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1.
Nat Commun ; 15(1): 5760, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982046

ABSTRACT

Artificial wrinkles, especially those with responsive erasure/regeneration behaviors have gained extensive interest due to their potential in smart applications. However, current wrinkle modulation methods primarily rely on network rearrangement, causing bottlenecks in in situ wrinkle regeneration. Herein, we report a dually cross-linked network wherein [2]rotaxane cross-link can dissipate stress within the wrinkles through its sliding motion without disrupting the network, and quadruple H-bonding cross-link comparatively highlight the advantages of [2]rotaxane modulation. Acid stimulation dissociates quadruple H-bonding and destructs network, swiftly eliminating the wrinkles. However, the regeneration process necessitates network rearrangement, making in situ recovery unfeasible. By contrast, alkaline stimulation disrupts host-guest recognition, and subsequent intramolecular motion of [2]rotaxane dissipate energy to eliminate wrinkles gradually. The always intact network allows for the in situ recovery of surface microstructures. The responsive behaviors of quadruple H-bonding and mechanical bond are orthogonal, and their combination leads to wrinkles with multiple but accurate responsiveness.

2.
Talanta ; 278: 126516, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38972276

ABSTRACT

The residues of organophosphorus pesticides (OPs) are increasing environmental pollution and public health concerns. Thus, the development of simple, convenient and sensitive method for detection of OPs is crucial. Herein, a multifunctional Fe-based MOF with fluorescence, catalytic and adsorption, is synthesized by a simple one-pot hydrothermal method. The ratiometric fluorescence sensor for detection of OPs is constructed by using only one multifunctional sensing material. The NH2-MIL-101(Fe) is able catalyze the o-phenylenediamine (OPD) into 2,3-diaminophenazine (DAP) in the presence of H2O2. The generated DAP can significantly quench the intrinsic fluorescence of NH2-MIL-101(Fe) by the fluorescence resonance energy transfer (FRET) and internal filtration effect (IFE), while producing a new measurable fluorescence. Without immobilization or molecular imprinting, pyrophosphate ion (PPi) can inhibit the peroxidase-like activity of the NH2-MIL-101(Fe) by chelating with Fe3+/Fe2+ redox couple. Moreover, PPi can also be hydrolyzed by alkaline phosphatase (ALP), the presence of OPs inhibits the activity of ALP, resulting in the increase of extra PPi preservation and signal changes of ratiometric fluorescence, the interactions of ALP with different OPs are explored by molecular docking, the OPs (e.g., glyphosate) interact with crucial amino acid residues (Asp, Ser, Ala, Lys and Arg) are indicated. The proposed sensor exhibits excellent detection performance for OPs with the detection limit of 18.7 nM, which provides a promising strategy for detection of OPs.

3.
Angew Chem Int Ed Engl ; : e202410834, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949776

ABSTRACT

Type I main-chain polyrotaxanes (PRs) with multiple wheels threaded onto the axle are widely employed to design slide-ring materials. However, Type II main-chain PRs with axles threading into the macrocycles on the polymer backbones have rarely been studied, although they feature special topological structures and dynamic characteristics. Herein, we report the design and preparation of Type II main-chain PR-based mechanically interlocked networks (PRMINs), based on which the relationship between microscopic motion of mechanical bonds on the PRs and macroscopic mechanical performance of materials has been revealed. The representative PRMIN-2 exhibits a robust feature in tensile tests with high stretchability (1680%) and toughness (47.5 MJ/m3). Moreover, it also has good puncture performance with puncture energy of 22.0 mJ. Detailed rheological measurements and coarse-grained molecular dynamics (CGMD) simulation reveal that the embedded multiple [2]rotaxane mechanical bonds on the PR backbones of PRMINs could undergo a synergistic long-range sliding motion under external force, with the introduction of collective dangling chains into the network. As a result, the synchronized motions of coherent PR chains can be readily activated to accommodate network deformation and efficiently dissipate energy, thereby leading to enhanced mechanical performances of PRMINs.

4.
J Phys Chem Lett ; : 7133-7140, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38959198

ABSTRACT

Charge transfer efficiencies in all-inorganic lead halide perovskite nanocrystals (NCs) are crucial for applications in photovoltaics and photocatalysis. Herein, CsPbBr3 NCs with different sizes are synthesized by varying the ligand contents of didodecyl dimethylammonium bromide at room temperature. Adding benzoquinone (BQ) molecules leads to a decrease in the PL intensities and PL decay times in NCs. The electron transfer (ET) efficiency (ηET) increases with NC size in complexes of CsPbBr3 NCs and BQ molecules (NC-BQ complexes), when the same concentration of BQ is maintained, as investigated by transient photobleaching and photoluminescence spectroscopies. Controlling the same number of attached BQ acceptor molecules per NC induces the same ηET in NC-BQ complexes even though with different NC sizes. Our findings provide new insights into ultrafast charge transfer behaviors in perovskite NCs, which is important for designing efficient light energy conversion devices.

5.
Front Cell Infect Microbiol ; 14: 1397724, 2024.
Article in English | MEDLINE | ID: mdl-38966251

ABSTRACT

Cryptococcus neoformans is at the top of the list of "most wanted" human pathogens. Only three classes of antifungal drugs are available for the treatment of cryptococcosis. Studies on antifungal resistance mechanisms are limited to the investigation of how a particular antifungal drug induces resistance to a particular drug, and the impact of stresses other than antifungals on the development of antifungal resistance and even cross-resistance is largely unexplored. The endoplasmic reticulum (ER) is a ubiquitous subcellular organelle of eukaryotic cells. Brefeldin A (BFA) is a widely used chemical inducer of ER stress. Here, we found that both weak and strong selection by BFA caused aneuploidy formation in C. neoformans, mainly disomy of chromosome 1, chromosome 3, and chromosome 7. Disomy of chromosome 1 conferred cross-resistance to two classes of antifungal drugs: fluconazole and 5-flucytosine, as well as hypersensitivity to amphotericin B. However, drug resistance was unstable, due to the intrinsic instability of aneuploidy. We found overexpression of AFR1 on Chr1 and GEA2 on Chr3 phenocopied BFA resistance conferred by chromosome disomy. Overexpression of AFR1 also caused resistance to fluconazole and hypersensitivity to amphotericin B. Furthermore, a strain with a deletion of AFR1 failed to form chromosome 1 disomy upon BFA treatment. Transcriptome analysis indicated that chromosome 1 disomy simultaneously upregulated AFR1, ERG11, and other efflux and ERG genes. Thus, we posit that BFA has the potential to drive the rapid development of drug resistance and even cross-resistance in C. neoformans, with genome plasticity as the accomplice.


Subject(s)
Aneuploidy , Antifungal Agents , Brefeldin A , Cryptococcus neoformans , Drug Resistance, Fungal , Cryptococcus neoformans/drug effects , Cryptococcus neoformans/genetics , Brefeldin A/pharmacology , Antifungal Agents/pharmacology , Drug Resistance, Fungal/genetics , Fluconazole/pharmacology , Amphotericin B/pharmacology , Fungal Proteins/genetics , Fungal Proteins/metabolism , Microbial Sensitivity Tests , Flucytosine/pharmacology , Humans , Endoplasmic Reticulum Stress/drug effects
6.
Hortic Res ; 11(6): uhae105, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38883332

ABSTRACT

Saposhnikovia divaricata, 2n = 2x = 16, as a perennial species, is widely distributed in China, Mongolia, Russia, etc. It is a traditional Chinese herb used to treat tetanus, rubella pruritus, rheumatic arthralgia, and other diseases. Here, we assembled a 2.07 Gb and N50 scaffold length of 227.67 Mb high-quality chromosome-level genome of S. divaricata based on the PacBio Sequel II sequencing platform. The total number of genes identified was 42 948, and 42 456 of them were functionally annotated. A total of 85.07% of the genome was composed of repeat sequences, comprised mainly of long terminal repeats (LTRs) which represented 73.7% of the genome sequence. The genome size may have been affected by a recent whole-genome duplication event. Transcriptional and metabolic analyses revealed bolting and non-bolting S. divaricata differed in flavonoids, plant hormones, and some pharmacologically active components. The analysis of its genome, transcriptome, and metabolome helped to provide insights into the evolution of bolting and non-bolting phenotypes in wild and cultivated S. divaricata and lays the basis for genetic improvement of the species.

7.
Materials (Basel) ; 17(11)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38893979

ABSTRACT

The Laasraoui segmented and Arrhenius flow stress model, dynamic recrystallization (DRX) model, grain size prediction model, and hot processing map (HPM) of Fe-Cr-Mo-Mn steels were established through isothermal compression tests. The models and HPM were proven by experiment to be highly accurate. As the deformation temperature decreased or the strain rate increased, the flow stress increased and the grain size of the Fe-Cr-Mo-Mn steel decreased, while the volume fraction of DRX (Xdrx) decreased. The optimal range of the hot processing was determined to be 1050-1200 °C/0.369-1 s-1. Zigzag-like grain boundaries (GBs) and intergranular cracks were found in the unstable region, in which the disordered martensitic structure was observed. The orderly packet martensite was formed in the general processing region, and the mixed structure with incomplete DRX grains was composed of coarse and fine grains. The microstructure in the optimum processing region was composed of DRX grains and the multistage martensite. The validity of the Laasraoui segmented flow stress model, DRX model, grain size prediction model, and HPM was verified by upsetting tests.

8.
Biosensors (Basel) ; 14(6)2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38920598

ABSTRACT

A microfluidic sweat monitoring patch that collects human sweat for a long time is designed to achieve the effect of detecting the rise and fall of human sweat glucose over a long period of time by increasing the use time of a single patch. Five collection pools, four serpentine channels, and two different valves are provided. Among them, the three-dimensional valve has a large burst pressure as a balance between the internal and external air pressures of the patch. The bursting pressure of the two-dimensional diverter valve is smaller than that of the three-dimensional gas valve, and its role is to control the flow direction of the liquid. Through plasma hydrophilic treatment of different durations, the optimal hydrophilic duration is obtained. The embedded chromogenic disc detects the sweat glucose value at two adjacent time intervals and compares the information of the human body to increase or reduce glucose. The patch has good flexibility and can fit well with human skin, and because polydimethylsiloxane (PDMS) has good light transmission, it reduces the measurement error caused by the color-taking process and makes the detection results more accurate.


Subject(s)
Sweat , Humans , Sweat/chemistry , Hypoglycemia , Glucose/analysis , Biosensing Techniques , Microfluidics , Dimethylpolysiloxanes/chemistry , Blood Glucose/analysis
9.
ACS Chem Biol ; 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38912881

ABSTRACT

Eliminating the core fucose from the N-glycans of the Fc antibody segment by pathway engineering or enzymatic methods has been shown to enhance the potency of therapeutic antibodies, especially in the context of antibody-dependent cytotoxicity (ADCC). However, there is a significant challenge due to the limited defucosylation efficiency of commercially available α-l-fucosidases. In this study, we report a unique α-l-fucosidase (PnfucA) from the bacterium Prevotella nigrescens that has a low sequence identity compared with all other known α-l-fucosidases and is highly reactive toward a core disaccharide substrate with fucose α(1,3)-, α (1,4)-and α(1,6)-linked to GlcNAc, and is less reactive toward the Fuc-α(1,2)-Gal on the terminal trisaccharide of the oligosaccharide Globo H (Bb3). The kinetic properties of the enzyme, such as its Km and kcat, were determined and the optimized expression of PnfucA gave a yield exceeding 30 mg/L. The recombinant enzyme retained its full activity even after being incubated for 6 h at 37 °C. Moreover, it retained 92 and 87% of its activity after freezing and freeze-drying treatments, respectively, for over 28 days. In a representative glycoengineering of adalimumab (Humira), PnfucA showed remarkable hydrolytic efficiency in cleaving the α(1,6)-linked core fucose from FucGlcNAc on the antibody with a quantitative yield. This enabled the seamless incorporation of biantennary sialylglycans by Endo-S2 D184 M in a one-pot fashion to yield adalimumab in a homogeneous afucosylated glycoform with an improved binding affinity toward Fcγ receptor IIIa.

10.
Redox Biol ; 74: 103229, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38870781

ABSTRACT

BACKGROUND: Nuclear erythroid 2-related factor 2 (Nrf2), a transcription factor, is critically involved in the regulation of oxidative stress and inflammation. However, the role of endothelial Nrf2 in atherogenesis has yet to be defined. In addition, how endothelial Nrf2 is activated and whether Nrf2 can be targeted for the prevention and treatment of atherosclerosis is not explored. METHODS: RNA-sequencing and single-cell RNA sequencing analysis of mouse atherosclerotic aortas were used to identify the differentially expressed genes. In vivo endothelial cell (EC)-specific activation of Nrf2 was achieved by injecting adeno-associated viruses into ApoE-/- mice, while EC-specific knockdown of Nrf2 was generated in Cdh5CreCas9floxed-stopApoE-/- mice. RESULTS: Endothelial inflammation appeared as early as on day 3 after feeding of a high cholesterol diet (HCD) in ApoE-/- mice, as reflected by mRNA levels, immunostaining and global mRNA profiling, while the immunosignal of the end-product of lipid peroxidation (LPO), 4-hydroxynonenal (4-HNE), started to increase on day 10. TNF-α, 4-HNE, and erastin (LPO inducer), activated Nrf2 signaling in human ECs by increasing the mRNA and protein expression of Nrf2 target genes. Knockdown of endothelial Nrf2 resulted in augmented endothelial inflammation and LPO, and accelerated atherosclerosis in Cdh5CreCas9floxed-stopApoE-/- mice. By contrast, both EC-specific and pharmacological activation of Nrf2 inhibited endothelial inflammation, LPO, and atherogenesis. CONCLUSIONS: Upon HCD feeding in ApoE-/- mice, endothelial inflammation is an earliest event, followed by the appearance of LPO. EC-specific activation of Nrf2 inhibits atherosclerosis while EC-specific knockdown of Nrf2 results in the opposite effect. Pharmacological activators of endothelial Nrf2 may represent a novel therapeutic strategy for the treatment of atherosclerosis.


Subject(s)
Apolipoproteins E , Atherosclerosis , Endothelial Cells , Inflammation , Lipid Peroxidation , NF-E2-Related Factor 2 , Animals , Humans , Male , Mice , Apolipoproteins E/genetics , Apolipoproteins E/deficiency , Apolipoproteins E/metabolism , Atherosclerosis/metabolism , Atherosclerosis/genetics , Atherosclerosis/pathology , Disease Models, Animal , Endothelial Cells/metabolism , Inflammation/metabolism , Inflammation/genetics , Mice, Knockout , NF-E2-Related Factor 2/metabolism , NF-E2-Related Factor 2/genetics , Oxidative Stress
11.
Int J Surg Case Rep ; 120: 109871, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38852561

ABSTRACT

INTRODUCTION AND IMPORTANCE: Postoperative spontaneous spinal epidural hematoma (SSEDH) is a rare complication in clinical practice. Despite its rarity, SSEDH is a critical emergency situation associated with neurological deficits, and improper or delayed management may lead to severe consequences. Therefore, surgical operators should familiarize themselves with SSEDH and give it more attention. CASE PRESENTATION: This study describes the case of an elderly woman diagnosed with a left unilateral femoral neck fracture, severe osteoporosis, and multi-segmental vertebral compression fracture. Following artificial femoral head replacement surgery, the patient developed postoperative SSEDH. Subsequently, the patient underwent surgical removal of the posterior epidural hematoma and spinal cord decompression. The postoperative recovery was favorable, with normal muscle strength and tension in both lower limbs. A 4-year follow-up showed no complications. CLINICAL DISCUSSION: The occurrence of SSEDH during the perioperative period of non-spinal surgeries is relatively uncommon. However, SSEDH is a neurosurgical emergency associated with neurological deficits, and prompt surgical intervention is crucial for successful treatment. CONCLUSION: Clinicians should enhance their knowledge of SSEDH and remain vigilant towards this condition. Literature review highlights the significance of factors such as aging in the development of SSEDH following non-spinal surgeries in the perioperative period.

12.
Cell Death Dis ; 15(6): 434, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38898023

ABSTRACT

The interaction between glioblastoma cells and glioblastoma-associated macrophages (GAMs) influences the immunosuppressive tumor microenvironment, leading to ineffective immunotherapies. We hypothesized that disrupting the communication between tumors and macrophages would enhance the efficacy of immunotherapies. Transcriptomic analysis of recurrent glioblastoma specimens indicated an enhanced neuroinflammatory pathway, with CXCL12 emerging as the top-ranked gene in secretory molecules. Single-cell transcriptome profiling of naïve glioblastoma specimens revealed CXCL12 expression in tumor and myeloid clusters. An analysis of public glioblastoma datasets has confirmed the association of CXCL12 with disease and PD-L1 expression. In vitro studies have demonstrated that exogenous CXCL12 induces pro-tumorigenic characteristics in macrophage-like cells and upregulated PD-L1 expression through NF-κB signaling. We identified CXCR7, an atypical receptor for CXCL12 predominantly present in tumor cells, as a negative regulator of CXCL12 expression by interfering with extracellular signal-regulated kinase activation. CXCR7 knockdown in a glioblastoma mouse model resulted in worse survival outcomes, increased PD-L1 expression in GAMs, and reduced CD8+ T-cell infiltration compared with the control group. Ex vivo T-cell experiments demonstrated enhanced cytotoxicity against tumor cells with a selective CXCR7 agonist, VUF11207, reversing GAM-induced immunosuppression in a glioblastoma cell-macrophage-T-cell co-culture system. Notably, VUF11207 prolonged survival and potentiated the anti-tumor effect of the anti-PD-L1 antibody in glioblastoma-bearing mice. This effect was mitigated by an anti-CD8ß antibody, indicating the synergistic effect of VUF11207. In conclusion, CXCL12 conferred immunosuppression mediated by pro-tumorigenic and PD-L1-expressing GAMs in glioblastoma. Targeted activation of glioblastoma-derived CXCR7 inhibits CXCL12, thereby eliciting anti-tumor immunity and enhancing the efficacy of anti-PD-L1 antibodies.


Subject(s)
B7-H1 Antigen , Chemokine CXCL12 , Glioblastoma , Receptors, CXCR , Glioblastoma/pathology , Glioblastoma/immunology , Glioblastoma/genetics , Glioblastoma/metabolism , Humans , Animals , Receptors, CXCR/metabolism , Receptors, CXCR/genetics , Chemokine CXCL12/metabolism , Mice , B7-H1 Antigen/metabolism , Cell Line, Tumor , Tumor Microenvironment , Brain Neoplasms/pathology , Brain Neoplasms/immunology , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Signal Transduction/drug effects
13.
Appl Opt ; 63(14): 3785-3793, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38856341

ABSTRACT

In this paper, we have developed a 2D optical scanning module comprising cascaded 3D-printed one-axis rotating mirrors with large areas (30×30m m 2 for the X-direction scan and 60×25m m 2 for the Y-direction scan). Each mirror device contains a square or rectangular silicon substrate coated with aluminum, serving as the mirror. A 3D-printed structure, including the mirror frame (with four embedded mini permanent magnets on the backside), torsion springs, and base, is combined with the mirror; two electromagnets are situated under the mirror as the actuation mechanism. We apply DC voltage to the electromagnets to create magnetic force. The electromagnets can interact with the permanent magnets to make the mirror rotate. The X scan of the 2D scanning module can achieve a static optical scan angle of ∼11.8deg at the -X corners, and the corresponding Y-scan angle is ∼4.5deg, both with 12 VDC. Moreover, we have observed a fan-shaped distortion, a phenomenon not thoroughly studied previously for combining two single-axis scan mirrors. Therefore, we also perform a simulation to establish and demonstrate a correlation between the simulation prediction and experimental results. The 2D scanning module can be a low-cost alternative to the expensive conventional galvanometer scanners, and it can be used to upgrade a rangefinder to a simplified LiDAR.

14.
Front Pharmacol ; 15: 1389953, 2024.
Article in English | MEDLINE | ID: mdl-38828457

ABSTRACT

Cardiovascular disease (CVD) is a serious public health risk, and prevention and treatment efforts are urgently needed. Effective preventive and therapeutic programs for cardiovascular disease are still lacking, as the causes of CVD are varied and may be the result of a multifactorial combination. Mitophagy is a form of cell-selective autophagy, and there is increasing evidence that mitophagy is involved in cardioprotective processes. Recently, many studies have shown that FUN14 domain-containing protein 1 (FUNDC1) levels and phosphorylation status are highly associated with many diseases, including heart disease. Here, we review the structure and functions of FUNDC1 and the path-ways of its mediated mitophagy, and show that mitophagy can be effectively activated by dephosphorylation of Ser13 and Tyr18 sites, phosphorylation of Ser17 site and ubiquitination of Lys119 site in FUNDC1. By effectively activating or inhibiting excessive mitophagy, the quality of mitochondria can be effectively controlled. The main reason is that, on the one hand, improper clearance of mitochondria and accumulation of damaged mitochondria are avoided, and on the other hand, excessive mitophagy causing apoptosis is avoided, both serving to protect the heart. In addition, we explore the possible mechanisms by which FUNDC1-mediated mitophagy is involved in exercise preconditioning (EP) for cardioprotection. Finally, we also point out unresolved issues in FUNDC1 and its mediated mitophagy and give directions where further research may be needed.

15.
J Leukoc Biol ; 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38833591

ABSTRACT

Loss and overexpression of FAT1 occurs among different cancers with these divergent states equated with tumor suppressor and oncogene activity, respectively. Regarding the latter, FAT1 is highly expressed in a high proportion of human acute leukemias relative to normal blood cells, with evidence pointing to an oncogenic role. We hypothesized that this occurrence represents legacy expression of FAT1 in undefined hematopoietic precursor subsets that is sustained following transformation, predicating a role for FAT1 during normal hematopoiesis. We explored this concept by using the Vav-iCre strain to construct conditional knockout (cKO) mice where Fat1 expression was deleted at the hematopoietic stem cell stage. Extensive analysis of precursor and mature blood populations using multi-panel flow cytometry revealed no ostensible differences between Fat1 cKO mice and normal littermates. Further functional comparisons involving colony forming unit and competitive bone marrow transplantation assays support the conclusion that Fat1 is dispensable for normal murine hematopoiesis.

16.
Biomol Biomed ; 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38850114

ABSTRACT

Invasive lobular carcinoma (ILC) and invasive ductal carcinoma (IDC) account for most cases of breast cancer. However, there is ongoing debate about any potential variations in overall survival (OS) between ILC and IDC. This study aimed to compare survival between IDC and ILC, identify prognostic factors for ILC patients, and construct a nomogram for predicting OS rates. This retrospective cohort analysis utilized data from the Surveillance, Epidemiology, and End Results (SEER) Cancer Database. Patients diagnosed with ILC and IDC between 2000 and 2019 were enrolled. To minimize baseline differences in clinicopathological characteristics and survival outcomes, a propensity score matching (PSM) method was used. Data from the multivariate Cox regression analyses were used to construct a predictive nomogram for OS at 1, 3, and 5 years, incorporating all independent prognostic factors. Following the PSM procedure, patients with ILC exhibited a better prognosis compared to those with IDC. TNM stage, age >70, radiotherapy, surgery, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HR-/HER2+) subtype were identified as independent factors for OS in ILC patients. Surgery and radiotherapy effectively reduced the risk of death, while chemotherapy did not demonstrate the same benefit. This model could support clinicians in evaluating the prognosis of ILC for decision-making and patient counseling.

17.
Front Microbiol ; 15: 1410968, 2024.
Article in English | MEDLINE | ID: mdl-38873149

ABSTRACT

Introduction: Sweet sorghum juice is a typical production feedstock for natural, eco-friendly sweeteners and beverages. Clostridium tyrobutyricum is one of the widely used microorganisms in the food industry, and its principal product, bio-butyric acid is an important food additive. There are no published reports of Clostridium tyrobutyricum producing butyric acid using SSJ as the sole substrate without adding exogenous substances, which could reach a food-additive grade. This study focuses on tailoring a cost-effective, safe, and sustainable process and strategy for their production and application. Methods: This study modeled the enzymolysis of non-reducing sugars via the first/second-order kinetics and added food-grade diatomite to the hydrolysate. Qualitative and quantitative analysis were performed using high-performance liquid chromatography, gas chromatography-mass spectrometer, full-scale laser diffraction method, ultra-performance liquid chromatography-tandem mass spectrometry, the cell double-staining assay, transmission electron microscopy, and Oxford nanopore technology sequencing. Quantitative real-time polymerase chain reaction, pathway and process enrichment analysis, and homology modeling were conducted for mutant genes. Results: The treated sweet sorghum juice showed promising results, containing 70.60 g/L glucose and 63.09 g/L fructose, with a sucrose hydrolysis rate of 98.29% and a minimal sucrose loss rate of 0.87%. Furthermore, 99.62% of the colloidal particles and 82.13% of the starch particles were removed, and the concentrations of hazardous substances were effectively reduced. A food microorganism Clostridium tyrobutyricum TGL-A236 with deep utilization value was developed, which showed superior performance by converting 30.65% glucose and 37.22% fructose to 24.1364 g/L bio-butyric acid in a treated sweet sorghum juice (1:1 dilution) fermentation broth. This titer was 2.12 times higher than that of the original strain, with a butyric acid selectivity of 86.36%. Finally, the Genome atlas view, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and evolutionary genealogy of genes: Non-supervised Orthologous (eggNOG) functional annotations, three-dimensional structure and protein cavity prediction of five non-synonymous variant genes were obtained. Conclusion: This study not only includes a systematic process flow and in-depth elucidation of relevant mechanisms but also provides a new strategy for green processing of food raw materials, improving food microbial performance, and ensuring the safe production of food additives.

18.
Opt Express ; 32(8): 14674-14684, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38859405

ABSTRACT

Miniature acoustic sensors with high sensitivity are highly desired for applications in medical photoacoustic imaging, acoustic communications and industrial nondestructive testing. However, conventional acoustic sensors based on piezoelectric, piezoresistive and capacitive detectors usually require a large element size on a millimeter to centimeter scale to achieve a high sensitivity, greatly limiting their spatial resolution and the application in space-confined sensing scenarios. Herein, by using single-crystal two-dimensional gold flakes (2DGFs) as the sensing diaphragm of an extrinsic Fabry-Perot interferometer on a fiber tip, we demonstrate a miniature optical acoustic sensor with high sensitivity. Benefiting from the ultrathin thickness (∼8 nm) and high reflectivity of the 2DGF, the fiber-tip acoustic sensor gives an acoustic pressure sensitivity of ∼300 mV/Pa in the frequency range from 100 Hz to 20 kHz. The noise-equivalent pressure of the fiber-tip acoustic sensor at the frequency of 13 kHz is as low as 62.8 µPa/Hz1/2, which is one or two orders of magnitude lower than that of reported optical acoustic sensors with the same size.

19.
Opt Express ; 32(12): 21281-21292, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38859486

ABSTRACT

For weak coherent single-photon secure data communication among short-reach metropolitan intra-/inter-city networks at the O-band (1250-1350 nm), the commercially available semiconductor laser sources are emerging but still suffering from high single-mode-fiber (SMF) loss, broad linewidth, and unstable wavelength. To overcome such disadvantages for enabling the efficient phase-coding link with sufficient secure key rate, a specifically designed adiabatic package with active temperature-/current-feedback control is proposed for the paired O-band MHz-linewidth master-to-slave injection-locked DFBLDs and a polarization-maintaining 1-bit-delay interferometer is stabilized with using a passively adiabatic cell to achieve accurate differential phase decoding. Even though, the phonon-induced phase fluctuation still occurs at rising and falling edges of the decoded long-pattern secure data bits delivered from the slave DFBLD, which is mainly attributed to the intra-cavity heating under excessive free-carrier generation via the master DFBLD injection. To stabilize the differential-phase-shift (DPS) keying protocol, the phase-code distortion caused by over-injection-induced Auger heating is effectively suppressed by reducing the overly biased injection with precise master-injection-level control. The rising-/falling-edge damping distortion of the phase-shift-encoded secure bit-stream envelope is suppressed by appropriately decreasing the DC bias current and adjusting the AC encoding amplitude of the master DFBLD. Such operation reduces the incorrect π phase shift in the injection-locked slave DFBLD biased at optimized below-threshold DC offset, thus allowing single-photon DPS-keying data transmission over 15-km SMF with slightly increasing the single-photon bit-error ratio from <3% (0-km) to 6.2% (15-km).

20.
MedComm (2020) ; 5(7): e565, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38882210

ABSTRACT

Neuropeptide Y (NPY), a 36-amino-acid peptide, functions as a neurotransmitter in both the central and peripheral nervous systems by activating the NPY receptor subfamily. Notably, NPY analogs display varying selectivity and exert diverse physiological effects through their interactions with this receptor family. [Pro34]-NPY and [Leu31, Pro34]-NPY, mainly acting on Y1R, reportedly increases blood pressure and postsynaptically potentiates the effect of other vasoactive substances above all, while N-terminal cleaved NPY variants in human body primary mediates angiogenesis and neurotransmitter release inhibition through Y2R. However, the recognition mechanisms of Y1R and Y2R with specific agonists remain elusive, thereby hindering subtype receptor-selective drug development. In this study, we report three cryo-electron microscopy (cryo-EM) structures of Gi2-coupled Y1R and Y2R in complexes with NPY, as well as Y1R bound to a selective agonist [Leu31, Pro34]-NPY. Combined with cell-based assays, our study not only reveals the conserved peptide-binding mode of NPY receptors but also identifies an additional sub-pocket that confers ligand selectivity. Moreover, our analysis of Y1R evolutionary dynamics suggests that this sub-pocket has undergone functional adaptive evolution across different species. Collectively, our findings shed light on the molecular underpinnings of neuropeptide recognition and receptor activation, and they present a promising avenue for the design of selective drugs targeting the NPY receptor family.

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