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Showing papers by "University of Kiel published in 1987"


Journal Article
TL;DR: A novel monocyte-derived neutrophil-activating peptide (MONAP) produced by lipopolysaccharide- and phorbol myristate acetate-stimulated human peripheral blood monocytes was purified by sequential ion exchange-high performance liquid chromatography, size exclusion HPLC, and reversed phase HPLC and found to be homogeneous.
Abstract: A novel monocyte-derived neutrophil-activating peptide (MONAP) produced by lipopolysaccharide- and phorbol myristate acetate-stimulated human peripheral blood monocytes was purified by sequential ion exchange-high performance liquid chromatography (HPLC), size exclusion HPLC, and reversed phase HPLC. Biologic activities of the purified cytokine were monitored by either an enzyme release assay or a chemotaxis assay, using peripheral human neutrophils. Purified MONAP was found to be homogeneous, giving a single peak on size-exclusion HPLC, reversed-phase HPLC, as well as a single 10-kDa band on silver-stained polyacrylamide gels. Purified MONAP stimulate human neutrophil chemotaxis at an estimated molarity of 5 x 10(-11) M. Half-maximal enzyme release of cytochalasin B pretreated neutrophils occurred at 2 to 3 x 10(-10) M, whereas superoxide anion production elicited by various concentrations of MONAP was found to be low. Isolated human peripheral monocytes, as well as human eosinophils, showed no chemotactic response to MONAP, indicating neutrophil specificity. MONAP activity was separated from thymocyte-stimulating activity by reversed-phase HPLC, indicating nonidentity with interleukin (IL)-1. This was further supported by heat resistance of MONAP, which is in contrast to the heat sensitivity of IL-1. In addition, IL-1 obtained as a by-product during isolation of MONAP did not stimulate human neutrophil chemotaxis.

511 citations


Journal ArticleDOI
TL;DR: Results indicate that FGF has neurotrophic activity in the adult central nervous system, and that this molecule is able to rescue adult retinal ganglion cells from axotomy induced cell death.

355 citations


Journal ArticleDOI
TL;DR: In this paper, it was shown that monopole condensation is responsible for confinement in U(1) lattice gauge theory and that this mechanism persists in SU(2) nonabelian gauge theories.

313 citations


Journal ArticleDOI
TL;DR: In this paper, the abelian projection of SU(n) gauge theories is carried out both in the continuum and on the lattice, and the degrees of freedom are abelians, gluons, quarks, and magnetic monopoles.

283 citations


Journal ArticleDOI
TL;DR: The responses of these organs to electrical stimulation of visceral nerves, and their reflex responses to electrical and natural stimulation of afferent fibers, lead to the general conclusion that several distinct classes of pre- and postganglionic neurons exist.
Abstract: The lumbar sympathetic outflow projects through the lumbar splanchnic, lumbar colonic, and hypogastric nerves (and to a lesser degree through the sacral sympathetic chain and pelvic nerves). It is thought to be involved in the regulation of the storage and evacuation functions of the following three organ systems: lower urinary tract, hindgut, and reproductive organs. In addition, it controls vascular resistance and capacitance. Thus the target tissues of the postganglionic neurons are vascular smooth muscle, visceral smooth muscles, probably secretory epithelia, and also neurons in the enteric nervous system and the pelvic ganglia. The preganglionic neurons are situated in the caudal part of the spinal representation, neurons associated with the colon being located rostral to those associated with the pelvic organs. Most lie medial to the classical intermediolateral cell column that may contain mainly vasoconstrictor neurons. Most (if not all) preganglionic neurons are cholinergic; some also contain an identified peptide. Most of the postganglionic neurons are situated in the inferior mesenteric ganglion (or equivalent structures); again, those projecting to the colon lie rostral to those projecting to the pelvic organs. Others lie in intercalated prevertebral ganglia, in the pelvic plexus, and in sacral paravertebral ganglia. The majority is noradrenergic, and most also contain one or several peptides, the topographical distribution of which appears to characterize functional subgroups of neurons. The terminations of noradrenergic axons in many pelvic organs probably make close contact with both vascular and nonvascular effectors. In the colon, most endings are located in the enteric plexuses. The responses of these organs to electrical stimulation of visceral nerves, and their reflex responses (together with those observed in the efferent axons of visceral nerve trunks) to electrical and natural stimulation of afferent fibers, lead to the general conclusion that several distinct classes of pre- and postganglionic neurons exist. 1) Vasoconstrictor neurons demonstrate ongoing activity with cardiac rhythm and appropriate reflexes to stimulation of cardiovascular afferent receptors and respond only weakly to natural stimulation of visceral receptors. 2) MR neurons respond to visceral stimuli but are not influenced from arterial baro- and chemoreceptors. These show at least two different response patterns consistent with their separate involvement in the reciprocal behavior of the colon and bladder. 3) Other neurons are silent in anesthetized animals and do not respond to any stimuli used thus far.(ABSTRACT TRUNCATED AT 400 WORDS)

246 citations


Journal ArticleDOI
Carmen Albajar1, Michael Albrow2, O. C. Allkofer3, G.T.J. Arnison2  +198 moreInstitutions (15)
TL;DR: In this paper, a search for B0↔B¯0 oscillations (mixing) using events with two identified muons from data collected at the CERN p¯p collider is reported.

165 citations


Journal ArticleDOI
TL;DR: The high microbial incorporation of leucine and thymidine during winter demonstrated that the nutrient supply rather than temperature is the dominating factor determining microbial production.
Abstract: Seasonal and spatial distributions of extracellular enzymatic activities and microbial incorporations of dissolved organic substrates were followed in sediments of the brackish water Kiel Bight (Baltic Sea, Federal Republic of Germany). Enzymatic hydrolysis of polymeric organic compounds was determined by means of fluorogenic substrates (4-methylumbelliferyl-β-d-glucoside, l-leucine-4-methylcoumarinyl-7-amide hydrochloride); incorporation of dissolved organic substrates into microbial biomass was measured by using tritiated substances (acetate, leucine, and thymidine). Based on a recently developed core injection technique, substrates were injected in microliter portions into undisturbed sediment cores. Enzymatic and incorporation activities underwent strong seasonal variations related to the enrichment of organic material in the sediment surface following sedimentation events. The input of the phytoplankton bloom during autumn caused stimulation of both enzymatic hydrolysis of polymeric organic compounds and microbial incorporation of dissolved organic substrates. Following input by spring phytoplankton bloom, mainly incorporation activities were stimulated. In late spring the development of the benthic fauna obviously greatly influenced microbial activities. During summer individual periods of high microbial activities were observed which might be traced back to short-term sedimentation events. The high microbial incorporation of leucine and thymidine during winter demonstrated that the nutrient supply rather than temperature is the dominating factor determining microbial production. Stimulation of microbial activities arose from the sediment surface and spread out relatively quickly into deeper horizons. Generally, the sediments were characterized by distinct patterns of interrelationships between the individual parameters of microbial activities measured.

164 citations


Journal ArticleDOI
TL;DR: It was found that at pH values at which no significant de-O-acetylation is observed, Neu 5,7Ac2 can easily be transformed into Neu5,9Ac2, and Neu4,5Ac2 does not give rise to O-acety migrations.
Abstract: Highly purified N-acetyl-4-O-acetylneuraminic acid (Neu4,5Ac2), N-acetyl-7-O-acetylneuraminic acid (Neu5,7Ac2) and N-acetyl-7,9-di-O-acetylneuraminic acid (Neu5,7,9Ac3) were used to study spontaneous migrations of acetyl groups between hydroxyl groups. The techniques applied involved thin-layer chromatography, gas-liquid chromatography/mass spectrometry, high-performance liquid chromatography and 360-MHz 1H-NMR spectroscopy. It was found that at pH values at which no significant de-O-acetylation is observed: (a) Neu5,7Ac2 can easily be transformed into Neu5,9Ac2, (b) Neu5,7,9Ac3 yields an equilibrium of Neu5,7,9Ac3 and Neu5,8,9Ac3 in a molar ratio of approximately 1:1, and (c) Neu4,5Ac2 does not give rise to O-acetyl migrations. The importance of these findings is discussed in terms of the biosynthesis of O-acetylated sialic acids.

143 citations


Journal ArticleDOI
K. Schätzel1
TL;DR: In this article, the authors use a photon detection process to measure the Doppler shifts of the scattered light in a laser beam, and then use the photon structure functions to resolve very small particle displacements.
Abstract: The motion of small scatterers in a laser beam results in Doppler shifts of the scattered light. Various homodyne or heterodyne experiments may be used to measure such shifts. The stochastic nature of spatial particle arrangements and of the photon-detection process leads to statistic data processing schemes like temporal correlation or the computation of structure functions. Photon correlation is one of these schemes and has found numerous applications in velocimetry and Brownian motion studies. Topics of current interest are dead-time corrections, the use of photon structure functions, and multiple tau measurements, which access large ranges of time constants in a single run. More recent data processing techniques are recurrence rate correlation for the immediate determination of velocity correlation functions in seeded fluid flows and the measurement of amplitude-weighted phase structure functions, which is able to resolve very small particle displacements otherwise completely obscured by random Brownian motion. Rate correlation found applications in hydrodynamic studies of the route to turbulence, while the major use of phase structure function processing is a very significant increase in the sensitivity of electrophoretic mobility measurements by light scattering.

134 citations


Journal ArticleDOI
TL;DR: The discharge characteristics of sacral visceral afferents supplying the urinary bladder, urethra, colon and anus to mechanical stimuli were analyzed in the anaesthetized cat and it was concluded that the pelvic afferent units from the bladder, Urethra and colon consist of distinct populations with characteristic response patterns.
Abstract: The discharge characteristics of sacral visceral afferents supplying the urinary bladder, urethra, colon and anus to mechanical stimuli were analyzed in the anaesthetized cat. The stimuli used were passive distension (urinary bladder, colon), isovolumetric contraction (urinary bladder), movements of the urethral catheter and mechanical shearing stimuli (mucosal skin of the anal canal). (1) In total 245 afferent units which projected in the pelvic nerve were isolated from the sacral dorsal roots. From one of the following organs, urinary bladder, colon, urethra and anus 117 afferent units were activated. By these stimuli from the bladder, urethra and anus 122 afferent units could not be activated, and as far as tested also not from the colon; in 6 afferent units the classification was unclear. (2) Afferent units from the urinary bladder and the colon responded consistently to passive distension of the respective organ. The units from the urinary bladder showed graded responses at intraluminal pressures of about 10–70 mm Hg and responded also to isovolumetric contractions of the organ. The thresholds of the units from the bladder to passive distension and contraction varied from about 5 to 20 mm Hg intravesical pressure. (3) The afferent units from the urethra and the anus did not react or showed some weak phasic and irregular responses to distension and contraction applied to the urinary bladder or to distension of the colon. They were consistently excited by low threshold mechanical stimulation of the urethra and anus, respectively. (4) The axons from the bladder, urethra and anus were presumably myelinated (conduction velocity above 2 m/s) and conducted at 10.3±6.1 m/s (n=34, mean±SD), 26.3±9.3 m/s (n=13) and 9.5±5.1 m/s (n=37), respectively. The axons from the colon conducted at about 0.5 to 16 m/s (n=20), 13 of them conducting at less than 2 m/s. About 75% of the axons which could not be activated by mechanical stimulation of the visceral organs were presumably unmyelinated (conduction velocity below 2 m/s). (5) Some ongoing activity was found in 9 out of 26 afferent units from the anus but, with one exception, the afferent units from the bladder, urethra and colon were silent. (6) It is concluded that the pelvic afferent units from the urinary bladder, urethra, colon and anus consist of distinct populations with characteristic response patterns. There is no indication from this investigation that the urinary bladder is supplied by sacral afferents which are only recruited at high intravesical pressures during passive distension and isovolumetric contractions and which are possibly associated with pain.

134 citations


Journal ArticleDOI
TL;DR: Increased sensitization against foreign protein together with high susceptibility to cutaneous infection present in AD is in contrast to high phagocyte responsiveness in psoriasis, where concurrent infections are rare.
Abstract: In this report we investigate the simultaneous occurrence of psoriasis and atopic dermatitis (AD) as well as the association with infectious skin diseases. Among 29,159 patients hospitalized between 1953 and 1983, 8.5% (2,467 patients) were treated for psoriasis, while 1.6% (470 patients) were hospitalized for AD treatment. On the basis of incidence rates for both diseases, 36 patients (0.14%) with both psoriasis and AD were expected to be seen. However, the two conditions were simultaneously present in 2 patients only. Approximately 30% of the AD patients were suffering from either bacterial or viral infection, while this complication occurred in 6.7% of psoriatics. In addition, among 48 patients hospitalized for eczema herpeticatum 39 were atopics and none was psoriatic. The data demonstrate that the occurrence of psoriasis and AD in one and the same patient is quite rare and this may be related to conflicting immune defense patterns. Thus, increased sensitization against foreign protein together with high susceptibility to cutaneous infection present in AD is in contrast to high phagocyte responsiveness in psoriasis, where concurrent infections are rare.

Journal ArticleDOI
27 Feb 1987-Sarsia
TL;DR: Culture experiments with whole animals showed that the pogonophores can be kept longer than two weeks only in the presence of methane, and rod-shaped bacteria with intracytoplasmic membrane stacks hitherto not observed in other endosymbiotic bacteria were revealed.
Abstract: Siboglinum poseidoni FLUGEL & LANGHOF, a recently described pogonophore from the central Skagerrak, is equipped with a strand of bacteria-containing tissue. Electron microscopy revealed rod-shaped bacteria with intracytoplasmic membrane stacks hitherto not observed in other endosymbiotic bacteria. Bacteria from the pogonophoran tissue and the sediment were cultured in mineral media designed for chemoautotrophic and methylotropic bacteria. The dominant bacteria in the methane enrichment cultures showed identical membrane stacks. The uptake and oxidation of methane by the animals was proved by incubation experiments with 14CH4. 14C was incorporated by both the homogenized trunk tissue and whole animals within their tubes. The 14CH4-fixation into high molecular cell compounds was demonstrated by autoradiography. Culture experiments with whole animals showed that the pogonophores can be kept longer than two weeks only in the presence of methane (air: methane 4: 1).

Journal ArticleDOI
TL;DR: The fact that the patient demonstrated no natural killer-cell or activated killer- cell activity against the Se-Ax cell line may in part explain the successful establishment of the continuous cell line from bulk culture.
Abstract: A continuous cell line, Se-Ax, from a patient with Sezary syndrome has been established. The Se-Ax cell line is IL-2 dependent, requires human serum for permanent growth, and has the following phenotype: CD1-, CD2+, CD3+, CD4-, CD5-, CD8-, CD20-, CD25+; it expresses the T9, T10, and HLA-DR antigens. This cell line reveals multiple chromosome aberrations as seen in the most abundant abnormal clone in peripheral blood. Therefore, it is not unlikely that it derives from tumor cells. A putative cytotoxic cell line derived from the same patient has only weak killer-cell activity against the autologous permanent cell line: this CD8+ cytotoxic cell line has a 14q+ chromosomal marker. The fact that the patient demonstrated no natural killer-cell or activated killer-cell activity against the Se-Ax cell line may in part explain the successful establishment of the continuous cell line from bulk culture.

Journal ArticleDOI
TL;DR: The results suggest that immunocytochemical staining with the Ki-67 may be a useful method for measuring the growth fraction in brain neoplasms.
Abstract: The monoclonal antibody Ki-67, which reacts with cells in the active part of the cell cycle, was used to evaluate immunocytochemically the growth fraction in 22 primary brain neoplasms. The percentage of labelled cells reflected the histological grade of malignancy of each neoplasms. High percentage of Ki-67-positive cells were observed in one choroid plexus carcinoma (60%), one primary melanoma of meninges (40%), three medulloblastomas (40%–50%), one anaplastic astrocytoma and six glioblastomas (10%–40%). One ependymoma had 7% positive cells. Rare positive cells (1%) were present in one pilocytic astrocytoma and one ganglioglioma. Except one negative case, the meningiomas (five cases) had values of positivity ranging from 1% to 6%. Two acoustic schwannomas were negative. These results suggest that immunocytochemical staining with the Ki-67 may be a useful method for measuring the growth fraction in brain neoplasms.

Journal ArticleDOI
Carmen Albajar1, Michael Albrow2, O. C. Allkofer3, G.T.J. Arnison2  +198 moreInstitutions (15)
TL;DR: In this article, the authors report evidence for beauty particle production through the observation of dimuon events from proton-antiproton collisions at energies of √ s=546 GeV and √s=630 GeV at the CERN collider.

Journal ArticleDOI
TL;DR: In this paper, the proximal stump of a transected hindlimb cutaneous nerve was sutured to the distal stump of the tibial nerve.

Journal ArticleDOI
TL;DR: Only the families mentioned in the following phylogenetic system of the Mecoptera are definitely members of the order.
Abstract: . Many families like the Mesochoristidae, Agetopanorpidae and Permopanorpidae, which were believed by earlier writers to be Mecoptera, are members of the stem group of the Antliophora (Diptera Mecoptera+Siphonaptera) or of stem groups of monophyletic groups of even higher rank (e.g. Mecopteroidea). Others - like the so-called ‘Pro-tomecoptera’ from the Permian of the Kusnetsk Basin - are not even closely related to the Mecopteroidea. Only the families mentioned in the following phylogenetic system of the Mecoptera are definitely members of the order: 1 Nannomecoptera (Nannochoristidae) 2 Pistillifera 2.1 Raptipedia (Neorthophlebiidae, Bittacidae, Cimbrophlebiidae) 2.2 Opisthogonopora 2.2.1 Boreomorpha (Boreidae) 2.2.2 Meropomorpha (Meropeidae) 2.2.3 Panorpomorpha 2.2.3.1 Eomeropina (Eomeropidae=Notiothaumidae) 2.2.3.2 Panorpina 2.2.3.2.1 Apteropanorpini (Apteropanorpidae) 2.2.3.2.2 Panorpini 2.2.3.2.2.1 Choristoidea (Choristidae) 2.2.3.2.2.2 Panorpoidea (Orthophlebiidae, Dinopanorpidae, Austropan-orpidae, Muchoriidae, Panorpodidae, Panorpidae) The Orthophlebiidae and Neorthophlebiidae are not monophyletic. There are, however, no characters preserved which would allow a clarification of the exact relations between members of these two groups and the families derived from them. The fossil Xenochoristidae, Triasso-choristidae, Mesopanorpodidae and Robinjohniidae may be further members of the Mecoptera. Their exact phylogenetic relations, however, are unknown.

Journal ArticleDOI
TL;DR: In this article, quasi-homogeneous layers in vertical profiles of temperature and salinity in the eastern North Atlantic near Madeira indicate the existence of a subtropical Mode Water in the Eastern Basin.
Abstract: Quasi-homogeneous layers in vertical profiles of temperature and salinity in the eastern North Atlantic near Madeira indicate the existence of a subtropical Mode Water in the Eastern Basin. Temperature sections show a maximum horizontal extent of at least 500 km. The frequency distribution analysis of homogeneous layers in a historical XBT dataset shows a Mode Water formation region near and to the north of Madeira. This Mode Water is found at increasing depths and displaced to the west and southwest during the course of the year after its formation by wintertime convection. It disappears almost completely, due to mixing, before the next winter. Volume estimates suggest that this Madeira Mode Water in the eastern Atlantic accounts for 15–20% of the total Central Water formation in the corresponding density range as obtained from tracer studies in the North Atlantic gyre.

Journal ArticleDOI
TL;DR: A new mesophilic, monotrichously flagellated methane-producing coccus of ≦1μm in diameter was isolated from an anaerobic sour whey digester, originally inoculated with sewage sludge.
Abstract: A new mesophilic, monotrichously flagellated methane-producing coccus of ≦1μm in diameter was isolated from an anaerobic sour whey digester, originally inoculated with sewage sludge. Growth and methane production were observed with H2/CO2, formate and — less effectively — with 2-propanol/CO2. The isolate grew at temperatures between 15° C and 45° C with the optimum at around 37° C. Acetate, yeast extract and tungstate were required in the medium. Clarified rumen fluid stimulated growth.

Journal ArticleDOI
TL;DR: The existence of energetic anticyclonic mid-depth vortices of Mediterranean Water (meddies) questions the validity of a conventional advective-diffusive balance in the eastern Atlantic subtropical gyre as discussed by the authors.
Abstract: The existence of energetic anticyclonic mid-depth vortices of Mediterranean Water (meddies) questions the validity of a conventional advective–diffusive balance in the eastern Atlantic subtropical gyre. A mesoscale experiment in the Azores–Madeira region reveals a link of these meddies to large-scale subsurface meanders. For the first time it is shown that meddies may have strong surface vorticity, indicative of a generation process involving the Azores Current—a deep reaching near-surface jet.

Journal ArticleDOI
TL;DR: It is demonstrated that, in additon to endosperm-specific hordothionin mRNA, a closely related but distinct second group of thionin mRNAs is present in the barley leaf during early seedling development.
Abstract: In etiolated barley seedlings a highly abundant mRNA encoding a 15 000 Mr polypeptide is present whose concentration rapidly declines upon illumination. The amino acid sequence of the 15 000 Mr polypeptide has been deduced from cDNA sequences and the polypeptide has been identified as a high-molecular-weight thionin precursor. Closely related thionins, most of them highly toxic, have been described previously in several higher plants. In cereals the occurrence of these thionins has been thought to be confined to the seeds. Our present data demonstrate that, in additon to endosperm-specific hordothionin mRNA, a closely related but distinct second group of thionin mRNAs is present in the barley leaf during early seedling development. Since the appearance of the bordothionin mRNA is not controlled by light, two different gene families for thionins exist whose expression seems to be under a different mode of developmental control.

Journal ArticleDOI
TL;DR: The phylogenetic incoherency of the genus Bacillus as presently described is demonstrated by analysis of both published and new data from comparative 16S rRNA cataloguing of nine Bacillus species and a number of related non-Bacillus taxa, i.e. Caryophanon latum, Filibacter limicola and Planococcus citreus.
Abstract: SUMMARY: The phylogenetic incoherency of the genus Bacillus as presently described is demonstrated by analysis of both published and new data from comparative 16S rRNA cataloguing of nine Bacillus species and a number of related non-Bacillus taxa, i.e. Caryophanon latum, Filibacter limicola and Planococcus citreus. While the ellipsoidal-spore-forming bacilli, e.g. B. subtilis and allied species, formed a coherent cluster, the round-spore-forming bacilli showed a higher degree of relationship to the non-spore-forming organisms than these bacilli show among each other. Thus B. sphaericus clustered with C. latum, B. globisporus grouped with F. limicola, B. pasteurii with Sporosarcina ureae, and ‘B. aminovorans’ with P. citreus, respectively. These organisms formed two related subclusters which, in their phylogenetic depth, are comparable to that of the B. subtilis subline. With the exception of ‘B. aminovorans’ the 16S rRNA phylogeny was entirely consistent with the distribution of murein types. Even more distantly related to and grouping outside the main Bacillus cluster was B. stearothermophilus, which displayed a moderate relationship to Thermoactinomyces vulgaris. Taxonomic problems arising from the new insights into the intrageneric relationships of Bacillus are discussed.

Journal ArticleDOI
TL;DR: Rifampin preferentially affects norantipyrine or desmethyl‐ and 3‐hydroxydiazepam metabolic formation, suggesting induction of different (iso)zymes of cytochrome P‐450.
Abstract: The elimination of diazepam and antipyrine and the urinary excretion of their metabolites were investigated in 21 healthy volunteers before and after 7 days of administration of antipyrine, 1200 mg, and rifampin, 600 or 1200 mg. After administration of antipyrine and rifampin in two doses, antipyrine total body clearance increased by 53% and 60% or 98%, respectively. The clearance to metabolite showed a preferential induction of the norantipyrine pathway with different proportions after antipyrine and rifampin; rifampin, 1200 mg, also enhanced the 4-hydroxyantipyrine pathway further. After antipyrine, diazepam total body clearance was increased by 102%, affecting all metabolic pathways to a similar extent. After rifampin in both doses, diazepam total body clearance rose equally to 300% and desmethyl- and 3-hydroxydiazepam metabolic clearance to 400%. Therefore rifampin preferentially affects norantipyrine or desmethyl- and 3-hydroxydiazepam metabolic formation, suggesting induction of different (iso)zymes of cytochrome P-450.

Journal ArticleDOI
Carmen Albajar1, Michael Albrow2, O. C. Allkofer3, A. Astbury4  +194 moreInstitutions (15)
TL;DR: In this paper, the photino is assumed to be the lightest supersymmetric particle and that it is massless, and the authors find a limit on the squark mass of m q >45 GeV /c 2 at 90% CL.

Journal ArticleDOI
TL;DR: In this paper, the authors measured the absorption of phytoplankton from cultures and natural samples on filters with various optical setups including collimated and diffuse irradiation and measurements of wetted filters within an integrating sphere.
Abstract: Spectra1 absorption of phytoplankton from cultures and natural samples was measured on filters with various optical setups including collimated and diffuse irradiation and measurements ofwetted filters within an integrating sphere. In suspensions within an integrating sphere, specific absorption coefficients for laboratory cultures varied by a factor of only two. Measurements on filters yielded values dependent on filter load. Specific absorption coefficients derived from measurements of sample filters were considerably higher than values obtained from suspensions in an integrating sphere due to increased diffuseness of irradiance and to pathlength amplification by filter-particle and particle-particle interactions. Measured absorption of phytoplankton in the blue can be increased greatly by absorption of detritus, evident from absorption spectra of depigmented samples on filter. After subtracting detrital absorption, absorption spectra of phytoplankton are qualitatively similar to the corresponding quantum-corrected fluorescence excitation spectra. The detritus-corrected ratio of absorption at 440 vs. 675 nm shows average values between 1 and 1.5. Comparison with published values shows that specific in vivo absorption coefficients of phytoplankton arc mostly overestimated as a result of the methodology applied. In the blue region of the spectrum, overestimation of phytoplankton absorption in field samples is possible if detrital absorption is neglected.

Journal ArticleDOI
01 Jan 1987
TL;DR: In this article, a structural model for the incommensurate phase is based on the misfit between the tetrahedral (Mg, Fe2+)Si2O 7 sheets and the Ca2+ ions.
Abstract: Synthetic melilites on the join Ca2MgSi2O7 (akermanite) — Ca2FeSi2O7 (iron akermanite) with Fe/(Fe+Mg) from 0.0 to 0.7 exhibit, at room temperature, an incommensurate phase with a rectangular modulation of a wavelength of about 19 A in the [110] direction. Upon increase of temperature, they transform to a commensurate melilite structure at about 80° C for Fe/(Fe+Mg)=0.0 and about 250° C for Fe/(Fe+Mg)=0.6. In addition to the T(2) positions of the melilite structure filled by Si, the incommensurate phase exhibits two distinguishable T(1) sites containing the Mg and Fe2+. These two sites merge into one site during the phase transition from the incommensurate to the commensurate phase. A structural model for the incommensurate phase is based on the misfit between the tetrahedral (Mg, Fe2+)Si2O 7 4− sheets and the Ca2+ ions.

Journal ArticleDOI
TL;DR: The results substantiate the view that Hodgkin's lymphomas contain clonal lymphocyte populations and that different rearrangement patterns may be associated with different subclasses of HD.
Abstract: Twenty-two cases of Hodgkin's disease (HD), representing the 4 different subclasses, were studied by immunophenotypic and immunogenotypic analysis. Quantitative immunophenotypic analysis of HD infiltrates showed a predominance of CD3-positive T cells in all subtypes except the lymphocytic depletion (HDLD) subtype. Only 5 samples of HD [2 of lymphocytic predominance (HDLP), 2 of mixed cellularity (HDMC), and one of nodular sclerosis type (HDNS)] were found to have both their Ig and T-cell antigen receptor (TcR) genes in the germ-line configuration. The remaining patients with HDLP (3 cases), HDNS (5 cases), and HDMC (4 cases), all exhibited rearrangements of either TcR gamma or TCR gamma and TcR beta genes, while all 5 cases of HDLD had either TCR gamma or immunoglobulin heavy-chain gene rearrangement. These results substantiate the view that Hodgkin's lymphomas contain clonal lymphocyte populations and that different rearrangement patterns may be associated with different subclasses of HD.

Journal ArticleDOI
TL;DR: The promoter region and the gene coding for the S1 subunit of pertussis toxin from additional B. parapertussis and B. bronchiseptica strains are cloned and sequenced to elucidate further the evolutionary relationships between the Bordetella species.
Abstract: Summary The nucleotide sequence of the pertussis toxin operon of Bordetella pertussis, Bordetella parapertussis and Bordetella bronchiseptica, has shown that the last two species contain many common mutations and are likely to derive from a common ancestor (Arico and Rappuoli, 1987). To elucidate further the evolutionary relationships between the Bordetella species, we have cloned and sequenced the promoter region and the gene coding for the S1 subunit of pertussis toxin from additional B. pertussis strains, such as the type strain BP 18323 and two recent clinical isolates, namely strain BP 13456 from Sweden and strain BP SA1 from Italy. While the strains BP SA1 and BP 13456 are shown to differ from the published B. pertussis sequences by only one base pair, the type strain BP 18323 contains a total of 11 base-pair substitutions. Remarkably, 9 of the 11 substitutions found in BP 18323 are also common to B. parapertussis and B. bronchiseptica, strongly suggesting that this strain derives from the same ancestor as B. parapertussis and B. bronchiseptica. Computer analysis of the sequence data allows the construction of an evolutionary ‘tree’ showing that the B. pertussis strains are very homogeneous and significantly distant from B. parapertussis and B. bronchiseptica. Therefore the proposed conversion from B. parapertussis to B. pertussis appears highly improbable.

Journal ArticleDOI
Bernd Marler1
01 Sep 1987-Zeolites
TL;DR: Using hydrothermal techniques the aluminium-free end member of ZSM-22 (silica-ZSM- 22) has been synthesized in the presence of any one of the amines (e.g., ethylenediamine, diethylamine, triethylenetetramine or 1aminobutane) as discussed by the authors.

Journal ArticleDOI
TL;DR: Six liver carboxylesterases previously isolated from rat liver microsomes were compared with genetically defined liver esterases of various reference strains using polyacrylamide gel electrophoresis and isoelectric focusing to identify alloenzymic forms of ES-3, ES4, ES-8/ES-10 and ES-15 according to the genetic nomenclature recommended by van Zutphen.