Nanoparticle assemblies via coordination with a tetrakis(terpyridine) linker bearing a rigid tetrahedral core

Controlling particle-particle interactions is a major challenge in achieving the programmable assembly of nanoparticles, which shows great potential for device fabrication and detection systems. We present here a simple chemical method that allows the formation of Pd nanoparticle assemblies using a tetrakis(terpyridine) linker with a rigid tetrahedral core.

Synthesis of diazenido-ligated vanadium nanoparticles

Metallic vanadium nanoparticles stabilized with 4-octylphenyldiazenido groups (particle size: 1.7 ± 0.2 nm) were synthesized via the reduction of VCl4 with superhydride (LiBHEt3) in the presence of 4-octylphenyldiazonium salt in an Ar-filled glovebox. The resulting particles were characterized using TEM, elemental analysis, and XPS measurements. The unusual reaction on the surface resulted in the passivation of V-N═N-Ar covalent bonds.

A new method to generate arene-terminated Si(111) and Ge(111) surfaces via a palladium-catalyzed arylation reaction

Formation of silicon-aryl and germanium-aryl direct bonds on the semiconductor surface is a key issue to realize molecular electronic devices, but the conventional methods based on radical intermediates have problems to accompany the side reactions. We developed the first example of versatile and efficient methods to form clean organic monolayers with Si-aryl and Ge-aryl bonds on hydrogen-terminated silicon and germanium surfaces by applying our original catalytic arylation reactions of hydrosilanes and hydrogermanes using Pd catalyst and base in homogeneous systems. We could immobilize aromatic groups with redox-active and photoluminescent properties, and further applied in the field of rigid π-conjugated redox molecular wire composites, as confirmed by the successive coordination of terpyridine molecules with transition metal ions. The surfaces were characterized using cyclic voltammetry (CV), water contact angle measurements, X-ray photoelectron spectroscopy (XPS), fluorescence spectroscopy, and atomic force microscopy (AFM). Especially, the AFM analysis of 17 nm-long metal complex molecular wires confirmed their vertical connection to the plane surface.

Adverse effects of coexistence of sarcopenia and metabolic syndrome in Japanese women

BACKGROUND/OBJECTIVES

Little information is available regarding the interactions of sarcopenia and metabolic syndrome (MetS) in the risks of these age-associated diseases in women. The present cross-sectional study was performed to investigate whether the coexistence of sarcopenia and MetS further increases the risks of lifestyle-related diseases in Japanese women.

SUBJECTS/METHODS

Healthy Japanese women (n=533) aged 30-84 participated in this study. MetS was defined as higher body mass index, fasting plasma glucose, systolic or diastolic blood pressure and blood lipid abnormalities. Appendicular muscle mass and bone mineral density (BMD) were measured using dual-energy X-ray absorptiometry. The criterion of low muscle mass and strength defined median skeletal muscle index (appendicular muscle mass/height², kg/m²) and handgrip strength.

RESULTS

Two-way ANCOVA with adjustment for age, body fat percentage and whole-body lean tissue mass indicated that sarcopenia and MetS interacted to produce a significant effect on HbA1c, systolic blood pressure, triglycerides and brachial-ankle pulse wave velocity in Japanese women. The systolic blood pressure, triglycerides and brachial-ankle pulse wave velocity were significantly higher in women with coexisting sarcopenia and MetS than in healthy controls or in those with sarcopenia or MetS alone. The HbA1c in the coexisting sarcopenia and MetS group was higher than in healthy controls and sarcopenia subjects.

CONCLUSIONS

The coexistence of sarcopenia and MetS further increases the risks of cardiovascular diseases, such as type 2 diabetes mellitus, hypertension, arterial stiffness and hyperlipidemia even adjustment of age and body composition in adult Japanese women.

Near-threshold photoproduction of Lambda(1520) from protons and deuterons

Photoproduction of Lambda(1520) with liquid hydrogen and deuterium targets was examined at photon energies below 2.4 GeV in the SPring-8 LEPS experiment. For the first time, the differential cross sections were measured at low energies and with a deuterium target. A large asymmetry of the production cross sections from protons and neutrons was observed at backward K+/0 angles. This suggests the importance of the contact term, which coexists with t-channel K exchange under gauge invariance. This interpretation was compatible with the differential cross sections, decay asymmetry, and photon beam asymmetry measured in the production from protons at forward K+ angles.

Surface immobilization of PSI using vitamin K1-like molecular wires for fabrication of a bio-photoelectrode

We present a bio-photoelectrode made of photosystem I complex (PSI) of cyanobacteria, Thermosynechococcus elongatus, and molecular wires. The newly designed and synthesized molecular wire similar to vitamin K1 (VK1) has a naphthoquinone moiety that can connect to PSI, and a terpyridine moiety for connection to a Co(II) ion. Surface immobilization of PSI and molecular wires was performed by a self-assembled monolayer (SAM) formation process at indium tin oxide (ITO) followed by stepwise coordination reactions. The PSI-immobilized ITO showed a photocurrent action spectrum, whose profile was consistent with that of PSI. We have demonstrated a new method for the immobilization of PSI on the electrode surface, useful in the construction of phovoltaic cells or photon-sensing devices.

A dose–response relation between aerobic exercise and visceral fat reduction: systematic review of clinical trials

OBJECTIVE

It has been suggested that exercise has preferential effects on visceral fat reduction. However, the dose-response effect remains unclear because of limited evidence from individual studies. The purpose of this study was to systematically review the current literature to establish whether reduction of visceral fat by aerobic exercise has a dose-response relationship.

METHODS

A database search was performed (PubMed, 1966-2006) with appropriate keywords to identify studies exploring the effects of aerobic exercise as a weight loss intervention on visceral fat reduction. Visceral fat reduction was expressed as the percentage of visceral fat change per week (%DeltaVF/w). The energy expenditure by aerobic exercise was expressed as Sigma (metabolic equivalents x h per week (METs x h/w)).

RESULTS

Nine randomized control trials and seven non-randomized control trials were selected. In most of the studies, the subjects performed aerobic exercise generating 10 METs x h/w or more. Among all the selected groups (582 subjects), visceral fat decreased significantly (P<0.05) in 17 groups during the intervention, but not in the other 4 groups. There was no significant relationship between METs x h/w from aerobic exercise and %DeltaVF/w in all the selected groups. However, when subjects with metabolic-related disorders were not included (425 subjects), METs x h/w from aerobic exercise had a significant relationship with %DeltaVF/w (r=-0.75). Moreover, visceral fat reduction was significantly related to weight reduction during aerobic exercise intervention, although a significant visceral fat reduction may occur without significant weight loss.

CONCLUSION

These results suggest that at least 10 METs x h/w in aerobic exercise, such as brisk walking, light jogging or stationary ergometer usage, is required for visceral fat reduction, and that there is a dose-response relationship between aerobic exercise and visceral fat reduction in obese subjects without metabolic-related disorders.

Fluctuations in carotid arterial distensibility during the menstrual cycle do not influence cardiovagal baroreflex sensitivity

AIM

Fluctuations in autonomic nervous functions throughout the menstrual cycle and the underlying mechanism concerning them are not well known. This study was designed to test the hypothesis that fluctuations in cardiovagal baroreflex sensitivity (BRS) throughout the menstrual cycles of young women are due to fluctuations in carotid arterial distensibility.

METHODS

In eight eumenorrhoeic healthy young women (18-24 years), we determined the variations in the carotid arterial distensibility coefficient (DC; via simultaneous ultrasonography and applanation tonometry), cardiovagal BRS (phase IV of the Valsalva manoeuvre and the sequence method; up- or down-sequence spontaneous BRS), and serum oestradiol and progesterone concentrations at five points in the menstrual cycle (menstrual = M, follicular = F, ovulatory = O, early luteal = EL, and late luteal = LL).

RESULTS

Serum oestradiol and progesterone levels were consistent with the predicted cycle phases. Carotid arterial DC fluctuated cyclically, increasing significantly from the M (52.4 +/- 4.9 x 10(-3) kPa(-1), mean +/- SE) and F (52.7 +/- 4.4) phases to the O (57.6 +/- 4.4) phase and declining sharply in the EL (46.0 +/- 4.0) and LL (45.1 +/- 3.0) phases (F = 6.37, P < 0.05). Contrary to our prediction, however, cardiovagal BRS by the Valsalva manoeuvre (P = 0.73) or sequence method (up-sequence spontaneous BRS; P = 0.84: down-sequence spontaneous BRS; P = 0.67) did not change significantly during the menstrual cycle.

CONCLUSION

The results suggest that, although carotid arterial distensibility fluctuates with the changes in ovarian hormone levels that occur during the menstrual cycle, the fluctuations in carotid arterial distensibility do not influence cardiovagal BRS.

Effect of aging on carotid artery stiffness and baroreflex sensitivity during head-out water immersion in man

To examine the possible age-related blood pressure (BP) deregulation in response to central hypervolemia, we measured spontaneous baroreflex sensitivity (SBRS), carotid arterial compliance (CC), and R-R interval coefficient of variation (RRICV) during basal and thermoneutral resting head-out-of-water immersion (HOWI) in 7 young (YG = 24.0 +/- 0.8 years) and 6 middle-aged/older (OL = 59.3 +/- 1.3 years) healthy men. Compared with basal conditions (YG = 19.6 +/- 4.0 vs OL = 6.1 +/- 1.5 ms/mmHg, P < 0.05), SBRS remained higher in YG than OL during rest HOWI (YG = 23.6 +/- 6.6 vs OL = 9.3 +/- 2.1 ms/mmHg, P < 0.05). The RRICV was significantly different between groups (YG = 6.5 +/- 1.4 vs OL = 2.8 +/- 0.4%, P < 0.05) under HOWI. The OL group had no increase in CC, but a significant increase in systolic BP (basal = 115.3 +/- 4.4 vs water = 129.3 +/- 5.3 mmHg, P < 0.05) under HOWI. In contrast, the YG group had a significant increase in CC (basal = 0.16 +/- 0.01 vs water = 0.17 +/- 0.02 mm(2)/mmHg, P < 0.05) with no changes in systolic BP. SBRS was positively related to CC (r = 0.58, P < 0.05 for basal vs r = 0.62, P < 0.05 for water). Our data suggest that age-related vagal dysfunction and reduced CC may be associated with SBRS differences between YG and OL groups, and with BP elevation during HOWI in healthy older men.

Non-invasive assessment of cardiac output during exercise in healthy young humans: comparison between Modelflow method and Doppler echocardiography method

AIMS

The Modelflow method can estimate cardiac output from arterial blood pressure waveforms using a three-element model of aortic input impedance (aortic characteristic impedance, arterial compliance, and systemic vascular resistance). We tested the reliability of a non-invasive cardiac output estimation during submaximal exercise using the Modelflow method from finger arterial pressure waveforms collected by Portapres in healthy young humans.

METHODS

The Doppler echocardiography method was used as a reference method. Sixteen healthy young subjects (nine males and seven females) performed a multi-stage cycle ergometer exercise at an intensity corresponding to 70, 90, 110 and 130% of their individual ventilatory threshold for 2 min each. The simultaneous estimation of cardiac output (15 s averaged data) using the Modelflow and Doppler echocardiography methods was performed at rest and during exercise.

RESULTS AND CONCLUSION

The Modelflow-estimated cardiac output correlated significantly with the simultaneous estimates by the Doppler method in all subjects (r = 0.87, P < 0.0001) and the SE of estimation was 1.93 L min-1. Correlation coefficients in each subject ranged from 0.91 to 0.98. Although the Modelflow method overestimated cardiac output, the errors between two estimates were not significantly different among the exercise levels. These results suggest that the Modelflow method using Portapres could provide a reliable estimation of the relative change in cardiac output non-invasively and continuously during submaximal exercise in healthy young humans, at least in terms of the relative changes in cardiac output.

Annexin-1 (lipocortin-1)-immunoreactivity in the folliculo-stellate cells of rat anterior pituitary: the effect of adrenalectomy and corticosterone treatment on its subcellular distribution

In the pituitary gland, annexin-1 (lipocortin-1) located in folliculo-stellate (FS) cells has been advocated as one of the candidates for paracrine agents produced by FS cells that modulate the release of pituitary hormones. However, the expression and distribution pattern of annexin-1 in FS cells under different circulating corticosteroid conditions has not been examined. Thus, by means of pre-embedding immunoelectron microscopy, we investigated the expression of annexin-1 in FS cells under different corticosteroid conditions. Annexin-1-immunoreactivity was observed in the cytoplasm; especially intense immunoreactivity was detected in the follicle surface of FS cells under control conditions. After adrenalectomy, annexin-1-immunoreactivity almost disappeared, but the immunoreactivity recovered with corticosterone replacement. The expression of glucocorticoid receptor immunoreactivity in the nucleus of FS cells also showed a similar pattern to annexin-1 associated with the changes in the corticosteroid conditions. However, S-100 immunoreactivity, a marker for FS cells, was not changed whatever the corticosteroid conditions. These results confirm that glucocorticoids regulate the annexin-1 expression and demonstrate the translocation of annexin-1 from intracellular to pericellular sites in the FS cells of the rat anterior pituitary gland.

Current status of hospice cancer deaths both in-unit and at home (1995-2000), and prospects of home care services in Japan

In Japan, the first government-approved hospice (GAH) and palliative care unit was established and commenced operations in 1990, and hospice medical care was made eligible for health insurance coverage. By 31 December 2000, the number of GAH institutions had increased to 86 (1,590 beds). The ratio of hospices to population in Japan is currently approximately 1:1.5 million, with an average of one hospice bed for approximately every 80,000 people. This study of institutions reports a survey conducted to determine the number of deaths (hospice unit and home) of GAH cancer patients, and to determine the servicing status of hospice home care for the period 1995 through 2000. The place of death of the patients cared for by GAHs in 2000 were: hospice units 97.7% and home 2.3%. GAH patient deaths (both inpatient and at home) in 2000 was 2.6% of the total number of cancer patients' deaths, an increase of 3.8-fold since 1995. Of the total number of GAH institutions, 62% are engaged in home care services and 91 % offer hospice care by hospice-assigned doctors. In addition, 72% offer team care with nurses based at Home Care Agencies. In order for the hospice (including home care service) to become established in a way most appropriate to each region of Japan, GAH institutions must assume significant promotional roles in their respective regions. One of the goals and assignments of establishing medical service with hospice home care in Japan is to develop the systematic care programs of GAH institutions, which include home care service in addition to the already established hospice unit and outpatient services.

Effects of endurance training on resting and post-exercise cardiac autonomic control

PURPOSE

Endurance training induces reductions in both resting and postexercise heart rate (HR). If adaptation in cardiac autonomic regulation is a contributing factor in these reductions, changes in cardiac autonomic nervous system (ANS) should correspond to those in HR during an endurance-training program. We investigated the changes in resting and postexercise HR variabilities (both in the time and frequency domain) over a 6-wk training program.

METHODS

HR variability was measured five times in an endurance-training group (N = 7) and four times in a control group (N = 5) during the course of study.

RESULTS

Endurance training decreased HR and increased indices of parasympathetic modulation measured both at rest and during postexercise recovery periods. Noteworthy is that no changes in either HR or indices of ANS modulation measured during postexercise recovery periods were detectable after the first 7 d of the study despite continued changes in resting HR and indices in ANS modulation measured between the 7th and 42nd days of the endurance-training program.

CONCLUSIONS

The study demonstrates that with endurance-training changes in cardiac ANS modulation partly contribute to a decrease in HR at rest and during postexercise recovery period, and that adaptation of the cardiac autonomic control occurs sooner in immediate postexercise periods than at rest.

Effects of one-legged endurance training on femoral arterial and venous size in healthy humans

The cross-sectional area (CSA) of large-conductance arteries increases in response to endurance training in humans. To determine whether training-induced changes in arterial structure are systemic in nature or, rather, are confined to the arteries supplying exercising muscles, we studied 10 young men who performed one-legged cycle training [80% of one-legged peak O2 uptake (VO2 peak)), 40 min/day, 4 days/wk] for 6 wk and detraining for another 6 wk. There were no significant differences in baseline one-legged VO2 peak) and CSA of the common femoral artery and vein (via B-mode ultrasound) between experimental and control legs. In the experimental leg, one-legged VO2 peak) increased 16% [from 3.0 +/- 0.1 to 3.4 +/- 0.1 (SE) l/min], arterial CSA increased 16% (from 84 +/- 3 to 97 +/- 5 mm2), and venous CSA increased 46% (from 56 +/- 5 to 82 +/- 5 mm2) after endurance training. These changes returned to baseline during detraining. There were no changes in one-legged VO2 peak) and arterial CSA in the control leg, whereas femoral venous CSA in the control leg significantly increased 24% (from 54 +/- 5 to 67 +/- 4 mm2) during training. Changes in femoral arterial and venous CSA in the experimental leg were positively and significantly related to corresponding changes in one-legged VO2 peak) (r = 0.86 and 0.76, respectively), whereas there were no such relations in the control leg (r = 0.10 and 0.17). When stepwise regression analysis was performed, a primary determinant of change in VO2 peak) was change in femoral arterial CSA, explaining approximately 70% of the variability. These results support the hypothesis that the regional increase in blood flow, rather than systemic factors, is associated with the training-induced arterial expansion. Femoral arterial expansion may contribute, at least in part, to improvement in efficiency of blood transport from the heart to exercising muscles and may facilitate achievement of aerobic work capacity.

Effects of water depth on abdominal [correction of abdominails] aorta and inferior vena cava during standing in water

During water immersion bradycardia and increase in stroke volume induce by changing in hydrostatic pressure. We hypothesised that the cardiac alterations with immersion are associates with an increase in venous return from lower body. Because the venous return reflects volume of capacitance vein e.g, inferior vena cava. Therefore, we clarified the effects of water immersion on the size in left ventricle, aorta, and vena cava.