Litomosoides carinii: extraction of the microfilarial sheath components and antigenicity of the sheath fractions

Microfilarial sheaths ofLitomosoides carinii were isolated and extracted with 2% sodium dodecyl sulfate (SDS) and 5% 2-mercaptoethanol (2ME). Extraction with SDS alone did not alter the ultrastructure of the sheaths and yielded five polypeptides (27–67 kDa) that were not recognized by antibodies of infected hosts but reacted with antibodies to host-serum proteins. 2ME treatment caused partial solubilization of the sheaths (45% as determined by amino acid analysis), which could be further improved by combining 2ME with SDS. The remainder showed filamentous/threadlike structures on electron microscopic examination. As compared with whole sheaths, the insoluble proportion was markedly enriched in alanine and cysteine but contained less galactosamine, serine, and threonine. SDS-polyacrylamide gel electrophoresis (SDS-PAGE) of 2ME/SDS-extractable components showed 12–16 bands of 14>120 kDa. A predominant component had an apparent molecular mass of 22 kDa. Two bands (42 and 120 kDa) could be stained with Coomassie blue but showed negative staining when gels were stained with silver. Several components (but not the 22-kDa polypeptide) bore phosphocholine epitopes. Apart from the negatively staining bands, most of the 2ME-soluble sheath components were recognized by antibodies ofL. carinii-infectedMastomys coucha. Except for several polypeptides that had been unspecifically recognized by IgM, the antibody response to sheath components started at the end of the prepatent period.This work was supported by the Deutsche Forschungsgemeinschaft (Sonderforschungsbereich 272)     

Creatine kinase isoenzyme (CK-BB) in combination to prostatic acid phosphatase measured by RIA in the diagnosis of prostatic cancer

Summary Creatine kinase isoenzyme (CK-BB) measured by mass was used to determine its value in the early diagnosis of prostatic cancer. Sera of patients with prostatic carcinoma of various stages (treated and untreated) were compared to normal male sera and sera of patients with benign hyperplasia of the prostate (BPH) with respect to CK-BB. The sera were simultaneously tested for PAP content. The sensitivity of the CK-BB-RIA was 1.63+/-0.08 g/l and reproducibility in the higher and lower concentration range 7.6% and 10.5%, respectively. CK-BB alone or in combination with PAP is no marker for early detection of prostatic cancer. In individual cases changes occurred similar to those found with a malignant growth of the prostate.     

Silicone rubber-- an unsuitable and dangerous material for T-drains]

Four cases of bile peritonitis after removal of silastic T-tubes are described. The removal of the tubes took place 8 to 23 days after operation. This complication has been described only since the introduction of silastic tubing. The therapy consists in early relaparotomy and drainage. In dogs, the behavior of intraperitoneal silastic and rubber tubes was compared. Whereas rubber tubing was completely surrounded by a fibrous sheet not later than 2 weeks after implantation, the silastic tubing was floating freely in the abdominal cavity even after 6 weeks. Therefore, the use of silastic tubes is dangerous in short-time bile duct drainage. On the other hand, this material had advantages for long-term drainage and for endoluminal prostheses.     

(5) Feminist theory and pharmacy practice

This is the fifth in a series of articles highlighting the relevance of sociological theory to pharmacy practice research. The article provides an introduction to feminist theory and research as applied to health, illness and health care. The aim is to clarify the contribution made by feminist theory in developing useful conceptual tools and theories in two major areas: the specific experiences of women's health and understanding the role of women as providers of health care. We seek to contribute to a research agenda, informed by feminist thinking, for pharmacy practice. The focus of this article is on feminist theory as developed in the West, with particular emphasis on issues of concern for pharmacy practice research. We begin with a discussion of the historical context of feminism, including the women's movement and the women and health movement. This is followed by an overview of selected feminist theories. Feminist perspectives on the experience of health and illness are discussed in more detail, including issues of reproductive technologies, gender, health and morbidity; gender differences in the medical encounter; and finally the relevance of a feminist approach to pharmacy practice research, including research questions that are relevant today.     

Correlation between basic fibroblast growth factor immunostaining of stromal cells and stromelysin-3 mRNA expression in human breast carcinoma.

We examined the localization of basic fibroblast growth factor (bFGF) in a series of human breast carcinomas using immunohistochemistry. Staining was observed in tumour cells in 15 out of 54 (28%) tumours and in the adjacent stroma in 34 out of 54 (63%) tumours examined. No correlation was observed between positive staining of these two compartments. The relationship between bFGF staining and expression of the metalloprotease stromelysin-3, and between bFGF and microvessel density, was examined. A statistically significant correlation (P < 0.003) was observed between bFGF staining of the stromal compartment and high expression of stromelysin-3 (ST-3; MMP-11) metalloprotease mRNA by stromal cells. In contrast, no correlation was observed between bFGF and intratumour microvessel density (IMD). These results raise the possibility that bFGF may be involved in the induction of stromelysin-3 mRNA expression in breast cancer stroma.     

Effects of conjugated linoleic acid supplementation on blood lipids and adiposity of rats fed diets rich in saturated versus unsaturated fat

Conjugated linoleic acid (CLA) may decrease adiposity and improve blood lipid profiles under some conditions. The goal of this study was to determine the effects of CLA supplementation on blood lipid profiles and adiposity of rats fed a diet containing a primarily saturated fat versus a diet containing a primarily unsaturated fat. Twenty-eight male Sprague-Dawley rats were randomly assigned to one of four diets containing coconut oil, coconut oil with CLA, corn oil or corn oil with CLA. After 28 days, blood was collected and serum concentrations of total cholesterol (TC), HDL-cholesterol (HDL-C), and triacylglycerols (TG) were assessed. Food intake, body weights, and epididymal fat pads were measured. No significant differences (p>0.05) were noted among groups for amount of food consumed, weight gained, food efficiency ratio or serum TG concentrations. TC concentrations were lower (p<0.05) in the CLA-supplemented rats that were fed coconut oil but not those consuming corn oil. Serum HDL-C was lower (p<0.05) in rats consuming corn oil but was not significantly different (p>0.05) for CLA supplemented groups. Epididymal fat pads weighed significantly more (p<0.05) in the coconut oil fed group compared to the corn oil fed group, but there was no significant difference (p>0.05) between the corn oil and coconut oil + CLA group. Overall, this study suggests that CLA is more beneficial for control of blood lipids and adiposity when supplemented to a diet rich in saturated versus unsaturated fat.     

Mechanical coupling of supracellular stress amplification and tissue fluidization during exit from quiescence

Cellular quiescence is a state of reversible cell cycle arrest that is associated with tissue dormancy. Timely regulated entry into and exit from quiescence is important for processes such as tissue homeostasis, tissue repair, stem cell maintenance, developmental processes, and immunity. However, little is known about processes that control the mechanical adaption to cell behavior changes during the transition from quiescence to proliferation. Here, we show that quiescent human keratinocyte monolayers sustain an actinomyosin-based system that facilitates global cell sheet displacements upon serum-stimulated exit from quiescence. Mechanistically, exposure of quiescent cells to serum-borne mitogens leads to rapid amplification of preexisting contractile sites, leading to a burst in monolayer tension that subsequently drives large-scale displacements of otherwise motility-restricted monolayers. The stress level after quiescence exit correlates with the level of quiescence depth at the time of activation, and a critical stress magnitude must be reached to overcome the cell sheet displacement barrier. The study shows that static quiescent cell monolayers are mechanically poised for motility, and it identifies global stress amplification as a mechanism for overcoming motility restrictions in confined confluent cell monolayers.

Quiescence refers to a state of cell cycle arrest in which cells are retained in a standby mode, ready to re-enter the cell cycle upon activation by a given physiological stimuli. The pool of quiescent cells in the human body is typically represented by tissue-specific stem and progenitor cells, naive immune cells, fibroblasts, and epithelial cells (1, 2). In addition, certain cancer cells have the ability to evade cancer therapy by entering a dormant quiescence-like state (1, 2). Accordingly, careful regulation of entry into and exit out of quiescence is important for several physiological processes such as tissue homeostasis and repair, stem cell maintenance, immunity, reproduction, and development (1, 2).During homeostasis, the balance between quiescent and proliferating cells is controlled by constituents of the microenvironment such as soluble factors, extracellular matrix components, blood vessels, and neighboring cells. On the other hand, during episodes that require extensive tissue renewal and remodeling, for example after injury, coordinated stimulation of quiescent cells into proliferation is facilitated by increased exposure to blood-borne and cell-secreted mitogens through local inflammatory responses such as increased blood flow, increased vascular permeability (vasodilation), and immune cell recruitment (3, 4). Accordingly, a commonly used methodology for studies of quiescence in cultured mammalian cells involves consecutive treatments with serum-free and serum-containing growth medium (1).Quiescent cells are required to maintain a high level of preparedness in order to facilitate rapid activation of specialized cell functions once cell division is stimulated. In agreement with this, quiescent stem cells and naive immune cells have been shown to possess multiple epigenetic and posttranslation mechanisms that facilitate the rapid expression of linage-specific genes following stimulation of quiescence exit (2, 5–14). However, little is known about mechanical forces that facilitate adaptation to cell cycle–activated behaviors.Quiescence exit is frequently associated with activation of cell motility. For example, quiescent stem and naive immune cells migrate out of their niches in response to cell cycle activation in order to support tissue homeostasis, repopulate injured tissue, or to perform immune surveillance at distal locations (15–18). In addition, reawakening of dormant quiescent cancer cells can cause tumor relapse and formation of metastases years after remission (19). In multilayered epithelial tissue, like the skin, exit from quiescence during homeostasis is associated with lateral migration to suprabasal regions, while skin injury evokes massive reawakening of basally localized keratinocytes concomitant with activation of cell sheet displacement by collective migration to restore damaged epidermal surfaces (20–23). The strong correlation between quiescence exit and cell migration in multiple physiological settings suggests the existence of mechanisms that link quiescence exit to activation of cell motility.The dynamics of epithelial collectives is largely regulated by mechanical forces generated through cell–cell interactions as well as interactions between cells and the extracellular environment (24). Key components involved in controlling these forces are cytoskeletal components such as actinomyosin and adhesion complexes such as adherent junctions and focal adhesion complexes (25). Additional factors that have been reported to influence the dynamic behavior of epithelial monolayers include the presence of epithelial edges (24, 26), mechanical stretching or compression (27, 28), expression of the endosomal Rab5 protein (29), exposure of cells to growth factors (30–32), local changes in cell shape (33), and the ability of cells to undergo neighbor exchange (34, 35). In addition, recent studies have also identified a functional link between cell cycle progression and force fluctuation leading to dynamic behavior of cultured epithelial monolayers (36, 37).In this study, we have investigated a mechanical link between quiescence exit and activation of large-scale cell sheet displacements. Using traction force microscopy (TFM), we found that confluent cell monolayers install an actinomyosin-based system during quiescence that produces a coordinated burst of contractile forces and intercellular tension across the epithelial monolayer immediately following exposure to serum-borne mitogens. By combining experiments and theoretical modeling, we show that the amplified forces are essential for driving coordinated cell sheet displacements within otherwise motility-restricted cell monolayers. Furthermore, the magnitude of mechanical forces created during quiescence exit and the extent of cell sheet displacement correlate with quiescence depth. Our study provides evidence that quiescent keratinocyte monolayers possess mechanical preparedness for motility and establish monolayer stress amplification as a strategy for overcoming the motility barrier in confined cell sheets.