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31.
We studied the effect of lymphocytosis promoting factor (LPF), derived from the supernatant fluid of a culture of phase I Bordetella pertussis strain Tohama, on human lymphocyte proliferation. LPF was a potent mitogen for human mononuclear cells, specifically T cells. LPF failed to induce cytoplasmic immunoglobulin production by B cells. Removal of the monocytes from the T cell fraction diminished responses to LPF, but the response could be restored completely by the addition of 5.0% monocytes. These results suggest that LPF-induced cell proliferation is at least partially dependent on monocytes. In contrast to PHA, LPF stimulated T gamma cells to a greater extent than non-T gamma cells, but the magnitude of the T gamma or non-T gamma cell response was less than that of T cells, indicating that synergistic interactions between T gamma and non-T gamma cells are required for maximal response.  相似文献   
32.
The effect of food deprivation for 72 h or a high fat diet on [3H]naloxone binding in the discrete brain regions of male lean Zucker rats was studied. In the midbrain, both treatments increased Bmax for the high-affinity site with no change in Kd. In the cortex, the high fat diet increased Bmax for the high-affinity site. These results suggest that dietary manipulations could produce significant changes in the endogenous opioid system.  相似文献   
33.
Claudins are integral membrane proteins at tight junctions (TJs) and form TJ strands. In the present study, we found that claudin‐7 was localized along the entire lateral membranes of epididymal epithelium, including the apical junctional region throughout the epididymis, but claudin‐8 was restricted to the apical junctional region. This finding raises the possibility that aberrant TJ strands may be formed on lateral membranes. Thus, we focused on examining whether TJ strands exist on lateral membranes of epididymal epithelium. Freeze‐fracture electron microscopy showed that aberrant TJ strands were observed in only a few principal cells in all segments of the epididymis except for the initial segment, indicating that the occurrence of aberrant strands is very rare. Aberrant TJ strands were smooth and not subdivided into individual particles in the protoplasmic face, and complementary grooves in the extracellular face were almost free of particles. Aberrant TJ strands in the distal caput and corpus epididymis were accompanied by many vesicle‐like structures but those in the proximal caput and cauda epididymis were not. These results suggest that most of claudin‐7 in lateral membranes may exist in a nonpolymerized form and may play some different roles other than the formation of TJ strands, for example, in the formation of a pool of claudin proteins or in the reinforcement of cell adhesion. Anat Rec, 1431‐1438, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
34.
Summary. In order to rapidly detect and differentiate Newcastle disease virus (NDV) isolates, a method based on real-time PCR SYBR Green I melting-curve analysis of the fusion (F) protein gene was developed. The detection limit of real-time PCR was 9 × 102 plasmid copies and was 100 times more sensitive than conventional PCR. Thirty eight reference NDV strains were rapidly identified by their distinctive melting temperatures (Tms): 89.23 ± 0.27 °C for velogenic strains, 90.17 ± 0.35 °C for pigeon mesogenic strains, 91.25 ± 0.14 °C for two lentogenic strains (B1 and Ishii). No amplification was detected from unrelated RNA samples by this method. This real-time PCR directly detected NDV from infected tissues and eliminated the gel electrophoretic step for analyzing PCR product using ethidium bromide. The total time for a PCR run was less than 1 hour. The results obtained in this study showed that the real-time PCR presented here is a good screening test for the identification of NDV.  相似文献   
35.
In our previous study, we examined reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy irradiation. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of the hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation. In the succeeding study, we examined radiation-induced ROS formation, oxidative DNA damage, early apoptotic changes, and mitochondrial membrane dysfunction in the human osteosarcoma cell line HS-Os-1. We found that ROS formation and oxidative DNA damage were actually scarcely seen after irradiation of up to 30 Gy in these cells, that mitochondrial membrane potential was preserved, and that apoptotic changes were not demonstrated despite the relatively high-dose irradiation of 30 Gy. In the present study, we examined the immunocytochemical characteristics of the apoptotic-resistance of the HS-Os-1 cell line against irradiation in order to clarify its possible implications regarding radiosensitivity. The results showed that these cells lack P53 and Bax protein expression, and strong peroxidase activity was confirmed in the nuclei of the cells. Moreover, SODII (manganese superoxide dismutase II) protein expression was gradually increased in spite of irradiation of up to 30 Gy. Therefore, it is concluded that HS-Os-1 cells are originally apoptotic-resistant and that the cells possess a strong ability to scavenge for free radicals. To convert these cells to a state of apoptotic-susceptibility, a powerful oxidant such as hydrogen peroxide might exert such an effect in terms of the production of hydroxyl radicals in lysosomes in the cells as shown in our previous studies. The origin of the radioresistance of the human osteosarcoma cell line HS-Os-1 is considered to to be low degree of ROS formation following irradiation, reflecting the strong scavenging ability of these cells for free radicals including hydroxyl radicals.  相似文献   
36.
37.
ObjectiveA high coronary artery calcification score (CACS) may be associated with high mortality in patients undergoing hemodialysis (HD). Recently, effects of iron on vascular smooth muscle cell calcification have been described. We aimed to investigate the relationships between iron, CACS, and mortality in HD patients.MethodsWe studied 173 consecutive patients who were undergoing maintenance HD. Laboratory data and Agatston’s CACS were obtained at baseline for two groups of patients: those with CACS ≥400 (n = 109) and those with CACS <400 (n = 64). Logistic regression analyses for CACS ≥400 and Cox proportional hazard analyses for mortality were conducted.ResultsThe median (interquartile range) age and duration of dialysis of the participants were 67 (60–75) years and 73 (37–138) months, respectively. Serum iron (Fe) and transferrin saturation (TSAT) levels were significantly lower in participants with CACS ≥400 than in those with CACS <400, although the serum ferritin concentration did not differ between the groups. TSAT ≥21% was significantly associated with CACS ≥400 (odds ratio 0.46, p<0.05). TSAT ≥17%, Fe ≥63 µg/dL, and ferritin ≥200 ng/mL appear to protect against 5-year all-cause mortality in HD patients, independent of conventional risk factors of all-cause mortality (p < 0.05).ConclusionWe have identified associations between iron, CACS, and mortality in HD patients. Lower TSAT was found to be an independent predictor of CACS ≥400, and iron deficiency (low TSAT, iron, or ferritin) was a significant predictor of 5-year all-cause mortality in HD patients.  相似文献   
38.
We studied the pathogenesis of IRBP-induced experimental autoimmune uveoretinitis (EAU) by immunohistochemical detection of various immune cells using specific monoclonal antibodies to their surface markers and adhesion molecules. The following results were obtained: (1) During each stage of EAU, CD4 positive T cells predominated over CD8 positive T cells in the retina and the uvea. (2) One day prior to the clinical onset of disease, la positive cells began to appear in the ciliary body. (3) LFA-1 and ICAM-1 were expressed on intraocularly infiltrating cells. (4) ICAM-1 was also expressed on endothelial cells of uveal and retinal vessels. In addition, ICAM-1 was expressed on ciliary body epithelium and retinal pigment epithelium, a finding which may be associated with the breakdown of the blood-ocular barrier. In conclusion, the expression of LFA-1 and ICAM-1 in EAU demonstrates that adhesion molecules, such as these, play an important role in inflammatory ocular disease in vivo.  相似文献   
39.
Prior injection of an anticancer agent and Lipiodol mixture is a key point for the treatment of hepatocellular carcinoma (HCC). We therefore prepared a new, improved emulsion of Lipiodol containing a high dose ofcis-diamminedichloroplatinum (CDDP) and epirubicin by replacing the ionic contrast medium (Urografin 67) with a nonionic contrast medium (Iopamidol; Iopamiron 300) and adding phosphatidyl choline. This CDDP-epirubicin-Lipiodol emulsion (CELE) was examined pharmacologically and chemically with the following results. The size of these particles is less than 10 m (diameter) for up to 24 h; the release of 28%–34% of the CDDP and 80%–90% of the epirubicin was estimated in the dissolution test, and 85% of the CDDP and 35% of the epirubicin was retained in the organs in the moment calculation. CELE was injected into 58 HCC patients via a celiac angiographic catheter. In 36 of these patients, the CELE injection was followed by transcatheter arterial embolization (TAE) therapy. Following the administration of CELE as one-shot injection therapy for stage IV HCC, the 1-year survival rate was 59% and the 2-year survival rate was 27%. Moreover, in patients (stage II, 12; stage III, 8; stage IV, 16) who received CELE and subsequently underwent TAE therapy, the 1-year survival rate was 90% and the 2-year survival rate was 67%. The nonionic contrast medium with Lipiodol forms finer emulsified particles, and these particles are more capable of penetrating into the tumor. In addition, the greater pharmacological stability of these particles provides a slow-release effect and prolonged stability of their shape. Finally, theoretically, the use of two major anticancer agents such as CDDP and epirubicin showed a greater clinical effect in the treatment of HCC than either our earlier suspension or a single anticancer agent.Work presented at the Third International Symposium on Treatment of Liver Cancer, Seoul, Korea, 12–13 February 1993  相似文献   
40.
The purpose of this study is to determine the diagnostic accuracy for detection of culprit lesions in patients with unstable angina. Both ATP 201Tl SPECT and coronary angiography were performed in 51 patients with unstable angina pectoris within a week since the last attack. SPECT images were divided into 17 segments and the regional uptakes were scored semiquantitatively (0 = normal to 3 = no activity) and compared with the coronary angiographic findings. ATP 201Tl SPECT revealed decreased uptakes in 54 of 56 culprit lesions. The sensitivity, specificity and accuracy for detection of culprit lesions were 96.4%, 89.5% and 92.4%, respectively. Although adverse effects during ATP administration were complicated in 28 (54.9%) patients, all the complications were mild and resolved within two minutes. ATP 201Tl SPECT is sensitive and reliable method for detecting culprit lesions and can be performed safely even at acute phase in patients with unstable angina pectoris.  相似文献   
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