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1.
Cancer Cell Int ; 23(1): 230, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37794386

RESUMO

BACKGROUND: The purpose of this study was to investigate the role of hsa_circRNA_102051 in colorectal cancer (CRC) and its effect on the stemness of tumor cells. METHODS: CircRNA microarray was under analysis to screen differentially expressed novel circRNAs in the pathology of CRC. Quantitative real-time PCR was used to detect the relative RNA expression in CRC cells and samples. The effects of hsa_circRNA_102051 on biological functions in CRC cells were accessed both in vitro and in vivo. FISH, RIP and luciferase reporter assay were conducted to confirm the regulatory correlations between hsa_circRNA_102051 and miR-203a, as well as miR-203a and BPTF. Xenograft models were applied to further verify the impacts and fluctuations of hsa_circRNA_102051/miR-203a/BPTF. Moreover, the mechanism how hsa_circRNA_102051 affected the Notch signals was also elucidated. RESULTS: Hsa_circRNA_102051 was up-regulated in CRC tissues and cell lines, capable to promote the growth and invasion of CRC. In addition, hsa_circRNA_102051 could enhance stemness of CRC cells. BPTF was identified as downstream factors of hsa_circRNA_102051, and miR-203a was determined directly targeting both hsa_circRNA_102051 and BPTF as an intermediate regulator. Hsa_circRNA_102051 in CRC could block miR-203a expression, and subsequently activated BPTF. Hsa_circRNA_102051/miR-203a/BPTF axis modulated stemness of CRC cells by affecting Notch pathway. CONCLUSIONS: Our findings provided new clues that hsa_circRNA_102051 might be a potential predictive or prognostic factor in CRC, which induced the fluctuation of downstream miR-203a/BPTF, and subsequently influenced tumor growth, activities and stemness. Thereinto, the Notch signals were also involved. Hence, the hsa_circRNA_102051/miR-203a/BPTF axis could be further explored as a therapeutic target for anti-metastatic therapy in CRC patients.

2.
Transfus Med Hemother ; 382: 1-13, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35665313

RESUMO

Background: The outbreak of COVID-19 has resulted in more than 200 million infections and 4 million deaths. The blood derivative therapy represented by intravenous immunoglobulin (IVIG) and convalescent plasma (CP) therapy may be the promising therapeutics for COVID-19. Methods: A systematic article search was performed for eligible studies published up to August 3, 2021, through the PubMed, Embase, Cochrane Library. The included articles were screened by using rigorous inclusion and exclusion criteria. All analyses were conducted using Review Manager 5.4. Quality of studies and risk of bias were evaluated. Results: A total of 5 IVIG therapy and 13 CP therapy randomized controlled trials were included with a sample size of 13,696 subjects diagnosed with COVID-19. IVIG could reduce the mortality compared with the control group (RR 0.65, 95% CI: 0.46-0.93, p = 0.02). The use of CP did not effectively reduce the mortality (RR 0.97, 95% CI: 0.91-1.03, p = 0.38), the length of hospital stay (MD -0.47, 95% CI: -4.13 to 3.20, p = 0.80), and the mechanical ventilation use (RR = 0.98, 95% CI: 0.89-1.07, p = 0.62) of the patients with COVID-19. Treatment with IVIG or CP was not significantly associated with an increase in reported adverse events (RR 1.07, 95% CI: 0.94-1.22, p = 0.28). Conclusions: Treatment with IVIG could be effective and safe to improve survival for patients with COVID-19. But the benefit of CP in the treatment of COVID-19 is limited. The certainty of the evidence was moderate for all outcomes.

3.
Environ Monit Assess ; 194(3): 168, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35146588

RESUMO

How and to which extent terrain factors affecting the drainage area threshold (DAT) are disputable. This paper uses principal component analysis (PCA) and correlation analysis to study the influence degree of terrain factors on DAT. Firstly, 22 watersheds, locating in the severe soil erosion region (SSER) of Loess Plateau of China, are picked out as the example areas. The purpose of the mean change point method (MCP) to detect the relationship between DAT and gully density (GD) is to get a reasonable DAT. Secondly, nine terrain factors are calculated, and their statistical values are compared and put in the matrix to clear the different effects on DAT. Finally, the effects of statistical eigenvalues of terrain factors on DAT are compared with PCA and the correlation analysis. According to the PCA, the nine terrain factors are summarized into three principal components, which are slope, height variation, and relief factor. By calculating the score weighted by each factor coefficient matrix and eigenvalue, the result states that slope (S), terrain curvatures (K), and surface roughness (SR) are the factors that have great influence on DAT. Meanwhile, the results of correlation analysis indicate that S, SR, and K have exerted a great influence on the DAT, and the significance level was above 0.05. Both the results of PCA and correlation analysis make clear that the slope is the most direct and influential factor affecting DAT, while other factors are more or less related to slope directly and indirectly. The result implies that the vertical variation of terrain has a strong correlation with the slope, and also has a great influence on DAT. This research not only would be of great significance to recognize the mechanism of gully development, but also able to provide a scientific reference for soil and water conservation in the Loess Plateau.


Assuntos
Monitoramento Ambiental , Solo , China , Análise de Componente Principal
4.
Genet Epidemiol ; 44(1): 41-51, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31520493

RESUMO

Individual sequencing studies often have limited sample sizes and so limited power to detect trait associations with rare variants. A common strategy is to aggregate data from multiple studies. For studying rare variants, jointly calling all samples together is the gold standard strategy but can be difficult to implement due to privacy restrictions and computational burden. Here, we compare joint calling to the alternative of single-study calling in terms of variant detection sensitivity and genotype accuracy as a function of sequencing coverage and assess their impact on downstream association analysis. To do so, we analyze deep-coverage (~82×) exome and low-coverage (~5×) genome sequence data on 2,250 individuals from the Genetics of Type 2 Diabetes study jointly and separately within five geographic cohorts. For rare single nucleotide variants (SNVs): (a) ≥97% of discovered SNVs are found by both calling strategies; (b) nonreference concordance with a set of highly accurate genotypes is ≥99% for both calling strategies; (c) meta-analysis has similar power to joint analysis in deep-coverage sequence data but can be less powerful in low-coverage sequence data. Given similar data processing and quality control steps, we recommend single-study calling as a viable alternative to joint calling for analyzing SNVs of all minor allele frequency in deep-coverage data.


Assuntos
Diabetes Mellitus Tipo 2/genética , Frequência do Gene/genética , Polimorfismo de Nucleotídeo Único/genética , Exoma/genética , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos
5.
J Cell Physiol ; 235(2): 1733-1745, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31317555

RESUMO

In the last decade, circular RNAs (circRNAs) emerge as important regulators in multiple biological processes. Lately, it is reported hsa_circRNA_103809 could play vital parts in several types of cancers. Based on the analysis of GEO data (GSE97332), hsa_circRNA_103809 was found to be dysregulated in hepatocellular carcinoma (HCC). However, the biological function and underlying regulatory mechanisms of hsa_circRNA_103809 in HCC remain unclear. Our results suggested that hsa_circRNA_103809 was overexpressed in HCC patients, and hsa_circRNA_103809 knockdown remarkably inhibited the proliferation, cycle progression, and migration of HCC cells. The investigations of molecular showed that hsa_circRNA_103809 could elevate the protein expression of a miR-377-3p target, fibroblast growth factor receptor 1 (FGFR1), through interacting with miR-377-3p and decreasing its expression level. Additionally, in vivo assays revealed hsa_circRNA_103809 short hairpin RNA served as a tumor suppressor through downregulating FGFR1 in HCC. This study systematically investigated novel regulatory signaling of hsa_circRNA_103809/miR-377-3p/FGFR1 axis, providing insights into hepatocellular carcinoma treatment from bench to clinic.


Assuntos
Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Hepáticas/patologia , RNA Circular/genética , Transdução de Sinais/genética , Adulto , Idoso , Animais , Carcinoma Hepatocelular/genética , Feminino , Xenoenxertos , Humanos , Neoplasias Hepáticas/genética , Sistema de Sinalização das MAP Quinases/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo
6.
Am J Hum Genet ; 100(6): 865-884, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28552196

RESUMO

Deep sequence-based imputation can enhance the discovery power of genome-wide association studies by assessing previously unexplored variation across the common- and low-frequency spectra. We applied a hybrid whole-genome sequencing (WGS) and deep imputation approach to examine the broader allelic architecture of 12 anthropometric traits associated with height, body mass, and fat distribution in up to 267,616 individuals. We report 106 genome-wide significant signals that have not been previously identified, including 9 low-frequency variants pointing to functional candidates. Of the 106 signals, 6 are in genomic regions that have not been implicated with related traits before, 28 are independent signals at previously reported regions, and 72 represent previously reported signals for a different anthropometric trait. 71% of signals reside within genes and fine mapping resolves 23 signals to one or two likely causal variants. We confirm genetic overlap between human monogenic and polygenic anthropometric traits and find signal enrichment in cis expression QTLs in relevant tissues. Our results highlight the potential of WGS strategies to enhance biologically relevant discoveries across the frequency spectrum.


Assuntos
Antropometria , Genoma Humano , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas/genética , Análise de Sequência de DNA/métodos , Estatura/genética , Estudos de Coortes , Metilação de DNA/genética , Bases de Dados Genéticas , Feminino , Variação Genética , Humanos , Lipodistrofia/genética , Masculino , Metanálise como Assunto , Obesidade/genética , Mapeamento Físico do Cromossomo , Caracteres Sexuais , Síndrome , Reino Unido
7.
Cell Biol Toxicol ; 36(4): 333-347, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31902050

RESUMO

OBJECTIVES: LncRNAs (long noncoding RNAs) have been reported to critically regulate colorectal cancer (CRC). We prospectively investigated effects and mechanisms of lncRNA LINC00858 on regulation of CRC progression. METHODS: Expression of LINC00858 and its target were analyzed by quantitative real-time polymerase chain reaction and in situ hybridization. MTT and bromodeoxyuridine/5-bromo-2'-deoxyuridine (BrdU) staining to assess cell proliferation ability. Flow cytometry, wound healing, and transwell assays were conducted to evaluate cell apoptosis, migration, and invasion, respectively. Interaction between LINC00858 and its target was confirmed by luciferase activity assay and RNA immunoprecipitation. Subcutaneous xenotransplanted tumor model was established and employed to detect tumorigenic functions of LINC00858, and further evaluated by qRT-PCR, western blot, immunohistochemistry, and hematoxylin and eosin staining. RESULTS: With a predicted poor prognosis, LINC00858 was upregulated in CRC patients. LINC00858 knockdown suppressed cell proliferation, invasion, and migration abilities, meanwhile induced cell apoptosis. Moreover, LINC00858 could target and inhibit the miR-4766-5p expression, thus promoting CRC progression. miR-4766-5p further suppressed serine/threonine kinase PAK2. Interestingly, interference of LINC00858 suppressed tumorigenic ability of CRC in vivo by downregulating PAK2. CONCLUSIONS: LINC00858 promoted CRC progression by sponging miR-4766 to upregulate PAK2, shedding lights on LINC00858 as a potential therapeutic target candidate in CRC treatment from bench to clinic.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/genética , RNA Longo não Codificante/genética , Quinases Ativadas por p21/genética , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Regulação para Cima
8.
Carcinogenesis ; 40(4): 560-568, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-30403769

RESUMO

Colon tumor is a conman tumor in the world. There are various kinds of cells in colon tumor bulk, and only a small population can initiate tumor efficiently and termed as tumor-initiating cells (TICs). With self-renewal and differentiation capacities, colon TICs drive colon tumorigenesis, metastasis and relapse. However, the molecular mechanisms of colon TICs self-renewal are elusive. Here, we found that circular RNA (circCTIC1) was highly expressed in colon tumor and colon TICs. circCTIC1 knockdown impaired the self-renewal of colon TICs, and its overexpression played an opposite role. circCTIC1 promoted the expression of c-Myc and drove the self-renewal of colon TIC through c-Myc-dependent manner. circCTIC1 interacted with nuclear remodeling factor (NURF) complex, recruited NURF complex onto c-Myc promoter and finally drove the transcriptional initiation of c-Myc. Altogether, circCTIC1 drove the self-renewal of colon TICs through bromodomain PHD finger transcription factor (BPTF)-mediated c-Myc expression.


Assuntos
Antígenos Nucleares/metabolismo , Autorrenovação Celular , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Células-Tronco Neoplásicas/patologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Circular/genética , Fatores de Transcrição/metabolismo , Animais , Antígenos Nucleares/genética , Apoptose , Proliferação de Células , Transformação Celular Neoplásica , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Proteínas do Tecido Nervoso/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , Transdução de Sinais , Fatores de Transcrição/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Acoust Soc Am ; 144(6): 3514, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30599690

RESUMO

Metamaterial provides a promising way to control low-frequency noise, but its narrow bandgap limits its applications. To end this, a membrane-type smart metamaterial with multi-modal sound insulation property is studied. The proposed metamaterial consists of an aluminum membrane bonded with multi-modal resonant piezoelectric resonators. Both simulated and experimental results show that the proposed metamaterial can broaden the locally resonant bandgaps because of the effect of the multi-modal resonance (the percent bandwidths are 0.19 and 0.22 for the lowest mode and higher two modes, respectively). Large multi-modal sound insulations (over 37 dB) are obtained around the designed resonant frequencies in low frequency regime (<2000 Hz) with an ultra-thin thickness (over 1000 times thinner than the acoustic wavelength). It is also demonstrated that the excellent sound insulation property can be tuned by simply adjusting the external circuits instead of modifying the structure itself. The underlying mechanism of the unusual sound insulation of the proposed metamaterial is attributed to the negative effective bending stiffness Deq derived by the effective medium method. In addition, the parametric study shows that the circuital parameters (capacitances) are inversely related to the sound transmission loss of the proposed multi-resonant metamaterial, which benefits the optimization of insulation effect.

10.
Sensors (Basel) ; 18(10)2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30261602

RESUMO

On-line vibration monitoring is significant for high-speed rotating blades, and blade tip-timing (BTT) is generally regarded as a promising solution. BTT methods must assume that rotating speeds are constant. This assumption is impractical, and blade damages are always formed and accumulated during variable operational conditions. Thus, how to carry out BTT vibration monitoring under variable rotation speed (VRS) is a big challenge. Angular sampling-based order analyses have been widely used for vibration signals in rotating machinery with variable speeds. However, BTT vibration signals are well under-sampled, and Shannon's sampling theorem is not satisfied so that existing order analysis methods will not work well. To overcome this problem, a reconstructed order analysis-based BTT vibration monitoring method is proposed in this paper. First, the effects of VRS on BTT vibration monitoring are analyzed, and the basic structure of angular sampling-based BTT vibration monitoring under VRS is presented. Then a band-pass sampling-based engine order (EO) reconstruction algorithm is proposed for uniform BTT sensor configuration so that few BTT sensors can be used to extract high EOs. In addition, a periodically non-uniform sampling-based EO reconstruction algorithm is proposed for non-uniform BTT sensor configuration. Next, numerical simulations are done to validate the two reconstruction algorithms. In the end, an experimental set-up is built. Both uniform and non-uniform BTT vibration signals are collected, and reconstructed order analysis are carried out. Simulation and experimental results testify that the proposed algorithms can accurately capture characteristic high EOs of synchronous and asynchronous vibrations under VRS by using few BTT sensors. The significance of this paper is to overcome the limitation of conventional BTT methods of dealing with variable blade rotating speeds.

11.
Molecules ; 22(5)2017 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-28481323

RESUMO

An efficient, convenient, and eco-friendly biocatalytic approach was developed for the synthesis of quinoline derivatives via the α-chymotrypsin-catalyzed Friedländer reaction. Interestingly, α-chymotrypsin exhibited higher catalytic activity in an ionic liquid (IL) aqueous solution as compared to that observed in our previous relevant study, which was conducted using an organic solvent, and a series of substrates gave similar excellent yields at lower reaction temperature and under reduced enzyme-loading conditions.


Assuntos
Quimotripsina/química , Líquidos Iônicos/química , Quinolinas/química , Quinolinas/síntese química , Catálise
12.
Sensors (Basel) ; 16(9)2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27589767

RESUMO

Electrostatic sensor arrays (ESAs) are promising in industrial applications related to charged particle monitoring. Sensitivity is a fundamental and commonly-used sensing characteristic of an ESA. However, the usually used spatial sensitivity, which is called static sensitivity here, is not proper for moving particles or capable of reflecting array signal processing algorithms integrated in an ESA. Besides, reports on ESAs for intermittent particles are scarce yet, especially lacking suitable array signal processing algorithms. To solve the problems, the dynamic sensitivity of ESA is proposed, and a hemisphere-shaped electrostatic sensors' circular array (HSESCA) along with its application in intermittent particle monitoring are taken as an example. In detail, a sensing model of the HSESCA is built. On this basis, its array signals are analyzed; the dynamic sensitivity is thereupon defined by analyzing the processing of the array signals. Besides, a component extraction-based array signal processing algorithm for intermittent particles is proposed, and the corresponding dynamic sensitivity is analyzed quantitatively. Moreover, simulated and experimental results are discussed, which validate the accuracy of the models and the effectiveness of the relevant approaches. The proposed dynamic sensitivity of ESA, as well as the array signal processing algorithm are expected to provide references in modeling, designing and using ESAs.

13.
Sensors (Basel) ; 15(2): 2419-37, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25621612

RESUMO

High-speed blades are often prone to fatigue due to severe blade vibrations. In particular, synchronous vibrations can cause irreversible damages to the blade. Blade tip-timing methods (BTT) have become a promising way to monitor blade vibrations. However, synchronous vibrations are unsuitably monitored by uniform BTT sampling. Therefore, non-equally mounted probes have been used, which will result in the non-uniformity of the sampling signal. Since under-sampling is an intrinsic drawback of BTT methods, how to analyze non-uniformly under-sampled BTT signals is a big challenge. In this paper, a novel reconstruction method for non-uniformly under-sampled BTT data is presented. The method is based on the periodically non-uniform sampling theorem. Firstly, a mathematical model of a non-uniform BTT sampling process is built. It can be treated as the sum of certain uniform sample streams. For each stream, an interpolating function is required to prevent aliasing in the reconstructed signal. Secondly, simultaneous equations of all interpolating functions in each sub-band are built and corresponding solutions are ultimately derived to remove unwanted replicas of the original signal caused by the sampling, which may overlay the original signal. In the end, numerical simulations and experiments are carried out to validate the feasibility of the proposed method. The results demonstrate the accuracy of the reconstructed signal depends on the sampling frequency, the blade vibration frequency, the blade vibration bandwidth, the probe static offset and the number of samples. In practice, both types of blade vibration signals can be particularly reconstructed by non-uniform BTT data acquired from only two probes.

14.
Sensors (Basel) ; 14(8): 14021-37, 2014 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-25090419

RESUMO

Electrostatic sensors have been widely used in many applications due to their advantages of low cost and robustness. Their spatial sensitivity and time-frequency characteristics are two important performance parameters. In this paper, an analytical model of the induced charge on a novel hemisphere-shaped electrostatic sensor was presented to investigate its accurate sensing characteristics. Firstly a Poisson model was built for electric fields produced by charged particles. Then the spatial sensitivity and time-frequency response functions were directly derived by the Green function. Finally, numerical calculations were done to validate the theoretical results. The results demonstrate that the hemisphere-shaped sensors have highly 3D-symmetrical spatial sensitivity expressed in terms of elementary function, and the spatial sensitivity is higher and less homogeneous near the hemispherical surface and vice versa. Additionally, the whole monitoring system, consisting of an electrostatic probe and a signal conditioner circuit, acts as a band-pass filter. The time-frequency characteristics depend strongly on the spatial position and velocity of the charged particle, the radius of the probe as well as the equivalent resistance and capacitance of the circuit.


Assuntos
Análise Numérica Assistida por Computador/instrumentação , Eletricidade Estática , Capacitância Elétrica , Eletricidade , Modelos Teóricos , Sensibilidade e Especificidade
15.
Cancer Biomark ; 40(1): 95-109, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306025

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a common form of cancer, with rectal cancer accounting for approximately one-third of all cases. Among rectal cancers, 95% are classified as rectal adenocarcinoma (READ). Emerging evidence suggests that long noncoding RNAs (lncRNAs) play a significant role in the development and progression of various cancers. In our study, we aimed to identify differentially expressed lncRNAs potentially associated with m6A and establish a risk assessment model to predict clinical outcomes for READ patients. METHODS: The READ dataset from the TCGA database was utilized in this study to synergistically and logically integrate m6A and lncRNA, while employing bioinformatics technology for the identification of suitable biomarkers. A risk prediction model comprising m6A-associated lncRNAs was constructed to investigate the prognostic, diagnostic, and biological functional relevance of these m6A-related lncRNAs. RESULTS: Our research builds a composed of three related to m6A lncRNA rectal gland cancer prognosis model, and the model has been proved in the multi-dimensional can serve as the potential of the prognosis of rectal gland cancer biomarkers. Our study constructed a prognostic model of rectal adenocarcinoma consisting of three related m6A lncRNAs: linc00702, ac106900.1 and al583785.1. CONCLUSION: The model has been validated as a potential prognostic biomarker for rectal cancer in multiple dimensions, aiming to provide clinicians with an indicator to assess the duration of straight adenocarcinoma. This enables early detection of rectal cancer and offers a promising target for immunotherapy.


Assuntos
Adenocarcinoma , Biomarcadores Tumorais , Biologia Computacional , RNA Longo não Codificante , Neoplasias Retais , Humanos , Neoplasias Retais/genética , Neoplasias Retais/imunologia , Neoplasias Retais/patologia , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Biologia Computacional/métodos , Prognóstico , Biomarcadores Tumorais/genética , RNA Longo não Codificante/genética , Regulação Neoplásica da Expressão Gênica , Masculino , Feminino
16.
Malar J ; 12: 30, 2013 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-23347639

RESUMO

BACKGROUND: Malaria is a significant public health concern in Haiti where approximately 30,000 cases are reported annually with CDC estimates as high as 200,000. Malaria infections in Haiti are caused almost exclusively by Plasmodium falciparum, while a small number of Plasmodium malariae and an even smaller number of putative Plasmodium vivax infections have been reported. The lack of confirmed P. vivax infections in Haiti could be due to the genetic background of native Haitians. Having descended from West African populations, many Haitians could be Duffy negative due to a single nucleotide polymorphism from thymine to cytosine in the GATA box of the promoter region of the Duffy antigen receptor for chemokines (DARC) gene. This mutation, encoded by the FYES allele, eliminates the expression of the Duffy antigen on erythrocytes, which reduces invasion by P. vivax. This study investigated the frequency of the FYES allele and P. vivax infections in malaria patients with the goal of uncovering factors for the lack of P. vivax infections reported in Haiti. METHODS: DNA was extracted from dried blood spots collected from malaria patients at four clinic locations in Haiti. The samples were analysed by polymerase chain reaction (PCR) for the presence of the P. vivax small subunit ribosomal RNA gene. PCR, sequencing, and restriction enzyme digestion were used to detect the presence of the FYES allele. Matched samples were examined for both presence of P. vivax and the FYES allele. RESULTS: No cases of P. vivax were detected in any of the samples (0/136). Of all samples tested for the FYES allele, 99.4% had the FYES allele (163/164). Of the matched samples, 99% had the FYES allele (98/99). CONCLUSIONS: In this preliminary study, no cases of P. vivax were confirmed by PCR and 99% of the malaria patients tested carried the FYES allele. The high frequency of the FYES allele that silences erythroid expression of the Duffy antigen offers a biologically plausible explanation for the lack of P. vivax infections observed. These results provide insights on the host susceptibility for P. vivax infections that has never before been investigated in Haiti.


Assuntos
Resistência à Doença , Sistema do Grupo Sanguíneo Duffy/genética , Malária Vivax/genética , Receptores de Superfície Celular/genética , Frequência do Gene , Haiti , Humanos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Análise de Sequência de DNA
17.
ScientificWorldJournal ; 2013: 894851, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24348192

RESUMO

The temperature data from 3 meteorological stations (Kashi, Ruoqiang, and Hotan) in the South of Tarim River Basin (STRB) during 1964-2011 were analyzed by Mann-Kendall test and correlation analysis. The results from Mann-Kendall test show that the surface temperature (ST), 850 hPa temperature (T850), and 700 hPa temperature (T700) exhibited upward trends, while 300 hPa temperature (T300) revealed a downward trend. On the whole, the change rate of ST, T850, T700, and T300 was 0.26~0.46°C/10a, 0.15~0.40°C/10a, 0.03~0.10°C/10a, and -0.38~-0.13°C/10a, respectively. For the periods, ST and T850 declined during 1964-1997 and then rose during 1998-2011. T700 declined during 1964-2005 and then rose during 2006-2011, while T300 rose from 1964 to 1970s and then declined. The results from correlation analysis show that T850 and T700 positively correlated with ST (P<0.01) at the all three stations and there was a negative correlation between T300 and ST at Hotan (P<0.1), while the correlation is not significant at Kashi and Ruoqiang. The results indicate that there were gradient differences in the response of upper-air temperature (UT) to ST change.


Assuntos
Ar , Rios , Temperatura , China , Monitoramento Ambiental , Geografia
18.
Syst Rev ; 11(1): 256, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36443888

RESUMO

BACKGROUND: Blood derivatives therapy is a conventional clinical treatment, while the treatment for Alzheimer's disease (AD) is relatively novel. To provide clinical references for treating AD, this meta-analysis was performed to evaluate the efficacy and safety of blood derivatives therapy on the patients with AD. METHODS: A systematic articles search was performed for eligible studies published up to December 6, 2021 through the PubMed, Embase, Cochrane library, ClinicalTrials.gov , Chinese National Knowledge Infrastructure database, and Wanfang databases. The included articles were screened by using rigorous inclusion and exclusion criteria. Study selection and data-extraction were performed by two authors independently. Random effects model or fixed effects model was used. Quality of studies and risk of bias were evaluated according to the Cochrane risk of bias tool. All analyses were conducted using Review Manager 5.4. The study was designed and conducted according to the Preferring Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. RESULTS: A total of three plasma administrations (two plasma exchange and one young plasma infusion) and five intravenous immunoglobulin (IVIG) randomized controlled trials with a sample size of 1148 subjects diagnosed with AD were included. There was no significant difference in cognitive improvement and all-cause discontinuation between intervention and placebo groups (RR 1.10, 95% CI 0.79-1.54). And Intervention groups showed not a statistically significant improvement in cognition of included subjects measured by the ADAS-Cog (MD 0.36, 95% CI 0.87-1.59), ADCS-ADL (MD -1.34, 95% CI - 5.01-2.32) and NPI (MD 2.20, 95% CI 0.07-4.32) score compared to the control groups. IVIG is well tolerated for AD patients even under the maximum dose (0.4 g/kg), but it is inferior to placebo in Neuropsychiatric Inventory scale in AD patients (MD 2.19, 95% CI 0.02-4.37). CONCLUSIONS: The benefits of blood derivatives therapy for AD are limited. It is necessary to perform well-designed randomized controlled trials with large sample sizes focusing on the appropriate blood derivatives for the specific AD sub-populations in the future. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42021233886.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Imunoglobulinas Intravenosas , Cognição , Grupos Controle , Plasmaferese
19.
Sci Bull (Beijing) ; 67(5): 547-556, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36546176

RESUMO

Reconstruction of natural streamflow is fundamental to the sustainable management of water resources. In China, previous reconstructions from sparse and poor-quality gauge measurements have led to large biases in simulation of the interannual and seasonal variability of natural flows. Here we use a well-trained and tested land surface model coupled to a routing model with flow direction correction to reconstruct the first high-quality gauge-based natural streamflow dataset for China, covering all its 330 catchments during the period from 1961 to 2018. A stronger positive linear relationship holds between upstream routing cells and drainage areas, after flow direction correction to 330 catchments. We also introduce a parameter-uncertainty analysis framework including sensitivity analysis, optimization, and regionalization, which further minimizes biases between modeled and inferred natural streamflow from natural or near-natural gauges. The resulting behavior of the natural hydrological system is represented properly by the model which achieves high skill metric values of the monthly streamflow, with about 83% of the 330 catchments having Nash-Sutcliffe efficiency coefficient (NSE) > 0.7, and about 56% of the 330 catchments having Kling-Gupta efficiency coefficient (KGE) > 0.7. The proposed construction scheme has important implications for similar simulation studies in other regions, and the developed low bias long-term national datasets by statistical postprocessing should be useful in supporting river management activities in China.


Assuntos
Rios , Recursos Hídricos , Simulação por Computador , Hidrologia , China
20.
G3 (Bethesda) ; 11(2)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33585870

RESUMO

Over the last decade, GWAS meta-analyses have used a strict P-value threshold of 5 × 10-8 to classify associations as significant. Here, we use our current understanding of frequently studied traits including lipid levels, height, and BMI to revisit this genome-wide significance threshold. We compare the performance of studies using the P = 5 × 10-8 threshold in terms of true and false positive rate to other multiple testing strategies: (1) less stringent P-value thresholds, (2) controlling the FDR with the Benjamini-Hochberg and Benjamini-Yekutieli procedure, and (3) controlling the Bayesian FDR with posterior probabilities. We applied these procedures to re-analyze results from the Global Lipids and GIANT GWAS meta-analysis consortia and supported them with extensive simulation that mimics the empirical data. We observe in simulated studies with sample sizes ∼20,000 and >120,000 that relaxing the P-value threshold to 5 × 10-7 increased discovery at the cost of 18% and 8% of additional loci being false positive results, respectively. FDR and Bayesian FDR are well controlled for both sample sizes with a few exceptions that disappear under a less stringent definition of true positives and the two approaches yield similar results. Our work quantifies the value of using a relaxed P-value threshold in large studies to increase their true positive discovery but also show the excess false positive rates due to such actions in modest-sized studies. These results may guide investigators considering different thresholds in replication studies and downstream work such as gene-set enrichment or pathway analysis. Finally, we demonstrate the viability of FDR-controlling procedures in GWAS.


Assuntos
Estudo de Associação Genômica Ampla , Teorema de Bayes , Simulação por Computador , Fenótipo , Probabilidade
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