Comparison of the effects of iodine and iodide on thyroid function in humans.

Concerns have been raised over the use of iodine for disinfecting drinking water on extended space flights. Most fears revolve around effects of iodide on thyroid function. iodine (I2) is the form used in drinking-water disinfection. Risk assessments have treated the various forms of iodine as if they were toxicologically equivalent. Recent experiments conducted in rats found that administration of iodine as I- (iodide) versus I2 had opposite effects on plasma thyroid hormone levels. I2-treated animals displayed elevated thyroxine (T4) and thyroxine/triiodothyronine (T/T3) ratios, whereas those treated with I- displayed no change or reduced plasma concentrations of T4 at concentrations in drinking water of 30 or 100 mg/L. The study herein was designed to assess whether similar effects would be seen in humans as were observed in rats. A 14-d repeated-dose study utilizing total doses of iodine in the two forms at either 0.3 or 1 mg/kg body weight was conducted with 33 male volunteers. Thyroid hormones evaluated included T4, T3, and thyroid-stimulating hormone (TSH). TSH was significantly increased by the high dose of both I2 and I-, as compared to the control. Decreases in T4 were observed with dose schedules with I- and I2, but none were statistically significant compared to each other, or compared to the control. This human experiment failed to confirm the differential effect of I2 on maintenance of serum T4 concentrations relative to the effect of I- that was observed in prior experiments in rats. However, based on the elevations in TSH, there should be some concern over the potential impacts of chronic consumption of iodine in drinking water.

[Roentgen findings in spontaneous esophageal perforation (Boerhaave syndrome)]. / Röntgenbefunde bei spontaner Osophagusperforation (Boerhaave-Syndrom).

Having experienced two cases of Boerhaave's syndrome (spontaneous rupture of the oesophagus), one a 42-year-old man, the other a 76-year-old woman, who both died of complications failing operative repair, the authors undertook a survey of the literature in order to evaluate the role of radiology in the detection of this life-threatening condition. An analysis of 118 clinically and 67 radiologically well-documented cases yielded pathologic findings in chest X-rays in 90% of the cases. Hydropneumothorax was found in 51%, pneumomediastinum in 30%, isolated pleural effusion in 25%, and infiltration of the parenchyma in 14% of the patients. In all cases it was possible to demonstrate by contrast medium-filling of the oesophagus with an aqueous medium.

[Ultrasonic diagnosis of so-called "occult" testicular tumor]. / Sonographische Diagnose des sogenannten "okkulten" Hodentumors.

A 40-year old man complaining of severe pain in the right mid-abdomen, nausea and vomiting was brought to the casualty department. Sonography revealed retroperitoneal masses in the right mid-abdomen and the left lower abdomen. These masses were confirmed by computed tomography and lymphography to be lymph node metastases. In the smaller right testis, in which a tumour was not suspected, a hypoechoic region was identified, which on histological examination after orchiectomy proved to be a pure seminoma.

Cross-reactivity between the EBNA-1 p107 peptide, collagen, and keratin: implications for the pathogenesis of rheumatoid arthritis.

An unusually heavy load of Epstein-Barr virus (EBV) infection and autoimmunity to collagen are believed to be contributing factors to the pathogenesis of rheumatoid arthritis (RA). The present report presents data showing that p107, the major epitope of the EBV-encoded EBNA-1 antigen, cross-reacts with denatured collagen (DC) and keratin (K), suggesting a new likely link among RA, EBV-1, and these autoantigens. A radioimmunoassay using antigen-coated microtiter plates was used to demonstrate antibodies in sera of patients with RA and sera of healthy donors against p107, DC, and K. Specificity of the antibodies was ascertained by inhibition tests with the homologous antigens. Cross-reactivity among anti-p107, anti-DC, and anti-K antibodies was assayed by the ability of a given antigen to block the binding of nonpurified or affinity-purified antibodies to plates coated with another antigen. Most of the sera contained antibodies to all three antigens, but only anti-DC antibodies were present in higher titers in RA sera. Preincubation of sera with p107 appreciably reduced their binding to plates coated with DC or K. On the other hand, preincubation with DC (in solution or bound to Sepharose) did not result in consistent reduction of anti-p107 titers. Tests with affinity-purified antibodies revealed the existence of two antibodies populations, one of which reacted preferentially with p107, the other with DC. The cross-reactivity of the anti-p107 antibodies with DC and K suggests that such antibodies, produced by RA patients following persistent stimulation with EBV, might react in vivo with collagen (and keratin) exposed in previously damaged areas and thus reinforce the disease process.

The effect of combined treatment of HeLa cells with actinomycin D and radiation upon survival and recovery from radiation damage.

The presence of actinomycin D during irradiation of HeLa cells leads to radiosensitization under aerobic but not under hypoxic conditions. Depending on the time interval between incubation with the drug and irradiation, pre- or post-treatment with actinomycin D also increases the radiosensitivity of HeLa cells irradiation in air. Pretreatment with actinomycin D does not inhibit recovery from potentially lethal radiation damage. In split-dose experiments, recovery from sublethal radiation damage was not impaired by the drug if present during the entire fractionation interval or if it was given as a short exposure after the first radiation dose.