Tumor necrosis factor alpha (TNF) is a cytokine that induces caspase-dependent (apoptotic) and caspase-independent (necrosis-like) cell death in different cells. We used the murine fibrosarcoma cell line model L929 and a stable L929 transfectant over-expressing a mutated dominant-negative form of BNIP3 lacking the C-terminal transmembrane (TM) domain (L929-DeltaTM-BNIP3) to test if TNF-induced cell death involved pro-apoptotic Bcl2 protein BNIP3. Treatment of cells with TNF in the absence of actinomycin D caused a rapid fall in the mitochondrial membrane potential (DeltaPsim) and a prompt increase in reactive oxygen species (ROS) production, which was significantly less pronounced in L929-DeltaTM-BNIP3. TNF did not cause the mitochondrial release of apoptosis inducing factor (AIF) and Endonuclease G (Endo-G) but provoked the release of cytochrome c, Smac/Diablo, and Omi/HtrA2 at similar levels in both L929 and in L929-DeltaTM-BNIP3 cells. We observed TNF-associated increase in the expression of BNIP3 in L929 that was mediated by nitric oxide and significantly inhibited by nitric oxide synthase inhibitor N5-(methylamidino)-L-ornithine acetate. In L929, lysosomal swelling and activation were markedly increased as compared to L929-DeltaTM-BNIP3 and could be inhibited by treatment with inhibitors to vacuolar H+-ATPase and cathepsins -B/-L. Together, these data indicate that TNF-induced cell death involves BNIP3, ROS production, and activation of the lysosomal death pathway.

Abstract.Objectives : The phosphatidylinositol 3-kinase (PI3-K)/Akt pathway is well known for the regulation of cell survival, proliferation, and some metabolic routes. Meterials and Methods : In this study, we document a novel role for the PI3-K/Akt pathway during cell death induced by apoptin, a tumour-selective inducer of apoptosis. Results : We show for the first time that apoptin interacts with the p85 regulatory subunit, leading to constitutive activation of PI3-K. The inhibition of PI3-K activation either by chemical inhibitors or by genetic approaches severely impairs cell death induced by apoptin. Downstream of PI3-K, Akt is activated and translocated to the nucleus together with apoptin. Direct interaction between apoptin and Akt is documented. Co-expression of nuclear Akt significantly potentiates cell death induced by apoptin. Thus, apoptin-facilitated nuclear Akt, in contrast to when in its cytoplasmic pool, appears to be a positive regulator, rather than repressor of apoptosis. Conclusions : Our observations indicate that PI3-K/Akt pathways have a dual role in both survival and cell death processes depending on the stimulus. Nuclear Akt acts as apoptosis stimulator rather than as a repressor, as it likely gains access to a new set of substrates in the nucleus. The implicated link between survival and cell death pathways during apoptosis opens new pharmacological opportunities to modulate apoptosis in cancer, for example through the manipulation of Akt's cellular localization.

Vocal cord paralysis is a common complication in patients undergoing open surgery of the aortic arch and descending aorta, and is associated with significant morbidity. Further research may be warranted to determine if early fiberoptic examination and consideration of a vocal cord medialization procedure may mitigate the morbidity associated with VCP.

We built a natural language processing (NLP) method to automatically extract clinical findings in radiology reports and characterize their level of change and significance according to a radiology-specific information model. We utilized a combination of machine learning and rule-based approaches for this purpose. Our method is unique in capturing different features and levels of abstractions at surface, entity, and discourse levels in text analysis. This combination has enabled us to recognize the underlying semantics of radiology report narratives for this task. We evaluated our method on radiology reports from four major healthcare organizations. Our evaluation showed the efficacy of our method in highlighting important changes (accuracy 99.2%, precision 96.3%, recall 93.5%, and F1 score 94.7%) and identifying significant observations (accuracy 75.8%, precision 75.2%, recall 75.7%, and F1 score 75.3%) to characterize radiology reports. This method can help clinicians quickly understand the key observations in radiology reports and facilitate clinical decision support, review prioritization, and disease surveillance.