A perpendicular-anisotropy CoFeB-MgO magnetic tunnel junction

Magnetic tunnel junctions (MTJs) with ferromagnetic electrodes possessing a perpendicular magnetic easy axis are of great interest as they have a potential for realizing next-generation high-density non-volatile memory and logic chips with high thermal stability and low critical current for current-induced magnetization switching. To attain perpendicular anisotropy, a number of material systems have been explored as electrodes, which include rare-earth/transition-metal alloys, L1(0)-ordered (Co, Fe)-Pt alloys and Co/(Pd, Pt) multilayers. However, none of them so far satisfy high thermal stability at reduced dimension, low-current current-induced magnetization switching and high tunnel magnetoresistance ratio all at the same time. Here, we use interfacial perpendicular anisotropy between the ferromagnetic electrodes and the tunnel barrier of the MTJ by employing the material combination of CoFeB-MgO, a system widely adopted to produce a giant tunnel magnetoresistance ratio in MTJs with in-plane anisotropy. This approach requires no material other than those used in conventional in-plane-anisotropy MTJs. The perpendicular MTJs consisting of Ta/CoFeB/MgO/CoFeB/Ta show a high tunnel magnetoresistance ratio, over 120%, high thermal stability at dimension as low as 40 nm diameter and a low switching current of 49 microA.

Molecular analysis of the cutaneous Malassezia microbiota from the skin of patients with atopic dermatitis of different severities

Cutaneous Malassezia is an exacerbating factor in patients with atopic dermatitis. We analysed the Malassezia microbiota of adult patients with head and neck atopic dermatitis of different severities (mild, moderate and severe). Of the nine human-associated Malassezia species, the number detected was similar (3.5-4.2 species per case) among the members of all severity groups. However, the ratio of the two major Malassezia species, M. globosa and M. restricta, was different in the severe group.

Mite serine protease activates protease-activated receptor-2 and induces cytokine release in human keratinocytes

BACKGROUND

House dust mites produce serine and cysteine proteases. Mite-derived proteases have been suggested to be involved in the pathogenesis of allergies; however, whether mite-derived serine protease activity can stimulate keratinocytes remains unknown.

METHODS

We examined the activation of primary human keratinocytes by serine protease-rich extract of whole mite culture and compared with that by recombinant group 1 allergens (rDer f 1 and rDer p 1), which exclusively exhibit cysteine protease activity.

RESULTS

Protease activity of whole mite culture extract (WCE), rDer f 1 and rDer p 1 induced the release of IL-8 and granulocyte-macrophage colony-stimulating factor. Protease activity of WCEs induced a significant upregulation of their mRNA expression but rDer f 1 had much less effect. Protease activity of the WCE stimulated intracellular Ca(2+) mobilization but rDer f 1 and rDer p 1 did not. The mobilization induced by agonists for the human protease-activated receptor (PAR)-2, an agonist peptide or trypsin, was diminished by pre-incubation of keratinocytes with WCE. rDer f 1 inefficiently cleaved a synthetic N-terminal peptide of PAR-2 at different sites from trypsin, but the resultant peptides did not stimulate the release of interleukin-8.

CONCLUSIONS

The results suggest that mite-derived serine protease activity may contribute to the pathogenesis of atopic dermatitis by activating keratinocytes via PAR-2 activation but cysteine protease activity of Der f 1 and Der p 1 acts via another mechanism.

[Primary lung cancer protruding into right main bronchus, successfully treated with endoscopic neodymium yttrium aluminum garnet (Nd-YAG) laser]

Endoscopic neodymium yttrium aluminum garnet (Nd-YAG) laser treatment for endobronchial obstruction originating from the tumor provides a favorable outcome. A 67-year-old male patient with a chief complaint of cough and sputum had a primary lung cancer (squamous cell carcinoma) in the upper lobe of the right lung. The tumor projected into the right main bronchus through the upper lobe bronchus, which completely occluded the lumen of right main bronchus. Middle and lower lobes showed an obstructive pneumonia caused by its obstruction. Firstly, endoscopic Nd-YAG laser treatment for patency of right main bronchus was preoperatively performed with an aim to early improvement of obstructive pneumonia Since the inflammatory findings showed markedly improvement, a right upper sleeve lobectomy could safely be performed. The resected specimen of the tumor in the right upper lobe proved to be a case of complete resection with pathological stage IIIA (T3N1M0). When preoperative lung cancer patient has an obstructive pneumonia causing by the protruding tumor into the central airway, a patency treatment of bronchial airway using endoscopic Nd-YAG laser may lead to decrease a perioperative risk.

Phase I and pharmacokinetic (PK) study of IHL-305 (pegylated liposomal irinotecan) in patients with advanced solid tumors

2547

Background: Irinotecan (CPT-11) is a prodrug of SN-38 that has antitumor activity in a wide range of solid tumors. IHL- 305 is a PEGylated-liposomal formulation of irinotecan designed to increase the therapeutic index by prolonging the duration of exposure in both plasma and tumors. IHL-305 demonstrates superior anti-tumor activity in preclinical models. Methods: Eligible patients (pts) had advanced solid tumors, ECOG ≤2, adequate organ function and no prior exposure to CPT-11. In a standard 3+3 escalation, IHL-305 was infused over 60 minutes q 28 days. UGT1A1*28 genotyping was performed with the homozygous (*28/*28) variants treated at 50% of current dose (subsequent escalation allowed). The area under the plasma concentration- time curve (AUC) of sum total (encapsulated + released) CPT-11, released CPT-11, SN-38, and SN-38 glucuronide (SN-38G) was calculated. The % CPT-11 released was calculated as the ratio of released CPT-11 AUC to sum total CPT-11 AUC x 100. The primary objectives were to determine the dose limiting toxicities (DLTs), phase II recommended dose (P2RD), and clinical pharmacology of IHL- 305. Results: 42 pts treated; homozygous wild-type (wt/wt; n=23), heterozygous (wt/*28; n=13) and homozygous variants (*28/*28; n= 6). 10 dose levels explored; 7, 14, 28, 37, 50, 67, 88, 120, 160 and 210 mg/m2. DLTs included: 1 Gr 3 acute nausea/vomiting at 67 mg/ m2 (subsequent pts received premedication), 1 Gr 3 delayed-onset diarrhea at 160 mg/m2, and 1 Gr 3 delayed nausea/vomiting and one Gr 3 febrile neutropenia at 210mg/m2. Pts received repeated courses of IHL-305 with no delays for myelosuppression or diarrhea. 7 pts had stable disease ≥ 6 cycles. The mean ± SD PK parameters are summarized in the table below. Conclusions: The MTD and P2RD of IHL-305 is 160 mg/m2 IV q 28 days. IHL-305 shows a high and prolonged exposure of sum total and released CPT-11 and SN-38.

[Table: see text]

[Table: see text]

An RF hyperthermia electrode which generates no edge effect

e22229

Background: For local hyperthermia cancer therapy, radio frequency (RF) capacitive heating with a pair of electrodes is one of the most effective methods. RF hyperthermia with a conventional 2-dimensional square plate electrode produces an ‘edge effect‘ - the focusing of the RF current resulting in focal overheating. We designed and propose a novel hemispherical-shaped RF capacitive heating electrode that generates no edge effect. Methods: A CAD simulation (COMSOL Multiphysics 3.4) was done, and current and specific absorbance ratio (SAR) distributions of both the hemispherical and the conventional square plate shape electrodes were obtained by a 3-D finite element method. Results: The hemispherical electrode generated no focusing of current distribution, nor overheating with SAR elevation, while the square plate electrode produced an edge effect with local SAR elevation. Conclusions: The hemispherical electrode showed no edge effect from focal overheating. Our new electrode may be useful for local heating in the oral or vaginal cavity in clinical use. Phantom studies with a prototype electrode should be carried out for further confirmation.

No significant financial relationships to disclose.

Unconventional superconductivity of NpPd(5)Al(2)

The high quality single crystals of NpPd(5)Al(2) with the body-centered tetragonal structure were grown by the Pb flux method. NpPd(5)Al(2) was found to be the first Np-based heavy fermion superconductor with the relatively high critical temperature T(sc) = 4.9 K. The upper critical field H(c2) is large and highly anisotropic. Corresponding to the heavy electronic state, the initial slope of H(c2) is large, but H(c2) at low temperatures is suppressed by the magnetic field, indicating a strong Pauli paramagnetic effect and the first-order transition at H(c2). These results imply that NpPd(5)Al(2) is located at the proximity of the antiferromagnetic ordering, which might be hidden by the superconductivity. The d-wave superconductivity with a spin singlet state is most likely realized in NpPd(5)Al(2).

Isolation and characterization of new microsatellite markers for rose bitterlings, Rhodeus ocellatus

The Japanese rose bitterling (Rhodeus ocellatus kurumeus) is facing imminent extinction because of hybridization and competition from an invasive alien subspecies (Rhodeus ocellatus ocellatus). Eleven new microsatellite markers for the two subspecies were developed using dinucleotide repeat specific polymerase chain reaction. The number of alleles per locus and the heterozygosity in R. o. kurumeus were lower than those in R. o. ocellatus. Most of these microsatellite markers were successfully cross-amplified in three Acheilognathinae species.

88 EXPRESSION OF ENZYMES RELATED TO HOMOCYSTEINE METABOLISM AND HOMOCYSTEINE SENSITIVITY IN BOVINE PREIMPLANTATION EMBRYOS

Homocysteine is a nonessential amino acid produced through methionine metabolism. Elevation of homocysteine levels (hyperhomocysteinemia) increases intracellular S-adenosylhomocysteine (SAH). S-adenosylhomocysteine binds to methyltransferases (MT) with greater affinity than does S-adenosylmethionine, which is the universal methyl donor used by various cellular MT, including DNA and histone MT. Thus, SAH acts as a potent competitive inhibitor of methylation reactions. Therefore, disorder of homocysteine metabolism may affect cellular homeostasis in part through the process involving methylation reactions (Williams KT and Schalinske KL 2007 J. Nutr. 137, 311–314). Despite its predicted importance, the involvement of homocysteine metabolism in pre-implantation embryonic development remains unaddressed. In the present study, the expression of enzymes related to homocysteine metabolism in bovine pre-implantation embryos and the effects of homocysteine on the post-fertilization development of these embryos in vitro were investigated. Cumulus-enclosed oocytes obtained from slaughterhouse bovine ovaries were in vitro-matured (IVM) for 22 h in modified synthetic oviduct fluid (mSOF) supplemented with 10% v/v FCS and 0.2 IU mL–1 follicle-stimulating hormone. After IVM, the oocytes were subjected to IVF with Percoll gradient-selected sperm from one bull in an mSOF-based medium for 20 h. After IVF, presumptive zygotes were freed from the cumulus cells and cultured in mSOF up to Day 8 (IVF = Day 0). All cultures were performed at 38.5°C under 5% CO2, 5% O2, and 90% N2. Total RNA was extracted from individual blastocysts on Day 7 to 8 and reverse transcribed to cDNA using oligo(dT) primer. Transcripts for methionine adenosyltransferase 2A (MAT2A), MAT2B, adenosylhomocysteinase, methionine synthase, betaine-homocysteine MT, serine hydroxymethyltransferase 1, and 5,10-methylenetetrahydrofolate reductase were examined by qualitative PCR using bovine-specific primers for each gene and the cDNA as templates. β-Actin transcripts were used as an internal control. Moreover, presumptive zygotes after IVF were cultured in mSOF supplemented with 0 (control), 10, and 100 μm homocysteine, and development to cleavage stage and blastocyst was assessed on Day 3 and Day 7 and 8, respectively. The cultures were replicated 4 times using 561 embryos. The development data were statistically analyzed by using the general linear model. Transcripts for all genes examined were detected. Homocysteine added to the culture medium of bovine IVF embryos did not affect the cleavage rate (86.8, 83.3, and 84.3% for control, 10 μm, and 100 μm, respectively); however, blastocyst rate significantly decreased (P = 0.02) on Day 7 (12.8, 9.3, and 7.5%, respectively). The blastocyst rate on Day 8 showed no difference (P = 0.33) among the groups (24.4, 20.4, and 20.1%, respectively). These results indicate that a system for homocysteine metabolism is present in bovine pre-implantation embryos and that high homocysteine levels affect the developmental kinetics of these embryos. Supported by KAKENHI.

Functional analysis of a polymorphism in the promoter region of the IL-12/23p40 gene

BACKGROUND

Human IL-12B gene on chromosome 5q31 encodes the common p40 subunit of IL-12 and IL-23. IL-12 is known to play critical roles in the generation of T-helper type 1 (TH(1)) cells, whereas IL-23 is involved in maintenance and/or population expansion of TH(17) cells. Although several reports suggested an association between a polymorphism (-6415CTCTAA/GC) in IL-12B and asthma, the molecular mechanism how this polymorphism is involved in allergic inflammation is still unclear.

METHODS

The transcription activity was analysed by reporter assay. A transcription factor binding to -6415 polymorphic site was identified by electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assay. The amount of cytokines produced from peripheral monocytes were determined by ELISA.

RESULTS

Reporter assay showed that the transcription activity of the GC allele was higher than that of the CTCTAA allele. A transcription factor Sp1 bound to the region including the GC allele with a higher affinity than that of the CTCTAA allele in EMSA. In vivo binding of Sp1 to IL-12B gene carrying -6415GC was confirmed by ChIP assay. Overexpression of Sp1 up-regulated transcription activity of promoter carrying GC allele sequence, whereas the CTCTAA promoter was not affected by Sp1. We examined the correlation between -6415CTCTA/GC polymorphism and production of cytokine IL-12/23p40, IL-12p70, and IL-23 on peripheral blood monocytes, and monocytes with the GC/GC allele exhibited significantly higher expression of IL-12p70 protein than those with the CTCTAA/CTCTAA allele (P=0.009).

CONCLUSIONS

The -6415 polymorphism is involved in cytokine production potential by affecting Sp1-mediated transcription activity.

Analysis of peripheral blood lymphocytes using flow cytometry in polymyalgia rheumatica, RS3PE and early rheumatoid arthritis

OBJECTIVE

Clinical pictures of poly-myalgia rheumatica (PMR) and remitting seronegative symmetrical synovitis with pitting edema (RS3PE) are often indistinguishable from those of early rheumatoid arthritis (RA). To investigate whether there is a difference in immunological aspects among these 3 disorders, we performed a phenotypic analysis of peripheral blood lymphocytes.

PATIENTS AND METHODS

Eleven patients with early RA, 14 with PMR and 11 with RS3PE were enrolled in this study. After separation of mononuclear cells from peripheral blood using the Ficoll-Hypaque method, surface markers and intracellular cytokines of lymphocytes were analyzed by 2- or 3-color flow cytometry.

RESULTS

Both PMR and RS3PE showed a significant decrease in CD8⁺CD25⁺ cells (p<0.05), and significant increases in CD4⁺IFN-gamma⁺IL-4- (p<0.05), CD8⁺IFN-gamma⁺IL-4- (p<0.05 and p<0.01, respectively) and CD4⁺TNF-alpha⁺ cells (p<0.05) compared with early RA. CD3⁺CD4⁺ cells were higher in PMR than in RS3PE (p<0.01), but there were no significant differences in any other phenotypes between these disorders.

CONCLUSION

A decrease in activated cytotoxic/suppressor T cells and increases in circulating Th1 and Tc1 cells may be common characteristics of PMR and RS3PE in comparison with early RA. Both disorders are clearly different from early RA, and probably belong to the same disease entity with regard to phenotypes of peripheral blood lymphocytes.

Genetic polymorphisms of tumour necrosis factor receptor superfamily 1A and 1B affect responses to infliximab in Japanese patients with Crohn's disease

BACKGROUND

Tumour necrosis factor alpha is the key inflammatory cytokine involved in the pathogenesis of Crohn's disease. Infliximab, a chimaeric monoclonal antibody of tumour necrosis factor-alpha is successfully used for the treatment of Crohn's disease, although the response to infliximab therapy differs among patients. The genetic background of the individual may partially explain the differences of the responsiveness.

AIM

To investigate whether the polymorphisms in these genes are associated with the response to infliximab treatment as tumour necrosis factor-alpha exerts its biological activity through TNF receptor superfamily 1A and 1B.

METHODS

Eighty Crohn's disease patients were enrolled in the study and classified into responder and nonresponder according to the efficacy of infliximab treatment. Single nucleotide polymorphisms of TNF receptor superfamily 1A (rs767455 and rs4149570) and TNF receptor superfamily 1B (rs1061622, rs1061624 and rs3397) were determined.

RESULTS

The minor allele carrier of rs767455 showed a significant association with a lack of efficacy compared to the major genotype (OR = 0.26; 95% CI: 0.08-0.91). A TNF receptor superfamily 1B haplotype inferred by rs1061624 and rs3397 also showed significant differences in the distribution between responder and nonresponder (P = 0.01).

CONCLUSION

These results suggest that tumour necrosis factor receptor genotypes may be involved in the different responses to infliximab in Japanese patients with Crohn's disease.

Single-shot time-resolved measurements of nanosecond-scale spin-transfer induced switching: stochastic versus deterministic aspects

Using high bandwidth resistance measurements, we study the single-shot response of tunnel junctions subjected to spin torque pulses. After the pulse onset, the switching proceeds by a ns-scale incubation delay during which the resistance is quiet, followed by a 400 ps transition terminated by a large ringing that is damped progressively. While the incubation delay fluctuates significantly, the resistance traces are reproducible once this delay is passed. After switching, the time-resolved resistance traces indicate micromagnetic configurations that are rather spatially coherent.

The effect of vitamin C supplementation on plasma concentration and urinary excretion of vitamin C in cattle

We investigated the plasma concentration and urinary excretion of vitamin C in cows supplemented with vitamin C. Five cows (mean BW = 597 kg) were allocated to a 5 x 5 Latin square design and supplemented with a vitamin C preparation coated with hydrogenated soybean oil at 0, 10, 20, 40, or 60 mg of vitamin C per kg of BW per day for 9 d. Plasma and urine samples were collected for measuring vitamin C concentration. Urinary excretion of vitamin C was expressed as the ratio of vitamin C to creatinine. Plasma vitamin C concentration and urinary vitamin C excretion increased quadratically as dietary vitamin C increased (P < 0.001); that is, the lowest dose affected neither plasma vitamin C concentration nor urinary vitamin C excretion but the plasma vitamin C concentration and urinary vitamin C excretion increased (P < 0.05) with increasing supplementation of vitamin C at greater doses. This suggests that plasma vitamin C concentration affects urinary excretion of vitamin C in cattle and that plasma vitamin C concentration exceeded the renal threshold for vitamin C in the cows receiving vitamin C at 20 mg/kg of BW per day. Furthermore, increased urinary excretion of vitamin C appears to limit plasma vitamin C concentration in response to vitamin C intake. The daily excretion of vitamin C was estimated by the reported value of daily creatinine excretion, indicating that the daily amount of vitamin C excreted into urine was more than half of supplied vitamin C. Therefore, a large part of supplied vitamin C probably escapes ruminal degradation and is absorbed but excreted into urine.

Total knee replacement for osteoarthritis of the knee with congenital dislocation of the patella

We carried out three total knee replacements with proximal realignment in two patients with severe osteoarthritis of the knee and congenital dislocation of the patella. During the operation, the femur and the tibia were cut according to the recommendations of the manufacturer of the implant. The femoral component was placed in external rotation and the centre of the tibial component aligned in relation to the tibial tuberosity with regard to rotation and translation. After making the bone cuts, the iliotibial tract was detached from Gerdy’s tubercle, the popliteus tendon divided, and the biceps femoris tendon elongated by Z-plasty. After the trial implants were positioned, a proximal re-alignment procedure was performed. One knee had deep infection. There was one dislocated patella which was repositioned, and walking ability was improved in all knees. We believe that the rotational alignment of a prosthesis is as important as the soft-tissue surgery.

Cathelicidin LL-37 induces the generation of reactive oxygen species and release of human alpha-defensins from neutrophils

BACKGROUND

Psoriasis is characterized by epidermal infiltration of neutrophils that destroy invading microorganisms via a potent antimicrobial arsenal of oxidants and antimicrobial agents. In contrast to atopic dermatitis, psoriasis exhibits low levels of skin infections due to the presence of antimicrobial agents, including cathelicidin LL-37. LL-37 kills a broad spectrum of microbes, and activates neutrophil chemotaxis.

OBJECTIVE

To determine whether or not LL-37 could regulate additional neutrophil functions such as production of cytokines/chemokines, reactive oxygen species and release of neutrophil antimicrobial peptides.

METHODS

Human peripheral blood neutrophils were used in this study. The production of interleukin (IL)-8 and release of alpha-defensins were analysed by enzyme-linked immunosorbent assay, and real-time polymerase chain reaction (PCR) was used to quantify alpha-defensin gene expression. Phosphorylation of mitogen-activated protein kinase (MAPK) was determined by Western blotting. The generation of reactive oxygen species was examined using flow cytometry, and intracellular Ca(2+) mobilization was measured using a calcium assay kit.

RESULTS

LL-37 enhanced the production of IL-8 under the control of MAPK p38 and extracellular signal regulated kinase (ERK), as evidenced by the inhibitory effects of p38 and ERK1/2 inhibitors on LL-37-mediated IL-8 production. Furthermore, LL-37 induced phosphorylation of p38 and ERK. We also revealed that LL-37 stimulated the generation of reactive oxygen species dose- and time-dependently, most probably via NADPH oxidase activation and intracellular Ca(2+) mobilization. Finally, LL-37 induced both mRNA expression and protein release of alpha-defensins, known as human neutrophil peptide 1-3.

CONCLUSION

Taken together, we suggest that in addition to its microbicidal properties, LL-37 may contribute to innate immunity by enhancing neutrophil host defence functions at inflammation and/or infection sites.

Time and cost involved in the care of newly registered patients with diabetes mellitus and other lifestyle diseases at diabetes clinics in Japan (JDDM 4)

AIMS

To study the time and cost involved in the care of newly registered outpatients with Type 2 diabetes mellitus (DM), compared with patients with hypertension and/or hyperlipidaemia (HTL).

METHODS

A total of 313 patients with DM and 58 patients with HTL without diabetes were registered on their first visits to 11 diabetes clinics across Japan. The time and cost involved in their care was recorded over the following 5 months.

RESULTS

In the first 3 months, there was an extensive time commitment to both groups. The time spent by physicians was 1.5 times longer for DM than for HTL. The total care time spent by all the care providers for DM was twice that for HTL. The cost of DM care was twice that for HTL, with the cost of medicines excluded. However, half of the cost for DM was for laboratory tests. When these were excluded, and the remaining cost divided by the time spent, the amount for DM was half of that for HTL. Over the 5 months, mean glycated haemoglobin (HbA(1c)) in DM patients improved from 8.0% to 6.5%, and 72% of DM patients achieved the glycaemic target of HbA(1c) < or = 6.5%.

CONCLUSIONS

DM care in a diabetes clinic requires a great deal more time and resources than HTL to achieve the best outcome. An educational system for self care, presently lacking in the primary care setting in Japan, would improve glycaemic control for DM patients in the community.

Retinoid receptor-specific agonists regulate bovine in vitro early embryonic development, differentiation and expression of genes related to cell cycle arrest and apoptosis

A major goal in reproductive biotechnology is the identification of pathways that regulate early embryonic development and the allocation of cells to the inner cell mass (ICM) and trophectoderm (TE). Retinoids regulate the development and differentiation of the bovine blastocyst in vitro, although the involvement of the retinoid X receptors (RXRs) remains to be clarified. This paper compares the effect of a synthetic RXR agonist (LG100268; LG) with that of the retinoic acid receptor (RAR) agonist all-trans retinoic acid (ATRA) on blastulation. In vitro-produced morulae were treated for 48 h with LG (0.1 microM, 1 microM and 10 microM), ATRA 0.7 microM, or no additives. Treatment with ATRA did not increase the rate of development; however, the LG 0.1 microM treatment increased both the blastocyst development and hatching rate. Cell numbers increased in the ICM with LG 10 microM, while a dose-dependent reduction was observed in the TE in the presence of LG. Gene expression levels of p53 and p66 did not vary with LG but increased with ATRA. Both LG and ATRA activated bax, a pro-apoptotic gene and H2A.Z, a cell cycle-related gene. The above effects suggest the existence of active p53-dependent and -independent apoptotic pathways for ATRA and LG, respectively, in the bovine embryo. The expression of p53 and H2A.Z showed a strong, positive correlation (r=0.93; p<0.0001) in all experimental groups; both proteins are linked through the cell cycle. Agonists of RXR could be used to control blastocyst development and differentiation.

Autonomous catheter insertion system using magnetic motion capture sensor for endovascular surgery

BACKGROUND

In order to reduce fluoroscope usage in endovascular surgery, there is a need to develop autonomous catheter insertion systems.

METHODS

We propose a system for tracking the position and speed of a catheter using a magnetic motion capture sensor to provide feedback to a catheter-driving mechanism, to perform autonomous catheter insertion in major vasculature. Catheter insertion speed control and path reconstruction experiments were performed with the system inside a silicone model of major vasculature to simulate surgery.

RESULTS

The system controlled the catheter for speeds of 6.14 mm/s and reproduced a two-dimensional path inside the silicone blood vessel phantom with less than 7 mm of error.

CONCLUSIONS

We found that error in speed control rises as a result of friction between the catheter and the model wall. Path reconstruction error depends on the model's cross-sectional diameter, the properties of the catheter insertion mechanism, the magnetic sensor and the system guidance technique.

48 EFFECTS OF TRICHOSTATIN A ON DEVELOPMENT OF BOVINE SOMATIC CELL NUCLEAR TRANSFER EMBRYOS

Although cloning by somatic cell nuclear transfer (SCNT) has been achieved in various mammalian species, its efficiency has been very low (Han et al. 2003 Theriogenology 59, 33–44). Successful cloning requires conversion from differentiated donor nuclei to embryonic nuclei after transfer of the somatic nuclei into enucleated oocytes. Reprogramming of the transferred somatic nuclei must be completed by the time when normal activation of the embryonic genome occurs (Solter 2000 Nat. Rev. Genet. 1, 199–207). Recently, both full-term development and pre-implantation development of mouse SCNT embryos were significantly enhanced by treatment with trichostatin A (TSA), an inhibitor of histone deacetylase (Kishigami et al. 2006 Biochem. Biophys. Res. Commun. 340, 183–189; Rybouchkin et al. 2006 Biol. Reprod. 74, 1083–1089). The objective of this study was to investigate the effects of TSA on the development of bovine SCNT embryos. Bovine fibroblasts were cultured under serum starvation (0.4% FCS) for 7 days and then used as donor cells. The cells were electro-fused with bovine enucleated matured oocytes, and activated with a calcium ionophore and cycloheximide. They were subsequently cultured in mSOF medium until 168 h post-activation (hpa). The NT embryos were exposed to 0 (control), 5, 50, and 500 nM TSA from the start of activation to 48 hpa. Experiments were repeated 3 times, and the data were analyzed with Fisher's PLSD test following ANOVA. The cleavage rates were the same among the groups (60 to 80&percnt;; P &gt;0.05). However, the blastocyst rate of NT embryos treated with 50 nM TSA was higher than that of control embryos (40&percnt; vs. 19&percnt;, respectively; P &lt; 0.05). On the other hand, the blastocyst rate was lower with 500 nM TSA than with 5 or 50 nM TSA (7&percnt; vs. 33&percnt; or 40&percnt;; P &lt; 0.05). These data suggest that proper TSA treatment after somatic cloning improves the rate of development of bovine cloned embryos to the blastocyst stage. Further research is needed to examine whether NT embryos derived from different cell lines or types have similar susceptibility to TSA.

44 NUCLEAR TRANSFER IN CATTLE USING SOMATIC CELLS FROM FROZEN TESTICLES WITHOUT CRYOPROTECTANTS

Obtaining somatic cells from preserved organs or tissues is useful for the conservation and regeneration of genetic resources by nuclear transfer (NT). Bovine cells for NT have been obtained from cooled carcasses stored at 0�C for several days (Arat et al. 2005 Reprod. Fert. Dev. 17, 164 abst) and from fetal skin tissue cryopreserved with DMSO (Fahrudin et al. 2001 J. Vet. Med. Sci. 63, 1151–1154). However, frozen storage of organs or tissues without cryoprotectants was considered to be quite inappropriate for obtaining viable cells. We report here that viable donor cells for NT were obtained from bovine testicles after frozen storage without cryoprotectants. In the first experiment, we investigated whether viable cells can be recovered from frozen testicles castrated from Japanese Black bulls. The testicles were frozen at -80�C in a freezer for several days; then some were stored in liquid nitrogen for 10 months without cryoprotectants. Before thawing, the testicles were divided into 3 pieces, caput epididymis, cauda epididymis, and testis. Each piece was then put in saline at 42�C for quick thawing. Thawed tissues were minced into 5-mm pieces and incubated at 39�C for 2 h in DMEM containing 0.1% collagenase and 0.2% dispase. After filtration through a 250-�m nylon mesh filter, the filtrates were centrifuged at 250 � 4g for 5 min. Then precipitates were resuspended with MF-start� primary culture medium (TM Cell Research Inc., Fukui, Japan) and incubated at 38.5�C under the atmosphere of 5% CO2 in air with high humidity. After 5 days of incubation, the medium was replaced and nonadherent debris was discarded. Viable cells were obtained from the caput epididymis. These cells actively proliferated and expanded. In the next experiment, to determine whether these cells can be used for NT, the cells were electrically fused with enucleated bovine oocytes. Bovine fibroblasts taken from unfrozen ear tissue were used as controls. The NT embryos were activated by Ca-ionophore treatment, followed by treatment with cycloheximide for 6 h, and then cultured in mSOF for 168 h. NT embryos reconstructed from testicle cells did not significantly differ from NT embryos made with control cells with regard to blastocyst rates (22.1% and 20.2%), cell number of blastocysts [130 � 43 and 121 � 43 (mean � SD)], and ICM ratio (21.1% and 22.6%), respectively (ANOVA). These results suggest that somatic cells derived from bovine frozen testicles can be used for nuclear transfer. Further studies are needed to examine whether viable cells can be obtained from other frozen organs or tissues. This study was partially supported by a grant from the Wakayama Prefecture Collaboration of Regional Entities for the Advancement of Technological Excellence, JST.

298 EFFECTS OF TRICHOSTATIN A DURING IN VITRO FERTILIZATION OF BOVINE OOCYTES ON SUBSEQUENT DEVELOPMENT, CELL NUMBER, AND ALLOCATION OF RESULTING EMBRYOS

Histone acetylation is one of the major mechanisms of epigenetic reprogramming of gamete genomes after fertilization or of transferred cell genomes after nuclear transfer to establish a totipotent state for normal development. In the fertilization of bovine oocytes, asynchronous histone acetylation occurs during pronuclear formation in the manner that modification of the paternal genome precedes that of the maternal genome (Wee et al. 2006 J. Biol. Chem. 281, 6048–6057). In the present study, the effects of trichostatin A (TSA), an inhibitor of histone deacetylase, during in vitro fertilization (IVF) of bovine oocytes on subsequent embryonic development were investigated. Cumulus-enclosed oocytes obtained from slaughterhouse ovaries were in vitro-matured (IVM) for 21 h in TCM-199 supplemented with 5% v/v FCS, 0.5 mM sodium pyruvate, 0.02 AU mL-1 FSH, and 1 �g mL-1 estradiol-17β at 39�C under 5% CO2 in air. After IVM, the oocytes were subjected to IVF with 3 � 106 mL-1 of Percoll gradient-selected sperm in a defined medium (Brackett and Oliphant 1975 Biol. Reprod. 12, 260–274) supplemented with 0 (control), 5, 50, and 500 nM TSA for 18 h. After IVF, presumptive zygotes were freed from cumulus cells and cultured in mSOF medium until 168 h post-insemination (hpi) at 39�C under 5% CO2, 5% O2, and 90% N2 with high humidity. Cleavage and blastocyst development were assessed at 48 and 168 hpi, respectively. Inner cell mass (ICM) and trophectoderm (TE) of blastocysts were differentially stained by the method of Thouas et al. (2001 Reprod. Biomed. Online 3, 25–29) to assess cell number and ICM/TE ratio. Experiments were replicated 3 times. Data are presented as means � SEM and statistically analyzed by multiple comparison with the Holm method. Rates of cleavage (0 nM: 71.0 � 7%, n = 102; 5 nM: 75.5 � 5%, n = 106; 50 nM: 68.8 � 6%, n = 105; and 500 nM: 71.7 � 4%, n = 98) and blastocyst formation (21.4 � 5%, 22.3 � 6%, 17.8 � 2%, and 18.2 � 2%, respectively) were similar among the groups. However, 500 nM TSA significantly (P &lt; 0.05) increased ICM and total cell numbers (59.8 � 4 and 143.5 � 7, respectively, n = 31) compared with the control (43.1 � 3 and 120.9 � 7, n = 31). In addition, ICM/TE ratios were higher in the 50 nM (0.81 � 0.08, n = 29) and 500 nM (0.92 � 0.2, n = 31) groups than in the control (0.59 � 0.04, P &lt; 0.05). These results suggest that TSA treatment during IVF of bovine oocytes does not affect the blastocyst rate but alters the cell numbers and their allocation to ICM and TE. Overriding epigenetic modification of the genome during fertilization may have a carryover effect on cell proliferation and differentiation in pre-implantation embryos. This study was supported by a grant from Wakayama Prefecture Collaboration of Regional Entities for the Advancement of Technological Excellence, JST.

NMR evidence for higher-order multipole order parameters in NpO2

We report a microscopic investigation of multipolar order parameters in the ordered state of NpO2 conducted via 17O NMR on a single crystal. From the angular dependence of hyperfine fields at 17O nuclei, we have obtained clear evidence for the appearance of field-induced antiferro-octupolar as well as field-induced antiferro-dipolar moments below T0 = 26 K. We have also observed oscillatory spin-echo decay, which is well understood in terms of small electric field gradients created by antiferro-quadrupolar ordering. This reveals that the quadrupolar order parameter is directly observable by means of NMR. The present NMR studies provide definitive support for a proposed longitudinal triple-q type octupolar-quadrupolar ordering model for NpO2.

Muscle type-specific response of PGC-1 alpha and oxidative enzymes during voluntary wheel running in mouse skeletal muscle

AIM

It is generally accepted that endurance exercise increases the expression of peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha), which governs the expression of oxidative metabolic enzymes. A previous report demonstrated that the regulation of mitochondrial protein expression in skeletal muscles in response to cold exposure depends on muscle fibre type. Cold exposure and endurance exercise are both metabolic challenges that require adjustments in mitochondrial energy metabolism, we hypothesized that the exercise-induced increase in oxidative enzymes and PGC-1alpha expression is higher in fast-type than in slow-type muscle.

METHODS

Female ICR mice were individually housed in cages equipped with running wheel for 1, 2, 4, 6 or 8 weeks. The soleus, plantaris (PLA) and tibialis anterior (TA) muscles were then prepared from each mouse. The expression levels of PGC-1alpha, mitochondrial proteins and GLUT4 were evaluated by Western blotting.

RESULTS

The expression level of PGC-1alpha was increased only in the PLA muscle. Furthermore, the expression levels of all mitochondrial proteins and GLUT4 in the PLA muscle were increased. In the TA muscle, although there was no increase in PGC-1alpha expression, the expression levels of mitochondrial proteins and GLUT4 were increased.

CONCLUSIONS

These results suggest that muscle type-specific responses occur during endurance exercise, and that the increase in PGC-1alpha expression is not the only factor that promotes oxidative capacity as a result of endurance exercise.

Apoptosis-independent Poor Morphology of Bovine Embryos Produced by Multiple Ovulation

In multiple ovulation and embryo transfer (MOET) programmes in cattle, a considerable number of morphologically poor-quality embryos continue to be produced; this is one of the limiting factors of the technique. Apoptosis has often been implicated in developmental arrest and fragmentation; these are regarded as poor traits of embryonic quality in mammalian pre-implantation embryos. In the present study, apoptosis was assessed in morphologically poor-quality embryos in comparison with good-quality embryos that were recovered from a MOET programme. Retarded embryos (two to 16 cell stage), morulae with severe fragmentation and morphologically good-quality morulae recovered from superstimulated cows at day 7 post-insemination were subjected to TdT-mediated dUTP nick-end labelling (TUNEL) and Hoechst staining. Cell nuclei that showed both TUNEL staining and apoptotic morphology were considered to be apoptotic. Apoptotic index (AI) was calculated as the percentage of apoptotic cells per embryo. Fifteen of 17 retarded embryos and 10 of 15 morphologically poor-quality morulae did not show signs of apoptosis. The mean AIs in the morphologically poor-quality embryos (two to 16 cell stage, 2.2%; poor morulae, 1.3%) were as low as that in the good-quality embryos (2.9%). These results suggest that another mode of developmental arrest and/or fragmentation that is independent of apoptosis occurs in morphologically poor-quality embryos recovered from MOET programmes.

Abilities of cumulus and granulosa cells to enhance the developmental competence of bovine oocytes during in vitro maturation period are promoted by midkine; a possible implication of its apoptosis suppressing effects

We previously reported that when midkine (MK), a heparin-binding growth differentiation factor was used inin vitromaturation (IVM) culture of bovine cumulus-enclosed oocytes (CEOs), their developmental competence to the blastocyst stage afterin vitrofertilization (IVF) was enhanced and the effect of MK might be mediated by its action upon mural granulosa cells and cumulus cells that closely surround the oocyte. In the present study, when denuded oocytes (DOs) were matured in IVM medium with or without MK (200 ng/ml) in the presence or absence of isolated cumulus cell masses and subjected to IVF, the enhancing effects of MK on the developmental competence of DOs to the blastocyst stage after IVF were exerted only in the presence of cumulus cells. In addition, we prepared the conditioned media of granulosa cells cultured with or without 200 ng MK/ml (CMMK+ or CMMK− respectively) and examined their effects on the IVM of DOs in terms of their developmental competence to the blastocyst stage after IVF. The supplementation of CMMK+ into IVM medium at 40% (v/v) significantly enhanced the blastocyst development compared with the no additive control and the CMMK− supplemented groups. Furthermore, the effects of MK during IVM of bovine CEOs on the cumulus cell apoptosis were investigated. CEOs were cultured up to 24 h in IVM medium without (control) or with 200 ng MK/ml. The genomic DNA was extracted from CEOs at 0, 6, 12, 18 and 24 h of IVM and subjected to ligation-mediated PCR (LM-PCR) to detect the apoptotic internucleosomal DNA fragmentation. DNA fragmentation was scarcely detected at the start of IVM, whereas it increased time-dependently as the IVM culture progressed. The degree of the fragmentation was significantly lower in the MK-treatment group compared with the control group at 18 and 24 h of IVM. The apoptosis-suppressing effect of MK on cumulus cells was further confirmedin situby using TUNEL on CEOs. In conclusion, data from the present study further confirmed that MK enhances the developmental competence of bovine oocytes via cumulus and granulosa cells. It was also demonstrated that MK suppresses the apoptosis that occurs in cumulus cells during the period of IVM of bovine CEOs. The putative soluble factor(s) from cumulus cells was suggested from the experiment using CMMK+ . MK may promote the production of such factors in part by its anti-apoptotic effects on cumulus cells.