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Notes: Abstract Islet autotransplantation offers the potential for preventing the surgically induced diabetes that is an inevitable consequence of total pancreatectomy. This paper describes the first islet autotransplant programme in the United Kingdom and the first series in the world to use the spleen as a site for the islet graft. Over an 11 month period, 7 patients underwent total pancreatectomy for chronic pancreatitis combined with a simultaneous islet autotransplant. All 7 patients had normal glucose-tolerance levels and normal C-peptide levels pre-operatively. In 6 patients, islets were embolized into the liver via the portal vein (median transplanted volume=8.5 ml). In addition, 3 patients received islets into the splenic sinusoids via a short gastric vein (median transplanted volume=4 ml). One patient received islets into the spleen alone. One patient died of a stroke 4 weeks post transplantation. Two patients have achieved insulin independence, with a further two patients achieving ”transient” insulin independence (〈1 month). The remaining 2 patients, although requiring reduced insulin doses, have not achieved insulin-independence. However, all patients have C-peptide levels within the normal range. In trying to explain these findings, split proinsulin levels were measured and found to be elevated. High levels of split proinsulin cross react with the C-peptide assay and this would explain the falsely elevated C-peptide levels. Indeed insulin levels in these patients were all below the normal range. These findings would suggest that the use of C-peptide levels as the ”gold standard” for monitoring islet autograft function, may require reappraisal.

Notes: We compute the braiding for the "principal gradation" of Uq(sl2&dbgcaret;) for |q|=1 from first principles, starting from the idea of a rigid braided tensor category. It is not necessary to assume either the crossing or the unitarity condition from S-matrix theory. We demonstrate the uniqueness of the normalization of the braiding under certain analyticity assumptions, and show that its convergence is critically dependent on the number theoretic properties of the number τ in the deformation parameter q=e2πiτ. We also examine the convergence using probability, assuming a uniform distribution for q on the unit circle. © 2001 American Institute of Physics.

Notes: 1. The mechanism of C5a des Arg-induced airway hyper-responsiveness in rabbits was investigated.2. Airway smooth muscle from rabbits which had been pretreated in vivo, was studied in vitro. Tracheal rings, segmental bronchial rings, subsegmental bronchial spirals and lung parenchymal strips were all prepared from each rabbit lung.3. Although C5a des Arg produces hyper-responsiveness to histamine in vivo, which is inhibited by indomethacin, the airway smooth muscle responses in vitro from control, C5a des Arg and C5a des Arg plus indomethacin pretreated rabbits did not differ.4. The neutrophil counts in the tracheal and subsegmental bronchial specimens were increased in the C5a des Arg-treated group. Indomethacin significantly (P〈0.05) inhibited the neutrophil influx in the subsegmental bronchi.5. It is concluded that intrinsic smooth muscle function is unaltered following C5a des Arg-induced hyper-responsiveness in vivo.

Notes: Although it has been postulated that inflammatory cells cause the bronchial hyper-responsiveness which is diagnostic of asthma [1], until recently there has been little direct evidence of such a link. We have recently shown that calcium ionophore-activated human neutrophils and eosinophils can induce a state of human airway hyperresponsiveness in vitro [2]. In this study we have shown that the anti-inflammatory agent nedocromil sodium, 10-7m, inhibited the hyperresponsiveness induced by products released from ionophore activated neutrophils but did not inhibit the release of leukotriene B4 from the same cells. Neutrophil-induced bronchial hyperresponsiveness was also inhibited by pre-treatment of the bronchial tissues with a thromboxane A2 and prostaglandin receptor antagonist, GR32191,10-7m. These findings indicate that cyclooxygenase products are involved in bronchial hyperresponsiveness induced by inflammatory cell products in vitro and that their release can be inhibited by nedocromil sodium.

Notes: A series of experiments was performed with an Applied-B ion diode on the Particle Beam Fusion Accelerator-I, with peak voltage, current, and power of approximately 1.8 MV, 6 MA, and 6 TW, respectively. The purpose of these experiments was to explore issues of scaling of Applied-B diode operation from the sub-TW level on single module accelerators to the multi-TW level on a low impedance, self-magnetically insulated, multimodule accelerator. This is an essential step in the development of the 100-TW level light ion beam driver required for inertial confinement fusion. The accelerator and the diode are viewed as a whole because the power pulse delivered by the 36 imperfectly synchronized magnetically insulated transmission lines to the single diode affects module addition, diode operation, and ion beam focusability. We studied electrical coupling between the accelerator and the diode, power flow symmetry, the ionic composition of the beam, and the focusability of the proton component of the beam. Scaling of the diode impedance behavior and beam quality with electrical drive power is obtained from comparison with lower-power experiments.The diode impedance lifetime was about 10 ns, several times shorter than for lower-power experiments. Azimuthal and top-to-bottom variations of the diode and ion currents were found to be approximately ±10%, compared with an estimated requirement of 5%–7% uniformity to avoid focal blurring by self-magnetic field effects. The ion production efficiency was 80%–90%. However, only 50%±10% of the ion current was carried by protons; the balance was carried by multiply charged carbon and oxygen ions. Activation measurements showed a proton beam energy of approximately 50 kJ. A gas cell filled with 5 Torr of argon was used for beam transport. The macroscopic divergence was 15±10 mrad and the microscopic divergence was 20±15 mrad, values that are similar to those from lower-power experiments. A model of beam focusing is formulated that predicts the proton charge focused onto 0.47-cm radius lithium targets, taking into account beam purity, magnetic bending, small-angle multiple scattering, and intrinsic divergence. The model results and activation measurements of the number of protons focused onto targets agree, and indicate that the spatially averaged (over about 3 cm2) peak focal power was about 0.5 TW/cm.2 The most important limitations on power concentration were found to be the low proton content of the beam, the short impedance lifetime of the diode, and the asymmetric current feed of the accelerator. The short impedance lifetime limited the power coupled to the diode, and caused the voltage at peak ion power to be low, which exacerbates the small-angle scattering problem. The asymmetric feed caused focal blurring through nonuniform self-magnetic bending. At least partly because of the experience gained with low impedance beams during these experiments, the next generation accelerator, the 100-TW Particle Beam Fusion Accelerator-II, has been configured to produce a 25–30-MV Li+ beam rather than a 5-MV proton beam. off

Notes: We have studied the optical properties of cosputtered XMnSb (X=Cu,Ni,Pt) thin films using light transmission, reflection, and spectroscopic ellipsometry. We observed a feature in the transmission spectra suggestive of a band gap of energy ∼1.5–1.7 eV for PtMnSb, ∼1.1 eV for NiMnSb and ∼0.8 eV for CuMnSb. This behavior is consistent with predictions of the half metallic ferromagnetic state in PtMnSb and NiMnSb. The values for PtMnSb and NiMnSb are larger than the ones previously reported by other authors on bulk polished samples. We interpret this discrepancy as due to surface contamination of the bulk samples or nonstoichiometry in our films. © 1997 American Institute of Physics.

Notes: To investigate the possibility of using the half-metallic ferromagnet PtMnSb in giant magnetoresistance (GMR) applications, we have examined the surface roughness, structural uniformity, mean-free path, and lattice disorder of sputtered epitaxial PtMnSb(111) films on Al2O3(0001) in the range 85 Å≤t≤1100 Å. Atomic force microscopy revealed the films to be very flat, with an rms roughness of (approximate)3 Å for thicknesses below 100 Å. X-ray diffraction and vibrating sample magnetometry indicated that the entire volume of the single-phase films were ferromagnetic (Ms(approximate)500 emu/cm3), with no evidence for a nonstoichiometric or oxidized surface layer. Hall-effect measurements and fits to resistivity versus thickness data by surface scattering models yielded mean-free-path values of 18.4 and 80–100 Å, respectively. Atomic site disorder was estimated at (approximate)10% from structure factor analysis of integrated x-ray peak intensities. These results suggest that bulk properties will play the largest role in determining the effectiveness of PtMnSb in GMR applications. © 1997 American Institute of Physics.