Change in carrier type in high-k gate carbon nanotube field-effect transistors by interface fixed charges

We study the phenomenon of change in carrier type in carbon nanotube field-effect transistors (CNFETs) caused by the atomic layer deposition (ALD) of a HfO(2) gate insulator. When a HfO(2) layer is deposited on a CNFET, the type of carrier changes from p-type to n-type. The so-obtained n-type device has good performance and stability in air. The conductivity of such a device with a channel length of 0.7 microm is 11% of the quantum conductance 4e(2)/h. The contact resistance for electron current is estimated to be 14 kOmega. The n-type conduction of this CNFET is maintained for more than 100 days. The change in carrier type is attributed to positive fixed charges introduced at the interface between the HfO(2) and SiO(2) layers. We also propose a novel technique to control the type of conduction by utilizing interface fixed charges; this technique is compatible with Si CMOS process technology.

Plasma hormone levels and semen quality in male cats during non-breeding and breeding seasons

Female cats are known to be seasonal breeders and male cats annual breeders. Despite this, there are limited data on the influence of breeding season (BS) on hormone concentration and semen quality in the male cat. This study compared plasma concentrations of LH and testosterone (T), and semen quality during the non-breeding season (NBS) and BS in five male cats subject to natural hours of daylight but a constant environmental temperature. Plasma LH and T concentrations were higher during the BS in 2/35 and 3/5 cats, respectively, although when comparing both hormones combined, values were higher during the BS than the NBS in all cats (p < 0.01). There were no significant differences in the percentage of abnormal sperm between the cats. Overall, semen quality was superior during the BS with larger semen volume in 2/5, sperm motility in 2/5 and sperm viability in 3/5 cats. Although there was a clear seasonal effect on hormone secretion and semen quality, during the NBS all cats were likely to have been fertile.

Persistent gut motor dysfunction in a murine model of T-cell-induced enteropathy

BACKGROUND

Inflammatory bowel disease (IBD) patients in remission often experience irritable bowel syndrome (IBS)-like symptoms. We investigated the mechanism for intestinal muscle hypercontractility seen in T-cell-induced enteropathy in recovery phase.

METHODS

BALB/c mice were treated with an anti-CD3 antibody (100 microg per mouse) and euthanized at varying days post-treatment to investigate the histological changes, longitudinal smooth muscle cell contraction, cytokines (Th1, Th2 cytokines, TNF-alpha) and serotonin (5-HT)-expressing enterochromaffin cell numbers in the small intestine. The role of 5-HT in anti-CD3 antibody-induced intestinal muscle function in recovery phase was assessed by inhibiting 5-HT synthesis using 4-chloro-DL-phenylalanine (PCPA).

KEY RESULTS

Small intestinal tissue damage was observed from 24 h after the anti-CD3 antibody injection, but had resolved by day 5. Carbachol-induced smooth muscle cell contractility was significantly increased from 4 h after injection, and this muscle hypercontractility was evident in recovery phase (at day 7). Th2 cytokines (IL-4, IL-13) were significantly increased from 4 h to day 7. 5-HT-expressing cells in the intestine were increased from day 1 to day 7. The 5-HT synthesis inhibitor PCPA decreased the anti-CD3 antibody-induced muscle hypercontractility in recovery phase.

CONCLUSIONS & INFERENCES

Intestinal muscle hypercontractility in remission is maintained at the smooth muscle cell level. Th2 cytokines and 5-HT in the small intestine contribute to the maintenance of the altered muscle function in recovery phase.

Impact of double-balloon endoscopy on the diagnosis of jejunoileal involvement in primary intestinal follicular lymphomas: a case series

In recent years, primary gastrointestinal follicular lymphoma has been increasingly detected in the duodenum on esophagogastroduodenoscopy (EGD). Primary gastrointestinal follicular lymphomas are frequently distributed to multiple sites in the gastrointestinal tract. Therefore, investigation into the spread of follicular lymphomas in the small bowel is important in order to determine the most appropriate treatment strategy. The performance of double-balloon endoscopy (DBE) in the diagnosis of jejunoileal follicular lymphoma lesions has not been fully evaluated. We aimed to investigate the value of DBE in addition to computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) in the diagnosis of jejunoileal follicular lymphoma. DBE with biopsy was performed in seven patients with primary duodenal follicular lymphoma diagnosed by EGD, in order to investigate jejunoileal involvement. Jejunoileal follicular lymphoma lesions were detected by DBE in six out of the seven patients (three in the jejunum and three in the jejunum and ileum), whereas CT and (18)F-FDG-PET failed to detect the existence of these lesions. Endoscopic findings of the jejunoileal lesions revealed multiple white nodules and white villi, which were similar to those of duodenal lesions. DBE was more useful for the diagnosis of jejunoileal involvement in primary intestinal follicular lymphoma than CT and (18)F-FDG-PET. The use of DBE will become important for determining the most appropriate treatment for gastrointestinal follicular lymphoma.

Vascular endothelial growth factor in monochorionic twins with twin-twin transfusion syndrome

OBJECTIVE

The purpose of this study was to determine vascular endothelial growth factor (VEGF) concentrations in the donor and the recipient in monochorionic twin pregnancies with twin-twin transfusion syndrome (TTTS) and single pregnancies in order to investigate the involvement of VEGF in the pathophysiology of TTTS.

METHODS

Six twin pregnancies in 11 monochorionic twin pregnancies complicated with TTTS and 11 single control pregnancies were compared. Gestational age-matched fetal blood and placental samples were obtained at birth. Serum VEGF concentration in the umbilical vein was measured by an enzyme-linked immunoabsorbant assay. Tissue protein expression of VEGF was determined by using immunohistochemistry. Western blot analysis and scanning densitometry were used to quantify and compare the VEGF expression in the terminal villi.

RESULTS

Serum VEGF concentrations in the umbilical vein in both donors and recipients tended to be higher than those in the controls. Immunolocalization of VEGF in terminal villous placenta samples in both donors and recipients was mainly observed in the syncytiotrophoblastic layer and vascular endothelial cells with less intense staining in stromal cells. The expression of VEGF in the donor placenta increased significantly (p=0.006) compared to that in the control placenta, but the expression of VEGF in the recipients tended to be higher than in the controls.

CONCLUSION

Intrauterine circulatory imbalance may induce changes in VEGF expression and these alterations may be involved in both donor and recipient in the pathogenesis of TTTS, due to the maintenance of hemodynamic stability between the circulation of the twins.

Constructing and testing the thermodynamic limits of synthetic NAD(P)H:H2 pathways

NAD(P)H:H₂ pathways are theoretically predicted to reach equilibrium at very low partial headspace H₂ pressure. An evaluation of the directionality of such near‐equilibrium pathways in vivo, using a defined experimental system, is therefore important in order to determine its potential for application. Many anaerobic microorganisms have evolved NAD(P)H:H₂ pathways; however, they are either not genetically tractable, and/or contain multiple H₂ synthesis/consumption pathways linked with other more thermodynamically favourable substrates, such as pyruvate. We therefore constructed a synthetic ferredoxin‐dependent NAD(P)H:H₂ pathway model system in Escherichia coli BL21(DE3) and experimentally evaluated the thermodynamic limitations of nucleotide pyridine‐dependent H₂ synthesis under closed batch conditions. NADPH‐dependent H₂ accumulation was observed with a maximum partial H₂ pressure equivalent to a biochemically effective intracellular NADPH/NADP⁺ ratio of 13:1. The molar yield of the NADPH:H₂ pathway was restricted by thermodynamic limitations as it was strongly dependent on the headspace : liquid ratio of the culture vessels. When the substrate specificity was extended to NADH, only the reverse pathway directionality, H₂ consumption, was observed above a partial H₂ pressure of 40 Pa. Substitution of NADH with NADPH or other intermediates, as the main electron acceptor/donor of glucose catabolism and precursor of H₂, is more likely to be applicable for H₂ production.

Spinal anterior horn cells in sporadic amyotrophic lateral sclerosis show ribosomal detachment from, and cisternal distention of the rough endoplasmic reticulum

AIMS

Sporadic amyotrophic lateral sclerosis (ALS) is a progressive and invariably fatal disease involving the upper and lower motor neurones of adult humans. Among the neuropathological features of the disease, abnormalities in the protein-synthesizing system in motor neurones of the brainstem and spinal cord, such as a decrease of cytoplasmic RNA and rough endoplasmic reticulum (rER) (chromatolysis), defective editing of the Q/R site of the glutamate receptor subunit GluR2 mRNA, fragmentation of the Golgi apparatus and accumulation of ubiquitinated inclusions and abnormal TdP-43 protein have been reported to be essential for the degeneration. In relation to these features, although the possibility of ER stress has been reported in motor neurones of the brainstem and spinal cord of ALS patients, the rER itself has not been a main target of ultrastructural investigation.

METHODS

The present study examined the rER, ultrastructurally and quantitatively in the spinal anterior horn cells (AHCs) of 21 Japanese patients with sporadic ALS and eight Japanese control subjects.

RESULTS AND CONCLUSIONS

It was found that: (i) the rER cisternae in AHCs showing central chromatolysis were fragmented, but retained their width and had normally attached ribosomes, and (ii) the rER cisternae in shrunken AHCs were irregularly distended with detachment of the ribosomes, thus suggesting that (iii) ribosomal detachment was related to rER distention.

Symmetric temporal abnormalities on MR imaging in amyotrophic lateral sclerosis with dementia

BACKGROUND AND PURPOSE

Our aim was to clarify imaging findings of amyotrophic lateral sclerosis with dementia (ALSD).

MATERIALS AND METHODS

T2-weighted MR images (T2WI) of 3 patients with ALSD (2 men, 1 woman; 58-71 years of age) and 21 patients with ALS without dementia (12 men, 9 women; 46-74 years of age) were examined for frontotemporal lobar atrophy and signal-intensity alterations in the white matter of the anterior temporal lobes, corticospinal tracts (CST), and precentral gyri and in precentral cortices. The brain of one of the patients with ALSD was examined at autopsy.

RESULTS

All patients with ALSD showed bilateral frontotemporal atrophy mostly with temporal lobe dominance. In the ALSD group, T2WI demonstrated hyperintensity in the subcortical white matter on the medial side of the anterior temporal lobes, whereas in the group without dementia, none showed this imaging finding. MR images demonstrated no abnormal signal-intensity changes in CST in the internal capsule or the brain stem in the ALSD group. In the group without dementia, 6 patients (28.6%) showed this imaging finding. In neuropathologic examinations of the brain of 1 patient with ALSD, myelin-stained sections of the brain demonstrated loss of myelin in the subcortical white matter on the medial side of the anterior temporal white matter.

CONCLUSIONS

A symmetric pattern of frontotemporal atrophy and anteromedial subcortical hyperintensities in the temporal lobes on T2WI could be characteristic of ALSD.

Effects of cilostazol on cerebral blood flow, P300, and serum lipid levels in the chronic stage of cerebral infarction

The effects of cilostazol (Pletaal, Otsuka Pharmaceutical Co., Tokyo, Japan) on cerebral blood flow, P300 event-related potentials, and serum lipid levels were examined in patients in the chronic stage of cerebral infarction. This study included 20 patients (13 men and 7 women, mean age 67 +/- 11 years) with cerebral infarction who had taken ticlopidine (100 mg orally, twice a day). Quantitative cerebral blood flow measurements by Patlak plot analysis, ultrasound examinations of the common carotid arteries, and measurements of P300 event-related potentials and serum lipid levels were performed. Ticlopidine was then replaced with cilostazol (100 mg orally, twice a day) while other medications remained unchanged. The same examinations were performed again 3 months later. After replacement of ticlopidine with cilostazol, cerebral blood flow significantly increased in the frontal white matter, temporal cortex, and occipital cortex compared with cerebral blood flow before replacement with cilostazol. Ultrasonograms of the common carotid arteries showed no significant differences in intima-media thickness before and after replacement. However, peak systolic velocity, time-averaged peak velocity, and volume flow all significantly increased after replacement. Blood flow in the frontal white matter showed a significant negative correlation with P300 latency before and after replacement of ticlopidine with cilostazol. And P300 latency improved significantly after replacement with cilostazol. Regarding lipid levels, total cholesterol, triglycerides, and remnant-like particles-cholesterol all decreased significantly after replacement with cilostazol. Cilostazol, an inhibitor of platelet aggregation, was thus concluded to be effective in improving cerebral blood flow, cerebral function, and serum lipid levels in patients in the chronic stage of cerebral infarction.

Glyceraldehyde-3-phosphate ferredoxin oxidoreductase from Methanococcus maripaludis

The genome sequence of the non-sugar-assimilating mesophile Methanococcus maripaludis contains three genes encoding enzymes: a nonphosphorylating NADP(+)-dependent glyceraldehyde-3-phosphate dehydrogenase (GAPN), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and glyceraldehyde-3-phosphate ferredoxin oxidoreductase (GAPOR); all these enzymes are potentially capable of catalyzing glyceraldehyde-3-phosphate (G3P) metabolism. GAPOR, whose homologs have been found mainly in archaea, catalyzes the reduction of ferredoxin coupled with oxidation of G3P. GAPOR has previously been isolated and characterized only from a sugar-assimilating hyperthermophile, Pyrococcus furiosus (GAPOR(Pf)), and contains the rare metal tungsten as an irreplaceable cofactor. Active recombinant M. maripaludis GAPOR (GAPOR(Mm)) was purified from Escherichia coli grown in minimal medium containing 100 muM sodium molybdate. In contrast, GAPOR(Mm) obtained from cells grown in medium containing tungsten (W) and W and molybdenum (Mo) or in medium without added W and Mo did not display any activity. Activity and transcript analysis of putative G3P-metabolizing enzymes and corresponding genes were performed with M. maripaludis cultured under autotrophic conditions in chemically defined medium. The activity of GAPOR(Mm) was constitutive throughout the culture period and exceeded that of GAPDH at all time points. As GAPDH activity was detected in only the gluconeogenic direction and GAPN activity was completely absent, only GAPOR(Mm) catalyzes oxidation of G3P in M. maripaludis. Recombinant GAPOR(Mm) is posttranscriptionally regulated as it exhibits pronounced and irreversible substrate inhibition and is completely inhibited by 1 muM ATP. With support from flux balance analysis, it is concluded that the major physiological role of GAPOR(Mm) in M. maripaludis most likely involves only nonoptimal growth conditions.

Phase II study of ifosfamide, carboplatin and etoposide (ICE) in recurrent glioblastoma

2066

Background: To evaluate the efficacy and tolerability of ifosfamide, carboplatin and etoposide ( ICE ) in patients with recurrent glioblastoma. Methods: This was an open-label, single-center phase II trial. Forty-two patients with first recurrent glioblastoma after surgery, standard radiotherapy and a first-line temozolomide-based or ACNU-based chemotherapy, were enrolled.The primary endpoint was progression-free survival at 6 months ( PFS-6 ), and secondary endpoints were response rate, toxicity, and survival. Chemotherapy consisted of Ifosfamide ( 700 mg / m2 on day 1, 2 and 3 ), carbopaltin ( 100 mg / m2 on day 1 ), etoposide ( 70 mg / m2 on day 1, 2, and 3 ), every 6 weeks. Results: PFS-6 was 37 %. The median PFS was 17 weeks. Response rate was 27 %. Adverse events were generally mild ( grade 1 or 2 ) and consisted mainly of alopecia. Conclusions: This regimen is well tolerated and has activity in patients with recurrent glioblastoma.

No significant financial relationships to disclose.

Signal transduction in SARS-CoV-infected cells

abstract: Severe acute respiratory syndrome (SARS) is a newly found infectious disease that is caused by a novel human coronavirus, SARS coronavirus (SARS‐CoV). Because the mortality rate of SARS patients is very high, understanding the pathological mechanisms of SARS not only in vivo but in vitro is important for the prevention of SARS. Activation of signaling pathways caused by SARS‐CoV infection leads to the phosphorylation and activation of downstream molecules. Two conflicting cellular programs, apoptosis to eliminate virus‐infected cells and survival to delay apoptosis by producing antiviral cytokines, occur in SARS patients. Recent studies regarding SARS and SARS‐CoV have clarified that activation of mitogen‐activated protein kinases (MAPKs) plays important roles in upregulation of cytokine expression and apoptosis both in vitro and in vivo. Both Akt and p38 MAPK are keys for determination of cell survival or death in SARS‐CoV‐infected cells in vitro. Agents being developed to target these signaling cascades may be important for the design of anti‐SARS‐CoV drugs. This review highlights recent progress regarding SARS‐CoV biology, especially signal transduction in SARS‐CoV‐infected cells.