Effective decoration of Pd nanoparticles on the surface of SnO2 nanowires for enhancement of CO gas-sensing performance

Decoration of noble metal nanoparticles (NPs) on the surface of semiconducting metal oxide nanowires (NWs) to enhance material characteristics, functionalization, and sensing abilities has attracted increasing interests from researchers worldwide. In this study, we introduce an effective method for the decoration of Pd NPs on the surface of SnO2 NWs to enhance CO gas-sensing performance. Single-crystal SnO2 NWs were fabricated by chemical vapor deposition, whereas Pd NPs were decorated on the surface of SnO2 NWs by in situ reduction of the Pd complex at room temperature without using any linker or reduction agent excepting the copolymer P123. The materials were characterized by advanced techniques, such as high-resolution transmission electron microscopy, scanning transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The Pd NPs were effectively decorated on the surface of SnO2 NWs. As an example, the CO sensing characteristics of SnO2 NWs decorated with Pd NPs were investigated at different temperatures. Results revealed that the gas sensor exhibited excellent sensing performance to CO at low concentration (1-25ppm) with ultrafast response-recovery time (in seconds), high responsivity, good stability, and reproducibility.

Ischemic brain metabolism in patients with chronic cerebrovascular disease: Increased oxygen extraction fraction and cerebrospinal fluid lactate

The aim of the present study is to elucidate the existence of chronically ischemic metabolism concomitant with misery perfusion of the brain in patients with chronic cerebrovascular disease. For this purpose, we measured cerebral blood flow (CBF) and oxygen metabolism by positron emission tomography (PET) and also determined cerebrospinal fluid (CSF) lactate as an indicator of the ischemic brain metabolism. Twenty-eight patients with chronic ischemic stroke and transient ischemic attack (TIA), who had angiographically occlusive (n = 11), stenotic (n = 10), and nonstenotic changes (n = 7) of the carotid artery and/or the intracranial major artery, were selected for this study. CBF, oxygen extraction fraction (OEF), cerebral metabolic rate for oxygen (CMRO2), and cerebral blood volume (CBV) were determined by PET, and CSF lactate and pyruvate were determined by enzymatic method in the patients with various grades of stenotic changes of the carotid artery. There were no significant differences in PET parameters and CSF variables among the groups of the occlusive, stenotic, and nonstenotic carotid artery. However, CSF lactate was correlated negatively with mean bilateral hemispheric (m)CBF (R(2) = 0.229, P<.01), positively with mOEF (R(2) = 0.278, P<.005) and more highly with mCMRO2/CBF (absolute extraction of oxygen content to the brain) (R(2) = 0.473, P<.0001) in all patients. There was no correlation between CSF lactate and mCMRO2 or mCBV. None of the cases in the nonstenotic group showed mOEF greater than 0.45, or mCMRO2/CBF greater than 7.9 vol%, while 80% of the cases in the stenotic group and 82% of the cases in the occlusive group showed mOEF and mCMRO2/CBF exceeding the above-mentioned values, respectively. The present findings, that increased mOEF and mCMRO2/CBF were significantly correlated with increased CSF lactate, indicate the brain to be in a metabolically ischemic state or increased anaerobic glycolysis with oxygen metabolism maintained in patients with chronic ischemic stroke.

Regulation of decidualization in human endometrial stromal cells through exchange protein directly activated by cyclic AMP (Epac)

INTRODUCTION

Human endometrial stromal cells (ESCs) undergo differentiation during the decidualization process. Decidualization is characterized by their enhanced production of IGF binding protein-1 (IGFBP-1), prolactin (PRL), and the forkhead transcriptional factor FOXO1, and transformation into more rounded cells, during the secretory phase of the menstrual cycle and subsequent pregnancy. Protein kinase A (PKA)-mediated cAMP signaling is crucial for this process. The present study was undertaken to examine the involvement of a mediator of cAMP signaling, exchange protein directly activated by cAMP (Epac), in decidualization of cultured ESCs.

RESULTS

Treatment of ESCs with the Epac-selective cAMP analog 8-CPT-2-OMe-cAMP (CPT) had no effect on IGFBP-1, PRL, and FOXO1 mRNA expression. However, CPT potentiated IGFBP-1 and PRL expression stimulated by the PKA-selective cAMP analog N(6)-Phe-cAMP (Phe) and activated Rap1, a downstream regulator of Epac signaling. Knock-down of Epac1, Epac2, or Rap1 significantly inhibited the Phe- or Phe/CPT-induced increase in IGFBP-1 and PRL expression, as well as Rap1 activation. Furthermore, CPT enhanced IGFBP-1 and PRL expression and the morphological differentiation induced by ovarian steroids, whereas Epac1, Epac2, or Rap1 knock-down suppressed these events.

CONCLUSION

These data provide evidence for the involvement of the Epac/Rap1 signaling pathway in cAMP-mediated decidualization of human ESCs.

Risk of surgical glove perforation in oral and maxillofacial surgery

Oral and maxillofacial surgery, which involves several sharp instruments and fixation materials, is consistently at a high risk for cross-contamination due to perforated gloves, but it is unclear how often such perforations occur. This study aimed to address this issue. The frequency of the perforation of surgical gloves (n=1436) in 150 oral and maxillofacial surgeries including orthognathic surgery (n=45) was assessed by the hydroinsufflation technique. Orthognathic surgery had the highest perforation rate in at least 1 glove in 1 operation (91.1%), followed by cleft lip and palate surgery (55.0%), excision of oral soft tumour (54.5%) and dental implantation (50.0%). The perforation rate in scrub nurses was 63.4%, followed by 44.4% in surgeons and first assistants, and 16.3% in second assistants. The odds ratio for the perforation rate in orthognathic surgery versus other surgeries was 16.0 (95% confidence interval: 5.3-48.0). The protection rate offered by double gloving in orthognathic surgery was 95.2%. These results suggest that, regardless of the surgical duration and blood loss in all fields of surgery, orthognathic surgery must be categorized in the highest risk group for glove perforation, following gynaecological and open lung surgery, due to the involvement of sharp objects.

Parametric correlations versus fidelity decay: the symmetry breaking case

We provide formulas for fidelity decay and parametric energy correlations for random matrix ensembles where time-reversal invariance of the original Hamiltonian is broken by the perturbation. Like in the case of a symmetry conserving perturbation a simple relation between both quantities exists. Fidelity freeze is observed for systems with even and odd spin.

Locoregional recurrence risk factor and indications for postmastectomy radiotherapy in Japanese patients with tumors 5 cm or larger

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Background: Locoregional recurrence (LRR) after mastectomy reduces the patient’s quality of life and survival. There is a consensus that postmastectomy radiotherapy (PMRT) helps achieve locoregional control and reduces LRR. However, in patients with large tumors, the question of which variables affect the likelihood of LRR and the role of PMRT has been the subject of substantial controversy. This study investigated what are risk factors for LRR and the efficacy of PMRT in this Japanese patient population.

Methods: This study examined 589 cases of invasive breast carcinoma with tumors 5 cm or larger from 1998 to 2008. We divided the study population into 3 groups: patients with negative nodes, 1-3 positive nodes, and ≥4 positive nodes. The relationship between various clinicopathological variables and LRR was examined and the relationship between LRR and PMRT was estimated.

Results: During the median follow-up was 44.2 months, 38 (6.5%) patients experienced LRR. In the multivariate analysis, independent predictors of LRR include pectoral invasion in patients with 1-3 positive nodes, and severity lymphatic invasion, estrogen receptor-negative status, and nodal ratio of positive/excised nodes ≥ 0.50 in patients with ≥4 positive nodes. In patients without positive nodes, none of the examined variables were significantly associated with LRR. PMRT did not improve the outcome of the patients at highest risk who had these variables.

Conclusions: The efficacy of PMRT in patients with large tumors was not shown. In the context of systemic therapy and adequate lymph node dissection, PMRT by itself had a limited role in providing locoregional control. Due to the very low incidence of LRR observed, PMRT was not necessary for patients with large tumors without lymph node metastasis. The indication for PMRT in patients with metastatic nodes remains controversial.

Infrared spectroscopic and electron microscopic characterization of gold nanogap structure fabricated by focused ion beam

Using infrared spectroscopy of plasmonic resonances and mapping of elemental composition and structure, we investigated the correlation between optical and structural properties of nanometre-scale gaps in gold nanorod dimers fabricated by electron beam lithography (EBL) and focused ion beam (FIB) milling. In spite of their very similar scanning electron microscopy (SEM) images, a fully cut nanogap and a shallower cut with slight imperfection near the gap region were clearly distinguished by their strongly different infrared plasmonic resonance behaviour. The differences in the infrared spectra are related to different structural and chemical results from elaborated cross-sectional transmission electron micrographs and energy dispersive x-ray spectrometry (EDX) mapping of the gap region.

Abstract P1-12-07: Neo-Adjuvant Exemestane in Post Menopausal Estrogen and/or Progesterone Receptor Positive Breast Cancer: A Randomized Phase II Trial To Investigate Optimal Duration (4 Month Versus 6 Month) of Preoperative Endocrine Therapy (PTEX46 Trial)

Background: Since the 1990s, primary endocrine therapy has been considered the gold standard in the adjuvant and metastatic treatment settings for estrogen and/or progesterone receptor (ER and/or PgR) positive breast cancer. This therapy has also been shown to be effective as neo-adjuvant endocrine therapy in these indications. In recent years, the focus of clinical interest has shifted to the third-generation aromatase inhibitors from tamoxifen. The optimal treatment duration time and causal relationship between neo-adjuvant endocrine therapy and survival, however, are not clear. We therefore conducted the present study to investigate the potential benefits of neo-adjuvant exemestane (E) therapy with the goal of identifying the optimal treatment duration (4 months versus 6 months).

Methods: Conducted at three hospitals in Japan, this study was a multicenter, randomized phase II trial of pre-operative E treatment in postmenopausal women with untreated primary breast cancer. Fifty postmenopausal women with ER positive and/or PgR positive invasive breast cancer were randomly assigned to E (25 mg/day) for 4 months (4 mo) or E (25 mg/day) for 6 months (6 mo). All patient data were collected by UMIN and were analyzed by the National Cancer Center in Japan. Tumor regression (by clinical examination, ultrasound, and MRI), pathological response, shift towards breast-conserving surgery, and safety assessments were the main outcome measures.

Results: Of the 50 patients that enrolled, 28 patients had undergone surgery. The mean ages in the 4 mo and 6 mo treatment groups were 66.7 years and 66.8 years, respectively. No significant differences in the patient characteristics were found in the two groups. The response rates (partial or complete responses) by clinical examination in the 4 mo and 6 mo groups were 37.5% and 50%, respectively. Pathological responses (minimal response or better) were found in 13.3% and 41.7% of patients and a partial mastectomy was performed in 50.0% and 58.3% of patients after 4 mo and 6 mo, respectively.

Conclusion: To date, the results of this study demonstrate that treatment with E for 6 mo was more efficacious than treatment with E for 4 mo. Further work is in progress to obtain data from additional patients and to identify the optimal duration of neo-adjuvant E.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-12-07.

Angiotensin II receptor blockade with valsartan decreases plasma osteopontin levels in patients with essential hypertension

Osteopontin (OPN) has recently emerged as a key factor in both vascular remodelling and development of atherosclerosis. It has been reported that OPN is regulated by the renin-angiotensin-aldosterone system (RAAS). The aim of this study was to clarify the effect of angiotensin II receptor blockade with valsartan on plasma OPN levels in patients with essential hypertension (EHT). Forty-six patients (mean age, 64±11 years) with EHT were randomly assigned to treatment with amlodipine or valsartan. There were no significant differences in baseline clinical characteristics between the two groups. Blood sampling and blood pressure evaluation were performed before and after 24 weeks of treatment. After 24 weeks, both systolic blood pressure (SBP) and diastolic blood pressure (DBP) were decreased significantly and by the same degree in each treatment group. However, valsartan but not amlodipine decreased plasma OPN levels (baseline and 24-week data-valsartan: 614±224 ng ml(-1), 472±268 ng ml(-1), P=0.006; amlodipine: 680±151 ng ml(-1), 687±234 ng ml(-1), P>0.999). A positive correlation between the reduction in OPN and the log natural (ln) C-reactive protein (CRP) was seen in the valsartan-treated group. Stepwise regression analysis showed that treatment with valsartan and the reduction of ln CRP were associated with the reduction in OPN levels, and this association was independent of the reduction in SBP or aldosterone levels (valsartan: β=0.332, P=0.026; ln CRP reduction: β=0.366, P=0.015). These results suggest that suppression of the RAAS and inflammation may decrease plasma OPN levels.

Machine perfusion preservation for kidney grafts with a high creatinine from uncontrolled donation after cardiac death

BACKGROUND

This study evaluated the usefulness of machine perfusion preservation parameters as selection criteria for donation after cardiac arrest (DCD) with high creatinine level. The aim of this study is to evaluate to whether DCD donor >50 years old and with high creatinine are acceptable.

METHODS

We examined 17 kidneys from uncontrolled DCD who showed creatinine levels >3.0 mg/dL before procurement. The study included the following two groups: group 1 (n = 9), donor age <50 years old versus group 2 (n = 8), donor age >50 years old.

RESULTS

There were no significant differences in donors or preservation conditions among the 2 groups, including age, terminal creatinine, warm ischemic time, cold perfusion time, and total ischemic time. A greater resistance of 47.9 mmHg/mL per min/g was observed among group 2, compared with 42.5 mmHg/mL per min/g in group 1. A shorter ATN period (8.2 days) was noted in group 1, compared with 21.2 days for group 2. The flow rate (mL/g/min) was not significantly different between the two groups. The best-Cr level was 1.22 mg/dL in group 1 and 1.94 mg/dL in group 2.

CONCLUSION

Machine perfusion flow was a reliable indicator of graft viability in uncontrolled DCD, particularly kidneys with high creatinine level. Even older donors were acceptable if the machine perfusion preservation parameters such as flow rate and pressure were acceptable; however, they may show severe delayed graft function.