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Yeast Sfh5 is an unusual member of the Sec14-like phosphatidylinositol transfer protein (PITP) family. Whereas PITPs are defined by their abilities to transfer phosphatidylinositol between membranes in vitro, and to stimulate phosphoinositide signaling in vivo, Sfh5 does not exhibit these activities. Rather, Sfh5 is a redox-active penta-coordinate high spin FeIIIhemoprotein with an unusual heme-binding arrangement that involves a co-axial tyrosine/histidine coordination strategy and a complex electronic structure connecting the open shell irond-orbitals with three aromatic ring systems. That Sfh5 is not a PITP is supported by demonstrations that heme is not a readily exchangeable ligand, and that phosphatidylinositol-exchange activity is resuscitated in heme binding-deficient Sfh5 mutants. The collective data identify Sfh5 as the prototype of a new class of fungal hemoproteins, and emphasize the versatility of the Sec14-fold as scaffold for translating the binding of chemically distinct ligands to the control of diverse sets of cellular activities.

Yeast Sfh5 is an unusual member of the Sec14-like phosphatidylinositol transfer protein (PITP) family. Whereas PITPs are defined by their abilities to transfer phosphatidylinositol between membranes in vitro, and to stimulate phosphoinositide signaling in vivo, Sfh5 does not exhibit these activities. Rather, Sfh5 is a redox-active penta-coordinate high spin FeIIIheme-binding protein with an unusual heme-binding arrangement that involves a co-axial tyrosine/histidine coordination strategy and a complex electronic structure connecting the open shell irond-orbitals with three aromatic ring systems. That Sfh5 is not a PITP is supported by demonstrations that heme is not a readily exchangeable ligand, and that phosphatidylinositol-exchange activity is resuscitated in heme binding-deficient Sfh5 mutants. The collective data identify Sfh5 as the prototype of a new class of fungal hemoproteins, and emphasize the versatility of the Sec14-fold as scaffold for translating the binding of chemically distinct ligands to the control of diverse sets of cellular activities.

We present an investigation of isostructural complexes that feature unsupported direct bonds between a formally trivalent lanthanide ion (Dy3+ ) and either a first-row (Fe) or a second-row (Ru) transition metal (TM) ion. The sterically rigid, yet not too bulky ligand PyCp22- (PyCp22- =[2,6-(CH2 C5 H3 )2 C5 H3 N]2- ) facilitates the isolation and characterization of PyCp2 Dy-FeCp(CO)2 (1; d(Dy-Fe)=2.884(2) A) and PyCp2 Dy-RuCp(CO)2 (2; d(Dy-Ru)=2.9508(5) A). Computational and spectroscopic studies suggest strong TM→Dy bonding interactions. Both complexes exhibit field-induced slow magnetic relaxation with effectively identical energy barriers to magnetization reversal. However, in going from Dy-Fe to Dy-Ru bonding, we observed faster magnetic relaxation at a given temperature and larger direct and Raman coefficients, which could be due to differences in the bonding and/or spin-phonon coupling contributions to magnetic relaxation.

Mrs3 and Mrs4 are mitochondrial inner membrane proteins that deliver an unidentified cytosolic iron species into the matrix for use in iron-sulfur cluster (ISC) and heme biosynthesis. The Mrs3/4 double-deletion strain (ΔΔ) grew slowly in iron-deficient glycerol/ethanol medium but recovered to wild-type (WT) rates in iron-sufficient medium. ΔΔ cells grown under both iron-deficient and iron-sufficient respiring conditions acquired large amounts of iron relative to WT cells, indicating iron homeostatic dysregulation regardless of nutrient iron status. Biophysical spectroscopy (including Mössbauer, electron paramagnetic resonance, and electronic absorption) and bioanalytical methods (liquid chromatography with online inductively coupled plasma mass spectrometry detection) were used to characterize these phenotypes. Anaerobically isolated mitochondria contained a labile iron pool composed of a nonheme high-spin Fe(II) complex with primarily O and N donor ligands, called Fe(580). Fe(580) likely serves as feedstock for ISC and heme biosynthesis. Mitochondria from respiring ΔΔ cells grown under iron-deficient conditions were devoid of Fe(580), ISCs, and hemes; most iron was present as Fe(III) nanoparticles. O(2) likely penetrates the matrix of slow-growing poorly respiring iron-deficient ΔΔ cells and reacts with Fe(580) to form nanoparticles, thereby inhibiting ISC and heme biosynthesis. Mitochondria from iron-sufficient ΔΔ cells contained ISCs, hemes, and Fe(580) at concentrations comparable to those of WT mitochondria. The matrix of these mutant cells was probably sufficiently anaerobic to protect Fe(580) from degradation by O(2). An ~1100 Da manganese complex, an ~1200 Da zinc complex, and an ~5000 Da copper species were also present in ΔΔ and WT mitochondrial flow-through solutions. No lower-mass copper complex was evident.

The syntheses, structural, and magnetic characterization of three new organometallic Ce complexes stabilized by PyCp22- (PyCp22- = [2,6-(CH2C5H3)2C5H3N]2-) are reported. Complex 1 provides the first example of a crystallographically characterized unsupported Ce-Fe bond in a molecular compound. Results from IR spectroscopy and computational analyses suggest weaker Fe → Ce electron-donation than in a previously reported Dy-Fe bonded species.

The syntheses, interconversions, and spectroscopic properties of a set of iron carbonyl clusters containing an interstitial carbide are reported. This includes the low temperature X-ray structures of the six-iron clusters (Y)(2)[Fe(6)(μ(6)-C)(μ(2)-CO)(4)(CO)(12)] (1a−c; where Y = NMe(4), NEt(4), PPh(4)); the five-iron cluster [Fe(5)(μ(5)-C)(CO)(15)] (3); and the novel formulation of the five-iron cluster (NMe(4))(2)[Fe(5)(μ(5)-C)(μ(2)-CO)(CO)(13)] (4). Also included in this set is the novel charge-neutral cluster, [Fe(6)(μ(6)-C)(CO)(18)] (2), for which we were unable to obtain a crystallographic structure. As synthetic proof for the identity of 2, we performed a closed loop of interconversions within a family of crystallographically defined species (1, 3, and 4): [Fe(6)](2−) → [Fe(6)](0) → [Fe(5)](0) → [Fe(5)](2−) → [Fe(6)](2−). The structural, spectroscopic, and electronic properties of this “missing link” cluster 2 were investigated by IR, Raman, XPS, and Mössbauer spectroscopies–as well as by DFT calculations. A single ν(CO) feature (1965 cm(−1)) in the IR spectrum of 2, as well as a prominent Raman feature (ν(symm) = 1550 cm(−1)), are consistent with the presence of terminal carbonyls and a {(μ(6)-C)Fe(6)} arrangement of iron centers around the central carbide. The XPS of 2 exhibits a higher energy Fe 2p(3/2) feature (707.4 eV) as compared to that of 1 (705.5 eV), consistent with the two-electron oxidation induced by treatment of 1 with two equivalents of [Fc](PF(6)) under CO atmosphere (for the two added CO ligands). DFT calculations indicate two axial and four equatorial Fe sites in 1, all of which have the same or similar oxidation states, for example, two Fe(0) and four Fe(+0.5). These assignments are supported by Mössbauer spectra for 1, which exhibit two closely spaced quadrupole doublets with δ = 0.076 and 0.064 mm s(−1). The high-field Mössbauer spectrum of 2 (4.2 K) exhibits three prominent quadrupole doublets with δ = −0.18, −0.11, and +0.41 mm s(−1). This indicates three pairs of chemically equivalent Fe sites. The first two pairs arise from irons of a similar oxidation state, while the last pair arises from irons in a different oxidation state, indicating a mixed-valent cluster. Variable field Mössbauer spectra for 2 were simulated assuming these two groups and a diamagnetic ground state. Taken together, the Mössbauer results and DFT calculations for 2 indicate two axial Fe(II) sites and four equatorial sites of lower valence, probably Fe(0). In the DFT optimized pentagonal bipyramidal structure for 2, the Fe(II)−C(carbide) distances are compressed (~1.84 Å), while the Fe(0)−C(carbide) distances are elongated (~2.05 Å). Analysis of the formulations for 1 (closo-square bipyramid) and 2 (nido-pentagonal bipyramid) is considered in the context of the textbook electron-counting rules of 14n+2 and 14n+4 for closo and nido clusters, respectively. This redox-dependent intracluster disproportionation of Fe oxidation states is concluded to arise from changes in bonding to the central carbide. A similar phenomenon may be promoted by the central carbide of the FeMoco cluster of nitrogenase, which may in turn stimulate N(2) reduction.

We present an in-depth experimental study of a new class of heterometallic, redox-switchable single-molecule magnets (SMMs)., Single-molecule magnets (SMMs) are considered viable candidates for next-generation data storage and quantum computing. Systems featuring switchability of their magnetization dynamics are particularly interesting with respect to accessing more complex logic gates and device architectures. Here we show that transition metal based redox events can be exploited to enable reversible switchability of slow magnetic relaxation of magnetically anisotropic lanthanide ions. Specifically, we report anionic homoleptic bis-diamidoferrocene complexes of Dy3+ (oblate) and Er3+ (prolate) which can be reversibly oxidized by one electron to yield their respective charge neutral redox partners (Dy: [1]–, 1; Er: [2]–, 2). Importantly, compounds 1 and 2 are thermally stable which allowed for detailed studies of their magnetization dynamics. We show that the Dy3+[1]–/1 system can function as an “on”/“off” or a “slow”/“fast” redox switchable SMM system in the absence or presence of applied dc fields, respectively. The Er3+ based [2]–/2 system features “on”/“off” switchability of SMM properties in the presence of applied fields. Results from electrochemical investigations, UV-vis-NIR spectroscopy, and 57Fe Mössbauer spectroscopy indicate the presence of significant electronic communication between the mixed-valent Fe ions in 1 and 2 in both solution and solid state. This comparative evaluation of redox-switchable magnetization dynamics in low coordinate lanthanide complexes may be used as a potential blueprint toward the development of future switchable magnetic materials.

Iron is critical for virtually all organisms, yet major questions remain regarding the systems-level understanding of iron in whole cells. Here, we obtained Mössbauer and EPR spectra of Escherichia coli cells prepared under different nutrient iron concentrations, carbon sources, growth phases, and O2 concentrations to better understand their global iron content. We investigated WT cells and those lacking Fur, FtnA, Bfr, and Dps proteins. The coarse-grain iron content of exponentially growing cells consisted of iron–sulfur clusters, variable amounts of nonheme high-spin FeII species, and an unassigned residual quadrupole doublet. The iron in stationary-phase cells was dominated by magnetically ordered FeIII ions due to oxyhydroxide nanoparticles. Analysis of cytosolic extracts by size-exclusion chromatography detected by an online inductively coupled plasma mass spectrometer revealed a low-molecular-mass (LMM) FeII pool consisting of two iron complexes with masses of ∼500 (major) and ∼1300 (minor) Da. They appeared to be high-spin FeII species with mostly oxygen donor ligands, perhaps a few nitrogen donors, and probably no sulfur donors. Surprisingly, the iron content of E. coli and its reactivity with O2 were remarkably similar to those of mitochondria. In both cases, a “respiratory shield” composed of membrane-bound iron-rich respiratory complexes may protect the LMM FeII pool from reacting with O2. When exponentially growing cells transition to stationary phase, the shield deactivates as metabolic activity declines. Given the universality of oxidative phosphorylation in aerobic biology, the iron content and respiratory shield in other aerobic prokaryotes might be similar to those of E. coli and mitochondria.

Mössbauer and EPR spectra of fermenting yeast cells before and after cell wall (CW) digestion revealed that CWs accumulated iron as cells transitioned from exponential to post-exponential growth. Most CW iron was mononuclear nonheme high-spin (NHHS) Fe(III), some was diamagnetic and some was superparamagnetic. A significant portion of CW Fe was removable by EDTA. Simulations using an ordinary-differential-equations-based model suggested that cells accumulate Fe as they become metabolically inactive. When dormant Fe-loaded cells were metabolically reactivated in Fe-deficient bathophenanthroline disulfonate (BPS)-treated medium, they grew using Fe that had been mobilized from their CWs AND using trace amounts of Fe in the Fe-deficient medium. When grown in Fe-deficient medium, Fe-starved cells contained the lowest cellular Fe concentrations reported for a eukaryotic cell. During metabolic reactivation of Fe-loaded dormant cells, Fe(III) ions in the CWs of these cells were mobilized by reduction to Fe(II), followed by release from the CW and reimport into the cell. BPS short-circuited this process by chelating mobilized and released Fe(II) ions before reimport; the resulting Fe(II)(BPS)3 complex adsorbed on the cell surface. NHHS Fe(II) ions appeared transiently during mobilization, suggesting that these ions were intermediates in this process. In the presence of chelators and at high pH, metabolically inactive cells leached CW Fe; this phenomenon probably differs from metabolic mobilization. The iron regulon, as reported by Fet3p levels, was not expressed during post-exponential conditions; Fet3p was maximally expressed in exponentially growing cells. Decreased expression of the iron regulon and metabolic decline combine to promote CW Fe accumulation.

An ordinary differential equation-based mathematical model was developed to describe trafficking and regulation of iron in growing fermenting budding yeast. Accordingly, environmental iron enters the cytosol and moves into mitochondria and vacuoles. Dilution caused by increasing cell volume is included. Four sites are regulated, including those in which iron is imported into the cytosol, mitochondria, and vacuoles, and the site at which vacuolar Fe(II) is oxidized to Fe(III). The objective of this study was to determine whether cytosolic iron (Fecyt) and/or a putative sulfur-based product of iron-sulfur cluster (ISC) activity was/were being sensed in regulation. The model assumes that the matrix of healthy mitochondria is anaerobic, and that in ISC mutants, O2 diffuses into the matrix where it reacts with nonheme high spin Fe(II) ions, oxidizing them to nanoparticles and generating reactive oxygen species. This reactivity causes a further decline in ISC/heme biosynthesis, which ultimately gives rise to the diseased state. The ordinary differential equations that define this model were numerically integrated, and concentrations of each component were plotted versus the concentration of iron in the growth medium and versus the rate of ISC/heme biosynthesis. Model parameters were optimized by fitting simulations to literature data. The model variant that assumed that both Fecyt and ISC biosynthesis activity were sensed in regulation mimicked observed behavior best. Such "dual sensing" probably arises in real cells because regulation involves assembly of an ISC on a cytosolic protein using Fecyt and a sulfur species generated in mitochondria during ISC biosynthesis and exported into the cytosol.

We studied 28 adolescents/young adults with autism spectrum disorders (ASD) and 13 age/sex matched individuals of typical development (TD). Structured sleep histories, validated questionnaires, actigraphy (four weeks), and salivary cortisol and melatonin (four days each) were collected. Compared to those with TD, adolescents/young adults with ASD had longer sleep latencies and more difficulty going to bed and falling asleep. Morning cortisol, evening cortisol, and the morning-evening difference in cortisol did not differ by diagnosis (ASD vs. TD). Dim light melatonin onsets (DLMOs) averaged across participants were not different for the ASD and TD participants. Average participant scores indicated aspects of poor sleep hygiene in both groups. Insomnia in ASD is multifactorial and not solely related to physiological factors.

The literature has been highly informative for when to use actigraphy and its validity in pediatric research. However, minimal literature exists on how to perform actigraphy, especially in special populations. We determined whether providing actigraphy training to parents and coordinators increased the nights of actigraphy data that could be scored. We compared two studies in children with autism spectrum disorders, one of which provided a basic level of training in a single-site trial and the other of which provided more detailed training to parents and coordinators in a multisite trial. There was an increase in scorable nights in the multisite trial containing a one-hour structured parent training session. Our results support the use of educational tools in clinical trials that use actigraphy.

Cardiac function requires continuous high levels of energy, and so iron, a critical player in mitochondrial respiration, is an important component of the heart. Hearts from 57Fe-enriched mice were evaluated by Mossbauer spectroscopy. Spectra consisted of a sextet and two quadrupole doublets. One doublet was due to residual blood, whereas the other was due to [Fe4S4]2+ clusters and low-spin FeII hemes, most of which were associated with mitochondrial respiration. The sextet was due to ferritin; there was no evidence of hemosiderin, a ferritin decomposition product. Iron from ferritin was nearly absent in young hearts, but increased steadily with age. EPR spectra exhibited signals similar to those of brain, liver, and human cells. No age-dependent EPR trends were apparent. Hearts from HFE-/- mice with hemochromatosis contained slightly more iron overall than controls, including more ferritin and less mitochondrial iron; these differences typify slightly older hearts, perhaps reflecting the burden due to this disease. HFE-/- livers were overloaded with ferritin but had low mitochondrial iron levels. IRP2-/- hearts contained less ferritin than controls but normal levels of mitochondrial iron. Hearts of young mice born to an iron-deficient mother contained normal levels of mitochondrial iron and no ferritin; the heart from the mother contained low ferritin and normal levels of mitochondrial iron. High-spin FeII ions were nearly undetectable in heart samples; these were evident in brains, livers, and human cells. Previous Mossbauer spectra of unenriched diseased human hearts lacked mitochondrial and blood doublets and included hemosiderin features. This suggests degradation of iron-containing species during sample preparation.

Background Umbilical cord blood (UCB) products have traditionally been thawed using a washing method intended to stabilize the cells, reduce dimethyl sulfoxide (DMSO) toxicity, and remove potentially ABO-incompatible red blood cell (RBC) stroma and plasma. Concerns with this approach include loss of total nucleated cells (TNCs), bag breakage during centrifugation, and poor reproducibility by transplant centers unfamiliar with this technique. We rationalized that a simple 1:1 dilution without centrifugation would stabilize the product and reduce the DMSO concentration by 50%, allowing for a controlled thaw in the laboratory without the risks of cell loss. Study design and methods We compared the traditional wash method with albumin reconstitution (dilution) and thaw only (no dilution or wash), assessing measurements of viability, TNC, CD34, and colony-forming cell (CFC) recovery post-thaw. Ten cryopreserved UCB products were thawed, split equally into three parts, and treated using each method. Product stability was measured at multiple time intervals up to 48hours post-thaw. Results Throughout the entire evaluation, traditional wash and dilution methods performed equally well with no significant differences observed in 7-aminoactinomycin viability, TNC, CD34, or CFC recovery. For 163 patients in which diluted products were administered, there were no serious adverse effects at infusion and similar time to engraftment was observed when compared to historical experiences with traditional wash and direct infusion. Conclusion We conclude that removing DMSO, RBC stroma, and plasma post-thaw using a wash method is not necessary when UCB products are RBC and plasma reduced before cryopreservation.

Background: Several epidemiologic studies in the United States and Europe have linked Alternaria sensitivity to both persistence and severity of asthma. In this study, we examined T cell responses and HLA class II alleles in children with mod- erate-severe asthma. Methods: Ninety-six children with moderate-severe asthma were compared to 90 children with mild asthma. HLA class II genotyping was performed to determine HLA allelic frequencies. Th1/Th2 Alternaria-specific T cell cytokine responses were determined by the use of Alternaria-stimulated cultures. HLA class II restriction was examined by inhibition of Alternaria-stimulated lymphoproliferative responses with blocking anti-HLA class II monoclonal antibodies. Results: Children with moderate-severe asthma had significantly increased sensitivi- ties to Aspergillus fumigatus; sensitivities to Alternaria were similar in both moder- ate-severe and mild asthmatics. The frequency of HLA-DRB1*13 alleles were increased in mold-sensitive moderate-severe asthmatic children. HLA-DRB1*03 tended to be increased in mold-sensitive moderate-severe asthmatics. The frequency of HLA-DQB1*03 alleles was significantly decreased in mold and Alternaria-sensi- tive moderate-severe asthma. HLA class II blocking monoclonal antibodies demon- strated HLA-DR restriction. Alternaria-stimulated IL-5 and IL-13 synthesis was significantly increased in moderate-severe asthmatics. IL-5 and IL-13 synthesis was significantly increased in Alternaria-stimulated lymphocyte cultures of HLA- DQB1*03- asthmatics compared to HLA-DQB1*03+ asthmatics. Conclusions: In children with Alternaria-sensitive moderate-severe asthma, there was increased Th2 sensitivity to Alternaria stimulation. This was associated with HLA-DR restriction and with increased frequency of HLA-DRB1*13 and HLA- DRB1*03. There was decreased frequency of HLA-DQB1*03 in Alternaria-sensitive moderate-severe asthma, suggesting HLA-DQB1*03 may be protective of the devel- opment of Alternaria-sensitive severe asthma.

Background: Allergic bronchopulmonary aspergillosis (ABPA) is a bronchial allergic inflammatory reaction to Aspergillus fumigatus that occurs in a minority of susceptible asthmatic and cystic fibrosis (CF) patients. Previous studies identified that HLA-DR2/DR5 was associated with susceptibility to develop ABPA; however, HLA-DR2/DR5 occurs frequently in non-ABPA patients as well.Objective: We hypothesize that in addition to HLA-DR restriction, other genetic risk factors predispose asthmatic and CF patients to develop ABPA. Methods: HLA-DR and interleukin-4 (IL-4) receptor α-chain (IL-4RA), IL-13, and IL-10 -1082 polymorphisms were examined in 41 asthmatic and CF patients with ABPA and in 84 asthmatic and CF non-ABPA patients.Results: HLA-DR2 and/or DR5 were identified in 70.7% of ABPA patients and in 35.7% of non-ABPA patients. IL-4RA single-nucleotide polymorphisms (SNPs) were present in 95% of ABPA patients, with the ile75val SNP in 80.5% of ABPA patients. Both HLA-DR2/DR5 and IL-4RA SNPs individually we...

Omalizumab is a monoclonal antibody that decreases IgE levels and has been shown to decrease asthma exacerbations, emergency care visits, and hospitalizations when added on to standard medical therapy for moderate–severe persistent asthma. We describe the results of omalizumab treatment in children 6 to 18 years old with severe asthma at a single pediatric medical center. This is a retrospective analysis of 27 children, 13 ± 3 years old, with severe asthma evaluated before and after treatment with omalizumab. Their baseline data were compared to 34 children with moderate–severe persistent asthma, 11 ± 3 years old, and to 65 children with mild persistent asthma, 10 ± 3 years old. Medication use, pulmonary function tests, IgE levels, and aeroallergen sensitivity differences were analyzed among moderate to severe asthmatics and mild asthmatics. Pulmonary function tests, quality of life questionnaires, and reduction of inhaled corticosteroid (ICS) doses were evaluated during omalizumab treatment. Children wit...

We previously reported that microinjection of purified Ras protein stimulated DNA synthesis in quiescent Wistar rat thyrocytes and that TSH (TSH)-stimulated DNA synthesis was Ras-dependent. In contrast to these results, microinjection of cellular or oncogenic Ras significantly reduced TSH-stimulated thyroglobulin (Tg) expression, a marker of thyrocyte differentiation. Microinjection of a dominant inhibitory Ras mutant had no effect on TSH-stimulated Tg expression. As the Tg promoter is cAMP-responsive and Ras was previously reported to interfere with entry of catalytic (C) subunit of the cAMP-dependent protein kinase into the nucleus, experiments were performed to assess the effects of Ras on cAMP-mediated signaling. Microinjection of either cellular or oncogenic Ras had no effect on TSH-stimulated entry of C subunit into the nucleus. Consistent with these data, Ras did not reduce TSH-stimulated cAMP response element binding protein phosphorylation, or cAMP response element-regulated gene expression. These results demonstrate that Ras exerts differential effects on TSH signaling; Ras increases TSH-stimulated DNA synthesis and decreases TSH-induced Tg expression. Moreover, the mechanism through which Ras induces Tg expression lies distal to entry of C subunit into the nucleus, cAMP response element binding protein phosphorylation, and cAMP response element-regulated gene expression.

Two coaxial superconducting magnetic coils that carry currents in the same direction and that are simultaneously levitated may serve for antihydrogen plasma confinement. The configuration may be suitable for use by a collaboration at the CERN Antiproton Decelerator facility to test fundamental symmetries between the properties of hydrogen and antihydrogen. Nested Penning traps are currently used to confine recombining antihydrogen plasma. Symmetry studies require the production of sufficiently cold antihydrogen. However, plasma drifts within nested Penning traps can increase the kinetic energy of antiprotons that form antihydrogen atoms. Dual levitated coils may serve to confine relatively large, cold, dense non-drifting recombining antihydrogen plasmas. A minimum-B magnetic field that is produced by the coils could provide for atom trapping. A toroidal plasma is confined between the coils. High density plasmas may be possible, by allowing plasma pressure to balance mechanical pressure to keep the coils apart. Progress is reported on theoretical and experimental efforts. The theoretical effort includes the development of a classical trajectory Monte Carlo simulation of confinement. The experimental effort includes levitation of a NdFeB permanent ring magnet, which produces a magnetic field that is qualitatively similar to the field that would be produced by the two coaxial superconducting magnetic coils. Liquid-nitrogen-cooled Bi-2223 high-temperature-superconducting components, with a critical temperature of 108 K, were used to levitate the ring magnet. An issue concerning keeping the plane of the levitated ring horizontal is discussed.

Several epidemiologic studies in the United States and Europe have linked Alternaria sensitivity to both persistence and severity of asthma. In this study, we examined T cell responses and HLA class II alleles in children with moderate-severe asthma.Ninety-six children with moderate-severe asthma were compared to 90 children with mild asthma. HLA class II genotyping was performed to determine HLA allelic frequencies. Th1/Th2 Alternaria-specific T cell cytokine responses were determined by the use of Alternaria-stimulated cultures. HLA class II restriction was examined by inhibition of Alternaria-stimulated lymphoproliferative responses with blocking anti-HLA class II monoclonal antibodies.Children with moderate-severe asthma had significantly increased sensitivities to Aspergillus fumigatus; sensitivities to Alternaria were similar in both moderate-severe and mild asthmatics. The frequency of HLA-DRB1*13 alleles were increased in mold-sensitive moderate-severe asthmatic children. HLA-DRB1*03 tended to be increased in mold-sensitive moderate-severe asthmatics. The frequency of HLA-DQB1*03 alleles was significantly decreased in mold and Alternaria-sensitive moderate-severe asthma. HLA class II blocking monoclonal antibodies demonstrated HLA-DR restriction. Alternaria-stimulated IL-5 and IL-13 synthesis was significantly increased in moderate-severe asthmatics. IL-5 and IL-13 synthesis was significantly increased in Alternaria-stimulated lymphocyte cultures of HLA-DQB1*03- asthmatics compared to HLA-DQB1*03+ asthmatics.In children with Alternaria-sensitive moderate-severe asthma, there was increased Th2 sensitivity to Alternaria stimulation. This was associated with HLA-DR restriction and with increased frequency of HLA-DRB1*13 and HLA-DRB1*03. There was decreased frequency of HLA-DQB1*03 in Alternaria-sensitive moderate-severe asthma, suggesting HLA-DQB1*03 may be protective of the development of Alternaria-sensitive severe asthma.

Background Asthma afflicts 6% to 8% of the United States population, and severe asthma represents approximately 10% of asthmatic patients. Several epidemiologic studies in the United States and Europe have linked Alternaria sensitivity to both persistence and severity of asthma. In order to begin to understand genetic risk factors underlying Alternaria sensitivity and asthma, in these studies we examined T cell responses to Alternaria antigens, HLA Class II restriction and HLA-DQ protection in children with severe asthma. Methods Sixty children with Alternaria-sensitive moderate-severe asthma were compared to 49 children with Alternaria-sensitive mild asthma. We examined HLA-DR and HLA-DQ frequencies in Alternaria-sensitive asthmatic by HLA typing. To determine ratios of Th1/Th2 Alternaria-specific T-cells, cultures were stimulated in media alone, Alternaria alternata extract and Alt a1. Sensitivity to IL-4 stimulation was measured by up-regulation of CD23 on B cells. Results Children with Alternaria-sensitive moderate-severe asthma trended to have increased sensitivities to Cladosporium (46% versus 35%), to Aspergillus (43% versus 28%), and significantly increased sensitivities to trees (78% versus 57%) and to weeds (68% versus 48%). The IL-4RA ile75val polymorphism was significantly increased in Alternaria-sensitive moderate-severe asthmatics, 83% (0.627 allele frequency) compared to Alternaria-sensitive mild asthmatics, 57% (0.388 allele frequency). This was associated with increased sensitivity to IL-4 stimulation measured by significantly increased IL-4 stimulated CD23 expression on CD19+ and CD86+CD19+ B cells of Alternaria-sensitive moderate-severe asthmatics. IL-5 and IL-13 synthesis was significantly increased in Alternaria-sensitive moderate-severe asthmatics compared to mild asthmatics to Alternaria extract and Alt a1 stimulation. The frequency of HLA-DQB1*03 allele was significantly decreased in Alternaria-sensitive moderate-severe asthmatics compared to mild asthmatics, 39% versus 63%, with significantly decreased allele frequency, 0.220 versus 0.398. Summary In children with Alternaria-sensitive moderate severe asthma, there was an increased Th2 response to Alternaria stimulation and increased sensitivity to IL-4 stimulation. This skewing towards a Th2 response was associated with an increased frequency of the IL-4RA ile75val polymorphism. In evaluating the HLA association, there was a decreased frequency of HLA-DQB1*03 in Alternaria-sensitive moderate severe asthmatic children consistent with previous studies suggest that HLA-DQB1*03 may be protective against the development of mold-sensitive severe asthma.

BACKGROUND: Cord blood (CB) viability determines product quality and varies with time and temperature of exposure before cryopreservation. Global viability assessment may not reflect viability of white blood cell (WBC) subsets, CD34+ cell viability, or hematopoietic stem/progenitor cells function. STUDY DESIGN AND METHODS: We compared trypan blue (TB) and acridine orange/propidium iodide (AO/PI) staining with flow-cytometric (7-aminoactinomycin D [7-AAD]) viability in total WBCs (Tot-AAD), granulocytes, monocytes, lymphocytes, and CD34+ cells and total nucleated cell, CD34+, and colony-forming cell (CFC) recovery as a function of time and temperature (4, 24, and 37 degrees C) before cryopreservation. RESULTS: TB, AO/PI, and Tot-AAD viability was concordant up to 72 hours (4 degrees C) and 48 hours (24 degrees C) postcollection; however, CD34+ viability was significantly higher due to loss of viable granulocytes. In contrast, at "physiologic" temperature (37 degrees C), the decline in TB, AO/PI, and Tot-AAD viability was significantly lower than the rate of viable CD34+ and CFC loss. At all times and temperatures, CFC recovery correlated best with CD34+ viability and recovery. CONCLUSIONS: CB cell populations exhibit differential time- and temperature-dependent susceptibility to in vitro cell death; consequently, global viability measurements using TB, AO/PI, or 7-AAD (Tot-AAD) significantly underestimate (4-24 degrees C) or overestimate (24-37 degrees C) CD34+ viability and CFC recovery. Our results demonstrate the limitations of global viability assessment with TB, AO/PI, and total AAD; endorse the routine use of CD34+ cell viability measurements; emphasize the importance of temperature control during shipment; and have implications with regard to establishing acceptable "cutoff" values for viability measurements and CB collection through processing time.

The present study examined the efficacy of the New York University visual scanning training program in treating patients with left-sided hemi-inattention and homonymous hemianoptic problems resulting from right hemispheric cortical lesions secondary to middle cerebral artery strokes. The study examined changes on a visual scanning task as well as generalization of training to obstacle course performances requiring the subjects to navigate their wheelchairs through a runway lined with chairs. Three male subjects were trained on the scanner in a stationary position and while they moved their wheelchairs. Progress was assessed using a multiple baseline across subjects design. Results revealed that all subjects showed systematic changes on the scanner task. Generalization of training to the obstacle course was more variable with one subject showing considerably fewer errors and the other subjects showing less impressive improvements in performance. A 1-year follow-up suggested that the scanning skill was maintained in all subjects. The need for adequate task analysis and training procedures which include all relevant cognitive/behavioral skills is discussed. In addition, the authors discuss the problems of attaining an adequate pretraining assessment of the brain-impaired subjects' behavioral/cognitive repertoire.

A procedure for predicting the oxygen transmission rates of multilayer packaging materials containing water sensitive layers under humid conditions has been vali dated by derivation of the equation used and comparison of predicted rates with measured rates on a specially prepared multilayer material. A computer program which aids in making the required calculations is included. Excellent agreement between predicted and measured rates was obtained.

The initial experiment of this paper investigated the role of hemispatial neglect in wheelchair-related accidents of right-hemisphere stroke victims. Twelve subjects with and 12 subjects without neglect of left space drove their wheelchairs through an obstacle course. Two types of obstacle course errors were evaluated: direct hits and sideswipes. The neglecting group made significantly more direct hits but there were no significant differences between groups in sideswipe errors. In Experiment 2, the nonneglecting group's data were compared with a left-hemisphere stroke group without neglect and three motor control groups to investigate if their errors resulted from motor deficits. The right-hemisphere stroke group made significantly more left-sided errors and errors in contralateral space than any other group. In Experiment 3, 13 subjects with neglect were taught to scan to the left which resulted in significant decreases in direct hits but not in sideswipes on the obstacle course. These results suggest that obstacle course performance is sensitive to more than hemispatial neglect.

Edwardsiella tarda, a member of the family Enterobacteriaceae, has recently become recognized as pathogenic, especially in patients with an underlying illness. In the present report, a patient had sickle cell hemoglobinopathy and E tarda bacteremia. Other cases of serious infection with Edwardsiella are reported in the literature. Edwardsiella infection may present as bacteremia, enteric fever, gastroenteritis, localized infection, and an asymptomatic carrier state. On the basis of this review, bacteremia with E tarda often has been associated with septic shock and has a high mortality, but this may be related to the usual presence of a serious underlying illness in these patients.

Excerpt The reported incidence of typhoid fever has diminished greatly in the last 20 years. With public health education, accurate methods of diagnosis and the presence of efficacious antimicrobia...

RESERPINE has become increasingly popular in a wide variety of clinical conditions since its isolation in 1952.1 The hypotensive and bradycardic action is useful in the treatment of hypertension.2 ...

• Edwardsiella tarda , a member of the family Enterobacteriaceae, has recently become recognized as pathogenic, especially in patients with an underlying illness. In the present report, a patient had sickle cell hemoglobinopathy and E tarda bacteremia. Other cases of serious infection with Edwardsiella are reported in the literature. Edwardsiella infection may present as bacteremia, enteric fever, gastroenteritis, localized infection, and an asymptomatic carrier state. On the basis of this review, bacteremia with E tarda often has been associated with septic shock and has a high mortality, but this may be related to the usual presence of a serious underlying illness in these patients. ( Arch Intern Med 1989;149:208-210)