The mechanism of forward blood flow during closed chest cardiac massage remains controversial. Two theories have been suggested: the cardiac pump theory and the thoracic pump theory. Case report is presented to illustrate the use of transesophageal echocardiography during cardiopulmonary resuscitation. The findings included right and left ventricular compression, closure of the mitral valve during compression, opening of the mitral valve during the release phase, and atrioventricular regurgitation during compression, indicating a positive ventricular-to-atrial pressure gradient. These findings suggest that direct cardiac compression was the predominant mechanism of forward blood flow during cardiopulmonary resuscitation in this patient. Transesophageal echocardiography offers a new approach for study of the flows and cardiac morphologic features during chest compressions in humans. An understanding of the actual mechanisms involved is necessary if improved cardiopulmonary resuscitative techniques are to be rationally developed for enhancing the outcome of resuscitation.
Cardiopulmonary Resuscitation ; Echocardiography* ; Echocardiography, Transesophageal ; Heart Massage* ; Humans ; Mitral Valve ; Resuscitation ; Thorax*

Primary irritant dermatitis is one of the most common skin disease caused by various hazardous chemicals produced from the environment. For the detection of skin irritant potency, in vivo models such as human and animal patch test have been used, Keratinocyte culture method which has been set up very recently is another alternative in vivo method of detecting skin irritarlcy. LVe have investigated the effects of three skin irritants, phenol, benzoyl peroxide (BP), and sodium lauryl sulfate(SLS) on the keratinocyte culture system. Prostaglandin E(PGE) measurement, cell count and electron microscopic observation were performed after adding three irritants of different concentrations to the cultured keranocyte cells. The main results of this study were as follows : 1. There were statistically significant decreased cell number in concentration of 10 M phenol, 10 4M BP and SLS. The order of cytotoxic potency was SLS>BP >phenol. 2. In case of PGE production, decreased PGE production was observed 6 hours after addition of the irritants, except 10 M phenol and 10M BP groups. Decrea sing tendency sustained until 24 hours, however all were statistically nonsignificant comparing with control group. 3. Electron microscopic finding showed that dilatation of endoplasmic reticulums in 10 M phenol group, condensation and dilatation of mitochondrias in 10 4M BP group, and most of the cells were swollen in 10 4M SLS group. These results suggest that cell count is a useful model for performing cytotoxi city test in keratinocyte culture decreased PGE production represents cytotoxic effect in high concentration of primary irritants and ultrastructural changes may reflect the different pathomechanisms in cytotoxicity.
Animals ; Benzoyl Peroxide ; Cell Count ; Dermatitis, Irritant ; Dilatation ; Dinoprostone ; Endoplasmic Reticulum ; Hazardous Substances ; Humans* ; Irritants* ; Keratinocytes* ; Mitochondria ; Patch Tests ; Phenol ; Prostaglandins E ; Skin ; Skin Diseases ; Sodium

Incorporation of bromodeoxyuridine(BrdU) and expression of osteocalcin and transglutaminase C(TGase C) during fracture healing and distraction osteogenesis were investigated in the rat with immunohistochemical studies. Transverse osteotomy was made at the proximal tibia. Bilateral dynamic mini-fixator was applied to immobilize the fracture and also to lengthen the leg. Distraction was started, at the rate of 0.25 mm twice daily, from the 4th operative day and continued for 7 days. Animals were killed for immunohistochemical studies on the 1st, 3rd, 5th, 7th, 14th, 28th, 42nd, 56th, and 84th day after osteotomy or distraction. Longitudinal histologic sections of the healing bone were stained with monoclonal antibodies against BrdU, osteocalcin, and TGase C. Radiologically, complete fracture healing was achieved in 6 weeks after osteotomy, while neo-osteogenesis was successfully achieved in the distracted gap in 7 weeks after the completion of distraction, During active healing stage of the fracture and distraction osteogenesis, BrdU was mainly expressed in the perisoteal and endosteal osteoprogenitor cells while osteocalcin was expressed in the proliferating osteoprogenitor cells, osteoblast, osteocyte, osteoid matrix, and chondrocyte. The expression of BrdU and osteocalcin in the mesenchymal cells from the surrounding soft tissues around the osteotomy site was negligible. At the site of enchondral bone formation, TGase C was expressed in the cytomplasm of more centrally located and matured chondrocytes, while oseocalcin was mainly expressed in the cytoplasm of peripherally located chondrocyte. These findings may suggest that osteocalcin participates in early phase of enchondral bone formation, while TGase C in the late phase, suggesting the role of TGase C in matrix stabilization. At the site of intramern-branous bone formation, the expression of TGase C was weakly positive in both osteoprogenitor cell and osteoblast. The reason of the difference in the expression of TGase C between the enchondral bone formation and intrarnembranous bone formation should be further investigated. Fracture healing and distraction osteogenesis was predominantly induced by intramembranous ossification rather than enchondral ossification. Periosteal osteoprogenitor cells appeared to initiate and to lead bone formation after osteotomy and distraction. Active proliferation and differentiation of osteoprogenitor cell ocurred during entire periods of distraction. Also, active osteoid matrix formation and mineralization was started from the 5th day of distraction and continued thereafter for further 4 weeks after completion of the lengthening. These findings indicate that preservation of the periosteum is essential to achieve successful fracture healing and distraction osteogenesis.
Animals ; Antibodies, Monoclonal ; Bromodeoxyuridine ; Chondrocytes ; Cytoplasm ; Fracture Healing ; Leg ; Miners ; Osteoblasts ; Osteocalcin ; Osteocytes ; Osteogenesis ; Osteogenesis, Distraction ; Osteotomy ; Periosteum ; Rats ; Tibia

PURPOSE: Phospholipase D (PLD) catalyzes the hydrolytic cleavage of terminal phosphate diester bond of glycerophopholipids to produce phosphatidic acid (PA). PLD plays an important role in signal transduction and is known to be involved closely in cancer promotion, inflammation, and other cell responses. In order to evaluate radiation effect in tumor cells, various cells were screened for PLD activities and examined their radiation effects on PLD following gamma- ray irradiation. MATERIALS AND METHODS: PLD activities in 19 species of cell were measured by radioactive isotope method with 1,2 - di [1-14C] phosphatidylcholine in the presence of oleate. Among the cell lines examined, VERO 76, L 1210 and P 388 were selected and examined for their effects of metal ions and agonists on PLD activities before and after irradiation by Co-60 teletheraphy unit. RESULTS: The activities of oleate-PLD were observed in 11 species among 19 cell lines examined. VERO 76 and L 1210 cells showed that the PLD activity increased immediately after irradiation and reached to 150~200% of the control levels. The activation of PLD in response to gamma-ray was maximum at 20 Gy. In irradiated VERO 76, the stimulatory effect of Mg2+ was reduced and the activation of PLD by agonists in irradiated cells vary from those of the control cells. CONCLUSION: The activation effect of irradiation on PLD activity observed strongly implies that the PLD activity is closely related to the phenomena of cell necrosis. Therefore the cell lines examined here could provide a good source for the study of radiobiology that cover from cell death to cancer promotion.
Cell Death ; Cell Line* ; Inflammation ; Ions ; Necrosis ; Oleic Acid ; Phosphatidic Acids ; Phosphatidylcholines ; Phospholipase D ; Radiation Effects ; Radiobiology ; Signal Transduction

No abstract available.
Astrocytes* ; Gene Expression* ; Humans* ; Polymerase Chain Reaction*

Post-menopausal osteoporosis is known to be related to estrogen deficiency. The purpose of this experimental study is to investigate whether or not estrogen administration can prevent or retard the process of osteoporosis induced by oophorectomy in rats. Fifty-two Sprague-Dawley rats, aged five months, were separated into three groups. Group 1 (4 rats) was control group that had sham operation without oophorectomy. Goup 2 (32 rats) was another control group that had bilateral oophorectomy alone. Group 3 (16 rats) was experimental group that had estradiol administration from the fourth week through the eighth week after bilateral oophorectomy. In group 1, all the rats were killed at the fourth week after sham operation. In group 2 and group 3, four rats in each group were killed weekly until the eighth week after oophorectomy. All the animals were subjected to radiological, histological studies on the tibia, ilium, skull, and the sixth lumbar vertebra. Also, histomorphometric measurements were 1. Osteoporotic changes were evident from the fifth week after oophorectomy and increased with time on the radiologic examination in group 2. In contrast, osteoporotic changes were evident from the second week after oophorectomy and progressed with time on the histological and histomorphometric studies in group 2. 2. After administration of estradiol, osteoporotic changes which include thinning of the cortex, decrease of the amount of trabeculae were partially restored on the radiological, histological studies in group 3. 3. Histomorphometric study revealed that the trabecular area percent (the proportion of total area of the trabeculae from the whole metaphyseal area), decreased progressively through the eight week after oophorectomy in gorup 2. Whereas the trabecular area percents of group 3 were higher than those of group 2, but still lower than initial value before oophorectomy. Based on the above observations, estradiol administration appeared to delay the progression of the osteoporotic changes induced by oophorectomy in rats.
Animals ; Estradiol ; Estrogens ; Female ; Humans ; Ilium ; Osteoporosis ; Osteoporosis, Postmenopausal ; Ovariectomy ; Rats ; Rats, Sprague-Dawley ; Skull ; Spine ; Tibia

The purpose of this study was to investigate kinetics of the osteblast cell lineage in the periosteum and endosteum according to different distraction rates in callotasis of rats' Tibiae. 120 rats underwent osteotomy at the proximal metaphysio-diaphyseal junction of the left tibia for callotasis. Lengthening was started with varying distraction rates of 0.25 mm (group I), 0.5 mm (group II), 0.75 mm (group III), 1.0 mm (group IV) until 3.5 mm length gain was achieved. The animals that had osteotomy alone without lengthening served as a control(group V). Immunohistochemical staining of proliferating cell nuclear antigen(PCNA), osteocalcin and transglutaminase C(TGase C) were done on the four animals on each group sacrified at post-distraction 1, 3, 5, 7, 14, 28 days in order to observe the temporal changes among the experimental and control groups. At each examination, radiographic and histological studies were also done in order to correlate the immunohistochemical findings. The results obtained are summarized as follow; 1. The staining rate of PCNA was highest at the early distraction(day 1) phase and subsequently decreased in all groups. The staining rate of the cells in the periosteum was significantly higher than that of the cells in the endosteum (p < 0.01). 2. The expression rates of osteocalcin in the periosteum of all groups were significantly higer than those in the endosteum (p < 0.01). 3. The expression rates of TGase C in the periosteum of all groups were significantly higer than those in the endosteum (p < 0.05). 4. Radiological and histological studies revealed that successful regenerate bone healing was achieved in groups, I, II and III but not complete in group IV. In conclusion, immunohistochemical study on callotasis of rats' tibiae revealed that the osteoblast cell lineage in the periosteum is more activated than that in the endosteum for proliferation and differentiation by distraction, suggesting that the periosteum plays a more important role in neo-osteo-genesis in the distraction gap. Daily distraction rate range of 0.25 mm to 0.75 mm in two increments is the appropriate for successful distraction osteogenisis of rat's tibia, but the rate of 0.25 mm a day is significantly better than that of 0.75 mm upon immunohistochemical observation.
Animals ; Cell Lineage ; Kinetics ; Osteoblasts ; Osteocalcin ; Osteogenesis, Distraction ; Osteotomy ; Periosteum ; Proliferating Cell Nuclear Antigen ; Rats ; Tibia

No abstract available.
Ethmoid Bone* ; Meningitis, Bacterial*

PURPOSE: Functional MR imaging is the method of demonstrating changes in regional cerebral blood flow produced by sensory, motor, and any other tasks. Functional MR of visual cortex os performed as a patient stares a photic stimulation, so adaptable photic stimulation is necessary. The purpose of this study to evaluate whether the size of photic stimulation can affect the degree of visual cortex activation. MATERIALS AND METHODS: Functional MR imaging was performed in 5 volunteers with normal visual acuity. Photic stimulator was made by 39 light-emitting diodes on a plate ,operating at 8 Hz. The sizes of photic stimulator were full field, half field and focal central field. The MR imager was Siemens 1.5-T Magenton Vision system, using standard head coil. Functional MRI utilized EPI sequence (TR/TE=1.0/51. 0msec, matrix No.=98x128, slice thickness=8mm) with 3sets of 6 imaging during stimulation and 6 imaging during stimulation and 6 imaging during rest, all 36 scanning were obtained. Activated images were obtained using postprocessing software(statistical analysis by Z-zone, and these images were combined with T-1 weighted anatomical images. The activated signals were quantified by numbering the activated pixels, and activation index was obtained by dividing the pixel number of each stimulator size with the sum of the pixel number of 3 study using 3 kinds of stimulators. The correlation between the activation index and the stimulation size was analysed. RESULTS: Mean increase of signal intensities on the activation area using full field photic stimulator was about 9.6%. The activation index was greatest on full field. second on half field and smallest in focal central field in 4, The index of half field was greater than that of full field in 1. The ranges of activation index were full field 43-73%(mean 55%), half field 22-40%(mean 32%), and focal central field 5-24%(13%). CONCLUSION: The degree of visual cortex activation increases with the size of photic stimulator.
Head ; Humans ; Magnetic Resonance Imaging* ; Photic Stimulation ; Visual Acuity ; Visual Cortex* ; Volunteers

BACKGROUND: Controversy exists as to whether or not inhalation anesthetics and intravenous anesthetics impair arterial oxygenation (PaO2) during one lung ventilation (OLV). Accordingly, we examined the effect of enflurane and propofol on PaO2 and pulmonary vascular resistance (PVR) during OLV. METHODS: Forty patients, who had prolonged periods of OLV anesthesia with minimal trauma to the nonventilated lung were studied in a cross over design. Patients were randomized to four groups; Group 1 received 1 MAC of enflurane and oxygen from induction until the first 20 min after complete lung collapse, then were switched to propofol 100 g/kg/min (P100). In group 2, the order of the anesthetics was reversed. Group 3, Group 4 received the same order of the anesthetics as Group 1, Group 2, respectively but received propofol 200 g/kg/min (P200). RESULTS: During OLV, the PaO2 values were lower than those with two lung ventilation (TLV), there were no significant differences among each groups and between propofol and enflurane in PaO2, but in the selected patients (n=10, PaO2<120 mmHg during OLV), PaO2 in propofol group was higher than that of enflurane group (p<0.05). Conversion from TLV to OLV caused a significant increase in PVR, but there were no difference in PVR between propofol and enflurane group. CONCLUSIONS: These results suggest that the usual clinical dose of propofol affords no advantage over 1 MAC of enflurane anesthesia except low PaO2 patients during OLV. Propofol might be of value in risk patients of hypoxemia during thoracic surgery when OLV is planned.
Anesthesia ; Anesthetics ; Anesthetics, Inhalation ; Anesthetics, Intravenous ; Anoxia ; Cross-Over Studies ; Enflurane* ; Humans ; Lung ; One-Lung Ventilation* ; Oxygen* ; Propofol* ; Pulmonary Atelectasis ; Thoracic Surgery ; Vascular Resistance ; Ventilation