Adjunctive therapy in treatment for head and neck cancer.

Improvement in tumor-free intervals and cure rates of patients with cancer of the head and neck will almost certainly come from utilization of more than one type of treatment in the same patient. For example, in treatment for formidable lesions this might take the form of a short course of preoperative chemotherapy followed by surgery. Postoperative chemotherapy might then be employed in preoperative responders, with the addition of radiation according to the usual postoperative indications. Specific or nonspecific immunotherapy might be used on a long-term basis, preoperatively and postoperatively. In selected patients, utilization of multiple modalities early in a careful long-term plan may bring improvement over current results from employment of adjuvant measures only after recurrence or metastatic spread is clinically obvious.     

Myasthenia gravis-associated antibodies in asymptomatic thymoma

Serum antibodies associated with myasthenia gravis were evaluated before and after therapy in an asymptomatic patient having a malignant thymoma. The case illustrates that myasthenia-associated antibodies may also be useful as a tumor marker of thymoma in the work-up of mediastinal masses, in evaluating therapy of thymoma, and possibly in detecting recurrence of thymoma and potential for developing myasthenia gravis.     

Chronic low-level lead toxicity in the rat: III. An integrated assessment of long-term toxicity with special reference to the kidney

Male and female rats whose mothers had been exposed to Pb before and during pregnancy and lactation at exposure levels of 0, 0.5, 5, 25, 50, and 250 ppm Pb as Pb-acetate in drinking water were continued on the respective regimens for 6 or 9 months. Body weights of males and females were not significantly different from controls at 6 months of age; however, female body weights were significantly decreased at 250 ppm at 9 months of age. In males at 9 months of age, spleen weights were significantly increased at 250 ppm Pb and kidney weights were increased at 0.5 ppm Pb and above; in females the liver, pituitary, and heart weights were affected at 250 ppm Pb. No significant Pb effects were found in sperm counts or sperm morphology, hematology profiles, or serum chemistries. Blood, brain, femur, and kidney Pb levels as well as urinary ALA excretion were all significantly dose related. Histopathological lesions were noted in the spleen (250 ppm) and in the kidney as evidenced by cytomegaly/karyomegaly (beginning at 5 ppm in males; 25 ppm in females), nuclear inclusion body formation and increased numbers of iron-positive granules within renal proximal tubule cells. These effects were more marked after 9 months exposure. Ultrastructural studies revealed mitochondrial swelling and the presence of increased numbers of lysosomes within renal proximal tubule cells. Energy-dispersive X-ray microanalysis, performed on adjacent sections, showed the highest intracellular Pb concentrations in nuclear inclusion bodies within renal proximal tubule cells. Inhibition of renal mitochondrial respiration for both succinate and NAD-linked substrates was found in 50- and 250-ppm Pb exposure groups at 9 months but not at 6 months. Mitochondrial δ-aminolevulinic acid synthetase and ferrochelatase, but not δ-aminolevulinic dehydratase, were also found to be inhibited at these Pb levels at 9 months. The lowest exposure level resulting in a detectable effect of Pb (cytomegaly/karyomegaly in renal proximal tubule cells) was 5 ppm associated with a median blood Pb concentration of 11 μg/dl.     

IMPORTANCE OF ANTIDIURETIC PROPERTIES OF VASOPRESSIN IN EXPERIMENTAL RENAL HYPERTENSION

1. Homozygous Brattleboro rats with hereditary hypothalamic diabetes insipidus (DI) developed one-kidney, one-clip (1K–1C) and two-kidney, one-clip (2K–1C) Goldblatt renal hypertension. 2. However, the systolic blood pressure (SBP) in 1K–1C Brattleboro rats was significantly lower than in non-DI hypertensive 1K–1C Long-Evans (LE) rats. 3. Treatment with the synthetic antidiuretic analogue of vasopressin, DDAVP (l-desamino-8-D-arginine vasopressin), increased the SBP in the DI rats to the same level as in 1K–1C Long-Evans. This elevation of SBP was associated with increased extracellular fluid volume in the DI rats after DDAVP. 4. The results suggest that vasopressin is not essential for the development of renal hypertension but the absolute levels of blood pressure achieved in 1K–1C hypertension are volume-dependent and thus influenced by the water-retaining properties of vasopressin.     

Mycobacterium marinum infections acquired from tropical fish tanks

Mycobacterium marinum is reported for the first time in New Zealand. Three cases of infection on the hands of tropical fish fanciers are described with details of treatment. Probable sources of the organism were investigated and possible explanations for its presence in New Zealand are discussed.