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We used the Hedley sequential fractionation scheme to assess phosphorus (P) chemistry of a strongly weathered soil from a humid lowland forest in Panama. Our analyses were part of a factorial experiment of nitrogen, P, and potassium addition, with nutrients added annually, i.e. a chronic input. The aim was to examine changes in soil P chemistry with 7 years of nutrient addition for soils collected in the wet season and the dry season. The majority of P occurred in fractions extracted by NaOH (24% of the total soil P) and hot concentrated HCl (58% of the total). Organic P (Po) was ~54% of extractable P. Labile P, defined as Po plus inorganic P (Pi) extracted by NaHCO3, was largely Po (84% of the NaHCO3-extractable P). Chronic P addition increased NaHCO3-extractable Po several-fold and NaOH-extractable Pi two-fold. Seasonal variation occurred for labile P and NaOH-extractable P, whereas occluded P did not vary throughout the study period. Extractable P was ~15% higher in surface than subsurface soil. We added 350kgPha-1 during the 7-year period and recovered ~55% by sequential extraction. According to biogeochemical theory, added P should show up in fractions with the shortest residence times, e.g. labile P. Our finding that added P accumulated in fractions with presumably long residence times, i.e. extracted by NaOH (bound) and hot concentrated HCl (occluded), suggests that greater attention be paid to the short-term dynamics of bound and occluded P in strongly weathered tropical forest soils.

We evaluated spatial heterogeneity for pH and a comprehensive set of nutrient and trace elements in surface (0–0.1m depth) and subsurface (0.3–0.4m depth) soils across 26.6ha of old-growth, lowland, tropical moist forest, established on a highly weathered soil in Panama. Little is known about spatial heterogeneity patterns of soil properties in tropical forest soils. Soil was moderately acidic (pH 5.28) with low concentrations of exchangeable base cations (13.4cmolc/kg), Bray-extractable PO4(2.2mg/kg), KCl-extractable NO3(5.0mg/kg), and KCl-extractable NH4(15.5mg/kg). The coefficient of variation for soil properties ranged from 24% to >200%, with a median value of 84%. Geostatistical analysis revealed spatial dependence at a scale of 10–100m for most of the soil properties; however, pH, NH4, Al, and B had spatial dependence at a scale up to 350m. Best-fit models to individual variograms included random, exponential, spherical, Gaussian, linear, and power functions, indicating many different spatial patterns among the set of soil properties. Correlation among individual elements was poor, indicating independent patterns. Our results show complex spatial patterns in soil chemical properties and provide a basis for future investigations on soil–plant relationships and soil nutrient niche differentiation.

The trinuclear complexes {(Me2P-η⁶-C6H5)2M}2Ni 7^•• (M = V), 8 (M = Cr), {(Me2P-η⁶-C6H5)2M}2CoH 10^•• (M = V), 11 (M = Cr), and {(Me2P-η⁶-C6H5)(η⁶-C6H6)M}2Ni(CO)2 14^•• (M = V) and 15 (M = Cr) have been prepared and characterized by means of X-ray crystal structure analysis in two representative cases (11, 15). The “closed” complexes 7^••, 8, 10^••, and 11 are semirigid, and the “open” species 14 and 15 are conformationally flexible. Magnetocommunication has been studied for the diradicals 7^••, 10^••, 14^••, and 15^•+•+ by fluid solution EPR spectroscopy. Comparison of 7^•• with 10^•• shows that the magnetic moment of the nucleus ⁵⁹Co fails to shape the ⁵¹V hyperfine structure in any discernible way. The flexibility of 14^•• furnishes this complex with the largest exchange coupling constant J in the series and is responsible for a pronounced temperature dependence, as demonstrated by alternating EPR line widths upon lowering the temperature. Isoelectronic replacement of V^• by Cr^•+ in the terminal sandwich units yielding 15^•+•+ profoundly attenuates the exchange coupling. Cyclic voltammetry reveals that the complex 10^•• engages in a five-step redox chain 2−|−|0|+|2+|3+. Since the central couple 0|+ represents the oxidation of the spiro cobalt atom, the redox splitting δE1/2(0|−,−|2−) is governed by a neutral spacer and δE1/2(3+|2+,2+|+) by a cationic spacer. The positive charge on the spacer exerts a leveling effect in that δE1/2(reduction) = δE1/2(oxidation), contrary to spacers of constant charge, for which δE1/2(reduction) > δE1/2(oxidation) is commonly observed.

An efficient one-pot sequence comprising a homolytic aromatic substitution followed by an ionic Horner−Wadsworth−Emmons olefination for the preparation of a small library of α,β-unsaturated oxindoles is presented. Microwave-induced heating is used to conduct these reactions. The homolytic aromatic substitution is mediated by the persistent radical effect.

The paramagnetic boronic acid (η⁷-C7H7)V[η⁵-C5H4B(OH)2] (3^•) has been prepared and characterized structurally, emphasis being placed on hydrogen bonding motives present in the crystal. EPR spectroscopy reveals that association of 3^• is absent in fluid solution. Tri([5]trovacenyl)boroxine, 4^•••, the cyclic anhydride of 3^•, engages in antiferromagnetic exchange; magnetic susceptometry provides the value J(4^•••) = −1.04 cm^-1. Accordingly, the EPR spectrum of 4^••• in fluid solution points to 22 ⁵¹V hyperfine components separated by one-third of the coupling constant of mononuclear trovacene derivatives. Redox splittings δE1/2 between consecutive oxidation steps of 4^••• are not resolved, i.e., δE1/2 ≤ 60 mV.

A macrocyclic gallium carboxylate (3) is formed on reaction of the digallane(4) R2Ga−GaR2 [R = CH(SiMe3)2], 1, with naphthalene-2,6-dicarboxylic acid, HOOC−C10H6−COOH. The macrocycle comprises 44 atoms, and four Ga−Ga single bonds are connected by four dicarboxylato bridges. The cavity of the heterocycle may be described as a rigid molecular square possessing a largest diameter of 1.86 nm. It encloses four 1,2-difluorobenzene molecules.

The synthesis of three new sterically hindered Hawker−Braslau type alkoxyamines for the nitroxide-mediated living radical polymerization is described. Efficient polymerizations can be performed at 105 °C. With alkoxyamine 11 controlled polymerization of n-butyl acrylate and styrene is possible even at 90 °C. AA and AB diblock copolymers can be prepared in a controlled manner using alkoxyamine 11. Kinetic EPR experiments for the determination of the C−O bond activation energies of the new alkoxyamines are described. Furthermore, ¹H NMR alkoxyamine decomposition studies are presented. These kinetic experiments are used for the discussion of the polymerization results. Furthermore, the X-ray structure of a Hawker-Braslau type nitroxide is presented. X-ray data and ESR data are used to explain the high stability of these nitroxides.

Thermal rearrangement of dicycloheptatriene C14H14 and subsequent reaction with (η⁵-cyclopentadienyl)(tetracarbonyl)vanadium affords [7−7]bitrovacene, μ-η⁷:η⁷-C14H12[(η⁵-C5H5)V]2 (8^••). Sterically induced avoidance of a planar μ-η⁷:η⁷-heptafulvalenediyl bridge leads to a complicated packing pattern of varyingly twisted units of 8^•• which generates a huge unit cell (Z = 72), in stark contrast to the isomer 7^••, for which Z = 2 applies. The isomers 8^•• and 7^•• also differ with regard to the extent of intervanadium electro- and magnetocommunication. Redox splittings δE1/2 of consecutive ET steps are considerably larger for 8^••, compared to 7^••, thereby reflecting the higher contribution the larger ring makes to the SOMO. The higher spin density at the C7 compared to the C5 carbon atoms, which governs the EPR spectra, effects a pronounced gradation of the exchange coupling parameter determined by magnetic susceptometry:  J(7^••) = −2.8, J(8^••) = −24.1 cm^-1.

Die Kristallstrukturen der Titelverbindungen werden mit Hilfe von Röntgen‐Einkristall‐Strukturanalysen ermittelt. NH4[SbCl6] und NH4[WCl6] kristallisieren isotyp miteinander in der Raumgruppe C2/c mit vier Formeleinheiten pro Elementarzelle. Die NH4+‐Ionen liegen auf einer zweizähligen Drehachse, die Metallatome der [MCl6]—‐Ionen besetzen ein Inversionszentrum. Es bestehen schwache interionische Wasserstoffbrückenbindungen.

Syntheses of a series of the title compounds, viz., N(CH2CH2NR)3M−X (1, M = Si, X = Me, R = SiMe3; 2, M = Si, X = Et, R = SiMe3; 3, M = Si, X = n-Bu, R = SiMe3; 4, M = Si, X = vinyl, R = SiMe3; 5, M = Si, X = Ph, R = SiMe3; 6, M = Ge, X = Me, R = SiMe3; 7, M = Ge, X = n-Bu, R = SiMe3; 8, M = Ge, X = Ph, R = SiMe3; 9, M = Sn, X = n-Bu, R = SiMe3; 10, M = Sn, X = Ph, R = SiMe3; 11, M = Si, X = vinyl, R = Me; 12, M = Ge, X = Me, R = Me) by the reaction of X−MCl3 with N(CH2CH2NSiMe3Li)3 or with N(CH2CH2NMeLi)3 are reported. Reactions of the novel compounds X−Ge(NMe2)3 (15, X = Ph; 16, X = 1-naphthyl; 17, X = 9-antracenyl; 18, X = 9-phenantrenyl) with N(CH2CH2NHMe)3 or N(CH2CH2NH2)3 resulted in new 1-arylazagermatranes, N(CH2CH2NMe)3Ge−X (19, X = Ph; 20, X = 1-naphthyl; 21, X = 9-antracenyl; 22, X = 9-phenantrenyl) and N(CH2CH2NH)3Ge−X (23, X = Ph; 24, X = 1-naphthyl; 25, X = 9-phenantrenyl), respectively. 1-Phenylazagermatrane (23) is transformed to 8 by treatment with n-BuLi/Me3SiCl. Composition and structures of novel compounds were established by elemental analyses, ¹H, ¹³C, and ²⁹Si NMR spectroscopy, and mass spectrometry. The X-ray structural studies of 10 and 19 clearly indicated the presence of a transannular interaction M←Nax for both compounds. quasi-Azametallatranes 5 and 8 possess extremely long M←Nax distances.

The biradicals 1,8-di([5]trovacenyl)naphthalene (6), 1,5-di([5]trovacenyl)naphthalene (7), and 1,3-di([5]trovacenyl)benzene (8) and the monoradical 1-[5]trovacenylnaphthalene (9) have been prepared and studied by means of single-crystal X-ray diffraction (6, 8, 9), cyclic voltammetry, EPR spectroscopy, and magnetic susceptometry. Comparison of the magnetic properties of 6−9 reveals that π-stacking, as encountered in 6, largely enhances exchange interaction between the two singly occupied V(3dz^{2) orbitals. The effect of π-stacking on the electrochemical properties, as manifested in the redox splitting between consecutive electron transfer steps, is less pronounced. Redox splittings δE1/2 for consecutive reductions exceed those for oxidations of binuclear trovacenes, δE1/2(2+/+, +/0) being apparent for π-stacked 6 only. Because of the orthogonality of the metal-centered redox orbitals V1(dz2) and V2(dz2) and the η5-cyclopentadienyl π-orbitals, electro- and magnetocommunication are indirect processes. Electrocommunication rests on changes of the donor/acceptor properties of V1,V2 caused by oxidation or reduction which govern metal−ligand charge distribution; the latter changes are transmitted via the spacer. Magnetocommunication takes the form of antiferromagnetic coupling, which can be traced to spin polarization of filled π-orbitals of the bridge by orthogonal singly occupied vanadium 3dz2 orbitals.}

Die Kristallstrukturen einer Serie von Verbindungen mit Kationen des Typs [R3PNH2]+, [R3PN(H)SiMe3]+und [R3PN(SiMe3)2]+, in denen R für verschiedene organische Reste steht, werden mit Hilfe von Röntgenstrukturanalysen an Einkristallen bestimmt. Die disilylierten Verbindungen [Me3PN(SiMe3)2]+I–, [Et3PN(SiMe3)2]+I–und [Ph3PN(SiMe3)2]+I3–werden mit Me3SiI aus den entsprechenden silylierten Phosphaniminen R3PNSiMe3gewonnen.

By means of metal−ligand vapor co-condensation techniques the homoleptic arsenine sandwich complexes (η⁶-C5H5As)2Ti (2), (η⁶-C5H5As)2V (3), and (η⁶-C5H5As)2Cr (4) have been prepared. 2 is the first example of an unsubstituted group 15 heteroarene sandwich complex which yielded to full structural characterization by X-ray diffraction. The most remarkable feature of the structure of 2 in the crystal is the synperiplanar conformation and the short intramolecular interannular As···As distances which imply secondary bonding. The latter may also contribute to the packing since interannular As···As distances, which fall short of the sum of the van der Waals radii, are detected. The result of a competition experiment, in which benzene and arsenine are offered as ligands to chromium, illustrate the pronounced preference of chromium for arsenine as an η⁶ ligand. The mixed-ligand complexes (η⁶-C5H5As)(η⁶-C6H6)Cr (6) and (η⁶-C5H5As)Cr(CO)3 (8) have also been prepared and studied spectroscopically in order to underpin the notion that arsenine, compared to benzene, is the superior η⁶ ligand. The study is rounded off by an investigation of the redox behavior of 2, 3, 4, and 6 (cyclic voltammetry) and by EPR measurements on 3^• and 4^•+. The latter confirm the pronounced π-acceptor character of η⁶-arsenine. This conclusion is based on the increase of the hyperfine coupling constant a(⁵¹V) upon going from bis(benzene)vanadium to the arsenine counterpart which is thought to reflect V(dz2) orbital contraction in 3^•, caused by a slight increase of positive partial charge on vanadium.

Die Titelverbindungen entstehen aus den wasserfreien Acetaten von Zink und Kupfer(II) mit Trimethylsilyl‐triethylphosphanimin, Me3SiNPEt3, in Gegenwart von Wasser in Dichlormethan als farblose (1), blaugrüne (2) bzw. blaue (3) Einkristalle, die IR‐spektroskopisch und durch Kristallstrukturanalysen charakterisiert werden.

Die Amido‐Silyloxy‐Komplexe [Na(12‐Krone‐4)2] [M{N(SiMe3)2}3(OSiMe3)] mit M = Sm (1 a), Eu (1 b), Yb (1 c) und Lu (1 d) wurden aus den Trisamiden M[N(SiMe3)3]3und NaOSiMe3in n‐Hexan in Gegenwart von 12‐Krone‐4 als gelbe bis orangerote Kristalle erhalten, von denen 1 aund 1 ckristallographisch charakterisiert wurden. Die Komplexe kristallisieren isotyp miteinander in der monoklinen Raumgruppe I2/a mit 8 Formeleinheiten pro Elementarzelle. Die Metallatome der komplexen Anionen sind tetraedrisch von den drei N‐Atomen der N(SiMe3)2–‐Liganden und von dem O‐Atom des OSiMe3–‐Liganden koordiniert. Die Bindungswinkel M–O–Si sind mit 172,4° für 1 aund 179,3° für 1 cpraktisch linear.

Der Ytterbium‐Komplex [Yb2Cp3(NPPh3)3] mit Sesqui‐Verteilung von Cyclopentadienid‐ und Phosphaniminato‐Liganden wird aus YbCp2Cl und LiNPPh3in siedendem Toluol hergestellt und als gelbe, feuchtigkeitsempfindliche Kristalle isoliert, die drei Moleküle Toluol pro Elementarzelle einschließen. [Yb2Cp3(NPPh3)3] · 3 C7H8(1): Raumgruppe Pbca, Z = 8, Gitterkonstanten bei –80 °C: a = 2727,6(2); b = 1977,5(1); c = 2848,9(2) pm; R = 0,0541. Zwei der (NPPh3)–‐Gruppen verknüpfen die Ytterbiumatome zu einem nichtebenen Yb2N2‐Vierring mit einem Faltungswinkel von 17,1° entlang der Yb…Yb‐Verbindungslinie. Die dritte (NPPh3)–‐Gruppe ist terminal gebunden mit einem kurzen Yb–N‐Abstand von 214,2 pm.

Lithiation of trovacene, (η⁷-C7H7)V(η⁵-C5H5), Li/I exchange, and Pd(dppf)Cl2-catalyzed homocoupling affords [5-5]bitrovacene 5^2•. Intermetallic communication manifests itself in typical biradical features of the EPR spectrum and in the resolution of redox splittings of 147 mV for the two subsequent oxidations and 224 mV for the reductions, respectively. 5^2• adopts a trans conformation in the single crystal (X-ray diffraction) as well as in rigid solution (EPR spectroscopy). A magnetic susceptibility study of 5^2• reveals weak antiferromagnetic coupling (J = −2.78 cm^-1) of the two V(d⁵) centers.

An increased echogenicity of the pancreas (“white pancreas”) was sonographically found in 25 children with various pancreatic and systemic diseases. Fifteen patients with cystic fibrosis had a small white pancreas. Five patients with haemosiderosis, two with pancreatitis and one with Shwachman-syndrome presented with a normal-sized or slightly enlarged pancreas. Fatty infiltration and calcifications of the pancreas can also increase its echogenicity.

Durch Umsetzungen von LnBr3mit NaNHPh in THF im Verhältnis 1 : 1 erhält man die dimeren Seltenerdkomplexe [Ln2Br4(μ2‐NHPh)2(thf)5] (Ln = Sm (1), Ln=Gd (2)) mit verbrückenden Anilidoliganden. Mit dem System LnBr3/NaNHPh/(Me2SiO)3gelangt man zu den vierkernigen Verbindungen [Ln4(μ4‐O)(NHPh)3(OSiMe2NPh)6Na5(thf)7] · THF (Ln=Gd (3), Ln = Yb (4)) mit interstitiellem Sauerstoffatom, die über jeder Kante des Tetraeders einen Oxa‐Dimethylsilyl‐N‐Phenylamido‐Liganden und an drei Ecken einen Anilido‐Liganden tragen. Als Nebenprodukt bildet sich bei dieser Umsetzung die Verbindung [Na4(thf)6Yb2(OSiMe2NPhSiMe2O)2(OSiMe2NPh)2(NHPh)2] (5) mit einem O‐ und N‐verbrückten Yb–Na‐Gerüst. Dieser Komplex enthält neben dem aus den Verbindungen 3und 4bekannten Liganden noch zwei verbrückende N‐Phenyl‐bis(dimethylsilanolato)‐Liganden, die über ihre Sauerstoffatome an Yb‐ und Na‐Ionen binden. Ähnlich aufgebaute dimere Lanthanoidkomplexe erhält man aus der Umsetzung von Lanthanoidhalogeniden mit LiNHtBu. Auch hier bilden sich Oxasilylamido‐Liganden, die zwei Seltenerd‐Ionen verbrücken. In dem Verbindungstyp [Li2Ln(OSiMe2NtBu)2(HNtBu)(thf)]2mit Ln = Sm (6), Gd (7) und Yb (8) ist nun ein O‐ und N‐verbrücktes Ln–Li‐Polyeder enthalten.1: Raumgruppe P21/c, Z = 4, a = 1402,2(3) pm, b = 1768,3(4) pm, c = 1618,1(3) pm, β = 95,46(3)°.2: Raumgruppe P21/c, Z = 4, a = 1404,2(3) pm, b = 1772,0(4) pm, c = 1615,9(3) pm, β = 94,74(3)°.3: Raumgruppe P1, Z = 2, a = 1585,6(3) pm, b = 1715,1(3) pm, c = 2232,4(5) pm, α = 83,31(3)°, β = 78,97(3)°, γ = 74,48(3)°.4: Raumgruppe P1, Z = 2, a = 1585,9(3) pm, b = 1723,3(3) pm, c = 2201,4(5) pm, α = 83,43(2)°, β = 78,21(2)°, γ = 74,53(2)°.5: Raumgruppe P1, Z = 2, a = 1140,1(2) pm, b = 1646,8(2) pm, c = 2483,1(3) pm, α = 76,09(1)°, β = 77,34(1)°, γ = 75,25(1)°.6: Raumgruppe P1, Z = 1, a = 1119,5(1) pm, b = 1215,6(1) pm, c = 1255,1(1) pm, α = 69,71(1)°, β = 81,81(1)°, γ = 67,38(1)°.7: Raumgruppe P1, Z = 1, a = 1120,5(2) pm, b = 1216,0(2) pm, c = 1259,3(2) pm, α = 69,66(1)°, β = 81,85(1)°, γ = 67,87(2)°.8: Raumgruppe P1, Z = 1, a = 1094,1(1) pm, b = 1183,9(1) pm, c = 1314,2(1) pm, α = 64,81(1)°, β = 68,86(1)°, γ = 80,75(1)°.

LiNPPh3reagiert mit den Cyclooctatetraenid‐Komplexen [Ln(C8H8)Cl(THF)2]2von Cer und Samarium in THF‐Lösung unter Bildung der Phosphaniminato‐Komplexe [Ln(C8H8)Li3Cl2(NPPh3)2(THF)3], in denen nach Kristallstrukturanalysen Heterocuban‐Strukturen unter Beteiligung des Lanthanoid‐Metallatoms, der drei Li‐Atome sowie der beiden Cl‐ und der beiden N‐Atome der NPPh3–‐Gruppen vorliegen. Die Kristallstruktur von LiNPPh3zeigt hexamere Moleküle mit einem Li6N6‐Polyeder, das peripher durch die Phenylgruppen abgeschirmt ist. Die Struktur des als Nebenprodukt isolierten [Li(THF)4][Sm(C8H8)2] enthält das Samarium‐Atom in sandwichartiger Koordination durch die beiden η8‐C8H82–‐Ringe, wie es auch von den entsprechenden Anionen mit Cer und Neodym bekannt ist.

Die Titelverbindungen werden durch Reaktion der Cyclopentadienidchloride [M(C5H5)2Cl]2mit LiNPPh3in siedendem Toluol hergestellt und durch Kristallstrukturanalysen charakterisiert. Alle drei Verbindungen kristallisieren isotyp miteinander in der orthorhombischen Raumgruppe Pbca mit Z = 8. Zwei der drei Phosphaniminato‐Gruppen verknüpfen über μ2‐N‐Atome die Metallatome zu fast planaren M2N2‐Vierringen. Die dritte NPPh3–‐Gruppe ist terminal gebunden. Die magnetische Suszeptibilität von [Dy2(C5H5)3(NPPh3)3] · 3 C7H8ist im Temperaturbereich von 1,7 K bis 300 K bei Magnetfeldern zwischen 0,01 T und 5 T mit einem SQUID‐Magnetometer bestimmt worden. Rechnungen auf der Grundlage eines kubischen Ligandenfeldmodells führen zu guter Übereinstimmung zwischen gemessenen und theoretischen Suszeptibilitäten mit plausiblen Ligandenfeld‐Parameterwerten. Die Einbeziehung einer isotropen intramolekularen Spin‐Spin‐Austauschkopplung in das Modell führt zu keiner Verbesserung der Anpassung. Im Rahmen des verwendeten Modells ist somit keine nennenswerte Spin‐Spin‐Kopplung innerhalb der dinuklearen Einheiten nachweisbar.

Ten infants with intractable diarrhea, celiac disease and small bowel resection were treated with a special dietetic regimen called “Baustein” principle. The three major food constituents were added to the formula stepwise: first glucose and maltodextrin followed by protein and vegetable oil or MCT oil. The protein source was a newly developed casein hydrolisate also containing minerals, trace elements and vitamins.

All vaginal deliveries of the Department of Obstetrics and Gynecology of the University Basel (N=4081) during the year 74/73 and of the University Tübingen (N=3249) 75/74 were analysed using an IBM-system 370/135 Only alive singletons beyond the 28th week of gestation were analysed. Clinical management was quite different in the two departments; the incidence of vaginal operations (Basel 11.2%, Tübingen 12.6%), however, as well as the distribution of pH-values and Apgar-scores after 1 min were quite similar. Basel: Acidotic risk (i.e. pHUA<7.200) 13.5%, severe acidotic risk (i.e. pHUA<7.100) 1.55%, low Apgar-scores (1–3) 0.7%. Tübingen: 12.3%, 2.11%, 1.6%. 3.5% of all parturients (Basel) had duration of second stage of labour with active maternal pressure support lasting more than 30 min.

Summary Clinical trials using replication-deficient adenovirus as vectors for gene transfer into the airways of cystic fibrosis (CF) patients are in progress. However, little is known about the prevalence of wild-type adenovirus infections in patients with cystic fibrosis and their effect on lung function. To answer these questions, serum IgG and IgM antibody titers against adenovirus type 5 were prospectively measured by an indirect immunofluorescence assay in 199 CF outpatients and in a control group of 45 healthy children and young adults. In addition, we performed pulmonary function tests when the patients were in stable clinical condition. IgM antibodies against adenovirus were present in 104 of the 199 cystic fibrosis patients (52.3%). IgG antibodies against adenovirus were detected in 192 of the 199 cystic fibrosis patients (96.5%), and were significantly higher in cystic fibrosis patients older than 7 years than in younger patients and in age matched controls. IgG antibody titers measured a second time 11.8 months later in 143 of the 199 patients had increased in 48 (33.6%) patients. In 27 of these 48 patients, who had at least a 2-fold increase in antibody titer, FVC and FEV1 decreased by 9.8% (p<0.05) and 8.3% (p=0.05), respectively, over 45 months. In a comparison group matched for age, sex, and chronicPseudomonas aeruginosa infection but no increase in antibody titers, FVC and FEV1 were unchanged. The results indicate that wild-type adenovirus infections are prevalent in cystic fibrosis patients and that wild-type adenovirus infections in cystic fibrosis patients seem to be associated with deterioration in lung function. These observations may have important implications for efficacy and safety considerations when using adenoviral vectors for gene therapy.

Summary Susceptibilityin vitro of 179 staphylococcal strains from 107 cystic fibrosis patients against 31 antibiotics indicates that only teicoplanin, vancomycin and netilmicin were active against all strains. The use of betalactam antibiotics is impaired by 11.7% of methicillin-resistant strains. The bactericidal kinetics of cephalexin and flucloxacillin as determined in a pharmacody-namic model demonstrates the killing of strains resistant to cephalexin (MIC 8 mg/l to 32 mg/l) by flucloxacillin. For the rational selection of antistaphylococcal antibiotics for cystic fibrosis patients, both the MIC of the isolates and the concentration of the antibotics in cystic fibrosis patients have to be considered.

Summary A microbiological analysis of 102 patients suffering from cystic fibrosis was conducted over a 22 month period. 20 microbial species with the following incidence were identified:Pseudomonas aeruginosa: 83.4%;Candida albicans: 29.4%;Staphylococcus aureus: 24.5%;Staphylococcus epidermidis: 11.8%;Haemophilus influenzae: 11.8%;Streptococcus pneumoniae: 6.9%;Pseudomonas maltophilia: 6.8%;Aspergillus fumigatus: 5.9%. Other species were present in less than 5% of the patients. In the majority of specimens withP. aeruginosa, more than one type (up to six) was detectable. These strains were identical in colony appearance, O-serotype and pyocin-type. Quantitative analysis revealed concentrations of colony-forming units of 107 to 109 forP. aeruginosa, 106 to 108 forP. maltophilia, 104 to 107 forS. aureus, 104 to 106 forS. epidermidis and 104 to 107 forC. albicans in the majority of specimens. Significant differences were observed in the time periods during which the pathogens persisted in the patients. Maximum persistence was observed forP. aeruginosa. P. maltophilia andA. fumigatus had about similar persistence rates, which were lower than those forP. aeruginosa but above those forS. aureus andH. influenzae. S. epidermidis was eliminated within shorter periods thanS. aureus. C. albicans, although the second most frequent microorganism identified, showed a very low persistence rate. The microbiological analysis confirms results from other research centers (high incidence ofP. aeruginosa), but reveals significant regional differences as well (Pseudomonas cepacia not detectable, higher incidence ofP. maltophilia andC. albicans). This underlines the necessity for detailed qualitative and quantitative microbiological analysis of sputa from cystic fibrosis patients as a prerequisite for rational analysis of etiological, epidemiological and therapeutical aspects of cystic fibrosis.

Zusammenfassung Die Wirksamkeit für die 4-Chinolone Ciprofloxacin (CPX) und Ofloxacin (OFX) wurden in einer Kreuzstudie überprüft. 20 ambulante Patienten mit zystischer Fibrose und chronischer Besiedelung der Atemwege mitPseudomonas aeruginosa wurden zehn Tage lang mit OFX, im Anschluß zehn Tage lang mit CPX undvice versa, behandelt. Arzneimittelkonzentrationen in Serum und Expektorat wurden ermittelt, die Patienten anhand klinischer und labormäßiger Parameter überwacht. Die aufgetretenen Nebenwirkungen machten einen Behandlungsabbruch in keinem Fall nötig. Die Serum- und Expektoratkonzentrationen lagen über der minimalen Hemmkonzentration. ObwohlPseudomonas aeruginosa durch die Behandlung nicht eliminiert werden konnte, zeigte sich bei zwei Drittel der Patienten eine klinisch und labormäßig erfaßbare Besserung der Infektion. OFX und CPX sind bei oraler Anwendung wirksam.

Within a 6-year period ten patients with necrotizing enterocolitis (grade II–III; Bell) have been treated at the University Hospital, GBttingen. The following NEC incidences were calculated: birth weight < 1000 g: 2.4% (3/123); 1000–1500 g: 0.6% (2/308); 1501–2000 g: 0.7% (3/436); > 3000 g: 0.006% (2/30000 live births). In all patients onset of necrotizing enterocolitis (NEC) was associated with typical clinical symptoms such as abdominal distension, feeding problems, bloody stools. Only four out of ten patients had positive blood tests of various inflammatory parameters when diagnosed (C-reactive protein, neutrophil count, I/T-ratio). However, increased CRP levels were observed in all patients during the course of the disease (maximum levels: day 2–4 after diagnosis). During primarily conservative therapeutic management only one out of ten patients developed bowel perforation (day 6 after diagnosis) and immediate surgical treatment was carried out. In addition, in three patients who acquired strictures with obstruction of the colon, elective surgery was performed at a postnatal age of 51–77 days. All patients survived NEC without longterm sequelae. We conclude that a primarily conservative therapeutic regimen — whenever perforation and gangrene are absent — may be an alternative to early surgical intervention in NEC.

This report presents a case of infantile multiple system atrophy with probably autosomal recessive inheritance. The female patient developed generalized muscular hypotonia, myoclonias and tonic-clonic seizures at the age of 8 months, followed by gradual development of choreoathetotic hyperkinesia and increasing psychomotor retardation. Metabolic disease was ruled out and the child died of aspiration pneumonia at the age of 5 years. General autopsy was unremarkable, but neuropathological examination showed degeneration of cerebellum, inferior olives, medial thalamus, Clarke's nucleus, anterior horn cells, corticospinal, spinocerebellar tracts, and posterior columns. Immunohistochemically many neurons contained intranuclear and intracytoplasmic ubiquitin-positive inclusions, which did not contain neurofilament or tau epitopes and ultrastructurally consisted of granulofilamentous material. We tentatively classify this case as a form of infantile multiple system atrophy linked to neuronal intranuclear hyaline inclusion disease.

Within a randomized European multicentre trial the time of onset, severity and progression of intracerebral haemorrhages (ICH) were investigated prospectively by serial cranial ultrasonography in 343 ventilated infants with severe respiratory distress syndrome (RDS) following instillation of single or multiple doses of a natural porcine surfactant (Curosurf). In 148/343 infants (43%) ICH was diagnosed (grade I or II: 22%, grade III or IV: 21%). In 26 cases (8%) ICH was present on the ultrasound scan prior to surfactant instillation at a median age of 6h. Incidence and severity of ICH was similar after single- or multiple-dose surfactant treatment. Using a logistic regression model the following risk factors predictive of ICH were defined: low birth weight, allocation to certain hospitals, vaginal delivery, Apgar score≤6, rectal temperature on admission ≤36°C, primary anaemia, acidosis prior to treatment, RDS grade IV in pre-treatment chest films and poor response to surfactant treatment

3720 selected deliveries were studied restrospectively. Toxemia, Rh-constellation, diabetes mellitus, breech presentations, still birth, fetal malformations and deliveries before 37 week gestation (Ultrasound measurements) were excluded. Three main populations were established: Main I, the total of all deliveries, Main II, newborns delivered spontaneously (n=2814), Main III, neonates delivered by vaginal extractions or caesarean sections (n=547).

Objective: To clarify the effectiveness of amoxicillin prophylaxis in the prevention of catheter-related infections. Method: We performed a randomized, controlled, sequential, prospective trial in newborn infants undergoing percutaneous central venous catheterization. Results: Seventy-five infants (median birth weight, 1240 gm; median age at catheter insertion, 3 days) received prophylactic amoxicillin (100 mg/kg per day); 73 infants in the control group (median birth weight, 1170 gm; median age, 2 days) received no routine prophylactic antibiotic treatment. No infant receiving amoxicillin had septicemia, whereas two infants (2.7%) in the control group did; suspected septicemia (positive clinical and laboratory findings but negative blood culture results) was found in 3 infants in the amoxicillin group and in 6 of the control group (not significant). Bacterial contamination of the catheter tip at removal was significantly reduced in the amoxicillin group (13.3% vs 28.8% in control subjects; p <0.05). Negligible differences were found in duration of catheterization (median, 15 days in both groups), or the number of thrombotic (9.3% vs 2.7% in control subjects) and other catheter-related complications between the groups. Conclusion: A low incidence of catheter-related infections can be achieved in neonates with central venous catheters without using prophylaxis with an antibiotic. (J PEDIATR 1995;127:615-9)

Es werden Synthese und Eigenschaften der Phosphaniminato‐Komplexe [ZnCl(NPMe3)]4(1), [ZnH · (NPMe3)]4(2), der Alkinylo‐Derivate [Zn(C≡C–SiMe3)(NPMe3)]4(3), [Zn(C≡C–C≡C–SiMe3)(NPR3)]4[R = Me (4 a), R = Et (4 b)] und [Zn(C≡C–Ph)(NPMe3)]4(5) sowie der Alkenylo‐Zinkkomplexe [Zn(CH=CHMe)(NPR3)]4[R = Me (6 a), R = Et (6 b)] beschrieben, die nach Kristallstrukturanalysen von 1, 3und 4 bHeterocuban‐Strukturen mit nur wenig verzerrten Zn4N4‐Würfelgerüsten haben. Versuche zur Substitution der terminalen Liganden an den Zinkatomen durch Bis(trimethylsilyl)amido‐Gruppen führen zum Abbau der Heterocubane und Bildung des dimeren Komplexes [Zn(μ2‐NPEt3){N(SiMe3)2}]2(7) und des dreikernigen Derivates [Zn3(μ2‐NPMe3)4{N(SiMe3)2}2] (8), in dem das zentrale Zinkatom spirocyclisch von den vier N‐Atomen der NPEt3–‐Gruppen umgeben ist. Auch 7und 8werden durch Kristallstrukturanalysen charakterisiert.

Zusammenfassung Anhand der Unterlagen einer weiterbildungsberechtigten kieferorthopädischen Fachpraxis wird der Vergleich angestellt zwischen einer Patientengruppe (X), bei der eine Prämolarenextraktion in allen vier Quadranten durchgeführt wurde (n=104), und einer zweiten Gruppe, (N), bei der trotz ursprünglicher Erwägung auf eine Zahnentfernung verzichtet wurde (n=103). In der Extraktionsgruppe stand die ausgeprägtere Anomalie zur Korrektur an. Die Erfolgsbilanz gestaltet sich annähernd ausgeglichen, wobei die durchschnittliche Behandlungsdauer, Zahl und Umfang von Wurzelresorptionen sowie der Restlückenbefund im Nichtextraktionsgut günstiger ausfielen, verminderter Headgeareinsatz, FRS-Werte und fehlende Engstände jedoch für die Extraktionsentscheidung sprachen. Bei sachkundigem Umgang mit der festsitzenden Apparatur scheint die systematische Extraktion auch im Grenzfalle vertretbar.

The homoleptic complexes hexakis(η¹-phosphinine)molybdenum 10 and hexakis(η¹-phosphinine)tungsten 11 have been prepared via reduction of suitable metal halides with magnesium or zinc in order to explore trends in the triad (η¹-C5H5E)6M, M = Cr, Mo, W. According to X-ray crystal structure determinations, 10 and 11 are isostructural and show almost ideal octahedral geometry of the metal−phosphorus core. The bond distances d(M−P) are relatively short in comparison to other homoleptic phosphane complexes of Mo and W; they follow the expected order:  Cr−P (2.26 Å, 2) &lt; Mo−P (2.38 Å, 10) ≈ W−P (2.37 Å, 11). The NMR data exhibit the same trends upon the η¹-coordination of phosphinine as hexakis(η¹-phosphinine)chromium 2, but the change of the central metal from Cr to W results in an increased shielding of the neighboring atoms (P, ortho-H, and C) of the ligands. The UV−vis spectra of 10 and 11 in comparison to 2 display a continuous hypsochromic shift in the MLCT region. Conversely, the redox potentials for the couples ML6^(+/0), which are increasingly anodic following the sequence Cr &lt; W &lt; Mo, show a discontinuous gradation.

In an international multicenter trial infants with clinical and radiological signs of severe RDS (age 2-15 h, birthweight 700-2,000 g, mechanical ventilation, FiO2 ≧ 0.6, no complicating disease) were randomized to receive either a single dose (n = 176) or up to three subsequent doses (n = 167) of a natural porcine surfactant (Curosurf). Using a logistic regression model, the effects of therapy, birthweight, sex, hospital and other clinical factors on survival and various outcome parameters were evaluated. Mortality (13 vs. 21 %, p < 0.05) and the incidence of pneumothorax (9 vs. 18%, p < 0.01) were significantly lower in the multiple-dose group. Low birthweight, hospital allocation, low Apgar score and initial disease severity were associated with an increased mortality. Low birthweight, hypothermia (admission temperature < 36°C) and acidosis (pH < 7.25) prior to surfactant treatment could be identified as risk factors for the development of intracranial hemorrhage.

The results of 179 oral d-xylose tests (d-xt) performed in 145 children aged 3 months to 131/2 years were compared with the dissecting microscope findings of the jejunal biopsy specimens. All but one of 68 subtotal villous atrophies and 3 out of 18 partial villous atrophies were gluten-induced. The majority of the d-xt (57%) of children in the age group of 3 months to 3 years with subtotal villous atrophy were found to yield 1–9% of recovered d-xylose, with a significant difference from the two other morphological groups, partial villous atrophy and normal mucosa. All three groups overlapped in the range of 10 to 15% d-xt. This means that only a d-xt of less than 10% is indicative of celiac disease. Some d-xt values above 15% in children under 3 years of age with subtotal villous atrophy were the result of a consciously or unconsciously given gluten-free diet prior to biopsy. The regeneration of the mucosa in the upper small intestine proceeds more slowly than the normalization of the d-xt. In early childhood the d-xt may be of value in that it may provide evidence of successful gluten-free diet in the first phase of therapy. Villous atrophy in the older child with celiac disease recurring after reintroduction of gluten was never detected with the d-xt. There is no difference between the distribution of d-xt in children with normal mucosa and those with partial villous atrophy. The d-xylose recovery in the urine of children with normal mucosa increased with the children's age.

The half-sandwich high-valent niobium(V) phosphoniomethylidyne complex [CpNb{CPPh3}Cl2] (4) was obtained by the transylidation reaction of CpNbCl4 with 3 equiv of Ph3P&dbd;CH2. The X-ray structure shows a three-legged piano-stool geometry. The mechanism of formation is discussed.

The rhenium(VII) phosphonio−methylidyne complex [Re(N^tBu){C−P(NEt2)3}Cl3] (3) is obtained via interaction of an imido ligand in [Re(N^tBu)2Cl3] (1) with the phosphorus ylide (Et2N)3P&dbd;CH2. The isolation of all the intermediates and products of this reaction allows us to postulate a mechanism in which the amine, formally generated from the imido ligand, is trapped by the Lewis acid 1 with formation of [Re(N^tBu)3Cl] (4) and [(Et2N)3P−CH3]⁺[Re(N^tBu)2Cl4]^- (6). 3 and 6 have been structurally characterized.

[5]Trovacenol (4^•) prepared according to the sequence (C7H7)V(C5H5) (1^•)→ (C7H7)V(C5H4OSiMe3) (5^•) → (C7H7)V(C5H4OH) (4^•) in the crystal adopts a sheet structure. The sheets consist of parallel chains of hydrogen bonds, graph set C(4), to which the [5]trovacenyl groups are connected, forming double layers. Packing of the trovacene units on both sides of the (···O−H···O−H···)n spines displays a herringbone pattern. In this way O−H···O as well as (C7H7)H···π(C5H5) hydrogen bonding is optimized. This study represents the first full structural characterization of a metallocenol.