181 research outputs found
124I-HuCC49deltaCH2 for TAG-72 antigen-directed positron emission tomography (PET) imaging of LS174T colon adenocarcinoma tumor implants in xenograft mice: preliminary results
<p>Abstract</p> <p>Background</p> <p><sup>18</sup>F-fluorodeoxyglucose positron emission tomography (<sup>18</sup>F-FDG-PET) is widely used in diagnostic cancer imaging. However, the use of <sup>18</sup>F-FDG in PET-based imaging is limited by its specificity and sensitivity. In contrast, anti-TAG (tumor associated glycoprotein)-72 monoclonal antibodies are highly specific for binding to a variety of adenocarcinomas, including colorectal cancer. The aim of this preliminary study was to evaluate a complimentary determining region (CDR)-grafted humanized C<sub>H</sub>2-domain-deleted anti-TAG-72 monoclonal antibody (HuCC49deltaC<sub>H</sub>2), radiolabeled with iodine-124 (<sup>124</sup>I), as an antigen-directed and cancer-specific targeting agent for PET-based imaging.</p> <p>Methods</p> <p>HuCC49deltaC<sub>H</sub>2 was radiolabeled with <sup>124</sup>I. Subcutaneous tumor implants of LS174T colon adenocarcinoma cells, which express TAG-72 antigen, were grown on athymic Nu/Nu nude mice as the xenograft model. Intravascular (i.v.) and intraperitoneal (i.p.) administration of <sup>124</sup>I-HuCC49deltaC<sub>H</sub>2 was then evaluated in this xenograft mouse model at various time points from approximately 1 hour to 24 hours after injection using microPET imaging. This was compared to i.v. injection of <sup>18</sup>F-FDG in the same xenograft mouse model using microPET imaging at 50 minutes after injection.</p> <p>Results</p> <p>At approximately 1 hour after i.v. injection, <sup>124</sup>I-HuCC49deltaC<sub>H</sub>2 was distributed within the systemic circulation, while at approximately 1 hour after i.p. injection, <sup>124</sup>I-HuCC49deltaC<sub>H</sub>2 was distributed within the peritoneal cavity. At time points from 18 hours to 24 hours after i.v. and i.p. injection, <sup>124</sup>I-HuCC49deltaC<sub>H</sub>2 demonstrated a significantly increased level of specific localization to LS174T tumor implants (p = 0.001) when compared to the 1 hour images. In contrast, approximately 50 minutes after i.v. injection, <sup>18</sup>F-FDG failed to demonstrate any increased level of specific localization to a LS174T tumor implant, but showed the propensity toward more nonspecific uptake within the heart, Harderian glands of the bony orbits of the eyes, brown fat of the posterior neck, kidneys, and bladder.</p> <p>Conclusions</p> <p>On microPET imaging, <sup>124</sup>I-HuCC49deltaC<sub>H</sub>2 demonstrates an increased level of specific localization to tumor implants of LS174T colon adenocarcinoma cells in the xenograft mouse model on delayed imaging, while <sup>18</sup>F-FDG failed to demonstrate this. The antigen-directed and cancer-specific <sup>124</sup>I-radiolabled anti-TAG-72 monoclonal antibody conjugate, <sup>124</sup>I-HuCC49deltaC<sub>H</sub>2, holds future potential for use in human clinical trials for preoperative, intraoperative, and postoperative PET-based imaging strategies, including fused-modality PET-based imaging platforms.</p
Enhancement of metastatic ability by ectopic expression of ST6GalNAcI on a gastric cancer cell line in a mouse model
ST6GalNAcI is a sialyltransferase responsible for the synthesis of sialyl Tn (sTn) antigen which is expressed in a variety of adenocarcinomas including gastric cancer especially in advanced cases, but the roles of ST6GalNAcI and sTn in cancer progression are largely unknown. We generated sTn-expressing human gastric cancer cells by ectopic expression of ST6GalNAcI to evaluate metastatic ability of these cells and prognostic effect of ST6GalNAcI and sTn in a mouse model, and identified sTn carrier proteins to gain insight into the function of ST6GalNAcI and sTn in gastric cancer progression. A green fluorescent protein-tagged human gastric cancer cell line was transfected with ST6GalNAcI to produce sTn-expressing cells, which were transplanted into nude mice. STn-positive gastric cancer cells showed higher intraperitoneal metastatic ability in comparison with sTn-negative control, resulting in shortened survival time of the mice, which was mitigated by anti-sTn antibody administration. Then, sTn-carrying proteins were immunoprecipitated from culture supernatants and lysates of these cells, and identified MUC1 and CD44 as major sTn carriers. It was confirmed that MUC1 carries sTn also in human advanced gastric cancer tissues. Identification of sTn carrier proteins will help understand mechanisms of metastatic phenotype acquisition of gastric cancer cells by ST6GalNAcI and sTn
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Motor phenotype of LRRK2 G2019S carriers in early-onset Parkinson disease
Objective: To determine the motor phenotype of LRRK2 G2019S mutation carriers. LRRK2 mutation carriers were previously reported to manifest the tremor dominant motor phenotype, which has been associated with slower motor progression and less cognitive impairment compared with the postural instability and gait difficulty (PIGD) phenotype. Design: Cross-sectional observational study. Setting: Thirteen movement disorders centers. Participants: Nine hundred twenty-five early-onset Parkinson disease cases defined as age at onset younger than 51 years. Main Outcome Measures: LRRK2 mutation status and Parkinson disease motor phenotype: tremor dominant or PIGD. Demographic information, family history of Parkinson disease, and the Unified Parkinson's Disease Rating Scale score were collected on all participants. DNA samples were genotyped for LRRK2 mutations (G2019S, I2020T, R1441C, and Y1699C). Logistic regression was used to examine associations of G2019S mutation status with motor phenotype adjusting for disease duration, Ashkenazi Jewish ancestry, levodopa dose, and family history of Parkinson disease. Results: Thirty-four cases (3.7%) (14 previously reported) were G2019S carriers. No other mutations were found. Carriers were more likely to be Ashkenazi Jewish (55.9% vs 11.9%; P < .001) but did not significantly differ in any other demographic or disease characteristics. Carriers had a lower tremor score (P = .03) and were more likely to have a PIGD phenotype (92.3% vs 58.9%; P = .003). The association of the G2019S mutation with PIGD phenotype remained after controlling for disease duration and Ashkenazi Jewish ancestry (odds ratio, 17.7; P < .001). Conclusion: Early-onset Parkinson disease G2019S LRRK2 carriers are more likely to manifest the PIGD phenotype, which may have implications for disease course
A randomized, double-blind, placebo-controlled trial of coenzyme Q10 in Huntington disease
Objective: To test the hypothesis that chronic treatment of early-stage Huntington disease (HD) with high-dose coenzyme Q10 (CoQ) will slow the progressive functional decline of HD.
Methods: We performed a multicenter randomized, double-blind, placebo-controlled trial. Patients with early-stage HD (n = 609) were enrolled at 48 sites in the United States, Canada, and Australia from 2008 to 2012. Patients were randomized to receive either CoQ 2,400 mg/d or matching placebo, then followed for 60 months. The primary outcome variable was the change from baseline to month 60 in Total Functional Capacity score (for patients who survived) combined with time to death (for patients who died) analyzed using a joint-rank analysis approach.
Results: An interim analysis for futility revealed a conditional power of <5% for the primary analysis, prompting premature conclusion in July 2014. No statistically significant differences were seen between treatment groups for the primary or secondary outcome measures. CoQ was generally safe and well-tolerated throughout the study.
Conclusions: These data do not justify use of CoQ as a treatment to slow functional decline in HD
Influence of pelvic osteotomy on birth canal size
Six pelvic osteotomies (Salter, Sutherland, Steel, Tönnis, Chiari, and periacetabular) were performed on the right hemipelvis of adult female pelvic plastic models. Each pelvis underwent conventional X-ray and computed tomographic digital pelvimetry before and after osteotomy. The change in the anteroposterior and transverse dimensions at the inlet, midpelvis, and outlet were calculated. None of the osteotomies significantly decreased the inlet. The Salter and Sutherland osteotomies decreased the midpelvis to borderline low. The Salter, Sutherland, and Steel osteotomies significantly decreased the pelvic outlet. These changes correlated closely with those in living patients. Much of this decrease is nullified when the osteotomy is performed prior to the pubertal growth spurt.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47232/1/402_2004_Article_BF00451876.pd
A comprehensive overview of radioguided surgery using gamma detection probe technology
The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology
Definition of antigenic heterogeneity and modulation among human mammary carcinoma cell populations using monoclonal antibodies to tumor-associated antigens.
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