Laparoscopic Surgery for Gastric Cancer

In patients with gastric cancer, surgical resection is the only treatment that can offer cure or increase long-term survival. With the accumulation of experience in laparoscopic radical gastrectomy and the progress in surgical instruments, laparoscopic surgery for gastric cancer has gained popularity despite initial concerns regarding safety and oncological adequacy. As a result, laparoscopic technique has been widely applied in gastric cancer. Different meta-analyses showed that laparoscopic procedures are associated with less blood loss but longer operation time. Many studies have reported outcomes of laparoscopic surgery for early gastric cancer, but several authors also have shown that a laparoscopic approach can also be used in cases of advanced gastric cancer. We therefore conducted this study to expand our experience and to evaluate laparoscopic gastrectomy step by step in the light of recent reports while defining key points and surgical technique

Derivation of Analytical Fragility Curves for RC Buildings Based on Nonlinear Pushover Analysis

Fragility curves are widely used in estimation of various damage states that may occur in buildings during possible earthquakes. In this study, analytical fragility curves are derived by considering architectural and structural details of three to eight story reinforced concrete buildings, which constitute the major part of the existing building stock in the city of Izmir and are used for residential purpose. Nonlinear static analyses are performed by generating 3D models of the buildings. Spectral displacement demand of the buildings is determined for different earthquake levels, which are defined in the Turkish Seismic Design Code-2007. Four limit states are defined for each building class in terms of spectral displacement. The fragility curves, which reflect general characteristics of the existing building stock and are expressed in the form of two-parameter lognormal distribution functions, are presented as an outcome

A study on determination of target displacement of RC frames using PSV spectrum and energy-balance concept

The objective of this paper is to present an energy-based method for calculating target displacement of RC structures. The method, which uses the Newmark-Hall pseudo-velocity spectrum, is called the "Pseudo-velocity Spectrum (PSVS) Method". The method is based on the energy balance concept that uses the equality of energy demand and energy capacity of the structure. First, nonlinear static analyses are performed for five, eight and ten-story RC frame structures and pushover curves are obtained. Then the pushover curves are converted to energy capacity diagrams. Seven strong ground motions that were recorded at different soil sites in Turkey are used to obtain the pseudo-acceleration and the pseudo-velocity response spectra. Later, the response spectra are idealised with the Newmark-Hall approximation. Afterwards, energy demands for the RC structures are calculated using the idealised pseudo-velocity spectrum. The displacements, obtained from the energy capacity diagrams that fit to the energy demand values of the RC structures, are accepted as the energy-based performance point of the structures. Consequently, the target displacement values determined from the PSVS Method are checked using the displacement-based successive approach in the Turkish Seismic Design Code. The results show that the target displacements of RC frame structures obtained from the PSVS Method are very close to the values calculated by the approach given in the Turkish Seismic Design Code

Energy-based Design of Steel Structures According to the Predefined Interstory Drift Ratio

The methods which take place in current building codes and used in seismic design of structures are generally linear elastic. Inelastic behavior of the structures under the effect of earthquake is considered indirectly in seismic design codes. Recent studies enable inelastic behavior of structures to be taken into account properly in the structural design. In this study, a calculation method oriented towards the design of new structures which fulfill the predefined interstory drift ratio according to the usage function of the structures was offered by considering the inelastic behavior of the structural members and by using the energy balance of the structures. Interstory drift ratios when the steel structure displacements reach the target displacements were compared with the initial interstory drift ratios and the results were interpreted

Determination of earthquake safety of RC frame structures using an energy-based approach

An energy-based approach for determining earthquake safety of reinforced concrete frame structures is presented. The developed approach is based on comparison of plastic energy capacities of the structures with plastic energy demands obtained for selected earthquake records. Plastic energy capacities of the selected reinforced concrete frames are determined graphically by analyzing plastic hinge regions with the developed equations. Seven earthquake records are chosen to perform the nonlinear time history analyses. Earthquake plastic energy demands are determined from nonlinear time history analyses and hysteretic behavior of earthquakes is converted to monotonic behavior by using nonlinear moment-rotation relations of plastic hinges and plastic axial deformations in columns. Earthquake safety of selected reinforced concrete frames is assessed by using plastic energy capacity graphs and earthquake plastic energy demands. The plastic energy dissipation capacities of the frame structures are examined whether these capacities can withstand the plastic energy demands for selected earthquakes or not. The displacements correspond to the mean plastic energy demands are obtained quite close to the displacements determined by using the procedures given in different seismic design codes

Determination of lateral strength and ductility characteristics of existing mid-rise RC buildings in Turkey

This paper presents a comprehensive work on determination of yield base shear coefficient and displacement ductility factor of three to eight story actual reinforced concrete buildings, instead of using generic frames. The building data is provided by a walkdown survey in different locations of the pilot areas. Very detailed three dimensional models of the selected buildings are generated by using the data provided in architectural and reinforcement projects. Capacity curves of the buildings are obtained from nonlinear static pushover analyses and each capacity curve is approximated with a bilinear curve. Characteristic points of capacity curve, the yield base shear capacity, the yield displacement and the ultimate displacement capacity, are determined. The calculated values of the yield base shear coefficients and the displacement ductility factors for directions into consideration are compared by those expected values given in different versions of Turkish Seismic Design Code. Although having sufficient lateral strength capacities, the deformation capacities of these typical mid-rise reinforced concrete buildings are found to be considerably low

Landuse change detection in a surface coal mine area using multi-temporal high-resolution satellite images

Surface mining activities, exploitation of ore, and stripping and dumping of the overburden cause changes in the land cover and land use of a mine area. The area of land disturbance can be very large in the case of surface coal mining, due to the nature of the coal extraction process. Sustainable mining requires continuous monitoring of changes in land cover and land use induced by the mining activities. This is essentially important for identifying the long-term impacts of mining on the environment and on land cover in order to provide necessary mine closure and reclamation measures. In this sense, digital image classification provides a powerful tool for obtaining rigorous data, and reduces the cost of field measurements in time and money, particularly when dealing with large areas. Various remote sense data records and image classification techniques serve different features for numerous purposes. The selection of a suitable data and image classification method is significant for ensuring the effective use of information extracted from the satellite images, e.g. land-use classes. This paper proposes a methodology for identifying land-use change in surface coal mines using multi-temporal high-resolution satellite images. The methodology has been implemented for identifying, quantifying and analysing the spatial response of landscape to surface mining activities in the Goynuk, Bolu surface mine in Turkey, from 2004 to 2008. The methodology essentially entails (i) acquiring data, (ii) preprocessing the data, (iii) image classification using the maximum likelihood classification algorithm (iv) accuracy assessment and (v) change detection analysis depending on class-based approaches. The results show that the methodology can be utilised effectively in monitoring land-use change in surface coal mining areas. It also provides essential input for planning mine reclamation and closure activities

The effect of morphine delta receptor activity on ischemic postconditioning in lung ischemia reperfusion injury

OBJECTIVE: In the context of the physiopathology of lung damage due to ischemia and reperfusion injury, we aimed to reveal the effects of the addition of morphine sulfate to ischemic postconditioning (PC) protocol. METHODS: In the present study, 48 Wistar albino female rats were employed. Group 1 was accepted as the Sham group that underwent thoracotomy through the fifth left intercostal space. Ischemia-reperfusion (IR) group: Thoracotomy and IR period. IRPC group: thoracotomy, IR period and ischemic PC. In IRPC3 and IRPC30 groups, in addition to ischemic PC different doses of morphine sulfate (3 μmol and 30 μmol) was administered. Tumor necrosis factor (TNF)-α, interleukin (IL)-1, and IL-10 levels were measured in the biochemical assessment of the lung tissue samples obtained. RESULTS: TNF-α and IL-1 (pro-inflammatory cytokines) have lower values, and IL-10 (anti-inflammatory cytokine) have higher values both in the groups which have been subject to PC and morphine. TNF-α and IL-1 levels in lung tissue were statistically significant between the IRPC3 group and the IR and IRPC groups. In addition, IL-10 level in lung tissue was statistically significant between the IRPC3 group and the IRPC group. CONCLUSION: In the present study conducted with experimental animals where morphine was also injected beside ischemic PC protocols, statistically significant differences were determined in the lung tissue analyses when we compared pro-inflammatory and anti-inflammatory cytokine values. We firmly believe that adding morphine to the lung transplantation protocols and PC will decrease IR damage

Aggregometry Response to Half-dose Prasugrel in Flow-diverting Stent Implantation

Gok, Mustafa/0000-0001-7021-0984WOS: 000566420700006PubMed: 31165176Purpose the aim of this study was to determine whether half-dose loading (30/mg) of prasugrel is sufficient to achieve adequate platelet inhibition, and whether such a loading dose of prasugrel together with aspirin followed by a 10/mg/day prasugrel maintenance, could serve as a first-line antiplatelet strategy for patients undergoing flow-diverting stent (FDS) implantation. Methods Data from a group of consecutive patients treated for intracranial aneurysm with FDS were retrospectively collected. Platelet P2Y12 receptor responsiveness was assessed by a rapid platelet function test just prior to the procedure. All ischemic and hemorrhagic complications as well as morbidity and mortality rates were documented. Results A total of 138 patients with 153 aneurysms (32 were symptomatic and 121 were incidental) underwent FDS treatment in a total of 147 loading sessions. Adequate platelet inhibition was obtained in 136/138 (98.5%) patients and 145/147 (98.6%) loading sessions. Overall, there was one case of (hemorrhagic) mortality (0.7%), one of (ischemic) morbidity (0.7%), one of symptomatic (hemorrhagic) clinical complications without permanent deficits (0.7%), and six transient ischemic attacks (4.1%). the 6-month control angiography, available for all patients, revealed a 95.4% aneurysm occlusion rate. Conclusion Half-dose (30/mg) prasugrel loading results in effective platelet P2Y12 receptor inhibition in more than 98% of patients. Dual antiaggregant loading with half dose prasugrel followed by prasugrel maintenance as a first-line therapy appears to be feasible in patients treated with FDS implantation for intracranial aneurysm

A Bioinformatic Approach for the Identification of Molecular Determinants of Resistance/Sensitivity to Cancer Thermotherapy.

Application of heat above 43 degrees C and up to 47 degrees C, the so-called "thermal ablation" range, leads to tumor cell destruction either by apoptosis or by necrosis. However, tumor cells have developed mechanisms of defense that render them thermoresistant. Of importance, the in situ application of heat for the treatment of localized solid tumors can also prime specific antitumor immunity. Herein, a bioinformatic approach was employed for the identification of molecular determinants implicated in thermoresistance and immunogenic cell death (ICD). To this end, both literature-derived (text mining) and microarray gene expression profile data were processed, followed by functional enrichment analysis. Two important functional gene modules were detected in hyperthermia resistance and ICD, the former including members of the heat shock protein (HSP) family of molecular chaperones and the latter including immune-related molecules, respectively. Of note, the molecules HSP90AA1 and HSPA4 were found common between thermoresistance and damage signaling molecules (damage-associated molecular patterns (DAMPs)) and ICD. In addition, the prognostic potential of HSP90AA1 and HSPA4 overexpression for cancer patients' overall survival was investigated. The results of this study could constitute the basis for the strategic development of more efficient and personalized therapeutic strategies against cancer by means of thermotherapy, by taking into consideration the genetic profile of each patient