44 research outputs found
Simultaneous Inhibition of Mcl-1 and Bcl-2 Induces Synergistic Cell Death in Hepatocellular Carcinoma
Despite the recent approval of new therapies, the prognosis for patients with hepatocellular carcinoma (HCC) remains poor. There is a clinical need for new highly effective therapeutic options. Here, we present a combined application of BH3-mimetics as a potential new treatment option for HCC. BH3-mimetics inhibit anti-apoptotic proteins of the BCL-2 family and, thus, trigger the intrinsic apoptosis pathway. Anti-apoptotic BCL-2 proteins such as Bcl-2 and Mcl-1 are frequently overexpressed in HCC. Therefore, we analyzed the efficacy of the two BH3-mimetics ABT-199 (Bcl-2 inhibitor) and MIK665 (Mcl-1 inhibitor) in HCC cell lines with differential expression levels of endogenous Bcl-2 and Mcl-1. While administration of one BH3-mimetic alone did not substantially trigger cell death, the combination of two inhibitors enhanced induction of the intrinsic apoptosis pathway. Both drugs acted synergistically, highlighting the effectivity of this specific BH3-mimetic combination, particularly in HCC cell lines. These results indicate the potential of combining inhibitors of the BCL-2 family as new therapeutic options in HCC
Degradation studies of modified inulin as potential encapsulation material for colon targeting and release of mesalamine
Due to the potential to treat colon specific diseases with reduced side effects, colon targeting has become of high interest over the last decades. Chemical modified inulin was investigated for its potential as encapsulation material regarding its enzymatic degradability and its drug release behavior. Different degrees of acetylated inulin (degree of substitution, DS, 0.3–2.1) were synthesized. The chemical modification leads to a reduction in enzymatic degradability by inulinase and esterase, enzymes which can be expressed by the colon microbiota. Acetylated inulin was only hydrolyzed to fructose units up to DS of 1.3. Microparticles made of native inulin and acetylated inulin (DS 1.8) were loaded with the colon-specific drug mesalamine by spray drying. Compared to the burst release of mesalamine by inulin particles within 6 h, acetylated inulin particles showed less burst release followed by a continuous drug release phase caused by diffusion up to 30% mesalamine after 52 h
Intraoperative imaging for remnant viability assessment in bilateral posterior retroperitoneoscopic partial adrenalectomy in an experimental model
Fluorescence-enabled assessment of adrenal gland localization and perfusion in posterior retroperitoneoscopic adrenal surgery in a preclinical model
Amnésia por infusão pós-treino de antagonistas de receptores glutamatérgicos na amigdala, hipocampo e córtex entorrinal
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Amnésia por infusão pós-treino de antagonistas de receptores glutamatérgicos na amigdala, hipocampo e córtex entorrinal
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Intraoperative imaging for remnant viability assessment in bilateral posterior retroperitoneoscopic partial adrenalectomy in an experimental model
Background: A surgical approach preserving functional adrenal tissue allows biochemical cure while avoiding the need for lifelong steroid replacement. The aim of this experimental study was to evaluate the impact of intraoperative imaging during bilateral partial adrenalectomy on remnant perfusion and function. Methods: Five pigs underwent bilateral posterior retroperitoneoscopic central adrenal gland division (9 divided glands, 1 undivided). Intraoperative perfusion assessment included computer-assisted quantitative fluorescence imaging, contrast-enhanced CT, confocal laser endomicroscopy (CLE) and local lactate sampling. Specimen analysis after completion adrenalectomy (10 adrenal glands) comprised mitochondrial activity and electron microscopy. Results: Fluorescence signal intensity evolution over time was significantly lower in the cranial segment of each adrenal gland (mean(s.d.) 0·052(0·057) versus 0·133(0·057) change in intensity per s for cranial versus caudal parts respectively; P = 0·020). Concordantly, intraoperative CT in the portal phase demonstrated significantly lower contrast uptake in cranial segments (P = 0·031). In CLE, fluorescein contrast was observed in all caudal segments, but in only four of nine cranial segments (P = 0·035). Imaging findings favouring caudal perfusion were congruent, with significantly lower local capillary lactate levels caudally (mean(s.d.) 5·66(5·79) versus 11·58(6·53) mmol/l for caudal versus cranial parts respectively; P = 0·008). Electron microscopy showed more necrotic cells cranially (P = 0·031). There was no disparity in mitochondrial activity (respiratory rates, reactive oxygen species and hydrogen peroxide production) between the different segments. Conclusion: In a model of bilateral partial adrenalectomy, three intraoperative imaging modalities consistently discriminated between regular and reduced adrenal remnant perfusion. By avoiding circumferential dissection, mitochondrial function was preserved in each segment of the adrenal glands. Surgical relevance Preservation of adrenal tissue to maintain postoperative function is essential in bilateral and hereditary adrenal pathologies. There is interindividual variation in residual adrenocortical stress capacity, and the minimal functional remnant size is unknown. New intraoperative imaging technologies allow improved remnant size and perfusion assessment. Fluorescence imaging and contrast-enhanced intraoperative CT showed congruent results in evaluation of perfusion. Intraoperative imaging can help to visualize the remnant vascular supply in partial adrenalectomy. Intraoperative assessment of perfusion may foster maximal functional tissue preservation in bilateral adrenal pathologies and procedures. © 2020 The Authors. British Journal of Surgery published by John Wiley & Sons Ltd on behalf of BJS Society Ltd