Recovery Strategy for Overturned Wheeled Vehicle Using a Mobile Robot and Experimental Validation.

This paper describes mobile robot tactics for recovering a wheeled vehicle that has overturned. If such a vehicle were to tip over backward off its wheels and be unable to recover itself, especially in areas where it is difficult for humans to enter and work, overall work efficiency could decline significantly, not only because the vehicle is not able to perform its job, but because it becomes an obstacle to other work. Herein, the authors propose a robot-based recovery method that can be used to recover such overturned vehicles, and the authors evaluate its effectiveness. The recovery robot, which uses a mounted manipulator and hand to recover the overturned vehicle, is also equipped with a camera and a personal computer (PC). The ARToolKit software package installed on the PC detects AR markers attached to the overturned vehicle and uses the information they provide to orient itself in order to perform recovery operations. A statics analysis indicates the feasibility of the proposed method. To facilitate these operations, it is also necessary to know the distance between the robotic hand and the target position for grasping of vehicle. Therefore, a theoretical analysis is conducted, and a control system based on the results is implemented. The experimental results obtained in this study demonstrate the effectiveness of the proposed system.

Interaction of Gal-7 with HMGCS1 In Vitro May Facilitate Cholesterol Deposition in Cultured Keratinocytes.

Three-hydroxy-3-methylglutaryl coenzyme A synthase (HMGCS) 1 was identified to interact with Gal-7, a pro-apoptotic ß-galactoside‒binding protein, by yeast two-hybrid system. Their interaction was confirmed by in vitro ß-galactosidase, Biacore, and immunoprecipitation assays. A distinct interactive site of HMGCS1 was found to reside at phenylalanine 26. The expression of HMGCS1 in cultured keratinocytes was upregulated by exogenous Gal-7 and downregulated in LGALS7 small interfering RNA‒transfected cells. HMGCS1-overexpressing cells were found to induce Gal-7 expression, which suggests that Gal-7 and HMGCS1 expressions are both stimulated by positive feedback regulation. The amount of cholesterol, a final biosynthetic product of HMGCS1-involved pathway, was increased in Gal-7‒treated cells and was significantly reduced in LGALS7 small interfering RNA‒transfected cells. The increase of cholesterol level in Gal-7‒treated cells was inhibited by wild-type HMGCS1 peptide but not by phenylalanine 26‒mutated peptide, suggesting that the interaction of Gal-7/HMGCS1 is related to cellular cholesterol level. Foam cells in granulomatous tissues of the specimens from normolipidemic cutaneous xanthoma showed positive reactions with the antibodies for Gal-7 and HMGCS1 as well as for lipid markers. These results are likely to indicate that Gal-7 induction in epidermal keratinocytes causes both apoptotic cell death and HMGCS1-mediated cholesterol accumulation, which will be phagocytized by macrophages. This mechanism may explain the pathogenesis of normolipidemic cutaneous xanthoma.

Multilayer graphene shows intrinsic resistance peaks in the carrier density dependence.

Since the advent of graphene, a variety of studies have been performed to elucidate its fundamental physics, or to explore its practical applications. Gate-tunable resistance is one of the most important properties of graphene and has been studied in 1-3 layer graphene in a number of efforts to control the band gap to obtain a large on-off ratio. On the other hand, the transport property of multilayer graphene with more than three layers is less well understood. Here we show a new aspect of multilayer graphene. We found that four-layer graphene shows intrinsic peak structures in the gate voltage dependence of its resistance at zero magnetic field. Measurement of quantum oscillations in magnetic field confirmed that the peaks originate from the specific band structure of graphene and appear at the carrier density for the bottoms of conduction bands and valence bands. The intrinsic peak structures should generally be observed in AB-stacked multilayer graphene. The present results would be significant for understanding the physics of graphene and making graphene FET devices.

Low-energy band structure and even-odd layer number effect in AB-stacked multilayer graphene.

How atoms acquire three-dimensional bulk character is one of the fundamental questions in materials science. Before addressing this question, how atomic layers become a bulk crystal might give a hint to the answer. While atomically thin films have been studied in a limited range of materials, a recent discovery showing how to mechanically exfoliate bulk crystals has opened up the field to study the atomic layers of various materials. Here, we show systematic variation in the band structure of high mobility graphene with one to seven layers by measuring the quantum oscillation of magnetoresistance. The Landau fan diagram showed distinct structures that reflected differences in the band structure, as if they were finger prints of multilayer graphene. In particular, an even-odd layer number effect was clearly observed, with the number of bands increasing by one for every two layers and a Dirac cone observed only for an odd number of layers. The electronic structure is significantly influenced by the potential energy arising from carrier screening associated with a gate electric field.

Accumulation of C-reactive protein in basal keratinocytes of normal skins.

BACKGROUND: C-reactive protein (CRP) is a prototypic acute phase protein which increases dramatically in the blood during the first 48h of tissue inflammation and has been recognized as a risk factor for atherosclerosis. CRP interacts with a variety of proteins. OBJECTIVE: To know the role of accumulated CRP in the skin. METHODS: Interaction of CRP with basal keratinocytes was studied using immunohistochemical method and keratinocyte culture system. RESULTS: We found an immunohistochemical deposition of CRP on the basal keratinocyte membrane in some normal human skins (23 out of 46 skins). When added to cultured keratinocytes, heat-denatured but not native CRP was found to adhere to keratinocyte cell membrane after 1h, then internalized into cytoplasm after 24h. The heat-denatured CRP recognized at least four keratinocyte polypeptides with the molecular weights of 56, 42, 32 and 24kDa. Ligand binding assays suggested that multiple populations of receptor-ligand interactions were involved in the binding between CRP and keratinocyte. Cultured dermal microvascular endothelial cells were found to express CRP of which expression was greatly induced by interleukin-1ß (IL-1ß) treatment, suggesting that the deposited CRP in the basal keratinocytes can be derived from local dermal microvasculatures as well as from systemic circulation (serum). Treatment of cultured keratinocytes with heat-denatured CRP induced interleukin-8 (IL-8) expression, a potent leukocyte chemotactic cytokine. CRP in the medium (liquid phase) and CRP-coated dishes (solid phase) both inhibited the adhesion of keratinocytes in culture. CONCLUSION: Accumulation of CRP may regulate the skin inflammation and keratinocyte proliferation by modulating keratinocyte cytokine expression and adhesion to substrate.

Evaluation of unique elastic aggregates (elastic globes) in normal facial skin by multiphoton laser scanning tomography.

BACKGROUND: There is no reliable marker to estimate the degree of skin aging in vivo. It now has become possible to quantitatively determine the dermal characteristics of the extracellular matrix (ECM) in vivo using multiphoton laser tomography (MLT). METHODS: Fifty-seven healthy Japanese female volunteers, aged from 20 to 60 years old, were examined using multiphoton depth-resolved measurements of autofluorescence (AF) and second harmonic generation (SHG) at three sites on their right cheek. Paraffin-embedded skin specimens obtained from the faces of 12 normal individuals aged 38-68 years old were stained with Elastica van Gieson (EVG). RESULTS: We found unique elastic aggregates at a 20 µm depth from the dermo-epidermal junction (DEJ) in vivo which increased in size with aging of subjects from 20 to 60 years old. SHG fibers seemed to surround those elastic aggregates. Histological examination of specimens from normal individuals stained with EVG confirmed the occurrence of elastic aggregates with varied sizes just beneath the epidermis or hair follicles. CONCLUSIONS: The elastic aggregates are morphologically similar to previously described 'elastic globes' and can serve as a marker of the early stage of photoaging. MLT will contribute to determine age-related dermal changes using a non-invasive technique.

In vitro amyloidogenic peptides of galectin-7: possible mechanism of amyloidogenesis of primary localized cutaneous amyloidosis.

Pathogenesis of primary localized cutaneous amyloidosis (PLCA) is unclear, but pathogenic relationship to keratinocyte apoptosis has been implicated. We have previously identified galectin-7, actin, and cytokeratins as the major constituents of PLCA. Determination of the amyloidogenetic potential of these proteins by thioflavin T (ThT) method demonstrated that galectin-7 molecule incubated at pH 2.0 was capable of binding to the dye, but failed to form amyloid fibrils. When a series of galectin-7 fragments containing ß-strand peptides were prepared to compare their amyloidogenesis, Ser(31)-Gln(67) and Arg(120)-Phe(136) were aggregated to form amyloid fibrils at pH 2.0. The rates of aggregation of Ser(31)-Gln(67) and Arg(120)-Phe(136) were dose-dependent with maximal ThT levels after 3 and 48 h, respectively. Their synthetic analogs, Phe(33)-Lys(65) and Leu(121)-Arg(134), which are both putative tryptic peptides, showed comparable amyloidogenesis. The addition of sonicated fibrous form of Ser(31)-Gln(67) or Phe(33)-Lys(65) to monomeric Ser(31)-Gln(67) or Phe(33)-Lys(65) solution, respectively, resulted in an increased rate of aggregation and extension of amyloid fibrils. Amyloidogenic potentials of Ser(31)-Gln(67) and Phe(33)-Lys(65) were inhibited by actin and cytokeratin fragments, whereas those of Arg(120)-Phe(136) and Leu(121)-Arg(134) were enhanced in the presence of Gly(84)-Arg(113), a putative tryptic peptide of galectin-7. Degraded fragments of the galectin-7 molecule produced by limited trypsin digestion, formed amyloid fibrils after incubation at pH 2.0. These results suggest that the tryptic peptides of galectin-7 released at neutral pH, may lead to amyloid fibril formation of PLCA in the intracellular acidified conditions during keratinocyte apoptosis via regulation by the galectin-7 peptide as well as actin and cytokeratins.

Increase of elastic fibers in lichen sclerosus et atrophicus.

BACKGROUND: Lichen sclerosus et atrophicus (LSA) is histopathologically characterized by upper dermal hyalinization with vacuolar alteration, whereas no particular microscopic change in the mid to lower dermis has been described. The purpose of this study was to investigate any histopathologic changes involving elastic fibers in the mid to lower dermis in patients with LSA. METHODS: We surveyed 22 paraffin-embedded specimens of vulval (18 cases) and extragenital (4 cases) LSA. The sliced skin sections were stained with elastic van Gieson (EVG), and then the degree of elastic fiber change was determined. RESULTS: We found an increase in elastic fibers in the mid to lower dermis in contrast to a decrease or disappearance of elastic fibers in the superficial hyalinized dermis. The level of increase of elastic fibers varies from normal (8/22 cases) to moderate (7/22 cases) to advanced (7/22 cases) levels. CONCLUSIONS: An increase in elastic fibers in the mid to lower dermis may reflect a repairing process in response to the degraded upper dermal elastic fibers, which could be related to the pathogenesis of LSA.

Galectin-7 and actin are components of amyloid deposit of localized cutaneous amyloidosis.

The precursor protein of localized cutaneous amyloidosis (LCA) is believed to be cytokeratins on the basis of previous immunohistochemical studies. To identify the candidate amyloid protein biochemically, amyloid proteins were extracted with distilled water from lesional skin of LCA associated with Bowen's disease. The proteins were resolved on one- or two-dimensional polyacrylamide gel electrophoresis followed by characterization with immunoblot analysis. The proteins with multiple molecular weights of 50-67 kDa and two proteins with 25 and 35 kDa were identified as keratins, serum amyloid P component and apolipoprotein E, respectively. The unknown 14-kDa (pI = 7.0) and 42-kDa (pI = 5.4) proteins reacted with the antibody against galectin-7 and actin, respectively. The protein with the molecular weight of 14 kDa was identified as galectin-7 by MALDI-TOF mass spectrometer. Their electrophoretic mobilities were identical with normal counterparts extracted from cultured normal human keratinocytes. Galectin-7 and actin were detected by immunoblot assay in the water-soluble fractions prepared from the lesional skins of two patients with primary LCA. Immunohistochemical studies of tumor-associated (n = 9) and primary (n = 10) LCA revealed various degrees of positive immunoreactivities with the antibodies for galectin-7 and F-actin. Galectin-7 and actin, which contain considerable amount of ß-sheet structure, may be candidate amyloidogenic proteins of primary and secondary LCA.

UVB irradiation down-regulates type XVI collagen expression in mouse and human skin.

BACKGROUND: Type XVI collagen is a member of the fibril-associated collagens with interrupted triple helices; however, its function or regulation remain unclear. AIMS: This study is to examine the effect of ultraviolet B (UVB) or photoaging on type XVI collagen expression in various cultured cells, mouse, and human skin. METHODS: The level of α1 (XVI) collagen mRNA was determined by quantitative real-time reverse transcriptase-polymerase chain reaction and the localization of type XVI collagen in normal human skins was detected by theα1 (XVI) collagen polypeptide antibody. RESULTS: Exposure of keratinocytes resulted in suppression of mRNA level in a dose- and time-dependent manner and in normal fibroblasts or organotypic cocultures was also inhibited. Expression level in hairless mouse skin was decreased by UVB exposure. Messenger RNA level of human skins in the sun-protected area appeared to be greater than that in the sun-exposed area. Sun-protected and sun-exposed normal skin taken from young subjects showed positive immunoreactivities with the anti-α1 (XVI) collagen antibody in the subepidermal region, whereas sun-exposed skin from elderly subjects exhibited negative immunoreaction. CONCLUSIONS: Reduction of type XVI collagen by UVB irradiation in vitro and in vivo may be related to the alteration of extracellular matrix in the photodamaged skin.

Bullous pyoderma gangrenosum: a case report and review of the published work.

Pyoderma gangrenosum (PG) is an ulcerative skin disorder characterized by neutrophilic infiltrations. PG is generally classified into four types: (i) ulcerative; (ii) pustular; (iii) bullous; and (iv) vegetative. Among them, bullous PG is known as a rare type. Herein, we report a case of bullous PG together with a summary of the 12 PG cases treated in our department over the previous 15 years, and we review 38 well-documented bullous PG cases (65.8% female; aged 18-80 years [mean ± standard deviation, 51.6 ± 16.8]) in the published work, including the present case, from 1972-2011. Although the disease most frequently associated with PG is inflammatory bowel disease, bullous PG is most commonly associated with hematological disorders (25/38, 65.8%), which indicates the characteristic pathophysiology specific to bullous PG.

Two cases of erythema exsudativum multiforme associated with Chlamydia pneumoniae infection.

We report two cases of erythema exsudativum multiforme (EEM) that we concluded were caused by infections with Chlamydia pneumoniae. High titers of IgG antibody for Chlamydia pneumoniae were shown in the sera of both cases. One case showed the classical symptoms of pneumonia together with radiological changes in the chest; the other case did not show these symptoms. To the best of our knowledge, only three cases of erythema multiforme associated with Chlamydia pneumoniae infection have been reported.

N(ɛ)-(carboxymethyl)lysine modification of elastin alters its biological properties: implications for the accumulation of abnormal elastic fibers in actinic elastosis.

Accumulation of degenerated elastic fibers in the sun-exposed skin designated as actinic elastosis is a histological hallmark of photodamaged skin. Previous studies have indicated that the elastic fibers of actinic elastosis interact with lysozyme and are modified by N(ɛ)-(carboxymethyl)lysine (CML), one of the major advanced glycation end products (AGEs). We studied here how CML modification of elastin is involved in the pathogenesis of actinic elastosis. The CML-modified insoluble elastin became resistant to neutrophil elastase digestion, which was reversed by treatment with aminoguanidine, a potent inhibitor of AGE formation. In a temperature-dependent aggregation assay, CML-modified elastin rapidly formed self-aggregates, the size of which was larger than unmodified elastin. The elastic fiber sheets prepared from CML-modified α-elastin showed 3D wider diameter, tortuous appearance, and decreased elasticity on tensile tests. The CML-modified α-elastin, but not unmodified α-elastin, was found to bind to lysozyme in vitro, supporting the immunohistochemical findings that the antibodies for lysozyme and CML reacted simultaneously with the elastic fibers of actinic elastosis and UV-irradiated skin. The glycated elastin is likely to cause the accumulation of abnormally aggregated elastic fibers and unusual interaction with lysozyme in actinic elastosis.

Dermal carbonyl modification is related to the yellowish color change of photo-aged Japanese facial skin.

BACKGROUND: The photo-aged facial skin is characterized by various unique features such as dark spots, wrinkles, and sagging. Elderly people, particularly Asians, tend to show a yellowish skin color change with photo-aging. However, there has been no analytical study conducted on this unique skin color change of the aged facial skin. OBJECTIVE: The purpose of the present study is to examine whether the carbonyl modification in the dermal protein is involved in the yellowish color change that occurs in the photo-aged skin. METHODS: Normal skin samples excised from the face, abdomen and buttock of variously aged Japanese were separated into the epidermal and the dermal portions. These skin samples were histologically examined for carbonyl modification. Moreover, an in vitro constructed dermis model composed of a contracted collagen gel was treated with acrolein or 4-hydroxynonenal. All these samples were also studied colorimetrically. RESULTS: The dermal samples obtained from the photo-aged facial skin exhibited an appearance of yellowish color, whereas neither the facial epidermis nor the dermis obtained from the abdomen or buttock showed such a yellowish discoloration. The upper layer of the dermis that revealed the yellowish color showed elastosis whose elastic fibers were found to colocalize with carbonyl protein as detected by a labeled hydrazide, as well as by an immunohistochemical examination using the antibody against acrolein adduct. Experimental induction of carbonyl modification in a dermis model in vitro by a long-term treatment with acrolein or 4-hydroxynonenal was found to show the appearance of the yellowish change which was also proven by an increase in b* value of colorimetry. It was more pronounced than that induced by glycation. CONCLUSION: Our present results strongly suggest that carbonyl modification of the dermal protein is involved in the production of the yellowish color change that is noted in the photo-aged facial skin.

UV B-irradiation enhances the racemization and isomerizaiton of aspartyl residues and production of Nε-carboxymethyl lysine (CML) in keratin of skin.

UV-B irradiation is one of the risk factors in age-related diseases. We have reported that biologically uncommon D-ß-Asp residues accumulate in proteins from sun-exposed elderly human skin. A previous study also reported that carboxymethyl lysine (CML; one of the advanced glycation end products (AGEs)) which is produced by the oxidation of glucose and peroxidation of lipid, also increases upon UV B irradiation. The formation of D-ß-Asp and CML were reported as the alteration of proteins in UV B irradiated skin, independently. In this study, in order to clarify the relationship between the formation of D-ß-Asp and CML, immunohistochemical analysis using anti-D-ß-Asp containing peptide antibodies and anti-CML antibodies was performed in UV B irradiated mice. Immunohistochemical analyses clearly indicated that an anti-D-ß-Asp containing peptide antibody and anti-CML antibody reacted at a common area in UV B irradiated skin. Western blot analyses of the proteins isolated from UV B irradiated skin demonstrated that proteins of 50-70 kDa were immunoreactive towards antibodies for both D-ß-Asp containing peptide and CML. These proteins were identified by proteomic analysis as members of the keratin families including keratin-1, keratin-6B, keratin-10, and keratin-14.

Collagen-derived dipeptide, proline-hydroxyproline, stimulates cell proliferation and hyaluronic acid synthesis in cultured human dermal fibroblasts.

Orally ingested collagen undergoes degradation to small di- or tripeptides, which are detected in circulating blood 2 h after ingestion. The influence of collagen-derived peptides on dermal extracellular matrix components and cell proliferation was studied using cultured human dermal fibroblasts. Of the various collagenous peptides tested here, the dipeptide proline-hydroxyproline (Pro-Hyp) enhanced cell proliferation (1.5-fold) and hyaluronic acid synthesis (3.8-fold) at a dose of 200 nmol/mL. This was concomitant with a 2.3-fold elevation of hyaluronan synthase 2 (HAS2) mRNA levels. Small interfering RNA (siRNA)-mediated knockdown of the HAS2 gene in human dermal fibroblasts inhibited Pro-Hyp-induced HAS2 mRNA transcription and cell mitotic activity. Addition of genistein or H7, a protein kinase inhibitor, abolished the Pro-Hyp-induced HAS2 mRNA stimulation. Pro-Hyp elevated phosphorylation of signal transducer and activator of transcription 3 (STAT3) within a short time period (60 min). These results suggest that Pro-Hyp stimulates both cell mitotic activity and hyaluronic acid synthesis, which is mediated by activation of HAS2 transcription.

AGE-modified collagens I and III induce keratinocyte terminal differentiation through AGE receptor CD36: epidermal-dermal interaction in acquired perforating dermatosis.

To clarify the molecular mechanism underlying the transepidermal extrusion of dermal collagen in acquired perforating dermatosis (APD) associated with diabetes mellitus and renal failure, we studied the interaction between advanced glycation end product (AGE)-modified extracellular matrix proteins and keratinocytes (KCs) in a cell culture system. The expression of involucrin (INV) and keratin 10 was significantly enhanced in normal human KCs grown on AGE-modified collagen I or III compared with cells grown on unmodified collagen I or III. Glycated collagens I and III preferentially induced the expression of AGE receptor CD36, but not of other AGE receptors. KCs induced to terminal differentiation demonstrated markedly elevated CD36 expression. Glycated collagen I- and III-induced INV expression was partially blocked by the anti-CD36 antibody (Ab). These substrates also induced epidermal matrix metalloproteinase 9 (MMP-9) expression. Lesional skin from APD patients reacted moderately or strongly with the anti-CD36 Ab as well as the anti-MMP-9 Ab in the epidermal cells surrounding the collagenous materials being eliminated. These results suggest that exposing KCs to AGE-modified interstitial collagen (types I and III) by scratching induces terminal differentiation of KCs via the AGE receptor (CD36), leading to the upward movement of KCs together with glycated collagen.

Reciprocal regulation of LOX and LOXL2 expression during cell adhesion and terminal differentiation in epidermal keratinocytes.

BACKGROUND: Classical lysyl oxidase (LO) is involved in the stabilization and repair of extracellular matrix by the oxidization of lysine residues in collagen and elastin. Five genetically distinct species of LOs (LOX and LOXL1-4) have been identified, but their functions remain unclear. OBJECTIVES: To investigate the regulation of LOs during differentiation and cell adhesion of cultured keratinocytes. METHODS: LO mRNA and polypeptides levels in the suspension and adhesive cultures were measured using real-time PCR, immunoblot and immunofluorescence assays. Localization of LOX, LOXL1 and LOXL2 gene transcripts in normal epidermis was assessed by in situ hybridization. RESULTS: In the epidermis and cultured keratinocytes, LOX, LOXL1 and LOXL2 mRNA levels were predominant, and LOXL3 and LOXL4 were minor components. When cultured keratinocytes were induced to terminal differentiation, LOX expression increased 12-fold and LOXL2 expression decreased 0.1-fold, while LOXL1 mRNA level was essentially unchanged. When growth-arrested cells were allowed to adhere to extracellular matrices, LOXL2 mRNA level was stimulated 7-fold by fibronectin or type IV collagen substrate, whereas LOX mRNA level was decreased 0.1-fold by all substrates tested. Reciprocal regulation of LOX and LOXL2 expression during differentiation and adhesion was confirmed by immunoblot analysis and double immunofluorescent observation of cultured cells using anti-LOX and anti-LOXL2 antibodies. In situ hybridization analysis of normal epidermis revealed LOXL2 mRNA mainly in the lower epidermis, LOX mRNA in the upper layer of epidermis and LOXL1 throughout the epidermis. CONCLUSION: LOX expression in cultured keratinocytes is related to keratinization whereas LOXL2 expression is related to cell-matrix interaction.