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By the separation of Toxoplasma lysate using two-dimensional gel electrophoresis and its analysis with human serum samples and mass spectrometry, the subtilisin-like protein (SUB1) was identified to be a potential marker for acute toxoplasmosis. Following expression of the C-terminal domain of SUB1 in Escherichia coli, it was tested in a line blot assay using a total of 80 human serum samples. Two computer programs based on different evaluation strategies were used for judgment of the line blot results: (i) a time-dependent method with a predefined cutoff value and (ii) a fixed-time-point method with a calculated cutoff. Thereby, SUB1 was proven to be rather reactive with specific immunoglobulin A (IgA), IgM, and IgG of patients with an acute infection. This finding makes this antigen an attractive candidate for improving diagnosis of toxoplasmosis and demonstrates that not only the selection of respective antigens but also the evaluation method chosen are important for the evaluation of new diagnostic markers.

ABSTRACTBy the separation of Toxoplasmalysate using two-dimensional gel electrophoresis and its analysis with human serum samples and mass spectrometry, the subtilisin-like protein (SUB1) was identified to be a potential marker for acute toxoplasmosis. Following expression of the C-terminal domain of SUB1 in Escherichia coli, it was tested in a line blot assay using a total of 80 human serum samples. Two computer programs based on different evaluation strategies were used for judgment of the line blot results: (i) a time-dependent method with a predefined cutoff value and (ii) a fixed-time-point method with a calculated cutoff. Thereby, SUB1 was proven to be rather reactive with specific immunoglobulin A (IgA), IgM, and IgG of patients with an acute infection. This finding makes this antigen an attractive candidate for improving diagnosis of toxoplasmosis and demonstrates that not only the selection of respective antigens but also the evaluation method chosen are important for the evaluation of new diagnostic markers.

The results of an inter laboratory comparison of thermal conductivity, thermal diffusivity, specific heat capacity, and thermal expansion measurements on austenitic stainless steel in the temperature range between 20 and 1000°C are presented here. Mean values are presented for the physical properties studied. Reliable relative expanded uncertainties can be stated for the properties determined, which were achieved by applying good measurement practice, i.e., 3% for thermal expansion, 5% for specific heat capacity and thermal diffusivity, and 6% for thermal conductivity. The mean values derived from this intercomparison agree well with the results of a previous intercomparison in 1990.

Purpose: The aim of this study was to assess dental anchorage qualities when the pendulum appliance is used for distal molar movement. Material: Thirty adolescents in various dentition stages received a modified pendulum appliance with a distal screw and a specially preactivated pendulum spring for bilateral molar distalization in the maxilla. The subjects were subcategorized into 3 groups of 10 according to the dental anchorage used: deciduous molars, premolars and deciduous molars, or only premolars. Dentoalveolar effects and side effects in the anchorage unit and in the molar area were determined by cephalometric analysis. Results: Statistical analysis of the measurements showed significant differences between groups in the extent of molar distalization and the resulting incisor protrusion. Distal tipping of the 6-year molars was significantly less severe (2.3^o +/- 1.58^o to the palatal plane and 2.55^o +/- 1.52^o to the anterior cranial base) in patients with premolar anchorage than in those with deciduous molar anchorage (6.15^o +/- 3.42^o and 6.35^o +/- 3.46^o). Incisor protrusion was significantly more pronounced in patients with deciduous molar anchorage (2.75 +/- 1.4 mm) than in the other 2 groups (1.65 +/- 0.82 mm, mixed deciduous molar and premolar anchorage, and 1.75 +/- 0.75 mm, premolar anchorage). Additionally, incisor protrusion was translatory compared with controlled tipping in subjects with deciduous molar anchorage or premolar and deciduous molar anchorage. Conclusions: Deciduous molars and premolars can be used for anchorage for molar distalization with a pendulum appliance; however, anchorage with premolars only results in the least pronounced dentoalveolar side effects. The anchorage quality of deciduous molar and mixed deciduous molar/premolar anchorage is limited.

Foams of Al2O3and apatite ceramics with interconnecting pores were produced using a new technique. The surfaces of the ceramics served as substrates for the culture of human peripheral and bone marrow derived stem cells. Up to 27 days the cells were kept in culture where they proliferated and developed into different morphologies consistent with bone marrow cell lines.

A hollow fiberinfiber–based bioreactor system was tested for the applicability to host kidney epithelial cells as a model system for a bioartificial kidney. Hollow fibers were prepared from polyacrylonitrile PAN, polysulfonepolyvinylpyrollidinone PVP blend PSU and polyacrylonitrileNvinylpyrollidinone copolymer PANNVP. Hollow fibers with smaller and larger diameters were prepared so that the smaller fitted into the larger, with a distance of 50–100 μm in between. The following material combinations as outer and inner fiber were applied: PANPAN; PSUPSU, PSUPANNVP. Madin–Darby kidney epithelial cells MDCK were seeded in the interfiber space and cultured for a period up to 14 days. Light, scanning, and transmission electron microscopy were used to follow the adhesion and growth of cells, and to characterize their morphology. As a result, we found that MDCK cells were able to grow in the interfiber space in mono and multilayers without signs of systemic degeneration. Comparison of the different materials showed that PAN and PANNVP provided the best growth conditions, indicated by a tight attachment of cells on hollow fiber membrane, and subsequent proliferation and development of structural elements of normal epithelia, such as tight junctions and microvilli. In conclusion, the fiberinfiber design seems to be an interesting system for the construction of a bioartificial kidney. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 65A: 144–157, 2003

Abstract. To investigate the host-cell response to infection with the obligate intracellular pathogen Toxoplasma gondii, the transcriptional profiles of infected and uninfected human fibroblasts (HFF) were determined by hybridization to gene arrays representing nearly 600 genes. Transcripts that displayed a greater than five-fold increase in level relative to uninfected controls were also examined by RT-PCR and Northern analysis, resulting in the identification of 13 genes that were strongly up-regulated after infection with T. gondii. Comparisons with the transcriptional profiles of fibroblasts infected with Salmonella typhimurium and Chlamydia trachomatis allowed the identification of genes which are specifically induced in T. gondii-infected cells. While most of the up-regulated genes were induced on infection with all three pathogens, the genes for the transferrin receptor and MacMARCKS were up-regulated in Toxoplasma-infected fibroblasts only. Expression of the transferrin receptor protein was examined by Western analysis and found to be specifically elevated in Toxoplasma-infected fibroblasts. Genes which are specifically induced in T. gondii-infected cells are particularly interesting for further studies, since they might be used to dissect specific interactions of this pathogenic parasite with its host cell.

In this study, rat bone marrow cells RBM were used to evaluate two biodegradable calcium phosphate bone cements and bioactive calcium phosphate ceramics. The substances investigated were: two novel calcium phosphate cements, Biocement F and Biocement H, tricalcium phosphate TCP, surfacemodified alphatricalcium phosphate TCP s and a rapid resorbable calcium phosphate ceramic consisting of CaKPO4sample code R5. RBM cells were cultured on discshaped test substrates for 14 days. The culture medium was changed daily and also examined for calcium, phosphate, and potassium concentrations. Specimens were evaluated using light microscopy, and morphometry of the cellcovered substrate surface, scanning electron microscopy, and energy dispersive Xray analysis and morphometry of the cellcovered substrate surface. Areas of mineralization were identified by tetracyline labeling. Except for R 5, rat bonemarrow cells attached and grew on all substrate surfaces. Of the different calcium phosphate materials tested, TCP and TCP s facilitated osteoblast growth and extracellular matrix elaboration to the highest degree, followed by Biocements H and F. The inhibition of cell growth encountered with R 5 seems to be related to its high phosphate and potassium ion release. © 2000 John Wiley & Sons, Inc. J Biomed Mater Res, 52, 498–508, 2000.

Microsporidia are intracellular organisms of increasing importance as opportunistic pathogens in immunocompromised patients. Host cells are infected by the extrusion and injection of polar tubes located within spores. The spore is surrounded by a rigid spore wall which, in addition to providing mechanical resistance, might be involved in host cell recognition and initiation of the infection process. A 51-kDa outer spore wall protein was identified in Encephalitozoon cuniculi with the aid of a monoclonal antibody, and the corresponding gene, SWP1, was cloned by immunoscreening of a cDNA expression library. The cDNA encodes a protein of 450 amino acids which displays no significant similarities to known proteins in databases. The carboxy-terminal region consists of five tandemly arranged glycine- and serine-rich repetitive elements. SWP1 is a single-copy gene that is also present in the genomes of Encephalitozoon intestinalis and Encephalitozoon hellem as demonstrated by Southern analysis. Indirect immunofluorescence and immunoelectron microscopy revealed that SWP1 is differentially expressed during the infection cycle. The protein is absent in replicative meronts until 24 h postinfection, and its expression is first induced in early sporonts at a time when organisms translocate from the periphery to the center of the parasitophorous vacuole. Expression of SWP1 appears to be regulated at the mRNA level, as was shown by reverse transcriptase PCR analysis. Further identification and characterization of stage-specific genes might help to unravel the complex intracellular differentiation process of microsporidia.

Triplet−triplet energy transfer among peridinin molecules in peridinin−chlorophyll−protein (PCP) complexes from two different dinoflagellate species is quantitatively evaluated by the use of the optically detected magnetic resonance technique supplemented by triplet-state decay rate measurements. The two complexes are related by a dimer−monomer relationship in the sense that the four peridinins−one chlorophyll cluster of the Heterocapsa pygmeae PCP (H−PCP) is a copy of the two clusters contained in the larger protein Amphidinium carterae PCP (A−PCP), which are related by a local 2-fold symmetry axis. The system is conveniently discussed as a multistate Frenkel exciton system performing stochastic jumps from one exciton state to another. The rate of triplet−triplet energy exchange among peridinin molecules is obtained through the simulation of the spectral line shapes of optically detected magnetic resonance in zero field. Measurements were collected in a range of temperatures between 2 and 40 K and supplemented by the determination of the decay rate of the triplet to ground state in the same temperature range. The latter is of the order of 0.005 MHz and is relevant in determining the line shapes, especially at the lowest temperatures where the exchange rates are low. Exchange rates within the four-member peridinin cluster of H−PCP exactly match those within each of the two clusters of A−PCP and span a range from 0 to 20 MHz for the uphill rate and from 10 to 300 MHz for the downhill rate, corresponding to an energy difference of 41 cm^-1. The intercluster exchange rate in A−PCP goes from 0 to 12 MHz uphill and from 0.05 to 30 MHz downhill, with an energy difference of only 12.5 cm^-1. The kinetics conform to phonon-stimulated radiationless transition theory, and coupling parameters and reorganization energies are evaluated and discussed.

Abstract: · Background: A 32 year-old male patient had a 6-week history of left-sided proptosis. Computer tomography revealed a 16×15×15 mm smooth and well-defined mass between the optic nerve and the medial and superior rectus muscles in the left orbit. · Methods: The tumour was excised via a cranio-medial orbitotomy approach. · Results: Histopathological examination, immunohistochemistry and electron microscopy findings were consistent with an alveolar soft part sarcoma. Immunohistochemical staining showed positive immunoreactivity for neurone-specific enolase, vimentin, p53 (30%), p21 (10%) and cyclin D1 (20%), and negative immunoreactivity for CD45, cytokeratins, S-100 protein, glial fibrillary acidic protein, synaptophysin, chromogranin, calcitonin, serotonin, thyreoglobulin, desmin, myosin, actin, HMB-45, pRB, p16 and BCL-2. The growth fraction of the tumour cells was 3%. At examination 4 years after surgical excision, there was no evidence of local recurrence or for metastases. · Conclusion: Alveolar soft part sarcoma of the orbit is a rare malignant tumour best controlled by surgery. The unpredictable behaviour of these neoplasms, however, indicates the need for long-term follow-up.

The prerequisite for the development of a biohybrid artificial kidney, is a substrate for confluent growth of renal cells forming an epithelial monolayer without any leaks. Conventional cell culture supports cannot be adapted for this purpose, because they lack adequate mechanical properties and thermal stability. From two suitable materials, polysulfone and polyacrylonitrile, two permeable polymeric membranes have been produced that were, according to ISO 10993-5, not cytotoxic. Cloned Madin Darby Canine Kidney (MDCK) cells (an established renal cell line) were cultured on the surface of the plastic materials, and on conventional cell culture supports. With all materials, assays of mitochondrial and lactate dyhydrogenases exhibited similar proliferation and the viability of the MDCK cells. Transmission electron microscopy showed the expression of a normal morphology of kidney tubular cells. Perfect barrier function, consequent on the formation of intercellular junctions in a confluent tight epithelium, was visualized in electron micrographs, and quantified by measurement of the transepithelial resistance. The uniformity of the cells grown was demonstrated in samples by electron microscopy and in the whole epithelium by intravital impedance analysis. It was concluded that polymeric membranes produced from polysulfone or polyacrylonitrile are appropriate substrates in the design of biohybrid kidney devices. © 1998 Kluwer Academic Publishers

Acute intermittent porphyria (AIP) is a low-penetrant, autosomal dominant disorder caused by decreased activity of hydroxymethylbilane synthase (HMBS; MIM 176 000), the third enzyme in the heme biosynthetic pathway. We report the first molecular analysis of HMBS gene mutations in classical AIP patients of German origin. The HMBS gene of 5 German AIP patients was analysed by DGGE-screening and direct sequencing of amplified genomic DNA. Five different mutations including four novel mutations were found. Three of them are single base substitutions that affected exon 3 (R16C), exon 10 (V202L), and intron 13 (T to A, IVS13+2) The two remaining mutations are frameshifts which produce a stop codon (del GA in exon 6 and insA in exon 14). These mutations are likely to be responsible for the decrease in HMBS activity found in both erythrocytes and non-erythroid cell lines (lymphocytes). Our results demonstrate the allelic heterogeneity of HMBS mutations in AIP patients of German origin.

Abstract: There is evidence that not only the immune status, but also the genetic predisposition of certain hosts influence the clinical outcome of Toxoplasma gondii infection. By far the majority of our knowledge on genetic and immunological mechanisms involved in control of T. gondii infection has been obtained by studying mouse models, which in terms of clinical outcome of infection differ considerably from humans. Rats which show a rather similar course of infection in comparison to humans have not so far been investigated for effects of genetic differences on course of the infection. In this study we show that, like mice, different strains of rats exhibit a remarkable variation in the number of brain cysts arising from chronic infection. LEW rats seem to be highly resistant to cyst formation, in contrast to F344 rats that are susceptible. In addition, F344 rats express high numbers of γδ T cells during the acute phase of infection, whereas LEW rats express elevated but comparably low numbers of γδ T cells. The RT1 (rat MHC) haplotypes of both strains are identical in the RT1A and RT1B/D regions, which encode the restriction elements for conventional peptide antigens. Consequently, rat strain-specific differences may be useful to define MHC-independent mechanisms of resistance against T. gondii, which may also act in humans.

Abstract: Intracellular microorganisms have to rely on the integrity of their host cells to persist. We, therefore, investigated the effect of infections with different Toxoplasma gondii strains on apoptosis of human-derived HL-60 cells at the single cell level. Infection with either mouse-avirulent (NTE strain) or virulent parasites (RH strain) did not induce apoptosis of HL-60 cells as compared to uninfected controls. In contrast, treatment with actinomycin D (act D) led to apoptosis in 15–25% of the cells. However, concomitant infection with T. gondii clearly abrogated act D-induced apoptosis. This was especially apparent in those host cells that were actually infected; in these parasite-positive cells the rate of apoptosis decreased by 82.8±4.3% (mean±SEM, P=0.017, Student's t-test) and 91.7±3.4% (P=0.024) after infection with either the NTE or the RH strain, respectively. Inhibition of host cell apoptosis was similarly observed in cells which had been invaded by UV-irradiated, non-replicating parasites (P=0.001, Student's t-test). However, incubation with heat-killed parasites or T. gondii lysates did not abrogate act D-induced apoptosis. In conclusion, inhibition of apoptosis by living, but not necessarily replicating T. gondii may facilitate parasite survival and persistence within its host cell.

Lectin-binding studies demonstrated the presence of a 68-kDa glycoprotein in tachyzoites ofToxoplasma gondii harvested from P388D1 macrophage cell cultures but not in tachyzoites maintained in peritoneal cavities of NMRI mice. This protein was identified as the embryonic protein fetuin that regularly is contained in fetal calf serum, a component of cell-culture media. Uptake of fetuin byT. gondii was demonstrated by intracellular localization of this protein. As shown by latex agglutination and immunofluorescence, no specific binding of fetuin to the parasite's surface was detected. Using affinity chromatography of fetuin-agarose, it was demonstrated that fetuin bound specifically to a 15-kDa antigen of tachyzoites. As revealed by inhibition studies with sialic acid and the lectinSambucus nigra agglutinin, the 15-kDa protein probably recognized glycan structures of fetuin.

Summary This study examined effects of bone bonding and nonbonding implants on parameters associated with matrix vesicle-mediated primary bone formation, matrix vesicle alkaline phosphatase and phospholipase A2 specific activities, and phosphatidylserine content. Tibia marrow ablation followed by implantation of KG-Cera, Mina 13 (bonding), KGy-213, or M 8/1 (nonbonding) was used as the experimental model. Postsurgery, matrix vesicle-enriched microsomes (MVEM) were isolated from implanted and contralateral limbs. MVEM alkaline phosphatase and phospholipase A2 were stimulated adjacent to bonding implants with similar, though reduced, effects contralaterally. Alkaline phosphatase exhibited slight stimulation in nonbonding tissue; phospholipase A2 was inhibited or unchanged in treated and contralateral limbs. Phosphatidylserine content of MVEM was differentially affected by the implant materials. Thus, MVEM are modulated by implant materials locally and systemically. The data demonstrate that the model is a biologically relevant diagnostic for assessing the tissue/implant interface, primary calcification is affected by implant materials, and implant-specific effects are detected in the contralateral unimplanted limb.

Natural coral consisting of calcium carbonate was investigated after the implantation into the cortex and marrow cavity of the rat femur in order to study the substitution by bone, soft tissue and bone marrow. The time intervals were 7, 14, 21 and 28 days and the tissue reaction was morphometrically determined. The absorption of coralline substance seemed to be locally enhanced by osteoclasts and otherwise due to dissolution by interstitial fluid. The development of bone was predominant in the marrow space after 7 and 14 days postoperatively. At the later stages, the development of bone was more pronounced in the cortex and reduced in the marrow cavity. Von Kossa staining for calcium-containing material revealed small seams of mineral at the coralline surface, suggesting that these structures exert some influence on the deposition of mineral. Soft tissue was replaced in the marrow cavity by a regenerate of hemopoietic tissue. Already after 28 days the tissues replacing the natural coral implant were highly organized in order to restore the original structures and functions.

The effect of three different titanium plasma flame spray coatings on the tensile strength and the effect of macrostructures on the torsional shear strength of the bone implant interface was studied. Titanium cylinders, of 8 mm length and 4 mm diameter, were implanted into distal rabbit femurs. For tensile testing, two porous titanium plasma flame spray coatings, Plasmapore®, fine-grain Plasmapore®, 1 dense, unporous coating, Plasmapore® fine on cylinders with axial grooves, and corundum blasted specimens as control group were used. For torsional loading smooth, and macrostructured cylinders with axial grooves, both with Plasmapore® fine-coating, were used. After 168 days the implant-bone interface was biomechanically tested. A tensile test and a torsional shear test was performed. The results indicated, that the titanium plasma flame spray coatings did not differ in their tensile interface strength, but yielded a stronger interface as sandblasted surfaces and that the macrostructures did not influence the torsional shear strength.

The early responses of host and hydroxyapatite/ß-tricalciumphosphate (HA-TCP) porous ceramic implants were studied using light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) at 3, 7, 14, 21, and 28 days after implantation into the femur of rats. Micropores (<5 µm) and macropores of the implant surface provided effective structures for anchoring of various tissue components. Mineralization started directly on the implant surface and was observed in macropores and micropores, suggesting bone-bonding by epitaxis. Bone-bonding was observed with and without an amorphous intervening interface layer. The composition of this layer and the mechanisms guiding its production are not yet fully understood. Extracellular matrix filled up the clefts between HA-TCP crystal grain clusters. These processes contributed to the mechanical stabilization of the interface. Slight changes of implant grain surface morphology were observed which were explained by leaching of impurities, such as TCP and/or by dissolution acting on single grains. Diameters of pores and HA-TCP grains did not change in a period up to 28 days, which seems to be related to the relatively short periods of insertion and the material properties. Leaching and degradation were observed and loose particles of implant origin were phagocytosed by macrophages and multinuclear giant cells which dominated at non-bonding interfaces.

Since the first investigations made by Wolff, it has been known that bone adapts to mechanical load. The mechanisms which guide the reaction of osteoblasts and osteoclasts to load are still insufficiently known. In situ hybridization (ISH) allows the detection of intracellular gene transcripts. Therefore, the ISH technique was further developed to allow the detection of pro-alpha 1 (I) collagen gene transcripts on undecalcified bone surfaces. Additionally, this new technique was combined with the tartrate resistant acid phosphatase technique. The combination of the two methods allows the detection of forming and resorbing cells on the same undecalcified bone surface. In addition, a new animal model was developed to study the reaction of bone to mechanical load. This model mimics the situation of bone implants (e.g. hip prosthese), which is a static situation which is dynamically loaded by the action of the patient.

Steady-state solar and infrared radiation heat exchange in the cavity receiver of a solar tower is presented in the form of a mathematical model. The inside cavity walls consist partly of tubes containing air as a heat carrier. The distribution of tube wall temperatures, air temperature, and the heat flux density along the tubes are calculated at different times of day for different seasons. The efficiency of solar and infrared radiation exchange in the cavity is determined, as well as cosine losses of the heliostat Held. The receiver layout is based on maximum gain on 21 June, 12 O'clock noon.With a fixed value of 800 °C for the air outlet temperature and a constant air inlet temperature of 352 °C, the air mass flow-rate must be controlled within a wide range in order to compensate for the varying irradiation conditions. On 21 June, e.g., during an operation time between 9 a.m. and 3 p.m. the range is between 70 and 100% while operation between 6 a.m. and 6 p.m. requires a range of 15 to 100%.The reduced irradiance in December aggravates the problems of partial load characteristics.

Abstract:  Toxoplasma gondii isolates can be classified into mouse-virulent and -avirulent strains. Since the major surface antigen of Toxoplasma gondii, SAG1, has been shown to be important for the invasion process and might thus be involved in mouse virulence as well, we analyzed the corresponding gene of mouse-virulent and -avirulent strains. In addition to eight mismatches, mouse-virulent strains harbored five copies of an upstream 27-bp repeat in the promotor region of SAG1 as compared with four copies in avirulent strains. Reverse-transcriptase polymerase chain reaction revealed that SAG1 expression levels in the mouse-virulent T. gondii strains were at least 4-fold those in the avirulent strains. Since SAG1 seems to mediate invasion, it is suggested that the possibly higher steady-state expression of SAG1 in mouse-virulent strains of T. gondii is associated with virulence and facilitates faster invasion by these strains in comparison with avirulent strains.

We previously reported the in vitro analysis of stage differentiation of Toxoplasma gondii in murine bone marrow-derived macrophages. The purpose of this study was to generate monoclonal rat antibodies that might be suitable for investigating tachyzoite-bradyzoite interconversion in vivo with the murine model. Immunization of Fischer rats with cysts of T. gondii NTE resulted in the generation of seven monoclonal antibodies of the immunoglobulin G2a, G2b, or M isotype, which were further characterized by the immunoblot technique, immunofluorescence assay, immunohistology, and immunoelectron microscopy. Immunoblots demonstrated specific reactivity of five monoclonal antibodies with proteins with molecular masses of 40, 52, 55, 60, 64, 65, and 115 kDa. One antibody (CC2) appeared to recognize a differently expressed antigen depending on the parasite stage, reacting with a 40-kDa molecule in tachyzoites and a 115-kDa antigen in bradyzoites and oocysts. Several other monoclonal antibodies were shown to be stage specific and to react in immunofluorescence assays or in immunoblots with either tachyzoites or bradyzoites. Kinetics of stage conversion in vitro could be monitored by immunofluorescence with two of these monoclonal antibodies. Preliminary immunohistological investigations of tissue sections from infected mice demonstrated the possible usefulness of these monoclonal antibodies for future in vivo studies on stage differentiation of T. gondii in the murine system.

Temporal and spatial patterns of osteoblast activation around ß-TCP particles implanted into bone were analyzed by in situhybridization with digoxygenin-labeled procollagen a1(I) RNA probes. ß-TCP particles (150–300 µm in diameter) were implanted into rat tibiae, and specimens were collected 3, 5, 7, 14, and 28 days after operation. Activated osteoblasts displayed intense procollagen a1(I) RNA specific labeling. At day 3, osteoblasts lining pre-existing trabeculae in places showed a specific signal. Additionally, scattered activated cells compatible with preosteoblasts also were observed in the vicinity of the trabeculae among red blood cells that filled the space between ß-TCP particles. Osteoblast activation on the surface of ß-TCP rarely was observed. At days 5 and 7, osteoblast activation and bone formation advanced centripetally. At the forefront of bone formation positive cells were scattered in the blood cell clots, and some of the positive cells colonized forming new bone matrix. Formation of new bone did not always begin at the surface of ß-TCP. At day 14, most of the ß-TCP particles were tightly associated with newly formed bone, and the number of positive osteoblasts was reduced. At day 28, absorption of the newly formed bone and the ß-TCP by multinuclear cells was sporadically demonstrated. Such cells often were accompanied by active osteoblasts, suggesting early bone remodeling. In conclusion, in situhybridization with procollagen a1(I) was employed to demonstrate precisely the mode of recruitment of bone cell precursors. ß-TCP does not positively guide collagen I expressing bone cells along its surface. It has no apparent effects on bone regeneration. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 39, 71–76, 1998.

Osteoblast activation after implantation of two kinds of surface-active material in bone was investigated chronologically using in situhybridization with digoxygenin-labeled procollagen a1(I) complementary RNA probe. The bioactive materials used were hydroxyapatite (HA) and apatite- and wollastonite-containing glass-ceramic (A-W GC). A hole was drilled bilaterally in the distal epiphysis of rabbit femurs with subsequent implantation of HA or A-W GC cylinders in a press-fit manner. Specimens were collected at 3, 7, 14, and 28 days after operation and decalcified. Then the undecalcified implant cores were pushed out of the hole without causing damage to the bony side of the interface. In situhybridization documented no qualitative differences in the expression of procollagen a1(I) RNA between HA and A-W GC. Few osteoblasts at the bone-material interface showed a specific signal at day 3, whereas many osteoblasts were positive around the materials at days 7 and 14, indicative of active new bone formation. The positive osteoblasts seemed to originate from preexisting trabeculae and lined the trabeculae, newly formed bone, and material surface. At day 28, many osteoblasts lining material-surrounding bone were negative, whereas those in remodeling canals were positive, suggesting that the bone was in the remodeling stage after bone formation. These findings were comparable to those with ß-tricalcium phosphate in a previous study, thus suggesting osteoconductive bone formation on HA and A-W GC. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 39, 1–8, 1998.

Thermal-conductivity measurements are reported for the new refrigerants R134a, R152a und R123. Transient hot-wire experiments were performed which cover both the liquid and vapor states at temperatures and pressures ranging from?=-20°C to 90°C and fromp=0.1 bar to 60 bar respectively. The results are correlated with density and temperature. In addition temperature dependent correlations are presented for (i) saturated liquid, (ii) saturated vapor, (iii) ideal gas (which equals approximately vapor state at ambient pressure). Finally the results are compared with data from the literature and also with the thermal conductivities of R12 and R11.

Maßgeschneiderte Perfluoremulsionen erfüllen bereits viele Anforderungen an Blutersatzmittel. Ihre Weiterentwicklung ist eine anspruchsvolle wissenschaftliche Aufgabe für Chemie und Medizin. Maßgeschneiderte Perfluoremulsionen erfüllen bereits viele Anforderungen an Blutersatzmittel. Ihre Weiterentwicklung ist eine anspruchsvolle wissenschaftliche Aufgabe für die Chemie und Medizin.

Der bittere Geschmack von Lupinenalkaloiden läßt sich im Wasser im Falle von Spartein noch im ppm-Bereich sensorisch nachweisen und nimmt über D-Lupanin-Perchlorat, Lupinin, Isolupanin, Hydroxylupanin ab. Die Quellfähigkeit von Lupinensamen hat artenunterschiedliche Charakteristika. Die Quellgeschwindigkeit ist inL. albusetwas geringer als inL. mutabilis. Die Wasseraufnahme nimmt in heißem Wasser ab, die Quellgeschwindigkeit zu. Zur häuslichen Entbitterung empfiehlt es sich, die ganzen Lupinensamen eine halbe Stunde zu kochen und drei Tage in fließendem Wasser zu entbittern. Der isoelektrische Punkt des Eiweißes vonL. mutabilisliegt zwischen pH 4 und 4,5. The bitter taste of lupin alkaloids can be sensorially detected in water within Ppm-range. The strength of the taste diminishes as follows: sparteine, D-Lupanin-Perchlorate, lupinine, isolupinine and hydroxylupanine. The swelling capacity of lupin seeds presents different characteristics according to the species. The swelling rapidity is inL. albussomehow inferior to that ofL. mutabilis. The absorption of water decreases in hot water, and the swelling rapidity increases. For domestic debittering it is recommended to cook whole lupin seeds during half an hour and to debitter them for 3 days in flowing water. The isoelectric point of the protein ofL. mutabilislies between pH 4 and 4.5.

20 Personen erhielten über vier Wochen 58,9±9,6 g Mehl vonLupinus albus. Alle Personen vertrugen das Süßlupinenmehl gut. Es konnten keine nennenswerten Veränderungen von Hämoglobin, Hämatokrit, Gesamtprotein, Harnstoff, Bilirubin und SGOT im Blut festgestellt werden. Die Lupine kann mit zur Eiweißversorgung in der menschlichen Ernährung beitragen, wenn sichergestellt ist, daß1.der Alkaloidgehalt im Samen nicht über 0,02 % liegt und2.der Samen frei von Sekundärpilzen ist, die eine Lupinose bewirken können. Lupinus albusflour doses of 58.9±9.6 g have been given to 20 persons. This sweet lupine flour has been digestible without complications in all cases. There have been no significant changes of hemoglobine, hematocrite, total protein, urea, bilirubine, and SGOT in the blood. So the lupine may be used for improvement of protein supply in men under the criteria that(1)the alkaloid content of the seed does not exceed 0.02%,(2)the seed itself contains no secondary fungi which may cause a lupinosis.

20 Prüfpersonen beurteilten über vier Wochen 48 verschiedene Speisen, die mit dem Mehl vonLupinus albusangereichert wurden. Die Speisen und Produkte mit Lupinenzusatz wurden mit der korrespondierenden konventionellen Speise geschmacklich gleich bewertet. Besonders günstig liegen die Teigwaren in der Beurteilung. Es empfiehlt sich zukünftig in Peru, einen Lupinenzusatz in Brot, Kekse, Soßen, Suppen und Nudeln einzuarbeiten. Ein zeitlicher Einfluß auf die Beurteilung fand nicht statt. 48 different dishes enriched withlupinus albusflour have been tested by 20 persons. The test duration has been 4 weeks. Meals and products with lupine admixtures have been judged equally with concern to corresponding conventional dishes. Farinaceous products had the best test results. Therefore, it is recommended for Peru to add lupine flour when producing bread, biscuits, sauces, soups, and noodles (maccaronis etc.). The test time had no influence to the test results.

Intravenous injection of the light lanthanon praseodymium nitrate (10 mg/kg) into rats causes a marked liver toxicity which becomes manifest in hypoglycemia, inhibition of RNA and protein synthesis and accumulation of fat in liver tissue. All these effects can be nearly abolished by pretreating rats with a small dose (5 mg/kg) of the same lanthanon. This is neither due to a decreased uptake into the liver nor to an increased excretion rate of the lanthanon. It is assumed that the pretreatment may increase unspecific binding sites or reversibly block them, thus protecting the organism from the irreversible lethal effect.