Effect of food additives on egg yolk gelation induced by freezing.

PubMed

Primacella, Monica; Fei, Tao; Acevedo, Nuria; Wang, Tong

2018-10-15

This study demonstrates technological advances in preventing yolk gelation during freezing and thawing. Gelation negatively affects yolk functionality in food formulation. Preventing gelation using 10% salt or sugar limits the application of the yolk. Novel food additives were tested to prevent gelation induced by freezing. Significant reduction (p < 0.05) in gel hardness of frozen-thawed yolk (45 h freezing at -20 °C) indicates that hydrolyzed carboxymethyl cellulose (HCMC), proline, and hydrolyzed egg white and yolk (HEW and HEY) are effective gelation inhibitors. The mechanisms in which these additives prevented gelation were further studied through measuring the changes in the amount of freezable water, lipoprotein particle size, and protein surface hydrophobicity. Overall, this study provides several alternatives of gelation inhibitor that have great potentials in replacing the use of salt or sugar in commercial operation of freezing egg yolk for shelf-life extension. Copyright © 2018 Elsevier Ltd. All rights reserved.

21 CFR 160.180 - Egg yolks.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Egg yolks. 160.180 Section 160.180 Food and Drugs... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.180 Egg yolks. (a) Egg yolks, liquid egg yolks, yolks, liquid yolks are yolks of eggs of the domestic hen so...

21 CFR 160.180 - Egg yolks.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Egg yolks. 160.180 Section 160.180 Food and Drugs... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.180 Egg yolks. (a) Egg yolks, liquid egg yolks, yolks, liquid yolks are yolks of eggs of the domestic hen so...

A mobile precursor determines protein resistance on nanostructured surfaces.

PubMed

Wang, Kang; Chen, Ye; Gong, Xiangjun; Xia, Jianlong; Zhao, Junpeng; Shen, Lei

2018-05-09

Biomaterials are often engineered with nanostructured surfaces to control interactions with proteins and thus regulate their biofunctions. However, the mechanism of how nanostructured surfaces resist or attract proteins together with the underlying design rules remains poorly understood at a molecular level, greatly limiting attempts to develop high-performance biomaterials and devices through the rational design of nanostructures. Here, we study the dynamics of nonspecific protein adsorption on block copolymer nanostructures of varying adhesive domain areas in a resistant matrix. Using surface plasmon resonance and single molecule tracking techniques, we show that weakly adsorbed proteins with two-dimensional diffusivity are critical precursors to protein resistance on nanostructured surfaces. The adhesive domain areas must be more than tens or hundreds of times those of the protein footprints to slow down the 2D-mobility of the precursor proteins for their irreversible adsorption. This precursor model can be used to quantitatively analyze the kinetics of nonspecific protein adsorption on nanostructured surfaces. Our method is applicable to precisely manipulate protein adsorption and resistance on various nanostructured surfaces, e.g., amphiphilic, low-surface-energy, and charged nanostructures, for the design of protein-compatible materials.

Antiproliferative Activity of Egg Yolk Peptides in Human Colon Cancer Cells.

PubMed

Yousr, Marwa N; Aloqbi, Akram A; Omar, Ulfat M; Howell, Nazlin K

2017-01-01

Egg yolk peptides were successfully prepared from egg yolk protein by-products after lecithin extraction. Defatted egg yolk protein was hydrolyzed with pepsin and pancreatin and purified by gel filtration to produce egg yolk gel filtration fraction (EYGF-33) with antiproliferative activity. The highlight of this study was that the peptide EYGF-33 (1.0 mg/ml) significantly inhibits cell viability of colon cancer cells (Caco-2) with no inhibitory effects on the viability of human colon epithelial normal cells (HCEC) after 48 h. Reduced cell viability can be explained by cell cycle arrest in the S-phase in which DNA replication normally takes place. EYGF-33 significantly enhanced the production of superoxide anions in the mitochondria of Caco-2 cells; this could activate a mitochondrial apoptotic pathway leading to typical Poly Adenosine diphosphate-ribose polymerase (PARP) cleavage as observed in the Western blot result. The induction of apoptotic cell death by EYGF-33 was supported by the externalization of phosphatidylserine (PS). However, further elucidation of the mechanism of EYGF-33-mediated apoptosis would provide further support for its use as a potential therapeutic and chemopreventive agent.

Amyloid precursor protein modulates macrophage phenotype and diet-dependent weight gain

PubMed Central

Puig, Kendra L.; Brose, Stephen A.; Zhou, Xudong; Sens, Mary A.; Combs, Gerald F.; Jensen, Michael D.; Golovko, Mikhail Y.; Combs, Colin K.

2017-01-01

It is well known that mutations in the gene coding for amyloid precursor protein are responsible for autosomal dominant forms of Alzheimer’s disease. Proteolytic processing of the protein leads to a number of metabolites including the amyloid beta peptide. Although brain amyloid precursor protein expression and amyloid beta production are associated with the pathophysiology of Alzheimer’s disease, it is clear that amyloid precursor protein is expressed in numerous cell types and tissues. Here we demonstrate that amyloid precursor protein is involved in regulating the phenotype of both adipocytes and peripheral macrophages and is required for high fat diet-dependent weight gain in mice. These data suggest that functions of this protein include modulation of the peripheral immune system and lipid metabolism. This biology may have relevance not only to the pathophysiology of Alzheimer’s disease but also diet-associated obesity. PMID:28262782

Increased KPI containing amyloid precursor protein in experimental autoimmune encephalomyelitis brains.

PubMed

Beilin, Orit; Karussis, Dimitrios M; Korczyn, Amos D; Gurwitz, David; Aronovich, Ramona; Mizrachi-Kol, Rachel; Chapman, Joab

2007-04-16

Amyloid precursor protein can be translated from three alternatively spliced mRNAs. We measured levels of amyloid precursor protein isoforms containing the Kunitz protease inhibitor domain (KPIAPP), and amyloid precursor protein without the Kunitz protease inhibitor domain (KPIAPP) in brain homogenates of acute experimental autoimmune encephalomyelitis mice. At the preclinical phase of the disease, both KPIAPP and KPIAPP levels were significantly higher in homogenates from brains of autoimmune encephalomyelitis mice, whereas at the acute phase of the disease only KPIAPP remained significantly elevated compared with controls. At the recovery phase, no differences were observed between the groups. The early and isoform-specific elevation of KPIAPP in autoimmune encephalomyelitis mice suggests a possible role for amyloid precursor protein in the immune response mediating the disease.

Nuclear localization of foamy virus Gag precursor protein.

PubMed Central

Schliephake, A W; Rethwilm, A

1994-01-01

All foamy viruses give rise to a strong nuclear staining when infected cells are reacted with sera from infected hosts. This nuclear fluorescence distinguishes foamy viruses from all other retroviruses. The experiments reported here indicate that the foamy virus Gag precursor protein is transiently located in the nuclei of infected cells and this is the likely reason for the typical foamy virus nuclear fluorescence. By using the vaccinia virus expression system, a conserved basic sequence motif in the nucleocapsid domain of foamy virus Gag proteins was identified to be responsible for the nuclear transport of the gag precursor molecule. This motif was also found to be able to direct a heterologous protein, the Gag protein of human immunodeficiency virus, into the nucleus. Images PMID:8035493

Mutational Analysis of the Rift Valley Fever Virus Glycoprotein Precursor Proteins for Gn Protein Expression

PubMed Central

Phoenix, Inaia; Lokugamage, Nandadeva; Nishiyama, Shoko; Ikegami, Tetsuro

2016-01-01

The Rift Valley fever virus (RVFV) M-segment encodes the 78 kD, NSm, Gn, and Gc proteins. The 1st AUG generates the 78 kD-Gc precursor, the 2nd AUG generates the NSm-Gn-Gc precursor, and the 3rd AUG makes the NSm’-Gn-Gc precursor. To understand biological changes due to abolishment of the precursors, we quantitatively measured Gn secretion using a reporter assay, in which a Gaussia luciferase (gLuc) protein is fused to the RVFV M-segment pre-Gn region. Using the reporter assay, the relative expression of Gn/gLuc fusion proteins was analyzed among various AUG mutants. The reporter assay showed efficient secretion of Gn/gLuc protein from the precursor made from the 2nd AUG, while the removal of the untranslated region upstream of the 2nd AUG (AUG2-M) increased the secretion of the Gn/gLuc protein. Subsequently, recombinant MP-12 strains encoding mutations in the pre-Gn region were rescued, and virological phenotypes were characterized. Recombinant MP-12 encoding the AUG2-M mutation replicated slightly less efficiently than the control, indicating that viral replication is further influenced by the biological processes occurring after Gn expression, rather than the Gn abundance. This study showed that, not only the abolishment of AUG, but also the truncation of viral UTR, affects the expression of Gn protein by the RVFV M-segment. PMID:27231931

Mutational Analysis of the Rift Valley Fever Virus Glycoprotein Precursor Proteins for Gn Protein Expression.

PubMed

Phoenix, Inaia; Lokugamage, Nandadeva; Nishiyama, Shoko; Ikegami, Tetsuro

2016-05-24

The Rift Valley fever virus (RVFV) M-segment encodes the 78 kD, NSm, Gn, and Gc proteins. The 1st AUG generates the 78 kD-Gc precursor, the 2nd AUG generates the NSm-Gn-Gc precursor, and the 3rd AUG makes the NSm'-Gn-Gc precursor. To understand biological changes due to abolishment of the precursors, we quantitatively measured Gn secretion using a reporter assay, in which a Gaussia luciferase (gLuc) protein is fused to the RVFV M-segment pre-Gn region. Using the reporter assay, the relative expression of Gn/gLuc fusion proteins was analyzed among various AUG mutants. The reporter assay showed efficient secretion of Gn/gLuc protein from the precursor made from the 2nd AUG, while the removal of the untranslated region upstream of the 2nd AUG (AUG2-M) increased the secretion of the Gn/gLuc protein. Subsequently, recombinant MP-12 strains encoding mutations in the pre-Gn region were rescued, and virological phenotypes were characterized. Recombinant MP-12 encoding the AUG2-M mutation replicated slightly less efficiently than the control, indicating that viral replication is further influenced by the biological processes occurring after Gn expression, rather than the Gn abundance. This study showed that, not only the abolishment of AUG, but also the truncation of viral UTR, affects the expression of Gn protein by the RVFV M-segment.

A novel isolation method for hen egg yolk antibody, "IgY".

PubMed

Hatta, H; Kim, M; Yamamoto, T

1990-10-01

A method for isolation of egg yolk immunoglobulin, IgG, a livetin protein, was investigated. Several natural gums (carrageenan and xanthan gum) were found to be effective for removal of yolk lipoprotein as a precipitate. The effect was pronounced with lambda-carrageenan and the lipid content in the supernatant after removal of the resulting precipitate was less than 0.4% of that of egg yolk. IgY remained in this supernatant, with a yield of 86%, and was isolated by chromatography on a column of DEAE-Sephacel followed by salting-out with sodium sulfate. IgY thus isolated was almost pure (98%) and the yield was 70 to 100 mg per egg.

Chloroplast precursor proteins compete to form early import intermediates in isolated pea chloroplasts.

PubMed

Row, P E; Gray, J C

2001-01-01

In order to ascertain whether there is one site for the import of precursor proteins into chloroplasts or whether different precursor proteins are imported via different import machineries, chloroplasts were incubated with large quantities of the precursor of the 33 kDa subunit of the oxygen-evolving complex (pOE33) or the precursor of the light-harvesting chlorophyll a/b-binding protein (pLHCP) and tested for their ability to import a wide range of other chloroplast precursor proteins. Both pOE33 and pLHCP competed for import into chloroplasts with precursors of the stromally-targeted small subunit of Rubisco (pSSu), ferredoxin NADP(+) reductase (pFNR) and porphobilinogen deaminase; the thylakoid membrane proteins LHCP and the Rieske iron-sulphur protein (pRieske protein); ferrochelatase and the gamma subunit of the ATP synthase (which are both associated with the thylakoid membrane); the thylakoid lumenal protein plastocyanin and the phosphate translocator, an integral membrane protein of the inner envelope. The concentrations of pOE33 or pLHCP required to cause half-maximal inhibition of import ranged between 0.2 and 4.9 microM. These results indicate that all of these proteins are imported into the chloroplast by a common import machinery. Incubation of chloroplasts with pOE33 inhibited the formation of early import intermediates of pSSu, pFNR and pRieske protein.

21 CFR 160.185 - Dried egg yolks.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Dried egg yolks. 160.185 Section 160.185 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.185 Dried egg yolks. (a) Dried egg yolks, dried yolks is the food prepared by drying egg yolks that conform to...

21 CFR 160.190 - Frozen egg yolks.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks that...

21 CFR 160.190 - Frozen egg yolks.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks that...

Yolk formation in some Charadriiform birds

USGS Publications Warehouse

Roudybush, T.E.; Grau, C.R.; Petersen, M.R.; Ainley, D.G.; Hirsch, K.V.; Gilman, A.P.; Patten, S.M.

1979-01-01

By counting and measuring the major ova of breeding birds at autopsy and combining these data with time intervals between ovipositions, rough estimates have been made of the time required to form yolk in some non-captive birds (King 1973). Direct studies have been made in domestic fowl (Gallus gallus var. domesticus; Gilbert 1972), turkeys (Meleagris galloparvo; Bacon and Cherms 1968), and Common quail (Coturnix coturnix; Bacon and Koontz 1971), by feeding the birds a capsule containing dye each day, and counting dye rings in the yolks after the eggs have been hardcooked. Recently developed methods of fixing and staining eggs have revealed differences in yolk deposited during day and night, thus permitting another estimation of the number of days during which yolk was deposited, and without direct contact with the female (Grau 1976). In eggs from chickens and quail that have been fed dyes, yolk that stained darkly with dichromate was shown to be deposited during the active daytime feeding periods, while pale-staining yolk was deposited during the night. Thus, pairs of light and dark rings, which together take a day to be deposited, may be counted to estimate time of yolk formation.In the present study we have applied the yolk ring method of estimating the number of days during which the bulk of the yolk is deposited around the central white core (Grau 1976) to the eggs of some shorebirds, gulls, terns and alcids.

Plasmodium vivax: a monoclonal antibody recognizes a circumsporozoite protein precursor on the sporozoite surface.

PubMed

Gonzalez-Ceron, L; Rodriguez, M H; Wirtz, R A; Sina, B J; Palomeque, O L; Nettel, J A; Tsutsumi, V

1998-11-01

The major surface circumsporozoite (CS) proteins are known to play a role in malaria sporozoite development and invasion of invertebrate and vertebrate host cells. Plasmodium vivax CS protein processing during mosquito midgut oocyst and salivary gland sporozoite development was studied using monoclonal antibodies which recognize different CS protein epitopes. Monoclonal antibodies which react with the CS amino acid repeat sequences by ELISA recognized a 50-kDa precursor protein in immature oocyst and additional 47- and 42-kDa proteins in older oocysts. A 42-kDa CS protein was detected after initial sporozoite invasion of mosquito salivary glands and an additional 50-kDa precursor CS protein observed later in infected salivary glands. These data confirm previous results with other Plasmodium species, in which more CS protein precursors were detected in oocysts than in salivary gland sporozoites. A monoclonal antibody (PvPCS) was characterized which reacts with an epitope found only in the 50-kDa precursor CS protein. PvPCS reacted with all P. vivax sporozoite strains tested by indirect immunofluorescent assay, homogeneously staining the sporozoite periphery with much lower intensity than that produced by anti-CS repeat antibodies. Immunoelectron microscopy using PvPCS showed that the CS protein precursor was associated with peripheral cytoplasmic vacuoles and membranes of sporoblast and budding sporozoites in development oocysts. In salivary gland sporozoites, the CS protein precursor was primarily associated with micronemes and sporozoite membranes. Our results suggest that the 50-kDa CS protein precursor is synthesized intracellularly and secreted on the membrane surface, where it is proteolytically processed to form the 42-kDa mature CS protein. These data indicate that differences in CS protein processing in oocyst and salivary gland sporozoites development may occur. Copyright 1998 Academic Press.

A novel chlorophyll a/b binding (Cab) protein gene from petunia which encodes the lower molecular weight Cab precursor protein.

PubMed

Stayton, M M; Black, M; Bedbrook, J; Dunsmuir, P

1986-12-22

The 16 petunia Cab genes which have been characterized are all closely related at the nucleotide sequence level and they encode Cab precursor polypeptides which are similar in sequence and length. Here we describe a novel petunia Cab gene which encodes a unique Cab precursor protein. This protein is a member of the smallest class of Cab precursor proteins for which no gene has previously been assigned in petunia or any other species. The features of this Cab precursor protein are that it is shorter by 2-3 amino acids than the formerly characterized Cab precursors, its transit peptide sequence is unrelated, and the mature polypeptide is significantly diverged at the functionally important N terminus from other petunia Cab proteins. Gene structure also discriminates this gene which is the only intron containing Cab gene in petunia genomic DNA.

Detection of rabies-specific antigens by egg yolk antibody (IgY) to the recombinant rabies virus proteins produced in Escherichia coli.

PubMed

Motoi, Yurie; Inoue, Satoshi; Hatta, Hajime; Sato, Kozue; Morimoto, Kinjiro; Yamada, Akio

2005-04-01

We obtained rabies-specific egg yolk antibodies (IgY) by immunizing hens with recombinant His-tagged nucleoprotein and phosphoprotein (rN, rP) of the rabies virus (CVS-11 strain) expressed in Escherichia coli. The anti-rN and rP IgY were shown to bind specifically to the respective proteins of the CVS-11 strain of rabies virus by Western blotting, immune fluorescent assay and immunohistochemistry, indicating that IgY to rabies recombinant proteins could serve as a reagent for diagnosis of rabies virus infection.

Using modified soy protein to enhance foaming of egg white protein.

PubMed

Wang, Guang; Troendle, Molly; Reitmeier, Cheryll A; Wang, Tong

2012-08-15

It is well known that the foaming properties of egg white protein are significantly reduced when a small amount of yolk is mixed in the white. To improve foaming properties of yolk-contaminated egg white protein, soy protein isolate (SPI) and egg proteins were modified to make basic proteins, and effects of these modified proteins on egg white foaming were evaluated in a model and an angel cake system. SPI and egg yolk proteins were modified to have an isoelectric point of 10, and sonication was used to increase protein dispersibility after the ethyl esterification reaction. However, only the addition of sonicated and modified SPI (SMSPI) showed improvement of foaming in the 5% egg protein model system with 0.4% yolk addition. SMSPI was then used in making angel food cake to examine whether the cake performance reduction due to yolk contamination of the white would be restored by such alkaline protein. Cake performance was improved when cream of tartar was used together with SMSPI. Basic soy protein can be made and used to improve egg white foaming properties and cake performance. Copyright © 2012 Society of Chemical Industry.

Porous yolk-shell microspheres as N-doped carbon matrix for motivating the oxygen reduction activity of oxygen evolution oriented materials.

PubMed

Zhou, Jinqiu; Wang, Mengfan; Qian, Tao; Liu, Sisi; Cao, Xuecheng; Yang, Tingzhou; Yang, Ruizhi; Yan, Chenglin

2017-09-08

It is highly challenging to explore high-performance bi-functional oxygen electrode catalysts for their practical application in next-generation energy storage and conversion devices. In this work, we synthesize hierarchical N-doped carbon microspheres with porous yolk-shell structure (NCYS) as a metal-free electrocatalyst toward efficient oxygen reduction through a template-free route. The enhanced oxygen reduction performances in both alkaline and acid media profit well from the porous yolk-shell structure as well as abundant nitrogen functional groups. Furthermore, such yolk-shell microspheres can be used as precursor materials to motivate the oxygen reduction activity of oxygen evolution oriented materials to obtain a desirable bi-functional electrocatalyst. To verify its practical utility, Zn-air battery tests are conducted and exhibit satisfactory performance, indicating that this constructed concept for preparation of bi-functional catalyst will afford a promising strategy for exploring novel metal-air battery electrocatalysts.

Porous yolk-shell microspheres as N-doped carbon matrix for motivating the oxygen reduction activity of oxygen evolution oriented materials

NASA Astrophysics Data System (ADS)

Zhou, Jinqiu; Wang, Mengfan; Qian, Tao; Liu, Sisi; Cao, Xuecheng; Yang, Tingzhou; Yang, Ruizhi; Yan, Chenglin

2017-09-01

It is highly challenging to explore high-performance bi-functional oxygen electrode catalysts for their practical application in next-generation energy storage and conversion devices. In this work, we synthesize hierarchical N-doped carbon microspheres with porous yolk-shell structure (NCYS) as a metal-free electrocatalyst toward efficient oxygen reduction through a template-free route. The enhanced oxygen reduction performances in both alkaline and acid media profit well from the porous yolk-shell structure as well as abundant nitrogen functional groups. Furthermore, such yolk-shell microspheres can be used as precursor materials to motivate the oxygen reduction activity of oxygen evolution oriented materials to obtain a desirable bi-functional electrocatalyst. To verify its practical utility, Zn-air battery tests are conducted and exhibit satisfactory performance, indicating that this constructed concept for preparation of bi-functional catalyst will afford a promising strategy for exploring novel metal-air battery electrocatalysts.

The multivariate egg: quantifying within- and among-clutch correlations between maternally derived yolk immunoglobulins and yolk androgens using multivariate mixed models.

PubMed

Postma, Erik; Siitari, Heli; Schwabl, Hubert; Richner, Heinz; Tschirren, Barbara

2014-03-01

Egg components are important mediators of prenatal maternal effects in birds and other oviparous species. Because different egg components can have opposite effects on offspring phenotype, selection is expected to favour their mutual adjustment, resulting in a significant covariation between egg components within and/or among clutches. Here we tested for such correlations between maternally derived yolk immunoglobulins and yolk androgens in great tit (Parus major) eggs using a multivariate mixed-model approach. We found no association between yolk immunoglobulins and yolk androgens within clutches, indicating that within clutches the two egg components are deposited independently. Across clutches, however, there was a significant negative relationship between yolk immunoglobulins and yolk androgens, suggesting that selection has co-adjusted their deposition. Furthermore, an experimental manipulation of ectoparasite load affected patterns of covariance among egg components. Yolk immunoglobulins are known to play an important role in nestling immune defence shortly after hatching, whereas yolk androgens, although having growth-enhancing effects under many environmental conditions, can be immunosuppressive. We therefore speculate that variation in the risk of parasitism may play an important role in shaping optimal egg composition and may lead to the observed pattern of yolk immunoglobulin and yolk androgen deposition across clutches. More generally, our case study exemplifies how multivariate mixed-model methodology presents a flexible tool to not only quantify, but also test patterns of (co)variation across different organisational levels and environments, allowing for powerful hypothesis testing in ecophysiology.

Yolk proteins in the male reproductive system of the fruit fly Drosophila melanogaster: spatial and temporal patterns of expression.

PubMed

Majewska, Magdalena M; Suszczynska, Agnieszka; Kotwica-Rolinska, Joanna; Czerwik, Tomasz; Paterczyk, Bohdan; Polanska, Marta A; Bernatowicz, Piotr; Bebas, Piotr

2014-04-01

In insects, spermatozoa develop in the testes as clones of single spermatogonia covered by specialized somatic cyst cells (cc). Upon completion of spermatogenesis, spermatozoa are released to the vas deferens, while the cc remain in the testes and die. In the fruit fly Drosophila melanogaster, the released spermatozoa first reach the seminal vesicles (SV), the organ where post-testicular maturation begins. Here, we demonstrate the temporal (restricted to the evening and early night hours) accumulation of membranous vesicles containing proteins in the SV lumen of D. melanogaster. When SV vesicles were isolated from the semen and co-incubated with testis-derived spermatozoa in vitro, their contents bound to the spermatozoa along their tails. The proteins of the SV vesicles were then characterized using 2-D electrophoresis. We identified a prominent protein spot of around 45-47 kDa, which disappears from the SV vesicles in the night, i.e. shortly after they appear in the SV lumen. Sequencing of peptides derived from this spot by mass spectrometry revealed identity with three yolk proteins (YP1-3). This unexpected result was confirmed by western blotting, which demonstrated that SV vesicles contain proteins that are immunoreactive with an antibody against D. melanogaster YP1-3. The expression of all yp genes was shown to be a unique feature of testis tissues. Using RNA probes we found that their transcripts localize exclusively to the cc that cover fully developed spermatozoa in the distal part of each testis. Temporally, the expression of yp genes was found to be restricted to a short period during the day and is followed by the evening accumulation of YP proteins in the cc. Immunohistochemical staining confirmed that cc are the source of SV vesicles containing YPs that are released into the SV lumen. These vesicles interact with spermatozoa and as a result, YPs become extrinsic proteins of the sperm membrane. Thus, we describe for the first time the expression of

Effect of Freezing, Thermal Pasteurization, and Hydrostatic Pressure on Fractionation and Folate Recovery in Egg Yolk.

PubMed

Naderi, Nassim; Pouliot, Yves; House, James D; Doyen, Alain

2017-09-06

In this study, the impact of pasteurization and freezing of raw material, as performed at a commercial scale, on egg yolk fractionation and folate recovery was assessed. Freezing induced denaturation of the lipoproteins in egg yolk, which prevented further fractionation of the yolk. Thermal pasteurization of egg yolk at 61.1 °C for 3.5 min as well as high hydrostatic pressure (HHP) treatment (400 MPa for 5 min) did not change (p < 0.05) the composition of egg yolk or yolk fractions after their recovery by centrifugation. Expressed as dry matter, folate in pasteurized yolk was measured to be 599 μg/100 g, while its concentration reached 1969.7 μg/100 g for pasteurized granule and 1902.5 μg/100 g for HHP-treated granule. Folate was not detected in plasma, emphasizing the complete separation of yolk folate into granule. Further, we studied the effect of HHP on different dilutions of egg yolk, which were then fractionated. Egg yolk was diluted with water at different concentrations (0.1, 1.0, 10, 25, and 50%), HHP-treated at 400 MPa for 5 min, and centrifuged. Characterization of the compositions of the separated granule and plasma followed. Folate was stable under the HHP conditions used. However, HHP caused separation of folate from the yolk structure into water-soluble plasma. After HHP processing, the amount of folate detected in the plasma fraction was significantly (p < 0.05) higher (1434.9 μg/100 g) in the 25% diluted samples but was significantly (p < 0.05) lower in HHP-treated granule samples. Native sodium dodecyl sulfate-polyacrylamide gel electrophoresis results showed that phosvitin, α-livetin, and apovitellenin VIa were the proteins most resistant to HHP. This study confirms that dilution of egg yolk before HHP treatment can significantly (p < 0.05) change the composition of granule and plasma fractions after centrifugal fractionation of egg yolk.

Generation of amyloid-β is reduced by the interaction of calreticulin with amyloid precursor protein, presenilin and nicastrin.

PubMed

Stemmer, Nina; Strekalova, Elena; Djogo, Nevena; Plöger, Frank; Loers, Gabriele; Lutz, David; Buck, Friedrich; Michalak, Marek; Schachner, Melitta; Kleene, Ralf

2013-01-01

Dysregulation of the proteolytic processing of amyloid precursor protein by γ-secretase and the ensuing generation of amyloid-β is associated with the pathogenesis of Alzheimer's disease. Thus, the identification of amyloid precursor protein binding proteins involved in regulating processing of amyloid precursor protein by the γ-secretase complex is essential for understanding the mechanisms underlying the molecular pathology of the disease. We identified calreticulin as novel amyloid precursor protein interaction partner that binds to the γ-secretase cleavage site within amyloid precursor protein and showed that this Ca(2+)- and N-glycan-independent interaction is mediated by amino acids 330-344 in the C-terminal C-domain of calreticulin. Co-immunoprecipitation confirmed that calreticulin is not only associated with amyloid precursor protein but also with the γ-secretase complex members presenilin and nicastrin. Calreticulin was detected at the cell surface by surface biotinylation of cells overexpressing amyloid precursor protein and was co-localized by immunostaining with amyloid precursor protein and presenilin at the cell surface of hippocampal neurons. The P-domain of calreticulin located between the N-terminal N-domain and the C-domain interacts with presenilin, the catalytic subunit of the γ-secretase complex. The P- and C-domains also interact with nicastrin, another functionally important subunit of this complex. Transfection of amyloid precursor protein overexpressing cells with full-length calreticulin leads to a decrease in amyloid-β42 levels in culture supernatants, while transfection with the P-domain increases amyloid-β40 levels. Similarly, application of the recombinant P- or C-domains and of a synthetic calreticulin peptide comprising amino acid 330-344 to amyloid precursor protein overexpressing cells result in elevated amyloid-β40 and amyloid-β42 levels, respectively. These findings indicate that the interaction of calreticulin with

Enteral Formula Containing Egg Yolk Lecithin Improves Diarrhea.

PubMed

Akashi, Tetsuro; Muto, Ayano; Takahashi, Yayoi; Nishiyama, Hiroshi

2017-09-01

Diarrhea often occurs during enteral nutrition. Recently, several reports showed that diarrhea improves by adding egg yolk lecithin, an emulsifier, in an enteral formula. Therefore, we evaluated if this combination could improve diarrhea outcomes. We retrospectively investigated the inhibitory effects on watery stools by replacing a polymeric fomula with that containing egg yolk lecithin. Then, we investigated the emulsion stability in vitro. Next, we examined the lipid absorption using different emulsifiers among bile duct-ligated rats and assessed whether egg yolk lecithin, medium-chain triglyceride, and dietary fiber can improve diarrhea outcomes in a rat model of short bowel syndrome. Stool consistency or frequency improved on the day after using the aforementioned combination in 13/14 patients. Average particle size of the egg yolk lecithin emulsifier did not change by adding artificial gastric juice, whereas that of soy lecithin and synthetic emulsifiers increased. Serum triglyceride concentrations were significantly higher in the egg yolk lecithin group compared with the soybean lecithin and synthetic emulsifier groups in bile duct-ligated rats. In rats with short bowels, the fecal consistency was a significant looser the dietary fiber (+) group than the egg yolk lecithin (+) groups from day 6 of test meal feedings. The fecal consistency was also a significant looser the egg yolk lecithin (-) group than the egg yolk lecithin (+) groups from day 4 of test meal feeding. The fecal consistency was no significant difference between the medium-chain triglycerides (-) and egg yolk lecithin (+) groups. Enteral formula emulsified with egg yolk lecithin promotes lipid absorption by preventing the destruction of emulsified substances by gastric acid. This enteral formula improved diarrhea and should reduce the burden on patients and healthcare workers.

Supplementation with tocotrienol-rich fraction alters the plasma levels of Apolipoprotein A-I precursor, Apolipoprotein E precursor, and C-reactive protein precursor from young and old individuals.

PubMed

Heng, Eng Chee; Karsani, Saiful Anuar; Abdul Rahman, Mariati; Abdul Hamid, Noor Aini; Hamid, Zalina; Wan Ngah, Wan Zurinah

2013-10-01

Tocotrienol possess beneficial effects not exhibited by tocopherol. In vitro studies using animal models have suggested that these effects are caused via modulation of gene and protein expression. However, human supplementation studies using tocotrienol-rich isomers are limited. This study aims to identify plasma proteins that changed in expression following tocotrienol-rich fraction (TRF) supplementation within two different age groups. Subjects were divided into two age groups-32 ± 2 (young) and 52 ± 2 (old) years old. Four subjects from each group were assigned with TRF (78% tocotrienol and 22% tocopherol, 150 mg/day) or placebo capsules for 6 months. Fasting plasma were obtained at 0, 3, and 6 months. Plasma tocopherol and tocotrienol levels were determined. Plasma proteome was resolved by 2DE, and differentially expressed proteins identified by MS. The expressions of three proteins were validated by Western blotting. Six months of TRF supplementation significantly increased plasma levels of tocopherols and tocotrienols. Proteins identified as being differentially expressed were related to cholesterol homeostasis, acute-phase response, protease inhibitor, and immune response. The expressions of Apolipoprotein A-I precursor, Apolipoprotein E precursor, and C-reactive protein precursor were validated. The old groups showed more proteins changing in expression. TRF appears to not only affect plasma levels of tocopherols and tocotrienols, but also the levels of plasma proteins. The identity of these proteins may provide insights into how TRF exerts its beneficial effects. They may also be potentially developed into biomarkers for the study of the effects and effectiveness of TRF supplementation.

Schisandrin B protects PC12 cells by decreasing the expression of amyloid precursor protein and vacuolar protein sorting 35★

PubMed Central

Yan, Mingmin; Mao, Shanping; Dong, Huimin; Liu, Baohui; Zhang, Qian; Pan, Gaofeng; Fu, Zhiping

2012-01-01

PC12 cell injury was induced using 20 μM amyloid β-protein 25–35 to establish a model of Alzheimer's disease. The cells were then treated with 5, 10, and 25 μM Schisandrin B. Methylthiazolyldiphenyl-tetrazolium bromide assays and Hoechst 33342 staining results showed that with increasing Schisandrin B concentration, the survival rate of PC12 cells injured by amyloid β-protein 25–35 gradually increased and the rate of apoptosis gradually decreased. Reverse transcription-PCR, immunocytochemical staining and western blot results showed that with increasing Schisandrin B concentration, the mRNA and protein expression of vacuolar protein sorting 35 and amyloid precursor protein were gradually decreased. Vacuolar protein sorting 35 and amyloid precursor protein showed a consistent trend for change. These findings suggest that 5, 10, and 25 μM Schisandrin B antagonizes the cellular injury induced by amyloid β-protein 25–35 in a dose-dependent manner. This may be caused by decreasing the expression of vacuolar protein sorting 35 and amyloid precursor protein. PMID:25745458

Homochiral Asymmetric Triacylglycerol Isomers in Egg Yolk.

PubMed

Nagai, Toshiharu; Ishikawa, Keiko; Yoshinaga, Kazuaki; Yoshida, Akihiko; Beppu, Fumiaki; Gotoh, Naohiro

2017-12-01

The composition of triacylglycerol (TAG) positional isomer (-PI) and enantiomer (-E) in immature chicken egg yolk, mature chicken yolk, and chicken meat was examined. POO (consisting of one palmitic acid (P) and two oleic acids (Os)), PPO (consisting of two Ps and one O), and PPL (consisting of two Ps and one linoleic acid (L)) were treated as representative TAG molecular species in all the analytical samples because P, O, and L were the major fatty acids comprising egg and chicken meat. sn-POO (binding P at sn-1 position) was predominant in egg yolks, while sn-OOP and sn-OPO were present in chicken meat. This difference was ascribed to the different roles of these isomers as nutrients, because TAG in egg yolk is important for new born organisms and TAG in chicken meat is used for fat accumulation. The compositions of the TAG isomers in PPO and PPL in egg yolk were similar, and O and L did not bind at the sn-1 position. In contrast, all the isomers of PPO and PPL were found in chicken meat. These results imply that the TAG structure could be modified so that the nutrient requirement is fulfilled in egg yolk and chicken meat.

Food safety effects of unabsorbed yolks in broilers

USDA-ARS?s Scientific Manuscript database

In the developing avian embryo, the main energy source is the yolk. Toward the end of the incubation period, the remaining yolk sac is internalized into the abdominal cavity. At hatch, the remaining yolk comprises 20% of the chick’s body weight and provides the nutrients needed for maintenance. P...

Effects of lipid extraction on stable isotope ratios in avian egg yolk: Is arithmetic correction a reliable alternative?

USGS Publications Warehouse

Oppel, S.; Federer, R.N.; O'Brien, D. M.; Powell, A.N.; Hollmén, Tuula E.

2010-01-01

Many studies of nutrient allocation to egg production in birds use stable isotope ratios of egg yolk to identify the origin of nutrients. Dry egg yolk contains >50% lipids, which are known to be depleted in 13C. Currently, researchers remove lipids from egg yolk using a chemical lipid-extraction procedure before analyzing the isotopic composition of protein in egg yolk. We examined the effects of chemical lipid extraction on ??13C, ??15N, and ??34S of avian egg yolk and explored the utility of an arithmetic lipid correction model to adjust whole yolk ??13C for lipid content. We analyzed the dried yolk of 15 captive Spectacled Eider (Somateriafischeri) and 20 wild King Eider (S. spectabilis) eggs, both as whole yolk and after lipid extraction with a 2:1 chloroform:methanol solution. We found that chemical lipid extraction leads to an increase of (mean ?? SD) 3.3 ?? 1.1% in ??13C, 1.1 ?? 0.5% in ??15N, and 2.3 ?? 1.1% in ??34S. Arithmetic lipid correction provided accurate values for lipid-extracted S13C in captive Spectacled Eiders fed on a homogeneous high-quality diet. However, arithmetic lipid correction was unreliable for wild King Eiders, likely because of their differential incorporation of macronutrients from isotopically distinct environments during migration. For that reason, we caution against applying arithmetic lipid correction to the whole yolk ??13C of migratory birds, because these methods assume that all egg macronutrients are derived from the same dietary sources. ?? 2010 The American Ornithologists' Union.

Redundancy and divergence in the amyloid precursor protein family.

PubMed

Shariati, S Ali M; De Strooper, Bart

2013-06-27

Gene duplication provides genetic material required for functional diversification. An interesting example is the amyloid precursor protein (APP) protein family. The APP gene family has experienced both expansion and contraction during evolution. The three mammalian members have been studied quite extensively in combined knock out models. The underlying assumption is that APP, amyloid precursor like protein 1 and 2 (APLP1, APLP2) are functionally redundant. This assumption is primarily supported by the similarities in biochemical processing of APP and APLPs and on the fact that the different APP genes appear to genetically interact at the level of the phenotype in combined knockout mice. However, unique features in each member of the APP family possibly contribute to specification of their function. In the current review, we discuss the evolution and the biology of the APP protein family with special attention to the distinct properties of each homologue. We propose that the functions of APP, APLP1 and APLP2 have diverged after duplication to contribute distinctly to different neuronal events. Our analysis reveals that APLP2 is significantly diverged from APP and APLP1. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Sequestration of PDC-109 protein by specific antibodies and egg yolk cryoprotects bull spermatozoa.

PubMed

Srivastava, N; Srivastava, S K; Ghosh, S K; Jerome, A; Das, G K; Mehrotra, S

2013-10-01

PDC-109, one of the most abundant proteins in bovine seminal plasma, has detrimental effect on spermatozoa in a time- and concentration-dependent manner. Therefore, we hypothesized that sequestration of detrimental protein from ejaculates would be beneficial following cryopreservation of sperm cells. To this aim, we evaluated the effect of sequestration of PDC-109 either by anti-PDC-109 antibodies (Ab) or egg yolk (EY) alone or by the synergistic action of EY + Ab in minimizing cryoinjury to bull spermatozoa. PDC-109 protein was purified by applying two-step chromatography procedures. The purified protein was injected in rabbits to raise antibodies which were isolated using ion-exchange chromatography. After checking the Ab cross-reactivity, they were quantitated and added to ejaculates, either alone or in addition to EY in Tris-glycerol (TG) extender. Thus, ejaculates were processed in extender containing EY + TG (group I), Ab + TG (group II) or EY + Ab + TG (group III). Semen quality parameters (SQPs) viz. viability and acrosome integrity (FITC-PSA), cryoinjury to spermatozoa (chlortetracycline, CTC assay) and in vitro fertility of protein-sequestered-semen (zona-penetration assay) were evaluated. A significant (p < 0.05) improvement in post-thaw SQPs as well as in non-capacitated spermatozoa observed at pre-freeze and post-thaw stages of cryopreservation in group III compared with other groups indicated reduction in protein-mediated cryoinjury. From this study, it can be concluded that sequestration of PDC-109 by synergistic action of EY+Ab as compared to either of them alone significantly improve sperm quality and minimize cryoinjury to bull spermatozoa upon storage at ultra-low temperatures. © 2013 Blackwell Verlag GmbH.

Gc protein (vitamin D-binding protein): Gc genotyping and GcMAF precursor activity.

PubMed

Nagasawa, Hideko; Uto, Yoshihiro; Sasaki, Hideyuki; Okamura, Natsuko; Murakami, Aya; Kubo, Shinichi; Kirk, Kenneth L; Hori, Hitoshi

2005-01-01

The Gc protein (human group-specific component (Gc), a vitamin D-binding protein or Gc globulin), has important physiological functions that include involvement in vitamin D transport and storage, scavenging of extracellular G-actin, enhancement of the chemotactic activity of C5a for neutrophils in inflammation and macrophage activation (mediated by a GalNAc-modified Gc protein (GcMAF)). In this review, the structure and function of the Gc protein is focused on especially with regard to Gc genotyping and GcMAF precursor activity. A discussion of the research strategy "GcMAF as a target for drug discovery" is included, based on our own research.

Ovarian mixed germ cell tumor with yolk sac and teratomatous components in a dog.

PubMed

Robinson, Nicholas A; Manivel, J Carlos; Olson, Erik J

2013-05-01

Mixed germ cell tumors of the ovary have rarely been reported in veterinary species. A 3-year-old intact female Labrador Retriever dog was presented for lethargy, abdominal distention, and a midabdominal mass. An exploratory laparotomy revealed a large (23 cm in diameter) left ovarian tumor and multiple small (2-3 cm in diameter) pale tan masses on the peritoneum and abdominal surface of the diaphragm. Histological examination of the left ovary revealed a mixed germ cell tumor with a yolk sac component with rare Schiller-Duval bodies and a teratomatous component comprised primarily of neural differentiation. The abdominal metastases were solely comprised of the yolk sac component. The yolk sac component was diffusely immunopositive for cytokeratin with scattered cells reactive for α-fetoprotein and placental alkaline phosphatase. Within the teratomatous component, the neuropil was diffusely immunopositive for S100, neuron-specific enolase, and neurofilaments with a few glial fibrillary acidic protein immunopositive cells. Ovarian germ cell tumors may be pure and consist of only 1 germ cell element or may be mixed and include more than 1 germ cell element, such as teratoma and yolk sac tumor.

Association of the macrophage activating factor (MAF) precursor activity with polymorphism in vitamin D-binding protein.

PubMed

Nagasawa, Hideko; Sasaki, Hideyuki; Uto, Yoshihiro; Kubo, Shinichi; Hori, Hitoshi

2004-01-01

Serum vitamin D-binding protein (Gc protein or DBP) is a highly expressed polymorphic protein, which is a precursor of the inflammation-primed macrophage activating factor, GcMAF, by a cascade of carbohydrate processing reactions. In order to elucidate the relationship between Gc polymorphism and GcMAF precursor activity, we estimated the phagocytic ability of three homotypes of Gc protein, Gc1F-1F, Gc1S-1S and Gc2-2, through processing of their carbohydrate moiety. We performed Gc typing of human serum samples by isoelectric focusing (IEF). Gc protein from human serum was purified by affinity chromatography with 25-hydroxyvitamin D3-sepharose. A phagocytosis assay of Gc proteins, modified using beta-glycosidase and sialidase, was carried out. The Gc1F-1F phenotype was revealed to possess Galbeta1-4GalNAc linkage by the analysis of GcMAF precursor activity using beta1-4 linkage-specific galactosidase from jack bean. The GcMAF precursor activity of the Gc1F-1F phenotype was highest among three Gc homotypes. The Gc polymorphism and carbohydrate diversity of Gc protein are significant for its pleiotropic effects.

Dynamics of a suspension of interacting yolk-shell particles

DOE PAGES

Sánchez Díaz, L. E.; Cortes-Morales, E. C.; Li, X.; ...

2014-12-01

In this work we study the self-diusion properties of a liquid of hollow spherical particles (shells) bearing a smaller solid sphere in their interior (yolks). We model this system using purely repulsive hard-body interactions between all (shell and yolk) particles, but assume the presence of a background ideal solvent such that all the particles execute free Brownian motion between collisions, characterized by short-time self-diusion coecients D0 s for the shells and D0 y for the yolks. Using a softened version of these interparticle potentials we perform Brownian dynamics simulations to determine the mean squared displacement and intermediate scattering function ofmore » the yolk-shell complex. These results can be understood in terms of a set of eective Langevin equations for the N interacting shell particles, pre-averaged over the yolks' degrees of freedom, from which an approximate self-consistent description of the simulated self-diusion properties can be derived. Here we compare the theoretical and simulated results between them, and with the results for the same system in the absence of yolks. We nd that the yolks, which have no eect on the shell-shell static structure, in uence the dynamic properties in a predictable manner, fully captured by the theory.« less

Oil exudation and histological structures of duck egg yolks during brining.

PubMed

Lai, K M; Chung, W H; Jao, C L; Hsu, K C

2010-04-01

Changes in oil exudation and histological structures of salted duck egg yolks during brining up to 5 wk were investigated. During brining, the salt contents of albumen, exterior yolk (hardened portion), and interior yolk (soft or liquid portion) gradually increased accompanied by slight decreases in moisture content. The hardening ratio of salted egg yolks increased rapidly to about 60% during the first week of brining and then reached 100% at the end of brining. After brining, part of the lipids in salted egg yolk became free due to the structural changes of low-density lipoprotein induced by dehydration and increase of salt content, and more free lipids in salted egg yolk were released after the cooking process. With the brining time increased up to 5 wk, the outer region of the cooked salted yolk gradually changed into dark brown, brown, orange, and then dark brown, whereas the center region changed into light yellow, yellow, dark yellow, and then yellow again. The microstructures of cooked salted egg yolks showed that the yolk spheres in the outer and middle regions retained their original shape, with some shrinking and being packed more loosely when brining time increased, and the exuded oil filled the space between the spheres. Furthermore, the yolk spheres in the center region transformed to a round shape but still showed granulation after 4 wk of brining, whereas they were mostly disrupted after 2 to 5 wk of brining. One of the most important characteristics of cooked salted egg yolks, gritty texture, contributed to oil exudation and granulated yolk spheres were observed at the brining time of 4 wk.

Laser-induced transformation of supramolecular complexes: approach to controlled formation of hybrid multi-yolk-shell Au-Ag@a-C:H nanostructures

PubMed Central

Manshina, A. A.; Grachova, E. V.; Povolotskiy, A. V.; Povolotckaia, A. V.; Petrov, Y. V.; Koshevoy, I. O.; Makarova, A. A.; Vyalikh, D. V.; Tunik, S. P.

2015-01-01

In the present work an efficient approach of the controlled formation of hybrid Au–Ag–C nanostructures based on laser-induced transformation of organometallic supramolecular cluster compound is suggested. Herein the one-step process of the laser-induced synthesis of hybrid multi-yolk-shell Au-Ag@a-C:H nanoparticles which are bimetallic gold-silver subnanoclusters dispersed in nanospheres of amorphous hydrogenated a-C:H carbon is reported in details. It has been demonstrated that variation of the experimental parameters such as type of the organometallic precursor, solvent, deposition geometry and duration of laser irradiation allows directed control of nanoparticles’ dimension and morphology. The mechanism of Au-Ag@a-C:H nanoparticles formation is suggested: the photo-excitation of the precursor molecule through metal-to-ligand charge transfer followed by rupture of metallophilic bonds, transformation of the cluster core including red-ox intramolecular reaction and aggregation of heterometallic species that results in the hybrid metal/carbon nanoparticles with multi-yolk-shell architecture formation. It has been found that the nanoparticles obtained can be efficiently used for the Surface-Enhanced Raman Spectroscopy label-free detection of human serum albumin in low concentration solution. PMID:26153347

Using life-histories to predict and interpret variability in yolk hormones.

PubMed

Love, O P; Gilchrist, H G; Bêty, J; Wynne-Edwards, K E; Berzins, L; Williams, T D

2009-09-01

Variation in yolk hormones is assumed to provide the plasticity necessary for mothers to individually optimize reproductive decisions via changes in offspring phenotype, the benefit being to maximise fitness. However, rather than routinely expecting adaptive variation within all species, the pattern and magnitude of yolk hormone deposition should theoretically relate to variation in life-histories. Here we present data on intra-clutch variation in yolk corticosterone in three species along a developmental continuum (European starling (Sturnus vulgaris): fully altricial; black guillemot (Cepphus grylle): semi-precocial; common eider (Somateria mollissima): fully precocial) to examine how and why variation in life-histories might relate to the evolution of variation in yolk steroids. Starlings and guillemots showed a significant increase in yolk corticosterone across the laying sequence; however, we found no pattern within eider clutches. Moreover, starlings showed the largest difference (94.6%) in yolk corticosterone between first- and last-laid eggs, whereas guillemots showed a moderate difference (58.9%). Despite these general species-specific patterns, individuals showed marked variation in the intra-clutch patterns of yolk corticosterone within each species indicating potential differences in intra-clutch flexibility among females. It is well documented that exposure to elevated yolk glucocorticoids reduces offspring quality at birth/hatching in many taxa and it has therefore been proposed that elevated yolk levels may modulate offspring competition and/or facilitate brood reduction under harsh conditions in birds. Our data suggests that intra-clutch variation in yolk corticosterone has the potential to act as an adaptive maternal effect in species where modulation of competition between nest-bound offspring would benefit mothers (starlings and guillemots). However, in precocial species where mothers would not benefit from a modulation of offspring quality

Increased neuronal beta-amyloid precursor protein expression in human temporal lobe epilepsy: association with interleukin-1 alpha immunoreactivity.

PubMed

Sheng, J G; Boop, F A; Mrak, R E; Griffin, W S

1994-11-01

Levels of immunoreactive beta-amyloid precursor protein and interleukin-1 alpha were found to be elevated in surgically resected human temporal lobe tissue from patients with intractable epilepsy compared with postmortem tissue from neurologically unaffected patients (controls). In tissue from epileptics, the levels of the 135-kDa beta-amyloid precursor protein isoform were elevated to fourfold (p < 0.05) those of controls and those of the 130-kDa isoform to threefold (p < 0.05), whereas those of the 120-kDa isoform (p > 0.05) were not different from control values. beta-Amyloid precursor protein-immunoreactive neurons were 16 times more numerous, and their cytoplasm and proximal processes were more intensely immunoreactive in tissue sections from epileptics than controls (133 +/- 12 vs. 8 +/- 3/mm2; p < 0.001). However, neither beta-amyloid precursor protein-immunoreactive dystrophic neurites nor beta-amyloid deposits were found in this tissue. Interleukin-1 alpha-immunoreactive cells (microglia) were three times more numerous in epileptics than in controls (80 +/- 8 vs. 25 +/- 5/mm2; p < 0.001), and these cells were often found adjacent to beta-amyloid precursor protein-immunoreactive neuronal cell bodies. Our findings, together with functions established in vitro for interleukin-1, suggest that increased expression of this protein contributes to the increased levels of beta-amyloid precursor protein in epileptics, thus indicating a potential role for both of these proteins in the neuronal dysfunctions, e.g., hyperexcitability, characteristic of epilepsy.

Soft template synthesis of yolk/silica shell particles.

PubMed

Wu, Xue-Jun; Xu, Dongsheng

2010-04-06

Yolk/shell particles possess a unique structure that is composed of hollow shells that encapsulate other particles but with an interstitial space between them. These structures are different from core/shell particles in that the core particles are freely movable in the shell. Yolk/shell particles combine the properties of each component, and can find potential applications in catalysis, lithium ion batteries, and biosensors. In this Research News article, a soft-template-assisted method for the preparation of yolk/silica shell particles is presented. The demonstrated method is simple and general, and can produce hollow silica spheres incorporated with different particles independent of their diameters, geometry, and composition. Furthermore, yolk/mesoporous silica shell particles and multishelled particles are also prepared through optimization of the experimental conditions. Finally, potential applications of these particles are discussed.

Effects of yolk contamination, shearing, and heating on foaming properties of fresh egg white.

PubMed

Wang, G; Wang, T

2009-03-01

A series of experiments were conducted to evaluate effects of yolk contamination, shearing, and thermal treatment on foaming properties of liquid egg white. Samples obtained from industrial processing were also evaluated. Whipping and purging methods were both used to assess their effectiveness and sensitivity in evaluating foaming. A concentration as low as 0.022% (as-is basis) of yolk contamination caused significant reductions in foaming capacity and foaming speed. The neutral lipid fraction of egg yolk caused the major detrimental effect on foaming, and phospholipids fraction did not give significant foaming reduction at a concentration as high as 0.1%. High-speed and short-time shearing caused no apparent damage but longer shearing time significantly impaired foaming. Heat-induced foaming change is a function of temperature and holding time. Foaming was significantly reduced at a temperature of 55 degrees C for 10 min, whereas it did not change up to 3 min at a heating temperature of 62 to 64 degrees C. Industrial processing steps (pumping, pipe transfer, and storage) did not produce negative effects on foaming of the final products and the controlled pasteurization was actually beneficial for good foaming performance. Therefore, yolk contamination of the egg white was the major factor in reducing foaming properties of the white protein.

Effect of dietary manipulation and vaccination of turkey breeder hens on immunoglobulin levels of yolk, yolk sac and neonate poults.

PubMed

Bhattacharyya, A; Majumdar, S; Bhanja, S K; Mandal, A B; Dash, B B

2018-04-01

Two hundred turkey breeder hens and 24 viable toms of 30-35 weeks age of small white variety were distributed into two treatment groups having four replicates of 25 hens and three toms in each treatment. First four replicates were offered a turkey breeder diet (Diet A) (Nutrient requirements of poultry, 1994, National Academic Press, Washington, DC) and the rest four replicates were maintained on a higher plane of nutrition (Diet B) for 8-week duration. After 6 weeks of experimental feeding, two replicates from each treatment groups were vaccinated with ND (R 2 B) vaccine. Yolk sac of embryo from birds fed Diet B had a significantly higher (p < .05) IgG, IgM level and HI titre (log 2) than those fed Diet A. HI titre values of embryonic yolk sac from the vaccinated birds fed Diet B were significantly higher (p < .05) than that of the control groups. In addition, HI titre values were significantly higher (p < .05) in the day-old poults of the birds fed Diet B than that of those fed Diet A. There was significantly (p < .01) positive correlation between serum IgG and IgM of the breeder birds and day-old chicks. Similarly, there was significantly (p < .05) positive correlation between yolk IgG and IgM after 1-month experimental feeding and yolk sac IgG and IgM. Positive correlation (p < .05) also existed between yolk sac IgM and day-old chick serum IgM. Furthermore, the HI titres of breeder birds' serum at 14 days post-vaccination were positively correlated with their egg yolk after 10 and 15 days post-vaccination, yolk sac and day-old chicks. Thus, the study envisaged that a higher immunity in neonate poults from turkey breeders maintained on a higher plane of nutrition may be elicited as there was maternal transfer of antibodies from the serum of breeder birds to their offsprings through their yolk sac. © 2018 Blackwell Verlag GmbH.

Changes of Protein and Lipid Contents, Amino Acid and Fatty Acid Compositions in Eggs and Yolk-Sac Larvae of American Shad ( Alosa sapidissima)

NASA Astrophysics Data System (ADS)

Liu, Zhifeng; Gao, Xiaoqiang; Yu, Jiuxiang; Wang, Yaohui; Guo, Zhenglong; Huang, Bin; Liu, Baoliang; Hong, Lei

2018-04-01

To investigate the changes of the biochemical composition of American shad ( Alosa sapidissima) eggs and larvae at embryonic and early larval stages, samples were collected at different development stages from artificial fertilization to the end of yolk absorption including 2 h, 12 h and 30 h after fertilization and newly hatched larvae including 1 and 3 days after hatching. The composition of lipid, fatty acids, protein and amino acids were analyzed. The content of total protein exhibited a decreasing trend during embryogenesis and larval development, and a significant reduction was detected after hatching ( P < 0.05). The total lipid content remained relative stable. A significant reduction was detected in almost all amino acids after hatching except for glycine ( P < 0.05), while a significant decrease was found in the content of cysteine, proline, tyrosine, valine, isoleucine, leucine and phenylalanine during the yolk-sac phase ( P < 0.05). On the other hand, all the groups of fatty acids remained stable during the period of embryogenesis. But after hatching, a significant decrease was found in the content of C18:2n-6, C18:3n-6, SFA and ratio of EPA/ARA ( P < 0.05), while a significant increase was found in the content of C18:3n-3, C20:4n-6, C22:6n-3 and ratio of n-3/n-6 ( P < 0.05). In conclusion, the combined data suggested that American shad utilizes the protein content as preferential energy substrates during embryonic and early larval developments with some specificity in the consumption of different amino acids.

Protection of rats against dental caries by passive immunization with hen-egg-yolk antibody (IgY).

PubMed

Otake, S; Nishihara, Y; Makimura, M; Hatta, H; Kim, M; Yamamoto, T; Hirasawa, M

1991-03-01

Hen-egg-yolk antibody (IgY) was prepared against Streptococcus mutans MT8148 serotype c that was cultivated in medium containing sucrose, and it was used in passive caries-immunity studies. Specific pathogen-free rats infected with S. mutans MT8148 (c) and fed with a cariogenic diet containing more than 2% immune yolk powder developed significantly lower caries scores than did the ones infected with the same strain and fed with a diet containing only control yolk powder obtained from non-immunized hens. Similar results were obtained in an experiment with rats infected with S. mutans JC-2 (c) strain. Rats provided a diet supplemented with 0.5% immune water-soluble protein fraction containing S. mutans-specific IgY and challenged with S. mutans MT8148 exhibited significantly fewer caries lesions, compared with control rats on the normal diet.

Effect of domestic cooking methods on egg yolk xanthophylls.

PubMed

Nimalaratne, Chamila; Lopes-Lutz, Daise; Schieber, Andreas; Wu, Jianping

2012-12-26

Xanthophylls are a class of bioactive compounds known to play an important role in preventing age-related macular degeneration. Egg yolk is a rich source of highly bioavailable xanthophylls including lutein and zeaxanthin. The effects of domestic cooking methods (boiling, frying, microwaving) on egg yolk xanthophyll content were investigated. A LC-(APCI)-MS/MS method was used to identify and quantify all-E- and Z-isomers of lutein, zeaxanthin, canthaxanthin, and β-apo-8'-carotenoic acid ethyl ester in fresh and cooked egg yolks. Both fresh and cooked yolks showed similar xanthophyll profiles but with higher contents of Z-isomers in cooked samples. All-E-lutein was the most affected, with 22.5%, 16.7%, and 19.3% reductions in boiled, microwaved, and fried yolk extracts, respectively. Total xanthophyll losses ranged from 6% to 18%. The results presented here could be useful in calculating the dietary intake of xanthophylls and also in assessing the xanthophyll profiles and contents of egg-containing products.

The potency of chicken egg yolk immunoglobulin (IgY) specific as immunotherapy to Mycobacterium tuberculosis infection

PubMed Central

Sudjarwo, Sri Agus; Eraiko, Koerniasari; Sudjarwo, Giftania Wardani; Koerniasari

2017-01-01

The aim of this study was to characterize of chicken egg yolk immunoglobulins (IgYs) specific as immunotherapy to Mycobacterium tuberculosis complex (MTBC) infection. Lohmann laying hens were immunized intramuscularly with antigenic of MTBC. Egg yolk was separated from egg white, and IgY antibody was then purified by multiple polyethylene glycols 6000 extraction and ammonium sulfate purification steps. The IgY anti-MTBC concentration in egg yolk increased at 2 weeks and it reached a maximum at 4 weeks after immunization. After 6 weeks, the levels of IgY anti-MTBC decreased gradually. The antibody of MTBC was detected and produces a specific line of precipitation in agar gel precipitation test beginning the week 2 after the first immunization. Analysis of results obtained with ELISA showed a significant increase in the MTBC specific antibodies after 2 weeks and reached a plateau at 4 weeks from the booster immunization. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the IgY preparation to be pure and dissociated into protein bands with molecular weights of 112, 78, 69, 49, and 28 kDa and Western blot analysis shown the presence of anti-MTBC IgY in egg yolks, with molecular weights of approximately 78 kDa. These results suggested that egg yolk could be a practical strategy in large-scale production of specific anti-MTBC IgY for immunotherapy of TBC. PMID:28795022

The potency of chicken egg yolk immunoglobulin (IgY) specific as immunotherapy to Mycobacterium tuberculosis infection.

PubMed

Sudjarwo, Sri Agus; Eraiko, Koerniasari; Sudjarwo, Giftania Wardani; Koerniasari

2017-01-01

The aim of this study was to characterize of chicken egg yolk immunoglobulins (IgYs) specific as immunotherapy to Mycobacterium tuberculosis complex (MTBC) infection. Lohmann laying hens were immunized intramuscularly with antigenic of MTBC. Egg yolk was separated from egg white, and IgY antibody was then purified by multiple polyethylene glycols 6000 extraction and ammonium sulfate purification steps. The IgY anti-MTBC concentration in egg yolk increased at 2 weeks and it reached a maximum at 4 weeks after immunization. After 6 weeks, the levels of IgY anti-MTBC decreased gradually. The antibody of MTBC was detected and produces a specific line of precipitation in agar gel precipitation test beginning the week 2 after the first immunization. Analysis of results obtained with ELISA showed a significant increase in the MTBC specific antibodies after 2 weeks and reached a plateau at 4 weeks from the booster immunization. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the IgY preparation to be pure and dissociated into protein bands with molecular weights of 112, 78, 69, 49, and 28 kDa and Western blot analysis shown the presence of anti-MTBC IgY in egg yolks, with molecular weights of approximately 78 kDa. These results suggested that egg yolk could be a practical strategy in large-scale production of specific anti-MTBC IgY for immunotherapy of TBC.

Yolk sac development in lizards (Lacertilia: Scincidae): New perspectives on the egg of amniotes.

PubMed

Stewart, James R; Thompson, Michael B

2017-04-01

Embryos of oviparous reptiles develop on the surface of a large mass of yolk, which they metabolize to become relatively large hatchlings. Access to the yolk is provided by tissues growing outward from the embryo to cover the surface of the yolk. A key feature of yolk sac development is a dedicated blood vascular system to communicate with the embryo. The best known model for yolk sac development and function of oviparous amniotes is based on numerous studies of birds, primarily domestic chickens. In this model, the vascular yolk sac forms the perimeter of the large yolk mass and is lined by a specialized epithelium, which takes up, processes and transports yolk nutrients to the yolk sac blood vessels. Studies of lizard yolk sac development, dating to more than 100 years ago, report characteristics inconsistent with this model. We compared development of the yolk sac from oviposition to near hatching in embryonic series of three species of oviparous scincid lizards to consider congruence with the pattern described for birds. Our findings reinforce results of prior studies indicating that squamate reptiles mobilize and metabolize the large yolk reserves in their eggs through a process unknown in other amniotes. Development of the yolk sac of lizards differs from birds in four primary characteristics, migration of mesoderm, proliferation of endoderm, vascular development and cellular diversity within the yolk sac cavity. Notably, all of the yolk is incorporated into cells relatively early in development and endodermal cells within the yolk sac cavity align along blood vessels which course throughout the yolk sac cavity. The pattern of uptake of yolk by endodermal cells indicates that the mechanism of yolk metabolism differs between lizards and birds and that the evolution of a fundamental characteristic of embryonic nutrition diverged in these two lineages. Attributes of the yolk sac of squamates reveal the existence of phylogenetic diversity among amniote lineages

Study on aggregation behavior of low density lipoprotein in hen egg yolk plasma by asymmetrical flow field-flow fractionation coupled with multiple detectors.

PubMed

Dou, Haiyang; Magnusson, Emma; Choi, Jaeyeong; Duan, Fei; Nilsson, Lars; Lee, Seungho

2016-02-01

In this study, asymmetrical flow field-flow fractionation (AF4) coupled online with UV, multiangle light scattering (MALS), and fluorescence (FS) detectors (AF4-UV-MALS-FS) was employed for separation and characterization of egg yolk plasma. AF4 provided separation of three major components of the egg yolk plasma i.e. soluble proteins, low density lipoproteins (LDL) and their aggregates, based on their respective hydrodynamic sizes. Identification of LDL was confirmed by staining the sample with a fluorescent dye, Nile Red. The effect of carrier liquids on aggregation of LDL was investigated. Collected fractions of soluble proteins were characterized using sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). Moreover, the effect of heat and enzymatic treatment on egg yolk plasma was investigated. The results suggest that enzymatic treatment with phospholipase A2 (PLA2) significantly enhances the heat stability of LDL. The results show that AF4-UV-MALS-FS is a powerful tool for the fractionation and characterization of egg yolk plasma components. Copyright © 2015 Elsevier Ltd. All rights reserved.

Distribution of sulfamonomethoxine and trimethoprim in egg yolk and white.

PubMed

Bilandžić, Nina; Božić, Đurđica; Kolanović, Božica Solomun; Varenina, Ivana; Cvetnić, Luka; Cvetnić, Željko

2015-07-01

The distribution of sulfamonomethoxine (SMM) and trimethoprim (TMP) in egg yolk and white was measured during and after administration of a SMM/TMP combination in laying hens in doses of 8 g l(-)(1) and 12 g l(-)(1) in drinking water for 7 days. The SMM concentration reached maximal levels on day 2 of the post-treatment period for both doses (μg kg(-)(1)): 5920 and 9453 in yolk; 4831 and 6050 in white, in doses 1 and 2, respectively. Significant differences in the SMM and TMP concentrations between yolk and white in post treatment period were found. SMM dropped below the LOD (1.9 μg kg(-1)) in yolk after day 16 and 19 for doses 1 and 2. TMP reached maximal levels on day 3 after drug administration for doses 1 and 2 (μg kg(-)(1)): 6521 and 7329 in yolk, 1370 and 1539 in white. TMP residues were measured above LOD (0.3 μg kg(-)(1)) in yolk for both doses on day 37 post-treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Adult Langerhans cells derive predominantly from embryonic fetal liver monocytes with a minor contribution of yolk sac-derived macrophages.

PubMed

Hoeffel, Guillaume; Wang, Yilin; Greter, Melanie; See, Peter; Teo, Pearline; Malleret, Benoit; Leboeuf, Marylène; Low, Donovan; Oller, Guillaume; Almeida, Francisca; Choy, Sharon H Y; Grisotto, Marcos; Renia, Laurent; Conway, Simon J; Stanley, E Richard; Chan, Jerry K Y; Ng, Lai Guan; Samokhvalov, Igor M; Merad, Miriam; Ginhoux, Florent

2012-06-04

Langerhans cells (LCs) are the dendritic cells (DCs) of the epidermis, forming one of the first hematopoietic lines of defense against skin pathogens. In contrast to other DCs, LCs arise from hematopoietic precursors that seed the skin before birth. However, the origin of these embryonic precursors remains unclear. Using in vivo lineage tracing, we identify a first wave of yolk sac (YS)-derived primitive myeloid progenitors that seed the skin before the onset of fetal liver hematopoiesis. YS progenitors migrate to the embryo proper, including the prospective skin, where they give rise to LC precursors, and the brain rudiment, where they give rise to microglial cells. However, in contrast to microglia, which remain of YS origin throughout life, YS-derived LC precursors are largely replaced by fetal liver monocytes during late embryogenesis. Consequently, adult LCs derive predominantly from fetal liver monocyte-derived cells with a minor contribution of YS-derived cells. Altogether, we establish that adult LCs have a dual origin, bridging early embryonic and late fetal myeloid development.

Adult Langerhans cells derive predominantly from embryonic fetal liver monocytes with a minor contribution of yolk sac–derived macrophages

PubMed Central

Hoeffel, Guillaume; Wang, Yilin; Greter, Melanie; See, Peter; Teo, Pearline; Malleret, Benoit; Leboeuf, Marylène; Low, Donovan; Oller, Guillaume; Almeida, Francisca; Choy, Sharon H.Y.; Grisotto, Marcos; Renia, Laurent; Conway, Simon J.; Stanley, E. Richard; Chan, Jerry K.Y.; Ng, Lai Guan; Samokhvalov, Igor M.

2012-01-01

Langerhans cells (LCs) are the dendritic cells (DCs) of the epidermis, forming one of the first hematopoietic lines of defense against skin pathogens. In contrast to other DCs, LCs arise from hematopoietic precursors that seed the skin before birth. However, the origin of these embryonic precursors remains unclear. Using in vivo lineage tracing, we identify a first wave of yolk sac (YS)–derived primitive myeloid progenitors that seed the skin before the onset of fetal liver hematopoiesis. YS progenitors migrate to the embryo proper, including the prospective skin, where they give rise to LC precursors, and the brain rudiment, where they give rise to microglial cells. However, in contrast to microglia, which remain of YS origin throughout life, YS-derived LC precursors are largely replaced by fetal liver monocytes during late embryogenesis. Consequently, adult LCs derive predominantly from fetal liver monocyte-derived cells with a minor contribution of YS-derived cells. Altogether, we establish that adult LCs have a dual origin, bridging early embryonic and late fetal myeloid development. PMID:22565823

Cryoprotective and contraceptive properties of egg yolk as an additive in rooster sperm diluents.

PubMed

Santiago-Moreno, Julián; Castaño, Cristina; Toledano-Díaz, Adolfo; Coloma, Miguel A; López-Sebastián, Antonio; Prieto, María T; Campo, Jose L

2012-12-01

The addition of chicken egg yolk to semen extenders is thought to reduce the fertilizing potential of rooster spermatozoa--but not (or at least not as much) that of other avian species. The aim of the present study was to determine whether quail egg yolk, a novel extender additive, provides advantages over chicken egg yolk in the cryopreservation of rooster spermatozoa. Experiments were also performed to determine whether the harmful effect of egg yolk occurs during cryopreservation or during fertilization after artificial insemination. Heterospermic rooster semen samples were divided into aliquots and cooled in a polyvinylpyrrolidone-based medium containing 15% chicken egg yolk, 15% quail egg yolk or no egg yolk at all. The viability of spermatozoa of cooled samples (5 °C) without egg yolk were less viable (P<0.01) than those of samples containing either type of egg yolk. The same aliquots were then cryopreserved for 15 days. Thawed spermatozoa preserved without egg yolk showed lower motility (P<0.001) and viability (P<0.001) than those in samples diluted with either type of egg yolk extender. No eggs were fertilized when hens were inseminated with semen that had been diluted with chicken egg yolk. The fertilization rate was only slightly higher when sperm diluted with quail egg yolk was used (1.5%). The best results were obtained when no egg yolk was used (13.8%). These results show that the addition of egg yolk of either type protects rooster sperm cells against cold shock and during freezing and thawing, but exerts a contraceptive effect in the genital tract of the hen. Copyright © 2012 Elsevier Inc. All rights reserved.

Patterns of maternal yolk hormones in eastern screech owl eggs (Megascops asio)

USGS Publications Warehouse

Hahn, D. Caldwell

2011-01-01

Owl clutches typically hatch asynchronously, and brood size hierarchies develop. In this study, we describe intra-clutch variation of testosterone, androstenedione, estradiol, and corticosterone in Eastern screech owl egg yolks. In order to assess whether these hormones may have originated in the follicle, we also characterize variation of testosterone, androstenedione, and corticosterone within the exterior, intermediate, and interior regions of the yolk. Concentrations of testosterone and androstenedione were distributed relatively evenly across egg lay order with the exception of first-laid eggs that had significantly lower concentrations of both androgens than eggs later in the laying sequence. Corticosterone and estradiol did not vary with laying order. Our results suggest that when food is abundant, yolk hormones are deposited in patterns that minimize sibling differences except to reduce dominance by the first-hatching chick. Testosterone and androstenedione concentrations varied throughout the yolk, while corticosterone was evenly distributed throughout the yolk. This supports a follicular origin for both yolk androgens, and an adrenal origin for yolk corticosterone.

Cryopreservation of Dog Semen in a Tris Extender with 1% or 2% Soya Bean Lecithin as a Replacement of Egg Yolk.

PubMed

Axnér, E; Lagerson, E

2016-04-01

Egg yolk is usually included in extenders used for preservation of dog semen. Lecithin is an interesting animal-protein free alternative to egg yolk for semen preservation. The aim of our study was to evaluate soya bean lecithin for cryopreservation of dog semen. Five ejaculate replicates were divided in three equal parts, centrifuged and each pellet diluted with one of the three Tris-based extenders containing 20% egg yolk, 1% soya bean lecithin or 2% soya bean lecithin. Extended semen was loaded in 0.5-ml straws, cooled and diluted a second time and frozen in liquid nitrogen vapours. Sperm motility parameters (CASA), acrosome integrity (FITC-PNA/PI) and sperm membrane integrity (C-FDA) were evaluated 5 min post-thaw and after 2 and 4 h of incubation. Total motility was significantly better in the egg yolk extender than in any of the lecithin-based extender and was better in the 1% lecithin extender than in the 2% lecithin extender. Sperm membrane integrity was significantly better in the egg yolk extender than in any of the lecithin-based extenders but did not differ significantly between the 1% and 2% lecithin extenders. Acrosome integrity was significantly better in the egg yolk extender than in the 2% lecithin extender but did not differ between the egg yolk extender and the 1% lecithin extender or between the two lecithin extenders. In conclusion, egg yolk was superior to lecithin in our study. The extender with 1% lecithin preserved sperm motility better than the extender with 2% lecithin. © 2016 Blackwell Verlag GmbH.

Cleavage of precursors by the mitochondrial processing peptidase requires a compatible mature protein or an intermediate octapeptide

PubMed Central

1991-01-01

Many precursors of mitochondrial proteins are processed in two successive steps by independent matrix peptidases (MPP and MIP), whereas others are cleaved in a single step by MPP alone. To explain this dichotomy, we have constructed deletions of all or part of the octapeptide characteristic of a twice cleaved precursor (human ornithine transcarbamylase [pOTC]), have exchanged leader peptide sequences between once-cleaved (human methylmalonyl-CoA mutase [pMUT]; yeast F1ATPase beta-subunit [pF1 beta]) and twice-cleaved (pOTC; rat malate dehydrogenase (pMDH); Neurospora ubiquinol-cytochrome c reductase iron-sulfur subunit [pFe/S]) precursors, and have incubated these proteins with purified MPP and MIP. When the octapeptide of pOTC was deleted, or when the entire leader peptide of a once-cleaved precursor (pMUT or pF1 beta) was joined to the mature amino terminus of a twice-cleaved precursor (pOTC or pFe/S), no cleavage was produced by either protease. Cleavage of these constructs by MPP was restored by re- inserting as few as two amino-terminal residues of the octapeptide or of the mature amino terminus of a once-cleaved precursor. We conclude that the mature amino terminus of a twice-cleaved precursor is structurally incompatible with cleavage by MPP; such proteins have evolved octapeptides cleaved by MIP to overcome this incompatibility. PMID:1672532

In silico modeling and experimental evidence of coagulant protein interaction with precursors for nanoparticle functionalization.

PubMed

Okoli, Chuka; Sengottaiyan, Selvaraj; Arul Murugan, N; Pavankumar, Asalapuram R; Agren, Hans; Kuttuva Rajarao, Gunaratna

2013-10-01

The design of novel protein-nanoparticle hybrid systems has applications in many fields of science ranging from biomedicine, catalysis, water treatment, etc. The main barrier in devising such tool is lack of adequate information or poor understanding of protein-ligand chemistry. Here, we establish a new strategy based on computational modeling for protein and precursor linkers that can decorate the nanoparticles. Moringa oleifera (MO2.1) seed protein that has coagulation and antimicrobial properties was used. Superparamagnetic nanoparticles (SPION) with precursor ligands were used for the protein-ligand interaction studies. The molecular docking studies reveal that there are two binding sites, one is located at the core binding site; tetraethoxysilane (TEOS) or 3-aminopropyl trimethoxysilane (APTES) binds to this site while the other one is located at the side chain residues where trisodium citrate (TSC) or Si60 binds to this site. The protein-ligand distance profile analysis explains the differences in functional activity of the decorated SPION. Experimentally, TSC-coated nanoparticles showed higher coagulation activity as compared to TEOS- and APTES-coated SPION. To our knowledge, this is the first report on in vitro experimental data, which endorses the computational modeling studies as a powerful tool to design novel precursors for functionalization of nanomaterials; and develop interface hybrid systems for various applications.

An Extensive Description of the Peptidomic Repertoire of the Hen Egg Yolk Plasma.

PubMed

Arena, Simona; Scaloni, Andrea

2018-03-28

Hen egg is a raw material widely used for the preparation of food,  pharmaceutical and cosmetoceutical products. Dedicated proteomic studies were accomplished on eggshell membrane, egg white, and yolk, identifying the most abundant proteins. No similar peptidomic studies have been performed so far. Only preliminary investigations on bioactive peptides in egg fractions and digestates were accomplished through functional screening assays, characterizing antioxidant, antibacterial, antiviral, immunomodulatory, and antihypertensive preparations and isolated components. This study fills this gap and provides a comprehensive picture of the peptides present in the yolk plasma of different hen egg types after 24 and 264 h of laying, taking advantage of a procedure based on a two-step fractionation followed by combined MALDI-TOF-TOF-MS- and nanoLC-ESI-Q-Orbitrap-MS/MS-based analysis. Six hundred and twenty-eight peptides were characterized as deriving from the proteolytic processing of larger protein components after the physiological action of chicken chymotrypsin-like and pepsin-like enzymes. Structural details on their post-translational modifications were also provided. Identified peptides were subjected to bioinformatic analysis and further compared with available data from the literature, ascertaining 198 peptides associable with putative antihypertensive, antimicrobial, anticancer, antiviral, antibiofilm, anorectic, calcium-binding, and anti-inflammatory activities. This analysis was often confirmative of previous experimental evidence on functional properties of unfractionated preparations or isolated molecules. These results further emphasize the bioactive action of yolk-derived peptides as related to egg consumption, and the potential use of these molecules as additive ingredients in the preparation of functional foods and cosmetics.

[Clear cell carcinoma of the ovary simulating a yolk sac tumor].

PubMed

Bahri, Ibticem; Boudawara, Tahya; Khabir, Abdelmajid; Beyrouti, Mohamed Issam; Frikha, Mounir; Jlidi, Rachid

2003-04-01

Clear cell carcinoma (CCC) of the ovary is uncommon. In young patients, this tumor may simulate a yolk sac tumor. In this case, the morphologic distinction between these tumors is often difficult but the immunohistochemical staining for CA125 and alpha foeto protein (AFP) and the response to chemotherapy are particularly helpful to resolve this problem of differential diagnosis. We report a case of a 17 year old patient who was operated for a tumor of the right ovary. The diagnosis of a yolk sac tumor was first suggested. However, because of the non response to chemotherapy, a second laparotomy was performed; the definitive pathologic examination concluded to the diagnosis of a CCC of the ovary. The young age and the immunohistochemical staining for AFP are unusual and misleading features for a CCC. Our objective about this particular case is to discuss the anatomoclinical aspects of the CCC of the ovary and to prove the role of immunohistochemistry in the differential diagnosis.

Spore coat protein of Bacillus subtilis. Structure and precursor synthesis.

PubMed

Munoz, L; Sadaie, Y; Doi, R H

1978-10-10

The coat protein of Bacillus subtilis spores comprises about 10% of the total dry weight of spores and 25% of the total spore protein. One protein with a molecular weight of 13,000 to 15,000 comprises a major portion of the spore coat. This mature spore coat protein has histidine at its NH2 terminus and is relatively rich in hydrophobic amino acids. Netropsin, and antibiotic which binds to A-T-rich regions of DNA and inhibits sporulation, but not growth, decreased the synthesis of this spore coat protein by 75%. A precursor spore coat protein with a molecular weight of 25,000 is made initially at t1 of sporulation and is converted to the mature spore coat protein with a molecular weight of 13,500 at t2 - t3. These data indicate that the spore coat protein gene is expressed very early in sporulation prior to the modifications of RNA polymerase which have been noted.

Fate of egg proteins during the development of Columba livia domestica embryo.

PubMed

Shbailat, Seba Jamal; Aslan, Ibtisam Omar

2018-01-01

The transfer of egg white into the yolk and consumption of yolk proteins by the embryo are largely unexplored in the pigeon Columba livia domestica. Here, we investigated the route of egg white transfer as well as the degradation and uptake of yolk proteins by the pigeon embryo. Initially, we tested the electrophoretic patterns of proteins in different egg compartments throughout development. Then, we used lysozyme as a reference protein to follow the egg white transfer, and we measured its activity using Micrococcus lysodeikticus as a substrate. Moreover, we determined the general protease activity during different developmental stages in the yolk using casein. Finally, we examined the expression of aminopeptidase-N (APN) and oligopeptide transporter PepT1 genes in the yolk sac membrane (YSM) from incubation day 8 until day 17. Several electrophoretic bands of presumptive egg white proteins appeared in different egg compartments. Also, lysozyme activity was detected chronologically in the egg compartments. It appeared on day 12 in the amniotic and intestinal fluids and on day 14 in the yolk. Moreover, protease activity in the yolk increased significantly on day 14 and thereafter. APN expression was largest on day 8 and reduced generally afterward, whereas PepT1 expression peaked between days 13 and 15 but then reduced substantially. Our results suggest that the egg white proteins move through the amnion and intestine into the yolk where they undergo degradation by the activated proteases. Furthermore, the YSM appears to have a role in protein consumption, and this role decreases toward hatch. © 2018 Wiley Periodicals, Inc.

Amyloid Precursor Protein Processing and Alzheimer’s Disease

PubMed Central

O’Brien, Richard J.; Wong, Philip C.

2011-01-01

Alzheimer’s disease (AD), the leading cause of dementia worldwide, is characterized by the accumulation of the β-amyloid peptide (Aβ) within the brain along with hyperphosphorylated and cleaved forms of the microtubule-associated protein tau. Genetic, biochemical, and behavioral research suggest that physiologic generation of the neurotoxic Aβ peptide from sequential amyloid precursor protein (APP) proteolysis is the crucial step in the development of AD. APP is a single-pass transmembrane protein expressed at high levels in the brain and metabolized in a rapid and highly complex fashion by a series of sequential proteases, including the intramembranous γ-secretase complex, which also process other key regulatory molecules. Why Aβ accumulates in the brains of elderly individuals is unclear but could relate to changes in APP metabolism or Aβ elimination. Lessons learned from biochemical and genetic studies of APP processing will be crucial to the development of therapeutic targets to treat AD. PMID:21456963

Manduca Contactin Regulates Amyloid Precursor Protein-Dependent Neuronal Migration

PubMed Central

Ramaker, Jenna M.; Swanson, Tracy L.

2016-01-01

Amyloid precursor protein (APP) was originally identified as the source of β-amyloid peptides that accumulate in Alzheimer's disease (AD), but it also has been implicated in the control of multiple aspects of neuronal motility. APP belongs to an evolutionarily conserved family of transmembrane proteins that can interact with a variety of adapter and signaling molecules. Recently, we showed that both APP and its insect ortholog [APPL (APP-Like)] directly bind the heterotrimeric G-protein Goα, supporting the model that APP can function as an unconventional Goα-coupled receptor. We also adapted a well characterized assay of neuronal migration in the hawkmoth, Manduca sexta, to show that APPL–Goα signaling restricts ectopic growth within the developing nervous system, analogous to the role postulated for APP family proteins in controlling migration within the mammalian cortex. Using this assay, we have now identified Manduca Contactin (MsContactin) as an endogenous ligand for APPL, consistent with previous work showing that Contactins interact with APP family proteins in other systems. Using antisense-based knockdown protocols and fusion proteins targeting both proteins, we have shown that MsContactin is selectively expressed by glial cells that ensheath the migratory neurons (expressing APPL), and that MsContactin–APPL interactions normally prevent inappropriate migration and outgrowth. These results provide new evidence that Contactins can function as authentic ligands for APP family proteins that regulate APP-dependent responses in the developing nervous system. They also support the model that misregulated Contactin–APP interactions might provoke aberrant activation of Goα and its effectors, thereby contributing to the neurodegenerative sequelae that typify AD. SIGNIFICANCE STATEMENT Members of the amyloid precursor protein (APP) family participate in many aspects of neuronal development, but the ligands that normally activate APP signaling have remained

Imaging residue transfer into egg yolks.

PubMed

Donoghue, D J; Myers, K

2000-12-01

Prediction models for residue transfer into eggs are being developed. Recent results indicate that the developing egg yolk serves as an important storage depot for chemical residues. The current study was conducted to visualize incorporation and potential compartmentalization of drug residues in developing egg yolks. To this end, the drug magnevist was injected into hens to evaluate drug transfer into either early- or late-developing yolks. High-resolution magnetic resonance images (MRI) of drug residues in eggs were acquired using a 1.5 T Siemens Magnetom clinical scanner. A 10-cm circular surface coil was used for receiving the magnetic resonance signal. The eggs were positioned inside the coil cavity for an improved signal to noise ratio (SNR). Gradient-echo images were used to locate the centers of the eggs and to prescribe the position of the high-resolution image slab. The images were recorded using an inversion time (T1) weighted magnetization-prepared, rapid acquisition, gradient-recalled-echo (MPRAGE) pulse sequence. The sequence parameters used were as follows: repetition time (TR) equals 12 ms, echo time (TE) equals 5 ms, field of view (FOV) equals 200, TI = 10 ms, 1.25-mm slice thickness, and a matrix of 200 x 256. Following dosing, images of drug residues in eggs indicate that drugs can be incorporated and compartmentalized into ring structures within individual developing egg yolks. These results have significant human food safety implications because even after only a single dose, sequestered drug residues may be stored and later released to contaminate eggs for days to weeks after dosing.

Large-scale aerosol-assisted synthesis of biofriendly Fe2O3 yolk-shell particles: a promising support for enzyme immobilization

NASA Astrophysics Data System (ADS)

Patel, Sanjay K. S.; Choi, Seung Ho; Kang, Yun Chan; Lee, Jung-Kul

2016-03-01

Multiple-shelled Fe2O3 yolk-shell particles were synthesized using the spray drying method and intended as a suitable support for the immobilization of commercial enzymes such as glucose oxidase (GOx), horseradish peroxidase (HRP), and laccase as model enzymes. Yolk-shell particles have an average diameter of 1-3 μm with pore diameters in the range of 16 to 28 nm. The maximum immobilization of GOx, HRP, and laccase resulted in the enzyme loading of 292, 307 and 398 mg per g of support, respectively. After cross-linking of immobilized laccase by glutaraldehyde, immobilization efficiency was improved from 83.5% to 90.2%. Km and Vmax values were 41.5 μM and 1722 μmol min-1 per mg protein for cross-linked laccase and those for free laccase were 29.3 μM and 1890 μmol min-1 per mg protein, respectively. The thermal stability of the enzyme was enhanced up to 18-fold upon cross-linking, and the enzyme retained 93.1% of residual activity after ten cycles of reuse. The immobilized enzyme has shown up to 32-fold higher stability than the free enzyme towards different solvents and it showed higher efficiency than free laccase in the decolorization of dyes and degradation of bisphenol A. The synthesized yolk-shell particles have 3-fold higher enzyme loading efficiency and lower acute toxicity than the commercial Fe2O3 spherical particles. Therefore, the use of unique yolk-shell structure Fe2O3 particles with multiple-shells will be promising for the immobilization of various enzymes in biotechnological applications with improved electrochemical properties. To the best of our knowledge, this is the first report on the use of one pot synthesized Fe2O3 yolk-shell structure particles for the immobilization of enzymes.Multiple-shelled Fe2O3 yolk-shell particles were synthesized using the spray drying method and intended as a suitable support for the immobilization of commercial enzymes such as glucose oxidase (GOx), horseradish peroxidase (HRP), and laccase as model enzymes

Effects of N-glycan precursor length diversity on quality control of protein folding and on protein glycosylation

PubMed Central

Samuelson, John; Robbins, Phillips W.

2014-01-01

Asparagine-linked glycans (N-glycans) of medically important protists have much to tell us about the evolution of N-glycosylation and of N-glycan-dependent quality control (N-glycan QC) of protein folding in the endoplasmic reticulum. While host N-glycans are built upon a dolichol-pyrophosphate-linked precursor with 14 sugars (Glc3Man9GlcNAc2), protist N-glycan precursors vary from Glc3Man9GlcNAc2 (Acanthamoeba) to Man9GlcNAc2 (Trypanosoma) to Glc3Man5GlcNAc2 (Toxoplasma) to Man5GlcNAc2 (Entamoeba, Trichomonas, and Eimeria) to GlcNAc2 (Plasmodium and Giardia) to zero (Theileria). As related organisms have differing N-glycan lengths (e.g. Toxoplasma, Eimeria, Plasmodium, and Theileria), the present N-glycan variation is based upon secondary loss of Alg genes, which encode enzymes that add sugars to the N-glycan precursor. An N-glycan precursor with Man5GlcNAc2 is necessary but not sufficient for N-glycan QC, which is predicted by the presence of the UDP-glucose:glucosyltransferase (UGGT) plus calreticulin and/or calnexin. As many parasites lack glucose in their N-glycan precursor, UGGT product may be identified by inhibition of glucosidase II. The presence of an armless calnexin in Toxoplasma suggests secondary loss of N-glycan QC from coccidia. Positive selection for N-glycan sites occurs in secreted proteins of organisms with NG-QC and is based upon an increased likelihood of threonine but not serine in the second position versus asparagine. In contrast, there appears to be selection against N-glycan length in Plasmodium and N-glycan site density in Toxoplasma. Finally, there is suggestive evidence for N-glycan-dependent ERAD in Trichomonas, which glycosylates and degrades the exogenous reporter mutant carboxypeptidase Y (CPY*). PMID:25475176

Loss of PiT-1 Results in Abnormal Endocytosis in the Yolk Sac Visceral Endoderm

PubMed Central

Wallingford, Mary C.; Giachelli, Cecilia M.

2014-01-01

PiT-1 protein is a transmembrane sodium-dependent phosphate (Pi) transporter. PiT-1 knock out (KO) embryos die from largely unknown causes by embryonic day (E) 12.5. We tested the hypothesis that PiT-1 is required for endocytosis in the embryonic yolk sac (YS) visceral endoderm (VE). Here we present data supporting that PiT-1 KO results in a YS remodeling defect and decreased endocytosis in the YS VE. The remodeling defect is not due to an upstream cardiomyocyte requirement for PiT-1, as SM22αCre-specific KO of PiT-1 in the developing heart and the YS mesodermal layer (ME) does not recapitulate the PiT-1 global KO phenotype. Furthermore, we find that high levels of PiT-1 protein localize to the YS VE apical membrane. Together these data support that PiT-1 is likely required in YS VE. During normal development maternal immunoglobulin (IgG) is endocytosed into YS VE and accumulates in the apical side of the VE in a specialized lysosome termed the apical vacuole (AV). We have identified a reduction in PiT-1 KO VE cell height and a striking loss of IgG accumulation in the PiT-1 KO VE. The endocytosis genes Tfeb, Lamtor2 and Snx2 are increased at the RNA level. Lysotracker Red staining reveals a loss of distinct AVs, and yolk sacs incubated ex vivo with phRODO Green Dextran for Endocytosis demonstrate a functional loss of endocytosis. As yolk sac endocytosis is controlled in part by microautophagy, but expression of LC3 had not been examined, we investigated LC3 expression during yolk sac development and found stage-specific LC3 RNA expression that is predominantly from the YS VE layer at E9.5. Normalized LC3-II protein levels are decreased in the PiT-1 KO YS, supporting a requirement for PiT-1 in autophagy in the YS. Therefore, we propose the novel idea that PiT-1 is central to the regulation of endocytosis and autophagy in the YS VE. PMID:25138534

Structural basis for precursor protein-directed ribosomal peptide macrocyclization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Kunhua; Condurso, Heather L.; Li, Gengnan

Macrocyclization is a common feature of natural product biosynthetic pathways including the diverse family of ribosomal peptides. Microviridins are architecturally complex cyanobacterial ribosomal peptides that target proteases with potent reversible inhibition. The product structure is constructed via three macrocyclizations catalyzed sequentially by two members of the ATP-grasp family, a unique strategy for ribosomal peptide macrocyclization. Here we describe in detail the structural basis for the enzyme-catalyzed macrocyclizations in the microviridin J pathway of Microcystis aeruginosa. The macrocyclases MdnC and MdnB interact with a conserved α-helix of the precursor peptide using a novel precursor-peptide recognition mechanism. The results provide insight intomore » the unique protein–protein interactions that are key to the chemistry, suggest an origin for the natural combinatorial synthesis of microviridin peptides, and provide a framework for future engineering efforts to generate designed compounds.« less

Yolk Sac Mesenchymal Progenitor Cells from New World Mice (Necromys lasiurus) with Multipotent Differential Potential

PubMed Central

Favaron, Phelipe Oliveira; Mess, Andrea; Will, Sônia Elisabete; Maiorka, Paulo César; de Oliveira, Moacir Franco; Miglino, Maria Angelica

2014-01-01

Fetal membranes are abundant, ethically acceptable and readily accessible sources of stem cells. In particular, the yolk sac is a source of cell lineages that do not express MHCs and are mainly free from immunological incompatibles when transferred to a recipient. Although data are available especially for hematopoietic stem cells in mice and human, whereas other cell types and species are dramatically underrepresented. Here we studied the nature and differentiation potential of yolk sac derived mesenchymal stem cells from a New World mouse, Necromys lasiurus. Explants from mid-gestation were cultured in DMEM-High glucose medium with 10% defined fetal bovine serum. The cells were characterized by standard methods including immunophenotyping by fluorescence and flow cytometry, growth and differentiation potential and tumorigenicity assays. The first adherent cells were observed after 7 days of cell culture and included small, elongated fibroblast-like cells (92.13%) and large, round epithelial-like cells with centrally located nuclei (6.5%). Only the fibroblast-like cells survived the first passages. They were positive to markers for mesenchymal stem cells (Stro-1, CD90, CD105, CD73) and pluripotency (Oct3/4, Nanog) as well as precursors of hematopoietic stem cells (CD117). In differentiation assays, they were classified as a multipotent lineage, because they differentiated into osteogenic, adipogenic, and chondrogenic lineages and, finally, they did not develop tumors. In conclusion, mesenchymal progenitor cells with multipotent differentiation potential and sufficient growth and proliferation abilities were able to be obtained from Necromys yolk sacs, therefore, we inferred that these cells may be promising for a wide range of applications in regenerative medicine. PMID:24918429

An evaluation of soybean lecithin as an alternative to avian egg yolk in the cryopreservation of fish sperm.

PubMed

Yildiz, Cengiz; Bozkurt, Yusuf; Yavas, Ilker

2013-08-01

Plant-derived lecithin has been used as a more sanitary alternative to avian egg yolk in livestock sperm cryopreservation protocols but its efficacy for cryopreserving fish sperm has not previously been tested comparatively. Here various concentrations of soybean lecithin were evaluated for the cryopreservation of carp (Cyprinus carpio) sperm. Sexually mature fish were induced to spermiation and ovulation with ovopel. The extenders were prepared by using 300 mM glucose, 10% DMSO, supplemented with different ratios of lecithin (5%, 10%, 15%, and 20%) and 10% egg yolk (control I). Negative control was made without egg yolk and soybean lecithin (control II). The pooled semen was diluted separately at ratio of 1:3 (v/v) by using egg yolk and soybean-based extenders. Diluted semen placed into 0.25 ml straws were equilibrated at 4 °C for 15 min and frozen in liquid nitrogen vapor. Fertilization was conducted using a ratio of 1 × 10(5)spermatozoa/egg. Supplementation of 10% lecithin to extender showed the best cryoprotective effect for sperm motility and duration of motility against freezing damage compared to 15%, 20% and control II groups (p<0.05). Cryopreserved sperm with extender containing 10% lecithin provided a greater result in terms of fertilization success when compared to extenders containing 20% lecithin or control II (p<0.05). It is concluded that the animal protein-free extender containing 10% soybean lecithin has a similar cryoprotective actions with conventional egg yolk-based extender against freezing damages and fertilization. Therefore, soybean lecithin is a suitable alternative to avian egg yolk for the cryopreservation of fish sperm. Copyright © 2013 Elsevier Inc. All rights reserved.

Salovum egg yolk containing antisecretory factor as an adjunct therapy in severe cholera in adult males: a pilot study.

PubMed

Alam, Nur H; Ashraf, Hasan; Olesen, Maryam; Salam, Mohammed A; Gyr, Niklaus; Meier, Remy

2011-08-01

Cholera involves stimulation of intestinal secretory process in response to cholera toxin leading to profuse watery diarrhoea that might cause death due to dehydration unless timely rehydration therapy is initiated. Efforts to identify and test potential antisecretory agents are ongoing. Antisecretory factor (AF) is a naturally-occurring protein produced in the human secretory organs, including the intestine, with antisectory properties demonstrated in animal and human models of secretory diarrhoea. Salovum egg yolk powder contains antisecretory proteins in a much higher (500 times) concentration than that of normal hen eggs. This is achieved by feeding hens with specially-processed cereals, capable of inducing antisecretory proteins in the yolk. The aim of the study was to examine the effect of Salovum egg yolk powder containing AF in the treatment of adult cholera patients. In an open, randomized controlled trial (pilot study), 40 adult male patients with severe cholera were studied: 20 received standard treatment (oral rehydration solution, antibiotic, and usual hospital diet) plus Salovum egg yolk powder (study group) and 20 received standard treatment alone (control group). All the patients received tablet doxycycline (300 mg) once immediately after randomization. Written informed consent was obtained from each subject before enrollment. The main outcome measures were stool weight and duration of diarrhoea. The demographic and baseline clinical characteristics of the study patients were comparable between the groups. No significant differences were found in the mean stool weight, g/kg of body-weight during the first 24 hours [study vs control group, mean +/- standard deviation (SD), 218 +/- 119 vs 195 +/- 136], second 24 hours (mean +/- SD, 23 +/- 39 vs 22 +/- 34), and cumulative up to 72 hours (mean +/- SD, 245 +/- 152 vs 218 +/- 169). The duration (hours) of diarrhoea after admission in the hospital was also similar in both the groups (mean +/- SD, 33 +/- 14

A simplified method for extracting androgens from avian egg yolks

USGS Publications Warehouse

Kozlowski, C.P.; Bauman, J.E.; Hahn, D.C.

2009-01-01

Female birds deposit significant amounts of steroid hormones into the yolks of their eggs. Studies have demonstrated that these hormones, particularly androgens, affect nestling growth and development. In order to measure androgen concentrations in avian egg yolks, most authors follow the extraction methods outlined by Schwabl (1993. Proc. Nat. Acad. Sci. USA 90:11446-11450). We describe a simplified method for extracting androgens from avian egg yolks. Our method, which has been validated through recovery and linearity experiments, consists of a single ethanol precipitation that produces substantially higher recoveries than those reported by Schwabl.

Green synthesis and characterisation of platinum nanoparticles using quail egg yolk

NASA Astrophysics Data System (ADS)

Nadaroglu, Hayrunnisa; Gungor, Azize Alayli; Ince, Selvi; Babagil, Aynur

2017-02-01

Nanotechnology is extensively used in all parts today. Therefore, nano synthesis is also significant in all explored areas. The results of studies conducted have revealed that nanoparticle synthesis is performed by using both chemical and physical methods. It is well known that these syntheses are carried out at high charge, pressure and temperature in harsh environments. Therefore, this study investigated green synthesis method that sustains more mild conditions. In this study, quail egg yolk having high vitamin and protein content was prepared for green synthesis reaction and used for the synthesis of platinum nanoparticles in the reaction medium. Reaction situations were optimised as a function of pH, temperature, time and concentration by using quail egg yolk. The results showed that the highest platinum nanoparticles were synthesised at 20 °C and pH 6.0 for 4 h. Also, optimal concentration of metal ions was established as 0.5 mM. The synthesised platinum nanoparticles were characterised by using UV spectrum, X-ray diffraction and scanning electron microscope.

Calcium- and polyphosphate-containing acidocalcisomes in chicken egg yolk.

PubMed

Ramos, Isabela B; Miranda, Kildare; Ulrich, Paul; Ingram, Peter; LeFurgey, Ann; Machado, Ednildo A; de Souza, Wanderley; Docampo, Roberto

2010-04-09

Poly P (inorganic polyphosphate) is a polymer formed by P(i) residues linked by high-energy phosphoanhydride bonds. The presence of poly P in bacteria, fungi, algae and protists has been widely recognized, but the distribution of poly P in more complex eukaryotes has been poorly studied. Poly P accumulates, together with calcium, in acidic vesicles or acidocalcisomes in a number of organisms and possesses a diverse array of functions, including roles in stress response, blood clotting, inflammation, calcification, cell proliferation and apoptosis. We report here that a considerable amount of phosphorus in the yolk of chicken eggs is in the form of poly P. DAPI (4',6-diamidino-2-phenylindole) staining showed that poly P is localized mainly in electron-dense vesicles located inside larger vacuoles (compound organelles) that are randomly distributed in the yolk. These internal vesicles were shown to contain calcium, potassium, sodium, magnesium, phosphorus, chlorine, iron and zinc, as detected by X-ray microanalysis and elemental mapping. These vesicles stain with the acidophilic dye Acridine Orange. The presence of poly P in organellar fractions of the egg yolk was evident in agarose gels stained with Toluidine Blue and DAPI. Of the total phosphate (Pi) of yolk organelles, 16% is present in the form of poly P. Total poly P content was not altered during the first 4 days of embryogenesis, but poly P chain length decreased after 1 day of development. The results of the present study identify a novel organelle in chicken egg yolk comprising acidic vesicles with a morphology, physiology and composition similar to those of acidocalcisomes, within larger acidic vacuoles. The elemental composition of these acidocalcisomes is proportionally similar to the elemental composition of the yolk, suggesting that most of these elements are located in these organelles, which might be an important storage compartment in eggs.

Yolk testosterone reduces oxidative damages during postnatal development

PubMed Central

Noguera, José Carlos; Alonso-Alvarez, Carlos; Kim, Sin-Yeon; Morales, Judith; Velando, Alberto

2011-01-01

Conditions experienced during early life can influence the development of an organism and several physiological traits, even in adulthood. An important factor is the level of oxidative stress experienced during early life. In birds, extra-genomic egg substances, such as the testosterone hormone, may exert a widespread influence over the offspring phenotype. Interestingly, testosterone can also upregulate the bioavailability of certain antioxidants but simultaneously increases the susceptibility to oxidative stress in adulthood. However, little is known about the effects of maternally derived yolk testosterone on oxidative stress in developing birds. Here, we investigated the role of yolk testosterone on oxidative stress of yellow-legged gull chicks during their early development by experimentally increasing yolk testosterone levels. Levels of antioxidants, reactive oxygen species and lipid oxidative damage were determined in plasma during nestlings' growth. Our results revealed that, contrary to control chicks, birds hatched from testosterone-treated eggs did not show an increase in the levels of oxidative damage during postnatal development. Moreover, the same birds showed a transient increase in plasma antioxidant levels. Our results suggest that yolk testosterone may shape the oxidative stress-resistance phenotype of the chicks during early development owing to an increase in antioxidant defences and repair processes. PMID:20659922

Phylogenetic appearance of Neuropeptide S precursor proteins in tetrapods

PubMed Central

Reinscheid, Rainer K.

2007-01-01

Sleep and emotional behavior are two hallmarks of vertebrate animal behavior, implying that specialized neuronal circuits and dedicated neurochemical messengers may have been developed during evolution to regulate such complex behaviors. Neuropeptide S (NPS) is a newly identified peptide transmitter that activates a typical G protein-coupled receptor. Central administration of NPS produces profound arousal, enhances wakefulness and suppresses all stages of sleep. In addition, NPS can alleviate behavioral responses to stress by producing anxiolytic-like effects. A bioinformatic analysis of current genome databases revealed that the NPS peptide precursor gene is present in all vertebrates with the exception of fish. A high level of sequence conservation, especially of aminoterminal structures was detected, indicating stringent requirements for agonist-induced receptor activation. Duplication of the NPS precursor gene was only found in one out of two marsupial species with sufficient genome coverage (Monodelphis domestica; opossum), indicating that the duplicated opossum NPS sequence might have arisen as an isolated event. Pharmacological analysis of both Monodelphis NPS peptides revealed that only the closely related NPS peptide retained agonistic activity at NPS receptors. The duplicated precursor might be either a pseudogene or could have evolved different receptor selectivity. Together, these data show that NPS is a relatively recent gene in vertebrate evolution whose appearance might coincide with its specialized physiological functions in terrestrial vertebrates. PMID:17293003

Viral precursor protein P3 and its processed products perform discrete and essential functions in the poliovirus RNA replication complex

USDA-ARS?s Scientific Manuscript database

The differential use of protein precursors and their products is a key strategy used during poliovirus replication. To characterize the role of protein precursors during replication, we examined the complementation profiles of mutants that inhibited 3D polymerase or 3C-RNA binding activity. We showe...

Synthesis of NiO-TiO2 hybrids/mSiO2 yolk-shell architectures embedded with ultrasmall gold nanoparticles for enhanced reactivity

NASA Astrophysics Data System (ADS)

Fang, Jiasheng; Zhang, Yiwei; Zhou, Yuming; Zhao, Shuo; Zhang, Chao; Huang, Mengqiu; Gao, Yan

2017-08-01

Novel NiO-TiO2 hybrids/mSiO2 yolk-shell architectures loaded with ultrasmall Au nanoparticles (STNVS-Au) were developed via the rational synthetic strategy. The hierarchical yolk-shell nanostructures (STNVS) with high surface areas were constructed by a facile "bottom-up" assembly process using SiO2 materials and polymer resins as cores/shells and sacrificial templates, accompanied by a simple hydrothermal incorporation of NiO into uniform amorphous TiO2 layers that were converted to NiO-anatase TiO2 p-n heterojunction hybrids. Then, numerous sub-3 nm Au nanoparticles were post encapsulated within STNVS nanostructures through the low-temperature hydrogen reduction based on the unique deposition-precipitation method with Au(en)2Cl3 compounds as gold precursors. The NiO-TiO2 hybrids alloying with Au nanoparticles were effectively protected and entrapped within STNVS architectures, and interacted with outer mSiO2-Au shells, which comprised the powerful STNVS-Au yolk-shell nanoreactors and produced stronger configural synergies in enhancing the heterogeneous catalysis. Into catalyzing the reduction of 4-nitrophenol to 4-aminophenol, the STNVS-Au was shown with outstanding activity and reusability, and its pristine morphology was well retained during the recycling process.

High Yolk Testosterone Transfer Is Associated with an Increased Female Metabolic Rate.

PubMed

Tschirren, Barbara; Ziegler, Ann-Kathrin; Canale, Cindy I; Okuliarová, Monika; Zeman, Michal; Giraudeau, Mathieu

2016-01-01

Yolk androgens of maternal origin are important mediators of prenatal maternal effects. Although in many species short-term benefits of exposure to high yolk androgen concentrations for the offspring have been observed, females differ substantially in the amount of androgens they transfer to their eggs. It suggests that costs for the offspring or the mother constrain the evolution of maternal hormone transfer. However, to date, the nature of these costs remains poorly understood. Unlike most previous work that focused on potential costs for the offspring, we here investigated whether high yolk testosterone transfer is associated with metabolic costs (i.e., a higher metabolic rate) for the mother. We show that Japanese quail (Coturnix japonica) females that deposit higher testosterone concentrations into their eggs have a higher resting metabolic rate. Because a higher metabolic rate is often associated with a shorter life span, this relationship may explain the negative association between yolk testosterone transfer and female longevity observed in the wild. Our results suggest that metabolic costs for the mother can balance the short-term benefits of yolk testosterone exposure for the offspring, thereby contributing to the maintenance of variation in maternal yolk hormone transfer in natural populations.

Determination of yolk contamination in liquid egg white using Raman spectroscopy.

PubMed

Cluff, K; Konda Naganathan, G; Jonnalagada, D; Mortensen, I; Wehling, R; Subbiah, J

2016-07-01

Purified egg white is an important ingredient in a number of baked and confectionary foods because of its foaming properties. However, yolk contamination in amounts as low as 0.01% can impede the foaming ability of egg white. In this study, we used Raman spectroscopy to evaluate the hypothesis that yolk contamination in egg white could be detected based on its molecular optical properties. Yolk contaminated egg white samples (n = 115) with contamination levels ranging from 0% to 0.25% (on weight basis) were prepared. The samples were excited with a 785 nm laser and Raman spectra from 250 to 3,200 cm(-1) were recorded. The Raman spectra were baseline corrected using an optimized piecewise cubic interpolation on each spectrum and then normalized with a standard normal variate transformation. Samples were randomly divided into calibration (n = 77) and validation (n = 38) data sets. A partial least squares regression (PLSR) model was developed to predict yolk contamination levels, based on the Raman spectral fingerprint. Raman spectral peaks, in the spectral region of 1,080 and 1,666 cm(-1), had the largest influence on detecting yolk contamination in egg white. The PLSR model was able to correctly predict yolk contamination levels with an R(2) = 0.90 in the validation data set. These results demonstrate the capability of Raman spectroscopy for detection of yolk contamination at very low levels in egg white and present a strong case for development of an on-line system to be deployed in egg processing plants. © 2016 Poultry Science Association Inc.

Detailed lipid analysis of yolk platelets of amphibian (Bufo arenarum) oocytes.

PubMed

Buschiazzo, Jorgelina; Bruzzone, Ariana; Alonso, Telma Susana

2003-06-01

Yolk platelets, the principal components of amphibian oocytes, have been generally considered as material reservoirs. Their biochemical composition and function during oogenesis and early development have not been fully elucidated. The aim of this study was to carry out a lipidic characterization of yolk platelets from full-grown Bufo arenarum oocytes. Ovarian oocytes were manually obtained and the subcellular fraction was isolated by centrifugation at low velocity. Lipids were separated by thin-layer chromatography. For compositional analysis, they were derived by methanolysis, being identified and quantified in a gas-liquid chromatograph. Phospholipid content indicates that phosphatidylcholine and phosphatidylethanolamine are the main phospholipids followed by phosphatidylinositol, sphingomyelin, phosphatidylserine, and phosphatidic acid. Phospholipidic profile is similar to that in whole oocytes except for the absence of diphosphatidylglycerol in yolk platelets. Oleic, palmitic, and linoleic acids are the main fatty acids in phosphatidylcholine, and oleic acid is the principal one in phosphatidylethanolamine. In phosphatidic acid, palmitic, estearic, palmitoleic, and oleic acids represent 68 mol% of the total acyl groups. Phosphatidylinositol, enriched in arachidonic acid, is the most unsaturated phospholipid while sphingomyelin shows the lowest unsaturation index. The acyl group distribution in triacylglycerols is similar when yolk platelets and whole oocytes are compared. Polar and neutral lipids of yolk platelets determine the lipidic profile of the whole oocyte. The presence of unusual fatty acids as 14:0, 15:0, 15:1, 17:0, and 17:1 in phospholipids and triacylglycerols may indicate an oxidation mechanism different from beta-oxidation in yolk platelets and/or a structural and functional relation with mitochondria. Given that yolk platelets in amphibian oocytes may act in a dynamic fashion in development, their role should be reconsidered.

Precursor binding to an 880-kDa Toc complex as an early step during active import of protein into chloroplasts.

PubMed

Chen, Kuan-Yu; Li, Hsou-min

2007-01-01

The import of protein into chloroplasts is mediated by translocon components located in the chloroplast outer (the Toc proteins) and inner (the Tic proteins) envelope membranes. To identify intermediate steps during active import, we used sucrose density gradient centrifugation and blue-native polyacrylamide gel electrophoresis (BN-PAGE) to identify complexes of translocon components associated with precursor proteins under active import conditions instead of arrested binding conditions. Importing precursor proteins in solubilized chloroplast membranes formed a two-peak distribution in the sucrose density gradient. The heavier peak was in a similar position as the previously reported Tic/Toc supercomplex and was too large to be analyzed by BN-PAGE. The BN-PAGE analyses of the lighter peak revealed that precursors accumulated in at least two complexes. The first complex migrated at a position close to the ferritin dimer (approximately 880 kDa) and contained only the Toc components. Kinetic analyses suggested that this Toc complex represented an earlier step in the import process than the Tic/Toc supercomplex. The second complex in the lighter peak migrated at the position of the ferritin trimer (approximately 1320 kDa). It contained, in addition to the Toc components, Tic110, Hsp93, and an hsp70 homolog, but not Tic40. Two different precursor proteins were shown to associate with the same complexes. Processed mature proteins first appeared in the membranes at the same fractions as the Tic/Toc supercomplex, suggesting that processing of transit peptides occurs while precursors are still associated with the supercomplex.

Precursor binding to an 880-kDa Toc complex as an early step during active import of protein into chloroplasts

PubMed Central

Chen, Kuan-Yu; Li, Hsou-min

2007-01-01

The import of protein into chloroplasts is mediated by translocon components located in the chloroplast outer (the Toc proteins) and inner (the Tic proteins) envelope membranes. To identify intermediate steps during active import, we used sucrose density gradient centrifugation and blue-native polyacrylamide gel electrophoresis (BN-PAGE) to identify complexes of translocon components associated with precursor proteins under active import conditions instead of arrested binding conditions. Importing precursor proteins in solubilized chloroplast membranes formed a two-peak distribution in the sucrose density gradient. The heavier peak was in a similar position as the previously reported Tic/Toc supercomplex and was too large to be analyzed by BN-PAGE. The BN-PAGE analyses of the lighter peak revealed that precursors accumulated in at least two complexes. The first complex migrated at a position close to the ferritin dimer (approximately 880 kDa) and contained only the Toc components. Kinetic analyses suggested that this Toc complex represented an earlier step in the import process than the Tic/Toc supercomplex. The second complex in the lighter peak migrated at the position of the ferritin trimer (approximately 1320 kDa). It contained, in addition to the Toc components, Tic110, Hsp93, and an hsp70 homolog, but not Tic40. Two different precursor proteins were shown to associate with the same complexes. Processed mature proteins first appeared in the membranes at the same fractions as the Tic/Toc supercomplex, suggesting that processing of transit peptides occurs while precursors are still associated with the supercomplex. PMID:17144891

Super chilling enhances preservation of the freshness of salted egg yolk during long-term storage.

PubMed

Yanagisawa, T; Watanuki, C; Ariizumi, M; Shigematsu, Y; Kobayashi, H; Hasegawa, M; Watanabe, K

2009-03-01

Pasteurized egg yolk with 10% (w/w) salt was stored at 5, -5, -15, -20, and -30 degrees C for 1 to 6 mo, respectively. Changes in generation of volatiles of the stored samples (5 and -5 degrees C for 6 mo) were analyzed by SPME-GC-MS. Emulsifying properties of egg yolk stored at -5, -15, -20, and -30 degrees C for 1 mo, respectively, were also evaluated by measurement of emulsion particle diameters in model emulsions prepared with the yolk samples. In addition, structural changes in low-density lipoprotein (LDL) in the egg yolks dependent on storage conditions for 6 mo were evaluated by (31)P-NMR. Volatile compounds such as hexanal, 2-methylbutanal, and 3-methylbutanal increased in egg yolk during storage at 5 degrees C; however, volatile compounds hardly increased in any samples stored at -5 degrees C (super chilling). The mean emulsion particle diameter in super chilled egg yolk was significantly smaller than that in egg yolk stored at the other lower temperatures. In addition, the results of (31)P-NMR evaluation suggested that prevention of structural changes of LDL resulted in maintenance of emulsifying properties of egg yolk. Thus, these results indicate that super chilling is an effective means of preserving salted egg yolk during long-term storage.

Expression and immunolocalisation of the endocytic receptors megalin and cubilin in the human yolk sac and placenta across gestation☆

PubMed Central

Burke, K.A.; Jauniaux, E.; Burton, G.J.; Cindrova-Davies, T.

2013-01-01

Megalin and cubilin are multifunctional endocytic receptors associated with many transporting epithelia. They play an essential role in transport of nutrients through the visceral yolk sac of rodents during embryogenesis. Here, we immunolocalise them to the endodermal layer of the human yolk sac, and to the syncytiotrophoblast and cytotrophoblast cells of placental villi. In villi, the protein level of both receptors increased with gestation. The mRNA for megalin remained constant, while that encoding cubilin increased with gestation. These results suggest megalin and cubilin may be important in human maternal–fetal transfer, and that they increase across gestation to facilitate this function. PMID:23978537

Egg-yolk protein by-product as a source of ACE-inhibitory peptides obtained with using unconventional proteinase from Asian pumpkin (Cucurbita ficifolia).

PubMed

Eckert, Ewelina; Zambrowicz, Aleksandra; Pokora, Marta; Setner, Bartosz; Dąbrowska, Anna; Szołtysik, Marek; Szewczuk, Zbigniew; Polanowski, Antoni; Trziszka, Tadeusz; Chrzanowska, Józefa

2014-10-14

In the present study angiotensin I-converting enzyme (ACE) inhibitory peptides were isolated from egg-yolk protein preparation (YP). Enzymatic hydrolysis conducted using unconventional enzyme from Cucurbita ficifolia (dose: 1000 U/mg of hydrolyzed YP (E/S (w/w)=1:7.52)) was employed to obtain protein hydrolysates. The 4-h hydrolysate exhibited a significant (IC₅₀=482.5 μg/mL) ACE inhibitory activity. Moreover, hydrolysate showed no cytotoxic activity on human and animal cell lines which makes it a very useful multifunctional method for peptide preparation. The compiled isolation procedure (ultrafiltration, size-exclusion chromatography and RP-HPLC) of bioactive peptides from YP hydrolysate resulted in obtaining peptides with the strong ACE inhibitory activity. One homogeneous and three heterogeneous peptide fractions were identified. The peptides were composed of 9-18 amino-acid residues, including mainly arginine and leucine at the N-terminal positions. To confirm the selected bioactive peptide sequences their analogs were chemically synthesized and tested. Peptide LAPSLPGKPKPD showed the strongest ACE inhibitory activity, with IC₅₀ value of 1.97 μmol/L. Peptides with specific biological activity can be used in pharmaceutical, cosmetic or food industries. Because of their potential role as physiological modulators, as well as theirhigh safety profile, they can be used as natural pharmacological compounds or functional food ingredients. The development of biotechnological solutions to obtain peptides with desired biological activity is already in progress. Studies in this area are focused on using unconventional highly specific enzymes and more efficient methods developed to conduct food process technologies. Natural peptides have many advantages. They are mainly toxicologically safe, have wide spectra of therapeutic actions, exhibit less side effects compared to synthetic drugs and are more efficiently absorbed in the intestinal tract. The complexity of

21 CFR 160.180 - Egg yolks.

Code of Federal Regulations, 2013 CFR

2013-04-01

... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... render the egg yolks free of viable Salmonella microorganisms, and that are not food additives as defined...

21 CFR 160.180 - Egg yolks.

Code of Federal Regulations, 2014 CFR

2014-04-01

... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... render the egg yolks free of viable Salmonella microorganisms, and that are not food additives as defined...

Identification of two structurally related proteins involved in proteolytic processing of precursors targeted to the chloroplast.

PubMed Central

Oblong, J E; Lamppa, G K

1992-01-01

Two proteins of 145 and 143 kDa were identified in pea which co-purify with a chloroplast processing activity that cleaves the precursor for the major light-harvesting chlorophyll binding protein (preLHCP). Antiserum generated against the 145/143 kDa doublet recognizes only these two polypeptides in a chloroplast soluble extract. In immunodepletion experiments the antiserum removed the doublet, and there was a concomitant loss of cleavage of preLHCP as well as of precursors for the small subunit of Rubisco and the acyl carrier protein. The 145 and 143 kDa proteins co-eluted in parallel with the peak of processing activity during all fractionation procedures, but they were not detectable as a homo- or heterodimeric complex. The 145 and 143 kDa proteins were used separately to affinity purify immunoglobulins; each preparation recognized both polypeptides, indicating that they are antigenically related. Wheat chloroplasts contain a soluble species similar in size to the 145/143 kDa doublet. Images PMID:1385116

Does dietary vitamin E or C decrease egg yolk cholesterol?

PubMed

Mohiti-Asli, Maziar; Zaghari, Mojtaba

2010-12-01

An experiment was conducted to determine the effect of dietary vitamin E and C on serum metabolites, yolk cholesterol, egg quality, and performance of layer hens. One hundred sixty-eight commercial Hy-Line W-36 layer hens were randomly divided into seven groups and six replicates with four hens in each. Dietary treatments were introduced after the pre-experimental period (10 days) to adjust egg production. Treatments were levels of vitamin E or C (100, 200, and 400 mg/kg diet) supplementation to the basal diet for 4 weeks, whereas the control group received no supplementation. Egg production, egg weight, and feed consumption were recorded during the study. Shell thickness, Haugh unit score, yolk color, yolk weight, yolk cholesterol, and blood parameters were measured at the end of experiment. There was no significant effect of dietary vitamin E or C on hen performance. Egg yolk cholesterol concentrations decreased linearly by antioxidant vitamin supplementation (P < 0.01). Egg yolk cholesterol reduction did not have any negative effect on egg production rate. Antioxidants, especially vitamin C, increased serum glucose concentration (P < 0.05). Serum total cholesterol content did not change by vitamin supplementation but cholesterol in high-density lipoprotein (HDL-C) decreased and cholesterol in low-density lipoprotein (LDL-C) increased (P < 0.05), as dietary vitamin E or C supplementation increased in diets. These results are in conflict with the previous hypothesis that antioxidants have a role in LDL-C removal from the blood or increasing HDL-C. Vitamin E was more effective than vitamin C in this case and if these results are confirmed by further studies, they may result to revision in researchers' point of view about antioxidant especially in human medicine.

Geographical trends in the yolk carotenoid composition of the pied flycatcher (Ficedula hypoleuca).

PubMed

Eeva, Tapio; Ruuskanen, Suvi; Salminen, Juha-Pekka; Belskii, Eugen; Järvinen, Antero; Kerimov, Anvar; Korpimäki, Erkki; Krams, Indrikis; Moreno, Juan; Morosinotto, Chiara; Mänd, Raivo; Orell, Markku; Qvarnström, Anna; Siitari, Heli; Slater, Fred M; Tilgar, Vallo; Visser, Marcel E; Winkel, Wolfgang; Zang, Herwig; Laaksonen, Toni

2011-02-01

Carotenoids in the egg yolks of birds are considered to be important antioxidants and immune stimulants during the rapid growth of embryos. Yolk carotenoid composition is strongly affected by the carotenoid composition of the female's diet at the time of egg formation. Spatial and temporal differences in carotenoid availability may thus be reflected in yolk concentrations. To assess whether yolk carotenoid concentrations or carotenoid profiles show any large-scale geographical trends or differences among habitats, we collected yolk samples from 16 European populations of the pied flycatcher, Ficedula hypoleuca. We found that the concentrations and proportions of lutein and some other xanthophylls in the egg yolks decreased from Central Europe northwards. The most southern population (which is also the one found at the highest altitude) also showed relatively low carotenoid levels. Concentrations of β-carotene and zeaxanthin did not show any obvious geographical gradients. Egg yolks also contained proportionally more lutein and other xanthophylls in deciduous than in mixed or coniferous habitats. We suggest that latitudinal gradients in lutein and xanthophylls reflect the lower availability of lutein-rich food items in the northern F. hypoleuca populations and in montane southern populations, which start egg-laying earlier relative to tree phenology than the Central European populations. Similarly, among-habitat variation is likely to reflect the better availability of lutein-rich food in deciduous forests. Our study is the first to indicate that the concentration and profile of yolk carotenoids may show large-scale spatial variation among populations in different parts of the species' geographical range. Further studies are needed to test the fitness effects of this geographical variation.

Effects of in-feed egg yolk antibodies on Salmonella shedding, bacterial antibiotic resistance, and health of pigs.

PubMed

Mathew, Alan G; Rattanatabtimtong, Sukanya; Nyachoti, Charles M; Fang, Lin

2009-02-01

To determine effects of anti-Salmonella egg yolk antibodies on shedding and antibiotic resistance of Salmonella enterica Typhimurium, newly weaned pigs were randomly assigned to six dietary treatments. These treatment groups were (i) a control (basal) diet without additives and similar diets with (ii) egg yolk powder derived from chickens challenged with Salmonella Typhimurium antigens, (iii) a commercial egg yolk powder control, (iv) apramycin for 14 days followed by carbadox, (v) oxytetracycline, or (vi) spray-dried plasma protein. Treatments were provided beginning on day 3 of the trial, and all pigs were challenged with 5 ml of 10(8) CFU/ml Salmonella Typhimurium on day 7. Fecal samples were collected on days 0, 7, 8, 12, 14, 21, 58, 88, and 118 for isolation of Salmonella and Escherichia coli to determine shedding and antibiotic resistance patterns. Body weights, white blood cell counts, and plasma concentrations of anti-Salmonella immunoglobulin G and porcine interleukin 1beta were analyzed as indicators of animal health. The percentage of pigs shedding Salmonella was lower for antibiotic treatment groups compared with other groups; however, resistance was greater in E. coli from pigs fed antibiotics than in pigs in other treatment groups. Health and performance indicators (pig weight gains, white blood cell counts, and plasma concentrations of anti-Salmonella antibodies) did not differ between treatment groups. These studies indicate that feeding egg yolk containing anti-Salmonella immunoglobulin Y may not be effective in controlling shedding of Salmonella in pigs.

Does the oviparity-viviparity transition alter the partitioning of yolk in embryonic snakes?

PubMed

Wu, Yan-Qing; Qu, Yan-Fu; Wang, Xue-Ji; Gao, Jian-Fang; Ji, Xiang

2017-11-29

The oviparity-viviparity transition is a major evolutionary event, likely altering the reproductive process of the organisms involved. Residual yolk, a portion of yolk remaining unutilized at hatching or birth as parental investment in care, has been investigated in many oviparous amniotes but remained largely unknown in viviparous species. Here, we used data from 20 (12 oviparous and 8 viviparous) species of snakes to see if the oviparity-viviparity transition alters the partitioning of yolk in embryonic snakes. We used ANCOVA to test whether offspring size, mass and components at hatching or birth differed between the sexes in each species. We used both ordinary least squares and phylogenetic generalized least squares regressions to test whether relationships between selected pairs of offspring components were significant. We used phylogenetic ANOVA to test whether offspring components differed between oviparous and viviparous species and, more specifically, the hypothesis that viviparous snakes invest more in the yolk as parental investment in embryogenesis to produce more well developed offspring that are larger in linear size. In none of the 20 species was sex a significant source of variation in any offspring component examined. Newborn viviparous snakes on average contained proportionally more water and, after accounting for body dry mass, had larger carcasses but smaller residual yolks than did newly hatched oviparous snakes. The rates at which carcass dry mass (CDM) and fat body dry mass (FDM) increased with residual yolk dry mass (YDM) did not differ between newborn oviparous and viviparous snakes. Neither CDM nor FDM differed between newborn oviparous and viviparous snakes after accounting for YDM. Our results are not consistent with the hypothesis that the partitioning of yolk between embryonic and post-embryonic stages differs between snakes that differ in parity mode, but instead show that the partitioning of yolk in embryonic snakes is species

OPTIMIZATION OF A PRECISION-CUT TROUT LIVER TISSUE SLICE ASSAY AS A SCREEN FOR VITELLOGENIN INDUCTION: COMPARISON OF SLIDE INCUBATION TECHNIQUES

EPA Science Inventory

The egg-yolk precursor protein vitellogenin (VTG) is normally only produced in the liver of female rainbow trout (RBT) in response to increasing 17B-estradiol (E2) during sexual maturation. However, its...

Adaptor protein 2–mediated endocytosis of the β-secretase BACE1 is dispensable for amyloid precursor protein processing

PubMed Central

Prabhu, Yogikala; Burgos, Patricia V.; Schindler, Christina; Farías, Ginny G.; Magadár, Javier G.; Bonifacino, Juan S.

2012-01-01

The β-site amyloid precursor protein (APP)–cleaving enzyme 1 (BACE1) is a transmembrane aspartyl protease that catalyzes the proteolytic processing of APP and other plasma membrane protein precursors. BACE1 cycles between the trans-Golgi network (TGN), the plasma membrane, and endosomes by virtue of signals contained within its cytosolic C-terminal domain. One of these signals is the DXXLL-motif sequence DISLL, which controls transport between the TGN and endosomes via interaction with GGA proteins. Here we show that the DISLL sequence is embedded within a longer [DE]XXXL[LI]-motif sequence, DDISLL, which mediates internalization from the plasma membrane by interaction with the clathrin-associated, heterotetrameric adaptor protein 2 (AP-2) complex. Mutation of this signal or knockdown of either AP-2 or clathrin decreases endosomal localization and increases plasma membrane localization of BACE1. Remarkably, internalization-defective BACE1 is able to cleave an APP mutant that itself cannot be delivered to endosomes. The drug brefeldin A reversibly prevents BACE1-catalyzed APP cleavage, ruling out that this reaction occurs in the endoplasmic reticulum (ER) or ER–Golgi intermediate compartment. Taken together, these observations support the notion that BACE1 is capable of cleaving APP in late compartments of the secretory pathway. PMID:22553349

Inter-species variation in yolk steroid levels and a cowbird-host comparison

USGS Publications Warehouse

Hahn, D. Caldwell; Hatfield, Jeffrey S.; Abdelnabi, Mahmoud A.; Wu, Julie M.; Igl, Lawrence D.; Ottinger, Mary A.

2005-01-01

We examined variability in yolk hormone levels among songbird species and the role of yolk steroids as a mechanism for enhanced exploitation of hosts by the parasitic Brown-headed Cowbird Molothrus ater. Within-clutch variation in yolk steroids has been found in several avian species in single species studies, but few comparisons have been made among species. We found a large range of differences in yolk testosterone among the seven passerine species examined, with significant differences between those at the high end (Song Sparrow Melospiza melodia , Red-winged Blackbird Agelaius phoeniceus, and House Sparrow, Passer domesticus ) and those at the low end (Eastern Phoebe Sayornis phoebe, and House Finch Carpodacus mexicanus ). We also found that the testosterone level in cowbird eggs was intermediate in relation to host species levels and was significantly lower than that in three common cowbird hosts (Song Sparrow, Red-winged Blackbird, and House Sparrow), but not significantly different from three others. Geographical comparisons of yolk testosterone levels in all cowbird subspecies and populations from several regions showed no significant differences, though a trend that deserves further exploration was the pattern of lowest level in the ancestral population of cowbirds in the central prairies and of highest level in the northwestern population where range invasion occurred approximately 40 years ago. The levels of 17 betaestradiol were similar in the seven songbird species examined, which is consistent with current hypotheses that this hormone plays a role in embryonic sexual differentiation. Further investigation is needed to determine whether the large differences observed among species in absolute level of yolk testosterone are the relevant focal point or whether target tissue sensitivity differences mediate the effects of this yolk steroid, particularly between parasitic and non-parasitic species.

Amyloid precursor protein interaction network in human testis: sentinel proteins for male reproduction.

PubMed

Silva, Joana Vieira; Yoon, Sooyeon; Domingues, Sara; Guimarães, Sofia; Goltsev, Alexander V; da Cruz E Silva, Edgar Figueiredo; Mendes, José Fernando F; da Cruz E Silva, Odete Abreu Beirão; Fardilha, Margarida

2015-01-16

Amyloid precursor protein (APP) is widely recognized for playing a central role in Alzheimer's disease pathogenesis. Although APP is expressed in several tissues outside the human central nervous system, the functions of APP and its family members in other tissues are still poorly understood. APP is involved in several biological functions which might be potentially important for male fertility, such as cell adhesion, cell motility, signaling, and apoptosis. Furthermore, APP superfamily members are known to be associated with fertility. Knowledge on the protein networks of APP in human testis and spermatozoa will shed light on the function of APP in the male reproductive system. We performed a Yeast Two-Hybrid screen and a database search to study the interaction network of APP in human testis and sperm. To gain insights into the role of APP superfamily members in fertility, the study was extended to APP-like protein 2 (APLP2). We analyzed several topological properties of the APP interaction network and the biological and physiological properties of the proteins in the APP interaction network were also specified by gene ontologyand pathways analyses. We classified significant features related to the human male reproduction for the APP interacting proteins and identified modules of proteins with similar functional roles which may show cooperative behavior for male fertility. The present work provides the first report on the APP interactome in human testis. Our approach allowed the identification of novel interactions and recognition of key APP interacting proteins for male reproduction, particularly in sperm-oocyte interaction.

Offspring sex in a TSD gecko correlates with an interaction between incubation temperature and yolk steroid hormones

NASA Astrophysics Data System (ADS)

Ding, Guo-Hua; Yang, Jing; Wang, Jin; Ji, Xiang

2012-12-01

We incubated eggs of the Japanese gecko Gekko japonicus at three temperatures, and measured yolk testosterone (T) and 17β-estradiol (E2) levels at three time points in embryonic development (oviposition, 1/3 of incubation, and 2/3 of incubation), to examine whether maternal influence on offspring sex via yolk steroid hormone deposition is significant in the species. Eggs incubated at 24 °C and 32 °C produced mostly females, and eggs incubated at 28 °C almost a 50:50 sex ratio of hatchlings. Female-producing eggs were larger than male-producing eggs. Clutches in which eggs were incubated at the same temperature produced mostly same-sex siblings. Yolk T level at laying was negatively related to eggs mass, and yolk E2/T ratio was positively related to egg mass. Results of two-way ANOVA with incubation temperature and stage as the factors show that: yolk E2 level was higher at 32 °C than at 24 °C; yolk T level was higher, whereas yolk E2/T ratio was smaller, at 28 °C than at 24 °C; yolk E2 and T levels were higher at 2/3 than at 1/3 of incubation. Our data in G. japonucus show that: (1) maternal influence on offspring sex via yolk steroid hormone deposition is significant; (2) incubation temperature affects the dynamics of developmental changes in yolk steroid hormones; (3) influences of yolk steroid hormones on offspring sex are secondary relative to incubation temperature effects; and (4) offspring sex correlates with an interaction between incubation temperature and yolk steroid hormones.

Offspring sex in a TSD gecko correlates with an interaction between incubation temperature and yolk steroid hormones.

PubMed

Ding, Guo-Hua; Yang, Jing; Wang, Jin; Ji, Xiang

2012-12-01

We incubated eggs of the Japanese gecko Gekko japonicus at three temperatures, and measured yolk testosterone (T) and 17β-estradiol (E2) levels at three time points in embryonic development (oviposition, 1/3 of incubation, and 2/3 of incubation), to examine whether maternal influence on offspring sex via yolk steroid hormone deposition is significant in the species. Eggs incubated at 24 °C and 32 °C produced mostly females, and eggs incubated at 28 °C almost a 50:50 sex ratio of hatchlings. Female-producing eggs were larger than male-producing eggs. Clutches in which eggs were incubated at the same temperature produced mostly same-sex siblings. Yolk T level at laying was negatively related to eggs mass, and yolk E2/T ratio was positively related to egg mass. Results of two-way ANOVA with incubation temperature and stage as the factors show that: yolk E2 level was higher at 32 °C than at 24 °C; yolk T level was higher, whereas yolk E2/T ratio was smaller, at 28 °C than at 24 °C; yolk E2 and T levels were higher at 2/3 than at 1/3 of incubation. Our data in G. japonucus show that: (1) maternal influence on offspring sex via yolk steroid hormone deposition is significant; (2) incubation temperature affects the dynamics of developmental changes in yolk steroid hormones; (3) influences of yolk steroid hormones on offspring sex are secondary relative to incubation temperature effects; and (4) offspring sex correlates with an interaction between incubation temperature and yolk steroid hormones.

Regulation of amyloid precursor protein processing by its KFERQ motif.

PubMed

Park, Ji-Seon; Kim, Dong-Hou; Yoon, Seung-Yong

2016-06-01

Understanding of trafficking, processing, and degradation mechanisms of amyloid precursor protein (APP) is important because APP can be processed to produce β-amyloid (Aβ), a key pathogenic molecule in Alzheimer's disease (AD). Here, we found that APP contains KFERQ motif at its C-terminus, a consensus sequence for chaperone-mediated autophagy (CMA) or microautophagy which are another types of autophagy for degradation of pathogenic molecules in neurodegenerative diseases. Deletion of KFERQ in APP increased C-terminal fragments (CTFs) and secreted N-terminal fragments of APP and kept it away from lysosomes. KFERQ deletion did not abolish the interaction of APP or its cleaved products with heat shock cognate protein 70 (Hsc70), a protein necessary for CMA or microautophagy. These findings suggest that KFERQ motif is important for normal processing and degradation of APP to preclude the accumulation of APP-CTFs although it may not be important for CMA or microautophagy. [BMB Reports 2016; 49(6): 337-342].

Identification of double-yolked duck egg using computer vision.

PubMed

Ma, Long; Sun, Ke; Tu, Kang; Pan, Leiqing; Zhang, Wei

2017-01-01

The double-yolked (DY) egg is quite popular in some Asian countries because it is considered as a sign of good luck, however, the double yolk is one of the reasons why these eggs fail to hatch. The usage of automatic methods for identifying DY eggs can increase the efficiency in the poultry industry by decreasing egg loss during incubation or improving sale proceeds. In this study, two methods for DY duck egg identification were developed by using computer vision technology. Transmittance images of DY and single-yolked (SY) duck eggs were acquired by a CCD camera to identify them according to their shape features. The Fisher's linear discriminant (FLD) model equipped with a set of normalized Fourier descriptors (NFDs) extracted from the acquired images and the convolutional neural network (CNN) model using primary preprocessed images were built to recognize duck egg yolk types. The classification accuracies of the FLD model for SY and DY eggs were 100% and 93.2% respectively, while the classification accuracies of the CNN model for SY and DY eggs were 98% and 98.8% respectively. The CNN-based algorithm took about 0.12 s to recognize one sample image, which was slightly faster than the FLD-based (about 0.20 s). Finally, this work compared two classification methods and provided the better method for DY egg identification.

Identification of double-yolked duck egg using computer vision

PubMed Central

Ma, Long; Sun, Ke; Tu, Kang; Pan, Leiqing; Zhang, Wei

2017-01-01

The double-yolked (DY) egg is quite popular in some Asian countries because it is considered as a sign of good luck, however, the double yolk is one of the reasons why these eggs fail to hatch. The usage of automatic methods for identifying DY eggs can increase the efficiency in the poultry industry by decreasing egg loss during incubation or improving sale proceeds. In this study, two methods for DY duck egg identification were developed by using computer vision technology. Transmittance images of DY and single-yolked (SY) duck eggs were acquired by a CCD camera to identify them according to their shape features. The Fisher’s linear discriminant (FLD) model equipped with a set of normalized Fourier descriptors (NFDs) extracted from the acquired images and the convolutional neural network (CNN) model using primary preprocessed images were built to recognize duck egg yolk types. The classification accuracies of the FLD model for SY and DY eggs were 100% and 93.2% respectively, while the classification accuracies of the CNN model for SY and DY eggs were 98% and 98.8% respectively. The CNN-based algorithm took about 0.12 s to recognize one sample image, which was slightly faster than the FLD-based (about 0.20 s). Finally, this work compared two classification methods and provided the better method for DY egg identification. PMID:29267387

Mass spectrometry characterization for N-glycosylation of immunoglobulin Y from hen egg yolk.

PubMed

Sheng, Long; He, Zhenjiao; Liu, Yaping; Ma, Meihu; Cai, Zhaoxia

2018-03-01

Immunoglobulin Y (IgY) is a new therapeutic antibody that exists in hen egg yolk. It is a glycoprotein, not much is known about its N-glycan structures, site occupancy and site-specific N-glycosylation. In this study, purified protein from hen egg yolk was identified as IgY based on SDS-PAGE and MALDI-TOF/TOF MS. N-glycan was released from IgY using peptide-N4-(N-acetyl-beta-glucosaminyl) asparagine-amidase treatment, and the molecular weight of IgY was calculated using the difference between the molecular weight of IgY and deglycosylated IgY. Two potential N-Glycosylation sites (ASN 308 and ASN 409 ) were detected on IgY by nanoLC-ESI MS. Sugar chains were separated using normal phase liquid chromatography after fluorescence labeling, and 17 N-glycan structures were confirmed using ESI-MS. The sugar chain pattern contained high-mannose oligosaccharide, hybrid oligosaccharide and complex oligosaccharide. These results could lead to other important information regarding IgY glycosylation. Copyright © 2017 Elsevier B.V. All rights reserved.

Protective effect of egg yolk peptide on bone metabolism.

PubMed

Kim, Hye Kyung; Lee, Sena; Leem, Kang-Hyun

2011-03-01

Osteoporosis is a major health problem worldwide, and most current therapy used in osteoporosis treatment acts by either increasing bone formation or decreasing bone resorption. However, the adverse effects of these therapies may preclude their long-term use. We examined the effects of egg yolk water-soluble peptide (YPEP) on bone metabolism as an alternative to current therapeutic agents in ovariectomized (OVX) rats. In the first step, the in vitro effects of YPEP on bone loss were determined. The proliferation, collagen content, and alkaline phosphatase activity of preosteoblastic MC3T3-E1 cells and osteoclastogenesis from bone marrow-derived precursor cells were measured. The in vivo experiment confirmed the positive effect of YPEP on bone tissue. Three-month-old female Sprague-Dawley rats were either sham operated or ovariectomized and fed commercial chow diet or 0.1% YPEP-supplemented diet for 3 month. YPEP increased preosteoblastic MC3T3-E1 cell proliferation and alkaline phosphatase activity in a dose-dependent manner. Collagen content was also increased by YPEP treatment. Furthermore, YPEP potently suppressed osteoclastogenesis from bone marrow-derived precursor cells. YPEP (100 μg/mL) abolished the formation of osteoclasts positive for tartrate-resistant acid phosphatase. OVX rats supplemented with YPEP showed an osteoprotective effect, as the bone mineral density and cortical thickness in the tibia were increased compared with the OVX controls. Moreover, histological data indicate that YPEP prevented the cancellous bone loss induced by ovariectomy. None of these protective effects were observed in casein-treated rats. The present study suggests that YPEP is a promising alternative to current therapeutic agents for the management of osteoporosis.

Plant polycistronic precursors containing non-homologous microRNAs target transcripts encoding functionally related proteins

PubMed Central

2009-01-01

Background MicroRNAs (miRNAs) are endogenous single-stranded small RNAs that regulate the expression of specific mRNAs involved in diverse biological processes. In plants, miRNAs are generally encoded as a single species in independent transcriptional units, referred to as MIRNA genes, in contrast to animal miRNAs, which are frequently clustered. Results We performed a comparative genomic analysis in three model plants (rice, poplar and Arabidopsis) and characterized miRNA clusters containing two to eight miRNA species. These clusters usually encode miRNAs of the same family and certain share a common evolutionary origin across monocot and dicot lineages. In addition, we identified miRNA clusters harboring miRNAs with unrelated sequences that are usually not evolutionarily conserved. Strikingly, non-homologous miRNAs from the same cluster were predicted to target transcripts encoding related proteins. At least four Arabidopsis non-homologous clusters were expressed as single transcriptional units. Overexpression of one of these polycistronic precursors, producing Ath-miR859 and Ath-miR774, led to the DCL1-dependent accumulation of both miRNAs and down-regulation of their different mRNA targets encoding F-box proteins. Conclusions In addition to polycistronic precursors carrying related miRNAs, plants also contain precursors allowing coordinated expression of non-homologous miRNAs to co-regulate functionally related target transcripts. This mechanism paves the way for using polycistronic MIRNA precursors as a new molecular tool for plant biologists to simultaneously control the expression of different genes. PMID:19951405

The effect of pigeon yolk sac fluid on the growth behavior of calcium carbonate crystals.

PubMed

Song, Juan; Cheng, Haixia; Shen, Xinyu; Tong, Hua

2015-03-01

Previous experiments have proved that thermodynamically unstable calcium carbonate vaterite can exist for long periods in the yolk sac of a pigeon embryo. The aim of this article was to demonstrate the effect of in vitro mineralization of yolk sac fluid on calcium carbonate by direct precipitation. Experiments were conducted using pigeon yolk sac fluid and using lecithin extracted from pigeon yolk sac fluid as a control to investigate the regulating effects of the organic components in the embryo on the formation of the calcium carbonate precipitate. Multiple characterization methods were employed to study the various morphological patterns, sizes, crystal growth, and crystal phase transformations of the calcium carbonate precipitates as regulated by the yolk sac fluid extracted at different stages of incubation. The experimental results demonstrate that as the incubation proceeds towards the later stages, the composition and environmental features of the yolk sac fluid become more favorable for the formation of relatively unstable calcium carbonate phases with high energies of the vaterite state. The experiments conducted with extracted lecithin as the template for crystal growth yielded similar results. A large amount of organic molecules with polar functional groups carried by the yolk sac fluid have strong effects and can both initially induce the crystallization and regulate the aggregation of calcium carbonate. Furthermore, this regulation process is found to be closely related to the lecithin contained in yolk sac fluid. These observations confirm the changes in yolk sac fluid composition during incubation have significant effects on the production of vaterite, which implicates the calcium transport during embryo growth. © 2015 Poultry Science Association Inc.

Vascularization and VEGF expression altered in bovine yolk sacs from IVF and NT technologies.

PubMed

Mess, Andrea Maria; Carreira, Ana Claudia Oliveira; Marinovic de Oliveira, Cláudia; Fratini, Paula; Favaron, Phelipe Oliveira; Barreto, Rodrigo da Silva Nunes; Pfarrer, Christiane; Meirelles, Flávio Vieira; Miglino, Maria Angelica

2017-01-01

Reproductive technologies are widely used in cattle, although many are associated with high-embryonic mortality, especially during early gestation, when the yolk sac undergoes macroscopic changes in structure. We hypothesized that vasculogenesis and angiogenesis are affected, thereby affecting embryonic and placental differentiation. To test this, we studied yolk sac development and gene expression of the vascular endothelial growth factor system (VEGF-A, VEGFR-1/Flt-1, VEGFR-2/KDR). Samples from Days 25 to 40/41 of pregnancy from control cattle (n = 8) and from pregnancies established with IVF, (n = 7) or somatic cell nuclear transfer/clones (n = 5) were examined by histology, immunohistochemistry, and quantitative reverse transcriptase PCR. Yolk sacs in IVF- and nuclear transfer-derived pregnancies were immature. Development of villi was sparse in IVF yolk sacs, whereas vascularization was barely formed in clones and was associated, in part, with thin or interrupted endothelium. Transcript levels of the genes characterized exceed minimum detection limits for all groups, except in the mentioned clone with interrupted endothelium. Levels of mRNA for VEGF-A and VEGFR-2 were significantly higher in IVF yolk sacs. Clones had substantial individual variation in gene expression (both upregulation and downregulation). Our data confirmed the broad range in expression of VEGF genes. Furthermore, overexpression in IVF yolk sacs may compensate for an immature yolk sac structure, whereas in clones, patchy expression may cause structural alterations of blood vessels. In conclusion, we inferred that disturbances of yolk sac vasculature contributed to increased early embryonic mortality of bovine pregnancies established with reproductive technologies. Copyright © 2016 Elsevier Inc. All rights reserved.

Ablation of Prion Protein in Wild Type Human Amyloid Precursor Protein (APP) Transgenic Mice Does Not Alter The Proteolysis of APP, Levels of Amyloid-β or Pathologic Phenotype

PubMed Central

Baybutt, Herbert; Diack, Abigail B.; Kellett, Katherine A. B.; Piccardo, Pedro; Manson, Jean C.

2016-01-01

The cellular prion protein (PrPC) has been proposed to play an important role in the pathogenesis of Alzheimer’s disease. In cellular models PrPC inhibited the action of the β-secretase BACE1 on wild type amyloid precursor protein resulting in a reduction in amyloid-β (Aβ) peptides. Here we have assessed the effect of genetic ablation of PrPC in transgenic mice expressing human wild type amyloid precursor protein (line I5). Deletion of PrPC had no effect on the α- and β-secretase proteolysis of the amyloid precursor protein (APP) nor on the amount of Aβ38, Aβ40 or Aβ42 in the brains of the mice. In addition, ablation of PrPC did not alter Aβ deposition or histopathology phenotype in this transgenic model. Thus using this transgenic model we could not provide evidence to support the hypothesis that PrPC regulates Aβ production. PMID:27447728

Expression of thyroid hormone regulator genes in the yolk sac membrane of the developing chicken embryo

PubMed Central

TOO, Hanny Cho; SHIBATA, Mitsuhiro; YAYOTA, Masato; DARRAS, Veerle M.; IWASAWA, Atsushi

2017-01-01

Thyroid hormones (THs) are essential for the correct development of nearly every structure in the body from the very early stages of development, yet the embryonic thyroid gland is not functional at these stages. To clarify the roles of the egg yolk as a source of THs, the TH content in the yolk and the expression of TH regulator genes in the yolk sac membrane were evaluated throughout the 21-day incubation period of chicken embryos. The yolk TH content (22.3 ng triiodothyronine and 654.7 ng thyroxine per total yolk on day 4 of incubation) decreased almost linearly along with development. Real-time PCR revealed gene expression of transthyretin, a principal TH distributor in the chicken, and of a TH-inactivating iodothyronine deiodinase (DIO3), until the second week of incubation when the embryonic pituitary-thyroid axis is generally thought to start functioning. The TH-activating deiodinase (DIO2) and transmembrane transporter of thyroxine (SLCO1C1) genes were expressed in the last week of incubation, which coincided with a marked increase of circulating thyroxine and a reduction in the yolk sac weight. DIO1, which can remove iodine from inactive THs, was expressed throughout the incubation period. It is assumed that the chicken yolk sac inactivates THs contained abundantly in the yolk and supplies the hormones to the developing embryo in appropriate concentrations until the second week of incubation, while THs may be activated in the yolk sac membrane in the last week of incubation. Additionally, the yolk sac could serve as a source of iodine for the embryo. PMID:28652559

[Laser Raman and infrared spectrum analysis of low-density lipoproteins purified from hen egg yolk].

PubMed

Xue, Hui-jun; Sun, Run-guang; Wang, Xiao-mei; Chang, Yi-guang

2010-11-01

During the experiment, diversified proteins were separated from hen egg yolk by ammonium sulphate rapid fractionation, and pure LDL was obtained after filtrating through Sephadex G-200 chromatography. After the qualitative detection of SDS-PAGE, the authors discovered that LDL consists of five major apoprotein. The Raman and infrared spectrum showed CH2 asymmetric stretching and symmetric stretching mode. However, the authors found C==O stretching vibrations of protein peptide bonds and N+ (CH3)3 asymmetric stretching vibration from the choline group in phospholipids. Laser Raman and infrared spectrum analysis of LDL provided useful information for studying their structure.

Insulin-egg yolk dispersions in self microemulsifying system.

PubMed

Singnurkar, P S; Gidwani, S K

2008-11-01

Formulation of insulin into a microemulsion very often presents a physicochemical instability during their preparation and storage. In order to overcome this lack of stability and facilitate the handling of these colloidal systems, stabilization of insulin in presence of hydrophobic components of a microemulsion appears as the most promising strategy. The present paper reports the use of egg yolk for stabilization of insulin in self microemulsifying dispersions. Insulin loaded egg yolk self microemulsifying dispersions were prepared by lyophilization followed by dispersion into self microemulsifying vehicle. The physicochemical characterization of selfmicroemulsifying dispersions includes such as insulin encapsulation efficiency, in vitro stability of insulin in presence of proteolytic enzymes and in vitro release. The biological activity of insulin from the dispersion was estimated by enzyme-linked immunosorbant assay and in vivo using Wistar diabetic rats. The particle size ranged 1.023±0.316 μm in diameter and insulin encapsulation efficiency was 98.2±0.9 %. Insulin hydrophobic self microemulsifying dispersions suppressed insulin release in pH 7.4 phosphate buffer and shown to protect insulin from enzymatic degradation in vitro in presence of chymotripsin. Egg yolk encapsulated insulin was bioactive, demonstrated through both in vivo and in vitro.

Overexpression of human virus surface glycoprotein precursors induces cytosolic unfolded protein response in Saccharomyces cerevisiae

PubMed Central

2011-01-01

Background The expression of human virus surface proteins, as well as other mammalian glycoproteins, is much more efficient in cells of higher eukaryotes rather than yeasts. The limitations to high-level expression of active viral surface glycoproteins in yeast are not well understood. To identify possible bottlenecks we performed a detailed study on overexpression of recombinant mumps hemagglutinin-neuraminidase (MuHN) and measles hemagglutinin (MeH) in yeast Saccharomyces cerevisiae, combining the analysis of recombinant proteins with a proteomic approach. Results Overexpressed recombinant MuHN and MeH proteins were present in large aggregates, were inactive and totally insoluble under native conditions. Moreover, the majority of recombinant protein was found in immature form of non-glycosylated precursors. Fractionation of yeast lysates revealed that the core of viral surface protein aggregates consists of MuHN or MeH disulfide-linked multimers involving eukaryotic translation elongation factor 1A (eEF1A) and is closely associated with small heat shock proteins (sHsps) that can be removed only under denaturing conditions. Complexes of large Hsps seem to be bound to aggregate core peripherally as they can be easily removed at high salt concentrations. Proteomic analysis revealed that the accumulation of unglycosylated viral protein precursors results in specific cytosolic unfolded protein response (UPR-Cyto) in yeast cells, characterized by different action and regulation of small Hsps versus large chaperones of Hsp70, Hsp90 and Hsp110 families. In contrast to most environmental stresses, in the response to synthesis of recombinant MuHN and MeH, only the large Hsps were upregulated whereas sHsps were not. Interestingly, the amount of eEF1A was also increased during this stress response. Conclusions Inefficient translocation of MuHN and MeH precursors through ER membrane is a bottleneck for high-level expression in yeast. Overexpression of these recombinant

Detection of egg yolk antibodies reflecting Salmonella enteritidis infections using a surface plasmon resonance biosensor.

PubMed

Thomas, Ekelijn; Bouma, Annemarie; van Eerden, Ellen; Landman, Wil J M; van Knapen, Frans; Stegeman, Arjan; Bergwerff, Aldert A

2006-08-31

A surface plasmon resonance (SPR) biosensor assay was developed on the basis of a lipopolysaccharide antigen of Salmonella enterica serovar enteritidis (S. enterica serovar enteritidis) to detect egg yolk antibodies against S. enterica serovar enteritidis. This biosensor assay was compared to two commercial ELISA kits based on LPS antigen and flagellar antigen. A number of 163 egg yolk and combined egg white and yolk samples from chickens experimentally infected with S. enterica serovar enteritidis and 90 egg yolk and combined egg white and yolk samples from uninfected chickens were analyzed. Receiver operating characteristic analysis of the data calculated a diagnostic sensitivity of 82% and a diagnostic specificity of 100%. The within-day coefficient of variation of a positive internal-control egg yolk was 1%. The SPR biosensor assay was able to detect antibodies in a significantly higher percentage of known positive samples than the commercial ELISA's. The anticipated use of the SPR biosensor assay is to determine the S. enterica serovar enteritidis serostatus of non-vaccinated layer hens.

Natural Modulators of Amyloid-Beta Precursor Protein Processing

PubMed Central

Zhang, Can; Tanzi, Rudolph E.

2013-01-01

Alzheimer’s disease (AD) is a devastating neurodegenerative disease and the primary cause of dementia, with no cure currently available. The pathogenesis of AD is believed to be primarily driven by Aβ, the principal component of senile plaques. Aβ is an ~4 kDa peptide generated from the amyloid-β precursor protein (APP) through proteolytic secretases. Natural products, particularly those utilized in traditional Chinese medicine (TCM), have a long history alleviating common clinical disorders, including dementia. However, the cell/molecular pathways mediated by these natural products are largely unknown until recently when the underlying molecular mechanisms of the disorders begin to be elucidated. Here, the mechanisms with which natural products modulate the pathogenesis of AD are discussed, in particular, by focusing on their roles in the processing of APP. PMID:22998566

Reproductive adverse outcome pathways for chemical inhibitors of steroid synthesis in fish

EPA Science Inventory

A key physiological process controlling reproductive success of oviparous vertebrates (fish, amphibian, reptiles, birds) involves production of the egg yolk protein precursor vitellogenin (VTG). VTG production is an estrogen receptor (ER)-mediated process that, in females, is con...

Direct Effects of Microalgae and Protists on Herring (Clupea harengus) Yolk Sac Larvae

PubMed Central

Illing, Björn; Moyano, Marta; Niemax, Jan; Peck, Myron A.

2015-01-01

This study investigated effects of microalgae (Rhodomonas baltica) and heterotrophic protists (Oxyrrhis marina) on the daily growth, activity, condition and feeding success of Atlantic herring (Clupea harengus) larvae from hatch, through the end of the endogenous (yolk sac) period. Yolk sac larvae were reared in the presence and absence of microplankton and, each day, groups of larvae were provided access to copepods. Larvae reared with microalgae and protists exhibited precocious (2 days earlier) and ≥ 60% increased feeding incidence on copepods compared to larvae reared in only seawater (SW). In the absence and presence of microalgae and protists, life span and growth trajectories of yolk sac larvae were similar and digestive enzyme activity (trypsin) and nutritional condition (RNA-DNA ratio) markedly declined in all larvae directly after yolk sac depletion. Thus, microplankton promoted early feeding but was not sufficient to alter life span and growth during the yolk sac phase. Given the importance of early feeding, field programs should place greater emphasis on the protozooplankton-ichthyoplankton link to better understand match-mismatch dynamics and bottom-up drivers of year class success in marine fish. PMID:26035592

Direct Effects of Microalgae and Protists on Herring (Clupea harengus) Yolk Sac Larvae.

PubMed

Illing, Björn; Moyano, Marta; Niemax, Jan; Peck, Myron A

2015-01-01

This study investigated effects of microalgae (Rhodomonas baltica) and heterotrophic protists (Oxyrrhis marina) on the daily growth, activity, condition and feeding success of Atlantic herring (Clupea harengus) larvae from hatch, through the end of the endogenous (yolk sac) period. Yolk sac larvae were reared in the presence and absence of microplankton and, each day, groups of larvae were provided access to copepods. Larvae reared with microalgae and protists exhibited precocious (2 days earlier) and ≥ 60% increased feeding incidence on copepods compared to larvae reared in only seawater (SW). In the absence and presence of microalgae and protists, life span and growth trajectories of yolk sac larvae were similar and digestive enzyme activity (trypsin) and nutritional condition (RNA-DNA ratio) markedly declined in all larvae directly after yolk sac depletion. Thus, microplankton promoted early feeding but was not sufficient to alter life span and growth during the yolk sac phase. Given the importance of early feeding, field programs should place greater emphasis on the protozooplankton-ichthyoplankton link to better understand match-mismatch dynamics and bottom-up drivers of year class success in marine fish.

A Novel Pattern of Yolk Processing in Developing Snake Eggs (Colubridae: Lampropeltini) and its Functional and Evolutionary Implications.

PubMed

Powers, Kathryn G; Blackburn, Daniel G

2017-07-01

Early amniotic vertebrates evolved large-yolked eggs that permitted production of well-developed, terrestrial hatchlings. This reproductive pattern required new mechanisms for cellularizing the yolk and mobilizing it for embryonic use. In birds, cells that line the yolk sac cavity phagocytose and digest the yolk material, a pattern that is commonly assumed to be universal among oviparous amniotes. However, recent evidence challenges the assumption that all squamate reptiles conform to the avian developmental pattern. In this paper, scanning electron microscopy and histology were used to study mechanisms of yolk processing in two colubrid snakes, the kingsnake Lampropeltis getula and the milksnake L. triangulum. Endodermal cells from the yolk sac splanchnopleure proliferate massively as they invade the yolk sac cavity, forming elaborate chains of interlinked cells. These cells grow in size as they phagocytose yolk material. Subsequently, vitelline capillaries invade the masses of yolk-laden cells and become coated with the endodermal cells, forming an elaborate meshwork of cell-coated strands. The close association of cells, yolk, and blood vessels allows yolk material to be cellularized, digested, and transported for embryonic use. The overall pattern is like that of the corn snake Pantherophis guttatus, but contrasts markedly with that of birds. Given recent evidence that this developmental pattern may also occur in certain lizards, we postulate that it is ancestral for squamates. Studies of lizards, crocodilians, and turtles are needed to clarify the evolutionary history of this pattern and its implications for the evolution of the amniotic (terrestrial) vertebrate egg. © 2017 Wiley Periodicals, Inc.

Vertical Transmission of a Drosophila Endosymbiont Via Cooption of the Yolk Transport and Internalization Machinery

PubMed Central

Herren, Jeremy K.; Paredes, Juan C.; Schüpfer, Fanny; Lemaitre, Bruno

2013-01-01

ABSTRACT Spiroplasma is a diverse bacterial clade that includes many vertically transmitted insect endosymbionts, including Spiroplasma poulsonii, a natural endosymbiont of Drosophila melanogaster. These bacteria persist in the hemolymph of their adult host and exhibit efficient vertical transmission from mother to offspring. In this study, we analyzed the mechanism that underlies their vertical transmission, and here we provide strong evidence that these bacteria use the yolk uptake machinery to colonize the germ line. We show that Spiroplasma reaches the oocyte by passing through the intercellular space surrounding the ovarian follicle cells and is then endocytosed into oocytes within yolk granules during the vitellogenic stages of oogenesis. Mutations that disrupt yolk uptake by oocytes inhibit vertical Spiroplasma transmission and lead to an accumulation of these bacteria outside the oocyte. Impairment of yolk secretion by the fat body results in Spiroplasma not reaching the oocyte and a severe reduction of vertical transmission. We propose a model in which Spiroplasma first interacts with yolk in the hemolymph to gain access to the oocyte and then uses the yolk receptor, Yolkless, to be endocytosed into the oocyte. Cooption of the yolk uptake machinery is a powerful strategy for endosymbionts to target the germ line and achieve vertical transmission. This mechanism may apply to other endosymbionts and provides a possible explanation for endosymbiont host specificity. PMID:23462112

Rheological behaviour of egg white and egg yolk from different poultry specimen

NASA Astrophysics Data System (ADS)

Kumbár, V.; Nedomová, Š.; Votava, J.; Buchar, J.

2017-01-01

The main goal of this study is differences in rheological behaviour of hen (ISA BROWN), goose (Anser anser f. domestica) and Japanese quail (Coturnix japonica) egg white and egg yolk. The rheological behaviour of egg white and egg yolk was studied using a concentric cylinder viscometer. Rheological behaviour was pseudoplastic and flow curves were fitted by the Herschel-Bulkley model and Ostwald-de Waele model with high values of coeficients of determination R2. The meaning of rheological parameters on friction factors during flow of egg white and egg yolk in real tube has been shown. Preliminary information on time-dependent behaviour of tested liquids has been also obtained.

Biotic and environmental stress induces nitration and changes in structure and function of the sea urchin major yolk protein toposome.

PubMed

Castellano, Immacolata; Migliaccio, Oriana; Ferraro, Giarita; Maffioli, Elisa; Marasco, Daniela; Merlino, Antonello; Zingone, Adriana; Tedeschi, Gabriella; Palumbo, Anna

2018-03-15

The major yolk protein toposome plays crucial roles during gametogenesis and development of sea urchins. We previously found that nitration of toposome increases in the gonads of a Paracentrotus lividus population living in a marine protected area affected by toxic blooms of Ostreospsis cf. ovata, compared to control populations. This modification is associated with ovatoxin accumulation, high levels of nitric oxide in the gonads, and a remarkable impairment of progeny development. However, nothing is known about the environmental-mediated-regulation of the structure and biological function of toposome. Here, we characterize through wide-ranging biochemical and structural analyses the nitrated toposome of sea urchins exposed to the bloom, and subsequently detoxified. The increased number of nitrated tyrosines in toposome of sea urchins collected during algal bloom induced structural changes and improvement of the Ca 2+ -binding affinity of the protein. After 3 months' detoxification, ovatoxin was undetectable, and the number of nitric oxide-modified tyrosines was reduced. However, the nitration of specific residues was irreversible and occurred also in embryos treated with metals, used as a proxy of environmental pollutants. The structural and functional changes of toposome caused by nitration under adverse environmental conditions may be related to the defective development of sea urchins' progeny.

Transfer of Vitamins E and A from yolk to embryo during development of the king penguin (Aptenodytes patagonicus).

PubMed

Surai, P F; Speake, B K; Decrock, F; Groscolas, R

2001-01-01

Since the yolk lipids of the king penguin (Aptenodytes patagonicus) are rich in n-3 fatty acids, which are potentially susceptible to peroxidative damage, the yolk contents and yolk-to-embryo transfer of antioxidants and lipid-soluble vitamins were investigated under conditions of natural incubation in the wild. The concentration of vitamin E in the unincubated egg was 155 microg/g wet yolk, of which 88% was alpha-tocopherol and the rest was gamma-tocopherol. Vitamin A (2.9 microg/g) was present in the yolk entirely as retinol; no retinyl esters were detected. Throughout the latter half of the incubation period, vitamins E and A were taken up from the yolk into the yolk sac membrane (YSM) and later accumulated in the liver, with vitamin A being transferred in advance of vitamin E. In the YSM, vitamin A was present almost entirely as retinyl ester, indicating that the free retinol of the yolk is rapidly esterified following uptake. Retinyl esters were also the predominant form in the liver. The retinyl esters of the liver and YSM displayed different fatty acid profiles. At hatching, the brain contained relatively little vitamin E (4.7 microg/g) compared to the much higher concentration in the liver (482.9 microg/g) at this stage. Ascorbic acid was not detected in the yolk but was present at a high concentration in the brain at day 27 (404.6 microg/g), decreasing to less than half this value by the time of hatching. This report is the first to delineate the yolk-to-embryo transfer of lipid-soluble vitamins for a free-living avian species. The yolk fatty acids of the king penguin provide an extreme example of potential oxidative susceptibility, forming a basis for comparative studies on embryonic antioxidant requirements among species of birds whose yolk lipids differ in their degree of unsaturation.

Morphofunctional transformations of the yolk syncytial layer during zebrafish development.

PubMed

Kondakova, Ekaterina Alexandrovna A; Efremov, Vladimir Ivanovich I

2014-02-01

The yolk syncytial layer (YSL) is a provisory extraembryonic structure of teleost fishes and representatives of some other taxa with meroblastic cleavage. The YSL of teleosts is a symplast with polymorphous polyploid nuclei. It is known to perform nutritional, morphogenetic, immune, and, probably, other functions. Data about the YSL organization, functioning and regulation is fragmentary. Although gene expression patterns and other aspects of YSL functioning have been studied in Danio rerio, the morphology of its YSL has not been described in detail. The study of zebrafish YSL structure on sequential developmental stages is necessary to recognize specific features of this important polyfunctional system in this model organism and to extend our knowledge about provisory systems. The thickness of the YSL and the distribution of its nuclei are not uniform on each stage and change during development. During oblong and sphere stages the internal YSL (I-YSL) is filled with yolk inclusions; interphase yolk syncytial nuclei (YSN) and mitotic asters can be seen. During doming and epiboly the external YSL (E-YSL) is thicker than I-YSL. On the subsequent stages the YSL is thickened caudally. The dorsal YSL part is thickened during early segmentation stages and becomes the thinnest YSL region later. The anterior part of the YSL is thin, but enlarges during larval period. The YSN of different size and diverse forms, from regular to lobed, are present and form clusters. The number of irregular-shaped nuclei increases during development. The YSL thickens in the end of endotrophic and in the course of endo-exotrophic period, and its cytoplasm contains numerous yolk inclusions. After yolk exhaustion the YSL is flat. As the YSL degrades, the YSN become pycnotic, and the YSL remnant probably is cleared by phagocytes. Copyright © 2013 Wiley Periodicals, Inc.

Expression of amyloid-β protein and amyloid-β precursor protein after primary brain-stem injury in rats.

PubMed

Yang, Shudong; Sun, Rongchao; Zhou, Zhiyi; Zhou, Jing; Liang, Jiabei; Mu, Huijun

2014-09-01

Amyloid-β (Aβ) protein and its precursor, amyloid-β precursor protein (β-APP), have traditionally been used in the diagnosis of Alzheimer disease. Their use in diagnosis of traumatic brain injury by forensic analysis is becoming more widespread. However, to date, no reliable small animal model exists to evaluate these brain injury indicators. To address this, we have studied primary brain-stem injury in rats to assess the appearance of diffuse axonal injury in brain sections and correlate these findings with appearance of Aβ and relative β-APP mRNA levels. Using an EnVision 2-step immunohistochemical staining method to measure axon diameter, we found that there was significant difference in axon diameters within the medulla oblongata and several time points after brain injury, ranging from 3 to 24 hours. In addition, mRNA expression levels of β-APP increased following brain injury, peaking 3 hours following injury and decreasing back to baseline levels by 24 hours after injury. These results suggest that using immunohistochemistry and reverse transcription-polymerase chain reaction to detect changes in Aβ-associated axonal changes and β-APP mRNA levels, respectively, can be useful for the diagnosis of diffuse axonal injury during autopsy at early time points following fatal brain injury.

Identification of snake bradykinin-potentiating peptides (BPPs)-simile sequences in rat brain--Potential BPP-like precursor protein?

PubMed

Campeiro, Joana D'Arc; Neshich, Izabella P; Sant'Anna, Osvaldo A; Lopes, Robson; Ianzer, Danielle; Assakura, Marina T; Neshich, Goran; Hayashi, Mirian A F

2015-08-01

Bradykinin-potentiating peptides (BPPs) from the South American pit viper snake venom were the first natural inhibitors of the human angiotensin I-converting enzyme (ACE) described. The pioneer characterization of the BPPs precursor from the snake venom glands by our group showed for the first time the presence of the C-type natriuretic peptide (CNP) in this same viper precursor protein. The confirmation of the BPP/CNP expression in snake brain regions correlated with neuroendocrine functions stimulated us to pursue the physiological correlates of these vasoactive peptides in mammals. Notably, several snake toxins were shown to have endogenous physiological correlates in mammals. In the present work, we expressed in bacteria the BPPs domain of the snake venom gland precursor protein, and this purified recombinant protein was used to raise specific polyclonal anti-BPPs antibodies. The correspondent single protein band immune-recognized in adult rat brain cytosol was isolated by 2D-SDS/PAGE and/or HPLC, before characterization by MS fingerprint analysis, which identified this protein as superoxide dismutase (SOD, EC 1.15.1.1), a classically known enzyme with antioxidant activity and important roles in the blood pressure modulation. In silico analysis showed the exposition of the BPP-like peptide sequences on the surface of the 3D structure of rat SOD. These peptides were chemically synthesized to show the BPP-like biological activities in ex vivo and in vivo pharmacological bioassays. Taken together, our data suggest that SOD protein have the potential to be a source for putative BPP-like bioactive peptides, which once released may contribute to the blood pressure control in mammals. Copyright © 2015 Elsevier Inc. All rights reserved.

Heat-Treatment-Responsive Proteins in Different Developmental Stages of Tomato Pollen Detected by Targeted Mass Accuracy Precursor Alignment (tMAPA).

PubMed

Chaturvedi, Palak; Doerfler, Hannes; Jegadeesan, Sridharan; Ghatak, Arindam; Pressman, Etan; Castillejo, Maria Angeles; Wienkoop, Stefanie; Egelhofer, Volker; Firon, Nurit; Weckwerth, Wolfram

2015-11-06

Recently, we have developed a quantitative shotgun proteomics strategy called mass accuracy precursor alignment (MAPA). The MAPA algorithm uses high mass accuracy to bin mass-to-charge (m/z) ratios of precursor ions from LC-MS analyses, determines their intensities, and extracts a quantitative sample versus m/z ratio data alignment matrix from a multitude of samples. Here, we introduce a novel feature of this algorithm that allows the extraction and alignment of proteotypic peptide precursor ions or any other target peptide from complex shotgun proteomics data for accurate quantification of unique proteins. This strategy circumvents the problem of confusing the quantification of proteins due to indistinguishable protein isoforms by a typical shotgun proteomics approach. We applied this strategy to a comparison of control and heat-treated tomato pollen grains at two developmental stages, post-meiotic and mature. Pollen is a temperature-sensitive tissue involved in the reproductive cycle of plants and plays a major role in fruit setting and yield. By LC-MS-based shotgun proteomics, we identified more than 2000 proteins in total for all different tissues. By applying the targeted MAPA data-processing strategy, 51 unique proteins were identified as heat-treatment-responsive protein candidates. The potential function of the identified candidates in a specific developmental stage is discussed.

Tools to minimize interlaboratory variability in vitellogenin gene expression monitoring programs

EPA Science Inventory

The egg yolk precursor protein vitellogenin is widely used as a biomarker of estrogen exposure in male fish. However, standardized methodology is lacking and little is known regarding the reproducibility of results among laboratories using different equipment, reagents, protocols...

Metabolic fate of yolk fatty acids in the developing king penguin embryo.

PubMed

Groscolas, René; Fréchard, Françoise; Decrock, Frédéric; Speake, Brian K

2003-10-01

This study examines the metabolic fate of total and individual yolk fatty acids (FA) during the embryonic development of the king penguin, a seabird characterized by prolonged incubation (53 days) and hatching (3 days) periods, and a high n-3/n-6 polyunsaturated FA ratio in the egg. Of the approximately 15 g of total FA initially present in the egg lipid, 87% was transferred to the embryo by the time of hatching, the remaining 13% being present in the internalized yolk sac of the chick. During the whole incubation, 83% of the transferred FA was oxidized for energy, with only 17% incorporated into embryo lipids. Prehatching (days 0-49), the fat stores (triacylglycerol) accounted for 58% of the total FA incorporated into embryo lipid. During hatching (days 49-53), 40% of the FA of the fat stores was mobilized, the mobilization of individual FA being nonselective. At hatch, 53% of the arachidonic acid (20:4n-6) of the initial yolk had been incorporated into embryo lipid compared with only 15% of the total FA and 17-24% of the various n-3 polyunsaturated FA. Similarly, only 32% of the yolk's initial content of 20:4n-6 was oxidized for energy during development compared with 72% of the total FA and 58-66% of the n-3 polyunsaturated FA. The high partitioning of yolk FA toward oxidization and the intense mobilization of fat store FA during hatching most likely reflect the high energy cost of the long incubation and hatching periods of the king penguin. The preferential partitioning of 20:4n-6 into the structural lipid of the embryo in the face of its low content in the yolk may reflect the important roles of this FA in tissue function.

Effect of hesperidin dietary supplementation on hen performance, egg quality and yolk oxidative stability.

PubMed

Goliomytis, M; Orfanou, H; Petrou, E; Charismiadou, M A; Simitzis, P E; Deligeorgis, S G

2014-02-01

1. The purpose of this study was to evaluate the effects of dietary supplementation with hesperidin (one or 3 g/kg of feed) for 31 d on the performance, egg quality and yolk oxidative stability of brown and white laying hens (26-wk old). 2. Supplementation with hesperidin did not affect egg production, egg weight and egg quality traits. 3. No hesperidin effect on yolk and plasma cholesterol was observed. A strain effect was found with lower total and per g yolk cholesterol of brown hens in comparison to the white ones. 4. Oxidative stability of egg yolk, expressed as ng MDA/g yolk, was significantly improved in the hesperidin groups even from the first week of supplementation. At the same time, a significant improvement in the oxidative stability of egg yolk due to the incorporation of hesperidin in hens' diet was observed after 30 and 90 d of storage at 20°C and 4°C, respectively. 5. No hesperidin by strain interaction was detected for any of the traits measured. 6. In conclusion, incorporation of hesperidin to laying hens' feed did not affect productive and egg qualitative traits. On the other hand, dietary hesperidin supplementation significantly improved oxidative stability of both fresh and stored eggs. Antioxidant properties of hesperidin seem to make it a promising natural agent for improving the shelf life of eggs.

The Flavivirus Precursor Membrane-Envelope Protein Complex: Structure and Maturation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Long; Lok, Shee-Mei; Yu, I-Mei

2008-09-17

Many viruses go through a maturation step in the final stages of assembly before being transmitted to another host. The maturation process of flaviviruses is directed by the proteolytic cleavage of the precursor membrane protein (prM), turning inert virus into infectious particles. We have determined the 2.2 angstrom resolution crystal structure of a recombinant protein in which the dengue virus prM is linked to the envelope glycoprotein E. The structure represents the prM-E heterodimer and fits well into the cryo-electron microscopy density of immature virus at neutral pH. The pr peptide {beta}-barrel structure covers the fusion loop in E, preventingmore » fusion with host cell membranes. The structure provides a basis for identifying the stages of its pH-directed conformational metamorphosis during maturation, ending with release of pr when budding from the host.« less

21 CFR 160.180 - Egg yolks.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Egg yolks. 160.180 Section 160.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... the method prescribed in “Official Methods of Analysis of the Association of Official Analytical...

Application of a long-established molecular marker in larval teleosts to evaluate estrogenic potential in surface waters and wastewater effluents

EPA Science Inventory

In recent years molecular indicators, diagnostic for exposure in aquatic systems, have been developed using teleostean models in laboratory and field settings. Our laboratory has previously shown that the gene for vitellogenin, a protein precursor of egg yolk in oviparous animals...

Hypothesis testing with computational modeling: linking aromatase inhibition with plasma vitellogenin dynamics in fathead minnows

EPA Science Inventory

Fadrozole inhibits aromatase (CYP19A), a key enzyme that converts testosterone to estradiol (E2). In fish, E2 concentrations control hepatic synthesis ofthe glycolipoprotein vitellogenin (VTG), an egg yolk precursor protein essential to oocyte development and larval survival. Whe...

Computational Modeling to Evaluate Alternative Hypotheses for the Linkage of Aromatase Inhibition to Vitellogenin Levels in Fathead Minnows

EPA Science Inventory

Aromatase converts testosterone to estradiol (E2). In fish, E2 concentrations control hepatic synthesis of the glycolipoprotein vitellogenin (VTG), an egg yolk precursor protein essential to oocyte development and larval survival. Fathead minnows were exposed to the aromatase in...

Cryopreservation of bull semen: Evolution from egg yolk based to soybean based extenders.

PubMed

Layek, S S; Mohanty, T K; Kumaresan, A; Parks, J E

2016-09-01

Since the inception of bovine semen cryopreservation, egg yolk and milk based extenders have been used to protect sperm from the detrimental effects of cooling and freezing. In recent years, demand for alternatives to conventional commercial extenders has arisen as the risk of introducing exotic diseases through transporting egg yolk based products has been recognized. Egg yolk can also interfere with sperm evaluation and the presence of particulate material in the extender may reduce fertility. Soybeans contain lecithin, a phospholipid fraction that can substitute for high molecular weight lipoprotein and phospholipids from egg yolk and prevent or ameliorate damage to the sperm plasma membrane that occurs during extension, cooling, and cryopreservation. Soy lecithin based extenders have been evaluated for processing and freezing bovine semen, although extender from soybean milk has not been studied as extensively. Commercially available soy lecithin based extenders are used increasingly but remain under scrutiny and are not universally accepted. With these observations in mind, this review is intended to examine effects of conventional cryopreservation procedures, methods of assessment, and potential for developing soybean extract as an acceptable alternative to traditional egg yolk and milk based extenders for bull sperm cryopreservation. Copyright © 2016. Published by Elsevier B.V.

21 CFR 160.185 - Dried egg yolks.

Code of Federal Regulations, 2011 CFR

2011-04-01

... preservative. (2) Yeast procedure. The pH of the liquid egg yolks is adjusted to the range of 6.0 to 7.0, if... maintained by adding food-grade baker's yeast (Saccharomyces cerevisiae). The quantity of yeast used and the...

21 CFR 160.185 - Dried egg yolks.

Code of Federal Regulations, 2014 CFR

2014-04-01

... preservative. (2) Yeast procedure. The pH of the liquid egg yolks is adjusted to the range of 6.0 to 7.0, if... maintained by adding food-grade baker's yeast (Saccharomyces cerevisiae). The quantity of yeast used and the...

21 CFR 160.185 - Dried egg yolks.

Code of Federal Regulations, 2013 CFR

2013-04-01

... preservative. (2) Yeast procedure. The pH of the liquid egg yolks is adjusted to the range of 6.0 to 7.0, if... maintained by adding food-grade baker's yeast (Saccharomyces cerevisiae). The quantity of yeast used and the...

21 CFR 160.185 - Dried egg yolks.

Code of Federal Regulations, 2012 CFR

2012-04-01

... preservative. (2) Yeast procedure. The pH of the liquid egg yolks is adjusted to the range of 6.0 to 7.0, if... maintained by adding food-grade baker's yeast (Saccharomyces cerevisiae). The quantity of yeast used and the...

The amyloid precursor protein and postnatal neurogenesis/neuroregeneration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Yanan; Tang, Bor Luen

2006-03-03

The amyloid precursor protein (APP) is the source of amyloid-beta (A{beta}) peptide, produced via its sequential cleavage {beta}- and {gamma}-secretases. Various biophysical forms of A{beta} (and the mutations of APP which results in their elevated levels) have been implicated in the etiology and early onset of Alzheimer's disease. APP's evolutionary conservation and the existence of APP-like isoforms (APLP1 and APLP2) which lack the A{beta} sequence, however, suggest that these might have important physiological functions that are unrelated to A{beta} production. Soluble N-terminal fragments of APP have been known to be neuroprotective, and the interaction of its cytoplasmic C-terminus with amore » myriad of proteins associates it with diverse processes such as axonal transport and transcriptional regulation. The notion for an essential postnatal function of APP has been demonstrated genetically, as mice deficient in both APP and APLP2 or all three APP isoforms exhibit early postnatal lethality and neuroanatomical abnormalities. Recent findings have also brought to light two possible functions of the APP family in Brain-regulation of neural progenitor cell proliferation and axonal outgrowth after injury. Interestingly, these two apparently related neurogenic/neuroregenerative functions of APP involve two separate domains of the molecule.« less

Gels prepared from egg yolk and its fractions for tissue engineering.

PubMed

Rodil, Andrea; Laca, Amanda; Paredes, Benjamín; Rendueles, Manuel; Meana, Álvaro; Díaz, Mario

2016-11-01

New biomaterials prepared from egg yolk and its main fractions (plasma and granules) have been developed for use in tissue engineering. Protein gels obtained via transglutaminase cross-linking were characterized by rheometry, texturometry and scanning electron microscopy. All the gels exhibited suitable physical and mechanical characteristics for use as potential biomaterials in skin regeneration. Specifically, results showed that these materials presented a compact, uniform structure, with granular gel being found to be the most resistant as well as the most elastic material. Accordingly, these gels were subsequently evaluated as scaffolds for murine fibroblast growth. The best results were obtained with granule gels. Not only adhesion and cell growth were detected when using these gels, but also continuous coatings of cells growing on their surface. These findings can be attributed to the higher protein content of this fraction and to the particular structure of its proteins. Thus, granules have proved to be an interesting potential raw material for scaffold development. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1577-1583, 2016. © 2016 American Institute of Chemical Engineers.

Small heat shock proteins are necessary for heart migration and laterality determination in zebrafish

PubMed Central

Lahvic, Jamie L.; Ji, Yongchang; Marin, Paloma; Zuflacht, Jonah P.; Springel, Mark W.; Wosen, Jonathan E.; Davis, Leigh; Hutson, Lara D.; Amack, Jeffrey D.; Marvin, Martha J.

2013-01-01

Small heat shock proteins (sHsps) regulate cellular functions not only under stress, but also during normal development, when they are expressed in organ-specific patterns. Here we demonstrate that two small heat shock proteins expressed in embryonic zebrafish heart, hspb7 and hspb12, have roles in the development of left-right asymmetry. In zebrafish, laterality is determined by the motility of cilia in Kupffer’s vesicle (KV), where hspb7 is expressed; knockdown of hspb7 causes laterality defects by disrupting the motility of these cilia. In embryos with reduced hspb7, the axonemes of KV cilia have a 9+0 structure, while control embyros have a predominately 9+2 structure. Reduction of either hspb7 or hspb12 alters the expression pattern of genes that propagate the signals that establish left-right asymmetry: the nodal-related gene southpaw (spaw) in the lateral plate mesoderm, and its downstream targets pitx2, lefty1 and lefty2. Partial depletion of hspb7 causes concordant heart, brain and visceral laterality defects, indicating that loss of KV cilia motility leads causes coordinated but randomized laterality. Reducing hspb12 leads to similar alterations in the expression of downstream laterality genes, but at a lower penetrance. Simultaneous reduction of hspb7 and hspb12 randomizes heart, brain and visceral laterality, suggesting that these two genes have partially redundant functions in the establishment of left-right asymmetry. In addition, both hspb7 and hspb12 are expressed in the precardiac mesoderm and in the yolk syncytial layer, which supports the migration and fusion of mesodermal cardiac precursors. In embryos in which the reduction of hspb7 or hspb12 was limited to the yolk, migration defects predominated, suggesting that the yolk expression of these genes rather than heart expression is responsible for the migration defects. PMID:24140541

Herpes simplex virus interferes with amyloid precursor protein processing.

PubMed

Shipley, Suzanne J; Parkin, Edward T; Itzhaki, Ruth F; Dobson, Curtis B

2005-08-18

The early events underlying Alzheimer's disease (AD) remain uncertain, although environmental factors may be involved. Work in this laboratory has shown that the combination of herpes simplex virus type 1 (HSV1) in brain and carriage of the APOE-epsilon4 allele of the APOE gene strongly increases the risk of developing AD. The development of AD is thought to involve abnormal aggregation or deposition of a 39-43 amino acid protein--beta amyloid (Abeta)--within the brain. This is cleaved from the much larger transmembranal protein 'amyloid precursor protein' (APP). Any agent able to interfere directly with Abeta or APP metabolism may therefore have the capacity to contribute towards AD. One recent report showed that certain HSV1 glycoprotein peptides may aggregate like Abeta; a second study described a role for APP in transport of virus in squid axons. However to date the effects of acute herpesvirus infection on metabolism of APP in human neuronal-type cells have not been investigated. In order to find if HSV1 directly affects APP and its degradation, we have examined this protein from human neuroblastoma cells (normal and transfected with APP 695) infected with the virus, using Western blotting. We have found that acute HSV1 (and also HSV2) infection rapidly reduces full length APP levels--as might be expected--yet surprisingly markedly increases levels of a novel C-terminal fragment of APP of about 55 kDa. This band was not increased in cells treated with the protein synthesis inhibitor cycloheximide Herpes virus infection leads to rapid loss of full length APP from cells, yet also causes increased levels of a novel 55 kDa C-terminal APP fragment. These data suggest that infection can directly alter the processing of a transmembranal protein intimately linked to the aetiology of AD.

Herpes simplex virus interferes with amyloid precursor protein processing

PubMed Central

Shipley, Suzanne J; Parkin, Edward T; Itzhaki, Ruth F; Dobson, Curtis B

2005-01-01

Background The early events underlying Alzheimer's disease (AD) remain uncertain, although environmental factors may be involved. Work in this laboratory has shown that the combination of herpes simplex virus type 1 (HSV1) in brain and carriage of the APOE-ε4 allele of the APOE gene strongly increases the risk of developing AD. The development of AD is thought to involve abnormal aggregation or deposition of a 39–43 amino acid protein – β amyloid (Aβ) – within the brain. This is cleaved from the much larger transmembranal protein 'amyloid precursor protein' (APP). Any agent able to interfere directly with Aβ or APP metabolism may therefore have the capacity to contribute towards AD. One recent report showed that certain HSV1 glycoprotein peptides may aggregate like Aβ; a second study described a role for APP in transport of virus in squid axons. However to date the effects of acute herpesvirus infection on metabolism of APP in human neuronal-type cells have not been investigated. In order to find if HSV1 directly affects APP and its degradation, we have examined this protein from human neuroblastoma cells (normal and transfected with APP 695) infected with the virus, using Western blotting. Results We have found that acute HSV1 (and also HSV2) infection rapidly reduces full length APP levels – as might be expected – yet surprisingly markedly increases levels of a novel C-terminal fragment of APP of about 55 kDa. This band was not increased in cells treated with the protein synthesis inhibitor cycloheximide Conclusion Herpes virus infection leads to rapid loss of full length APP from cells, yet also causes increased levels of a novel 55 kDa C-terminal APP fragment. These data suggest that infection can directly alter the processing of a transmembranal protein intimately linked to the aetiology of AD. PMID:16109164

Cryopreservation of canine sperm using egg yolk and soy bean based extenders.

PubMed

Sánchez-Calabuig, María Jesús; Maillo, Verónica; Beltrán-Breña, Paula; de la Fuente Martínez, Julio; Galera-Carrillo, Silvestre; Pérez-Gutiérrez, José Félix; Pérez-Cerezales, Serafín

2017-09-01

Animal protein-based extenders are widely used despite being a potential source of bacterial or mycoplasma contamination. Its replacement with vegetal protein-based extenders could represent an interesting alternative for dog sperm cryopreservation. This technique could be further improved by the addition of Tris-Glucose-Citric acid (TGC) that could physically protect the spermatozoa and improve its homeostasis. The aim of this study was to evaluate a cryopreservation protocol for dog spermatozoa using a soybean-based extender (LP1 ℗ ) as well as the effects of the addition of (TGC) immediately after the semen collection. Eleven ejaculates from purebred adult dogs were collected, centrifuged in the absence or presence of TGC and processed as fresh or cryopreserved spermatozoa with: egg yolk-based extender (CaniPRO) or LP1 ℗ . Freezing the spermatozoa in LP1 ℗ reduced the amplitude of the lateral head displacement, the percentage of spermatozoa that showed the intact acrosome and the mitochondrial function (P<0.05). These samples also showed a trend towards increased percentage of apoptotic spermatozoa (P<0.05). The addition of TGC before centrifugation did not improve the seminal parameters and adversely affected motility (P<0.05) in the spermatozoa cryopreserved in CaniPRO. However, TGC did not affect motility and increased (P<0.05) the percentage of intact acrosomes in the spermatozoa cryopreserved in LP1 ℗ , reaching similar values than those cryopreserved in CaniPRO. In conclusion, LP1 ® plus TGC provide the same level of protection to dog spermatozoa cryopreservation than the egg yolk based extender CaniPRO when comparing standard post-thaw sperm quality parameters. Copyright © 2017. Published by Elsevier Urban & Partner Sp. z o.o.

The Effects of Biopolymer Encapsulation on Total Lipids and Cholesterol in Egg Yolk during in Vitro Human Digestion

PubMed Central

Hur, Sun-Jin; Kim, Young-Chan; Choi, Inwook; Lee, Si-Kyung

2013-01-01

The purpose of this study was to examine the effect of biopolymer encapsulation on the digestion of total lipids and cholesterol in egg yolk using an in vitro human digestion model. Egg yolks were encapsulated with 1% cellulose, pectin, or chitosan. The samples were then passed through an in vitro human digestion model that simulated the composition of mouth saliva, stomach acid, and the intestinal juice of the small intestine by using a dialysis tubing system. The change in digestion of total lipids was monitored by confocal fluorescence microscopy. The digestion rate of total lipids and cholesterol in all egg yolk samples dramatically increased after in vitro human digestion. The digestion rate of total lipids and cholesterol in egg yolks encapsulated with chitosan or pectin was reduced compared to the digestion rate of total lipids and cholesterol in other egg yolk samples. Egg yolks encapsulated with pectin or chitosan had lower free fatty acid content, and lipid oxidation values than samples without biopolymer encapsulation. Moreover, the lipase activity decreased, after in vitro digestion, in egg yolks encapsulated with biopolymers. These results improve our understanding of the effects of digestion on total lipids and cholesterol in egg yolk within the gastrointestinal tract. PMID:23965957

A yeast mutant defective at an early stage in import of secretory protein precursors into the endoplasmic reticulum

PubMed Central

1987-01-01

We have devised a genetic selection for mutant yeast cells that fail to translocate secretory protein precursors into the lumen of the endoplasmic reticulum (ER). Mutant cells are selected by a procedure that requires a signal peptide-containing cytoplasmic enzyme chimera to remain in contact with the cytosol. This approach has uncovered a new secretory mutant, sec61, that is thermosensitive for growth and that accumulates multiple secretory and vacuolar precursor proteins that have not acquired any detectable posttranslational modifications associated with translocation into the ER. Preproteins that accumulate at the sec61 block sediment with the particulate fraction, but are exposed to the cytosol as judged by sensitivity to proteinase K. Thus, the sec61 mutation defines a gene that is required for an early cytoplasmic or ER membrane-associated step in protein translocation. PMID:3305520

COMPARISON OF QPCR METHODS FOR THE DETECTION OF VITELLOGENIN EXPRESSION IN FATHEAD MINNOWS

EPA Science Inventory

Male fathead minnows (FHM) normally express little if any of the egg yolk precursor protein vitellogenin (Vg). However, when exposed to estrogenic compounds such as 17a-ethynylestradiol (EE2), transcriptional levels of Vg rise dramatically and result in decreased fecundity and i...

Isolation of Oct4-Expressing Extraembryonic Endoderm Precursor Cell Lines

PubMed Central

Debeb, Bisrat G.; Galat, Vasiliy; Epple-Farmer, Jessica; Iannaccone, Steve; Woodward, Wendy A.; Bader, Michael; Iannaccone, Philip; Binas, Bert

2009-01-01

Background The extraembryonic endoderm (ExEn) defines the yolk sac, a set of membranes that provide essential support for mammalian embryos. Recent findings suggest that the committed ExEn precursor is present already in the embryonic Inner Cell Mass (ICM) as a group of cells that intermingles with the closely related epiblast precursor. All ICM cells contain Oct4, a key transcription factor that is first expressed at the morula stage. In vitro, the epiblast precursor is most closely represented by the well-characterized embryonic stem (ES) cell lines that maintain the expression of Oct4, but analogous ExEn precursor cell lines are not known and it is unclear if they would express Oct4. Methodology/Principal Findings Here we report the isolation and characterization of permanently proliferating Oct4-expressing rat cell lines (“XEN-P cell lines”), which closely resemble the ExEn precursor. We isolated the XEN-P cell lines from blastocysts and characterized them by plating and gene expression assays as well as by injection into embryos. Like ES cells, the XEN-P cells express Oct4 and SSEA1 at high levels and their growth is stimulated by leukemia inhibitory factor, but instead of the epiblast determinant Nanog, they express the ExEn determinants Gata6 and Gata4. Further, they lack markers characteristic of the more differentiated primitive/visceral and parietal ExEn stages, but exclusively differentiate into these stages in vitro and contribute to them in vivo. Conclusions/Significance Our findings (i) suggest strongly that the ExEn precursor is a self-renewable entity, (ii) indicate that active Oct4 gene expression (transcription plus translation) is part of its molecular identity, and (iii) provide an in vitro model of early ExEn differentiation. PMID:19784378

Effects of DHA-enriched hen egg yolk and L-cysteine supplementation on quality of cryopreserved boar semen

PubMed Central

Chanapiwat, Panida; Kaeoket, Kampon; Tummaruk, Padet

2009-01-01

The objective of the present study was to determine the effects of docosahexaenoic acid (DHA)-enriched hen egg yolks and L-cysteine supplementation on the qualities of the cryopreserved boar semen. A total of 15 ejaculates from 5 Pietrain boars were divided into 4 groups according to the compositions of the freezing extenders used, that is, normal hen egg yolk (group I), DHA-enriched hen egg yolk (group II), normal hen egg yolk with 5 mmol L−1 of cysteine supplementation (group III) and DHA-enriched hen egg yolk with 5 mmol L−1 of cysteine supplementation (group IV). The semen was cryopreserved using controlled rate freezer and was thawed at 50°C for 12 s. Progressive motility, sperm viability, acrosome integrity and functional integrity of sperm plasma membrane of the post-thawed semen were evaluated. The supplementation of L-cysteine in the freezing extender alone (group III) improved progressive motility (P < 0.05), and the supplementation of L-cysteine in combination with DHA-enriched hen egg yolk (group IV) improved both progressive motility (P < 0.05) and acrosome integrity (P < 0.01). The use of DHA-enriched hen egg yolk alone (group II) did not enhance any of the post-thawed semen qualities (P > 0.05). In conclusion, the supplementation of antioxidant L-cysteine alone or in combination with DHA-enriched hen egg yolk significantly improved the post-thawed semen qualities, especially progressive motility and acrosome integrity. PMID:19633681

Effects of DHA-enriched hen egg yolk and L-cysteine supplementation on quality of cryopreserved boar semen.

PubMed

Chanapiwat, Panida; Kaeoket, Kampon; Tummaruk, Padet

2009-09-01

The objective of the present study was to determine the effects of docosahexaenoic acid (DHA)-enriched hen egg yolks and L-cysteine supplementation on the qualities of the cryopreserved boar semen. A total of 15 ejaculates from 5 Pietrain boars were divided into 4 groups according to the compositions of the freezing extenders used, that is, normal hen egg yolk (group I), DHA-enriched hen egg yolk (group II), normal hen egg yolk with 5 mmol L(-1) of cysteine supplementation (group III) and DHA-enriched hen egg yolk with 5 mmol L(-1) of cysteine supplementation (group IV). The semen was cryopreserved using controlled rate freezer and was thawed at 50 degrees C for 12 s. Progressive motility, sperm viability, acrosome integrity and functional integrity of sperm plasma membrane of the post-thawed semen were evaluated. The supplementation of L-cysteine in the freezing extender alone (group III) improved progressive motility (P < 0.05), and the supplementation of L-cysteine in combination with DHA-enriched hen egg yolk (group IV) improved both progressive motility (P < 0.05) and acrosome integrity (P < 0.01). The use of DHA-enriched hen egg yolk alone (group II) did not enhance any of the post-thawed semen qualities (P > 0.05). In conclusion, the supplementation of antioxidant L-cysteine alone or in combination with DHA-enriched hen egg yolk significantly improved the post-thawed semen qualities, especially progressive motility and acrosome integrity.

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

Chemical synthesis of the precursor molecule of the Aequorea green fluorescent protein, subsequent folding, and development of fluorescence

PubMed Central

Nishiuchi, Yuji; Inui, Tatsuya; Nishio, Hideki; Bódi, József; Kimura, Terutoshi; Tsuji, Frederick I.; Sakakibara, Shumpei

1998-01-01

The present paper describes the total chemical synthesis of the precursor molecule of the Aequorea green fluorescent protein (GFP). The molecule is made up of 238 amino acid residues in a single polypeptide chain and is nonfluorescent. To carry out the synthesis, a procedure, first described in 1981 for the synthesis of complex peptides, was used. The procedure is based on performing segment condensation reactions in solution while providing maximum protection to the segment. The effectiveness of the procedure has been demonstrated by the synthesis of various biologically active peptides and small proteins, such as human angiogenin, a 123-residue protein analogue of ribonuclease A, human midkine, a 121-residue protein, and pleiotrophin, a 136-residue protein analogue of midkine. The GFP precursor molecule was synthesized from 26 fully protected segments in solution, and the final 238-residue peptide was treated with anhydrous hydrogen fluoride to obtain the precursor molecule of GFP containing two Cys(acetamidomethyl) residues. After removal of the acetamidomethyl groups, the product was dissolved in 0.1 M Tris⋅HCl buffer (pH 8.0) in the presence of DTT. After several hours at room temperature, the solution began to emit a green fluorescence (λmax = 509 nm) under near-UV light. Both fluorescence excitation and fluorescence emission spectra were measured and were found to have the same shape and maxima as those reported for native GFP. The present results demonstrate the utility of the segment condensation procedure in synthesizing large protein molecules such as GFP. The result also provides evidence that the formation of the chromophore in GFP is not dependent on any external cofactor. PMID:9811837

Effects of karaya saponin and Rhodobacter capsulatus on yolk cholesterol in laying hens.

PubMed

Afrose, S; Hossain, M S; Maki, T; Tsujii, H

2010-06-01

1. It has been reported that karaya saponin and Rhodobacter capsulatus individually have hypocholesterolaemic activity in laying hens. This study focuses on the effect of adding karaya saponin with R. capsulatus to hen's diet with regard to serum and egg yolk cholesterol and triglycerides. 2. A total of 56 Boris Brown laying hens were divided into 7 groups at 20 weeks of age. Combinations of 25, 50, 75 mg kg(-1) karaya saponin and R. capsulatus 200 and 400 mg kg(-1) were used as treatment groups. 3. After 8 weeks of supplementation, the effects of all the combinations of karaya saponin and R. capsulatus on serum and egg yolk cholesterol, triglycerides, and high-density lipoprotein (HDL)-cholesterol were greater than either karaya saponin or R. capsulatus alone. The combination of karaya saponin 50 mg kg(-1)+ R. capsulatus 400 mg kg(-1) exhibited the greatest reduction of serum (325%) and yolk (225%) cholesterol and the greatest increase of faecal, liver bile acids and yolk fatty acid (oleic, linoleic and linolenic) concentrations. In addition, egg production and yolk colour were significantly improved by the combined use of karaya saponin and R. capsulatus supplementation. 4. Therefore, the dietary supplementation of karaya saponin and R. capsulatus may lead to the production of a low-cholesterol egg, with production performance maintained at a standard level.

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Procedures for preparing egg yolk... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic... chapter. (a) Under the supervision of an Authorized Agent or State Inspector, the eggs which are used in...

Penguin chicks benefit from elevated yolk androgen levels under sibling competition.

PubMed

Poisbleau, Maud; Müller, Wendt; Carslake, David; Demongin, Laurent; Groothuis, Ton G G; Van Camp, Jeff; Eens, Marcel

2012-01-01

Crested penguins (genus Eudyptes) have a peculiar hatching pattern, with the first-laid egg (A-egg) hatching after the second-laid egg (B-egg) and chicks from A-eggs typically having a much lower survival probability. Maternal yolk androgens have been suggested to contribute to the competitive superiority of the B-chick in southern rockhopper penguins Eudyptes chrysocome, given their important role in mediating sibling competition in other species. We therefore increased the yolk androgen levels in freshly-laid eggs and examined the consequences for sibling competition--via effects on embryonic developmental times, chick growth and early survival. We placed one androgen-treated egg and one control egg into each foster nest, matching them for mass, laying date and laying order. The androgen treatment did not significantly affect embryonic developmental times or chick measurements at hatching. However, elevated yolk androgen levels benefitted chick growth in interaction with the number of siblings in a brood. Chicks from androgen-treated eggs had faster growth in the presence of a sibling than chicks from control eggs. Under these circumstances they also had a higher survival probability. Thus maternal androgens appear to reinforce the observed hatching pattern, facilitating brood reduction. This contrasts to most previous studies in other species where yolk androgens have been shown to compensate for the negative consequences of delayed hatching within the brood hierarchy.

Influence of soy oil source and dietary supplementation of vitamins E and C on the oxidation status of serum and egg yolk, and the lipid profile of egg yolk.

PubMed

Irandoust, H; Ahn, D U

2015-11-01

An experiment was conducted to determine the effects of adding vitamins E and C to diets containing 3.5% refined soy oil (SO), recycled soy oil (RSO), or acidulated soy oil soapstocks (ASS) on 1) fatty acid (FA) profile, and cholesterol, triglyceride (TG) and α-tocopherol (α-T) concentrations of yolk, and 2) the oxidation status of serum and yolk. Twelve dietary treatments, using 3 oil sources, 2 levels of vitamin E (0 vs. 250 mg/kg), and 2 levels of vitamin C (0 vs. 250 mg/kg), were prepared. A total of 300 W36 Hy-line laying hens, from 44 to 56 weeks of age, were placed in 60 cages (5 birds/cage) and 5 cages were randomly assigned to one of the 12 diets. Blood samples and eggs were collected after 84 d on trial. No interactions among main effects were found for any of the traits studied. Oil sources had little effects on the FA profile of the yolk, except for C18:3 that was higher (P-value of < 0.01) in the hens fed SO than those fed RSO or ASS. Vitamin E supplementation significantly (P-value of < 0.05) increased the concentration of C16:0, C18:0, and C16:1 but decreased that of C18:2 and C22:6n3 in the yolk. Vitamin C supplementation significantly (P-value of < 0.05) increased C18:0 and C18:3 concentrations in the yolk but decreased the n6 to n3 FA ratio. The concentrations of cholesterol and triglyceride in serum and yolk were not affected by dietary treatment but α-tocopherol concentration increased (P-value of < 0.01) by the dietary vitamin E. Compared with the hens fed the SO diets, malondialdehyde (MDA) concentration in serum was higher with RSO diet but lower with ASS diet. Vitamin E and vitamin C supplementation decreased (P-value of < 0.05) serum MDA. Yolk FA profile was affected not only by the FA profile of the oil source used in diet, but also by the supplementation of vitamin E and C. The results showed that triglyceride profile, but not cholesterol content, of egg was affected by fatty acid profile of the supplemental oil and the vitamin C and E

Requirement of zebrafish pcdh10a and pcdh10b in melanocyte precursor migration.

PubMed

Williams, Jason S; Hsu, Jessica Y; Rossi, Christy Cortez; Artinger, Kristin Bruk

2018-03-29

Melanocytes derive from neural crest cells, which are a highly migratory population of cells that play an important role in pigmentation of the skin and epidermal appendages. In most vertebrates, melanocyte precursor cells migrate solely along the dorsolateral pathway to populate the skin. However, zebrafish melanocyte precursors also migrate along the ventromedial pathway, in route to the yolk, where they interact with other neural crest derivative populations. Here, we demonstrate the requirement for zebrafish paralogs pcdh10a and pcdh10b in zebrafish melanocyte precursor migration. pcdh10a and pcdh10b are expressed in a subset of melanocyte precursor and somatic cells respectively, and knockdown and TALEN mediated gene disruption of pcdh10a results in aberrant migration of melanocyte precursors resulting in fully melanized melanocytes that differentiate precociously in the ventromedial pathway. Live cell imaging analysis demonstrates that loss of pchd10a results in a reduction of directed cell migration of melanocyte precursors, caused by both increased adhesion and a loss of cell-cell contact with other migratory neural crest cells. Also, we determined that the paralog pcdh10b is upregulated and can compensate for the genetic loss of pcdh10a. Disruption of pcdh10b alone by CRISPR mutagenesis results in somite defects, while the loss of both paralogs results in enhanced migratory melanocyte precursor phenotype and embryonic lethality. These results reveal a novel role for pcdh10a and pcdh10b in zebrafish melanocyte precursor migration and suggest that pcdh10 paralogs potentially interact for proper transient migration along the ventromedial pathway. Copyright © 2018 Elsevier Inc. All rights reserved.

[Chemotherapy of yolk sac tumor heterotransplanted to nude mice (author's transl)].

PubMed

Sawada, M; Hayakawa, K; Matsui, Y; Nishiura, H; Okudaira, Y

1980-10-01

Chemotherapy of yolk sac tumor heterotransplanted to nude mice was studied. 1. Yolk sac tumor of the ovary taken from a 38-year -old woman was transplanted to BALB/c female nude mice. The transplantable tumor cells produce a solid tumor, designated as YST-1 tumor. The YST-1 tumor cells preserve the histological appearance of a human yolk sac tumor and produce x-fetoprotein. The tumors on passage 8 were used for experimental chemotherapy. 2. Anticancer drugs clinically known to be effective for ovarian cancer, such as Adriamycin, Carbazilquinone, 5-Fluorouracil, Cyclophosphamide, Mitomycin C, Chromomycin A3, Vinblastine and Bleomycin were administered intraperitoneally to tumor-bearing nude mice. Tumor size was measured two or three times a week during the course of experiments. Therapeutic effects were evaluated by tumor size and relative tumor size before and after experiments. Among these drugs, Vinblastine and Bleomycin combination showed the significant effect arresting the growth of YST-1 tumor.

Yolk testosterone and corticosterone in hierarchical follicles and laid eggs of Japanese quail exposed to long-term restraint stress.

PubMed

Okuliarová, Monika; Sárniková, Bozena; Rettenbacher, Sophie; Skrobánek, Peter; Zeman, Michal

2010-01-01

Environmental and behavioural stimuli experienced by egg-laying female birds contribute to intra- and inter-female differences in hormones in the egg yolk with consequences for offspring development. The understanding of physiological mechanisms underlying yolk hormone deposition can aid progress in this field. In our study, we measured the concentration of testosterone and corticosterone in hierarchical follicles and egg yolks of Japanese quail in control and chronic stress conditions. Experimental females were reared under hypodynamia, a model situation for restraint stress, from day 3 to 63 days of age. For yolk hormone analysis, four largest follicles of ovarian hierarchy (F1-F4), eggs present in the oviduct and eggs laid on the day before were collected. In chronically stressed birds, yolk testosterone concentrations decreased from F2 onwards, while yolk corticosterone content was increased from the beginning to the end of egg formation. The follicular profile of hormones suggested testosterone transfer into the yolk directly from granulosa and theca cells, with the highest accumulation during a period 48-72 h before laying the egg. Yolk corticosterone was accumulated from maternal plasma preferentially in early stages of follicular development under control conditions and also in last stages of egg formation under stress conditions. These specific patterns of hormone deposition indicate periods when stimuli experienced by female can substantially modify hormonal content of eggs. Lower testosterone and increased corticosterone yolk concentrations in stressed quail may represent signals mediating information about adverse environmental conditions from the mother to progeny.

Development and morphology of the inverted yolk sac in the guinea pig (Cavia porcellus).

PubMed

Vasconcelos, Bruno Gomes; Favaron, Phelipe Oliveira; Miglino, Maria Angelica; Mess, Andrea Maria

2013-10-01

Although the guinea pig is an important animal model for human placentation, aspects of fetal nutrition are not fully understood, especially in regard to the yolk sac that is regarded to be essential for early development of the embryo. We investigated differentiation by means of histology, histochemistry, immunohistochemistry, and transmission electron microscopy. Data suggest that the guinea pig's yolk sac was not sufficiently developed to facilitate substantial fetal nutrition in early pregnancy. On Day 12, it was a flat, inverted, but avascular structure. This was followed by differentiation to form the typical, highly villous and vascularized condition of advanced gestation. Finally, the yolk sac degenerated toward term. We suggest that the guinea pig and other caviomorphs rely predominantly on hemotrophic nutrition via the placenta even in very early pregnancy. In contrast to the general pattern of mammals, histiotrophic nutrition via yolk sac routes seems to be most essential during mid-gestation. Copyright © 2013 Elsevier Inc. All rights reserved.

Implications of genetic selection on yolk proportion on the dry matter content of eggs in a White Leghorn population.

PubMed

Icken, W; Looft, C; Schellander, K; Cavero, D; Blanco, A; Schmutz, M; Preisinger, R

2014-01-01

1. The responses to genetic selection on yolk proportion as a technique for increasing egg dry matter content, an important criterion for the egg-product industry, was investigated in a pedigree flock of White Leghorn hens. 2. Parents were preselected on high and low yolk proportion from a base population. The absolute estimated breeding value for yolk proportion of both groups differed by 3%. The realised selection difference in dry matter content of eggs between groups was more than 1% in the analysed offspring population. 3. Heritability estimates were moderate and dry matter had a lower heritability (h(2) = 0.39) than yolk proportion (h(2) = 0.44). 4. The genetic correlation between yolk proportion and dry matter content was highly positive (rg = 0.91). Genetic correlations with egg weight were negative and would have to be compensated for in a breeding programme (rg = -0.76 with yolk proportion and rg = -0.64 with dry matter content). The genetic correlation between the laying performance and yolk proportion was rg = 0.28 and close to zero (rg = -0.05) for dry matter content. 5. Easy recording and lower undesirable correlations make yolk proportion more suitable for commercial selection compared with egg dry matter content in layer breeding.

Laying-sequence-specific variation in yolk oestrogen levels, and relationship to plasma oestrogen in female zebra finches (Taeniopygia guttata)

PubMed Central

Williams, Tony D.; Ames, Caroline E.; Kiparissis, Yiannis; Wynne-Edwards, Katherine E.

2005-01-01

We investigated the relationship between plasma and yolk oestrogens in laying female zebra finches (Taeniopygia guttata) by manipulating plasma oestradiol (E2) levels, via injection of oestradiol-17β, in a sequence-specific manner to maintain chronically high plasma levels for later-developing eggs (contrasting with the endogenous pattern of decreasing plasma E2 concentrations during laying). We report systematic variation in yolk oestrogen concentrations, in relation to laying sequence, similar to that widely reported for androgenic steroids. In sham-manipulated females, yolk E2 concentrations decreased with laying sequence. However, in E2-treated females plasma E2 levels were higher during the period of rapid yolk development of later-laid eggs, compared with control females. As a consequence, we reversed the laying-sequence-specific pattern of yolk E2: in E2-treated females, yolk E2 concentrations increased with laying-sequence. In general therefore, yolk E2 levels were a direct reflection of plasma E2 levels. However, in control females there was some inter-individual variability in the endogenous pattern of plasma E2 levels through the laying cycle which could generate variation in sequence-specific patterns of yolk hormone levels even if these primarily reflect circulating steroid levels. PMID:15695208

Substitution of egg yolk by a cyclodextrin-cholesterol complex allows a reduction of the glycerol concentration into the freezing medium of equine sperm.

PubMed

Blommaert, Didier; Franck, Thierry; Donnay, Isabelle; Lejeune, Jean-Philippe; Detilleux, Johann; Serteyn, Didier

2016-02-01

The aim of this work was to completely replace the egg yolk a classical diluent for freezing equine semen by a cyclodextrin-cholesterol complex. At the same time, the reduction in the glycerol content used for cryopreservation and the incubation time between sperm and the freezing media were evaluated. Horse ejaculates were frozen with four different freezing extenders: a frozen reference medium (IF) containing egg yolk and 2.5% glycerol and media without egg yolk but supplemented with 1.5 mg 2-hydroxypropyl-beta-cyclodextrin cholesterol (HPβCD-C) complex and containing either 1% (G1), 2% (G2) or 3% glycerol (G3). Three incubation times (90, 120 and 180 min) at 4 °C between the fresh semen and the different media were tested before freezing. Viability and motility analyses were performed with computer assisted semen analysis (CASA). Results showed that the freezing media containing the HPβCD-C complex with 1%, 2% and 3% glycerol significantly improve the 3 in vitro parameters of post thawing semen quality (viability, progressive and total mobilities) compared to IF. The best improvement of the parameters was obtained with G1 medium and the longest contact time. The substitution of egg yolk by HPβCD-C complex allows the decrease of protein charge of the medium while favouring the cholesterol supply to membrane spermatozoa offering it a better resistance to osmotic imbalance and a better tolerance to the glycerol toxicity. Our results highlight that the egg yolk of an extender for the freezing of horse semen can be completely substituted by HPβCD-C complex. Copyright © 2015. Published by Elsevier Inc.

Rhesus monkey sperm cryopreservation with TEST-yolk extender in the absence of permeable cryoprotectant.

PubMed

Dong, Qiaoxiang; Correa, Liane M; VandeVoort, Catherine A

2009-02-01

Recently, there has been increased interest in ultra-rapid freezing with mammalian spermatozoa, especially for vitrification in the absence of cryoprotectants. Sperm cryopreservation in non-human primates has been successful, but the use of frozen-thawed sperm in standard artificial insemination (AI) remains difficult, and removal of permeable cryoprotectant may offer opportunities for increased AI success. The present study intended to explore the possibility of freezing rhesus monkey sperm in the absence of permeable cryoprotectants. Specifically, we evaluated various factors such as presence or absence of egg yolk, the percentage of egg yolk in the extenders, and the effect of cooling and thawing rate on the success of freezing without permeable cryoprotectants. Findings revealed that freezing with TEST in the absence of egg yolk offers little protection (<15% post-thaw motility). Egg yolk of 40% or more in TEST resulted in decreased motility, while egg yolk in the range of 20-30% yielded the most motile sperm. Cooling at a slow rate (29 degrees C/min) reduced post-thaw motility significantly for samples frozen with TEST-yolk alone, but had no effect for controls in the presence of glycerol. Similarly, slow thawing in room temperature air is detrimental for freezing without permeable cryoprotectant (<2% motility). In addition to motility, the ability of sperm to capacitate based on an increase in intracellular calcium levels upon activation with cAMP and caffeine suggested no difference between fresh and frozen-thawed motile sperm, regardless of treatment. In summary, the present study demonstrates that ejaculated and epididymal sperm from rhesus monkeys can be cryopreserved with TEST-yolk (20%) in the absence of permeable cryoprotectant when samples were loaded in a standard 0.25-mL straw, cooled rapidly in liquid nitrogen vapor at 220 degrees C/min, and thawed rapidly in a 37 degrees C water bath. This study also represents the first success of freezing

Nerve Growth Factor Increases mRNA Levels for the Prion Protein and the β -amyloid Protein Precursor in Developing Hamster Brain

NASA Astrophysics Data System (ADS)

Mobley, William C.; Neve, Rachael L.; Prusiner, Stanley B.; McKinley, Michael P.

1988-12-01

Deposition of amyloid filaments serves as a pathologic hallmark for some neurodegenerative disorders. The prion protein (PrP) is found in amyloid of animals with scrapie and humans with Creutzfeldt-Jakob disease; the β protein is present in amyloid deposits in Alzheimer disease and Down syndrome patients. These two proteins are derived from precursors that in the brain are expressed primarily in neurons and are membrane bound. We found that gene expression for PrP and the β -protein precursor (β -PP) is regulated in developing hamster brain. Specific brain regions showed distinct patterns of ontogenesis for PrP and β -PP mRNAs. The increases in PrP and β -PP mRNAs in developing basal forebrain coincided with an increase in choline acetyltransferase activity, raising the possibility that these markers might be coordinately controlled in cholinergic neurons and regulated by nerve growth factor (NGF). Injections of NGF into the brains of neonatal hamsters increased both PrP and β -PP mRNA levels. Increased PrP and β -PP mRNA levels induced by NGF were confined to regions that contain NGF-responsive cholinergic neurons and were accompanied by elevations in choline acetyltransferase. It remains to be established whether or not exogenous NGF acts to increase PrP and β -PP gene expression selectively in forebrain cholinergic neurons in the developing hamster and endogenous NGF regulates expression of these genes.

Egg Yolk Factor of Staphylococcus aureus II. Characterization of the Lipase Activity

PubMed Central

Shah, D. B.; Wilson, J. B.

1965-01-01

Shah, D. B. (University of Wisconsin, Madison), and J. B. Wilson. Egg yolk factor of Staphylococcus aureus. II. Characterization of the lipase activity. J. Bacteriol. 89:949–953. 1965.—The staphylococcal egg yolk factor was characterized as a lipase. The enzyme had an optimal pH of 7.8, but the optimal pH of stability was 7. Substrate specificity data showed that the relative rate of hydrolysis was lowest with triacetin as substrate, was maximal with tributyrin, and decreased as the chain length of the acyl moieties increased. The enzyme showed an absolute requirement for a fatty acid acceptor like calcium, when the acyl moiety of triglyceride was water-insoluble. Magnesium, strontium, and barium functioned equally well as fatty acid acceptors. The enzyme was able to hydrolyze coconut oil, peanut oil, olive oil, and egg yolk oil. PMID:14276120

Peptide reranking with protein-peptide correspondence and precursor peak intensity information.

PubMed

Yang, Chao; He, Zengyou; Yang, Can; Yu, Weichuan

2012-01-01

Searching tandem mass spectra against a protein database has been a mainstream method for peptide identification. Improving peptide identification results by ranking true Peptide-Spectrum Matches (PSMs) over their false counterparts leads to the development of various reranking algorithms. In peptide reranking, discriminative information is essential to distinguish true PSMs from false PSMs. Generally, most peptide reranking methods obtain discriminative information directly from database search scores or by training machine learning models. Information in the protein database and MS1 spectra (i.e., single stage MS spectra) is ignored. In this paper, we propose to use information in the protein database and MS1 spectra to rerank peptide identification results. To quantitatively analyze their effects to peptide reranking results, three peptide reranking methods are proposed: PPMRanker, PPIRanker, and MIRanker. PPMRanker only uses Protein-Peptide Map (PPM) information from the protein database, PPIRanker only uses Precursor Peak Intensity (PPI) information, and MIRanker employs both PPM information and PPI information. According to our experiments on a standard protein mixture data set, a human data set and a mouse data set, PPMRanker and MIRanker achieve better peptide reranking results than PetideProphet, PeptideProphet+NSP (number of sibling peptides) and a score regularization method SRPI. The source codes of PPMRanker, PPIRanker, and MIRanker, and all supplementary documents are available at our website: http://bioinformatics.ust.hk/pepreranking/. Alternatively, these documents can also be downloaded from: http://sourceforge.net/projects/pepreranking/.

Production and characterization of egg yolk antibody (IgY) against recombinant VP8-S2 antigen.

PubMed

Nasiri, K; Nassiri, M R; Tahmoorespur, M; Haghparast, A; Zibaee, S

2016-01-01

Bovine Rotavirus and Bovine Coronavirus are the most important causes of diarrhea in newborn calves and in some other species such as pigs and sheep. VP8 subunit of rotavirus is the major determinant of the viral infectivity and neutralization. Spike glycoprotein of coronavirus is responsible for induction of neutralizing antibody response. Studies showed that immunoglobulin of egg yolk (IgY) from immunized hens has been identified to be a convenient source for specific antibodies for using in immunotherapy and immunodiagnostic to limit the infections. In this study, chimeric VP8-S2 gene was designed using by computational techniques. The chimeric VP8-S2 gene was cloned and sub-cloned into pGH and pET32a (+) vectors. Then, recombinant pET32a-VP8-S2 vector was transferred into E. coli BL21 CodonPlus (DE3). The expressed protein was purified by Ni-NTA chromatography column. Hens were immunized with the purified VP8-S2 protein three times. IgY was purified from egg yolks using polyethylene glycol precipitation method. Activity and specificity of anti-VP8-S2 IgY were detected by dot-blotting, Western-blotting and indirect ELISA. We obtained anti-VP8-S2 IgY by immunizing hens with the recombinant VP8-S2 protein. The anti-VP8-S2 IgY was showed to bind specifically to the chimeric VP8-S2 protein by dot-blotting, Western-blotting analyses and indirect ELISA. The result of this study indicated that such construction can be useful to investigate as candidates for development of detection methods for simultaneous diagnosis of both infections. Specific IgY against the recombinant VP8-S2 could be recommended as a candidate for passive immunization against bovine rotavirus and bovine coronavirus.

A single amino acid difference between the intracellular domains of amyloid precursor protein and amyloid-like precursor protein 2 enables induction of synaptic depression and block of long-term potentiation.

PubMed

Trillaud-Doppia, Emilie; Paradis-Isler, Nicolas; Boehm, Jannic

2016-07-01

Alzheimer disease (AD) is initially characterized as a disease of the synapse that affects synaptic transmission and synaptic plasticity. While amyloid-beta and tau have been traditionally implicated in causing AD, recent studies suggest that other factors, such as the intracellular domain of the amyloid-precursor protein (APP-ICD), can also play a role in the development of AD. Here, we show that the expression of APP-ICD induces synaptic depression, while the intracellular domain of its homolog amyloid-like precursor protein 2 (APLP2-ICD) does not. We are able to show that this effect by APP-ICD is due to a single alanine vs. proline difference between APP-ICD and APLP2-ICD. The alanine in APP-ICD and the proline in APLP2-ICD lie directly behind a conserved caspase cleavage site. Inhibition of caspase cleavage of APP-ICD prevents the induction of synaptic depression. Finally, we show that the expression of APP-ICD increases and facilitates long-term depression and blocks induction of long-term potentiation. The block in long-term potentiation can be overcome by mutating the aforementioned alanine in APP-ICD to the proline of APLP2. Based on our results, we propose the emergence of a new APP critical domain for the regulation of synaptic plasticity and in consequence for the development of AD. Copyright © 2016 Elsevier Inc. All rights reserved.

Fishy Odor and TMA Content Levels in Duck Egg Yolks.

PubMed

Li, Xingzheng; Yuan, Gongjiao; Chen, Xia; Guo, Yuying; Yang, Ning; Pi, Jinsong; Zhang, Hao; Zheng, Jiangxia

2018-01-01

The differences between the trimethylamine (TMA) content levels in duck and chicken egg yolks under normal dietary conditions were compared. Moreover, the association between the polymorphisms of the duck FMO3 gene and TMA content levels in duck egg yolks was analyzed. Then, to detect the mutations associated with the fish-flavor trait, duck populations were selected for a high-choline diet experiment, which was followed by full-length sequencing of the FMO3 exons. The results showed that the TMA content levels in duck eggs (3.60 μg/g) were significantly higher than those in chicken eggs (2.35 μg/g) under normal dietary conditions (P < 0.01). With regard to the high-choline diet, the average TMA content levels in duck egg yolks (9.21 μg/g; P < 0.01) increased significantly. Furthermore, 5 SNPs reported in Ensembl database were detected in duck FMO3 exons. However, no mutation loci were found to be significantly associated with the TMA content levels in duck egg yolks. Besides, duck liver FMO3 mRNA expression levels were not associated with the TMA content levels. The results indicated that excessive TMA deposition in duck eggs is one of main factors causing the fishy odor in duck eggs, and the addition of choline in the ducks' diets was responsible for inducing an increase in the TMA content levels in duck eggs. Our study can help to diminish the fishy taste in duck eggs by reducing the amount of supplemented choline. Furthermore, this study laid a solid foundation for revealing the genetic factors involved in the fishy odor in duck eggs. © 2017 Institute of Food Technologists®.

Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens.

PubMed

Afrose, S; Hossain, M S; Tsujii, H

2010-12-01

1. The objective of the study was to investigate the effect of dietary karaya saponin on cholesterol deposition in laying hens. 2. A total of 40 Boris Brown hens were randomly assigned at 20 weeks of age to 4 treatment groups and fed on diets supplemented with 0 (control), 25, 50 or 75 mg/kg karaya saponin for an 8-week experimental period. 3. After 8 weeks of dietary supplementation, karaya-saponin-treated groups had significantly lower serum cholesterol (23·0%) and triglycerides but increased high density lipoproteins cholesterol concentration than controls, irrespective of karaya saponin content in the diet. Egg yolk cholesterol and triglycerides were also significantly reduced by dietary karaya saponin. Hepatic cholesterol and triglycerides were significantly reduced by karaya saponin but bile acids concentration in the faeces and liver were significantly increased by karaya saponin. The concentrations of oleic, linoleic and linolenic acids in the yolk were greater in hens receiving karaya saponin than in controls. Karaya saponin significantly increased egg production, feed efficiency and yolk colour compared with controls. Karaya saponin tended to increase egg weight, feed consumption, Haugh units, albumen weight and yolk index. 4. In conclusion, karaya saponin is a potential agent for reducing yolk cholesterol concentration together with an overall increase of production performance and improvement in egg quality.

Facile, general and template-free construction of monodisperse yolk-shell metal@carbon nanospheres.

PubMed

Xu, Fei; Lu, Yuheng; Ma, Junhao; Huang, Zhike; Su, Quanfei; Fu, Ruowen; Wu, Dingcai

2017-11-07

Herein, we report a general and template-free protocol to construct novel yolk-shell metal@carbon nanospheres based on confined interfacial copolymerization, which greatly simplifies the synthetic route, yields uniform nanospheres with controllable diameters, and results in highly porous carbon shells. The yolk-shell Au@carbon shows improved adsorption capacity and high catalytic ability due to the synergistic effect of Au and the porous carbon shell.

The Role of the Progressive Ankylosis Protein (ANK) in Adipogenic/Osteogenic Fate Decision of Precursor Cells

PubMed Central

Minashima, Takeshi; Quirno, Martin; Lee, You Jin; Kirsch, Thorsten

2017-01-01

The progressive ankylosis protein (ANK) is a transmembrane protein that transports intracellular pyrophosphate (PPi) to the extracellular milieu. In this study we show increased fatty degeneration of the bone marrow of adult ank/ank mice, which lack a functional ANK protein. In addition, isolated bone marrow stromal cells (BMSCs) isolated from ank/ank mice showed a decreased proliferation rate and osteogenic differentiation potential, and an increased adipogenic differentiation potential compared to BMSCs isolated from wild type (WT) littermates. Wnt signaling pathway PCR array analysis revealed that Wnt ligands, Wnt receptors and Wnt signaling proteins that stimulate osteoblast differentiation were expressed at markedly lower levels in ank/ank BMSCs than in WT BMSCs. Lack of ANK function also resulted in impaired bone fracture healing, as indicated by a smaller callus formed and delayed bone formation in the callus site. Whereas 5 weeks after fracture, the fractured bone in WT mice was further remodeled and restored to original shape, the fractured bone in ank/ank mice was not fully restored and remodeled to original shape. In conclusion, our study provides evidence that ANK plays a critical role in the adipogenic/osteogenic fate decision of adult mesenchymal precursor cells. ANK functions in precursor cells are required for osteogenic differentiation of these cells during adult bone homeostasis and repair, whereas lack of ANK functions favors adipogenic differentiation. PMID:28286238

Split2 Protein-Ligation Generates Active IL-6-Type Hyper-Cytokines from Inactive Precursors.

PubMed

Moll, Jens M; Wehmöller, Melanie; Frank, Nils C; Homey, Lisa; Baran, Paul; Garbers, Christoph; Lamertz, Larissa; Axelrod, Jonathan H; Galun, Eithan; Mootz, Henning D; Scheller, Jürgen

2017-12-15

Trans-signaling of the major pro- and anti-inflammatory cytokines Interleukin (IL)-6 and IL-11 has the unique feature to virtually activate all cells of the body and is critically involved in chronic inflammation and regeneration. Hyper-IL-6 and Hyper-IL-11 are single chain designer trans-signaling cytokines, in which the cytokine and soluble receptor units are trapped in one complex via a flexible peptide linker. Albeit, Hyper-cytokines are essential tools to study trans-signaling in vitro and in vivo, the superior potency of these designer cytokines are accompanied by undesirable stress responses. To enable tailor-made generation of Hyper-cytokines, we developed inactive split-cytokine-precursors adapted for posttranslational reassembly by split-intein mediated protein trans-splicing (PTS). We identified cutting sites within IL-6 (E 134 /S 135 ) and IL-11 (G 116 /S 117 ) and obtained inactive split-Hyper-IL-6 and split-Hyper-IL-11 cytokine precursors. After fusion with split-inteins, PTS resulted in reconstitution of active Hyper-cytokines, which were efficiently secreted from transfected cells. Our strategy comprises the development of a background-free cytokine signaling system from reversibly inactivated precursor cytokines.

Isolation of Cholesterol from an Egg Yolk

ERIC Educational Resources Information Center

Taber, Douglass F.; Li, Rui; Anson, Cory M.

2011-01-01

A simple procedure for the isolation of the cholesterol, by hydrolysis and extraction followed by column chromatography, is described. The cholesterol can be further purified by complexation with oxalic acid. It can also be oxidized and conjugated to cholestenone. The source of the cholesterol is one egg yolk, which contains about 200 mg of…

Improved fatty acid analysis of conjugated linoleic acid rich egg yolk triacylglycerols and phospholipid species.

PubMed

Shinn, Sara; Liyanage, Rohana; Lay, Jack; Proctor, Andrew

2014-07-16

Reports from chicken conjugated linoleic acid (CLA) feeding trials are limited to yolk total fatty acid composition, which consistently described increased saturated fatty acids and decreased monounsaturated fatty acids. However, information on CLA triacylglycerol (TAG) and phospholipid (PL) species is limited. This study determined the fatty acid composition of total lipids in CLA-rich egg yolk produced with CLA-rich soy oil, relative to control yolks using gas chromatography with flame ionization detection (GC-FID), determined TAG and PL fatty acid compositions by thin-layer chromatography-GC-FID (TLC-GC-FID), identified intact PL and TAG species by TLC-matrix-assisted laser desorption/ionization mass spectrometry (TLC-MALDI-MS), and determined the composition of TAG and PL species in CLA and control yolks by direct flow infusion electrospray ionization MS (DFI ESI-MS). In total, 2 lyso-phosphatidyl choline (LPC) species, 1 sphingomyelin species, 17 phosphatidyl choline species, 19 TAG species, and 9 phosphatidyl ethanolamine species were identified. Fifty percent of CLA was found in TAG, occurring predominantly in C52:5 and C52:4 TAG species. CLA-rich yolks contained significantly more LPC than did control eggs. Comprehensive lipid profiling may provide insight on relationships between lipid composition and the functional properties of CLA-rich eggs.

Synergetic Effect of Yolk-Shell Structure and Uniform Mixing of SnS-MoS₂ Nanocrystals for Improved Na-Ion Storage Capabilities.

PubMed

Choi, Seung Ho; Kang, Yun Chan

2015-11-11

Mixed metal sulfide composite microspheres with a yolk-shell structure for sodium-ion batteries are studied. Tin-molybdenum oxide yolk-shell microspheres prepared by a one-pot spray pyrolysis process transform into yolk-shell SnS-MoS2 composite microspheres. The discharge capacities of the yolk-shell and dense-structured SnS-MoS2 composite microspheres for the 100th cycle are 396 and 207 mA h g(-1), and their capacity retentions measured from the second cycle are 89 and 47%, respectively. The yolk-shell SnS-MoS2 composite microspheres with high structural stability during repeated sodium insertion and desertion processes have low charge-transfer resistance even after long-term cycling. The synergetic effect of the yolk-shell structure and uniform mixing of the SnS and MoS2 nanocrystals result in the excellent sodium-ion storage properties of the yolk-shell SnS-MoS2 composite microspheres by improving their structural stability during cycling.

Development of the inverted visceral yolk sac in three species of caviids (Rodentia, Caviomorpha, Caviidae).

PubMed

Miglino, M A; Franciolli, A L R; de Oliveira, M F; Ambrósio, C E; Bonatelli, M; Machado, M R F; Mess, A

2008-08-01

Guinea pig related rodents possess numerous derived placental characters. We attempt to identify diversity within the visceral yolk sac and its association with the chorioallantoic placenta in three species of caviids, two of them possessing a capsule formed by the decidua that covers the chorioallantoic placenta. The results verify that in early pregnancy all three species have an inverted yolk sac placenta. In advanced pregnancy the species differ: Galea spixii, as representative without a capsule, bear a yolk sac in apposition to the chorioallantoic placenta with signs of exchange activity until term. Galea is similar to other caviomorphs in this respect. In Dasyprocta leporina and Cuniculus paca, the representatives possessing a capsule, the yolk sac endoderm lacks signs of substance exchange. Evidently, the presence of a capsule prevents such an interaction. The variations established here must be considered if animal models for human placentation are required which have restricted access to the chorioallantoic placenta from the outside.

Incorporation of DNA and Protein Precursors into Macromolecules by Bacteria at −15oC

PubMed Central

Christner, Brent C.

2002-01-01

DNA and protein precursors were incorporated into trichloroacetic acid-precipitated material by bacterial cell suspensions during incubation for 50 to 100 days at −15oC. Incorporation did not occur at −70oC and was inhibited by antibiotics. The results demonstrate that bacteria can perform macromolecular synthesis under conditions that mimic entrapment in glacial ice. PMID:12450874

Design and Synthesis of Spherical Multicomponent Aggregates Composed of Core-Shell, Yolk-Shell, and Hollow Nanospheres and Their Lithium-Ion Storage Performances.

PubMed

Park, Gi Dae; Kang, Yun Chan

2018-03-01

Micrometer-sized spherical aggregates of Sn and Co components containing core-shell, yolk-shell, hollow nanospheres are synthesized by applying nanoscale Kirkendall diffusion in the large-scale spray drying process. The Sn 2 Co 3 -Co 3 SnC 0.7 -C composite microspheres uniformly dispersed with Sn 2 Co 3 -Co 3 SnC 0.7 mixed nanocrystals are formed by the first-step reduction of spray-dried precursor powders at 900 °C. The second-step oxidation process transforms the Sn 2 Co 3 -Co 3 SnC 0.7 -C composite into the porous microsphere composed of Sn-Sn 2 Co 3 @CoSnO 3 -Co 3 O 4 core-shell, Sn-Sn 2 Co 3 @CoSnO 3 -Co 3 O 4 yolk-shell, and CoSnO 3 -Co 3 O 4 hollow nanospheres at 300, 400, and 500 °C, respectively. The discharge capacity of the microspheres with Sn-Sn 2 Co 3 @CoSnO 3 -Co 3 O 4 core-shell, Sn-Sn 2 Co 3 @CoSnO 3 -Co 3 O 4 yolk-shell, and CoSnO 3 -Co 3 O 4 hollow nanospheres for the 200 th cycle at a current density of 1 A g -1 is 1265, 987, and 569 mA h g -1 , respectively. The ultrafine primary nanoparticles with a core-shell structure improve the structural stability of the porous-structured microspheres during repeated lithium insertion and desertion processes. The porous Sn-Sn 2 Co 3 @CoSnO 3 -Co 3 O 4 microspheres with core-shell primary nanoparticles show excellent cycling and rate performances as anode materials for lithium-ion batteries. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The nature of exocytosis in the yolk trophoblastic layer of silver arowana (Osteoglossum bicirrhosum) juvenile, the representative of ancient teleost fishes.

PubMed

Jaroszewska, Marta; Dabrowski, Konrad

2009-11-01

We have chosen the silver arowana (Osteoglossum bicirrhosum), a representative of the most ancient teleost family Osteoglossidae, to address the question of yolk nutrients utilization. Silver arowana have particularly large eggs (1-1.5 cm of diameter) and a unique morphology of the yolk. We present evidence that the yolk cytoplasmic zone (ycz) in the "yolksac juveniles" is a very complex structure involved in sequential processes of yolk hydrolysis, lipoprotein particles synthesis, their transport, and exocytosis. Vacuoles filled with yolk granules in different stages of digestion move from the vitellolysis zone through the ycz to be emptied into the microvillar interspace in the process of exocytosis. The area of the ycz with the abundance of the mitochondria must play an important role in providing energy for both the transport of vacuoles and the release of their contents. Therefore, we postulate that the function of yolk syncytial layer (ysl) as the "early embryonic patterning center" transforms in fish larvae or yolksac juveniles into a predominantly specialized role as the yolk trophoblastic layer (ytl) involved in yolk nutrients utilization. In addition to discovering the mechanism of transformation of the ysl function into ytl function, we suggest that the machinery involved in nutrient mobilization and exocytosis in yolk of arowana yolksac juveniles can be very attractive system for studies of regulatory processes in almost all secretory pathways in animal cells.

Amyloid precursor protein modulates ERK-1 and -2 signaling.

PubMed

Venezia, Valentina; Nizzari, Mario; Repetto, Emanuela; Violani, Elisabetta; Corsaro, Alessandro; Thellung, Stefano; Villa, Valentina; Carlo, Pia; Schettini, Gennaro; Florio, Tullio; Russo, Claudio

2006-12-01

The amyloid precursor protein (APP) is a transmembrane protein with a short cytoplasmic tail whose physiological function is unclear, although it is well documented that the proteolytic processing of APP could influence the development of Alzheimer's disease (AD) through the formation of membrane-bound C-terminal fragments (CTFs) and of beta-amyloid peptides (Abeta). We have recently shown that tyrosine-phosphorylated APP and CTFs may interact with Grb2 and ShcA adaptor proteins and that this coupling occurs at a higher extent in AD subjects only. To study the interaction between APP or CTFs and ShcA/Grb2 and to investigate their molecular target we have used as experimental model two different cell lines: H4 human neuroglioma cells and APP/APLP null mouse embryonic fibroblast cells (MEFs). Here we show that in H4 cells APP interacts with Grb2; conversely in APP/APLP-null MEF cells this interaction is possible only after the reintroduction of human APP by transfection. We have also shown that in MEF cells the transfection of a plasmid encoding for human APP wild-type enhances the phosphorylation of ERK-1 and -2 as revealed by Western blotting and immunofluorescence experiments. Finally, also in H4 cells the overexpression of APP upregulates the levels of phospho-ERK-1 and -2. In summary our data suggest that APP may influence phospho-ERK-1 and -2 signaling through its binding with Grb2 and ShcA adaptors. The meaning of this event is not clear, but APP interaction with these adaptors could be relevant to regulate mitogenic pathway.

Dietary (−)-epicatechin as a potent inhibitor of βγ-secretase amyloid precursor protein processing☆

PubMed Central

Cox, Carla J.; Choudhry, Fahd; Peacey, Eleanor; Perkinton, Michael S.; Richardson, Jill C.; Howlett, David R.; Lichtenthaler, Stefan F.; Francis, Paul T.; Williams, Robert J.

2015-01-01

Flavonoids, a group of dietary polyphenols have been shown to possess cognitive health benefits. Epidemiologic evidence suggests that they could play a role in risk reduction in dementia. Amyloid precursor protein processing and the subsequent generation of amyloid beta (Aβ) are central to the pathogenesis of Alzheimer's disease, as soluble, oligomeric Aβ is thought to be the toxic species driving disease progression. We undertook an in vitro screen to identify flavonoids with bioactivity at βγ-mediated amyloid precursor protein processing, which lead to identification of a number of flavonoids bioactive at 100 nM. Because of known bioavailability, we investigated the catechin family further and identified epigallocatechin and (−)-epicatechin as potent (nanomolar) inhibitors of amyloidogenic processing. Supporting this finding, we have shown reduced Aβ pathology and Aβ levels following short term, a 21-day oral delivery of (−)-epicatechin in 7-month-old TASTPM mice. Further, in vitro mechanistic studies suggest this is likely because of indirect BACE1 inhibition. Taken together, our results suggest that orally delivered (−)-epicatechin may be a potential prophylactic for Alzheimer's disease. PMID:25316600

Ethanol Gas Detection Using a Yolk-Shell (Core-Shell) α-Fe2O3 Nanospheres as Sensing Material.

PubMed

Wang, LiLi; Lou, Zheng; Deng, Jianan; Zhang, Rui; Zhang, Tong

2015-06-17

Three-dimensional (3D) nanostructures of α-Fe2O3 materials, including both hollow sphere-shaped and yolk-shell (core-shell)-shaped, have been successfully synthesized via an environmentally friendly hydrothermal approach. By expertly adjusting the reaction time, the solid, hollow, and yolk-shell shaped α-Fe2O3 can be selectively synthesized. Yolk-shell α-Fe2O3 nanospheres display outer diameters of 350 nm, and the interstitial hollow spaces layer is intimately sandwiched between the inner and outer shell of α-Fe2O3 nanostructures. The possible growth mechanism of the yolk-shell nanostructure is proposed. The results showed that the well-defined bilayer interface effectively enhanced the sensing performance of the α-Fe2O3 nanostructures (i.e., yolk-shell α-Fe2O3@α-Fe2O3), owing predominantly to the unique nanostructure, thus facilitated the transport rate and augmented the adsorption quantity of the target gas molecule under gas detection.

Vitellogenin Production by Fishmeal-Containing Diets in Male Tilapia (Oreochromis Mossambicus)

EPA Science Inventory

In a number of fish species, male plasma has been shown to contain substantial levels of l7~estradiol (E z) and in certain cases, vitellogenin (Vg), an Ez-induced precursor of egg yolk protein that is specific to females. The presence ofEz and Vg in males raises questions about ...

Neurodegeneration in Alzheimer disease: role of amyloid precursor protein and presenilin 1 intracellular signaling.

PubMed

Nizzari, Mario; Thellung, Stefano; Corsaro, Alessandro; Villa, Valentina; Pagano, Aldo; Porcile, Carola; Russo, Claudio; Florio, Tullio

2012-01-01

Alzheimer disease (AD) is a heterogeneous neurodegenerative disorder characterized by (1) progressive loss of synapses and neurons, (2) intracellular neurofibrillary tangles, composed of hyperphosphorylated Tau protein, and (3) amyloid plaques. Genetically, AD is linked to mutations in few proteins amyloid precursor protein (APP) and presenilin 1 and 2 (PS1 and PS2). The molecular mechanisms underlying neurodegeneration in AD as well as the physiological function of APP are not yet known. A recent theory has proposed that APP and PS1 modulate intracellular signals to induce cell-cycle abnormalities responsible for neuronal death and possibly amyloid deposition. This hypothesis is supported by the presence of a complex network of proteins, clearly involved in the regulation of signal transduction mechanisms that interact with both APP and PS1. In this review we discuss the significance of novel finding related to cell-signaling events modulated by APP and PS1 in the development of neurodegeneration.

Testing an egg yolk supplemented diet on boars to aid in sperm adaptation at 5°C.

PubMed

Casas, Isabel; Miller-Lux, Yvonne; Osborne, Betty; Bonet, Sergi; Althouse, Gary C

2015-01-01

In many species, extended semen can be stored at low temperatures to slow bacterial growth. However, boar semen performs poorly at temperatures below 15 °C and this poses unique challenges, as it is not easy to maintain a constant 15-19 °C during shipment. Some extenders have been formulated with egg yolk for storage at 5 °C but the addition of egg yolk is not applicable in the majority of commercial operations. The purpose of this study was to evaluate if boar dietary supplementation with powdered egg yolk imparts any protective effects on sperm quality when stored at 15 °C and 5 °C for up to 11 days in a conventional extender. Ten boars were fed a commercial diet with the addition of 0.11 Kg of powdered egg yolk for 10 weeks. Ejaculates collected on weeks 4, 6, 8, and 10 were processed for storage at both 15 °C and 5 °C and compared with ejaculates from boars fed a standard diet. Throughout an 11-day storage period, sperm quality was assessed including several motility and morphologic parameters and select plasma membrane properties (fluidity, integrity, and triacylglycerol content). Linear regression models were used to describe effects of treatment, storage day, week and temperature on all sperm parameters. Overall, there were minimal beneficial effects of egg yolk treatment on sperm quality parameters. Sperm from egg yolk supplemented boars did have a slower decline in viability and plasma membrane fluidity than that observed in the control sperm when stored at 5 °C (p < 0.001). Additionally, there was an increase in total morphologic abnormalities in sperm from egg yolk fed boars compared to controls at week 10 (p <  .001). In conclusion, the results of this study do not support a significant benefit to sperm quality or resistance to cold storage when feeding a 10-week dietary supplementation of 0.11 Kg powdered egg yolk to crossbred boars.

A multipurpose fusion tag derived from an unstructured and hyperacidic region of the amyloid precursor protein

PubMed Central

Sangawa, Takeshi; Tabata, Sanae; Suzuki, Kei; Saheki, Yasushi; Tanaka, Keiji; Takagi, Junichi

2013-01-01

Expression and purification of aggregation-prone and disulfide-containing proteins in Escherichia coli remains as a major hurdle for structural and functional analyses of high-value target proteins. Here, we present a novel gene-fusion strategy that greatly simplifies purification and refolding procedure at very low cost using a unique hyperacidic module derived from the human amyloid precursor protein. Fusion with this polypeptide (dubbed FATT for Flag-Acidic-Target Tag) results in near-complete soluble expression of variety of extracellular proteins, which can be directly refolded in the crude bacterial lysate and purified in one-step by anion exchange chromatography. Application of this system enabled preparation of functionally active extracellular enzymes and antibody fragments without the need for condition optimization. PMID:23526492

Multi-shelled ZnCo2O4 yolk-shell spheres for high-performance acetone gas sensor

NASA Astrophysics Data System (ADS)

Xiong, Ya; Zhu, Zongye; Ding, Degong; Lu, Wenbo; Xue, Qingzhong

2018-06-01

In the present study, multi-shelled ZnCo2O4 yolk-shell spheres have been successfully prepared by using carbonaceous microspheres as templates. It is found that the multi-shelled ZnCo2O4 yolk-shell spheres based sensor shows optimal sensing performances (response value of 38.2, response/recovery time of 19 s/71 s) toward 500 ppm acetone at 200 °C. In addition, this sensor exhibits a low detection limit of 0.5 ppm acetone (response value of 1.36) and a good selectivity toward hydrogen, methane, ethanol, ammonia and carbon dioxide. Furthermore, it is demonstrated that acetone gas response of multi-shelled ZnCo2O4 yolk-shell spheres is significantly better than that of ZnCo2O4 nanotubes and ZnCo2O4 nanosheets. High acetone response of the multi-shelled ZnCo2O4 yolk-shell spheres is attributed to the enhanced gas accessibility of the multi-shell morphology caused by the small crystalline size and high specific surface area while the short response/recovery time is mainly related to the rapid gas diffusion determined by the highly porous structure. Our work puts forward an exciting opportunity in designing various yolk-shelled structures for multipurpose applications.

Effects of essential oils on performance, egg quality, nutrient digestibility and yolk fatty acid profile in laying hens.

PubMed

Ding, Xuemei; Yu, Yang; Su, Zhuowei; Zhang, Keying

2017-06-01

The study was conducted to investigate the effect of essential oils on performance, egg quality, nutrient digestibility and yolk fatty acid profile in laying hens. A total of 960 Lohmann laying hens aged 53 weeks were enrolled, under 4 different treatment diets supplemented with 0, 50, 100 and 150 mg/kg essential oils (Enviva EO, Dupont Nutrition Biosciences ApS, Denmark), respectively. Each treatment was replicated 8 times with 30 birds each. Birds were fed dietary treatment diets for 12 weeks (54 to 65 weeks). For data recording and analysis, a 12-week period was divided into 3 periods of 4 weeks' duration each: period 1 (54 to 57 weeks), period 2 (58 to 61 weeks), and period 3 (62 to 65 weeks). For the diet supplemented with Enviva EO, hen-day egg production and the feed conversion ratio (FCR) were significantly improved ( P  < 0.05) at weeks 58 to 61, and the eggshell thickness was significantly increased ( P  < 0.05) at week 65. However, egg production, egg weight, feed intake, FCR and other egg quality parameters (albumen height, Haugh unit, egg yolk color and eggshell strength) were not affected by the dietary treatment. In addition, compared with the control diet, protein digestibility in the 100 mg/kg Enviva EO treatment group was significantly increased ( P  < 0.05), and fat digestibility in the 100 and 150 mg/kg Enviva EO treatment groups was significantly decreased ( P  < 0.05), but Enviva EO had no effect on energy apparent digestibility. Saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) gradually decreased and polyunsaturated fatty acid (PUFA) increased with Enviva EO supplementation, but the difference was not significant. The data suggested that the supplementation of essential oils (Enviva EO) in laying hen diet did not show a significant positive effect on performance and yolk fatty acid composition but it tended to increase eggshell thickness and protein digestibility, especially at the dose of 50 mg/kg.

Amyloid precursor protein and Presenilin1 interact with the adaptor GRB2 and modulate ERK 1,2 signaling.

PubMed

Nizzari, Mario; Venezia, Valentina; Repetto, Emanuela; Caorsi, Valentina; Magrassi, Raffaella; Gagliani, Maria Cristina; Carlo, Pia; Florio, Tullio; Schettini, Gennaro; Tacchetti, Carlo; Russo, Tommaso; Diaspro, Alberto; Russo, Claudio

2007-05-04

The amyloid precursor protein (APP) and the presenilins 1 and 2 are genetically linked to the development of familial Alzheimer disease. APP is a single-pass transmembrane protein and precursor of fibrillar and toxic amyloid-beta peptides, which are considered responsible for Alzheimer disease neurodegeneration. Presenilins are multipass membrane proteins, involved in the enzymatic cleavage of APP and other signaling receptors and transducers. The role of APP and presenilins in Alzheimer disease development seems to be related to the formation of amyloid-beta peptides; however, their physiological function, reciprocal interaction, and molecular mechanisms leading to neurodegeneration are unclear. APP and presenilins are also involved in multiple interactions with intracellular proteins, the significance of which is under investigation. Among the different APP-interacting proteins, we focused our interest on the GRB2 adaptor protein, which connects cell surface receptors to intracellular signaling pathways. In this study we provide evidence by co-immunoprecipitation experiments, confocal and electron microscopy, and by fluorescence resonance energy transfer experiments that both APP and presenilin1 interact with GRB2 in vesicular structures at the centrosome of the cell. The final target for these interactions is ERK1,2, which is activated in mitotic centrosomes in a PS1- and APP-dependent manner. These data suggest that both APP and presenilin1 can be part of a common signaling pathway that regulates ERK1,2 and the cell cycle.

Deposition of carotenoids in egg yolk by short-term supplement of coloured carrot (Daucus carota) varieties as forage material for egg-laying hens.

PubMed

Hammershøj, Marianne; Kidmose, Ulla; Steenfeldt, Sanna

2010-05-01

Supplying egg-laying hens with different forage materials may influence egg production and quality. The aim of this study was to examine the short-term effects of standard feed plus 70 g day(-1) per hen of three coloured carrot varieties (orange, yellow and purple) as forage material in comparison with a standard feed control on egg production, egg yolk colour and deposition of carotenoids in the yolk. Carrot supplementation reduced feed intakes significantly, but not on a dry matter basis. Orange carrot treatment significantly reduced egg mass production, whereas yellow and purple carrot treatments did not differ from the control. Egg and yolk weights of all carrot-supplemented treatments were significantly lower than those of the control, but yolk percentages were similar. Yolk redness increased significantly in the order control < yellow < orange < purple. A similar trend was seen for yolk yellowness, but yellow and orange carrots reached the same level. Yolk colour and carotenoid contents correlated positively and significantly. In particular, purple carrot treatment increased the yolk content of lutein (>1.5-fold) and beta-carotene (>100-fold) compared with the control. Supplementing the feed of egg-laying hens with coloured carrots efficiently increased yolk colour parameters and carotenoid contents, which gives opportunities for improved nutritional value of eggs from forage material-supplemented hens.

Serum and egg yolk antibody detection in chickens infected with low pathogenicity avian influenza virus.

PubMed

Sá e Silva, Mariana; Swayne, David E

2012-09-01

Surveillance for low pathogenicity avian influenza virus (LPAIV) infections has primarily relied on labor-intensive collection and serological testing of serum, but for many poultry diseases, easier-to-collect yolk samples have replaced serum for surveillance testing. A time-course LPAIV infection study in layers was performed to evaluate the utility of antibody detection in serum vs. egg yolk samples. Layers inoculated with the LPAIV A/Bobwhite Quail/Pennsylvania/20304/98 (H7N2) were tested for antibody levels in the serum and egg yolk by using the agar gel immunodiffusion test (AGID), hemagglutination-inhibition test (HI), and a commercially available enzyme-linked immunosorbent assay (ELISA). Anti-influenza specific antibodies were detected in the serum as early as 7 days postinoculation (DPI), and the majority of the hens remained positive until 42 DPI. Antibodies in the egg yolk were first detected by AGID at 7 DPI, which was also the first day of detection in serum. However, the majority of the eggs were positive by all techniques at 11 DPI and remained positive until 42 DPI, at which time the number of AGID+ and HI+ samples declined slightly as compared to ELISA+ samples. These results suggest that egg yolk can be an alternative to serum for flock serological surveillance against LPAIV infections, and the three methods (AGID, HI, and ELISA) will give similar results for first 42 days after infection, although AGID may give earlier positive response.

Preparation of yolk-shell MoS2 nanospheres covered with carbon shell for excellent lithium-ion battery anodes

NASA Astrophysics Data System (ADS)

Guo, Bangjun; Feng, Yu; Chen, Xiaofan; Li, Bo; Yu, Ke

2018-03-01

Molybdenum disulfide is regarded as one of the most promising electrode materials for high performance lithium-ion batteries. Designing firm basal structure is a key point to fully utilize the high capacity of layered MoS2 nanomaterials. Here, yolk-shell structured MoS2 nanospheres is firstly designed and fabricated to meet this needs. This unique yolk-shell nanospheres are transformed from solid nanospheres by a simply weak alkaline etching method. Then, the yolk-shell MoS2/C is synthesized by a facile process to protect the outside MoS2 shell and promote the conductivity. Taking advantages of high capacity and well-defined cavity space, allowing the core MoS2 to expand freely without breaking the outer shells, yolk-shell MoS2/C nanospheres delivers long cycle life (94% of capacity retained after 200 cycles) and high rate behaviour (830 mA h g-1 at 5 A g-1). This design of yolk-shell structure may set up a new strategy for preparing next generation anode materials for LIBs.

Trehalose Alters Subcellular Trafficking and the Metabolism of the Alzheimer-associated Amyloid Precursor Protein*

PubMed Central

Tien, Nguyen T.; Karaca, Ilker; Tamboli, Irfan Y.

2016-01-01

The disaccharide trehalose is commonly considered to stimulate autophagy. Cell treatment with trehalose could decrease cytosolic aggregates of potentially pathogenic proteins, including mutant huntingtin, α-synuclein, and phosphorylated tau that are associated with neurodegenerative diseases. Here, we demonstrate that trehalose also alters the metabolism of the Alzheimer disease-related amyloid precursor protein (APP). Cell treatment with trehalose decreased the degradation of full-length APP and its C-terminal fragments. Trehalose also reduced the secretion of the amyloid-β peptide. Biochemical and cell biological experiments revealed that trehalose alters the subcellular distribution and decreases the degradation of APP C-terminal fragments in endolysosomal compartments. Trehalose also led to strong accumulation of the autophagic marker proteins LC3-II and p62, and decreased the proteolytic activation of the lysosomal hydrolase cathepsin D. The combined data indicate that trehalose decreases the lysosomal metabolism of APP by altering its endocytic vesicular transport. PMID:26957541

Effect of meiotic maturation on yolk platelet lipids from Bufo arenarum oocytes.

PubMed

Buschiazzo, Jorgelina; Alonso, Telma Susana

2005-09-01

Progesterone induces the resumption of meiosis in Bufo arenarum full-grown arrested oocytes through a nongenomic mechanism called meiotic maturation. Growing evidence indicates that lipids are involved in the maturation process. They are mainly located in yolk platelets, the principal organelles of amphibian oocytes. The aim of the present study was to analyze the effect of progesterone-induced maturation on lipids from B. arenarum yolk platelets. Ovarian oocytes, manually obtained, were incubated with progesterone to induce maturation. Yolk platelets were isolated by centrifugation at low velocity. Lipids were separated by thin-layer chromatography. For compositional analysis, they were derivatized by methanolysis, and were identified and quantified in a gas-liquid chromatograph. Phospholipid content decreased in progesterone-treated oocytes, mainly as a result of a decrease at the level of phosphatidylcholine (PC). The turnover of this lipid is considered crucial for the completion of meiosis. Sphingomyelin also underwent a decrease that could be related to the important role of ceramide as an inducer of germinal vesicle breakdown. Maturation effect on fatty acid composition registered significant changes in PC whose saturated fatty acids increased. A net increase in arachidonic acid was observed in phosphatidylserine after progesterone treatment. The contents of total triacylglycerols and diacylglycerols were not significantly modified by hormone effect while free fatty acids underwent a significant increase as a result of polyunsaturated fatty acids increase. Altogether, our results demonstrate that yolk platelet lipids are involved in the resumption of the meiotic cell cycle, thus suggesting that these organelles participate in a dynamic role during amphibian development. (c) 2005 Wiley-Liss, Inc.

Relationships between yolk androgens and nest density, laying date, and laying order in Western Burrowing Owls (Athene cunicularia hypugaea)

USGS Publications Warehouse

Welty, J.L.; Belthoff, J.R.; Egbert, J.; Schwabl, H.

2012-01-01

Increases in yolk androgens within and among avian clutches have been correlated with decreased incubation time, increased aggression within a nest, increased begging behaviour, decreased immune response, and decreased life span. Although the mechanisms that lead to variability in yolk androgens within and between clutches are not completely known, yolk androgens can be a function of both social and environmental conditions. We were interested in if and how nesting density, laying date, and laying order influenced yolk androgens in Western Burrowing Owls (Athene cunicularia hypugaea (Bonaparte, 1825)) in which nest density varies considerably. In 2006 and 2007, we used radioimmunoassay to quantify the concentrations of testosterone, 5a-dihydrotestosterone, and androstenedione in the egg yolks from one early and one latelaid egg in 47 nests of Burrowing Owls located in the Morley Nelson Snake River Birds of Prey National Conservation Area in southern Idaho. Nesting density had no detectable effect on yolk androgens. Yolk androgens varied temporally and peaked in the middle of the laying season while being low before and after this time period. Within nests, late-laid eggs had higher testosterone and dihydrotestosterone than early-laid eggs; adrostendione exhibited a similar pattern in one but not both years of our study. It is possible that the seasonal pattern in yolk androgens that we observed is related to aspects of mate quality for females or declining chances of fledging success for later nesting females, whereas rises in egg androgens between early and late eggs within clutches could reflect a mechanism to assist nestlings from late-laid eggs that hatch one to several days after their siblings to better compete for resources within the nest or promote survival in the presence of larger siblings.

Yolk-platelet crystals in three ancient bony fishes: Polypterus bichir (Polypteri), Amia calva L., and Lepisosteus osseus (L.) (Holostei).

PubMed

Lange, R H; Grodziński, Z; Kilarski, W

1982-01-01

Yolk-platelet crystals in Amia calva L., Lepisosteus osseus (L.) and Polypterus bichir have orthorhombic features with unit-cell dimensions a = 8.3 ... 8.8 nm, b = 16.4 ... 16.9 nm and c = 18.6 ... 19.8 nm as determined in electron-diffracted patterns of fixed, epoxy-resin embedded and thin-sectioned material. Electron-diffraction patterns, crystal projections and the above unit-cell data make them extremely similar to the orthorhombic yolk-platelet crystals known for amphibians and teleosts. This observation fills a gap in yolk-platelet research and supports the view that the general architecture of yolk platelets has been conserved for nearly 400 million years. It follows that the peculiar platelet architecture itself has physiological significance.

In vitro comparison of egg yolk-based and soybean lecithin-based extenders for cryopreservation of ram semen.

PubMed

Forouzanfar, M; Sharafi, M; Hosseini, S M; Ostadhosseini, S; Hajian, M; Hosseini, L; Abedi, P; Nili, N; Rahmani, H R; Nasr-Esfahani, M H

2010-03-01

Substitution of egg yolk with soybean lecithin may reduce hygienic risks in extenders. Though a few studies have been performed on the effect of soybean lecithin in bull, to date evaluation of ram semen in vitro fertility after cryopreservation with use of soybean lecithin has not been studied. This study assessed the effect of 1% or 2% (wt/vol) soybean lecithin (L1 or L2) or 15% or 20% (vol/vol) egg yolk (E15 or E20) supplemented with 5% or 7% glycerol (G5 or G7) in a Tris-based medium for cryopreservation of ram (Oviss arries) semen. Although no significant difference was observed in pattern of capacitation, the best results in terms of sperm motility, viability postthaw, and cleavage rates were observed with L1G7 (51.9+/-4.8%, 48.1+/-3.5%, and 79.6+/-3.9%, respectively) and E20G7 (51.8+/-2.9%, 46.7+/-4.0%, and 72.9+/-6.4%, respectively). Our results also showed that 1% lecithin and 20% egg yolk was superior to 2% lecithin and 15% egg yolk. In terms of cleavage rate, 7% glycerol was superior to 5% glycerol. No significant difference was obtained between groups in terms of blastocysts rate per cleaved embryo. Therefore, we concluded that the optimal concentration of lecithin and egg yolk is 1% and 20%, respectively, along with 7% glycerol. In addition, our results suggest that lecithin can be used as a substitute for egg yolk. Copyright 2010 Elsevier Inc. All rights reserved.

[Specific odor component produced by Mycobacterium lepraemurium on Ogawa yolk medium].

PubMed

Mori, T; Aishima, T

1992-11-01

When Mycobacterium lepraemurium is grown on the 1% Ogawa yolk medium, it produces a specific odor. This odor was not observed in other easily cultivable acid-fast bacilli. Therefore, identification of the components responsible for the specific odor produced by M. lepraemurium was attempted. The odor components were extracted for overnight with sterilized and distilled water from the Ogawa yolk medium on which M. lepraemurium had been cultivated for two months. The odor components in the extract was adsorbed on refined charcoal. After washing with distilled water for three times, the charcoal was dried. Then the odor components were eluted from the charcoal with ethanol and the eluate was condensed under nitrogen gas flow at 40 degrees C. The condensate was analyzed by Gas-Chromatography-Mass-Spectrum (GC-MS). Phenylethanol and phenylacetic acid were identified as major odor components. A mixture of authentic phenylacetic acid, its methyl and ethyl esters, smelled similar to the odor of cultivated medium of M. lepraemurium. Thus, phenylacetic acid was identified as the key odor component produced by M. lepraemurium. When initial isolation culture of M. lepraemurium from murine leproma was cultivated on the Ogawa yolk medium by adding phenylacetic acid, growth inhibition was brought by the compound.

Liposome encapsulated soy lecithin and cholesterol can efficiently replace chicken egg yolk in human semen cryopreservation medium.

PubMed

Mutalik, Srinivas; Salian, Sujith Raj; Avadhani, Kiran; Menon, Jyothsna; Joshi, Haritima; Hegde, Aswathi Raju; Kumar, Pratap; Kalthur, Guruprasad; Adiga, Satish Kumar

2014-06-01

Cryopreservation of spermatozoa plays a significant role in reproductive medicine and fertility preservation. Chicken egg yolk is used as an extender in cryopreservation of human spermatozoa using glycerol egg yolk citrate (GEYC) buffered medium. Even though 50% survival of spermatozoa is generally achieved with this method, the risk of high levels of endotoxins and transmission pathogens from chicken egg yolk is a matter of concern. In the present study we attempted to establish a chemically defined cryopreservation medium which can replace the chicken egg yolk without affecting sperm survival. Ejaculates from 28 men were cryopreserved with GEYC based freezing medium or liposome encapsulated soy lecithin-cholesterol based freezing medium (LFM). The semen samples were subjected to rapid thawing after 14 days of storage in liquid nitrogen. Post-thaw analysis indicated significantly higher post-thaw motility and sperm survival in spermatozoa cryopreserved with LFM compared to conventional GEYC freezing medium. The soy lecithin and cholesterol at the ratio of 80:20 with sucrose showed the highest percentage of post-thaw motility and survival compared to the other compositions. In conclusion, chemically defined cryopreservation medium with liposome encapsulated soy lecithin and cholesterol can effectively replace the chicken egg yolk from human semen cryopreservation medium without compromising post-thaw outcome.

Au@TiO2 yolk-shell nanostructures for enhanced performance in both photoelectric and photocatalytic solar conversion

NASA Astrophysics Data System (ADS)

He, Qinrong; Sun, Hang; Shang, Yinxing; Tang, Yanan; She, Ping; Zeng, Shan; Xu, Kongliang; Lu, Guolong; Liang, Song; Yin, Shengyan; Liu, Zhenning

2018-05-01

Solar energy conversion is an important field gaining increasing interest. Herein, bio-inspired Au@TiO2 yolk-shell nanoparticles (NPs) have been prepared via a facial one-pot hydrothermal approach. The Au@TiO2 yolk-shell NPs can self-assemble into 3D-structure to form photoelectrode for photoelectric conversion. The obtained photoelectrode demonstrates a swift and stable photocurrent of 3.5 μA/cm2, which is 4.2 and 1.6 times higher than those of the photocurrents generated by the counterparts of commercial TiO2 and Au@TiO2 core-shell NPs, respectively. Moreover, compared to the commercial TiO2 and Au@TiO2 core-shell NPs, the Au@TiO2 yolk-shell NPs also exhibit superior photocatalytic activity, delivering a H2 evolution rate of 4.92 mmol/g h. The performance improvement observed for the Au@TiO2 yolk-shell NPs is likely contributed by two synergistic factors, i.e. the incorporation of AuNPs and the unique hollow structure, which benefit the activity by simultaneously enhancing light utilization, charge separation and reaction site accessibility. The rational design and fabrication of Au@TiO2 yolk-shell NPs hold great promise for future application in efficient solar energy conversion.

Characterization of calcium carbonate crystals in pigeon yolk sacs with different incubation times.

PubMed

Song, Juan; Cheng, Haixia; Shen, Xinyu; Hu, Jingxiao; Tong, Hua

2014-05-01

Calcium carbonate crystals are known to form in the yolk sacs of fertile pigeon eggs at late stages of incubation. The composition and structure of these crystals were investigated, the crystallization environment was inspected, and the physical chemistry constants of the yolk fluid were determined through the incubation period. Polarized light microscopy was used to observe the generation and distribution of calcium carbonate crystals in the yolk sac. In addition, X-ray diffraction was employed to analyze the composition and crystal phase of the yolk sac. A decalcification and deproteination method was established to analyze the ultrastructure and composition of the crystals, as well as the internal relationship between inorganic and organic phases of the crystals. Additionally, scanning electron microscopy, transmission electron microscopy, X-ray energy dispersive spectroscopy, and Fourier transform infrared spectroscopy were used to evaluate the characteristics of the crystals. Our results demonstrated that the calcium carbonate crystals were mainly composed of vaterite and calcite, with vaterite being the major component. Vaterite, a type of biomaterial generated by an organic template control, presented as a concentric hierarchical spherical structure. The organic nature of the biomaterial prevented vaterite from transforming into calcite, which is more thermodynamically stable than vaterite. Additionally, the configuration, size, and aggregation of vaterite were also mediated by the organic template. This bio-vaterite was found during the incubation period and is valuable in calcium transport during embryonic development. Copyright © 2014 Elsevier Ltd. All rights reserved.

Quercetin prevents protein nitration and glycolytic block of proliferation in hydrogen peroxide insulted cultured neuronal precursor cells (NPCs): Implications on CNS regeneration.

PubMed

Sajad, Mir; Zargan, Jamil; Zargar, Mohammad Afzal; Sharma, Jyoti; Umar, Sadiq; Arora, Rajesh; Khan, Haider A

2013-05-01

Survival along with optimal proliferation of neuronal precursors determines the outcomes of the endogenous cellular repair in CNS. Cellular-oxidation based cell death has been described in several neurodegenerative disorders. Therefore, this study was aimed at the identification of the potent targets of oxidative damage to the neuronal precursors and its effective prevention by a natural flavonoid, Quercetin. Neuronal precursor cells (NPCs), Nestin+ and GFAP (Glial fibrillary acidic protein)+ were isolated and cultured from adult rat SVZ (subventricular zone). These cells were challenged with a single dose of H2O2 (50μM) and/or pre-treated with different concentrations of Quercetin. H2O2 severely limited the cellular viability and expansion of the neurospheres. Cellular-oxidation studies revealed reduction in glutathione dependent redox buffering along with depletion of enzymatic cellular antioxidants that might potentiate the nitrite (NO2(-)) and superoxide anion (O2(-)) mediated peroxynitrite (ONOO(-)) formation and irreversible protein nitration. We identified depleted PK-M2 (M2 isoform of pyruvate kinase) activity and apoptosis of NPCs revealed by the genomic DNA fragmentation and elevated PARP (poly ADP ribose polymerase) activity along with increased Caspase activity initiated by severely depolarised mitochondrial membranes. However, the pre-treatment of Quercetin in a dose-response manner prevented these changes and restored the expansion of neurospheres preferably by neutralizing the oxidative conditions and thereby reducing peroxynitrite formation, protein nitration and PK-M2 depletion. Our results unravel the potential interactions of oxidative environment and respiration in the survival and activation of precursors and offer a promise shown by a natural flavonoid in the protective strategy for neuronal precursors of adult brain. Copyright © 2013 Elsevier Inc. All rights reserved.

Promising Loci and Genes for Yolk and Ovary Weight in Chickens Revealed by a Genome-Wide Association Study.

PubMed

Sun, Congjiao; Lu, Jian; Yi, Guoqiang; Yuan, Jingwei; Duan, Zhongyi; Qu, Lujiang; Xu, Guiyun; Wang, Kehua; Yang, Ning

2015-01-01

Because it serves as the cytoplasm of the oocyte and provides a large amount of reserves, the egg yolk has biological significance for developing embryos. The ovary and its hierarchy of follicles are the main reproductive organs responsible for yolk deposition in chickens. However, the genetic architecture underlying the yolk and ovarian follicle weights remains elusive. Here, we measured the yolk weight (YW) at 11 age points from onset of egg laying to 72 weeks of age and measured the follicle weight (FW) and ovary weight (OW) at 73 weeks as part of a comprehensive genome-wide association study (GWAS) in 1,534 F2 hens derived from reciprocal crosses between White Leghorn (WL) and Dongxiang chickens (DX). For all ages, YWs exhibited moderate single nucleotide polymorphism (SNP)-based heritability estimates (0.25-0.38), while the estimates for FW (0.16) and OW (0.20) were relatively low. Independent univariate genome-wide screens for each trait identified 12, 3, and 31 novel significant associations with YW, FW, and OW, respectively. A list of candidate genes such as ZAR1, STARD13, ACER1b, ACSBG2, and DHRS12 were identified for having a plausible function in yolk and follicle development. These genes are important to the initiation of embryogenesis, lipid transport, lipoprotein synthesis, lipid droplet promotion, and steroid hormone metabolism, respectively. Our study provides for the first time a genome-wide association (GWA) analysis for follicle and ovary weight. Identification of the promising loci as well as potential candidate genes will greatly advance our understanding of the genetic basis underlying dynamic yolk weight and ovarian follicle development and has practical significance in breeding programs for the alteration of yolk weight at different age points.

Trehalose Alters Subcellular Trafficking and the Metabolism of the Alzheimer-associated Amyloid Precursor Protein.

PubMed

Tien, Nguyen T; Karaca, Ilker; Tamboli, Irfan Y; Walter, Jochen

2016-05-13

The disaccharide trehalose is commonly considered to stimulate autophagy. Cell treatment with trehalose could decrease cytosolic aggregates of potentially pathogenic proteins, including mutant huntingtin, α-synuclein, and phosphorylated tau that are associated with neurodegenerative diseases. Here, we demonstrate that trehalose also alters the metabolism of the Alzheimer disease-related amyloid precursor protein (APP). Cell treatment with trehalose decreased the degradation of full-length APP and its C-terminal fragments. Trehalose also reduced the secretion of the amyloid-β peptide. Biochemical and cell biological experiments revealed that trehalose alters the subcellular distribution and decreases the degradation of APP C-terminal fragments in endolysosomal compartments. Trehalose also led to strong accumulation of the autophagic marker proteins LC3-II and p62, and decreased the proteolytic activation of the lysosomal hydrolase cathepsin D. The combined data indicate that trehalose decreases the lysosomal metabolism of APP by altering its endocytic vesicular transport. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Biofortified orange maize enhances β-cryptoxanthin concentrations in egg yolks of laying hens better than tangerine peel fortificant.

PubMed

Heying, Emily K; Tanumihardjo, Jacob P; Vasic, Vedran; Cook, Mark; Palacios-Rojas, Natalia; Tanumihardjo, Sherry A

2014-12-10

The xanthophyll β-cryptoxanthin provides vitamin A and has other purported health benefits. Laying hens deposit xanthophyll carotenoids into egg yolk. Hens (n = 8/group) were fed conventional-bred high β-cryptoxanthin biofortified (orange) maize, tangerine peel-fortified white maize, lutein-fortified yellow maize, or white maize for 40 d to investigate yolk color changes using L*a*b* scales, yolk carotenoid enhancement, and hen vitamin A status. Yolks from hens fed orange maize had scores indicating a darker, orange color and mean higher β-cryptoxanthin, zeaxanthin, and β-carotene concentrations (8.43 ± 1.82, 23.1 ± 4.8, 0.16 ± 0.08 nmol/g, respectively) than other treatments (P < 0.0001). Yolk retinol concentrations (mean: 14.4 ± 3.42 nmol/g) were similar among groups and decreased with time (P < 0.0001). Hens fed orange maize had higher liver retinol (0.53 ± 0.20 μmol/g liver) than other groups (P < 0.0001). β-Cryptoxanthin-biofortified eggs could be another choice for consumers, providing enhanced color through a provitamin A carotenoid and supporting eggs' status as a functional food.

A simple and efficient method for preparing partially purified phosvitin from egg yolk using ethanol and salts.

PubMed

Ko, K Y; Nam, K C; Jo, C; Lee, E J; Ahn, D U

2011-05-01

The objective of this study was to develop a new protocol that could be used for large-scale separation of phosvitin from egg yolk using ethanol and salts. Yolk granules, which contain phosvitin, were precipitated after diluting egg yolk with 9 volumes of distilled water. The pH of the yolk solution was adjusted to pH 4.0 to 8.0 using 6 N HCl or NaOH, and then yolk granules containing phosvitin was separated by centrifugation at 3,220 × g for 30 min. Lipids and phospholipids were removed from the insoluble yolk granules using 85% ethanol. The optimal volumes and concentration of ethanol in removing lipids from the precipitants were determined. After centrifugation, the lipid-free precipitants were homogenized with 9 volumes of ammonium sulfate [(NH(4))(2)SO(4)] or NaCl to extract phosvitin. The optimal pH and concentration of (NH(4))(2)SO(4) or NaCl for the highest recovery rate and purity for phosvitin in final solution were determined. At pH 6.0, all the phosvitin in diluted egg yolk solution was precipitated. Among the (NH(4))(2)SO(4) and NaCl conditions tested, 10% (NH(4))(2)SO(4) or 10% NaCl at pH 4.0 yielded the greatest phosvitin extraction from the lipid-free precipitants. The recovery rates of phosvitin using (NH(4))(2)SO(4) and NaCl were 72 and 97%, respectively, and their purity was approximately 85%. Salt was removed from the extract using ultrafiltration. The salt-free phosvitin solution was concentrated using ultrafiltration, the impurities were removed by centrifugation, and the resulting solution was freeze-dried. The partially purified phosvitin was suitable for human use because ethanol was the only solvent used to remove lipids, (NH(4))(2)SO(4) or NaCl was used to extract phosvitin, and ultrafiltration was used to remove salt and concentrate the extract. The developed method was simple and suitable for a large-scale preparation of partially purified phosvitin.

Cholesterol-lowering activity of plant sterol-egg yolk lipoprotein complex in rats.

PubMed

Matsuoka, Ryosuke; Muto, Ayano; Kimura, Mamoru; Hoshina, Ryosuke; Wakamatsu, Toshio; Masuda, Yasunobu

2008-01-01

Free plant sterols cannot be dissolved in oil or water. Using free plant sterols and egg yolks, we developed a plant sterol-egg yolk lipoprotein complex (PSY) that can be dispersed in water and considered suitable for use in processed foods. The cholesterol-lowering activity of PSY was equal to that of free plant sterols and plant sterol esters. Consumption of a freeze-dried PSY-containing omelet reduced serum and hepatic cholesterol concentrations. The results suggest that PSY has cholesterol-lowering activity equivalent to that of free plant sterols and plant sterol esters. Moreover, the cholesterol-lowering activity of PSY was maintained in processed foods.

Chemical Compositions of Egg Yolks and Egg Quality of Laying Hens Fed Prebiotic, Probiotic, and Synbiotic Diets.

PubMed

Tang, Shirley Gee Hoon; Sieo, Chin Chin; Kalavathy, Ramasamy; Saad, Wan Zuhainis; Yong, Su Ting; Wong, Hee Kum; Ho, Yin Wan

2015-08-01

A 16-wk feeding experiment was conducted to investigate the effects of a prebiotic, isomaltooligosaccharide (IMO), a probiotic, PrimaLac®, and their combination as a synbiotic on the chemical compositions of egg yolks and the egg quality of laying hens. One hundred and sixty 16-wk-old Hisex Brown pullets were randomly assigned to 4 dietary treatments: (i) basal diet (control), (ii) basal diet + 1% IMO (PRE), (iii) basal diet + 0.1% PrimaLac® (PRO), and (iv) basal diet + 1% IMO + 0.1% PrimaLac® (SYN). PRE, PRO, or SYN supplementation not only significantly (P < 0.05) decreased the egg yolk cholesterol (24- and 28-wk-old) and total saturated fatty acids (SFA; 28-, 32-, and 36-wk-old), but also significantly (P < 0.05) increased total unsaturated fatty acids (UFA; 28-, 32-, and 36-wk-old), total omega 6 and polyunsaturated fatty acids (PUFA), including linoleic and alpha-linolenic acid levels in the eggs (28-wk-old). However, the total lipids, carotenoids, and tocopherols in the egg yolks were similar among all dietary treatments in the 24-, 28-, 32-, and 36-wk-old hens. Egg quality (Haugh unit, relative weights of the albumen and yolk, specific gravity, shell thickness, and yolk color) was not affected by PRE, PRO, or SYN supplementation. The results indicate that supplementations with IMO and PrimaLac® alone or in combination as a synbiotic might be useful for improving the cholesterol content and modifying the fatty acid compositions of egg yolk without affecting the quality of eggs from laying hens between 24 and 36 wk of age. © 2015 Institute of Food Technologists®

Effects of acetylate hyperforin on the processing of amyloid precursor protein

PubMed Central

Chen, Xiang; Feng, Wenshang; Chen, Qing; Yang, Xiangling; Yang, Depo; Wang, Dongmei; Zhong, Ling

2009-01-01

Hyperforin (HF) is a phloroglucinol compound obtained from St. John's Wort (Hypericum perforatum). Recent studies have shown that Hyperforin can be used to improve psychopathologic symptoms of Alzheimer's disease but the mechanism is not clear. This may be partly due to the difficult in studying Hyperforin, since this chemical is unstable and is sensitive to light, oxygen, and heat. In this study, we explored the effects of acetylate hyperforin (ace-HF), a stable derivative of hyperforin, on the processing of amyloid precursor protein (APP). HEK293 cells transfected with pcDNA3.1APP695sw and SH-SY5Y cells were treated with ace-HF, followed by measuring the levels of APP and sAPPα. Twelve hours of treatment led to an increase in extracellular sAPPα, but APP mRNA and protein levels were unchanged. Further studies with α-secretase and a pan PKC inhibitor, Calphostin C, indicated that ace-HF's effect on extracellular sAPPα was closely related to PKC activities and α-secretase activities. Our findings suggest that ace-HF can modulate α-secretase-mediated APP processing via a PKC signaling pathway. PMID:21383880

Effects of acetylate hyperforin on the processing of amyloid precursor protein.

PubMed

Chen, Xiang; Feng, Wenshang; Chen, Qing; Yang, Xiangling; Yang, Depo; Wang, Dongmei; Zhong, Ling

2009-02-20

Hyperforin (HF) is a phloroglucinol compound obtained from St. John's Wort (Hypericum perforatum). Recent studies have shown that Hyperforin can be used to improve psychopathologic symptoms of Alzheimer's disease but the mechanism is not clear. This may be partly due to the difficult in studying Hyperforin, since this chemical is unstable and is sensitive to light, oxygen, and heat. In this study, we explored the effects of acetylate hyperforin (ace-HF), a stable derivative of hyperforin, on the processing of amyloid precursor protein (APP). HEK293 cells transfected with pcDNA3.1APP695sw and SH-SY5Y cells were treated with ace-HF, followed by measuring the levels of APP and sAPPα. Twelve hours of treatment led to an increase in extracellular sAPPα, but APP mRNA and protein levels were unchanged. Further studies with α-secretase and a pan PKC inhibitor, Calphostin C, indicated that ace-HF's effect on extracellular sAPPα was closely related to PKC activities and α-secretase activities. Our findings suggest that ace-HF can modulate α-secretase-mediated APP processing via a PKC signaling pathway.

Cu₂O template synthesis of high-performance PtCu alloy yolk-shell cube catalysts for direct methanol fuel cells.

PubMed

Ye, Sheng-Hua; He, Xu-Jun; Ding, Liang-Xin; Pan, Zheng-Wei; Tong, Ye-Xiang; Wu, Mingmei; Li, Gao-Ren

2014-10-21

Novel PtCu alloy yolk-shell cubes were fabricated via the disproportionation and displacement reactions in Cu2O yolk-shell cubes, and they exhibit significantly improved catalytic activity and durability for methanol electrooxidation.

The effect of polyunsaturated fatty acids on the homeostasis of yolk lipoprotein in C. elegans examined by CARS and two-photon excitation fluorescence (TPE-F) microscopy

NASA Astrophysics Data System (ADS)

Chen, Wei-Wen; Yi, Yung-Hsiang; Chien, Cheng-Hao; Hsiung, Kuei-Ching; Lin, Yi-Chun; Ma, Tian-Hsiang; Lo, Szecheng J.; Chang, Ta-Chau

2016-03-01

Yolk lipoprotein constitutes the major source of energy and the materials for synthesizing signaling factors for the development of oocytes and embryos in C. elegans. Polyunsaturated fatty acids (PUFAs) packed in yolk lipoprotein have been recently recognized as critical molecules for fertilization and reproduction.1 However, the relation between PUFAs and the homeostasis of yolk lipoprotein is not clear. Here we use coherent anti-Stokes Raman scattering (CARS) microscopy and two-photon excitation fluorescence (TPE-F) microscopy to examine the transportation of yolk lipoprotein. We demonstrate that CARS microscopy is a more sensitive method than the traditional Nile Red staining method in probing the abnormal accumulation of yolk lipoprotein in the body cavity of C. elegans. It is found that the accumulation of yolk lipoprotein is a time-dependent process. In addition, a negative correlation (r = -0.955) between reproductive aging and abnormal accumulation of yolk lipoprotein is established. We further examine wild-type, fat-1, and fat-2 worms with or without the expression of GFP-tagged yolk lipoprotein (VIT-2-GFP). Our data reveal that PUFAs have a positive effect on the synthesis and endocytosis of yolk lipoprotein, confirming the model proposed by Edmonds et al.2

Dietary choline and phospholipid supplementation enhanced docosahexaenoic acid enrichment in egg yolk of laying hens fed a 2% Schizochytrium powder-added diet.

PubMed

Wang, H; Zhang, H J; Wang, X C; Wu, S G; Wang, J; Xu, L; Qi, G H

2017-08-01

The aim of this study was to evaluate the effect of dietary phospholipid supplementation on laying hen performance, egg quality, and the fatty acid profile of egg yolks from hens fed a 2% Schizochytrium powder diet. Three-hundred-sixty 28-wk-old Hy-line W-36 laying hens were randomly allocated to one of the 5 dietary treatments, each treatment with 6 replicates of 12 birds each. All diets included 2% Schizochytrium powder (docosahexaenoic acid [DHA], 137.09 mg/g). The control group was not supplemented with any additional phospholipids, whereas the other 4 experimental diets were supplemented with 1,000 mg/kg choline (CHO), 1,000 mg/kg monoethanolamine (MEA), 1,000 mg/kg lysophosphatidylcholine (LPC), or 500 mg/kg LPC + 500 mg/kg MEA (LPC + MEA). The experimental diets were isocaloric (metabolizable energy, 11.15 MJ/kg) and isonitrogenous (crude protein, 16.60%). The feeding trial lasted 28 days. Laying hen performance and egg quality were not affected (P > 0.05) by the diets used. The monounsaturated fatty acid (MUFA) level was reduced in the LPC group at d 28 (P < 0.01), whereas the polyunsaturated fatty acid (PUFA) level was increased (P < 0.05). The omega-6 (n-6) PUFA level of the egg yolks in the LPC group had a trend to increase in comparison to the control (P = 0.07). The CHO and LPC groups had higher omega-3 (n-3) PUFA and DHA levels and lower n-6/n-3 ratios than the other groups at d 28 (P < 0.01). The DHA content in egg yolk reached a plateau after the laying hens consumed the experimental diets for 14 days, and higher yolk DHA contents were observed in the CHO and LPC groups as compared with the other groups at d 14. It was concluded that dietary choline supplementation for more than 14 d enhanced egg yolk enrichment with n-3 PUFA and DHA when laying hen diets were supplemented with 2% Schizochytrium powder. All the diets had no adverse effect on hen performance, egg quality, or egg components under the experimental condition. © 2017 Poultry Science

Comparisons among serum, egg albumin and yolk concentrations of corticosterone as biomarkers of basal and stimulated adrenocortical activity of laying hens.

PubMed

Cook, N J; Renema, R; Wilkinson, C; Schaefer, A L

2009-09-01

1. Serial blood samples from individual birds were analysed for corticosterone concentrations under basal and stimulated conditions, and matched to eggs from the same birds for comparison to albumin and yolk concentrations of corticosterone. 2. Serum corticosterone exhibited increases in response to stimulation by ACTH and Handling stress. There were no significant increases in egg albumin or yolk concentrations of corticosterone following stimulation. 3. Several significant correlations were observed between the mean and area under the curve (AUC) measurements of serum corticosterone concentrations with albumin and yolk corticosterone concentrations in eggs laid from 1 to 2 d later. 4. The results demonstrated a relationship between endogenous concentrations of serum corticosterone that reflected daily adrenocortical output with albumin and yolk corticosterone concentrations in eggs laid the following day. 5. The results do not support the concept of albumin and yolk concentrations of corticosterone as biomarkers of acute adrenocortical responses to stimulation.

Silencing of Amyloid Precursor Protein Expression Using a New Engineered Delta Ribozyme

PubMed Central

Ben Aissa, Manel; April, Marie-Claude; Bergeron, Lucien-Junior; Perreault, Jean-Pierre; Levesque, Georges

2012-01-01

Alzheimer's disease (AD) etiological studies suggest that an elevation in amyloid-β peptides (Aβ) level contributes to aggregations of the peptide and subsequent development of the disease. The major constituent of these amyloid peptides is the 1 to 40–42 residue peptide (Aβ 40−42) derived from amyloid protein precursor (APP). Most likely, reducing Aβ levels in the brain may block both its aggregation and neurotoxicity and would be beneficial for patients with AD. Among the several possible ways to lower Aβ accumulation in the cells, we have selectively chosen to target the primary step in the Aβ cascade, namely, to reduce APP gene expression. Toward this end, we engineered specific SOFA-HDV ribozymes, a new generation of catalytic RNA tools, to decrease APP mRNA levels. Additionally, we demonstrated that APP-ribozymes are effective at decreasing APP mRNA and protein levels as well as Aβ levels in neuronal cells. Our results could lay the groundwork for a new protective treatment for AD. PMID:22482079

Multiple vitellogenins and product yolk proteins in European sea bass (Dicentrarchus labrax): Molecular characterization, quantification in plasma, liver and ovary, and maturational proteolysis.

PubMed

Yilmaz, Ozlem; Prat, Francisco; Ibáñez, A Jose; Köksoy, Sadi; Amano, Haruna; Sullivan, Craig V

2016-01-01

Three complete vitellogenin (Vtg) polypeptides of European sea bass (Dicentrarchus labrax), an acanthomorph teleost spawning pelagic eggs in seawater, were deduced from cDNA and identified as VtgAa, VtgAb and VtgC based on current Vtg nomenclature and phylogeny. Label free quantitative mass spectrometry verified the presence of the three sea bass Vtgs or their product yolk proteins (YPs) in liver, plasma and ovary of postvitellogenic females. As evidenced by normalized spectral counts, VtgAb-derived protein was 2- to 5-fold more abundant, depending on sample type, than for VtgAa, while VtgC-derived protein was less abundant, albeit only 3-fold lower than for VtgAb in the ovary. Western blotting with Vtg type-specific antisera raised against corresponding gray mullet (Mugil cephalus) lipovitellins (Lvs) detected all three types of sea bass Vtg in the blood plasma of gravid females and/or estrogenized males and showed that all three forms of sea bass Lv undergo limited partial degradation during oocyte maturation. The comparatively high levels of VtgC-derived YPs in fully-grown oocytes and the maturational proteolysis of all three types of Lv differ from what has been reported for other teleosts spawning pelagic eggs in seawater but are similar to recent findings for two species of North American Moronidae, the striped bass (Morone saxatilis) and white perch (Morone americana), which spawn pelagic and demersal eggs, respectively in fresh water. Together with the high Vtg sequence homologies and virtually identical structural features of each type of Vtg between species, these findings indicate that the moronid multiple Vtg systems do not substantially vary with reproductive environment. Copyright © 2015 Elsevier Inc. All rights reserved.

The crystal structure of DR6 in complex with the amyloid precursor protein provides insight into death receptor activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Kai; Olsen, Olav; Tzvetkova-Robev, Dorothea

The amyloid precursor protein (APP) has garnered considerable attention due to its genetic links to Alzheimer's disease. Death receptor 6 (DR6) was recently shown to bind APP via the protein extracellular regions, stimulate axonal pruning, and inhibit synapse formation. Here, we report the crystal structure of the DR6 ectodomain in complex with the E2 domain of APP and show that it supports a model for APP-induced dimerization and activation of cell surface DR6.

The crystal structure of DR6 in complex with the amyloid precursor protein provides insight into death receptor activation

DOE PAGES

Xu, Kai; Olsen, Olav; Tzvetkova-Robev, Dorothea; ...

2015-04-02

The amyloid precursor protein (APP) has garnered considerable attention due to its genetic links to Alzheimer's disease. Death receptor 6 (DR6) was recently shown to bind APP via the protein extracellular regions, stimulate axonal pruning, and inhibit synapse formation. Here, we report the crystal structure of the DR6 ectodomain in complex with the E2 domain of APP and show that it supports a model for APP-induced dimerization and activation of cell surface DR6.

Immunoprophylactic effect of chicken egg yolk antibody (IgY) against a recombinant S1 domain of the porcine epidemic diarrhea virus spike protein in piglets.

PubMed

Lee, Do Hyun; Jeon, Young-Soo; Park, Choi-Kyu; Kim, Seungjoon; Lee, Du Sik; Lee, Changhee

2015-09-01

Porcine epidemic diarrhea virus (PEDV) is a highly contagious enteric pathogen of swine causing high mortality rates in piglets. PEDV outbreaks have occurred continuously in most swine-producing Asian countries and have recently emerged in the United States, leading to large economic losses for both the Asian and US pig industries. The spike (S) protein of PEDV consists of the S1 and S2 domains, responsible for virus binding and fusion, respectively. The involvement of the S1 domain in specific high-affinity interactions with the cellular receptor and induction of neutralizing antibodies in the natural host makes it a logical target for the development of effective vaccines and therapeutics against PEDV. Passive immunization by oral administration of egg yolk antibodies (IgY) obtained from immunized chickens provides an alternative source of specific antibodies for the prevention and treatment of PEDV in newborn piglets. In this study, we produced an IgY against the PEDV S1 protein and investigated its immunoprophylactic effect in neonatal piglets. A codon-optimized PEDV S1 gene consisting of amino acid residues 25-749 was synthesized and used to establish a stable porcine cell line constitutively expressing a recombinant PEDV S1 protein containing the chicken immunoglobulin Fc fragment at its C-terminus. The purified recombinant S1 protein was found to mediate potent immune responses in immunized hens. We next tested the ability of oral passive immunization with anti-PEDV S1 IgY to protect piglets against PEDV. Specific chicken IgY against the S1 protein was orally administered to neonatal piglets, and their responses subsequent to a virulent PEDV challenge were monitored. The results showed that oral administration of anti-PEDV S1 IgY efficiently protects neonatal piglets against PEDV, suggesting its potential as a prophylactic or therapeutic agent against acute PEDV infection.

[Application of asymmetrical flow field-flow fractionation for size characterization of low density lipoprotein in egg yolk plasma].

PubMed

Zhang, Wenhui; Cai, Chunxue; Wang, Jing; Mao, Zhen; Li, Yueqiu; Ding, Liang; Shen, Shigang; Dou, Haiyang

2017-08-08

Home-made asymmetrical flow field-flow fractionation (AF4) system, online coupled with ultraviolet/visible (UV/Vis) detector was employed for the separation and size characterization of low density lipoprotein (LDL) in egg yolk plasma. At close to natural condition of egg yolk, the effects of cross flow rate, sample loading, and type of membrane on the size distribution of LDL were investigated. Under the optimal operation conditions, AF4-UV/Vis provides the size distribution of LDL. Moreover, the precision of AF4-UV/Vis method proposed in this work for the analysis of LDL in egg yolk plasma was evaluated. The intra-day precisions were 1.3% and 1.9% ( n =7) and the inter-day precisions were 2.4% and 2.3% ( n =7) for the elution peak height and elution peak area of LDL, respectively. Results reveal that AF4-UV/Vis is a useful tool for the separation and size characterization of LDL in egg yolk plasma.

Enzymatic enrichment of egg-yolk phosphatidylcholine with alpha-linolenic acid.

PubMed

Chojnacka, A; Gładkowski, W; Kiełbowicz, G; Wawrzeńczyk, C

2009-05-01

alpha-Linolenic acid (ALA) was incorporated at 28% into the sn-1 position of egg-yolk phospatidylcholine using Novozyme 435 in one-step transesterification process. Using phospholipase A(2) in a two-step process gave 25% incorporation of ALA into the sn-2 position.

P2 receptor stimulation induces amyloid precursor protein production and secretion in rat cortical astrocytes.

PubMed

Tran, Minh D

2011-04-04

Amyloid precursor protein (APP) is ubiquitously expressed in a variety of tissues but is predominantly expressed in the brain. The expression of APP has been well studied in neurons but little is known about its presence in astrocytes. The study presented here shows that purinergic signaling is involved in the production and secretion of APP in primary cultures of rat cortical astrocytes. Extracellular ATP caused an increase in APP production and release in a time- and concentration-dependent manner and was inhibited by antagonists of P2 receptors. Further agonist and antagonist studies revealed involvement of P2Y2 and P2Y4 receptors in nucleotide-stimulated production and release of APP. In addition, signaling studies with various protein kinase inhibitors demonstrated that blockade of mitogen-activated protein kinases, but not Akt, inhibited nucleotide-stimulated APP expression and release. These results indicate that APP production and secretion can be regulated by activation of P2Y2/4 receptors coupled to protein kinase signaling pathways and suggest that astrocytes can be a potential source of APP. Published by Elsevier Ireland Ltd.

Electrochemical immunosensor based on ensemble of nanoelectrodes for immunoglobulin IgY detection: application to identify hen's egg yolk in tempera paintings.

PubMed

Bottari, Fabio; Oliveri, Paolo; Ugo, Paolo

2014-02-15

A nanostructured electrochemical biosensor for detecting proteins of interest in work of art, in particular in tempera paintings, is presented. To determine egg yolk we focus here on the determination of immunoglobulin IgY. The transducers are nanoelectrode ensembles (NEEs), prepared via membrane templated electroless deposition of gold. Because of their geometrical and diffusion characteristics, NEEs are characterized by significantly low detection limits, moreover they display the capability of capturing proteins by interaction with the polycarbonate membrane of the NEE. At first, the proteic component of the paint is extracted by ultrasonication in an aqueous buffer, then IgY is captured by incubation on the NEE. The immunoglobulin is detected by treatment with anti-IgY labeled with horse radish peroxidase (Anti-IgY-HRP). The binding of the Anti-IgY-HRP is detected by recording the electrocatalytic signal caused by addition of H2O2 and methylene blue. The sensor detection capabilities are tested by analyzing both paint models, prepared in the lab, and real samples, from paintings of the XVIII-XX century. Multivariate exploratory analysis is applied to classify the voltammetric patterns, confirming the capability to differentiate egg-yolk tempera from other kind of tempera binders as well as from acrylic or oil paints. © 2013 Elsevier B.V. All rights reserved.

F-box only protein 2 (Fbxo2) regulates amyloid precursor protein levels and processing.

PubMed

Atkin, Graham; Hunt, Jack; Minakawa, Eiko; Sharkey, Lisa; Tipper, Nathan; Tennant, William; Paulson, Henry L

2014-03-07

The amyloid precursor protein (APP) is an integral membrane glycoprotein whose cleavage products, particularly amyloid-β, accumulate in Alzheimer disease (AD). APP is present at synapses and is thought to play a role in both the formation and plasticity of these critical neuronal structures. Despite the central role suggested for APP in AD pathogenesis, the mechanisms regulating APP in neurons and its processing into cleavage products remain incompletely understood. F-box only protein 2 (Fbxo2), a neuron-enriched ubiquitin ligase substrate adaptor that preferentially binds high-mannose glycans on glycoproteins, was previously implicated in APP processing by facilitating the degradation of the APP-cleaving β-secretase, β-site APP-cleaving enzyme. Here, we sought to determine whether Fbxo2 plays a similar role for other glycoproteins in the amyloid processing pathway. We present in vitro and in vivo evidence that APP is itself a substrate for Fbxo2. APP levels were decreased in the presence of Fbxo2 in non-neuronal cells, and increased in both cultured hippocampal neurons and brain tissue from Fbxo2 knock-out mice. The processing of APP into its cleavage products was also increased in hippocampi and cultured hippocampal neurons lacking Fbxo2. In hippocampal slices, this increase in cleavage products was accompanied by a significant reduction in APP at the cell surface. Taken together, these results suggest that Fbxo2 regulates APP levels and processing in the brain and may play a role in modulating AD pathogenesis.

Amyloid precursor protein and endosomal-lysosomal dysfunction in Alzheimer's disease: inseparable partners in a multifactorial disease.

PubMed

Nixon, Ralph A

2017-07-01

Abnormalities of the endosomal-lysosomal network (ELN) are a signature feature of Alzheimer's disease (AD). These include the earliest known cytopathology that is specific to AD and that affects endosomes and induces the progressive failure of lysosomes, each of which are directly linked by distinct mechanisms to neurodegeneration. The origins of ELN dysfunction and β-amyloidogenesis closely overlap, which reflects their common genetic basis, the established early involvement of endosomes and lysosomes in amyloid precursor protein (APP) processing and clearance, and the pathologic effect of certain APP metabolites on ELN functions. Genes that promote β-amyloidogenesis in AD (APP, PSEN1/2, and APOE4) have primary effects on ELN function. The importance of primary ELN dysfunction to pathogenesis is underscored by the mutations in more than 35 ELN-related genes that, thus far, are known to cause familial neurodegenerative diseases even though different pathogenic proteins may be involved. In this article, I discuss growing evidence that implicates AD gene-driven ELN disruptions as not only the antecedent pathobiology that underlies β-amyloidogenesis but also as the essential partner with APP and its metabolites that drive the development of AD, including tauopathy, synaptic dysfunction, and neurodegeneration. The striking amelioration of diverse deficits in animal AD models by remediating ELN dysfunction further supports a need to integrate APP and ELN relationships, including the role of amyloid-β, into a broader conceptual framework of how AD arises, progresses, and may be effectively therapeutically targeted.-Nixon, R. A. Amyloid precursor protein and endosomal-lysosomal dysfunction in Alzheimer's disease: inseparable partners in a multifactorial disease. © FASEB.

Thermal transitions in the low-density lipoprotein and lipids of the egg yolk of hens.

PubMed

Smith, M B; Back, J F

1975-05-22

1. Differential sanning calorimetry and light-scattering have been used to investigate temperature-dependent transitions in low-density lipoprotein and in lipids from hens' egg yolk. Yolks of different fatty acid composition were obtained by varying the dietary lipid and by adding methyl sterculate to the hen's diet. 2. Lipoprotein solutions in 50 percent glycerol/water gave characteristic melting curves between -25 degrees C and 50 degrees C, and on cooling showed increases in light-scattering between 10 degrees C and -20 degrees C. The temperatures at which major changes occurred depended on the proportions of saturated and unsaturated fatty acids. 3. The thermal transitions in the intact lipoprotein in glycerol solution were reversible, but with marked hysteresis. Lipid extracted from the lipoprotein did not show temperature hystersis but the transition heats and melting curves similar to those of the intact lipoprotein. The results support the hypothesis of a "lipid-core" structure for low-density lipoproteins. 4. Scanning calorimetry of egg-yolk lecithins indicated a strong dependence of transition temperature on water content in the rane 3 percent-20 percent water. A rise in the mid-temperature of the liquid-crystalline to gel transition as the water content is lowered on freezing may be the primary event in the irreversible gelation of egg yolk and aggregation of lipoprotein.

Multi-yolk-shell SnO2/Co3Sn2@C Nanocubes with High Initial Coulombic Efficiency and Oxygen Reutilization for Lithium Storage.

PubMed

Su, Liwei; Xu, Yawei; Xie, Jian; Wang, Lianbang; Wang, Yuanhao

2016-12-28

The challenging problems of SnO 2 anode material for lithium ion batteries are the poor electronic conductivity and the low oxygen reutilization due to the irreversibility of Li 2 O generated in the initial discharge leading to a theoretical initial Coulombic efficiency (ICE) of only 52.4%. Different from these strategies, this work proposes a novel strategy to level up the oxygen reutilization in SnO 2 by introducing Co 3 Sn 2 nanoalloys which can release Co atoms to reversibly react with Li 2 O instead. According to this protocol, multi-yolk-shell SnO 2 /Co 3 Sn 2 @C nanocubes are designed and successfully prepared using hollow CoSn(OH) 6 nanocubes as precursors followed a hydrothermal carbon coating and calcination treatment. The unique multi-yolk-shell nanostructure offers adequate breathing space for the volumetric deformation during long-term cycling. Moreover, the removal of Li 2 O allows a high electronic conductivity and resultant rate performance. As a result, the efficient reutilization of oxygen enables a high ICE of 71.7% and a reversible capacity of 1003 mA h g -1 after 200 cycles at 100 mA g -1 . Cyclic voltammetry, cycling performance at different voltage windows, and X-ray photoelectron spectroscopy confirm the proposed mechanism. This strategy employing oxygen-poor metals or alloys provides a novel approach to enhance the oxygen reutilization in SnO 2 for higher reversibility.

Chronobiological studies of chicken IgY: monitoring of infradian, circadian and ultradian rhythms of IgY in blood and yolk of chickens.

PubMed

He, Jin-Xin; Thirumalai, Diraviyam; Schade, Rüdiger; Zhang, Xiao-Ying

2014-08-15

IgY is the functional equivalent of mammalian IgG found in birds, reptiles and amphibians. Many of its biological aspects have been explored with different approaches. In order to evaluate the rhythmicity of serum and yolk IgY, four chickens were examined and reared under the same conditions. To monitor biological oscillations of IgY in yolk and serum, the eggs and blood samples were collected over a 60 day period and the rhythm of yolk and serum IgY was determined by direct-ELISA. Results indicated that, there is a significant circaseptan rhythm in yolk IgY and circaquattran rhythm in serum IgY. The serum IgY concentration reached a peak in the morning, decreased to a minimum during the daytime and increased again at night revealing a significant circadian rhythm was superimposed by an ultradian rhythm. These data are suited to address the controversies concerning the IgY concentration in egg yolk and blood of laying hens. In addition, this study raised new questions, if the different rhythms in yolk and serum are concerned. Copyright © 2014 Elsevier B.V. All rights reserved.

Amyloid Precursor-like Protein 2 Association with HLA Class I Molecules

PubMed Central

Tuli, Amit; Sharma, Mahak; Wang, Xiaojian; Simone, Laura C.; Capek, Haley L.; Cate, Steven; Hildebrand, William H.; Naslavsky, Naava; Caplan, Steve; Solheim, Joyce C.

2009-01-01

Amyloid precursor-like protein 2 (APLP2) is a ubiquitously expressed protein. The previously demonstrated functions for APLP2 include binding to the mouse major histocompatibility complex (MHC) class I molecule H-2Kd and down regulating its cell surface expression. In this study, we have investigated the interaction of APLP2 with the human leukocyte antigen (HLA) class I molecule in human tumor cell lines. APLP2 was readily detected in pancreatic, breast, and prostate tumor lines, although it was found only in very low amounts in lymphoma cell lines. In a pancreatic tumor cell line, HLA class I was extensively co-localized with APLP2 in vesicular compartments following endocytosis of HLA class I molecules. In pancreatic, breast, and prostate tumor lines, APLP2 was bound to the HLA class I molecule. APLP2 was found to bind to HLA-A24, and more strongly to HLA-A2. Increased expression of APLP2 resulted in reduced surface expression of HLA-A2 and HLA-A24. Overall, these studies demonstrate that APLP2 binds to the HLA class I molecule, co-localizes with it in intracellular vesicles, and reduces the level of HLA class I molecule cell surface expression. PMID:19184004

Study on development of Vipera lebetina snake anti-venom in chicken egg yolk for passive immunization

PubMed Central

Zolfagharian, Hossein; Dounighi, Naser Mohammadpour

2015-01-01

Chicken egg yolk antibodies against Vipera lebetina venom were evaluated for their antivenom potential. White leghorn hens were immunized with detoxified V. lebetina venom (γ-irradiated venom). The detoxified venom (200 μg) was mixed with an equal volume of complete Freund's adjuvant and was injected intramuscularly into the hens. The antibodies showed high activity (1.6 LD50/mL) in egg yolks after 12 d of venom injection. The eggs were collected after 12 days, and the egg yolks were removed and washed with purified water to remove any contamination with egg whites. The purification was performed using a method described by Maya Devi et al., followed by gel filtration (Sephadex G-50). The purity and molecular weight of antivenom antibodies (IgY) were determined using electrophoresis, and the molecular weight was found to be approximately 185 kDa. The potency of IgY was 6 LD50/mL (mice), i.e., 1 mL of IgY could neutralize 43.8 μg of standard V. lebetina venom). Our results showed that chicken egg yolk antibodies were effective in neutralizing the lethality and several pharmacological effects of V. lebetina venom and could be used for developing effective antivenom. PMID:25700656

Rational design and synthesis of yolk-shell ZnGa2O4@C nanostructure with enhanced lithium storage properties

NASA Astrophysics Data System (ADS)

Han, Nao; Xia, Yuguo; Han, Yanyang; Jiao, Xiuling; Chen, Dairong

2018-03-01

The ability to create hybrid nanostructure with synergistic effect and confined morphology to achieve high performance and long-term stability is high desirable in lithium ion batteries. Although transition metal oxides as anode material reveal high theoretical capacities, the significant volume changes during repeated lithium insertion and extraction cause pulverization of electrode materials, resulting in rapid fade in capacity. Herein, yolk-shell nanostructure of ZnGa2O4 encapsulated by amorphous carbon is rationally designed and synthesized through two-step surface coating followed by thermal treatment and etching process. It is noteworthy that ZnGa2O4@C with yolk-shell structure is superior to pristine ZnGa2O4 and ZnGa2O4@C with core-shell structure in term of lithium storage. The stable reversible capacity of yolk-shell ZnGa2O4@C can be retained at 657.2 mAh g-1 at current density of 1 A g-1 after completion of 300 cycles, which also reveals superior rate performance. The appropriate carbon shell and void space involved in the yolk-shell structure are considered to be the crucial factor in accommodating volume expansion as well as preserving the structural integrity of yolk-shell ZnGa2O4@C.

Comprehensive and quantitative proteomic analyses of zebrafish plasma reveals conserved protein profiles between genders and between zebrafish and human.

PubMed

Li, Caixia; Tan, Xing Fei; Lim, Teck Kwang; Lin, Qingsong; Gong, Zhiyuan

2016-04-13

Omic approaches have been increasingly used in the zebrafish model for holistic understanding of molecular events and mechanisms of tissue functions. However, plasma is rarely used for omic profiling because of the technical challenges in collecting sufficient blood. In this study, we employed two mass spectrometric (MS) approaches for a comprehensive characterization of zebrafish plasma proteome, i.e. conventional shotgun liquid chromatography-tandem mass spectrometry (LC-MS/MS) for an overview study and quantitative SWATH (Sequential Window Acquisition of all THeoretical fragment-ion spectra) for comparison between genders. 959 proteins were identified in the shotgun profiling with estimated concentrations spanning almost five orders of magnitudes. Other than the presence of a few highly abundant female egg yolk precursor proteins (vitellogenins), the proteomic profiles of male and female plasmas were very similar in both number and abundance and there were basically no other highly gender-biased proteins. The types of plasma proteins based on IPA (Ingenuity Pathway Analysis) classification and tissue sources of production were also very similar. Furthermore, the zebrafish plasma proteome shares significant similarities with human plasma proteome, in particular in top abundant proteins including apolipoproteins and complements. Thus, the current study provided a valuable dataset for future evaluation of plasma proteins in zebrafish.

Comprehensive and quantitative proteomic analyses of zebrafish plasma reveals conserved protein profiles between genders and between zebrafish and human

PubMed Central

Li, Caixia; Tan, Xing Fei; Lim, Teck Kwang; Lin, Qingsong; Gong, Zhiyuan

2016-01-01

Omic approaches have been increasingly used in the zebrafish model for holistic understanding of molecular events and mechanisms of tissue functions. However, plasma is rarely used for omic profiling because of the technical challenges in collecting sufficient blood. In this study, we employed two mass spectrometric (MS) approaches for a comprehensive characterization of zebrafish plasma proteome, i.e. conventional shotgun liquid chromatography-tandem mass spectrometry (LC-MS/MS) for an overview study and quantitative SWATH (Sequential Window Acquisition of all THeoretical fragment-ion spectra) for comparison between genders. 959 proteins were identified in the shotgun profiling with estimated concentrations spanning almost five orders of magnitudes. Other than the presence of a few highly abundant female egg yolk precursor proteins (vitellogenins), the proteomic profiles of male and female plasmas were very similar in both number and abundance and there were basically no other highly gender-biased proteins. The types of plasma proteins based on IPA (Ingenuity Pathway Analysis) classification and tissue sources of production were also very similar. Furthermore, the zebrafish plasma proteome shares significant similarities with human plasma proteome, in particular in top abundant proteins including apolipoproteins and complements. Thus, the current study provided a valuable dataset for future evaluation of plasma proteins in zebrafish. PMID:27071722

Productivity and some properties of egg yolk antibody (IgY) against human rotavirus compared with rabbit IgG.

PubMed

Hatta, H; Tsuda, K; Akachi, S; Kim, M; Yamamoto, T

1993-03-01

Productivity and some properties of anti-Human Rotavirus (HRV) hen egg yolk antibody (IgY) were compared with those of anti-HRV rabbit serum antibody (IgG). The hens immunized with HRV (Wa strain, serotype 1 and Mo strain, serotype 3) were found to continuously to lay eggs without any change in the egg laying rate and the yolk of the eggs laid over a year showed a high level of neutralization titer against HRV. The production of anti-HRV IgY by a hen (one year) was at least 15 times (anti-Wa) and 120 times (anti-Mo) more effective than those by an immunized rabbit in the neutralization titer of the antibodies. The stability of anti-HRV IgY at temperature above 70 degrees C and low pH 2-3 was less than that of anti-HRV rabbit IgG. The temperature corresponding to the maximum of denaturation endotherm (Tmax) of IgY was 73.9 degrees C while that of rabbit IgG was 77.0 degrees C in the analysis by differential scanning calorimetry. This discrepancy in heat and acidic pH stability found between the two antibodies as discussed with regard to their protein structures.

Effect of hen's egg yolk on capacitation and acrosome reaction of diluted canine spermatozoa.

PubMed

Witte, T S; Schäfer-Somi, S; Kuchar, A; Möstl, E; Iben, C; Aurich, C

2009-02-01

The aim of this study was to investigate the influence of progesterone, cholesterol and calcium (Ca(2+)) in an egg-yolk-containing extender on capacitation and acrosome reactions (AR) of diluted canine spermatozoa during 4 days of cooled-storage. For this purpose, we first investigated the effect of supplementation of a Tris-citrate-fructose buffer (TCF) with progesterone in a final concentration of 0.1, 0.2 and 1.0 microg progesterone/ml TCF-diluted semen. We then compared the effects of TCF and the same buffer-containing 20% egg yolk (TCF-EY). In egg yolks and the TCF-EY, progesterone was measured by enzyme immunoassay, cholesterol by enzymatic colorimetry and Ca(2+) by flame atomic absorption spectrophotometry. For both experiments, ejaculates from eight dogs were used. For the comparison of diluents, one ejaculate was divided and one half diluted with TCF, the other with TCF-EY. One half of each TCF- and TCF-EY-diluted sample was evaluated immediately (D1), the other after storage for 4 days at +4 degrees C (D4). In diluted semen, motility and viability were measured by a computer assisted sperm analyzer (CASA; Sperm Vision, Minitüb, Germany), capacitation and AR were evaluated with a modified chlortetracycline assay (CTC) and the AR additionally by flow cytometry. Supplementation of progesterone revealed, that between D1 and D4, total and progressive motility decreased with all progesterone concentrations, while viability as well as percentage of capacitated and acrosome reacted spermatozoa stayed constant. Progesterone-, cholesterol- and Ca(2+) concentrations in egg yolks were 524.8+/-131.4 ng/g, 13.9+/-2.03 mg/g and 1.27+/-0.17 mg/g, respectively. In the TCF-EY-diluent, the respective values were 210.9 ng/g, 2.52 mg/g and 1.1mg/g. In TCF-semen, at D1, motility and viability were significantly higher than in TCF-EY-samples (p<0.05), however at D4, no significant differences were detectable. Further, in TCF-semen, percentages of spermatozoa with intact

The Role of Wheat and Egg Constituents in the Formation of a Covalent and Non-covalent Protein Network in Fresh and Cooked Egg Noodles.

PubMed

Lambrecht, Marlies A; Rombouts, Ine; Nivelle, Mieke A; Delcour, Jan A

2017-01-01

Noodles of constant protein content and flour-to-egg protein ratio were made with whole egg, egg white, or egg yolk. The optimal cooking time, water absorption, and cooking loss of salted whole egg noodles was respectively lower and higher than of egg white and egg yolk noodles. However, cooked whole egg noodles showed the best Kieffer-rig extensibility. Differences in noodle properties were linked to protein network formation. Disulfide bonds in whole egg noodles developed faster and to a larger extent during cooking than in egg yolk noodles but slower and to a lower extent than in egg white noodles. The balance between the rate of protein cross-linking and starch swelling determines cooked noodle properties. Ionic and hydrophobic protein interactions increase the optimum cooking time and total work in Kieffer-rig extensibility testing of fresh noodles. Hydrogen bonds and covalent cross-links are probably the main determinants of the extensibility of cooked noodles. © 2016 Institute of Food Technologists®.

Yolk embolism associated with trauma in vitellogenic sea turtles in Florida (USA): a review of 11 cases.

PubMed

Stacy, Brian A; Foley, Allen; Garner, Michael M; Mettee, Nancy

2013-12-01

Case information and postmortem examination findings are presented for 11 adult female sea turtles in reproductive form that died in Florida, USA. All had abundant, large vitellogenic follicles, and most were either gravid or had recently nested. Species included six loggerheads (Caretta caretta) and five green turtles (Chelonia mydas). Identified proximate causes of death included falls or entrapment by obstructions on nesting beaches, burial under collapsed dunes, and other traumatic injuries of different causes. Evidence of yolk embolization was found in 10 cases and suspected in an 11th turtle. Ten turtles also had various amounts of free intracoelomic yolk. Although the effects of yolk embolization are uncertain at this time, precedence of pathologic importance in other species suggests that embolism may complicate traumatic injuries, including seemingly minor events.

Yolk-sac larval development of the substrate-brooding cichlid Archocentrus nigrofasciatus in relation to temperature.

PubMed

Vlahos, Nikolaos; Vasilopoulos, Michael; Mente, Eleni; Hotos, George; Katselis, George; Vidalis, Kosmas

2015-09-01

In order to conserve and culture the cichlid fish Archocentrus nigrofasciatus, more information about its reproductive biology and its larval behavior and morphogenesis is necessary. Currently, temperatures ranging from 21 to 27 °C are used in ornamental aquaculture hatcheries. Lower temperatures are preferred to reduce the costs of water heating, and 23 °C is usually the selected temperature. However, there is limited information on culturing protocols for ornamental species and most of the information generated on this topic remains scarce. Thus, the present study examines the morphological development of Archocentrus nigrofasciatus during the yolk-sac period up to the age of 100 h post-hatching in relation to 2 temperature regimes used in ornamental aquaculture: a temperature of 27 °C (thermal optimum) and a decreased temperature of 23 °C (thermal tolerance). The results of this study suggest that the 27 °C temperature generates intense morphological changes in yolk-sac development in a shorter period. This has advantages as it reduces the time of yolk-sac larval development, and, thus, minimizes the transition phase to exogenous feeding and maximizes the efficiency at which yolk is converted into body tissues. The present paper provides necessary information to produce freshwater ornamental fish with better practices so as to increase larval survival and capitalize on time for growth. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Sex-biased investment in yolk androgens depends on female quality and laying order in zebra finches (Taeniopygia guttata)

NASA Astrophysics Data System (ADS)

Gilbert, Lucy; Rutstein, Alison N.; Hazon, Neil; Graves, Jefferson A.

2005-04-01

The Trivers-Willard hypothesis predicts sex biases in parental investment according to parental condition. In addition, parents may need to sex bias their investment if there is an asymmetry between the sexes in offspring fitness under different conditions. For studying maternal differential investment, egg resources are ideal subjects because they are self contained and allocated unequivocally by the female. Recent studies show that yolk androgens can be beneficial to offspring, so here we test for sex-biased investment with maternal investment of yolk testosterone (T) in zebra finch (Taeniopygia guttata) eggs. From the Trivers-Willard hypothesis, we predicted females to invest more in male eggs in optimum circumstances (e.g. good-condition mother, early-laid egg), and more in female eggs under suboptimal conditions (e.g. poor-condition mother, late-laid egg). This latter prediction is also because in this species there is a female nestling disadvantage in poor conditions and we expected mothers to help compensate for this in female eggs. Indeed, we found more yolk T in female than male eggs. Moreover, in accordance with our predictions, yolk T in male eggs increased with maternal quality relative to female eggs, and decreased with laying order relative to female eggs. This supports our predictions for the different needs and value of male and female offspring in zebra finches. Our results support the idea that females may use yolk androgens as a tool to adaptively manipulate the inequalities between different nestlings.

General route to multifunctional uniform yolk/mesoporous silica shell nanocapsules: a platform for simultaneous cancer-targeted imaging and magnetically guided drug delivery.

PubMed

Zhang, Lingyu; Wang, Tingting; Yang, Lei; Liu, Cong; Wang, Chungang; Liu, Haiyan; Wang, Y Andrew; Su, Zhongmin

2012-09-24

Hollow mesoporous SiO(2) (mSiO(2)) nanostructures with movable nanoparticles (NPs) as cores, so-called yolk-shell nanocapsules (NCs), have attracted great research interest. However, a highly efficient, simple and general way to produce yolk-mSiO(2) shell NCs with tunable functional cores and shell compositions is still a great challenge. A facile, general and reproducible strategy has been developed for fabricating discrete, monodisperse and highly uniform yolk-shell NCs under mild conditions, composed of mSiO(2) shells and diverse functional NP cores with different compositions and shapes. These NPs can be Fe(3)O(4) NPs, gold nanorods (GNRs), and rare-earth upconversion NRs, endowing the yolk-mSiO(2) shell NCs with magnetic, plasmonic, and upconversion fluorescent properties. In addition, multifunctional yolk-shell NCs with tunable interior hollow spaces and mSiO(2) shell thickness can be precisely controlled. More importantly, fluorescent-magnetic-biotargeting multifunctional polyethyleneimine (PEI)-modified fluorescent Fe(3)O(4)@mSiO(2) yolk-shell nanobioprobes as an example for simultaneous targeted fluorescence imaging and magnetically guided drug delivery to liver cancer cells is also demonstrated. This synthetic approach can be easily extended to the fabrication of multifunctional yolk@mSiO(2) shell nanostructures that encapsulate various functional movable NP cores, which construct a potential platform for the simultaneous targeted delivery of drug/gene/DNA/siRNA and bio-imaging. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bidirectional Regulation of Amyloid Precursor Protein-Induced Memory Defects by Nebula/DSCR1: A Protein Upregulated in Alzheimer's Disease and Down Syndrome

PubMed Central

Shaw, Jillian L.; Zhang, Shixing

2015-01-01

Aging individuals with Down syndrome (DS) have an increased risk of developing Alzheimer's disease (AD), a neurodegenerative disorder characterized by impaired memory. Memory problems in both DS and AD individuals usually develop slowly and progressively get worse with age, but the cause of this age-dependent memory impairment is not well understood. This study examines the functional interactions between Down syndrome critical region 1 (DSCR1) and amyloid-precursor protein (APP), proteins upregulated in both DS and AD, in regulating memory. Using Drosophila as a model, we find that overexpression of nebula (fly homolog of DSCR1) initially protects against APP-induced memory defects by correcting calcineurin and cAMP signaling pathways but accelerates the rate of memory loss and exacerbates mitochondrial dysfunction in older animals. We report that transient upregulation of Nebula/DSCR1 or acute pharmacological inhibition of calcineurin in aged flies protected against APP-induced memory loss. Our data suggest that calcineurin dyshomeostasis underlies age-dependent memory impairments and further imply that chronic Nebula/DSCR1 upregulation may contribute to age-dependent memory impairments in AD in DS. SIGNIFICANCE STATEMENT Most Down syndrome (DS) individuals eventually develop Alzheimer's disease (AD)-like dementia, but mechanisms underlying this age-dependent memory impairment remain poorly understood. This study examines Nebula/Down syndrome critical region 1 (DSCR1) and amyloid-precursor protein (APP), proteins upregulated in both DS and AD, in regulating memory. We uncover a previously unidentified role for Nebula/DSCR1 in modulating APP-induced memory defects during aging. We show that upregulation of Nebula/DSCR1, an inhibitor of calcineurin, rescues APP-induced memory defects in young flies but enhances memory loss of older flies. Excitingly, transient Nebula/DSCR1 overexpression or calcineurin inhibition in aged flies ameliorates APP-mediated memory

Bidirectional Regulation of Amyloid Precursor Protein-Induced Memory Defects by Nebula/DSCR1: A Protein Upregulated in Alzheimer's Disease and Down Syndrome.

PubMed

Shaw, Jillian L; Zhang, Shixing; Chang, Karen T

2015-08-12

Aging individuals with Down syndrome (DS) have an increased risk of developing Alzheimer's disease (AD), a neurodegenerative disorder characterized by impaired memory. Memory problems in both DS and AD individuals usually develop slowly and progressively get worse with age, but the cause of this age-dependent memory impairment is not well understood. This study examines the functional interactions between Down syndrome critical region 1 (DSCR1) and amyloid-precursor protein (APP), proteins upregulated in both DS and AD, in regulating memory. Using Drosophila as a model, we find that overexpression of nebula (fly homolog of DSCR1) initially protects against APP-induced memory defects by correcting calcineurin and cAMP signaling pathways but accelerates the rate of memory loss and exacerbates mitochondrial dysfunction in older animals. We report that transient upregulation of Nebula/DSCR1 or acute pharmacological inhibition of calcineurin in aged flies protected against APP-induced memory loss. Our data suggest that calcineurin dyshomeostasis underlies age-dependent memory impairments and further imply that chronic Nebula/DSCR1 upregulation may contribute to age-dependent memory impairments in AD in DS. Most Down syndrome (DS) individuals eventually develop Alzheimer's disease (AD)-like dementia, but mechanisms underlying this age-dependent memory impairment remain poorly understood. This study examines Nebula/Down syndrome critical region 1 (DSCR1) and amyloid-precursor protein (APP), proteins upregulated in both DS and AD, in regulating memory. We uncover a previously unidentified role for Nebula/DSCR1 in modulating APP-induced memory defects during aging. We show that upregulation of Nebula/DSCR1, an inhibitor of calcineurin, rescues APP-induced memory defects in young flies but enhances memory loss of older flies. Excitingly, transient Nebula/DSCR1 overexpression or calcineurin inhibition in aged flies ameliorates APP-mediated memory problems. These results

The Cellular Chaperone Heat Shock Protein 90 Is Required for Foot-and-Mouth Disease Virus Capsid Precursor Processing and Assembly of Capsid Pentamers.

PubMed

Newman, Joseph; Asfor, Amin S; Berryman, Stephen; Jackson, Terry; Curry, Stephen; Tuthill, Tobias J

2018-03-01

Productive picornavirus infection requires the hijacking of host cell pathways to aid with the different stages of virus entry, synthesis of the viral polyprotein, and viral genome replication. Many picornaviruses, including foot-and-mouth disease virus (FMDV), assemble capsids via the multimerization of several copies of a single capsid precursor protein into a pentameric subunit which further encapsidates the RNA. Pentamer formation is preceded by co- and posttranslational modification of the capsid precursor (P1-2A) by viral and cellular enzymes and the subsequent rearrangement of P1-2A into a structure amenable to pentamer formation. We have developed a cell-free system to study FMDV pentamer assembly using recombinantly expressed FMDV capsid precursor and 3C protease. Using this assay, we have shown that two structurally different inhibitors of the cellular chaperone heat shock protein 90 (hsp90) impeded FMDV capsid precursor processing and subsequent pentamer formation. Treatment of FMDV permissive cells with the hsp90 inhibitor prior to infection reduced the endpoint titer by more than 10-fold while not affecting the activity of a subgenomic replicon, indicating that translation and replication of viral RNA were unaffected by the drug. IMPORTANCE FMDV of the Picornaviridae family is a pathogen of huge economic importance to the livestock industry due to its effect on the restriction of livestock movement and necessary control measures required following an outbreak. The study of FMDV capsid assembly, and picornavirus capsid assembly more generally, has tended to be focused upon the formation of capsids from pentameric intermediates or the immediate cotranslational modification of the capsid precursor protein. Here, we describe a system to analyze the early stages of FMDV pentameric capsid intermediate assembly and demonstrate a novel requirement for the cellular chaperone hsp90 in the formation of these pentameric intermediates. We show the added complexity

Treatment with thiamine hydrochloride and astaxanthine for the prevention of yolk-sac mortality in Baltic salmon fry (M74 syndrome).

PubMed

Koski, P; Pakarinen, M; Nakari, T; Soivio, A; Hartikainen, K

1999-09-14

Two practical methods are reported for treating feral Baltic salmon with thiamine hydrochloride against M74 syndrome (abnormally high yolk-sac fry mortality of the Baltic salmon). Both bathing of the yolk-sac fry in thiamine hydrochloride (1000 mg l-1, 1 h) and a single intraperitoneal injection given to the female brood fish (100 mg kg-1 fish) during the summer 3 mo before stripping were shown to elevate the whole body total thiamine concentration in the fry. Both treatments were also shown to be effective in preventing mortality due to M74 syndrome. The effect of bathing the yolk-sac fry was shown to be dose-dependent. The results support the view that there is a causal relationship between the thiamine status of the yolk-sac fry and M74 mortality. An intraperitoneal injection of astaxanthine suspension administered to the female brood fish (11 mg kg-1 fish) in the summer 3 mo before stripping elevated the astaxanthine concentration in the eggs but did not affect mortality due to M74 syndrome. An interaction between astaxanthine and thiamine may occur in the developing embryo or yolk-sac fry, however. No association could be demonstrated between the various thiamine hydrochloride treatment practices and hepatic cytochrome P450 dependent 7-ethoxyresorufin-O-deethylase (EROD) activity in the yolk-sac fry. An injection of thiamine hydrochloride into the peritoneal cavity of wild Baltic salmon females could be used to raise thiamine concentrations in their offspring in the rivers. The effect on smolt production in Finnish Baltic salmon rivers needs to be investigated further, however.

Supplementation of laying-hen feed with palm tocos and algae astaxanthin for egg yolk nutrient enrichment.

PubMed

Walker, Laurie A; Wang, Tong; Xin, Hongwei; Dolde, David

2012-02-29

Adding supplements to hen feed can increase egg nutritional value. Astaxanthin, tocotrienols, and tocopherols are potent antioxidants that provide health benefits to humans. We hypothesized that the addition of these nutrients to hen feed would result in an increased nutrient content in egg yolk with minimum changes in functional properties. Laying hens (Hy-Line W-36 breed) were fed four diets with different supplementation levels of palm toco concentrate and algae biomass containing astaxanthin for 8 weeks. Egg yolks were analyzed for physical, chemical, and functional properties. The feed with the highest nutrient concentration was also studied for stability of these antioxidants using the Arrhenius approach. No significant differences were observed in functional properties except for emulsification capacity and sensory characteristics among eggs from different diet treatments. Changes in egg yolk color reached the maximum values at day 8. Incorporation of tocopherols and tocotrienols increased until day 8, astaxanthin incorporation increased until day 10, and all decreased thereafter. Feed nutrients resulted in a dose-response relationship of these compounds in the egg yolk. The transfer efficiency ranged from 0 to 9.9% for tocotrienols and tocopherols and from 7.6 to 14.9% for astaxanthin at their peak values. Results of the Arrhenius accelerated stability study showed significant differences in the shelf life of various nutrients, and these results can be used to properly formulate and store the feed materials.

Membrane microdomain switching: a regulatory mechanism of amyloid precursor protein processing.

PubMed

Sakurai, Takashi; Kaneko, Kumi; Okuno, Misako; Wada, Koji; Kashiyama, Taku; Shimizu, Hideaki; Akagi, Takumi; Hashikawa, Tsutomu; Nukina, Nobuyuki

2008-10-20

Neuronal activity has an impact on beta cleavage of amyloid precursor protein (APP) by BACE1 to generate amyloid-beta peptide (Abeta). However, the molecular mechanisms underlying this effect remain to be elucidated. Cholesterol dependency of beta cleavage prompted us to analyze immunoisolated APP-containing detergent-resistant membranes from rodent brains. We found syntaxin 1 as a key molecule for activity-dependent regulation of APP processing in cholesterol-dependent microdomains. In living cells, APP associates with syntaxin 1-containing microdomains through X11-Munc18, which inhibits the APP-BACE1 interaction and beta cleavage via microdomain segregation. Phosphorylation of Munc18 by cdk5 causes a shift of APP to BACE1-containing microdomains. Neuronal hyperactivity, implicated in Abeta overproduction, promotes the switching of APP microdomain association as well as beta cleavage in a partially cdk5-dependent manner. We propose that microdomain switching is a mechanism of cholesterol- and activity-dependent regulation of APP processing in neurons.

Membrane microdomain switching: a regulatory mechanism of amyloid precursor protein processing

PubMed Central

Sakurai, Takashi; Kaneko, Kumi; Okuno, Misako; Wada, Koji; Kashiyama, Taku; Shimizu, Hideaki; Akagi, Takumi; Hashikawa, Tsutomu; Nukina, Nobuyuki

2008-01-01

Neuronal activity has an impact on β cleavage of amyloid precursor protein (APP) by BACE1 to generate amyloid-β peptide (Aβ). However, the molecular mechanisms underlying this effect remain to be elucidated. Cholesterol dependency of β cleavage prompted us to analyze immunoisolated APP-containing detergent-resistant membranes from rodent brains. We found syntaxin 1 as a key molecule for activity-dependent regulation of APP processing in cholesterol-dependent microdomains. In living cells, APP associates with syntaxin 1–containing microdomains through X11–Munc18, which inhibits the APP–BACE1 interaction and β cleavage via microdomain segregation. Phosphorylation of Munc18 by cdk5 causes a shift of APP to BACE1-containing microdomains. Neuronal hyperactivity, implicated in Aβ overproduction, promotes the switching of APP microdomain association as well as β cleavage in a partially cdk5-dependent manner. We propose that microdomain switching is a mechanism of cholesterol- and activity-dependent regulation of APP processing in neurons. PMID:18936252

Tyrosine Binding Protein Sites Regulate the Intracellular Trafficking and Processing of Amyloid Precursor Protein through a Novel Lysosome-Directed Pathway.

PubMed

Tam, Joshua H K; Cobb, M Rebecca; Seah, Claudia; Pasternak, Stephen H

2016-01-01

The amyloid hypothesis posits that the production of β-amyloid (Aβ) aggregates leads to neurodegeneration and cognitive decline associated with AD. Aβ is produced by sequential cleavage of the amyloid precursor protein (APP) by β- and γ-secretase. While nascent APP is well known to transit to the endosomal/ lysosomal system via the cell surface, we have recently shown that APP can also traffic to lysosomes intracellularly via its interaction with AP-3. Because AP-3 interacts with cargo protein via interaction with tyrosine motifs, we mutated the three tyrosines motif in the cytoplasmic tail of APP. Here, we show that the YTSI motif interacts with AP-3, and phosphorylation of the serine in this motif disrupts the interaction and decreases APP trafficking to lysosomes. Furthermore, we show that phosphorylation at this motif can decrease the production of neurotoxic Aβ 42. This demonstrates that reducing APP trafficking to lysosomes may be a strategy to reduce Aβ 42 in Alzheimer's disease.

Tyrosine Binding Protein Sites Regulate the Intracellular Trafficking and Processing of Amyloid Precursor Protein through a Novel Lysosome-Directed Pathway

PubMed Central

Tam, Joshua H. K.; Cobb, M. Rebecca; Seah, Claudia; Pasternak, Stephen H.

2016-01-01

The amyloid hypothesis posits that the production of β-amyloid (Aβ) aggregates leads to neurodegeneration and cognitive decline associated with AD. Aβ is produced by sequential cleavage of the amyloid precursor protein (APP) by β- and γ-secretase. While nascent APP is well known to transit to the endosomal/ lysosomal system via the cell surface, we have recently shown that APP can also traffic to lysosomes intracellularly via its interaction with AP-3. Because AP-3 interacts with cargo protein via interaction with tyrosine motifs, we mutated the three tyrosines motif in the cytoplasmic tail of APP. Here, we show that the YTSI motif interacts with AP-3, and phosphorylation of the serine in this motif disrupts the interaction and decreases APP trafficking to lysosomes. Furthermore, we show that phosphorylation at this motif can decrease the production of neurotoxic Aβ 42. This demonstrates that reducing APP trafficking to lysosomes may be a strategy to reduce Aβ 42 in Alzheimer’s disease. PMID:27776132

Herbal adaptogens combined with protein fractions from bovine colostrum and hen egg yolk reduce liver TNF-α expression and protein carbonylation in Western diet feeding in rats.

PubMed

Mobley, C Brooks; Toedebusch, Ryan G; Lockwood, Christopher M; Heese, Alexander J; Zhu, Conan; Krieger, Anna E; Cruthirds, Clayton L; Hofheins, John C; Company, Joseph M; Wiedmeyer, Charles E; Kim, Dae Y; Booth, Frank W; Roberts, Michael D

2014-01-01

We examined if a purported anti-inflammatory supplement (AF) abrogated Western-diet (WD)-induced liver pathology in rats. AF contained: 1) protein concentrates from bovine colostrum and avian egg yolk; 2) herbal adaptogens and antioxidants; and 3) acetyl-L-carnitine. Nine month-old male Brown Norway rats were allowed ad libitum access to WD for 41-43 days and randomly assigned to WD + AF feeding twice daily for the last 31-33 days (n = 8), or WD and water-placebo feeding twice daily for the last 31-33 days (n = 8). Rats fed a low-fat/low-sucrose diet (CTL, n = 6) for 41-43 days and administered a water-placebo twice daily for the last 31-33 days were also studied. Twenty-four hours following the last gavage-feed, liver samples were analyzed for: a) select mRNAs (via RT-PCR) as well as genome-wide mRNA expression patterns (via RNA-seq); b) lipid deposition; and, c) protein carbonyl and total antioxidant capacity (TAC). Serum was also examined for TAC, 8-isoprostane and clinical chemistry markers. WD + AF rats experienced a reduction in liver Tnf-α mRNA (-2.8-fold, p < 0.01). Serum and liver TAC was lower in WD + AF versus WD and CTL rats (p < 0.05), likely due to exogenous antioxidant ingredients provided through AF as evidenced by a tendency for mitochondrial SOD2 mRNA to increase in WD + AF versus CTL rats (p = 0.07). Liver fat deposition nor liver protein carbonyl content differed between WD + AF versus WD rats, although liver protein carbonyls tended to be lower in WD + AF versus CTL rats (p = 0.08). RNA-seq revealed that 19 liver mRNAs differed between WD + AF versus WD when both groups were compared with CTL rats (+/- 1.5-fold, p < 0.01). Bioinformatics suggest that AF prevented WD-induced alterations in select genes related to the transport and metabolism of carbohydrates in favor of select genes related to lipid transport and metabolism. Finally, serum clinical safety markers and liver pathology

Two forms of Vibrio cholerae O1 El Tor hemolysin derived from identical precursor protein.

PubMed

Ikigai, H; Ono, T; Nakae, T; Otsuru, H; Shimamura, T

1999-01-08

Vibrio cholerae O1 grown in heart infusion broth produces two forms of El Tor hemolysin (ETH) monomers of 65 and 50 kDa. These monomers form several different sizes of mixed oligomers ranging from 180 to 280 kDa in the liposomal membranes. We found that the N-terminal amino acid sequences, NH2-Trp-Pro-Ala-Pro-Ala-Asn-Ser-Glu, of both the 65- and 50-kDa toxins were identical. We assumed, therefore, that the 65- and 50-kDa toxins were derivatives of the identical precursor protein and the 50-kDa protein was a truncated derivative of 65-kDa ETH. To substantiate this assumption, we treated the 260-kDa oligomer with trypsin and obtained a 190-kDa oligomer. This 190-kDa oligomer consisted of only the 50-kDa subunits. Both 260- and 190-kDa oligomers formed ion channels indistinguishable from each other in planar lipid bilayers. These results suggest that the essential part of the ETH in forming the membrane-damaging aggregate is a 50-kDa protein.

Phosphatidylcholine from "Healthful" Egg Yolk Varieties: An Organic Laboratory Experience

NASA Astrophysics Data System (ADS)

Hodges, Linda C.

1995-12-01

I have added an investigative element to a popular undergraduate experiment. the characterization of phosphatidylcholine (PC) from egg yolks. Varieties of eggs are commercially available which have been obtained from chickens fed a diet containing no animal fat. Presumably, less saturated fat in the diet of the chickens could be reflected in the fatty acid composition of various classes of biological lipids, including phospholipids, in the eggs from these chickens. PC is extracted using conventional methods, the extract is further purified by chromatography on silicic acid, and the column fractions are assayed for the presence and purity of PC by TLC. Fractions containing pure PC are pooled, concentrated, hydrolyzed, and esterified to obtain the fatty acid methyl esters (FAME) which are identified by GLC. Comparing FAMEs derived from PC of yolks of regular eggs to those obtained from the other special brands adds a novel twist to the students' work and generates greater student interest and involvement in both the interpretation of data than a simple isolation of a biological compound alone evokes.

Characterization of the beta amyloid precursor protein-like gene in the central nervous system of the crab Chasmagnathus. Expression during memory consolidation.

PubMed

Fustiñana, Maria Sol; Ariel, Pablo; Federman, Noel; Freudenthal, Ramiro; Romano, Arturo

2010-09-01

Human β-amyloid, the main component in the neuritic plaques found in patients with Alzheimer's disease, is generated by cleavage of the β-amyloid precursor protein. Beyond the role in pathology, members of this protein family are synaptic proteins and have been associated with synaptogenesis, neuronal plasticity and memory, both in vertebrates and in invertebrates. Consolidation is necessary to convert a short-term labile memory to a long-term and stable form. During consolidation, gene expression and de novo protein synthesis are regulated in order to produce key proteins for the maintenance of plastic changes produced during the acquisition of new information. Here we partially cloned and sequenced the beta-amyloid precursor protein like gene homologue in the crab Chasmagnathus (cappl), showing a 37% of identity with the fruit fly Drosophila melanogaster homologue and 23% with Homo sapiens but with much higher degree of sequence similarity in certain regions. We observed a wide distribution of cappl mRNA in the nervous system as well as in muscle and gills. The protein localized in all tissues analyzed with the exception of muscle. Immunofluorescence revealed localization of cAPPL in associative and sensory brain areas. We studied gene and protein expression during long-term memory consolidation using a well characterized memory model: the context-signal associative memory in this crab species. mRNA levels varied at different time points during long-term memory consolidation and correlated with cAPPL protein levels cAPPL mRNA and protein is widely distributed in the central nervous system of the crab and the time course of expression suggests a role of cAPPL during long-term memory formation.

Amyloid beta precursor protein regulates male sexual behavior.

PubMed

Park, Jin Ho; Bonthius, Paul J; Tsai, Houng-Wei; Bekiranov, Stefan; Rissman, Emilie F

2010-07-28

Sexual behavior is variable between individuals, ranging from celibacy to sexual addictions. Within normal populations of individual men, ranging from young to middle aged, testosterone levels do not correlate with libido. To study the genetic mechanisms that contribute to individual differences in male sexual behavior, we used hybrid B6D2F1 male mice, which are a cross between two common inbred strains (C57BL/6J and DBA/2J). Unlike most laboratory rodent species in which male sexual behavior is highly dependent upon gonadal steroids, sexual behavior in a large proportion of these hybrid male mice after castration is independent of gonadal steroid hormones and their receptors; thus, we have the ability to discover novel genes involved in this behavior. Gene expression arrays, validation of gene candidates, and transgenic mice that overexpress one of the genes of interest were used to reveal genes involved in maintenance of male sexual behavior. Several genes related to neuroprotection and neurodegeneration were differentially expressed in the hypothalamus of males that continued to mate after castration. Male mice overexpressing the human form of one of these candidate genes, amyloid beta precursor protein (APP), displayed enhanced sexual behavior before castration and maintained sexual activity for a longer duration after castration compared with controls. Our results reveal a novel and unexpected relationship between APP and male sexual behavior. We speculate that declining APP during normal aging in males may contribute to the loss of sexual function.

N-doped yolk-shell hollow carbon sphere wrapped with graphene as sulfur host for high-performance lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Zhang, Yongzheng; Sun, Kai; Liang, Zhan; Wang, Yanli; Ling, Licheng

2018-01-01

N-doped yolk-shell hollow carbon sphere wrapped with reduced graphene oxide (rGO/N-YSHCS) is designed and fabricated as sulfur host for lithium-sulfur batteries. The shuttle effect of polysulfides can be suppressed effectively by the porous yolk-shell structure, graphene layer and N-doping. A good conductivity network is provided for electron transportation through the graphene layer coupled with the unique yolk-shell carbon matrix. Such unique structure offers the synthesized rGO/N-YSHCS/S electrode with a high reversible capacity (800 mAh g-1 at 0.2 C after 100 cycles) and good high-rate capability (636 mAh g-1 at 1 C and 540 mAh g-1 at 2 C).

COPS5 (Jab1) protein increases β site processing of amyloid precursor protein and amyloid β peptide generation by stabilizing RanBP9 protein levels.

PubMed

Wang, Hongjie; Dey, Debleena; Carrera, Ivan; Minond, Dmitriy; Bianchi, Elisabetta; Xu, Shaohua; Lakshmana, Madepalli K

2013-09-13

Increased processing of amyloid precursor protein (APP) and accumulation of neurotoxic amyloid β peptide (Aβ) in the brain is central to the pathogenesis of Alzheimer's disease (AD). Therefore, the identification of molecules that regulate Aβ generation is crucial for future therapeutic approaches for AD. We demonstrated previously that RanBP9 regulates Aβ generation in a number of cell lines and primary neuronal cultures by forming tripartite protein complexes with APP, low-density lipoprotein-related protein, and BACE1, consequently leading to increased amyloid plaque burden in the brain. RanBP9 is a scaffold protein that exists and functions in multiprotein complexes. To identify other proteins that may bind RanBP9 and regulate Aβ levels, we used a two-hybrid analysis against a human brain cDNA library and identified COPS5 as a novel RanBP9-interacting protein. This interaction was confirmed by coimmunoprecipitation experiments in both neuronal and non-neuronal cells and mouse brain. Colocalization of COPS5 and RanBP9 in the same subcellular compartments further supported the interaction of both proteins. Furthermore, like RanBP9, COPS5 robustly increased Aβ generation, followed by increased soluble APP-β (sAPP-β) and decreased soluble-APP-α (sAPP-α) levels. Most importantly, down-regulation of COPS5 by siRNAs reduced Aβ generation, implying that endogenous COPS5 regulates Aβ generation. Finally, COPS5 levels were increased significantly in AD brains and APΔE9 transgenic mice, and overexpression of COPS5 strongly increased RanBP9 protein levels by increasing its half-life. Taken together, these results suggest that COPS5 increases Aβ generation by increasing RanBP9 levels. Thus, COPS5 is a novel RanBP9-binding protein that increases APP processing and Aβ generation by stabilizing RanBP9 protein levels.

beta. -Amyloid precursor protein of Alzheimer disease occurs as 110- to 135-kilodalton membrane-associated proteins in neural and nonneural tissues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Selkoe, D.J.; Podlisny, M.B.; Joachim, C.L.

1988-10-01

Progressive cerebral deposition of extracellular filaments composed of the {beta}-amyloid protein ({beta}AP) is a constant feature of Alzheimer disease (AD). Since the gene on chromosome 21 encoding the {beta}AP precursor ({beta}APP) is not known to be altered in AD, transcriptional or posttranslational changes may underlie accelerated {beta}AP deposition. Using two antibodies to the predicted carboxyl terminus of {beta}APP, the authors have identified the native {beta}APP in brain and nonneural human tissues as a 110- to 135-kDa protein complex that is insoluble in buffer and found in various membrane-rich subcellular fractions. These proteins are relatively uniformly distributed in adult brain, abundantmore » in fetal brain, and detected in nonneural tissues that contain {beta}APP mRNA. Similarly sized proteins occur in rat, cow, and monkey brain and in cultured human HL-60 and HeLa cells; the precise patterns in the 110- to 135-kDa range are heterogeneous among various tissues and cell lines. They conclude that the highly conserved {beta}APP molecule occurs in mammalian tissues as a heterogeneous group of membrane-associated proteins of {approx} 120 kDa. Detection of the nonamyloidogenic carboxyl terminus within plaques suggests that proteolytic processing of the {beta}APP into insoluble filaments occurs locally in cortical regions that develop {beta}-amyloid deposits with age.« less

Amyloid-β protein precursor regulates phosphorylation and cellular compartmentalization of microtubule associated protein tau.

PubMed

Nizzari, Mario; Barbieri, Federica; Gentile, Maria Teresa; Passarella, Daniela; Caorsi, Calentina; Diaspro, Alberto; Taglialatela, Maurizio; Pagano, Aldo; Colucci-D'Amato, Luca; Florio, Tullio; Russo, Claudio

2012-01-01

Tau is a multifunctional protein detected in different cellular compartments in neuronal and non-neuronal cells. When hyperphosphorylated and aggregated in atrophic neurons, tau is considered the culprit for neuronal death in familial and sporadic tauopathies. With regards to Alzheimer's disease (AD) pathogenesis, it is not yet established whether entangled tau represents a cause or a consequence of neurodegeneration. In fact, it is unquestionably accepted that amyloid-β protein precursor (AβPP) plays a pivotal role in the genesis of the disease, and it is postulated that the formation of toxic amyloid-β peptides from AβPP is the primary event that subsequently induces abnormal tau phosphorylation. In this work, we show that in the brain of AD patients there is an imbalance between the nuclear and the cytoskeletal pools of phospho-tau. We observed that in non-AD subjects, there is a stable pool of phospho-tau which remains strictly confined to neuronal nuclei, while nuclear localization of phospho-tau is significantly underrepresented in neurons of AD patients bearing neurofibrillary tangles. A specific phosphorylation of tau is required during mitosis in vitro and in vivo, likely via a Grb2-ERK1/2 signaling cascade. In differentiated neuronal A1 cells, the overexpression of AβPP modulates tau phosphorylation, altering the ratio between cytoskeletal and nuclear pools, and correlates with cell death. Altogether our data provide evidence that AβPP, in addition to amyloid formation, modulates the phosphorylation of tau and its subcellular compartmentalization, an event that may lead to the formation of neurofibrillary tangles and to neurodegeneration when occurring in postmitotic neurons.

The functional property of egg yolk phosvitin as a melanogenesis inhibitor.

PubMed

Jung, Samooel; Kim, Dong Hee; Son, Jun Ho; Nam, Kichang; Ahn, Dong Uk; Jo, Cheorun

2012-12-01

Phosvitin is a phosphoglycoprotein present in egg yolk. More than half of the amino acids in phosvitin molecule are serine, of which >90% are phosphorylated. Therefore, phosvitin has a strong metal binding capability. The aim of this study was to investigate the effect of phosvitin on the inhibition of melanogenesis in melanoma cells. The results showed that phosvitin inhibited the activity of mushroom tyrosinase. Addition of phosvitin at a concentration of 50μg/ml, to B16F10 melanoma cells inhibited tyrosinase activity by approximately 42% and melanin synthesis by 17% compared to those in a control without phosvitin. Phosvitin inhibited the expression of tyrosinase, tyrosinase-related protein 1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF) in B16F10 melanoma cells. In addition, phosvitin reduced the cellular cAMP concentration in B16F10 melanoma cells. These results indicate that phosvitin has the potential to be used as a melanogenesis inhibitor in the food and cosmetics industry. Copyright © 2012 Elsevier Ltd. All rights reserved.

A canine model of Alzheimer's disease generated by overexpressing a mutated human amyloid precursor protein.

PubMed

Lee, Geun-Shik; Jeong, Yeon Woo; Kim, Joung Joo; Park, Sun Woo; Ko, Kyeong Hee; Kang, Mina; Kim, Yu Kyung; Jung, Eui-Man; Moon, Changjong; Hyun, Sang Hwan; Hwang, Kyu-Chan; Kim, Nam-Hyung; Shin, Taeyoung; Jeung, Eui-Bae; Hwang, Woo Suk

2014-04-01

Canines are considered the most authentic model for studying multifactorial human diseases, as these animals typically share a common environment with man. Somatic cell nuclear transfer (SCNT) technology along with genetic engineering of nuclear donor cells provides a unique opportunity for examining human diseases using transgenic canines. In the present study, we generated transgenic canines that overexpressed the human amyloid precursor protein (APP) gene containing well-characterized familial Alzheimer's disease (AD) mutations. We successfully obtained five out of six live puppies by SCNT. This was confirmed by observing the expression of green fluorescence protein in the body as a visual transgenic marker and the overexpression of the mutated APP gene in the brain. The transgenic canines developed AD-like symptoms, such as enlarged ventricles, an atrophied hippocampus, and β-amyloid plaques in the brain. Thus, the transgenic canines we created can serve as a novel animal model for studying human AD.

Self-template synthesis of yolk-shelled NiCo2O4 spheres for enhanced hybrid supercapacitors

NASA Astrophysics Data System (ADS)

Wang, Liang; Jiao, Xinyan; Liu, Peng; Ouyang, Yu; Xia, Xifeng; Lei, Wu; Hao, Qingli

2018-01-01

A self-template method is developed for hierarchically yolk-shelled NiCo2O4 spheres (YS-NiCo2O4) through a controlled hydrolysis process and followed by a thermal annealing treatment. The yolk-shelled NiCo2O4 spheres possess out-shell consisting of hundreds of ultrathin sheets with 3-5 nm in thickness and solid yolk composing of a large number of nanoparticles. The YS-NiCo2O4 generates a large specific surface area of 169.6 m2 g-1. Benefit from the large specific surface area and rich oxygen vacancy, the as-fabricated YS-NiCo2O4 as electrode materials for supercapacitor exhibits high specific capacitance of 835.7 F g-1 at 0.5 A g-1, an enhanced rate capability and excellent electrochemical stability with 93% retention after 10,000 cycles even at 10 A g-1. Moreover, a hybrid supercapacitor combined with YS-NiCo2O4 and graphene shows a high energy density of 34.7 Wh kg-1 at the power density of 395.0 W kg-1 at 0.5 A g-1, even at 20 A g-1, the hybrid supercapacitor still delivers the energy density of about 12.1 Wh kg-1 and the power density of 11697 W kg-1. The desirable performance of yolk-shelled NiCo2O4 suggests it to be a promising material as supercapacitor electrodes.

Multiplication in Egg Yolk and Survival in Egg Albumen of Genetically and Phenotypically Characterized Salmonella Enteritidis Strains.

PubMed

Gast, Richard K; Guard, Jean; Guraya, Rupa; Locatelli, Aude

2018-06-01

Prompt refrigeration of eggs to prevent the multiplication of Salmonella Enteritidis to high levels during storage is an important practice for reducing the risk of egg-transmitted human illness. The efficacy of egg refrigeration for achieving this goal depends on the interaction among the location of contamination, the ability of contaminant strains to survive or multiply, and the rate at which growth-restricting temperatures are attained. The present study assessed the significance of several characterized genetic and phenotypic properties for the capabilities of 10 Salmonella Enteritidis isolates to multiply rapidly in egg yolk and survive for several days in egg albumen during unrefrigerated (25°C) storage. The growth of small numbers of each Salmonella Enteritidis strain (approximately 10 1 CFU/mL) inoculated into egg yolk samples was determined after 6 and 24 h of incubation. The survival of larger numbers of Salmonella Enteritidis (approximately 10 5 CFU/mL) inoculated into albumen samples was determined at 24 and 96 h of incubation. In yolk, the inoculated Salmonella Enteritidis strains multiplied to mean levels of approximately 10 2.6 CFU/mL after 6 h of incubation and 10 8.3 CFU/mL after 24 h. In albumen, mean levels of approximately 10 4.6 CFU/mL Salmonella Enteritidis were maintained through 96 h. The concentrations of the various Salmonella strains after incubation in either yolk or albumen were distributed over relatively narrow ranges of values. Significant ( P < 0.01) differences observed among individual strains suggested that maintenance of the fimbrial gene sefD may have positive genetic selection value by improving fitness to grow inside egg yolk, whereas the antibiotic resistance gene bla TEM-1 tet(A) appeared to have negative genetic selection value by decreasing fitness to survive in egg albumen.

Comparing sugar type supplementation for cryopreservation of boar semen in egg yolk based extender.

PubMed

Malo, C; Gil, L; Gonzalez, N; Cano, R; de Blas, I; Espinosa, E

2010-08-01

Cryopreservation of boar semen is still considered suboptimal due to lower fertility when compared to fresh semen. The aim of this study was to evaluate the effects of the addition of different sugars (lactose, trehalose and glucose) on boar spermatozoa cryopreserved in an egg yolk based extender. Ejaculates were collected from a boar previously selected and semen samples were processed using the straw freezing procedure. In experiment 1, subsamples of semen were frozen in three different extenders: recommended lactose egg yolk extender (LEY); trehalose egg yolk extender (TEY) and glucose egg yolk extender (GEY). Sperm quality was assessed for motility, viability, acrosome integrity and hypoosmotic swelling test response upon collection, after freezing and thawing and then every hour for 3h. Results showed that total motility at 1 and 3h, progressive motility at 3h, positive hypoosmotic response at 2 and 3h and acrosome integrity at all times were significantly improved when trehalose was added to the extender. In experiment 2, sugar influence was also demonstrated in vitro fertilization. A total of 1691 oocytes were in vitro matured and inseminated with frozen-thawed sperm at 2000:1 sperm:oocyte ratio and coincubated for 6h. Presumptive zygotes were cultured in NCSU-23 medium to assess fertilization parameters and embryo development. Both penetration and monospermy rates were significantly higher for trehalose frozen semen. A significant increase was observed in efficiency and blastocyst formation rates from TEY to the other groups. Our results demonstrated that trehalose extender enhances spermatozoa viability and its in vitro fertilization parameters in boar ejaculates with good sperm freezability. Further studies are necessary to assess the impact of sugars on the entire population. (c) 2010 Elsevier Inc. All rights reserved.

Caspase-6 Activation in Familial Alzheimer Disease Brains Carrying Amyloid Precursor Protein, Presenilin I or Presenilin II Mutations

PubMed Central

Albrecht, Steffen; Bogdanovic, Nenad; Ghetti, Bernardino; Winblad, Bengt; LeBlanc, Andréa C.

2010-01-01

We previously demonstrated the activation of Caspase-6 in the hippocampus and cortex in cases of mild, moderate, severe and very severe Alzheimer disease (AD). To determine whether Caspase-6 is also activated in familial AD, we performed an immunohistochemical analysis of active Caspase-6 and Tau cleaved by Caspase-6 in temporal cortex and hippocampal tissue sections from cases of familial AD. The cases included 5 carrying the amyloid precursor protein K670N, M671L Swedish mutation, 1 carrying the amyloid precursor protein E693G Arctic mutation, 2 each carrying the Presenilin I M146V, F105L, A431E, V261F, Y115C mutations, and 1 with the Presenilin II N141I mutation. Active Caspase-6 immunoreactivity was found in all cases. Caspase-6 immunoreactivity was observed in neuritic plaques or cotton wool plaques in some cases, neuropil threads and neurofibrillary tangles. These results indicate that Caspase-6 is activated in familial forms of AD, as previously observed in sporadic forms. Since sporadic and familial AD cases have similar pathological features, these results support a fundamental role of Caspase-6 in the pathophysiology of both familial and sporadic AD. PMID:19915487

Amyloid precursor protein controls cholesterol turnover needed for neuronal activity

PubMed Central

Pierrot, Nathalie; Tyteca, Donatienne; D'auria, Ludovic; Dewachter, Ilse; Gailly, Philippe; Hendrickx, Aurélie; Tasiaux, Bernadette; Haylani, Laetitia El; Muls, Nathalie; N'Kuli, Francisca; Laquerrière, Annie; Demoulin, Jean-Baptiste; Campion, Dominique; Brion, Jean-Pierre; Courtoy, Pierre J; Kienlen-Campard, Pascal; Octave, Jean-Noël

2013-01-01

Perturbation of lipid metabolism favours progression of Alzheimer disease, in which processing of Amyloid Precursor Protein (APP) has important implications. APP cleavage is tightly regulated by cholesterol and APP fragments regulate lipid homeostasis. Here, we investigated whether up or down regulation of full-length APP expression affected neuronal lipid metabolism. Expression of APP decreased HMG-CoA reductase (HMGCR)-mediated cholesterol biosynthesis and SREBP mRNA levels, while its down regulation had opposite effects. APP and SREBP1 co-immunoprecipitated and co-localized in the Golgi. This interaction prevented Site-2 protease-mediated processing of SREBP1, leading to inhibition of transcription of its target genes. A GXXXG motif in APP sequence was critical for regulation of HMGCR expression. In astrocytes, APP and SREBP1 did not interact nor did APP affect cholesterol biosynthesis. Neuronal expression of APP decreased both HMGCR and cholesterol 24-hydroxylase mRNA levels and consequently cholesterol turnover, leading to inhibition of neuronal activity, which was rescued by geranylgeraniol, generated in the mevalonate pathway, in both APP expressing and mevastatin treated neurons. We conclude that APP controls cholesterol turnover needed for neuronal activity. PMID:23554170

Amyloid precursor protein at node of Ranvier modulates nodal formation

PubMed Central

Xu, De-En; Zhang, Wen-Min; Yang, Zara Zhuyun; Zhu, Hong-Mei; Yan, Ke; Li, Shao; Bagnard, Dominique; Dawe, Gavin S; Ma, Quan-Hong; Xiao, Zhi-Cheng

2014-01-01

Amyloid precursor protein (APP), commonly associated with Alzheimer disease, is upregulated and distributes evenly along the injured axons, and therefore, also known as a marker of demyelinating axonal injury and axonal degeneration. However, the physiological distribution and function of APP along myelinated axons was unknown. We report that APP aggregates at nodes of Ranvier (NOR) in the myelinated central nervous system (CNS) axons but not in the peripheral nervous system (PNS). At CNS NORs, APP expression co-localizes with tenascin-R and is flanked by juxtaparanodal potassium channel expression demonstrating that APP localized to NOR. In APP-knockout (KO) mice, nodal length is significantly increased, while sodium channels are still clustered at NORs. Moreover, APP KO and APP-overexpressing transgenic (APP TG) mice exhibited a decreased and an increased thickness of myelin in spinal cords, respectively, although the changes are limited in comparison to their littermate WT mice. The thickness of myelin in APP KO sciatic nerve also increased in comparison to that in WT mice. Our observations indicate that APP acts as a novel component at CNS NORs, modulating nodal formation and has minor effects in promoting myelination. PMID:25482638

Incorporation of Deoxyribonucleic Acid Precursors by T4 Deoxyribonucleic Acid-Protein Complexes Retained on Glass Fiber Filters

PubMed Central

Miller, Robert C.; Kozinski, Andrzej W.

1970-01-01

Bacteriophage T4 deoxyribonucleic acid (DNA)-protein complexes were retained preferentially on glass fiber filters. DNA polymerase activity in the complex was detected through the incorporation of 3H-labeled DNA precursors. The primer-product DNA hybridized with both phage and Escherichia coli DNA. Density labeling experiments showed that about 30% of incorporated 3H-deoxyadenosine triphosphate was found in DNA which hybridized with phage DNA; this DNA was found to be covalently attached to the primer DNA. PMID:5497903

[Separation and identification of red pigments in natural red yolk of duck's eggs by HPLC-MS-MS].

PubMed

Liu, Liangzhong; Zhang, Min; Peng, Guanghua; Wang, Haibin; Zhang, Shenghua

2004-05-01

The natural red yolk of duck's eggs is produced by the laying duck in the lake areas in southward of China. In the laying duck breeding areas such as Honghu, Jianli, Xiantao, Tianmen and Hanchuan citys in Hubei Province, the culturists are used to feeding fresh pondweeds to the laying ducks. The yolk of duck's eggs is natural red with the chrominance reaching up to and/or above RCF (Roche Yolk Color Fan) 15. The red pigment components of natural red yolk of duck's eggs were separated and identified by thin layer chromatography (TLC), high performance liquid chromatography-mass spectrometry-mass spectrometry (HPLC-MS-MS) and high resolution electron impact-mass spectrometry (EI-MS). Four isomers of red pigments were separated by HPLC on a RP-C18 column with methanol-water (99.5:0.5, v/v) as mobile phase. The lambda(max) of the four components were 482, 488, 496, 501 nm, respectively, and all of them were single peak on chromatogram. They had the same molecular mass (Mr = 562), and had the same fragment peaks of MS2 with rhodoxanthin. The molecular formula of red pigments was determined as C40H50O2 by high resolution EI-MS. The results indicate that the red pigment is rhodoxanthin, and they are all cis-isomers of rhodoxanthin.

A simple method for isolating chicken egg yolk immunoglobulin using effective delipidation solution and ammonium sulfate.

PubMed

Tong, Chenyao; Geng, Fang; He, Zhenjiao; Cai, Zhaoxia; Ma, Meihu

2015-01-01

Chicken egg yolk immunoglobulin (IgY) is a superior alternative to mammalian immunoglobulin. However, the practical application of IgY in research, diagnostics, and functional food is limited due to complex or time-consuming purification procedures. The objective of this study was to develop a simple, safe, large-scale separation method for IgY from egg yolk. Egg yolk was diluted with 6-fold delipidation solutions made of different types (pectin, λ-carrageenan, carboxymethylcellulose, methylcellulose, and dextran sulfate) and concentrations (0.01, 0.05, 0.1, 0.15, and 0.2%) of polysaccharides, respectively. The yolk solution was adjusted to pH 5.0, and then kept overnight at 4°C before being centrifuged at 4°C. The resulting supernatant was added to 35% (w/v) (NH4)2SO4 and then centrifuged. The precipitant, which contained IgY, was dissolved in distilled water and then dialyzed. SDS-PAGE and Western blotting were utilized to conduct qualitative analysis of IgY; high-performance liquid chromatography (HPLC) was used for quantitative analysis. The immunoreactivity of IgY was measured by ELISA. The results showed that yield, purity, and immunoreactivity varied with types and concentrations of polysaccharides. The optimal isolation of IgY for pectin, λ-carrageenan, dextran sulfate, and carboxymethylcellulose was at the concentration of 0.1%; for methylcellulose, optimal isolation was at 0.15%. The best results were obtained in the presence of 0.1% pectin. In this condition, yield and purity can reach 8.36 mg/mL egg yolk and 83.3%, respectively, and the negative effect of IgY on immunoreactivity can be minimized. The procedure of isolation was simplified to 2 steps with a higher yield of IgY, avoiding energy- and time-consuming methods. Therefore, the isolation condition under study has a great potential for food industry production of IgY on a large scale. © 2014 Poultry Science Association Inc.

Ruptured-yolk peritonitis and organochlorine residues in a royal tern

USGS Publications Warehouse

Blus, L.J.; Locke, L.N.; Stafford, C.J.

1977-01-01

Ruptured-yolk peritonitis was responsible for the death of a royal tern. Lodgment of eggs in the oviduct was probably due to reverse peristalsis brought about by breakage of the thin-shelled eggs and secondary bacterial infection. The thin shells were apparently not related to the low levels of DDE and other organochlorine pollutants found in tissues and egg contents.

Yolk hormones influence in ovo chemosensory learning, growth, and feeding behavior in domestic chicks.

PubMed

Bertin, Aline; Meurisse, Maryse; Arnould, Cécile; Leterrier, Christine; Constantin, Paul; Cornilleau, Fabien; Vaudin, Pascal; Burlot, Thierry; Delaveau, Joel; Rat, Christophe; Calandreau, Ludovic

2016-03-01

In this study, we assessed whether prenatal exposure to elevated yolk steroid hormones can influence in ovo chemosensory learning and the behavior of domestic chicks. We simulated a maternal environmental challenge by experimentally enhancing yolk progesterone, testosterone, and estradiol concentrations in hen eggs prior to incubation. The embryos from these hormones-treated eggs (HO) as well as sham embryos (O) that had received the vehicle-only were exposed to the odor of fish oil (menhaden) between embryonic Days 11 and 20. An additional group of control embryos (C) was not exposed to the odor. All chicks were tested following hatching for their feeding preferences between foods that were or were not odorized with the menhaden odor. In the 3-min choice tests, the behavior of O chicks differed significantly according to the type of food whereas C and HO chicks showed no preference between odorized and non-odorized food. Our result suggests weaker response in HO chicks. In addition, HO chicks showed impaired growth and reduced intake of an unfamiliar food on the 24-h time scale compared to controls. Our data suggest that embryonic exposure to increased yolk hormone levels can alter growth, chemosensory learning, and the development of feeding behaviors. © 2015 Wiley Periodicals, Inc.

Evolutionary implications of interspecific variation in a maternal effect: a meta-analysis of yolk testosterone response to competition

PubMed Central

Navara, Kristen J.

2016-01-01

Competition between conspecifics during the breeding season can result in behavioural and physiological programming of offspring via maternal effects. For birds, in which maternal effects are best studied, it has been claimed that exposure to increased competition causes greater deposition of testosterone into egg yolks, which creates faster growing, more aggressive offspring; such traits are thought to be beneficial for high-competition environments. Nevertheless, not all species show a positive relationship between competitive interactions and yolk testosterone, and an explanation for this interspecific variation is lacking. We here test if the magnitude and direction of maternal testosterone allocated to eggs in response to competition can be explained by life-history traits while accounting for phylogenetic relationships. We performed a meta-analysis relating effect size of yolk testosterone response to competition with species coloniality, nest type, parental effort and mating type. We found that effect size was moderated by coloniality and nest type; colonial species and those with open nests allocate less testosterone to eggs when in more competitive environments. Applying a life-history perspective helps contextualize studies showing little or negative responses of yolk testosterone to competition and improves our understanding of how variation in this maternal effect may have evolved. PMID:28018636

The early mature part of bacterial twin-arginine translocation (Tat) precursor proteins contributes to TatBC receptor binding.

PubMed

Ulfig, Agnes; Freudl, Roland

2018-05-11

The twin-arginine translocation (Tat) pathway transports folded proteins across bacterial membranes. Tat precursor proteins possess a conserved twin-arginine (RR) motif in their signal peptides that is involved in the binding of the proteins to the membrane-associated TatBC receptor complex. In addition, the hydrophobic region in the Tat signal peptides also contributes to TatBC binding, but whether regions beyond the signal-peptide cleavage site are involved in this process is unknown. Here, we analyzed the contribution of the early mature protein part of the Escherichia coli trimethylamine N -oxide reductase (TorA) to productive TatBC receptor binding. We identified substitutions in the 30 amino acids immediately following the TorA signal peptide (30aa-region) that restored export of a transport-defective TorA[KQ]-30aa-MalE precursor, in which the RR residues had been replaced by a lysine-glutamine pair. Some of these substitutions increased the hydrophobicity of the N-terminal part of the 30aa-region and thereby likely enhanced hydrophobic substrate-receptor interactions within the hydrophobic TatBC substrate-binding cavity. Another class of substitutions increased the positive net charge of the region's C-terminal part, presumably leading to strengthened electrostatic interactions between the mature substrate part and the cytoplasmic TatBC regions. Furthermore, we identified substitutions in the C-terminal domains of TatB following the transmembrane segment that restored transport of various transport-defective TorA-MalE derivatives. Some of these substitutions most likely affected the orientation or conformation of the flexible, carboxy-proximal helices of TatB. Therefore, we propose that a tight accommodation of the folded mature region by TatB contributes to productive binding of Tat substrates to TatBC. © 2018 Ulfig and Freudl.

Spider silk MASP1 and MASP2 proteins as carbon fiber precursors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lewis, Randolph V

The objective of this project is to develop an unconventional non-petroleum based carbon fiber precursor which has the potential to be produced in high yield and quantities. Methods will be developed to produce pilot-scale quantities of fibers from spider silk proteins with mechanical properties at least 75% that of the natural dragline silk fibers in tensile strength and elongations of less than 5%. The precursor fibers will be converted to carbon fibers, with a goal of >250Ksi strength and 1-2% elongation. Cost analysis will be performed and the process optimized. Task 1: Subtask 1. Protein production: We exceeded the go/more » no go milestone of 1.0g/L of one of the spider silk protein (MSp2) purified last FY and have now increased from 5L to 500L fermentations. We have made a series of changes to the purification protocol from the initial report last FY. These led to a reduction in the time needed for the purification and reduced the purification costs by nearly 90%. Subtask 2. Fiber spinning: The major focus has been to produce more material to send 24 fiber thread to ONRL. We are still developing the methodology to successfully spin 24 fiber yarns. This involves both the spinning dope solutions as well as the methods to keep the fibers from fusing during the post spin stretch. The second area of focus has been to standardize the spin dopes for making the fibers. We now know that the conductivity (indicative of salt remaining with the protein after purification) is an important factor in successful spinning as is the pH. We now know that we need to be below 600 uS conductivity and that the most effective pH is protein dependent. Subtask 3. Silkworm silk: We have found the transgenic silkworms made using gene replacement at the fibroin light chain instead of heavy chain as we did previously have a higher tensile strength. See figures below showing the curve for the top end of the cocoon fibers. This tensile strength is the same as the average for spider

Asymmetrical flow field-flow fractionation coupled with multiple detections: A complementary approach in the characterization of egg yolk plasma.

PubMed

Dou, Haiyang; Li, Yueqiu; Choi, Jaeyeong; Huo, Shuying; Ding, Liang; Shen, Shigang; Lee, Seungho

2016-09-23

The capability of asymmetrical flow field-flow fractionation (AF4) coupled with UV/VIS, multiangle light scattering (MALS) and quasi-elastic light scattering (QELS) (AF4-UV-MALS-QELS) for separation and characterization of egg yolk plasma was evaluated. The accuracy of hydrodynamic radius (Rh) obtained from QELS and AF4 theory (using both simplified and full expression of AF4 retention equations) was discussed. The conformation of low density lipoprotein (LDL) and its aggregates in egg yolk plasma was discussed based on the ratio of radius of gyration (Rg) to Rh together with the results from bio-transmission electron microscopy (Bio-TEM). The results indicate that the full retention equation is more relevant than simplified version for the Rh determination at high cross flow rate. The Rh from online QELS is reliable only at a specific range of sample concentration. The effect of programmed cross flow rate (linear and exponential decay) on the analysis of egg yolk plasma was also investigated. It was found that the use of an exponentially decaying cross flow rate not only reduces the AF4 analysis time of the egg yolk plasma, but also provides better resolution than the use of either a constant or linearly decaying cross flow rate. A combination of an exponentially decaying cross flow AF4-UV-MALS-QELS and the utilization of full retention equation was proved to be a useful method for the separation and characterization of egg yolk plasma. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of hatching egg characteristics, embryo development, yolk absorption, hatch window, and hatchability of Pekin Duck eggs of different weights.

PubMed

Ipek, A; Sozcu, A

2017-10-01

This study was carried out to determine the hatching egg characteristics, embryo development and yolk absorption during incubation, hatch window, and hatchability of Pekin duck eggs of different weights. A total of 960 hatching eggs was obtained from a breeder flock 35 to 36 wk of age. The eggs were classed into 3 weight categories: "light" (L; <75 g), "medium" (M; 76 to 82 g), and "heavy" (H; >83 g). The albumen weight was the highest in the heavy eggs, whereas the yolk weight was higher in the medium and heavy eggs. Egg breaking strength was the highest with a value of 2.5 kg/cm2 in light eggs, whereas the thinnest eggshell (0.3862 mm) was observed in heavy eggs. pH of albumen and yolk was similar and ranged from 8.8 to 8.9 and 5.9 to 6.0, respectively. On d 14 of incubation, yolk sac weight was found higher in the medium and heavy eggs. Additionally, the dry matter of the embryo and yolk sac differed among the egg weight groups during the incubation period. Interestingly, on d 25 of incubation, the embryo weight was higher in the light and heavy eggs (35.2 and 36.3 g, respectively) than in the medium eggs (29.8 g). These findings showed that embryo growth was affected by yolk absorption and dry matter accumulation. The hatchability of total and fertile eggs was lower for the heavy eggs than the light and medium eggs. The chick weight was 42.8, 48.4, and 54.9 g in light, medium, and heavy eggs, respectively. A percentage of 34.2, 36, and 31.6% of chicks from light, medium, and heavy eggs, hatched between 637 and 648 h, 39.6, 36.2, and 32.9% between 649 and 660 h, 26.2, 27.8, and 35.5% between 661 and 672 h of incubation, respectively. In conclusion, hatching egg quality, embryo development and yolk absorption during incubation, hatch window, and hatchability were affected by egg weight in Pekin ducks. © 2017 Poultry Science Association Inc.

Curcumin decreases amyloid-beta peptide levels by attenuating the maturation of amyloid-beta precursor protein.

PubMed

Zhang, Can; Browne, Andrew; Child, Daniel; Tanzi, Rudolph E

2010-09-10

Alzheimer disease (AD) is a devastating neurodegenerative disease with no cure. The pathogenesis of AD is believed to be driven primarily by amyloid-beta (Abeta), the principal component of senile plaques. Abeta is an approximately 4-kDa peptide generated via cleavage of the amyloid-beta precursor protein (APP). Curcumin is a compound in the widely used culinary spice, turmeric, which possesses potent and broad biological activities, including anti-inflammatory and antioxidant activities, chemopreventative effects, and effects on protein trafficking. Recent in vivo studies indicate that curcumin is able to reduce Abeta-related pathology in transgenic AD mouse models via unknown molecular mechanisms. Here, we investigated the effects of curcumin on Abeta levels and APP processing in various cell lines and mouse primary cortical neurons. We show for the first time that curcumin potently lowers Abeta levels by attenuating the maturation of APP in the secretory pathway. These data provide a mechanism of action for the ability of curcumin to attenuate amyloid-beta pathology.

Curcumin Decreases Amyloid-β Peptide Levels by Attenuating the Maturation of Amyloid-β Precursor Protein*

PubMed Central

Zhang, Can; Browne, Andrew; Child, Daniel; Tanzi, Rudolph E.

2010-01-01

Alzheimer disease (AD) is a devastating neurodegenerative disease with no cure. The pathogenesis of AD is believed to be driven primarily by amyloid-β (Aβ), the principal component of senile plaques. Aβ is an ∼4-kDa peptide generated via cleavage of the amyloid-β precursor protein (APP). Curcumin is a compound in the widely used culinary spice, turmeric, which possesses potent and broad biological activities, including anti-inflammatory and antioxidant activities, chemopreventative effects, and effects on protein trafficking. Recent in vivo studies indicate that curcumin is able to reduce Aβ-related pathology in transgenic AD mouse models via unknown molecular mechanisms. Here, we investigated the effects of curcumin on Aβ levels and APP processing in various cell lines and mouse primary cortical neurons. We show for the first time that curcumin potently lowers Aβ levels by attenuating the maturation of APP in the secretory pathway. These data provide a mechanism of action for the ability of curcumin to attenuate amyloid-β pathology. PMID:20622013

Lutein and zeaxanthin: Role as macular pigment and factors that control bioavailability from egg yolks and nanoemulsions

NASA Astrophysics Data System (ADS)

Vishwanathan, Rohini

Lutein and zeaxanthin, two oxygenated carotenoids, exclusively accumulate in the macula, protecting the underlying photoreceptors and retinal pigment epithelial cells from damaging blue radiation of sunlight. As macular pigment, lutein and zeaxanthin are also potent antioxidants protecting the vulnerable regions of retina from free radical injury. Oxidative stress and cumulative light damage play an important role in pathogenesis of age-related macular degeneration (AMD), the leading cause of vision loss in the elderly population. Antioxidant and lutein supplementation has been shown to decrease the risk and prevent the progression of AMD. The egg yolk is a highly bioavailable source of lutein and zeaxanthin and thus a possible contender for AMD prevention and treatment. Consumption of 2 egg yolks/d for 5 weeks was shown herein to significantly increase serum lutein and zeaxanthin concentration and clinically improve macular pigment concentrations at 0.5° retinal eccentricity in an older adult population taking cholesterol-lowering statins. Four egg yolks/d not only raised serum lutein and zeaxanthin significantly but also macular pigment densities at 0.25°, 0.5° and 1° retinal eccentricity. A positive outcome of the 2 egg yolk consumption was the significant increase in serum HDL-C with a tendency of serum LDL-C to decrease, although not significantly. Four egg yolks/d seemed to cross the threshold for dietary cholesterol tolerance as serum LDL-C tended to increase, although not significantly, despite the significant increase in serum HDL-C. There is a strong possibility that greater build up of lutein and zeaxanthin in the macula may have been observed with 2 egg yolks/d if the intervention period was longer than 5 weeks. Addition of up to 2 eggs a day to the diet is suggested to benefit an older adult population, especially those who are already taking cholesterol-lowering statins by (a) building their macular pigment and possibly protect against AMD and (b

[Mutations of amyloid precursor protein in early-onset familial Alzheimer's disease].

PubMed

Naruse, S; Tsuji, S; Miyatake, T

1992-09-01

Genetic linkage studies of familial Alzheimer's disease (FAD) have suggested that some form of early-onset FAD is linked to proximal long arm of chromosome 21. It has been also suggested that some form of late-onset FAD is linked to long arm of chromosome 19. Goate et al have identified a mis-sense mutation (Val to Ile) in exon 17 of the amyloid precursor protein (APP) gene in 2 of 16 early-onset FAD families, and have shown that the FAD locus in an FAD family is tightly linked to the mis-sense mutation. To determine if the mis-sense mutation is observed in different ethnic origine, we have studied some early-onset FAD families. Two early-onset FAD families showed the existence of the mutation. As the mutation has been identified in different ethnic origine and the mutation has not been observed in normal individuals, it strengthen hypothesis that the mutation is pathogenic. Recently, Val to Phe and Val to Gly mutations have been also identified at the same codon (Codon 717) of the APP gene.

The amyloid precursor protein locus and very-late-onset Alzheimer disease.

PubMed

Olson, J M; Goddard, K A; Dudek, D M

2001-10-01

Although mutations in the amyloid-beta precursor protein (APP) gene are known to confer high risk of Alzheimer disease (AD) to a small percentage of families in which it has early onset, convincing evidence of a major role for the APP locus in late-onset AD has not been forthcoming. In this report, we have used a covariate-based affected-sib-pair linkage method to analyze the chromosome 21 clinical and genetic data obtained on affected sibships by the National Institute of Mental Health Alzheimer Disease Genetics Initiative. The baseline model (without covariates) gave a LOD score of 0.02, which increases to 1.43 when covariates representing the additive effects of E2 and E4 are added. Larger increases in LOD scores were found when age at last examination/death (LOD score 5.54; P=.000002) or age at onset plus disease duration (LOD score 5.63; P=.000006) were included in the linkage model. We conclude that the APP locus may predispose to AD in the very elderly.

The proteolytic processing site of the precursor of lysyl oxidase.

PubMed Central

Cronshaw, A D; Fothergill-Gilmore, L A; Hulmes, D J

1995-01-01

The precise cleavage site of the N-terminal propeptide region of the precursor of lysyl oxidase has not yet been established, due to N-terminal blocking of the mature protein. Using a combination of peptide fragmentation, amino acid sequencing, time-of-flight m.s. and partial chemical unblocking procedures, it is shown that the mature form of lysyl oxidase begins at residue Asp-169 of the precursor protein (numbered according to the human sequence). The cleavage site is 28 residues to the C-terminal side of the site previously suggested on the basis of apparant molecular mass by SDS/PAGE, with the consequence that the two putative, N-linked glycosylation sites and the position of the Arg/Gln sequence polymorphism are now all in the precursor region. PMID:7864821

The effect of dietary conjugated linoleic acid on egg yolk fatty acids and hatchability in Japanese quail.

PubMed

Aydin, R; Cook, M E

2004-12-01

Conjugated linoleic acid (CLA) increased the ratio of saturated fatty acids to monounsaturated fatty acids in yolk and caused embryo mortality. Our preliminary studies showed that CLA had less of an effect on hatchability of quail than chickens. Hence, the objective was to determine the effects of dietary CLA on quail egg fatty acid content and hatchability. Eight male-female Japanese quail pairs per group were randomly assigned to diets containing 0 (canola oil; CO), 0.25, 0.5, 1, 2, or 3% CLA for 8 wk. Eggs were collected, held at 15 degrees C for 24 h, and then incubated. Three eggs from each group were collected for fatty acid analysis on the 45th day. At the end of the 8 wk, all quail were euthanized. Liver samples from female quail were obtained for fatty acid analysis. Diet containing 3, 2, or 1% CLA caused 100% embryo mortality after 6, 10, or 12 d of feeding, whereas overall hatchabilities in groups 0, 0.25, and 0.5 were 84, 86, and 64%, respectively. As the dietary CLA increased, egg and hepatic CLA increased, C16:0 increased and C16:1(n-7) and C18:1(n-9) decreased, whereas C18:0 remained unchanged. Diets containing 1, 2, or 3% CLA decreased the C20:4(n-6) levels in yolk (significantly) and liver (inconsistently) lipids. Yolk CLA levels from 0, 0.25, 0.5, 1, 2, and 3% CLA were 0.31, 0.90, 1.48, 2.44, 5.88, and 11.2%, respectively. The ratios of C16:0/C16:1(n-7) in yolks from groups fed 0, 0.25, 0.5, 1, 2, or 3% CLA were 8.2, 16.3, 20.4, 24.6, 26.1, and 28.6, respectively. The ratios of C18:0/C18:1(n-9) in yolks from hens fed 0, 0.25, 0.5, 1, 2, or 3% CLA were 0.28, 0.40, 0.48, 0.49, 0.69, and 0.83, respectively. Quail fed 0.25% CLA had increased egg size, whereas quail fed 2 or 3% had reduced egg size compared with those fed CO. Liver sizes (%) in all of the groups were increased, except for the group fed 0.25% CLA. These data suggest that CLA may affect hatchability possibly by changing the fatty acid composition of the yolk.

Herbal adaptogens combined with protein fractions from bovine colostrum and hen egg yolk reduce liver TNF-α expression and protein carbonylation in Western diet feeding in rats

PubMed Central

2014-01-01

Background We examined if a purported anti-inflammatory supplement (AF) abrogated Western-diet (WD)-induced liver pathology in rats. AF contained: 1) protein concentrates from bovine colostrum and avian egg yolk; 2) herbal adaptogens and antioxidants; and 3) acetyl-L-carnitine. Methods Nine month-old male Brown Norway rats were allowed ad libitum access to WD for 41–43 days and randomly assigned to WD + AF feeding twice daily for the last 31–33 days (n = 8), or WD and water-placebo feeding twice daily for the last 31–33 days (n = 8). Rats fed a low-fat/low-sucrose diet (CTL, n = 6) for 41–43 days and administered a water-placebo twice daily for the last 31–33 days were also studied. Twenty-four hours following the last gavage-feed, liver samples were analyzed for: a) select mRNAs (via RT-PCR) as well as genome-wide mRNA expression patterns (via RNA-seq); b) lipid deposition; and, c) protein carbonyl and total antioxidant capacity (TAC). Serum was also examined for TAC, 8-isoprostane and clinical chemistry markers. Results WD + AF rats experienced a reduction in liver Tnf-α mRNA (-2.8-fold, p < 0.01). Serum and liver TAC was lower in WD + AF versus WD and CTL rats (p < 0.05), likely due to exogenous antioxidant ingredients provided through AF as evidenced by a tendency for mitochondrial SOD2 mRNA to increase in WD + AF versus CTL rats (p = 0.07). Liver fat deposition nor liver protein carbonyl content differed between WD + AF versus WD rats, although liver protein carbonyls tended to be lower in WD + AF versus CTL rats (p = 0.08). RNA-seq revealed that 19 liver mRNAs differed between WD + AF versus WD when both groups were compared with CTL rats (+/- 1.5-fold, p < 0.01). Bioinformatics suggest that AF prevented WD-induced alterations in select genes related to the transport and metabolism of carbohydrates in favor of select genes related to lipid transport and metabolism. Finally, serum clinical

Effects of dietary supplementation with Gynura procumbens (Merr.) on egg yolk cholesterol, excreta microflora and laying hen performance.

PubMed

Lokhande, A; Ingale, S L; Lee, S H; Sen, S; Khong, C; Chae, B J; Kwon, I K

2014-01-01

Abstract 1. The present study investigated the effects of dietary supplementation with Gynura procumbens on egg yolk and serum cholesterol and triglycerides, excreta microflora, laying performance and egg quality. 2. A total of 160 Hy-Line Brown layers (45 weeks old) were randomly assigned into 4 treatments on the basis of laying performance. Each treatment had 4 replicates with 10 birds each. 3. Dietary treatments were basal diet supplemented with 0 (control), 2.5, 5.0 and 7.5 g/kg diet G. procumbens during 56-d feeding period. 4. Serum (d 21, 42 and 56) and egg yolk (d 28, 42 and 56) cholesterol and triglycerides concentrations were linearly reduced with increasing dietary concentrations of G. procumbens. 5. Increasing dietary concentrations of G. procumbens linearly reduced the excreta total anaerobic bacteria (d 28), Clostridium sp. and Escherichia coli (d 28 and 56) populations. 6. Overall egg production and egg mass were linearly increased, and overall feed efficiency was linearly improved with increase in dietary G. procumbens. 7. Dietary increasing concentrations of G. procumbens linearly improved egg yolk colour (d 28 and 56) and breaking strength of eggs (d 56). 8. The results obtained in the present experiment indicate that dietary supplementation with G. procumbens could reduce the egg yolk cholesterol, suppresses harmful excreta microflora and improves layers performance.

Influence of sumac (Rhus Coriaria L.) and ginger (Zingiber officinale) on egg yolk fatty acid, cholesterol and blood parameters in laying hens.

PubMed

Gurbuz, Y; Salih, Y G

2017-12-01

The aim of the study was to evaluate the potential effect of different levels of sumac (Rhus coriaria L.) seed powder and ginger (Zingiber officinale) root powder on egg yolk fatty acid composition, blood/yolk cholesterol in laying hen. A total of 63 (ATAK-S: Domestic Turkish Laying Hens) laying hens (average weight: 1470 g each hen, 25-weeks of age) were assigned to seven treatment diets including sumac seed (S) and ginger root powder (G) at 0 g/kg (control), 10 g/kg (S1), 20 g/kg (S2), and 30 g/kg (S3); 10 g/kg (G1), 20 g/kg (G2), or 30 g/kg in rations respectively, for 8 weeks. After a two-week adaptation period to cages, the hens were allocated to 7 groups with 9 replicates of 1 hen in per cage each. The replications were allotted equally into the upper and lower cages to minimize the effects of cage level. In this study, egg yolk cholesterol had a decrease (p <0.05) in supplemented diet( sumac seed and ginger root powder). Fatty acid content in yolk; saturated fatty acid, monounsaturated fatty acids, polyunsaturated fatty acids and rate of n6/n3 were not significant (p <0.05). However, dietary supplementation with sumac and ginger powder reduced and yolk/blood cholesterol concentrations in laying hens. Supplementation of sumac and ginger affected on HDL, there was found a significant effect (p < 0.05) in treatment groups. Moreover, LDL positively decreased in all treatment groups compared with the control group. The findings of this study suggested that feeding sumac and ginger tend to be decreasing cholesterol levels in both yolk and blood on laying hens. It can be concluded that ginger root and sumac seed powder can be used as an effective feed additive to improve fatty acid composition and yolk and blood cholesterol in ATAK-S laying hens. Journal of Animal Physiology and Animal Nutrition © 2017 Blackwell Verlag GmbH.

Vitellogenesis in Bufo arenarum: Identification, characterization and immunolocalization of high molecular mass lipovitellin during oogenesis

PubMed Central

O’Brien, Emma D.; Salicioni, Ana M.; Cabada, Marcelo O.; Arranz, Silvia E.

2009-01-01

Vitellogenin (Vtg), a large lipoglycophosphoprotein, is the most important precursor of the yolk proteins, and the major source of nutrients for the developing embryo in oviparous species. After its uptake by the oocytes, Vtg is converted into lipovitellins (high and light) and phosvitin, which are deposited into crystalline yolk platelets. We describe here the presence of two high molecular mass lipovitellins isoforms in Bufo arenarum mature oocytes with masses of 113 and 100 kDa, respectively. The amino acid sequence analysis of p113 and p100 peptides showed a high sequence homology between both polypeptides and the complete reported sequences of Xenopus laevis vitellogenin. Using specific antibodies, we determined that the Vtg uptake begins early during oogenesis, at the previtellogenic stage, and continues until oocytes have reached their mature status. In addition, we found that large endocytic vesicles mediate Vtg uptake in stage I oocytes, and that the size of the endocytic vesicles declines with oogenesis progression. In terms of the Vtg protein trafficking, we detected the Vtg precursor (190 kDa) in the liver of estradiol-injected females. Finally, we propose a subclassification of B. arenarum stage-II oocytes into three physiologically and morphologically distinct periods (early, mid and late). PMID:19932187

Vitellogenesis in Bufo arenarum: identification, characterization and immunolocalization of high molecular mass lipovitellin during oogenesis.

PubMed

O'Brien, Emma D; Salicioni, Ana M; Cabada, Marcelo O; Arranz, Silvia E

2010-03-01

Vitellogenin (Vtg), a large lipoglycophosphoprotein, is the most important precursor of the yolk proteins, and the major source of nutrients for the developing embryo in oviparous species. After its uptake by the oocytes, Vtg is converted into lipovitellins (high and light) and phosvitin, which are deposited into crystalline yolk platelets. We describe here the presence of two high molecular mass lipovitellin isoforms in Bufo arenarum mature oocytes with masses of 113 and 100 kDa, respectively. The amino acid sequence analysis of p113 and p100 peptides showed a high sequence homology between both polypeptides and the complete reported sequences of Xenopus laevis vitellogenin. Using specific antibodies, we determined that the Vtg uptake begins early during oogenesis, at the previtellogenic stage, and continues until oocytes have reached their mature status. In addition, we found that large endocytic vesicles mediate Vtg uptake in stage I oocytes, and that the size of the endocytic vesicles declines with oogenesis progression. In terms of the Vtg protein trafficking, we detected the Vtg precursor (190 kDa) in the liver of estradiol-injected females. Finally, we propose a subclassification of B. arenarum stage II oocytes into three physiologically and morphologically distinct periods (early, mid and late). 2009 Elsevier Inc. All rights reserved.

Amyloid precursor protein mRNA levels in Alzheimer's disease brain.

PubMed

Preece, Paul; Virley, David J; Costandi, Moheb; Coombes, Robert; Moss, Stephen J; Mudge, Anne W; Jazin, Elena; Cairns, Nigel J

2004-03-17

Insoluble beta-amyloid deposits in Alzheimer's disease (AD) brain are proteolytically derived from the membrane bound amyloid precursor protein (APP). The APP gene is differentially spliced to produce isoforms that can be classified into those containing a Kunitz-type serine protease inhibitor domain (K(+), APP(751), APP(770), APRP(365) and APRP(563)), and those without (K(-), APP(695) and APP(714)). Given the hypothesis that Abeta is a result of aberrant catabolism of APP, differential expression of mRNA isoforms containing protease inhibitors might play an active role in the pathology of AD. We took 513 cerebral cortex samples from 90 AD and 81 control brains and quantified the mRNA isoforms of APP with TaqMan real-time RT-PCR. After adjustment for age at death, brain pH and gender we found a change in the ratio of KPI(+) to KPI(-) mRNA isoforms of APP. Three separate probes, designed to recognise only KPI(+) mRNA species, gave increases of between 28% and 50% in AD brains relative to controls (p=0.002). There was no change in the mRNA levels of KPI-(APP 695) (p=0.898). Therefore, whilst KPI-mRNA levels remained stable the KPI(+) species increased specifically in the AD brains.

Precursor-product discrimination by La protein during tRNA metabolism

PubMed Central

Bayfield, Mark A.; Maraia, Richard J.

2009-01-01

SUMMARY La proteins bind pre-tRNAs at their UUU-3'OH ends, facilitating their maturation. While the mechanism by which La binds pre-tRNA 3' trailers is known, the function of the RNA-binding β-sheet surface of RRM1 is unknown. How La dissociates from UUU-3'OH-containing trailers after 3' processing is also unknown. La preferentially binds pre-tRNAs over processed tRNAs or 3' trailer products through coupled use of two sites: one on the La motif and another on the RRM1 β surface that binds elsewhere on tRNA. Two sites provide stable pre-tRNA binding while processed tRNA and 3' trailer are released from their single sites relatively fast. RRM1 loop-3 mutations decrease affinity for pre-tRNA and tRNA but not UUU-3'OH trailer, and impair tRNA maturation in vivo. We propose that RRM1 functions in activities that are more complex than UUU-3'OH binding. Accordingly, the RRM1 mutations also impair a RNA chaperone activity of La. The results suggest how La distinguishes precursor from product RNAs, allowing it to recycle onto a new pre-tRNA. PMID:19287396

Precursor-product discrimination by La protein during tRNA metabolism.

PubMed

Bayfield, Mark A; Maraia, Richard J

2009-04-01

La proteins bind pre-tRNAs at their UUU-3'OH ends, facilitating their maturation. Although the mechanism by which La binds pre-tRNA 3' trailers is known, the function of the RNA binding beta-sheet surface of the RNA-recognition motif (RRM1) is unknown. How La dissociates from UUU-3'OH-containing trailers after 3' processing is also unknown. Here we show that La preferentially binds pre-tRNAs over processed tRNAs or 3' trailer products through coupled use of two sites: one on the La motif and another on the RRM1 beta-surface that binds elsewhere on tRNA. Two sites provide stable pre-tRNA binding, whereas the processed tRNA and 3' trailer are released from their single sites relatively fast. RRM1 loop-3 mutations decrease affinity for pre-tRNA and tRNA, but not for the UUU-3'OH trailer, and impair tRNA maturation in vivo. We propose that RRM1 functions in activities that are more complex than UUU-3'OH binding. Accordingly, the RRM1 mutations also impair an RNA chaperone activity of La. The results suggest how La distinguishes precursor from product RNAs, allowing it to recycle onto a new pre-tRNA.

Multi-dimensional construction of a novel active yolk@conductive shell nanofiber web as a self-standing anode for high-performance lithium-ion batteries

NASA Astrophysics Data System (ADS)

Liu, Hao; Chen, Luyi; Liang, Yeru; Fu, Ruowen; Wu, Dingcai

2015-11-01

A novel active yolk@conductive shell nanofiber web with a unique synergistic advantage of various hierarchical nanodimensional objects including the 0D monodisperse SiO2 yolks, the 1D continuous carbon shell and the 3D interconnected non-woven fabric web has been developed by an innovative multi-dimensional construction method, and thus demonstrates excellent electrochemical properties as a self-standing LIB anode.A novel active yolk@conductive shell nanofiber web with a unique synergistic advantage of various hierarchical nanodimensional objects including the 0D monodisperse SiO2 yolks, the 1D continuous carbon shell and the 3D interconnected non-woven fabric web has been developed by an innovative multi-dimensional construction method, and thus demonstrates excellent electrochemical properties as a self-standing LIB anode. Electronic supplementary information (ESI) available: Experimental details and additional information about material characterization. See DOI: 10.1039/c5nr06531c

Development of blood-yolk-polymyxin B-trimethoprim agar for the enumeration of Bacillus cereus in various foods.

PubMed

Kim, Dong-Hyeon; Kim, Hyunsook; Chon, Jung-Whan; Moon, Jin-San; Song, Kwang-Young; Seo, Kun-Ho

2013-07-15

Blood-yolk-polymyxin B-trimethoprim agar (BYPTA) was developed by the addition of egg yolk, laked horse blood, sodium pyruvate, polymyxin B, and trimethoprim, and compared with mannitol-yolk-polymyxin B agar (MYPA) for the isolation and enumeration of Bacillus cereus (B. cereus) in pure culture and various food samples. In pure culture, there was no statistical difference (p>0.05) between the recoverability and sensitivity of MYPA and BYPTA, whereas BYPTA exhibited higher specificity (p<0.05). To evaluate BYPTA agar with food samples, B. cereus was experimentally spiked into six types of foods, triangle kimbab, sandwich, misugaru, Saengsik, red pepper powder, and soybean paste. No statistical difference was observed in recoverability (p>0.05) between MYPA and BYPTA in all tested foods, whereas BYPTA exhibited higher selectivity than MYPA, especially in foods with high background microflora, such as Saengsik, red pepper powder, and soybean paste. The newly developed selective medium BYPTA could be a useful enumeration tool to assess the level of B. cereus in foods, particularly with high background microflora. Copyright © 2013 Elsevier B.V. All rights reserved.

Passive Immune-Protection of Litopenaeus vannamei against Vibrio harveyi and Vibrio parahaemolyticus Infections with Anti-Vibrio Egg Yolk (IgY)-Encapsulated Feed

PubMed Central

Gao, Xiaojian; Zhang, Xiaojun; Lin, Li; Yao, Dongrui; Sun, Jingjing; Du, Xuedi; Li, Xiumei; Zhang, Yue

2016-01-01

Vibrio spp. are major causes of mortality in white shrimp (Litopenaeus vannamei) which is lacking adaptive immunity. Passive immunization with a specific egg yolk antibody (IgY) is a potential method for the protection of shrimp against vibriosis. In this study, immune effects of the specific egg yolk powders (IgY) against both V. harveyi and V. parahaemolyticus on white shrimp were evaluated. The egg yolk powders against V. harveyi and V. parahaemolyticus for passive immunization of white shrimp were prepared, while a tube agglutination assay and an indirect enzyme-linked immunosorbent assay (ELISA) were used for detection of IgY titer. Anti-Vibrio egg yolk was encapsulated by β-cyclodextrin, which could keep the activity of the antibody in the gastrointestinal tract of shrimp. The results showed that the anti-Vibrio egg powders had an inhibiting effect on V. harveyi and V. parahaemolyticus in vitro. Lower mortality of infected zoeae, mysis, and postlarva was observed in groups fed with anti-Vibrio egg powders, compared with those fed with normal egg powders. The bacterial load in postlarva fed with specific egg powders in seeding ponds was significantly lower than those fed with normal egg powders in seeding ponds. These results show that passive immunization by oral administration with specific egg yolk powders (IgY) may provide a valuable protection of vibrio infections in white shrimp. PMID:27196895

Glycosylphosphatidylinositol membrane anchors in Saccharomyces cerevisiae: absence of ceramides from complete precursor glycolipids.

PubMed Central

Sipos, G; Puoti, A; Conzelmann, A

1994-01-01

Glycosylphosphatidylinositol (GPI) anchoring of membrane proteins occurs through two distinct steps, namely the assembly of a precursor glycolipid and its subsequent transfer onto newly synthesized proteins. To analyze the structure of the yeast precursor glycolipid we made use of the pmi40 mutant that incorporates very high amounts of [3H]mannose. Two very polar [3H]mannose-labeled glycolipids named CP1 and CP2 qualified as GPI precursor lipids since their carbohydrate head group, Man alpha 1,2(X-->PO4-->6)Man alpha 1,2Man alpha 1,6Man alpha-GlcN-inositol (with X most likely being ethanolamine) comprises the core structure which is common to all GPI anchors described so far. CP1 predominates in cells grown at 24 degrees C whereas CP2 is induced by stress conditions. The apparent structural identity of the head groups suggests that CP1 and CP2 contain different lipid moieties. The lipid moieties of both CP1 and CP2 can be removed by mild alkaline hydrolysis although the protein-bound GPI anchors made by the pmi40 cells under identical labeling conditions contain mild base resistant ceramides. These findings imply that the ceramide moiety found on the majority of yeast GPI anchored proteins is added through a lipid remodeling step that occurs after the addition of the GPI precursor glycolipids to proteins. Images PMID:8026463

Protection Efficacy of Multivalent Egg Yolk Immunoglobulin against Eimeria tenella Infection in Chickens

PubMed Central

Xu, JJ; Ren, CZ; Wang, SS; Liu, DD; Cao, LQ; Tao, JP

2013-01-01

Background To control avian coccidiosis with drug-independent strategy effectively and safely, multivalent hyperimmune egg yolk immunoglobulin (IgY) was prepared and its ability to protect against Eimeria tenella infection was evaluated. Methods Hens were orally immunized with live oocysts of 5 species of Eimeria for six times, antibody titers in serum and yolk were monitored by indirect enzyme-linked immunosorbent assay. The specific IgY was isolated, purified and lyophilized. IgY powder was orally administrated as dietary supplement in newly hatched chicks at various dosages. Birds were orally challenged with 10000 sporulated oocysts of E. tenella at 10 days of age, weighed and killed at 8 days post challenge, and the protective effect was assessed. Results The averge yeid of IgY was 9.2 mg/ml yolk, the antibody titer of IgY reached to 1:163840 per mg with the purity up to 98%. Chickens fed IgY resulted in reduced mortality, increased body weight gain (BWG), reduced oocyst shedding, reduced caecal lesion score and increased anti-coccidial index. In terms of BWG and caecal lesion, IgY significantly enhanced the resistance of bird at ≥ 0.05% of IgY in the diet when compared with the challenged control group (P<0.05). No significant difference was observed at dosage ≥ 0.5% and 1.0% when BWG and caecal lesion were compared with the sodium salinomycin control group, respectively (P>0.05). Conclusion Supplementing newly hatched chicks with Eimeria-specific IgY represents a promising strategy to prevent avian coccidiosis. PMID:24454440

One precursor, three apolipoproteins: the relationship between two crustacean lipoproteins, the large discoidal lipoprotein and the high density lipoprotein/β-glucan binding protein.

PubMed

Stieb, Stefanie; Roth, Ziv; Dal Magro, Christina; Fischer, Sabine; Butz, Eric; Sagi, Amir; Khalaila, Isam; Lieb, Bernhard; Schenk, Sven; Hoeger, Ulrich

2014-12-01

The novel discoidal lipoprotein (dLp) recently detected in the crayfish, differs from other crustacean lipoproteins in its large size, apoprotein composition and high lipid binding capacity, We identified the dLp sequence by transcriptome analyses of the hepatopancreas and mass spectrometry. Further de novo assembly of the NGS data followed by BLAST searches using the sequence of the high density lipoprotein/1-glucan binding protein (HDL-BGBP) of Astacus leptodactylus as query revealed a putative precursor molecule with an open reading frame of 14.7 kb and a deduced primary structure of 4889 amino acids. The presence of an N-terminal lipid bind- ing domain and a DUF 1943 domain suggests the relationship with the large lipid transfer proteins. Two-putative dibasic furin cleavage sites were identified bordering the sequence of the HDL-BGBP. When subjected to mass spectroscopic analyses, tryptic peptides of the large apoprotein of dLp matched the N-terminal part of the precursor, while the peptides obtained for its small apoprotein matched the C-terminal part. Repeating the analysis in the prawn Macrobrachium rosenbergii revealed a similar protein with identical domain architecture suggesting that our findings do not represent an isolated instance. Our results indicate that the above three apolipoproteins (i.e HDL-BGBP and both the large and the small subunit of dLp) are translated as a large precursor. Cleavage at the furin type sites releases two subunits forming a heterodimeric dLP particle, while the remaining part forms an HDL-BGBP whose relationship with other lipoproteins as well as specific functions are yet to be elucidated.

Interaction of the amyloid precursor protein-like protein 1 (APLP1) E2 domain with heparan sulfate involves two distinct binding modes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dahms, Sven O., E-mail: sdahms@fli-leibniz.de; Mayer, Magnus C.; Miltenyi Biotec GmbH, Robert-Koch-Strasse 1, 17166 Teterow

2015-03-01

Two X-ray structures of APLP1 E2 with and without a heparin dodecasaccharide are presented, revealing two distinct binding modes of the protein to heparan sulfate. The data provide a mechanistic explanation of how APP-like proteins bind to heparan sulfates and how they specifically recognize nonreducing structures of heparan sulfates. Beyond the pathology of Alzheimer’s disease, the members of the amyloid precursor protein (APP) family are essential for neuronal development and cell homeostasis in mammals. APP and its paralogues APP-like protein 1 (APLP1) and APP-like protein 2 (APLP2) contain the highly conserved heparan sulfate (HS) binding domain E2, which effects variousmore » (patho)physiological functions. Here, two crystal structures of the E2 domain of APLP1 are presented in the apo form and in complex with a heparin dodecasaccharide at 2.5 Å resolution. The apo structure of APLP1 E2 revealed an unfolded and hence flexible N-terminal helix αA. The (APLP1 E2){sub 2}–(heparin){sub 2} complex structure revealed two distinct binding modes, with APLP1 E2 explicitly recognizing the heparin terminus but also interacting with a continuous heparin chain. The latter only requires a certain register of the sugar moieties that fits to a positively charged surface patch and contributes to the general heparin-binding capability of APP-family proteins. Terminal binding of APLP1 E2 to heparin specifically involves a structure of the nonreducing end that is very similar to heparanase-processed HS chains. These data reveal a conserved mechanism for the binding of APP-family proteins to HS and imply a specific regulatory role of HS modifications in the biology of APP and APP-like proteins.« less

Cleavage of amyloid precursor protein by an archaeal presenilin homologue PSH

PubMed Central

Dang, Shangyu; Wu, Shenjie; Wang, Jiawei; Li, Hongbo; Huang, Min; He, Wei; Li, Yue-Ming; Wong, Catherine C. L.; Shi, Yigong

2015-01-01

Aberrant cleavage of amyloid precursor protein (APP) by γ-secretase contributes to the development of Alzheimer’s disease. More than 200 disease-derived mutations have been identified in presenilin (the catalytic subunit of γ-secretase), making modulation of γ-secretase activity a potentially attractive therapeutic opportunity. Unfortunately, the technical challenges in dealing with intact γ-secretase have hindered discovery of modulators and demand a convenient substitute approach. Here we report that, similar to γ-secretase, the archaeal presenilin homolog PSH faithfully processes the substrate APP C99 into Aβ42, Aβ40, and Aβ38. The molar ratio of the cleavage products Aβ42 over Aβ40 by PSH is nearly identical to that by γ-secretase. The proteolytic activity of PSH is specifically suppressed by presenilin-specific inhibitors. Known modulators of γ-secretase also modulate PSH similarly in terms of the Aβ42/Aβ40 ratio. Structural analysis reveals association of a known γ-secretase inhibitor with PSH between its two catalytic aspartate residues. These findings identify PSH as a surrogate protease for the screening of agents that may regulate the protease activity and the cleavage preference of γ-secretase. PMID:25733893

Epigenetic Induction of EGR-1 Expression by the Amyloid Precursor Protein during Exposure to Novelty

PubMed Central

Hendrickx, Aurélie; Pierrot, Nathalie; Tasiaux, Bernadette; Schakman, Olivier; Brion, Jean-Pierre; Kienlen-Campard, Pascal; De Smet, Charles; Octave, Jean-Noël

2013-01-01

Following transcriptome comparison of primary cultures isolated from brain of mice expressing or not the amyloid precursor protein APP, we found transcription of the EGR-1 gene to be regulated by APP. In primary cultures of cortical neurons, APP significantly down regulated EGR-1 expression at both mRNA and protein levels in a γ-secretase independent manner. The intracellular domain of APP did not interact with EGR-1 gene promoter, but enrichment of acetylated histone H4 at the EGR-1 promoter region was measured in APP-/- neurons, as well as in brain of APP-/- mice, in which increase in EGR-1 expression was also measured. These results argue for an important function of APP in the epigenetic regulation of EGR-1 gene transcription both in vitro and in vivo. In APP-/- mice, constitutive overexpression of EGR-1 in brain impaired epigenetic induction of this early transcriptional regulator during exposure to novelty. Altogether, these results indicate an important function of APP in the epigenetic regulation of the transcription of EGR-1, known to be important for memory formation. PMID:24066134

Effects of dietary fats on egg quality and lipid parameters in serum and yolks of Shan Partridge Duck.

PubMed

Du, Xue; Liu, Yali; Lu, Lizhi; Wang, Weiqun; Zeng, Tao; Tian, Yong; Xu, Xiaoqin; Shen, Jianliang; Niu, Dong; Lu, Yingru

2017-05-01

The effects of different dietary fats with variable levels of polyunsaturated fatty acids (PUFAs) on egg quality of Shan Partridge Duck, serum, and yolk lipid parameters were examined in this study. A flock of 585 optimal produced ducks were selected and diets enriched with 0.5%, 1%, or 2% fish oil (F)/flaxseed oil (FL)/rapeseed oil (R)/tallow (T) plus basal diet were supplied through a 28-d period. Supplemental fat source and fat level had no effects on egg qualities. Proportions of yolk total cholesterol (TC), saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) were reduced (P < 0.001), while polyunsaturated fatty acids (PUFAs), ω-6 polyunsaturated fatty acids (n-6 PUFAs), ω-3 polyunsaturated fatty acids (n-3 PUFAs), Docosahexaenoic Acid (DHA), and Eicosapentaenoic Acid (EPA) were increased by fish oil, flaxseed oil, or rapeseed oil. Effects of supplementation increasing DHA and EPA were detected in F, FL, and R. Compared with C, fish oil significantly increased low-density lipoprotein cholesterol (LDL-C) in serum, flaxseed oil significantly reduced TC and increased very low-density lipoprotein cholesterol (VLDL-C), rapeseed oil significantly reduced TC and LDL-C in serum and increased VLDL-C, tallow significantly increased LDL-C. It is concluded that unsaturated fatty acids rich diets (fish oil, flaxseed oil, and rapeseed oil) might increase yolk PUFAs, reduce yolk cholesterol, and change serum lipid parameters without evident effect on egg qualities. © 2016 Poultry Science Association Inc.

Evaluation of Shiga toxin 2e-specific chicken egg yolk immunoglobulin: production and neutralization activity.

PubMed

Arimitsu, Hideyuki; Sasaki, Keiko; Kohda, Tomoko; Shimizu, Toshiyasu; Tsuji, Takao

2014-11-01

Chicken egg yolk immunoglobulin (IgY) against Shiga toxin 2e (Stx2e), a major cause of swine edema disease, was prepared to evaluate its possible clinical applications. The titer of Stx2e-specific IgY in egg yolk derived from three chickens that had been immunized with an Stx2e toxoid increased 2 weeks after primary immunization and remained high until 90 days after this immunization. Anti-Stx2e IgY was found to neutralize the toxicity of Stx2e by reacting with its A and B subunits, indicating that IgY is a cost-effective agent to develop for prophylactic foods or diagnosis kits for edema disease. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.

Neurotoxicity of a Fragment of the Amyloid Precursor Associated with Alzheimer's Disease

NASA Astrophysics Data System (ADS)

Yankner, Bruce A.; Dawes, Linda R.; Fisher, Shannon; Villa-Komaroff, Lydia; Oster-Granite, Mary Lou; Neve, Rachael L.

1989-07-01

Amyloid deposition in senile plaques and the cerebral vasculature is a marker of Alzheimer's disease. Whether amyloid itself contributes to the neurodegenerative process or is simply a by-product of that process is unknown. Pheochromocytoma (PC12) and fibroblast (NIH 3T3) cell lines were transfected with portions of the gene for the human amyloid precursor protein. Stable PC12 cell transfectants expressing a specific amyloid-containing fragment of the precursor protein gradually degenerated when induced to differentiate into neuronal cells with nerve growth factor. Conditioned medium from these cells was toxic to neurons in primary hippocampal cultures, and the toxic agent could be removed by immunoabsorption with an antibody directed against the amyloid polypeptide. Thus, a peptide derived from the amyloid precursor may be neurotoxic.

Metabolic Characterization of Intact Cells Reveals Intracellular Amyloid Beta but Not Its Precursor Protein to Reduce Mitochondrial Respiration

PubMed Central

Schaefer, Patrick M.; von Einem, Bjoern; Walther, Paul; Calzia, Enrico; von Arnim, Christine A. F.

2016-01-01

One hallmark of Alzheimer´s disease are senile plaques consisting of amyloid beta (Aβ), which derives from the processing of the amyloid precursor protein (APP). Mitochondrial dysfunction has been linked to the pathogenesis of Alzheimer´s disease and both Aβ and APP have been reported to affect mitochondrial function in isolated systems. However, in intact cells, considering a physiological localization of APP and Aβ, it is pending what triggers the mitochondrial defect. Thus, the aim of this study was to dissect the impact of APP versus Aβ in inducing mitochondrial alterations with respect to their subcellular localization. We performed an overexpression of APP or beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), increasing APP and Aβ levels or Aβ alone, respectively. Conducting a comprehensive metabolic characterization we demonstrate that only APP overexpression reduced mitochondrial respiration, despite lower extracellular Aβ levels compared to BACE overexpression. Surprisingly, this could be rescued by a gamma secretase inhibitor, oppositionally indicating an Aβ-mediated mitochondrial toxicity. Analyzing Aβ localization revealed that intracellular levels of Aβ and an increased spatial association of APP/Aβ with mitochondria are associated with reduced mitochondrial respiration. Thus, our data provide marked evidence for a prominent role of intracellular Aβ accumulation in Alzheimer´s disease associated mitochondrial dysfunction. Thereby it highlights the importance of the localization of APP processing and intracellular transport as a decisive factor for mitochondrial function, linking two prominent hallmarks of neurodegenerative diseases. PMID:28005987

Differential regulation of amyloid precursor protein sorting with pathological mutations results in a distinct effect on amyloid-β production.

PubMed

Lin, Yen-Chen; Wang, Jia-Yi; Wang, Kai-Chen; Liao, Jhih-Ying; Cheng, Irene H

2014-11-01

The deposition of amyloid-β (Aβ) peptide, which is generated from amyloid precursor protein (APP), is the pathological hallmark of Alzheimer's disease (AD). Three APP familial AD mutations (D678H, D678N, and H677R) located at the sixth and seventh amino acid of Aβ have distinct effect on Aβ aggregation, but their influence on the physiological and pathological roles of APP remain unclear. We found that the D678H mutation strongly enhances amyloidogenic cleavage of APP, thus increasing the production of Aβ. This enhancement of amyloidogenic cleavage is likely because of the acceleration of APPD678H sorting into the endosomal-lysosomal pathway. In contrast, the APPD678N and APPH677R mutants do not cause the same effects. Therefore, this study indicates a regulatory role of D678H in APP sorting and processing, and provides genetic evidence for the importance of APP sorting in AD pathogenesis. The internalization of amyloid precursor protein (APP) increases its opportunity to be processed by β-secretase and to produce Amyloid-β (Aβ) that causes Alzheimer's disease (AD). We report a pathogenic APPD678H mutant that enhances APP internalization into the endosomal-lysosomal pathway and thus promotes the β-secretase cleavage and Aβ production. This study provides genetic evidence for the importance of APP sorting in AD pathogenesis. © 2014 International Society for Neurochemistry.

Supplementing glycosylation: A review of applying nucleotide-sugar precursors to growth medium to affect therapeutic recombinant protein glycoform distributions.

PubMed

Blondeel, Eric J M; Aucoin, Marc G

2018-06-15

Glycosylation is a critical quality attribute (CQA) of many therapeutic proteins, particularly monoclonal antibodies (mAbs), and is a major consideration in the approval of biosimilar biologics due to its effects to therapeutic efficacy. Glycosylation generates a distribution of glycoforms, resulting in glycoproteins with inherent molecule-to-molecule heterogeneity, capable of activating (or failing to activate) different effector functions of the immune system. Glycoforms can be affected by the supplementation of nucleotide-sugar precursors, and related components, to culture growth medium, affecting the metabolism of glycosylation. These supplementations has been demonstrated to increase nucleotide-sugar intracellular pools, and impact glycoform distributions, but with varied results. These variations can be attributed to five key factors: Differences between cell platforms (enzyme/transporter expression levels); differences between recombinant proteins produced (glycan-site accessibility); the fermentation and sampling timeline (glucose availability and exoglycosidase accumulation); glutamine levels (affecting ammonia levels, which impact Golgi pH, as well as UDP-GlcNAc pools); and finally, a lack of standardized metrics for observing shifts in glycoform distributions (glycosylation indices) across different experiments. The purpose of this review is to provide detail and clarity on the state of the art of supplementation strategies for nucleotide-sugar precursors for affecting glycosylation in cell culture processes, and to apply glycosylation indices for standardized comparisons across the field. Copyright © 2018. Published by Elsevier Inc.

Architecture engineering toward highly active palladium integrated titanium dioxide yolk-double-shell nanoreactor for catalytic applications

NASA Astrophysics Data System (ADS)

Liu, Baocang; Wang, Qin; Yu, Shengli; Jing, Peng; Liu, Lixia; Xu, Guangran; Zhang, Jun

2014-09-01

Rational design of the hierarchical architecture of a material with well controlled functionality is crucially important for improving its properties. In this paper, we present the general strategies for rationally designing and constructing three types of hierarchical Pd integrated TiO2 double-shell architectures, i.e. yolk-double-shell TiO2 architecture (Pd@TiO2/Pd@TiO2) with yolk-type Pd nanoparticles residing inside the central cavity of the hollow TiO2 structure; ultrafine Pd nanoparticles homogenously dispersed on both the external and internal surfaces of the inner TiO2 shell; and double-shell TiO2 architecture (@TiO2/Pd@TiO2) with Pd nanoparticles solely loaded on the external surface of the inner TiO2 shell, and double-shell TiO2 architecture (@TiO2@Pd@TiO2) with Pd nanoparticles dispersed in the interlayer space of double TiO2 shells, via newly developed Pd2+ ion-diffusion and Pd sol impregnation methodologies. These architectures are well controlled in structure, size, morphology, and configuration with Pd nanoparticles existing in various locations. Owing to the variable synergistic effects arising from the location discrepancies of Pd nanoparticle in the architectures, they exhibit remarkable variations in catalytic activity. In particular, different from previously reported yolk-shell structures, the obtained yolk-double-shell Pd@TiO2/Pd@TiO2 architecture, which is revealed for the first time, possesses a uniform hierarchical structure, narrow size distribution, and good monodispersibility, and it creates two Pd-TiO2 interfaces on the external and internal surfaces of the inner TiO2 shell, leading to the strongest synergistic effect of Pd nanoparticles with TiO2 shell. Furthermore, the interlayer chamber between the double TiO2 shells connecting with the central cavity of the hollow TiO2 structure through the mesoporous TiO2 wall forms a nanoreactor for enriching the reactants and preventing the deletion of Pd nanoparticles during the reaction, thus

Overexpression of amyloid precursor protein increases copper content in HEK293 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suazo, Miriam; Hodar, Christian; Morgan, Carlos

2009-05-15

Amyloid precursor protein (APP) is a transmembrane glycoprotein widely expressed in mammalian tissues and plays a central role in Alzheimer's disease. However, its physiological function remains elusive. Cu{sup 2+} binding and reduction activities have been described in the extracellular APP135-156 region, which might be relevant for cellular copper uptake and homeostasis. Here, we assessed Cu{sup 2+} reduction and {sup 64}Cu uptake in two human HEK293 cell lines overexpressing APP. Our results indicate that Cu{sup 2+} reduction increased and cells accumulated larger levels of copper, maintaining cell viability at supra-physiological levels of Cu{sup 2+} ions. Moreover, wild-type cells exposed to bothmore » Cu{sup 2+} ions and APP135-155 synthetic peptides increased copper reduction and uptake. Complementation of function studies in human APP751 transformed Fre1 defective Saccharomyces cerevisiae cells rescued low Cu{sup 2+} reductase activity and increased {sup 64}Cu uptake. We conclude that Cu{sup 2+} reduction activity of APP facilitates copper uptake and may represent an early step in cellular copper homeostasis.« less

Bioavailability of lutein in corn distillers dried grains with solubles relative to lutein in corn gluten meal based on lutein retention in egg yolk.

PubMed

Shin, Hye Seong; Kim, Jong Woong; Lee, Dong Gu; Lee, Sanghyun; Kil, Dong Yong

2016-08-01

Dietary lutein and its food sources have gained great attention due to its health-promoting effects on humans, especially for certain eye diseases. However, relative bioavailability (RBV) of lutein among lutein-rich feed ingredients that lead to lutein-enriched egg production has not been determined. Thus, the RBV of lutein in corn distillers dried grains with solubles (DDGS) as compared to lutein in corn gluten meal (CGM) was evaluated based on lutein retention in egg yolk. Increasing inclusion levels of DDGS or CGM in diets increased (linear, P < 0.01) Roche colour score and lutein concentrations of egg yolk without affecting laying performance. Multiple regression analysis revealed that the bioavailability of lutein in DDGS was less (P < 0.05) than that of lutein in CGM, with the RBV of lutein in DDGS being 61.6% when the bioavailability of lutein in CGM was assumed to be 100% for lutein retention in egg yolk. The results of the present experiment indicate that the DDGS can be a potential ingredient for laying hens to improve egg yolk colour and lutein concentrations of egg yolk although lutein in DDGS is less bioavailable than lutein in CGM. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

In vivo neuronal synthesis and axonal transport of Kunitz protease inhibitor (KPI)-containing forms of the amyloid precursor protein.

PubMed

Moya, K L; Confaloni, A M; Allinquant, B

1994-11-01

We have shown previously that the amyloid precursor protein (APP) is synthesized in retinal ganglion cells and is rapidly transported down the axons, and that different molecular weight forms of the precursor have different developmental time courses. Some APP isoforms contain a Kunitz protease inhibitor (KPI) domain, and APP that lacks the KPI domain is considered the predominant isoform in neurons. We now show that, among the various rapidly transported APPs, a 140-kDa isoform contains the KPI domain. This APP isoform is highly expressed in rapidly growing retinal axons, and it is also prominent in adult axon endings. This 140-kDa KPI-containing APP is highly sulfated compared with other axonally transported isoforms. These results show that APP with the KPI domain is a prominent isoform synthesized in neurons in vivo, and they suggest that the regulation of protease activity may be an important factor during the establishment of neuronal connections.

Inactivation of Protein Tyrosine Phosphatase Receptor Type Z by Pleiotrophin Promotes Remyelination through Activation of Differentiation of Oligodendrocyte Precursor Cells.

PubMed

Kuboyama, Kazuya; Fujikawa, Akihiro; Suzuki, Ryoko; Noda, Masaharu

2015-09-02

Multiple sclerosis (MS) is a progressive neurological disorder associated with myelin destruction and neurodegeneration. Oligodendrocyte precursor cells (OPCs) present in demyelinated lesions gradually fail to differentiate properly, so remyelination becomes incomplete. Protein tyrosine phosphatase receptor type Z (PTPRZ), one of the most abundant protein tyrosine phosphatases expressed in OPCs, is known to suppress oligodendrocyte differentiation and maintain their precursor cell stage. In the present study, we examined the in vivo mechanisms for remyelination using a cuprizone-induced demyelination model. Ptprz-deficient and wild-type mice both exhibited severe demyelination and axonal damage in the corpus callosum after cuprizone feeding. The similar accumulation of OPCs was observed in the lesioned area in both mice; however, remyelination was significantly accelerated in Ptprz-deficient mice after the removal of cuprizone. After demyelination, the expression of pleiotrophin (PTN), an inhibitory ligand for PTPRZ, was transiently increased in mouse brains, particularly in the neurons involved, suggesting its role in promoting remyelination by inactivating PTPRZ activity. In support of this view, oligodendrocyte differentiation was augmented in a primary culture of oligodendrocyte-lineage cells from wild-type mice in response to PTN. In contrast, these cells from Ptprz-deficient mice showed higher oligodendrocyte differentiation without PTN and differentiation was not enhanced by its addition. We further demonstrated that PTN treatment increased the tyrosine phosphorylation of p190 RhoGAP, a PTPRZ substrate, using an established line of OPCs. Therefore, PTPRZ inactivation in OPCs by PTN, which is secreted from demyelinated axons, may be the mechanism responsible for oligodendrocyte differentiation during reparative remyelination in the CNS. Multiple sclerosis (MS) is an inflammatory disease of the CNS that destroys myelin, the insulation that surrounds axons

Effect of egg weight on composition, embryonic growth, and expression of amino acid transporter genes in yolk sac membranes and small intestines of the domestic pigeon (Columba livia).

PubMed

Chen, M X; Li, X G; Yan, H C; Wang, X Q; Gao, C Q

2016-06-01

The objective of this study was to investigate the effect of egg weight on the composition of the egg, the growth of the embryo, and the expression of amino acid transporter genes in the yolk sac membranes and small intestines of the domestic pigeon (Columba livia). A total of 240 fertilized eggs were collected and divided into two groups based on the weight of the eggs, light (LE) and heavy (HE). The composition of 20 eggs from each group was measured, and the remaining eggs were weighed and placed in an incubator. On embryonic days (E) 9, 11, 13, and 15 and day of hatch (DOH), 15 embryos/hatchlings from each group were measured for embryonic growth, and samples were collected. The HE had heavier yolk and albumen weights than the LE (P < 0.01). Compared with the LE, the HE had heavier yolk-free embryonic body and yolk sac weights from E13 to DOH (P < 0.05). Additionally, the HE had larger yolk sac membrane weights from E13 to E15 (P < 0.05) and had more residual yolk sac content on DOH than those of the LE (P < 0.01). The yolk absorption was greater for the HE than for the LE from E11 to E13 (P < 0.05). Furthermore, the abundance of CAT2 and PepT1 mRNA in the yolk sac membranes was greater in the HE than in the LE on E13 (P < 0.05). Compared with the LE, the gene expression of EAAT2 in the intestine on E13 was greater in the HE, whereas the expression of EAAT3 was lower in the HE (P < 0.05). Taken together, our results suggest that egg weight influenced the composition of the eggs, embryonic development, and expression of amino acid transporter genes in the yolk sac membranes and small intestines of pigeon embryos. © 2016 Poultry Science Association Inc.

Room-temperature H2S Gas Sensor Based on Au-doped ZnFe2O4 Yolk-shell Microspheres.

PubMed

Yan, Yin; Nizamidin, Patima; Turdi, Gulmira; Kari, Nuerguli; Yimit, Abliz

2017-01-01

Room-temperature type H 2 S sensing devices that use Au-doped ZnFe 2 O 4 yolk-shell microspheres as the active material have been fabricated using a solvothermal method as well as subsequent annealing and a chemical etching process. The samples are characterized using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS). The results demonstrate that the doping of Au does not change the spinel structure of the products, which were yolk-shell microspheres, while the particle size varied with the Au doping concentration. Also, the as-fabricated sensor device exhibited excellent selectivity toward H 2 S gas at the room temperature; the gas-sensing property of 2 wt% Au-doped ZnFe 2 O 4 microspheres was the best. The Au-doped ZnFe 2 O 4 yolk-shell microspheres can be promising as a sensing material for H 2 S gas detecting at room temperature.

Cloning and expression profiling of the VLDLR gene associated with egg performance in duck (Anas platyrhynchos).

PubMed

Wang, Cui; Li, Shi-Jun; Yu, Wen-Hua; Xin, Qing-Wu; Li, Chuang; Feng, Yan-Ping; Peng, Xiu-Li; Gong, Yan-Zhang

2011-08-05

The very low density lipoprotein receptor gene (VLDLR), a member of the low density lipoprotein receptor (LDLR) gene family, plays a crucial role in the synthesis of yolk protein precursors in oviparous species. Differential splicing of this gene has been reported in human, rabbit and rat. In chicken, studies showed that the VLDLR protein on the oocyte surface mediates the uptake of yolk protein precursors into growing oocytes. However, information on the VLDLR gene in duck is still scarce. Full-length duck VLDLR cDNA was obtained by comparative cloning and rapid amplification of cDNA ends (RACE). Tissue expression patterns were analysed by semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR). Association between the different genotypes and egg performance traits was investigated with the general linear model (GLM) procedure of the SAS® software package. In duck, two VLDLR transcripts were identified, one transcript (variant-a) containing an O-linked sugar domain and the other (variant-b) not containing this sugar domain. These transcripts share ~70 to 90% identity with their counterparts in other species. A phylogenetic tree based on amino acid sequences showed that duck VLDLR proteins were closely related with those of chicken and zebra finch. The two duck VLDLR transcripts are differentially expressed i.e. VLDLR-a is mainly expressed in muscle tissue and VLDLR-b in reproductive organs. We have localized the duck VLDLR gene on chromosome Z. An association analysis using two completely linked SNP sites (T/C at position 2025 bp of the ORF and G/A in intron 13) and records from two generations demonstrated that the duck VLDLR gene was significantly associated with egg production (P < 0.01), age of first egg (P < 0.01) and body weight of first egg (P < 0.05). Duck and chicken VLDLR genes probably perform similar function in the development of growing oocytes and deposition of yolk lipoprotein. Therefore, VLDLR could be a candidate gene for duck

Cloning and expression profiling of the VLDLR gene associated with egg performance in duck (Anas platyrhynchos)

PubMed Central

2011-01-01

Background The very low density lipoprotein receptor gene (VLDLR), a member of the low density lipoprotein receptor (LDLR) gene family, plays a crucial role in the synthesis of yolk protein precursors in oviparous species. Differential splicing of this gene has been reported in human, rabbit and rat. In chicken, studies showed that the VLDLR protein on the oocyte surface mediates the uptake of yolk protein precursors into growing oocytes. However, information on the VLDLR gene in duck is still scarce. Methods Full-length duck VLDLR cDNA was obtained by comparative cloning and rapid amplification of cDNA ends (RACE). Tissue expression patterns were analysed by semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR). Association between the different genotypes and egg performance traits was investigated with the general linear model (GLM) procedure of the SAS® software package. Results In duck, two VLDLR transcripts were identified, one transcript (variant-a) containing an O-linked sugar domain and the other (variant-b) not containing this sugar domain. These transcripts share ~70 to 90% identity with their counterparts in other species. A phylogenetic tree based on amino acid sequences showed that duck VLDLR proteins were closely related with those of chicken and zebra finch. The two duck VLDLR transcripts are differentially expressed i.e. VLDLR-a is mainly expressed in muscle tissue and VLDLR-b in reproductive organs. We have localized the duck VLDLR gene on chromosome Z. An association analysis using two completely linked SNP sites (T/C at position 2025 bp of the ORF and G/A in intron 13) and records from two generations demonstrated that the duck VLDLR gene was significantly associated with egg production (P < 0.01), age of first egg (P < 0.01) and body weight of first egg (P < 0.05). Conclusions Duck and chicken VLDLR genes probably perform similar function in the development of growing oocytes and deposition of yolk lipoprotein. Therefore

Activation of PPARδ prevents endothelial dysfunction induced by overexpression of amyloid-β precursor protein.

PubMed

d'Uscio, Livius V; Das, Pritam; Santhanam, Anantha V R; He, Tongrong; Younkin, Steven G; Katusic, Zvonimir S

2012-12-01

Existing evidence suggests that amyloid-β precursor protein (APP) causes endothelial dysfunction and contributes to pathogenesis of atherosclerosis. In the present study, experiments were designed to: (1) determine the mechanisms underlying endothelial dysfunction and (2) define the effects of peroxisome proliferator-activated receptor delta (PPARδ) ligand on endothelial function in transgenic Tg2576 mice overexpressing mutated human APP. Confocal microscopy and western blot analyses of wild-type mice aortas provided evidence that APP protein is mainly present in endothelial cells. Overexpression of APP significantly impaired endothelium-dependent relaxations to acetylcholine and phosphorylation of endothelial nitric oxide synthase at Ser(1177) in aortas. HPLC analysis revealed that tetrahydrobiopterin (BH(4)) levels were reduced in Tg2576 mice aortas. This was caused by increased oxidation of BH(4) and reduced expression and activity of GTP-cyclohydrolase I. Furthermore, gp91phox protein expression and superoxide anion production were increased in aortas of Tg2576 mice. This augmented superoxide formation was completely prevented by the NADPH oxidase inhibitor VAS2870. Expression of copper-/zinc-superoxide dismutase (Cu/ZnSOD) and extracellular SOD was downregulated. Treatment with PPARδ ligand GW501516 (2 mg/kg/day) for 14 days significantly increased BH(4) bioavailability and improved endothelium-dependent relaxations in Tg2576 mice aortas. GW501516 also normalized protein expression of gp91(phox) and SODs, thereby reducing production of superoxide anion in the aortas. Our results suggest that in APP transgenic mice loss of nitric oxide and increased oxidative stress are the major causes of endothelial dysfunction. The vascular protective effects of GW501516 in Tg2576 mice appear to be critically dependent on prevention of superoxide anion production.

In vitro assessment of soybean lecithin and egg yolk based diluents for cryopreservation of goat semen.

PubMed

Salmani, Hossein; Towhidi, Armin; Zhandi, Mahdi; Bahreini, Majid; Sharafi, Mohsen

2014-04-01

Soybean lecithin is a suitable plant-based cryoprotectant for freezing ruminant sperm. Optimum level of lecithin was not clear for goat semen cryopreservation. The objective of this study was to investigate the effects of different levels of soybean lecithin in semen extender on post-thaw sperm quality including CASA-motion parameters, viability, plasma membrane integrity and lipid peroxidation. Semen samples were collected from 4 Mahabadi bucks using an artificial vagina. Different concentrations of soy lecithin (SL, 0.5%, 1%, 1.5%, 2% and 2.5% w/v) were compared to 15% (v/v) egg yolk-based extender (TR-EY). No significant difference was observed for sperm progressive motility, viability or plasma membrane integrity in 1.5% SL media (33.8%, 66%, and 62.7%, respectively) and TR-EY medium (35.4%, 67.2%, and 64.9%, respectively). Sperm motion characteristics (VAP, VSL, VCL, ALH and LIN) and rapid spermatozoa were improved with extender containing 1% and 1.5% SL, compared to TR-EY extender. Furthermore, egg yolk produced significantly higher malondialdehyde (4.02±0.21) than other groups. Results suggest that the optimal lecithin concentration in the semen extender was 1.5% and also soy lecithin can substitute for egg yolk during cryopreservation for caprine sperm. Copyright © 2014 Elsevier Inc. All rights reserved.

Trans fatty acids enhance amyloidogenic processing of the Alzheimer amyloid precursor protein (APP).

PubMed

Grimm, Marcus O W; Rothhaar, Tatjana L; Grösgen, Sven; Burg, Verena K; Hundsdörfer, Benjamin; Haupenthal, Viola J; Friess, Petra; Kins, Stefan; Grimm, Heike S; Hartmann, Tobias

2012-10-01

Hydrogenation of oils and diary products of ruminant animals leads to an increasing amount of trans fatty acids in the human diet. Trans fatty acids are incorporated in several lipids and accumulate in the membrane of cells. Here we systematically investigate whether the regulated intramembrane proteolysis of the amyloid precursor protein (APP) is affected by trans fatty acids compared to the cis conformation. Our experiments clearly show that trans fatty acids compared to cis fatty acids increase amyloidogenic and decrease nonamyloidogenic processing of APP, resulting in an increased production of amyloid beta (Aβ) peptides, main components of senile plaques, which are a characteristic neuropathological hallmark for Alzheimer's disease (AD). Moreover, our results show that oligomerization and aggregation of Aβ are increased by trans fatty acids. The mechanisms identified by this in vitro study suggest that the intake of trans fatty acids potentially increases the AD risk or causes an earlier onset of the disease. Copyright © 2012 Elsevier Inc. All rights reserved.

Intermolecular cleavage of hepatitis A virus (HAV) precursor protein P1-P2 by recombinant HAV proteinase 3C.

PubMed Central

Kusov, Y Y; Sommergruber, W; Schreiber, M; Gauss-Müller, V

1992-01-01

Active proteinase 3C of hepatitis A virus (HAV) was expressed in bacteria either as a mature enzyme or as a protein fused to the entire polymerase 3D or to a part of it, and their identities were shown by immunoblot analysis. Intermolecular cleavage activity was demonstrated by incubating in vitro-translated and radiolabeled HAV precursor protein P1-P2 with extracts of bacteria transformed with plasmids containing recombinant HAV 3C. Identification of cleavage products P1, VP1, and VPO-VP3 by immunoprecipitation clearly demonstrates that HAV 3C can cleave between P1 and P2 as well as within P1 and thus shows an activity profile similar to that of cardiovirus 3C. Images PMID:1328690

A complex between contactin-1 and the protein tyrosine phosphatase PTPRZ controls the development of oligodendrocyte precursor cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lamprianou, Smaragda; Chatzopoulou, Elli; Thomas, Jean-Léon

The six members of the contactin (CNTN) family of neural cell adhesion molecules are involved in the formation and maintenance of the central nervous system (CNS) and have been linked to mental retardation and neuropsychiatric disorders such as autism. Five of the six CNTNs bind to the homologous receptor protein tyrosine phosphatases gamma (PTPRG) and zeta (PTPRZ), but the biological roles of these interactions remain unclear. We report here the cocrystal structure of the carbonic anhydrase-like domain of PTPRZ bound to tandem Ig repeats of CNTN1 and combine these structural data with binding assays to show that PTPRZ binds specificallymore » to CNTN1 expressed at the surface of oligodendrocyte precursor cells. Furthermore, analyses of glial cell populations in wild-type and PTPRZ-deficient mice show that the binding of PTPRZ to CNTN1 expressed at the surface of oligodendrocyte precursor cells inhibits their proliferation and promotes their development into mature oligodendrocytes. Overall, these results implicate the PTPRZ/CNTN1 complex as a previously unknown modulator of oligodendrogenesis.« less

The Amyloid Precursor Protein (APP) Triplicated Gene Impairs Neuronal Precursor Differentiation and Neurite Development through Two Different Domains in the Ts65Dn Mouse Model for Down Syndrome*

PubMed Central

Trazzi, Stefania; Fuchs, Claudia; Valli, Emanuele; Perini, Giovanni; Bartesaghi, Renata; Ciani, Elisabetta

2013-01-01

Intellectual disability in Down syndrome (DS) appears to be related to severe proliferation impairment during brain development. Recent evidence shows that it is not only cellular proliferation that is heavily compromised in DS, but also cell fate specification and dendritic maturation. The amyloid precursor protein (APP), a gene that is triplicated in DS, plays a key role in normal brain development by influencing neural precursor cell proliferation, cell fate specification, and neuronal maturation. APP influences these processes via two separate domains, the APP intracellular domain (AICD) and the soluble secreted APP. We recently found that the proliferation impairment of neuronal precursors (NPCs) from the Ts65Dn mouse model for DS was caused by derangement of the Shh pathway due to overexpression of patched1(Ptch1), its inhibitory regulator. Ptch1 overexpression was related to increased levels within the APP/AICD system. The overall goal of this study was to determine whether APP contributes to neurogenesis impairment in DS by influencing in addition to proliferation, cell fate specification, and neurite development. We found that normalization of APP expression restored the reduced neuronogenesis, the increased astrogliogenesis, and the reduced neurite length of trisomic NPCs, indicating that APP overexpression underpins all aspects of neurogenesis impairment. Moreover, we found that two different domains of APP impair neuronal differentiation and maturation in trisomic NPCs. The APP/AICD system regulates neuronogenesis and neurite length through the Shh pathway, whereas the APP/secreted AP system promotes astrogliogenesis through an IL-6-associated signaling cascade. These results provide novel insight into the mechanisms underlying brain development alterations in DS. PMID:23740250

Measurement of Iron in Egg Yolk: An Instrumental Analysis Experiment Using Biochemical Principles

ERIC Educational Resources Information Center

Maloney, Kevin M.; Quiazon, Emmanuel M.; Indralingam, Ramee

2008-01-01

The generally accepted method to determine iron content in food is by acid digestion or dry ashing and subsequent flame atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry. We have developed an experiment that chemically extracts the iron from an egg yolk and quantifies it using UV-vis absorption…

Processing of the precursor of protamine P2 in mouse. Peptide mapping and N-terminal sequence analysis of intermediates.

PubMed Central

Carré-Eusèbe, D; Lederer, F; Lê, K H; Elsevier, S M

1991-01-01

Protamine P2, the major basic chromosomal protein of mouse spermatozoa, is synthesized as a precursor almost twice as long as the mature protein, its extra length arising from an N-terminal extension of 44 amino acid residues. This precursor is integrated into chromatin of spermatids, and the extension is processed during chromatin condensation in the haploid cells. We have studied processing in the mouse and have identified two intermediates generated by proteolytic cleavage of the precursor. H.p.l.c. separated protamine P2 from four other spermatid proteins, including the precursor and three proteins known to possess physiological characteristics expected of processing intermediates. Peptide mapping indicated that all of these proteins were structurally similar. Two major proteins were further purified by PAGE, transferred to poly(vinylidene difluoride) membranes and submitted to automated N-terminal sequence analysis. Both sequences were found within the deduced sequence of the precursor extension. The N-terminus of the larger intermediate, PP2C, was Gly-12, whereas the N-terminus of the smaller, PP2D, was His-21. Both processing sites involved a peptide bond in which the carbonyl function was contributed by an acidic amino acid. Images Fig. 1. Fig. 3. Fig. 4. PMID:1854346

Rational design of Fe3O4@C yolk-shell nanorods constituting a stable anode for high-performance Li/Na-ion batteries.

PubMed

Wang, Beibei; Zhang, Xing; Liu, Xiaojie; Wang, Gang; Wang, Hui; Bai, Jintao

2018-05-24

In the current research project, we have prepared a novel Fe 3 O 4 @mesoporous carbon nanorod (denoted as Fe 3 O 4 @C) anode with yolk-shell structure for Li/Na-ion batteries via one-pot and surfactant-free synthesis strategy. The yolk-shell structure consists of Fe 3 O 4 nanorod yolk completely protected by a well-conductive mesoporous carbon shell. The substantial void space in the Fe 3 O 4 @C yolk-shell nanorod can not only accommodate the full volume expansion of inner Fe 3 O 4 nanorod, but also preserve the structural integrity of the Fe 3 O 4 @C anode and develop a stable SEI film on the outside mesoporous carbon shell during the repeated Li + /Na + insertion/extraction processes. As for lithium storage, the Fe 3 O 4 @C electrode exhibits a high specific capacity (1247 mAh g -1 ), stable cycling performance (a specific capacity of 954 mAh g -1 after 200 cycles at a current density of 0.5 A g -1 ) and excellent rate capability (specific capabilities of 1122, 958, 783, 577, and 374 mAh g -1 at 0.5, 1, 2, 4, and 8 A g -1 , respectively). As for sodium storage, the Fe 3 O 4 @C yolk-shell nanorods also maintain a reversible capacity of approximate 424 mAh g -1 at 0.1 A g -1 after 100 cycles. Copyright © 2018. Published by Elsevier Inc.

DNA methyltransferase-3 like protein expression in various histological types of testicular germ cell tumor.

PubMed

Matsuoka, Taeko; Kawai, Koji; Ando, Satoshi; Sugita, Shintaro; Kandori, Shuya; Kojima, Takahiro; Miyazaki, Jun; Nishiyama, Hiroyuki

2016-05-01

DNA methyltransferase 3-like plays an important role in germ cell development. The aim of this study was to analyse the DNA methyltransferase 3-like protein expression in testicular germ cell tumors. The immunohistochemical expression of DNA methyltransferase 3-like was examined in 86 testicular germ cell tumor specimens in various clinical settings. The association between DNA methyltransferase 3-like expression and disease stage was analyzed. DNA methyltransferase 3-like was strongly expressed in seven of the eight pure embryonal carcinomas (87.5%). Partial DNA methyltransferase 3-like expression was observed in 6 of 23 (26.1%) pure seminomas. Various degrees of DNA methyltransferase 3-like expression was observed in all four pure yolk sac tumors, of which three were prepubertal yolk sac tumors. In mixed germ cell tumors, DNA methyltransferase 3-like protein was expressed in various degrees in elements of the embryonal carcinoma (14/18, 77.8%), seminoma (4/11, 36.4%), teratoma (4/7, 57.1%) and choriocarcinoma (3/3, 100%) but not in the yolk sac tumors (0/4). When DNA methyltransferase 3-like expression was analyzed according to disease stages, it was significantly correlated with advanced seminoma rather than Stage I seminoma (46.2 vs. 0%, P = 0.019), whereas there was no significant difference in the DNA methyltransferase 3-like-positive proportion between Stage I and advanced disease in the mixed germ cell tumors. Our findings suggest that DNA methyltransferase 3-like protein may play roles not only in the development of embryonal carcinoma but also in the development of advanced pure seminoma and pure yolk sac tumor. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Amyloid precursor protein-induced axonopathies are independent of amyloid-beta peptides.

PubMed

Stokin, Gorazd B; Almenar-Queralt, Angels; Gunawardena, Shermali; Rodrigues, Elizabeth M; Falzone, Tomás; Kim, Jungsu; Lillo, Concepción; Mount, Stephanie L; Roberts, Elizabeth A; McGowan, Eileen; Williams, David S; Goldstein, Lawrence S B

2008-11-15

Overexpression of amyloid precursor protein (APP), as well as mutations in the APP and presenilin genes, causes rare forms of Alzheimer's disease (AD). These genetic changes have been proposed to cause AD by elevating levels of amyloid-beta peptides (Abeta), which are thought to be neurotoxic. Since overexpression of APP also causes defects in axonal transport, we tested whether defects in axonal transport were the result of Abeta poisoning of the axonal transport machinery. Because directly varying APP levels also alters APP domains in addition to Abeta, we perturbed Abeta generation selectively by combining APP transgenes in Drosophila and mice with presenilin-1 (PS1) transgenes harboring mutations that cause familial AD (FAD). We found that combining FAD mutant PS1 with FAD mutant APP increased Abeta42/Abeta40 ratios and enhanced amyloid deposition as previously reported. Surprisingly, however, this combination suppressed rather than increased APP-induced axonal transport defects in both Drosophila and mice. In addition, neuronal apoptosis induced by expression of FAD mutant human APP in Drosophila was suppressed by co-expressing FAD mutant PS1. We also observed that directly elevating Abeta with fusions to the Familial British and Danish Dementia-related BRI protein did not enhance axonal transport phenotypes in APP transgenic mice. Finally, we observed that perturbing Abeta ratios in the mouse by combining FAD mutant PS1 with FAD mutant APP did not enhance APP-induced behavioral defects. A potential mechanism to explain these findings was suggested by direct analysis of axonal transport in the mouse, which revealed that axonal transport or entry of APP into axons is reduced by FAD mutant PS1. Thus, we suggest that APP-induced axonal defects are not caused by Abeta.

Egg yolk IgY: protection against rotavirus induced diarrhea and modulatory effect on the systemic and mucosal antibody responses in newborn calves.

PubMed

Vega, C; Bok, M; Chacana, P; Saif, L; Fernandez, F; Parreño, V

2011-08-15

Bovine rotavirus (BRV) is an important cause of diarrhea in newborn calves. Local passive immunity is the most efficient protective strategy to control the disease. IgY technology (the use of chicken egg yolk immunoglobulins) is an economic and practical alternative to prevent BRV diarrhea in dairy calves. The aim of this study was to evaluate the protection and immunomodulation induced by the oral administration of egg yolk enriched in BRV specific IgY to experimentally BRV infected calves. All calves in groups Gp 1, 2 and 3 received control colostrum (CC; BRV virus neutralization Ab titer - VN=65,536; ELISA BRV IgG(1)=16,384) prior to gut closure. After gut closure, calves received milk supplemented with 6% BRV-immune egg yolk [(Gp 1) VN=2048; ELISA IgY Ab titer=4096] or non-immune control egg yolk [(Gp 2) VN<4; ELISA IgY Ab titer<4] twice a day, for 14 days. Calves receiving CC only or colostrum deprived calves (CD) fed antibody (Ab) free milk served as controls (Gp 3 and 4, respectively). Calves were inoculated with 10(5.85)focus forming units (FFU) of virulent BRV IND at 2 days of age. Control calves (Gp 3 and 4) and calves fed control IgY (Gp 2) were infected and developed severe diarrhea. Around 80% calves in Gp 1 (IgY 4096) were infected, but they showed 80% (4/5) protection against BRV diarrhea. Bovine RV-specific IgY Ab were detected in the feces of calves in Gp 1, indicating that avian antibodies (Abs) remained intact after passage through the gastrointestinal tract. At post infection day 21, the duodenum was the major site of BRV specific antibody secreting cells (ASC) in all experimental groups. Mucosal ASC responses of all isotypes were significantly higher in the IgY treated groups, independently of the specificity of the treatment, indicating that egg yolk components modulated the immune response against BRV infection at the mucosal level. These results indicate that supplementing newborn calves' diets for the first 14 days of life with egg yolk

Egg Yolk IgY: Protection against Rotavirus induced Diarrhea and Modulatory effect on the systemic and mucosal antibody responses in newborn calves

PubMed Central

Vega, C.; Bok, M.; Chacana, P.; Saif, L.; Fernandez, F.; Parreño, V.

2011-01-01

Bovine rotavirus (BRV) is an important cause of diarrhea in newborn calves. Local passive immunity is the most efficient protective strategy to control the disease. IgY technology (the use of chicken egg yolk immunoglobulins) is an economic and practical alternative to prevent BRV diarrhea in dairy calves. The aim of this study was to evaluate the protection and immunomodulation induced by the oral administration of egg yolk enriched in BRV specific IgY to experimentally BRV infected calves. All calves in groups Gp 1, 2 and 3 received control colostrum (CC; BRV virus neutralization Ab titer – VN- =65,536; ELISA BRV IgG1 =16,384) prior to gut closure. After gut closure, calves received milk supplemented with 6% BRV-immune egg yolk [(Gp1) VN=2048; ELISA IgY Ab titer =4096] or non-immune control egg yolk [(Gp2) VN <4; ELISA IgY Ab titer <4) twice a day, for 14 days. Calves receiving CC only or colostrum deprived calves (CD) fed antibody (Ab) free milk served as controls (Gp 3 and 4, respectively). Calves were inoculated with 105.85 focus forming units (FFU) of virulent BRV IND at 2 days of age. Control calves (Gp 3 and 4) and calves fed control IgY (Gp 2) were infected and developed severe diarrhea. Around 80% calves in Gp 1 (IgY 4096) were infected, but they showed 80% (4/5) protection against BRV diarrhea. Bovine RV-specific IgY Ab were detected in the feces of calves in Gp 1, indicating that avian antibodies (Abs) remained intact after passage through the gastrointestinal tract. At post infection day 21, the duodenum was the major site of BRV specific antibody secreting cells (ASC) in all experimental groups. Mucosal ASC responses of all isotypes were significantly higher in the IgY treated groups, independently of the specificity of the treatment, indicating that egg yolk components modulated the immune response against BRV infection at the mucosal level. These results indicate that supplementing newborn calves’ diets for the first 14 days of life with egg

Modulation of beta-amyloid precursor protein trafficking and processing by the low density lipoprotein receptor family.

PubMed

Cam, Judy A; Bu, Guojun

2006-08-18

Amyloid-beta peptide (Abeta) accumulation in the brain is an early, toxic event in the pathogenesis of Alzheimer's disease (AD). Abeta is produced by proteolytic processing of a transmembrane protein, beta-amyloid precursor protein (APP), by beta- and gamma-secretases. Mounting evidence has demonstrated that alterations in APP cellular trafficking and localization directly impact its processing to Abeta. Recent studies have shown that members of the low-density lipoprotein receptor family, including LRP, LRP1B, SorLA/LR11, and apolipoprotein E (apoE) receptor 2, interact with APP and regulate its endocytic trafficking. Another common feature of these receptors is their ability to bind apoE, which exists in three isoforms in humans and the presence of the epsilon4 allele represents a genetic risk factor for AD. In this review, we summarize the current understanding of the function of these apoE receptors with a focus on their role in APP trafficking and processing. Knowledge of the interactions between these distinct low-density lipoprotein receptor family members and APP may ultimately influence future therapies for AD.

Activation of PPARδ prevents endothelial dysfunction induced by overexpression of amyloid-β precursor protein

PubMed Central

d'Uscio, Livius V.; Das, Pritam; Santhanam, Anantha V.R.; He, Tongrong; Younkin, Steven G.; Katusic, Zvonimir S.

2012-01-01

Aims Existing evidence suggests that amyloid-β precursor protein (APP) causes endothelial dysfunction and contributes to pathogenesis of atherosclerosis. In the present study, experiments were designed to: (1) determine the mechanisms underlying endothelial dysfunction and (2) define the effects of peroxisome proliferator-activated receptor delta (PPARδ) ligand on endothelial function in transgenic Tg2576 mice overexpressing mutated human APP. Methods and results Confocal microscopy and western blot analyses of wild-type mice aortas provided evidence that APP protein is mainly present in endothelial cells. Overexpression of APP significantly impaired endothelium-dependent relaxations to acetylcholine and phosphorylation of endothelial nitric oxide synthase at Ser1177 in aortas. HPLC analysis revealed that tetrahydrobiopterin (BH4) levels were reduced in Tg2576 mice aortas. This was caused by increased oxidation of BH4 and reduced expression and activity of GTP-cyclohydrolase I. Furthermore, gp91phox protein expression and superoxide anion production were increased in aortas of Tg2576 mice. This augmented superoxide formation was completely prevented by the NADPH oxidase inhibitor VAS2870. Expression of copper-/zinc-superoxide dismutase (Cu/ZnSOD) and extracellular SOD was downregulated. Treatment with PPARδ ligand GW501516 (2 mg/kg/day) for 14 days significantly increased BH4 bioavailability and improved endothelium-dependent relaxations in Tg2576 mice aortas. GW501516 also normalized protein expression of gp91phox and SODs, thereby reducing production of superoxide anion in the aortas. Conclusion Our results suggest that in APP transgenic mice loss of nitric oxide and increased oxidative stress are the major causes of endothelial dysfunction. The vascular protective effects of GW501516 in Tg2576 mice appear to be critically dependent on prevention of superoxide anion production. PMID:22886847

AaCAT1 of the Yellow Fever Mosquito, Aedes aegypti

PubMed Central

Hansen, Immo A.; Boudko, Dmitri Y.; Shiao, Shin-Hong; Voronov, Dmitri A.; Meleshkevitch, Ella A.; Drake, Lisa L.; Aguirre, Sarah E.; Fox, Jeffrey M.; Attardo, Geoffrey M.; Raikhel, Alexander S.

2011-01-01

Insect yolk protein precursor gene expression is regulated by nutritional and endocrine signals. A surge of amino acids in the hemolymph of blood-fed female mosquitoes activates a nutrient signaling system in the fat bodies, which subsequently derepresses yolk protein precursor genes and makes them responsive to activation by steroid hormones. Orphan transporters of the SLC7 family were identified as essential upstream components of the nutrient signaling system in the fat body of fruit flies and the yellow fever mosquito, Aedes aegypti. However, the transport function of these proteins was unknown. We report expression and functional characterization of AaCAT1, cloned from the fat body of A. aegypti. Expression of AaCAT1 transcript and protein undergoes dynamic changes during postembryonic development of the mosquito. Transcript expression was especially high in the third and fourth larval stages; however, the AaCAT1 protein was detected only in pupa and adult stages. Functional expression and analysis of AaCAT1 in Xenopus oocytes revealed that it acts as a sodium-independent cationic amino acid transporter, with unique selectivity to l-histidine at neutral pH (K0.5l-His = 0.34 ± 0.07 mm, pH 7.2). Acidification to pH 6.2 dramatically increases AaCAT1-specific His+-induced current. RNAi-mediated silencing of AaCAT1 reduces egg yield of subsequent ovipositions. Our data show that AaCAT1 has notable differences in its transport mechanism when compared with related mammalian cationic amino acid transporters. It may execute histidine-specific transport and signaling in mosquito tissues. PMID:21262963

Experiences and Perspectives of Polycystic Kidney Disease Patients following a Diet of Reduced Osmoles, Protein, and Acid Precursors Supplemented with Water: A Qualitative Study.

PubMed

Taylor, Jacob M; Ptomey, Lauren; Hamilton-Reeves, Jill M; Sullivan, Debra K; Creed, Catherine; Carlson, Susan E; Wesson, Donald E; Grantham, Jared J; Gibson, Cheryl A

2016-01-01

Salt, protein, acid precursors, and fluid intake have been identified as factors that influence cyst growth in ADPKD. Unfortunately, the feasibility of following these dietary restrictions/enhancements from a patient's point-of-view has yet to be studied. The purpose of this study is to understand better the experiences of patients following a relatively complex dietary prescription targeting these factors. Twelve adults with ADPKD and kidney function >30ml/min/1.73m2 were recruited from the University of Kansas Medical Center Polycystic Kidney Disease clinic. In a qualitative design, semi-structured interviews of participants were conducted following a four week dietary intervention (experimental diet lower in sodium, protein, and acid precursors, and supplemented with water) either face-to-face or by telephone. All interviews were recorded, transcribed verbatim, and checked for accuracy. Transcripts were analyzed thematically for emerging themes. Participants reported that eating less meat and more fruits and vegetables were the easiest components of the diet, whereas reaching the daily goal amount of fruits and vegetables and tracking the diet constantly were the most difficult components. Participants had little difficulty with fluid intake and reported the prescribed fluid goal as achievable. The tracking system for fruits and vegetables and protein was reported to be both helpful and intuitive, but tracking their intake on paper was tedious. Eating out was the most significant barrier to following the diet with some individuals avoiding restaurants in order to comply with the dietary prescription. Participants on the experimental diet heightened their awareness of the consumption of dietary salt, protein, acid precursors, and fluid intake. Additionally, most participants believed adherence to the prescribed diet was feasible. However, participants wanted less cumbersome ways to track and monitor the diet, especially given that the prescribed diet is designed

Amyloid precursor protein and Presenilin 1 interaction studied by FRET in human H4 cells.

PubMed

Nizzari, Mario; Venezia, Valentina; Bianchini, Paolo; Caorsi, Valentina; Diaspro, Alberto; Repetto, Emanuela; Thellung, Stefano; Corsaro, Alessandro; Carlo, Pia; Schettini, Gennaro; Florio, Tullio; Russo, Claudio

2007-01-01

The mayor pathologic hallmarks of Alzheimer's disease (AD) are senile plaque and neurofibrillary tangles. Senile plaque are primarily made up of deposits of amyloid-beta protein, a proteolytic product derived from the amyloid precursor protein (APP). APP is a transmembrane protein detected into the endoplasmic reticulum, in the Golgi apparatus, at the cell surface, recycled by endocytosis to endosomes, whose physiological function is unclear. Presenilins (PS), are a component of gamma-secretase complex that cleave alpha-CTFs (carboxy-terminal fragment), or beta-CTFs, leaving 40 or 42 amino acids amyloid-beta peptides and 58 or 56 amino acids intracellular domains (AICD). Where the amyloid-beta peptides is generated is not clear. The study of APP-PS interaction in specific cell compartments provides a good opportunity to light upon the molecular mechanisms regulating the activity of the "gamma-secretase complex," and where beta-amyloid is generated. In our study we used a biophysical assay of protein proximity: fluorescence resonance energy transfer (FRET), that can provide information about molecular interactions when two proteins are in the close proximity (<10 nm), to examine the subcellular localization and interaction between APP and PS1 in human neuroglioma cells (H4). Confocal microscopic analysis reveals extensive colocalization in different cells' compartment, and centrosomal or microtubule organizing center (MTOC) localization of APP and PS1, but not necessarily a close molecular interaction. We used FRET to determine if APP and PS1 interact at the cell centrosome. FRET data suggest a close interaction between APP and PS1 in subcellular compartments and at the centrosome of H4 cells. Using this approach we show that APP and PS1 are closely associated in the centrosomes of the H4 cell.

Termination of pregnancy at very early gestation without visible yolk sac on ultrasound.

PubMed

Heller, Rebecca; Cameron, Sharon

2015-04-01

Requests for termination of pregnancy (TOP) at very early gestation (≤6 weeks) can prove challenging for abortion services as the ultrasound feature usually accepted as definitive evidence of an intrauterine pregnancy (IUP), the presence of a yolk sac within a gestational sac, may not yet be evident. In 2011 the Edinburgh TOP service introduced a protocol permitting women to proceed to treatment without further investigations provided that ultrasound showed the features of an eccentrically placed gestational sac (≥3 mm) with a decidual reaction, and there were no signs, symptoms or risk factors for ectopic pregnancy. A retrospective audit was conducted of outcomes of women presenting for TOP at ≤6 weeks' gestation over a 2-year period using the hospital computerised database. A total of 1155 women presented for TOP with an ultrasound gestational age of ≤6 weeks. Of these, 1030 (89%) had ultrasound evidence of a yolk sac. Eighty-seven women (7.5%) had an eccentrically placed gestational sac with a decidual reaction. All 87 women fulfilled our criteria to proceed to medical TOP, and 66 did so. In the remaining 21 cases, further investigations were performed before they proceeded to medical TOP. Two (0.17%) medical TOPs failed, both in women whose initial ultrasound had shown a yolk sac. Women with ultrasound features consistent with a very early IUP (≥3 mm eccentrically placed gestational sac with a decidual reaction) and without signs, symptoms or risk factors for ectopic pregnancy can proceed directly to medical TOP without the need for delay for further ultrasonography. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Exploring cytoplasmic dynamics in zebrafish yolk cells by single particle tracking of fluorescent nanodiamonds

NASA Astrophysics Data System (ADS)

Chang, Cheng-Chun; Zhang, Bailin; Li, Che-Yu; Hsieh, Chih-Chien; Duclos, Guillaume; Treussart, François; Chang, Huan-Cheng

2012-02-01

Fluorescent nanodiamonds (FNDs) have recently developed into an exciting new tool for bioimaging applications. The material possesses several unique features including high biocompatibility, easy bioconjugation, and perfect photostability, making it a promising optical nanoprobe in vitro as well as in vivo. This work explores the potential application of this novel nanomaterial as a photostable, nontoxic tracer in vivo using zebrafish as a model organism. We introduced FNDs into the yolk of a zebrafish embryo by microinjection at the 1-cell stage. Movements of the injected particles were investigated by using single particle tracking techniques. We observed unidirectional and stop-and-go traffic as part of the intricate cytoplasmic movements in the yolk cell. We determined a velocity in the range of 0.19 - 0.40 μm/s for 40 particles moving along with the axial streaming in the early developmental stage (1 to 2 hours post fertilization) of the zebrafish embryos.

Productivity and some properties of immunoglobulin specific against Streptococcus mutans serotype c in chicken egg yolk (IgY).

PubMed

Chang, H M; Ou-Yang, R F; Chen, Y T; Chen, C C

1999-01-01

Hens were immunized on thighs by using whole cells of Streptococcus mutans MT8148 serotype c strain as antigen through intramuscular (im) and subcutaneous (sc) routes to investigate the difference of immunization reactions and the changes in yolk antibody activities against antigen after initial immunization. Several properties of crude IgY were examined to evaluate the stability during food processing. Results showed that the specificity of IgY of im treated hens was nearly 10 times as high as those of sc treated antibody. IgY from the hens immunized with the serotype c strain showed significant cross-reactions against serotypes e and f, while minor reactions against serotypes a, b, d, and g were observed. In thermal stability tests, IgY activity in both yolk and crude IgY decreased with the increasing temperature, from 70 to 80 degrees C, but the thermal denaturation rates between those two samples were not significantly different. The addition of high levels sucrose, maltose, glycerol, or 2% glycine displayed effective protection against thermal denaturation of IgY. Lyophilized yolk-5% gum arabic powder showed better stability against proteases.

Intracellular trafficking of the β-secretase and processing of amyloid precursor protein.

PubMed

Zhi, Pei; Chia, Pei Zhi Cheryl; Chia, Cheryl; Gleeson, Paul A

2011-09-01

The main component of the amyloid plaques found in the brains of those with Alzheimer's disease (AD) is a polymerized form of the β-amyloid peptide (Aβ) and is considered to play a central role in the pathogenesis of this neurodegenerative disorder. Aβ is derived from the proteolytic processing of the amyloid precursor protein (APP). Beta site APP-cleaving enzyme, BACE1 (also known as β-secretase) is a membrane-bound aspartyl protease responsible for the initial step in the generation of Aβ peptide and is thus a prime target for therapeutic intervention. Substantive evidence now indicates that the processing of APP by BACE1 is regulated by the intracellular sorting of the enzyme and, moreover, perturbations in these intracellular trafficking pathways have been linked to late-onset AD. In this review, we highlight the recent advances in the understanding of the regulation of the intracellular sorting of BACE1 and APP and illustrate why the trafficking of these cargos represent a key issue for understanding the membrane-mediated events associated with the generation of the neurotoxic Aβ products in AD. Copyright © 2011 International Union of Biochemistry and Molecular Biology, Inc.

Role of Tim50 in the Transfer of Precursor Proteins from the Outer to the Inner Membrane of Mitochondria

PubMed Central

Sichting, Martin; Popov-Čeleketić, Dušan; Mapa, Koyeli; Gevorkyan-Airapetov, Lada; Zohary, Keren; Hell, Kai; Azem, Abdussalam

2009-01-01

Transport of essentially all matrix and a number of inner membrane proteins is governed, entirely or in part, by N-terminal presequences and requires a coordinated action of the translocases of outer and inner mitochondrial membranes (TOM and TIM23 complexes). Here, we have analyzed Tim50, a subunit of the TIM23 complex that is implicated in transfer of precursors from TOM to TIM23. Tim50 is recruited to the TIM23 complex via Tim23 in an interaction that is essentially independent of the rest of the translocase. We find Tim50 in close proximity to the intermembrane space side of the TOM complex where it recognizes both types of TIM23 substrates, those that are to be transported into the matrix and those destined to the inner membrane, suggesting that Tim50 recognizes presequences. This function of Tim50 depends on its association with TIM23. We conclude that the efficient transfer of precursors between TOM and TIM23 complexes requires the concerted action of Tim50 with Tim23. PMID:19144822

Role of Tim50 in the transfer of precursor proteins from the outer to the inner membrane of mitochondria.

PubMed

Mokranjac, Dejana; Sichting, Martin; Popov-Celeketić, Dusan; Mapa, Koyeli; Gevorkyan-Airapetov, Lada; Zohary, Keren; Hell, Kai; Azem, Abdussalam; Neupert, Walter

2009-03-01

Transport of essentially all matrix and a number of inner membrane proteins is governed, entirely or in part, by N-terminal presequences and requires a coordinated action of the translocases of outer and inner mitochondrial membranes (TOM and TIM23 complexes). Here, we have analyzed Tim50, a subunit of the TIM23 complex that is implicated in transfer of precursors from TOM to TIM23. Tim50 is recruited to the TIM23 complex via Tim23 in an interaction that is essentially independent of the rest of the translocase. We find Tim50 in close proximity to the intermembrane space side of the TOM complex where it recognizes both types of TIM23 substrates, those that are to be transported into the matrix and those destined to the inner membrane, suggesting that Tim50 recognizes presequences. This function of Tim50 depends on its association with TIM23. We conclude that the efficient transfer of precursors between TOM and TIM23 complexes requires the concerted action of Tim50 with Tim23.

Effect of different concentrations of egg yolk and virgin coconut oil in Tris-based extenders on chilled and frozen-thawed bull semen.

PubMed

Tarig, A A; Wahid, H; Rosnina, Y; Yimer, N; Goh, Y M; Baiee, F H; Khumran, A M; Salman, H; Ebrahimi, M

2017-07-01

The aim of this study was to evaluate the effects of 8% virgin coconut oil (VCO) combined with different percentages of egg yolk in Tris extender on the quality of chilled and frozen-thawed bull semen. A total of 24 ejaculates from four bulls were collected using an electroejaculator. Semen samples were diluted with 8% VCO in Tris extender which contained different concentrations 0% (control), 4%, 8%, 12%, 16% and 20% egg yolk. The diluted semen samples were divided into two fractions: one was chilled and stored at 4°C until evaluation after 24, 72, and 144h; the second fraction was processed by chilling for 3h at 4°C to equilibrate, then packaged in 0.25ml straws and frozen and stored in liquid nitrogen at -196°C until evaluation after 7 and 14 days. Both chilled and frozen semen samples were then thawed at 37°C and assessed for general motility using computer-assisted semen analysis (CASA), viability, acrosome integrity, and morphology (eosin-nigrosin), membrane integrity (hypo-osmotic swelling test) and lipid peroxidation (thiobarbituric acid-reactive substances (TBARS)). The results indicate treatments with 8%, 12%, 16% and 20% egg yolk with 8% VCO had greater sperm quality (P<0.05) as compared with the control. The treatment with 20% egg yolk had the greatest sperm quality (P<0.05) among the treated groups for both chilled and frozen-thawed semen. In conclusion, the use of 8% VCO combined with 20% egg yolk in a Tris-based extender enhanced the values for chilled and frozen-thawed quality variables of bull sperm. Copyright © 2017 Elsevier B.V. All rights reserved.

Architecture engineering toward highly active palladium integrated titanium dioxide yolk-double-shell nanoreactor for catalytic applications.

PubMed

Liu, Baocang; Wang, Qin; Yu, Shengli; Jing, Peng; Liu, Lixia; Xu, Guangran; Zhang, Jun

2014-10-21

Rational design of the hierarchical architecture of a material with well controlled functionality is crucially important for improving its properties. In this paper, we present the general strategies for rationally designing and constructing three types of hierarchical Pd integrated TiO2 double-shell architectures, i.e. yolk-double-shell TiO2 architecture (Pd@TiO2/Pd@TiO2) with yolk-type Pd nanoparticles residing inside the central cavity of the hollow TiO2 structure; ultrafine Pd nanoparticles homogenously dispersed on both the external and internal surfaces of the inner TiO2 shell; and double-shell TiO2 architecture (@TiO2/Pd@TiO2) with Pd nanoparticles solely loaded on the external surface of the inner TiO2 shell, and double-shell TiO2 architecture (@TiO2@Pd@TiO2) with Pd nanoparticles dispersed in the interlayer space of double TiO2 shells, via newly developed Pd(2+) ion-diffusion and Pd sol impregnation methodologies. These architectures are well controlled in structure, size, morphology, and configuration with Pd nanoparticles existing in various locations. Owing to the variable synergistic effects arising from the location discrepancies of Pd nanoparticle in the architectures, they exhibit remarkable variations in catalytic activity. In particular, different from previously reported yolk-shell structures, the obtained yolk-double-shell Pd@TiO2/Pd@TiO2 architecture, which is revealed for the first time, possesses a uniform hierarchical structure, narrow size distribution, and good monodispersibility, and it creates two Pd-TiO2 interfaces on the external and internal surfaces of the inner TiO2 shell, leading to the strongest synergistic effect of Pd nanoparticles with TiO2 shell. Furthermore, the interlayer chamber between the double TiO2 shells connecting with the central cavity of the hollow TiO2 structure through the mesoporous TiO2 wall forms a nanoreactor for enriching the reactants and preventing the deletion of Pd nanoparticles during the reaction, thus

Molecular characteristics of insect vitellogenins and vitellogenin receptors.

PubMed

Sappington, T W; Raikhel, A S

1998-01-01

The recent cloning and sequencing of several insect vitellogenins (Vg), the major yolk protein precursor of most oviparous animals, and the mosquito Vg receptor (VgR) has brought the study of insect vitellogenesis to a new plane. Insect Vgs are homologous to nematode and vertebrate Vgs. All but one of the insect Vgs for which we know the primary structure are cleaved into two subunits at a site [(R/K)X(R/K)R or RXXR with an adjacent beta-turn] recognized by subtilisin-like proprotein convertases. In four of the Vgs, the cleavage site is near the N-terminus, but in one insect species, it is near the C-terminus of the Vg precursor. Multiple alignments of these Vg sequences indicate that the variation in cleavage location has not arisen through exon shuffling, but through local modifications of the amino acid sequences. A wasp Vg precursor is not cleaved, apparently because the sequence at the presumed ancestral cleavage site has been mutated from RXRR to LYRR and is no longer recognized by convertases. Some insect Vgs contain polyserine domains which are reminiscent of, but not homologous to, the phosvitin domain in vertebrate Vgs. The sequence of the mosquito VgR revealed that it is a member of the low-density lipoprotein receptor (LDLR) family. Though resembling chicken and frog VgRs, which are also members of the LDLR family, it is twice as big, carrying two clusters of cysteine-rich complement-type (Class A) repeats (implicated in ligand-binding) instead of one like vertebrate VgRs and LDLRs. It is very similar in sequence and domain arrangement to the Drosophila yolk protein receptor (YPR), despite a non-vitellogenin ligand for the latter. Though vertebrate VgRs, insect VgR/YPRs, and LDLR-related proteins/megalins all accommodate one cluster of eight Class A repeats, fingerprint analysis of the repeats in these clusters indicate they are not directly homologous with one another, but have undergone differing histories of duplications, deletions, and exon

Spatial and Temporal Resolution of Global Protein Synthesis during HSV Infection Using Bioorthogonal Precursors and Click Chemistry

PubMed Central

Serwa, Remigiusz A.; O’Hare, Peter

2016-01-01

We used pulse-labeling with the methionine analogue homopropargylglycine (HPG) to investigate spatiotemporal aspects of protein synthesis during herpes simplex virus (HSV) infection. In vivo incorporation of HPG enables subsequent selective coupling of fluorochrome-capture reagents to newly synthesised proteins. We demonstrate that HPG labeling had no effect on cell viability, on accumulation of test early or late viral proteins, or on overall virus yields. HPG pulse-labeling followed by SDS-PAGE analysis confirmed incorporation into newly synthesised proteins, while parallel processing by in situ cycloaddition revealed new insight into spatiotemporal aspects of protein localisation during infection. A striking feature was the rapid accumulation of newly synthesised proteins not only in a general nuclear pattern but additionally in newly forming sub-compartments represented by small discrete foci. These newly synthesised protein domains (NPDs) were similar in size and morphology to PML domains but were more numerous, and whereas PML domains were progressively disrupted, NPDs were progressively induced and persisted. Immediate-early proteins ICP4 and ICP0 were excluded from NPDs, but using an ICP0 mutant defective in PML disruption, we show a clear spatial relationship between NPDs and PML domains with NPDs frequently forming immediately adjacent and co-joining persisting PML domains. Further analysis of location of the chaperone Hsc70 demonstrated that while NPDs formed early in infection without overt Hsc70 recruitment, later in infection Hsc70 showed pronounced recruitment frequently in a coat-like fashion around NPDs. Moreover, while ICP4 and ICP0 were excluded from NPDs, ICP22 showed selective recruitment. Our data indicate that NPDs represent early recruitment of host and viral de novo translated protein to distinct structural entities which are precursors to the previously described VICE domains involved in protein quality control in the nucleus, and reveal

Evaluation of suspension array analysis for detection of egg yolk antibodies against Salmonella Enteritidis.

PubMed

Thomas, M E; Klinkenberg, D; Bergwerff, A A; van Eerden, E; Stegeman, J A; Bouma, A

2010-06-01

Salmonella enterica serovar Enteritidis (SE) is an important source of food-related diarrhoea in humans, and table eggs are considered the primordial source of contamination of the human food chain. Using eggs collected at egg-packing stations as samples could be a convenient strategy to detect colonization of layer flocks. The aim of this study was to evaluate egg yolk anti-Salmonella antibody detection using suspension array analysis. An egg yolk panel from contact-infected and non-colonized laying hens was used for the evaluation. Receiver Operating Characteristic (ROC) curves were generated to define a cut-off value and to assess the overall accuracy of the assay. The diagnostic sensitivity and specificity were estimated by maximum likelihood. Sensitivity was quantified on hen level and on sample level, and also quantified as a function of time since colonization. The area under the ROC curve was estimated at 0.984 (se 0.006, P<0.001). Of all colonized contact-infected hens, 67.6% [95% CI: 46.8, 100] developed an antibody response, which was detectable 17.4 days [14.3, 26.9] after colonization. In total, 98% [95.4, 99.4] of the 'immunopositive' hens had test positive eggs. The overall sensitivity of the immunological test was 66.7% [45.9, 98.7] and the specificity was 98.5% [97.8, 99.1]. This study provided essential parameters for optimizing surveillance programs based on detection of antibodies, and indicates that immunology based on examination of egg yolk gives important information about the Salmonella status of the flock. (c) 2010 Elsevier B.V. All rights reserved.

Consequences of inhibiting amyloid precursor protein processing enzymes on synaptic function and plasticity.

PubMed

Wang, Hui; Megill, Andrea; He, Kaiwen; Kirkwood, Alfredo; Lee, Hey-Kyoung

2012-01-01

Alzheimer's disease (AD) is a neurodegenerative disease, one of whose major pathological hallmarks is the accumulation of amyloid plaques comprised of aggregated β-amyloid (Aβ) peptides. It is now recognized that soluble Aβ oligomers may lead to synaptic dysfunctions early in AD pathology preceding plaque deposition. Aβ is produced by a sequential cleavage of amyloid precursor protein (APP) by the activity of β- and γ-secretases, which have been identified as major candidate therapeutic targets of AD. This paper focuses on how Aβ alters synaptic function and the functional consequences of inhibiting the activity of the two secretases responsible for Aβ generation. Abnormalities in synaptic function resulting from the absence or inhibition of the Aβ-producing enzymes suggest that Aβ itself may have normal physiological functions which are disrupted by abnormal accumulation of Aβ during AD pathology. This interpretation suggests that AD therapeutics targeting the β- and γ-secretases should be developed to restore normal levels of Aβ or combined with measures to circumvent the associated synaptic dysfunction(s) in order to have minimal impact on normal synaptic function.

Amyloid precursor protein expression and processing are differentially regulated during cortical neuron differentiation.

PubMed

Bergström, Petra; Agholme, Lotta; Nazir, Faisal Hayat; Satir, Tugce Munise; Toombs, Jamie; Wellington, Henrietta; Strandberg, Joakim; Bontell, Thomas Olsson; Kvartsberg, Hlin; Holmström, Maria; Boreström, Cecilia; Simonsson, Stina; Kunath, Tilo; Lindahl, Anders; Blennow, Kaj; Hanse, Eric; Portelius, Erik; Wray, Selina; Zetterberg, Henrik

2016-07-07

Amyloid precursor protein (APP) and its cleavage product amyloid β (Aβ) have been thoroughly studied in Alzheimer's disease. However, APP also appears to be important for neuronal development. Differentiation of induced pluripotent stem cells (iPSCs) towards cortical neurons enables in vitro mechanistic studies on human neuronal development. Here, we investigated expression and proteolytic processing of APP during differentiation of human iPSCs towards cortical neurons over a 100-day period. APP expression remained stable during neuronal differentiation, whereas APP processing changed. α-Cleaved soluble APP (sAPPα) was secreted early during differentiation, from neuronal progenitors, while β-cleaved soluble APP (sAPPβ) was first secreted after deep-layer neurons had formed. Short Aβ peptides, including Aβ1-15/16, peaked during the progenitor stage, while processing shifted towards longer peptides, such as Aβ1-40/42, when post-mitotic neurons appeared. This indicates that APP processing is regulated throughout differentiation of cortical neurons and that amyloidogenic APP processing, as reflected by Aβ1-40/42, is associated with mature neuronal phenotypes.

The intact Kunitz domain protects the amyloid precursor protein from being processed by matriptase-2.

PubMed

Beckmann, Anna-Madeleine; Glebov, Konstantin; Walter, Jochen; Merkel, Olaf; Mangold, Martin; Schmidt, Frederike; Becker-Pauly, Christoph; Gütschow, Michael; Stirnberg, Marit

2016-08-01

Proteolytic processing of the amyloid precursor protein (APP) leads to amyloid-β (Aβ) peptides. So far, the mechanism of APP processing is insufficiently characterized at the molecular level. Whereas the knowledge of Aβ generation by several proteases has been expanded, the contribution of the Kunitz-type protease inhibitor domain (KPI) present in two major APP isoforms to the complex proteolytic processing of APP is poorly understood. In this study, we have identified KPI-containing APP as a very potent, slow-binding inhibitor for the membrane-bound proteolytic regulator of iron homeostasis matriptase-2 by forming stable complexes with its target protease in HEK cells. Inhibition and complex formation depend on the intact KPI domain. By inhibiting matriptase-2, KPI-containing APP is protected from matriptase-2-mediated proteolysis within the Aβ region, thus preventing the generation of N-terminally truncated Aβ.

CSF soluble amyloid precursor proteins in the diagnosis of incipient Alzheimer disease.

PubMed

Perneczky, R; Tsolakidou, A; Arnold, A; Diehl-Schmid, J; Grimmer, T; Förstl, H; Kurz, A; Alexopoulos, P

2011-07-05

To explore if soluble amyloid precursor proteins (sAPP) in CSF improve the identification of patients with incipient Alzheimer disease (AD) in a group of patients with mild cognitive impairment (MCI). A cohort study with follow-up assessments of 58 patients with MCI with baseline CSF sampling was conducted: 21 patients had progressed to probable AD (MCI-AD), 27 still had MCI, 8 had reverted to normal (MCI-NAD), and 2 patients with frontotemporal dementia (FTD) were excluded. Sixteen additional patients with FTD were included to explore the specificity of the CSF markers. CSF concentrations of sAPPα, sAPPβ, tau, and Aβ(1-42) were measured with sensitive and specific ELISAs. Associations between diagnostic status, CSF protein concentrations, and other patient characteristics were explored using multiple logistic regression analyses with stepwise variable selection. The optimal sensitivity and specificity of the best models were derived from receiver operating characteristic curves. The MCI-AD group had significantly higher sAPPβ concentrations than the MCI-NAD and the FTD groups. A combination of sAPPβ, tau, and age differentiated the MCI-AD and the MCI-NAD groups with a sensitivity of 80.00% and a specificity of 81.00%. The best model for the differentiation of the MCI-AD and the FTD groups included sAPPβ and tau, and showed a sensitivity of 95.20% and a specificity of 81.20%. Aβ(1-42) and sAPPα did not significantly contribute to the models. These findings suggest that sAPPβ may be clinically useful, and superior to Aβ(1-42), in the early and differential diagnosis of incipient AD.

NiO/NiWO4 Composite Yolk-Shell Spheres with Nanoscale NiO Outer Layer for Ultrasensitive and Selective Detection of Subppm-level p-Xylene.

PubMed

Kim, Tae-Hyung; Kwak, Chang-Hoon; Lee, Jong-Heun

2017-09-20

NiO/NiWO 4 composite yolk-shell spheres with a nanoscale NiO outer layer were prepared using one-pot ultrasonic spray pyrolysis and their gas sensing characteristics were studied. The NiO/NiWO 4 yolk-shell spheres exhibited an extremely high response to 5 ppm p-xylene (ratio of resistance to gas and air = 343.5) and negligible cross-responses to 5 ppm ethanol, ammonia, carbon monoxide, hydrogen, and benzene, whereas pure NiO yolk-shell spheres showed very low responses and selectivity to all the analyte gases. The detection limit for p-xylene was as low as 22.7 ppb. This ultrasensitive and selective detection of p-xylene is attributed to a synergistic catalytic effect between NiO and NiWO 4 , high gas accessibility with large specific surface area, and increased chemiresistive variation due to the formation of a heterojunction. The NiO/NiWO 4 yolk-shell spheres with a thin NiO outer layer can be used to detect subppm-level p-xylene in a highly sensitive and selective manner for monitoring indoor air pollution.

A recombinant pseudorabies virus co-expressing capsid proteins precursor P1-2A of FMDV and VP2 protein of porcine parvovirus: a trivalent vaccine candidate.

PubMed

Hong, Qi; Qian, Ping; Li, Xiang-Min; Yu, Xiao-Lan; Chen, Huan-Chun

2007-11-01

Pseudorabies (PR), foot-and-mouth disease (FMD), and porcine parvovirus disease are three important infectious diseases in swine worldwide. The gene-deleted pseudorabies virus (PRV) has been used as a live-viral vector to develop multivalent genetic engineering vaccine. In this study, a recombinant PRV, which could co-express protein precursor P1-2A of FMDV and VP2 protein of PPV, was constructed using PRV TK(-)/gE(-)/LacZ(+) mutant as the vector. After homologous recombination and plaque purification, recombinant virus PRV TK(-)/gE(-)/P1-2A-VP2 was acquired and identified. Immunogenicity, safety of the recombinant PRV and its protection against PRV were confirmed in a mouse model by indirect ELISA and serum neutralization test. The results show that the recombinant PRV is a candidate vaccine strain to develop a novel trivalent vaccine against PRV, FMDV and PPV in swine.

Yolk-like Fe3O4@C-Au@void@TiO2-Pd hierarchical microspheres with visible light-assisted enhanced photocatalytic degradation of dye

NASA Astrophysics Data System (ADS)

Chen, Suqing; Liang, Huading; Shen, Mao; Jin, Yanxian

2018-04-01

In this paper, we present the design and implementation of a type of yolk-like Fe3O4@C-Au@void@TiO2-Pd hierarchical microspheres with visible light-assisted enhanced photocatalytic degradation of dye and rapid magnetic separation. The resulting composite microspheres exhibited yolk-like hierarchical structures with a 236.3 m2 g-1 surface area and a high-saturation magnetization of 31.5 emu g-1. As an example of applications, the photodegradation of Rhodamine B (RhB) in the presence of NaBH4 was investigated under simulated sunlight irradiation. The results show that the photocatalytic activity of the yolk-like Fe3O4@C-Au@void@TiO2-Pd microcomposites in the RhB photodegradation is higher than the Fe3O4@C-Au@void@TiO2 and Fe3O4@C@TiO2 microcomposites, as they can degrade RhB with 40 min of irradiation time. In addition, by magnetic separation, the as-prepared yolk-like Fe3O4@C-Au@void@TiO2-Pd hierarchical microcomposites can be completely separated and reused for four times.

Identification of a novel amyloid precursor protein processing pathway that generates secreted N-terminal fragments.

PubMed

Vella, Laura J; Cappai, Roberto

2012-07-01

Alzheimer's disease (AD) is a neurodegenerative disorder of the central nervous system. The proteolytic processing of the amyloid precursor protein (APP) into the β-amyloid (Aβ) peptide is a central event in AD. While the pathway that generates Aβ is well described, many questions remain concerning general APP metabolism and its metabolites. It is becoming clear that the amino-terminal region of APP can be processed to release small N-terminal fragments (NTFs). The purpose of this study was to investigate the occurrence and generation of APP NTFs in vivo and in cell culture (SH-SY5Y) in order to delineate the cellular pathways implicated in their generation. We were able to detect 17- to 28-kDa APP NTFs in human and mouse brain tissue that are distinct from N-APP fragments previously reported. We show that the 17- to 28-kDa APP NTFs were highly expressed in mice from the age of 2 wk to adulthood. SH-SY5Y studies indicate the generation of APP NTFs involves a novel APP processing pathway, regulated by protein kinase C, but independent of α-secretase or β-secretase 1 (BACE) activity. These results identify a novel, developmentally regulated APP processing pathway that may play an important role in the physiological function of APP.

Lactose-egg yolk diluent supplemented with N-acetyl-D-glucosamine affect acrosome morphology and motility of frozen-thawed boar sperm.

PubMed

Yi, Y J; Im, G S; Park, C S

2002-12-16

These experiments were carried out to investigate the effect of N-acetyl-D-glucosamine, and to obtain additional information about the effect of orvus es paste (OEP) and egg yolk concentration in the freezing of boar sperm in the maxi-straw. The highest post-thaw acrosomes of normal apical ridge (NAR) and motility were obtained with 0.025 or 0.05% N-acetyl-D-glucosamine concentration in the first diluent. However, there were no effects of N-acetyl-D-glucosamine among the diluents with or without N-acetyl-D-glucosamine at the second dilution. The N-acetyl-D-glucosamine in the first and second diluents was added at room temperatures (20-23 degrees C) and 5 degrees C, respectively. It is suggested that the temperature of N-acetyl-D-glucosamine addition is important for the effect of boar sperm protection during freezing and thawing. When the 0.05% N-acetyl-D-glucosamine was supplemented in the first diluent, the optimum final OEP content was 0.5%. The optimum content of egg yolk in the diluent with 0.05% N-acetyl-D-glucosamine concentration was 20% and egg yolk was one of the main cryoprotective agents. In conclusion, we found out that the diluent with 0.025 or 0.05% soluble N-acetyl-D-glucosamine in the first diluent, 0.5% final orvus es paste concentration and 20% egg yolk concentration significantly enhanced NAR acrosomes and motility of boar sperm after freezing and thawing. Copyright 2002 Elsevier Science B.V.

The h-region of twin-arginine signal peptides supports productive binding of bacterial Tat precursor proteins to the TatBC receptor complex.

PubMed

Ulfig, Agnes; Fröbel, Julia; Lausberg, Frank; Blümmel, Anne-Sophie; Heide, Anna Katharina; Müller, Matthias; Freudl, Roland

2017-06-30

The twin-arginine translocation (Tat) pathway transports folded proteins across bacterial membranes. Tat precursor proteins possess a conserved twin-arginine (RR) motif in their signal peptides that is involved in their binding to the Tat translocase, but some facets of this interaction remain unclear. Here, we investigated the role of the hydrophobic (h-) region of the Escherichia coli trimethylamine N -oxide reductase (TorA) signal peptide in TatBC receptor binding in vivo and in vitro We show that besides the RR motif, a minimal, functional h-region in the signal peptide is required for Tat-dependent export in Escherichia coli Furthermore, we identified mutations in the h-region that synergistically suppressed the export defect of a TorA[KQ]-30aa-MalE Tat reporter protein in which the RR motif was replaced with a lysine-glutamine pair. Strikingly, all suppressor mutations increased the hydrophobicity of the h-region. By systematically replacing a neutral residue in the h-region with various amino acids, we detected a positive correlation between the hydrophobicity of the h-region and the translocation efficiency of the resulting reporter variants. In vitro cross-linking of residues located in the periplasmically-oriented part of the TatBC receptor to TorA[KQ]-30aa-MalE reporter variants harboring a more hydrophobic h-region in their signal peptides confirmed that unlike in TorA[KQ]-30aa-MalE with an unaltered h-region, the mutated reporters moved deep into the TatBC-binding cavity. Our results clearly indicate that, besides the Tat motif, the h-region of the Tat signal peptides is another important binding determinant that significantly contributes to the productive interaction of Tat precursor proteins with the TatBC receptor complex. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Effect of marine by-product meals on hen egg production parameters, yolk lipid composition and sensory quality.

PubMed

Toyes-Vargas, E; Ortega-Pérez, R; Espinoza-Villavicencio, J L; Arellano-Pérez, M; Civera, R; Palacios, E

2018-04-01

The effect of including 5% marine by-product meals in feeds of laying hens on egg production, composition and sensory characteristics was tested. Marine by-product meals were prepared using two methods: (i) cooking (100°C/10 min) followed by drying (60°C/24 hr) or (ii) grinding followed by drying. The raw materials used for meal production were scallop or squid viscera, shrimp heads or whole mackerel. A total of 108 laying hens were allocated to nine diet treatments; one control diet (corn and soya bean based) and eight experimental diets, containing 95% of the control feed and 5% of the experimental meal for three weeks. Daily intake was higher in hens fed the dried mackerel and cooked shrimp meals. All the experimental treatments showed significantly higher concentration of n-3 HUFA in yolk reserves and phospholipids compared to the control (0.12-0.13 g per 100 g), especially those with scallop or squid prepared by both methods (0.53-0.95 g per 100 g). Scallop, squid and shrimp meal inclusion in the feed produced eggs with more astaxanthin (0.22 mg per 100 g) while this carotenoid was absent in the control and mackerel treatments. Visual evaluation of raw yolk colour increased with the inclusion of marine by-product meals with higher values in hens fed shrimp heads (13), followed by scallop viscera (11), squid viscera (9), and with similar values for mackerel and control (4). The taste, aroma, texture and colour of cooked eggs from different treatments were not statically different when evaluated by a panel of 60 untrained people. These results suggest that meals from marine by-products are a better alternative for improving egg yolk composition by increasing n-3 HUFA when compared to fishmeal as they also increase astaxanthin and yolk pigmentation without affecting egg sensory characteristics. © 2017 Blackwell Verlag GmbH.

Establishment of the fatty acid profile of the brain of the king penguin (Aptenodytes patagonicus) at hatch: effects of a yolk that is naturally rich in n-3 polyunsaturates.

PubMed

Speake, Brian K; Decrock, Frederic; Surai, Peter F; Wood, Nicholas A R; Groscolas, René

2003-01-01

Because the yolk lipids of the king penguin (Aptenodytes patagonicus) contain the highest concentrations of long-chain n-3 polyunsaturated fatty acids yet reported for an avian species, the consequences for the establishment of the brain's fatty acid profile in the embryo were investigated. To place the results in context, the fatty acid compositions of yolk lipid and brain phospholipid of the king penguin were compared with those from three other species of free-living birds. The proportions of docosahexaenoic acid (22:6n-3; DHA) in the total lipid of the initial yolks for the Canada goose (Branta canadensis), mallard (Anas platyrhynchos), moorhen (Gallinula chloropus), and king penguin were (% w/w of fatty acids) 1.0+/-0.1, 1.9+/-0.2, 3.3+/-0.1, and 5.9+/-0.2, respectively. The respective concentrations of DHA (% w/w of phospholipid fatty acids) in brains of the newly hatched chicks of these same species were 18.5+/-0.2, 19.6+/-0.7, 16.9+/-0.4, and 17.6+/-0.1. Thus, the natural interspecies diversity in yolk fatty acid profiles does not necessarily produce major differences in the DHA content of the developing brain. Only about 1% of the amount of DHA initially present in the yolk was recovered in the brain of the penguin at hatch. There was no preferential uptake of DHA from the yolk during development of the king penguin.

Maternally derived egg hormones, antibodies and antimicrobial proteins: common and different pathways of maternal effects in Japanese quail.

PubMed

Okuliarova, Monika; Kankova, Zuzana; Bertin, Aline; Leterrier, Christine; Mostl, Erich; Zeman, Michal

2014-01-01

Avian eggs contain a variety of maternally-derived substances that can influence the development and performance of offspring. The levels of these egg compounds vary in relation to environmental and genetic factors, but little is known about whether there are correlative links between maternal substances in the egg underlying common and different pathways of maternal effects. In the present study, we investigated genetically determined variability and mutually adjusted deposition of sex hormones (testosterone-T, androstenedione-A4 and progesterone-P4), antibodies (IgY) and antimicrobial proteins (lysozyme) in eggs of Japanese quail (Coturnix japonica). We used different genetic lines that were independently selected for yolk T concentrations, duration of tonic immobility and social reinstatement behaviour, since both selections for behavioural traits (fearfulness and social motivation, respectively) produced considerable correlative responses in yolk androgen levels. A higher selection potential was found for increased rather than decreased yolk T concentrations, suggesting that there is a physiological minimum in egg T levels. Line differences in yolk IgY concentrations were manifested within each selection experiment, but no consistent inter-line pattern between yolk IgY and T was revealed. On the other hand, a consistent inverse inter-line pattern was recorded between yolk IgY and P4 in both selections for behavioural traits. In addition, selections for contrasting fearfulness and social motivation were associated with changes in albumen lysozyme concentrations and an inverse inter-line pattern between the deposition of yolk IgY and albumen lysozyme was found in lines selected for the level of social motivation. Thus, our results demonstrate genetically-driven changes in deposition of yolk T, P4, antibodies and albumen lysozyme in the egg. This genetic variability can partially explain mutually adjusted maternal deposition of sex hormones and immune

Preparation of immunoglobulin Y from egg yolk using ammonium sulfate precipitation and ion exchange chromatography.

PubMed

Ko, K Y; Ahn, D U

2007-02-01

The objective of this study was to develop an economical, simple, and large-scale separation method for IgY from egg yolk. Egg yolk diluted with 9 volumes of cold water was centrifuged after adjusting the pH to 5.0. The supernatant was added with 0.01% charcoal or 0.01% carrageenan and centrifuged at 2,800 x g for 30 min. The supernatant was filtered through a Whatman no. 1 filter paper and then the filtrate was concentrated to 20% original volume using ultrafiltration. The concentrated solution was further purified using either cation exchange chromatography or ammonium sulfate precipitation. For the cation exchange chromatography method, the concentrated sample was loaded onto a column equilibrated with 20 mM citrate-phosphate buffer at pH 4.8 and eluted with 200 mM citrate-phosphate buffer at pH 6.4. For the ammonium sulfate precipitation method, the concentrated sample was twice precipitated with 40% ammonium sulfate solution at pH 9.0. The yield and purity of IgY were determined by ELISA and electrophoresis. The yield of IgY from the cation exchange chromatography method was 30 to 40%, whereas that of the ammonium sulfate precipitation was 70 to 80%. The purity of IgY from the ammonium sulfate method was higher than that of the cation exchange chromatography. The cation exchange chromatography could handle only a small amount of samples, whereas the ammonium sulfate precipitation could handle a large volume of samples. This suggests that ammonium sulfate precipitation was a more efficient and useful purification method than cation exchange chromatography for the large-scale preparation of IgY from egg yolk.

Embryo yolk sac membrane kynurenine formamidase of l-tryptophan to NAD+ pathway as a primary target for organophosphorus insecticides (OPI) in OPI-induced NAD-associated avian teratogenesis.

PubMed

Seifert, Josef

2017-10-01

The objective of this study was to provide in ovo evidence for the proposed role of kynurenine formamidase of l-tryptophan to NAD + pathway in embryo yolk sac membranes as a primary target for organophosphorus insecticide (OPI) teratogens in OPI-induced NAD-associated avian teratogenesis. Slices prepared from yolk sac membranes or embryo livers of chicken eggs treated with the OPI dicrotophos and/or methyl parathion were incubated with l-tryptophan. Yolk sac membrane slices metabolized l-tryptophan in the pathway to NAD + before that function was established in livers. OPI interfered in ovo with the second step of l-tryptophan to NAD + biosynthesis by inhibiting kynurenine formamidase. Its inhibition due to the teratogen dicrotophos occurred in yolk sac membranes during the period of embryo highest susceptibility to OPI teratogens in contrast to delayed and lower inhibition caused by the nonteratogen methyl parathion. Both OPI affected liver kynurenine formamidase in a similar manner. The onsets of liver enzyme inhibition, however, were delayed by about two days and occurred at the time of the reduced embryo susceptibility to teratogens. The early disruption of l-tryptophan metabolism and higher inhibition of kynurenine formamidase in yolk sac membranes may be the factors that determine action of OPI as teratogens in chicken embryos. Copyright © 2017 Elsevier Ltd. All rights reserved.

Specific Inhibition of β-Secretase Processing of the Alzheimer Disease Amyloid Precursor Protein.

PubMed

Ben Halima, Saoussen; Mishra, Sabyashachi; Raja, K Muruga Poopathi; Willem, Michael; Baici, Antonio; Simons, Kai; Brüstle, Oliver; Koch, Philipp; Haass, Christian; Caflisch, Amedeo; Rajendran, Lawrence

2016-03-08

Development of disease-modifying therapeutics is urgently needed for treating Alzheimer disease (AD). AD is characterized by toxic β-amyloid (Aβ) peptides produced by β- and γ-secretase-mediated cleavage of the amyloid precursor protein (APP). β-secretase inhibitors reduce Aβ levels, but mechanism-based side effects arise because they also inhibit β-cleavage of non-amyloid substrates like Neuregulin. We report that β-secretase has a higher affinity for Neuregulin than it does for APP. Kinetic studies demonstrate that the affinities and catalytic efficiencies of β-secretase are higher toward non-amyloid substrates than toward APP. We show that non-amyloid substrates are processed by β-secretase in an endocytosis-independent manner. Exploiting this compartmentalization of substrates, we specifically target the endosomal β-secretase by an endosomally targeted β-secretase inhibitor, which blocked cleavage of APP but not non-amyloid substrates in many cell systems, including induced pluripotent stem cell (iPSC)-derived neurons. β-secretase inhibitors can be designed to specifically inhibit the Alzheimer process, enhancing their potential as AD therapeutics without undesired side effects. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Comparative Protein Profiling of Intraphagosomal Expressed Proteins of Mycobacterium bovis BCG.

PubMed

Singhal, Neelja; Kumar, Manish; Sharma, Divakar; Bisht, Deepa

2016-01-01

BCG, the only available vaccine against tuberculosis affords a variable protection which wanes with time. In this study we have analyzed and compared the proteins which are expressed differentially during broth-culture and intraphagosomal growth of M.bovis BCG. Eight proteins which showed increased expression during the intraphagosomal growth were identified by MALDI-TOF/MS. These were - a precursor of alanine and proline-rich secreted protein apa, isoforms of malate dehydrogenase, large subunit alpha (Alpha-ETF) of electron transfer flavoprotein, immunogenic protein MPB64 precursor, UPF0036 protein, and two proteins with unknown function. Based on these findings we speculate that higher expression of these proteins has a probable role in intracellular survival, adaptation and/or immunoprotective effect of BCG. Further, these proteins might also be used as gene expression markers for endosome trafficking events of BCG.

The Preparation of Au@TiO2 Yolk-Shell Nanostructure and its Applications for Degradation and Detection of Methylene Blue

NASA Astrophysics Data System (ADS)

Wan, Gengping; Peng, Xiange; Zeng, Min; Yu, Lei; Wang, Kan; Li, Xinyue; Wang, Guizhen

2017-09-01

This paper reports the synthesis of a new type of Au@TiO2 yolk-shell nanostructures by integrating ion sputtering method with atomic layer deposition (ALD) technique and its applications as visible light-driven photocatalyst and surface-enhanced Raman spectroscopy (SERS) substrate. Both the size and amount of gold nanoparticles confined in TiO2 nanotubes could be facilely controlled via properly adjusting the sputtering time. The unique structure and morphology of the resulting Au@TiO2 samples were investigated by using various spectroscopic and microscopic techniques in detail. It is found that all tested samples can absorb visible light with a maximum absorption at localized surface plasmon resonance (LSPR) wavelengths (550-590 nm) which are determined by the size of gold nanoparticles. The Au@TiO2 yolk-shell composites were used as the photocatalyst for the degradation of methylene blue (MB). As compared with pure TiO2 nanotubes, Au@TiO2 composites exhibit improved photocatalytic properties towards the degradation of MB. The SERS effect of Au@TiO2 yolk-shell composites was also performed to investigate the detection sensitivity of MB.

The Preparation of Au@TiO2 Yolk-Shell Nanostructure and its Applications for Degradation and Detection of Methylene Blue.

PubMed

Wan, Gengping; Peng, Xiange; Zeng, Min; Yu, Lei; Wang, Kan; Li, Xinyue; Wang, Guizhen

2017-09-18

This paper reports the synthesis of a new type of Au@TiO 2 yolk-shell nanostructures by integrating ion sputtering method with atomic layer deposition (ALD) technique and its applications as visible light-driven photocatalyst and surface-enhanced Raman spectroscopy (SERS) substrate. Both the size and amount of gold nanoparticles confined in TiO 2 nanotubes could be facilely controlled via properly adjusting the sputtering time. The unique structure and morphology of the resulting Au@TiO 2 samples were investigated by using various spectroscopic and microscopic techniques in detail. It is found that all tested samples can absorb visible light with a maximum absorption at localized surface plasmon resonance (LSPR) wavelengths (550-590 nm) which are determined by the size of gold nanoparticles. The Au@TiO 2 yolk-shell composites were used as the photocatalyst for the degradation of methylene blue (MB). As compared with pure TiO 2 nanotubes, Au@TiO 2 composites exhibit improved photocatalytic properties towards the degradation of MB. The SERS effect of Au@TiO 2 yolk-shell composites was also performed to investigate the detection sensitivity of MB.

Long-lasting and sex-specific consequences of elevated egg yolk testosterone for social behavior in Japanese quail.

PubMed

Schweitzer, Cécile; Goldstein, Michael H; Place, Ned J; Adkins-Regan, Elizabeth

2013-01-01

In birds, early exposure to steroid hormones deposited in egg yolks is hypothesized to result in long-lasting effects on brain and behavior. However, the long-term effects of maternal androgens on the development of social behavior, and whether these could interfere with the effects of the endogenous gonadal hormones that mediate sexual differentiation, remain poorly known. To answer these questions, we enhanced yolk testosterone by injecting testosterone (T) in oil into Japanese quail (Coturnix japonica) eggs prior to incubation. Vehicle-injected (V) eggs served as controls. From age 3 weeks to 8 weeks, sexual development was measured using morphological and physiological traits, and social behavior was measured, including male-typical sexual behavior. In females, treatment with testosterone boosted growth. Males from T-injected eggs developed an affiliative preference for familiar females and differed from V-injected males in the acoustic features of their crows, whereas sexual interest (looking behavior) and copulatory behavior were not affected. These long-lasting and sex-specific yolk testosterone effects on the development of dimorphic traits, but without disrupting sexual differentiation of reproductive behavior suggest potential organizational effects of maternal testosterone, but acting through separate processes than the endocrine mechanisms previously shown to control sexual differentiation. Separate processes could reflect the action of androgens at different times or on multiple targets that are differentially sensitive to steroids or develop at different rates. Copyright © 2012 Elsevier Inc. All rights reserved.

Enteral Nutrition With an Enteral Formula Containing Egg Yolk Lecithin After Percutaneous Endoscopic Gastrostomy: A Case Series

PubMed Central

Akashi, Tetsuro; Hashimoto, Risa; Ohno, Akihisa; Matsumoto, Kazuhide; Nakamura, Yukari

2018-01-01

The occurrence of diarrhea at the beginning of enteral nutrition complicates the continuation of enteral nutrition. Recently, studies in Japan indicated that diarrhea could be improved by changing the enteral formula to one that is emulsified with egg yolk lecithin. In this study, we administered the enteral formula K-2S plus, which is emulsified with egg yolk lecithin, to 15 patients (four men and 11 women; mean age, 79.9 ± 2.0 years) after they had undergone a percutaneous endoscopic gastrostomy (PEG) to prevent the occurrence of diarrhea related to enteral nutrition. Two days after the PEG, the patients would receive 200 mL K-2S plus intermittently three times daily; thereafter, the amount of K-2S plus was increased according to the patient’s condition. The administration rate was scheduled as 200 mL/h when 200 mL were administered at one time. For ≥ 300 mL, the scheduled administration rate was 300 mL/h. When we administered K-2S plus at the beginning of enteral nutrition after the PEG, the dose of the enteral formula could be increased without any occurrence of diarrhea or vomiting. Five patients had received intravenous nutrition before the PEG; thus, we were concerned about diarrhea in these patients. In conclusion, an enteral formula emulsified with egg yolk lecithin may be safely used at the time of enteral nutrition initiation without causing diarrhea. PMID:29707085

Inhibition of Wnt signaling induces amyloidogenic processing of amyloid precursor protein and the production and aggregation of Amyloid-β (Aβ)42 peptides.

PubMed

Tapia-Rojas, Cheril; Burgos, Patricia V; Inestrosa, Nibaldo C

2016-12-01

Alzheimer's disease (AD) is the most common neurodegenerative disorder and the most frequent cause of dementia in the aged population. According to the amyloid hypothesis, the amyloid-β (Aβ) peptide plays a key role in the pathogenesis of AD. Aβ is generated from the amyloidogenic processing of amyloid precursor protein and can aggregate to form oligomers, which have been described as a major synaptotoxic agent in neurons. Dysfunction of Wnt signaling has been linked to increased Aβ formation; however, several other studies have argued against this possibility. Herein, we use multiple experimental approaches to confirm that the inhibition of Wnt signaling promoted the amyloidogenic proteolytic processing of amyloid precursor protein. We also demonstrate that inhibiting Wnt signaling increases the production of the Aβ 42 peptide, the Aβ 42 /Aβ 40 ratio, and the levels of Aβ oligomers such as trimers and tetramers. Moreover, we show that activating Wnt signaling reduces the levels of Aβ 42 and its aggregates, increases Aβ 40 levels, and reduces the Aβ 42 /Aβ 40 ratio. Finally, we show that the protective effects observed in response to activation of the Wnt pathway rely on β-catenin-dependent transcription, which is demonstrated experimentally via the expression of various 'mutant forms of β-catenin'. Together, our findings indicate that loss of the Wnt signaling pathway may contribute to the pathogenesis of AD. © 2016 International Society for Neurochemistry.

Differentiating the Influences of Aging and Adiposity on Brain Weights, Levels of Serum and Brain Cytokines, Gastrointestinal Hormones, and Amyloid Precursor Protein.

PubMed

Banks, William A; Abrass, Christine K; Hansen, Kim M

2016-01-01

Aging and obesity exert important effects on disease. Differentiating these effects is difficult, however, because weight gain often accompanies aging. Here, we used a nested design of aged, calorically restricted, and refed rats to measure changes in brain and blood levels of cytokines and gastrointestinal hormones, brain amyloid precursor protein levels, and brain and body weights. By comparing groups and using path analysis, we found divergent influences of chronological aging versus body weight, our main findings being (i) changes in whole brain weight and serum macrophage colony-stimulating factor levels correlated better with body weight than with chronological aging, (ii) a decrease in brain cytokines and brain plasminogen activator inhibitor levels correlated better with chronological aging than with body weight, (iii) serum erythropoietin levels were influenced by both body weight and aging, (iv) serum plasminogen activator inhibitor, serum cytokines, and brain tumor necrosis factor were not influenced by aging or body weight, and (v) brain amyloid precursor protein more closely related to body weight and serum levels of gastrointestinal hormones than to brain weight, chronological aging, or cytokines. These findings show that although aging and body weight interact, their influences are distinct not only among various cytokines and hormones but also between the central nervous system and the peripheral tissue compartments. Published by Oxford University Press on behalf of the Gerontological Society of America 2014.

Amino Acid Starvation Induced by Protease Inhibition Produces Differential Alterations in Redox Status and the Thiol Proteome in Organogenesis-Stage Rat Embryos and Visceral Yolk Sacs

PubMed Central

Harris, Craig; Jilek, Joseph L.; Sant, Karilyn E.; Pohl, Jan; Reed, Matthew; Hansen, Jason M.

2015-01-01

The process of embryonic nutrition in rodent conceptuses during organogenesis has been shown to involve a dominant histiotrophic mechanism where essential developmental substrates and micronutrients are supplied as whole maternal proteins or cargoes associated with proteins. The histiotrophic nutrition pathways (HNP) responsible for uptake and initial processing of proteins across maternal-conceptal interfaces involve uptake via receptor mediated endocytosis and protein degradation via lysosomal proteolysis. Chemical inhibition of either process can lead to growth deficits and malformation in the embryo (EMB), but selective inhibition of either HNP component will elicit a different subset of developmental perturbations. In vitro, whole embryo culture (WEC) exposure of GD10 or GD11 rat conceptuses to the natural protease inhibitor, leupeptin, leads to significant reductions in all measured embryonic growth parameters as well as a myriad of other effects. Leupeptin doses of 10 μM or 20 μM over a 26 hr period (GD10-GD11) and 50 μM over a 3 hr pulse period produced significant decreases in the clearance of FITC-albumin from culture media. The near complete loss of acid soluble fluorescence and increased total visceral yolk sac (VYS) protein content confirmed the selective inhibition of proteolysis. Inhibition of lysosomal proteolysis thus deprives the developing EMB of essential nutrient amino acids producing conditions akin to amino acid starvation, but may also cause direct effects on pathways critical for normal growth and differentiation. Following leupeptin exposure for 26 or 6 hr, total glutathione (GSH) concentrations dropped significantly in the VYS, but only slightly in yolk sac (YSF) and amniotic (AF) fluids. Cys concentrations increased in VYS and EMB, but dropped in YSF and AF fluids. Redox potentials (Eh) for the GSSG/GSH redox couple trended significantly toward the positive, confirming the net oxidation of conceptual tissues following leupeptin

Amyloid Precursor-like Protein 2 Increases the Endocytosis, Instability, and Turnover of the H2-Kd MHC Class I Molecule1

PubMed Central

Tuli, Amit; Sharma, Mahak; McIlhaney, Mary M.; Talmadge, James E.; Naslavsky, Naava; Caplan, Steve; Solheim, Joyce C.

2008-01-01

The defense against the invasion of viruses and tumors relies on the presentation of viral and tumor-derived peptides to cytotoxic T lymphocytes by cell surface major histocompatibility complex (MHC) class I molecules. Previously, we showed that the ubiquitously expressed protein amyloid precursor-like protein 2 (APLP2) associates with the folded form of the MHC class I molecule Kd. In the current study, APLP2 was found to associate with folded Kd molecules following their endocytosis and to increase the amount of endocytosed Kd. In addition, increased expression of APLP2 was shown to decrease Kd surface expression and thermostability. Correspondingly, Kd thermostability and surface expression were increased by down-regulation of APLP2 expression. Overall, these data suggest that APLP2 modulates the stability and endocytosis of Kd molecules. PMID:18641335

Protein import into isolated pea root leucoplasts.

PubMed

Chu, Chiung-Chih; Li, Hsou-Min

2015-01-01

Leucoplasts are important organelles for the synthesis and storage of starch, lipids and proteins. However, molecular mechanism of protein import into leucoplasts and how it differs from that of import into chloroplasts remain unknown. We used pea seedlings for both chloroplast and leucoplast isolations to compare within the same species. We further optimized the isolation and import conditions to improve import efficiency and to permit a quantitative comparison between the two plastid types. The authenticity of the import was verified using a mitochondrial precursor protein. Our results show that, when normalized to Toc75, most translocon proteins are less abundant in leucoplasts than in chloroplasts. A precursor shown to prefer the receptor Toc132 indeed had relatively more similar import efficiencies between chloroplasts and leucoplasts compared to precursors that prefer Toc159. Furthermore we found two precursors that exhibited very high import efficiency into leucoplasts. Their transit peptides may be candidates for delivering transgenic proteins into leucoplasts and for analyzing motifs important for leucoplast import.

Primary yolk sac tumor of the urachus.

PubMed

Romero-Rojas, Alfredo Ernesto; Messa-Botero, Oscar Alberto; Melo-Uribe, Mario Alexander; Díaz-Pérez, Julio Alexander; Chinchilla-Olaya, Sandra Isabel

2011-10-01

Neoplasms originating from the urachus are rare. The most common urachal malignancy is adenocarcinoma, whereas extragonadal germ cell tumors, primarily of the urachus, are an extremely rare finding. To describe a primary yolk sac tumor (YST) of the urachus in an adult. A 44-year-old woman presented with 6 months of pelvic pain associated with a sensation of progressive mass growth. At the time of tumor resection, the tumor was found to be attached by a pedicle to the dome of the bladder, with no injury to the adjacent organs. Pathological study showed a neoplasm with epithelioid cells, pseudocysts, a myxomatous background, and Schiller-Duval body formations. Immunohistochemistry stains showed positivity to AE1/AE3, α-1-fetoprotein, and α-1-antitrypsin and negativity to other markers. An unusual case of a YST in the urachus is presented. This is the first reported adult case based on the authors' bibliographic search.

Yolk-shell structured Sb@C anodes for high energy Na-ion batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Junhua; Yan, Pengfei; Luo, Langli

Despite great advances in sodium-ion battery developments, the search for high energy and stable anode materials remains a challenge. Alloy or conversion-typed anode materials are attractive candidates of high specific capacity and low voltage potential, yet their applications are hampered by the large volume expansion and hence poor electrochemical reversibility and fast capacity fade. Here, we use antimony (Sb) as an example to demonstrate the use of yolk-shell structured anodes for high energy Na-ion batteries. The Sb@C yolk-shell structure prepared by controlled reduction and selective removal of Sb2O3 from carbon coated Sb2O3 nanoparticles can accommodate the Sb swelling upon sodiationmore » and improve the structural/electrical integrity against pulverization. It delivers a high specific capacity of ~554 mAh•g-1, good rate capability (315 mhA•g-1 at 10C rate) and long cyclability (92% capacity retention over 200 cycles). Full-cells of O3-Na0.9[Cu0.22Fe0.30Mn0.48]O2 cathodes and Sb@C-hard carbon composite anodes demonstrate a high specific energy of ~130 Wh•kg-1 (based on the total mass of cathode and anode) in the voltage range of 2.0-4.0 V, ~1.5 times energy of full-cells with similar design using hard carbon anodes.« less

Full-length amyloid precursor protein regulates lipoprotein metabolism and amyloid-β clearance in human astrocytes.

PubMed

Fong, Lauren K; Yang, Max M; Dos Santos Chaves, Rodrigo; Reyna, Sol M; Langness, Vanessa F; Woodruff, Grace; Roberts, Elizabeth A; Young, Jessica E; Goldstein, Lawrence S B

2018-06-01

Mounting evidence suggests that alterations in cholesterol homeostasis are involved in Alzheimer's disease (AD) pathogenesis. Amyloid precursor protein (APP) or multiple fragments generated by proteolytic processing of APP have previously been implicated in the regulation of cholesterol metabolism. However, the physiological function of APP in regulating lipoprotein homeostasis in astrocytes, which are responsible for de novo cholesterol biosynthesis and regulation in the brain, remains unclear. To address this, here we used CRISPR/Cas9 genome editing to generate isogenic APP-knockout (KO) human induced pluripotent stem cells (hiPSCs) and differentiated them into human astrocytes. We found that APP-KO astrocytes have reduced cholesterol and elevated levels of sterol regulatory element-binding protein (SREBP) target gene transcripts and proteins, which were both downstream consequences of reduced lipoprotein endocytosis. To elucidate which APP fragments regulate cholesterol homeostasis and examine whether familial AD mutations in APP affect lipoprotein metabolism, we analyzed an isogenic allelic series harboring the APP Swedish and APP V717F variants. Only astrocytes homozygous for the APP Swedish (APP Swe/Swe ) mutation, which had reduced full-length APP (FL APP) due to increased β-secretase cleavage, recapitulated the APP-KO phenotypes. Astrocytic internalization of amyloid-β (Aβ), another ligand for low-density lipoprotein (LDL) receptors, was also impaired in APP-KO and APP Swe/Swe astrocytes. Finally, impairing cleavage of FL APP through β-secretase inhibition in APP Swe/Swe astrocytes reversed the LDL and Aβ endocytosis defects. In conclusion, FL APP is involved in the endocytosis of LDL receptor ligands and required for proper cholesterol homeostasis and Aβ clearance in human astrocytes. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

ULTRASTRUCTURAL OBSERVATIONS OF VITELLOGENESIS IN THE SPIDER CRAB, LIBINIA EMARGINATA L

PubMed Central

Hinsch, Gertrude W.; Cone, M. Virginia

1969-01-01

Ovaries from the spider crab, Libinia emarginata L. were studied to learn more of vitellogenesis in crustaceans. Oogonia and previtellogenic oocytes were found in the core of the ovaries. Vitellogenic oocytes are located more peripherally. Profiles of the endoplasmic reticulum are abundant in the vitellogenic oocytes. The granular and agranular reticulum as well as the Golgi complex are active in yolk synthesis. As vitellogenesis proceeds, yolk precursors are incorporated into the egg by micropinocytosis at the egg surface. Thus, in Libinia, yolk materials appear to be derived from both intra- and extraoocytic sources. PMID:5812467

Successful treatment of mixed yolk sac tumor and mature teratoma in the spinal cord: case report.

PubMed

Mukasa, Akitake; Yanagisawa, Shunsuke; Saito, Kuniaki; Tanaka, Shota; Takai, Keisuke; Shibahara, Junji; Ikegami, Masachika; Nakao, Yusuke; Takeshita, Katsushi; Matsutani, Masao; Saito, Nobuhito

2017-03-01

Primary spinal germ cell tumors are rare, and spinal nongerminomatous germ cell tumors represent an even rarer subset for which no standard therapy has been established. The authors report the case of a 24-year-old woman with multifocal primary spinal germ cell tumors scattered from T-12 to L-5 that consisted of yolk sac tumor and mature teratoma. After diagnostic partial resection, the patient was treated with 30 Gy of craniospinal irradiation and 30 Gy of local spinal irradiation, followed by 8 courses of chemotherapy based on ifosfamide, cisplatin, and etoposide (ICE). Salvage surgery was also performed for residual mature teratoma components after the third course of ICE chemotherapy. Chemotherapy was continued after the operation, but ifosfamide was entirely eliminated from the ICE regimen because severe myelosuppression was observed after previous courses. The patient remains recurrence free as of more than 5 years after the completion of chemotherapy. This case suggests that this treatment strategy is an effective option for primary spinal yolk sac tumor.

Cryopreservation of collared peccaries (Tayassu tajacu) semen using a powdered coconut water (ACP-116c) based extender plus various concentrations of egg yolk and glycerol.

PubMed

Silva, M A; Peixoto, G C X; Lima, G L; Bezerra, J A B; Campos, L B; Paiva, A L C; Paula, V V; Silva, A R

2012-08-01

The objective was to determine the effectiveness of a powdered coconut water-based extender (ACP-116c), plus various concentrations of egg-yolk and glycerol, as an alternative for cryopreservation of collared peccary semen. Twelve ejaculates were obtained from captive adult males by electroejaculation, and evaluated for sperm motility, kinetic rating, viability, morphology, and functional membrane integrity. The ejaculates were apportioned into aliquots that were diluted in Tris plus 10% egg yolk and 3% glycerol, or in ACP-116c plus 10 or 20% egg yolk and 1.5 or 3% glycerol. Samples were frozen in liquid nitrogen and, after 1 mo, thawed at 37 °C for 1 min. After thawing, samples were evaluated as reported for fresh semen, and also for sperm membrane integrity (fluorescent probes) and kinematic parameters (computerized analysis). Results were presented as means ± SEM. Freezing and thawing decreased sperm characteristics relative to fresh semen. Overall, ACP-116c plus 20% egg yolk and 3% glycerol provided better (P < 0.05) sperm motility and kinetic rating (48 ± 6.1% and 2.8 ± 0.2, respectively) after thawing than Tris extender (30.4 ± 5.7% and 2.4 ± 0.2). However, there were no differences (P > 0.05) among treatments with regard to the other sperm characteristics. Based on computerized motion analysis, total (26.5 ± 5.9%) and progressive (8.1 ± 2.2%) motility were best preserved (P < 0.05) with the above-mentioned treatment. In conclusion, a coconut water-based extender, ACP-116c, plus 20% egg yolk and 3% glycerol, was effective for cryopreservation of semen from collared peccaries. Copyright © 2012 Elsevier Inc. All rights reserved.

Response surface optimization of pH and ionic strength for emulsion characteristics of egg yolk.

PubMed

Kurt, S; Zorba, O

2009-11-01

Effects of pH (3.5, 4.5, 6.0, 7.5, and 8.5) and ionic strength (0.05, 0.15, 0.30, 0.45, and 0.55 M NaCl) on emulsion capacity, emulsion stability (ES), apparent yield stress of emulsion (AYS), and emulsion density (ED) of egg yolk were studied by using a model system. Ionic strength and pH had significant (P < 0.01) effects on the emulsion characteristics of egg yolk. Their interaction effects also have been found significant on ES, AYS, and ED. Predicted solutions of ES, emulsion capacity, and ED were minimum. The critical point of ES was determined to be at pH 6.08 and an ionic strength of 0.49 (M NaCl). Predicted solution for AYS was a maximum, which was determined to be at pH 6.04 and an ionic strength of 0.29 (M NaCl). Optimum values of pH and ionic strenght were 4.61 to 7.43 and 0.10 to 0.47, respectively.

Replacing Corn and Wheat in Layer Diets with Hulless Oats Shows Effects on Sensory Properties and Yolk Quality of Eggs.

PubMed

Winkler, Louisa R; Hasenbeck, Aimee; Murphy, Kevin M; Hermes, James C

2017-01-01

US organic poultry producers are under pressure to find feed alternatives to corn and wheat. Hulless oats offer advantages such as wide geographic adaptation of the plant and high concentrations of protein and oil in the grain. They have shown considerable potential in experimental work as a feed grain for poultry, but more research is needed into their influence on the sensory and nutritional properties of eggs. In this study, hulless oats were substituted for corn or wheat at 200 g kg -1 in diets fed to Hy-Line Brown hens and eggs were sampled for sensory evaluation after 8 weeks. Discrimination tests of blended and baked egg samples found evidence of difference between eggs from oat-based diets and those from the oat-free control ( p  < 0.05 for eggs from an oat-corn diet, p  < 0.01 for eggs from an oat-wheat diet). Acceptance tests of similar samples showed that eggs from the oat-wheat diet were significantly less liked than control eggs for their texture ( p  < 0.01) and response to cooking ( p  < 0.01), while eggs from the oat-corn diet were somewhat less liked. Yolk weight was greater ( p  < 0.05) in control eggs (34.1 g) than eggs from oat-corn (31.6 g) or oat-wheat (31.2 g) diets, leading to smaller yolk proportion in the oat-fed eggs. Fatty acid profile differences across treatments were not of nutritional significance, and no evidence was found that the feeding of hulless oats improved storage properties of eggs. In this study, modifying the carbohydrate source in layer diets was shown to change textural properties of cooked eggs in a way that was perceptible to untrained consumers, probably by reducing the yolk proportion. This finding was not commercially relevant owing to small effect size, and results overall add to existing evidence that hulless oats can be fed to poultry at a moderate proportion of the diet with no negative effect on consumer acceptability of eggs. Regardless of the small effect size, however, findings

Replacing Corn and Wheat in Layer Diets with Hulless Oats Shows Effects on Sensory Properties and Yolk Quality of Eggs

PubMed Central

Winkler, Louisa R.; Hasenbeck, Aimee; Murphy, Kevin M.; Hermes, James C.

2017-01-01

US organic poultry producers are under pressure to find feed alternatives to corn and wheat. Hulless oats offer advantages such as wide geographic adaptation of the plant and high concentrations of protein and oil in the grain. They have shown considerable potential in experimental work as a feed grain for poultry, but more research is needed into their influence on the sensory and nutritional properties of eggs. In this study, hulless oats were substituted for corn or wheat at 200 g kg−1 in diets fed to Hy-Line Brown hens and eggs were sampled for sensory evaluation after 8 weeks. Discrimination tests of blended and baked egg samples found evidence of difference between eggs from oat-based diets and those from the oat-free control (p < 0.05 for eggs from an oat-corn diet, p < 0.01 for eggs from an oat-wheat diet). Acceptance tests of similar samples showed that eggs from the oat-wheat diet were significantly less liked than control eggs for their texture (p < 0.01) and response to cooking (p < 0.01), while eggs from the oat-corn diet were somewhat less liked. Yolk weight was greater (p < 0.05) in control eggs (34.1 g) than eggs from oat-corn (31.6 g) or oat-wheat (31.2 g) diets, leading to smaller yolk proportion in the oat-fed eggs. Fatty acid profile differences across treatments were not of nutritional significance, and no evidence was found that the feeding of hulless oats improved storage properties of eggs. In this study, modifying the carbohydrate source in layer diets was shown to change textural properties of cooked eggs in a way that was perceptible to untrained consumers, probably by reducing the yolk proportion. This finding was not commercially relevant owing to small effect size, and results overall add to existing evidence that hulless oats can be fed to poultry at a moderate proportion of the diet with no negative effect on consumer acceptability of eggs. Regardless of the small effect size, however, findings are

Novel yolk-shell-structured Fe3O4@γ-AlOOH nanocomposite modified with Pd nanoparticles as a recyclable catalyst with excellent catalytic activity

NASA Astrophysics Data System (ADS)

Cui, Xueliang; Zheng, Yunfeng; Tian, Meng; Dong, Zhengping

2017-09-01

A novel yolk-shell-structured material (Fe3O4@γ-AlOOH-YSMs) with hierarchical γ-AlOOH flakes as the mesoporous shell and Fe3O4 nanoparticles (NPs) in the hollow core was prepared by using Fe3O4@SiO2 NPs as the seeds as well as NaAlO2 and urea as the precursor. The prepared Fe3O4@γ-AlOOH-YSMs were used as a catalyst support for fabricating a Pd/Fe3O4@γ-AlOOH-YSMs nanocatalyst with no obvious aggregation of the Pd NPs. The Pd/Fe3O4@γ-AlOOH-YSMs nanocatalyst was utilized for the catalytic reduction of the widely used and highly toxic 4-nitrophenol, rhodamine B, methylene blue, and methyl orange; and showed excellent catalytic activity as compared with other noble-metal-based catalysts. Furthermore, the Pd/Fe3O4@γ-AlOOH-YSMs nanocatalyst also can be easily separated from the reaction mixture and reused for at least ten times without any obvious decrease in the catalytic activity, indicating its reusability and stability.

Processing of alkaline phosphatase precursor to the mature enzyme by an Escherichia coli inner membrane preparation.

PubMed Central

Chang, C N; Inouye, H; Model, P; Beckwith, J

1980-01-01

An inner membrane preparation co-translationally cleaved both the alkaline phosphatase and bacteriophage f1 coat protein precursors to the mature proteins. Post-translational outer membrane proteolysis of pre-alkaline phosphatase generated a protein smaller than the authentic monomer. Images PMID:6991486

Effects of food availability on yolk androgen deposition in the black-legged kittiwake (Rissa tridactyla), a seabird with facultative brood reduction

USGS Publications Warehouse

Benowitz-Fredericks, Z.M.; Kitaysky, Alexander S.; Welcker, Jorg; Hatch, Scott A.

2013-01-01

In birds with facultative brood reduction, survival of the junior chick is thought to be regulated primarily by food availability. In black-legged kittiwakes (Rissa tridactyla) where parents and chicks are provided with unlimited access to supplemental food during the breeding season, brood reduction still occurs and varies interannually. Survival of the junior chick is therefore affected by factors in addition to the amount of food directly available to them. Maternally deposited yolk androgens affect competitive dynamics within a brood, and may be one of the mechanisms by which mothers mediate brood reduction in response to a suite of environmental and physiological cues. The goal of this study was to determine whether food supplementation during the pre-lay period affected patterns of yolk androgen deposition in free-living kittiwakes in two years (2003 and 2004) that varied in natural food availability. Chick survival was measured concurrently in other nests where eggs were not collected. In both years, supplemental feeding increased female investment in eggs by increasing egg mass. First-laid (“A”) eggs were heavier but contained less testosterone and androstenedione than second-laid (“B”) eggs across years and treatments. Yolk testosterone was higher in 2003 (the year with higher B chick survival) across treatments. The difference in yolk testosterone levels between eggs within a clutch varied among years and treatments such that it was relatively small when B chick experienced the lowest and the highest survival probabilities, and increased with intermediate B chick survival probabilities. The magnitude of testosterone asymmetry in a clutch may allow females to optimize fitness by either predisposing a brood for reduction or facilitating survival of younger chicks.

NGFFFamide and echinotocin: structurally unrelated myoactive neuropeptides derived from neurophysin-containing precursors in sea urchins.

PubMed

Elphick, Maurice R; Rowe, Matthew L

2009-04-01

The myoactive neuropeptide NGIWYamide was originally isolated from the holothurian (sea cucumber) Apostichopus japonicus but there is evidence that NGIWYamide-like peptides also occur in other echinoderms. Here we report the discovery of a gene in the sea urchin Strongylocentrotus purpuratus that encodes two copies of an NGIWYamide-like peptide: Asn-Gly-Phe-Phe-Phe-(NH(2)) or NGFFFamide. Interestingly, the C-terminal region of the NGFFFamide precursor shares sequence similarity with neurophysins, carrier proteins hitherto uniquely associated with precursors of vasopressin/oxytocin-like neuropeptides. Thus, the NGFFFamide precursor is the first neurophysin-containing neuropeptide precursor to be discovered that does not contain a vasopressin/oxytocin-like peptide. However, it remains to be determined whether neurophysin acts as a carrier protein for NGFFFamide. The S. purpuratus genome also contains a gene encoding a precursor comprising a neurophysin polypeptide and 'echinotocin' (CFISNCPKGamide) - the first vasopressin/oxytocin-like peptide to be identified in an echinoderm. Therefore, in S. purpuratus there are two genes encoding precursors that have a neurophysin domain but which encode neuropeptides that are structurally unrelated. Furthermore, both NGFFFamide and echinotocin cause contraction of tube foot and oesophagus preparations from the sea urchin Echinus esculentus, consistent with the myoactivity of NGIWYamide in sea cucumbers and the myoactivity of vasopressin/oxytocin-like peptides in other animal phyla. Presumably the NGFFFamide precursor acquired its neurophysin domain following partial or complete duplication of a gene encoding a vasopressin/oxytocin-like peptide, but it remains to be determined when in evolutionary history this occurred.

RNAi Mediated curcin precursor gene silencing in Jatropha (Jatropha curcas L.).

PubMed

Patade, Vikas Yadav; Khatri, Deepti; Kumar, Kamal; Grover, Atul; Kumari, Maya; Gupta, Sanjay Mohan; Kumar, Devender; Nasim, Mohammed

2014-07-01

Curcin, a type I ribosomal inhibiting protein-RIP, encoded by curcin precursor gene, is a phytotoxin present in Jatropha (Jatropha curcas L.). Here, we report designing of RNAi construct for the curcin precursor gene and further its genetic transformation of Jatropha to reduce its transcript expression. Curcin precursor gene was first cloned from Jatropha strain DARL-2 and part of the gene sequence was cloned in sense and antisense orientation separated by an intron sequence in plant expression binary vector pRI101 AN. The construction of the RNAi vector was confirmed by double digestion and nucleotide sequencing. The vector was then mobilized into Agrobacterium tumefaciens strain GV 3101 and used for tissue culture independent in planta transformation protocol optimized for Jatropha. Germinating seeds were injured with a needle before infection with Agrobacterium and then transferred to sterilized sand medium. The seedlings were grown for 90 days and genomic DNA was isolated from leaves for transgenic confirmation based on real time PCR with NPT II specific dual labeled probe. Result of the transgenic confirmation analysis revealed presence of the gene silencing construct in ten out of 30 tested seedlings. Further, quantitative transcript expression analysis of the curcin precursor gene revealed reduction in the transcript abundance by more than 98% to undetectable level. The transgenic plants are being grown in containment for further studies on reduction in curcin protein content in Jatropha seeds.

Distinct amyloid precursor protein processing machineries of the olfactory system.

PubMed

Kim, Jae Yeon; Rasheed, Ameer; Yoo, Seung-Jun; Kim, So Yeun; Cho, Bongki; Son, Gowoon; Yu, Seong-Woon; Chang, Keun-A; Suh, Yoo-Hun; Moon, Cheil

2018-01-01

Processing of amyloid precursor protein (APP) occurs through sequential cleavages first by β-secretase and then by the γ-secretase complex. However, abnormal processing of APP leads to excessive production of β-amyloid (Aβ) in the central nervous system (CNS), an event which is regarded as a primary cause of Alzheimer's disease (AD). In particular, gene mutations of the γ-secretase complex-which contains presenilin 1 or 2 as the catalytic core-could trigger marked Aβ accumulation. Olfactory dysfunction usually occurs before the onset of typical AD-related symptoms (eg, memory loss or muscle retardation), suggesting that the olfactory system may be one of the most vulnerable regions to AD. To date however, little is known about why the olfactory system is affected so early by AD prior to other regions. Thus, we examined the distribution of secretases and levels of APP processing in the olfactory system under either healthy or pathological conditions. Here, we show that the olfactory system has distinct APP processing machineries. In particular, we identified higher expressions levels and activity of γ-secretase in the olfactory epithelium (OE) than other regions of the brain. Moreover, APP c-terminal fragments (CTF) are markedly detected. During AD progression, we note increased expression of presenilin2 of γ-secretases in the OE, not in the OB, and show that neurotoxic Aβ*56 accumulates more quickly in the OE. Taken together, these results suggest that the olfactory system has distinct APP processing machineries under healthy and pathological conditions. This finding may provide a crucial understanding of the unique APP-processing mechanisms in the olfactory system, and further highlights the correlation between olfactory deficits and AD symptoms. Copyright © 2017 Elsevier Inc. All rights reserved.

HMC-1 human mast cells synthesize neurotensin (NT) precursor, secrete bioactive NT-like peptide(s) and express NT receptor NTS1.

PubMed

Cochrane, David E; Carraway, Robert E; Harrington, Kimberly; Laudano, Melissa; Rawlings, Stephen; Feldberg, Ross S

2011-12-01

To determine if mast cells synthesize the inflammatory peptide, neurotensin (NT), secrete immunoreactive and bioactive NT, and express the NT receptor NTS1. HMC-1 cells, pleural mast cells from Sprague-Dawley rats, LAD2 mast cells, and human cord blood mast cells were used. HMC-1 cells were stimulated with NT, C48/80, mastoparan, or PGE(2). For changes in cutaneous vascular permeability, anesthetized rats were injected intravenously with Evans Blue dye and intradermally with saline, NT, histamine, diphenhydramine, and C48/80. RT-PCR was used to identify RNA transcripts. Histamine was measured by fluorometric assay. In vivo cutaneous vascular permeability assays, radio-immunoassays for NT, Western blotting for the NT precursor protein and NTS1 protein from HMC-1 cells and tissues from rats were used. Immunohistochemistry was used to identify NT precursor-like proteins in HMC-1 mast cells. HMC-1 cells express mRNAs for NT precursor, PC5A processing enzyme and NTS1 receptor. Human cord blood mast cells and LAD2 mast cells express mRNA transcripts for NT precursor and NTS1. Western blotting showed NT precursor and NTS1 receptor in HMC1. Rat tissues with high numbers of mast cells contained NT precursor proteins. NT-like peptides from HMC-1 displayed NT-like bioactivity. HMC-1 mast cells synthesize and secrete immunoreactive and bioactive NT-like peptide(s) and express the NT receptor, suggesting that NT from mast cells might serve autocrine and paracrine roles.

Fibrinogen gamma-A chain precursor in CSF: a candidate biomarker for Alzheimer's disease

PubMed Central

Lee, Joung Wook; Namkoong, Hong; Kim, Hyun Kee; Kim, Sanghee; Hwang, Dong Whi; Na, Hae Ri; Ha, Seon-Ah; Kim, Jae-Ryong; Kim, Jin Woo

2007-01-01

Background Cerebrospinal fluid (CSF) may be valuable for exploring protein markers for the diagnosis of Alzheimer's disease (AD). The prospect of early detection and treatment, to slow progression, holds hope for aging populations with increased average lifespan. The aim of the present study was to investigate candidate CSF biological markers in patients with mild cognitive impairment (MCI) and AD and compare them with age-matched normal control subjects. Methods We applied proteomics approaches to analyze CSF samples derived from 27 patients with AD, 3 subjects with MCI and 30 controls. The AD group was subdivided into three groups by clinical severity according to clinical dementia rating (CDR), a well known clinical scale for dementia. Results We demonstrated an elevated level of fibrinogen gamma-A chain precursor protein in CSF from patients with mild cognitive impairment and AD compared to the age-matched normal subjects. Moreover, its expression was more prominent in the AD group than in the MCI and correlated with disease severity and progression. In contrast, fibrinogen gamma-A chain precursor protein was detected very low in the age-matched normal group. Conclusion These findings suggest that the CSF level of fibrinogen gamma-A chain precursor may be a candidate biomarker for AD. PMID:17565664

Acute γ-secretase Inhibition of Nonhuman Primate CNS Shifts Amyloid Precursor Protein (APP) Metabolism from Amyloid-β Production to Alternative APP Fragments without Amyloid-β Rebound

PubMed Central

Cook, Jacquelynn J.; Wildsmith, Kristin R.; Gilberto, David B.; Holahan, Marie A.; Kinney, Gene G.; Mathers, Parker D.; Michener, Maria S.; Price, Eric A.; Shearman, Mark S.; Simon, Adam J.; Wang, Jennifer X.; Wu, Guoxin; Yarasheski, Kevin E.; Bateman, Randall J.

2010-01-01

The accumulation of amyloid beta (Aβ) in Alzheimer’s disease is caused by an imbalance of production and clearance, which leads to increased soluble Aβ species and extracellular plaque formation in the brain. Multiple Aβ-lowering therapies are currently in development: an important goal is to characterize the molecular mechanisms of action and effects on physiological processing of Aβ, as well as other amyloid precursor protein (APP) metabolites, in models which approximate human Aβ physiology. To this end, we report the translation of the human in vivo stable-isotope-labeling kinetics (SILK) method to a rhesus monkey cisterna magna ported (CMP) nonhuman primate model, and use the model to test the mechanisms of action of a γ-secretase inhibitor (GSI). A major concern of inhibiting the enzymes which produce Aβ (β- and γ-secretase) is that precursors of Aβ may accumulate and cause a rapid increase in Aβ production when enzyme inhibition discontinues. In this study, the GSI MK-0752 was administered to conscious CMP rhesus monkeys in conjunction with in vivo stable isotope labeling, and dose-dependently reduced newly generated CNS Aβ. In contrast to systemic Aβ metabolism, CNS Aβ production was not increased after the GSI was cleared. These results indicate that most of the CNS APP was metabolized to products other than Aβ, including C-terminal truncated forms of Aβ: 1–14, 1–15 and 1–16; this demonstrates an alternative degradation pathway for CNS amyloid precursor protein during γ-secretase inhibition. PMID:20463236

Passive immunization with hyperimmune egg yolk IgY as prophylaxis and therapy for poultry diseases---A review

USDA-ARS?s Scientific Manuscript database

Passive immunization with pathogen-specific egg yolk antibodies (IgY) is emerging as a potential alternative to antibiotics for the treatment and prevention of various human and animal diseases. Laying hens are an excellent source of high-quality polyclonal antibodies, which can be collected noninv...

Investigation of copper(II) binding to the protein precursor of Non-Amyloid-Beta Component of Alzheimer Disease Amyloid Plaque

NASA Astrophysics Data System (ADS)

Rose, Francis; Hodak, Miroslav; Bernholc, Jerry

2007-03-01

The Non-Amyloid-Beta Component Precursor (NACP) is a natively unfolded synaptic protein that is implicated in Alzheimers and Parkinsons diseases. Its aggregation into fibrillar structures is accelerated by the binding of copper(II). Experimental studies suggest that the dominant copper binding site is located at the histidine residue in NACP. Based on this evidence we assembled a model fragment of the binding site and used DFT to analyze the conformational details of the most probable binding motifs. We investigated the overall conformational effects with classical MD by constraining the copper binding site to the most energetically favorable geometry obtained from the DFT calculations. These results are compared and contrasted with those of the unbound NACP.

Contribution of Kunitz protease inhibitor and transmembrane domains to amyloid precursor protein homodimerization.

PubMed

Ben Khalifa, N; Tyteca, D; Courtoy, P J; Renauld, J C; Constantinescu, S N; Octave, J N; Kienlen-Campard, P

2012-01-01

The two major isoforms of the human amyloid precursor protein (APP) are APP695 and APP751. They differ by the insertion of a Kunitz-type protease inhibitor (KPI) sequence in the extracellular domain of APP751. APP-KPI isoforms are increased in Alzheimer's disease brains, and they could be associated with disease progression. Recent studies have shown that APP processing to Aβ is regulated by homodimerization, which involves both extracellular and juxtamembrane/transmembrane (JM/TM) regions. Our aim is to understand the mechanisms controlling APP dimerization and the contribution of the ectodomain and JM/TM regions to this process. We used bimolecular fluorescence complementation approaches coupled to fluorescence-activated cell sorting analysis to measure the dimerization level of different APP isoforms and APP C-terminal fragments (C99) mutated in their JM/TM region. APP751 was found to form significantly more homodimers than APP695. Mutation of dimerization motifs in the TM domain of APP or C99 did not significantly affect fluorescence complementation. These findings indicate that the KPI domain plays a major role in APP dimerization. They set the basis for further investigation of the relation between dimerization, metabolism and function of APP. Copyright © 2012 S. Karger AG, Basel.

Conformational Stability of the NH2-Terminal Propeptide of the Precursor of Pulmonary Surfactant Protein SP-B

PubMed Central

Bañares-Hidalgo, Ángeles; Estrada, Pilar

2016-01-01

Assembly of pulmonary surfactant lipid-protein complexes depends on conformational changes coupled with proteolytic maturation of proSP-B, the precursor of pulmonary surfactant protein B (SP-B), along the surfactant biogenesis pathway in pneumocytes. Conformational destabilization of the N-terminal propeptide of proSP-B (SP-BN) triggers exposure of the mature SP-B domain for insertion into surfactant lipids. We have studied the conformational stability during GdmCl- or urea-promoted unfolding of SP-BN with trp fluorescence and circular dichroism spectroscopies. Binding of the intermediate states to bis-ANS suggests their molten globule-like character. ΔG0H2O was ~ 12.7 kJ·mol-1 either with urea or GdmCl. None of the thermal transitions of SP-BN detected by CD correspond to protein unfolding. Differential scanning calorimetry of SP-BN evidenced two endothermic peaks involved in oligomer dissociation as confirmed with 2 M urea. Ionic strength was relevant since at 150 mM NaCl, the process originating the endotherm at the highest temperature was irreversible (Tm2 = 108.5°C) with an activation energy of 703.8 kJ·mol-1. At 500 mM NaCl the process became reversible (Tm2 = 114.4°C) and data were fitted to the Non-two States model with two subpeaks. No free thiols in the propeptide could be titrated by DTNB with or without 5.7 M GdmCl, indicating disulfide bonds establishment. PMID:27380171

Impact of dietary precursor ALA versus preformed DHA on fatty acid profiles of eggs, liver and adipose tissue and expression of genes associated with hepatic lipid metabolism in laying hens.

PubMed

Neijat, M; Eck, P; House, J D

2017-04-01

Dietary omega-3 polyunsaturated fatty acids (n-3 PUFA), including alpha-linolenic acid (ALA) and preformed longer chain PUFA (LCPUFA, particularly docosahexaenoic acid, DHA) differ in their egg LCPUFA enrichment efficiency. However, mechanisms leading to these differences are unclear. To this end, omega-3 PUFA contents in different lipid classes, including triacylglycerol (TAG) and total phospholipid (PL) in yolk, liver and adipose, as well as the expression of key hepatic enzymes in lipid metabolism were evaluated in laying hens in response to changes in dietary supply. Seventy Lohmann hens (n=10/treatment) consumed either a control diet (0.03% total omega-3 PUFA), or the control with supplementation (0.20%, 0.40% and 0.60% total omega-3 PUFA) from either flaxseed oil or algal product, as sources of ALA (precursor) or DHA (preformed), respectively. The study was arranged in a completely randomized design, and data were analyzed using the Proc Mixed procedure of SAS. ALA accumulated as a function of intake (P<0.0001) in total and lipid classes of yolk, liver and adipose (TAG only) for ALA- and DHA-fed hens. Unlike flaxseed oil, preformed-DHA contributed to greater (P<0.0001) accumulation of LCPUFA in yolk total PL and TAG pool, as well as adipose TAG. This may relate to elevated (P<0.0001) expression of acyl-CoA synthetase (ACSL1). No difference in hepatic EPA level in total lipids was noted between both treatment groups; EPA liver =2.1493x-0.0064; R 2 =0.70, P<0.0001 (x=dietary omega-3 PUFA). The latter result may highlight the role of hepatic EPA in the regulation of LCPUFA metabolism in laying hens. Copyright © 2017. Published by Elsevier Ltd.

Amyloid Precursor Protein Translation Is Regulated by a 3’UTR Guanine Quadruplex

PubMed Central

Sharoni, Michal; Olson, Kalee; Sebastian, Neeraj P.; Ansaloni, Sara; Schweitzer-Stenner, Reinhard; Akins, Michael R.; Bevilacqua, Philip C.; Saunders, Aleister J.

2015-01-01

A central event in Alzheimer’s disease is the accumulation of amyloid β (Aβ) peptides generated by the proteolytic cleavage of the amyloid precursor protein (APP). APP overexpression leads to increased Aβ generation and Alzheimer’s disease in humans and altered neuronal migration and increased long term depression in mice. Conversely, reduction of APP expression results in decreased Aβ levels in mice as well as impaired learning and memory and decreased numbers of dendritic spines. Together these findings indicate that therapeutic interventions that aim to restore APP and Aβ levels must do so within an ideal range. To better understand the effects of modulating APP levels, we explored the mechanisms regulating APP expression focusing on post-transcriptional regulation. Such regulation can be mediated by RNA regulatory elements such as guanine quadruplexes (G-quadruplexes), non-canonical structured RNA motifs that affect RNA stability and translation. Via a bioinformatics approach, we identified a candidate G-quadruplex within the APP mRNA in its 3’UTR (untranslated region) at residues 3008–3027 (NM_201414.2). This sequence exhibited characteristics of a parallel G-quadruplex structure as revealed by circular dichroism spectrophotometry. Further, as with other G-quadruplexes, the formation of this structure was dependent on the presence of potassium ions. This G-quadruplex has no apparent role in regulating transcription or mRNA stability as wild type and mutant constructs exhibited equivalent mRNA levels as determined by real time PCR. Instead, we demonstrate that this G-quadruplex negatively regulates APP protein expression using dual luciferase reporter and Western blot analysis. Taken together, our studies reveal post-transcriptional regulation by a 3’UTR G-quadruplex as a novel mechanism regulating APP expression. PMID:26618502

Amyloid precursor protein regulates migration and metalloproteinase gene expression in prostate cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyazaki, Toshiaki; Ikeda, Kazuhiro; Horie-Inoue, Kuniko

Highlights: • APP knockdown reduced proliferation and migration of prostate cancer cells. • APP knockdown reduced expression of metalloproteinase and EMT-related genes. • APP overexpression promoted LNCaP cell migration. • APP overexpression increased expression of metalloproteinase and EMT-related genes. - Abstract: Amyloid precursor protein (APP) is a type I transmembrane protein, and one of its processed forms, β-amyloid, is considered to play a central role in the development of Alzheimer’s disease. We previously showed that APP is a primary androgen-responsive gene in prostate cancer and that its increased expression is correlated with poor prognosis for patients with prostate cancer. APPmore » has also been implicated in several human malignancies. Nevertheless, the mechanism underlying the pro-proliferative effects of APP on cancers is still not well-understood. In the present study, we explored a pathophysiological role for APP in prostate cancer cells using siRNA targeting APP (siAPP). The proliferation and migration of LNCaP and DU145 prostate cancer cells were significantly suppressed by siAPP. Differentially expressed genes in siAPP-treated cells compared to control siRNA-treated cells were identified by microarray analysis. Notably, several metalloproteinase genes, such as ADAM10 and ADAM17, and epithelial–mesenchymal transition (EMT)-related genes, such as VIM, and SNAI2, were downregulated in siAPP-treated cells as compared to control cells. The expression of these genes was upregulated in LNCaP cells stably expressing APP when compared with control cells. APP-overexpressing LNCaP cells exhibited enhanced migration in comparison to control cells. These results suggest that APP may contribute to the proliferation and migration of prostate cancer cells by modulating the expression of metalloproteinase and EMT-related genes.« less

Nicotinamide Riboside Is a Major NAD+ Precursor Vitamin in Cow Milk.

PubMed

Trammell, Samuel Aj; Yu, Liping; Redpath, Philip; Migaud, Marie E; Brenner, Charles

2016-05-01

Nicotinamide riboside (NR) is a recently discovered NAD(+) precursor vitamin with a unique biosynthetic pathway. Although the presence of NR in cow milk has been known for more than a decade, the concentration of NR with respect to the other NAD(+) precursors was unknown. We aimed to determine NAD(+) precursor vitamin concentration in raw samples of milk from individual cows and from commercially available cow milk. LC tandem mass spectrometry and isotope dilution technologies were used to quantify NAD(+) precursor vitamin concentration and to measure NR stability in raw and commercial milk. Nuclear magnetic resonance (NMR) spectroscopy was used to test for NR binding to substances in milk. Cow milk typically contained ∼12 μmol NAD(+) precursor vitamins/L, of which 60% was present as nicotinamide and 40% was present as NR. Nicotinic acid and other NAD(+) metabolites were below the limits of detection. Milk from samples testing positive for Staphylococcus aureus contained lower concentrations of NR (Spearman ρ = -0.58, P = 0.014), and NR was degraded by S. aureus Conventional milk contained more NR than milk sold as organic. Nonetheless, NR was stable in organic milk and exhibited an NMR spectrum consistent with association with a protein fraction in skim milk. NR is a major NAD(+) precursor vitamin in cow milk. Control of S. aureus may be important to preserve the NAD(+) precursor vitamin concentration of milk. © 2016 American Society for Nutrition.

Amyloid beta precursor protein and ubiquitin epitopes in human and experimental dystrophic axons. Ultrastructural localization.

PubMed Central

Bacci, B.; Cochran, E.; Nunzi, M. G.; Izeki, E.; Mizutani, T.; Patton, A.; Hite, S.; Sayre, L. M.; Autilio-Gambetti, L.; Gambetti, P.

1994-01-01

Dystrophic axons (DA) represent a major pathological feature of several neurodegenerative disorders, including infantile neuroaxonal dystrophy (INAD) and Alzheimer disease. We have previously presented evidence that amyloid beta precursor protein (BPP) and ubiquitin (Ub) are present in DA of different origin. We have now characterized the immunoreactivity of DA experimentally induced in rat by the administration of parabromophenylacetylurea (BPAU) and examined the subcellular localization of Ub and BPP in BPAU-induced DA and in DA present in subjects affected by INAD. BPAU-induced DA strongly immunoreacted with antisera to Ub and to COOH- and NH2-terminal regions of BPP. Immunoblots of DA-enriched brain regions were consistent with an increase in the amount of Ub and BPP in DA. Moreover, BPAU-induced DA immunoreacted with antibodies to PGP 9.5, a neuronal-specific Ub COOH-terminal hydrolase, and to the inducible heat shock protein 70. Antigenic characterization also indicated that the tubulovesicular membranes within DA derived largely from the smooth endoplasmic reticulum rather than from the Golgi system or the synaptic vesicles. Subcellular immunolocalization of Ub and BPP in both INAD- and BPAU-induced DA revealed that Ub and BPP colocalize in granulovesicular material in both conditions. In INAD DA intense Ub immunoreactivity was also detected in nonmembranous electron dense structures that were present only in these DA, probably because of the chronic course of INAD. Although BPP immunostaining may be related to accumulation of BPP-containing membranes in DA, Ub immunostaining is likely to result from activation of the Ub system by the neuron in the attempt to remove excessive and possibly abnormal proteins. A similar pathogenesis can be postulated for DA of Alzheimer disease. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7512790

Yolk-shell structured Sb@C anodes for high energy Na-ion batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Junhua; Yan, Pengfei; Luo, Langli

Despite great advances in sodium-ion battery developments, the search for high energy and stable anode materials remains a challenge. Alloy or conversion-typed anode materials are attractive candidates of high specific capacity and low voltage potential, yet their applications are hampered by the large volume expansion and hence poor electrochemical reversibility and fast capacity fade. Here in this paper, we use antimony (Sb) as an example to demonstrate the use of yolk-shell structured anodes for high energy Na-ion batteries. The Sb@C yolk-shell structure prepared by controlled reduction and selective removal of Sb 2O 3 from carbon coated Sb 2O 3 nanoparticlesmore » can accommodate the Sb swelling upon sodiation and improve the structural/electrical integrity against pulverization. It delivers a high specific capacity of ~ 554 mAh g -1, good rate capability (315 mhA g-1 at 10 C rate) and long cyclability (92% capacity retention over 200 cycles). Full-cells of O3-Na 0.9[Cu0.22Fe 0.30Mn 0.48]O 2 cathodes and Sb@C-hard carbon composite anodes demonstrate a high specific energy of ~ 130 Wh kg-1 (based on the total mass of cathode and anode) in the voltage range of 2.0–4.0 V, ~ 1.5 times energy of full-cells with similar design using hard carbon anodes.« less

Yolk-shell structured Sb@C anodes for high energy Na-ion batteries

DOE PAGES

Song, Junhua; Yan, Pengfei; Luo, Langli; ...

2017-09-04

Despite great advances in sodium-ion battery developments, the search for high energy and stable anode materials remains a challenge. Alloy or conversion-typed anode materials are attractive candidates of high specific capacity and low voltage potential, yet their applications are hampered by the large volume expansion and hence poor electrochemical reversibility and fast capacity fade. Here in this paper, we use antimony (Sb) as an example to demonstrate the use of yolk-shell structured anodes for high energy Na-ion batteries. The Sb@C yolk-shell structure prepared by controlled reduction and selective removal of Sb 2O 3 from carbon coated Sb 2O 3 nanoparticlesmore » can accommodate the Sb swelling upon sodiation and improve the structural/electrical integrity against pulverization. It delivers a high specific capacity of ~ 554 mAh g -1, good rate capability (315 mhA g-1 at 10 C rate) and long cyclability (92% capacity retention over 200 cycles). Full-cells of O3-Na 0.9[Cu0.22Fe 0.30Mn 0.48]O 2 cathodes and Sb@C-hard carbon composite anodes demonstrate a high specific energy of ~ 130 Wh kg-1 (based on the total mass of cathode and anode) in the voltage range of 2.0–4.0 V, ~ 1.5 times energy of full-cells with similar design using hard carbon anodes.« less

Metal-Organic-Framework-Derived Yolk-Shell-Structured Cobalt-Based Bimetallic Oxide Polyhedron with High Activity for Electrocatalytic Oxygen Evolution.

PubMed

Yu, Zhou; Bai, Yu; Liu, Yuxuan; Zhang, Shimin; Chen, Dandan; Zhang, Naiqing; Sun, Kening

2017-09-20

The development of inexpensive, efficient, and environmentally friendly catalysts for oxygen evolution reaction (OER) is of great significant for green energy utilization. Herein, binary metal oxides (M x Co 3-x O 4 , M = Zn, Ni, and Cu) with yolk-shell polyhedron (YSP) structure were fabricated by facile pyrolysis of bimetallic zeolitic imidazolate frameworks (MCo-ZIFs). Benefiting from the synergistic effects of metal ions and the unique yolk-shell structure, M x Co 3-x O 4 YSP displays good OER catalytic activity in alkaline media. Impressively, Zn x Co 3-x O 4 YSP shows a comparable overpotential of 337 mV at 10 mA cm -2 to commercial RuO 2 and exhibits superior long-term durability. The high activity and good stability reveals its promising application.

Planar Cell Polarity Breaks the Symmetry of PAR Protein Distribution prior to Mitosis in Drosophila Sensory Organ Precursor Cells.

PubMed

Besson, Charlotte; Bernard, Fred; Corson, Francis; Rouault, Hervé; Reynaud, Elodie; Keder, Alyona; Mazouni, Khalil; Schweisguth, François

2015-04-20

During development, cell-fate diversity can result from the unequal segregation of fate determinants at mitosis. Polarization of the mother cell is essential for asymmetric cell division (ACD). It often involves the formation of a cortical domain containing the PAR complex proteins Par3, Par6, and atypical protein kinase C (aPKC). In the fly notum, sensory organ precursor cells (SOPs) divide asymmetrically within the plane of the epithelium and along the body axis to generate two distinct cells. Fate asymmetry depends on the asymmetric localization of the PAR complex. In the absence of planar cell polarity (PCP), SOPs divide with a random planar orientation but still asymmetrically, showing that PCP is dispensable for PAR asymmetry at mitosis. To study when and how the PAR complex localizes asymmetrically, we have used a quantitative imaging approach to measure the planar polarization of the proteins Bazooka (Baz, fly Par3), Par6, and aPKC in living pupae. By using imaging of functional GFP-tagged proteins with image processing and computational modeling, we find that Baz, Par6, and aPKC become planar polarized prior to mitosis in a manner independent of the AuroraA kinase and that PCP is required for the planar polarization of Baz, Par6, and aPKC during interphase. This indicates that a "mitosis rescue" mechanism establishes asymmetry at mitosis in PCP mutants. This study therefore identifies PCP as the initial symmetry-breaking signal for the planar polarization of PAR proteins in asymmetrically dividing SOPs. Copyright © 2015 Elsevier Ltd. All rights reserved.

An Intracellular Threonine of Amyloid-β Precursor Protein Mediates Synaptic Plasticity Deficits and Memory Loss

PubMed Central

Lombino, Franco; Biundo, Fabrizio; Tamayev, Robert; Arancio, Ottavio; D’Adamio, Luciano

2013-01-01

Mutations in Amyloid-ß Precursor Protein (APP) and BRI2/ITM2b genes cause Familial Alzheimer and Danish Dementias (FAD/FDD), respectively. APP processing by BACE1, which is inhibited by BRI2, yields sAPPß and ß-CTF. ß-CTF is cleaved by gamma-secretase to produce Aß. A knock-in mouse model of FDD, called FDDKI, shows deficits in memory and synaptic plasticity, which can be attributed to sAPPß/ß-CTF but not Aß. We have investigated further the pathogenic function of ß-CTF focusing on Thr668 of ß-CTF because phosphorylation of Thr668 is increased in AD cases. We created a knock-in mouse bearing a Thr668Ala mutation (APPTA mice) that prevents phosphorylation at this site. This mutation prevents the development of memory and synaptic plasticity deficits in FDDKI mice. These data are consistent with a role for the carboxyl-terminal APP domain in the pathogenesis of dementia and suggest that averting the noxious role of Thr668 is a viable therapeutic strategy for human dementias. PMID:23451158

Synthesis of double-shelled sea urchin-like yolk-shell Fe3O4/TiO2/Au microspheres and their catalytic applications

NASA Astrophysics Data System (ADS)

Li, Jie; Tan, Li; Wang, Ge; Yang, Mu

2015-03-01

Double-shelled sea urchin-like yolk-shell Fe3O4/TiO2/Au microspheres were successfully synthesized through loading Au nanoparticles on the Fe3O4/TiO2 support by a in situ reduction of HAuCl4 with NaBH4 aqueous solution. These microspheres possess tunable cavity size, adjustable shell layers, high structural stability and large specific surface area. The Au nanoparticles of approximately 5 nm in diameter were loaded both on the TiO2 nanofibers and inside the cavities of sea urchin-like yolk-shell Fe3O4/TiO2 microspheres. The sea urchin-like structure composed of TiO2 nanofibers ensure the good distribution of the Au nanoparticles, while the novel double-shelled yolk-shell structure guarantees the high stability of the Au nanoparticles. Furthermore, the Fe3O4 magnetic core facilitates the convenient recovery of the catalyst by applying an external magnetic field. The Fe3O4/TiO2/Au microspheres display excellent activities and recycling properties in the catalytic reduction of 4-nitrophenol (4-NP): the rate constant is 1.84 min-1 and turnover frequency is 5457 h-1.

Alterations in the Balance of Amyloid-β Protein Precursor Species in the Cerebrospinal Fluid of Alzheimer's Disease Patients.

PubMed

Lopez-Font, Inmaculada; Boix, Claudia P; Zetterberg, Henrik; Blennow, Kaj; Sáez-Valero, Javier

2017-01-01

We recently demonstrated that soluble forms of the amyloid-β protein precursor (sAβPP) assemble into multimeric complexes in cerebrospinal fluid (CSF), which contributes to the underestimation of specific sAβPP species when assessed by ELISA. To circumvent this issue, we analyzed by SDS-PAGE large fragments of sAβPP and their variants in the CSF from Alzheimer's disease (AD; n = 20) and control (n = 20) subjects, probing with specific antibodies against particular domains. Similar levels of sAβPPα and sAβPPβ protein were found in CSF samples from AD and controls, yet there appeared to be a shift in the balance of the soluble full-length AβPP (sAβPPf) species in AD samples, with a decrease in the proportion of the lower (∼100 kDa) band relative to the upper (∼120 kDa) band. Similar differences were observed in the contribution of the major KPI-immunoreactive AβPP species. CSF samples also displayed differences in the correlations of AβPP species with classical AD biomarkers, particularly with respect to the Aβ42 peptide. The differences reveal alterations that probably reflect pathophysiological changes in the brain.

Novel Roles of Amyloid-Beta Protein Precursor Metabolites in Fragile X Syndrome and Autism

PubMed Central

Westmark, Cara J.; Sokol, Deborah K.; Maloney, Bryan; Lahiri, Debomoy K.

2017-01-01

Fragile X syndrome (FXS) is the most common form of inherited intellectual disability and is associated with up to 5% of autism cases. Several promising drugs are in preclinical testing for FXS; however, bench-to-bedside plans for the clinic are severely limited due to lack of validated biomarkers and outcome measures. Published work from our laboratories has demonstrated altered levels of amyloid-beta (Aβ) protein precursor (APP) and its metabolites in FXS and idiopathic autism. Westmark and colleagues have focused on β-secretase (amyloidogenic) processing and the accumulation of Aβ peptides in adult FXS models while Lahiri and Sokol have studied α-secretase (nonamyloidogenic or anabolic) processing and altered levels of sAPPα and Aβ in pediatric autism and FXS. Thus, our groups have hypothesized a pivotal role for these Alzheimer’s disease (AD)-related proteins in the neurodevelopmental disorders of FXS and autism. In this review, we discuss the contribution of APP metabolites to FXS and autism pathogenesis as well as the potential use of these metabolites as blood-based biomarkers and therapeutic targets. Our future focus is to identify key underlying mechanisms through which APP metabolites contribute to FXS and autism condition-to-disease pathology. Positive outcomes will support utilizing APP metabolites as blood-based biomarkers in clinical trials as well as testing drugs that modulate APP processing as potential disease therapeutics. Our studies to understand the role of APP metabolites in developmental conditions such as FXS and autism are a quantum leap for the neuroscience field, which has traditionally restricted any role of APP to AD and aging. PMID:27573877

Problem-Solving Test: Vitellogenin and Vitellogenin-Receptor Recognition: An Example of Protein Interaction

ERIC Educational Resources Information Center

Hernandez-Cortes, Patricia

2012-01-01

Vitellogenin (Vtg) is a lipid transfer protein that carries yolk to the ovary. The vitellogenin receptor (VtgR) mediates the uptake of Vtg into the oocyte of oviparous animals; its structure includes eight ligand-binding repeats (LBR). The binding site of VtgR and Vtg and the location of the interaction within the molecules are at these LBR.…

Crystallization and preliminary X-ray diffraction study of the protealysin precursor belonging to the peptidase family M4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gromova, T. Yu., E-mail: duk@img.ras.ru; Demidyuk, I. V.; Kostrov, S. V.

2008-09-15

A protealysin precursor (the enzyme of the peptidase family M4) was crystallized for the first time. The crystal-growth conditions were found, and single crystals of the protein with dimensions of 0.3-0.5 mm were grown. The preliminary X-ray diffraction study of the enzyme was performed. The protealysin precursor was shown to crystallize in two crystal modifications suitable for the X-ray diffraction study of the three-dimensional structure of the protein molecule at atomic resolution.

Super-hydrophobic yolk-shell nanostructure with enhanced catalytic performance in the reduction of hydrophobic nitroaromatic compounds.

PubMed

Shi, Song; Wang, Min; Chen, Chen; Gao, Jin; Ma, Hong; Ma, Jiping; Xu, Jie

2013-10-25

A self-templating method to fabricate a super-hydrophobic yolk-shell nano-reactor was reported. Metal nanoparticles were encapsulated in the porous super-hydrophobic shell. This super-hydrophobic catalyst showed excellent performance in the reduction of nitroaromatic compounds in aqueous phase and a positive correlation was found between the reaction rate and the hydrophobicity of the substrate.

Egg yolk-free Baird-Parker medium for the accelerated enumeration of foodborne Staphylococcus aureus.

PubMed Central

Lachica, R V

1984-01-01

A simplified procedure is described for the accelerated enumeration of foodborne Staphylococcus aureus. This involves the replacement of egg yolk in the Baird-Parker medium with Tween 80 and MgCl2. These compounds, along with pyruvate, allow the recovery of stressed cells of S. aureus on a medium which contains potassium tellurite, LiCl, and glycine as selective agents. Black colonies are identified as S. aureus by the simplified thermonuclease test. PMID:6542337

Protein secretion and surface display in Gram-positive bacteria

PubMed Central

Schneewind, Olaf; Missiakas, Dominique M.

2012-01-01

The cell wall peptidoglycan of Gram-positive bacteria functions as a surface organelle for the transport and assembly of proteins that interact with the environment, in particular, the tissues of an infected host. Signal peptide-bearing precursor proteins are secreted across the plasma membrane of Gram-positive bacteria. Some precursors carry C-terminal sorting signals with unique sequence motifs that are cleaved by sortase enzymes and linked to the cell wall peptidoglycan of vegetative forms or spores. The sorting signals of pilin precursors are cleaved by pilus-specific sortases, which generate covalent bonds between proteins leading to the assembly of fimbrial structures. Other precursors harbour surface (S)-layer homology domains (SLH), which fold into a three-pronged spindle structure and bind secondary cell wall polysaccharides, thereby associating with the surface of specific Gram-positive microbes. Type VII secretion is a non-canonical secretion pathway for WXG100 family proteins in mycobacteria. Gram-positive bacteria also secrete WXG100 proteins and carry unique genes that either contribute to discrete steps in secretion or represent distinctive substrates for protein transport reactions. PMID:22411983

Rapid endocytosis of the low density lipoprotein receptor-related protein modulates cell surface distribution and processing of the beta-amyloid precursor protein.

PubMed

Cam, Judy A; Zerbinatti, Celina V; Li, Yonghe; Bu, Guojun

2005-04-15

The low density lipoprotein receptor-related protein (LRP) is a approximately 600-kDa multifunctional endocytic receptor that is highly expressed in the brain. LRP and its ligands apolipoprotein E, alpha2-macroglobulin, and beta-amyloid precursor protein (APP), are genetically linked to Alzheimer disease and are found in characteristic plaque deposits in brains of patients with Alzheimer disease. To identify which extracellular domains of LRP interact with APP, we used minireceptors of each of the individual LRP ligand binding domains and assessed their ability to bind and degrade a soluble APP fragment. LRP minireceptors containing ligand binding domains II and IV, but not I or III, interacted with APP. To test whether APP trafficking is directly related to the rapid endocytosis of LRP, we generated stable Chinese hamster ovary cell lines expressing either a wild-type LRP minireceptor or its endocytosis mutants. Chinese hamster ovary cells stably expressing wild-type LRP minireceptor had less cell surface APP than pcDNA3 vector-transfected cells, whereas those stably expressing endocytosis-defective LRP minireceptors accumulated APP at the cell surface. We also found that the steady-state levels of the amyloid beta-peptides (Abeta) is dictated by the relative expression levels of APP and LRP, probably reflecting the dual roles of LRP in both Abeta production and clearance. Together, these data establish a relationship between LRP rapid endocytosis and APP trafficking and proteolytic processing to generate Abeta.

Substance P activates ADAM9 mRNA expression and induces α-secretase-mediated amyloid precursor protein cleavage.

PubMed

Marolda, R; Ciotti, M T; Matrone, C; Possenti, R; Calissano, P; Cavallaro, S; Severini, C

2012-04-01

Altered levels of Substance P (SP), a neuropeptide endowed with neuroprotective and anti-apoptotic properties, were found in brain areas and spinal fluid of Alzheimer's disease (AD) patients. One of the hallmarks of AD is the abnormal extracellular deposition of neurotoxic beta amyloid (Aβ) peptides, derived from the proteolytic processing of amyloid precursor protein (APP). In the present study, we confirmed, the neurotrophic action of SP in cultured rat cerebellar granule cells (CGCs) and investigated its effects on APP metabolism. Incubation with low (5 mM) potassium induced apoptotic cell death of CGCs and amyloidogenic processing of APP, whereas treatment with SP (200 nM) reverted these effects via NK1 receptors. The non-amyloidogenic effect of SP consisted of reduction of Aβ(1-42), increase of sAPPα and enhanced α-secretase activity, without a significant change in steady-state levels of cellular APP. The intracellular mechanisms whereby SP alters APP metabolism were further investigated by measuring mRNA and/or steady-state protein levels of key enzymes involved with α-, β- and γ-secretase activity. Among them, Adam9, both at the mRNA and protein level, was the only enzyme to be significantly down-regulated following the induction of apoptosis (K5) and up-regulated after SP treatment. In addition to its neuroprotective properties, this study shows that SP is able to stimulate non-amyloidogenic APP processing, thereby reducing the possibility of generation of toxic Aβ peptides in brain. Copyright © 2011 Elsevier Ltd. All rights reserved.

Multisite tyrosine phosphorylation of the N-terminus of Mint1/X11α by Src kinase regulates the trafficking of amyloid precursor protein.

PubMed

Dunning, Christopher J R; Black, Hannah L; Andrews, Katie L; Davenport, Elizabeth C; Conboy, Michael; Chawla, Sangeeta; Dowle, Adam A; Ashford, David; Thomas, Jerry R; Evans, Gareth J O

2016-05-01

Mint/X11 is one of the four neuronal trafficking adaptors that interact with amyloid precursor protein (APP) and are linked with its cleavage to generate β-amyloid peptide, a key player in the pathology of Alzheimer's disease. How APP switches between adaptors at different stages of the secretory pathway is poorly understood. Here, we show that tyrosine phosphorylation of Mint1 regulates the destination of APP. A canonical SH2-binding motif ((202) YEEI) was identified in the N-terminus of Mint1 that is phosphorylated on tyrosine by C-Src and recruits the active kinase for sequential phosphorylation of further tyrosines (Y191 and Y187). A single Y202F mutation in the Mint1 N-terminus inhibits C-Src binding and tyrosine phosphorylation. Previous studies observed that co-expression of wild-type Mint1 and APP causes accumulation of APP in the trans-Golgi. Unphosphorylatable Mint1 (Y202F) or pharmacological inhibition of Src reduced the accumulation of APP in the trans-Golgi of heterologous cells. A similar result was observed in cultured rat hippocampal neurons where Mint1(Y202F) permitted the trafficking of APP to more distal neurites than the wild-type protein. These data underline the importance of the tyrosine phosphorylation of Mint1 as a critical switch for determining the destination of APP. The regulation of amyloid precursor protein (APP) trafficking is poorly understood. We have discovered that the APP adapter, Mint1, is phosphorylated by C-Src kinase. Mint1 causes APP accumulation in the trans-Golgi network, whereas inhibition of Src or mutation of Mint1-Y202 permits APP recycling. The phosphorylation status of Mint1 could impact on the pathological trafficking of APP in Alzheimer's disease. © 2016 The Authors. Journal of Neurochemistry published by John Wiley & Sons Ltd on behalf of International Society for Neurochemistry.

Sperm characteristics following freezing in extenders supplemented with whole egg yolk and different concentrations of low-density lipoproteins in the collared peccary (Pecari tajacu).

PubMed

Souza, Ana Liza Paz; Lima, Gabriela Liberalino; Peixoto, Gislayne Christianne Xavier; de Souza Castelo, Thibério; Oliveira, Maria Glaucia Carlos; de Paula, Valéria Veras; Silva, Alexandre Rodrigues

2015-12-01

The aim of the current study was to compare sperm quality characteristics of the collared peccary (Pecari tajacu) following freezing in extenders supplemented with whole egg yolk and different concentrations of low-density lipoproteins (LDL). Semen from 11 adult males was obtained by electroejaculation and evaluated for sperm motility, vigor, morphology as well as membrane integrity analyzed by the hypo-osmotic swelling (HOS) test and a fluorescent staining. Moreover, the semen was diluted in a Tris-based extender containing 20% egg yolk (control group) or 5, 10 or 20% LDL (treatment groups). The semen samples were frozen in liquid nitrogen and thawed in a water bath for 60s at 37°C. The treatments did not affect (p>0.05) sperm vigor, morphology or membrane integrity analyzed by the HOS test. However, post-thaw sperm motility was significantly higher (p<0.05) in the extender supplemented with 20% LDL (36.4 ± 5.3%) compared with the egg yolk extender and extender supplemented with 10% LDL. Furthermore, the percentage of membrane-intact frozen-thawed spermatozoa analyzed by the fluorescent staining was significantly higher (p<0.05) in the extender supplemented with 20% LDL (27.4 ± 6.5%) than in the other groups. In conclusion, 20% LDL can be used to substitute the whole egg yolk as a cryoprotective additive for freezing semen of the collared peccary. Copyright © 2015 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Comparison of the effects of dietary supplementation of flavonoids on laying hen performance, egg quality and egg nutrient profile.

PubMed

Iskender, H; Yenice, G; Dokumacioglu, E; Kaynar, O; Hayirli, A; Kaya, A

2017-10-01

1. The aim of this experiment was to compare the effects of dietary supplementation of hesperidin, naringin and quercetin on laying hen performance, egg quality and egg yolk lipid and protein profiles. 2. A total of 96 Lohmann White laying hens weighing an average of 1500 g at 28 weeks of age were randomly assigned to a basal diet and the basal diet supplemented (0.5 g/kg) with either hesperidin, naringin or quercetin. Each treatment was replicated in 6 cages in an 8-week experimental period. Data were analysed using one-way analysis of variance. 3. None of the dietary flavonoids affected laying performance and eggshell quality. Hesperidin and quercetin supplementations decreased albumen and yolk indexes. 4. As compared to the control group, egg yolk cholesterol content decreased and egg yolk protein content increased in response to dietary hesperidin and quercetin supplementation. The mean egg yolk cholesterol (mg/g) and protein (g/100 g) contents were 10.08/14.28, 16.12/14.08, 14.75/15.04 and 15.15/14.85 for the control group and groups supplemented with naringin, hesperidin and quercetin, respectively. 5. Egg yolk lipid and protein profiles were variable. 6. In conclusion, dietary supplementation of hesperidin or quercetin could be used in the diets during the early laying period to reduce egg yolk cholesterol and increase egg yolk protein, which may be attractive to consumers.

Impact of membrane lipid composition on the structure and stability of the transmembrane domain of amyloid precursor protein

PubMed Central

Dominguez, Laura; Foster, Leigh; Straub, John E.; Thirumalai, D.

2016-01-01

Cleavage of the amyloid precursor protein (APP) by γ-secretase is a crucial first step in the evolution of Alzheimer’s disease. To discover the cleavage mechanism, it is urgent to predict the structures of APP monomers and dimers in varying membrane environments. We determined the structures of the C9923−55 monomer and homodimer as a function of membrane lipid composition using a multiscale simulation approach that blends atomistic and coarse-grained models. We demonstrate that the C9923−55 homodimer structures form a heterogeneous ensemble with multiple conformational states, each stabilized by characteristic interpeptide interactions. The relative probabilities of each conformational state are sensitive to the membrane environment, leading to substantial variation in homodimer peptide structure as a function of membrane lipid composition or the presence of an anionic lipid environment. In contrast, the helicity of the transmembrane domain of monomeric C991−55 is relatively insensitive to the membrane lipid composition, in agreement with experimental observations. The dimer structures of human EphA2 receptor depend on the lipid environment, which we show is linked to the location of the structural motifs in the dimer interface, thereby establishing that both sequence and membrane composition modulate the complete energy landscape of membrane-bound proteins. As a by-product of our work, we explain the discrepancy in structures predicted for C99 congener homodimers in membrane and micelle environments. Our study provides insight into the observed dependence of C99 protein cleavage by γ-secretase, critical to the formation of amyloid-β protein, on membrane thickness and lipid composition. PMID:27559086

Replacing egg yolk with soybean lecithin in the cryopreservation of stallion semen.

PubMed

Papa, Frederico Ozanam; Felício, Gabriel Barcelos; Melo-Oña, Cely Marini; Alvarenga, Marco Antonio; De Vita, Bruna; Trinque, Cássio; Puoli-Filho, José Nicolau P; Dell'Aqua, José Antonio

2011-11-01

The objective of this study was to determine whether replacing the egg yolk with soybean lecithin in the Botu-Crio® cryodiluent would maintain the fertility of cryopreserved stallion sperm. Two experiments were performed to evaluate cell freezability. In experiment 1, sperm from 15 stallions were frozen in Botu-Crio® (BC) or Botu-Crio® which contained 45g/L soybean lecithin (BCLS45) in place of the egg yolk. In experiment 2, we compared different concentrations of soybean lecithin: 0, 10.0, 12.5, 15.0, 17.5 and 20.0g/L (BC, BCLS10, BCLS12.5, BCLS17.5 and BCLS20, respectively). In experiment 1, sperm frozen in BC and BCLS45 exhibited similar (P>0.05) percentages of total motile sperm (61% and 61%, respectively); progressively motile sperm (27% and 27%, respectively) and sperm with intact plasma membranes (IMP; 53% and 57%, respectively). Similarly, sperm frozen in BC or BC containing any concentration of soybean lecithin maintained similar (P>0.05) percentages of total motile sperm (61-68%) and progressively motile sperm (27-31%). In the first fertility trial, we used cryopreserved semen from a single stallion was inseminated into mares. The semen from the sperm that were frozen in BC diluent resulted in a higher fertility rate (66%, 16/24) compared to the sperm that were frozen in BCLS45 diluent (17%, 5/29; P<0.01). Similarly, in a second fertility trial, the mares that were inseminated with the sperm that were frozen in BC diluent exhibited a higher fertility rate (66%, 16/24) compared to the mares that were inseminated with the sperm that were frozen in BCLS20 (40%, 10/25; P<0.05). Finally, in a third trial, the sperm that were frozen in BC resulted in a higher fertility rate in mares (75%, 18/24) compared to the sperm that were frozen in BCLS10 (41%, 10/24; P<0.05). Although replacing the egg yolk in the BC cryodiluent with soybean lecithin provided similar laboratory results for stallion sperm, after cryopreservation, the sperm that was frozen with soybean

Relative increase in Alzheimer's disease of soluble forms of cerebral Abeta amyloid protein precursor containing the Kunitz protease inhibitory domain.

PubMed

Moir, R D; Lynch, T; Bush, A I; Whyte, S; Henry, A; Portbury, S; Multhaup, G; Small, D H; Tanzi, R E; Beyreuther, K; Masters, C L

1998-02-27

Although a number of studies have examined amyloid precursor protein (APP) mRNA levels in Alzheimer's disease (AD), no clear consensus has emerged as to whether the levels of transcripts for isoforms containing a Kunitz protease inhibitory (KPI)-encoded region are increased or decreased in AD. Here we compare AD and control brain for the relative amounts of APP protein containing KPI to APP protein lacking this domain. APP protein was purified from the soluble subcellular fraction and Triton X-100 membrane pellet extract of one hemisphere of AD (n = 10), normal (n = 7), and neurological control (n = 5) brains. The amount of KPI-containing APP in the purified protein samples was determined using two independent assay methods. The first assay exploited the inhibitory action of KPI-containing APP on trypsin. The second assay employed reflectance analysis of Western blots. The proportion of KPI-containing forms of APP in the soluble subcellular fraction of AD brains is significantly elevated (p < 0.01) compared with controls. Species containing a KPI domain comprise 32-41 and 76-77% of purified soluble APP from control and AD brains, respectively. For purified membrane-associated APP, 72-77 and 65-82% of control and AD samples, respectively, contain a KPI domain. Since KPI-containing species of APP may be more amyloidogenic (Ho, L., Fukuchi, K., and Yonkin, S. G. (1996) J. Biol. Chem. 271, 30929-30934), our findings support an imbalance of isoforms as one possible mechanism for amyloid deposition in sporadic AD.