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Platinum (Pt) levels were determined in various tissues and body fluids obtained from a patient who died 181 days after cisplatin overdosing. The symptoms of cisplatin overdose, however, might have almost disappeared by day 40, and the patient’s death was ascribed to the recurrence of malignant lymphoma. Determination of Pt derived from cisplatin was performed by electrospray ionization mass spectrometry (ESI-MS) using silver (Ag) as internal standard. Pt and Ag complexed with diethyldithiocarbamate (DDC) in wetashed blood, and tissue solutions were extracted into isoamyl alcohol, and then acidified with oxalic acid. By injecting an aliquot of the isoamyl alcohol layer into a mass spectrometer in the direct flow injection mode, the quantitation was performed using the signals of Pt(DDC)3 + and Ag(DDC)2 + at m/z 639 and 403, respectively. The Pt levels ranged from 25ng/ml in blood to 2050ng/g wet weight in the liver of the patient, indicating that Pt remained at high levels in tissues, even after a period as long as 181 days after cisplatin overdosing.  相似文献   
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Angiotensin II receptor blockers (ARBs) are widely used for the treatment of hypertension. It is believed that treatment with an ARB increases the level of plasma angiotensin II (Ang II) because of a lack of negative feedback on renin activity. However, Ichikawa (Hypertens Res 2001; 24: 641-646) reported that long-term treatment of hypertensive patients with olmesartan resulted in a reduction in plasma Ang II level, though the mechanism was not determined. It has been reported that angiotensin 1-7 (Ang-(1-7)) potentiates the effect of bradykinin and acts as an angiotensin-converting enzyme (ACE) inhibitor. It is known that ACE2, which was discovered as a novel ACE-related carboxypeptidase in 2000, hydrolyzes Ang I to Ang-(1-9) and also Ang II to Ang-(1-7). It has recently been reported that olmesartan increases plasma Ang-(1-7) through an increase in ACE2 expression in rats with myocardial infarction. We hypothesized that over-expression of ACE2 may be related to a reduction in Ang II level and the cardioprotective effect of olmesartan. Administration of 0.5 mg/kg/day of olmesartan for 4 weeks to 12-week-old stroke-prone spontaneously hypertensive rats (SHRSP) significantly reduced blood pressure and left ventricular weight compared to those in SHRSP given a vehicle. Co-administration of olmesartan and (D-Ala7)-Ang-(1-7), a selective Ang-(1-7) antagonist, partially inhibited the effect of olmesartan on blood pressure and left ventricular weight. Interestingly, co-administration of (D-Ala7)-Ang-(1-7) with olmesartan significantly increased the plasma Ang II level (453.2+/-113.8 pg/ml) compared to olmesartan alone (144.9+/-27.0 pg/ml, p<0.05). Moreover, olmesartan significantly increased the cardiac ACE2 expression level compared to that in Wistar Kyoto rats and SHRSP treated with a vehicle. Olmesartan significantly improved cardiovascular remodeling and cardiac nitrite/ nitrate content, but co-administration of olmesartan and (D-Ala7)-Ang-(1-7) partially reversed this anti-remodeling effect and the increase in nitrite/nitrate. These findings suggest that olmesartan may exhibit an ACE inhibitory action in addition to an Ang II receptor blocking action, prevent an increase in Ang II level, and protect cardiovascular remodeling through an increase in cardiac nitric oxide production and endogenous Ang-(1-7) via over-expression of ACE2.  相似文献   
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近年来,虽然遭遇阻力,但日本国内对于中日战争时期日军在华实施性暴力的调查、研究工作还是取得了重要进展。以石田米子为中心的调查小组经过长期不懈的努力,对当年日军在山西省盂县实施性暴力的事实进行了确证和揭露。本文在介绍石田小组的工作及其意义的同时,还对战时日军的性暴力活动进行了分类,并结合史学理论探讨了利用口述史料研究中国近现代史的意义与可能性。  相似文献   
6.
We have found that steroid bolus withdrawal prior to graft reperfusion increased the incidence of acute cellular rejection (ACR). This study aims to clarify how initial steroid bolus (ISB) injection at reperfusion influences the kinetics of CD8(+) alloreactive immune responses immediately after living donor liver transplantation (LDLT). A total of 49 hepatitis C virus (HCV)-infected recipients were classified into 3 groups according to hierarchical clustering by preoperative CD8(+)CD45 isoforms. The naive T cell proportion was considerably higher in Group I than in Groups II and III, whereas Group II recipients had the highest effector memory (EM) T cells and Group III the highest effector T cells. The frequency of ACR was significantly higher in recipients without ISB than in those with ISB. In particular, the ACR rates were the highest in Group II without ISB. Following ISB, the proportion of effector T cells was promptly upregulated within 6 hours after graft reperfusion, simultaneously with the upregulation of CD27(-)CD28(-) subsets, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha and perforin expression, which significantly correlated with increasing interleukin (IL)-12 receptor beta 1 cells. These were then downregulated to below preoperative levels by tacrolimus (Tac) administered at 24 hours. These changes did not occur in the absence of ISB. In Group II without ISB, the downregulation of IL-12Rbeta1(+) cells was the greatest, consistent with the highest rates of ACR and mortality (60%). In conclusion, ISB must be done in place, especially in Group II with preexisting high EM T cells, to enable the development of early allograft acceptance.  相似文献   
7.
Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.  相似文献   
8.
An examination was made of neurogenesis in the anteroventral periventricular nucleus (AVPv) of the preoptic area of the rat using bromodeoxyuridine (BrdU), a thymidine analog, and a BrdU-specific antibody. Cells in the AVPv of adult rats were labeled with the antibody when BrdU was injected into pregnant rats once during day 13 to 18 of gestation, but not during day 10 to 12 nor 19 to 20 of gestation nor on postnatal day 1, indicating that neurogenesis of the AVPv occurs during a limited period from day 13 to 18 of gestation. Next, to examine the effects of androgen on neurogenesis, BrdU was injected once on day 15 into pregnant rats that also received injections of testosterone propionate (TP). The number of BrdU-labeled cells in the AVPv was similar in control female and male fetuses and female fetuses from pregnant rats that received daily injections of TP during days 14 to 16, when fetuses were examined on day 17 of gestation. These results suggest that the neurogenesis that was recognized by labeling with BrdU was not affected by the treatment with TP. On day 21 of gestation, BrdU-labeled cells in the AVPv of control male fetuses and female fetuses that received TP during days 14 to 18 were fewer in number than those in female fetuses of the control group, whereas treatments with TP during days 14 to 16 and during days 17 to 18 did not cause any significant decrease in number of BrdU-labeled cells. These findings support the hypothesis that elimination of a population of cells, for example, by cell death as described previously, is enhanced in male fetuses and in female fetuses treated with TP repetitively.  相似文献   
9.
An attempt was made to detect a pancreatic tumor antigen (PTA) in transplantable pancreatic adenocarcinomas induced by N-bis(2-hydroxypropyl)nitrosamine (DHPN) in hamsters. Antibody against antigenic protein was raised by immunizing rabbits with whole homogenate of the tumors transplanted into the back of hamsters. PTA was purified by affinity chromatography and shown to have the physicochemical properties of a glycoprotein with a molecular weight of 800,000, migrating in the beta regions upon agarose gel electrophoresis. Loss of immunological properties was observed after heating at 65 degrees C for 30 min. Enzyme immunoassay revealed that the levels of PTA in the serum and tissue showed a positive correlation with the induction of the presence of tumor, and size of the tumor. It is tentatively suggested that PTA values above 150 ng/ml serum are indicators of tumors, because in normal hamsters the PTA range is from 25 to 130 ng/ml serum. Immunohistochemically, PTA was demonstrated to be localized within the cytoplasm of epithelial tumor cells of well-differentiated tubular adenocarcinomas.  相似文献   
10.
Behcet's disease (BD) is characterized by recurrent oral aphthae, skin lesions, eye lesions, and genital ulceration. To determine the pathogenesis of BD, we performed histological and immunohistochemical studies of these mucocutaneous lesions, an assay of neutrophil activity, and HLA typing. Dense dermal or subcutaneous infiltrations of polymorphonuclear cells (PMN) without leukocytoclastic vasculitis were found in 28 of 57 lesions. Immunohistochemically, deposits of C3 on the vessels were found in 12 of 31 lesions. Deposits of immunoglobulin were not found except for one of IgM. C3 deposits and PMN infiltrations were significantly related (p<0.05). PMN activity by polarization was enhanced; however, the results did not show a significant relationship with the PMN infiltrations or the C3 deposits. The incidence of HLA-B51 was significantly high in BD, but no significant relationship was found between HLA-B51 and the results of other examinations. These results suggest that the pathogenesis of BD lesions differs from that of collagen diseases and that C3 deposits on the vessels may play an important role in the development of mucocutaneous lesions where PMN have mainly infiltrated.  相似文献   
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