OBJECTIVE: To determine whether there is a re-closure capacity of the open neural tube defect(ONTD) and to characterize its re-closing process, the morphological changes and the re-closure rate of a surgically induced ONTD are examined chronologically in early chick embryos. METHODS: Embryos of Hamburger and Hamilton stage 18-19 were used. The posterior roof of the central canal in the closed neural tube was incised longitudinally at the wing bud level. The incision was 3 somites long, which was equivalent to approximately 0.8mm. Following surgery, the embryos were re-incubated in ovo for three or five days. The area of the incision was observed with a stereomicroscope. Some of them were examined histologically with the transverse section of the wing bud area. They were divided into two groups(POD 3 and POD 5) according to the re-incubation period at the time of sacrifice and then into two subgroups(re-closure and defect group) according to the presence of ONTD at the operative site. RESULTS: The results showed : 1) Re-closure of ONTD occurred in 58%(23/40) of POD 3 embryos and 46%(22/48) of POD 5 embryos. The difference of re-closure was not statistically significant. 2) Most of the re-closed neural tubes revealed no significant difference from the controls in the histological examination. 3) In POD 3 and 5 groups, there was a tendency of zipper-like fusion in both re-closure and defect groups. CONCLUSION: The results of study showed that the neural tube of the early chick embryo has a re-closure capacity after being surgically reopened. Seemingly, re-closure occurs mainly before POD 3 and progresses from the ventral to the dorsal part of the neural tube. The mechanism of re-closure needs to be investigated further.
Animals ; Chick Embryo* ; Embryonic Structures ; Neural Tube Defects* ; Neural Tube* ; Somites ; Wings, Animal

OBJECTIVE: To investigate the effects of bisphenol A (BPA) on cell death pattern in neuronal development of chick embryos. MATERIALS AND METHODS: We planned to compare the cytokinetic features in the normal chick embryo and those with BPA. Fifteen eggs were divided into three GROUPS: the control group, BPA 50 microgram/g egg group and BPA 200 microgram/g egg group. Embryos were incubated for 56 hours (Hamburger & Hamilton stage 16) and then we injected BPA into embryos. The embryos were sectioned by 3 micrometer thickness at the level of wing buds and stained at 72 hours after incubation (HH stage 18). We observed cell death in the spinal cord using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method. RESULTS: The TUNEL-positivity markedly increased in proportion to the doses of BPA. The number of TUNEL-positive cells per section was 15.2+/-2.14 in the control group, 34.6+/-3.44 in the BPA 50 microgram/g egg group, 87.6+/-4.32 in the BPA 200 g/g egg group. Furthermore the contour of spinal cord was deformed as the doses of BPA raised. CONCLUSION: BPA causes neuronal cell death and exerts cytotoxic effect on early chick embryos. It suggests that BPA might have an effect on cytogenesis during neural tube development.
Animals ; Apoptosis ; Benzhydryl Compounds ; Cell Death ; Chick Embryo ; Eggs ; Embryonic Structures ; Neural Tube ; Neurons ; Ovum ; Phenols ; Spinal Cord ; Wings, Animal

OBJECTIVE: The animal research of embryonic teratogenesis is widely performed and the neural tube defects are also studied through various animal models. Particularly, the experimental research on chick embryos is performed with great popularity. In this experiment we studied the effect of albumen removal and the needle puncture on the development of neural tube defects in chick embryos. METHODS: The domestic hen eggs of control group are incubated for 14 days at 37.5degreesC and 70% humidity. The experimental group was divided into three groups, needle puncture group, 5 cc albumen removal group and 10 cc albumen removal group after the eggs were incubated for 24-28 hours and incubated for another 13 days after the puncture with or without albumen removal. After 14 days of incubation, all the embryos were isolated and morphologically characterized. RESULTS: Of 39 incubated chick embryos in control group, 31 embryos were grown as normal and 8 embryos were grown as anomalous. The numbers of total(normal/anomalous/developmentally arrest) embryos of each group were 37(14/16/7), 37(9/17/11), and 37(6/13/18) in the needle puncture, 5cc albumen removal and 10cc albumen removal groups, respectively. Needle puncture increased the teratogenesis of chick embryos significantly but did not increase the neural tube defect. In cases of 5 cc albumen removal, the teratogenesis of chick embryos was increased to a significant level and the incidence of neural tube defect was increased significantly. In cases of 10 cc albumen removal, not only teratogenesis but also growth arrest were increased markedly. Therefore, it was not considered to be an adequate experimental model. CONCLUSIONS: This results indicate that needle puncture itself to remove the albumen from chick embryos had nothing to do with the neural tube defects and therefore its effect can be excluded. Needle puncture and albumen removal cause not only neural tube defects but other malformations such as abdominal wall defects, developmental arrest, and malformation of eyes.
Abdominal Wall ; Animal Experimentation ; Animals ; Chick Embryo* ; Eggs ; Embryonic Structures ; Humidity ; Incidence ; Models, Animal ; Models, Theoretical ; Needles* ; Neural Tube Defects* ; Neural Tube* ; Ovum ; Punctures* ; Teratogenesis

AIMThe production of interspecific germline chimeras between chicken and quail were attempted employing the dissociated cells derived from the blastodermal central disk (stage X) and the germinal crescent region of embryo (stage 7-8).

METHODSThe central disk (CD) of the area pellucida in chicken blastoderm (stage X) and the germinal crescent region (GCR) of embryo (stage 7-8) were dispersed and injected into the subgerminal cavity of quail blastoderm (stage X). Injected eggs were incubated for 7 days or to hatching. The donor chicken DNA was detected by the polymerase chain reaction.

RESULTSIn day-7 embryos, chicken DNA was detected in 5 gonads and 9 brains from 53 survived embryos received chicken CD cells, and 1 gonads and 6 brains from 27 survived embryos received chicken GCR. Chicken DNA was also detected from the semen of one adult male hatched from eggs received chicken GCR cells.

CONCLUSIONCD and GCR cells as the donors showed the possibility to produce the interspecific germline chimera, but further studies are needed to make necessary improvement.

Animals ; Base Sequence ; Blastoderm ; physiology ; ultrastructure ; Brain ; embryology ; Brain Chemistry ; Chick Embryo ; physiology ; Chickens ; Chimera ; DNA Primers ; DNA, Complementary ; genetics ; Embryo, Nonmammalian ; physiology ; Female ; Germ-Line Mutation ; physiology ; Male ; Ovalbumin ; genetics ; Ovary ; embryology ; Polymerase Chain Reaction ; Quail ; Testis ; embryology

The present study was performed to evaluate the effect of tetracycline-HCl on the change of implant surface microstructure according to application time. Implant with pure titanium machined surface, HA-coated surface and dual acid etched surface were utilized. Implant surface was rubbed with 50mg/ml tetracycline-HCL solution for 1/2min., 1min., 1 1/2min., 2min., and 2 1/2min. respectively in the test group. Then, specimens were processed for scanning electron microscopic observation. The results of this study were as follows. 1. Both test and control group showed a few shallow grooves and ridges in pure titanium machined surface implants. There were not significant differences between two groups. 2. In HA-coated surfaces, round particles were deposited irregularly. The roughness of surfaces conditioned with tetracycline-HCL was lessened and the cracks were increased relative to the application time. 3. The etched surfaces showed the honey comb structures. The surface conditioning with tetracycline-HCl didn't influence on its micro-morphology. In conclusion, the detoxification with 50mg/ml tetracycline-HCl must be applied respectively with different time according to various implant surfaces.
Animals ; Comb and Wattles ; Honey ; Titanium

Trichonodosis(knotted hair) is a disorder of the hair shaft that can comprise a single or double knot. Reports of trichonodosis are not cornmon in dermatological literature, but it is generally considered not to be rare. Two varieties of trichonodosis have been described. A rare type occurs in association with abnormally growing scalp and body hair that tends to splinter and fracture. A more comrnon form occurs when normal hair is subjected to rnechanical forces, such as combing and brushing. Trichonodosis occurs exclusively in persons with curly or kinky hair. We report a patient with short, straight hair and trichonodosis. The most likely cause in our patient is trauma as a result of continual rubbing of hairs.
Animals ; Comb and Wattles ; Hair ; Humans ; Scalp

The purpose of this study was to evaluate the shear bond strength of three kinds of different ceramic brackets with three different bonding adhesives. 5 specimens for each combination were tested for shear bond strength using Instron and for fracture site using SENL And 3 specimens were cross-sectioned for SEM examination of bonding pattern between bracket, resin and enamel surface. The results were as follows 1. The shear bond strength of chemical curing adhesives were higher than that of light curing adhesives. 2. The shear bond strength of Starfire bracket, chemical-bonded type, was lower than that of Transcend bracket, mechanical-bonded type, and Fascination bracket, combined type. 3. Fracture site of each bracket and tooth surface was examined under a light optical stereoscopic microscope, Transcend groups were mainly at the E/R intderface. Fascination groups were mainly at the COMB interface and Starfire groups were mainly at the R/B interface.
Adhesives* ; Animals ; Ceramics* ; Comb and Wattles ; Dental Enamel ; Tooth

Ganglia are ubiquitous but periosteal ganglion is rare. This case is presented showing an unusual radiological picture. The radiological picture with honey combed appearance is striking. Previaus reports have stressed the concavity in the cortex. Histologically the structure is identical to that of soft tissue ganglia.
Animals ; Comb and Wattles ; Ganglia ; Ganglion Cysts ; Honey ; Strikes, Employee

BACKGROUND AND OBJECTIVES: Laboratory research was carried out to investigate the teratogenic effect of X-ray on chick embryos, especially with regard to cardiovascular malformation. MATERIALS AND METHODS: The chick embryos, 242, 242 and 215 eggs, were irradiated with X-ray at the dose of 500, 750 and 1000 cGy, respectively, during the incubation period between 0 and 9 days. A control group of 90 eggs received no irradiation. After 2 weeks of incubation, the embryos were sacrificed and examined. RESULTS: The survival rate of irradiated group was significantly lower than that of control group (62.5 vs. 87.8%, p<0.0001). The incidence rate of cardiovascular malformation was significantly higher in the irradiated than the control group (16.2 vs. 2.5%, p<0.005). The rate of cardiovascular malformation in the irradiated group increased from 9.4% with 500 cGy to 24.5% with 1000 cGy (p<0.05). There were a total of 33 cases of cardiac malformation, of which 24 were ventricular septal defects and 9 were complex congenital heart diseases. The higher the administered dose of radiation, the higher the observed incidence rate of cardiac malformation and the more complex the cardiac anomaly. Also, the rates of exocardia, exencephaly, beak anomalies and anopia were all increased in the irradiated group. CONCLUSION: X-ray irradiation of chick embryos increased the rates of death and cardiovascular malformation. The highest dose resulted in greater complexity of the cardiovascular malformation.
Animals ; Beak ; Cardiovascular System* ; Chick Embryo* ; Eggs ; Embryonic Structures ; Heart ; Heart Diseases ; Heart Septal Defects, Ventricular ; Incidence ; Neural Tube Defects ; Ovum ; Survival Rate

We have expressed GFP in Sf9 and Bm5 cells or Bombyx by larvae by using Ac-Bm hybrid virus capable of replicating in both Bm5 and Sf9 cells. Genomic DNA of Ac-Bm hybrid virus expressing P-galactosidase was cotransfected with baculovirus transfer vector containing GFP gene, pBacPAK-GFP in Sf9 cells. The Ac-Bm hybrid virus harboring GFP was named as Ac-Bm hybrid virus-GFP. The Ac-Bm hybrid virus-GFP-infected insect cells were easily selected by detecting the emission of GFP from each well of cell culture dish on the UV illuminator. GFP produced by Ac-Bm hybrid virus-GFP in Sf9 and Bm5 cells or B. mori larvae was confirmed by SDS-PAGE and Western blot analysis using GFP antibody. In addition, B. mori larvae infected with Ac-Bm hybrid virus-GFP was apparently appeared fluorescence from the whole body at 5 days postinoculation. The fluorescence of GFP from the hemolymph and fat body of B. mori larvae infected with Ac-Bm hybrid virus-GFP was also observed by fluorescence microscope. In conclusion, our results demonstrated that in baculovirus expression vector system, use of Ac-Bm hybrid virus have an additional advantage of expanded host range for producing recombinant proteins.
Animals ; Baculoviridae ; Blotting, Western ; Bombyx* ; Cell Culture Techniques ; DNA ; Electrophoresis, Polyacrylamide Gel ; Fat Body ; Fluorescence ; Hemolymph ; Host Specificity ; Insects ; Larva* ; Recombinant Proteins ; Sf9 Cells ; Spodoptera*