Graphene delamination from chemical vapor deposited turbostratic multilayer graphene for TEM analysis.

Turbostratic multilayer graphene (MLG) is of great interest due to its unique electronic properties resulting from a linear band dispersion at the K point, which is similar to that of single-layer graphene. The band structure is derived from the stacking structure of turbostratic MLG where graphene layers have random in-plane rotations with respect to each other. Although wafer-scale growth of turbostratic MLG has been demonstrated, the crystallinity of individual graphene layers is still challenging to investigate. In this study, we present a new approach to reveal the grain structure of turbostratic MLG by transmission electron microscopy (TEM) observation. Mechanical delamination is demonstrated for the chemical vapor deposited MLG to peel off the topmost graphene layers by using a polydimethylsiloxane sheet. Micrometer-scale patterning of the MLG prior to the delamination is found to be effective to obtain graphene films with the designed shape and arrangement. Furthermore, the delaminated graphene films are successfully transferred onto a TEM grid, enabling us to estimate the grain size of the turbostratic MLG. This method is potentially applicable for not only preparing samples but also fabricating vertically stacked heterostructure devices using 2D materials.

Inhibitory Effects of Saururus chinensis Extract on Receptor for Advanced Glycation End-Products-Dependent Inflammation and Diabetes-Induced Dysregulation of Vasodilation.

Advanced glycation end-products (AGEs) and the receptor for AGEs (RAGE) are implicated in inflammatory reactions and vascular complications in diabetes. Signaling pathways downstream of RAGE are involved in NF-κB activation. In this study, we examined whether ethanol extracts of Saururus chinensis (Lour.) Baill. (SE) could affect RAGE signaling and vascular relaxation in streptozotocin (STZ)-induced diabetic rats. Treatment with SE inhibited AGEs-modified bovine serum albumin (AGEs-BSA)-elicited activation of NF-κB and could compete with AGEs-BSA binding to RAGE in a dose-dependent manner. Tumor necrosis factor-α (TNF-α) secretion induced by lipopolysaccharide (LPS)-a RAGE ligand-was also reduced by SE treatment in wild-type Ager+/+ mice as well as in cultured peritoneal macrophages from Ager+/+ mice but not in Ager-/- mice. SE administration significantly ameliorated diabetes-related dysregulation of acetylcholine-mediated vascular relaxation in STZ-induced diabetic rats. These results suggest that SE would inhibit RAGE signaling and would be useful for the improvement of vascular endothelial dysfunction in diabetes.

Dual Nature of RAGE in Host Reaction and Nurturing the Mother-Infant Bond.

Non-enzymatic glycation is an unavoidable reaction that occurs across biological taxa. The final products of this irreversible reaction are called advanced glycation end-products (AGEs). The endogenously formed AGEs are known to be bioactive and detrimental to human health. Additionally, exogenous food-derived AGEs are debated to contribute to the development of aging and various diseases. Receptor for AGEs (RAGE) is widely known to elicit biological reactions. The binding of RAGE to other ligands (e.g., high mobility group box 1, S100 proteins, lipopolysaccharides, and amyloid-ß) can result in pathological processes via the activation of intracellular RAGE signaling pathways, including inflammation, diabetes, aging, cancer growth, and metastasis. RAGE is now recognized as a pattern-recognition receptor. All mammals have RAGE homologs; however, other vertebrates, such as birds, amphibians, fish, and reptiles, do not have RAGE at the genomic level. This evidence from an evolutionary perspective allows us to understand why mammals require RAGE. In this review, we provide an overview of the scientific knowledge about the role of RAGE in physiological and pathological processes. In particular, we focus on (1) RAGE biology, (2) the role of RAGE in physiological and pathophysiological processes, (3) RAGE isoforms, including full-length membrane-bound RAGE (mRAGE), and the soluble forms of RAGE (sRAGE), which comprise endogenous secretory RAGE (esRAGE) and an ectodomain-shed form of RAGE, and (4) oxytocin transporters in the brain and intestine, which are important for maternal bonding and social behaviors.

Effect of Edge Functionalization on the Bottom-Up Synthesis of Nano-Graphenes.

We demonstrate the effect of edge functionalization on the on-surface Ullmann coupling of nano-carbon materials. Unlike 10,10'-Dibromo-9,9'-bianthryl (DBBA), which is widely known to form anthracene polymers and armchair-edge graphene nanoribbons on Au(111), newly-developed precursor named 5-bromo-11(10-bromoanthracene-9-yl)anthra[2,3-b : 7,6-b']dithiophene (BABAT) with isomers, which has similar structure as DBBA with one anthracene substituted with anthradithiophene, was found to make intramolecular C-C bonding instead of long anthracene polymers after annealing at 200 °C on Au(111). The mechanism was investigated using first-principle density functional theory, which revealed that on-surface polymerization is not kinetically preferred in case of BABAT. The reaction rate of intramolecular C-C bonding of BABAT is ∼206 times faster than that of DBBA. The intramolecular C-C bonding in DBBA biradicals, on the other hand, do not take place because of faster reverse reaction. By referring to electron density of BABAT biradicals, it was concluded that thiophene functionalization modifies distribution of electron density in BABAT radicals and facilitates electrophilic addition, leading to intramolecular C-C bonding after 200 °C annealing. These results indicate that the design of radical moiety is particularly important in the on-surface Ullmann-type coupling.

Open Label Trial of the Efficacy and Safety Profile of Rikkunshito used for the Treatment of Gastrointestinal Symptoms in Patients with Parkinson's Disease: A Pilot Study.

BACKGROUND: Patients with Parkinson's disease (PD) usually experience distress related not only to motor dysfunction, but also to nonmotor symptoms, including gastrointestinal dysfunction. OBJECTIVE: The purpose of this pilot study was to evaluate the efficacy and safety profile of a traditional Japanese medicine, rikkunshito (RKT), used for the treatment of gastrointestinal symptoms, associated with anorexia and dyspepsia, in patients with PD. METHODS: Patients were randomly assigned to either Group A (4-week treatment period with 7.5 g/d RKT followed by a 4-week off-treatment period) or Group B (4-week off-treatment period followed by a 4-week treatment period with 7.5 g/d RKT). Appetite, quality of life for gastrointestinal symptoms, and depression were assessed using a visual analog scale, the Gastrointestinal Symptom Rating Scale and the Self-Rating Depression Scale, respectively. The gastric emptying examination and assay of plasma acylated ghrelin level were performed using the 13C-acetate breath test and commercially available assay kits, respectively. RESULTS: RKT treatment produced a significant increase in the appetite score (1.84 [2.34]; P < 0.05), compared to a decrease in the score over the off-treatment period (-1.36 [2.94]). The mean score for abdominal pain, on the Gastrointestinal Symptom Rating Scale, and for self-reported depression, on the Self-Rating Depression Scale, also decreased significantly with RKT treatment (P < 0.05), compared with the off-treatment period scores. No effect of RKT on plasma acylated ghrelin level and rate of gastric emptying was identified. CONCLUSIONS: RKT may improve anorexia in patients with PD. The positive effects of RKT on depression and anorexia may improve the overall quality of life of these patients. The benefits of RKT identified in our pilot study will need to be confirmed in a randomized, double-blind, controlled trial. UMIN Clinical Trial Registry identifier: UMIN000009626.

Antibacterial drug treatment increases intestinal bile acid absorption via elevated levels of ileal apical sodium-dependent bile acid transporter but not organic solute transporter α protein.

Antibacterial drug treatment increases the bile acid pool size and hepatic bile acid concentration through the elevation of hepatic bile acid synthesis. However, the involvement of intestinal bile acid absorption in the increased bile acid pool size remains unclear. To determine whether intestinal bile acid absorption contributes to the increased bile acid pool in mice treated with antibacterial drugs, we evaluated the levels of bile acid transporter proteins and the capacity of intestinal bile acid absorption. Ileal apical sodium-dependent bile acid transporter (ASBT) mRNA and protein levels were significantly increased in ampicillin (ABPC)-treated mice, whereas organic solute transporter α (OSTα) mRNA levels, but not protein levels, significantly decreased in mice. Similar alterations in the expression levels of bile acid transporters were observed in mice treated with bacitracin/neomycin/streptomycin. The capacity for intestinal bile acid absorption was evaluated by an in situ loop method. Increased ileal absorption of taurochenodeoxycholic acid was observed in mice treated with ABPC. These results suggest that intestinal bile acid absorption is elevated in an ASBT-dependent manner in mice treated with antibacterial drugs.

Comparison of Postoperative Stress Urinary Incontinence between Anteroposterior Dissection and Modified Gilling Method in Holmium Laser Enucleation of the Prostate.

PURPOSE: Few studies have evaluated the usefulness of anteroposterior dissection holmium laser enucleation of the prostate (HoLEP). Thus, this study investigated the incidence of stress urinary incontinence (SUI) after HoLEP and usefulness of anteroposterior dissection HoLEP in preventing postoperative SUI. MATERIALS AND METHODS: In total, 288 patients who underwent HoLEP performed by a single experienced surgeon between May 2014 and September 2021 were enrolled. Furthermore, 134 patients underwent retrograde dissection using the modified Gilling method (surgery 1) and 154 patients underwent anteroposterior dissection HoLEP (surgery 2). The risk factors for SUI, as well as the rates of SUI improvement for the two surgical procedures, were evaluated. RESULTS: Postoperative SUI was observed in 58 (20.1%) of 288 patients, of whom, 48 (82.8%) recovered continence within 6 months. Ten patients (17.2%) required more than 6 months to recover continence. SUI incidence 1 month after HoLEP was 29.9% (40/134 patients) for surgery 1 and 11.7% (18/154 patients) for surgery 2; a statistically significant difference was observed between the two groups (odds ratio [OR], 0.311; 95% confidence interval [CI], 0.168-0.575; p < 0.001). In addition, surgery 2 was significantly associated with early recovery from SUI compared with surgery 1 (stratified hazard ratio, 0.782; 95% CI, 0.615------0.995; p < 0.001). The multivariable analysis demonstrated that only surgical procedure (OR, 0.350; 95%CI, 0.168-0.732; p=0.005) was an independent predictor of SUI.- Conclusion: We reaffirmed that anteroposterior dissection HoLEP is a useful procedure for reducing the risk of postoperative SUI and early recovery of urinary continence.

Anisotropic graphene growth accompanied by step bunching on a dynamic copper surface.

We investigated the initial stage of chemical vapor deposition graphene growth on Cu film at low pressure, where Cu evaporation intensively occurs. Surface steps on the Cu surface were found to be the nucleation sites of graphene islands and to affect the subsequent growth. For the first time, we observed anisotropic graphene growth on the Cu surface accompanied by morphological changes, resulting in an arrayed graphene ribbon formation. The resultant surface morphology is attributed to step bunching during growth. Detailed analyses suggest that the graphene arrays, which were preferentially formed along the steps, served as partial shields of the Cu surface, preventing step-flow-like Cu atom diffusion and evaporation at the growth site. As a result, the growth locations acted as a pinning site of the step motion, leading to step bunching. Such selective growth by using surface morphology has the potential to control not only the nucleation site but also the geometry of graphene for tailoring graphene-based nanomaterials such as nanoribbons and quantum dots.

Preoperative neoadjuvant chemoradiotherapy provides borderline resectable thoracic esophageal cancer with equivalent treatment results as clinically T3 thoracic esophageal cancer.

Aim: Because the optimal treatment strategy for borderline resectable (cT3br) thoracic esophageal cancer patients remains unclear, it is of great interest whether preoperative neoadjuvant therapy for cT3br could achieve results comparable to those seen with resectable T3 cancer (cT3r). We speculated that preoperative neoadjuvant chemoradiotherapy (NACRT) would be particularly effective in cT3br thoracic esophageal cancer patients and compared to cT3br and cT3r. Methods: Of 186 cT3 thoracic esophageal cancer patients treated with intended NACRT, 162 received radical esophagectomy. More than 97% were squamous cell carcinomas. Patients were partitioned into two groups according to whether invasion of adjacent organs was suspected (cT3br and cT3r). Treatment outcomes and survival were analyzed. Results: Sixty-eight patients (36.6%) were classified as cT3br and 118 (63.4%) as cT3r. The cT3br group had significantly more tumors in the upper and middle mediastinum (p < 0.0001) and more cases with cM1 (lymph node) (p = 0.0104) than the cT3r group. In addition, the cT3br patients receiving esophagectomy exhibited a significantly lower pathological complete response rate than the cT3r patients (p = 0.0374). However, the R0 resection rate did not differ between the cT3br and cT3r patients (p = 0.0978), and the two groups treated with intended NACRT had similar 5-year overall (OS) and disease-specific survival (DSS) (p = 0.3831 and p = 0.9020). In addition, the incidence and patterns of recurrence did not differ between the cT3br and cT3r patients receiving esophagectomy (p = 0.8109 and p = 0.3128). Conclusions: Preoperative neoadjuvant chemoradiotherapy appears to be a promising treatment for patients with borderline resectable thoracic esophageal squamous cell carcinoma.

Selective graphene formation on copper twin crystals.

Selective graphene growth on copper twin crystals by chemical vapor deposition has been achieved. Graphene ribbons can be formed only on narrow twin crystal regions with a (001) or high-index surface sandwiched between Cu crystals having (111) surfaces by tuning the growth conditions, especially by controlling the partial pressure of CH(4) in Ar/H(2) carrier gas. At a relatively low CH(4) pressure, graphene nucleation at steps on Cu (111) surfaces is suppressed, and graphene is preferentially nucleated and formed on twin crystal regions. Graphene ribbons as narrow as ~100 nm have been obtained in experiments. The preferential graphene nucleation and formation seem to be caused primarily by a difference in surface-dependent adsorption energies of reactants, which has been estimated by first principles calculations. Concentrations of reactants on a Cu surface have also been analyzed by solving a diffusion equation that qualitatively explains our experimental observations of the preferential graphene nucleation. Our findings may lead to self-organizing formation of graphene nanoribbons without reliance on top-down approaches in the future.

Epitaxial Growth of SnS2 Ribbons on a Au-Sn Alloy Seed Film Surface.

Two-dimensional metal chalcogenide film has attracted considerable interest for its use as an emerging device material for nanoelectronics. The film has been synthesized by various methods such as chemical vapor deposition, molecular beam epitaxy, and thermal vapor sulfurization. In this study, we took a new approach to synthesize tin disulfide (SnS2) by using Au-Sn alloy film as a metal seed deposited on a sapphire substrate. Multilayer SnS2 films were formed in a ribbon shape on (111)-oriented Au film and were aligned in the directions of threefold rotational symmetry. Furthermore, the SnS2 was found to have an epitaxial relationship relative to the Au film and the sapphire substrate as follows: SnS2[2̅110] || Au[101̅] || Al2O3[011̅0]. The segregation of grains consisting of a Sn-rich phase on the Au film surface and the subsequent sulfurization of these grains can be the key to the epitaxial SnS2 ribbon formation.

Highly Sensitive NO2 Detection by TVS-Grown Multilayer MoS2 Films.

Two-dimensional layered materials have been investigated for sensor applications over the last decade due to their very high specific surface area and excellent electrical characteristics. Although grain boundaries are inevitably present in polycrystalline-layered materials used for real applications, few studies have investigated their effects on sensing properties. In this study, we demonstrate the growth of two distinct MoS2 films that differ in grain size by means of chemical vapor deposition (CVD) and thermal vapor sulfurization (TVS) methods. Transistor-based sensors are fabricated using these films, and their NO2 sensing properties are evaluated. The adsorption behavior of NO2 on MoS2 is considered in terms of the Langmuir isotherm, and the experimental results can be well fitted by the equation. The CVD-grown film exhibits electrical properties 1-2 orders of magnitude superior to those of the TVS-grown one, which is attributed to the large grain size of the CVD-grown film. In contrast, the sensitivity to NO2 is unexpectedly found to be higher in the TVS-grown film and is of the same order of a previously reported record value. Transmission electron microscopy observations suggest that the TVS-grown film consists of multiple rotationally oriented grains that are connected by mirror twin grain boundaries. Theoretical calculation results reveal that the adsorption of NO2 on the grain boundary that we modeled is equal to that on the ideal basal plane surface of MoS2. In addition, the porous structure in the TVS-grown film may also contribute to enhancing the sensor response to NO2. This study suggests that a highly sensitive MoS2 sensor can also be fabricated by using a polycrystalline film with small grain size, which can possibly be applied to other two-dimensional materials.

Laparoscopic retroperitoneal lymph node dissection versus open retroperitoneal lymph node dissection for testicular cancer: A comparison of clinical and perioperative outcomes.

Objective: This study was performed to evaluate the clinical and perioperative outcomes of laparoscopic retroperitoneal lymph node dissection (L-RPLND) and open retroperitoneal lymph node dissection (O-RPLND) performed by one surgeon at a single center. Methods: We evaluated 30 patients with stage IIA germ cell tumors who underwent retroperitoneal lymph node dissection (15 underwent L-RPLND and 15 underwent O-RPLND) at our institution between April 1, 2010 and March 31, 2018. The clinical parameters were compared between patients who underwent L-RPLND using the retroperitoneal approach and those who underwent O-RPLND using the transperitoneal approach. There were no significant differences in the background characteristics of the two groups except for the median follow-up duration (46 months for L-RPLND and 71 months for O-RPLND, p=0.02). Results: L-RPLND was associated with a shorter mean operative time (mean 222 min for L-RPLND vs. 453 min for O-RPLND, p<0.001). There was significantly less blood loss during surgery in the L-RPLND group compared to the O-RPLND group (mean 165 mL for L-RPLND vs. 403 mL for O-RPLND, p<0.001). Parameters related to postoperative recovery were significantly better for the L-RPLND group than for the O-RPLND group. There were no differences in the histopathological characteristics between the two groups. No patients in either group exhibited disease recurrence. Conclusion: Patients who underwent L-RPLND had more rapid recovery, and shorter hospital stay compared to those who underwent O-RPLND; complications were comparable between the two groups. L-RPLND is an efficient procedure with the benefits of minimally invasive surgery.

Immunomagnetic quantification of circulating tumor cells in patients with urothelial cancer.

OBJECTIVES: To evaluate the relationship between circulating tumor cells (CTC) and clinical parameters in metastatic urothelial cancer (UC). METHODS: CTC were enumerated with the CellSearch System, which was developed using an EpCAM antibody-based immunomagnetic capture and automated staining methodology. UC cell lines (RT4, T24, TCC, UMUC3 and 253J) and mixed blood from healthy males were analyzed. Blood samples from 16 patients without metastatic UC and 20 patients with metastatic UC were also analyzed. RESULTS: The accuracy and reliability of the assay were determined using spiked UC cells (RT4 and T24), which showed a strong linear correlation (r = 0.99) and recovery rate of 94% +/- 5% and 84% +/- 6%, respectively. Three UC cell lines (TCC, UMUC3 and 253J) tested negative. The 16 patients without metastatic UC tested negative as well. Eleven (55%) patients with metastatic UC tested positive for at least one CTC. Seven (35%) had two or more CTC. Significantly more CTC were seen in patients with two or more sites of metastasis than those with one site of metastasis (P = 0.004). CONCLUSIONS: Based on these findings, CTC could represent a potential marker to monitor the response to chemotherapy in patients with metastatic UC.

Vacancy-Assisted Selective Detection of Low-ppb Formaldehyde in Two-Dimensional Layered SnS2.

A two-dimensional (2D) layered SnS2 film synthesized by the thermal-chemical vapor deposition method is utilized for detecting formaldehyde (HCHO), which causes a sick building syndrome. A back-gated field-effect transistor (FET)-based SnS2 sensor successfully detects HCHO with concentrations down to 1 ppb in a nitrogen atmosphere. Sensing measurements performed under dry air conditions also exhibit a clear response to 20 ppb of HCHO, which is more sensitive than the previously reported sensors based on other 2D-layered materials. Moreover, it is found that the sensor possesses a high selectivity for HCHO over other organic species. Theoretical calculations suggest that native sulfur vacancies existing in n-type SnS2 crystals play an important role in HCHO detection. Actually, oxygen atoms that are unexpectedly detached from HCHO molecules are found to fill the vacancies, giving rise to p-type doping in SnS2. As a result, decrease in the drain current of SnS2-FET can be found as a signal of HCHO detection. Furthermore, considering the future mass-production of sensors, we demonstrate large-scale growth of the SnS2 film by means of magnetron-sputtering deposition and subsequent annealing in a diluted hydrogen sulfide atmosphere. The sputtered film is also found to exhibit a good sensing ability to HCHO.

[Comparison of clinical results between TUR-P and holmium laser enucleation of the prostate (HoLEP) based on the initial experience].

OBJECTIVE: We compared the surgical results between holmium laser enucleation of the prostate (HoLEP) and transurethral resection of the prostate (TUR-P) for the treatment of men with benign prostatic hyperplasia (BPH). METHODS: A total of 87 patients with symptomatic BPH were analysed. HoLEP was performed on 46 men (mean age 68.2 +/- 7.5 years old) from December 2005 to February 2007, and TUR-P was performed on 41 men (mean age 69.2 +/- 7.3 years old) from April 2004 to March 2006. RESULTS: Both groups were comparable in terms of age, pre-operative IPSS, QOL index, urodynamic study results and prostate volume. During operation, decrease in hemoglobin was less in the HoLEP group than in the TUR-P group (1.15 +/- 1.2 vs 1.91 +/- 1.3 g/dl p < 0.05). The operation time was significantly longer in the HoLEP group than in the TUR-P group (161.9 +/- 65.0 vs. 118.3 +/- 36.9 minutes p < 0.001). Mean resected weight was 29.3 +/- 13.3 g (10-55) in the TUR-P group and 34.8 +/- 33.4 g (5-148) in the HoLEP group (p = 0.337). The catheterization period (52.1 +/- 29.6 vs. 115.2 +/- 27.5 hour p < 0.001) and hospital stay (6.6 +/- 2.3 vs. 9.4 +/- 2.2 days p < 0.001) were significantly shorter in the HoLEP group than in the TUR-P group. At follow up, Qmax, average flow rate and post void residual urine (PVR) in two groups improved significantly, and these parameters were not significantly different between the groups after 3 months. CONCLUSIONS: Both TUR-P and HoLEP were effective in relieving BOO. The estimated blood loss, a catheterization time and hospitalization were less or shorter in the HoLEP group. HoLEP may be a good alternative to the conventional transurethral electrocautery resection of the prostate for symptomatic BPH.

[Urachal anomalies and tumor: clinical investigation of 14 cases].

Diseases associated with persistent urachus are relatively rare. During the past 9-year period, there have been 14 patients with urachal disease consisting of 10 with urachal abscess and 4 with urachal cancer. The 10 patients with urachal abscess consisted of 7 males and 3 females aged 19-77 years (mean, 46 years). The 4 patients with urachal cancer consisted of 2 males and 2 females aged 48-81 years (mean, 57 years). As symptoms, lower abdominal pain was frequently observed in the patients with persistent urachus with abscess and gross hematuria in those with urachal cancer. Echo and magnetic resonance imaging (MRI) were useful for visualizing the lesion. Computed tomogtaphic (CT) scanning could not visualize the lesion in 2 patients. Nine patients underwent MRI, which visualized the lesion in all of them. As urachal abscess, an umbilical fistula was observed in 3 patients, urachal cyst in 4, and urachal diverticulum in 1. The preoperative diagnosis was urachal cancer in 6 patients, and pathological examination showed 4 patients with adenocarcinoma, 1 with inflammatory granuloma, and 1 with pseudosarcoma. Urachal abscess was treated by resection of the abscess in 6 patients, transurethral resection in 1, and resection of the umbilicus and urachus and total cystectomy in the other. Of the patients with urachal cancer, 1 underwent total cystectomy and the other 3 underwent total urachal resection and partial cystectomy. In 2 patients with persistent urachus with abscess, the differentiation between abscess and malignant tumor was difficult.

Ileal apical sodium-dependent bile acid transporter protein levels are down-regulated through ubiquitin-dependent protein degradation induced by bile acids.

The ileal apical sodium-dependent bile acid transporter (ASBT or SLC10A2) has a crucial role in intestinal bile acid absorption. We previously reported that enterobacteria-mediated bile acid conversion was involved in the alteration of ileal ASBT expression levels. In the present study, to investigate the hypothesis that ileal ASBT protein levels are post-translationally regulated by enterobacteria-associated bile acids, alteration of ileal ASBT protein levels was analysed in mice 12 h and 24 h after anti-bacterial drug ampicillin (ABPC) treatment (100 mg/kg, single shot) that altered bile acid composition in the intestinal lumen. In ABPC-treated mice, enterobacteria-biotransformed bile acid, taurodeoxycholic acid (TDCA) and cholic acid (CA) levels were decreased, whereas taurocholic acid (TCA) and tauro-ß-muricholic acid levels were increased in the intestinal lumen. Ileal ASBT protein levels in brush-border membrane vesicles (BBMVs), but not ileal Asbt mRNA levels, were significantly increased in the ABPC-treated mice, and the extent of ubiquitination of the ileal ASBT protein was reduced in the ABPC-treated mice. Treatment of ABPC-pretreated mice with CA or TDCA, but not TCA, significantly decreased ileal ASBT protein levels and increased the extent of ubiquitination of ileal ASBT protein. Treatment of mice with the lysosome inhibitor, chloroquine, or the proteasome inhibitor, MG132, increased ileal ASBT protein levels in BBMVs. CA-mediated reduction of ASBT protein levels in the ABPC-pretreated mice was attenuated by co-treatment with chloroquine or MG132. These results suggest that ileal ASBT protein is degraded by a ubiquitin-dependent pathway in response to enterobacteria-associated bile acids.

Epitaxial silicon oxynitride layer on a 6H-SiC(0001) surface.

Hydrogen-gas etching of a 6H-SiC(0001) surface and subsequent annealing in nitrogen atmosphere leads to the formation of a silicon oxynitride (SiON) epitaxial layer. A quantitative low-energy electron diffraction analysis revealed that the SiON layer has a hetero-double-layer structure: a silicate monolayer on a silicon nitride monolayer via Si-O-Si bridge bonds. There are no dangling bonds in the unit cell, which explains the fact that the structure is robust against air exposure. Scanning tunneling spectroscopy measured on the SiON layer shows a bulk SiO2-like band gap of approximately 9 eV. Great potential of this new epitaxial layer for device applications is described.