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To monitor the volcanoes at a high spatiotemporal resolution, we introduce the singular value decomposition‐based Wiener filter and the three‐component waveforms in ambient noise velocity monitoring. The continuous ambient noise data from 63 stations around Mt. Fuji and Mt. Hakone, Japan, during the January‐September 2011 were analyzed to estimate the seismic velocity variations at a 1‐day temporal resolution, allowing us to distinguish the velocity drops caused by the 2011 Mw 9.0 Tohoku‐oki and the Mw 6.0 East Shizuoka earthquake. The velocity drop during the Tohoku‐oki earthquake was large in volcanic areas and was larger around Mt. Hakone than Mt. Fuji. This difference is possibly due to the existence of fluid‐ and gas‐rich zones at shallower depths and a higher crack density around Mt. Hakone. In addition, the velocity drop at Mt. Fuji during the Tohoku‐oki and the East Shizuoka earthquake was the same level, despite larger static stress changes beneath Mt. Fuji during the East Shizuoka earthquake. We interpret this inconsistency between the velocity drops and static stress changes to arise from incomplete recovery of the generated cracks during the Tohoku‐oki earthquake when the East Shizuoka earthquake occurred. This study also investigates the spatial variations in recovery speed and recovery amount, finding slow recovery speeds in the volcanic areas and fault areas, possibly due to larger crack densities in the crust. Furthermore, we observe the lowest velocity recovery amount in the volcanic areas, which is likely attributed to the maintained increase in pore pressure due to the volcanic gas bubbles. Plain Language Summary: Ambient noise monitoring is a useful tool to estimate the dynamic behaviors of subsurface conditions, such as crustal stress and pore pressure. In recent years, this monitoring technique has been applied to volcanic eruption prediction, however, the temporal resolution is about 5 or 10 days, which is still insufficient for volcanic eruption prediction. Therefore, we introduce denoising techniques with combination of singular value decomposition and Wiener filter to stably estimate the velocity change in high temporal resolution. As a result, we are able to estimate velocity changes with 1‐day temporal resolution and distinguish the velocity changes caused by the 2011 Mw 9.0 Tohoku earthquake and the Mw 6.0 East Shizuoka earthquake that occurred 4 days after the Tohoku earthquake. The high temporal resolution of this monitoring approach could contribute to volcano monitoring systems, particularly through providing additional information on the state of the volcanic system. Moreover, we model the velocity changes and estimate the spatial variation of recovery speed and recovery amount, which is important to predict the postseimic recovery of velocity changes. We found slow recovery speed in volcanic areas and fault areas, and small recovery amount in volcanic areas. Key Points: Ambient noise monitoring with high temporal resolution (1 day) was applied to volcanic areas (Mt. Fuji and Hakone area)Slow velocity recovery speeds in the volcanic areas and fault areas, possibly due to larger crack densities in the crustThe lowest velocity recovery amount in the volcanic areas could attribute to the maintained high pore pressure due to the volcanic gas [ABSTRACT FROM AUTHOR]

The United Arab Emirates (UAE), located in an arid climate zone with low rainfall, relies on shallow aquifers for freshwater. Understanding the depth and extent of such aquifers is crucial for meeting water supply needs. The UAE's hydrogeology is influenced by neighboring mountains in Oman. The Al‐Jaww Plain in southeast of Al‐Ain city is an essential groundwater source, characterized by a large, flat area of gravel and sand deposits from the Oman Mountains. This study aims to map groundwater aquifers in the Al‐Jaww Plain by integrating the audio‐magnetotelluric (AMT) method, seismic reflection profiling, and borehole data. AMT data were collected along an 11‐km ENE–WSW profile and a 2D resistivity model was generated. The resulting model delineates three distinct geo‐electrical zones from the surface to a depth of 5 km. First, a shallow layer with low resistivity (0–15 Ωm) represents the Quaternary and Pliocene aquifers, in addition to the Upper Cretaceous Simsima and Tertiary groundwater aquifer zone, extending to a depth of 1.5 km. Second, a moderately resistive layer (15–250 Ωm) is recorded beneath the first layer, corresponding to the Upper Cretaceous Aruma foreland basin sequence. Finally, a high‐resistivity region (>250 Ωm) at depths exceeding 3 km is attributed to the allochthonous Hawasina thrust sheet, which is associated with Late Cretaceous obduction of the Semail ophiolite. These findings have practical implications for managing groundwater resources in Al‐Ain. Plain Language Summary: The United Arab Emirates (UAE) has a limited freshwater supply due to its arid climate and low rainfall. Understanding the location and depth of groundwater aquifers is crucial for meeting the country's water needs. This study focuses on mapping the aquifers in the Al‐Jaww Plain, an important potential groundwater source in the Al‐Ain region of the UAE. The researchers used a combination of audio‐magnetotelluric surveys, seismic reflection profiling, and borehole data to create a hydrogeological model of the subsurface. The model revealed three distinct layers at different depths. The shallow layer, with low resistivity, represents the Quaternary, Pliocene, and Upper Cretaceous groundwater aquifers. Below that, a moderately resistive layer corresponds to the Upper Cretaceous Aruma foreland basin sequence. Finally, a high‐resistivity region at greater depths is associated with the allochthonous Hawasina thrust sheet, formed during the Late Cretaceous obduction of the Semail ophiolite. This information is valuable for managing groundwater resources, selecting drilling sites, and estimating groundwater reserves in the Al‐Ain region. Key Points: Groundwater resources investigated using audio‐magnetotelluric (AMT) measurements in Al‐Jaww Plain, United Arab EmiratesIntegration of AMT, seismic, and borehole data revealed hydrogeological insightsQuaternary and Pliocene aquifers identified with resistivity values 0–15 Ωm, extending 1.5 km deep [ABSTRACT FROM AUTHOR]

The fluid‐flow properties of fractures have received increasing attention regarding the role of geofluids in the genesis of slow and fast earthquakes and recent advances in geoengineering developments. Geophysical observations are promising tools to remotely estimate crustal permeability changes; however, quantitative interpretations are limited by the rock‐physical models' paucity for fractures. This study investigated changes in permeability, resistivity, and their respective relationships at elevated stress by performing numerical simulations of different fracture models with varying fracture size, roughness, and shear displacement. Numerical results and microscopic flow analysis demonstrate that permeability–resistivity relationships are controlled by percolation and are less dependent on fracture geometric characteristics. Our finding suggests that the permeability evolution of fractures can be formulated with resistivity changes independent of both fracture size and microstructure, the trends of which can be predicted using Archie's exponent. The extension to the electro‐mechanical relationship further derives the potential applications of estimating stress changes. Plain Language Summary: Monitoring the flow of fluids through underground fractures is important for developing earth resources and understanding the generation of both slow and fast earthquakes. This can be realized by observing physical properties underground such as electrical resistivity; however, the relationships between electrical and hydraulic properties are poorly understood because we have limited data on rock fractures. Thus, in this study, we explored changes in the hydraulic and electrical properties of synthetic rock fractures by subjecting them to increasing normal stress and shear displacement while varying the properties of the fracture surface topographies and length scales referring to natural data. We formulated the relationship between electrical resistivity and permeability invariant of fracture size, roughness, shear displacement, and normal stress based on both the theoretical model and empirical Archie's equation. We found that the rigorous relationship is controlled by the local connection of the fluid‐flow paths based on the microscopic flow analysis. The proposed formula can estimate the permeability evolution of fractures using resistivity data and is a better approach compared to porosity estimation because resistivity–porosity relationship can change depending on the tortuosity or connectivity. The extension to the electro‐mechanical relationship also derives the potential applications of estimating changes in pore pressure. Key Points: Numerical results clarify the dependencies of fracture size, roughness, shear displacement, and stress on permeability and resistivityFlow path percolation can be correlated with tortuosity, which controls the rigorous resistivity–porosity and –permeability relationshipsArchie's exponent is constant for a percolated single fracture and can be used for monitoring permeability and pore pressure change [ABSTRACT FROM AUTHOR]

The causes for forearc basin and megathrust rupture zone segmentation are controversial. The Nankai forearc, Japan, is separated into five domains based on topography: Enshu, Kumano, Muroto, Tosa, and Hyuga. The boundaries of these domains correspond to the rupture limits of large earthquakes. We examined the geologic structure of the boundary region between the Kumano and Muroto domains off the Kii Peninsula using multichannel seismic reflection data to evaluate the role of upper plate composition in controlling segmentation. The results suggest that thick cover sediments and underlying accretionary prism are obliquely thrust landward over the igneous basement complex rock in the region of offshore of Cape Shionomisaki and separate the forearc basin. The igneous basement complex rocks directly overlying the plate interface in the hypocentral regions of 1944 Tonankai and 1946 Nankai earthquakes. The 1944 earthquake originated at the base of the complex, and the rupture extent slipped past its basement boundary, whereas the 1946 event nucleated at the updip boundary of the basement complex. The dense igneous rocks might have worked as a heavily loaded barrier on the seismogenic megathrust and separated the rupture area of both the earthquakes. Upper plate geology may be an important factor in controlling seismogenesis in the Nankai Trough and may serve as an example for understanding the controls on megathrust slip in other subduction zones. Plain Language Summary: The Nankai Trough, Japan is the place where quakes nucleate in the margin and tsunamis repeatedly devastated circum‐Pacific societies. When, where, why, and how the quakes were started in the trench is a central scientific question but unsolved. The historical records of earthquakes suggest that the rupture started around Cape Shionomisaki of the Kii Peninsula, where there is also a topographic segment boundary of the ∼2,000 m deep basin in the middle continental slope. Our research of the geologic structure beneath the earthquake epicenters indicates a dense and hard rock mass situated upon the hypocenters of 1944, and 1946 megaquakes off Cape Shionomisaki. The rock mass might have worked as a heavy load and barrier on the low angle dipping plate boundary fault when the fault slipped the large rupture was propagated in the Nankai Trough. Key Points: The Nankai forearc basin is separated off the Kii Peninsula owing to the existence of middle Miocene igneous basement in the upper plateThe rupture areas of the 1944 Tonankai, 1946 Nankai, and 2016 off‐Mie earthquakes appear to be controlled by the igneous basementThe shallow distribution of very low‐frequency earthquakes and tremors are related to the geological heterogeneity of the upper plate [ABSTRACT FROM AUTHOR]

In an effort to reveal the subsurface hydraulic changes in fractures by seismic monitoring, aperture‐related velocity changes need to be investigated. We developed a numerical approach for calculating changes in elastic wave velocity with fracture aperture opening by determining the internal energy of a digitized fracture model based on natural rough surfaces. The simulated local elastic energy revealed that the interaction energy converged within 1.5 mm of the mean fracture position, and was insignificant unless the fractures intersected. This energetic approach clarified the aperture‐velocity relationship and reproduced the experimental results. Further calculations using digital fractures with various sizes and densities demonstrated that the velocity can be accounted for by the superposition of a linear function of fracture density and quadratic function of aperture, and is insensitive to the fracture size. Although the relationship between fracture permeability and elastic wave velocity (i.e., the k‐V relationship) depends on the fracture density, the offset‐normalized k‐V relationship shows clear linearity with the fracture density. The proposed k‐V relationship as a function of the aperture and fracture density indicates that laboratory‐scale fracture properties of a single fracture can be applied to multiple fractures on a larger scale. Our findings can be used to interpret temporal changes in seismic observations and to monitor fluid flow in fractures. Plain Language Summary: A monitoring of seismic velocity will be useful to find changes in the permeability of fractures, if the relationship between elastic wave velocity and fracture aperture is known. This study presents a numerical approach to calculating changes in elastic wave velocity, based on the elastic energy calculated using a digital rock model having simulated natural fractures. The proposed approach revealed the relationship between fracture aperture and elastic wave velocities propagating through the fracture. Further calculations showed linear decreases of wave velocities with the number of fractured layers per unit thickness (i.e., the fracture density), whereas the velocities do not significantly change with fracture size. Our results will allow us to formulate the relationship between fracture permeability and elastic wave velocity as a function of fracture density. The proposed equation suggests that the properties of a single fracture on the laboratory scale can be used for a large‐scale multiple fracture system. The results will provide a prospective application of seismic data to be used in the sustainable development of fractured reservoirs such as geothermal resources. Key Points: A numerical approach based on internal energy calculations was developed to calculate precise velocity changes with fracture openingVelocity can be accounted for by superposition of a linear function of the fracture density and quadratic function of the aperture sizeNormalized velocity has a linear relationship with normalized permeability, and the trend depends on fracture density [ABSTRACT FROM AUTHOR]

Pore pressure plays a key role in the generation of earthquakes in subduction zones. However, quantitative constraints for its determination are quite limited. Here, we estimate the subsurface pore pressure by analyzing the transient upwelling flow of drilling mud from borehole C0023A of the International Ocean Discovery Program (IODP) Expedition 370, in the Nankai Trough off Cape Muroto. This upward flow provided the first direct evidence of an overpressured aquifer in the underthrust sediments off Cape Muroto. To estimate the pre‐drilling pore pressure in the overpressured aquifer around a depth of 950–1,050 m below sea floor, we examined the measured porosities of core samples retrieved from nearby IODP wells; we then proceeded to explain the observed time evolution of the flow rate of the upwelling flow by modeling various sized aquifers through solving a radial diffusion equation. It was observed that for a permeability of 10−13 m2, the aquifer possessed an initial excess pore pressure of ∼5–10 MPa above the hydrostatic pressure, with a lateral dimension of several hundred meters and thickness of several tens of meters. The overpressure estimates from the porosity‐depth profile at Site C0023 differ from those at other drill sites in the region, suggesting the possible existence of multiple overpressured aquifers with a patchy distribution in the underthrust sediments of the Nankai Trough. As pore pressure is relevant in maintaining fault stability, the overpressured aquifers may be the source of slow earthquakes that have been observed around the drilling site. Plain Language Summary: Fault zones often act as barriers to fluid flow, which can lead to the formation of aquifers of pressurized fluid in the vicinity of the fault. It is well known that pore fluid pressure plays a key role in the generation of subduction zone earthquakes, however quantification of pore fluid pressures around subduction zone faults has, up to now, been limited. The International Ocean Discovery Program (IODP) Expedition 370 drilled the Nankai Trough subduction zone off Cape Muroto (Japan), where slow earthquakes have been observed. While drilling, we observed a transient upwelling flow of drilling mud from the borehole. This flow provided the first direct evidence of an overpressured aquifer around the plate boundary fault. To constrain the properties of the aquifer we modeled aquifers with varying properties, and found that the upwelling mud at the drill‐site was likely generated by an aquifer with a lateral extent of hundreds of meters and with pore pressures considerably higher than the typical (hydrostatic) pore fluid pressure expected at this depth. Our results suggest that slow earthquakes that occur near Cape Muroto may be caused by relatively small, scattered, highly‐pressurized subsurface aquifers like the one we intersected during Expedition 370. Key Points: A transient borehole mud flow confirmed the existence of an overpressured aquifer beneath the Nankai Trough décollement off Cape MurotoThe aquifer of ∼5–10 MPa excess pore pressure was distributed over a lateral extent of hundreds of metersThe overpressured aquifer may have been the cause of slow earthquakes observed near the drilling site [ABSTRACT FROM AUTHOR]

Many significant geological features in central Japan reflect the history of tectonic events such as volcanic eruptions, fault ruptures, and the collision of the Izu‐Bonin arc. Because most previous studies focused on deep, large‐scale structures at relatively low resolution or on local structures using high‐resolution data (e.g., active source seismic data), tectonic structures over a wide area throughout central Japan have not been characterized in detail. In this study, we estimated 3D S wave velocity structures with high spatial resolution by extracting surface waves from 1‐year‐long ambient seismic data recorded by the Hi‐net high‐sensitivity seismograph network. We computed cross spectra of ambient noise data between station pairs and then extracted phase velocity dispersion curves using a frequency domain method. We developed an algorithm to calculate phase velocity and obtained numerous dispersion data. We then estimated the 3D S wave velocity structure by applying a direct surface‐wave inversion method. Our results clearly mapped heterogeneous features such as tectonic lines, sedimentary plains, and volcanic systems. We observed some low‐velocity anomalies below volcanoes. Active fault zones identified as low‐velocity zones were consistent with features on seismic reflection profiles. Several geological blocks that are related to the Izu collision were observed around the Izu Peninsula. We observed previously unreported geological features of the island of Honshu. Our high‐resolution S wave velocity model can be used for not only interpretation of geological structures but also hazard assessment of earthquake. Plain Language Summary: Techniques based on the speed of seismic waves are used to observe features of the Earth's interior in Japan, but most studies using them have focused on deep structures (tens or hundreds of kilometers deep) over a wide area or on local structures with high‐resolution data. The tectonic structures over a wide area throughout central Japan have therefore not been well characterized. Studies of detailed, shallow structures typically use artificial seismic waves; however, these are difficult to do over wide areas due to the cost, safety considerations. In this study, we used only passive sources, generated by ambient (background) vibrations of the Earth, to extract details of the shallow crust and construct a three‐dimensional geologic model based on seismic wave speeds in central Japan. Our results clearly mapped geological features such as tectonic lines, sedimentary plains, and volcanoes. An active fault zone was identified as a low‐speed zone that agreed with features identified in previous studies using active sources. Several geological blocks were identified around the Izu Peninsula, and the features observed on our results reflected processes of the tectonic evolution. Our results can also be used to predict how earthquake waves propagate and thereby contribute to disaster evaluation. Key Points: We estimated a 3D S wave velocity structure for central Japan using surface waves extracted from ambient noiseOur velocity model reflects small‐scale geological features and deformation over a wide areaLow‐velocity anomalies were observed that continue down the dip direction of active reverse faults [ABSTRACT FROM AUTHOR]

Although seafloor massive sulfide (SMS) deposits are crucially important metal resources that contain high‐grade metals such as copper, lead, and zinc, their internal structures and generation mechanisms remain unclear. This study obtained detailed near‐seafloor images of electrical resistivity in a hydrothermal field off Okinawa, southwestern Japan, using deep‐towed marine electrical resistivity tomography. The image clarified a semi‐layered resistivity structure, interpreted as SMS deposits exposed on the seafloor, and another deep‐seated SMS layer at about 40‐m depth below the seafloor. The images reinforce our inference of a new mechanism of SMS evolution: Upwelling hydrothermal fluid is trapped under less‐permeable cap rock. The deeper embedded SMS accumulates there. Then hydrothermal fluids expelled on the seafloor form exposed SMS deposits. Plain Language Summary: Hydrothermal circulation of seawater through the permeable ocean crust engenders formation of seafloor massive sulfide (SMS) deposits, which present high potential for metal mining. Geophysical surveys using modes such as electrical and electromagnetic methods have revealed that SMS deposits exhibit lower resistivity than the surrounding host rock. However, because detailed geophysical images of internal structures of SMS deposits are lacking, the spatial distribution of SMS deposits and the evolutionary processes of SMS deposits remain unclear. For this study, we applied a deep‐towed marine electrical resistivity tomography (ERT) system to capture detailed images of electrical resistivity structures of SMS deposits in the Iheya North hydrothermal field, Okinawa Trough, southwestern Japan. An optimal sub‐seafloor resistivity section reveals a semi‐layered structure consisting of double low‐resistivity SMS layers: exposed and deep‐seated ones. Between the SMS layers, a cap rock layer is recognized as a moderately resistive zone. This detailed structure offers an explanation of how the SMS deposits accumulate: Hydrothermal fluids upwelling from the deep crust are trapped by less‐permeable cap rock, which results in the precipitation and accumulation of SMS deposits below the cap rock. Then fluids passing through the cap rock to the seafloor produce SMS deposits on the seafloor. Key Points: Deep‐towed marine electrical resistivity tomography revealed massive sulfide deposits on the seafloor as low‐resistivity zonesLow‐resistivity zones are semi‐layered with deposits exposed on the seafloor and other deposits at 40‐m depth below the seafloorDetailed near‐seafloor images of electrical resistivity offer an explanation of how the SMS deposits accumulate [ABSTRACT FROM AUTHOR]

Mud volcanoes are among the largest geological sources releasing methane gas. Numerous studies have revealed their origins and compositions released from submarine mud volcanoes. However, quantification of the amount of gas inside submarine mud volcanoes has been challenging due to the difficulty of in situ measurements, which has hampered better evaluation for their contribution to the global methane budget. Here we provide a coupled geochemical and geophysical model that bridges bulk methane concentrations and seismic wave velocities in the mud conduit of submarine mud volcano. This model is applicable to most submarine mud volcanoes and is able to estimate methane concentration at the upper several hundreds of meters in the mud conduits using downhole logging data or seismic data. Our calculation for submarine mud volcanoes in the Eastern Mediterranean and the Nankai plate subduction zones shows that the weight fractions of gaseous and dissolved methane in total weight of sediment are 1,000–3,500 ppm within their mud conduits, which are much higher than previously expected from pore‐water evidence from conventional shallow subsurface sampling. Although more definitive calculations cannot be made until the model parameters are better constrained, our approach provides an opportunity for re‐estimating the global methane budget in submarine mud volcanoes, shedding new light upon the impact of submarine mud volcanism on carbon cycle. Key Points: Gaseous and dissolved methane in the conduits of submarine mud volcanoes is studied by a new coupled geochemical and geophysical approachStudied submarine mud volcanoes showed higher methane concentrations than expected from conventional measurements of sediment coresOur new approach helps reassess a global methane budget in offshore mud volcanoes and their role on global carbon cycle [ABSTRACT FROM AUTHOR]

In the main olfactory system, odours are registered at the main olfactory epithelium and are then processed at the main olfactory bulb (MOB) and, subsequently, by the anterior olfactory nucleus (AON), the piriform cortex (PC) and the cortical amygdala. Previously, we reported populations of vasopressin neurones in different areas of the rat olfactory system, including the MOB, accessory olfactory bulb (AOB) and the AON and showed that these are involved in the coding of social odour information. Utilising immunohistochemistry and a transgenic rat in which an enhanced green fluorescent protein reporter gene is expressed in vasopressin neurones (eGFP-vasopressin), we now show a population of vasopressin neurones in the PC. The vasopressin neurones are predominantly located in the layer II of the PC and the majority co-express the excitatory transmitter glutamate. Furthermore, there is no sex difference in the number of neurones expressing vasopressin. Electrical stimulation of the lateral olfactory tract leads to a significant increase in the number of Fos-positive nuclei in the PC, MOB, AOB, dorsal AON and supraoptic nucleus (SON). However, there was only a significant increase in Fos expression in vasopressin cells of the PC and SON. Thus, functionally distinct populations of vasopressin cells are implicated in olfactory processing at multiple stages of the olfactory pathway. [ABSTRACT FROM AUTHOR]

Given the world's growing demand for energy, a combination of geological CO2 sequestration and enhanced oil recovery (EOR) technologies is currently regarded as a promising solution, as it would provide a means of reducing carbon emissions into the atmosphere while also leading to the economic benefit of simultaneously recovering oil. The optimization of injection strategies to maximize CO2 storage and increase the oil recovery factors requires complicated pore-scale flow information within a reservoir system consisting of coexisting oil, water, and CO2 phases. In this study, an immiscible three-phase lattice-Boltzmann (LB) model was developed to investigate the complicated flow state with interaction between water, oil, and CO2 systems in porous media. The two main mechanisms of oil remobilization, namely, double-drainage and film flow, can be captured by our model. The estimation of three-phase relative permeability is proposed using the digital rock physics (DRP) simulations. The results indicate that the relative permeability of CO2 as calculated using our steady state method is not sensitive to the initial oil fraction if the oil distribution is originally uniform. Baker's (1988) empirical model was tested and found to be able to provide a good prediction of the three-phase relative permeability data. Our numerical method provides a new tool for accurately predicting three-phase relative permeability data directly based on micro-CT rock images. [ABSTRACT FROM AUTHOR]

Synopsis Moisturizers have beneficial effects in treating dry skin. The objective of this study was to evaluate the effect of orange roughy ( Hoplostethus atlanticus) oil, a marine-derived wax ester, on skin dryness in comparison with a reference commercially available petrolatum-based moisturizer (Vaseline) and untreated control. Subjects ( n = 24) with moderate to severe skin dryness at the lower limb of legs (Study 1) and with certain degree of skin dryness on the face and the forearms ( n = 22, Study 2) were treated twice a day for 42 consecutive days with the test products in randomized clinical trials. Transepidermal water loss (TEWL) was measured at the beginning and the end of Study 1, whereas skin hydration was measured at the beginning, after 3 and 6 weeks of the application (the end of the study) in Study 2. Changes in the skin dryness were assessed by a dermatologist using a video microscopy. In Study 1, the dryness score of skin applied with orange roughy oil improved significantly ( P < 0.01) in 6 weeks. The skin looked smooth with no or little dry scaly skin. Orange roughy oil was evaluated with a 60% efficacy in treating skin dryness by the expert, which comparable to that of petrolatum (68%). No significant change in TEWL was found either in orange roughy oil or petrolatum treatment, although the values showed a tendency to improve in both cases. Similarly, the results of the skin capacitance in Study 2 showed a significant improvement of the skin symptoms after 3 and 6 weeks. These results showed that the performance of orange roughy oil in treating skin dryness was comparable to that of petrolatum. [ABSTRACT FROM AUTHOR]

The pituitary gland is a highly mitotically active tissue after birth. Various cell types are known to undergo proliferation in the anterior pituitary. However, little is known about the mechanisms regulating mitotic activity in this tissue. When searching for genes specifically expressed in the pituitary gland among those that we previously screened in Drosophila, we found epithelial cell-transforming gene 2 ( Ect2). Ect2 is a guanine nucleotide exchange factor for Rho GTPases, which is known to play an essential role in cytokinesis. Although there have been many cellular studies regarding the function of Ect2, the temporal and spatial expression patterns of Ect2 in vivo have not been determined. In the present study, we examined the postnatal developmental expression of Ect2 in the mouse pituitary. Enhanced Ect2 expression was detected in the mouse pituitary gland during the first 3 weeks after birth, which coincided well with the period of rapid pituitary expansion associated with increased growth rate. Immunostaining analysis showed that Ect2-expressing cells were distributed in the anterior and intermediate lobes, but not the posterior lobe, of the pituitary. These Ect2-expressing cells frequently incorporated the thymidine analogue, EdU (5-ethynyl-2′-deoxyuridine), indicating that these cells were mitotically active. Taken together, the results demonstrate the functional role of Ect2 in postnatal proliferating cells in the two lobes of the pituitary, thereby suggesting roles in developmental growth of the mammalian pituitary. [ABSTRACT FROM AUTHOR]

Forelimb-girdle muscular anomaly is an autosomal recessive disorder of Japanese black cattle characterized by tremor, astasia and abnormal shape of the shoulders. Pathological examination of affected animals reveals hypoplasia of forelimb-girdle muscles with reduced diameter of muscle fibres. To identify the gene responsible for this disorder, we performed linkage mapping of the disorder locus using an inbred pedigree including a great-grand sire, a grand sire, a sire and 26 affected calves obtained from a herd of Japanese black cattle. Two hundred and fifty-eight microsatellite markers distributed across the genome were genotyped across the pedigree. Four markers on the middle region of bovine chromosome 26 showed significant linkage with the disorder locus. Haplotype analysis using additional markers in this region refined the critical region of the disorder locus to a 3.5-Mb interval on BTA26 between BM4505 and MOK2602. Comparative mapping data revealed several potential candidate genes for the disorder, including NRAP, PDZD8 and HSPA12A, which are associated with muscular function. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Maspin expression is up-regulated during the progression of endometrioid endometrial carcinoma," in previous issue of Histopathology.

The article offers information on the effects of long-term methyl paraben (MP) exposure on skin keratinocytes. Extensive application of dermatological formulations may result in skin allergy and irritation. An analysis was made on the proliferating ability, apoptotic cells, morphological changes, messenger RNA, as well as protein expression of daily application of MP in the stratum corneum (SC) of the human forearm. The results of the study showed that long-term MP exposure resulted in MP persistence and accumulation in the SC. Accumulation of MP in the human skin might influence differentiation of keratinocytes and aging.

The chromosomal location of the resistance gene for green rice leafhopper (GRLH), an injurious insect for rice, has been determined and RFLP markers closely linked to this gene have been identified. The susceptible japonica rice variety ‘Nipponbare’ was crossed with a resistant japonica rice line ‘Aichi42’, in which green rice leaf hopper resistance had been introduced from an indica variety ‘Rantaj-emas2’, and the 100 F2 plants obtained were used for linkage analysis. The green rice leafhopper resistance gene, Grh3(t), was mapped between RFLP markers C288B and C133A on chromosome 6 and co-segregated with C81. Of the RFLP markers tightly linked to Grh3(t), C81 was converted to a SCAR marker and C133A to a cleaved amplified polymorphic sequence marker that could distinguish the heterozygous genotype to establish an effective marker-aided selection system for the GRLH resistance gene. [ABSTRACT FROM AUTHOR]

Tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis in many transformed cells, but not in normal cells, and hence TRAIL has recently emerged as a novel anti-cancer agent. Adult T-cell leukaemia lymphoma (ATLL) is a neoplasm of T-lymphocyte origin aetiologically associated with human T-lymphotropic virus type 1 (HTLV-I), and is resistant to standard anti-cancer therapy. We thus characterized the sensitivity of ATLL cells to TRAIL in this study. Although most primary ATLL cells and cell lines expressed TRAIL death receptors on their surface, they showed only restricted sensitivity to TRAIL. Among the 10 ATLL cell lines examined, one was sensitive, but two had insufficient death-receptor expression, two had an unknown resistant mechanism with abrogation of the death signal upstream of caspase-8, and the remaining five showed attenuation of the signal in both extrinsic and intrinsic pathways by X-linked inhibitor of apoptosis and Bcl-2/Bcl-xL respectively. Furthermore, the level of HTLV-I tax expression was significantly correlated to TRAIL resistance. Interestingly, ATLL cells themselves expressed TRAIL on the cell surface. Constitutive production of TRAIL may offer resistance, thus allowing the development of TRAIL-resistant ATLL cells. Consequently, the resistant mechanism in ATLL cells against TRAIL was assigned to multiple factors and was not explained by a definitive single agent. [ABSTRACT FROM AUTHOR]

Enhanced expression of decay-accelerating factor and CD59/homologous restriction factor 20 in intestinal metaplasia, gastric adenomas and intestinal-type gastric carcinomas but not in diffuse-type carcinomas Aims: Variable expression of the complement regulatory proteins, decay-accelerating factor, CD59/homologous restriction factor 20 (HRF20) and membrane cofactor protein has been shown in human gastrointestinal malignancies, but their expression in gastric cancer has not been fully described. Thus, we immunohistochemically defined the distribution of these proteins in human normal gastric mucosa, intestinal metaplasia, adenomas and gastric cancers. Methods and results: Gastric tissues were obtained by endoscopic biopsy or surgical resection and stained with mouse monoclonal antibodies to decay-accelerating factor, CD59/HRF20, and membrane cofactor protein. In the normal gastric mucosa, membrane cofactor protein was diffusely stained on the basolateral surface of epithelial cells, whereas the expression of decay-accelerating factor and CD59/HRF20 was inconspicuous. In intestinal metaplasia, adenoma and intestinal-type gastric carcinoma cells, decay-accelerating factor and HRF20 were intensely stained on the apical surface; membrane cofactor protein retained its location on the basolateral surface. In diffuse-type gastric carcinomas, the expression of decay-accelerating factor, CD59/HRF20 was lost, but membrane cofactor protein was present on the tumour cell surface. Conclusions: These findings suggest that membrane cofactor protein plays a primary role in the regulation of complement activation in normal and neoplastic gastric cells and that the expression pattern of the complement regulatory proteins is closely related to gastric carcinoma development. [ABSTRACT FROM AUTHOR]

cDNA clones corresponding to the swine histocompatibility complex (SLA: swine leucocyte antigen)-DM α chain were isolated using the polymerase chain reaction (PCR) products from the third exon in the human HLA-DMA gene as a probe. Amino acid comparative analysis revealed that these clones were more closely related to the bovine and human DMA genes than to the other swine class II genes α chain genes, DRA, DQA and DOA. These results suggest that the SLA-DMA gene is expressed and may function, like HLA-DM, as an important modulator in class II restricted antigen processing in swine. Furthermore, based on the sequences and PCR–restriction fragment length polymorphism (PCR–RFLP) patterns in the SLA-DMA gene, no allelic variation was recognized in the second exon, but five allelic variations were recognized in the third exon in five different breeds of swine. These DMA alleles were defined by variation at four nucleotide positions. Two of these alleles resulted in an amino acid substitution. These results suggest that SLA-DMA has little polymorphism as observed in HLA-DMA and mouse H2-Ma. [ABSTRACT FROM AUTHOR]

Aims/Background: Extracellular matrix (ECM) may affect the function and phenotype of hepatocytes. Phenotypic changes of hepatocytes in diseased liver were investigated with reference to ECM composition. Methods: Immunohistochemistry was performed on biopsied liver samples from chronic viral hepatitis (CVH), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and normal patients, using monoclonal antibodies for laminin, type IV collagen, cytokeratin 19 (CK19) and epithelial glycoprotein (EGP), a protein homologous to nidogen. Results: In normal controls, both EGP and CK 19 were expressed exclusively on biliary epithelia. Laminin and type IV collagen were expressed around portal bile ducts and blood vessels. Although type IV collagen was expressed in Disse's space, laminin was scarcely expressed. In all pathological livers, both EGP and CK 19 were expressed in proliferated bile ductules. In CVH with piecemeal necrosis, EGP was expressed on periportal hepatocytes, while CK19 expression was limited to a few hepatocytes. Laminin was expressed in Disse's space of periportal sinusoids, where EGP was expressed on hepatocytes. EGP expression on hepatocytes and laminin deposition in Disse's space were rare in PBC and PSC liver. Conclusion: These results suggest that hepatocytes transform into a phenotype similar to biliary epithelia and, laminin deposition in Disse's space (capillarization of sinusoids) may play a role in this phenotypic change. [ABSTRACT FROM AUTHOR]

Aberrations of chromosomes 3 and 17 were studied by FISH using centromere-specific DNA probes in 11 salivary adenoid cystic carcinomas (ACC) and 8 salivary pleomorphic adenomas (PA), with 3 lymph nodes as controls. Two hybridized signals were detected in 92.8 +/- 2.7% of controls, 73.2 +/- 7.0% of PA and 66.8 +/- 7.9% of ACC cells for chromosome 3, and in 90.4 +/- 2.3% of controls, 59.5 +/- 25.0% of PA and 44.8 +/- 20.2% of ACC for chromosome 17. More than 3 hybridized signals, which indicate polysomy, were observed in 3.1% of controls, 15.5% of PA and 22.9% of ACC cells for chromosome 3, and in 1.2% of controls, 10.3% of PA and 23.1% of ACC cells for chromosome 17. A single hybridized signal was much more frequent for chromosome 17 than for chromosome 3. These findings suggest that polysomy of both chromosomes occurs during the development of salivary gland tumors, and its frequency is increased in adenoid cystic carcinoma as compared to pleomorphic adenoma. In addition, monosomy of chromosome 17 could possibly be significant in salivary gland tumors. [ABSTRACT FROM AUTHOR]

An immunohistochemical study of p53 protein was carried out on 45 salivary gland lesions using a monoclonal antibody, Bp53-12, raised to the intracellular domain of the p53 protein. p53 protein expression was found in 34.4% of 32 salivary gland carcinomas. Nuclear p53 expression was detected in tumor cells but not in non-neoplastic cells, except in one salivary duct carcinoma. The perinuclear cytoplasm of luminal duct cells was specifically positive for the antibody used here. Cytoplasmic p53 expression was observed mostly in non-neoplastic cells. There was a tendency for the cytoplasmic staining of p53 protein to be observed in the normal cells adjacent to p53-positive carcinomas, but none of the normal cells were positive in the tissues surrounding p53-negative carcinomas. Cytoplasmic expression of p53 protein in salivary gland tissues seems to be correlated with tumorigenesis. [ABSTRACT FROM AUTHOR]

In the work described here it was determined if and how unnicking in the A subunit of Escherichia coli enterotoxin at Arg192 or nearby residues affected biological activities of the toxin. The mutant toxin was constructed to lack the nick site in the A subunit by deleting the tripeptide Arg192-Thr193-Ile194, which is essential for toxicity. The mutant toxin did not exhibit agmatine ADP-ribosyltransferase activity in the presence or absence of the ADP-ribosylation factor and had less diarrheal activity and lower induction of cyclic AMP than did LT. The mutant toxin exhibited a much stronger adjuvant action on antibody responses to measles virus, keyhole limpt haemocyanin, bovine immunoglobulin and ovalbumin compared with LT. The altered toxicity of the mutant toxin might be closely related to the potent adjuvant action on antibody responses to antigens. The relationship between two activities is discussed. [ABSTRACT FROM AUTHOR]

A 41-year-old woman with localized lipodystrophy histologically showed lymphohistiocytic inflammation within adipose tissue at the periphery and loss of adipose tissue in the center of the lesion. Ultrastructurally, various degrees of lipophagocytosis by macrophages and giant cells were seen, starting with the projection of cytoplasmic processes into the fat droplet and engulfing pieces of the fat droplet which finally were digested. Laboratory investigations revealed a high serum y-globulin level and a positive antinuclear antibody, suggestive of a connective tissue disease or autoimmue disease. [ABSTRACT FROM AUTHOR]

Eight cases with striae distensae associated with obesity or pro-longed corticosteroid intake were examined by light and scanning electron microscopy. Fine elastic fibers predominated in early lesions, while thick elastic fibers predominated in older lesions. In early lesions the periphery showed thick and tortuous elastic fibers, but in older lesions it was of normal appearance. It is suggested the elastic fibers in striae were newly synthesized and gradually increased and thickened with age. [ABSTRACT FROM AUTHOR]

Three patients are reported, each with a reddish macule or plaque (7-10 mm) induced by trauma. The histology of these lesions showed hyperkeratosis, acanthosis and marked dilation of vessels in the papillary to deep dermis. The electron microscopic study revealed a layer of endothelial cells surrounding the dilated vessels, suggestive of telangiectasia. The relationship between this entity and solitary angiokeratoma is discussed. [ABSTRACT FROM AUTHOR]

Deep wrinkles of 6 elderly people were investigated using electron microscopy. There were ultrastructural differences in the elastotic changes between the area of the wrinkle and the surrounding areas. Elastic fibers containing electron-dense inclusions were mostly seen in the upper dermis of the wrinkled area and were considered to be an early event of the elastotic changes. The elastotic changes showing net-like structures were seen in the areas surrounding the wrinkle and were considered to be a more advanced event. Another form of elastotic change was the presence of thickened elastic fibers with many holes containing round bodies, which were scattered in the deep dermis of the wrinkled area, and increased and packed in the middle and deep dermis of the surrounding areas. In one case subepidermal amyloid deposits were seen in the areas surrounding the wrinkle, suggesting a close relationship between amyloid and sun-light exposure. [ABSTRACT FROM AUTHOR]

Cutaneous scar tissue (atrophic and hypertrophic) and normal dermis were examined using scanning (SEM) and transmission electron microscopy (TEM) as well as light microscopy (LM). Although LM revealed only a few Weigert stain-positive elastic fibers in scar tissue, SEM and TEM disclosed the presence of a large number of fine elastic fibers which was not present in normal dermis. Atrophic scar tissue contained more Weigert stainpositive fibers and fewer fine elastic fibers than hypertrophic scar tissue. In addition, findings suggestive of newly synthesized elastic fibers were seen in some hypertrophic scar tissue. These results indicate that there is elastogenesis in scar tissue. [ABSTRACT FROM AUTHOR]

The back skin of a 15-year-old girl with Marfan syndrome has been investigated using scanning (SEM) and transmission (TEM) electron microscopy. The SEM showed that admixed with normal-looking portions, there were abnormal portions of the elastic fibers which were composed of many unusual fine fibers (5-22 nm in diameter), and had a cobweb-like appearance. The TEM showed that these fine fibers were substructures of the amorphous material and were surrounded by microfibrils. It is suggested that the fine fibers could he abnormal elastic fibers resulting from the incomplete fusion of the elastic units. [ABSTRACT FROM AUTHOR]

The surface structure of altered elastic fibers and elastotic material in solar elastosis has been described using a scanning electron microscope. There were 3 different areas in the dermis, depending on the degree of changes in elastic fibers: areas of (1) normal-looking fibers. (2) thick, cylindrical fibers, and (3) a large mass of markedly changed fibers. They were mainly located in the deep, middle, and upper dermis, respectively. The normal-looking fibers were the same as the normal elastic fiber. The thick, cylindrical fibers showed various findings ranging from relatively normal to heavily damaged surface. The large mass was composed of a cord-like element and a fine net-like one. There was a transition between the thick, cylindrical fibers and the large mass. It is suggested that the thick, cylindrical fiber is an early event and the mass is more damaged. as one of the elastotic changes in solar elastosis. It is also suggested that the thick, cylindrical fiber corresponds to the fibrous form and the mass to the amorphous form of the elastotic material. [ABSTRACT FROM AUTHOR]

ACh usually induced biphasic vascular responses, i.e. an initial vasodilation followed by a secondary constriction, in isolated and perfused basilar arteries from the dog., In dog vessels the vasoconstriction induced by ACh was not modified by treatment with phentolamine, at dose levels which suppressed noradrenaline-induced constriction, but was completely blocked by atropine. The dilation to ACh was also blocked by atropine. Physostigmine caused a potentiation of both ACh-induced dilator and constrictor responses., In dogs, ACh-induced constrictor responses were markedly potentiated, and the vasodilatation was slightly but insignificantly enhanced after treatment with intraluminal saponin which removed the endothelia of the arteries., In basilar arteries from monkeys, ACh usually induced a monophasic vasoconstriction in non-treated preparations., In monkey vessels, ACh-induced vasoconstriction was markedly potentiated and frequently vasodilatation appeared after intraluminal saponin treatment., From these results, it is concluded that ACh has primary vasoconstrictor and vasodilator properties in canine and simian cerebral basilar arteries. [ABSTRACT FROM AUTHOR]

An immunohistochemical study of c-erbB-2 oncoprotein expression was carried out on 201 cases of primary salivary gland tumors, using a polyclonal antibody, raised to the intracytoplasmic domain of the c-erbB-2 oncogene product. An intense membrane reactivity was observed in one case of sialocarcinoma transformed from pleomorphic adenoma (n = 8) and one case of mucoepidermoid carcinoma (n = 22). A comparative histopathologic evaluation of c-erbB-2 positive tumors showed marked variation in cell size, nuclear pleomorphism, multinucleation, a high mitotic rate and increased lymphoid cell infiltration and an aggressive clinical course with poor survival. The results indicate that c-erbB-2 oncoprotein is rarely expressed in malignant salivary gland tumors. However, the overexpression appears to have a distinct histopathologic feature, but a larger study incorporating histopathology and clinical data would be necessary to correlate the significance of c-erbB-2 oncogene product in salivary malignant tumors. [ABSTRACT FROM AUTHOR]