An investigation on the structure and group vibrations of balenine molecule by matrix isolation IR spectroscopy, DFT and MP2 based calculations

Stable conformers of neutral balenine were scanned through molecular dynamics simulations and energy minimizations using Allinger's MM2 force field. For each of the found minimum-energy conformers, geometry optimization and thermochemistry calculations were performed by using B3LYP, MP2, G3MP2B3 methods, 6-31G(d), 6-311++G(d,p) and aug-cc-pvTZ basis sets. The calculation results have indicated that balenine has about twenty stable conformers whose relative energies are in the range of 0-9.5 kcal/mol. Three of these are thought to provide the major contribution to matrix isolation IR spectra of the molecule. Our solvent calculations using the polarized continuum model revealed the stable zwitterion structures which are predicted to dominate IR spectra of balenine in water and heavy water (D₂O) solvents. Pulay's SQM-FF method was used in scaling of the harmonic force constants and vibrational spectral data calculated for the neutral and zwitterion structures. These refined calculation data together with those obtained from anharmonic frequency calculations enabled us to correctly interpret the matrix isolation IR spectrum of balenine and the tautomerism-based changes observed in its KBr IR and solution (D₂O) IR spectra. The results revealed the crucial role of conformation and zwitterionic tautomerism on the structure and vibrational spectral data of the molecule.

Reducing Stigma Toward Psychiatry Among Medical Students: A Multicenter Controlled Trial

Objective

To examine the effect of a novel antistigma intervention curriculum (ASIC) in reducing stigma toward psychiatry among medical students.

Methods

Medical students from 8 hospitals in central Israel were divided into intervention (n = 57) and control (n = 163) arms. The students completed the 30-item Attitudes Toward Psychiatry (ATP-30) and the Attitudes Toward Mental Illness (AMI) scales at psychiatry rotation onset and conclusion. The ASIC was designed to target prejudices and stigma through direct informal encounters with people with serious mental illness (SMI) during periods of remission and recovery. Supervised small-group discussions followed those encounters to facilitate processing of thoughts and emotions that ensued and to discuss salient topics in psychiatry. The study was conducted between November 2017 and July 2018.

Results

Significant between-group differences were found at endpoint for attitudes toward psychiatry and psychiatric patients (P < .001). Although changing attitudes toward psychiatry as a career choice was not part of the ASIC, a significant between-group difference emerged by endpoint (P < .001).

Conclusions

Implementation of an ASIC that includes contact with individuals with lived SMI experience followed by supervised small-group discussions is effective in reducing stigma in medical students' perceptions of people with mental illness and psychiatry. Further evaluation is warranted with regard to the long-term destigmatizing effects of an ASIC.

Trial Registration

ClinicalTrials.gov identifier: NCT03907696.

Multicentre validation of a microRNA-based assay for diagnosing indeterminate thyroid nodules utilising fine needle aspirate smears

AIMS

The distinction between benign and malignant thyroid nodules has important therapeutic implications. Our objective was to develop an assay that could classify indeterminate thyroid nodules as benign or suspicious, using routinely prepared fine needle aspirate (FNA) cytology smears.

METHODS

A training set of 375 FNA smears was used to develop the microRNA-based assay, which was validated using a blinded, multicentre, retrospective cohort of 201 smears. Final diagnosis of the validation samples was determined based on corresponding surgical specimens, reviewed by the contributing institute pathologist and two independent pathologists. Validation samples were from adult patients (≥18 years) with nodule size >0.5 cm, and a final diagnosis confirmed by at least one of the two blinded, independent pathologists. The developed assay, RosettaGX Reveal, differentiates benign from malignant thyroid nodules, using quantitative RT-PCR.

RESULTS

Test performance on the 189 samples that passed quality control: negative predictive value: 91% (95% CI 84% to 96%); sensitivity: 85% (CI 74% to 93%); specificity: 72% (CI 63% to 79%). Performance for cases in which all three reviewing pathologists were in agreement regarding the final diagnosis (n=150): negative predictive value: 99% (CI 94% to 100%); sensitivity: 98% (CI 87% to 100%); specificity: 78% (CI 69% to 85%).

CONCLUSIONS

A novel assay utilising microRNA expression in cytology smears was developed. The assay distinguishes benign from malignant thyroid nodules using a single FNA stained smear, and does not require fresh tissue or special collection and shipment conditions. This assay offers a valuable tool for the preoperative classification of thyroid samples with indeterminate cytology.

A vibrational spectroscopy study on anserine and its aqueous solutions

In this study based on vibrational spectroscopic measurements and Density Functional Theory (DFT), we aimed for a reliable interpretation of the IR and Raman spectra recorded for anserine in the solid phase and water (H2O) and heavy water (D2O) solutions. Initial DFT calculations at the B3LYP/6-31G(d) searched possible conformers of the anserine zwitterion using a systematic conformational search. The corresponding equilibrium geometrical parameters and vibrational spectral data were determined for each of the stable conformers (in water) by the geometry optimization and hessian calculations performed at the same level of theory using the polarized continuum model (PCM). The same calculations were repeated to determine the most energetically preferred dimer structure for the molecule and the associated geometry, force field and vibrational spectral data. The harmonic force constants obtained from these calculations were scaled by the Scaled Quantum Mechanical Force Field (SQM) method and then used in the calculation of the refined wavenumbers, potential energy distributions, IR and Raman intensities. These refined theoretical data, which confirm the zwitterion structure for anserine in the solid phase or aqueous solvents, revealed the remarkable effects of intermolecular hydrogen bonding on the structural properties and observed IR and Raman spectra of this molecule.

Comparison of body mass index and body surface area as outcome predictors in patients with systolic heart failure

BACKGROUND

We investigated whether the 'obesity paradox' in heart failure (HF) is influenced by common confounders, and assessed if body surface area (BSA) may correlate more closely than body mass index (BMI) with prognosis.

METHODS

We studied 630 systolic HF patients at their initial visit to the HF clinic. Body size was measured by BMI and BSA. The association between body indices and mortality was assessed by Cox proportional-hazard analyses.

RESULTS

There were 248 deaths during mean follow-up of 39 months. A progressive inverse association of BMI and BSA tertiles (T1-T3) with mortality risk was observed (for BSA: T3, reference, T2, hazard ratio [HR] 1.41, 95% confidence interval [CI] 1.01-1.95, p = 0.04 and T1, HR = 1.78, 95% CI 1.29-2.45, p < 0.001; for BMI: T3, reference, T2, HR = 1.29, 95% CI 0.92-1.79, p = 0.13 and T1, HR = 1.66, 95% CI 1.21-2.27, p = 0.002). The obesity paradox was attenuated after multivariate adjustment, and did not persist after adjustment for age alone (for BMI: T3, reference, T2, HR = 1.13, 95% CI 0.81-1.58, p = 0.47; T1, HR = 1.30, 95% CI 0.94-1.80, p = 0.12; for BSA: T3, reference, T2, HR = 0.96, 95% CI 0.68-1.35, p = 0.82; T1, HR = 1.15, 95% CI 0.82-1.63, p = 0.42).

CONCLUSIONS

BSA provides prognostic information similar to BMI in systolic HF. However, the obesity paradox of both BMI and BSA in HF may be confounded by the younger age of the obese patients.

Relation of reduced expression of MiR-150 in platelets to atrial fibrillation in patients with chronic systolic heart failure

Atrial fibrillation (AF) is associated with poor prognosis in patients with heart failure (HF). Although platelets play an important role in rendering a prothrombotic state in AF, the exact mechanism by which the effect is mediated is still debated. MicroRNAs (miRNAs), which have been shown to be involved in a variety of cardiovascular conditions, are abundant in platelets and in a cell-free form in the circulation. In the present study, we performed a genome-wide screen for miRNA expression in platelets of patients with systolic HF and in controls without cardiac disease, in pursuit of specific miRNAs that are associated with the presence of AF. MiRNA expression was measured in platelets from 50 patients with systolic HF and 50 controls, of which, samples from 41 patients with HF and 35 controls were used in the final analysis because of a quality control process. MiR-150 expression was 3.2-fold lower (p = 0.0003) in platelets of patients with HF with AF relative to those without AF. A similar effect was seen in serum samples from the same patients, in which miR-150 levels were 1.5-fold lower (p = 0.004) in patients with HF with AF. Furthermore, the serum levels of miR-150 were correlated to platelet levels in patients with AF (r = 0.65, p = 0.0087). In conclusion, miR-150 expression levels in platelets of patients with systolic HF with AF are significantly reduced and correlated to the cell-free circulating levels of this miRNA.

The role of microRNA profiling in prognosticating progression in Ta and T1 urinary bladder cancer

OBJECTIVE

To analyze microRNA profile in Ta and T1 urinary bladder cancers in combination and separately and to relate this to the risk of later developing higher-stage disease.

MATERIALS AND METHODS

Formalin-fixed, paraffin-embedded samples of 44 Ta and 42 T1 bladder cancers representing cases with and without stage progression during follow-up were collected and microRNA expression levels were measured by microarray analysis.

RESULTS

In a comparison between the progressors and controls, in the Ta/T1 group, miR-10a-5p and miR-31-5p were differentially expressed. miR-10a-5p was also correlated to time to progression (P = 0.00012). In the subgroup analysis, 3 microRNAs, miR-10a-5p, miR-31-5p, and miR-130a-3p, were differentially expressed among Ta tumors and had a fold change of more than 1.5 (P<0.038). The comparison concerning microRNA expression between the progressors and controls in category T1 cancers revealed no significant differences.

CONCLUSIONS

Profiling revealed that certain microRNAs predicted the risk of developing higher-stage disease among patients with Ta cancers. Lower miR-10a-5p expression in Ta progressing tumors indicates that this microRNA could be important for later malignant potential among this group of patients.

Predicting progression of bladder urothelial carcinoma using microRNA expression

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Recurrence and progression prediction in urothelial cancer is currently based on clinical and pathological factors: tumour grade, tumour stage, number of lesions, tumour size, previous recurrence rate, and presence of concomitant carcinoma in situ. These factors are not specific enough to predict progression and ∼50% of patients diagnosed as high risk in fact do not progress within 3 years. Patient follow-up is both expensive and unpleasant (frequent invasive cystoscopies). Molecular biomarkers, including microRNAs have been studied to provide additional prognostic information for these patients, but to date no molecular biomarker has become the 'gold standard' for patient diagnosis and follow-up. We used Rosetta Genomics' highly specific microRNA expression profiling platforms to study the prognostic role of microRNAs in bladder cancer. Using microdissection we chose specific tumour microRNAs to study in order to avoid background contamination. Tumour progression was associated with altered levels of microRNAs. In particular, high expression levels of miR-29c* were associated with a good prognosis. The study found that the use of microRNAs for determining progression and invasiveness for patients with urothelial cancer could potentially have a substantial impact on the treatment and follow-up individual patients.

OBJECTIVE

To identify microRNAs that could be useful as prognostic markers for non-muscle-invasive (NMI) bladder carcinoma.

PATIENTS AND METHODS

Formalin-fixed, paraffin-embedded samples of 108 NMI bladder carcinomas, and 29 carcinomas invading bladder muscle were collected, and microRNA expression levels were measured using microarrays. For 19 samples, microdissection was performed to compare microRNA expression between the tumour and surrounding tissue. MicroRNAs that were found to be unrelated to the tumour itself were excluded as potential prognostic markers.

RESULTS

Expression profiles identified microRNAs that were differentially expressed in NMI tumours from patients who later progressed to carcinoma invading bladder muscle compared with NMI tumours from patients that did not progress. The microRNA profile of tumours invading the bladder muscle was more similar to that of NMI tumours from patients who later progressed, than to that of the same-stage NMI tumours from patients who did not later progress. The expression level of one microRNA, miR-29c*, was significantly under-expressed in tumours that progressed and could be used to stratify patients with T1 disease into risk groups.

CONCLUSIONS

MicroRNAs can be useful biomarkers for prognosis in patients with urothelial carcinoma. In our study, expression levels of several microRNAs, including miR-29c* identified high- and low-risk groups. These biomarkers show promise for the stratification of patients with bladder cancer.

Serum levels of microRNAs in patients with heart failure

AIMS

Diagnosis and risk stratification of patients with heart failure remain a challenge. The small non-coding RNAs known as microRNAs regulate gene expression and seem to play an important role in the pathogenesis of heart failure. In the current study, we aim to characterize the levels of microRNAs in the sera of chronic systolic heart failure patients vs. controls and assess the possible correlation between elevation in the levels of specific microRNAs and clinical prognostic parameters in heart failure patients.

METHODS AND RESULTS

The levels of 186 microRNAs were measured in the sera of 30 stable chronic systolic heart failure patients and 30 controls using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The differences in microRNA levels between the two groups were characterized, and a score, based on the levels of four specific microRNAs with the most significant increase in the heart failure group (miR-423-5p, miR-320a, miR-22, and miR-92b), was defined. The score was used to discriminate heart failure patients from controls with a sensitivity and specificity of 90%. Moreover, in the heart failure group, there was a significant association between the score and important clinical prognostic parameters such as elevated serum natriuretic peptide levels, a wide QRS, and dilatation of the left ventricle and left atrium (r = 0.63, P = 3e-4; P = 0.009; P = 0.03; and P = 0.01, respectively).

CONCLUSIONS

Elevated serum levels of specific microRNAs: miR-423-5p, miR-320a, miR-22, and miR-92b, identify systolic heart failure patients and correlate with important clinical prognostic parameters.

A diagnostic assay based on microRNA expression accurately identifies malignant pleural mesothelioma

The definitive identification of malignant pleural mesothelioma (MPM) has significant clinical implications, yet other malignancies often involve the lung pleura, confounding the diagnosis of MPM. In the absence of accurate markers, MPM can be difficult to distinguish from peripheral lung adenocarcinoma and metastatic epithelial cancers. MicroRNA expression is tissue-specific and highly informative for identifying tumor origin. We identified microRNA biomarkers for the differential diagnosis of MPM and developed a standardized microRNA-based assay. Formalin-fixed, paraffin-embedded samples of 33 MPM and 210 carcinomas were used for assay development. Using microarrays, we identified microRNAs differentially expressed between MPM and various carcinomas. Hsa-miR-193-3p was overexpressed in MPM, while hsa-miR-200c and hsa-miR-192 were overexpressed in peripheral lung adenocarcinoma and carcinomas that frequently metastasize to lung pleura. We developed a standardized diagnostic assay based on the expression of these microRNAs. The assay reached a sensitivity of 100% and a specificity of 94% in a blinded validation set of 68 samples from the lung and pleura. This diagnostic assay can provide a useful tool in the differential diagnosis of MPM from other malignancies in the pleura.

Abstract 3017: MicroRNAs as prognostic indicators in gastric cancer

Background: Our ability to determine the prognosis of an individual patient with gastric cancer and thereby to select patients for adjuvant therapy is still limited. Preliminary data suggest that microRNAs may have a prognostic role in this disease. We hence decided to compare the microRNA profiles in the primary tumor of patients with recurrent and non-recurrent gastric cancer and to evaluate the prognostic impact of these molecules.

Patients and Methods: Eligible patients, who underwent curative gastrectomies between 1995 and 2005 and did not receive any pre- or postoperative adjuvant therapy, were identified from the database of the participating institutions. Total RNA was extracted from tumor formalin-fixed paraffin embedded (FFPE) samples using proprietary protocols that preserve the small RNA fraction. Initial profiling using microRNA microarrays identified potential microRNA biomarkers that can be used to predict recurrence of gastric cancer after resection. The expression of differential microRNAs, was verified by qRT-PCR.

Results: Forty-five eligible patients had adequate tumor content and microRNA expression data and were included in the analysis. Of these, 14 (31%) experienced recurrence of disease within three years from surgery (“bad prognosis” group) and 31 (69%) did not (“good prognosis” group). Advanced pathological stage and extensive surgical procedure correlated with bad prognosis. Signal levels of three microRNAs were found to be significantly differentially expressed in tumors from patients with good prognosis vs. patients with bad prognosis. High expression of each of these microRNAs was associated with significantly poorer prognosis for both recurrence and survival. Proprietary microRNA qRT-PCR showed a high correlation to microarrays and similar separation into prognosis groups based on microRNA expression.

Conclusion: We identified a set of microRNAs whose high expression was predictive of tumor recurrence and poor prognosis in patients with gastric cancer. This finding provides a basis for a novel tool for risk stratification in this disease and allows further insight into its pathogenesis. Based on these results, a validation study, on a larger and independent cohort of patients, is planned.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3017.

Circulating microRNAs as potential blood-based biomarkers for detection of colorectal cancer

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Background: Colorectal cancer (CRC) is one of the leading causes of cancer death worldwide. While there is a strong correlation between stage and prognosis in this disease, current screening methods for CRC have significant limitations, and newer technological approaches are desired. Circulating nucleic acids in body fluids have been studied as a source for diagnostic information and for cancer screening, yet the potential of microRNAs, a family of small non-coding regulatory RNAs, has not yet been thoroughly explored. Here we investigated the utility of microRNAs as potential serum biomarkers for early detection of CRC. Methods: We developed protocols for extracting and quantifying microRNA levels in serum. Serum levels of more than 350 microRNAs were measured using qRT-PCR on samples from 10 healthy controls and 10 CRC patients. Most microRNAs showed consistent levels across different individuals. A subset of microRNAs had significant differences in abundance between the two groups and was studied on a larger cohort of 118 patients and controls. Results: We initially identified a subset of microRNAs that showed significant differential abundance between sera of CRC patients and controls. Measuring the serum levels of 22 microRNAs on a cohort of 118 patients and controls, we showed that levels of circulating microRNAs can be very informative in the identification of CRC. Conclusions: The results demonstrate the potential of the microRNA processing and analysis methods that we developed. Certain microRNAs were found in different amounts in sera of CRC patients compared to healthy controls. Thus, circulating microRNAs represent promising candidates for diagnostic biomarkers in CRC.

[Table: see text]

Serum microRNAs are promising novel biomarkers

Background

Circulating nucleic acids (CNAs) offer unique opportunities for early diagnosis of clinical conditions. Here we show that microRNAs, a family of small non-coding regulatory RNAs involved in human development and pathology, are present in bodily fluids and represent new effective biomarkers.

Methods and Results

After developing protocols for extracting and quantifying microRNAs in serum and other body fluids, the serum microRNA profiles of several healthy individuals were determined and found to be similar, validating the robustness of our methods. To address the possibility that the abundance of specific microRNAs might change during physiological or pathological conditions, serum microRNA levels in pregnant and non pregnant women were compared. In sera from pregnant women, microRNAs associated with human placenta were significantly elevated and their levels correlated with pregnancy stage.

Conclusions and Significance

Considering the central role of microRNAs in development and disease, our results highlight the medically relevant potential of determining microRNA levels in serum and other body fluids. Thus, microRNAs are a new class of CNAs that promise to serve as useful clinical biomarkers.

Serum microRNAs are promising novel biomarkers

BACKGROUND

Circulating nucleic acids (CNAs) offer unique opportunities for early diagnosis of clinical conditions. Here we show that microRNAs, a family of small non-coding regulatory RNAs involved in human development and pathology, are present in bodily fluids and represent new effective biomarkers.

METHODS AND RESULTS

After developing protocols for extracting and quantifying microRNAs in serum and other body fluids, the serum microRNA profiles of several healthy individuals were determined and found to be similar, validating the robustness of our methods. To address the possibility that the abundance of specific microRNAs might change during physiological or pathological conditions, serum microRNA levels in pregnant and non pregnant women were compared. In sera from pregnant women, microRNAs associated with human placenta were significantly elevated and their levels correlated with pregnancy stage.

CONCLUSIONS AND SIGNIFICANCE

Considering the central role of microRNAs in development and disease, our results highlight the medically relevant potential of determining microRNA levels in serum and other body fluids. Thus, microRNAs are a new class of CNAs that promise to serve as useful clinical biomarkers.

Early autonomic malfunction in normotensive individuals with a genetic predisposition to essential hypertension

One of the primary pathologies associated with hypertension is a complex autonomic dysfunction with evidence of sympathetic hyperactivity and/or vagal withdrawal. We investigated the possibility for early detection of essential hypertension on the basis of the analysis of heart rate (HR) and blood pressure fluctuations, which reflect autonomic control. Young adult normotensive offspring of one hypertensive parent (KHT; n = 12) and normotensive offspring of two normotensive parents (YN; n = 14) participated in this study. ECG, continuous blood pressure, and respiration were recorded during steady-state conditions and under various autonomic challenges. Time-frequency decomposition of these signals was performed with the use of a continuous wavelet transform. The use of the wavelet transform enables the extension of typical HR variability analysis to non-steady-state conditions. This time-dependent spectral analysis of HR allows time-dependent quantification of different spectral components reflecting the sympathetic and parasympathetic activity during rapid transitions, such as an active change in posture (CP). During an active CP from the supine to standing position, KHT demonstrated a significantly greater increase in the low-frequency fluctuations in HR than YN, indicating enhanced sympathetic involvement in the HR response to CP, and a reduced alpha-index, indicating decreased baroreceptor sensitivity. On recovery from handgrip, vagal reactivation was more sluggish in KHT. These results indicate the early existence of malfunctions in both branches of autonomic control in individuals at increased risk of hypertension.

Emotional and cognitive factors in the borderline profile

Profiles of ego functions of borderline patients are studied. Three ego functions were found to be significantly more disturbed: reality testing, object relations, and defense mechanisms. Further analysis of these and their subfunctions reveals a significant difference between emotional and cognitive factors. Emotional-internal functions are the more disturbed. This consistent difference illuminates the style of functioning of borderline patients.

Turbulent Flow of Dilute Aqueous Polymer Solutions

This paper summarizes some of the research into the effect of polymer additives on turbulent shear flow, which was conducted at the University of Liverpool between October, 1964, and October, 1966. The paper contains a brief description of the research together with a summary of the principal results and conclusions. The present work was devoted to a detailed examination of the mechanism of a particular flow by gathering information on friction drag, velocity distribution, concentration distribution, and correlation with Reynolds number and polymer concentration level. The particular flow chosen was the fully developed turbulent flow in a 2-in-dia pipe of Polyox WSR-301 solutions. A maximum drag reduction of 71 percent was obtained at a Reynolds number of 1.5 × 105 for solutions having polymer concentration of 10 weight parts per million. The drag reduction effect occurred only above some “critical” Reynolds number which was independent of concentration. The polymer additives were found to influence the flow in the neighborhood of a solid boundary. In this zone of the flow, the eddy viscosity was found to be much lower than that of water. In the absence of a boundary, as in free jet flow, the polymer additives had no effect on the flow characteristics. The experiments showed for the first time that the polymer molecules were uniformly distributed across the pipe diameter under all turbulent flow conditions investigated. A method of determining polymer concentration was devised for this purpose.