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An observation of interest is that brother-sister inbreeding appears to have increased the size of protoporphyrin spots of wild type egg-shells in japanese quail. Phenodeviant theory can explain the modalities of trait segregation.
Polychromatism and pigments of five Phasianides egg-shells others than japanese quail are studied. Polychromatism modalities and pigments repartitions are species specific.
The present investigation was carried out to study the efficiency of 8 chemical disinfectants on Salmonella senftenberg in the presence or absence of serum (organic matter) using egg shell as bacterial carrier. The most of the tested disinfectants were effective in the used concentrations after a working time of 60 min. at room temperature. Some quaternary ammonium compounds proved to be not effective.
Four avian adenovirus isolants (Indiana C, DPI-2, IBH-2, and B-3)were examined for pathogenicity in laying birds. None affected shell quality, and only one (IBH-2) had even a minimal effect on egg production (faster decline). Of three isolants tested (Indiana C, DPI-2, and IBH-2), only IBH-2 caused feed intake to be reduced. No other clinical signs were observed during these experiments. Egg transmission, virus excretion, and antibody production were found to mimic patterns reported for serotype-1 avian adenoviruses.
From January through October 1990, state health departments reported 49 outbreaks of Salmonella enteritidis (SE) in the United States to CDC. This report summarizes three SE outbreaks in 1990 that were associated with shell eggs.
Characteristics of Andean gull (Larus serranus) and Puna ibis (Plegadis ridgwayi) eggs laid at 4,400 m in the Peruvian Andes were studied to determine how the conflicting requirements of maximizing O2 availability to the embryo while minimizing excessive losses of water vapor and CO2 have been met by avian populations breeding at high altitudes. Egg masses, linear dimensions, and surface areas of these montane eggs were similar to those of Heermann's gull (Larus heermanni) and glossy ibises (Plegadis falcinellus), but conductance to water vapor (GH2O, standardized to 760 torr) of Andean gull and Puna ibis eggs averaged 74.5% and 68.4%, respectively, of lowland values. The difference in GH2O of Andean gull eggs was caused primarily by a reduction in the number of pores per egg; both an increased shell thickness and a smaller number of pores reduced GH2O of Puna ibis eggs. Since the reduction of GH2O of montane eggs did not fully compensate for the change in barometric pressure (59% of sea level) and the increase in gaseous diffusion coefficients at 4,400 m, the "effective" conductance of the eggs at that altitude was greater than at sea level. Therefore, the eggs lost substantially more water during incubation than did lowland eggs. The modifications in eggshell characteristics of montane eggs may have resulted from selection to increase O2 availability to the embryo.
T.l.c. of esterified egg-shell porphyrin shows a mixture containing protoporphyrin with admixture of significant amounts of coproporphyrin, pentacarboxylic porphyrin and uroporphyrin and other, unidentified, porphyrins. This points to porphyrin biosynthesis taking place in the oviduct epithelium.
Chick embryos were maintained in shell-less culture up to a total age of 15 days. The composition of their blood was analyzed together with the blood from coontrol embryos of comparable degree of differentiation. The blood from cultured embryos had lower hematocrit values; their serum contained a reduced concentration of proteins, phospholipids and total calcium and an increased concentration of inorganic phosphorus. In view of the reduced concentration of proteins and phospholipids, the concomitant hypocalcemia must represent, at least in part, a reduction in the binding capacity of the serum and not only a decrease in the ionic fraction of serum calcium.
The feasibility of using fragments of chorioallantois attached to egg shell (C-S) as an alternative to embryonated eggs for isolating Newcastle disease virus (NDV) was assessed. In paired titrations of 6 strains of virus, embryonated eggs detected an average of 6-to-7-fold greater amounts of virus than did C-S fragments. The efficiency of isolation of viscerotropic velogenic NDV from 240 swab samples was 97% in embryonated eggs and 84% in C-S fragments. Sensitivity differences between the 2 host systems were revealed only in tests of samples expected to contain small amounts of virus. These results suggest that C-S fragments can be reliably used in some but not all instances, thereby relieving logistic constraints sometimes associated with the use of embryonated eggs.
A simple, inexpensive and reliable method for immobilizing yeast invertase on egg shells and on zeolites was developed. The activity of the immobilized preparations when compared with that of native enzyme at varying pH, temperature and substrate concentrations, showed improved stability and sigmoidal kinetic behaviour. The immobilized enzyme could be easily removed from the reaction mixture at any specified time.
Egg-shell powder was added to cosmetics in quantity up to 10%. Such cosmetics did not irritate and sensitize the skin, and had a positive influence on allergologic status of animals.
Investigations were carried out to find out the role of higher and lower ambient temperatures together with short and long photoperiods on ovarian growth and secretion of steroids (estradiol-17 beta and progesterone) in the adult female soft-shelled turtle Lissemys punctata punctata during the preparatory, recrudescent, and quiescent phases of its seasonal reproductive cycle. In each phase, females were treated with 3 degrees C higher and 3 degrees C lower than the mean highest and lowest ambient temperatures in association with short and long photoperiods for short-term (4 week) and long-term (8 weeks or more) durations. Short-term high-temperature treatment significantly stimulated ovarian growth and secretion of estradiol-17 beta during the preparatory phase. Eight-week treatment failed to exercise further stimulation over 4-week treatment, whereas 10-week treatment caused regressive changes of ovary (atresia of follicles). Both short- and long-term high-temperature treatments caused degeneration of ovarian follicles during the recrudescent phase. Low-temperature treatment slowed down ovarian growth and secretion in both the preparatory and recrudescent phases. In the quiescent phase, low- as well as high-temperature treatments exercised little influence over the refractory ovarian growth and secretion. Photoperiod appeared to have no effect on female reproduction in any phase. Thus, high temperature is suggested to have a triggering role on ovarian growth and secretion of estrogen at the early preparatory phase, but once the ovarian function sets in, high temperature seems to have a regressive rather than stimulatory effect on ovarian growth and function.
A series of benzene derivatives (R(1)C(6)H(4)R(2)) has been studied by means of electron capture negative ion mass spectrometry (ECNI-MS), and PM3 quantum chemical calculations. The dissociation channel M(-.) --> Hal(-) + (M - Hal). is analysed from the point of view of symmetry conservation. Generally, a symmetry ban on dissociation may be avoided in at least two ways: (i) out-of-plane vibrations of the halogen atom in the molecular negative ion (MNI), mixing pi- and sigma-states of the anion; (ii) symmetrical in-plane vibration of the C-Hal bond, changing the order of the empty levels in the MNI with subsequent radiationless conversion into a sigma-state. Our analysis shows that neither of them provides a satisfactory explanation of the ECNI mass spectra for chlorobenzene, if one retains the usual assumption that an additional electron goes into the LUMO of the neutral molecule. Thus, it may be concluded that in this case electron capture causes a significant perturbation of the energy ordering of vacant orbitals, thus making the frozen shell approximation inapplicable. Copyright 2000 John Wiley & Sons, Ltd.
Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction patterns were used to analyze the mineral structure and organic matrix composition and thermal behavior of the internal nacreous layer (mother of pearl or nacre) of the shell of the giant oyster Pinctada maxima. Nacre is a natural biomaterial with osteogenic properties. The mineral of nacre is calcium carbonate crystallized as aragonite and it is highly crystallized. The FT-IR spectra showed amide, amine, and carboxylic acid groups in the organic matrix of the whole (organic and mineral) nacreous layer, with the HCO(-)(3) groups possibly at the organic-mineral interface. The insoluble organic matrix remaining after decalcification contained amide, amine, and carboxylic groups. The heated aragonite mineral structure of nacre underwent two transformations (X-ray diffraction), aragonite to calcite at 300-400 degrees C, and calcite to calcium oxide (CaO) at 500-600 degrees C. The organic matrix of nacre was destroyed around 550-600 degrees C, the same temperature as the calcite to CaO transformation, revealing the great thermal stability of the organic matrix and the organic-mineral bonding. This could be an useful feature for the in vivo use of this natural biomaterial as an implant.
Bioactive glass (BG) granules of narrow size are excavated when implanted in mandibular bone of beagles. Bone tissue forms within these internally hollowed particles without a connection to the bone at the margins of the defect. In this study the internal excavation of BG granules was simulated by in vitro immersion experiments. Postimmersion solutions were analyzed for changes in Si, Ca, and P concentrations. Using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and Fourier Transform Infrared (FTIR) spectroscopy, granules were analyzed for compositional, morphologic, and structural changes resulting from immersion. Only when the solution was continuously replenished and only if this solution was composed of electrolyte- and protein-containing serum was excavation achieved. Without solution replenishment, that is, under so-called integral immersion conditions, the solution quickly became saturated in silicon, and the silicon no longer dissolved. When the glass was immersed in a solution with serum, a porous surface structure with fine precipitates was formed, in contrast to a dense surface reaction layer with closely packed globular precipitates that was formed in a solution without serum. The combined effect of continuous solution replenishment and the use of a solution containing serum proteins led to the formation of a surface reaction layer that did not impede continued corrosion. As such, all Si was released, and eventually a hollow Ca-P shell was formed. Thus this study supports the hypothesis that there is a physico-chemical mechanism of Si transport through the Ca-P-rich layer followed by Si dissolution. This mechanism may be operative in vivo and thereby may contribute to the observed in vivo excavation.
We have previously shown that withdrawal from repeated, intermittent infusions of cocaine in Lewis rats results in a long-lasting reduction in dopamine transporter levels in the nucleus accumbens. The reduction is dose-dependent, requires multiple injections as well as about a 10-day withdrawal period. In this investigation, we show that the decrease (34%) occurs in the shell rather than in the core of the nucleus accumbens, and that a second cycle of cocaine administration and withdrawal has no additional effect. Also, there were no changes in transporter binding in the caudate putamen, the olfactory tubercle or the ventral tegmental area. These results indicate that the limbic portions of the nucleus accumbens are involved in neurochemical adaptations during withdrawal from cocaine.
Opiate- and psychostimulant-induced modulation of dopamine transmission in the nucleus accumbens shell (AcbSh) is thought to play a key role in their potent reinforcing and locomotor effects. To investigate the cellular basis for potential functional interactions involving opiates active at the delta-opioid receptor (DOR) and psychostimulants that bind selectively to the dopamine transporter (DAT), we examined the electron microscopic localization of their respective antisera in rat AcbSh. DOR immunoperoxidase labeling was seen primarily, and DAT immunogold particles exclusively, in axon terminals. In these terminals, DOR immunoreactivity was prominently associated with discrete segments of the plasma membrane and the membranes of nearby small synaptic and large dense core vesicles. DAT immunogold particles were almost exclusively distributed along nonsynaptic axonal plasma membranes. Thirty-nine percent DOR-labeled profiles (221/566) either apposed DAT-immunoreactive terminals or also contained DAT. Of these 221 DOR-labeled profiles, 13% were axon terminals containing DAT and 15% were dendritic spines apposed to DAT-immunoreactive terminals. In contrast, 70% were morphologically heterogeneous axon terminals and small axons apposed to DAT-immunoreactive terminals. Our results indicate that DOR agonists in the AcbSh can directly modulate the release of dopamine, as well as postsynaptic responses in spiny neurons that receive dopaminergic input, but act principally to control the presynaptic secretion of other neurotransmitters whose release may influence or be influenced by extracellular dopamine. Thus, while opiates and psychostimulants mainly have differential sites of action, cross-sensitization of their addictive properties may occur through common neuronal targets.
Dopamine D(4) receptors in the nucleus accumbens shell (AcbSh) are thought to play a key role in mediating the locomotor and sensitizing affects of psychostimulants, as well as the therapeutic efficacy of atypical antipsychotic drugs. We used electron microscopic immunocytochemistry to determine the functional sites for endogenous and exogenous D(4) receptor activation in this region. Of 1,090 D(4) receptor-labeled profiles observed in the AcbSh of rat brain, 65% were axons and axon terminals, while 22% were dendrites and dendritic spines. Within axons and terminals, D(4) receptor immunoreactivity was localized to segments of the plasma membrane and membranes of nearby vesicles. The axon terminals were morphologically heterogenous, varying in size and content of either all small synaptic vesicles (ssv), or ssv and large dense-core vesicles. The labeled terminals occasionally formed asymmetric excitatory-type axospinous synapses, but the majority were without recognizable synaptic specializations. In a separate series of tissue sections that were processed for dual-labeling of the D(4) receptor and the catecholamine synthesizing enzyme, tyrosine hydroxylase (TH), 56% of all observed associations were appositions between differentially labeled axonal profiles, and 17% were terminals that contained immunoreactivity for both antigens. Dendritic spines containing D(4) receptor-labeling also received convergent input from TH-immunoreactive terminals and unlabeled terminals forming asymmetric synapses. These results provide the first ultrastructural evidence for a major presynaptic, and a more minor postsynaptic, involvement of D(4) receptors in dopaminergic modulation of excitatory transmission in the AcbSh.