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1.
World J Psychiatry ; 14(5): 644-652, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38808092

RESUMEN

BACKGROUND: Cerebral infarction (CI) is characterized by a high prevalence, disability, and mortality. Timely or improper treatment greatly affects patient prognosis. AIM: To explore the drug efficacy of aspirin plus edaravone and to explore their effect on quality of life (QOL), anxiety and depression in CI patients. METHODS: We retrospectively analyzed the records of 124 CI patients treated between June 2019 and February 2021 who were assigned to an observation group (OG) (combination therapy of aspirin and edaravone, 65 patients) or a control group (CG) (aspirin monotherapy, 59 patients). The therapeutic effects, pre- and posttreatment National Institutes of Health Stroke Scale (NIHSS) scores, activities of daily living, degree of cognitive impairment, protein levels of glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE) and S-100B, occurrence of adverse reactions, and serum high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6 and tumor necrosis factor (TNF)-α were evaluated, detected and compared between the two groups. Finally, posttreatment QOL, anxiety, and depression were assessed by the Medical Outcomes Study 36- Item Short Form Health Survey Scale, Self-rating Depression Scale (SDS), and Self-rating Anxiety Scale (SAS), respectively. RESULTS: Compared with the CG, the OG had markedly better therapeutic effects, greater improvements in activities of daily living, and better alleviation in cognitive dysfunction after treatment, as well as lower posttreatment NIHSS scores and serum NSE, GFAP, S-100B, hs-CRP, IL-6, and TNF-α levels; the OG was similar to the CG in terms of adverse reactions but was better than the CG in terms of posttreatment QOL; and the OG also had lower SDS and SAS scores than the CG after treatment. CONCLUSION: Aspirin plus edaravone had a good curative effect on CI. It can reverse cranial nerve damage in patients, improve neurological function and prognosis, and alleviate inflammation, anxiety, and depression; thus, it is considered safe and worthy of clinical application.

2.
Appl Microbiol Biotechnol ; 108(1): 347, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38805033

RESUMEN

Crop roots selectively recruit certain microbial taxa that are essential for supporting their growth. Within the recruited microbes, some taxa are consistently enriched in the rhizosphere across various locations and crop genotypes, while others are unique to specific planting sites or genotypes. Whether these differentially enriched taxa are different in community composition and how they interact with nutrient cycling need further investigation. Here, we sampled bulk soil and the rhizosphere soil of five soybean varieties grown in Shijiazhuang and Xuzhou, categorized the rhizosphere-enriched microbes into shared, site-specific, and variety-specific taxa, and analyzed their correlation with the diazotrophic communities and microbial genes involved in nitrogen (N) cycling. The shared taxa were dominated by Actinobacteria and Thaumarchaeota, the site-specific taxa were dominated by Actinobacteria in Shijiazhuang and by Nitrospirae in Xuzhou, while the variety-specific taxa were more evenly distributed in several phyla and contained many rare operational taxonomic units (OTUs). The rhizosphere-enriched taxa correlated with most diazotroph orders negatively but with eight orders including Rhizobiales positively. Each group within the shared, site-specific, and variety-specific taxa negatively correlated with bacterial amoA and narG in Shijiazhuang and positively correlated with archaeal amoA in Xuzhou. These results revealed that the shared, site-specific, and variety-specific taxa are distinct in community compositions but similar in associations with rhizosphere N-cycling functions. They exhibited potential in regulating the soybean roots' selection for high-efficiency diazotrophs and the ammonia-oxidizing and denitrification processes. This study provides new insights into soybean rhizosphere-enriched microbes and their association with N cycling. KEY POINTS: • Soybean rhizosphere affected diazotroph community and enriched nifH, amoA, and nosZ. • Shared and site- and variety-specific taxa were dominated by different phyla. • Rhizosphere-enriched taxa were similarly associated with N-cycle functions.


Asunto(s)
Bacterias , Glycine max , Rizosfera , Microbiología del Suelo , Glycine max/microbiología , Glycine max/crecimiento & desarrollo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Raíces de Plantas/microbiología , Ciclo del Nitrógeno , Nitrógeno/metabolismo , Archaea/genética , Archaea/clasificación , Archaea/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Fijación del Nitrógeno , Oxidorreductasas/genética , Microbiota
3.
Opt Express ; 32(4): 5908-5921, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439306

RESUMEN

We present an all-fiber passively mode-locked (ML) laser with a nonlinear multimode interference (NLMI)-based saturable absorber (SA) capable of generating five pulse modes. The SA consists of two centrally aligned graded index multimode fiber (GIMF) with different diameters (105-50 µm) and features a widely adjustable transmission with saturable/reverse-saturable absorption. Based on this, dissipative soliton (DS), Q-switched rectangular pulse (QRP), dissipative soliton resonance (DSR), noise-like pulse (NLP) and bright-dark pulse pairs (BDP) are observed at three dispersions without additional filter. The DS has a pulse energy, bandwidth and duration of up to 1.15 nJ, 17.98 nm and ∼2.78 ps. The achievable pulse duration and energy of DSR and NLP are 5.21, 48.06 ns and 4.53, 5.12 nJ, respectively. Furthermore, it is demonstrated that the BDP is superimposed by a chair-case pulse (CP) and a rectangular pulse (RP) belonging to orthogonal polarization states. The versatility, flexibility, simplicity and energy scalability of the large-core hybrid GIMF-SA, make it interesting and highly attractive in ultrafast photonics.

4.
BMC Bioinformatics ; 25(1): 35, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38254030

RESUMEN

BACKGROUND: Natural proteins occupy a small portion of the protein sequence space, whereas artificial proteins can explore a wider range of possibilities within the sequence space. However, specific requirements may not be met when generating sequences blindly. Research indicates that small proteins have notable advantages, including high stability, accurate resolution prediction, and facile specificity modification. RESULTS: This study involves the construction of a neural network model named TopoProGenerator(TPGen) using a transformer decoder. The model is trained with sequences consisting of a maximum of 65 amino acids. The training process of TopoProGenerator incorporates reinforcement learning and adversarial learning, for fine-tuning. Additionally, it encompasses a stability predictive model trained with a dataset comprising over 200,000 sequences. The results demonstrate that TopoProGenerator is capable of designing stable small protein sequences with specified topology structures. CONCLUSION: TPGen has the ability to generate protein sequences that fold into the specified topology, and the pretraining and fine-tuning methods proposed in this study can serve as a framework for designing various types of proteins.


Asunto(s)
Aminoácidos , Suministros de Energía Eléctrica , Secuencia de Aminoácidos , Lenguaje , Aprendizaje
5.
J Mater Chem B ; 12(5): 1168-1193, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38193143

RESUMEN

A biosensor is a device that reacts with the analyte to be analyzed, detects its concentration, and generates readable information, which plays an important role in medical diagnosis, detection of physiological indicators, and disease prevention. Nanomaterials have received increasing attention in the fabrication and improvement of biosensors due to their unique physicochemical and optical properties. In this paper, the properties of nanomaterials such as the size effect, optical and electrical properties, and their advantages in the field of biosensing are briefly summarized, and the application of nanomaterials can effectively improve the sensitivity and reduce the detection limit of biosensors. The advantages of commonly used nanomaterials such as gold nanoparticles (AuNPs), carbon nanotubes (CNTs), quantum dots (QDs), graphene, and magnetic nanobeads for biosensor applications are also reviewed. Besides, the two main types of biosensors using nanomaterials involved in their construction and their working principles are described, and the toxicity and biocompatibility of nanomaterials and the future direction of nanomaterial biosensors are discussed.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Nanoestructuras , Nanotubos de Carbono , Nanotubos de Carbono/química , Oro/química , Nanopartículas del Metal/química , Nanoestructuras/química
6.
Sci Rep ; 13(1): 16838, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37803169

RESUMEN

The complexity and challenging underwater environment leading to degradation in underwater image. Measuring the quality of underwater image is a significant step for the subsequent image processing step. Existing Image Quality Assessment (IQA) methods do not fully consider the characteristics of degradation in underwater images, which limits their performance in underwater image assessment. To address this problem, an Underwater IQA (UIQA) method based on color space multi-feature fusion is proposed to focus on underwater image. The proposed method converts underwater images from RGB color space to CIELab color space, which has a higher correlation to human subjective perception of underwater visual quality. The proposed method extract histogram features, morphological features, and moment statistics from luminance and color components and concatenate the features to obtain fusion features to better quantify the degradation in underwater image quality. After features extraction, support vector regression(SVR) is employed to learn the relationship between fusion features and image quality scores, and gain the quality prediction model. Experimental results on the SAUD dataset and UIED dataset show that our proposed method can perform well in underwater image quality assessment. The performance comparisons on LIVE dataset, TID2013 dataset,LIVEMD dataset,LIVEC dataset and SIQAD dataset demonstrate the applicability of the proposed method.

7.
Opt Express ; 31(17): 28174-28184, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37710878

RESUMEN

This paper is about the V-cavity tunable semiconductor laser with a 1550 nm band used as a transmitter to build a wavelength division multiplexing (WDM) optical fiber communication link. In the experiment, a 20 km optical fiber communication link with a reasonable eye diagram and low bit error rate (BER) transmitted by 40 Gbps can be established. The experimental results show that a single laser can achieve a wavelength tuning range of 25 nm, reach 32 channels at a 100 GHz frequency interval, and the average side mode suppression ratio (SMSR) is above 39 dB. The advantages and application potential of V-cavity tunable semiconductor laser (VCL) for wavelength routing in optical communication networking are verified by experiments.

8.
PLoS One ; 18(9): e0292000, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37733702

RESUMEN

In this study, a novel rat model of knee joint adhesion was developed, and its formation was analyzed quantitatively over time. Thirty-nine Wistar rats were randomly divided into intact control (n = 3) and experimental (n = 36) groups. The latter was equally divided into three groups according to the experimental intervention: fixed with deep bending of the knee joint (group I), fixed after incision of the capsule (group II), and fixed after exposure of the patellofemoral joint to artificial patellar subluxation (group III). All rats were subdivided according to their joint immobilization period (1, 2, or 4 weeks). Thereafter, the limited range of motion of the knee joint with (limited knee range of motion) and without (limited knee joint intrinsic range of motion) skin and muscles were measured. The lengths of adhesions of the anterior knee joint and posterior capsules were evaluated histologically. The limited intrinsic range of motion of the knee joint was found to be increased in groups II and III compared to that in group I 4 weeks after immobilization. Adhesions were confirmed within 1 week after immobilization in groups II and III. The length of the adhesions in group III was significantly longer than in other groups at 2 weeks and remained longer than in group I at 4 weeks. This model may contribute to the assessment of the adhesion process and development of new therapeutic avenues following trauma or surgical invasion.


Asunto(s)
Articulación de la Rodilla , Articulación Patelofemoral , Ratas , Animales , Ratas Wistar , Adherencias Tisulares , Fenómenos Físicos
9.
Appl Opt ; 62(20): 5580-5587, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37706877

RESUMEN

The paper describes the observation of diverse bound-state patterns, including tightly bound states, loosely bound states, and composite bound states, in a figure-9 fiber laser. By performing dispersion management and using polarization-maintaining fibers with high gain coefficient, stable dispersion-managed solitons and bound solitons can be simultaneously generated. This work advances our understanding of complex soliton dynamics and presents a novel, to the best of our knowledge, approach for future applications of bound states. Additionally, the research involves integrated packaging, effectively enhancing overall work stability.

10.
Appl Environ Microbiol ; 89(9): e0013923, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37668407

RESUMEN

Paenibacillus polymyxa WLY78, a N2-fixing bacterium, has great potential use as a biofertilizer in agriculture. Recently, we have revealed that GlnR positively and negatively regulates the transcription of the nif (nitrogen fixation) operon (nifBHDKENXhesAnifV) in P. polymyxa WLY78 by binding to two loci of the nif promoter according to nitrogen availability. However, the regulatory mechanisms of nitrogen metabolism mediated by GlnR in the Paenibacillus genus remain unclear. In this study, we have revealed that glutamine synthetase (GS) and GlnR in P. polymyxa WLY78 play a key role in the regulation of nitrogen metabolism. P. polymyxa GS (encoded by glnA within glnRA) and GS1 (encoded by glnA1) belong to distinct groups: GSI-α and GSI-ß. Both GS and GS1 have the enzyme activity to convert NH4+ and glutamate into glutamine, but only GS is involved in the repression by GlnR. GlnR represses transcription of glnRA under excess nitrogen, while it activates the expression of glnA1 under nitrogen limitation. GlnR simultaneously activates and represses the expression of amtBglnK and gcvH in response to nitrogen availability. Also, GlnR regulates the expression of nasA, nasD1D2, nasT, glnQHMP, and glnS. IMPORTANCE In this study, we have revealed that Paenibacillus polymyxa GlnR uses multiple mechanisms to regulate nitrogen metabolism. GlnR activates or represses or simultaneously activates and inhibits the transcription of nitrogen metabolism genes in response to nitrogen availability. The multiple regulation mechanisms employed by P. polymyxa GlnR are very different from Bacillus subtilis GlnR which represses nitrogen metabolism under excess nitrogen. Both GS encoded by glnA within the glnRA operon and GS1 encoded by glnA1 in P. polymyxa WLY78 are involved in ammonium assimilation, but only GS is required for regulating GlnR activity. The work not only provides significant insight into understanding the interplay of GlnR and GS in nitrogen metabolism but also provides guidance for improving nitrogen fixation efficiency by modulating nitrogen metabolism.

11.
Foods ; 12(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37444282

RESUMEN

Geographic origins play a vital role in traditional Chinese medicinal materials. Using the geo-authentic crude drug can improve the curative effect. The main producing areas of Chinese wolfberry are Ningxia, Gansu, Qinghai, and so on. The geographic origin of Chinese wolfberry can affect its texture, shape, color, smell, nutrients, etc. However, the traditional method for identifying the geographic origin of Chinese wolfberries is still based on human eyes. To efficiently identify Chinese wolfberries from different origins, this paper presents an intelligent identification method for Chinese wolfberries based on color space transformation and texture morphological features. The first step is to prepare the Chinese wolfberry samples and collect the image data. Then the images are preprocessed, and the texture and morphology features of single wolfberry images are extracted. Finally, the random forest algorithm is employed to establish a model of the geographic origin of Chinese wolfberries. The proposed method can accurately predict the origin information of a single wolfberry image and has the advantages of low cost, fast recognition speed, high recognition accuracy, and no damage to the sample.

12.
Front Optoelectron ; 16(1): 12, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37266731

RESUMEN

This paper proposes a mode-locked fiber laser based on graphene-coated microfiber. The total length of the fiber laser resonant cavity is 31.34 m. Under the condition of stable output of bright-dark soliton pairs from the fiber laser, dual-wavelength tuning is realized by adjusting the polarization controller (PC), and the wavelength tuning range is 11 nm. Furthermore, the effects of polarization states on bright-dark solitons are studied. It is demonstrated that the mode-locking state can be switched between conventional solitons and bright-dark solitons in the graphene mode-locked fiber laser. Bright-dark soliton pairs with different shapes and nanosecond pulse width can be obtained by adjusting the PC and pump power.

13.
Appl Opt ; 62(7): 1667-1671, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37132911

RESUMEN

A cascaded microwave photonic filter refers to a microwave photonic filter (MPF) with higher performance obtained by cascading a MPF with two different structures. A high-Q cascaded single-passband MPF is proposed experimentally based on stimulated Brillouin scattering (SBS) and an optical-electrical feedback loop (OEFL). In this experiment, the pump light of SBS is provided by a tunable laser. The Brillouin gain spectrum generated by the pump light is used to amplify the phase modulation sideband, and the narrow linewidth OEFL is subsequently used to compress the passband width of the MPF. By carefully adjusting the pump wavelength and tuning the tunable optical delay line, stable tuning can be achieved for a cascaded single-passband MPF with a high-Q value. The results have demonstrated that the MPF has characteristics of high-frequency selectivity and a wide frequency tuning range. Meanwhile, the filtering bandwidth is up to 300 kHz, the out-of-band suppression is more than 20 dB, the maximum Q-value is 5.333×104, and the center frequency tuning range is 1-17 GHz. The cascaded MPF proposed not only achieves a higher Q-value, but also has the advantages of tunability, a high out-of-band rejection ratio, and strong cascaded ability.

15.
Environ Sci Pollut Res Int ; 30(19): 56198-56206, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36918487

RESUMEN

Oily sewage discharged from ships has brought many harms to the marine environment, even endangered marine life and human life. As a new type of water treatment technology, microbial fuel cell (MFC) can efficiently treat pollutants and recover energy, which can be converted into electric energy. However, its large internal resistance restricts its development. In order to solve the problems of low power generation performance and poor biocompatibility of microbial fuel cell, a gold nanoparticle-carbon quantum dot/polydopamine/graphene oxide/bacterial cellulose (AuNP-CQD/PDA/GO/BC) electrode was prepared, and it was applied to the treatment of oily sewage from ships. Fourier transforms infrared spectroscopy, X-ray diffraction, scanning electron microscopy, gas chromatography-mass spectrometry, and contact angle measuring instrument were used to characterize the electrode. The results show that PDA bridges GO and AuNP-CQD particles through the electrostatic interaction/π-π bond/hydrogen bonding, respectively. This attracts a large number of microorganisms to attach to the surface of the porous anode material, which greatly improves the activity and quantity of microorganisms. Moreover, the maximum power density of AuNP-CQD/PDA/GO/BC electrode is 2624.91 mW/m2, which obviously improves the electrochemical performance of MFC. The oil content of the treated water is ≤ 15 mg/L, reaching the discharge of MARPOL 73/78 convention. Therefore, the proposed approach has paved new dimensions in not only the preparation of a new composite electrode materials but also its applications as effective degradation of ship oily sewage in MFC.


Asunto(s)
Fuentes de Energía Bioeléctrica , Nanopartículas del Metal , Humanos , Fuentes de Energía Bioeléctrica/microbiología , Aguas del Alcantarillado/microbiología , Navíos , Oro , Electrodos
16.
BMC Genomics ; 24(1): 85, 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36823556

RESUMEN

BACKGROUND: Paenibacillus polymyxa WLY78 is a Gram-positive, endospore-forming and N2-fixing bacterium. Our previous study has demonstrated that GlnR acts as both an activator and a repressor to regulate the transcription of the nif (nitrogen fixation) operon (nifBHDKENXhesAnifV) according to nitrogen availability, which is achieved by binding to the two GlnR-binding sites located in the nif promoter region. However, further study on the GlnR-mediated global regulation in this bacterium is still needed. RESULTS: In this study, global identification of the genes directly under GlnR control is determined by using chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) and electrophoretic mobility shift assays (EMSA). Our results reveal that GlnR directly regulates the transcription of 17 genes/operons, including a nif operon, 14 nitrogen metabolism genes/operons (glnRA, amtBglnK, glnA1, glnK1, glnQHMP, nasA, nasD1, nasD2EF, gcvH, ansZ, pucR, oppABC, appABCDF and dppABC) and 2 carbon metabolism genes (ldh3 and maeA1). Except for the glnRA and nif operon, the other 15 genes/operons are newly identified targets of GlnR. Furthermore, genome-wide transcription analyses reveal that GlnR not only directly regulates the expression of these 17 genes/operons, but also indirectly controls the expression of some other genes/operons involved in nitrogen fixation and the metabolisms of nitrogen and carbon. CONCLUSION: This study provides a GlnR-mediated regulation network of nitrogen fixation and the metabolisms of nitrogen and carbon.


Asunto(s)
Paenibacillus polymyxa , Paenibacillus polymyxa/genética , Paenibacillus polymyxa/metabolismo , Nitrógeno/metabolismo , Regiones Promotoras Genéticas , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Regulación Bacteriana de la Expresión Génica
17.
Environ Toxicol Pharmacol ; 97: 104035, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36496184

RESUMEN

OBJECTIVES: To evaluate the risk of cognitive impairment in workers with plasma aluminum concentrations and lifestyles using a Bayesian network (BN). METHODS: In 2019, 476 male workers in the Shanxi Aluminum factory were investigated. We measured plasma aluminum concentrations in workers by inductive coupled plasma mass spectrometry (ICPMS) and tested workers' cognitive function by the MoCA scale. We collected the data of lifestyle by the occupational Workers' Health questionnaire and express the influence of lifestyle on cognition by the OR value (95 %CI) of logistic regression. A Bayesian network model was used to predict the risk of cognitive dysfunction. RESULTS: The subjects were divided into a cognitively normal group and cognitively impaired group according to MoCA scores. There were statistically significant differences in age, education level, alcohol consumption, physical exercise, reading, aluminum length of service and blood aluminum concentration between the two groups (P < 0.05). The plasma aluminum concentration in the cognitive impairment group was 1.68 times higher than that in the cognitive normal group. Four groups were established according to the quartile of blood aluminum concentration of the subjects, namely, Group Q1 (<14.95 µg/L), Q2 group (14.95-32.96 µg/L), Q3 group (32.96-56.62 µg/L), and Q4 group (>56.62 µg/L). Binary logistic regression analysis showed that in the adjustment variable Model2, drinking, short sleep, long sleep, and mobile phone use increased the risk of cognitive impairment by 1.505(0.99,2.289), 1.269(0.702,2.295), 1.125(0.711,1.781) and 1.19(0.779,1.82), respectively, compared with their reference values. The risk of cognitive impairment from reading and exercise was 0.7(0.398,1.232) and 0.787(0.51,1.217), respectively, compared with those of no reading and no exercise. The risk of cognitive impairment of blood aluminum concentration in the Q2, Q3, and Q4 groups was 2.103(1.092,4.051), 1.866(0.955,3.644) and 3.679(1.928,7.020), respectively, compared with that in the Q1 group. Compared with age <40 , the risk of cognitive impairment of age ≥40 was 2.515(1.508,4.193) (P < 0.05). Bayesian network model results showed that if all participants had plasma aluminum concentrations higher than Q4, the prevalence of cognitive impairment was 54.5 %. The prevalence of cognitive impairment was 75.0 % if all participants had plasma aluminum levels above Q4, were older than 40, smoked, drank alcohol, used a cell phone for more than 2 h, slept for more than 8 h, did not exercise, and did not read. CONCLUSIONS: Our findings suggest that both poor lifestyle and occupational aluminum exposure may affect cognitive function. Workers must maintain a reasonable lifestyle and reduce aluminum exposure, which can control the occurrence of cognitive impairment.


Asunto(s)
Disfunción Cognitiva , Exposición Profesional , Humanos , Masculino , Aluminio/toxicidad , Teorema de Bayes , Cromatografía de Gases y Espectrometría de Masas , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/epidemiología , Cognición , Exposición Profesional/efectos adversos , Estilo de Vida
18.
Front Genet ; 14: 1347667, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38274106

RESUMEN

Introduction: Protein engineering, which aims to improve the properties and functions of proteins, holds great research significance and application value. However, current models that predict the effects of amino acid substitutions often perform poorly when evaluated for precision. Recent research has shown that ProteinMPNN, a large-scale pre-training sequence design model based on protein structure, performs exceptionally well. It is capable of designing mutants with structures similar to the original protein. When applied to the field of protein engineering, the diverse designs for mutation positions generated by this model can be viewed as a more precise mutation range. Methods: We collected three biological experimental datasets and compared the design results of ProteinMPNN for wild-type proteins with the experimental datasets to verify the ability of ProteinMPNN in improving protein fitness. Results: The validation on biological experimental datasets shows that ProteinMPNN has the ability to design mutation types with higher fitness in single and multi-point mutations. We have verified the high accuracy of ProteinMPNN in protein engineering tasks from both positive and negative perspectives. Discussion: Our research indicates that using large-scale pre trained models to design protein mutants provides a new approach for protein engineering, providing strong support for guiding biological experiments and applications in biotechnology.

19.
Cell Rep ; 41(10): 111737, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36476878

RESUMEN

Mammalian teeth develop from the inductive epithelial-mesenchymal interaction, an important mechanism shared by many organs. The cellular basis for such interaction remains elusive. Here, we generate a dual-fluorescence model to track and analyze dental cells from embryonic to postnatal stages, in which Pitx2+ epithelium and Msx1+ mesenchyme are sufficient for tooth reconstitution. Single-cell RNA sequencing and spatial mapping further revealed critical cellular dynamics during molar development, where tooth germs are organized by Msx1+Sdc1+ dental papilla and surrounding dental niche. Surprisingly, niche cells are more efficient in tooth reconstitution and can directly regenerate papilla cells through interaction with dental epithelium. Finally, from the dental niche, we identify a group of previously unappreciated migratory Msx1+ Sox9+ cells as the potential cell origin for dental papilla. Our results indicate that the dental niche cells directly contribute to tooth organogenesis and provide critical insights into the essential cell composition for tooth engineering.


Asunto(s)
Diente , Diente/crecimiento & desarrollo
20.
Front Microbiol ; 13: 993214, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36274703

RESUMEN

The enrichment of soil-borne fungal pathogens and a high input of mineral fertilizer in the continuous cropping of cereal crops have raised a concern about soil health deterioration. Conversion of continuous cereal cropping to a legume-involved system alters the soil fungal community. However, when a leguminous cover crop is grown with a succeeding legume grain crop such as soya (Glycine max L. Merril), the effects on the soil fungal community when two legumes are involved in the crop system remain unclear. Thus, the effects of the cover crop on the soil fungal community under a succession of soya and a succession of maize (Zea mays L.) were clarified: a continuous wheat (Triticum aestivum L.)-maize cropping system was converted to new rotation systems with three cover crop treatments: leguminous vetch (Vicia sativa L.), a mixture of vetch and rye (Secale cereale L.), and fallow, succeeded by soya or maize in this study. The soil fungal community at the harvest of soya and maize were determined using high-throughput sequencing of ITS2 amplicons. Compared to a wheat-maize rotation system, all of the new rotation systems that involved leguminous crops or fallow increased the soil fungal diversity and suppressed pathotrophs by reducing the soil NH4 +, NO3 -, available K, and available P concentrations. Different cover crops changed the fungal community composition, but their effect was overwhelmed by the strong effect of succeeding soya, which induced minor shifts among the cover crop treatments under soya than maize. The Vetch-Soya system exhibited the highest fungal diversity, which have been due to an increase of symbiotrophs. Replacing wheat with mixed vetch and rye most greatly suppressed the pathotrophs, and this suppression effect was stronger when succeeded by maize than by soya. These results showed the short-term benefits of legume-legume succession and legume-cereal mixed cover crops for increasing fungal diversity and suppressing pathotrophs. Further study is needed to examine the long-term effects of Vetch-Soya on the accumulation of legume-associated pathogens.

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