025Modulation of Wound Repair in the Obese Diabetic Mouse: a Role for VEGF Gene Transfer

Identifying molecular loci of impaired cutaneous healing in diabetes with an eye towards developing targeted therapy to ameliorate dysrepair continues to evolve as a promising area of study. By using an excisional wound model produced on the dorsum of female diabetic C57BL/KsJ db  + / db + mice as well as their normal (WT) & heterozygous (HZ) littermates, we studied the effects of peri‐wound intradermal injection of adeno‐associated viral vector (AAV) expressing the 165‐amino acid isoform of human vascular endothelial growth factor (VEGF) on the following: kinetics of re‐epithelialization, neoangiogenesis and granulation tissue formation, matrix remodelling, collagen deposition, and maturation. One sq. in. full thickness excisional wound was created in the mid‐upper back, rendering half of the wound as either right or left paravertebral. Animals were randomized to receive 1 of 3 treatments via intradermal injection: 1)VEGF (AAV) vector; 2)Adnull vector; 3)PBS. Postoperatively, wounds were examined & photographed on Days 3, 7, 10, 14, 21 & 28. Also, tissue was harvested for histology & immunohistochemistry (PECAM), and snap frozen for protein & RNA analysis. A scoring system was used to grade re‐epithelialization, granulation tissue thickness, matrix density, inflammation, vascular density, epithelial maturity. AAV‐VEGF exerted minimal effect on repair in WT and HZ mice. However, pronounced neovascularization, thickened granulation tissue & increased matrix deposition was noted after VEGF treatment in the db/db mice compared to those that received PBS or adnull vector at all timepoints. While the induction of angiogenesis in VEGF treated db/db mice lagged behind the unimpaired mice by 5–7 days, a global improvement in wound healng was observed.
R Crystal, Dir Inst Genetic Medicine, Weill Med College‐Cornell Univ     

Mitogenic properties of a bispecific single-chain Fv-Ig fusion generated from CD2-specific mAb to distinct epitopes [In Process Citation]

The combination of anti-CD2 mAb 9.6 and 9-1, specific for distinct epitopes, induces proliferation of resting human T cells. The mitogenic activity of this mAb mixture depends upon accessory cells and the 9-1 mAb Fc domain. To further study the functional properties of these mAb, their variable regions were cloned and expressed as monospecific single- chain Fv (scFv) proteins fused to the human IgG1 Fc domain (scFvIg). A novel bispecific scFvIg was constructed by cloning the two monospecific scFv binding sites in tandem, with the 9.6 scFv placed N-terminal to the 9-1 scFvIg. Monospecific scFvIg binding to CD2 was comparable to that of the corresponding parental mAb, while the bispecific scFvIg exhibited binding activity similar to that of the 9-1 scFvIg. The combination of 9.6 scFvIg and 9-1 mAb was mitogenic, whereas mixtures including the 9-1 scFvIg were non-stimulatory, confirming the unique properties of the 9-1 IgG3 Fc. Without the IgG3 tail, the bispecific 9.6/9-1 scFvIg was directly mitogenic and was a more potent mitogen than the mAb mixture, but was accessory cell dependent. Unlike the combination of mAb, the bispecific reagent did not directly mobilize calcium in T cells. In comparison to the mAb mixture, bispecific 9.6/9- 1 scFvIg-mediated stimulation of a mixed lymphocyte reaction was significantly more resistant to inhibition of the CD28 co-stimulatory pathway by the inhibitor CTLA-4-Ig. These results show that expression of the 9.6 and 9-1 binding sites together on a bispecific scFvIg increased the mitogenic properties of the mAb and altered the degree of accessory cell signals required for T cell activation.      

维拉帕米增强博莱霉素A5抗癌活性的机制

本文利用流式细胞术(FCM)和动物整体水平的同位素标记药物示踪方法探讨了维拉帕米(VP)增强博莱霉素A₅(BLM)抗癌活性的机制。实验发现VP显著增强BLM对S-180和HEP-2细胞的G₂期阻断效应。VP改变了⁵⁷Co-BLM在荷瘤小鼠部分器官中的分布,增加厂该药在肿瘤中的积聚。VP增強BLM抗癌活性可能是通过增加药物在肿瘤中的积聚,增强药物的G₂期阻断效应以及其它作用实现的。     

Reoperation for coronary artery disease in the young: early and mid-term results

Background As the incidence of coronary artery disease (CAD) at young age is high in Asian countries, the number of coronary reoperations in this group of patients is increasing. The aim of this study was to define the incidence, risk factors and to discuss the methods of re-revascularization and early to mid-term outcomes in these patients. Methods This study is a retrospective analysis of the data of patients who underwent primary coronary artery bypass surgery (CABG) before the age of 45 years and underwent reoperation for recurrence of angina due to progression of native coronary artery disease and, or, graft occlusion. The data was also analyzed with regards to the risk factors contributing to the recurrence of the disease and the short to mid-term outcomes. During a six year period from January 1998 to October 2004, a total of 68 patients had reoperation for recurrence of angina. The mean interval of presentation following primary CABG was 12.48±3.11 years (ranged from 8 months to 16 years). Reoperation was performed under cardiopulmonary bypass (CPB) in 63 patients and in the remaining five patients on beating heart without using CPB. Results Reoperation accounted for 4.6% of 2478 patients who underwent CABG between January 1998 through October 2004 at our institute. Among these 114 patients, 68 patients underwent primary CABG before the age of 45 years. These 68 patients received a total of 214 grafts (3.14 grafts per patient) of which 169 grafts were re-anastamosed to previously grafted target arteries. Left internal mammary artery was used in 61 patients (89.7%) who required graft to left anterior descending coronary artery at reoperation. The early mortality was 4.4% (3 out of 68). Two patients (2.94%) had perioperative myocardial infarction and two more patients were re-explored for mediastinal bleeding. Freedom from recurrence of symptom of angina at 2 and 4 years was 98.01%, 94.5% respectively. Conclusions Redo CABG is associated with higher morbidity and mortality when compared to first-time CABG. Perioperative myocardial infarction and left ventricular dysfunction contribute significantly to the increased risk of redo CABG.     

Multicentre proton magnetic resonance spectroscopy imaging of primary progressive multiple sclerosis

Multicentre baseline proton magnetic resonance spectroscopic data on primary progressive multiple sclerosis (PPMS) patients are acquired and analysed, using automatic analysis software. The metabolite ratios did not differ from centre to centre. The average N-acetylaspartate/creatine (NAA/Cr) ratio in PPMS was significantly lower compared to normal controls. No significant differences were observed in this ratio between lesion-containing regions (LCR) and normal-appearing tissues (NAT). Strong lipid resonances, even in the absence of lesions, are observed in the both grey and white matter in these patients. These observations suggest extensive diffuse and/or microscopic pathology in PPMS. No significant correlation between any of the metabolite ratios and the Extended Disability Scale Score (EDSS) or with other MR measures such as lesion burden and enhancement volumes is observed.