Acute myocarditis mimicking ST-elevation myocardial infarction: A diagnostic challenge for frontline clinicians

The clinical presentation of acute myocarditis is highly variable ranging from no symptoms to cardiogenic shock. Despite considerable progress, it remains a challenge for frontline physicians to discriminate between acute myocarditis and myocardial infarction, especially in the early phase. Our case serves as a reminder that acute presentation of myocarditis could resemble ST elevation myocardial infarction potentially misdirecting the therapeutic decision. The clinical presentation, electrocardiographic and laboratory findings of the patient are not specific enough to distinguish acute myocarditis from myocardial infarction. The gold standard tests such coronary angiography and cardiovascular magnetic resonance (CMR) can reliably differentiate the two entities.

Ultrahigh-resolution optical coherence tomography/angiography with an economic and compact supercontinuum laser

In this study, a Q-switch pumped supercontinuum laser (QS-SCL) is used as a light source for in vivo imaging via ultrahigh-resolution optical coherence tomography and angiography (UHR-OCT/OCTA). For this purpose, an OCT system based on a spectral-domain detection scheme is constructed, and a spectrometer with a spectral range of 635 - 875 nm is designed. The effective full-width at half maximum of spectrum covers 150 nm, and the corresponding axial and transverse resolutions are 2 and 10 µm in air, respectively. The relative intensity noise of the QS-SCL and mode-locked SCL is quantitatively compared. Furthermore, a special processing algorithm is developed to eliminate the intrinsic noise of QS-SCL. This work demonstrates that QS-SCLs can effectively reduce the cost and size of UHR-OCT/OCTA instruments, making clinical applications feasible.

3052Non-vitamin K antagonist oral anticoagulants are safe and effective alternatives to warfarin across subgroups by renal function: results from Danish registries

Background

All non-vitamin K antagonist oral anticoagulants (NOACs) have some degree of renal excretion, and patients with severely reduced renal function have been excluded from randomized controlled clinical trials of stroke prevention in atrial fibrillation (AF). Influence of renal function on outcomes has not been assessed in previous real-world studies of NOACs in AF.

Purpose

To assess influence of renal function on efficacy and safety of dabigatran, rivaroxaban or apixaban vs. warfarin.

Methods

Using nationwide registries, we identified all Danish AF patients who initiated warfarin, dabigatran, rivaroxaban or apixaban between 2012 and 2016. We included patients with a plasma creatinine measurement within 14 days from drug initiation and calculated estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Hazard ratio (HR) of stroke/thromboembolism (TE) or major bleeding according to oral anticoagulation was calculated using multivariable-adjusted Cox regression analyses with warfarin as reference.

Results

We included 14,673 AF patients who started first-time oral anticoagulation within 14 days from AF diagnosis, and our study population comprised 2482 (16.9%) initiators of dabigatran (median age 72, 44.5% women), 3806 (25.9%) initiators of rivaroxaban (median age 75, 48.0% women), 5067 (34.5%) initiators of apixaban (median age 76, 48.8% women), and 3318 (22.6%) initiators of warfarin (median age 75, 45.4% women). eGFR was >50, 30–50 and 15 to <30 mL/min/1.73m2 in 10,281 (83.1%), 2079 (14.2%) and 404 (2.8%) patients at baseline. After adjustment for age, sex, year of inclusion, income, cohabitation status, eGFR, hemoglobin, medications and comorbidities, the HRs for stroke/TE compared to warfarin were 0.94 (95% confidence interval (CI) 0.74–1.20) for dabigatran, 1.06 (CI 0.84–1.34) for rivaroxaban, and 1.10 (CI 0.88–1.36) for apixaban. There were no significant heterogeneities in HRs of stroke/TE across subgroups by eGFR. Apixaban (HR 0.74, CI 0.62–0.89) was associated with lower risk of major bleeding compared to warfarin, rivaroxaban (HR 1.06, CI 0.88–1.27) with risk of major bleeding comparable to warfarin, and there were no significant heterogeneities in risk of major bleeding with rivaroxaban or apixaban across subgroups by eGFR. Dabigatran was associated with lower risk of bleeding among patients with eGFR >50 mL/min/1.73m2, but not among patients with eGFR 30–50 mL/min/1.73m2 (interaction P=0.03).

Conclusions

In a large real-world cohort, renal function had no significant influence on efficacy or safety of apixaban or rivaroxaban when compared with warfarin. Dabigatran was associated with lower risk of bleeding among patients with normal or mildly decreased renal function, but not among patients with moderately decreased renal function.

Acknowledgement/Funding

This study was funded by an unrestricted grant from the Capital Region of Denmark, Foundation for Health Research.

P4779High facility preference for rivaroxaban in atrial fibrillation increases risk of major bleeding compared to facility preference for apixaban

Background

No randomized trial has compared efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOACs) in atrial fibrillation (AF). Previous real-world comparisons could be biased by patient characteristics of importance for treatment selection, but instrumental variables could potentially account for measured and unmeasured confounders.

Purpose

To compare efficacy and safety of rivaroxaban and apixaban using facility preference for type of NOAC as instrumental variable.

Methods

AF patients started on apixaban or rivaroxaban were identified using nationwide registries. We categorized patients according to facility preference for type of NOAC, measured as percentage of the prior 20 AF patients started on rivaroxaban in the same facility. Occurrence of stroke/thromboembolism (TE), major bleeding, myocardial infarction and all-cause mortality during two years of follow-up were investigated using adjusted Cox regressions. To further examine general frailty according to facility preferences we also investigated occurrence of cancer, urogenital tract infection, dehydration and fracture.

Results

We analyzed 6264 AF patients initiated on rivaroxaban or apixaban. Compared with patients treated in facilities that used rivaroxaban in 0–20% of cases, the adjusted hazard ratio for bleeding was 1.05 when treated in a facility with 25–40% use; 1.40 with 45–60% use; 1.50 with 65–80% use; and 1.81 for 85–100% use (Ptrend=0.002). Higher facility level use of rivaroxaban was not associated with increased risk of stroke/TE (Ptrend=0.06), myocardial infarction (Ptrend=0.87) or all-cause mortality (Ptrend=0.91), and there was no association between facility preference for rivaroxaban and risk of cancer (Ptrend=0.83), urogenital tract infection (Ptrend=0.49), dehydration (Ptrend=0.91) or fracture (Ptrend=0.47).

Characteristics by facility preference Percent of previous AF patients from facility started on rivaroxaban P for trend 0–20% 25–40% 45–60% 65–80% 85–100% No. of patients 1406 1421 1551 930 956 Received rivaroxaban, (%) 279, (19.8) 499, (35.1) 711, (45.8) 632, (68.0) 774, (81.0) <0.001 Standard dose, (%) 1216, (86.5) 1232, (86.7%) 1366, (88.1%) 793, (85.3%) 824, (86.2%) 0.62 Median age, (interquartile range) 70, (63.3–74) 69, (63–74) 70, (64–74) 70, (64–75) 70, (63–75) 0.11 Below median income, (%) 740, (52.6) 699, (49.2) 764, (49.3) 458, (49.3) 471, (49.3) 0.31 Prior stroke, (%) 99, (7.0) 115, (8.1) 134, (8.6) 69, (7.4) 74, (7.7) 0.56 Prior bleeding, (%) 136, (9.7) 141, (9.9) 163, (10.5) 91, (9.8) 97, (10.1) 0.51 Antiplatelet therapy, (%) 445, (31.7) 465, (32.7) 491, (31.7) 303, (32.6) 317, (33.2) 0.49

Rate of events according to instrument

Conclusion

High facility preference for rivaroxaban increases risk of major bleeding compared to facility preference for apixaban.

Acknowledgement/Funding

This study was funded by an unrestricted grant from the Capital Region of Denmark, Foundation for Health Research.

Deep ocean minerals inhibit IL-6 and IGFIIR hypertrophic signaling pathways to attenuate diabetes-induced hypertrophy in rat hearts

We previously reported that deep sea water (DSW) prolongs the life span of streptozotocin (STZ)-induced diabetic rats by the compensatory augmentation of the insulin like growth factor (IGF)-I survival signaling and inhibition of apoptosis. Here, we investigated the effects of DSW on cardiac hypertrophy in diabetic rats. Cardiac hypertrophy was induced in rats by using STZ (65 mg/kg) administered via IP injection. DSW was prepared by mixing DSW mineral extracts and desalinated water. Different dosages of DSW-1X (equivalent to 37 mg Mg²⁺·kg^-1·day^-1), 2X (equivalent to 74 mg Mg²⁺·kg^-1·day^-1) and 3X (equivalent to 111 mg Mg²⁺·kg^-1·day^-1) were administered to the rats through gavage for 4 wk. Cardiac hypertrophy was evaluated by the heart weight-to-body weight ratio and the cardiac tissue cross-sectional area after hematoxylin and eosin staining. The protein levels of the cardiac hypertrophy signaling molecules were determined by Western blot. Our results showed that the suppressive effects of the DSW treatment on STZ-induced cardiac hypertrophy were comparable to those of MgSO₄ administration and that the hypertrophic marker brain natriuretic peptide (BNP) was decreased by DSW. In addition, DSW attenuated both the eccentric hypertrophy signaling pathway, IL-6-MEK-STAT3, and the concentric signaling pathway, IGF-II-PKCα-CaMKII, in DM rat hearts. The cardiac hypertrophy-associated activation of extracellular signal-regulated kinase (ERK) and the upregulation of the transcription factor GATA binding protein 4 (GATA4) were also negated by treatment with DSW. The results from this study suggest that DSW could be a potential therapeutic agent for the prevention and treatment of diabetic cardiac hypertrophy.NEW & NOTEWORTHY Deep sea water, containing high levels of minerals, improve cardiac hypertrophy in diabetic rats through attenuating the eccentric signaling pathway, IL-6-MEK5-STAT3, and concentric signaling pathway, IGF2-PKCα-CaMKII. The results from this study suggest that deep sea water could be a potential therapeutic agent for the prevention and treatment of diabetic cardiac hypertrophy.

Hyperprogressive disease during PD-1/PD-L1 blockade in patients with non-small-cell lung cancer

BACKGROUND

Immune checkpoint blockade with Programmed cell death 1 (PD-1)/PD-L1 inhibitors has been effective in various malignancies and is considered as a standard treatment modality for patients with non-small-cell lung cancer (NSCLC). However, emerging evidence show that PD-1/PD-L1 blockade can lead to hyperprogressive disease (HPD), a flair-up of tumor growth linked to dismal prognosis. This study aimed to evaluate the incidence of HPD and identify the determinants associated with HPD in patients with NSCLC treated with PD-1/PD-L1 blockade.

PATIENTS AND METHODS

We enrolled patients with recurrent and/or metastatic NSCLC treated with PD-1/PD-L1 inhibitors between April 2014 and November 2018. Clinicopathologic variables, dynamics of tumor growth, and treatment outcomes were analyzed in patients with NSCLC who received PD-1/PD-L1 blockade. HPD was defined according to tumor growth kinetics (TGK), tumor growth rate (TGR), and time to treatment failure (TTF). Immunophenotyping of peripheral blood CD8+ T lymphocytes was conducted to explore the potential predictive biomarkers of HPD.

RESULTS

A total of 263 patients were analyzed. HPD was observed in 55 (20.9%), 54 (20.5%), and 98 (37.3%) patients according to the TGK, TGR, and TTF. HPD meeting both TGK and TGR criteria was associated with worse progression-free survival [hazard ratio (HR) 4.619; 95% confidence interval (CI) 2.868-7.440] and overall survival (HR, 5.079; 95% CI, 3.136-8.226) than progressive disease without HPD. There were no clinicopathologic variables specific for HPD. In the exploratory biomarker analysis with peripheral blood CD8+ T lymphocytes, a lower frequency of effector/memory subsets (CCR7-CD45RA- T cells among the total CD8+ T cells) and a higher frequency of severely exhausted populations (TIGIT+ T cells among PD-1+CD8+ T cells) were associated with HPD and inferior survival rate.

CONCLUSION

HPD is common in NSCLC patients treated with PD-1/PD-L1 inhibitors. Biomarkers derived from rationally designed analysis may successfully predict HPD and worse outcomes, meriting further investigation of HPD.

Molecular detection of Haemophilus parasuis serotypes 4, 5 or 12 and 13 in Peninsular Malaysia

Although the economic importance of Haemophilus parasuis infection causing Glasser's disease is prevalent throughout pig farms in Peninsular Malaysia, there is a dearth of knowledge on its actual nature. In this study, a multiplex PCR was performed to screen for three major predominant virulent strains of H. parasuis, which are serotypes 4, 5 or 12 and 13. A total of 175 tissues or bodily fluid samples of various parts were collected from diseased animals from October, 2016 to February, 2018; with total of 62.9% positive detection of H. parasuis. The highest detection was found to be in the pericardial sac fibrin (90.9%) followed by pleural fibrin, lung, pleural fluid, tonsil, pericardial sac, peritoneal fluid, abdominal fibrin, joint fluid, brain and pericardium. Serotype 13 was the highest (40/110) followed by serotype 4(37/110), serotype 5(31/110) and 12 samples were nontypable (12/110). The presence of untypable serotype also drives to further identification of other serotypes in Malaysia.

Multiple supply chain adoption under uncertainty

Purpose

The spatial and psychological distance within agri-food chains provides both profit and risk for supply chain members. Grounded on the transaction cost economics (TCE) and institutional theory (IT), the purpose of this paper is to test whether the adoption of multiple supply chains (MSCs), which adopt both traditional and shortened supply chains, can be used to manage uncertainty and mitigate the risk associated with a supply chain.

Design/methodology/approach

In order to test the hypothesis, matched questionnaire surveys were developed to collect the data from farm managers and consumers. Completed questionnaires were received from 112 respondents. The hierarchical regression analysis was performed to test hypotheses.

Findings

The result shows the positive effects of environmental and behavioral uncertainties on MSC adoption and represents the diminished moderating effects of institutions (industrial and consumption tendency) on the relationship between uncertainties and MSA adoption.

Research limitations/implications

This study only explored producers and their recommended consumers; future studies can undertake questionnaire designs (one producer-to-many consumers) and empirical analyses with analytic hierarchy process theory to reexamine the hypotheses proposed in this study.

Practical implications

MSC adoption is a way to manage uncertainties resulting from spatial and psychological distance in the supply chain. Producers and consumers show their risk preferences by SC adoption after considering pre-constructed societal norms. Therefore, the consumers’ and producers’ choice of a supply chain reflects a process of communicating risk. The adoption of a mixed governance mode (MSC adoption) and accessing information about common practices are two ways to decrease such uncertainties.

Social implications

There are multiple goals (traceability, fairness, efficiency, well-being) in the food supply chain that may be satisfied by MSC adoption. Therefore, policymakers should understand the different values of various supply chains and facilitate the development of various supply chain modes.

Originality/value

This study integrated the undersocialized and oversocialized perspectives (TCE and IT) to understand how uncertainties of supply chains may be diminished. Based on these perspectives, it found that the adoption of the mixed governance mode and accessing of institutional information are two ways to decrease such uncertainties.

Diagnostic value of electrocardiogram in cardiac tamponade

INTRODUCTION

We aim to study the diagnostic value of electrocardiogram (ECG) in cardiac tamponade.

METHODS

This study was a single centre, retrospective casecontrol study. We recruited 42 patients diagnosed with cardiac tamponade of various aetiologies confirmed by transthoracic echocardiography and 100 controls between January 2011 and December 2015. The ECG criteria of cardiac tamponade we adopted was as follows: 1) Low QRS voltage in a) the limb leads alone, b) in the precordial leads alone or, c) in all leads, 2) PR segment depression, 3) Electrical alternans, and 4) Sinus tachycardia.

RESULTS

Malignancy was the most common causes of cardiac tamponade, the two groups were of similar proportion of gender and ethnicity. We calculated the sensitivity (SN), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) of each ECG criteria. Among the ECG abnormalities, we noted the SN of 'low voltage in all chest leads' (69%), 'low voltage in all limb leads' (67%) and 'sinus tachycardia' (69%) were higher as compared to 'PR depression' (12%) and 'electrical alternan' (5%). On the other hand, 'low voltage in all chest leads' (98%), 'low voltage in all leads' (99%), 'PR depression' (100%) and 'electrical alternans' (100%) has highest SP.

CONCLUSION

Our study reaffirmed the findings of previous studies that electrocardiography cannot be used as a screening tool for diagnosing cardiac tamponade due to its low sensitivity. However, with clinical correlation, electrocardiography is a valuable adjuvant test to 'rule in' cardiac tamponade because of its high specificity.

Multilayered gene control drives timely exit from the stem cell state in uncommitted progenitors during Drosophila asymmetric neural stem cell division

Self-renewal genes maintain stem cells in an undifferentiated state by preventing the commitment to differentiate. Robust inactivation of self-renewal gene activity following asymmetric stem cell division allows uncommitted stem cell progeny to exit from an undifferentiated state and initiate the commitment to differentiate. Nonetheless, how self-renewal gene activity at mRNA and protein levels becomes synchronously terminated in uncommitted stem cell progeny is unclear. We demonstrate that a multilayered gene regulation system terminates self-renewal gene activity at all levels in uncommitted stem cell progeny in the fly neural stem cell lineage. We found that the RNA-binding protein Brain tumor (Brat) targets the transcripts of a self-renewal gene, deadpan (dpn), for decay by recruiting the deadenylation machinery to the 3' untranslated region (UTR). Furthermore, we identified a nuclear protein, Insensible, that complements Cullin-mediated proteolysis to robustly inactivate Dpn activity by limiting the level of active Dpn through protein sequestration. The synergy between post-transcriptional and transcriptional control of self-renewal genes drives timely exit from the stem cell state in uncommitted progenitors. Our proposed multilayered gene regulation system could be broadly applicable to the control of exit from stemness in all stem cell lineages.

Hiring decisions on certified manpower

Purpose

The industry-wide adoption of a novel practice is often considered to be an institutional change. Although research on institutionalization has been accumulating, how and why embedded actors in the field become motivated to embrace change that remains sidelined. Viewing the introduction of a new human resource management practice, the recruitment of non-compulsory certified manpower, which is still in its infancy in the service sector of Taiwan, as a new institution, the purpose of this paper is to identify the distinct motives behind firms’ hiring decisions, and examine the extent to which such hiring decisions are contingent on institutional conditions and firm attributes.

Design/methodology/approach

The data used to test the hypotheses were drawn from a survey on service firms in Taiwan in the second half of 2011. Hypotheses were examined through moderated hierarchical regression analyses in a sample of 254 Taiwanese service firms across major sectors.

Findings

Integrating the resource dependency and social contagion views, the study contends that resource scarcity drives, or legitimacy enables, service firms to deviate from traditional hiring patterns and instead adopt new preferences toward certified manpower. The study not only shows that social factors should be incorporated into the diffusion of a new HR recruitment practice in the service sector, which is traditionally based upon economic considerations, but also sheds light on the context-dependent nature of the process of institutional innovation.

Originality/value

This study is an attempt not only to test a dual-theoretical model on the extent to which a service firm’s new hiring pattern is influenced by two distinct types of motivation, but also to evidence how an institutional innovation, in terms of the regime of service manpower certification, takes root and spreads in the field. The managerially discretional account of the resource dependence theory needs to be reconciled with social contagion theory, which highlights the influence of collective actions and so provides a better understanding of the diffusion of new HR recruitment practices in the service industry.

Do Innovation Efficiency and Powerful Leadership Affect the Performance Effect of Technological Diversification?

Considering that technological diversification is rooted in distinct technological knowledge that usually comes from different business units, a firm’s practices that can improve efficiency in integrating and exploiting this knowledge may be key potential moderators in this focal relationship. Based on a sample of 3,277 firm-year observations of 435 firms in Taiwanese information and communication technology sectors during the 2004-2014 period, this study finds that technological diversification has an inverted U-shaped relationship with performance. Such relationship also can be moderated by high levels of innovation efficiency and CEO power. These findings caution against drawing universalistic normative implications for pursuing technological diversification.

Immunohistochemical and molecular analysis of spitzoid neoplasms with pulverocyte subclones

BACKGROUND

Clonal naevi are characterized by a focal proliferation of pigmented melanocytes in an otherwise banal naevus. These subclones are often composed of aggregates of larger, epithelioid melanocytes with nuclear atypia and dusty-grey cytoplasmic pigmentation, which are referred to as 'pulverocytes', and this finding may lead to a misdiagnosis of malignant melanoma (MM).

AIM

To characterize the significance of subclones of dusty-grey pigmented epithelioid melanocytes within spitzoid neoplasms.

METHODS

We studied the histological and molecular features of a series of 20 spitzoid neoplasms with pulverocyte subclones encountered in our practice, including both atypical Spitz tumours (ASTs) and invasive MMs.

RESULTS

Pulverocytes were predominantly dermal, and the percentage of subclones ranged from 2% to 40%, with a median of 10% in ASTs and 25% in lesions we classified as MM. In cases with > 10% subclones, there was an increased odds of fluorescence in situ hybridization positivity (OR = 12; 95% CI 1.2-293.4; P = 0.03) and an increased odds of homozygous 9p21 deletion (OR = 3.6; 95 CI 0.28-89.82; P = 0.33), although the latter did not reach statistical significance.

CONCLUSIONS

We consider spitzoid lesions with a small subclone population to be a variant of a clonal naevus with indolent behaviour, whereas lesions with larger pulverocyte populations are more likely to have chromosomal copy number aberrations and in some cases may represent malignant transformation.

Co-clinical trials demonstrate predictive biomarkers for dovitinib, an FGFR inhibitor, in lung squamous cell carcinoma

Background

We conducted co-clinical trials in patient-derived xenograft (PDX) models to identify predictive biomarkers for the multikinase inhibitor dovitinib in lung squamous cell carcinoma (LSCC).

Methods

The PDX01-02 were established from LSCC patients enrolled in the phase II trial of dovitinib (NCT01861197) and PDX03-05 were established from LSCC patients receiving surgery. These five PDX tumors were subjected to in vivo test of dovitinib efficacy, whole exome sequencing and gene expression profiling.

Results

The PDX tumors recapitulate histopathological properties and maintain genomic characteristics of originating tumors. Concordant with clinical outcomes of the trial enrolled-LSCC patients, dovitinib produced substantial tumor regression in PDX-01 and PDX-05, whereas it resulted in tumor progression in PDX-02. PDX-03 and -04 also displayed poor antitumor efficacy to dovitinib. Mutational and genome-wide copy number profiles revealed no correlation between genomic alterations of FGFR1-3 and sensitivity to dovitinib. Of note, gene expression profiles revealed differentially expressed genes including FGF3 and FGF19 between PDX-01 and 05 and PDX-02-04. Pathway analysis identified two FGFR signaling-related gene sets, FGFR ligand binding/activation and SHC-mediated cascade pathway were substantially up-regulated in PDX-01 and 05, compared with PDX-02-04. The comparison of gene expression profiles between dovitinib-sensitive versus -resistant lung cancer cell lines in the Cancer Cell Line Encyclopedia database also found that transcriptional activation of 18 key signaling components in FGFR pathways can predict the sensitivity to dovitinib both in cell lines and PDX tumors. These results highlight FGFR pathway activation as a key molecular determinant for sensitivity to dovitinib.

Conclusions

FGFR gene expression signatures are predictors for the response to dovitinib in LSCC.

Noninvasive structural and microvascular anatomy of oral mucosae using handheld optical coherence tomography

In this study, we demonstrated the feasibility of using a handheld optical coherence tomography (OCT) for in vivo visualizations of the microstructural and microvascular features of various oral mucosal types. To scan arbitrary locations of the oral mucosa, a scanning probe was developed, composed of a probe body fabricated by a 3D printer, miniaturized two-axis galvanometer, relay lenses, and reflective prism. With a 3D printing technique, the probe weight and the system volume were greatly reduced, enabling the effective improvement of imaging artifacts from unconscious motion and system complexity. Additionally, in our design, the distal end of the probe can be switched to fit various oral conditions, and the optical parameters of the probe, such as the transverse resolution, working distance, and probe length can be easily varied. The results showed that the epithelium and lamina propria layers, as well as the fungiform papilla and salivary gland, were differentiated. Moreover, various microcirculation features at different mucosal sites were identified that are potentially effective indicators for the diagnosis of premalignant lesions. The demonstrated results indicate that the developed OCT system is a promising tool for noninvasive imaging of oral mucosae.

RBPJ/CBF1 interacts with L3MBTL3/MBT1 to promote repression of Notch signaling via histone demethylase KDM1A/LSD1

Notch signaling is an evolutionarily conserved signal transduction pathway that is essential for metazoan development. Upon ligand binding, the Notch intracellular domain (NOTCH ICD) translocates into the nucleus and forms a complex with the transcription factor RBPJ (also known as CBF1 or CSL) to activate expression of Notch target genes. In the absence of a Notch signal, RBPJ acts as a transcriptional repressor. Using a proteomic approach, we identified L3MBTL3 (also known as MBT1) as a novel RBPJ interactor. L3MBTL3 competes with NOTCH ICD for binding to RBPJ. In the absence of NOTCH ICD, RBPJ recruits L3MBTL3 and the histone demethylase KDM1A (also known as LSD1) to the enhancers of Notch target genes, leading to H3K4me2 demethylation and to transcriptional repression. Importantly, in vivo analyses of the homologs of RBPJ and L3MBTL3 in Drosophila melanogaster and Caenorhabditis elegans demonstrate that the functional link between RBPJ and L3MBTL3 is evolutionarily conserved, thus identifying L3MBTL3 as a universal modulator of Notch signaling in metazoans.

Increased β-catenin accumulation and nuclear translocation are associated with concentric hypertrophy in cardiomyocytes

Defective Wnt/β-Catenin signaling, activated under various pathological conditions, can result in cardiac and vascular abnormalities. In the present study, the possible role of β-catenin over expression during cardiac hypertrophy was investigated. Ten samples from hearts of human patients with acute infarction, and granulation tissue from 20 patients and 10 from normal ones were collected in order to investigate roles of β-catenin in cardiac hypertrophy. H9c2 cardiomyoblast cells and Wistar rat primary neonatal cardiomyocytes were overexpressed with β-catenin. Expression levels of β-catenin protein were increased in human acute infarction tissues and rat hypertension heart tissues. Overexpression of this transcription factor induced actin filament formation and increased hypertrophic marker protein levels via MAPK pathway. In addition, β-catenin overexpression also resulted in increased elevation of NFATc3 and p-GATA4. Therefore, acute infarction resulted in β-catenin overexpression mediated hypertrophy in cardiomyocytes regulated through MAPK pathway.

An Hdac1/Rpd3-Poised Circuit Balances Continual Self-Renewal and Rapid Restriction of Developmental Potential during Asymmetric Stem Cell Division

How the developmental potential of differentiating stem cell progeny becomes rapidly and stably restricted following asymmetric stem cell division is unclear. In the fly larval brain, earmuff (erm) uniquely functions to restrict the developmental potential of intermediate neural progenitors (INPs) generated by asymmetrically dividing neural stem cells (neuroblasts). Here we demonstrate that the histone deacetylase Hdac1/Rpd3 functions together with self-renewal transcriptional repressors to maintain the erm immature INP enhancer in an inactive but poised state in neuroblasts. Within 2 hr of immature INP birth, downregulation of repressor activities alleviates Rpd3-mediated repression on the erm enhancer, enabling acetylation of multiple histone proteins and activating Erm expression. Erm restricts the developmental potential in immature INPs by repressing genes encoding neuroblast transcriptional activators. We propose that poising the fast-activating enhancers of master regulators of differentiation through continual histone deacetylation in stem cells enables self-renewal and rapid restriction of developmental potential following asymmetric division.

Factors influencing the alignment of technological diversification and firm performance

Purpose

Although scholars have paid considerable attention to the relationship between technological diversification and firm performance, research on this relationship has produced mixed findings. To reconcile these inconsistent findings, this study, thus, aims to revisit the performance effect of technological diversification by considering two organizational characteristics as crucial moderators, namely, firm size and financial slack.

Design/methodology/approach

To test the research hypotheses, the research sample covers manufacturing firms in the 2008 Standard & Poor (S&P) 500 index. Data regarding the characteristics and patent information of the sample firms were obtained from Compustat and the US Patent and Trademark Office. The hypotheses were tested by using hierarchical regression models.

Findings

In a sample of 168 S&P 500 manufacturing firms, this study finds that technological diversification has a positive effect on firm performance. The relationship between technological diversification and firm performance is also found to be positively moderated by firm size, financial slack and their configuration.

Originality/value

The findings of this study further suggest that firms should be aware that the effect of technological diversification on performance can be enhanced or hindered in specific contexts.

CEO Overconfidence and Ambidextrous Innovation

While prior research has focused on the effect of CEO overconfidence on innovation, few studies have been conducted to reveal how and whether an overconfident CEO affects ambidextrous innovation, which means the simultaneous and balanced pursuit of both exploratory and exploitative innovation. By observing firms’ patenting behavior, we investigate the effect of CEOs’ psychological attribute of overconfidence on innovation ambidexterity. In addition, we examine how a firm’s governance system moderates the relationship between CEO overconfidence and ambidextrous innovation. The results show that overconfident CEOs are more apt to create or magnify an imbalance in innovation ambidexterity. Furthermore, the results regarding the moderating effects of governance and monitoring mechanisms indicate that an independent board and dedicated institutional ownership mitigate the positive relationship between CEO overconfidence and a firm’s ambidextrous imbalance, while transient institutional ownership enhances this relationship. We also find that analyst following does not effectively monitor an overconfident CEO’s tendency toward an ambidextrous imbalance.

Modelling end-pumped passively Q-switched Nd-doped crystal lasers: manifestation by a Nd:YVO4/Cr4+:YAG system with a concave-convex resonator

A theoretical model for the passively Q-switched (PQS) operation which includes the spatial overlapping between the pump and lasing modes under the thermal lensing effect is developed to give a transcendental equation that can directly determine the critical parameters such as pulse energy, pulse repetition rate, and pulse width for the PQS performance. More importantly, an analytical function which gives the approximate solution for the transcendental equation as well as a specific critical criterion for good PQS operation are derived for practical analyses and design. A Nd:YVO₄/Cr⁴⁺:YAG system with a concave-convex resonator which can achieve fairly stable PQS pulse trains even at a high pump level is further exploited to manifest the proposed spatially dependent model. The good agreement between the experimental results and the theoretical predictions is verified to show the feasibility of the proposed model for designing high-power PQS lasers with high accuracy.

Generation of terahertz optical beating from a simultaneously self-mode-locked Nd:YAG laser at 1064 and 1123 nm

The reflectivity of the output coupler is designed to achieve the synchronously self-mode-locked operation at 1064 and 1123 nm in a diode-end-pumped Nd:YAG laser. Numerical analyses are performed to confirm that the designed output coupler can lead the emission lines to be predominant at 1064 and 1123 nm. Moreover, the crossover of the threshold pump powers for the 1064 and 1123 nm emission lines can be exploited to obtain the single central wavelength of 1064 nm or the single central wavelength of 1123 nm or, simultaneously, dual-central-wavelength self-mode-locked operation by finely adjusting the cavity alignment. For the dual-central-wavelength mode-locked emissions, the pulse repetition rate and the pulse duration are 4.5 GHz and 50.8 ps, respectively. The maximum output power can be up to 2.47 W at a pump power of 7.5 W. The synchronization of the 1064 and 1123 nm mode-locked pulses generates the optical beating pulse trains with repetition rates up to 14.7 THz.

Medicinal herbs Oenanthe javanica (Blume) DC., Casuarina equisetifolia L. and Sorghum bicolor (L.) Moench protect human cells from MPP+ damage via inducing FBXO7 expression

BACKGROUND

The F-box protein 7 (FBXO7) mutations have been identified in families with early-onset parkinsonism and pyramidal tract signs, and designated as PARK15. In addition, FBXO7 mutations were found in typical and young onset Parkinson's disease (PD). Evidence has also shown that FBXO7 plays an important role in the development of dopaminergic neurons and increased stability and overexpression of FBXO7 may be beneficial to PD.

PURPOSE

We screened extracts of medicinal herbs to enhance FBXO7 expression for neuroprotection in MPP⁺-treated cells.

METHODS

Promoter reporter assay in HEK-293 cells was used to examine the cis/trans elements controlling FBXO7 expression and to screen extracts of medicinal herbs enhancing FBXO7 expression. MTT assay was performed to assess cell viability of MPP⁺-treated HEK-293/SH-SY5Y cells. In addition, proteasome activity, mitochondrial membrane potential and FBXO7/TRAF2/GATA2 protein expression were evaluated.

RESULTS

We demonstrated that -202--57 region of the FBXO7 promoter is likely to contain sequences that are bound by positive trans protein factors to activate FBXO7 expression and GATA2 is the main trans protein factor enhancing FBXO7 expression. Extracts of medicinal herbs Oenanthe javanica (Blume) DC. (Umbelliferae), Casuarina equisetifolia L. (Casuarinaceae), and Sorghum bicolor (L.) Moench (Gramineae) improved cell viability of both MPP⁺-treated HEK-293 and SH-SY5Y cells, rescued proteasome activity in MPP⁺-treated HEK-293 cells, and restored mitochondrial membrane potential in MPP⁺-treated SH-SY5Y cells. These protection effects of herbal extracts are acting through enhancing FBXO7 and decreasing TRAF2 expression, which is probably mediated by GATA2 induction.

CONCLUSION

Collectively, our study provides new targets, FBXO7 and its regulator GATA2, for the development of potential treatments of PD.