TLE4 regulates muscle stem cell quiescence and skeletal muscle differentiation.

Muscle stem (satellite) cells express Pax7, a key transcription factor essential for satellite cell maintenance and adult muscle regeneration. We identify the corepressor transducin-like enhancer of split-4 (TLE4) as a Pax7 interaction partner expressed in quiescent satellite cells under homeostasis. A subset of satellite cells transiently downregulate TLE4 during early time points following muscle injury. We identify these to be activated satellite cells, and that TLE4 downregulation is required for Myf5 activation and myogenic commitment. Our results indicate that TLE4 represses Pax7-mediated Myf5 transcriptional activation by occupying the -111 kb Myf5 enhancer to maintain quiescence. Loss of TLE4 function causes Myf5 upregulation, an increase in satellite cell numbers and altered differentiation dynamics during regeneration. Thus, we have uncovered a novel mechanism to maintain satellite cell quiescence and regulate muscle differentiation mediated by the corepressor TLE4.

UV-A-Induced Photoisomerization and Photodimerization of Curcumin: An Ion Mobility Mass Spectrometry Study.

Curcumin, the bioactive compound present in spice plant turmeric, has been shown to exhibit selective phototoxic activities toward mammalian cancer cells, and it is being used extensively as a photosensitizer (PS) in photodynamic therapies (PDT). However, so far, the fate of curcumin toward photochemical transformations is not well understood. Here we report our findings of a number of novel photochemical reaction channels of curcumin in water-methanol mixture, like photoisomerization, photodimerization, and photooxidation (H2-loss). The reaction was performed by irradiating the curcumin solution with ultraviolet (UV) light of wavelength 350 nm, which is abundant in the earth's troposphere. Product identification and structure elucidation are done by employing an integrated method of drift tube ion mobility mass spectrometry (DTIMS) in combination with high-performance liquid chromatography (HPLC) and collision-induced dissociation (CID) of the mass-selected molecular ions. Two photoisomers of curcumin produced as a result of trans-cis configurational changes about C═C double bonds in the excited state have been identified, and it has been shown that they could serve as the precursors for formation of isomeric dimers via [2 + 2] cycloaddition and H2-loss products. Comparisons of the experimentally measured collision cross-section (CCS) values of the reactant and product ions obtained by the DTIMS method with those predicted by the electronic structure theory are found to be very effective for the discrimination of the produced photoisomers. The observed photochemical reaction channels are potentially significant toward uses of curcumin as a photosensitizer in photodynamic therapy.

The people behind the papers.

Myosin is a major component of the sarcomeres of muscle, but its roles during muscle development are still relatively poorly understood. A new paper in Development investigates the function of a developmentally expressed myosin heavy chain isoform during mice myogenesis. We caught up with the paper's four co-first authors, Megha Agarwal, Akashi Sharma, Pankaj Kumar and Amit Kumar, and their supervisor Sam Mathew (Associate Professor in the Regional Centre for Biotechnology in Faridabad, India) to find out more about the project.

Myosin heavy chain-embryonic regulates skeletal muscle differentiation during mammalian development.

Myosin heavy chain-embryonic (MyHC-emb) is a skeletal muscle-specific contractile protein expressed during muscle development. Mutations in MYH3, the gene encoding MyHC-emb, lead to Freeman-Sheldon and Sheldon-Hall congenital contracture syndromes. Here, we characterize the role of MyHC-emb during mammalian development using targeted mouse alleles. Germline loss of MyHC-emb leads to neonatal and postnatal alterations in muscle fiber size, fiber number, fiber type and misregulation of genes involved in muscle differentiation. Deletion of Myh3 during embryonic myogenesis leads to the depletion of the myogenic progenitor cell pool and an increase in the myoblast pool, whereas fetal myogenesis-specific deletion of Myh3 causes the depletion of both myogenic progenitor and myoblast pools. We reveal that the non-cell-autonomous effect of MyHC-emb on myogenic progenitors and myoblasts is mediated by the fibroblast growth factor (FGF) signaling pathway, and exogenous FGF rescues the myogenic differentiation defects upon loss of MyHC-emb function in vitro Adult Myh3 null mice exhibit scoliosis, a characteristic phenotype exhibited by individuals with Freeman-Sheldon and Sheldon-Hall congenital contracture syndrome. Thus, we have identified MyHC-emb as a crucial myogenic regulator during development, performing dual cell-autonomous and non-cell-autonomous functions.This article has an associated 'The people behind the papers' interview.

Repurposing of artesunate, an antimalarial drug, as a potential inhibitor of hepatitis E virus.

Hepatitis E virus (HEV) is endemic in several developing countries of Africa and Asia. It mainly causes self-limiting waterborne infections, in either sporadic or outbreak form. Recently, HEV was shown to cause chronic infections in immunosuppressed individuals. Ribavirin and interferon, the current off-label treatment options for hepatitis E, have several side effects. Hence, there is a need for new drugs. We evaluated the antimalarial drug artesunate (ART) against genotype 1 HEV (HEV-1) and HEV-3 using a virus-replicon-based cell culture system. ART exhibited 59% and 43% inhibition of HEV-1 and HEV-3, respectively, at the highest nontoxic concentration. Computational molecular docking analysis showed that ART can bind to the helicase active site (affinity score, -7.4 kcal/mol), indicating its potential to affect ATP hydrolysis activity. An in vitro ATPase activity assay of the helicase indeed showed 24% and 55% inhibition at 19.5 µM (EC50) and 78 µM concentrations of ART, respectively. Since ATP is a substrate of RNA-dependent RNA polymerase (RdRp) as well, we evaluated the effect of ART on the enzymatic activity of the viral polymerase. Interestingly, ART showed 26% and 40% inhibition of the RdRp polymerase activity at 19.5 µM and 78 µM concentrations of ART, respectively. It could be concluded from these findings that ART inhibited replication of both HEV-1 and HEV-3 by directly targeting the activities of the viral enzymes helicase and RdRp. Considering that ART is known to be safe in pregnant women, we think this antimalarial drug deserves further evaluation in animal models.

Spectrum of Non diabetic kidney disease in patients with type 2 diabetes and its clinicopathological correlation.

Diabetes mellitus (DM) is the leading cause of chronic kidney disease worldwide chiefly attributable to diabetic nephropathy (DN). In these patients, non diabetic kidney disease (NDKD) can also occur either alone or superimposed on diabetic nephropathy. This study aimed to identify the prevalence and the etiology of NDKD in our center and also the clinical and laboratory parameters to help distinguish these two entities. MATERIAL: This was a cross sectional observational study. A total of 47 patients were enrolled in the study during the study period. In all the patients, kidney biopsy was done because of atypical presentations and was examined by light and immunofluorescence microscopy. The clinical & laboratory parameters and the biopsy findings were recorded in a standard proforma. OBSERVATION: A total of 47 patients (male/female: 34/13 and mean age 52.11±9.36) were included in the study. The chief co morbidity was hypertension which was present in 61.7% of patients. The most common indication of biopsy was nephrotic presentation (38.3%) followed by nephritic illness (25.5%). The prevalence of NDKD in our study cohort was 85.1% of which isolated NDKD was 57.4% and NDKD + DN was 27.7%. The most common histological lesion were membranous glomerulopathy and focal segmental glomerulosclerosis (FSGS) each with a frequency of 15% followed by chronic tubulointerstitial nephritis (CTIN), IgA nephropathy and others. There was significant difference in the median duration of diabetes in these groups and it was around 5 years less in the NDKD group. There was no difference among three groups in term of eGFR, HbA1C and proteinuria. CONCLUSION: Our study demonstrated a high prevalence of NDKD in the patients with type 2 diabetes. The duration of diabetes was the strongest predictor of NDKD. Kidney biopsy should be undertaken liberally whenever there is strong clinical suspicion especially in the presence of atypical features. The exact histological diagnosis can clarify the further treatment planning as well as the prognosis.

Cardiovascular Effects of Androgen Deprivation Therapy in Prostate Cancer.

PURPOSE OF THE REVIEW: This review paper is a comprehensive look at the cardiovascular disease (CVD) risk that is associated with the use of androgen deprivation therapy in prostate cancer. It summarizes when certain cancer therapies are indicated and should guide physicians in identifying patients at increased risk for CVD during prostate cancer therapy. RECENT FINDINGS: GnRH agonist use and maximal androgen blockade (MAB) are associated with increased CVD. This association is not observed in patients on GnRH antagonists. One example is the novel agent abiraterone, which is associated with hypertension whose mechanisms are likely driven by mineralocorticoid excess. Incidence of cardiovascular disease events is greatest when using MAB, especially in patients with pre-existing CVD. There is significant confounding that exists given patients with more aggressive cancers tend to be older and have more co-existing CVD. Given the lower CVD event rates with GnRH antagonists, future studies and strategies should focus on high-risk cancer patients with co-existing CVD receiving antagonists over agonists.

Genetic characterization of chikungunya viruses isolated during the 2015-2017 outbreaks in different states of India, based on their E1 and E2 genes.

During 2015-2017, chikungunya virus (CHIKV) showed a resurgence in several parts of India with Karnataka, Maharashtra and New Delhi accounting for a majority of the cases. E2-E1 gene based characterization revealed Indian subcontinent sublineage strains possessing Aedes aegypti mosquito-adaptive mutations E1: K211E and E2:V264A, with the 211 site positively selected. Novel mutational sites E1: K16E/Q, E1: K132Q/T, E1: S355T, E2: C19R and E2:S185Y could be associated with epitopes or virulence determining domains. The study examines the role of host, vector and viral factors and fills gaps in our molecular epidemiology data for these regions which are known to possess a dynamic population.

Tyrosine Kinase Inhibitor-Induced Hypertension.

PURPOSE OF REVIEW: The purpose of this paper is to identify commonly used tyrosine kinase inhibitors (TKIs) that are associated with hypertension, primarily, vascular endothelial growth factor (VEGF) signaling pathway (VSP) inhibitors. We review the incidence, mechanism, and strategies for management of TKI-induced HTN. We hope to provide clinicians with guidance on how to manage similar clinical scenarios. RECENT FINDINGS: Many of the newer VSP inhibitors are reviewed here, including cediranib, axitinib, pazopanib, and ponatinib. Trials utilizing prophylactic treatment with angiotensin system inhibitors (ASIs) are discussed as well as recent data showing an improvement in overall survival and progression-free survival in patients on ASIs and TKI-induced hypertension. The incidence of TKI-induced HTN among the VEGF inhibitors ranges from 5 to 80% and is dose dependent. Newer generation small-molecule TKIs has a lower incidence. The mechanism of action involves VSP inhibition, leading to decreased nitric oxide and increased endothelin production, which causes vasoconstriction, capillary rarefaction, and hypertension. ASIs and calcium channel blockers are first-line therapy for treatment and are associated with improved overall survival. Nitrates and beta-blockers are associated with in vitro cancer regression; however, there is a paucity of trials regarding their use as an anti-hypertensive agent in the TKI-induced HTN patient population.

Role of Stress Cardiac Magnetic Resonance Imaging in Women with Suspected Ischemia but No Obstructive Coronary Artery Disease.

OBJECTIVE: Signs and symptoms of ischemia but no obstructive coronary artery disease (CAD) is often a diagnostic dilemma in women. The use of stress cardiac magnetic resonance imaging (CMRI) for advanced diagnostic assessment in these patients is a non-ionizing radiation option, but the diagnostic utility in this population is unknown. We examined the diagnostic role of stress CMRI in our patient population of these women. METHODS: We analyzed 113 consecutive female patients from 2/2006-11/2007 who had prior cardiac evaluations for signs and symptoms of ischemia but no obstructive CAD who underwent stress CMRI, which included anatomic, functional, adenosine stress perfusion and delayed enhancement imaging. RESULTS: The population demographics of 113 women included a mean age of 55±12.2 years with an average body mass index (BMI) of 25 ± 4.5. Overall, 43% had hypertension, 4% had diabetes and 3% were smokers. Overall, 80/113 (70%) demonstrated abnormal stress CMRI results. The majority of patients demonstrated findings consistent with subendocardial perfusion abnormalities suggestive of coronary microvascular dysfunction (CMD). Of note, 3 patients (4%) were diagnosed with congenital coronary anomalies or cardiomyopathy not detected in prior cardiac evaluations. CONCLUSION: Among women with signs and symptoms of ischemia but no obstructive CAD, stress CMRI is frequently abnormal and is valuable in diagnosis of CMD. Stress CMRI appears useful for advanced diagnostic assessment in these diagnostically challenged patients.

The Groucho/Transducin-like enhancer of split protein family in animal development.

Corepressors are proteins that cannot bind DNA directly but repress transcription by interacting with partner proteins. The Groucho/Transducin-Like Enhancer of Split (TLE) are a conserved family of corepressor proteins present in animals ranging from invertebrates such as Drosophila to vertebrates such as mice and humans. Groucho/TLE proteins perform important functions throughout the life span of animals, interacting with several pathways and regulating fundamental processes such as metabolism. However, these proteins have especially crucial functions in animal development, where they are required in multiple tissues in a temporally regulated manner. In this review, we summarize the functions of the Groucho/TLE proteins during animal development, emphasizing on specific tissues where they play essential roles.

Adult-Onset Blue Rubber Bleb Nevus Syndrome.

A 64-year-old, nondiabetic, nonhypertensive Indian woman was admitted to our hospital for evaluation of lethargy that had been present for the past 10 months. In addition, she had developed multiple, gradually progressive, bluish nodules scattered over the skin and mucous membranes for the preceding 15 years. There was no history of recent weight loss, vomiting of blood, passing of bloody stool, or any other external bleeding. There was no significant family history and medical and surgical history was noncontributory. She had received iron preparations repeatedly in the past.

Aquagenic palmar wrinkling in two Indian patients with special reference to its dermoscopic pattern.

Aquagenic palmar wrinkling (APW), synonymously known as aquagenic syringeal acrokeratoderma, transient aquagenic palmar hyperwrinkling, aquagenic palmoplantar keratoderma, or transient reactive papulotranslucent acrokeratoderma, is a distinctive dermatosis characterized by whitish papules, excessive wrinkling, and possible desquamation of the palms and/or soles after immersion into water for a short time. We describe herein two cases of aquagenic palmar wrinkling in Indian patients with special reference to its dermoscopic pattern. Since its initial description, only a few cases of APW have been described in literature. To the best of our knowledge, APW is a hitherto unreported condition in Indian population.

A curious case of blue-green discoloration in a middle-aged indian man: Chromhidrosis.

INTRODUCTION: Chromhidrosis is a rare sweat gland disorder characterized by the excretion of colored sweat. It can be classified as apocrine, true eccrine, and pseudochromhidrosis. Amongst the different types of chromhidrosis, green chromhidrosis is extremely rare. We describe herein a case of blue green chromhidrosis induced by ingestion of homeopathic medicine. CASE REPORT: A middle aged man presented to us with blue green discoloration of hands and feet. There was a preceding history of ingestion of homeopathic medication. Histopathology from the involved skin showed greenish particles within eccrine glands. Initial blood copper level was high which returned to normal level after discontinuation of the homeopathic medicine. Spectrophotometry revealed high copper content of the green sweat. CONCLUSION: Our case emphasizes the importance of considering any type of ingested medicine, including homeopathic medicine, as a probable cause of chromhidrosis.

Systemic lupus erythematosus cardiomyopathy­a case series demonstrating a reversible form of left ventricular dysfunction.

OBJECTIVE: Myocarditis is reported to be a common postmortem finding of systemic lupus erythematosus (SLE). However, most case reports on SLE cardiomyopathy (CM) have not found evidence of myocarditis upon biopsy. Our aim was to characterize the nature, course, and reversibility of left ventricular (LV) dysfunction in patients with SLE. METHODS: The records of 526 SLE patients were reviewed. Patients were included if: (1) at least 4 of 11 American College of Rheumatology criteria for SLE were met, (2) testing for erythrocyte sedimentation rate and hs-CRP were performed during hospitalization, and (3) echocardiogram demonstrated left ventricular ejection function (LVEF) <50%. RESULTS: We identified 14 patients meeting study criteria. Mean LVEF was 33.1 ± 9% upon presentation. The main echocardiographic pattern observed was generalized hypokinesis. Twelve patients demonstrated reversal of cardiomyopathy within 1 week, showing a mean improvement in LVEF of 21.0 ± 7%. Of these, 2 patients underwent coronary angiography demonstrating no evidence of obstructive coronary disease, and 1 underwent cardiac biopsy with no evidence of myocarditis. Four patients (29%) demonstrated improvement within 3 days. Two of the 14 patients died due to their underlying medical illness and did not have a repeat echocardiogram. CONCLUSION: The pattern of wall-motion abnormalities and reversibility demonstrated in the majority of these patients with SLE suggests an etiology more consistent with stress cardiomyopathy rather than myocarditis.

Classification of cyclic alternating patterns of sleep using EEG signals.

Cyclic alternating patterns (CAP) occur in electroencephalogram (EEG) signals during non-rapid eye movement sleep. The analysis of CAP can offer insights into various sleep disorders. The first step is the identification of phases A and B for the CAP cycles. In this work, we develop an easy-to-implement accurate system to differentiate between CAP A and CAP B. Small segments of the EEG signal are processed using Gaussian filters to obtain sub-band components. Features are extracted using some statistical characteristics of these signal components. Minimum redundancy maximum relevance test is employed to identify the more significant features. Three different machine learning classifiers are considered and their performance is compared. The results are analyzed for both the balanced and unbalanced datasets. The k-nearest neighbour (kNN) classifier achieves 79.14 % accuracy and F-1 score of 79.24 % for the balanced dataset. The proposed method outperforms the existing methods for CAP classification. It is easy-to-implement and can be considered as a candidate for real-time deployment.

Can heart failure phenotypes be predicted by cardiac remodelling peripartum or postpartum?

Hypertension during pregnancy affects up to 10% of pregnancies and is associated with significant cardiovascular morbidity and mortality. In the short-term it can result in pre-eclampsia, haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome, or even hypertension associated acute heart failure, all of which may necessitate pre-term delivery to prevent maternal or neonatal death. In the long term, a history of gestational hypertension and pre-eclampsia significantly increases the risk of future cardiovascular disease including chronic hypertension, coronary artery disease, heart failure and stroke. This review explores our current level of knowledge of the phenotypes of heart failure, paying particular attention to those specific to women, and the role of pregnancy and non-pregnancy related risk factors in the development of this condition. We discuss why women with hypertensive pregnancy may be disproportionately affected by heart failure with preserved ejection fraction (HFpEF) and whether a unique phenotype of heart failure unique to hypertensive pregnancy exists. Finally, we explore how future cardiovascular risk may be predicted based on cardiac remodelling during or after pregnancy and suggest potential areas of further research in the field.

The Wnt-pathway corepressor TLE3 interacts with the histone methyltransferase KMT1A to inhibit differentiation in Rhabdomyosarcoma.

Rhabdomyosarcoma tumor cells resemble differentiating skeletal muscle cells, which unlike normal muscle cells, fail to undergo terminal differentiation, underlying their proliferative and metastatic properties. We identify the corepressor TLE3 as a key regulator of rhabdomyosarcoma tumorigenesis by inhibiting the Wnt-pathway. Loss of TLE3 function leads to Wnt-pathway activation, reduced proliferation, decreased migration, and enhanced differentiation in rhabdomyosarcoma cells. Muscle-specific TLE3-knockout results in enhanced expression of terminal myogenic differentiation markers during normal mouse development. TLE3-knockout rhabdomyosarcoma cell xenografts result in significantly smaller tumors characterized by reduced proliferation, increased apoptosis and enhanced differentiation. We demonstrate that TLE3 interacts with and recruits the histone methyltransferase KMT1A, leading to repression of target gene activation and inhibition of differentiation in rhabdomyosarcoma. A combination drug therapy regime to promote Wnt-pathway activation by the small molecule BIO and inhibit KMT1A by the drug chaetocin led to significantly reduced tumor volume, decreased proliferation, increased expression of differentiation markers and increased survival in rhabdomyosarcoma tumor-bearing mice. Thus, TLE3, the Wnt-pathway and KMT1A are excellent drug targets which can be exploited for treating rhabdomyosarcoma tumors.