VsN, a Reliability-index of Shear-wave Measurement in Sonoelastography, Is Useful for the Diagnosis of Thyroid Tumor Malignancy.

BACKGROUND/AIM: Shear wave measurement (SWM) is a new elastography modality that quantifies the shear wave velocity (Vs) and the percentage of the net effective shear wave velocity (VsN). This study examined whether these parameters could be used to differentiate between malignant and benign thyroid tumors. PATIENTS AND METHODS: The study of SWM enrolled 111 patients (133 nodules) who underwent thyroid surgery. Overall, 61 nodules were diagnosed as benign and 72 as malignant, of which 68 nodules were diagnosed as papillary thyroid carcinoma (PTC) and 4 as follicular thyroid carcinoma (FTC). RESULTS: A preoperative SWM revealed that Vs was significantly higher and VsN significantly lower in the PTC compared to the benign nodules. The VsN of FTC was significantly lower than that of follicular adenoma. Multivariate analysis revealed that VsN significantly correlated with nodule malignancy. CONCLUSION: SWM parameters, especially VsN, can potentially differentiate between benign and malignant thyroid nodules non-invasively.

Extracellular polysaccharides of Rhodococcus rhodochrous S-2 stimulate the degradation of aromatic components in crude oil by indigenous marine bacteria.

Rhodococcus rhodochrous S-2 produces extracellular polysaccharides (S-2 EPS) containing D-glucose, D-galactose, D-mannose, D-glucuronic acid, and lipids, which is important to the tolerance of this strain to an aromatic fraction of (AF) Arabian light crude oil (N. Iwabuchi, N. Sunairi, H. Anzai, M. Nakajima, and S. Harayama, Appl. Environ. Microbiol. 66:5073-5077, 2000). In the present study, we examined the effects of S-2 EPS on the growth of indigenous marine bacteria on AF. Indigenous bacteria did not grow significantly in seawater containing AF even when nitrogen, phosphorus, and iron nutrients were supplemented. The addition of S-2 EPS to seawater containing nutrients and AF resulted in the emulsification of AF, promotion of the growth of indigenous bacteria, and enhancement of the degradation of AF by the bacteria. PCR-denaturing gradient gel electrophoresis analyses show that addition of S-2 EPS to the seawater containing nutrients and AF changed the composition of the bacterial populations in the seawater and that bacteria closely related to the genus Cycloclasticus became the major population. These results suggest that Cycloclasticus was responsible for the degradation of hydrocarbons in AF. The effects of 15 synthetic surfactants on the degradation of AF by indigenous marine bacteria were also examined, but enhancement of the degradation of AF was not significant. S-2 EPS was hence the most effective of the surfactants tested in promoting the biodegradation of AF and may thus be an attractive agent to use in the bioremediation of oil-contaminated marine environments.