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The frictional velocity dependence and healing behavior of subduction fault zones play key roles in the nucleation of stick‐slip instabilities at convergent margins. Diagenetic to low‐grade metamorphic processes such as pressure solution are proposed to be responsible for the change in frictional properties of fault materials along plate interfaces; pressure solution also likely contributes to the acceleration of healing according to previous studies. Here, we report friction studies for temperatures of 20–100°C and normal stresses from 20 to 125 MPa on samples collected from ancient subduction fault zones, the Lower Mugi and Makimine mélanges of the Cretaceous Shimanto belt. The two mélanges correspond to the updip and downdip limits of the seismogenic zone and include deformation features that indicate lower and higher degrees of pressure solution. Our data show that the Lower Mugi mélange exhibits velocity‐weakening to velocity‐neutral frictional behavior under low normal stress and that the Makimine mélange sample shows velocity‐strengthening behavior under high normal stress. We suggest that mineralogical changes due to diagenesis and metamorphism influence fault slip behavior. We measure frictional healing in slide‐hold‐slide experiments for the Lower Mugi mélange sample and document the role of pressure solution in fault healing. Our results show that frictional healing increases at higher temperatures. The microstructures related to pressure solution found in the post‐experimental gouges support the idea that the enhanced healing is related to pressure solution. Plain Language Summary: Investigating the mechanical properties of rock materials in plate boundary faults is crucial for the understanding of subduction zone earthquakes. The nucleation of earthquakes along the plate boundary occurs in a zone where friction drops during slip and fault strength rebuilds after an earthquake. The mechanical properties of fault materials in this zone are likely influenced by local diffusion of mobile elements during the interseismic period. Here, we perform friction experiments using two samples of ancient plate boundary faults that were near the updip and downdip limits of the zone, respectively. The first set of experiments reveals a variation in frictional response to slip under an experimental setup analogous to subduction zone conditions. Variation in the magnitude of interseismic pressure solution strain preserved in the samples is likely the cause of varying responses that lead to the nucleation and cessation of earthquakes. We conduct another series of experiments under varying hydrothermal conditions that reveal a faster restrengthening of the fault material at elevated temperatures. This is likely related to the temperature dependence of pressure solution, which is found to be an operative deformation mechanism based on the examination of post‐experimental materials. Key Points: Mélanges bounding the upper and lower limits of the seismogenic zone show changes in frictional velocity‐dependence with normal stressMicrostructures of the sheared samples suggest that temperature dependence of healing occurs via diffusive mass transferThermally‐activated deformation mechanisms can modulate frictional velocity‐dependence and healing behavior of plate boundary faults [ABSTRACT FROM AUTHOR]

Tectonic mélanges, characterized by conditions reflective of modern subduction fault zones, preserve mineral veins formed through mass transfer, a mechanism influencing the slip behavior of subduction megathrusts. In this study, we apply secondary ion mass spectrometry quartz‐calcite oxygen isotope thermometry and clumped isotope thermometry to examine the temperatures of vein formations in six mélange units in the Cretaceous Shimanto belt and one mélange in the Kodiak accretionary prism. Calcite in the veins exhibits δ13CPDB values ranging from −17.2‰ to −6.8‰, indicative of a carbon source mixing with sedimentary carbonate and organic matter. δ18OSMOW values of calcite range from +11.1‰ to +17.2‰; quartz yields δ18OSMOW values of +14.9‰ to +21.7‰. Oxygen isotopic signatures in minerals reveal that most vein‐forming fluids are significantly affected by rock buffering, while some retain isotopic compositions of seawater and meteoric water. Temperature estimates, derived from both thermometers, fall within the range of 100–250°C. Notably, vein temperatures remain constant across diverse vein types and mélange units with distinct maximum temperatures. The combined temperature records and fluid isotopic compositions imply vein formations at shallower depths linked to the incorporation of seawater, meteoric water, and fluid released from early dehydration reactions. At greater depths, vein formations are associated with fluid released from clay dehydration and long‐distance fluid flow. Reduced vein formations between 250 and 350°C may correlate with a shift to fluid‐unsaturated conditions resulting from clay hydration reactions. Our study highlights potential mechanical and hydraulic variations within the thermal conditions of 100–350°C along the plate boundary driven by fluid‐mineral interactions. Plain Language Summary: Temperature influences the processes responsible for triggering earthquakes at subduction zones. This inference is supported by the observed concentration of seismic activities within a specific temperature range along the plate interface. To investigate the topic, we examine a distinctive rock type known as tectonic mélanges, which has undergone subduction in the past and has since been exposed. These mélanges contain mineral veins formed through the movement of materials; a factor that has shown correlation with the occurrence of earthquakes at subduction zones. To determine the temperatures at which the mechanism operates, leading to the formation of the veins, we employ two methodologies: quartz‐calcite oxygen isotope thermometry and clumped isotope thermometry. Our findings indicate that, regardless of the geographical locations or the types of veins, they formed within a temperature range of 100–250°C. This consistency implies the existence of a consistent depth range within subduction zones, where fluids are predominantly present, facilitating material movement and consequently, the development of these mineral veins. Key Points: Quartz‐calcite veins in ancient accretionary prisms record temperatures of 100–250°C, implying a fluid‐rich zone along plate interfacesFluid isotopic compositions suggest rock‐buffered fluids as major vein‐forming fluids derived from the dehydration of host rocksReduced vein formation, along with clay hydration at 250–350°C, may cause a shift in hydrogeology and mechanics of subduction fault zones [ABSTRACT FROM AUTHOR]

Estimating interseismic deformation in subduction fault zones can offer insights into the frequency and magnitude of megathrust earthquakes. Diffusive mass transfer is a significant mechanism of strain during interseismic periods along the plate interface, observed through the pervasive scaly fabrics and mineral veins in tectonic mélanges of ancient accretionary prisms. The dissolution of fluid‐mobile elements (e.g., Si and Large‐Ion Lithophile Elements) along scaly folia and subsequent reprecipitation as veins lead to the enrichment of fluid‐immobile elements (e.g., Ti and High Field Strength Elements) in scaly fabrics. The kinetics of dissolution‐precipitation is temperature‐dependent, suggesting depth‐dependent mass transfer along subduction interfaces. Here, we evaluate the magnitudes of volume strain in a suite of mélange samples that span peak metamorphic temperatures of 130–340°C. Micro‐chemical analysis shows that the depletion of fluid‐mobile elements and enrichment of fluid‐immobile elements in scaly fabrics increases with temperature. Assuming the conservation of Ti, we apply mass balance constraints to calculate the volumetric strain in scaly fabrics. Results indicate average volumetric strain of 28% and 95% in the individual scaly fabrics of the Lower Mugi and Makimine mélanges in Japan, which record temperatures near the updip and downdip isotherms bounding the seismogenic zone, respectively. To determine the total volume strain within an area of interest, we integrate the amount of volume loss along individual microstructures across the network using image analyses, which ranges from 3% to 14% for the mélanges. Our approach demonstrates the potential to fully describe the deformation related to mass transfer by connecting characterization in different scales with geochemical analyses. Plain Language Summary: Estimating how subduction fault zones deform between major earthquakes provides information about the frequency and magnitude of those earthquakes. One significant way in which deformation occurs is through the movement of substances within fault zones. We observe the evidence in rocks from ancient subduction fault zones, where substances in specific rock fabrics dissolve in fluids and reprecipitate in mineral‐filled cracks. The process by which material redistributes at depth within subduction fault zones is dependent on temperature; therefore, we analyze a collection of rock samples that experienced varying temperatures. Through the examination of rock chemistry, we discover that elements carried by fluid are depleted in specific rock fabrics, while other immobile elements become enriched depending on temperature. We combine the chemistry with mathematical calculations to estimate the amount of deformation in terms of changes in rock volume. Our results reveal variations in volume loss in fabrics of rocks that experienced the lowest and highest temperatures among our samples. To obtain a comprehensive understanding of the deformation in our area of interest, we integrate the results with an analysis of rock images. Our study demonstrates how we can gain insights into the deformation occurring during these periods by combining different analytical approaches. Key Points: Mass‐balance analysis quantifies strain in a microstructure. Coupling with image analysis integrates strain over the area of interestDegrees of mass transfer vary with temperature observed in tectonic mélangesSingle scaly fabrics exhibit >60% average volume loss, while mélanges show <20% total volume strain [ABSTRACT FROM AUTHOR]

The empirical relationship between the porosity and P‐wave velocity is a useful tool for probing large‐scale underground physical properties and stress states based on P‐wave velocity structures acquired by seismic surveys. In this study, the porosity‐velocity curves were examined using local core sample and logging datasets acquired along the Kumano transect in the Nankai Trough, Southwest Japan. We tested Hashimoto et al.'s (2010) hypothesis that slope apron and accreted sediments have different relationships. Our advantage is using a large amount of logging and core data obtained at multiple sites in the Nankai Trough under various geological conditions, from the incoming oceanic plate to the inner wedge. We identified multiple types of porosity – P‐wave velocity relationships: 1) The first type agrees with the low‐velocity model in the global empirical relation of Erickson and Jarrard 1998), which is observed at lithostatic stress state condition (incoming upper Shikoku basin and slope sediments), 2) The second type consistent with high‐velocity models of the global empirical relation observed at compressive stress state condition (accreted sediments), which have a higher velocity and larger dependence on the porosity than the first type with the same porosity, and 3) The third type for incoming sediments with high smectite content has lower velocity than the first type. Based on our results, the transition between the first and second porosity – velocity relationships occurs in the prism toe, implying that compressive stress due to subduction controls acoustic properties and the lithification process of these sediments. Plain Language Summary: Physical properties of rocks in subduction zones are important factors controlling genesis of earthquakes. Among many kinds of physical properties, this study focuses on the relationship between porosity and P‐wave velocity at the Nankai Trough, Southwest Japan. As this relationship is affected by how the soft sediments are lithified through the subduction process, it has been studied frequently to understand physical properties and stress states of geological formations around plate boundary faults. This study compiles P‐wave velocity datasets acquired by scientific drilling projects in offshore regions, as well as porosity datasets. We tested the hypothesis proposed by a previous study that there are two types of the relationships between the two quantities. We find these two types are consistent with the global empirical relationships observed at lithostatic and compressive stress states respectively. The former includes sediments on the oceanic plate before subduction and slope apron sediments. The latter are sediments accreted toward the Japan arc. We also find that the transition from the former to the latter occurs in the sediments at the tip of accretionary prism. This suggests that compressive stress state due to subduction plays an important role in controlling the acoustic properties of sediments. Key Points: Porosity and P‐wave velocity data were compiled to investigate their relationships at the Kumano transect in the Nankai TroughAccreted sediments have higher P‐wave velocity compared with incoming and slope apron sediments with the same porosityThe stress state in the accretionary prism might be a factor controlling the porosity – P‐wave velocity relationships of sediments [ABSTRACT FROM AUTHOR]

The effect of low-carbohydrate diet (LCD) on body composition, especially fat mass, in obese individuals remains to be elucidated. We performed a meta-analysis to provide quantitative summary estimates of the mean change of body weight (kg) and fat mass (kg) in LCD comparing to those in control diet. Literature searches were performed using EMBASE, MEDLINE and Cochrane Library until Dec 2014. Fourteen randomized controlled studies were included in this meta-analysis. Eight studies including very LCD (50 g carbohydrate or 10% calorie from carbohydrate) and seven studies including mild LCD (about 40% calorie from carbohydrate). Meta-analysis carried out on data of 1416 obese individuals, showed that LCD was associated with decrease in body weight (−0.70 kg [95% CI −1.07/−0.33]) or fat mass (−0.77 kg [−1.55/−0.32]). Subgroup meta-analysis of studies in over 12 months suggested that LCD was not associated with decrease in body weight (−0.44 kg [−0.94/0.07]), but LCD was associated with decrease in fat mass (−0.57 kg [−1.05/−0.09]). In addition, very LCD was associated with decrease in fat mass (−0.97 kg [−1.50/−0.44]), but mild LCD was not associated with decrease in fat mass (−0.43 kg [−1.15/0.33]). LCD, especially very LCD, might be effective for decrease in fat mass in obese individuals. © 2016 World Obesity [ABSTRACT FROM AUTHOR]

Elevation of the posterior part of the tongue is important for normal deglutition and speech. The purpose of this study was to develop a new surface electromyography (EMG) method to non-invasively and objectively evaluate activity in the muscles that control lifting movement in the posterior tongue. Neck surface EMG (N-EMG) was recorded using differential surface electrodes placed on the neck, 1 cm posterior to the posterior border of the mylohyoid muscle on a line orthogonal to the lower border of the mandible. Experiment 1: Three healthy volunteers (three men, mean age 37·7 years) participated in an evaluation of detection method of the posterior tongue lifting up movement. EMG recordings from the masseter, temporalis and submental muscles and N-EMG revealed that i) N-EMG was not affected by masseter muscle EMG and ii) N-EMG activity was not observed during simple jaw opening and tongue protrusion, revealing the functional difference between submental surface EMG and N-EMG. Experiment 2: Seven healthy volunteers (six men and one woman, mean age 27·9 years) participated in a quantitative evaluation of muscle activity. Tongue-lifting tasks were perfor-med, exerting a prescribed force of 20, 50, 100 and 150 gf with visual feedback. For all subjects, a significant linear relationship was observed bet-ween the tongue-lifting force and N-EMG activity ( P < 0·01). These findings indicate that N-EMG can be used to quantify the force of posterior tongue lifting and could be useful to evaluate the effect of tongue rehabilitation in future studies. [ABSTRACT FROM AUTHOR]

Aims A close association between heart rate-corrected QT interval ( QTc) and albuminuria in people with Type 2 diabetes has been reported in cross sectional studies. The aim of this study was to evaluate the relationship between QTc and change in urine albumin excretion ( UAE) or progression of albuminuria in people with Type 2 diabetes. Methods We measured QTc in 251 consecutive people at baseline. We performed a 5-year follow-up cohort study to assess the relationship between QTc and change in UAE, defined as an increase of UAE/follow-up duration (year), or progression of albuminuria, defined as an increase in the category of diabetic nephropathy. Results During follow-up, 23 of 151 people with normoalbuminuria and 13 of 73 people with microalbuminuria at baseline had progression of albuminuria. Multiple regression analysis demonstrated that QTc was independently associated with change in UAE (β = 0.176, P = 0.0104 ). Logistic regression analyses showed that QTc was a risk marker for progression of albuminuria [odds ratio per 0.01-s increase in QTc 1.35, 95% confidence interval ( CI) 1.11-1.66, P = 0.0024] after adjusting for confounders. According to the receiver operator characteristic ( ROC) analysis, the optimal cut-off point of QTc for progression of albuminuria was 0.418 s [area under the ROC curve 0.75 (95% CI 0.66-0.82), sensitivity = 0.86, specificity = 0.56, P < 0.0001]. Conclusions Heart rate-corrected QT interval could be a novel risk marker for progression of albuminuria in people with Type 2 diabetes. [ABSTRACT FROM AUTHOR]

Aims Abnormalities in the imprinted locus on chromosome 6q24 are the most common causes of transient neonatal diabetes mellitus (6q24-related transient neonatal diabetes). 6q24-Related transient neonatal diabetes is characterized by the patient being small-for-gestational age, diabetes mellitus at birth, spontaneous remission within the first few months and frequent recurrence of diabetes after childhood. However, it is not clear whether individuals with 6q24 abnormalities invariably develop transient neonatal diabetes. This study explored the possibility that 6q24 abnormalities might cause early-onset, non-autoimmune diabetes without transient neonatal diabetes. Methods The 6q24 imprinted locus was screened for abnormalities in 113 Japanese patients with early-onset, non-obese, non-autoimmune diabetes mellitus who tested negative for mutations in the common maturation-onset diabetes of the young (MODY) genes and without a history of transient neonatal diabetes. Positive patients were further analysed by combined loss of heterozygosity / comparative genomic hybridization analysis and by microsatellite analysis. Detailed clinical data were collected through the medical records of the treating hospitals. Results Three patients with paternal uniparental isodisomy of chromosome 6q24 were identified. None presented with hyperglycaemia in the neonatal period. Characteristically, these patients were born small-for-gestational age, representing 27.2% of the 11 patients whose birth weight standard deviation score (SDS) for gestational age was below −2.0. Conclusions Abnormalities in the imprinted locus on chromosome 6q24 do not necessarily cause transient neonatal diabetes. Non-penetrant 6q24-related diabetes could be an underestimated cause of early-onset, non-autoimmune diabetes in patients who are not obese and born small-for-gestational age. [ABSTRACT FROM AUTHOR]

The wave analysis of swallowing sounds has been receiving attention because the recording process is easy and non-invasive. However, up until now, an expert has been needed to visually examine the entire recorded wave to distinguish swallowing from other sounds. The purpose of this study was to establish a methodology to automatically distinguish the sound of swallowing from sound data recorded during a meal in the presence of everyday ambient sound. Seven healthy participants (mean age: 26·7 ± 1·3 years) participated in this study. A laryngeal microphone and a condenser microphone attached to the nostril were used for simultaneous recording. Recoding took place while participants were taking a meal and talking with a conversational partner. Participants were instructed to step on a foot pedal trigger switch when they swallowed, representing self-enumeration of swallowing, and also to achieve six additional noise-making tasks during the meal in a randomised manner. The automated analysis system correctly detected 342 out of the 352 self-enumerated swallowing events (sensitivity: 97·2%) and 479 out of the 503 semblable wave periods of swallowing (specificity: 95·2%). In this study, the automated detection system for swallowing sounds using a nostril microphone was able to detect the swallowing event with high sensitivity and specificity even under the conditions of daily life, thus showing potential utility in the diagnosis or screening of dysphagic patients in future studies. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the applicability of selective extraction methods in combination with solution phosphorus-31 (31P) nuclear magnetic resonance ( NMR) for the determination of organic phosphorus (Po) species in soil. Inositol hexakisphosphates ( IHP) and glucose 6-phosphate ( GP) were identified in the soil. IHP adsorbed to both soil organic matter ( SOM) and short-range order ( SRO) minerals, whereas GP adsorbed only to SOM. These results suggest that Po hosting phases are different depending on Po species. [ABSTRACT FROM AUTHOR]

We studied 40 adult patients to see if cricoid pressure affected placement of the I-gel™. In a randomised crossover design, the i-gel was placed with and without cricoid pressure, and we compared the success rate of adequate ventilation through the i-gel, time to placement and the rate of optimal position of the device between the two circumstances. Cricoid pressure significantly decreased the success rate of adequate ventilation through the i-gel (40 vs 34 patients) (p = 0.041, 95% CI for difference 4-26%), and significantly decreased the rate of the optimal position (39 vs 17 patients) (p < 0.001). The time to achieve adequate ventilation was significantly longer (p < 0.001) with cricoid pressure than without (median difference 8 s; 95% CI for median difference 3-12 s). Cricoid pressure significantly decreases the success rate of ventilation through the i-gel, but the success rate of ventilation through the i-gel is reasonably high. [ABSTRACT FROM AUTHOR]

Previously, the structure of the adult goat parotid salivary glands ( PGs) was studied. However, little information was elucidated of the juvenile ones. This study aimed to clarify the correlations between the structure of goats' PGs and the nature of food intake among milk-suckling kids ( MSKs) and diet-fed goats ( DFGs). The secretory endpieces of the goats' PGs are of the pure serous type. The serous cells in MSKs showed apical accumulation of numerous secretory granules ( SGs) of smaller size and of more intense positive periodic acid-Schiff reaction. Ultrastructurally, most of the SGs in the DFGs contained peripherally located inclusions that showed dense reaction products for acid phosphatase. In MSKs, the PGs showed less-developed basal infoldings, sparseness of the inter-cellular inter-digitations, fewer inter-cellular canaliculi and microvilli and also less-developed myoepithelial cells with fewer and shorter cytoplasmic processes. In conclusion, the less-developed membrane specializations and myoepithelial cells, as well as the accumulated SGs in the PGs of MSKs, suggest that it secretes less saliva with a little secretory activity than that of DFGs, which may be correlated with the reduced masticatory activity. [ABSTRACT FROM AUTHOR]

Semipolar {11-22} plane GaN layer was grown using a SiN x intermediate layer by hydride vapor phase epitaxy (HVPE). By optimizing the deposition time of the SiN x intermediate layer, the dislocation density decreased compared to that of a conventional {11-22} GaN layer. The reduction in the dislocation density was due to three dimensional regrowth of the {11-22} GaN layer at the interface. However, basal plane stacking faults (BSFs) were increased by use of the SiN x intermediate layer, and with increasing the SiN x deposition time. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Because food texture is regarded as an important factor for smooth deglutition, identification of objective parameters that could provide a basis for food texture selection for elderly or dysphagic patients is of great importance. We aimed to develop an objective evaluation method of mastication using a mixed test food comprising foodstuffs, simulating daily dietary life. The particle size distribution (>2 mm in diameter) in a bolus was analysed using a digital image under dark-field illumination. Ten female participants (mean age ± s.d., 27·6 ± 2·6 years) masticated a mixed test food comprising prescribed amounts of rice, sausage, hard omelette, raw cabbage and raw cucumber with 100%, 75%, 50% and 25% of the number of their masticatory strokes. A single set of coefficient thresholds of 0·10 for the homogeneity index and 1·62 for the particle size index showed excellent discrimination of deficient masticatory conditions with high sensitivity (0·90) and specificity (0·77). Based on the results of this study, normal mastication was discriminated from deficient masticatory conditions using a large particle analysis of mixed foodstuffs, thus showing the possibility of future application of this method for objective decision-making regarding the properties of meals served to dysphagic patients. [ABSTRACT FROM AUTHOR]

Hepatocyte nuclear factor (HNF) 4α, a transcription factor of the nuclear hormone receptor family, is generally expressed in some endoderm-derived epithelial tissues such as hepatocytes. In mice, an alternative promoter referred to as the P2 promoter is located upstream from the P1 promoter, resulting in the transcription of at least nine isoforms. In this study, we investigated the expression of Hnf4α in adult and embryonic mouse tissues, paying special attention to the developing metanephros by using immunohistochemistry and reverse transcriptase-polymerase chain reaction for the detection of P1 and/or P2 promoter-derived products. In adult mouse tissues, the kidney was the only organ expressing Hnf4α controlled only by the P1 promoter, and HNF4α was detected in the nuclei of epithelial cells in the proximal tubules, but not in other components of the nephron. In the metanephros, HNF4α was detected first at the epithelial cell nuclei in part of the comma-shaped body, distributed widely throughout the developing nephron and finally restricted to the proximal tubules. Interestingly, it was noted that Hnf4α mRNAs from stomach, pancreas and kidney tissues in embryonic periods were transcribed by both promoters. Immunohistochemistry for HNF4α and HNF1α revealed that both factors involved the same network of transcription factors, giving the impression that HNF4α was upstream of HNF1α. [ABSTRACT FROM AUTHOR]

The role of prostaglandins (PGs) on mechanical scratching-induced cutaneous barrier disruption in mice was investigated by comparing the observed effects of arachidonic acid (AA) application. Scratching of the mouse skin with a stainless-steel wire brush (mechanical scratching) was associated with significant, scratch-count-dependent elevation of the transepidermal water loss (TEWL) and skin PG levels (especially PGD2 and PGE2). Histological evidence of inflammation (crusta, acanthosis and neutrophilic infiltration) in the skin also became evident 24 h after mechanical scratching. On the other hand, while topical application of 0.1% AA to the mouse skin also increased the skin PG levels, but did not produce any increase of TEWL or histological evidence of inflammation in the skin. Topical application of cyclooxygenase inhibitors (indomethacin, piroxicam, aspirin, diclofenac and ketoprofen) decreased the spontaneous recovery rates from cutaneous barrier disruption. These results suggest that the elevation of cutaneous PG production induced by mechanical scratching is involved in the repair of the skin damage caused by the scratching. [ABSTRACT FROM AUTHOR]

In MRL mice aged more than 1 year, but not in C57BL/6 mice, ovaries had grossly visible cysts presenting unilaterally or bilaterally. Postnatally, all MRL mice developed ovarian cysts by 8 months of age. Observations by light microscopy, including lectin histochemistry, indicated that the cysts sometimes included papillomatous tissues located at the hilar region and were similar to the rete ovarii system, but not to follicles. Two types of epithelial cells, ciliated and non-ciliated, were arranged on the cysts, in which both cell types had many microvilli projecting in various directions and random ramifications in the cystic lumen. These characteristics suggest that ovarian cysts developing in MRL mice originate mostly from the rete ovarii. Cysts derived from the rete ovarii at 8 months of age were histologically detected in all C3H mice as well as MRL mice, with variable incidence in ICR, AKR, CBA/N and ddY, and none in C57L/6, DBA/2, BALB and A/J mice. However, measurement of the maximum diameters of the ovarian cysts indicated that MRL mice regularly possessed the largest cysts visible to the naked eye. This is the first report of ovarian cysts in this inbred strain, suggesting that ovarian cysts in MRL mice appear with stable incidence and development. [ABSTRACT FROM AUTHOR]

We used three types of AMN to investigate the expression profiles of melanogenesis-related genes [tyrosinase, tyrosinase-related protein-1 (TRP1), dopachrome tautomerase (TRP2), Pmel-17/gp100, P-protein, and microphthalmia-associated transcription factor (MITF)], as well as tyrosinase, TRP1, Pmel-17/gp100, and MITF proteins. Results: All melanogenesis-related genes examined in the junctional type were expressed in the basal epidermal layer. In the compound and intradermal types, mRNA for tyrosinase, TRP2, and MITF was expressed in all of the AMN cells. However, the expression of TRP1, P-protein, and Pmel-17/gp100 in the compound type and TRP1 in the intradermal type became weaker in accordance with the depth of the dermis layer, as compared to those levels in the basal to upper dermis layer. Although tyrosinase and Pmel-17/gp100 mRNA in the compound and intradermal types was expressed in the intraepidermal and dermal components, immunohistochemical staining showed that tyrosinase proteins were not detected in the lower dermis layer and Pmel-17/gp100 proteins were not detected in the dermis. Conclusions: Our results suggest that all nevus cells that constitute AMN tissue originate from melanocytes. Further, there may be differences in the transcription levels of melanogenesis-related genes as well as in their post-transcriptional regulation between nevus cells located in the basal epidermal to upper dermis layer and those in the lower dermis layer. [ABSTRACT FROM AUTHOR]

Spontaneous and 2,4,6-trinitrochlorobenzene (TNCB)-induced dermatitis models using NC/Nga mice have been recognized as animal models of atopic dermatitis. We reported that scratching behavior leads to dermatitis in a spontaneous dermatitis but not in a TNCB-induced dermatitis. Prostaglandin D2 (PGD2) suppressed the scratching behavior of NC/Nga mice, suggesting that PGD2 plays a physiological role on inhibiting pruritus. We studied whether there was a difference in skin PG contents between spontaneous and TNCB-induced dermatitis. Spontaneous dermatitis was induced by cohabitation with NC/Nga mice having severe skin lesions. TNCB-induced dermatitis was caused by applications of TNCB. PGD2, PGE2, 6keto-PGF1α, and PGF2α contents in the skin were examined using enzyme-immunoassay kits. For studying ability to produce skin PGs, PG contents were evaluated after topical treatment of arachidonic acid (AA) or mechanical scratching. In spontaneous dermatitis, PGE2, 6keto-PGF1α, and PGF2α contents increased with dermatitis, but only PGD2 did not do so. In TNCB-induced dermatitis, PGD2, PGE2, 6keto-PGF1α, and PGF2α increased. Determination of skin PG contents after AA treatment or mechanical scratching revealed that skin PGD2 production of conventional group of spontaneous dermatitis was lower than the specific pathogen-free group. It seemed that ability of skin PGD2 production was attenuated in spontaneous dermatitis. These results suggest that enhancement of scratching behavior in spontaneous dermatitis was caused by the defect of ability to produce PGD2, which plays a physiological role in inhibiting pruritus, resulting in development of dermatitis. [ABSTRACT FROM AUTHOR]

NC/Nga mice have pathological and behavioral features similar to those seen in human atopic dermatitis. There are two known dermatitis models in NC/Nga mice, one being spontaneous-induced dermatitis under conventional conditions and the other 2,4,6-trinitrochlorobenzene (TNCB)-induced allergic contact dermatitis. However, there are significant differences in time course on development of dermatitis. We studied the role of scratching behavior (sign of itch) on the development of dermatitis on spontaneous- and TNCB-induced dermatitis. We measured scratching counts, transepidermal water loss (TEWL), and skin inflammation score, under conventional conditions or by applying 5% TNCB once a week for 6 weeks in NC/Nga mice. In spontaneous-induced dermatitis, scratching counts increased with the passage of time. The scratching counts were significantly increased only 1 week after housing the mice under conventional conditions, but no changes were observed in cases of TNCB-induced dermatitis. In spontaneous-induced dermatitis, TEWL and skin-inflammation score were gradually increased, time-dependently. On the other hand, in TNCB-induced dermatitis, these dependent values rapidly increased and reached a maximum only after 24 h TNCB application. These data suggest that pathogenesis of spontaneous- and allergic contact-induced dermatitis was clearly different. It will be of major interest to identify the pruritic mediators causing profound scratching behavior and scratching-induced aggravation of inflammation in the spontaneous-induced dermatitis, as opposed to the inflammatory mediators that cause contact allergic dermatitis without major scratching. [ABSTRACT FROM AUTHOR]

Hashimoto Y, Kondo Y, Kimura G, Matsuzawa I, Sato S, Ishizaki M, Imura N, Akimoto M & Hara S (2004) Histopathology 44, 353–359 Cyclooxygenase-2 expression and relationship to tumour progression in human renal cell carcinoma Cyclooxygenase (COX), which catalyses the synthesis of prostaglandins from arachidonic acid, has two isoforms; COX-1 and COX-2. There is ample evidence to suggest an important role for COX-2 in cancer. The aim of this study was to evaluate the clinical significance of COX-2 expression and its localization in the development and progression of human renal cell carcinoma (RCC). The expression and localization of COX-2 were evaluated in human RCC tissues from 75 patients by immunohistochemistry. Immunoreactive COX-2 protein was observed in all cases of RCC, and the levels of COX-2 expression were correlated with tumour grade and pathological stage. Expression of COX-2 was higher in the granular cell subtype than in the clear cell subtype of RCC. Immunoelectron microscopy revealed that COX-2 was expressed in the nuclear membrane, rough endoplasmic reticulum, Golgi complex and mitochondrial membrane of RCC cells. COX-2 overexpression within these intracellular organelles in RCC may be associated with renal cell carcinogenesis and COX-2 may be a useful biomarker in RCC. [ABSTRACT FROM AUTHOR]

Pressure and temperature (P–T) conditions of mélange formation are estimated from fluid inclusions within “syn-mélange” veins developed in the necks of boudins of sandstone blocks in the mélange of the Shimanto accretionary complex, south-west Japan. The mélange records décollement-zone processes. P–T conditions are in the range of 81 (+15) to 235 (±18) MPa and 150 (±25) to 220 (±31)°C. Assuming a constant fluid-pressure to lithostatic-pressure ratio for each data set, we estimate a P–T gradient of between 10.0°C/km (+0.2/−1.5) (lithostatic pressure) and 4.2°C/km (+0.1/−0.9) (hydrostatic pressure) from these results. The estimated lithostatic P–T gradient is much lower than that calculated from the age of the subducting oceanic plate. The estimated P–T conditions suggest that the mélange was formed within the seismogenic zone (hypothesized from thermal modeling), although the deformation mechanism of mélange (i.e. dominant diffusive mass transfer mainly in shale matrix with minor brittle breakage mainly in sandstone blocks) does not show evidence of seismic deformation. In addition, at the time of syn-mélange vein formation, a shale matrix of mélange has injected into the vein, which indicates a ductile deformation of shale. A possible explanation for this discrepancy is that the mélange was formed during the interseismic period. [ABSTRACT FROM AUTHOR]

While it has been reported that familial Alzheimer's disease (FAD)-linked mutants of amyloid precursor protein (APP) and presenilin (PS)2 induce neuronal cytotoxicity in a manner sensitive to antioxidant and pertussis toxin (PTX), little of the mechanism for PS1-mediated neuronal cell death has been characterized. We previously found that multiple mechanisms, different in detail, underlie cytotoxicities by two FAD-linked mutants of APP, using neuronal cells with an ecdysone-controlled expression system. Here we report that this system revealed that (i) low expression of FAD-linked M146L-PS1 caused neuronal cell death, whereas that of wild-type (wt)PS1 did not; (ii) mutation-specific cytotoxicity by M146L-PS1 was sensitive to antioxidant glutathione-ethyl-ester and resistant to Ac-DEVD-CHO; (iii) cytotoxicity by higher expression of wtPS1 was resistant to both; and (iv) cytotoxicity by M146L-PS1 was inhibited by PTX. It was also highly likely that the involved superoxide-generating enzyme was nitric oxide synthase (NOS), and that the PTX-sensitive cytotoxic signal by M146L-PS1 was mediated by none of the G[sub i/o] proteins. We conclude that M146L-PS1 activates a NOS-mediated cytotoxic pathway via a novel PTX target. [ABSTRACT FROM AUTHOR]

BackgroundThe genetic background of atopic eczema might be heterogeneous and there is a possibility that immunoglobulin (Ig)E responsiveness in patients with atopic eczema is controlled separately from the development of atopic eczema. Although both interleukin (IL)-4 and the IL-4 receptor α chain have an important role for IgE production and are therefore possible candidate genes for atopy, it has not been clarified whether these genes play any roles in atopic eczema patients who have normal IgE productivity. ObjectiveWe aimed to assess whether the polymorphisms of the IL-4 gene and the IL-4 receptor α chain gene play any roles in atopic eczema patients, particularly in patients who have normal IgE productivity. MethodWe determined the genotype with regard to polymorphisms in the genes for IL-4 and the IL-4 receptor α chain (- 589C/T of IL-4; Ile50Val, Ala375Glu and Arg551Gln of IL-4 receptor α chain) in patients with atopic eczema using the fluorogenic 5′ nuclease assay. ResultsIL-4 and the IL-4 receptor α chain genotypes were not significantly associated with either total patients with atopic eczema or atopic eczema patients who had normal IgE productivity. The distribution of genotypes of IL-4–589C/T differed by the serum IgE levels in patients with atopic eczema. ConclusionThese results suggest that the polymorphisms in the IL-4 gene and the IL-4 receptor α chain gene play no role in the development of atopic eczema in patients who have normal IgE productivity. [ABSTRACT FROM AUTHOR]

Background: Magnesium (Mg2+) has relaxant effects on histamine-induced bronchoconstriction. In addition, Mg2+ has been reported to reduce vascular smooth muscle tone and be clinically useful for treatment of persistent pulmonary hypertension of the newborn. In this study, we evaluated the relaxant effect of Mg2+ on serotonin (5HT)-induced bronchoconstriction and pulmonary hypertension. Methods: Seven mongrel dogs were anesthetized with pentobarbital (30 mg · kg-1+2 mg · kg-1 · h-1) and paralyzed by pancuronium (0.2 mg · kg-1 · h-1). Bronchoconstriction and pulmonary hypertension were elicited with 5HT (10 μg · kg-1+1 mg · kg-1 · h-1). Airway caliber was evaluated by changes in bronchial cross-sectional area (BCA) of the 3rd bronchial bifurcation measured by a fiberoptic bronchoscope method as previously reported. Pulmonary hypertension was assessed by changes in pulmonary vascular resistance (PVR). The BCA and PVR were expressed as per cent of the basal level. Thirty minutes after start of 5HT infusion, magnesium sulfate (MgSO4): 0 (saline), 1, 10, 100 and 1000 μmol · kg-1 was given iv. Arterial blood was also collected to measure plasma level of Mg2+ and catecholamines. Results: 5HT increased %PVR to 163±25% and decreased % BCA by 39.2±4.5%. Plasma level of Mg2+ following MgSO4 1000 μmol · kg-1 iv exceeded its toxic level. The ED50s of MgSO4 (dose producing 50% relaxation of maximal constriction) was 47.8 μmol · kg-1 and 1.09 mmol · kg-1 for pulmonary hypertension and bronchoconstriction, respectively. The ratio of %PVR to %SVR was about 1.0 after MgSO4 0–100 μmol · kg-1 iv, although the ratio significantly increased after 1000 μmol · kg-1 iv. Conclusion: In dogs, 5HT-induced pulmonary hypertension but not bronchoconstriction was significantly reduced by an iv bolus of MgSO4, resulting in a plasma concentration within the assumed therapeutic level. [ABSTRACT FROM AUTHOR]

Two women with multiple xanthomas, intermittent arthritis and thrombocytopenia were diagnosed as phytosterolaemia, an autosomal-recessive lipid storage disease, based on their increased serum concentrations of β-sitosterol, campesterol and sitostanol. The gene responsible for this disease is located within a distance of 18 cM between microsatellite markers of D2S1788 and D2S1352 at chromosome 2p21. We genotyped the patients and their family members with 16 microsatellite markers around this locus. The results from the homozygosity mapping of one family suggested that the gene was located within the distance of 12.6 cM between D2S2328 and D2S1352. We have shortened the genetic distance by 5.4 cM. [ABSTRACT FROM AUTHOR]

Map to microscopic-scale structural analysis of the Hanazono Assemblage of the Shimanto Belt in SW Japan, an excellent example of a deeply buried accretionary complex, indicates a detailed process from underthrusting to underplating. The earliest underthursting process is recorded in fabric of melange, which has deformed by shear along the decollement, characterized by thinning strain due to extensional breakage of blocks of sandstone and exotic materials, such as basalt and pelagic sediments of oceanic affinities. The deformation mechanism for melange formation for domain I is plastic flow, concordant with metamorphic grade, which is higher than that of domain II. The deformation mechanism for domain II is predominantly pressure solution partly with grain-scale brittle breakage for the less metamorphosed part of the Hanazono Assemblage. The posterior underplating process recorded is contraction and thickening due to thrust stacking and folding. Locations of the folds developed beneath thrusts are emphasized because they are a line of evidence of thickening. The main deformation mechanism of the second stage is plastic flow for domain I and cataclasis for domain II. The cataclasis in domain II may be a result of change in strain rate and seems to be related to seismicity at the time of underplating. Kinematics deduced from fabric analysis of the earliest deformed melange indicates a good consistency with a relative plate motion between the Eurasian and oceanic plates that is estimated from a hot spot reference plate circuit model by Engebretson et al. [1985], while that of the subsequent thrusting is not. This fact suggests that strain partitioning in association with oblique subduction of oceanic plate was minimum during subduction. Another possibility for strain partitioning is the requirement of coupling between plates that are recorded by the deformation mechanisms. [ABSTRACT FROM AUTHOR]

Provides information on a study regarding the origin of melange and its role in accretion during underplating. Accretionary complexes at Shimanto Belt in Kii Peninsula in Japan; Duplex structure; Occurrence of melange and melange fabric.

ABSTRACTThis work was undertaken to determine the growth parameters of Lockhart’s equation for finding which component was predominantly contributing to the cell expansion rates of plants subjected to environmental stresses under tissue-culture conditions. Embryos isolated from soybean (Glycine max [L.] Merr.) and kidney bean (Phaseolus vulgaris L.) seeds were grown under tissue-culture conditions. The water potential of culture media ranged from - 0·02 to - 0·94 MPa so that nutrient deficiency and salt stress conditions could be applied. Additionally, the temperature of culture conditions was set from 10 to 40 °C to apply low-temperature and high-temperature stresses on plants grown at the optimum concentration of culture medium. Cell expansion could be inhibited completely by adding 2,4-dichlorophenoxyacetic acid and benzylaminopurine to culture media to form callus tissue. The sizes of the water potential gradient between the water source and elongating cells correlated with the speed of growth rates under nutrient deficiency, salt stress, growth retardation induced by plant hormones, low-temperature and high-temperature conditions in the present study, indicating that cell expansion rates were mainly associated with how much water could be absorbed by elongating cells regardless of the kinds of environmental stress conditions applied. [ABSTRACT FROM AUTHOR]

Mixed culture of nylon non-adherent (T-enriched) spleen cells or lymph node cells of ACI/N or F344 rats with mitomycin C-treated autologous spleen cells resulted in the increased DNA synthesis of the responder T cells when they were cultured in medium containing foetal calf serum (FCS) or bovine Serum albumin. This autologous mixed lymphocyte reaction (AMLR), however, proceeds little when the cells were cultured in medium containing autologous or allogeneic rat serum, irrespective of the responder:stimulator cell ratio and to the culture period. Furthermore, the AMLR response in FCS was greatly reduced if a relatively large number of macrophages were present in the responder cell population. These results suggest that the AMLR response is unlikely to occur in a physiological condition or in [ABSTRACT FROM AUTHOR]

Studies the role of lectin histochemistry as special markers for rodlet cells in carp, Cyprinus carpio L. Lectin-binding patterns for rodlet cells, granulocytes, macrophages and goblet cells; Intracellular granules of rodlet cells; Similarity of the periportal distribution of rodlet cells to those of lymphoid cells and macrophages in the carp head kidney.

Examines macrophages in the chicken oviduct. Influence of sex hormones on presence of macrophages; Localization of the macrophages; Variation of the frequency of the occurrence with oviductal segments.

The rate of chain elongation of palmityl-CoA to stearyl-CoA in rat liver microsomes was studied in connection with the nutritional status of the rats. The microsomal chain elongation activity, which had been decreased by starvation for 48 hr, was rapidly increased to a high level on refeeding. The apparent Km value for malonyl-CoA in both normal and refed rats was the same, 1.2×10 M. Both cycloheximide and actinomycin D prevented the induction of microsomal chain elongation activity which was associated with refeeding. In addition, the activity of acyl-CoA hydrolase and the rates of esterification of acyl-CoA into phospholipids and neutral lipids in microsomes were not changed by the dietary alteration. These results support the conclusion that changes of the activity of microsomal chain elongation of palmityl-CoA in various nutritional status result from a rapid synthesis of new enzyme(s). [ABSTRACT FROM AUTHOR]

The pre-T-cell receptor (TCR) complex, which consists of a heterodimer of the TCRβ-chain and the pre-TCRα-chain, is known to regulate early thymocyte development. The pre-TCR complex contains CD3 subunits as a signal-transducing molecule, but the exact subunit composition of the fully assembled pre-TCR complex remains to be elucidated. In particular, the association of the CD3ζ-chain with the pre-TCR is controversial. In the present study, we have generated a monoclonal antibody against the cytoplasmic portion of the pre-TCRα-chain, and analysed a subunit composition of the pre-TCR complex. We demonstrated that the CD3ζ-chain is physically associated with the pre-TCR in immature T cells. Thus, the result strongly supports the previous findings that CD3ζ contributes to signalling mediated through the pre-TCR complex. [ABSTRACT FROM AUTHOR]

Autologous mixed lymphocyte cultures were set up from nylon non-adherent T-enriched lymphocytes and mitomycin C-treated spleen cells of individual ACI/N rats and the effect on the reaction (AMLR) of sera in the culture medium was studied with regard to the xenogeneic nature of the sera. Not only foetal calf serum, but also sera of adult human, horse and swine stimulated the AMLR response, but autologous or rat serum did not. Albumin fractions of these sera were also effective in inducing the AMLR response. Furthermore, the presence of xenogeneic serum in the culture medium was also required for the blastogenic response of AMLR-primed lymphocytes against the secondary stimulation with syngeneic spleen cells. Both autologous and xenogeneic sera, however, supported the Con-A response of the same responder cell population as used in the AMLR. These results substantiated our previous finding (Endho & Hashimoto, 1981) and suggest that two signals, one from autologous non-T cells and another from the xenogeneic factor in culture medium, are required to cause AMLR, at least in the rat system. [ABSTRACT FROM AUTHOR]

Investigates the locational characteristics of the epithelioid cells in the chicken aorta. Use of an electron microscopic approach; Exposure of the epithelioid cells to the aortic lumen; Aggregation of five or more cells in the intermediate region of the tunica media.