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Notes: In pure oxygen at moderate temperatures of 200 °C, an fcc C60 transforms into amorphous carbon-oxygen compounds and the icosahedral C60 molecular structure is destroyed. The maximum oxygen uptake of pure C60, O/C60, is 12. Isothermal TGA transformation curves are sigmoid-shaped with the kinetic exponent n∼5/2 which conforms with a two-dimensional nucleation and growth mode. The heat of formation for the carbon-oxygen compounds is 90 kcal/mol O, and the formation energy for the reaction: 60C (graphite)→C60 molecule is estimated to be ∼600 kcal/mol.

Notes: Two patients with clinically significant immunoglobulin E (IgE) mediated reactions to cow's milk which occur only under special circumstances are described. Although double-blind, placebo-controlled food challenges or open food challenges are generally very helpful, certain patients who react only under special circumstances might be missed when these office tests are used. The two reported incidences occurred in older children who seemed to outgrow their cow-milk allergy but still had clinically significant allergic reactions under certain circumstances.

Notes: The non-steroidal anti-inflammatory drug(NSAID) naproxen was studied in 11 beagle dogs over a 13-month period to determine its effect on the progression of periodontitis. Following a 6-month pretreatment period, 5 dogs received naproxen daily at a dosage of 2.0 mg/kg for 1 month, then 0.2 mg/kg for 6 months. Six control dogs received a gelatin capsule daily as placebo. Standardized radiographs were used to measure the rate of bone loss during the pretreatment and treatment periods. In the control dogs, the rate of bone loss was seen to increase during the treatment period although the increase was not statistically significant. In dogs treated daily with naproxen, the rate of bone loss in the treatment period was significantly less at 4 months of treatment; however, at 7 months the difference, though lower than pretreatment rate, was not significant. When the percent change in rate of bone loss during the overall 7-month treatment period was compared with pretreatment rate, the control dogs demonstrated a 38% increase in rate of bone loss during the treatment period contrasting with a 61% decrease in bone loss rate in naproxen-treated dogs. The data indicate that the non-steroidal anti-inflammatory drug naproxen can significantly inhibit alveolar bone loss in beagles. At 4 months of treatment the rate of bone loss in the naproxen-treated dogs was significantly less than pretreatment, but at 7 months of treatment the rate was no longer statistically significantly less than baseline. This probably reflects a dose response to naproxen treatment for, after 30 days of the treatment period, the naproxen dosage was reduced 10-fold due to tolerance by the beagle.

Notes: We studied the reactivity of monoclonal antibodies (MAbs) 17.13 and 63.12 with normal and diseased human oral mucosa by means of the immunoperoxidase technique. The specimens included: 22 normal oral tissues, 20 benign tumors, 17 lichen planus, 23 focal keratosis and epithelial hyperplasias, 18 proliferative verrucous leukoplakias, 20 dysplasias, and 21 squamous cell carcinomas. In most cases of normal mucosa and benign lesions, MAb 17.13 stained basal epithelial cells only, whereas MAb 63.12 stained all cell layers above the basal cells. In the premalignant and malignant lesions MAb 17.13 stained above the basal cells and MAb 63.12 either stained areas not stained by MAb 17.13 or the staining was absent. Based on the different staining patterns observed, there appears to be a potential value of these new reagents in diagnostic histopathology regarding specimens with equivocal cellular morphology.

Notes: We have characterized a monoclonal antibody (AT389), produced by immunization of mice with 4-day-old avian Concanavalin A blasts, which recognizes a 38 40 kDa homodimer present on the surface of all chicken T cells. AT389 increased the spontaneous and IL-2-driven proliferation of 3-day-old T-cell blasts. This antibody, in synergy with IL-2, increased cellular proliferation and cell survival of T-cell blasts over time. Together, these data suggest that AT389 recognizes a surface protein on avian T cells which may be related to known stimulatory surface markers on mammalian T cells.

Notes: Summary Hydrostatic and nonhydrostatic simulation models are employed to study the intensification of a terrain drag-induced dryline. The study develops a multi-stage theory for the evolution of the dryline including the concentration of potential vorticity accompanying meso-gamma scale dryline “bulges”. The numerical simulations indicate three fundamental stages of dryline intensification all of which are either directly or indirectly a result of the terrain-drag on the mid/upper-tropospheric jet stream by the Front Range of the Colorado Rocky Mountains. The first stage involves the downward momentum flux accompanying a large amplitude hydrostatic mountain wave which induces a downslope windstorm along the lee slopes. The surge of momentum (i.e., the dry, warm air associated with the downslope windstorm) propagates down the leeslope and modifies an existing weak dryline boundary. As the downslope windstorm initiates an undular bore along the lee slopes, the high momentum gradient which propagates downstream accompanying the bore, as well as the strong lower tropospheric sinking motions ahead of the bore, contract the scale of the surface moisture boundary between the dry air from above the leeslope and the moist air over the High Plains. This process further strengthens the dryline. The second stage involves the coupling of the terrain drag-induced along-stream ageostrophic front within the midtroposphere to the boundary layer through a thermally-indirect circulation. As the along-stream ageostrophic circulation intensifies within the middle troposphere down-stream from the mountain wave, sinking air parcels originating above 40 kPa descend to below 60 kPa over the High Plains where surface pressures are, only ∼85 kPa. These descending air parcels within the upstream branch of the along-stream ageostrophic thermally-indirect circulation contain high values of momentum and very low dewpoint values. As the planetary boundary layer (PBL) deepens due to surface warming during the morning hours, momentum and dry air from the midtropospheric along-stream ageostrophic front are entrained into the PBL. This process amplifies the bore-induced hydrostatic dryline bulge via low-level ageostrophic confluence. Finally, regions of low Richardson number (arising from strong vertical shears) within the amplifying midtropospheric along-stream ageostrophic thermally-indirect circulation become preferred regions for the development of non-hydrostatic evanescent internal gravity waves. These waves are embedded within the hydrostatic along-stream front above the low-level dryline and are accomapanied by very significant values of vertical momentum flux which act to focus the meso-gamma scale structure of the dryline into smaller scale bulges where low-level winds and vorticities are very high. This meso-gamma scale process follows the hydrostatic tilting and vortex tube stretching which creates meso-beta scale maxima of mid-lower tropospheric vorticity. The turbulent momentum fluxes accompanying wavebreaking within the nonhydrostatic dryline bulge create very large (i.e., stratospheric values of) potential vorticity near 70 kPa due to the nonconservation of potential vorticity on isentropic surfaces.

Notes: Summary The problem of along-stream ageostrophic frontogenesis is studied by employing a numerical model at meso-alpha and meso-beta scales in simulations of the downstream circulations over the Front Range of the Rocky Mountains. Three-dimensional real data simulations at these two scales of motion are used to diagnose the transition from semigeostrophic cross-stream frontogenesis accompanying a propagating baroclinic upper-level jet streak to midtropospheric along-stream ageostrophic frontogenesis. This along-stream ageostrophic frontogenesis results from the perturbation of the jet streak by the Rocky Mountain range. The case study represents an example of internal wave dynamics which are forced by the drag of the Rocky Mountains on a strong jet streak in the presence of a low-level inversion. The simulation results indicate that, unlike semi-geostrophic frontogenesis, a front (which is alligned perpendicular to the axis of the jet stream) may form when significant adiabatic heating occurs within a stratified shear flow over horizontal length scales shorter than the Rossby radius of deformation. The mechanism responsible for the frontogenesis is the growth of the divergent along-stream wind velocity component which becomes coupled to the front's along-stream pressure gradient force. This nonlinear interaction produces hydrostatic mesoscale frontogenesis as follows: 1) vertical wind shear in the along-stream plane strengthens resulting in the increasingly nonuniform vertical variation of horizontal temperature advection as the ageostrophic wind component grows in magnitude downstream of the meso-scale terrain-induced adiabatic heating, 2) increasing along-stream differential vertical motions (i.e., along-stream thermally indirect circulation with warm air sinking to the west and cold air rising to the east) tilt the vertical gradient of isentropes into the horizontal as the vertical temperature gradient increases due to the previous process in proximity to horizontal gradients in the along-stream component of the ageostrophic wind, 3) as tilting motions act to increase the along-stream horizontal temperature gradient, the along-stream confluence acts to nonuniformly increase the along-stream frontal temperature gradient which increases the along-stream pressure gradient force resulting in further accelerations, ageostrophy, and frontal steepening as part of a scale contraction process. The evolution of the aforementioned processes results in the three-dimensional hydrostatic frontogenesis accompanying the overturning of isentropic surfaces. These adjustments act to turn air parcels to the right of the southwesterly geostrophic wind vector at successively lower atmospheric levels as the scale contraction continues. This simulated along-stream front is verified from diagnostic analysis of the profiler-derived temperature and wind fields.

Notes: Abstract Antimitochondrial antibodies (AMA) may be detected in 95% of patients with primary biliary cirrhosis (PBC). The target autoantigens for the AMA were recently identified as four closely related metabolic enzymes located in the mitochondria. We have purified the pyruvate dehydrogenase (PDH) enzyme from bovine heart, showing that all PBC sera reacted with a 74-kd band. PDH was utilized to establish an ELISA assay for detecting the relevant antibodies. One hundred twelve of 120 sera from patients with PBC (95%) reacted with the PDH but none of the 201 control sera, including normal subjects and a panel of sera from other patients with liver diseases, showed similar reactivity. In 77% of the PBC sera the anti-PDH antibody isotype was identified as a combination of IgG and IgM, while in 18% only IgM was detected. In 5% of the sera the isotype was confined to IgG. PBC sera specifically inhibited the PDH enzyme activity. The enzyme inhibition correlated with the anti-PDH antibody titers. Thus, PDH seems to be one of the major target epitopes for AMA observed in sera of patients with PBC.