Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.244
Filtrar
1.
Biosens Bioelectron ; 147: 111788, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31671380

RESUMO

The sensitive imaging of telomerase RNA (TR) in living cells is crucial for improved guidance in cancer clinical diagnosis because its expression level is closely related to malignant diseases. The efficient delivery of multiple nucleic acid probes to target cells is critical for nucleic acid-based methods to successfully image low-abundance TR in living cells. While novel nanomaterials enhance delivery efficiency, uncontrolled loading and slow intracellular release remain major challenges for multiple-probe delivery. Here, we designed a facile DNA/RNA nanoflower (NF) to perform the controlled loading of multiple probes and rapid intracellular release based on the "zipper lock-and-key" strategy. First, a long RNA generated by rolling circle transcription acts as both the "smart zipper lock" and the delivery carrier to alternately lock multiple functional DNAs through DNA-RNA base pairing, and the resulting RNA/DNA hybrids self-assemble into packed NFs. The functional DNAs include the fluorescence molecular beacon H1 for TR recognition, H2 for hybrid chain reaction (HCR) and DNA-cholesterol for size control. After NF internalization by the cells, the intracellular RNase H acts as the "key" to specifically open the DNA/RNA NFs by cleaving the RNA in the DNA/RNA hybrid, releasing high amounts of H1 and H2 in a confined space and thereby facilitating the HCR amplification analysis of cytoplasmic TR. With the addition of a DNA-nuclear localization peptide component in the same NF, nuclear TR can also be sensitively detected. Compared with the regular H1/H2 mixture, the DNA/RNA NFs produced a higher-contrast fluorescence signal. This indicated that the proposed strategy allowed the side arms of H1/H2 to be sealed into the RNA sequence-programmed "zipper lock" by controlled loading, avoiding mutual nonspecific H1/H2 hybridization. In addition, due to the fast kinetics of the RNase endonuclease reaction, the loaded H1/H2 was quickly released. Furthermore, the strategy was successfully used to assay the expression levels of TR in HeLa, HepG2 and HL-7702 cells, demonstrating that this approach holds the potential for the sensitive detection of low-abundance biomarkers in living cells.

2.
Adv Exp Med Biol ; 1179: 137-186, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31741336

RESUMO

Chronic hepatitis B (CHB) remains the leading cause of liver-related morbidity and mortality across the world. If left untreated, approximately one-third of these patients will progress to severe end-stage liver diseases including liver failure, cirrhosis, and hepatocellular carcinoma (HCC). High level of serum HBV DNA is strongly associated with the development of liver failure, cirrhosis, and HCC. Therefore, antiviral therapy is crucial for the clinical management of CHB. Current antiviral drugs including nucleoside/nucleotide analogues (NAs) and interferon-α (IFN-α) can suppress HBV replication and reduce the progression of liver disease, thus improving the long-term outcomes of CHB patients. This chapter will discuss the standard and optimization antiviral therapies in treatment-naïve and treatment-experienced patients, as well as in the special populations. The up-to-date advances in the development of new anti-HBV agents will be also discussed. With the combination of the current antiviral drugs and the newly developed antiviral agents targeting the different steps of the viral life cycle or the newly developed agents modulating the host immune responses, the ultimate eradication of HBV will be achieved in the future.


Assuntos
Antivirais , Hepatite B Crônica , Antivirais/farmacologia , Antivirais/uso terapêutico , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Humanos
3.
J Nanosci Nanotechnol ; 20(4): 2395-2401, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492253

RESUMO

In this paper, ß-Ga2O3 nanowires were synthesized by vapor transport method at different temperatures. The as-prepared samples were analyzed for crystal structure by X-ray diffraction (XRD), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), and for morphology using scanning electron microscopy (SEM). The results show that the Ga2O3 nanowires present a monoclinic structure, the length and diameter of the Ga2O3 nanowires increased with the growth temperature. A majority of the Ga2O3 nanowires present longitudinal twinning structures. A broad photoluminescence emission band was observed from the Ga2O3 nanowires at room temperature, which is caused by different kinds of vacancy defects. Our study shows an unusual twinning structure of ß-Ga2O3 nanowires, which may be helpful to understand the growth mechanism of nanowires.

4.
Ecotoxicol Environ Saf ; 187: 109823, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31639641

RESUMO

Time-dependent cross-phenomenon in which the cross between the actual concentration-response curve (CRC) for mixture crosses the CRCs for reference model varies with time has been frequently reported in previous studies, expressed as a heterogeneous pattern of joint toxic action. However, the variation tendency of time-dependent cross-phenomenon is rarely addressed. In this study, the joint toxic actions of binary antibacterial mixtures (i.e., two quorum sensing inhibitors, tetracycline hydrochloride, erythromycin, and chloramphenicol with sulfonamides) were judged using independent action (IA) model to find the variation tendency of time-dependent cross-phenomenon. The results show that the time-dependent cross-phenomena of the test binary antibacterial mixtures follow a unified variation tendency and the corresponding joint toxic actions change regularly with an increase of both concentration and time. Through investigating the relationship between the stimulatory and inhibitory modes of action for the single agents and the time-dependent cross-phenomena of binary mixtures, the regular time-dependent cross-phenomena is speculated to be derived from the hormetic effects of the components in the mixtures. This study offers an advance for the variation tendency and mechanistic explanation of time-dependent cross-phenomenon, which will provide a support for the future development in the exploration of time-dependent cross-phenomenon and environmental risk assessment of pollutant mixtures.

5.
Theriogenology ; 141: 9-15, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31479777

RESUMO

Artificial insemination (AI) has been used as a routine technology globally in the pig production industry since 1930. One of the preferable advantages of AI technology is that the semen of elite boars can be disseminated to the commercial sow population rapidly. Understanding the genetic background of semen traits may help in developing genetic improvement programs of boars by including these traits into the selection index. In this study, we utilized weighted single-step genome-wide association study (wssGWAS) to identify genetic regions and further candidate genes associated with sperm morphology abnormalities (proximal droplet, distal droplet, bent tail, coiled tail, and distal midpiece reflex) in a Duroc boar population. Several genomic regions explained 2.76%-9.22% of the genetic variances for sperm morphology abnormalities were identified. The first three detected QTL regions together explained about 7.65%-25.10% of the total genetic variances of the studied traits. Several genes were detected and considered as candidate genes for each of the traits under study: coiled tail, HOOK1, ARSA, SYCE3, SOD3, GMNN, RBPJ, STIL, and FGF1; bent tail, FGF1, ADIPOR1, ARPC5, FGFR3, PANX1, IZUMO1R, ANKRD49, and GAL; proximal droplet, NSF, WNT3, WNT9B, LYZL6, FGFR1OP, RNASET2, FYN, LRRC6, EPC1, DICER1, FNDC3A, and PFN1; distal droplet, ARSA, SYCE3, MOV10L1, CBR1, KDM6B, TP53, PTBP2, UBR7, KIF18A, ADAM15, FAAH, TEKT3, and SRD5A1; and distal midpiece reflex, OMA1, PFN1, PELP1, BMP2, GPR18, TM9SF2, and SPIN1. GO and KEGG enrichment analysis revealed the potential function of the identified candidate genes in spermatogenesis, testis functioning, and boar spermatozoa plasma membrane activating and maintenance. In conclusion, we detected candidate genes associated with the coiled tail, bent tail, proximal droplet, distal droplet, and distal midpiece reflex in a Duroc boar population using wssGWAS. Overall, these novel results reflect the polygenic genetic architecture of the studied sperm morphology abnormality traits, which may provide knowledge for conducting genomic selection on these traits. The detected genetic regions can be used in developing trait-specific marker assisted selection models by assigning higher genetic variances to these regions.

6.
Water Environ Res ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31697421

RESUMO

Wastewater produced by the textile industry containing azo dyes and anthraquinone dyes is significant source of pollution to the environment and is toxic for aquatic life. To overcome the high-energy cost of traditional electrochemical oxidation, a custom-built power supply device for the degradation of anthraquinone and azo dyes by low voltage of 15.0-20.0 V pulsed discharge was investigated. Titanium coated with mixed oxide (Ti/IrO2 -RuO2 -SnO2 ) plates and pure titanium plates were used as the anode and cathode, respectively, for the generation of chlorine in the dye solution. For the anthraquinone dye Reactive Blue 19, 60.0% of the chemical oxygen demand (COD) and 22.0% of the total organic carbon (TOC) were removed using this system. A comparison of the direct current electrolysis and pulsed discharge revealed that using the pulsed discharge method reduced the energy cost by 68.6%. UV-visible, LC-MS, and GC-MS were used to identify the intermediate compounds formed during the degradation of Reactive Blue 19. The results indicate that in the process of oxidation by chlorine/hypochlorite, the chromophore group was first oxidized to -NH2 , followed by decolorization via chlorination of the aromatic rings. The results confirm that low-voltage pulse electrolysis can be used for the degradation of industrial dyes in waste effluents. PRACTITIONER POINTS: Low-voltage pulse electrolysis can be used for the degradation of industrial dyes and/or dyes in waste effluents. For anionic dye Reactive Blue 19, 60.0% of COD and 22.0% of TOC were removed using low-voltage (20.0 V) pulse electrolysis. The pulsed discharge method reduced the energy cost of this degradation process by 68.6% compared with direct current electrolysis. The intermediate compounds formed during the degradation of Reactive Blue 19 were confirmed by UV-visible spectroscopy, LC-MS, and GC-MS.

7.
Int J Med Robot ; : e2056, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713946

RESUMO

BACKGROUND: Current soft endoscope intervention mainly depends on the skills of endoscopists, especially for the orientation of the endoscope within the human tortuous lumen. This dependence causes inefficient and time-consuming surgery. METHODS: A human-robot cooperation navigation strategy is proposed to perform the intervention of soft endoscope. The navigation strategy firstly detects the cavity center by processing the image of endoscope, then an auto-orienting strategy is presented to automatically adjust the endoscope pointing to the detected cavity center. RESULTS: Human phantom experiments are carried out to validate the effectiveness and feasibility of the navigation strategy. The results show that the cavity center is accurately extracted with whether the cavity is occluded or not and the auto-orienting strategy could well point the endoscope around the cavity center. CONCLUSION: The proposed human-robot cooperation navigation strategy releases endoscopists from the time-consuming operations and improves the safety and automation of intervention procedures.

8.
Eur J Radiol ; 121: 108735, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31733432

RESUMO

PURPOSE: The study is to explore potential features and develop classification models for distinguishing benign and malignant lung lesions based on CT-radiomics features and PET metabolic parameters extracted from PET/CT images. MATERIALS AND METHODS: A retrospective study was conducted in baseline 18 F-flurodeoxyglucose positron emission tomography/ computed tomography (18 F-FDG PET/CT) images of 135 patients. The dataset was utilized for feature extraction of CT-radiomics features and PET metabolic parameters based on volume of interest, then went through feature selection and model development with strategy of five-fold cross-validation. Specifically, model development used support vector machine, PET metabolic parameters selection used Akaike's information criterion, and CT-radiomics were reduced by the least absolute shrinkage and selection operator method then forward selection approach. The diagnostic performances of CT-radiomics, PET metabolic parameters and combination of both were illustrated by receiver operating characteristic (ROC) curves, and compared by Delong test. Five groups of selected PET metabolic parameters and CT-radiomics were counted, and potential features were found and analyzed with Mann-Whitney U test. RESULTS: The CT-radiomics, PET metabolic parameters, and combination of both among five subsets showed mean area under the curve (AUC) of 0.820 ±â€¯0.053, 0.874 ±â€¯0.081, and 0.887 ±â€¯0.046, respectively. No significant differences in ROC among models were observed through pairwise comparison in each fold (P-value from 0.09 to 0.81, Delong test). The potential features were found to be SurfaceVolumeRatio and SUVpeak (P < 0.001 of both, U test). CONCLUSION: The classification models developed by CT-radiomics features and PET metabolic parameters based on PET/CT images have substantial diagnostic capacity on lung lesions.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31701626

RESUMO

OBJECTIVE: To investigate the role of driver mechanism and the effect of electrogram dispersion-guided driver mapping and ablation in atrial fibrillation (AF) at different stages of progression. METHODS: A total of 256 consecutive patients with AF who had undergone pulmonary vein isolation (PVI) plus driver ablation or conventional ablation were divided into three groups: paroxysmal atrial fibrillation (PAF; group A, n = 51); persistent atrial fibrillation (PsAF; group B, n = 38); and long standing-persistent atrial fibrillation (LS-PsAF; group C, n = 39). PVI was performed with the guidance of the ablation index. The electrogram dispersion was analyzed for driver mapping. RESULTS: The most prominent driver regions were at roof (28.0%), posterior wall (17.6%), and bottom (21.3%). From patients with PAF to those with PsAF and LS-PsAF: the complexity of extra-pulmonary vein (PV) drivers including distribution, mean number, and area of dispersion region increased (P < .001). Patients who underwent driver ablation vs conventional ablation had higher procedural AF termination rate (76.6% vs 28.1%; P < .001). With AF progression, the termination rate gradually decreased from group A to group C, and the role of PVI in AF termination was also gradually weakened from group A to group C (39.6%, 7.4%, and 4.3%; P < .001) in patients with driver ablation. At the end of the follow-up, the rate of sinus rhythm maintenance was higher in patients with driver ablation than those with conventional ablation (89.1% vs 70.3%; P < .001). CONCLUSION: The formation of extra-PV drivers provides an important mechanism for AF maintenance with their complexity increasing with AF progression. Electrogram dispersion-guided driver ablation appears to be an efficient adjunctive approach to PVI for AF treatment.

10.
Strahlenther Onkol ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31748837

RESUMO

PURPOSE: The efficacy and tolerability of adding chemotherapy to radiotherapy in the era of intensity-modulated radiation therapy (IMRT) remain controversial among older patients with nasopharyngeal carcinoma (NPC). The present study compared IMRT alone with IMRT in combination with chemotherapy in elderly NPC patients. METHODS: Between January 2011 and December 2014, 102 patients aged >65 years with NPC who received IMRT alone (IMRT group) or IMRT in combination with chemotherapy (IMRT/CT group) were enrolled. Patients from both treatment arms were pair-matched (1:1 ratio) based on six clinical factors. Differences in overall survival (OS), disease-free survival (DFS), locoregional relapse-free survival (LRRFS), and distant metastasis-free survival (DMFS) were assessed using the Kaplan-Meier method and Cox proportional hazards models, whereas the toxicity profile was assessed using Common Terminology Criteria for Adverse Events (CTCAE) version 4. RESULTS: No significant differences were noted in OS (72.1% vs. 72.5%, p = 0.799), DFS (65.9% vs. 70.1%, p = 0.733), LRRFS (76.4% vs. 71.6%, p = 0.184), and DMFS (90.8% vs. 98.0%, p = 0.610) between the IMRT and IMRT/CT groups. Multivariate analyses showed that chemotherapy was not an independent factor for OS, DFS, LRRFS, and DMFS. However, the incidences of grade 3 vomiting/nausea (p = 0.000), leukopenia/neutropenia (p = 0.000), thrombocytopenia (p = 0.041), and anemia (p = 0.040) were significantly higher in the IMRT/CT group compared with the IMRT group. No grade 4 toxicities were observed. CONCLUSION: IMRT alone was similar to IMRT/CT in treating elderly NPC patients (age >65 years), with comparable survival outcomes and less grade 3 toxicities.

11.
J Immunother Cancer ; 7(1): 298, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31722750

RESUMO

BACKGROUND: Immunotherapy, especially immune checkpoint inhibition, has provided powerful tools against cancer. We aimed to detect the expression of common immune checkpoints and evaluate their prognostic values in nasopharyngeal carcinoma (NPC). METHODS: The expression of 9 immune checkpoints consistent with 13 features was detected in the training cohort (n = 208) by immunohistochemistry and quantified by computational pathology. Then, the LASSO cox regression model was used to construct an immune checkpoint-based signature (ICS), which was validated in a validation cohort containing 125 patients. RESULTS: High positive expression of PD-L1 and B7-H4 was observed in tumour cells (TCs), whereas PD-L1, B7-H3, B7-H4, IDO-1, VISTA, ICOS and OX40 were highly expressed in tumour-associated immune cells (TAICs). Eight of the 13 immune features were associated with patient overall survival, and an ICS classifier consisting of 5 features (B7-H3TAIC, IDO-1TAIC, VISTATAIC, ICOSTAIC, and LAG3TAIC) was established. Patients with high-risk scores in the training cohort had shorter overall (P < 0.001), disease-free (P = 0.002), and distant metastasis-free survival (P = 0.004), which were confirmed in the validation cohort. Multivariate analysis revealed that the ICS classifier was an independent prognostic factor. A combination of the ICS classifier and TNM stage had better prognostic value than the TNM stage alone. In addition, the ICS classifier was significantly associated with survivals in patients with high EBV-DNA load. CONCLUSIONS: We determined the expression status of nine immune checkpoints consistent with 13 features in NPC and further constructed an ICS prognostic model, which might add prognostic value to the TNM staging system.

12.
Biomater Sci ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31728482

RESUMO

Tumor hypoxia, as a hallmark of most solid tumors, poses a serious impediment to O2-dependent anticancer therapies, such as photodynamic therapy (PDT). Although utilizing nanocarriers to load and transport O2 to tumor tissues has been proved effective, the therapeutic outcomes have been impeded by the low O2 capacity and limited tumor penetration of the nanocarriers. To address these problems, we incorporated perfluorooctyl moieties into nanocarriers to improve the encapsulation of perfluorooctyl bromide via fluorophilic interactions, leading to elevated O2 capacity of the nanocarriers. Meanwhile, to enhance the tumor cell penetrating ability as well as reduce reticuloendothelial system recognition, the nanocarrier was further decorated with a cell-penetrating peptide, which was masked with a protecting group via an acid-labile amide bond for prolonged circulation time and acid-activated cell penetration. The in vitro study demonstrated that, apart from remarkably boosting the photocytoxicity of chlorin 6 (Ce6) at a low dosage, the rationally designed O2@DANPCe6+PFOB could even alleviate the pre-existing tumor hypoxia. After intravenous injection, O2@DANPCe6+PFOB exhibited significant tumor accumulation and retention, and potent tumor growth inhibition compared to traditional PDT. Overall, the O2@DANPCe6+PFOB mediated O2 self-supplemented PDT with tumor acidic microenviornment-activated cell penetration provides a promising strategy in anticancer treatment.

13.
Sensors (Basel) ; 19(22)2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31744258

RESUMO

Positron emission tomography (PET) imaging is an essential tool in clinical applications for the diagnosis of diseases due to its ability to acquire functional images to help differentiate between metabolic and biological activities at the molecular level. One key limiting factor in the development of efficient and accurate PET systems is the sensor technology in the PET detector. There are generally four types of sensor technologies employed: photomultiplier tubes (PMTs), avalanche photodiodes (APDs), silicon photomultipliers (SiPMs), and cadmium zinc telluride (CZT) detectors. PMTs were widely used for PET applications in the early days due to their excellent performance metrics of high gain, low noise, and fast timing. However, the fragility and bulkiness of the PMT glass tubes, high operating voltage, and sensitivity to magnetic fields ultimately limit this technology for future cost-effective and multi-modal systems. As a result, solid-state photodetectors like the APD, SiPM, and CZT detectors, and their applications for PET systems, have attracted lots of research interest, especially owing to the continual advancements in the semiconductor fabrication process. In this review, we study and discuss the operating principles, key performance parameters, and PET applications for each type of sensor technology with an emphasis on SiPM and CZT detectors-the two most promising types of sensors for future PET systems. We also present the sensor technologies used in commercially available state-of-the-art PET systems. Finally, the strengths and weaknesses of these four types of sensors are compared and the research challenges of SiPM and CZT detectors are discussed and summarized.

14.
Eur J Clin Pharmacol ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745585

RESUMO

PURPOSE: Acute nephrotoxicity is a common adverse reaction of tacrolimus therapy; however, its risk factors in pediatric nephrotic syndrome (NS) remain to be evaluated. The objective of this study was to investigate the risk factors and characteristics of tacrolimus-induced acute nephrotoxicity in children with NS. METHODS: Past records of children with NS admitted to our hospital from 2014 to 2018 were reviewed. The incidence and characteristics of nephrotoxicity were analyzed. Multivariate logistic regression analysis was used to identify the risk factors of nephrotoxicity. A clinically applicable risk score was developed and validated. RESULTS: Tacrolimus-induced nephrotoxicity occurred in 25 of 129 patients, 13 patients were grade 1, and the renal function was recovered in 22 patients. Multivariate regression analysis showed that the maximum trough concentrations (C12h) of tacrolimus (OR, 1.48; 95% CI, 1.16 to 1.88; P < 0.001), huaiqihuang granules (OR, 0.095; 95% CI, 0.014 to 0.66; P = 0.017), and diarrhea (OR, 22.00; 95% CI, 1.58 to 306.92; P = 0.022) were independently associated with tacrolimus-induced nephrotoxicity. The maximum C12h were significantly higher in patients with nephrotoxicity (median 9.0 ng/ml) and the cut-off value for acute nephrotoxicity was 6.5 ng/ml. The area under the receiver operating characteristic curve was 0.821 for the proposed model based on the observations used to create the model and 0.817 obtained from k-fold cross-validation. CONCLUSIONS: High trough concentration of tacrolimus and diarrhea can potentiate the risk of tacrolimus-induced acute nephrotoxicity in children with NS, while huaiqihuang granules can protect this condition.

15.
Chem Commun (Camb) ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746859

RESUMO

The present study reports the fabrication of a silver chalcogenolate cluster hybrid membrane (SCC membrane) through self-assembly of SCCs, and then covalent cross-linking of the modified SCC assembled materials. This strategy provides access to silver clusters with superior chemical stability and enhanced luminescence efficiency for practical applications.

16.
Age Ageing ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711096

RESUMO

BACKGROUND: post-operative delirium (POD) is a common complication in older patients, though a possible link between metabolic changes and POD development has yet to be investigated. METHODS: older patients with hip fracture who underwent hemi-arthroplasty were recruited, and delirious states were assessed for 3 days after surgery using the confusion assessment method-Chinese revision. Simultaneously, fasting blood samples were collected on the morning of surgery and on the first post-operative day. Ultimately, 244 older patients who met the inclusion and exclusion criteria were assessed. Blood samples from 60 patients with POD and 60 matched controls were analysed using metabolomics platforms. RESULTS: sixty patients (24.6%) developed POD. Principal component analysis scores plot and cross-validated scores plots from orthogonal partial least squares-discriminant analysis were implemented to visualise the differences in metabolites between the two groups before and after surgery (P < 0.05). Our data indicate that levels of ω3 and ω6 fatty acids were lower in the POD group than in the NPOD (non-POD) group both before and after surgery; tricarboxylic cycle intermediate levels were lower in the POD group than in the NPOD group, but glycolysis products were higher in the POD group than in the NPOD group after surgery. Furthermore, the branched-chain amino acid (BCAA)/aromatic amino acid ratio was lower in the POD group than in the NPOD group after surgery. CONCLUSIONS: metabolic abnormalities, including deficiencies in ω3 and ω6 fatty acids, perturbations in tricarboxylic cycle and oxidative stress and metabolic imbalances in BCAA and AAA might contribute to POD development.

17.
BMC Genomics ; 20(1): 797, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666004

RESUMO

BACKGROUND: In the pig production industry, artificial insemination (AI) plays an important role in enlarging the beneficial impact of elite boars. Understanding the genetic architecture and detecting genetic markers associated with semen traits can help in improving genetic selection for such traits and accelerate genetic progress. In this study, we utilized a weighted single-step genome-wide association study (wssGWAS) procedure to detect genetic regions and further candidate genes associated with semen traits in a Duroc boar population. Overall, the full pedigree consists of 5284 pigs (12 generations), of which 2693 boars have semen data (143,113 ejaculations) and 1733 pigs were genotyped with 50 K single nucleotide polymorphism (SNP) array. RESULTS: Results show that the most significant genetic regions (0.4 Mb windows) explained approximately 2%~ 6% of the total genetic variances for the studied traits. Totally, the identified significant windows (windows explaining more than 1% of total genetic variances) explained 28.29, 35.31, 41.98, and 20.60% of genetic variances (not phenotypic variance) for number of sperm cells, sperm motility, sperm progressive motility, and total morphological abnormalities, respectively. Several genes that have been previously reported to be associated with mammal spermiogenesis, testes functioning, and male fertility were detected and treated as candidate genes for the traits of interest: Number of sperm cells, TDRD5, QSOX1, BLK, TIMP3, THRA, CSF3, and ZPBP1; Sperm motility, PPP2R2B, NEK2, NDRG, ADAM7, SKP2, and RNASET2; Sperm progressive motility, SH2B1, BLK, LAMB1, VPS4A, SPAG9, LCN2, and DNM1; Total morphological abnormalities, GHR, SELENOP, SLC16A5, SLC9A3R1, and DNAI2. CONCLUSIONS: In conclusion, candidate genes associated with Duroc boars' semen traits, including the number of sperm cells, sperm motility, sperm progressive motility, and total morphological abnormalities, were identified using wssGWAS. KEGG and GO enrichment analysis indicate that the identified candidate genes were enriched in biological processes and functional terms may be involved into spermiogenesis, testes functioning, and male fertility.

18.
Math Biosci Eng ; 16(6): 6696-6707, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31698583

RESUMO

Microfluidic flow generation plays a fundamental role in microfluidic systems and shows potential for applications in basic biology and clinical medicine. In this study, an enabling technology is proposed to quantitatively generate microfluid flow through the automatic movement of a microsphere in liquid by using optical tweezers. A closed-loop control strategy with visual servoing feedback is introduced to achieve high precision and robustness. The theoretical solution of the generated microfluid is obtained on the basis of Stokes equations. An experimental method is proposed, and experiments are performed to verify the effectiveness of our approach. This method does not impose any dedicated fabrication of microtool, and the microfluidic flow can be dexterously adjusted by controlling the direction, speed, and distance of the microsphere from a target location. To the best of our knowledge, this is the first demonstration of optically actuating liquids through the translational movement of microspheres with closed-loop control. The proposed method will be useful in various biomedical applications needing quantitative, precise and controllable localized microfluid.

19.
Fish Physiol Biochem ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31701282

RESUMO

An 8-week feeding trial was conducted to investigate the effects of enzyme-treated soy protein (ETSP) supplementation in low protein diets on growth performance as well as flesh sensory quality and healthiness in on-growing grass carp. A total of 540 on-growing grass carp (initial average weight 325.72 ± 0.60 g) were fed six diets, which included a normal protein diet (28% crude protein) and five low protein diets (26% crude protein) supplemented with graded levels of ETSP (0.0, 0.8, 1.2, 1.6, and 2.0%). The results showed that reducing dietary protein by 2% decreased percentage weight gain, feed intake, and flesh flavor (aspartic acid, glutamic acid, histidine, and 5'-inosinic acid contents) and healthiness-related indices (linolenic acid (LA) and docosahexaenoic acid (DHA) contents and polyunsaturated fatty acids to saturated fatty acids ratio). Under the condition of reducing dietary protein by 2%, 0.8-1.2% ETSP supplementation restored above parameters to levels equal or superior to those in 28% crude protein diet group. Although reducing dietary protein by 2% did not deteriorate flesh tenderness and juiciness, 0.8-1.2% ETSP supplementation in low protein diets also improved the two indices compared with 28% crude protein diet. Moreover, ETSP-improved flesh quality was partly related to increased muscle antioxidant enzymes activities and their mRNA levels. In addition, ESTP-enhanced antioxidant enzyme mRNA levels were partly associated with the upregulation of NF-E2-related factor 2 (Nrf2) and target of rapamycin (TOR) signaling. Collectively, 0.8-1.2% ETSP supplementation in low protein diets improved growth performance as well as flesh sensory quality and healthiness in on-growing grass carp.

20.
Histol Histopathol ; : 18183, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701509

RESUMO

Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer death worldwide. Lung adenocarcinoma is the main tumor type of NSCLC. Recent advances in the molecular characterization and personalized therapies have improved NSCLC patient prognosis. Previous studies showed that protein tyrosine kinase 7 (PTK7) plays an important role in human cancers. However, the role of PTK7 has not been investigated. PTK7 expression was assessed by immunohistochemistry in 95 patients with lung adenocarcinoma. Correlations of PTK7 expression levels with clinicopathological parameters, EGFR mutation and EML4-ALK fusion were examined. Positive PTK7 expression was detected in 47.4% of lung adenocarcinoma. PTK7 expression was associated with gender (P=0.024), lymph node metastasis (P<0.001), ALK mutation (P=0.050), and EGFR mutations (P=0.014). No significant association was found between PTK7 expression and age (P=0.831), differentiation (P=0.494), adenocarcinoma subtype (P=0.098) and Ki67 (P=0.473). Our data suggest that PTK7 plays an oncogenic role in lung adenocarcinoma and may be a molecular marker for lymph node metastasis.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA