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1.
Microb Ecol ; 86(4): 2756-2769, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37542537

RESUMO

Permafrost active layer soils are harsh environments with thaw/freeze cycles and sub-zero temperatures, harboring diverse microorganisms. However, the distribution patterns, assembly mechanism, and driving forces of soil microeukaryotes in permafrost remain largely unknown. In this study, we investigated microeukaryotes in permafrost active layer across the Qinghai-Tibet Plateau (QTP) using 18S rRNA gene sequencing. The results showed that the microbial eukaryotic communities were dominated by Nematozoa, Ciliophora, Ascomycota, Cercozoa, Arthropoda, and Basidiomycota in terms of relative abundance and operational taxonomic unit (OTU) richness. Nematozoa had the highest relative abundance, while Ciliophora had the highest OTU richness. These phyla had strong interactions between each other. Their alpha diversity and community structure were differently influenced by the factors associated to location, climate, and soil properties, particularly the soil properties. Significant but weak distance-decay relationships with different slopes were established for the communities of these dominant phyla, except for Basidiomycota. According to the null model, community assemblies of Nematozoa and Cercozoa were dominated by heterogeneous selection, Ciliophora and Ascomycota were dominated by dispersal limitation, while Arthropoda and Basidiomycota were highly dominated by non-dominant processes. The assembly mechanisms can be jointly explained by biotic interactions, organism treats, and environmental influences. Modules in the co-occurrence network of the microeukaryotes were composed by members from different taxonomic groups. These modules also had interactions and responded to different environmental factors, within which, soil properties had strong influences on these modules. The results suggested the importance of biological interactions and soil properties in structuring microbial eukaryotic communities in permafrost active layer soil across the QTP.


Assuntos
Artrópodes , Cilióforos , Microbiota , Pergelissolo , Animais , Tibet , Solo/química , Microbiologia do Solo , Cilióforos/genética
2.
Arch Virol ; 168(2): 76, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709234

RESUMO

Porcine circovirus-like virus (PCLV) is a recently discovered virus that may be associated with diarrhea in pigs. To investigate the epidemic profile and genetic characteristics of this virus, 175 clinical samples (141 intestinal samples, 17 blood samples, and 17 fecal samples) were collected from diseased piglets during outbreaks of diarrhea from 33 pig farms in 19 cities of Henan and Shanxi provinces of China between 2016 and 2021 and were screened by PCR for the presence of PCLV. The results showed that the positive rate for PCLV was 32% (56/175) at the sample level, 60.6% (20/33) at the farm level, and 57.9% (11/19) at the city level, which varied from 5.88% to 44.12% between 2016 and 2021. It was also found that PCLV occurred in coinfections with porcine circovirus type 2 (PCV2), PCV3, PCV4, porcine epidemic diarrhea virus, and porcine reproductive and respiratory syndrome virus, but no nucleic acids were detected for transmissible gastroenteritis virus, porcine deltacoronavirus, or porcine rotavirus in piglets with diarrhea. Notably, PCLV was detected in 13 diarrheal piglets from four different farms that were negative for the other porcine viruses. These findings suggest that PCLV may be associated with porcine diarrhea and that it has been circulating in piglets in Henan and Shanxi provinces of China. In addition, the complete genomes of 13 PCLV strains were sequenced and found to share 35.4%-91.0% nucleotide sequence identity with sequences available in the GenBank database. Phylogenetic analysis based on Rep amino acid sequences revealed that the 13 PCLV strains from this study clustered in group 1 and were closely related to eight Chinese PCLV strains, Bo-Circo-like virus CH, American strains 21 and 22, and Hungarian strains 288_4 and 302_4, but they differed genetically from seven other foreign PCLV strains. The whole genome and rep gene of 13 PCLV strains in this study were 72.2%-82% and 83.8%-89.7% identical, respectively, to those of Bo-Circo-like virus strain CH, indicating that PCLV is a novel virus in pigs that may be involved in cross-species transmission. Evidence of a recombination event was found in the rep region of the 13 PCLV strains sequenced. This study enriches the epidemiological data on PCLV infection in pigs in China and lays a foundation for further study on the pathogenesis of PCLV.


Assuntos
Infecções por Circoviridae , Circovirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Suínos , Animais , Circovirus/genética , Filogenia , Diarreia/epidemiologia , Diarreia/veterinária , Vírus da Diarreia Epidêmica Suína/genética , Reação em Cadeia da Polimerase , China/epidemiologia , Doenças dos Suínos/epidemiologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária
3.
Arch Virol ; 168(6): 161, 2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37179263

RESUMO

Porcine circovirus 4 (PCV4) is a recently discovered circovirus that was first reported in 2019 in several pigs in Hunan province of China and has also been identified in pigs infected with porcine epidemic diarrhea virus (PEDV). To further investigate the coinfection and genetic diversity of these two viruses, 65 clinical samples (including feces and intestinal tissues) were collected from diseased piglets on 19 large-scale pig farms in Henan province of China, and a duplex SYBR Green I-based quantitative real-time polymerase chain reaction (qPCR) assay was developed for detecting PEDV and PCV4 simultaneously. The results showed that the limit of detection was 55.2 copies/µL and 44.1 copies/µL for PEDV and PCV4, respectively. The detection rate for PEDV and PCV4 was 40% (26/65) and 38% (25/65), respectively, and the coinfection rate for the two viruses was 34% (22/65). Subsequently, the full-length spike (S) gene of eight PEDV strains and a portion of the genome containing the capsid (Cap) gene of three PCV4 strains were sequenced and analyzed. Phylogenetic analysis showed that all of the PEDV strains from the present study clustered in the G2a subgroup and were closely related to most of the PEDV reference strains from China from 2011 to 2021, but they differed genetically from a vaccine strain (CV777), a Korean strain (virulent DR1), and two Chinese strains (SD-M and LZC). It is noteworthy that two PEDV strains (HEXX-24 and HNXX-24XIA) were identified in one sample, and the HNXX-24XIA strain had a large deletion at amino acids 31-229 of the S protein. Moreover, a recombination event was observed in strain HEXX-24. Phylogenetic analysis based on the amino acid sequence of the PCV4 Cap protein revealed that PCV4 strains were divided into three genotypes: PCV4a1, PCV4a2, and PCV4b. Three strains in the present study belonged to PCV4a1, and they had a high degree of sequence similarity (>98% identity) to other PCV4 reference strains. This study not only provides technical support for field investigation of PEDV and PCV4 coinfection but also provides data for their prevention and control.


Assuntos
Circovirus , Coinfecção , Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Suínos , Filogenia , Circovirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/prevenção & controle , China/epidemiologia
4.
Crit Rev Food Sci Nutr ; : 1-19, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35980144

RESUMO

The gut microbiota (GM) is a complex ecosystem that is closely linked to host health. Ganoderma spp. polysaccharides (GPs), a major bioactive component of the fungal genus Ganoderma, can modulate the GM, exhibiting various health effects and prebiotic potential. This review comprehensively concluded the structural features and extraction method of GPs. The mechanism of GPs for anti-obesity, anti-diabetes, anti-inflammatory, and anti-cancer were further evaluated. The simulated gastrointestinal digestion of GPs and the utilization mechanism of host microorganisms were discussed. It was found that the physicochemical properties and biological activities of GPs depend on their structural characteristics (molecular weight, monosaccharide composition, glycosidic bonds, etc.). Their extraction method also affects the structure and bioactivities of polysaccharides. GPs supplementation could increase the relative abundance of beneficial bacteria (e.g. Bacteroides, Parabacteroides, Akkermansia, and Bifidobacterium), while reducing that of pathogenic bacteria (e.g. Aerococcus, Ruminococcus), thus promoting health. Moreover, GPs are resistant to digestion in the stomach and small intestine but are digested in the large intestine. Therefore, GPs can be considered as potential prebiotics. However, further studies should investigate how GPs as prebiotics regulate GM and improve host health.

5.
Mol Cell Probes ; 61: 101790, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35051595

RESUMO

PCV2 is one of the most economically important viral agents in swine worldwide. Recently, PCV3 has been frequently reported, and the co-infection of PCV2 and PCV3 is common in China. In order to explore the distribution, epidemiology and genetic diversity of PCV2 and PCV3, a total of 1,760 clinical tissue samples were randomly collected from 18 different regions in Henan province of China from October 2018 to September 2019 and screened for the presence of PCV2 and PCV3 by a duplex real-time PCR assay. The results showed that the positive rates of PCV2 and PCV3 were 72.90% and 5.17% respectively, and the co-infection rate of the two viruses was 3.64%. PCV2 and PCV3 are prevalent all year round. The prevalence of PCV2 in diseased pigs was 83.98%, higher than that in slaughterhouse pigs, while the prevalence of PCV3 in diseased pigs was 2.16%, slightly lower than that in slaughterhouse pigs. Furthermore, the complete genomes of 14 PCV2 and 3 PCV3 strains were obtained, among which 1 belonged to PCV2a, 5 belonged to PCV2b and 8 belonged to PCV2d. A new variant strain (XX2) might escape the host immune system. The phylogenetic analysis of PCV3 showed high nucleotide identity (>98%) between sequences obtained in this study and reference sequences. The results of this study might enrich the epidemiological data of PCV2 and PCV3 in Henan province and provide reference information for the comprehensive prevention and control of PCVAD.


Assuntos
Infecções por Circoviridae , Circovirus , Coinfecção , Doenças dos Suínos , Animais , China/epidemiologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária , Circovirus/genética , Genótipo , Filogenia , Suínos , Doenças dos Suínos/epidemiologia
6.
Gen Physiol Biophys ; 41(1): 15-30, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35253647

RESUMO

Chronic pancreatitis (CP), a fibroinflammatory disease, is a potential risk factor for pancreatic cancer. This study attempted to identify and analyze the key genes involved in CP development and their association with pancreatic cancer. The GSE41418 dataset was obtained from the Gene Expression Omnibus database. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed on common differentially expressed genes. A protein-protein interaction network was constructed by using the STRING database. The expression and prognostic value of hub genes in pancreatic cancer were analyzed by Gene Expression Profiling Interactive Analysis (GEPIA) and UALCAN databases. The results showed that the upregulated genes primarily focused on the cell cycle, DNA replication, and phagosome activity. The PPI network was composed of 184 nodes and 925 edges. The 10 hub genes were screened by CytoHubba, of which CCNB2, CDC6, CDK1 and CKS2 were observed to be differentially expressed in pancreatic cancer with CP, and all of them were detrimental to overall survival and recurrence-free survival of pancreatic cancer. In this study, we employed bioinformatic analysis to determine that CCNB2, CDC6, CDK1 and CKS2 may be key genes in the development of CP and pancreatic cancer.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Neoplasias Pancreáticas , Pancreatite Crônica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Quinases relacionadas a CDC2 e CDC28/genética , Quinases relacionadas a CDC2 e CDC28/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Biologia Computacional/métodos , Regulação Neoplásica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Humanos , Neoplasias Pancreáticas/genética , Pancreatite Crônica/genética
7.
J Ind Microbiol Biotechnol ; 47(12): 1083-1097, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33191463

RESUMO

D-Limonene, a cyclized monoterpene, possesses citrus-like olfactory property and multi-physiological functions, which can be used as a bioactive compound and flavor to improve the overall quality of alcoholic beverages. In our previous study, we established an orthogonal pathway of D-limonene synthesis by introducing neryl diphosphate synthase 1 (tNDPS1) and D-limonene synthase (tLS) in Saccharomyces cerevisiae. To further increase D-limonene formation, the metabolic flux of the mevalonate (MVA) pathway was enhanced by overexpressing the key genes tHMGR1, ERG12, IDI1, and IDI1WWW, respectively, or co-overexpressing. The results showed that strengthening the MVA pathway significantly improved D-limonene production, while the best strain yielded 62.31 mg/L D-limonene by co-expressing tHMGR1, ERG12, and IDI1WWW genes in alcoholic beverages. Furthermore, we also studied the effect of enhancing the MVA pathway on the growth and fermentation of engineered yeasts during alcoholic beverage fermentation. Besides, to further resolve the problem of yeast growth inhibition, we separately investigated transporter proteins of the high-yielding D-limonene yeasts and the parental strain under the stress of different D-limonene concentration, suggesting that the transporters of Aus1p, Pdr18p, Pdr5p, Pdr3p, Pdr11p, Pdr15p, Tpo1p, and Ste6p might play a more critical role in alleviating cytotoxicity and improving the tolerance to D-limonene. Finally, we verified the functions of three transporter proteins, finding that the transporter of Aus1p failed to transport D-limonene, and the others (Pdr5p and Pdr15p) could improve the tolerance of yeast to D-limonene. This study provided a valuable platform for other monoterpenes' biosynthesis in yeast during alcoholic beverage fermentation.


Assuntos
Fermentação , Limoneno , Ácido Mevalônico , Saccharomyces cerevisiae , Bebidas Alcoólicas , Liases Intramoleculares , Limoneno/metabolismo , Engenharia Metabólica , Ácido Mevalônico/metabolismo , Monoterpenos/metabolismo , Fosfatos de Poli-Isoprenil , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
8.
J Ind Microbiol Biotechnol ; 47(6-7): 511-523, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32495196

RESUMO

d-Limonene, a cyclic monoterpene, possesses citrus-like olfactory property and multi-physiological functions. In this study, the d-limonene synthase (tLS) from Citrus limon was codon-optimized and heterologously expressed in Saccharomyces cerevisiae. The metabolic flux of canonical pathway based on overexpressing endogenous geranyl diphosphate synthase gene (ERG20) and its variant ERG20F96W-N127W was strengthened for improvement d-limonene production in Chinese Baijiu. To further elevate production, we established an orthogonal pathway by introducing neryl diphosphate synthase 1 (tNDPS1) from Solanum lycopersicum. The results showed that expressing ERG20 and ERG20F96W-N127W could enhance d-limonene synthesis, while expressing heterologous NPP synthase gene significantly increase d-limonene formation. Furthermore, we constructed a tLS-tNDPS1 fusion protein, and the best strain yielded 9.8 mg/L d-limonene after optimizing the amino acid linker and fusion order, a 40% improvement over the free enzymes during Chinese Baijiu fermentation. Finally, under the optimized fermentation conditions, a maximum d-limonene content of 23.7 mg/L in strain AY12α-L9 was achieved, which was the highest reported production in Chinese Baijiu. In addition, we also investigated that the effect of d-limonene concentration on yeast growth and fermentation. This study provided a meaningful insight into the platform for other valuable monoterpenes biosynthesis in Chinese Baijiu fermentation.


Assuntos
Bebidas , Limoneno/metabolismo , Engenharia Metabólica , Saccharomyces cerevisiae/metabolismo , Dimetilaliltranstransferase/metabolismo , Fermentação , Microbiologia Industrial , Liases Intramoleculares/metabolismo , Fosfatos de Poli-Isoprenil/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
9.
Int J Neurosci ; 130(5): 454-460, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31822157

RESUMO

Background and Objective: Transient ischemic attack (TIA) is a serious condition that is often called a warning stroke. The risk of cerebral infarction in patients with TIA and positive DWI findings is greater than that in patients with TIA and normal DWI findings. Butylphthalide injection is a new type of brain protective drug. The study aimed to determine the efficacy and safety of butylphthalide injection for treating TIA as shown by DWI abnormality progressing to infarction.Methods: We studied 98 patients with positive DWI findings among 260 patients with TIA, and randomly divided into the experimental (treatment with butylphthalide injection) and control (treatment with aspirin) groups. The number of cerebral infarctions in the two groups was recorded on 7th, 14th, 30th and 90th day, and adverse reactions were observed. The number of cerebral infarctions was compared among the different ABCD2 scores of patients with TIA and positive DWI findings.Results: The incidence of cerebral infarction in the experimental group was significantly lower than that in the control group (p < .05). The incidence of cerebral infarction with an ABCD2 score less than 3 points was significantly lower than that with an ABCD2 score of more than 3 points (p < .05), with less adverse reactions.Conclusion: Butylphthalide injection is helpful and safe for preventing stroke following TIA, and treating TIA with positive DWI and progression to infarction.


Assuntos
Benzofuranos/farmacologia , Infarto Encefálico/diagnóstico por imagem , Infarto Encefálico/prevenção & controle , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzofuranos/administração & dosagem , Benzofuranos/efeitos adversos , Infarto Encefálico/epidemiologia , Infarto Encefálico/etiologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Injeções , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/epidemiologia , Masculino , Pessoa de Meia-Idade , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/efeitos adversos , Índice de Gravidade de Doença
10.
J Mol Cell Cardiol ; 130: 131-139, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30935996

RESUMO

Abdominal aortic aneurysm (AAA) is a life-threatening vascular disease without an effective pharmaceutical treatment. Liver kinase B1 (LKB1), a tumor suppressor, is a central regulator of cell polarity and energy homeostasis. However, the role of LKB1 in the development of AAA has not been explored. In this study, mice with knockout of smooth muscle-specific LKB1 (LKB1SMKO) were generated by cross-breeding LKB1flox/flox mice with SM22-CreERT2 transgenic mice and induced in adult mice by tamoxifen treatment. LKB1 deficiency increased the expression of matrix metalloproteinase 2 (MMP-2), which was inhibited by LKB1 overexpression. Mechanistically, LKB1 could bind to the MMP-2 transcription factor, specificity protein 1 (Sp1), thereby reducing the binding of Sp1 to the MMP-2 promoter to inhibit MMP-2 expression. LKB1 expression was significantly reduced in abdominal aortas of the mouse AAA model. Moreover, smooth muscle-specific LKB1 deletion exaggerated angiotensin II-induced AAA formation accompanied by increased AAA incidence and aortic expansion. Finally, LKB1 level was significantly lower and MMP-2 level higher in human AAA samples than adjacent nonaneurysmal aortic sections. Thus, these results suggest that LKB1 may play a protective role in AAA formation by inhibiting MMP-2 expression and could be a potential therapeutic target for AAA disease.


Assuntos
Aneurisma da Aorta Abdominal/enzimologia , Músculo Liso Vascular/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases Ativadas por AMP , Angiotensina II/efeitos adversos , Angiotensina II/farmacologia , Animais , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/patologia , Modelos Animais de Doenças , Deleção de Genes , Humanos , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/genética , Camundongos , Camundongos Knockout , Músculo Liso Vascular/patologia , Proteínas Serina-Treonina Quinases/genética , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo
11.
J Cell Mol Med ; 22(3): 1475-1488, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29266779

RESUMO

Diabetic cardiomyopathy, a major cardiac complication, contributes to heart remodelling and heart failure. Our previous study discovered that CCAAT/enhancer-binding protein ß (C/EBPß), a transcription factor that belongs to a family of basic leucine zipper transcription factors, interacts with the angiotensin-converting enzyme 2 (ACE2) promoter sequence in other disease models. Here, we aimed to determine the role of C/EBPß in diabetes and whether ACE2 expression is regulated by C/EBPß. A type 1 diabetic mouse model was generated by an intraperitoneal injection of streptozotocin. Diabetic mice were injected with a lentivirus expressing either C/EBPß or sh-C/EBPß or treated with valsartan after 12 weeks to observe the effects of C/EBPß. In vitro, cardiac fibroblasts and cardiomyocytes were treated with high glucose (HG) to investigate the anti-fibrosis, anti-apoptosis and regulatory mechanisms of C/EBPß. C/EBPß expression was down-regulated in diabetic mice and HG-induced cardiac neonatal cells. C/EBPß overexpression significantly attenuated collagen deposition and cardiomyocyte apoptosis by up-regulating ACE2 expression. The molecular mechanism involved the binding of C/EBPß to the ACE2 promoter sequence. Although valsartan, a classic angiotensin receptor blocker, relieved diabetic complications, the up-regulation of ACE2 expression by C/EBPß overexpression may exert greater beneficial effects on patients with diabetic cardiomyopathy.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/genética , Diabetes Mellitus Experimental/terapia , Cardiomiopatias Diabéticas/prevenção & controle , Fibroblastos/metabolismo , Miócitos Cardíacos/metabolismo , Peptidil Dipeptidase A/genética , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Enzima de Conversão de Angiotensina 2 , Animais , Apoptose/genética , Glicemia/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/antagonistas & inibidores , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular , Colágeno/antagonistas & inibidores , Colágeno/genética , Colágeno/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/patologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica , Glucose/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Peptidil Dipeptidase A/metabolismo , Cultura Primária de Células , Ligação Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Estreptozocina , Valsartana/farmacologia
12.
Nat Commun ; 15(1): 5747, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982069

RESUMO

Friction as a fundamental physical phenomenon dominates nature and human civilization, among which the achievement of molecular rolling lubrication is desired to bring another breakthrough, like the macroscale design of wheel. Herein, an edge self-curling nanodeformation phenomenon of graphite nanosheets (GNSs) at cryogenic temperature is found, which is then used to promote the formation of graphite nanorollers in friction process towards molecular rolling lubrication. The observation of parallel nanorollers at the friction interface give the experimental evidence for the occurrence of molecular rolling lubrication, and the graphite exhibits abnormal lubrication performance in vacuum with ultra-low friction and wear at macroscale. The molecular rolling lubrication mechanism is elucidated from the electronic interaction perspective. Experiments and theoretical simulations indicate that the driving force of the self-curling is the uneven atomic shrinkage induced stress, and then the shear force promotes the intact nanoroller formation, while the constraint of atomic vibration decreases the dissipation of driving stress and favors the nanoroller formation therein. It will open up a new pathway for controlling friction at microscale and nanostructural manipulation.

13.
Int J Radiat Oncol Biol Phys ; 119(3): 978-989, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38159780

RESUMO

PURPOSE: Implementing artificial intelligence technologies allows for the accurate prediction of radiation therapy dose distributions, enhancing treatment planning efficiency. However, esophageal cancers present unique challenges because of tumor complexity and diverse prescription types. Additionally, limited data availability hampers the effectiveness of existing artificial intelligence models. This study developed a deep learning model, trained on a diverse data set of esophageal cancer prescriptions, to improve dose prediction accuracy. METHODS AND MATERIALS: We retrospectively collected data from 530 patients with esophageal cancer, including single-target and simultaneous integrated boost prescriptions, for model building. The proposed Asymmetric ResNeSt (AS-NeSt) model features novel 3-dimensional (3D) ResNeSt blocks and an asymmetrical architecture. We constructed a loss function targeting global and local doses and validated the model's performance against existing alternatives. Model-assisted experiments were used to validate its clinical benefits. RESULTS: The AS-NeSt model maintained an absolute prediction error below 5% for each dosimetric metric. The average Dice similarity coefficient for isodose volumes was 0.93. The model achieved an average relative prediction error of 2.02%, statistically lower than Hierarchically Densely Connected U-net (4.17%), DoseNet (2.35%), and Densely Connected Network (3.65%). It also demonstrated significantly fewer parameters and shorter prediction times. Clinically, the AS-NeSt model raised physicians' ability to accurately preassess appropriate treatment methods before planning from 95.24% to 100%, reduced planning time by over 61% for junior dosimetrists and 52% for senior dosimetrists, and decreased both inter- and intra-dosimetrist discrepancies by more than 50%. CONCLUSIONS: The AS-NeSt model, developed with innovative 3D ResNeSt blocks and an asymmetrical encoder-decoder structure, has been validated using clinical esophageal cancer patient data. It accurately predicts 3D dose distributions for various prescriptions, including simultaneous integrated boost, showing potential to improve the management of esophageal cancer treatment in a clinical setting.


Assuntos
Aprendizado Profundo , Neoplasias Esofágicas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/patologia , Humanos , Estudos Retrospectivos , Planejamento da Radioterapia Assistida por Computador/métodos
14.
Eur Heart J Case Rep ; 7(4): ytad168, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37090760

RESUMO

Background: Percutaneous transluminal septal myocardial ablation (PTSMA) is an effective means for symptomatic patients with hypertrophic cardiomyopathy (HCM). We present a rare case in which myocardial bridge (MB) was exacerbated in a patient with HCM treated with PTSMA. Case summary: Here, we present a case of HCM with palpitations and exertional dyspnoea for 2 years. There was no obvious epicardial coronary artery compression before PTSMA. Typical angina occurred 2 months after PTSMA. Coronary angiography showed no obvious stenosis of the coronary arteries, but an exacerbated MB in the middle part of the left anterior descending artery. Discussion: This patient with HCM presented with typical angina, which might be caused by the rare exacerbation of the MB after PTSMA. Thus, patients with MB should carefully choose PTSMA. Future research is needed for HCM patients complicated with MB treated with PTSMA.

15.
Nutrients ; 15(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36839197

RESUMO

Probiotics have received wide attention as a potential way to alleviate gastrointestinal (GI) motility disorders. Herein, we investigated the effects of Lacticaseibacillus paracasei JY062, Lactobacillus gasseri JM1, and the probiotic combination at 5 × 109 CFU/mL on mice induced by loperamide and explored the possible underlying mechanisms in GI motility disorder. After two weeks of probiotic intervention, the results indicated that the probiotic combination alleviated GI motility disorder better. It increased the secretion of excitatory GI regulators motilin, gastrin, and 5-hydroxytryptamine (5-HT) and decreased the secretion of the inhibitory GI regulators peptide YY and nitric oxide (NO), except vasoactive intestinal peptide. 5-HT and NO were related to the mRNA expression of 5-HT4 receptor and nitric oxide synthase, respectively. The intervention of probiotic combination also increased the number of interstitial cells of Cajal and the expression of SCF/c-kit protein. In addition, it also increased the abundance of beneficial bacteria (Lactobacillus, Rikenellaceae, and Clostridiaceae_Clostridium) and improved the contents of short-chain fatty acids in cecum contents of mice. In conclusion, the probiotic combination of L. paracasei JY062 and L. gasseri JM1 has the potential to alleviate GI motility disorders by balancing intestinal homeostasis.


Assuntos
Gastroenteropatias , Microbioma Gastrointestinal , Lacticaseibacillus paracasei , Lactobacillus gasseri , Probióticos , Animais , Camundongos , Lacticaseibacillus , Serotonina , Probióticos/farmacologia , Motilidade Gastrointestinal
16.
Foods ; 12(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36900599

RESUMO

Cronobacter spp. is a food-borne pathogenic microorganism that can cause serious diseases such as meningitis, sepsis, and necrotizing colitis in infants and young children. Powdered infant formula (PIF) is one of the main contamination routes, in which the processing environment is an important source of pollution. In this investigation, 35 Cronobacter strains isolated from PIF and its processing environment were identified and typed by 16S rRNA sequencing and multilocus sequence typing (MLST) technology. A total of 35 sequence types were obtained, and three new sequence types were isolated for the first time. The antibiotic resistance was analyzed, showing that all isolates were resistant to erythromycin but sensitive to ciprofloxacin. Multi-drug resistant strains accounted for 68.57% of the total, among which Cronobacter strains with the strongest drug resistance reached 13 multiple drug resistance. Combined with transcriptomics, 77 differentially expressed genes related to drug resistance were identified. The metabolic pathways were deeply excavated, and under the stimulation of antibiotic conditions, Cronobacter strains can activate the multidrug efflux system by regulating the expression of chemotaxis-related genes, thus, secreting more drug efflux proteins to enhance drug resistance. The study of drug resistance of Cronobacter and its mechanism has important public health significance for the rational selection of existing antibacterial drugs, the development of new antibacterial drugs to reduce the occurrence of bacterial resistance, and the control and treatment of infections caused by Cronobacter.

17.
J Tradit Complement Med ; 13(4): 368-378, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37396156

RESUMO

Background and aim: Recent studies show that combination of apoptosis and oxidative stress forms a "vicious circle" in the process of premature ovarian failure (POF). Pearl extract has a good effect for anti-oxidation and anti-aging in vitro and vivo and can be used to treat various aging diseases. However, reports about effect and mechanism of pearl on ovarian function of premature ovarian failure (POF)are limited. Experimental procedure: The effect and mechanism of pearl on ovarian function of rats with POF were evaluated using rats with premature ovarian failure induced by tripterygium glycosides. The estrous cycle, contents of serum reproductive hormones, tissue structure, oxidative stress level, autophagy and apoptotic protein expression, and MAPK signaling pathway of ovary were assessed to characterise pearl. Result and conclusion: Low, medium and high-dose pearl improved the estrous cycle in POF rats, and high-dose pearl was the best in terms of recovery effect; high-dose pearl significantly increased (P < 0.05) contents of E2, AMH and GSH, activities of SOD, CAT and GSH-PX and follicular development, while significantly decreased (P < 0.05)contents of FSH, LH and ROS and MDA in POF rats; low, medium and high-dose pearl notably reduced (P < 0.05) the apoptotic protein cleaved-caspase 3 and Bax expression, and MAPK signaling pathway of ERK1/2, p38 and JNK in POF rats, among which high-dose pearl behaved best. Medium and high-dose pearl apparently raised (P < 0.05)expressions of autophagy protein LC3II, Beclin-1 and p62 in POF rats. Therefore, pearl can effectively enhance ovarian function of POF rats. The optimal concentration was found to be 740 mg kg-1 at a high dose. The mechanism may be related with the enhanced follicular development through improving granulosa cell autophagy and inhibiting granulosa cell apoptosis by inhibition of MAPK signaling pathway after scavenging excessive ROS. Section: 1. Natural Products. Taxonomy classification by EVISE: Ovarian Cancer, Chinese Herbal Medicine, Traditional Medicine, Oxidative Stress, Antioxidant Studies, Rat, Autophagy.

18.
Cell Death Dis ; 14(8): 542, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37607939

RESUMO

Foam cell formation is a hallmark of the early phase of atherosclerosis. Growing evidence has demonstrated that vascular smooth muscle cells (VSMCs) comprise a considerable proportion of foam cells. Liver kinase B1 (LKB1) plays a crucial part in cardiovascular diseases. However, the role of LKB1 in VSMC-derived foam cell formation and atherosclerosis remains unclear. To explore the effects of LKB1 on VSMC-derived foam cell formation and atherosclerosis, we generated smooth muscle-specific LKB1 knockout (LKB1SMKO) mice by crossbreeding LKB1flox/flox mice with SM22α-CreERT2 mice. LKB1 expression decreased in plaque-loaded aortas and oxidized low-density lipoprotein (oxLDL)-treated VSMCs. Compared with controls, atherosclerosis development was exacerbated in LKB1SMKO mice via the promotion of VSMC-derived foam cell formation. Conversely, LKB1 overexpression inhibited lipid uptake and foam cell formation in VSMCs. Mechanistically, LKB1 binds to SIRT6 and directly phosphorylates and activates it, thereby reducing lectin-like oxLDL receptor-1 (LOX-1) via SIRT6-dependent histone deacetylation. Finally, adeno-associated virus (AAV)-mediated LOX-1 deficiency in smooth muscle ameliorated atherosclerosis in LKB1SMKO mice. Our findings suggest that LKB1 may modulate VSMC-derived foam cell formation and atherosclerosis via the phosphorylation and activation of SIRT6.


Assuntos
Aterosclerose , Sirtuínas , Animais , Camundongos , Aterosclerose/genética , Células Espumosas , Fígado , Músculo Liso , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Sirtuínas/genética
19.
Microbiol Spectr ; : e0433322, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36728419

RESUMO

A novel circovirus species was identified in farmed pigs and designated porcine circovirus 4 (PCV4); it has recently been proved to be pathogenic to piglets. However, little is known about its cross-species transmission, and there is no evidence of PCV4 in dogs. A total of 217 fecal samples were collected from diarrheal dogs in Henan Province, China, and tested for the presence of PCV4 using a real-time PCR assay. Among the 217 samples, the total positivity rate for PCV4 was 5.99% (13/217 samples), with rates of 7.44% and 4.17% in 2020 and 2021, respectively. PCV4 was detected in dogs in 6 of 10 cities, demonstrating that PCV4 could be detected in dogs in Henan Province, China. One PCV4 strain (HN-Dog) was sequenced in this study and shared high levels of identity (97.9% to 99.6%) with reference strains at the genome level. Phylogenetic analysis based on complete genome sequences of HN-Dog and 42 reference strains showed that the HN-Dog strain was closely related to 3 PCV4 reference strains (from pig, raccoon dog, and fox) but differed genetically from other viruses in the genus Circovirus. Three genotypes, i.e., PCV4a, PCV4b, and PCV4c, were confirmed by phylogenetic analysis of complete genome sequences of 42 PCV4 strains, and one amino acid variation in Rep protein (V239L) and three amino acid variations in Cap protein (N27S, R28G, and M212L) were considered conserved genotype-specific molecular markers. In conclusion, the present study is the first to report the discovery of the PCV4 genome in dogs, and the association between PCV4 infection and diarrhea warrants further study. IMPORTANCE This study is the first to report the presence of PCV4 in dogs worldwide, and the first complete genome sequence was obtained from a dog affected with diarrhea. Three genotypes of PCV4 strains (PCV4a, PCV4b, and PCV4c) were determined, as supported by specific amino acid markers (V239L for open reading frame 1 [ORF1] and N27S R28G and M212L for ORF2). These findings help us understand the current status of intestinal infections in pet dogs in Henan Province, China, and also prompted us to accelerate research on the pathogenesis, epidemiology, and cross-species transmission of PCV4.

20.
Cancers (Basel) ; 15(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37686655

RESUMO

To develop accurate and accessible prediction methods for assessing pathologic response following NICT prior to surgery, we conducted a retrospective study including 137 patients with esophageal squamous cell carcinoma (ESCC) who underwent surgery after two cycles of NICT between January 2019 and March 2022 at our center. We collected clinical parameters to evaluate the dynamic changes in the primary tumor. Univariate and multivariate analyses were performed to determine the correlations between these parameters and the pathologic response of the primary tumor. Subsequently, we constructed prediction models for pCR and MPR using multivariate logistic regression. The MPR prediction Model 2 was internally validated using bootstrapping and externally validated using an independent cohort from our center. The univariate logistic analysis revealed significant differences in clinical parameters reflecting tumor regression among patients with varying pathologic responses. The clinical models based on these assessments demonstrated excellent predictive performance, with the training cohort achieving a C-index of 0.879 for pCR and 0.912 for MPR, while the testing cohort also achieved a C-index of 0.912 for MPR. Notably, the MPR prediction Model 2, with a threshold cut-off of 0.74, exhibited 92.7% specificity and greater than 70% sensitivity, indicating a low rate of underestimating residual tumors. In conclusion, our study demonstrated the high accuracy of clinical assessment-based models in pathologic response prediction, aiding in decision-making regarding organ preservation and radiotherapy adjustments after induction immunochemotherapy.

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