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1.
Microb Pathog ; 192: 106709, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38810766

RESUMEN

This study prepared a novel monoclonal antibody (MAb) against mink enteritis parvovirus (MEV) and identified its antigen epitope. The antibody subclass is identified as IgG1, the titers of the MAb is up to 1:1 × 106 and keeps stably after low-temperature storage for 9 months or 11 passages of the MAb cells. The MAb can specifically recognize MEV in the cells in IFA, but not Aleutian disease virus (ADV) or canine distemper virus (CDV). Its antigen epitope was identified as a polypeptide containing 5 key amino acids (378YAFGR382) and the homology in 20 MEV strains, 4 canine parvovirus strains, and 4 feline panleukopenia virus strains was 100%. This study supplies a biological material for developing new methods to detect MEV.


Asunto(s)
Anticuerpos Monoclonales , Anticuerpos Antivirales , Virus del Moquillo Canino , Epítopos , Virus de la Enteritis del Visón , Animales , Anticuerpos Monoclonales/inmunología , Epítopos/inmunología , Virus de la Enteritis del Visón/inmunología , Virus del Moquillo Canino/inmunología , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Visón/inmunología , Inmunoglobulina G/inmunología , Virus de la Enfermedad Aleutiana del Visón/inmunología , Parvovirus Canino/inmunología , Virus de la Panleucopenia Felina/inmunología , Mapeo Epitopo , Ratones , Ratones Endogámicos BALB C , Enteritis Viral del Visón/inmunología
2.
Sensors (Basel) ; 23(18)2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37765906

RESUMEN

Circular synthetic aperture radar (CSAR) can obtain higher image resolution and more target information using 360° observation of the target. Due to the anisotropy of target scattering characteristics in the actual scene, the sub-aperture imaging method is usually used for CSAR imaging. However, the uniformly divided overlapping sub-aperture CSAR imaging algorithm only considers phase compensation, ignoring the effect of target scattering characteristics on echo amplitude. In CSAR imaging scenarios carried by small rotor unmanned aerial vehicles (SRUAVs), the size of the observed scene cannot be ignored compared to the distance between the target and the antenna and the effect of the anisotropy of the target scattered energy on the echo amplitude should be considered. In this paper, a sub-aperture CSAR imaging method based on adaptive overlapping sub-aperture is proposed. First, the boundary points of the sub-aperture are determined by analyzing the correlation coefficient and the variation coefficient of the energy function. Next, the overlapping sub-aperture division schemes are automatically generated by screening and combining the boundary points. The sub-aperture images are then generated by a Back Projection (BP) algorithm. Finally, sub-aperture image registration and incoherent superposition are used to generate the final CSAR image. Verified by the CSAR field echo data, the proposed method can realize imaging of the original echo data without the Inertial Navigation System (INS) and Global Positioning System (GPS) observation data. Compared with the CSAR full-aperture BP imaging algorithm, the entropy of the image generated by the proposed method increased by 66.77%. Compared with the sub-aperture CSAR imaging algorithm, the entropy of the image generated by the proposed method was improved by 11.12%, retaining more details of the target, improving the target contour features, and enhancing the focusing effect.

3.
Front Psychol ; 14: 1160681, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37251052

RESUMEN

Introduction: Given the significant role of work engagement of teachers in educational contexts, some scholarly attention has been directed to exploring the predictors of this construct. Against this backdrop, this study aimed to investigate the predictors of teacher work engagement among Chinese English as a foreign language (EFL) teachers by testing a model that includes teacher self-efficacy, teacher reflection, and teacher resilience. Methods: To achieve this goal, 512 EFL teachers were invited to participate in an online survey, which consisted of four questionnaires. The construct validity of the measures was confirmed through confirmatory factor analysis. Then, structural equation modeling was utilized to examine the relationships between the variables. Results: The findings indicated that teacher self-efficacy, teacher reflection, and teacher resilience were direct predictors of work engagement, and teacher self-efficacy had an indirect effect on work engagement via teacher reflection and resilience. Similarly, teacher reflection also had an indirect impact on work engagement through teacher resilience. Discussion: These results have important implications for teacher education programs. The significance of these predictors of work engagement among EFL teachers highlights the importance of fostering self-efficacy, reflection, and resilience among teachers in order to promote their work engagement. Further research can explore ways to enhance these predictors through training and support programs for teachers.

4.
Oncol Lett ; 20(4): 50, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32802170

RESUMEN

Several previous studies have shown that mutations in B-Raf proto-oncogene (BRAF) and telomerase reverse transcriptase (TERT) can be used for the diagnosis and prognosis of papillary thyroid carcinoma (PTC). However, whether mutations in BRAF and the TERT promoter may improve the accurate identification and risk stratification of high-risk patients in the early stage of PTC remains unclear and requires further investigation. In the present study, mutations in BRAF and the TERT promoter were examined in 205 patients using PCR and Sanger DNA sequencing. The potential association between mutations in these two genes and the clinicopathological characteristics of patients with PTC was then analyzed. BRAF mutations were identified in 169/205 (82.4%) patients, whereas only 8/205 (3.9%) patients presented mutations in the TERT promoter, seven patients exhibited a C228T mutation, and the remaining one had a C250T mutation. There were 6/205 (2.9%) patients with mutations in both BRAF and the TERT promoter. Importantly, compared with patients with no mutations, patients with mutations in BRAF were more likely to exhibit mutations in the TERT promoter. A significant difference in lymph node metastasis was found between the BRAF V600E mutation group and the group without mutations in BRAF. Mutations in the TERT promoter were significantly correlated with older age, extrathyroidal invasion, tumor multifocality and advanced tumor/node/metastasis stage, which are associated with the aggressiveness of PTC. Moreover, compared with patients exhibiting mutations in BRAF, mutations in the TERT promoter were found to be significantly associated with aggressive clinicopathological features and higher risk of recurrence or distant metastasis. Collectively, mutations in the TERT promoter were not frequent, but were significantly correlated with more aggressive clinicopathological features of PTC. Therefore, mutations in the TERT promoter may be an important factor in the genetic background of PTC, and detection of such mutations may help the accurate identification and management of high-risk patients with recurrent or distant metastasis.

5.
Insect Biochem Mol Biol ; 123: 103406, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32485215

RESUMEN

Vitellogenin (Vg) is important for insect egg maturation and embryo development. In the present study, we characterized the molecular structure and expression profile of Vg gene, and analyzed its reproductive functions in diamondback moth, Plutella xylostella (L.), a destructive pest of cruciferous crops, using CRISPR/Cas9 system. The P. xylostella Vg (PxVg) included all conserved domains and motifs that were commonly found in most insect Vgs except for the polyserine tract. PxVg gene was highly expressed in female pupae and adults. PxVg protein was detected in eggs and female adults. PxVg was mainly expressed in the fat body and its protein was detected in most tissues, except in the midgut. CRISPR/Cas9-induced PxVg knockout successfully constructed a homozygous mutant strain with a 5-base pair nucleotide deletion. No PxVg protein was found in the mutant individuals and in their ovaries. There were no significant differences between wild (WT) and mutant (Mut-5) types of P. xylostella in terms of ovariole length and the number of fully developed oocytes in newly emerged females. No significant difference was observed in the number of eggs laid within two days, but there was a lower egg hatchability (84% for WT vs. 47% for Mut-5). This is the first study presenting the functions of Vg in ovary development, egg maturation, oviposition and embryonic development of P. xylostella. Our results suggest that the reproductive functions of Vg may be species-specific in insects. It is possible that Vg may not be the major egg yolk protein precursor in P. xylostella. Other "functional Vgs" closely involved in the yolk formation and oogenesis would need to be further explored in P. xylostella.


Asunto(s)
Mariposas Nocturnas , Vitelogeninas , Animales , Proteína 9 Asociada a CRISPR , Sistemas CRISPR-Cas , Desarrollo Embrionario/genética , Técnicas de Inactivación de Genes , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Larva/metabolismo , Mariposas Nocturnas/embriología , Mariposas Nocturnas/genética , Oogénesis/genética , Oviposición , Control de Plagas/métodos , Transcriptoma , Vitelogeninas/genética , Vitelogeninas/metabolismo
6.
Mol Cytogenet ; 13: 13, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32308740

RESUMEN

BACKGROUND: Chromosomal rearrangements in addition to t(15;17) have been reported in 25-40% of APL patients, with a large predominance of trisomy 8. Other abnormalities are far less frequent, particularly as ider(17), and the prognostic significance is still unclear. CASE PRESENTATION: We present the case of a patient with t(15;17)(q22;q21), der(15)t(15;17) and ider(17)(q10)t(15;17)(q22;q21). In particular, the RT-PCR result for PML-RARA of this patient was a false negative and mutational analysis of AML-related genes showed SNP rs2454206 in the TET2 gene and yielded negative findings in other genes including AML1, ASXL1, CEBPA, DNMT3A, FLT3, KIT, NPM1, TP53, and U2AF1. After the early usage of arsenic trioxide combinated with ATRA and vigorous supportive treatment to maintain PLT ≥30×109/L and FIB >1500 mg/L, this patient was under MMR and HCR without any clinical symptoms or signs until now. CONCLUSION: False negative reslults of RT-PCR analysis for PML-RARA are rare in APL and ider(17) is even more infrequent. To our knowledge, this is the first reported case of APL with ider(17) and false negative RT-PCR analysis results. The role of ider(17) in APL is still an ongoing investigation and limited by the small number of published cases. The patient reported here benefited from vigorous supportive treatment during the combination of ATRA and arsenic trioxide in induction chemotherapy and the clinical outcome was favorable.

7.
Front Physiol ; 10: 1120, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31555150

RESUMEN

Ecdysteroids play an essential role in controlling insect development and reproduction. Their pathway is regulated by a group of enzymes called Halloween gene proteins. The relationship between the Halloween genes and ecdysteroid synthesis has yet to be clearly understood in diamondback moth, Plutella xylostella (L.), a worldwide Lepidoptera pest attacking cruciferous crops and wild plants. In this study, complete sequences for six Halloween genes, neverland (nvd), shroud (sro), spook (spo), phantom (phm), disembodied (dib), shadow (sad), and shade (shd), were identified. Phylogenetic analysis revealed a strong conservation in insects, including Halloween genes of P. xylostella that was clustered with all other Lepidoptera species. Three Halloween genes, dib, sad, and shd were highly expressed in the adult stage, while nvd and spo were highly expressed in the egg and pupal stages, respectively. Five Halloween genes were highly expressed specifically in the prothorax, which is the major site of ecdysone production. However, shd was expressed predominantly in the fat body to convert ecdysone into 20-hydroxyecdysone. RNAi-based knockdown of sad, which is involved in the last step of ecdysone biosynthesis, significantly reduced the 20E titer and resulted in a longer developmental duration and lower pupation of fourth-instar larvae, as well as caused shorter ovarioles and fewer fully developed eggs of P. xylostella. Furthermore, after the knockdown of sad, the expression levels of Vg and VgR genes were significantly decreased by 77.1 and 53.0%. Meanwhile, the number of eggs laid after 3 days was significantly reduced in sad knockdown females. These results suggest that Halloween genes may play a critical role in the biosynthesis of ecdysteroids and be involved in the development and reproduction of P. xylostella. Our work provides a solid basis for understanding the functional importance of these genes, which will help to screening potential genes for pest management of P. xylostella.

8.
Front Physiol ; 10: 1585, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32038281

RESUMEN

The vitellogenin receptor (VgR) belongs to the low-density lipoprotein receptor (LDLR) gene superfamily and plays an indispensable role in Vg transport, yolk deposition, and oocyte development. For this reason, it has become a promising target for pest control. The involvement of VgR in Vg transport and reproductive functions remains unclear in diamondback moths, Plutella xylostella (L.), a destructive pest of cruciferous crops. Here, we cloned and identified the complete cDNA sequence of P. xylostella VgR, which encoded 1805 amino acid residues and contained four conserved domains of LDLR superfamily. PxVgR was mainly expressed in female adults, more specifically in the ovary. PxVgR protein also showed the similar expression profile with the PxVgR transcript. CRISPR/Cas9-mediated PxVgR knockout created a homozygous mutant of P. xylostella with 5-bp-nucleotide deletion in the PxVgR. The expression deficiency of PxVgR protein was detected in the ovaries and eggs of mutant individuals. Vg protein was still detected in the eggs of the mutant individuals, but with a decreased expression level. However, PxVg transcripts were not significantly affected by the PxVgR knockout. Knockout of PxVgR resulted in shorter ovarioles of newly emerged females. No significant difference was detected between wild and mutant individuals in terms of the number of eggs laid in the first 3 days after mating. The loss of PxVgR gene resulted in smaller and whiter eggs and lower egg hatching rate. This study represents the first report on the functions of VgR in Vg transport, ovary development, oviposition, and embryonic development of P. xylostella using CRISPR/Cas9 technology. This study lays the foundation for understanding molecular mechanisms of P. xylostella reproduction, and for making use of VgR as a potential genetic-based molecular target for better control of the P. xylostella.

9.
Exp Biol Med (Maywood) ; 241(11): 1186-94, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26846977

RESUMEN

Varying degrees of renal injury could lead to different changes in urinary protein composition. We want to find urinary candidate peptide biomarkers in type 2 diabetic patients with different extents of kidney injury. Two sets of patients were recruited. Discovery set: weak cationic-exchange magnetic beads coupled with matrix-assisted laser desorption ionization time-of-flight mass spectrometry were used to profile the low-molecular weight peptidome in urine samples from type 2 diabetes patients with normoalbuminura and microalbuminuria. The differently expressed urinary peptides were screened by ClinProTools2.1 bioinformatics software and identified through nano-liquid chromatography-tandem mass spectrometry. Verification set: the above screened urinary peptides were validated by use matrix-assisted laser desorption ionization time-of-flight mass spectrometry on another group of type 2 diabetes patients with different extents use of kidney injury. In the screening and identification stages, seven urinary peptides were selected as the most promising biomarker candidates, and they were identified as fragments of vitronectin precursor, isoform 1 of fibrinogen alpha chain precursor, prothrombin precursor and inter-alpha-trypsin inhibitor heavy chain H4. The diagnostic efficacy of these urinary peptides was evaluated by area under the receiver operating characteristic curve, and they were 0.767, 0.768, 0.868, 0.910, 0.860, 0.843, and 0.865, respectively. In the verification stage, m/z 1743.9, 2154, 2175.5, and 2184.9 were decreased as albumin-to-creatinine (Alb/Cre) increased and m/z 2231.1, 2430.8, and 2756.1 were elevated as Alb/Cre rose. These small molecule peptides are related to type 2 diabetes kidney damage, and they may play an important role in monitoring type 2 diabetes.


Asunto(s)
Biomarcadores/orina , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/patología , Proteinuria/patología , Proteoma/análisis , Orina/química , Cromatografía Liquida , Humanos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem
10.
Ann Clin Lab Sci ; 45(3): 264-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26116589

RESUMEN

OBJECTIVE: We aim to explore and identify the high abundance of peptides in urine. METHODS: Random urine samples from 30 healthy individuals were purified by weak cationic-exchange magnetic beads (MB-WCX) and then analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Then the generated mass spectra of peptides were handled by ClinPro-Tools2.1 bioinformatics software and the high abundance of urinary peptide was filtered. Subsequently, the amino acid sequences of highly expressed peptides were identified by a nano-liquid chromatography-tandem mass spectrometry and the corresponding protein names were found by Sequest search. RESULTS: There were 159 urinary peptides of which mass to charge ratios (m/z) varied between 1,000 and 10,000 in the 30 healthy samples. Only peaks with average intensity >600 and the frequency >50% in the whole group were filtered. There were 15 peptides passed though the threshold and they were identified as fragments of fibrinogen alpha chain precursor, vitronectin precursor, inter-alpha-trypsin inhibitor heavy chain H4, complement component 3, prothrombin, apolipoprotein C-II, and alpha-fetoprotein. CONCLUSION: These urinary peptides could be used for further research on urine.


Asunto(s)
Tamizaje Masivo , Péptidos/orina , Adulto , Anciano , Secuencia de Aminoácidos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Péptidos/química , Proteómica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
11.
Int J Endocrinol ; 2015: 758402, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26089891

RESUMEN

Objectives. We aim to explore urinary biomarkers that could monitor CAD in type 2 diabetic patients. Materials and Methods. Urine samples from two groups, twenty-eight type 2 diabetic patients with coexisting CAD and thirty type 2 diabetic patients without CAD, were purified by MB-WCX and then analyzed by MALDI-TOF-MS. Subsequently, we compared the urinary peptide signatures of the two groups by use of ClinProTools2.1 and evaluated the potential ability of the differently expressed peptides to distinguish type 2 diabetic patients with coexisting CAD from type 2 diabetic patients without CAD by ROC analysis. Finally, the differently expressed peptides were identified by nanoliquid chromatography-tandem mass spectrometry. Results. There were six differently expressed peptides (m/z 1305.2, 1743.9, 2184.9, 2756.1, 3223.2, and 6196.1) between the two groups of subjects, and they were identified as fragments of isoform 1 of fibrinogen alpha chain precursor, prothrombin precursor, and interalpha-trypsin inhibitor heavy chain H4. The diagnostic efficacy of m/z 2756.1 and m/z 3223.2 was better than the other peptides. Area under ROC of the m/z 2756.1, and m/z 3223.2 was 0.98 and 0.93, respectively. Conclusions. These urinary peptides are potential urinary biomarkers for monitoring of type 2 diabetic patients with CAD.

12.
Diabetes Res Clin Pract ; 101(2): 187-93, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23769013

RESUMEN

AIMS: To seek urinary peptides as biomarkers distinguishing type 2 diabetes mellitus (T2DM) patients from healthy controls. METHODS: Random urine samples obtained from 28 patients with T2DM and 29 healthy individuals were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) after purification using weak cationic-exchange magnetic beads (MB-WCX). Then the generated mass spectra of peptides were analyzed by ClinProTools2.1 bioinformatics software. Subsequently, the amino acid sequences of differently expressed peptides were identified by a nano-liquid chromatography-tandem mass spectrometry and a Sequest search found the corresponding protein name. RESULTS: Three differently expressed peptides and their mass to charge ratios (m/z) were found. Compared with healthy controls, the peak areas of the three differently expressed peptides were all reduced in T2DM, and the m/z were 1056.1 (m/z), 1963.5 (m/z), 2123.5 (m/z), respectively. The above-mentioned peptides were further identified as fragments of histidine triad nucleotide-binding protein 1 (HINT1), bifunctional aminoacyl-tRNA synthetase (EPRS), and clusterin precursor protein (CLU). CONCLUSIONS: Histidine triad nucleotide-binding protein 1, bifunctional aminoacyl-tRNA synthetase, and clusterin precursor protein may serve as potential biomarkers distinguishing type 2 diabetes mellitus patients from healthy controls.


Asunto(s)
Biomarcadores/orina , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/orina , Proteómica/métodos , Adulto , Aminoacil-ARNt Sintetasas/orina , Clusterina/orina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/orina , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
13.
Science ; 328(5980): 882-4, 2010 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-20466928

RESUMEN

Direct studies of how organic molecules diffuse on metal oxide surfaces can provide insights into catalysis and molecular assembly processes. We studied individual catechol molecules, C6H4(OH)2, on a rutile TiO2(110) surface with scanning tunneling microscopy. Surface hydroxyls enhanced the diffusivity of adsorbed catecholates. The capture and release of a proton caused individual molecules to switch between mobile and immobile states within a measurement period of minutes. Density functional theory calculations showed that the transfer of hydrogen from surface hydroxyls to the molecule and its interaction with surface hydroxyls substantially lowered the activation barrier for rotational motion across the surface. Hydrogen bonding can play an essential role in the initial stages of the dynamics of molecular assembly.

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