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1.
Brief Bioinform ; 24(6)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37870286

RESUMO

The advanced language models have enabled us to recognize protein-protein interactions (PPIs) and interaction sites using protein sequences or structures. Here, we trained the MindSpore ProteinBERT (MP-BERT) model, a Bidirectional Encoder Representation from Transformers, using protein pairs as inputs, making it suitable for identifying PPIs and their respective interaction sites. The pretrained model (MP-BERT) was fine-tuned as MPB-PPI (MP-BERT on PPI) and demonstrated its superiority over the state-of-the-art models on diverse benchmark datasets for predicting PPIs. Moreover, the model's capability to recognize PPIs among various organisms was evaluated on multiple organisms. An amalgamated organism model was designed, exhibiting a high level of generalization across the majority of organisms and attaining an accuracy of 92.65%. The model was also customized to predict interaction site propensity by fine-tuning it with PPI site data as MPB-PPISP. Our method facilitates the prediction of both PPIs and their interaction sites, thereby illustrating the potency of transfer learning in dealing with the protein pair task.


Assuntos
Aprendizado de Máquina , Proteínas , Proteínas/química , Sequência de Aminoácidos
2.
J Am Chem Soc ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728652

RESUMO

Porous organic polymers (POPs) with inherent porosity, tunable pore environment, and semiconductive property are ideally suitable for application in various advanced semiconductor-related devices. However, owing to the lack of processability, POPs are usually prepared in powder forms, which limits their application in advanced devices. Herein, we demonstrate an example of information storage application of POPs with film form prepared by an electrochemical method. The growth process of the electropolymerized films in accordance with the Volmer-Weber model was proposed by observation of atomic force microscopy. Given the mechanism of the electron transfer system, we verified and mainly emphasized the importance of porosity and interfacial properties of porous polymer films for memristor. As expected, the as-fabricated memristors exhibit good performance on low turn-on voltage (0.65 ± 0.10 V), reliable data storage, and high on/off current ratio (104). This work offers inspiration for applying POPs in the form of electropolymerized films in various advanced semiconductor-related devices.

3.
Appl Environ Microbiol ; : e0208223, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899886

RESUMO

Genetic engineering at the genomic scale provides a rapid means to evolve microbes for desirable traits. However, in many filamentous fungi, such trials are daunted by low transformation efficiency. Differentially expressed genes under certain conditions may contain important regulatory factors. Accordingly, although manipulating these subsets of genes only can largely reduce the time and labor, engineering at such a sub-genomic level may also be able to improve the microbial performance. Herein, first using the industrially important cellulase-producing filamentous fungus Trichoderma reesei as a model organism, we constructed suppression subtractive hybridization (SSH) libraries enriched with differentially expressed genes under cellulase induction (MM-Avicel) and cellulase repression conditions (MM-Glucose). The libraries, in combination with RNA interference, enabled sub-genomic engineering of T. reesei for enhanced cellulase production. The ability of T. reesei to produce endoglucanase was improved by 2.8~3.3-fold. In addition, novel regulatory genes (tre49304, tre120391, and tre123541) were identified to affect cellulase expression in T. reesei. Iterative manipulation using the same strategy further increased the yield of endoglucanase activity to 75.6 U/mL, which was seven times as high as that of the wild type (10.8 U/mL). Moreover, using Humicola insolens as an example, such a sub-genomic RNAi-assisted strain evolution proved to be also useful in other industrially important filamentous fungi. H. insolens is a filamentous fungus commonly used to produce catalase, albeit with similarly low transformation efficiency and scarce knowledge underlying the regulation of catalase expression. By combining SSH and RNAi, a strain of H. insolens producing 28,500 ± 288 U/mL of catalase was obtained, which was 1.9 times as high as that of the parent strain.IMPORTANCEGenetic engineering at the genomic scale provides an unparalleled advantage in microbial strain improvement, which has previously been limited only to the organisms with high transformation efficiency such as Saccharomyces cerevisiae and Escherichia coli. Herein, using the filamentous fungus Trichoderma reesei as a model organism, we demonstrated that the advantage of suppression subtractive hybridization (SSH) to enrich differentially expressed genes and the convenience of RNA interference to manipulate a multitude of genes could be combined to overcome the inadequate transformation efficiency. With this sub-genomic evolution strategy, T. reesei could be iteratively engineered for higher cellulase production. Intriguingly, Humicola insolens, a fungus with even little knowledge in gene expression regulation, was also improved for catalase production. The same strategy may also be expanded to engineering other microorganisms for enhanced production of proteins, organic acids, and secondary metabolites.

4.
Environ Sci Technol ; 58(13): 5821-5831, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38416534

RESUMO

Microplastics (MPs) contamination presents a significant global environmental challenge, with its potential to influence soil carbon (C) dynamics being a crucial aspect for understanding soil C changes and global C cycling. This meta-analysis synthesizes data from 110 peer-reviewed publications to elucidate the directional, magnitude, and driving effects of MPs exposure on soil C dynamics globally. We evaluated the impacts of MPs characteristics (including type, biodegradability, size, and concentration), soil properties (initial pH and soil organic C [SOC]), and experimental conditions (such as duration and plant presence) on various soil C components. Key findings included the significant promotion of SOC, dissolved organic C, microbial biomass C, and root biomass following MPs addition to soils, while the net photosynthetic rate was reduced. No significant effects were observed on soil respiration and shoot biomass. The study highlights that the MPs concentration, along with other MPs properties and soil attributes, critically influences soil C responses. Our results demonstrate that both the nature of MPs and the soil environment interact to shape the effects on soil C cycling, providing comprehensive insights and guiding strategies for mitigating the environmental impact of MPs.


Assuntos
Plásticos , Solo , Microplásticos , Fotossíntese , Carbono , Ecossistema
5.
Appl Microbiol Biotechnol ; 108(1): 13, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38170309

RESUMO

The cellulose-rich corncob residue (CCR) is an abundant and renewable agricultural biomass that has been under-exploited. In this study, two strategies were compared for their ability to transform CCR into cello-oligosaccharides (COS). The first strategy employed the use of endo-glucanases. Although selected endo-glucanases from GH9, GH12, GH45, and GH131 could release COS with degrees of polymerization from 2 to 4, the degrading efficiency was low. For the second strategy, first, CCR was efficiently depolymerized to glucose and cellobiose using the cellulase from Trichoderma reesei. Then, using these simple sugars and sucrose as the starting materials, phosphorylases from different microorganisms were combined to generate COS to a level up to 100.3 g/L with different patterns and degrees of polymerization. Using tomato as a model plant, the representative COS obtained from BaSP (a sucrose phosphorylase from Bifidobacterium adolescens), CuCbP (a cellobiose phosphorylase from Cellulomonas uda), and CcCdP (a cellodextrin phosphorylase from Clostridium cellulosi) were shown to be able to promote plant growth. The current study pointed to an approach to make use of CCR for production of the value-added COS. KEY POINTS: • Sequential use of cellulase and phosphorylases effectively generated cello-oligosaccharides from corncob residue. • Cello-oligosaccharides patterns varied in accordance to cellobiose/cellodextrin phosphorylases. • Spraying cello-oligosaccharides promoted tomato growth.


Assuntos
Celobiose , Celulase , Zea mays , Oligossacarídeos/química , Fosforilases
6.
J Med Genet ; 60(12): 1210-1214, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37468236

RESUMO

To date, over 200 families with hereditary leiomyomatosis and renal cell carcinoma (HLRCC) and over 600 families with Birt-Hogg-Dubé (BHD) syndrome have been reported, with low incidence. Here, we describe a patient with suspected rare HLRCC complicated by BHD syndrome. The proband (II1) had characteristic cutaneous leiomyoma-like protrusions on the neck and back, a left renal mass and multiple right renal, liver and bilateral lung cysts. Three family members (I1, II2, II3) had a history of renal cancer and several of the aforementioned clinical features. Two family members (II1, II3) diagnosed with fumarate hydratase (FH)-deficient papillary RCC via pathological biopsy carried two heterozygous variants: FH (NM_000143.3) missense mutation c.1189G>A (p.Gly397Arg) and FLCN (NM_144997.5) frameshift mutation c.1579_1580insA (p.Arg527Glnfs*75). No family member carrying a single variant had renal tumours. In HEK293T cells transfected with mutant vectors, mRNA and protein expression after FLCN p.Arg527Glnfs*75 and FH p.Gly397Arg mutations were significantly lower than those in wild-type (WT) cells. Cell immunofluorescence showed altered protein localisation and reduced protein expression after FLCN p.Arg527Glnfs*75 mutation. The FH WT was uniformly distributed in the cytoplasm, whereas FH protein expression was reduced after the p.Gly397Arg mutation and scattered sporadically with altered cell localisation. Patients with two variants may have a significantly increased penetrance of RCC.


Assuntos
Síndrome de Birt-Hogg-Dubé , Carcinoma de Células Renais , Neoplasias Renais , Leiomiomatose , Humanos , Síndrome de Birt-Hogg-Dubé/complicações , Síndrome de Birt-Hogg-Dubé/genética , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/genética , Células HEK293 , Neoplasias Renais/complicações , Neoplasias Renais/genética , Leiomiomatose/complicações , Leiomiomatose/genética , Fenótipo
7.
Ecotoxicol Environ Saf ; 272: 116049, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38301584

RESUMO

Global concern exists regarding the contamination of food and animal feed with aflatoxin B1 (AFB1), which poses a threat to the health of both humans and animals. Previously, we found that a laccase from Bacillus subtilis (BsCotA) effectively detoxified AFB1 in a reaction mediated by methyl syringate (MS), although the underlying mechanism has not been determined. Therefore, our primary objective of this study was to explore the detoxification mechanism employed by BsCotA. First, the enzyme and mediator dependence of AFB1 transformation were studied using the BsCotA-MS system, which revealed the importance of MS radical formation during the oxidation process. Aflatoxin Q1 (AFQ1) resulting from the direct oxidation of AFB1 by BsCotA, was identified using ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results of UPLC-MS/MS and density functional theory calculations indicated that the products included AFQ1, AFB1-, and AFD1-MS-coupled products in the BsCotA-MS system. The toxicity evaluations revealed that the substances derived from the transformation of AFB1 through the BsCotA-MS mechanism exhibited markedly reduced toxicity compared to AFB1. Finally, we proposed a set of different AFB1-transformation pathways generated by the BsCotA-MS system based on the identified products. These findings greatly enhance the understanding of the AFB1-transformation mechanism of the laccase-mediator system.


Assuntos
Aflatoxina B1 , Ácido Gálico/análogos & derivados , Lacase , Humanos , Aflatoxina B1/toxicidade , Aflatoxina B1/química , Cromatografia Líquida , Espectrometria de Massas em Tandem
8.
Sensors (Basel) ; 24(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38257581

RESUMO

In this study, a portable spectral analysis instrument based on spontaneous emission spectroscopy (SES) was developed for the in situ, non-intrusive, and quantitative measurement of gaseous Na inside ZD coal-fired boilers, which is mainly applied for predicting slagging in furnaces. This technology is needed urgently because the problem of fouling and slagging caused by high alkali metals in ZD coal restricts the rational utilization of this coal. The relative extended uncertainty for the measurement of gaseous Na concentration is Urel = 10%, k = 2, which indicates that measurement data are reliable under working conditions. It was found that there is a clear linear relationship between the concentration of gaseous Na and fouling in high-alkali coal boilers. Therefore, a fast and efficient method for predicting the slagging and fouling of high-alkali coal boilers can be established by using this in situ online real-time optical measurement.

9.
Small ; 19(16): e2206868, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36710247

RESUMO

Wearable glucose sensors are of great significance and highly required in mobile health monitoring and management but suffering from limited long-term stability and wearable adaptability. Here a simultaneous component and structure engineering strategy is presented, which involves Pt with abundant Ni to achieve three-dimensional, dual-structural Pt-Ni hydrogels with interconnected networks of PtNi nanowires and Ni(OH)2 nanosheets, showing prominent electrocatalytic activity and stability in glucose oxidation under neutral condition. Specifically, the PtNi(1:3) dual hydrogels shows 2.0 and 270.6 times' activity in the glucose electro-oxidation as much as the pure Pt and Ni hydrogels. Thanks to the high activity, structural stability, good flexibility, and self-healing property, the PtNi(1:3) dual gel-based non-enzymatic glucose sensing chip is endowed with high performance. It features a high sensitivity, an excellent selectivity and flexibility, and particularly an outstanding long-term stability over 2 months. Together with a pH sensor and a wireless circuit, an accurate, real-time, and remote monitoring of sweat glucose is achieved. This facile design of novel dual-structural metallic hydrogels sheds light to rationally develop new functional materials for high-performance wearable biosensors.


Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Glucose/química , Níquel/química , Platina/química , Hidrogéis , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos
10.
Am J Pathol ; 192(10): 1433-1447, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948079

RESUMO

Costimulatory molecules are an indispensable signal for activating immune cells. However, the features of many costimulatory molecule genes (CMGs) in lung adenocarcinoma (LUAD) are poorly understood. This study systematically explored expression patterns of CMGs in the tumor immune microenvironment (TIME) status of patients with LUAD. Their expression profiles were downloaded from The Cancer Genome Atlas and the Gene Expression Omnibus databases. Two robust TIME subtypes ("hot" and "cold") were classified by K-means clustering and estimation of stromal and immune cells in malignant tumor tissues using expression data. The "hot" subtype presented higher infiltration in activated immune cells and enrichments in the immune cell receptor signaling pathway and adaptive immune response. Three CMGs (CD80, LTB, and TNFSF8) were screened as final diagnostic markers by means of Least Absolute Shrinkage Selection Operator and Support Vector Machine-Recursive Feature Elimination algorithms. Accordingly, the diagnostic nomogram for predicting individualized TIME status showed satisfactory diagnostic accuracy in The Cancer Genome Atlas training cohort as well as GSE31210 and GSE180347 validation cohorts. Immunohistochemistry staining of 16 specimens revealed an apparently positive correlation between the expression of CMG biomarkers and pathologic response to immunotherapy. Thus, this diagnostic nomogram provided individualized predictions in TIME status of LUAD patients with good predictive accuracy, which could serve as a potential tool for identifying ideal candidates for immunotherapy.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Algoritmos , Biologia Computacional , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Aprendizado de Máquina , Prognóstico , Microambiente Tumoral/genética
11.
Appl Environ Microbiol ; 89(3): e0210722, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36912653

RESUMO

Copper (Cu) homeostasis has not been well documented in filamentous fungi, especially extremophiles. One of the main obstacles impeding their characterization is the lack of a powerful genome-editing tool. In this study, we applied a CRISPR/Cas9 system for efficient targeted gene disruption in the acidophilic fungus Acidomyces richmondensis MEY-1, formerly known as Bispora sp. strain MEY-1. Using this system, we investigated the basis of Cu tolerance in strain MEY-1. This strain has extremely high Cu tolerance among filamentous fungi, and the transcription factor ArAceA (A. richmondensis AceA) has been shown to be involved in this process. The ArAceA deletion mutant (ΔArAceA) exhibits specific growth defects at Cu concentrations of ≥10 mM and is transcriptionally more sensitive to Cu than the wild-type strain. In addition, the putative metallothionein ArCrdA was involved in Cu tolerance only under high Cu concentrations. MEY-1 has no Aspergillus nidulans CrpA homologs, which are targets of AceA-like transcription factors and play a role in Cu tolerance. Instead, we identified the Cu-transporting P-type ATPase ArYgA, homologous to A. nidulans YgA, which was involved in pigmentation rather than Cu tolerance. When the ΔArYgA mutant was grown on medium supplemented with Cu ions, the black color was completely restored. The lack of CrpA homologs in A. richmondensis MEY-1 and its high tolerance to Cu suggest that a novel Cu detoxification mechanism differing from the AceA-CrpA axis exists. IMPORTANCE Filamentous fungi are widely distributed worldwide and play an important ecological role as decomposers. However, the mechanisms of their adaptability to various environments are not fully understood. Various extremely acidophilic filamentous fungi have been isolated from acidic mine drainage (AMD) with extremely low pH and high heavy metal and sulfate concentrations, including A. richmondensis. The lack of genetic engineering tools, particularly genome-editing tools, hinders the study of these acidophilic and heavy metal-resistant fungi at the molecular level. Here, we first applied a CRISPR/Cas9-mediated gene-editing system to A. richmondensis MEY-1. Using this system, we identified and characterized the determinants of Cu resistance in A. richmondensis MEY-1. The conserved roles of the Cu-binding transcription factor ArAceA in Cu tolerance and the Cu-transporting P-type ATPase ArYgA in the Cu-dependent production of pigment were confirmed. Our findings provide insights into the molecular basis of Cu tolerance in the acidophilic fungus A. richmondensis MEY-1. Furthermore, the CRISPR/Cas9 system used here would be a powerful tool for studies of the mechanisms of adaptability of acidophilic fungi to extreme environments.


Assuntos
Ascomicetos , ATPases do Tipo-P , Cobre/farmacologia , Cobre/metabolismo , Sistemas CRISPR-Cas , Edição de Genes , Ascomicetos/genética , Ascomicetos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , ATPases do Tipo-P/genética
12.
Crit Rev Biotechnol ; 43(5): 698-715, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35723581

RESUMO

The regulation and prohibition of antibiotics used as growth promoters (AGP) in the feed field are increasing because they cause antimicrobial resistance and drug residue issues and threaten community health. Recently, glucose oxidase (GOx) has attracted increasing interest in the feed industry as an alternative to antibiotics. GOx specifically catalyzes the production of gluconic acid (GA) and hydrogen peroxide (H2O2) by consuming molecular oxygen, and plays an important role in relieving oxidative stress, preserving health, and promoting animal growth. To expand the application of GOx in the feed field, considerable efforts have been made to mine new genetic resources. Efforts have also been made to heterologously overexpress relevant genes to reduce production costs and to engineer proteins by modifying enzyme properties, both of which are bottleneck problems that limit industrial feed applications. Herein, the: different sources, diverse biochemical properties, distinct structural features, and various strategies of GOx engineering and heterologous overexpression are summarized. The mechanism through which GOx promotes growth in animal production, including the improvement of antioxidant capacity, maintenance of intestinal microbiota homeostasis, and enhancement of gut function, are also systematically addressed. Finally, a new perspective is provided for the future development of GOx applications in the feed field.


Assuntos
Glucose Oxidase , Peróxido de Hidrogênio , Animais , Glucose Oxidase/genética , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Antibacterianos , Glucose/metabolismo
13.
Microb Cell Fact ; 22(1): 59, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36978060

RESUMO

BACKGROUND: Heme proteins, such as hemoglobin, horseradish peroxidase and cytochrome P450 (CYP) enzyme, are highly versatile and have widespread applications in the fields of food, healthcare, medical and biological analysis. As a cofactor, heme availability plays a pivotal role in proper folding and function of heme proteins. However, the functional production of heme proteins is usually challenging mainly due to the insufficient supply of intracellular heme. RESULTS: Here, a versatile high-heme-producing Escherichia coli chassis was constructed for the efficient production of various high-value heme proteins. Initially, a heme-producing Komagataella phaffii strain was developed by reinforcing the C4 pathway-based heme synthetic route. Nevertheless, the analytical results revealed that most of the red compounds generated by the engineered K. phaffii strain were intermediates of heme synthesis which were unable to activate heme proteins. Subsequently, E. coli strain was selected as the host to develop heme-producing chassis. To fine-tune the C5 pathway-based heme synthetic route in E. coli, fifty-two recombinant strains harboring different combinations of heme synthesis genes were constructed. A high-heme-producing mutant Ec-M13 was obtained with negligible accumulation of intermediates. Then, the functional expression of three types of heme proteins including one dye-decolorizing peroxidase (Dyp), six oxygen-transport proteins (hemoglobin, myoglobin and leghemoglobin) and three CYP153A subfamily CYP enzymes was evaluated in Ec-M13. As expected, the assembly efficiencies of heme-bound Dyp and oxygen-transport proteins expressed in Ec-M13 were increased by 42.3-107.0% compared to those expressed in wild-type strain. The activities of Dyp and CYP enzymes were also significantly improved when expressed in Ec-M13. Finally, the whole-cell biocatalysts harboring three CYP enzymes were employed for nonanedioic acid production. High supply of intracellular heme could enhance the nonanedioic acid production by 1.8- to 6.5-fold. CONCLUSION: High intracellular heme production was achieved in engineered E. coli without significant accumulation of heme synthesis intermediates. Functional expression of Dyp, hemoglobin, myoglobin, leghemoglobin and CYP enzymes was confirmed. Enhanced assembly efficiencies and activities of these heme proteins were observed. This work provides valuable guidance for constructing high-heme-producing cell factories. The developed mutant Ec-M13 could be employed as a versatile platform for the functional production of difficult-to-express heme proteins.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Mioglobina/metabolismo , Leghemoglobina/metabolismo , Proteínas de Transporte , Heme/metabolismo , Oxigênio/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo
14.
Microb Cell Fact ; 22(1): 236, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974259

RESUMO

BACKGROUND: Thermophilic fungus Myceliophthora thermophila has been widely used in industrial applications due to its ability to produce various enzymes. However, the lack of an efficient protein expression system has limited its biotechnological applications. RESULTS: In this study, using a laccase gene reporting system, we developed an efficient protein expression system in M. thermophila through the selection of strong constitutive promoters, 5'UTRs and signal peptides. The expression of the laccase was confirmed by enzyme activity assays. The results showed that the Mtpdc promoter (Ppdc) was able to drive high-level expression of the target protein in M. thermophila. Manipulation of the 5'UTR also has significant effects on protein expression and secretion. The best 5'UTR (NCA-7d) was identified. The transformant containing the laccase gene under the Mtpdc promoter, NCA-7d 5'UTR and its own signal peptide with the highest laccase activity (1708 U/L) was obtained. In addition, the expression system was stable and could be used for the production of various proteins, including homologous proteins like MtCbh-1, MtGh5-1, MtLPMO9B, and MtEpl1, as well as a glucoamylase from Trichoderma reesei. CONCLUSIONS: An efficient protein expression system was established in M. thermophila for the production of various proteins. This study provides a valuable tool for protein production in M. thermophila and expands its potential for biotechnological applications.


Assuntos
Lacase , Sordariales , Lacase/genética , Lacase/metabolismo , Regiões 5' não Traduzidas/genética , Regiões Promotoras Genéticas , Sordariales/genética , Sordariales/metabolismo
15.
J Org Chem ; 88(13): 8791-8801, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37260330

RESUMO

A [6 + 1] annulation reaction via cascade 1,6-hydride transfer/cyclization is reported to construct a polycyclic 3,4-fused azepinoindole skeleton. The newly designed 4-amino-indole-3-carbaldehyde is applied as a novel six-atom synthon, interacting with arylamines and malononitrile to achieve the [6 + 1] annulation. Notably, the reaction proceeds smoothly under redox-neutral and metal-free conditions, providing a wide range of azepinoindoles in up to 94% yields, with water as the only byproduct. Besides, the advantage of high step- and atom-economy further highlights the practicality of this methodology.


Assuntos
Paládio , Catálise , Ciclização , Oxirredução
16.
Helicobacter ; 28(5): e13012, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37515414

RESUMO

BACKGROUND: Vonoprazan is an emerging option for the treatment of Helicobacter pylori infection. We aimed to assess the research trends and hotspots of vonoprazan-based therapy for H. pylori eradication through bibliometric analysis. MATERIALS AND METHODS: Vonoprazan-based studies for eradicating H. pylori published from 2015 to 2023 were extracted from the Web of Science using a combination of the search terms "H. pylori" and "vonoprazan." Each study was weighted according to the number of included patients. RESULTS: A total of 65 studies were included. Japan was the most productive and cooperative country, accounting for 69.2% of publications. Vonoprazan in combination with amoxicillin and clarithromycin (41.8%) was most used for eradicating H. pylori, followed by vonoprazan in combination with amoxicillin (20.4%) and vonoprazan in combination with amoxicillin and metronidazole (19.4%). The eradication rates for first-line vonoprazan-based therapies by intention to treat were: dual therapy (82.9%, 95% CI: 77.7%-88.0%), triple (83.3%, 95% CI: 79.7%-86.8%) and quadruple therapy (91.5%, 95% CI: 85.5%-97.4%), and per protocol: dual therapy (86.1%, 95% CI: 81.5%-90.7%), triple (89.3%, 95% CI: 87.9%-90.6%) and quadruple therapy (94.0%, 95% CI: 88.6%-99.4%). Vonoprazan was superior to proton pump inhibitors in triple therapy regarding empirical therapy (RR = 1.18, 95% CI, 1.14-1.22, p < 0.01) and clarithromycin-resistant group (RR = 1.71, 95% CI, 1.33-2.20, p < 0.01), but there is no significant difference between triple therapy and dual therapy (RR = 1.02, 95% CI, 0.98-1.07, p = 0.33). CONCLUSIONS: Vonoprazan has been widely used for H. pylori eradication. Further studies are needed to optimize the best duration and dosage of vonoprazan-based regimens in different regions.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Claritromicina/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Antibacterianos/uso terapêutico , Quimioterapia Combinada , Amoxicilina/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico , Resultado do Tratamento
17.
Org Biomol Chem ; 21(4): 700-714, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36601772

RESUMO

The use of alkyl amines and ethers as traceless hydride donors in [1,5]-hydride transfer cascade reactions represents a promising strategy that greatly enriches redox-neutral hydride transfer chemistry. This review summarizes the remarkable progress made in this field, and focuses on (1) alkyl amines as traceless hydride donors in cascade [1,5]-hydride transfer/elimination reactions and (2) alkyl ethers as traceless hydride donors in [1,5]-hydride transfer cascade reactions. The reaction mechanisms, features, scope, limitations, and synthetic applications are included, where appropriate. Importantly, its powerful ability in allene synthesis and the combination with [Re]-vinylidene and carbocation chemistries render this strategy attractive enough to inspire chemists to develop colorful reactions for building molecular complexity.

18.
BMC Endocr Disord ; 23(1): 141, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37415163

RESUMO

BACKGROUND: As an invasive technique, selective venous sampling (SVS) is considered a useful method to identify a lesion's location to increase the success rate of secondary surgery in patients with primary hyperparathyroidism (pHPT) caused by ectopic parathyroid adenomas. CASE PRESENTATION: We present a case of post-surgical persistent hypercalcemia and elevated parathyroid hormone (PTH) levels in a 44-year-old woman with previously undetected parathyroid adenoma. An SVS was then performed for further localization of the adenoma, as other non-invasive methods showed negative results. After SVS, an ectopic adenoma was suspected in the sheath of the left carotid artery, previously considered as a schwannoma, and was pathologically confirmed after the second operation. Postoperatively, the patient's symptoms disappeared and serum levels of PTH and calcium normalized. CONCLUSIONS: SVS can provide precise diagnosis and accurate positioning before re-operation in patients with pHPT.


Assuntos
Adenoma , Hiperparatireoidismo Primário , Neoplasias das Paratireoides , Feminino , Humanos , Adulto , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/diagnóstico , Glândulas Paratireoides/cirurgia , Neoplasias das Paratireoides/complicações , Neoplasias das Paratireoides/diagnóstico , Neoplasias das Paratireoides/cirurgia , Cálcio , Adenoma/complicações , Adenoma/diagnóstico , Adenoma/cirurgia , Hormônio Paratireóideo
19.
Environ Res ; 224: 115447, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36758919

RESUMO

A green, high-efficiency, and wide pH tolerance water remediation process has been urgently acquired for the increasingly exacerbating contaminated water. In this study, a Fe3+/persulfate (Fe3+/PS) system was employed and enhanced with a green natural ligand cysteine (Cys) for the degradation of quinclorac (QNC). The introduction of Cys into the Fe3+/PS system widened the effective pH range to 9 with a superior removal rate for QNC. The mechanism revealed that the Fe3+/Cys/PS system can enhance the ability of degrading QNC by accelerating the Fe3+/Fe2+ redox cycle, maintaining Fe2+ concentration and thereby generating more HO• and SO4•-. The impact factors (i.e., pH, concentrations of PS, Fe3+ and Cys) were optimized as well. This work provides a promising strategy with high catalytic activity and wide pH tolerance for organic contaminated water remediation.


Assuntos
Quinolinas , Poluentes Químicos da Água , Purificação da Água , Cisteína/química , Concentração de Íons de Hidrogênio , Oxirredução , Água , Poluentes Químicos da Água/análise , Química Verde
20.
Appl Microbiol Biotechnol ; 107(14): 4543-4551, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37261455

RESUMO

Insulin-like growth factor-1 (IGF-1) is a pleiotropic protein hormone and has become an attractive therapeutic target because of its multiple roles in various physiological processes, including growth, development, and metabolism. However, its production is hindered by low heterogenous protein expression levels in various expression systems and hard to meet the needs of clinical and scientific research. Here, we report that human IGF-1 and its analog Long R3 IGF-1 (LR3 IGF-1) are recombinant expressed and produced in the Pichia pastoris (P. pastoris) expression system through being fused with highly expressed xylanase XynCDBFV. Furthermore, purified IGF-1 and LR3 IGF-1 display excellent bioactivity of cell proliferation compared to the standard IGF-1. Moreover, higher heterologous expression levels of the fusion proteins XynCDBFV-IGF-1 and XynCDBFV-LR3 IGF-1 are achieved by fermentation in a 15-L bioreactor, reaching up to about 0.5 g/L XynCDBFV-IGF-1 and 1 g/L XynCDBFV-TEV-LR3 IGF-1. Taken together, high recombinant expression of bioactive IGF-1 and LR3 IGF-1 is acquired with the assistance of xylanase as a fusion partner in P. pastoris, which could be used for both clinical and scientific applications. KEY POINTS: • Human IGF-1 and LR3 IGF-1 are produced in the P. pastoris expression system. • Purified IGF-1 and LR3 IGF-1 show bioactivity comparable to the standard IGF-1. • High heterologous expression of IGF-1 and LR3 IGF-1 is achieved by fermentation in a bioreactor.


Assuntos
Fator de Crescimento Insulin-Like I , Saccharomycetales , Humanos , Proteínas Recombinantes/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Pichia/genética , Pichia/metabolismo , Saccharomycetales/metabolismo
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