One-step simultaneous liquid phase exfoliation-induced chirality in graphene and their chirality-mediated microRNA delivery

Graphene (G) has established itself as an exciting prospect for a broad range of applications owing to its remarkable properties. Recent innovations in chiral nanosystems have led to sensors, drug delivery, catalysis, etc. owing to the stereospecific interactions between various nanosystems and enantiomers. As the molecular structure of G itself is achiral introducing chirality in G by simple attachment of a functional group (a chiral ligand) on the G nanosheet may result in more diverse applications. Herein, we demonstrate direct liquid phase exfoliation and chiral induction in G nanosheets abbreviated as L-graphene and D-graphene in the presence of chiral L-tyrosine and D-tyrosine and by applying high-temperature sonication. The obtained exfoliated nanosheets demonstrated stable chirality confirmed by circular dichroism. Fourier transform infrared (FTIR) spectra, Raman spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and differential scanning calorimetry (DSC) showed functional, structural, morphological, surface, and thermal characteristics of L-graphene and D-graphene. The hemo-compatibility of these chiral graphenes was evaluated for the very first time utilizing human red blood cells. Lastly, for the very first time, an attempt was made to explore enantiomeric binding between chiral L-graphene and D-graphene with microRNA (miR-205) and their possibility towards chirality-mediated gene delivery in prostate cancerous cells

Comparative neurohormonal responses in patients with preserved and impaired left ventricular ejection fraction: Results of the studies of left ventricular dysfunctions (SOLVD) registry

AbstractObjectives. The aim of this study was to determine the differences in neurohumoral responses between patients with pulmonary congestion with and without impaired left ventricular ejection fraction.Background. Previous studies have established the presence of neurohumoral activation in patients with congestive heart failure. It is not known whether the activation of these neurohumoral mechanisms is related to the impairment in systolic contractility.Methods. The 898 patients recruited into the Studies of Left Ventricular Dysfunction (SOLVD) Registry substudy were examined to identify those patients with pulmonary congestion on chest X-ray film who had either unpaired (<- 45%, group I) or preserved (> 45%, group II) left ventricular ejection fraction. Plasma norepinephrine, plasma renin activity, arginine vasopressin and atrial natriuretic peptide levels were measured in these two groups of patients and compared with values in matched control subjects,Results. Distribution of the New York Heart Association symptom classification was the same in the two groups of patients. Compared with control subjects, patients in group II with pulmonary congestion and preserved ejection fraction had no activation of the neurohumoral mechanisms, except for a small but statistically significant increase in arginine vasopressin and plasma renin activity. Compared with patients in group II, those in group I with pulmonary congestion and unpaired ejection fraction had significant increases in plasma norepinephrine (p < 0.002), plasma renin activity (p < 0.02) and atrial natriuretic peptide levels (p < 0.0007). When we controlled for baseline differences between groups I and II, the between-group differences in plasma norepinephrine (p < 0.02) and atrial natriuretic peptide (p < 0.002) remained significant. However, plasma renin activity was not significantly different between groups I and II. When the effects of diuretic agents and angiotensinconverting enzyme inhibitors were adjusted, patients with lower ejection fraction were found to have significantly higher plasma norepinephrine and atrial natriuretic peptide levels.Conclusions. The results point to the importance of the decrease in left ventricular ejection fraction as one of the mechanisms for activation of neurohormones in patients with heart failure

Engineering of quantum dot photon sources via electro-elastic fields

The possibility to generate and manipulate non-classical light using the tools of mature semiconductor technology carries great promise for the implementation of quantum communication science. This is indeed one of the main driving forces behind ongoing research on the study of semiconductor quantum dots. Often referred to as artificial atoms, quantum dots can generate single and entangled photons on demand and, unlike their natural counterpart, can be easily integrated into well-established optoelectronic devices. However, the inherent random nature of the quantum dot growth processes results in a lack of control of their emission properties. This represents a major roadblock towards the exploitation of these quantum emitters in the foreseen applications. This chapter describes a novel class of quantum dot devices that uses the combined action of strain and electric fields to reshape the emission properties of single quantum dots. The resulting electro-elastic fields allow for control of emission and binding energies, charge states, and energy level splittings and are suitable to correct for the quantum dot structural asymmetries that usually prevent these semiconductor nanostructures from emitting polarization-entangled photons. Key experiments in this field are presented and future directions are discussed.Comment: to appear as a book chapter in a compilation "Engineering the Atom-Photon Interaction" published by Springer in 2015, edited by A. Predojevic and M. W. Mitchel

Identifying priorities in methodological research using ICD-9-CM and ICD-10 administrative data: report from an international consortium

BACKGROUND: Health administrative data are frequently used for health services and population health research. Comparative research using these data has been facilitated by the use of a standard system for coding diagnoses, the International Classification of Diseases (ICD). Research using the data must deal with data quality and validity limitations which arise because the data are not created for research purposes. This paper presents a list of high-priority methodological areas for researchers using health administrative data. METHODS: A group of researchers and users of health administrative data from Canada, the United States, Switzerland, Australia, China and the United Kingdom came together in June 2005 in Banff, Canada to discuss and identify high-priority methodological research areas. The generation of ideas for research focussed not only on matters relating to the use of administrative data in health services and population health research, but also on the challenges created in transitioning from ICD-9 to ICD-10. After the brain-storming session, voting took place to rank-order the suggested projects. Participants were asked to rate the importance of each project from 1 (low priority) to 10 (high priority). Average ranks were computed to prioritise the projects. RESULTS: Thirteen potential areas of research were identified, some of which represented preparatory work rather than research per se. The three most highly ranked priorities were the documentation of data fields in each country's hospital administrative data (average score 8.4), the translation of patient safety indicators from ICD-9 to ICD-10 (average score 8.0), and the development and validation of algorithms to verify the logic and internal consistency of coding in hospital abstract data (average score 7.0). CONCLUSION: The group discussions resulted in a list of expert views on critical international priorities for future methodological research relating to health administrative data. The consortium's members welcome contacts from investigators involved in research using health administrative data, especially in cross-jurisdictional collaborative studies or in studies that illustrate the application of ICD-10

Description and evaluation of an EBM curriculum using a block rotation

BACKGROUND: While previous authors have emphasized the importance of integrating and reinforcing evidence-based medicine (EBM) skills in residency, there are few published examples of such curricula. We designed an EBM curriculum to train family practice interns in essential EBM skills for information mastery using clinical questions generated by the family practice inpatient service. We sought to evaluate the impact of this curriculum on interns, residents, and faculty. METHODS: Interns (n = 13) were asked to self-assess their level of confidence in basic EBM skills before and after their 2-week EBM rotation. Residents (n = 21) and faculty (n = 12) were asked to assess how often the answers provided by the EBM intern to the inpatient service changed medical care. In addition, residents were asked to report how often they used their EBM skills and how often EBM concepts and tools were used in teaching by senior residents and faculty. Faculty were asked if the EBM curriculum had increased their use of EBM in practice and in teaching. RESULTS: Interns significantly increased their confidence over the course of the rotation. Residents and faculty felt that the answers provided by the EBM intern provided useful information and led to changes in patient care. Faculty reported incorporating EBM into their teaching (92%) and practice (75%). Residents reported applying the EBM skills they learned to patient care (86%) and that these skills were reinforced in the teaching they received outside of the rotation (81%). All residents and 11 of 12 faculty felt that the EBM curriculum had improved patient care. CONCLUSIONS: To our knowledge, this is the first published EBM curriculum using an individual block rotation format. As such, it may provide an alternative model for teaching and incorporating EBM into a residency program

Process evaluation for complex interventions in primary care: understanding trials using the normalization process model

Background: the Normalization Process Model is a conceptual tool intended to assist in understanding the factors that affect implementation processes in clinical trials and other evaluations of complex interventions. It focuses on the ways that the implementation of complex interventions is shaped by problems of workability and integration.Method: in this paper the model is applied to two different complex trials: (i) the delivery of problem solving therapies for psychosocial distress, and (ii) the delivery of nurse-led clinics for heart failure treatment in primary care.Results: application of the model shows how process evaluations need to focus on more than the immediate contexts in which trial outcomes are generated. Problems relating to intervention workability and integration also need to be understood. The model may be used effectively to explain the implementation process in trials of complex interventions.Conclusion: the model invites evaluators to attend equally to considering how a complex intervention interacts with existing patterns of service organization, professional practice, and professional-patient interaction. The justification for this may be found in the abundance of reports of clinical effectiveness for interventions that have little hope of being implemented in real healthcare setting

Određivanje aflatoksina, okratoksina A, fumonizina i zearalenona u žitaricama i krmivu primjenom kompetetivnoga direktnog imunoenzimatskog testa (CD-ELISA) i tankoslojne kromatografije (TLC)

Aspergillus, Penicillium, and Fusarium species frequently contaminate crops. For this reason mycotoxins such as afl atoxins (AFs), ochratoxin A (OTA), fumonisins (FBs), and zearalenone (ZEA) are found in food and feed in a wide range of concentrations, depending on environmental and storage conditions. Consumption of mycotoxin-contaminated food and feed has been associated with acute and chronic poisoning and carcinoma. The aim of this study was to determine the incidence and co-occurrence of AFs (B1+B2+G1+G2), OTA, FBs (B1+B2+B3), and ZEA in 37 samples of cereals and feed randomly collected in 2007 from households of an endemic nephropathy (EN) area in Croatia. The mycotoxins were determined using the competitive direct ELISA test (CD-ELISA) in combination with thin-layer chromatography (TLC). The most frequent mycotoxin was ZEA (92 %, mean 318.3 μg kg-1), followed by FBs (27 %, 3690 μg kg-1), AFs (24.3 %, 4.6 μg kg-1), and OTA (16.2 %, 9.8 μg kg-1). Levels of AFs, ZEA, and FBs detected by CD-ELISA signifi cantly correlated with the TLC results. However, only one OTA-positive sample was confi rmed by TLC due to its high limit of detection. The levels of these mycotoxins were below the permissible limit for animal feed. Twenty-nine percent of cereals were contaminated with FBs, OTA, or ZEA in mass fractions above the permissible limit for humans. Co-occurrence of two toxins varied between 4.2 % and 54 % and of three between 4.2 % and 7.6 %. Prolonged co-exposure to AFs, OTA, FBs, and ZEA might increase the risk of various chronic diseases.Vrste plijesni iz rodova Aspergillus, Penicillium i Fusarium česti su kontaminanti usjeva te na takvim supstratima tvore mikotoksine. Stoga su žitarice i krmiva često kontaminirana afl atoksinima (AFs), okratoksinom A (OTA), fumonizinima (FBs) i zearalenonom (ZEA) u različitim koncentracijama ovisno o mikroklimatskim uvjetima na polju i u skladištu. Konzumiranje hrane kontaminirane mikotoksinima često je povezano s akutnim ili kroničnim trovanjima, ali i s razvojem karcinoma. Cilj ovog rada bio je odrediti istodobnu pojavnost AFs (B1+B2+G1+G2), OTA, FBs (B1+B2+B3) i ZEA u uzorcima žitarica i krme (N=37) koji su nasumično skupljeni u individualnim domaćinstvima na području endemske nefropatije (EN) u Hrvatskoj (2007). Za određivanje navedenih mikotoksina korišten je kompetitivni direktni ELISA-test (CD-ELISA) u kombinaciji s tankoslojnom kromatografi jom (TLC). Najzastupljeniji mikotoksin bio je ZEA (92 %, srednja koncentracija 318.3 μg kg-1), nakon čega slijede FBs (27 %, 3690 μg kg-1), AFs (24.3 %, 4.6 μg kg-1) te OTA (16.2 %, 9.8 μg kg-1). Koncentracije AFs, FBs i ZEA određene CD-ELISA-testom statistički značajno koreliraju s rezultatima dobivenim s TLC. OTA je potvrđen metodom TLC samo u jednom uzorku zbog visokog limita detekcije. Dokazane koncentracije su ispod razina dopuštenih za krmiva, dok je 29 % uzoraka žitarica sadržavalo FBs, OTA ili ZEA u koncentracijama iznad dopuštenih u hrani za ljude. Kokontaminacija s dvama odnosno trima toksinima varirala je između 4.2 % i 54 % odnosno između 4.2 % i 7.6 %. Dugotrajni unos AFs, OTA, FBs i ZEA putem hrane može povećati rizik od razvoja različitih kroničnih bolesti zbog njihova mogućega sinergističkog djelovanja

Osteogenesis evaluation of duck’s feet derived collagen/hydroxyapatite sponges immersed in dexamethasone

Background: The aim of this study was to investigate the osteogenesis effects of DC and DC/HAp sponge immersed in without and with dexamethasone. Methods: The experimental groups in this study were DC and DC/HAp sponge immersed in without dexamethasone (Dex(â )DC and Dex(â )-DC/HAp group) and with dexamethasone (Dex(+)-DC and Dex(+)-DC/HAp group). We characterized DC and DC/HAp sponge using compressive strength, scanning electron microscopy (SEM). Also, osteogenic differentiation of BMSCs on sponge (Dex(â )DC, Dex(â )-DC/HAp, Dex(+)-DC and Dex(+)-DC/HAp group) was assessed by SEM, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazoliumbromide (MTT) assay, alkaline phosphatase (ALP) activity assay and reverse transcription-PCR (RT-PCR). Results: In this study, we assessed osteogenic differentiation of BMSCs on Duckâ s feet-derived collagen (DC)/ HAp sponge immersed with dexamethasone Dex(+)-DC/HAp. These results showed that Dex(+)-DC/HAp group increased cell proliferation and osteogenic differentiation of BMSCs during 28 days. Conclusion: From these results, Dex(+)-DC/HAp can be envisioned as a potential biomaterial for bone regeneration applications.This work was supported by Technology Commercialization Support Program [grant number 814005-03-3-HD020], Ministry for Food, Agriculture, Forestry and Fisheries (MIFAFF).info:eu-repo/semantics/publishedVersio