锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡

电镜观察了锌酞菁脂质体光动力作用引起小鼠ＭＳ－２纤维肉瘤的形态学变化。发现其作用很强，并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡（ａｐｏｐｔｏｓｉｓ，ｐｒｏｇｒａｍｍｅｄｃｅｌｄｅａｔｈ）的特点：胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识，但其详细的发生机制和调节途径有待阐明。     

Determination of the prognostic value of [(18)F]fluorodeoxyglucose uptake by using positron emission tomography in patients with non-small cell lung cancer

The aim of this study was to determine whether quantitative information obtained from [(18)F]fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) has a prognostic significance for patients with non-small cell lung cancer (NSCLC). We investigated (18)F-FDG PET imaging of 73 patients with NSCLC. The maximum standardized uptake value (SUV(max)) was significantly different between the histopathological types of tumour (squamous cell carcinoma (n=37, 12.4+/-5.1), adenocarcinoma (n=30, 8.2+/-5.8), bronchioloalveolar carcinoma (n=4, 2.6+/-1.7), <0.01). In the univariate analysis of all patients, staging (P=0.0001), tumour cell type (P=0.013), and a SUV(max) greater than 7 (P=0.0011) was correlated with survival. However, a multivariate analysis identified staging and SUV(max) greater than 7 were affected survival adversely. The mortality rate of patients with group I disease (stage I to stage IIIA) was 5.8 times lower than that of patients with group II disease (stage IIIB to stage IV). Patients with a high SUV(max) (> or =7) had a 6.3 times higher mortality than those with a low SUV(max)(<7). By multivariate analysis of patients with squamous cell carcinoma, only grouping affected survival (P=0.008, relative risk=4.3). In the case of adenocarcinoma, the SUV(max) (>10) correlated exclusively with poorer survival (P=0.031, relative risk=11.152). (18)F-FDG uptake correlated with survival in NSCLC. Especially in adenocarcinomas, the SUV(max) was complementary to other known prognostic factors.     

Quantitative CT with finite element analysis: towards a predictive tool for bone remodelling around an uncemented tapered stem

Purpose

We used quantitative CT in conjunction with finite element analysis to provide a new tool for assessment of bone quality after total hip arthroplasty in vivo. The hypothesis of this prospective five-year study is that the combination of the two modalities allows 3D patient-specific imaging of cortical and cancellous bone changes and stress shielding.

Method

We tested quantitative CT in conjunction with finite elements on a cohort of 29 patients (31 hips) who have been scanned postoperatively and at one year, two years and five years follow-up. The method uses cubic Hermite finite element interpolation for efficient mesh generation directly from qCT datasets. The element Gauss points that are used for the geometric interpolation functions are also used for interpolation of osteodensitometry data.

Results

The study showed changes of bone density suggestive of proximal femur diaphysis load transfer with osteointegration and moderate metaphyseal stress shielding. Our model revealed that cortical bone initially became porous in the greater trochanter, but this phenomenon progressed to the cortex of the lesser trochanter and the posterior aspect of the metaphysis. The diaphyseal area did not experience major change in bone density for either cortical or cancellous bone.

Conclusion

The combination of quantitative CT with finite element analysis allows visualization of changes to bone density and architecture. It also provides correlation of bone density/architectural changes with stress patterns enabling the study of the effects of stress shielding on bone remodelling in vivo. This technology can be useful in predicting bone remodeling and the quality of implant fixation using prostheses with different design and/or biomaterials.     

Surgical strategy of the treatment of atypical femoral fractures

The atypical femoral fracture (AFF) has been attracting significant attention because of its increasing incidence; additionally, its treatment is challenging from biological and mechanical aspects. Although surgery is often required to manage complete AFFs, clear guidelines for the surgical treatment of AFFs are currently sparse. We reviewed and described the surgical treatment of AFFs and the surveillance of the contralateral femur. For complete AFFs, cephalomedullary intramedullary nailing spanning the entire length of the femur can be used. Various surgical techniques to overcome the femoral bowing common in AFFs include a lateral entry point, external rotation of the nail, and the use of a nail with a small radius of curvature, or a contralateral nail. In the case of a narrow medullary canal, severe femoral bowing, or pre-existing implants, plate fixation may be considered as an alternative. For incomplete AFFs, prophylactic fixation depends on several risk factors, such as a subtrochanteric location, presence of a radiolucent line, functional pain, and condition of the contralateral femur; the same surgical principles as those in complete AFFs can be applied. Finally, once AFF is diagnosed, clinicians should recognize the increased risk of contralateral AFFs, and close surveillance of the contralateral femur is recommended.     

Total hip reconstruction in the anatomically distorted hip

Recent reports in the literature strongly support the idea that cement is the optimum form of fixation of the femoral component in total hip replacement. For hybrid total hip arthroplasty, we used a cemented cup instead of an uncemented cup since this was inevitable in cases of poorly developed acetabulum. The uncemented cone femoral component is also beneficial in cases of extremely narrow and cylindrical configuration of the medullary cavity of untreated congenital dislocation of the hips (CDH) and tuberculosis or septic arthritis in childhood. We reviewed the clinical result of a consecutive series of patients with cemented total hip arthroplasty (THA) compared with recent studies on hybrid reconstruction using survivorship analysis. This subsequent study involved a hybrid uncemented Wagner cone femoral component and a cemented acetabular component with roof reinforcement by additional impacted cancellous allograft with hydroxyapatite (HA). We believe that early failure of the cemented components was due to an adverse effect of thin cement mantles around cemented femoral stems as well as the cemented cup in THA. In addition, 8 patients who received our modification of the Charnley CDH component had poor results even though we reduced the stem geometry and thickness. Furthermore, intraoperative fracture and splitting of the proximal femur was a major complication during implantation. Contrary to expectations, the results of these hybrid reconstructions were extremely encouraging (average follow-up period of 2–4.5 years). In addition to our experience of the cemented versus hybrid THA involving the uncemented Wagner femoral component, we have determined positive indications for the untreated and severely distorted anatomy of bilateral CDH for which surgical interventions for reconstruction were not recommended before.     

Image quality assessment of ultra low-dose chest CT using sinogram-affirmed iterative reconstruction

Objectives

To assess the image quality of ultra-low-dose computed tomography (ULDCT) using sinogram-affirmed iterative reconstruction (SAFIRE) compared to reduced dose CT (RDCT).

Methods

Eighty-one consecutive patients underwent non-enhanced ULDCT using 80 kVp and 30 mAs and contrast-enhanced RDCT using automated tube potential selection and tube current modulation. CT images were reconstructed with SAFIRE. Image noise and subjective image quality of normal structures and various pulmonary lesions were assessed.

Results

The mean effective doses were 0.29?±?0.03 and 2.88?±?1.11 mSv for ULDCT and RDCT, respectively. ULDCT had significantly higher noise (p?<?0.001). Image quality of five normal structures was diagnostic in 91.1 % of ULDCT and 100 % of RDCT. With ULDCT, the frequencies of non-diagnostic image quality were 2.0 (1/50), 4.6 (13/280), 25.5 (14/55), and 40.0 (8/20)% for BMIs of?<?20, 20–25, 25–30, and >30. In the assessment of pulmonary lesions, non-diagnostic image quality was observed for 11.2 % of all lesions, 60.9 % of decreased attenuation (significantly more frequent for upper lung lesions), and 23.5 % of ground-glass nodules.

Conclusion

ULDCT generates diagnostic images in patients with a BMI ≤25, but is of limited use for lesions with decreased attenuation, ground-glass nodules, or those located in the upper lobe.

Key Points

? Iterative reconstruction enables ultra-low-dose CT (ULDCT) with very low radiation doses. ? Image quality of ULDCT depends on the patient body mass index (BMI). ? Selection of kVp and mAs depends on both BMI and lesion type. ? Diagnosis of pulmonary emphysema or ground-glass nodules requires higher radiation doses.     

Interleukin-6 predicts hypoalbuminemia, hypocholesterolemia, and mortality in hemodialysis patients

Low serum albumin and low serum cholesterol levels are among the most consistent predictors of mortality in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Hypoalbuminemia is often interpreted as a marker of poor nutrition, but serum albumin and cholesterol levels can also be low as part of a cytokine-mediated acute-phase reaction to acute or chronic inflammation. Here we report the results from a 900-day prospective study designed to determine whether tumor necrosis factor-alfa (TNF-alpha) and interleukin-6 (IL-6) predict serum albumin and cholesterol levels and mortality in a group of 90 ambulatory, adult hemodialysis patients with no acute infection, hospitalization or surgery, and no known acquired immunodeficiency syndrome (AIDS), malignancy, or liver disease. Measurable levels of TNF-alpha and/or IL-6 were found in 89 of 90 patients. Significant relationships were found between TNF-alpha and IL-6 and the degree of hypoalbuminemia and dyslipoproteinemia. IL-6 was the strongest predictor of mortality in univariate and multivariate analysis, followed by age, albumin level, and body mass index (BMI). Although the cause of hypercytokinemia was not addressed in this study, the data support the view that hypoalbuminemia and hypocholesterolemia are negative acute-phase responses to inflammatory stimuli. These results suggest that efforts to identify the nature of the stimuli for cytokine production and to lower cytokine levels in hemodialysis patients might be effective in improving the survival of patients undergoing hemodialysis.     

Primary tumors and mediastinal lymph nodes after neoadjuvant concurrent chemoradiotherapy of lung cancer: serial CT findings with pathologic correlation

PURPOSE: The purpose of this work was to describe the changes of primary tumor and mediastinal lymph nodes on CT after neoadjuvant concurrent chemoradiotherapy and to correlate the CT findings with pathology. METHOD: Twenty-one consecutive patients [N2 disease (n = 19) or resectable T4 and N2 disease (n = 2)] with non-small cell lung cancer underwent neoadjuvant concurrent chemoradiotherapy. Changes of primary tumor and mediastinal nodes before and after the therapy were assessed using CT. The CT findings were correlated with pathologic findings. RESULTS: With neoadjuvant therapy, decrease in T stage was achieved in 9 of 21 (43%) patients on CT. On pathology, the remaining tumor consisted mostly of fibrosis and necrosis with little proportion of viable tumor cells (mean volume 17%, range 0-55%). Decrease in nodal stage was achieved in 14 of 21 (67%) patients on pathologic examination. Seven patients had cancer cells in mediastinal lymph nodes: in 6 of 9 (67%) patients with adenocarcinoma and 1 of 12 (8%) patients with squamous cell carcinoma (p = 0.016). CONCLUSION: With neoadjuvant concurrent chemoradiotherapy, the remaining tumor consists mostly of fibrosis or necrosis. Decreased nodal stage on pathology is achieved especially in patients with N2 disease of squamous cell carcinoma. The CT findings of the tumor and mediastinal nodes are not helpful in predicting the pathology after the therapy.