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Notes: Abstract We performed a multicenter prospective randomized controlled trial to determine the efficacy and safety of the surfactant preparation, Survanta (Abbott Laboratories, Chicago, USA), for 750–1750 g infants with idiopathic respiratory distress syndrome, (IRDS) receiving assisted ventilation with 40% or more oxygen. One hundred and six eligible infants from the eight participating centers were randomly assigned between March 1986 and June 1987 to receive either surfactant (100 mg phospholipid/kg, 4 ml/kg) or air (4 ml/kg) administered into the trachea within 8 h of brith (median time of treatment 6.2 h, range 3.2–9.1 h). The study was stopped before enrollment was completed at the request of the United States Food and Drug Administration when significant differences were observed in incidence of periventricular-intraventricular hemorrhage (PIH), between the surfactant treated and control infants. Surfactant treated infants had larger average increases in the arterial-alveolar oxygen ratio, (a/A ratio) (P〈0.0001), and larger average decreases in FiO2 (P〈0.0001) and mean airway pressure, (MAP) (P〈0.017) than controls over the 48 h following treatment. The magnitude of the differences between the surfactant and control groups were 0.19 (SE=0.03) for a/A ratio, −0.28 (SE=0.04) for FiO2 and −1.7 cm H2O (SE=0.70) for MAP. The clinical status on days 7 and 28 after treatment was classified using four predefined ordered categories: (1) no respiratory support; (2) supplemental O2 with or without continuous positive airway pressure (CPAP); (3) intermittent mandatory ventilation; and (4) death. There were no statistically significant differences in the status categories on days 7 or 28 between surfactant and control infants. There were no significant differences between the groups with respect to the incidence of patent ductus arteriosus, bronchopulmonary dysplasia, necrotizing entero-colitis, air leaks or death. There was a statistically significant difference between treated and control infants in the frequency and severity of periventricular-intraventricular hemorrhage (PIH) (Cochran-Mantel-Haenszelχ 2adj=6.36,P=0.01). Hemorrhages occurred in 59.6% of surfactant treated infants and 26.9% of controls. Severe hemorrhages (grades 3 or 4) occurred in 38.5% of surfactant treated infants and 15.4% of controls (χ 2adj=4.01,P=0.045). We conclude that the intratracheal administration of Survanta prior to 8 h of age to infants with IRDS receiving assisted ventilation with 40% or more oxygen results in a reduction in the severity of respiratory distress during the 48 h after therapy. Because of the difference in incidence of PIH between surfactant and control infants in this study, we recommend that future clinical trials of surfactant include more frequent prospective serial ultrasound evaluations for diagnosis of hemorrhage.

Notes: Abstract— For the GABA shunt to operate in rivo, GABA must be able to enter brain mitochondria. GABA causes reduction of intra-mitochondrial NAD+; glutamate or 2-oxoglutarate stimulate this reduction at concentrations at which they do not themselves cause reduction. This stimulation is not abolished by Triton X-100. The rates of swelling of brain and liver mitochondria are similar in iso-osmotic GABA and in several analogues. The rate of swelling is proportional to the concentration of GABA in the iso-osmotic suspension medium. GABA penetrates 60% of the mitochondrial matrix volume, this value is unaffected by energizing the mitochondria. The activity of GABA-oxoglutarate aminotransferase is not latent. We conclude that GABA diffuses into both brain and liver mitochondria as a species with no net charge at rates which are able to sustain maximum activity of the GABA shunt.

Notes: We have developed a quasicontinuous crucible free zone melting method for texturing YBCO bulk material. Dense sintered rods with a length of 10 cm were partially molten in the hot zone of a 5 zone furnace and recrystallized in the large temperature gradient (140 °C/cm) limiting this zone. Suitable additions of Y2BaCuO5 (20 mol %) and PtO2 (1 wt %) to the starting material and a growth rate of not more than 1 mm/h were necessary to obtain stable growth conditions. After natural grain selection we obtained 8-cm-long rods with a uniform orientation of the crystallographic axes within 2°. The angle between c direction and rod axis typically was 55°. The critical current density at 77 K measured with continuous current over a length of 4.5 cm was 1.3×104 A/cm2 in zero field and 8×103 A/cm2 in 0.5 T. These values confirm the absence of grain boundaries.

Notes: Abstract In a prospective randomized study using a canine model, we compared the use of monopolar electrosurgery (EC) (n=23) and the Nd:YAG Contact Laser™ (CL) (n=21) on intra- and postoperative morbidity in laparoscopic large-bowel resection. In EC, cutting was performed with scissors and coagulation was performed with electrosurgery. In CL, cutting and coagulation were carried out with the Nd:YAG Contact Laser™. Laparoscopic oncologic right colectomy with intraperitoneal ileocolic stapled anastomosis was performed in all dogs. Intraoperative smoke development, difficulty of dissection, hemostasis, and postoperative adhesions were judged using a five-point score. Two weeks after surgery, all dogs were sacrificed and zoopsy was carried out. Three dogs died postoperatively from pneumonia and one from an anastomotic leak. There were no other postoperative complications. Operative time was 135 min (range 105–180) in the CL group and 145 min (range 60–210) in the EC group. Intraoperative smoke development, difficulty of dissection, and postoperative amount of adhesions were not different between groups (P〉0.05). Hemostasis in the CL group (median score of 1, range 1–2) was significantly better (P=0.01) than in the EC group (median score of 2, range 1–5). Scissors and electrosurgery as well as Nd:YAG Contact Laser™ can be used successfully in intestinal laparoscopic surgery. Although the use of the Contact Laser™ did not cause less postoperative morbidity than the conventional method, there was significantly better hemostasis using the Nd:YAG Contact Laser™.

Notes: Summary Lytic transition of Epstein-Barr virus (EBV) is initiated by distinct immediate early regulators of the viral cycle, in synchronization to temporary, permissive conditions during host cell differentiation. We developed eukaryotic vectors suitable to imitate the processes involved in lytic transition in cell culture systems. Two stable B cell lines were established: R59Z activator cells were used to induce lytic EBV expression in a constitutive manner by the production of the BZLF 1trans-activator (Zta). R7-57 reporter cells, on the other hand, signaled induced activity of the lytic origin of EBV replication (oriLyt). Different modes, like chemical induction, lytic superinfection with EBV and single genetrans-activation converted the recombinant oriLyt element in R7-57 reporter cells. BZLF 1, transiently expressed in R7-57 reporter cells, was the only EBVtrans-activator found, sufficient in inducing the viral lytic cycle. Basing on these experiments,trans-cellular activation of EBV was tested by cocultivation of BZLF 1-expressing R59Z activator cells with the R7-57 reporter line. No lytic effect on the reporter cells could be measured, neither by cocultivation of activator cells nor by coincubation of BZLF 1-containing cell lysates. Latency breaking activity, however, was transferred from activator to reporter cells when active, exogenous virus was added. The cell system described in these experiments provides a tool for the detection of EBV reactivation and demonstrates the potential of the lytic regulatory gene BZLF 1.

Notes: Summary The photosensitivity of cystine and the aromatic amino acids tryptophan, tyrosine and phenylalanine in different proteins, in aqueous solution and in the adsorbed (solid) state is compared with the photosensitivity of these amino acids in thermal polymers ofα-amino acids. The photosensitivity of cystine in the absence of chromophoric groups is largely independent of the amino acid composition, primary structure, or conformation of the polymer. The interaction between the “sensitizer” (aromatic amino acid residues), and cystine, however, is largely dependent on the conformation of the polymer if energy or charge transfer is involved. The effects of tryptophan photolysis products (solvated electrons) appear to be largely independent of the conformational state.

Notes: Summary Irradiation of thermal polymers ofα-amino acids with X-rays in the solid state produces a significantly increased destruction of tryptophan, histidine, cystine, lysine and methionine as compared with the response of constituent amino acids in proteins. These results are discussed with respect to related results obtained by irradiation of dry films of amino acid mixtures which indicate an even stronger energy or charge transfer towards the four amino acids mentioned. The results are also discussed with respect to the radiation sensitivity of constituent amino acids in proteins and the inactivation of enzymes.

Notes: Abstract Large CeCu2Si2 single crystals have been grown with the cold boat technique. The transition temperature to the superconducting state is strongly dependent on the copper concentration in the crystal. Annealing under copper atmosphere shifts the transition temperature to higher values.