Percutaneous varicocele occlusion: long-term follow-up

We investigated the mechanism of resistance in murine L1210 leukaemia cells selected after treatment with FCE 23762 methoxymorpholinyl doxorubicin: (MMRDX), a methoxymorpholinyl derivative of doxorubicin active in vitro and in vivo on multidrug-resistant (mdr) cells, currently undergoing phase I clinical trials. The resistant subline obtained after repeated in vitro treatments, L1210/MMRDX, is resistant in vitro and in vivo to all tested methoxymorpholinyl derivatives and to cyanomorpholinyl doxorubicin, but shows resistance to morpholinyl derivatives only in vivo or following their activation with rat S9-liver fractions in vitro. L1210/MMRDX cells are sensitive to classic mdr- and altered topoisomerase (AT)-mdr-associated drugs. These cells do not appear to overexpress the mdr1 gene, nor do they exhibit impaired intracellular drug accumulation and efflux or altered levels of glutathione and glutathione S-transferase. The extent of DNA single-strand break formation and, after microsomal activation, of DNA interstrand cross-links after treatment with MMRDX was similar in the parent and the resistant subline. The mechanism of resistance in L1210/MMRDX cells remains to be identified but may prove a novel one, highly specific for this class of mdr-active anthracyclines.     

From the Cleavers to the Clintons: role choices and body orientation as reflected in magazine article content

The media have been heavily implicated as sources of overconcern with body focus, attractiveness, and thinness, primarily for women. Attendant negative consequences are widely assumed. Yet there appears to be a recent media trend to concern with physical health and fitness, rather than just appearance. This trend has not been empirically assessed. Further, previous research has not adequately explored the possibility that there may be an assortment of physical ideals represented in the media, which may vary according to the different audiences being targeted. The current study assessed magazine article content, examining gender differences, time trends, and magazine audience type. Four types of article content were examined: health, fitness, beauty, and weight loss, in an attempt to capture the major aspects of body focus. The numbers of articles containing such content were tallied, over a 12-year period, in a sample of magazines oriented to three distinct audiences: traditional, high fashion, and modern. Huge gender differences were obtained, with female-targeted magazines not surprisingly outstripping male-targeted ones for all content categories assessed. There were also clear differences in content between magazine types. Time-trend analyses indicated a decrease in emphasis on weight loss in women's magazines over the period studied, and a statistical trend for an increase in weight loss focus in men's magazines. We conclude that apparent trends toward healthier habits are not just thinness goals revisited.     

Interstitial cells of the medulla and the renin-angiotensin system in disorders of water-salt homeostasis

Electron microscopic studies of the intersticial cells of the renal medullar layer and the count of lipid granules in them were conducted in two experimental states accompanied by a reduction of the circulating blood volume--72 hours of water-free diet and intravenous administration of Lazyx that possesses a potent natriuretic and diuretic effect. The concentration of renin and angiotensin was determined in the plasma of the same animals, using the radioimmunoassay technique, and the juxtaglomerular apparatus of the kidneys was examined. The study has demonstrated that the reduction of the circulating blood volume is accompanied, on the one hand, by a significant elevation of the plasma concentration of renin and angiotensin, and, on the other hand, by a reduction of the number of lipid granules in the intersticial cells that is interpreted by the authors as an index of an increased synthesis of renal prostaglandins. It has been concluded that a close functional interrelashionship exists between the two hormonal systems of the kidneys that regulate the water-electrolyte homeostasis, i.e. the renin-angiotensin system and the prostaglandins system.     

Pharmacokinetics of lithium in human plasma and erythrocytes

The time course of lithium concentration in plasma and RBCs was measured in normal adult males following administration of single and multiple doses of lithium carbonate. From the single dose profiles, it was determined that lithium distribution between plasma and RBCs is not a simple partitioning phenomenon. The single dose time course measurements in both blood components were fit to a two compartment pharmacokinetic model in which the plasma was representative of the central compartment and the RBCs were representative of the tissue compartment. The importance of correction for trapped plasma volume in studies measuring lithium RBC kinetics was emphasized. In this study it was also demonstrated that one can accurately predict plasma and RBC lithium concentrations which are observed following multiple dosing, on the basis of single dose parameters obtained in the same subject.     

Structure-activity of sulfones and sulfonamides on dihydropteroate synthetase from Neisseria meingitidis

The molecular interaction of various sulfones and sulfonamides with partially purified dihydropteroate synthetase from Neisseria meningitidis M-166 has been examined. The mode of action of the sulfones was similar to that of the sulfonamides. Both groups of drugs were competitive inhibitors of dihydropteroate synthetase with respect to p-aminobenzoate in a partially purified enzyme preparation. 4,4'-Diaminodiphenylsulfone was three times more effective than sulfadiazine and nine times more effective than sulfanilamide as a competitive inhibitor of dihydropteroate synthetase. The inhibitory activity of 4-amino-4'-acetamidodiphenylsulfone and 4-amino-4'-formamidodiphenylsulfone in this system eliminated their prior conversion to 4,4'-diaminodiphenylsulfone as a requirement for activity.     

The formation of blood system tolerance in rats to the repeated action of a stressor stimulus

Repeated immobilisation induced a biphasic dynamic of the blood system stress sensitivity: first, an increased neutrophilia, lymphocytopenia, bone marrow granulocyte depletion and activation of the erythropoiesis; second, a restitution of mature granulocyte-monocyte cells number in the bone marrow and accumulation of neutrophils in the spleen.