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Porcine epidemic diarrhea virus (PEDV) is a coronavirus (CoV) discovered in the 1970s that infects the intestinal tract of pigs, resulting in diarrhea and vomiting. It can cause extreme dehydration and death in neonatal piglets. In Asia, modified live attenuated vaccines have been used to control PEDV infection in recent years. However, a new strain of PEDV that belongs to genogroup 2a appeared in the USA in 2013 and then quickly spread to Canada and Mexico as well as Asian and European countries. Due to the less effective protective immunity provided by the vaccines against this new strain, it has caused considerable agricultural and economic loss worldwide. The emergence of this new strain increases the importance of understanding PEDV as well as strategies for inhibiting it. Coronaviral proteases, including main proteases and papain-like proteases, are ideal antiviral targets because of their essential roles in viral maturation. Here we provide a first description of the expression, purification and structural characteristics of recombinant PEDV papain-like protease 2, moreover present our finding that 6-thioguanine, a chemotherapeutic drug, in contrast to its competitive inhibition on SARS- and MERS-CoV papain-like proteases, is a noncompetitive inhibitor of PEDV papain-like protease 2., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Severe acute respiratory syndrome coronavirus (SARS-CoV) emerged in southern China in late 2002 and caused a global outbreak with a fatality rate around 10% in 2003. Ten years later, a second highly pathogenic human CoV, MERS-CoV, emerged in the Middle East and has spread to other countries in Europe, North Africa, North America and Asia. As of November 2017, MERS-CoV had infected at least 2102 people with a fatality rate of about 35% globally, and hence there is an urgent need to identify antiviral drugs that are active against MERS-CoV. Here we show that a clinically available alcohol-aversive drug, disulfiram, can inhibit the papain-like proteases (PL pro s) of MERS-CoV and SARS-CoV. Our findings suggest that disulfiram acts as an allosteric inhibitor of MERS-CoV PL pro but as a competitive (or mixed) inhibitor of SARS-CoV PL pro . The phenomenon of slow-binding inhibition and the irrecoverability of enzyme activity after removing unbound disulfiram indicate covalent inactivation of SARS-CoV PL pro by disulfiram, while synergistic inhibition of MERS-CoV PL pro by disulfiram and 6-thioguanine or mycophenolic acid implies the potential for combination treatments using these three clinically available drugs., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This is a report of ectopic thyroid tissue in the neck, associated with a nodular colloid goiter, which recurred at least three times, beginning at age 24 years, in a woman in 12 years. The ectopic tissue appeared histologically benign and was identical to that found in the thyroid gland. Scintiscans of the neck and thyroid suppression tests showed that the tissue was initially unsuppressible and presumably autonomous in its function. Our conclusion is that the most reasonable explanation for this phenomenon is the intraoperative transmission of thyroid cells, probably benign and autonomous in function, to other sites in the neck.

Invasion of chick chorioallantoic membrane (CAM) organ cultures by rat 3Y1 cells transformed by the highly oncogenic human adenovirus type 12 (3Y1/12-10 cells) was inhibited by several retinoids tested. The anti-invasive activity of the retinoids was dependent on retinoid concentration and continuous (4 d) exposure of the CAM. The 50% retinoid dose (dose effective in achieving a response in half of the organ cultures) that inhibited invasion was 0.85 micrograms/ml of retinol palmitate, 0.39 micrograms/ml of retinoic acid, or 0.16 micrograms/ml of retinol acetate. This dose was of the same order of magnitude as that which induced CAM differentiation, and was three- to fourfold less than the dose that caused cytotoxic damage of CAM. In addition, the retinoids inhibited 3Y1/12-10 cell growth by approximately 40% at levels over 10-fold higher than those needed for anti-invasion activity. The findings suggest that the anti-invasive activity of retinoids was at least partly due to direct induction of cell differentiation of the CAM host tissue.

We present two cases of myelomatous involvement of the skull. Correlative studies with routine radiography, angiography, and encephaloscintigraphy were performed. The areas of involvement of the skull were confirmed as autopsy. A mixed pattern of photon-deficient and photon-abundant lesions was noted. The clinician should be aware of such mixed patterns.

In patients with trauma to the ureter, Ga-67 accumulation may represent a urinoma rather than abscess formation. Comparison with other radiologic studies may help to confirm this diagnosis.

A new triiodothyronine (T3) radioimmunoassay kit offers simplicity of method, short incubation time, specificity, and reproducibility. 125I-labeled T3 and unknown serum (or standard) are added to alkaline buffered (pH 12.4) Sephadex G-25 columns; the T3 is freed of proteins with an alkaline buffer wash, antiserum is added, and the columns are incubated at room temperature for 2 h. "Free" hormone (i.e., unbound to antiserum) remains on the column after a second wash. The radioactivity on the column is counted and related to the total activity added. The T3 standards produced a straight line on log-logit plot; reactivity of analytical-grade thyroxine was 0.6% on weight basis; and the analytical recovery of T3 added to a T3-free serum was complete. Euthroid, hyperthyroid, and hypothyroid ranges were 0.74-2.64, 2.91-7.52, and 0-1.21 mug/liter, respectively. These values correlated well with both the clinical status of patients and with values obtained by an established radioimmunoassay method. The procedure is simply done; results may be obtained in less than 4 h.

Six cases of an unusual fibro-osseous rib lesion are presented. These six lesions were asymptomatic, and five were found incidentally as solitary hot spots on bone scans which had been performed to rule out metastatic carcinoma. One was found incidentally in a rib resected for another reason. Histologically, these painless lesions most closely resemble osteoid osteomas. This study also documents that solitary rib hot spots are almost always benign even if the patient has a primary carcinoma.