Evaluation of monoclonal antifibrin antibodies by their binding to human blood clots

The primary goal of this study was to develop a method for evaluating fibrin-specific antibodies as thrombus detecting agents. The apparatus and assay conditions were chosen by testing antibody 64C5, which binds to the amino terminus of the fibrin beta chain, for its ability to bind to human blood clots. Using 125I-labeled antibody 64C5, the effects of antibody concentration, clot shape, clot mass, temperature, and flow rate were tested. Increased antibody binding was observed when antibody concentration, clot mass and temperature were increased. Under one set of conditions, six 125I-labeled monoclonal antifibrin antibodies (four specific for the beta chain, two specific for the alpha chain) were tested for their binding to retracted clots of human blood. Two radioiodinated antidigoxin antibodies were used as a control. Beta chain-specific antibody 59D8, which provided the highest level of binding to clot, bound 14-fold better than the control antidigoxin antibody. Neither alpha chain-specific antibody bound to clotted blood. To examine the in vivo relevance of the in vitro binding to clots, the uptake of antibody 64C5 was assessed for its binding to human fibrin clotted within the jugular vein of a rabbit. The correlation coefficient between in vitro and in vivo uptake as a function of clot weight was calculated to be 0.91. Thus, in vitro binding of monoclonal antifibrin antibodies to human blood clots was judged to be a realistic method for the comparison and selection of an ideal antifibrin antibody for detailed in vivo testing.     

Cardiovascular influence of dental anxiety during local anesthesia for tooth extraction.

OBJECTIVE: The present study evaluated whether dental patient anxiety has an effect on the cardiovascular response to the delivery of anesthetic to achieve mandibular anesthesia. STUDY DESIGN: One hundred eighty adult patients scheduled to receive routine dental extraction under local anesthesia were enrolled in this prospective study. Anxiety was measured at 15 minutes before local anesthetic delivery using Corah's Dental Anxiety Scale (Corah's DAS). Anesthetic was delivered using a standard technique for mandibular nerve block with the same dose (2 cartridges) given to all patients. Cardiovascular response data including blood pressure, heart rate, O(2) saturation, and electrocardiographic changes were measured at 5 time points from 5 minutes before to 15 minutes after the administration of anesthetic. RESULTS: The mean anxiety scale score before administration of anesthetic was 9.3 (SD +/- 2.5) with a range from 4 to 20. Women had a significantly higher mean dental anxiety level than men (P < .05). Younger age was associated with a higher anxiety scale score. Severe preoperative anxiety (Corah's DAS >12) was associated with significantly increased heart rate during administration of anesthetic. Patients with severe anxiety also had a significantly greater increase in heart rate during anesthetic administration (P < .001). Younger age was associated with increased likelihood of high dental anxiety and associated cardiovascular response to dental anesthesia (P = .001). Pain on injection was also associated with increased heart rate during anesthetic administration. CONCLUSION: This study showed that Corah's dental anxiety scale is a useful tool for estimating the impact of anxiety on the heart rate during local anesthetic delivery to achieve mandibular block for dental extraction. Younger patients undergoing tooth extraction were more likely to have high anxiety levels, and younger patients with high anxiety were more likely to report a traumatic dental history. High anxiety, younger age, and traumatic dental history were correlated with greater increases in heart rate during the administration of local dental anesthesia.     

Sonographically guided antegrade common femoral artery access.

OBJECTIVE: To evaluate the feasibility of sonographically guided antegrade common femoral artery puncture and superficial femoral artery access. METHODS: Fifty antegrade common femoral artery punctures and superficial femoral artery access procedures were performed under sonographic guidance alone in 30 consecutive patients (24 male and 6 female; mean age, 55.1 +/- 25.7 years; range, 13-85 years). The indications were (1) insertion of a vascular sheath for balloon angioplasty in 42 attempts (24 patients with lower leg ischemia) and (2) insertion of an angiographic catheter for 1-shot intra-arterial chemoinfusion therapy in 8 attempts (6 patients with distal femoral osteosarcomas). RESULTS: Technical success was achieved in 28 of 30 patients or 48 (96%) of 50 procedures (95% confidence interval, 80.39-98.32). The average procedure time +/- SD (excluding the failures) was 3 +/- 1 minutes (range, 2-6 minutes). In the 2 failures (2 [4%] of 50) in which common femoral artery punctures were accomplished, further superficial femoral artery cannulations were completed under fluoroscopic road map angiographic guidance. A small groin hematoma was noted in 1 patient. No arteriovenous fistula or pseudoaneurysm was encountered. CONCLUSIONS: Sonographically guided antegrade common femoral artery puncture and selective cannulation of the superficial femoral artery are feasible and safe. They may be used as adjunctive modalities in difficult cases of common femoral artery access.     

Efficacy and safety of barnidipine compared with felodipine in the treatment of hypertension in Chinese patients

The efficacy and safety profiles of barnidipine in the treatment of hypertension were evaluated in an open parallel-group study. Fifty-nine Chinese patients with mild-to-moderate essential hypertension were randomized to receive either barnidipine or felodipine (5 mg once daily, titrated to 10 mg or 15 mg once daily, as indicated) for 12 weeks. Both drugs reduced blood pressures significantly with > or = 68% of cases obtaining marked or moderate blood pressure reduction. Mean reductions in systolic and diastolic blood pressure for barnidipine treatment were 23.7 +/- 13.5 mmHg and 12.7 +/- 7.9 mmHg, and for felodipine, 24.3 +/- 18.4 mmHg and 14.5 +/- 10.0 mmHg, respectively. There was no significant difference between these two drugs in anti-hypertensive effect, heart rate, laboratory measurements or incidence of adverse events. The only difference was that more patients taking felodipine experienced palpitations. We conclude that barnidipine has similar efficacy and a similar safety profile to felodipine in the treatment of mild-to-moderate essential hypertension in Chinese patients.     

Chemotherapy using 5-fluorouracil,mitoxantrone, and cisplatin for patients with advanced hepatocellular carcinoma: an analysis of 63 cases

Background We evaluated the anti-tumor efficacy and toxicity of 5-fluorouracil (5-FU), mitoxantrone, and cisplatin (FMP) in patients with advanced hepatocellular carcinoma (HCC), and conducted an analysis of the prognostic factors for response to such therapy and patient survival.Methods Sixty-three patients suffering from unresectable and non-embolizable HCC and who had objectively measurable tumors, adequate liver and renal function, and adequate bone-marrow reserve were enrolled in this study. The therapeutic regimen consisted of cisplatin 80mg/m² and mitoxantrone 6mg/m² intravenously on day 1, and 5-FU 450mg/m² per day continuous infusion for a period of 5 days. Univariate and multivariate analyses of patient and disease characteristics were used to identify factors predicting patient response and survival.Results The objective response was 23.8% (95% confidence interval [CI], 13.0–34.6%). The median survival for all 63 patients was 4.9 months (95% CI, 3.2–6.6 months). The median time to progression was 2.5 months (95% CI, 1.7–3.3 months). Multivariate analysis identified only performance status (P = 0.050) and liver tumor size (P = 0.012) as being significantly related to patient objective response. Independent variables associated with a better patient survival included: the absence of ascites (P = 0.003), a lower total bilirubin level (P = 0.026), and the patient being a positive chemotherapy responder (P = 0.009).Conclusions The response rate to an FMP regimen was still unsatisfactory, although a specific subgroup of patients (good performance status, smaller liver tumor mass, good liver reserve, and distant metastasis) may benefit from this regimen.     

Enhanced gene transfer to rabbit jugular veins by an adenovirus containing a cyclic RGD motif in the HI loop of the fiber knob.

Gene therapy using recombinant adenoviral vectors represents a promising therapeutic tool to prevent vein graft stenosis, the main complication of coronary artery bypass grafting. However, the low transduction efficiency of vascular smooth muscle cells and endothelial cells (EC) is a potential limitation, presumably due to the low levels of functional adenovirus receptor (coxsackie:adenovirus receptor; CAR). Designing vectors specifically targeted to alpha(v) integrins is a strategy that might overcome the poor expression of CAR in vascular smooth muscle cells and EC. RGD, a receptor-binding motif that can interact with alpha(v) integrins, was inserted into the HI loop and at the C-terminus of the adenoviral fiber protein in two separate adenovirus vectors encoding a beta-galactosidase reporter gene. Av1nBgCRGD (C-terminus) and Av1nBgHIRGD (HI loop) were evaluated in EC in culture and in jugular vein organ culture. Transduction of primary rat and rabbit EC with Av1nBgHIRGD was significantly more efficient when compared to Av1nBgCRGD or Av1nBg. Transduction of mouse, rat and rabbit jugular veins in organ culture using Av1nBg showed that adenovirus-mediated gene expression was greatest in rabbit jugular veins compared to rat and mouse veins. Av1nBgHIRGD augmented gene expression approximately four-fold in rabbit jugular veins when compared to Av1nBg. Histochemical analysis showed that numerous EC but few smooth muscle cells were transduced at all vector concentrations. A substantial number of adventitial fibroblasts were transduced only at the highest vector concentrations of Av1nBgHIRGD. These findings demonstrate that integrin-targeted vectors allow for enhanced gene delivery to veins and strengthen the viability of adenoviral-mediated gene transfer of therapeutic transgenes to human veins prior to vein grafting.     

Pluripotent stem cell-derived cardiac tissue patch with advanced structure and function

Recent advances in pluripotent stem cell research have provided investigators with potent sources of cardiogenic cells. However, tissue engineering methodologies to assemble cardiac progenitors into aligned, 3-dimensional (3D) myocardial tissues capable of physiologically relevant electrical conduction and force generation are lacking. In this study, we introduced 3D cell alignment cues in a fibrin-based hydrogel matrix to engineer highly functional cardiac tissues from genetically purified mouse embryonic stem cell-derived cardiomyocytes (CMs) and cardiovascular progenitors (CVPs). Procedures for CM and CVP derivation, purification, and functional differentiation in monolayer cultures were first optimized to yield robust intercellular coupling and maximize velocity of action potential propagation. A versatile soft-lithography technique was then applied to reproducibly fabricate engineered cardiac tissues with controllable size and 3D architecture. While purified CMs assembled into a functional 3D syncytium only when supplemented with supporting non-myocytes, purified CVPs differentiated into cardiomyocytes, smooth muscle, and endothelial cells, and autonomously supported the formation of functional cardiac tissues. After a total culture time similar to period of mouse embryonic development (21 days), the engineered cardiac tissues exhibited unprecedented levels of 3D organization and functional differentiation characteristic of native neonatal myocardium, including: 1) dense, uniformly aligned, highly differentiated and electromechanically coupled cardiomyocytes, 2) rapid action potential conduction with velocities between 22 and 25 cm/s, and 3) significant contractile forces of up to 2 mN. These results represent an important advancement in stem cell-based cardiac tissue engineering and provide the foundation for exploiting the exciting progress in pluripotent stem cell research in the future tissue engineering therapies for heart disease.     

Flap pedicle vena comitant as a vein graft donor source

A vena comitant segment harvested from a flap's pedicle can be used as an interpositional vein graft in selected microvascular cases. When a vascular pedicle includes paired venae comitantes, one of these can prove suitable for use as a vein graft while still allowing for venous outflow of the flap. An additional operative site and procedure to harvest a vein graft can be avoided if a vena comitant segment can be used. We present eight cases in which pedicle vena comitant segments were used as interpositional vein grafts. In six cases, vena comitant grafts were used to supercharge or augment venous outflow in transverse rectus abdominis myocutaneous (TRAM) flaps used for breast reconstruction. A vena comitant graft was used to revise the venous anastomosis in one deep inferior epigastric perforator (DIEP) flap. The arterial anastomosis was revised with a vena comitant graft in a gracilis muscle free flap. Our experience demonstrates the viability and utility of using the flap pedicle's vena comitant as a source of vein graft in selected cases.