The effect of ultrasound with acoustic radiation force on rabbit lung tissue: a preliminary study

Purpose

Acoustic radiation force (ARF) elastography has recently become available. The previous animal studies have revealed lung injuries induced by diagnostic ultrasound, but the effects on the lung resulting from exposure to ultrasound with ARF are unknown. This study aimed to assess the risk of lung injury associated with ultrasound with ARF.

Methods

A focused 2.5-MHz transducer that emits ultrasound with ARF was used. A rabbit was anesthetized, and the transducer was placed in the right subcostal region. Exposure settings of mechanical index (MI) 0.80, pulse duration 10 ms, pulse repetition time 5 s, and exposure time 150 s were applied.

Results

One red spot (7 × 6 mm) was observed on the surface of the right lung corresponding to the area of exposure. Alveolar hemorrhage was observed microscopically. This lesion was visible across a range of 20–170 μm in depth from the pleural surface.

Conclusion

The first example of lung hemorrhage induced by ultrasound with ARF was observed in this study. This observation suggests the possibility of lung injury in humans when ARF elastography is applied with the transducer directed toward the lung. Further studies are needed to determine the safety of this modality.

     

Diagnostic values of gallbladder hyperperfusion and the rim sign in radionuclide angiography and hepatobiliary imaging

The diagnostic values of hyperperfusion to the gallbladder fossa and the rim sign were retrospectively evaluated in 24 histopathologically proven cases of gallbladder disease. Although 12 of 13 patients (92%) with acute cholecystitis had nonvisualization of the gallbladder, the positive predictive value with this finding was 71%. However, when the finding was associated with hyperperfusion to the gallbladder fossa or the rim sign, the positive predictive value with both (90%) was markedly increased compared to the prevalence ratio of 54%. Such a combination could be useful for preserving a high positive predictive value in the diagnosis of acute cholecystitis.     

Differential expression of CD45RO (UCHL1) and its functional relevance in two subpopulations of circulating TCR-gamma/delta+ lymphocytes

We examined the developmental profile of TCR-gamma/delta+ cells with respect to CD45RO expression. Although total TCR-gamma/delta+ cells were negligible in the neonatal blood and increased with advancing age, most blood TCR-gamma/delta+ cells markedly expressed CD45RO without a distinction of age, probably reflecting a different CD45RO expression of two subsets defined by BB3 and delta TCS1 mAbs. The vast majority of BB3+ cells expressed CD45RO, whereas expression of CD45RO was virtually absent in the delta TCS1+ population. Functional studies revealed that, while both TCR-gamma/delta+ cell subsets showed CD3-mediated activation, only BB3+ (or Ti gamma A+) cells, but not delta TCS1+ cells, appeared to proliferate in response to PPD in PPD-reactive individuals. The results suggested that the CD45RO+ (BB3+ or Ti gamma A+) subset among blood TCR-gamma/delta+ cells may be mainly involved in the memory or primed component of the immune system responding to some foreign antigens.     

Determination of branched-chain amino acids and tyrosine in serum of patients with various hepatic diseases, and its clinical usefulness

We developed an automated enzymatic method for determination of the branched-chain amino acids (BCAAs; valine, isoleucine, leucine) and tyrosine in serum, and applied it to the clinical evaluation of patients with various hepatic diseases. Analytically, the test results were acceptably precise and reproducible, and correlated well with results obtained with an amino acid analyzer. Clinically, we found that a decrease in BCAAs, an increase in tyrosine, and the BCAAs/tyrosine ratio in serum paralleled the severity of hepatic parenchymal damage. We conclude that this enzymatic determination of BCAAs and tyrosine is simple and convenient enough for routine clinical laboratory use, and that the ratio of BCAAs/tyrosine obtained may be a good indicator of the severity of hepatic disorders.     

ST segment and T wave alternans in a patient with Brugada syndrome

We describe a patient with Brugada syndrome in whom J point and ST-segment elevation in leads V1 and V2 were augmented by atrial pacing and intravenous administration of propranolol or cibenzoline. Significant T wave alternans with a 2:1 appearance of terminal negative T wave was observed in the absence and presence of atrial pacing after the administration of cibenzoline. The cellular mechanism responsible for T wave alternans, beat-to-beat appearance of terminal negative T wave and augmented J point and ST-segment elevation is discussed.     

Lysosomal acid hydrolases in lymphocytes of I-cell disease.

Several lysosomal acid hydrolases were assayed in peripheral blood leukocytes from a patient with I-cell disease by the method of Hindman, J. and Cotlier, E. ((1972) Clin. Chem. 18, 971--975). The activities of lysosomal hydrolases in polymorphonuclear cells showed no significant differences between the patient, the parents, and normal controls, while lymphocytes from the patient exhibited the reduced activities of alpha- and beta-galactosidases, beta-glucuronidase, and N-acetyl-beta-glucosaminidase. After phytohemagglutinin-stimulated culture, lymphocytes from the patient showed a more definite reduction in the activities of these lysosomal enzymes; the activities of beta-glucuronidase, alpha-mannosidase, and N-acetyl-beta-glucosaminidase were reduced to about 20--30% of the activity in the phytohemagglutinin-stimulated control cultures, and the activities of alpha- and beta-galactosidases to 10% or less. Lymphocytes from the parents showed no significant difference in the activities of these enzymes from the controls, whether stimulated or not.