Longitudinal changes in life-space mobility and the factors influencing it among chronic community-dwelling post-stroke patients.

PURPOSE: To identify longitudinal changes in life-space mobility and the factors influencing it among chronic, stable post-stroke patients. MATERIALS AND METHODS: This prospective study included Japanese post-stroke patients who received day-care rehabilitation services and could undergo three life-space mobility assessments (at baseline, 12, and 24 months) for over 2 years, using the Life-Space Assessment (LSA) tool. Physical function, cognitive function, and activities of daily living were assessed by self-selected comfortable gait speed, Mini-Mental State Examination (MMSE), and Functional Independence Measure Motor subscale (FIM motor) scores, respectively, in addition to age, sex, time from onset, stroke type, and comorbidities. A multivariable linear mixed-effects model was used to examine the longitudinal changes in LSA scores and associated factors. RESULTS: A total of 89 participants were enrolled. At baseline, the median age was 74 years, 33% were women, and median time from onset was 75 months. The LSA scores significantly declined over the two-year period. In the multivariate linear mixed-effects model adjusted for clinical characteristics, comfortable gait speed and age were significantly associated with changes in the LSA score, independent of FIM motor scores and MMSE scores. CONCLUSIONS: Life-space mobility may persistently decline, and gait function may be a determinant influencing these changes in community-dwelling chronic post-stroke patients.Implications for RehabilitationLimited life-space mobility leads to less frequent participation in social activities and an increased risk of adverse health outcomes such as hospitalization.Changes in life-space mobility should be considered in the rehabilitation care plan for chronic post-stroke patients.Life-space mobility may decline persistently in stable post-stroke patients, even if they have periodically received day-care rehabilitation services.Since gait speed is a predominant factor affecting life-space mobility, regular assessment of gait function and appropriate strategies are needed to prevent deterioration of gait speed in chronic post-stroke patients.

Ephrin type-A receptor 2 on tumor-derived exosomes enhances angiogenesis through the activation of MAPK signaling.

Exosomes are potent players in the development of metastases and they play an important role in cancer angiogenesis and exacerbation. However, it is unclear how proteins on exosomes affect development of blood vessel networks. In this study, we focused on relationships between membrane proteins on exosomes and angiogenesis using human umbilical vein endothelial cells (HUVEC). Lung tumor cell-derived exosomes induced tube formation and growth of endothelial cells in vitro in a dose-dependent manner involving MAPK activation, but this was not seen in normal lung epithelial cells. Ephrin type-A receptor 2 (EphA2) was identified by proteomic analysis and an inhibition assays showed it is a major MAPK activator on exosomes. Thus EphA2 on exosomes participates in angiogenesis as a ligand of the ephrin signaling pathway. These results support the development of novel therapeutic strategies such as blockade of remote cancer communications through exosomes.

Generation of a sensitive TNFR2-specific murine assays system.

Tumor necrosis factor (TNF)/TNF receptors (TNFR1/TNFR2) are considered to be potential drug targets to treat refractory diseases, including autoimmune diseases and malignant tumors. However, their specific functions, especially in the case of TNFR2, are poorly understood. In this study, we constructed a mouse TNFR2 (mTNFR2)-mediated biological assay system that shows no effects of mouse TNFR1 (mTNFR1) in order to screen mTNFR2-selective stimulating agents. Mouse TNFR1(-/-)R2(-/-) preadipocytes were transfected with the gene encoding the mTNFR2/mouse Fas (mFas) chimeric receptor in which the extracellular and transmembrane domains of mTNFR2 were fused to the intracellular domain of mFas. Our results demonstrated that this cell line exhibits highly sensitive mTNFR2-mediated cytotoxic effects. We propose that this mTNFR2-mediated biological assay system would be a useful tool to screen for mTNFR2-selective stimulating agents.

High-dose cutaneous exposure to mite allergen induces IgG-mediated protection against anaphylaxis.

BACKGROUND: The relationship among natural allergen exposure, induction of blocking antibody and the occurrence of atopic allergy-particularly in the presence of IgE production-is debatable. OBJECTIVE: To clarify the relationship between the dose of cutaneous exposure to dust mite allergen and susceptibility to the IgE-mediated allergic response in relation to IgG production. METHODS: NC/Nga mice were epicutaneously exposed to various doses of Dermatophagoides pteronyssinus allergen to induce atopic dermatitis-like skin lesions. We then evaluated the skin lesions, induction of mite-specific immune responses, and susceptibility to anaphylaxis. RESULTS: Dose-dependent exacerbation of atopic dermatitis-like skin lesions and increases in mite-specific IgG and IgE production were observed. However, mice exposed to relatively low doses of mite allergen showed hypersusceptibility to mite allergen-specific anaphylaxis. We also showed that adoptive transfer of total IgG from Dp-sensitized mice rescued mice from the hypersusceptibility seen in those exposed to low doses of mite allergen. CONCLUSIONS AND CLINICAL RELEVANCE: High-dose cutaneous exposure to dust mites induced effective blocking IgG production, even if accompanied by IgE production. Our data might support the concept that an increase in IgG titre, not a decrease in IgE titre, is a marker of clinical improvement in allergen-specific immunotherapy.

Wavelength-selective light-triggered strand exchange reaction.

We prepared an oligodeoxynucleotide (ODN) bearing two 4-hydroxy-2-mercaptobenzimidazole nucleobase analogues (SB(NV) and SB(NB)) modified with different photolabile groups. This ODN enabled a light-triggered strand exchange reaction in a wavelength-selective manner.

Conversion of a light-driven proton pump into a light-gated ion channel.

Interest in microbial rhodopsins with ion pumping activity has been revitalized in the context of optogenetics, where light-driven ion pumps are used for cell hyperpolarization and voltage sensing. We identified an opsin-encoding gene (CsR) in the genome of the arctic alga Coccomyxa subellipsoidea C-169 that can produce large photocurrents in Xenopus oocytes. We used this property to analyze the function of individual residues in proton pumping. Modification of the highly conserved proton shuttling residue R83 or its interaction partner Y57 strongly reduced pumping power. Moreover, this mutation converted CsR at moderate electrochemical load into an operational proton channel with inward or outward rectification depending on the amino acid substitution. Together with molecular dynamics simulations, these data demonstrate that CsR-R83 and its interacting partner Y57 in conjunction with water molecules forms a proton shuttle that blocks passive proton flux during the dark-state but promotes proton movement uphill upon illumination.

C5-azobenzene-functionalized locked nucleic acid uridine: isomerization properties, hybridization ability, and enzymatic stability.

Oligonucleotides (ONs) modified with a locked nucleic acid (LNA) are widely used in the fields of therapeutics, diagnosis, and nanotechnology. There have been significant efforts towards developing LNA analogues bearing modified bridges to improve their hybridization ability, nuclease resistance, and pharmacokinetic profiles. Moreover, nucleobase modifications of LNA are useful strategies for the functionalization of ONs. Modifications of the C5-position of pyrimidine nucleobases are particularly interesting because they enable predictable positioning of functional groups in the major groove of the duplex. Here we report the synthesis of C5-azobenzene-functionalized LNA uridine (LNA-U(Az)) and properties of LNA-U(Az)-modified ONs, including isomerization properties, hybridization ability, and enzyme stability. LNA-U(Az) in ON is photo-isomerized effectively and reversibly by irradiation at 365 nm (trans to cis) and 450 nm (cis to trans). LNA-U(Az)-modified ONs show RNA-selective hybridization ability despite the large hydrophobic azobenzene moiety extending into the major groove of the duplex. The enzymatic stability of LNA-U(Az)-modified ONs is higher than that of natural and LNA-modified ONs with or without photo-irradiation. Our results indicate that LNA-U(Az) holds promise for RNA targeting and photo-switchable technologies.

Circulating Tumor Cells as an Independent Predictor of Survival in Advanced Gastric Cancer.

BACKGROUND: When the indication for surgery of highly advanced gastric cancer is considered, careful selection of the patients is important. In addition to tumor-node-metastasis factors and peritoneal lavage cytology (CY), which are important predictors of prognosis, detection of circulating tumor cells (CTCs) could be another potential marker. METHODS: This study prospectively evaluated CTCs using a semi-automated immunomagnetic separation system (CellSearch) for 136 patients with advanced gastric cancer to determine the frequency of CTC positivity. For 123 patients who also had their CY evaluated, the significance of both CTC and CY, was investigated as a potential biomarker to predict progression-free survival (PFS) or to monitor the therapeutic effect. RESULTS: In 25 patients (18.4 %), CTCs were positive. Positive CTC counts were more common for tumors with diffuse histologic type and distant metastasis. The PFS of CTC-positive patients was significantly shorter than that of CTC-negative patients (hazard ratio 2.03; P = 0.016). A multivariate analysis of 123 patients showed that CTC and CY as well as performance status and macroscopic distant metastasis were independent factors for PFS. When both CTC and CY were converted to negative values by therapeutic interventions, long-term PFS was achieved. CONCLUSIONS: Detection of CTCs was an independent predictor of a shorter PFS in advanced gastric cancer. For selecting patients who require intensive treatment, CTCs could be a valuable biomarker. The combined status of CTC and CY would be useful in selecting patients for radical surgery. Further investigation with a larger number of patients is necessary to establish the importance of CTCs.

Biochemical and hematologic effects of polyvinylpyrrolidone-wrapped fullerene C60 after oral administration.

The fullerene C60 is used in consumer products such as cosmetics owing to its antioxidative effects and is being developed for nanomedical applications. However, knowledge regarding the safety of fullerene C60, especially after oral administration, is sparse. Here, we examined the safety of fullerene C60 in mice after 7 d of exposure to orally administered polyvinylpyrrolidone (PVP)-wrapped fullerene C60 (PVP-fullerene C60). Mice treated with PVP-fullerene C60 showed few changes in the plasma levels of various markers of kidney and liver injury and experienced no significant hematologic effects. Furthermore, the histology of the colon of PVP-fullerene C60-treated mice was indistinguishable from that of control mice. These results suggest that PVP-fullerene C60 lacks toxicity after high-dose oral administration and indicate that PVP-fullerene C60 can be considered safe for oral medication. These data provide basic information that likely will facilitate the production of safe and effective forms of fullerene C60.