Outcomes of Combined Liver-Kidney Transplantation - Single Center Experience.

BACKGROUND: There is continuous growth of combined liver-kidney transplantation (CLKTx) numbers with remarkable outcomes, especially among patient with liver cirrhosis and end-stage renal disease. The aim was to present a single center experience. METHODS: Twenty patients (9 males) with a mean age of 48 (range: 20-62) years underwent CLKTx from 2005 to 2022. Indications were polycystic liver and kidney diseases (ADPKD) in 12 cases, cirrhosis due to hepatitis (4 patients), and 1 case of amyloidosis, alcoholic liver disease, nonalcoholic steatosis, and congenital hepatic fibrosis with concomitant glomerulonephritis. After hepatectomy, half of the patients had orthotopic liver transplantation with piggy-back technique, and the other had conventional technique. All but 1 recipient had biliary end-to-end anastomosis. 3 patients had preemptive kidney graft transplantation. 4 underwent simultaneous right-side nephrectomy due to volume of the right kidney. Kidney was transplanted from the separate incision after abdominal closure with typical anastomoses. Tacrolimus, mycophenolate mofetile, basiliximab, and steroids were applied for all recipients. RESULTS: Mean follow-up was 57.7 ± 54 months. No primary non-function of the grafts occurred. Delayed kidney graft function (DGF) occurred in 8 patients. Three-month, 1-year, and 5-year cumulative survival rates were: 90%, 80%, and 72% respectively. None of the patients required retransplantation, and 1 recipient returned to hemodialysis 19 months after transplantation. Preemptive kidney transplantation and simultaneous right-side nephrectomy were not significant for DGF and recipient survival. No deaths within the first year occurred in piggy-back technique. CONCLUSIONS: CLKTx is safe and effective in the treatment of both liver and kidney failure.

Synthesis of graphite-based lead composites and modification of their physicochemical and electrochemical properties.

The present work describes preparation of a graphite lead composite, its modification and the examination of basic physicochemical and electrochemical properties. Graphite lead composites are the products of reaction of lead chloride with flaky graphite performed in a molten salt system. The process was carried out at 450 °C for 96 hours. In the second stage, the obtained composites were subjected to thermal or chemical treatment in order to modify their physicochemical properties. The structure of the as prepared material has been examined by X-ray diffraction analysis. Transmission electron microscopy analysis (TEM) along with energy dispersive spectroscopy (EDS) have been used to determine the size as well as the distribution of Pb particles. To study the electrochemical properties of graphite-based lead composites, cyclic voltammetry and galvanostatic methods have been used. It has been proved that the thermally modified compound at 600 °C contains on its surface spherical particles of lead chloride and/or oxide with diameters varying from hundreds of nanometers to several micrometers. The acquired electrochemical results revealed that graphite/Pb composites exhibit good electrochemical activity towards the reversible reaction of Pb → Pb2+ oxidation. Charge associated with the reversible transformation of Pb to Pb2+ amounts to 15.72 C g-1 and 14.62 C g-1 for the original compound and the compound heated at 600 °C, respectively. It has been also proved that the highest level of structure modification of the composite is reached by its chemical treatment with hydrogen peroxide. However, the mentioned modification leads to the removal of the entire lead from the structure of the graphite matrix.

Effects of various rotational speeds of hydrodynamic disintegrator on carbon, nutrient, and energy recovery from sewage sludge.

Until recently, sewage sludge produced in wastewater treatment processes was considered problematic waste. It currently constitutes a valuable substrate for raw materials and energy recovery. One of the methods of intensifying resource recovery from sludge is its pretreatment by means of disintegration methods. This study presents the CFD modelling and experimentally investigates the use of a hydrodynamic cavitation rotor operated with various rotational speeds (1500, 2500, and 300 rpm) for the recovery of organic compounds, nutrients, and energy. Rheological properties of raw sludge, a non-Newtonian fluid, were determined and used in the modelling calculations. Cavitation zones were observed for 2500 rpm and 3000 rpm, although a stronger cavitation effect occurred for a rotational speed of 3000 rpm. A rotational speed of 1500 rpm was too low to generate a pressure drop below 1705 Pa, and no cavitation was recorded. An increase in rotational speed from 1500 rpm to 3000 rpm for each analysed energy density caused an increase in SCOD and nitrogen concentration. Moreover, it was determined that at low energy densities (<105 kJ/L), mechanical tearing was the dominant factor responsible for carbon recovery, and at its higher values (≥105 kJ/L), the cavitation phenomenon became increasingly important. Rotation speed also had a significant effect on methane yield (YCH4). An increase in YCH4 by 6.2% was recorded only for disintegrated sludge at a rotational speed of 1500 rpm in reference to untreated sludge. Disintegration conducted at higher rotational speeds led to a decrease in YCH4 (-0.7% for 2500 rpm and -7.9% for 3000 rpm).

Re-flocculation reduces the effectiveness of sewage sludge pretreatment through hydrodynamic disintegration prior to anaerobic digestion.

Circular economy model, based on the "make, use, reuse, remake, recycle" approach, is an alternative to progressive depletion of non-renewable fossil fuels. Sewage sludge can be a source of renewable energy obtained through the anaerobic conversion of their organic fraction into biogas. This process is mediated by highly complex microbial communities and its efficiency depends on the availability of substrates to microorganisms. Disintegration of the feedstock in the pre-treatment step may intensify the anaerobic digestion, but re-flocculation of disintegrated sludge (reassembly of the released fractions into larger agglomerates) may result in a reduced availability of the released organic compounds for microbes. Pilot-scale studies on re-flocculation of disintegrated sludge were conducted to select parameters for scaling-up the pre-treatment and intensifying the anaerobic digestion process in two large Polish wastewater treatment plants (WWTPs). Samples of thickened excess sludge from full-scale WWTPs were subjected to hydrodynamic disintegration at three energy density levels of 10 kJ/L, 35 kJ/L and 70 kJ/L. Microscopic analyses of disintegrated sludge samples were carried out twice: i) immediately after the disintegration process at a given energy density level, ii) and after 24-h incubation at 4 °C following the disintegration. Micro-photographs of 30 randomly selected fields of view were taken for each analysed sample. A method of the image analysis was developed as a tool to measure dispersion of sludge flocs to assess the re-flocculation degree. Re-flocculation of the thickened excess sludge occurred within 24 h after hydrodynamic disintegration. This was evidenced by a very high re-flocculation degree, reaching up to 86%, depending on the origin of the sludge and the energy density levels used for the hydrodynamic disintegration.

Lymphangioma Cavernosum with a Rare Location.

Lympangioma cavernosum in the abdominal cavity is a rare benign tumour. In most cases, such tumours are diagnosed in the oral cavity and neck. The aim of this paper is to present our clinical observations and review of existing literature to draw attention to this disease. A 25-year-old woman was admitted to our department for a symptomatic tumour in the lesser curvature of the stomach. The patient was first operated on as a three-year-old child because the tumour extended from the back wall of the stomach to the gastro-colonic ligament. The medical records showed that it was a benign tumour; however, no diagnosis was specified. No symptoms were observed for 22 years. Currently, the patient is admitted for epigastric pain. Abdominal computed tomography revealed an extensive mass located between the left segments of the liver and the lesser curvature of the stomach. The patient was operated on, and the tumour was completely removed. The patient's postoperative course was uneventful. Histopathological examination of the lymphangioma cavernosum was performed. Two months after the operation, the patient did not report any complaints.

DRD4 Exon 3 Gene Polymorphisms in Patients Diagnosed with Polysubstance Use Disorder and Co-Occurrence of a Depressive Episode.

BACKGROUND: There has been a noticeable and systematic growth of the use of psychoactive substances over the past few decades. Dual diagnosis is a clinical term referring to the occurrence of psychoactive substance use disorder comorbid with another psychiatric disorder in the same person. The most common type of dual diagnosis is the co-occurrence of alcohol use disorder and mood disorders in the form of a depressive episode. Co-occurrent substance use disorders are frequently influenced by genetic factors. In selecting our area of research, we focused on dopamine and the DRD4 (Dopamine Receptor D4) gene polymorphism as well as associations with personality features. THE AIM OF THE STUDY: The aim of the study was to compare DRD4 exon 3 (DRD4 Ex3) gene polymorphisms in patients diagnosed with polysubstance use disorder and co-occurrence of a depressive episode to DRD4 exon 3 gene polymorphisms in patients diagnosed with polysubstance use disorder and without co-occurrence of a depressive episode and a group of healthy volunteers. The study also aimed at establishing associations between personality features and DRD4 exon 3 gene polymorphisms of male patients diagnosed with polysubstance use disorder with co-occurrence of a depressive episode which may present a specific endophenotype of this group of patients. METHODS: The study group comprised 602 male volunteers: patients diagnosed with polysubstance use disorder comorbid with a depressive episode (PUD MDD) (n = 95; mean age = 28.29, standard deviation (SD) = 7.40), patients diagnosed with polysubstance use disorder (PUD) (n = 206; mean age = 28.13, SD = 5.97), and controls (n = 301; mean age = 22.13, SD = 4.57). The patients and control subjects were diagnosed by a psychiatrist using the Mini International Neuropsychiatric Interview (MINI), the NEO Five-Factor Personality Inventory (NEO-FFI), and the State-Trait Anxiety Inventory (STAI) questionnaires. An analysis of the DRD4 exon 3 polymorphism was performed. RESULTS: The patients diagnosed with PUD MDD compared to the control group of healthy volunteers showed significantly higher scores on both the STAI status and features scale and the NEO-FFI Neuroticism and Openness Scale, as well as lower scores on the Extraversion, Agreeableness, and Conscientiousness NEO-FFI scales. In the DRD4 exon 3 gene polymorphism, the s allele was more frequent in the PUD MDD compared to the l allele, which was less frequent. The results of the 2 × 3 factor analysis of variance (ANOVA) in patients and controls and the variant DRD4 exon 3 interaction were found on the Extraversion Scale and the Conscientiousness Scale of the NEO-FFI. CONCLUSIONS: The associations show that psychological factors combined with genetic data create a new area of research on addiction, including the problem of dual diagnosis. However, we want to be careful and draw no definite conclusions at this stage of our research.

Skin autofluorescence as a novel predictor of acute kidney injury after liver resection.

BACKGROUND: Skin autofluorescence (SAF) reflects accumulation of advanced glycation end-products (AGEs). The aim of this study was to evaluate predictive usefulness of SAF measurement in prediction of acute kidney injury (AKI) after liver resection. METHODS: This prospective observational study included 130 patients undergoing liver resection. The primary outcome measure was AKI. SAF was measured preoperatively and expressed in arbitrary units (AU). RESULTS: AKI was observed in 32 of 130 patients (24.6%). SAF independently predicted AKI (p = 0.047), along with extent of resection (p = 0.019) and operative time (p = 0.046). Optimal cut-off for SAF in prediction of AKI was 2.7 AU (area under the curve [AUC] 0.611), with AKI rates of 38.7% and 20.2% in patients with high and low SAF, respectively (p = 0.037). Score based on 3 independent predictors (SAF, extent of resection, and operative time) well stratified the risk of AKI (AUC 0.756), with positive and negative predictive values of 59.3% and 84.0%, respectively. In particular, SAF predicted AKI in patients undergoing major and prolonged resections (p = 0.010, AUC 0.733) with positive and negative predictive values of 81.8%, and 62.5%, respectively. CONCLUSIONS: AGEs accumulation negatively affects renal function in patients undergoing liver resection. SAF measurement may be used to predict AKI after liver resection, particularly in high-risk patients.

Incisional Surgical Site Infections After Mass and Layered Closure of Upper Abdominal Transverse Incisions: First Results of a Randomized Controlled Trial.

OBJECTIVE: To compare the early results of mass and layered closure of upper abdominal transverse incisions. SUMMARY OF BACKGROUND DATA: Contrary to midline incisions, data on closure of transverse abdominal incisions are lacking. METHODS: This is the first analysis of a randomized controlled trial primarily designed to compare mass with layered closure of transverse incisions with respect to incisional hernias. Patients undergoing laparotomy through upper abdominal transverse incisions were randomized to either mass or layered closure with continuous sutures. Incisional surgical site infection (incisional-SSI) was the primary end-point. Secondary end-points comprised suture-to-wound length ratio (SWLR), closure duration, and fascial dehiscence (clinicatrials.gov NCT03561727). RESULTS: A total of 268 patients were randomized to either mass (n=134) or layered (n=134) closure. Incisional-SSIs occurred in 24 (17.9%) and 8 (6.0%) patients after mass and layered closure, respectively (P =0.004), with crude odds ratio (OR) of 0.29 [95% confidence interval (95% CI) 0.13-0.67; P =0.004]. Layered technique was independently associated with fewer incisional-SSIs (OR: 0.29; 95% CI 0.12-0.69; P =0.005). The number needed to treat, absolute, and relative risk reduction for layered technique in reducing incisional-SSIs were 8.4 patients, 11.9%, and 66.5%, respectively. Dehiscence occurred in one (0.8%) patient after layered closure and in two (1.5%) patients after mass closure (P >0.999). Median SWLR were 8.1 and 5.6 (P <0.001) with median closure times of 27.5 and 25.0 minutes (P =0.044) for layered and mass closures, respectively. CONCLUSIONS: Layered closure of upper abdominal transverse incisions should be preferred due to lower risk of incisional-SSIs and higher SWLR, despite clinically irrelevant longer duration.

Long-Term Effects of Pedicle Clamping during Major Hepatectomy for Colorectal Liver Metastases.

The use of the Pringle maneuver (PM) varies widely among surgical departments. Its use depends on the operator and type of liver resection. The aim of this study was to determine the impact of the PM on patient outcomes when undergoing major liver resections. This retrospective study comprised 179 colorectal liver metastasis patients from two liver centers from Leeds and Warsaw. Only right or right extended hepatectomies with negative oncological margins were included. The primary outcome measure was the 5-year overall survival (OS). The PM was applied during 60 (33.5%) major hepatectomies included in the study and was associated with a higher peak 3-day postoperative bilirubin concentration (p = 0.002), yet not with the peak 3-day alanine aminotransferase activity (p = 0.415). The 5-year OS after liver resections with the PM and without the PM were 55.0% and 33.4%, respectively (p = 0.019). Following stratification by the Tumor Burden Score, after resections with the use of the PM, superior survival was particularly found in the subgroup of patients at intermediate risk of recurrence (p = 0.004). However, the use of the PM had no significant effect on the 5-year overall survival following adjustment for the confounding effect of the carcinoembryonic antigen concentration (p = 0.265). The use of the PM had no negative effects on the long-term outcomes in patients undergoing major, oncologically radical liver resections for colorectal metastases.

PEComa-A Rare Liver Tumor.

PEComa (perivascular epithelioid cell tumor) is a rare liver tumor. Decisions regarding patient management are currently based on a few small case series. The aim of this study was to report the clinicopathological features of PEComa in order to provide guidance for management, complemented by our own experience. This retrospective observational study included all patients with PEComa who underwent surgical treatment in two departments between 2002 and 2020. A total of 20 patients were diagnosed with PEComa following histopathological examination. The age of the patients ranged from 21 to 73 years. The majority of patients were women (85%). In most patients, the tumors were incidental. In diagnostic studies, PEComas with high arterial vascularization have been described. Liver resection was the treatment of choice. There was only one postoperative complication. During histopathological evaluation, tumors were composed mostly of epithelioid cells, rarely with spindle cell components, thick-walled vessels, and adipocytes in different proportions. Melanocytic markers (HMB45, MelanA) and at least one smooth muscle marker were expressed in all tumors. Features suggestive of malignancy were found in three cases. In conclusion, PEComa is a rare liver tumor that is usually diagnosed incidentally. In radiological studies, tumors with high arterial vascularization are observed. Liver resection is the treatment of choice.

An assessment of physical efficiency in cadet pilots before and after the implementation of a program preparing for flights.

OBJECTIVES: The aim of the study was to examine the impact of the training program on directed physical fitness. MATERIAL AND METHODS: The research involved 35 male cadets of the Polish Air Force Academy in Deblin. The examined persons were on average 19 years old. All the examined persons were divided into 2 groups. Group I (N = 25, the test group) carried out a program on Special Aviation Gymnastic Instruments. Group II (N = 10, the control group) conducted the standard physical military education program. In both groups, the test was performed twice, before (examination I) and after (examination II) the preparatory process, using the following tests: pull-ups, a 16.5-meter race, a 10×10-meter shuttle race, forward bends, and the Aviation Synthetic Efficiency Test (ASET). The findings obtained in these tests were converted into points for the overall evaluation of physical fitness. The training lasted 70 days. RESULTS: In group I, in examination II, there was a statistically significant increase in the results of pull-ups (p < 0.01), the 16.5-meter race (p < 0.01), the 10×10-meter shuttle race (p < 0.05), forward bends for 2 min (p < 0.05) and the overall physical fitness (p < 0.05), compared to examination I. In group II, in examination II, the authors proved an insignificant increase in the findings when contrasted with examination I. The test results between groups I and II did not show any significant differences in the examined efficiency tests. In group I, in examination I, significant correlations were found between the overall physical fitness and pull-ups, the 10×10-meter shuttle race, the 16.5-meter race, forward bends and ASET. Examination II demonstrated significantly stronger correlations between the overall physical fitness and forward bends as well as ASET. In group II, in examination II, a significant correlation was shown between the overall physical fitness and the 16.5-meter race. CONCLUSIONS: A significant correlation between the overall physical fitness and ASET in examination II indicates an impact of the training program on the targeted efficiency of the cadet pilots. Int J Occup Med Environ Health. 2021;34(5):647-58.

Intraductal papillary neoplasm of the bile duct - A comprehensive review.

BACKGROUND: Intraductal papillary neoplasm of the bile ducts is a rare tumor type. Management decisions are currently based upon a small case series. The authors have large own experience with IPNB. OBJECTIVE: The review aims at reporting on clinicopathological features of IPNB in order to provide guidance for management. METHODS: We searched PubMed, Medline, Microsoft Academic and Embase databases to identify studies of relevance. The analysis of own experience was also included. RESULTS: We analyzed 59 retrospective series and 25 cases from authors' clinical experience. The main sign was jaundice and cholangitis, 33% and 48%, respectively. CT's were performed in 63-76% and MR in 40-56%. Intraductal mass was found in 31-32% and duct dilatation in 27-30%. Endoscopic Retrograde Cholangio-Pancreatography (ERCP) was performed in 48-62%. IPNB with invasive carcinoma was found in 35.7-60% and IPNB with intraepithelial neoplasia in 36-60%. Histopathological confirmation before surgery was rare. The main treatment of IPNB is resection, in our material, both, hepatectomy and hepatectomy plus bile duct resections were performed in 40% of patients. The percentage of postoperative complications was 20%. The 5-year survival rate of all IPNB's patients was 53.6%; in patients with associated invasive carcinoma - 22.2% and without invasive carcinoma - 100% (p â€‹= â€‹0.001). CONCLUSIONS: Early surgery is advisable for radiologically suspected IPNB. The results of treatment depend on histopathology. They are worse at intraductal invasive carcinoma than at neoplasm with neoplasia.

Common ALDH3A1 Gene Variant Associated with Keratoconus Risk in the Polish Population.

BACKGROUND: ALDH3A1 protein is important in maintaining corneal physiology and protecting the eye from UV damage. However, none of the genome-wide association studies has indicated that the ALDH3A1 locus is associated with keratoconus. In this study, we examined the potential role of ALDH3A1 variants as risk factors for keratoconus incidence and severity in a large group of Polish keratoconus patients. METHODS: In the first stage we analyzed the coding region sequence of the ALDH3A1 in a subgroup of keratoconus. Then, we genotyped three selected ALDH3A1 variants in a larger KC group of patients (n = 261) and healthy controls (n = 317). RESULTS: We found that the rs1042183 minor allele A is a risk factor for keratoconus in the dominant model (OR = 2.06, 95%CI = 1.42-2.98, p = 0.00013). The rs2228100 variant genotypes appear to be associated with an earlier age of KC diagnosis in the Polish population (p = 0.055 for comparison of three genotypes and p = 0.022 for the dominant inheritance model). CONCLUSIONS: The rs1042183 variant in ALDH3A1 is associated with keratoconus risk in the Polish population. The differences in the allele frequency between both populations could be partially responsible for the difference in the disease prevalence.

The assessment of the impact of a training process on the habituation of the vestibular-vegetative system, using a special rotational test as a condition of maintaining flight safety.

OBJECTIVES: The authors formulated a hypothesis that, on completion of the training program by cadets, their vestibular habituation would increase, measured by the time of the duration of the test on the unlocked looping, in contrast to the initial values and the control group. MATERIAL AND METHODS: The research involved 35 male cadets, first-year students of the Polish Air Force Academy in Deblin. The examined persons were on average 20 years of age. They were divided into 2 groups. Group A (N = 25, tested) continued training on Special Aviation Gymnastic Instruments (SAGI). The cadets were a homogeneous group of participants in the jet pilot course, selected by the Military Aeromedical Board. Group B (N = 10, control) conducted the standard physical military education program. Groups A and B were tested on the unlocked looping before and after the training process. In the training process, the groups had heart rate (HR) monitored. RESULTS: The cadets in group A on the test in the unlocked looping, at the beginning of the training period, had an average score of 468.5±96.6 s, and on completion of the training period 575.6±47.9 s, which is a statistically significant difference at p < 0.000001. Similarly, the examined individuals in group B received an average score of 396.2±31.8 s, and at the end of the training period 473.4±72.0 s, which is a statistically significant difference at p < 0.01. In group A, a statistically significant decrease in the average HR value was observed. In group B, there was a statistically significant increase in the average HR value. CONCLUSIONS: The exercises on SAGI have a beneficial impact on improving the habituation of the vestibular organ in training cadets in examination II, as opposed to examination I and the control group. Int J Occup Med Environ Health. 2020;33(4):497-506.

ICD-11 vs. ICD-10 - a review of updates and novelties introduced in the latest version of the WHO International Classification of Diseases. / ICD-11 vs. ICD-10 ­ przeglad aktualizacji i nowosci wprowadzonych w najnowszej wersji Miedzynarodowej Klasyfikacji Chorób WHO.

In June 2018, WHO published the 11th edition of the International Classification of Diseases (ICD). The new edition introduced numerous changes. One of the most important was to rebuild the coding system and adapt ICD to digital use. A reconstruction of the coding system enabled more comprehensive alphanumeric coding of complex clinical situations by the introduction of cluster coding. The chapter on mental disorders has also changed. ICD-11 has been updated to take into account the results of international expert cooperation and new information on mental disorders. Many of the secondary clinical categories have been moved higher in the hierarchy that created new subchapters. Many categories have been moved to other subchapters. Taking into account the modern epidemiology and knowledge about the etiology of mental disorders, some categories have been removed from ICD. Moreover, several nonexistent categories have been added. The article summarizes and discusses the most important changes in ICD with the introduction of ICD-11, both in the coding system and in individual subchapters covering mental health issues.

Carbon Fiber and Nickel Coated Carbon Fiber-Silica Aerogel Nanocomposite as Low-Frequency Microwave Absorbing Materials.

Silica aerogel-based materials exhibit a great potential for application in many industrial applications due to their unique porous structure. In the framework of this study, carbon fiber and nickel coated carbon fiber-silica aerogel nanocomposites were proposed as effective electromagnetic shielding material. Herein, the initial oxidation of the surface of carbon fibers allowed the deposition of a durable Ni metallic nanolayer. The fibers prepared in this way were then introduced into a silica aerogel structure, which resulted in obtaining two nanocomposites that differed in terms of fiber volume content (10% and 15%). In addition, analogous systems containing fibers without a metallic nanolayer were studied. The conducted research indicated that carbon fibers with a Ni nanolayer present in the silica aerogel structure negatively affected the structural properties of the composite, but were characterized by two-times higher electrical conductivity of the composite. This was because the nickel nanolayer effectively blocked the binding of the fiber surface to the silica skeleton, which resulted in an increase of the density of the composite and a reduction in the specific surface area. The thermal stability of the material also deteriorated. Nevertheless, a very high electromagnetic radiation absorption capacity between 40 and 56 dB in the frequency range from 8 to 18 GHz was obtained.

Native Osseous CaP Biomineral Coating on a Biomimetic Multi-Spiked Connecting Scaffold Prototype for Cementless Resurfacing Arthroplasty Achieved by Combined Electrochemical Deposition.

The multi-spiked connecting scaffold (MSC-Scaffold) prototype with spikes mimicking the interdigitations of articular subchondral bone is an essential innovation in surgically initiated fixation of resurfacing arthroplasty (RA) endoprosthesis components. This paper aimed to present a determination of the suitable range of conditions for the calcium phosphate (CaP) potentiostatic electrochemical deposition (ECDV=const) on the MSC-Scaffold prototype spikes to achieve a biomineral coating with a native Ca/P ratio. The CaP ECDV=const process on the MSC-Scaffold Ti4Al6V pre-prototypes was investigated for potential VECDfrom -9 to -3 V, and followed by 48 h immersion in a simulated body fluid. An acid-alkaline pretreatment (AAT) was applied for a portion of the pre-prototypes. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) studies of deposited coatings together with coatings weight measurements were performed. Themost suitable VECD range, from -5.25 to -4.75 V, was determined as the native biomineral Ca/P ratio of coatings was achieved. AAT increases the weight of deposited coatings (44% for VECD = -5.25 V, 9% for VECD = -5.00 V and 15% for VECD = -4.75 V) and the coverage degree of the lateral spike surfaces (40% for VECD = -5.25 V, 14% for VECD = -5.00 V and 100% for VECD = -4.75 V). XRD confirmed that the multiphasic CaP coating containing crystalline octacalcium phosphate is produced on the lateral surface of the spikes of the MSC-Scaffold. ECDV=const preceded by AAT prevents micro-cracks on the bone-contacting surfaces of the MSC-Scaffold prototype, increases its spikes' lateral surface coverage, and results in the best modification effect at VECD = -5.00 V. To conclude, the biomimetic MSC-Scaffold prototype with desired biomineral coating of native Ca/P ratio was obtained for cementless RA endoprostheses.

Effects of a hydroxyapatite coating on the stability of endosseous implants in rabbit tibiae.

BACKGROUND: A dental implant surface which would promote rapid and strong osseointegration is a key factor of success in modern implantology. To achieve this goal, different implant surface modifications are developed. A hydroxyapatite (HA) coating changing a bioinert titanium surface into bioactive is one of them. OBJECTIVES: The objective of the study was to investigate the effects on bone osseointegration in rabbits resulting from the application of a HA coating deposited on titanium endosseous implants using a modified electrochemical method. MATERIAL AND METHODS: Titanium implants with HA coatings and controls with Al2O3 grit-blasted surfaces were embedded into rabbit tibiae. The chemical composition, roughness and morphology of the implants were determined. Implant stability tests were performed, and the Periotest® value (PTV) and the implant stability quotient (ISQ) value for Osstell Mentor were recorded in order to evaluate the osseointegration. RESULTS: The surface characterization of the implants revealed a microstructure with an arithmetical mean height (Sa) in the range of 0.71-1.04 µm. The HA coating was free of contamination, whereas the controls were enriched with corundum. After healing, a statistically significant increase in the mean ISQ and a decrease in the mean PTV for the HA-coated implants was observed. In the case of the control implants, only PTV decreased significantly with time. CONCLUSIONS: The present study found that implant surface properties affected implant stability as determined by Osstell and Periotest measurements. The HA coating reported herein was found to have chemical and physical properties which appear to improve osseointegration compared to grit-blasted implants.

Ischemia-reperfusion injury and the risk of hepatocellular carcinoma recurrence after deceased donor liver transplantation.

This study aimed to evaluate the effects of ischemia-reperfusion injury (IRI) on the risk of hepatocellular carcinoma (HCC) recurrence after liver transplantation. Data of 195 patients were retrospectively analysed. Post-reperfusion aspartate (AST), alanine transaminase, and lactate dehydrogenase (LDH) levels were the primary measures of IRI. Tumour recurrence was the primary endpoint. Post-reperfusion AST was a continuous risk factor for tumour recurrence in patients within Milan criteria (p = 0.035), with an optimal cut-off of 1896 U/L. Recurrence-free survival of patients within Milan criteria and post-reperfusion AST of <1896 and ≥1896 U/L was 96.6% and 71.9% at 5 and 3.7 years, respectively (p = 0.006). Additionally, post-reperfusion AST and LDH exceeding the upper quartile significantly increased the risk of HCC recurrence in patients within Milan criteria (p = 0.039, hazard ratio [HR] = 5.99 and p = 0.040, HR = 6.08, respectively) and to a lesser extent, in patients within Up-to-7 criteria (p = 0.028, HR = 3.58 and p = 0.039, HR = 3.33, respectively). No other significant IRI effects were found in patients beyond the Up-to-7 criteria and in analyses stratified for independent risk factors for recurrence: tumour number and differentiation, alpha-fetoprotein, and microvascular invasion. Thus, IRI exerts major negative effects on the risk of HCC recurrence after liver transplantation in patients within standard and extended criteria.

Hydroxyapatite coating on titanium endosseous implants for improved osseointegration: Physical and chemical considerations.

BACKGROUND: For many years, hydroxyapatite (HA) has been used as a bioactive endosseous dental implant coating to improve osseointegration. As such, the coating needs to be of high purity, adequate thickness, crystalline, and of a certain roughness in order to stimulate rapid fixation and form a strong bond between the host bone and the implant. There are a number of ways of preparing the HA coating, resulting in various coating properties. Herein, we report the preparation of the HA coating using a direct electrochemical method without the need for subsequent heat treatment. OBJECTIVES: The aim of this study was to investigate the physicochemical properties of the HP coating, deposited on titanium implants by a modified electrochemical method. MATERIAL AND METHODS: The coating was characterized in terms of surface chemical composition, structure, morphology, coating thickness and roughness. RESULTS: The coating was found to be composed of homogenous HA with Ca/P and Ca/O ratios of 1.62 and 0.35, respectively. No other forms of calcium phosphate were detected. The degree of crystallinity of HA was 92.4%. The surface roughness was moderate (Sa = 1.04 µm) with the coating thickness of 2-3 µm. The scanning electron microscopy (SEM) analysis revealed a uniform, integrated layer of rod-like HA crystals with the longitudinal axes parallel to the implant surface. CONCLUSIONS: The coating reported herein was found to have potentially favorable chemical and physical characteristics fostering osseointegration.