The effect of pre-operative blood withdrawal, with or without sequestration, on allogeneic blood product requirements.

UNLABELLED: A common effect of autologous blood withdrawal before cardiopulmonary bypass (CPB) is a decrease in haematocrit (Hct) and haemoglobin (Hb) content. A refinement of this technique is autologous blood withdrawal with the sequestration of platelet rich plasma (PRP) and red blood cells (RBCs). METHODS: One hundred and four patients were included in a randomized study stratified into three groups: the autologous blood withdrawal group (Group 1), the autologous blood withdrawal group with blood loss sequestration (Group 2) and the control group (Control group). In Group 1, the amount of withdrawn blood was transfused after CPB. In Group 2, the RBCs were transfused immediately after sequestration and the PRP was transfused after the termination of CPB. In the Control group, no autologous blood withdrawal was employed. The following variables were analysed: blood loss, blood products transfusion, fluid transfusion, diuresis, haematological and coagulation data and the duration of the operation and intensive care unit stay. RESULTS: We found no significant differences in peri-operative blood loss and transfused blood products among the three groups. There was a trend towards a lower amount of transfused fresh frozen plasma (FFP) for Group 1 (p =0.057) in the operation room (OR). The use of plasma expanders post-CPB was significantly higher in the Control group (p=0.024). RBCs coming from the auto-transfusion device were, for Group 1, significantly lower (p=0.007). The Hb and Hct values in Group 1, at start and end of CPB, were significantly lower (p=0.023-0.003 / 0.001-0.001, respectively). All other parameters were not significantly different. CONCLUSION: there were no significant differences between the study groups. This randomized trial shows that, although sequestration immediately after autologous blood withdrawal has no added value, autologous blood withdrawal in patients with a normal pre-operative Hb and Hct is simple, inexpensive and allows for autologous blood transfusion.

Breakdown of the x-ray resonant magnetic scattering signal during intense pulses of extreme ultraviolet free-electron-laser radiation.

We present results of single-shot resonant magnetic scattering experiments of Co/Pt multilayer systems using 100 fs long ultraintense pulses from an extreme ultraviolet (XUV) free-electron laser. An x-ray-induced breakdown of the resonant magnetic scattering channel during the pulse duration is observed at fluences of 5 J/cm(2). Simultaneously, the speckle contrast of the high-fluence scattering pattern is significantly reduced. We performed simulations of the nonequilibrium evolution of the Co/Pt multilayer system during the XUV pulse duration. We find that the electronic state of the sample is strongly perturbed during the first few femtoseconds of exposure leading to an ultrafast quenching of the resonant magnetic scattering mechanism.

Somites in zebrafish doubly mutant for knypek and trilobite form without internal mesenchymal cells or compaction.

In vertebrates, paraxial mesoderm is partitioned into repeating units called somites. It is thought that the mechanical forces arising from compaction of the presumptive internal cells of prospective somites cause them to detach from the unsegmented presomitic mesoderm [1-3]. To determine how prospective somites physically segregate from each other, we used time-lapse microscopy to analyze the mechanics underlying early somitogenesis in wild-type zebrafish and in the mutants trilobite(m209) (tri), knypek(m119) (kny), and kny;tri, which are defective in convergent extension during gastrulation. Formation of somite boundaries in all of these embryos involved segregation, local alignment, and cell-shape changes of presumptive epitheloid border cells along nascent intersomitic boundaries. Although kny;tri somites formed without convergence of the presomitic mesoderm and were composed of only two cells in their anteroposterior (AP) dimension, they still exhibited AP intrasegmental polarity. Furthermore, morphogenesis of somite boundaries in these embryos proceeded in a manner similar to that in wild-type embryos. Thus, intersomitic boundary formation in zebrafish involves short-range movements of presumptive border cells that do not require mechanical forces generated by internal cells or compaction of the presomitic mesoderm.

A dominant inhibitory mutant of the type II transforming growth factor beta receptor in the malignant progression of a cutaneous T-cell lymphoma.

In many cancers, inactivating mutations in both alleles of the transforming growth factor beta (TGF-beta) type 11 receptor (TbetaRII) gene occur and correlate with loss of sensitivity to TGF-beta. Here we describe a novel mechanism for loss of sensitivity to growth inhibition by TGF-beta in tumor development. Mac-1 cells, isolated from the blood of a patient with an indolent form of cutaneous T-cell lymphoma, express wild-type TbetaRII and are sensitive to TGF-beta. Mac-2A cells, clonally related to Mac-1 and isolated from a skin nodule of the same patient at a later, clinically aggressive stage of lymphoma, are resistant to TGF-beta. They express both the wild-type TbetaRII and a receptor with a single point mutation (Asp-404-Gly [D404G]) in the kinase domain (D404G-->TbetaRII); no TbetaRI or TbetaRII is found on the plasma membrane, suggesting that D404G-TbetaRII dominantly inhibits the function of the wild-type receptor by inhibiting its appearance on the plasma membrane. Indeed, inducible expression, under control of a tetracycline-regulated promoter, of D404G-TbetaRII in TGF-beta- sensitive Mac-1 cells as well as in Hep3B hepatoma cells results in resistance to TGF-beta and disappearance of cell surface TbetaRI and TbetaRII. Overexpression of wild-type TbetaRII in Mac-2A cells restores cell surface TbetaRI and TbetaRH and sensitivity to TGF-beta. The ability of the D404G-TbetaRH to dominantly inhibit function of wild-type TGF-beta receptors represents a new mechanism for loss of sensitivity to the growth-inhibitory functions of TGF-beta in tumor development.

Gastritis with valproate therapy.

We have identified ten children who developed gastritis after prolonged anticonvulsant therapy that included either valproic acid or divalproex sodium. Presenting symptoms were primarily feeding difficulties, including anorexia and refusal to eat. Vomiting was present in two thirds of the patients, with diarrhea, weight loss, and abdominal pain occurring less frequently. Occult blood in stool samples was a late development. All patients responded to therapy with H2-receptor antagonists, oral antacids, or both, with prolonged treatment often necessary to prevent relapse. Although gastrointestinal tract side effects are common with the initiation of valproate sodium therapy, feeding difficulties after long-term treatment are less common. Gastritis should be suspected in children receiving valproate therapy when feeding difficulties arise, particularly if the symptoms are persistent or recurrent.

S35 and derived parameters during extracorporeal circulation together with hemodilution and hypothermia in humans.

A new concept in monitoring systemic oxygenation that includes the effect of changes in oxyhemoglobin dissociation curve (ODC) has been introduced. Using the S35 (saturation of hemoglobin at PO2 = 35 mmHg), real arterial available oxygen content (CavlO2) can be calculated being the maximum amount of oxygen that can be extracted from hemoglobin before oxygen diffusion into tissue becomes compromised and oxygen uptake (VO2) may decrease. The relation between VO2 and CavlO2 expressed by the extraction ratio of the arterial available oxygen content (ERav) gives a realistic indices of oxygen supply in relation to oxygen consumption. In the present study, during extracorporeal circulation (ECC), a severe shift to the left of the ODC could be observed. THe classic parameters for monitoring systemic oxygenation as mixed venous saturation (Sv-O2) and extraction ratio (ER) did not change. The S35 increased because of the shift to the left of the ODC with consequent decrease in CavlO2. The ERav reached critical values during ECC together with hemodilution and hypothermia. A severe decrease in mixed venous PO2 (Pv-O2) was also observed. The authors conclude that besides Pv-O2, the S35, the CavlO2 and especially the ERav are of value in monitoring the systemic oxygenation during hypothermic ECC.

Endstation for ultrafast magnetic scattering experiments at the free-electron laser in Hamburg.

An endstation for pump-probe small-angle X-ray scattering (SAXS) experiments at the free-electron laser in Hamburg (FLASH) is presented. The endstation houses a solid-state absorber, optical incoupling for pump-probe experiments, time zero measurement, sample chamber, and detection unit. It can be used at all FLASH beamlines in the whole photon energy range offered by FLASH. The capabilities of the setup are demonstrated by showing the results of resonant magnetic SAXS measurements on cobalt-platinum multilayer samples grown on freestanding Si(3)N(4) membranes and pump-laser-induced grid structures in multilayer samples.

Ultrafast optical demagnetization manipulates nanoscale spin structure in domain walls.

During ultrafast demagnetization of a magnetically ordered solid, angular momentum has to be transferred between the spins, electrons, and phonons in the system on femto- and picosecond timescales. Although the intrinsic spin-transfer mechanisms are intensely debated, additional extrinsic mechanisms arising due to nanoscale heterogeneity have only recently entered the discussion. Here we use femtosecond X-ray pulses from a free-electron laser to study thin film samples with magnetic domain patterns. We observe an infrared-pump-induced change of the spin structure within the domain walls on the sub-picosecond timescale. This domain-topography-dependent contribution connects the intrinsic demagnetization process in each domain with spin-transport processes across the domain walls, demonstrating the importance of spin-dependent electron transport between differently magnetized regions as an ultrafast demagnetization channel. This pathway exists independent from structural inhomogeneities such as chemical interfaces, and gives rise to an ultrafast spatially varying response to optical pump pulses.

Injected mRNA does not increase protein synthesis in unfertilized, fertilized, or ammonia-activated sea urchin eggs.

We have investigated whether the rate of protein synthesis in unfertilized and fertilization-activated sea urchin eggs is limited by the availability of mRNA by injecting eggs, zygotes, and ammonia-activated eggs with globin mRNA. Message-injected and buffer-injected cells were labeled with radioactive amino acids and the proteins separated on a polyacrylamide gel. The relative amounts of newly synthesized globin and endogenous proteins were obtained by scanning the gel fluorograph. Globin mRNA is translated poorly in Strongylocentrotus droebachiensis eggs and does not significantly increase or decrease endogenous protein synthesis. In zygotes and ammonia-activated eggs, however, globin mRNA is translated well and appears to compete with endogenous mRNAs for the limiting component of the translational machinery as it is released. Our results are consistent with the hypothesis that either ribosomes or recruitment factors are gradually activated after fertilization or ammonia treatment, that such components are the rate-limiting factor, and that they impart the typical sigmoidal increase in protein synthesis rate observed in fertilized eggs before the first cleavage.

Cell-free translation systems prepared from starfish oocytes faithfully reflect in vivo activity; mRNA and initiation factors stimulate supernatants from immature oocytes.

Meiotic maturation stimulates a change in the translation of stored mRNAs: mRNAs encoding proteins needed for growth of oocytes are translated before meiotic maturation, whereas those encoding proteins required for cleavage are translated after meiotic maturation. Studies of translational regulation during meiotic maturation have been limited by the lack of translationally active cell-free supernatants. Starfish oocytes are ideal for preparing cell-free translation systems because experimental application of the hormone 1-methyladenine induces their maturation, synchronizing meiosis. We have prepared such systems from both immature and mature oocytes of starfish. Changes in protein synthesis rates and the specificity of proteins synthesized in these cell-free translation supernatants mimic those seen in vivo. Supernatants both from immature and mature oocytes have a high capacity to initiate new translation because 90% of the proteins made are newly initiated from mRNAs. Cell-free supernatants from mature oocytes have a much higher rate of initiation of translation than those from immature oocytes and use the 43S preinitiation complexes more efficiently in initiation of translation. Similarly, we have shown that mRNAs and initiation factors are rate limiting in cell-free translation systems prepared from immature oocytes. In addition, cell-free translation systems prepared from immature oocytes are only slightly, if at all, inhibitory to cell-free translation systems from mature oocytes. Thus, soluble inhibitors, if they exist, are rapidly converted by cell-free supernatants from mature oocytes. The similarities between translation in our starfish cell-free translation systems and in intact oocytes suggests that the cell-free translation systems will be useful tools for further studies of maturation events and translational control during meiosis.

Sea urchin egg and embryo ribosomes: differences in translational activity in a cell-free system.

To determine whether ribosomes have a role in the postfertilization activation of protein synthesis in sea urchin eggs, we measured the translational activity of ribosomes isolated from unfertilized eggs and embryos of Strongylocentrotus purpuratus. Numerous previous studies have indicated few if any differences in the activity of such ribosomes. However, by using improved physiological isolation and in vitro conditions, we have found important differences in the activities of egg and embryo ribosomes. Ribosomes obtained from blastula polyribosomes were active in translating reticulocyte mRNA in a ribosome-dependent cell-free translation system, whereas ribosomes obtained from unfertilized eggs became fully active only after a characteristic, reproducible delay of up to 15 min at 26 degrees C. The extent of this delay varied with incubation pH, but not with concentrations of K+, Mg2+, initiation factors, or mRNA. However, at incubation pH between 6.90 and 7.65, the egg ribosomes were always less active than blastula ribosomes.

Isolation and distribution of elongation factor 2 in eggs and embryos of sea urchins.

The subcellular distribution of elongation factor 2 (EF-2) in eggs and early embryos of the sea urchin, Strongylocentrotus purpuratus, was studied by employing the diphtheria toxin dependent ADP-ribosylation of EF-2. When egg and embryo homogenates were fractionated by sedimentation, EF-2 was found associated with a low-speed pellet containing yolk, nuclei, and mitochondria. It also sedimented at 80 S and 5 S. No significant amounts of EF-2 were found on polyribosomes. The 5S form of EF-2 probably represents a monomeric unit of the factor as EF-2 had a molecular weight of 95 000 on sodium dodecyl sulfate-polyacrylamide gels. EF-2 could only be isolated intact if soybean trypsin inhibitor or EGTA was present. The total amount of EF-2 was similar in eggs and embryos. However, the distributions of the factor between the various fractions were substantially different for eggs and embryos. Also, a marked difference in the physical association of EF-2 with material in the low-speed pellet occurred after fertilization. Specifically, in eggs, 23% of the EF-2 was associated with the low-speed pellet; in cleavage-stage embryos, only 11% of the EF-2 was associated with the pellet. In eggs, 65% of the EF-2 sedimented as 80 S; by the 16-cell stage, this amount decreased to 44%. Concomitantly, the amount of EF-2 in the 5S fraction increased from about 8% in eggs to 44% in the 16-cell embryos. In addition, Triton X-100 was required for the extraction of EF-2 from the low-speed pellet of eggs, but not of embryos.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical features of vascular thrombosis following varicella.

OBJECTIVE: To define the clinical characteristics, neuroimaging features, and outcome of five patients with post-primary varicella zoster virus infection hemiparesis and to offer a hypothesis to explain the predilection for the involvement of the cerebral vasculature in this condition. DESIGN: Patient series. SETTING: Five patients were treated during a 14-month period in a private pediatric neurology practice in a medium-size southwestern city. INTERVENTIONS: Steroids (two patients) and antiplatelet drugs (two patients). No observed effects of therapy. RESULTS: The onset of the hemiparesis occurred several weeks (mean, 5.4 weeks) following an episode of the chickenpox. Magnetic resonance imaging was more sensitive than computed tomography or angiography in demonstrating the area of involvement deep in the cerebral hemispheres. The prognosis was good regardless of the therapy administered, as all patients recovered completely or nearly completely. CONCLUSIONS: Primary varicella zoster virus infection with delayed-onset hemiparesis typically occurs approximately 6 weeks after primary varicella zoster virus infection. Magnetic resonance imaging is the most sensitive neuroimaging tool in these children. The prognosis is good, with recovery of function and no recurrences in our patients. The innervation of the carotid artery and the characteristics of the varicella zoster virus itself together provide the local and systemic factors that may trigger the vasculopathy responsible for this syndrome.

[Compression tests on the human hip joint (author's transl)]. / Druckbelastungsversuche an menschlichen Hüftgelenken.

Three human pelvises were subjected to static loading in the course of the experiments. The values determined for the elasticity modules lie between 2 and 4.5 kp/min2. The values range between 5 and 14 kp/mm2 if only the compacta is considered. The experiments show that the elasticity modules obtained at cross sections through the Os coxae are higher than those for sections through the hip joint and its immediate surroundings. Here the elasticity module reaches the minimum value of 0.77 kp/cm2 (Fig. 1, cross section No.2, Table 3). The highest breaking strain was 1045 kp (Pelvis II). The longitudinal contraction of the three pelvis was 26.6 mm on average. For the mean height of 27.2 cm for the specimens used, this means that the pelvis, as a system (with hip joint) can be reduced in length by about 10% before a fracture occurs under static load conditions.

Dual role of GdmH in producer immunity and secretion of the Staphylococcal lantibiotics gallidermin and epidermin.

The biosynthetic gene clusters of the staphylococcal lantibiotics epidermin and gallidermin are distinguished by the presence of the unique genes epiH and gdmH, respectively. They encode accessory factors for the ATP-binding cassette transporters that mediate secretion of the antimicrobial peptides. Here, we show that gdmH also contributes to immunity to gallidermin but not to nisin. gdmH alone affected susceptibility to gallidermin only moderately, but it led to a multiplication of the immunity level mediated by the FEG immunity genes when cloned together with the gdmT gene, suggesting a synergistic activity of the H and FEG systems. gdmH-related genes were identified in the genomes of several bacteria, indicating an involvement in further cellular functions.

Gastrulation in the sea urchin, Strongylocentrotus purpuratus, is disrupted by the small laminin peptides YIGSR and IKVAV.

Laminin is present on the apical and basolateral sides of epithelial cells of very early sea urchin blastulae. We investigated whether small laminin-peptides, known to have cell binding activities, alter the development of sea urchin embryos. The peptide YIGSR-NH2 (850 microM) and the peptide PA22-2 (5 microM), which contains the peptide sequence IKVAV (Tashiro et al., J. Biol. Chem. 264, 16174, 1989), typically blocked archenteron formation when added to the sea water soon after fertilization. At lower doses, the YIGSR peptide allowed invagination of the archenteron but blocked archenteron extension and differentiation and evagination of the feeding arms. The effect of YIGSR and PA22-2 peptides declined when added to progressively older stages until no effect was seen when added at the mesenchyme blastula stage (24 hours after fertilization). Control peptides GRGDS, YIGSE, and SHA22, a dodeca-peptide with a scrambled IKVAV sequence, had no effect on development. The YIGSK peptide containing a conserved amino acid modification had only a small effect on gastrulation. The results suggest that YIGSR and IKVAV peptides specifically disrupt cell/extracellular matrix interactions required for normal development of the archenteron and feeding arms. Our recent finding that YTGIR is at the cell binding site of the B1 chain of S. purpuratus laminin supports this conclusion. Evidently, laminin or other laminin-like molecules are among the many extracellular matrix components needed for the invagination and extension of the archenteron during the gastrulation movements of these embryos.

Polypeptides of nonpolyribosomal messenger ribonucleoprotein complexes of sea urchin eggs.

RNA competent in directing protein synthesis is sequestered in unfertilized sea urchin eggs as translationally quiescent, nonpolyribosomal, messenger ribonucleoprotein complexes (mRNPs). Following fertilization, these mRNPs are derepressed and actively translated, presumably due to changes in the mRNA-associated proteins and their interaction with the mRNA. We have isolated poly(A)-containing egg mRNPs free of contaminating monoribosomes and ribosomal subunits by chromatography on oligo(dT)-cellulose and identified their constituent proteins. Egg mRNPs isolated by using near physiological ionic conditions have 15-20 major proteins, most of which are in the molecular weight range of 40 000-100 000, and approximately 15-23 minor proteins in the 22 000-190 000 molecular range. The association of the proteins with poly(A)-containing mRNA is indicated by their greatly reduced retention on oligo(dT)-cellulose after pretreatment of the crude mRNP fraction with saturating amounts of poly(uridylic acid). Three of the proteins present in poly(A)-containing mRNPs from eggs, with molecular weights of 48 000, 67 000, and 140 000, were not detected in poly(A)-containing mRNPs derived from polyribosomes of hatched blastula-stage embryos. In addition, stoichiometric differences were found between some of the proteins associated with the two types of mRNP. The potential regulatory role of these proteins is discussed.

Maturation hormone induced an increase in the translational activity of starfish oocytes coincident with the phosphorylation of the mRNA cap binding protein, eIF-4E, and the activation of several kinases.

The stimulation of translation in starfish oocytes by the maturation hormone, 1-methyladenine (1-MA), requires the activation or mobilization of both initiation factors and mRNAs [Xu and Hille, Cell Regul. 1:1057, 1990]. We identify here the translational initiation complex, eIF-4F, and the guanine nucleotide exchange factor for eIF-2, eIF-2B, as the rate controlling components of protein synthesis in immature oocytes of the starfish, Pisaster orchraceus. Increased phosphorylation of eIF-4E, the cap binding subunit of the eIF-4F complex, is coincident with the initial increase in translational activity during maturation of these oocytes. Significantly, protein kinase C activity increased during oocyte maturation in parallel with the increase in eIF-4E phosphorylation and protein synthesis. An increase in the activities of cdc2 kinase and mitogen-activated myelin basic protein kinase (MBP kinase) similarly coincide with the increase in eIF-4E phosphorylation. However, neither cdc2 kinase nor MBP kinase phosphorylates eIF-4E in vitro. Casein kinase II activity does not change during oocyte maturation, and therefore, cannot be responsible for the activation of translation. Treatment of oocytes with phorbol 12-myristate 13-acetate, an activator of protein kinase C, for 30 min prior to the addition of 1-MA resulted in the inhibition of 1-MA-induced phosphorylation of eIF-4E, translational activation, and germinal vesicle breakdown. Therefore, protein kinase C may phosphorylate eIF-4E, after very early events of maturation. Another possibility is that eIF-4E is phosphorylated by an unknown kinase that is activated by the cascade of reactions stimulated by 1-MA. In conclusion, our results suggest a role for the phosphorylation of eIF-4E in the activation of translation during maturation, similar to translational regulation during the stimulation of growth in mammalian cells.

[The fight against hemolytic disease of the newborn-- an example of interdisciplinary cooperation]. / Die Bekämpfung des Morbus hämolyticus neonatorum--ein Beispiel interdisziplinärer Kooperation.

The practical proceeding used in checking anti-D-immunoprophylaxis, in monitoring carriers of antibodies during gravidity and in treating newborns is represented. Details of patients selecting by means of step by step prenatal diagnostics as well as technique and results of intrauterine transfusion are described. After the general introduction of anti-D-prophylaxis, the morbidity resulting from morbus haemolyticus could be reduced by 80% approximately. The survival rate of foeti intrauterinely transfused amounts to 49%.

[Carcinoid tumor with cystic liver metastases]. / Karzinoid mit zystischen Lebermetastasen.

Generally metastases of carcinoid tumours are pseudocystic in nearly 10% of the patients. In our case the guiding diagnostic importance of sonography and computed tomography could be proved. Results have to be completed by histologic findings and hormonal analysis (serotonin, 5-hydroxyindol acetic acid). - Morphological signs especially of the new imaging techniques are often a supposition for the modern therapy, e.g. the application of serotonin antagonists, local perfusion of cytostatic substances and if possible transplantation of the liver.