Calcium puffs are generic InsP₃-activated elementary calcium signals and are downregulated by prolonged hormonal stimulation to inhibit cellular calcium responses

Elementary Ca2+ signals, such as "Ca2+ puffs", which arise from the activation of inositol 1,4,5-trisphosphate receptors, are building blocks for local and global Ca2+ signalling. We characterized Ca2+ puffs in six cell types that expressed differing ratios of the three inositol 1,4,5-trisphosphate receptor isoforms. The amplitudes, spatial spreads and kinetics of the events were similar in each of the cell types. The resemblance of Ca2+ puffs in these cell types suggests that they are a generic elementary Ca2+ signal and, furthermore, that the different inositol 1,4,5-trisphosphate isoforms are functionally redundant at the level of subcellular Ca2+ signalling. Hormonal stimulation of SH-SY5Y neuroblastoma cells and HeLa cells for several hours downregulated inositol 1,4,5-trisphosphate expression and concomitantly altered the properties of the Ca2+ puffs. The amplitude and duration of Ca2+ puffs were substantially reduced. In addition, the number of Ca2+ puff sites active during the onset of a Ca2+ wave declined. The consequence of the changes in Ca2+ puff properties was that cells displayed a lower propensity to trigger regenerative Ca2+ waves. Therefore, Ca2+ puffs underlie inositol 1,4,5-trisphosphate signalling in diverse cell types and are focal points for regulation of cellular responses

Measurement of ion emission from plasmas obtained with a 600 fs KrF laser

Ion emission from plasmas obtained by the use of a 600 fs, 36 mJ KrF laser operating at 248 nm was measured and analysed for a variety of targets at different laser intensities. The intensity was set by changing the distance between the focusing lens and the target. It was found that the ions emitted originate from impurities and ions from the bulk of the target can be produced only in the subsequent shots. Proton emission was identified from some targets, but the energy of the protons was low (less than 12 keV). A new silicon carbide semiconductor detector proved to be applicable for the collection of the ions

Multiply charged ions from iodine laser-produced plasma of medium- and high-Z targets

Maximum charge states of ions registered in the far expansion zone from laser-produced plasma of Al, Co, Ni, Cu, Ta, W, Pt, Au, Pb, and Bi are presented. The Thomson parabola spectrometer was used to display a general view of the ion species of an expanding plasma while detailed ion charge-energy spectra were determined by the cylindrical electrostatic ion energy analyzer. The current densities of highly charged ion groups above 20 mA/cm2 were measured by use of an ion collector at a distance of 1 m from the target. The photodissociation iodine laser system PERUN (λ = 1.315 μm, power density up to 1015 W cm−2) was employed as a drive

Ion production by lasers using high-power densities in a near infrared region

Results are presented of experiments on ion production from Ta targets using a short pulse (350-600 ps in focus) illumination with focal power densities exceeding 1014 Wcm-2 at the wavelength of an iodine photodissociation laser (1.315 μm) and its harmonics. Strong evidence of the existence of tantalum ions with the charge state +45 near the target surface was obtained by X-ray spectroscopy methods. The particle diagnostics point to the existence of frozen high charge states (4 MeV) for the highest observed charge states. A tentative theoretical explanation of the observed anomalous charge state freezing phenomenon in the expanding plasma produced by a subnanosecond laser pulse is give

Safety of Intraperitoneal Injection of Adipose Tissue-Derived Autologous Mesenchymal Stem Cells in Cats

BACKGROUND: Chronic inflammatory diseases are common in cats and mesenchymal stem cells (MSC) are a promising therapeutic approach for management of these disorders. The purpose of this study was to evaluate the safety of intraperitoneal injection of MSC in cats. HYPOTHESIS: Intrapertioneal injection of autologous MSC in cats is safe. ANIMALS: Ten healthy adult purpose‐bred cats. METHODS: Mesenchymal stem cells were isolated from subcutaneous adipose tissue collected during ovariohysterectomy and characterized for expression of CD90, CD105 and CD44 and trilineage differentiation. Three weeks postoperatively a complete blood count, serum chemistry profile, urinalysis, and abdominal ultrasound were performed. Five cats then received 1 × 10(6) of autologous MSC/kg of body weight intraperitoneally with ultrasound guidance; 5 additional cats were sham injected. Cats were monitored for 6 weeks with daily physical examinations and weekly clinicopathological evaluations. Abdominal ultrasonography was repeated at weeks 1 and 5 after injection. RESULTS: Serious adverse effects were not observed in any MSC‐injected cat. Two animals developed transient lethargy and decreased activity. Jejunal lymph node size was increased in MSC‐injected cats compared to controls at weeks 1 (1.38 ± 0.25 versus 0.88 ± 0.25 cm(2); P = .036) and 5 (1.75 ± 0.82 versus 0.79 ± 0.12 cm(2); P = .047). A hyperechoic renal segmental cortical lesion was observed in 1 MSC‐injected cat. CONCLUSIONS AND CLINICAL RELEVANCE: Intraperitoneal MSC injection was well tolerated with only mild, self‐limiting adverse effects being observed in 2 cats. This route provides a safe means of administration for cell‐based treatment in cats