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1.
Appl Microbiol Biotechnol ; 108(1): 298, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38607493

RESUMEN

Radopholus similis is a destructive, migratory, and endophytoparasitic nematode. It has two morphologically indistinguishable pathotypes (or physiological races): banana and citrus pathotypes. At present, the only reliable method to differentiate the two pathotypes is testing the infestation and parasitism of nematodes on Citrus spp. via inoculation. However, differences in inoculation methods and conditions adopted by different researchers complicate obtaining consistent results. In this study, the parasitism and pathogenicity of 10 R. similis populations on rough lemon (Citrus limon) seedlings and the tropism and invasion of rough lemon roots were tested. It revealed that populations SWK, GJ, FZ, GZ, DBSR, and YJ were citrus pathotypes, which showed parasitism and pathogenicity on rough lemon and could invade rough lemon roots, whereas populations XIN, ML, HN6, and HL were banana pathotypes, having no parasitism and pathogenicity on rough lemon and they did not invade the rough lemon roots. Four pectate lyase genes (Rs-pel-2, Rs-pel-3, Rs-pel-4, and Rs-pel-5) belonging to the Class III family from these populations were amplified and analysed. The gene Rs-pel-3 could be amplified from six citrus pathotype populations and was stably expressed in the four developmental stages of the nematode, whereas it could not be amplified from the four banana pathotypes. Rs-pel-3 expression may be related to the parasitism and pathogenicity of R. similis on rough lemon. Hence, it can be used as a molecular marker to distinguish between banana and citrus pathotypes and as a target gene for the molecular identification of these two pathotypes. KEY POINTS: • Four pectate lyase genes (Rs-pels) from Radopholus similis were cloned and analysed. • The expression of Rs-pels is different in two pathotypes of Radopholus similis. • A molecular identification method for two pathotypes of Radopholus similis using pectate lyase gene Rs-pel-3 as the target gene was established.


Asunto(s)
Tylenchoidea , Animales , Tylenchoidea/genética , Raíces de Plantas , Polisacárido Liasas/genética , Plantones
2.
MedComm (2020) ; 5(4): e518, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38525111

RESUMEN

Perineural invasion (PNI) leads to the poor prognosis of head and neck squamous cancer (HNSCC) patients, but the mechanism of PNI remains unclear. Dickkopf-1 (DKK1), a secretory protein in the Wnt signaling pathway, was found indeed upregulated in HNSCC cells and tissues. Higher expression of DKK1 was statistically relevant to T stage, N stage, PNI, and poor prognosis of HNSCC. DKK1 overexpression enhanced the migration abilities of cancer cells. Moreover, DKK1-overexpressing cancer cells promoted cancer cells invasion of peripheral nerves in vitro and in vivo. Mechanistically, DKK1 could promote the PI3K-AKT signaling pathway. The migration abilities of neuroblastoma cells, which were enhanced by DKK1-overexpressing HNSCC cell lines, could be reversed by an inhibitor of Akt (MK2206). The association of DKK1 with PNI was also confirmed in HNSCC samples. Variables, including T stage, N stage, DKK1 expression, and PNI, were used to establish a nomogram to predict the survival probability and disease-free probability at 3 and 5 years. In summary, DKK1 can promote the PI3K-AKT signaling pathway in tumor cells and then could induce neuritogenesis and facilitate PNI. MK2206 may be a potential therapeutic target drug for HNSCC patients with PNI.

3.
Adv Mater ; : e2313953, 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38400833

RESUMEN

Engineered bacteria are widely used in cancer treatment because live facultative/obligate anaerobes can selectively proliferate at tumor sites and reach hypoxic regions, thereby causing nutritional competition, enhancing immune responses, and producing anticancer microbial agents in situ to suppress tumor growth. Despite the unique advantages of bacteria-based cancer biotherapy, the insufficient treatment efficiency limits its application in the complete ablation of malignant tumors. The combination of nanomedicine and engineered bacteria has attracted increasing attention owing to their striking synergistic effects in cancer treatment. Engineered bacteria that function as natural vehicles can effectively deliver nanomedicines to tumor sites. Moreover, bacteria provide an opportunity to enhance nanomedicines by modulating the TME and producing substrates to support nanomedicine-mediated anticancer reactions. Nanomedicine exhibits excellent optical, magnetic, acoustic, and catalytic properties, and plays an important role in promoting bacteria-mediated biotherapies. The synergistic anticancer effects of engineered bacteria and nanomedicines in cancer therapy are comprehensively summarized in this review. Attention is paid not only to the fabrication of nanobiohybrid composites, but also to the interpromotion mechanism between engineered bacteria and nanomedicine in cancer therapy. Additionally, recent advances in engineered bacteria-synergized multimodal cancer therapies are highlighted.

4.
BMC Bioinformatics ; 25(1): 29, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233783

RESUMEN

The impairment of sperm maturation is one of the major pathogenic factors in male subfertility, a serious medical and social problem affecting millions of global couples. Regrettably, the existing research on sperm maturation is slow, limited, and fragmented, largely attributable to the lack of a global molecular view. To fill the data gap, we newly established a database, namely the Sperm Maturation Database (SperMD, http://bio-add.org/SperMD ). SperMD integrates heterogeneous multi-omics data (170 transcriptomes, 91 proteomes, and five human metabolomes) to illustrate the transcriptional, translational, and metabolic manifestations during the entire lifespan of sperm maturation. These data involve almost all crucial scenarios related to sperm maturation, including the tissue components of the epididymal microenvironment, cell constituents of tissues, different pathological states, and so on. To the best of our knowledge, SperMD could be one of the limited repositories that provide focused and comprehensive information on sperm maturation. Easy-to-use web services are also implemented to enhance the experience of data retrieval and molecular comparison between humans and mice. Furthermore, the manuscript illustrates an example application demonstrated to systematically characterize novel gene functions in sperm maturation. Nevertheless, SperMD undertakes the endeavor to integrate the islanding omics data, offering a panoramic molecular view of how the spermatozoa gain full reproductive abilities. It will serve as a valuable resource for the systematic exploration of sperm maturation and for prioritizing the biomarkers and targets for precise diagnosis and therapy of male subfertility.


Asunto(s)
Infertilidad Masculina , Maduración del Esperma , Masculino , Humanos , Animales , Ratones , Maduración del Esperma/genética , Semen , Espermatozoides/metabolismo , Epidídimo/metabolismo , Infertilidad Masculina/metabolismo
5.
Protein Expr Purif ; 216: 106431, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38184161

RESUMEN

Human pepsinogens (mainly pepsinogen I and pepsinogen II) are the major inactive precursor forms of the digestive enzyme pepsin which play a crucial role in protein digestion. The levels and ratios of human pepsinogens have demonstrated potential as diagnostic biomarkers for gastrointestinal diseases, particularly gastric cancer. Nanobodies are promising tools for the treatment and diagnosis of diseases, owing to their unique recognition properties. In this study, recombinant human pepsinogens proteins were expressed and purified as immunized antigens. We constructed a VHH phage library and identified several nanobodies via phage display bio-panning. We determined the binding potency and cross-reactivity of these nanobodies. Our study provides technical support for developing immunodiagnostic reagents targeting human pepsinogens.


Asunto(s)
Pepsinógenos , Anticuerpos de Dominio Único , Humanos , Pepsinógenos/metabolismo , Anticuerpos de Dominio Único/genética , Mucosa Gástrica/metabolismo , Pepsina A
6.
Hum Reprod ; 39(2): 310-325, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38011909

RESUMEN

STUDY QUESTION: What is the mechanism behind cryoinjury in human sperm, particularly concerning the interplay between reactive oxygen species (ROS) and autophagy, and how does it subsequently affect sperm fate? SUMMARY ANSWER: The freeze-thaw operation induces oxidative stress by generating abundant ROS, which impairs sperm motility and activates autophagy, ultimately guiding the sperm toward programmed cell death such as apoptosis and necrosis, as well as triggering premature capacitation. WHAT IS KNOWN ALREADY: Both ROS-induced oxidative stress and autophagy are thought to exert an influence on the quality of frozen-thawed sperm. STUDY DESIGN, SIZE, DURATION: Overall, 84 semen specimens were collected from young healthy fertile males, with careful quality evaluation. The specimens were split into three groups to investigate the ROS-induced cryoinjury: normal control without any treatment, sperm treated with 0.5 mM hydrogen peroxide (H2O2) for 1 h, and sperm thawed following cryopreservation. Samples from 48 individuals underwent computer-assisted human sperm analysis (CASA) to evaluate sperm quality in response to the treatments. Semen samples from three donors were analyzed for changes in the sperm proteome after H2O2 treatment, and another set of samples from three donors were analyzed for changes following the freeze-thaw process. The other 30 samples were used for fluorescence-staining and western blotting. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sperm motility parameters, including progressive motility (PR %) and total motility (PR + NP %), were evaluated using the CASA system on a minimum of 200 spermatozoa. The proteomic profiles were determined with label-free mass spectrometry (MS/MS) and protein identification was performed via ion search against the NCBI human database. Subsequently, comprehensive bioinformatics was applied to detect significant proteomic changes and functional enrichment. Fluorescence-staining and western blot analyses were also conducted to confirm the proteomic changes on selected key proteins. The ROS level was measured using 2',7'-dichlorodihydrofluorescein diacetate labeling and the abundance of bioactive mitochondria was determined by evaluating the inner mitochondrial membrane potential (MMP) level. Molecular behaviors of sequestosome-1 (p62 or SQSTM1) and microtubule-associated proteins 1A/1B light chain 3 (LC3) were monitored to evaluate the state of apoptosis in human sperm. Fluorescent probes oxazole yellow (YO-PRO-1) and propidium iodide (PI) were utilized to monitor programmed cell death, namely apoptosis and necrosis. Additionally, gradient concentrations of antioxidant coenzyme Q10 (CoQ10) were introduced to suppress ROS impacts on sperm. MAIN RESULTS AND THE ROLE OF CHANCE: The CASA analysis revealed a significant decrease in sperm motility for both the H2O2-treatment and freeze-thaw groups. Fluorescence staining showed that high ROS levels were produced in the treated sperm and the MMPs were largely reduced. The introduction of CoQ10 at concentrations of 20 and 30 µM resulted in a significant rescue of progressive motility (P < 0.05). The result suggested that excessive ROS could be the major cause of sperm motility impairment, likely by damaging mitochondrial energy generation. Autophagy was significantly activated in sperm when they were under oxidative stress, as evidenced by the upregulation of p62 and the increased conversion of LC3 as well as the upregulation of several autophagy-related proteins, such as charged multivesicular body protein 2a, mitochondrial import receptor subunit TOM22 homolog, and WD repeat domain phosphoinositide-interacting protein 2. Additionally, fluorescent staining indicated the occurrence of apoptosis and necrosis in both H2O2-treated sperm and post-thaw sperm. The cell death process can be suppressed when CoQ10 is introduced, which consolidates the view that ROS could be the major contributor to sperm cryoinjury. The freeze-thaw process could also initiate sperm premature capacitation, demonstrated by the prominent increase in tyrosine phosphorylated proteins, verified with anti-phosphotyrosine antibody and immunofluorescence assays. The upregulation of capacitation-related proteins, such as hyaluronidase 3 and Folate receptor alpha, supported this finding. LARGE SCALE DATA: The data underlying this article are available in the article and its online supplementary material. LIMITATIONS, REASONS FOR CAUTION: The semen samples were obtained exclusively from young, healthy, and fertile males with progressive motility exceeding 60%, which might overemphasize the positive effects while possibly neglecting the negative impacts of cryoinjury. Additionally, the H2O2 treatment conditions in this study may not precisely mimic the oxidative stress experienced by sperm after thawing from cryopreservation, potentially resulting in the omission of certain molecular alterations. WIDER IMPLICATIONS OF THE FINDINGS: This study provides substantial proteomic data for a comprehensive and deeper understanding of the impact of cryopreservation on sperm quality. It will facilitate the design of optimal protocols for utilizing cryopreserved sperm to improve applications, such as ART, and help resolve various adverse situations caused by chemotherapy, radiotherapy, and surgery. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from the Major Innovation Project of Research Institute of National Health Commission (#2022GJZD01-3) and the National Key R&D Program of China (#2018YFC1003600). All authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Preservación de Semen , Semen , Masculino , Humanos , Especies Reactivas de Oxígeno/metabolismo , Semen/metabolismo , Motilidad Espermática , Peróxido de Hidrógeno , Proteómica , Espectrometría de Masas en Tándem , Espermatozoides/metabolismo , Estrés Oxidativo , Criopreservación/métodos , Preservación de Semen/efectos adversos , Preservación de Semen/métodos , Necrosis/metabolismo
7.
Adv Healthc Mater ; 13(11): e2303643, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38115727

RESUMEN

Photodynamic therapy (PDT) with aggregation-induced emission (AIE) photosensitizers (PSs) is a promising therapeutic strategy to achieve better anticancer results. However, eradicating solid tumors completely by PDT alone can be difficult owing to the inherent drawbacks of this treatment, and the combination of PDT with other therapeutic modalities provides opportunities to achieve cooperative enhancement interactions among various treatments. Herein, this work presents the construction of a biocompatible nanocomposite, namely CaO2@DOX@ZIF@ASQ, featuring light-responsive reactive oxygen species (ROS) generation and tumor-targeting oxygen and hydrogen peroxide discharge, as well as controlled doxorubicin (DOX) and copper ion release, thus allowing the combined PDT/CT/CDT effect by AIE PS-enhanced PDT, DOX-based chemotherapy (CT), and copper-involved Fenton-like reaction-driven chemodynamic therapy (CDT). In vitro and in vivo studies verify that the generation of both ROS and O2 by this nanomedicine, stimulated by light, exhibits superior anticancer efficacy, alleviating tumor hypoxia and achieving synergistic PDT/CT/CDT therapeutic effect. This multifunctional nanomedicine remarkably suppresses the tumor growth with minimized systemic toxicity, providing a new strategy for constructing multimodal PDT/CT/CDT therapeutic systems to overcome hypoxia limitations, and potentially increase the antitumor efficacy at lower doses of PSs and chemotherapeutic drugs, thus minimizing potential toxicity to non-malignant tissues.


Asunto(s)
Doxorrubicina , Nanomedicina , Fotoquimioterapia , Fármacos Fotosensibilizantes , Especies Reactivas de Oxígeno , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Animales , Doxorrubicina/farmacología , Doxorrubicina/química , Humanos , Especies Reactivas de Oxígeno/metabolismo , Nanomedicina/métodos , Ratones , Línea Celular Tumoral , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neoplasias/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacología , Ratones Endogámicos BALB C , Femenino , Cobre/química , Cobre/farmacología , Ratones Desnudos
8.
BMC Med Educ ; 23(1): 852, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37946176

RESUMEN

Medical AI has transformed modern medicine and created a new environment for future doctors. However, medical education has failed to keep pace with these advances, and it is essential to provide systematic education on medical AI to current medical undergraduate and postgraduate students. To address this issue, our study utilized the Unified Theory of Acceptance and Use of Technology model to identify key factors that influence the acceptance and intention to use medical AI. We collected data from 1,243 undergraduate and postgraduate students from 13 universities and 33 hospitals, and 54.3% reported prior experience using medical AI. Our findings indicated that medical postgraduate students have a higher level of awareness in using medical AI than undergraduate students. The intention to use medical AI is positively associated with factors such as performance expectancy, habit, hedonic motivation, and trust. Therefore, future medical education should prioritize promoting students' performance in training, and courses should be designed to be both easy to learn and engaging, ensuring that students are equipped with the necessary skills to succeed in their future medical careers.


Asunto(s)
Educación de Pregrado en Medicina , Educación Médica , Estudiantes de Medicina , Humanos , Curriculum , Percepción
9.
Pak J Med Sci ; 39(4): 1003-1007, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37492300

RESUMEN

Objective: To analyze the value of combined detection of tumor markers, neutrophil to lymphocyte ratio (NLR), D-dimer and T lymphocyte in the diagnosis of colon cancer. Methods: This is a retrospective study. A total of 80 patients with colon cancer and 80 patients with benign colon mass admitted to Baoding NO.1 Central Hospital from June 10, 2021 to December 10, 2022 were divided into the study group and the control group. Further comparison was performed on the tumor markers, NLR, D-dimer and T-lymphocyte levels between the two groups, associated with the comparison of corresponding levels of colon cancer at different stages. In addition, correlation analysis was carried out focusing on the above indicators with colon cancer. Results: Carcinoembryonic antigen (CEA), CA199, NLR, D-dimer and CD8+ cell count levels in the study group were significantly higher than those in the control group, while CD4+ cell count and CD4+/CD8+ ratio were obviously lower (P<0.05). Among I-IV colon cancer, the highest levels of CEA, CA199, NLR, D-dimer, CD4+ and CD4+/CD8+ ratio were found in patients with Stage-IV colon cancer, while the level of CD8+ was the lowest (P<0.05). Correlation analysis indicated that CEA, CA199, NLR, D-dimer and CD8+ were positively correlated with whether the patient had colon cancer (r=0.841, 747,991,889,565, all P<0.05), but negative correlations with CD4+ and CD4+/CD8+ ratio (r=-0.999, -0.994, all P<0.05). Conclusion: The detection of tumor markers combined with NLR, D-dimer and T-lymphocytes has reference value in the diagnosis of colon cancer.

10.
Adv Mater ; 35(40): e2302954, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37354126

RESUMEN

Improving the output energy and durability of triboelectric nanogenerators (TENGs) remains a considerable challenge for their practical applications. Owing to the interface effect of triboelectrification and electrostatic induction, thinner films with higher dielectric constants yield a higher output; however, they are not durable for practical applications. Herein, the dielectric surface effect is changed into a volume effect by adopting a millimeter-thick dielectric film with an inner porous network structure so that charges can hop in the surface state of the network. Charge migration inside the dielectric film is the key factor affecting the output of the triboelectric nanogenerator (TENG) with a thick film, based on which each working stage follows the energy-maximization principle in the voltage-charge plot. The maximum peak and average power densities of the TENG with polyurethane foam film in 1 mm thickness reach 40.9 and 20.7 W m-2  Hz-1 , respectively, under environmental conditions, and the output charge density is 5.14 times that of TENGs with a poly(tetrafluoroethylene) film of the same thickness. Superdurability is achieved in the rotary-mode TENG after 200 000 operation cycles. This study identifies the physical mechanism of the thick dielectric film used in TENGs and provides a new approach to promote the output and durability of TENGs.

11.
Opt Lett ; 48(9): 2241-2244, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37126244

RESUMEN

We demonstrate stable mode-locked pulses in an erbium-doped fiber laser (EDFL) using a femtosecond laser-inscribed small-period long-period grating (SP-LPG). The SP-LPG has a period of 25 µm and a length of 2.5 mm. The polarization dependent loss (PDL) of the SP-LPG reaches 20 dB at the wavelength of 1556 nm and 25 dB at the wavelength of 1607 nm, which is sufficient to trigger the mode-locking mechanism. In addition, a mode-locked fiber laser (MLFL) based on the SP-LPG has been demonstrated to generate 1.58-ps pulses at 1577 nm with a bandwidth of 4 nm and a repetition rate of 1.54 MHz. The signal-to-noise ratio (SNR) of 50 dB shows the high stability of this system. This work indicates various potential applications of the SP-LPG in ultra-fast laser technologies due to its simple fabrication, compact structure, and high damage threshold.

12.
Foods ; 12(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36673453

RESUMEN

The processing quality of wheat is affected by seed storage substances, such as protein and starch. High-molecular-weight glutenin subunits (HMW-GSs) are the major components of wheat seed storage proteins (SSPs); they are also key determinators of wheat end-use quality. However, the effects of HMW-GSs absence on the expression of other storage substances and the regulation mechanism of HMW-GSs are still limited. Previously, a wheat transgenic line LH-11 with complete deletions of HMW-GSs was obtained through introducing an exogenous gene Glu-1Ebx to the wild-type cultivar Bobwhite by transgenic approach. In this study, comparative seed transcriptomics and proteomics of transgenic and non-transgenic lines at different seed developmental stages were carried out to explore the changes in genes and proteins and the underlying regulatory mechanism. Results revealed that a number of genes, including genes related to SSPs, carbohydrates metabolism, amino acids metabolism, transcription, translation, and protein process were differentially enriched. Seed storage proteins displayed differential expression patterns between the transgenic and non-transgenic line, a major rise in the expression levels of gliadins were observed at 21 and 28 days post anthesis (DPA) in the transgenic line. Changes in expressions of low-molecular-weight glutenins (LMW-GSs), avenin-like proteins (ALPs), lipid transfer proteins (LTPs), and protease inhibitors (PIs) were also observed. In addition, genes related to carbohydrate metabolism were differentially expressed, which probably leads to a difference in starch component and deposition. A list of gene categories participating in the accumulation of SSPs was proposed according to the transcriptome and proteome data. Six genes from the MYB and eight genes from the NAC transcription families are likely important regulators of HMW-GSs accumulation. This study will provide data support for understanding the regulatory network of wheat storage substances. The screened candidate genes can lay a foundation for further research on the regulation mechanism of HMW-GSs.

13.
Int Dent J ; 73(4): 550-557, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36481093

RESUMEN

OBJECTIVE: This study aimed to reveal the geographic accessibility of dental clinics for most municipalities in Japan in 2015 and to explore the association between dental accessibility and dental caries status in 3-year-old children. METHODS: We computed the accessibility index and accessibility index rate for the population outside a 1-km radius of dental clinics using a geographic information system. We also used spatial autocorrelation analysis (Moran's I statistic) to examine the spatial clustering patterns of dental accessibility in Japanese municipalities. In addition, we adjusted the prevalence of dental caries for most municipalities using empirical Bayesian estimation. Finally, we applied multiple linear regression to scrutinise the associations between dental caries status, including the prevalence of dental caries and decayed and filled teeth (dft), and dental accessibility, with adjustments made for other sociodemographic variables. RESULTS: The distribution of dental accessibility in Japanese municipalities is relatively unequal. Dental accessibility is decent in the 3 metropolitan areas around Tokyo, Osaka, and Nagoya but poor in the Tohoku and Kyushu regions. In addition, dental accessibility is significantly related to the prevalence of dental caries and dft after adjusting for other sociodemographic variables (P < .005). CONCLUSIONS: This study suggests that dental accessibility is considerably connected to the dental caries status of 3-year-old children after excluding financial burden. Preschool children in areas with poor dental accessibility are likely to have poor dental caries status. We also verified the inequality of dental accessibility amongst Japanese municipalities. For the future development of primary oral health care, more attention should be paid to people with a disadvantage in terms of dental accessibility.


Asunto(s)
Caries Dental , Preescolar , Humanos , Caries Dental/epidemiología , Sistemas de Información Geográfica , Teorema de Bayes , Susceptibilidad a Caries Dentarias , Pueblos del Este de Asia , Prevalencia , Índice CPO
16.
Opt Express ; 30(20): 35911-35922, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36258531

RESUMEN

We demonstrated an ultrafast Yb-doped fiber laser with a single mode fiber-graded index multimode fiber-single mode fiber (SMF-GIMF-SMF) structure based saturable absorber. The GIMF was placed in the groove of an in-line fiber polarization controller to adjust its birefringence, enabling the SMF-GIMF-SMF structure to realize efficient saturable absorption based on nonlinear multimode interference without strict length restriction. By adjusting two intra-cavity polarization controllers, stable dissipation solitons and noise-like pulses were achieved in the 1030 nm waveband with pulse durations of 10.67 ps and 276 fs, respectively. We also realized Q-switched mode-locked pulses in the same fiber laser cavity. By the dispersive Fourier transform method, the real-time spectral evolution in the buildup process of the Q-switched mode-locked state was captured, which showed that the continuous-wave in this laser could gradually evolved into the stable Q-switched mode-locked pulses through unstable self-pulsation, relaxation oscillation and rogue Q-switching stage. To the best of our knowledge, our work reveals the buildup dynamics of the Q-switched mode-locked operation in a fiber laser for the first time. And we also studied the real-time spectral evolution of the stable Q-switched mode-locked pulses, which exhibited periodic breathing property.

17.
ACS Appl Mater Interfaces ; 14(43): 48636-48646, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36273325

RESUMEN

The triboelectric nanogenerator (TENG) as an ideal low-frequency mechanical energy harvester has received extensive attention, while low output charge density limits its application. A charge excitation strategy is one of the techniques to effectively improve the surface charge density of the TENG. However, there is little in-depth research on the matching factors between the TENG and excitation circuit. Herein, a soft-contact charge excitation rotary TENG (SCER-TENG) is developed to explore the matching mechanism of different charge excitation strategies. The total output power transferred by the voltage-multiplying circuit (VMC) is 2.13 times that of the full-wave bridge rectifier, which effectively improves the output performance of the SCER-TENG. Moreover, through the established capacitor model and the theoretically calculated maximum output charge of the SCER-TENG with VMC and Zener diodes (VMC-Z), it is found that the output of the Main TENG is mainly affected by capacitors and Zener diodes. The theories have been verified by experiments. After optimization, the output charge of the Main TENG with VMC-Z (1.54 µC) is 3850% higher than that without excitation (0.04 µC). The SCER-TENG successfully harvests low-speed (2.5 m s-1) wind energy to form a self-powered system. This work has crucial instructive implications for using charge excitation strategies to improve the performance of the rotary TENG.

18.
Front Plant Sci ; 13: 1006409, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36110359

RESUMEN

Cytokinin is an important endogenous hormone in plants performing a wide spectrum of biological roles. The type-A response regulators (RRAs) are primary cytokinin response genes, which are important components of the cytokinin signaling pathway and are involved in the regulation of plant growth and development. By analysis of the whole genome sequence of wheat, we identified 20 genes encoding RRAs which were clustered into eight homologous groups. The gene structure, conserved motifs, chromosomal location, and cis-acting regulatory elements of the TaRRAs were analyzed. Quantitative real-time polymerase chain reaction (qRT-PCR) results showed that the expression levels of most of the TaRRAs increased rapidly on exogenous cytokinin application. Moreover, the TaRRA family members displayed different expression profiles under the stress treatments of drought, salt, cold, and heat. This study provides valuable insights into the RRA gene family in wheat and promotes the potential application of these genes in wheat genetic improvement.

19.
Front Microbiol ; 13: 908329, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35935228

RESUMEN

Aim: The aroma-producing strain of Geotrichum candidum GDMCC60675 was taken as the research object, the composition of aroma-producing substances of G. candidum was studied, and the target strains of G. candidum suitable for food additives were screened out by mutagenesis. Methods: Mutants were obtained by space breeding. The colony morphology and cell morphology of the mutant strain were identified, the phylogenetic tree of the two strains was constructed, and the whole-genome sequences of the wild strain and the mutant strain were compared. The aroma components and key odor compounds of the two strains were analyzed and compared by HS-SPME-GC-MS and E-nose detection, and the data were processed by using the relative odor activity value (ROAV) analysis method. Results: A mutant strain of G. candidum was found with different characteristics of aroma production compared with wild-type G. candidum. It was found that its colony morphology and cell morphology were similar. However, it was found that the aroma-producing substances produced by the two strains were different, and the key difference compound was phenyl ethyl alcohol, which also proved that the two strains were different, and the main aroma note was different.

20.
Front Immunol ; 13: 803097, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35720287

RESUMEN

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by heterogeneous inflammatory endotypes of unknown etiology. Invariant natural killer T (iNKT) cells are multifunctional innate T cells that exhibit Th1-, Th2-, and Th17-like characteristics. We investigated functional relationships between iNKT cells and inflammatory subtypes of CRSwNP. Eighty patients with CRSwNP and thirty-two control subjects were recruited in this study. Flow cytometry was used to analyze the frequencies and functions of iNKT cells and their subsets in peripheral blood mononuclear cells (PBMCs) and tissues. Polyp tissue homogenates were used to study the multifunctionality of iNKT cells. iNKT cells were significantly increased in polyps (0.41%) than in control mucosa (0.12%). iNKT cells were determined in the paucigranunlocytic (n=20), eosinophilic (n=22), neutrophilic (n=23), and mixed granulocytic (n=13) phenotypes of CRSwNP. The percentages of iNKT cells and HLA-DR+PD-1+ subsets were lower in eosinophilic or mixed granulocytic polyps than those of other phenotypes. iNKT cells and subsets were enriched in polyp tissues than in matched PBMCs. The evaluation of surface markers, transcription factors, and signature cytokines indicated that the frequencies of iNKT2 and iNKT17 subsets were significantly increased in eosinophilic and neutrophilic polyps, respectively, than in the paucigranulocytic group. Moreover, the production of type 2 (partially dependent on IL-7) and type 17 (partially dependent on IL-23) iNKT cells could be stimulated by eosinophilic and neutrophilic homogenates, respectively. Our study revealed that type 2 and type 17 iNKT cells were involved in eosinophilic and neutrophilic inflammation, respectively, in CRSwNP, while different inflammatory microenvironments could modulate the functions of iNKT cells, suggesting a role of iNKT cells in feedback mechanisms and local inflammation.


Asunto(s)
Pólipos Nasales , Células T Asesinas Naturales , Rinitis , Sinusitis , Enfermedad Crónica , Humanos , Inflamación , Membrana Mucosa , Pólipos Nasales/genética , Rinitis/genética , Sinusitis/genética
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