[Relationship between frailty and functional status in lung transplant candidates]. / Relación entre la fragilidad y la capacidad funcional en los pacientes candidatos a trasplante de pulmón.

INTRODUCTION: Lung transplant (LT) is one of the therapeutic options for patients with terminal respiratory diseases. It is highly important to incorporate the functional status and frailty assessment into the selection process of candidates for LT. OBJECTIVES: Identify the prevalence of frailty in the LT waiting list. Study the relationship between frailty, functional status, Lung Allocation Score (LAS) and muscular dysfunction. METHODOLOGY: Descriptive transversal study of patients on the waiting list for LT. POPULATION: 74 patients with chronic respiratory diseases assessed by the lung transplant committee and accepted to be transplanted in a university hospital in Barcelona. The outcome variables were frailty status was evaluate for SPPB test, functional capacity was evaluate for the six-minute walking test (6MWT) and muscular dysfunction. The results were analyzed with the statistical package STATA 12. RESULTS: Sample of 48 men and 26 women, with a median age of 56.55 years (SD 10.87. The prevalence of frailty assessed with the SPPB was 33.8% (8.1% are in frailty and 25.7% are in a state of pre-frailty). There is a relationship between the SPPB, 6MWT and maximal inspiratory pressure, but not with others force values. There is a relationship between the risk of frailty (scores below 9 in SPPB) and the meters walked in 6 but not with the LAS. CONCLUSIONS: The risk of frailty in patients with terminal chronic respiratory diseases is high. Frailty is related with functional capacity, but not with LAS.

Compressibility and Structural Transformations of Aluminogermanate Imogolite Nanotubes under Hydrostatic Pressure.

We present in situ pressure experiments on aluminogermanate nanotubes studied by X-ray scattering and absorption spectroscopy measurements. Structural transformations under hydrostatic pressure below 10 GPa are investigated as a function of the morphology, organization, or functionalization of the nanotubes. Radial deformations, ovalization for isolated nanotubes, and hexagonalization when they are bundled are evidenced. Radial collapse of single-walled nanotubes is shown to occur, in contrast to the double-walled nanotubes. The effect of the transmitting pressure medium used on the collapse onset pressure value is demonstrated. Axial Young's moduli are determined for isolated (400 GPa) and bundled (600 GPa) single-walled nanotubes, double-walled nanotubes (440 GPa), and methylated single-walled nanotubes (200 GPa).

[Spanish validation of the Autonomic Standards Assessment Form in spinal cord injuries]. / Validación española del cuestionario Autonomic Standards Assessment Form en la lesión medular.

INTRODUCTION AND OBJECTIVES: Autonomic nervous system (ANS) dysfunction in patients with spinal cord injury (SCI) severely impacts morbidity and mortality. However, research initiatives aiming to gain insight into the direct impact of ANS dysfunction on health outcomes in persons with SCI are still lacking. Thus, this study had 2main objectives: 1) to translate into Spanish the revised edition of the International Standards on documentation of remaining Autonomic Function after SCI (ISAFSCI), and 2) to describe the impact of ANS dysfunction in a sample of SCI patients. MATERIAL AND METHODS: Cross-sectional observational pilot study in 51 traumatic SCI patients (> 1 year after injury). Demographic, medical and ISAFSCI data were studied. RESULTS: The Spanish version of the ISAFSCI showed that the most altered systems in the sample were sweating control (above-lesion hyperhidrosis in 33.3%; below-lesion hyperhidrosis in 17.6%; below-lesion hypohidrosis in 21.6%) and temperature control (hyperthermia in 76.5%). In addition, 74.5% of the sample had complete loss of control of the lower urinary tract, and 82.4% had no control of the bowel. Finally, genital arousal was reflex in 47.1% and orgasm and ejaculation were reduced or altered in most of the patients (92.2% and 84.3%, respectively). CONCLUSION: The Spanish version of the ISAFSCI is a useful and practical tool, and can be employed in clinical practice to assess ANS function in patients with SCI. Understanding the role of ANS in persons with SCI is crucial to improve their health status and reduce secondary complications post-SCI, and consequently help to improve the clinical management in these individuals.

Validación española del cuestionario Autonomic Standards Assessment Form en la lesión medular / Spanish validation of the Autonomic Standards Assessment Form in spinal cord injuries

Introducción y objetivos: Las disfunciones del sistema nervioso autónomo (SNA) en pacientes con lesión medular (LM) impactan de forma severa su morbimortalidad. Sin embargo, siguen siendo escasas las iniciativas de investigación destinadas a conocer dicha patología. Por ello, este artículo tiene como objetivos: 1) traducir al español el documento International Standards on documentation of remaining Autonomic Function after SCI (ISAFSCI), y 2) describir la influencia de la alteración del SNA en una muestra de pacientes con LM. Material y métodos: Estudio piloto observacional de tipo transversal, en 51 pacientes con LM traumática (> 1 año de evolución). Se recogiero datos sociodemográficos, médicos, ISAFSCI. Resultados: La versión española del ISAFSCI mostró que los sistemas más alterados fueron el control de la sudoración (hiperhidrosis supralesional 33,3%, hiperhidrosis infralesional 17,6%, hipohidrosis infralesional 21,6%) y de la temperatura (hipertermia 76,5%). El 74,5% tenía ausencia completa de control urinario inferior y el 82,4% no tenía control del intestino. La excitación genital fue refleja en el 47,1% de la muestra y el orgasmo y la eyaculación estaban alterados o reducidos en la mayoría de los casos (92,2% y 84,3%, respectivamente). Conclusiones: La versión española del ISAFSCI es una herramienta práctica y de gran utilidad en contextos clínicos para la evaluación de la función del SNA en personas con una LM. Entender el papel del SNA en personas con una LM es crucial para mejorar su estado de salud general y reducir complicaciones secundarias derivadas de la LM, y consecuentemente contribuye a un mejor manejo clínico

Introduction and objectives: Autonomic nervous system (ANS) dysfunction in patients with spinal cord injury (SCI) severely impacts morbidity and mortality. However, research initiatives aiming to gain insight into the direct impact of ANS dysfunction on health outcomes in persons with SCI are still lacking. Thus, this study had 2main objectives: 1) to translate into Spanish the revised edition of the International Standards on documentation of remaining Autonomic Function after SCI (ISAFSCI), and 2) to describe the impact of ANS dysfunction in a sample of SCI patients. Material and methods: Cross-sectional observational pilot study in 51 traumatic SCI patients (> 1 year after injury). Demographic, medical and ISAFSCI data were studied. Results: The Spanish version of the ISAFSCI showed that the most altered systems in the sample were sweating control (above-lesion hyperhidrosis in 33.3%; below-lesion hyperhidrosis in 17.6%; below-lesion hypohidrosis in 21.6%) and temperature control (hyperthermia in 76.5%). In addition, 74.5% of the sample had complete loss of control of the lower urinary tract, and 82.4% had no control of the bowel. Finally, genital arousal was reflex in 47.1% and orgasm and ejaculation were reduced or altered in most of the patients (92.2% and 84.3%, respectively). Conclusion: The Spanish version of the ISAFSCI is a useful and practical tool, and can be employed in clinical practice to assess ANS function in patients with SCI. Understanding the role of ANS in persons with SCI is crucial to improve their health status and reduce secondary complications post-SCI, and consequently help to improve the clinical management in these individuals

Graphene oxide-carbon nanotube hybrid assemblies: cooperatively strengthened OH···O[double bond, length as m-dash]C hydrogen bonds and the removal of chemisorbed water.

Owing to their great significance for energy storage and sensing applications, multi-layer papers consisting of graphene oxide-carbon nanotube (GO-CNT) hybrid sheets were prepared by in situ exfoliation of graphite oxide in the presence of oxidized CNTs (oCNTs). For the first time we elucidate the influence of oCNTs on chemisorbed water (CW), i.e. the water molecules inherently bound to the oxygen functional groups (OFGs) of graphene oxide (GO) and responsible for irreversible structural damage upon thermal reduction processes. We show that oCNTs self-assemble onto GO sheets during the liquid phase processing steps by forming cooperatively strengthened OH···O[double bond, length as m-dash]C hydrogen bonds between the carboxylic groups of the oCNTs and OFGs of GO. At oCNT amounts of about 10 to 15 wt% this leads to the displacement of considerable amounts of CW without altering the original chemical composition of GO. The thermally reduced GO-CNT (rGO-CNT) papers reveal improved sp2 character and an enhancement of the specific capacitance by 75% with respect to thermally reduced GO (rGO), largely due to the effective removal of CW by oxidized CNTs. These findings disclose the relevance of the cooperative hydrogen bonding phenomena in graphene oxide paper/film electrodes for the development of improved electrochemical energy storage and sensing devices.

Intralesional regulatory T-cell suppressive function during human acute and chronic cutaneous leishmaniasis due to Leishmania guyanensis.

The levels of regulatory T cells (Treg cells), analyzed by Foxp3 mRNA expression, were determined in lesions from patients with acute cutaneous leishmaniasis (ACL) and chronic cutaneous leishmaniasis (CCL). We demonstrated that Treg cells preferentially accumulate in lesions from ACL patients during the early phase of infection (lesion duration of less than 1 month). In addition, levels of Foxp3 mRNA transcripts were significantly higher in specimens from patients with CCL than in those from patients with ACL, suggesting a critical role of intralesional Treg cells in CCL. Intralesional Treg cells from both ACL and CCL patients were shown to have suppressive functions in vitro, since they inhibited the gamma interferon (IFN-gamma) produced by CD4(+) CD25(-) T cells purified from peripheral blood mononuclear cells from the same patient in response to Leishmania guyanensis stimulation. Intralesional 2,3-indoleamine dioxygenase (IDO) mRNA expression was associated with that of Foxp3, suggesting a role for IDO in the suppressive activity of intralesional Treg cells. In addition, a role, albeit minor, of interleukin-10 (IL-10) was also demonstrated, since neutralization of IL-10 produced by intralesional T cells increased IFN-gamma production by effector cells in an in vitro suppressive assay. These results confirm the role of intralesional Treg cells in the immunopathogenesis of human Leishmania infection, particularly in CCL patients.

How confinement affects the dynamics of c60 in carbon nanopeapods.

The dynamics of confined systems is of major concern for both fundamental physics and applications. In this Letter, the dynamics of C60 fullerene molecules inside single walled carbon nanotubes is studied using inelastic neutron scattering. We identify the C60 vibrations and highlight their sensitivity to temperature. Moreover, a clear signature of rotational diffusion of the C60 is evidenced, which persists at lower temperature than in 3D bulk C60. It is discussed in terms of confinement and of reduced dimensionality of the C60 chain.

Shape-controlled platinum nanocubes and their assembly into two-dimensional and three-dimensional superlattices.

Liquid-liquid phase transfer has been used to synthesize platinum nanocrystals with a cubic morphology. By finely tuning the parameters controlling the nucleation and growth processes, nanometric truncated cubes or perfect cubes may be obtained. To our knowledge, this is the first time such shapes are obtained with this procedure. The importance of both the length of the capping agent to control the growth process and the bromide anions as poison for the (111) facet is shown. The low degree of size polydispersity allows these nanocrystals to self-assemble with a long-range ordering in two-dimensional and three-dimensional supracrystals. According to the nanocrystal shape, simple cubic or face-centered cubic supracrystals are observed. It is remarkable to notice that well-faceted supracrystals with sizes on the order of 10 microm may be obtained.

Substantial improvement of nanotube processability by freeze-drying.

As-produced carbon nanotubes often contain a fraction of impurities such as metal catalysts, inorganic supports, and carbon by-products. These impurities can be partially removed by using acidic dissolution. The resulting nanotube materials have to be dried to form a powder. The processability of nanotubes subjected to regular (thermal vaporisation) drying is particularly difficult because capillary forces pack and stick the nanotubes irreversibly, which limits their dispersability in polymeric matrices or solvents. We show that this dramatic limitation can be circumvented by using freeze-drying instead of regular-drying during nanotube purification process. In this case, the nanotubes are trapped in frozen water which is then sublimated. As a result the final powder is significantly less compact and, more important, the nanotubes can be easily dispersed with no apparent aggregates, thereby greatly enhancing their processability, e.g., they can be used to make homogeneous composites and fibers. Results from coagulation spinning from water-based dispersions of regularly-dried and freeze-dried nanotubes are compared. We also show that freeze-dried materials, in contrast to regularly-dried materials, can be dissolved in organic polar solvents using alkali-doped nanotubes. High resolution TEM and XRD analysis demonstrate that the nanotube structure and quality are not affected at the nanoscale by freeze-drying treatments.

Hot-drawing of single and multiwall carbon nanotube fibers for high toughness and alignment.

We report a new hot-drawing process for treating wet-spun composite fibers made of single- and multiwall carbon nanotubes and poly(vinyl alcohol). As shown in previous reports, untreated composite nanotube fibers exhibit a very large strain-to-failure, and their toughness, which is the energy needed to break the fibers, exceeds that of any other known materials. However, untreated composite nanotube fibers absorb a very small amount of energy at low strain and become degraded in humid conditions. In this work, we use hot-drawing treatments, a concept inspired from textile technologies, to improve the properties of nanotube/PVA fibers. This treatment yields a crystallinity increase of the PVA and an unprecedented degree of alignment of the nanotubes. These structural modifications lead to a markedly improved energy absorption at low strain and make the fibers resistant to moisture. Hot-drawn nanotube/PVA fibers hold great potential for a number of applications such as bulletproof vests, protective textiles, helmets, and so forth.

Transforming growth factor beta 1 production by CD4+ CD25+ regulatory T cells in peripheral blood mononuclear cells from healthy subjects stimulated with Leishmania guyanensis.

Transforming growth factor beta (TGF-beta) has been shown to be a central immunomodulator used by leishmaniae to escape effective mechanisms of protection in human and murine infections with these parasites. However, all the information is derived from studies of established infection, while little is known about TGF-beta production in response to Leishmania stimulation in healthy subjects. In this study, TGF-beta1 production was demonstrated in peripheral blood mononuclear cells from healthy subjects never exposed to leishmaniae in response to live Leishmania guyanensis, and the TGF-beta1-producing cells were described as a distinct subpopulation of CD4(+) CD25(+) regulatory T cells. The suppressive properties of CD4(+) CD25(+) T cells were demonstrated in vitro by their inhibition of production of interleukin 2 (IL-2) and IL-10 by CD4(+) CD25(-) T cells in the presence of either anti-CD3 or L. guyanensis. Although neutralization of TGF-beta1 did not reverse the suppressive activity of CD4(+) CD25(+) T cells activated by anti-CD3, it reversed the suppressive activity of CD4(+) CD25(+) T cells activated by L. guyanensis. Altogether our data demonstrated that TGF-beta1 is involved in the suppressive activity of L. guyanensis-stimulated CD4(+) CD25(+) T cells from healthy controls.

[Diagnosis of Mycobacterium ulcerans infections in French Guiana]. / Diagnostic de l'infection à Mycobacterium ulcerans en Guyane française.

THE SITUATION: Buruli's ulcer is a severe necrotic cutaneous infection due to Mycobacterium ulcerans. It is a major public health problem in developing countries. FROM A CLINICAL POINT OF VIEW: The early stage of the infection corresponds to a painless cutaneous nodule, whereas the late stage corresponds to ulceration with detachment of the edges. There is currently no other treatment than surgical excision combined with heat therapy. FROM A DIAGNOSTIC POINT OF VIEW: Three methods can be used: direct examination of swabs stained according to Ziehl-Neelsen's method, culture in specific medium at 32 degrees C and the polymerization chain reaction assay (PCR). The latter is the technique of choice.

Bundles of identical double-walled carbon nanotubes.

In a sample produced by catalytic chemical vapor deposition (CCVD), the structure of the carbon nanotubes (diameter and helicity) which governs their electronic properties, is determined by electron diffraction. We found that most of the smallest bundles are constituted of identical double-walled carbon nanotubes.

Original magnetic alignment of a nematic phase containing single-walled nanotubes.

Dispersions of single-walled carbon nanotubes in a 4-pentyl-4'-cyano-biphenyl nematic liquid crystal matrix are studied by X-ray scattering. For some mixtures, the addition of nanotubes strongly modifies the properties of the matrix: under a magnetic field, the nematic director is aligned perpendicular to the field, whereas it is parallel to it for pure 4-pentyl-4'-cyano-biphenyl. This original modification of liquid crystal alignment by the addition of nanotubes raises new questions about nanotubes and liquid crystal interactions.

Increased production of interferon-gamma by Leishmania homologue of the mammalian receptor for activated C kinase-reactive CD4+ T cells among human blood mononuclear cells: an early marker of exposure to Leishmania?

A prospective study was undertaken to define early predictive immunological marker(s) of exposure to Leishmania in naïve subjects who have never been exposed to any Leishmania and who were also free of any cutaneous leishmaniasis lesions. These naïve subjects could have been exposed to Leishmania in a rain forest where Leishmania guyanensis and their natural vectors and mammalian host are cocirculating. The production of interferon (IFN)-gamma in response to the Leishmania homologue of the mammalian receptor for activated c kinase (LACK), a candidate for vaccine against leishmaniasis was analysed. At the end of their stay in the rain forest, LACK-specific CD8+ T cells were detected in subjects whose peripheral blood mononuclear cell (PBMC) produced IFN-gamma in response to soluble Leishmania antigens (SLA) and in those whose PBMC remained unresponsive to SLA. However, LACK-specific CD4+ T cells were detected only in PBMCs from individuals who became IFN-gamma responders to SLA. In subjects whose PBMC became positive to SLA, LACK-reactive CD4+ T cells producing high level of IFN-gamma were detectable before the SLA-reactive IFN-gamma producing CD4+ T cells, suggesting that the former readout assay could be used as an early predictive immunological marker of exposure to Leishmania in subjects who remained disease free.

The use of the murine model of infection with Leishmania major to reveal the antagonistic effects that IL-4 can exert on T helper cell development and demonstrate that these opposite effects depend upon the nature of the cells targeted for IL-4 signaling.

In contrast to mice from the majority of inbred strains, BALB mice develop aberrant Th2 responses and suffer progressive disease after infection with Leishmania major. These outcomes depend on the production of Interleukin 4, during the first 2 d of infection, by CD4+ T cells that express the Vbeta4-Valpha8 T cell receptors specific for a dominant I-A(d) restricted epitope of the LACK antigen from L. major. In contrast to this well established role of IL-4 in Th2 cell maturation, we have recently shown that, when limited to the initial period of activation of dendritic cells by L. major preceding T cell priming, IL-4 directs DCs to produce IL-12, promotes Th1 cell maturation and resistance to L. major in otherwise susceptible BALB/c mice. Thus, the antagonistic effects that IL-4 can have on Th cell development depend upon the nature of the cells (DCs or primed T cells) targeted for IL-4 signaling.

High intralesional interleukin-10 messenger RNA expression in localized cutaneous leishmaniasis is associated with unresponsiveness to treatment.

The intralesional expression of cytokines (interleukin [IL]-4, IL-13, IL-10, and interferon-gamma) was analyzed in 65 patients with localized cutaneous leishmaniasis due to Leishmania guyanensis before specific treatment with pentamidine isethionate. The local expression of IL-10 was significantly higher in patients who responded poorly to treatment than in patients whose lesions were regressing. When an IL-10 level >10 (ratio of the concentration of IL-10 [pg/microL] to that of beta-actin [pg/microL]) was used as an indicator of treatment failure, the sensitivity of this test was 78.6, and the specificity was 72.5. Thus, high intralesional expression of IL-10 might predict a poor response to conventional treatment.

IL-4 instructs TH1 responses and resistance to Leishmania major in susceptible BALB/c mice.

Immunity to infection with intracellular pathogens is regulated by interleukin 12 (IL-12), which mediates protective T helper type 1 (TH1) responses, or IL-4, which induces TH2 cells and susceptibility. Paradoxically, we show here that when present during the initial activation of dendritic cells (DCs) by infectious agents, IL-4 instructed DCs to produce IL-12 and promote TH1 development. This TH1 response established resistance to Leishmania major in susceptible BALB/c mice. When present later, during the period of T cell priming, IL-4 induced TH2 differentiation and progressive leishmaniasis in resistant mice. Because immune responses developed via the consecutive activation of DCs and then T cells, the contrasting effects of IL-4 on DC development and T cell differentiation led to immune responses that had opposing functional phenotypes.

Unresponsiveness of specific T cells to IL-12 is associated with active cutaneous leishmaniasis owing to Leishmania guyanensis.

The production of interleukin (IL)-13 and unresponsiveness to IL-12 in T cells were analyzed in patients with active localized cutaneous leishmaniasis (untreated or not responsive to treatment) and in patients who had been treated successfully for the disease. More IL-13 was produced by specific T cells in response to Leishmania guyanensis (L. guyanensis) antigens in active compared to in inactive leishmaniasis. Furthermore, unresponsiveness of specific T cells to IL-12 was detected only in patients with active leishmaniasis, i.e. in patients with detectable parasites such as untreated patients and patients unresponsive to treatment. These results support that IL-12 unresponsiveness of Leishmania-specific T cells is responsible for the persistence of infection.

Metal-insulator and structural phase transition observed by ESR spectroscopy and x-ray diffraction in KC60.

We have performed electron spin resonance (ESR) spectroscopy and x-ray diffraction experiments at low temperature on KC60 single crystals. ESR data reveal the occurrence of a metal-insulator phase transition at about 50 K. In the same temperature range, we observe the stabilization of a superstructure which doubles the volume of the unit cell. We suggest that displacements of the K atoms and a modulation of the C60 charge may be involved in the mechanism of this phase transition. These results shed new light on the subtle interplay of structure, dimensionality, and electronic properties in the AC60 fullerides.