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Estrogen receptor (ER) determination in human mammary tumors was performed by enzyme immunoassay (EIA) using monoclonal antibody, and the results were compared with those obtained using the dextran-coated charcoal (DCC) and sucrose density gradient (SDG) method. Twenty ER-positive tumors by the DCC method were all ER-positive by EIA, when determined in the same cytosol fraction. Three out of 21 ER-negative tumors by the DCC method were ER-positive by EIA. Estrogen receptors of 8S, 8S + 4S, and 4S determined by the SDG method were all shown to be ER-positive using EIA. Between the values of estrogen receptors determined by the DCC method and by EIA, a high correlation was observed (r = 0.868). Values of ER less than 13.5 fmol/mg protein were considered as negative ER.

A series of functionalized congeners of 1,3-dialkylxanthines has been prepared as adenosine receptor antagonists. On the basis of the high potency of 8-(p-hydroxyphenyl)-1,3-dialkylxanthines, the parent compounds were 8-[4-[(carboxymethyl)oxy]phenyl] derivatives of theophylline and 1,3-dipropylxanthine. A series of analogues including esters of ethanol and N-hydroxysuccinimide, amides, a hydrazide, an acylurea, and anilides were prepared. The potency in blocking A1-adenosine receptors (inhibition of binding of N6-[3H]cyclohexyladenosine to brain membranes) and A2-adenosine receptors (inhibition of 2-chloroadenosine-elicited accumulations of cyclic AMP in brain slices) was markedly affected by structural changes distal to the primary pharmacophore (8-phenyl-1,3-dialkylxanthine). Potencies in the dipropyl series at the A1 receptor ranged from Ki values of 1.2 nM for a congener with a terminal amidoethyleneamine moiety to a Ki value of 58 nM for the parent carboxylic acid to a Ki of 96 nM for the bulky ureido congener. Certain congeners were up to 145-fold more active at A1 receptors than at A2 receptors. Various derivatives of the congeners should be useful as receptor probes and for radioiodination, avidin binding, and preparation of affinity columns.

The blood coagulation system of 66 consecutive patients undergoing consecutive liver transplantations was monitored by thrombelastograph and analytic coagulation profile. A poor preoperative coagulation state, decrease in levels of coagulation factors, progressive fibrinolysis, and whole blood clot lysis were observed during the preanhepatic and anhepatic stages of surgery. A further general decrease in coagulation factors and platelets, activation of fibrinolysis, and abrupt decrease in levels of factors V and VIII occurred before and with reperfusion of the homograft. Recovery of blood coagulability began 30-60 min after reperfusion of the graft liver, and coagulability had returned toward baseline values 2 hr after reperfusion. A positive correlation was shown between the variables of thrombelastography and those of the coagulation profile. Thrombelastography was shown to be a reliable and rapid monitoring system. Its use was associated with a 33% reduction of blood and fluid infusion volume, whereas blood coagulability was maintained without an increase in the number of blood product donors.

A ureolytic strain of Proteus mirabilis, isolated from a patient with infectious kidney stones, produced struvite (MgNH4PO4 X 6 H2O) and apatite [Ca10(PO4)6CO3] crystals in vitro when grown in artificial urine. Surface-attached crystals were encased in a slime-like layer. Scanning electron microscopy revealed that surfaces submerged in the artificial urine were colonized by P. mirabilis. Bacteria-associated crystals appeared soon after colonization and eventually became coated with an amorphous substance. Energy-dispersive X-ray analysis of these crystals revealed the presence of Mg, Ca, and P which are major components of struvite and apatite. Transmission electron microscopy of surface scrapings revealed that the glycocalyx of P. mirabilis contained a large number of crystals. Based on these observations and previous work, a theory for infectious renal calculogenesis is proposed. The kidney is initially colonized by invading ureolytic pathogens. These pathogens secrete copious amounts of glycocalyx which facilitates adhesion of the organisms to the kidney, provides protection for these bacteria, and serves to bind struvite and apatite crystals that result from bacterial urease activity. Growth of these calcified microcolonies into mature stones is characterized by continued bacterial growth, incorporation of urinary mucoproteins into the matrix along with bacterial glycocalyx, and a continued deposition of struvite and apatite crystals due to the high pH. The mature stone, in effect, represents an enlarged "fossilized" bacterial microcolony.

The 2-mum circle DNA of yeast encodes a site-specific recombination system (FLP recombination). The recombination region had been mapped earlier to a 65-base-pair (bp) segment within the 599-bp-long inverted repeats of the molecule. I have shown that the "minimal" FLP substrate resides in a 13-bp dyad symmetry plus an 8-bp core located within the 65-bp recombination region. Further, as determined by different in vivo assays, sequences extraneous to the minimal FLP site and the 65-bp recombination region can affect the efficiency of the recombination reaction.

Emphasis was put on the comparative quantitative structure-activity approaches to the exploration of action mechanisms of structurally different classes of compounds showing the same type of activity as well as those of the same type of compounds having different actions. Examples were selected from studies performed on insecticides and plant growth regulators, i.e., neurotoxic carbamates, phosphates, pyrethroids and DDT analogs, insect juvenile hormone mimics, and cytokinin agonistic and antagonistic compounds. Similarities and dissimilarities in structures required to elicit activity between compounds classes were revealed in terms of physicochemical parameters, provoking further exploration and evoking insights into the molecular mechanisms of action which may lead to the development of new structures having better qualities.

When washed cells of Mycoplasma gallisepticum were incubated at 37 degrees C in 250 mM 22NaCl, the intracellular Na+ increased, and the K+ decreased. The addition of glucose to these Na+-loaded cells caused Na+ efflux and K+ uptake (both ions moving against concentration gradients). This effect of glucose was blocked by the ATPase inhibitor dicyclohexylcarbodiimide, which prevents the generation of a proton motive force in these cells. In additional experiments, Na+ extrusion was studied by diluting the 22Na+-loaded cells into Na+-free media and following the loss of 22Na+ from the cells. Glucose stimulated 22Na+ extrusion in such cells by a dicyclohexylcarbodiimide-sensitive mechanism. Proton movement was studied by measuring the pH gradient across the cell membrane with the 9-aminoacridine fluorescence technique. Glucose addition to cells preincubated with cations other than Na+ resulted in cell alkalinization (which was prevented by dicyclohexylcarbodiimide). This observation is consistent with the operation of a proton-extruding ATPase. When glucose was added to Na+-loaded cells and diluted into Na+-free media, intracellular acidification was observed, followed several minutes later by a dicyclohexylcarbodiimide-sensitive alkalinization process. The initial acidification was probably due to the operation of an Na+-H+ antiport, since Na+ exit was occurring simultaneously with H+ entry. When Na+-loaded cells were diluted into Na+-containing media, the subsequent addition of glucose resulted in a weak acidification, presumably due to H+ entry in exchange for Na+ (driven by the ATPase) plus a continuous passive influx of Na+. All of the data presented are consistent with the combined operation of an ATP-driven proton pump and an Na+ -H+ exchange reaction.

Hypercoagulation caused by decreased antithrombin III level leads to thrombosis inspite of postoperative prophylactic heparin therapy. Induced low level of antithrombin III is recognised in particular diseases which lead to a reduced ATIII synthesis, high breakdown or loss. Induced forms should be substituted with ATIII transfusions. Congenital forms should be treated lifelong with coumarin derivates. One should always suspect an ATIII deficiency when in spite of full heparin dosage a prolonged plasma thrombin time is not attained. A case history of recurrent thrombosis may also point to such deficiency.

Estrogen receptor (ER) was measured in 275 samples from 170 patients with breast cancer by DCC assay. The results showed that the ER status and content of cytosol separated by ultracentrifuge (105,000 X G) or orthocentrifuge (1,200 X G) confirmed well (P greater than 0.5). Therefore, the ordinary centrifuge is suitable. But there was a poor correlation between the ER level measured by DCC method and that by Lee's cytochemical method (P greater than 0.05). The store time of the sample in liquid nitrogen did not seem to effect much on the ER positive rate (chi 2 = 0.7686). The ER status in samples obtained from the primary or metastatic lesion or at different intervals were generally similar in the same patient (P greater than 0.2). It is suggested that the ER status be an inherent property of patients with breast cancer. The authors propose that more samples be taken in order to render the determination more reliable.