OBJECTIVE: Melatonin, which is secreted by pineal gland play an important role in the regulation of ovarian function via seasonal rhythm and sleep in most mammals. It also has a role in the protection of cells by removing toxic oxygen free radicals brought about by metabolism. In the present study, effects of melatonin on the mouse oocyte maturation were examined using two different culture conditions provided with 5% or 21% oxygen concentration. MATERIAL AND METHOD: Immature mouse oocytes were obtained from the ovarian follicles of 3~4 weeks old ICR strain mice intraperitoneally injected with 5 I.U. PMSG 44 hour before. Under stereomicroscope, morphologically healthy oocytes with distinct germinal vesicle (GV) were liberated from the graafian follicles and collected using mouth-controlled micropipette. They were then cultured for 17 hour at 37degrees C, 5% CO2 and 21% O2 (95% air) or 5% CO2, 5% O2 and 90% N2. New modified Hank's balanced salt solution (New MHBS) was used as a culture medium throughout the experiments. Effects of melatonin were examined at a concentration of 0.0001 micrometer, 0.01 micrometer or 1.0 micrometer. For the prevention of spontaneous maturation of immature oocytes during culture, dibutyryl cyclic AMP (dbcAMP) and/or hypoxanthine were included in the medium. RESULTS: Under 21% oxygen condition, oocytes cultured in the presence of 0.01 micrometer melatonin showed a significantly higher maturation rates, in terms of germinal vesicle breakdown (95.0% vs 89.0%) and polar body formation (88.1% vs 75.4%), compared to those cultured with 0.0001 micrometer or 1.0 micrometer melatonin. However, no difference was observed in oocytes cultured under 5% oxygen whether they were treated with melatonin or not. In the presence of 0.01 micrometer melatonin, oocytes either cultured under 21% or 5% oxygen exhibited no difference in the polar body formation (85.6% vs 86.7%). However, in the absence of melatonin, oocytes cultured under 21% oxygen exhibited lower polar body formation (74.7%). When oocytes were cultured in the presence of dbcAMP alone or with varying concentrations of melatonin, those treated with both compounds always showed better maturation, i.e., germinal vesicle breakdown and polar body formation, compared to those cultured with dbcAMP alone. At the same concentration of melatonin, however, oocytes exposed to 21% oxygen showed poor maturation than those to 5% oxygen. Similar results were obtained from the experiments using hypoxanthine instead of dbcAMP. CONCLUSION: Based upon these results, it is suggested that melatonin could enhance the meiotic maturation of mouse oocytes under 21% oxygen concentration, and release oocytes from the meiotic arrest by dbcAMP or hypoxanthine regardless of the concentration of oxygen, probably via the removal of oxygen free radicals.
Animals ; Bucladesine ; Female ; Free Radicals ; Hypoxanthine ; Mammals ; Melatonin* ; Metabolism ; Mice* ; Oocytes* ; Ovarian Follicle ; Oxygen ; Pineal Gland ; Polar Bodies ; Seasons

No abstract available.
Animals ; Mice* ; Microinjections* ; Zygote*

No abstract available.
Animals ; Horns* ; Knee ; Menisci, Tibial*

No abstract available.
Dermatitis, Atopic*

PURPOSE: We evaluated internal and marginal features of solitary pulmonary nodules on CT to differentiate between benign and malignant pulmonary nodules. Materials and Uethods:CT findings of 43 cases with solitary pulmonary nodule were reviewed, restrospectively. Independent T-test between benign and malignant nodules was used. RESULTS: Twenty-one cases were proved as benign nodules and 22 cases as malignant. CT air bronchogram was observed more frequently in the malignant lesions(36.4%) than in the benign ones (p=0.01). ,Air bubble shadow was observed in 5 cases of benign nodule, whereas none of the malignant lesions revealed it. Internal homogeneity or central low density was not different between the two groups. Cavitation was observed in 3 cases of tuberculoma and in 1 case of adenocarcinoma. Calcification was observed in 7 cases of benign and in 2 cases of malignant lesions. Differences in these two features were not statistically significant Mean size of malignant nodules was 3.23cm, and was larger than 2.16cm of benign nodules (p=0.002). Margin of benign nodules was more smooth (42.9%) than that of malignant nodules (p=0.01), and malignant nodules showed more Iobulated contour (90.9%) than benign nodules (42.9%) (p=0.00). The incidence of spiculation was not significantly different (benign 85.7% vs malignant 86.4%). Statistically, pleural tail and satellite lesions were not significantly different between two groups. CONCLUSION: Lobulated margin and CT air bronchogram are the most suggestive findings of malignant pulmonary noule on chest CT.
Adenocarcinoma ; Incidence ; Solitary Pulmonary Nodule* ; Tomography, X-Ray Computed ; Tuberculoma

No abstract available.
Knee ; Ligaments* ; Magnetic Resonance Imaging

With an aging population, osteoporotic vertebral collapse is an increasingly common condition. This compression fractures has been considered a benign entity, quite responsive to conservative treatment. In a rare patients, however, a major neurologic complication and painful kyphosis despite conservative treatment can develop. Therefore, the purpose of this present study is to analyze the surgical results of 14 patients with severe back pain, an increasing kyphosis and neurologic deficits caused hy osteoporotic vertebral collapse following minor trauma, who were treated surgically. Presenting signs and symptoms included severe back pain with progression of kyphosis in 6 patients and increasing neural deficit in 8 patients. Of 14 patients, eight patients had an intravertebral cleft sign (vacuum sign). Indications for surgery included increasing kyphotic deformity, intractable pain, or increasing neurologic deficit. There was no correlation between intravertebral cleft sign and neurologic deficit. However, patients who had intravertebral cleft sign had not well respond to conservative treatment. As treatments, combined anterior and posterior fusion in 8, anterior fusion in 4, posterior instrumentation, and wide decompressive laminectomry in one patient, respectively, were carried out. The final correction of the deformity averaged 0.3 degrees. Therefore. correction of kyphosis was not favorably maintained because of variable surgical methods, and sinking of graft bone or instrumentation into the osteoporotic vertebral bodies. However, pain was reduced significantly in all patients. In addition neurological symptoms improved in 7 patients. One patient underwent reoperation with nnterior inierbody tusion together with anterior instrument because of an increasing kyphosis, neurologic. iymptoms and scvcre hack pain following wide decompressive laminectomy. There was no complication relatecl to instruments. The authors strongly helieved that surgical intervention has highly satisfactory results in patients who have intravertehral cleft sign with persistent back pain despite conservative treatment, and proressive or persistent neurologic deficits following osteoporotic vertebral collapse.
Aging ; Back Pain ; Congenital Abnormalities ; Fractures, Compression ; Humans ; Kyphosis ; Laminectomy ; Neurologic Manifestations ; Osteoporosis ; Pain, Intractable ; Reoperation ; Transplants

No abstract available.
Sinus of Valsalva*

No abstract available.