Production of monoclonal antibody against porcine adipocyte plasma membrane proteins to explore a new way of controlling body fat deposition and improving carcass quality is discussed in this article. Membrane protein...Production of monoclonal antibody against porcine adipocyte plasma membrane proteins to explore a new way of controlling body fat deposition and improving carcass quality is discussed in this article. Membrane proteins of pig adipocyte plasma membrane proteins were extracted with the help of sucrose density gradient centrifugation, and two kinds of proteins were obtained. The monoclonal antibody (designated 3B2 and 3F3) of IgG1 and IgG2b subclass against adipocyte membrane proteins were produced by immunization, with adipocyte membrane proteins as an antigen, and its titer was 1:105 detected by enzyme-linked immunoadsorbent assay (ELISA). The cell strains were identified by analyzing the number of chromosomes, the heat stability, the acid and alkali, the types and subtypes of immnoglobulin, and its peculiarities and affinities. Through identification, the chromosome number of hybridoma cell strains was from 80 to 100 and the strains formed good hybridomas colonies. The strains' affinity constants were 4.63 × 10^9 and 3.75 × 10^9 (mol L^-1)-1, respectively. At the same time, the McAb secreted was stable to environmental factors, such as, temperature, acid, alkali and so on. The monoclonal antibodies had been obtained and their specificity to porcine adipocyte plasma membrane proteins had been identified.展开更多
A symptom of chilling injury is development of water deficit in shoots, resulting from an imbalance of water transport and transpiration. In this work, two rice varieties (Oryza sativa L. var. Wasetoitsu and Somewake...A symptom of chilling injury is development of water deficit in shoots, resulting from an imbalance of water transport and transpiration. In this work, two rice varieties (Oryza sativa L. var. Wasetoitsu and Somewake) seedlings were chilled at 7 ℃, followed by recovery at 28 ℃. Based on the growth phenotype and electrolyte leakage tests, Somewake was shown to be a chilling-tolerant variety, and Wasetoitsu a chilling-sensitive one. The chilling stress reduced markedly the relative water content (RWC) of leaves, accumulative transpiration and osmotic root hydraulic conductivity (Lp) in both varieties. But when retumed to 28 ℃, the water relation balance of Somewake recovered better. The mRNA expression profile of all the 11 plasma membrane intrinsic proteins (PIPs), a subgroup of aquaporins, was subsequently determined by real-time reverse transcription (RT)-PCR with TaqMan-minor grove binder (MGB) probes derived from rice var. Nipponbare during chilling treatment and recovery. Most of the PIP genes was down-regulated at the low temperature, and recovered at the warm temperature. The relative expression of some PIPs in both Somewake and Wasetoitsu decreased in parallel during the chilling. However during the recovery, the relative expression of OsPIP1;1, OsPIP2;1, OsPIP2;7 in shoots and OsPIP1:1, OsPIP2:1 in roots were significantly higher in Somewake than Wasetoitsu. This supports the role of PIPs in re-establishing water balance after chilling conditions. We discuss the diversified roles played by members of the aquaporin PIP subfamily in plant chilling tolerance depending on aquaporin isoforms, plant tissue and the stage of chilling duration.展开更多
Proteomic characterization of plasma is critical for the development of novel pharmacodynamic biomarkers.However,the vast dynamic range renders the profiling of proteomes extremely challenging.Here,we synthesized zeol...Proteomic characterization of plasma is critical for the development of novel pharmacodynamic biomarkers.However,the vast dynamic range renders the profiling of proteomes extremely challenging.Here,we synthesized zeolite NaY and developed a simple and rapid method to achieve comprehensive and deep profiling of the plasma proteome using the plasma protein corona formed on zeolite NaY.Specifically,zeolite NaY and plasma were co-incubated to form plasma protein corona on zeolite NaY(NaY-PPC),followed by conventional protein identification using liquid chromatography-tandem mass spectrometry.NaY was able to significantly enhance the detection of low-abundance plasma proteins,minimizing the“masking”effect caused by high-abundance proteins.The relative abundance of middleand low-abundance proteins increased substantially from 2.54%to 54.41%,and the top 20 highabundance proteins decreased from 83.63%to 25.77%.Notably,our method can quantify approximately 4000 plasma proteins with sensitivity up to pg/mL,compared to only about 600 proteins identified from untreated plasma samples.A pilot study based on plasma samples from 30 lung adenocarcinoma patients and 15 healthy subjects demonstrated that our method could successfully distinguish between healthy and disease states.In summary,this work provides an advantageous tool for the exploration of plasma proteomics and its translational applications.展开更多
AIM:To find the significant altered proteins in agerelated macular degeneration(AMD)patients as potential biomarkers of AMD.METHODS:A comparative analysis of the protein pattern of AMD patients versus healthy controls...AIM:To find the significant altered proteins in agerelated macular degeneration(AMD)patients as potential biomarkers of AMD.METHODS:A comparative analysis of the protein pattern of AMD patients versus healthy controls was performed by means of proteomic analysis using twodimensional gel electrophoresis followed by protein identification with MALDI TOF/TOF mass spectrometry.RESULTS:We identified 28 proteins that were significantly altered with clinical relevance in AMD patients.These proteins were involved in a wide range of biological functions including immune responses,growth cytokines,cell fate determination,wound healing,metabolism,and anti-oxidance.CONCLUSION:These results demonstrate the capacity of proteomic analysis of AMD patient plasma.In addition to the utility of this approach for biomarker discovery,identification of alterations in endogenous proteins in the plasma of AMD patient could improve our understanding of the disease pathogenesis.展开更多
Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is k...Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results.展开更多
The wheat roots membrane separates the cell from the environment around it and encloses the cell contents. The pro-tein secondary structure and thermal stability of the plasma membrane of wheat root have been characte...The wheat roots membrane separates the cell from the environment around it and encloses the cell contents. The pro-tein secondary structure and thermal stability of the plasma membrane of wheat root have been characterized in D2O buffer from 20°C to 90°C by Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). Quantitative analysis of the amide I band (1700 - 1600 cm–1) showed that the plasma membrane proteins contains 41% α-helix, 16% β-sheet, 18% turn, and 25% disorder structures at 20°C. At elevated temperatures from 25°C up to 90°C, the α-helix and the β-sheet structure unfold into turns and the disorder structure, with a major conformational transition occurring at 50°C. There is a rapid decline in H+-ATPase activity of plasma membrane from 35°C to 55°C and it remain very low level H+-ATPase activity of PM from 55°C to 90°C. Therefore the protein conformational transition was one of reasons of loses H+-ATPase activity of plasma membrane.展开更多
The objectives of this study were to explore whether heparin-binding proteins, separated by fast protein liquid chromatography from boar seminal plasma influence the release of prostaglandins F2α, (PGF2α), E2 (PGE2)...The objectives of this study were to explore whether heparin-binding proteins, separated by fast protein liquid chromatography from boar seminal plasma influence the release of prostaglandins F2α, (PGF2α), E2 (PGE2) and interleukin-6 (IL-6) by porcine endometrial and cervical cells and even bovine endometrial cells. In Experiment I, we showed that release of PGF2α by endometrial epithelial, endometrial stromal and cervical stromal cells to the medium was inhibited (p α (TNFα) stimulated release of IL-6 by endometrial and cervical stromal cells after 24 h incubation, but in the presence of heparin-binding proteins, this stimulation was attenuated. Release of PGF2α by cryopreserved (Experiment II) and primary (Experiment III) cervical stromal cells was significantly inhibited after 3 h incubation with 66 - 95.4 μg of heparin- binding proteins. A significant inhibition of PGE2 release by cryopreserved and primary cervical stromal cells was already achieved after incubation with 16.5 - 23.9 μg of heparin-binding proteins. The release of IL-6 by cryopreserved cells was stimulated after 3 h incubation with heparin- binding proteins in a dose dependent manner in contrast to the release of IL-6 by freshly isolated cervical stromal cells. We also found (Experiment IV) that porcine heparin-binding seminal plasma proteins inhibited release of PGF2α and stimulated release of IL-6 by bovine endometrial epithelial cells. In conclusion, a group of heparin-binding proteins separated by fast protein liquid chromatography from boar seminal plasma inhibit PGF2α, PGE2 and stimulate IL-6 release by porcine endometrial and cervical cells and even by bovine endometrial cells. Thus, these proteins have a similar effect as the entire seminal plasma.展开更多
We examined the effects of dietary proso-millet protein on plasma levels of high-density lipoprotein (HDL) cholesterol in different rats from animals reported in our previous studies. The results showed also, in this ...We examined the effects of dietary proso-millet protein on plasma levels of high-density lipoprotein (HDL) cholesterol in different rats from animals reported in our previous studies. The results showed also, in this animal, that the ingestion of the millet protein elevates plasma levels of HDL-cholesterol like our earlier works. Taking into account the anti-atherogenic function of HDL, therefore, the millet protein would be useful as a new food ingredient which has the function that regulates cholesterol metabolism展开更多
BACKGROUND Gestational diabetes mellitus(GDM)is a concern due to its rapid increase in incidence in recent years.AIM To investigate the correlation and predictive value of serum pregnancyassociated plasma protein A(PA...BACKGROUND Gestational diabetes mellitus(GDM)is a concern due to its rapid increase in incidence in recent years.AIM To investigate the correlation and predictive value of serum pregnancyassociated plasma protein A(PAPP-A),triglyceride(TG),and 25-hydroxyvitamin D[25-(OH)D]with GDM in early pregnancy.METHODS A total of 99 patients in early pregnancy admitted to Peking University International Hospital from November 2015 to September 2017 were included,and underwent a fasting glucose test and oral glucose tolerance test screening at 24-28 wk of pregnancy.Of these cases with GDM,51 were assigned to group A and the remaining 48 cases without GDM were enrolled in group B.Serum PAPP-A,TG and 25-(OH)D in the two groups were compared and their correlation with blood sugar was analyzed.In addition,their diagnostic value in GDM was determined using receiver operating characteristic(ROC)curve analysis.RESULTS Group A had markedly lower serum PAPP-A and 25-(OH)D levels and a significantly higher serum TG level than group B,with statistical significance(P<0.05).Furthermore,Pearson analysis identified that PAPP-A and 25-(OH)D levels were negatively correlated with fasting blood glucose(FBG)levels(r=-0.605,P<0.001),(r=-0.597,P<0.001),while TG and FBG levels were positively correlated(r=0.628,P<0.001).The sensitivity,specificity,area under the curve(AUC)and optimal cut-off value of serum PAPP-A level in the diagnosis of GDM were 72.55%,82.35%,0.861 and 16.340,respectively,while the sensitivity of TG in diagnosing GDM was 86.27%,the specificity was 66.67%,the AUC was 0.813,with an optimal cut-off value of 1.796.The corresponding sensitivity,specificity,AUC and optimal cut-off value of serum 25-(OH)D were 64.71%,70.59%,0.721 and 23.140,respectively.Moreover,multivariate logistic regression analysis revealed that FBG,vascular endothelial growth factor,Flt-1,serum PAPP-A,TG,and 25-(OH)D were related risk factors leading to GDM in patients.CONCLUSION Serum PAPP-A,TG,and 25-(OH)D levels are all correlated with blood glucose changes in GDM,and are independent factors affecting the occurrence of GDM and have certain value in the diagnosis of GDM.展开更多
Fresh blood of Tibetan sheep was subjected to protein separation and spray drying, and the effects of drying process on water content, yield and nitrogen soluble index of plasma powder from blood of Tibetan sheep were...Fresh blood of Tibetan sheep was subjected to protein separation and spray drying, and the effects of drying process on water content, yield and nitrogen soluble index of plasma powder from blood of Tibetan sheep were investigated. The results showed that the optimum separation parameters were a centrifugal speed at 6 000 r/min, centrifugal time of 20 min, a mass fraction of dry matter of 20%, an inlet air temperature at 180 ℃ and a feed rate at 400 ml/h, under which the plasma protein was a pale yellow powdery solid, indicating a good separation effect.展开更多
The present study recruited 193 patients with ischemic cerebrovascular disease from Inpatient and Outpatient Departments at the Affiliated Hospital of Qingdao University Medical College, China from August 2008 to May ...The present study recruited 193 patients with ischemic cerebrovascular disease from Inpatient and Outpatient Departments at the Affiliated Hospital of Qingdao University Medical College, China from August 2008 to May 2010, as well as 120 healthy volunteers from the Medical Examination Center at the Affiliated Hospital of Qingdao University Medical College, China, who served as controls for this study. Patients and control subjects were from the Han population in northern China. Enzyme- linked immunosorbent assay analysis revealed increased levels of serum pregnancy-associated plasma protein-A (PAPP-A) in ischemic cerebrovascular disease patients compared with healthy controls. In addition, the patients exhibited greater frequency of genotype CC and C alleles in a missense A/C (Tyr/Ser) polymorphism (dbSNP: rs7020782) of exon 14 in the PAPP-A gene. Multiple-factor logistic regression analysis on correction of age, gender, history of smoking, hypertension, diabetes mellitus, hypercholesteremia, and ischemic stroke family history showed that the risk for ischemic cerebrovascular disease in the population without the A allele at the A/C genetic locus in exon 14 of the PAPP-A was 2-folds greater than the population expressing the A allele. These experimental findings suggested that ischemic cerebrovascular disease correlated with the C allele in exon 14 of PAPP-A. In addition, the A allele is likely a protective gene; individuals carrying the A allele were less prone to ischemic cerebrovascular disease compared with individuals without the A allele.展开更多
BACKGROUND: Thrombus precursor protein (TpP) is the index of thrombus activity level, and it is also early referencing index in detecting thrombus diseases. OBJECTIVE: To dynamically observe the changes of TpP lev...BACKGROUND: Thrombus precursor protein (TpP) is the index of thrombus activity level, and it is also early referencing index in detecting thrombus diseases. OBJECTIVE: To dynamically observe the changes of TpP level in blood plasma of patients with acute cerebral infarction at different time after onset, and to compare the differences of plasma TpP level between patients with acute cerebral infarction and healthy persons who received health examination. DESIGN: Controlled observation SETTING: Department of Neurology, Affiliated Hospital of Xuzhou Medical College PARTICIPANTS: Totally 58 patients with acute cerebral infarction who received the treatment in the Department of Neurology, Affiliated Hospital of Xuzhou Medical College between September 2004 and March 2005 were recruited in this study. They all met the diagnostic criteria revised by the 4^th National Conference of Cerebrovascular Disorders in 1995 and were diagnosed by clinical and skull CT and (or) MRI examinations. The patients included 33 male and 25 female aged from 36 to 87 years. Time to onset 〈 6 hours, 6 to 11 hours, 12 to 23 hours, 24 to 48 hours and 〉 48 hours were found in 10,11,14,10 and 13 patients respectively. Another 51 persons who homeochronously received the health body examination in our hospital were recruited, including 34 male and 17 female, aged 38 to 85 years, serving as control group. Patients with cardio-cerebrovascualr diseases or liver and kidney diseases were excluded. All the involved subjects were informed of the detected items. METHODS: About 4 mL venous blood was respectively taken from patients admitted to the hospital within 6 hours, 6 toll hours, 12 to 23 hours, 24 to 48 hours and more then 48 hours after onset, and healthy persons when receiving health examination. The level of TpP in blood plasma was measured with enzymelinked immunosorbent assay. MAIN OUTCOME MEASURES: ① Comparison of the level of plasma TpP between patients and controls;② Comparison of the level of plasma TpP of patients with acute cerebral infarction at different time after onset. RESULTS: Totally 58 patients with acute cerebral infarction and 51 persons who received health examination participated in the result analysis. ①Comparison of plasma TpP level between patients and controls: The plasma TpP level of patients with acute cerebral infarction was significantly higher than that of control group [(16.12±3.28)vs (5.38±1.36) mg/L, t= 20.993, P〈 0.01 ]. ② Comparison of plasma TpP level of patients with acute cerebral infarction at different time after onset: The level of plasma TpP was (12.06±3.06) mg/L within 6 hours, (15.11±3.42) mg/L at 6 to 11 hours, (20.63±4.05) mg/L at 12 to 23 hours, (16.15±3.50) mg/L at 24 to 48 hours and (11.88±3.11) mg/L at more than 48 hours after onset. It increased from the 6^th hour, reached the peak at the 12^th to 23^rd hours, maintained at very high level at the 48= hour and then gradually decreased and recovered to the level within 6 hours after onset. The level of plasma TpP of patients with acute cerebral infarction was signiticantly higher at the 12^th to 23^rd hours after onset and the 24^th to 48^th hours after onset than within 6 hours after onset (t = 13.385, P 〈 0.05). CONCLUSION: ①The level of plasma TpP of patients with acute cerebral infarction is significantly higher than that of persons who received health examination.② Plasma TpP levels of patients with acute cerebral infarction change in wave manner at the different time after onset.展开更多
Background: The protein/energy ratio is important for the production performance and utilization of available feed resources by animals. Increased protein consumption by mammals leads to elevated feed costs and incre...Background: The protein/energy ratio is important for the production performance and utilization of available feed resources by animals. Increased protein consumption by mammals leads to elevated feed costs and increased nitrogen release into the environment. This study aimed to evaluate the effects of dietary protein/energy ratio on the growth performance, carcass traits, meat quality, and plasma metabolites of pigs of different genotypes. Methods: Bama mini-pigs and Landrace pigs were randomly assigned to two dietary treatment groups (Chinese conventional diet with low protein/energy ratio or National Research Council diet with high protein/energy ratio; n = 24 per treatment) in a 2 x 2 factorial arrangement. Blood and muscle samples were collected at the end of the nursery, growing, and finishing phases. Results: We observed significant interactions (P 〈 0.05) between breed and diet for total fat percentage, intramuscular fat (IMF) content, protein content in biceps femoris (BF) muscle, and plasma urea nitrogen (UN) concentration in the nursery phase; for average daily gain (ADG), average daily feed intake (ADFI), dry matter, IMF content in psoas major (PM) muscle, and plasma total protein and albumin concentrations in the growing phase; and for drip loss and plasma UN concentration in the finishing phase. Breed influenced (P 〈 0.05) growth performance, carcass traits, and meat quality, but not plasma metabolites. Throughout the trial, Landrace pigs showed significantly higher (P 〈 0.0_5) ADG, ADFI, dressing percentage, lean mass rate, and loin-eye area than did Bama mini-pigs, but significantly lower (P 〈 0.0.5) feed/gain ratio, fat percentage, backfat thickness, and IMF content. Dietary protein/energy ratio influenced the pH value, chemical composition of BF and PM muscles, and plasma activities of glutamic-pyruvic transaminase and gamma-glutamyl transpeptidase, and plasma concentration of UN. Conclusions: Compared with Landrace pigs, Bama mini-pigs showed slower growth and lower carcass performance, but had better meat quality. Moreover, unlike Landrace pigs, the dietary protein/energy ratio did not affect the growth performance of Bama mini-pigs. These results suggest that, in swine production, low dietary protein/energy ratio may be useful for reducing feed costs and minimizing the adverse effects of ammonia release into the environment.展开更多
A simple and selective ultra performance liquid chromatography--electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) assay was developed for the determination of the human plasma protein binding of four...A simple and selective ultra performance liquid chromatography--electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) assay was developed for the determination of the human plasma protein binding of four bioactive ftavonoids (such as orientin and vitexin) in Polygonum orientale. Protein precipitation was used for sample preparation. Equilibrium dialysis technique was applied to determine the plasma protein binding under physiological conditions. The separation was achieved through a Waters C i s column with a mobile phase composed of 0.1% formic acid in acetonitrile and 0.1% aqueous formic acid using step gradient elution at a flow rate of 0.35 mL/min. A Waters ACQUITYTM TQD system was operated under the multiple reaction monitoring (MRM) mode of positive electrospray ionization. All of the recovery, precision, accuracy and stability of the method met the requirements. Good correlations (r 〉 0.99) of the four compounds were found, which suggested that these compounds can be simultaneously determined with acceptable accuracy. Results showed that the plasma protein bindings of the four bioactive flavonoids were in the range of 74-89% over the six concentrations studied. The binding parameters containing protein binding affinity, protein binding dissociation constant, and protein binding site were studied. The maximum ability to bind with protein was also determined in the assay in order to understand the drug-protein binding of each compound better.展开更多
The human plasma protein binding of water soluble flavonoids in the peels of five spices of citrus fruits was studied by ultrafiltration combined with HPLC.The flavonoids were extracted separately by hot and cold wate...The human plasma protein binding of water soluble flavonoids in the peels of five spices of citrus fruits was studied by ultrafiltration combined with HPLC.The flavonoids were extracted separately by hot and cold water,and higher total flavonoid contents were detected in the former extracts than the latter ones.All the extracts show significant scavenging abilities to both ABTS and DPPH free radicals,which indicates the health benefits of the water extracts of citrus fruits peels.For DPPH radical,the IC50values of hot extract follow as Navel orange(NO)≈Mandarin orange(MO)< Lemon(LE)< Lo tangerine(LO)< Pomelo(PO),while the rank is NO< PO<LE≈MO<LO for ABTS radical.The HPLC results reveal that the kinds and contents of the flavonoids detected in the extracts are different among the species.MO extract has the most neohesperidin dihydrochalcone of 118.76 μmol/L and quercetrin of 211.81 μmol/L of which are much more than the rest extracts.Pomelo extract has the most plentiful flavonoids of naringin with a concentration of 303.28 μmol/L.The high contents of myricetrin and dihydromyricetin which both are potent free radical scavengers may explain the highest free radical scavenging activity of the NO extract.The plasma binding rates decrease with the increasing concentrations of flavonoids,and the flavonoids having plenty hydroxyl groups on both A ring and B ring of the molecular skeleton have relative higher plasma binding rates.In addition,the plasma binding rates of flavonoids with saturated C3-C4 bond decrease significantly with the increasing concentrations.展开更多
TM-2 known as a potential antitumor drug is a novel semi-synthetic taxane derivative. As drug-protein interactions contribute to insights into pharmacokinetic and pharmacodynamic properties, we eluci- dated the bindin...TM-2 known as a potential antitumor drug is a novel semi-synthetic taxane derivative. As drug-protein interactions contribute to insights into pharmacokinetic and pharmacodynamic properties, we eluci- dated the binding of TM-2 to plasma protein. In this study, a simple, rapid and reliable method was developed and validated employing equilibrium dialysis for the separation of bound and unbound drugs and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the quantitation. Protein binding reached equilibrium within 24 h of incubation at 37 ℃. After liquid-liquid extraction with methyl tert-butyl ether, the samples were separated on Thermo Syncronis UPLC C18 (2.1 mm× 50 mm, 1.7 μm), and acquisition of mass spectrometric data was performed in multiple re- action monitoring (MRM) mode via positive electrospray ionization. The assay was linear over the concentration rang of 5-2000 nglmL The intra- and inter-day precisions were 0.1%-14.8%, and the accuracy was from -6.4% to Z0%. This assay has been successfully applied to a protein binding study of TM-2 in rat, human and beagle dog plasma. TM-2 showed high protein binding of 81.4% ± 6.5% (rat), 87.9% ± 3.6% (human) and 79.4% ± 4.0% (beagle dog). The results revealed that there was an insignificant difference among the three species.展开更多
Background: There is great interest in developing blood-based biomarkers for Alzheimer’s disease (AD);however, there is no consensus as to what blood fraction is most appropriate for analyzing particular markers. The...Background: There is great interest in developing blood-based biomarkers for Alzheimer’s disease (AD);however, there is no consensus as to what blood fraction is most appropriate for analyzing particular markers. The current study provides empirical evidence regarding how blood-based proteins vary depending on whether they are assayed in serum or plasma. Methods: Weanalyzed concentrations of 100 proteins in matched samples of serum and plasma from 39 Caucasian AD participants from the Texas Alzheimer’s Research and Care Consortium bymultiplex immunoassay. Results: Concentrations of 40 proteins were highly correlated (r2≥ 0.75) between plasma and serum while the remaining proteins were moderately to weakly correlated (r2< 0.75). Discussion: Whether plasma vs. serum is assayed can have a large impact on the observed concentration of some proteins, including several proteins that are of great interest to AD pathophysiology. The current findings may explain the significant discrepancies often times reported in the AD biomarker field.展开更多
In this work, we describe an approach of detecting biomarkers by Surface Plasmon Resonance imaging (SPRi) technique in real samples. Two C-Reactive Protein (CRP)-antibody immobilization methods were used: The first me...In this work, we describe an approach of detecting biomarkers by Surface Plasmon Resonance imaging (SPRi) technique in real samples. Two C-Reactive Protein (CRP)-antibody immobilization methods were used: The first method was based on direct physisorption of CRP-antibody onto gold surface;the second one was based on oriented CRP-antibody with protein G intermediate layer. The two developed immunosensors were tested against CRP antigen in phosphate buffer saline solution with the SPRi technique. The response of the developed immunosensors was reproducible and stable. The detection limit of 10 pg·mLǃ and 50 pg·mLǃ CRP-antigen was observed with and without protein G respectively with this technique. Moreover, the developed SPRi immunosensor was used for CRP-antigen detection in human plasma. A detection limit of 5 ng·mLǃ and 10 ng·mLǃ was obtained with and without protein G respectively. These obtained results were compared to those obtained with QCM (Quartz Crystal Microbalance) and Enzyme-Linked Immunosorbent Assay (ELISA) techniques.展开更多
Wheat (Triticum aestivum) seeds were treated with atmospheric pressure gliding arc discharge plasmas to investigate the effects on water absorption, seed germination rate, seedling growth and yield in wheat. The sur...Wheat (Triticum aestivum) seeds were treated with atmospheric pressure gliding arc discharge plasmas to investigate the effects on water absorption, seed germination rate, seedling growth and yield in wheat. The surface architectures and functionalities of the seeds were found to modify due to plasma treatments. 6 rain treatment was provided 95%-100% germination rate. For the treatment duration of 3 and 9 rain the growth activity, dry matter accumulation, leaves chlorophyll contents, longest spikes, number of spikes/spikelet and total soluble protein content in shoots were improved. The grain yield of wheat was increased ,--20% by 6 min treatment with H2O/O2 plasma with respect to control.展开更多
Surface-grafted poly(ethylene glycol) (PEG) molecules are known to prevent protein adsorption to the surface. Nitinol samples were coated under tetraglyme ECR cold plasma conditions to enhance its biocompatibility. Th...Surface-grafted poly(ethylene glycol) (PEG) molecules are known to prevent protein adsorption to the surface. Nitinol samples were coated under tetraglyme ECR cold plasma conditions to enhance its biocompatibility. The modified Nitinol surfaces were characterized by high resolution ESCA and contact angle, it was demonstrated that the deposited PEG-like coatings were built up mainly of-CH2-CH2-O- linkages in surfaces. The surface wettability of the modified Nitinol was increased compared with the control surface. Human plasma protein was adsorbed on Nitinol evaluated by SEM, the protein adsorption on modified surfaces decreased rapidly. Thus, the potential benefits of cold plasma technique will be of use to the biomedical industries improving the biocompatibility of metals.展开更多
基金The study is supported by the Natural Science Foundation of Shanxi Province, China (20011089)the Key Project of Shanxi Province, China (20031043).
文摘Production of monoclonal antibody against porcine adipocyte plasma membrane proteins to explore a new way of controlling body fat deposition and improving carcass quality is discussed in this article. Membrane proteins of pig adipocyte plasma membrane proteins were extracted with the help of sucrose density gradient centrifugation, and two kinds of proteins were obtained. The monoclonal antibody (designated 3B2 and 3F3) of IgG1 and IgG2b subclass against adipocyte membrane proteins were produced by immunization, with adipocyte membrane proteins as an antigen, and its titer was 1:105 detected by enzyme-linked immunoadsorbent assay (ELISA). The cell strains were identified by analyzing the number of chromosomes, the heat stability, the acid and alkali, the types and subtypes of immnoglobulin, and its peculiarities and affinities. Through identification, the chromosome number of hybridoma cell strains was from 80 to 100 and the strains formed good hybridomas colonies. The strains' affinity constants were 4.63 × 10^9 and 3.75 × 10^9 (mol L^-1)-1, respectively. At the same time, the McAb secreted was stable to environmental factors, such as, temperature, acid, alkali and so on. The monoclonal antibodies had been obtained and their specificity to porcine adipocyte plasma membrane proteins had been identified.
文摘A symptom of chilling injury is development of water deficit in shoots, resulting from an imbalance of water transport and transpiration. In this work, two rice varieties (Oryza sativa L. var. Wasetoitsu and Somewake) seedlings were chilled at 7 ℃, followed by recovery at 28 ℃. Based on the growth phenotype and electrolyte leakage tests, Somewake was shown to be a chilling-tolerant variety, and Wasetoitsu a chilling-sensitive one. The chilling stress reduced markedly the relative water content (RWC) of leaves, accumulative transpiration and osmotic root hydraulic conductivity (Lp) in both varieties. But when retumed to 28 ℃, the water relation balance of Somewake recovered better. The mRNA expression profile of all the 11 plasma membrane intrinsic proteins (PIPs), a subgroup of aquaporins, was subsequently determined by real-time reverse transcription (RT)-PCR with TaqMan-minor grove binder (MGB) probes derived from rice var. Nipponbare during chilling treatment and recovery. Most of the PIP genes was down-regulated at the low temperature, and recovered at the warm temperature. The relative expression of some PIPs in both Somewake and Wasetoitsu decreased in parallel during the chilling. However during the recovery, the relative expression of OsPIP1;1, OsPIP2;1, OsPIP2;7 in shoots and OsPIP1:1, OsPIP2:1 in roots were significantly higher in Somewake than Wasetoitsu. This supports the role of PIPs in re-establishing water balance after chilling conditions. We discuss the diversified roles played by members of the aquaporin PIP subfamily in plant chilling tolerance depending on aquaporin isoforms, plant tissue and the stage of chilling duration.
基金supported by the National Natural Science Foundation of China(Grant No:51773151)。
文摘Proteomic characterization of plasma is critical for the development of novel pharmacodynamic biomarkers.However,the vast dynamic range renders the profiling of proteomes extremely challenging.Here,we synthesized zeolite NaY and developed a simple and rapid method to achieve comprehensive and deep profiling of the plasma proteome using the plasma protein corona formed on zeolite NaY.Specifically,zeolite NaY and plasma were co-incubated to form plasma protein corona on zeolite NaY(NaY-PPC),followed by conventional protein identification using liquid chromatography-tandem mass spectrometry.NaY was able to significantly enhance the detection of low-abundance plasma proteins,minimizing the“masking”effect caused by high-abundance proteins.The relative abundance of middleand low-abundance proteins increased substantially from 2.54%to 54.41%,and the top 20 highabundance proteins decreased from 83.63%to 25.77%.Notably,our method can quantify approximately 4000 plasma proteins with sensitivity up to pg/mL,compared to only about 600 proteins identified from untreated plasma samples.A pilot study based on plasma samples from 30 lung adenocarcinoma patients and 15 healthy subjects demonstrated that our method could successfully distinguish between healthy and disease states.In summary,this work provides an advantageous tool for the exploration of plasma proteomics and its translational applications.
基金Supported by the Jiangsu Provincial Program of Leading Talents in Traditional Chinese Medicine(No.LJ200911)the Scientific Project Funded by Jiangsu Provincial Administration of Traditional Chinese Medicine(No.LZ11041)
文摘AIM:To find the significant altered proteins in agerelated macular degeneration(AMD)patients as potential biomarkers of AMD.METHODS:A comparative analysis of the protein pattern of AMD patients versus healthy controls was performed by means of proteomic analysis using twodimensional gel electrophoresis followed by protein identification with MALDI TOF/TOF mass spectrometry.RESULTS:We identified 28 proteins that were significantly altered with clinical relevance in AMD patients.These proteins were involved in a wide range of biological functions including immune responses,growth cytokines,cell fate determination,wound healing,metabolism,and anti-oxidance.CONCLUSION:These results demonstrate the capacity of proteomic analysis of AMD patient plasma.In addition to the utility of this approach for biomarker discovery,identification of alterations in endogenous proteins in the plasma of AMD patient could improve our understanding of the disease pathogenesis.
基金supported by the National Key Research&Development Program of China,Nos.2021YFC2501205(to YC),2022YFC24069004(to JL)the STI2030-Major Project,Nos.2021ZD0201101(to YC),2022ZD0211800(to YH)+2 种基金the National Natural Science Foundation of China(Major International Joint Research Project),No.82020108013(to YH)the Sino-German Center for Research Promotion,No.M-0759(to YH)a grant from Beijing Municipal Science&Technology Commission(Beijing Brain Initiative),No.Z201100005520018(to JL)。
文摘Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results.
文摘The wheat roots membrane separates the cell from the environment around it and encloses the cell contents. The pro-tein secondary structure and thermal stability of the plasma membrane of wheat root have been characterized in D2O buffer from 20°C to 90°C by Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). Quantitative analysis of the amide I band (1700 - 1600 cm–1) showed that the plasma membrane proteins contains 41% α-helix, 16% β-sheet, 18% turn, and 25% disorder structures at 20°C. At elevated temperatures from 25°C up to 90°C, the α-helix and the β-sheet structure unfold into turns and the disorder structure, with a major conformational transition occurring at 50°C. There is a rapid decline in H+-ATPase activity of plasma membrane from 35°C to 55°C and it remain very low level H+-ATPase activity of PM from 55°C to 90°C. Therefore the protein conformational transition was one of reasons of loses H+-ATPase activity of plasma membrane.
文摘The objectives of this study were to explore whether heparin-binding proteins, separated by fast protein liquid chromatography from boar seminal plasma influence the release of prostaglandins F2α, (PGF2α), E2 (PGE2) and interleukin-6 (IL-6) by porcine endometrial and cervical cells and even bovine endometrial cells. In Experiment I, we showed that release of PGF2α by endometrial epithelial, endometrial stromal and cervical stromal cells to the medium was inhibited (p α (TNFα) stimulated release of IL-6 by endometrial and cervical stromal cells after 24 h incubation, but in the presence of heparin-binding proteins, this stimulation was attenuated. Release of PGF2α by cryopreserved (Experiment II) and primary (Experiment III) cervical stromal cells was significantly inhibited after 3 h incubation with 66 - 95.4 μg of heparin- binding proteins. A significant inhibition of PGE2 release by cryopreserved and primary cervical stromal cells was already achieved after incubation with 16.5 - 23.9 μg of heparin-binding proteins. The release of IL-6 by cryopreserved cells was stimulated after 3 h incubation with heparin- binding proteins in a dose dependent manner in contrast to the release of IL-6 by freshly isolated cervical stromal cells. We also found (Experiment IV) that porcine heparin-binding seminal plasma proteins inhibited release of PGF2α and stimulated release of IL-6 by bovine endometrial epithelial cells. In conclusion, a group of heparin-binding proteins separated by fast protein liquid chromatography from boar seminal plasma inhibit PGF2α, PGE2 and stimulate IL-6 release by porcine endometrial and cervical cells and even by bovine endometrial cells. Thus, these proteins have a similar effect as the entire seminal plasma.
文摘We examined the effects of dietary proso-millet protein on plasma levels of high-density lipoprotein (HDL) cholesterol in different rats from animals reported in our previous studies. The results showed also, in this animal, that the ingestion of the millet protein elevates plasma levels of HDL-cholesterol like our earlier works. Taking into account the anti-atherogenic function of HDL, therefore, the millet protein would be useful as a new food ingredient which has the function that regulates cholesterol metabolism
文摘BACKGROUND Gestational diabetes mellitus(GDM)is a concern due to its rapid increase in incidence in recent years.AIM To investigate the correlation and predictive value of serum pregnancyassociated plasma protein A(PAPP-A),triglyceride(TG),and 25-hydroxyvitamin D[25-(OH)D]with GDM in early pregnancy.METHODS A total of 99 patients in early pregnancy admitted to Peking University International Hospital from November 2015 to September 2017 were included,and underwent a fasting glucose test and oral glucose tolerance test screening at 24-28 wk of pregnancy.Of these cases with GDM,51 were assigned to group A and the remaining 48 cases without GDM were enrolled in group B.Serum PAPP-A,TG and 25-(OH)D in the two groups were compared and their correlation with blood sugar was analyzed.In addition,their diagnostic value in GDM was determined using receiver operating characteristic(ROC)curve analysis.RESULTS Group A had markedly lower serum PAPP-A and 25-(OH)D levels and a significantly higher serum TG level than group B,with statistical significance(P<0.05).Furthermore,Pearson analysis identified that PAPP-A and 25-(OH)D levels were negatively correlated with fasting blood glucose(FBG)levels(r=-0.605,P<0.001),(r=-0.597,P<0.001),while TG and FBG levels were positively correlated(r=0.628,P<0.001).The sensitivity,specificity,area under the curve(AUC)and optimal cut-off value of serum PAPP-A level in the diagnosis of GDM were 72.55%,82.35%,0.861 and 16.340,respectively,while the sensitivity of TG in diagnosing GDM was 86.27%,the specificity was 66.67%,the AUC was 0.813,with an optimal cut-off value of 1.796.The corresponding sensitivity,specificity,AUC and optimal cut-off value of serum 25-(OH)D were 64.71%,70.59%,0.721 and 23.140,respectively.Moreover,multivariate logistic regression analysis revealed that FBG,vascular endothelial growth factor,Flt-1,serum PAPP-A,TG,and 25-(OH)D were related risk factors leading to GDM in patients.CONCLUSION Serum PAPP-A,TG,and 25-(OH)D levels are all correlated with blood glucose changes in GDM,and are independent factors affecting the occurrence of GDM and have certain value in the diagnosis of GDM.
基金Supported by"123"Science and Technology Support Program from Science and Technology Department of Qinghai Province(2014-GX-136A)~~
文摘Fresh blood of Tibetan sheep was subjected to protein separation and spray drying, and the effects of drying process on water content, yield and nitrogen soluble index of plasma powder from blood of Tibetan sheep were investigated. The results showed that the optimum separation parameters were a centrifugal speed at 6 000 r/min, centrifugal time of 20 min, a mass fraction of dry matter of 20%, an inlet air temperature at 180 ℃ and a feed rate at 400 ml/h, under which the plasma protein was a pale yellow powdery solid, indicating a good separation effect.
文摘The present study recruited 193 patients with ischemic cerebrovascular disease from Inpatient and Outpatient Departments at the Affiliated Hospital of Qingdao University Medical College, China from August 2008 to May 2010, as well as 120 healthy volunteers from the Medical Examination Center at the Affiliated Hospital of Qingdao University Medical College, China, who served as controls for this study. Patients and control subjects were from the Han population in northern China. Enzyme- linked immunosorbent assay analysis revealed increased levels of serum pregnancy-associated plasma protein-A (PAPP-A) in ischemic cerebrovascular disease patients compared with healthy controls. In addition, the patients exhibited greater frequency of genotype CC and C alleles in a missense A/C (Tyr/Ser) polymorphism (dbSNP: rs7020782) of exon 14 in the PAPP-A gene. Multiple-factor logistic regression analysis on correction of age, gender, history of smoking, hypertension, diabetes mellitus, hypercholesteremia, and ischemic stroke family history showed that the risk for ischemic cerebrovascular disease in the population without the A allele at the A/C genetic locus in exon 14 of the PAPP-A was 2-folds greater than the population expressing the A allele. These experimental findings suggested that ischemic cerebrovascular disease correlated with the C allele in exon 14 of PAPP-A. In addition, the A allele is likely a protective gene; individuals carrying the A allele were less prone to ischemic cerebrovascular disease compared with individuals without the A allele.
文摘BACKGROUND: Thrombus precursor protein (TpP) is the index of thrombus activity level, and it is also early referencing index in detecting thrombus diseases. OBJECTIVE: To dynamically observe the changes of TpP level in blood plasma of patients with acute cerebral infarction at different time after onset, and to compare the differences of plasma TpP level between patients with acute cerebral infarction and healthy persons who received health examination. DESIGN: Controlled observation SETTING: Department of Neurology, Affiliated Hospital of Xuzhou Medical College PARTICIPANTS: Totally 58 patients with acute cerebral infarction who received the treatment in the Department of Neurology, Affiliated Hospital of Xuzhou Medical College between September 2004 and March 2005 were recruited in this study. They all met the diagnostic criteria revised by the 4^th National Conference of Cerebrovascular Disorders in 1995 and were diagnosed by clinical and skull CT and (or) MRI examinations. The patients included 33 male and 25 female aged from 36 to 87 years. Time to onset 〈 6 hours, 6 to 11 hours, 12 to 23 hours, 24 to 48 hours and 〉 48 hours were found in 10,11,14,10 and 13 patients respectively. Another 51 persons who homeochronously received the health body examination in our hospital were recruited, including 34 male and 17 female, aged 38 to 85 years, serving as control group. Patients with cardio-cerebrovascualr diseases or liver and kidney diseases were excluded. All the involved subjects were informed of the detected items. METHODS: About 4 mL venous blood was respectively taken from patients admitted to the hospital within 6 hours, 6 toll hours, 12 to 23 hours, 24 to 48 hours and more then 48 hours after onset, and healthy persons when receiving health examination. The level of TpP in blood plasma was measured with enzymelinked immunosorbent assay. MAIN OUTCOME MEASURES: ① Comparison of the level of plasma TpP between patients and controls;② Comparison of the level of plasma TpP of patients with acute cerebral infarction at different time after onset. RESULTS: Totally 58 patients with acute cerebral infarction and 51 persons who received health examination participated in the result analysis. ①Comparison of plasma TpP level between patients and controls: The plasma TpP level of patients with acute cerebral infarction was significantly higher than that of control group [(16.12±3.28)vs (5.38±1.36) mg/L, t= 20.993, P〈 0.01 ]. ② Comparison of plasma TpP level of patients with acute cerebral infarction at different time after onset: The level of plasma TpP was (12.06±3.06) mg/L within 6 hours, (15.11±3.42) mg/L at 6 to 11 hours, (20.63±4.05) mg/L at 12 to 23 hours, (16.15±3.50) mg/L at 24 to 48 hours and (11.88±3.11) mg/L at more than 48 hours after onset. It increased from the 6^th hour, reached the peak at the 12^th to 23^rd hours, maintained at very high level at the 48= hour and then gradually decreased and recovered to the level within 6 hours after onset. The level of plasma TpP of patients with acute cerebral infarction was signiticantly higher at the 12^th to 23^rd hours after onset and the 24^th to 48^th hours after onset than within 6 hours after onset (t = 13.385, P 〈 0.05). CONCLUSION: ①The level of plasma TpP of patients with acute cerebral infarction is significantly higher than that of persons who received health examination.② Plasma TpP levels of patients with acute cerebral infarction change in wave manner at the different time after onset.
基金supported by the National Basic Research Program of China(No.2012CB124704 and 2013CB127305)KC.Wong Education Foundation,Hong Kong
文摘Background: The protein/energy ratio is important for the production performance and utilization of available feed resources by animals. Increased protein consumption by mammals leads to elevated feed costs and increased nitrogen release into the environment. This study aimed to evaluate the effects of dietary protein/energy ratio on the growth performance, carcass traits, meat quality, and plasma metabolites of pigs of different genotypes. Methods: Bama mini-pigs and Landrace pigs were randomly assigned to two dietary treatment groups (Chinese conventional diet with low protein/energy ratio or National Research Council diet with high protein/energy ratio; n = 24 per treatment) in a 2 x 2 factorial arrangement. Blood and muscle samples were collected at the end of the nursery, growing, and finishing phases. Results: We observed significant interactions (P 〈 0.05) between breed and diet for total fat percentage, intramuscular fat (IMF) content, protein content in biceps femoris (BF) muscle, and plasma urea nitrogen (UN) concentration in the nursery phase; for average daily gain (ADG), average daily feed intake (ADFI), dry matter, IMF content in psoas major (PM) muscle, and plasma total protein and albumin concentrations in the growing phase; and for drip loss and plasma UN concentration in the finishing phase. Breed influenced (P 〈 0.05) growth performance, carcass traits, and meat quality, but not plasma metabolites. Throughout the trial, Landrace pigs showed significantly higher (P 〈 0.0_5) ADG, ADFI, dressing percentage, lean mass rate, and loin-eye area than did Bama mini-pigs, but significantly lower (P 〈 0.0.5) feed/gain ratio, fat percentage, backfat thickness, and IMF content. Dietary protein/energy ratio influenced the pH value, chemical composition of BF and PM muscles, and plasma activities of glutamic-pyruvic transaminase and gamma-glutamyl transpeptidase, and plasma concentration of UN. Conclusions: Compared with Landrace pigs, Bama mini-pigs showed slower growth and lower carcass performance, but had better meat quality. Moreover, unlike Landrace pigs, the dietary protein/energy ratio did not affect the growth performance of Bama mini-pigs. These results suggest that, in swine production, low dietary protein/energy ratio may be useful for reducing feed costs and minimizing the adverse effects of ammonia release into the environment.
基金This work was supported by the National Science Foundation of China (No. 30860366) Guizhou Province Municipal Science and Technology Project (No. 2007-6010).
文摘A simple and selective ultra performance liquid chromatography--electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) assay was developed for the determination of the human plasma protein binding of four bioactive ftavonoids (such as orientin and vitexin) in Polygonum orientale. Protein precipitation was used for sample preparation. Equilibrium dialysis technique was applied to determine the plasma protein binding under physiological conditions. The separation was achieved through a Waters C i s column with a mobile phase composed of 0.1% formic acid in acetonitrile and 0.1% aqueous formic acid using step gradient elution at a flow rate of 0.35 mL/min. A Waters ACQUITYTM TQD system was operated under the multiple reaction monitoring (MRM) mode of positive electrospray ionization. All of the recovery, precision, accuracy and stability of the method met the requirements. Good correlations (r 〉 0.99) of the four compounds were found, which suggested that these compounds can be simultaneously determined with acceptable accuracy. Results showed that the plasma protein bindings of the four bioactive flavonoids were in the range of 74-89% over the six concentrations studied. The binding parameters containing protein binding affinity, protein binding dissociation constant, and protein binding site were studied. The maximum ability to bind with protein was also determined in the assay in order to understand the drug-protein binding of each compound better.
基金Project(21176263) supported by the National Natural Science Foundation of China
文摘The human plasma protein binding of water soluble flavonoids in the peels of five spices of citrus fruits was studied by ultrafiltration combined with HPLC.The flavonoids were extracted separately by hot and cold water,and higher total flavonoid contents were detected in the former extracts than the latter ones.All the extracts show significant scavenging abilities to both ABTS and DPPH free radicals,which indicates the health benefits of the water extracts of citrus fruits peels.For DPPH radical,the IC50values of hot extract follow as Navel orange(NO)≈Mandarin orange(MO)< Lemon(LE)< Lo tangerine(LO)< Pomelo(PO),while the rank is NO< PO<LE≈MO<LO for ABTS radical.The HPLC results reveal that the kinds and contents of the flavonoids detected in the extracts are different among the species.MO extract has the most neohesperidin dihydrochalcone of 118.76 μmol/L and quercetrin of 211.81 μmol/L of which are much more than the rest extracts.Pomelo extract has the most plentiful flavonoids of naringin with a concentration of 303.28 μmol/L.The high contents of myricetrin and dihydromyricetin which both are potent free radical scavengers may explain the highest free radical scavenging activity of the NO extract.The plasma binding rates decrease with the increasing concentrations of flavonoids,and the flavonoids having plenty hydroxyl groups on both A ring and B ring of the molecular skeleton have relative higher plasma binding rates.In addition,the plasma binding rates of flavonoids with saturated C3-C4 bond decrease significantly with the increasing concentrations.
基金partly supported by the National High Technology Research and Development Program of China(No.2012AA020305)
文摘TM-2 known as a potential antitumor drug is a novel semi-synthetic taxane derivative. As drug-protein interactions contribute to insights into pharmacokinetic and pharmacodynamic properties, we eluci- dated the binding of TM-2 to plasma protein. In this study, a simple, rapid and reliable method was developed and validated employing equilibrium dialysis for the separation of bound and unbound drugs and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the quantitation. Protein binding reached equilibrium within 24 h of incubation at 37 ℃. After liquid-liquid extraction with methyl tert-butyl ether, the samples were separated on Thermo Syncronis UPLC C18 (2.1 mm× 50 mm, 1.7 μm), and acquisition of mass spectrometric data was performed in multiple re- action monitoring (MRM) mode via positive electrospray ionization. The assay was linear over the concentration rang of 5-2000 nglmL The intra- and inter-day precisions were 0.1%-14.8%, and the accuracy was from -6.4% to Z0%. This assay has been successfully applied to a protein binding study of TM-2 in rat, human and beagle dog plasma. TM-2 showed high protein binding of 81.4% ± 6.5% (rat), 87.9% ± 3.6% (human) and 79.4% ± 4.0% (beagle dog). The results revealed that there was an insignificant difference among the three species.
文摘Background: There is great interest in developing blood-based biomarkers for Alzheimer’s disease (AD);however, there is no consensus as to what blood fraction is most appropriate for analyzing particular markers. The current study provides empirical evidence regarding how blood-based proteins vary depending on whether they are assayed in serum or plasma. Methods: Weanalyzed concentrations of 100 proteins in matched samples of serum and plasma from 39 Caucasian AD participants from the Texas Alzheimer’s Research and Care Consortium bymultiplex immunoassay. Results: Concentrations of 40 proteins were highly correlated (r2≥ 0.75) between plasma and serum while the remaining proteins were moderately to weakly correlated (r2< 0.75). Discussion: Whether plasma vs. serum is assayed can have a large impact on the observed concentration of some proteins, including several proteins that are of great interest to AD pathophysiology. The current findings may explain the significant discrepancies often times reported in the AD biomarker field.
文摘In this work, we describe an approach of detecting biomarkers by Surface Plasmon Resonance imaging (SPRi) technique in real samples. Two C-Reactive Protein (CRP)-antibody immobilization methods were used: The first method was based on direct physisorption of CRP-antibody onto gold surface;the second one was based on oriented CRP-antibody with protein G intermediate layer. The two developed immunosensors were tested against CRP antigen in phosphate buffer saline solution with the SPRi technique. The response of the developed immunosensors was reproducible and stable. The detection limit of 10 pg·mLǃ and 50 pg·mLǃ CRP-antigen was observed with and without protein G respectively with this technique. Moreover, the developed SPRi immunosensor was used for CRP-antigen detection in human plasma. A detection limit of 5 ng·mLǃ and 10 ng·mLǃ was obtained with and without protein G respectively. These obtained results were compared to those obtained with QCM (Quartz Crystal Microbalance) and Enzyme-Linked Immunosorbent Assay (ELISA) techniques.
基金Partial financial support has been provided by the Ministry of Science and Technology, Republic of Bangladesh: 39.00.0000.09.06.79.2017/2/98ESBangladesh Council for Scientific and Industrial Research (BCSIR) for providing Professor Abdullah Al-Muti Sharfuddin fellowship
文摘Wheat (Triticum aestivum) seeds were treated with atmospheric pressure gliding arc discharge plasmas to investigate the effects on water absorption, seed germination rate, seedling growth and yield in wheat. The surface architectures and functionalities of the seeds were found to modify due to plasma treatments. 6 rain treatment was provided 95%-100% germination rate. For the treatment duration of 3 and 9 rain the growth activity, dry matter accumulation, leaves chlorophyll contents, longest spikes, number of spikes/spikelet and total soluble protein content in shoots were improved. The grain yield of wheat was increased ,--20% by 6 min treatment with H2O/O2 plasma with respect to control.
基金The project was supported by the National Natural Science Foundation of China(NSFC)(Grant No.19972071,50274065)subsidized by the Special Funds for Major State Basic Research Project(“973”Project)(Grant No.2002CB412704).
文摘Surface-grafted poly(ethylene glycol) (PEG) molecules are known to prevent protein adsorption to the surface. Nitinol samples were coated under tetraglyme ECR cold plasma conditions to enhance its biocompatibility. The modified Nitinol surfaces were characterized by high resolution ESCA and contact angle, it was demonstrated that the deposited PEG-like coatings were built up mainly of-CH2-CH2-O- linkages in surfaces. The surface wettability of the modified Nitinol was increased compared with the control surface. Human plasma protein was adsorbed on Nitinol evaluated by SEM, the protein adsorption on modified surfaces decreased rapidly. Thus, the potential benefits of cold plasma technique will be of use to the biomedical industries improving the biocompatibility of metals.