Histochemical evaluation of placental dipeptidyl peptidase IV (CD26) in pre-eclampsia: enzyme activity in villous trophoblast indicates an enhanced likelihood of gestational hypertensive disorders

Nitric oxide (NO) acts as a modulator of neuronal transmission in mature neuronal systems, including the retina. Recently, NO has also been suggested to have a trophic function during development. We examined immunocytochemically the distribution of NO-producing cells in developing and transplanted rabbit retinas. An antibody detecting the neuronal isoform of its biosynthetic enzyme, nitric oxide synthase (NOS), was used on normal developing retinas [starting at embryonic day (E) 15] and on rabbit retinal transplants after various survival times (1-139 days after surgery). Weakly stained cell bodies were first observed in the proximal margin of the neuroblastic layer at E 29. Stained processes projecting towards a developing inner plexiform layer were also visible at this time point. Immunoreactive cells were located at later stages in the innermost part of the inner nuclear layer and in the ganglion cell layer, and are likely to correspond mainly to amacrine cells. NOS-labelled cells were also found in retinal transplants. The first NOS-labelled cells appeared, as in normal developing retinas, in ages corresponding to E 29 and were still detected in transplants corresponding to postnatal day 123. NOS-labelled cells were seen in areas between rosettes, where amacrine cells are located. NOS-labelled processes were at times seen to project for long distances, forming very distinct plexuses. NOS-containing amacrine cells thus appear both in the transplants and in developing retinas in the embryonic stages, long before synaptic function involving these cells can be expected, suggesting a role for NO not only in neuromodulation but also in retinal development.     

A Study of Integrated Document and Connection Caching in the WWW

Document caching and connection caching are extensively studied problems. In document caching, one has to maintain caches containing documents accessible in a network. In connection caching, one has to maintain a set of open network connections that handle data transfer. Previous work investigated these two problems separately while in practice the problems occur together: In order to load a document, one has to establish a connection between network nodes if the required connection is not already open. In this paper we present the first study that integrates document and connection caching. We first consider a very basic model in which all documents have the same size and the cost of loading a document or establishing a connection is equal to 1. We present deterministic and randomized online algorithms that achieve nearly optimal competitive ratios unless the size of the connection cache is extremely small. We then consider general settings where documents have varying sizes. We investigate a FAULT model in which the loading cost of a document is 1 as well as a BIT model in which the loading cost is equal to the size of the document.     

A device to measure the cross-sectional area of soft connectivetissues

A device has been designed and fabricated to measure the cross-sectional area of soft connective tissues ex vivo. It consists of two displacement transducers; one sensing tissue thickness and the other sensing width. Outputs are recorded (via an analog to digital interface) using a personal computer. Numerical integration of a thickness versus width plot computes cross-sectional area. This plot also provides a quality check of acquired data. This device has been successfully used in biomechanical studies of rabbit patellar tendons, rat medial collateral ligaments, and dissected specimens of human fascia.     

Vision assistance in scenes with extreme contrast

The performance and architecture of a high dynamic range camera (HDRC) chip and the conceptional advantages for its adaptation to image processing systems in traffic environments are discussed. The HDRC chip was developed with 64×64 pixels using a standard digital 1.2-μm CMOS technology. It is shown that the implementation proves the functionality and indicates the system performance of a highly dynamic range camera is feasible     

Direct and GTP-dependent interaction of ADP ribosylation factor 1 with coatomer subunit beta

A site-directed photocrosslink approach was used to elucidate components that interact directly with ADP- ribosylation factor (ARF)-GTP during coat assembly. Two ARF mutants were generated that contain a photolabile amino acid at positions distant to each other within the ARF molecule. Here we show that one of the two positions specifically interacts with coatomer subunit beta both on Golgi membranes and in isolated coat protein complex type I (COPI)-coated vesicles. Thus, a direct and GTP-dependent interaction of coatomer via beta-coat protein complex (COP) with ARF is involved in the coating of COPI-coated vesicles. These data implicate a bivalent interaction of the complex with the donor membrane during vesicle formation.