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PubMed1975

[Treatment of idiopathic femur head necrosis with an appropriate cup with cylindrical support].

The objective of treatment of necrosis of the femoral head by means of an appropriate cup is to protect the sequestrum and to avoid secondary arthrosis. Hemispherical cups have a tendency to be easily deformed; cups with cylindrical support should be used in preference as they are mechanically stable and make it possible to cover the femoral head in cases of relatively extensive necrosis. Good results are obtained quickly and are often spectacular : in 90 percent of the cases operated on, pain disappeared or was reduced and normal socio-professional activity was again possible. A clinical and radiological study of 30 hips treated at least 2 years previously, established that the result was stable in the majority of cases : there was one real clinical and radiological deterioration, two cases of pinching of the interspace. This operation is thus worth while in all cases of necrosis, at the stage when the sequestrum is clearly delimited and when there is clear deformation of the contour of the femoral head. It also seems to be worth while at the "eggshell" stage, when the lesions detected at the time of an operation are aften considerable and appear non-reversible : the quality of the results obtained mean that the criteria of tolerance should be much more severe.

Adolescent↗
PubMed1999

Calcium utilization by quail embryos during activities preceding space flight and during embryogenesis in microgravity aboard the orbital space station MIR.

A series of studies were conducted to determine the effect of activities preceding spaceflight and during space-flight on calcium utilization during quail embryonic development. In the pre-space trials, fertile quail eggs were subjected to pre-flight dynamics including forces of centrifugation, vibration, or a combination of vibration and centrifugation prior to incubation for 6 or 16 days. Quail eggs were also tested for survivability in a refrigerator stowage kit for eggs (RSKE) which was subsequently used to transport the eggs to space. Eggs in the RSKE were subjected to shuttle launch dynamics including G force and random vibration profiles. The space-flight trial involved 48 quail eggs launched on space shuttle Flight STS-76 which were subsequently incubated in a Slovakian incubator onboard space station, MIR. Two ground control trials, each with 48 eggs with and without exposure to shuttle launch dynamics were initiated 5 days post-launch. Eggshells from all study trials were retrieved and analyzed for calcium content. Results showed that neither pre-flight activities nor shuttle launch dynamics had an effect on calcium utilization by developing embryos. However, calcium utilization by developing embryos incubated in microgravity was impaired by 12.6% when compared to embryos incubated on earth under laboratory control environment. This impairment was believed to be due to unidentified factors of the microgravity environment.

Animals↗
PubMed2001

Toxicokinetics of waterborne bisphenol A in landlocked salmon (Salmo salar m. sebago) eggs at various temperatures.

Eye-pigmented eggs of landlocked salmon were exposed to waterborne [14C]-labeled bisphenol A at four temperatures (2, 6, 8, and 12 degrees C). Both in accumulation and depuration experiments, the eggs were exposed to a bisphenol A concentration of 1 microg/L for 196 h. In the depuration experiment, the exposed eggs were placed into clean water for 96 h. At each sampling time, the eggs were dissected into three parts (eggshell, embryo, and yolk sac), and all of these parts were weighed and analyzed separately in a liquid scintillation counter. The results show that waterborne bisphenol A accumulates in developing salmon eggs. Accumulation of bisphenol A showed a clear trend both in whole eggs and in dissected parts: the higher the temperature, the higher the uptake rate constant and the concentration of bisphenol A. Steady state was reached only in the embryos at the lowest temperature; in other cases, accumulation was linear. Depuration was significant only in the embryos at 2 and 6 degrees C. As the accumulation and the depuration results show, the elimination of bisphenol A was evidently more significant at lower temperatures.

Animals↗
PubMed1979

Shell thinning and residues of organochlorines and mercury in seabird eggs, Eastern Canada, 1970-76.

Organochlorine and mercury concentrations are reported for 252 eggs of Leach's storm-petrel (Oceanodroma leucorhoa), double-crested cormorant (Phalarocorax auritus), common eider (Somateria mollissima), common tern (Sterna hirundo), razorbill (Alca torda), common murre (Uria aalge) black guillemot (Cepphus grylle), and Atlantic puffin (Fratercula arctica) from the Bay of Fundy, the Gulf of St. Lawrence, and the open Atlantic shore of Canada during 1970-76. Concentrations of all organochlorines except DDE and polychlorinated biphenyls (PCBs) were low. DDE, PCBs, and mercury residues were highest in cormorant and petrel, intermediated in alcids, and lowest in eider and tern. Temporal and spatial aspects of contamination patterns are discussed. Authors conclude that only in cormorants were DDE residues high enough to cause, through eggshell thinning, local population declines.

Animals↗
PubMed2001

Phytate from an alternative dietary supplement has no effect on the calcium, iron and zinc status in undernourished rats.

A mixture of cereal bran, eggshells and cassava leaf powder, known as multimixture (MM), has been widely used in developing countries as a dietary supplement to combat malnutrition in children. The introduction of phytate from cereal bran in infant diets has generated serious controversy about MM due to the mineral chelating effect of phytate. This paper reports on a study to investigate the bioavailability of calcium, iron and zinc in rats fed with a deficient diet supplemented with MM. Undernourished rats were treated with a deficient diet (DD) to which MM containing different phytate and mineral concentrations was added. Body weight gains, Ca, Fe, Zn and phytate balances, blood hemoglobin concentration and the mineral content of tissue were determined. DD supplemented with 5% and 25% of MM increased the rats' hemoglobin blood concentration, fur regrowth, Ca concentration in the femur and promoted body weight gain 40 times higher than did the DD. Extra calcium, iron and zinc added to the diet with 25% of MM did not increase the rats' growth rates. Both the addition of NaCl, KF and KI in MM and the use of dephytinized bran in the MM composition led to a significant increase in the rats' growth (P < 0.0001); however, these changes failed to increase Ca, Fe and Zn bioavailability. Our findings suggest that the Ca, Fe and Zn bioavailability was not affected by the MM phytate content or by the concentrations of NaCl, KF and KI in the diet.

Animals↗
PubMed2002

Turtle sex determination assay: mass balance and responses to 2,3,7,8-tetrachlorodibenzo-p-dioxin and 3,3',4,4',5-pentachlorobiphenyl.

Polyhalogenated hydrocarbons have been implicated in the anomalous sexual differentiation of mammals and reptiles. Here, a temperature-sensitive turtle sex determination assay using the red-eared slider (Trachemys scripta elegans) was used to determine the estrogenic or antiestrogenic activity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 3,3',4,4',5-pentachlorobiphenyl (PCB-126). Neither TCDD nor PCB-126 showed a statistically significant difference in the resulting sex ratios (Fisher's exact test, p < 0.45). As a consequence of the dosing technique (eggshell spotting), the shell retained 90 and 96% of the dose for PCB- 126 and TCDD, respectively, similar to retention of estradiol- 17beta. However, the dosing allowed transfer of sufficient chemical to achieve tissue concentrations that were greater than most concentrations reported for environmentally incurred residues. Similar relative mass distributions of PCB-126 and TCDD were observed in albumin (14-20%), yolk (55-70%), and embryo (16-25%). Relative concentration distributions in the embryo approached those in the yolk, 37 to 40% and 40 to 52%, respectively, while relative concentrations in the albumin remained at 11 to 20%. Lipid-normalized TCDD and PCB-126 concentrations were 30- to 40-fold greater in the embryo than in the yolk. It is hypothesized that nonpassive partitioning processes may have occurred in the embryo.

Animals↗
PubMed2003

Porcelain aorta in coronary artery bypass graft operations: an alternative approach.

Porcelain aorta represents a serious condition for coronary artery bypass graft operations. Here we describe a simple technique to avoid any aortic manipulation during an off-pump coronary artery bypass graft procedure. The right internal thoracic artery is used as the source of blood inflow for single or sequential venous grafts. We have used this technique with good results in 5 elderly patients with eggshell aorta.

Aged↗
PubMed2003

Reproductive and morphological effects of halogenated dimethyl bipyrroles on captive American kestrels (Falco sparverius).

Sixty-four adult captive American kestrels (Falco sparverius) were exposed to a dietary source of halogenated dimethyl bipyrroles (HDBPs), a group of organohalogens proposed to have a natural origin. Adult kestrels were assigned to four treatment groups that were administered a different dose of HDBPs [high, 140 microg/(bird x d); medium, 4.3 microg/(bird x d); low, 0.13 microg/(bird x d); control, 0 microg/(bird x d)]. Exposure began prior to pairing and continued during breeding until approximately 28 d after hatching of the final eggs. Juvenile and adult kestrels accumulated HDBPs in carcass tissue, plasma, and liver. In addition, HDBPs were transferred to yolks during egg development. Low dietary absorption efficiencies (0.011-0.029) indicated that HDBPs were effectively cleared from kestrels either from increased elimination, metabolism, or a combination of the two processes. Reproductive and morphological endpoints examined for HDBP-induced changes included egg volume, egg mass, eggshell thickness, egg fertility, clutch size, liver and whole body mass, antebrachium, central retrice, tarsus, ninth primary, and wing cord lengths. Few statistically significant dose-dependent effects were observed. Hepatic tissue samples from selected individuals underwent histomorphological evaluation. Although the hepatic function was not evaluated specifically in these birds, no clinical signs suggestive of liver disease or gross hepatic anomalies were observed. Only minor histomorphological changes were detected in the hepatic tissue. The lack of serious effects suggests that HDBPs are not an acute reproductive threat to avian populations.

Animals↗
PubMed1992

Structural changes induced by He-Ne laser on the chick embryo ovary.

UNLABELLED: The morpho-histochemical alterations that occur in the chicken ovary at 7 days of incubation after irradiation with He-Ne laser of a potency of 5 mw and at a wavelength of 632.8 nm were studied. The embryos were irradiated for 5 minutes through a window opened in the eggshell and aseptically maintained in incubator for 24 hours. The gonads were dissected out and processed for the following techniques: H/E, PAS, alcian blue, and toluidine blue. CONTROLS: The ovaries were formed by a germinative or superficial epithelium, with germ and epithelial cells, and by primary sex cords compressed between them, although separated by a reduced stroma. The cords contained germ cells The surface coat of the germinative epithelium presented a thin layer of PAS positive, alcianophilic at pH 25 and orthochromatic material. Basement membranes and intercord extracellular substance were also PAS positive. PROBLEMS: Disorganization of the tissue structure was well manifest in irradiated gonads, accompanied by negativization of the histochemical reactions. A lymphocytic infiltration was also found. No structural alterations were observed in germ or epithelial cells. It is concluded that laser radiations would act producing decrease of the mucosubstances associated to the plasma membrane and basement membrane. They would also provoke the appearance of an inflammatory mononuclear infiltration.

Animals↗
PubMed1992

Experimental studies on cardiovascular disorders and cellular Ca handling in shell-less chick embryos.

1. Chick embryos rendered Ca deficient by long-term culture outside the eggshell develop hypertension/tachycardia. 2. In this study, the hypertension of the shell-less (SL) chick embryo has been characterized by comparing their cardiovascular response to adrenergic drugs and cellular Ca handling function with normal (NL) embryos. 3. Before and after the administration of noradrenaline (NA), phentolamine (PA), isoproterenol (IP), and propranolol (PP), blood pressure and pulse rate were measured. 4. Baseline blood pressure was consistently higher in SL embryos. In both embryos, blood pressure was elevated by NA and PP, but lowered by IP and PA. Pharmacological sensitivity to NA and PA was higher in SL embryos. Serum Ca was lower in SL embryos, while myocardial calcium content was not different. At the cellular level, Ca handling was studied using red blood cells (RBC) from SL and NL embryos under varying osmotic and ionic conditions by analysing 45Ca uptake and cell volume regulation. 5. Two features of RBC Ca uptake were apparent: (i) Na-Ca exchange was functional since Ca uptake was dependent on external Na; (ii) Ca uptake was dependent on total ionic electrochemical gradient. The SL RBC had greater ion permeability, more active Na-Ca exchange function and higher Ca pumping out capacity. 6. These systemic and cellular properties of the SL embryo indicate that it is a novel and useful experimental system to study the relationship between Ca homeostasis and the development of hypertension.

Adenosine Triphosphate↗
PubMedDate not supplied

Raman investigation of calcium carbonate bone substitutes and related biomaterials.

The interaction between biomaterials used in surgical procedures and the host bone is not yet perfectly understood. It appears that these problems may have been encountered because of insufficient characterisation of the basic component used in the synthesis of such biomaterials. Calcium carbonate (CaCO3) is interesting for bone filling or regeneration procedures because of its resorbability. The aim of this work is to compare different CaCO3 biomaterials and their basic source with the help of microRaman spectroscopy. Bionacre and Biocoral are analysed. The main bands of carbonate internal modes are observed around 1084-86 and 704-12 cm-1. In the lattice modes region, for both Biocoral and synthetic aragonite, two bands at 206 and 155 cm-1 are observed. The eggshell, oyster shell and synthetic calcite samples exhibit bands at 281 and 155 cm-1. Three bands are present at 280, 206 and 155 cm-1 on the Bionacre sample. The 206 and the 280 cm-1 bands are due to aragonite and calcite forms respectively. Therefore it appears to be a mixture of aragonite and calcite whereas Biocoral is pure aragonite. Additional Raman investigations should be of great interest in evaluating the structural modifications and their influence on the biological behaviour of these biomaterials. Lity index, the percentage of prematurity and of low birth weight are the indices of national health status.

Animals↗
PubMed2004

[Pattern of plasma sex steroid hormone levels during the breeding season of male and female skink: Eumeces chinensis].

Changes in gonadal activity and plasma sex steroid hormone levels in male and female Eumece chinensis during the breeding season were described. The results showed that: The vitellogensis of follicles of female Eumeces chinensis needed the stimulation of 17beta-estradiol (E2). As ovary masses reached peak values between late April and mid-May, E2 levels rose to the top value by late March, and then sharply declined but went up again before preovulation; The physiological functions of plasma progesterone (P) consisted in its oviductal egg retention, embryo development, and eggshell formation. P levels fluctuated near the basic value between mid-March and late April. In mid-May, with the onset of ovulation, plasma P levels rose rapidly, reached peak value by late May and declined sharply after ovulation. Plasma E2 levels declined as plasma P levels rose, showing an inverse relationship between them; In males, plasma Testosterone (T) levels were closely correlated with the maintenance of spermatogenesis activities, male and male combat, sexual display, and mating. Plasma T levels tended to rise after the termination of hibernation, and reached peak value by mid-April. After mid-May, with the testis aggressing, plasma T levels gradually went down and reached bottom value by late June.

Animals↗
PubMed2004

The effects of simulated microgravity on avian embryonic development.

Based on the few reports available, microgravity (MG) can have adverse effects on the early development of vascularised extra-embryonic membranes in avian eggs. Whether gravity or oxygen availability is the stimulus for development of the blood vessels in the chorioallantoic membranes (CAM) remains unclear. Under gravity the blastoderm forms on top of the yolk sac, closest to the oxygen rich region beneath the shell membranes, and from there the CAM buds from an abdominal extension subsequently to form a close contact with shell membranes. Then as the embryo develops it spreads beneath the eggshell surface to maximise the surface area of the CAM vascular bed available for O2 uptake. To investigate how simulated MG influences development of the CAM and embryo we conducted experiments on chicken embryos during incubation in a 3D-clinostat (control or continuous MG treatment at 5 rpm). Further, to determine if CAM angiogenesis is directed towards regions of high O2 tension or gravity we investigated the effects of wax treatment (50% shell surface area) on development in MG. We found that clinostat MG caused embryonic failure between day 0-5 by preventing normal development of CAM-shell membrane complex. Thereafter acute MG promoted increases in CAM mass, but did not affect embryo mass. Preliminary findings suggest that combined acute MG and wax treatment did not significantly affect embryonic growth in either MG or control groups, but retarded CAM growth in control embryos only. Finally, we will present evidence to show that acute and prolonged exposure to MG does not prevent normal growth and hatching, but might have more subtle effects on hatchling physiology, including reduced heart mass.

Acrylic Resins↗
PubMed2005

First single movement of turkey embryos.

UNLABELLED: The purpose of the study was to characterize the first contraction of an isolated muscle in turkey embryo. The space of time of the contraction since beginning of incubation, topography, morphogenesis and histology of the concerned muscle and its mechanical counterpart are described. MATERIAL AND METHODS: From the 3rd day of incubation on until the 6th day the embryos were continuously watched through a cellophane window in the eggshell. The installing of the window followed a certain time schedule to reveal the influence of the experimental conditions. For histology the embryos were fixed in Bouin's fluid, then completely cut in serial sections of 5 microm thickness and stained according to Masson-Goldner's trichrome procedure plus resorcin-fuchsin. Wire frame 3D reconstructions were performed to reveal the topography of the region. RESULTS: A paired muscle 1 mm long and 0.1 mm broad, derived by fusion of the four occipital myomeres, is responsible for the first individual contraction. The contraction produces a stretching in the neck region. The muscle named M. occipitalis primordialis consists of four end-to-end connected groups of mononucleated muscle cells; insofar it looks like early muscle in fishes and amphibians. The muscle contains two types of cells according to the cell nuclei. The elastic rod-shaped notochord represents an endoskeleton. Immediately after contraction it brings the body of the embryo back into its former shape. In the neck region the diameter of the notochord is less and, therefore, the elasticity of notochord is higher than further caudal. The floor plate may prevent damage of the neural tube during excursion of the notochord. The floor plate is flanked by two floor plate posts, which have a filamentous content like the floor plate. Their function may be fastening of floor plate and protection of nerve tissue. The passive pulse movements in the occipital region for 2 days before first contraction are considered to be of importance in orientation and extent of the consecutive active reactions. CONCLUSION: Vital observation accompanying serial section examination showed to be a suitable approach to biomechanical investigations in embryology. It allowed even after nearly 180 years of intensive morphological studies of avian embryos to find a new, up till now not described muscle.

Animals↗
PubMed2005

[Scanning electron microscopy of Paragonimus proliferus].

OBJECTIVE: To identify the species of Paragonimus proliferus with scanning electron microscopy (SEM) based on the surface structure of excysted metacercariae, adult worms and eggs. METHODS: Crabs were collected from the endemic area of P. proliferus and excysted metacercariae were separated. Adult worms at different ages and eggs were obtained from the experimentally infected rats. After being fixed by 2.5% glutardialdehyde and 1% osmic acid, alcohol dehydration, gilded by ion spatter, the specimens were observed under SEM by STEREOSCAN-100. RESULTS: The cuticular spines of excysted metacercariae distributed in single pattern, bayonet-shaped or scale-shaped. There were 6 dome-shape papillae around the rim of the ventral sucker symmetrically arranged. The cuticular spines of different age adult worms distributed in group pattern, relatively denser and more regularly arranged in the anterior part than the posterior part of the worm body. The shape and arrangement of the cuticular spines on adult worms at different ages were basically uniform. The surface of eggshell including the operculum was generally smooth. The shell rim joining the operculum was thick and prominent. A knot-like prominence was observed at the aboperculum end. CONCLUSION: The cuticular spines of both excysted metacercariae and adult worms of P. proliferus show its own characteristics, but the size and shape of the cuticular spines among individuals or different parts of the same specimen show certain differences.

Animals↗
PubMed1991

A proline-rich structural protein of the surface sheath of larval Brugia filarial nematode parasites.

Both cDNA and genomic DNA sequences have been isolated which encode a proline-rich precursor protein of the sheath from microfilariae, the first stage larvae of the filarial nematode parasites Brugia pahangi and Brugia malayi. This 22-kDa protein is soluble only under reducing conditions and is extensively cross-linked by both disulfide and nonreducible bonds. Immunogold electron microscopy shows that the protein is localized exclusively in the sheath, a vestigial remnant of the eggshell, which is retained by and encloses the mature microfilaria. Analysis by Western blotting confirms that the protein is expressed only in microfilariae and adult female worms, although transcripts are detectable only in adult females. The deduced amino acid sequence contains a short N-terminal hydrophobic putative leader sequence, a central repetitive domain that contains 14 copies of a degenerate 5-amino acid repeat with the consensus sequence Met-Pro-Pro-Gln-Gly, and a C-terminal proline-rich domain flanked by clusters of cysteine residues. These clusters can be aligned with cysteine residues implicated in cross-linking of a family of cuticular collagens originally identified in Caenorhabditis elegans but which extends to other nematodes.

Amino Acid Sequence↗
PubMed1991

Embryonic expression of beta-actin-lacZ hybrid gene injected into the fertilized ovum of the domestic fowl.

An experiment was carried out to investigate the expression of cloned DNA injected into the germinal disc of the chick fertilized ovum. The beta-actin-lacZ hybrid gene, MiwZ, was injected, in the closed circular form, into the cytoplasm of the germinal disc at the single-cell stage. The embryos were cultured in vitro, then in recipient eggshells up to day 4 of incubation. The survival rate of the embryos at day 4 was 42% (55/130), and the rate of embryos expressing MiwZ was 64% (35/55). Twenty-two embryos expressed the MiwZ in both embryonic and extraembryonic tissues, while the remainder expressed the MiwZ in only extraembryonic tissues. Mosaic expression was observed in most of the embryos expressing MiwZ in embryonic tissues. Expression throughout all tissues of the embryo including blood cells occurred in one case. In this case, the injected DNA was assumed to have integrated at an earlier stage. The results indicate that it is now possible to investigate the promoter activities of introduced exogenous genes as well as the effect of introduced genes on embryogenesis in early chick embryos. This technique may also facilitate the production of transgenic chicks.

Actins↗
PubMedDate not supplied

Late events in chondrocyte differentiation: hypertrophy, type X collagen synthesis and matrix calcification.

During endochondral bone formation chondrocytes pass through several stages of differentiation which are characterized by cell proliferation, matrix synthesis and cell hypertrophy. Type X collagen is synthesized in vivo after chondrocytes have become hypertrophic, but before abundant mineral accumulates in the cartilage extracellular matrix. The molecule is also present in the uncalcified membranes of the avian eggshell. Type X collagen synthesis increased with the concentration of calcium phosphate deposited in the cell layer of chondrocyte cultures. The addition of calcium chloride to chondrocyte cultures increased the synthesis of type X collagen in a dose-and time-dependent manner.

Animals↗