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71.
PURPOSE: For the treatment of Stage I non-small-cell lung cancers, a Phase I/II study of carbon ion irradiation was undertaken. In the present study, we focus on posttreatment radiographic lung damage: specifically, its timing, features, and relation to dose-volume factors. MATERIALS AND METHODS: Forty-three patients with 44 Stage I non-small-cell lung cancers were treated with carbon ion irradiation ranging from 59.4 to 95.4 photon Gy equivalent dose (GyE) in 18 fractions over 6 weeks, according to our dose escalation protocols. Primary lesions were irradiated by 2-4 portals. Follow-up evaluation with computed tomography (CT) was sequentially performed to assess changes in the lung. CT findings were classified into two categories: pulmonary reaction and pleural reaction. A dose-volume histogram for each patient was calculated, using a three-dimensional CT planning system. Statistical analysis was conducted using Spearman's rank test. RESULTS: The median appearance period of pulmonary reactions was 3 months after the start of carbon ion irradiation, whereas the maximum period was 6 months. The severity of pulmonary reactions statistically correlated with lung volumes irradiated no less than 20 GyE (vol. 20) and 40 GyE (vol. 40) (p = 0.017 and p = 0.0089). Geometrically unique findings in the irradiated fields were observed in 7 patients (16%). The median appearance period of pleural reactions was 4 months after the start of carbon ion irradiation. The occurrence of pleural reactions significantly correlated with planning target volume (p = 0.000098), vol. 20 (p = 0.00011), and vol. 40 (p = 0.00097). CONCLUSIONS: Lung damage after carbon ion irradiation was observed in the parenchyma and in the pleura. The severity of pulmonary reactions was correlated with dose-volume factors. These findings might provide useful information in the planning and management of carbon ion irradiation.  相似文献   
72.
OBJECTIVE: CYP2C9 is a polymorphic enzyme, and CYP2C9*3 is associated with decreased metabolic activity. In addition to the impaired metabolism, we investigated whether the CYP2C9*3 exhibited altered inhibitory susceptibility compared with CYP2C9*1. METHOD: In the present study, CYP2C9.1 and CYP2C9.3 were expressed in yeast. Using typical CYP2C9 substrates (diclofenac, tolbutamide and S-warfarin) and a potent CYP2C9 inhibitor (nicardipine), the Ki values for nicardipine on the three metabolisms in CYP2C9*1 and CYP2C9*3 were determined. RESULT: The ratios of Ki(CYP2C9*3)/Ki(CYP2C9*1) on tolbutamide, diclofenac and S-warfarin metabolisms were 1.2, 3.1 and 0.8, respectively. CONCLUSION: In conclusion, there are no significant differences in the inhibitory susceptibility between the two CYP2C9 enzymes.  相似文献   
73.
Chromosomal translocations involving the immunoglobulin heavy chain gene ( IgH ) and nonrandom protooncogene loci are the hallmark of genetic alterations found not only in multiple myeloma (MM), but also in premalignant stages of MM, including monoclonal gammopathy of undetermined significance (MGUS) and smoldering myeloma (SMM). We studied the frequency of IgH (14q32) rearrangements and their partner chromosomes in 16 Japanese patients with MGUS (13 cases), and SMM (3 cases) by means of interphase double-color fluorescence in situ hybridization (DCFISH) applied to purified plasma cells and using CD138-bead selection. IgH rearrangement was recognized in nine of the patients (56.3%). Protooncogene loci juxtaposed to IgH were identified in seven cases including CCND1 (11q13) in six cases and FGFR3 (4p16) in one. Four out of the six t(11;14)-positive cases showed nuclear staining of the cyclin D1 protein, whereas none of the seven t(11;14)-negative cases did. Moreover, neither MUM1 (6p25)- IgH nor MAFB (20q11)- IgH fusion signals were observed. This suggests to us that cyclin D1 deregulation due to the presence of t(11;14) is involved in the early development of plasma cell neoplasms, and that this event alone is not enough for the development of symptomatic myeloma. (Cancer Sci 2003; 94: 350-354)  相似文献   
74.
Experimental autoimmune myocarditis (EAM) has been used as a model for human myocarditis. We previously demonstrated that blockade of B7/CD28 or CD40/CD40 ligand (CD40L) had a potential preventive effect on EAM, but less therapeutic effect on ongoing EAM. Thus, we searched for the involvement of other costimulatory molecules in EAM. We demonstrated the expression of inducible costimulator (ICOS)/ICOSL molecules in the lymph nodes, spleen, and heart in the EAM rat. We constructed adenovirus vectors containing ICOSIg (Adex1CAICOSIg) to achieve effective inhibition of ICOS/ICOSL interaction, and examined the effects of Adex1CAICOSIg on EAM. Adex1CAICOSIg treatment shortly after the immunization did not inhibit the onset and severity of EAM compared to control rats. On the other hand, delayed treatment with Adex1CAICOSIg significantly inhibited ongoing EAM. The survival rate in rats treated with Adex1CAICOSIg was significantly higher than that of the control group. Furthermore, the affected area ratio of the Adex1CAICOSIg treatment group was significantly lower than that of the control group. This study indicates that ICOS/ICOSL costimulation makes an important contribution to the progression of EAM and that the blockade of this pathway by gene transfer has therapeutic potential for ongoing autoimmune myocarditis.  相似文献   
75.
An autopsy study of glutaric aciduria type II in a 62-day-old Japanese boy is presented. The diagnosis was made by analysis of organic acids in the urine. Immunoblot analysis of liver homogenate confirmed the diagnosis, revealing absence of electron-transferring flavoprotein dehydrogenase. The major findings were fatty changes of variable degree in many organs and tissues, the most severe being found in cardiac myocytes, hepatocytes, renal tubular epithelium, and skeletal muscle fibers. Other pertinent findings included multicystic and dysplastic kidney, pulmonary alveolar proteinosis, and spongiosis and gliosis of the spinal cord. The thymus was markedly depleted, and lymphocytes in the lymph nodes were mainly B cells. Although some of these changes may have been secondary to the sepsis and immunosuppression complicating 2 months of intensive care, the abnormal organic acid metabolism with severe acidosis may have been a significant contributing factor.  相似文献   
76.
77.
A 58-year-old female was admitted with an abrupt onset of chest and back pain. The CT scan of the chest showed aortic dissection of the ascending aorta and proximal aortic arch, but the false lumen of the aortic dissection had already been occluded by a blood clot. After admission, she complained of chest pain with hemoptysis and presented facial edema and the distention of the neck veins. The pulmonary angiogram showed complete occlusion of the right pulmonary artery at the proximal segment. These findings were interpreted as pulmonary embolism. She was treated with intravenous heparin and urokinase, but these treatments did not demonstrate any improvement. She underwent a surgical exploration on the fourth hospital day. During surgery, the right pulmonary artery was discovered to be compressed and occluded by the large dissecting aneurysm of the ascending aorta. In addition, hematoma was seen between the right pulmonary artery. The ascending aorta and pulmonary trunk, which was injured in the operative procedure, were replaced with an artificial graft successfully. Postoperative pulmonary angiogram showed no stenosis of right pulmonary artery. The occlusion of the pulmonary artery by an acute dissecting aneurysm is an extremely rare complication and it is often wrongly diagnosed as pulmonary embolism. In such cases, the correct diagnosis and prompt surgical treatment is essential and antithrombolytic and anticoagulant therapy should be avoided.  相似文献   
78.

Aim

We reviewed our experience in redo valvular surgery to evaluate trends in short‐ and long‐term outcomes.

Methods

We reviewed 414 patients (mean age, 62.8 ± 13.6 years) who underwent redo valvular surgery in the past 25 years. A total of 301 patients (54.2%) underwent first‐time redo valvular surgeries; 178 (32.1%) were second redos, 60 (10.8%) were third redos, and 16 were fourth redos (2.9%). The mean follow‐up period was 6.8 ± 6.3 years.

Results

Hospital mortality was 5.8%. New York Heart Association (NYHA) class III/IV (P = 0.0007, odds ratio = 4.403) and hemodialysis (P = 0.0383, odds ratio = 7.196) were risk factors for hospital death. Long‐term survival rates at 15 and 20 years were 64.7% ± 4.3% and 59.1% ± 5.0%, respectively. Predictors of late death were first time redo (P = 0.0076, hazard ratio = 0.422) and age younger than 61 years (P = 0.0005, hazard ratio = 0.229). There were significant differences in long‐term survival between NYHA classes I/II and III/IV (log‐rank test, P = 0.0419) and between the time from redo surgery (log‐rank test, P = 0.0189) and age (log‐rank test, P = 0.0001).

Conclusions

The hospital mortality rate for redo valve surgery has improved. Early referral for redo surgery can contribute to improving early and late outcomes.  相似文献   
79.
80.
BACKGROUND: The role of various proteases in the pathogenesis of Alzheimer's disease is well documented. Recently, many members of the human tissue kallikrein family, a group of 15 secreted serine proteases, were found to be highly expressed in the central nervous system (CNS). Some of these enzymes can be measured in cerebrospinal fluid (CSF) by using ELISA-type methodologies. METHODS: We quantified various kallikreins in CSF of 20 patients with Alzheimer's disease (AD), 16 patients with frontotemporal dementia (FTD), and 15 controls. We then correlated the levels of various kallikreins with presence of AD or FTD. Among all kallikreins measured, detectable levels in CSF were identified for kallikreins hK6, hK7, and hK10. Other tested kallikreins (hK5, hK8, hK11, and hK13) were unmeasurable. The most notable differences between kallikrein levels in CSF and the three groups of subjects were seen between controls and FTD patients for hK6 (decrease in FTD; P = 0.017), controls and FTD patients for hK7 (decrease in FTD; P < 0.001), and controls and AD patients for hK7 (decrease in AD; P = 0.019). In addition, significant differences were seen between FTD patients or control subjects and patients with AD patients for hK10 (increase in AD; P < 0.02). Approximately half of the AD patients had CSF hK10 levels that were higher than all patients with FTD except one and all control subjects except two. Various kallikrein concentrations in CSF were correlated, the strongest correlation seen between hK6 and hK7 (r(s) = 0.58). We also observed a statistically significant association between decreasing hK7 concentration in CSF and possession of one or two ApoE4 alleles (P = 0.014). CONCLUSIONS: We demonstrate for the first time significant alterations of hK6, hK7, and hK10 concentration in CSF of patients with AD and FTD. Notably, all three kallikreins (hK6, hK7, and hK10) are decreased in CSF of FTD patients and hK10 is increased in CSF of AD patients, in comparison to control subjects. The possible connection between these enzymes and the pathogenesis and progression of AD and FTD needs to be further investigated.  相似文献   
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