Impacts of dosing and drug withdrawal period on tacrolimus-based triple therapy in a non-human primate renal transplantation model

Non-human primate (NHP) renal transplantation models are widely used vivo models for researching new immunosuppressive therapies including allograft tolerance strategies. To enroll animals into a tolerance study, an immunosuppressive regimen that efficiently establishes stable renal function in NHPs is needed. Here, we assessed the effect of triple therapy comprising 2.0 mg/kg tacrolimus, mycophenolate mofetil and a steroid and its success rate for achieving stable renal function. In addition, to predict the pathophysiological consequences of withdrawing immunosuppressants, an indispensable process after induction of tolerance, we also assessed changes in the stable renal state maintained by triple therapy after drug withdrawal. Six cynomolgus monkeys were used. The median survival time was >176 days over the dosing period and 45 days after drug withdrawal. The triple therapy successfully induced stable graft function without calcineurin inhibitor nephrotoxicity in three of six recipients, although adopting trough-dependent tacrolimus dose adjustment rather than a preset dose regimen could improve on the present strategy. Further, drug withdrawal led to deterioration of renal function, de novo donor specific antibody production and increased the memory/naïve T cell ratio within two weeks post drug withdrawal. We expect that these findings contribute to establish one of the choices for animal model for evaluating future tolerance therapy for renal transplantation.

Enhanced exudation of malate in the rhizosphere due to AtALMT1 overexpression in blackgram (Vigna mungo L.) confers increased aluminium tolerance

Worldwide, 50% of soil is acidic, which induces aluminium (Al) toxicity in plants, as the phyto-availability of Al³⁺ increases in acidic soil. Plants responds to Al³⁺ toxicity by exuding organic acids into the rhizosphere. The organic acid responsible for Al³⁺ stress response varies from species to species, which in the case of blackgram (Vigna mungo L.) is citrate. In blackgram, an Arabidopsis malate transporter, AtALMT1, was overexpressed with the motive of inducing enhanced exudation of malate. Transgenics were generated using cotyledon node explants through Agrobacterium tumefaciens-mediated transformation. The putative transgenics were initially screened by AtALMT1-specific genomic DNA PCR, followed by quantitative PCR. Two independent transgenic events were identified and functionally characterized in the T₃ generation. The transgenic lines, Line 1 and 2, showed better root growth, relative water content and chlorophyll content under Al³⁺ stress. Both lines also accounted for less oxidative damage, due to reduced accumulation of ROS molecules. Photosynthetic efficiency, as measured in terms of F_v /F_m , NPQ and Y(II), increased when compared to the wild type (WT). Relative expression of genes (VmSTOP1, VmALS3, VmMATE) responsible for Al³⁺ stress response in blackgram showed that overexpression of a malate transporter did not have any effect on their expression. Malate exudation increased whereas citrate exudation did not show any divergence from the WT. A pot stress assay found that the transgenics showed better adaptation to acidic soil. This report demonstrates that the overexpression of a malate transporter in a non-malate exuding species improves adaptation to Al³⁺ toxicity in acidic soil without effecting its stress response mechanism.

Sedative and physiological effects of alfaxalone intramuscular administration in cynomolgus monkeys (Macaca fascicularis)

To evaluate the sedative and physiological effects of alfaxalone intramuscular (IM) administration, 12 healthy cynomolgus monkeys were administered single IM doses of alfaxalone at 0.625 mg/kg (ALFX0.625), 1.25 mg/kg (ALFX1.25), 2.5 mg/kg (ALFX2.5), 5 mg/kg (ALFX5), 7.5 mg/kg (ALFX7.5), or 10 mg/kg (ALFX10); saline was used as the control (CONT). The sedative effects were subjectively evaluated using a composite measure scoring system in six animals. Changes in respiratory rate, pulse rate, non-invasive blood pressure, percutaneous oxygen-hemoglobin saturation (SpO₂), and rectal temperature were observed after IM treatments in the other six animals. All animals were allowed to lay down following the ALFX5, ALFX7.5, and ALFX10 treatments, whereas lateral recumbency was achieved in only two animals after ALFX2.5 treatment and none after the CONT, ALFX 0.625, and ALFX1.25 treatments. The median time (interquartile range) to lateral recumbency was 6.5 min (5.3–7.8), 4.0 min (4.0–4.0), and 3.0 min (3.0–3.8), and the duration of immobilization was 27.5 min (19.0–33.8), 56.0 min (42.3–60.8), and 74.5 min (62.8–78.0) after the ALFX5, ALFX7.5, and ALFX10 treatments, respectively. Endotracheal intubation was achieved in all six animals after the ALFX7.5 and ALFX10 treatments. Dose-dependent decreases in respiratory rate, non-invasive blood pressure, SpO₂, and rectal temperature were observed, and the quality of recovery was smooth in all animals after the ALFX5, ALFX7.5, and ALFX10 treatments. Thus, alfaxalone IM induced a dose-dependent sedative effect in cynomolgus monkeys, but at higher doses, hypotension, hypoxemia, and hypothermia could be induced.

Carrier and spin dynamics of high-density exciton magnetic polarons in Cd0.8Mn0.2Te

We investigated the carrier and spin dynamics of high-density exciton magnetic polarons (HD-EMPs) in Cd_0.8Mn_0.2Te based on the measurement of their time-resolved photoluminescence (PL) spectra and polarization states, and the utilization of photo-induced Faraday rotation techniques. The PL from the HD-EMPs were collected in a forward scattering configuration, and was observed as a pulsed emission of a few picoseconds duration, exhibiting a blue-shift with time evolution. The blue shift originated from the refractive-index dispersion of the sample. By excluding the influence of the refractive-index dispersion on the time profile, it was revealed that the ultra-short pulsed emission with a time width smaller than 1 ps was initially radiated with a time delay of ~2.4 ps after photoexcitation. From the results of time evolution of the polarization states, it is concluded that the exciton-Mn spin interactions occurs immediately after the excitation, which causes the Mn ion spins to align to follow the spin states of photoexcited excitons. The alignment of the Mn ion spins through the formation of the HD-EMPs was significantly faster than that of the localized EMP. On the other hand, the time evolution of the photo-induced Faraday rotation showed two decay components attributed to spin relaxations of the excitons and Mn ions within the HD-EMP. The observation of the Faraday rotation signal due to the Mn ion spins further confirms that these spins were aligned by the photo-excited spin-aligned excitons. Our findings suggest a novel mechanism for the effective optical control of spins in a semimagnetic semiconductor, which is associated with a multi-exciton system and its localized state.

Abstract P4-01-23: Clinical significance of serum PSA in breast cancer patients

Background: Recent preclinical data suggest that estrogen receptor (ER) positive breast cancer (BC), may switch from dependence on ER to androgen receptor (AR) as possible mechanism of resistance to ER-targeted endocrine therapy. AR dependency has also been suggested in a subset of ER-, AR+ BC. Based on these findings, clinical trials testing AR-targeting therapies in BC have been conducted. However, predictive markers for response to this type of therapies remain to be elucidated. PSA is the product of an androgen-responsive gene produced also in BC, and serum PSA (sPSA) could be detected in BC patients by a highly sensitive assay. Hypothesis:If sPSA reflects AR dependency of BC, it might be useful as a predictive marker for response to AR-targeting therapy. Methods:In this study, we investigated whether tumor-derived sPSA could be detected in BC patient, and if it might reflect tumor biology. In metastatic breast cancer (MBC) patients continuously observed, sPSA was evaluated monthly by CLEIA method (detection sensitivity ≥ 3 ng/L). Similarly, sPSA was evaluated at arbitrary points in non-BC control and point analysis BC group enrolled regardless of clinicopathological factor or treatment history. In the observational group, the relationship between change in disease condition and sPSA was analyzed. Next, correlations between sPSA and various clinicopathological factors were analyzed using combined data of point analysis group and initial sPSA value of observation group. In this study, 146 BC (26 observation group and 120 point analysis group) and 99 control were enrolled. Results: In the observational analysis, 5 cases showed sPSA change well reflected the disease condition, but not in other 5 cases. In remaining 16 cases, sPSA was undetectable or the observation period was insufficient (<4m). In the point analysis, sPSA was detected in 28.3% and 28.1% in control and BC respectively. Although in pre-menopausal state, there was no significant difference in sPSA between control and BC (4.4 ± 6.98 ng/L vs 3.7 ± 5.5 ng/L), in post-menopausal state, sPSA was significantly higher in BC compared with control (0.7 ± 2.5 ng/L vs 64.6 ± 357.4 ng/L; P<0.05). In analysis limited to post-menopausal BC, sPSA was higher in MBC (de-novo stage 4 and recurrence) compared with non-MBC (Stage0-3) (106.0 ± 457.2 ng/L vs 2.1 ± 8.5 ng/L; P<0.05). Similarly, sPSA was higher in low ki-67 (<20%) cases compared with high ki-67 (≥20%) (105.7 ± 510.8 ng/L vs 30.5 ± 173.7 ng/L; p<0.05). There was no significant difference in sPSA due to histological type, ER or HER2 status and nuclear grade. In correlation analysis of quantitative data limited to post-menopausal MBC, sPSA was negatively correlated with Ki-67 (rS=-0.35, p<0.05) and positively correlated with treatment line of previous endocrine therapy (rS=0.27, p<0.05). It did not correlate with age, disease free interval, number of metastatic organs or treatment line of previous chemotherapy. Conclusion:Our data suggest that sPSA may be tumor-derived at least in post-menopausal MBC and may reflect some kind of tumor biological properties. These all findings justify further studies of the efficacy of sPSA as a predictive marker in AR-targeted therapy.

Citation Format: Hanamura T, Ohno K, Houkibara S, Murasawa H, Nakamura T, Watanabe H, Kaizuka M, Sawano S, Koyama H, Ito K-i. Clinical significance of serum PSA in breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-01-23.

GhSTOP1, a C2H2 type zinc finger transcription factor is essential for aluminum and proton stress tolerance and lateral root initiation in cotton

Aluminum (Al) and proton (H⁺ ) ions are major acid soil stress factors deleteriously affecting plant root growth and crop yield. In our preliminary studies, cotton (Gossypium hirsutum L.) seedlings displayed very sensitive phenotypes to Al and H⁺ rhizotoxicities. Based on previous Arabidopsis results, we aimed to characterise the Al stress responsive Sensitive to Proton rhizotoxicity 1 (GhSTOP1) transcription system in cotton using RNAi-mediated down-regulation. With the help of seed embryo apex explants, we developed transgenic cotton plants overexpressing a GhSTOP1-RNAi cassette with NPTII selection. Kanamycin-tolerant T1 seedlings were further considered for Al and H⁺ stress tolerance studies. Down-regulation of the GhSTOP1 increased sensitivity to Al and proton rhizotoxicities, and root growth was significantly reduced in RNAi lines. The expression profile of GhALMT1 (Aluminum-activated Malate Transporter 1), GhMATE (Multidrug and Toxic Compound Extrusion), GhALS3 (Aluminium Sensitive 3) and key genes involved in the GABA shunt were down-regulated in the transgenic RNAi lines. Additionally, the lateral root initiation process was delayed and expression of GhNAC1, which is involved in lateral roots, was also suppressed in transgenic lines. Besides, overexpression of GhSTOP1 in Arabidopsis accelerated root growth and AtMATE and AtALMT1 expression under Al stress conditions. These analyses indicate that GhSTOP1 is essential for the expression of several genes which are necessary for acid soil tolerance mechanisms and lateral root initiation.

Effects of housing conditions on behaviors and biochemical parameters in juvenile cynomolgus monkeys (Macaca fascicularis)

To investigate the effects of environmental enrichment on laboratory monkeys, we studied behavioral and physiological differences following changes in housing conditions. Ten male and female juvenile cynomolgus monkeys were first housed in pairs for 8 weeks after quarantine/acclimatization (singly housed) and subsequently housed alone for the next 8 weeks. Monkeys were subjected to evaluations of body weight gain, stereotypic or affiliative behaviors, cortisol, 4-ethylphenyl sulfate (4EPS) and catecholamine concentrations in biological samples, and blood chemistry tests under both housing conditions. Under paired housing, the stereotypic behavioral score decreased in both sexes, and the affiliative behavioral score increased in males and showed an increasing trend in females. Under single housing, the stereotypic score increased in both sexes, and the affiliative score decreased in males. Paired housing decreased serum calcium and urine cortisol concentrations in both sexes and decreased plasma cortisol in males and plasma 4EPS concentrations in females. The stereotypic score was positively correlated with serum calcium, plasma and urine cortisol, and plasma 4EPS concentration and negatively correlated with the affiliative score. The feces painting score, affiliative score, and plasma cortisol and serum calcium concentrations showed sex differences, suggesting differences in responsiveness to environmental changes between males and females. In conclusion, paired housing improved behavioral abnormalities in juvenile cynomolgus monkeys, suggesting that it may be an effective environmental enrichment paradigm. Calcium, cortisol, and 4EPS concentrations in biological samples may be useful indices for evaluating the effects of environmental enrichment.

Myocardial torsional deformations in cats with hypertrophic cardiomyopathy using two-dimensional speckle-tracking echocardiography

OBJECTIVES

The objective of our study was to quantitatively measure systolic torsional deformations in cats with hypertrophic cardiomyopathy (HCM) and in controls.

ANIMALS

Twenty-six client-owned cats with HCM and 14 healthy cats. HCM cats were categorized based on their symptoms (asymptomatic and symptomatic) and with or without left ventricular outflow tract obstruction (obstructive and non-obstructive).

METHODS

The cats were examined for myocardial deformations using two-dimensional speckle-tracking echocardiography and were evaluated for peak systolic rotation and the rotation rate at each basal and apical view. Cats were also evaluated for the peak systolic torsion and torsion rate.

RESULTS

The peak systolic apical rotation and torsion were higher in asymptomatic and symptomatic cats with HCM than in control cats. Also, the peak systolic apical rotation, apical rotation rate, torsion, and torsion rate were higher in cats with obstructive HCM than in control cats.

CONCLUSIONS

Myocardial torsional deformations assessed by two-dimensional speckle-tracking echocardiography may be useful for evaluating compensatory myocardial function of HCM.

Poorly Differentiated Rectal Carcinoid in a Cow

A carcinoid tumor was found as a solitary soft mass in the wall of the rectum adjacent to the anorectal junction in an adult Holstein cow. Microscopically, the tumor involved the submucosa and partly invaded the muscular layer. It consisted of a compact arrangement of a great number of large polygonal cells and a small number of small dark cells, some of which showed argyrophilia (Grimelius positive). Immunohistochemically, both types of tumor cells were positive for vimentin, keratin, and S-100 protein and weakly positive for neuron-specific enolase (NSE), whereas they were negative for some endocrine markers such as chromogranin A, insulin, glucagon, somatostatin, serotonin, adrenocorticotropic hormone, and calcitonin. Electron microscopy revealed membrane-bound secretory granules in the cytoplasm of some small dark cells. In such a poorly differentiated carcinoid, the morphologic characteristics of the small dark cells were strong evidence for the diagnosis. This is the first description of a poorly differentiated carcinoid developing in the rectum of a cow.

Effect of road transportation on the serum biochemical parameters of cynomolgus monkeys and beagle dogs

To determine the effect of long-distance (approximately 600 km) road transportation on the blood biochemistry of laboratory animals, we investigated the changes in serum biochemical parameters in healthy cynomolgus monkeys and beagle dogs transported by truck from Osaka to Tsukuba, Japan. The concentrations of serum cortisol, total bilirubin and aspartate aminotransferase in monkeys increased during transportation. Serum cortisol and total bilirubin levels in dogs also increased during transportation, but serum triglyceride decreased. Serum parameter values in truck-transported monkeys and dogs returned to baseline levels within two weeks following arrival. Taken together, these results suggest that a two-week acclimation period is the minimum duration required for adaptation following road transportation.

Involvement of trace elements in the pathogenesis of prion diseases

Prion diseases are progressive neurodegenerative diseases that are associated with conformational changes that convert normal cellular prion protein (PrP(C)) into an abnormal pathogenic prion protein (PrP(Sc)). It is widely recognized that prion diseases are forms of transmissible amyloidosis and are considered to be protein-misfolding diseases (conformational diseases), a category that also includes Alzheimer's disease. Trace elements play crucial roles in the conformational change affecting PrP(C), and increasing evidence suggests that PrP(C) is a metal-binding protein that is involved in the homeostasis of Cu, Zn, and Fe. In this article, we review the current understanding of links between trace elements and the conformational change to PrP(Sc), based on our studies using synthetic prion peptides, as well as other new findings. We also focus on PrP(Sc)-induced disruption of Ca homeostasis as a molecular mechanism for neurodegeneration in prion diseases. Possible roles of carnosine (ß-alanyl histidine) as a candidate neuroprotective substance use in prion diseases are also discussed.

Quantitative and antioxidative behavior of Trolox in rats' blood and brain by HPLC-UV and SMFIA-CL methods

Trolox, a water-soluble vitamin E analogue has been used as a positive control in Trolox equivalent antioxidant capacity and oxygen radical antioxidant capacity assays due to its high antioxidative effect. In this study, the ex vivo antioxidative effects of Trolox and its concentration in blood and brain microdialysates from rat after administration were evaluated by newly established semi-microflow injection analysis, chemiluminescence detection and HPLC-UV. In the administration test, the antioxidative effect of Trolox in blood and brain microdialysates after a single administration of 200 mg/kg of Trolox to rats could be monitored. The antioxidative effects in blood (12.0 ± 2.1) and brain (8.4 ± 2.1, × 10(3) antioxidative effect % × min) also increased. Additionally, the areas under the curve (AUC)s0-360 (n = 3) for blood and brain calculated with quantitative data were 10.5 ± 1.2 and 9.7 ± 2.5 mg/mL × min, respectively. This result indicates that Trolox transferability through the blood-brain barrier is high. The increase in the antioxidative effects caused by Trolox in the blood and brain could be confirmed because good correlations between concentration and antioxidative effects (r ≥ 0.702) were obtained. The fact that Trolox can produce an antioxidative effect in rat brain was clarified.

Effect of new training technique on affinity of cynomolgus monkeys for animal care personnel

To confirm our hypothesis that the sex and age of cynomolgus monkeys influences the effect of training, we employed a new training technique designed to increase the animal’s affinity for animal care personnel. During 151 days of training, monkeys aged 2 to 10 years accepted each 3 raisins/3 times/day, and communicated with animal care personnel (5 times/day). Behavior was scored using integers between −1 and 5. Before training, 35 of the 61 monkeys refused raisins offered directly by animal care personnel (Score −1, 0 and 1). After training, 28 of these 35 monkeys (80%) accepted raisins offered directly by animal care personnel (>Score 2). The mean score of monkeys increased from 1.2 ± 0.1 to 4.3 ± 0.2. The minimum training period required for monkeys to reach Score 2 was longer for females than for males. After 151 days, 6 of the 31 females and 1 of the 30 males still refused raisins offered directly by animal care personnel. Beneficial effects of training were obtained in both young and adult monkeys. These results indicate that our new training technique markedly improves the affinity of monkeys for animal care personnel, and that these effects tend to vary by sex but not age. In addition, abnormal behavior and symptoms of monkeys were improved by this training.

Uremic serum contains humoral factor(s) larger than fifty kilodaltons which suppresses endothelin production in cultured endothelial cells

Direct effects of human uremic serum on the production of endothelin-1 in cultured porcine endothelial cells were examined in this study. Uremic serum decreased the level of monomeric endothelin-1 secreted into the culture medium by endothelial cells. This effect occurred at a transcriptional step because uremic serum decreased the endothelin-1 mRNA level in those cells. For the partial characterization of this inhibitory activity, uremic serum was fractionated with a centricut column. Uremic serum contains humoral factor(s) larger than 50 kD which suppress the endothelin-1 mRNA level in cultured endothelial cells.

Protective activity of carnosine and anserine against zinc-induced neurotoxicity: a possible treatment for vascular dementia

Carnosine (β-alanyl-L-histidine) is a small dipeptide with numerous beneficial effects, including the maintenance of the acid-base balance, antioxidant properties, chelating agent, anti-crosslinking, and anti-glycation activities. High levels of carnosine and its analogue anserine (1-methyl carnosine) are found in skeletal muscle and the brain. Zinc (Zn)-induced neurotoxicity plays a crucial role in the pathogenesis of vascular dementia (VD), and carnosine inhibits Zn-induced neuronal death. Here, the protective activity of carnosine against Zn-induced neurotoxicity and its molecular mechanisms such as cellular Zn influx and Zn-induced gene expression were investigated using immortalised hypothalamic neurons (GT1-7 cells). Carnosine and anserine protected against Zn-induced neurotoxicity not by preventing increases in intracellular Zn(2+) but by participating in the regulation of the endoplasmic reticulum (ER) stress pathway and the activity-regulated cytoskeletal protein (Arc). Accordingly, carnosine and anserine protected against neurotoxicity induced by ER-stress inducers thapsigargin and tunicamycin. Hence, carnosine and anserine are expected to have future therapeutic potential for VD and other neurodegenerative diseases.

Increased undercarboxylated osteocalcin/intact osteocalcin ratio in patients undergoing hemodialysis

Serum undercarboxylated osteocalcin (ucOC)/intact osteocalcin (iOC) ratio increased >1.0 in the patients undergoing hemodialysis, particularly in those with high bone turnover state. Consequently, serum ucOC/iOC ratio might lose its significance as a bone metabolic marker to indicate vitamin K deficiency in hemodialysis patients.

INTRODUCTION

Serum intact osteocalcin (iOC), undercarboxylated OC (ucOC), and the ucOC/iOC ratio are considered clinically relevant indices in pre-dialysis chronic kidney disease (CKD) and hemodialysis (HD) patients, despite their accumulation in uremic serum.

METHODS

Serum iOC and ucOC were measured along with serum intact parathyroid hormone (iPTH), bone alkaline phosphatase (BAP), and tartrate-resistant acid phosphatase (TRACP)-5b in 89 pre-dialysis CKD and 189 HD patients.

RESULTS

Serum iOC and ucOC showed significantly negative correlations with estimated glomerular filtration rate in pre-dialysis CKD patients, although serum ucOC/iOC ratio did not correlate. Serum ucOC was significantly greater in HD patients than in pre-dialysis CKD patients, while serum iOC did not differ significantly, resulting in serum ucOC/iOC ratio >1.0 in 135 (71.4%) out of 189 HD patients. HD patients with high serum ucOC/iOC ratio (>1.0) had a significantly younger age and significantly higher values of body mass index, serum creatinine, albumin, phosphate, iPTH, and TRACP-5b than those with low ucOC/iOC ratio (≤ 1.0). The baseline iPTH and P1NP correlated with the changes of the ucOC/iOC ratio during the 2 days of the inter-dialytic period. Multivariate analysis showed that log [ucOC/iOC] in HD patients was significantly associated with log [iPTH], log [BAP], or log [TRACP-5b].

CONCLUSIONS

Serum ucOC/iOC ratio >1.0 was observed in as high as 71.4% of HD patients, preferentially with high bone turnover state, in comparison with pre-dialysis CKD patients. These data suggested that serum ucOC/iOC ratio might lose its significance as a bone metabolic marker to indicate vitamin K deficiency in HD patients.

Diffusion-weighted imaging vs STIR turbo SE imaging: capability for quantitative differentiation of small-cell lung cancer from non-small-cell lung cancer

OBJECTIVE

To compare the capability of differentiation of small-cell lung cancer (SCLC) from non-SCLC (NSCLC) between diffusion-weighted imaging (DWI) and short tau inversion recovery (STIR) turbo spin-echo imaging.

METHODS

The institutional review board of Kobe University Hospital, Kobe, Japan, approved this study, and written informed consent was obtained from each patient. 49 patients with NSCLC (30 males and 19 females; mean age, 66.8 years) and 7 patients with SCLC (5 males and 2 females; mean age, 68.6 years) enrolled and underwent DWI and STIR. To quantitatively differentiate SCLC from NSCLC, apparent diffusion coefficient (ADC) values on DWI and contrast ratios (CRs) between cancer and muscle on STIR were evaluated. ADC values and CRs were then compared between the two cell types by Mann-Whitney's U-tests, and the diagnostic performances were compared by McNemar's test.

RESULTS

There were significant differences of mean ADC values (p < 0.001) and mean CRs (p = 0.003). With adopted threshold values, the specificity (85.7%) and accuracy (85.7%) of DWI were higher than those of STIR (specificity, 63.3%; p = 0.001 and accuracy, 66.1%; p = 0.001). In addition, the accuracy of combination of both indexes (94.6%; p = 0.04) could significantly improve as compared with DWI alone.

CONCLUSION

DWI is more useful for the differentiation of SCLC from NSCLC than STIR, and their combination can significantly improve the accuracy in this setting.

ADVANCES IN KNOWLEDGE

Pulmonary MRI, including DWI and STIR, had a potential of the suggestion of the possibility as SCLC.

Anesthetic effect of a combination of medetomidine-midazolam-butorphanol in cynomolgus monkeys (Macaca fascicularis)

The anesthetic effect of a combination of medetomidine, midazolam and butorphanol (Me-Mi-Bu) was evaluated in healthy cynomolgus monkeys. The Me-Mi-Bu combination was intramuscularly administered as follows: Dose 1, Me 0.015 mg/kg-Mi 0.1 mg/kg-Bu 0.15 mg/kg; Dose 2, Me 0.02 mg/kg-Mi 0.15 mg/kg-Bu 0.2 mg/kg; and Dose 3, Me 0.04 mg/kg-Mi 0.3 mg/kg-Bu 0.4 mg/kg. The combination rapidly induced immobilization, and lateral recumbency was reached within 15 min. The duration of anesthesia for each dose administered was follows: Dose 1, 47 ± 27 min; Dose 2, 113 ± 31 min; and Dose 3, 190 ± 24 min. The anesthetic effect of the combination was abolished by the α2-adrenoceptor antagonist atipamezole. No marked changes in the levels of hematologic or serum biochemical parameters were noted in cynomolgus monkeys administered the combination plus atipamezole. Taken together, these results suggest that the Me-Mi-Bu combination exhibits reversible anesthetic effect and may be useful for studies involving cynomolgus monkeys.

Dobutamine stress echocardiography for assessment of systolic function in dogs with experimentally induced mitral regurgitation

Background

Systolic dysfunction is associated with poor outcomes in dogs with myxomatous mitral valve disease. However, assessment of systolic variables by conventional echocardiographic methods is difficult in these dogs because of mitral regurgitation (MR).

Hypothesis

We hypothesized that assessment of systolic function by dobutamine stress may identify systolic dysfunction in dogs with MR, and that 2‐dimensional speckle‐tracking echocardiography (2D‐STE) could quantitatively evaluate myocardial function.

Animals

Anesthetized dogs with experimentally induced MR.

Methods

Dogs were examined for systolic myocardial deformations using 2D‐STE during dobutamine infusion before and 3 and 6 months after MR induction. We evaluated peak systolic rotation and rotation rate in each basal and apical view; peak systolic torsion and torsion rate were also calculated.

Results

Invasive peak positive first derivatives of left ventricular pressure (dp/dt) were significantly decreased in dogs 6 months after induction of MR compared with pre‐MR results. After 3 and 6 months of MR, dogs had diminished peak systolic torsion values and torsion rates in response to dobutamine infusion compared with pre‐MR results (3 months, P < .001 and P = .006; 6 months, P = .003 and P = .021). These results were significantly correlated with overall invasive dp/dt (r = 0.644, P < .001; r = 0.696, P < .001).

Conclusions and Clinical Importance

Decreased torsion during dobutamine infusion in dogs with MR may reflect latent systolic dysfunction. Dobutamine infusion, therefore, may be useful for the assessment of systolic function in dogs with MR.

140 THE EFFECTS OF INTERVALS OF MECHANICAL VIBRATION DURING IN VITRO CULTURE ON THE DEVELOPMENT OF BOVINE EMBRYO DERIVED FROM LOW-QUALITY OOCYTES

Mechanical vibration enhances the cytoplyasmic maturation of in vitro-matured (IVM) pig oocytes (Mizobe et al. 2010 J. Reprod. Dev. 56, 285–290), as well as the development of in vitro-cultured (IVC) bovine embryos (Fujita et al. 2010 Rakuno Gakuen University Graduation thesis,1–36). In this study, the effects of intervals of mechanical vibration during in vitro culture, after IVF, on the development of embryos derived from low-quality oocytes were examined. Cumulus-oocyte complexes (COC) were collected by aspiration of ovarian follicles (diameter = 2 to 6 mm) obtained from a local abattoir. In this experiment, only grade 3 oocytes (i.e. those with one layer or partially remaining cumulus cells and normal cytoplasm) were used. Groups of 20 COC were matured in 100-μL droplets of in vitro TCM-199 supplemented with 5% calf serum and 0.02 AU mL–1 of FSH at 38.5°C under an atmosphere of 5% CO2 in air for 20 h. Matured COC were inseminated with 5 × 106 sperms mL–1 for 18 h. After 18 h of gamete co-culture, the presumptive zygotes were cultured in CR1aa medium supplemented with 5% calf serum at 38.5°C under an atmosphere of 5% O2, 5% CO2, and 90% N2 for 9 days (fertilization = Day 0). Presumptive zygotes were cultured in vitro without mechanical vibration (control; n = 467) and with mechanical vibration for 5 s at 5 min (n = 180), 10 min (n = 180), 15 min (n = 180), and 60 min (n = 200) for 9 days. Embryo development was evaluated for cleavage and blastocyst rates, on Days 3 and 7 to 9 after IVF, respectively. The cleavage and blastocyst formation rates were analysed by the chi-squared test. Vibration at 15-min intervals increased (P < 0.05) cleavage rate compared to 5 min, 60 min, and control (control: 66.2 ± 22.1%; 5 min: 49.4 ± 10.2%; 10 min: 70.0 ± 7.7%; 15 min: 86.2 ± 6.6%; and 60 min: 64.0 ± 8.5%).The highest (P < 0.05) blastocyst rate among the experimental groups was found with 15-min intervals for vibration (control: 21.6 ± 9.2%; 5 min: 15.0 ± 5.3%; 10 min: 22.8 ± 1.8%; 60 min: 21.5 ± 5.0%). These results indicated that the cleavage and blastocyst formation rates of IVM-IVF-IVC bovine embryos derived from low-quality oocytes can be improved by physical stimulus during IVC. In addition, it was shown that 15-min intervals of mechanical vibration elicited the highest benefit for the development of embryos.

133 EFFECT OF PROGESTERONE SUPPLEMENTATION OF MATURATION MEDIUM ON THE DEVELOPMENT OF IN VITRO-MATURED-IN VITRO-FERTILIZED-IN VITRO-CULTURED BOVINE EMBRYOS

The objective of this study was to investigate whether progesterone (P4) supplementation to in vitro maturation (IVM) medium could affect the competence of bovine oocyte to develop into blastocysts in vitro. Cumulus–oocyte complexes (COC) were collected by aspiration of ovarian follicles (2 to 6 mm in diameter) obtained from a local abattoir. The COC were matured for 20 h in TCM-199 supplemented with 5% calf serum and 0.02 AU mL–1 FSH at 38.5° in an atmosphere of 5% CO2 in air. After 18 h of gamete co-culture (5 × 106 sperms mL–1), presumptive zygotes were cultured in CRlaa containing 5% calf serum at 38.5°C in an atmosphere of 5% CO2, 5% O2, and 90% N2 for 9 days (fertilization = Day 0). Progesterone was added to the IVM medium 10 h after the start of the culture (1 μg group = 1 μg mL–1 of P4; 5 μg group = 5 μg mL–1 of P4; control group = no P4). The maturation (MII) rates were investigated after 20 h of starting the IVM culture. After maturation, the COC were denuded mechanically, and a part of the oocytes were mounted on slides, fixed with aceto-alcohol (1 : 3) solution for 48 h, stained with aceto-orcein, and observed under a phase-contrast microscope to determine their nuclear status (1 μg group: n = 32; 5 μg group: n = 28; control group: n = 31). The remaining COC were used for IVF. The cleavage rates were investigated on day 2, and the blastocyst formation rates were investigated on Days 7 to 9, respectively (1 μg group: n = 264; 5 μg group: n = 274; control group: n = 277). The blastocysts from Day 7 were used for differential staining of the inner cell mass (ICM) and trophectoderm cells (TE). The total cell numbers, ICM, and TE in the blastocysts were counted (1 μg group: n = 28; 5 μg group: n = 24; control group: n = 24). The rates of MII, cleavage, and blastocyst formation were expressed and analysed by the chi-squared test. Each set of cell numbers (mean ± standard error) was analysed by the unpaired t-test. The MII rate in the control group (76.7%) was significantly lower (P < 0.05) than that in the 1 μg group (93.8%). The cleavage rate in the 1 μg group (85.6%) was significantly higher (P < 0.05) than those in the control group (74.7%) and 5 μg group (77.4%). Further, the blastocyst formation rate in the 1 μg group (47.7%) and 5 μg group (43.4%) were significantly higher (P < 0.05) than that in the control group (35.0%). The ICM numbers (mean ± s.e.) were 39.5 ± 13.8 to 36.2 ± 8.9, the TE numbers were 74.4 ± 22.4 to 66.2 ± 12.9, the total cell numbers of blastocysts were 110.6 ± 28.2 to 103.0 ± 13.8. There was no significant difference in cell numbers among the groups. These results indicate that the cleavage and blastocyst formation rates can be improved by the addition of 1 μg mL–1 of P4 to the maturation medium.

Effects of transport stress on serum alkaline phosphatase activity in beagle dogs

Here, to determine the effects of transport stress on blood parameters in dogs, we investigated the changes in hematologic and serum chemical parameters in healthy beagle dogs transported from Beijing, China, to Osaka, Japan, to obtain the background data. Only the activity of serum alkaline phosphatase increased clearly upon arrival, a change attributed to transport stress, but the activity gradually reduced afterward. No marked changes in levels of other blood parameters were noted. Our findings here suggest that alkaline phosphatase is a useful tool for studying transport stress.

D-histidine and L-histidine attenuate zinc-induced neuronal death in GT1-7 cells

Although zinc (Zn) is an essential trace element, excess Zn causes neuronal death following transient global ischemia and plays a central role in the pathogenesis of vascular-type dementia. In this study, we developed a rapid and convenient screening system for substances that prevent Zn-induced neurotoxicity by using GT1-7 cells (immortalized hypothalamic neurons), with the aim of identifying a treatment for vascular-type dementia. Among tested, we found a protective substance in the extract of round herring (Etrumeus teres), and determined its structure as l-histidine. Analysis of the structure-activity relationship by using histidine analogues revealed that both l-histidine and d-histidine exhibit the same neuroprotective activity. Furthermore, we investigated the molecular mechanisms underlying the protective effect of histidine on Zn-induced neurotoxicity using Zn imaging and gene expression analysis, and found that histidine protects against Zn-induced neurotoxicity not by inhibiting Zn chelation, thereby preventing increases in intracellular Zn(2+). Moreover, it is also suggested that endoplasmic reticulum (ER) stress and activity-regulated cytoskeleton associated protein (Arc) are implicated in Zn-induced degeneration of neurons.

Short communication: effects of serum obtained from dairy cows with low or high body condition score on in vitro embryo development

The objective of the study was to determine whether the serum obtained from animals differing in body condition score (BCS) affects in vitro embryo development. After in vitro fertilization, serum obtained from dairy cows of either low (L-BCS; 2.1 ± 0.14 on a scale of 1 to 5) or high BCS (H-BCS; 4.0 ± 0.0), or commercially available bovine serum (control) was added at 5% concentration to the in vitro culture medium. Use of serum obtained from H-BCS cows increased the cleavage rates compared with control serum at both 24 and 48 h after in vitro fertilization (78.3 vs. 71.9% and 79.9 vs. 75.1%, respectively), whereas use of serum obtained from L-BCS cows increased the blastocyst rate compared with control serum at 7d (23.8 vs. 19.1%), but this difference was not evident at 8 or 9 d after in vitro fertilization. As nonesterified fatty acid concentrations were highest in control serum, followed by serum from L-BCS and H-BCS cows (621, 559, and 272 μEq/L, respectively), a high concentration of nonesterified fatty acids might adversely affect the very early stages of embryo development, and its negative effects might be greater immediately after fertilization compared with developmental stages after morula formation. Our findings also indicate that factors promoting early stage embryo development do not necessarily promote blastocyst development. Serum obtained from animals under different physiological conditions may be used for in vitro embryo culture to study the effects of nutritional management of dairy cattle on embryo development.

Noninvasive clinical assessment of systolic torsional motions by two-dimensional speckle-tracking echocardiography in dogs with myxomatous mitral valve disease

BACKGROUND

Left ventricular torsional motion plays an important role for effective pump function. However, noninvasive clinical assessment of torsional deformations by two-dimensional speckle-tracking echocardiography (2D-STE) in dogs with myxomatous mitral valve disease (MMVD) has not been reported.

HYPOTHESIS

Left ventricular torsion is determined by the native orientation of the helical myocardial fibers, such that it might provide better assessment of myocardial function than conventional methods.

ANIMALS

Sixty-seven client-owned dogs with MMVD were classified into 3 classes based on the International Small Animal Cardiac Health Council classification and 16 weight- and age-matched healthy dogs.

METHODS

Dogs were examined for myocardial deformations by 2D-STE and were evaluated for peak systolic rotation and rotation rate at each basal and apical view. Dogs also were evaluated for peak systolic torsion and torsion rate.

RESULTS

Peak systolic torsion was higher in class II than in class I (P < .001) dogs. Peak systolic torsion was lower in class III than in class II (P = .001) dogs and controls (P = .003).

CONCLUSIONS AND CLINICAL IMPORTANCE

Torsional deformations assessed by 2D-STE differed among clinical classes of MMVD. Myocardial torsional deformations by 2D-STE may provide more detailed assessment of contractile function in dogs with MMVD.

Three-dimensional airway lumen volumetry: comparison with bronchial wall area and parenchymal densitometry in assessment of airway obstruction in pulmonary emphysema

OBJECTIVES

The purpose of this study was to compare three-dimensional airway lumen volumetry with bronchial wall area and parenchymal densitometry in the assessment of airway obstruction in pulmonary emphysema.

METHODS

56 patients, who were smokers, underwent CT examination and pulmonary function tests (PFTs). For quantitative assessments, the following parameters were computationally calculated: (1) percentage of voxels -950, -960 and -970 HU in the lung (%LAA(-950), %LAA(-960) and %LAA(-970), respectively); (2) percentage of partial bronchi luminal volumes per total luminal volumes (LV(main), main and distal bronchial volume/total luminal volume; LV(lobe), lobar and distal bronchial volume/total luminal volume); and (3) mean wall area percentages of segmental bronchi of the right apical and left apicoposterior segment (WA%(seg)) and of subsegmental bronchi (WA%(sub)) in the upper lobes. These parameters were correlated with PFTs and statistically compared between a chronic obstructive pulmonary disease (COPD) group [forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC)<70] and a non-COPD group.

RESULTS

FEV1, maximum mid-expiratory flow rate and forced expiratory flow at 25% vital capacity had significant correlation with LV(main) (r>0.53, p<0.0001), LV(lobe) (r>0.52, p<0.0001), WA%(seg) (|r|>0.29, p<0.05) and WA%(sub) (|r|>0.31, p<0.05). FEV1/FVC had significant correlation with all parameters (0.27<|r|<0.52, p<0.05). LV(main) and LV(lobe) and WA%(seg) and WA%(sub) were significantly different between the two groups (LV(main) and LV(lobe); p<0.0001, WA%(seg) and WA%(sub); p<0.05).

CONCLUSIONS

Bronchial luminal volumetric assessment better reflected the airflow limitation parameters.

ADVANCES IN KNOWLEDGE

Bronchial luminal volumetric assessment can potentially be used to gauge airflow limitation in pulmonary emphysema.

166 EFFECT OF INDIVIDUAL CULTURE SYSTEM ON IN VITRO DEVELOPMENT OF IN VITRO-MATURED - IN VITRO-FERTILIZED BOVINE EMBRYOS

An individual in vitro culture system for bovine embryo needs to be developed for the study of embryo developmental competence. The objective of this study was to examine the effect of individual culture systems on the development of in vitro-matured–in vitro-fertilized bovine embryos. Two individual culture systems were compared. Cumulus–oocyte complexes (COC) were collected by aspiration of ovarian follicles (diameter, 2 to 5 mm) obtained from a local abattoir. The COC were matured in TCM-199 supplemented with 5% calf serum and 0.02 AU mL–1 of FSH. Groups of 20 COC were incubated in 100-μL droplets of IVM media at 38.5°C under an atmosphere of 5% CO2 for 20 h. After 18 h of gamete co-culture (3 × 106 sperm mL–1), the presumptive zygotes were cultured in CR1aa medium supplemented with 5% calf serum at 38.5°C under an atmosphere of 5% CO2, 5% O2 and 90% N2 for 9 days (fertilization = Day 0). The presumptive zygotes were randomly assigned to 1 of the following 3 treatments: single culture (1 zygote was cultured in a 5-μL droplet), well-of-the-well (WOW; Sugimura et al. 2010 Biol. Reprod. 83, 970–978) culture (25 zygotes were cultured individually in each 125-μL droplet) and control culture (25 zygotes were cultured in a 125-μL droplet). Embryo development was evaluated for cleavage and blastocyst rates, on Day 2 and Day 7 to 9 after IVF, respectively. The rates of development up to the blastocyst stage and total cell number in the blastocysts, determined by an air-drying method, were investigated. The cleavage and blastocyst rates were analysed by the chi-square test and the total cell numbers were analysed by ANOVA. The cleavage rates were significantly higher in the control and WOW groups than in the single-culture group (P < 0.01) and the blastocyst rates were significantly lower in the single-culture group than in the control culture group (P < 0.05; Table 1). The total cell numbers (mean ± s.d.) of blastocysts did not significantly differ between the single culture (154.6 ± 21.8), control culture (155.2 ± 22.5) and WOW culture (159.8 ± 27.0) groups. These results indicate that although the blastocyst rate was lower in the single-culture system than in the WOW or group culture system, in vitro-matured–in vitro-fertilized bovine embryos can be cultured using the single-culture system. Moreover, the quality of blastocysts developed by the single-culture system is the same as that of blastocysts developed using the other 2 culture systems. Table 1.Effect of different culture methods for bovine embryo development

165 THE EFFECTS OF L-CARNITINE AND LINOLEIC ACID ALBUMIN SUPPLEMENTATION ON THE DEVELOPMENT AND CRYOSURVIVAL OF BOVINE IN VITRO-MATURED/IN VITRO-FERTILIZED EMBRYOS IN IN VITRO CULTURE MEDIUM

The objective of this study was to investigate the effects of the supplementation of a lipid metabolism inducer, L-carnitine (LC) and a membrane stabilizer, linoleic acid albumin (LAA), on the developmental competence and cryosurvival of bovine in vitro-matured/in vitro-fertilized embryos in in vitro culture medium. Cumulus–oocyte complexes collected from the ovaries of slaughtered cattle were matured for 20 h in TCM-199 supplemented with 5% calf serum (CS) and 0.02 AU mL–1 of FSH at 38.5°C in an atmosphere of 5% CO2 in air. After IVF (Day 0), presumptive zygotes were cultured in CRlaa containing 5% CS at 38.5°C in an atmosphere of 5% CO2, 5% O2 and 90% N2 for 9 days. The culture medium was supplemented with 0.6 mg mL–1 of LC (LC group; n = 180) or with 0.25 mg mL–1 of LAA (LAA group; n = 180) or with both LC and LAA (LC + LAA group; n = 180) or without LC and LAA (control; n = 178). The cleavage rates were recorded on Day 2 and the blastocyst formation rates were recorded on Day 7 to 9. Expanded blastocysts harvested on Day 7 and 8 (LAA group: n = 31; LC group: n = 29; LC + LAA group: n = 25; control group: n = 33) were used for freezing in modified PBS supplemented with 1.5 M ethylene glycol, 0.1 M sucrose and 20% CS. After thawing, they were cultured in TCM-199 supplemented with 20% FBS and 0.1 mM β-mercaptoethanol at 38.5°C under 5% CO2 in air for 72 h. The rates of re-expansion, hatching and formation of hatched blastocysts were determined at 24, 48 and 72 h after thawing, respectively. The rates of cleavage and blastocyst formation were expressed as mean ± s.e.m. and analysed by ANOVA. The post-thaw survival rates of frozen embryos were analysed by chi-square test. The cleavage rate in the control group (69.1 ± 2.5%) was significantly lower than that in the LAA (81.8 ± 3.8%) and LC + LAA groups (77.9 ± 1.4%) but did not differ from that in the LC group (73.8 ± 2.4%). The blastocyst formation rate in the control group (21.7 ± 2.8%) was significantly lower (P < 0.05) than those in the LAA and LC + LAA groups (33.5 ± 2.8% and 31.4 ± 2.4%, respectively), but it did not differ significantly from that of the LC group (32.1 ± 3.3%) despite a strong tendency (P = 0.06). There were no significant differences among the control, LC, LAA and the LC + LAA groups in post-thaw re-expansion rates (66.7, 75.9, 67.7 and 76.0%, respectively), hatching rates (48.5, 69.0, 58.1 and 64.0%, respectively) and rates of formation of hatched blastocysts (51.5, 62.1, 61.3 and 64.0%, respectively). These results indicate that the addition of LC and LAA to the medium for in vitro culture of in vitro-matured/in vitro-fertilized bovine embryos improved their ability to develop to the blastocyst stage; however, the effects on the freezing tolerance were not verified.

77 REPRODUCTIVE PERFORMANCE OF DAIRY COWS DIFFERING IN THE INTERVAL FROM CALVING TO THE FIRST OVULATION IN THE POSTPARTUM PERIOD

In recent years, reproductive performance of dairy cows has declined worldwide. The reproductive characteristics of dairy cows should be evaluated to improve their fertility. Dochi et al. (2010) had reported that dairy cows that exhibited early first ovulation gave a low milk yield, had an early recovery of body condition score (BCS) in the postpartum period and a shorter number of days open. The objective of this study was to evaluate the effect of BCS on the functional recovery of reproduction after the birth of the calves. In this study, lactating Holstein cows were placed in free-stall housing equipped with an automatic milking system. The data presented in this study were collected from 48 cows that had calved between December 2007 and October 2010 with an average parity of 3.4 (range 2–6). The reproductive performance and the BCS during the different intervals between calving and the first ovulation were analysed using ANOVA. The conception rate at the first service was 38.1%. The average milk yield (305 days) was 12 299 kg. The first ovulation and oestrus were determined by ultrasonography. The results of the different intervals to the first ovulation are presented in Table 1. The average interval from the start of days in milk (DIM) to the first ovulation, first oestrus and first service; the number of days open; the number of services per conception and the milk yield (kg day–1, by 90 DIM) were 37.4, 54.7 and 110.3 days; 168.2 days open; 2.5 times; and 42.1 kg day–1, respectively. The cows that exhibited early first ovulation (≤21 DIM) in the postpartum period had significantly shorter intervals between the start of DIM and the first oestrus (P < 0.01). However, the days to first service, the number of days open, the number of services per conception and the milk yield (kg day–1, by 90 DIM) did not differ significantly. The BCS in the peripartum period of different intervals to the first ovulation decreased from 3.1 to 2.4 by 150 DIM. This study showed that average BCS of preparturient 50–10 DIM is 3.0. Moreover, the average BCS of parturition is declining to 2.5 (parturition from 70 to 150 DIM). The cows became pregnant after an increase in the BCS (>150 DIM). In conclusion, these results suggest that the delay to the first ovulation in the postpartum period tended to have delayed the oestrus expression in the cows. Moreover, the low level of BCS in the peripartum period, regardless of the number of days of the first ovulation and the first oestrus, potentially influenced the prolongation in the number of days open. To improve the fertility of the cows, it is important to elucidate the factors affecting the fluctuations in the BCS during the peripartum period. Table 1.Reproductive performance of dairy cows differing in interval to postpartum first ovulation

P3-07-46: Accuracy of SPIO-Enhanced MR Imaging Alone for the Diagnosis of Sentinel Node Metastases in Patients with Breast Cancer

Background

Superparamagnetic iron oxide (SPIO)-enhanced MR imaging has been reported to be promising for the detection of metastases in sentinel nodes localized by CT lymphography in patients with breast cancer (Motomura, Ann Surg Oncol 2011). The current SPIO technique involves imaging before and after contrast administration. This study evaluated the accuracy of SPIO-enhanced MR imaging alone without unenhanced imaging.

Methods: This study included 120 patients with breast cancer demonstrating clinically negative nodes. Sentinel nodes were identified by CT lymphography, and MR imaging of the axilla before and 18–24 hr after interstitial administration of SPIO was performed. A node was considered non-metastatic if it showed a homogenous low signal intensity and metastatic if there was an absence of low signal intensity either in the entire node or in a focal area on SPIO-enhanced MR imaging. The diagnostic accuracy of the SPIO-enhanced imaging alone was compared with that of combined unenhanced and SPIO-enhanced imaging.

Results: The mean number of sentinel nodes identified by CT lymphography was 1.2 (range 1–3). Pathologic evaluation demonstrated that 28 (23.3%) of 120 patients showed metastasis to at least one node. One false negative result was added when the evaluation was based solely on SPIO-enhanced MR imaging. Consequently, the sensitivity decreased from 84.0% to 80.0% and the accuracy decreased from 89.2% to 88.3%, respectively, in the SPIO-enhanced MR imaging alone. However, the differences in sensitivity and accuracy between SPIO-enhanced MR imaging alone and the combined unenhanced and SPIO-enhanced imaging were not significant (McNemar's test; p=1.0). The specificity of enhanced imaging alone and that of combined unenhanced and SPIO-enhanced imaging were both 90.5%.

Conclusions: A single MR imaging examination performed after SPIO administration can be used for accurate diagnosis of sentinel node metastases, and thus reduce the time and cost of imaging.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-07-46.

Integration of Multilayers in Er-Doped Porous Silicon Structures and Advances in 1.5 μm Optoelectronic Devices

Infrared photoluminescence (PL) and electroluminescence (EL) from erbium-doped porous silicon (PSi) structures are studied. The PL and EL from the Er-doped PSi structures and the absence of silicon band edge recombination, point defect, and dislocation luminescence bands suggest that the Er-complex centers are the most efficient recombination sites. PSi multilayers with very high reflectivity (R ≥ 90%) in the 1.5 gim range have been incorporated in the structures resulting in a PL enhancement of over 100%. Stable and intense EL is obtained from the Er-doped structures. The EL spectrum is similar to that of the PL, but shifted towards higher energy. The unexpected shift in emission opens up the possibility for erbium related luminescence to encompass a larger part of the optimal wavelength window for fiber optic communications.

Zinc, copper, and carnosine attenuate neurotoxicity of prion fragment PrP106-126

Prion diseases are progressive neurodegenerative diseases that are associated with the conversion of normal cellular prion protein (PrP(C)) to abnormal pathogenic prion protein (PrP(SC)) by conformational changes. Prion protein is a metal-binding protein that is suggested to be involved in metal homeostasis. We investigated here the effects of trace elements on the conformational changes and neurotoxicity of synthetic prion peptide (PrP106-126). PrP106-126 exhibited the formation of β-sheet structures and enhanced neurotoxicity during the aging process. The co-existence of Zn(2+) or Cu(2+) during aging inhibited β-sheet formation by PrP106-126 and attenuated its neurotoxicity on primary cultured rat hippocampal neurons. Although PrP106-126 formed amyloid-like fibrils as observed by atomic force microscopy, the height of the fibers was decreased in the presence of Zn(2+) or Cu(2+). Carnosine (β-alanyl histidine) significantly inhibited both the β-sheet formation and the neurotoxicity of PrP106-126. Our results suggested that Zn(2+) and Cu(2+) might be involved in the pathogenesis of prion diseases. It is also possible that carnosine might become a candidate for therapeutic treatments for prion diseases.

Nonlinear Electrical Functions of Porous Silicon Light-Emitting Diodes

Some nonlinear electrical characteristics in electroluminescent porous silicon (PS) diodes with a relatively thin PS layer (0.5–5 μm thick) are described. The experimental PS diodes were composed of a semitransparent Au film, a PS layer, p- or n-type Si substrate, and an ohmic back contact. The PS layers were prepared by anodizing Si wafers in an ethanoic HF solution. In some cases, the PS layers were treated by rapid thermal oxidization (RTO) process. When the bias voltage is applied, the PS diodes show the electrical behavior like the metal-insulator-semiconductor (MIS) diodes. The negative-resistance characteristics and memory effect are also observed. These results indicate that the quantum-structured nature of the PS layer appears not only in the optical properties but also in the electrical properties.

221 EFFECT OF STAGE OF CORPUS LUTEUM DEVELOPMENT ON THE IN VITRO PRODUCTION OF BOVINE EMBRYOS

The objective of this study was to investigate the effect of stage of corpus luteum (CL) development on the in vitro production of bovine embryos. Ovaries were classified according to the expected day of the oestrous cycle based on the morphology of the ovaries. Ovaries with a corpus hemorrhagicum and the remnant of the follicular lumen filled with blood were considered the early luteal stage (Days 2 to 4; Day 0 = day of ovulation, n = 46). Ovaries with a large mass of orange tissue in the CL were classified as the midluteal stage (Days 7 to 10, n = 42). Cumulus–oocyte complexes (COC) were collected by aspiration of 2- to 6-mm follicles. The COC were classified into the following grades: COC with >3 compact layers of cumulus cells and evenly granulated cytoplasm were classified into Grade 1; COC with >3 layers cumulus cells and evenly granulated cytoplasm were classified into Grade 2; COC with partially remaining cumulus cells and abnormal cytoplasm were classified into Grade 3; COC without cumulus cells or those with expanded cumulus cells were classified into Grades 4 and 5, respectively. Grades 1 and 2 COC were in vitro matured for 20 h in TCM-199 supplemented with 5% calf serum and 0.02 mg mL–1 of FSH at 38.5°C under an atmosphere of 5% CO2 in air. Matured COC were inseminated with 5 × 106 sperm for 18 h. Presumptive zygotes were cultured in CR1aa medium supplemented with 5% calf serum at 38.5°C under an atmosphere of 5% O2, 5% CO2, and 90% N2 for 9 days (fertilization = Day 0). The mean number of COC and the proportion of COC classified as Grades 1 and 2 were analysed by ANOVA. Cleavage rates on Day 3 and blastocyst rates on Days 7 to 9 were analysed by a chi-square test. The mean number of recovered oocytes in the early luteal stage (18.7 ± 9.5) was significantly higher (P < 0.05) than the number in the midluteal stage (12.2 ± 5.7). The proportion of Grades 1 and 2 oocytes in the early luteal stage [66.7% (531/789)] was significantly higher (P < 0.01) than that in the midluteal stage [51.6% (252/484)]. The cleavage and blastocyst rates in the early luteal stage [60.9% (181/297) and 32.7% (97/297), respectively] were significantly higher (P < 0.05) than those in the midluteal stage [50.7% (76/150) and 20.7% (31/150) respectively].The present study suggests that the stage of development of the CL in bovine ovaries influences the number of recovered oocytes per ovary and the development of in vitro production of bovine embryos.

23 EFFECTS OF THE NUMBER OF SERVICES FERTILITY IN DAIRY COWS

In recent years, reproductive performance of dairy cows has been declining worldwide, especially among cows of high genetic merit for milk production. The cause of the low fertility may considerably vary across countries and is probably multifactorial. This problem remains unsolved. Further, the first-service conception rate of dairy cows has remarkably decreased worldwide. The number of services required for conception has increased due to the low fertility in dairy cows. However, there are few reports about the relationship between conception rates and the number of services in the current dairy cows. The objective of this study was to investigate whether the number of services affects the conception rates of dairy cows. Data concerning the conception rates was obtained for 8386 Holstein cows from 40 commercial dairy herds in eastern Hokkaido, Japan, from 2006 to 2009. The diagnosis of pregnancy was confirmed by rectal palpation between 30 and 45 days after insemination. The average interval between calving and the first-service was 87.3 days. The average milk yield was 8500 kg. Number of conducting services was from the first to the seventh service. The conception rate was analysed using chi-square test. The results are presented in Table1. The conception rate from the first to the seventh service was 40.2 to 54.0%. The conception rate at the first service was significantly low (40.2%); however, the conception rates did not significantly differ after the second-service. A similar tendency was observed during each year. Moreover, the total percentage of conceptions from the first to the third service was 83.8%. The average number of services per conception was 2.2. The results of this study indicate that the first service yielded the lowest conception rates. The conception rates after the second service did not significantly differ. Moreover, ∼84% of the dairy cows became pregnant between the first service and the third service. However, this result shows that ∼16% of the dairy cows in the herds were repeat breeding. In order to improve fertility, it is necessary to study the factors that affect the first-service conception rates of dairy cows. Moreover, to improve the conception rate of dairy cows, it is important to elucidate the cause of these problems. Table 1.The number and percentage of dairy cows conceiving at each of the services for consecutive services