Doppler sonography in experimentally induced acute renal failure in rabbits. Resistive index versus serum creatinine levels

RATIONALE AND OBJECTIVES

The purpose of this study is to investigate the temporal relation between the change in the resistive index (RI) from renal Doppler sonography and that of serum creatinine values in the course of experimentally induced reversible acute renal failure (ARF) in rabbits.

METHODS

Reversible ARF was induced in 10 New Zealand white rabbits by injecting a glycerol solution (6.0 mL/kg) into the thigh muscle. Doppler sonography was performed before injection, and 6, 12, and 24 hours, and 3, 5, 7, and 14 days after injection of glycerol. Blood samples for measuring serum creatinine levels were obtained in the same time sequence. Three rabbits, which died during the course of the experiment, were excluded from the study group.

RESULTS

The RI elevated rapidly after glycerol injection, peaked at 12 hours, and then decreased to normal values by 7 days. Conversely, serum creatinine values were elevated and peaked at 1 day and then decreased to normal by 14 days. The change in the RI preceded the change in serum creatinine levels in the course of reversible ARF. There was a weak linear correlation between RI and serum creatinine levels, with a correlation coefficient of 0.33.

CONCLUSION

Doppler sonography with measurement of resistive index may be useful in predicting the course of ARF.

Iatrogenic dissection of the celiac artery and its branches during transcatheter arterial embolization for hepatocellular carcinoma: outcome in 40 patients

PURPOSE

To study the sequelae of iatrogenic dissection of the celiac axis and its branches in a large patient population.

METHODS

We analyzed 40 patients with hepatocellular carcinoma (HCC) whose celiac artery or its branches were dissected during transcatheter arterial embolization (TAE) and underwent follow-up angiography within 2 months.

RESULTS

The two most common sites of dissection were the celiac artery in 13 patients (32.5%) and the proper hepatic artery in 11 patients (27.5%). Follow-up angiography revealed complete recanalization in 32.5% (13/40), irregularity and narrowing of the lumen in 40% (16/40), and complete obstruction in 27.5% (11/40). Therefore, 72.5% (29/40) of the dissected arteries recanalized. Pseudoaneurysm formation of the dissected artery was observed in 32.5% (13/40). Subsequent TAE was possible via the dissected arteries in 79% (27/34) of patients in this series.

CONCLUSION

Iatrogenic dissection of the celiac and proximal hepatic arteries heals spontaneously in the majority of patients, and in most instances allows subsequent TAE.

MR findings of secondary hemochromatosis: transfusional vs erythropoietic

OBJECTIVE

The aim of this study was to demonstrate the MR characteristics of secondary hemochromatosis (transfusional versus erythropoietic).

MATERIALS AND METHODS

Magnetic resonance images of five patients with transfusional (n = 3) or erythropoietic (n = 2) hemochromatosis were reviewed.

RESULTS

The liver of all patients had low signal intensity in all pulse sequences. The spleen had low signal intensity in all patients with transfusional iron overload, but normal signal intensity in erythropoietic hemochromatosis, which had similar MR findings to idiopathic hemochromatosis. However, the pancreas had variable signal intensity.

CONCLUSION

On MRI the signal intensity of the spleen may allow distinction between transfusional and erythropoietic hemochromatosis.

Influence of the conjugation site on the specificity of monoclonal antibodies to progesterone and on the performance of direct enzyme immunoassay

Monoclonal antibodies against progesterone conjugated to carrier protein through substituent on the A-ring (C3 position ) or the C-ring (C11 position) of progesterone were used in the enzyme immunoassay. Antibody specificities were determined by testing the ability of 11 represensitive steroids to displace labelled progesterone in a competitive enzyme immuno-assay (EIA) and a radioimmunoassay (RIA). Immunization with progesterone conjugated to BSA through substituent on the A-ring (C3) resulted in the formation of monoclonal antibody (mAb) which fairly specific for progesterone. While immunization with progesterone at the 11-position (C11) resulted in the mAbs which were very specific for progesterone. The best EIA system was developed by using mAb against progesterone-11 alpha -hemisuccinyl BSA and tracer of progesterone-3(O-carboxymethyl oxmine)-horseradish peroxidase. Our approach is to confirm the overall orientation of the steroid in the binding site. Immunobiochemical analysis of mAb suggested that the D-ring is substantially more buried in the binding pocket than the A-ring. Our assay was designed to use the reagent inactivating cholesterol binding globulin in serum so that the extraction of the hormone into organic solvent was unnecessary. Therefore, our assay system can detect directly and rapidly the progesterone level in serum within one hour.

Retrieval of intravascular foreign bodies with the snare and catheter capture technique

The authors report two cases of retrieval of iatrogenically placed intravascular metallic foreign bodies: a guide wire in the abdominal aorta and a guide-wire fragment in the inferior vena cava. The foreign bodies were retrieved with use of a new approach described as the "snare and catheter capture technique." This technique is useful with guide wires that are too stiff to safely remove doubled over.

Solid-phase immunoassay using a flow cytometer: quantitative and qualitative determination of protein antigens and a hapten

A fluoroimmunoassay employing a flow cytometer as the fluorescence-detecting device is described. Three kinds of antigens, murine immunoglobulin (Ig), human chorionic gonadotropin (hCG) and progesterone were chosen as examples of the assay using fluorescein-labeled antibodies. Cyanogen bromide-activated agarose beads were used as solid-phase supporters. The flow cytometric immunoassay was applied to both qualitative and quantitative analyses; determination of murine Ig isotypes, quantitative determination of Ig, hCG and a hapten, progesterone. This assay produced very reproducible and less-fluctuating data since thousands of particles in the assay were collected and processed to produce a single value for fluorescence intensities. Furthermore, the working range of the assay in terms of antigen concentration was much broader than that of enzyme immunoassay. Therefore, we believe that microparticles like agarose beads could be useful solid-phase supporters in immunoassay, and the flow cytometer could provide a reliable alternative to the fluorescence-detecting device in immunoassay.