Textural analysis in the diagnosis of benign and malignant breast cells.

OBJECTIVE: To study the discriminatory capacity of textural variables to classify the nuclei of breast tumor cells as benign or malignant, using a statistical approach. STUDY DESIGN: Image analysis techniques were used to automatically segment nuclei of cells obtained by fine needle aspiration and Papanicolaou stained. The sample comprised 95 cases of malignant lesions and 47 cases of benign lesions (approximately 25 nuclei per case), and 27 textural variables were measured. Two methods were used to analyze the data: classification and regression trees (CART) and discriminant analysis. RESULTS: The variance in gray levels was the most decisive variable in the CART analysis, correctly classifying 57% and 97% of benign and malignant cases, respectively. Discriminant analysis yielded the best results, correctly classifying 79% and 85% of benign and malignant cases, respectively. CONCLUSION: The classifier obtained by a statistical approach to the textural analysis of Papanicolaou-stained nuclei did not prove useful for diagnostic discrimination. Staining techniques that are not chromatin specific are highly variable, and other features have proven more effective with this type of staining.

Intermittent alveolar overdistension for 30 or 240 minutes does not produce acute lung injury in normal pig lung.

BACKGROUND: The objective is to study whether alveolar overdistension can induce acute lung injury in pigs as assessed by analysis of respiratory and histological parameters and inflammatory markers. MATERIALS AND METHODS: Experimental study, using mixed-breed pigs. Animals were assigned to one of the following groups: Control Group (CG) (n = 5), applying mechanical ventilation with tidal volume (Vt) of 10 ml/kg, respiratory rate (RR) of 18 bpm, and FiO2 of 1 for 240 min; High Vt for 30 min (HVt-30) Group (n = 5), applying ventilation with Vt of 50 ml/kg and RR of 8 bpm and FiO2 of 1 for 30 min, followed by ventilation as in the CG for a further 210 min; and HVt-240 Group (n = 5), applying ventilation with Vt of 50 ml/kg, RR of 8 bpm, and FiO2 of 1 for 240 min. Hemodynamic parameters, airway pressures, arterial blood gases, extravascular lung water (EVLW), and cytokines (IL-2, IL-4, IL-6, IL-10, TNF-alpha, and ITF-gamma) in plasma and bronchoalveolar lavage (BAL) were determined. Lungs were fixed with 10% formalin for histological analysis. Results are expressed as mean +/- standard deviation. The ANOVA test was used to compare measurements among the three groups. RESULTS: At 30 min, airway pressures and oxygenation of HVt-30 and HVt-240 groups were higher than those of controls [Pplateau: 39.2 +/- 5.6 and 33.0+/- 5.1 versus 12.2 +/- 1.3 (P < 0.01); PaO2/FiO2: 443.8 +/- 55 and 430.6 +/- 34 versus 194.4 +/- 77 (P < 0.01)]. In HVt-240 group, these parameters were also higher than in the other two groups at the subsequent measurement times. There were no differences among the groups in EVLW values. Cytokines were undetected or negligible in plasma and BAL in all of the groups. The histological analysis showed no changes suggestive of acute lung injury. CONCLUSIONS: In this animal model, ventilation for 4 h with large tidal volume did not cause ventilator-induced lung injury.