Occult Thyroid Carcinoma with Cervical Lymph Node Metastasis: A Rare Case Report.

Cervical lymph node metastasis is one of the most common clinical presentations of papillary thyroid carcinoma (PTC). Occult thyroid carcinoma is described as absence of primary tumour or with presence of microcarcinoma in thyroid with cervical lymph node metastasis. Frequency of occult thyroid cancer has decreased due to developments in imaging and improved accuracy of histological examinations.

Trapping an Elusive Fe(IV)-Superoxo Intermediate Inside a Self-Assembled Nanocage in Water at Room Temperature.

Molecular cavities that mimic natural metalloenzymes have shown the potential to trap elusive reaction intermediates. Here, we demonstrate the formation of a rare yet stable Fe(IV)-superoxo intermediate at room temperature subsequent to dioxygen binding at the Fe(III) site of a (EtN)[Fe(Cl)(bTAML)] complex confined inside the hydrophobic interior of a water-soluble PdL nanocage. Using a combination of electron paramagnetic resonance, Mössbauer, Raman/IR vibrational, X-ray absorption, and emission spectroscopies, we demonstrate that the cage-encapsulated complex has a Fe(IV) oxidation state characterized by a stable S = 1/2 spin state and a short Fe-O bond distance of ∼1.

Comparative Evaluation of Extrusion of Apical Debris and Irrigant using Three Different Rotary Systems with Conventional Irrigation Methods - An Study.

Aim: The present study aimed to compare and evaluate debris and irrigant extrusion from curved root canals using different rotary systems.

Materials And Methods: 30 single-rooted mandibular canines were used in this study. The crown was decoronated, working length and initial apical diameter were established.

CO Activation with Manganese Tricarbonyl Complexes through an H-Atom Responsive Benzimidazole Ligand.

Herein, we report the synthesis and characterization of two manganese tricarbonyl complexes, Mn (HL)(CO) Br (1 a-Br) and Mn (MeL)(CO) Br (1 b-Br) (where HL=2-(2'-pyridyl)benzimidazole; MeL=1-methyl-2-(2'-pyridy)benzimidazole) and assayed their electrocatalytic properties for CO reduction. A redox-active pyridine benzimidazole ancillary ligand in complex 1 a-Br displayed unique hydrogen atom transfer ability to facilitate electrocatalytic CO conversion at a markedly lower reduction potential than that observed for 1 b-Br. Notably, a one-electron reduction of 1 a-Br yields a structurally characterized H-bonded binuclear Mn(I) adduct (2 a') rather than the typically observed Mn(0)-Mn(0) dimer, suggesting a novel method for CO activation.

A first glance into mixed phosphine-stibine moieties as protecting ligands for gold clusters.

Atomically precise gold clusters have attracted considerable research interest as their tunable structure-property relationships have resulted in widespread applications, from sensing and biomedicine to energetic materials and catalysis. In this article, the synthesis and optical properties of a novel [Au(SbP)][PF] cluster are reported. Despite the lack of spherical symmetry in the core, the cluster shows exceptional thermal and chemical stability.

Phytoremediation of toxic chemicals in aquatic environment with special emphasis on duckweed mediated approaches.

The discharge of toxic chemicals into water bodies and their linked detrimental effects on health is a global concern. Phytoremediation, an environment-friendly plant-based technology, has gained intensive interest over the last decades. For the aquatic phytoremediation process, the commonly available duckweeds have recently attracted significant attention due to their capacity to grow in diverse ecological niches, fast growth characteristics, suitable morphology for easy handling of biomass, and capacity to remove and detoxify various potential toxic elements and compounds.

Crystal Structure and Optical Properties of a Chiral Mixed Thiolate/Stibine-Protected Au Cluster.

We report the first example of a chiral mixed thiolate/stibine-protected gold cluster, formulated as Au(S-Adm)(SbPh)Br (where S-Adm = 1-adamantanethiolate). Single crystal X-ray crystallography reveals the origin of chirality in the cluster to be the introduction of the rotating arrangement of Au(S-Adm) and Au(S-Adm) staple motifs on an achiral Au core and the subsequent capping of the remaining gold atoms by SbPh and Br ligands. Interestingly, the structure and properties of this new Au cluster are found to be different from other reported achiral Au clusters and the only other stibine-protected [Au(SbPh)Cl] cluster.

Possible involvement of agmatine in neuropharmacological actions of metformin in diabetic mice.

The risk of psychiatric and neurological disorders is significantly higher in patients with diabetes mellitus. Diabetic patients are more susceptible to depression, anxiety and memory impairment as compared with non-diabetic individuals. Metformin, a biguanide used for the management of type 2 diabetes mellitus (T2DM), promotes neurogenesis, enhances spatial memory function and protects the brain against oxidative imbalance beyond its effect on glucose metabolism.

Effect of Curing on Micro-Physical Performance of Polypropylene Fiber Reinforced and Silica Fume stabilized Expansive Soil Under Freezing Thawing Cycles.

This study presents the micro-physical investigation of polypropylene (PP) fiber-reinforced, and silica fume (SF) stabilized expansive soil (BC) subgrade. The coupling effect of soil, PP fiber, and SF has been evaluated under the freezing-thawing (F-T) cycle to assess the durability of treated BC Soil. The curing method and duration staggeringly influence the strength of SF treated BC soil; therefore, three different curing method, i.

Exploring the sampling rate effect on digital time of flight response for fast scintillator detectors.

A systematic study is conducted to understand the digital time of flight (TOF) response for a pair of fast scintillator detectors; BaF-LaBr, BaF-BC501A, and LaBr-BC501A respectively. Coincidence signals from each detector pair, irradiated by Na source, are acquired by LeCroy HDO5000A digital oscilloscope. While operating the oscilloscope at 2.

Selective photocatalytic hydroxylation and epoxidation reactions by an iron complex using water as the oxygen source.

The iron complex [(bTAML)Fe-OH] () selectively catalyses the photocatalytic hydroxylation and epoxidation reactions of alkanes and alkenes, respectively, using water as the oxygen-atom source. Upon the oxidation of unactivated alkanes, which included several substrates including natural products, hydroxylation was observed mostly at the 3° C-H bonds with 3° : 2° selectivity up to ∼100 : 1. When alkenes were used as the substrates, epoxides were predominantly formed with high yields.

Selective C-H Bond Oxidation Catalyzed by the Fe-bTAML Complex: Mechanistic Implications.

Nonheme iron complexes bearing tetradentate N-atom-donor ligands with cis labile sites show great promise for chemoselective aliphatic C-H hydroxylation. However, several challenges still limit their widespread application. We report a mechanism-guided development of a peroxidase mimicking iron complex based on the bTAML macrocyclic ligand framework (Fe-bTAML: biuret-modified tetraamido macrocyclic ligand) as a catalyst to perform selective oxidation of unactivated 3° bonds with unprecedented regioselectivity (3°:2° of 110:1 for adamantane oxidation), high stereoretention (99%), and turnover numbers (TONs) up to 300 using mCPBA as the oxidant.

Reductive activation of O by a bioinspired Fe complex for catalytic epoxidation reactions.

Aerobic epoxidation of olefins catalyzed by iron complexes without the use of a sacrificial coreductant is unknown. We report the reductive activation of O by a bioinspired [(bTAML)Fe(HO)] (1) complex to catalyze the epoxidation of alkenes with TONs of up to 80. Spectroscopic and kinetic evidence indicates the involvement of Fe(O) as the active oxidant during the reaction.

Spectroscopic and Reactivity Comparisons of a Pair of bTAML Complexes with Fe═O and Fe═O Units.

In this report we compare the geometric and electronic structures and reactivities of [Fe(O)] and [Fe(O)] species supported by the same ancillary nonheme biuret tetraamido macrocyclic ligand (bTAML). Resonance Raman studies show that the Fe═O vibration of the [Fe(O)] complex 2 is at 798 cm, compared to 862 cm for the corresponding [Fe(O)] species 3, a 64 cm frequency difference reasonably reproduced by density functional theory calculations. These values are, respectively, the lowest and the highest frequencies observed thus far for nonheme high-valent Fe═O complexes.

Electrochemical Formation of Fe (O) and Mechanism of Its Reaction with Water During O-O Bond Formation.

A detailed electrochemical investigation of a series of iron complexes (biuret-modified tetraamido iron macrocycles Fe -bTAML), including the first electrochemical generation of Fe (O), and demonstration of their efficacy as homogeneous catalysts for electrochemical water oxidation (WO) in aqueous medium are reported. Spectroelectrochemical and mass spectral studies indicated Fe (O) as the active oxidant, formed due to two redox transitions, which were assigned as Fe (O)/Fe (OH ) and Fe (O)/Fe (O). The spectral properties of both of these high-valent iron oxo species perfectly match those of their chemically synthesised versions, which were thoroughly characterised by several spectroscopic techniques.

Electrocatalytic water oxidation by a molecular cobalt complex through a high valent cobalt oxo intermediate.

Biuret-modified tetraamidomacrocyclic cobalt complex [Co-bTAML] is shown to catalyze electrochemical water oxidation at basic pH leading to the formation of O. Electrochemical and spectroscopic studies indicate a high valent cobalt oxo intermediate isoelectronic to Co(O) as the active oxidant. The kinetic isotope effect of 8.

Synthesis of 4-piperidone Based Curcuminoids with Anti-inflammatory and Anti-Proliferation Potential in Human Cancer Cell Lines.

A series of 4-piperidone based curcuminoids were synthesized and anticancer potential of these compounds was evaluated against human myeloid leukemia (KBM5) and colon cancer (HCT116) cell lines. Their anti-inflammatory potential was determined through the down-regulation of tumor necrosis factor (TNF)-α-induced nuclear factor (NF)-κB. All compounds, except one, were found to exhibit better cytotoxicity than curcumin at 5 μM.

Mechanism of Oxygen Atom Transfer from Fe(V)(O) to Olefins at Room Temperature.

In biological oxidations, the intermediate Fe(V)(O)(OH) has been proposed to be the active species for catalyzing the epoxidation of alkenes by nonheme iron complexes. However, no study has been reported yet that elucidates the mechanism of direct O-atom transfer during the reaction of Fe(V)(O) with alkenes to form the corresponding epoxide. For the first time, we study the mechanism of O-atom transfer to alkenes using the Fe(V)(O) complex of biuret-modified Fe-TAML at room temperature.

Tuning the reactivity of Fe(V)(O) toward C-H bonds at room temperature: effect of water.

The presence of an Fe(V)(O) species has been postulated as the active intermediate for the oxidation of both C-H and C═C bonds in the Rieske dioxygenase family of enzymes. Understanding the reactivity of these high valent iron-oxo intermediates, especially in an aqueous medium, would provide a better understanding of these enzymatic reaction mechanisms. The formation of an Fe(V)(O) complex at room temperature in an aqueous CH3CN mixture that contains up to 90% water using NaOCl as the oxidant is reported here.

Homogeneous photochemical water oxidation by biuret-modified Fe-TAML: evidence of Fe(V)(O) intermediate.

Water splitting, leading to hydrogen and oxygen in a process that mimics natural photosynthesis, is extremely important for devising a sustainable solar energy conversion system. Development of earth-abundant, transition metal-based catalysts that mimic the oxygen-evolving complex of photosystem II, which is involved in oxidation of water to O2 during natural photosynthesis, represents a major challenge. Further, understanding the exact mechanism, including elucidation of the role of active metal-oxo intermediates during water oxidation (WO), is critical to the development of more efficient catalysts.

High density, multi-range analog output Versa Module Europa board for control system applications.

A new VMEDAC64, 12-bit 64 channel digital-to-analog converter, a Versa Module Europa (VME) module, features 64 analog voltage outputs with user selectable multiple ranges, has been developed for control system applications at Inter University Accelerator Centre. The FPGA (Field Programmable Gate Array) is the module's core, i.e.

Formation of a room temperature stable Fe(V)(O) complex: reactivity toward unactivated C-H bonds.

An Fe(V)(O) complex has been synthesized from equimolar solutions of (Et4N)2[Fe(III)(Cl)(biuret-amide)] and mCPBA in CH3CN at room temperature. The Fe(V)(O) complex has been characterized by UV-vis, EPR, Mössbauer, and HRMS and shown to be capable of oxidizing a series of alkanes having C-H bond dissociation energies ranging from 99.3 kcal mol(-1) (cyclohexane) to 84.

Experimental study of neuropharmacological profile of Euphorbia pulcherrima in mice and rats.

Context: Euphorbia pulcherrima (EP) belongs to the family: Euphorbiaceae and Genus: Euphorbia. Many species of Euphorbia have been reported as having beneficial properties like anticonvulsive effect, central analgesic properties, antipyretic action, central depressant action and strong sedative effect. However, little study has been done and published on EP.

Feedback on and knowledge, attitude, and skills at the end of pharmacology practical sessions.

Concern has been raised about inadequate pharmacology teaching in medical schools and the high incidence of prescribing errors by doctors in training. Modifications in pharmacology teaching have been carried out in many countries. The present study was carried out using a semi-structured questionnaire to obtain students' perceptions of their knowledge, attitudes, and skills with regard to different subject areas related to rational prescribing at the end of two-year activity-based pharmacology practical learning sessions in a private medical school in Nepal.