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1.
Cell ; 141(1): 117-28, 2010 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-20371349

RESUMO

The association of p120 catenin (p120) with the juxtamembrane domain (JMD) of the cadherin cytoplasmic tail is critical for the surface stability of cadherin-catenin cell-cell adhesion complexes. Here, we present the crystal structure of p120 isoform 4A in complex with the JMD core region (JMD(core)) of E-cadherin. The p120 armadillo repeat domain contains modular binding pockets that are complementary to electrostatic and hydrophobic properties of the JMD(core). Single-residue mutations within the JMD(core)-binding site of p120 abolished its interaction with E- and N-cadherins in vitro and in cultured cells. These mutations of p120 enabled us to clearly differentiate between N-cadherin-dependent and -independent steps of neuronal dendritic spine morphogenesis crucial for synapse development. NMR studies revealed that p120 regulates the stability of cadherin-mediated cell-cell adhesion by associating with the majority of the JMD, including residues implicated in clathrin-mediated endocytosis and Hakai-dependent ubiquitination of E-cadherin, through its discrete "dynamic" and "static" binding sites.


Assuntos
Caderinas/química , Caderinas/metabolismo , Cateninas/química , Cateninas/metabolismo , Adesão Celular , Animais , Caderinas/genética , Cateninas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Camundongos , Modelos Moleculares , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , delta Catenina
2.
Cereb Cortex ; 33(8): 4293-4304, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36030380

RESUMO

Neocortical vasoactive intestinal polypeptide-expressing (VIP+) interneurons display highly diverse morpho-electrophysiological and molecular properties. To begin to understand the function of VIP+ interneurons in cortical circuits, they must be clearly and comprehensively classified into distinct subpopulations based on specific molecular markers. Here, we utilized patch-clamp RT-PCR (Patch-PCR) to simultaneously obtain the morpho-electric properties and mRNA profiles of 155 VIP+ interneurons in layers 2 and 3 (L2/3) of the mouse somatosensory cortex. Using an unsupervised clustering method, we identified 3 electrophysiological types (E-types) and 2 morphological types (M-types) of VIP+ interneurons. Joint clustering based on the combined electrophysiological and morphological features resulted in 3 morpho-electric types (ME-types). More importantly, we found these 3 ME-types expressed distinct marker genes: ~94% of Sncg+ cells were ME-type 1, 100% of Mybpc1+ cells were ME-type 2, and ~78% of Parm1+ were ME-type 3. By clarifying the properties of subpopulations of cortical L2/3 VIP+ interneurons, this study establishes a basis for future investigations aiming to elucidate their physiological roles.


Assuntos
Córtex Somatossensorial , Peptídeo Intestinal Vasoativo , Animais , Camundongos , Fenômenos Eletrofisiológicos , Interneurônios/fisiologia , Córtex Somatossensorial/fisiologia , Peptídeo Intestinal Vasoativo/metabolismo , Proteínas de Neoplasias/metabolismo , gama-Sinucleína/metabolismo , Proteína de Ligação a Androgênios/metabolismo
3.
Nano Lett ; 23(11): 5164-5170, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37263581

RESUMO

Topological defects are fundamental concepts in physics, but little is known about the transition between distinct types across different dimensionalities. In topological magnetism, as in field theory, the transition between 1D strings and 0D monopoles is a key process whose observation has remained elusive. Here, we introduce a novel mechanism that allows for the controlled stabilization of emergent monopoles and show that magnetic skyrmion strings can be folded into monopoles. Conversely, they act as seeds out of which the entire string structure can unfold, containing its complete information. In chiral magnets, this process can be observed by resonant elastic X-ray scattering when the objects are in proximity to a polarized ferromagnet, whereby a pure monopole lattice is emerging on the surface. Our experimental proof of the reversible evolution from monopole to string sheds new light on topological defects and establishes the emergent monopole lattice as a new 3D topological phase.

4.
J Sci Food Agric ; 104(3): 1668-1678, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37847204

RESUMO

BACKGROUND: Hemp protein isolates (HPIs), which provide a well-balanced profile of essential amino acids comparable to other high-quality proteins, have recently garnered significant attention. However, the underutilized functional attributes of HPIs have constrained their potential commercial applications within the food and agriculture field. This study advocates the utilization of dynamic-high-pressure-microfluidization (DHPM) for the production of stable high-internal-phase emulsions (HIPEs), offering an efficient approach to fully exploit the potential of HPI resources. RESULTS: The findings underscore the effectiveness of DHPM in producing HPI as a stabilizing agent for HIPEs with augmented antioxidant activity. Microfluidized HPI exhibited consistent adsorption and anchoring at the oil-water interface, resulting in the formation of a dense and compact layer. Concurrently, the compression of droplets within HIPEs gave rise to a polyhedral framework, conferring viscoelastic properties and a quasi-solid behavior to the emulsion. Remarkably, HIPEs stabilized by microfluidized HPI demonstrated superior oxidative and storage stability, attributable to the establishment of an antioxidative barrier by microfluidized HPI particles. CONCLUSION: This study presents an appealing approach for transforming liquid oils into solid-like fats using HPI particles, all without the need for surfactants. HIPEs stabilized by microfluidized HPI particles hold promise as emerging food ingredients for the development of emulsion-based formulations with enhanced oxidative stability, thereby finding application in the food and agricultural industries. © 2023 Society of Chemical Industry.


Assuntos
Cannabis , Emulsões/química , Excipientes , Oxirredução , Antioxidantes/metabolismo , Estresse Oxidativo , Tamanho da Partícula
5.
Cell ; 135(1): 110-22, 2008 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-18854159

RESUMO

Stromal interaction molecule-1 (STIM1) activates store-operated Ca2+ entry (SOCE) in response to diminished luminal Ca2+ levels. Here, we present the atomic structure of the Ca2+-sensing region of STIM1 consisting of the EF-hand and sterile alpha motif (SAM) domains (EF-SAM). The canonical EF-hand is paired with a previously unidentified EF-hand. Together, the EF-hand pair mediates mutually indispensable hydrophobic interactions between the EF-hand and SAM domains. Structurally critical mutations in the canonical EF-hand, "hidden" EF-hand, or SAM domain disrupt Ca2+ sensitivity in oligomerization via destabilization of the entire EF-SAM entity. In mammalian cells, EF-SAM destabilization mutations within full-length STIM1 induce punctae formation and activate SOCE independent of luminal Ca2+. We provide atomic resolution insight into the molecular basis for STIM1-mediated SOCE initiation and show that the folded/unfolded state of the Ca2+-sensing region of STIM is crucial to SOCE regulation.


Assuntos
Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Sequência de Aminoácidos , Animais , Sinalização do Cálcio/genética , Análise Mutacional de DNA , Motivos EF Hand , Células HeLa , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Alinhamento de Sequência , Molécula 1 de Interação Estromal
6.
Eur Spine J ; 32(11): 3875-3884, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37740786

RESUMO

This paper presents a comparison of quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA) in osteoporosis with vertebral fracture and osteoporosis without fracture. It has been proved that the volumetric bone mineral density (vBMD) measured by QCT exhibits a stronger correlation with fracture risk than areal bone mineral density (aBMD) measured by DXA. PURPOSE: This study aims to systematically evaluate the ability of QCT and DXA to distinguish between osteoporosis with vertebral fracture and osteoporosis without fracture according to vBMD and aBMD. METHODS: We conducted a primary literature search of the online databases up to 3 July, 2022, in both English and Chinese publications, combining synonyms for "QCT", "DXA" and "osteoporosis". The Newcastle-Ottawa scale (NOS) was employed to evaluate the quality of the selected articles. vBMD obtained through QCT and aBMD obtained through DXA were extracted, and were analyzed by Review Manager 5.4 and RStudio. RESULTS: Six studies with 610 individuals aged 45 to 90, of which 179 had vertebral fractures, were included in the final analysis. The weighted mean difference (WMD) between osteoporosis with vertebral fracture and osteoporosis without fracture for vBMD was - 27.08 (95% CI - 31.24 to - 22.92), while for aBMD was - 0.05 (95% CI - 0.08 to - 0.03). CONCLUSIONS: Both vBMD detected by QCT and aBMD detected by DXA could discriminate fracture status in the spine, and vBMD performed a stronger correlation with fracture risk. TRIAL REGISTRATION: PROSPERO 2022 CRD42022349185.


Assuntos
Osteoporose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Densidade Óssea , Absorciometria de Fóton/métodos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/epidemiologia , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/epidemiologia , Osteoporose/complicações , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Coluna Vertebral , Tomografia Computadorizada por Raios X/métodos , Vértebras Lombares
7.
Ann Hum Biol ; 50(1): 35-41, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36636009

RESUMO

BACKGROUND: Known for its rich history and culture, Qingdao is a typical symbol of Chinese maritime culture. Its unique genetic landscape has aroused interest among geneticists and forensic scientists. However, the genetic landscape of Qingdao has never been uncovered. AIM: This investigation intends to provide light on Qingdao's paternal genetic diversity and its evolutionary connections to other Han subgroups. SUBJECTS AND METHODS: The genetic polymorphisms of 41 Y-chromosomal short tandem repeat (STR) loci in the Qingdao Han were investigated using SureID® PathFinder Plus Kit. Phylogenetic studies were performed using genotype data from 52 East Asian groups at 23 common Y-STR loci. A multidimensional scaling plot and cladogram were constructed. Linear Discriminant Analysis (LDA) was carried out for predicting categories among the Han people. The k-nearest neighbour (kNN) algorithm was utilised to designate Y-SNP haplogroups for each haplotype. RESULTS: The Qingdao Han were genetically far from the Tibeto-Burman populations and close with the Han people from northern China. LDA indicated a deep integration among the present-day Han people. By the kNN model, the predicted O2a2 and O2a1 were shown to be the predominant Y-SNP haplogroups. CONCLUSIONS: This study would be helpful for reconstructing the patrilineal history in China and establishing a more comprehensive Y-STR database.


Assuntos
Etnicidade , Genética Populacional , Humanos , Filogenia , Etnicidade/genética , Cromossomos Humanos Y/genética , Haplótipos , China , Repetições de Microssatélites/genética , Frequência do Gene
8.
Nano Lett ; 22(9): 3737-3743, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35451843

RESUMO

A major challenge in topological magnetism lies in the three-dimensional (3D) exploration of their magnetic textures. A recent focus has been the question of how 2D skyrmion sheets vertically stack to form distinct types of 3D topological strings. Being able to manipulate the vertical coupling should therefore provide a route to the engineering of topological states. Here, we present a new type of axially bound magnetic skyrmion string state in which the strings in two distinct materials are glued together across their interface. With quasi-tomographic resonant elastic X-ray scattering, the 3D skyrmion profiles before and after their binding across the interface were unambiguously determined and compared. Their attractive binding is accompanied by repulsive twisting; i.e., the coupled skyrmions mutually affect each other via a compensating twisting. This state exists in chiral magnet-magnetic thin film heterostructures, providing a new arena for the engineering of 3D topological phases.

9.
J Sci Food Agric ; 103(5): 2544-2553, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36571448

RESUMO

BACKGROUND: The application of curcumin (CUR) in the food industry is limited by its instability, hydrophobicity and low bioavailability. Yeast cell protein (YCP) is a by-product of spent brewer's yeast, which has the potential to deliver bioactive substances. However, the environmental stresses such as pH, salt and heat treatment has restricted its application in the food industry. Maillard reaction as a non-enzymatic browning reaction can improve protein stability under environmental stress. RESULTS: The CUR was successfully encapsulated into the hydrophobic core of YCP/glycated YCP (GYCP) and enhanced by hydrogen bonding, resulting in static fluorescence quenching of YCP/GYCP. The average diameter and dispersibility of GYPC-CUR nanocomplex were significantly improved after glucose glycation (121.40 nm versus 139.70 nm). Moreover, the encapsulation capacity of CUR was not influenced by glucose glycation. The oxidative stability and bioaccessibility of CUR in nanocomplexes were increased compared with free CUR, especially complexed with GYCP conjugates. CONCLUSION: Steric hindrance provided by glucose conjugation improved the enviriomental stability, oxidative activity and bioaccessibility of CUR in nanocomplexes. Thus, glucose-glycated YCP has potential application as a delivery carrier for hydrophobic compounds in functional foods. © 2022 Society of Chemical Industry.


Assuntos
Antineoplásicos , Curcumina , Nanopartículas , Curcumina/química , Antioxidantes , Saccharomyces cerevisiae , Reação de Maillard , Antineoplásicos/química , Tamanho da Partícula , Nanopartículas/química
10.
Zhongguo Zhong Yao Za Zhi ; 48(5): 1229-1237, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37005807

RESUMO

Eleutherococcus senticosus is one of the Dao-di herbs in northeast China. In this study, the chloroplast genomes of three E. senticosus samples from different genuine producing areas were sequenced and then used for the screening of specific DNA barcodes. The germplasm resources and genetic diversity of E. senticosus were analyzed basing on the specific DNA barcodes. The chloroplast genomes of E. senticosus from different genuine producing areas showed the total length of 156 779-156 781 bp and a typical tetrad structure. Each of the chloroplast genomes carried 132 genes, including 87 protein-coding genes, 37 tRNAs, and 8 rRNAs. The chloroplast genomes were relatively conserved. Sequence analysis of the three chloroplast genomes indicated that atpI, ndhA, ycf1, atpB-rbcL, ndhF-rpl32, petA-psbJ, psbM-psbD, and rps16-psbK can be used as specific DNA barcodes of E. senticosus. In this study, we selected atpI and atpB-rbcL which were 700-800 bp and easy to be amplified for the identification of 184 E. senticosus samples from 13 genuine producing areas. The results demonstrated that 9 and 10 genotypes were identified based on atpI and atpB-rbcL sequences, respectively. Furthermore, the two barcodes identified 23 genotypes which were named H1-H23. The haplotype with the highest proportion and widest distribution was H10, followed by H2. The haplotype diversity and nucleotide diversity were 0.94 and 1.82×10~(-3), respectively, suggesting the high genetic diversity of E. senticosus. The results of the median-joining network analysis showed that the 23 genotypes could be classified into 4 categories. H2 was the oldest haplotype, and it served as the center of the network characterized by starlike radiation, which suggested that population expansion of E. senticosus occurred in the genuine producing areas. This study lays a foundation for the research on the genetic quality and chloroplast genetic engineering of E. senticosus and further research on the genetic mechanism of its population, providing new ideas for studying the genetic evolution of E. senticosus.


Assuntos
Código de Barras de DNA Taxonômico , Eleutherococcus , Eleutherococcus/genética , Sequência de Bases , Cloroplastos/genética , Variação Genética , Filogenia
11.
J Am Chem Soc ; 144(12): 5418-5423, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35230846

RESUMO

Merging existing catalysts together as a cascade catalyst may achieve "one-pot" synthesis of complex but functional molecules by simplifying multistep reactions, which is the blueprint of sustainable chemistry with low pollutant emission and consumption of energy and materials only when the smooth mass exchange between different catalysts is ensured. Effective strategies to facilitate the mass exchange between different active centers, which may dominate the final activity of various cascade catalysts, have not been reached until now, even though charged interfaces due to work function driven electron exchange have been widely observed. Here, we successfully constructed mass (reactants and intermediates) exchange paths between Pd/N-doped carbon and MoC/N-doped carbon induced by interfacial electron exchange to trigger the mild and cascade methylation of amines using CO2 and H2. Theoretical and experimental results have demonstrated that the mass exchange between electron-rich MoC and electron-deficient Pd could prominently improve the production of N,N-dimethyl tertiary amine, which results in a remarkably high turnover frequency value under mild conditions, outperforming the state-of-the-art catalysts in the literature by a factor of 5.9.


Assuntos
Dióxido de Carbono , Elétrons , Aminas/química , Carbono/química , Dióxido de Carbono/química , Catálise
12.
Small ; 18(19): e2200885, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35396794

RESUMO

Solar-driven production of hydrogen peroxide (H2 O2 ), as an important industrial chemical oxidant with an extensive range of applications, from oxygen reduction is a sustainable alternative to mainstream anthraquinone oxidation and direct hydrogenation of dioxygen methods. The efficiency of solar to hydrogen peroxide over semiconductor-based photocatalysts is still largely limited by the narrow light absorption to visible light. Here, the authors proposed and demonstrate the proof-of-concept application of light-generated hot electrons in a graphene/semiconductor (exemplified with widely used TiO2 ) dyad to largely extend visible light spectra up to 800 nm for efficient H2 O2 production. The well-designed graphene/semiconductor heterojunction has a rectifying interface with a zero barrier for the hot electron injection, largely boosting excited hot electrons with an average lifetime of ≈0.5 ps into charge carriers with a long fluorescent lifetime (4.0 ns) for subsequent H2 O2 production. The optimized dyadic photocatalyst can provide an H2 O2 yield of 0.67 mm g-1  h-1 under visible light irradiation (λ ≥ 400 nm), which is 20 times of the state-of-the-art noble-metal-free titanium oxide-based photocatalyst, and even achieves an H2 O2 yield of 0.14 mm g-1  h-1 upon photoexcitation by near-infrared-region light (≈800 nm).

13.
J Viral Hepat ; 29(3): 196-204, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34902216

RESUMO

Liver steatosis is becoming increasingly common in patients with chronic hepatitis B (CHB), and its effect on liver stiffness measurement (LSM), as assessed by transient elastography, remains controversial. Seven hundred and fifty-five patients with CHB and normal serum alanine aminotransferase levels, who underwent vibration-controlled transient elastography and liver biopsy, were included in the study. We examined whether the histological degree of liver steatosis affects the accuracy of transient elastography-assessed LSM in these patients. Among the 755 CHB patients included in the study, 286 (37.9%) had liver steatosis, of whom 156 had grade S1, 74 had grade S2, and 56 had grade S3 on histology. Presence of liver steatosis was independently associated with greater body mass index (BMI, adjusted-odds ratio [OR] = 5.786, 95% CI: 3.998-8.373, p = 0.018), and higher serum total cholesterol (adjusted-OR = 7.944, 95% CI: 4.731-13.339, p < 0.001) and triglyceride levels (adjusted-OR = 2.777, 95% CI: 2.050-3.761, p < 0.001). There was no significant association between liver steatosis and fibrosis stage (OR = 1.016, 95% CI: 0.905-1.140, p = 0.790). Age (B-coefficient = 0.020, 95% CI: 0.001-0.040, p = 0.044), BMI (B-coefficient = 0.060, 95% CI: 0.011-0.127, p = 0.019), serum gamma-glutamyl-transpeptidase (GGT, B-coefficient = 0.015, 95% CI: 0.001-0.029, p = 0.032), positivity for HBeAg (B-coefficient = -0.816, 95% CI: -1.568 to -0.064, p = 0.034), as well as liver fibrosis stage (B-coefficient = 2.796, 95% CI: 2.501-3.090, p < 0.001), and inflammation activity grade (B-coefficient = 0.648, 95% CI: 0.162-1.135, p = 0.009) were all independently associated with higher LSM, while no significant association was found between degree of liver steatosis and LSM. Among patients with the same histological fibrosis stage, LSM values did not show any significant difference among patients with absent, mild, moderate or severe steatosis. We conclude that liver steatosis has no significant effect on transient elastography-measured LSM in CHB patients with normal serum alanine aminotransferase levels.


Assuntos
Técnicas de Imagem por Elasticidade , Fígado Gorduroso , Hepatite B Crônica , Alanina Transaminase , Estudos de Coortes , Fígado Gorduroso/patologia , Hepatite B Crônica/complicações , Hepatite B Crônica/patologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/complicações
14.
Int J Legal Med ; 136(2): 551-553, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34510269

RESUMO

In respect of forensic genetics, X-STRs are widely applied for deficiency paternity cases. Given the popularization of AGCU-X19 STR Kit in China, there has been investigation conducted into the genetic data and forensic parameters of 19 X-STR loci in many of the Chinese ethnic groups, which makes it possible to perform nationwide phylogenetic comparation. To evaluate the allele and haplotype diversity of 19 X-STR loci and to explore their forensic efficiency in the Daur and Oroqen minorities, unrelated healthy Daur (n = 86) and Oroqen (n = 165) individuals were recruited from Heilongjiang province, so as to reveal the phylogenetic relationship between the two minorities and other Chinese ethnic groups. Of the Daur and Oroqen minorities, 172 and 183 alleles at the 19 X-STR loci were observed, respectively. Haplotype diversity exceeded 0.9 among all the linkage clusters. High cumulative value was observed for the power of discrimination, the probability of exclusion, and the mean exclusion chance for deficiency cases (normal trios and duo cases). As revealed by this study, the panel of 19 X-STR loci is an effective supplementary tool for the kinship test of the studied nationalities.


Assuntos
Etnicidade , Repetições de Microssatélites , China , Cromossomos Humanos X , Etnicidade/genética , Frequência do Gene , Genética Populacional , Humanos , Filogenia , Polimorfismo Genético
15.
Neoplasma ; 69(5): 1041-1053, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35723199

RESUMO

Laryngeal squamous cell carcinoma (LSCC) is one of the most prevalent malignant diseases worldwide. LSCC patients suffer from a severe decline in life quality, due to the essential roles of the larynx in basic functions in the human body. The overarching goal of the present study is to explore whether exosome from M2 macrophages promotes LSCC by targeting glycolysis. In the current study, the expression of PDLIM2, an E3 ubiquitin ligase, in clinical samples was monitored by quantitative PCR and immunohistochemical examination. Extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) were measured by the Seahorse machine. Cell proliferation was measured by using Cell Counting Kit-8. A luciferase assay was performed to verify the regulation of miRNA on its target gene. The results showed that PDLIM2 exhibited downregulation in LSCC clinical samples and was associated with stage and differentiation of tumors in patients. In FaDu cell line, PDLIM2 inhibited cell proliferation and glycolysis but promoted the ubiquitination of PFKL. Exosomes from M2-type macrophages delivered miR-222-3p into LSCC cells to suppress PDLIM2 expression, leading to the elevated expression of PFKL and enhanced glycolysis which accelerated the proliferation of FaDu cells. The findings from cultured cells were supported by a subcutaneous tumor growth model in nude mice. Collectively, our data provided a snapshot of the miR-222-3p/PDLIM2/PFKL axis in LSCC tumorigenesis, and in concert with the importance of TAM exosomes and glycolysis, could be potentially translated to LSCC clinics.


Assuntos
Carcinoma de Células Escamosas , Exossomos , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , MicroRNAs , Proteínas Adaptadoras de Transdução de Sinal , Animais , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glicólise , Neoplasias de Cabeça e Pescoço/genética , Humanos , Proteínas com Domínio LIM , Neoplasias Laríngeas/patologia , Macrófagos , Camundongos , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Ubiquitina-Proteína Ligases/genética
16.
Bioprocess Biosyst Eng ; 45(11): 1857-1864, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36153378

RESUMO

To simulate acetate consumption and electricity generation in a cycle of a microbial fuel cell (MFC) treating synthetic acetate-based wastewater with low concentration, nonelectrogenic bacteria (NEB), which had no contribution in electricity generation, was incorporated with methanogen's kinetic parameters into a previous biofilm model proposed by Marcus et al. (Biotechnol Bioeng 98:1171-1182, 2007). However, the Coulombic efficiency was estimated to be 40.1%, whereas the experiment showed 13.6%, as the presence of NEB was obviously underestimated. Thus, the maximum NEB reaction rate (qmaxC) was temporarily calibrated, and a sensitivity analysis was then conducted. As a result, the growth parameters of NEB, the growth of the exoelectrogenic bacteria, and the biofilm detachment were identified as influential parameters. qmaxC and a half rate constant of NEB (KsC) were selected as potential calibration parameters. The two sets of calibrated parameters (0.342 mmol-acetate (Ac)/mg-volatile solids (VS)/d of qmaxC and 33.8 mg-carbon (C)/L of KsC; 0.274 mmol-Ac/mg-VS/d of qmaxC and 16.9 mg-C/L of KsC) showed a good agreement with the experimental results at 100 mg-C/L of initial acetate. However, the calibrated parameter values obviously differed from those in previous models. The calibrated model also showed good agreement with the experimental results at 50 and 200 mg-C/L of the initial acetate. In view of the different values of qmaxC and KsC from those of methanogenic bacteria in previous models and the previous findings on anode microbial community, which showed that NEB are not only methanogenic bacteria, we concluded that the diversity of NEB should be considered to simulate performances in a cycle of MFC treating low organic matter concentrations.


Assuntos
Fontes de Energia Bioelétrica , Fontes de Energia Bioelétrica/microbiologia , Eletricidade , Bactérias/metabolismo , Eletrodos , Acetatos/metabolismo
17.
J Environ Manage ; 323: 116191, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36108510

RESUMO

This study investigates whether a novel estimation method based on machine learning can feasibly predict the readily biodegradable chemical oxygen demand (RB-COD) and slowly biodegradable COD (SB-COD) in municipal wastewater from the oxidation-reduction potential (ORP) data of anoxic batch experiments. Anoxic batch experiments were conducted with highly mixed liquor volatile suspended solids under different RB-COD and SB-COD conditions. As the RB-COD increased, the ORP breakpoint appeared earlier, and fermentation occurred in the interior of the activated sludge, even under anoxic conditions. Therefore, the ORP decline rates before and after the breakpoint were significantly correlated with the RB-COD and SB-COD, respectively (p < 0.05). The two biodegradable CODs were estimated separately using six machine learning models: an artificial neural network (ANN), support vector regression (SVR), an ANN-based AdaBoost, a SVR-based AdaBoost, decision tree, and random forest. Against the ORP dataset, the RB-COD and SB-COD estimation correlation coefficients of SVR-based AdaBoost were 0.96 and 0.88, respectively. To identify which ORP data are useful for estimations, the ORP decline rates before and after the breakpoint were separately input as datasets to the estimation methods. All six machine learning models successfully estimated the two biodegradable CODs simultaneously with accuracies of ≥0.80 from only ORP time-series data. Sensitivity analysis using the Shapley additive explanation method demonstrated that the ORP decline rates before and after the breakpoint obviously contributed to the estimation of RB-COD and SB-COD, respectively, indicating that acquiring the ORP data with various decline rates before and after the breakpoint improved the estimations of RB-COD and SB-COD, respectively. This novel estimation method for RB-COD and SB-COD can assist the rapid control of biological wastewater treatment when the biodegradable organic matter concentration dynamically changes in influent wastewater.


Assuntos
Esgotos , Águas Residuárias , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Aprendizado de Máquina , Oxigênio , Esgotos/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise
18.
Zhongguo Zhong Yao Za Zhi ; 47(7): 1814-1823, 2022 Apr.
Artigo em Zh | MEDLINE | ID: mdl-35534251

RESUMO

Scutellaria baicalensis is a commonly used Chinese medicinal herb. In this study, we identified the germplasm resources of commercial S. baicalensis samples based on trnH-psbA, petA-psbJ, and ycf4-cemA sequences according to the available chloroplast genome sequencing results, and measured the content of baicalin by HPLC. Through the above means we determined the best DNA barcode that can be used to detect the germplasm resources and evaluate the quality of commercial S. baicalensis samples. A total of 104 samples were collected from 24 provinces, from which DNA was extracted for PCR amplification. The amplification efficiencies of trnH-psbA, petA-psbJ, and ycf4-cemA sequences were 100%, 59.62%, and 25.96%, respectively. The results of sequence analysis showed that 5, 4, and 2 haplotypes were identified based on trnH-psbA, petA-psbJ, and ycf4-cemA sequences, respectively. However, the sequences of haplotypes in commercial samples were different from that of the wild type, and the joint analysis of three fragments of S. baicalensis only identified 6 haplotypes. Furthermore, the phylogenetic analysis and genetic distance analysis indicated that trnH-psbA could be used to identify S. baicalensis from adulterants. The above analysis showed that trnH-psbA was the best fragment for identifying the germplasm resources of commercial S. baicalensis samples. We then analyzed the haplotypes(THap1-THap5) of commercial S. baicalensis samples based on trnH-psbA and found that THap2 was the main circulating haplotype of the commercial samples, accounting for 86.55% of the total samples, which indicated the scarce germplasm resources of commercial S. baicalensis samples. The content of baicalin in all the collected commercial S. baicalensis samples exceeded the standard in Chinese Pharmacopoeia and had significant differences(maximum of 12.21%) among samples, suggesting that the quality of commercial S. baicalensis samples varied considerably. However, there was no significant difference in baicalin content between different provinces or between different haplotypes. This study facilitates the establishment of the standard identification system for S. baicalensis, and can guide the commercial circulation and reasonable medication of S. baicalensis.


Assuntos
Código de Barras de DNA Taxonômico , Scutellaria baicalensis , Cromatografia Líquida de Alta Pressão , Código de Barras de DNA Taxonômico/métodos , DNA de Plantas/genética , Filogenia , Scutellaria baicalensis/genética
19.
Angew Chem Int Ed Engl ; 61(35): e202207108, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35789523

RESUMO

Production of more than 20 million tons of epoxides per year from olefins suffers from low atom economy due to the use of oxidants and complex catalysts with unsatisfactory selectivity, leading to huge environmental and economic costs. We present a proof-of-concept application of electron-rich RuO2 nanocrystals to boost the highly selective epoxidation of cyclooctene via direct oxygen transfer from water as the sole oxygen source under mild conditions. The enhanced electron enrichment of RuO2 nanocrystals via the Schottky effect with nitrogen-doped carbons largely promotes the capture and activation of cyclooctene to give a high turnover frequency (260 h-1 ) of cyclooctene oxide, far surpassing the reported values (<20 h-1 ) of benchmarked catalysts at room temperature with oxidants. Our electron-rich RuO2 electrocatalysts enable efficient and durable hydrogen production (Faradaic efficiency >90 %) on the cathode without impacting on the selectivity to epoxide (>99 %) on the anode.

20.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(7): 821-825, 2022 Jul 15.
Artigo em Zh | MEDLINE | ID: mdl-35894200

RESUMO

OBJECTIVES: To explore the effect of polydatin on the proliferation and apoptosis of acute monocytic leukemia cell line THP-1 and the possible mechanism. METHODS: After THP-1 cells were treated with polydatin at gradient concentrations for 24 hours and 48 hours, their proliferation was determined by CCK-8 assay, and half maximal inhibitory concentration (IC50) was calculated. Logarithmically growing THP-1 cells were divided into two groups, a polydatin treatment group (treated with IC50 of polydatin) and a blank control group (treated without polydatin solution), and incubated for 48 hours. Cell apoptosis and cell cycle were measured by flow cytometry. The expression levels of PI3K, AKT, p-AKT, mTOR, p-mTOR, p70 S6K, and p-p70 S6K proteins were measured by Western blotting. RESULTS: After treatment with polydatin, the proliferation of THP-1 cells was strongly inhibited, and the IC50 at 48 hours was 1 800 µmol/L. After treatment with 1 800 µmol/L polydatin solution for 48 hours, the apoptosis rate of THP-1 cells increased significantly compared with the blank control group (P<0.05). The cell cycle was arrested in the G0/G1 and S phases, with a significantly increased proportion of cells in the G0/G1 phase and a significantly decreased proportion of cells in the S phase, as compared with the blank control group (P<0.05). The expression levels of PI3K, AKT, p-AKT, mTOR, p-mTOR, p70 S6K, and p-p70 S6K proteins decreased significantly compared with the blank control group (P<0.05). CONCLUSIONS: Polydatin can effectively inhibit the proliferation, block the cell cycle, and induce the apoptosis of THP-1 cells, which may be related to inhibition of the PI3K/AKT/mTOR signaling pathway.


Assuntos
Glucosídeos , Fosfatidilinositol 3-Quinases , Estilbenos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Glucosídeos/farmacologia , Humanos , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Estilbenos/farmacologia , Células THP-1 , Serina-Treonina Quinases TOR
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