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1.
Anal Chem ; 96(5): 2227-2235, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38272489

RESUMO

Determinations of micro/nanoplastics (MNPs) in environmental samples are essential to assess the extent of their presence in the environment and their potential impact on ecosystems and human health. With the aim to provide a sensitive method with simplified pretreatment steps, cooling-assisted solid-phase microextraction (CA-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) is proposed as a new approach to quantify mass concentrations of MNPs in water and soil samples. The herein proposed CA-SPME method offers the unique advantage of integrating the thermal decomposition of MNPs and enrichment of signature compounds into one step. Poly(methyl methacrylate) (PMMA) was used as a model substance to verify the method performance in this work. Theoretical insights demonstrated that pyrolysis is the rate-determining step during the extraction process and that PMMA is effectively decomposed at 350 °C with an estimated incubation time of 13 min. Eight compounds were identified in the pyrolysis products by CA-SPME-GC-MS with the use of a DVB/CAR/PDMS coating, wherein methyl methacrylate was considered as the best indicator and dimethyl 2-methylenesuccinate was selected as the confirmation compound. Under the optimized conditions, the proposed method exhibited wide linearity (0.5-2000 µg for water and 5-1000 µg for soil) and high sensitivity, with limits of detection of 0.014 and 0.28 µg for water and soil, respectively. Finally, the proposed method was successfully applied for determinations of PMMA MNPs in real water and soil samples with satisfactory recoveries attained. The method only required the employment of a filter membrane for water analysis, while soil samples were analyzed directly without any pretreatment. The solvent-free approach, straightforward operation, and high sensitivity of the proposed method show great potential for the analysis of MNPs in different environmental samples.

2.
J Synchrotron Radiat ; 31(Pt 2): 260-267, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38252523

RESUMO

A method to optimize the thermal deformation of an indirectly cryo-cooled silicon crystal monochromator exposed to intense X-rays at a low-emittance diffraction-limited synchrotron radiation source is presented. The thermal-induced slope error of the monochromator crystal has been studied as a function of heat transfer efficiency, crystal temperature distribution and beam footprint size. A partial cooling method is proposed, which flattens the crystal surface profile within the beam footprint by modifying the cooling contact area to optimize the crystal peak temperature. The optimal temperature varies with different photon energies, which is investigated, and a proper cooling strategy is obtained to fulfil the thermal distortion requirements over the entire photon energy range. At an absorbed power up to 300 W with a maximum power density of 44.8 W mm-2 normal incidence beam from an in-vacuum undulator, the crystal thermal distortion does not exceed 0.3 µrad at 8.33 keV. This method will provide references for the monochromator design on diffraction-limited synchrotron radiation or free-electron laser light sources.

3.
J Exp Bot ; 75(3): 819-836, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37936320

RESUMO

Fruit ripening and the associated softening are major determinants of fruit quality and post-harvest shelf life. Although the mechanisms underlying fruit softening have been intensively studied, there are limited reports on the regulation of fruit softening in apples (Malus domestica). Here, we identified a zinc finger homeodomain transcription factor MdZF-HD11that trans-activates the promoter of Mdß-GAL18, which encodes a pectin-degradation enzyme associated with cell wall metabolism. Both MdZF-HD11 and Mdß-GAL18 genes were up-regulated by exogenous ethylene treatment and repressed by 1-methylcyclopropene treatment. Further experiments revealed that MdZF-HD11 binds directly to the Mdß-GAL18 promoter and up-regulates its transcription. Moreover, using transgenic apple fruit calli, we found that overexpression of Mdß-GAL18 or MdZF-HD11 significantly enhanced ß-galactosidase activity, and overexpression of MdZF-HD11 induced the expression of Mdß-GAL18. We also discovered that transient overexpression of Mdß-GAL18 or MdZF-HD11 in 'Golden Delicious' apple significantly increased the release of ethylene, reduced fruit firmness, promoted the transformation of skin color from green to yellow, and accelerated ripening and softening of the fruit. Finally, the overexpression of MdZF-HD11 in tomato also promoted fruit softening. Collectively, these results indicate that ethylene-induced MdZF-HD11 interacts with Mdß-GAL18 to promote the post-harvest softening of apple.


Assuntos
Malus , Malus/metabolismo , Frutas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Etilenos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
J Magn Reson Imaging ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777575

RESUMO

BACKGROUND: Neonates with immature auditory function (eg, weak/absent middle ear muscle reflex) could conceivably be vulnerable to noise-induced hearing loss; however, it is unclear if neonates show evidence of hearing loss following MRI acoustic noise exposure. PURPOSE: To explore the auditory effects of MRI acoustic noise in neonates. STUDY TYPE: Prospective. SUBJECTS: Two independent cohorts of neonates (N = 19 and N = 18; mean gestational-age, 38.75 ± 2.18 and 39.01 ± 1.83 weeks). FIELD STRENGTH/SEQUENCE: T1-weighted three-dimensional gradient-echo sequence, T2-weighted fast spin-echo sequence, single-shot echo-planar imaging-based diffusion-tensor imaging, single-shot echo-planar imaging-based diffusion-kurtosis imaging and T2-weighted fluid-attenuated inversion recovery sequence at 3.0 T. ASSESSMENT: All neonates wore ear protection during scan protocols lasted ~40 minutes. Equivalent sound pressure levels (SPLs) were measured for both cohorts. In cohort1, left- and right-ear auditory brainstem response (ABR) was measured before (baseline) and after (follow-up) MRI, included assessment of ABR threshold, wave I, III and V latencies and interpeak interval to determine the functional status of auditory nerve and brainstem. In cohort2, baseline and follow-up left- and right-ear distortion product otoacoustic emission (DPOAE) amplitudes were assessed at 1.2 to 7.0 kHz to determine cochlear function. STATISTICAL TEST: Wilcoxon signed-rank or paired t-tests with Bonferroni's correction were used to compare the differences between baseline and follow-up ABR and DPOAE measures. RESULTS: Equivalent SPLs ranged from 103.5 to 113.6 dBA. No significant differences between baseline and follow-up were detected in left- or right-ear ABR measures (P > 0.999, Bonferroni corrected) in cohort1, or in DPOAE levels at 1.2 to 7.0 kHz in cohort2 (all P > 0.999 Bonferroni corrected except for left-ear levels at 3.5 and 7.0 kHz with corrected P = 0.138 and P = 0.533). DATA CONCLUSION: A single 40-minute 3-T MRI with equivalent SPLs of 103.5-113.6 dBA did not result in significant transient disruption of auditory function, as measured by ABR and DPOAE, in neonates with adequate hearing protection. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 5.

5.
Eur Radiol ; 34(3): 1444-1452, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37673963

RESUMO

OBJECTIVES: Whether the alternation of the glymphatic system exists in neurodevelopmental disease still remains unclear. In this study, we investigated structural and functional changes in the glymphatic system in the treatment-naïve attention-deficit/hyperactivity disorder (ADHD) children by quantitatively measuring the Virchow-Robin spaces (VRS) volume and diffusion tensor image-analysis along the perivascular space (DTI-ALPS). METHODS: Forty-seven pediatric ADHD patients and 52 age- and gender-matched typically developing (TD) children were recruited in this prospective study. The VRS volume was calculated using a semi-automated approach in axial T2-weighted images. Diffusivities along the x-, y-, and z-axes in the projection, association, and subcortical neural fiber areas were measured. The ALPS index, a ratio that accentuated water diffusion along the perivascular space, was calculated. The Mann-Whitney U test was used to compare the quantitative parameters; Pearson's correlation was used to analyze the correlation with clinical symptoms. RESULTS: The cerebral VRS volume (mean, 15.514 mL vs. 11.702 mL) and the VRS volume ratio in the ADHD group were larger than those in the TD group (all p < 0.001). The diffusivity along the x-axis in association fiber area and ALPS index were significantly smaller in the ADHD group vs. TD group (mean, 1.40 vs.1.59, p < 0.05 after false discovery rate adjustment). Besides, the ALPS index was related to inattention symptoms of ADHD (r = - 0.323, p < 0.05). CONCLUSIONS: Our study suggests that the glymphatic system alternation may participate in the pathogenesis of ADHD, which may be a new research direction for exploring the mechanisms of psycho-behavioral developmental disorders. Moreover, the VRS volume and ALPS index could be used as the metrics for diagnosing ADHD. CLINICAL RELEVANCE STATEMENT: Considering the potential relevance of the glymphatic system for exploring the mechanisms of attention deficit/hyperactivity, the Virchow-Robin spaces volume and the analysis along the perivascular space index could be used as additional metrics for diagnosing the disorder. KEY POINTS: • Increased Virchow-Robin space volume and decreased analysis along the perivascular space index were found in the treatment-naïve attention-deficit/hyperactivity disorder children. • The results of this study indicate that the glymphatic system alternation may have a valuable role in the pathogenesis of attention-deficit/hyperactivity disorder. • The analysis along the perivascular space index is correlated with inattention symptoms of attention-deficit/hyperactivity disorder children.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Humanos , Criança , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Estudos Prospectivos , Benchmarking , Difusão , Processamento de Imagem Assistida por Computador
6.
Arch Insect Biochem Physiol ; 115(4): e22108, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572532

RESUMO

In this study, we employed high-throughput sequencing technology to determine the complete mitochondrial genomes of six ground beetles, encompassing five Harpalinae species and one Carabinae species. The sizes of mitochondrial genomes ranged from 15,334 to 16,972 bp, encompassing 37 genes, including 13 protein-coding genes, 22 transfer RNA genes, and 2 ribosomal RNA genes. Furthermore, each species was found to possess a putative control region. Combining with 65 published mitochondrial genome sequences of Carabidae as ingroups and four species from Trachypachidae, Gyrinidae and Dytiscidae as outgroups, we conducted phylogenetic analyses utilizing Maximum likelihood and Bayesian inference methods. Moreover, we reconstructed a species tree of Carabidae based on mitochondrial genome data using the coalescent-based species tree method (ASTRAL). The results revealed that the family Carabidae was not a monophyletic group. The subfamily Harpalinae was supported to be a monophyletic group in Maximum likelihood analysis. Although the subfamily Carabinae was found to be nonmonophyletic in the concatenation analyses under both Maximum likelihood and Bayesian inference criteria, it was identified as a monophyletic group in the species tree analysis.


Assuntos
Besouros , Genoma Mitocondrial , Animais , Filogenia , Besouros/genética , Teorema de Bayes
7.
Skin Res Technol ; 30(4): e13649, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38533753

RESUMO

OBJECTIVES: To establish accurate and objective dermoscopic diagnostic criteria and grading standards for males and females with androgenetic alopecia (AGA). METHODS: Twenty patients each with AGA, diffuse alopecia areata, telogen effluvium, and healthy controls were enrolled in the current study. In addition, 60 patients with grades F1/V1, F2/V2, and F3/V3 AGA (20 cases each) were enrolled. The patients underwent dermoscopic examinations. The sensitivity and specificity of the diagnostic criteria were based on the 60 AGA and 60 non-AGA. In addition, 150 patients diagnosed with AGA clinically and by dermoscopy were enrolled to calculate the accuracy of the grading criteria. RESULTS: The diagnostic criteria included primary, secondary, and exclusion criteria. The grading criteria included three indices, which divided the severity of AGA into grades 1, 2, and 3. The sensitivity and specificity of the diagnostic criteria were 98.3% and 96.7% respectively. The accuracy of grade 1, 2, and 3 dermoscopic grading criteria were 96%, 92%, and 100% respectively, with a total accuracy of 96%. LIMITATIONS: To test the diagnostic and grading criteria, more patients need to be collected. CONCLUSIONS: The dermoscopic diagnostic and grading criteria are objective with good accuracy, which could provide a reasonable basis for the early diagnosis, grading treatment, and improved prognosis for AGA.


Assuntos
Alopecia em Áreas , Dermoscopia , Masculino , Feminino , Humanos , Alopecia/terapia , Alopecia em Áreas/diagnóstico
8.
BMC Geriatr ; 24(1): 237, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448801

RESUMO

BACKGROUND: Quantitative computed tomography (QCT)-based lumbar bone mineral density (LBMD) has been used to diagnose osteoporosis. This study explored the value of lower thoracic BMD (TBMD) in diagnosing osteoporosis in older adults during CT lung cancer screening. METHODS: This study included 751 subjects who underwent QCT scans with both LBMD and TBMD. 141 of them was selected for a validation. Osteoporosis was diagnosed based on LBMD using the ACR criteria (gold standard). TBMD thresholds were obtained using receiver operating characteristic curve. TBMD was also translated into LBMD (TTBMD) and osteoporosis was defined based on TTBMD using ACR criteria. The performance of TBMD and TTBMD in identifying osteoporosis was determined by Kappa test. The associations between TBMD- and TTBMD-based osteoporosis and fracture were tested in 227 subjects with followed up status of spine fracture. RESULTS: The performance of TBMD in identifying osteoporosis was low (kappa = 0.66) if using the ACR criteria. Two thresholds of TBMD for identifying osteopenia (128 mg/cm3) and osteoporosis (91 mg/cm3) were obtained with areas under the curve of 0.97 and 0.99, respectively. The performance of the identification of osteoporosis/osteopenia using the two thresholds or TTBMD both had good agreement with the gold standard (kappa = 0.78, 0.86). Similar results were observed in validation population. Osteoporosis identified using the thresholds (adjusted hazard ratio (HR) = 18.72, 95% confidence interval (CI): 5.13-68.36) or TTBMD (adjusted HR = 10.28, 95% CI: 4.22-25.08) were also associated with fractures. CONCLUSION: Calculating the threshold of TBMD or normalizing TBMD to LBMD are both useful in identifying osteoporosis in older adults during CT lung cancer screening.


Assuntos
Doenças Ósseas Metabólicas , Fraturas Ósseas , Neoplasias Pulmonares , Osteoporose , Humanos , Idoso , Detecção Precoce de Câncer , Densidade Óssea , Neoplasias Pulmonares/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Vértebras Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X
9.
BMC Biol ; 21(1): 221, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37858148

RESUMO

BACKGROUND: Functioning as a competing endogenous RNA (ceRNA) is the main action mechanism of most cytoplasmic lncRNAs. However, it is not known whether this mechanism of action also exists in the nucleus. RESULTS: We identified four nuclear lncRNAs that are presented in granulosa cells (GCs) and were differentially expressed during sow follicular atresia. Notably, similar to cytoplasmic lncRNAs, these nuclear lncRNAs also sponge miRNAs in the nucleus of GCs through direct interactions. Furthermore, NORSF (non-coding RNA involved in sow fertility), one of the nuclear lncRNA acts as a ceRNA of miR-339. Thereby, it relieves the regulatory effect of miR-339 on CYP19A1 encoding P450arom, a rate-limiting enzyme for E2 synthesis in GCs. Interestingly, miR-339 acts as a saRNA that activates CYP19A1 transcription and enhances E2 release by GCs through altering histone modifications in the promoter by directly binding to the CYP19A1 promoter. Functionally, NORSF inhibited E2 release by GCs via the miR-339 and CYP19A1 axis. CONCLUSIONS: Our findings highlight an unappreciated mechanism of nuclear lncRNAs and show it acts as a ceRNA, which may be a common lncRNA function in the cytoplasm and nucleus. We also identified a potential endogenous saRNA for improving female fertility and treating female infertility.


Assuntos
MicroRNAs , RNA Longo não Codificante , Feminino , Suínos , Animais , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Atresia Folicular/genética , Células da Granulosa/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
10.
J Insect Sci ; 24(2)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38491951

RESUMO

The mitogenome sequence data have been widely used in inferring the phylogeny of insects. In this study, we determined the complete mitogenome for Macrotermes sp. (Termitidae, Macrotermitinae) using next-generation sequencing. Macrotermes sp. possesses a typical insect mitogenome, displaying an identical gene order and gene content to other existing termite mitogenomes. We present the first prediction of the secondary structure of ribosomal RNA genes in termites. The rRNA secondary structures of Macrotermes sp. exhibit similarities to closely related insects and also feature distinctive characteristics in their helical structures. Together with 321 published mitogenomes of termites as ingroups and 8 cockroach mitogenomes as outgroups, we compiled the most comprehensive mitogenome sequence matrix for Termitoidae to date. Phylogenetic analyses were conducted using datasets employing different data coding strategies and various inference methods. Robust relationships were recovered at the family or subfamily level, demonstrating the utility of comprehensive mitogenome sampling in resolving termite phylogenies. The results supported the monophyly of Termitoidae, and consistent relationships within this group were observed across different analyses. Mastotermitidae was consistently recovered as the sister group to all other termite families. The families Hodotermitidae, Stolotermitidae, and Archotermopsidae formed the second diverging clade, followed by the Kalotermitidae. The Neoisoptera was consistently supported with strong node support, with Stylotermitidae being sister to the remaining families. Rhinotermitidae was found to be non-monophyletic, and Serritermitidae nested within the basal clades of Rhinotermitidae and was sister to Psammotermitinae. Overall, our phylogenetic results are largely consistent with earlier mitogenome studies.


Assuntos
Baratas , Genoma Mitocondrial , Isópteros , Humanos , Animais , Filogenia , Isópteros/genética , Baratas/genética , Insetos/genética
11.
Molecules ; 29(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38398515

RESUMO

Much experimental work has been contributed to all-metal σ, π and δ-aromaticity among transition metals, semimetallics and other metals in the past two decades. Before our focused investigations on the properties of triangular and sandwich-shaped all-metal aromatics, A. I. Boldyrev presented general discussions on the concepts of all-metal σ-aromaticity and σ-antiaromaticity for metallo-clusters. Schleyer illustrated that Nucleus-Independent Chemical Shifts (NICS) were among the most authoritative criteria for aromaticity. Ugalde discussed the earlier developments of all-metal aromatic compounds with all possible shapes. Besides the theoretical predictions, many stable all-metal aromatic trinuclear clusters have been isolated as the metallic analogues of either the σ-aromatic molecule's [H3]+ ion or the π-aromatic molecule's [C3H3]+ ion. Different from Hoffman's opinion on all-metal aromaticity, triangular all-metal aromatics were found to hold great potential in applications in coordination chemistry, catalysis, and material science. Triangular all-metal aromatics, which were theoretically proved to conform to the Hückel (4n + 2) rule and possess the smallest aromatic ring, could also play roles as stable ligands during the formation of all-metal sandwiches. The triangular and sandwich-shaped all-metal aromatics have not yet been specifically summarized despite their diversity of existence, puissant developments and various interesting applications. These findings are different from the public opinion that all-metal aromatics would be limited to further applications due to their overstated difficulties in synthesis and uncertain stabilities. Our review will specifically focus on the summarization of theoretical predictions, feasible syntheses and isolations, and multiple applications of triangular and sandwich shaped all-metal aromatics. The appropriateness and necessities of this review will emphasize and disseminate their importance and applications forcefully and in a timely manner.

12.
Saudi Pharm J ; 32(1): 101919, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38178852

RESUMO

This study aimed to prepare an o/w mitiglinide microemulsion (MTGME) to improve the drug solubility and bioavailability. The formulation of o/w MTGME was optimized by the solubility study of drug, pseudo-ternary phase diagram and Box-Behnken design successively. MTGME was characterized by dynamic laser light scattering (DLS), zeta potential and transmission electron microscopy (TEM), moreover, the storage stability, pharmacodynamics and pharmacokinetics were investigated. The optimal prescription for MTGME consisted of Maisine 35-1 (oil), Cremophor EL (surfactant) and propylene glycol (PG, cosurfactant). MTGME with a spherical dimension of 58.1 ± 5.86 nm was stable when stored at 4 °C for 3 months. The blood glucose levers (BGL) of diabetic mice were uniformly and significantly decreased by intragastric (i.g.) administration of 1-4 mg/kg MTGME, in which BGL (i.g. 4 mg/kg MTGME) was reduced by 69% during 24 h. The pharmacokinetics study of MTGME (i.g., 20 mg/kg) in Wistar rats showed higher plasma drug concentration (Cmax, 2.9 folds), larger area under curve (AUC, 4.6 folds) and oral bioavailability than those of MTG suspensions. Generally, the MTGME (o/w) showed good effect on controlling hyperglycemia. Therefore, microemulsion can be used as an effective oral drug delivery system to improve the bioavailability of MTG.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38546159

RESUMO

BACKGROUND: Acceptance and commitment therapy (ACT) is a psychotherapy technique, which promotes psychological flexibility and enables patients to change behaviors based on value-directed goals. However, the beneficial effects of ACT on glycemic control, self-care behaviors, acceptance of diabetes, self-efficacy, and psychological burden are still unclear among patients with type 2 diabetes mellitus (T2DM). AIMS: This study aimed to systematically synthesize scientific evidence to determine the effectiveness of ACT among patients with T2DM on glycemic control, self-care behaviors, acceptance of diabetes, self-efficacy, and psychological burden and identify the optimal characteristics of effective interventions. METHODS: Nine electronic databases were searched to identify eligible studies of randomized controlled trials from inception to June 2023. Two reviewers independently assessed the study eligibility, extracted the data, and performed the quality appraisal using the Cochrane Risk of Bias 2 Tool. The meta-analysis was conducted using Review Manager 5.3. The certainty of the evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation system. RESULTS: Ten studies involving 712 participants were included. ACT demonstrated significant improvements on patients' glycemic control (mean difference [MD]: 0.95%; p < .001), self-care behaviors (MD: 1.86; p = .03), diabetes acceptance (MD: 7.80; p < .001), self-efficacy (standardized mean difference [SMD]: 1.04; p < .001), anxiety (SMD: -1.15; p = .006), and depression (SMD: -1.10; p = .04). However, favorable but nonsignificant improvements were found in diabetes distress. Subgroup analyses demonstrated that ACT offered more than five sessions using individualized format, with theoretical underpinnings and professional input from multidisciplinary therapists are recommended to yield better results on glycemic control and self-care behaviors. LINKING EVIDENCE TO ACTION: Acceptance and commitment therapy could generate beneficial effectiveness on glycemic control, self-care behaviors, acceptance of diabetes, self-efficacy, anxiety, and depression among patients with T2DM. Large-scale trials with rigorous design and representative samples are warranted to strengthen the current evidence.

14.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2468-2477, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38812146

RESUMO

In order to characterize and identify the chemical components in different parts of Artemisia argyi(roots, stems, leaves, and seeds), compounds with antioxidant activity were screened. In this study, ultra-performance liquid chromatography-2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt-quadrupole time-of-flight-tandem mass spectrometry(UPLC-ABTS-Q-TOF-MS) was used as an online combination technique. Poroshell 120 SB-Aq(3.0 mm×150 mm, 2.7 µm) was used as the column, and acetonitrile(A)-0.2% formic acid water(B) was adopted as the mobile phase to perform gradient elution and was scanned in positive and negative ion modes. MassLynx software was utilized, and combined with reference substances and related literature, the chemical components of different parts of A. argyi were identified and compared. The antioxidant active components were detected by using the online detection system, and the antioxidant activities of active components of different parts of A. argyi were compared and evaluated by scavenging efficiency. As a result, a total of 87 compounds were identified from extracts of different parts of A. argyi, and 38, 72, 85, and 33 components were identified from roots, stems, leaves, and seeds. 22 compounds with antioxidant activity were screened, and 14, 17, 20, and 11 compounds with antioxidant activity were identified from roots, stems, leaves, and seeds. The results show that there are certain differences in chemical components and antioxidant components of different parts of A. argyi, which provides data support for the resource utilization and further research and development of A. argyi.


Assuntos
Antioxidantes , Artemisia , Artemisia/química , Antioxidantes/química , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Medicamentos de Ervas Chinesas/química , Folhas de Planta/química , Espectrometria de Massas/métodos , Ácidos Sulfônicos/química , Sementes/química , Benzotiazóis/química , Raízes de Plantas/química
15.
BMC Genomics ; 24(1): 158, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991328

RESUMO

BACKGROUND: Ammonium (NH4+) is a key nitrogen source supporting plant growth and development. Proteins in the ammonium transporter (AMT) family mediate the movement of NH4+ across the cell membrane. Although several studies have examined AMT genes in various plant species, few studies of the AMT gene family have been conducted in chili pepper. RESULTS: Here, a total of eight AMT genes were identified in chili pepper, and their exon/intron structures, phylogenetic relationships, and expression patterns in response to arbuscular mycorrhizal (AM) colonization were explored. Synteny analyses among chili pepper, tomato, eggplant, soybean, and Medicago revealed that the CaAMT2;1, CaAMT2.4, and CaAMT3;1 have undergone an expansion prior to the divergence of Solanaceae and Leguminosae. The expression of six AMT2 genes was either up-regulated or down-regulated in response to AM colonization. The expression of CaAMT2;1/2;2/2;3 and SlAMT2;1/2;2/2;3 was significantly up-regulated in AM fungi-inoculated roots. A 1,112-bp CaAMT2;1 promoter fragment and a 1,400-bp CaAMT2;2 promoter fragment drove the expression of the ß-glucuronidase gene in the cortex of AM roots. Evaluation of AM colonization under different NH4+ concentrations revealed that a sufficient, but not excessive, supply of NH4+ promotes the growth of chili pepper and the colonization of AM. Furthermore, we demonstrated that CaAMT2;2 overexpression could mediate NH4+ uptake in tomato plants. CONCLUSION: In sum, our results provide new insights into the evolutionary relationships and functional divergence of chili pepper AMT genes. We also identified putative AMT genes expressed in AM symbiotic roots.


Assuntos
Compostos de Amônio , Capsicum , Micorrizas , Micorrizas/metabolismo , Capsicum/genética , Capsicum/metabolismo , Simbiose/fisiologia , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Proteínas de Membrana Transportadoras/genética , Regulação da Expressão Gênica de Plantas
16.
Plant Biotechnol J ; 21(7): 1465-1478, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37069831

RESUMO

Existing CRISPR/Cas12a-based diagnostic platforms offer accurate and vigorous monitoring of nucleic acid targets, but have the potential to be further optimized for more efficient detection. Here, we profiled 16 Cas12a orthologs, focusing on their trans-cleavage activity and their potential as diagnostic enzymes. We observed the Mb2Cas12a has more robust trans-cleavage activity than other orthologs, especially at lower temperatures. An engineered Mb2Cas12a-RRVRR variant presented robust trans-cleavage activity and looser PAM constraints. Moreover, we found the existing one-pot assay, which simultaneously performed Recombinase Polymerase Amplification (RPA) and Cas12a reaction in one system, resulted in the loss of single-base discrimination during diagnosis. Therefore, we designed a reaction vessel that physically separated the RPA and Cas12a steps while maintaining a closed system. This isolated but closed system made diagnostics more sensitive and specific and effectively prevented contamination. This shelved Mb2Cas12a-RRVRR variant-mediated assay detected various targets in less than 15 min and exhibited equal or greater sensitivity than qPCR when detecting bacterial pathogens, plant RNA viruses and genetically modified crops. Overall, our findings further improved the efficiency of the current CRISPR-based diagnostic system and undoubtedly have great potential for highly sensitive and specific detection of multiple sample types.


Assuntos
Ácidos Nucleicos , Produtos Agrícolas , Plantas Geneticamente Modificadas , RNA de Plantas , Recombinases/genética , Sistemas CRISPR-Cas/genética
17.
J Virol ; 96(14): e0043822, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35758667

RESUMO

In this study, we assessed the potential synergistic effect of the Erns RNase activity and the poly-U insertion in the 3' untranslated region (UTR) of the low-virulence classical swine fever virus (CSFV) isolate Pinar de Rio (PdR) in innate and adaptive immunity regulation and its relationship with classical swine fever (CSF) pathogenesis in pigs. We knocked out the Erns RNase activity of PdR and replaced the long polyuridine sequence of the 3' UTR with 5 uridines found typically at this position, resulting in a double mutant, vPdR-H30K-5U. This mutant induced severe CSF in 5-day-old piglets and 3-week-old pigs, with higher lethality in the newborn (89.5%) than in the older (33.3%) pigs. However, the viremia and viral excretion were surprisingly low, while the virus load was high in the tonsils. Only alpha interferon (IFN-α) and interleukin 12 (IL-12) were highly and consistently elevated in the two groups. Additionally, high IL-8 levels were found in the newborn but not in the older pigs. This points toward a role of these cytokines in the CSF outcome, with age-related differences. The disproportional activation of innate immunity might limit systemic viral spread from the tonsils and increase virus clearance, inducing strong cytokine-mediated symptoms. Infection with vPdR-H30K-5U resulted in poor neutralizing antibody responses compared with results obtained previously with the parent and RNase knockout PdR. This study shows for the first time the synergistic effect of the 3' UTR and the Erns RNase function in regulating innate immunity against CSFV, favoring virus replication in target tissue and thus contributing to disease severity. IMPORTANCE CSF is one of the most relevant viral epizootic diseases of swine, with high economic and sanitary impact. Systematic stamping out of infected herds with and without vaccination has permitted regional virus eradication. However, the causative agent, CSFV, persists in certain areas of the world, leading to disease reemergence. Nowadays, low- and moderate-virulence strains that could induce unapparent CSF forms are prevalent, posing a challenge for disease eradication. Here, we show for the first time the synergistic role of lacking the Erns RNase activity and the 3' UTR polyuridine insertion from a low-virulence CSFV isolate in innate immunity disproportional activation. This might limit systemic viral spread to the tonsils and increase virus clearance, inducing strong cytokine-mediated symptoms, thus contributing to disease severity. These results highlight the role played by the Erns RNase activity and the 3' UTR in CSFV pathogenesis, providing new perspectives for novel diagnostic tools and vaccine strategies.


Assuntos
Vírus da Febre Suína Clássica , Peste Suína Clássica , Síndrome da Liberação de Citocina , Regiões 3' não Traduzidas/genética , Imunidade Adaptativa/genética , Animais , Peste Suína Clássica/imunologia , Peste Suína Clássica/patologia , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/enzimologia , Vírus da Febre Suína Clássica/genética , Vírus da Febre Suína Clássica/imunologia , Vírus da Febre Suína Clássica/patogenicidade , Síndrome da Liberação de Citocina/genética , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/virologia , Citocinas , Imunidade Inata/genética , Interferon-alfa/imunologia , Interleucina-12/imunologia , Ribonucleases/genética , Ribonucleases/metabolismo , Suínos , Vacinas Virais , Virulência/genética
18.
Mol Cell Biochem ; 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38129625

RESUMO

Polypyrimidine tract-binding protein 1 (PTBP1) is a member of the heterogeneous nuclear ribonucleoprotein (hnRNP) family, which plays a key role in alternative splicing of precursor mRNA and RNA metabolism. PTBP1 is universally expressed in various tissues and binds to multiple downstream transcripts to interfere with physiological and pathological processes such as the tumor growth, body metabolism, cardiovascular homeostasis, and central nervous system damage, showing great prospects in many fields. The function of PTBP1 involves the regulation and interaction of various upstream molecules, including circular RNAs (circRNAs), microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). These regulatory systems are inseparable from the development and treatment of diseases. Here, we review the latest knowledge regarding the structure and molecular functions of PTBP1 and summarize its functions and mechanisms of PTBP1 in various diseases, including controversial studies. Furthermore, we recommend future studies on PTBP1 and discuss the prospects of targeting PTBP1 in new clinical therapeutic approaches.

19.
Ann Bot ; 131(4): 655-666, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-36694346

RESUMO

BACKGROUND AND AIMS: Polyploidization can improve plant mass yield for bioenergy support, yet few studies have investigated ozone (O3) sensitivity linked to internal regulatory mechanisms at different ploidy levels. METHODS: Diploid and triploid Populus tomentosa plants were exposed to ambient and ambient plus 60 ppb [O3]. We explored their differences in sensitivity (leaf morphological, physiological and biochemical traits, and plant mass) as well as mechanisms of avoidance (stomatal conductance, xanthophyll cycle, thermal dissipation) and tolerance (ROS scavenging system) in response to O3 at two developmental phases. KEY RESULTS: Triploid plants had the highest plant growth under ambient O3, even under O3 fumigation. However, triploid plants were the most sensitive to O3 and under elevated O3 showed the largest decreases in photosynthetic capacity and performance, as well as increased shoot:root ratio, and the highest lipid peroxidation. Thus, plant mass production could be impacted in triploid plants under long-term O3 contamination. Both diploid and triploid plants reduced stomatal aperture in response to O3, thereby reducing O3 entrance, yet only in diploid plants was reduced stomatal aperture associated with minimal (non-significant) damage to photosynthetic pigments and lower lipid peroxidation. CONCLUSIONS: Tolerance mechanisms of plants of both ploidy levels mainly focused on the enzymatic reduction of hydrogen peroxide through catalase and peroxidase, yet these homeostatic regulatory mechanisms were higher in diploid plants. Our study recommends triploid white poplar as a bioenergy species only under short-term O3 contamination. Under continuously elevated O3 over the long term, diploid white poplar may perform better.


Assuntos
Ozônio , Populus , Ozônio/farmacologia , Populus/genética , Triploidia , Fotossíntese/fisiologia , Folhas de Planta/genética , Ploidias
20.
Biometrics ; 79(1): 178-189, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34608993

RESUMO

In this paper, we propose a frequentist model averaging method for quantile regression with high-dimensional covariates. Although research on these subjects has proliferated as separate approaches, no study has considered them in conjunction. Our method entails reducing the covariate dimensions through ranking the covariates based on marginal quantile utilities. The second step of our method implements model averaging on the models containing the covariates that survive the screening of the first step. We use a delete-one cross-validation method to select the model weights, and prove that the resultant estimator possesses an optimal asymptotic property uniformly over any compact (0,1) subset of the quantile indices. Our proof, which relies on empirical process theory, is arguably more challenging than proofs of similar results in other contexts owing to the high-dimensional nature of the problem and our relaxation of the conventional assumption of the weights summing to one. Our investigation of finite-sample performance demonstrates that the proposed method exhibits very favorable properties compared to the least absolute shrinkage and selection operator (LASSO) and smoothly clipped absolute deviation (SCAD) penalized regression methods. The method is applied to a microarray gene expression data set.


Assuntos
Projetos de Pesquisa , Humanos , Simulação por Computador , Análise de Regressão
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