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1.
Article in English | MEDLINE | ID: mdl-38780584

ABSTRACT

Four yeast strains belonging to the basidiomycetous yeast genus Mrakia were isolated from diverse habitats in the Ny-Ålesund region (Svalbard, High Arctic): two from vascular plants, one from seawater and one from freshwater. Phylogenetic analysis, based on the ITS region and the D1/D2 domain of the 28S rRNA gene, identified these four strains as representing two novel species within the genus Mrakia. The names Mrakia polaris sp. nov. (MycoBank number: MB 852063) and Mrakia amundsenii sp. nov. (MycoBank number: MB 852064) are proposed. These two new species show distinct psychrophilic adaptations, as they exhibit optimal growth at temperatures between 10 and 15°C, while being unable to grow at 25°C. The holotype of M. polaris sp. nov. is CPCC 300345T, and the holotype of M. amundsenii sp. nov. is CPCC 300572T.


Subject(s)
DNA, Fungal , Phylogeny , Seawater , Sequence Analysis, DNA , Arctic Regions , DNA, Fungal/genetics , Seawater/microbiology , Mycological Typing Techniques , Svalbard , RNA, Ribosomal, 28S/genetics , Basidiomycota/genetics , Basidiomycota/classification , Basidiomycota/isolation & purification , Fresh Water/microbiology , Ecosystem , Cold Temperature , Saccharomycetales/classification , Saccharomycetales/genetics , Saccharomycetales/isolation & purification
2.
J Antibiot (Tokyo) ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38745102

ABSTRACT

Four new echinomycin congeners, quinomycins M-P (1-4) were isolated from the cultures of the soil-derived Streptomyces sp. CPCC205575. The planar structures were determined by comprehensive analyses of NMR and HRESIMS/MS data. The absolute configurations were elucidated by the advanced Marfey's method combined with biosynthetic gene analysis. Compounds 1-4 represent the first examples of quinomycin-type natural products with the sulfur atom at the N,S-dimethylcysteine residue oxidized as a sulfoxide group forming the unusual N-methyl-3-methylsulfinyl-alanine residue. Bioassay results revealed that the oxidation of the sulfur atom at the Cys or Cys' residues led to dramatic decrease of cytotoxicity and antimicrobial activity.

3.
Small ; : e2309499, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38624172

ABSTRACT

Various semiconductor devices have been developed based on 2D heterojunction materials owing to their distinctive optoelectronic properties. However, to achieve efficient charge transfer at their interface remains a major challenge. Herein, an alloy heterojunction concept is proposed. The sulfur vacancies in ZnIn2S4 are filled with selenium atoms of PdSe2. This chemically bonded heterojunction can significantly enhance the separation of photocarriers, providing notable advantages in the field of photoelectric conversion. As a demonstration, a two-terminal photodetector based on the PdSe2/ZnIn2S4 heterojunction materials is fabricated. The photodetector exhibits stable operation in ambient conditions, showcasing superior performance in terms of large photocurrent, high responsivity (48.8 mA W-1) and detectivity (1.98 × 1011 Jones). To further validate the excellent optoelectronic performance of the heterojunction, a tri-terminal phototransistor is also fabricated. Benefiting from gate voltage modulation, the photocurrent is amplified to milliampere level, and the responsivity is increased to 229.14 mA W-1. These findings collectively demonstrate the significant potential of the chemically bonded PdSe2/ZnIn2S4 alloy heterojunction for future optoelectronic applications.

4.
Gland Surg ; 13(2): 199-208, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38455344

ABSTRACT

Background: Breast cancer has become the most frequently diagnosed cancer in the world. Detection at an early stage, frequently allows women to benefit from breast conserving surgery. However, some patients are not satisfied with the breast shape after breast-conserving surgery, and autologous tissue flaps are needed to fill the defect in the resection area. The modified lateral thoracic artery perforator (LTAP) flap isn't one of the commonly used flaps in breast surgery and has the advantages of a reliable blood supply, simple operation and few postoperative complications. In this study, we aimed to evaluate the feasibility and effectiveness of a modified LTAP flap for repairing partial breast defects after breast-conserving surgery. Methods: In this study, we retrospectively analyzed the clinical data of 126 patients treated with LTAP flaps to repair local breast defects at Affiliated Hospital of Guangdong Medical University between January 2020 and June 2021. Data were collected on the demographic characteristics of these patients, tumor size and location, type of axillary lymph node surgery, availability of adjuvant chemotherapy and radiotherapy, and postoperative complications. Results: The median weight of the tumor specimen was 185 g (range, 170-320 g), and this glandular tissue accounted for 30% to 40% of the total breast volume. The average flap size was 10.5 cm ×2.5 cm (length range, 8-15 cm, width range: 2-4 cm). The minimum follow-up time was 6 months, with an average of 10 months (range, 6-22 months). The mean operative time was 130 minutes (range: 90-180 minutes), and the mean hospital stay was 3 days (range, 2-5 days). All modified LTAP flaps survived completely without donor site complications. None of the patients required revision surgery on the postoperative breast. Conclusions: The modified LTAP flap is a reliable method for repairing partial breast defects after breast-conserving surgery. It has the advantages of a simple operation, a reliable blood supply, fewer postoperative complications, and a high flap survival rate. It is especially suitable for Asian women with small breast volumes and can achieve good breast contouring effects.

5.
J Exp Child Psychol ; 242: 105891, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38442684

ABSTRACT

This study aimed to investigate the longitudinal association between theory of mind (ToM) and loneliness as well as the potential moderating effects of parenting style on this association. A total of 689 Chinese third-grade students (341 girls and 348 boys; Mage = 9.23 years, SD = 0.66) were recruited from eight primary schools and were followed from Grade 3 to Grade 5. These students reported their primary caregivers' parenting style in third grade and completed the same ToM task and loneliness questionnaire at each time point from Grade 3 to Grade 5. The study's results indicated a bidirectional relationship between ToM and loneliness, implying that children with less developed ToM abilities tend to feel lonelier and, conversely, that higher levels of loneliness are associated with lower ToM skills. Moreover, the study demonstrated that parenting style influenced the association between ToM and loneliness. Specifically, the impact of ToM at Grade 3 on reducing loneliness at Grade 4 was greater among children who experienced high levels of rejection from their caregivers compared with those with low levels of rejection. In addition, this study found that loneliness at Grade 3 had a greater influence on ToM at Grade 5 for children experiencing low levels of emotional warmth from their caregivers than for those who experienced high levels of emotional warmth. These findings highlight the significance of ToM as both a precursor and consequence of children's loneliness and emphasize the variation in these longitudinal relationships based on the parenting styles of primary caregivers.


Subject(s)
Loneliness , Theory of Mind , Male , Child , Female , Humans , Loneliness/psychology , Students , Parenting/psychology , Schools
6.
RSC Adv ; 14(12): 8260-8263, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38469195

ABSTRACT

A new linear thiopeptide, bernitrilecin (1), was isolated from Streptomyces sp. CPCC 203702. Compound 1 is the first example of a nitrile-bearing thiopeptide. Its structure and absolute configuration were elucidated by extensive analysis of spectroscopic data and Marfey's method. The biosynthesis of the nitrile unit for 1 was proposed to be through oxidations, decarboxylation, and dehydration. Compound 1 exhibited significant anti-influenza A virus activity with the IC50 value of 16.7 µM.

7.
Org Lett ; 26(1): 1-5, 2024 01 12.
Article in English | MEDLINE | ID: mdl-37988124

ABSTRACT

Two previous unreported epipolythiodioxopiperazines of the emestrin family, namely, noremestrin A (1) and secoemestrin E (2), were successfully isolated from the fungal source Emericella sp. 1454. Employing comprehensive spectroscopic techniques, such as high-resolution electrospray ionization mass spectrometry, infrared, and nuclear magnetic resonance (NMR), along with NMR and electronic circular dichroism calculations, the chemical structures of compounds 1 and 2 were elucidated. Particularly noteworthy is the distinctive nature of noremestrin A, representing the inaugural instance of a noremestrin variant incorporating a sulfur-bearing 15-membered macrocyclic lactone moiety. Compounds 1 and 2 exhibited weak cytotoxic activities against the human chronic myelocytic leukemia cell lines MEG-01 and K562.


Subject(s)
Antineoplastic Agents , Emericella , Humans , Lactones/chemistry , Emericella/chemistry , Magnetic Resonance Spectroscopy , Antineoplastic Agents/chemistry , Aspergillus , Circular Dichroism , Molecular Structure
8.
Front Microbiol ; 14: 1267771, 2023.
Article in English | MEDLINE | ID: mdl-38107860

ABSTRACT

Solirubrobacter spp. were abundant in soil samples collected from deserts and other areas with high UV radiation. In addition, a novel Solirubrobacter species, with strain CPCC 204708T as the type, was isolated and identified from sandy soil sample collected from the Badain Jaran Desert of the Inner Mongolia autonomous region. Strain CPCC 204708T was Gram-stain positive, rod-shaped, non-motile, non-spore-forming, and grew optimally at 28-30°C, pH 7.0-8.0, and in the absence of NaCl. Analysis of the 16S rRNA gene sequence of strain CPCC 204708T showed its identity within the genus Solirubrobacter, with highest nucleotide similarities (97.4-98.2%) to other named Solirubrobacter species. Phylogenetic and genomic analyses indicated that the strain was most closely related to Solirubrobacter phytolaccae KCTC 29190T, while represented a distinct species, as confirmed from physiological properties and comparison. The name Solirubrobacter deserti sp. nov. was consequently proposed, with CPCC 204708T (= DSM 105495T = NBRC 112942T) as the type strain. Genomic analyses of the Solirubrobacter spp. also suggested that Solirubrobacter sp. URHD0082 represents a novel species, for which the name Candidatus "Solirubrobacter pratensis" sp. nov. was proposed. Genomic analysis of CPCC 204708T revealed the presence of genes related to its adaptation to the harsh environments of deserts and may also harbor genes functional in plant-microbe interactions. Pan-genomic analysis of available Solirubrobacter spp. confirmed the presence of many of the above genes as core components of Solirubrobacter genomes and suggests they may possess beneficial potential for their associate plant and may be important resources for bioactive compounds.

9.
J Antibiot (Tokyo) ; 76(12): 728-730, 2023 12.
Article in English | MEDLINE | ID: mdl-37857884

ABSTRACT

Two new isocoumarin derivatives, eleuthemarins A (1) and B (2), were isolated from the Arctic fungus Eleutheromyces sp. CPCC 401592. Their structures and absolute configurations were elucidated through spectroscopic methods, quantum chemical calculations of NMR shifts, and calculated electronic circular dichroism. This is the first report for the chemical investigation of the genus Eleutheromyces. Compounds 1 and 2 showed selective cytotoxic activities against H460, A549, and HCT116 cancer cell lines with IC50 values in the range of 24.1-57.3 µM, respectively. Compound 1 displayed weak antibacterial activities.


Subject(s)
Ascomycota , Isocoumarins , Humans , Isocoumarins/pharmacology , Isocoumarins/chemistry , Anti-Bacterial Agents/chemistry , Magnetic Resonance Spectroscopy , HCT116 Cells , Molecular Structure
10.
Heliyon ; 9(10): e20819, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37867809

ABSTRACT

This study investigates the relationship between Chinese farmers' propensity to adopt environment-friendly practices and their membership in cooperatives. Based on data collected in 2021 from the Fujian China Household Survey, the Endogenous Switching Probit model (ESP) is applied to account for unobserved factors that could simultaneously affect farmers' cooperative membership and their willingness to adopt environment-friendly practices. First, the results indicate that a cooperative membership has a positive impact on the level of farmers' interest in green production practices. Second, there is evidence of some heterogeneity (based on both observable and unobservable characteristics) in the impact of cooperative membership; the higher the farmers' capital returns, the more prominent the role of cooperatives in guiding these farmers. Third, participation in cooperatives is conducive to raising farmers' interest in green production. The overall conclusion is that a cooperative membership raises the Chinese farmers' willingness to adopt environment-friendly practices.

11.
J Nat Prod ; 86(11): 2474-2486, 2023 11 24.
Article in English | MEDLINE | ID: mdl-37862150

ABSTRACT

Subplenones A-J (1-10), 10 new xanthone dimers, have been isolated and characterized from the endophytic fungus Subplenodomus sp. CPCC 401465, which resides within the Chinese medicinal plant Gentiana straminea. The isolation process was guided by antibacterial assays and molecular-networking-based analyses. The chemical structures of these compounds were elucidated through the interpretation of nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectrometry (HRESIMS) data. Furthermore, the relative configuration of the compounds was determined using NMR and single-crystal X-ray diffraction analyses, and the absolute configuration was established using electronic circular dichroism calculations. All of the isolated compounds exhibited significant inhibitory activity against Gram-positive bacteria. Notably, compounds 1, 5, and 7 displayed remarkable inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA) ATCC 700698, with a minimum inhibitory concentration (MIC) of 0.25 µg/mL, and against vancomycin-resistant Enterococcus faecium (VRE) ATCC 700221, with MIC values ranging from 0.5 to 1.0 µg/mL.


Subject(s)
Ascomycota , Methicillin-Resistant Staphylococcus aureus , Plants, Medicinal , Xanthones , Anti-Bacterial Agents/chemistry , Microbial Sensitivity Tests , Xanthones/pharmacology , Xanthones/chemistry , Molecular Structure
13.
J Antibiot (Tokyo) ; 76(10): 613-617, 2023 10.
Article in English | MEDLINE | ID: mdl-37402885

ABSTRACT

There are six new phthalide derivatives Verbalide A ~ F (1-6) together with another known derivative (7) isolated from the endophytic fungus Preussia sp. CPCC 400972. Their structures were established by comprehensive spectroscopic analyses, including NMR and HRESIMS. In addition, compounds 1-7 exhibited excellent inhibitory effect against influenza A virus.


Subject(s)
Ascomycota , Benzofurans , Molecular Structure , Ascomycota/chemistry , Benzofurans/pharmacology , Benzofurans/chemistry , Magnetic Resonance Spectroscopy
14.
Environ Res ; 233: 116437, 2023 09 15.
Article in English | MEDLINE | ID: mdl-37331553

ABSTRACT

In the Arctic fjords, the marine mycobiome experiences significant changes under environmental conditions driven by climate change. However, research on the ecological roles and the adaptive mechanisms of marine mycobiome in the Arctic fjord remains insufficiently explored. The present study employed shotgun metagenomics to comprehensively characterize the mycobiome in 24 seawater samples from Kongsfjorden, a High Arctic fjord situated in Svalbard. It revealed the presence of a diverse mycobiome with eight phyla, 34 classes, 71 orders, 152 families, 214 genera, and 293 species. The taxonomic and functional composition of the mycobiome differed significantly among the three layers, i.e., upper layer (depth of 0 m), middle layer (depths of 30-100 m), and lower layer (depths of 150-200 m). Several taxonomic groups (e.g., phylum Ascomycota, class Eurotiomycetes, order Eurotiales, family Aspergillaceae, and genus Aspergillus) and KOs (e.g., K03236/EIF1A, K03306/TC.PIT, K08852/ERN1, and K03119/tauD) were significantly distinct among the three layers. Among the measured environmental parameters, depth, NO2-, and PO43- were identified as the key factors influencing the mycobiome composition. Conclusively, our findings revealed that the mycobiome was diverse in the Arctic seawater and significantly impacted by the variability of environmental conditions in the High Arctic fjord. These results will assist future studies in exploring the ecological and adaptive responses towards the changes within the Arctic ecosystems.


Subject(s)
Mycobiome , Humans , Estuaries , Ecosystem , Svalbard , Metagenomics , Seawater , Arctic Regions
15.
Nat Commun ; 14(1): 3634, 2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37337012

ABSTRACT

Electrochemical conversion of nitrate to ammonia offers an efficient approach to reducing nitrate pollutants and a potential technology for low-temperature and low-pressure ammonia synthesis. However, the process is limited by multiple competing reactions and NO3- adsorption on cathode surfaces. Here, we report a Fe/Cu diatomic catalyst on holey nitrogen-doped graphene which exhibits high catalytic activities and selectivity for ammonia production. The catalyst enables a maximum ammonia Faradaic efficiency of 92.51% (-0.3 V(RHE)) and a high NH3 yield rate of 1.08 mmol h-1 mg-1 (at - 0.5 V(RHE)). Computational and theoretical analysis reveals that a relatively strong interaction between NO3- and Fe/Cu promotes the adsorption and discharge of NO3- anions. Nitrogen-oxygen bonds are also shown to be weakened due to the existence of hetero-atomic dual sites which lowers the overall reaction barriers. The dual-site and hetero-atom strategy in this work provides a flexible design for further catalyst development and expands the electrocatalytic techniques for nitrate reduction and ammonia synthesis.

16.
J Colloid Interface Sci ; 649: 685-693, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37385033

ABSTRACT

Constructing semiconductor heterojunctions can enable novel schemes for highly efficient photocatalytic activity. However, introducing strong covalent bonding at the interface remains an open challenge. Herein, ZnIn2S4 (ZIS) with abundant sulfur vacancies (Sv) is synthesized with the presence of PdSe2 as an additional precursor. The sulfur vacancies of Sv-ZIS are filled by Se atoms of PdSe2, leading to the Zn-In-Se-Pd compound interface. Our density functional theory (DFT) calculations reveal the increased density of states at the interface, which will increase the local carrier concentration. Moreover, the length of the Se-H bond is longer than that of the SH bond, which is good for the evolution of H2 from the interface. In addition, the charge redistribution at the interface results in a built-in field, providing the driving force for efficient separation of photogenerated electron-hole. Therefore, the PdSe2/Sv-ZIS heterojunction with strong covalent interface exhibits an excellent photocatalytic hydrogen evolution performance (4423 µmol g-1h-1) with an apparent quantum efficiency (λ > 420 nm) of 9.1 %. This work will provide new inspirations to improve photocatalytic activity by engineering the interfaces of semiconductor heterojunctions.

18.
Nat Prod Res ; : 1-7, 2023 May 08.
Article in English | MEDLINE | ID: mdl-37154381

ABSTRACT

Five isocoumarin derivatives including three new compounds, aspermarolides A-C (1-3), and two known analogues, 8-methoxyldiaporthin (4) and diaporthin (5) were obtained from the culture extract of Aspergillus flavus CPCC 400810. The structures of these compounds were elucidated by spectroscopic methods. The double bond geometry of 1 and 2 were assigned by the coupling constants. The absolute configuration of 3 was determined by electronic circular dichroism experiment. All compounds showed no cytotoxic activities against the two human cancer cells HepG2 and Hela.

19.
Opt Express ; 31(6): 10191-10200, 2023 Mar 13.
Article in English | MEDLINE | ID: mdl-37157572

ABSTRACT

Mn2+ doped lead-free double perovskites are emerging afterglow materials that can avoid the usage of rare earth ions. However, the regulation of the afterglow time is still a challenge. In this work, the Mn doped Cs2Na0.2Ag0.8InCl6 crystals with afterglow emission at about 600 nm are synthesized by a solvothermal method. Then, the Mn2+ doped double perovskite crystals are crushed into different sizes. As the size decreases from 1.7 mm to 0.075 mm, the afterglow time decreases from 2070 s to 196 s. Steady-state photoluminescence (PL) spectra, time resolved PL, thermoluminescence (TL) reveal the afterglow time monotonously decreases due to the enhanced nonradiative surface trapping. The modulation on afterglow time will greatly promote their applications in various fields, such as bioimaging, sensing, encryption, and anti-counterfeiting. As a proof of concept, dynamic display of information is realized based on different afterglow times.

20.
Front Pharmacol ; 14: 1184794, 2023.
Article in English | MEDLINE | ID: mdl-37251321

ABSTRACT

Peroxisome proliferator-activated receptors (PPARs) have been extensively studied for over 3 decades and consist of three isotypes, including PPARα, γ, and ß/δ, that were originally considered key metabolic regulators controlling energy homeostasis in the body. Cancer has become a leading cause of human mortality worldwide, and the role of peroxisome proliferator-activated receptors in cancer is increasingly being investigated, especially the deep molecular mechanisms and effective cancer therapies. Peroxisome proliferator-activated receptors are an important class of lipid sensors and are involved in the regulation of multiple metabolic pathways and cell fate. They can regulate cancer progression in different tissues by activating endogenous or synthetic compounds. This review emphasizes the significance and knowledge of peroxisome proliferator-activated receptors in the tumor microenvironment, tumor cell metabolism, and anti-cancer treatment by summarizing recent research on peroxisome proliferator-activated receptors. In general, peroxisome proliferator-activated receptors either promote or suppress cancer in different types of tumor microenvironments. The emergence of this difference depends on various factors, including peroxisome proliferator-activated receptor type, cancer type, and tumor stage. Simultaneously, the effect of anti-cancer therapy based on drug-targeted PPARs differs or even opposes among the three peroxisome proliferator-activated receptor homotypes and different cancer types. Therefore, the current status and challenges of the use of peroxisome proliferator-activated receptors agonists and antagonists in cancer treatment are further explored in this review.

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