Tuberculosis of the thyroid gland is an extremely rare condition. Amongst 1565 cases of thyroid lesions subjected to fine needle aspiration cytology (FNAC) over a period of nine years, 18 cases (1.15 per cent) were found to have cytological features consistent with tuberculosis thyroiditis. Acid-fast bacilli were isolated in all cases. The ages of the patients ranged from 36 to 52 years with a median age of 46 years: there were 12 females and 6 males. All the patients presented with painless solitary nodules of the thyroid. Three patients had concomitant cervical lympadenopathy and four patients were known to have tuberculosis of the lungs which was being treated. Solitary nodules of the thyroid were confirmed by a thyroid scan with radioactive iodine. Fine needle aspirates from thyroid swellings showed epithelioid granulomas with necrosis in all cases. There were no false reports or complications.It is evident from this study that FNAC is an efficient way with which to detect tuberculosis of the thyroid gland.

Modern crises in implantable or indwelling blood-contacting medical devices are mainly due to the dual problems of infection and thrombogenicity. There is a paucity of biomaterials that can address both problems simultaneously through a singular platform. Taking cues from the body's own defense mechanism against infection and blood clotting (thrombosis) via the endogenous gasotransmitter nitric oxide (NO), both of these issues are addressed through the development of a layered S-nitroso-N-acetylpenicillamine (SNAP)-doped polymer with a blended selenium (Se)− polymer interface. The unique capability of the SNAP-Se-1 polymer composites to explicitly release NO from the SNAP reservoir as well as generate NO via the incorporated Se is reported for the first time. The NO release from the SNAP-doped polymer increased substantially in the presence of the Se interface. The Se interface was able to generate NO in the presence of S-nitrosoglutathione (GSNO) and glutathione (GSH), demonstrating the capability of generating NO from endogenous S-nitrosothiols (RSNO). Scanning electron microscopyenergy dispersive spectroscopy (SEM-EDS) traced distribution of elemental Se nanoparticles on the interface and the surface properties were evaluated by surface wettability and roughness. The SNAP-Se-1 efficiently inhibited the growth of bacteria and reduced platelet adhesion while showing minimal cytotoxicity, thus potentially eliminating the risks of systemic antibiotic and blood coagulation therapy. The SNAP-Se-1 exhibited antibacterial activity of ∼2.39 and ∼2.25 log reductions in the growth of clinically challenging adhered Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. SNAP-Se-1 also significantly reduced platelet adhesion by 85.5% compared to corresponding controls. A WST-8-based cell viability test performed on NIH 3T3 mouse fibroblast cells provided supporting evidence for the potential biocompatibility of the material in vitro. These results highlight the prospective utility of SNAP-Se-1 as a blood-contacting infection-resistant biomaterial in vitro which can be further tuned by application specificity.

Phenols and quinols participate in both proton transfer and electron transfer processes in nature either in distinct elementary steps or in a concerted fashion. Recent investigations using synthetic heme/Cu models and iron porphyrins have indicated that phenols/quinols can react with both ferric superoxide and ferric peroxide intermediates formed during O 2 reduction through a proton coupled electron transfer (PCET) process as well as via hydrogen atom transfer (HAT). Oxygen reduction by iron porphyrins bearing covalently attached pendant phenol and quinol groups is investigated. The data show that both of these can electrochemically reduce O 2 selectively by 4e − /4H + to H 2 O with very similar rates. However, the mechanism of the reaction, investigated both using heterogeneous electrochemistry and by trapping intermediates in organic solutions, can be either PCET or HAT and is governed by the thermodynamics of these intermediates involved. The results suggest that, while the reduction of the Fe III −O 2 − species to Fe III −OOH proceeds via PCET when a pendant phenol is present, it follows a HAT pathway with a pendant quinol. In the absence of the hydroxyl group the O 2 reduction proceeds via an electron transfer followed by proton transfer to the Fe III −O 2 − species. The hydrogen bonding from the pendant phenol group to Fe III −O 2 − and Fe III −OOH species provides a unique advantage to the PCET process by lowering the inner-sphere reorganization energy by limiting the elongation of the O−O bond upon reduction.

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