Microscopic Adhesion Research Articles

Study on low temperature crack resistance of warm-mixed recycled SBS modified asphalt mixtures

In view of the cold winter in northern China and the large temperature difference between day and night, the asphalt pavement has been in low temperature service for a long time, in addition to experiencing the aging effect of water and salt erosion, jointly leading to a particularly serious pavement cracking phenomenon. Therefore, a quantity of Reclaimed Asphalt Pavement (RAP) is produced for the repair and renovation of old roads. Faced with the problems of inadequate reuse rate of RAP and high energy consumption of thermal regeneration, it is of great practical significance to explore the technology of warm mix regeneration. In order to study the adaptability of recycled SBS modified asphalt mixtures to low temperature after complex environmental erosion (long-term aging, water freeze-thaw cycle, and salt freeze-thaw cycle), two mixing methods, including hot mixing and warm mixing, were selected, and a Semi-Circular Bending Test was performed. SCB and Digital Image Correlation (DIC) techniques were used to evaluate the low temperature properties of recycled asphalt mixtures by fracture toughness, fracture energy and horizontal strain density damage. Combined with an Atomic Force Microscope (AFM) test, the microscopic analysis of recycled asphalt was carried out to verify the mechanism of low temperature cracking. The results showed that the low temperature cracking resistance of the reclaimed asphalt mixtures with warm mix was slightly worse than that with hot mix. The overall low temperature cracking resistance of the reclaimed SBS modified asphalt mixtures decreased with the increase in RAP content. The low temperature performance of the warm-mixed reclaimed asphalt mixtures deteriorated greatly when the RAP content was 80 %. The influencing factors of environmental conditions on the low temperature cracking resistance of the warm-mixed recycled SBS modified asphalt mixtures were listed as below: long-term aging > salt freeze-thaw cycle > water freeze-thaw cycle. The influence of salt on the stress field of crack tip and the microstructure of recycled asphalt after freeze-thaw was greater than that of water erosion. The changes of the microscopic adhesion were in good agreement with the macroscopic test results, which could be employed as the index evaluating the low temperature crack resistance of the warm-mixed SBS modified asphalt mixtures. The addition of warm mixing agent would play a positive role in the low temperature crack resistance of recycled asphalt mixtures with a RAP content of less than 60 % to a certain extent, so warm-mixed recycled asphalt mixtures were more suitable for the application in northern areas.

Preparation, nano-mechanics and particle deposition behavior of thin, antifouling hydrogel coatings

Hydrogels based on hydrophilic, crosslinked polymer networks can reduce surface contamination in aqueous environments and continue attracting research interest due to their low adhesion, biocompatibility and tunable properties. In particular, sub-micron hydrogel films can potentially screen a surface from interaction with foulant colloids and microorganisms without compromising original functions, such as water permeation in membranes. This study focuses on the preparation of thin hydrogel films with the goal of understanding their adhesive and micromechanical properties, as well as factors affecting the dynamics of microparticle deposition on such films, mimicking the initial stages of surface fouling with colloids, microparticles and microorganisms. For this purpose, a simple procedure was developed to simultaneously crosslink and covalently anchor multi-arm-PEG precursors to a surface to form a submicron coating as a representative model. The effects of synthetic parameters and external conditions on adhesion and viscoelasticity were studied by force spectroscopy using polystyrene colloidal probes. The same particles were also employed in macroscopic deposition experiments in a parallel plate flow cell under identical solution conditions. Microscopic adhesion and elasticity were unaffected by the hydrogel crosslinking density and by salinity, but strongly affected by solution pH and dwell time, whereas macroscopic deposition was strongly affected both by salinity and by pH. These differences were ascribed to the effect of long-range double-layer forces, involved in deposition but absent in measurements of adhesion and elasticity. The results highlight the differences and similarities between the two types of measurements and underlying phenomena, as a step towards the understanding and rational design of soft antifouling coatings.

Current-carrying wear behavior and the interface evolution of the Cu/Al tribological pair

Cu/Al tribological pairs play a crucial role in maintaining the efficient operation of a wide range of engineering components. However, their durability is often compromised by wear-induced damage, which involves the accumulation of material at the Cu/Al friction interface. This study investigates the intricate wear behavior of Cu/Al tribological pairs under electrical current, with a specific emphasis on material transfer events occurring at the interface. Our findings reveal that the applied electric current exerts a lubricating effect on the sliding contact friction, resulting in reduced adhesive wear. However, it concurrently exacerbates fatigue-induced delamination, abrasive wear, and electrical wear. Through detailed analysis of interface temperatures and microstructure characterizations, we demonstrate that Al deposit adhesion occurs through interfacial metal mixing and nanoscale diffusion in the presence of only mechanical friction. Conversely, at high electrical currents, interfacial melting transpires, resulting in robust adhesion facilitated by the formation of an intermetallic compound. Our findings offer valuable insights into the microscopic adhesion events occurring in Cu/Al tribological pairs and provide guidance for developing innovative coating systems aimed at reducing material deposition in Cu/Al current-carrying friction interfaces.

Molecular dynamics simulation of interfacial adhesion behavior between waterborne epoxy resin emulsified asphalt and aggregate

ABSTRACT Understanding the microscopic adhesion behaviour and mechanism of waterborne epoxy resin emulsified asphalt (WEREA) at the aggregate interface is quite significant for improving the service life of pavements. This work created an interface model of WEREA and aggregate using molecular dynamics (MD) simulation to examine the interface adhesion behavior. The interface model based on MD simulation was used to evaluate the distribution characteristics of asphalt components on the aggregate surfaces by calculating the thermodynamic properties, radial distribution function (RDF), relative concentration (RC) distribution and mean square displacement (MSD). The results show that WEREA has better thermodynamic characteristics than base asphalt and has components with much better self-polymerization behaviour. WEREA adheres more tightly to alkaline aggregates than acidic ones. Van der Waals forces dominate interfacial adhesion to acidic aggregates, while that to alkaline aggregates is dominated by electrostatic forces. Interfacial water damage is a spontaneous reaction. Moisture has a substantial influence on asphalt – aggregate adhesion, especially with alkaline aggregates. This work provides an effective method for exploring WEREA – aggregate adhesion.

Anti-Oil-Adhesion Property of Superhydrophilic/Underwater Superoleophobic Phytic Acid-FeIII Complex Coatings

Crude oil adhesion issues are widespread in the petroleum industry, leading to inefficient production and high maintenance costs. Developing efficient antifouling materials and investigating the microscopic adhesion mechanism are of substantial significance. In the present work, a superhydrophilic/underwater superoleophobic PAFC coating with excellent antifouling properties was constructed by the coordination-driven self-assembly of phytic acid (PA) and FeCl3 (FC). The atomic force microscope (AFM) droplet probe technique was employed to elucidate the underlying mechanism of the anti-oil-adhesion property of the PAFC coating. Results showed that the PAFC modification achieved the optimum effect at a molar ratio of 1:3 between PA and FeIII. Applying a (3-aminopropyl)triethoxysilane (APTES) interlayer can effectively improve the performance of the PAFC coating on silica substrates. AFM droplet probe experiments indicated that the adhesion force between submerged micrometer-sized oil droplets and PAFC-modified substrates was significantly weaker than that with the untreated substrate. Meanwhile, the adhesion forces between oil droplets and surfaces were inversely proportional to the contact angle of the oil in water and were enhanced by higher salinity, lower collision velocity, and stronger loading force. The oil injection and wall sticking tests also confirmed the effectiveness of the PAFC modification in resisting the adhesion of crude oil.

Comparative Assessment of Short-Term Tendon-Scleral Postoperative Inflammation and α-Smooth Muscle Actin Expression following Oral and Topical Diclofenac Administration for Strabismus Surgery in Rabbits

PurposeWound healing and fibrosis modulation are considered pivotal for the long-term outcome of strabismus surgery. Nonsteroidal anti-inflammatory drugs, including diclofenac sodium, are inflammation suppressive drugs that may modulate wound healing, including postoperative inflammation. This study aimed to compare the effect of oral and 0.1% topical diclofenac sodium on short-term inflammation and α-smooth muscle actin (α-SMA) expression at the tendon-scleral attachment site following strabismus surgery in an experimental rabbit model.MethodsSuperior rectus recession was performed in 12 eyes of six New Zealand rabbits. Rabbits were divided into three groups: oral diclofenac 2 × 5 mg/kg for three days (group A), 0.1% diclofenac sodium eye drops 3 times/day for three days (group B), and controls (group C). On postoperative day 14, enucleation was performed. Macroscopic adhesion score, microscopic adhesion score, percentage of postoperative inflammation area (Masson’s trichrome staining), and α-SMA (immunohistochemistry staining) were assessed. Data analysis was performed using a semi-quantitative and quantitative assessment with ImageJ. All groups were compared with reciprocal staining intensity (RSI) values to measure α-SMA expression.ResultsAll groups showed no difference in macroscopic (p = 0.13) and microscopic adhesion scores (p = 0.28). The percentage of postoperative inflammation area in group B (12.44% (8.63–18.29)) was significantly lower than group A (26.76% (21.38–37.56) p = 0.03) and group C (27.80% (16.42–36.28), p = 0.04). Comparative RSI analysis found that group B had a significantly lower α-SMA expression than group C (174.08 ± 21.78 vs 212.58 ± 12.06, p = 0.04).ConclusionThe results suggest that compared to oral, the administration of topical diclofenac showed a more significant reduction of short-term postoperative inflammation and α-SMA expression at the tendon-scleral attachment site following strabismus surgery.

Variation of adsorption effects in coals with different particle sizes induced by differences in microscopic adhesion

The swelling strain caused by methane adsorption in coal affects reservoir permeability, further complicating the propagation of fluid pressure. The impact of different scales of pores in coal on the adsorption behavior was investigated by combining the reaction heat apparatus C80 and atomic force microscopy (AFM), followed by characterization of adsorption effect variation in coals with different particle sizes due to adhesion differences. The results show that the absolute adsorption volume (AAV) of the high-rank coal sample Chengzhuang (CZ) of 0.85–2.00 mm is 1.06 times higher than that of the medium-rank coal sample Qiyi (QY) under the pressure of 4.2 MPa. With the increase of pressure, more desorption occurs at different sites of adsorbed phase, resulting in the increase in the density of the free phase methane increasing the gap between AAV and excess adsorption volume (EAV). The larger the particle size of coal, the smaller the temperature variation during adsorption. In the AFM measurements, CZ containing 2026 adsorption pores exhibits stronger heterogeneity than QY, leading to the formation of more capillary condensation of methane. For the adsorption heat, methane tends to occupy sites with high adsorption potential at the beginning of adsorption to release large amounts of heat. Moreover, the adhesion force distribution of QY is more uniform than that of CZ, mainly concentrated between 1.5 and 3.0 nN. Subject to microscopic adhesion force, methane molecules in the effective adhesion region can be stably adsorbed to pores. Temperature affects the heterogeneity of adhesion, mainly the higher the temperature, the more concentrated the distribution of adhesion in coal. The findings contribute to the clarification of the adsorption kinetics of nanoscale carriers in coal reservoirs.

Elastohydrodynamics of contact in adherent sheets

Adhesive contact between a thin elastic sheet and a substrate arises in a range of biological, physical and technological applications. By considering the dynamics of this process that naturally couples fluid flow, long-wavelength elastic deformations and microscopic adhesion, we analyse a sixth-order thin-film equation for the short-time dynamics of the onset of adhesion and the long-time dynamics of a steadily propagating adhesion front. Numerical solutions corroborate scaling laws and asymptotic analyses for the characteristic waiting time for adhesive contact and for the speed of the adhesion front. A similarity analysis of the governing partial differential equation further allows us to determine the shape of a fluid-filled blister ahead of the adhesion front. Finally, our analysis reveals a near-singular behaviour at the moving elastohydrodynamic contact line with an effective boundary condition that might be useful in other related problems.

Effect of methylene blue on experimental postoperative adhesion: A systematic review and meta-analysis

Adhesion is a primary challenge following surgery, and the anti-adhesive effect of methylene blue (MB) has been investigated. This systematic review and meta-analysis aimed to evaluate the effect of MB on postoperative adhesions in experimental studies. We initially searched OVID-MEDLINE, EMBASE, and Google Scholar in February 2021, and then in May 2021. The anti-adhesive efficacy of MB was compared with that of the control (either placebo or nothing) after the surgical procedure. The primary and secondary outcomes were the macroscopic and microscopic adhesion scores, respectively. Traditional meta-analysis, meta-regression, and trial sequential analysis (TSA) were performed to analyze the retrieved outcomes. We included 13 experimental studies of 367 rats (200 rats received MB and 167 rats received placebo or nothing). The macroscopic adhesion scores were significantly lower in the MB-administered group than in the control group (standardized mean difference, 2.313; 95% confidence interval, 1.104 to3.523; I2 = 94.0%, Tau = 2.059). Meta-regression analysis showed that macroscopic adhesion tended to decrease with an increase in MB dose. TSA demonstrated that the cumulative Z curve crossed both the conventional test and trial sequential monitoring boundary for the macroscopic adhesion score. MB had a beneficial effect on intraperitoneal adhesion following laparotomy, and adhesions decreased with increase in dose.

Theoretical Study on the Contribution of Interfacial Functional Groups to the Adhesive Interaction between Epoxy Resins and Aluminum Surfaces.

To ensure the quality and reliability of products bonded by epoxy resin adhesives, elucidation of the microscopic adhesion mechanism is essential. The adhesive interaction and bonding strength between epoxy resins and hydroxylated γ-alumina (001) surfaces were investigated by using a combined molecular dynamics (MD) and density functional theory (DFT) study. The curing reaction of an epoxy resin consisting of diglycidyl ether of bisphenol A (DGEBA) and 4,4'-diaminodiphenyl sulfone (DDS) was simulated. The resin structure was divided into fragmentary structures to study the interaction of each functional group with the alumina surface using DFT calculations. From the characteristics of the adhesive structures and the calculated adhesion energies, it was found that the fragments forming hydrogen bonds with hydroxy groups on the alumina surface resulted in large adhesion energies. On the other hand, the fragments adsorbed on the alumina surface via dispersion interactions resulted in small adhesion energies. The adhesion forces evaluated from the Hellmann-Feynman force calculations indicated the significant contribution of the hydroxy groups and benzene ether moieties derived from DGEBA to the adhesive stress of the DGEBA/DDS epoxy resin. The direction of hydrogen bonding between the epoxy resin and the surface and the difference in geometry at the interface between the donor and acceptor of hydrogen bonding played a central role in maintaining the adhesive strength during the failure process of the adhesive interface.

The Role of Hypericum Perforatum (St. John's Wort Oil) and Olive Oil in the Prevention of Peritoneal Adhesion in a Rat Model: An Animal Study

Objective: We aimed to investigate Hypericum Perforatum (St. John's Wort Oil) and pure olive oil with respect to their effect on preventing intra-abdominal adhesions after abdominal surgery.Methods: This was an animal study carried out by the Giresun Faculty of Medicine, Department of General Surgery between August 10, 2020, and September 10, 2020. In the study, intra-abdominal adhesion development was examined macroscopically and microscopically on the 14th day after experimental abdominal surgery in three groups [(i) Control, (ii) olive oil application, (iii) St. John's Wort oil application] each consisting of 7 female Wistar Albino rats. Majuzi classification and Zuhlke's microscopic adhesion classification was used to evaluate adhesions.Results: Macroscopically, fibrous bands were not observed in 1 rat in the control group, 2 rats in olive oil recipients, and 1 rat in St. John's Wort oil recipients. A significant difference between the groups was identified in terms of Zuhlke's microscopic adhesion scores (p = 0.026). Accordingly, the adhesion level was significantly reduced in olive oil recipients compared to controls (p = 0.002). There was no significant difference in terms of adhesion between all groups (p>0.05). The Majuzi adhesion classifications in the control group, olive oil group and St. John's wort groups were also similar (p = 0.308).Conclusion: In rats who underwent abdominal surgery, it was determined that intra-abdominal olive oil application reduced the level of adhesion, while St. John's Wort oil application had no effect on adhesion formation.

Mechanical Reliability of Fullerene/Tin Oxide Interfaces in Monolithic Perovskite/Silicon Tandem Cells

High-efficiency perovskite-based solar cells comprise sophisticated stacks of materials which, however, often feature different thermal expansion coefficients and are only weakly bonded at their interfaces. This may raise concerns over delamination in such devices, jeopardizing their long-term stability and commercial viability. Here, we investigate the root causes of catastrophic top-contact delamination we observed in state-of-the-art p-i-n perovskite/silicon tandem solar cells. By combining macroscopic and microscopic analyses, we identify the interface between the fullerene electron transport layer and the tin oxide buffer layer at the origin of such delamination. Specifically, we find that the perovskite morphology and its roughness play a significant role in the microscopic adhesion of the top layers, as well as the film processing conditions, particularly the deposition temperature and the sputtering power. Our findings mandate the search for new interfacial linking strategies to enable mechanically strong perovskite-based solar cells, as required for commercialization.

Variation of Adsorption Effects in Coals with Different Particle Sizes Induced by Differences in Microscopic Adhesion

Variation of Adsorption Effects in Coals with Different Particle Sizes Induced by Differences in Microscopic Adhesion

Effect of intra-abdominal administration of ascites fluid on postoperative peritoneal adhesion in rat model: A randomized controlled trail

IntroductionIntra-abdominal adhesions are typically found after the most surgical procedures. Normally, most adhesions are asymptomatic; however, few individuals experience postoperative adhesion-related problems such as small bowel obstruction, pelvic pain, infertility, or other complications. We aimed to evaluate the preventive effect of the ascites fluid for postoperative peritoneal adhesions in rat models. Material and methodsThis experimental trial was conducted in Sixty Syrian male rat randomly assigned to six groups of 10 animals each as follows: control (group 1&4); normal saline (group 2&5): 2 mL of normal saline was poured into the peritoneal cavity; and case (group 3&6): 2 mL ascites fluid was poured into the peritoneal cavity. All animals in the six groups underwent laparotomy and measurable serosal injury were created with a standard technique. 10 and 30 days after initial surgery, the rats underwent another laparotomy in groups 1, 2, 3 and 4, 5, 6, respectively to assess macroscopic and microscopic adhesions, which were scored by an examiner who was blind to the animals̕ group assignment. Data analyzed by SPSS version 18, using the kruskal Wallis and Bonferroni-corrected Mann-Whitney U tests. P-values of less than 0.05 were considered significant. ResultsThe mean scores of both microscopic and macroscopic adhesion were significantly different between all the groups (P < 0.05). Total macroscopic and microscopic adhesion scores were significantly lower in the ascites fluid treatment than in the control (P = 0.0001) or the normal saline (P < 0.001) group. There was no significant difference between adhesion intensity 10 and 30 days after laparotomy (P > 0.05). ConclusionsAscites fluid can decrease the possibility of post-operative intraperitoneal adhesion formation.

What makes epoxy-phenolic coatings on metals ubiquitous: Surface energetics and molecular adhesion characteristics

HypothesisWetting characteristics of epoxy and phenolic resins on metals depend on the molecular interactions between resins’ functional groups and metal surface. Those interactions affect the practical adhesion strength of epoxy-phenolic coatings on metals. Estimation of the theoretical adhesion energies can reveal this system’s microscopic adhesion mechanisms. ExperimentsAdhesion is estimated theoretically based on resins’ wettability on metals, and experimentally through pull-off adhesion testing of cured coatings. The effect of various functional groups on adhesion is decoupled using epoxy and phenolic resins with different functionalities. To assess the impact of the metal passivation on adhesion, tinplated and tin-free steel substrates are used. Differences in their surface chemical composition and polarity are investigated using XPS. FindingsTheoretical adhesion results reveal a superior adhesion of epoxy compared to phenolic resins. Moreover, epoxy resins having a higher content of epoxide-to-hydroxyl groups show improved theoretical and practical adhesion. The importance of epoxides in driving resins’ initial adhesion on metals is attributed to the formation of direct chemical bonds with active hydrogen on metal surfaces. The adhesion of coatings on tin-free steel is found to be higher than on tinplated steel. This is associated to the increased hydroxyl fraction on tin-free steel surface leading to more hydrogen bonds formation.

Adhesion behavior of oil droplets on solid surface with different wettability and inclined angle in water

Plate separators are widely used for oil-water separation in the petrochemical industry. The microscopic adhesion behavior of oil droplets at the solid surface is the key to understanding the oil-water separation mechanism in the plate separator. However, published microscopic experiments and mechanism research is insufficient. This study experimentally investigates the process of oil droplets impacting solid surfaces of Polytetrafluoroethylene (PTFE), 304 stainless steel, and Polyvinyl chloride using a high-speed camera. The influences of solid surfaces with different wettability and inclined angles from 0° to 45° are studied. The results show that oil droplets have the shortest drainage time and the greatest spreading speed on PTFE plates. The drainage time on an inclined surface is significantly longer than on a horizontal plate, and increases as the angle increases. The maximum spreading length occurs at an inclined angle of 15°, and is less affected by the angle as the Weber number (We) decreases. This study facilitates the understanding of oil droplet adhesion on a coalescing material surface in a plate separator from a microscopic view.

Relation Between Adhesion Properties and Microscopic Characterization of Polyphosphoric Acid Composite SBS Modified Asphalt Binder

The purpose of this study was to investigate the adhesive properties of polyphosphoric acid compounded SBS (PPA/SBS) modified asphalt. Three base asphalt binders, one SBS, one dibutyl phthalate (DBP), one furfural extraction oil, and two polyphosphoric acids (PPA), were used to produce the modified binders. The adhesive properties tested in this study included contact angle, cohesive work, adhesive work, and peak area ratio. Cohesive work and adhesive work indicators were calculated from the contact angle, the contact angle between PPA/SBS modified asphalt and three liquids (distilled water, glycerin, formamide) were tested by the contact angle tester, and the peak area ratio of the microscopic adhesion performance index by AFM. The relation between the microscopic adhesion performance characterization method (peak area ratio) and the macroscopic adhesion performance index (cohesive work, adhesion work) was established. The test results indicated that the PPA/SBS modified asphalt had the highest cohesive work and adhesion work under the conditions of 0.5% PPA, 1% DBP, 1.5% extracted oil, and 3.5% SBS, which was clearly greater than the original SBS modified asphalt, while the peak area ratio was consistent with the cohesive work and adhesive work, in which the correlation coefficient between the peak area ratio and cohesive work was 0.77788, and that between the peak area ratio and adhesion work was 0.87203. We recommend adopting the peak area ratio to characterize PPA/SBS modified asphalt’s microscopic adhesion properties.

Comparison of Large-Gauge Needle, Corneal Knife, and No. 11 Blade for Percutaneous Achillotomy.

In the Ponseti technique, the residual equinus deformity is corrected with percutaneous tenotomy. This experimental study aimed to compare the safety and effectiveness of a large-gauge needle, a corneal knife, and a No. 11 blade in percutaneous achillotomy performed in rats. Ninety Achilles tendons of 45 Sprague-Dawley rats were analyzed, following division into three study groups. In the study, group I (needle), group II (corneal knife), and group III (No. 11 blade) were compared on the basis of bleeding, incision length, requirement for primary suture, range of motion, and resulting neurovascular injury at day 0. Moreover, the groups were compared in terms of range of motion, macroscopic and microscopic adhesions, and tenocyte morphology at days 21 and 42 postoperatively. On day 0, one suture was required in group III, whereas in groups I and II, no sutures were required. Postoperative bleeding was greater in group III and similar in groups I and II. Neurovascular injury was not observed in any of the groups. Three incomplete tenotomies were observed in group III and one incomplete tenotomy was observed in group II. Importantly, all tenotomies were complete in group I. In all groups, the range of motion was similar. The macroscopic adhesion score revealed high adhesion in group III (P = .009). According to Tang's criteria, microscopic adhesion was significantly higher on day 21 in group III compared with the other groups (P <0.001). No significant differences were observed in tenocyte morphology based on the Bonar criteria (P = .850). In the results obtained from this animal study, we observed less bleeding, less adhesion, and less incomplete tenotomy in the large-gauge needle and corneal knife groups compared with the No. 11 blade group during the percutaneous Achilles tenotomy performed in rats.

Effect of pentoxifylline administration on an experimental rat model of intraperitoneal adhesion

Aim: Intraabdominal adhesions are the pathological structures that form between the peritoneal surfaces throughout the healing of the peritoneal surface defects with scar formation. Adhesions are a significant problem because they affect the quality of life, lead to morbidity and mortality, and increase health expenses. We have investigated the effectiveness of pentoxifylline (PTX), which is a methyl xanthine derivative, on the development of experimentally generated intraperitoneal adhesions in rats.Materials and Methods: In our study, 30 Wistar Albino rats, each weighing an average of 200-250 grams, were used. In this study, 3 groups of 10 rats were formed. As the adhesion model, cecotomy method was preferred and applied. Groups were classified as; the sham group, control group and PTX group. In the Sham group, merely laparotomy was applied, the control group was intraperitoneal 5 cc isotonic after the cecotomy, and the PTX group was intraperitoneal 100 mg / kg after the cecotomy. Rats were sacrificed on the 15 th day. Macroscopic, microscopic adhesion and adhesion tissues were evaluated with regard to hydroxyproline levels.Results: In the comparison of the groups from the macroscopic point of view, there was a noteworthy difference in adhesion between the sham group and the PTX group (p = 0.027) and between the control group and the PTX group (p = 0.001).Conclusion: In this study, it was observed that PTX can reduce intraabdominal adhesion and increase the level of hydroxyproline after surgery.

THE EFFECT OF CALCIUM DOBESILATE ON THE PREVENTION OF EXPERIMENTAL INTRA-ABDOMINAL ADHESIONS

ABSTRACT: OBJECTIVE: It was aimed to demonstrate the efficacy of Calcium Dobesilate (Ca-Dob) in preventing postoperative intra-abdominal adhesion formation in an experimental cecal abrasion model. MATERIALS AND METHODS: Thirty female Wistar Albino rats were randomized into 3 groups. In the sham group, the cecum was removed from the abdomen and replaced without any further processing. In the control group, after cecal abrasion and peritoneal resection no processing was applied. In the Ca-Dob group, after cecal abrasion and peritoneal resection, 100 mg/kg/day Ca-Dob was administered. All rats were sacrificed on 21st day. The evaluation of adhesions was made through the degrees of bowel inflammation and fibrosis in tissue samples and the biochemical analysis of tissue and blood samples. RESULTS: Statistically, inflammation, microscopic adhesions and fibrosis scores were found to be significantly lower in the Ca-Dob administered rats compared to the control group (p &amp;lt; 0.05). Tissue MDA, FOP and TOS values were found to be significantly lower statistically compared to the control group (p = 0.001). Tissue total SH values were found to be statistically significantly higher (p &amp;lt; 0.05) in the sham group compared with the control group. Finally; serum MDA and serum TOS values in the Ca-Dob group, was statistically significantly lower (p &amp;lt; 0.05) compared to control group. CONCLUSION: Ca-Dob was found to be efficacious in preventing the formation of adhesions. In addition to the demonstrated anti-inflammatory effect histopathologically, the effect of antioxidant effect demonstrated biochemically was concluded to participate to the adhesion preventive efficacy of Ca-Dob.