Citations
All
Search in:AllTitleAbstractAuthor name
Publications
(497)
Patents
Grants
Pathways
Clinical trials
Publication
Journal: Journal of Cellular Biochemistry
January/19/2021
Abstract
Lysozyme (LYZ) c-like proteins are primarily present in the testis and epididymis of male reproductive tissues. Here, we report a novel member of the c-type LYZ family, the seminal vesicle-secreted LYZ c-like protein (SVLLP). Three forms of SVLLP were purified from mouse seminal vesicle secretions and characterized as glycoproteins with the same protein core but different N-linked glycans. SVLLP is structurally similar to c-type LYZ proteins. Only one of the 20 invariant residues was altered in the consensus sequence of c-type LYZs; however, the changed residue (N53S) is one of two essential catalytic residues. LYZ activity assays demonstrated that the three glycoforms of SVLLP lacked enzyme activity. SVLLP is primarily expressed in seminal vesicles. Immunohistochemistry revealed that it occurs in the luminal fluid and mucosal epithelium of the seminal vesicles. Testosterone is not the primary regulator for its expression in the seminal vesicle. SVLLP binds to sperm and suppresses bovine serum albumin-induced sperm capacitation, inhibits the acrosome reaction, and blocks sperm-oocyte interactions in vitro, suggesting that SVLLP is a sperm capacitation inhibitor.
Keywords: decapacitation factor; lysozyme c-like protein; seminal vesicle proteins; sperm capacitation; testosterone.
Publication
Journal: Heliyon
April/22/2021
Abstract
The present study investigated the effect of polysaccharide gel (PG) extracted from the rind of durian fruit which is encapsulated with Bacillus subtilis as a feed and co-inoculation with Artemia nauplii in the induction of immune response in Danio rerio after Vibrio immersion challenge (5 days). The total RBC count, lysozyme activity test, weight, and length analysis revealed that the zebra fishes fed with the PG encapsulated probiotics had more immune induction activity, survival, and growth than the non-encapsulated groups. When the expression of the immune-related genes was measured, the studies revealed the significant upregulation (P < 0 .05) of interleukin 1 beta (Il1b), lysozyme (lyz), tumor necrosis factor-alpha (TNF-α), superoxide dismutase (SOD) genes in fish fed with PG encapsulated probiotics with A. nauplii showed an immense effect on the induction of immune response compared to other feeds.
Keywords: Artemia nauplii; Bacillus subtilis; Bioencapsulation; Danio rerio; Durian fruit; Immune gene expression; Polysaccharide gel.
Publication
Journal: International Journal of Medicinal Mushrooms
October/14/2018
Abstract
This study was conducted to investigate the effects of Lactobacillus casei and Agaricus bisporus administration, alone or in combination, on skin mucus immune parameters and the expression of selected genes related to growth, appetite, mucosal immunity, and antioxidant enzymes in zebrafish (Danio rerio). Zebrafish (n = 600) were randomly stocked in 12 aquariums and assigned to 1 of 4 treatments, which were repeated in triplicate. During a 60-day feeding trial, fish were fed experimental diets: (1) basal diet (control group); (2) basal diet + L. casei (107 colony-forming units/g; Pro group); (3) basal diet + 1% A. bisporus [mushroom powder [MP] group); and (4) basal diet + 1% A. bisporus + L. casei (107 colony-forming units/g) (MP + Pro group). The results demonstrated that oral administration of A. bisporus + L. casei significantly (P < 0.05) upregulated the expression of growth-related genes (gh and igf1). Similar results were observed for expression of mucosal immune-related genes (tnf-alpha, lyz, and il1b) and for antioxidant-related genes (sod, cat) in zebrafish fed A. bisporus + L. casei (P < 0.05). Also, nonspecific skin mucus immune parameters in the MP + Pro group were significantly (P < 0.05) higher than those in the MP, Pro, and control groups. These results also demonstrate the potential of combined administration of A. bisporus and L. casei as a beneficial feed additive in aquaculture.
Publication
Journal: Environmental Pollution
October/13/2019
Abstract
Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) has been detected in various environmental media and has been implicated as a weak mutagen or carcinogen, but whether TDCIPP can promote the progression of liver tumor remains unclear. In this study, krasV12 genetically modified zebrafish, Tg(fabp10:rtTA2s-M2; TRE2:EGFP-krasG12V), a model system in which liver tumors can be induced by doxycycline (DOX), was used to evaluate the liver tumor promotion potential of TDCIPP. Briefly, krasV12 transgenic females were exposed to 0.3 mg/L TDCIPP, 20 mg/L DOX or a binary mixture of 0.3 mg/L TDCIPP with 20 mg/L DOX, and liver size, histopathology, and transcriptional profiles of liver were determined. Treatment with TDCIPP resulted in increased liver size and caused more aggressive hepatocellular carcinoma (HCC). Compared with the exposure to DOX, TDCIPP in the presence of DOX up-regulated the expression of genes relevant with salmonella infection and the toll-like receptor signaling pathway. These results implied an occurrence of inflammatory reaction, which was sustained by the increase in the amount of infiltrated neutrophils in the liver of Tg(lyz:DsRed2) transgenic zebrafish larvae whose neutrophils were labelled by red fluorescent protein under the lysozyme C promoter. Furthermore, compared with the binary exposure of DOX and TDCIPP, treatment with a ternary mixture of TDCIPP, DOX and inflammatory response inhibitor (ketoprofen) significantly decrease the liver size and the amounts of neutrophils in the livers of kras and lyz double transgenic zebrafish larvae. Collectively, our results suggested that TDCIPP could promote the liver tumor progression by induction of hepatic inflammatory responses.
Publication
Journal: Molecular Biology Research Communications
February/19/2017
Abstract
Lactoferrin (Lf) is an iron-binding multi-functional glycoprotein which has numerous physiological functions such as iron transportation, anti-microbial activity and immune response. In this study, different in silico approaches were exploited to investigate Lf protein properties in a number of mammalian species. Results showed that the iron-binding site, DNA and RNA-binding sites, signal peptides and transferrin motifs in the Lf structure were highly conserved. Examined sequences showed three conserved motifs which were repeated twice in the Lf structure, demonstrating ancient duplication events in its gene. Also, results suggest that the functional domains in mammalian Lf proteins are Zinc finger, Tubulin/FtsZ, GTPase, α/β hydrolase and Zinc knuckle. The potential site for nucleic acid binding and the major DNA and RNA- binding sites in this protein were found in the lactoferricin (Lfc) fragment. Due to its high positive charge, Lf is able to bind a large number of compounds. Our analysis also revealed that the interactions between Lf and ITLN1, LYZ, CSN2, and CD14 proteins played an important role in the protective activities of Lf. Analysis for the prediction of secondary structures indicated that high amounts of α-helix, β-strand and β-sheet were present in Lf. The high degree of conservation among mammalian Lf proteins indicates that there is a close relationship between these proteins, reflecting their important role.
Publication
Journal: Fish and Shellfish Immunology
August/12/2021
Abstract
This study reports the effect of ulvan enriched diet on the influence of growth, changes in hemato-biochemical indices, improvement of antioxidant system, enhancement of innate-adaptive immunity and modification of immuno-antioxidant genes expression in Labeo rohita against Flavobacterium columnaris. The weight gain (WG) was significantly high (P > 0.05) in unchallenged normal and challenged fish fed with diets enriched with 25 and 50 mg kg-1 ulvan; the FCR was better (P > 0.05) when fed with 50 mg kg-1 enriched diet. In normal fish fed with or without ulvan supplementation was noted 100% survival rate (SR). In both groups, the red blood cell (RBC) and while blood cell (WBC) counts increased significantly (P > 0.05) when fed with 50 mg kg-1 ulvan diet whereas the hemoglobin (Hb) level increased significantly on being fed with 25 and 50 mg kg-1 ulvan diets. The SOD activity was enhanced significantly in both groups fed with any dose of ulvan diets whereas the MDA and GPx activity increased only with 25 and 50 mg kg-1 ulvan diets. The phagocytic (PC) activity significantly increased with any enriched diet and control diet groups while the respiratory burst (RB) activity increased only with 50 mg kg-1 ulvan diet. The alternate complement pathway (ACP), activity of lysozyme (Lyz), and immunoglobuline M (IgM) were better in both groups fed with 50 mg kg-1 ulvan diet. The SOD and GPx antioxidant gene expression were significantly high in both groups fed with any ulvan diet while the Nrf2 gene expression was high with 50 mg kg-1 ulvan diet. The IL-1β, TNFα, hepcidin, Lyz, and IgM cytokines or proteins mRNA expression were significant in both groups fed with all ulvan supplement diet whereas the β-2M expression was significant only with 50 mg kg-1 ulvan diet. The present research indicates that both L. rohita groups fed with 50 mg kg-1 ulvan diet significantly improved growth, antioxidant system, immune defense system, and immuno-antioxidant related gene expression against F. columnaris.
Keywords: Columnaris disease; Immune genes; Immunity; Rohu; Ulvan.
Publication
Journal: ACS Omega
November/13/2018
Abstract
Herein, we report a comprehensive study on the interaction of three protomeric forms of the antibacterial drug norfloxacin (nfx) with the enzymatic protein human lysozyme (lyz). Norfloxacin, having the option for two-stage acid-base equilibria, converts from cationic (nfx+) to zwitterionic (nfx±) form, followed by an anionic (nfx-) species, with increasing pH. Among these protomeric forms, lysozyme binds nfx± most robustly, whereas nfx- has a weak association and nfx+ does not show any interaction. In lysozyme, the location of the drug was ascertained by competitive binding assay with 8-anilino-1-naphthalenesulfonate, and this was further examined with molecular docking simulation. The binding process was found to be primarily governed by hydrogen bonding and van der Waals interactions. The study has further revealed that preferential binding of nfx± by the protein over nfx- led to a switchover of nfx- to nfx±; and the resulting increased population of nfx± over the other is beneficial for the pharmacological activity of the drug in terms of its accumulation in the target bacterial cells. The present study accomplishes two important objectives. It holds significance regarding the differential interaction of multiprotomeric drugs with biomolecules, such as proteins, enzymes, lipid membranes, etc., and also on such biomolecule-assisted alteration of the acid-base equilibrium and consequent bioavailability of the drug. The findings are useful from the viewpoints of dispensation, distribution, and metabolism of any prototropic drug in living systems as they encounter several biomolecules in vivo. Another importance of this work stems from the study of comparative binding responses of lysozyme toward a drug existing in multiple forms depending on its protonation states or some other chemical processes.
Publication
Journal: Romanian Journal of Morphology and Embryology
September/4/2018
Abstract
OBJECTIVE
Multiple cytokines and chemokines related to immune response, apoptosis and inflammation have been identified as molecules implicated in ulcerative colitis (UC) pathogenesis. The aim of this study was to identify the differences at gene expression level of a panel of candidate genes in mucosa from patients with active UC (UCA), patients in remission (UCR), and normal controls.
METHODS
Eleven individuals were enrolled in the study: eight UC patients (four with active lesions, four with mucosal healing) and three controls without inflammatory bowel disease (IBD) seen on endoscopy. All the individuals underwent mucosal biopsy during colonoscopy. Gene expression profile was evaluated by polymerase chain reaction (PCR) array, investigating 84 genes implicated in apoptosis, inflammation, immune response, cellular adhesion, tissue remodeling and mucous secretion.
RESULTS
Seventeen and three genes out of 84 were found significantly differentially expressed in UCA and UCR compared to controls, respectively. In particular, REG1A and CHI3L1 genes reported an up-regulation in UCA with a fold difference above 200. In UCR patients, the levels of CASP1, LYZ and ISG15 were different compared to controls. However, since a significant up-regulation of both CASP1 and LYZ was observed also in the UCA group, only ISG15 levels remained associated to the remission state.
CONCLUSIONS
ISG15, that plays a key role in the innate immune response, seemed to be specifically associated to the UC remission state. These preliminary data represent a starting point for defining the gene profile of UC in different stages in Romanian population. Identification of genes implicated in UC pathogenesis could be useful to select new therapeutic targets.
Publication
Journal: International Journal of Biological Macromolecules
November/28/2018
Abstract
Our current understanding of the biophysicochemical interactions at nano-bio interfaces is still very limited. Surface plasmon resonance (SPR) is a powerful tool for understanding the real-time kinetics of protein binding on the surface of nanoparticles (NPs) but has been least exploited for this purpose. In this study, we demonstrated the interaction of negatively charged poly lactic-co-glycolic acid (PLGA) NPs and positively charged chitosan oligosaccharide (COS)-coated PLGA NPs with two model proteins, namely bovine serum albumin (BSA) and hen egg white lysozyme (LYZ), at the physiological pH of 7.4. Various biophysical characterization techniques were employed to elucidate the influence of surface charge of NPs on protein interaction. SPR investigations revealed the binding affinity and binding kinetics involved in nanoparticle-protein interactions. These results confirmed that the affinity of both types of NPs towards positively charged LYZ was much greater than that for negatively charged BSA, which was also in accordance with the results of the adsorption studies. Our results demonstrate that the surface properties of the interacting species play a dominant role during protein-nanoparticle interactions, apart from the net charge on their individual surfaces. The information obtained from this study adds significant value to the biophysicochemical toolbox for characterization of nano-bio interactions.
Publication
Journal: Chemosphere
October/2/2017
Abstract
Mercury (Hg) is a global pollutant that causes negative health effects. In order to assess Hg-induced hepatotoxicity in fish and examine whether gender differences existed in response to Hg exposure, adult zebrafish were exposed to 0, 15 and 30 μg L-1 Hg2+ for 30 days, and histology, antioxidant status and the transcription levels of several immune-related genes were examined in the liver. Hg2+ exposure caused a dose-dependent increase in histopathological lesions of the liver, including vacuolization, parenchyma disorganization and pyknotic nucleus, and these lesions were more severe in males than in females. In females, Hg2+ exposure decreased CAT activity and its mRNA levels, while increased GSH content and the expressions of sod1, gpx1a, gstr and keap1. In males, the decrease in cat1 expression and the increase in GST activity, GSH and MDA contents as well as gpx1a, gstr, nrf2 and keap1 mRNA levels were observed in Hg2+-exposed groups, but the activities of CAT, SOD and GPX were only stimulated in the 15 μg L-1 Hg2+ group. Moreover, both in females and males, Hg2+ exposure down-regulated il-8 expression while up-regulated il-10 and lyz mRNAs. However, the down-regulation of il-1β and tnfα was detected only in males under Hg2+ treatments. Thus, our results indicated that HgCl2 exposure induced histopathological damage, oxidative stress and immunotoxicity in the liver of zebrafish. Different response patterns of histology, antioxidant status and immune defenses to Hg2+ between females and males suggested sex-dependent effects of Hg, and males showed more vulnerable to Hg2+ exposure than females.
Publication
Journal: Analytical Chemistry
November/1/2016
Abstract
In this work, an in situ growth protocol is introduced to fabricate three-dimensional graphene films (3D GFs) on gold substrates, which are successfully utilized as working electrode for electrochemical detection of nucleic acid (microRNA) and protein (lysozyme) based on a signal-on sensing mechanism. To realize the bridge between the gold substrate and graphene film, a monolayer of 4-aminothiophenol is self-assembled on the substrate, which is then served as connectors for the growth of 3D GFs on the gold substrate by the hydrothermal reduction (HR) technique. Moreover, given the excellent properties, such as enlarged surface area, strong binding strength between 3D GFs and gold substrate, and improved conductivity, the proposed 3D GF-fabricated gold substrate is readily employed to the construction of electrochemical biosensing platforms through introduction of magnetic nanoparticles (MNPs) as probe carriers. On the basis of the strand displacement reaction and specific binding between aptamer and its target, the developed biosensors achieve signal-on detection of microRNA-155 (miR-155) and lysozyme (Lyz) with high sensitivity and selectivity and further successfully applied to human serum assay. Overall, the proposed strategy for in situ growth of 3D GFs provides a powerful tool for a wide range of applications, which is not limited to electrochemical biosensors and can be extended to other areas, such as electrocatalysis and electronic energy-related systems.
Publication
Journal: Colloids and Surfaces B: Biointerfaces
March/17/2019
Abstract
Hybrid supramolecular spherical nanoassembly of hen egg white lysozyme and bovine apo α lactalbumin (SNLYZ-BLA) was prepared with a mean size of ˜55.2 nm using an optimized desolvation method via chemical crosslinking. The nanoassembly, SNLYZ-BLA demonstrated dose-dependent reactive oxygen species (ROS) mediated cytotoxicity in multiple cancer cells such as MCF-7, MDA-MB231, HeLa and MG 63. It also demonstrated high loading capacity of a phytochemical based anticancer agent, curcumin (248.8 mg/g) and target-based pH-responsive in vitro drug release with around 85.8% curcumin release observed under acidic condition. Moreover, curcumin loaded SNLYZ-BLA (SNLYZ-BLA-CUR) induced cell viability reduction in all cancer cells including mouse melanoma (B16F10) by more than 90% within 24 h. Further, SNLYZ-BLA and SNLYZ-BLA-CUR when conjugated with folic acid enhanced the cytotoxicity via folate receptor-based targeting. Both drug loading and release induced conformational change and folding reconstitution of the protein nano-assembly, respectively, which made the whole system an efficient therapeutic agent that works via a dual mode of action. We demonstrated that SNLYZ-BLA and SNLYZ-BLA-CUR were highly biocompatible in vitro. Therefore, our supramolecular protein nanoassembly loaded with curcumin could emerge as a comprehensive cancer therapeutics that acts via a strategic mode of dual therapeutic mechanisms.
Publication
Journal: Frontiers in Immunology
April/28/2021
Abstract
We recently reported that the in vitro and in vivo survivals of Rickettsia australis are Atg5-dependent, in association with an inhibited level of anti-rickettsial cytokine, IL-1β. In the present study, we sought to investigate how R. australis interacts with host innate immunity via an Atg5-dependent autophagic response. We found that the serum levels of IFN-γ and G-CSF in R. australis-infected Atg5flox/flox Lyz-Cre mice were significantly less compared to Atg5flox/flox mice, accompanied by significantly lower rickettsial loads in tissues with inflammatory cellular infiltrations including neutrophils. R. australis infection differentially regulated a significant number of genes in bone marrow-derived macrophages (BMMs) in an Atg5-depdent fashion as determined by RNA sequencing and Ingenuity Pathway Analysis, including genes in the molecular networks of IL-1 family cytokines and PI3K-Akt-mTOR. The secretion levels of inflammatory cytokines, such as IL-1α, IL-18, TNF-α, and IL-6, by R. australis-infected Atg5flox/flox Lyz-Cre BMMs were significantly greater compared to infected Atg5flox/flox BMMs. Interestingly, R. australis significantly increased the levels of phosphorylated mTOR and P70S6K at a time when the autophagic response is induced. Rapamycin treatment nearly abolished the phosphorylated mTOR and P70S6K but did not promote significant autophagic flux during R. australis infection. These results highlight that R. australis modulates an Atg5-dependent autophagic response, which is not sensitive to regulation by mTORC1 signaling in macrophages. Overall, we demonstrate that R. australis counteracts host innate immunity including IL-1β-dependent inflammatory response to support the bacterial survival via an mTORC1-resistant autophagic response in macrophages.
Keywords: Rickettsia; autophagy; innate immunity; mTOR signaling; macrophages.
Publication
Journal: Experimental Cell Research
January/10/2021
Abstract
Tumor-associated macrophages (TAM), which are found in the tumor microenvironment of solid tumors, not only mediate cancer immune evasion but also promote tumor growth. The transcription factor NF-κB, which is a crucial link between inflammation and tumors, can accelerate tumor occurrence and development. NEMO, the regulatory subunit of the IKK complex, plays a pivotal role in activating the NF-κB signaling pathway. However, the function of myeloid NEMO in the tumor microenvironment remains unclear. Here, we found that conditional knockout of NEMO in myeloid cells promoted tumor growth in a transplanted cancer mouse model. In Nemofl/fl lyz-cre+/- mice, the deletion of Nemo in myeloid cells increased the recruitment of M2 macrophages and myeloid-derived suppressor cells (MDSCs) into the tumor, reduced the expression of apoptosis-related proteins, and upregulated the expression of the chemokine receptor CCR2, thereby promoting tumor growth in vivo. Then, we showed that blocking the MCP1-CCR2 pathway could inhibit tumor growth, especially in mice with myeloid NEMO deletion. In this study, we examined the mechanism of NEMO in myeloid cells and explored the role of NEMO in the prevention and treatment of cancer.
Keywords: CCR2; NEMO; myeloid cells; tumor microenvironment.
Publication
Journal: Current Genomics
July/13/2020
Abstract
Background: Low Birth Weight (LBW) (birth weight <2.5 Kg) newborns are associated with a high risk of infection, morbidity and mortality during their perinatal period. Compromised innate immune responses and inefficient hematopoietic differentiation in term LBW newborns led us to evaluate the gene expression status of hematopoiesis.
Materials and methods: In this study, we compared our microarray datasets of LBW-Normal Birth Weight (NBW) newborns with two reference datasets to identify hematopoietic stem cells genes, and their differential expression in the LBW newborns, by hierarchical clustering algorithm using gplots and RcolorBrewer package in R.
Results: Comparative analysis revealed 108 differentially expressed hematopoiesis genes (DEHGs), of which 79 genes were up-regulated, and 29 genes were down-regulated in LBW newborns compared to their NBW counterparts. Moreover, protein-protein interactions, functional annotation and pathway analysis demonstrated that the up-regulated genes were mainly involved in cell proliferation and differentiation, MAPK signaling and Rho GTPases signaling, and the down-regulated genes were engaged in cell proliferation and regulation, immune system regulation, hematopoietic cell lineage and JAK-STAT pathway. The binding of down-regulated genes (LYZ and GBP1) with growth factor GM-CSF using docking and MD simulation techniques, indicated that GM-CSF has the potential to alleviate the repressed hematopoiesis in the term LBW newborns.
Conclusion: Our study revealed that DEHGs belonged to erythroid and myeloid-specific lineages and may serve as potential targets for improving hematopoiesis in term LBW newborns to help build up their weak immune defense against life-threatening infections.
Keywords: LBW and NBW newborns; genomics; hematopoietic-associated genes; molecular docking; neutropenia; systems genomics approach.
Publication
Journal: Chemosphere
March/21/2020
Abstract
A 98-day research was conducted to assess the influence of dietary montmorillonite (MMT) on growth and immune competence in rainbow trout (Oncorhynchus mykiss). Fish fry (mean weight: 500 ± 35 mg) were fed with four experimental diets contained MMT at levels of 0 (as control group), 1, 2 and 4%. At the end of the experiment, the survival rate and growth parameters and serum total protein and albumin levels in MMT experimental groups was higher than the control group. Regarding humoral immune responses, fish being fed with 2 and 4% MMT diets showed the greatest and the lowest serum C3, C4 and lysozyme levels, respectively. Serum alternative complement pathway activity (ACH50) in groups fed with 1 and 2% MMT supplemented diets was higher than the other groups. At the end of the challenge test with VHSV, the mortality rate reached to 28 and 20% in the control group and 4% MMT supplemented groups, respectively, whereas fish fed with 1 and 2% MMT supplemented diets showed the lowest mortality rate (2.5%) Fish fed with 1 and 2% MMT supplemented groups showed higher head kidney IL-1β and TNF-α genes expression compared to the other treatment groups. In addition, fish fed with 2% MMT-supplemented diet had the highest head kidney Lyz-2 gene expression. In summary, the results of this research suggests that supplementing diet with MMT at 1 or 2% improve growth and non-specific humoral immune responses and induce head kidney immune relate genes expression and disease resistance against VHS in O. mykiss.
Publication
Journal: European Biophysics Journal
November/13/2018
Abstract
By combining analytical ultracentrifugation (AUC) in liquid phase and scanning mobility particle sizer (SMPS) in the gas phase, additional information on the particle size and morphology has been obtained for rigid particles. In this paper, we transfer this concept to soft particles, allowing us to analyze the size and molar mass of the short side chain perfluorosulfonic acid ionomer Aquivion® in a dilute aqueous suspension. The determination of the primary size and exact molar mass of this class of polymers is challenging since they are optically transparent and due to the formation of different aggregate structures depending on the concentration and solvent properties. First, validation of AUC and SMPS measurements was carried out using the well-defined biopolymers bovine serum albumin (BSA) and lysozyme (LYZ) to confirm the reliability of the results of the two unique and independent classifying methods. Then, the ionomer Aquivion® was studied using both techniques. From the mean molar mass of 185 ± 14 kDa obtained by AUC, a mean hydrodynamic diameter of 7.6 ± 0.5 nm was calculated. The particle size obtained from SMPS (7.1 nm) agrees very well with the results from AUC showing that the molecule was transferred into the gas phase without significantly changing its structure. In conclusion, the Aquivion® is molecularly dispersed in the used aqueous buffer solution without any aggregate formation in the investigated concentration range (< 2 g l-1).
Related with
Publication
Journal: Colloids and Surfaces B: Biointerfaces
February/24/2019
Abstract
Poly(N-vinylpyrrolidone) (PVP)-modified surfaces have been shown to possess excellent protein resistance and good biocompatibility. However, PVP-modified surfaces with different molecular architectures have not been prepared, and their protein-resistant properties have not been studied. Herein, gold surfaces modified with linear PVP brush and PVP bottle-brush architectures were prepared by photoinitiated surface grafting polymerization. Ellipsometry, X-ray photoelectron spectroscopy (XPS), water contact angle, Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM) were utilized to characterize the prepared surfaces. The protein-resistant properties were investigated by a quartz crystal microbalance with dissipation (QCM-D) with bovine serum albumin (BSA), fibrinogen (Fg) and lysozyme (Lyz). Compared with the ungrafted QCM-D chips, the PVP bottle-brush-grafted chips (9.3 nm thickness) showed superior protein resistance over linear PVP brush-grafted chips (9.9 nm thickness). Furthermore, the PVP bottle-brushes reduced the levels of BSA, Fg and Lyz adsorption by 97%, 85% and 69%, respectively. Moreover, to demonstrate potential applications as functional biosensors and in the biomedical field, PVP bottle-brushes containing glycopolymer-grafted gold surfaces were fabricated. Laser scanning confocal microscopy (LSCM) demonstrated that these glycopolymer surfaces showed excellent protein resistance and specific ConA binding ability. Overall, we speculate that the data presented here can provide useful information for the development of excellent antifouling materials and functional biosensors.
Publication
Journal: Journal of Fluorescence
October/29/2017
Abstract
Fluorescence properties of N, N'-bis(salicylidene) trans 1, 2-diaminocyclohexane (H 2 L) is used to probe the anionic (SDS), cationic (CTAB) and nonionic (TX-100) micelles as well as in serum albumins (BSA and HSA) and chicken egg white lysozyme (LYZ) by steady state and picosecond time-resolved fluorescence spectroscopy. The fluorescence band intensity was found to increase with concomitant blue-shift with gradual addition of different surfactants. All the experimental results suggest that the probe molecule resides in the micelle-water interface rather than going into the micellar core. However, the penetration is more towards the micellar hydrocarbon core in nonionic surfactant (TX-100) while comparing with ionic surfactants (SDS and CTAB). Several mean microscopic properties such as critical micelle concentration, polarity parameters and binding constant were calculated in presence of different surfactants. The decrease in nonradiative decay rate constants in micellar environments indicates restricted motion of the probe inside the micellar nanocages with increasing fluorescence emission intensity and quantum yields. Further in this work, we also investigated the interaction behavior of the probe with different proteins at low concentrations under physiological conditions (pH = 7.4). Stern-Volmer analysis of the tryptophan (Trp) fluorescence quenching data in presence of probe reveals Stern-Volmer constant (Ksv) as well as bimolecular quenching rate constant (Kq). The binding constant as well as the number of binding sites of the probe with proteins were also monitored and found to be 1:1 stoichiometry ratio.
Publication
Journal: Journal of Inorganic Biochemistry
August/4/2019
Abstract
A series of eight hexacoordinated mixed-ligand oxidovanadium(IV) complexes [VO(Lx)(LN-N)] (1-8), where Lx = L1 - L4 are four differently substituted ONO donor aroylhydrazone ligands and LN-N are N,N-donor bases like 2,2'-bipyridine (bipy) (1, 3, 5 and 7) and 1,10-phenanthroline (phen) (2, 4, 6 and 8), have been reported. All synthesized complexes have been characterized by various physicochemical techniques and molecular structures of 1 and 6 were determined by X-ray crystallography. With a view to evaluate the biological activity of the VIVO species, the behavior of the systems VIVO2+/Lx, VIVO2+/Lx/bipy and VIVO2+/Lx/phen was studied as a function of pH in a mixture of H2O/DMSO 50/50 (v/v). DFT calculations allowed finding out the relative stability of the tautomeric forms of the ligands, and predicting the structure of vanadium complexes and their EPR parameters. To study their interaction with proteins, firstly the ternary systems VIVO2+/L1,2 with 1-methylimidazole, which is a good model for histidine binding, were examined. Subsequently the interaction of the complexes with lysozyme (Lyz), cytochrome c (Cyt) and bovine serum albumin (BSA) was studied. The results indicate that the complexes showed moderate binding affinity towards BSA, while no interaction takes place with lysozyme and cytochrome c. This could be explained with the higher number of accessible coordinating and polar residues for BSA than for Lyz and Cyt. Further, the complexes were also evaluated for their DNA binding propensity through UV-vis absorption titration and fluorescence spectral studies. These results were consistent with BSA binding affinity and showed moderate binding affinity towards CT-DNA.
Publication
Journal: Theriogenology
August/16/2018
Abstract
Antimicrobial peptides (AMP) are host defense peptides present in all species examined. The objective of the current study was to characterize the expression of a group of antimicrobial peptides in ovarian cells, and to investigate their expression response to pathogen ligands. It was found that while PG1 transcript was not detected in the ovary, the expression of BD2 is the highest in small follicle derived granulosa cells (SGC), and its expression decreases during follicular development to large follicle stage (LGC; p < 0.05). The expression of BD2 in cumulus cells also decreased from GV to MII stage of oocyte maturation. ANG4 expression increased in granulosa cells during follicular development from SGC to LGC stage (p < 0.05), although no significant difference was observed in cumulus cells from different stages of oocyte maturation. We further examined AMP expression in follicle cells treated with different toll-like receptor (TLR) ligands which mimic pathogen exposure in the ovary. Of the four TLR ligands examined, lipopolysaccharide (LPS) exposure resulted in a 11.5 fold increase of BD2 expression, and a significant decrease of LYZ in LGC. A similar response pattern in BD2 and LYZ expression was also observed in SGC. These responses of AMP expression to LPS are associated with increased TLR4 signaling pathway component in mRNA and protein level, such as MyD88 and NFkB, and pro-inflammatory cytokines/chemokines, such as IL-6, TNFα and IL-8 (p < 0.05). Our data suggest that AMPs may play a role in innate defense as well as other physiological functions during ovarian follicular development and oocyte maturation.
Related with
Publication
Journal: Physical Chemistry Chemical Physics
May/27/2021
Abstract
Colloidal protein-protein interactions (PPIs) of attractive and repulsive nature modulate the solubility of proteins, their aggregation, precipitation and crystallization. Such interactions are very important for many biotechnological processes, but are complex and hard to control, therefore, difficult to be understood in terms of measurements alone. In diluted protein solutions, PPIs can be estimated from the osmotic second virial coefficient, B22, which has been calculated using different methods and levels of theory. The most popular approach is based on the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and its extended versions, i.e. xDLVO. Despite much efforts, these models are not fully quantitative and must be fitted to experiments, which limits their predictive value. Here, we report an extended xDLVO-CG model, which extends existing models by a coarse-grained representation of proteins and the inclusion of an additional ion-protein dispersion interaction term. We demonstrate for four proteins, i.e. lysozyme (LYZ), subtilisin (Subs), bovine serum albumin (BSA) and immunoglobulin (IgG1), that semi-quantitative agreement with experimental values without the need to fit to experimental B22 values. While most likely not the final step in the nearly hundred years of research in PPIs, xDLVO-CG is a step towards predictive PPIs calculations that are transferable to different proteins.
Publication
Journal: DNA and Cell Biology
August/26/2020
Abstract
Sepsis is a life-threatening disorder and leads to organ dysfunction and death. Therefore, searching for more alternative biomarkers is of great significance for sepsis assessment and surveillance. In our study, the gene expression profiles of 163 samples from healthy controls and septic patients were analyzed and 8 gene co-expression modules were identified by constructing weighted gene co-expression network. The blue and yellow modules showed close correlations with the phenotypic trait "days postsepsis." Besides, differentially expressed genes (DEGs) over time in septic patients were screened using Short Time-series Expression Miner (STEM) program. The intersection of genes in the blue and yellow modules and DEGs, which were significantly enriched in "HTLV-1 infection" pathway, was analyzed with protein-protein interaction network. The logistic regression model based on these eight mRNAs was constructed to determine the type of the sample reliably. Eight vital genes CECR1, ANXA2, ELANE, CTSG, AZU1, PRTN3, LYZ, and DEFA4 presented high scores and may be associated with sepsis, which provided candidate biomarkers for sepsis.
Keywords: ANXA2; CECR1; ELANE; biomarker; sepsis; weighted gene co-expression network.
Publication
Journal: Paediatric nursing
July/7/1999
Abstract
Sometimes hospital is the best place for patients with cystic fibrosis, says Lyz Warren. Here she describes the choices available to children and parents on a unit which follows the philosophy adopted by The Children's Trust.
Authors
load more...