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1.
Cell Rep ; 43(6): 114301, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38823016

ABSTRACT

CD8+ T cells are rendered exhausted in tumor and chronic infection. Among heterogeneous exhausted T cells, a subpopulation of progenitor-like (Tpex) cells have been found important for long-term tumor or pathogen control and are also the main responders in immunotherapy. Using an RFP reporter mouse for the orphan nuclear receptor NR4A1, originally characterized as critical in T cell dysfunction, we discover that the reporter is highly expressed in Tpex cells in tumor and chronic infection. Enforced expression of Nr4a1 promotes Tpex cell accumulation, whereas tumor control is improved after Nr4a1 deletion, associated with increased effector function but decreased long-term maintenance of CD8+ T cells. Integrating chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq) analysis, NR4A1 is found to bind and promote the expression of Tpex-related genes, as well as suppress terminal differentiation-associated genes. This study therefore has identified a key role of NR4A1 in Tpex regulation and provides a promising target for immunotherapy.

2.
J Autoimmun ; 147: 103259, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38823158

ABSTRACT

BACKGROUND: High salt intake may play a critical role in the etiology of psoriasis. Yet, evidence on the association of high salt intake with risk of psoriasis is limited. OBJECTIVE: To estimate the association between frequency of adding salt to foods and risk of psoriasis. METHODS: We conducted a prospective cohort study of 433,788 participants from the UK Biobank. Hazard ratios (HRs) and their 95 % confidence intervals (CIs) for risk of psoriasis in relation to frequency of adding salt to foods were estimated using multivariable Cox proportional hazards models. We further evaluated the joint association of adding salt to foods and genetic susceptibility with risk of psoriasis. We conducted a mediation analysis to assess how much of the effect of adding salt to foods on risk of psoriasis was mediated through several selected mediators. RESULTS: During a median of 14.0 years of follow-up, 4279 incident cases of psoriasis were identified. In the multivariable-adjusted model, a higher frequency of adding salt to foods was significantly associated with an increased risk of psoriasis ("always" versus "never/rarely" adding salt to foods, HR = 1.25, 95 % CI: 1.10, 1.41). The observed positive association was generally similar across subgroups. In the joint association analysis, we observed that participants with a high genetic risk (above the second tertile) and the highest frequency of adding salt to foods experienced 149 % higher risk of psoriasis, when compared with participants with a low genetic risk (below the first tertile) and the lowest frequency of adding salt to foods (HR = 2.49, 95 % CI: 2.05, 3.02). Mediation analysis revealed that 1.8 %-3.2 % of the positive association between frequency of adding salt and risk of psoriasis was statistically significantly mediated by obesity and inflammatory biomarkers such as C-reactive protein and systemic immune-inflammation index (all P values < 0.004). CONCLUSIONS: Our study demonstrated a positive association between frequency of adding salt to foods and risk of psoriasis. The positive association was independent of multiple other risk factors, and may be partially mediated through obesity and inflammation.

3.
Transl Psychiatry ; 14(1): 229, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38816410

ABSTRACT

Depression is a prevalent mental disorder with a complex biological mechanism. Following the rapid development of systems biology technology, a growing number of studies have applied proteomics and metabolomics to explore the molecular profiles of depression. However, a standardized resource facilitating the identification and annotation of the available knowledge from these scattered studies associated with depression is currently lacking. This study presents ProMENDA, an upgraded resource that provides a platform for manual annotation of candidate proteins and metabolites linked to depression. Following the establishment of the protein dataset and the update of the metabolite dataset, the ProMENDA database was developed as a major extension of its initial release. A multi-faceted annotation scheme was employed to provide comprehensive knowledge of the molecules and studies. A new web interface was also developed to improve the user experience. The ProMENDA database now contains 43,366 molecular entries, comprising 20,847 protein entries and 22,519 metabolite entries, which were manually curated from 1370 human, rat, mouse, and non-human primate studies. This represents a significant increase (more than 7-fold) in molecular entries compared to the initial release. To demonstrate the usage of ProMENDA, a case study identifying consistently reported proteins and metabolites in the brains of animal models of depression was presented. Overall, ProMENDA is a comprehensive resource that offers a panoramic view of proteomic and metabolomic knowledge in depression. ProMENDA is freely available at https://menda.cqmu.edu.cn .


Subject(s)
Depression , Metabolomics , Proteomics , Animals , Humans , Rats , Mice , Depression/metabolism , Brain/metabolism , Disease Models, Animal , Databases, Factual
4.
Sci Rep ; 14(1): 12188, 2024 05 28.
Article in English | MEDLINE | ID: mdl-38806640

ABSTRACT

Natural killer (NK) cells are closely associated with malignant tumor progression and metastasis. However, studies on their relevance in colorectal cancer (CRC) are limited. We aimed to comprehensively analyze the absolute counts, phenotypes, and function of circulating NK cells in patients with CRC using multiparametric flow cytometry. The distribution of NK cell subsets in the peripheral circulation of patients with CRC was significantly altered relative to the control group. This is shown by the decreased frequency and absolute count of CD56dimCD16+ NK cells with antitumor effects, contrary to the increased frequency of CD56bright NK and CD56dimCD16- NK cells with poor or ineffective antitumor effects. NK cells in patients with CRC were functionally impaired, with decreased intracellular interferon (IFN)-γ secretion and a significantly lower percentage of cell surface granzyme B and perforin expression. In addition, IFN-γ expression decreased significantly with the tumor stage progression. Based on a comprehensive analysis of the absolute counts, phenotypes, and functional markers of NK cells, we found an altered subset distribution and impaired function of circulating NK cells in patients with CRC.


Subject(s)
Colorectal Neoplasms , Granzymes , Interferon-gamma , Killer Cells, Natural , Humans , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Colorectal Neoplasms/immunology , Colorectal Neoplasms/pathology , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/blood , Male , Female , Middle Aged , Interferon-gamma/metabolism , Aged , Granzymes/metabolism , Perforin/metabolism , CD56 Antigen/metabolism , Flow Cytometry , Adult
5.
BMC Med Imaging ; 24(1): 126, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38807064

ABSTRACT

BACKGROUND: Automated Breast Ultrasound (AB US) has shown good application value and prospects in breast disease screening and diagnosis. The aim of the study was to explore the ability of AB US to detect and diagnose mammographically Breast Imaging Reporting and Data System (BI-RADS) category 4 microcalcifications. METHODS: 575 pathologically confirmed mammographically BI-RADS category 4 microcalcifications from January 2017 to June 2021 were included. All patients also completed AB US examinations. Based on the final pathological results, analyzed and summarized the AB US image features, and compared the evaluation results with mammography, to explore the detection and diagnostic ability of AB US for these suspicious microcalcifications. RESULTS: 250 were finally confirmed as malignant and 325 were benign. Mammographic findings including microcalcifications morphology (61/80 with amorphous, coarse heterogeneous and fine pleomorphic, 13/14 with fine-linear or branching), calcification distribution (189/346 with grouped, 40/67 with linear and segmental), associated features (70/96 with asymmetric shadow), higher BI-RADS category with 4B (88/120) and 4 C (73/38) showed higher incidence in malignant lesions, and were the independent factors associated with malignant microcalcifications. 477 (477/575, 83.0%) microcalcifications were detected by AB US, including 223 malignant and 254 benign, with a significantly higher detection rate for malignant lesions (x2 = 12.20, P < 0.001). Logistic regression analysis showed microcalcifications with architectural distortion (odds ratio [OR] = 0.30, P = 0.014), with amorphous, coarse heterogeneous and fine pleomorphic morphology (OR = 3.15, P = 0.037), grouped (OR = 1.90, P = 0.017), liner and segmental distribution (OR = 8.93, P = 0.004) were the independent factors which could affect the detectability of AB US for microcalcifications. In AB US, malignant calcification was more frequent in a mass (104/154) or intraductal (20/32), and with ductal changes (30/41) or architectural distortion (58/68), especially with the both (12/12). BI-RADS category results also showed that AB US had higher sensitivity to malignant calcification than mammography (64.8% vs. 46.8%). CONCLUSIONS: AB US has good detectability for mammographically BI-RADS category 4 microcalcifications, especially for malignant lesions. Malignant calcification is more common in a mass and intraductal in AB US, and tend to associated with architectural distortion or duct changes. Also, AB US has higher sensitivity than mammography to malignant microcalcification, which is expected to become an effective supplementary examination method for breast microcalcifications, especially in dense breasts.


Subject(s)
Breast Neoplasms , Calcinosis , Ultrasonography, Mammary , Humans , Calcinosis/diagnostic imaging , Female , Retrospective Studies , Middle Aged , Ultrasonography, Mammary/methods , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Adult , Aged , Mammography/methods , Aged, 80 and over
6.
Food Chem ; 455: 139902, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38820644

ABSTRACT

High-pressure homogenization modified quinoa protein (HQP) was added to porcine myofibrillar proteins (MP) to study its the influence on protein conformation, water distribution and dynamical rheological characteristics of low-salt porcine MP (0.3 M NaCl). Based on these results, the WHC, gel strength, and G' value of the low-salt MP gel were significantly improved with an increase in the added amount of HQP. A moderate amount of HQP (6%) increased the surface hydrophobicity and active sulfhydryl content of MP (P < 0.05). Moreover, the addition of HQP decreased particle size and endogenous fluorescence intensity. FT-IR results indicated that the conformation of α-helix gradually converted to ß-sheet by HQP addition. The incorporation of HQP also shortened the T2 relaxation time and enhanced the proportion of immobile water, contributing to the formation of a compact and homogeneous gel structure. In conclusion, the moderate addition of HQP can effectively enhance the structural stability and functionality of low-salt MP.

7.
Cell Rep ; 43(6): 114261, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38776224

ABSTRACT

Thymocyte development requires precise control of PI3K-Akt signaling to promote proliferation and prevent leukemia and autoimmune disorders. Here, we show that ablating individual clusters of the miR-17∼92 family has a negligible effect on thymocyte development, while deleting the entire family severely impairs thymocyte proliferation and reduces thymic cellularity, phenocopying genetic deletion of Dicer. Mechanistically, miR-17∼92 expression is induced by Myc-mediated pre-T cell receptor (TCR) signaling, and miR-17∼92 promotes thymocyte proliferation by suppressing the translation of Pten. Retroviral expression of miR-17∼92 restores the proliferation and differentiation of Myc-deficient thymocytes. Conversely, partial deletion of the miR-17∼92 family significantly delays Myc-driven leukemogenesis. Intriguingly, thymocyte-specific transgenic miR-17∼92 expression does not cause leukemia or lymphoma but instead aggravates skin inflammation, while ablation of the miR-17∼92 family ameliorates skin inflammation. This study reveals intricate roles of the miR-17∼92 family in balancing thymocyte development, leukemogenesis, and autoimmunity and identifies those microRNAs (miRNAs) as potential therapeutic targets for leukemia and autoimmune diseases.

8.
Adv Mater ; : e2402309, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38780003

ABSTRACT

Soft materials play a crucial role in small-scale robotic applications by closely mimicking the complex motion and morphing behavior of organisms. However, conventional fabrication methods face challenges in creating highly integrated small-scale soft devices. In this study, we leverage microfluidics to precisely control reaction-diffusion (RD) processes to generate multifunctional and compartmentalized calcium-cross-linkable alginate-based microfibers. Under RD conditions, we produce sophisticated alginate-based fibers for magnetic soft continuum robotics (mSCR) applications with customizable features, such as geometry (compact or hollow), degree of cross-linking, and the precise localization of magnetic nanoparticles (inside the core, surrounding the fiber, or on one side). This fine control allows for tuning the stiffness and magnetic responsiveness of the microfibers. Additionally, chemically cleavable regions within the fibers enable disassembly into smaller robotic units or roll-up structures under a rotating magnetic field. These findings demonstrate the versatility of microfluidics in processing highly integrated small-scale devices. This article is protected by copyright. All rights reserved.

9.
Mol Neurobiol ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38722514

ABSTRACT

Major depressive disorder (MDD) is a severe mental illness characterized by a lack of objective biomarkers. Mounting evidence suggests there are extensive transcriptional molecular changes in the prefrontal cortex (PFC) of individuals with MDD. However, it remains unclear whether there are specific genes that are consistently altered and possess diagnostic power. In this study, we conducted a systematic search of PFC datasets of MDD patients from the Gene Expression Omnibus database. We calculated the differential expression of genes (DEGs) and identified robust DEGs using the RRA and MetaDE methods. Furthermore, we validated the consistently altered genes and assessed their diagnostic power through enzyme-linked immunosorbent assay experiments in our clinical blood cohort. Additionally, we evaluated the diagnostic power of hub DEGs in independent public blood datasets. We obtained eight PFC datasets, comprising 158 MDD patients and 263 healthy controls, and identified a total of 1468 unique DEGs. Through integrated analysis, we identified 290 robustly altered DEGs. Among these, seven hub DEGs (SLC1A3, PON2, AQP1, EFEMP1, GJA1, CENPD, HSD11B1) were significantly down-regulated at the protein level in our clinical blood cohort. Moreover, these hub DEGs exhibited a negative correlation with the Hamilton Depression Scale score (P < 0.05). Furthermore, these hub DEGs formed a panel with promising diagnostic power in three independent public blood datasets (average AUCs of 0.85) and our clinical blood cohort (AUC of 0.92). The biomarker panel composed of these genes demonstrated promising diagnostic efficacy for MDD and serves as a useful tool for its diagnosis.

10.
Plant J ; 2024 May 13.
Article in English | MEDLINE | ID: mdl-38739690

ABSTRACT

Several dwarf and semi-dwarf genes have been identified in barley. However, only a limited number have been effectively utilized in breeding programs to cultivate lodging resistant varieties. This is due to the common association of dwarf and semi-dwarf traits with negative effects on malt quality. In this study, we employed gene editing to generate three new haplotypes of sdw1/denso candidate gene gibberellin (GA) 20-oxidase2 (GA20ox2). These haplotypes induced a dwarfing phenotype and enhancing yield potential, and promoting seed dormancy, thereby reducing pre-harvest sprouting. Moreover, ß-amylase activity in the grains of the mutant lines was significantly increased, which is beneficial for malt quality. The haplotype analysis revealed significant genetic divergence of this gene during barley domestication and selection. A novel allele (sdw1.ZU9), containing a 96-bp fragment in the promoter region of HvGA20ox2, was discovered and primarily observed in East Asian and Russian barley varieties. The 96-bp fragment was associated with lower gene expression, leading to lower plant height but higher germination rate. In conclusion, HvGA20ox2 can be potentially used to develop semi-dwarf barley cultivars with high yield and improved malt quality.

11.
ACS Appl Mater Interfaces ; 16(20): 26713-26732, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38723291

ABSTRACT

To solve the problem of ice condensation and adhesion, it is urgent to develop new anti-icing and deicing technologies. This study presented the development of a highly efficient photothermal-enhanced superhydrophobic PDMS/Ni@Ti3C2Tx composite film (m-NMPA) fabricated cost-effectively and straightforwardly. This film was fabricated utilizing PDMS as a hydrophobic agent, adhesive, and surface protector, while Ni@Ti3C2Tx as a magnetic photothermal filler innovatively. Through a simple spraying method, the filler is guided by a strong magnetic field to self-assemble into an eyelash-like microstructure array. The unique structure not only imparts superhydrophobic properties to the surface but also constructs an efficient "light-capturing" architecture. Remarkably, the m-NMPA film demonstrates outstanding superhydrophobic passive anti-icing and efficient photothermal active deicing performance without the use of fluorinated chemicals. The micro-/nanostructure of the film forms a gas layer, significantly delaying the freezing time of water. Particularly under extreme cold conditions (-30 °C), the freezing time is extended by a factor of 7.3 compared to the bare substrate. Furthermore, under sunlight exposure, surface droplets do not freeze. The excellent photothermal performance is attributed to the firm anchoring of nickel particles on the MXene surface, facilitating effective "point-to-face" photothermal synergy. The eyelash-like microarray structure enhances light-capturing capability, resulting in a high light absorption rate of 98%. Furthermore, the microstructure aids in maintaining heat at the uppermost layer of the surface, maximizing the utilization of thermal energy for ice melting and frost thawing. Under solar irradiation, the m-NMPA film can rapidly melt approximately a 4 mm thick ice layer within 558 s and expel the melted water promptly, reducing the risk of secondary icing. Additionally, the ice adhesion force on the surface of the m-NMPA film is remarkably low, with an adhesion strength of approximately 4.7 kPa for a 1 × 1 cm2 ice column. After undergoing rigorous durability tests, including xenon lamp weathering test, pressure resistance test, repeated adhesive tape testing, xenon lamp irradiation, water drop impact testing, and repeated brushing with hydrochloric acid and particles, the film's surface structure and superhydrophobic performance have remained exceptional. The photothermal superhydrophobic passive anti-icing and active deicing technology in this work rely on sustainable solar energy for efficient heat generation. It presents broad prospects for practical applications with advantages such as simple processing method, environmental friendliness, outstanding anti-icing effects, and exceptional durability.

12.
Skin Res Technol ; 30(5): e13720, 2024 May.
Article in English | MEDLINE | ID: mdl-38743384

ABSTRACT

BACKGROUND: Sensitive skin is hypersensitive to various external stimuli and a defective epidermal permeability barrier is an important clinical feature of sensitive skin. Claudin-5 (CLDN5) expression levels decrease in sensitive skin. This study aimed to explore the impact of CLDN5 deficiency on the permeability barrier in sensitive skin and the regulatory role of miRNAs in CLDN5 expression. MATERIALS AND METHODS: A total of 26 patients were retrospectively enrolled, and the CLDN5 expression and permeability barrier dysfunction in vitro were assessed. Then miRNA-224-5p expression was also assessed in sensitive skin. RESULTS: Immunofluorescence and electron microscopy revealed reduced CLDN5 expression, increased miR-224-5p expression, and disrupted intercellular junctions in sensitive skin. CLDN5 knockdown was associated with lower transepithelial electrical resistance (TEER) and Lucifer yellow penetration in keratinocytes and organotypic skin models. The RNA-seq and qRT-PCR results indicated elevated miR-224-5p expression in sensitive skin; MiR-224-5p directly interacted with the 3`UTR of CLDN5, resulting in CLDN5 deficiency in the luciferase reporter assay. Finally, miR-224-5p reduced TEER in keratinocyte cultures. CONCLUSION: These results suggest that the miR-224-5p-induced reduction in CLDN5 expression leads to impaired permeability barrier function, and that miR-224-5p could be a potential therapeutic target for sensitive skin.


Subject(s)
Claudin-5 , Keratinocytes , MicroRNAs , Permeability , Humans , MicroRNAs/metabolism , MicroRNAs/genetics , Claudin-5/genetics , Claudin-5/metabolism , Female , Male , Keratinocytes/metabolism , Retrospective Studies , Adult , Skin/metabolism
13.
Front Pharmacol ; 15: 1341039, 2024.
Article in English | MEDLINE | ID: mdl-38711992

ABSTRACT

Background: Gastric cancer (GC) is one of the major malignancies threatening human lives and health. Non-SMC condensin II complex subunit D3 (NCAPD3) plays a crucial role in the occurrence of many diseases. However, its role in GC remains unexplored. Materials and Methods: The Cancer Genome Atlas (TCGA) database, clinical samples, and cell lines were used to analyze NCAPD3 expression in GC. NCAPD3 was overexpressed and inhibited by lentiviral vectors and the CRISPR/Cas9 system, respectively. The biological functions of NCAPD3 were investigated in vitro and in vivo. Gene microarray, Gene set enrichment analysis (GSEA) and ingenuity pathway analysis (IPA) were performed to establish the potential mechanisms. Results: NCAPD3 was highly expressed in GC and was associated with a poor prognosis. NCAPD3 upregulation significantly promoted the malignant biological behaviors of gastric cancer cell, while NCAPD3 inhibition exerted a opposite effect. NCAPD3 loss can directly inhibit CCND1 and ESR1 expression to downregulate the expression of downstream targets CDK6 and IRS1 and inhibit the proliferation of gastric cancer cells. Moreover, NCAPD3 loss activates IRF7 and DDIT3 to regulate apoptosis in gastric cancer cells. Conclusion: Our study revealed that NCAPD3 silencing attenuates malignant phenotypes of GC and that it is a potential target for GC treatment.

14.
Front Endocrinol (Lausanne) ; 15: 1413519, 2024.
Article in English | MEDLINE | ID: mdl-38706695

ABSTRACT

[This corrects the article DOI: 10.3389/fendo.2024.1294638.].

16.
Cell Prolif ; : e13679, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38801100

ABSTRACT

Uncovering mechanisms of endogenous regeneration and repair through resident stem cell activation will allow us to develop specific therapies for injuries and diseases by targeting resident stem cell lineages. Sox9+ stem cells have been reported to play an essential role in acute kidney injury (AKI). However, a complete view of the Sox9+ lineage was not well investigated to accurately elucidate the functional end state and the choice of cell fate during tissue repair after AKI. To identify the mechanisms of fate determination of Sox9+ stem cells, we set up an AKI model with prostaglandin E2 (PGE2) treatment in a Sox9 lineage tracing mouse model. Single-cell RNA sequencing (scRNA-seq) was performed to analyse the transcriptomic profile of the Sox9+ lineage. Our results revealed that PGE2 could activate renal Sox9+ cells and promote the differentiation of Sox9+ cells into renal proximal tubular epithelial cells and inhibit the development of fibrosis. Furthermore, single-cell transcriptome analysis demonstrated that PGE2 could regulate the restoration of lipid metabolism homeostasis in proximal tubular epithelial cells by participating in communication with different cell types. Our results highlight the prospects for the activation of endogenous renal Sox9+ stem cells with PGE2 for the regenerative therapy of AKI.

18.
J Chem Phys ; 160(20)2024 May 28.
Article in English | MEDLINE | ID: mdl-38804489

ABSTRACT

The thermophysical properties and elemental abundances of the noble gases in terrestrial materials can provide unique insights into the Earth's evolution and mantle dynamics. Here, we perform extensive ab initio molecular dynamics simulations to determine the melting temperature and sound velocity of neon up to 370 GPa and 7500 K to constrain its physical state and storage capacity, together with to reveal its implications for the deep interior of the Earth. It is found that solid neon can exist stably under the lower mantle and inner core conditions, and the abnormal melting of neon is not observed under the entire temperature (T) and pressure (P) region inside the Earth owing to its peculiar electronic structure, which is substantially distinct from other heavier noble gases. An inspection of the reduction for sound velocity along the Earth's geotherm evidences that neon can be used as a light element to account for the low-velocity anomaly and density deficit in the deep Earth. A comparison of the pair distribution functions and mean square displacements of MgSiO3-Ne and Fe-Ne alloys further reveals that MgSiO3 has a larger neon storage capacity than the liquid iron under the deep Earth condition, indicating that the lower mantle may be a natural deep noble gas storage reservoir. Our results provide valuable information for studying the fundamental behavior and phase transition of neon in a higher T-P regime, and further enhance our understanding for the interior structure and evolution processes inside the Earth.

19.
Animals (Basel) ; 14(10)2024 May 17.
Article in English | MEDLINE | ID: mdl-38791709

ABSTRACT

The composition and metabolic profile of the ruminal microbiome have an impact on milk composition. To unravel the ruminal microbiome and metabolome affecting milk fat synthesis in dairy cows, 16S rRNA and internal transcribed spacer (ITS) gene sequencing, as well as ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS) methods were used to investigate the significant differences in ruminal bacterial and fungal communities as well as metabolome among Chinese Holstein cows with contrasting milk fat contents under the same diet (H-MF 5.82 ± 0.41% vs. L-MF 3.60 ± 0.12%). Another objective was to culture bovine mammary epithelial cells (BMECs) to assess the effect of metabolites on lipid metabolism. Results showed that the acetate-to-propionate ratio and xylanase activity in ruminal fluid were both higher in H-MF. Microbiome sequencing identified 10 types of bacteria and four types of fungi differently abundant at the genus level. Metabolomics analysis indicated 11 different ruminal metabolites between the two groups, the majority of which were lipids and organic acids. Among these, lauric acid (LA) was enriched in fatty acid biosynthesis with its concentration in milk fat of H-MF cows being greater (217 vs. 156 mg per 100 g milk), thus, it was selected for an in vitro study with BMECs. Exogenous LA led to a marked increase in intracellular triglyceride (TG) content and lipid droplet formation, and it upregulated the mRNA abundance of fatty acid uptake and activation (CD36 and ACSL1), TG synthesis (DGAT1, DGAT2 and GPAM), and transcriptional regulation (SREBP1) genes. Taken together, the greater relative abundance of xylan-fermenting bacteria and fungi, and lower abundance of bacteria suppressing short-chain fatty acid-producing bacteria or participating in fatty acid hydrogenation altered lipids and organic acids in the rumen of dairy cows. In BMECs, LA altered the expression of genes involved in lipid metabolism in mammary cells, ultimately promoting milk fat synthesis. Thus, it appears that this fatty acid plays a key role in milk fat synthesis.

20.
Anal Chem ; 96(21): 8416-8423, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38755966

ABSTRACT

Nanogap-based plasmonic metal nanocrystals have been applied in surface-enhanced Raman scattering detection, while the closed and insufficient electromagnetic fields as well as the nonreproducible Raman signal of the substrate greatly restrict the actual application. Herein, a highly uniform Au/AgAu monolayer with abundant nanogaps and huge electromagnetic enhancement is prepared, which shows ultrasensitive and reproducible SERS detection. Au/AgAu with an inner nanogap is first prepared based on Au nanotriangles, and the nanogap is opened from the three tips via a subsequent etching process. The open-gap Au/AgAu displays much higher SERS efficiency than Au and Au/AgAu with an inner nanogap on detecting crystal violet due to the open-gap induced electromagnetic enhancement and improved molecular absorption. Furthermore, the open-gap Au/AgAu monolayer is prepared via interfacial self-assembly, which shows further improved SERS due to the dense and strong hotspots in the nanocavities induced by the electromagnetic coupling between adjacent open gaps. The monolayer possesses excellent signal stability, uniformity, and reproducibility. The analytic enhancement factor and relative standard deviation reach to 2.12 × 108 and 4.65% on detecting crystal violet, respectively. Moreover, the monolayer achieves efficient detection of thiram in apple juice, biphenyl-4-thiol, 4-mercaptobenzoic, melamine, and a mixed solution of four different molecules, showing great promise in practical detection.

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