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1.
Colloids Surf B Biointerfaces ; 238: 113917, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615391

RESUMO

In this study, the encapsulation and structural characteristics of the self-assembled liposome formed by epigallocatechin gallate (EGCG) and alcohol dehydrogenase (ADH) were studied. According to the results, EGCG significantly increased the catalytic activity of ADH with a 33.33 % activation rate and the liposomes were able to entrap EGCG-ADH with an effectiveness of 88.94 %. The self-assembled monolayers had nanometer-sized particles, and the excellent self-assembled system was demonstrated by the low PDI value and high surface absolute potential. The scanning electron microscope showed that the self-assembled liposome was honeycomb, groove-shaped, and rough. The spectroscopic results showed that EGCG-ADH complex was formed through hydrogen bond, which changed the secondary structure of the liposome, and verified EGCG-ADH liposome system was successfully prepared. In vitro digestion experiments showed that the gastrointestinal tolerance and antioxidant activity of EGCG-ADH liposomes were significantly higher than those of free EGCG-ADH.

2.
Heliyon ; 10(8): e29225, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38638956

RESUMO

Preeclampsia (PE) is one of the most common complications of pregnancy and polycystic ovary syndrome (PCOS) is a prevalent metabolic and endocrinopathy disorder in women of reproductive age. Identifying the shared genetic signatures and molecular mechanisms between PCOS and PE was the objective of this study. The intersections of WGCNA module genes, PPI module genes, and PPI hub genes revealed that 8 immunity-related genes might be shared causative genes of PE and PCOS. Further, qRT-PCR results showed that TSIX/miR-223-3p/DDX58 might play a crucial role in immune dysregulation in PE and PCOS and Spearman rank correlation analysis results illustrated the potential of DDX58 as a novel diagnostic and therapeutic target for PE and PCOS. Our study demonstrated a common disease pathway model TSIX/miR-223-3p/DDX58, illustrating that immune dysregulation may be a possible mechanism of PE and PCOS, and revealed that DDX58 might be a novel predictive target for PE and PCOS.

3.
J Med Chem ; 67(7): 5259-5271, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38530741

RESUMO

A series of activators of GCN2 (general control nonderepressible 2) kinase have been developed, leading to HC-7366, which has entered the clinic as an antitumor therapy. Optimization resulted in improved permeability compared to that of the original indazole hinge binding scaffold, while maintaining potency at GCN2 and selectivity over PERK (protein kinase RNA-like endoplasmic reticulum kinase). The improved ADME properties of this series led to robust in vivo compound exposure in both rats and mice, allowing HC-7366 to be dosed in xenograft models, demonstrating that activation of the GCN2 pathway by this compound leads to tumor growth inhibition.


Assuntos
Proteínas Serina-Treonina Quinases , eIF-2 Quinase , Humanos , Camundongos , Ratos , Animais , Proteínas Serina-Treonina Quinases/metabolismo , eIF-2 Quinase/metabolismo , Camundongos Endogâmicos C57BL , RNA , Retículo Endoplasmático/metabolismo
4.
Huan Jing Ke Xue ; 45(3): 1644-1654, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471876

RESUMO

In order to explore the effects of continuous annual crop rotation and fallow on aggregate stability and organic carbon content in red soil, the red soil in sloping farmland was taken as the research object, and the water-stable aggregates and organic carbon content were determined using the wet sieve method and potassium dichromate-concentrated sulfuric acid external heating method, respectively. The changes in soil aggregate stability and organic carbon content under the four treatments of maize-vetch-maize rotation (M-V-M), maize-pea-maize rotation (M-P-M), maize-fallow-maize (M-F-M), and annual fallow (F-F-F) from 2020 to 2022 and the relationships between them were analyzed. The results showed that in 2021 and 2022, the contents of > 2 mm aggregates treated with F-F-F, M-V-M, and M-P-M were significantly increased by 67.01%-100.92%, 29.71%-33.67%, and 29.68%-38.07%, respectively, compared with that treated with M-F-M. In 2021 and 2022, the stability parameters of F-F-F and M-V-M were significantly higher than those of M-F-M (P < 0.05). The content of > 2 mm aggregates, geometric mean diameter (GMD), and mean weight diameter (MWD) under the M-V-M treatment and R0.25 (> 0.25 mm aggregate contents), MWD and > 2 mm aggregate contents under the F-F-F treatment increased with the increase in fallow years, whereas the content of 1-2 mm and < 0.25 mm under the F-F-F treatment decreased with the increase in fallow years. Both green manure rotation and fallow treatment could increase the SOC content, and the SOC content of F-F-F and M-V-M treatment increased with the extension in age. Correlation analysis showed that SOC content was significantly positively correlated with R0.25 and GMD under all treatments. R0.25 and GMD under the F-F-F treatment and GMD and MWD under M-V-M were significantly positively correlated with SOC content. The results showed that continuous annual crop rotation and fallow was beneficial to improve the content of soil macro-aggregates, aggregate stability, and SOC content, which could provide theoretical basis for the implementation of reasonable continuous annual crop rotation and fallow patterns and soil erosion control in red soil areas of sloping farmland in southern China.

5.
Angew Chem Int Ed Engl ; 63(16): e202401214, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38393606

RESUMO

It is essential to probe the coordination number (CN) because it is a crucial factor to ensure the catalytic capability of single-atom catalysts (SACs). Currently, synchrotron X-ray absorption spectroscopy (XAS) is widely used to measure the CN. However, the scarcity of synchrotron X-ray source and complicated data analysis restrict its wide applications in determining the CN of SACs. In this contribution, we have developed a d-band center-regulated acetone cataluminescence (CTL) probe for a rapid screening of the CN of Pt-SACs. It is disclosed that the CN-triggered CTL is attributed to the fact that the increased CN could induce the downward shift of d-band center position, which assists the acetone adsorption and promotes the subsequent catalytic reaction. In addition, the universality of the proposed acetone-CTL probe is verified by determining the CN of Fe-SACs. This work has opened a new avenue for exploring an alternative to synchrotron XAS for the determination of CN of SACs and even conventional metal catalysts through d-band center-regulated CTL.

6.
BMC Pregnancy Childbirth ; 24(1): 160, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395789

RESUMO

BACKGROUND: Elevated maternal serum uric acid (UA) levels were associated with adverse perinatal outcomes. This study aimed to examine the association between UA and the risk of low birth weight (LBW) / small for gestational age (SGA). METHODS: A cohort study of women delivered in Shanghai maternity hospital was included between 2017 and 2021. Electronic medical records were utilized to extract information and antenatal care records. The cut-off value of UA was 360 µmol/L. The outcome was LBW/SGA, with LBW defined as birth weight below 2500 g and SGA indicating birth weight below the 10th percentile of average weight for gestational age. The assessment of SGA was based on the Chinese standard curve for birth weight at various gestational ages. Univariate, multivariate logistic regression models, restricted cubic spline were used in this study, with adjustments made for confounding factors. RESULTS: Sixty-nine thousand six hundred seventy-four live births and singleton pregnancies were included. The ratio of LBW/SGA was 3.3%/9%. Maternal UA levels were significantly negatively correlated with birth weight. High UA levels were associated with high risk of LBW/SGA, especially in third trimester. In BMI < 25 group, the risk of LBW increased to 2.35-fold (95%CI, 1.66-3.31) in hyperuricemic group (UA > 360 µmol/L). The SGA risk was 1.66-fold (95%CI, 1.37-2.00). Gestational hypertension (GH) with hyperuricemica increased the risk of LBW (aOR = 4.00, 95%CI, 2.01-7.93) and SGA (aOR = 2.63, 95%CI, 1.83-3.78). Preeclampsia (PE) with hyperuricemia increased the risk of LBW (aOR = 1.38, 95%CI, 0.63-3.03) and SGA (aOR = 1.81, 95%CI, 1.18-2.78). In delivery gestational week (DGW) ≥ 37 group, if UA > 360 µmol/L, the incidence of LBW increased to 2.46-fold (95%CI, 1.62, 3.73) and the incidence of SGA increased to 1.52-fold (95%CI, 1.24, 1.87). In DGW < 37 group, if UA > 360 µmol/L, the incidence of LBW increased to 2.70-fold (95%CI, 1.92, 3.80) and the incidence of SGA increased to 2.13-fold(95%CI, 1.50, 3.02). CONCLUSIONS: The study found an inverse correlation between UA levels and birth weight. High UA levels were associated with increased risk of LBW/SGA, particularly in third trimester. GH or PE complicated by hyperuricemia were found to have significantly higher risk of developing LBW/SGA. This relationship also existed in pregnant women with BMI < 25.


Assuntos
Hipertensão Induzida pela Gravidez , Hiperuricemia , Nascimento Prematuro , Recém-Nascido , Feminino , Gravidez , Humanos , Ácido Úrico , Peso ao Nascer , Recém-Nascido Pequeno para a Idade Gestacional , Estudos de Coortes , Estudos Retrospectivos , Hiperuricemia/epidemiologia , China/epidemiologia , Recém-Nascido de Baixo Peso , Nascimento Prematuro/epidemiologia
7.
Clin Nucl Med ; 49(5): 468-469, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377388

RESUMO

ABSTRACT: 18 F-FDG PET/CT was performed in a 1-year-old girl who had a heterogeneous mass in the right abdominal cavity revealed by abdominal ultrasound. A heterogeneous mass with internal necrosis, cystic changes, and hemorrhage in the right kidney, accompanied by a slight increase of FDG uptake, was observed in FDG PET/CT. Malignant renal tumor was considered, and Wilms tumor was preferentially suspected. However, the mass was demonstrated as clear cell sarcoma of the kidney by histopathological examination.


Assuntos
Neoplasias Renais , Sarcoma de Células Claras , Feminino , Humanos , Lactente , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Sarcoma de Células Claras/diagnóstico por imagem , Rim/patologia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia
8.
Mol Brain ; 17(1): 8, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350944

RESUMO

Inositol pyrophosphates are key signaling molecules that regulate diverse neurobiological processes. We previously reported that the inositol pyrophosphate 5-InsP7, generated by inositol hexakisphosphate kinase 1 (IP6K1), governs the degradation of Na+/K+-ATPase (NKA) via an autoinhibitory domain of PI3K p85α. NKA is required for maintaining electrochemical gradients for proper neuronal firing. Here we characterized the electrophysiology of IP6K1 knockout (KO) neurons to further expand upon the functions of IP6K1-regulated control of NKA stability. We found that IP6K1 KO neurons have a lower frequency of action potentials and a specific deepening of the afterhyperpolarization phase. Our results demonstrate that deleting IP6K1 suppresses neuronal excitability, which is consistent with hyperpolarization due to an enrichment of NKA. Given that impaired NKA function contributes to the pathophysiology of various neurological diseases, including hyperexcitability in epilepsy, our findings may have therapeutic implications.


Assuntos
Inositol , ATPase Trocadora de Sódio-Potássio , Transdução de Sinais , Transporte Proteico , Neurônios/fisiologia
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123943, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38277788

RESUMO

Alcohol dehydrogenase (ADH) is one of the pivotal enzymes for alcohol metabolism, which plays an important role in many physiological processes. In this study, the activation effects of epigallocatechin-3-O-gallate (EGCG) on ADH and the characteristics of the interaction were investigated via biochemical method, spectroscopy methods, and molecular docking. The results demonstrated that EGCG significantly increased the catalytic activity of ADH with a 33.33% activation rate and that EGCG blending slightly altered the microenvironment surrounding ADH aromatic amino acids, with an increase in the quantity of ß-sheet and a decrease in the α-helix. Through the thermal stability analysis, it is further shown that the interaction of the two affects the intra-molecular hydrogen bond formation of the protein, and the conformation is partially extended. Besides, a total of 8 residues in ADH participated in the docking with EGCG, among which Asp-227, Lys-231, Glu-234, Gly-365 and Glu-366 participated in the formation of hydrogen bonds. At the same time, EGCG and amino group of Lys-231 form a noncovalent bond through cation-π interaction. In particular, hydrogen bonding was beneficial to keep the stability of EGCG-ADH, which was the primary driver of ADH activity activation. The results supply a new way for EGCG to activate ADH and a theoretical basis for the development of anti-alcoholism products.


Assuntos
Álcool Desidrogenase , Catequina , Catequina/análogos & derivados , Simulação de Acoplamento Molecular , Álcool Desidrogenase/metabolismo , Conformação Molecular , Análise Espectral , Catequina/farmacologia
10.
J Cell Biochem ; 125(3): e30526, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38229533

RESUMO

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are devastating neurodegenerative diseases with no effective cure. GGGGCC repeat expansion in C9orf72 is the most common genetic cause of both ALS and FTD. A key pathological feature of C9orf72 related ALS/FTD is the presence of abnormal dipeptide repeat proteins translated from GGGGCC repeat expansion, including poly Glycine-Arginine (GR). In this study, we observed that (GR)50 conferred significant mitochondria damage and cytotoxicity. Metformin, the most widely used clinical drug, successfully relieved (GR)50 induced mitochondrial damage and inhibited (GR)50 related cytotoxicity. Further research revealed metformin effectively restored mitochondrial function by upregulating AKT phosphorylation in (GR)50 expressed cells. Taken together, our results indicated restoring mitochondrial function with metformin may be a rational therapeutic strategy to reduce poly(GR) toxicity in C9orf72 ALS/FTD patients.


Assuntos
Esclerose Amiotrófica Lateral , Demência Frontotemporal , Humanos , Demência Frontotemporal/tratamento farmacológico , Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Esclerose Amiotrófica Lateral/tratamento farmacológico , Esclerose Amiotrófica Lateral/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Fosforilação , Dipeptídeos
11.
Clin Imaging ; 106: 110032, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042047

RESUMO

INTRODUCTION: This retrospective study aimed to evaluate clinical outcomes of monochorionic diamniotic (MCDA) twins with selective intrauterine growth restriction (sIUGR). MATERIALS AND METHODS: MCDA twins, either sIUGR and non-sIUGR, underwent expectant management from 2016 to 2019 in our hospital were included. sIUGR fetuses were classified into three types according to umbilical artery Doppler assessment. Non-sIUGR were considered as the control group. Outcomes were pregnancy outcomes and maternal complications. RESULTS: Forty-three sIUGR (type I: 23; type II: 14, and type III: 6) and 282 non-sIUGR fetuses were included. The sIUGR group had a significantly earlier birth, lower birth weight of the twins, larger inter-twin weight difference, lower Apgar score of the twins, and higher intrauterine fetal death (IUFD) than the non-sIUGR group (all p < 0.001). The same trend was found in the sIUGR type II group compared to type I and III groups. A significantly lower gestational diabetes rate (p = 0.01) and placenta weight (p < 0.001), and higher proportions of abnormal placental umbilical cord insertion (p < 0.001), and ultrasound Doppler monitoring indicators (p = 0.006) were found in the sIUGR group than the non-sIUGR group. CONCLUSIONS: The MCDA twins with sIUGR showed poorer outcomes than the non-sIUGR group. Doppler interrogation was a useful clinical marker for fetal outcome.


Assuntos
Retardo do Crescimento Fetal , Gravidez de Gêmeos , Gravidez , Feminino , Humanos , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/epidemiologia , Placenta , Estudos Retrospectivos , Gêmeos Monozigóticos , Ultrassonografia Pré-Natal
12.
J Cardiovasc Transl Res ; 17(1): 197-215, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37615888

RESUMO

Water-soluble myo-inositol phosphates have long been characterized as second messengers. The signaling properties of these compounds are determined by the number and arrangement of phosphate groups on the myo-inositol backbone. Recently, higher inositol phosphates with pyrophosphate groups were recognized as signaling molecules. 5-Diphosphoinositol 1,2,3,4,6-pentakisphosphate (5PP-InsP5) is the most abundant isoform, constituting more than 90% of intracellular inositol pyrophosphates. 5PP-InsP5 can be further phosphorylated to 1,5-bisdiphosphoinositol 2,3,4,6-tetrakisphosphate (InsP8). These two molecules, 5PP-InsP5 and InsP8, are present in various subcellular compartments, where they participate in regulating diverse cellular processes such as cell death, energy homeostasis, and cytoskeletal dynamics. The synthesis and metabolism of inositol pyrophosphates are subjected to tight regulation, allowing for their highly specific functions. Blocking the 5PP-InsP5/InsP8 signaling pathway by inhibiting the biosynthesis of 5PP-InsP5 demonstrates therapeutic benefits in preclinical studies, and thus holds promise as a therapeutic approach for certain diseases treatment, such as metabolic disorders.


Assuntos
Difosfatos , Fosfatos de Inositol , Animais , Fosfatos de Inositol/metabolismo , Transdução de Sinais , Mamíferos/metabolismo
13.
Clin Hypertens ; 29(1): 32, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38037134

RESUMO

BACKGROUND: In all studies conducted so far, there was no report about the correlation between excessive gestational weight gain (GWG) and the risk of preeclampsia (PE) in multiparas, especially considering that multiparity is a protective factor for both excessive GWG and PE. Thus, the aim of this retrospective cohort study was to determine whether GWG of multiparas is associated with the increased risk of PE. METHODS: This was a study with 15,541 multiparous women who delivered in a maternity hospital in Shanghai from 2017 to 2021, stratified by early-pregnancy body mass index (BMI) category. Early-pregnancy body weight, height, week-specific and total gestational weight gain as well as records of antenatal care were extracted using electronic medical records, and antenatal weight gain measurements were standardized into gestational age-specific z scores. RESULTS: Among these 15,541 multiparous women, 534 (3.44%) developed preeclampsia. The odds of preeclampsia increased by 26% with every 1 z score increase in pregnancy weight gain among normal weight women and by 41% among overweight or obese women. For normal weight women, pregnant women with preeclampsia gained more weight than pregnant women without preeclampsia beginning at 25 weeks of gestation, while accelerated weight gain was more obvious in overweight or obese women after 25 weeks of gestation. CONCLUSIONS: In conclusion, excessive GWG in normal weight and overweight or obese multiparas was strongly associated with the increased risk of preeclampsia. In parallel, the appropriate management and control of weight gain, especially in the second and third trimesters, may lower the risk of developing preeclampsia.

14.
Am J Perinatol ; 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38154467

RESUMO

OBJECTIVE: This study investigated the clinical outcome of monochorionic diamniotic (MCDA) twins with selective intrauterine growth restriction (sIUGR). STUDY DESIGN: International Peace Maternal and Child Health Hospital of Shanghai ultrasound database was investigated to identify all MCDA delivered from January 2013 to December 2017. After identifying 43 pairs of MCDA twins with sIUGR and 282 pairs of normal MCDA twins, we compared clinical outcomes between the two groups. RESULTS: Compared with normal twins, sIUGR fetuses had significantly shorter gestational age at delivery, smaller average birth weight of both twins, more significant intertwin difference in birth weight, lower Apgar scores, and higher intrauterine fetal demise (IUFD) rate, and smaller placental weight. The rate of abnormal umbilical cord insertions and abnormal blood flow in the ductus venosus (DV) and middle cerebral artery (MCA) is significantly higher in the sIUGR group. In addition, the subtype analysis of sIUGR groups indicated the poorest outcomes in type II with no significant difference between type I and III. CONCLUSION: MCDA twins with sIUGR generally exhibited limited clinical outcomes than normal MCDA twins. These limitations are mainly associated with abnormal umbilical cord insertions and blood flow in the DV and MCA. Clinical outcomes differed among the three types of sIUGR, with type II having the worst prognosis and the highest IUFD rate. KEY POINTS: · sIUGR generally exhibited limited clinical outcomes than normal MCDA twins.. · These limitations are mainly associated with blood flow of the DV and MCA.. · sIUGR with type II has the worst prognosis and the highest IUFD rate..

15.
BMC Pediatr ; 23(1): 577, 2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980516

RESUMO

OBJECTIVE: This study aimed to investigate the genetic etiologies of fetuses with single atria and/or ventricle (SA or/and SV) using different genetic detection methods in a Chinese prenatal cohort. METHODS: In this retrospective study, the various genetic results of 44 fetuses with SA and/or SV were analyzed. All 44 cases were tested by chromosomal microarray analysis (CMA) and karyotyping simultaneously, and 8 underwent whole exome sequencing (WES). Data on the pregnancy outcomes and neonatal prognoses were collected from medical records and postnatal follow-up. RESULTS: The whole cohort of 44 fetuses included 14 SA cases (31.8%), 12 SV cases (27.3%), and 18 SA and SV cases (40.9%). A total of 9 pathogenic genetic results were detected by conventional karyotyping, CMA and trio-WES, indicating an overall detection rate of 20.5% (9/44). Six pathogenic chromosomal abnormalities were identified by CMA among the 44 cases, showing a detection rate of 13.6% (6/44). Two microdeletions being missed by karyotyping were diagnosed by CMA, showing an additional diagnostic yield of 4.5% for CMA in present cohort(2/44). Three pathogenic variants in two fetuses were identified by WES, indicating an incremental diagnostic yield of 4.5%(2/44) for WES in fetuses with SA or/and SV. CONCLUSION: In this study, WES achieved an additional diagnostic yield of 4.5% in fetuses with SA or/and SV. WES is valuable for fetal prognosis assessment and could add diagnostic value for fetuses with SA and/or SV when CMA is negative. It would be a valuable technique for the identification of underlying pathogenic variants in prenatal cohorts.


Assuntos
Cardiopatias Congênitas , Diagnóstico Pré-Natal , Gravidez , Feminino , Recém-Nascido , Humanos , Diagnóstico Pré-Natal/métodos , Estudos Retrospectivos , População do Leste Asiático , Testes Genéticos/métodos , Aberrações Cromossômicas , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/genética , Feto
16.
Soft Matter ; 19(38): 7443-7458, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37747041

RESUMO

By considering the hydrolysates of soy protein produced by trypsin as an example, the emulsion stabilizing properties of plant-based protein fragments have been investigated theoretically. We apply Self-Consistent-Field (SCF) calculations to determine the colloidal interactions induced between a pair of droplets stabilized by adsorbed layers of various soy protein fragments. The study is extended to conjugates of such polypeptides, formed by covalent bonding with a suitable hydrophilic sidechain (e.g. a polysaccharide). Our results show that the relatively longer fragments, with a greater number of hydrophobic amino acids, will display a stronger degree of adsorption affinity compared to the smaller hydrolysates, even where the latter may have a higher overall ratio of hydrophobic residues. This suggested that the degree of protein hydrolysis should be carefully controlled and limited to modest values to avoid the generation of a large number of short polypeptides, while still sufficient to improve solubility. While the emulsion stabilizing performance of a protein fragment type is strongly dependent on the conformation it adopts on the interface, we find this to be less critical for the conjugated polypeptides. However, we argue that with increasing degree of hydrolysis, many small fragments will not have the chance to form bonds with polysaccharides. It is demonstrated that the abundance of these unreacted polypeptides in the system severely reduces the efficiency of the conjugated longer protein fragments, preventing their presence on the surface of the droplets through competitive adsorption process.


Assuntos
Peptídeos , Proteínas de Soja , Emulsões/química , Proteínas de Soja/química , Hidrólise , Peptídeos/química , Polissacarídeos/química , Proteínas de Plantas
18.
Food Chem ; 429: 136856, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37459711

RESUMO

The effects of frozen storage (-18 °C, 180 days) on the quality of frozen whole buckwheat extruded noodles (FWBEN) were investigated. The water content of FWBEN decreased, while the reheating time, water absorption, and dry consumption rate increased with prolonged storage time. Cooking loss increased from 3.20% to 4.31%. Texture analysis indicated that the hardness initially increased, then decreased. Microstructure results showed that the starch gel structure was damaged to a certain extent after storage for a longer period of time, whereas the porous structure became non-uniform with the appearance of cracks. The relative crystallinity gradually increased, and the freezable water content decreased with prolonged storage. These results demonstrated that FWBEN quality was affected by starch retrogradation and ice recrystallization. In general, FWBEN quality was relatively stable during 180 days of frozen storage at -18 °C.


Assuntos
Fagopyrum , Armazenamento de Alimentos , Fagopyrum/química , Amido/química , Temperatura Baixa , Água/química , Farinha
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 301: 122966, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37327498

RESUMO

With the increasing demand for functional foods, the study on binding of active molecules and ovalbumin (OVA) via weak interaction has attracted widespread attention. In this work, the interaction mechanism of OVA and caffeic acid (CA) was revealed using fluorescence spectroscopy and dynamics simulation. The CA-induced fluorescence decrease of OVA was static quenching. Their binding complex had about 1 binding site and a 3.39 × 105 L·mol-1 affinity ability. Based on thermodynamic calculations and molecular dynamics simulation, the complex structure of OVA and CA were stable using hydrophobic interactions as the main force, where CA preferred to interact with a stable binding pocket consisting of E256, E25, and V200 with N24 amino acid residues. In the binding process of CA and OVA, the conformation of OVA was altered with a slight reduction of α-helix and ß-sheet. The reduced molecular volume and more compact structure of the protein indicated that CA is beneficial to the structural stability of OVA. The research provides some new insights into the interaction between dietary proteins and polyphenols, expanding the application prospects of OVA as a carrier.


Assuntos
Simulação de Dinâmica Molecular , Ovalbumina/química , Espectrometria de Fluorescência/métodos , Sítios de Ligação , Simulação de Acoplamento Molecular , Ligação Proteica
20.
Sensors (Basel) ; 23(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37300081

RESUMO

The onboard atomic frequency standard (AFS) is a crucial element of Global Navigation Satellite System (GNSS) satellites. However, it is widely accepted that periodic variations can influence the onboard AFS. The presence of non-stationary random processes in AFS signals can lead to inaccurate separation of the periodic and stochastic components of satellite AFS clock data when using least squares and Fourier transform methods. In this paper, we characterize the periodic variations of AFS using Allan and Hadamard variances and demonstrate that the Allan and Hadamard variances of the periodics are independent of the variances of the stochastic component. The proposed model is tested against simulated and real clock data, revealing that our approach provides more precise characterization of periodic variations compared to the least squares method. Additionally, we observe that overfitting periodic variations can improve the precision of GPS clock bias prediction, as indicated by a comparison of fitting and prediction errors of satellite clock bias.

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