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Background Pulmonary metastases in papillary thyroid carcinoma have two common presentations—micro/miliary (MM) and macronodular metastases (MN). The mainstay of treatment, posttotal thyroidectomy, is multiple radioactive iodine ablations (RAIA) every 6 to 12 months. Response assessment is determined by decline in stimulated serum thyroglobulin levels (sTg), disease regression on chest x-ray (CXR), computed tomography thorax, or whole body iodine scintigraphy (TWBS). Aim This study aims to assess the difference in response to RAIA based on the pattern of presentation. Methodology Retrospective analysis of patients from January 2008 to July 2017 was done. Patients with pulmonary metastases treated with RAIA (3700MBq per therapy as opposed to theAmerican Thyroid Association recommendation of 7400MBq per therapy) and a minimum follow-up of 8 months were included. The initial and the final sTg, TWBS, and CXR were analyzed for both groups. Final outcome in terms of complete response, disease regression, static disease, and disease progression was determined. Results Of the total of 1,793 patients, 71 were included. There were 43 females and 28 males. The median age was 39 years and the range was 14 to 79 years. Forty-five (63.3%) patients had MM and 26 (36.6%) patients had MN disease. The average number of therapies was three and maximum follow-up period was 15 years. Of the 45 MM patients, 1 had progression, 7 were static, 23 had regression, and 14 had complete response. Of the 26 MN patients, 22 had progression, 2 were static, 1 had regression, and 1 had complete response. Conclusion MM metastases, when compared with MN disease, respond to RAIA with a better outcome. In addition to achieving comparable response with a lower dose per therapy, there were no radiation-related long-term complications reported. [ABSTRACT FROM AUTHOR]

The mechanism of the epimerization of cis-1,2,3-trisubstituted tetrahydro-[beta]-carbolines into the trans isomers via a potential carbocationic intermediate at C(1) is studied. The analysis of the pathway involved in C(1)-N(2) bond cleavage has provided evidence of the effects of charge at the proposed site of the carbocationic intermediate.

Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation is currently recommended for the estimation of glomerular filtration rate (GFR). This retrospective study aimed to evaluate the correlation between creatinine and cysC-based estimated GFRs and measured GFR in healthy adults. Consecutive healthy adults who were accepted as voluntary kidney donors at our center between January 2008 and December 2012 were included in the study. The 336 individuals who comprised the study population had a mean age of 41.6 ± 11.8 years, male:female ratio 1:1.7, mean creatinine 0.9 ± 0.1 mg/dl, and mean cysC 0.8 ± 0.1 mg/dl. Mean measured GFR by Tc-99m diethylenetriaminepentaacetic acid using Gates method was 98.4 ± 21.2 ml/min/1.73 m2. The mean ± standard deviation of eGFRs by various formulae were as follows: Cockcroft--Gault (CG) = 88.1 ± 15.9 ml/min/1.73 m2, Modification of Diet in Renal Disease (MDRD) = 78 ± 14.7 ml/min/1.73 m2, CKD-EPI creatinine = 88.1 ± 15.5 ml/min/1.73 m2, CKD-EPI cysC = 97 ± 19.9 ml/min/1.73 m2, CKD-EPI creatinine-cysC (CKD-EPI cr-cysC) = 92.5 ± 14.1 ml/min/1.73 m2. The CKD-EPI cr-cysC equation had the highest accuracy, with 43% and 72% of values lying within ±10% and ±20% of the measured GFR, respectively. Bland--Altman analyses for levels of agreement showed least bias with CKD-EPI cysC overall and among females, while among males, CKD-EPI creatinine equation had the least bias. The CKD-EPI equation showed a higher performance than the MDRD and CG equation in GFR estimation of a healthy population. Among CKD-EPI equations, CKD-EPI cr-cysC had the highest accuracy and CKD-EPI cysC the least bias. [ABSTRACT FROM AUTHOR]

This paper proposes a predictive techno-economic analysis in terms of voltage stability and cost using regression-based machine learning (ML) models and effectiveness of the analysis is validated. Predictive analysis of a power system is proposed to address the need for faster and accurate analyses that would aid in the operation and control of modern power system. Several methods of analyses including metaheuristic optimization algorithms, artificial intelligence techniques and machine learning algorithms are being developed and used. Predictive ML models for two modified IEEE 14-bus and IEEE-30 bus systems, integrated with renewable energy sources (solar and wind) and reactive power compensative device (STATCOM) are proposed and developed with features that include hour of the day, solar irradiation, wind velocity, dynamic grid price and system load. An hour-wise input database for the model development is generated from monthly average data and hour-wise daily curves with normally distributed standard deviations. The data feasibility tests and output database generation is performed using MATLAB. Linear and higher order polynomial regression models are developed for the 8760hr database using Python 3.0 in JupyterLab and a best-fit predictive ML model is identified by analysing the coefficients of determination. The voltage stability and cost predictive ML models were tested for a 24hr input profile. The results obtained and the comparison with the expected values are furnished. Prediction of the outputs for the test data validate the accuracy of the developed model.

The present study was undertaken to shed light on the mechanism of the epimerization of cis- 1,2,3- trisubstituted tetrahydro-β-carbolines into the trans isomers via a potential carbocationic intermediate at C(1). In order to study the pathway involved in C(1)-N(2) bond cleavage, the electronic character of the carbon atom at C-1 was altered by substitution of electron-rich and electron-poor phenyl rings at this position. This provided direct evidence of the effects of charge at the proposed site of the carbocationic intermediate. In this regard, a diverse set of l-(phenyl substituted)-2-benzyl-3-ethoxycarbonyl-l,2,3,4- tetrahydro-β-carbolines has been synthesized via the Pictet-Spengler reaction by condensation of L-tryptophan derivatives with electron-poor and electron-rich aromatic aldehydes. The epimers involved in the isomerization mechanism were investigated by dynamic 1H and 13C NMR spectroscopic and X-ray crystallographic analyses. The kinetic studies, which involved conversion of cis diastereomers into their trans counterparts, were carried out in dilute TFA/CH2Cl2. The 1-(4-methoxyphenyl) cis diastereomer epimerized at a much faster rate into the corresponding trans diastereomer than the related 1-(4-nitrophenyl) cis diastereomer epimerized. These observations provide support for the carbocationic intermediate in the C(l)-N(2) scission process. The understanding of this epimerization process is of importance when Pictet-Spengler reactions are carried out under acidic conditions during the synthesis of indole alkaloids. [ABSTRACT FROM AUTHOR]

A selective and direct access to secondary amines is reported by reductive mono-N-alkylation of primary amines in the presence of Ti(i-PrO)[sub4] and NaBH[sub4]. Secondary amines are obtained exclusively from a set of carbonyl compounds and primary amines, demonstrating high chemoselectivity toward reductive mono-N- alkylation. [ABSTRACT FROM AUTHOR]

A diverse set of N-methyl secondary amines are obtained in high yields by an expedient reductive alkylation of commercially available methanolic methylamine. [ABSTRACT FROM AUTHOR]

αβ T-cell receptors (TCRs) engage antigens using complementarity-determining region (CDR) loops that are either germ line-encoded (CDR1 and CDR2) or somatically rearranged (CDR3). TCR ligands compose a presentation platform (major histocompatibility complex (MHC)) and a variable antigenic component consisting of a short "foreign" peptide. The sequence of events when the TCR engages its peptide-MHC (pMHC) ligand remains unclear. Some studies suggest that the germ line elements of the TCR engage the MHC prior to peptide scanning, but this order of binding is difficult to reconcile with some TCR-pMHC structures. Here, we used TCRs that exhibited enhanced pMHC binding as a result of mutations in either CDR2 and/or CDR3 loops, that bound to the MHC or peptide, respectively, to dissect the roles of these loops in stabilizing TCR-pMHC interactions. Our data show that TCR-peptide interactions play a strongly dominant energetic role providing a binding mode that is both temporally and energetically complementary with a system requiring positive selection by self-pMHC in the thymus and rapid recognition of non-self-pMHC in the periphery. [ABSTRACT FROM AUTHOR]