Screening out the non-Arrhenius behaviour of nematic-isotropic transition by room temperature ionic liquid

Differential Scanning Calorimetry (DSC) and optical polarization microscopy of a mixture of the liquid crystalline material (N-(4-methoxybenzylidene)-4-butylaniline, MBBA) and a Fe-based room temperature ionic liquid 1-ethyl-3-methylimidazolium tetrachloroferrate ([Emim](+) [FeCl4](-), EMIF) indicate a decrease in the nematic-isotropic (N-I) phase transition temperature (T(NI)) with an increase in EMIF concentration, explained by a proposed model of Coulomb "screening" of MBBA quadrupoles by the EMIF ions along with ionic "self screening." DSC studies of EMIF-MBBA and pure EMIF and comparison with pure MBBA results show that the major transitions in pure EMIF have Arrhenius behaviour, but more importantly the previously found convex Arrhenius behaviour of the pristine MBBA [K. Dan et al., Europhys. Lett. 108, 36007 (2014)] becomes Arrhenius in the mixture, indicating a conversion of the entropic N-I activation barrier to an enthalpic one. In presence of EMIF, a drastic decrease in the intensity of out-of-plane distortions of benzene rings in MBBA is found from Fourier transform infrared spectroscopy, consistent with significant reduction in the conformational states of MBBA. This suppression of large amplitude motion is again consistent with a Coulomb screening and gives a molecular basis for the entropic-to-enthalpic conversion of the N-I activation barrier.

Micromotors working in water through artificial aerobic metabolism

Most catalytic micro/nanomotors that have been developed so far use hydrogen peroxide as fuel, while some use hydrazine. These fuels are difficult to apply because they can cause skin irritation, and often form and store disruptive bubbles. In this paper, we demonstrate a novel catalytic Pt micromotor that does not produce bubbles, and is driven by the oxidation of stable, non-toxic primary alcohols and aldehydes with dissolved oxygen. This use of organic oxidation mirrors living systems, and lends this new motor essentially the same characteristics, including decreased motility in low oxygen environments and the direct isothermal conversion of chemical energy into mechanical energy. Interestingly, the motility direction is reversed by replacing the reducing fuels with hydrogen peroxide. Therefore, these micromotors not only provide a novel system in nanotechnology, but also help in further revealing the underlining mechanisms of motility of living organisms.

PSORIASIS OCCURING IN YOUNG MONOZYGOTIC TWINS

Psoriasis occuring in monozygotic twins is reported. Although these patients had a different living environment since birth the similarity in psoriatic pattern and its time of onset suggested the strong influence of genetic factors. However the major histocompatibility antigens A2, A11, Bw(16), found in these patients were not those, which have been reported to be significantly increased among Japanese psoriatics.

Prostaglandin F2α FP receptor inhibitor reduces demyelination and motor dysfunction in a cuprizone-induced multiple sclerosis mouse model

Previously, we have demonstrated that prostamide/PGF synthase, which catalyzes the reduction of prostaglandin (PG) H2 to PGF2α, is constitutively expressed in myelin sheaths and cultured oligodendrocytes, suggesting that PGF2α has functional significance in myelin-forming oligodendrocytes. To investigate the effects of PGF2α/FP receptor signaling on demyelination, we administrated FP receptor agonist and antagonist to cuprizone-exposed mice, a model of multiple sclerosis. Mice were fed a diet containing 0.2% cuprizone for 5 weeks, which induces severe demyelination, glial activation, proinflammatory cytokine expression, and motor dysfunction. Administration of the FP receptor antagonist AL-8810 attenuated cuprizone-induced demyelination, glial activation, and TNFα expression in the corpus callosum, and also improved the motor function. These data suggest that during cuprizone-induced demyelination, PGF2α/FP receptor signaling contributes to glial activation, neuroinflammation, and demyelination, resulting in motor dysfunction. Thus, FP receptor inhibition may be a useful symptomatic treatment in multiple sclerosis.

Evaluation of insulin independence using 11C-methionine positron emission tomography after living-donor and brain-dead donor pancreas transplantation

We recently reported that (11)C-methionine positron-emission tomography (PET) is clinically useful for the evaluation of the pancreatic function of the living donor. The objective of this study was to evaluate the postoperative insulin independence in 10 living donor (LD) and 10 brain-dead donor (BD) pancreas transplantations for 20 patients with type I diabetes mellitus by using (11)C-methionine PET. After 6 months, PET/computed tomography was performed 30 minutes after (11)C-methionine (370-740 MBq) injection. The uptake in the pancreas was expressed as the standardized uptake value (SUV). Patient survival rates were 100% at 5 years for LD transplantations and at 2 years for BD transplantations. Insulin independence was 60% for LD transplantations at 5 years and 75% for BD transplantations at 2 years. There were no major surgical complications such as vascular thrombosis, intra-abdominal abscess, and graft pancreatitis. The SUVs for LD and BD pancreas transplantations with insulin independence were 7.2 ± 1.8 and 10.4 ± 2.3, respectively. The SUVs for LD pancreas transplantations with insulin dependence and BD pancreas transplantations with graft failure were 3.6 ± 1.1 and 2.9 ± 1.0, respectively. At 5 years after transplantation, for the LD transplants, the insulin-independent rate was 100% for the graft recipients with an SUV higher than 5, and the median insulin independence duration of the graft recipients with an SUV less than 5 was 7 months (P < .01). The (11)C-methionine PET may be a potent modality to predict long-term insulin independence and the avoidance of pancreas graft failure.

Thyroid antibodies are associated with stenotic lesions in the terminal portion of the internal carotid artery

BACKGROUND AND PURPOSE

Several studies have reported moyamoya syndrome associated with thyroid disease, and the mechanism involved in this relationship is unknown. This study aimed to clarify the involvement of thyroid antibodies and thyroid function in intracranial arterial stenosis.

METHODS

The study included 30 patients <65 years of age with intracranial arterial steno-occlusion. Patients with definitive moyamoya disease were excluded. Thyroid function and thyroid antibody levels were evaluated. The steno-occlusive site and the presence of moyamoya vessels were evaluated using digital subtraction angiography. The characteristics of intracranial arterial lesions were compared between patients with and without elevated thyroid antibody levels, and between patients with increased thyroid function and those with normal thyroid function.

RESULTS

Five patients had increased thyroid function and seven had elevated thyroid antibody levels. Four were diagnosed with Graves' disease, 13 with atherosclerotic intracranial stenosis, two with intracranial arterial dissection, one with vasculitis syndrome and 10 with intracranial stenosis of unknown cause. All patients with Graves' disease and patients with elevated antithyroid peroxidase antibody levels had steno-occlusion in the terminal portion of the internal carotid arteries, whereas most of the patients with normal thyroid function or without elevated thyroid antibody levels had stenosis in the middle cerebral arteries.

CONCLUSIONS

In young and middle-aged patients, a lesion in the terminal portion of the internal carotid artery was associated with elevated thyroid antibody levels and increased thyroid function. Stenoses found in the terminal portion of the internal carotid artery and immune-mediated thyroid diseases may share a common background.

Management of angiogram-negative acute colonic hemorrhage: safety and efficacy of colonoscopy-guided superselective embolization

BACKGROUND

We evaluated the efficacy and safety of superselective embolization with assistance of colonoscopy for acute colonic hemorrhage.

METHODS

Of 92 cases of acute colonic hemorrhage requiring colonoscopic intervention, 11 (12 %) could not be successfully treated. Of these, 10 patients (9 men, mean age 65.5 years, range 39-75 years) underwent superselective embolization. Hemorrhage was caused by diverticular disease (n = 8), polypectomy (n = 1), and vascular malformation (n = 1). In all 10 cases, the radiopaque clips were placed at the bleeding point via colonoscopy. Microcatheters were used in all procedures, and embolization was performed at the level of the vasa recta leading to or near the clips with Gelfoam particles, microcoils, or both.

RESULTS

Immediate hemostasis was achieved in all patients. In 6 of 10 patients (60 %), selective angiograms showed no active extravasation at the time of the procedure and the embolization was performed using clips as a landmark. In the remaining four patients, selective angiograms showed active extravasation from the vasa recta leading to the clips. The mean number of embolized vessels with no active extravasation and with active extravasation was 1.83 (range 1-3) and 1.25 (range 1-2), respectively. The mean duration of clinical follow-up was 11.6 months (range 1-29 months). One patient (10 %) bled from a different site than the treated site a month after embolization, but the bleeding ceased after endoscopic intervention. All the patients (100 %) were evaluated for objective evidence of ischemia by colonoscopy. Four of the 10 patients (40 %) were found endoscopically to have small areas of ischemia involving only the mucosa, but they remained asymptomatic. There was no bowel infarction or stricture.

CONCLUSIONS

Colonoscopy-assisted superselective embolization may be a safe and useful procedure for acute colonic hemorrhage without active extravasation on angiogram.

Chemosensory signals and their receptors in the olfactory neural system

Chemical communication is widely used among various organisms to obtain essential information from their environment required for life. Although a large variety of molecules have been shown to act as chemical cues, the molecular and neural basis underlying the behaviors elicited by these molecules has been revealed for only a limited number of molecules. Here, we review the current knowledge regarding the signaling molecules whose flow from receptor to specific behavior has been characterized. Discussing the molecules utilized by mice, insects, and the worm, we focus on how each organism has optimized its reception system to suit its living style. We also highlight how the production of these signaling molecules is regulated, an area in which considerable progress has been recently made.

Field Hypothesis on the Self-regulation of Gene Expression

The mechanism of the self-regulation of gene expression in living cells is generally explained by considering complicated networks of key-lock relationships, and in fact there is a large body of evidence on a hugenumber of key-lock relationships. However, in the present article we stress that with the network hypothesis alone it is impossible to fully explain the mechanism of self-regulation in life. Recently, it has been established that individual giant DNA molecules, larger than several tens of kilo base pairs, undergo a large discrete transition in their higher-order structure. It has become clear that nonspecific weak interactions with various chemicals, suchas polyamines, small salts, ATP and RNA, cause on/off switching in the higher-order structure of DNA. Thus, the field parameters of the cellular environment should play important roles in the mechanism of self-regulation, in addition to networks of key and locks. This conformational transition induced by field parameters may be related to rigid on/off regulation, whereas key-lock relationships may be involved in a more flexible control of gene expression.

A lifetime experience of violence and adverse reproductive outcomes: findings from population surveys in India

Intimate partner violence (IPV) is a global public health issue that threatens the reproductive health of women. Despite a growing demand for research on the potential threat of IPV in relation to adverse reproductive outcomes, there have been no population-based studies of India. The current study analyzed the National Family Health Survey 3, which contained detailed information on types of violence in relation to the single question of pregnancy outcomes. The dataset was used to assess the association between a lifetime experience of IPV and terminated pregnancies among married Indian women. Multiple logistic regression analysis was then used to assess the association between these variables, controlling for socio-demographic characteristics. Results showed that 39.6% of Indian women have experienced violence by their husbands, while 18.3% of women have terminated a pregnancy during their lifetimes. The odds ratio of a terminated pregnancy among women who had experienced any type of partner violence was 1.62 (95% CI (confidence interval) = 1.51-1.73). All combinations of violence except a combination of emotional and sexual violence were associated with an increased risk of a terminated pregnancy. These results suggest that prevention of IPV would reduce the high incidence of terminated pregnancies, thus improving maternal health in India.

Gas Sensing Based on a Nonlinear Response: Discrimination between Hydrocarbons and Quantification of Individual Components in a Gas Mixture

A novel sensing system is proposed based on the multidimensional information contained in a dynamic nonlinear response. A sinusoidal temperature change was applied to a SnO(2) semiconductor gas sensor, and the resulting output conductance of the sensor was analyzed by fast Fourier transformation (FFT). The higher harmonics of the FFT characterized the nonlinear properties of the response. The amplitudes of the higher harmonics of the FFT exhibit characteristic changes which depend on the chemical structure, concentration, and the kinetics of adsorption and the reaction of hydrocarbon gases and aromatic vapors on the sensor surface. In addition, it is possible to distinguish between gases in a gaseous mixture with a single detector using this dynamic nonlinear response. Nonlinear responses are discussed in relation to the kinetics of the reaction at the sensor surface and the temperature-dependent barrier potential of the semiconductor.

Ablation of demineralized dentin using a mid-infrared tunable nanosecond pulsed laser at 6 μm wavelength range for selective excavation of carious dentin

In dental clinic, some lasers have already realized the optical drilling of dental hard tissue. However, conventional lasers lack the ability to discriminate and excavate carious tissue only, and still depend on the dentist's ability. The objective of this study is to develop a selective excavation of carious dentin by using the laser ablation with 6 μm wavelength range. Bovine dentin demineralized with lactic acid solution was used as a carious dentin model. A mid-infrared tunable pulsed laser was obtained by difference-frequency generation technique. The wavelength was tuned around the absorption bands called amide 1 and amide 2. In the wavelength range from 5.75 to 6.60 μm, the difference of ablation depth between demineralized and normal dentin was observed. The wavelength at 6.02 μm and the average power density of 15 W/cm(2), demineralized dentin was removed selectively with less-invasive effect on normal dentin. The wavelength at 6.42 μm required the increase of average power density, but also showed the possibility of selective ablation. In the near future, development of compact laser device will open the minimal invasive laser treatment to the dental clinic.