No abstract

To investigate the clinical manifestations of Aspergillus infections in lung transplant recipients, we reviewed the mycology and autopsy reports of all double (DLT=93) and single (SLT=48) lung transplant recipients from November 1983 to May 1993. Positive Aspergillus cultures were identified in 22% of the recipients (DLT=21, SLT=10). Colonization alone was present in 19 recipients (DLT=16, SLT=3). Complicated Aspergillus infection included Aspergillus bronchitis (DLT=1, SLT=1), aspergilloma (SLT=2), pulmonary invasive aspergillosis (DLT=1, SLT=2), disseminated aspergillosis (DLT=1, SLT=2), empyema (DLT=1), and a retroperitoneal abscess (DLT=1). Symptoms were seen only in patients with complicated lung infections and CXR abnormalities began in the native lung of four SLT recipients. Twenty patients survived (DLT=17, SLT=3) and 11 died (DLT=4, SLT=7) of disseminated aspergillosis (SLT=2), pulmonary invasive disease (DLT=1), bronchiolitis obliterans (DLT=2, SLT=2, CMV pneumonitis (SLT=1), diffuse alveolar damage (SLT=2), and hyperacute rejection (DLT=1). Complicated infection and mortality were more common in SLTs than DLTs (P<0.05). We conclude that infection with Aspergillus is not infrequent in the lung transplantation population. Single lung recipients develop more complicated infection than double lung recipients after Aspergillus infection with native lung being a potential source of infection.

LECSIM is a highly efficient logic simulator which integrates the advantages of event driven interpretive simulation and levelized compiled simulation. Two techniques contribute to the high efficiency. First it employs the zerodelay simulation model with levelized event scheduling to eliminate most unnecessary evaluations. Second, it compiles the central event scheduler into simple local scheduling segments which reduces the overhead of event scheduling.Experimental results show that LECSIM runs about 8-77 time faster than traditional unit-delay event-driven interpretive simulator. LECSIM also provides the option of scheduling with respect to individual gates or with respect to fan-out free blocks. When the circuit is partitioned into fan-out free blocks, the speed increases by a factor of 2-3. With partitioning, the speed of LECSIM is only about 1.5-3.4 times slower than a levelized compiled simulation for the combinational circuits we have tested.

The plasma pharmacokinetics of benazepril and its active metabolite, benazeprilat, were determined in cats after oral administration of benazepril.HCl at dosages of 0.25, 0.5 and 1.0 mg/kg as a single dose (n = 5 per group) and after once daily application for 8 days (n = 6 per group). Pharmacodynamics were assessed by measurement of plasma angiotensin converting enzyme (ACE) activity. After single administration of benazepril.HCl, maximum benazepril concentrations were recorded at the first sample (2 h) and declined relatively rapidly with an elimination half life (t1/2) of 1.4 h. Highest benazeprilat concentrations were recorded at the first sample (2 h) in most cats and declined biphasically with half lives of each phase of 2.4 and 27.7 h. With repeated administration, plasma benazeprilat concentrations accumulated slightly with accumulation ratios (R) of 1.46, 1.36 and 1.24 for the 0.25, 0.5 and 1.0 mg/kg dosages of benazepril.HCl, respectively (median value of 1.36 for all dosages). All three dosages of benazepril.HCl caused marked inhibition of plasma ACE activity in all cats. The maximum effect (Emax, % inhibition of ACE as compared to baseline) was > or = 98% after single and 100% with repeated administration. The duration of action of benazepril.HCl was long, with > 87% (single) and > 90% (repeat) inhibition of plasma ACE persisting 24 h after dosing. Benazepril.HCl was well tolerated in all animals. Dosages of 0.25-1.0 mg/kg benazepril.HCl once daily are recommended for clinical testing in cats.

Registration of a preoperative CT (3D) image to one or more X-ray projection (2D) images, a special case of the pose estimation problem, has been attempted in a variety of ways with varying degrees of success. Recently, there has been a great deal of interest in intensity-based methods. One of the drawbacks to such methods is the need to create digitally reconstructed radiographs (DRRs) at each step of the optimization process. DRRs are typically generated by ray casting, an operation that requires Ç´Ò ¿ µ time, where we assume that Ò is approximately the size (in voxels) of one side of the DRR as well as one side of the CT volume. We address this issue by extending light field rendering techniques from the computer graphics community to generate DRRs instead of conventional rendered images. Using light fields allows most of the computation to be performed in a preprocessing step; after this precomputation, very accurate DRRs can be generated in Ç´Ò ¾ µ time. Another important issue for 2D-3D registration algorithms is validation. Previously reported 2D-3D registration algorithms were validated using synthetic data or phantoms but not clinical data. We present an intensity-based 2D-3D registration system that generates DRRs using light fields; we validate its performance using clinical data with a known gold standard transformation.