chlorine but also enhanced the BroÌ·nsted acidity of CeO2. The NH4+ produced in the NH3-SCR process can effectively promote the dechlorination of chlorobenzene at low temperatures. HPW remained structurally stable in the synergistic reaction, resulting in good water resistance and long-term stability. This work provides a cheaper and more environmentally friendly strategy to address chlorine poisoning in the synergistic reaction and offers new guidance for multipollutant control.


Assuntos
Clorobenzenos , Catálise , Clorobenzenos/química , Compostos Orgânicos Voláteis/química , Cloro/química , Cério/química , Halogenação
4.
Langmuir ; 39(21): 7434-7443, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37200447

RESUMO

Mn-based catalysts are promising for selective catalytic reduction (SCR) of NOx with NH3 at low temperatures due to their excellent redox capacity. However, the N2 selectivity of Mn-based catalysts is an urgent problem for practical application owing to excessive oxidizability. To solve this issue, we report a Mn-based catalyst using amorphous ZrTiOx as the support (Mn/ZrTi-A) with both excellent low-temperature NOx conversion and N2 selectivity. It is found that the amorphous structure of ZrTiOx modulates the metal-support interaction for anchoring the highly dispersed active MnOx species and constructs a uniquely bridged Mn3+ bonded with the support through oxygen linked to Ti4+ and Zr4+, respectively, which regulates the optimal oxidizability of the MnOx species. As a result, Mn/ZrTi-A is not conducive to the formation of ammonium nitrate that readily decomposes to N2O, thus further increasing N2 selectivity. This work investigates the role of an amorphous support in promoting the N2 selectivity of a manganese-based catalyst and sheds light on the design of efficient low-temperature deNOx catalysts.

5.
Langmuir ; 39(25): 8889-8899, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37314863

RESUMO

Unraveling the dynamics of the active sites upon CeO2-based catalysts in selective catalytic reduction of nitrogen oxides by ammonia (NH3-SCR) is challenging. In this work, we prepared tungsten-acidified and sulfated CeO2 catalysts and used operando spectroscopy to reveal the dynamics of acid sites and redox sites on catalysts during NH3-SCR reaction. We found that both Lewis and Brønsted acid sites are needed to participate in the catalytic reaction. Notably, Brønsted acid sites are the main active sites after a tungsten-acidified or sulfated treatment, and the change of Brønsted acid sites significantly affects the NOx removal. Moreover, acid functionalization promotes the cerium species cycle between Ce4+ and Ce3+ for the NOx reduction. This work is critical to deeply understanding the natural properties of active sites, and it also provides new insights into the mechanism for NH3-SCR over CeO2-based catalysts.

6.
Environ Sci Technol ; 57(38): 14472-14481, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37695840

RESUMO

Catalyst deactivation caused by alkali metal poisoning has long been a key bottleneck in the application of selective catalytic reduction of NOx with NH3 (NH3-SCR), limiting the service life of the catalyst and increasing the cost of environmental protection. Despite great efforts, continuous accumulation of alkali metal deposition makes the resistance capacity of 2 wt % K2O difficult to enhance via merely loading acid sites on the surface, resulting in rapid deactivation and frequent replacement of the NH3-SCR catalyst. To further improve the resistance of alkali metals, encapsulating alkali metals into the bulk phase could be a promising strategy. The bottleneck of 2 wt % K2O tolerance has been solved by virtue of ultrahigh potassium storage capacity in the amorphous FePO4 bulk phase. Amorphous FePO4 as a support of the NH3-SCR catalyst exhibited a self-adaptive alkali-tolerance mechanism, where potassium ions spontaneously migrated into the bulk phase of amorphous FePO4 and were anchored by PO43- with the generation of Fe2O3 at the NH3-SCR reaction temperature. This ingenious potassium storage mechanism could boost the K2O resistance capacity to 6 wt % while maintaining approximately 81% NOx conversion. Besides, amorphous FePO4 also exhibited excellent resistance to individual and coexistence of alkali (K2O and Na2O), alkali earth (CaO), and heavy metals (PbO and CdO), providing long durability for CePO4/FePO4 catalysts in flue gas with multipollutants. The cheap and accessible amorphous FePO4 paves the way for the development and implementation of poisoning-resistant NOx abatement.


Assuntos
Álcalis , Potássio , Catálise , Temperatura
7.
Environ Sci Technol ; 57(4): 1797-1806, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36637390

RESUMO

Low-temperature catalytic degradation of volatile organic compounds (VOCs) by enhancing the activity of non-precious metal catalysts has always been the focus of attention. The mineralization of aromatic VOCs requires the participation of a large number of oxygen atoms, so the activation of oxygen species is crucial in the degradation reaction. Herein, we originally adjust the Ce-O bond strength in CeZr oxide catalysts by cobalt doping to promote the activation of oxygen species, thus improving the toluene degradation performance while maintaining high stability. Subsequent characterizations and theoretical calculations demonstrate that the weakening of the Ce-O bond strength increases the oxygen vacancy content, promotes the activation of oxygen species, and enhances the redox ability of the catalysts. This strategy also promotes the activation of toluene and accelerates the depletion of intermediate species. This study will contribute a strategy to enhance the activation ability of oxygen species in non-noble metal oxide catalysts, thereby enhancing the degradation performance of VOCs.


Assuntos
Óxidos , Tolueno , Óxidos/química , Tolueno/química , Oxirredução , Catálise , Oxigênio
8.
Environ Sci Technol ; 57(50): 21470-21482, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38050842

RESUMO

NOx and CH3SH as two typical air pollutants widely coexist in various energy and industrial processes; hence, it is urgent to develop highly efficient catalysts to synergistically eliminate NOx and CH3SH. However, the catalytic system for synergistically eliminating NOx and CH3SH is seldom investigated to date. Meanwhile, the deactivation effects of CH3SH on catalysts and the formation mechanism of toxic byproducts emitted from the synergistic catalytic elimination reaction are still vague. Herein, selective synergistic catalytic elimination (SSCE) of NOx and CH3SH via engineering deep oxidation sites over Cu-modified Nb-Fe composite oxides supported on TiO2 catalyst against toxic CO and HCN byproducts formation has been originally demonstrated. Various spectroscopic and microscopic characterizations demonstrate that the sufficient chemisorbed oxygen species induced by the persistent electron transfer from Nb-Fe composite oxides to copper oxides can deeply oxidize HCOOH to CO2 for avoiding highly toxic byproducts formation. This work is of significance in designing superior catalysts employed in more complex working conditions and sheds light on the progress in the SSCE of NOx and sulfur-containing volatile organic compounds.


Assuntos
Poluentes Atmosféricos , Óxidos , Oxirredução , Óxidos/análise , Óxidos/química , Oxigênio , Transporte de Elétrons , Catálise , Amônia/química
9.
Dig Dis Sci ; 68(1): 128-137, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35590046

RESUMO

BACKGROUND: Radioresistance is a major obstacle for clinical treatment of gastric cancer (GC). has_circ_0003506 (circ_0003506) was reported as an oncogenic factor in GC, but its effect on radioresistant GC is unclear. AIMS: This study aimed to explore the role of circ_0003506 in radioresistance and regulatory mechanism. METHODS: The expression detection was performed by real-time polymerase chain reaction. Cell survival was analyzed by colony formation assay. Cell proliferation was measured by Cell Counting Kit-8 assay and colony formation assay. Cell migration and invasion were examined using transwell assay. Cell apoptosis was assessed by flow cytometry. The target binding was confirmed via dual-luciferase reporter assay. The protein level was determined through western blot. Animal assay was performed for the functional exploration of circ_0003506 on radiosensitivity in vivo. RESULTS: Circ_0003506 was upregulated in radioresistant GC cells. Downregulation of circ_0003506 inhibited radioresistance to repress proliferation, migration and invasion but increase apoptosis in radioresistant GC cells. Circ_0003506 was a sponge of miR-1256. The effects of si-circ_0003506 on radioresistant GC cells were reverted by miR-1256 inhibitor. MiR-1256 suppressed tumor progression in radioresistant GC cells by downregulating bone morphogenetic protein type 2 receptor. Circ_0003506 regulated the level of bone morphogenetic protein type 2 receptor by targeting miR-1256. Downregulating circ_0003506 increased radiosensitivity of GC in vivo via regulating miR-1256 and bone morphogenetic protein type 2 receptor. CONCLUSION: Knockdown of circ_0003506 suppressed radioresistance in GC through the regulation of miR-1256/bone morphogenetic protein type 2 receptor axis. Circ_0003506 might be a therapeutic target in radiotherapy of GC.


Assuntos
MicroRNAs , Neoplasias Gástricas , Animais , Neoplasias Gástricas/genética , Neoplasias Gástricas/radioterapia , Ciclo Celular , Proliferação de Células , Apoptose , Movimento Celular , MicroRNAs/genética , Linhagem Celular Tumoral
10.
Ann Hum Genet ; 86(5): 257-267, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35582845

RESUMO

One of the critical issues in genetic association studies is to evaluate the risk of a disease associated with gene-gene or gene-environment interactions. The commonly employed procedures are derived by assigning a particular set of scores to genotypes. However, the underlying genetic models of inheritance are rarely known in practice. Misspecifying a genetic model may result in power loss. By using some potential genetic variables to separate the genotype coding and genetic model parameter, we construct a model-embedded score test (MEST). Our test is free of assumption of gene-environment independence and allows for covariates in the model. An effective sequential optimization algorithm is developed. Extensive simulations show the proposed MEST is robust and powerful in most of scenarios. Finally, we apply the proposed method to rheumatoid arthritis data from the Genetic Analysis Workshop 16 to further investigate the potential interaction effects.


Assuntos
Interação Gene-Ambiente , Modelos Genéticos , Estudos de Associação Genética , Genótipo , Humanos , Incerteza
11.
Stat Med ; 40(17): 3915-3936, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-33906263

RESUMO

Heterogeneity is a hallmark of many complex diseases. There are multiple ways of defining heterogeneity, among which the heterogeneity in genetic regulations, for example, gene expressions (GEs) by copy number variations (CNVs), and methylation, has been suggested but little investigated. Heterogeneity in genetic regulations can be linked with disease severity, progression, and other traits and is biologically important. However, the analysis can be very challenging with the high dimensionality of both sides of regulation as well as sparse and weak signals. In this article, we consider the scenario where subjects form unknown subgroups, and each subgroup has unique genetic regulation relationships. Further, such heterogeneity is "guided" by a known biomarker. We develop a multivariate sparse fusion (MSF) approach, which innovatively applies the penalized fusion technique to simultaneously determine the number and structure of subgroups and regulation relationships within each subgroup. An effective computational algorithm is developed, and extensive simulations are conducted. The analysis of heterogeneity in the GE-CNV regulations in melanoma and GE-methylation regulations in stomach cancer using the TCGA data leads to interesting findings.


Assuntos
Variações do Número de Cópias de DNA , Melanoma , Algoritmos , Expressão Gênica , Regulação da Expressão Gênica , Humanos , Melanoma/genética
12.
Gen Physiol Biophys ; 40(2): 103-114, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33880997

RESUMO

Circular RNAs (circRNAs) play crucial roles in multiple cancers, including hepatocellular carcinoma (HCC). However, the effects and molecular mechanisms of circ_LRIG3 in HCC remain barely unknown. qRT-PCR assay was employed to detect the levels of circ_LRIG3, LRIG3, miR-449a and ring finger protein 38 (RNF38). RNase R assay and Actinomycin D assay were performed to analyze the characteristics of circ_LRIG3. Colony formation assay and MTT assay were used to evaluate cell proliferation. Flow cytometry analysis and transwell assay were adopted for cell apoptosis and metastasis, respectively. Western blot assay was carried out for the protein levels of Ki67, Snail, E-cadherin, RNF38, Smad2/3 and p-Smad2/3. Murine xenograft model assay was used to explore the role of circ_LRIG3 in vivo. circ_LRIG3 expression was upregulated in HCC tissues and cells. Knockdown of circ_LRIG3 suppressed proliferation, migration and invasion and facilitated cell apoptosis in HCC cells in vitro and blocked tumor growth of HCC in vivo. RNF38 overexpression reversed the effects of circ_LRIG3 knockdown on the malignant behaviors of HCC cells. Moreover, circ_LRIG3 could sponge miR-449a to positively modulate RNF38 expression in HCC cells. circ_LRIG3 knockdown inhibited the progression of HCC cells by sponging miR-449a. In addition, circ_LRIG3 silencing might inhibit the Smad2/3 pathway. circ_LRIG3 facilitated HCC progression by modulation of miR-449a/LRIG3 axis, which might provide a novel method for HCC therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Animais , Carcinoma Hepatocelular/genética , Proliferação de Células/genética , Neoplasias Hepáticas/genética , Camundongos , MicroRNAs/genética , RNA Circular
13.
Opt Express ; 28(9): 13019-13031, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32403784

RESUMO

Vertical-cavity surface-emitting lasers (VCSELs) are the predominant technology for high-speed short-range interconnects in data centers. Most short-range interconnects rely on GaAs-based multi-mode VCSELs and multi-mode fiber links operating at 850 nm. Recently, GaAs-based high-speed single-mode VCSELs at wavelengths > 1 µm have been demonstrated, which increases the interconnect reach using a single-mode fiber while maintaining low energy dissipation. If a suitable platform for passive wavelength- and space-multiplexing were developed in this wavelength range, this single-mode technology could deliver the multi-Tb/s interconnect capacity that will be required in future data centers. In this work, we show the first passive Si3N4 platform in the 1-µm band (1030-1075 nm) with an equivalent loss < 0.3 dB/cm, which is compatible with the system requirements of high-capacity interconnects. The waveguide structure is optimized to achieve simultaneously single-mode operation and low bending radius, and we demonstrate a wide range of high-performance building blocks, including arrayed waveguide gratings, Mach-Zehnder interferometers, splitters and low-loss fiber interfaces. This technology could be instrumental in scaling up the capacity and reducing the footprint of VCSEL-based optical interconnects and, thanks to the broad transparency in the near-infrared and compatibility with the Yb fiber amplifier window, enabling new applications in other domains as optical microscopy and nonlinear optics.

14.
J Clin Lab Anal ; 34(7): e23288, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32185823

RESUMO

BACKGROUND: Terminal duplication on chromosome 15q is a rare chromosomal variation. Affected individuals show similar features such as growth dysplasia or the development of frontal bossing, body deformities, facial abnormalities, and genitourinary or cardiovascular disorders. However, it is not yet clear whether such 15q repeats lead to identifiable patterns of clinical abnormalities. Therefore, the purpose of this study was to analyze the prenatal diagnostic results and clinical manifestations of a fetus with 15q duplication and to summarize the literature. METHODS: The case was a fetus at 28 weeks of gestation. The risk of Down syndrome from second-trimester screening was 1/140. Prenatal ultrasound and amniocentesis were performed, and chromosomal microarray analysis (CMA) was used for genetic analysis. RESULTS: The fetus had abnormal clinical features, including intracardiac echogenic focus in the left ventricle, an aberrant right subclavian artery, and growth delay. The fetal chromosomal karyotype was 46,XX,15q?,12q?,21pstk+, and CMA revealed a 10.163 Mb duplication at 15q24.3-q25.3. The couple chose to terminate the pregnancy after careful consideration. CONCLUSIONS: The combination and rational application of cytogenetics technology and molecular genetics technology such as CMA will open up the field of clinical application and provide useful genetic counseling for parents of fetuses carrying such chromosomal duplications.


Assuntos
Cromossomos Humanos Par 15 , Diagnóstico Pré-Natal/métodos , Tetrassomia/genética , Amniocentese/métodos , Anormalidades Cardiovasculares/diagnóstico por imagem , Anormalidades Cardiovasculares/genética , Análise Citogenética , Feminino , Humanos , Análise em Microsséries , Gravidez , Segundo Trimestre da Gravidez , Artéria Subclávia/anormalidades , Artéria Subclávia/diagnóstico por imagem , Ultrassonografia Pré-Natal
15.
Cytogenet Genome Res ; 157(4): 220-226, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30939474

RESUMO

Trisomy 18p is a rarely observed chromosomal aberration. Only 31 cases have previously been described in the literature. Trisomy 18p is associated with mild to moderate phenotypic anomalies and intellectual disability. Here, we report on a pregnant woman in whom noninvasive prenatal testing indicated a high risk of fetal trisomy 18. Prenatal diagnosis and karyotyping of the parents were performed and demonstrated that both the mother and the fetus had a derivative chromosome 15 with a segment of unknown origin. Chromosomal microarray analysis and FISH revealed a 14.9-Mb duplication of 18p and detected 3 centromeres of chromosome 18. To our knowledge, this is the first study reporting trisomy 18p due to an unbalanced translocation of 18p onto chromosome 15q showing 2-generation transmission. The results suggest that trisomy 18p can be considered a euchromatic variant.


Assuntos
Cromossomos Humanos Par 15/genética , Deficiência Intelectual/genética , Diagnóstico Pré-Natal/métodos , Trissomia/genética , Cromossomos Humanos Par 18/genética , Feminino , Humanos , Hibridização in Situ Fluorescente , Análise de Sequência com Séries de Oligonucleotídeos , Gravidez , Translocação Genética , Adulto Jovem
16.
Biometrics ; 75(2): 392-403, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30648746

RESUMO

In this article, we introduce the concept of model confidence bounds (MCB) for variable selection in the context of nested models. Similarly to the endpoints in the familiar confidence interval for parameter estimation, the MCB identifies two nested models (upper and lower confidence bound models) containing the true model at a given level of confidence. Instead of trusting a single selected model obtained from a given model selection method, the MCB proposes a group of nested models as candidates and the MCB's width and composition enable the practitioner to assess the overall model selection uncertainty. A new graphical tool-the model uncertainty curve (MUC)-is introduced to visualize the variability of model selection and to compare different model selection procedures. The MCB methodology is implemented by a fast bootstrap algorithm that is shown to yield the correct asymptotic coverage under rather general conditions. Our Monte Carlo simulations and real data examples confirm the validity and illustrate the advantages of the proposed method.


Assuntos
Intervalos de Confiança , Modelos Estatísticos , Algoritmos , Interpretação Estatística de Dados , Humanos , Métodos , Método de Monte Carlo , Incerteza
17.
J Clin Lab Anal ; 33(3): e22700, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30390321

RESUMO

BACKGROUND: Nonobstructive azoospermia (NOA) is one of the most severe forms of male infertility because of impaired spermatogenesis with the absence of spermatozoa in the ejaculate. The causes of this disease can be partly attributed to genetic factors. Some common structural variants and single nucleotide polymorphisms (SNPs) were reported to be associated with NOA. However, the underlying etiology and genetic mechanism(s) remain largely unclear. The aim of this study was to investigate the associated mutations of spermatogenic genes in Chinese infertile men with NOA. METHODS: The entire coding region of 25 genes associated with spermatogenesis was sequenced from 200 infertile men with NOA. Screening was carried out using the targeted exome sequencing to identify genetic variations and SNPs of the entire coding region of these genes. RESULTS: After the targeted exome sequencing data were filtered through several currently existing variation databases, a series of variations were found. In this paper, we report one novel stopgain variation c.G992A (p.W331X) in the exon 4 of TACR3 gene. The variant was heterozygous and categorized as pathogenic. CONCLUSION: In conclusion, our study revealed a novel stopgain mutation c.G992A (p.W331X) in TACR3 which expanded the mutation spectrum of TACR3 in Chinese NOA infertile men and advanced our understanding of the genetic susceptibility to NOA.


Assuntos
Azoospermia/genética , Análise Mutacional de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mutação/genética , Receptores da Neurocinina-3/genética , Adulto , Povo Asiático/genética , Estudos de Coortes , Humanos , Masculino
18.
Clin Lab ; 64(10): 1731-1738, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30336530

RESUMO

BACKGROUND: Non-obstructive azoospermia (NOA) is an important factor leading to male infertility and the genetic mechanism is not yet clear. It requires investigation to reveal its occurrence based on sequencing technology from the genetic level. Our previous genome wide association study (GWAS) using targeted high-throughput sequencing technology has identified suspected genetic variants including rs162036, rs161870, rs1677016R and rs1106042R associated with non-obstructive azoospermia (data not published). METHODS: To further investigate the linkage between the four SNPs and the occurrence of NOA, 121 NOA patients and 256 controls were included. SNPs were detected by ligase detection reaction- polymerase chain reaction (LDRPCR). Association study between SNPs and NOA was analyzed. RESULTS: As a result, we found no significant difference in all four alleles and genotypes frequencies in the SNPs between patients and controls (rs161870 p = 0.291; rs1677016R p = 0.264; rs161870 p = 0.291; rs1106042R p = 0.329). CONCLUSIONS: The four SNPs are not shown to be significantly related with NOA. Therefore, the underlying potential genetic markers to Northeast Chinese Han population remain unclear and need to be further clarified.


Assuntos
Proteínas Argonautas/genética , Azoospermia/genética , Ferredoxina-NADP Redutase/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único , Fatores Associados à Proteína de Ligação a TATA/genética , Fator de Transcrição TFIID/genética , Adulto , Povo Asiático/genética , Azoospermia/etnologia , China , Frequência do Gene , Predisposição Genética para Doença/etnologia , Genótipo , Haplótipos , Humanos , Infertilidade Masculina/etnologia , Infertilidade Masculina/genética , Masculino
19.
Med Sci Monit ; 24: 4162-4168, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29911662

RESUMO

BACKGROUND The literature indicates that chromosome 6 is involved in balanced translocation and is involved in reproductive failure. This aim of this study was to explore the clinical features of chromosome 6 translocation in male carriers. MATERIAL AND METHODS We identified 10 patients who were carriers of chromosome 6 translocations and excluded the patients with varicocele, ejaculatory duct obstruction, and the other cause of infertility. The karyotype was analyzed using G-banding. A search for translocations on chromosome 6 involved in male infertility was performed using PubMed. We included cases of balanced chromosome 6 translocations involving adult men of fertile age and excluded those cases of live-born children, or those without breakpoints involving chromosome 6, or those with complex chromosomal translocations or chimeras. RESULTS All 10 patients underwent genetic counseling for infertility. Semen analysis showed that 1 case had azoospermia, while 9 cases exhibited normal semen criteria. The respective partners of the 9 cases with normal semen parameters had a tendency to miscarry: 3 experienced spontaneous and induced abortion because of abnormal embryos; 3 experienced 3 incidents of spontaneous abortion, 2 experienced double spontaneous abortion, and 1 experienced biochemical pregnancy on 3 occasions. Most of the chromosome 6 breakpoints in translocation carriers obtained by the PubMed search were associated with spontaneous abortion. CONCLUSIONS Chromosome translocations involving chromosome 6 influence fertility status and lead to increased risk of miscarriage. Cytogenetic screening before opting for assisted reproductive technology and the breakpoints of chromosome 6 translocation should be considered for infertile male carriers.


Assuntos
Cromossomos Humanos Par 6/genética , Infertilidade Masculina/genética , Adulto , Pontos de Quebra do Cromossomo , Citogenética/métodos , Aconselhamento Genético , Heterozigoto , Humanos , Cariotipagem , Masculino , Análise do Sêmen , Translocação Genética/genética
20.
Bioinformatics ; 32(18): 2737-43, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27259542

RESUMO

MOTIVATION: In large-scale genetic association studies with tens of hundreds of single nucleotide polymorphisms (SNPs) genotyped, the traditional statistical framework of logistic regression using maximum likelihood estimator (MLE) to infer the odds ratios of SNPs may not work appropriately. This is because a large number of odds ratios need to be estimated, and the MLEs may be not stable when some of the SNPs are in high linkage disequilibrium. Under this situation, the P-value combination procedures seem to provide good alternatives as they are constructed on the basis of single-marker analysis. RESULTS: The commonly used P-value combination methods (such as the Fisher's combined test, the truncated product method, the truncated tail strength and the adaptive rank truncated product) may lose power when the significance level varies across SNPs. To tackle this problem, a group combined P-value method (GCP) is proposed, where the P-values are divided into multiple groups and then are combined at the group level. With this strategy, the significance values are integrated at different levels, and the power is improved. Simulation shows that the GCP can effectively control the type I error rates and have additional power over the existing methods-the power increase can be as high as over 50% under some situations. The proposed GCP method is applied to data from the Genetic Analysis Workshop 16. Among all the methods, only the GCP and ARTP can give the significance to identify a genomic region covering gene DSC3 being associated with rheumatoid arthritis, but the GCP provides smaller P-value. AVAILABILITY AND IMPLEMENTATION: http://www.statsci.amss.ac.cn/yjscy/yjy/lqz/201510/t20151027_313273.html CONTACT: liqz@amss.ac.cn SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Estudo de Associação Genômica Ampla , Desequilíbrio de Ligação , Modelos Estatísticos , Polimorfismo de Nucleotídeo Único , Bases de Dados Genéticas , Estudos de Associação Genética , Genômica , Genótipo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA