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91.
Abstract Substance P is a neuropeptide which is present in peripheral C nerve endings and released from them. Free nerve endings of C nerve are present in human epidermis. The effects of substance P on the transmembrane signaling system of pig epidermal sheets were previously reported. In these studies, a small amount of cells other than keratinocytes contaminated the epidermal sheets and the species difference from human was also noticed. Therefore we investigated the effects of substance P on cultured normal human epidermal keratinocytes. Alteration of intracellular free calcium (Ca2+) in single living keratinocytes was studied using an inverted fluorescence microscope and Ca2+ -sensitive dye, Fura 2-AM. Treatment of normal human epidermal kertinocytes with substance P resulted in an increase in inositol 1,4,5-trisphosphate and in intracellular Ca2+. Substance P inhibited DNA synthesis of the keratinocytes in a dose-dependent manner. These results are consistent with the view that substance P stimulates phosphatidylinositol-4,5-bisphosphate hydrolysis of human keratinocytes, resulting in inositol 1,4,5-trisphosphate-Ca2+ signal.  相似文献   
92.
We have experienced a coagulation factor VIII-deficient patient whose plasma has normal protein S (PS) activity and masses of free PS and its bound form in complex with C4b-binding protein (C4BP). Although the patient's plasma showed a normal ratio of free PS to PS-C4BP complex in the presence of 5 mM EDTA, the plasma gave an abnormally retarding major C4BP peak together with a major PS peak in the crossed immunoelectrophoresis (CIE) in the presence of 2 mM CaCl2. It was revealed that the major peak was formed by a mixture of PS-C4BP complex and free form. The addition of normal human plasma (NHP) to the patient's plasma inhibited the retardation of the major PS-C4BP complex. These suggest that the patient's plasma lacks some component(s) to inhibit Ca2+-dependent association of PS with C4BP.  相似文献   
93.
Background: The aim of this study was to investigate the effects of two imidazoline-derived intravenous anesthetics, etomidate and midazolam, on vascular adenosine triphosphate-sensitive potassium (KATP) channel activity.

Methods: In isolated rat aorta, isometric tension was recorded to examine the anesthetic effects on vasodilator response to levcromakalim, a selective KATP channel opener. Using the patch clamp method, the anesthetic effects were also examined on the currents through (1) native vascular KATP channels, (2) recombinant KATP channels with different combinations of various types of inwardly rectifying potassium channel (Kir6.0 family: Kir6.1, 6.2) and sulfonylurea receptor (SUR1, 2A, 2B) subunits, (3) SUR-deficient channels derived from a truncated isoform of Kir6.2 subunit (Kir6.2[DELTA]C36 channels), and (4) mutant Kir6.2[DELTA]C36 channels with reduced sensitivity to adenosine triphosphate (Kir6.2[DELTA]C36-K185Q channels).

Results: Etomidate (>= 10-6 m), but not midazolam (up to 10-6 m), inhibited the levcromakalim-induced vasodilation, which was sensitive to glibenclamide (IC50: 7.21 x 10-8 m; maximum inhibitory concentration: 1.22 x 10-4 m). Etomidate (>= 3 x 10-6 m), but not midazolam (up to 10-4 m), inhibited the native KATP channel activity in both cell-attached and inside-out configurations with IC50 values of 1.68 x 10-5 m and 1.52 x 10-5 m, respectively. Etomidate (10-5 m) also inhibited the activity of various types of recombinant SUR/Kir6.0KATP channels, Kir6.2[DELTA]C36 channels, and Kir6.2[DELTA]C36-K185Q channels with equivalent potency.  相似文献   

94.
Obesity is a risk factor for cardiovascular disease and thromboembolic events. We investigated the effects of weight reduction by a 12-week calorie-restricted diet with or without aerobic exercise (diet group and diet plus exercise group) on leptin and anticoagulation proteins levels. Forty-two obese nondiabetic individuals were evaluated for blood levels of leptin, protein C activity, free protein S antigen and for body fat area calculated on computerized tomography before and after intervention. Before intervention, serum levels of leptin and free protein S antigen correlated positively with several adiposity-related parameters. After the program, body weight and fat area were significantly decreased in both groups. Body mass index and leptin levels decreased in both groups, with a larger change in the diet plus exercise group than in the diet group. Although protein C activity levels did not change in both groups, free protein S antigen levels decreased significantly in the diet plus exercise group. In conclusion, the 12-week programs had significant effects on the initial weight reduction and body fat mass, decreasing lepin levels in obese nondiabetic individuals. To clarify whether aerobic exercise has additional or direct effects on the anticoagulation system, a study in a large number of individuals is needed.  相似文献   
95.
96.
Aim:  This study aims to establish a pressure ulcers model that visualizes the microcirculation, and to examine the participation of ischemia‐reperfusion injury in the pathophysiology of pressure ulcers.
Methods:  An original system composed of a new skinfold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia‐reperfusion injury, animals were divided into two groups: the compression‐release group in which the animals received four cycles of compression‐release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day1 (35 hours) after the first evaluation.
Results and Conclusions:  The cyclic compression‐release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia‐reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. The finding supports the significant contribution of ischemia‐reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation.  相似文献   
97.
Patients with unilateral posterior crossbite often show reverse sequential jaw movement patterns on the frontal view during mastication on the crossbite side. Recent studies show that such patients are prone to suffer from temporomandibular joint (TMJ) disc displacement, particularly the lateral portion. The purpose of this study was to examine the movement of the lateral and medial poles of the working condyle during mastication in such patients. Subjects were 12 consecutive patients with unilateral posterior crossbites and without TMJ disc displacements and 12 normal subjects. An optoelectronic jaw-tracking system with 6 degrees of freedom was used to record the motion of the lateral and medial poles of the working condyle during mastication of standardized hard, gummy jelly. The data from the first 10 cycles were analyzed. The lateral and medial poles of the condyle on the crossbite side moved more in the medial direction and less in the lateral direction during mastication in the crossbite patients than the condyle in the normal subjects. The lateral pole of the working condyle moved more in the posterior and inferior directions and less in the anterior direction than the medial pole in all subjects. These results suggest that these condylar movements in patients with unilateral posterior crossbites might be related to the susceptibility to TMJ disc displacement, particularly the lateral portion.  相似文献   
98.
A 17-year-old boy with high fever, headache, and neck stiffness was admitted to our hospital. Spinal fluid showed a protein level of 215 mg/dL with myelin basic protein (579 pg/mL), 347/ microl cells (330 mononuclear cells), and a glucose level of 53 mg/dL. One week later, urinary retention, flaccid paraplegia, and sensory disturbance below the 10th thoracic level developed. MRI of the spinal cord revealed swelling and T2-high intensity area in the cord at the 11th and 12th thoracic level. Although high-dose of methylprednisolone was administered, consciousness disturbance and respiratory failure that required mechanical ventilation occurred. Bilateral abducens nerve palsy, nystagmus, and flaccid tetraparesis also occurred. Brain MRI revealed T2-high intensity area in the midbrain and pons. Nerve conduction study showed diminished amplitudes and prolonged latencies or absence of F waves. The patient was administered a combination of intravenous immunoglobulin and a high-dose of methylprednisolone. He showed improvement within one week after the treatment. Two weeks later, he recovered from respiratory failure and weakness of the upper limbs. He remained paraplegic, but gradually improved and was able to walk with support one and a half years later. We suggest the combination therapy of intravenous immunoglobulin and a high-dose of methylprednisolone is effective for patients with combined ADEM and peripheral neuropathy.  相似文献   
99.
A 56-year-old female with congestive heart failure was transferred to our institution. Aortography demonstrated aortic valve stenosis (AS) with a congenitally bicuspid valve and dilatation of the ascending aorta. Preoperative coronary angiography showed a left single coronary artery. Replacement of the aortic valve and ascending aorta was performed. She had an uneventful postoperative course. We report the case of aortic bicuspid valve stenosis with single coronary artery as an extremely rare congenital cardiac anomaly combination.  相似文献   
100.
We presented here two patients with hemorrhagic infarction occurred during subacute phase of brain embolism. The patients were 71-year-old and 73-year-old men who suffered from brain infarction of the left posterior cerebral artery and right middle cerebral artery territory, respectively. Both of them were diagnosed as having cryptogenic stroke and patent foramen ovale. After transferred to rehabilitation hospitals taking aspirin for a secondary prevention of stroke, they developed hemorrhagic infarction at day 17 and day 19, respectively. Their blood pressure remained within normal range throughout acute and subacute phase. Although most of hemorrhagic infarction occurs within 24 hours of stroke onset, some patients develop symptomatic hemorrhagic infarction even after 10 days. We need to be careful about late-onset hemorrhagic infarction, because many patients are now transferred early to rehabilitation hospitals to facilitate dedicated systematic rehabilitation.  相似文献   
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