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1.
Curr Opin Neurobiol ; 77: 102628, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36116166

RESUMO

Perception is internally constructed by integrating brain states with external sensory inputs, a process depending on the topdown modulation of sensory representations. A wealth of earlier studies described task-dependent modulations of sensory cortex corroborating perceptual and behavioral phenomena. But only with recent technological advancements, the underlying circuit-level mechanisms began to be unveiled. We review recent progress along this line of research. It begins to be appreciated that topdown signals can encode various types of task-related information, ranging from task engagement, and category knowledge to decision execution; these signals are transferred via feedback pathways originating from distinct association cortices and interact with sensory cortical circuits. These plausible mechanisms support a broad range of computations from predictive coding to inference making, ultimately form dynamic percepts and endow behavioral flexibility.

2.
Vet Microbiol ; 274: 109574, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36126504

RESUMO

Porcine parvovirus (PPV) is an important pathogen causing reproductive disorders in first pregnant sows. The non-structure protein NS1 of PPV is a multifunctional protein playing a key role in viral replication. Chaperonin-containing T-complex polypeptide complex (CCT), containing CCT1-CCT8 subunits, belongs to the type II chaperones that interact with proteins to help in folding and maintaining. In this study, CCT5, for the first time, was found to be one of the host interacting proteins of PPV NS1, and CCT5 was directly bound with NS1. Interference of CCT5 expression by specific siRNA and knockout of CCT5 expression by CRISPR/Cas9 suppressed PPV replication, while overexpression of CCT5 promoted PPV replication in PK-15 cells. The interaction of CCT5 and PPV NS1 was dependent on the 36-42 aa motif at the N-terminal end of NS1. More importantly, CCT5 was also found interacting with COPƐ, which has previously been demonstrated to promote PPV replication by regulating type I interferon. Interference and knockout of CCT5 expression significantly reduced the interaction of PPV NS1 and host protein COPƐ, and promoted the IFN-ß expression. These results show that CCT5 mediates the interaction of PPV NS1 and COPƐ to regulate viral replication, providing new insight into the mechanism of PPV replication.

3.
World Neurosurg ; 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36126894

RESUMO

BACKGROUND: To visualize the course of the tympanic segment of chorda tympani nerve (CTN) using ultra-high-resolution computed tomography (U-HRCT). METHODS: A hundred and fourteen ears with no evident otologic pathologies were included. The tympanic segment of CTN was divided into four portions: periannular, posteromalleal, malleal, and anteromalleal. The length of the periannular portion running along the tympanic annulus was recorded. Four points of interest (the beginning and end of the posteromalleal and anteromalleal portions) were selected to perform distance measurements relative to the tip of the malleus manubrium. Differences in lengths and distances were compared in terms of ear sides and sexes. RESULTS: The length of the periannular portion was 2.49 ± 1.16 mm. The beginning of the posteromalleal portion was located more laterally on the right side than on the left side (mean: 4.09 mm vs. 3.92 mm, P = 0.016). The end of the posteromalleal portion was located more inferiorly on the right (mean: 2.11 mm vs. 2.26 mm, P = 0.018). The beginning of the anteromalleal portion on the right was located more laterally than that on the left (mean: 2.60 mm vs. 2.45 mm, P = 0.027). The start and end of the anteromalleal portion were more posteriorly located in women than in men (both Ps < 0.001). CONCLUSIONS: The course of the tympanic segment of normal CTN was comprehensively visualized by U-HRCT. Preoperative evaluation of the tympanic segment of CTN might be helpful in avoiding iatrogenic injury during middle ear surgery.

4.
Front Pharmacol ; 13: 967670, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110538

RESUMO

Hemerocallis citrina Baroni [Asphodelaceae], which is traditional herbal medicine, has been widely used for treating depressive disorders in Eastern-Asia countries. However, the active compounds and corresponding mechanism of anti-depression are not yet completely clarified. In this study, the anti-depressive activities of six H. citrina extracts were primarily evaluated. The results showed that the water extract of H. citrina flowers (HCW) displays significant anti-depressive activity. A total of 32 metabolites were identified from HCW by high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS) and nuclear magnetic resonance (NMR). And then, the anti-depressive activity of the high-level compound (rutin) in HCW was also estimated. The results indicated that rutin displayed significant anti-depressive activity and was one of the main active ingredients. Finally, the anti-depressive mechanisms of HCW and rutin were investigated based on the intestinal microorganisms. The results showed that HCW and rutin increase the diversity and richness of the intestinal flora and regulate the specific intestinal microorganisms such as Bacteroides and Desulfovibrio genera in depressed mice. This work marks the first comprehensive study of the active components, anti-depressive activities and corresponding mechanisms of different H. citrina extracts, which provide a potential possibility for developing new antidepressants.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36054401

RESUMO

Multi-label learning focuses on the ambiguity at the label side, i.e., one instance is associated with multiple class labels, where the logical labels are always adopted to partition class labels into relevant labels and irrelevant labels rigidly. However, the relevance or irrelevance of each label corresponding to one instance is essentially relative in real-world tasks and the label distribution is more fine-grained than the logical labels by denoting one instance with a certain number of the description degrees of all class labels. As the label distribution is not explicitly available in most training sets, a process named label enhancement emerges to recover the label distributions in training datasets. By inducing the generative model of the label distribution and adopting the variational inference technique, the approximate posterior density of the label distributions should maximize the variational lower bound. Following the above consideration, LEVI is proposed to recover the label distributions from the training examples. In addition, the multi-label predictive model is induced for multi-label learning by leveraging the recovered label distributions along with a specialized objective function. The recovery experiments on fourteen label distribution datasets and the predictive experiments on fourteen multi-label learning datasets validate the advantage of our approach over the state-of-the-art approaches.

6.
Intervirology ; 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36103866

RESUMO

The novel coronavirus (COVID-19 or 2019-nCoV) is a respiratory virus that can exist in the mouth and saliva of patients and spreads through aerosol dispersion. Therefore, stomatological hospitals and departments have become high-infection-risk environments. Accordingly, oral disinfectants that can effectively inactivate the virus have become a highly active area of research. Hexadecyl pyridinium chloride, povidone-iodine, and other common oral disinfectants are the natural primary choices for stomatological hospitals. Therefore, this study investigated the inhibitory effect of hexadecyl pyridinium chloride on SARS-CoV-2 in vitro. Vero cells infected with SARS-CoV-2 were used to determine the disinfection effect; the CCK-8 method was used to determine cytotoxicity, and viral load was determined by real-time PCR. The results showed that hexadecyl pyridinium chloride has no obvious cytotoxic effect on Vero cells in the concentration range 0.0125-0.05 mg/mL. The in vitro experiments showed that hexadecyl pyridinium chloride significantly inhibits the virus at concentrations of 0.1 mg/mL or above at 2 min of action. Thus, the results provide experimental support for the use of hexadecyl pyridinium chloride in stomatological hospitals.

7.
Artigo em Inglês | MEDLINE | ID: mdl-35964262

RESUMO

Polymalic acid (PMA) is a water-soluble polyester produced by Aureobasidium pullulans. In this study, the physiological response of A. pullulans after the addition of vegetable oils was investigated. Soybean oil (SBO) is pivotal for shortening fermentation time and achieving high PMA titer. With the addition of 1% (w/v) SBO, the titer and productivity of PMA was, respectively, increased by 34.2% and 80%. SBO acted as a chemical stimulatory agent rather than a carbon source, the enhancement on PMA production was attributed to the component of fatty acid. SBO induced the dimorphism (yeast-like cells and mycelia) of A. pullulans, in vitro enzyme activities indicated that the TCA oxidative branch for malic acid synthesis might be strengthened, which could generate more ATP for PMA synthesis, and the assay of intracellular energy supply validated this deduction. This study provided a new sight for recognizing the regulatory behavior of SBO in A. pullulans.

8.
Hematol Oncol ; 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36043430

RESUMO

We hypothesized that ruxolitinib may inhibit the immune checkpoint protein, B7H3; and, thus, investigated its effects on this immune inhibitor using multiple myeloma (MM) cell lines, bone marrow (BM) mononuclear cells from MM patients and human MM LAGλ -1A xenografts. Ruxolitinib reduced B7H3 gene and protein expression and increased IL-2 and CD8 gene expression. These results suggest that ruxolitinib inhibition of B7H3 may restore exhausted T-cell activity in the MM BM tumor microenvironment.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36012005

RESUMO

Territorial space is a multi-functional complex. The coordinated production-living-ecological space (PLES) effectively coordinates the man-land relationship, promotes regional sustainable development, and maximizes territorial space. How to build a high-quality national spatial layout and support system for development has become a hot topic of concern in all sectors of society. However, few studies have explored the coupling coordination considering the various production-living-ecological functions of land use type and its influencing factors of PLES at the county scale in China. To address the gap, based on the connotation of PLES theory, this study established a classification and evaluation system for PLES and analyzed the spatio-temporal characteristics, coupling coordination degree, spatial autocorrelation, and influencing factors of PLES in China from 2000 to 2020. The results are as follows: (1) The production space index and living space index in China showed a continuous increase tendency, while the ecological space index decreased continuously during the study period. The production space and living space were concentrated in the east of Hu Line, and the ecological space indexes in mountainous areas were significantly higher than those in plain areas during the study period. (2) The gravity centers of PLES all migrated to the west of China to different degrees during the study period. (3) From 2000 to 2020, the basically balanced category was the main coupling coordination type, and the number of seriously unbalanced categories accounted for the least. In the west of the Hu Line, the seriously unbalanced category was dominant, while in the east of the Hu Line were the moderately unbalanced categories and above. (4) During the study period, the low-low type was the main relationship type, widely distributed in western China, followed by the high-high type, mainly situated in the North China Plain, Yangtze River Delta, Pearl River Delta, Jianghan Plain, Chengdu Plain, Northeast China Plain, and some provincial capital cities. (5) Regression results showed that natural factors were the main reason restricting the coordinated development of PLES, and socioeconomic factors could effectively promote the coordinated development of PLES. Landscape pattern also significantly influenced the coordinated development of PLES, but varied greatly. The findings of this study can provide a scientific reference for the optimization of territorial space layout and the promotion of high-quality development of territorial space.


Assuntos
Conservação dos Recursos Naturais , Rios , China , Cidades , Desenvolvimento Econômico , Humanos , Análise Espacial , Urbanização
10.
Science ; 377(6609): 967-975, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-36007034

RESUMO

Chromosome engineering has been attempted successfully in yeast but remains challenging in higher eukaryotes, including mammals. Here, we report programmed chromosome ligation in mice that resulted in the creation of new karyotypes in the lab. Using haploid embryonic stem cells and gene editing, we fused the two largest mouse chromosomes, chromosomes 1 and 2, and two medium-size chromosomes, chromosomes 4 and 5. Chromatin conformation and stem cell differentiation were minimally affected. However, karyotypes carrying fused chromosomes 1 and 2 resulted in arrested mitosis, polyploidization, and embryonic lethality, whereas a smaller fused chromosome composed of chromosomes 4 and 5 was able to be passed on to homozygous offspring. Our results suggest the feasibility of chromosome-level engineering in mammals.


Assuntos
Fusão Gênica Artificial , Edição de Genes , Cariótipo , Translocação Genética , Animais , Fusão Gênica Artificial/métodos , Cromatina/química , Células-Tronco Embrionárias , Edição de Genes/métodos , Haploidia , Camundongos , Mitose
11.
Artigo em Inglês | MEDLINE | ID: mdl-36011547

RESUMO

The main function zone (MFZ) is the major strategy of China's economic development and ecological environment protection. Clarifying the logical relationship between "MFZ strategy" and "territorial spatial layout" is vital to construct regional economic layout and territorial spatial supporting system of high-quality development. However, few studies have revealed the evolution process and formation mechanism of the production-living-ecological space (PLES) structure of China's MFZ over a long period of time. To bridge the gap, based on the land use dataset in China from 1980 to 2020, this study analyzed the evolution patterns of PLES in China's MFZs using multiple methods and measured the formation mechanism of PLES in different types of MFZs with the GeoDetector model. Results showed that the spatial structure of China's national territory has evolved drastically in the past 40 years, showing significant horizontal regional differentiation and vertical gradient differentiation. Ecological space has been continuously decreasing, while production space and living space have been continuously increasing, and the evolution of PLES varied significantly in different MFZs. During the study period, the gravity center of PLES in China all moved westward. The spatial distribution pattern of production space and living space was from northeast to southwest, and the ecological space was from east to west. The evolution of China's territorial spatial structure was subject to the combined effects of natural and socio-economic factors, exhibiting significant differences in different MFZs. Land use intensity had the most prominent influence on the formation of PLES, followed by elevation. The influences of different factors on PLES structure were strengthened mainly through two types of nonlinear enhancement and dual-factor enhancement. This study can provide scientific support for the optimal management and high-quality development of territorial space in China.


Assuntos
Desenvolvimento Econômico , Meio Ambiente , China
12.
J Sci Food Agric ; 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36036167

RESUMO

BACKGROUND: Using transglutaminase (TGase) is a new method to improve protein properties in order to promote protein glycosylation. This article mainly studies soy protein isolate (SPI) and glucosamine to improve the freeze-thaw stability of emulsion under the action of TGase. The degree of glycosylation was studied by the content of free amino groups and the degree of conjugation. The optimal conditions for preparing soy protein isolate-glucosamine (SPI-G) conjugate were determined by a response surface optimization model based on single-factor experiments using the creaming index of the emulsion after the first freeze-thaw cycle as the response value. RESULTS: The results showed that the emulsion had the lowest creaming index when the conditions of protein concentration was 20 g L-1 , mass ratio of SPI-G was 5:3 (w/w), enzyme addition amount was 10 U g-1 , and reaction time was 2 h. The optimized modified product was measured for the creaming index after the first freeze-thaw cycle. It was found that the creaming index of the modified product SPI-G after the first freeze-thaw cycle was 9.02%, which was less than and close to the optimized model predicted value. The creaming index and optical microscopy results after three freeze-thaw cycles confirmed that the freeze-thaw stability of the SPI-G samples was significantly enhanced after optimization of the response surface model. CONCLUSION: It showed that glycosylation promoted by TGase could improve the freeze-thaw stability of SPI emulsion, thereby broadening the application of SPI in food. © 2022 Society of Chemical Industry.

13.
Metab Eng ; 73: 144-157, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35921946

RESUMO

Metabolic engineering seeks to rewire the metabolic network of cells for the efficient production of value-added compounds from renewable substrates. However, it remains challenging to evaluate and identify strains with the desired phenotype from the vast rational or random mutagenesis library. One effective approach to resolve this bottleneck is to design an efficient high-throughput screening (HTS) method to rapidly detect and analyze target candidates. L-cysteine is an important sulfur-containing amino acid and has been widely used in agriculture, pharmaceuticals, cosmetics, and food additive industries. However, HTS methods that enable monitoring of L-cysteine levels and screening of the enzyme variants and strains to confer superior L-cysteine biosynthesis remain unavailable, greatly limiting the development of efficient microbial cell factories for L-cysteine production at the industrial scale. Here, we took advantage of the L-cysteine-responsive transcriptional regulator CcdR to develop a genetically encoded biosensor for engineering and screening the L-cysteine overproducer. The in vivo L-cysteine-responsive assays and in vitro electrophoretic mobility shift assay (EMSA) and DNase I footprint analysis indicated that CcdR is a transcriptional activator that specifically interacts with L-cysteine and binds to its regulatory region to induce the expression of target genes. To improve the response performance of the L-cysteine biosensor, multilevel optimization strategies were performed, including regulator engineering by semi-rational design and systematic optimization of the genetic elements by modulating the promoter and RBS combination. As a result, the dynamic range and sensitivity of the biosensor were significantly improved. Using this the excellent L-cysteine biosensor, a HTS platform was established by coupling with fluorescence-activated cell sorting (FACS) and was successfully applied to achieve direct evolution of the key enzyme in the L-cysteine biosynthetic pathway to increase its catalytic performance and to screen the high L-cysteine-producing strains from the random mutagenesis library. These results presented a paradigm of design and optimization of biosensors to dynamically detect metabolite concentrations and provided a promising tool enabling HTS and metabolic regulation to construct L-cysteine hyperproducing strains to satisfy industrial demand.


Assuntos
Técnicas Biossensoriais , Cisteína , Técnicas Biossensoriais/métodos , Cisteína/genética , Ensaios de Triagem em Larga Escala , Engenharia Metabólica/métodos , Fatores de Transcrição/genética
15.
J Cereb Blood Flow Metab ; : 271678X221112278, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999817

RESUMO

Systemic inflammation affects cognitive functions and increases the risk of dementia. This phenomenon is thought to be mediated in part by cytokines that promote neuronal survival, but the continuous exposure to which may lead to neurodegeneration. The effects of systemic inflammation on cerebral blood vessels, and their provision of adequate oxygen to support critical brain parenchymal cell functions, remains unclear. Here, we demonstrate that neurovascular coupling is profoundly disturbed in lipopolysaccharide (LPS) induced systemic inflammation in awake mice. In the 24 hours following LPS injection, the hyperaemic response of pial vessels to functional activation was attenuated and delayed. Concurrently, under steady-state conditions, the capillary network displayed a significant increase in the number of capillaries with blocked blood flow, as well as increased duration of 'capillary stalls'-a phenomenon previously reported in animal models of stroke and Alzheimer's disease pathology. We speculate that vascular changes and impaired oxygen availability may affect brain functions following acute systemic inflammation and contribute to the long-term risk of neurodegenerative changes associated with chronic, systemic inflammation.

16.
J Environ Public Health ; 2022: 8351868, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35942141

RESUMO

Vocal music teaching resource databases can support teachers' instruction and students' learning while also enhancing the school's ability to run a school because they are the main components of digital construction for vocal music teaching. Currently, system application is the main area of research for DM (data mining), which was previously focused on method discovery. A vocal music teaching resource base based on DM technology is created by using the theme as the central organising principle, processing, and organising the resources. Incorporate lesson planning, teaching, self-study, and output resource construction into a digital network resource application environment by using thematic resource development. Students' achievement data, personal basic information, and evaluation data are used for DM based on the enhanced Apriori algorithm in order to uncover hidden rules and find correlations between various factors. This information is then used to support decision-making. When the system load is 1, the results demonstrate that the Apriori algorithm's CPU waste rate and task success rate is 0.144 and 0.896, respectively. The study's conclusion demonstrates that integrating DM technology into the field of education is theoretically and practically possible and that there is significant room for future study and application in this area.


Assuntos
Música , Mineração de Dados , Humanos , Instituições Acadêmicas , Estudantes , Tecnologia
17.
BMC Complement Med Ther ; 22(1): 209, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35932049

RESUMO

BACKGROUND: The Sheng-ji Hua-yu (SJHY) formula is a quite effective Traditional Chinese Medicines (TCM) in the treatment of delayed diabetic wounds. Previous research has shown that the SJHY formula has significant anti-inflammatory and wound-healing effects, but the precise mechanism remains unknown. The purpose of this study was to evaluate the effects of rhein, a compound extracted from SJHY formula, in keratinocytes and to investigate the underlying mechanisms. METHODS: Microscale thermophoresis (MST) technology was used to confirm that rhein binds directly to oestrogen receptors (ERs). Rhein was then used to treat keratinocytes in vitro. Cell cycle and proliferation analysis, Real-time polymerase chain reaction (RT-PCR) and Western-blot were conducted. RESULTS: Rhein increased the proportion of cells in the S phase of the cell cycle and promoted keratinocyte proliferation. ICI 182,780, an ER inhibitor, was also used to treat keratinocytes. The expression of c-myc mRNA and protein induced by rhein was antagonized by ICI 182,780, indicating that this induction is ER dependent. Intervention with ICI 182,780 had no effect on the upregulation of FosB and JunD, indicating that activator protein 1 (AP-1) members (FosB and JunD) are involved in rhein-induced c-myc mRNA and protein expression but does not require the ER. CONCLUSION: The present study found that rhein stimulates keratinocyte proliferation by activating the oestrogen signalling pathway via the oestrogen receptor, which induces the expression of c-myc in collaboration with FosB and JunD, thereby accelerating the process of re-epithelialization.


Assuntos
Antraquinonas/farmacologia , Receptores de Estrogênio , Úlcera Cutânea , Proliferação de Células , Fulvestranto/metabolismo , Fulvestranto/farmacologia , Humanos , Queratinócitos/metabolismo , RNA Mensageiro/metabolismo , Receptores de Estrogênio/metabolismo , Úlcera Cutânea/metabolismo
18.
Cell Death Discov ; 8(1): 351, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927229

RESUMO

Clear cell renal cell carcinoma (ccRCC) is one of the most common malignant tumors of the urinary system. Distant metastasis is the leading cause of poor prognosis in ccRCC. However, ccRCC is found poorly responsitive to radiotherapy and chemotherapy. Effective therapeutic strategies for its metastasis remain scarce. We analyzed clinical samples and public database, for differential expression of SLC27A2 and further explored its relationship with clinical prognosis. Biochemistry and functional experiments were carried out to study the potential mechanisms of SLC27A2, CDK3, and EMT. SLC27A2 was significantly downregulated in clinical specimens and renal cancer cell lines and predicted poor prognosis. We found that specific upregulation of SLC27A2 could significantly inhibited the proliferation, migration, and invasion of renal cancer cell lines. SLC27A2 could also influence the Epithelial-mesenchymal transition (EMT) signaling pathway, linked to the progression and metastasis of renal cancer. Using whole transcriptome sequencing of SLC27A2, CDK3 was identified as a regulatory SLC27A2 target. In terms of mechanism, SLC27A2 may further inhibit the epithelial-to-mesenchymal transition by negatively regulating CDK3. Our work suggests that functional inhibition of SLC27A2-CDK3-EMT axis may be an attractive therapeutic target for metastasis of ccRCC.

19.
Sci Adv ; 8(32): eabq0411, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-35960798

RESUMO

Radiative cooling and evaporative cooling with low carbon footprint are regarded as promising passive cooling strategies. However, the intrinsic limits of continuous water supply with complex systems for evaporative cooling, and restricted cooling power as well as the strict requirement of weather conditions for radiative cooling, hinder the scale of their practical applications. Here, we propose a tandem passive cooler composed of bilayer polymer that enables dual-functional passive cooling of radiation and evaporation. Specifically, the high reflectivity to sunlight and mid-infrared emissivity of this polymer film allows excellent radiative cooling performance, and its good atmospheric water harvesting property of underlayer ensures self-supply of water and high evaporative cooling power. Consequently, this tandem passive cooler overcomes the fundamental difficulties of radiative cooling and evaporative cooling and shows the applicability under various conditions of weather/climate. It is expected that this design can expand the practical application domain of passive cooling.

20.
Case Rep Surg ; 2022: 8311278, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35978861

RESUMO

Postoperative surgical site infection is one of the serious postoperative complications of spine surgery, especially fungal infections. Late-stage surgical site fungal infections often lack typical clinical symptoms and have a variable clinical presentation. In this case, the patient was a senior patient with usually only tolerable pain and discomfort, which was detected 2 years after the first surgery. Such cases are even rarer for fungal bloodstream infections caused by delayed postoperative chronic fungal osteomyelitis and deserve further study for early identification and intervention to minimize harm.

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