Effect of preoperative pulmonary hemodynamic and cardiopulmonary bypass on lung function in children with congenital heart disease.

In children with congenital heart disease (CHD), pulmonary blood flow (Qp) contributes to alterations of pulmonary mechanics and gas exchange, while cardiopulmonary bypass (CPB) induces lung edema. We aimed to determine the effect of hemodynamics on lung function and lung epithelial lining fluid (ELF) biomarkers in biventricular CHD children undergoing CPB. CHD children were classified as high Qp (n = 43) and low Qp (n = 17), according to preoperative cardiac morphology and arterial oxygen saturation. We measured ELF surfactant protein B (SP-B) and myeloperoxidase activity (MPO) as indexes of lung inflammation and ELF albumin as index of alveolar capillary leak in tracheal aspirate (TA) samples collected before surgery and in 6 hourly intervals within 24 h after surgery. At the same time points, we recorded dynamic compliance and oxygenation index (OI). The same biomarkers were measured in TA samples collected from 16 infants with no cardiorespiratory diseases at the time of endotracheal intubation for elective surgery. Preoperative ELF biomarkers in CHD children were significantly increased than those found in controls. In the high Qp, ELF MPO and SP-B peaked 6 h after surgery and tended to decrease afterward, while they tended to increase within the first 24 h in the low Qp. ELF albumin peaked 6 h after surgery and decreased afterwards in both CHD groups. Dynamic compliance/kg and OI significantly improved after surgery only in the High Qp.  Conclusion: In CHD children, lung mechanics, OI, and ELF biomarkers were significantly affected by CPB, according to the preoperative pulmonary hemodynamics. What is Known: • Congenital heart disease children, before cardiopulmonary run, exhibit changes in respiratory mechanics, gas exchange, and lung inflammatory biomarkers that are related to the preoperative pulmonary hemodynamics. • Cardiopulmonary bypass induces alteration of lung function and epithelial lining fluid biomarkers according to preoperative hemodynamics. What is New: • Our findings can help to identify children with congenital heart disease at high risk of postoperative lung injury who may benefit of tailored intensive care strategies, such as non-invasive ventilation techniques, fluid management, and anti-inflammatory drugs that can improve cardiopulmonary interaction in the perioperative period.

Monofocal hepatocellular carcinoma: How much does size matter?

BACKGROUND & AIMS: According to the Barcelona Clinic Liver Cancer (BCLC) staging system, monofocal hepatocellular carcinoma (HCC) is classified as early (BCLC A) irrespective of its size, even though controversies still exist regarding staging and treatment of large tumours. We aimed at evaluating the appropriate staging and treatment for large (>5 cm) monofocal (HCC). METHODS: From the Italian Liver Cancer database, we selected 924 patients with small early monofocal HCC (2-5 cm; SEM-HCC), 163 patients with larger tumours (>5 cm; LEM-HCC) and 1048 intermediate stage patients (BCLC B). RESULTS: LEM-HCC patients had a worse overall survival (OS) than SEM-HCC (31.0 vs 49.0 months; P < .0001), and this was confirmed at multivariate analysis (HR 1.63, 95% CI 1.29-2.05; P < .0001). The small difference in OS between LEM-HCC and BCLC B patients (31.0 vs 27.0 months; P = .03) disappeared in the multivariate model (HR 0.98, 95% CI 0.77-1.25; P = .89). In all monofocal tumours, treatment was the strongest independent predictor of survival, with a progressively decreasing survival benefit moving from "curative" to "palliative" therapies. The survival of resected patients with LEM-HCC was significantly shorter than that of SEM-HCC (44.0 vs 78.0 months; P = .002), but liver resection provided the highest survival benefit in both groups compared to other treatments. CONCLUSIONS: Monofocal HCC larger than 5 cm should not be staged as BCLC A and either a different staging system or a different subgrouping of patients (e.g. BCLC AB) should be used. Liver resection, if feasible, remains the recommended treatment for all these patients.

Listeria monocytogenes transiently alters mitochondrial dynamics during infection.

Mitochondria are essential and highly dynamic organelles, constantly undergoing fusion and fission. We analyzed mitochondrial dynamics during infection with the human bacterial pathogen Listeria monocytogenes and show that this infection profoundly alters mitochondrial dynamics by causing transient mitochondrial network fragmentation. Mitochondrial fragmentation is specific to pathogenic Listeria monocytogenes, and it is not observed with the nonpathogenic Listeria innocua species or several other intracellular pathogens. Strikingly, the efficiency of Listeria infection is affected in cells where either mitochondrial fusion or fission has been altered by siRNA treatment, highlighting the relevance of mitochondrial dynamics for Listeria infection. We identified the secreted pore-forming toxin listeriolysin O as the bacterial factor mainly responsible for mitochondrial network disruption and mitochondrial function modulation. Together, our results suggest that the transient shutdown of mitochondrial function and dynamics represents a strategy used by Listeria at the onset of infection to interfere with cellular physiology.

Circulating MicroRNA-21 and MicroRNA-122 as Prognostic Biomarkers in Hepatocellular Carcinoma Patients Treated with Transarterial Chemoembolization.

BACKGROUND: MicroRNAs (miRNAs) have been proposed as biomarkers in hepatocellular carcinoma (HCC). We aim at evaluating miR-21 and miR-122 in HCC patients treated with drug-eluting beads transarterial chemoembolization (DEB-TACE) as prognostic biomarkers and investigating their correlation with hypoxia inducible factor-1α (HIF-1α) serum levels. METHODS: In this retrospective study, 12 healthy subjects, 28 cirrhotics, and 54 HCC patients (tested before and four weeks after DEB-TACE) were included. Whole blood miR-21 and miR-122 levels were measured by quantitative real time (qRT)-PCR, while serum HIF-1α was assessed by an enzyme-linked immunosorbent assay (ELISA) test. RESULTS: The highest level of miR-21 was found in cirrhotics, while HCC patients had the highest level of miR-122 (which was even higher in "viral" HCC, p = 0.006). miR-21 ratio (after/before DEB-TACE) and miR-122 below their respective cut-offs identified patients with longer progression-free survival (p = 0.0002 and p = 0.02, respectively). The combined assessment of alpha-fetoprotein and miR-21 ratio, both independent prognostic predictors, identified early progressors among patients with complete or partial radiological response. miR-21 levels positively correlated with HIF-1α before (p = 0.045) and after DEB-TACE (p = 0.035). CONCLUSIONS: miR-21 ratio and miR-122 are useful prognostic markers after DEB-TACE. miR-21 correlates with HIF-1α and probably has a role in modulating angiogenesis in HCC.

Surveillance as Determinant of Long-Term Survival in Non-Transplanted Hepatocellular Carcinoma Patients.

PURPOSE: We aimed at assessing the impact of surveillance on long-term survival in HCC patients. METHODS: From the ITA.LI.CA database, we selected 1028 cases with long (≥5 years, LS group) and 2721 controls with short-term survival (<5 years, SS group). The association between surveillance and LS was adjusted for confounders by multivariable logistic regression analysis. Survival of surveilled patients was presented both as observed and corrected for the lead-time bias, and the comparison of survival between surveillance and no surveillance groups was also performed after balancing the baseline characteristics with inverse probability weights (IPW). RESULTS: LS patients were more frequently diagnosed under surveillance (p < 0.0001), and had more favorable baseline characteristics. Surveillance was an independent predictor of LS (OR = 1.413, 95% CI 1.195-1.671; p < 0.0001). The observed and the lead-time corrected survival of surveilled patients were significantly longer compared to the survival of not surveilled patients (p < 0.0001 and p = 0.0008, respectively). In IPW adjusted populations, no survival differences were demonstrated between the two groups (p = 0.30). CONCLUSIONS: Surveillance, increasing early-stage diagnosis and applicability of curative treatments, is a fundamental determinant of long-term survival in HCC patients. A wide implementation of surveillance programs should be pursued in order to improve HCC patients' prognosis.

SCCA-IgM in hepatocellular carcinoma patients treated with transarterial chemoembolization: gender-related differences.

Aim: Squamous cell carcinoma antigen immune complexed with immunoglobulin M (SCCA-IgM) is a useful but not completely satisfactory biomarker of hepatocellular carcinoma (HCC). Considering its gender-specific behavior in preclinical models, we investigated gender-related differences of SCCA-IgM as a prognostic marker in HCC. Patients & methods: Two hundred and eight prospectively recruited patients treated with transarterial chemoembolization in a single tertiary care hospital were retrospectively evaluated. Correlations between SCCA-IgM levels, clinical characteristics and survival were assessed according to gender. Results: When the disease was advanced, SCCA-IgM was higher in males and lower in females. Levels below 130 AU/ml predicted a significantly longer survival in males (p = 0.007) and a shorter survival in females (p = 0.01). Conclusion: In predicting the prognosis of HCC patients, the interpretation of SCCA-IgM should consider gender as a relevant variable.

Capecitabine in advanced hepatocellular carcinoma: A multicenter experience.

BACKGROUND: Recent data suggest a potential activity and a good tolerability of capecitabine in advanced hepatocellular carcinoma (HCC). AIMS: To evaluate capecitabine activity and safety in a wide cohort of advanced HCC patients. METHODS: Retrospective analysis of 143 capecitabine-treated patients (January 2010 to December 2017) in three centers of the Veneto Oncology Network. RESULTS: Capecitabine was administered in second and third line, but also in first line instead of sorafenib in Child-Pugh B patients (70%), compromised clinical conditions (14%) or contraindications to antiangiogenetics (16%). Median overall survival (OS) and time to progression (TTP) were 6.9 and 2.8 months, respectively. There were no differences in OS and TTP between the 32 patients treated with non-metronomic scheme (2000 mg/day for 14 days) and the 111 patients treated with metronomic scheme (1000 mg/day) after correction for prognostic factors at baseline with a propensity score analysis. Capecitabine was more active in patients intolerant to sorafenib than in those progressing during treatment (p = 0.024). At least one adverse event (mainly hematological) was experienced by 73% of patients but discontinuation was necessary only in 11 (8%). CONCLUSIONS: Capecitabine can be considered an active and safe option in advanced HCC, especially for patients unfit for other treatments.

Clathrin phosphorylation is required for actin recruitment at sites of bacterial adhesion and internalization.

Bacterial pathogens recruit clathrin upon interaction with host surface receptors during infection. Here, using three different infection models, we observed that host-pathogen interactions induce tyrosine phosphorylation of clathrin heavy chain. This modification was critical for recruitment of actin at bacteria-host adhesion sites during bacterial internalization or pedestal formation. At the bacterial interface, clathrin assembled to form coated pits of conventional size. Because such structures cannot internalize large particles such as bacteria, we propose that during infection, clathrin-coated pits serve as platforms to initiate actin rearrangements at bacteria-host adhesion sites. We then showed that the clathrin-actin interdependency is initiated by Dab2 and depends on the presence of clathrin light chain and its actin-binding partner Hip1R, and that the fully assembled machinery can recruit Myosin VI. Together, our study highlights a physiological role for clathrin heavy chain phosphorylation and reinforces the increasingly recognized function of clathrin in actin cytoskeletal organization in mammalian cells.

Entrapment of intracytosolic bacteria by septin cage-like structures.

Actin-based motility is used by various pathogens for dissemination within and between cells. Yet host factors restricting this process have not been identified. Septins are GTP-binding proteins that assemble as filaments and are essential for cell division. However, their role during interphase has remained elusive. Here, we report that septin assemblies are recruited to different bacteria that polymerize actin. We observed that intracytosolic Shigella either become compartmentalized in septin cage-like structures or form actin tails. Inactivation of septin caging increases the number of Shigella with actin tails and enhances cell-to-cell spread. TNF-α, a host cytokine produced upon Shigella infection, stimulates septin caging and restricts actin tail formation and cell-to-cell spread. Finally, we show that septin cages entrap bacteria targeted to autophagy. Together, these results reveal an unsuspected mechanism of host defense that restricts dissemination of invasive pathogens.

Multiscale imaging of neurons grown in culture: from light microscopy to cryo-electron tomography.

Cryo-electron tomography (cryo-ET) allows the visualization of supramolecular architecture in cells preserved in a close-to-physiological state. In order to supplement the structural information obtained by cryo-ET with the functional state of the molecules involved based on fluorescent labeling we developed a method of correlating light microscopy and cryo-ET. This method is suitable for investigating complicated cellular landscapes such as mature neurons grown in culture. It has the advantage that a correlation is obtained without exposing a feature of interest to additional electron irradiation, and that it does not rely on visual recognition of features. Different modes of correlation are presented here: a feature identified on a light microscopy image is used to guide the cryo-ET investigation, and cryo-tomograms are correlated to light microscopy images. Cryo-tomograms of a neuronal synapse and of an isolated presynaptic terminal are shown as examples of the correlative method. The correlation method presented here can be expected to provide new insights into the structure-function relationship of supramolecular organization in neurons.

Correlative microscopy: bridging the gap between fluorescence light microscopy and cryo-electron tomography.

Cryo-electron tomography of frozen-hydrated biological samples offers a means of studying large and complex cellular structures in three-dimensions and with nanometer-scale resolution. The low contrast of unstained biological material embedded in amorphous ice and the need to minimise the exposure of these radiation-sensitive samples to the electron beam result in a poor signal-to-noise ratio. This poses problems not only in the visualisation and interpretation of such tomograms, it is also a problem in surveying the sample and in finding regions which contain the features of interest and which are suitable for recording tomograms. To address this problem, we have developed a correlative fluorescence light microscopy-electron microscopy approach, which guides the search for the structures of interest and allows electron microscopy to zoom in on them. With our approach, the total dose spent on locating regions of interest is negligible. A newly designed cryo-holder allows imaging of fluorescently labelled samples after vitrification. The absolute coordinates of structures identified and located by cryo-light microscopy are transferred to the electron microscope via a Matlab-based user interface. We have successfully tested the experimental setup and the whole procedure with two types of adherent fluorescently labelled cells, a neuronal cell line and keratinocytes, both grown directly on EM grids.

Sieving mechanisms in polymeric matrices.

A critical review of the existing theoretical models and experimental evidences for sieving mechanisms during separation of macromolecules, paying particular attention to capillary electrophoresis applications is presented. Gel models (Ogston and reptation) have been successfully applied to highly entangled polymer solutions, where fast and efficient separations can occur. In order to account for the DNA/polymers collision-interaction mechanisms during separation in dilute solutions - characterized by a poorer resolution -, approximated analytical models have been developed. An insight in the mechanism regulating the intermediate case of moderately entangled polymer solutions, for low fields and concentrations of small multiples of the overlap concentration c*, is given by the constraint release approach. This model proposes an upper limit of size separation, increasing with matrix concentration and molecular mass. Finally, the coupling between the reptative motion of the analytes and the effect of matrix constraint release very likely plays a fundamental role in the separation mechanism and requires therefore further and deeper investigation, both theoretically and experimentally.