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Using proprietary account-level transaction data in the futures market where day traders are self-declared ex ante, this study investigates whether day traders enhance price discovery at the market level. From a natural classification of day traders, we find that heterogeneous day traders have differential effects on price discovery. Self-declared day traders, who benefit from low margin requirement, do not improve price discovery measured by information share. In contrast, non-declared traders, who are not self-declared as day traders, improve price discovery. Their positive impacts on price discovery are particularly significant during periods of high volatility and arrival of new information. Overall, a margin stimulating policy may encourage more day trading, but may also attract overconfident investors, especially inexperienced ones, and who do not enhance price discovery.

Background 18F-FDG PET/CT has been wildly used in cancer screening. However, FDG accumulates not only in malignant lesions but also in inflammatory processes, which are frequently observed in normal subjects. We investigated PET/CT images in healthy subjects and identified the correlation between quantitative values of images and clinical characteristics. Method 105 subjects undergoing PET/CT scans for health examinations were retrospectively collected. The standardized uptake value (SUVmax) in the nasopharyngeal (NP) region, neck lymph nodes (LNs), palatine tonsil, mediastinal or pulmonary LNs were evaluated. The correlation between the SUVmax and the clinical variables was assessed. Results There is strong negative correlation between the SUVmax of palatine tonsils and age (p =0.0004), strong positive correlation between the SUVmax of mediastinal LNs and age (p =0.0004). There’s positive correlation between the SUVmax of palatine tonsils and cholesterol (p =0.03), the SUVmax of neck LNs and serum CRP level (p = 0.04). Conclusion Age may have different effect on SUVmax of palatine tonsils and mediastinal LNs. While serum level of Cholesterol and CRP may be related to higher FDG uptake. Understanding clinical characteristics of subjects may help the interpretation of PET/CT images for cancer screening.

Background F-18 Fluorodeoxyglucose positron emission tomography with computed tomography (FDG PET/CT) is a powerful tool in oral cancer. However, the oral cavity is a small cavity with complex components. An invasive cancer or post-therapy change frequently cause difficulty in interpretation. In this study, we established a tongue depressor (TD)-assisted FDG PET/CT protocol to solve this problem. Methods We enrolled 264 patients with oral cancers. Early and delayed images were acquired in each FDG PET/CT examination. A wooden tongue depressor was placed either between buccal mucosa and teeth or between tongue border and teeth in delayed image. TD placed delayed image was compared with early images to analyze the extent of tumor. The discrimination ratio (DR) of the tumor was calculated as: (images that can clearly distinguish features /all images) × 100%. Results In tongue cancer group, the DR of the tumors were 26.1% on early images and 99.3% on TD placed delayed images (p

Background and purpose: Histone deacetylase (HDAC) inhibitors (HDIs) were shown to modulate the epithelial-mesenchymal transition (EMT) progression and inhibit the migration and invasion of cancer cells. Emerging as a novel class of anti-cancer drugs, HDIs have attracted much attention in the field of drug discovery. This study aimed to the underlying mechanisms of Honokiol in preventing the metastatic dissemination of gastric cancer cells by inhibiting HDAC3 activity/expression.Experimental Approach: Clinical pathological analysis was performed to determine the relationship between HDAC3 and tumor progression. The effects of Honokiol on pharmacological characterization, functional, transcriptional activities, organelle structure changes, and molecular signalings were analyzed using binding assays, Differential Scanning Calorimetry, luciferase reporter assay, HDAC3 activity, ER stress response element activity, transmission electron microscopy, immune-blotting and Wnt/b-catenin activity assays. The in vivo effects of Honokiol on peritoneal dissemination were determined by a mouse model and detected by the PET/CT tomography.Key Results: HDAC3 over-expression was correlated with poor prognosis. Honokiol significantly abolished HDAC3 activity (Y298) via inhibition of NFκBp65/CEBPb signaling, which was reversed by the over-expression of plasmids of NFκBp65/CEBPb. Honokiol-inhibited NFκBp65/CEBPb activation could be reversed by 4-phenylbutyric acid (a chemical chaperone) and calpain-2 gene silencing. Honokiol increased ER stress markers and inhibited EMT-associated epithelial markers, but decreased Wnt/β-catenin activity. Suppression of HDAC3 by both Honokiol and HDAC3 gene silencing decreased cell migration and invasion in vitro and metastasis in vivo. Conclusions and Implications: Honokiol acts by suppressing HDAC3-mediated EMT and metastatic signaling. By prohibiting HDAC3, metastatic dissemination of gastric cancer may be blocked.

Background and purpose Histone deacetylase (HDAC) inhibitors (HDIs) can modulate the epithelial-mesenchymal transition (EMT) progression and inhibit the migration and invasion of cancer cells. Emerging as a novel class of anti-cancer drugs, HDIs are attracted much attention in the field of drug discovery. This study aimed to discern the underlying mechanisms of Honokiol in preventing the metastatic dissemination of gastric cancer cells by inhibiting HDAC3 activity/expression. Experimental approach Clinical pathological analysis was performed to determine the relationship between HDAC3 and tumor progression. The effects of Honokiol on pharmacological characterization, functional, transcriptional activities, organelle structure changes, and molecular signaling were analyzed using binding assays, differential scanning calorimetry, luciferase reporter assay, HDAC3 activity, ER stress response element activity, transmission electron microscopy, immune-blotting, and Wnt/β-catenin activity assays. The in vivo effects of Honokiol on peritoneal dissemination were determined by a mouse model and detected by PET/CT tomography. Key results HDAC3 over-expression was correlated with poor prognosis. Honokiol significantly abolished HDAC3 activity (Y298) via inhibition of NFκBp65/CEBPβ signaling, which could be reversed by the over-expression of plasmids of NFκBp65/CEBPβ. Treatments with 4-phenylbutyric acid (a chemical chaperone) and calpain-2 gene silencing inhibited Honokiol-inhibited NFκBp65/CEBPβ activation. Honokiol increased ER stress markers and inhibited EMT-associated epithelial markers, but decreased Wnt/β-catenin activity. Suppression of HDAC3 by both Honokiol and HDAC3 gene silencing decreased cell migration and invasion in vitro and metastasis in vivo. Conclusions and implications Honokiol acts by suppressing HDAC3-mediated EMT and metastatic signaling. By prohibiting HDAC3, metastatic dissemination of gastric cancer may be blocked. Graphical abstract Conceptual model showing the working hypothesis on the interaction among Honokiol, HDAC3, and ER stress in the peritoneal dissemination of gastric cancer. Honokiol targeting HDAC3 by ER stress cascade and mitigating the peritoneal spread of gastric cancer. Honokiol-induced ER stress–activated calpain activity targeted HDAC3 and blocked Tyr298 phosphorylation, subsequently blocked cooperating with EMT transcription factors and cancer progression. The present study provides evidence to demonstrate that HDAC3 is a positive regulator of EMT and metastatic growth of gastric cancer cells. The findings here imply that overexpressed HDAC3 is a potential therapeutic target for honokiol to reverse EMT and prevent gastric cancer migration, invasion, and metastatic dissemination. • Honokiol significantly abolished HDAC3 activity on catalytic tyrosine 298 residue site. In addition, Honokiol-induced ER stress markedly inhibited HDAC3 expression via inhibition of NFκBp65/CEBPβ signaling. • HDAC3, which is a positive regulator of metastatic gastric cancer cell growth, can be significantly inhibited by Honokiol. • Opportunities for HDAC3 inhibition may be a potential therapeutic target for preventing gastric cancer metastatic dissemination.

Transthyretin cardiac amyloidosis (ATTR-CM) is an increasingly recognized cause of heart failure with preserved ejection fraction. Favorable prognosis depends on early diagnosis and correct treatment strategy. Among patients for whom there is a high clinical suspicion of cardiac amyloidosis, (99m)Tc-labeled bone avid scintigraphy including (99m)Tc-pyrophosphate (PYP) scintigraphy may be of diagnostic and prognostic importance. Various international guidelines support the non-biopsy diagnosis of ATTR-CM using (99m)Tc-PYP scintigraphy, yet emphasize the gap in standardization of acquisition and imaging analysis protocols, as well as the appropriateness of its clinical use. Therefore, a joint expert consensus has been reached by the Taiwan Society of Cardiology and the Society of Nuclear Medicine of the Republic of China, to advocate for the application of (99m)Tc-PYP scintigraphy in the diagnosis of ATTR-CM. This article aims to highlight the recommendations on image acquisition, qualitative and quantitative assessments of cardiac (99m)Tc-PYP uptake, and diagnostic algorithms. We hope the implementation of these recommendations in Taiwan will facilitate the process and enhance the diagnostic rate of ATTR-CM.

Gated myocardial perfusion SPECT (GMPS) provides a one-stop-shop evaluation for cardiac resynchronization therapy (CRT). However, conflicting results have been observed regarding whether the baseline left-ventricular (LV) mechanical dyssynchrony as assessed by phase analysis on GMPS was predictive of therapeutic response to CRT. Since dyssynchrony parameters by phase analysis spuriously increased by scarred myocardium, the purpose of this study was to explore the value of dyssynchrony after stripping off the scar region in correlation to mechanical response to CRT. Forty-seven patients following standard indications for CRT received GMPS with phase analysis as pre-CRT evaluation. A decrease of end-systolic volume (ESV) > 15% on follow-up echocardiography after CRT was considered as a mechanical response to CRT. Myocardial regions with less than 50% of maximal activity on GMPS were considered as a scar. The phase standard deviation (PSD) and histogram bandwidth (BW) without or with stripping off scar were assessed by phase analysis of GMPS and were used for evaluation of LV dyssynchrony of all myocardium or only the viable myocardium, respectively. No significant difference was noted between mechanical responders (31 of 47 patients, 66%) and nonresponders ( 16 of 47 patients, 34%) for PSD (48.6° ± 19.4° vs 43.9° ± 20.7°, p = 0.46) and BW (225° ± 91.1° vs 163.5° ± 94.6°, p = 0.38) of the entire myocardium. However, responders had significantly larger PSD (40.5° ± 15.7° vs 30.5° ± 13.2°, p = 0.03) and borderlinely larger BW (215° ± 91.2° vs. 139.5° ± 78.2°, p = 0.05) than non-responders after stripping off scar. Logistic regression analysis showed that scar area and PSD after stripping off scar were independent predictors of mechanical response. Our result showed that LV dyssynchrony of the entire myocardium did not predict response to CRT. However, LV dyssynchrony only in the viable myocardium was a significant predictor of CRT mechanical response.

We conducted a clinical trial to analyze human serum containing carbamazepine by using the differential pulse voltammetry (DPV) method with a glassy carbon electrode, and compared it with the fluorescence polarization immunoassay (FPIA). Thirty patients, who visited our hospital to have their serum carbamazepine level checked, were enrolled. Ten mL of venous blood was collected from each patient and analyzed by DPV and FPIA methods. The correlation between the carbamazepine concentrations determined by DPV and FPIA was good, with an RSQ of 0.998. The similarity of the results indicates that these two methods can be used interchangeably. The DPV method using a glassy carbon electrode may be a potential alternative method to determine the carbamazepine level in human serum.

This study examines the relationships between the herding of various investor groups andtrading noise in the Taiwan stock market to determine whether any of the investor groupstend to herd rationally. The study uses a unique and comprehensive data set on intradaytransactions and limit order books of the Taiwan Stock Exchange (TWSE). We calculate thehigh-frequency herding measures and trading noise in a call auction market. We find thatinstitutional investors are likely to be informed traders and herd rationally based on superiorinformation. Institutional investors’ herding has a negative impact on trading noise. Theirbuy (sell) herding predicts positive (negative) future market returns. By contrast, the herdingof individual investors tends to contain limited information, as it increases trading noise; thebuy (sell) herding of individuals is negatively correlated with future market returns. Thesefindings are more significant for stocks with higher turnover.Keywords Trading noise; Herding; Institutional investors; Individual investors; Intradaytransactions.JEL Classification: G1, G12, G14, G15, L11*Acknowledgements: The authors thank the editors and the two anonymous referees for theirconstructive comments. The authors also acknowledge the financial support from NationalScience Council of Taiwan (Grant no. NSC 99-2410-H-032-030-), as well as the Taiwan StockExchange for data support.**Corresponding author: Shih-Chuan Tsai, 11F-2, No.18, Jin-Shan South Road, Section 2,Taipei, Taiwan. Tel: +886-277343299, Fax: +886-2-23222668. email: chuant@ntnu.edu.tw.

In this study, we employ a statistical arbitrage approach to demonstrate that momentum investment strategy tend to work better in periods longer than six months, a result different from findings in past literature. Compared with standard parametric tests, the statistical arbitrage method produces more clearly that momentum strategies work only in longer formation and holding periods. Also they yield positive significant returns in an up market, but negative yet insignificant returns in a down market. Disposition and over-confidence effects are important factors contributing to the phenomenon. The over-confidence effect seems to dominate the disposition effect, especially in an up market. Moreover, the over-confidence investment behavior of institutional investors is the main cause for significant momentum returns observed in an up market. In a down market, the institutional investors tend to adopt a contrarian strategy while the individuals are still maintaining momentum behavior within shorter periods. The behavior difference between investor groups explains in part why momentum strategies work differently between up and down market states. Robustness tests confirm that the momentum returns do not come from firm size, overlapping execution periods, market states definition or market frictions.

The purpose of the present study was to conduct a systematic review and meta-analysis of the published literature to assess the diagnostic performance of FDG-PET or PET/CT in the detection of recurrent colorectal cancer (CRC) rising in patients with elevated CEA. The authors conducted a systematic MEDLINE search of published articles. Two reviewers independently assessed the methodological quality of each study. We estimated pooled sensitivity and specificity and positive and negative likelihood ratios, and summary receiver-operating characteristic curves in the detection of recurrent CRC in patients with elevated CEA. Eleven studies with a total of 510 patients met the inclusion criteria. One hundred and six patients (106/510 = 20.8 %) had true-negative FDG-PET (PET/CT) results in detection of recurrent CRC when rising CEA. The pooled estimates of sensitivity and specificity and positive and negative likelihood ratios of FDG-PET in the detection of tumor recurrence in CRC patients with elevated CEA were 90.3 % (95 % CI, 85.5–94.0 %), 80.0 % (95 % CI, 67.0–89.6 %), 2.88 (95 % CI, 1.37–6.07), and 0.12 (95 % CI, 0.07–0.20), respectively. The pooled estimates of sensitivity and specificity and positive and negative likelihood ratios of FDG-PET/CT in the detection of tumor recurrence in CRC patients with elevated CEA were 94.1 % (95 % CI, 89.4–97.1 %), 77.2 % (95 % CI, 66.4–85.9 %), 4.70 (95 % CI, 0.82–12.13), and 0.06 (95 % CI, 0.03–0.13), respectively. Whole-body FDG-PET and PET/CT are valuable imaging tools for the assessment of patients with suspected CRC tumor recurrence based on the increase of CEA.

A 53-year-old female patient suffered from pain in almost her entire body, particularly the joints. Chest computed tomography revealed multiple lymphadenopathies over cervical, mediastinal, and axillary areas. A fluorine-18-deoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) revealed increased FDG uptake in many lymph nodes and the spleen. Lymphoma was suspected. However, the result of a biopsy showed no malignancy, and the gallium-67 citrate scan showed no gallium-avid tumor throughout the whole body. Adult-onset Still's disease was diagnosed and the patient responded well to steroid therapy. The follow-up PET/CT six months later showed complete remission of the FDG-avid lesions seen in the previous PET/CT. Our study suggests that FDG PET/CT combined with gallium-67 scan may be helpful in diagnosing patients with adult-onset Still's disease. In addition, the use of FDG PET/CT alone may be useful for the evaluation of disease distribution, disease activity, and therapeutic response.

This paper provides new evidence on the relations between managerial and institutional ownerships and firm performance. These relations are found to be affected by firm’s stock price informativeness and corporate governance. Based on a sample of US firms from NYSE, AMEX, and NASDAQ between 1989 and 2006, we document three important findings. First, managerial ownership and firm future performance are non-linearly related; the positive relation is stronger for firms with less informative prices or more agency problems. This finding suggests that poor governance and uninformative price increase the importance of managerial value creation for their firms by improving internal governance. Second, institutional ownership has a significant positive impact on firm future performance, with larger impact for firms with less informative prices or good governance. However, institutional ownership, which reflects external monitoring, has a weaker positive effect compared to managerial ownership, which controls for internal governance. Third, the interaction between managerial ownership and institutional ownership has a significant positive impact on firm future performance, suggesting that there are synergistic effects of internal and external corporate governance mechanisms in improving firm value.

This paper develops a dynamic model of the financing and operating decisions of firms in the presence of information asymmetry. When the value of growth opportunities is not fully recognized, securities are undervalued, thus influencing the financing and investment decisions. The agency-based underinvestment problem is re-examined under information asymmetry. For firms with greater growth opportunities, the investment distortion resulting from information asymmetry is especially significant. Information asymmetry also increases the expected bankruptcy cost. The cost of information asymmetry in terms of both the firm value and the information spread under the optimal capital structure could be substantial.

Cardiac resynchronization therapy (CRT) can provide cardiac reverse remodeling (RR), which may include mechanical reverse remodeling (MRR) and/or electrical reverse remodeling (ERR). However, uncoupling of MRR and ERR is not uncommon, and the underlying mechanisms are not clear. This study aimed to evaluate the relationship of myocardial substrate characteristics as assessed by myocardial perfusion imaging (MPI) and cardiac RR post-CRT. Forty-one patients (26 men, mean age 66 ± 10 years) with heart failure received CRT for at least 12 months were assigned to three groups according to their levels of RR: I, MRR + ERR (ESV reduced ≥15 % and intrinsic QRS duration reduced ≥10 ms); II, MRR only (ESV reduced ≥15 %); and III, non-responder (the others). All the patients also underwent MPI under transient CRT-off to evaluate the intrinsic myocardial substrates, including myocardial scar, LV volumes and function, systolic dyssynchrony, and activation sequences. In addition, ventricular tachycardia (VT) and ventricular fibrillation (VF) detected by the CRT devices during follow-up periods were also recorded. Quantitative analysis of MPI showed that there were significant differences for scar burden [15.9 ± 9.5, 26.8 ± 16.1, and 45.6 ± 15.1 % for group I (n = 15), II (n = 16), and III (n = 10), respectively, p

Ventricular arrhythmia is the major cause of sudden cardiac death for patients with heart failure, including those receiving implantation of cardiac resynchronization therapy (CRT). The purpose of this study was to assess the value of myocardial perfusion SPECT (MPS) in predicting ventricular arrhythmia for patients with CRT.Fifty-one patients (35 males, mean age 64 ± 12 years) who had received CRT for at least 6 months were enrolled for resting gated MPS. Three main quantitative parameters of MPS, including extent of myocardial scar, left ventricular ejection fraction (LVEF) and LV dyssynchrony (phase SD), were generated by Emory Cardiac Toolbox. Using the recorded ventricular arrhythmia in the device, including ventricular tachycardia (VT) and ventricular fibrillation (VF), as the primary end point, the value of quantitative parameters of MPS in predicting the development of VT/VF was assessed.Twenty (39 %) of the 51 patients developed VT/VF during the follow-up (15.3 ± 12.7 months). The patients with VT/VF had significantly lower LVEF (24 ± 12 vs. 36 ± 17 %, p0.005), larger scar areas (36 ± 19 vs. 22 ± 12 %, p0.05) and larger phase SD (57° ± 20° vs. 43° ± 17°, p0.01). When categorizing the patients by the median values of LVEF, scar and phase SD, univariate regression analysis showed that lower LVEF (29 %), larger scar (23 %) and larger phase SD (50°) were related to the development of VT/VF (p = 0.006, 0.011 and 0.064, respectively). However, only LVEF was marginally significant as an independent predictor of VT//VF on multivariate regression analysis (p = 0.0573). Survival analysis with Kaplan-Meier curves showed that the survival probability for VT/VF in those with LVEF29 %, scar areas23 % and phase SD50° was significantly better than in the others (HR 5.16, 95 % CI 1.20-22.16) by log-rank test (χ (2) = 5.9894, p = 0.014).Lower LVEF, larger scar and/or more dyssynchrony assessed by MPS were related to the development of ventricular arrhythmia for patients with CRT, and further defibrillator implantation may be considered for these patients.

In clinical medicine improved diagnostic methods for the detection of infection are needed. A good infectious animal model is very important for the development of a new diagnostic method or drug. The purpose of this study was to establish a good animal model with soft tissue infection. Twenty-four SD rats were divided into four groups (6 in each group). Various bacilli including Staphylococcus aureus (S. aureus), Streptococcus pneumoniae (S. pneumoniae), and Escherichia coli (E. coli) were injected intramuscularly into the left caudal thighs of three groups of rats to create soft tissue infection. In addition, normal saline was injected into the left caudal thighs of ten rats which were used as controls. Before and 48 hr after inoculation of the bacilli, a blood sample (0.5 ml) was taken from each rat and analyzed to determine the white blood cell count and differentiated cell count. In addition, 48 hr after the inoculation, 0.2 mCi of gallium-67 was injected via the tail vein. Gallium scan was performed at 24 hr and 48 hr after administration of the radiotracer. The dorsal view of both hind legs was imaged and analyzed by computers to calculate the lesion-to-normal (L/N) ratio. After imaging, all rats were sacrificed and specimens from portions of the infected thigh muscle were sent for histopathologic investigation to confirm the infection. The increase in both the WBC counts and the segmented polymorphonuclear leukocytes (PMNs) were most significant in the S. aureus group, followed by the S. pneumoniae group, E. coli group and normal control groups. The rats with S. aureus infection had significant gallium uptake at the site of infection and the highest L/N ratio of 2.14 on the 24-hr image and 2.0 on the 48-hr image. The rats with S. pneumoniae had the second highest L/N ratio (1.41 at 24 hr, and 1.48 at 48 hr). The L/N ratio for the E. coli group was 1.27 at 24 hr and 1.35 at 48 hr. No obviously abnormal gallium uptake was demonstrated in the normal controls. We conclude that all three bacilli induced a soft tissue infection in SD rats. S. aureus resulted in the most significant infectious signs.

The purpose of the present study was to predict the response of malignant lymphomas (MLs) to chemotherapy using technetium-99m methoxyisobutylisonitrile (Tc-MIBI) scan and to compare it with the predictive ability of P-glycoprotein (P-gp) expression, multidrug resistance-related protein (MRP) expression and other prognosis factors. Twenty-five ML patients were enrolled in this study prior to initiation of chemotherapy. Images were obtained 10 min after intravenous injection of Tc-MIBI, interpreted visually and the tumour-to-background (T/B) ratios calculated. Immunohistochemical analyses were performed on sections of the biopsy specimens to determine P-gp and MRP expression. Chemotherapy response was evaluated in the first 1-2 years after completion of chemotherapy. The mean T/B ratio of the 15 patients with a good response (3.3 +/- 0.6) was significantly higher than that of the 10 patients with a poor response (1.2 +/- 0.1). All 15 patients with a good chemotherapy response had positive Tc-MIBI scan results and negative P-gp and MRP expression. All 10 patients with a poor response had negative Tc-MIBI scan results and either positive P-gp or MRP expression. Other prognosis factors showed no significant difference in the incidence of good and poor responses. Tc-MIBI scan results represent P-gp or MRP expression more accurately than other prognosis factors and predict the chemotherapy response in ML patients.

Background: The purpose of this preliminary study was to evaluate the efficacy of positron emission tomography (PET) with [ 18 F]fluoro-2-deoxyglucose (FDG) for differentiating benign from malignant solitary pulmonary nodules. Methods: Twenty-six patients (12 females, 14 males, age 27‐79 years) with radiographically indeterminate solitary pulmonary nodules underwent FDG-PET and the findings were compared with the results of pathological examination of biopsy samples. FDG activity in the lesion was expressed as the ratio of lesion-to-background counts (L/B ratio) for semiquantitative analysis. Results: The mean L/B ratio of malignant lesions (8.81 ± 3.71, n = 20) was not significantly higher than that of benign lesions (4.71 ± 3.00, n =6 ) (p = 1.00). Using a cut-off L/B ratio of 5.0 for malignancy, FDG-PET correctly detected 19 true positive and three true negative cases, but failed to detect three false positive (two abscesses and one cryptococcus) cases and one false negative (adenocarcinoma) case. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value were 95, 50, 86, 75 and 85%, respectively. Conclusions: FDG-PET is a sensitive modality for detecting malignancy, but is not specific enough. Benign lung lesion with active inflammation could demonstrate high FDG uptake, making it difficult to differentiate from malignancy. In the future, we will increase the case numbers to evaluate further the utility of FDG-PET for differentiating radiographically indeterminate solitary pulmonary nodules.

BACKGROUND The diagnostic accuracy of combined computed tomography (CT) and technetium 99m tetrofosmin (Tc-TF) single photon emission computed tomography (SPECT) of head and neck to differentiate recurrent or residual nasopharyngeal carcinomas (NPCs) from benign lesions after radiotherapy was evaluated and compared with positron emission tomography (PET) with 18-fluoro-2-deoxyglucose (FDG). METHODS Four months after radiotherapy, 36 patients with NPC underwent Tc-TF SPECT and CT of head and neck to differentiate recurrent or residual NPC from benign lesions. Histopathologic examinations were performed on nasopharyngeal biopsies of all 36 patients. RESULTS Based on the biopsy results, the sensitivity, specificity, and accuracy of Tc-TF SPECT were 64%, 96%, and 86%, respectively, for differentiation of recurrent or persistent NPC from benign lesions. For CT and FDG-PET, the sensitivity, specificity, and accuracy were 73%, 88%, and 83% and 100%, 96%, 97%, respectively. For the 27 patients with NPC whose Tc-TF SPECT and CT results were congruent, the combination of Tc-TF SPECT and CT had the same sensitivity, specificity, and accuracy (100%, 96%, and 96%) as FDG-PET. For the nine patients with NPC with incongruent Tc-TF SPECT and CT results, FDG-PET correctly differentiated two benign lesions from seven recurrent/residual NPCs. CONCLUSIONS Although, FDG-PET is the best tool for detecting recurrent or residual NPC, combined congruent Tc-TF SPECT and CT results achieved the same accuracy as FDG-PET. Therefore, we concluded that FDG-PET could be considered only when Tc-TF SPECT and CT give incongruent results. Cancer 2001;92:434–9. © 2001 American Cancer Society.

This study recalibrates corporate bond idiosyncratic risks in an international context. Applying a statistically powerful risk decomposition scheme, we show in this study that diversification is improved by the addition of a global risk benchmark. We build a long-run stationary yield spread decomposition scheme which provides better diversification effect. In addition to global liquidity and default risk factors, we also include country-specific default risk component, and all of them are free of measurement or availability issues. The idiosyncratic risk component is estimated as a fixed effect along with all the parameter estimates, rather than separately from an exogenous generating process. Our linear model is simple, yet it can be easily and promptly applied by practitioners.

The purpose of this study was to evaluate the accuracy of 18F-FDG PET/CT scans in detecting adrenal metastasis in liver transplant candidates with hepatocellular carcinoma (HCC). A total of 166 patients diagnosed with HCC received 18F-FDG PET/CT imaging before liver transplantation. Of these patients, 5 patients (4 males, 1 female; median age: 51.2 y, range: 33-61 y) were found to have suspected adrenal metastases and were included in this study. Two cases (Cases 1 and 5) underwent an 18F-FDG PET/CT scan at the initial stage, 3 cases (Cases 2-4) underwent an 18F-FDG PET/CT scan for restaging, and one case (Case 5) underwent a second 18F-FDG PET/CT scan for evaluating treatment response. Among the 8 lesions, there was one false-negative metastatic lesion (Lesion 4, Case 3) and one false-positive adrenal gland lesion (Lesion 7, Case 5) when compared with either histopathologic reports or established clinical and imaging follow-up results. In general, 18F-FDG PET/CT scans have limitations that make it difficult to distinguish between malignant and benign lesions in adrenal glands that are based only on quantitative values measured using the 18F-FDG PET/CT scan.

Early detection of regional cerebral anomalies in acute carbon monoxide (CO) poisoning by (99m)Tc-hexamethylprophylene amine oxime (HMPAO) brain single photon emission computed tomography (SPECT) imaging has been reported previously. However, SPECT findings varied in these studies because of their small population sizes. In this study, we included 96 patients with acute CO intoxication and analyzed the regional perfusion changes in these patients by means of HMPAO brain SPECT.Ninety-six patients, aged 4-80 years (mean age 32 years) with acute CO intoxication diagnosed by our emergency department were included in this study. Exclusion criteria included previous cerebrovascular diseases, brain injury, brain surgery and any known neurological and psychological disorders. All patients underwent a brain scan using a dual-head camera and fan-beam collimator 90-120 min after injection of (99m)Tc-HMPAO. Brain SPECT images were obtained for interpretation.Our data suggested that 79 of the 96 patients (82.3 %) had abnormal HMPAO brain images. The predominant site of disease was basal ganglia (52/96 = 54.2 %), followed by temporal lobe (48/96 = 50.0 %), parietal lobe (44/96 = 45.8 %), frontal lobe (30/96 = 31.2 %), occipital lobe (21/96 = 21.9 %) and thalamus (8/96 = 8.3 %). No patients with acute CO intoxication had perfusion abnormalities in the cerebellum. In addition, there was no significant difference in serum COHb levels between patients with abnormal and normal HMPAO brain images.(99m)Tc-HMPAO SPECT imaging is a useful tool to detect functional brain injury in acute CO intoxication.

We attempt to identify in this paper the role of trading noise as a transactions cost to market participant in the sense of Stoll (2000), especially in the presence of trading concentration. Applying the measures of Hu (2006) and Kang and Yeo (2008), we analyze the noise proportion in intraday stock returns and its interaction with investor herding and search cost. Although this noise is high on individual orders and low on institutional orders, its behavior at market open is entirely different from the rest of the day. Noises for small cap stocks, unlike volatilities, are lower than those for large cap stocks. We also found that noise relates positively to trading volume, but inversely to holdings and turnover ratio of institutional investors. Responses from institutional and individuals are quite the opposite. The noise proportion generated by individual order rises with institutional turnover and search cost encountered, while that of institutional order behaves just oppositely. At market open, behaviors of noise from institutional and individual orders just switch mutually, and then switch back afterwards. Also, noise from high-cap stocks is actually more responsive than that from low-cap ones across investors. So trading noise is a specific transactions cost, prominent to only certain investors, at certain time and for certain stocks in the market, rather than a general market friction as argued in Stoll (2000). This transactions cost is inversely related to search costs encountered in trading, which depends on investor, trading hour of day and market capitalization of stocks.

We explore in this paper how trading noise, when considered as a market friction, reacts to trading activity. Transactions cost is a good explanation for intraday trading behavior in the market according to our data. Particularly, we show that in general trading brings friction to market. However, trading friction at market open is the lowest during the day, as trading causes less friction then relatively. This is due to the behavioral difference among investors. When market opens, individual trading removes, while institutional trading brings, market friction. Situation in the rest of the day is just the opposite, where individual, instead of institutional, trading brings friction. The uneven behavior of trading noise across investors and time of day makes it a specific, rather than general, transactions cost, as opposed to Stoll (2000). Intraday trading activity suppresses both order width and depth, as proxies for trading intensity, therefore creates more noise or friction in the market. Width and depth contribute to trading noise in a polarized way, so that individual trading hurts friction in small cap stocks at open, but benefits it at close. Institutional trading brings extremely strong friction to large cap stocks, but less so at market close. So trading noise as a specific, rather than general, transactions cost is prominent only to certain investors, at certain time and for certain stocks in the market. Our findings lend itself to the justification of the new financial transactions tax proposed by the European Union.

We analyze in this study cause of herding in a stock market. Information cascades have often been considered as a primary choice. However, we propose alternative explanations in this study. Employing intraday order book data, we suggest including an alternative theory based on search cost of investors, in addition to the information cascade argument. Specifically, previous works used data with daily or lower frequency based on a herding measure of Lakonishok, Shleifer, and Vishny (1992). We adopt instead a measure by Patterson and Sharma (2006) and argue that the search model of Vayanos and Wang (2007) characterizes herding phenomenon better, especially at market open. Our analysis is also consistent with the information competition equilibrium of Back, Cao and Willard (2000) and dynamic friction model of Hu (2006). We find that stronger order flow herding takes place when buyers and sellers are 6 times higher as well as when buyer-seller ratio is 50% higher, and is driven by lower transactions cost and shorter order-filling time. Herding tends to occur in trading of high-cap, high turnover stocks, which contradicts prediction of the information cascade hypothesis. Search cost effect is stronger at market open, while information cascade effect is stronger at market close. Therefore our study suggests that herding should be related both to intrinsic search cost structure of investors as well as information related factors.

The possibility of a coincidental appearance of hyperparathyroidism and thyroid cancer is not often considered because of its low incidence. Here, we present a case of a 49-year-old woman with a parathyroid adenoma coexisting with two sites of papillary thyroid carcinoma. Dual-phase 99m Tc-methoxyisobutylisonitrile (MIBI) parathyroid imaging before the operation correctly visualized the site of the parathyroid adenoma. In addition, two papillary thyroid carcinomas showed faint uptake of 99m Tc-MIBI on delayed image. Total thyroidectomy and parathyroidectomy of a solitary parathyroid adenoma were performed. The patient subsequently underwent radioiodine-131 ablation and was treated with T4 suppression. This case illustrates the need for clinical awareness of concomitant hyperparathyroidism and thyroid cancer. Dual-phase 99m Tc-MIBI parathyroid imaging may be useful for detecting indolent thyroid cancer before it becomes a distinct disease.

Information asymmetry and liquidity concentration has been widely discussed in literatures. This study shows how liquidity influences not only forecasting performances of term structure estimation, but also information transmission and price adjustment across markets. Our analysis helps understanding how extreme market movements affect one another. This study examines, and provides a rationale for incorporating, liquidity in estimating term structure. Forecasting performance can be greatly enhanced when conditioning on trading liquidity. It reduces information asymmetry in the sense of Easley and O’Hara (2004) and Burlacu, Fontaine and Jimenez-Garces (2007). We adopt a time series forecasting model following Diebold and Li (2006) to compare behavior of forecasted price errors. Our findings indicate that forecasted price errors in markets with less depth would influence those with more. Information asymmetry induces volatile trading first and then price adjustment is transmitted to another market due to insufficient market depth. Cross-market price adjustment could be as much as 21 bps on average. Compared with previous studies, our results establish a valid reason to condition on liquidity when forecasting prices.

The publisher regrets that this is an accidental duplication of an article that has already been published in The Breast, 12 (2003) 58-62, doi:10.1016/S0960-9776(02)00136-4. The duplicate article has therefore been withdrawn.

Purpose: Several studies have reported significant renal toxicity after the use of a high dose of90Y-DOTATOC. Thus, renal protection is necessary in treatments with90Y-DOTA Tyr3-octroetide (DOTATOC). The infusion of certain positively charged amino acids has been shown to effectively reduce renal uptake of DOTATOC. In this study, we compared the effectiveness of three kinds of amino acids, D-lysine (lysine),L-arginine (arginine) and histidine, on renal protection in healthy rats and tried to determine which one was the most effective.Methods: Twenty SD healthy male rats were divided into 4 groups: lysine, histidine, arginine, and control. The rats were injected with a dose of 400 mg/kg of amono acid or 2 ml of phosphate-buffered saline (PBS) (as control) intraperitoneally. All rats were sacrificed at 4 hrs after the injection of 1 MBq111In-DOTATOC. Samples of the kidney were taken and weighed carefully. The counts of radioactivity were measured by a gamma counter and renal concentrations were calculated and expressed as percent injected dose per gram (% ID/g).Results: The renal uptake of111In-DOTATOC was significantly lower for all three kinds of amino acids when compared to the control group. The renal uptake of111In-DOTATOC in the lysine group was significantly lower than those in the histidine and arginine groups. The renal uptake of111In-DOTATOC in the histidine group was lower than that in the arginine group, but no statistical difference was noted.Conclusion: Among these three amino acids, lysine had the best reduction rate of renal uptake of DOTATOC. Histidine was more effective than arginine but no statistical difference was noted.

Objectives. Systemic lupus erythematosus (SLE) can affect multiple organs. Coronary artery disease has received increasing recognition as a major cause of morbidity and mortality in SLE in recent years. The purpose of this study was to evaluate the utility of technetium-99m sestamibi single-photon emission computed tomography ( 99m Tc-sestamibi SPECT) in the detection of cardiovascular involvement in SLE patients with non-specific clinical chest symptoms such as chest discomfort and or dyspnoea and or occasional palpitation. Methods. Thirty-three SLE female patients (age range: 22 45 yr) with non-specific complaints such as chest discomfort and or dyspnoea and or occasional palpitation were investigated using a 99m Tc-sestamibi myocardial perfusion SPECT scan at rest and after dipyridamole infusion in a stress study. The age- and sex-matched healthy group (24 cases) and SLE patients without any cardiovascular symptoms/signs (28 cases) were also included as controls in this study. The results of the uptake pattern of 99m Tc-sestamibi were classified into four types including normal. persistent perfusion defect, reversible perfusion defect and reverse redistribution. Results. Perfusion abnormalities were detected in 27 cases (seven patients had persistent perfusion defects, 15 patients had reversible perfusion defects, one patient had both persistent and reversible perfusion defects, two patients showed a reverse redistribution pattern and two patients had both reversible perfusion defects and a reverse redistribution pattern). The results of the SPECT in the healthy group were all normal. However, perfusion abnormalities were detected in 12 cases in the group of asymptomatic SLE patients. Conclusions. 99m Tc-sestamibi myocardial perfusion SPECT is a useful non-invasive imaging modality to detect cardiovascular involvement in SLE patients with non-specific clinical complaints of heart disease.

In type 2 diabetes, a high prevalence of oral problems has been detected. These problems include mouth dryness, an increase in periodontal disease, oral Candida , and swelling of the parotid glands (1). Salivary flow rates have often been found to be significantly reduced in type 2 diabetic patients (2), although these findings have not been confirmed (3). Scintigraphic changes correlate well with salivary gland abnormalities (4) and histopathological changes (5). This technique has gained widespread acceptance in evaluating a variety of salivary glandular disorders (6,7). The aim of the present study was to test whether patients with type 2 diabetes suffer from impaired salivary function using objective and quantitative salivary scintigraphy. A total of 40 patients with type 2 diabetes for 10 years and 36 healthy age- and sex-matched …