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1.
Mol Cell Proteomics ; 23(3): 100729, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309569

RESUMO

Diagnosing, predicting disease outcome, and identifying effective treatment targets for virus-related cancers are lacking. Protein biomarkers have the potential to bridge the gap between prevention and treatment for these types of cancers. While it has been shown that certain antibodies against EBV proteins could be used to detect nasopharyngeal carcinoma (NPC), antibodies targeting are solely a tiny part of the about 80 proteins expressed by the EBV genome. Furthermore, it remains unclear what role other viruses play in NPC since many diseases are the result of multiple viral infections. For the first time, this study measured both IgA and IgG antibody responses against 646 viral proteins from 23 viruses in patients with NPC and control subjects using nucleic acid programmable protein arrays. Candidate seromarkers were then validated by ELISA using 1665 serum samples from three clinical cohorts. We demonstrated that the levels of five candidate seromarkers (EBV-BLLF3-IgA, EBV-BLRF2-IgA, EBV-BLRF2-IgG, EBV-BDLF1-IgA, EBV-BDLF1-IgG) in NPC patients were significantly elevated than controls. Additional examination revealed that NPC could be successfully diagnosed by combining the clinical biomarker EBNA1-IgA with the five anti-EBV antibodies. The sensitivity of the six-antibody signature at 95% specificity to diagnose NPC was comparable to the current clinically-approved biomarker combination, VCA-IgA, and EBNA1-IgA. However, the recombinant antigens of the five antibodies are easier to produce and standardize compared to the native viral VCA proteins. This suggests the potential replacement of the traditional VCA-IgA assay with the 5-antibodies combination to screen and diagnose NPC. Additionally, we investigated the prognostic significance of these seromarkers titers in NPC. We showed that NPC patients with elevated BLLF3-IgA and BDLF1-IgA titers in their serum exhibited significantly poorer disease-free survival, suggesting the potential of these two seromarkers as prognostic indicators of NPC. These findings will help develop serological tests to detect and treat NPC in the future.


Assuntos
Neoplasias Nasofaríngeas , Proteoma , Humanos , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Herpesvirus Humano 4/genética , Proteínas do Capsídeo , Antígenos Virais , Biomarcadores , Imunoglobulina G , Imunoglobulina A
2.
Plant J ; 118(6): 2188-2201, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38581688

RESUMO

Moving from sole cropping to intercropping is a transformative change in agriculture, contributing to yield. Soybeans adapt to light conditions in intercropping by adjusting the onset of reproduction and the inflorescence architecture to optimize reproductive success. Maize-soybean strip intercropping (MS), maize-soybean relay strip intercropping (IS), and sole soybean (SS) systems are typical soybean planting systems with significant differences in light environments during growth periods. To elucidate the effect of changes in the light environment on soybean flowering processes and provide a theoretical basis for selecting suitable varieties in various planting systems to improve yields, field experiments combining planting systems (IS, MS, and SS) and soybean varieties (GQ8, GX7, ND25, and NN996) were conducted in 2021 and 2022. Results showed that growth recovery in the IS resulted in a balance in the expression of TERMINAL FLOWER 1 (TFL1) and FLOWERING LOCUS T (FT) in the meristematic tissues of soybeans, which promoted the formation of new branches or flowers. IS prolonged the flowering time (2-7 days) and increased the number of forming flowers compared with SS (93.0 and 169%) and MS (67.3 and 103.3%) at the later soybean flowering stage. The higher carbon and nitrogen content in the middle and bottom canopies of soybean contributed to decreased flower abscission by 26.7 and 30.2%, respectively, compared with SS. Canopy light environment recovery promoted branch and flower formation and transformation of flowers into pods with lower flower-pod abscission, which contributed to elevating soybean yields in late-maturing and multibranching varieties (ND25) in IS.


Assuntos
Flores , Glycine max , Luz , Zea mays , Glycine max/fisiologia , Glycine max/genética , Glycine max/crescimento & desenvolvimento , Zea mays/fisiologia , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Flores/fisiologia , Flores/genética , Flores/crescimento & desenvolvimento , Agricultura/métodos , Produção Agrícola/métodos , Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Produtos Agrícolas/crescimento & desenvolvimento
3.
Circulation ; 150(3): 215-229, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39008559

RESUMO

BACKGROUND: Dietary acculturation, or adoption of dominant culture diet by migrant groups, influences human health. We aimed to examine dietary acculturation and its relationships with cardiovascular disease (CVD), gut microbiota, and blood metabolites among US Hispanic and Latino adults. METHODS: In the HCHS/SOL (Hispanic Community Health Study/Study of Latinos), US exposure was defined by years in the United States (50 states and Washington, DC) and US nativity. A dietary acculturation pattern was derived from 14 172 participants with two 24-hour dietary recalls at baseline (2008-2011) using least absolute shrinkage and selection operator regression, with food groups as predictors of US exposure. We evaluated associations of dietary acculturation with incident CVD across ≈7 years of follow-up (n=211/14 172 cases/total) and gut microbiota (n=2349; visit 2, 2014 to 2017). Serum metabolites associated with both dietary acculturation-related gut microbiota (n=694) and incident CVD (n=108/5256 cases/total) were used as proxy measures to assess the association of diet-related gut microbiome with incident CVD. RESULTS: We identified an empirical US-oriented dietary acculturation score that increased with US exposure. Higher dietary acculturation score was associated with higher risk of incident CVD (hazard ratio per SD, 1.33 [95% CI, 1.13-1.57]), adjusted for sociodemographic, lifestyle, and clinical factors. Sixty-nine microbial species (17 enriched from diverse species, 52 depleted mainly from fiber-utilizing Clostridia and Prevotella species) were associated with dietary acculturation, driven by lower intakes of whole grains, beans, and fruits and higher intakes of refined grains. Twenty-five metabolites, involved predominantly in fatty acid and glycerophospholipid metabolism (eg, branched-chain 14:0 dicarboxylic acid** and glycerophosphoethanolamine), were associated with both diet acculturation-related gut microbiota and incident CVD. Proxy association analysis based on these metabolites suggested a positive relationship between diet acculturation-related microbiome and risk of CVD (r=0.70, P<0.001). CONCLUSIONS: Among US Hispanic and Latino adults, greater dietary acculturation was associated with elevated CVD risk, possibly through alterations in gut microbiota and related metabolites. Diet and microbiota-targeted interventions may offer opportunities to mitigate CVD burdens of dietary acculturation.


Assuntos
Aculturação , Doenças Cardiovasculares , Dieta , Microbioma Gastrointestinal , Hispânico ou Latino , Humanos , Masculino , Feminino , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etnologia , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto , Dieta/efeitos adversos , Fatores de Risco , Incidência
4.
Chem Rev ; 123(21): 12039-12104, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37870767

RESUMO

Kohn-Sham Density Functional Theory (KSDFT) is the most widely used electronic structure method in chemistry, physics, and materials science, with thousands of calculations cited annually. This ubiquity is rooted in the favorable accuracy vs cost balance of KSDFT. Nonetheless, the ambitions and expectations of researchers for use of KSDFT in predictive simulations of large, complicated molecular systems are confronted with an intrinsic computational cost-scaling challenge. Particularly evident in the context of first-principles molecular dynamics, the challenge is the high cost-scaling associated with the computation of the Kohn-Sham orbitals. Orbital-free DFT (OFDFT), as the name suggests, circumvents entirely the explicit use of those orbitals. Without them, the structural and algorithmic complexity of KSDFT simplifies dramatically and near-linear scaling with system size irrespective of system state is achievable. Thus, much larger system sizes and longer simulation time scales (compared to conventional KSDFT) become accessible; hence, new chemical phenomena and new materials can be explored. In this review, we introduce the historical contexts of OFDFT, its theoretical basis, and the challenge of realizing its promise via approximate kinetic energy density functionals (KEDFs). We review recent progress on that challenge for an array of KEDFs, such as one-point, two-point, and machine-learnt, as well as some less explored forms. We emphasize use of exact constraints and the inevitability of design choices. Then, we survey the associated numerical techniques and implemented algorithms specific to OFDFT. We conclude with an illustrative sample of applications to showcase the power of OFDFT in materials science, chemistry, and physics.

5.
Proc Natl Acad Sci U S A ; 119(27): e2115939119, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35763578

RESUMO

Positive magnetoresistance (PMR) and negative magnetoresistance (NMR) describe two opposite responses of resistance induced by a magnetic field. Materials with giant PMR are usually distinct from those with giant NMR due to different physical natures. Here, we report the unusual photomagnetoresistance in the van der Waals heterojunctions of WSe2/quasi-two-dimensional electron gas, showing the coexistence of giant PMR and giant NMR. The PMR and NMR reach 1,007.5% at -9 T and -93.5% at 2.2 T in a single device, respectively. The magnetoresistance spans over two orders of magnitude on inversion of field direction, implying a giant unidirectional magnetoresistance (UMR). By adjusting the thickness of the WSe2 layer, we achieve the maxima of PMR and NMR, which are 4,900,000% and -99.8%, respectively. The unique magnetooptical transport shows the unity of giant UMR, PMR, and NMR, referred to as giant bipolar unidirectional photomagnetoresistance. These features originate from strong out-of-plane spin splitting, magnetic field-enhanced recombination of photocarriers, and the Zeeman effect through our experimental and theoretical investigations. This work offers directions for high-performance light-tunable spintronic devices.NMR).

6.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35165195

RESUMO

Mg2GeO4 is important as an analog for the ultrahigh-pressure behavior of Mg2SiO4, a major component of planetary interiors. In this study, we have investigated magnesium germanate to 275 GPa and over 2,000 K using a laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction and density functional theory (DFT) computations. The experimental results are consistent with the formation of a phase with disordered Mg and Ge, in which germanium adopts eightfold coordination with oxygen: the cubic, Th3P4-type structure. DFT computations suggest partial Mg-Ge order, resulting in a tetragonal [Formula: see text] structure indistinguishable from [Formula: see text] Th3P4 in our experiments. If applicable to silicates, the formation of this highly coordinated and intrinsically disordered phase may have important implications for the interior mineralogy of large, rocky extrasolar planets.

7.
Proc Natl Acad Sci U S A ; 119(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34969863

RESUMO

Light elements in Earth's core play a key role in driving convection and influencing geodynamics, both of which are crucial to the geodynamo. However, the thermal transport properties of iron alloys at high-pressure and -temperature conditions remain uncertain. Here we investigate the transport properties of solid hexagonal close-packed and liquid Fe-Si alloys with 4.3 and 9.0 wt % Si at high pressure and temperature using laser-heated diamond anvil cell experiments and first-principles molecular dynamics and dynamical mean field theory calculations. In contrast to the case of Fe, Si impurity scattering gradually dominates the total scattering in Fe-Si alloys with increasing Si concentration, leading to temperature independence of the resistivity and less electron-electron contribution to the conductivity in Fe-9Si. Our results show a thermal conductivity of ∼100 to 110 W⋅m-1⋅K-1 for liquid Fe-9Si near the topmost outer core. If Earth's core consists of a large amount of silicon (e.g., > 4.3 wt %) with such a high thermal conductivity, a subadiabatic heat flow across the core-mantle boundary is likely, leaving a 400- to 500-km-deep thermally stratified layer below the core-mantle boundary, and challenges proposed thermal convection in Fe-Si liquid outer core.

8.
BMC Med ; 22(1): 200, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38755647

RESUMO

BACKGROUND: Osteosarcoma (OS) is the most common primary malignant bone tumor and is highly prone to metastasis. OS can metastasize to the lymph node (LN) through the lymphatics, and the metastasis of tumor cells reestablishes the immune landscape of the LN, which is conducive to the growth of tumor cells. However, the mechanism of LN metastasis of osteosarcoma and remodeling of the metastatic lymph node (MLN) microenvironment is not clear. METHODS: Single-cell RNA sequencing of 18 samples from paracancerous, primary tumor, and lymph nodes was performed. Then, new signaling axes closely related to metastasis were identified using bioinformatics, in vitro experiments, and immunohistochemistry. The mechanism of remodeling of the LN microenvironment in tumor cells was investigated by integrating single-cell and spatial transcriptomics. RESULTS: From 18 single-cell sequencing samples, we obtained 117,964 cells. The pseudotime analysis revealed that osteoblast(OB) cells may follow a differentiation path from paracancerous tissue (PC) → primary tumor (PT) → MLN or from PC → PT, during the process of LN metastasis. Next, in combination of bioinformatics, in vitro and in vivo experiments, and immunohistochemistry, we determined that ETS2/IBSP, a new signal axis, might promote LN metastasis. Finally, single-cell and spatial dissection uncovered that OS cells could reshape the microenvironment of LN by interacting with various cell components, such as myeloid, cancer-associated fibroblasts (CAFs), and NK/T cells. CONCLUSIONS: Collectively, our research revealed a new molecular mechanism of LN metastasis and clarified how OS cells influenced the LN microenvironment, which might provide new insight for blocking LN metastasis.


Assuntos
Neoplasias Ósseas , Linfonodos , Metástase Linfática , Osteossarcoma , Análise de Célula Única , Transcriptoma , Microambiente Tumoral , Osteossarcoma/patologia , Osteossarcoma/genética , Humanos , Neoplasias Ósseas/patologia , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Linfonodos/patologia , Metástase Linfática/patologia , Animais , Camundongos , Linhagem Celular Tumoral , Perfilação da Expressão Gênica
9.
BMC Cancer ; 24(1): 496, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637761

RESUMO

Ferroptosis has important value in cancer treatment. It is significant to explore the new ferroptosis-related lncRNAs prediction model in Hepatocellular carcinoma (HCC) and the potential molecular mechanism of ferroptosis-related lncRNAs. We constructed a prognostic multi-lncRNA signature based on ferroptosis-related differentially expressed lncRNAs in HCC. qRT-PCR was applied to determine the expression of lncRNA in HCC cells. The biological roles of NRAV in vitro and in vivo were determined by performing a series of functional experiments. Furthermore, dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to confirm the interaction of NRAV with miR-375-3P. We identified 6 differently expressed lncRNAs associated with the prognosis of HCC. Kaplan-Meier analyses revealed the high-risk lncRNAs signature associated with poor prognosis of HCC. Moreover, the AUC of the lncRNAs signature showed utility in predicting HCC prognosis. Further functional experiments show that the high expression of NRAV can strengthen the viciousness of HCC. Interestingly, we found that NRAV can enhance iron export and ferroptosis resistance. Further study showed that NRAV competitively binds to miR-375-3P and attenuates the inhibitory effect of miR-375-3P on SLC7A11, affecting the prognosis of patients with HCC. In conclusion, We developed a novel ferroptosis-related lncRNAs prognostic model with important predictive value for the prognosis of HCC. NRAV is important in ferroptosis induction through the miR-375-3P/SLC7A11 axis.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , MicroRNAs , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/genética , RNA Longo não Codificante/genética , Ferroptose/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Prognóstico , Sistema y+ de Transporte de Aminoácidos/genética
10.
J Org Chem ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38939958

RESUMO

A photo-induced cascade sulfone alkylation/cyclization of 2-isocyanoaryl thioethers is explored. This visible-light-triggered reaction not only occurs under extremely mild reaction conditions but also does not require the presence of a photosensitizer. The photocatalytic process is triggered by the photochemical activity of in situ-generated electron donor-acceptor complexes, arising from the association of 2-isocyanoaryl thioethers and α-iodosulfones. The radical pathway was confirmed by UV-vis spectroscopy, radical trapping, Job's plot, and on/off irradiation experiments.

11.
Fish Shellfish Immunol ; 147: 109436, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369071

RESUMO

IFN-γ plays a crucial role in both innate and adaptive immune responses and is a typical Th1 cytokine that promotes Th1 response and activates macrophages. When macrophages were incubated with IFN-γ, their phagocytosis ratio against Mycobacterium marinum increased significantly, as observed under fluorescence microscopy. The macrophages engulfed a large number of M. marinum. The proliferative ability of macrophages treated with IFN-γ was significantly weaker on the 4th and 7th day after phagocytosis and subsequent re-infection with marine chlamydia (P < 0.001). This suggests that IFN-γ enhances the phagocytosis and killing ability of macrophages against M. marinum. IFN-γ protein also significantly increased the production of reactive oxygen species (H2O2) and nitric oxide (NO) by macrophages. Additionally, the expression levels of toll-like receptor 2 (tlr2) and caspase 8 (casp8) were significantly higher in macrophages after IFN-γ incubation compared to direct infection after 12 h of M. marinum stimulation. Apoptosis was also observed to a higher degree in IFN-γ incubated macrophage. Moreover, mRNA expression of major histocompatibility complex (MHC) molecules produced by macrophages after IFN-γ incubation was significantly higher than direct infection. This indicates that IFN-γ enhances antigen presentation by upregulating MHC expression. It also upregulates tlr2 and casp8 expression through the TLR2 signaling pathway to induce apoptosis in macrophages. The pro-inflammatory cytokine showed an initial increase followed by a decline, suggesting that IFN-γ enhances the immune response of macrophages against M. marinum infection. On the other hand, the anti-inflammatory cytokine showed a delayed increase, significantly reducing the expression of pro-inflammatory cytokines. The expression of both cytokines balanced each other and together regulated the inflammatory reaction against M. marinum infection.


Assuntos
Mycobacterium marinum , Receptor 2 Toll-Like , Animais , Receptor 2 Toll-Like/genética , Peróxido de Hidrogênio/metabolismo , Macrófagos , Citocinas/metabolismo
12.
Fish Shellfish Immunol ; 144: 109240, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38008344

RESUMO

Teleost fish possess a diversity of type Ⅰ interferons (IFNs) repertoire, which play a crucial role in antiviral and antimicrobial immune responses. In our previous study, IFNe1-3 and IFNb were identified and cloned from Chinese sturgeon (Acipenser sinensis), an acipenseriform fish. However, the absence of Chinese sturgeon genome data has left the question of whether there are other type Ⅰ IFN members in this species unresolved. In this study, we have identified and characterized a novel IFN, IFNf in Chinese sturgeon (AsIFNf). Bioinformatics analysis revealed that the AsIFNf contains a unique disulfide bond (2 cysteines) located in the second exon and fifth exon region, distinguishing it from other reported teleost type I IFNs. Meanwhile, qPCR results showed that AsIFNf mRNA was detectable in all examined tissues and up-regulated in the spleen or kidney in response to poly I: C, Citrobacter freundii, and Spring Viremia of Carp Virus (SVCV), but not by LPS. Furthermore, compared to recombinant AsIFNe2 protein (rAsIFNe2), rAsIFNf exhibited a stronger protective effect on Chinese sturgeon fin cells against SVCV and also induced higher expression of antiviral genes Mx and viperin. Importantly, AsIFNf displayed characteristics similar to antimicrobial peptides (AMPs) with a positive charge and demonstrated a broad spectrum of antimicrobial activity in vitro. These findings provide a theoretical foundation for understanding the primitive structure and function of interferon, as well as deepening our comprehension of the innate immune system and disease defense in the endangered Chinese sturgeon.


Assuntos
Anti-Infecciosos , Doenças dos Peixes , Interferon Tipo I , Animais , Filogenia , Peixes/genética , Interferon Tipo I/genética , Antivirais/farmacologia
13.
Environ Sci Technol ; 58(27): 12167-12178, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38920332

RESUMO

Herein, we propose preferential dissolution paired with Cu-doping as an effective method for synergistically modulating the A- and B-sites of LaMnO3 perovskite. Through Cu-doping into the B-sites of LaMnO3, specifically modifying the B-sites, the double perovskite La2CuMnO6 was created. Subsequently, partial La from the A-sites of La2CuMnO6 was etched using HNO3, forming novel La2CuMnO6/MnO2 (LCMO/MnO2) catalysts. The optimized catalyst, featuring an ideal Mn:Cu ratio of 4.5:1 (LCMO/MnO2-4.5), exhibited exceptional catalytic ozonation performance. It achieved approximately 90% toluene degradation with 56% selectivity toward CO2, even under ambient temperature (35 °C) and a relatively humid environment (45%). Modulation of A-sites induced the elongation of Mn-O bonds and decrease in the coordination number of Mn-O (from 6 to 4.3) in LCMO/MnO2-4.5, resulting in the creation of abundant multivalent Mn and oxygen vacancies. Doping Cu into B-sites led to the preferential chemisorption of toluene on multivalent Cu (Cu(I)/Cu(II)), consistent with theoretical predictions. Effective electronic supplementary interactions enabled the cycling of multiple oxidation states of Mn for ozone decomposition, facilitating the production of reactive oxygen species and the regeneration of oxygen vacancies. This study establishes high-performance perovskites for the synergistic regulation of O3 and toluene, contributing to cleaner and safer industrial activities.


Assuntos
Ozônio , Tolueno , Catálise , Ozônio/química , Tolueno/química , Titânio/química , Óxidos/química , Compostos de Cálcio/química
14.
Environ Sci Technol ; 58(11): 5103-5116, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38445973

RESUMO

Organic light-emitting materials (OLEMs) are emerging contaminants in the environment and have been detected in various environment samples. However, limited information is available regarding their contamination within the human body. Here, we developed a novel QuEChERS (quick, easy, cheap, effective, rugged, and safe) method coupled with triple quadrupole/high-resolution mass spectrometry to determine OLEMs in breast milk samples, employing both target and suspect screening strategies. Our analysis uncovered the presence of seven out of the 39 targeted OLEMs in breast milk samples, comprising five liquid crystal monomers and two OLEMs commonly used in organic light-emitting diode displays. The cumulative concentrations of the seven OLEMs in each breast milk sample ranged from ND to 1.67 × 103 ng/g lipid weight, with a mean and median concentration of 78.76 and 0.71 ng/g lipid weight, respectively, which were higher compared to that of typical organic pollutants such as polychlorinated biphenyls and polybrominated diphenyl ethers. We calculated the estimated daily intake (EDI) rates of OLEMs for infants aged 0-12 months, and the mean EDI rates during lactation were estimated to range from 30.37 to 54.89 ng/kg bw/day. Employing a suspect screening approach, we additionally identified 66 potential OLEMs, and two of them, cholesteryl hydrogen phthalate and cholesteryl benzoate, were further confirmed using pure reference standards. These two substances belong to cholesteric liquid crystal materials and raise concerns about potential endocrine-disrupting effects, as indicated by in silico predictive models. Overall, our present study established a robust method for the identification of OLEMs in breast milk samples, shedding light on their presence in the human body. These findings indicate human exposure to OLEMs that should be further investigated, including their health risks.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Lactente , Feminino , Humanos , Leite Humano/química , Poluentes Ambientais/análise , Bifenilos Policlorados/análise , Espectrometria de Massas , Lipídeos
15.
Plant Dis ; 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616400

RESUMO

Amorphophallus muelleri is an Araceae plant with perennial tuber, widely used in food, pharmaceutical and chemical industry due to its richness in glucomannan. In April 2022, an outbreak of a target spot on A. muelleri plantlets was observed in a nursery in Ruili, Yunnan, China. The leafstalks of the diseased plantlets in the nursery turned brown and decayed (Fig.1 A-B), then gradually some water-soaked spots on the true leaves developed along the veins (Fig.1 A). Subquencely, the spots on the true leaves turned dark green to white-grayish in the center, which formed light to dark brown concentric rings with a target-like appearance surrounded by a yellow halo (Fig.1 C). When the temperature was 20-34℃ and the relatively humidity was 25-80%, dark-green to black sporodochia with white hypha appeared on the lower and upper leaf surfaces. Finally, 5-8% of the plants surveyed on 800 m2 of one-year-old plantlets in the nursery showed the symptoms and some plants with infected leafstalks would be death. Similar symptoms were also observed on about 10% of the transplanted plants surveyed on 12000 m2 (1.2 ha) of two-year-old plantlets in the field. Five diseased leaves from five distinct plantlets in the nursery were collected for pathogen isolation. Leaf pieces(5 x 5 mm) were cut from the edge of necrotic lesions, and surface-sterilized with 2.5% sodium hypochlorite for 1 min, 75% ethanol for 30 s, then rinsed 5 times by sterilized distilled water, finally put the leaf pieces on sterilized filter paper for 3-5 minutes to dry them and transferred onto potato dextrose agar (PDA) in petri dishes at 25℃ for three days. Five pure cultures identical to colony and conidial characteristics were isolated from five individual plants. The representative pure culture (M1) was grayish-white and circular colonies were 7.50 cm in diamter after 15 days at 25℃, with dark green concentric rings of sporodochia, the dorsal view of the colonies were yellowish. Conidia were aseptate, smooth, cylindrical, 5.00-6.25 (5.71) x 1.25-1.67 (1.63) µm (n = 20) rounded at both ends. A spore suspension (1 x 106 spores/ml) was prepared by harvesting spores from 15-day-old cultures grown in the dark at 25℃, then a thirty-ml of spore suspension was sprayed on the healthy leaves of 10 two-year-old plantlets. Thirty-ml of sterile water was sprayed on the healthy leaves of another 10 seedlings and used as the control. All seedlings were placed in a nursery at 20 to 34℃ and a relative humidity of 25 to 80%. Similar symptoms (Fig.1 D-F) to those observed in the nursery and field developed on all the 10 seedlings inoculated with M1 after two days, but not on the control leaves. The pathogenicity tests were repeated for three times. Fungal cultures reisolated from the infected leaves were identical to the original colonies and conidia, completing Koch's postulates. The internal transcribed spacer (ITS, primers ITS1 and ITS4) region of ribosomal DNA (OQ553785), calmodulin (cmdA, primers CAL-228F and CAL2Rd)(OQ559103), RNA polymerase II second largest subunit (rpb2, primers RPB2-5F2 and RPB2-7cR) (OQ559104) and ß-tubulin (tub2, primers Bt2a and Bt2b) (OQ559105) of M1 had 100%, 98.52%, 98.98% and 98.98% identity with the sequences of Paramyrothecium breviseta CBS544.75 (KU846289 for ITS, KU846262 for cmdA, KU846351 for rpb2, and KU846406 for tub2), respectively. In the phylogenic tree based on ITS, cmdA, rpb2 and tub2 gene sequences, the pure culture M1 clustered with P. breviseta CBS544.75, SDBR-CMU387, DRL4 and DRL3, which has been reported as the pathogen of leaf spot of Coffea arabica in China, C. canephora in China and Thailand (Wu et al. 2021; Withee et al. 2022). Molecular and morphological observations showed the pure culture M1 were P. breviseta (Withee et al. 2022), in addition the disease was named as target spot dueing to the typical target symptom on the leaves. To our knowledge, this is the first report of P. breviseta on A. muelleri from Yunnan, China, as well as worldwide. This disease can caused serious economic losses of A. muelleri dueing to that it can result 5-8% death of the plants in the nursery.

16.
Int J Mol Sci ; 25(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39000433

RESUMO

Drought presents a significant abiotic stress that threatens crop productivity worldwide. Rhizosphere bacteria play pivotal roles in modulating plant growth and resilience to environmental stresses. Despite this, the extent to which rhizosphere bacteria are instrumental in plant responses to drought, and whether distinct cassava (Manihot esculenta Crantz) varieties harbor specific rhizosphere bacterial assemblages, remains unclear. In this study, we measured the growth and physiological characteristics, as well as the physical and chemical properties of the rhizosphere soil of drought-tolerant (SC124) and drought-sensitive (SC8) cassava varieties under conditions of both well-watered and drought stress. Employing 16S rDNA high-throughput sequencing, we analyzed the composition and dynamics of the rhizosphere bacterial community. Under drought stress, biomass, plant height, stem diameter, quantum efficiency of photosystem II (Fv/Fm), and soluble sugar of cassava decreased for both SC8 and SC124. The two varieties' rhizosphere bacterial communities' overall taxonomic structure was highly similar, but there were slight differences in relative abundance. SC124 mainly relied on Gamma-proteobacteria and Acidobacteriae in response to drought stress, and the abundance of this class was positively correlated with soil acid phosphatase. SC8 mainly relied on Actinobacteria in response to drought stress, and the abundance of this class was positively correlated with soil urease and soil saccharase. Overall, this study confirmed the key role of drought-induced rhizosphere bacteria in improving the adaptation of cassava to drought stress and clarified that this process is significantly related to variety.


Assuntos
Secas , Manihot , Rizosfera , Microbiologia do Solo , Estresse Fisiológico , Manihot/microbiologia , Bactérias/classificação , Bactérias/genética , RNA Ribossômico 16S/genética , Microbiota , Raízes de Plantas/microbiologia , Solo/química
17.
J Sci Food Agric ; 104(7): 3865-3882, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38217341

RESUMO

BACKGROUND: Soil is a key foundation of crop root growth. There are interactions between root system and soil in multiple ways. The present study aimed to further explore the response of root distribution and morphology to soil physical and chemical environment under maize (Zea mays L.) soybean (Glycine Max L. Merr.) relay strip intercropping (MS) An experiment was carried out aiming to examine the effects of nitrogen (N) applications and interspecific distances on root system and soil environment in MS. The two N application levels, referred to as no N application (NN) and conventional N application (CN), were paired with different interspecific distances: 30, 45 and 60 cm (MS30, MS45 and MS60) and 100 cm of monoculture maize and soybean (MM/SS100). RESULTS: The results demonstrated that MS45 increased the distribution of soil aggregates (> 2 mm) near the crop roots and maize soil nutrients status, which increased by 20.3% and 15.6%. Meanwhile, MS reduced soil bulk density, increased soil porosity and improved soil oxygen content. Optimization of the soil environment facilitated root growth. The MS45 achieved a better result on root distribution and morphology than the other configuration and also increased land productivity. CONCLUSION: Relay intercropped soybean with maize in interspecific row spacing of 45 cm, improved soil physicochemical environment, reshaped root architecture and optimized root spatial distribution of crops to achieve greater land productivity. © 2024 Society of Chemical Industry.


Assuntos
Agricultura , Solo , Solo/química , Agricultura/métodos , Glycine max , Zea mays , Nitrogênio/análise
18.
J Sci Food Agric ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980001

RESUMO

BACKGROUND: Relay intercropping of maize and soybean can improve land productivity. However, the mechanism behind N2O emissions in this practice remains unclear. A two-factor randomized block field trial was conducted to reveal the mechanism of N2O emissions in a full additive maize-soybean relay intercropping. Factor A was three cropping systems - that is, monoculture maize (Zea mays L.), monoculture soybean (Glycine max L. Merr.) and maize-soybean relay intercropping. Factor B was different N supply, containing no N, reduced N and conventional N. Differences in N2O emissions, soil properties, rhizosphere bacterial communities and yield advantage were evaluated. RESULTS: The land equivalent ratio was 1.55-2.44, and the cumulative N2O emission ( C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ ) was notably lower by 60.2% in intercropping than in monoculture, respectively. Reduced N declined C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ without penalty on the yield advantages. The relay intercropping shifted soil properties - for example, soil organic matter, total N, NH 4 + $$ {\mathrm{NH}}_4^{+} $$ and protease activity - and improved the soil microorganism community - for example, Proteobacteria and Acidobacteria. Intercropping reduced C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ by directly suppressing nirS- and amoA-regulated N2O generation during soil N cycling, or nirS- and amoA-mediated soil properties shifted to reduce C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ indirectly. Reduced N directly reduced C E N 2 O $$ \mathrm{C}{\mathrm{E}}_{{\mathrm{N}}_2\mathrm{O}} $$ by decreasing soil N content and reducing soil microorganism activities to alleviate N2O produced in soil N cycling. CONCLUSION: Conducting a full additive maize-soybean relay intercropping with reduced nitrogen supply provides a way to alleviate N2O emissions without the penalty on the yield advantage by changing rhizosphere bacterial communities and soil N cycling. © 2024 Society of Chemical Industry.

19.
J Am Chem Soc ; 145(35): 19164-19170, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37610128

RESUMO

A ZnII8L6 pseudocube containing anthracene-centered ligands, a ZnII4L'4 tetrahedron with a similar side length as the cube, and a trigonal prism ZnII6L3L'2 were formed in equilibrium from a common set of subcomponents. Hetero-Diels-Alder reaction with photogenerated singlet oxygen transformed the anthracene-containing "L" ligands into endoperoxide "LO" ones and ultimately drove the integrative self-sorting to form the trigonal prismatic cage ZnII6LO3L'2 exclusively. This ZnII6LO3L'2 structure lost dioxygen in a retro-Diels-Alder reaction after heating, which resulted in reversion to the initial ZnII8L6 + ZnII4L'4 ⇌ 2 × ZnII6L3L'2 equilibrating system. Whereas the ZnII8L6 pseudocube had a cavity too small for guest encapsulation, the ZnII6L3L'2 and ZnII6LO3L'2 trigonal prisms possessed peanut-shaped internal cavities with two isolated compartments divided by bulky anthracene panels. Guest binding was also observed to drive the equilibrating system toward exclusive formation of the ZnII6L3L'2 structure, even in the absence of reaction with singlet oxygen.

20.
Cancer Sci ; 114(7): 3014-3026, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37150900

RESUMO

Osteoclasts (OCs) and regulatory CD4+ T cells (CD4+ Tregs) are important components in the tumor microenvironment (TME) of osteosarcoma. In this study, we collected six osteosarcoma samples from our previous study (GSE162454). We also integrated a public database (GSE152048), which included single cell sequencing data of 11 osteosarcoma patients. We obtained 138,192 cells and then successfully identified OCs and CD4+ Tregs. Based on the interaction gene set between OCs and CD4+ Tregs, patients from GSE21257 were distinguished into two clusters by consensus clustering analysis. Both the tumor immune microenvironment and survival prognosis between the two clusters were significantly different. Subsequently, five model genes were identified by protein-protein interaction network based on differentially upregulated genes of cluster 2. Quantitative RT-PCR was used to detect their expression in human osteoblast and osteosarcoma cells. A prognostic model was successfully established using these five genes. Kaplan-Meier survival analysis found that patients in the high-risk group had worse survival (p = 0.029). Therefore, our study first found that cell-cell communication between OCs and CD4+ Tregs significantly alters TME and is connected to poor prognosis of OS. The model we constructed can accurately predict prognosis for osteosarcoma patients.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Osteoclastos , Linfócitos T , Osteossarcoma/genética , Prognóstico , Microambiente Tumoral/genética , Neoplasias Ósseas/genética , Linfócitos T CD4-Positivos
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