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PubMedDate not supplied

Aerobic bacterial flora from dead-in-shell chicken embryos from Nigeria.

Dead-in-shell chicken embryos from two commercial hatcheries in Anambra State of Nigeria were investigated for isolation of aerobic bacteria. For this purpose, 79 pooled samples containing 632 dead-in-shell chicken embryos were cultured. From these samples, 23 isolates of Escherichia coli and 25 isolates of Staphylococcus aureus were recorded. Other bacterial species isolated included Micrococcus sp. (fifteen isolates), Klebsiella sp. (thirteen isolates), Pseudomonas sp. (nine isolates), and Proteus sp. (seven isolates). Salmonella, Streptococcus, and Mycoplasma spp. could not be isolated. A high incidence of pathogenic strains of bacteria from dead-in-shell chicken embryos was observed. This suggests that the isolates may have contributed to the embryonic mortality and reduced hatchability recorded in the farms investigated.

Animals↗

PubMed1985

Ultrastructure of eggs of Ascaris lumbricoides Linnaeus, 1758. I. Egg-shells.

Under the light microscope the chitin-protein layer of egg-shells in ascarids appears to be a regular, hyaline and nonstructural layer of 1.5 to 2.00 microns in thickness. The outer uterine layer is usually removed during the preparation. The lipid (ascaroside) layer covers the inner surface of the chitinous layer and seems to be irregularly undulated and regularly thick over the whole surface, with the thickness up to 1 micron. In electron micrographs the fibrous structure of the lipid layer is not evident as a rule. This is probably due to washing the lipids away from this layer during the dehydration of deeper layers of egg-shells that are imperfectly fixed with glutaraldehyde. A very low permeability of the egg-shells is typical of geohelminth eggs. The layer lipid shows a distinct lamellate structure only after a prolonged fixation with osmium at higher temperature. This is supported by the studies using the method of freeze-fracturing.

Animals↗

PubMed1984

Cacao bean shell poisoning in a dog.

Cacao bean shells contain potentially toxic quantities of theobromine, a xanthine compound similar in effects to caffeine and theophylline. A dog, which ingested a lethal quantity of garden mulch made from cacao bean shells, developed severe convulsions and died 17 hours later. Analysis of the stomach contents and the ingested cacao bean shells revealed the presence of lethal amounts of theobromine.

Animals↗

PubMed1984

[Selective incorporation of metals in aragonite and calcite into the shell of Mytilus galloprovincialis in relation to the ionic radius].

The Authors assuming as hypothesis that elements beyond Calcium could be included as carbonate according to crystalline structure of Aragonite and Calcite in the shell of Mytilus g. have verified the selective inclusion of Cr, Mg, Zn, Fe, Cu, Cd, Pb in the biocrystals in relation to their ionic radius. Though the ratio of concentrations of these elements in the shell layers: [Me] calcite/[Me] aragonite ( [C]/[A] ) is significatively greater than 1 for Zn and Mg, significatively less than 1 for Cr and Pb and the no-significative distribution of Cu, Fe, Cd do not allow a sure relationship between the ionic radii of Ca and the investigated elements in the process of shell inclusions. However, authors, do not exclude that these elements may be included differently from the relative aragonitic or calcitic crystalline carbonate structures.

Animals↗

PubMedDate not supplied

Design concepts, indications, and surgical technique for use of the protrusio shell.

Major deficiencies of the medial wall of the acetabulum arising from severe protrusio acetabula, migrated endoprostheses, old central fracture dislocations, and intrapelvic socket protrusions are a serious threat to the success and longevity of total hip arthroplasty. However, excessive strain on the weakened medial wall can be substantially reduced by the use of the protrusio shell. Treatment of existing complications includes augmenting and bone grafting the defect. The surgical technique is demanding but not complex. The protrusio shell is designed to conform to the anatomy of the acetabulum and permits independent positioning of the acetabular component in its optimum attitude. Major bony defects in the medial wall should be occluded by the autografts or allografts in conjunction with the use of the protrusio shell.

Acetabulum↗

PubMed1994

Systolic hypertension in the elderly: long-term lacidipine treatment. Objective, protocol, and organization. SHELL Study Group.

Isolated systolic hypertension (ISH) is a definite risk factor for cardiovascular complications (i.e., cardiac failure, coronary artery disease, and stroke) independent of diastolic elevation. The prevalence of ISH is estimated to be approximately 15-20% in the population above the age of 60 years, and increases with advancing age. The Systolic Hypertension in the Elderly (SHELL) study is planned to evaluate the efficacy and tolerability of lacidipine, matched with the diuretic chlorthalidone, in treatment of ISH in elderly hypertensive patients (EHP). One hundred fifteen Italian centers will participate in the study. Fifty centers are associated with the Società Italiana di Geriatria Ospedaliera and 65 centers are departments of internal medicine or outpatient clinics for management of hypertension. A total of 4,800 patients will be enrolled in the trial. Two subprojects will consist of periodical echocardiographic evaluation and 24-h ambulatory blood pressure monitoring. The primary end point of the SHELL study is the incidence of cardiovascular and cerebrovascular events in EHP with ISH, treated with either lacidipine or chlorthalidone. In particular, the SHELL trial is intended to determine whether lacidipine treatment will significantly reduce fatal myocardial events and total cardiovascular mortality.

Aged↗

PubMed1994

Glycogenic effect of an alkali soluble fraction from sepia shell.

The alkali soluble fraction of the sepia shell possesses both anticonvulsant and hypoglycemic effect. The investigation regarding the fate of the blood sugar during the hypoglycemia revealed that the sepia shell extract acts as a glycogenic agent by mobilising the blood sugar towards liver glycogen reserve through the modulation of the enzymes glycogen phosphorylase a and ab in normal and streptozotocin diabetic mice. The glucose tolerance test (GTT) showed a depression in the GTT curve in experimental mice. The available literature on the biochemistry of the shell reveals that it contains glucosamines and some amino acid residues. The presence of amine group may resemble the sulfonylureas like tolbutamide which also possesses both anticonvulsant and hypoglycemic effect.

Animals↗

PubMed1996

Rapid diagnosis of influenza type A infection: comparison of shell-vial culture, directigen flu-A and enzyme-linked immunosorbent assay.

Two direct antigen detection methods (Directigen FLU A, Becton-Dickinson, Cokeysville, Md. and Influenza A virus ELISA Antigen detection kit, Alpha Biotech, Milano) were compared with isolation by shell-vial cultures for rapid diagnosis of influenza type A virus infection. The three methods were performed using a reference viral suspension consisting of a clinical isolate of influenza type A virus as well as 41 nasopharyngeal aspirates collected from patients with influenza symptoms. Influenza type A virus was recovered from 14 specimens by shell-vials. Ten specimens were positive by Directigen FLU A and 7 by ELISA antigen detection kit. When performed on clinical samples the sensitivity of Directigen FLU A and ELISA was 64.2% and 42.8%, respectively. The limit of sensitivity of the shell-vials, performed on a virus stock suspension titrated by haemagglutinin activity, was 0.06-0.03 HA units/ml at 24 hours or 72 hours after inoculation. Directigen FLU A and ELISA detected as positive a virus stock suspension containing 0.25 HA units/ml and 1 HA units/ml, respectively.

Animals↗

PubMed1995

Modulatory effect of sepia shell extract on activity of glucose-6-phosphatase and alanine amino transferase in diabetic mice.

Alkali extract of sepia shell possesses hypoglycemic effect. The status of glycogen and pyruvate and the activity of glucose-6-phosphatase and alanine amino transferase in liver was studied under the influence of sepia shell extract in both normal and streptozotocin induced diabetic mice. The glycogen concentration was elevated steeply in both and the pyruvate concentration increased substantially in diabetic mice, while the activity of glucose-6-phosphatase and alanine amino transferase was inhibited in normal and diabetic mice. The sepia shell extract enhances glycogenesis and reduces the formation of glucose from metabolic intermediates like pyruvate and glucose-1-phosphate and by suppressing gluconeogenesis.

Alanine Transaminase↗

PubMed1997

Pathogenesis of reduced egg production and soft-shelled eggs in laying hens associated with Leucocytozoon caulleryi infection.

The pathogenesis of reduced egg production with soft-shelled eggs in laying hens naturally infected with Leucocytozoon caulleryi was investigated. Many large schizonts of L. caulleryi schizonts were seen in the ovary and oviducts of chickens. Granulomatous and lymphocytic inflammation, edema, and pressure atrophy were associated with these schizonts. The uterine region that secretes the egg shell exhibited the most severe damage. These lesions in the reproductive organs may explain the mechanism for causing the reduced egg production and soft-shelled eggs in laying hens infected with L. caulleryi.

Animals↗

PubMed1997

Dual ultrastructural localization of mu-opioid receptors and NMDA-type glutamate receptors in the shell of the rat nucleus accumbens.

The effectiveness of NMDA antagonists in modulating the motor and motivational effects of opiates is attributed, in part, to functional associations involving NMDA receptors and micro-opioid receptors (MORs) in the shell of the nucleus accumbens (Acb). To determine the subcellular sites for potential functional interactions between opiate ligands and NMDA receptors in this region, we examined the ultrastructural localization of antipeptide antisera against MOR and the R1 subunit of the NMDA receptor in the Acb shell of the adult rat brain. MOR-like immunoreactivity (MOR-LI) was seen primarily in dendrites, whereas NMDAR1-like immunoreactivity (NMDAR1-LI) was detected more often in axon terminals forming asymmetric synapses. In these profiles, MOR labeling was localized mainly to extrasynaptic plasma membranes, whereas NMDAR1-LI was associated with both synaptic and extrasynaptic sites. Of 307 MOR-labeled processes, 17.9% of the dendrites and 9.4% of the axon terminals also contained NMDAR1-LI. In addition, 24.7% of the dendrites containing only MOR-LI were apposed to NMDAR1-labeled axons or terminals. We conclude that in the shell of the Acb, the output of single neurons can be dually modulated by (1) activation of MOR and NMDA receptors in the same dendrites or (2) combined activation of presynaptic NMDA receptors in afferents contacting dendrites containing MOR. In addition, the colocalization of MOR and NMDAR1 in certain axon terminals in the Acb suggests their dual involvement in the presynaptic release of neurotransmitters in this region.

Animals↗

PubMedDate not supplied

[Isolation of cytomegalovirus from peripheral blood by shell-vial culture. Technical considerations].

BACKGROUND: We performed an study of the possible benefits derived from the use of two vials, incubated for 24 and 72 h respectively, in the isolation of CMV from the leukocyte polymorphonuclear (LPMN) of peripheral blood (viremia) in immunosuppressed patients, using the shell-vial culture technique. MATERIAL AND METHODS: The blood samples with EDTA were fractionated by sedimentation with saline dextran. The LPMN-rich upper layer was used for the isolation of CMV in the shell-vial cell culture (MRC-5 cell line) and to prepare the antigenemia pp65 assay. The cultures were stained at 18-24 h (first vial) and 72 h (second vial) with an indirect immunofluorescence assay with a monoclonal antibody against p72 CMV antigen. RESULTS: We studied 878 blood samples of which 247 (28.1%) were positive for CMV. Of the positive samples, 211 (85.4%) were detected in the first vial, and 220 (89%) in the second vial. Neither of the two vials detected all positive samples. An overall toxicity of 3%, in the positive samples, and 8.5% in positive samples was detected, respectively. Of the 28 toxic samples, 25.9% were detected in the first vial and 85.1% in the second (p < 0.001). The use of the second vial increased the number of positive samples in 14.5% (36 blood samples). CONCLUSIONS: In view of the results obtained in this study it would seem that, in order to obtain the maximum diagnostic yield in the isolation of CMV from LPMN of peripheral blood in immunosuppressed patients by means of the shell-vial culture, it is necessary to inoculate all the LPMN extracted into two vials. The lengthening of the incubation period up to 72 h for one of the vials leads to an increased in the isolation of CMV of 14.5% with a low overall toxicity.

Cytomegalovirus↗

PubMed1998

Interconnections among nuclei of the subcortical visual shell: the intergeniculate leaflet is a major constituent of the hamster subcortical visual system.

The intergeniculate leaflet (IGL), a major constituent of the circadian visual system, is one of 12 retinorecipient nuclei forming a "subcortical visual shell" overlying the diencephalic-mesencephalic border. The present investigation evaluated IGL connections with nuclei of the subcortical visual shell and determined the extent of interconnectivity between these nuclei. Male hamsters received stereotaxic, iontophoretic injections of the retrograde tracer, cholera toxin beta fragment, or the anterograde tracer, Phaseolus vulgaris-leucoagglutin, into nuclei of the pretectum (medial, commissural, posterior, olivary, anterior, nucleus of the optic tract, posterior limitans), into the superior colliculus, or into the visual thalamic nuclei (lateral posterior, dorsal lateral geniculate, intergeniculate leaflet, ventral lateral geniculate). Retrogradely labeled cell bodies identified nuclei with afferents projecting to the site of injection, whereas the presence of anterogradely labeled fibers with terminals revealed brain nuclei targeted by neurons at the site of injection. The IGL projects bilaterally to all nuclei of the visual shell except the lateral posterior and dorsal lateral geniculate nuclei. The IGL also has afferents from the same set of nuclei, except the nucleus of the optic tract. The extensive bilateral efferent projections distinguish IGL from the ventral lateral geniculate nucleus. The superior colliculus, commissural pretectal, olivary pretectal, and posterior pretectal nuclei also project bilaterally to the majority of subcortical visual nuclei. The IGL has a well-established role in circadian rhythm regulation, but there is as yet no known function for it in the larger context of the subcortical visual system, much of which is involved in oculomotor control.

Animals↗

PubMed1998

Imidazenil, a positive allosteric GABAA receptor modulator, inhibits the effects of cocaine on locomotor activity and extracellular dopamine in the nucleus accumbens shell without tolerance liability.

Imidazenil, a benzodiazepine recognition site ligand that acts as partial positive allosteric modulator of gamma-aminobutyric acid (GABA) action at GABAA receptors, inhibits in a dose-dependent manner (0.56-2.5 micromol/kg i.p. to rats) the cocaine-induced increase in dopamine (DA) content in the dialysates of the nucleus accumbens shell and striatum and also inhibits cocaine-induced locomotor activity. Diazepam, a full allosteric modulator of GABA action at GABAA receptors, in a dose of 4.4 micromol/kg i.p. also attenuates the cocaine-induced increase in DA content in the dialysates of nucleus accumbens shell, and striatum and the cocaine-induced locomotor activity. However, imidazenil (2.5 micromol/kg i.p.) fails to reduce spontaneous locomotor activity, whereas diazepam (4.4 micromol/kg i.p.) elicits sedation and ataxia and clearly impairs spontaneous locomotor activity. When added in vitro, both imidazenil and diazepam potentiate the GABA-mediated reduction of the ventral tegmental area DA neuron firing rate. After protracted treatment (14 days/three times a day with an increasing-dose schedule), the inhibitory actions of imidazenil fail to develop tolerance, whereas the actions of diazepam exhibit high tolerance liability. We conclude that imidazenil is devoid of tolerance liability and that, via a GABAA-mediated reduction in the extracellular DA in nucleus accumbens shell, it might reduce the psychomotor activity and reinforcing properties of cocaine.

Allosteric Regulation↗

PubMed1981

Effects of varying chamber construction and embryo pre-incubation age on survival and growth of chick embryos in shell-less culture.

Shell-less culture involves culturing chick embryos with associated yolk and albumen outside of the eggshell and shell membranes. The technique allows direct access to and continuous observation of cultured embryos almost to the time of hatching. The plastic wrap/culture tripod technique described in this paper allows normal embryonic growth and differentiation from 48 hours (in ovo pre-incubation age) through at least 10 days of total incubation. As the duration of in ovo pre-incubation is decreased below 36 hours, there is a concomitant increase in the percentage of grossly abnormal embryos associated with decreased survival and retarded growth and differentiation. Survival of embryos pre-incubated for 72 hours through 13 and 18 days of total incubation is greater than 80% and 40%, respectively. The wrap/tripod technique allows substantially better survival and more normal development of cultured embryos than does the petri dish technique of Auerbach et al. (1974). Embryonic growth in 7.8-cm-diameter chambers is significantly greater than in either larger (10.6 cm) or smaller (5.2 cm) diameter chambers. Some gas exchange through the culture chamber walls appears necessary for optimal embryonic survival and growth. Suspending egg contents in either Safeway or Handi-Wrap plastic wrap (both of intermediate permeability) in 7.8-cm tripods resulted in superior growth and/or survival compared to suspension in Silastic sheeting (high permeability), Saran Wrap (low permeability), glass dishes (nonpermeable), or glass dishes lined with an inner layer of Safeway wrap(nonpermeable).

Animals↗

PubMed1992

Sodium-dependent short-circuit current across the yolk sac membrane during embryonic development in normal and shell-less cultured chicks.

The transepithelial electrical characteristics of the isolated yolk sac membrane of normal in ovo or shell-less cultured chick embryos were investigated. In normal chicks the potential difference (blood side positive relative to yolk side) and short-circuit current of the membrane increased during development. Ouabain (10(-4) M) on the blood side (basolateral side, serosal side) significantly decreased potential difference and short-circuit current but was without effect on the yolk side (brush border side, mucosal side). Substitution of choline for Na+ in the bathing solutions abolished the potential difference and the short-circuit current; when Na+ replaced choline this effect was reversed. Amiloride added to both sides of the yolk sac membrane had no effect on potential difference or short-circuit current. Injection of aldosterone (50 micrograms) and T3 (10 microM) into yolk did not induce amiloride sensitivity. The short-circuit current was not altered by addition of either glucose or alanine to the bath. The short-circuit current of the yolk sac membrane of shell-less cultured embryos was significantly lower than that of normal controls. Addition of Ca2+ to the serosal bathing medium did not reverse the foregoing condition, but decreased the short-circuit current. It is concluded that the yolk sac short-circuit current is Na+ dependent and increases with developmental age in the chick embryo.

Animals↗

PubMed1978

Influence of hen dietary calcium and phosphorus on the integrity of the egg shell as it would influence hatching success and the consequences of preincubation 2, 4, 5-T spraying with and without a high TCDD level.

Commercial strain laying hens were fed practical rations deficient in calcium and/or phosphorus to affect weak shelled eggs. Spraying these eggs prior to incubation with 2, 4, 5-T preparations having extremes in TCDD contamination at 10x recommendation was without effect on all parameters used to evaluate embryological development and subsequent early performance of resultant chicks. Analyses for 2, 4, 5-T residues indicated that the shell though weakened was unaffected as a barrier to herbicide contamination.

2,4,5-Trichlorophenoxyacetic Acid↗

PubMed1984

Collagen in the egg shell membranes of the hen.

Collagen-like proteins have been found in the egg shell membranes of the hen. Materials similar to types I and V collagens were detected in each of the two layers of this membrane, the thick outer membrane and the thin inner membrane. Collagen was extracted by acid-pepsin digestion and isolated by differential salt precipitation. Identification of type-specific collagen-like material was established by coelectrophoresis on SDS-polyacrylamide gels using known collagen standards. These bands were susceptible to digestion by bacterial collagenase. From differential staining of the gels it was estimated that the ratio of collagen types I:V was approximately 100:1. Further confirmation of these biochemical results was obtained with immunofluorescence microscopy using type-specific antisera against chicken types I and V collagen with the indirect sandwich technique. Both the inner and outer shell membranes contained the two types of collagen. Within each membrane, the large, coarse 2.5-micron fibers contained predominantly type I collagen-like material, while type V collagen was mainly associated with the delicate narrower fibers of approximately 0.6-micron diameter. These tended to be concentrated in the inner membrane. At the electron microscopic level, both types of fibers were coated with glycoproteins that stained positively with ruthenium red. The deposition of these collagen-like substances by the hen oviduct on to the surface of the developing egg is an additional example of interstitial-type collagen synthesis and secretion by epithelial rather than by mesenchymal cells.

Animals↗