Factors that facilitate multigenerational exchanges in regional locations: a cross-sectional study in Niigata City, Japan.

BACKGROUND: In the process of community building, it is important to create a place for multigenerational exchanges. To promote multigenerational exchanges in regional locations, it is essential to clarify whether such exchanges are related to government infrastructure, regional characteristics, and social capital, and how these exchanges contribute to community building. METHODS: A cross-sectional questionnaire study was conducted with representatives from 455 Chiiki no Cha-no-Ma (literal translation "community living room," and hereafter "Cha-no-Ma") in Niigata City, Japan. Responses were received from 405 representatives (response rate: 89.0 %), and 401 agreed to participate (4 declined). The survey details included basic information (e.g., date each location was established, frequency of meetings, number of caretakers and participants, qualifications of the representative), activities reflecting local culture, a social capital scale, the effects of the Cha-no-Ma implemented by the representative (12 items), challenges for management (16 items), and the implementation of multigenerational exchanges. RESULTS: Most of the age groups that participated in the Cha-no-Ma were elderly, and multigenerational exchanges took place in 125 locations (31.5 %). Items that had a significant connection to the implementation of multigenerational exchanges were "Frequency of meetings" (p < 0.001) and "Activities reflecting local culture" (p = 0.026). Binomial logistic regression analysis indicated that a high frequency of meetings was associated with the implementation of multigenerational exchanges (Odds ratio = 3.839). There was a significantly higher ratio of implementation of multigenerational exchanges when the effects were a "connection with the region" (p = 0.006) and "conversations with different generations" (p = 0.004), and when the challenge was "no support from residents" (p = 0.002). CONCLUSIONS: Cha-no-Ma participation is low among young people. The following ideas can be considered in order to increase multigenerational exchanges in regional locations. These exchanges may be promoted by increasing the frequency of meetings with qualified personnel and by adding activities that reflect local culture, such as festivals and making local foods. This community-based study clearly indicates that implementing multigenerational exchanges is an important activity for community building because it is related to connection within the community.

Implementation and evaluation of a primary diabetes prevention programme for young adult employees in Japan: A non-randomized controlled trial.

Aim: To determine the effects of a primary diabetes prevention programme created for healthy young adults. Design: This study was a non-randomized controlled trial. Methods: The participants were 20-39-year-old employees of two automobile sales companies. The intervention group (N = 154) received six original educational brochures and films created specifically for young adults, while the control group (N = 157) received none. Data were collected pre-intervention and immediately after and 10 weeks after intervention. Change in knowledge about diabetes, its prevention and health management were measured. Results: Overall, 129 interventions and 141 controls completed the trial. In items related to diabetes prevention, the intervention group increased their knowledge relative to controls (all p < .05). Awareness of susceptibility to diabetes also increased more in the interventions (p = .029). The interventions also improved more with items related to dietary behaviour (p < .05). This trial has been registered with UMIN-CTR clinical trial (UMIN000023749).

Carbon monoxide from heme oxygenase-2 Is a tonic regulator against NO-dependent vasodilatation in the adult rat cerebral microcirculation.

Although the brain generates NO and carbon monoxide (CO), it is unknown how these gases and their enzyme systems interact with each other to regulate cerebrovascular function. We examined whether CO produced by heme oxygenase (HO) modulates generation and action of constitutive NO in the rat pial microcirculation. Immunohistochemical analyses indicated that HO-2 occurred in neurons and arachnoid trabecular cells, where NO synthase 1 (NOS1) was detectable, and also in vascular endothelium-expressing NOS3, suggesting colocalization of CO- and NO-generating sites. Intravital microscopy using a closed cranial window preparation revealed that blockade of the HO activity by zinc protoporphyrin IX significantly dilates arterioles. This vasodilatation depended on local NOS activities and was abolished by CO supplementation, suggesting that the gas derived from HO-2 tonically regulates NO-mediated vasodilatory response. Bioimaging of NO by laser-confocal microfluorography of diaminofluorescein indicated detectable amounts of NO at the microvascular wall, the subdural mesothelial cells, and arachnoid trabecular cells, which express NOS in and around the pial microvasculature. On CO inhibition by the HO inhibitor, regional NO formation was augmented in these cells. Such a pattern of accelerated NO formation depended on NOS activities and was again attenuated by the local CO supplementation. Studies using cultured porcine aortic endothelial cells suggested that the inhibitory action of CO on NOS could result from the photo-reversible gas binding to the prosthetic heme. Collectively, CO derived from HO-2 appears to serve as a tonic vasoregulator antagonizing NO-mediated vasodilatation in the rat cerebral microcirculation.

Cadmium exposure alters metabolomics of sulfur-containing amino acids in rat testes.

This study aimed to examine distribution of cystathionine beta-synthase (CBS) and cystathionine gamma-lyase (CSE), the hydrogen sulfide (H(2)S)-generating enzymes, and metabolomic alterations in sulfur-containing amino acids in rat testes exposed to stressors. Immunohistochemistry revealed distinct distribution of the two enzymes: CBS occurred mainly in Leydig cells and was also detectable in Sertoli cells and germ cells, whereas CSE was evident in Sertoli cells and immature germ cells involving spermatogonia. The amounts of CSE and CBS in testes did not alter in response to administration of cadmium chloride, an antispermatogenic stressor leading to apoptosis. Metabolome analyses assisted by liquid chromatography equipped with mass spectrometry revealed marked alterations in sulfur-containing amino acid metabolism: amounts of methionine and cysteine were significantly elevated concurrently with a decrease in the ratio between S-adenosylhomocysteine and Sadenosylmethionine, suggesting expansion of the remethylation cycle and acceleration of methyl donation. Despite a marked increase in cysteine, amounts of H(2)S were unchanged, leading to a remarkable decline of the H(2)S/cysteine ratio in the cadmium-treated rats. Under such circumstances, oxidized glutathione (GSSG) was significantly reduced, whereas reduced glutathione (GSH) was well maintained, and the GSH/GSSG ratio was consequently elevated. These results collectively showed that cadmium induces metabolomic remodeling of sulfur-containing amino acids even when the protein expression of CBS or CSE is not evident. Although detailed mechanisms for such a remodeling event remain unknown, our study suggests that metabolomic analyses serve as a powerful tool to pinpoint a critical enzymatic reaction that regulates metabolic systems as a whole.

Hydrogen sulfide as an endogenous modulator of biliary bicarbonate excretion in the rat liver.

Cystathionine gamma-lyase (CSE) is an enzyme catalyzing cystathionine and cysteine to yield cysteine and hydrogen sulfide (H(2)S), respectively. This study aimed to examine if H(2)S generated from the enzyme could serve as an endogenous regulator of hepatobiliary function. Gas chromatographic analyses indicated that, among rat organs herein examined, liver constituted one of the greatest components of H(2)S generation in the body, at 100 mumol/g of tissue, comparable to that in kidney and 1.5-fold greater than that in brain, where roles of the gas in the regulation of neurotransmission were reported previously. At least half of the gas amount in the liver appeared to be derived from CSE, because blockade of the enzyme by propargylglycine suppressed it by 50%. Immunohistochemistry revealed that CSE occurs not only in hepatocytes, but also in bile duct. In livers in vivo, as well as in those perfused ex vivo, treatment with the CSE inhibitor induced choleresis by stimulating the basal excretion of bicarbonate in bile samples. Transportal supplementation of NaHS at 30 mumol/L, but not that of N-acetylcysteine as a cysteine donor, abolished these changes elicited by the CSE inhibitor in the perfused liver. The changes elicited by the CSE blockade did not coincide with alterations in hepatic vascular resistance, showing little involvement of vasodilatory effects of the gas in these events, if any. These results first provided evidence that H(2)S generated through CSE modulates biliary bicarbonate excretion and is thus a determinant of bile salt-independent bile formation in the rat liver.

Endocytosis of Multiwalled Carbon Nanotubes in Bronchial Epithelial and Mesothelial Cells.

Bronchial epithelial cells and mesothelial cells are crucial targets for the safety assessment of inhalation of carbon nanotubes (CNTs), which resemble asbestos particles in shape. Intrinsic properties of multiwalled CNTs (MWCNTs) are known to cause potentially hazardous effects on intracellular and extracellular pathways. These interactions alter cellular signaling and affect major cell functions, resulting in cell death, lysosome injury, reactive oxygen species production, apoptosis, and cytokine release. Furthermore, CNTs are emerging as a novel class of autophagy inducers. Thus, in this study, we focused on the mechanisms of MWCNT uptake into the human bronchial epithelial cells (HBECs) and human mesothelial cells (HMCs). We verified that MWCNTs are actively internalized into HBECs and HMCs and were accumulated in the lysosomes of the cells after 24-hour treatment. Next, we determined which endocytosis pathways (clathrin-mediated, caveolae-mediated, and macropinocytosis) were associated with MWCNT internalization by using corresponding endocytosis inhibitors, in two nonphagocytic cell lines derived from bronchial epithelial cells and mesothelioma cells. Clathrin-mediated endocytosis inhibitors significantly suppressed MWCNT uptake, whereas caveolae-mediated endocytosis and macropinocytosis were also found to be involved in MWCNT uptake. Thus, MWCNTs were positively taken up by nonphagocytic cells, and their cytotoxicity was closely related to these three endocytosis pathways.

Biological responses according to the shape and size of carbon nanotubes in BEAS-2B and MESO-1 cells.

This study aimed to investigate the influence of the shape and size of multi-walled carbon nanotubes (MWCNTs) and cup-stacked carbon nanotubes (CSCNTs) on biological responses in vitro. Three types of MWCNTs - VGCF(®)-X, VGCF(®)-S, and VGCF(®) (vapor grown carbon fibers; with diameters of 15, 80, and 150 nm, respectively) - and three CSCNTs of different lengths (CS-L, 20-80 µm; CS-S, 0.5-20 µm; and CS-M, of intermediate length) were tested. Human bronchial epithelial (BEAS-2B) and malignant pleural mesothelioma cells were exposed to the CNTs (1-50 µg/mL), and cell viability, permeability, uptake, total reactive oxygen species/superoxide production, and intracellular acidity were measured. CSCNTs were less toxic than MWCNTs in both cell types over a 24-hour exposure period. The cytotoxicity of endocytosed MWCNTs varied according to cell type/size, while that of CSCNTs depended on tube length irrespective of cell type. CNT diameter and length influenced cell aggregation and injury extent. Intracellular acidity increased independently of lysosomal activity along with the number of vacuoles in BEAS-2B cells exposed for 24 hours to either CNT (concentration, 10 µg/mL). However, total reactive oxygen species/superoxide generation did not contribute to cytotoxicity. The results demonstrate that CSCNTs could be suitable for biological applications and that CNT shape and size can have differential effects depending on cell type, which can be exploited in the development of highly specialized, biocompatible CNTs.

Culture medium type affects endocytosis of multi-walled carbon nanotubes in BEAS-2B cells and subsequent biological response.

We examined the cytotoxicity of multi-walled carbon nanotubes (MWCNTs) and the resulting cytokine secretion in BEAS-2B cells or normal human bronchial epithelial cells (HBEpCs) in two types of culture media (Ham's F12 containing 10% FBS [Ham's F12] and serum-free growth medium [SFGM]). Cellular uptake of MWCNT was observed by fluorescent microscopy and analyzed using flow cytometry. Moreover, we evaluated whether MWCNT uptake was suppressed by 2 types of endocytosis inhibitors. We found that BEAS-2B cells cultured in Ham's F12 and HBEpCs cultured in SFGM showed similar biological responses, but BEAS-2B cells cultured in SFGM did not internalize MWCNTs, and the 50% inhibitory concentration value, i.e., the cytotoxicity, was increased by more than 10-fold. MWCNT uptake was suppressed by a clathrin-mediated endocytosis inhibitor and a caveolae-mediated endocytosis inhibitor in BEAS-2B cells cultured in Ham's F12 and HBEpCs cultured in SFGM. In conclusion, we suggest that BEAS-2B cells cultured in a medium containing serum should be used for the safety evaluation of nanomaterials as a model of normal human bronchial epithelial cells. However, the culture medium composition may affect the proteins that are expressed on the cytoplasmic membrane, which may influence the biological response to MWCNTs.

Regulatory sequence elements of mouse GLUT4 gene expression in adipose tissues.

Ablation of GLUT4 in adipose tissues results in whole body insulin resistance and high-fat feeding down-regulates GLUT4 mRNA in white adipose tissues. Previous studies demonstrated that adipose tissue specific element(s) (ASE) of the murine GLUT4 gene is located between -551 and -442 relative to transcription start site and that high-fat responsive element(s) (HFRE) for down-regulation of the GLUT4 gene is located between bases -1001 and -442. To further characterize these regulatory elements, the regulation of GLUT4 minigenes containing -701, -551, and -506 bp of 5(')-flanking region was studied in transgenic mice. GLUT4 minigene mRNA from -506 transgenic mice did not express in adipose tissues, indicating that ASE located within 45 bp is located between bases -551 and -506. An 80-kDa of nuclear DNA binding protein was found to bind to a -TCCTCGTGGGAAGCG- element located between bases -551 and -537. High-fat diet feeding down-regulated GLUT4 minigene mRNA in -701 transgenic mice, but not in -551 transgenic mice, indicating that HFRE is located within 150 bp between bases -701 and -551 of the GLUT4 gene and is distinct from ASE.