ΤND: A Thyroid Nodule Detection System for Analysis of Ultrasound Images and Videos

In this paper, we present a computer-aided-diagnosis (CAD) system prototype, named TND (Thyroid Nodule Detector), for the detection of nodular tissue in ultrasound (US) thyroid images and videos acquired during thyroid US examinations. The proposed system incorporates an original methodology that involves a novel algorithm for automatic definition of the boundaries of the thyroid gland, and a novel approach for the extraction of noise resilient image features effectively representing the textural and the echogenic properties of the thyroid tissue. Through extensive experimental evaluation on real thyroid US data, its accuracy in thyroid nodule detection has been estimated to exceed 95%. These results attest to the feasibility of the clinical application of TND, for the provision of a second more objective opinion to the radiologists by exploiting image evidences.     

Ιnflammatory or septic arthritis associated with mycoplasma pneumonia in children: Two case reports and review of the literature

Inflammatory or septic arthritis due to Mp is an extremely unusual manifestation in children, and the functional outcome of the joints is difficult to be predicted. Two cases with Mp infection are presented. The first patient had positive PCR for Mp after hip aspiration and arthrotomy with thorough irrigation and debridement. A flattened femoral head was detected during the follow-up, which became quite spherical a year after. An arthrotomy with medial synovectomy of the knee was performed in the second patient. Lack of full knee extension was presented during the first 3?months, which gradually decreased to 7° in the final follow-up. The suspicion of Mp infection with extra-pulmonary involvement in children is mainly based on clinical, epidemiological and radiological data, but laboratory testing is required for confirmation. Rapid diagnosis of probability consists of serum tests, and their results are essential for early therapeutic planning. The direct diagnosis of Mp DNA through polymerase chain reaction (PCR) provides specificity and sensitivity. Very few cases of arthritis associated with Mp infection have been published but not with the severity of our cases. Clinical suspicion of Mp infection is of great importance, and the outcome depends on early diagnosis and specific treatment.     

Laparoscopic versus open appendectomy in men: a prospective randomized trial

Background  

The role of laparoscopic treatment in acute appendicitis still is unclear. Although some evidence in the literature suggests diagnostic benefits from laparoscopy for young women with suspected acute appendicitis, there is scepticism about the utility of this approach for men. This study aimed to compare open and laparoscopic appendectomy performed for men with suspected acute appendicitis.     

Validity of SF-12 summary scores in a Greek general population

Background  

The 12-item Health Survey (SF-12) was developed as a shorter alternative to the SF-36 for use in large-scale studies, particularly when overall physical and mental health are the outcomes of interest instead of the typical eight-scale profile. The main purpose of this study was to assess the validity of the Greek version of the SF-12.     

Significance of estrogen receptors and cathepsin D tissue detection in gastric adenocarcinoma

Estrogen receptors (ERs) have recently been reported to be present in carcinomas of stomach, an organ that has so far been considered as nontarget for sex hormones. Cathepsin D is an estrogen-regulated lysosomal protease that has been overexpressed in breast cancer. ER and cathepsin D immunohistochemical expression were studied in this research in order to estimate their association to known histopathological and clinical parameters and their possible prognostic significance as well. Sixty-two patients with gastric adenocarcinomas were included in this study. The cancers were studied immunohistochemically concerning ER positivity in tumor cell nuclei and cathepsin D cytoplasmic expression. Nuclear ER staining was detected in tumor cells of 25% of male and 27% of female patients. ER positivity was demonstrated mainly in the well and moderately differentiated carcinomas; 87.5% of ER(+) tumors were also characterized as cathepsin D positive and a significant correlation between ER and cathepsin D positive expression was demonstrated (P < 0.05). Cytoplasmic cathepsin D expression was observed in carcinomatous cells of 70.9% of gastric tumors. Early tumor stage and good differentiation were significantly associated with increased cathepsin D expression (P < 0.05, P < 0.001). Histologic type, degree of differentiation and tumor stage were significantly correlated to survival (P < 0.05, P < 0.001 and P < 0.001). The patients who were cathepsin D(+) had a significant prognostic advantage over the cathepsin D(-) patients (P < 0.001). The presence of ER and estrogen-regulated cathepsin D indicates the involvement of sex hormonal factors in these tumors and cathepsin D positive expression in tumor cells seems to be related to better prognosis. Their biological, clinical, and prognostic roles remain to be further elucidated. © 1995 Wiley-Liss, Inc.     

Leydig cell tumors of the testis with unusual features: adipose differentiation,calcification with ossification,and spindle-shaped tumor cells

We report 19 Leydig cell tumors (LCTs) of the testis with adipose differentiation (n = 12) and/or spindle cell growth (n = 8) in patients 28-70 years of age; three tumors with adipose differentiation showed psammomatous calcifications, two of which also had foci of ossification. In eight tumors fat-like cells apparently derived from lipid accumulation within neoplastic Leydig cells and appeared as focal to prominent clusters in a background of vacuolated, neoplastic Leydig cells. The fat-like cells were usually immunoreactive for Leydig cell markers (inhibin-alpha, calretinin, and melan-A) but were typically strongly positive for the adipose tissue marker, S-100 protein, supporting a hybrid cell phenotype. Four tumors had fat of stromal derivation. In two of these there were intermixed mature adipocytes, but in two others only lipoblastic cells were present. These four tumors lacked vacuolated, neoplastic Leydig cells, and the fat cells in the single case studied were negative for inhibin-alpha and melan-A but positive for S-100. Three of the 12 LCTs with adipose differentiation were clinically malignant, and each had several of the established malignant features. Eight tumors with spindle cells occurred in men 34-70 years of age. Two tumors had ill-defined fascicles of spindle cells, and three showed prominent edematous to myxoid areas with spindle-shaped tumor cells. Two additional tumors had a fibroma-like spindled component that blended with islands of more plump, polygonal to spindle-shaped Leydig cells. Finally, one tumor had foci resembling an unclassified sarcoma that merged with conventional LCT; the spindle cell component in this case did not react for Leydig cell markers in contrast to the spindle cells in five of the six other cases in which immunostains were performed. Spindle cell differentiation, by itself, did not appear to have prognostic significance. Of the six patients with available follow-up, two developed metastases, but their tumors had malignant features apart from spindle cells; the remaining four patients were disease free at a mean of 3.6 years. Awareness of these unusual patterns in LCTs may prevent misinterpretation of fat admixed with neoplastic Leydig cells as evidence of extratesticular growth (a criterion for malignant LCT) may help avoid misdiagnosis of a LCT as a testicular "tumor" of the adrenogenital syndrome (which may contain fat) and may prevent misdiagnosis of a LCT with spindle cells as a sarcoma or unclassified sex cord-stromal tumor.     

Feature selection for structure-activity correlation using binary particle swarms

We present a new feature selection algorithm for structure-activity and structure-property correlation based on particle swarms. Particle swarms explore the search space through a population of individuals that adapt by returning stochastically toward previously successful regions, influenced by the success of their neighbors. This method, which was originally intended for searching multidimensional continuous spaces, is adapted to the problem of feature selection by viewing the location vectors of the particles as probabilities and employing roulette wheel selection to construct candidate subsets. The algorithm is applied in the construction of parsimonious quantitative structure-activity relationship (QSAR) models based on feed-forward neural networks and is tested on three classical data sets from the QSAR literature. It is shown that the method compares favorably with simulated annealing and is able to identify a better and more diverse set of solutions given the same amount of simulation time.     

A peroxyoxalate chemiluminescence-based assay for the evaluation of hydrogen peroxide scavenging activity employing 9,10-diphenylanthracene as the fluorophore

INTRODUCTION: A simple, rapid, sensitive, and enzyme-free analytical method for estimating scavenging of hydrogen peroxide (H2O2) was developed. METHODS: Peroxyoxalate chemiluminescence (POCL) was measured, using 9,10-diphenylanthracene as fluorophore. RESULTS: The chemiluminescence signal was found to be linear in response to increasing amounts of H2O2 in ethyl acetate/acetonitrile (9:1) (r2 = .9990), within a range of concentrations varying from 9.0 to 72.0 microM. In contrast, acetonitrile was highly unsuitable because of poor linearity (r2 = .3736) and poor signal stability. The linearity of POCL inhibition, as a measure of H2O2 scavenging, was tested employing well-known, lipid-soluble antioxidants, including beta-carotene, butylated hydroxytoluene (BHT) and alpha-tocopherol, and also the more polar flavonol quercetin, and the water-soluble L-ascorbic acid (AA). Under the experimental conditions, the corresponding values of H2O2 scavenging activity (SA(HP)) for quercetin, beta-carotene, alpha-tocopherol, and L-AA were 19.1 +/- 0.4, 70.9 +/- 20.1, 8.4 +/- 0.4, and 44.8 +/- 5.6 x 10(-3) microM(-1) DISCUSSION: The data establish the assay as a method for assessing the H2O2 quenching activity of lipid-soluble antioxidants.