Role of Macrophages and RhoA Pathway in Atherosclerosis

The development, progression, or stabilization of the atherosclerotic plaque depends on the pro-inflammatory and anti-inflammatory macrophages. The influx of the macrophages and the regulation of macrophage phenotype, inflammatory or anti-inflammatory, are controlled by the small GTPase RhoA and its downstream effectors. Therefore, macrophages and the components of the RhoA pathway are attractive targets for anti-atherosclerotic therapies, which would inhibit macrophage influx and inflammatory phenotype, maintain an anti-inflammatory environment, and promote tissue remodeling and repair. Here, we discuss the recent findings on the role of macrophages and RhoA pathway in the atherosclerotic plaque formation and resolution and the novel therapeutic approaches.     

Off-axis cross-polarization and polarization efficiencies of reflector antennas

Cross polarization in reflector antennas is related to the polarization efficiency. Simple approximate expressions for the peak cross polarization are derived in terms of the polarization efficiency. Front-fed, Cassegrainian, and offset antennas are considered. It is shown that symmetrical antennas have lower peak sidelobes than offset antennas with the same polarization efficiency by approximately 2.5 dB. Excellent agreement between the present method and other methods is achieved. Formulas for the off-axis angle at which peak cross polarization takes place are also given for symmetrical and offset reflectors. It is found that for reflectors with the sameD/lambdaratio, symmetrical antennas have larger off-axis angles (1.6 times larger) for peak cross polarization in comparison with offset antennas.     

Crosspolarisation in Cassegrain and front-fed antennas

The superior off-axis crosspolarisation performance of Cassegrain antennas, compared with that of front-fed antennas, is emphasised for conventional primary feeds. This statement is supported by theory and by measurements on both configurations.     

Compiling C for the EARTH multithreaded architecture

Multithreaded architectures provide an opportunity for efficiently executing programs with irregular parallelism and/or irregular locality. This paper presents a strategy that makes use of the multithreaded execution model without exposing multithreading to the programmer. Our approach is to design simple extensions to C, and to provide compiler support that automatically translates high-level C programs into lower-level threaded programs. In this paper we present EARTH-C our extended C language which contains simple constructs for specifying control parallelism, data locality, shared variables and atomic operations. Based on EARTH-C, we describe compiler techniques that are used for translating to lower-level Threaded-C programs for the EARTH multithreaded architecture. We demonstrate our approach with six benchmark programs. We show that even naive EARTH-C programs can lead to reasonable performance, and that more advanced EARTH-C programs can give performance very close to hand-coded threated-C programs. This work supported, in part, by NSERC and FCAR.     

Liver transplantation for decompensated cirrhosis after jejunoileal bypass: a strategy for management

BACKGROUND: Although jejunoileal bypass results in end-stage liver disease in up to 100% of patients, little is known about outcome after liver transplantation. METHODS: The clinical courses of six patients who underwent liver transplantation at UCLA for decompensated cirrhosis owing to a jejunoileal bypass were reviewed. Liver function, allograft pathology, renal function, and nutritional status were assessed. RESULTS: Of the four patients with an intact jejunoileal bypass, two of the three who were biopsied had recurrent steatotic liver disease. The two patients whose jejunoileal bypass was reversed at the time of liver transplantation had lower alkaline phosphatase, lower creatinine, higher albumin, and higher cholesterol, and were more obese than their counterparts with intact bypasses. CONCLUSIONS: Patients undergoing liver transplantation for jejunoileal bypass-associated liver disease should, if possible, have their bypass reversed at the time of transplantation; otherwise, they must be followed closely and be biopsied routinely. Recurrent liver disease should prompt reversal of the jejunoileal bypass.     

Mutual interference between linear crosspolarised radio channels at 11 GHz

Preliminary findings are presented from a study to determine the mutual interference between linear crosspolarised radio channels at 11 GHz over an 8?-mile path. In particular, severe crosspolarising effects were encountered when antenna primary-feed apertures were artificially wetted or allowed to become wet during rain and snow. Significantly improved values of isolation between channels have been measured under heavy rainfall with the antennas protected from rain.     

Axial cross polarization in reflector antennas with surface errors of large correlation diameter

Equations for boresight cross polarization and isolation of axisymmetric and offset antennas in the presence of surface errors are derived in terms of numerically computable integrals. Computations revealed that 1) for root mean square (rms) error< lambda/4cross polarization increases monotonically with increasing rms error; and 2) maximum cross polarization occurs when the correlation diameter is 0.5Dfor axisymmetric antennas (0.8Dfor offset antennas). For rms error>lambda/4boresight cross polarization remains almost constant. Furthermore, results revealed that for given correlation diameter and rms error, axisymmetric antennas offer better boresight isolation in comparison with offset antennas having the same polarization efficiency.     

Long-term survival after retransplantation of the liver

OBJECTIVE: The authors determined the long-term outcome of patients undergoing hepatic retransplantation at their institution. Donor, operative, and recipient factors impacting on outcome as well as parameters of patient resource utilization were examined. SUMMARY BACKGROUND DATA: Hepatic retransplantation provides the only available option for liver transplant recipients in whom an existing graft has failed. However, such patients are known to exhibit patient and graft survival after retransplantation that is inferior to that expected using the same organs in naiive recipients. The critical shortage of donor organs and resultant prolonged patient waiting periods before transplantation prompted the authors to evaluate the results of a liberal policy of retransplantation and to examine the factors contributing to the inferior outcome observed in retransplanted patients. METHODS: A total of 2053 liver transplants were performed at the UCLA Medical Center during a 13-year period from February 1, 1984, to October 1, 1996. A total of 356 retransplants were performed in 299 patients (retransplant rate = 17%). Multivariate regression analysis was performed to identify variables associated with survival. Additionally, a case-control comparison was performed between the last 150 retransplanted patients and 150 primarily transplanted patients who were matched for age and United Network of Organ Sharing (UNOS) status. Differences between these groups in donor, operative, and recipient variables were studied for their correlation with patient survival. Days of hospital and intensive care unit stay, and hospital charges incurred during the transplant admissions were compared for retransplanted patients and control patients. RESULTS: Survival of retransplanted patients at 1, 5, and 10 years was 62%, 47%, and 45%, respectively. This survival is significantly less than that seen in patients undergoing primary hepatic transplantation at the authors' center during the same period (83%, 74%, and 68%). A number of variables proved to have a significant impact on outcome including recipient age group, interval to retransplantation, total number of grafts, and recipient UNOS status. Recipient primary diagnosis, cause for retransplantation, and whether the patient was retransplanted before or after June 1, 1992, did not reach statistical significance as factors influencing survival. In the case-control comparison, the authors found that of the more than 25 variables studied, only preoperative ventilator status showed both a significant difference between control patients and retransplanted patients and also was a factor predictive of survival in retransplanted patients. Retransplant patients had significantly longer hospital and intensive care unit stays and accumulated total hospitalization charges more than 170% of those by control patients. CONCLUSIONS: Hepatic retransplantation, although life-saving in almost 50% of patients with a failing liver allograft, is costly and uses scarce donor organs inefficiently. The data presented define patient characteristics and preoperative variables that impact patient outcome and should assist in the rational application of retransplantation.