Texture image analysis in differentiating malignant from benign adrenal cortical tumors in children and adults.

OBJECTIVE: To investigate the possible role of chromatin texture parameters, nuclear morphology, DNA ploidy and clinical functional status in discriminating benign from malignant adrenocortical tumors (ACT). PATIENTS AND METHODS: Forty-eight cases of clinically benign (n=40) and clinically malignant (n=8) ACT with a minimum of 5-years' follow-up were evaluated for chromatin texture parameters (run length, standard deviation, configurable run length, valley, slope, peak and other 21 Markovian features that describe the distribution of the chromatin in the nucleus), nuclear morphology (nuclear area, nuclear perimeter, nuclear maximum and minimum diameter, nuclear shape), and DNA ploidy. Nuclear parameters were evaluated in Feulgen-stained 5 mum paraffin-sections analyzed using a CAS 200 image analyzer. RESULTS: Since ACTs present different biological features in children and adults, patients were divided into two groups: children (< or = 15 years) and adults (>15 years). In the group of children DNA ploidy presented a marginal significance (p=0.05) in discriminating ACTs. None of the parameters discriminated between malignant and benign ACT in the adult group. CONCLUSION: ACTs are uncommon and definitive predictive criteria for malignancy remain uncertain, particularly in children. Our data point to DNA content evaluated by image analysis as a new candidate tool for this challenging task. Texture image analysis did not help to differentiate malignant from benign adrenal cortical tumors in children and adults.

Rifabutin encapsulated in liposomes exhibits increased therapeutic activity in a model of disseminated tuberculosis.

Tuberculosis (TB) is a leading cause of death amongst infectious diseases. The low permeation of antimycobacterial agents and their difficult access to infected macrophages necessitate long-term use of high drug doses. Liposomes preferentially accumulate in macrophages, increasing the efficacy of antibiotics against intracellular parasites. In the present work, several rifabutin (RFB) liposomal formulations were developed and characterised and their in vivo profile was compared with free RFB following intravenous administration. With the RFB liposomal formulations tested, higher concentrations of the antibiotic were achieved in liver, spleen and lungs 24h post administration compared with free RFB. The concentration of RFB in these organs was dependent on the rigidity of liposomal lipids. The liposomal RFB formulation prepared with dipalmitoyl phosphatidylcholine:dipalmitoyl phosphatidylglycerol (DPPC:DPPG) was the most effective and was selected for biological evaluation in a mouse model of disseminated TB. Compared with mice treated with free RFB, mice treated with the DPPC:DPPG RFB formulation exhibited lower bacterial loads in the spleen (5.53 log(10) vs. 5.18 log(10)) and liver (5.79 log(10) vs. 5.41 log(10)). In the lung, the level of pathology was lower in mice treated with encapsulated RFB. These results suggest that liposomal RFB is a promising approach for the treatment of extrapulmonary TB in human immunodeficiency virus co-infected patients.