[Experience with virtual sonography of the breast].

OBJECTIVE: To assess the capabilities of and the first experience with an ACUSON S2000 automated breast volume scanner (ABVS) (Siemens, Germany) to detect abnormal breast lumps. MATERIAL AND METHODS: Examinations were made in 97 patients who underwent radiological studies encompassing digital mammography, B-mode ultrasonography of the breast, and its pathomorphological examination. All the cases were classified according to the BI-RADS system. Abnormal breast lumps (BI-RADS 1) were not found in 27 cases; clearly defined benign masses (BI-RADS 2) were detected in 18, and pathomorphologically verified breast cancer (BC) (BI-RADS 5) in 29 cases. All the patients also underwent breast ultrasonography using an ACUSON S2000 system (Siemens, Germany). The results of ABVS examination were compared with those of standard comprehensive breast radiologic examination. Having no preliminary additional information on each patient, an independent expert--a radiologic diagnostician appraised all ultrasound scanning data at a special review station. RESULTS: The sensitivity of the automated scanning assay in detecting breast abnormalities was 100%; its specificity and diagnostic accuracy were 40 and 88%, respectively. The independent expert established the diagnosis of BC in 26 (90%) of the 29 cases. According to the results of automated breast scanning, pre-examination using a set of radiation methods was recommended in 66 (66%) cases. The hyperdiagnosis was 24%. CONCLUSION: Taking into consideration the fact that none of the BC case was overlooked, the first experience with ABVS showed encouraging results and the need for further clinical tests of the automated breast scanning system.

Cytokeratin 19 mRNA concentration in lymph nodes as a diagnostic marker of metastases.

Comparison of the sensitivity of cytological and molecular genetic methods (19 specimens of lymph nodes from 8 patients with breast cancer and suspected metastases obtained by transcutaneous fine-needle aspiration biopsy under ultrasound guidance) showed that molecular genetic and cytological studies produced true results in 95 and 84% specimens, respectively. True-positive and true-negative results were obtained in 8 and 7 patients, respectively. Expression of cytokeratin 19 was detected in 3 specimens with negative cytological results and confirmed metastases in lymph nodes. Our results indicate that molecular genetic diagnostic study for lymph node metastases should be used in small amounts of biopsy specimens, presence of marginal metastases in lymph nodes, and negative results of repeated cytological examination.

[Evaluation of axillary lymph nodes from the results of radioisotopic study].

The purpose of the investigation was to study the pattern of 99mTc (MIBI) technitrile uptake in the metastatically involved lymph nodes in breast cancer, by applying the plain scintigraphic technique. The scintigraphic study of the breast and regional metastatic areas by means of the radionuclide 99mTc (MIBI) technitrile was made on a Millennium GE tomographic gamma chamber. The radiotracer 550 (MBq) dissolved in 10-20 ml of saline solution was intravenously injected into the arm cubital vein contralaterally to the lesion. Following 20 minutes of injection of the agent, plain scintigraphy was carried out in three standard projections: frontal and two oblique ones. The scintigraphy was performed using a high-resolution collimator recording a 128 x 128 matrix image. The detector was maximally approximated to the organ being examined. A plain scintigraphic scan was recorded on each side for 10 minutes. By the degree of axillary lymph nodal involvement, the patients were divided into 3 groups in accordance with the international TNM classification: N0 (n = 55), N1 (n = 13), N2 (n = 4). Among 72 patients, axillary lymph nodes could be detected in 6, in 2 of them changes were not diagnosed by X-ray and ultrasound studies. The final pathomorphological study of intraoperative materials revealed axillary lymph nodal metastatic involvement in 17 patients. A micrometastasis in one lymph node was found in 1 patient. None of the radionuclide studies showed tumor spread in 5 cases. The sensitivity, specificity, and precision of the technique were 35.3, 100, and 84.7%, respectively. Thus, a combination of the high cost of the procedure, its radiation load on a patient, and its low sensitivity make the use of plain scintigraphy of axillary regions inexpedient in the complex of studies of the extent of breast cancer in the present development of technology.

Structural changes of hake (Merluccius merluccius L.) fillets: effects of freezing and frozen storage.

Structural changes in hake (Merluccius merluccius L.) fillets as affected by freezing method and frozen storage temperature have been studied through Raman spectroscopy and related to changes in texture and functionality. Changes in protein secondary structure were observed due to storage temperature, accompanied by changes in apparent viscosity and shear resistance. Samples at -10 degrees C showed greater structural alteration than at -30 degrees C in terms of increase of beta-sheets at the expense of alpha-helices. An increase of unordered protein structure was found only in samples stored at -10 degrees C. Exposure of buried tryptophan residues was observed at both storage temperatures. The decrease of the deltaCH(2) band upon storage suggested an increase of hydrophobic interactions of aliphatic residues. Except for liquid air frozen fillets, all samples showed a decrease of the nuO-H/nuC-H band ratio compared to the fresh ones, this decrease being higher the harsher the conditions.

Characteristics of the salt-soluble fraction of hake (Merluccius merluccius) fillets stored at -20 and -30 degrees C.

Natural actomyosin (NAM) extracted in 0.6 M NaCl from hake fillets stored at -20 and -30 degrees C for up to 49 weeks was studied. The extracted protein decreased as storage progressed and became poorer in myosin while the proportion of actin remained constant. Two major peaks composed of myosin plus actin and actin plus tropomyosin plus troponins were obtained by size exclusion chromatography. SDS-PAGE analysis of the protein retained in the precolumn filter showed that there was protein aggregated by covalent bonding. Surface hydrophobicity increased while Ca(2+)-ATPase activity, apparent viscosity, and SH groups decreased as storage progressed. The loss of Ca(2+)-ATPase activity was due mainly to denaturation of the extracted myosin, whereas the minimum viscosity values occurred earlier and were not directly due to the lower proportion of myosin in the extracts. Thus, the extracted NAM exhibited changes during frozen storage. The temperature-dependent difference was mainly quantitative due to a smaller amount of protein extracted at -20 degrees C.