High-speed organic single-crystal transistors gated with short-channel air gaps: Efficient hole and electron injection in organic semiconductor crystals

Short-channel, high-mobility organic filed-effect transistors (OFETs) are developed based on single crystals gated with short-channel air gaps. The high hole mobility of 10 cm²/Vs for rubrene, and high electron mobility of 4 cm²/Vs for PDIF-CN₂ crystals are demonstrated even with a short channel length of 6 μm. Such performance is due to low contact resistance in these devices estimated to be as low as ～0.5 kΩ cm at gate voltage of ?4 V for rubrene. With the benefit of the short channel length of 4.5 μm in a new device architecture with less parasitic capacitance, the cutoff frequency of the rubrene air–gap device was estimated to be as high as 25 MHz for drain voltage of ?15 V, which is the fastest reported for p-type OFETs, operating in ambient conditions.     

SYNTHESES AND PHOTOPHYSICAL PROPERTIES OF FULLEROPYRROLIDINES CONTAINING PHOTOACTIVE UNITS

As a reply to the title question, it has been elucidated that metallic bucky tubes are equivalent to those involving plural numbers of isolated polyacetylene (PA) skeletons (cis-type) arranged either in a helical or non-helical manner on the tube surface. Such helical PA skeletons guarantee the metallic conduction path to the electrons near the Fermi level (spiralons). Control of the flow of these spiralons may open up a stage for nano-technology of the electronic devices such as molecular solenoid applicable to molecular electromagnet, molecular electric generator and so on.     

Cloning, structural analysis and expression of the gene encoding aspartate aminotransferase from the thermophilic cyanobacterium Phormidium lapideum

The aspartate aminotransferase gene from the thermophilic cyanobacterium Phormidium lapideum was cloned and expressed in Escherichia coli. The ORF of 1167 nucleotides encodes a protein of 388 amino acids having a molecular weight of 42,099. A molecular model of PIAspAT shows structural features similar to those of the Thermus thermophilus AspAT.     

Identification of tumor vascular antigens by monoclonal antibodies prepared from rat-tumor-derived endothelial cells

An industrial erythromycin production strain of Saccharopolyspora erythraea spp. was used to demonstrate that careful genetic engineering can significantly improve productivity. The chromosomally integrated Vitreoscilla hemoglobin gene (vhb) was shown to enhance the final titer of erythromycin by some 70% compared to the original S. erythraea spp. Overall, specific erythromycin yields were about 2.5 g of erythromycin/g of total protein for S. erythraea::vhb but <1 for the S. erythraea spp. The maximum rates of biosynthesis were 57.5 mg of erythromycin/(L/h) and 24.3 mg/(L/h) for the recombinant strain S. erythraea::vhb and S. erythraea spp., respectively. Overall space-time yield was 100% higher for the S. erythraea::vhb fermentation (1.1 g of erythromycin/(L/day)) than for the S. erythraea spp. fermentation (0. 56 g of erythromycin/(L/day)). The genetic stability of the recombinant strain was high, and no selective pressure was needed throughout the cultivations. Expression of functional Vitreoscilla hemoglobin throughout the cultivations was verified by CO difference spectrum assays.     

Ataxia-telangiectasia in the Japanese population: identification of R1917X, W2491R, R2909G, IVS33+2T-->A, and 7883del5, the latter two being relatively common mutations

Postmenopausal uterine bleeding is an indication to sample the endometrium for diagnostic purposes. The endometrial brush cytologies of 20 advanced postmenopausal women collected at the time of hysterectomy in order to benchmark the expected morphology of postmenopausal endometrial brushings were reviewed. No women had symptoms or gross findings of primary endomyometrial disease. Endometrium was collected at the surgical pathology laboratory using the Tao Brush and CytoRich Fixative System. After formalin fixation of the uterus, the entire endometrium was embedded for routine histology. Sixteen endometrial brushings and matched endometrial sections showed endometrial atrophy, one brushing showed many ciliated epithelial cells, and three brushings showed focal (less than 10%) epithelial-cell atypia. In two atypias, abnormal endometrial epithelial-cell sheets contained enlarged, clear nuclei with nuclear notches and grooves resembling papillary thyroid cancer. One case showed no histological counterpart to this finding. The other case showed thickening of the pericornual fundic endometrium with cystic glands. The third case with epithelial atypia showed abnormal endometrial-cell sheets with nuclei resembling atypical hyperplasia or type I endometrial adenocarcinoma; corresponding endometrial tissue sections showed rare, irregular glands and back-to-back gland clusters with equivalent nuclear features. Atypical epithelium may be found in atrophic uteri in the absence of gross endometrial thickening. This may be a common event related either to de novo intraepithelial dysplasia in a noncycling endometrium or to hyperplasia that has partly regressed with estradiol withdrawal. This study shows that, in addition to endometrial intraepithelial carcinoma (EIC), isolated atypical glands with morphological and immunohistochemical features of atypical hyperplasia or type I endometrial adenocarcinoma may be found in grossly normal advanced postmenopausal endometrium of asymptomatic patients. This atypical epithelium is readily apparent in endometrial brush preparations, but requires serial sectioning of the endometrium to be demonstrated histologically. We have not established the natural history of this lesion, and in the absence of EIC or gross endometrial thickening indicative of atypical hyperplasia, we do not know whether this degree of epithelial atypia should be an indication for hysterectomy.     

Cytoplasmic gene expression system enhances the efficiency of cationic liposome-mediated in vivo gene transfer into mouse brain

The use of in vivo electroporation in combination with a chemotherapeutic agent (electrochemotherapy) for the treatment of liver tumors was examined. Induced rat hepatomas were treated with a 0.5 unit intratumor bleomycin dose followed by rectangular direct current pulses. Six pulses were administered during treatment using a needle array electrode that rotated the applied electric field around the tumors. A 84.6% objective response rate resulted for tumors that received both bleomycin and electric pulses. Control groups that received partial or no treatment showed less than 10% objective response rates. These results indicate that electrochemotherapy can be translated from the treatment of cutaneous cancers to the treatment of liver tumors and other internal tumors.     

Anti‐inflammatory effects of linagliptin in hemodialysis patients with diabetes

Inflammation and glycemic control are important prognosis‐related factors for hemodialysis (HD) patients; moreover, inflammation affects insulin secretion. Here, we evaluated the anti‐inflammatory effects of monotherapy with linagliptin—a dipeptidase‐4 inhibitor—in HD patients with type 2 diabetes. We examined 21 diabetic HD patients who were not receiving oral diabetes drugs or insulin therapy and with poor glycemic control (glycated albumin [GA] level, >20%). Linagliptin (5 mg) was administered to the patients daily. The levels of prostaglandin E2 (PGE2), interleukin‐6 (IL‐6), high‐sensitivity C‐reactive protein, GA, blood glucose, and active glucagon‐like peptide‐1 were determined before and 6 months after treatment. Body weight and serum levels of albumin, hemoglobin, total cholesterol, and low‐density lipoprotein cholesterol were also recorded before and after treatment. The levels of PGE2 and GA were significantly decreased 1 month after starting linagliptin therapy, whereas the IL‐6 levels were significantly decreased 6 months after starting linagliptin therapy. After 6 months of treatment, the PGE2 levels decreased from 188 ± 50 ng/mL to 26 ± 5 ng/mL; IL‐6 levels, from 1.5 ± 0.4 pg/mL to 0.6 ± 0.1 pg/mL; and GA levels, from 21.3% ± 0.6% to 18.0% ± 0.6%. Glucagon‐like peptide‐1 levels increased 2.5‐fold during the treatment. Over the 6‐month treatment period, body weight and levels of high‐sensitivity C‐reactive protein, blood glucose, albumin, hemoglobin, and cholesterol did not change; none of the patients exhibited hypoglycemia. The anti‐inflammatory effects of linagliptin monotherapy indicate that it may serve as a useful glucose control strategy for HD patients with diabetes.     

Metal-lon stimulation and inhibition of lysophospholipase D which generates bioactive lysophosphatidic acid in rat plasma

We found that lysophospholipase D (LPLD) in rat plasma prefers unsaturated to saturated lysophosphatidylcholines as substrates, generating a biologically active lipid, lysophosphatidic acid, but it does not hydrolyze diacyl-phospholipids. In this study, this LPLD required a metal ion for activity, Co²⁺ being the most effective, followed in order by Zn²⁺, Mn²⁺, and Ni²⁺. This metal-ion-stimulated LPLD with unique substrate specificity, which has not been described previously, was susceptible to thiol-blocking reagents and serine esterase inhibitors, but not to a histidine-modifying reagent. Consistent with results using thiol-modifying agents, short-chain fatty aldehydes, secondary products of lipid peroxidation, were found to inhibit LPLD. Addition of dibutylhydroxytoluene or butylhydroxyanisole to the plasma increased the activity of this enzyme, probably in a manner independent of its antioxidant activity, since another antioxidant, propyl gallate, was rather inhibitory. These results suggest that rat plasma contains an active LPLD that differs in some properties from other members of the known phospholipase D family detected in animal tissues and body fluids.     

Synergistic immunosuppression caused by high-dose methylprednisolone and cardiopulmonary bypass

BACKGROUND: Steroid use during cardiac operations may reduce the risk of postperfusion lung syndrome, but both cardiopulmonary bypass and steroids are immunosuppressive. The synergistic effects of the bypass and steroids on patients' immunologic activities, hemodynamics, and metabolisms during and after heart operations have not been clarified systematically. METHODS: Twenty-four patients undergoing valve replacement were studied in a randomized, double-blind trial. Twelve of these patients (S group) received bolus methylprednisolone, 20 mg/kg body weight, and the remaining 12 patients (C group) received a placebo intravenously before and after bypass. Blood cell count, C-reactive protein, lymphocyte surface markers (CD3, CD4, CD8, CD16, and CD20), phytohemagglutinin response, interleukin-2 production, and natural killer cell activity were examined on admission through day 7. Cardiac output, blood gas, electrolyte, lactate, and serum glucose levels were examined perioperatively. RESULTS: The peak white blood cell count in the S group was higher than that in the C group (analysis of variance: p [group] = 0.0436). The peak C-reactive protein level was higher in the C group than in the S group (p [group] < 0.0001). From the analysis of the surface markers, the steroid increased the natural killer cells before and soon after bypass (p [group] = 0.0117), and later tended to increase the CD4+ T and B cells during the postoperative recovery period. The phytohemagglutinin response in both groups decreased after bypass (p [time] < 0.0001), but the steroid caused exaggerated decreases before (p < 0.01 by Student's t test) and soon after (p < 0.001) bypass in the S group (analysis of variance: p [group] = 0.0127). The interleukin-2 production was suppressed by bypass alone after the bypass in the C group, but was further suppressed by the steroid before and after bypass in the S group (p [group] = 0.0446). The cardiac index, water balance, electrolytes, arterial oxygen tension, and timing of extubation were not different between the groups. In contrast, the glucose (p [group] = 0.0486) and lactate (p [group] = 0.0525) levels were higher in the S group than those in the C group. CONCLUSIONS: T-cell functions are synergistically suppressed by cardiopulmonary bypass and high-dose methylprednisolone in heart operations. The hemodynamic benefits of the steroid are negligible, whereas glucose tolerance is worsened by the steroid during bypass.