T-follicular helper (Tfh) cells differentiate through a multistep process, culminating in germinal center (GC) localized GC-Tfh cells that provide support to GC-B cells. T-follicular regulatory (Tfr) cells have critical roles in the control of Tfh cells and GC formation. Although Tfh-cell differentiation is inhibited by IL-2, regulatory T (Treg) cell differentiation and survival depend on it. Here, we describe a CD25− subpopulation within both murine and human PD1+CXCR5+Foxp3+ Tfr cells. It is preferentially located in the GC and can be clearly differentiated from CD25+ non–GC-Tfr, Tfh, and effector Treg (eTreg) cells by the expression of a wide range of molecules. In comparison to CD25+ Tfr and eTreg cells, CD25− Tfr cells partially down-regulate IL-2–dependent canonical Treg features, but retain suppressive function, while simultaneously up-regulating genes associated with Tfh and GC-Tfh cells. We suggest that, similar to Tfh cells, Tfr cells follow a differentiation pathway generating a mature GC-localized subpopulation, CD25− Tfr cells.

Electron correlations are known to play an important role in determining the unusual physical properties of a variety of compounds. Such properties include high-temperature superconductivity, heavy fermion behaviour and metal-to-insulator transitions. High-resolution photoelectron spectroscopy (PES) provides a means of directly probing the electronic states (particularly those near the Fermi level) in these materials, but the short photoelectron mean free paths (< or = 5 A) associated with the low excitation energies conventionally used (< or = 120 eV) make this a surface-sensitive technique. Now that high-resolution PES is possible at much higher energies, with mean free paths as long as 15 A (ref. 6), it should become feasible to probe the bulk electronic states in these materials. Here we demonstrate the power of this technique by applying it to the cerium compounds CeRu2Si2 and CeRu2. Previous PES studies of these compounds revealed very similar spectra for the Ce 4f electronic states, yet it is expected that such states should be different owing to their differing degrees of hybridization with other valence bands. Our determination of the bulk Ce 4f electronic states of these compounds resolves these differences.

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The microbiota-gut-brain axis transmits bidirectional communication between the gut and the central nervous system and links the emotional and cognitive centers of the brain with peripheral gut functions. This communication occurs along the axis via local, paracrine, and endocrine mechanisms involving a variety of gut-derived peptide/amine produced by enteroendocrine cells. Neural networks, such as the enteric nervous system, and the central nervous system, including the autonomic nervous system, also transmit information through the microbiota-gut-brain axis. Recent advances in research have described the importance of the gut microbiota in influencing normal physiology and contributing to disease. We are only beginning to understand this bidirectional communication system. In this review, we summarize the available data supporting the existence of these interactions, highlighting data related to the contribution of enteroendocrine cells and the enteric nervous system as an interface between the gut microbiota and brain.

The first observation of //-mode confinement with electron cyclotron heating as the sole auxiliary heating method has been made in divertor discharges in the DIII-D tokamak. These discharges exhibit the usual characteristics of the H mode, including improved confinement of particles and energy, when electron cyclotron heating is added at a power level above 0.7 MW. The //-mode transition is accompanied by the development of an electron temperature pedestal of 0.25 keV and a dramatic steepening of the density gradient near the separatrix.PACS numbers: 52.55.Fa, 52.50.GjThe plasma energy-confinement time in tokamaks has generally been found to decrease when auxiliary power is added to the Ohmic heating. This phenomenon, L-mode scaling,' makes it difficult to heat a tokamak plasma to reactor temperatures. However, a regime of improved confinement, ^-mode scaling, has been observed in several tokamaks with neutral-beam injection (NBI) heating. ^"^ In the H mode, the energy confinement time may remain at the Ohmic level without degradation when auxiliary power is added, or the confinement time may degrade with power but remain a factor of about 2 larger than the confinement time under the L-mode scaling, as in the JET tokamak.^ Recently, the H mode has also been obtained with ion cyclotron heating,^ and, in the JFT-2M tokamak, with ion cyclotron heating,^ with a combination of NBI and electron cyclotron heating (ECH),^^ and with NBI in limiter discharges. ^^ The present work reports the first observation of the H mode with electron cyclotron heating as the sole source of auxiliary heating.These experiments have been carried out in the DIII-D tokamak operated in the expanded boundary divertor configuration under conditions which have facilitated the //-mode transition in discharges heated by NBI.^'^^ Typical plasmas had Ro = \.6S m, a-0.62 m, elongation = 1.8, with a single null divertor located in the direction of the ion \B drift, as preferred for the H mode. ^^ The gap between the separatrix flux surface and the nearest material wall was typically 3.5 cm. The plasma was developed from deuterium gas, and the plasma current was 0.48 MA.The ECH power was applied at a frequency of 60 GHz, for which the second-harmonic resonance occurs at a local magnetic field of 1.07 T. The antennas were located near the outside midplane of the plasma, and launched 85% of the incident power in the extraordinary mode and 15% in the ordinary mode. The total incident power, after allowance for waveguide losses, was up to 0.9 MW. The antennas launch power in the HEn mode at an angle ±17° to the radial with a Gaussian dispersion 11 ° in half width. When the resonance is at the plasma center, for the 17° launch angle, the local cutoff density for the extraordinary mode is 1.86x10^^ m"^, and for densities well below cutoff", the power is deposited in a volume with approximate minor radius of 20 cm in the midplane. The ECH power was typically a factor of 8 larger than the Ohmic power during the heating, and so the plasma power balance was domi...

We conducted a structural analysis of the cell wall mannans isolated from two Candida tropicalis strains, IFO 0199 and IFO 1647, exhibiting strong agglutinabilities against anti-Candida factor sera 5 and 6. The products released from these mannans by acid treatment were identified as the oligosaccharides, from biose to pentaose, consisting solely of "-1,2-linked mannopyranose units corresponding to common epitopes of Candida albicans serotypes A and B (factor 5). Mild acetolysis of acidand alkali-treated mannans produced large amounts of hexaose and heptaose, Manp1l-2Manpl-1anpotlol-2Manpol-2Manpal-2Man and Manpol-2Manpfrl-2Manpjl-2Manpal-2Manpft1-2Manppal-2Man, corresponding to the C. albicans serotype A-specific epitopes (factor 6). However, the homologous pentaose, Manpjl-2Manpal-2Manpal-2Manpyal-2Man, was not generated by this procedure. The oligosaccharides (biose to hexaose) obtained from the mannans by conventional acetolysis were composed exclusively of a-1,2-linked mannopyranose units. Therefore, the mannans of C. tropicalis IFO 0199 and IFO 1647 do not have the a-1,3-linked mannopyranose units previously observed in the mannans of C. albicans and Candida stelatoidea. The results of this study and previous findings indicate that the similarity of the antigenicities of three Candida species, C. albicans serotype A, C. steUatoidea type II, and C. tropicalis, reside in the 0-1,2 and ot-1,2 linkages containing oligomannosyl side chain (factor 6) in the cell wall mannan.

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