Knowing where things are parahippocampal involvement in encoding object locations in virtual large-scale space

The availability of a number of new immunosuppressive drugs has resulted in significant improvements in the outcome of kidney transplantation. Currently 1-year graft survival rate for cadaver kidney transplants is approximately 85%. A number of new agents are presently in clinical studies. This article reviews the currently available agents and examines various aspects of induction and maintenance immunosuppressive therapy, and the treatment of acute rejection episodes. In addition, the agents currently in clinical trials and future directions in immunosuppressive therapy are discussed.     

The effect of silica-containing binders on the titanium/face coat reaction

The interactions of CP-Ti and Ti-6Al-4V with investment molds containing alumina/silica and yttria/silica face coat systems were studied. “Containerless” melting in argon was employed and small test samples were made by drop casting into the molds. The effects of the face coat material and mold preheat temperatures on the thickness of the alpha case in the drop castings were evaluated with microhardness and microprobe measurements. It was found that the thickness of the alpha case was the same, whether a yttria/silica or alumina/silica face coat was used, indicating that the silica binder can reduce the apparent inertness of a more stable refractory, such as yttria. It was also found that the alloyed titanium castings had a thinner alpha case than those produced from CP-Ti, which suggests that the thickness of the alpha case depends on the crystal structure of the alloy during cooling from high temperatures. Furthermore, the small drop castings made in small yttria crucibles used as molds exhibited little or no alpha case.     

Glucose and lactate kinetics during a short exercise bout in pregnancy

Recent studies have shown that carotid endarterectomy for significant lesions lowers the risk of stroke and also reduces medical costs by averting the high costs of strokes. However, there has been no information on the cost effect of duplex ultrasound examination which has evolved as the prime means of discovering these carotid lesions. This study reviewed the findings and management of 100 consecutive new patients referred for duplex ultrasound management of the carotid arteries and the cost effects resulting. Seventy-three patients with < 70% stenosis were managed non-operatively; the remaining 27 with 33 lesions producing > 70% stenosis were treated by carotid endarterectomy. It was estimated that 6.5 patients would have had a stroke within 18 months if not operated on. While the medical costs of these strokes would have been $958,838, the cost of avoiding them was $300,494; the result was a significant medical costs saving of $658,344.     

Autologous, hapten-modified vaccine as a treatment for human cancers

PURPOSE: To investigate the cellular dynamics of vessel formation during corneal neovascularization in the living eye by confocal microscopy. METHODS: Corneal neovascularization was initiated by placing a 7-0 silk suture through the corneal stroma 3 mm from the limbus at the 12 o'clock position in both eyes of 10 New Zealand white rabbits. The corneas were examined for vessel ingrowth at intervals from 1 to 15 days after suture placement using a tandem scanning confocal microscope with a 20X water immersion objective, as well as a slit-lamp biomicroscope. Changes in the limbal vessels were recorded on videotape for later analysis. As early vessel growth appeared to be associated with corneal nerves, the total number of sprouts and the number of sprouts along nerves were counted in confocal images, and the results analyzed for statistical significance. Vessel growth and the structural relationship between vascular buds and the deep stromal nerves were examined by light and transmission electron microscopy. RESULTS: The early events of cell migration from the limbal microvessels were found to be associated with the deep stromal nerves; although this association was easily visualized by confocal microscopy, it could not be documented by slit-lamp biomicroscopy. By 18 h after suture placement, the limbal vessels were dilated and the first vascular buds appeared as short, pointed, or flat-topped protrusions from the deep limbal capillaries. By 96 h, the capillary buds had increased in density and had begun to form lumens. Movement of red blood cells was established between 72 and 80 h after the first signs of bud formation, at the same time that cells of immune origin were seen. Confocal microscopy revealed and transmission electron microscopy verified that new bud formation began with the formation of vascular tubes by endothelial migration along the deep stromal nerves. The total number of sprouts and the number of sprouts associated with stromal nerves were similar on days 1 and 2 but differed on days 3-7, suggesting an association between sprouts and nerves in the early stages of neovascularization. CONCLUSION: Using real-time white light confocal microscopy, we were able, for the first time, to observe the process of corneal neovascularization in the living eye, from the earliest stages within hours after initiation to 2 weeks. The deep stromal nerves appear to serve as a focus for the growth of new vessels, by attracting and supporting vessel growth and/or by providing a potential space for movement of the endothelial cells. Confocal microscopy may provide a new approach to achieving a better understanding of the mechanisms involved in corneal neovascularization.     

Long-term survival of segmental pancreas isografts in NOD/Lt mice treated with anti-CD4 and anti-CD8 monoclonal antibodies

Spontaneously diabetic nonobese diabetic (NOD/Lt) mice were treated with anti-T-cell monoclonal antibodies (mAbs) at the time of grafting with vascularized segmental pancreas isografts. Recipients were either untreated or given anti-CD4 and/or anti-CD8 mAbs (0.5 mg/20-g mouse on each of 4 consecutive days), which reduced target cell levels to <5% of normal. Graft function was monitored by measuring blood glucose (BG) levels. Transplants were removed for histological examination when BG returned to >20 mmol/l for two consecutive readings. Isografts from 3- to 4-week-old prediabetic mice placed in untreated diabetic NOD mice ceased functioning in 9-13 days with a mean survival time (MST) +/- SD of 10 +/- 2. Treatment with anti-CD4 prolonged survival significantly (MST = 61 +/- 35 days, P < 0.05 compared with untreated control mice). Anti-CD8 treatment was less effective, but it still significantly improved graft survival (MST = 24 +/- 9 days, P < 0.05 compared with untreated control mice). Anti-CD8 plus anti-CD4 treatment was highly effective in inhibiting autoimmune destruction of the grafts (MST = 97 +/- 8 days). This clearly demonstrates that transient inactivation of most T-cells with anti-CD4 plus anti-CD8 mAbs effectively controls autoimmune disease in the isograft, despite recovery of CD4 and CD8 T-cells to normal levels. Although insulitis developed in the long-term grafts, insulitis scores did not increase between 33 and 100 days, and none of the mice progressed to IDDM in 100 days. Histology showed a predominantly peri-islet T-cell and macrophage infiltrate with ductal expression of the cytokines interleukin (IL)-4, IL-2, and interferon-gamma. There was little infiltrate or expression of cytokines within the islets. Thus, mAb treatment at the time of grafting allowed isograft survival and prevented progression from insulitis to beta-cell destruction.     

Cover Feature: A Comparative Study of in vitro Assays for Predicting the Nonspecific Binding of PET Imaging Agents in vivo (ChemMedChem 7/2020)

Nonspecific binding (NSB) is a key parameter in optimizing PET imaging tracers. We compared the ability to predict NSB of three available methods: LIMBA, rat f_u,brain, and CHI(IAM). Even though NSB is often associated with lipophilicity, we observed that logD does not correlate with any of these assays, clearly indicating that lipophilicity, while influencing NSB, is insufficient to predict it. A cross-comparison of the methods showed that all three correlate and are useful predictors of NSB. The three assays, however, rank the molecules slightly differently, illustrating the challenge of comparing molecules within a narrow chemical space. We also noted that CHI(IAM) values more effectively predict V_NS, a measure of in vivo NSB in the human brain. CHI(IAM) measurements might be a closer model of the actual physicochemical interaction between PET tracer candidates and cell membranes, and seems to be the method of choice for the optimization of in vivo NSB.     

High degree of N-functionalization in macroscopically assembled carbon nanotubes

Journal of Materials Science - Nitrogen doping of carbon nanomaterials has emerged as a method to develop novel material properties, though limitations in the form of extended treatment times,...     

Evaluation of layout and atmospheric stability effects in wind farms using large‐eddy simulation

Large‐eddy simulation (LES) has been used previously to study the effect of either configuration or atmospheric stability on the power generated by large wind farms. This is the first study to consider both stability and wind farm configuration simultaneously and methodically with LES. Two prevailing wind directions, two layouts (turbines aligned versus staggered with respect to the wind) and three stabilities (neutral and moderately unstable and stable) were evaluated. Compared with neutral conditions, unstable conditions led to reduced wake losses in one configuration, to enhanced wake losses in two and to unchanged wake losses in one configuration. Conversely, stable conditions led to increased wake losses in one, decreased wake losses in two and unchanged wake losses in one configuration. Three competing effects, namely, rates of wake recovery due to vertical mixing, horizontal spread of wakes and localized regions of acceleration caused by multiple upstream wakes, were identified as being responsible for the observed trends in wake losses. The detailed flow features responsible for these non‐linear interactions could only be resolved by the LES. Existing analytical models ignore stability and non‐linear configuration effects, which therefore need to be incorporated. Copyright © 2017 John Wiley & Sons, Ltd.     

Thickness dependent electronic structure of ultra-thin tetrahedral amorphous carbon (ta-C) films

Microstructural properties of ultrathin (1-10 nm) tetrahedral amorphous carbon (ta-C) films are investigated by Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy, X-ray Photoelectron Spectroscopy, Raman spectroscopy and Atomic Force Microscopy (AFM). The CK-edge NEXAFS spectra of 1 nm ta-C films provided evidence of surface defects (C―H bonds) which rapidly diminish with increasing film thickness. A critical thickness for stabilization of largely sp³ matrix structure distorted by sp² sites is observed via the change of π*C═C peak behavior. Meanwhile, an increase in the film thickness promotes an enhancement in sp³ content, the film roughness remains nearly constant as probed by spectroscopic techniques and AFM, respectively. The effect of thickness on local bonding states of ultrathin ta-C films proves to be the limiting factor for their potential use in magnetic and optical storage devices.     

Using maintenance rehearsal to explore recognition memory.

We examined associative and item recognition using the maintenance rehearsal paradigm. Our intent was to control for mnemonic strategies; to produce a low, graded level of learning; and to provide evidence of the role of attention in long-term memory. An advantage for low-frequency words emerged in both associative and item recognition at very low levels of learning. This early emergence casts doubt on explanations based on the traditional concept of recollection. A comparison of false alarms supports a role for item information or the joint use of cues but not familiarity in producing associative false alarms. We may also have found a way to measure the amount of attention being paid to a to-be-learned item or pair, independently of memory performance on the attended item. This result may be an important step in determining whether coherent theories about the role of attention in long- and short-term memory can be created. (PsycINFO Database Record (c) 2010 APA, all rights reserved)