Enhanced hepatic uptake of liposomes through complement activation depending on the size of liposomes

The objective of this study was to differentiate the roles of opsonins and phagocytic cells in the size-dependent hepatic uptake of liposomes in the submicron region. The extent of opsonization decreased with the decrease in size of liposomes (from 800 to 200 nm in diameter) and no enhancement of uptake was observed at 200 nm. There was no effect of liposome size on the uptake of unopsonized liposomes. Serum was pretreated with empty liposomes of each size and its opsonic activity was measured in the perfused liver. The small liposomes could not consume the opsonic activity, while the larger ones did so substantially. These results suggest that opsonins bind to liposomes depending on the size of liposomes and phagocytic cells take up liposomes in proportion to the extent of opsonization. Size-dependent liposome degradation in serum was also found, which was consistent with the size-dependent complement activation, because liposomes with this composition have been shown to be degraded by complement. The mechanism of opsonization was examined by treating serum at 56 degrees C for 30 min or with anti-C3 antiserum. Since both treatments inhibited the opsonic activity, the hepatic uptake of liposomes is considered to occur via complement receptor. In conclusion, the size of liposomes affected complement recognition, and the liposomes were taken up by the liver depending on the extent of opsonization.     

Load mechanics of the wrist

During the last decade, we have been studying load mechanics under a variety of conditions using pressure-sensitive film and, more recently, three-dimensional reconstructions and motion analysis. In all of these studies using pressure-sensitive film, the simulated pathologic or traumatic conditions that were tested showed that all areas in which an increase in contact area or pressure occurred, localized to one area of one joint, coincided with areas in which degenerative changes occurred in the simulated clinical situation. The areas in which there was a decrease or no change in contact area or pressure coincided with areas that were spared from degenerative changes in simulated clinical situations. More recent work has demonstrated that normal carpal kinematics during wrist flexion and extension do not have an instantaneous screw axis that is fixed in or limited to the capitate. These findings change the understanding previously based on studies suggesting that the center of rotation was fixed in the capitate. It was noted that during global wrist motion the radiolunate joint contributes more motion and flexion than the capitolunate joint, but the capitolunate joint contributes more motion and extension than the radiolunate joint. It also was demonstrated that translational motion is a normal component of carpal kinematics.     

Behavior of loose material when using a lobed batch distributor at a blast furnace

The behavior of batch at blast furnaces with different charging devices is studied on the basis of the theory of friable material and experimental data. The nonuniformity of the batch distribution disappears when using a lobed distributor.     

Novel applications of liposomes

Opinions of the usefulness of liposomes in various biotechnological applications range from unsubstantiated optimism to undeserved pessimism. This article reviews the background and development of liposomes, describes products that are commercially available and speculates optimistically about some future applications. The current deepening and widening of interest in liposomes in many scientific disciplines, and their application in medicine, immunology, diagnostics, cosmetics, ecology, cleansing and the food industry are promising novel breakthroughs and products.     

The mechanisms of the lymph-stimulating action of liposomes

The mechanisms of lymph-stimulating action of different liposomes (lecithin-cholesterin, lecithin) were studied in the experiments on dogs. It has been shown an absence of interaction between changes in the lymph outflow rate and system circulation parameters when injecting any liposomes. Moreover, water and protein filtration from the vascular bed into the interstitial space was lowered due to liposomal injection. But oxygen tension in the muscular tissues remained on the level closed to the normal one. In contrast to the intravenous injection, the subcutaneous administration of liposomes has induced the stimulation of lymph outflow, which was more expressed on both volume (nearly by 40%) and duration (nearly by 50%). The experiments with limited and crossed blood flow have demonstrated a regional character of liposomal lymph-stimulating. The mechanisms of such liposomal action may be related to both direct action of liposomes on the lymphatic smooth muscle contractility in the lymphatic vessels and the increased lymph production in the site of liposomal injection due to free radical oxidation processes being limited in that area. The micellar form of phospholipids (essential) has demonstrated no lymph-stimulating action.     

Behavioral Aspects of the Ecocrisis.

This item addresses natural resource depletion and comments that four articles in the American Psychologist's January 1972 edition [APA Task Force on Psychology, Family Planning, and Population Policy (see record 1990-56949-001); R. Buckhout (see record 1972-22841-001); S. H. Newman and M. F. Kelty (see record 1990-56950-001) and M. B. Smith (see record 1972-22844-001)] are heartening evidence of psychology's growing concern with ecology. All of these articles examined the issues of family planning and population density. Briefly, the task is to adjust humans to a world in which there is zero population growth, zero economic growth, and essentially perfect recycling. This author asserts that it would be helpful if APA formally resolved opposition to further growth in population and national product, as well as to reduce its paper consumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hydration of polyethylene glycol-grafted liposomes

In this report we describe the identification, cloning, and expression pattern of human cytokine-like factor 1 (hCLF-1) and the identification and cloning of its murine homologue. They were identified from expressed sequence tags using amino acid sequences from conserved regions of the cytokine type I receptor family. Human CLF-1 and murine CLF-1 shared 96% amino acid identity and significant homology with many cytokine type I receptors. CLF-1 is a secreted protein, suggesting that it is either a soluble subunit within a cytokine receptor complex, like the soluble form of the IL-6R alpha-chain, or a subunit of a multimeric cytokine, e.g., IL-12 p40. The highest levels of hCLF-1 mRNA were observed in lymph node, spleen, thymus, appendix, placenta, stomach, bone marrow, and fetal lung, with constitutive expression of CLF-1 mRNA detected in a human kidney fibroblastic cell line. In fibroblast primary cell cultures, CLF-1 mRNA was up-regulated by TNF-alpha, IL-6, and IFN-gamma. Western blot analysis of recombinant forms of hCLF-1 showed that the protein has the tendency to form covalently linked di- and tetramers. These results suggest that CLF-1 is a novel soluble cytokine receptor subunit or part of a novel cytokine complex, possibly playing a regulatory role in the immune system and during fetal development.     

Studying the mechanics of left ventricular contraction

Actinomycosis of the tongue is a rare form of infection whose initial clinical manifestation is a submucosal swelling that may mimic both benign and malignant neoplasias. Two cases are, presented and their clinical features and diagnostic criteria are discussed in the light of twelve cases drawn from the literature. Infection in the tongue is rare, though perhaps underestimated. It is generally located on the anterior two thirds laterally to the median sulcus, and presents as a moderately painful nodule set deep in the extrinsic and intrinsic muscles and poorly mobile on the adjacent planes. In a few weeks the lesion increases in size and painfulness with consequent loss of function in the absence of diagnosis and appropriate antibiotic management. Both our patients, in fact, presented with deep lesions and no apparent involvement of the mucosa, and were investigated by means of fine-needle aspiration biopsy (FNAB). The aspirated material was used to prepare both routine smears and cell blocks embedded in paraffin. The pathological material provided by this combination of methods proved quantitatively and qualitatively sufficient for the definitive diagnosis of actinomycosis in both cases.     

Effects of protraction mechanics on the midface

A sensitive enantioselective high-performance chromatographic (HPLC) method was developed validated to determine low levels of (-)-R and (+)-S-albuterol in plasma. Baseline resolution was achieved by using a teicoplanin-based chiral stationary phase with a polar organic mobile phase consisting of methanol/ acetonitrile/glacial acetic acid/diethylamine, 40:60:0.3:0.2, (v/v/v/v) and a flow-rate of 1.0 ml/min. Enantioselectivity (alpha) equaled 1.18 and resolution (RS) equaled 1.8. By using fluorescence detection maximized at 230 and 310 nm for excitation and emission, respectively, concentrations of each enantiomer could be measured down to 125 pg/ml from a 1-ml plasma sample. Initially, the method was applied to plasma samples from a small single-dose inhalation study of racemic albuterol in a human volunteer and, later, to in vivo samples from a canine inhalation study of the single enantiomer, (-)-R-albuterol. Results from the canine study showed that no chiral inversion of (-)-R-albuterol occurs in the dog.