Hepatopulmonary syndrome with right-to-left shunt in cirrhotic patients using macro-aggregated albumin lung perfusion scan: Comparison with contrast echocardiography and association with clinical data [Sirotik hastalardaki sağ-sol şant ile ilişkili hepatopulmoner sendromun tanısında makro-agregant albümin akciğer perfüzyon sintigrafisinin kontrast ekokardiyografi ile karşılaştırılması ve klinik veriler ile ilişkisi]

Objectives: The diagnosis of hepatopulmonary syndrome (HPS) which is a common complication in cirrhotic patients is still subject to debate. This study investigated the association of clinical findings with HPS in cirrhotic patients using macro-aggregated albumin lung perfusion scan (99mTc-MAA lung scintigraphy). In addition, comparison between99mTc-MAA lung scintigraphy and contrast echocardiography (CEE) in detection of HPS was also performed. Methods: In this study, 27 patients with cirrhosis underwent99mTc-MAA lung scintigraphy and contrast echocardiography comparison CEE and the frequency of HPS was assessed in them and also was compared across the other variables. Results: The99mTc-MAA lung scintigraphy showed HPS in 13 patients (48.1%) while CEE demonstrated HPS in 5 patients with cirrhosis (18.51%). HPS was mild in 40.74% (11/27) of the patients, and severe in only 2 patients. There was no relationship between gender, disease duration, having diagnosis of disease previously, pulmonary symptoms and Child-Pugh score variations and HPS (p>0.05). Comparison of hemodynamic indices, arterial blood gas analysis and laboratory indices between patients with and without HPS was also non-significant (p value >0.05). Among coagulation factors assessed in cirrhotic patients, we found only significant correlation between HPS and prothrombin time (p<0.05). Conclusion: HPS, particularly its mild form, is noted in a great number of patients with cirrhosis using 99mTc-MAA lung scintigraphy. Because of its technical ease, and possibility to obtain objective quantitative information,99mTc-MAA lung scintigraphy can be complementary to other diagnostic methods in the evaluation of HPS assessment, although additional studies are needed

Numerical investigation of non-homogenous wettability alteration in naturally fractured rocks

Wettability alteration is one of the most promising techniques to enhance oil recovery of oil-wet reservoirs. As contact angle decreases within the matrix, the flux of fracture-matrix counter-current imbibition increases significantly (Sedaghat et al., ECMOR 2016). However, wettability altering agent only influences the wettability of a portion of the matrix region, and not necessarily uniformly. The agent (water phase) makes the fractures and surrounding matrix water-wet, but this alteration is gradually reduced with the distance from the fracture-matrix interface. Beyond the fracture-matrix imbibition halo, wettability (contact angle) does not change anymore. So, this wettability transition zone needs to be considered when simulation of multiphase flow in naturally fractured rocks is performed. Utilizing a Finite-Element-Centered-Finite-Volume (FECFV) numerical approach, we simulated a waterflooding scenario on a discrete fracture and matrix (DFM) model built based on an outcrop analogue. First, a wettability altering agent is flooded into the system until the change in the saturation gets negligible. The system is then equilibrated in a given time period. By weighting contact angle with wetting fluid saturation, wettability is updated for each element at the equilibrium state. Finally, waterflooding is performed with the updated wettability. Assuming that the wettability altering agent has 100% performance, it does not influence water properties and requires a considerable time to change the wettability. Therefore, reactive transport is left out of the computations. Compare to the results of base case model in which wettability transition zone was neglected (Sedaghat et al., ECMOR 2016), partial wettability alteration associated with a non-homogenous distribution of contact angle significantly influences the oil recovery, fracture-matrix counter-current imbibition, and ensemble relative permeability. Moreover, velocity fluxes and flow behaviour is influenced dramatically as it leads to a heterogeneous distribution of capillary pressure over the matrix within the fracture-matrix counter-current imbibition halos

How fracture capillary pressure affects ensemble relative permeability of naturally fractured reservoirs

This work presents a significant advance over earlier methods because it employs a surface-roughness based fracture dilation model to compute aperture distributions. From these, fracture capillary pressure is computed before saturation functions are extracted. This upscaling is performed using an unsteady state approach to evaluate the impact of fracture capillary pressure on ensemble relative permeability and ultimate recovery. The simulation approach is applied to outcrop-based meter-And kilometre-scale DFM models. For these fracture geometries, aperture attributes are computed for plausible regimes of in situ stress. Corresponding capillary pressure values are assigned to individual fractures. The capillary pressure of the rock matrix is parameterized with representative data for siliciclastics and carbonates. The twophase flow simulations are performed with the Finite Element-Centered Finite Volume Method (FECFVM). Flow-based upscaling establishes ensemble relative permeability between capillary and viscous limits. Based on results, for a water-wet rock matrix, there is more fracture-matrix transfer and oil recovery is higher. Counter-current-imbibition flux is diminished gradually since the small fractures that dominate the fracture-matrix interface area have drastically smaller fracture-matrix pressure differentials. These differences become more pronounced near the capillary limit. As the wettability tends to the oil, two phase flow occurs within a narrower range of saturation

Does the symmetry of absolute permeability influence relative permeability tensors in naturally fractured rocks?

Relative permeability is a tensorial property directly dependent on absolute permeability tensor which has been taking both symmetric and non-symmetric (full tensor) forms in the literature. Imposing symmetricity during upscaling absolute and effective phase permeabilities could alter both diagonal and off-diagonal terms of relative permeability tensors, specifically in naturally fractured reservoirs (NFRs) where the diagonal components of the permeability tensor could take values with different orders of magnitude. Utilizing a discrete fracture and matrix (DFM) modelling approach, in this paper, we quantify the effects of forcing the symmetricity on absolute permeability tensors on relative permeability tensors of fractured samples in different scales. We also determine the circumstances at which this change in methodology causes a huge difference in the diagonal components of relative permeability tensors

Tensorial fracture-matrix ensemble relative permeabilities in naturally fractured reservoirs: evidence from discrete fracture and matrix simulations

The prediction of water breakthrough and oil recovery for naturally fractured reservoirs (NFRs) cannot be performed accurately without dynamic upscaled relative permeability functions. Relative permeability is commonly assumed to be a scalar quantity, although a justification for NFRs has yet to be presented. In this study, we show how accurate this assumption is for fracture-matrix ensemble relative permeabilities determined by numeric simulations of unsteady-state core flooding. Numerical determination of relative permeability requires a realistic flow model, a spatially adaptive simulation approach and a sophisticated analysis procedure. To fulfil these requirements, we apply discrete fracture and matrix modelling to well characterised hm-km outcrop analogues. These are parametrized with aperture, permeability, and capillary pressure data. Fracture attributes are allowed to vary from segment to segment, trying to emulate in situ conditions. The finite-element-centered-finite-volume method is used to simulate two-phase flow in the fractured rock, considering different wettability conditions. Our results indicate that the ensemble relative permeability of 2D digital NFR outcrop analog models is a tensor property. The tensors are not necessarily symmetric, and their eigenvalues are not always equal to the diagonal terms. Also, the off-diagonal terms can determine the type, i.e., counter vs co-current imbibition, and the direction of imbibition

The role of cognitive group therapy and happiness training on cerebral blood flow using 99mTc-ECD brain perfusion SPECT: A quasi-experimental study of depressed patients

Abstract Objective: The purpose of this study is to investigate the impact of cognitive group therapy and happiness training objectively in the local cerebral blood flow of patients with major depression (MD). Patients, material, methods: The present research is semi-experimental to pre- and post-test with a control group. Three groups were formed, and this number was incorporated in each group: 12 patients were chosen randomly; the first group of depressed patients benefited from the combination of pharmacotherapy and sessions of cognitive group therapy; the second group used a combination of pharmaco-therapy and sessions of happiness training; and a third group used only pharmacother-apy. We compared cognitive-behavioural therapy and happiness training efficacy with only pharmacotherapy in MD patients. We performed brain perfusion SPECT in each group, before and after each trial. Results: The study was conducted on 36 patients with MD (32 women and 4 men; mean age: 41.22 ± 9.08; range: 27–65 years). There were significant differences regarding the two trial effects into two experimental groups (p 0.05). In addition, there was significant difference among the regional cerebral blood flow in the frontal and prefrontal regions into two experimental groups before and after trials (p 0.05). Conclusion: This study demonstrated decreased cerebral perfusion in the frontal regions in MD patients, which increased following cognitive group therapy and happiness training. Because of its availability, low costs, easy performance, and the objective semi-quantitative information supplied, brain perfusion SPECT scanning might be useful to assess the diagnosis and therapy efficacy. Further exploration is needed to validate its clinical role. © Schattauer 2014

A novel chromonyl thiohydantoin with anti-proliferative action on primary hepatocellular carcinoma cells

Chromone, imidazolidinedione, thiohydantoin and 2,4-thiazolidinedione structures are known to be cytotoxic to cancer cells. In this study, biological activities of previously synthesized 18 chromonyl-2,4-thiazolidinediones/imidazolidinediones/thiohydantoins were tested by sulforhodamine B assay in five liver and one breast cancer cell lines. It was shown that a hybrid chromonyl thiohydantoin derivative C9 was able to significantly suppress the proliferation of the liver cancer cell lines which are very resistant to anticancer drugs. According to 50% growth inhibition concentrations of C9, well differentiated hepatocellular carcinoma cell line Huh7 and breast adenocarcinoma cell line Mcf7 cells are found to be highly sensitive to C9 with IC50 values between 4.9-5.2 mu M. Poorly differentiated human liver cancer cell line Snu449 is found to be the most resistant to C9. Further studies show that C9 causes morphological changes in Snu449 cells. However, it does not induce significant senescence response or cell cycle arrest. On the other hand, Huh7 cells are found to be arrested in G2/M phase of the cell cycle after 24 and 72 h treatment. In conclusion, a novel chromonyl thiohydantoin hybrid molecule effectively stops or slows down the proliferation of well-differentiated hepatocellular carcinoma cells that exist in primary tumors