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1.
The effect of interleukin-1 on iron metabolism in rats was evaluated. Plasma iron decreased from 184 +/- 16 micrograms/dl (mean +/- SE) to 24 +/- 12 at 6 hours after interleukin-1 intramuscular administration in non-fasting rats and 109 +/- 6 micrograms/dl to 12 +/- 1 micrograms/dl in fasting rats, which was significantly lower than in control rats. Ferrokinetic studies showed a more rapid disappearance rate and lower iron turnover in interleukin-1-injected rats. The release of iron from the mononuclear phagocyte system to plasma was studied at 3 h after interleukin-1 administration. Although the percent of radioactivity in plasma of the total injected dose was 3.2 +/- 0.6% in interleukin-1, which was significantly lower than in the control rats (5.4 +/- 0.6%) at 9 h after intravenous injection of 59Fe chondroitin ferrous sulfate, there was no difference between the amount of 59Fe released from the mononuclear phagocyte system over the first 9 h in interleukin-1 and control rats. These data appear to imply that iron release is unimpaired but that, for some reason, there is an enhanced rate of clearance of the 59Fe once it has been released from the mononuclear phagocyte system into the plasma.  相似文献   
2.
The underlying mechanism involved in the interaction between neutrophil elastase inhibitors and tachykinins has not been elucidated. In this study we have examined the effects of sivelestat, a neutrophil elastase inhibitor, on the in vitro responses of airways from lipopolysaccharide (LPS)-untreated or -treated guinea-pigs to substance P. Substance P (0.01-30 micromol/l) produced concentration-dependent contractions of both tracheal and bronchial ring preparations of LPS-untreated or -treated guinea-pigs. Responsiveness to substance P in these isolated airway preparations was augmented by either epithelium removal or LPS treatment. In epithelium-intact tracheal ring preparations isolated from LPS-untreated guinea-pigs, sivelestat (100 micromol/l) significantly inhibited substance P-induced contractions. The inhibitory action was markedly attenuated by pretreatment with L-NAME (100 micromol/l) or indomethacin (2 micromol/l), and was almost undetected following removal of the epithelium. On the other hand, in bronchial ring preparations isolated from LPS-untreated guinea-pigs, sivelestat had only a very slight effect on substance P-induced contraction of the epithelium-intact preparation, whereas sivelestat greatly inhibited contraction in epithelium-removed bronchial ring preparations. In LPS-treated guinea-pigs, whether the epithelium was intact or not, sivelestat significantly inhibited the substance P-induced contraction of bronchial ring preparations. Pretreatment with L-NAME (100 micromol/l) or indomethacin (2 micromol/l) did not affect the inhibitory effect of sivelestat in bronchial ring preparations. In conclusion, epithelium removal or LPS treatment induced hyperreactivity to substance P in the guinea-pig airway. Sivelestat caused epithelium-, nitric oxide- and prostaglandin-dependent inhibition of the substance P-induced contraction of isolated guinea-pig tracheal ring preparations. In contrast, the inhibitory effect of sivelestat on substance P-induced contraction of guinea-pig bronchial ring preparations is mediated by epithelium-, nitric oxide- and prostaglandin-independent mechanisms. Sivelestat may be effective in reducing the airway hyperresponsiveness to tachykinins induced by epithelial injury as occurs in LPS-mediated inflammatory lung diseases.  相似文献   
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4.
Higher cerebral dysfunctions such as aphasia, apraxia and agnosia have seldom been reported in multiple sclerosis (MS). 12 year-old right-handed boy felt unsteadiness of the body and headache for several days. Two months later, he had the same episode and complained of visual disturbance, and weakness and sensory disturbance on the face and the extremities. Additionally, he showed amnestic aphasia, acalculia, ideomotor apraxia, finger agnosia and right-left disorientation. Cerebrospinal fluid examinations revealed increases IgG, myelin basic protein and neuron specific enolase (11%, 25 ng/ml and 28.8 ng/ml, respectively). X-ray CT scan and MRI-CT examinations revealed sclerotic lesions on the left parietal white matter and the right mid-brain. The diagnosis was made as MS. He was treated with m-PSL (methyl-prednisolone) pulse therapy for three weeks and consecutively treated with PSL for four weeks. He recovered gradually, but visual disturbance and facial palsy remained. After seven months MRI-CT showed a high signal intensity on the left parietal white matter in spite of the disappearance of the lesion on X-ray CT scan. We suggest that these higher cerebral dysfunctions may result from the lesion of the left parietal white matter which produces a disconnection between each cortical area.  相似文献   
5.
Objective: Paraplegia remains a serious complication of aortic operations. The production of free radicals during reperfusion after transient ischemia is believed to induce secondary spinal neuronal injury, resulting in paraplegia. The aim of the present study was to clarify the protective effect and method of administration of antioxidants on the neurological and histological outcome in the animal model for reperfusion injury after transient spinal cord ischemia. Methods: New Zealand white rabbits underwent surgical exposure of the abdominal aorta that was clamped for 15 minutes to achieve spinal cord ischemia. Group A animals received two 10 mg/kg doses of 3-methyl-l-phenyl-2-pyrazolin-5-one (MCI-186) at the time of release of the aortic clamp and 30 minutes later. In group B, MCI-186, 5 mg/kg, was given three times, at the time of aorta clamp release, 30 minutes and 12 hours later. In group C (control group), one dose of vehicle was administered. Neurological status was assessed using modified Tarlov’s score until 168 hours after operation. Spinal cord sections were examined microscopically to determine the extent of ischemic neuronal damage. Results: Groups A and B animals had better neurological function than group C (p(0.001). In contrast, group C animals exhibited paraplegia or paraparesis with marked neuronal necrosis. The number of surviving neurons within examined sections of the spinal cord was significantly greater in group B than in group C (p(0.001). Conclusion: In a 15-minute ischemia-reperfusion model using rabbits, systemic repetitious administration of MCI-186, a free radical scavenger, was found to have a protective effect on the spinal cord neurons both neurologically and histologically. We postulate that the drug minimizes the delayed neuronal cell death for reperfusion injury after transient ischemia by reducing the free radical molecules. Moreover, it was thought that we could protect delayed neuronal cell death more effectively by administering MCI-18612 hours later.  相似文献   
6.
Pins and wires offer the simplest and most effective tools for managing bone fractures and dislocations. Migration of these devices within the chest is rare, but can cause serious problems. The spontaneous migration of Kirschner wires from the right clavicle to the mediastinum resulted in penetrating injury of the esophagus and pseudo-aneurysm of the brachiocephalic artery in an 84-year-old patient. Two Kirschner wires were removed via a vertical incision on the right shoulder without thoracotomy and the brachiocephalic artery was replaced with a Dacron graft.  相似文献   
7.
Fluctuating PEEP (F-PEEP) is a newly developed PEEP in which end-expiratory pressure (EEP) is periodically changed within a certain range. In a dog model with unilateral lung injury induced by the introduction of hydrochloric acid, F-PEEP in which the EEP was periodically changed from 0.5 to 1.5 kPa at periods of 6 min, and conventional PEEP (C-PEEP) with an optimized EEP of 1.0 kPa, were each applied for 30 min. F-PEEP produced a significantly greater improvement of PaO2 and intrapulmonary shunt (QS/QT) than C-PEEP, and at the low EEP phase, the greatest improvement accompanied by an increased dynamic compliance and a large cardiac output was obtained. These results suggest that F-PEEP provides a useful mode of artificial ventilation for the treatment of unilateral lung injury.  相似文献   
8.
Ceruletide, a potent analogue of cholecystokinin, was administered by injection to eight schizophrenics treated with neuroleptics. We examined the dose–response effect on microvibration (MV) recorded from the chin of these patients. After 15 min of bed rest, MV was recorded for 5 min as a control recording. Subsequently, saline or ceruletide, at a dose of either 0.4 m?g/kg or at 0.8 m?g/kg, was injected according to a Latin square design with an interval of 4 weeks for washing out the drug effect and MV was recorded for 30 min. MV data obtained were subjected to the fast Fourier transform and an average power spectrum was computed. A three-way analysis of variance for these data was performed upon dose-effect, time-effect after treatment, and band-effect of the average power spectrum. The present results were similar to previous findings which had revealed effects of ceruletide on tardive dyskinesia symptoms, namely, the effects of ceruletide on MV were different according to the subjects (three cases: facilitation followed by inhibition, three cases: inhibition, two cases: no effects). The dose-response curve of ceruletide appears to be linear in some cases and an inverted U-shape in other cases. Present findings showed small doses of systemically administered ceruletide would modify muscle tonus of schizophrenics under chronic treatment of neuroleptics, and provided further reason for the therapeutic drug of tardive dyskinesia.  相似文献   
9.
For the diagnosis and evaluation of the therapy for male infertility and for predicting the outcome of AIH and IVF-ET, technically simple, replicable tests that can be performed virtually anywhere and that have definite reliability are required. The results of the HOS test correlate well with the functions of the sperm cell membrane, indicating such aspects as motility, and it is thought to be a particularly effective test of human sperm fertility. Because the HOS test reflects the functions and integrity of the sperm cell membrane, it should be possible to use it to predict the potential for fertilization of frozen sperm.  相似文献   
10.
O-beta-D-Galactopyranosyl-(1----4)-O-beta-D-galactopyranosyl-(1----4)-D- glucopyranose (designated as 4'GL) is produced from lactose by Cryptococcus laurentii. The influence of chronic ingestion of 4'GL on body weight gain, organ weight, serum lipids, and liver lipids was investigated in rats. The body weight gains of the 5% and 10% 4'GL-diet groups were higher than that of the control group. Food intake and fecal dry weight were significantly increased (p less than 0.05) by 4'GL feeding. The 4'GL diet produced a significant increase (p less than 0.01) in the wet weight and contents of both the cecum and the colon. However, no significant increase was observed in the weight of the stomach, small intestine, liver, or other organs. The effects of 4'GL on serum and liver lipid levels were not observed in this experiment. The digestion of 4'GL was measured in vitro using the artificial gastric juice, alpha-amylase of human saliva, alpha-amylase of hog pancreas, and mucosa of rat intestine. 4'GL was not hydrolyzed by these enzymes. Long-term ingestion of 4'GL did not cause any induction of 4'GL hydrolyzing enzyme activity in the rat small intestine.  相似文献   
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