TRP Channels as Sensors and Signal Integrators of Redox Status Changes

Proteins are capable of sensing the redox status of cells. Cysteine residues, which react with oxidants, reductants, and electrophiles, have been increasingly recognized as the mediators of this redox sensitivity. Cation channels encoded by the transient receptor potential (trp) gene superfamily are characterized by a wide variety of activation triggers that act from outside and inside the cell. Recent studies have revealed that a class of TRP channels is sensitive to changes in redox status and is notably susceptible to modifications of cysteine residues, such as oxidation, electrophilic reaction, and S-nitrosylation of sulfhydryls. In this review, we focus on TRP channels, which directly sense redox status, and discuss the biological significance of cysteine modifications and the consequences of this chemical reaction for physiological responses

Neuronal apoptosis and inflammatory responses in the central nervous system of a rabbit treated with Shiga toxin-2

<p>Abstract</p> <p>Background</p> <p>Shiga toxins (Stxs) are the major agents responsible for hemorrhagic colitis and hemolytic-uremic syndrome (HUS) during infections caused by Stx-producing <it>Escherichia coli </it>(STEC) such as serotype O157:H7. Central nervous system (CNS) involvement is an important determinant of mortality in diarrhea associated-HUS. It has been suggested that vascular endothelial injuries caused by Stxs play a crucial role in the development of the disease. The current study investigates the relationship between the cytotoxic effects of Stxs and inflammatory responses in a rabbit brain treated with Stx2.</p> <p>Methods</p> <p>In a rabbit model treated with purified Stx2 or PBS(-), we examined the expression of the Stx receptor globotriaosylceramide (Gb3)/CD77 in the CNS and microglial activation using immunohistochemistry. The relationship between inflammatory responses and neuronal cell death was analyzed by the following methods: real time quantitative reverse transcriptase (RT)-polymerase chain reaction (PCR) to determine the expression levels of pro-inflammatory cytokines, and the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) method to detect apoptotic changes.</p> <p>Results</p> <p>Gb3/CD77 expression was detected in endothelial cells but not in neurons or glial cells. In the spinal cord gray matter, significant levels of Gb3/CD77 expression were observed. Severe endothelial injury and microvascular thrombosis resulted in extensive necrotic infarction, which led to acute neuronal damage. Conversely, in the brain, Stx receptor expression was much lower. The observed neuropathology was less severe. However, neuronal apoptosis was observed at the onset of neurological symptoms, and the number of apoptotic cells significantly increased in the brain at a later stage, several days after onset. Microglial activation was observed, and tumor necrosis factor (TNF)-α and interleukin (IL)-1β mRNA in the CNS parenchyma was significantly up-regulated. There was significant overexpression of TNF-α transcripts in the brain.</p> <p>Conclusion</p> <p>This study indicates that Stx2 may not directly damage neural cells, but rather inflammatory responses occur in the brain parenchyma in response to primary injury by Stx2 in vascular endothelial cells expressing Gb3/CD77. These findings suggest that neuroinflammation may play a critical role in neurodegenerative processes during STEC infection and that anti-inflammatory intervention may have therapeutic potential.</p

Adsorption of benzene derivatives on allophane

The adsorption properties of benzene derivatives from water on allophane, extracted from soil, have been investigated by UV and FTIR spectroscopic measurements. Allophane adsorbs benzoic acid, phthalic acid, benzaldehyde, ethyl benzoate, and diethyl phthalate. Benzoic acid, phthalic acid, and benzaldehyde formed carboxylate anions on the positive sites of the hydrated alumina surface of allophane. In the case of adsorption from an acidic solution (pH 2), a small amount of a neutral species of benzoic acid was detected on the allophane. Ethyl benzoate and diethyl phthalate were adsorbed by an interaction between their carbonyl groups and the hydroxyl groups of the allophane. It was confirmed that allophane has an adsorption ability for the benzene derivatives that are not only ionic but also polar molecules. Allophane was found to be available as an absorbent for use in water purification by a simple procedure.ArticleAPPLIED CLAY SCIENCE. 43(2):160-163 (2009)journal articl

IPC2010-31433 PIPE BENDING TEST WITH GIRTH WELDING ON X80 GRADE SAW PIPES

ABSTRACT This study was planned as a part of a test program to confirm the effect of girth welds on the strain capacity of pipes. In this study, full-scale pipe bending tests are performed by using X80 SAW pipe. This paper covers pipe manufacturing procedure, developed welding procedure to obtain even match weld metal and properties of welded joints. And this work demonstrated that the X80 pipes welded under the developed procedure fractured in base metal remote from girth welded portion by full scale pipe bending test conducted under the internal pressure of 72 % SMYS of X80. INTRODUCTION Oil and gas exploration from extreme region such as remote areas, arctic areas and so on will increase due to extensive needs for oil and gas resources. High strength steel pipe (X80 and over) for gas transmission pipelines has been developed to reduce the gas transportation by high-pressure operation. To maximize economic advantages, the use of high strength steels in pipeline systems has been investigated. X80, X100 and X120 grade steels have been developed and utilized for gas pipeline

Intra-Abdominal Bleeding during Pregnancy, Preterm Delivery, and Placental Polyp in a Long-Term Survivor of Neuroblastoma: A Case Report

Background. There are few reports of pregnancies in long-term survivors of pelvic neuroblastoma. Case. A 30-year-old Japanese woman with a history of pelvic neuroblastoma in her childhood, which was treated with surgical resection, chemotherapy, and radiation. Her pregnancy continued with conservative management, but she delivered a 510 g female infant at 23 weeks of gestation due to sudden onset of labor pain. She also had a placental polyp and developed massive postpartum bleeding. Conclusion. Cancer treatment, especially radiation therapy, in childhood may cause adverse outcomes during pregnancy in long-term survivors of neuroblastoma