ABSTRACT. Despite the serious pulmonary manifestaintact animal could be initiated by a direct interaction tions of early onset group B streptococcal (GBS) sepsis, it between GBS and resident lung cells without obligatory is not known whether the organism distributes into lung participation by other organ systems. (Pediatr Res 27: tissue and whether adverse pulmonary hemodynamic ab-344-348,1990) normalities relate to an interaction between the organism and target cells in the pulmonary vascular bed. AccordAbbreviations ingly, this study evaluated the distribution and fate of GBS in the lung, liver, and spleen of anesthetized infant piglets GBS, group B streptococcus and in isolated, salt solution-perfused piglet lung prepara-HBSS, Hanks' balanced salt solution tions. GBS were radiolabeled with lllIndium-oxine and cfu, colony-forming unit infused at a dose of 108 organisms/kg/min for 15 min into Ppa, pulmonary arterial pressure anesthetized piglets ranging in age from 5-10 d. Forty-five Pla, left atrial pressure min after termination of the infusion, animals were killed Rt, total resistance and specimens of lung, liver, spleen, and blood were excised Ra, arterial resistance and the relative deposition and viability of GBS were Rv, venous resistance determined. Most of the recovered bacteria were detected Pdo, double occlusion pressure in the lung (53.2 f 3.9%) followed by the liver (41.4 f 2.0%) and spleen (2.2 f 0.38%). GBS detected in the blood was estimated to be only 3.2 2 1.0% of the infused dose. Viability of GBS was least in the lung (21.4 2 2.6%)The question is straight-forward: Does GBS promote pulmorelative to the liver (45.7 f 11.2%) and spleen (83.4 +: nary hypertension in the newborn through interaction with a 19.5%). After a 60-min GBS infusion, transmission elec-target cell in the lung? The concept that GBS-induced pulmonary tron microscopy localized the organism within pulmonary hypertension results from an interaction with resident lung cells intravascular macrophages in the lung; there was no evi-is intuitively appealing. The lung contains several cell types that dence for bacterial interaction with either neutrophils or could serve as transducers of the pulmonary hemodynamic reendothelial cells. In the liver, GBS was found exclusively sponse to GBS. For example, the lung contains a substantial in Kupffer cells. In isolated piglet lungs perfused at a population of marginated neutrophils, a phagocytic cell known constant flow rate with blood-free physiologic salt solution, to elaborate various mediators incriminated in the response to GBS (lo6 to 10' organisms/mL) provoked concentration-GBS (I), including thromboxane AZ, sulfidopeptide leukotrienes, dependent increases in pulmonary vascular resistance. and toxic oxygen radicals (2-4). Pulmonary vascular endothelial Transmission electron microscopic examination of isolated cells also exhibit phagocytic activity ( 5 , 6) and produce eicosalungs indicated that GBS was localized within pulmonary noids with chemoattractant activity for neutrophils (7)....

Measurements of electron conversion coe%cients for high spin states of ' Nd are reported. Parities are assigned for these states, and the results are used to test a weak coupling model for 143 gd

The level structure of ' 'Nd has been studied via the ' Te("0,5n) reaction. A level spectrum up to 5.3 MeV in excitation energy has been constructed from y-y coincidence spectra and y-ray angular distributions. In addition to the single particle 1.228 MeV '2 + state, others states arising from three-and five-quasiparticle configurations are identified, and spins and parities are suggested for these states.Results from studies of ' Nd using various reactions' show that the low lying states with energies of less than 1.5 MeV are primarily single 3p, /2, li, 3/2 and 1h9/2 neutron states, while states above that energy have more complicated structure. It was proposed more than a decade ago that near-yrast states at energies between 1.5 and 3.5 MeV observed via the ' Ce(a, 3n) reaction were positive-parity three-quasiparticle (3qp) states. The proposal of positive parity for these higher lying states was based on the positive-parity assignments ' for yrast states in the isotone ' Gd. However, in a recent work the positive-parity assignments for yrast states in ' Nd in the energy range 1.5 -2.2 MeV were questioned and fivequasiparticle (Sqp) structure for states above 3.5 MeV was proposed.In a zero-order weak coupling model, a state in an odd-3 nucleus is interpreted in terms of a state in an adjacent even-even core nucleus and a valence particle. This model is most useful when there is a single valence particle outside of a closed shell. A good example is the case of the N=83 nucleus ' Gd, where the positiveparity 3qp states can be explained in terms of the weak coupling of an f7/p neutron to the yrast negative-parity states of the ' Gd core. ' It should be possible to associated states of the N=83 nucleus ' Nd with states of the Nd core using the same approach.The objective of this work is to investigate the properties of the ' Nd states populated in the ' Te(' 0,5n) reaction. This heavy ion-induced reaction strongly populates near-yrast high angular momentum states. Spin assignments are made using the measured angular distributions; parities are suggested by means of the zero-order weak coupling model. The ' Te(' 0,5n) experiments were performed using the Florida State University FN Tandem Van de Graaff accelerator and the Superconducting Linear Accelerator.For the y-y coincidence experiment, three coaxial hyperpure Ge detectors, located 15 cm from the target and at 90 relative to the beam direction, collected y rays produced in a 500 mg/cm target enriched to 98.6%%uo in ' Te.The detectors had energy resolutions (full width at half maximum) of 2. 1 keV or better at 1332 keV and efficiencies of 23% relative to a 3-in X3-in NaI(T1) detector. The Ge detectors were inserted into BGO Compton suppressors, which reduced the Compton scattering background from a Co source by approximately 75%.

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