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1.
Environ Sci Technol ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38857061

RESUMEN

Conversion from natural lands to cropland, primarily driven by agricultural expansion, could significantly alter soil microbiome worldwide; however, influences of forest-to-cropland conversion on microbial hierarchical interactions and ecosystem multifunctionality have not been fully understood. Here, we examined the effects of forest-to-cropland conversion on intratrophic and cross-trophic microbial interactions and soil ecosystem multifunctionality and further disclosed their underlying drivers at a national scale, using Illumina sequencing combined with high-throughput quantitative PCR techniques. The forest-to-cropland conversion significantly changed the structure of soil microbiome (including prokaryotic, fungal, and protistan communities) while it did not affect its alpha diversity. Both intrakingdom and interkingdom microbial networks revealed that the intratrophic and cross-trophic microbial interaction patterns generally tended to be more modular to resist environmental disturbance introduced from forest-to-cropland conversion, but this was insufficient for the cross-trophic interactions to maintain stability; hence, the protistan predation behaviors were still disturbed under such conversion. Moreover, key soil microbial clusters were declined during the forest-to-cropland conversion mainly because of the increased soil total phosphorus level, and this drove a great degradation of the ecosystem multifunctionality (by 207%) in cropland soils. Overall, these findings comprehensively implied the negative effects of forest-to-cropland conversion on the agroecosystem, from microbial hierarchical interactions to ecosystem multifunctionality.

2.
J Hazard Mater ; 466: 133567, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38271874

RESUMEN

Arsenic (As) and cadmium (Cd) pose potential ecological threats to cropland soils; however, few studies have investigated their combined effects on multilevel organisms and soil functioning. Here, we used collembolans and soil microbiota as test organisms to examine their responses to soil As and Cd co-contamination at the gene, individual, and community levels, respectively, and further uncovered ecological relationships between pollutants, multilevel organisms, and soil functioning. At the gene level, collembolan transcriptome revealed that elevated As concentrations stimulated As-detoxifying genes AS3MT and GST, whereas the concurrent Cd restrained GST gene expression. At the individual level, collembolan reproduction was sensitive to pollutants while collembolan survival wasn't. At the community level, significant but inconsistent correlations were observed between the biodiversity of different soil keystone microbial clusters and soil As levels. Moreover, soil functioning related to nutrient (e.g., carbon, nitrogen, phosphorus, and sulfur) cycles was inhibited under As and Cd co-exposure only through the mediation of plant pathogens. Overall, these findings suggested multilevel bioindicators (i.e., AS3MT gene expression in collembolans, collembolan reproduction, and biodiversity of soil keystone microbial clusters) in cropland soils co-contaminated with As and Cd, thus improving the understanding of the ecotoxicological impact of heavy metal co-contamination on soil ecosystems.


Asunto(s)
Arsénico , Contaminantes Ambientales , Microbiota , Contaminantes del Suelo , Cadmio/metabolismo , Arsénico/toxicidad , Arsénico/análisis , Suelo , Multiómica , Microbiota/genética , Contaminantes Ambientales/análisis , Productos Agrícolas/metabolismo , Reacción en Cadena de la Polimerasa , Contaminantes del Suelo/metabolismo
3.
BMC Genomics ; 24(1): 766, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38087211

RESUMEN

BACKGROUND: Sea cucumbers exhibit a remarkable ability to regenerate damaged or lost tissues and organs, making them an outstanding model system for investigating processes and mechanisms of regeneration. They can also reproduce asexually by transverse fission, whereby the anterior and posterior bodies can regenerate independently. Despite the recent focus on intestinal regeneration, the molecular mechanisms underlying body wall regeneration in sea cucumbers still remain unclear. RESULTS: In this study, transverse fission was induced in the tropical sea cucumber, Holothuria leucospilota, through constrainment using rubber bands. Histological examination revealed the degradation and loosening of collagen fibers on day-3, followed by increased density but disorganization of the connective tissue on day-7 of regeneration. An Illumina transcriptome analysis was performed on the H. leucospilota at 0-, 3- and 7-days after artificially induced fission. The differential expression genes were classified and enriched by GO terms and KEGG database, respectively. An upregulation of genes associated with extracellular matrix remodeling was observed, while a downregulation of pluripotency factors Myc, Klf2 and Oct1 was detected, although Sox2 showed an upregulation in expression. In addition, this study also identified progressively declining expression of transcription factors in the Wnt, Hippo, TGF-ß, and MAPK signaling pathways. Moreover, changes in genes related to development, stress response, apoptosis, and cytoskeleton formation were observed. The localization of the related genes was further confirmed through in situ hybridization. CONCLUSION: The early regeneration of H. leucospilota body wall is associated with the degradation and subsequent reconstruction of the extracellular matrix. Pluripotency factors participate in the regenerative process. Multiple transcription factors involved in regulating cell proliferation were found to be gradually downregulated, indicating reduced cell proliferation. Moreover, genes related to development, stress response, apoptosis, and cell cytoskeleton formation were also involved in this process. Overall, this study provides new insights into the mechanisms of whole-body regeneration and uncover potential cross-species regenerative-related genes.


Asunto(s)
Holothuria , Pepinos de Mar , Animales , Pepinos de Mar/genética , Holothuria/genética , Regeneración/genética , Perfilación de la Expresión Génica , Factores de Transcripción/genética
4.
J Vis Exp ; (200)2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37870359

RESUMEN

Parasitoid wasps are a diverse group of hymenopteran insects that serve as invaluable resources for pest biocontrol. To ensure successful parasitism, parasitoid wasps inject venom into their hosts to suppress their hosts' immunity, modulate hosts' development, metabolism, and even behavior. With over 600,000 estimated species, the diversity of parasitoid wasps surpasses that of other venomous animals, such as snakes, cone snails, and spiders. Parasitoid wasp venom is an underexplored source of bioactive molecules with potential applications in pest control and medicine. However, collecting parasitoid venom is challenging due to the inability to use direct or electrical stimulation and the difficulty in dissection because of their small size. Trichogramma is a genus of tiny (~0.5 mm) egg parasitoid wasps that are widely used for the biological control of lepidopteran pests in both agriculture and forests. Here, we report a method for extracting venom from T. dendrolimi using artificial hosts. These artificial hosts are created with polyethylene film and amino acid solutions and then inoculated with Trichogramma wasps for parasitism. The venom was subsequently collected and concentrated. This method enables the extraction of large amounts of Trichogramma venom while avoiding contamination from other tissues caused by dissection, a common issue in venom reservoir dissection protocols. This innovative approach facilitates the study of Trichogramma venom, paving the way for new research and potential applications.


Asunto(s)
Avispas , Animales , Avispas/fisiología , Ponzoñas
5.
Acta Biochim Biophys Sin (Shanghai) ; 55(10): 1659-1667, 2023 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-37654074

RESUMEN

Aging is a pressing global health issue that is linked to various diseases, such as diabetes and Alzheimer's disease. It is well known that glycation plays a pathological role in the aging process and age-related diseases. Thus, it is of great significance to discover protein glycation at an early stage for monitoring and intervention in the aging process. However, the endogenous age-related early-stage glycated proteome remains insufficiently profiled. To address this research gap, our study focuses on assessing glycated proteomics profiles in the serum of mice. We employ a robust and quantitative strategy previously developed by our team, to analyze endogenous glycated proteome in serum samples of 4 age groups of mice (10 weeks, 16 weeks, 48 weeks and 80 weeks). In total, 2959 endogenous glycated peptides corresponding to 296 serum proteins are identified from 48 runs of serum samples from 16 mice across the four age groups. By comparing these glycated peptides between adjacent age groups, we discover 49 glycated peptides from 35 proteins that show significant upregulation between the 48-week and 80-week age groups. Furthermore, we identify 10 glycated proteins (or protein groups) that are significantly upregulated only between the 48-week and 80-week age groups, including lecithin-cholesterol acyltransferase (LCAT) and apolipoprotein A-II (Apo A-II). These novel findings provide unique signatures for understanding the aging process and age-related diseases. By shedding light on the early-stage glycated proteome, our study contributes valuable insights that may have implications for future interventions and therapeutic approaches.


Asunto(s)
Diabetes Mellitus , Proteoma , Animales , Ratones , Proteoma/metabolismo , Glicosilación , Proteinas Glicosiladas , Péptidos/metabolismo
6.
Molecules ; 28(13)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37446798

RESUMEN

In this work, two-dimensional (2D) Zn-HMT (Zn(NO3)2(HMT)2(H2O)2]n) nanosheets were synthesized using a facile one-step chemical precipitation in the presence of Zn(NO3)2, hexamine (HMT), and anhydrous ethanol at room temperature. Subsequently, hexagonal Tx-ZnO (Tx-ZnO refers to the zinc oxide (ZnO) nanoparticles) were synthesized by a high-temperature solid-phase method at different temperatures (x = 500, 550, 600, 650, 700, 750, and 800 °C) nanoparticles with different morphologies were synthesized by a high-temperature calcination approach using 2D Zn-HMT nanosheets as precursor. The crystal structure, morphology, specific surface areas, surface and interface properties, optical properties, and charge migration behaviors of the as-synthesized Tx-ZnO nanoparticles were characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), automatic specific surface and aperture analyzer, X-ray photoelectron spectroscopy (XPS), UV-visible spectrophotometer, photoluminescence (PL) spectra, and electrochemical impedance spectroscopy (EIS). The photocatalytic performances and stabilities of the as-synthesized typical Tx-ZnO nanoparticles with various morphologies were evaluated and compared with the commercial ZnO (CM-ZnO) nanoparticle. The T700-ZnO nanoparticle with spherical and irregular morphology exhibited the highest photocatalytic activity (99.12%) for the degradation of Rhodamine B (RhB), compared to T500-ZnO (92.32%), T600-ZnO (90.65%), T800-ZnO (44.04%), and the CM-ZnO (88.38%) nanoparticle, which can be attributed to the cooperative effects of higher crystallinity, bigger crystal size, the strongest separation efficiency, the lowest recombination rate, the fastest charge carrier transfer path, and the highest charge-transfer efficiency. The superior photocatalytic activity illustrated by the T700-ZnO nanoparticle makes it have potential application prospects for the treatment of organic wastewater.


Asunto(s)
Nanopartículas , Óxido de Zinc , Óxido de Zinc/química , Rayos Ultravioleta , Rodaminas/química
7.
Educ Inf Technol (Dordr) ; 28(1): 237-253, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35789765

RESUMEN

The purpose of the qualitative study was to investigate instructors' experiences of engaging non-traditional learners in eCampus. Online education was rapidly growing in many higher education institutions, especially during the pandemic. However, a high attrition rate could negatively impact student success. Research findings showed that engagement was a significant factor to increase students' online retention. Due to the flexibility and accessibility of online education, there was a high demand among non-traditional learners. However, limited research has been conducted to explore instructors' experiences while engaging non-traditional learners in eCampus. In the general qualitative study, twelve online instructors were recruited, and interviews and document analysis were used to collect data. The findings showed that instructors faced both challenges and opportunities while increasing engagement among non-traditional learners in online programs. These indicated the need for the diversity of course design, relationship and community building, the flexibility of engagement criteria, and the unpredictability of emotional engagement. Institutional support and resources were recommended to improve the future teaching practices and the success of online learners with underrepresented backgrounds.

8.
Curr Med Chem ; 30(20): 2247-2266, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36043743

RESUMEN

The sartans are a new class of antihypertensive drugs as angiotensin II receptor blockers which possess plenty of advantages in treating hypertension and related pathologies. This review describes the clinical treatment, side effects, and potential therapeutic effects of sartans from 1995 to date. The synthesis, structural-activity and molecular docking with Angiotensin Type 1 receptor of imidazole derivatives, benzimidazole derivatives and other compounds are also described. With a clear Structure-Activity Relationship and abundant pharmacological effects, some types of novel Angiotensin Type 1 receptor antagonists are emerging gradually for further research in the meantime.


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II , Hipertensión , Humanos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/efectos adversos , Receptor de Angiotensina Tipo 1 , Simulación del Acoplamiento Molecular , Antihipertensivos/farmacología , Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Antagonistas de Receptores de Angiotensina/uso terapéutico , Relación Estructura-Actividad
9.
Front Plant Sci ; 14: 1342219, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38328618

RESUMEN

Legumes play a crucial role in the restoration and utilization of salinized grassland. To explore the physiological response mechanism of Astragalus membranaceus and Medicago sativa seedlings to salt stress, salt stress culture experiments with five NaCl concentration treatments (0 mmol/L, 50 mmol/L, 100 mmol/L, 200 mmol/L, and 300 mmol/L) were conducted on these two legume seedlings. Morphological characteristics, physiological features, biomass, and the protective enzyme system were measured for both seedlings. Correlation analysis, principal component analysis (PCA), and membership function analysis (MFA) were conducted for each index. Structural equation modeling (SEM) was employed to analyze the salt stress pathways of plants. The results indicated that number of primary branches (PBN), ascorbate peroxidase (APX) activity in stems and leaves, catalase (CAT) activity in roots, etc. were identified as the primary indicators for evaluating the salt tolerance of A. membranaceus during its seedling growth period. And CAT and peroxidase (POD) activity in roots, POD and superoxide dismutase (SOD) activity in stems and leaves, etc. were identified as the primary indicators for evaluating the salt tolerance of M. sativa during its growth period. Plant morphological characteristics, physiological indexes, and underground biomass (UGB) were directly affected by salinity, while physiological indexes indirectly affected the degree of leaf succulence (LSD). Regarding the response of the protective enzyme system to salt stress, the activity of POD and APX increased in A. membranaceus, while the activity of CAT increased in M. sativa. Our findings suggest that salt stress directly affects the growth strategies of legumes. Furthermore, the response of the protective enzyme system and potential cell membrane damage to salinity were very different in the two legumes.

10.
Mol Cells ; 45(12): 923-934, 2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36572561

RESUMEN

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have great potential in applications such as regenerative medicine, cardiac disease modeling, and in vitro drug evaluation. However, hPSC-CMs are immature, which limits their applications. During development, the maturation of CMs is accompanied by a decline in their proliferative capacity. This phenomenon suggests that regulating the cell cycle may facilitate the maturation of hPSC-CMs. Aurora kinases are essential kinases that regulate the cell cycle, the role of which is not well studied in hPSC-CM maturation. Here, we demonstrate that CYC116, an inhibitor of Aurora kinases, significantly promotes the maturation of CMs derived from both human embryonic stem cells (H1 and H9) and iPSCs (induced PSCs) (UC013), resulting in increased expression of genes related to cardiomyocyte function, better organization of the sarcomere, increased sarcomere length, increased number of mitochondria, and enhanced physiological function of the cells. In addition, a number of other Aurora kinase inhibitors have also been found to promote the maturation of hPSC-CMs. Our data suggest that blocking aurora kinase activity and regulating cell cycle progression may promote the maturation of hPSC-CMs.


Asunto(s)
Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes , Humanos , Miocitos Cardíacos , Diferenciación Celular
11.
Front Plant Sci ; 13: 852750, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35557713

RESUMEN

Bacterial soft rot is one of the most destructive diseases of taro (Colocasia esculenta) worldwide. In recent years, frequent outbreaks of soft rot disease have seriously affected taro production and became a major constraint to the development of taro planting in China. However, little is known about the causal agents of this disease, and the only reported pathogens are two Dickeya species and P. carotovorum. In this study, we report taro soft rot caused by two novel Pectobacterium strains, LJ1 and LJ2, isolated from taro corms in Ruyuan County, Shaoguan City, Guangdong Province, China. We showed that LJ1 and LJ2 fulfill Koch's postulates for taro soft rot. The two pathogens can infect taro both individually and simultaneously, and neither synergistic nor antagonistic interaction was observed between the two pathogens. Genome sequencing of the two strains indicated that LJ1 represents a novel species of the genus Pectobacterium, for which the name "Pectobacterium colocasium sp. nov." is proposed, while LJ2 belongs to Pectobacterium aroidearum. Pan-genome analysis revealed multiple pathogenicity-related differences between LJ1, LJ2, and other Pectobacterium species, including unique virulence factors, variation in the copy number and organization of Type III, IV, and VI secretion systems, and differential production of plant cell wall degrading enzymes. This study identifies two new soft rot Pectobacteriaceae (SRP) pathogens causing taro soft rot in China, reports a new case of co-infection of plant pathogens, and provides valuable resources for further investigation of the pathogenic mechanisms of SRP.

12.
J Environ Sci (China) ; 120: 53-62, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35623772

RESUMEN

Penicillium oxalicum SL2 (SL2) is a previously screened Pb-tolerant fungus that can promote crops growth. The relationship between SL2 colonization and Pb immobilization was studied to provide a theoretical basis for microbial remediation of Pb-contaminated paddy soil. In this study, green fluorescent protein (GFP) labeled SL2 was inoculated into different Pb-contaminated paddy soils (S1-S6). The Pb extracted from the soil by HNO3, EDTA and CaCl2 were used to characterize the available Pb. The results showed that the colonization of SL2 was divided into lag phase (0-7 days), growth phase (7-30 days), and mortality phase (30-90 days). SL2 colonized well in sandy soils rich in clay and total phosphorus with initial pH of 4.5-7.0. In addition, SL2 increased soil pH and decreased soil Eh, which was beneficial to immobilize Pb. In different soils, the highest percentages of CaCl2-Pb, EDTA-Pb, and HNO3-Pb immobilized by SL2 were 34.34%-40.53%, 17.05%-20.11%, and 7.39%-15.62%, respectively. Pearson correlation analysis showed that the percentages of CaCl2-Pb and EDTA-Pb immobilized by SL2 were significantly positively correlated with the number of SL2 during the growth phase. SL2 mainly immobilized Pb in the growth phase and a higher peak number of SL2 was beneficial to the immobilization of Pb.


Asunto(s)
Contaminantes del Suelo , Suelo , Cloruro de Calcio , Ácido Edético , Plomo/análisis , Penicillium , Suelo/química , Contaminantes del Suelo/análisis
13.
J Oncol ; 2022: 9942918, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35368889

RESUMEN

Objective: To evaluate the efficacy of the PD-1 inhibitor camrelizumab plus chemotherapy in the first-line treatment of advanced non-small-cell lung cancer (NSCLC) and the prognostic differences of patients with different PET/CT features. Methods: Between December 2018 and October 2020, 100 patients with NSCLC assessed for eligibility treated in our institution were recruited and randomly assigned (1 : 1) to receive either the TC regimen chemotherapy (control group) or the TC regimen chemotherapy plus camrelizumab (study group). The primary endpoints were clinical efficacy, progression-free survival (PFS), and overall survival (OS). A decrease of max standard uptake value (SUVmax) of >30% in primary lung cancer was considered as metabolic remission. The prognostic differences of the eligible patients with different PET/CT features were assessed. Survival data were analyzed using the Kaplan-Meier method to obtain the survival rate and calculate the median survival time. Results: The metabolic remission rate and objective remission rate were significantly higher with chemotherapy plus camrelizumab versus chemotherapy alone. The study group had significantly higher CD3+ and CD4+ T-cell ratios and CD4+/CD8+ ratio and significantly lower CD8+ T-cell ratio than the control group after treatment. PFS (10 months versus 4 months) and OS (HR = 37.094, P ≤ 0.001) were better with camrelizumab plus chemotherapy versus stand-alone chemotherapy. The incidence of adverse events (AE) was similar between the two groups. The patients in the study group were stratified into metabolic remission and metabolic nonremission based on PET/CT results. Intersubgroup analysis showed significantly better PFS and OS in the metabolic remission group than in the nonmetabolic remission group. Conclusion: The camrelizumab plus chemotherapy as a first-line treatment option for NSCLC significantly increases the survival benefit. Metabolic status shown by PET/CT correlates with long-term prognosis and demonstrates a great potential for early assessment of efficacy to support the choice of treatment regimens.

14.
TechTrends ; 66(1): 47-55, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34806092

RESUMEN

The purpose of this autoethnography is to share my perspective of course design and delivery considerations based on my professional experience as an instructional designer for a virtual international exchange program during the COVID-19 pandemic. Due to the impact of the global pandemic, the partner institutions decided to take advantage of distance education to continue their exchange program. I was the instructional designer to support faculty's transition to online instruction. Little research has been conducted to explore instructional design practices for distance teaching and learning in an intercultural context. Therefore, I applied an individual autoethnography to collect and analyze data from my narratives and artifacts to understand my perspective of instructional design and delivery practices within a cross-cultural distance learning environment. The findings showed course design in transnational distance contexts was more complicated than in distance education in a single cultural context. My role as an instructional designer was influenced by factors at both micro and macro levels.

15.
Environ Pollut ; 274: 116599, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33540260

RESUMEN

Lead contamination in soil has become a worldwide threat on food security and human health. To assess the Pb bioavailability and evaluate the safe use of low Pb polluted soil for food production, the speciation of Pb in 19 types of paddy soil were investigated by chemical extraction and X-ray absorption near-edge structure (XANES), and the uptake and accumulation characteristics of Pb in different soil-rice systems were investigated. Moreover, an empirical model was established to predict the content of Pb in rice grain, and field validation was conduct to evaluate model performance. Results showed that the proportion of available Pb in different soil satisfied normal distribution N (0.47, 0.23). Pb(CH3COO)2, GSH-Pb, PbO, PbHPO4 and Pb3(PO4)2 performed well in characterizing the speciation of Pb in different rhizosphere soils, and PbHPO4 accounted for more than 70%. The exceedance of Pb in grain in CK, 0.5X and 1X treatment were 10.5%, 36.1% and 42.1%, respectively, and the accumulation of Pb in grain was significantly related with Pb content in root. Carbonate and organic bound Pb in rhizosphere soil were two major Pb species that influenced the accumulation of Pb in rice. Moreover, content of total Pb, clay and SOM performed well in predicting the Pb content in grain, both for pot and field samples. Above all, our predicting model worked well in evaluating Pb accumulation in rice grain among low polluted paddy farmland (Total Pb < 300 mg/kg).


Asunto(s)
Oryza , Contaminantes del Suelo , Grano Comestible/química , Humanos , Plomo , Suelo , Contaminantes del Suelo/análisis
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