ASPECTS OF SURGICAL TREATMENT FOR MALIGNANT MELANOMA: THE PLACE OF BIOPSY AND WIDE EXCISION

Blopsy of melanoma is discussed in respect of the operator, the adequacy of blopsy, and the time delay till wide excislon; statistics are taken from a series of 509 patients with this disease who had their definitive surgery and review at the Peter MacCallum Clinic between 1954 and 1973. Wide excision is described in respect of its origins and its proponents, and discussion draws on appropriate material from the series.     

A biochemical investigation of amyloidosis in the duck

A field case of amyloidosis in a laying flock of white Pekin ducks was investigated biochemically. The following biochemical parameters were found to differ from those of a healthy flock matched for genetic background and age: whole blood glucose, serum uric acid, calcium, magnesium, sodium, GOT and AP.     

Synthesis of 11 beta,13 beta- and 13 beta,16 beta-propano steroids: probes of hormonal activity.

Syntheses of 11 beta,13 beta- and 13 beta,16 beta-propano derivatives of 17 alpha-ethynyl-17 beta-hydroxygon-4-en-3-one are described. The 13 beta,16 beta bridge was constructed by intramolecular alkylation of the C-16 enolate anion from 3-methoxy-13 beta-[3'-(tosyloxy)propyl]gona-3,5-dien-17-one, the latter being obtained via Birch reduction of both aryl groups of 17 beta-hydroxy-3-methoxy-13 beta-(3'-phenoxypropyl)gona-1,3,5(10),8-tetraene (1). The 11 beta,13 beta bridge was constructed by Prins cyclization of 17 beta-acetoxy-3-methoxy-13 beta-(3'-oxopropyl)gona-1,3,5(10),9(11)-tetraene, itself obtained via Birch reduction of only the side-chain aryl group of 1. Binding affinities of certain of these compounds and substituted 13 beta-propyl derivatives of 17 alpha-ethynyl-17 beta-hydroxygon-4-en-3-one for the uterine cytosol receptor of progesterone are reported, and the origin of the high progestational activity of norgestrel and 11 beta-substituted progestins is discussed.     

Stasis before gallstone formation: Altered gallbladder compliance or cystic duct resistance?

Gallbladder stasis occurs before gallstone formation and provides the link between the hepatic secretion of supersaturated bile and cholesterol cholelithiasis. We recently observed that cystic duct resistance increases while sphincter of Oddi resistance is unchanged in the presence of lithogenic bile without gallstones. Whether alterations in gallbladder function also lead to gallbladder stasis has been unclear. Therefore, we tested the hypothesis that before gallstone formation, stasis results from increased cystic duct resistance and altered gallbladder compliance. Adult, male prairie dogs were fed either a trace cholesterol (control) or a 0.4 percent cholesterol-enriched diet. Cystic duct resistance increased but gallbladder compliance was unchanged before gallstone formation. A significant correlation (p < 0.001) was found between the lithogenic index and cystic duct resistance in pregallstone animals. We conclude that increased resistance to flow across the cystic duct, and not altered gallbladder compliance, is etiologically related to bile stasis, an important event in gallstone formation.     

Postoperative T-tube cholangiography. Is antibiotic coverage necessary.

One hundred patients undergoing postoperative cholangiography had blood cultures drawn prior to and 15 minutes and six hours after cholangiography. Bile cultures obtained prior to cholangiography grew organisms in 92 of 100 patients with E. coli, Klebsiella pneumoniae and enterococcus being the bacteria most frequently isolated. Anaerobes were isolated from the bile in 21% of the patients. Nine of 83 patients (11%) not receiving antibiotics developed a bacteremia after cholangiography with organisms identical to those in the bile. All nine patients recovered without further complications of cholangiography. Those who developed a bactermia could not be distinguished from the group as a whole on the basis of age, sex, laboratory data, type of surgery or cholangiographic findings. None of the eight patients with negative bile cultures and none of 17 patients on antibiotics at the time of cholangiography experienced a bacteremia. Ninety to 93% of 304 organisms isolated from the bile were sensitive to a combination of a penicillin and an aminoglycoside. Most patients undergoing postoperative tube cholangiography do not develop a bacteremia and do not require antibiotics. Only patients with positive bile cultures who might tolerate a bacteremia poorly, and those who are febrile from cholangitis immediately prior to cholangiography should be covered with a short course of systemic antibiotics.     

Thallium-201: non-invasive determination of the regional distribution of cardiac output

Sapirstein (1) employed cationic radiopotassium to determine the fractional distribution of cardiac output to several organs. Thallium-201 can substitute for radiopotassium in myocardial imaging, and was evaluated in the present studies to determine the distribution of cardiac output in the anesthetized dog in comparison with tracer microspheres, both under control circumstances and following the infusion of norepinephrine in a dose sufficient to raise the blood pressure 20 mm Hg above control levels. The concentrations of thallium-201 and microspheres were similar in the heart, kidney, thyroid, and skeletal muscle in both control and norepinephrine-treated animals (r=0.93). Thallium concentration in the liver and lung exceeded that of microspheres, however, and probably is not related solely to the regional distribution of arterial perfusion. These data suggest that in the heart, kidney, thyroid, and skeletal muscle, thallium-201 distribution reflects the fractional distribution of cardiac output.