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PubMed1990

Use of oyster shell as calcium supplement. Part 1. Effect on the utilization of gossypol-containing cotton seed cake by the chicken.

The comparative utilization of cottonseed cake (CSC) diet supplemented with varying levels of oyster shell (0.00, 1.50, 3.00 and 4.50%) as a source of calcium, and groundnut cake (GNC) based diet were evaluated in a feeding trial using 100 day-old HYPECO broiler-chicks. The response criteria included performance, carcass traits and economics of production. The weight gains at the end of the trial were not significantly different. However, feed consumption significantly (P less than 0.5) increased with increasing dietary calcium. Feed consumption was significantly (P less than 0.05) correlated with dietary calcium levels with r = 0.96. Feed efficiency and protein efficiency ratio were significantly (P less than 0.05) better in the GNC diets than CSC based diets in spite of the oyster shell supplementation of the latter. Both nitrogen retention and apparent nitrogen digestibility were not significantly influenced. The percent dressed weight, percent eviscerated weight and the relative weights of the thigh, drumstick, chest, back, head and belly fat were not significantly influenced by the dietary treatment. Only the relative weight of the shank was significantly (P less than 0.05) influenced. The cost-benefit analysis showed that although it was chapter to formulate CSC diets, profits were identical with GNC diets when fed to the chicks. It was suggested that CSC could be a good substitute for GNC because of the ready availability of the former. Dietary calcium of up to 1.82% was beneficial in the utilization of the CSC.

Animal Feed↗

PubMed2002

Electron localization and delocalization in open-shell molecules.

Localization and delocalization indices derived in the framework of the quantum Atoms in Molecules theory have recently been used to analyze the electron-pair structure of closed-shell molecules. Here we report calculations of localization and delocalization indices for open-shell molecules at the Hartree-Fock (HF) level. Several simple doublet and triplet radical molecules are studied. In general, interatomic delocalization between bonded atoms is heavily dependent on the order and polarity of the bond. Unpaired electrons also have a significant effect on the interatomic delocalization indices. Indeed, for many radicals, the analysis of the spin components reveals that the interatomic delocalization is very different for alpha and beta spin electrons in many cases. In general, at the HF level, the results can be rationalized in terms of orbital contributions. However, the definition of localization and delocalization indices is completely general, and they could be calculated at any level of theory, provided that the one- and two-electron densities are available.

Journal Article↗

PubMed2004

Fluorescence shell: a novel view of sclereid morphology with the Confocal Laser Scanning Microscope.

Confocal Laser Scanning Microscopy (CLSM) was used to observe sclereids from stems of Avicennia germinans and from fruits of two species of pear (Pyrus calleryana "Bradford" and P. communis "Red Bartlett"). The images obtained from thick (25 to 100 microm) free-hand sections were, in certain respects, far superior to those obtained by other, more invasive and time-consuming microscopic techniques upon which previous reports of sclereid morphology were based. The cell wall surfaces, including the "internal" surfaces of the branched pit canals and cell lumens, were much accentuated with the techniques we describe, resulting in a "fluorescence shell" image, meaning the cell wall did not stain all the way through but instead only at the inner and outer wall surfaces, including the edges of ramiform pits. By controlling the time of staining with 1% aqueous Safranin O, or by changing the number of optical sections used in extended focus images, it was possible to get either a conventional view of the cell wall structure or a unique, three-dimensional view of the elaborate cell interconnections. Similar fluorescence shell images of sclereids were also obtained using a periodic-Schiff (PAS) staining system, but the stain was not as specific to sclereid cell walls as was the Safranin O stain. Particularly with the use of a narrow range band pass emission filter of 505-530 nm, the Safranin O staining may be more specific to lignin than reported in the literature.

Avicennia↗

PubMed2005

Hox code in embryos of Chinese soft-shelled turtle Pelodiscus sinensis correlates with the evolutionary innovation in the turtle.

Turtles have the most unusual body plan of the amniotes, with a dorsal shell consisting of modified ribs. Because this morphological change in the ribs can be described as an axial-level specific alteration, the evolution of the turtle carapace should depend on changes in the Hox code. To identify turtle-specific changes in developmental patterns, we cloned several Hox genes from the Chinese soft-shelled turtle, Pelodiscus sinensis, examined their expression patterns during embryogenesis, and compared them with those of chicken and mouse embryos. We detected possibly turtle-specific derived traits in Hoxc-6 expression, which is restricted to the paraxial part of the embryo; in the expression of Hoxa-5 and Hoxb-5, the transcripts of which were detected only at the cervical level; and in Hoxc-8 and Hoxa-7 expression, which is shifted anteriorly relative to that of the other two amniote groups. From the known functions of the Hox orthologs in model animals, these P. sinensis-specific changes apparently correlate with specializations in the turtle-specific body plan.

Animals↗

PubMed1988

The morphogenesis of molluscan shells: a mathematical account using biological parameters.

In attempts to account mathematically for the morphogenesis of biological structures it is important that the parameters chosen for the purpose should be "biological," that is, they should refer directly to the growth processes through which the structure is formed. Molluscan shells are formed by accretional growth at the mantle edge, and the parameters used for the mathematical description of their formation should therefore refer to events taking place there. In the best of previous attempts to solve this problem, two out of three form parameters have met with this demand, but it was not possible to eliminate beta, half the apical angle of the cone on which lie the centers of successive whorls. It is shown here that beta may be eliminated for many forms of molluscan shells, and when this is not the case beta may indeed be referred to processes taking place at the mantle edge.

Animals↗

PubMed1995

Comparison of monoclonal antibodies for immunostaining in the cytomegalovirus shell vial assay on 4,388 specimens.

The shell vial assay is a sensitive, rapid test for the detection of cytomegalovirus (CMV) in a variety of specimens. The sensitivity of this assay is dependent on a number of factors including the antibodies used for immunostaining. Monoclonal antibodies to the CMV major immediate-early antigen (p72) from Chemicon (MAB810) and Dupont (NEA-9221) were assessed side by side in duplicate vials on 4,388 specimens from a patient population consisting of > 90% organ transplant recipients. A total of 240 specimens (5.5%) were CMV positive in either one or both vials. Positivity rates were variable across different specimen types but highest (12.9%) in urine specimens. Of the positive specimens, 175 (72.9%) tested positive in both vials, 43 (17.9%) tested positive in the Chemicon-stained vial only, and 22 (9.2%) tested positive in the Dupont-stained vial only (P < 0.01, McNemar's chi-square test). This gave an overall positivity rate of 5.0% for Chemicon antibodies and 4.5% for Dupont. There was no difference in the fluorescent focus counts produced by the two antibody sets. It is concluded that use of the Chemicon antibodies provides increased sensitivity of detection of CMV in the shell vial assay above that afforded by the Dupont antibody.

Antibodies, Monoclonal↗

PubMed1975

Soft gelatin capsules II: Oxygen permeability study of capsule shells.

A method is reported for studying the effects of several factors at room temperature on the oxygen permeability of soft gelatin capsule shell films. The method involves the use of a permeability cell assembly and the spectrophotometric determïnation of oxygen with an alkaline pyrogallic acid solution. Factors investigated were relative humidity, plasticizers, equilibrium water, an insoluble additive, and film thickness. Results from the effects of film thickness and oxygen partial pressure correlated well with the permeability equation. For greatest stability of encapsulated oxygen-labile materials, it is recommended that the soft gelatin capsule shells be prepared with a low plasticizer concentration and that the finished capsules be stored at low relative humidity.

Capsules↗

PubMed2005

Hydrophilic core-shell microspheres: a suitable support for controlled attachment of proteins and biomedical diagnostics.

Functional hydrophilic microspheres (latex particles) have found various applications in life sciences and in medicine - particularly in latex diagnostic tests. This paper presents a comprehensive review of studies on latex particles with a hydrophilic interfacial layer composed of various hydrophilic polymers with reactive groups at the ends of macromolecules or at each monomeric unit along the chain. Typical examples of these hydrophilic polymers are poly(2-hydroxyethyl methyl methacrylate), poly(acrylic acid), poly(N,N-dimethylacrylamide), polysaccharides, poly(ethylene oxide) and polyglycidol. Hydrophilic microspheres with different morphologies (uniform or core-shell, see Figure) have been synthesized by emulsion and dispersion polymerizations. The chemical structure of polymers which constitute the interfacial layer of microspheres has been investigated using a variety of instrumental techniques (such as XPS, SSIMS and NMR) and analytical methods based on specific chemical reactions suitable for the determination of particular functional groups. Microspheres are exposed to contact with proteins in the majority of medical applications. This paper presents examples of studies on the attachment of these biomacromolecules to microspheres. The relation between the structure of the interfacial layer of microspheres and the ability of these particles for the covalent binding of proteins is discussed. Several examples of diagnostic tests, in which hydrophilic microspheres with adsorbed or covalently immobilized proteins were used as reagents, are presented. The paper also contains a short review of the application of magnetic hydrophilic particles for protein separation. Examples of hydrophilic latex particles used for hemoperfusion or heavy metal ion separation are presented. Hydrophilic microspheres with uniform or core-shell morphologies.

Animals↗

PubMed2003

Cloning and expression of a novel cDNA encoding shell coat protein, cp4, from the brushtail possum (Trichosurus vulpecula).

The marsupial conceptus is enclosed by several egg coats of evolutionary significance and unknown composition, of which the shell coat in mammals occurs only in marsupials and monotremes. Intact coats are vital to marsupial embryonic development. Towards a better understanding of the marsupial coat proteins, a cDNA sequence (cp4) encoding a shell coat protein was cloned from the brushtail possum. A cDNA library of a zygote stage uterus was screened using a deduced oligonucleotide sequence based on a partial amino acid sequence of the coat protein. This study has confirmed a single copy cp4 gene encoding a unique protein of 306 amino acids, although its N-terminus shares high sequence identity with the C-terminal half of the enzyme alpha-enolase. Using Northern blots, the expression of cp4 in adult tissues showed that cp4 transcript is restricted predominantly to the uterus with two stages of expression occurring in the gravid uterus at early cleavage and bilaminar stages, suggesting an important developmental role for CP4. Using RT-PCR, cp4-specific expression as represented by the 3'-end 400 bp was present in heart, liver, oviduct, and uterus. Uterine expression reflected the increase found with Northern blot except that expression was low at unilaminar and bilaminar stages.

Amino Acid Sequence↗

PubMed2001

The solvent shells of cluster ions produced by direct electric field extraction from glycerol/water mixtures.

Electric field extraction of gaseous negative ions directly from water/glycerol solutions by use of a track membrane technique was investigated. The distributions of numbers of solvent molecules in the extracted cluster ions for different compounds were obtained. It is shown that the extraction mechanism is a direct field-stimulated evaporation of cluster ions from liquid, with a subsequent loss of several solvent molecules in the vacuum. For relatively simple ions a good correspondence of results was obtained with a continuous medium model. It was found that the number of solvent molecules in a cluster shell, for more complicated ions such as amino acids, is significantly greater than that for halide ions or ions of simple organic acids. An increase in the number of solvent molecules in the case of amino acid negative ions is rationalized in terms of the existence of several charged groups, each of which gives an additional contribution to the cluster shell.

Algorithms↗

PubMed2005

Growth of semiconducting GaN hollow spheres and nanotubes with very thin shells via a controllable liquid gallium-gas interface chemical reaction.

An in situ liquid gallium-gas interface chemical reaction route has been developed to synthesize semiconducting hollow GaN nanospheres with very small shell size by carefully controlling the synthesis temperature and the ammonia reaction gas partial pressure. In this process the gallium droplet does not act as a catalyst but rather as a reactant and a template for the formation of hollow GaN structures. The diameter of the synthesized hollow GaN spheres is typically 20-25 nm and the shell thickness is 3.5-4.5 nm. The GaN nanotubes obtained at higher synthesis temperatures have a length of several hundreds of nanometers and a wall thickness of 3.5-5.0 nm. Both the hollow GaN spheres and nanotubes are polycrystalline and are composed of very fine GaN nanocrystalline particles with a diameter of 3.0-3.5 nm. The room-temperature photoluminescence (PL) spectra for the synthesized hollow GaN spheres and nanotubes, which have a narrow size distribution, display a sharp, blue-shifted band-edge emission peak at 3.52 eV (352 nm) due to quantum size effects.

Ammonia↗

PubMed2006

Conversion of a Bi nanowire array to an array of Bi-Bi2O3 core-shell nanowires and Bi2O3 nanotubes.

A template-based heat-treatment method has been developed to convert metal nanowire arrays into arrays of metal-metal oxide core-shell nanowires and single-crystalline metal oxide nanotubes. This process is demonstrated by kinetically controlling the conversion of single-crystalline Bi nanowires to Bi-Bi(2)O(3) core-shell nanowires via a multistep, slow oxidation method, and then controlling their further conversion to a single-crystalline Bi(2)O(3) nanotube array via fast oxidation. This process can conveniently be extended to fabricate a free-standing, easily oxidized metal-metal oxide nanowire and metal oxide nanotube array, which may have future applications in nanoscale optics, electronics, and magnetics.

Bismuth↗

PubMed2002

Decreased haloperidol-induced potentiation of zif268 mRNA expression in the nucleus accumbens shell and the dorsal lateral striatum of rats lacking cholecystokinin-A receptors.

Evidence suggests that endogenous cholecystokinin (CCK), a neuropeptide that modulates brain dopamine function, may contribute to the therapeutic and motor effects of antipsychotic drugs via activation of CCK-A receptors in the mesolimbic and nigrostriatal pathways, respectively. To determine if CCK modulates the effects of antipsychotic drugs through CCK-A receptors, we measured the haloperidol-induced zif268 mRNA response in the nucleus accumbens (NA) shell, NA core, and dorsal lateral striatum (DLS) in Otsuka Long Evans Tokushima Fatty (OLETF) rats that lack CCK-A receptors due to a spontaneous mutation. OLETF rats and normal Long Evans rats were treated with subcutaneous (s.c.) injections of saline or haloperidol (2 mg/kg). In situ hybridization was performed and zif268 mRNA expression was quantified. The haloperidol-induced expression of zif268 mRNA was significantly decreased in the DLS (P < 0.01) and the NA shell (P < 0.05), but not in the NA core, in OLETF rats compared to LETO rats. These data suggest that CCK-A receptor mechanisms may contribute to the therapeutic and the extrapyramidal motor effects associated with antipsychotic drug treatment.

Animals↗

PubMed2003

Stressor controllability modulates stress-induced serotonin but not dopamine efflux in the nucleus accumbens shell.

The ability of an organism to control a stressor can modulate many of the consequences of stress. Previous research indicates that uncontrollable stress (inescapable shock, IS) activates serotonergic (5-HT) neurons of the dorsal raphe nucleus (DRN) to a greater degree than controllable stress (escapable shock, ES), potentiating 5-HT efflux in the DRN and in target regions. Previous research also indicates that IS selectively affects dopamine (DA) efflux. The present study measured 5-HT and DA efflux in the NAc shell during IS or ES using in vivo microdialysis. Male Sprague Dawley rats with probes in the NAc shell were dialysed while subjected to 100 1.0 mA tailshocks. Rats were run in yoked pairs in wheel-turn boxes such that one rat (ES) in the pair could terminate the shock received by both himself and his yoked (IS) partner by a behavioral response. No stress controls remained in the dialysis bowls. 5-HT efflux selectively increased during IS, and remained increased throughout as well as after the stress session. There was no effect of stress on DA efflux. These results indicate that the NAc 5-HT response is preferentially sensitive to stress and can be modulated by stressor controllability.

Animals↗

PubMed2004

Clozapine and dopamine D3 receptor antisense reduce cocaine- and amphetamine-regulated transcript expression in the rat nucleus accumbens shell.

Cocaine- and amphetamine-regulated transcript (CART) is a neuropeptide highly expressed in the hypothalamus and nucleus accumbens. Hypothalamic CART has been associated with food intake and body weight control, but in the nucleus accumbens the role of CART remains elusive. New generations of antipsychotic drugs show a good efficacy over psychotic symptoms but they induce an important weight gain. The mechanism underlying this unexpected side effect is still unknown. The present results show, for the first time, that acute and chronic treatment with the atypical neuroleptic clozapine, but not the conventional neuroleptic haloperidol, reduced the expression of CART mRNA in the shell of the nucleus accumbens. CART mRNA is colocalized with both dopamine D(2) and D(3) receptor transcripts in the nucleus accumbens shell. However, a dopamine D(3) receptor, but not D(2), antisense oligonucleotide administration reduced CART expression in this brain area. These results suggest that the dopamine D(3) receptor, but not the D(2), is involved in the control of CART expression in the nucleus accumbens and that it may participate in the modulation of CART mRNA levels by clozapine. The modulation of CART, an anorexigenic neuropeptide, in the dopamine mesolimbic pathway may potentially play a role in dysregulated food intake induced by some antipsychotic drugs.

Animals↗

PubMed2000

Purification and characterization of perlucin and perlustrin, two new proteins from the shell of the mollusc Haliotis laevigata.

Two new proteins, named perlucin and perlustrin, with M(r) 17,000 and 13,000, respectively, were isolated from the shell of the mollusc Halotis laevigata (abalone) by ion-exchange chromatography and reversed-phase HPLC after demineralization of the shell in 10% acetic acid. The sequence of the first 32 amino acids of perlucin indicated that this protein belonged to a heterogeneous group of proteins consisting of a single C-type lectin domain. Perlucin increased the precipitation of CaCO(3) from a saturated solution, indicating that it may promote the nucleation and/or the growth of CaCO(3) crystals. With pancreatic stone protein (lithostathine) and the eggshell protein ovocleidin 17, this is the third C-type lectin domain protein isolated from CaCO(3) biominerals. This indicates that this type of protein performs an important but at present unrecognized function in biomineralization. Perlustrin was a minor component of the protein mixture and the sequence of the first 33 amino acids indicated a certain similarity to part of the much larger nacre protein lustrin A.

Amino Acid Sequence↗

PubMed2000

cDNA cloning and functional expression of growth hormone receptor from soft-shelled turtle (Pelodiscus sinensis japonicus).

The growth hormone receptor (GHR) cDNA was cloned from the liver of soft-shelled turtle (Pelodiscus sinensis japonicus) using the polymerase chain reaction (PCR). Although GHR has been cloned from several mammalian and avian species, this is the first description of the reptilian receptor. As deduced from the nucleotide sequence, the precursor GHR of soft-shelled turtle (tGHR) is a protein of 615 amino acids which presents 72% identity with the chicken receptor and 57-64% identity with GHRs of several mammals. The tGHR expressed in COS-7 cells specifically bound human growth hormone (hGH) and was able to transduce an activation of transcription in the transfected cells. Binding of (125)I-hGH to the expressed receptor was decreased by the addition of excess unlabeled hGH, pig GH, and bream GH but not by pig insulin. The open reading frame of tGHR cDNA was inserted into the pSINrep/gfp (green fluorescence protein) vector and the tGHR-gfp fusion protein was stably expressed in baby hamster kidney (BHK) cells. Confocal imaging showed that tGHR-gfp was largely concentrated on the plasma membrane. Western blot analysis and deglycosylation treatment with PNGase F demonstrated that tGHR was a glycoprotein in BHK cells.

Amino Acid Sequence↗

PubMed1999

Preparation of Shell-Core Cu(2)O-Cu Nanocomposite Particles and Cu Nanoparticles in a New Microemulsion System.

Shell-core Cu(2)O-Cu nanocomposite particles and metal Cu nanoparticles are synthesized in a new microemulsion system which consists of saturated Cu(2+) salt aqueous solution dispersed in isopropanol and stabilized by polyvinylalcohol (PVA). The size of the composite particles and the thickness of the Cu(2)O shell layer can be controlled by the volume ratio of isopropanol to H(2)O (the ratio is defined as R). When R >/= 1000, it is available to obtain metal Cu nanoparticles. Copyright 1999 Academic Press.

Journal Article↗