Volatile and nonvolatile selective switching of a photo-assisted initialized atomic switch

A photo-assisted atomic switch, which has a photoconductive molecular layer in a gap of about 20 nm between an Ag2S electrode and a Pt electrode, is set to a conventional gap-type atomic switch operation mode by light irradiation with the application of a small bias that precipitates Ag atoms from an Ag2S electrode. After this initialization, the switch operates only with application of a bias. In this study, we also found that after the set-operation a photo-assisted initialized atomic switch shows different switching modes depending on the bias range, i.e., volatile switching when the applied bias is smaller than the threshold bias, and nonvolatile switching when the applied bias is larger than the threshold bias. These characteristics can be useful in reconfiguring a circuit such as in neural computing systems.

Impact of lithium-ion ordering on surface electronic states of Li(x)CoO2

Li(x)CoO(2) exhibits intriguing electronic properties due to a strong electron correlation and complex interplay between Co and Li ions. However, fundamental understanding of the nanoscale distribution of Li ions and its effect on the electronic properties remains unclear. We use scanning tunneling microscopy and density functional theory to elucidate the degree of Li(x)CoO(2) surface electronic state modification that can be achieved by Li ordering. The surface Li ions are highly mobile and preferentially form a (1 × 1) hexagonal lattice, whereas the surface CoO(2) layer shows metallic and insulating phases, indicating the coexistence of ordered and disordered Li ions in the subsurface layer. These results provide evidence of novel electronic properties produced by spatially inhomogeneous Li-ordering patterns.

Evaluation of Parkinson disease and Alzheimer disease with the use of neuromelanin MR imaging and (123)I-metaiodobenzylguanidine scintigraphy

BACKGROUND AND PURPOSE

Progressive changes in the substantia nigra pars compacta and locus ceruleus of patients with Parkinson disease and Alzheimer disease visualized by neuromelanin MRI and cardiac postganglionic sympathetic nerve function on (123)I-metaiodobenzylguanidine scintigraphy have not been fully evaluated. We compared the diagnostic value of these modalities among patients with early Parkinson disease, late Parkinson disease, and Alzheimer disease.

MATERIALS AND METHODS

We compared contrast ratios of signal intensity in medial and lateral regions of the substantia nigra pars compacta and locus ceruleus with those of the tegmentum of the midbrain and the pons, respectively, by use of neuromelanin MRI in patients with early Parkinson disease (n = 13), late Parkinson disease (n = 31), Alzheimer disease (n = 6), and age-matched healthy control subjects (n = 20). We calculated heart-to-mediastinum ratios on (123)I-metaiodobenzylguanidine scintigrams after setting regions of interest on the left cardiac ventricle and upper mediastinum.

RESULTS

The signal intensity of the lateral substantia nigra pars compacta on neuromelanin MRI was significantly reduced in early and late Parkinson disease, and that of the medial substantia nigra pars compacta was gradually and stage-dependently reduced in Parkinson disease. The signal intensity of the locus ceruleus was obviously reduced in late Parkinson disease. Signal reduction was not significant in the substantia nigra pars compacta and locus ceruleus of patients with Alzheimer disease. The heart-to-mediastinum ratio on (123)I-metaiodobenzylguanidine scintigrams was stage-dependently reduced in Parkinson disease and normal in Alzheimer disease. The signal intensity ratios in substantia nigra pars compacta and locus ceruleus on neuromelanin MRI positively correlated with the heart-to-mediastinum ratio on (123)I-metaiodobenzylguanidine scintigrams.

CONCLUSIONS

Both neuromelanin MRI and (123)I-metaiodobenzylguanidine scintigraphy can help to evaluate disease progression in Parkinson disease and are useful for differentiating Parkinson disease from Alzheimer disease.

Parenchymal hypointense foci associated with developmental venous anomalies: evaluation by phase-sensitive MR Imaging at 3T

BACKGROUND AND PURPOSE

The risk of hemorrhage in the context of developmental venous anomaly is considered to be very low, but it has never been evaluated by susceptibility-weighted MR imaging at 3T. The goal of the present study was to evaluate the prevalence of hypointense foci (ie, microhemorrhage or cavernous malformation) associated with DVA on phase-sensitive MR imaging, on the basis of principles similar to those of susceptibility-weighted MR imaging, and to evaluate the relationship between the hypointense foci and several factors, such as white matter hyperintense lesions adjacent to DVA on T2-weighted imaging, DVA morphology, and clinical symptoms.

MATERIALS AND METHODS

This study retrospectively evaluated 61 lesions in 59 consecutive patients with DVA who underwent MR imaging including phase-sensitive MR imaging. Two neuroradiologists independently assessed for the presence of hypointense foci and other factors such as DVA location, depth, size, direction of draining vein on phase-sensitive MR imaging, and white matter hyperintense lesion on T2-weighted imaging. Clinical symptoms were also assessed.

RESULTS

Hypointense foci were observed in 62.3% (38/61) of lesions. White matter hyperintense lesion was more frequently observed in patients with hypointense foci (26/38) than in patients without hypointense foci (7/23) (P < .01). There was no significant association between hypointense foci and other factors.

CONCLUSIONS

Our results support the hypothesis that microhemorrhage or cavernous malformation can be related to venous congestion caused by abnormal venous drainage. We conclude that phase-sensitive MR imagingis useful for the detection of microhemorrhage or cavernous malformation in patients with DVA, especially when associated with white matter hyperintense lesion.

Petroacetylene, a new polyacetylene from the marine sponge Petrosiasolida that inhibits blastulation of starfish embryos

A new C30 linear polyacetylene compound designated petroacetylene (1) has been isolated from the marine sponge Petrosia solida Hoshino 1981, collected off the coast of Amami-Oshima, Kagoshima Prefecture, Japan. The structure was elucidated on the basis of spectroscopic data and chemical means. Petroacetylene (1) inhibited blastulation of starfish embryos at a concentration of 3.1 μg mL(- 1) or greater.

Role of Occlusion in Masseter Muscle Acetylcholine Receptor Clustering

Nicotinic acetylcholine receptor (nAChR) clustering is a key event in the synaptogenesis of the neuromuscular junction (NMJ) for the efficient transmission of neural signals from motor neurons to skeletal muscle. The microphthalmic mouse ( mi/mi) with a mutation in the mitf gene cannot perform occlusion, because its teeth do not erupt. The present study attempted to elucidate the contribution of occlusion to the clustering of nAChR in the NMJ of the masseter, with mi/mi as a model system. In mice at 1 week of age, no significant change in the fragmentation or volume of the nAChR cluster was observed in either the masseter or gastrocnemius between breast-fed +/+ and mi/mi. In mice at 4 and 12 weeks of age, after the occlusion emerged in the +/+, excessive fragmentation and volume decline in the nAChR cluster were observed in the masseter of mi/mi fed a powdered diet compared with +/+ fed a pellet or powdered diet, whereas, in the gastrocnemius, no such differences were observed between the 2 strains. These results indicate abnormal formation of the nAChR cluster in the NMJ of the masseter of mi/mi, suggesting that occlusion is essential for the normal progress of nAChR clustering in the NMJ of the masseter.

Transient decrease in serum potassium level during ischemic attack of acute coronary syndrome: paradoxical contribution of plasma glucose level and glycohemoglobin

Background

Although a decrease in serum potassium level has been suggested to be a fairly common observation in acute coronary syndrome (ACS), there have so far been no definitive reports directly demonstrating the transient potassium decrease (the potassium dip) during ischemic attack of ACS compared to stable phase in individual patients. To understand the pathophysiological significance of the potassium dip, we examined the changes in serum potassium level throughout ischemic attack and evaluated the clinical factors affecting it.

Methods

The degree of the potassium dip during ischemic attack (as indicated by ΔK, ΔK = K at discharge − K on admission) was examined in 311 consecutive patients with ACS who required urgent hospitalization in our institution.

Results

Serum potassium level during ischemic attack was significantly decreased compared to that during stable phase (P < 0.001). Multiple regression analysis revealed that plasma glucose level during attack was the sole factor which was positively correlated with ΔK (P < 0.01), while HbA1c level was negatively correlated (P < 0.05). The medication profiles and renal function had no impact on ΔK. A longer hospitalization period, higher incidence of myocardial infarction and higher peak creatine kinase level were observed in patients with a larger ΔK.

Conclusions

We have clearly demonstrated that there is a transient decrease in serum potassium level during ischemic attack of ACS compared to stable phase. The degree of the potassium dip was tightly correlated with glucose level, which overwhelmed the diabetic condition, and it also indicates the disease severity. The present study therefore promotes awareness of the significance of monitoring potassium level in parallel with glucose level in patients with ACS.

Biphasic action of aldosterone on Akt signaling in cardiomyocytes

Both aldosterone and Akt signaling play pivotal roles in the pathogenesis of heart failure. However, little is known about the correlation between them. We herein investigated whether aldosterone interacts with Akt signaling in a coordinated manner in cardiomyocytes. Neonatal rat cardiomyocytes were stimulated with aldosterone for either a short (10-min) or long (24-h) time. The phosphorylation of Akt and its downstream effector, GSK3β, were transiently increased after short-term stimulation, which was blocked by either PI3K or Na(+)/H(+) exchanger inhibitors, but not by the mineralocorticoid receptor antagonist, eplerenone. Long-term stimulation also significantly increased Akt-GSK3β phosphorylation and this effect was reduced by eplerenone. Thus, these results suggest that aldosterone activates Akt signaling via a biphasic reaction that occurs through different cascades. To understand the significance of the rapid action of aldosterone, cardiomyocytes were exposed to hydrogen peroxide for from 10 to 60 min. A short-term aldosterone stimulation (for up to 30 min) significantly protected cardiomyocytes from oxidative stress-induced cellular damage. Eplerenone did not abrogate this beneficial effect, while a PI3K inhibitor did. Therefore, during the early phase, aldosterone has favorable effects on cardiomyocytes, partly by acute activation of a mineralocorticoid receptor-independent cascade through the Na(+)/H(+) exchanger, PI3K, and Akt. In contrast, its persistent activity produces pathological effects partly by chronic Akt activation in a mineralocorticoid receptor-dependent manner.

Lifestyle and colorectal cancer: A case-control study

A case-control study has been conducted to investigate the relationship between lifestyle and risk of colorectal cancer. Cases are one hundred patients diagnosed with colon and rectal cancer in Tokai University Hospital between 1986 and 1994. Three controls per case were individually matched by age, sex, local areas and date of health checkups at the Automated Multi-phasic Health Testing and Services (AMHTS ) Center of the hospital. The results were analyzed by multi-factorial logistic regression models. Positive history of maternal cancer, large consumption of alcohol, frequent consumption of potato products and white-collar job were predominant risk factors while frequent intake of seaweed was a protective factor. Frequent intakes of dairy foods and lack of exercise showed no significant tendency to increase risk of colorectal cancer. Smoking habits, intakes of meat and egg were shown not to be related to this disease. These findings suggest that family history of cancer and dietary factors play a key role in causation and prevention of colorectal cancer.

Health-related quality of life does not predict mortality in idiopathic pulmonary fibrosis

BACKGROUND

Although health-related quality of life (HRQL) has recently been considered to be an important outcome in clinical trials of idiopathic pulmonary fibrosis (IPF), its relationship with survival is unknown.

OBJECTIVE

To determine the prognostic significance of HRQL scores in IPF assessed with the SGRQ.

DESIGN

Eighty-seven consecutive patients with IPF, who had undergone evaluations and completed the St. George's Respiratory Questionnaire (SGRQ) at diagnosis were included in this study, as is the general practice. Cox proportional hazards analyses were performed to examine the relationship between HRQL scores and survival.

RESULTS

The mean observation period was 44.2 +/- 29.6 mo, in the course of which 54 patients (62.0%) died. Univariate analysis revealed that the activity scores in the SGRQ(HR: 1.016, 95% CI: 1.004-1.029, P = 0.01) were significantly predictive of survival, although the symptoms, impacts, and total scores were not significantly related to mortality from all causes. However, multivariate analysis revealed that only the forced vital capacity percent predicted was a significant predictor of survival, and that the activity score in the SGRQwas not significantly related to mortality.

CONCLUSIONS

There was no significant relationship between HRQL evaluated with the SGRQ and the subsequent mortality in IPF. The present negative result might suggest that HRQL is measuring an aspect other than one from physiological and functional impairment or disability.

The absence of somatotroph proliferation during continuous stress is a result of the lack of extracellular signal-regulated kinase 1/2 activation

The integrity of homeostasis can be affected by chronic stress, and hyposomatotropism is evident in chronic stress-associated illnesses. In the present study, we demonstrated that a continuous stress (CS) severely affected somatotrophs among hormone-secreting cells in the anterior lobe (AL) of the pituitary by using a rat CS model. Among AL cells, the proliferation of somatotrophs was almost entirely suppressed in rats that had 3-5 days of CS (5dCS), although other hormone-secreting cells continued to proliferate. The cell size of somatotrophs was reduced at 5dCS (P<0.01), the number of secretory granules was increased at 3dCS (P<0.01) and serum growth hormone (GH) was on declining trend during 1 to 5dCS, suggesting that GH release was inhibited. GH-releasing hormone (GHRH) mRNA level in the arcuate nucleus was transiently decreased, whereas its receptor expression in the AL was significantly increased in CS rats. When 5dCS rats were injected with GHRH, transient GH secretion was observed, whereas proliferation of somatotrophs did not occur. The GHRH administration failed to stimulate extracellular signal-regulated kinase (ERK) 1/2 phosphorylation and the nuclear translocation of ERK in somatotrophs. These results suggest that somatotrophs of 5dCS rats expressed sufficient GHRH receptor, which could transfer a signal for GH release. However, the GHRH-induced proliferation signal was blocked somewhere between the receptor and ERK1/2. Because significant increase of corticosterone in the initial stage (the 1-3dCS) was observed in this model, the corticosterone may affect the signalling. Although the mechanism underlying the blockage of the proliferation signal in somatotrophs under CS remains unclear, these somatotrophic disorder, suggesting that the present animal model may be useful for understanding the molecular mechanisms of chronic stress-associated illnesses.

Cardiac tamponade as an independent condition affecting the relationship between the plasma B-type natriuretic peptide levels and cardiac function

Plasma B-type natriuretic peptide (BNP) is finely regulated by the cardiac function and several extracardiac factors. Therefore, the relationship between the plasma BNP levels and the severity of heart failure sometimes seems inconsistent. The purpose of the present study was to investigate the plasma BNP levels in patients with cardiac tamponade and their changes after pericardial drainage. This study included 14 patients with cardiac tamponade who underwent pericardiocentesis. The cardiac tamponade was due to malignant diseases in 13 patients and uremia in 1 patient. The plasma BNP levels were measured before and 24-48 h after drainage. Although the patients reported severe symptoms of heart failure, their plasma BNP levels were only 71.2 ± 11.1 pg/ml before drainage. After appropriate drainage, the plasma BNP levels increased to 186.0 ± 22.5 pg/ml, which was significantly higher than that before drainage (P = 0.0002). In patients with cardiac tamponade, the plasma BNP levels were low, probably because of impaired ventricular stretching, and the levels significantly increased in response to the primary condition after drainage. This study demonstrates an additional condition that affects the relationship between the plasma BNP levels and cardiac function. If inconsistency is seen in the relationship between the plasma BNP levels and clinical signs of heart failure, the presence of cardiac tamponade should therefore be considered.

Subarachnoid hyperattenuation on flat panel detector-based conebeam CT immediately after uneventful coil embolization of unruptured intracranial aneurysms

BACKGROUND AND PURPOSE

Flat panel detector-based CBCT can provide CT-like images of the brain without transferring patients from the angiography suite to a conventional CT facility. Conventional brain CT after uneventful endovascular treatment sometimes shows focal subarachnoid hyperattenuation with contrast leakage, mimicking SAH. Differentiating this finding from SAH is important for immediate postprocedural medical management. We investigated CBCT for detecting subarachnoid hyperattenuation immediately after coil embolization of unruptured cerebral aneurysms.

MATERIALS AND METHODS

Thirty-six patients with unruptured cerebral aneurysms undergoing CBCT immediately after uncomplicated coil embolization were included. The relationship between the presence of subarachnoid hyperattenuation and total volume of contrast medium injected, aneurysm size and location, and balloon and stent assistance during embolization was investigated. Statistical analyses were performed with the χ(2) test (P < .05).

RESULTS

Nine of the 36 patients (25.0%) showed focal subarachnoid hyperattenuation within the relevant parent artery territory harboring the aneurysm. Subarachnoid hyperattenuation locations included the ipsilateral superior frontal sulcus (n = 5), the bilateral superior frontal sulcus (n = 1), and the ipsilateral superior frontal and precentral sulci (n = 3). Statistically significant differences were observed between the presence of a subarachnoid hyperattenuation and the total volume of contrast medium injected (P < .001) and aneurysm size (P < .05).

CONCLUSIONS

Subarachnoid hyperattenuation can be detected by CBCT immediately after coil embolization for unruptured aneurysms. The increased amounts of contrast medium to be given before CBCT and the specific location of the hyperattenuation may help differentiate benign subarachnoid contrast leakage from SAH.

Successful closure of intractable tracheoesophageal fistula using a combination of a modified silicon stent and metallic stents

Although surgery is the usual management strategy for acquired benign tracheoesophageal fistula, sometimes this approach is contraindicated or the patient declines surgical management. In this report, we describe a case of a patient with tracheoesophageal fistula at the level of the carina due to bronchial arterial infusion chemotherapy. Closure could not be achieved in response to multiple treatment strategies, including airway stenting, esophageal stenting, occlusion with microcoils, or cyanoacrylate glue. We subsequently achieved closure of this fistula through the combination of a modified silicon stent and metallic stents.

Self-assembled Nano-layering at the Adhesive Interface

According to the ‘Adhesion–Decalcification’ concept, specific functional monomers within dental adhesives can ionically interact with hydroxyapatite (HAp). Such ionic bonding has been demonstrated for 10-methacryloyloxydecyl dihydrogen phosphate (MDP) to manifest in the form of self-assembled ‘nano-layering’. However, it remained to be explored if such nano-layering also occurs on tooth tissue when commercial MDP-containing adhesives (Clearfil SE Bond, Kuraray; Scotchbond Universal, 3M ESPE) were applied following common clinical application protocols. We therefore characterized adhesive-dentin interfaces chemically, using x-ray diffraction (XRD) and energy-dispersive x-ray spectroscopy (EDS), and ultrastructurally, using (scanning) transmission electron microscopy (TEM/STEM). Both adhesives revealed nano-layering at the adhesive interface, not only within the hybrid layer but also, particularly for Clearfil SE Bond (Kuraray), extending into the adhesive layer. Since such self-assembled nano-layering of two 10-MDP molecules, joined by stable MDP-Ca salt formation, must make the adhesive interface more resistant to biodegradation, it may well explain the documented favorable clinical longevity of bonds produced by 10-MDP-based adhesives.

43 EFFECT OF VITRIFICATION AT GERMINAL VESICLE STAGE ON THE MITOCHONDRIAL AND CYTOSKELETAL INTEGRITY IN BOVINE OOCYTES

In the previous report, we demonstrated that bovine germinal vesicle (GV) stage oocytes vitrified using a nylon mesh holder showed an in vitro maturation rate to the metaphase II (MII) stage similar to that of fresh ones. However, cleavage and developmental rates of vitrified oocytes were low. Because mitochondria and the cytoskeleton are thought to have a central role in energy supply and cellular division in mammalian embryogenesis, it seems possible that alternation in their function in vitrified GV oocytes may contribute to subsequent lower cleavage and developmental rates. The oxygen consumption rate reflects the mitochondrial activity and its measurement may be an effective way for non-invasive evaluation of oocyte quality. In this study, to ascertain that altered mitochondrial functions and cytoskeleton may contribute to reduce the quality of oocytes after vitrification, we evaluated the distribution of active mitochondria and the cytoskeleton in vitrified oocytes. We also examined the relationship between oxygen consumption rate and the distribution of active mitochondria in vitrified oocytes. Bovine GV oocytes connected with cumulus cells were exposed to the cryoprotectant (EFS40) in a stepwise way and transferred onto a nylon mesh holder, followed by plunging them directly into liquid nitrogen. After warming, vitrified oocytes were allowed in vitro maturation. After denuding, matured oocytes were stained with a mitochondria-specific probe, rhodamine-123 and then oxygen consumption rate using an embryo respirometer (HV-403; Research Institute for Functional Peptides, Yamagata, Japan) was measured in each oocyte. According to morphological distribution of mitochondria, oocytes were classified as follows: type 1, uniform distribution; type 2, spotted distribution; and type 3, a weak fluorescence. The oxygen consumption rate of the fresh oocytes at the MII stage was significantly (P < 0.05) higher than that of vitrified oocytes (5.24 and 4 × 1015 mol–1 s–1, respectively), although there was no difference between the fresh and vitrified groups at the GV stage (5.02 and 5.06 × 1015 mol–1 s–1, respectively). The oxygen consumption rates of type 1 oocytes in fresh and vitrified groups at the MII stage tended to be higher than those of type 2 and 3 oocytes (type 1, 5.29 and 5.27; type 2, 4.99 and 4.52; type 3, 4.77 and 4.48 × 1015 mol–1 s–1, respectively). In addition, the percentage of type 1 oocytes in the fresh group was significantly (P < 0.05) higher than that in the vitrified group (59.4 and 34.3%, respectively). The matured oocytes also were stained with α-tubulin monoclonal antibody or F-phalloidin independently to examine the morphological status of microtubules or microfilament. The rates of oocytes with abnormal microtubules and microfilament in the vitrified group were 29.7 and 43.5%, respectively, showing higher rates compared with corresponding fresh oocytes (9.8%; P < 0.05 and 25.0%; P = 0.21, respectively). These results suggested that the reduction of quality and subsequent developmental competence in vitrified oocytes might be related to damages of mitochondria and cytoskeleton.

Contribution of extracardiac factors to the inconsistency between plasma B-type natriuretic peptide levels and the severity of pulmonary congestion on chest X-rays in the diagnosis of heart failure

OBJECTIVE

Chest X-rays and plasma B-type natriuretic peptide (BNP) levels are useful for diagnosing congestive heart failure. However, the relationship between plasma BNP levels and pulmonary congestion on chest X-rays often seems inconsistent. Extracardiac factors can directly alter plasma BNP levels, independent of cardiac function. In the present study, we examined the clinical factors that impact the diagnosis of heart failure by using chest X-rays and plasma BNP levels.

METHODS AND RESULTS

This study comprised 459 consecutive patients who were admitted to the cardiovascular division of our hospital for any reason and in whom chest X-rays and plasma BNP levels were measured within 12 hours after admission. The approximate BNP value associated with pulmonary congestion that was detectable by chest X-rays was 143 pg/mL, but this value was influenced by renal function, age, and body mass index (BMI). Furthermore, we examined the effect of these three extracardiac factors on plasma BNP levels in each stage of pulmonary congestion. We found that renal dysfunction and advanced age increased the plasma BNP levels, whereas a high BMI decreased the levels, and that the effect of BMI on plasma BNP levels was greater for severe heart failure.

CONCLUSION

Extracardiac factors should be considered when the relationship between the plasma BNP levels and the severity of pulmonary congestion on chest X-rays seems inconsistent. In particular, low levels of plasma BNP in patients with a high BMI should be carefully considered to avoid underestimating the degree of heart failure.

N-acetyl cysteine protects osteoblastic function from oxidative stress

We tested the protective potential of an antioxidant amino acid derivative, N-acetyl cysteine (NAC), in controlling oxidative stress against osteoblasts. Osteoblastic cells extracted from rat bone marrow were cultured. Oxidative stress was induced by adding 100 μM H₂O₂ into the culture media. Then, some H₂O₂-treated cultures were cotreated with 2.5 or 5 mM NAC. Addition of H₂O₂ decreased the number of cells to 50% of untreated cultures at days 2. Addition of 5 mM NAC into H₂O₂ cultures resulted in a dose-dependent increase in the number of cells, with the cell number being 50% greater than that in the 100 μM H₂O₂ culture. The gene expression levels of type I collagen, osteopontin, and osteocalcin were downregulated threefold by H₂O₂ on day 7. The H₂O₂-suppressed gene expression was fully recovered by NAC cotreatment. The mineralizing capability, assessed by Von Kossa staining on day 15, were approximately 1.8 times greater in the NAC + H₂O₂ cotreated group than in the culture with H₂O₂ alone. These NAC-mediated restorations were associated with an NAC dose-dependent increase of intracellular glutathione and a NAC dose-dependent decrease of intracellular reactive oxygen species. In conclusion, oxidative stress induced by H₂O₂ substantially impairs the proliferation, differentiation, and mineralization of osteoblasts. More importantly, the addition of NAC into the culture was found to restore these damages to a near normal level due to the improved redox balance, warranting further in vivo studies to test its therapeutic potential as a local antioxidative stress drug.

A case of lobular carcinoma in situ presenting as a solid mass

A patient presented with a 2 cm lump in the lower outer quadrant of the left breast. Mammogram and ultrasonography showed a solid mass with a microlobulated contour, partially irregular border and microcalcifications. MRI showed an irregular mass with early enhancement and high signal intensity, and the late-phase image demonstrated a partial washout pattern. These findings suggest that the tumour was a malignant invasive carcinoma. Non-invasive ductal carcinoma was diagnosed after a fine needle aspiration and core needle biopsy followed by a partial breast excision and sentinel lymph node (SLN) biopsy. A pathological examination of the lesion displayed characteristic small monomorphic cells, solid proliferation and massive distension within the lobular unit. The tumour was immunohistochemically negative for E-cadherin and pure lobular carcinoma in situ (LCIS) was diagnosed. Pure LCIS is very rare and there have been no previous reports of pure LCIS forming a solid mass.

Fundamental and Technological Aspects of Actinide Oxide Pyrochlores: Relevance For Immobilization Matrices

Polycrystalline pyrochlore oxides consisting of selected f elements (lanthanides and actinides) and Zr and Hf have been prepared and characterized. Characterization to date has been primarily by X-ray diffraction, both at room and at elevated temperatures. Initial studies concentrated on selected lanthanides and the Np, Pu and Am analogs (reported here) but have been extended to the other actinide elements through Cf. Data from these studies have been used to establish a systematic correlation regarding the fundamental materials science of these particular pyrochlores and structurally related fluorite-type dioxides. In addition to pursuing their materials science, we have addressed some potential technological applications for these materials. Some of the latter concern: (1) immobilization matrices; (2) materials for transmutation concepts; and (3) special nuclear fuel forms that can minimize the generation of nuclear wastes. For f elements that display both a III and IV oxidation state in oxide matrices, the synthetic path required for producing the desired pyrochlore oxide is dictated by their pseudo-oxidation potential the stability of the compound towards oxygen uptake. For the f elements that display an oxidationreduction cycle for pyrochlore-dioxide solid solution, X-ray diffraction can be used to identify the composition in the oxidation-reduction cycle, the oxygen stoichiometry and/or the composition. This paper concentrates on the Np, Pu and Am systems, and addresses the above aspects, the role of the crystal matrix in controlling the ceramic products as well as discussingsome custom-tailored materials.

Remote access laparoscopic (REAL) surgery: a novel approach for single-port surgery without a visible scar

INTRODUCTION

Single-port laparoscopic surgery usually uses the transumbilical approach. However, the transumbilical incision may be associated with a high frequency of wound-related complications, including trocar site hernia and infection. Therefore, we developed remote access laparoscopic (REAL) surgery, a new access technique for single-port surgery within the pubic hairline. This study reports on a technique developed at our institution and describes our preliminary results.

MATERIALS AND SURGICAL TECHNIQUE

Ten patients with cholecystolithiasis underwent REAL surgery. A single 2.5-cm transverse incision was made medially within the pubic hairline area, and a SILS Port was inserted. A 5-mm flexible endoscope and an articulating grasper or a long laparoscopic grasper were used. Dissection of the gallbladder was achieved with laparoscopic ultrasonic shears just as in the conventional laparoscopic cholecystectomy. All procedures were successfully performed without conversion to conventional laparoscopic technique. There were no postoperative complications, and outpatient evaluation showed a clean scar within the pubic hair area in all patients.

DISCUSSION

Our early experience shows that REAL surgery is feasible and safe. This novel access technique can preserve the native umbilicus and provides an invisible scar that is concealed within the pubic hair.

Impact of chronic kidney disease on the severity of initially diagnosed coronary artery disease and the patient prognosis in the Japanese population

This study evaluated the relationship between the severity of coronary artery disease (CAD) and traditional coronary risk factors, metabolic syndrome, and chronic kidney disease (CKD). Three hundred and forty-three patients (35-90 years of age) with initial diagnosis of CAD were separated into two groups: 165 patients with single-vessel coronary artery disease (SVD group) and 178 patients with multivessel coronary artery disease (MVD group). We compared the risk factors for CAD between the two groups. An adjusted multivariate analysis showed that only CKD was associated with MVD (odds ratio, 2.85; 95% confidence interval [CI], 1.76-4.63; P = 0.00002). Next, the relationship between the severity of CAD, CKD, and the incidence of subsequent major adverse cardiac event (MACE) was investigated in 338 patients during the patient follow-up. The risk of MACE was approximately threefold higher in the group with MVD and CKD stage of 3 or greater than in the group with SVD but without CKD stage of 3 or greater (adjusted hazard ratio, 3.40; 95% CI, 1.26-9.17; P = 0.016). A statistical analysis also suggested that having MVD and advanced CKD was a more powerful risk factor for MACE. The comparison of risk factors between patients with SVD and patients with MVD revealed that CKD was the most important risk factor for MVD. In addition, having MVD and advanced CKD together was a crucial risk factor for subsequent MACE. To reduce the progression of CAD and to improve the prognosis of patients with MVD, the renal status should therefore be carefully assessed during treatment for CAD.

Enhancement of adhesion strength and cellular stiffness of osteoblasts on mirror-polished titanium surface by UV-photofunctionalization

Ultraviolet (UV)-photofunctionalization of titanium substantially enhances the strength and quality of osseointegration by promoting osteogenic cellular attachment and proliferation. However, the mechanism underlying the initial interaction between the cells and the surface of the material remains to be elucidated, especially where the influence of surface roughness is excluded as a factor. The effect of UV-photofunctionalization on the adhesive strength and cellular stiffness of a single osteoblast and its association with the extent of cell spread, cytoskeletal development and focal adhesion assembly on a very smooth titanium surface was evaluated. Rat bone marrow-derived osteoblasts were cultured on UV-treated or untreated mirror-polished titanium disks. The mean critical shear force required to initiate detachment of a single osteoblast (n=10) was >2000nN on a UV-treated surface at 3h incubation, which was 17 times greater than that on an untreated surface. The mean total energy required to complete the detachment of osteoblasts (n=10) was consistently >60pJ on a UV-treated titanium surface after 24h culture, which was up to 42 times greater than that on an untreated surface. Cellular shear modulus, which represents cellular stiffness, was consistently greater on a UV-treated surface than on an untreated surface after 24h incubation (n=10). This strengthening of cell adhesion and cellular mechanical properties on UV-treated titanium was accompanied by enhanced cell spread and actin fiber development and increased levels of vinculin expression. These results indicate that UV-photofunctionalization substantially strengthens osteoblast retention on titanium bulk material with no topographical features, and that this is associated with enhancement of intracellular structural development during the cell adhesion process.

Non-syndromic Oligodontia with a Novel Mutation of PAX9

Agenesis of the permanent teeth is a congenital anomaly that is frequently seen in humans. Oligodontia is a severe type of tooth agenesis involving 6 or more congenitally missing teeth, excluding the third molars. Previous studies have indicated that mutations in the homeobox gene MSX1, paired domain transcription factor PAX9, and EDA are associated with non-syndromic oligodontia. This study reports a Japanese family (eight of 14 family members affected) with non-syndromic oligodontia who preferentially lacked molar teeth. In this family, a novel frameshift mutation (321_322insG) was identified in the paired domain of PAX9. The frameshift mutation caused altered amino acids in the paired domain and premature termination of translation by 26 amino acids. When transfected into COS-7 cells, the mRNA expression of 321_322insG PAX9 was comparable with that of wild-type PAX9. However, the mRNA of 321_322insG PAX9 was more unstable than that of wild-type PAX9. This mRNA instability caused a marked decrease in protein production, as evaluated by Western blot analysis and immunostaining. These findings suggest that the 321_322insG mutation causes insufficient function of PAX9 protein and haploinsufficiency as a genetic model of familial non-syndromic oligodontia with a PAX9 mutation.

N-acetyl cysteine protects TMJ chondrocytes from oxidative stress

Temporomandibular joint (TMJ) inflammation is closely associated with oxidative stress. This study tested the potential of N-acetyl cysteine (NAC), an anti-oxidant amino-acid derivative, in alleviating oxidative stress-related damage in TMJ chondrocytes. The inflammatory condition was simulated by the addition of hydrogen peroxide (H₂O₂) to TMJ-derived chondrocyte cultures. Exposure to H₂O₂ decreased the cell population by half within 2 days as a result of induced apoptosis and reduced proliferation. Gene expression of aggrecan and collagen II, as well as glycosaminoglycan production, were reduced by more than 70%. These compromised chondrocyte viability and function were fully restored by the addition of NAC to the cultures. NAC reduced the H₂O₂-elevated intracellular reactive oxygen species to the normal level and increased cellular glutathione reserves. These results indicate that NAC restores oxidative stress-induced cell death and severe functional impairment in TMJ chondrocytes, and warrant in vivo testing to explore its therapeutic potential as an anti-inflammatory agent.

OSCEs in Japanese postgraduate clinical training Hiroshima experience 2000-2009

BACKGROUND

Hiroshima University Hospital used the Objective Structured Clinical Examination (OSCE) as a formative and summative assessment tool to evaluate trainees' competence.

AIM

To reflect on Hiroshima University Hospital experience of OSCEs in postgraduate training in terms of OSCE structure and trainees' perception of the OSCE they attended.

METHODS

A total 27 OSCEs implemented in Hiroshima University Hospital from 2000 to 2009 were examined. The OSCE in postgraduate training, Hiroshima University Hospital, was influenced by many factors from organisational and pedagogical perspectives, and changed to meet social and curriculum needs. At each OSCE, all examinees were required to answer an anonymous questionnaire, which consisted of ten checklists, just after their experience of OSCE.

RESULTS

Five hundred and forty trainees who attended each OSCE were required to answer a questionnaire and 510 were returned (94.4%). In the comparison between formative and summative OSCEs, the number of trainees who answered "the OSCE is meaningful" in formative OSCE was significantly higher than that in summative OSCE (P < 0.001). In the comparison between before and after the 2006/2007 academic year, trainees who indicated that OSCEs were meaningful increased after 2006/2007 (P < 0.05), and trainees who felt they were evaluated appropriately by these OSCEs increased after 2006/2007 (P < 0.01).

CONCLUSION

Trainees viewed OSCEs positively and appreciated their effectiveness from a pedagogical perspective, and OSCE positively affected the trainees' approach to learning. A ten-year process of OSCE change has helped with educational reforms because of its adaptability. Flexible attitudes to change are necessary for stakeholders to achieve the desired reforms.

Identification and expression analysis of connexin-45 and connexin-60 as major connexins in porcine oocytes

During mammalian oogenesis, intercellular communication between oocytes and the surrounding follicle cells through gap junction channels is crucial for oocyte development and maturation. The channel properties of gap junctions may be affected by the composition or combination of connexins, the expression of which is regulated by gonadotropins and other factors. Thus, identification and expression analysis of connexin genes in oocytes and follicle cells will help us to better understand how oogenesis and folliculogenesis are regulated in a species-specific manner in mammals. We previously reported the spatiotemporal expression of multiple connexin genes in porcine follicle cells. Here, we searched for connexin genes specifically expressed in porcine oocytes that may be involved in the formation of gap junctions between oocytes and follicle cells. To achieve this, we constructed an oocyte-specific cDNA library to identify which connexin genes are expressed in these cells and found that gap junction protein, alpha 10, which encodes connexin-60, and a porcine ortholog of mouse gap junction protein, gamma 1 encoding connexin-45, are the major connexins expressed in porcine oocytes during folliculogenesis. Immunostaining and in situ hybridization of sectioned porcine ovaries confirmed oocyte expression of these genes at 3 different stages of ovary development. Furthermore, their gap junction channel activity was assessed using a heterologous cell system. However, gap junction protein, alpha 4, which encodes connexin-37 and is expressed in the oocytes of several other mammals, was undetectable. We demonstrate that there is diversity in the connexin genes expressed in mammalian oocytes, and hence in the gap junctions connecting oocytes and cumulus cells.

Genetically engineered mutant of the cyanobacterium Synechococcus PCC 7942 defective in nitrate transport

Nitrate-grown cells of Synechococcus PCC 7942 (Anacystis nidulans R2) contain a 45-kDa protein as a major protein in the cytoplasmic membrane but ammonium-grown cells lack it. A mutant (M45) was constructed by inactivating the gene encoding the 45-kDa protein. M45 did not grow under low concentrations of nitrate but high concentrations of nitrate could support its growth, with the optimal concentration being 40-70 mM. The growth rate of M45 was as high as that of the wild-type cells when ammonium was the nitrogen source. The 45-kDa protein was absent in M45 irrespective of the growth conditions. The activities of nitrate and nitrite reductases were higher in M45 than in wild type. The rate of nitrate-dependent O(2) evolution in wild type measured in the presence of L-methionine D,L-sulfoximine and D,L-glyceraldehyde showed saturation kinetics with respect to nitrate concentration in the external medium. The nitrate concentration required to produce half the maximal rate was 1 muM. In M45, the rate of nitrate-dependent O(2) evolution was nearly zero at nitrate concentrations <1 mM and was linearly increased as the concentration increased. The presumed absence of nitrate transport in M45 demonstrated by these results suggested that the 45-kDa protein is a nitrate transporter.