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1.
Nat Prod Res ; : 1-6, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35014568

RESUMO

A facile synthesis of marine natural product smenodiol has been achieved in 23.2% overall yield within 8 steps from readily available starting materials, which facilitates a concise synthesis of the marine natural product (-)-pelorol by employing a TMSOTf-mediated Friedel-Crafts reaction with a methyl ester in the aryl as the key step.

2.
Quant Imaging Med Surg ; 12(1): 766-780, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34993117

RESUMO

Background: To systematically evaluate the physical image quality of low-dose computed tomography (LDCT) on CT scanners from 5 different manufacturers using a phantom model. Methods: CT images derived from a Catphan 500 phantom were acquired using manufacturer-specific iterative reconstruction (IR) algorithms and deep learning image reconstruction (DLIR) on CT scanners from 5 different manufacturers and compared using filtered back projection with 2 radiation doses of 0.25 and 0.75 mGy. Image high-contrast spatial resolution and image noise were objectively characterized by modulation transfer function (MTF) and noise power spectrum (NPS). Image high-contrast spatial resolution and image low-contrast detectability were compared directly by visual evaluation. CT number linearity and image uniformity were compared with intergroup differences using one-way analysis of variance (ANOVA). Results: The CT number linearity of 4 insert materials were as follows: acrylic (95% CI: 120.35 to 121.27; P=0.134), low-density polyethylene (95% CI: -98.43 to -97.43; P=0.070), air (95% CI: -996.16 to -994.51; P=0.018), and Teflon (95% CI: 984.40 to 986.87; P=0.883). The image uniformity values of GE Healthcare (95% CI: 3.24 to 3.83; P=0.138), Philips (95% CI: 2.62 to 3.70; P=0.299), Siemens (95% CI: 2.10 to 3.59; P=0.054), Minfound (95% CI: 2.35 to 3.65; P=0.589), and Neusoft (95% CI: 2.63 to 3.37; P=0.900) were evaluated and found to be within ±4 Hounsfield units (HU), with a range of 0.99-2.76 HU for standard deviations. There was no statistically significant difference in CT number linearity and image uniformity across the 5 CT scanners under different radiation doses with IR and DLIR algorithms (P>0.05). The resolution level at 10% MTF was 6.98 line-pairs-per-centimeter (lp/cm) on average, which was similar to the subjective evaluation results (mostly up to 7 lp/cm). DLIR at all 3 levels had the highest 50% MTF values among all reconstruction algorithms. For image low-contrast detectability, the minimum diameter of distinguishable contrast holes reached 4 mm at a 0.5% resolution. Increasing the radiation dose and IR strength reduced the image noise and NPS curve peak frequency while improving image low-contrast detectability. Conclusions: This study demonstrated that the image quality of CT scanners from 5 different manufacturers in LDCT is comparable and that the CT number linearity is unbiased and can contribute to accurate bone mineral density quantification.

3.
Biochem Genet ; 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34993722

RESUMO

Prostate cancer (PCa) is one of the most common and deadly cancers in men. The dysregulated circular RNAs (circRNAs) are involved in the development of various cancers, including PCa. The purpose of this study was to construct a circRNA-microRNA (miRNA)-mRNA network to explain the function of circ_0044516 in PCa. The expression analysis of circ_0044516, miR-330-5p, and sterile alpha and TIR motif-containing 1 (SARM1) was performed using real-time quantitative polymerase chain reaction, and the protein level of SARM1 was detected by western blot. The interaction between miR-330-5p and circ_0044516 or SARM1 obtained by bioinformatics prediction was verified by dual-luciferase reporter assay or RNA immunoprecipitation assay. For functional studies, cell proliferation was assessed by cell viability and colony formation ability using cell counting kit-8 assay and colony formation assay. Cell migration and invasion were studied using transwell assay. Cell apoptosis and cell cycle were investigated using flow cytometry assay. The tumorigenicity of circ_0044516 was tested by animal study. Circ_0044516 and SARM1 were highly expressed, while miR-330-5p was rarely expressed in PCa tissues and cells. Circ_0044516 acted as a miR-330-5p sponge to block miR-330-5p expression, and circ_0044516 knockdown suppressed PCa cell proliferation, migration, invasion, and cycle progression by enriching miR-330-5p. SARM1 was a target of miR-330-5p, and miR-330-5p restoration also inhibited PCa cell proliferation, migration, invasion, and cycle progression by degrading SARM1. Moreover, circ_0044516 deficiency blocked tumor growth in vivo by regulating the miR-330-5p/SARM1 axis. Circ_0044516 as a miR-330-5p sponge increases SARM1 expression, thus promoting the malignant development of PCa.

4.
Nat Prod Res ; : 1-9, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35007168

RESUMO

Three new aaptamines (1-3) together with two known derivatives (4-5) were isolated from the South China Sea sponge Aaptos suberitoides. The structures of all compounds were unambiguously elucidated by spectroscopic analyses as well as the comparison with literature data. All the compounds were evaluated for their cytotoxic activities against five human cancer cell lines including H1299, H520, SCG7901, CNE-2 and SW680 cells. As a result, compounds 3-5 showed moderate cytotoxicities against H1299 and H520 cells with IC50 values ranging from 12.9 to 20.6 µg/mL. Besides, compounds 3-5 also showed potent inhibitory activities toward cyclin-dependent kinase-2 (CDK2) with IC50 values of 14.3, 3.0 and 6.0 µg/mL, respectively. In addition, compounds 3-5 significantly induced G1 arrests of H1299 cells at low concentrations. Drug affinity responsive target stability (DARTS) experiments were carried out and further demonstrated that compound 3 could effectively bind with CDK2 protein and protect it from the degradation by pronase.

5.
PLoS Comput Biol ; 18(1): e1009762, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35007289

RESUMO

Activities of transcription factors (TFs) are temporally modulated to regulate dynamic cellular processes, including development, homeostasis, and disease. Recent developments of bioinformatic tools have enabled the analysis of TF activities using transcriptome data. However, because these methods typically use exon-based target expression levels, the estimated TF activities have limited temporal accuracy. To address this, we proposed a TF activity measure based on intron-level information in time-series RNA-seq data, and implemented it to decode the temporal control of TF activities during dynamic processes. We showed that TF activities inferred from intronic reads can better recapitulate instantaneous TF activities compared to the exon-based measure. By analyzing public and our own time-series transcriptome data, we found that intron-based TF activities improve the characterization of temporal phasing of cycling TFs during circadian rhythm, and facilitate the discovery of two temporally opposing TF modules during T cell activation. Collectively, we anticipate that the proposed approach would be broadly applicable for decoding global transcriptional architecture during dynamic processes.

6.
Neuropsychiatr Dis Treat ; 18: 11-18, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35018097

RESUMO

Background: Despite the best treatments, about 20% of patients with major depressive disorder (MDD) receiving drugs and psychological intervention show little or no improvement. There is no trial comparing different treatment methods in patients with anxiety/somatic subtype MDD. Aim: To compare the efficacy and safety of various treatments in patients with anxiety/somatic subtype MDD. Methods: This was a preliminary multicenter randomized controlled trial at eight participating hospitals in China (09/2016-06/2019) (ClinicalTrials.gov #NCT03219008). The patients were randomized to mirtazapine/SNRIs, mirtazapine/SNRIs+cognitive behavioral therapy (CBT), mirtazapine+SNRIs, or mirtazapine+SNRIs+physical therapies (modified electroconvulsive treatment or repetitive transcranial magnetic stimulation). The primary endpoint was the 17-item Hamilton Depression Scale (HAMD-17). The Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR) and Quality of Life (QOL)-6 were the secondary endpoints. The adverse events (AEs) were monitored. The patients were assessed at baseline (0 weeks), and at the end of the 2nd, 4th, 6th, 8th, and 12th week during treatment. Results: Finally, 107 patients were included: mirtazapine/SNRIs (n=36), mirtazapine/SNRIs+CBT (n=28), mirtazapine+SNRIs (n=29), and mirtazapine+SNRIs+physical therapies (n=14). The 17-HDRS and QIDS-SR scores decreased in all four groups, and the QOL-6 scores increased. There were no differences in the 17-HDRS (P=0.099), QIDS-SR (P=0.407), and QOL-6 (P=0.485) scores among the four groups. There were no differences in the occurrence of AEs among the four groups (P=0.942). Conclusion: This preliminary trial suggests that all four interventions (mirtazapine/SNRIs, mirtazapine/SNRIs+CBT, mirtazapine+SNRIs, or mirtazapine+SNRIs+physical therapies) achieved similar response and remission rates in patients with anxiety/somatic subtype MDD. The safety profile was manageable.

7.
J Food Sci ; 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-34997939

RESUMO

In this work, we investigated the effects of sucrose (0%-30%, w/w) on the pasting properties, retrogradation, freeze-thaw stability, texture, and the possible interaction with corn starch-tamarind seed polysaccharide (CS-TSP) mixtures. Sucrose increased the gelatinization temperature (from 76.4 ± 0.1 to 87.6 ± 0.0°C), peak viscosity (from 3358.0 ± 1.4 to 7732.5 ± 44.5 cP), and final viscosity (from 3514.0 ± 31.1 to 7724.5 ± 142.1 cP) of CS-TSP mixtures. Further, sucrose limited the increase in the storage modulus of the mixture pastes, transfer of bound water to free water, and water syneresis during the freeze-thaw process. Additionally, sucrose resulted in a more complete gel structure with stronger resistance. Scanning electron microscope and fluorescence labeling analysis showed that the presence of sucrose helped in tight entanglement or cross-link between amylose or between amylose and TSP. Thus, these results in this study could help to improve physicochemical properties of starch-based products, such as glue pudding and other starch desserts.

8.
Hum Cell ; 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35032297

RESUMO

Engineered T cells expressing chimeric antigen receptors (CARs) with tumor specificity have shown remarkable therapeutic effects on hematologic malignancies. However, CAR-T cells are less effective on solid tumors mainly due to the weak persistence of CAR-T cells, which might be caused by T cell death. Significant activation-induced cell death (AICD) of CAR-T cells was triggered by repeated antigen stimulation. AICD of T cell is characterized by the upregulation of death receptors and low persistence of T cells. Understanding the mechanism of AICD is crucial to improve the anti-tumor effect of CAR-T cells against solid tumors. Many approaches have been applied in CAR-T cell modification to enhance their anti-apoptosis ability. In this review, we summarized the molecular mechanisms of AICD in CAR-T cells and the progresses of anti-AICD in CAR-T cells therapy.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34989547

RESUMO

Intracellular delivery of functional molecules is of great importance in various biomedical and biotechnology applications. Recently, nanoparticle-based photothermal poration has attracted increasing attention because it provided a facile and efficient method to permeabilize cells transiently, facilitating the entry of exogenous molecules into cells. However, this method still has some safety concerns associated with the nanoparticles that bind to the cell membranes or enter the cells. Herein, a nanoplatform with both photothermal property and sugar-triggered cleaning ability for intracellular delivery is developed based on phenylboronic acid (PBA) functionalized porous magnetic nanoparticles (named as M-PBA). The M-PBA particles could bind to the target cells effectively through the specific interactions between PBA groups and the cis-diol containing components on the cell membrane. During a short-term near-infrared irradiation, the bound particles convert absorbed light energy to heat, enabling high-efficiency delivery of various exogenous molecules into the target cells via a photothermal poration mechanism. After delivery, the bound particles could be easily "cleaned" from the cell surface via mild sugar-treatment and collected by a magnet, avoiding the possible side effects caused by the entrance of particles or their fragments. The delivery and cleaning process is short and effective without compromising the viability and proliferation ability of the cells with delivered molecules, suggesting that the M-PBA particles could be used as promising intracellular delivery agents with a unique combination of efficiency, safety, and flexibility.

11.
Bioelectrochemistry ; 143: 107969, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34637961

RESUMO

Flavonoids, alkaloids, glucosides and tannins with good corrosion inhibition are the main natural components in plants. In this work, procyanidin B2 (PCB2), a natural flavonoid, was firstly isolated from Uncaria laevigata. Corrosion inhibition, chemical reactivity and adsorption of PCB2 on Q235 carbon steel were described by experimental and theoretical studies. The inhibition performance of PCB2 as a green corrosion inhibitor was evaluated by electrochemical and gravimetric tests. The binding active sites and activities thereof on the steel surface were illustrated by quantum chemistry, and the equilibrium configuration was predicted by molecular dynamics simulation. PCB2 exhibits good corrosion inhibition on Q235 steel over a wide temperature range. The electrochemical results show that PCB2 is a mixed inhibitor, and its inhibition efficiency increases with the addition of PCB2 concentration. Moreover, the protective film is formed on the steel and the active corrosion sites are blocked significantly by surface analysis. Additionally, the theoretical calculation proves a strong interaction between PCB2 molecule and carbon steel. Besides, the antimicrobial activity was also preliminarily studied. This suggests that PCB2 exhibits better antimicrobial activity against many Gram-positive and Gram-negative bacteria. As a novel green corrosion inhibitor and antimicrobial agent, PCB2 is worthy of further exploitation.

12.
J Aging Health ; 34(1): 120-129, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34376094

RESUMO

Objectives: Native Hawaiian and other Pacific Islander (NHPI) older adults often experience social disadvantages and poor health outcomes. Physical activity has been associated with better health in other racial groups, but limited studies have examined these associations in NHPI older adults. Methods: Using data from the 2014 Native Hawaiian and Pacific Islander National Health Interview Survey (n = 1,045), logistic regression models examined associations between physical activity and memory/psychological distress/self-rated health. Results: Sufficient levels of physical activity were associated with lower odds of memory problems, serious psychological distress, and poor/fair self-rated health. Unfortunately, only half of the sample reported sufficient physical activity and approximately 30% reported none. Also, 78% of the sample was estimated to be overweight/obese, and 29% had diabetes. Discussion: Culturally-appropriate interventions are recommended to increase physical activity in this population, which could also help reduce high rates of overweight/obesity and diabetes.

13.
Neural Regen Res ; 17(3): 618-624, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34380902

RESUMO

Patients with type 2 diabetes mellitus (T2DM) often have cognitive impairment and structural brain abnormalities. The magnetic resonance imaging (MRI)-based brain atrophy and lesion index can be used to evaluate common brain changes and their correlation with cognitive function, and can therefore also be used to reflect whole-brain structural changes related to T2DM. A total of 136 participants (64 men and 72 women, aged 55-86 years) were recruited for our study between January 2014 and December 2016. All participants underwent MRI and Mini-Mental State Examination assessment (including 42 healthy control, 38 T2DM without cognitive impairment, 26 with cognitive impairment but without T2DM, and 30 T2DM with cognitive impairment participants). The total and sub-category brain atrophy and lesion index scores in patients with T2DM with cognitive impairment were higher than those in healthy controls. Differences in the brain atrophy and lesion index of gray matter lesions and subcortical dilated perivascular spaces were found between non-T2DM patients with cognitive impairment and patients with T2DM and cognitive impairment. After adjusting for age, the brain atrophy and lesion index retained its capacity to identify patients with T2DM with cognitive impairment. These findings suggest that the brain atrophy and lesion index, based on T1-weighted and T2-weighted imaging, is of clinical value for identifying patients with T2DM and cognitive impairment. Gray matter lesions and subcortical dilated perivascular spaces may be potential diagnostic markers of T2DM that is complicated by cognitive impairment. This study was approved by the Medical Ethics Committee of University of South China (approval No. USC20131109003) on November 9, 2013, and was retrospectively registered with the Chinese Clinical Trial Registry (registration No. ChiCTR1900024150) on June 27, 2019.

14.
Food Chem ; 367: 130764, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34384986

RESUMO

The development of food proteins as effective delivery systems is of great significance for the encapsulation of active compounds. Foxtail millet prolamin (FP) has a high level of hydrophobic amino acids and proline, meets the basic characteristics of delivery system, and was described here for the first time as an effective delivery system for the encapsulation of curcumin. The interaction between FP and curcumin was confirmed by fluorescence spectroscopy, showing the joint driving of hydrophobic forces and hydrogen bonds. Curcumin-loaded caseinate-stabilized FP nanodispersions were prepared by anti-solvent/evaporation method. The mean particle size was about 220-235 nm, sharing features of a spherical shape, uniform particle size, and smooth surfaces. High level of curcumin was encapsulated in the FP-based nanoparticles, exhibiting high particle yield (>88.4%) and encouraging encapsulation efficiency (>71.3%). X-ray diffraction and Fourier transform infrared spectroscopy demonstrated that the encapsulated curcumin was amorphous state and interacted with proteins via non-covalent bonds. The nano-sized particles can effectively prevent the degradation of curcumin during heat treatment, and significantly enhance the antioxidant and anti-tumor properties. This study provides a new encapsulant for effective protection and targeted delivery of hydrophobic active biomolecules.


Assuntos
Curcumina , Nanopartículas , Setaria (Planta) , Portadores de Fármacos , Tamanho da Partícula , Prolaminas
15.
Org Lett ; 24(1): 223-227, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-34913708

RESUMO

Rongalite has been used in several challenging synthetic transformations with operationally simple and effective protocols. However, the employment of multiple characteristics of rongalite in synthetic chemistry is comparatively little known. Herein we report a separate-embedding type sulfonylmethylation of sulfoxonium ylides in which rongalite concurrently acted as a sulfone source, C1 synthon, radical initiator, and potential reducing reagent for the first time. Notably, this facile and easy-handling reaction does not require a catalyst or prefunctionalized sulfonylmethylation reagents.

16.
Int J Biol Macromol ; 195: 598-608, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34896471

RESUMO

In this study, two acidic Biluochun Tea polysaccharides (BTP-A11 and BTP-A12) were investigated comparatively, which mainly consisted of Rha, Ara, Gal and GalA, possibly suggesting their pectic nature. Structurally, their galacturonan backbones composed of →4)-α-D-GalpA-(1→ and →2)-α-L-Rhap-(1→ were revealed similar, while Ara- and Gal-based branches attached to the O-2 of →2)-α-L-Rhap-(1→ were in distinctive types, proportions, extensibilities and branching degrees. This could lead to their different macromolecular characteristics, where BTP-A11 with higher Mw presented a more hyper-branched chain conformation and relatively higher structural flexibility/compactness, thereby resulting in a lower exclusion effect and an insufficient hydrodynamic volume. Besides, better radical scavenging activities in vitro were also determined for Gal-enriched BTP-A11, where a larger surface area containing more H-donating groups were related to its higher Mw, more hyper-branched conformation, lower DM and higher DA. Therefore, the understanding of structure-property-activity relationships was improved to some degrees for acidic Biluochun Tea polysaccharides, which could be potentially required for more applications in food, medical and cosmetic fields.

17.
Exp Ther Med ; 23(2): 126, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34970349

RESUMO

Traumatic brain injury (TBI) has been recognized as a serious public health issue and a key contributor to disability and death, with a huge economic burden worldwide. Hydrogen, which is a slight and specific cytotoxic oxygen radical scavenger, has been demonstrated to ameliorate early brain injury (EBI) through reactive oxygen species (ROS), oxidative stress injury, apoptosis and necroptosis. Necroptosis refers to a type of programmed cell death process that has a vital function in neuronal cell death following TBI. The specific function of necroptosis in hydrogen-mediated neuroprotection after TBI, however, has yet to be determined. The present study aimed to examine the neuroprotective effects and possible molecular basis that underly hydrogen-rich saline in TBI-stimulated EBI by examining neural necroptosis in the C57BL/6 mouse model. The brain water content, neurological score, neuroinflammatory cytokines (NF-κΒ, TNF-α, IL-6 and IL-1ß) and ROS were evaluated using flow cytometry. Malondialdehyde, superoxide dismutase (SOD) and glutathione (GSH) levels were evaluated using a biochemical kit. Receptor-interacting protein kinase (RIP)1, RIP3, Nrf2 and Heme oxygenase-1 (HO-1) were evaluated using western blotting. mRNA of Nrf2 and HO-1 were evaluated using quantitative PCR. Neuronal death was evaluated by TUNEL staining. The outcomes illustrated that hydrogen-rich saline treatment considerably enhanced the neurological score, increased neuronal survival, decreased the levels of serum MDA and brain ROS, increased the levels of serum GSH and SOD. In addition the protein expression levels of RIP1 and RIP3 and the cytokines NF-κB, TNF-α, IL-1ß and IL-6 were downregulated compared with the TBI group, which demonstrated that hydrogen-rich saline-induced inhibition of necroptosis and neuroinflammation ameliorated neuronal death following TBI. The neuroprotective capacity of hydrogen-rich saline was demonstrated to be partly dependent on the ROS/heme oxygenase-1 signaling pathway. Taken together, the findings of the present study indicated that hydrogen-rich saline enhanced neurological outcomes in mice and minimized neuronal death by inducing protective effects against neural necroptosis as well as neuroinflammation.

18.
FASEB J ; 36(1): e22106, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34918375

RESUMO

Choroidal neovascularization (CNV), a leading cause of blindness in the elderly, is routinely treated with vascular endothelial growth factor (VEGF) inhibitors that have limited efficacy and potentially adverse side effects. An unmet clinical need is to develop novel therapies against other angiogenic factors for alternative or combination treatment to improve efficacy and safety. We recently described secretogranin III (Scg3) as a disease-selective angiogenic factor, causally linked to diabetic retinopathy and acting independently of the VEGF pathway. An important question is whether such a disease-selective Scg3 pathway contributes to other states of pathological angiogenesis beyond diabetic retinopathy. By applying a novel in vivo endothelial ligand binding assay, we found that the binding of Scg3 to CNV vessels in live mice was markedly increased over background binding to healthy choriocapillaris and blocked by an Scg3-neutralizing antibody, whereas VEGF showed no such differential binding. Intravitreal injection of anti-Scg3 humanized antibody Fab (hFab) inhibited Matrigel-induced CNV with similar efficacy to the anti-VEGF drug aflibercept. Importantly, a combination of anti-Scg3 hFab and aflibercept synergistically alleviated CNV. Homozygous deletion of the Scg3 gene markedly reduced CNV severity and abolished the therapeutic activity of anti-Scg3 hFab, but not aflibercept, suggesting a role for Scg3 in VEGF-independent CNV pathogenesis and therapy. Our work demonstrates the stringent disease selectivity of Scg3 binding and positions anti-Scg3 hFab as a next-generation disease-targeted anti-angiogenic therapy for CNV.


Assuntos
Neovascularização de Coroide/metabolismo , Cromograninas/metabolismo , Transdução de Sinais , Animais , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/genética , Cromograninas/genética , Feminino , Fragmentos Fab das Imunoglobulinas/farmacologia , Masculino , Camundongos , Camundongos Knockout , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Plant Dis ; 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34854764

RESUMO

Phoebe sheareri (Hemsl.) Gamble is a high-value timber tree species with a wide range of uses. It can also be applied for landscape afforestation considering its beautiful shape and luxuriant branches. Previous studies disclosed that Neofusicum parvum can cause ulceration and necrosis on the main stems of P. sheareri (Chen et al. 2019), and branch wilt of P. zhennan (Zhu et al. 2019). In September 2019, anthracnose was observed from P. sheareri leaves in Lishui, Zhejiang province, China. The diseased leaves are characterized by dark brown lesions. The infection usually starts from the leaf tip or edge, then the infected leaves turn yellow, wither and fall finally. The infection sometimes occurrs on the small twigs, causing the whole branch to wither. Plants from 15 plantations were surveyed, and the disease incidence was about 30%. A total number of 15 freshly infected leaves were collected and cut into small pieces (5×5 mm), sterilized in 75% ethanol solution for 30 s, and washed with sterile water three times. They were further sanitized in 2% sodium hypochlorite solution for 2 to 3 minutes and dried in sterile filter paper after being washed with sterile water another three times. Leaf pieces were transferred to potato dextrose agar (PDA) plates and incubated at 25℃ in the dark for 3 days. The fungal cultures were purified and the typical isolate (TJ01) was selected for further morphological characterization and DNA sequence comparison. The strain was initially grayish white, villous, and posteriorly grayish green, and produced orange red spore clumps. The spores are single celled after maturation, oblong, colorless, and the size ranges from 8.5-19.5 × 4.5-5.5 µm. Morphological characteristics of the obtained isolate are consistent with those in the genus of Colletotrichum. DNA of the isolate was extracted and sequence data obtained and compared with those downloaded from GenBank. The internal transcribed spacer (ITS), intronic glyceraldehyde-3-phosphate dehydrogenase (GAPDH), actin (ACT), beta-tubulin (TUB2), and calmodulin (CAL) genes were partially amplified and sequenced using the primer pairs ITS-1 + ITS-4, GDF + GDR, ACT-512F + ACT-783R, T1 + Bt2b, CL1C + Cl2C, respectively (Fu et al. 2019). The resulted nucleotide sequences were individually subjected to BLAST searche in GenBank. The nucleotide sequences of ITS (MZ088144), GAPDH (MZ133607), ACT (MZ133608), TUB2 (MZ133609), CAL (MZ133610) of the isolate showed 99.83% similarity to ITS sequence (MN829453), 98.24% similarity to GAPDH sequence (MN525875), 98.94% similarity to ACT sequence (MK341539), 100% similarity to TUB2 sequence (MG657352), and 100% similarity to CAL sequence (MN525839). The phylogenetic tree was constructed using MEGA 7 based on the tandem of five genes (ITS-GAPDH-ACT-TUB2-CAL). The result revealed that the isolate resides in the clade of C. fructicola species. Inoculation was done on leaves of ten P. sheareri plants in the field to verify its pathogenicity. Three healthy leaves of each plant were surface sterilized with 75% ethanol and dried up. The leaves were punctured using a sterilized needle, inoculated with 5-mm-diameter PDA plugs excised from 7-day-old cultures, and wrapped with parafilm. Nine pieces of healthy leaves inoculated with sterilized PDA plugs were served as controls. Disease symptoms developed on all the C. fructicola-inoculated leaves 5 days after inoculation, and a yellow brown lesion became apparent 16 days later, whereas the control leaves remained asymptomatic. C. fructicola was reisolated from the lesions, but not from the control leaves, fulfilling the Koch's postulates. This fungus is a well-known pathogen and has led to anthracnose on many plant species globally. However, our study represents the first report of C. fructicola causing anthracnose on P. sheareri worldwide and its potential threat should be evaluated.

20.
Nanomicro Lett ; 14(1): 23, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34888757

RESUMO

In conventional ethylene carbonate (EC)/propylene carbonate (PC) electrolyte, sodium metal reacts spontaneously and deleteriously with solvent molecules. This significantly limits the practical feasibility of high-voltage sodium metal batteries based on Na metal chemistry. Herein, we present a sodium metal alloy strategy via introducing NaIn and Na2In phases in a Na/In/C composite, aiming at boosting Na ion deposition stability in the common EC/PC electrolyte. Symmetric cells with Na/In/C electrodes achieve an impressive long-term cycling capability at 1 mA cm-2 (> 870 h) and 5 mA cm-2 (> 560 h), respectively, with a capacity of 1 mAh cm-2. In situ optical microscopy clearly unravels a stable Na ion dynamic deposition process on the Na/In/C composite electrode surface, attributing to a dendrite-free and smooth morphology. Furthermore, theoretical simulations reveal intrinsic mechanism for the reversible Na ion deposition behavior with the composite Na/In/C electrode. Upon pairing with a high-voltage NaVPOF cathode, Na/In/C anode illustrates a better suitability in SMBs. This work promises an alternative alloying strategy for enhancing Na metal interfacial stability in the common EC/PC electrolyte for their future applications.

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