Presenteeism and sleep duration on workdays and days off

BACKGROUND

Presenteeism refers to being present at work but experiencing reduced productivity due to health problems, and has been known to be related to sleep loss. Workers commonly sleep longer on days off than on workdays, and presenteeism may be reduced with extended sleep on days off.

AIMS

This study aimed to determine the association between sleep duration both on workdays and days off and presenteeism.

METHODS

The participants were 1967 workers who engaged in work for 5 days and rested for 2 days weekly. Sleep duration was classified into less than 6 hours (short; S), 6-8 hours (medium; M), and 9 hours or longer (long; L), for workdays and days off, respectively. Presenteeism was assessed using the World Health Organization Health and Work Performance Questionnaire.

RESULTS

On both workdays and days off, compared to medium sleep duration, short sleep duration was significantly associated with increased odds of presenteeism. The odds of presenteeism were significantly increased for S-S (odds ratio [OR] 2.17, 95% confidence interval [CI]1.40-3.37), S-M (OR 1.59, 95% CI 1.14-2.22), S-L (OR 2.71, 95% CI 1.05-7.00), and M-S (OR 6.82, 95% CI 2.71-17.17) combined sleep duration for workdays and days off, respectively, compared to an M-M (reference).

CONCLUSIONS

Sleep loss on workdays cannot be compensated for with longer sleep on days off. This study suggests that sufficient sleep duration on both workdays and days off is important for reducing presenteeism.

Recognition of pathogen-derived sphingolipids in Arabidopsis

In plants, many invading microbial pathogens are recognized by cell-surface pattern recognition receptors, which induce defense responses. Here, we show that the ceramide Phytophthora infestans-ceramide D (Pi-Cer D) from the plant pathogenic oomycete P. infestans triggers defense responses in Arabidopsis. Pi-Cer D is cleaved by an Arabidopsis apoplastic ceramidase, NEUTRAL CERAMIDASE 2 (NCER2), and the resulting 9-methyl-branched sphingoid base is recognized by a plasma membrane lectin receptor-like kinase, RESISTANT TO DFPM-INHIBITION OF ABSCISIC ACID SIGNALING 2 (RDA2). 9-Methyl-branched sphingoid base is specific to microbes and induces plant immune responses by physically interacting with RDA2. Loss of RDA2 or NCER2 function compromised Arabidopsis resistance against an oomycete pathogen. Thus, we elucidated the recognition mechanisms of pathogen-derived lipid molecules in plants.

Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

Colletotrichum shisoi sp. nov., an anthracnose pathogen of Perilla frutescens in Japan: molecular phylogenetic, morphological and genomic evidence

Species of the fungal genus Colletotrichum are among the most devastating pathogens of agricultural crops in the world. Based on DNA sequence data (ITS, GAPDH, CHS-1, ACT, TUB2) and morphology, we revealed Colletotrichum isolates infecting the oil crop Perilla frutescens, commonly known as shiso, to represent a previously unknown species of the C. destructivum species complex and described it as C. shisoi. We found that C. shisoi appears to be able to adopt a hemibiotrophic lifestyle, characterised by the formation of biotrophic hyphae followed by severe necrotic lesions on P. frutescens, but is less virulent on Arabidopsis, compared to its close relative C. higginsianum which also belongs to the C. destructivum species complex. The genome of C. shisoi was sequenced, annotated and its predicted proteome compared with four other Colletotrichum species. The predicted proteomes of C. shisoi and C. higginsianum, share many candidate effectors, which are small, secreted proteins that may contribute to infection. Interestingly, C. destructivum species complex-specific secreted proteins showed evidence of increased diversifying selection which may be related to their host specificities.

Genome Sequence Resources for Four Phytopathogenic Fungi from the Colletotrichum orbiculare Species Complex

Colletotrichum orbiculare species complex fungi are hemibiotrophic plant pathogens that cause anthracnose of field crops and weeds. Members of this group have genomes that are remarkably expanded relative to other Colletotrichum fungi and compartmentalized into AT-rich, gene-poor and GC-rich, gene-rich regions. Here, we present an updated version of the C. orbiculare genome, as well as draft genomes of three other members from the C. orbiculare species complex: the alfalfa pathogen C. trifolii, the prickly mallow pathogen C. sidae, and the burweed pathogen C. spinosum. The data reported here will be important for comparative genomics analyses to identify factors that play a role in the evolution and maintenance of the expanded, compartmentalized genomes of these fungi, which may contribute to their pathogenicity.

Nosocomial infection by human bocavirus and human rhinovirus among paediatric patients with respiratory risks

BACKGROUND

Nosocomial infections by respiratory viruses undetected by rapid tests are not often diagnosed. For paediatric patients with background diseases, nosocomial infection could be fatal.

AIM

To determine the relationship between developing symptoms by respiratory viruses undetectable by rapid tests and respiratory risks and to improve the management of infection control.

METHODS

Two episodes of nosocomial infection by human bocavirus (HBoV) and human rhinovirus (HRV) were retrospectively investigated in a tertiary hospital paediatric ward in Japan. Viruses were identified by polymerase chain reaction to determine infection control management. When viruses of the same species were detected from different patients, the virus homology was investigated. The relationship between respiratory risks and developing symptoms was statistically investigated.

FINDINGS

Three and four patients with respiratory risks in the HBoV and HRV outbreaks, respectively, developed respiratory symptoms. The nucleotide sequences of two patients in the HBoV outbreak and all four patients in the HRV outbreak were phylogenetically close. In both outbreaks, the patients with respiratory risks developed significantly more symptoms than those without any risk (P = 0.035 and 0.018, respectively). After the patients with respiratory infection were separated from those with respiratory risks, no additional nosocomial infection occurred.

CONCLUSION

Patients with respiratory risks easily develop respiratory symptoms and acquire severe symptoms of nosocomial infection by those viruses. In a paediatric ward, we should adopt not only standard precautions but also isolation management of the patients with respiratory symptoms, even if they have negative results in rapid tests.

Successful Treatment of Stricture of Duct-to-Duct Biliary Anastomosis After Living-Donor Liver Transplantation of the Left Lobe: A Case Report

Biliary complications, such as stricture or obstruction, after living-donor liver transplantation (LDLT) remain major problems to be solved. Magnetic compression anastomosis (MCA) is a minimally invasive method of biliary anastomosis without surgery in patients with biliary stricture or obstruction. A 66-year-old woman had undergone LDLT for end-stage liver disease for primary biliary cholangitis 20 months previously at another hospital. Computerized tomography showed dilation of the intrahepatic bile duct (B2). Because B2 was invisible with the use of endoscopic retrograde cholangiopancreatography, percutaneous transhepatic biliary drainage (PTBD) was performed for treatment of cholangitis. The rendezvous technique failed because a guidewire could not pass through the biliary stricture. Therefore, we decided to perform MCA. A parent magnet was endoscopically placed distally in the common bile duct of the stricture, and a daughter magnet attached to a guidewire was inserted proximally through the fistula tract of the PTBD. Both magnets were positioned across the stricture, and the 2 magnets were pulled to each other by magnetic power, to sandwich the stricture. By 14 days after MCA, a fistula between B2 and the common bile duct was created. At 28 days after MCA, the magnets were removed distally and a 16-French tube was placed across the fistula. At 7 months after MCA, that tube was removed. In conclusion, when a conventional endoscopic or percutaneous approach including the rendezvous technique fails, MCA is a good technique for biliary stricture after LDLT.

Clinical factors associated with the symptoms of constipation in patients with diabetes mellitus: A multicenter study

BACKGROUND AND AIM

Changes in treatment protocols for patients with diabetes mellitus (DM) may influence the functions of the digestive tract. This study examined possible clinical factors associated with the symptoms of constipation in patients with DM.

METHODS

This was a multicenter study. Participants were consecutive Japanese patients undergoing treatment for type 1 or type 2 DM. Constipation was evaluated using the gastrointestinal symptom rating scale. Diabetic neuropathy was evaluated by the presence or absence of peripheral neuropathy of the lower limbs.

RESULTS

Of 419 participants, 258 were men and 161 women (ratio: 1.6:1), with a mean age of 63.6 ± 12.5 years. In multivariate analysis, symptoms of constipation were significantly associated with age (odds ratio [OR] = 1.02, 95% confidence interval [CI]: 1.01-1.04, P = 0.032), lower mental component summary (OR = 3.31, 95% CI: 1.69-6.48, P < 0.001), diabetic retinopathy (OR = 1.99, 95% CI: 1.14-3.45, P = 0.015), and diabetic neuropathy (OR = 1.86, 95% CI: 1.10-3.16, P = 0.021). In patients with peripheral neuropathy of the lower limbs, regardless of the presence of other complications (diabetic nephropathy and diabetic retinopathy), the prevalence of symptoms of constipation was twice that of patients without peripheral neuropathy (40.0-49.1% vs 22.0%). Diabetic drugs were not associated with symptoms of constipation.

CONCLUSIONS

Diabetic neuropathy, defined as peripheral neuropathy of the lower limbs, was significantly associated with symptoms of constipation. Peripheral neuropathy of the lower limbs is not a direct risk factor for constipation but may be a useful criterion when assessing whether constipation is associated with DM.

Evaluation of ozonated water using ASTM E1174 for standardized testing of handwash formulations for healthcare personnel

Removal of bacteria by handwashing with ozonated water was evaluated using the ASTM E1174 standard test method. Thirty healthy volunteers were assigned randomly to three groups: ozonated water, antimicrobial soap and water, and non-antimicrobial soap and water. A 3 log₁₀ cfu reduction was achieved by washing hands with ozonated water or antimicrobial soap and water. However, ozonated water was not significantly superior to non-antimicrobial soap and water. Ozonated water may remove bacteria from the hands to at least a similar extent as that by non-antimicrobial soap and water in the absence of visible dirt or body fluid contamination.

Effect of temperature on diapause termination and post-diapause development in Eotetranychus smithi (Acari: Tetranychidae)

Previous studies on the spider mite Eotetranychus smithi Pritchard & Baker have shown that diapause in eggs is induced by low temperature alone and that females developed at ≤ 17.5 °C laid diapause eggs, regardless of the photoperiod. In this study, diapause eggs were kept at 5 °C and a photoperiod of 16L:8D for 0-120 days and then maintained at 25 °C to know the effect of chilling on diapause termination. Diapause eggs mostly hatched when they were maintained at 25 °C after chilling for 30-90 days at 5 °C, which suggests that diapause termination is favored by low temperatures. To clarify the hatching conditions after diapause termination, diapause eggs kept at 5 °C for 45 days were subsequently maintained at various constant temperatures (from 15 to 25 °C) under a long-day photoperiod (16L:8D). The hatchability at all temperatures tested was high (> 90%) and did not significantly differ among the high temperatures. Duration of embryonic development was shorter with increasing warming temperature after chilling. The lower thermal threshold (t) and thermal constant (k) for post-diapause egg development were 10.5 °C and 76.9 degree-days, respectively. Females, which developed from diapause eggs that were chilled at 5 °C for 45 days and then maintained at 15 °C, laid only non-diapause eggs, which indicates that they were prevented from re-entering diapause even under diapause-inducing conditions (15 °C). Thus, temperature is the main factor to control diapause termination and post-diapause development, which has also been found for other spider mites that enter diapause at the egg stage.

Stim1 Regulates Enamel Mineralization and Ameloblast Modulation

Loss-of-function mutations in the Ca²⁺ release-activated Ca²⁺ channel genes ORAI1 and STIM1 abolish store-operated Ca²⁺ entry (SOCE) and result in ectodermal dysplasia with amelogenesis imperfecta. However, because of the limited availability of patient tissue, analyses of enamel mineralization or possible changes in ameloblast function or morphology have not been possible. Here, we generated mice with ectodermal tissue-specific deletion of Stim1 ( Stim1 cKO [conditional knockout]), Stim2 ( Stim2 cKO), and Stim1 and Stim2 ( Stim1/2 cKO) and analyzed their enamel phenotypes as compared with those of control ( Stim1/2^fl/fl) animals. Ablation of Stim1 and Stim1/2 but not Stim2 expression resulted in chalky enamel and severe attrition at the incisor tips and molar cusps. Stim1 and Stim1/2 cKO, but not Stim2 cKO, demonstrated inferior enamel mineralization with impaired structural integrity, whereas the shape of the teeth and enamel thickness appeared to be normal in all animals. The gene expression levels of the enamel matrix proteins Amelx and Ambn and the enamel matrix proteases Mmp20 and Klk4 were not altered by the abrogation of SOCE in Stim1/2 cKO mice. The morphology of ameloblasts during the secretory and maturation stages was not significantly altered in either the incisors or molars of the cKO animals. However, in Stim1 and Stim1/2 cKO incisors, the alternating modulation of maturation-stage ameloblasts between the smooth- and ruffle-ended cell types continued beyond the regular cycle and extended to the areas corresponding to the zone of postmodulation ameloblasts in the teeth of control animals. These results indicate that SOCE is essential for proper enamel mineralization, in which Stim1 plays a critical role during the maturation process.

Impact of constant versus fluctuating temperatures on the development and life history parameters of Tetranychus urticae (Acari: Tetranychidae)

The impact of daily temperature fluctuations on arthropod life history parameters is inadequately studied compared with the ample amount of research that has been conducted on the effects of constant temperatures. Fluctuating temperatures are likely to be more realistic, as they are ecologically more similar to what these arthropods experience in nature. Here, we compared the impact of 11 constant temperatures that ranged from 10 to 35 °C with fluctuating temperatures with the same corresponding mean temperature and an amplitude of 10 °C between high (12 h) and low (12 h) temperatures on the development and life history parameters of Tetranychus urticae under continuous light conditions. No eggs hatched at constant 10 °C, whereas 81.5% of eggs successfully completed development at fluctuating 10 °C (15/5 °C). Egg-to-female adult development was faster under fluctuating temperatures from 12.5 to 27.5 °C than under constant temperatures, whereas the opposite trend was observed at >30 °C. The lower thermal thresholds (T) were 11.63 and 8.63 °C, and thermal constants (K) were 127.81 and 150.69 degree-days for egg-to-female adults at constant and fluctuating temperatures, respectively. The numbers of oviposition days were significantly higher at fluctuating 15 °C than at the corresponding constant temperature, whereas the opposite trend was observed from 20 to 30 °C. The intrinsic rate of increase (r) was higher at fluctuating than at constant 15 °C. The net reproductive rate (R ₀) was also higher at fluctuating than at constant 15 and 35 °C, but showed an opposite trend at 20 and 25 °C. We conclude that fluctuating temperatures should be considered to accurately predict spider mite population dynamics in nature.

Significance of Portal Venous Velocity in Short-term Graft Function in Living Donor Liver Transplantation

BACKGROUND

Graft regeneration and functional recovery after reperfusion of transplanted graft are very important for successful living donor liver transplantation (LDLT). The aim of this study was to evaluate the significance of postoperative portal venous velocity (PVV) in short-term recovery of graft function in LDLT.

PATIENTS AND METHODS

From February 2007 through December 2015, we performed 17 primary LDLTs, which were included in the present study. The patients ranged in age from 12 to 65 years (mean: 50 years), and 11 were female patients. Postoperatively, Doppler ultrasonography was performed daily to measure PVV (cm/s), and liver function parameters were measured daily. The change in PVV (ΔPVV) was defined as follows: ΔPVV = PVV on postoperative day (POD) 1 - PVV on POD 7. Maximal value of serum aspartate aminotransferase (ASTmax) and maximal value of serum alanine transaminase (ALTmax) at 24 hours after graft reperfusion were used as parameters of reperfusion injury. Correlation analyses were performed as follows: (1) correlation of ΔPVV and PVV on POD 1 (PVV-POD 1) with the values such as ASTmax, ALTmax, other liver function parameters on POD 7 and graft regeneration rate; (2) correlation of ASTmax and ALTmax with other liver function parameters on POD 7.

RESULTS

ΔPVV significantly correlated with the values of serum total bilirubin (P < .01), prothrombin time (P < .01), and platelet count (P < .05), and PVV-POD 1 significantly correlated with the values of serum total bilirubin (P < .05) and prothrombin time (P < .05).

CONCLUSION

ΔPVV and PVV-POD 1 may be useful parameters of short-term functional recovery of the transplant liver in LDLT.

Draft Genome Assembly of Colletotrichum chlorophyti, a Pathogen of Herbaceous Plants

Colletotrichum chlorophyti is a fungal pathogen that infects various herbaceous plants, including crops such as legumes, tomato, and soybean. Here, we present the genome of C. chlorophyti NTL11, isolated from tomato. Analysis of this genome will allow a clearer understanding of the molecular mechanisms underlying fungal host range and pathogenicity.

Proposal of a new mechanism for the directional propagation of the action potential using a mimicking system

A nerve conduction model is constructed by using some liquid-membrane cells that mimic the function of the K⁺ and Na⁺ channels. By imitating two types of Na⁺ channels (ligand-gated Na⁺ channels and voltage-gated Na⁺ channels), a new mechanism for the directional propagation of the action potential along the axon toward the axon terminal is proposed. When the nerve cell is excited by an external (outer) stimulus, it can be presumed that the ligand-gated channels work as power sources at the synapse to propagate the change in the membrane potential, and then the voltage-gated channels locally assist the propagation at each site of the axon (nodes of Ranvier).

Note: Novel diamond anvil cell for electrical measurements using boron-doped metallic diamond electrodes

A novel diamond anvil cell suitable for electrical transport measurements under high pressure has been developed. A boron-doped metallic diamond film was deposited as an electrode on a nano-polycrystalline diamond anvil using a microwave plasma-assisted chemical vapor deposition technique combined with electron beam lithography. The maximum pressure that can be achieved by this assembly is above 30 GPa. We report electrical transport measurements of Pb up to 8 GPa. The boron-doped metallic diamond electrodes showed no signs of degradation after repeated compression.

A novel and selective sodium-glucose cotransporter-2 inhibitor, tofogliflozin, improves glycaemic control and lowers body weight in patients with type 2 diabetes mellitus

AIM

To assess the efficacy, safety and tolerability of different doses of tofogliflozin, a novel, highly selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, in patients with type 2 diabetes mellitus (T2DM).

METHODS

In a 12-week, multicentre, multinational, randomized, double-blind, parallel-group, placebo-controlled, dose-finding study, patients with inadequate glycaemic control from diet and exercise alone, or from diet and exercise plus a stable dose of metformin, were randomized to one of five doses of tofogliflozin (2.5, 5, 10, 20, or 40 mg) or placebo. The primary efficacy endpoint was absolute change at week 12 from baseline in glycated haemoglobin (HbA1c), minus the change in the placebo group.

RESULTS

Statistically significant dose-dependent reductions in HbA1c were shown in all treated groups except the 2.5-mg dose group, with a maximum reduction of 0.56% (placebo-subtracted) at the 40-mg dose, along with increased urinary glucose excretion. Metformin treatment had no substantial influence on tofogliflozin efficacy. Dose-dependent reductions in fasting plasma glucose and body weight were observed, and glucose intolerance was improved, with a trend towards blood pressure reduction. Slight increases were observed for mean ketone bodies with no abnormal change in ketone body ratio. No deaths or treatment-related serious adverse events were reported. The incidence of adverse events was similar in the placebo (37.9%) to that in the tofogliflozin group (35.9-46.3%). Withdrawal because of adverse events was rare (≤2 patients per treatment group), with similar rates of withdrawal in the placebo and tofogliflozin groups.

CONCLUSIONS

A once-daily dose of tofogliflozin for 12 weeks was an effective, safe and well-tolerated treatment for T2DM.

DEEP BIOSPHERE. Exploring deep microbial life in coal-bearing sediment down to ~2.5 km below the ocean floor

Microbial life inhabits deeply buried marine sediments, but the extent of this vast ecosystem remains poorly constrained. Here we provide evidence for the existence of microbial communities in ~40° to 60°C sediment associated with lignite coal beds at ~1.5 to 2.5 km below the seafloor in the Pacific Ocean off Japan. Microbial methanogenesis was indicated by the isotopic compositions of methane and carbon dioxide, biomarkers, cultivation data, and gas compositions. Concentrations of indigenous microbial cells below 1.5 km ranged from <10 to ~10(4) cells cm(-3). Peak concentrations occurred in lignite layers, where communities differed markedly from shallower subseafloor communities and instead resembled organotrophic communities in forest soils. This suggests that terrigenous sediments retain indigenous community members tens of millions of years after burial in the seabed.

A Pharmacokinetic/Pharmacodynamic Drug-Drug Interaction Study of Tofogliflozin (a New SGLT2 Inhibitor) and Selected Anti-Type 2 Diabetes Mellitus Drugs

OBJECTIVE

Tofogliflozin is an oral hypoglycemic agent with a novel mechanism of action that reduces blood glucose levels by promoting glucose excretion in urine, achieved by selectively inhibiting sodium-glucose co-transporter 2 (SGLT2). We evaluated the effects of several selected anti-type 2 diabetes mellitus (T2DM) drugs-glimepiride, metformin, sitagliptin, pioglitazone, miglitol, nateglinide, and voglibose-on the pharmacokinetics and pharmacodynamics of tofogliflozin, and the effects of tofogliflozin on the pharmacokinetics of these anti-T2DM drugs in healthy male volunteers.

METHODS

A single dose of either tofogliflozin alone, one of the anti-T2DM drugs alone, or co-administration of tofogliflozin and the anti-T2DM drug was administered to 108 healthy men. Cmax, AUCinf, and cumulative urine glucose excretion after co-administration of tofogliflozin and each of the anti-T2DM drugs was evaluated relative to the values of those parameters after administration of each drug alone.

RESULTS

None of the anti-T2DM drugs had any effect on tofogliflozin exposure. Tofogliflozin had no or little effect on the exposure of any anti-T2DM drug. No anti-T2DM drug had any major effect on the cumulative urine glucose excretion induced by tofogliflozin. There were no safety concerns evident after administration of any drug alone or in co-administration.

CONCLUSIONS

Neither the pharmacokinetics nor the pharmacodynamics of tofogliflozin was affected by any of the anti-T2DM drugs evaluated in this study, nor was the pharmacokinetics of any of the anti-T2DM drugs affected by tofogliflozin in healthy male volunteers.

Exosomal microRNA in serum is a novel biomarker of recurrence in human colorectal cancer

Background:

Functional microRNAs (miRNAs) in exosomes have been recognised as potential stable biomarkers in cancers. The aim of this study is to identify specific miRNAs in exosome as serum biomarkers for the early detection of recurrence in human colorectal cancer (CRC).

Methods:

Serum samples were sequentially obtained from six patients with and without recurrent CRC. The miRNAs were purified from exosomes, and miRNA microarray analysis was performed. The miRNA expression profiles and copy number aberrations were explored using microarray and array CGH analyses in 124 CRC tissues. Then, we validated exosomal miRNAs in 2 serum sample sets (90 and 209 CRC patients) by quantitative real-time RT–PCR.

Results:

Exosomal miR-17-92a cluster expression level in serum was correlated with the recurrence of CRC. Exosomal miR-19a expression levels in serum were significantly increased in patients with CRC as compared with healthy individuals with gene amplification. The CRC patients with high exosomal miR-19a expression showed poorer prognoses than the low expression group (P<0.001).

Conclusions:

Abundant expression of exosomal miR-19a in serum was identified as a prognostic biomarker for recurrence in CRC patients.

Oxytocin's neurochemical effects in the medial prefrontal cortex underlie recovery of task-specific brain activity in autism: a randomized controlled trial

The neuropeptide oxytocin may be an effective therapeutic strategy for the currently untreatable social and communication deficits associated with autism. Our recent paper reported that oxytocin mitigated autistic behavioral deficits through the restoration of activity in the ventromedial prefrontal cortex (vmPFC), as demonstrated with functional magnetic resonance imaging (fMRI) during a socio-communication task. However, it is unknown whether oxytocin exhibited effects at the neuronal level, which was outside of the specific task examined. In the same randomized, double-blind, placebo-controlled, within-subject cross-over clinical trial in which a single dose of intranasal oxytocin (24 IU) was administered to 40 men with high-functioning autism spectrum disorder (UMIN000002241/000004393), we measured N-acetylaspartate (NAA) levels, a marker for neuronal energy demand, in the vmPFC using (1)H-magnetic resonance spectroscopy ((1)H-MRS). The differences in the NAA levels between the oxytocin and placebo sessions were associated with oxytocin-induced fMRI signal changes in the vmPFC. The oxytocin-induced increases in the fMRI signal could be predicted by the NAA differences between the oxytocin and placebo sessions (P=0.002), an effect that remained after controlling for variability in the time between the fMRI and (1)H-MRS scans (P=0.006) and the order of administration of oxytocin and placebo (P=0.001). Furthermore, path analysis showed that the NAA differences in the vmPFC triggered increases in the task-dependent fMRI signals in the vmPFC, which consequently led to improvements in the socio-communication difficulties associated with autism. The present study suggests that the beneficial effects of oxytocin are not limited to the autistic behavior elicited by our psychological task, but may generalize to other autistic behavioral problems associated with the vmPFC.

Field-induced quantum criticality and universal temperature dependence of the magnetization of a spin-1/2 heisenberg chain

High-precision dc magnetization measurements have been made on Cu(C4H4N2) (NO3)2 in magnetic fields up to 14.7 T, slightly above the saturation field Hs=13.97  T, in the temperature range from 0.08 to 15 K. The magnetization curve and differential susceptibility at the lowest temperature show excellent agreement with exact theoretical results for the spin-1/2 Heisenberg antiferromagnet in one dimension. A broad peak is observed in magnetization measured as a function of temperature, signaling a crossover to a low-temperature Tomonaga-Luttinger-liquid regime. With an increasing field, the peak moves gradually to lower temperatures, compressing the regime, and, at Hs, the magnetization exhibits a strong upturn. This quantum critical behavior of the magnetization and that of the specific heat withstand quantitative tests against theory, demonstrating that the material is a practically perfect one-dimensional spin-1/2 Heisenberg antiferromagnet.

Amelogenins as potential buffers during secretory-stage amelogenesis

Amelogenins are the most abundant protein species in forming dental enamel, taken to regulate crystal shape and crystal growth. Unprotonated amelogenins can bind protons, suggesting that amelogenins could regulate the pH in enamel in situ. We hypothesized that without amelogenins the enamel would acidify unless ameloblasts were buffered by alternative ways. To investigate this, we measured the mineral and chloride content in incisor enamel of amelogenin-knockout (AmelX(-/-)) mice and determined the pH of enamel by staining with methyl-red. Ameloblasts were immunostained for anion exchanger-2 (Ae2), a transmembrane pH regulator sensitive for acid that secretes bicarbonate in exchange for chloride. The enamel of AmelX(-/-) mice was 10-fold thinner, mineralized in the secretory stage 1.8-fold more than wild-type enamel and containing less chloride (suggesting more bicarbonate secretion). Enamel of AmelX(-/-) mice stained with methyl-red contained no acidic bands in the maturation stage as seen in wild-type enamel. Secretory ameloblasts of AmelX(-/-) mice, but not wild-type mice, were immunopositive for Ae2, and stained more intensely in the maturation stage compared with wild-type mice. Exposure of AmelX(-/-) mice to fluoride enhanced the mineral content in the secretory stage, lowered chloride, and intensified Ae2 immunostaining in the enamel organ in comparison with non-fluorotic mutant teeth. The results suggest that unprotonated amelogenins may regulate the pH of forming enamel in situ. Without amelogenins, Ae2 could compensate for the pH drop associated with crystal formation.

Determination of local atomic displacements in CeO(1-x)F(x)BiS2 system

We have used Bi and Ce L3-edges extended x-ray absorption fine structure measurements to study local structure of CeO(1-x)F(x)BiS2 system as a function of F-substitution. The local structure of both BiS2 active layer and CeO1-xFx spacer layer changes systematically. The in-plane Bi-S1 distance decreases (ΔRmax ∼ 0.08 Å) and the out-of-plane Bi-S2 distance increases (ΔRmax ∼ 0.12 Å) with increasing F-content. On the other hand, the Ce-O/F distance increases (ΔRmax ∼ 0.2 Å) with a concomitant decrease of the Ce-S2 distance (ΔRmax ∼ 0.15 Å). Interestingly, the Bi-S1 distance is characterized by a large disorder that increases with F-content. The results provide useful information on the local atomic displacements in CeO(1-x)F(x)BiS2, that should be important for the understanding of the coexistence of superconductivity and low temperature ferromagnetism in this system.

Pressure-dependent magnetization and magnetoresistivity studies on tetragonal FeS (mackinawite): revealing its intrinsic metallic character

The transport and magnetic properties of the tetragonal Fe[Formula: see text]S were investigated using magnetoresistivity and magnetization within [Formula: see text] K, [Formula: see text] 70 kOe and [Formula: see text] 3.0 GPa. In addition, room-temperature x-ray diffraction and photoelectron spectroscopy were also applied. In contrast to previously reported nonmetallic character, Fe[Formula: see text]S is intrinsically metallic but due to a presence of a weak localization such metallic character is not exhibited below room temperature. An applied pressure reduces strongly this additional resistive contribution and as such enhances the temperature range of the metallic character which, for ∼3 GPa, is evident down to 75 K. The absence of superconductivity as well as the mechanism behind the weak localization will be discussed.

Amplification of PVT-1 is involved in poor prognosis via apoptosis inhibition in colorectal cancers

Background:

We previously conducted gene expression microarray analyses to identify novel indicators for colorectal cancer (CRC) metastasis and prognosis from which we identified PVT-1 as a candidate gene. PVT-1, which encodes a long noncoding RNA, mapped to chromosome 8q24 whose copy-number amplification is one of the most frequent events in a wide variety of malignant diseases. However, PVT-1 molecular mechanism of action remains unclear.

Methods:

We conducted cell proliferation and invasion assays using colorectal cancer cell lines transfected with PVT-1siRNA or negative control siRNA. Gene expression microarray analyses on these cell lines were also carried out to investigate the molecular function of PVT-1. Further, we investigated the impact of PVT-1 expression on the prognosis of 164 colorectal cancer patients by qRT–PCR.

Results:

CRC cells transfected with PVT-1 siRNA exhibited significant loss of their proliferation and invasion capabilities. In these cells, the TGF-β signalling pathway and apoptotic signals were significantly activated. In addition, univariate and multivariate analysis revealed that PVT-1 expression level was an independent risk factor for overall survival of colorectal cancer patients.

Conclusion:

PVT-1, which maps to 8q24, generates antiapoptotic activity in CRC, and abnormal expression of PVT-1 was a prognostic indicator for CRC patients.

Low-temperature low-field phases of the pyrochlore quantum magnet Tb2Ti2O7

By means of ac magnetic-susceptibility measurements, we find evidence for a new magnetic phase of Tb2Ti2O7 below about 140 mK in zero magnetic field. In magnetic fields parallel to [111], this phase is characterized by frequency- and amplitude-dependent susceptibility and extremely slow spin dynamics. In the zero-temperature limit, it extends to about 67 mT (the internal field H(int)≃52  mT), at which it makes transition to another phase. The field dependence of the susceptibility of this second phase, which extends to about 0.60 T (H(int)≃0.54  T) in the zero-temperature limit, indicates the presence of a weak magnetization plateau below about 50 mK, as has been predicted by a single-tetrahedron four-spin model, suggesting that the second phase is a quantum kagome ice.

Successive phase transitions and extended spin-excitation continuum in the S=1/2 triangular-lattice antiferromagnet Ba3CoSb2O9

Using magnetic, thermal, and neutron measurements on single-crystal samples, we show that Ba3CoSb2O9 is a spin-1/2 triangular-lattice antiferromagnet with the c axis as the magnetic easy axis and two magnetic phase transitions bracketing an intermediate up-up-down phase in magnetic field applied along the c axis. A pronounced extensive neutron-scattering continuum above spin-wave excitations, observed below T(N), implies that the system is in close proximity to one of two spin-liquid states that have been predicted for a 2D triangular lattice.

Electronic properties of FeSe(1-x)Te(x) probed by x-ray emission and absorption spectroscopy

The electronic structure of FeSe(1-x)Te(x) chalcogenide superconductors has been studied by x-ray emission (XES) and x-ray absorption (XAS) as a function of Te substitution. The Fe Kβ XES spectra reveal a relatively low spin state for Fe in FeSe(1-x)Te(x) superconductors, persisting in the whole range of Te substitution. The Fe K-edge high-resolution XAS shows systematic spectral changes due to the evolving hybridization between the Fe 3d (4p) and chalcogen p (d) orbitals. The resonant inelastic x-ray scattering (RIXS) spectra hardly show any feature except the one due to charge transfer from occupied to unoccupied bands, that changes substantially from FeSe to FeTe. The results provide important information on the electronic states and their evolution in the FeSe(1-x)Te(x) chalcogenides.

Isolation of highly purified rat cerebral lysosomes using percoll gradients with a variety of calcium concentrations

We were able to isolate a lysosomal fraction from rat brain which had a higher degree of purity than in previous studies with good recovery. This has been made possible by using percoll gradients following the swelling of mitochondria in the presence of calcium which would eliminate contamination from small amounts of mitochondria. By using percoll density gradient centrifugation after the swelling of mitochondria in the presence of calcium, cerebral lysosomes were purified 312-fold with the recovery of approximately 22 %, which is the highest reported for any cerebral lysosomal preparation. The most effective procedure for the separation was achieved by using 1.25 mM calcium incubation with post nuclear fraction. As brain lysosomes may play a major role not only in degrading macromolecules but also in their transport to the deposition site, obtaining purified rat cerebral lysosomes represents an important step in the study of the generation of macromolecules which accumulate in the brain.

The clinicopathological significance of REIC expression in colorectal carcinomas

REIC is down-regulated in immortalized cell lines compared with the parental normal counterparts, and could inhibit colony formation, tumor growth and induce apoptosis. Here, its expression was examined by immunohistochemistry on tissue microarray containing colorectal non-neoplastic mucosa (NNM), adenoma and adenocarcinoma. Colorectal carcinoma tissue and cell lines were studied for REIC expression or its secretory level by Western blot, RT-PCR or enzyme-linked immunosorbent assay (ELISA). The results demonstrated that REIC was differentially expressed in Colo201, Colo205, DLD-1, HCT-15, HCT-116, HT-29, KM-12, SW480, SW620, and WiDr with its secretion concentration less than 300 pg/mL. Carcinomas showed statistically lower REIC expression than matched NNM with no difference for protein content. Immunohistochemically, REIC expression was significantly decreased from NNM, adenoma to adenocarcinoma (p<0.05). REIC expression was negatively correlated with depth of invasion, TNM staging, dedifferentiation, Capase-3 and nuclear inhibitor of growth 5 (ING5) expression (p<0.05), while not with age, sex, tumor size, lymphatic or venous invasion, or lymph node metastasis (p>0.05). Kaplan-Meier analysis indicated that REIC expression was not associated with the prognosis of colorectal carcinomas (p>0.05). Cox's analysis demonstrated that lymphatic and venous invasion, lymph node metastasis, and UICC staging were independent prognostic factors for carcinoma (p<0.05). Our study indicated that down-regulated REIC expression might play an important role in colorectal adenoma-adenocarcinoma sequence and subsequent progression. Aberrant REIC expression might be employed as a good marker of pathogenesis and development of colorectal carcinomas.

Pharmacotherapeutic determinants for QTc interval prolongation in Japanese patients with mood disorder

An increased incidence of sudden death has been observed among patients treated with antidepressants. A prolonged QTc interval is a known prognostic factor for fatal arrhythmia, and several studies have shown that the use of antidepressants can cause a prolonged QTc interval. However, few studies, especially in Japan, have compared the effects of multiple drugs on QTc interval or examined dose relationships in a clinical setting.We compared the effects of antidepressants on QT interval, corrected to QTc by Bazett's formula, in 729 Japanese patients who were diagnosed with mood disorder.Using stepwise multiple linear regression analysis, we found that the use of tricyclic antidepressants (P<0.01) and concomitant use of antipsychotics (P<0.05), as well as advanced age and being female (known factors for prolonged QTc interval; both P<0.01), significantly prolonged the QTc interval. Analysis of individual antidepressants also revealed that the use of clomipramine (P<0.01) and amitriptyline (P<0.05) significantly prolonged the QTc interval.Our results reveal that tricyclic antidepressants, especially clomipramine and amitriptyline, confer a risk of prolonged QTc interval in a dose-dependent manner. The selective serotonin reuptake inhibitors investigated (fluvoxamine, paroxetine, sertraline) were not indicated as risk factors for QTc prolongation.

Large local disorder in superconducting K(0.8)Fe(1.6)Se2 studied by extended x-ray absorption fine structure

We have measured the local structure of superconducting K(0.8)Fe(1.6)Se(2) chalcogenide (T(c) = 31.8 K) by temperature dependent polarized extended x-ray absorption fine structure (EXAFS) at the Fe and Se K-edges. We find that the system is characterized by a large local disorder. The Fe-Se and Fe-Fe distances are found to be shorter than the distances measured by diffraction, while the corresponding mean square relative displacements reveal large Fe-site disorder and relatively large c-axis disorder. The local force constant for the Fe-Se bondlength (k ~ 5.8 eV Å(-2)) is similar to the one found in the binary FeSe superconductor, however, the Fe-Fe bondlength appears to be flexible (k ~ 2.1 eV Å(-2)) in comparison to the binary FeSe (k ~ 3.5 eV Å(-2)), an indication of partly relaxed Fe-Fe networks in K(0.8)Fe(1.6)Se(2). The results suggest a glassy nature for the title system, with the superconductivity being similar to that in the granular materials.

Wilson ratio of a Tomonaga-Luttinger liquid in a spin-1/2 Heisenberg ladder

Using micromechanical force magnetometry, we have measured the magnetization of the strong-leg spin-1/2 ladder compound (C(7)H(10)N)(2)CuBr(2) at temperatures down to 45 mK. Low-temperature magnetic susceptibility as a function of field exhibits a maximum near the critical field H(c) at which the magnon gap vanishes, as expected for a gapped one-dimensional antiferromagnet. Above H(c) a clear minimum appears in the magnetization as a function of temperature, as predicted by theory. In this field region, the susceptibility in conjunction with our specific-heat data yields the Wilson ratio R(W). The result supports the relation R(W)=4K, where K is the Tomonaga-Luttinger-liquid parameter.

Random alloy-like local structure of Fe(Se, S)(1-x)Te(x) superconductors revealed by extended x-ray absorption fine structure

The local structure of Fe(Se, S)(1-x)Te(x) ternary (11-type) chalcogenides has been studied by temperature dependent Fe K-edge extended x-ray absorption fine structure measurements. We find that the Fe-Se and Fe-Te distances in ternary FeSe(1-x)Te(x) are closer to the respective distances in the binary systems, revealing significant divergence of the local structure from the average one. The mean square relative displacements show a systematic change with Te content, consistent with bond relaxation in the inhomogeneous ternary phases. Also, the Fe-Te and Fe-S distances in the FeS(0.2)Te(0.8) ternary system are found to be different in the crystallographically homogeneous structure. The observed features are characteristic of ternary random alloys, suggesting that a proper consideration should be given to the atomic distribution for describing the complex electronic structure of these multi-band Fe-based chalcogenides.

Note: Relaxation heat capacity measurements at low temperatures: dealing with nuclear contribution

Nuclear heat capacity is a serious obstacle in low temperature heat capacity measurements by a relaxation technique. However, this method allows an experimenter to measure the electronic heat capacity directly, if the ratio of electronic heat capacity to the conductance of the calorimeter is sufficiently small in comparison with nuclear-spin relaxation times. This is because the initial rate of a temperature decay is always determined by the electronic degrees of freedom and does not depend on nuclear degrees of freedom. This previously unrecognized feature is clearly demonstrated through measurements of Cu in external magnetic fields.

A study of the electronic structure of FeSe(1-x)Te(x) chalcogenides by Fe and Se K-edge x-ray absorption near edge structure measurements

Fe K-edge and Se K-edge x-ray absorption near edge structure (XANES) measurements are used to study the FeSe(1 - x)Te(x) electronic structure of chalcogenides. An intense Fe K-edge pre-edge peak due to Fe 1s --> 3d (and admixed Se/Te p states) is observed, showing substantial change with Te substitution and x-ray polarization. The main white line peak in the Se K-edge XANES due to Se 1s --> 4p transition appears similar to the one expected for Se(2-) systems and changes with Te substitution. Polarization dependence reveals that unoccupied Se orbitals near the Fermi level have predominant p(x, y) character. The results provide key information on the hybridization of Fe 3d and chalcogen p states in the Fe-based chalcogenide superconductors.

Field-induced Tomonaga-Luttinger liquid phase of a two-leg spin-1/2 ladder with strong leg interactions

We study the magnetic-field-induced quantum phase transition from a gapped quantum phase that has no magnetic long-range order into a gapless phase in the spin-1/2 ladder compound bis(2,3-dimethylpyridinium) tetrabromocuprate (DIMPY). At temperatures below about 1 K, the specific heat in the gapless phase attains an asymptotic linear temperature dependence, characteristic of a Tomonaga-Luttinger liquid. Inelastic neutron scattering and the specific heat measurements in both phases are in good agreement with theoretical calculations, demonstrating that DIMPY is the first model material for an S=1/2 two-leg spin ladder in the strong-leg regime.