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István Lampé,1 Dezső Beke,2 Sándor Biri,3 István Csarnovics,4 Attila Csik,3 Zsuzsanna Dombrádi,5 Péter Hajdu,3 Viktória Hegedűs,6 Richárd Rácz,3 István Varga,7 Csaba Hegedűs11Department of Biomaterials and Prosthetic Dentistry, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary; 2Department of Solid State Physics, University of Debrecen, Debrecen, Hungary; 3Hungarian Academy of Sciences, Institute for Nuclear Research, Debrecen, Hungary; 4Department of Experimental Physics, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary; 5Department of Medical Microbiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary; 6Department of Orthodontics, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary; 7Department of Periodontology, Faculty of Dentistry, University of Debrecen, Debrecen, HungaryObjectives: Using dental Ti implants has become a well-accepted and used method for replacing missing dentition. It has become evident that in many cases peri-implant inflammation develops. The objective was to create and evaluate the antibacterial effect of silver nanoparticle (Ag-NP) coated Ti surfaces that can help to prevent such processes if applied on the surface of dental implants.Methods: Annealing I, Ag ion implantation by the beam of an Electron Cyclotron Resonance Ion Source (ECRIS), Ag Physical Vapor Deposition (PVD), Annealing II procedures were used, respectively, to create a safely anchored Ag-NP layer on 1x1 cm2, Grade 2 titanium samples. The antibacterial effect was evaluated by culturing Staphylococcus aureus (ATCC 29213) on the surfaces of the samples for 8 hours, and comparing the results to that of glass as control and of pure titanium samples. Alamar Blue assay was carried out to check cytotoxicity.Results: It was proved that silver nanoparticles were present on the treated surfaces. The average diameter of the particles was 58 nm, with a 25 nm deviation and Gaussian distribution, the the filling factor was 25%. Antibacterial evaluation revealed that the nanoparticle covered samples had an antibacterial effect of 64.6% that was statistically significant. Tests also proved that the nanoparticles are safely anchored to the titanium surface and are not cytotoxic.Conclusion: Creating a silver nanoparticle layer can be an option to add antibacterial features to the implant surface and to help in the prevention of peri-implant inflammatory processes. Recent studies demonstrated that silver nanoparticles can induce pathology in mammal cells, thus safe fixation of the particles is essential to prevent them from getting into the circulation.Keywords: implants, peri-implant inflammation, oxyde layer, cytocompatibility, antibacterial effect, physical vapor deposition, geometrical model

Objectives: To evaluate the effects of different surface conditioning methods on the immediate repair bond strength and integrity of the repaired composite interface., Methods: One hundred and five resin composite blocks made of a nanohybrid resin composite were randomly assigned to one of the following surface conditioning groups (n = 15/group): Group 1: Gluma Self Etch™ adhesive system, Group 2: Tokuyama Bond Force II™ adhesive system, Group 3: non-roughened and non-conditioned surfaces, Group 4: sandblasting and Gluma Self Etch™, Group 5: sandblasting and Tokuyama Bond Force II™, Group 6: sandblasting only. A positive control group was also used. Resin composite identical to the substrate was applied and the repaired specimens were subjected to shear bond strength (SBS) testing. Representative samples from all groups were subjected to scanning electron microscopy and surface profilometry to determine their mode of failure. The data were analysed statistically using Analysis of Variance (ANOVA) and two independent sample t-test (α = 0.05)., Results: The mean SBS of all test groups ranged between 1.92 and 5.40 MPa and varied with the degree of composite surface roughness and the type of adhesive system employed. Significantly highest SBS values (5.40 ± 0.36 MPa) were obtained in Group 5 (p = 0.017) which were comparable to the coherent strength of the resin composite in the positive control group (p > 0.05)., Conclusions: Under the tested conditions, significantly greater SBS of repaired resin composite was achieved when the substrate surface was conditioned by sandblasting followed by the application of the Tokuyama Bond Force II™ adhesive system., Clinical Significance: Effecting a repair of a nanohybrid composite restoration with sandblasting and the application of TBF II would seem to enhance the interfacial bond strength and integrity of the repaired resin composite interface. Clinical trials are necessary to determine the usefulness of this technique., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Stem cells are present in many tissues, such as dental pulp. Stem cells can be easily isolated from dental pulp because third molars are often removed from patients. Stem cells could be separated from the tissue derived heterogeneous cell population. There are two main methods to separate a cell type from the other ones: the fluorescence activated cell sorting (FACS) and the magnetic activated cell sorting (MACS). The aim of this study was to compare these methods' effect on cell surviving and population growth after sorting on dental pulp cells. The anti-STRO-1 antibody was used as primary antibody to specifically label stem cells. Two secondary antibodies were used: magnetic or fluorescent labelled. We sorted the cells by MACS or by FACS or by combination of both (MACS-FACS). Our results show that the effectivity of MACS and FACS sorting are comparable while of MACS-FACS was significantly higher (MACS 79.53 ± 5.78%, FACS 88.27 ± 3.70%, MACS-FACS 98.43 ± 0.67%). The cell surviving and the post-sorting population growth, on the contrary, are very different. The cell population is growing on first week after MACS but after FACS did not. Moreover, after MACS-FACS, on first week the cell number of population decreased. Taken together, our results suggest to use MACS instead of FACS, at least in case of sorting dental pulp stem cells with anti-STRO-1 antibody.

Background: Ischemia-reperfusion (IR)-induced injury is a frequent sequel of major liver resections. IR injury after prolonged surgical interventions could be the source of increased risk of postoperative morbidity and mortality. Hepatoprotective effects of this new feasible method called remote ischemic perconditioning (RIPER) were investigated in our rat model of IR injury., Materials and Methods: Male Wistar rats underwent ischemia for 60 min on two-thirds of their livers, followed by 1, 6, and 24 h of reperfusion (n = 72, 8 per group). During liver ischemia, but before reperfusion, rats in the treated groups received four cycles of brief infrarenal aortic clamping as perconditioning. Liver microcirculation was monitored by laser Doppler flowmeter parallel with mean arterial pressure measurements. Liver tissue injury and redox homeostasis were investigated. Furthermore, serum tumor necrosis factor alpha (TNF-α) levels were measured., Results: In the RIPER group, compared with the IR group, serum transaminase levels were significantly lower after each reperfusion period (alanine aminotransferase: 1 h, P < 0.001; 6 h, P < 0.05; 24 h, P < 0.01 and aspartate aminotransferase: 1 h, P < 0.001; 6 h, P < 0.05; 24 h, P < 0.05). Reperfusion microcirculatory parameters significantly improved in the perconditioned group compared with those in the IR group (reperfusion area: P = 0.005; maximal plateau: P = 0.0002). Regarding TNF-α levels, significant differences were detected between the two IR injured groups (RIPER versus IR: 1 h, 34.3 ± 12.8 pg/mL versus 205.7 ± 60.9 pg/mL, P < 0.001; 6 h, 60.6 ± 11.7 pg/mL versus 110.4 ± 21.6 pg/mL, P < 0.05). Results of the histologic assessment and redox state measurements also showed favorable changes., Conclusions: Our team firstly reported the protective effects of RIPER on liver morphology, redox homeostasis, and microcirculation and proposed the changes of TNF-α expression., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Introduction: Several techniques have been developed to reduce ischemic-reperfusion injury. A novel method is the remote ischemic perconditioning, applied parallel with target organ ischemia., Aim: The aim of the study was to determine the extent of liver ischemic-reperfusion injury via the application of this novel method., Methods: Male Wistar rats (n = 30, 10/group) were subjected to 60-minute partial liver ischemia and 60-minute reperfusion. Rats in the perconditioned group received conditioning treatment during the last 40 minutes of liver ischemia by infrarenal aortic clamping. Hepatic and lower limb microcirculation was monitored by laser Doppler flowmeter during reperfusion. After reperfusion, liver samples were taken for routine histological examination and redox-state assessment. Serum transaminase activities and liver tissue heat-shock protein-72 expression were measured., Results: Parameters of microcirculation showed significant (p<0.05) improvement in the perconditioned group in comparison with the control. Besides the significant improvement observed in the serum alanine amino-transferase activities, significantly milder tissue injury was detected histologically in the liver sections of the perconditioned group. Moreover, significant improvement was found in the redox-state parameters., Conclusion: Perconditioning may be a reasonable possibility to reduce liver ischemic-reperfusion injury.

Introduction: The ischemia-reperfusion injury of the small intestine is a condition of high mortality, which occurs following superior mesenteric artery (SMA) embolization or circulatory redistribution. The aim of the study was to evaluate the local and systemic effects of postconditioning in a rat model of small intestine ischemia-reperfusion., Methods: Male Wistar rats underwent 60 min ischemia by the clamping of the SMA, followed by 6 hrs of reperfusion. The animals (n = 30) were randomized into three groups: sham-operated, control-, and postconditioned. Postconditioning was performed at the very onset of reperfusion by 6 alternating cycles of 10-10 seconds reperfusion/reocclusion, for a total of 2 min. At the end of the reperfusion blood and tissue (small intestine, lungs, kidney, liver) samples were taken for histological examination. The antioxidant status of small intestine was measured from intestinal homogenates., Results: Histologic results revealed increased damage in control-group lungs, kidney, liver and small intestine in comparison with the postconditioned group. The injury was supported by significantly higher wet/dry weight ratio (p = 0.026), and serum levels of creatinine (p = 0.013), ASAT (p = 0.038), LDH (p = 0.028) and CK (p = 0.038) in the control group. The postconditioned group showed lower serum IL-6 levels (420 pg/ml vs. 188 pg/ml), as well as significantly higher mucosal antioxidant concentration., Conclusions: Postconditioning was able to decrease not only local, but the systemic damage intensity also, after a small intestinal ischemic-reperfusion episode.

Unlabelled: Changes of redox-homeostasis generate cytokines, and free radicals influence many intracellular signaling pathways in different liver diseases. Liophylised table beet and carrot powder (GPS Powder Kft. 1361/004/2003BFÁÉÉÁ) containing bioactive components such as betaine, betanins, betaxanthins, flavonoids, polyphenols, glutamine, beta carotene, vitamins and folic acid may induce changes in various cellular pathways., Aim: The aim of this study was to determine the protecting effects of bioactive agents of the liophylised table beet and carrot powder on fatty liver in a "short term" experiment., Method: Male Wistar rats were fed with chow with or without high fat (2% cholesterol, 0.5% cholic acid, 20% sunflower oil) and treated with 0.1 or 1 g/bwkg/day natural product for ten days parallel with the feedings. Cyclooxygenase-2, inducible nitric oxide synthase and tumor necrosis factor-α mRNA levels were determined using molecular biologic methods. Free radicals, H-donating activity, reducing power and free SH-group concentrations were determined by luminometry and spectrophotometry. Mobilized methyl groups were assayed by high pressure liquid chromatography method in liver homogenates., Results: It was found that the higher dose of the natural product better decreased the induced free radical reactions, cyclooxygenase-2, inducible nitric oxide synthase and tumor necrosis factor-α mRNA-levels both in normal and fatty liver tissues. Although treatments failed to exert significant changes in all global antioxidant parameters, mobilized methyl group concentrations were higher after treatments in fatty liver. Favorable tendencies were also noted in the redox-homeostasis of the fatty liver after treatment., Conclusions: As expected, lyophylised table beet and carrot proved to be a "functional food" in rats with alimentary fat induced fatty liver. It cannot be ruled out that this beneficial effect may have clinical relevance.

To eliminate freezing artifacts in the proximal tubule cells, two cryotechniques were applied to normal rat kidneys, ie, freeze substitution and special freeze drying. In addition, salt depletion and salt loading were applied to groups of rats to evaluate whether the segmental structure of the proximal tubule could be altered. In the superficial part of the renal cortex of normal kidneys, the typical first segment structure in the proximal tubule was generally present in the early postglomerular fraction of the tubule. However, in the second segment, a special cellular phenomenon was constantly present, comprising a significant intercellular space that was easily identified using a light microscope. In the third segment, in which the presence of basolateral interdigitations is minimal, the small lateral space, which was found to be present in cryopreparations between neighboring cells from the normal kidney, was found to be enlarged by heavy salt loading of short duration. It is concluded that these cryotechniques demonstrate quantitative structural variations between superficial and deep nephrons, as well as the presence of extracellular areas between the cells of the second and the third segment, representing a structural background for the essential transport of water from the proximal tubules to the peritubular capillaries.

Background: Postconditioning - using alternating brief cycles of reperfusion/reocclusion applied just at the very beginning of reperfusion - has recently been described as a potent therapeutic technique, attenuating ischaemia-reperfusion injury. In vascular surgery, certain elective interventions involve cross-clamping of major arteries, resulting in temporary ischaemia in large peripheral organs, which thus suffer ischaemia-reperfusion injury. Patients undergoing these operations may develop also serious systemic complications such as multiple distant organ dysfunctions, SIRS, detrimental redistribution of the circulation or even shock, a phenomenon called reperfusion-syndrome. We studied the effects of postconditioning on reperfusion-syndrome in a rodent experimental model., Material and Methods: Anaesthetized male Wistar rats underwent 180 minutes of bilateral lower limb ischaemia and 4 hours of reperfusion using an infrarenal cross-clamping of the abdominal aorta. Control animals underwent no additional intervention. Postconditioning consisted of 6 cycles of 10-second aortic occlusion/10-second declamping starting at the beginning of reperfusion. Haemodynamic parameters were observed with invasive arterial manometer, microcirculation of the lower limb was detected with laser-Doppler-flowmeter. After 4 hours of reperfusion serum, urine, and histological samples were collected., Results: 180-minute ischaemia resulted in significant haemodynamic changes after reperfusion. Postconditioning affected the character of the microcirculatory flow curves, the limb circulation stabilized with hyperaemia after reperfusion. Postconditioning caused a significant reduction in systemic inflammatory response (TNF-alpha, oxygen-derived free radicals). The laboratory and histological samples implied a significant decrease in remote organ (lung and renal) dysfunctions after postconditioning., Conclusion: Postconditioning proves to be capable in conferring protection against different organ injuries caused by longer circulatory occlusions during elective major vascular surgeries.

The background and mechanisms of ischemic acute tubular necrosis are still essentially unclarified. Therefore a quantitative morphological technique was applied for evaluation of the early structural changes in different fractions of the proximal convoluted tubule in the rat renal cortex. In male pentothal-anesthetized Wistar rats (body weight 200-250 g) ischemia of the right kidney was obtained by clamping (clamp diameter 0.15 mm) the ipsilateral renal artery for varying periods of time (10 min to 6 h) followed by removal and instant freezing of the kidney in isopentane at -165 degrees C and subsequent freeze-substitution in alcohol. The microscopic slides from the kidneys were silver methenamine-PAS stained. In the segments of the proximal convoluted tubules of the nephrons, presence of nuclear pyknosis, places of denuded basement membranes and presence of exfoliated tubular cells were counted. The results were statistically treated for comparison between the extent of damage in the initial postglomerular fraction and the later tubular loops. All three parameters showed a systematic, statistically significant increased number of lesions in the initial fraction of the proximal convoluted tubule versus the subsequent loops. The distribution of the structural lesions is in accordance with the previously reported presence of a tubulo-capillary counter-current flow in the proximal convoluted tubule and, when related to the highly variable oxygen tension in the normal renal cortex of the rat, indicates that the peculiar location of the early lesions might well be determined by these functional conditions.

Purpose: The aim of this study was to examine defecographic findings in patients with anal incontinence and constipation and to compare these findings with rectal emptying., Methods: One hundred seventy-five preoperative defecographies documented on videotape in patients with either anal incontinence or constipation were retrospectively reviewed. The examinations were evaluated with respect to anatomic abnormalities of the rectum or anal canal. The results were compared with a semi-quantitative assessment of rectal emptying as it appeared on the video sequence after one minute of strain., Results: Anatomic abnormalities were found equally in incontinent and constipated patients, except for failure to open the anal canal, which was found only in constipated patients. Rectal intussusception was the most frequent finding. Abnormal defecograms were found in both sexes. Enteroceles, sigmoidoceles, and large rectoceles were found only in women. The presence of intussusception, lacking relaxation of the puborectalis muscle, and rectocele did not correlate with poor rectal emptying. Poor rectal emptying was also found in 19 of 58 patients with normal defecograms., Conclusions: Anatomic abnormalities of the rectum may be demonstrated independently of the clinical symptoms and are not always correlated to impaired rectal emptying. Since they may also be found in healthy controls, surgical correction of these abnormalities should be considered only with great caution.

A 7-year experience with radiography-guided blockade of the celiac ganglia in patients suffering from pancreatic pain is described; 36 patients had carcinoma of the pancreas and nine had chronic pancreatitis. The importance of fluoroscopic guidance of deposition of the blocking agent is stressed. The success rate of this procedure is similar to operative intervention for interruption of the pathways of pain conduction. Radiography-guided celiac ganglion block along with enzymatic substitution for increasing pancreatic insufficiency are recommended for effective palliative treatment.

Infarcts of the rabbit kidney were experimentally induced in 22 animals by selective left renal arteriography using the genuine foreign bodies present in the contrast media and catheters as damaging agents. Three days later the infarcts were macroscopically located and measured at laparotomy. Three weeks later the infarcts were macroscopically and microscopically investigated. Small infarcts (below 5 mm diameter) now were rendered grossly invisible, and no fibrous scarring of the infarcted area was present. Histologically, the changes varied from slight atrophy to total lack of microscopical parenchymal changes. Greater infarcts (above 5 mm in diameter) showed traditional cicatricial changes, the degree of scarring being dependent of the initial size of the infarct. Thus the small infarcts were found to be able to regenerate and revascularize.

The incidence of spontaneous postmenopausal fractures and their relationship to menopausal age and bone mass were determined in a representative sample of 70-year-old Danish women. Two hundred and eighty-five women (1.2% of all women in that age group) were examined by case history, by 125I photon absorptiometry in both forearms (BMC), by metacarpal index (CA/TA), and by lateral radiographs of the spine. Twenty-four per cent of the participants had sustained single fractures, and 20% multiple fractures. Nineteen per cent had fractures of the lower forearm, 5% of the proximal humerus, 4% of the hip, and 5% crush fractures of the spine. These comprise Group I fractures, the most definite expressions of osteoporosis. The remaining other long bone fractures (7%) and spinal wedge fractures (18%) comprise Group II fractures. Group I cases were characterized by an earlier onset of the menopause and a definite decrease in bone mass, as judged from BMC and CA/TA, as compared with the nonfracture group. Group II cases did not display this distinction. Of Group I cases, those with multifractures differed from those with single fractures by having a five-year earlier occurrence of first fracture, a further decrease in bone mass, and a slightly raised serum alkaline phosphatase level. Serum calcium and phosphate levels were the same in all groups.

The Jerne technique, a proved method for detecting the number of plaque-forming cells (PFC) in spleen, shows an immunosuppressive effect of phytohemagglutine (PHA) on primary immune response. Kinetic studies are done on 300 NMRI mice, considering the number of PFC/10-8 spleen cells. Significant suppressions of the primary immune response are found if PHA is applied either one day before or together with antigen provided that studies are done 3, 4 or 5 days after immunization with sheep red blood cells (SRBC). The role of activated T-lymphocytes concerning the diminution of immune response is discussed.

Observer variation in interpreting radiograph of the spine in 70-year-old Danish women has been examined. The women joined a general health investigation as part of an epidemiologic screening for osteoporosis. Two experienced radiologists examined independently 280 sets of lateral radiographs of the spine to disclose fractures. The radiographs were examined four times, each examined at two different occasions by each radiologist. Overall intra-observer agreement was 88% and 87% when asked for presence or absence of fractures, irrespective of fracture localization. When accidental occurrence of agreement was taken into account (kappa analysis) intra-observer variation was reduced to 64% and 62%. The overall inter-observer agreement was 75%, but reduced to 47% when accidental occurrence of agreement was noted. Kappa analysis in testing observer variation indicates that a considerable part of agreement can be ascribed to chance alone. This seriously questions the hitherto used definition of osteoporosis.