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1.
Provitamin A (proVA) carotenoids are converted into retinol (vitamin A) in the human body, are the subject of human nutrition studies, and are targets for biofortification of staple crops. β-Carotene has been the principal target for enhancing levels of proVA. There is recent interest in enhancing the proVA carotenoid β-cryptoxanthin since it has excellent bioavailability, and in maize may be nearly as effective as β-carotene in providing retinol to humans. This study was designed to enhance our understanding of the genetic control of: levels of β-cryptoxanthin, conversion of β-carotene into β-cryptoxanthin and zeaxanthin, conversion of β-cryptoxanthin into zeaxanthin, and flux into and within the β-branch of carotenoid pathway. A biparental population derived from two inbreds with relatively high levels of β-cryptoxanthin and different ratios of β-carotene to β-cryptoxanthin and β-cryptoxanthin to zeaxanthin was studied. Three field replications of this F2:3 population were grown, grain analyzed by liquid chromatography (LC), and composite interval mapping (CIM) performed to identify 90 quantitative trait loci (QTL) for carotenoids. We detected QTL for β-carotene/(β-cryptoxanthin + zeaxanthin) and (β-carotene + β-cryptoxanthin)/zeaxanthin ratios that contain candidate gene hydroxylase 4 (hyd4), which has not been previously associated with QTL for carotenoids in maize grain. Two color assessment methods, visual score and chromameter reading, were used to phenotype one replicate of the population for initial assessment as simple alternative measuring procedures. A common finding for LC and chromameter analysis included QTL on chromosome 5 that contain candidate gene lycopene β cyclase (lcyβ).  相似文献   

2.
Context: Poly-l-glutamic acid (PGA) is an anionic polymer with a large number of carboxyl groups that can interact electrostatically with cationic drugs such as doxorubicin (DOX).

Objective: For stable encapsulation of DOX into liposomes, we prepared triethylamine (TEA)-PGA-liposomes using PGA as an internal trapping agent.

Methods: We prepared TEA-PGA-liposomes by remote loading of DOX with a TEA gradient into preformed liposomes prepared with 1, 2, or 4?mg/mL PGA (molecular weights 4800, 9800, and 20 500), and evaluated their biodistribution and antitumor effects on Lewis lung carcinoma (LLC) tumor-bearing mice.

Results: TEA-PGA-liposomes using the higher the molecular weight or concentration of PGA showed a slower release of DOX from the liposomes. TEA-PGA-liposomes prepared with a high concentration of PGA could enhance DOX accumulation in tumors and prolonged DOX circulation in the serum, indicating that DOX may be retained stably in the liposomal interior by interaction with PGA. Furthermore, injection of TEA-PGA-liposomes prepared with 4?mg/mL of PGA9800 or 2?mg/mL PGA20500 strongly inhibited tumor growth in LLC tumor-bearing mice.

Conclusions: PGA may be a potential trapping agent for liposomal DOX for tumor drug delivery.  相似文献   


3.
Organochalcogen (S/Se) functionalized chrysin derivatives were synthesized and coordinated with RuII(η6-p-cymene) to efficiently form ruthenium-based chemotherapeutic drug entities [C31H35O4SRuCl]; [C31H35O4SeRuCl]; [C33H31O4SRuCl]; and [C33H31O4SeRuCl]. The complexes were thoroughly characterized by analytical and various spectroscopic techniques which include elemental analysis, UV–vis, IR, NMR (1H, 13C, and 77Se NMR), and HR-MS. The interaction studies of these Ru(II) complexes were carried out with CT DNA/HSA by employing UV–vis, fluorescence and circular dichroic techniques in view to examine their chemotherapeutic potential. The complexes demonstrated predominant binding toward CTDNA via electrostatic interaction while, the extent of binding was quantified by calculating intrinsic binding constant (Kb) and binding constant (K) values which revealed higher binding affinity of selenium-based chrysin complexes as compared to their thio-analogs, following the order [C31H35O4SeRuCl]?>?[C33H31O4SeRuCl]?>?[C31H35O4SRuCl]?>?[C33H31O4SRuCl]. Moreover, interaction of these complexes with human serum albumin (HSA) was also investigated which suggested spontaneous interactions of complexes with the protein by hydrogen bonding and van der Waals forces. To visualize the preferential binding sites and affinity of complexes with DNA and HSA molecular docking studies were performed. Additionally, in vitro anticancer activity of the complexes were evaluated by SRB assay on selected cancer cell lines viz., HeLa (cervical), MIA-PA-CA-2 (pancreatic), MCF-7 (breast), Hep-G2 (Hepatoma), and SK-OV-3 (ovarian) which exhibited the superior cytotoxicity of complex [C31H35O4SeRuCl] as compared to other analogs on selective cancer phenotypes.

Communicated by Ramaswamy H. Sarma  相似文献   


4.
In this study, a new lanthanum (III)-amino acid complex utilizing cysteine has been synthesized and characterized. The anticancer activities of the prepared La(III) complex against MCF-7 cell lines were studied. Results of MTT assay showed that at all three incubation times, the cytotoxic effect of prepared La(III) complex on MCF-7 breast cancer cell lines displays a time- and dose-dependent inhibitory effects. The interactions of the La(III) complex with two whey proteins (bovine serum albumin, BSA, and Bovine β-lactoglobulin, βLG) have been explored by using spectroscopic and molecular dicking methods. The obtained results indicated that La(III) complex strongly quenched the fluorescence of two carrier proteins in static quenching mode and also, BSA hah stronger binding affinity toward studied complex than βLG whit binding constant values of KBSA-La?Complex?~?0.11?×?104 M?1 and KβLG-La?Complex?~?0.63?×?103 M?1 at 300 K. The thermodynamic parameters revealed the contribution of hydrogen bond and Vander Waals interactions in both systems. The distances of the La(III) complex whit whey proteins were calculated using Förster energy transfer theory and proved existence of the energy transfer between two proteins and prepared La(III) complex with a high probability. FT-IR and UV–Vis absorption measurements indicated that the binding of the La(III) to BSA and βLG may induce conformational and micro-environmental changes of the proteins. The docking results indicate that the La(III) complex bind to residues located in the site II of BSA and second site of βLG.

Communicated by Ramaswamy H. Sarma  相似文献   


5.
Objectives: In this study, an improved lyophilized PEGylated liposomal formulation of docetaxel (DOC) has been developed.

Methods: PEGylated docetaxel liposome (PL-DOC) was prepared by thin-film evaporation method and lyophilization. The effect of various components of the lipids and their compatibility with DOC on the entrapment efficiency (EE) of liposome was investigated. The lyophilized PL-DOC was characterized by morphology, particle size, zeta potential, EE, release in vitro and stability. Pharmacokinetics and biodistribution in vivo of lyophilized PL-DOC were also investigated.

Results: The optimal liposome formulation was egg phosphatidylcholine (EPC):cholesterol (CH):DSPE-PEG2000:DOC?=?56:40:4:4 (molar ratio). Sucrose and mannitol were chosen as cryoprotectant in the lyophilization (cryoprotectant-to-lipid (C/L) mass ratio = 8:1). The size of lyophilized PL-DOC was 152.3?±?1.0?nm with negative charge and the EE was 89.75?±?1.79%. Compared with nonlyophilized PL-DOC, the lyophilized PL-DOC was more stable at 4?°C for six months. The lyophilized PL-DOC also showed the good stability after reconstituted by 5% glucose injection. In vitro release study of PL-DOC showed that PL-DOC had a sustained release effect. After i.v. administration at the dose of 10?mg/kg in rats, a significant increase in the AUC0-∞, MRT0-∞ and t1/2 was observed in PL-DOC group compared with conventional docetaxel liposome (CL-DOC) and DOC injection (DOC-I) group. Biodistribution studies in mice showed that PL-DOC significantly decreased the uptake by the organs of mononuclear phagocytic system (MPS), such as liver and spleen, while prolonging the retention time of DOC in the plasma.

Conclusion: Our PEGylated liposome formulation reported in this study could potentially produce viable clinical strategies for improved delivery of DOC for the treatment of human cancer.  相似文献   


6.
The interaction studies of CuII nalidixic acid–DACH chemotherapeutic drug entity, [C36H50N8O6Cu] with serum albumin proteins, viz., human serum albumin (HSA) and bovine serum albumin (BSA) employing UV–vis, fluorescence, CD, FTIR and molecular docking techniques have been carried out. Complex [C36H50N8O6Cu] demonstrated strong binding affinity towards serum albumin proteins via hydrophobic contacts with binding constants, K?=?3.18?×?105 and 7.44?×?104 M–1 for HSA and BSA, respectively implicating a higher binding affinity for HSA. The thermodynamic parameters ΔG, ΔH and ΔS at different temperatures were also calculated and the interaction of complex [C36H50N8O6Cu] with HSA and BSA was found to be enthalpy and entropy favoured, nevertheless, complex [C36H50N8O6Cu] demonstrated higher binding affinity towards HSA than BSA evidenced from its higher binding constant values. Time resolved fluorescence spectroscopy (TRFS) was carried out to validate the static quenching mechanism of HSA/BSA fluorescence. The collaborative results of spectroscopic studies indicated that the microenvironment and the conformation of HSA and BSA (α–helix) were significantly perturbed upon interaction with complex [C36H50N8O6Cu]. Hirshfeld surfaces analysis and fingerprint plots revealed various intermolecular interactions viz., N–H····O, O–H····O and C–H····O linkages in a 2–dimensional framework that provide crucial information about the supramolecular architectures in the complex. Molecular docking studies were carried out to ascertain the preferential binding mode and affinity of complex [C36H50N8O6Cu] at the target site of HSA and BSA. Furthermore, only for Transmission electroscopy microscopy micrographs of HSA and BSA in presence of complex [C36H50N8O6Cu] revealed major protein morphological transitions and aggregation which validates efficient delivery of complex by serum proteins to the target site.

Communicated by Ramaswamy H. Sarma  相似文献   


7.
The author investigated the presence of various carotenoids in the different parts of the body of Pungitius pungitius (L.) and Gasterosteus aculeatus L. by means of columnar and thin-layer chromatography. The investigations revealed the presence of the following carotenoids:
  • in Pungitius pungitius. α-carotene, β-carotene, β-cryptoxanthin, mutatochrome, zeaxanthin and astaxanthin;
  • in Gasterosteus aculeatus: β-carotene, β-cryptoxanthin, β-carotene epoxide, neothxanthin, canthaxanthin, mutatochrome, lutein, phoenicoxanthin, zeaxanthin, taraxanthin, tunaxanthin, astaxanthin, astaxanthin ester and α-doradexanthin. The total carotenoid content ranged from 2.229 to 138.504 µg/g wet weight.
  •   相似文献   

    8.
    Objective: To investigate the dynamic variation in H3K4me3 and HP1 with employment length in nickel smelting workers.

    Methods: Blood samples were collected from 140 nickel smelting workers and 140 age-matched office workers to test for H3K4me3, and HP1 levels.

    Results: H3K4me3 was statistically significantly different (p?<?0.05) between the two groups and positively correlated with employment length (rs?=?0.267). HP1 was not correlated with employment length (p?=?0.066) but was significantly different between the two groups.

    Conclusions: Chronic exposure to nickel can induce oxidative damage, and increase H3K4me3 expression and inhibit HP1 expression.  相似文献   


    9.
    Synthesis of a β-OHTyr-containing Bk analogue, a cyclic octalipopeptide with antifungal activities, is described. Since β-OHTyr-containing peptides generally are unstable in strong acidic conditions, synthesis of β-HOTyr-containing peptides by SPPS have rarely been reported. To overcome this problem, we found that using distilled TFA removed the protecting groups of side chains of β-OHTyr-containing Bk analogue, which was prepared by Fmoc-SPPS.

    Abbreviations: β-OHTyr: β-hydroxytyrosine; β-OHAsn: β-hydroxyasparagine; Bk: burkholdine; FAA: fatty acyl amino acid; β-MeOTyr: β-methoxytyrosine; SPPS: solid phase peptide synthesis; MIC: minimun inhibitory concentration; DMF: dimethyl formamide; DIPEA: diisopropylethylamine; DIPC: diisopropylcarbodiimide; HOBt: 1-hydroxybenzotriazole; Fmoc: 9-fluorenylmethyloxycarbonyl; HFIP: 1,1,1,3,3,3-hexafluoropropan-2-ol; TFA: trifluoroacetic acid; LAP: N-lauryl ?3-amino-4-carbamolypropanoic acid; HPLC: high performance liquid chromatography; ESI-TOFMS: electrospray ionization-time of flight mass spectrometry; Bn: benzyl; Boc: t-butyloxycatbonyl; 2-CTC: 2-chlorotritylchloride.  相似文献   


    10.
    Of the six carotenoids identified in the cyanobacterium Aphanocapsa, β-carotene, zeaxanthin, echinenone and myxoxanthophyll are the major pigments, whilst β-cryptoxanthin and 3-hydroxy-4-keto-β-carotene are present only in trace amounts. With the exception of zeaxanthin, the other xanthophylls could be formed in vitro from [14C]phytoene in high yields, especially β-cryptoxanthin and 3-hydroxy-4-keto-β-carotene. In a time course experiment of xanthopyll biosynthesis the flow of radioactivity from [14C]phytoene was followed through the pools of phytofluene, lycopene, and β-carotene. The reaction sequence from phytoene to xanthophylls is sensitive in vitro to both difunone, an inhibitor of carotene desaturation, and CPTA, an inhibitor of cyclization.  相似文献   

    11.
    Objectives: This study aims to examine the alteration in coronary haemodynamics with increasing the severity of vessel compression caused by myocardial bridging (MB).

    Methods: Angiography and intravascular ultrasound were performed in 10 patients with MB with varying severities of systolic compression in the left anterior descending (LAD) artery. Computer models of MB were developed and transient computational fluid dynamics simulations were performed to derive distribution of blood residence time and shear stress.

    Results: With increasing the severity of bridge compression, a decreasing trend was observed in the shear stress over proximal segment whereas an increasing trend was found in the shear stress over bridge segment. When patients were divided into 2 groups based on the average systolic vessel compression in the whole cohort (%CRave = 27.38), patients with bridges with major systolic compression (>%CRave) had smaller shear stress and higher residence time in the proximal segment compared to those with bridges with minor systolic compression (<%CRave) (0.37?±?0.23 vs 0.69?±?0.29?Pa and 0.0037?±?0.0069 vs 0.022?±?0.0094?s). In contrast, patients with bridges with major systolic compression had greater shear stress in the bridge segment compared to those with bridges with minor systolic compression (2.49?±?2.06 vs 1.13?±?0.89?Pa). No significant difference was found in the distal shear stress of patients with bridges with major and minor systolic compression.

    Conclusion: Our findings revealed a direct relationship between the severity of systolic compression of MB and haemodynamic perturbations in the proximal segment such that the increased systolic vessel compression was associated with decreased shear stress and increased blood residence time.  相似文献   


    12.
    Gram-negative bacterial quorum sensing is mainly regulated by an extracellularly produced N-acylhomoserine lactone (AHL). AHL consists of a lactone ring and an acyl chain, which generally varies from C4 to C18 in length and affords species-specific variety. In this study, we developed an ultra-high performance liquid chromatography tandem mass spectrometry system and detected two kinds of long chain AHLs with chain length C20 from the reverse-phase thin layer chromatography-fractionated cultured supernatant of the marine photosynthetic bacterium Rhodovulum sulfidophilum. By fragmentation search analysis to detect compounds with a homoserine lactone ring moiety for data dependent acquisition, a minor AHL, presumed to be 3-OH-C18-homoserine lactone (HSL), was also found. Among the detected C20-HSLs, 3-OH-C20-HSL was structurally identified and 3-OH-C20:1-HSL was strongly suggested. To our knowledge, this is the first report to show a novel AHL with the longest C20 acyl side chain found to date.

    Abbreviations: AGC: automatic gain control; AHL: N-acylhomoserine lactone; CD: cyclodextrin; CID: collision induced dissociation; DDA: data dependent acquisition; EPI: enhanced product ion; FISh: fragment ion search; HCD: high energy collisional dissociation; HSL: homoserine lactone; IT: injection time; LC: liquid chromatography; MS: mass spectrometry; PRM: parallel reaction monitoring; RP: reverse phase; SRM: selected reaction monitoring; TLC: thin layer chromatography; UHPLC: ultra high performance liquid chromatography  相似文献   


    13.
    G-quadruplex-binders have the plausible potential to act as anticancer agents. Herein, the mode of binding of a synthesized fluorenyl derivative of β-cyclodextrin with a duplex and G-quadrulex DNAs has been investigated. Moreover, the loading of the well-known G-quadruplex binder, berberine, in the β-cyclodextrin derivative using 2-dimensional rotating-frame Overhauser effect spectroscopy is studied. The intensity of proton NMR signals is weakened on the β-cyclodextrin derivative’s interaction with the quadruplexes. Binding constants are reported for each binding of the ligands to calf thymus DNA, kit22, telo24, and myc22 employing fluorescence spectroscopy. A general trend of fluorescence response (quenching) on the β-cyclodextrin derivative to the DNAs is modified when the berberine molecule is loaded in the host structure. Despite berberine binds to the macromolecular target strongly, its host-guest association with the cavity of β-cyclodextrin diminishes the binding strength. A significant difference between the binding strengths of the ligands with duplex and quadruplex structures is observed.

    Communicated by Ramaswamy H. Sarma  相似文献   


    14.
    Background: Anoxic brain injury is the primary cause of death after resuscitation from out-of-hospital cardiac arrest (OHCA) and prognostication is challenging. The aim of this study was to evaluate the potential of two fragments of tau as serum biomarkers for neurological outcome.

    Methods: Single-center sub-study of 171 patients included in the Target Temperature Management (TTM) Trial randomly assigned to TTM at 33?°C or TTM at 36?°C for 24?h after OHCA. Fragments (tau-A and tau-C) of the neuronal protein tau were measured in serum 24, 48 and 72?h after OHCA. The primary endpoint was neurological outcome.

    Results: Median (quartile 1 – quartile 3) tau-A (ng/ml) values were 58 (43–71) versus 51 (43–67), 72 (57–84) versus 71 (59–82) and 76 (61–92) versus 75 (64–89) for good versus unfavourable outcome at 24, 48 and 72?h, respectively (pgroup = 0.95). Median tau C (ng/ml) values were 38 (29–50) versus 36 (29–49), 49 (38–58) versus 48 (33–59) and 48 (39–59) versus 48 (36–62) (pgroup = 0.95). Tau-A and tau-C did not predict neurological outcome (area under the receiver-operating curve at 48?h; tau-A: 0.51 and tau-C: 0.51).

    Conclusions: Serum levels of tau fragments were unable to predict neurological outcome after OHCA.  相似文献   


    15.
    Xanthophyll carotenoids, such as lutein, zeaxanthin and β-cryptoxanthin, may provide potential health benefits against chronic and degenerative diseases. Investigating pathways of xanthophyll metabolism are important to understanding their biological functions. Carotene-15,15′-monooxygenase (CMO1) has been shown to be involved in vitamin A formation, while recent studies suggest that carotene-9′,10′-monooxygenase (CMO2) may have a broader substrate specificity than previously recognized. In this in vitro study, we investigated baculovirus-generated recombinant ferret CMO2 cleavage activity towards the carotenoid substrates zeaxanthin, lutein and β-cryptoxanthin. Utilizing HPLC, LC–MS and GC–MS, we identified both volatile and non-volatile apo-carotenoid products including 3-OH-β-ionone, 3-OH-α-ionone, β-ionone, 3-OH-α-apo-10′-carotenal, 3-OH-β-apo-10′-carotenal, and β-apo-10′-carotenal, indicating cleavage at both the 9,10 and 9′,10′ carbon–carbon double bond. Enzyme kinetic analysis indicated the xanthophylls zeaxanthin and lutein are preferentially cleaved over β-cryptoxanthin, indicating a key role of CMO2 in non-provitamin A carotenoid metabolism. Furthermore, incubation of 3-OH-β-apo-10′-carotenal with CMO2 lysate resulted in the formation of 3-OH-β-ionone. In the presence of NAD+, in vitro incubation of 3-OH-β-apo-10′-carotenal with ferret hepatic homogenates formed 3-OH-β-apo-10′-carotenoic acid. Since apo-carotenoids serve as important signaling molecules in a variety of biological processes, enzymatic cleavage of xanthophylls by mammalian CMO2 represents a new avenue of research regarding vertebrate carotenoid metabolism and biological function.  相似文献   

    16.
    17.
    The carotenoids characteristic of lichen species of the subgenera Cladina and Cladonia are β-cryptoxanthin, zeaxanthin and lutein epoxide  相似文献   

    18.
    We studied the effects of temperature, carbon dioxide and abscisic acid on mung bean (Vigna radiata). Plants were grown under 26/22°C or 32/28°C (16?h?light/8?h?dark) at 400 or 700?μmol?mol?1 CO2 and received ABA application of 0 or 100?μl (10?μg) every other day for three weeks, after eight days of initial growth, in growth chambers. We measured 24 parameters. As individual factors, in 16 cases temperature; in 8 cases CO2; in 9 cases ABA; and as interactive factors, in 4 cases, each of temperature?×?CO2, and CO2?×?ABA; and in 2 cases, temperature?×?ABA were significant. Higher temperatures increased growth, aboveground biomass, growth indices, photochemical quenching (qP) and nitrogen balance index (NBI). Elevated CO2 increased growth and aboveground biomass. ABA decreased growth, belowground biomass, qP and flavonoids; increased shoot/root mass ratio, chlorophyll and NBI; and had little role in regulating temperature–CO2 effects.

    Abbreviations: AN: net CO2 assimilation; E: transpiration; Fv/Fm: maximum quantum yield of PSII; gs: stomatal conductance; LAR: leaf area ratio; LMA: leaf mass per area; LMR: leaf mass ratio;φPSII: effective quantum yield of PSII; qNP: non-photochemical quenching; qP: photochemical quenching; SRMR: shoot to root mass ratio; WUE: water use efficiency  相似文献   


    19.
    Context: Stomach ulcers are the common gastrointestinal disorders worldwide.

    Objective: This study aimed to investigate the therapeutic impact of Pulicaria crispa aerial parts ethanol extract against gastric ulcer in rats.

    Materials and methods: Ulcer was induced by one oral dose of ethanol (0.5?ml/100g body weight) on 24?hours empty stomach, then the plant extract (500?mg/kg b.wt.) was orally administered daily for one week. Ranitidine (100?mg/kg b.wt.); as a reference drug was evaluated. Stomach acidity and volume, as well as lesion counts were measured. Levels of malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD) were estimated. Assay of different marker enzymes; succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), glucose-6-phosphatase (G-6-Pase), acid phosphatase (AP) and 5′-nucleotidase (5′NT) were determined. Interlukin-10 (IL-10), intracellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor alpha (TNF-α) were also determined. Stomach histopathological assessment was detected.

    Results: Gastric ulcer showed drastic changes in oxidative stress, cell organelles and inflammatory markers. These biomarkers served as good tools to identify the presence of gastric ulcer. Treatment with P. crispa recorded amelioration in most parameters exceeding the auto healing effect.

    Conclusion: Healing potency of P. crispa is possibly related to its content of glycosides, coumarins, flavonoids, tannins, sterols and triterpenes.  相似文献   


    20.
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