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To compare the effectiveness of plasma-derived human thrombin and bovine thrombin for achieving hemostasis during surgery.Adults (N = 305) withor = 1 mild or moderate bleeding site not manageable by conventional modalities during elective cardiovascular, neurologic, or general surgical procedures at multiple study centers were randomized to human (n = 153) or bovine (n = 152) thrombin, applied topically with an absorbable gelatin sponge. Bleeding was assessed 3, 6, and 10 min post-application. Other evaluations included laboratory assessments, vital signs, blood loss, blood transfusions, time in specialty-care units, procedure duration, and length of hospital stay. Blood samples for antibody assessment were collected at baseline and postoperative week 5.The proportion of patients achieving hemostasis within 10 min (primary outcome) was equivalent for human and bovine thrombin (97.4 vs. 97.4%, respectively; ratio, 1.00; 95% CI, 0.96-1.05). The proportions of patients achieving hemostasis at 6 min (94.8 vs. 92.8%) and 3 min (73.2 vs. 72.4%) were also equivalent. No clinically meaningful differences were noted for other variables. The products had similar adverse event profiles. More patients (12.7%) who received bovine thrombin demonstrated seroconversion foror = 1 of the 4 antibodies assayed than patients who received human thrombin (3.3%). No patients in the human thrombin group developed seroconversion for anti-human thrombin or anti-human factor V/Va antibodies. Limitations of this study include the lack of a placebo-control group, the potential for inter-surgeon variability, and the fact that antibody assessment was not evaluable in all patients.Plasma-derived human thrombin and bovine thrombin were equivalent in achieving hemostasis within 10, 6, and 3 min and had comparable safety profiles. None of the patients receiving human thrombin developed seroconversion for antibodies to any of the human antigens.

Noninvasive assessment of heterotopic heart transplants using Doppler echocardiography was first described in two patients by Allen at Stanford in 1981. Since then, numerous experiments studying heterotopic heart transplantation in humans and large animals have confirmed its utility by employing either an intra-abdominal or cervical model. In rats, however, prior research investigating intra-abdominal heterotopic hearts has showed echocardiography to be ineffective. We have recently developed a new technique for heterotopic femoral heart transplantation in rats, which employs the novel use of trans-femoral echocardiography. Therefore, our goal was to re-examine the efficacy of echocardiography for detection of graft rejection. © 2007 Wiley-Liss, Inc. Microsurgery, 2007.

All mechanical heart valves (MHV) are thrombogenic. Application of surface modification technology to reduce the incidence of thrombus formation on MHV is a novel undertaking. This requires collaboration within the bioengineering and cardiothoracic surgery fields. From reviewing results of recent and past investigations, and our own preliminary study with diamond-like carbon coating (DLC) and plasma or glow discharge treatment (GDT) of MHV, we identify and discuss several potentially beneficial effects that may reduce the extent of valve-related thrombogenesis by surface modification. DLC and GDT may affect the surfaces of MHV in many ways, including cleaning of organic and inorganic debris, generating reactive and functional groups on the surface layers without affecting their bulk properties, and making the surfaces more adherent to endothelial cells and albumin and less adherent to platelets. These different effects of surface modification, separately or in combination, may transform the surfaces of MHV to be more thromboresistant in the vascular system.

This work outlines a new way to look at the challenge of coastline security and how to apply existing technology to meet this challenge. With technologies available today, it is quite feasible to implement an undersea fiber optic network and infrastructure that can dramatically increase our ability to detect threats to the security of our coastline from hostile attacks by sea-going vessels. Further, with the scalable network technology described here experts can scan cargo imported into this country for chemical, biological and radiological materials or weapons while that cargo is still at sea. Indeed, we can determine that a threat exists before it becomes an immediate danger. The technologies for deployment, with only modest additional engineering, are available today. However, as important as the application of technology to problem is the shift in mindset that must accompany this approach. Viewing the coastline of this country as a whole, rather than as a series of ports, is critical to securing our coasts.

This ongoing, longitudinal, multi-center, North American study was designed to evaluate the safety and effectiveness of the On-X valve.The On-X valve was implanted in isolated aortic (AVR) and mitral (MVR) valve replacement patients at nine North American centers. Follow up was 98.6% complete. Anticoagulation compliance was evaluated by collection of international normalized ratio (INR) results in all patients throughout their postoperative follow up. Adverse events were recorded according to the AATS/STS guidance criteria. Hematologic studies were conducted postoperatively to evaluate hemodynamics and hemolysis.In total, 142 AVR and 142 MVR implants were performed; the mean follow up was 4.5 years; total follow up was 1,273 patient-years (pt-yr). At implant, the mean patient age was 59.2 years (range: 28 to 85 years); 71.8% of patients who underwent AVR and 33.1% who underwent MVR were males. Preoperatively, 89.4% of AVR patients and 56.3% of MVR patients were in sinus rhythm. The cardiac disease etiology was primarily stenotic, calcific degeneration in AVR and rheumatic or degenerative regurgitation in MVR. Hemolysis represented by postoperative elevation of serum lactate dehydrogenase was very low (median 217 IU after AVR and 251 IU after MVR at one year (82% AVR and 98% MVR of upper normal). Late adverse event rates were low, most notably thromboembolism (0.9%/pt-yr after AVR; 1.6%/pt-yr after MVR) and thrombosis. Kaplan-Meier event-free rates at five years were correspondingly high. Anticoagulation compliance analysis showed only about 40% of INR readings to be within target ranges postoperatively; thus, the control range achieved was much greater than the desired target, as might generally be expected for clinic-controlled INR.The On-X valve performed well in this study, confirming the original design intent of minimal hemolysis and low adverse event rates.

An alternative approach to compute the short and medium load forecasting value using a computational package using fuzzy techniques is shown. The major advantage of this system is its speed, accuracy and flexibility to find the forecasted value. The model utilizes fuzzy techniques to produce a data model for short and medium-term load forecasting studies. The engineer responsible for this activity can also introduce his/her experience before the final forecasting. A user-friendly interface has been developed to provide a man-machine interface. To build this interface, many suggestions from the operators and engineers have been incorporated. This paper also details this interface with all characteristics and features. The Previsor Program has run for more than five years at CEMIG Brazilian State Power Industry.

Several methods exist to establish relations between variables, the most common of which is the construction of models. These models enable the expression of physical relationships or laws between variables. Empirical experimentation, measurement and expert knowledge are alternate means to obtain data and establish said rules. Likewise, many methods have been developed for data representation. Underlying all of these methods are the same two pursuits for the best representation of the data, and the minimum time for execution of the method. The first pursuit seeks the achievement of two goals: a good representation of the data (i.e. minimum error) and a simple formulation (i.e. physically realistic). The second pursuit, a minimum time for execution, is desirable mainly for control processes. There is often however, an inverse relationship between minimum error and time of execution. This paper presents an alternative mathematical tool to yield a data model. The model utilizes fuzzy techniques to produce a data model for short-term load forecasting studies. The engineer responsible for this activity can also introduce his/her experience before the final forecasting. A user friendly interface has been developed to provide a man-machine interface. To build this interface, many suggestions from the operators have been incorporated. This paper also details this interface with all characteristics and features. Currently, this software runs at CEMIG Brazilian State Power Industry. The first impressions of the user are also presented in this paper.

We hypothesized that induction of coagulopathy in sheep would model clinical needle hole and surgical bleeding from synthetic graft anastomoses, and that a new tissue bioadhesive (BioGlue) would control postoperative blood loss during surgical repair of the thoracic aorta.Sheep were anticoagulated with aspirin and heparin. A bypass was made using end-to-side anastomoses of a graft to a partially occluded descending thoracic aorta. Experimental anastomoses (EXP, n = 9) were treated with BioGlue, and control anastomoses (CON, n = 5) were treated with Surgicel to gain intraoperative hemostasis.EXP animals exhibited significantly reduced postsurgical bleeding (CON median 955 mL versus EXP median 470 mL, p0.003), a reduced rate of blood loss over the first 2 postoperative hours (CON median 210 mL/hr versus EXP median 92.5 mL/hr, p0.006), and over the entire recovery period (CON median 158 mL/hr versus EXP median 86 mL/hr, p0.05), and reduced total blood loss (CON mean 1,497 +/- 691 mL versus EXP mean 668 +/- 285 mL, p0.008). On histologic examination of tissues explanted after 3 months, BioGlue was relatively inert and demonstrated a minimal inflammatory response.The use of BioGlue significantly reduced the volume and rate of postsurgical bleeding in a coagulopathic sheep model for thoracic aortic operations. Histopathologically, BioGlue generated only a minimal inflammatory response. This new surgical tissue bioadhesive should prove extremely beneficial for coagulopathic patients undergoing thoracic aortic or vascular procedures.

Surgical repair of aneurysms, traumatic injuries, or congenital anomalies of the thoracic aorta are associated with high morbidity and mortality mainly as a result of excessive and uncontrollable hemorrhage from diffuse coagulopathy. We developed a model in sheep that simulates this coagulopathic state for experimentation with thoracic aorta surgery. This experimental animal model involves administering a 600-mg aspirin suppository once a day for the 2 days preceding surgery and a final dose on-call to surgery. Prior to cross-clamping the aorta, an intravenous (i.v.) bolus of heparin (400 IU/kg) was administered. Thirty minutes later, the i.v. heparin bolus was repeated. Pre- and intraoperative activated clotting time was 101 +/- 10 s and1500 s (p.0001); prothrombin time, 21 +/- 1 s and100 s (p.0001); and activated partial thromboplastin time, 20 +/- 1 s and50 s (p.0001), respectively. We utilized a partial cross-clamp-and-sew technique to anastomose a woven, gelatin-impregnated, 16-mm tube graft end-to-side to the descending thoracic aorta. Mean total blood loss was 1367 +/- 282 mL, which included mean blood loss from time of release of aortic cross-clamp to close (422 +/- 135 mL) and mean total blood output from chest tube drain (945 +/- 203 mL). The mean time to achieve hemostasis at suture lines after aortic cross-clamp release was 15.5 +/- 6.6 min. In conclusion, a sheep model with induced coagulation defects was successfully developed and reproducible for experimentation involving thoracic aortic surgery.

An improved PBS process has been developed and tested for the photomask production. Significant improvements in CD uniformity (3(sigma) < 40 nm over 6' plates) and CD meant- to-target control (< 30 nm) have been achieved through a specially treated puddle development. A low-temperature bake (95 degree(s)C, 30 minutes) was utilized for better linearity while the resolution was 0.5 micrometers for the regular process and as low as 0.35 micrometers for the ghosting process. Defect densities on production plates have been greatly improved to a level lower than our normal production process. The new process is not limited by any specific type of processor, therefore it can be implemented into current production lines easily. It is expected that this new process will meet advanced specs for 256 M DRAM (with 0.25 micrometers design rule) and extend the life of the PBS production line for another 3 - 4 years.

Introduction: In prior studies transplanted peripheral vessels in allogeneic rats had increasing amounts of fibroplasia and hyperplasia with time, associated with chronic rejection. We previously reported on the increased expression of TGF-b2 in a peripheral vessel model. We hypothesized that TGF-b2 expression is linked to expression of Caspace-3 and HSP60 and 70. Methods: Lewis rats served as recipients for femoral artery grafts using Lewis (syngeneic) and Brown-Norway (allogeneic) donors. Vessels were harvested at various times. Each vessel was fixed and immunostained for TGF-b2, Caspace-3, and HSP60 and 70. Image analysis was used to quantify the data. Results were then analyzed using Two Way ANOVA. Results: There was a unique rejection response in the allogeneic transplants, in which initial vessel necrosis is followed by intimal hyperplasia. There was a statistically significant difference among expression of TGF-b2 and Caspace-3 in the allogeneic grafts as compared to the syngeneic grafts. The greatest expression occurred at 25 days in both groups (p < 0.001 for TGF-b2, p = 0.029 for Caspace-3). There was an inverse relationship between TGF-b2 and HSP70 expression over time, with a greater level of HSP70 expression in the syngeneic grafts. There was no significant difference between TGF-b2 expression and HSP60 levels in the two groups, as concentrations of HSP60 remained constant over time. Conclusions: In conclusion, TGF-b2 plays a role in fibroplasia associated with chronic rejection in a peripheral vessel transplant model, possibly related to apoptosis via Caspace-3 expression, and HSP70 expression.

Introduction: Bioengineered human skin constructs (BHSC), comprised of human fibroblasts and keratinocytes on a scaffold of collagen (Alloderm), have been used successfully as an animal alternative in burn research. In order to make the model more representative of human skin, we hypothesized that endothelial cells introduced into the BHSC would form capillary beds. Methods: Human microvascular endothelial cells (HMVEC) were plated onto the BHSC and induced to grow with the addition of growth factors hEGF, hFGF-b, VEGF, IGF and Vitamin C. Samples were fixed at weeks 2 and 3. These samples were stained with H&E and immunostained for the adhesion molecules ICAM and VCAM as well as for the endothelial cell receptor Tie-1. Digital image analysis (DIA) was used to quantify the amount of immunostain within the samples by calculating the average intensity stain index (AISI). Results: Progressive infiltration of HMVEC was noted from weeks one to three. In areas with significant endothelial cell infiltration, capillary formation was dramatic. For the VCAM immunostain, at week 2, AISI was 26.4 and 49.0 at week 3. For Tie-1, AISI was 48.2 at week 2 and 66.8 at week 3. For ICAM, AISI was 48.2 at week 2 and 36.3 at week 3. Conclusions: HMVEC do infiltrate BHSCs and appear to form capillaries. DIA confirmed the marked presence of endothelial cells. The addition of endothelial cells to the burn model greatly enhances the utility and relevance of the BHSC.

1.1.1.2 - Tetrafluoroethane was prepared from isomeric mixtures of dichlorotetrafluoroethanes through selective hydrogenolysis of CF 3 CCl 2 F catalyzed by Pd/C. The other isomer CClF 2 CClF 2 appeared more stable to hydrogenolysis and was only converted partially to the monohydrogenated derivative CHF 2 CClF 2 . The Influences of the three most important operating parameters were defined on the basis of a statistical, testing program. The mathematical elaboration of the experimental data allowed definition of the relationships by which it is possible to foresee conversion of CF 3 CCl 2 F, yield of CF 3 CH 2 F and concentration of reaction products, such as CF 3 CH 3 , CF 3 CH 2 F, CF 3 CHClF and CClF 2 CHF 2 in terms of the above parameters.

1.1.1.2 - Tetrafluoroethane was prepared from isomeric mixture of dichlorotetrafluoroethanes through selective hydrogenolysis of CF 3  CCl 2 F catalyzed by Pd/C. The other isomer CClF 2  CClF 2 appeared more stable to hydrogenolysis and at most it was converted at a low degree to the monohydrogenated derivative CHF 2 CClF 2 . Influence of the three meaningful operating parameters was definided on the basis of a statistical testing program. The mathematical elaboration of the experimental data allowed to define some relations, by which it is possible to foresee conversion of CF 3 CCl 2 F, yield in CF 3 CH 2 F end concentration of reaction products, such as CF 3 CH 3 , CF 3 CH 2 F, CF 3  CHClF end CClF 2 CHF 2 versus the above reported operating parameters.