No abstract available.
Animals, Laboratory

PURPOSE: It has been recognized that interaction of the Fas : Fas ligand plays an important role in radiation-induced apoptosis. The purpose of this study was to investigate the role of Fas mutation in radiation-induced apoptosis in vivo. MATERIALS AND METHODS: Mice with mutations in Fas, MRL/Mpj-Fas(lpr), and its normal control, MRL/Mpj, were used in this study. Eight-week old male mice were given whole body radiation. After irradiation, the mice were killed and their spleens were collected at different time intervals. Tissue samples were stained with hematoxylin-eosin and the numbers of apoptotic cells were scored. Regulating molecules of apoptosis including p53, Bcl-2, Bax, Bcl-XL, and Bcl-XS were also analyzed by Western blotting. RESULTS: At 25 Gy irradiation, the level of apoptosis reached the peak value at 8 hr after radiation and recovered to the normal value at 24 hr after radiation in MRL/Mpj mice. In contrast, the peak apoptosis level appeared at 4 hr after radiation in MRL/Mpj-Fas(lpr) mice. At 8 hr after radiation, the levels of apoptosis in MRL/Mpj mice and MRL/Mpj-Fas(lpr) mice were 52.3+/-7.8% and 8.0+/-8.6%, respectively (p<0.05). The expression of apoptosis regulating molecules, p53, Bcl-XL and Bcl-XS, increased in MRL/Mpj mice in response to radiation; p53 with a peak level of 3-fold at 8 h, Bcl-XL with a peak level of 3.3-fold at 12 h, and Bcl-XS with a peak level of 3-fold at 12 h after 25 Gy radiation. Bcl-2 and Bax did not show significant change in MRL/Mpj mice. However in MRL/Mpj-Fas(lpr) mice, the expression levels of p53, Bcl-2, Bax, Bcl-XL and Bcl-XS showed no significant change. CONCLUSION: The level of radiation-induced apoptosis was lower in Fas mutated mice, lpr, than in control mice. This seemed to be related to the lack of radiation-induced p53 activation in the lpr mice. This result suggests that Fas plays an important role in radiation-induced apoptosis in vivo.
Animals ; Apoptosis* ; Blotting, Western ; Fas Ligand Protein ; Humans ; Male ; Mice ; Radiation Dosage ; Reference Values ; Spleen ; Whole-Body Irradiation

PURPOSE: Although adjuvant chemotherapy reduces the risk of disease recurrence in stage III colon cancer patients, published guidelines do not specify when it should be initiated. This study aimed to assess the effect of adjuvant chemotherapy initiation time on disease recurrence and survival in stage III colon cancer patients undergoing curative surgical resection. METHODS: The medical records of stage III colon cancer patients undergoing curative resection between February 2004 and December 2009 were reviewed. RESULTS: Of the 133 enrolled patients, 27 (20.3%) began adjuvant chemotherapy within 3 weeks of surgery, whereas 106 (79.7%) did after 3 weeks following surgery. Patients receiving chemotherapy within 3 weeks of surgery were less likely to experience recurrences than those beginning treatment later (11.1% vs. 33%, P = 0.018). The mean disease-free survival of patients receiving adjuvant therapy earlier was 54.6 months, whereas that of patients with later treatment was 43.5 months (P = 0.014). However, no significant differences in overall survival were observed between the 2 groups. CONCLUSION: Adjuvant chemotherapy should be initiated as soon as a patient's clinical condition allows. Patients with stage III colon cancer may benefit from adjuvant chemotherapy initiated within 3 weeks of surgery.
Chemotherapy, Adjuvant* ; Colon* ; Colonic Neoplasms* ; Disease-Free Survival ; Drug Therapy ; Humans ; Medical Records ; Prognosis ; Recurrence

BACKGROUND: The goal of successful resuscitation is not only to stop the process of ischemia as soon as possible but also to overcome the secondary injury process after resuscitation, which involves a complex interplay of mechanisms. Brain damage accompanying cardiac arrest and resuscitation is frequent and devastating. Cells die by one of two mechanisms: necrosis or delayed neuronal death. Delayed neuronal death may require protein synthesis. Neurons in the CA1 subfield of the hippocampus are selectively vulnerable to death after injury by ischemia and reperfusion. Death of these neurons occurs after an interval of 1 or 2 days. We assessed the effects of a protein synthesis inhibitor, cycloheximide(CHX), on hippocampal neuronal death of rats by using the ventricular fibrillation cardiac arrest(VFCA) model. METHODS: The effect of CHX(3mg/kg, s.c.) on hippocampal neuronal death was studied in two groups of 18 rats each, one group being subjected to a 2-min VFCA and the other to a 3-min VFCA. Each group was divided into three subgroups: control(group I,II) without subcutaneous injection of CHX, 'exp-12' of group I/II treated with CHX 12 hours after return of spontaneous circulation (ROSC), and 'exp-24' of group I/II treated with CHX 24 hours after ROSC. The coronal sections of the hippocampus levels were stained with hematoxylin-eosin after 72 hours of survival. The histologic damage score(HDS) was used to assign a score to the total number of damaged neurons counted in each of the hippocampal CA1 subfields. RESULTS: 1. There were not significan differences in heart rates, blood pressures, blood sugar, and blood gas in group I & II during the pre-arrest steady state or at 5 min and 30 min after ROSC. 2. In group I & II, the HDS, were significantly reduced in rats(I exp-12, 1.1+/-0.6; I exp-24, 1.3+/-0.5; II exp-12, 1.4+/-0.7; and II exp-24, 1.8+/-0.8) treated with CHX 12 hours or 24 hours after ROSC than control rats(I, 2.5+/-0.9, II, 2.9+/-0.8)(p<0.05). CONCLUSION: These results suggest that delayed hippocampal neuronal death from ischemic insult after ventricular fibrillation cardiac arrest followed by resuscitation can be prevented by a protein synthesis inhibitor, CHX. Further experimental studies of the action mechanism of protein synthesis inhibitors to delayed neuronal death and clinical applications are required.
Animals ; Blood Glucose ; Brain ; Heart Arrest* ; Heart Rate ; Hippocampus ; Injections, Subcutaneous ; Ischemia ; Necrosis ; Neurons* ; Protein Synthesis Inhibitors ; Rats* ; Reperfusion ; Resuscitation ; Ventricular Fibrillation*

OBJECTIVE: In acute spinal cord injury, biomechanical and pathological changes in the cord may worsen after injury. To explain these phenomena, the concept of the secondary injury has evolved and numerous pathophysiological mechanisms have postulated. These, however, have mainly focused only on the cell necrosis. The aim of present study is to verify whether apoptosis plays a role in the animal model of secondary injury of spinal cord. MATERIALS AND METHODS: Adult male Sprague-Dawley rats were laminectomized and spinal cord injury was induced using NYU spinal impactor at T9 segment. The animals were sacrificed periodically and tissue specimen was obtained at the injury segment, adjacent segments, and remote segments to observe the secondary injury ultimately for the observation of the spatial and temporal distribution and the related cells for the appearance of apoptosis, if present. RESULTS: In the spatial distribution of apoptosis, the apoptotic cells were located at gray matter of spinal cord and the number of apoptotic cells were significantly higher in adjacent segments than in the injured segment. In the temporal distribution of apoptosis, the number of apoptotic cells were maximal at 4 hours after injury and decreased subsequently. No apoptotic cells were found at remote segments which implies that there were no influence of apoptosis on transneuronal degeneration. CONCLUSION: These results suggest that the lesioned area of spinal cord expanded over time in acute spinal cord injury and apoptosis contributed to the spinal cord neuronal and glial cell loss. In conclusion, apoptosis is thought to have an important role in secondary injury of acute spinal cord injury.
Adult ; Animals ; Apoptosis ; Cell Death* ; Humans ; Male ; Models, Animal ; Necrosis ; Neuroglia ; Neurons ; Rats, Sprague-Dawley ; Spinal Cord Injuries* ; Spinal Cord*

BACKGROUND: Vascular lesions are the major cause of morbidity and mortality in hypertensive patients. However, the pathologic characteristics of gradually evolving, chronic hypertension have not been adequately studied and the mechanism by which hypertension accelerates atherosclerosis is still uncertain. This study was undertaken to invertigate the ultrastructural changes of the aorta and the effect of high cholesterol diet in spontaneously hypertensive rats(SHR). METHODS: Spontaneously hypertensive rats (n=80, male, 5 weeks old) and Wistar rats (n=40, male, 5 week old) were used. Forty SHR were fed with 2% cholestrol diete, while the remainder with control diet. Systolic blood pressure was measured weekly until 16 weeks after birth, and then biweekly until 40 weeks after birth. Transmission and scanning electron microscopy were used to evaluate ultrastrucural changes of the aorta. RESULTS: 1) The blood pressure of SHR rose stedily and progressively from the 5 weeks after birth and reached nearly 190mmHG at the 16 weeks after birth. 2) In SHR, the subendothelial component contained finely granular substances, abundant fibrillar collagen and elastin. Infiltration of the mononuclear blood leukocytes into the intima was frequently seen. 3) Endothelium from cholestrol-fed SHR did exhibit numerous pinocytotic vesicles and contained many cytoplasmic filaments. There were a number of large mononuclear lipid-filled cells in the intimal lesions. Blistering of the endothelial plasma membrane was also observed in high cholesterol diet-fed SHR. Later on, adhesion of platelets, febrin, and white blood cells as well as damage of intima shown as multiple small holes were more marked. 4) There was no significant difference in systoloic blood pressure between high cholesterol diet-fed and control diet-fed SHR. CONCLUSION: In the aorta of SHR, the most prominent change was an expansion of the subendothelial space and infiltration of the mononuclear leukocytes into the intima. The present study showed that the SHR was indeed a reliable model for the essential hypertension. In some SHR, high cholesterol diet could induce more pronounced vascular lesions, which were enhanced by hypertension.
Aorta* ; Atherosclerosis ; Blister ; Blood Pressure ; Cell Membrane ; Cholesterol* ; Cytoskeleton ; Diet* ; Elastin ; Endothelium ; Fibrillar Collagens ; Humans ; Hypertension ; Leukocytes ; Leukocytes, Mononuclear ; Male ; Microscopy, Electron ; Microscopy, Electron, Scanning ; Mortality ; Parturition ; Rats, Inbred SHR* ; Rats, Wistar

The X-ray synchrotron is quite different from conventional radiation sources. This technique may expand the capabilities of conventional radiology and be applied in novel manners for special cases. To evaluate the usefulness of X-ray synchrotron radiation systems for real time observations, mouse fetal skeleton development was monitored with a high resolution X-ray synchrotron. A non-monochromatized X-ray synchrotron (white beam, 5C1 beamline) was employed to observe the skeleton of mice under anesthesia at embryonic day (E)12, E14, E15, and E18. At the same time, conventional radiography and mammography were used to compare with X-ray synchrotron. After synchrotron radiation, each mouse was sacrificed and stained with Alizarin red S and Alcian blue to observe bony structures. Synchrotron radiation enabled us to view the mouse fetal skeleton beginning at gestation. Synchrotron radiation systems facilitate real time observations of the fetal skeleton with greater accuracy and magnification compared to mammography and conventional radiography. Our results show that X-ray synchrotron systems can be used to observe the fine structures of internal organs at high magnification.
Animals ; Bone and Bones/*anatomy & histology/radiography ; Female ; Fetus/*anatomy & histology/radiography ; Histocytochemistry ; Mice ; Mice, Inbred ICR ; Pregnancy ; Synchrotrons ; X-Rays

This study analyzes the role of the Sorting Hat in structuring the identity of the characters in the Harry Potter series written by J. K. Rowling. In the different stages of adolescence, one explores and re-establishes one's identity. One's sense of identity is determined by the commitments made regarding personal and social traits. However, it is difficult to establish a concrete identity formation process theory that is communicable to adolescents. In Harry Potter, the characters' identities are reflected upon the Sorting Hat and are continuously molded throughout the book. The Sorting Hat provides nurturing experiences based on temperament. Based primarily on their temperament, it sorts the students into four houses, each with their own distinct characteristics. Once sorted, the houses become the living and learning communities in which the students share the same dormitory and classes until their graduation. Within the community, the students seek connections, supportive relationships, and understanding within the group. The taking on of the group identity is an explanatory variable in the formation of individual identity. The Sorting Hat provides the students with stability and a safe boundary. After being sorted based on their temperament, the inexperienced and immature adolescents can explore different options under the guidance of the Hat before making a definite commitment. By presenting them with an appropriate environment (such as a mentor, friend, or family member), the Hat further shapes their identity and integrates the identity elements ascribed in the beginning. By providing experiences and interactions based on their unique temperament and environment, the Sorting Hat plays a crucial role in establishing the students' identities. The Sorting Hat can be an ideal model for finding one's identity during adolescence.
Adolescent* ; Friends ; Fungi ; Humans ; Learning ; Mentors ; Sociological Factors ; Temperament

Runx2 and Osterix, the transcription factors for osteoblast differentiation, are known as fundamental factors to regulate the development of calcified tissues. However, the biological functions of these factors in the development of the periodontal tissues remain unclear. In this study, we investigated the distribution of Runx2 and Osterix during periodontal tissue development of the mice. Mandibles from 14-day-old mice were prepared for paraffin section. Serial sections of the mandible containing 1st molar tooth germs were obtained as a thickness of 7 microm. Some sections were stained with hematoxylin and eosin. Others were used for immunohistochemistry for PCNA, Runx2, and Osterix. Epithelial cells in growing end of Hertwig's epithelial root sheath (HERS) and mesenchymal cells adjacent to the growing end of HERS expressed PCNA. Undifferentiated mesenchymal cells and hard tissue forming cells like cementoblasts and osteoblasts in early stage of differentiation expressed Runx2. Fully differentiated cementoblasts and osteoblasts secreting matrix proteins expressed Osterix. However, the cells terminated the matrix formation did not express Osterix. Periodontal ligament cells expressed Runx2 and Osterix. Pulp cells expressed Runx2 only.These results suggest that Runx2 and Osterix might regulate the differentiation of cementoblasts in the same manner as osteoblasts. Runx2 might participate in the process of cementoblast differentiation in early stage, whether Osterix might regulate the maturation and matrix synthesis of the cells.
Animals ; Dental Cementum ; Eosine Yellowish-(YS) ; Epithelial Cells ; Hematoxylin ; Immunohistochemistry ; Mandible ; Mice ; Molar ; Osteoblasts ; Paraffin ; Periodontal Ligament ; Proliferating Cell Nuclear Antigen ; Proteins ; Tooth Germ ; Transcription Factors

OBJECTIVES: Echocardiographically determined left ventricular hypertrophy is associated with increased risk for sudden cardiae death and for complex ventricular arrhythmias in 24-hour ambulatory electrocardiographic monitoring. In subjects with left ventricular hypertrophy, the presence of asymptomatic complex ventricular arrhythmias is associated with higher incidence of sudden cardiac death and higher cardiovascular mortality. However, their accurate relationship and prognostic significances have been remained to be established. The purpose of this study was to evaluate the relationship between complex ventricular arrhythmias, left ventricular hypertrophy, and sudden cardiac death in Korean patients. METHODS: Twenty four hour ambulatory electrocardiographic monitoring, echocardiographic data and medical records were reviewed in 360 subjects from 1991 to 1994. We evaluated the relationship between complex ventricular arrhythmias and left ventricular mass index, and the prognostic values of them. Of the 360 subjects, 187 could be followed up for one to four years. The mean follow-up period was 2.8 years. RESULTS: The incidence of complex ventricular arrhythmias was significantly correlated with left ventricular mass index and ejection fraction in all subjects. During the follow-up periods, seven of 187 subjects died from sudden cardiac death. Six of them had complex ventricular arrhythmias with left ventricular hypertrophy. CONCLUSION: The incidence of complex ventricular arrhythmias was significantly correlated with echocardiographically determined left ventricular hypertrophy and it is suggested that subjects with complex ventricular arrhythmias combined with left ventricular hypertrophy have higher risk for sudden cardiac death.
Arrhythmias, Cardiac* ; Cardia ; Death, Sudden, Cardiac ; Echocardiography ; Electrocardiography, Ambulatory ; Follow-Up Studies ; Humans ; Hypertrophy, Left Ventricular* ; Incidence ; Medical Records ; Mortality ; Prognosis