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1.
Microbiome ; 10(1): 76, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35546409

RESUMO

Although there is now an extensive understanding of the diversity of microbial life on earth through culture-independent metagenomic DNA sequence analyses, the isolation and cultivation of microbes remains critical to directly study them and confirm their metabolic and physiological functions, and their ecological roles. The majority of environmental microbes are as yet uncultured however; therefore, bringing these rare or poorly characterized groups into culture is a priority to further understand microbiome functions. Moreover, cultivated isolates may find utility in a range of applications, such as new probiotics, biocontrol agents, and agents for industrial processes. The growing abundance of metagenomic and meta-transcriptomic sequence information from a wide range of environments provides more opportunities to guide the isolation and cultivation of microbes of interest. In this paper, we discuss a range of successful methodologies and applications that have underpinned recent metagenome-guided isolation and cultivation of microbe efforts. These approaches include determining specific culture conditions to enrich for taxa of interest, to more complex strategies that specifically target the capture of microbial species through antibody engineering and genome editing strategies. With the greater degree of genomic information now available from uncultivated members, such as via metagenome-assembled genomes, the theoretical understanding of their cultivation requirements will enable greater possibilities to capture these and ultimately gain a more comprehensive understanding of the microbiomes. Video Abstract.

2.
Front Public Health ; 10: 878161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35570934

RESUMO

Human adenovirus (HAdV) is a common virus, but the infections it causes are relatively uncommon. At the same time, the methods for the detection of HAdV are varied, among which viral culture is still the gold standard. HAdV infection is usually self-limited but can also cause clinically symptomatic in lots of organs and tissues, of which human adenovirus pneumonia is the most common. In contrast, human adenovirus hepatitis is rarely reported. However, HAdV hepatitis has a high fatality rate once it occurs, especially in immunocompromised patients. Although human adenovirus hepatitis has some pathological and imaging features, its clinical symptoms are not typical. Therefore, HAdV hepatitis is not easy to be found in the clinic. There are kinds of treatments to treat this disease, but few are absolutely effective. In view of the above reasons, HAdV hepatitis is a disease that is difficult to be found in time. We reviewed and summarized the previously reported cases, hoping to bring some relatively common characteristics to clinicians, so as to facilitate early detection, early diagnosis, and early treatment of patients.

3.
Anim Nutr ; 9: 175-183, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35573096

RESUMO

Total milk solid (TMS) content directly reflects the quality of milk. Rumen bacteria ferment dietary components, the process of which generates the precursors for the synthesis of milk solid, therefore, the variation in rumen bacterial community could be associated with milk solid in dairy cows. In this study, 45 healthy mid-lactation Holstein dairy cows with the similar body weight, lactation stage, and milk yield were initially used for the selection of 10 cows with high TMS (HS) and 10 cows with low TMS (LS). All those animals were under the same feeding management, and the individual milk yield was recorded for 14 consecutive days before milk and rumen fluid were sampled. Rumen fluid was used to determine bacterial community by 16S rRNA gene sequencing technique. The HS cows had significantly greater feed intake and milk TMS, fat, protein content than LS cows (P < 0.05). Among the volatile fatty acids (VFA), propionic acid and valeric acid concentrations were significantly greater in HS cows than those in LS cows (P < 0.05). There was no significant difference in the concentrations of acetate, butyrate, isobutyrate, valerate, and the total VFA (P > 0.05), nor was the acetate-to-propionate ratio, pH value, ammonia nitrogen and microbial crude protein concentrations (P > 0.05). Significant differences in the relative abundances of some bacterial genera were found between HS and LS cows. Spearman's rank correlation analysis revealed that TMS content was correlated positively with the abundances of Ruminococcaceae UCG-014, Ruminococcaceae NK4A214 group, Prevotellaceae UCG-001, Butyrivibrio 2, Prevotellaceae UCG-003, Candidatus Saccharimonas, Ruminococcus 2, Lachnospiraceae XPB1014 group, probable genus 10, Eubacterium ventriosum group, but negatively correlated with Pyramidobacte. In addition, Ruminococcaceae UCG-014, Ruminococcus 2, Ruminococcaceae UCG001, probable genus 10 and Eubacterium ventriosum group might boost the total VFA production in the rumen. In conclusion, the dry matter intake of dairy cows and some special bacteria in rumen were significantly associated with TMS content, which suggests the potential function of rumen bacteria contributing to TMS content in dairy cows.

4.
Small ; : e2200646, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35510984

RESUMO

Photothermal therapy (PTT) as a noninvasive hyperthermia exhibits high potential for anti-cancer treatments. The explosion of efficient photothermal agents (PTAs) keeps developing rapidly. MXene stands out due to its intriguing structures, fantastic photodynamic properties, and good biocompatibility. However, the potential of MXenes has not been sufficiently explored in PTT. Its versatile chemical compositions of MXenes provide vast opportunities to discover new candidates. Considering that the metallic feature is mainly attributed to the metal element, anionic modulation may open a distinct avenue to propel efficient PTAs with metallic nature, which is expected for high light-harvesting over near-infrared (NIR)-I and NIR-II. As a paradigm, metal carbonitride is chosen to visualize the influences of anionic modulation. Taking advantage of electron injection from nitrogen, the distinct carbonitride Ti3 C1.15 N0.85 F0.88 O0.56 (OH)0.56 exhibits a strong NIR absorption (36.6 L g-1 cm-1 at 808 nm, 43.5 L g-1 cm-1 at 1064 nm), resulting in efficient photonic hyperthermia against tumors in vitro and in vivo. Looking through a large family of MXenes, this proof-of-principle demonstration offers a deep understanding between atomic composition and physicochemical properties, which further solidifies MXenes with all the potential for biomedical applications.

5.
J Colloid Interface Sci ; 622: 169-180, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35490620

RESUMO

The solar-driven interfacial evaporation (SDIE) is now a promising way to solve the shortage of fresh water. However, high performance SDIE for the oil contaminated seawater remains challenging. Here, we propose a facile "chitosan assisted MXene decoration" strategy to prepare a superhydrophilic and underwater superoleophobic Chitosan/MXene/fabric (CMF) for highly efficient SDIE. Benefiting from the superhydrophilicity and excellent photo-thermal conversion performance, the CMF is served as both the solar absorber and the water transportation path. Under the light illumination with one sun intensity (1 kW·m-2), a high evaporation rate of 1.50 kg·m-2·h-1 and efficiency of 88.05% are achieved. The strong interfacial interaction and outstanding salt rejection behavior of the CMF ensure the SDIE long-term stability and durability. In addition, the underwater superoleophobic CMF can effectively and quickly repel different oils and is hence suitable for high performance SDIE of the oil-in-water emulsion and the crude oil contaminated seawater. This work provides a rational design and optimization for the SDIE system, which holds great potential in practical desalination applications.

6.
Eur J Pharmacol ; 925: 174987, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35490726

RESUMO

BACKGROUND: Ischemic stroke is one of the leading causes of mortality worldwide. The available treatments are not effective. Phosphodiesterase 9A (PDE9A) is an intracellular cyclic guanosine monophosphate (cGMP) hydrolase considered to be a promising therapeutic target for brain diseases. This study explored neuroprotective effects and the underlying mechanism of LW33, a novel PDE9A inhibitor, on ischemic stroke in vitro and in vivo. METHODS: A middle cerebral artery occlusion (MCAO) model was established in adult male Sprague-Dawley rats and an oxygen-glucose deprivation/reoxygenation (OGD/R) model was established in human SH-SY5Y cells to mimic ischemia-reperfusion injury in vitro. RESULTS: LW33 increased cell viability, reduced lactate dehydrogenase activity, and OGD/R-induced apoptosis of SH-SY5Y cells. The protective effects of LW33 against stroke occurred in the recovery phase. LW33 administration significantly reduced cerebral infarction volume in MCAO rats, without causing significant deformation or necrosis of neurons in the cortex. LW33 also improved learning and cognitive dysfunction and reduced other pathological changes in MCAO rats in the recovery period. Moreover, LW33 stimulated the cGMP/PKG/CREB pathway and up-regulated the expression of the apoptosis-related proteins, and this effect was reversed by KT5823 treatment. CONCLUSION: LW33 inhibited cell apoptosis and promoted neuronal repair to alleviate OGD/R and MCAO induced pathological alterations via the cGMP/PKG/CREB pathway, indicating that LW33 may be a promising therapeutic target for ischemic stroke.

7.
Foods ; 11(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35563935

RESUMO

Alkaline phosphatase (ALP) is abundant in raw milk. Because of its high heat resistance, ALP negative is used as an indicator of successful sterilization. However, pasteurized milk loses its immune protection against allergy. Clinically, ALP is also used as an indicator of organ diseases. When the activity of ALP in blood increases, it is considered that diseases occur in viscera and organs. Oral administration or injecting ALP will not cause harm to the body and has a variety of probiotic effects. For infants with low immunity, ALP intake is a good prebiotic for protecting the infant's intestine from potential pathogenic bacteria. In addition, ALP has a variety of probiotic effects for any age group, including prevention and treatment intestinal diseases, allergies, hepatitis, acute kidney injury (AKI), diabetes, and even the prevention of aging. The prebiotic effects of alkaline phosphatase on the health of infants and consumers and the content of ALP in different mammalian raw milk are summarized. The review calls on consumers and manufacturers to pay more attention to ALP, especially for infants with incomplete immune development. ALP supplementation is conducive to the healthy growth of infants.

8.
Front Nutr ; 9: 845150, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35578614

RESUMO

Milk is rich in fat, protein, minerals, vitamins, peptides, immunologically active substances, and other nutrients, and it plays an important role in satisfying human nutrition and health. However, dairy product safety incidents caused by microbial contamination have occurred. We found that the total bacterial numbers in the pasteurized product were low and far below the limit requirements of the food safety standards of the European Union, the United States, and China. At the genus level, the primary microbial groups found in milk samples were Acinetobacter, Macrococcus, Pseudomonas, and Lactococcus, while in the equipment rinse water and air samples there was contamination by Stenotrophomonas and Acinetobacter. The Source Tracker model analysis indicated that the microorganisms in the final milk products were significantly related to the contamination in product tanks and raw milk. Therefore, it is the hope that this work can provide guidance to pinpoint contamination problems using the proper quality control sampling at specific stages in the pasteurization process.

9.
Adv Mater ; : e2201413, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35419852

RESUMO

The abilities to generate and manipulate photoluminescence (PL) with high spatial resolution have been of primary importance for applications in micro-optoelectronics, while the emerging metal halide perovskites offer novel material platforms where diverse photonic functionalities and fine structuring are constantly explored. Herein, micro-PL patterns consisting of highly luminescent CsPbBr3 nanocrystals (NCs) in non-luminescent perovskite crystals are directly fabricated by focused femtosecond laser irradiation. The further modulation with a moisture field leads to the selective dissolution of the laser-destabilized perovskite structures as density functional theory simulations revealed, thus allowing for facile control of the reversible PL from the recrystallization of the CsPbBr3 NCs. By leveraging the coupled laser writing and moisture modulation, multimodal information encryption is realized by reversible encryption-reading and repeatable erasing-refreshing. This optical storage mechanism is also extended to three-dimensional and four-dimensional by realizing spatially and temporally resolved optical encryption. The coupled multi-field modulation on perovskite crystals could enable potential applications in optical storage and encryption, and offer a novel solution for the creation and manipulation of localized PL structures with high temporal and spatial resolutions. This article is protected by copyright. All rights reserved.

10.
Front Neurosci ; 16: 847180, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431778

RESUMO

In a gesture recognition system based on surface electromyogram (sEMG) signals, the recognition model established by existing users cannot directly generalize to the across-user scenarios due to the individual variability of sEMG signals. In this article, we propose an adaptive learning method to handle the problem. The muscle synergy is chosen as the feature vector because it can well-characterize the neural origin of movement. The initial train set is composed of representative samples extracted from the synergy matrix of the existing user. When the new users use the system, the label is obtained by the adaptive K nearest neighbor algorithm (KNN). The recognition process does not require the pre-experiment for new users due to the introduction of adaptive learning strategy, namely, the qualified data and the label of new user data evaluated by a risk evaluator are used to update the train set and KNN weights, so as to adapt to the new users. We have tested the algorithm in DB1 and DB5 of Ninapro databases. The average recognition accuracy is 68.04, 73.35, and 83.05% for different types of gestures, respectively, achieving the effects of the user-dependent method. Our study can avoid the re-training steps and the recognition performance will improve with the increased frequency of uses, which will further facilitate the widespread implementation of sEMG control systems using pattern recognition techniques.

11.
J Environ Sci (China) ; 114: 465-474, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35459509

RESUMO

Sediment is recognized as the largest reservoir and source of methane (CH4) in the ocean, especially in the shallow coastal areas. To date, few data of CH4 concentration in sediment have been reported in the China shelf seas. In this study, we measured CH4 concentration in sediment and overlying seawater columns, and conducted an incubation experiment in the Bohai Sea in May 2017. CH4 concentration was found to be ranged from 3.075 to 1.795 µmol/L in sediment, which was 2 to 3 orders of magnitude higher than that in overlying seawater columns. The surface sediment was an important source of CH4, while bottom seawater acted as its sink. Furthermore, the net emission rate via sediment water interface (SWI) was calculated as 2.45 µmol/(m2∙day) based on the incubation experiment at station 73, and the earthquake may enhance CH4 release from sediment to seawater column in the eastern Bohai Sea.


Assuntos
Metano , Poluentes Químicos da Água , China , Monitoramento Ambiental , Metano/análise , Oceanos e Mares , Água do Mar , Água , Poluentes Químicos da Água/análise
12.
Front Endocrinol (Lausanne) ; 13: 806807, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35321336

RESUMO

Objective: To explore the association between serum leucine (leu) and diabetic retinopathy (DR) in patients with type 2 diabetes (T2D) and then to analyze the influence of gender on the association. Method: The electronic medical records of 1,149 T2D patients who met inclusion and exclusion criteria were retrieved from the Second Affiliated Hospital of Dalian Medical University and the First Affiliated Hospital of Jinzhou Medical University. Serum leu levels of all subjects were measured by liquid chromatography-mass spectrometry. Logistic regression was used to obtain the odds ratio (OR) and CI of leu-DR risk in multiple models. When using these models, restricted cubic spline (RCS) was used to test the potential non-linear relationship between multiple continuous independent variables, such as leu and DR (classification), and dependent variables. We also used the additive interaction method to evaluate the interaction effect between leu and gender on DR. Results: Leu was a protective factor of DR [0.78 (0.66, 0.92)]. When gender was divided into male and female, the above relationship was statistically significant only in men [0.73 (0.58, 0.94)]. Three indicators of additive interaction-RERI, AP, and S-suggested that there is no interaction between gender and leu on the risk of DR. Conclusions: Male T2D patients with high leu levels may have a lower risk of DR.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , China/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/etiologia , Feminino , Humanos , Leucina , Modelos Logísticos , Masculino
13.
Toxins (Basel) ; 14(3)2022 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-35324670

RESUMO

Aflatoxin M1 (AFM1) and ochratoxin A (OTA), which are occasionally detected in milk and commercial baby foods, could easily enter and reach the gastrointestinal tract, posing impairment to the first line of defense and causing dysfunction of the tissue. The objective of this study was to investigate the immunostimulatory roles of individual and combined AFM1 and OTA on the immature intestine. Thus, we used ELISA assays to evaluate the generation of cytokines from ex vivo CD-1 fetal mouse jejunum induced by AFM1 and OTA and explored the related regulatory pathways and pivot genes using RNA-seq analysis. It was found that OTA exhibited much stronger ability in stimulating pro-inflammatory cytokine IL-6 from jejunum tissues than AFM1 (OTA of 4 µM versus AFM1 of 50 µM), whereas the combination of the two toxins seemed to exert antagonistic actions. In addition, transcriptomics also showed that most gene members in the enriched pathway 'cytokine-cytokine receptor interaction' were more highly expressed in OTA than the AFM1 group. By means of PPI network analysis, NFKB1 and RelB were regarded as hub genes in response to OTA but not AFM1. In the human FHs 74 Int cell line, both AFM1 and OTA enhanced the content of reactive oxygen species, and the oxidative response was more apparent in OTA-treated cells in comparison with AFM1. Furthermore, OTA and AFM1 + OTA raised the protein abundance of p50/RelB, and triggered the translocation of the dimer from cytosol to nucleus. Therefore, the experimental data ex vivo and in vitro showed that OTA-induced inflammation was thought to be bound up with the up-regulation and translocation of NF-κB, though AFM1 seemed to have no obvious impact. Since it was the first attempt to uncover the appearances and inner mechanisms regarding inflammation provoked by AFM1 and OTA on immature intestinal models, further efforts are needed to understand the detailed metabolic steps of the toxin in cells and to clarify their causal relationship with the signals proposed from current research.


Assuntos
Aflatoxina M1 , Intestinos , Aflatoxina M1/análise , Animais , Citocinas/genética , Contaminação de Alimentos/análise , Inflamação/induzido quimicamente , Intestinos/química , Camundongos , Leite/química , Ocratoxinas
14.
Neurophotonics ; 9(3): 032207, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35355658

RESUMO

Neuromodulation poses an invaluable role in deciphering neural circuits and exploring clinical treatment of neurological diseases. Optoacoustic neuromodulation is an emerging modality benefiting from the merits of ultrasound with high penetration depth as well as the merits of photons with high spatial precision. We summarize recent development in a variety of optoacoustic platforms for neural modulation, including fiber, film, and nanotransducer-based devices, highlighting the key advantages of each platform. The possible mechanisms and main barriers for optoacoustics as a viable neuromodulation tool are discussed. Future directions in fundamental and translational research are proposed.

15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(1): 102-109, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35300771

RESUMO

Objective To explore the expression profiles of circulating microRNA(miRNA)and potential markers for the diagnosis of adult fulminant myocarditis(FM). Methods The expression profiles of circulating miRNA were determined by microarray analysis and verified by real-time quantitative PCR.The key role of circulating miRNA in FM was determined via KEGG pathway enrichment.The correlations between miRNA and cardiac function parameters in patients with FM were analyzed.The receiver operating characteristic(ROC)curve was established to evaluate the sensitivity and specificity of circulating miRNA in the diagnosis of FM. Results Compared with healthy controls,the FM patients had up-regulated expression levels of miR-29b(t=18.925,P<0.001)and miR-125b(t=5.981,P=0.029)in the plasma.After treatment,the expression levels of miR-29b(t=12.943,P<0.001)and miR-125b(t=14.016,P<0.001)were significantly down-regulated.KEGG pathway enrichment showed that the targets of miR-29b were involved in inflammatory response and apoptosis pathways.The results of cell proliferation and apoptosis assay demonstrated the transfection of miR-29b mimic had a more significant inducing effect on cardiomyocyte apoptosis than that of miR-125b mimic(χ 2=6.168,P=0.047),whereas there was no significant difference in the inhibition of cell proliferation between the two groups(χ2=1.452,P=0.417).The expression levels of miR-29b and miR-125b were negatively correlated with left ventricular ejection fraction(r=-0.67,P=0.071;r=-0.49,P=0.003).They were positively correlated with cardiac troponin I level(r=0.61,P=0.019;r=0.52,P=0.016),interferon ß level(r=0.42,P=0.014;r=0.36,P=0.021),and myocardial edema area(r=0.86,P=0.005;r=0.73,P=0.013).The ROC curve analysis demonstrated that miR-29b had higher sensitivity for the diagnosis of FM(93.6% vs.89.2%;t=0.896,P=0.795)and specificity(72.4% vs.59.6%;t=9.478,P=0.002)than miR-125b. Conclusion The circulating miR-29b may be a potential biomarker for the diagnosis of FM.


Assuntos
MicroRNA Circulante , Miocardite , Adulto , Biomarcadores/metabolismo , MicroRNA Circulante/metabolismo , Humanos , MicroRNAs/metabolismo , Miocardite/diagnóstico , Volume Sistólico , Função Ventricular Esquerda
16.
Small ; 18(17): e2200608, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35344263

RESUMO

Controlled morphology of solution-processed thin films have realized impressive achievements for non-fullerene acceptor (NFA)-based organic solar cells (OSCs). Given the large set of donor-acceptor pairs, employing various processing conditions to realize optimal morphology for high efficiency and stable OSCs is a strenuous task. Therefore, comprehensive correlations between processing conditions and morphology evolution pathways have to be developed for efficient performance and stability of devices. Within the framework of the blend system, crystallization transitions of NFA molecules are tracked utilizing the first heating scan of differential scanning calorimeter (DSC) measurement correlating with respective morphology evolution of blend films. Real-time dynamics measurements and morphology characterizations are combined to provide optimal morphology transition pathways as NFA molecules are shown to be released from the mixed-phase to form balanced ordered packing with variant processing conditions. Polymer:NFA films are fabricated using blade coating incorporating solvent additive or thermal annealing as processing conditions as a correlation is formulated between performance and stability of solar cells with morphology transition pathways. This work demonstrates the significance of processing condition-controlled transition pathways for the realization of optimal morphology leading to superior OSC devices.

17.
Front Microbiol ; 13: 830333, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35283830

RESUMO

The presence of pathogenic bacteria and antibiotic resistance genes (ARGs) in milk are among the most important issues related to the safety of dairy products and the health of consumers. However, despite that dairy cow are housed for long periods of time on different beddings, the effect of different bedding materials on the microbiota and presence of ARGs is unclear. In this study, the composition of microorganisms, and the presence of mastitis pathogens and 33 ARGs targeting seven antibiotics in raw milk produced from farms using sand bedding, rice husk bedding, and recycled manure solids (RMS) bedding were compared by amplicon sequencing and real-time quantitative PCR. The results showed that the microbial composition of milk was related to the microbiota of bedding. None of the mastitis pathogens were detected in milk from cows housed on sand bedding (S-M). The proportion of ARGs was highest in the S-M group and lowest in the milk from cows housed on RMS bedding (RMS-M) group. In general, the content of ARGs in RMS-M was the lowest, however, the RMS bedding may pose a threat to the breast health of dairy cows.

18.
Front Nutr ; 9: 831178, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237645

RESUMO

Flaxseed supplementation in diet of dairy cow can effectively enhance the production of ω-3 polyunsaturated fatty acids (n-3 PUFA) in raw milk, which further give rise to the changes of volatile organic compounds (VOCs). In this study, we used headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) to investigate the VOCs in milk from cows fed three different diets (CK: supplemented with 0 g/d flaxseed; WF: 1,500 g/d whole flaxseed and GF: 1,500 g/d ground flaxseed). A total of 40 VOCs including three acids, six esters, 11 aldehydes, seven alcohols, 13 ketones were identified in all the raw milk samples. Compared with GF supplementation, suppling with WF could influence more compounds in raw milk (GF: five compounds; WF: 22 compounds). Supplementation with WF could increase the concentration of nonanal, heptanal, hexanal, which could cause the occurrence of off-flavors, and reduce the concentration of hexanoic acid (monomer; M), 2-hexanol, ethanol (M), 2-heptanone (dimer; D), 2-pentanone (M), 2-pentanone (D), acetoin (M) in raw milk. GF supplementation in diet could reduce the 2-pentanone (M), 2-pentanone (D). In addition, principal component analysis (PCA) based on the signal intensity of identified VOCs indicated that it is possible to distinguish between the CK and WF milk. However, GF milk could not be distinguished from CK milk. The results demonstrate that compared with GF milk, WF supplementation in diet of dairy cows could increase fishy (heptanal) cardboard-like (pentanal) flavor in milk and decrease sweet (hexanoic acid, 2-heptanone), fruity (ethyl butanoate, ethyl hexanoate, 2-heptanone) flavor which may lead the milk less acceptable. In conclusion, compared with WF, GF supplementation in diet of dairy cow showed higher increase in n-3 PUFA in raw milk, and less influence in VOCs of raw milk and this study might provide theoretical supports for the production of milk rich in n-3 PUFA.

19.
Front Nutr ; 9: 822020, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252301

RESUMO

Gut microbiota dysbiosis, together with goblet cells dysfunction has been observed in ulcerative colitis cases. This study aims to evaluate the potential of 2'-fucosyllactose (2'-FL) supplementation in inhibiting intestinal inflammation through regulating gut microbiota, protecting goblet cells, and stimulating mucin secretion. 2'-FL was orally administered to C57BL/6J mice daily (400 mg/kg bw) for 21 days and 5% dextran sulfate sodium (DSS) was used to induce the colitis in the last 7 days. Meanwhile, fecal microbiota transplantation (FMT) was conducted to test the roles of gut microbiota in the remission of colitis by 2'-FL. Gut microbiota alteration was analyzed through 16S ribosomal RNA (16S rRNA) sequencing. Periodic acid-Schiff (PAS), immunofluorescence staining, as well as mucin 2 (MUC2) and NOD-like receptor family pyrin domain containing 6 (NLRP6) messenger RNA (mRNA) expression in colon fragments was performed and detected. The results showed that the DSS + 2'-FL mice were found to have a slower rate of weight loss, lower disease activity index (DAI) scores, and longer colon lengths than the DSS group (p < 0.05), so in the FMT recipient mice which received fecal microbiota from the DSS + 2'-FL group. In addition, the data revealed that 2'-FL relieved the disorder of DSS-induced gut microbiota, including decreasing the high abundance of mucin-utilizing bacteria in the DSS group, such as Bacteroides, Lachnospiraceae NK4A136, Lachnospiraceae, and Bacteroides vulgatus. PAS and immunofluorescence staining showed that 2'-FL treatment promoted the recovery of goblet cells and enhanced MUC2 and NLRP6 expression, which was also observed in the FM (DSS + 2'-FL) group. Moreover, NLRP6, which has been proved to be a negative regulator for Toll-like receptor 4/myeloid differential protein-8/nuclear factor-kappa B (TLR4/MyD88/NF-κB) pathway, was upregulated by 2'-FL in colon tissue. In conclusion, this study suggests that 2'-FL ameliorates colitis in a gut microbiota-dependent manner. The underlying protective mechanism associates with the recovery of goblet cells number and improves MUC2 secretion through TLR4-related pathway.

20.
Animals (Basel) ; 12(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35158576

RESUMO

Fatty acid profiles may affect the flavor of milk. The diversity of volatile compounds in raw milk with different ratios of n-6 to n-3 fatty acids (8:1, 4:1, and 3:1) was studied. Gas chromatography-ion mobility spectroscopy (GC-IMS) is a promising technology for the accurate characterization and detection of volatile organic compounds in agricultural products, but its application in milk is rare or even unavailable. In this experiment, GC-IMS fingerprints along with principal component analysis (PCA) were used to study the flavor fingerprints of fresh milk samples with different percentages. Thirty-four typical target compounds were identified in total. A diversity of flavor compounds in raw milk with different n-6/n-3 was observed. After reduction of the proportion, the concentrations of volatile compounds, such as hexanoic acid (dimer and monomer), ethyl acetate, and 2-methylpropanoic acid (dimer and monomer) decreased, while those of 4-methyl-2-pentanone, pentanal, and acetone increased. We carried out PCA according to the signal strength of the identified volatile compounds, and the examination showed that it could precisely make a distinction among the samples in a comparative space. In conclusion, the results show that the volatile compounds are different as the proportion is different. The volatile compounds in raw milk are mainly hexanoic acid, ethyl acetate, and 2-methylpropanoic acid. After adjustment of the ratio, the flavor substances of the medium-ratio (MR) group were mainly ketones, while those of the low-ratio (LR) group were aldehydes. Therefore, in production, reducing the impact on volatile substances while adjusting the proportion of n-6 and n-3 fatty acids to obtain functional dairy products should be taken into consideration.

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