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991.
To investigate the relationship between plasma levels and coronary vasodilation after administration of isosorbide dinitrate (ISDN), the plasma concentration and diarneters of six segments of the left coronary artery were measured before and after sublingual (SL) ISDN (5 mg) and left intracoronary (IC) administration of ISDN (3 mg) in 12 patients. After SL-ISDN, the systolic aortic pressure decreased with no significant concomitant changes in heart rate or diastolic aortic pressure. After IC-ISDN, all hemodynamic parameters showed significant changes, and these were greater after IC-ISDN than those after SL-ISDN. The individual mean vasodilation of six segments induced by SL- and IC-ISDN, were 23± 9 and 35± 11% (p<0.01), respectively. Before SL-ISDN, ISDN was not detected in plasma. After SL- and IC-ISDN, however, the plasma values of the ISDN were 36.1± 53.3 and 101.5± 90.0 ng/ml (p<0.01), respectively. Thus, both coronary vasodilative responses and plasma ISDN levels after IC-ISDN were significantly greater than those after SL-ISDN. However, neither the individual mean coronary vasodilation nor the hemodynamic changes correlated significantly with plasma ISDN levels. Consequently, with administration of the same dose, the coronary vasodilative response to ISDN did not correlate with plasma levels. Furthermore, IC-ISDN dilates coronary arteries more effectively than SL-ISDN.  相似文献   
992.
A 54-year-old Japanese woman was diagnosed with rheumatoid arthritis (RA) in 1995 on the basis of symmetric effusive polyarthritis, morning stiffness, and strongly positive rheumatoid factor. She had received low-dose prednisolone, indomethacin, methotrexate (MTX), and cyclophosphamide (CPA), at least, over 4 years before the current admission and showed partial improvement of polyarthralgia. In November 2002, she suddenly developed thrombocytopenia (platelet count was 0.3×104 mm–3) with purpura and was diagnosed with immune thrombocytopenic purpura (ITP). As she had refractory ITP, the administration of pulsed high-dose dexamethasone (DEX) therapy was started, resulting in the complete remission of ITP. The present paper reports that pulsed high-dose DEX therapy was useful for the treatment of refractory ITP associated with RA.  相似文献   
993.

Background

Most of the patients develop food allergy early in life. The factors related to parental immune condition might be one of the conceivable causes.

Methods

We reported murine models of food allergy and oral OVA tolerance. To investigate the influence of parental immune condition on infant food allergy, female and male mice with food allergy or oral tolerance were mated with each other.

Results

Food allergy was suppressed by decreased IgE production in the offspring of mice with food allergy. On the contrary, anaphylaxis for OVA was induced in the offspring of mice with oral tolerance. The suppression of food allergy being dependent on a maternal factor was revealed in the offspring after cross-mating mice with food allergy and oral tolerance. Because OVA-specific IgG, presumed to be from the allergic mother, was detected in the serum of naïve infants from mothers allergic to food, we assumed that the suppression was dependent on a specific IgG. The serum IgG purified by a G-protein column was administered before OVA sensitization in the food allergy model, and OVA-specific IgE production was found to be diminished in the administered mice. However, OVA-specific monoclonal IgG1 and IgG2a administration could not suppress food allergy. Because we detected OVA-IgG immune complex in the serum of mothers allergic to food, it might be a cause of maternal immune suppression.

Conclusions

We demonstrated that maternal specific IgG conjugated food antigen is an important factor related to the development of food allergy and acquiring tolerance.  相似文献   
994.
A 34-year-old man who had a history of ulcerative colitis (UC) was admitted to our hospital with complaints of arthralgia, erythema nodosum, recurrent oral aphthous ulcers and bloody stools. A colonoscopy revealed multiple aphthous ulcers on his cecum and colon and also revealed a transmural ulcer on his rectum consistent with a diagnosis of UC. The patient was HLA-B51 positive. Based on clinical evidence [recurrent oral ulcers, skin lesions (erythema nodosum), positivity for pathergy test] this patient was diagnosed as having Beh?et's disease with gastrointestinal involvement. We describe this rare case of Beh?et's disease with colitis and discuss the difficulties in making a differential diagnosis between Beh?et's disease and the inflammatory bowel diseases.  相似文献   
995.
Inactivation of the tumor suppressor p53 by missense mutations is the most frequent genetic alteration in human cancers. The common missense mutations in the TP53 gene disrupt the ability of p53 to bind to DNA and consequently to transactivate downstream genes. However, it is still not fully understood how a large number of the remaining mutations affect p53 structure and function. Here, we used a comprehensive site-directed mutagenesis technique and a yeast-based functional assay to construct, express, and evaluate 2,314 p53 mutants representing all possible amino acid substitutions caused by a point mutation throughout the protein (5.9 substitutions per residue), and correlated p53 function with structure- and tumor-derived mutations. This high-resolution mutation analysis allows evaluation of previous predictions and hypotheses through interrelation of function, structure and mutation.  相似文献   
996.
Inflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha) have been implicated in atherogenesis. However, the precise role of TNF-alpha in atherogenesis is still unclear. To examine the effect of TNF-alpha on atherogenesis, we generated compound-deficient mice in apolipoprotein E (apoE) and TNF-alpha (apoE-/-/TNF-alpha-/-) and compared them with apoE-/- mice. Although serum total cholesterol levels were markedly elevated in both apoE-/-/TNF-alpha-/- and apoE-/- mice compared to wild-type mice, no differences were observed between apoE-/-/TNF-alpha-/- and apoE-/- mice. The atherosclerotic plaque area in the aortic luminal surface of apoE-/-/TNF-alpha-/- mice (n=8, 3.1+/-0.4%) was significantly smaller than that of apoE-/- mice (n=7, 4.7+/-0.4%, p<0.001) despite the lack of difference in serum cholesterol levels. The atherosclerotic lesion size in the aortic sinus of apoE-/-/TNF-alpha-/- mice (n=10, 5.1+/-0.3 x 10(5)microm(2)) was also significantly smaller than that of apoE-/- mice (n=11, 7.0+/-0.3 x 10(5)microm(2), p<0.0001). RT-PCR analysis indicated that the expression levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) were significantly higher in apoE-/- than apoE-/-/TNF-alpha-/- mice. Macrophages from apoE(-/-) mice showed higher uptake level of oxidized LDL and increased expression level of scavenger receptor class A (SRA) compared to those from apoE-/-/TNF-alpha-/- mice. These results indicate that TNF-alpha plays an atherogenic role by upregulating the expressions of ICAM-1, VCAM-1 and MCP-1 in the vascular wall, and by inducing SRA expression and oxidized LDL uptake in macrophages.  相似文献   
997.
Polymorphonuclear leukocytes (PMNs) mediate antibody-dependent cellular cytotoxicity (ADCC), which is increased by the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF). We sought to determine whether PMN ADCC also would be increased by the addition of an antibody/GM-CSF fusion protein and whether this would be associated with the up-regulation and activation of Mac-1 (CD11b/CD18) and with azurophil granule exocytosis. ADCC against LA-N-1 human neuroblastoma cells was evaluated with 4-hour calcein acetoxymethyl ester (calcein-AM) microcytotoxicity assay, electron microscopy, and multi-parameter flow cytometry. With the calcein-AM assay, LA-N-1 cell survival was 10%, 55%, and 75% when PMN ADCC was mediated by the antidisialoganglioside (anti-GD2) immunocytokine hu14.18/GM-CSF, by monoclonal antibody (mAb) hu14.18 mixed with GM-CSF, and by hu14.18 alone. Function-blocking mAbs demonstrated that FcgammaRII and FcgammaRIII were required for ADCC with hu14.18 alone or mixed with GM-CSF, but that only FcgammaRII was required for ADCC with hu14.18/GM-CSF. ADCC mediated by hu14.18 and hu14.18/GM-CSF was Mac-1 dependent. Electron microscopy demonstrated the greatest PMN adhesion, spreading, and lysis of targets with hu14.18/GM-CSF. Monoclonal antibodies blocking Mac-1 function allowed the tethering of PMN to targets with hu14.18/GM-CSF but prevented adhesion, spreading, and cytolysis. Flow cytometry showed that hu14.18 with or without GM-CSF and hu14.18/GM-CSF all mediated Mac-1-dependent PMN-target cell conjugate formation but that GM-CSF was required for the highest expression and activation of Mac-1, as evidenced by the mAb24-defined beta(2)-integrin activation epitope. Hu14.18/GM-CSF induced the highest sustained azurophil granule exocytosis, almost exclusively in PMNs with activated Mac-1. Thus, hu14.18/GM-CSF facilitates PMN ADCC against neuroblastoma cells associated with FcgammaRII and Mac-1-dependent enhanced adhesion and degranulation.  相似文献   
998.
Aim: This study was designed to investigate the effects of 24‐month long‐term transdermal hormone replacement therapy (HRT) on the circulating levels of components of the renin–angiotensin–aldosterone system (RAAS) and bradykinin, blood pressure (BP) and lipid profile in normotensive postmenopausal women (PMW). Methods: Twenty‐two normotensive PMW were randomized to receive transdermal HRT (continuous 17‐β estradiol patch at 36 µg/day plus cyclic oral medroxyprogesterone acetate 2.5 mg/day for 12 days/month) (n = 12) or control (n = 10). The plasma renin activity (PRA), serum angiotensin‐converting enzyme (ACE) activity, plasma angiotensin (Ang) I, Ang II, aldosterone, bradykinin, and BP were measured before, and 12 and 24 months after, the start of the HRT. Results: In the HRT group, the diastolic BP and mean BP were significantly decreased at 12 and 24 months (both P < 0.05) after the start of therapy, however, no significant change of the systolic BP was noted during the study period. No changes in the RAAS components or lipid profile were noted in either group. The plasma bradykinin levels were significantly reduced at 12 (P < 0.05) and 24 months (P < 0.01), while no changes were observed in the control group. Conclusion: More than 12 months of long‐term transdermal HRT kept diastolic BP, mean BP and plasma bradykinin levels decreased in normotensive PMW, without influencing any of the components of the RAAS. This therapy may allow optimal blood pressure control and prevent elevation of the cardiovascular risk.  相似文献   
999.
BACKGROUND: It is not fully clarified how diabetes mellitus (DM)-induced cardiac dysfunction is associated with histopathological changes of the heart in a long lasting period of DM. METHODS AND RESULTS: Eighteen weeks after a streptozotocin injection was given to Wistar - Kyoto rats (D rats), echocardiography and hemodynamic studies including the dobutamine infusion test were performed. After perfusion fixation, immunofluorescent staining and histopathology of the heart were analyzed, and analysis with electron microscopy was also conducted. Systolic blood pressure in the conscious state and left ventricular (LV) ejection fraction by 2-dimensional echocardiography were reduced in D rats. LV mechanical responses to dobutamine assessed by maximal LV pressure derivative (+LVdP/dt) also decreased with higher dobutamine doses in D rats. Although LV and right ventricular (RV) wall thickness were smaller in D rats, there were increased RV volumes, indicating LV and RV dilatational remodeling in D rats. The cardiomyocyte transverse diameter and actin staining in cardiomyocytes in both the LV and RV were significantly reduced, and capillary tortuosity and type IV collagen were increased, indicating microangiopathy in D rats. CONCLUSIONS: Advanced insulin-dependent DM incurred not only RV remodeling but also overt resting LV systolic dysfunction and decreased LV responsiveness to beta adrenergic stimulation with dilatational remodeling, accompanied by pathological changes of capillaries and cardiomyocytes including actin filaments.  相似文献   
1000.
Gastric cancer, the leading cause of death from cancer in Japan, has long been studied. We received our first patient with early gastric cancer in 1950 and have since treated 2382 patients with this cancer up to 1990. The percentage of early gastric cancers diagnosed has been on the increase following the improvement in diagnostic skills and the establishment of mass screening. At present, more than half of the gastric cancers presenting are in the early stages. Chronological changes in diagnoses of early gastric cancer are characterized by the increased findings of (a) small tumors less than 4 cm in diameter (b) depressed-type carcinoma (c) lesions of the upper part of the stomach, and (d) undifferentiated-type adenocarcinoma. The standard method of treatment for early gastric cancer was standard radical operation in the 1970s. In the 1980s endoscopic mucosal resection and limited operation were adopted and their use has been increasing annually. The prognosis for early gastric cancer is quite favorable (the 5-year survival rate is more than 90%), and it is regarded as a disease with good prognosis. To obtain still better therapeutic results, it is essential to increase the proportion of early gastric cancers where endoscopic mucosal resection or limited operation is indicated, and improve the techniques of those procedures.  相似文献   
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