Free cholesterol accumulation in hepatic stellate cells: mechanism of liver fibrosis aggravation in nonalcoholic steatohepatitis in mice

Although nonalcoholic steatohepatitis (NASH) is associated with hypercholesterolemia, the underlying mechanisms of this association have not been clarified. We aimed to elucidate the precise role of cholesterol in the pathophysiology of NASH. C57BL/6 mice were fed a control, high-cholesterol (HC), methionine-choline-deficient (MCD), or MCD+HC diet for 12 weeks or a control, HC, high-fat (HF), or HF+HC diet for 24 weeks. Increased cholesterol intake accelerated liver fibrosis in both the mouse models without affecting the degree of hepatocellular injury or Kupffer cell activation. The major causes of the accelerated liver fibrosis involved free cholesterol (FC) accumulation in hepatic stellate cells (HSCs), which increased Toll-like receptor 4 protein (TLR4) levels through suppression of the endosomal-lysosomal degradation pathway of TLR4, and thereby sensitized the cells to transforming growth factor (TGF)β-induced activation by down-regulating the expression of bone morphogenetic protein and activin membrane-bound inhibitor. Mammalian-cell cholesterol levels are regulated by way of a feedback mechanism mediated by sterol regulatory element-binding protein 2 (SREBP2), maintaining cellular cholesterol homeostasis. Nevertheless, HSCs were sensitive to FC accumulation because the high intracellular expression ratio of SREBP cleavage-activating protein (Scap) to insulin-induced gene (Insig) disrupted the SREBP2-mediated feedback regulation of cholesterol homeostasis in these cells. HSC activation subsequently enhanced the disruption of the feedback system by Insig-1 down-regulation. In addition, the suppression of peroxisome proliferator-activated receptor γ signaling accompanying HSC activation enhanced both SREBP2 and microRNA-33a signaling. Consequently, FC accumulation in HSCs increased and further sensitized these cells to TGFβ-induced activation in a vicious cycle, leading to exaggerated liver fibrosis in NASH.

CONCLUSION

These characteristic mechanisms of FC accumulation in HSCs are potential targets to treat liver fibrosis in liver diseases including NASH.

The influence of serum sodium concentration on prognosis in resected non-small cell lung cancer

BACKGROUND

Hyponatremia is the most common electrolyte disorder and is a negative prognostic factor in several kinds of cancer. However, few reports have referred to hyponatremia in non-small cell lung cancer (NSCLC). In the present study, the authors examined the influence of preoperative serum sodium concentration on survival in completely resected NSCLC.

METHODS

A total of 386 completely resected NSCLC patients were retrospectively analyzed.

RESULTS

Kaplan-Meier survival curves showed that serum sodium concentration was a significant prognostic factor, and the log-rank statistical value was maximum (9.173, p = 0.002) when the cutoff value of serum sodium concentration was 139 mEq/L. The overall 5-year survival rate of the high-serum sodium concentration group (> 139 mEq/L) was 74.8% and that of the low-serum sodium concentration group (≤ 139 mEq/L) was 59.7%. Clinicopathological factors showed significant differences between the two groups for leukocyte count, neutrophil count, C-reactive protein, tumor size, and pleural invasion.

CONCLUSIONS

Low-serum sodium concentration, which was associated with tumor status and inflammation, had negative prognostic influence in completely resected NSCLC.

C-C motif chemokine receptor 9 positive macrophages activate hepatic stellate cells and promote liver fibrosis in mice

Chemokine receptors mediate migration of immune cells into the liver, thereby promoting liver inflammation. C-C motif chemokine receptor (CCR) 9(+) macrophages are crucial in the pathogenesis of acute liver inflammation, but the role and underlying mechanisms of this macrophage subset in chronic liver injury and subsequent liver fibrosis are not fully understood. We confirmed that tumor necrosis factor alpha (TNF-α)-producing CCR9(+) macrophages accumulated during the initiation of carbon tetrachloride (CCl4 )-induced liver injury, and CCR9 deficiency attenuated the degree of liver damage. Accumulation of CCR9(+) macrophages persisted prominently during the process of liver fibrosis induced by repetitive CCl4 or thioacetamide (TAA)/leptin administration. Increased CCR9 expression was also found on activated hepatic stellate cells (HSCs). Importantly, experimental liver fibrosis was significantly ameliorated in CCR9(-/-) mice compared with wild-type (WT) mice, assessed by α-smooth muscle actin (α-SMA) immunostain, Sirius red staining, and messenger RNA (mRNA) expression levels of α-SMA, collagen 1α1, transforming growth factor (TGF)-β1, and tissue inhibitor of metalloproteinase (TIMP)-1. Accumulated CD11b(+) macrophages in CCl4 -treated WT mice showed marked increases in TNF, NO synthase-2, and TGF-β1 mRNA expression compared with CCR9(-/-) mice, implying proinflammatory and profibrogenic properties. Hepatic CD11b(+) macrophages from CCl4 -treated WT mice (i.e., CCR9(+) macrophages), but not CD8(+) T lymphocytes or non-CD11b(+) cells, significantly activated HSCs in vitro compared with those from CCR9(-/-) mice. TNF-α or TGF-β1 antagonism attenuated CCR9(+) macrophage-induced HSC activation. Furthermore, C-C motif chemokine ligand (CCL) 25 mediated migration and, to a lesser extent, activation of HSCs in vitro.

CONCLUSION

Accumulated CD11b(+) macrophages are critical for activating HSCs through the CCR9/CCL25 axis and therefore promote liver fibrosis. CCR9 antagonism might be a novel therapeutic target for liver fibrosis.

Applicability of second-generation colon capsule endoscope to ulcerative colitis: a clinical feasibility study

BACKGROUND AND AIM

Colon capsule endoscopy has already been used for colon visualization and detection of polyps but its applicability to inflammatory bowel disease is still unconfirmed. The aim of this study was to assess the feasibility of evaluating the severity of mucosal inflammation in patients with ulcerative colitis (UC) using a second-generation colon capsule endoscope (CCE-2).

METHODS

Forty patients with histological confirmed diagnosis of UC were enrolled. Low-volume (2 L) polyethylene glycol solution with prokinetics (mosapride citrate and metoclopramide) regimen was used for the bowel preparation. In Phase 1, consisting of 10 patients, to confirm appropriate CCE-2 bowel preparation for UC. In Phase 2, consisting of 30 patients, CCE-2 was performed with a fixed bowel preparation regimen. CCE-2 findings were recorded for 8 h starting from capsule ingestion and conventional colonoscopy was subsequently performed on the same day. CCE-2 procedure completion rate and the colon cleansing level with a 4-point grading scale (poor, fair, good, and excellent) were evaluated in Phase 2. Correlations between Matts endoscopic scores as judged by CCE-2 and conventional colonoscopy were calculated.

RESULTS

CCE-2 procedure was completed within 8 h in 69% of the patients. The proportion of patients with good or excellent cleansing level was below 50%. However, Matts endoscopic scores determined by CCE-2 showed a strong correlation with scores obtained by conventional colonoscopy (average ρ = 0.797).

CONCLUSIONS

Although modifications in bowel preparation are needed, CCE-2 might be feasible for assessing the severity of mucosal inflammation in patients with UC.

Intrapulmonary bronchogenic cyst in the thoracic cavity: a case report

This case report presents an intrapulmonary bronchogenic cyst exhibiting a unique shape. The patient was a 19-year-old man who had been diagnosed with a posterior mediastinal tumor by computed tomography and magnetic resonance imaging, 2 years previously. The imaging revealed that the tumor was located on the left side of the posterior mediastinum and was 45 × 25 mm in size. As the size and shape of the tumor did not change in the 2 years after its detection, surgical extraction was planned. Preoperative diagnosis was, firstly, a neurogenic tumor originating in the posterior mediastinum.Surgical findings revealed that the tumor formed a bridge between the visceral pleura of the left lower lobe and the chest wall, and most of the tumor was located in the thoracic cavity. Pathological diagnosis was intrapulmonary bronchogenic cyst. An intrapulmonary bronchogenic cyst with a unique shape, as observed in this case, is very rare.Although preoperative imaging could predict the tumor size, it could not confirm where the tumor originated. Surgical resection of this type of tumor, which is diagnosed preoperatively as a posterior mediastinal tumor, is a superior strategy for precise diagnosis and treatment.

Role of enhanced visibility in evaluating polyposis syndromes using a newly developed contrast image capsule endoscope

Background/Aims

A flexible spectral imaging color enhancement system was installed in new capsule software for video capsule endoscopy. Contrast image capsule endoscopy (CICE) is a novel technology using light-emitting diodes selected for the main absorption range of hemoglobin. We assessed the feasibility and diagnostic effi cacy for small bowel surveillance in patients with polyposis syndromes.

Methods

Six patients with polyposis syndromes, four with familial adenomatous polyposis and one each with Cowden syndrome (CS) and Cronkhite-Canada syndrome (CCS) were examined using CICE. We conducted three evaluations to assess the effect on the numbers of the detected polyps; compare polyp diagnostic rates between adenoma and hamartoma; and assess polyp visibility.

Results

The numbers of detected polyps and diagnostic accuracy did not differ signifi cantly between pre-contrast and contrast images. However, 50% of the adenomatous polyps displayed enhanced visibility on contrast images. CICE contrast images exhibited clearly demarcated lesions and improved the visibility of minute structures of adenomatous polyps. Hamartomatous polyp micro-structures in patients with CS and CCS were more clearly visualized on contrast than pre-contrast images.

Conclusions

CICE is an effective tool for enhancing the visibility of polyps in patients with polyposis syndrome.

Evaluation of liver fibrosis by transient elastography using acoustic radiation force impulse: comparison with Fibroscan(®)

BACKGROUND

Accurate evaluation of liver fibrosis in patients with chronic liver damage is required to determine the appropriate treatment. Various approaches, including laboratory tests and transient elastography, have been used to evaluate liver fibrosis. Recently, transient elastography with acoustic radiation force impulse (ARFI) has been developed and applied with conventional ultrasonography. The aim of this study was to evaluate the clinical utility of transient elastography with ARFI and to compare the results with this method and those of the Fibroscan(®) procedure.

METHODS

One hundred and thirty-one patients with liver damage, who underwent liver biopsy at our department, were enrolled prospectively in this study. Elastography with ARFI (applied with ACUSON S2000(®)), and Fibroscan(®) was performed at the same time as liver biopsy. These measurements were compared with histological findings in liver biopsy specimens, and measurement accuracy was evaluated by receiver-operating characteristic analysis.

RESULTS

Elastography values with both procedures were significantly correlated with the stages of liver fibrosis and there was little difference in the results obtained using the 2 procedures. The accuracy of differential diagnosis between no fibrosis at F0 and more than F1 stage was insufficient with ARFI, but this procedure was sufficient for diagnosing advanced fibrosis. The accuracy of ARFI was almost equivalent to that of the Fibroscan(®) method. Moreover, both ARFI and Fibroscan(®) values increased in proportion to the severity of hepatic inflammation when fibrosis stage is low, but not in proportion to the severity of steatosis.

CONCLUSIONS

Transient elastography with ARFI is simple, non-invasive and useful for diagnosing the stage of fibrosis in chronic liver disease. The utility of ARFI was almost equivalent to that of the Fibroscan(®) method.

Evaluation of liver fibrosis by transient elastography using acoustic radiation force impulse: comparison with Fibroscan(®)

BACKGROUND

Accurate evaluation of liver fibrosis in patients with chronic liver damage is required to determine the appropriate treatment. Various approaches, including laboratory tests and transient elastography, have been used to evaluate liver fibrosis. Recently, transient elastography with acoustic radiation force impulse (ARFI) has been developed and applied with conventional ultrasonography. The aim of this study was to evaluate the clinical utility of transient elastography with ARFI and to compare the results with this method and those of the Fibroscan(®) procedure.

METHODS

One hundred and thirty-one patients with liver damage, who underwent liver biopsy at our department, were enrolled prospectively in this study. Elastography with ARFI (applied with ACUSON S2000(®)), and Fibroscan(®) was performed at the same time as liver biopsy. These measurements were compared with histological findings in liver biopsy specimens, and measurement accuracy was evaluated by receiver-operating characteristic analysis.

RESULTS

Elastography values with both procedures were significantly correlated with the stages of liver fibrosis and there was little difference in the results obtained using the 2 procedures. The accuracy of differential diagnosis between no fibrosis at F0 and more than F1 stage was insufficient with ARFI, but this procedure was sufficient for diagnosing advanced fibrosis. The accuracy of ARFI was almost equivalent to that of the Fibroscan(®) method. Moreover, both ARFI and Fibroscan(®) values increased in proportion to the severity of hepatic inflammation when fibrosis stage is low, but not in proportion to the severity of steatosis.

CONCLUSIONS

Transient elastography with ARFI is simple, non-invasive and useful for diagnosing the stage of fibrosis in chronic liver disease. The utility of ARFI was almost equivalent to that of the Fibroscan(®) method.

Preoperative lymphocyte count is an independent prognostic factor in node-negative non-small cell lung cancer

A number of prognostic factors have been reported in non-small cell lung cancer (NSCLC). Although lymph node metastasis is the most poorly predictive value in completely resected NSCLC, a significant number of patients have a fatal recurrence even in node-negative curative NSCLC. Recently inflammatory response has been shown as a predictive value in NSCLC. Neutrophils and lymphocytes play an important role in cancer immune response. In this study, we retrospectively examined the impact of preoperative peripheral neutrophil and lymphocyte counts on survival, and investigated the relationships of these factors to clinicopathological factors in node-negative NSCLC. A total 237 patients were evaluated. When the cut-off value of neutrophil count was 4500 mm(-3) with a maximum log-rank statistical value, overall 5-year survival rates were 79.7% for the low-neutrophil-count group and 69.5% for the high-neutrophil-count group (P=0.04). When the cut-off value of lymphocyte count was 1900 mm(-3) with a maximum log-rank statistical value, overall survival rates were 67.9% for the low-lymphocyte group and 87.7% for the high-lymphocyte group (P<0.001). High-neutrophil-counts were associated with tumor size (P=0.002) and pleural invasion (P<0.001). Low-lymphocyte-counts were correlated with vascular invasion (P=0.018) and recurrence of NSCLC (P=0.01). Multivariate analysis showed that the lymphocyte count was an independent prognostic factor (hazard ratio: 3.842; 95% confidence interval: 1.827-8.078; P<0.001), but the neutrophil count was not (P=0.185). We conclude that a peripheral lymphocyte count, which is associated with vascular invasion, is an independent prognostic factor in node-negative NCSLC.

Pulsed Laser-Induced Amorphization of Silicon Films

Amorphization of silicon films occurred through homogeneous solidification of molten silicon layers on quartz substrates induced by irradiation with a 30ns-XeCl excimer laser. The crystalline nucleation rate was obtained to be 8×1030m−3s−1. Silicon films were completely amorphized for films thinner than 18nm. Complete amorphizatoin is brought about by reduced grain size and reduced recalescence as the film thickness decreases. Recalescence was observed in situusing transient thermometry with a platinum-temperature-sensing layer when a 15nm-thick silicon film was amorphized.

XeCl Excimer Laser Annealing Used to Fabricate Poly-Si Tfts

Mo-gate n-channel poly-Si TFTs have been fabricated for the first time at a low processing temperature of 26°C. 500 to 1000A thick a-Si:H was successfully crystallized by pulsed XeCl excimer laser (308nm) annealing without heating the glass substrate. The channel mobility of the TFT was 180 cm2/V.sec when the a-Si:H was annealed at energy density of 200 mJ/cm2.

The Characteristics and Oxidation of Vapor - Liquid - Solid Grown Si Nanowires

The Vapor - Liquid - Solid (VLS ) technique allows the growth of high aspect ratio Si wires. The Si nanowires formed by this technique can be thinned down by oxidation. This approach allows the formation of very thin Si cores which may be used to research the properties of Si nanostructures. In this work the growth and oxidation of these wires is characterized.

In the growth a very thin layer of Au is deposited on a Si (111) surface, silane gas is introduced into the chamber as the Si source gas and the temperature is raised to 300 – 600°C. Initially a catalytically active Au surface phase leads to the growth of a defective epitaxial Si layer. As Au / Si molten alloy balls nucleate and grow in size to approach the threshold size for VLS wire growth, which is determined by the Gibbs - Thomson effect, the epitaxial layer growth rate decreases and a transition to Si nanowire growth occurs. The morphology and width of the wires is strongly dependent on the growth temperature and pressure. At low pressure and high temperature relatively thick well-formed wires grow straight up from the substrate surface along the [111] direction. As the temperature is decreased and the pressure is increased thinner wires (as thin as 10 nm ) grow which tend to exhibit growth defects. A light oxidation yields Si cores which are of the order of 5 nm in diameter.

QT Dispersion Measured by Automatic Computerized 12-Lead Electrocardiography Contributes Significantly to Detection of Left Ventricular Hypertrophy in Japanese Patients

This study assessed the diagnostic value of QT dispersion for left ventricular hypertrophy (LVH) as determined by echocardiography. The QT and QRS interval parameters were determined automatically using computerized 12-lead electrocardiography in 153 Japanese outpatients. Corrected QT dispersion (QTcD) and maximal QRS duration (MaxQRS) were significantly correlated with left ventricular mass index. The sum of QTcD and MaxQRS showed the highest correlation with left ventricular mass index among QT and QRS interval parameters and their combinations. The cut-off points for LVH discrimination in this study were different to those reported in Western, mainly Caucasian, populations, suggesting the need for ethnicity-specific LVH detection criteria. A scoring system derived from multiple logistic regression analysis, employing a combination of QTcD, QRS time–voltage product and ST-T change, showed a specificity of 86.3%. It was concluded that QTcD, in addition to QRS time–voltage product and ST-T change, improved the detection of LVH.

Abstract P2-02-01: Characterization of the Breast Lesions by Biexponential Signal Attenuation Analysis of Diffusion-Weighted Magnetic Resonance Images

Purpose: Signal attenuation of diffusion-weighted magnetic resonance images (DWI) in vivo with high b-values is sometimes non-linear when plotted with a semilogarithmic function, but it fits well with the biexponential equation, Sb/S0=f1exp(bD1) + (1-f1)(bD2). Others have indicated that the fast and slow component fractions (f1, 1-f1) of the apparent diffusion coefficients (D1, D2) can be derived by biexponential fitting, and that these fractions correspond to actual diffusion components in the extra-and intracellular space. Here, we investigated the clinical value of DWI for breast screening by performing multi b-factor DWI on healthy volunteers and patients. We then analyzed signals by fitting them with the biexponential equation and compared the fitting parameters of breast lesions.

Patients and methods: This study was approved by our center's institutional review board and all patients and volunteers gave their informed consent. We analyzed data from eight healthy females (controls) and 80 female patients with a total of 100 breast tumors (42 benign and 58 malignant). We performed DWI using 12 and 6 b-values for the controls and patients up to a maximum b-value of 3500 sec/mm2.

Results: We identified the DWI signal attenuation features of the normal mammary gland, and of benign and malignant tumors [Figure1]. The DWI signal attenuation was similar between some proliferative benign tumors and malignancies. A comparison of the parameters derived from biexponential fitting revealed a significant difference in f1 between noninvasive and invasive ductal carcinoma [Figure 2]. Conclusion: The biexponential fitting parameters might reflect the features of tumor cellularity. Thus, to distinguish malignant from benign breast tumors only by DWI is difficult due to the pathological diagnosis that rather emphasizes cell configuration or shape rather than cellularity. Nevertheless, our findings will help to understand why malignant tumors present as high signal intensity in DWI.

MyD88-dependent pathway accelerates the liver damage of Concanavalin A-induced hepatitis

We have explored the pathological role of the MyD88 signaling pathway via Toll-like receptors (TLRs) that mediate the recognition of pathogen-associated molecular patterns (PAMPs) in a murine model of autoimmune hepatitis induced by administering Concanavalin A (ConA). We first found that various TLRs and MyD88 molecules were expressed in liver of Con A-treated and untreated wild-type (WT) mice including liver macrophages. Flowcytometric analysis revealed that liver CD11b(+)CD11c(-) and CD11b(+)CD11c(+) antigen-presenting cells express TLR2, although NK and NKT cells did not. When WT and MyD88(-/-) mice were intravenously administered with Con A, the severity of hepatitis was significantly lower in Con A-injected MyD88(-/-) mice than in WT mice in terms of the histopathology, the levels of serum transaminase and pro-inflammatory cytokines (TNF-alpha, IFN-gamma, and IL-6), and upregulation of CD80/CD86 and TNF-alpha on/in liver macrophages. The results provide evidence of a possible contribution of the TLRs-MyD88 signaling pathway in activating TLR-expressing liver macrophages in the autoimmune hepatitis model, and thus indicate that the strategy of blockade of pathological pathogens via the intestinal lumen may be feasible for the treatment of the disease.

Fcgamma receptors contribute to pyramidal cell death in the mouse hippocampus following local kainic acid injection

Recent studies have demonstrated the contribution of the gamma subunit of the Fc receptor of IgG (FcRgamma) to neuronal death following ischemic injury and Parkinson's disease. We examined the role of FcRgamma in hippocampal pyramidal cell death induced by kainic acid (KA). FcRgamma-deficient mice (FcRgamma-/-) and their FcRgamma+/+ littermates (wild type, B6) received an injection of KA into the dorsal hippocampus. Pyramidal cell death was quantified 24 and 72 h after the injection. The number of survived pyramidal cells was significantly larger in FcRgamma-/- mice than in B6 mice in both the CA1 and CA3. Immunohistochemical and immunofluorescent studies detected FcgammaRIIB protein in parvalbumin neurons, whereas FcgammaRIII and FcgammaRI proteins were detected in microglial cells. No activated microglial cells were detected 24 h after the KA injection in FcRgamma-/- mice, whereas many activated microglial cells were present in B6 mice. The production of nitrotyrosine as well as of the inducible nitric oxide synthase and cyclooxygenase-2 proteins, increased by 16 h after the KA injection in B6 mice. In addition, tissue plasminogen activator and metalloproteinase-2 proteins increased. By contrast, the magnitude of oxidative stress and the increase in protease expression were mild in FcRgamma-/- mice. Co-injection of a neutralizing antibody against FcgammaRll and FcgammaRlll with KA abolished pyramidal cell death and microglial activation. In addition, the neutralizing antibody reduced oxidative stress and expression of proteases. These observations suggested a role for FcgammaRllB in parvalbumin neurons as well as FcRgamma in microglia in pyramidal cell death.

[Thoracoscopic surgery combined with a supraclavicular approach for removing left superior mediastinal neurogenic tumor]

The patient was a 41-year-old female and had been pointed out an abnormal shadow at the left lung apex on the chest X-ray film. Chest computed tomography (CT) scan and magnetic resonance imaging (MRI) revealed a left upper mediastinal mass at the Th1 to Th2 level, measuring 30 mm in size, which was suspected to be a neurogenic tumor. Surgical removal of the tumor using thoracoscopic procedure through 3 chest ports combined with a supraclavicular approach was successfully performed. She was discharged from the hospital on the 7th postoperative day. A pathological examination revealed the tumor to be benign neurilemmoma.

Keyword extraction, ranking, and organization for the neuroinformatics platform

Brain-related researches encompass many fields of studies and usually involve worldwide collaborations. Recognizing the value of these international collaborations for efficient use of resources and improving the quality of brain research, the International Neuroinformatics Coordinating Facility (INCF) started to coordinate the effort of establishing neuroinformatics (NI) centers and portal sites among the different participating countries. These NI centers and portal sites will serve as the conduit for the interchange of information and brain-related resources among different countries. In Japan, several NI platforms under the support of NIJC (NI Japan Center) are being developed with one platform called, Visiome, already operating and publicly accessible at "http://www.platform.visiome.org". Each of these platforms requires their own set of keywords that represent important terms covering their respective fields of study. One important function of this predefined keyword list is to help contributors classify the contents of their contributions and group related resources. It is vital, therefore, that this predefined list should be properly chosen to cover the necessary areas. Currently, the process of identifying these appropriate keywords relies on the availability of human experts which does not scale well considering that different areas are rapidly evolving. This problem prompted us to develop a tool to automatically filter the most likely terms preferred by human experts. We tested the effectiveness of the proposed approach using the abstracts of the Vision Research Journal (VR) and Investigative Ophthalmology and Visual Science Journal (IOVS) as source files.

Excision After Chemoradiotherapy of Invasive Thymoma Extending into the Right Atrium: Report of a Case

We report a case of invasive thymoma with intracardiac extension, resulting from the progression of intracaval growth, in a 56-year-old woman. Initially, the patient received two courses of chemotherapy, but the tumor showed only a modest response; however, subsequent radiotherapy reduced the tumor size further and the intracardiac lesion disappeared, making it possible to excise the tumor without cardiopulmonary bypass. Thus, when a thymoma does not respond well, we recommend radiotherapy as another treatment option, because its effects may allow for less invasive and more complete tumor excision.

Electrical double layer interactions between dissimilar oxide surfaces with charge regulation and Stern–Grahame layers

Models of surfaces with intrinsic ionisable amphoteric surface sites governed by the dissociation of acid-base potential determining ion species together with the capacity for the adsorption of anion and cations of the supporting electrolyte are required to describe both the results of electrokinetic and titration measurements of inorganic oxides. The Gouy-Chapman-Stern-Grahame (CGSG) model is one such model that has been widely used in the literature. The electrical double layer interaction between two dissimilar CGSG surfaces has been studied by Usui recently [S. Usui, J. Colloid Interface Sci. 280 (2004) 113] where erroneous discontinuities in the slope of the pressure-separation relation were observed. We revisit this calculation and provide a simple general methodology to analyse the electrical double layer interaction between dissimilar ionisable surfaces with ion adsorption.

Robustness, evolvability, and optimality of evolutionary neural networks

In a typical optimization problem, the main goal is to search for the appropriate values of the variables that provide the optimal solution of the given function. In artificial neural networks (ANN), this translates to the minimization of the error surface during training such that misclassification is minimized during generalization. However, since optimal training performance does not necessarily imply optimal generalization due to the possibility of overfitting or underfitting, we developed SEPA (Structure Evolution and Parameter Adaptation) which addressed these issues by simultaneously evolving ANN structure and weights. Since SEPA primarily relies on the perturbation function to bring variation in its population, this follow-up study aims to find out SEPAs evolvability, optimality, and robustness in other perturbation functions. Our findings indicate that SEPAs optimal generalization performances are stable and robust from the effect of the different perturbation functions. This is due to the feedback loop between its architecture evolution and weight adaptation such that any shortcoming of the former is compensated by the latter, and vice versa. Our results strongly suggest that proper ANN design requires simultaneous adaptation of ANN structure and weights to avoid one-sided or bias convergence to either the weight or architecture space.

Interaction between dissimilar double layers with like signs under charge regulation on the basis of the Gouy–Chapman–Stern–Grahame model

The force of interaction between two flat double layers with dissimilar surface potentials but of the same signs, in contact with 1-1 electrolyte solutions (0.001, 0.01, and 0.1 M), was calculated as a function of the surface separation. The calculation was carried out on the basis of the Gouy-Chapman-Stern-Grahame double-layer model, incorporating the site-dissociation and site-binding model used previously for many oxide studies. The results demonstrated that the interaction force under surface charge regulation was always repulsive, increasing progressively with decreasing surface separation. This result is in contrast to the predictions of previous theories that are based on the Gouy-Chapman (GC) double-layer model. Dependence of surface potentials and surface charge densities on the surface separation is also presented.

Effects of bezafibrate and pravastatin on remnant-like lipoprotein particles and lipoprotein subclasses in type 2 diabetes

The effects of bezafibrate and pravastatin on remnant-like lipoprotein particles (RLPs) and lipoprotein subclasses were compared in type 2 diabetes. Bezafibrate (400 mg/day) and pravastatin (10 mg/day) were given to 27 Japanese diabetics in a randomized crossover design. RLP cholesterol (RLP-C) and RLP triglyceride (RLP-TG) were measured by an immunoseparation technique. LDL and HDL were separated each into three subclasses (large, medium, small) and their cholesterol (C) contents were measured by an HPLC method. RLP-C was reduced more effectively by pravastatin (bezafibrate -16.0% vs. pravastatin -40.6%, P < 0.05), whereas RLP-TG was reduced more effectively by bezafibrate (-55.2% vs. -35.0%, P < 0.05). Further, pravastatin decreased large and small LDL-C levels equally (large; -23.6%; medium; -17.2%, small; -21.0%), while bezafibrate produced a relatively larger reduction in small LDL-C (-12.1; -16.9; -21.5%). Whereas bezafibrate significantly decreased large HDL-C and increased medium and small HDL-C (-49.6; 34.1; 35.8%), pravastatin significantly increased only medium HDL-C (5.2; 9.4; 5.9%). Bezafibrate reduced RLP-C and RLP-TG more effectively in patients with high TG levels, whereas pravastatin's effect was not markedly influenced by the initial TG level. Thus measurements of RLP-C, RLP-TG, and HPLC subclasses revealed that bezafibrate and pravastatin differently influence the lipoprotein status in type 2 diabetes.

Imidazole-induced cell death, associated with intracellular acidification, caspase-3 activation, DFF-45 cleavage, but not oligonucleosomal DNA fragmentation

Intracellular acidification is known to be involved in the initiation phase of apoptosis. However, the necessity of intracellular acidic conditions in the execution phase of apoptosis remains unknown. In this study, we found that in HL-60 cells imidazole induces cell death, associated with intracellular acidification, caspase-3 activation and DFF-45 cleavage, but not oligonucleosomal DNA fragmentation. A caspase inhibitor prevented cell death but not intracellular acidification. When pHi was neutralized by changing from imidazole-containing medium to fresh medium, oligonucleosomal DNA fragmentation and increased caspase-3 activity was observed in the imidazole-treated HL-60 cells. Furthermore, the DNA fragmentation induced by intracellular neutralization was inhibited by caspase inhibitor treatment. These results indicate that imidazole induces caspase-dependent cell death, and suggest that maintaining pHi in the neutral range is essential for the induction of oligonucleosomal DNA fragmentation in the execution phase of apoptosis.

Zeta Potential of Stearic Acid Monolayer at the Air–Aqueous Solution Interface

The zeta (zeta) potential of an insoluble monolayer of stearic acid at the air-water interface was measured as a function of pH in the presence of 0.0001, 0.001, and 0.01 M NH4NO3. The zeta potential was measured by means of the plane interface technique which involved the determination of the electrophoretic velocity profile of reference (polystyrene latex) particles along the solution depth in a rectangular open quartz cell. The zeta vs pH relationship at 0.001 and 0.01 M NH4NO3 was analyzed in terms of the Gouy-Chapman-Stern-Grahame model for electrical double-layer incorporating a simple site-binding model used previously for many oxide and latex colloid studies. The dissociation constant (pKa) of stearic acid monolayer and double-layer parameters such as integral capacitances of inner and outer Helmholtz layers and the complexation constant of counterion complexes were also estimated.

Antidiabetic effect of an acidic polysaccharide (TAP) from Tremella aurantia and its degradation product (TAP-H)

Continuous oral administration of the acidic polysaccharide (TAP) solution (0.5 g/l) and the TAP-H (degradation products of TAP) solution (1.5 g/l) instead of water for 10 weeks were found to depress plasma glucose increases in diabetes using genetically non-insulin-dependent diabetic model (KK-Ay) mice. TAP and TAP-H significantly lowered levels of insulin, total-cholesterol and triglyceride in the blood of the mice. In excretion to feces, TAP and TAP-H significantly increased the total bile acid, while the cholesterol content of both groups was less than that of the control. Furthermore, TAP and TAP-H significantly decreased the plasma lipoperoxide level. The study shows that TAP and TAP-H have an antidiabetic effect on diabetes model mice.

Upper bound of the expected training error of neural network regression for a Gaussian noise sequence

In neural network regression problems, often referred to as additive noise models, NIC (Network Information Criterion) has been proposed as a general model selection criterion to determine the optimal network size with high generalization performance. Although NIC has been derived using asymptotic expansion, it has been pointed out that this technique cannot be applied under the assumption that a target function is in a family of assumed networks and the family is not minimal for representing the target true function, i.e. the overrealizable case, in which NIC reduces to the well-known AIC (Akaike Information Criterion) and others depending on a loss function. Because NIC is the unbiased estimator of generalization error based on training error, it is required to derive the expectations of errors for neural networks for such cases. This paper gives upper bounds of the expectations of training errors with respect to the distribution of training data, which we call the expected training error, for some types of networks under the squared error loss. In the overrealizable case, because the errors are determined by fitting properties of networks to noise components, including in data, the target set of data is taken to be a Gaussian noise sequence. For radial basis function networks and 3-layered neural networks with bell shaped activation function in the hidden layer, the expected training error is bounded above by sigma2* - 2nsigma2*logT/T, where sigma2* is the variance of noise, n is the number of basis functions or the number of hidden units and T is the number of data. Furthermore, for 3-layered neural networks with sigmoidal activation function in the hidden layer, we obtained the upper bound of sigma2* - O(log T/T) when n > 2. If the number of data is large enough, these bounds of the expected training error are smaller than sigma2* - N(n)sigma2*/T as evaluated in NIC, where N(n) is the number of all network parameters.

Neural readaptation to Earth's gravity following return from space

The consequence of exposure to microgravity on the otolith organs was studied by recording the responses of vestibular nerve afferents supplying the utricular otolith organ to inertial accelerations in four toadfish, Opsanus tau, sequentially for 5 days following two National Aeronautics and Space Administration shuttle orbital flights. Within the first day postflight, the magnitude of response to an applied translation was on average three times greater than for controls. The reduced gravitational acceleration in orbit apparently resulted in an upregulation of the sensitivity of utricular afferents. By 30 h postflight, responses were statistically similar to control. The time course of return to normal afferent sensitivity parallels the reported decrease in vestibular disorientation in astronauts following return from space.

Successful catheter intervention for acute coronary syndrome in a patient with antiphospholipid syndrome

Antiphospholipid syndrome (APS) has the clinical manifestations of systemic vascular thrombotic disorders. Although coronary events are infrequent, they have been described. Early coronary interventions and vein graft bypass frequently failed because of thrombosis. Here we present a case of successful coronary intervention and management of acute coronary syndrome under a strictly controlled coagulation state in an APS patient.

Zeta Potential of Insoluble Monolayer of Long-Chain Alcohol at the Air-Aqueous Solution Interface

The zeta potential of a close-packed insoluble monolayer of 1-hexacosanol at the air-water interface in the presence of 0.001 M NH(4)NO(3) was measured as a function of pH by means of the plane interface technique. The negative zeta potential increased with the increase of pH up to about 9. The negative charge at the monolayer-water interface is considered to be due to the dissociation of protons from hydrated alcohol water clusters at the surface. The zeta potential results were analyzed in terms of the site dissociation and site-binding mechanism within the Gouy-Chapman-Stern-Grahame double-layer model of the metal oxide-water interface. Copyright 2001 Academic Press.

The carboxyl terminal sequence of nucleolar protein B23.1 is important in its DNA polymerase alpha-stimulatory activity

The protein B23 is a major nucleolar phosphoprotein comprising two isoforms, B23.1 and B23.2, which differ only in their carboxyl-terminal short sequences, the N-terminal 255 residues being identical in both forms. Both B23.1 and B23.2 stimulated immunoaffinity-purified calf thymus DNA polymerase alpha in a dose-dependent manner. The stimulatory effect of protein B23.1, the longer isoform, was found to be 2-fold greater than that of B23.2. Purified DNA polymerase alpha bound tightly to a protein B23.1-immobilized column, while it bound weakly to a protein B23.2-immobilized column. Surface plasmon resonance studies by BIAcore further showed that protein B23.1 bound to the DNA polymerase alpha-(dA).(dT) complex more tightly than did protein B23.2. The protein B23 isoforms appear to interact directly with the DNA polymerase alpha protein and not through the bound nucleic acid. These observations indicated that protein B23 physically bound to the DNA polymerase alpha and stimulated the enzyme activity. Product analyses showed that protein B23 greatly enhanced the reaction both in amount and length of product DNA, whereas it did not significantly alter the processivity of polymerization. In contrast, protein B23 effectively protected DNA polymerase alpha from heat inactivation. These results suggest that protein B23 stabilizes DNA polymerase alpha that is detached from product DNA, allowing the enzyme to be recruited for further elongation. Moreover, experiments using various C-terminal deletion mutants of protein B23 indicated that 12 amino acids at the C-terminal end of B23.1, which are absent in B23.2, may be essential for the full stimulation of the DNA polymerase alpha.