Comparison of the biomechanical effect of posterior condylar offset and kinematics between posterior cruciate-retaining and posterior-stabilized total knee arthroplasty

Background

The effect of the changes in the femoral posterior condylar offset (PCO) on anterior–posterior (AP) translation and internal–external (IE) rotation in cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) remains unknown. The purpose of this study was to compare the kinematics in CR and PS TKA with respect to the difference in prosthetic design and PCO change through a computational simulation.

The application of SFDI and LSI system to evaluate the blood perfusion in skin flap mouse model

Lasers in Medical Science - The aim of this study is to evaluate whether the blood perfusion to tissues for detecting ischemic necrosis can be quantitatively monitored by spatial frequency domain...     

Hyperfractionated radiotherapy with concurrent chemotherapy for para-aortic lymph node recurrence in carcinoma of the cervix

PURPOSE: To evaluate efficacy, toxicity, and patterns of relapse in patients treated with hyperfractionated radiotherapy (HFRT) with concurrent chemotherapy for para-aortic lymph node (PALN) recurrence of cervical carcinoma. METHODS AND MATERIALS: Between September 1997 and October 2000, 12 cervical carcinoma patients with isolated PALN recurrence who had previously received radical or postoperative radiotherapy were treated with HFRT and concurrent chemotherapy. The initial FIGO stage was Stage IB in 4 (33%) patients, Stage IIA in 2 (17%), and Stage IIB in 6 (50%). The radiation field encompassed the gross recurrent PALN with the superior margin at the upper end of the T12 body and the inferior margin between L5 and S1. The fractionated dose was 1.2 Gy in 2 daily fractions, and the median total dose was 60 Gy. The weekly concurrent chemotherapy consisted of paclitaxel in 11 patients and cisplatin in 1. The median number of cycles of chemotherapy was 5. RESULTS: The latent period to PALN recurrence from the time of initial treatment for all patients ranged from 2 to 92 months (median: 12 months). One month after treatment, the clinical tumor response evaluated was complete in 33% (4/12) and partial in 67% (8/12). The 3-year overall survival rate and median survival were 19% and 21 months, respectively. The latent period to PALN recurrence was the only significant prognostic factor; the median survival of patients who relapsed in < or =24 months from the initial treatment of cervical carcinoma was 13 months vs. 45 months for those relapsed at >24 months (p = 0.026). Grade 3-4 hematologic toxicity developed in 2 patients. Six (50%) patients experienced Grade 2 nausea. There were no late gastrointestinal or neurologic complications during the follow-up period. Subsequent distant metastases after PALN treatment developed in 58% (7/12). CONCLUSION: HFRT of 60 Gy to PALN with concurrent chemotherapy could be regarded as an effective treatment modality without significant acute or late toxicity. Patients with a latent period >24 months until PALN recurrence had a more favorable survival rate than those with a latent period 相似文献   

Isocenter accuracy in frameless stereotactic radiotherapy using implanted fiducials

PURPOSE: The stereotactic radiotherapy (SRT) system verifies isocenter accuracy in patient space. In this study, we evaluate isocenter accuracy in frameless SRT using implanted cranial gold markers. MATERIALS AND METHODS: We performed frameless SRT on 43 intracranial tumor patients between August 1997 and December 2000. The treatment technique was determined by the tumor shape and volume, and by the location of critical organs. The coordinates of anterior-posterior and lateral port film were inputted to ISOLOC software, which calculated (1) the couch moves translation distance required to bring the target point to the isocenter, and (2) the intermarker distance comparisons between the CT study and the treatment machine films. We evaluated the isocenter deviation based on the error between orthogonal film target coordinates and isocenter coordinates. RESULTS: The mean treatment isocenter deviations (x, y, z) were -0.03, 0.14, and -0.04 mm, respectively. The systematic component isocenter standard deviations were 0.28, 0.31, and 0.35 mm (1 SD), respectively, and the random component isocenter standard deviations were 0.53, 0.52, and 0.50 mm (1 SD), respectively. CONCLUSIONS: The isocenter accuracy in the frameless SRT-implanted fiducial system is highly reliable and is comparable to that of other stereotactic radiosurgery systems.     

Evidence that myocardial Na/I symporter gene imaging does not perturb cardiac function.

Adenoviral Na/I symporter (NIS) gene transfer has emerged as a promising method for myocardial gene imaging but concern over possible perturbation of cardiac function persists. In this study, we addressed this issue with cultured cardiac cells and serial echocardiography, creatine kinase (CK) measurements, and histologic examination of rats intramyocardially injected with an adenovirus that expresses both NIS and enhanced green fluorescent protein (EGFP) (Ad.EGFP.NIS) or a control virus (Ad.EGFP). METHODS: H9C2 cardiac myoblasts differentiated into cardiomyocytes were evaluated for the effect of Ad.EGFP.NIS and Ad.EGFP infection on viable cell number and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Rats injected intramyocardially with 3 x 10(8) plaque-forming units of Ad.EGFP.NIS (n = 9) or Ad.EGFP (n = 8) underwent serial echocardiographic measurements of heart rate, left ventricular (LV) dimensions, ejection fraction (EF), and fractional shortening (FS) on the day before and on days 4 and 9 after gene transfer. Five Ad.EGFP.NIS rats also underwent repeated (123)I imaging from which ratios of cardiac to mediastinal counts (C/M ratios) were obtained. Separate rats underwent serial measurements of serum CK, myocardial myeloperoxidase assays, and microscopic assessment of inflammation. RESULTS: Cultured cardiac cells showed no change in cell viability or proliferation at 4 and 9 d after Ad.EGFP.NIS or Ad.EGFP infection compared with controls. (123)I scintigraphy demonstrated high cardiac radiouptake at Ad.EGFP.NIS injection sites by days 2 and 4 (C/M ratios, 5.0 +/- 0.6 and 5.1 +/- 1.0, respectively), followed by a complete loss of uptake by day 9 (C/M ratio, 1.4 +/- 0.0). Serial echocardiography revealed no difference in heart rate, LV dimensions, or functional parameters between Ad.EGFP.NIS and Ad.EGFP groups at any given time. Mild reductions in LVEF and LVFS by day 9 compared with baseline were similar for both Ad.EGFP (88.2% +/- 6.4% vs. 79.6% +/- 5.0% for LVEF and 0.55 +/- 0.10 vs. 0.44 +/- 0.05 for LVFS) and Ad.EGFP.NIS groups (88.0% +/- 5.4% vs. 78.7% +/- 4.6% for LVEF and 0.54 +/- 0.09 vs. 0.42 +/- 0.05 for LVFS). Serial serum CK and myocardial myeloperoxidase activities were not elevated in either group, in contrast to substantial increases found after ischemia-reperfusion injury. Histology revealed similar mild inflammatory cell infiltration restricted to the injection site for both groups. CONCLUSION: The results of this study demonstrate that myocardial NIS gene imaging does not cause significant myocardial injury or perturbed cardiac function, other than mild effects likely due to adenoviral vector-associated host response. Thus, this practical and convenient reporter gene strategy can be used safely for noninvasive myocardial gene imaging in living subjects.     

Differential cytokine levels and immunoreactivities against Mycobacterium tuberculosis antigens between tuberculous and malignant effusions

Much effort has been devoted to the identification of immunologically important factors in tuberculous pleurisy (TBP) and malignant pleurisy (MP) to improve the differential diagnosis of the two major causes of lymphocyte-dominant pleurisy. This study evaluated the immunoreactivity and potential diagnostic utility of both host (cytokines and chemokines) and pathogen (mycobacterial proteins) factors in pleural effusions. Effusion samples were collected from 41 patients with MP caused by lung cancer and from 81 patients with TBP. The concentrations of nine cytokines and chemokines (interleukin (IL)-12 p40, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, IL-6, IL-10, CXCL8/IL-8, CXCL10/IP-10, CCL3/MIP-1alpha, and CCL4/MIP-1beta) and antibody responses (IgG, IgM, and IgA) against five Mycobacterium tuberculosis antigens (early secreted antigenic target (ESAT)-6, 30-kDa, MTB12, 38-kDa, and a heparin-binding hemagglutinin (HBHA)) were determined in pleural fluids using enzyme-linked immunosorbent assays (ELISA). In the logistic regression, IFN-gamma (odds ratio, 7.178; 95% confidence interval (CI), 2.258-22.817; p=0.001), IL-12 p40 (odds ratio, 11.037; 95% CI, 3.38-36.037; p<0.001), and IL-6 (odds ratio, 3.295; 95% CI, 1.147-9.463; p=0.027) were found to be statistically significant cytokines predicting tuberculous from malignant effusions. Although IgG responses to all of the M. tuberculosis antigens tested were significantly higher in effusions from TBP (p<0.001) compared with those from MP, the logistic regression showed IgG levels for ESAT-6 and MTB12 to be statistically significant for differentiation of TBP from MP. HBHA showed the highest sensitivity of IgM antibody responses in TBP in comparison with other antigens. These data indicate that selected mycobacterial antigens (ESAT-6 and MTB12) and cytokine markers (IFN-gamma, IL-12p40, and IL-6) provide useful information for differentiating tuberculous and malignant effusions in clinical practice.     

Preparation and properties of polyaniline doped with poly(thiophenylenesulfonic acid)

A novel polyaromatic acid, poly(thiophenylenesulfonic acid) (PTPSA), prepared from a soluble precursor of poly(arylenesulfonium salt) was employed as a dopant for polyaniline (PAn). The electro-oxidative polymerization of aniline in PTPSA aqueous solution gives an electroactive PAn/PTPSA composite with three redox couples at 0.16, 0.53, and 0.71V (vs. SCE). Composites of different molar ratio ([SO₃H]/[An] = 0.10, 0.21, 0.42, 0.50, 0.83, 1.67) was prepared in order to confirm the transformation from the emeraldine base to its PTPSA salt, where a quantitative doping reaction was observed by means of UV-VIS and IR measurements. The thermogravimetric analysis revealed that the composites do not decompose up to 200°C in nitrogen atmosphere. The composite ([SO₃H]/[An] = 0.50) shows an electrical conductivity of 1.5 S·cm^–1 at 30°C and 3.0×10^–1 S·cm^–1 at 170°C. The composite retains its conductivity after heating at 150°C for 24 h.     

Pharmacokinetics and biodistribution of a small radioiodine labeled nerve growth factor fragment

Nerve growth factor (NGF) exerts various actions on neuronal and non-neuronal tissues and has potential therapeutic utility, but difficulties in using the whole protein have stimulated interest in small NGF fragments. We radioiodinated a small cyclic peptide derived from NGF using the Bolton-Hunter method [125I-C(92-96)], and confirmed binding to high affinity NGF receptors by cross-linkage analysis. Pharmacokinetic characteristics in intravenously injected mice were T 1/2 alpha 5.2 min, T 1/2beta 121.3 min, clearance 11.8+/-0.5 ml/min, and volume of distribution 69.7+/-4.6 ml. Dose-proportionate increases in areas-under-curve and peak-concentrations indicated linear pharmacokinetics. Biodistribution data revealed that clinically relevant doses allowed C(92-96) accumulation sufficient to elicit biological responses in receptor expressing organs including the lungs, liver, spleen, and pancreas.     

Preoperative chemoradiation using oral capecitabine in locally advanced rectal cancer

PURPOSE: Capecitabine (Xeloda) is a new orally administered fluoropyrimidine carbamate that was rationally designed to exert its effect by tumor-selective activation. We attempted to evaluate the efficacy and toxicity of preoperative chemoradiation using capecitabine in locally advanced rectal cancer. METHODS AND MATERIALS: Between July 1999 and March 2001, 45 patients with locally advanced rectal cancer (cT3/T4 or N+) were treated with preoperative chemoradiation. Radiation of 45 Gy/25 fractions was delivered to the pelvis, followed by a 5.4 Gy/3 fractions boost to the primary tumor. Chemotherapy was administered concurrent with radiotherapy and consisted of 2 cycles of 14-day oral capecitabine (1650 mg/m(2)/day) and leucovorin (20 mg/m(2)/day), each of which was followed by a 7-day rest period. Surgery was performed 6 weeks after the completion of chemoradiation. RESULTS: Thirty-eight patients received definitive surgery. Primary tumor and node downstaging occurred in 63% and 90% of patients, respectively. The overall downstaging rate, including both primary tumor and nodes, was 84%. A pathologic complete response was achieved in 31% of patients. Twenty-one patients had tumors located initially 5 cm or less from the anal verge; among the 18 treated with surgery, 72% received sphincter-preserving surgery. No Grade 3 or 4 hematologic toxicities developed. Other Grade 3 toxicities were as follows: hand-foot syndrome (7%), fatigue (4%), diarrhea (4%), and radiation dermatitis (2%). CONCLUSION: These preliminary results suggest that preoperative chemoradiation with capecitabine is a safe, well-tolerated, and effective neoadjuvant treatment modality for locally advanced rectal cancer. In addition, this preoperative treatment has a considerable downstaging effect on the tumor and can increase the possibility of sphincter preservation in distal rectal cancer.