No abstract available.
Alloys* ; Joints*

No abstract available.
Prostatectomy* ; Prostatic Intraepithelial Neoplasia*

No abstract available.
Prostatectomy* ; Prostatic Intraepithelial Neoplasia*

BACKGROUND: Prostaglandin system is known to participate in manifestation of the renin-angiotensin system. However, role of prostaglandins on the renin-angiotensin system in development of hypertension is not well established. This study was to examine whether the role of prostaglandins is altered in experimental hypertension. METHODS: Two-kidney, one-clip(2KIC) renal hypertension was made by clipping the left renal artery with a silver clip(internal gap of 0.2mm) and deoxycorticosterone acetate (DOCA)-salt hypertension by subcutaneous implantation of DOCA(200mg/kg) strip plus saline(1%) drinking. They were used 3 weeks later. Age-matched normal rats served as a control. Femoral artery was cannulated and arterial blood pressure and heart rate were monitored continuously. RESULTS: 1) In normotensive rats, saralasin infusion(20 microg/kg/min, IV) caused a decrease in mean arterial pressure without significant alterations in heart rate. Indomethacin-pretreatment(10mg/kg, IP) abolished the depressor response to saralasin. 2) The depressor response to saralasin was more marked in renal hypertensive rats than in normotensive rats. The magnitude of maximum decrease in blood pressure, however, was comparable between the hypertensive and normotensive rats. Indomethacin-pretreatment did not affect the depressor response to saralasin in renal hypertensive rats. 3) In DOCA-salt hypertensive rats, saralasin infusion rather caused an increase in mean arterial pressure without significant alterations in heart rate. The pressor response to saralasin was not affected by indomethacin-pretreatment. CONCLUSION: These results indicate that prostaglandin system may modify renin-angiotensin system in normotensive rats. It is suggested that mechanisms other than prostaglandin system participate in the full-blown manifestation of renin-angiotensin system in 2KIC renal hypertensive rats.
Animals ; Arterial Pressure ; Blood Pressure ; Desoxycorticosterone ; Drinking ; Femoral Artery ; Heart Rate ; Hypertension ; Hypertension, Renal ; Prostaglandins I ; Prostaglandins* ; Rats* ; Renal Artery ; Renin-Angiotensin System* ; Saralasin ; Silver

Central retinal artery occlusion occurs rarely as a complication of spine surgery under general anesthesia in prone position, but is quite tragic. The suggested causes are hypotension during anesthesia and increased external ocular pressure by headrest, sand bag or others. We experienced a case of left central retinal artery occlusion following cervical spine surgery under general anesthesia using a horseshoe headrest. The patient was 53 years old male whose medical history was non remarkable except dislocation of cervical spine. He was positioned prone after induction. The vital signs were stable during opreration. At the recovery room, he presented left visual field disturbance and investigations revealed that left central retinal artery occlusion occured. This case demonstrates that proper positioning of the head on an adequate head rest and contineous cautious inspection during surgical procedure are important to prevent retinal damage.
Anesthesia ; Anesthesia, General* ; Dislocations ; Head ; Humans ; Hypotension ; Male ; Middle Aged ; Prone Position* ; Recovery Room ; Retinal Artery Occlusion* ; Retinal Artery* ; Retinaldehyde ; Silicon Dioxide ; Spine* ; Visual Fields ; Vital Signs

Porphyromonas gingivalis is strongly implicated in the pathogenesis of adult periodontitis, the major cause of tooth loss in adults. Use of an antibacterial agent controlling P. gingivalis as a periodontal therapeutic agent has been rationalized. The present study was performed to observe the antibacterial effect of inorganic polyphosphates (polyP) on P. gingivalis. P. gingivalis 2561 was grown in half-strength brain-heart infusion broth containing hemin and vitamin K with or without polyP. Minimal inhibitory concentration (MIC) of polyP with various chain lengths was determined by measuring the absorbance of the grown cells at 540 nm. MIC of polyP for the bacterium was determined to be 0.05%. The effect of polyP with a chain length of 75 (polyP 75) was further examined. PolyP 75 added to the growing culture of P. gingivalis at its exponential phase was as effective in inhibiting the growth of P. gingivalis as polyP 75 added at the very beginning of the culture. More than 99% of the cells lost their viability determined by viable cell count when polyP 75 was added to the culture of growing P. gingivalis at the concentration of 0.06%, suggesting that polyP 75 has a bactericidal effect on the bacterium. Intracellular nucleotide release from the cells was increased by approx. 20% in the presence of polyP 75 but was not reversed by the addition of divalent cations like Ca++ and Mg++. Under the transmission electron microscope, only a small number of the growing P. gingivalis cells were actually lysed. However, the majority of the cells appeared to be atypical in their shape, demonstrating accumulation of highly electron-dense granules and bodies of condensed nucleic acid-like material in the cytoplasm. In the presence of polyP 75, the protein profile of P. gingivalis was changed as determined by SDS-polyacrylamide gel electrophoresis and immunoblot, and the proteolytic activity of the bacterium demostrated on the zymograms was decreased. The overall results suggest that polyP have a strong bactericidal activity against P. gingivalis in which lysis in relation to chelation may not play the major role but unknown mechanism that possibly affects the viability of the bacterium may be involved. PolyP may be used as an agent for prevention and treatment of periodontitis.
Adult ; Cations, Divalent ; Cell Count ; Chronic Periodontitis ; Cytoplasm ; Electrophoresis ; Hemin ; Humans ; Periodontitis ; Polyphosphates* ; Polyps ; Porphyromonas gingivalis* ; Porphyromonas* ; Tooth Loss ; Vitamin K

Although many studies show that thromboxane A2 (TXA2) has the action of gastrointestinal (GI) motility using GI muscle cells and tissue, there are no reports on the effects of TXA2 on interstitial cells of Cajal (ICC) that function as pacemaker cells in GI tract. So, we studied the modulation of pacemaker activities by TXA2 in ICC with whole cell patch-clamp technique. Externally applied TXA2 (5 micrometer) produced membrane depolarization in current-clamp mode and increased tonic inward pacemaker currents in voltage-clamp mode. The tonic inward currents by TXA2 were inhibited by intracellular application of GDP-beta-S. The pretreatment of ICC with Ca2+ free solution and thapsigargin, a Ca2+-ATPase inhibitor in endoplasmic reticulum, abolished the generation of pacemaker currents and suppressed the TXA2-induced tonic inward currents. However, chelerythrine or calphostin C, protein kinase C inhibitors, did not block the TXA2-induced effects on pacemaker currents. These results suggest that TXA2 can regulate intestinal motility through the modulation of ICC pacemaker activities. This modulation of pacemaker activities by TXA2 may occur by the activation of G protein and PKC independent pathway via extra and intracellular Ca2+ modulation.
Animals ; Benzophenanthridines ; Endoplasmic Reticulum ; Gastrointestinal Motility ; Gastrointestinal Tract ; GTP-Binding Proteins ; Guanosine Diphosphate ; Interstitial Cells of Cajal ; Intestines ; Membranes ; Mice ; Muscle Cells ; Naphthalenes ; Patch-Clamp Techniques ; Protein Kinase C ; Thapsigargin ; Thionucleotides ; Thromboxane A2

The indole alkaloid harmaline has been to cause tremor and ataxia, and produce cerebellar neurotoxicity in rat. Degeneration of Purkinje cell alligned in narrow parasagittal bands result from excitation of inferior olivary nucleus in harmaline-treated rats. The objective of this study was to investigate the hypothesis that excitation of climbing fiberinduced by harmaline mediates Purkinje cell injury or degeneration. For this purpose, the inferior olive of rats was chemically ablated by using 3-acetyl pyridine, a neurotoxic chemical, and cerebellar damage followed by administration of harmaline was analyzed using immunohistochemical markers for neurons, glial cells. The results demonstrated that a subset of Purkinje cell in the vermis and paravermis degenerated after harmaline treatment, but harmaline produced little or no Purkinje cell degeneration after inferior olivary ablation. These results suggested that harmalineinduced activation of inferior olivary neurons may lead to release of glutamate from climbing fiber synaptic terminal distributed over the Purkinje cells, and may lead to cytotoxic degeneration of Purkinje cells.
Animals ; Ataxia ; Cerebellum ; Glutamic Acid ; Harmaline* ; Neuroglia ; Neurons ; Olea ; Olivary Nucleus ; Presynaptic Terminals ; Purkinje Cells* ; Rats ; Tremor

PURPOSE: To determine the MR imaging findings of spinal cord decompression sickness. MATERIALS AND METHODS: We retrospectively analysed the spinal MR images of eight patients (M : 6, F : 2) with decompression sickness affecting the cervical spine (n=1) or thoracic spine (n=7). The observed extent, location, continuity, signal intensity and contrast enhancement pattern of spinal cord lesions were analysed. RESULTS: The chief MR finding was continuous (n=2) or non-continuous (n=3) high signal intensity on T2-weighted images in the posterior paramedian spinal cord. In three cases, additional T2 signal abnormality in the ventral horn of the gray matter was observed. There was no signal intensity abnormality on T1- weighted images or abnormal enhancement on post-Gadolinium T1-weighted images. In one case, cord swelling in addition to T2 signal abnormality was observed. CONCLUSION: MR imaging is useful for evaluating spinal cord lesions in patients with decompression sickness.
Animals ; Decompression Sickness* ; Decompression* ; Horns ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies ; Spinal Cord* ; Spine

BACKGROUND: An increase of the extracellular K+concentrations up to about 8 mM in the isolated vessels causes relaxation in pre-contracted state. In order to elucidate the mechanisms of K+induced relaxation and compare with that of 2-kidney, 1 clip (2K1C) renal hypertensive rats, we recorded aortic vascular tension using an organ bath study. METHOD: 2K1C hypertension was made by clipping the left renal artery and age-matched control rats received a sham treatment. Thoracic aortic rings were mounted in tissue baths for measurement of isometric contractile force. RESULTS: Exposure to K+(from 2 to 8 mM) relaxed a phenylephrine (2 x 10-6 M)-induced contraction in K+free Krebs-Ringer solution, dose-dependently. Ouabain (10-5 M) enhanced the K+induced relaxation in above 2 mM K+ The K+induced relaxation was still induced in endothelium-denuded condition. Incubation with the K+channel blockers such as tetraethylammonium (TEA, 1 mM), glibenclamide (10-5 M), 4-aminopyridine (3 mM), barium (5 mM) and cesium (2 mM) did not affect on the K+induced relaxation. In renal hypertensive rats, the K+induced relaxation was markedly suppressed and ouabain enhanced it. CONCLUSIONS: These results suggest that the K+induced relaxation in aorta be mediated by Na-pump independent mechanisms, and the decrease of the K+induced relaxation in the renal hypertensive rats may be a possible mechanism of hypertension.
4-Aminopyridine ; Animals ; Aorta ; Barium ; Baths ; Cesium ; Glyburide ; Hypertension ; Muscle, Smooth* ; Ouabain ; Phenylephrine ; Placebos ; Rats* ; Relaxation ; Renal Artery ; Tetraethylammonium ; Vasodilation*