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1.
Microbiol Res ; 283: 127712, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593580

RESUMO

Lipid A plays a crucial role in Vibrio parahaemolyticus. Previously we have reported the diversity of secondary acylation of lipid A in V. parahaemolyticus and four V. parahaemolyticus genes VP_RS08405, VP_RS01045, VP_RS12170, and VP_RS00880 exhibiting homology to the secondary acyltransferases in Escherichia coli. In this study, the gene VP_RS12170 was identified as a specific lipid A secondary hydroxy-acyltransferase responsible for transferring a 3-hydroxymyristate to the 2'-position of lipid A. Four E. coli mutant strains WHL00, WHM00, WH300, and WH001 were constructed, and they would synthesize lipid A with different structures due to the absence of genes encoding lipid A secondary acyltransferases or Kdo transferase. Then V. parahaemolyticus VP_RS12170 was overexpressed in W3110, WHL00, WHM00, WH300, and WH001, and lipid A was isolated from these strains and analyzed by using thin-layer chromatography and high-performance liquid chromatography-tandem mass spectrometry. The detailed structural changes of lipid A in these mutant strains with and without VP_RS12170 overexpression were compared and conclude that VP_RS12170 can specifically transfer a 3-hydroxymyristate to the 2'-position of lipid A. This study also demonstrated that the function of VP_RS12170 is Kdo-dependent and its favorite substrate is Kdo-lipid IVA. These findings give us better understanding the biosynthetic pathway and the structural diversity of V. parahaemolyticus lipid A.


Assuntos
Lipídeo A , Vibrio parahaemolyticus , Lipídeo A/química , Lipídeo A/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Espectrometria de Massas
2.
Microbiol Res ; 284: 127720, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38640767

RESUMO

Imbalance in carbon flux distribution is one of the most important factors affecting the further increase in the yield of high value-added natural products in microbial metabolic engineering. Meanwhile, the most common inducible expression systems are difficult to achieve industrial-scale production due to the addition of high-cost or toxic inducers during the fermentation process. Quorum sensing system, as a typical model for density-dependent induction of gene expression, has been widely applied in synthetic biology. However, there are currently few reports for efficient production of microbial natural products by using quorum sensing system to self-regulate carbon flux distribution. Here, we designed an artificial quorum sensing system to achieve efficient production of L-threonine in engineered Escherichia coli by altering the carbon flux distribution of the central metabolic pathways at specific periods. Under the combination of switch module and production module, the system was applied to divide the microbial fermentation process into two stages including growth and production, and improve the production of L-threonine by self-inducing the expression of pyruvate carboxylase and threonine extracellular transporter protease after a sufficient amount of cell growth. The final strain TWF106/pST1011, pST1042pr could produce 118.2 g/L L-threonine with a yield of 0.57 g/g glucose and a productivity of 2.46 g/(L· h). The establishment of this system has important guidance and application value for the production of other high value-added chemicals in microorganisms by self-regulation.

3.
World J Microbiol Biotechnol ; 40(5): 159, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607454

RESUMO

Gamma-aminobutyric acid (GABA) is a non-protein amino acid which is widely applied in agriculture and pharmaceutical additive industries. GABA is synthesized from glutamate through irreversible α-decarboxylation by glutamate decarboxylase. Recently, microbial synthesis has become an inevitable trend to produce GABA due to its sustainable characteristics. Therefore, reasonable microbial platform design and metabolic engineering strategies for improving production of GABA are arousing a considerable attraction. The strategies concentrate on microbial platform optimization, fermentation process optimization, rational metabolic engineering as key metabolic pathway modification, promoter optimization, site-directed mutagenesis, modular transporter engineering, and dynamic switch systems application. In this review, the microbial producers for GABA were summarized, including lactic acid bacteria, Corynebacterium glutamicum, and Escherichia coli, as well as the efficient strategies for optimizing them to improve the production of GABA.


Assuntos
Corynebacterium glutamicum , Ácido gama-Aminobutírico , Agricultura , Corynebacterium glutamicum/genética , Indústria Farmacêutica , Engenharia , Escherichia coli/genética
4.
Nat Commun ; 15(1): 2051, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448408

RESUMO

Transmembrane channels play a vital role in regulating the permeation process, and have inspired recent development of biomimetic channels. Herein, we report a class of artificial biomimetic nanochannels based on DNAzyme-functionalized glass nanopipettes to realize delicate control of channel permeability, whereby the surface wettability and charge can be tuned by metal ions and DNAzyme-substrates, allowing reversible conversion between different permeability states. We demonstrate that the nanochannels can be reversibly switched between four different permeability states showing distinct permeability to various functional molecules. By embedding the artificial nanochannels into the plasma membrane of single living cells, we achieve selective transport of dye molecules across the cell membrane. Finally, we report on the advanced functions including gene silencing of miR-21 in single cancer cells and selective transport of Ca2+ into single PC-12 cells. In this work, we provide a versatile tool for the design of rectifying artificial nanochannels with on-demand functions.


Assuntos
DNA Catalítico , Membrana Celular , Biomimética , Inativação Gênica , Permeabilidade
5.
Anal Chem ; 96(14): 5702-5710, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38538555

RESUMO

Glass nanopipets have been demonstrated to be a powerful tool for the sensing and discrimination of biomolecules, such as DNA strands with different lengths or configurations. Despite progress made in nanopipet-based sensors, it remains challenging to develop effective strategies that separate and sense in one operation. In this study, we demonstrate an agarose gel-filled nanopipet that enables hyphenated length-dependent separation and electrochemical sensing of short DNA fragments based on the electrokinetic flow of DNA molecules in the nanoconfined channel at the tip of the nanopipet. This nanoconfined electrokinetic chromatography (NEC) method is used to distinguish the mixture of DNA strands without labels, and the ionic current signals measured in real time show that the mixed DNA strands pass through the tip hole in order according to the molecular weight. With NEC, gradient separation and electrochemical measurement of biomolecules can be achieved simultaneously at the single-molecule level, which is further applied for programmable gene delivery into single living cells. Overall, NEC provides a multipurpose platform integrating separation, sensing, single-cell delivery, and manipulation, which may bring new insights into advanced bioapplication.


Assuntos
DNA , Nanotecnologia , DNA/química , Nanotecnologia/métodos , Cromatografia
6.
Heliyon ; 10(5): e27071, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38463784

RESUMO

Background: Lung cancer metastasis to the brain presents significant clinical challenges. Therefore, elucidating its underlying mechanisms and characterizing its transcriptomic landscape is essential for developing therapeutic interventions. Methods: We analyzed two distinct single-cell RNA sequencing datasets of lung cancer metastasis to analyze the evolutionary trajectory of brain metastatic tumors. In addition, a systematic comparison of cell-cell interaction between tumor cells and lymphocytes was conducted within primary and brain metastatic tumors. Results: The brain metastatic tumors showed greater transcriptomic changes (reflected by a higher pseudotime) than tumors in the lymph nodes and primary tumors. Furthermore, our investigation has not only revealed specific shared ligand-receptor pairs in both mLN and mBrain, exemplified by the interaction between SPP1 and CD99 in T cells, but has also unveiled a diverse array of ligand-receptor pairs exclusive to the mBrain. Notably, this includes distinctive pairs such as APP and IL1 observed specifically in myeloid cells. Conclusion: The distinct microenvironment in the brain may influence the observed transcriptomic changes in tumors, emphasizing the significance of the specific environment in determining tumor behavior and therapeutic response.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38344778

RESUMO

PURPOSE: Distinguishing different types of diabetes is important in directing optimized treatment strategies and correlated epidemiological studies. Through detailed analysis of hormone responses to mixed meal tolerance test (MMTT), we aimed to find representing characteristics of post-acute pancreatitis diabetes mellitus (PPDM-A) and post-chronic pancreatitis diabetes mellitus (PPDM-C). METHODS: Participants with PPDM-A, PPDM-C, type 1 diabetes, type 2 diabetes and normal controls underwent MMTT. Fasting and postprandial responses of serum glucose, C-peptide, insulin, glucagon, pancreatic polypeptide (PP), ghrelin, gastric inhibitory peptide (GIP), glucagon like peptide-1 (GLP-1) and peptide YY (PYY) were detected and compared among different groups. Focused analysis on calculated insulin sensitivity and secretion indices were performed to reason major causes of hyperglycemia in different conditions. RESULTS: Participants with PPDM-A were characterized by increased C-peptide, insulin, glucagon and PP, while decreased ghrelin, GIP and PYY compared with controls. Patients with PPDM-C showed secretion insufficiency of C-peptide, insulin, ghrelin and PYY, higher postprandial responses of glucagon and PP than controls. In particular, both fasting and postprandial levels of ghrelin in PPDM-C were significantly lower than other diabetes groups. PYY responses in patients with PPDM-A and PPDM-C were markedly reduced. Besides, the insulin sensitivity of PPDM-A was decreased, and the insulin secretion for PPDM-C was decreased. CONCLUSIONS: Along with the continuum from acute to chronic pancreatitis, the pathological mechanism of PPDM changes from insulin resistance to insulin deficiency. Insufficient PYY secretion is a promising diagnostic marker for distinguishing PPDM from type 1 and type 2 diabetes. Absent ghrelin secretion to MMTT may help identify PPDM-C.

8.
Int J Biol Macromol ; 262(Pt 1): 130066, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340911

RESUMO

Accurate and convenient monitoring of pH under extreme alkaline conditions is still a challenge. In this work, 4-(3-(7-hydroxy-2-oxo-2H-chromen-3-yl)-3-oxoprop-1-en-1-yl)benzamide (HCB), a coumarin derivative, was grafted onto dialdehyde cellulose (DAC) to obtain a sensor DAC-HCB, which exhibited a ratiometric fluorescent response to the pH of alkaline solutions, resulting in a significant fluorescent color change from yellow to blue (FI459 nm/FI577 nm) at pH 7.5-14. The structure of DAC-HCB was characterized through FT-IR, XRD, XPS, SEM. The pKa of sensor DAC-HCB was 13.16, and the fluorescent intensity ratio FI459 nm/FI577 nm possessed an excellent linear characteristic with pH in the scope of 9.0-13.0. Meanwhile, sensor DAC-HCB showed good selectivity, anti-interference, and fast response time to basic pH, which is an effective fluorescent sensor for examination of pH in alkali circumstance. The recognition mechanism of DAC-HCB to OH- was elucidated with HRMS and density-functional theory (DFT) computational analyses. Sensor DAC-HCB was successfully used for precise detection of environmental water samples pH. This work furnished a new protocol for test strips as a convenient and highly efficient pH detection tool for the high pH environment, and it has great potential for application in environmental monitoring.


Assuntos
Celulose , Corantes Fluorescentes , Corantes Fluorescentes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Celulose/química , Cumarínicos/química , Concentração de Íons de Hidrogênio
9.
Intern Emerg Med ; 19(3): 681-688, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38372886

RESUMO

Stress hyperglycemia has been confirmed as a strong predictor of poor short-term prognosis in acute pancreatitis. However, whether stress hyperglycemia affects the long-term prognosis of patients with acute pancreatitis is unclear. We aimed to investigate the effect of stress hyperglycemia on the long-term prognosis of non-diabetic patients with acute pancreatitis. This retrospective observational study was conducted on 4055 patients with acute pancreatitis from 1 January 2016 to 31 October 2020. The association between stress hyperglycemia and the prognosis was evaluated using regression modeling. There were 935(71.5%) normoglycemic and 373(28.5%) stress hyperglycemia patients. 46(12.3%) patients with stress hyperglycemia had evidence of diabetes compared with 33(3.5%) patients without stress hyperglycemia (P < 0.001). After multivariate adjustment, patients with stress hyperglycemia were more likely to have evidence of diabetes (OR 2.905, 95% CI 1.688-4.999) compared with normoglycemic. However, stress hyperglycemia is not associated with the recurrence of pancreatitis and progression to chronic pancreatitis. Stress hyperglycemia was independently associated with diabetes secondary to acute pancreatitis. Accordingly, a follow-up diabetes-screening program for AP with stress hyperglycemia is an important part of identifying the disease as soon as possible, delaying islet damage, and improving the prognosis of post-acute pancreatitis diabetes mellitus.


Assuntos
Hiperglicemia , Pancreatite , Humanos , Masculino , Feminino , Estudos Retrospectivos , Hiperglicemia/complicações , Pessoa de Meia-Idade , Prognóstico , Pancreatite/complicações , Pancreatite/fisiopatologia , Adulto , Idoso , Diabetes Mellitus/epidemiologia
10.
Microb Cell Fact ; 23(1): 55, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368340

RESUMO

BACKGROUND: Pichia pastoris is a widely utilized host for heterologous protein expression and biotransformation. Despite the numerous strategies developed to optimize the chassis host GS115, the potential impact of changes in cell wall polysaccharides on the fitness and performance of P. pastoris remains largely unexplored. This study aims to investigate how alterations in cell wall polysaccharides affect the fitness and function of P. pastoris, contributing to a better understanding of its overall capabilities. RESULTS: Two novel mutants of GS115 chassis, H001 and H002, were established by inactivating the PAS_chr1-3_0225 and PAS_chr1-3_0661 genes involved in ß-glucan biosynthesis. In comparison to GS115, both modified hosts exhibited a looser cell surface and larger cell size, accompanied by faster growth rates and higher carbon-to-biomass conversion ratios. When utilizing glucose, glycerol, and methanol as exclusive carbon sources, the carbon-to-biomass conversion rates of H001 surpassed GS115 by 10.00%, 9.23%, and 33.33%, respectively. Similarly, H002 exhibited even higher increases of 32.50%, 12.31%, and 53.33% in carbon-to-biomass conversion compared to GS115 under the same carbon sources. Both chassis displayed elevated expression levels of green fluorescent protein (GFP) and human epidermal growth factor (hegf). Compared to GS115/pGAPZ A-gfp, H002/pGAPZ A-gfp showed a 57.64% higher GFP expression, while H002/pPICZα A-hegf produced 66.76% more hegf. Additionally, both mutant hosts exhibited enhanced biosynthesis efficiencies of S-adenosyl-L-methionine and ergothioneine. H001/pGAPZ A-sam2 synthesized 21.28% more SAM at 1.14 g/L compared to GS115/pGAPZ A-sam2, and H001/pGAPZ A-egt1E obtained 45.41% more ERG at 75.85 mg/L. The improved performance of H001 and H002 was likely attributed to increased supplies of NADPH and ATP. Specifically, H001 and H002 exhibited 5.00-fold and 1.55-fold higher ATP levels under glycerol, and 6.64- and 1.47-times higher ATP levels under methanol, respectively, compared to GS115. Comparative lipidomic analysis also indicated that the mutations generated richer unsaturated lipids on cell wall, leading to resilience to oxidative damage. CONCLUSIONS: Two novel P. pastoris chassis hosts with impaired ß-1,3-D-glucan biosynthesis were developed, showcasing enhanced performances in terms of growth rate, protein expression, and catalytic capabilities. These hosts exhibit the potential to serve as attractive alternatives to P. pastoris GS115 for various bioproduction applications.


Assuntos
Metanol , Pichia , Saccharomycetales , Humanos , Pichia/metabolismo , Metanol/metabolismo , Glicerol/metabolismo , Trifosfato de Adenosina/metabolismo , Carbono/metabolismo , Parede Celular/metabolismo , Polissacarídeos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
11.
Clin Rheumatol ; 43(3): 959-969, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38305937

RESUMO

OBJECTIVE: Fibroblast-like synoviocytes (FLS) play a critical role on the exacerbation and deterioration of rheumatoid arthritis (RA). Aberrant activation of FLS pyroptosis signaling is responsible for the hyperplasia of synovium and destruction of cartilage of RA. This study investigated the screened traditional Chinese medicine berberine (BBR), an active alkaloid extracted from the Coptis chinensis plant, that regulates the pyroptosis of FLS and secretion of inflammatory factors in rheumatoid arthritis. METHODS: First, BBR was screened using a high-throughput drug screening strategy, and its inhibitory effect on RA-FLS was verified by in vivo and in vitro experiments. Second, BBR was intraperitoneally administrated into the collagen-induced arthritis rat model, and the clinical scores, arthritis index, and joint HE staining were evaluated. Third, synovial tissues of CIA mice were collected, and the expression of NLRP3, cleaved-caspase-1, GSDMD-N, Mst1, and YAP was detected by Western blot. RESULTS: The administration of BBR dramatically alleviated the severity of collagen-induced arthritis rat model with a decreased clinical score and inflammation reduction. In addition, BBR intervention significantly attenuates several pro-inflammatory cytokines (interleukin-1ß, interleukin-6, interleukin-17, and interleukin-18). Moreover, BBR can reduce the pyroptosis response (caspase-1, NLR family pyrin domain containing 3, and gasdermin D) of the RA-FLS in vitro, activating the Hippo signaling pathway (Mammalian sterile 20-like kinase 1, yes-associated protein, and transcriptional enhanced associate domains) so as to inhibit the pro-inflammatory effect of RA-FLS. CONCLUSION: These results support the role of BBR in RA and may have therapeutic implications by directly repressing the activation, migration of RA-FLS, which contributing to the attenuation of the progress of CIA. Therefore, targeting PU.1 might be a potential therapeutic approach for RA. Besides, BBR inhibited RA-FLS pyroptosis by downregulating of NLRP3 inflammasomes (NLRP3, caspase-1) and eased the pro-inflammatory activities via activating the Hippo signaling pathway, thereby improving the symptom of CIA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Berberina , Ratos , Camundongos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Berberina/farmacologia , Berberina/uso terapêutico , Berberina/metabolismo , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/metabolismo , Membrana Sinovial/metabolismo , Caspases/metabolismo , Caspases/farmacologia , Caspases/uso terapêutico , Fibroblastos/metabolismo , Células Cultivadas , Proliferação de Células , Mamíferos
12.
Pharmacol Res ; 200: 107071, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38218354

RESUMO

Plant-derived exosome-like nanoparticles (ELNs) have drawn considerable attention for oral treatment of colonic diseases. However, the roles of ELNs derived from garlic on colitis remain unclear. Here, we demonstrate that garlic ELNs (GELNs), with desirable particle sizes (79.60 nm) and trafficking large amounts of functional proteins and microRNAs, stably roam in the gut and confer protection against ulcerative colitis (UC). In mice with DSS-induced colitis, orally administered GELNs effectively ameliorated bloody diarrhea, normalized the production of proinflammatory cytokines, and prevented colonic barrier impairment. Mechanistically, GELNs were taken up by gut microbes and reshaped DSS-induced gut microbiota dysbiosis, in which Bacteroides was the dominant respondent genus upon GELNs treatment. Notably, GELNs-enriched peu-MIR2916-p3 specifically promoted the growth of Bacteroides thetaiotaomicron, an intestinal symbiotic bacterium with palliative effects on colitis. Our findings provide new insights into the medicinal application of GELNs and highlight their potential as natural nanotherapeutic agents for preventing and treating UC.


Assuntos
Bacteroides thetaiotaomicron , Colite Ulcerativa , Colite , Exossomos , Alho , Microbioma Gastrointestinal , Camundongos , Animais , Exossomos/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/microbiologia , Colo , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
13.
Anal Chem ; 96(4): 1506-1514, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38215343

RESUMO

The localized surface-plasmon resonance of the AuNP in aqueous media is extremely sensitive to environmental changes. By measuring the signal of plasmon scattering light, the dark-field microscopic (DFM) imaging technique has been used to monitor the aggregation of AuNPs, which has attracted great attention because of its simplicity, low cost, high sensitivity, and universal applicability. However, it is still challenging to interpret DFM images of AuNP aggregation due to the heterogeneous characteristics of the isolated and discontinuous color distribution. Herein, we introduce machine vision algorithms for the training of DFM images of AuNPs in different saline aqueous media. A visual deep learning framework based on AlexNet is constructed for studying the aggregation patterns of AuNPs in aqueous suspensions, which allows for rapid and accurate identification of the aggregation extent of AuNPs, with a prediction accuracy higher than 0.96. With the aid of machine learning analysis, we further demonstrate the prediction ability of various aggregation phenomena induced by both cation species and the concentration of the external saline solution. Our results suggest the great potential of machine vision frameworks in the accurate recognition of subtle pattern changes in DFM images, which can help researchers build predictive analytics based on DFM imaging data.

14.
Mol Pharm ; 21(2): 760-769, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38175712

RESUMO

Acoustic kinetic therapy systems that target specific organelles can improve the precision of a sonosensitizer, which is a perfect combination of targeted therapy and sonodynamic therapy (SDT) and plays an important role in current acoustic kinetic therapy. In this study, we loaded PpIX, a sonosensitizer, on targeted-functional carbon dots (CDs) via an amide reaction and then generated the mitochondria-targeted system (Mit-CDs-PpIX) and nucleus-targeted system (Nuc-CDs-PpIX), respectively, to deliver the sonosensitizer. Both systems exhibited minimal cytotoxicity in the absence of ultrasound stimulation. The efficacy of the targeted SDT systems was investigated using methylthiazol tetrazolium (MTT) assays, live/dead staining, flow cytometry, etc. Compared with the free PpIX and mitochondria-targeted system, the nucleus-targeted system is more potent in killing effect under ultrasound stimulation and induces apoptosis with higher intensity. To achieve the equal killing effect, the effective concentration of Nuc-CDs-PpIX is just one third of that of Mit-CDs-PpIX.


Assuntos
Terapia por Ultrassom , Apoptose , Mitocôndrias , Espécies Reativas de Oxigênio , Linhagem Celular Tumoral
15.
Adv Sci (Weinh) ; 11(7): e2306125, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38044318

RESUMO

Multi-layered plasmonic nanostructures are able to highly promote the near-field confinement and effectively activate analytes, which are of predominate significance but are extremely challenging. Herein, the semi-open Au core@carved AuAg multi-shell superstructure nanoparticles (multi-Au@Ag-Au NPs, multi = mono, bi, tri, tetra, and penta) are reported with a high designability on electromagnetic field and capability of effectively capturing analytes. By controlling synthetic parameters such as the number of galvanic exchange and Ag growth, multi-Au@Ag-Au NPs are successfully obtained, with tunable layer numbers and asymmetric nanoholes. Due to collective plasmon oscillations of multi-layered built-in nanogaps, the electromagnetic field strength of a single penta-Au@Ag-Au entity reach 48841. More importantly, the penta-Au@Ag-Au NPs show a remarkable light-harvesting capability, which is adaptive to different Raman lasers, supporting high-diversity detection. Additionally, the structural specificity allows analytes to be sufficiently captured into interior hotspots, and further achieve highly sensitive detection with limit of detection down to 3.22 × 10-12  M. This study not only provides an effective pathway for integrating abundant hotspots and activating target molecules in single plasmonic superstructure, but stimulates advancements in SERS substrates for various applications.

16.
Fish Physiol Biochem ; 50(2): 785-796, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38108936

RESUMO

To elucidate the underlying mechanism of the energy metabolism in largemouth bass (Micropterus salmoides), cultured fish (initial body weight: 77.57 ± 0.75 g) in the present study were starved for 0 h, 12 h, 24 h, 48 h, 96 h and 192 h, respectively. The proximate composition analysis showed that short-term starvation induced a significant up-regulation in crude protein proportion in hepatic of cultured fish (P < 0.05). However, short-term starvation significantly decreased the hepatosomatic index and the viscerosomatic index of cultured fish (P < 0.05). The exact hepatic glycogen content in the group starved for 92 h presented remarkable decrease (P < 0.05). Meanwhile, compared with the weight change of lipid and protein (mg) in hepatic (y = 0.0007x2 - 0.2827x + 49.402; y = 0.0013x2 - 0.5666x + 165.31), the decreasing trend of weight in glycogen (mg) was more pronounced (y = 0.0032x2 - 1.817x + 326.52), which suggested the preferential utilization of hepatic glycogen as energy substrates under short-term starvation. Gene expression analysis revealed that the starvation down-regulated the expression of insulin-like growth factor 1 and genes of TOR pathway, such as target of rapamycin (tor) and ribosomal protein S6 (s6) (P < 0.05). In addition, the starvation significantly enhanced expression of lipolysis-related genes, including hormone-sensitive lipase (hsl) and carnitine palmitoyl transferase I (cpt1), but down-regulated lipogenesis as indicated by the inhibited expression of fatty acids synthase (fas), acetyl-CoA carboxylase 1 (acc1) and acetyl-CoA carboxylase 2 (acc2) (P < 0.05). Starvation of 24 h up-regulated the expression of glycolysis genes, glucokinase (gk), phosphofructokinase liver type (pfkl) and pyruvate kinase (pk), and then their expression returned to the normal level. Meanwhile, the expression of gluconeogenesis genes, such as glucose-6-phosphatase catalytic subunit (g6pc), fructose-1,6-bisphosphatase-1 (fbp1) and phosphoenolpyruvate carboxy kinase (pepck), was significantly inhibited with the short-term starvation (P < 0.05). In conclusion, short-term starvation induced an overall decline in growth performance, but it could deplete the hepatic glycogen accumulation and mobilize glycogen for energy effectively.


Assuntos
Bass , Animais , Glicogênio Hepático/metabolismo , Acetil-CoA Carboxilase/metabolismo , Lipogênese , Glicogênio/metabolismo , Proteínas/metabolismo , Fígado/metabolismo
17.
Foodborne Pathog Dis ; 21(3): 174-182, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38112720

RESUMO

Cronobacter sakazakii, an opportunistic milk-borne pathogen responsible for severe neonatal meningitis and bacteremia, can synthesize yellow pigment (various carotenoids) benefiting for bacterial survival, while little literature was available about the influence of various carotenoids on bacterial resistance to a series of stresses and the characteristics of cell membrane, obstructing the development of novel bactericidal strategies overcoming the strong tolerance of C. sakazakii. Thus in this study, for the first time, five carotenogenic genes of C. sakazakii BAA-894 were inactivated, respectively, to construct a series of mutants producing various carotenoids and their effects on the cell membrane properties, and resistances to food- and host-related stresses, were investigated systematically. Furthermore, to explore its possible mode of action, comparative lipidomics analysis was performed to reveal the change of lipids that were mainly located at cell membranes. The results showed that five mutants (ΔcrtB, ΔcrtI, ΔcrtY, ΔcrtZ, and ΔcrtX) displayed negligible change in growth rate but higher permeability of the outer membrane and lower fluidity of cell membrane compared to the wild type. Besides, these mutants exhibited poorer ability of biofilm formation and lower resistances to acid, oxidative, osmotic, and desiccation stresses, indicating that different carotenoid composition significantly affected environmental tolerance of C. sakazakii. To discover the possible causes, lipidomics analysis of C. sakazakii was conducted and more than 500 lipid species belonging to 27 classes had been identified at first. Compared to that of BAA-894, the composition and relative intensity of lipid species in five mutants varied significantly, especially the monounsaturated and biunsaturated phosphatidylethanolamine. The evidence presented in this study demonstrated that the varied composition of carotenoids in C. sakazakii significantly altered the lipid profile and intensity, which maybe a crucial means to influencing the characteristics of cell membranes and resistance to environmental stresses.


Assuntos
Cronobacter sakazakii , Cronobacter , Recém-Nascido , Humanos , Cronobacter sakazakii/genética , Carotenoides/metabolismo , Estresse Fisiológico , Lipídeos
18.
Int J Surg ; 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38051925

RESUMO

BACKGROUND: Neoadjuvant administration of immune checkpoint inhibitors (ICIs) combined with chemotherapy demonstrated promising efficacy and manageable safety in locally advanced esophageal squamous cell carcinoma (ESCC). This prospective, single-arm, phase 2 study evaluated the efficacy and safety of neoadjuvant therapy with camrelizumab plus paclitaxel and nedaplatin for 2-4 cycles in ESCC. METHODS: Patients with locally advanced stage IIa-IIIb ESCC were enrolled in the study and received camrelizumab (200 mg), paclitaxel (155 mg/m2), and nedaplatin (80 mg/m2) intravenously on day one every three weeks. Patients underwent surgery after 2-4 cycles of treatment regimes. The primary endpoint was the pathological complete response (pCR) rate. Secondary endpoints included the major pathological response (MPR) rate, R0 resection rate, tumor regression, objective response rate (ORR), and disease-free survival (DFS). Programmed cell death 1 ligand 1 (PD-L1) expression in tumor tissues was measured and quantified using immunohistochemistry staining and combined positive score (CPS), respectively. RESULTS: In total, 75 patients were enrolled and received neoadjuvant treatment. Of them, 45 (60%) received two cycles, 18 (24%) received three cycles, and 10 patients (13.3%) received four cycles of neoadjuvant therapy. Ultimately, 62 (82.7%) patients underwent surgery. Patients achieved a pCR of 27.4% (95% CI 16.9-40.2), an MPR of 45.2% (95% CI 33.1-59.2), and an ORR of 48.4% (95% CI 35.5-61.4); all patients had an R0 resection. T and N downstaging occurred in 55 (88.7%) and 27 patients (43.5%). Moreover, ESCC patients with CPS ≥ 10 tended to have enhanced ORR, pCR, and MPR compared to those with CPS < 10. Treatment-related adverse events (TRAEs) of grade 1-2 occurred in 59 (78.7%) patients, grade 3 TRAEs in four (5.3%), and one patient (1.3%) experienced a grade 4 TRAE. CONCLUSIONS: Neoadjuvant camrelizumab combined with chemotherapy showed promising efficacy in locally advanced ESCC, with a manageable safety profile, when administered flexibly in two to four cycles.

19.
Front Microbiol ; 14: 1272691, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029125

RESUMO

The objective of this study was to evaluate the potential modulating effects of Allium mongolicum regel ethanol extract (AME) on rumen fermentation and biohydrogenation (BH) bacteria in vitro. Four Holstein cows were used as donors for the rumen fluid used in this study. In experiment 1, five treatments (supplemented with 0 mg/g, 1 mg/g, 2 mg/g, 3 mg/g, and 4 mg/g of AME based on fermentation substrate, respectively) were conducted to evaluate the effects of different levels of AME on fermentation status in vitro. The results showed that after 24 h of fermentation, MCP was reduced with AME supplementation (p < 0.05), and the multiple combinations of different combinations index (MFAEI) value was the highest with 3 mg/g of AME. In experiment 2, six treatments were constructed which contained: control group (A1); the unsaturated fatty acid (UFA) mixture at 3% concentration (A2); the mixture of A2 and 3 mg/g of AME (A3); 3 mg/g of AME (A4); the UFA mixture at 1.5% concentration (A5); the mixture of A5 and 3 mg/g of AME (A6). The abundance of bacterial species involved in BH was measured to evaluate the potential modulating effect of AME on rumen BH in vitro. Compared with the A1 group, the A3, A4, and A6 groups both showed significant decreases in the abundance of rumen BH microbial flora including Butyrivibrio proteoclasticus, Butyrivibrio fibrisolvens, Ruminococcus albus and Clostridium aminophilum (p < 0.01). The A3 group was less inhibitory than A4 in the abundance of B. proteoclasticus, B. fibrisolvens, and R. albus, and the inhibitory effect of the A6 group was higher than that of A4. In conclusion, the supplementation with 3 mg/g of AME could modulate the rumen fermentation and affect BH key bacteria, which suggests that AME may have the potential to inhibit the rumen BH of dairy cows.

20.
Micromachines (Basel) ; 14(10)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37893333

RESUMO

This paper proposes a unique memristor-based design scheme for a balanced ternary digital logic circuit. First, a design method of a single-variable logic function circuit is proposed. Then, by combining with a balanced ternary multiplexer, some common application-type combinational logic circuits are proposed, including a balanced ternary half adder, multiplier and numerical comparator. The above circuits are all simulated and verified in LTSpice, which demonstrate the feasibility of the proposed scheme.

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