Miracle-dz/UniFAR-FTUs huggingface dataset:
Determination of the minimal melatonin exposure required to induce osteoblast differentiation from human mesenchymal stem cells and these effects on downstream signaling pathways

Abstract: The purpose of this study was to determine the critical time periods of melatonin treatment required to induce human mesenchymal stem cells (hAMSCs) into osteoblasts and to determine which osteogenic genes are involved in the process. The study design consisted of adding melatonin for different times (2, 5, 10, 14 or 21 days) toward the end of a 21‐day treatment containing osteogenic (OS+) medium or at the beginning of the 21‐day treatment and then withdrawn. The results show that a 21‐day continuous melatonin treatment was required to induce both alkaline phosphatase (ALP) activity and calcium deposition and these effects were mediated through MT2Rs. Functional analysis revealed that peak ALP levels induced by melatonin were accompanied by attenuation of melatonin‐mediated inhibition of forskolin‐induced cAMP accumulation. Immunoprecipitation and western blot analyses, respectively, showed that MT2R/β‐arrestin scaffolds complexed to Gi, MEK1/2 and ERK1/2 formed in these differentiated hAMSCs (i.e., when ALP levels were highest) where ERK1/2 resided primarily in the cytosol. It is hypothesized that these complexes form to modulate the subcellular localization of ERK1/2 to affect osteogenic gene expression. Using real‐time RT‐PCR, chronic melatonin exposure induced the expression of osteogenic genes RUNX‐2, osteocalcin and BMP‐2, through MT2Rs. No melatonin‐mediated changes in the mRNA expression of ALP, BMP‐6 or in the oxidative enzymes MtTFA, PGC‐1α, Polγ, NRF‐1, PDH, PDK and LDH occurred. These data show that a continuous 21‐day melatonin exposure is required to induce osteoblast differentiation from hAMSCs through the formation of MT2R/Gi/β‐arrestin/MEK/ERK1/2 complexes to induce osteogenesis.
Myeloid STAT3 inhibits T cell-mediated hepatitis by regulating T helper 1 cytokine and interleukin-17 production.

BACKGROUND & AIMS T cell-mediated hepatitis is a leading cause of acute liver failure; there is no effective treatment, and the mechanisms underlying its pathogenesis are obscure. The aim of this study was to investigate the immune cell-signaling pathways involved-specifically the role of signal transducer and activator of transcription 3 (STAT3)-in T cell-mediated hepatitis in mice. METHODS T cell-mediated hepatitis was induced in mice by injection of concanavalin A (Con A). Mice with myeloid cell-specific and T-cell-specific deletion of STAT3 were generated. RESULTS STAT3 was activated in myeloid and T cells following Con A injection. Deletion of STAT3 specifically from myeloid cells exacerbated T-cell hepatitis and induced STAT1-dependent production of a T helper cell (Th)1 cytokine (interferon [IFN]-gamma) and to a lesser extent of Th17 cytokines (interleukin [IL]-17 and IL-22) in a STAT1-independent manner. In contrast, deletion of STAT3 in T cells reduced T cell-mediated hepatitis and IL-17 production. Furthermore, deletion of IFN-gamma completely abolished Con A-induced T-cell hepatitis, whereas deletion of IL-17 slightly but significantly reduced such injury. In vitro experiments indicated that IL-17 promoted liver inflammation but inhibited hepatocyte apoptosis. CONCLUSIONS Myeloid STAT3 activation inhibits T cell-mediated hepatitis via suppression of a Th1 cytokine (IFN-gamma) in a STAT1-dependent manner, whereas STAT3 activation in T cells promotes T-cell hepatitis to a lesser extent, via induction of IL-17. Therefore, activation of STAT3 in myeloid cells could be a novel therapeutic strategy for patients with T-cell hepatitis.
Antimalarial Action of Artesunate Involves DNA Damage Mediated by Reactive Oxygen Species

ABSTRACT Artemisinin-based combination therapy (ACT) is the recommended first-line treatment for Plasmodium falciparum malaria. It has been suggested that the cytotoxic effect of artemisinin is mediated by free radicals followed by the alkylation of P. falciparum proteins. The endoperoxide bridge, the active moiety of artemisinin derivatives, is cleaved in the presence of ferrous iron, generating reactive oxygen species (ROS) and other free radicals. However, the emergence of resistance to artemisinin in P. falciparum underscores the need for new insights into the molecular mechanisms of antimalarial activity of artemisinin. Here we show that artesunate (ART) induces DNA double-strand breaks in P. falciparum in a physiologically relevant dose- and time-dependent manner. DNA damage induced by ART was accompanied by an increase in the intracellular ROS level in the parasites. Mannitol, a ROS scavenger, reversed the cytotoxic effect of ART and reduced DNA damage, and modulation of glutathione (GSH) levels was found to impact ROS and DNA damage induced by ART. Accumulation of ROS, increased DNA damage, and the resulting antiparasite effect suggest a causal relationship between ROS, DNA damage, and parasite death. Finally, we also show that ART-induced ROS production involves a potential role for NADPH oxidase, an enzyme involved in the production of superoxide anions. Our results with P. falciparum provide novel insights into previously unknown molecular mechanisms underlying the antimalarial activity of artemisinin derivatives and may help in the design of next-generation antimalarial drugs against the most virulent Plasmodium species.
Validation of the CSA accelerometer for assessing children's physical activity.

The Computer Science Application (CSA) accelerometer is designed to detect the acceleration and deceleration of human movement. The purpose of this study was to evaluate its validity and utility for measuring children's activity in field settings. The criterion measure was heart rate telemetry. This study also examined the between-day stability of children's physical activity. Thirty-one children (7-15 yr) wore a CSA accelerometer and a heart rate telemetry monitor for 12 h.d-1 for 3 consecutive days. The validity correlation coefficients between accelerometry and heart rate telemetry for each monitored day ranged from r = 0.50-0.74. All children reported the accelerometer to be comfortable to wear. The moderate to high validity correlations and the subjects' favorable response to wearing the accelerometer support its validity and utility as an objective method for monitoring activity in children in field settings. However, the between-day stability of individual physical activity measures was low to moderate (r = -0.23 to 0.53), indicating that when using accelerometry or heart rate telemetry more than 3 d of monitoring is needed to assess usual activity.
How Did the Economic Crisis Influence New Firm Creation?

Summary There is a broad consensus that the likelihood of becoming an entrepreneur is not only influenced by individual characteristics but also by spatial context conditions. However, context factors are not per se stable; they tend to vary over time which is particularly relevant during economic cycles. In Germany, for instance, the rapid economic downturn of 2008/2009 was preceded by a period of growth and followed by an economic upswing in many regions. However, the impact of this crisis on entrepreneurship has not been empirically studied comprehensively. Using data from the Global Entrepreneurship Monitor (GEM), we analyse entrepreneurial activities in the 39 German NUTS2 regions covering a 13-year period before, during and after the Great Recession of 2008/2009. Applying multilevel regression techniques, we hypothesize that both space and time matter for individual entrepreneurial behaviour. Our results show, first, that space and time can be regarded as two interrelated dimensions that jointly impact entrepreneurial activities. Second, similar individual attributes are associated with diverging likelihoods of becoming an entrepreneur in case individuals are nested in different regions or different time periods and are thus exposed to dissimilar context conditions. Third, the type and number of individual, context and interaction effects are motive-related, i.e. they depend on whether the entrepreneurial action is either opportunity-driven or necessity-driven.
Optimization of Spring-Loaded Crutches via Boundary Value Problem

The objective of the work is to optimize the design of spring-loaded crutches by choosing appropriate spring stiffness based on their dynamic characteristics. It was shown in the literature that ambulation with spring-loaded crutches reduces the initial impulse yielded by ambulation with standard crutches and provides a propulsion mechanism. This research not only provides a genre of the spring-loaded crutches via compliance, but also proposes an approach to optimize the stiffness of the helical spring through studying the dynamics of crutch stance. The method is developed using a boundary value problem and its solution method and is studied numerically. Experiments were carried out on four subjects in a biomechanics laboratory. It suggests that the optimized spring-loaded crutches guarantee the propulsion mechanism at the right time and right position during dynamical ambulation.
QSAR Modeling of in Vitro Inhibition of Cytochrome P450 3A4

We report the QSAR modeling of cytochrome P450 3A4 (CYP3A4) enzyme inhibition using four large data sets of in vitro data. These data sets consist of marketed drugs and drug-like compounds all tested in four assays measuring the inhibition of the metabolism of four different substrates by the CYP3A4 enzyme. The four probe substrates are benzyloxycoumarin, testosterone, benzyloxyresorufin, and midazolam. We first show that using state-of-the-art QSAR modeling approaches applied to only one of these four data sets does not lead to predictive models that would be useful for in silico filtering of chemical libraries. We then present the development and the testing of a multiple pharmacophore hypothesis (MPH) that is formulated as a conceptual extension of the traditional QSAR approach to modeling the promiscuous binding of a large variety of drugs to CYP3A4. In the simplest form, the MPH approach takes advantage of the multiple substrate data sets and identifies the binding of test compounds as either proximal or distal relative to that of a given substrate. Application of the approach to the in silico filtering of test compounds for potential inhibitors of CYP3A4 is also presented. In addition to an improvement in the QSAR modeling for the inhibition of CYP3A4, the results from this modeling approach provide structural insights into the drug-enzyme interactions. The existence of multiple inhibition data sets in the BioPrint database motivates the original development of the concept of a multiple pharmacophore hypothesis and provides a unique opportunity for formulating alternative strategies of QSAR modeling of the inhibition of the in vitro metabolism of CYP3A4.
Differential Replication of Two Chloroplast Genome Forms in Heteroplasmic Chlamydomonas reinhardtii Gametes Contributes to Alternative Inheritance Patterns

Two mechanisms for chloroplast DNA replication have been revealed through the study of an unusual heteroplasmic strain of the green alga Chlamydomonas reinhardtii. Heteroplasmy is a state in which more than one genome type occurs in a mitochondrion or chloroplast. The Chlamydomonas strain spa19 bears two distinct chloroplast genomes, termed PS+ and PS−. PS+ genomes predominate and are stably maintained in vegetative cells, despite their lack of known replication origins. In sexual crosses with spa19 as the mating type plus parent, however, PS+ genomes are transmitted in only ∼25% of tetrads, whereas the PS− genomes are faithfully inherited in all progeny. In this research, we have explored the mechanism underlying this biased uniparental inheritance. We show that the relative reduction and dilution of PS+ vs. PS− genomes takes place during gametogenesis. Bromodeoxyuridine labeling, followed by immunoprecipitation and PCR, was used to compare replication activities of PS+ and PS− genomes. We found that the replication of PS+ genomes is specifically suppressed during gametogenesis and germination of zygospores, a phenomenon that also was observed when spa19 cells were treated with rifampicin, an inhibitor of the chloroplast RNA polymerase. Furthermore, when bromodeoxyuridine incorporation was compared at 11 sites within the chloroplast genome between vegetative cells, gametes, and rifampicin-treated cells by quantitative PCR, we found that incorporation was often reduced at the same sites in gametes that were also sensitive to rifampicin treatment. We conclude that a transcription-mediated form of DNA replication priming, which may be downregulated during gametogenesis, is indispensable for robust maintenance of PS+ genomes. These results highlight the potential for chloroplast genome copy number regulation through alternative replication strategies.
Cognitive dysfunction in patients with type 2 diabetes

People with diabetes mellitus are at increased risk of cognitive dysfunction and dementia. This review explores the nature and severity of cognitive changes in patients with type 2 diabetes. Possible risk factors such as hypo‐ and hyperglycemia, vascular risk factors, micro‐ and macrovascular complications, depression and genetic factors will be examined, as well as findings from brain imaging and autopsy studies. We will show that type 2 diabetes is associated with modest cognitive decrements in non‐demented patients that evolve only slowly over time, but also with an increased risk of more severe cognitive deficits and dementia. There is a dissociation between these two ‘types’ of cognitive dysfunction with regard to affected age groups and course of development. Therefore, we hypothesize that the mild and severe cognitive deficits observed in patients with type 2 diabetes reflect separate processes, possibly with different risk factors and aetiologies. Copyright © 2010 John Wiley & Sons, Ltd.
Recombinant adenovirus-mediated gene delivery into the rat retinal pigment epithelium in vivo.

PURPOSE The present paper describes changes following the subretinal injection of a recombinant replication-deficient adenovirus carrying the beta-galactosidase reporter gene construct into the rat retina. METHODS Ad.RSV. betagal-mediated transduction of rat retinal pigment epithelium (RPE) cells in vitro and in vivo was examined following X-gal staining. RESULTS There was a low level of beta-galactosidase expression in the RPE cells at 4 days postinjection. At 7 days postinjection, a strong transgene expression was present in RPE cells and the expression was maintained at 14 days postinjection. Except for the accumulation of cells at the site of the injection, the morphology of the rest of the retina remained normal. CONCLUSION These results demonstrate that the RPE layer can be successfully targeted for gene delivery in the rat.
The genes for butanol and acetone formation in Clostridium acetobutylicum ATCC 824 reside on a large plasmid whose loss leads to degeneration of the strain

Degeneration is the process whereby Clostridium acetobutylicum ATCC 824 loses the capacity to produce acetone and butanol after repeated vegetative transfers or in continuous culture. Two degenerate mutants (M5 and DG1) of C. acetobutylicum ATCC 824 do not contain the four genes (ctfA, ctfB, adc, and aad) for acetone and butanol formation. Strain ATCC 824 contains a 210-kb plasmid (pSOL1) which is absent in M5 and DG1. pSOL1 carries the four acetone and butanol formation genes. A restriction map of pSOL1 was constructed by using ApaI, SmaI, SstII, and NarI digestions. M5 and DG1 could be complemented for acetone and butanol formation by expressing the corresponding genes (ctfA, ctfB, and adc for acetone; aad for butanol) on the plasmid. Degeneration of this strain thus appears to be the result of pSOL1 loss.
Therapeutic Potential of the Poly(ADP-ribose) Polymerase Inhibitor Rucaparib for the Treatment of Sporadic Human Ovarian Cancer

Here, we investigate the potential role of the PARP inhibitor rucaparib (CO-338, formerly known as AG014699 and PF-01367338) for the treatment of sporadic ovarian cancer. We studied the growth inhibitory effects of rucaparib in a panel of 39 ovarian cancer cell lines that were each characterized for mutation and methylation status of BRCA1/2, baseline gene expression signatures, copy number variations of selected genes, PTEN status, and sensitivity to platinum-based chemotherapy. To study interactions with chemotherapy, we used multiple drug effect analyses and assessed apoptosis, DNA fragmentation, and γH2AX formation. Concentration-dependent antiproliferative effects of rucaparib were seen in 26 of 39 (67%) cell lines and were not restricted to cell lines with BRCA1/2 mutations. Low expression of other genes involved in homologous repair (e.g., BCCIP, BRCC3, ATM, RAD51L1), amplification of AURKA or EMSY, and response to platinum-based chemotherapy was associated with sensitivity to rucaparib. Drug interactions with rucaparib were synergistic for topotecan, synergistic, or additive for carboplatin, doxorubicin or paclitaxel, and additive for gemcitabine. Synergy was most pronounced when rucaparib was combined with topotecan, which resulted in enhanced apoptosis, DNA fragmentation, and γH2AX formation. Importantly, rucaparib potentiated chemotherapy independent of its activity as a single agent. PARP inhibition may be a useful therapeutic strategy for a wider range of ovarian cancers bearing deficiencies in the homologous recombination pathway other than just BRCA1/2 mutations. These results support further clinical evaluation of rucaparib either as a single agent or as an adjunct to chemotherapy for the treatment of sporadic ovarian cancer. Mol Cancer Ther; 12(6); 1002–15. ©2013 AACR.
'A picture is worth a thousand words': image highlights from Cardiovascular Research.

Communicating the main message or complex concepts/relationships in a publication with limited text is a challenge. As has been said before, this is when ‘A picture is worth a thousand words’ (‘Speakers Give Sound Advice’, Syracuse Post Standard, 28 March 1911, p. 18). An important part of the editorial process is to improve the readability, understanding, and attractiveness of publications for the end user/reader. As such, Cardiovascular Research in a joint effort of the editorial office, Oxford University Press and the European Society of Cardiology, decided to improve the use of images in the journal by both removing colour figure charges and providing free design support for priority publications by a graphics team of scientifically trained illustrators. The aim is (i) to enhance the quality of the message of the study, (ii) make the content more accessible to the broader readership of the journal, and (iii) to supply images for lectures and teaching to the whole community. For this latter aim, all these figures have now been made available to the Cardiovascular Research community in the Cardiovascular Research image repository online, which can be accessed at http://aca demic.oup. com/cardiovascres/pages/image_gallery/main_page. While an image gallery had been available before, the present introduction is of images that were for the largest part designed by the graphics team in an interactive process with the authors. Over the past 3 years since the introduction, the team has strived to optimize code and design for consistency in visualizing structures and pathways, e.g. by standardizing how commonly used items such as muscle cells are depicted in all images.
Preoperative "chemoradiation" for stages II and III rectal carcinoma.

OBJECTIVE To determine whether preoperative administration of combination chemotherapy and external beam irradiation ("chemoradiation") for patients with stage II or stage III rectal carcinoma had an impact on perioperative morbidity on oncologic outcome, as compared with patients not receiving preoperative chemoradiation. DESIGN A group of patients with stage II or stage III rectal carcinoma receiving preoperative chemoradiation were followed up prospectively and compared in a nonrandomized fashion with an inception cohort group of similar patients. SETTING Northwestern Memorial Hospital, Chicago, Ill, a tertiary care academic medical center. PATIENTS Thirty patients with rectal carcinoma undergoing preoperative chemoradiation were compared with 56 patients not undergoing preoperative chemoradiation, and also with a subset group of 24 patients who received standard postoperative adjuvant chemoradiation. INTERVENTION External beam radiation, 45 to 50 Gy, was delivered concurrently with fluorouracil and mitomycin 4 to 8 weeks prior to surgical resection. MAIN OUTCOME MEASURES Patients were followed up at regular intervals for either tumor recurrence or death. In addition, the group receiving preoperative chemoradiation was evaluated for major preoperative morbidity. RESULTS All patients agreeing to preoperative chemoradiation completed therapy. Perioperative major morbidity in this group (13%) was comparable to previously published results. Of the 56 patients with stage II or stage III rectal carcinoma not receiving preoperative chemoradiation, only 24 (43%) completed standard postoperative adjuvant chemoradiation. Patients receiving preoperative chemoradiation (n = 30), patients not receiving preoperative chemoradiation (n = 56), and the subset of the group not receiving preoperative chemoradiation who completed standard postoperative chemoradiation (n = 24) were followed up for a mean of 39 months, 31 months, and 32 months, respectively. Five-year actuarial local control rates were 96%, 83%, and 88%, respectively. Disease-free-survival rates were 80%, 57%, and 47%, respectively. Overall survival rates were 85%, 48%, and 78%, respectively. CONCLUSIONS Preoperative chemoradiation in the treatment of stage II or stage III rectal carcinoma is well tolerated and not associated with an increase in subsequent perioperative major morbidity. In addition, local control, disease-free survival, and overall survival compare favorably with a nonrandomized inception cohort group of patients receiving standard postoperative adjuvant chemoradiation.
A mutation in the Z‐line Cypher/ZASP protein is associated with arrhythmogenic right ventricular cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an important cause of malignant arrhythmia and sudden death particularly in young people. Although it is considered a desmosomal disease, mutations in non‐desmosomal genes have also been identified. We report on a family where a mutation in LDB3 is associated with this condition. The index case and first and second degree relatives underwent a complete clinical evaluation: physical examination, electrocardiography (ECG), signal‐averaged ECG, 2D echocardiogram, cardiac magnetic resonance and 24‐h monitoring. After ruling out mutations in the five desmosomal genes, genetic testing by means of Next Generation Sequencing was carried out on the proband. A heterozygous missense mutation in LDB3 c.1051A>G was identified. This result was confirmed by subsequent Sanger DNA sequencing. Another six carriers were identified amongst her relatives. Three subjects fulfilled the criteria for a definitive diagnosis of ARVC and one reached a borderline diagnosis. In conclusion, this is the first family with ARVC where a mutation in LDB3 is associated with ARVC. Next generation sequencing arises as a particular useful tool to point to new causative genes in ARVC.