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1.
Appl Opt ; 60(22): 6366-6370, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34612870

RESUMO

We propose an ultra-broadband terahertz bandpass filter with dynamically tunable attenuation based on a graphene-metal hybrid metasurface. The metasurface unit cell is composed of two metal stripes enclosed with a graphene rectangular ring. Results show that when the metasurface is normally illuminated by a terahertz wave polarized along the metal stripes, it can act as an ultra-broadband bandpass filter over the spectral range from 1.49 THz to 4.05 THz, corresponding to a fractional bandwidth of 92%. Remarkably, high transmittance above 90% covering the range from 1.98 THz to 3.95 THz can be achieved. By changing the Fermi level of graphene, we find that the attenuation within the passband can be dynamically tuned from 2% to 66%. We expect that the proposed ultra-broadband terahertz bandpass filter with tunable attenuation will find applications in terahertz communication and detection and sensing systems.

2.
Clin Lab ; 67(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34542973

RESUMO

BACKGROUND: Myeloproliferative neoplasms (MPN) are hematopoietic disorders characterized by abnormal proliferation of the myeloid lineage. Three classic subtypes are polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). These disorders are well known for their association with the JAK2 V617F mutation, in addition to mutations in MPL exon 10, and JAK2 exon 12. CALR mutations were detected in approximately 20% to 25% of patients with ET and PMF and not in patients with PV. Most CALR mutations were deletions and insertions in exon 9, which caused frameshift mutations. METHODS: This study included 60 Taiwanese patients with MPN. We identified CALR mutations in patients with MPN using the high-resolution melting (HRM) analysis. Additionally, the HRM analysis was compared with ipsogen CALR RGQ PCR. To confirm the results of HRM and ipsogen CALR RGQ PCR, sequencing analysis was also conducted all the samples. RESULTS: Up to 6.25% of CALR mutations were successfully detected in patients with MPN using HRM analysis. Eight out of 65 patients (12.3%) were positive for the presence of CALR mutation, including p.L367fs*46 and p.K385fs*47. The results proved 100% comparable to those obtained using ipsogen CALR RGQ PCR. CONCLUSIONS: The HRM analysis and ipsogen CALR RGQ PCR are feasible and reliable techniques for the detection of CALR mutation. Furthermore, HRM offers several benefits, for example, it is time-saving, inexpensive, and does not require many personnel.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Calreticulina/genética , Humanos , Janus Quinase 2/genética , Mutação , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/genética , Receptores de Trombopoetina/genética
3.
Am J Chin Med ; : 1-46, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34559620

RESUMO

Schisandra sphenanthera Rehd. et Wils (S. sphenanthera) is a single species of Schisandra genus, Magnoliaceae family, and it is a famous medicinal herb mostly growing in southern China, China Taiwan and Vietnam. S. sphenanthera is usually used for the treatments of hepatitis, Alzheimer's disease, renal transplantation, osteoporosis, and insomnia. In present studies, approximately 310 natural constituents have been isolated from S. sphenanthera, including lignans, triterpenes, volatile oils, and polysaccharides, which were mainly obtained from the fruits and stems of S. sphenanthera. Pharmocological studies have shown that the extracts and monomeric compounds of S. sphenanthera possessed wide-range bioactivities, such as antitumor, anti-oxidant, anti-inflammatory, osteoblastic, immune regulation, neuroprotective, kidney protection, hepatoprotective, and antiviral activities. However, resource availability, quality control measures, in-depth in vivo pharmacological study, and clinical application are still insufficient and deserve further studies. This review systematically summarized literatures on the botany, phytochemistry, pharmacology, development utilization, and clinical application of S. sphenanthera, in hopes of provide a useful reference for researchers for further studies of this plant.

4.
Biosens Bioelectron ; 194: 113602, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34481241

RESUMO

Inhibition of HIV-1 protease (PR) activity is realized by exposure to 60Co γ-radiation. The radiation effects on enzyme kinetics of HIV-1 PR are subsequently monitored using nanopore sensor. Substantial loss of proteolytic efficiency towards GagPol polypeptide is observed due to the radiation treatment. Results shows ~50% of GagPol polypeptide was not involved in HIV-1 PR proteolysis by exposure to ultra-low intensity of γ-radiation (0.1K Gy), and the values reach to over 90% with high γ-ray treatment. Besides, the inactivation effect is also verified in blood samples which contain the virus protease. Our finding provides the potential benefits of γ-radiation to inactivate viral proteinic function, and might be a complementary to the designation of HIV-1 PR inhibitors.


Assuntos
Técnicas Biossensoriais , HIV-1 , Nanoporos , Protease de HIV , Proteólise
5.
ACS Sens ; 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34528798

RESUMO

HIV-1 Tat protein, an intercellular transporter with a determinant function of delivering "information-rich" molecules in viral multiplication, was tryptic-hydrolyzed and real-time single molecule-monitored in a transmembrane pore. The electrokinetic studies revealed the catalytic and inhibitory effects on enzymatic digestion associated with Ca2+ and Cu2+ ions, respectively, in response to binding interactions with trypsin. Our strategy permits accurate and distinguishable sensing of Ca2+ and Cu2+ via an enzyme assay. In addition, considering the closer mimic of the real situation of HIV spread, measurements in the serum and on cells were also investigated. Transmembrane current measurements together with fluorescence microscopy imaging indicated the potential to perturb the Tat transport in the serum environment and on cells. Because the involved Tat proteolysis should prevent the occurrence of viral delivery, the presented method probably enables efficient hindrance to HIV-1 infection, in complementary to current traditional treatments.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34394384

RESUMO

Morels (Morchella spp.) are a genus of edible fungi with important economic and medicinal value. In this study, a novel peptide (MIPP) was extracted from the fruiting bodies of Morchella importuna using gel filtration chromatography. Structural analysis showed that the molecular mass of MIPP is 831 Da, and it has a simple amino acid sequence: Ser-Leu-Ser-Leu-Ser-Val-Ala-Arg. To explore the antitumor activity of MIPP, the effect of MIPP on HeLa cell apoptosis and the underlying preventative mechanisms were investigated. Results showed that MIPP reduced the viability of HeLa cells in a concentration-dependent manner. TUNEL analysis and flow cytometric examination showed that MIPP decreased cell proliferation via a mitochondrial-dependent pathway, as manifested by downregulation of Bcl-2/Bax, promotion of the movement of cytochrome C from the mitochondria to the cytoplasm, and triggering of caspase-9 and caspase-3. Therefore, MIPP may be a promising tumor-preventive agent, especially in human cervical cancer.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34360492

RESUMO

Outdoor physical activity duration is a key component of outdoor physical activity behavior of older adults, and therefore, an important determinant of their total physical activity levels. In order to develop a successful outdoor physical activity program, it is important to identify any heterogeneity in preferences for outdoor physical activity duration patterns among older adults. In addition, more insight is needed in the influence of environmental characteristics on duration choice for creating supportive neighborhood environments matching individuals' preferences. To this end, a mixed multinomial logit model is estimated based on one-week data collected among 336 respondents aged 60 or over in 2017 in Dalian, China. The present model formulation accounts for heterogeneity in individuals' preferences and allows for the analysis of substitution and complementary relationships between the different patterns of outdoor physical activity duration. Results indicate that older adults vary significantly in their preferences for each outdoor physical activity duration pattern. Moreover, short walking duration, short exercise duration and medium exercise duration are substitutes for medium walking duration while short walking duration and short exercise duration are complements for medium exercise duration in terms of individuals' outdoor physical activity duration preferences. In addition, we find that distance to the nearest park, footpath conditions and neighborhood aesthetics are associated with older adults' outdoor physical activity duration choice.


Assuntos
Planejamento Ambiental , Caminhada , Idoso , Exercício Físico , Humanos , Modelos Logísticos , Características de Residência
8.
Genes (Basel) ; 12(8)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34440295

RESUMO

Chinese kale (Brassica oleracea var. alboglabra) is rich in carotenoids, and neoxanthin is one of the most important carotenoids in Chinese kale. In this study, the function of the neoxanthin synthase gene (BoaNXS) in Chinese kale was investigated. BoaNXS, which had a 699-bp coding sequence, was cloned from the white flower cultivar of Chinese kale and was expressed in all developmental stages and organs of Chinese kale; its expression was highest in young seeds. The subcellular localization indicated that BoaNXS was localized in the chloroplast. BoaNXS-overexpressed plants were obtained via Agrobacterium-mediated transient overexpression methodology, and the gene overexpression efficiencies ranged from 2.10- to 4.24-fold. The color in the leaves of BoaNXS-overexpressed plants changed from green to yellow-green; the content of total and individual carotenoids, such as neoxanthin, violaxanthin, and lutein, was significantly increased, and the expression levels of most carotenoid biosynthetic genes were notably increased. These findings indicated that BoaNXS is of vital importance in carotenoid biosynthesis in Chinese kale and could be used as a candidate gene for enriching the carotenoid accumulation and color of Chinese kale and other Brassica vegetables.

9.
Front Microbiol ; 12: 646567, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122362

RESUMO

In this study, the mitogenome of Hannaella oryzae was sequenced by next-generation sequencing (NGS) and successfully assembled. The H. oryzae mitogenome comprised circular DNA molecules with a total size of 26,444 bp. We found that the mitogenome of H. oryzae partially deleted the tRNA gene transferring cysteine. Comparative mitogenomic analyses showed that intronic regions were the main factors contributing to the size variations of mitogenomes in Tremellales. Introns of the cox1 gene in Tremellales species were found to have undergone intron loss/gain events, and introns of the H. oryzae cox1 gene may have different origins. Gene arrangement analysis revealed that H. oryzae contained a unique gene order different from other Tremellales species. Phylogenetic analysis based on a combined mitochondrial gene set resulted in identical and well-supported topologies, wherein H. oryzae was closely related to Tremella fuciformis. This study represents the first report of mitogenome for the Hannaella genus, which will allow further study of the population genetics, taxonomy, and evolutionary biology of this important phylloplane yeast and other related species.

10.
Ann Plast Surg ; 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34139739

RESUMO

BACKGROUND: The advantages of good biocompatibility, low degradation and low antigenicity of collagen, and the osteogenic differentiation characteristics of bone mesenchymal stem cells (BMSCs) were used to promote the recovery of bone defects using partially deproteinized bone (PDPB) by bone tissue engineering (BTE). METHODS: The BMSCs were identified by examining their potential for osteogenic, lipogenic, and chondrogenic differentiation. The prepared pure PDPB was ground into bone blocks 4 × 2 × 2 mm in size, which were divided into the following groups: PDPB group, PDPB + collagen group, PDPB + collagen + BMSC group, PDPB with a composite collagen nanofilm, and BMSCs injected into the tail vein. At 2, 4, 6, and 8 weeks after surgery, the effects of the implants in the different groups on bone defect repair were continuously and dynamically observed through x-ray examination, gross specimen observation, histological evaluation, and microvascularization detection. RESULTS: Postoperative x-ray examination and gross specimen observation revealed that, after 4 to 8 weeks, the external contour of the graft was gradually weakened, and the transverse comparison showed that the absorption of the graft and fusion of the defect were more obvious in PDPB + collagen + BMSC group than in PDPB group and PDPB + collagen group, and the healing was better (P < 0.05). Hematoxylin and eosin staining of histological sections showed very active proliferation of trabecular hematopoietic cells in groups PDPB + collagen + BMSC and PDPB + collagen. Masson's trichrome staining for evaluation of bone defect repair showed that the mean percent area of collagen fibers was greater in PDPB + collagen + BMSC group than in the PDPB group, with degradation of the scaffold material and the completion of repair. Immunofluorescence staining showed significantly enhanced expression of the vascular marker CD31 in group C (P < 0.05). CONCLUSIONS: The proposed hybrid structure of the collagen matrix and PDPB provides an ideal 3-dimensional microenvironment for patient-specific BTE and cell therapy applications. The results showed that collagen appeared to regulate MSC-mediated osteogenesis and increase the migration and invasion of BMSCs. The combination of collagen nanofilm and biological bone transplantation with BMSC transplantation enhanced the proliferation and potential of the BMSCs for bone regeneration, successfully promoting bone repair after implantation at the defect site. This method may provide a new idea for treating clinical bone defects through BTE.

11.
Front Cell Dev Biol ; 9: 641271, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33748130

RESUMO

B-cell acute lymphocytic leukemia (B-ALL), a common blood cancer in children, leads to high mortality. Cyclin-dependent kinase 9 inhibitor (CDK9i) effectively attenuates acute myeloid leukemia and chronic lymphoblastic leukemia by inducing apoptosis and inhibiting cell proliferation. However, the effect of CDK9i on B-ALL cells and the underlying mechanisms remain unclear. In this study, we showed that CDK9i induced the apoptosis of B-ALL cells in vitro by activating the apoptotic pathways. In addition, CDK9i restrained the glycolytic metabolism of B-ALL cells, and CDK9i-induced apoptosis was enhanced by co-treatment with glycolysis inhibitors. Furthermore, CDK9i restained the glycolysis of B-ALL cell lines by markedly downregulating the expression of glucose transporter type 1 (GLUT1) and the key rate-limiting enzymes of glycolysis, such as hexokinase 2 (HK2) and lactate dehydrogenase A (LDHA). Moreover, cell apoptosis was rescued in B-ALL cells with over-expressed c-Myc after treatment with CDK9i, which is involved in the enhancement of glycolytic metabolism. In summary, our findings suggest that CDK9 inhibitors induce the apoptosis of B-ALL cells by inhibiting c-Myc-mediated glycolytic metabolism, thus providing a new strategy for the treatment of B-ALL.

12.
Front Genet ; 12: 534871, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33659021

RESUMO

The genus of Tricholoma is a group of important ectomycorrhizal fungi. The overlapping of morphological characteristics often leads to the confusion of Tricholoma species classification. In this study, the mitogenomes of five Tricholoma species were sequenced based on the next-generation sequencing technology, including T. matsutake SCYJ1, T. bakamatsutake, T. terreum, T. flavovirens, and T. saponaceum. These five mitogenomes were all composed of circular DNA molecules, with sizes ranging from 49,480 to 103,090 bp. Intergenic sequences were considered to be the main factor contributing to size variations of Tricholoma mitogenomes. Comparative mitogenomic analysis showed that the introns of the Agaricales mitogenome experienced frequent loss/gain events. In addition, potential gene transfer was detected between the mitochondrial and nuclear genomes of the five species of Tricholoma. Evolutionary analysis showed that the rps3 gene of the Tricholoma species was under positive selection or relaxed selection in the evolutionary process. In addition, large-scale gene rearrangements were detected between some Tricholoma species. Phylogenetic analysis using the Bayesian inference and maximum likelihood methods based on a combined mitochondrial gene set yielded identical and well-supported tree topologies. This study promoted the understanding of the genetics, evolution, and phylogeny of the Tricholoma genus and related species.

13.
Int J Biol Macromol ; 172: 560-572, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33476615

RESUMO

In the present study, eleven novel complete mitogenomes of Boletus were assembled and compared. The eleven complete mitogenomes were all composed of circular DNA molecules, with sizes ranging from 32,883 bp to 48,298 bp. The mitochondrial gene arrangement of Boletus varied greatly from other Boletales mitogenomes, and gene position reversal were observed frequently in the evolution of Boletus. Across the 15 core protein-coding genes (PCGs) tested, atp9 had the least and rps3 had the largest genetic distances among the eleven Boletus species, indicating varied evolution rates of core PCGs. In addition, the Ka/Ks value for nad3 gene was >1, suggesting that this gene was subject to possible positive selection pressure. Comparative mitogenomic analysis indicated that the intronic region was significantly correlated with the size of mitogenomes in Boletales. Two large-scale intron loss events were detected in the evolution of Boletus. Phylogenetic analyses based on a combined mitochondrial gene dataset yielded a well-supported (BPP ≥ 0.99; BS =100) phylogenetic tree for 72 Agaricomycetes, and the Boletus species had a close relationship with Paxillus. This study served as the first report on complete mitogenomes in Boletus, which will further promote investigations of the genetics, evolution and phylogeny of the Boletus genus.


Assuntos
Basidiomycota/genética , Proteínas Fúngicas/genética , Genoma Mitocondrial , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Micorrizas/genética , Sequência de Aminoácidos , Basidiomycota/classificação , Basidiomycota/metabolismo , Evolução Biológica , Éxons , Florestas , Proteínas Fúngicas/classificação , Proteínas Fúngicas/metabolismo , Tamanho do Genoma , Íntrons , Mitocôndrias/metabolismo , Proteínas Mitocondriais/classificação , Proteínas Mitocondriais/metabolismo , Micorrizas/classificação , Micorrizas/metabolismo , Filogenia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Árvores/microbiologia
14.
Environ Sci Pollut Res Int ; 28(21): 27025-27032, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33501579

RESUMO

Endothelial cell is one critical structure of blood vessels, and irregular migration and proliferation of endothelial cell might cause progression of several vascular diseases such as atherosclerosis and restenosis. We showed that TNF-α, PDGF-bb, and IL-1ß promote RNCR3 expression in a dose-dependent manner inhuman endothelial cell. RNCR3 level is higher in serum of atherosclerosis patients compared with those in control volunteers. Overexpression of RNCR3 promotes cell proliferation and three inflammatory cytokine secretion including IL-6, IL-1ß, and TNF-α in endothelial cell. We illustrated that overexpression of RNCR3 inhibits miR-185-5p expression in endothelial cell. Furthermore, we indicated that miR-185-5p level is lower in the serum of patients with atherosclerosis compared with those in control volunteers. There is a negative correlation between miR-185-5p and RNCR3 expression in serum of patients with atherosclerosis. Using Targetscan, it predicted that miR-185-5p may bind to cyclin D2 and miR-185-5p is one potential target of miR-185-5p. Luciferase reporter data indicated that miR-185-5p suppresses luciferase value of wild-type cyclin D2 while it has no influence of cyclin D2 mutant. Overexpression of RNCR3 enhances cyclin D2 expression in endothelial cell. Moreover, RNCR3 induces cell growth and enhances inflammatory cytokine secretion through modulating cyclin D2 expression in endothelial cell. These results suggested that RNCR3 may serve as one new target for the treatment of atherosclerosis.


Assuntos
Aterosclerose , Células Endoteliais/citologia , MicroRNAs , RNA Longo não Codificante , Aterosclerose/genética , Proliferação de Células , Ciclina D2 , Citocinas , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética
15.
Comput Struct Biotechnol J ; 19: 401-414, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33489009

RESUMO

The order Boletales is a group of fungi with complex life styles, which include saprophytic and ectomycorrhizal mushroom-forming fungi. In the present study, the complete mitogenomes of two saprophytic Boletales species, Coniophora olivacea, and C. puteana, were assembled and compared with mitogenomes of ectomycorrhizal Boletales. Both mitogenomes comprised circular DNA molecules with sizes of 78,350 bp and 79,655 bp, respectively. Comparative mitogenomic analysis indicated that the two saprophytic Boletales species contained more plasmid-derived (7 on average) and unknown functional genes (12 on average) than the four ectomycorrhizal Boletales species previously reported. In addition, the core protein coding genes, nad2 and rps3, were found to be subjected to positive selection pressure between some Boletales species. Frequent intron gain/loss events were detected in Boletales and Basidiomycetes, and several novel intron classes were found in two Coniophora species. A total of 33 introns were detected in C. olivacea, and most were found to have undergone contraction in the C. olivacea mitogenome. Mitochondrial genes of Coniophora species were found to have undergone large-scale gene rearrangements, and the accumulation of intra-genomic repeats in the mitogenome was considered as one of the main contributing factors. Based on combined mitochondrial gene sets, we obtained a well-supported phylogenetic tree for 76 Basidiomycetes, demonstrating the utility of mitochondrial gene analysis for inferring Basidiomycetes phylogeny. The study served as the first report on the mitogenomes of the family Coniophorineae, which will help to understand the origin and evolution patterns of Boletales species with complex lifestyles.

16.
Gynecol Endocrinol ; 37(2): 121-125, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32812809

RESUMO

Polycystic ovary syndrome (PCOS) is a common reproductive and endocrine disease. However, there have not been any bibliometric studies on the latest scientific results and research trends of PCOS. This study aimed to review the state of research in PCOS worldwide. Publications on PCOS from 2009 to 2019 were identified and evaluated from the database Web of Science. A total of 7814 articles were retrieved. Shanghai Jiao Tong University published the most articles, with 218 publications. Gynecol Endocrinol had the greatest number of publications (n = 541). J Clin Endocr Metab was cited the most, with a total of 32,207 times. An article written by March et al. in 2010 had the most global citations (737 times) and local citations (463 times). From 2009 to 2019, the number of PCOS global publications gradually increased. Gynecol Endocrinol and Endocr Metab were popular journals for PCOS research. Research trends gradually shifted from treatment and methodology to genetics and basic research. The terms 'microrna,' 'rt qpcr,' 'lncrna,' and 'histological examination' may be hotspots that should be focused on in PCOS research.

17.
Nat Prod Res ; 35(1): 108-115, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31137985

RESUMO

Three new steroidal saponins (1-3), together with four known compounds (4-7), were isolated from the roots and rhizomes of Rohdea chinensis Baker, and their structures were determined as (24S, 25 R)-1ß-hydroxy-3ß-[(ß-D-glucopyranoside)oxy]-spirost-5-en-24-yl-ß-D-glucopyranoside (1) and (24S)-spirost-25(27)-en-1ß, 3ß, 4ß, 5ß, 6ß, 24ß-hexahydroxy-24-O-ß-D-glucopyranoside (2), (22S, 25S)-1ß, 3ß, 4ß, 5ß, 26, 27-hexanol-furospirost-5, 26-O-ß-D-glucopyranoside (3), together with four known compounds 3-epi-diosgenin-3-ß-D-glucopyranosid (4), 3-epiruscogenin (5), 25(R)-1ß-hydroxy-spirost-5-en-3α-yl-O-ß-D-glucopyranoside (6) and tupichinin A (7), on the basis of physico-chemical properties and spectral analysis. In this study, compounds 1-3 and 5-7 were evaluated for their cytotoxic activity against SW620, A549 and HepG2 tumor cell lines. Among them, compound 7 showed moderate cytotoxicity against two human cancer cell lines A549 and HepG 2 with IC50 values of 25.3 ± 2.6 and 26.1 ± 2.5 µM, respectively.


Assuntos
Asparagaceae/química , Saponinas/química , Saponinas/farmacologia , Células A549 , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Rizoma/química , Esteroides/química
18.
Nat Prod Res ; 35(7): 1159-1166, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31322441

RESUMO

A new coprostanol glycoside, 26-trihydroxy-16, 22-dioxo-3ß-[(α-L-rhamnopyranosyl)oxy]-5ß-cholestan-1ß-yl O-α-L-rhamnopyranosyl-(1→2)-ß-D-fucopyranoside (1) (25S)-5ß-spirostan-1ß,2ß,3ß, 4ß,5ß, 6ß-hexol (2), a new C-22 steroidal lactone saponin, (20 R)-16ß-trihydroxy-3ß-[(α-L-rhamnopyranosyl)oxy]-1ß-[(O-α-L-rhamnopyranosyl-(1→2)-ß-D-xylopyranosyl)oxy]-5ß-pregnane-20-oic acid γ-lactone (3) along with two known pregnane glycosides (4 and 5) were obtained from the roots of Reineckia carnea. Their structures were determined by 1 D, 2 D NMR, IR and MS data analysis. In addition, the cytotoxic activities in HT-29, HCT116, H1299 and A549 tumor cells of the isolated compounds (1 - 5) were determined by the MTT method. The results showed that only compound 1 exhibited weak effect against these cells with IC50 values ranging from 63.36 µM to 105.01 µM.


Assuntos
Asparagaceae/química , Raízes de Plantas/química , Esteroides/isolamento & purificação , Antineoplásicos/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Hidrólise , Concentração Inibidora 50 , Espectroscopia de Prótons por Ressonância Magnética , Esteroides/química , Esteroides/farmacologia , Açúcares/análise
19.
Bioorg Chem ; 106: 104512, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33293056

RESUMO

This study aimed to obtain tyrosinase inhibitors for treating hyperpigmentation. A series of cinnamyl ester analogues were designed and synthesized with cinnamic acid (CA) and peaonol compounds. The safety, melanin content and inhibitory effects of all target compounds were evaluated. In the enzymatic activity test, the inhibitory rate of compounds 8, 13 and 14 had stronger inhibitory activity with the IC50 values of 20.7 µM, 13.98 µM and 15.16 µM, respectively than the positive drug kojic acid (IC50 with 30.83 µM). The cytotoxicity evaluation showed that compounds 13 and 14 have higher safety than the other compounds to the proliferation of B16F10 cells. The result of the melanocyte test supported that compound13 has stronger cellular tyrosinase inhibitory activity than kojic acid and arbutin at 100 µM and 200 µM. The enzyme kinetics mechanism revealed that compound 13 was a non-competitive inhibitor while compounds 8 and 14 were mixed inhibitors. For the experiments of melanin content and tyrosinase activity in the B16F10 melanona cells, the inhibition rates of compounds 8, 14 and 13 were with 19.62%, 20.59% and 23.83%, respectively. In addition, compound 13 revealed the highest inhibitory activity to tyrosinase in the melanocyte with inhibition rates of 23.83%, which was better than kojic acid and arbutin (19.21% and 20.45%) at the same concentration. In the anti-melanogenesis experiment, compounds 8 and 13 had better anti-melanin effects than kojic acid from 25 µM to 100 µM. In summary, the results indicated that compounds 8, 13 and 14 had better tyrosinase inhibitory activity and anti-melanogenesis activity. Especially, the compound 13 has potentiality to develop novel tyrosinase inhibitors and whitening agents. The docking studies results revealed that the functional group of compound 13 mostly depends on the phenolic hydroxyl moiety, and its hydroxyl group did not insert into the active site of tyrosinase, which was in agreement with the results of the kinetics study.

20.
Sci Total Environ ; 754: 141925, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32898780

RESUMO

Nitrogen-doped carbon intercalated molybdenum disulfide nanohybrid (NC-MoS2) with well-interconnected nanosheets was successfully fabricated using a one-pot hydrothermal method and applied as a novel adsorbent to remove tetracycline (TC) from aqueous solutions. Series material characterizations indicated that the intercalation of nitrogen-doped carbon into MoS2 nanosheets could produce widened interlayer spacing, enlarge the specific surface area and create more extensive functional groups. The adsorption kinetics and isotherms investigations revealed that the pseudo-second-order model and Langmuir isotherm model could fit well the TC adsorption behavior of NC-MoS2. Particularly, NC-MoS2 possessed a high maximum adsorption capacity (1128.4 mg/g) that was approximately 2.8 times that of pristine MoS2 (409.84 mg/g) at 308 K and pH = 6.0 ± 0.1. Furthermore, the relevant thermodynamic parameters indicated that the adsorption process was spontaneous and endothermic. The adsorption process was dependent on multiple interactions including hydrophobicity, π-π stacking interaction and hydrogen bond. These findings demonstrated that NC-MoS2 had potential applications for treating TC-containing water and broadened the application of metal sulfides in the environmental field.


Assuntos
Molibdênio , Poluentes Químicos da Água , Adsorção , Carbono , Dissulfetos , Concentração de Íons de Hidrogênio , Cinética , Soluções , Tetraciclina , Poluentes Químicos da Água/análise
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