The structural analysis of a 95-year-old concrete arch bridge located in Jagodnik (Poland) is performed in this paper, in order to check its behavior under today's traffic loads. The mechanical ...properties of both the concrete and the reinforcement are investigated by testing cores and bar stubs extracted from the bridge. Structural analysis confirms that the bridge meets today's load requirements in terms of bearing capacity, serviceability state, and that the adopted structural improvements (a new deck slab on top of the existing structure and a layer of mortar to protect the surface of the old concrete) are effective. In this way, the 95-year-old arch bridge was given a new life. The structural improvements show how combining numerical modelling and laboratory tests can contribute to the preservation of an old-though fairly simple-and valuable structure, otherwise destined to demolition, with both environmental and economic benefits.
The structural analysis of an old steel riveted railway truss bridge located over the Maruska River on the Działdowo – Olsztyn, Poland railway line is performed in this paper to check its behaviour ...under today’s railway loads. The mechanical properties of construction steel extracted from the old steel bridge are investigated by tensile tests, impact tests through the Charpy pendulum impact V-notch, and an optical emission spectrometer. Structural analysis exhibits that the steel bridge requires proper structural bridge improvements to meet today’s load requirements in terms of bearing capacity and serviceability state. The paper begins with a wide survey of literature carried out on the investigation of steel riveted railway bridge subject matter. This paper can provide scientists, engineers, and designers with an experimental and structural basis in the field of old steel riveted railway truss bridge construction.
Background
Transarterial chemoembolization (TACE) is an important therapy for hepatocellular carcinoma (HCC) in cirrhosis. In particular in advanced cirrhosis, post-TACE hepatic failure liver (PTHF) ...failure may develop. Currently, there is no standardization for the periinterventional risk assessment. The liver maximum capacity (LiMAx) test assesses the functional liver capacity, but has not been investigated in this setting.
Aims
The aim of this study was to prospectively evaluate periinterventional LiMAx and CT volumetry measurements in patients with cirrhosis and HCC undergoing repetitive TACE.
Methods
From 06/2016 to 11/2017, eleven patients with HCC and cirrhosis undergoing TACE were included. LiMAx measurements (
n
= 42) were conducted before and after each TACE. Laboratory parameters were correlated with the volume–function data.
Results
The median LiMAx levels before (276 ± 166 µg/kg/h) were slightly reduced after TACE (251 ± 122 µg/kg/h;
p
= 0.08). This corresponded to a median drop of 7.1%. Notably, there was a significant correlation between LiMAx levels before TACE and bilirubin (but not albumin nor albumin–bilirubin ALBI score) increase after TACE (
p
= 0.02,
k
= 0.56). Furthermore, a significantly higher increase in bilirubin in patients with LiMAx ≤ 150 µg/kg/h was observed (
p
= 0.011). LiMAx levels at different time points in single patients were similar (
p
= 0.2).
Conclusion
In our prospective pilot study in patients with HCC and cirrhosis undergoing multiple TACE, robust and reliable LiMAx measurements were demonstrated. Lower LiMAx levels before TACE were associated with surrogate markers (bilirubin) of liver failure after TACE. Specific subgroups at high risk of PTHF should be investigated. This might facilitate the future development of strategies to prevent occurrence of PTHF.
The structural analysis of a road foldable prefabricated steel Bailey- type bridge located over the Tuga River in Żelichowo, Poland is performed in this paper. Interesting and untypical bridge ...redevelopment performed made it possible to lift the middle foldable bridge span by approximately 4.0 m concerning the existing state. The paper begins with a survey of literature carried out on the investigations of foldable Bailey-type bridge subject matter. A description of the numerical modelling of foldable prefabricated bridges is performed. The comparison of the proof load test results with the FEM numerical model results has shown very good compatibility. This paper can provide scientists, engineers, and designers the basis for structural analysis in the field of foldable Bailey-type bridge constructions and numerical simulations.
Glycoporphyrins are group of compounds of high value for the purpose of photodynamic therapy and other biomedical applications. Despite great progress in the field, new diversity-oriented syntheses ...of carbohydrate-porphyrin hybrids are increasingly desired. Herein, we present efficient, mild, and metal-free conditions for synthesis of glycoporphyrins. The versatile nature of the SNAr procedure is presented in 16 examples. Preliminary biological studies have been conducted on the cytotoxicity and cellular uptake of the final molecules.
Objectives
To evaluate changes in liver function after right portal vein embolization (PVE) and extended right hemihepatectomy using gadolinium ethoxybenzyl-DTPA-enhanced (Gd-EOB-DTPA) MRI.
Methods
...In this prospective trial, 37 patients undergoing PVE were examined before and 14 and 28 days after PVE and 10 days after extended hemihepatectomy using Gd-EOB-DTPA-enhanced MRI. Lobar volume, kinetic growth rate (KGR), relative enhancement (RE) as well as hepatocellular uptake index (HUI) and fat signal fraction (FSF) were calculated for each lobe.
Results
RE of the left liver lobe (LLL) was steadily increasing after PVE and decreased to 0.48 ± 0.19 10 days after surgery, which is significantly lower than 14 days and 28 days post PVE (
P
< 0.05). KGR was 14.06 ± 9.82%/week for the period from PVE to 14 days after PVE. HUI of the LLL increased steadily after PVE and was significantly higher at both 14 and 28 days after PVE compared to pre PVE (
P
< 0.05). HUI of the residual liver after surgery was lower than before.
Conclusions
Gd-EOB-DTPA-enhanced MRI may be used to monitor the functional increase in the FLR after PVE and to depict the intraoperative liver injury leading to a decrease in liver remnant function.
Key Points
• The most significant FLR volume increase happens within the first 14 days.
• No MRI parameter was able to predict the success of FLR growth.
• Our data suggest an early resection about 14 days after PVE.
• Routine Gd-EOB-DTPA-enhanced MRI might be suitable to replace ICG-test.
Surgical procedures in patients with underlying liver disease are still burdened by a high rate of postoperative morbidity, especially posthepatectomy liver failure (PHLF), ranging from 1.2 to 33.8%. ...The aim of this study was to investigate the prognostic value of volume/function analysis for the prediction of hepatectomy-related morbidity in patients with hepatocellular carcinoma.
Clinicopathological data were analysed in 261 patients who underwent liver resection for HCC between 2001 and 2014. Future liver remnant volume (FLRV) and future liver remnant function (FLRF) based on LiMAx test were obtained retrospectively. A subgroup analysis for high-risk patients with impaired liver function was conducted. Univariate and multivariate regression analysis was performed to identify risk factors for major complications, defined by Dindo ≥ IIIb and PHLF grade ≥ B.
In the total cohort, FLRF was independently associated with major complications. FLRV, resected liver volume, and FLRF were independent risk factors for PHLF. In a subgroup analysis of high-risk patients, FLRF was identified as the only independent risk factor for major complications and PHLF development.
These results suggest the superior value of FLRF to FLRV in predicting postoperative complications as well as PHLF in patients with chronic liver disease.
Background
Chemotherapy of colorectal liver metastases (CLMs) prior to liver resection implies the risk of chemotherapy-associated liver injury, leading to increased postoperative morbidity and ...mortality
Objective
The aim of this study was to evaluate the LiMAx (liver maximum capacity) test for diagnosis of chemotherapy-associated liver injury.
Methods
This was a retrospective analysis of patients with CLMs, prior to liver resection. We performed preoperative assessment of liver function using biochemical parameters and the LiMAx test. The individual history of chemotherapy within 12 months, including regimen, number of cycles, and therapy-free interval were collected, and histopathological evaluation of tumor-free liver tissue was performed in resected patients.
Results
A total of 204 patients were included, of whom 127 (62%) had received previous chemotherapy. The LiMAx test was worse after chemotherapy (340 ± 95 vs. 391 ± 82 µg/kg/h;
p
<
0.001). Impaired LiMAx results (<315 µg/kg/h) were determined in 49% of patients after chemotherapy, and no effects of chemotherapy, liver steatosis or fibrosis on biochemical parameters were observed. LiMAx impairment was dependent on the number of oxaliplatin cycles, the therapy-free interval, and obesity in multivariate analysis. In addition, the LiMAx test was worse in patients with relevant steatosis, fibrosis and steatohepatitis. Patients with an impaired LiMAx showed sufficient regeneration during chemotherapy cessation when surgery was postponed (272 ± 57 – 348 ± 72 µg/kg/h;
p
=
0.003).
Conclusion
The LiMAx test enables non-invasive preoperative diagnosis of chemotherapy-associated liver injury. Preoperative performance of the LiMAx test can augment surgical strategy and timing of surgery after previous chemotherapy, thus avoiding increased postoperative morbidity.
The hypoxia-inducible transcription factor HIF-1 is appreciated as a promising target for cancer therapy. However, conditional deletion of HIF-1 and HIF-1 target genes in cells of the tumor ...microenvironment can result in accelerated tumor growth, calling for a detailed characterization of the cellular context to fully comprehend HIF-1's role in tumorigenesis. We dissected cell type-specific functions of HIF-1 for intestinal tumorigenesis by lineage-restricted deletion of the Hif1a locus. Intestinal epithelial cell-specific Hif1a loss reduced activation of Wnt/β-catenin, tumor-specific metabolism and inflammation, significantly inhibiting tumor growth. Deletion of Hif1a in myeloid cells reduced the expression of fibroblast-activating factors in tumor-associated macrophages resulting in decreased abundance of tumor-associated fibroblasts (TAF) and robustly reduced tumor formation. Interestingly, hypoxia was detectable only sparsely and without spatial association with HIF-1α, arguing for an importance of hypoxia-independent, i.e., non-canonical, HIF-1 stabilization for intestinal tumorigenesis that has not been previously appreciated. This adds a further layer of complexity to the regulation of HIF-1 and suggests that hypoxia and HIF-1α stabilization can be uncoupled in cancer. Collectively, our data show that HIF-1 is a pivotal pro-tumorigenic factor for intestinal tumor formation, controlling key oncogenic programs in both the epithelial tumor compartment and the tumor microenvironment.
Background
Postoperative bile leakage (PBL) is a major surgical complication after partial liver resection resulting in increased perioperative morbidity and mortality. Previous experimental studies ...have shown an adverse effect on functional liver regeneration, but there are still no data available concerning these effects in humans.
Materials and methods
A retrospective matched pair analysis was carried out comparing the postoperative course of 51 patients with PBL to 51 patients without PBL. The influence of PBL on actual liver function was determined by means of LiMAx, Indocyanine green plasma disappearance rate (ICG-PDR), and standard liver function tests.
Results
The analyzed groups were matched regarding demographic, preoperative, and operative data. Bilirubin, ICG-PDR and LiMAx showed delayed postoperative functional recovery after partial liver resection in the PBL group compared to the non-PBL group. LiMAx was the single parameter to assess differing liver regeneration continuously from the 3rd to 14th postoperative day between the groups. A subanalysis revealed an early recovery from impaired functional regeneration if the bile leakage was diagnosed until the 5th postoperative day (POD) or successfully treated until the 14th POD.
Conclusion
These are the first data evaluating the impact of PBL on functional regeneration after liver surgery. Liver regeneration after partial liver resection is impaired by PBL. However, a nearly normal recovery is possible if the bile leak is diagnosed early and immediately treated. Moreover, patients presenting with delayed functional recovery in the postoperative course are likely to have complications, e.g., bile leakage.
PDF
