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Xixona turrón [Xixona nougat] is a typical Spanish confectionery product made still according to the traditional craft method. This work analyzed the microstructural changes during Xixona turrón manufacture by light microscopy. Different sample preparation methods provided useful complementary information for the understanding of the Xixona turrón structure. A progressively closer contact between a ‘‘sugar phase’’ and a ‘‘fat phase’’ is observed during processing. Inside these phases were immersed many protein bodies and a lot of cellular debris from almond tissue. At the initial stages of mixing the toasted almond paste with the sugar and honey mass, the lipid and sugar phases were relatively discrete. However, as the process developed, the relatively large aerated sugar particles, and to some extent the almond cell debris and protein bodies, were trapped within the lipid phase. In the step when the paste is heated at 65°C, gently stirred, the sugar and plant cell wall material tended to become more finely dispersed. The finished product seemed to consist of twin continuous phases in which the sugar, plant cell wall and protein bodies have formed a ‘‘sugar phase’’ that is infiltrated by the lipid fraction or ‘‘fat phase’’. This structure could contribute to the relatively ‘‘crispy’’ texture of Xixona turrón although the ‘‘oily’’ feel of the product clearly stated that the lipid phase was not extensively encapsulated in the product.

Of 73 essential oils tested for antibacterial activity against Streptococcus pneumoniae R36A (an unencapsulated strain) with a paper disk diffusion assay, three oils were highly inhibitory, fifteen moderately inhibitory and the remainder weakly or non-inhibitory. Three oils from each group were selected and tested with a broth assay in which each oil was added to growing cultures of S. pneumoniae R36A and optical densities (OD) were measured over time. The oils with high antibacterial activity; oregano, thyme and rosewood, induced rapid lysis of R36A as indicated by a decrease in OD, and appearance of dechaining and considerable cell debris within 30 min of addition. The lytic response of R36A to the three oils with moderate activity was variable but all induced some lysis. Oils that were weak inhibitors generally caused slowing of growth but little or no lysis. Several oils were also tested against an encapsulated isolate, S. pneumoniae IC2. Both disk assay and broth results were similar to thos...

The distribution pattern of cellulases in the extracellular and cell associated fractions of Chaetomium erraticum varied depending upon the cultural conditions. The extracellular fractions revealed two forms each of endoglucanase, EG I, EG II and β-glucosidase, β-Glu I, β-Glu II under static and shake conditions. However, the appearance of an additional form of endoglucanase, EG III and β-glucosidase, β-Glu III in static intracellular and cell debris fractions showed a relation of cellulase production with the perithecia development in this fungus. The maximal production of enzymes was observed at 37°C, pH range 5.0–10.0 in the presence of 1–2% carboxy methyl cellulose (CMC) in static cultures (for exoglucanase and β-glucosidase) and shake cultures (for endoglucanase).

To know whether or not molluscs are capable of recognizing tissue alloantigens, dorsal skin-allografts were exchanged between adult terrestrial slug, Incilaria fruhstorferi. We succeeded for the first time in orthotopic transplantation of allografts and observed chronic rejection of allografts. During the first two weeks after transplantation (WAT), in all grafts, both foreign (allo-) and self (auto-), many macrophages infiltrated from the host toward the grafts. This phenomenon is seemed to heal wounds. In the case of autografts, many macrophages observed in the grafted site until 8 weeks, whereas at 4 WAT, grafted tissues such as muscle fibers and mucous cells begun to regenerate slowly and the regeneration of these cells had been over at 20 WAT. However, in the case of allografts, regenerative phenomena were not observed, rather than muscle fibers had been actively attacked by macrophages. Numerous macrophages which phagocytosed cell debris were observed in host connective tissues during this ...

Biotech companies need to reduce time to market and to raise the efficiency of processing in order to lower costs. This paper presents results of the application of computer-based simulations for the rapid formulation of integrated bioprocesses designs and demonstrates the use of simulations to explore the nature and impact of the interactions that exist in a typical bioprocess. An approach for the optimisation of such integrated bioprocesses is presented. Data from a continuous fermentation, with models for cell harvesting, cell disruption and cell debris removal, verified by comparison with pilot-scale data, have been integrated and used to demonstrate the consequences of different process designs and operating decisions on the resulting process performance.

The activation of the complement system leading to generation of anaphylatoxins and the membrane attack complex depends on the chemical nature of the adsorptive system and the anticoagulation used. The method of the primary separation determines the presence of cell debris in the plasma as well as the extent of platelet activation. The particular role of anticoagulation and its properties to prevent/reduce complement activation on immunadsorption material is discussed and the combined use of citrate and heparin is proposed. The quality of the reinfused plasma— as discussed on the example of LDL-apheresis—is therefore influenced by the amount of the activated split products. This determines finally the extent of cellular activation during therapeutic immunadsorption when receptor-dependent activation of cells by C3a(desarg) and C5a(desarg) can occur.

Experiments were carried out aimed at establishing the effects of equipment scale down on the disruption of Baker's yeast cells in high pressure homogenisers. Data are reported on the cell debris particle size distribution (PSD) and on total protein release as a function of the applied pressure for two valve geometries and three scales of operation covering flow rates of 28, 60 and 280 L/h. A comparison of the results from the experiments indicates that over the range of parameters investigated both the total protein release and the cell debris PSDs are independent of valve geometry and flow rate through the homogeniser. These observations are discussed in the light of relevant previous publications. The cell debris PSDs have been simulated by using a recently published model and the total protein release data are described by the well-established Hetherington expression (Hetherington et al., 1971). (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 642-649, 1997.

A new method of poly-β-hydroxybutyrate (PHB) extraction from recombinant E. coli is proposed, using homogenization and centrifugation coupled with sodium hypochlorite treatment. The size of PHB granules and cell debris in homogenates was characterised as a function of the number of homogenization passes. Simulation was used to develop the PHB and cell debris fractionation system, enabling numerical examination of the effects of repeated homogenization and centrifuge-feedrate variation. The simulation provided a good prediction of experimental performance. Sodium hypochlorite treatment was necessary to optimise PHB fractionation. A PHB recovery of 80% at a purity of 96.5% was obtained with the final optimised process. Protein and DNA contained in the resultant product were negligible. The developed process holds promise for significantly reducing the recovery cost associated with PHB manufacture.

Despite the significant advances in cardiac surgery, heart valve replacement still faces a dilemma. While mechanical valves offer lifelong durability they also commit patients to anticoagulation treatment for the rest of their life. On the other hand, bioprosthetic valves have superior hemodynamic performance but durability of the bioprosthesis limits their use to the elderly, with early onset calcification being the primary cause of biomaterial breakdown. Considering that bioprosthetic valves are not reliant upon anticoagulation, there has been much focus on measures to overcome their issues with durability. Firstly, the calcification process has been studied and factors such as young patient age, use of glutaraldehyde fixative, the presence of phospholipids along with cell debris in the valve tissue and mechanical stress have been identified to influence tissue mineralization. Therefore different calcification reduction strategies are being sought: new fixatives have been developed and tested and post-treatments have been added to tissue processing. This review presents the pathophysiology of tissue valve calcification and focuses on the multiple approaches developed to prevent bioprosthetic heart valve calcification, as well as on their general outcomes and translation to clinical applications.

We fabricated a microfluidic device consisting of ciliated micropillars, forming a porous silicon nanowire-on-micropillar structure. We demonstrated that the prototype device can preferentially trap exosome-like lipid vesicles, while simultaneously filtering out proteins and cell debris. Trapped lipid vesicles can be recovered intact by dissolving the porous nanowires in PBS buffer.

Exposure to contaminated aerosols and water originating from water features may pose public health risks. Endotoxins in air and water and fecal bacteria in water of water features were measured as markers for exposure to microbial cell debris and enteric pathogens, respectively. Information was collected about wind direction, wind force, distance to the water feature, the height of the water feature and the tangibility of water spray. The mean concentration of endotoxins in air nearby and in water of 31 water features was 10 endotoxin units (EU)/m(3) (Geometric Mean (GM), range 0-85.5 EU/m(3) air) and 773 EU/mL (GM, range 9-18,170 EU/mL water), respectively. Such mean concentrations may be associated with respiratory health effects. The water quality of 26 of 88 water features was poor when compared to requirements for recreational water in the Bathing Water Directive 2006/7/EC. Concentrations greater than 1000 colony forming units (cfu) Escherichia coli per 100 mL and greater than 400 cfu intestinal enterococci per 100 mL increase the probability of acquiring gastrointestinal health complaints. Regression analyses showed that the endotoxin concentration in air was significantly influenced by the concentration of endotoxin in water, the distance to the water feature and the tangibility of water spray. Exposure to air and water near water features was shown to lead to exposure to endotoxins and fecal bacteria. The potential health risks resulting from such exposure to water features may be estimated by a quantitative microbial risk assessment (QMRA), however, such QMRA would require quantitative data on pathogen concentrations, exposure volumes and dose-response relationships. The present study provides estimates for aerosolisation ratios that can be used as input for QMRA to quantify exposure and to determine infection risks from exposure to water features.

Current ureteral stents, while effective at maintaining a ureteral lumen, provide a substrate for bacterial growth. This propensity for biofilm formation may be a nidus for bacterial growth leading to infection and a reason for early removal of a stent before it is clinically indicated. A newly devised stent, composed of a highly hydrated, partially hydrolyzed polyacrylonitrile polymer, is believed to have bacterial resistant properties. The objective of this study is to evaluate the biofilm growth and bacterial resistant properties of this novel stent. Multiple 1 cm sections of the pAguaMedicina™ Pediatric Ureteral Stent (pAMS) (Q Urological, Natick, MA) and the conventional polymer stent (SS) (Boston Scientific, Natick, MA) were incubated for 3 days in the 3 different growth media. Afterward, J96 human pathogenic Escherichia coli was added. At 3, 6, 9, 12, and 15 days following bacterial inoculation, the stent segments were washed, sonicated, and analyzed for bacterial growth. Scanning electron microscopy (SEM) imaging was performed to assess biofilm formation. pAMS demonstrated significant reductions (43–71 %) in bacterial counts when compared to standard stents in all conditions tested. SEM imaging demonstrated biofilm formation on both types of stents in all media, with a relative reduction in apparent cell debris and bacteria on the pAMS. In this study, the gel-based stent shows a demonstrable reduction in bacterial counts and biofilm formation. The use of the pAMS may reduce the risk of infection associated with stent usage.

Genetic methods are becoming increasingly relevant for addressing food authentication problems and include a wide range of techniques and equipment. DNA is present in all biological tissues and can potentially be recovered from any matrix containing even a very small number of cells or cell debris. Important characteristics that make DNA particularly suitable for the analysis of food products are its high information content and resistance to degradation. The current knowledge of partial or complete DNA sequences in a large number of species already allows for optimization of DNA-based methods with high sensitivity and specificity for the genetic target under analysis. The challenges presented by food products with PDO (protected designation of origin) are diverse and may include the identification of individuals, species, breeds, cultivar, or variety in animals, plants, fungi, and microorganisms. Most of the currently used genetic methods rely on polymerase chain reactions for the survey of informative DNA present in food matrices. Methods that can be applied in automated and high-throughput settings for large-scale screening purposes are particularly important. This review is intended to provide an overview of the DNA-based strategies and analytical methods available for the analysis of food products in the context of PDO authentication.

Protein recovery from a bacterial lysate was accomplished using crossflow microfiltration with rapid backpulsing. The net flux with backpulsing was found to increase with increasing forward and backpulse pressures, increase to a maximum and then decrease with increasing forward filtration time between backpulses (or decreasing backpulse frequency), increase weakly with increasing shear rate, and decrease strongly with increasing concentration in the feed. Variation of the operating conditions for a dilute feed of 0.0025 g cell debris/g suspension on a wet cell mass basis yielded net flux values as high as 4.5×10 −3 cm/s (160 1/m 2 h) with backpulsing, compared to a steady-state value of 4.0×10 −4 cm/s (14 1/m 2 h) for similar conditions without backpulsing. The optimal backpulse frequency was found to be very high, about 2.5 times per second, for the minimum backpulse duration of 0.09 s. However, the performance of the backpulsing operation declined with increasing concentration of cell debris, with no flux improvement achieved for concentrations greater than 0.01 g cell debris/g suspension. Nevertheless, 100% protein transmission with backpulsing was achieved for all conditions investigated, compared to an average value of 60% transmission in the absence of backpulsing. Thus, rapid backpulsing is an effective method for the recovery of protein from dilute cell debris.

A practical study is presented of the influence of cell debris and polymer recycling upon the operation of two-stage aqueous two-phase systems (ATPS) for the recovery of yeast bulk protein, pyruvate kinase and fumarase. Brewers' yeast was disrupted using one of two types of high-pressure homogenisers or a bead mill. The different cell debris suspensions were partitioned in a single PEG-phosphate ATPS extraction and the efficiency of solid-liquid separation was examined. A continuously operated two-stage ATPS process, using spray columns, is presented and practical problems of polymer recycling are discussed. Conclusions are drawn concerning the generic implementation and operational stability of ATPS in practical protein recoveries.

The development of a model for simulating the recoveries by pilot-scale disc-stack centrifugation of whole yeast cells, yeast cell debris and protein precipitates prepared by ammonium sulphate salting-out is presented. The model is based on the grade efficiency concept and incorporates the effects of hindered settling at high biomass concentrations and the breakage of shear-sensitive material within the centrifuge feed-zone to give an accurate prediction of solid/liquid separation. The simulations have been proven by comparison with data from pilot-scale verification trials. The trials have highlighted where improvements to the models were required to increase their accuracy. The value of verification trials in proving the validity of models is commented upon.

Asymmetrical flow FFF has been applied to characterize Saccharomyces cerevisiae cells, the morphology of which has been assessed by image analysis, during fermentation on glucose medium. Full cells, budding or non-budding, are eluted according to the steric-hyperlayer modes, while macromolecules and other cell debris are eluted according to the normal mode.

Joint manifestations in patients with rheumatoid arthritis (RA) are usually caused by the rheumatoid disease or, less often, by secondary osteoarthritis or an infection. Effusions related to crystal deposits have been reported but are uncommon. We report on seven patients with quiescent RA who presented with incompletely explained, acute, mostly monoarticular, joint or bursal exacerbations that may have been caused by apatite or lipid crystals or by reactions to tissue and cell debris. In one of these patients, the joint symptoms were related to the development of pigmented villonodular synovitis. Whether or not our hypothesized mechanisms are correct, it is important to be aware that exacerbations in a single or a few sites out of proportion to the rest of the RA need not be because of activity of the RA or infection. This awareness can prevent inappropriate aggressive treatment of the rheumatoid disease or extensive antibiotic therapy. In our cases, careful analysis of the synovial fluid was helpful in ascertaining that active RA was less likely and in identifying some possible causes of the effusions.

An original procedure which permits to isolate circulating immune complexes (CIC) from the blood plasma in a form of a dense pellet was developed. This procedure was applied for the ultrastructural analysis of CIC isolated from blood of healthy blood donors and patients suffering from Yersinia enterocolitica (YE) and Yersinia pseudotuberculosis (YP) infections. The here reported method of CIC isolation from blood plasma permitted to visualize CIC electronmicroscopically as amorphous masses of low, middle, and high electron density with inclusions of cell debris. In contrast to CIC of healthy blood donors, CIC of infected patients contained various bacteria and fungiformic structures. For the first time, this method made possible an ultrastructural demonstration of bacterial destruction outside of phagocytes in vivo. This method also permits to visualize and identify bacteria in cases of lingering forms of infection when hemoculture tests fail. Therefore, electronmicroscopic examination of CIC preparations from the blood plasma might be a very informative indicator of bacteriemia in the course of an infection process and serve as an indicator of therapeutic effects. In lingering forms of an infection process, ultrastructural analysis of CIC preparations can be of prognostic value and serve as an indicator of therapeutic effects. This method might be also advantageous as an additional test for the exposure of latent bacterial persistence in diagnostically complicated cases.

It has been generally accepted that blood serum and plasma are free of cellular components. Although the precise quality and quantity of DNA needed for reliable identification analysis is unknown [1,2], the cell debris and molecules released by cells during apoptosis are known to provide sufficient amounts of DNA for genetic analysis [1,3-6]. In real-time situations, serum/plasma samples can play a crucial role in personal identification. For instance, if patient samples prepared for testing are mixed up in-hospital for any reason, the consequences can be critical. In such cases, the serum/plasma DNA can be extracted from the patient’s sample and can be used to conduct a search for the identification of its rightful owner.

Mesenchymal stem cells (MSC) are under investigation as a therapy for a variety of disorders. Although animal models show long term regenerative and immunomodulatory effects of MSC, the fate of MSC after infusion remains to be elucidated. In the present study the localization and viability of MSC was examined by isolation and re-culture of intravenously infused MSC. C57BL/6 MSC (500,000) constitutively expressing DsRed-fluorescent protein and radioactively labeled with Cr-51 were infused via the tail vein in wild-type C57BL/6 mice. After 5 min, 1, 24, or 72 h, mice were sacrificed and blood, lungs, liver, spleen, kidneys, and bone marrow removed. One hour after MSC infusion the majority of Cr-51 was found in the lungs, whereas after 24 h Cr-51 was mainly found in the liver. Tissue cultures demonstrated that viable donor MSC were present in the lungs up to 24 h after infusion, after which they disappeared. No viable MSC were found in the other organs examined at any time. The induction of ischemia-reperfusion injury in the liver did not trigger the migration of viable MSC to the liver. These results demonstrate that MSC are short-lived after i.v. infusion and that viable MSC do not pass the lungs. Cell debris may be transported to the liver. Long term immunomodulatory and regenerative effects of infused MSC must therefore be mediated via other cell types.

Microparticles ( MP) are small membrane bound vesicles which have been described in circulation. They are derived from a variety of cells by an active process of shedding. They are bound by plasma membrane, are anucleate but may contain DNA or RNA and may be virtually derived from any cell (Ahn 2005, Mause, et al, Porto, et al). The majority of the microparticles in blood are derived from platelets. Previously considered as cell debris they are now regarded as vectors for transfer of biological information. The MP production is thought to reflect a balance between cell stimulation, proliferation and death. Based on their potential function and pathophysiologic effect, MP are thought to be physiological or patholological. MP play a role in normal haemostasis and abnormal amplification of MP production leading to a pathological state (Meziani, et al). For example, excessive MP from platelets may contribute to thrombosis (Siljander, et al 1996). Their role in vascular biology is being uncovered with increasing evidence for their role in venous thromboembolism. This chapter will explore the role of these MP in the physiology of haemostasis as well as pathology of thromboembolism. The final section will discuss the current state of art in the methods used to detect and measure MP.

Present in all organs, mononuclear phagocytes consist of a heterogeneous population of hematopoietic cells whose main role is to ensure tissue homeostasis through their ability to scavenge cell debris, promote tissue repair and maintain tolerance to self-antigens while simultaneously inducing innate and adaptive immune responses against foreign antigens that breach the tissue. The intestinal mucosa is particularly exposed to foreign antigen, through constant exposure to high loads of commensal bacteria and dietary antigens as well as providing a site of entry for viral and bacterial pathogens. The molecular mechanisms that control the intestinal ability to distinguish between “innocuous” and “dangerous” antigens remains poorly understood although it is clear that mononuclear phagocytes play a key role in this process. This review highlights recent advances in our understanding of heterogeneous origin of the mononuclear phagocytes that inhabit the intestinal mucosa and discusses how developmental diversity allows for functional diversity to ensure intestinal integrity.

Exosomes are small membrane vesicles of endosomal origin, which are secreted from a variety of cell types. During the 1980s exosomes were first described as organelles to remove cell debris and unwanted molecules. The discovery that exosomes contain proteins, messenger and microRNAs suggests a role as mediators in cell-to-cell communication. Exosomes can be transported between different cells and influence physiological pathways in the recipient cells. In the present review, we will summarize the biological function of exosomes and their involvement in physiological and pathological processes. Moreover, the potential clinical application of exosomes as biomarkers and therapeutic tools will be discussed.

In KCS, with the slit lamp, are often visible floating particles moving with blinks; such particles are usually termed tear film debris. This debris contains two components: mucus and cell debris/fragments.

A simple and rapid spectrophotometric method for measuring recombinant inclusion body concentrations in the presence of Escherichia coli cell debris has been applied to monitoring the performance of an industrial disc stack centrifuge. Turbidimetric measurements were made at two wavelengths, i.e., 600 nm and 420 nm, and the ratios of OD(600nm)/OD(420nm) related to the particle composition in suspension. The principle behind the technique is that inclusion body particles scatter light at 600 nm more effectively than do smaller cell debris particles when compared with the degree of light scatter at 420 nm. This technique may have broad potential application in developing an automatic monitoring and control system for industrial-scale inclusion body recovery. (c) 1994 John WileySons, Inc.

In order to automate measurements of cell concentration and viability in a suspended animal cell culture, we have developed an in situ microscopic image analysis system with an effective cell recognition algorithm. With a small amount of sample, this system can measure the cell density rapidly and aseptically. In addition, it can measure a cell size histogram including cell debris small particle distribution. These small particles have been found to be related to the viability of the mouse-mouse hybridoma STK1 cell line. By using cell debris small particle density as an indicator of cell viability, the developed system provides non-destructive viability monitoring without trypan blue staining.

The smallest discernible entity is a rounded, light-reflecting subsurface cell (about 10–15 μm in diameter). Such cells are present individually, in small groups, or aggregated in larger lesions (of about 150–400 μm in diameter, coarse lesions with the slit lamp). The nature of these cells, so clearly abnormal to the corneal epithelium, is not clear; they may represent damaged epithelial cells, invading inflammatory cells, or both. In some of the larger lesions small groups of aggregated rounded/abnormal cells are discernible, in others they just seem heaped-up and/or mixed with cell debris. The lesions’ shapes vary between rounded and somewhat irregular. All show rounded/abnormal cells at the edges, which thus appear rugged. The rounded/abnormal cells, whether individual or aggregated, are superficially located, but their exact location in depth cannot be estimated in two-dimensional images. The absence of changes indicating stromal involvement suggests an intraepithelial location. Subepithelial opacities, if developing, appeared in the present patients as a mild, transient subepithelial haze lacking abnormal cells; no informative photographs could be obtained from them.

Aqueous two-phase system (ATPS) is a liquid–liquid separation technique that has shown great potential for the extraction, recovery, and purification of a great variety of biological compounds. The main advantages of this technique over other separation methodologies for proteins and other compounds include scaling-up feasibility, process integration capability, biocompatibility, and, most importantly, continuous operation. In this article, a general overview regarding the basis and applications of ATPS is presented. The general theory concerning the formation of ATPS and the parameters with significant effect on the partition behavior of biological products are presented. Different strategies for the integration of bioprocesses using ATPS as well as the bioaffinity partition of proteins and other molecules are discussed. Subsequently, the practical application of ATPS-based strategies for the downstream processing of biological products including proteins and nucleic acids, bionanoparticles (virus, virus-like particles, and nanostructures), biomass (cells, cell debris, and organelles), and low-molecular-weight compounds (metabolites and phytochemicals) is presented, and other ATPS-based applications and future trends are briefly discussed.

We describe a new mass isolation procedure for both pure and stage-specific phagosomes from Tetrahymena thermophila. We prepared magnetic iron dextran particles about 1 μm in diameter to label the phagosomes. The oral apparatus of the cells concentrated these particles so readily that after 1 min the majority of the cells had formed a single phagosome. A short wash removed non-ingested particles, enabling us to follow the age-dependent changes of a single labeled phagosome through the cell. Phagosomes of different ages, including very young and nascent phagosomes, were removed easily from the non-magnetic cell debris of mechanically homogenized cells by means of a permanent magnet. The isolated phagosomes are pure as tested by enzymatic assays and light and electron microscopy. Since the yield of pure phagosomes of all ages is high (∼ 90%), this method could be generally applied for phagosome isolation from ciliates.

A rapid procedure for effective purification of large quantities of coccolith ultrafine particles from marine algae is reported. Coccoliths are detached from cells by optimized sonication in the presence of 50 mM NaHCO3. Contaminating cell debris is then removed from coccoliths by cycles of washing and floatation. Coccolith particles were purified fromEmiliania huxleyi andPleurochrysis carterae. The surface area of these particles is three to five times greater than synthetic calcite particles. Glucose oxidase and uricase have been immobilized onto purified coccolith ultrafine particles to illustrate their potential as a support material for biotechnological application.

In the regeneration of peripheral nerves, Schwann cells guide the direction of regenerated axons.This study was designed to observe axonal regeneration under the following conditions:(1) The presence of viable Schwann cells;(2) The presence of viable Schwann cell basal lamina alone; and(3) The absence of all viable tissue components.The experimental groups were prepared as follows and the process of axonal regeneration was examined by transmission electron microscopy.(1) The sciatic nerves of rat were transected and sutured. The nerve segments were observed in the distal stump.(2) The sciatic nerves of rats were excised and grafted to lyophilized homologus nerves.(3) Similarly, the sciatic nerves were excised. Polyglycolic acid (P. G. A.) fibers were inserted in silicone tubes and grafted to the nerve gaps.The results were as follows:1. In the distal stump which underwent transection and suture of nerve fibers, Schwann cells phagocytized degenerating myelin sheaths and cell debris and guided regenerating axons.2. In the lyophilized homologous nerve grafts, degenerated myelin sheaths and cell debris were phagocytized by macrophages, but the Schwann cell basal lamina remained.3. In the lyophilized homologous nerve grafts, regenerating axons grew in contact with the inner surface of the basal lamina scaffolds of the Schwann cells.4. In the tubulization group, regenerated axons were near the P. G. A. fibers and accompanied by Schwann cells.These findings indicate that the basal lamina scaffolds of Schwann cells function as pathways for guiding the direction of regenerating axons and Schwann cells.

It is important to prevent unexpected laboratory infections in a biosafety area. It is recommended that extreme caution should be used when handling needles and syringes to avoid autoinoculation, and that needles and syringes should be used only when there is no alternative. To remove cells and cell debris, a disk-type microfilter unit, which is recommended using a needle, has been used for filtrating supernatant from HIV-1-infected cell cultures. We compared a stick-type microfilter unit, which can be used without a needle, with a disk-type one for their safety and recovery of human immunodeficiency virus particle after filtration. To confirm the right of our comparison, we observed the filter electron microscopically for the virus particles and virus suspensions were carried out and discussed. In conclusion, the stick-type filter should be improved, since the filter unit is inferior to the disk-type filter unit in purification of the virus, but for the safety is superior to the disk-type.

International audience; Matrix-assisted laser desorption/ionization (MALDI) molecular imaging technology attracts increasing attention in the field of biomarker discovery. The unambiguous correlation between histopathology and MALDI images is a key feature for success. MALDI imaging mass spectrometry (MS) at high definition thus calls for technological developments that were established by a number of small steps. These included tissue and matrix preparation steps, dedicated lasers for MALDI imaging, an increase of the robustness against cell debris and matrix sublimation, software for precision matching of molecular and microscopic images, and the analysis of MALDI imaging data using multivariate statistical methods. The goal of these developments is to approach single cell resolution with imaging MS. Currently, a performance level of 20-μm image resolution was achieved with an unmodified and commercially available instrument for proteins detected in the 2-16-kDa range. The rat testis was used as a relevant model for validating and optimizing our technological developments. Indeed, testicular anatomy is among the most complex found in mammalian bodies. In the present study, we were able to visualize, at 20-μm image resolution level, different stages of germ cell development in testicular seminiferous tubules; to provide a molecular correlate for its well established stage-specific classification; and to identify proteins of interest using a top-down approach and superimpose molecular and immunohistochemistry images.

Emily Dey-Hazra1* Barbara Hertel1* Torsten Kirsch1 Alexander Woywodt2 Svjetlana Lovric1 Hermann Haller1 Marion Haubitz1 Uta Erdbruegger1,31Division of Nephrology, Department of Medicine, Hannover Medical School, Hannover, Germany; 2Renal Unit, Lancashire Teaching Hospitals NHS Foundation Trust, Preston, Lancashire, UK; 3Division of Nephrology, University of Virginia at Charlottesville, VA, USA; *These authors contributed equally to this work.Abstract: The clinical importance of microparticles resulting from vesiculation of platelets and other blood cells is increasingly recognized, although no standardized method exists for their measurement. Only a few studies have examined the analytical and preanalytical steps and variables affecting microparticle detection. We focused our analysis on microparticle detection by flow cytometry. The goal of our study was to analyze the effects of different centrifugation protocols looking at different durations of high and low centrifugation speeds. We also analyzed the effect of filtration of buffer and long-term freezing on microparticle quantification, as well as the role of Annexin V in the detection of microparticles. Absolute and platelet-derived microparticles were 10- to 15-fold higher using initial lower centrifugation speeds at 1500 × g compared with protocols using centrifugation speeds at 5000 × g (P < 0.01). A clear separation between true events and background noise was only achieved using higher centrifugation speeds. Filtration of buffer with a 0.2 µm filter reduced a significant amount of background noise. Storing samples for microparticle detection at -80°C decreased microparticle levels at days 28, 42, and 56 (P < 0.05 for all comparisons with fresh samples). We believe that staining with Annexin V is necessary to distinguish true events from cell debris or precipitates. Buffers should be filtered and fresh samples should be analyzed, or storage periods will have to be standardized. Higher centrifugation speeds should be used to minimize contamination by smaller size platelets.Keywords: circulating microparticles, detection method, flow cytometry

The effect of dimercaptosuccinic acid (DMSA) on the tissue distribution, renal and hepatic subcellular localization of Cd2+, Zn2+ and Cu2+ in Cd(2+)-pretreated male rats and on the tissue distribution of Zn2+ and Cu2+ in the normal rat was studied. Cd(2+)-pretreated rats which received 3 x 1 mg Cd2+/kg body wt s.c. at 48 hr intervals followed after 7 days by DMSA (50 mg/kg body wt i.p.) daily for 17 days had total hepatic Cd2+ concentrations 25 per cent lower than Cd(2+)-pretreated controls (P0.01). DMSA did not influence the concentration or distribution of Cd2+ in the liver cytosol whereas in the mitochondrial-lysosomal and nuclei + cell debris fractions the Cd2+ concentration was reduced by 54 and 48 per cent respectively. Total renal and hepatic Cu2+ concentrations were increased by Cd2+ treatment and reduced by treatment of the Cd(2+)-exposed animal with DMSA. In the liver cytosol Cu2+, Zn2+ and Cd2+ accumulated in the metallothionein fraction and none was mobilized from the cytosol by DMSA. In the kidney cytosol Cu2+ accumulated in fractions in addition to metallothionein and was eliminated from each of these fractions following treatment with DMSA. It is concluded that the high affinity of metallothionein for these cations prevented their elimination from the cytosol and that the interaction of Cd2+ and Cu2+ with DMSA occurred in the particulate fraction and therefore delayed the response to DMSA treatment. It is suggested that long term treatment with DMSA, although ineffective in mobilizing Cd2+ from the kidney may provide a useful therapeutic measure to reduce the liver burden of Cd2+ and the high renal Cu2+ concentrations in the Cd(2+)-exposed animal.

The goal of this comparative study was to investigate biofilm forming microorganisms living in washing machines (WMs). Biofilms were sampled from 11 washing machines from four countries and three continents. Among the 94 isolated strains, 30% were potential human pathogens. Representative strains were selected and biofilm formation was evaluated with the crystal violet (CV) assay. The majority of the WM isolates formed more biofilm than their reference strains. Biofilms of P. putida WM (the largest biofilm producer) were exposed to different concentrations (0.0007-7 g l(-1)) of the standard detergent IEC-A* at 30°C for 30 min and observed with confocal laser scanning microscopy. Using quantitative CVA, P. putida WM biofilm removal required higher detergent concentrations than the type strain. However, for both strains the recommended detergent concentration (7 g l(-1)) was insufficient to completely clean surfaces from cell debris and exopolymeric substances.

Introduction Centrifugal Separation Types of Centrifugal Separators General Disk Bowl Machines Decanter Centrifuges Other Classical Bowl Designs New Bowl Designs Summary Fluid and Particle Dynamics Introduction Centrifuges with Conical Disks Decanter Centrifuges The Theoretical Size of a Centrifugal Separator Introduction The Σ Theory Separation Efficiency The KQ Formula for Disk Bowl Centrifuges Hindered Settling Selection of Type and Size of Centrifuge Introduction Main Process Parameters Test Tube Centrifugation (Spin Test) Important Properties of the Process Streams Improvement of Separability Pilot Machine Testing Scale-Up Description of Some Applications Introduction Cell Harvesting Cell Debris Inclusion Body Recovery and Washing Extraction of Cell-Free Broth Precipitation Whole-Broth Extraction Installation and Operation Plant Design Cleaning-in-Place Containment, Asepsis, and Explosion Protection Sterilization Centrifugation versus Microfiltration Nomenclature Bibliography Keywords: asepsis; cell debris separation; cell harvesting; centrifugation; containment; scale-up; separability; solvent extraction; spin test; sterilization; two-phase aqueous systems

Background Lipomaisthemostcommonbenignmesenchymaltumorcomposedofmature fatcells.Thestandardtreatmentforlipomaisexcision.Manytreatmentshavebeendescribed inordertominimizethescarsproducedbysurgicalexcision.Thetreatmentoflipomausinga subdermallaserproducesaneffectivedisruptionoffatcellsandresultsinasmallscar. Objective To evaluate the efficacy of subcutaneous intralesional application of a pulsed Nd:YAG laser as an option for the treatment of lipoma. Methods From January 2001 to November 2007, 20 patients (11 women and nine men) with lipomas were treated using a subdermal, pulsed, 1064-nm Nd:YAG laser. After laser treatment, the oily solution, the product of laser action, was removed with a 2-mm cannula using a negative pressure of 350 mmHg. Histology and cytology of the treated tissue were used to analyze the effects of the laser on the fat cells. Ultrasound was performed in some subjects before and after laser treatment. Results Subdermal lipoma treatment using a 1064-nm Nd:YAG laser resulted in complete or almost complete removal of the tumor in 100% of patients. Four partial relapses were observed that were treated successfully by the same procedure. Adverse effects were mild and temporary. The combination of a 1064-nm Nd:YAG laser and removal of the cell debris by a suction cannula presented an effective therapeutic option for patients with lipoma. Conclusions The treatment of lipoma using a 1064-nm Nd:YAG laser is a minor invasive procedure which does not result in large scars. Laser treatment is an effective and safe option for cellular disruption.

Flow cytometric assessments of DNA ploidy status and the S-phase fraction (SPF) have been shown to yield prognostic information in breast cancer. The aim of the present investigation was to elucidate the reproducibility of results with regard to tumor DNA heterogeneity, and to ascertain whether the prognostic value of DNA measurements might be enhanced by analyzing two pieces of a tumor instead of one. Agreement with regard to ploidy status (diploid versus non-diploid) was obtained in 90% of cases (71/79) when two adjacent sections of the tumor were investigated, and in 77% of cases (10/13) when four biopsies from different quadrants of the tumor specimen were investigated. The corresponding figures for agreement in SPF (divided into three categories, less than 7.0%, 7.0-11.9%, and greater than or equal to 12%) were 75% (59/79; 2-sample series) and 55% (7/13; 4-biopsy series). The main reason for variance in ploidy results was the difficulties in distinguishing near diploid cell populations. Discrepancies in SPF categories could be explained by minor fluctuations in SPF values near the cut-off levels, or by variance in ploidy status, the fraction of non-diploid nuclei, and background noise due to cell debris. There was a stepwise increase in recurrence rate (RR) among patients with increasing SPF category (RR: 20%, 41%, and 53%). Patients whose SPF categories varied, from low or intermediate in one part of the tumor to high in another, seemed to have a poor prognosis (RR = 57%).(ABSTRACT TRUNCATED AT 250 WORDS)

A decellularization method using high-hydrostatic pressure (HHP) technology (>600MPa) is described. The HHP disrupts the cells inside the tissue. The cell debris can be eliminated with a simple washing process, producing clean, decellularized tissue. In this study, porcine aortic blood vessel was decellularized by HHP. The mechanical properties and in vivo performance of the decellularized tissue were evaluated. Mechanical properties of the decellularized tissue were not altered by the HHP treatment. Reduced inflammation of the decellularized tissue was confirmed by xenogenic transplant experimentation. An allogenic transplantation study showed that decellularized blood vessel endured the arterial blood pressure, and there was no clot formation on the luminal surface. In addition, cellular infiltration into the vessel wall was observed 4 weeks after implantation, suggesting that HHP treatments could be applied widely as a high-quality decellularization method.

PURPOSE: To determine the main causes of intrastromal corneal ring segment (ICRS) explantation and the relationship with the microscopic findings on the ICRS surface. SETTING: Vissum Corporation-Instituto Oftalmologico de Alicante, Alicante, Spain. METHODS: This study evaluated ICRS that were explanted in centers in Spain from 2000 to 2008. Clinical data (reasons for explantation, date of implantation/explantation, tunnel creation technique, ICRS type) and scanning electron microscopy findings on the ICRS surface (adherent tissue-like material, cell deposits, protein) were documented. RESULTS: Intrastromal corneal ring segments were explanted from 58 eyes (47 patients). The main cause was extrusion (48.2% of explanted segments), followed by refractive failure (ie, poor refrac- tive outcome) (37.9%), keratitis (6.8%; 3.7% culture positive), and corneal melting and perforation (6.8%). Scanning electron microscopy showed cells and cell debris on the ICRS explanted by extrusion, a clean surface on the ICRS explanted for refractive failure, and bacteria (cocci) in the case of proven infectious keratitis. CONCLUSIONS: The main cause of explantation was extrusion of the ICRS followed by refractive failure. There was a clear correlation between the cause of explantation and the microscopic findings on the ICRS. Extrusion was accompanied by inflammatory cells and cell debris on the ICRS surface. No inflammatory reaction was observed on the ICRS explanted for refractive failure. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Summary Attention has already been drawn to the presence of pulmonary intravascular macrophages (PIMs) in species in which the lung plays an important part in the removal of particles from the bloodstream. The stimulation of PIMs under certain conditions has been related to pulmonary oedema and congestion. In order to ascertain whether these cells are found in rabbits, healthy animals were inoculated with a liver homogenate obtained from animals which had- died of rabbit haemorrhagic disease, a condition characterized by vascular phenomena and pulmonary oedema. PIMs were detected both in experimental and healthy control animals. They shared the morphological characteristics reported for other species, particularly with respect to the presence of intercellular junctions with endothelial cells. In experimental animals, PIMs were actively involved in the removal of cell debris which may or may not have been associated with the presence of rabbit haemorrhagic disease virus antigen.

We report here an improved method for nuclei counting utilizing Triton-X 100 to reduce the size of cell debris, thereby allowing the use of a particle sizer/counter. Furthermore, nuclei are completely released within 30 seconds, as compared to 1 hour using hypotonic solution. The method is accurate above 0.3 × 106 cells/mL.

A precursor of ConBr, a glucose/mannose-binding plant lectin, was expressed in the yeast Pichia pastoris. Western blot analysis of transformed cells detected an intracellularly recombinant protein band with ca. 34.5 kDa. The recombinant protein was apparently active as suggested by its strong interaction with the mannose-rich yeast cell debris.

Expanded-bed adsorption (EBA) chromatography is a convenient and effective technique for the capture of proteins directly from unclarified crude sample. In EBA chromatography, the settled bed is first expanded by upward flow of equilibration buffer. The crude feed, a mixture of soluble proteins, contaminants, cells, and cell debris, is then passed upward through the expanded bed. Target proteins are captured on the adsorbent, while particulates and contaminants pass through. A change to elution buffer while maintaining upward flow results in desorption of the target protein in expanded-bed mode. Alternatively, if the flow is reversed, the adsorbed particles will quickly settle and the proteins can be desorbed by an elution buffer. The mode used for elution (expanded-bed versus settled-bed) depends on the characteristics of the feed. After elution, the adsorbent is cleaned with a predefined cleaning-in-place (CIP) solution, with cleaning followed by either column regeneration (for further use) or storage.