articles+ search results

INFANT nutrition, FLUORESCENCE spectroscopy, BABY foods, MOLECULAR weights, and MILKING

Bovine α‐lactalbumin (BLA) was treated by ultrasonic at 150 W/cm2 for different times and subsequently glycated with mannose by dry‐heating. Molecular weight, intrinsic fluorescence spectra, glycation sites and degree of modified BLA were observed. The proteinaceous high molecular weight components were formed after ultrasonic prior to glycated modification, while the conformational changes were obvious. Prior to ultrasonic pretreatment, K62, K114, and K122 of BLA were identified. After treated by ultrasound at 150 W/cm2 for 5, 10, 15, and 20 min, the sites were increased to four, four, five, and five, respectively. All glycated sites of modified BLA exhibited a higher degree of substitution per peptide (DSP) values compared to native BLA. Ultrasonic at 150 W/cm2 for 20 min revealed the most significant change in the BLA structure. Therefore, conformational changes, the intensified glycation site, and DSP value were responsible for the structural changes of BLA. Practical applications: BLA is suitable as an ingredient for infant nutrition in food, and has immune‐modulating, antioxidant, antibacterial, and antitumor activity etc. This study revealed that the structural changes of BLA induced by ultrasonic prior to glycated modification. It will be beneficial to understand the mechanism of the functional changes of modified BLA. Ultrasonic prior to glycated modification will be more likely to develop a practical technology to modify protein in the food industry, and improve the functional characteristics of food, such as produce hypo‐allergenic cow's milk in future. [ABSTRACT FROM AUTHOR]

GELATIN, HYDROXYL group, FISHES, HYDROPHOBIC interactions, ELECTROSTATIC interaction, and HYDROCOLLOIDS

The effects of γ‐polyglutamic aid (γ‐PGA) on the gelling properties and non‐covalent interactions of fish gelatin were investigated. The gel strength and melting temperature of fish gelatin gradually increased, with increasing γ‐PGA concentration, although there was no significant change when the γ‐PGA concentration was greater than 0.04%. As the concentration of γ‐PGA increased, the electrostatic interaction of fish gelatin increased and the hydrophobic interaction between gelatin molecules decreased. The fish gelatin system was comprised of γ‐PGA concentrations of 0.04 and 0.06% showing a strong hydrogen bond. When the γ‐PGA concentration increased from 0 to 0.04%, more phenolic hydroxyl groups in the tyrosine residue tended to form hydrogen bonds with the protein. However, an additional increase in γ‐PGA concentration to 0.1% led to enhanced hydrogen bonding with water molecules. The results of this study showed that hydrogen bonds played an important role in improving the gelling properties of gelatin by γ‐PGA. [ABSTRACT FROM AUTHOR]

POLYSACCHARIDES, FRUIT extracts, TYPE 2 diabetes, ORGANIC acids, PREMATURE aging (Medicine), and SOLVENT extraction

This study was carried out to optimize the solvent for extracting the antioxidants and α‐glucosidase inhibitors (AGIs) from Pyracantha fortuneana fruit (PFF) and the major chemical components were characterized by HPLC‐QTOF‐MS/MS. The results showed that 50% and 70% acetone (v/v, ml/ml) gave the best extraction efficiency on phenolics and total flavonoids, while 70% acetone and 50% methanol possess better recovery on protein and polysaccharides, respectively. In addition, the 50% and 70% acetone extracts gave the strongest radical scavenging ability and α‐glucosidase inhibitory activity (p > 0.05), but the Fe3+ reducing power of the 50% acetone extract was higher than that of 70% acetone. Correlation analysis indicated that phenolic acids and flavonoids were connected to the antioxidant activity and α‐glucosidase inhibitory activity closely. Moreover, 25 compounds including 7 flavonoids, 6 phenolic acids, 7 organic acids, 3 tannins, 1 terpene, and 1 alkaloid were identified or tentatively identified in the 50% acetone extract. Overall, 50% acetone can be a proper solvent for extracting antioxidants and AGIs from PFF. Practical applications: Imbalance between production and clearance of reactive oxygen species (ROS) in the body could induce various chronic diseases. PFF is an edible fruit beneficial to human health; it is reported to be capable of optimizing blood glucose levels and may prevent premature aging. In the present study, PFF was found to be excellent in antioxidant activities and α‐glucosidase inhibitory ability; 50% acetone was found to be the best extraction solvent. In addition, the predominant phytochemical components of the 50% acetone extract were characterized. This study can promote further research of Pyracantha fortuneana in natural functional products, especially in the prevention of type II diabetes and its complication. [ABSTRACT FROM AUTHOR]

ARM innervation, PERIPHERAL nervous system physiology, PERIPHERAL nervous system, ACTION potentials (Electrophysiology), BRAIN, CEREBRAL palsy, COMPARATIVE studies, FUNCTIONAL assessment, HEMIPLEGIA, RESEARCH methodology, MEDICAL cooperation, NEUROSURGERY, RESEARCH, STATISTICAL sampling, SPASTICITY, STROKE, EVALUATION research, RANDOMIZED controlled trials, DISEASE complications, ANATOMY, and TRANSPLANTATION of organs, tissues, etc.

Background: Spastic limb paralysis due to injury to a cerebral hemisphere can cause long-term disability. We investigated the effect of grafting the contralateral C7 nerve from the nonparalyzed side to the paralyzed side in patients with spastic arm paralysis due to chronic cerebral injury.Methods: We randomly assigned 36 patients who had had unilateral arm paralysis for more than 5 years to undergo C7 nerve transfer plus rehabilitation (18 patients) or to undergo rehabilitation alone (18 patients). The primary outcome was the change from baseline to month 12 in the total score on the Fugl-Meyer upper-extremity scale (scores range from 0 to 66, with higher scores indicating better function). Results The mean increase in Fugl-Meyer score in the paralyzed arm was 17.7 in the surgery group and 2.6 in the control group (difference, 15.1; 95% confidence interval, 12.2 to 17.9; P<0.001). With regard to improvements in spasticity as measured on the Modified Ashworth Scale (an assessment of five joints, each scored from 0 to 5, with higher scores indicating more spasticity), the smallest between-group difference was in the thumb, with 6, 9, and 3 patients in the surgery group having a 2-unit improvement, a 1-unit improvement, or no change, respectively, as compared with 1, 6, and 7 patients in the control group (P=0.02). Transcranial magnetic stimulation and functional imaging showed connectivity between the ipsilateral hemisphere and the paralyzed arm. There were no significant differences from baseline to month 12 in power, tactile threshold, or two-point discrimination in the hand on the side of the donor graft.Results: The mean increase in Fugl-Meyer score in the paralyzed arm was 17.7 in the surgery group and 2.6 in the control group (difference, 15.1; 95% confidence interval, 12.2 to 17.9; P<0.001). With regard to improvements in spasticity as measured on the Modified Ashworth Scale (an assessment of five joints, each scored from 0 to 5, with higher scores indicating more spasticity), the smallest between-group difference was in the thumb, with 6, 9, and 3 patients in the surgery group having a 2-unit improvement, a 1-unit improvement, or no change, respectively, as compared with 1, 6, and 7 patients in the control group (P=0.02). Transcranial magnetic stimulation and functional imaging showed connectivity between the ipsilateral hemisphere and the paralyzed arm. There were no significant differences from baseline to month 12 in power, tactile threshold, or two-point discrimination in the hand on the side of the donor graft.Conclusions: In this single-center trial involving patients who had had unilateral arm paralysis due to chronic cerebral injury for more than 5 years, transfer of the C7 nerve from the nonparalyzed side to the side of the arm that was paralyzed was associated with a greater improvement in function and reduction of spasticity than rehabilitation alone over a period of 12 months. Physiological connectivity developed between the ipsilateral cerebral hemisphere and the paralyzed hand. (Funded by the National Natural Science Foundation of China and others; Chinese Clinical Trial Registry number, 13004466 .). [ABSTRACT FROM AUTHOR]

HOPS, STOMACH cancer, CANCER cells, ETHANES, and ALKANES

Two new prenylchalcones, xanthohumol C and D, together with two known prenylchalcone derivatives, xanthohumol (1) and 5''-(2''-hydroxyisopropyl)-dihydrofurano-[2'',3''-b]-4,4'-dihydroxy-6'-methoxy-chalcone (4) were isolated and identified from the hops of Humulus lupulus L. The structures of xanhohumol C and D were elucidated as 5''-hydroxy-6'',6''-dimethyl-dihydropyrano-[2'',3''-b]-4,4'-dihydroxy-6'-methoxy-chalcone (2) and 5''-hydroxy-6'',6''-dimethyl-dihydropyrano-[2'',3''-b]-4',6'-dimethoxy-4-hydroxy-chalcone (3) on the basis of HRFAB-MS, 1D and 2D NMR (HMQC, HMBC) spectroscopic data. Among the new prenylchalcones, compound 2 showed marginal cytotoxic activity against human stomach carcinoma BGC-823 and human hepatic carcinoma HepG2 cells. [ABSTRACT FROM AUTHOR]

NON-small-cell lung carcinoma, AUTOPHAGY (Cytology), ANTINEOPLASTIC agents, ERLOTINIB, CHINESE medicine, and CELL cycle

Magnolol and honokiol are the two major active ingredients with similar structure and anticancer activity from traditional Chinese medicine Magnolia officinalis , and honokiol is now in a phase I clinical trial (CTR20170822) for advanced non-small cell lung cancer (NSCLC). In search of potent lead compounds with better activity, our previous study has demonstrated that magnolol derivative C2 , 3-(4-aminopiperidin-1-yl)methyl magnolol, has better activity than honokiol. Here, based on the core of 3-(4-aminopiperidin-1-yl)methyl magnolol, we synthesized fifty-one magnolol derivatives. Among them, compound 30 exhibited the most potent antiproliferative activities on H460, HCC827, H1975 cell lines with the IC 50 values of 0.63–0.93 μM, which were approximately 10- and 100-fold more potent than those of C2 and magnolol, respectively. Besides, oral administration of 30 and C2 on an H460 xenograft model also demonstrated that 30 has better activity than C2. Mechanism study revealed that 30 induced G0/G1 phase cell cycle arrest, apoptosis and autophagy in cancer cells. Moreover, blocking autophagy by the autophagic inhibitor enhanced the anticancer activity of 30 in vitro and in vivo , suggesting autophagy played a cytoprotective role on 30 -induced cancer cell death. Taken together, our study implied that compound 30 combined with autophagic inhibitor could be another choice for NSCLC treatment in further investigation. New Magnolol Derivatives Synthesized for the Treatment of NSCLCHere, fifty-one magnolol derivatives were synthesized based on the core of 3-(4-aminopiperidin-1-yl)methyl magnolol, and compound 30 exhibited the most potent antiproliferative activities on H460, HCC827, H1975 cell lines with the IC 50 values of 0.63–0.93 μM. Mechanism study revealed that blocking autophagy by the autophagic inhibitor enhanced the anticancer activity of 30 in vitro and in vivo , suggesting autophagy played a cytoprotective role on 30 -induced cancer cell death. Image 1 • Series of magnolol derivatives were designed and synthesized. • Compound 30 exhibited potent antiproliferative activities in vitro and in vivo. • SAR, in vitro metabolism, and antitumor mechanism were investigated. • Blocking autophagy could enhance the anticancer activity of 30. [ABSTRACT FROM AUTHOR]

ADVANCED glycation end-products, MASS analysis (Spectrometry), VAN der Waals forces, INTERMOLECULAR interactions, FLUORESCENCE spectroscopy, and HYDROGEN bonding

Formation of advanced glycation end products (AGEs) on foods imposes threats to human health after intaking. This research firstly evaluated the inhibition of isoquercitrin on β-lactoglobulin (β-Lg) glycation, the mechanisms were elucidated by fluorescence spectroscopy, Orbitrap MSn and molecular docking. Fluorescence spectra indicated that isoquercitrin effectively alleviated the formation of AGEs, it could stabilize the conformation structure of glycated β-Lg (G-β-Lg), change the micro-environment in the vicinity of chromophores. SDS-PAGE analysis revealed the suppressed cross-linking of G-β-Lg induced by isoquercitrin. The number of glycation site detected on G-β-Lg was reduced from ten to eight after the addition of isoquercitrin, and the relative glycation degree of substitution of per site (RGDSP) of most glycation sites were also greatly decreased. As indicated by intermolecular interaction, isoquercitrin quenched the fluorescence of β-Lg via a static mechanism, and their combination is an endothermic processing mainly derived by hydrophobic interaction, hydrogen bonds, and van der Waals forces. Isoquercitrin interacted with β-Lg to form an equimolar complex, and one hydrogen bond was formed between isoquercitrin and Lys69 (4.96 Å). Above results proved that isoquercitrin can be a promising anti-glycation agent used in food system to prevent the formation of harmful glycation products. Unlabelled Image [ABSTRACT FROM AUTHOR]

ATTENUATED total reflectance, MOLECULAR structure, SURFACE active agents, FLAVOR, SCANNING electron microscopes, and COVALENT bonds

Different surfactants (lecithin, Tween‐20, and Tween‐80) were added in composite film during the preparation. Flavor, antimicrobial activity, and physical properties of ginger essential oil ‐gelatin film were investigated, in order to study the effect of surfactants on the properties of film. The flavor of GEO was not detected in the film prepared with Tween‐20 and film prepared with Tween‐80, and these two films exhibited stronger antimicrobial activity; film prepared with lecithin possessed higher value in thickness, elongation at break, water solubility, ΔE and opacity, lower value in water vapor property, and tensile strength; attenuated total reflectance‐Fourier transform infrared spectrum results suggested, Tween‐20 and Tween‐80 enhanced the strength of covalent bond, and lecithin weakened the strength of hydrogen bond; and the result of scanning electron microscope showed that Tween‐20 and Tween‐80 improved the dispersion of oil droplets in film. Therefore, this study suggested that surfactants had an influence on the physical properties and molecular structure of a resulting film; in addition, Tween‐20 and Tween‐80 could reduce the flavor of GEO in film, improving the antimicrobial activity of film. [ABSTRACT FROM AUTHOR]

PHASE modulation, RADIO frequency modulation, LUMINESCENCE, FEMTOSECOND lasers, and LASER beams

Improving the up-conversion luminescence efficiency of rare-earth ions via the multi-photon absorption process is crucial in several related application areas. In this work, we theoretically propose a feasible scheme to enhance the resonance-mediated two-photon absorption in Er3+ ions by shaping the femtosecond laser field with a rectangle phase modulation. Our theoretical results show that the resonance-mediated two-photon absorption can be decomposed into the on-resonant and near-resonant parts, and the on-resonant part mainly comes from the contribution of laser central frequency components, while the near-resonant part mainly results from the excitation of low and high laser frequency components. So, the rectangle phase modulation can induce a constructive interference between the two parts by properly designing the modulation depth and width, and finally realizes the resonance-mediated two-photon absorption enhancement. Moreover, our results also show that the enhancement efficiency of resonance-mediated two-photon absorption depends on the laser pulse width (or laser spectral bandwidth), final state transition frequency, and intermediate and final state absorption bandwidths. The enhancement efficiency modulation can be attributed to the relative weight manipulation of on-resonant and near-resonant two-photon absorption in the whole excitation process. This study presents a clear physical insight for the quantum control of resonance-mediated two-photon absorption in the rare-earth ions, and there will be an important significance for improving the up-conversion luminescence efficiency of rare-earth ions. [ABSTRACT FROM AUTHOR]

AMINO acids, PROTEOLYTIC enzymes, PEPTIDE synthesis, PHENYLALANINE, and ENZYMATIC analysis

Abstract: The peptide bond formation of N-protected non-coded amino acids having different structures as acyl donor substrates that is catalyzed by thermoase in organic media was investigated. In these reactions, N-protected l-α-non-coded amino acids, including l-Orn, l-Cit, α-aminobutyric acid (l-α-Abu) and phenylalanine homologues, were used as the acyl donors and phenylalanine derivatives were used as the acyl acceptors. This kind of enzymatic reactions cannot be carried out in an aqueous buffer due to the rigid specificity of proteases to coded amino acids in water. The results demonstrated that the substrate specificity of proteases could be broadened in organic solvents. In addition, the factors that influenced these protease-catalyzed reactions, including structures of the substrates, water content and the bases used, were systematically studied. Our work provided important evidence for broadening the application of protease in organic synthesis. [Copyright &y& Elsevier]

CHRONIC kidney failure, KIDNEY disease risk factors, DISEASE prevalence, ALBUMINURIA, ZHUANG (Chinese people), and DISEASE risk factors

Aim Numerous studies have examined and reported a high prevalence of chronic kidney disease ( CKD) in the general population in various countries including China. However, the situation may be different in undeveloped rural minority regions in China because of China's economic diversity. The aim of the present study was to estimate the prevalence of CKD and to analyze its associated factors in a Zhuang ethnic minority area in Southwest China. Methods A cross-sectional survey of a rural minority area populated by people of Zhuang ethnicity in Southwest China using multistage, cluster random sampling methods was performed. The prevalence of indicators of kidney damage and CKD were calculated and risk factors associated with the presence of CKD were analyzed. Results In total, 7588 people participated in the study. After adjustment for age and gender, the prevalence of albuminuria, haematuria and reduced estimated glomerular filtration rate were 2.7%, 3.7%, and 2.2%, respectively. After adjustment for age and gender, the prevalence of CKD was 8.3%, while recognition of the disease was 3.6%. Independent risk factors associated with CKD were age, gender, and hypertension. Risk factors independently associated with kidney damage were age, gender, hyperuricaemia, and hypertension. Conclusion Our data exhibited a lower prevalence and awareness of CKD in undeveloped rural minority regions, especially exhibited a low prevalence of albuminuria. This result attributed to the low prevalence of metabolic disorders in the local region. Risk factors associated with CKD in our study is similar to surveys in other regions of China. [ABSTRACT FROM AUTHOR]

RICE quality, AMYLOSE, GRAIN size, FLUIDIZATION, and STARCH crops

A suspension of rice amylose was subjected to dynamic high‐pressure microfluidization (DHPM) at 60, 100, 140, and 180 MPa and the effect on the microstructure and particle characteristics was investigated. After DHPM treatment, more hollows and grooves were found in the surface of the rice amylose and the particle size decreased and became uniform with an increase in pressure, which increased the specific surface area. DHPM treatment at above 100 MPa was sufficient to cause the complete destruction of the crystalline structure of rice amylose. We proposed a hypothesis of the mechanism, namely, that a decrease in particle size and puffing of granules both occurred after DHPM treatment to yield a uniform and homogeneous system. Moreover, complex DHPM forces could modify the structure and the interaction between amylose and other molecules, playing an important role in some functional properties of amylose. Practical applications: Rice is one of the most important staple food in China. Its main component is rice amylose. In this study, the structure and morphology of rice amylose treated by DHPM were analyzed. The results are helpful to understand the mechanism of the modification of amylose induced by DHPM and contribute for us to explain our previous studies of the effect of DHPM on physicochemical and functional properties of rice amylose. Meanwhile, it can also provide theoretical support for starch modification. [ABSTRACT FROM AUTHOR]

AMINO acids, SEX hormones, ESTROGEN, and STEROLS

Abstract: A series of N-protected amino acid-estradiol derivative conjugates have been synthesized by coupling of 17β-aminoestra-1,3,5 (10)-trien-3-ol ( 1 ) or 17β-hydrazonoestra-1,3,5 (10)-trien-3-ol ( 2 ) with different amino acids via the catalysis of subtilisin Carlsberg in organic solvent. Various factors, including the structure of amino acid residue, different N-protecting groups of amino acids, different esters of carboxyl group and water content of the reaction media that influence the efficiency of enzymatic reactions were systematically studied. In vitro biological activity studies revealed that the binding interactions between estradiol derivative conjugates and estrogen receptor can be affected by the properties of the conjugated amino acid, but the effects of the change in binding properties did not result in changes in biological activities in both MCF-7 and HeLa cell lines. [Copyright &y& Elsevier]

PEPTIDE synthesis, SUBTILISINS, CHYMOTRYPSIN, and ORGANIC solvents

A series of N-protected peptide alcohols were synthesized using amino alcohols with unprotected hydroxy groups as amino components by the catalysis of subtilisin or α-chymotrypsin in organic solvents. N-protected aromatic amino acid esters were more suitable as acyl donors for subtilisin. The influences of different N-protecting groups, organic solvents, and content of water on synthesis of N-protected peptide alcohols were systematically studied. [ABSTRACT FROM AUTHOR]

ORGANIC synthesis, PEPTIDES, and ALCOHOL

A series of N-protected peptide alcohols and one N-glycopeptide derivative were synthesized using DEPBT. We showed that the carboxyl group selectively reacted with amino group of the amino component in the presence of unprotected hydroxy groups. [ABSTRACT FROM AUTHOR]

GROWTH factors, PROTEOLYTIC enzymes, and PAPAIN

Full enzymatic synthesis of a fragment of osteogenic growth peptide (OGP), a precursor of bioactive pentapeptide OGP(10-14) (Z-TyrGlyPheGlyGlyOEt), was accomplished by papain, α-chymotrypsin, and thermolysin via 2+3 or 3+2 synthetic routes in organic solvents for the first time. The factors influencing the enzymatic synthesis of fragments of OGP(10-14) were systematically studied. [Copyright &y& Elsevier]