The role of embolization in reducing the complications of cryoablation in renal cell carcinoma.

AIM: To investigate whether embolization prior to cryoablation would decrease morbidity without negative effects on tissue pathology, renal function, or recurrence. MATERIAL AND METHODS: The electronic medical records of all patients undergoing cryoablation for renal cell carcinomas were reviewed for lesion size, pre-ablative renal function, post-ablative renal function, post-ablative complications, recurrence, and quality of biopsy specimen. Comparisons were made between patients who underwent cryoablation (the Cryo-Only group) and those who underwent cryoablation after same-day coil embolization of their lesion (the Cryo-Embo group). Further comparison was made between the Cryo-Embo lesions and the subset of larger Cryo-Only lesions (≥ 3 cm), which were expected to have a higher natural complication rate. RESULTS: A total of 21 lesions in 19 patients were treated by percutaneous cryoablation (17 Cryo-Only, four Cryo-Embo). Complications were seen in 83% of the large Cryo-Only lesions (average size 3.6 cm), whereas no complication was seen amongst Cryo-Embo lesions (average size 4 cm). Embolization significantly decreased complications between size-matched lesions (p = 0.048) without impacting renal function (p = 1), biopsy quality (p = 1), or recurrence (p = 1). CONCLUSION: Performance of trans-arterial embolization prior to cryoablation of large renal cell carcinomas significantly decreases complications, such as haemorrhage, without a discernible effect on biopsy quality, renal function, or recurrence rate.

European earwig (Forficula auricularia) as a novel host for the entomopathogenic nematode Steinernema carpocapsae.

The natural history of many entomopathogenic nematode species remains unknown, despite their wide commercial availability as biological control agents. The ambushing entomopathogenic nematode, Steinernema carpocapsae, and the introduced European earwig, Forficula auricularia, forage on the soil surface. Since they likely encounter one another in nature, we hypothesized that earwigs are susceptible to nematode infection. In the laboratory, the LC(50) for F. auricularia was 226 S. carpocapsae/earwig and the reproductive potential was 123.5 infective juvenile nematodes/mg tissue. This susceptibility depended on host body size with significantly higher mortality rates seen in larger earwigs. In a study of host recognition behavior, S. carpocapsae infective juveniles responded to earwig cuticle as strongly as they did to Galleria mellonella cuticle. We also found that earwigs exposed to S. carpocapsae cleaned and scratched their front, middle and back legs significantly more than controls. Coupled with previous field data, these findings lead us to suggest that F. auricularia may be a potential host for S. carpocapsae.

Transjugular intrahepatic portosystemic shunt: efficacy for the treatment of portal hypertension and impact on liver transplantation.

Variceal bleeding (VB) and ascites refractory to diuretics (RA) represent a significant cause of morbidity and mortality in patients with portal hypertension. Transjugular intrahepatic portosystemic shunts (TIPS) have been used effectively in patients with these complications, especially those individuals awaiting orthotopic liver transplantation (OLT). From April 1992 to July 1995, 41 adult patients underwent an attempt at TIPS placement for refractory VB or ascites at Cedars-Sinai Medical Center. Technical success was achieved in 37 of 41 cases (90.3%) with only two technical complications. Immediate control of hemorrhage and significant improvement of ascites was obtained in 91.9% and 83.5% of the patients, respectively. Six patients (16.2%) died within a week of TIPS placement due to uncontrollable ascites and multiorgan failure. Four of 31 patients (12.9%) developed mild to moderate grades of hepatic encephalopathy that was controlled with lactulose. Rebleeding from recurrent portal hypertension was noted in 5 of 31 cases (16.1%). Shunt stenosis or occlusion was seen in 7 of 31 cases (22.6%) at an average of 6.3 months following TIPS placement. Six patients underwent OLT within an average of 87 days after TIPS. These results indicate that TIPS appears to be an effective method for treatment of refractory VB and RA, especially for patients who are poor candidates for a surgical shunt or awaiting OLT. However, TIPS may not be considered a definitive solution for all patients with portal hypertension because of its current rate of shunt occlusion or stenosis.

Detection of main renal artery stenosis using phase-contrast cine MR angiography.

OBJECTIVE: The purpose of our study was to assess the ability of phase-contrast cine MR angiography to detect the presence of main renal artery stenosis. SUBJECTS AND METHODS: We prospectively evaluated 75 hypertensive patients form main renal artery stenosis using phase-contrast cine MR angiography. Each main renal artery was evaluated as normal or abnormal. Thirty-seven of the 75 patients underwent conventional arteriography or intraarterial digital subtraction arteriography; these results were compared with the MR angiographic interpretations. Only those patients who had confirmatory arteriography were included in the statistical analysis. RESULTS: Thirty-six main renal arteries interpreted as normal by MR angiography were found to be without a focal stenosis on invasive arteriography. MR angiography suggested 32 main renal artery stenoses; invasive arteriography showed 29 of these as stenoses. Three main renal arteries that were interpreted as having focal stenoses by MR angiography were shown to be not stenotic by invasive arteriography. Three other patients had diffusely narrowed main renal arteries bilaterally without a focal stenosis on MR angiography; bilateral proximal renal artery stenoses were seen at arteriography in two of these patients, and diffusely narrowed main renal arteries were seen in the third patient. Thus, the sensitivity of phase-contrast cine MR angiography for detecting a focal stenosis or abnormal main renal artery was 100% (95% confidence interval, 88-100%) and the specificity was 93% (95% confidence interval, 80-99%). The kappa coefficient was 0.85 with a standard error of 0.08. CONCLUSION: Phase-contrast cine MR angiography had a high degree of accuracy and a high negative predictive value in detecting the presence of main renal artery stenoses and may be a good screening technique for renovascular hypertension.

Neonatal VH, D, and JH gene usage in rabbit B lineage cells.

The neonatal antibody repertoire in both mouse and humans differs from that of the adult repertoire in that the neonatal repertoire uses a limited set of JH-proximal VH genes but the adult repertoires use many different VH genes. Rabbits are unusual in that adults use only three or four VH genes, with approximately 80% of the B cells using VH1, the 3'-most VH gene. To investigate whether the repertoire of neonatal rabbits differs from that of adults, we analyzed VH, D, and JH gene usage in B cells of neonatal rabbits. A total of 68 rearranged VDJ genes was cloned from mRNA and genomic DNA isolated from lymphoid tissues of newborn to 10-day-old rabbits. We found that 74% of the VDJ gene rearrangements utilized VH1 and 15% utilized the genes that we designated VHx or VHy. From the remaining VDJ genes we identified seven novel VH genes, one, VHz, which was found in mRNA. We conclude that the repertoire of utilized VH genes in neonates is limited and is similar to that of adult rabbits. We also found the D1, D2a, D2b, and JH4 gene segments preferentially rearranged. We suggest that the preferential usage of VH, D, and JH gene segments in VDJ genes is caused by preferential rearrangement rather than by selective expansion of B cells that utilize the gene segments.

Induction of human monocyte IL-1 mRNA and secretion during anti-CD3 mitogenesis requires two distinct T cell-derived signals.

The T cell signals that regulate the induction of human monocyte IL-1 during primary immune activation were investigated by using anti-CD3 mitogenesis. The induction of monocyte IL-1 alpha and beta mRNA during anti-CD3 mitogenesis was rapid (less than or equal to 1 h) and required the presence of both T cells and anti-CD3. The addition of T cells plus a nonmitogenic anti-CD5 antibody failed to induce IL-1 alpha or beta mRNA, indicating that IL-1 mRNA induction by anti-CD3 required T cell activation. Experiments using double chamber culture wells revealed that the major initial phase of IL-1 alpha and beta mRNA induction (1 to 12 h) required direct cell contact between monocytes and T cells. A subsequent minor late phase (greater than or equal to 12 h) of IL-1 mRNA was induced independently of cell contact in monocytes that received only soluble factors generated during anti-CD3 mitogenesis and was temporally associated with the appearance in culture supernatants of the late phase IL-1-inducing cytokines, IL-2, IFN-gamma, and TNF-alpha. Metabolic inactivation of T cells using paraformaldehyde demonstrated that the ability of T cells to induce IL-1 mRNA via cell contact was acquired only after activation of T cells via solid phase anti-CD3. Furthermore, pretreatment of T cells with the protein synthesis inhibitor emetine had no effect on T cell-mediated induction of monocyte IL-1 mRNA or cell-associated IL-1 alpha and beta, indicating that the expression of the IL-1 inductive signal did not require protein synthesis. Despite their ability to induce monocyte IL-1 alpha and beta mRNA, activated T cells treated with paraformaldehyde or emetine were no longer able to induce monocytes to secrete IL-1 beta into culture supernatants. However, supernatants from purified T cells that were activated with solid-phase anti-CD3 restored the ability of paraformaldehyde or emetine-treated T cells to induce IL-1 secretion. These studies provide evidence that supports a two-signal model of monocyte IL-1 production during primary immune activation. The first signal leads to the induction of monocyte IL-1 mRNA and is mediated by direct contact with activated T cells, and the second signal is provided by soluble T cell factors and results in IL-1 secretion.

Identification of monoclonal antibody binding domains of Na+,K(+)-ATPase by immunoelectron microscopy.

Treatment of purified preparations of porcine Na+,K(+)-ATPase with phospholipase A2, MgCl2 and NaVO3 leads to the formation of two-dimensional crystals exclusively in a dimeric configuration. Two-dimensional computer-averaged projections of the electron microscopy images of the crystalline enzyme with bound Fab fragments of monoclonal antibody M10-P5-C11 were accomplished using image enhancement software and showed that the antibody fragments caused only a modest increase in the unit cell size, while reducing the extent of asymmetry of the two promoters in each unit cell. The digital imaging also showed that the antibody's epitope on the alpha subunit resides on the 'lobe' or 'hook' region of the intracellular portion of the enzyme. Since functional studies indicate that M10-P5-C11 binds near or between the ATP binding site and the phosphorylation site, this visualized 'lobe' region of alpha may comprise the catalytic site. In addition, the binding of another inhibitory antibody, 9-A5, has been found to prevent crystal formation and the presence of the carbohydrate sugars on the enzyme's beta subunit shown to be required for crystal formation.

Proficiency in personal selling: prescription for physician marketing.

In a highly competitive and dynamic environment health care providers are turning to marketing techniques to compete. To date, the majority of marketing efforts in the health care industry have revolved around the use of promotional tools, mainly advertising, publicity and public relations. It is proposed here that personal selling is a neglected, but important, promotional tool for health care marketers, especially physicians. The analogy between physician and salesperson is drawn, various influence techniques commonly used in personal selling situations are discussed, and a methodology proposed for the systematic study of how physicians might adjust their use of such personal influence techniques to the situation so as to be more effective in terms of patient satisfaction and compliance.

Determination of monoclonal antibody-induced alterations in Na+/K+-ATPase conformations using fluorescein-labeled enzyme.

The fluorescein 5'-isothiocyanate (FITC)-labeled lamb kidney Na+/K+-ATPase has been used to investigate enzyme function and ligand-induced conformational changes. In these studies, we have determined the effects of two monoclonal antibodies, which inhibit Na+/K+-ATPase activity, on the conformational changes undergone by the FITC-labeled enzyme. Monitoring fluorescence intensity changes of FITC-labeled enzyme shows that antibody M10-P5-C11, which inhibits E1 approximately P intermediate formation (Ball, W.J. (1986) Biochemistry 25, 7155-7162), has little effect on the E1 in equilibrium E2 transitions induced by Na+, K+, Mg2+ Pi or Mg2+. ouabain. The M10-P5-C11 epitope, which appears to reside near the ATP-binding site, does not significantly participate in these ligand interactions. In contrast, we find that antibody 9-A5 (Schenk, D.B., Hubert, J.J. and Leffert, H.L. (1984) J. Biol. Chem. 259, 14941-14951) inhibits both the Na+/K+-ATPase and p-nitrophenylphosphatase activity. Its binding produces a 'Na+-like' enhancement in FITC fluorescence, reduces the ability of K+ to induce the E1 in equilibrium E2 transition and converts E2.K+ to an E1 conformation. Mg2+ binding to the enzyme alters both the conformation of this epitope region and its coupling of ligand interactions. In the presence of Mg2+, 9-A5 binding stabilizes an E1.Mg2+ conformation such that K+-, Pi- and ouabain-induced E1----E2 or E1----E2-Pi transitions are inhibited. Oubain and Pi added together overcome this stabilization. These studies indicate that the 9-A5 epitope participates in the E1 in equilibrium E2 conformational transitions, links Na+-K+ interactions and ouabain extracellular binding site effects to both the phosphorylation site and the FITC-binding region. Antibody-binding studies and direct demonstration of 9-A5 inhibition of enzyme phosphorylation by [32P]Pi confirm the results obtained from the fluorescence studies. Antibody 9-A5 has also proven useful in demonstrating the independence of Mg2+ ATP and Mg2+Pi regulation of ouabain binding. In addition, [3H]ouabain and antibody-binding studies demonstrate that FITC-labeling alters the enzyme's responses to Mg2+ as well as ATP regulation.

Sequestration electrochemistry: the interaction of chlorpromazine and human orosomucoid.

A simple and rapid method is presented for determination of the association constants and stoichiometries describing ligand macromolecule interactions. Based on flow injection analysis and electrochemical detection by amperometry, the only requirements for direct measurements are that the ligand have redox properties and that these properties change upon binding to the macromolecule. Bound ligand may then be measured in the presence of free ligand. Detection limits are of the order of 2 pmol of ligand or less, a level that should provide access to previously unmeasurable systems. For the exemplary system, chlorpromazine and human orosomucoid, K0ass was determined as 0.39 X 10(6) M-1 with 0.76 chlorpromazine binding sites of this affinity per orosomucoid molecule.

Immunochemical evidence that the FITC-labeling site on Na+,K+-ATPase is not the ATP binding site.

The covalent labeling of the alpha subunit of lamb kidney Na+,K+-ATPase by fluorescein 5'-isothiocyanate at Lys-501 has generally been assumed to occur at the ATP binding site. We have found that the peptide sequence 496HLLVMKGAPER506 serves as the antigenic determinant for monoclonal antibody M8-P1-A3. This antibody binds to both native and FITC-labeled enzyme and while this epitope undergoes ligand-induced changes these changes are not involved in either enzyme function or the E1 in equilibrium E2 conformational changes monitored by FITC-fluorescence intensity.

The influence of N-acetylneuraminic acid on the properties of human orosomucoid.

Little is known of the relationships that may exist among the three principal functionalities of glycoproteins. Orosomucoids of closely defined N-acetylneuraminic acid content were examined for evidence of influence of N-acetylneuraminic acid content on the physical properties of the glycoprotein. Fluorescence spectroscopy gave no indication of conformational change in the protein core upon desialylation. Small changes in the chromatographic partition coefficient, sigma, and thermal stability, Td, are interpreted to reflect loss of water of hydration and increased glycan stem-protein interaction without a major repositioning of the chains. Ligand-binding measurements indicate no alteration in the hydrophobic binding domain and a possible interaction between chlorpromazine and N-acetylneuraminic acid. All changes seen are progressive and occur through a region where changes in biological activity are not found. It is suggested that the dependence of biological activity on N-acetylneuraminic acid content in orosomucoid reflects, not coupled changes in protein conformation, but a charge-density-related interaction such that, below a contribution of four or five N-acetylneuraminic acid residues, activity is modified.

Fluorescence quenching of human orosomucoid. Accessibility to drugs and small quenching agents.

The fluorescence behaviour of human orosomucoid was investigated. The intrinsic fluorescence was more accessible to acrylamide than to the slightly larger succinimide, indicating limited accessibility to part of the tryptophan population. Although I- showed almost no quenching, that of Cs+ was enhanced, and suggested a region of negative charge proximal to an emitting tryptophan residue. Removal of more than 90% of sialic acid from the glycan chains led to no change in the Cs+, I-, succinimide or acrylamide quenching, indicating that the negatively charged region originates with the protein core. Quenching as a function of pH and temperature supported this view. The binding of chlorpromazine monitored by fluorescence quenching, in the presence and in the absence of the small quenching probes (above), led to a model of its binding domain on orosomucoid that includes two tryptophan residues relatively shielded from the bulk solvent, with the third tryptophan residue being on the periphery of the domain, or affected allotopically and near the negatively charged field.

Crystallization of alpha 1-acid glycoprotein.

Crystals of alpha 1-acid glycoprotein have been grown reproducibly from delipidated protein in the presence of chlorpromazine. The crystals are large hexagonal prisms of space group either P622 or P6(2)22 and the unit cell dimensions are a = b = 101 A and C = 201 A. The unit cell is very highly hydrated and is nearly 80% solvent. It contains one molecule of protein per asymmetric unit. The crystals diffract only to low resolution, presumably reflecting the extensive hydration and accompanying disorder.

The preparation of orosomucoid from nephrotic urine.

A gel chromatographic and ion exchange procedure is described for the preparation of orosomucoid from nephrotic urine. The removal of endogenous lipid and glycosaminoglycan than yields a highly homogeneous preparation. Aggregates are formed at ambient temperatures and as a result of lyophilisation of ultrafiltration.

Comparison of CT scanning and radionuclide imaging in liver disease.

Early experience with body CT suggested its usefulness in many diagnostic problems; jaundice, renal and pancreatic masses, and in the evaluation of relatively inaccessible parts of the body, such as the retroperitineum, mediastinum, and pelvis. Investigation of hepatic disease by CT was not unexpectedly compared to radionuclide liver scanning, the major preexisting modality for imaging the liver. In the evaluation of the jaundiced patient, CT rapidly assumed a major role, providing more specific information about the liver than the RN liver scan, as well as demonstrating adjacent organs. CT differentiate obstructive from non-obstructive jaundice, and frequently the cause of the obstructive jaundice. With respect to mass lesions of the liver, the RN liver scan is more sensitive than CT but less specific. The abnormalities on an isotope image of the liver consist of normal variants in configuration, extrinsic compression by adjacent structures, cysts, hemangiomata, abscesses, and neoplasms. These suspected lesions may then be better delineated by the CT image, and a more precise diagnosis made. The physiologic information provided by the RN liver scan is an added facet which is helpful in the patient with diffuse hepatic disease. The CT image will be normal in many of these patients, however, hemochromatosis and fatty infiltration lend themselves especially to density evaluation by CT. The evaluation of lymphoma is more thorough with CT. Structures other than the liver, such as lymph nodes, are visualized. Gallium, however, provides additional isotopic information in patients with lymphoma, and in addition, is known to be useful in the investigation of a febrile patient with an abscess. Newer isotopic agents expand hepatic imaging in other directions, visualizing the biliary tree and evaluating the jaundiced patient.

Reliability of gated heart scintigrams for detection of left-ventricular aneurysm: concise communication.

Gated heart scintigrams and angiocardiograms were performed on 138 patients with coronary artery disease. Scintigraphy detected 61 of 64 left-ventricular aneurysms demonstrated by angiography. The scintigram correctly identified all 54 apical and anteroapical aneurysms and one inferior aneurysm, but missed one of six anterior and two of three posterobasal aneurysms. In 74 patients with angiograms negative for aneurysm, the scintigram was also negative in 72, with two false positives. Overall accuracy of gated heart scintigraphy for the detection of aneurysm was 96% (133/138). Cardiac surgery was performed on 76 patients, and the angiographic findings were confirmed in all cases. Scintigraphic findings were confirmed in 74 of 76 patients. Among ten patients scintigraphed before and after aneurysmectomy, problems were first recognized by the scintigram in three cases. Gated heart scintigraphy is recommended as a screening procedure for suspected left-ventricular aneurysm because of its high reliability in the apical and anterior portions of the heart, where most of the aneurysms occur.