[Can dexpanthenol prevent peritoneal adhesion formation? An experimental study].

PubMed

Akdeniz, Yusuf; Tarhan, Omer Ridvan; Barut, Ibrahim

2007-04-01

Peritoneum has an intrinsic fibrinolytic activity that breaks the peritoneal adhesions. Ischemic peritoneal injuries interfere with this fibrinolytic activity. Local application of dexpanthenol, the alcohol form of pantothenic acid (vitamin B5) accelerates wound healing by increasing mitosis. We hypothesized that dexpanthenol would decrease peritoneal adhesions. In rats, antimesenteric border of cecum was abraded with gauze. No medication was given to the control group (n=15). Dexpanthenol was administered intraperitoneally (IP) (n=15, 25 mg/kg, before abdominal closure) or intravenously (IV) (n=15, 25 mg/kg, for 9 days after operation) in the experiment groups. On postoperative day 10, adhesions were graded; activities and concentrations of tissue plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1), tPA/PAI-1 complex and hydroxyproline contents were determined in peritoneum. Adhesion formation was decreased in IP dexpanthenol group compared with control group (p=0.034). tPA concentration and activity and tPA/PAI-1 complex levels were increased in the treated groups compared to controls. PAI-1 levels were similar among the three groups. Peritoneal hydroxyproline levels were lower in animals receiving IV dexpanthenol compared with control animals and in addition, they remained unchanged in IP dexpanthenol treated group (p=0.009, p=0.84, respectively). Our results suggest that dexpanthenol administration through IP may reduce peritoneal adhesion formation probably by altering peritoneal fibrinolytic activity.

The comparison of methylene blue and vitamin E in prevention of abdominal postoperative adhesion formation in rat uterine horn models: Biochemical and histopathologic evaluation.

PubMed

Yildiz, Hamit; Durmus, Ali Said; Simsek, Halil; Yaman, Ihsan

2011-02-01

To compare the effects of vitamin E and 1% methylen blue solutions on prevention of experimentally induced adhesions in rats. Thirty seven female Spraque Dawley rats were randomized into four groups. First group was kept as sham operated group. An adhesion model was constituted on the left uterine horn of the other groups. The lesion areas of rats from the second, the third and the fourth groups were coated with 2 ml 0.9 % saline solution (C group), 10 mg vitamin E (VE group) and 1% methylen blue solutions (MB group), respectively. Histopathologically, adhesion scores, mononuclear cell infiltration, oedema and fibrosis were more prominent in the MB group compared with C and VE groups. There were no significant differences between the groups in tissue glutathione peroxidase (GPx), catalase (CAT) activities and glutation (GSH) level, these parameters were slightly increased in group with VE supplementation though. The administration of VE and MB significantly decreased NO (P<0.01) levels when compared to the C group. The level of malondialdehyde (MDA) in the VE group was significantly lower (P<0.05) than those of the Sh and C groups. Intraperitoneal methylen blue solutions treatments were more effective according to vitamin E in preventing the formation of intra-abdominal adhesion in a rat uterine horn model.

A novel diagnostic aid for intra-abdominal adhesion detection in cine-MR imaging: Pilot study and initial diagnostic impressions.

PubMed

Randall, David; Joosten, Frank; ten Broek, Richard; Gillott, Richard; Bardhan, Karna Dev; Strik, Chema; Prins, Wiesje; van Goor, Harry; Fenner, John

2017-07-14

A non-invasive diagnostic technique for abdominal adhesions is not currently available. Capture of abdominal motion due to respiration in cine-MRI has shown promise, but is difficult to interpret. This article explores the value of a complimentary diagnostic aid to facilitate the non-invasive detection of abdominal adhesions using cine-MRI. An image processing technique was developed to quantify the amount of sliding that occurs between the organs of the abdomen and the abdominal wall in sagittal cine-MRI slices. The technique produces a 'sheargram' which depicts the amount of sliding which has occurred over 1-3 respiratory cycles. A retrospective cohort of 52 patients, scanned for suspected adhesions, made 281 cine-MRI sagittal slices available for processing. The resulting sheargrams were reported by two operators and compared to expert clinical judgement of the cine-MRI scans. The sheargram matched clinical judgement in 84% of all sagittal slices and 93-96% of positive adhesions were identified on the sheargram. The sheargram displayed a slight skew towards sensitivity over specificity, with a high positive adhesion detection rate but at the expense of false positives. Good correlation between sheargram and absence/presence of inferred adhesions indicates quantification of sliding motion has potential to aid adhesion detection in cine-MRI. Advances in Knowledge: This is the first attempt to clinically evaluate a novel image processing technique quantifying the sliding motion of the abdominal contents against the abdominal wall. The results of this pilot study reveal its potential as a diagnostic aid for detection of abdominal adhesions.

The preventive effect of Rofecoxib in postoperative intraperitoneal adhesions.

PubMed

Aldemir, M; Oztürk, H; Erten, C; Büyükbayram, H

2004-02-01

Previous studies showed that nonsteroidal anti-inflammatory (NSAI) drugs suppressed prostaglandin synthesis and were able to prevent adhesion formation following surgical trauma to the peritoneum. The selective suppression inflammatory cascade may prevent adhesion formation. Therefore, we planned this study to experimentally evaluate the effects of Rofecoxib, the selective cyclo-oxygenase-2 inhibitor, in postoperative intraperitoneal adhesions in an animal model. Male Sprague-Dawley rats were divided into three groups of 10. All rats underwent midline laparotomy under ketamine anaesthesia (25 mg/kg im). In group 1 (n = 10), the sham operation group (SG); abdominal walls were closed without any process after 2 minutes. In Group 2 (n = 10), the control group (CG); standard serosal damage was constituted and the abdominal wall was closed. In group 3 (n = 10), the COX-2 group (COXG), after serosal damage, the abdominal wall was closed. A 12 mg/kg/day dose of was given orally to the rats during one week. On the 7th postoperative day, all rats were sacrificed and intra-abdominal adhesions were evaluated both macroscopically and microscopically. Macroscopically, no serious adhesion formations were seen in the SG. Multiple adhesion formations of the CG were significantly more than those of the SG (p < 0.0001). It was determined that adhesions of the COXG diminished (p < 0.0001) when macromorphological adhesion scale results of the COXG were compared with those of the CG. The adhesion scores of the CG were compared microscopically with those of the COXG and granulation tissue formation and fibrosis in the COXG were found to be significantly less than those of the CG (respectively p = 0.002, p < 0.0001). We were of the opinion that Rofecoxib, the selective cyclo-oxygenase inhibitor, was effective in the prevention of postoperative peritoneal adhesions.

Sirolimus-coated, poly(L-lactic acid)-modified polypropylene mesh with minimal intra-peritoneal adhesion formation in a rat model.

PubMed

Lu, S; Hu, W; Zhang, Z; Ji, Z; Zhang, T

2018-05-18

This study evaluated the manufacturing method and anti-adhesion properties of a new composite mesh in the rat model, which was made from sirolimus (SRL) grafts on a poly(L-lactic acid) (PLLA)-modified polypropylene (PP) hernia mesh. PLLA was first grafted onto argon-plasma-treated native PP mesh through catalysis of stannous chloride. SRL was grafted onto the surface of PP-PLLA meshes using catalysis of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and 4-dimethylaminopyridine (DMAP) in a CH 2 Cl 2 solvent. Sprague-Dawley female rats received either SRL-coated meshes, PP-PLLA meshes, or native PP meshes to repair abdominal wall defects. At different intervals, rats were euthanized by a lethal dose of chloral hydrate and adhesion area and tenacity were evaluated. Sections of the mesh with adjacent tissues were assessed histologically. Attenuated total reflection Fourier transformed infrared (ATR-FTIR) spectroscopy indicated the existence of a C=O group absorption peak (1724.1 cm -1 ), and scanning electron microscope morphological analysis indicated that the surface of the PP mesh was covered with SRL. Compared to the native PP meshes and PP-PLLA meshes, SRL-coated meshes demonstrated the greatest ability to decrease the formation of adhesions (P < 0.05) and inflammation. The SRL-coated composite mesh showed minimal formation of intra-abdominal adhesions in a rat model of abdominal wall defect repair.

The Effect of Ethanol Extract of Rose (Rosa damascena) on Intra-abdominal Adhesions After Laparotomy in Rats.

PubMed

Karimi, Mehrdad; Yazdan Asadi, Sayyed; Parsaei, Pouya; Rafieian-Kopaei, Mahmoud; Ghaheri, Hafez; Ezzati, Sareh

2016-05-01

Abdominal adhesions are pathological connections in peritoneal surfaces that are created after abdominal surgery. The aim of this study was to evaluate the inhibitory effect of Rosa damascena extract on adhesions, considering the antioxidant properties of rose. Thirty healthy rats were divided into 3 groups: rats treated by 1% (A) and 5% (B) of R. damascena extract and the con- trol group (C). After administering anesthesia, the abdominal wall was opened and 3 shallow incisions (2 cm) were made on the right wall, and a 2 × 2 piece of peritoneal surface was removed on the left side of the abdominal wall. Then 3 mL of 1% (A) and 5% (B) R. damascena extract was administered into the abdominal cavity. The control group (C) received 3 mL of distilled water. The abdominal cavity was sutured, and a second laparotomy was carried out 14 days later to the created adhesions according to the Canbaz scale, and a histopathologic examination was also performed. All data was analyzed by SPSS volume 16 (Chicago, IL); P less than 0.05 was considered statistically significant. The amount of adhesion in group A was significantly lower than that of group C, 1.4 ± 1.265 versus 3 ± 0.816, (P = 0.007). The histological investigation also showed significant differences in the se- verity of fibrosis (P = 0.029) and inflammation (P = 0.009) between groups A and C; all rats in group B (5%) were found dead. This study indicated the use of R. damascena at a 1% level resulted in a remarkable decrease of intra-abdominal adhesions after laparotomy in rats. Further studies are necessary on this extract and its derivatives for treatment of such diseases in the human model.

[Pathogenesis of adhesions formation after intraabdominal operations].

PubMed

Voskanian, S É; Kyzlasov, P S

2011-01-01

The article describes the pathogenesis of adhesions formation after intraabdominal operations. Described predisposing factors leading of which is mechanical trauma, resulting from the use of surgical instruments, rough manipulations during surgery, damage to the mesothelium by dry gauze etc, which cause the adhesions. The pathogenesis of adhesions formation after intraabdominal surgery is presented in outline form, which described the changes occurring in the body starting with combination of predisposing factors and ending with the development of adhesions with blood vessels by 7-12 days after surgery. At the genetic level predisposition to adhesions formation and development of adhesive disease is treated as a manifestation of rapid acetylation phenotype, in which the intensity of fibrin formation exceeds normal rate of its catabolism. Thus, according to modem concepts, adhesive disease is a separate nosologic unit that dictates the necessity of its detailed study, development and introduction new universal methods of preventing the adhesions formation after intraabdominal operations.

Peritoneal adhesions: etiology, pathophysiology, and clinical significance. Recent advances in prevention and management.

PubMed

Liakakos, T; Thomakos, N; Fine, P M; Dervenis, C; Young, R L

2001-01-01

To summarize the most common etiologic factors and describe the pathophysiology in the formation of peritoneal adhesions, to outline their clinical significance and consequences, and to evaluate the pharmacologic, mechanical, and surgical adjuvant strategies to minimize peritoneal adhesion formation. We performed an extensive MEDLINE search of the internationally published English literature of all medical and epidemiological journal articles, textbooks, scientific reports, and scientific journals from 1940 to 1997. We also reviewed reference lists in all the articles retrieved in the search as well as those of major texts regarding intraperitoneal postsurgical adhesion formation. All sources identified were reviewed with particular attention to risk factors, pathophysiology, clinical manifestations, various methods, and innovative techniques for effectively and safely reducing the formation of postsurgical adhesions. The formation of postoperative peritoneal adhesions is an important complication following gynecological and general abdominal surgery, leading to clinical and significant economical consequences. Adhesion occur in more than 90% of the patients following major abdominal surgery and in 55-100% of the women undergoing pelvic surgery. Small-bowel obstruction, infertility, chronic abdominal and pelvic pain, and difficult reoperative surgery are the most common consequences of peritoneal adhesions. Despite elaborate efforts to develop effective strategies to reduce or prevent adhesions, their formation remains a frequent occurrence after abdominal surgery. Until additional information and findings from future clinical investigations exist, only a meticulous surgical technique can be advocated in order to reduce unnecessary morbidity and mortality rates from these untoward effects of surgery. Copyright 2001 S. Karger AG, Basel

Dura covered with fibrin glue reduces adhesions in abdominal wall defects.

PubMed

Schier, F; Srour, N; Waldschmidt, J

1991-12-01

Dura can greatly facilitate the closure of abdominal wall defects. However, a main disadvantage of its use are the adhesions which develop between omentum, bowel and dura and may lead to bowel obstructions. In this study various groups of rats had either the anterior wall replaced by untreated dura or by dura covered with fibrin glue prior to implantation. Adhesions were found in 75% of sham operated rats, 100% after untreated dura implantation and 50% after the implantation of fibrin glue treated dura.

Comparison of the effects of Mitomycin-C and sodium hyaluronate/carboxymethylcellulose [NH/CMC] (Seprafilm) on abdominal adhesions.

PubMed

Ozerhan, Ismail Hakkı; Urkan, Murat; Meral, Ulvi Mehmet; Unlu, Aytekin; Ersöz, Nail; Demirag, Funda; Yagci, Gokhan

2016-01-01

Intra-abdominal adhesions (IA) may occur after abdominal surgery and also may lead to complications such as infertility, intestinal obstruction and chronic pain. The aim of this study was to compare the effects of Mitomycin-C (MM-C) and sodium hyaluronate/carboxymethylcellulose [NH/CMC] on abdominal adhesions in a cecal abrasion model and to investigate the toxicity of MM-C on complete blood count (CBC) and bone marrow analyses. The study comprised forty rats in four groups (Control, Sham, Cecal abrasion + MM-C, and Cecal abrasion + NH/CMC). On postoperative day 21, all rats except for the control (CBC + femur resection) group, were sacrificed. Macroscopical and histopathological evaluations of abdominal adhesions were performed. In order to elucidate the side effects of MM-C; CBC analyses and femur resections were performed to examine bone marrow cellularity. CBC analyses and bone marrow cellularity assessment revealed no statistically significant differences between MM-C, NH/CMC and control groups. No significant differences in inflammation scores were observed between the groups. The MM-C group had significantly lower fibrosis scores compared to the NH/CMC and sham groups. Although the adhesion scores were lower in the MM-C group, the differences were not statistically significant. Despite its potential for systemic toxicity, MM-C may show some anti-fibrosis and anti-adhesive effects. MM-C is a promising agent for the prevention of IAs, and as such, further trials are warranted to study efficacy.

Effect of Pirfenidone on Vascular Proliferation, Inflammation and Fibrosis in an Abdominal Adhesion Rat Model.

PubMed

Hasdemir, Pinar Solmaz; Ozkut, Mahmud; Guvenal, Tevfik; Uner, Melis Aylin; Calik, Esat; Koltan, Semra Oruc; Koyuncu, Faik Mumtaz; Ozbilgin, Kemal

2017-02-01

To study the efficacy of pirfenidone for prevention of postoperative adhesion formation in an adhesion rat model. Eighteen female Wistar rats were subjected to right-sided parietal peritoneum and right uterine horn adhesion model. Rats were randomized into three groups: group 1 (control) (closure of midline abdominal incision without any agent administration), group 2 (closure of incision after intraperitoneal administration of pirfenidone), and group 3 (closure of incision and only oral administration of pirfenidone for 14 days). Relaparotomy was performed 14 days after the first surgery. Effect of pirfenidone on adhesion formation was assessed on light microscopy by scoring vascular proliferation, inflammation, fibrosis, and collagen formation in the scarred tissue. Effect of pirfenidone on inflammation was assessed by measurement of transforming growth factor-β and interleukin-17 levels in scarred tissue. The degree of vascular proliferation (1.32 ± 0.39 versus 2.34 ± 0.46, p < 0.001), inflammation (1.60 ± 0.70 versus 2.60 ± 0.52, p < 0.01), and fibrosis (1.50 ± 0.53 versus 2.40 ± 0.52, p < 0.01) were less prominent in group 2 compared to group 1, respectively. Only vascular proliferation was found to be less prominent in group 3 compared to group 1 (1.60 ± 0.42 versus 2.34 ± 0.46, p < 0.01). Intraperitoneal and oral administration of pirfenidone reduced tissue levels of inflammatory markers (TGF-β and IL-17) in parietal and visceral peritoneum compared to control group. Intraperitoneal administration of pirfenidone compared to oral administration was more effective in reducing tissue levels of inflammatory markers. Pirfenidone is an effective agent on the prevention of postoperative vascular proliferation, inflammation and fibrosis in scarred tissue particularly with intraperitoneal administration.

A neurokinin 1 receptor antagonist decreases postoperative peritoneal adhesion formation and increases peritoneal fibrinolytic activity.

PubMed

Reed, Karen L; Fruin, A Brent; Gower, Adam C; Stucchi, Arthur F; Leeman, Susan E; Becker, James M

2004-06-15

Fibrous adhesions remain a major sequela of abdominal surgery. The proinflammatory peptide substance P (SP), known to participate in inflammatory events, may play a key role in adhesion formation. This hypothesis was tested by using an antagonist, CJ-12,255 (Pfizer), that blocks the binding of SP to the neurokinin 1 receptor (NK-1R). Adhesion formation was surgically induced in the peritoneum of rats receiving daily doses of the NK-1R antagonist (NK-1RA; 5.0 or 10.0 mg/kg per day) or saline. On postoperative day 7, both the low and high doses of NK-1RA significantly (P < 0.05) reduced adhesion formation by 45% and 53%, respectively, compared with controls. Subsequently, the effect of NK-1RA administration on peritoneal fibrinolytic activity was investigated to determine a potential mechanism for SP action in the peritoneum. Samples were collected from nonoperated controls and from animals 24 h postsurgery that were administered either NK-1RA or saline. Fibrinolytic activity in peritoneal fluid was assayed by zymography, and expression of tissue plasminogen activator (tPA) and plasminogen activator inhibitor 1, both regulators of fibrinolytic activity, was assessed in peritoneal tissue and fluid by RT-PCR and bioassay, respectively. NK-1RA administration led to a marked (P < 0.05) increase in tPA mRNA levels in peritoneal tissue compared with nonoperated and saline-administered animals. Likewise, NK-1RA administration significantly (P < 0.05) increased tPA in the peritoneal fluid. These data suggest that activation of the NK-1R promotes peritoneal adhesion formation by limiting fibrinolytic activity in the postoperative peritoneum, thus enabling fibrinous adhesions to persist.

Biodegradable and thermosensitive monomethoxy poly(ethylene glycol)-poly(lactic acid) hydrogel as a barrier for prevention of post-operative abdominal adhesion.

PubMed

Fu, Shao Zhi; Li, Zhi; Fan, Jun Ming; Meng, Xiao Hang; Shi, Kun; Qu, Ying; Yang, Ling Lin; Wu, Jing Bo; Fan, Juan; Luot, Feng; Qian, Zhi Yong

2014-03-01

Post-operative peritoneal adhesions are serious consequences of abdominal or pelvic surgery and cause severe bowel obstruction, chronic pelvic pain and infertility. In this study, a novel nano-hydrogel system based on a monomethoxy poly(ethylene glycol)-poly(lactic acid) (MPEG-PLA) di-block copolymer was studied for its ability to prevent abdominal adhesion in rats. The MPEG-PLA hydrogel at a concentration of 40% (w/v) was injected and was able to adhere to defect sites at body temperature. The ability of the hydrogel to inhibit adhesion of post-operative tissues was evaluated by utilizing a rat model of abdominal sidewall-cecum abrasion. It was possible to heal wounded tissue through regeneration of neo-peritoneal tissues ten days after surgery. Our data showed that this hydrogel system is equally as effective as current commercialized anti-adhesive products.

The effect of Kombucha on post-operative intra-abdominal adhesion formation in rats.

PubMed

Maghsoudi, Hemmat; Mohammadi, Hussein Benagozar

2009-04-01

Peritoneal adhesions are fibrous bands of tissues formed between organs that are normally separated and/or between organs and the internal body wall after peritoneal injury. The aim of the study was to investigate the effect of intra-peritoneal administration of Kombucha on intra-peritoneal adhesions. Eighty Wistar rats were subjected to standardized lesion by scraping model and were randomly divided into two groups. Group I received no treatment, and Group II received 15 ml of Kombucha solution intra-peritoneally. On the post-operative 14th day adhesion intensity score, inflammatory cell reaction and number of adhesion bands were determined. In the control group, there were no rats with grade 0 and I adhesions. In the group II, there were 26 rats (78.8%) with grade 0-2 adhesions. Adhesion intensity was significantly less in group II (P<0.0001). Number of adhesion bands was significantly less in group II (P<0.001). It was concluded that intra-peritoneal administration of Kombucha might be useful for preventing peritoneal adhesions.

Manual Physical Therapy for Non-Surgical Treatment of Adhesion-Related Small Bowel Obstructions: Two Case Reports

PubMed Central

Rice, Amanda D.; King, Richard; Reed, Evette D’Avy; Patterson, Kimberley; Wurn, Belinda F.; Wurn, Lawrence J.

2013-01-01

Background: Adhesion formation is a widely acknowledged risk following abdominal or pelvic surgery. Adhesions in the abdomen or pelvis can cause or contribute to partial or total small bowel obstruction (SBO). These adhesions deter or prevent the passage of nutrients through the digestive tract, and may bind the bowel to the peritoneum, or other organs. Small bowel obstructions can quickly become life-threatening, requiring immediate surgery to resect the bowel, or lyse any adhesions the surgeon can safely access. Bowel repair is an invasive surgery, with risks including bowel rupture, infection, and peritonitis. An additional risk includes the formation of new adhesions during the healing process, creating the potential for subsequent adhesiolysis or SBO surgeries. Objective: Report the use of manual soft tissue physical therapy for the reversal of adhesion-related partial SBOs, and create an initial inquiry into the possibility of nonsurgical lysis of adhesions. Case Reports: Two patients presenting with SBO symptoms due to abdominal adhesions secondary to abdominal and pelvic surgery were treated with manual soft tissue physical therapy focused on decreasing adhesions. Conclusions: Successful treatment with resolution of symptom presentation of partial SBO and sustained results were observed in both patients treated. PMID:26237678

Abdominal intra-compartment syndrome - a non-hydraulic model of abdominal compartment syndrome due to post-hepatectomy hemorrhage in a man with a localized frozen abdomen due to extensive adhesions: a case report.

PubMed

Bressan, Alexsander K; Kirkpatrick, Andrew W; Ball, Chad G

2016-09-15

Postoperative hemorrhage is a significant cause of morbidity and mortality following liver resection. It typically presents early within the postoperative period, and conservative management is possible in the majority of cases. We present a case of late post-hepatectomy hemorrhage associated with overt abdominal compartment syndrome resulting from a localized functional compartment within the abdomen. A 68-year-old white man was readmitted with sudden onset of upper abdominal pain, vomiting, and hemodynamic instability 8 days after an uneventful hepatic resection for metachronous colon cancer metastasis. A frozen abdomen with adhesions due to complicated previous abdominal surgeries was encountered at the first intervention, but the surgery itself and initial recovery were otherwise unremarkable. Prompt response to fluid resuscitation at admission was followed by a computed tomography of his abdomen that revealed active arterial hemorrhage in the liver resection site and hemoperitoneum (estimated volume <2 L). Selective arteriography successfully identified and embolized a small bleeding branch of his right hepatic artery. He remained hemodynamically stable, but eventually developed overt abdominal compartment syndrome. Surgical exploration confirmed a small volume of ascites and blood clots (1.2 L) under significant pressure in his supramesocolic region, restricted by his frozen lower abdomen, which we evacuated. Dramatic improvement in his ventilatory pressure was immediate. His abdomen was left open and a negative pressure device was placed for temporary abdominal closure. The fascia was formally closed after 48 hours. He was discharged home at postoperative day 6. Intra-abdominal pressure and radiologic findings of intra-abdominal hemorrhage should be carefully interpreted in patients with extensive intra-abdominal adhesions. A high index of suspicion and detailed understanding of abdominal compartment mechanics are paramount for the timely diagnosis of

Histological Analysis of Intra-Abdominal Adhesions Treated with Sodium Hyaluronate and Carboxymethylcellulose Gel.

PubMed

Montalvo-Javé, Eduardo Esteban; Mendoza-Barrera, German Eduardo; García-Pineda, Manuel Alejandro; Jaime Limón, Álvaro Rodrigo; Montalvo-Arenas, César; Castell Rodríguez, Andrés Eliú; Tapia Jurado, Jesús

2016-01-01

To evaluate macro and microscopically the adhesions developed after using the anti-adherence compound sodium hyaluronate and carboxymethylcellulose (SH-CBMC) gel and to determine the volume of the adhesions using a stereological estimation. The study was experimental, random, comparative, and prospective. The subjects of the study were male Wistar rats divided in three groups (n = 10). Group I (control) included rats with no peritoneal injury. Group II rats had a 2 cm diameter injury created bilaterally in the parietal peritoneum at 3 cm from the abdominal midline with electrocautery coated with physiological solution. Group III rats were given the same injuries and coated with SH-CBMC gel. All groups were followed up postoperatively for 30 days, after which a laparotomy was performed to macroscopically determine the presence and type of adhesions. Experimental models were euthanized with anesthetic overdose and biopsies were taken for histopathological examination and stereological estimate of the volume of adhesions. Macroscopic adhesions were 20% less prevalent in Group III compared to Group II, which presented 40% more multiple and firm adhesions, unlike in Group III, in which they were unique and lax. There was a statistically significant decrease in the presence and number of adhesions in rats treated with SH-CBMC gel. Inflammatory infiltrate was significantly lower in rats treated with SH-CBMC gel, but there were no differences in connective tissue, fibrosis, and angiogenesis among groups. There was no statistical difference in the overall volume of adhesions among the treatment groups. SH-CBMC gel reduces macroscopic presence and number of adhesions and the severity of the inflammatory infiltrate.

Rapamycin and a hyaluronic acid-carboxymethylcellulose membrane did not lead to reduced adhesion formations in a rat abdominal adhesion model.

PubMed

Dietrich, Arne; Bouzidi, Maria; Hartwig, Thomas; Schütz, Alexander; Jonas, Sven

2012-06-01

Rapamycin, an immunosuppressive in transplant surgery, has an additional antiproliferative effect. The aim of this study was to investigate the potential protective effects of rapamycin on postoperative adhesion development. Ten rats per group underwent midline incision laparotomy and adhesion induction including bowel sutures. Therapy groups received daily intraperitoneal rapamycin injections (1.5 mg/kg body weight) for 3 weeks postoperatively. Controls were rats without any postoperative treatment, rats receiving the rapamycin solvent or a hyaluronic acid-carboxymethylcellulose membrane (Seprafilm(™)). Postoperative rapamycin application led to enhanced adhesion development and there was a higher rate of wound infections. In addition, Seprafilm(™) did not reduce adhesions, in subgroups there were even more. Rapamycin is not recommendable for perioperative immunosuppression, it enhances adhesion development and leads to a higher rate of wound infections. Surprisingly, the established Seprafilm(™) membrane led to more adhesions in our experimental setting.

Towards radiological diagnosis of abdominal adhesions based on motion signatures derived from sequences of cine-MRI images.

PubMed

Fenner, John; Wright, Benjamin; Emberey, Jonathan; Spencer, Paul; Gillott, Richard; Summers, Angela; Hutchinson, Charles; Lawford, Pat; Brenchley, Paul; Bardhan, Karna Dev

2014-06-01

This paper reports novel development and preliminary application of an image registration technique for diagnosis of abdominal adhesions imaged with cine-MRI (cMRI). Adhesions can severely compromise the movement and physiological function of the abdominal contents, and their presence is difficult to detect. The image registration approach presented here is designed to expose anomalies in movement of the abdominal organs, providing a movement signature that is indicative of underlying structural abnormalities. Validation of the technique was performed using structurally based in vitro and in silico models, supported with Receiver Operating Characteristic (ROC) methods. For the more challenging cases presented to the small cohort of 4 observers, the AUC (area under curve) improved from a mean value of 0.67 ± 0.02 (without image registration assistance) to a value of 0.87 ± 0.02 when image registration support was included. Also, in these cases, a reduction in time to diagnosis was observed, decreasing by between 20% and 50%. These results provided sufficient confidence to apply the image registration diagnostic protocol to sample magnetic resonance imaging data from healthy volunteers as well as a patient suffering from encapsulating peritoneal sclerosis (an extreme form of adhesions) where immobilization of the gut by cocooning of the small bowel is observed. The results as a whole support the hypothesis that movement analysis using image registration offers a possible method for detecting underlying structural anomalies and encourages further investigation. Copyright © 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Silk fibroin hydrogel as physical barrier for prevention of post hernia adhesion.

PubMed

Konar, S; Guha, R; Kundu, B; Nandi, S; Ghosh, T K; Kundu, S C; Konar, A; Hazra, S

2017-02-01

Adhesion formation remains a major complication following hernia repair surgery. Physical barriers though effective for adhesion prevention in clinical settings are associated with major disadvantages, therefore, needs further investigation. This study evaluates silk fibroin hydrogel as a physical barrier on polypropylene mesh for the prevention of adhesion following ventral hernia repair. Peritoneal explants were cultured on silk fibroin scaffold to evaluate its support for mesothelial cell growth. Full thickness uniform sized defects were created on the ventral abdominal wall of rabbits, and the defects were covered either with silk hydrogel coated polypropylene mesh or with plain polypropylene mesh as a control. The animals were killed after 1 month, and the adhesion formation was graded; healing response of peritoneum was evaluated by immunohistochemistry with calretinin, collagen staining of peritoneal sections, and expression of PCNA, collagen-I, TNFα, IL6 by real time PCR; and its adverse effect if any was determined. Silk fibroin scaffold showed excellent support for peritoneal cell growth in vitro and the cells expressed calretinin. A remarkable prevention of adhesion formation was observed in the animals implanted with silk hydrogel coated mesh compared to the control group; in these animals peritoneal healing was complete and predominantly by mesothelial cells with minimum fibrotic changes. Expression of inflammatory cytokines decreased compared to control animals, histology of abdominal organs, haematological and blood biochemical parameters remained normal. Therefore, silk hydrogel coating of polypropylene mesh can improve peritoneal healing, minimize adhesion formation, is safe and can augment the outcome of hernia surgery.

Assessment of adhesion formation after laparoscopic intraperitoneal implantation of Dynamesh IPOM mesh

PubMed Central

Jałyński, Marek; Piskorz, Łukasz; Brocki, Marian

2013-01-01

Introduction Formation of adhesions after laparoscopic hernia repair using the intra-peritoneal onlay mesh (IPOM) procedure can lead to intestinal obstruction or mesh erosion into intestinal lumen. The aims of this study included: measurement of adhesion formation with Dynamesh IPOM after laparoscopic intraperitoneal implantation, and assessment of the occurrence of isolated adhesions at the fastening sites of slowly absorbable sutures. Material and methods Twelve healthy pigs underwent laparoscopic implantation of 2 Dynamesh IPOM mesh fragments each, one was fastened with PDSII, and the other with Maxon sutures. An assessment of adhesion formation was carried out after 6 weeks and included an evaluation of surface area, hardness according to the Zhulke scale, and index values. The occurrence of isolated adhesions at slowly absorbable suture fixation points was also analyzed. Results Adhesions were noted in 83.3% of Dynamesh IPOM meshes. Adhesions covered on average 37.7% of the mesh surface with mean hardness 1.46 and index value 78.8. In groups fixed with PDS in comparison to Maxon sutures adhesions covered mean 31.6% vs. 42.5% (p = 0.62) of the mesh surface, mean hardness was 1.67 vs.1.25 (p = 0.34) and index 85.42 vs. 72.02 (p = 0.95). Conclusions The Dynamesh IPOM mesh, in spite of its anti-adhesive layer of PVDF, does not prevent the formation of adhesions. Adhesion hardness, surface area, and index values of the Dynamesh IPOM mesh are close to the mean values of these parameters for other commercially available 2-layer meshes. Slowly absorbable sutures used for fastening did not increase the risk of adhesion formation. PMID:23847671

Cellular events in adhesion formation due to thermal trauma.

PubMed

Kaplun, A; Aronson, M; Halperin, B; Griffel, B

1984-01-01

Consequent to thermal traumatization of the intestinal wall of the mouse, histopathological events ensue which lead to peritoneal adhesion formation. In the first 48 h, the main pathological findings are of a necrotic and inflammatory nature, but subsequently fibroplasia is the main feature, as evidenced by the appearance of spindle-shaped cells followed by fibroblasts. Factors essential for and contributing to the formation of adhesions are described.

A pectin-honey hydrogel prevents postoperative intraperitoneal adhesions in a rat model.

PubMed

Giusto, Gessica; Vercelli, Cristina; Iussich, Selina; Audisio, Andrea; Morello, Emanuela; Odore, Rosangela; Gandini, Marco

2017-02-17

Adhesions are a common postoperative surgical complication. Liquid honey has been used intraperitoneally to reduce the incidence of these adhesions. However, solid barriers are considered more effective than liquids in decreasing postoperative intra-abdominal adhesion formation; therefore, a new pectin-honey hydrogel (PHH) was produced and its effectiveness was evaluated in a rat cecal abrasion model. Standardized cecal/peritoneal abrasion was performed through laparotomy in 48 adult Sprague-Dawley rats to induce peritoneal adhesion formation. Rats were randomly assigned to a control (C) and treatment (T) group. In group T, PHHs were placed between the injured peritoneum and cecum. Animals were euthanized on day 15 after surgery. Adhesions were evaluated macroscopically and adhesion scores were recorded and compared between the two groups. Inflammation, fibrosis, and neovascularization were histologically graded and compared between the groups. In group C, 17 of 24 (70.8%) animals developed adhesions between the cecum and peritoneum, while in group T only 5 of 24 (20.8%) did (p = 0.0012). In group C, one rat had an adhesion score of 3, sixteen had scores of 2, and seven rats had scores of 0. In group T, four rats had adhesion scores of 2, one rat had an adhesion score of 1 and nineteen have score 0 (p = 0.0003). Significantly lower grades of inflammation, fibrosis, and neovascularization were seen in group T (p = 0.006, p = 0.001, p = 0.002, respectively). PHH is a novel absorbable barrier that is effective in preventing intra-abdominal adhesions in a cecal abrasion model in rats.

Evaluation of polyethylene glycol/polylactic acid films in the prevention of adhesions in the rabbit adhesion formation and reformation sidewall models.

PubMed

Rodgers, K; Cohn, D; Hotovely, A; Pines, E; Diamond, M P; diZerega, G

1998-03-01

To assess the efficacy of bioresorbable films consisting of various polyethylene glycol 6000 and polylactic acid block copolymers on the formation and reformation of adhesions in rabbit models of adhesion development between the sidewall to the adjacent cecum and bowel. The composition of the different polymers was expressed by the number of monomeric units in the block, namely, ethylene oxide (EO) and lactic acid (LA), respectively. Studies of the efficacy of EO/LA films were conducted in rabbit sidewall adhesion formation studies in the presence and absence of blood and in rabbit adhesion reformation studies. REPEL (Life Medical Sciences, Edison, NJ), a film of EO/LA ratio 3.0 manufactured under commercial conditions, was also tested in these animal models. University-based laboratory. New Zealand white rabbits. Placement of films of various EO/LA ratios at the site of injury to the parietal peritoneum. Adhesion formation and reformation. Films of various EO/LA ratios, Seprafilm (Genzyme, Cambridge, MA) and Interceed (Johnson and Johnson Medical, Arlington, TX) placed over an area of excised sidewall at the time of initial injury were highly efficacious in the prevention of adhesion formation. A film of EO/LA ratio 3.7, in contrast with Interceed, was also shown to maintain maximal efficacy in the reduction of adhesion formation in the presence of blood. Further, a film of EO/LA ratio 3.0 produced under commercial conditions, REPEL, was highly efficacious in reducing adhesion development in the rabbit models of adhesion and reformation. These studies suggest that bioresorbable EO/LA films reduced adhesion development in rabbit models of adhesion formation and reformation.

[Abdominal wall reconstruction with collagen membrane in an animal model of abdominal hernia. A preliminary report].

PubMed

Łukasiewicz, Aleksander; Drewa, Tomasz; Skopińska-Wiśniewska, Joanna; Molski, Stanisław

2008-01-01

Abdominal hernia repair is one of the most common surgical procedures. Current data indicate that the best treatment results are achieved with use of synthetic material to reinforce weakened abdominal wall. Prosthetic materials utilized for hernia repair induce adhesions with underlying viscera. They should be therefore separated from them by a layer of peritoneum otherwise adhesions may cause to serious complications such as bowel-skin fistulas. The aim of our work was to determine if implantation of our collagen membrane into abdominal wall defect induce adhesions in rat model of ventral hernia. The collagen film was obtained by acetic acid extraction of rat tail tendons and than casting the soluble fraction onto polyethylene shits. Abdominal wall defect was created in 10 Wistar male rats. Collagen membranes were implanted into the defect using interrupted polypropylene stitches. After 3 months of observation all animals were sacrificed. No adhesions between path structure and bowel developed. In one often rats (10%) adhesion between fixating stitch and omentum was observed. Complete mesothelium lining and vascular ingrowth were microscopically observed within implanted structure. Promising result requires further confirmation in a larger series of animals.

Adhesion barriers at cesarean delivery: advertising compared with the evidence.

PubMed

Albright, Catherine M; Rouse, Dwight J

2011-07-01

Cesarean delivery, the most common surgery performed in the United States, is complicated by adhesion formation in 24-73% of cases. Because adhesions have potential sequelae, different synthetic adhesion barriers are currently heavily marketed as a means of reducing adhesion formation resultant from cesarean delivery. However, their use for this purpose has been studied in only two small, nonblinded and nonrandomized trials, both of which were underpowered and subject to bias. Neither demonstrated improvement in meaningful clinical outcomes. In the only cost-effectiveness analysis of adhesion barriers to date, the use of synthetic adhesion barriers was cost-effective only when the subsequent rate of small bowel obstruction was at least 2.4%, a rate far higher than that associated with cesarean delivery. In fact, intra-abdominal adhesions from prior cesarean delivery rarely cause maternal harm and have not been demonstrated to adversely affect perinatal outcome. Based on our review of the available literature, we think the use of adhesion barriers at the time of cesarean delivery would be ill-advised at the present time.

Adhesions after laparoscopic and open ileal pouch-anal anastomosis surgery for ulcerative colitis.

PubMed

Hull, T L; Joyce, M R; Geisler, D P; Coffey, J C

2012-02-01

Emerging evidence suggests that a laparoscopic approach to colorectal procedures generates fewer adhesions. Even though laparoscopic ileal pouch-anal anastomosis (IPAA) is a lengthy procedure, the prospect of fewer adhesions may justify this approach. The aim of this study was to assess abdominal and adnexal adhesion formation following laparoscopic versus open IPAA in patients with ulcerative colitis. A diagnostic laparoscopy was performed at time of ileostomy closure. All abdominal quadrants and the pelvis were video recorded systematically and graded offline. The incisional adhesion score (IAS; range 0-6) and total abdominal adhesion score (TAS; range 0-10) were calculated, based on the grade and extent of adhesions. Adnexal adhesions were classified by the American Fertility Society (AFS) adhesion score. A total of 43 patients consented to participate, of whom 40 could be included in the study (laparoscopic 28, open 12). Median age was 38 (range 20-61) years. There was no difference in age, sex, body mass index, American Society of Anesthesiologists grade and time to ileostomy closure between groups. The IAS was significantly lower after laparoscopic IPAA than following an open procedure: median (range) 0 (0-5) versus 4 (2-6) respectively (P = 0·004). The TAS was also significantly lower in the laparoscopic group: 2 (0-6) versus 8 (2-10) (P = 0·002). Applying the AFS score, women undergoing laparoscopic IPAA had a significantly lower mean(s.d.) prognostic classification score than those in the open group: 5·2(3·7) versus 20·0(5·6) (P = 0·023). Laparoscopic IPAA was associated with significantly fewer incisional, abdominal and adnexal adhesions in comparison with open IPAA. Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

Effects of Alcohol on Pericardial Adhesion Formation in Hypercholesterolemic Swine

PubMed Central

Lassaletta, Antonio D.; Chu, Louis M.; Sellke, Frank W.

2012-01-01

Objective Re-operative cardiac surgery is complicated in part because of extensive adhesions encountered during the second operation. The purpose of this study was to examine the effects of alcohol with and without resveratrol (red wine vs. vodka), on post-operative pericardial adhesion formation in a porcine model of hypercholesterolemia and chronic myocardial ischemia. Methods Male Yorkshire swine were fed a high-cholesterol diet to simulate conditions of coronary artery disease followed by surgical placement of an ameroid constrictor to induce chronic ischemia. Post-operatively, control pigs continued their high-cholesterol diet alone, while the two experimental groups had diets supplemented with either red wine or vodka. Seven weeks after ameroid placement, all animals underwent re-operative sternotomy. Results Compared to controls, pericardial adhesion grade was markedly reduced in the vodka group while there was no difference in the wine group. Intramyocardial fibrosis was significantly reduced in the vodka group compared to controls. There was no difference in expression of proteins involved in focal adhesion formation between any groups (FAK, Int α5, Int β1, Paxillin, Vinculin, PYK2, PKCε, p-PKCε). The wine group exhibited elevated CRP levels vs. control and vodka group. Conclusions Post-operative vodka consumption markedly reduced the formation of pericardial adhesions and intramyocardial fibrosis while red wine had no effect. Analysis of protein expression did not reveal any obvious explanation for this phenomenon, suggesting a post-translational effect of alcohol on fibrous tissue deposition. The difference in adhesion formation in the vodka vs. wine groups may be due to increased inflammation in the wine group. PMID:22244558

Adhesion formation after previous caesarean section-a meta-analysis and systematic review.

PubMed

Shi, Z; Ma, L; Yang, Y; Wang, H; Schreiber, A; Li, X; Tai, S; Zhao, X; Teng, J; Zhang, L; Lu, W; An, Y; Alla, N R; Cui, T

2011-03-01

The optimal technique for performing caesarean section with respect to minimising postoperative adhesions has not been determined. To evaluate adhesion formation for three common caesarean section techniques in women undergoing repeat caesarean section surgeries. A database was constructed from Medline, EMBASE, Cochrane Library, National Science Digital Library, China Biological Medicine Database and through contact with experts in this field from January 1990 to May 2010. Studies were included if they examined adhesion formation in repeat caesarean sections as a primary objective, delineated a clear study design, specified an adhesion scoring system, and had sufficient patient exclusion criteria. We abstracted data regarding adhesion formation. The Mantel-Haenszel random-effects model was employed for all analyses using odds ratio or inverse variance, along with 95% CI. Thirty-three qualified studies including 4423 women were analysed. There were 406 adhesions among 571 women and 238 adhesions among 596 women in the Stark's caesarean section (also known as Misgav-Ladach method) group and modified Stark's caesarean section group, respectively, with pooled OR 4.69 (95% CI 3.32-6.62; P < 0.01, 12 studies); 1173 adhesions among 1555 women and 1179 adhesions among 1625 women in Stark's caesarean section group and classic lower-segment caesarean section group, respectively, with pooled odds ratio 1.28 (95% CI 0.97-1.68; P = 0.08, 21 studies); and 29 adhesions from 102 women and 115 adhesions from 193 women in modified Stark's caesarean section group and classic lower-segment caesarean section group, respectively, with pooled odds ratio 0.28 (95% CI 0.10-0.82; P = 0.02, two studies). Closure of the peritoneum in modified Stark's caesarean section resulted in less adhesion formation and should be recommended. © 2010 The Authors Journal compilation © RCOG 2010 BJOG An International Journal of Obstetrics and Gynaecology.

Adhesion, biofilm formation, cell surface hydrophobicity, and antifungal planktonic susceptibility: relationship among Candida spp.

PubMed

Silva-Dias, Ana; Miranda, Isabel M; Branco, Joana; Monteiro-Soares, Matilde; Pina-Vaz, Cidália; Rodrigues, Acácio G

2015-01-01

We have performed the characterization of the adhesion profile, biofilm formation, cell surface hydrophobicity (CSH) and antifungal susceptibility of 184 Candida clinical isolates obtained from different human reservoirs. Adhesion was quantified using a flow cytometric assay and biofilm formation was evaluated using two methodologies: XTT and crystal violet assay. CSH was quantified with the microbial adhesion to hydrocarbons test while planktonic susceptibility was assessed accordingly the CLSI protocol for yeast M27-A3 S4. Yeast cells of non-albicans species exhibit increased ability to adhere and form biofilm. However, the correlation between adhesion and biofilm formation varied according to species and also with the methodology used for biofilm assessment. No association was found between strain's site of isolation or planktonic antifungal susceptibility and adhesion or biofilm formation. Finally CSH seemed to be a good predictor for biofilm formation but not for adhesion. Despite the marked variability registered intra and inter species, C. tropicalis and C. parapsilosis were the species exhibiting high adhesion profile. C. tropicalis, C. guilliermondii, and C. krusei revealed higher biofilm formation values in terms of biomass. C. parapsilosis was the species with lower biofilm metabolic activity.

Adhesion, biofilm formation, cell surface hydrophobicity, and antifungal planktonic susceptibility: relationship among Candida spp.

PubMed Central

Silva-Dias, Ana; Miranda, Isabel M.; Branco, Joana; Monteiro-Soares, Matilde; Pina-Vaz, Cidália; Rodrigues, Acácio G.

2015-01-01

We have performed the characterization of the adhesion profile, biofilm formation, cell surface hydrophobicity (CSH) and antifungal susceptibility of 184 Candida clinical isolates obtained from different human reservoirs. Adhesion was quantified using a flow cytometric assay and biofilm formation was evaluated using two methodologies: XTT and crystal violet assay. CSH was quantified with the microbial adhesion to hydrocarbons test while planktonic susceptibility was assessed accordingly the CLSI protocol for yeast M27-A3 S4. Yeast cells of non-albicans species exhibit increased ability to adhere and form biofilm. However, the correlation between adhesion and biofilm formation varied according to species and also with the methodology used for biofilm assessment. No association was found between strain's site of isolation or planktonic antifungal susceptibility and adhesion or biofilm formation. Finally CSH seemed to be a good predictor for biofilm formation but not for adhesion. Despite the marked variability registered intra and inter species, C. tropicalis and C. parapsilosis were the species exhibiting high adhesion profile. C. tropicalis, C. guilliermondii, and C. krusei revealed higher biofilm formation values in terms of biomass. C. parapsilosis was the species with lower biofilm metabolic activity. PMID:25814989

Prevention of adhesion bands by ibuprofen-loaded PLGA nanofibers.

PubMed

Jamshidi-Adegani, Fatemeh; Seyedjafari, Ehsan; Gheibi, Nematollah; Soleimani, Masoud; Sahmani, Mehdi

2016-07-08

In this study, prevention of the adhesion bands and inflammatory features has been investigated using poly (lactic-co-glycolic acid)-ibuprofen (PLGA-IB) nanofibrous meshes in a mice model. To find the optimized membrane for prevention of postoperative adhesion bands, we have compared PLGA-IB group with PLGA, IB, and control groups in a mice adhesion model. Two scoring adhesion systems were used to represent the outcome. According to the results obtained in this study, the PLGA-IB nanofiber membrane showed a greater reduction in adhesion band than other groups. In conclusion, among FDA-approved polymers and drugs, PLGA-IB meshes could be applicable as a potential candidate for prevention of postoperative abdominal inflammation and adhesion bands formation. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:990-997, 2016. © 2016 American Institute of Chemical Engineers.

Administration of honey to prevent peritoneal adhesions in a rat peritonitis model.

PubMed

Yuzbasioglu, Mehmet Fatih; Kurutas, Ergul Belge; Bulbuloglu, Ertan; Goksu, Mustafa; Atli, Yalcin; Bakan, Vedat; Kale, Ilhami Taner

2009-02-01

We investigated the effects of intraperitoneal honey on the development of postoperative intra-abdominal adhesions and oxidative stress in a model of bacterial peritonitis. Bacterial peritonitis was induced in 18 rats by cecal ligation and puncture. The rats were randomly assigned to three groups. Group 1 (n=6) received honey intraperitoneally, group 2 (n=6) received 5% dextrose intraperitoneally, and the third group received no fluid or medicine intraperitoneally one day after cecal ligation and puncture procedure. All animals were killed 14 days later so we could assess the adhesion score. Tissue antioxidant levels were measured in 1-g tissue samples taken from the abdominal wall. Adhesion scores of honey treated group were significantly lower according to the control group (P<0.05) and statistically significant. Adhesion scores of honey were lower from 5% dextrose but not statistically significant (P>0.05). Malondialdehyde values of honey group were significantly lower from the control group (P<0.05) and levels in 5% dextrose group was higher than the honey group. Catalase levels were high in control and 5% dextrose groups. Superoxide dismutase levels were higher in the control group than the honey group (statistically significant). Intraperitoneal honey decreased the formation of postoperative intra-abdominal adhesions without compromising wound healing in this bacterial peritonitis rat model. Honey also decreased the oxidative stress during peritonitis.

Post-operative adhesions after digestive surgery: their incidence and prevention: review of the literature.

PubMed

Ouaïssi, M; Gaujoux, S; Veyrie, N; Denève, E; Brigand, C; Castel, B; Duron, J J; Rault, A; Slim, K; Nocca, D

2012-04-01

Post-operative adhesions after gastrointestinal surgery are responsible for significant morbidity and constitute an important public health problem. The aim of this study was to review the surgical literature to determine the incidence, consequences and the variety of possible countermeasures to prevent adhesion formation. A systematic review of English and French language surgical literature published between 1995 and 2009 was performed using the keywords "adhesion" and "surgery". Peritoneal adhesions are reported as the cause of 32% of acute intestinal obstruction and 65-75% of all small bowel obstructions. It is estimated that peritoneal adhesions develop after 93-100% of upper abdominal laparotomies and after 67-93% of lower abdominal laparotomies. Nevertheless, only 15-18% of these adhesions require surgical re-intervention. The need for re-intervention for adhesion-related complications varies depending on the initial type of surgery, the postoperative course and the type of incision. The laparoscopic approach appears to decrease the risk of adhesion formation by 45% and the need for adhesion-related re-intervention to 0.8% after appendectomy and to 2.5% after colorectal surgery. At the present time, only one product consisting of hyaluronic acid applied to a layer of carboxymethylcellulose (Seprafilm(®)) has been shown to significantly reduce the incidence of postoperative adhesion formation; but this product is also associated with a significant increase in the incidence of anastomotic leakage when the membrane is applied in direct contact with the anastomosis. The use of this product has not been shown to decrease the risk of re-intervention for bowel obstruction. The prevention of postoperative adhesions is an important public health goal, particularly in light of the frequency of this complication. The routine use of anti-adhesion products is not recommended given the lack of studies with a high level of evidence concerning their efficacy and safety of

Validation of a coding algorithm for intra-abdominal surgeries and adhesion-related complications in an electronic medical records database

PubMed Central

Scott, Frank I; Mamtani, Ronac; Haynes, Kevin; Goldberg, David S; Mahmoud, Najjia N.; Lewis, James D

2016-01-01

PURPOSE Epidemiological data on adhesion-related complications following intra-abdominal surgery are limited. We tested the accuracy of recording of these surgeries and complications within The Health Improvement Network (THIN), a primary care database within the United Kingdom. METHODS Individuals within THIN from 1995–2011 with an incident intra-abdominal surgery and subsequent bowel obstruction (SBO) or adhesiolysis were identified using diagnostic codes. To compute positive predictive values (PPVs), requests were sent to treating physicians of patients with these diagnostic codes to confirm the surgery, SBO, or adhesiolysis code. Completeness of recording was estimated by comparing observed surgical rates within THIN to expected rates derived from the Hospital Episode Statistics (HES) dataset within England. Cumulative incidence rates of adhesion-related complications at 5 years were compared to a previously published cohort within Scotland. RESULTS 217 of 245 (89%) questionnaires were returned (180 SBO and 37 adhesiolysis). The PPV of codes for surgery was 94.5% (95%CI: 91–97%). 88.8% of procedure types were correctly coded. The PPV for SBO and adhesiolysis was 86.1% (95% CI: 80–91%) and 89.2% (95% CI: 75–97%), respectively. Colectomy, appendectomy, and cholecystectomy rates within THIN were 99%, 95%, and 84% of rates observed in national HES data, respectively. Cumulative incidence rates of adhesion related complications following colectomy, appendectomy, and small bowel surgery were similar to those published previously. CONCLUSIONS Surgical procedures, SBO, and adhesiolysis can be accurately identified within THIN using diagnostic codes. THIN represents a new tool for assessing patient-specific risk factors for adhesion-related complications and long term outcomes. PMID:26860870

Ionic requirements for membrane-glass adhesion and giga seal formation in patch-clamp recording.

PubMed

Priel, Avi; Gil, Ziv; Moy, Vincent T; Magleby, Karl L; Silberberg, Shai D

2007-06-01

Patch-clamp recording has revolutionized the study of ion channels, transporters, and the electrical activity of small cells. Vital to this method is formation of a tight seal between glass recording pipette and cell membrane. To better understand seal formation and improve practical application of this technique, we examine the effects of divalent ions, protons, ionic strength, and membrane proteins on adhesion of membrane to glass and on seal resistance using both patch-clamp recording and atomic force microscopy. We find that H(+), Ca(2+), and Mg(2+) increase adhesion force between glass and membrane (lipid and cellular), decrease the time required to form a tight seal, and increase seal resistance. In the absence of H(+) (10(-10) M) and divalent cations (<10(-8) M), adhesion forces are greatly reduced and tight seals are not formed. H(+) (10(-7) M) promotes seal formation in the absence of divalent cations. A positive correlation between adhesion force and seal formation indicates that high resistance seals are associated with increased adhesion between membrane and glass. A similar ionic dependence of the adhesion of lipid membranes and cell membranes to glass indicates that lipid membranes without proteins are sufficient for the action of ions on adhesion.

Acellular derivatives of mesenchymal stem cells prevent peritoneal adhesions in an animal model.

PubMed

Rojo, Daniel; Conget, Paulette

2018-03-01

Peritoneal adhesions are nonanatomical connections that bind organs to the abdominal wall or among them. They arise after peritoneal injury, which triggers an inflammatory response followed by a healing process that leads to fibrotic tissue formation. Mesenchymal stem cells and their secretion products, also referred to as acellular derivatives (ACDs), have anti-inflammatory, fibrinolytic, and antifibrogenic properties. The aim of this study was to determine the effect of intraoperative administration of ACD on the appearance, severity, and progression of peritoneal adhesions, in an animal model. Cecal erosions were mechanically induced in adult mice. Before closure, the vehicle, ACD, or Seprafilm was administered. Seven days later, the presence and grade of peritoneal adhesions were assessed macroscopically. One, 3, and 7 d after intervention, molecular and cellular markers of inflammation, fibrinolysis, and fibrogenesis were evaluated both locally and systemically. ACDs avoided the appearance of clinically relevant peritoneal adhesions. The vehicle had no effect, and Seprafilm reduced them inconsistently. The antiadhesive effect of ACD was associated with an early reduction of proinflammatory cytokine (tumor necrosis factor-alpha and interferon-gamma) secretion and leukocyte (polymorphonuclears, mononuclears, and macrophages) infiltration. High levels of D-dimer, low fibrin deposits, low myofibroblasts infiltration, and less fibrosis were also observed. ACD administered at the end of abdominal surgeries prevents the formation of peritoneal adhesions due to the modulation of inflammatory, fibrinolytic, and fibrogenic processes. Copyright © 2017 Elsevier Inc. All rights reserved.

A Chitosan-Based Sinus Sealant for Reduction of Adhesion Formation in Rabbit and Sheep Models

PubMed Central

Medina, Jennifer G.; Steinke, John W.; Das, Subinoy

2013-01-01

Objective Chronic sinusitis is the most prevalent chronic disease in the United States in adults aged 18 to 44 years, with approximately 250,000 operations performed annually. Although often successful, sinus surgery fails in greater than 15% of patients. Adhesion formation is a common complication and cause for subsequent revision surgery. Here, the authors evaluate a sprayable chitosan/starch-based sinus sealant and demonstrate its ability to reduce adhesion formation both in vitro and in 2 animal models. Study Design Randomized, controlled, animal trials. Setting Academic medical center (fibroblast experiments) and animal laboratories (sheep and rabbit studies). Subjects and Methods This sinus sealant was applied to human cultured fibroblasts obtained from surgically removed polyps to examine its ability to inhibit fibroblast migration and proliferation. The sinus sealant was applied to New Zealand White rabbits (n = 20) in an established cecal-sidewall abrasion model and to sheep (n = 10) in a sinus surgical adhesion model to examine its ability to reduce adhesion formation. Results This sinus sealant inhibited migration and proliferation of human cultured fibroblasts and reduced the total adhesion score from 4.9 to 0.3 for a total reduction of 94% (95th percentile confidence interval [CI], 78%, 100%; P < .001) in a well-established rabbit cecal-sidewall model commonly used for adhesion testing. Moreover, this sealant reduced adhesion formation from 80% to 10% for a total reduction of 70% (95th percentile CI, 57%, 93%; P = .003) in a sheep sinus adhesion surgical model. Conclusion This chitosan-based sealant demonstrates promise for reducing adhesion formation in sinus surgery. PMID:22492298

Application of hyaluronic acid/sodium alginate-based microparticles to prevent tissue adhesion in a rabbit model.

PubMed

Back, Ja Hoon; Cho, Wan Jin; Kim, Jun Ho; Park, Il Kyu; Kwon, Sung Won

2016-04-01

Postsurgical adhesion formation is a concern in every field of surgery. We evaluated the efficacy of hyaluronic acid/sodium alginate-based microparticle anti-adhesive agents (MP) for the prevention of postsurgical adhesion formation in a standardized rabbit model. To evaluate the anti-adhesion effect, a uterus-abdominal wall abrasion model was created in rabbits. On the surface of the injured uterus, an anti-adhesive agent, Interceed(®) or MP, was applied (positive control and study groups, respectively; n = 10 each). In another group of 10 animals, neither agent was applied (negative control group). The adhesion levels were graded 3 weeks after surgery. Acute and chronic toxicity was also evaluated. The grade of adhesion was significantly lower in the MP group than in the negative control and positive control groups. No evidence of acute or chronic toxicity induced by this material was found in blood and tissue analysis. MP shows potential as an effective novel type of resorbable biomaterial to reduce postoperative adhesion. The easy placement and handling of this material make the MP powder attractive as a tissue adhesion barrier.

Levorotatory carbohydrates and xylitol subdue Streptococcus mutans and Candida albicans adhesion and biofilm formation.

PubMed

Brambilla, Eugenio; Ionescu, Andrei C; Cazzaniga, Gloria; Ottobelli, Marco; Samaranayake, Lakshman P

2016-05-01

Dietary carbohydrates and polyols affect the microbial colonization of oral surfaces by modulating adhesion and biofilm formation. The aim of this study was to evaluate the influence of a select group of l-carbohydrates and polyols on either Streptococcus mutans or Candida albicans adhesion and biofilm formation in vitro. S. mutans or C. albicans suspensions were inoculated on polystyrene substrata in the presence of Tryptic soy broth containing 5% of the following compounds: d-glucose, d-mannose, l-glucose, l-mannose, d- and l-glucose (raceme), d- and l-mannose (raceme), l-glucose and l-mannose, sorbitol, mannitol, and xylitol. Microbial adhesion (2 h) and biofilm formation (24 h) were evaluated using MTT-test and Scanning Electron Microscopy (SEM). Xylitol and l-carbohydrates induced the lowest adhesion and biofilm formation in both the tested species, while sorbitol and mannitol did not promote C. albicans biofilm formation. Higher adhesion and biofilm formation was noted in both organisms in the presence of d-carbohydrates relative to their l-carbohydrate counterparts. These results elucidate, hitherto undescribed, interactions of the individually tested strains with l- and d-carbohydrates, and how they impact fungal and bacterial colonization. In translational terms, our data raise the possibility of using l-form of carbohydrates and xylitol for dietary control of oral plaque biofilms. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of sugammadex on the prevention of postoperative peritoneal adhesions.

PubMed

Şahin, Hasan; Toman, Hüseyin; Kiraz, Hasan Ali; Şimşek, Tuncer; Erbaş, Mesut; Özkul, Faruk; Arık, Muhammet Kasım; Hancı, Volkan

2015-09-01

Many materials and techniques have been used to prevent and repair intra-abdominal adhesions, but an effective solution has not been found. The aim of this study is to research the effect of sugammadex on intra-abdominal adhesions in an experimentally induced intra-abdominal adhesion model. Twenty-four female Wistar albino rats were included in the study. The experimental animals were randomly divided into three groups: the sugammadex group (Group SX, n = 8), the control group (Group C, n = 8), and the sham group (Group S, n = 8). After starvation for 1 night, the rats were injected with a 50 mg/kg intramuscular dose of ketamine and a 5 mg/kg intramuscular dose of xylazine for anesthesia. The rats in the SX group were given 3 mL sugammadex into the peritoneal cavity, while rats in the control group were given 3 mL 0.9% sodium chloride. In the sham group, the peritoneal cavity was opened, but no chemicals were administered. All rats were sacrificed on the 10(th) postoperative day. The adhesions were staged as 0, 1, 2, and 3 according to Evans et al.'s model. Our evaluation of macroscopic adhesion intensity found statistically significant differences between the groups. The sugammadex group was observed to have fewer adhesions in a statistically significant manner compared with the control group (p < 0.05). In our experimental intra-abdominal adhesion model in rats, we observed that sugammadex prevented postoperative intra-abdominal adhesions. Copyright © 2015. Published by Elsevier Taiwan.

The extent of adhesion induction through electrocoagulation and suturing in an experimental rat study.

PubMed

Wallwiener, Christian W; Kraemer, Bernhard; Wallwiener, Markus; Brochhausen, Christoph; Isaacson, Keith B; Rajab, Taufiek K

2010-03-01

To investigate the effect of three types of peritoneal trauma occurring during surgery (high-frequency bipolar current, suturing, and mechanical damage) on postoperative adhesion formation in a rodent animal model. Randomized, controlled experimental trial in an in vitro animal model. Laboratory facilities of a university department of obstetrics and gynecology. Thirty-five female Wistar rats. Bilateral experimental lesions were created on the abdominal wall in every animal. The effect of minimal electrocoagulation was examined by creating lesions (n = 14) through sweeps of a bipolar forceps with a duration of 1 second and standardized pressure. For extensive electrocoagulation standardized lesions (n = 14) were created using sweeps of a duration of 3 seconds and three times more pressure. For mechanical trauma, standardized lesions (n = 14) were created by denuding the peritoneum mechanically. To study the additive effect of suturing, experimental lesions were created by suturing plus minimal electrocoagulation (n = 14) or mechanical denuding (n = 14). Adhesion incidence, quantity, and quality of the resulting adhesions were scored 14 days postoperatively. Adhesions were studied histopathologically. Mechanical denuding of the peritoneum did not result in adhesion formation. After minimal electrocoagulation, mean adhesion quantity of the traumatized area averaged 0%. This contrasted with extensive electrocoagulation, where there was 50% adhesion. Additional suturing increased mean adhesion quantity to 73% and 64% for superficial electrocoagulation and mechanical denuding, respectively. We conclude that superficial trauma limited mostly to the parietal peritoneum may be a negligible factor in adhesion formation in this model. This appears to be irrespective of the mode of trauma. However, additional trauma to the underlying tissues, either by deeper electrocoagulation or suturing, leads to significantly increased adhesion formation. These data also show that there

Contraction of Abdominal Wall Muscles Influences Incisional Hernia Occurrence and Size

PubMed Central

Lien, Samuel C.; Hu, Yaxi; Wollstein, Adi; Franz, Michael G.; Patel, Shaun P.; Kuzon, William M.; Urbanchek, Melanie G.

2015-01-01

Background Incisional hernias are a complication in 10% of all open abdominal operations and can result in significant morbidity. The purpose of this study is to determine if inhibiting abdominal muscle contraction influences incisional hernia formation during laparotomy healing. We hypothesize that reducing abdominal musculature deformation reduces incisional hernia occurrence and size. Study Design Using an established rat model for incisional hernia, a laparotomy through the linea alba was closed with one mid-incision, fast-absorbing suture. Three groups were compared: a SHAM group (SHAM; n = 6) received no laparotomies while the Saline Hernia (SH; n = 6) and Botox Hernia (BH; n = 6) groups were treated once with equal volume saline or Botulinum Toxin (Botox®, Allergan) before the incomplete laparotomy closure. On post-operative day 14, the abdominal wall was examined for herniation and adhesions and contractile forces were measured for abdominal wall muscles. Results No hernias developed in SHAM rats. Rostral hernias developed in all SH and BH rats. Caudal hernias developed in all SH rats, but in only 50% of the BH rats. Rostral hernias in the BH group were 35% shorter and 43% narrower compared to those in the SH group (p < 0.05). The BH group had weaker abdominal muscles compared to the SHAM and SH groups (p < 0.05). Conclusions In our rat model, partial paralysis of abdominal muscles reduces the number and size of incisional hernias. These results confirm abdominal wall muscle contractions play a significant role in the pathophysiology of incisional hernia formation. PMID:25817097

Effects of Material Properties on Bacterial Adhesion and Biofilm Formation.

PubMed

Song, F; Koo, H; Ren, D

2015-08-01

Adhesion of microbes, such as bacteria and fungi, to surfaces and the subsequent formation of biofilms cause multidrug-tolerant infections in humans and fouling of medical devices. To address these challenges, it is important to understand how material properties affect microbe-surface interactions and engineer better nonfouling materials. Here we review the recent progresses in this field and discuss the main challenges and opportunities. In particular, we focus on bacterial biofilms and review the effects of surface energy, charge, topography, and stiffness of substratum material on bacterial adhesion. We summarize how these surface properties influence oral biofilm formation, and we discuss the important findings from nondental systems that have potential applications in dental medicine. © International & American Associations for Dental Research 2015.

Visceral mobilization can lyse and prevent peritoneal adhesions in a rat model.

PubMed

Bove, Geoffrey M; Chapelle, Susan L

2012-01-01

Peritoneal adhesions are almost ubiquitous following surgery. Peritoneal adhesions can lead to bowel obstruction, digestive problems, infertility, and pain, resulting in many hospital readmissions. Many approaches have been used to prevent or treat adhesions, but none offer reliable results. A method that consistently prevented or treated adhesions would benefit many patients. We hypothesized that an anatomically-based visceral mobilization, designed to promote normal mobility of the abdominal contents, could manually lyse and prevent surgically-induced adhesions. Cecal and abdominal wall abrasion was used to induce adhesions in 3 groups of 10 rats (Control, Lysis, and Preventive). All rats were evaluated 7 days following surgery. On postoperative day 7, unsedated rats in the Lysis group were treated using visceral mobilization, consisting of digital palpation, efforts to manually lyse restrictions, and mobilization of their abdominal walls and viscera. This was followed by immediate post-mortem adhesion evaluation. The rats in the Preventive group were treated daily in a similar fashion, starting the day after surgery. Adhesions in the Control rats were evaluated 7 days after surgery without any visceral mobilization. The therapist could palpate adhesions between the cecum and other viscera or the abdominal wall. Adhesion severity and number of adhesions were significantly lower in the Preventive group compared to other groups. In the Lysis and Preventive groups there were clear signs of disrupted adhesions. These initial observations support visceral mobilization may have a role in the prevention and treatment of post-operative adhesions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evaluation of a new composite prosthesis for the repair of abdominal wall defects.

PubMed

Losi, Paola; Munaò, Antonella; Spiller, Dario; Briganti, Enrica; Martinelli, Ilaria; Scoccianti, Marco; Soldani, Giorgio

2007-10-01

The degree of integration of biomaterials used in the repair of abdominal wall defects seems to depend upon the structure of the prosthesis. The present investigation evaluates the behaviour in terms of adhesion formation and integration of a new composite prosthesis that could be employed in this clinical application. Full-thickness abdominal wall defects (7 x 5 cm) were created in 16 anaesthetized New Zealand white rabbits and the prosthesis were placed in direct contact with the visceral peritoneum during the experiment. The defects were repaired with a composite prosthesis or pure polypropylene mesh to establish two study groups (n = 8 each). The composite device was constituted by a polypropylene mesh physically attached to a poly(ether)urethane-polydimethylsiloxane laminar sheet. Animals were sacrificed 7, 14, 21 and 30 days after implant and prosthesis/surrounding tissue specimens subjected to light and electron microscopy. Firm adhesions were detected in the polypropylene implants, while they were not present in the composite implants. The excellent behaviour of the composite prosthesis shown in this study warrants further investigation on its use for the repair of abdominal wall defects when a prosthetic device needs to be placed in contact with the intestinal loops.

PAR-2 mediates increased inflammatory cell adhesion and neointima formation following vascular injury in the mouse.

PubMed

Tennant, Gail M; Wadsworth, Roger M; Kennedy, Simon

2008-05-01

Activation of PAR-2 in the vasculature affects vascular tone and adhesion of leukocytes to the endothelium. Since adhesion of leukocytes is increased following vascular injury and is important in determining the extent of neointima formation, we hypothesised that mice lacking PAR-2 may have reduced neointima formation following vascular injury. PAR-2 activating peptides and trypsin induced endothelium-dependent relaxation of mouse carotid artery which was absent in the knockout mouse. Lack of a PAR-2 receptor did not affect lymphocyte adhesion under basal conditions, but reduced the contractile response produced by lymphocytes. Twenty-eight days after denuding injury, vessel contraction to lymphocytes was reduced in both strains while lymphocyte adhesion was significantly greater in PAR-2(+/+) mice compared to the PAR-2 knockout mice. Neointimal area was markedly reduced in the PAR-2 knockout mouse. Our data show that PAR-2 modulates inflammatory cell adhesion when stimulated and in mice lacking the PAR-2 receptor, adhesion to injured vessels is reduced with a consequent reduction in neointima formation.

Administration of Intravenous Inf liximab for Prevention of Peritoneal Adhesions Formation in Rats.

PubMed

Nikeghbalian, Saman; Vafaei, Homeira; Moradian, Farid; Kazemi, Kourosh; Tanideh, Nader; Shayan, Leila; Nikeghbalian, Zahra

2015-07-01

To investigate the effects of intravenous infliximab in preventing the formation of peritoneal adhesions in an animal model of rat. This was an experimental study being performed in animal laboratory of Shiraz University of Medical Sciences during 2012. Sixty albino rats were randomly assigned in to three groups by Random Design Method. The first group received single infliximab injection (n=20), the second one received double infliximab injection (n=20) and the third received nothing (n=20), after receiving intra-peritoneal injection of talc for induction of peritoneal adhesions. All the animals were sacrificed after 6 weeks and the peritoneal adhesions were evaluated according to Nair classification. We observed that the mean adhesion grade was lower in those who received double dose of infliximib when compared to single dose and controls. However the difference did not reach a significant value (p=0.178). The grade of peritoneal adhesion was also comparable between the three study groups (p=0.103). The mean number of 1st WBC count was also comparable between three study groups (p=0.382). We observed that 2nd WBC count was also comparable between two study groups (p=0.317). Administration of intravenous infliximab after intraabdominal surgicalprocedures would not prevent the formation of peritoneal adhesions in animal model of albino rat.

Culinary Medicine-Jalebi Adhesions.

PubMed

Kapoor, Vinay K

2016-02-01

Culinary terms have been used to describe anatomy (bean-shaped kidneys), pathology (strawberry gall bladder), clinical signs (café-au-lait spots), radiological images (sausage-shaped pancreas), etc. While Indian cuisine is popular all over the world, no Indian dish finds mention in medical terminology. In intra-abdominal adhesions, sometimes, the intestinal loops are so densely adherent that it is difficult to make out proximal from distal and it is impossible to separate them without injuring the bowel resulting in spill of contents-resection is the only option (Fig. 1). Jalebi, an Indian dessert, has a single long tubular strip of fried batter filled with sugary syrup so intertwined that it is impossible to discern its ends; if broken, the syrup spills out-the best way to relish it is to chew the whole piece (Fig. 2). Because of these similarities between them, I propose to name dense intra-abdominal adhesions as 'jalebi adhesions.'

Prevention of Intraabdominal Adhesions: An Experimental Study Using Mitomycin-C and 4% Icodextrin.

PubMed

Urkan, Murat; Özerhan, İsmail Hakkı; Ünlü, Aytekin; Can, Mehmet Fatih; Öztürk, Erkan; Günal, Armağan; Yağcı, Gökhan

2017-01-01

Intraabdominal adhesions remain a significant cause of morbidity and mortality. Moreover, intraabdominal adhesions can develop in more than 50% of abdominal operations. We compared the anti-adhesive effects of two different agents on postoperative adhesion formation in a cecal abrasion model. Experimental animal study. Forty Wistar albino type female rats were anesthetized and underwent laparotomy. Study groups comprised Sham, Control, Mitomycin-C, 4% Icodextrin, and Mitomycin-C +4% Icodextrin groups. Macroscopic and histopathological evaluations of adhesions were performed. The frequencies of moderate and severe adhesions were significantly higher in the control group than the other groups. The mitomycin-C and Mitomycin-C +4% Icodextrin groups were associated with significantly lower adhesion scores compared to the control group and 4% Icodextrin group scores (p=0.002 and p=0.008, respectively). The adhesion scores of the Mitomycin-C group were also significantly lower than those of the 4% Icodextrin group (p=0.008). Despite its potential for bone marrow toxicity, Mitomycin-C seems to effectively prevent adhesions. Further studies that prove an acceptable safety profile relating to this promising anti-adhesive agent are required before moving into clinical trials.

Effects of sodium hyaluronate on tendon healing and adhesion formation in horses.

PubMed

Gaughan, E M; Nixon, A J; Krook, L P; Yeager, A E; Mann, K A; Mohammed, H; Bartel, D L

1991-05-01

Sodium hyaluronate reduces adhesions after tendon repair in rodents and dogs, and has been used in limited clinical trials in people. To evaluate its effect on tendon healing and adhesion formation in horses and to compare these effects with those of a compound of similar visco-elastic properties, a study was performed in horses, using a model of collagenase injection in the flexor tendons within the digital sheath. Eight clinically normal horses were randomly allotted to 2 groups. Adhesion formation between the deep digital flexor tendon and the tendon sheath at the pastern region was induced in the forelimbs of all horses. Using tenoscopic control, a 20-gauge needle was inserted into the deep digital flexor tendon of horses under general anesthesia and 0.2 ml of collagenase (2.5 mg/ml) was injected. The procedure was repeated proximally at 2 other sites, spaced 1.5 cm apart. A biopsy forceps was introduced, and a 5-mm tendon defect was created at each injection site. Group-A horses had 120 mg of sodium hyaluronate (NaHA) gel injected into the tendon sheath of one limb. Group-B horses had methylcellulose gel injected at the same sites. The contralateral limbs of horses in both groups served as surgical, but noninjected, controls. Horses were euthanatized after 8 weeks of stall rest. Ultrasonographic evaluation revealed improved tendon healing after NaHa injection, but no difference in peritendinous adhesion formation. Tendon sheath fluid volume and hyaluronic acid (HA) content were greater in NaHA-treated limbs. Gross pathologic examination revealed considerably fewer and smaller adhesions when limbs were treated with NaHA. However, significant difference in pull-out strengths was not evident between NaHA-treated and control limbs. Histologically, the deep digital flexor tendon from the NaHA-treated limbs had reduced inflammatory cell infiltration, improved tendon structure, and less intratendinous hemorrhage. Treatment with methylcullulose had no significant

[The mechanisms of formation of liver injuries associated with the blunt abdominal trauma].

PubMed

Pigolkin, Iu I; Dubrovina, I A; Dubrovin, I A

2012-01-01

The mechanisms of liver damage associated with the blunt abdominal trauma are considered based on the analysis of the literature publications. The general characteristic of these mechanisms and the processes underlying the development of liver injuries is presented. It is argued that the mechanisms underlying the formation of damages to the liver differ depending on the form of the traumatic impact, the injurious factor, and the processes leading to the destruction of the hepatic tissue. The main forms of traumatic impact in the case of a blunt abdominal trauma include the strike (blow), pressure, and concussion of the organ while the major traumatic factors are deformation, displacement, and "shock-resistant effects". The mechanisms underlying tissue destruction are compression and stretching. These two mechanisms are responsible for the formation of different variants of liver destruction. The results of the study suggest the necessity of the search for other mechanisms of degradation of the hepatic tissue following a blunt abdominal trauma for the improvement of forensic medical diagnostics of its cause and the underlying mechanism.

Liquid Paraffin vs Hyaluronic Acid in Preventing Intraperitoneal Adhesions.

PubMed

Kataria, Hanish; Singh, Vinod Prem

2017-12-01

Adhesion formation after abdominal and pelvic operations remains a challenging problem. Role of adjuvant barriers have been studied but there is no comparative study between liquid paraffin and hyaluronic acid as a barrier method. Hence, we planned to compare the effectiveness of 0.4 % hyaluronic acid and liquid paraffin in the prevention of postoperative intraperitoneal adhesions in rats. This prospective, randomized and controlled study was conducted in 60 adult Wistar albino rats. Surgical trauma by caecal abrasion and 1 g talcum powder was used in the rat model to induce adhesion formation. After trauma, 3 ml normal saline was instilled in the peritoneal cavity in control group ( n  = 20), 3 ml liquid paraffin was instilled in experimental group A ( n  = 20) and 3 ml 0.4 % hyaluronic acid was instilled in experimental group B ( n  = 20). Two weeks after laparotomy, repeat laparotomy was performed and the adhesions were scored according to Zuhlke classification. Liquid paraffin and hyaluronic acid both reduce the extent and grade of adhesions both macroscopically ( p  = 0.018, p  = 0.017) and microscopically ( p  = 0.019, p  = 0.019) respectively. Although there was significant reduction in adhesions by hyaluronic acid at certain specific sites as compared with liquid paraffin, its overall effectiveness in preventing postoperative intraperitoneal adhesions is not significantly different from liquid paraffin ( p  = 0.092, p  = 0.193) respectively. The presence of liquid paraffin and hyaluronic acid in the peritoneal cavity reduce postoperative intraperitoneal adhesions significantly in rats. However, there is no overall significant difference in the effectiveness of two groups. Dosage and safety of these chemicals in human beings remains to be established.

Modeling the formation of cell-matrix adhesions on a single 3D matrix fiber.

PubMed

Escribano, J; Sánchez, M T; García-Aznar, J M

2015-11-07

Cell-matrix adhesions are crucial in different biological processes like tissue morphogenesis, cell motility, and extracellular matrix remodeling. These interactions that link cell cytoskeleton and matrix fibers are built through protein clutches, generally known as adhesion complexes. The adhesion formation process has been deeply studied in two-dimensional (2D) cases; however, the knowledge is limited for three-dimensional (3D) cases. In this work, we simulate different local extracellular matrix properties in order to unravel the fundamental mechanisms that regulate the formation of cell-matrix adhesions in 3D. We aim to study the mechanical interaction of these biological structures through a three dimensional discrete approach, reproducing the transmission pattern force between the cytoskeleton and a single extracellular matrix fiber. This numerical model provides a discrete analysis of the proteins involved including spatial distribution, interaction between them, and study of the different phenomena, such as protein clutches unbinding or protein unfolding. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microsurgical principles and postoperative adhesions: lessons from the past.

PubMed

Gomel, Victor; Koninckx, Philippe R

2016-10-01

"Microsurgery" is a set of principles developed to improve fertility surgery outcomes. These principles were developed progressively based on common sense and available evidence, under control of clinical feedback obtained with the use of second-look laparoscopy. Fertility outcome was the end point; significant improvement in fertility rates validated the concept clinically. Postoperative adhesion formation being a major cause of failure in fertility surgery, the concept of microsurgery predominantly addresses prevention of postoperative adhesions. In this concept, magnification with a microscope or laparoscope plays a minor role as technical facilitator. Not surprisingly, the principles to prevent adhesion formation are strikingly similar to our actual understanding: gentle tissue handling, avoiding desiccation, irrigation at room temperature, shielding abdominal contents from ambient air, meticulous hemostasis and lavage, avoiding foreign body contamination and infection, administration of dexamethasone postoperatively, and even the concept of keeping denuded areas separated by temporary adnexal or ovarian suspension. The actual concepts of peritoneal conditioning during surgery and use of dexamethasone and a barrier at the end of surgery thus confirm without exception the tenets of microsurgery. Although recent research helped to clarify the pathophysiology of adhesion formation, refined its prevention and the relative importance of each factor, the clinical end point of improvement of fertility rates remains demonstrated for only the microsurgical tenets as a whole. In conclusion, the principles of microsurgery remain fully valid as the cornerstones of reproductive microsurgery, whether performed by means of open access or laparoscopy. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Post-operative ovarian adhesion formation after ovarian drilling: a randomized study comparing conventional laparoscopy and transvaginal hydrolaparoscopy.

PubMed

Giampaolino, Pierluigi; Morra, Ilaria; Tommaselli, Giovanni Antonio; Di Carlo, Costantino; Nappi, Carmine; Bifulco, Giuseppe

2016-10-01

To compare conventional laparoscopic ovarian drilling (LOD) with transvaginal hydrolaparoscopy (THL) ovarian drilling in terms of ovarian adhesion formation, evaluated using office THL during follow-up in CC-resistant anovulatory patients affected by PCOS. Prospective randomized study on 246 CC-resistant women with PCOS. The patients enrolled were divided into two groups, 123 were scheduled to undergo LOD and 123 to undergo THL ovarian drilling. Six months after the procedure all patients were offered office transvaginal hydrolaparoscopy (THL) follow-up, under local anesthesia to evaluate adhesion formation. Duration of the procedure was significantly shorter in the THL group in comparison with LOD group (p < 0.0001). No intra- or post-operative complication was observed in any of the patients in both groups. Post-operative THL follow-up after 6 months showed that 15 (15.5 %) patients in the THL group and 73 (70.2 %) in the LOD group showed the presence of ovarian adhesion. This difference was highly significant with a p value <0.0001 and a relative risk of 0.22 [95 % IC 0.133-0.350]. This study seems to indicate that THL ovarian drilling may reduce the risk of ovarian adhesion formation and could be used as a safe and effective option to reduce ovarian adhesion formation in patients undergoing ovarian drilling.

Diagnosis and surgical management of abdominal cocoon: results from 12 cases.

PubMed

Liu, Hai-yan; Wang, Yong-sheng; Yang, Wan-guang; Yin, Sheng-lu; Pei, Hui; Sun, Tong-wen; Wang, Lexin

2009-01-01

This study was designed to describe the characteristics, diagnostic and therapeutic methods of abdominal cocoon. Twelve patients with abdominal cocoon were surgically treated. The clinical findings from these patients were analyzed. All patients presented with acute complete intestinal obstruction, and 10 had a previous history of abdominal mass. In nine patients, the whole or part of the small intestines were covered by an ash gray, dense and tough fibrous membrane. The capsule was surgically excised, and the adhesion was released. Partial resection of the small intestines was performed. In the other three patients, the small intestines were only partially covered by a membrane, and there was an extensive adhesion of intestinal tract, forming a large mass which could not be relieved by surgical lysis. Intestinal tube was put in, and fistulation procedures were performed. All patients recovered fully after the surgery. There are four types of surgical findings in abdominal cocoon. The most common type is that the small intestines are fully covered by a thick white membrane, causing intestinal obstruction. Surgical excision of the membrane and the release of adhesion is the treatment of choice.

Effects of magnolol and honokiol on adhesion, yeast-hyphal transition, and formation of biofilm by Candida albicans.

PubMed

Sun, Lingmei; Liao, Kai; Wang, Dayong

2015-01-01

The first step in infection by Candida albicans is adhesion to host cells or implanted medical devices and this followed by hyphal growth and biofilm formation. Yeast-to-hyphal transition has long been identified as a key factor in fungal virulence. Following biofilm formation, C. albicans is usually less sensitive or insensitive to antifungals. Therefore, development of new antifungals with inhibitory action on adhesion, yeast-hyphal transition and biofilm formation by C. albicans is very necessary. The effects of magnolol and honokiol on hypha growth were investigated using different induction media. Their inhibitory effects were determined using the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5- carboxanilide assay, and biofilm thickness and viability were observed by a confocal scanning laser microscope. Mammalian cells were used in adhesion assays. Genes related to hyphae development and cell adhesions were analyzed by real-time reverse transcription-polymerase chain reaction. The exogenous cyclic adenosine monophosphate was used to determine the mechanisms of action of magnolol and honokiol. Caenorhabditis elegans was used as an in vivo model to estimate the antifungal activities of magnolol and honokiol. Magnolol and honokiol inhibited adhesion, the transition from yeast to hypha, and biofilm formation by C. albicans through the Ras1-cAMP-Efg1 pathway. Moreover, magnolol and honokiol prolonged the survival of nematodes infected by C. albicans. Magnolol and honokiol have potential inhibitory effects against biofilm formation by C. albicans. This study provides useful information towards the development of new strategies to reduce the incidence of C. albicans biofilm-associated infection.

Implanting intra-abdominal radiotransmitters with external whip antennas in ducks

USGS Publications Warehouse

Korschgen, C.E.; Kenow, K.P.; Gendron-Fitzpatrick, A.; Green, W.L.; Dein, F.J.

1996-01-01

We developed and evaluated a surgical procedure for implanting intra-abdominal radiotransmitters with external whip antennas in captive mallards (Anas platyrhynchos). Transmitters were implanted in the abdominal cavity and the antennas exited through the caudal abdominal wall and skin. Birds with implanted transmitters developed mild to moderate localized air sac reactions. These reactions involved adhesions of the right anterior abdominal air sac to the liver with contractions around the transmitters and antenna catheters. The adhesions were reinforced by a proliferation of connective tissue and lined by multinucleated giant cells (foreign body reaction). Casual observation indicated that neither behavior nor activity of the birds was altered by the histological reaction to the transmitter implant. No increase in systemic lesions (particularly liver or kidney) could be correlated with the histological reactions. Our evaluations indicate that the procedure is a reliable method for radiomarking ducks and the technique has been successfully used in 2 field studies.

Bisphosphonates enhance bacterial adhesion and biofilm formation on bone hydroxyapatite.

PubMed

Kos, Marcin; Junka, Adam; Smutnicka, Danuta; Szymczyk, Patrycja; Gluza, Karolina; Bartoszewicz, Marzenna

2015-07-01

Because of the suspicion that bisphosphonates enhance bacterial colonization, this study evaluated adhesion and biofilm formation by Streptococcus mutans 25175, Staphylococcus aureus 6538, and Pseudomonas aeruginosa 14454 reference strains on hydroxyapatite coated with clodronate, pamidronate, or zoledronate. Bacterial strains were cultured on bisphosphonate-coated and noncoated hydroxyapatite discs. After incubation, nonadhered bacteria were removed by centrifugation. Biofilm formation was confirmed by scanning electron microscopy. Bacterial colonization was estimated using quantitative cultures compared by means with Kruskal-Wallis and post-hoc Student-Newman-Keuls tests. Modeling of the interactions between bisphosphonates and hydroxyapatite was performed using the Density Functional Theory method. Bacterial colonization of the hydroxyapatite discs was significantly higher for all tested strains in the presence of bisphosphonates vs. Adherence in the presence of pamidronate was higher than with other bisphosphonates. Density Functional Theory analysis showed that the protonated amine group of pamidronate, which are not present in clodronate or zoledronate, forms two additional hydrogen bonds with hydroxyapatite. Moreover, the reactive cationic amino group of pamidronate may attract bacteria by direct electrostatic interaction. Increased bacterial adhesion and biofilm formation can promote osteomyelitis, cause failure of dental implants or bisphosphonate-coated joint prostheses, and complicate bone surgery in patients on bisphosphonates. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Abdominal-B and caudal inhibit the formation of specific neuroblasts in the Drosophila tail region

PubMed Central

Birkholz, Oliver; Vef, Olaf; Rogulja-Ortmann, Ana; Berger, Christian; Technau, Gerhard M.

2013-01-01

The central nervous system of Drosophila melanogaster consists of fused segmental units (neuromeres), each generated by a characteristic number of neural stem cells (neuroblasts). In the embryo, thoracic and anterior abdominal neuromeres are almost equally sized and formed by repetitive sets of neuroblasts, whereas the terminal abdominal neuromeres are generated by significantly smaller populations of progenitor cells. Here we investigated the role of the Hox gene Abdominal-B in shaping the terminal neuromeres. We show that the regulatory isoform of Abdominal-B (Abd-B.r) not only confers abdominal fate to specific neuroblasts (e.g. NB6-4) and regulates programmed cell death of several progeny cells within certain neuroblast lineages (e.g. NB3-3) in parasegment 14, but also inhibits the formation of a specific set of neuroblasts in parasegment 15 (including NB7-3). We further show that Abd-B.r requires cooperation of the ParaHox gene caudal to unfold its full competence concerning neuroblast inhibition and specification. Thus, our findings demonstrate that combined action of Abdominal-B and caudal contributes to the size and composition of the terminal neuromeres by regulating both the number and lineages of specific neuroblasts. PMID:23903193

Abdominal binders may reduce pain and improve physical function after major abdominal surgery - a systematic review.

PubMed

Rothman, Josephine Philip; Gunnarsson, Ulf; Bisgaard, Thue

2014-11-01

Evidence for the effect of post-operative abdominal binders on post-operative pain, seroma formation, physical function, pulmonary function and increased intra-abdominal pressure among patients after surgery remains largely un-investigated. A systematic review was conducted. The PubMed, EMBASE and Cochrane databases were searched for studies on the use of abdominal binders after abdominal surgery or abdominoplasty. All types of clinical studies were included. Two independent assessors evaluated the scientific quality of the studies. The primary outcomes were pain, seroma formation and physical function. A total of 50 publications were identified; 42 publications were excluded leaving eight publications counting a total of 578 patients for analysis. Generally, the scientific quality of the studies was poor. Use of abdominal binder revealed a non-significant tendency to reduce seroma formation after laparoscopic ventral herniotomy and a non-significant reduction in pain. Physical function was improved, whereas evidence supports a beneficial effect on psychological distress after open abdominal surgery. Evidence also supports that intra-abdominal pressure increases with the use of abdominal binders. Reduction of pulmonary function during use of abdominal binders has not been revealed. Abdominal binders reduce post-operative psychological distress, but their effect on post-operative pain after laparotomy and seroma formation after ventral hernia repair remains unclear. Due to the sparse evidence and poor quality of the literature, solid conclusions may be difficult to make, and procedure-specific, high-quality randomised clinical trials are warranted.

Effects of Magnolol and Honokiol on Adhesion, Yeast-Hyphal Transition, and Formation of Biofilm by Candida albicans

PubMed Central

Sun, Lingmei; Liao, Kai; Wang, Dayong

2015-01-01

Background The first step in infection by Candida albicans is adhesion to host cells or implanted medical devices and this followed by hyphal growth and biofilm formation. Yeast-to-hyphal transition has long been identified as a key factor in fungal virulence. Following biofilm formation, C. albicans is usually less sensitive or insensitive to antifungals. Therefore, development of new antifungals with inhibitory action on adhesion, yeast-hyphal transition and biofilm formation by C. albicans is very necessary. Methods The effects of magnolol and honokiol on hypha growth were investigated using different induction media. Their inhibitory effects were determined using the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5- carboxanilide assay, and biofilm thickness and viability were observed by a confocal scanning laser microscope. Mammalian cells were used in adhesion assays. Genes related to hyphae development and cell adhesions were analyzed by real-time reverse transcription-polymerase chain reaction. The exogenous cyclic adenosine monophosphate was used to determine the mechanisms of action of magnolol and honokiol. Caenorhabditis elegans was used as an in vivo model to estimate the antifungal activities of magnolol and honokiol. Results and conclusions Magnolol and honokiol inhibited adhesion, the transition from yeast to hypha, and biofilm formation by C. albicans through the Ras1-cAMP-Efg1 pathway. Moreover, magnolol and honokiol prolonged the survival of nematodes infected by C. albicans. Magnolol and honokiol have potential inhibitory effects against biofilm formation by C. albicans. General Significance This study provides useful information towards the development of new strategies to reduce the incidence of C. albicans biofilm-associated infection. PMID:25710475

Continuous-infusion local anesthetic pain pump use and seroma formation with abdominal procedures: is there a correlation?

PubMed

Smith, Melissa M; Hovsepian, Raffi V; Markarian, Mark K; Degelia, Amber L; Paul, Malcolm D; Evans, Gregory R D; Wirth, Garrett A

2008-11-01

Seroma formation is the most commonly occurring complication in plastic surgery abdominal procedures. Continuous local anesthetic pain pump delivery systems are often used to decrease postoperative pain. An unreported concern with use of these devices in abdominal procedures is the effect of continuous fluid infiltration of the surgical site and a possible increase in the incidence of seroma formation. The authors performed a retrospective chart review to evaluate all patients (n = 159) who underwent abdominal procedures (abdominoplasty, panniculectomy, and transverse rectus abdominis myocutaneous flap harvest) over a 3-year period. Patient charts were evaluated for sex, age, body mass index, procedure performed, surgeon, operation length, pain pump use, postoperative seroma formation, and any complications. In cases with pain pump use, catheter placement location, anesthetic medication and strength, continuous-infusion rate, and duration of pain pump use were also reviewed. If a postoperative seroma formation was identified, treatment and outcomes were also recorded. The overall seroma formation rate was 11.3 percent (18 of 159 patients). Other complications occurred at a rate of 2.5 percent (four of 159). The incidence of seroma was 11.0 percent (11 of 100) in patients with pain pump use versus 11.9 percent (7 of 59) in those who did not use a pain pump. There was no statistically significant difference (p = 0.9) in the incidence of seroma formation between those who did and did not use a pain pump device. There was no correlation between increased rate of seroma formation and use of a continuous-infusion local anesthetic pain pump system in our patient population.

Effect of functional monomers in all-in-one adhesive systems on formation of enamel/dentin acid-base resistant zone.

PubMed

Nikaido, Toru; Ichikawa, Chiaki; Li, Na; Takagaki, Tomohiro; Sadr, Alireza; Yoshida, Yasuhiro; Suzuki, Kazuomi; Tagami, Junji

2011-01-01

This study aimed at evaluating the effect of functional monomers in all-in-one adhesive systems on formation of acid-base resistant zone (ABRZ) in enamel and dentin. Experimental adhesive systems containing one of three functional monomers; MDP, 3D-SR and 4-META were applied to enamel or dentin surface and light-cured. A universal resin composite was then placed. The specimens were subjected to a demineralizing solution (pH 4.5) and 5% NaClO for acid-base challenge and then observed by SEM. The ABRZ was clearly observed in both enamel and dentin interfaces. However, enamel ABRZ was thinner than dentin ABRZ in all adhesives. Morphology of the ABRZ was different between enamel and dentin, and also among the adhesives. Funnel-shaped erosion was observed only in the enamel specimen with the 4-META adhesive. The formation of enamel/dentin ABRZ was confirmed in all adhesives, but the morphology was influenced by the functional monomers.

Effect of honey versus intergel in intraperitoneal adhesion prevention and colonic anastomotic healing: a randomized controlled study in rats.

PubMed

Saber, Aly

2010-01-01

Intra-abdominal adhesion formation and reformation after surgery are still an unavoidable event in spite of modern surgical techniques and are a cause of significant morbidity, resulting in infertility, pain and intestinal obstruction. To investigate the effect of honey in adhesion prevention and colonic anastomotic healing in rats. In the present study, 75 male Sprague-Dawley rats were used and divided into 3 groups for study: [25 rats for each], the intergel, honey and control groups. After the scheduled two-week's post-operative period, all survived rats were reopened for second-look laparotomy to detect the following parameters: a - adhesion, b - manometric study, c - histopathological study. The author found that the total adhesion score, the manometric values and the histopathological study among the three studied groups showed statistically significant difference and in favor of the honey-treated rats. Honey surpasses the intergel for the healing power and adhesion prevention. Copyright 2009 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Effects of membrane deformability and bond formation/dissociation rates on adhesion dynamics of a spherical capsule in shear flow.

PubMed

Zhang, Ziying; Du, Jun; Wei, Zhengying; Wang, Zhen; Li, Minghui

2018-02-01

Cellular adhesion plays a critical role in biological systems and biomedical applications. Cell deformation and biophysical properties of adhesion molecules are of significance for the adhesion behavior. In the present work, dynamic adhesion of a deformable capsule to a planar substrate, in a linear shear flow, is numerically simulated to investigate the combined influence of membrane deformability (quantified by the capillary number) and bond formation/dissociation rates on the adhesion behavior. The computational model is based on the immersed boundary-lattice Boltzmann method for the capsule-fluid interaction and a probabilistic adhesion model for the capsule-substrate interaction. Three distinct adhesion states, detachment, rolling adhesion and firm adhesion, are identified and presented in a state diagram as a function of capillary number and bond dissociation rate. The impact of bond formation rate on the state diagram is further investigated. Results show that the critical bond dissociation rate for the transition of rolling or firm adhesion to detachment is strongly related to the capsule deformability. At the rolling-adhesion state, smaller off rates are needed for larger capillary number to increase the rolling velocity and detach the capsule. In contrast, the critical off rate for firm-to-detach transition slightly increases with the capillary number. With smaller on rate, the effect of capsule deformability on the critical off rates is more pronounced and capsules with moderate deformability are prone to detach by the shear flow. Further increasing of on rate leads to large expansion of both rolling-adhesion and firm-adhesion regions. Even capsules with relatively large deformability can maintain stable rolling adhesion at certain off rate.

Shewanella putrefaciens Adhesion and Biofilm Formation on Food Processing Surfaces

PubMed Central

Bagge, Dorthe; Hjelm, Mette; Johansen, Charlotte; Huber, Ingrid; Gram, Lone

2001-01-01

Laboratory model systems were developed for studying Shewanella putrefaciens adhesion and biofilm formation under batch and flow conditions. S. putrefaciens plays a major role in food spoilage and may cause microbially induced corrosion on steel surfaces. S. putrefaciens bacteria suspended in buffer adhered readily to stainless steel surfaces. Maximum numbers of adherent bacteria per square centimeter were reached in 8 h at 25°C and reflected the cell density in suspension. Numbers of adhering bacteria from a suspension containing 108 CFU/ml were much lower in a laminar flow system (modified Robbins device) (reaching 102 CFU/cm2) than in a batch system (reaching 107 CFU/cm2), and maximum numbers were reached after 24 h. When nutrients were supplied, S. putrefaciens grew in biofilms with layers of bacteria. The rate of biofilm formation and the thickness of the film were not dependent on the availability of carbohydrate (lactate or glucose) or on iron starvation. The number of S. putrefaciens bacteria on the surface was partly influenced by the presence of other bacteria (Pseudomonas fluorescens) which reduced the numbers of S. putrefaciens bacteria in the biofilm. Numbers of bacteria on the surface must be quantified to evaluate the influence of environmental factors on adhesion and biofilm formation. We used a combination of fluorescence microscopy (4′,6′-diamidino-2-phenylindole staining and in situ hybridization, for mixed-culture studies), ultrasonic removal of bacteria from surfaces, and indirect conductometry and found this combination sufficient to quantify bacteria on surfaces. PMID:11319118

Risk of Late-Onset Adhesions and Incisional Hernia Repairs after Surgery

PubMed Central

Bensley, Rodney P; Schermerhorn, Marc L; Hurks, Rob; Sachs, Teviah; Boyd, Christopher A; O’Malley, A James; Cotterill, Philip; Landon, Bruce E

2013-01-01

BACKGROUND Long-term adhesion-related complications and incisional hernias after abdominal surgery are common and costly. There are few data on the risk of these complications after different abdominal operations. STUDY DESIGN We identified Medicare beneficiaries who underwent endovascular repair of an abdominal aortic aneurysm from 2001–2008 who presumably are not at risk for laparotomy-related complications. We identified all laparoscopic and open operations involving the abdomen, pelvis, or retroperitoneum and categorized them into 5 groups according to invasiveness. We then identified laparotomy-related complications for up to 5 years after the index operation and compared these with the baseline rate of complications in a control group of patients who did not undergo an abdominal operation. RESULTS We studied 85,663 patients, 7,513 (8.8%) of which underwent a laparotomy, including 2,783 major abdominal operations, 709 minor abdominal operations, 963 ventral hernia repairs, 493 retroperitoneal/pelvic operations, and 2,565 laparoscopic operations. Mean age was 76.7 years and 82.0% were male. Major abdominal operations carried the highest risk for adhesion-related complications (14.3% and 25.0% at 2 and 5 years compared with 4.0% and 7.8% for the control group; p < 0.001) and incisional hernias (7.8% and 12.0% compared with 0.6% and 1.2% for the control group; p < 0.001). Laparoscopic operations (4.6% and 10.7% for adhesions, 1.9% and 3.2% for incisional hernias) carried the lowest risk. CONCLUSIONS Late-onset laparotomy-related complications are frequent and their risk extends through 5 years beyond the perioperative period. With the advancement and expansion of laparoscopic techniques and its attendant lower risk for long-term complications, these results can alter the risk-to-benefit profile of various types of abdominal operations and can also strengthen the rationale for additional development of laparoscopic approaches to abdominal operations. PMID

Humidity-enhanced wet adhesion on insect-inspired fibrillar adhesive pads

PubMed Central

Xue, Longjian; Kovalev, Alexander; Eichler-Volf, Anna; Steinhart, Martin; Gorb, Stanislav N.

2015-01-01

Many insect species reversibly adhere to surfaces by combining contact splitting (contact formation via fibrillar contact elements) and wet adhesion (supply of liquid secretion via pores in the insects’ feet). Here, we fabricate insect-inspired fibrillar pads for wet adhesion containing continuous pore systems through which liquid is supplied to the contact interfaces. Synergistic interaction of capillarity and humidity-induced pad softening increases the pull-off force and the work of adhesion by two orders of magnitude. This increase and the independence of pull-off force on the applied load are caused by the capillarity-supported formation of solid–solid contact between pad and the surface. Solid–solid contact dominates adhesion at high humidity and capillarity at low humidity. At low humidity, the work of adhesion strongly depends on the amount of liquid deposited on the surface and, therefore, on contact duration. These results may pave the way for the design of insect-inspired adhesive pads. PMID:25791574

Potential risk of port-site adhesions in patients after laparoscopic myomectomy using radially expanding trocars.

PubMed

Kumakiri, Jun; Kikuchi, Iwaho; Kitade, Mari; Jinushi, Makoto; Shinjyo, Azusa; Takeda, Satoru

2015-01-01

To investigate the incidence of port-site adhesions following use of radially expanding trocars (RETs) at laparoscopic myomectomy by observation via second-look laparoscopy (SLL). In a retrospective study, data from patients who underwent SLL after laparoscopic myomectomy between January 2007 and June 2012 at Juntendo University Hospital, Tokyo, were assessed for the incidence of port-site adhesions forming below RET incisional scars when fascial and peritoneal defects had not been closed. During the study period, 554 patients underwent SLL, and 2176 incisional scars were examined. Adhesions were detected in 15 patients (2.8%); thus, the incidence of port-site adhesions under scars was 0.7% (15/2176). Among these 15 patients, the wounds with adhesions were located as follows: 6 (1.1%) under the umbilical scar, 5 (0.9%) under the right lower abdominal scar, 2 (0.4%) under the left upper abdominal scar, and 2 (0.4%) under the left lower abdominal scar. According to multiple regression analysis, the duration of laparoscopic myomectomy was positively associated with port-site adhesions (odds ratio, 1.79; 95% confidence interval, 1.09-2.94; P=0.02). The present data suggest that the incidence of port-site hernias and adhesions under RET incisional scars is low despite the non-closure of fascial and peritoneal defects. Copyright © 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Vitamin E Inhibits Abdominal Aortic Aneurysm Formation in Angiotensin II–Infused Apolipoprotein E–Deficient Mice

PubMed Central

Gavrila, Dan; Li, Wei Gen; McCormick, Michael L.; Thomas, Manesh; Daugherty, Alan; Cassis, Lisa A.; Miller, Francis J.; Oberley, Larry W.; Dellsperger, Kevin C.; Weintraub, Neal L.

2014-01-01

Background Abdominal aortic aneurysms (AAAs) in humans are associated with locally increased oxidative stress and activity of NADPH oxidase. We investigated the hypothesis that vitamin E, an antioxidant with documented efficacy in mice, can attenuate AAA formation during angiotensin II (Ang II) infusion in apolipoprotein E–deficient mice. Methods and Results Six-month-old male apolipoprotein E–deficient mice were infused with Ang II at 1000 ng/kg per minute for 4 weeks via osmotic minipumps while consuming either a regular diet or a diet enriched with vitamin E (2 IU/g of diet). After 4 weeks, abdominal aortic weight and maximal diameter were determined, and aortic tissues were sectioned and examined using biochemical and histological techniques. Vitamin E attenuated formation of AAA, decreasing maximal aortic diameter by 24% and abdominal aortic weight by 34% (P<0.05, respectively). Importantly, animals treated with vitamin E showed a 44% reduction in the combined end point of fatal+nonfatal aortic rupture (P<0.05). Vitamin E also decreased aortic 8-isoprostane content (a marker of oxidative stress) and reduced both aortic macrophage infiltration and osteopontin expression (P<0.05, respectively). Vitamin E treatment had no significant effect on the extent of aortic root atherosclerosis, activation of matrix metalloproteinases 2 or 9, serum lipid profile, or systolic blood pressure. Conclusions Vitamin E ameliorates AAAs and reduces the combined end point of fatal+nonfatal aortic rupture in this animal model. These findings are consistent with the concept that oxidative stress plays a pivotal role in Ang II–driven AAA formation in hyperlipidemic mice. PMID:15933246

Recent Advances in Molecular Mechanisms of Abdominal Aortic Aneurysm Formation

PubMed Central

Annambhotla, Suman; Bourgeois, Sebastian; Wang, Xinwen; Lin, Peter H.; Yao, Qizhi; Chen, Changyi

2010-01-01

Abdominal Aortic Aneurysm (AAA) is an increasingly common clinical condition with fatal implications. It is associated with advanced age, male gender, cigarette smoking, atherosclerosis, hypertension, and genetic predisposition. Although significant evidence has emerged in the last decade, the molecular mechanisms of AAA formation remains poorly understood. Currently, the treatment for AAA remains primarily surgical with the lone innovation of endovascular therapy. With advance in the human genome, understanding precisely which molecules and genes mediate AAA development and blocking their activity at the molecular level could lead to important new discoveries and therapies. This review summarizes recent updates in molecular mechanisms of AAA formation including animal models, autoimmune components, infection, key molecules and cytokines, mechanical forces, genetics and pharmacotherapy. This review will be helpful to those who want to recognize the newest endeavors within the field and identify possible lines of investigation in AAA. PMID:18259804

Efficacy of surface-generated nitric oxide against Candida albicans adhesion and biofilm formation.

PubMed

Privett, Benjamin J; Nutz, Steven T; Schoenfisch, Mark H

2010-11-01

This report details the efficacy of nitric oxide (NO)-releasing xerogel surfaces composed of N-(6-aminohexyl)aminopropyl trimethoxysilane (AHAP3) and isobutyltrimethoxysilane (BTMOS) against Candida albicans adhesion, viability, and biofilm formation. A parallel plate flow cell assay was used to examine the effect of NO on planktonic fungal cells. Nitric oxide fluxes as low as 14 pmol cm(-2) s(-1) were sufficient to reduce fungal adhesion by ∼49% over the controls after 90 min. By utilizing a fluorescence live/dead assay and replicate plating, NO flux was determined to reduce fungal viability in a dose-dependent manner. The formation of C. albicans biofilms on NO-releasing xerogel-coated silicon rubber (SiR) coupons was impeded when compared to control (non-NO-releasing) and bare SiR surfaces. The synergistic efficacy of NO and silver sulfadiazine against adhered fungal cells and biofilms is reported with increased killing and biofilm inhibition over NO alone.

Risk of Essure microinsert abdominal migration: case report and review of literature

PubMed Central

Ricci, Giuseppe; Restaino, Stefano; Di Lorenzo, Giovanni; Fanfani, Francesco; Scrimin, Federica; Mangino, Francesco P

2014-01-01

Purpose To report a case of Essure microinsert abdominal migration and literature review. Methods A 41-year-old woman was counseled to undergo Essure sterilization. The procedure was hampered by the presence of endometrial cavity adhesions, obscuring left tubal ostium. By using microscissors the adhesions were progressively lysed. Since the procedure had become very painful, the patient required general anesthesia. Once adhesion lysis was completed, the tubal ostium was well visible. Both devices were then easily introduced into the fallopian tubes. At the end of the procedure, five coils were visible on the right side and five coils on the left side, as recommended. Results The 3-month hysterosalpingogram follow-up suspected abdominal migration of the left device. Laparoscopy confirmed the device displacement in the left lower abdominal quadrant. Both fallopian tubes and the uterus appeared normal. No signs of perforation were detected. The device was embedded into the omentum, but it was easily removed. Bilateral tubal sterilization was performed by bipolar coagulation. Conclusion There are only 13 cases, including the present, of Essure abdominal migration in the literature. In most cases, abdominal displacement of the microinsert is asymptomatic and does not induce tissue damage. However, in some cases, it may cause a severe adverse event, requiring major surgery. Therefore, removal of the migrated device should be performed as soon as possible. Moreover, during presterilization counseling, the patient should also be correctly informed about the risk of this rare but relevant complication, as well as about the surgical interventions that could be required to solve it. PMID:25484591

Cell Adhesion-dependent Serine 85 Phosphorylation of Paxillin Modulates Focal Adhesion Formation and Haptotactic Migration via Association with the C-terminal Tail Domain of Talin*

PubMed Central

Kwak, Tae Kyoung; Lee, Mi-Sook; Ryu, Jihye; Choi, Yoon-Ju; Kang, Minkyung; Jeong, Doyoung; Lee, Jung Weon

2012-01-01

Integrin-mediated adhesion to extracellular matrix proteins is dynamically regulated during morphological changes and cell migration. Upon cell adhesion, protein-protein interactions among molecules at focal adhesions (FAs) play major roles in the regulation of cell morphogenesis and migration. Although tyrosine phosphorylation of paxillin is critically involved in adhesion-mediated signaling, the significance of paxillin phosphorylation at Ser-85 and the mechanism by which it regulates cell migration remain unclear. In this study, we examined how Ser-85 phosphorylation of paxillin affects FA formation and cell migration. We found that paxillin phosphorylation at Ser-85 occurred during HeLa cell adhesion to collagen I and was concomitant with tyrosine phosphorylation of both focal adhesion kinase and talin. However, the non-phosphorylatable S85A mutant of paxillin impaired cell spreading, FA turnover, and migration toward collagen I but not toward serum. Furthermore, whereas the (presumably indirect) interaction between paxillin and the C-terminal tail of talin led to dynamic FAs at the cell boundary, S85A paxillin did not bind talin and caused stabilized FAs in the central region of cells. Together, these observations suggest that cell adhesion-dependent Ser-85 phosphorylation of paxillin is important for its interaction with talin and regulation of dynamic FAs and cell migration. PMID:22761432

Intestinal adhesion to the abdominal wall after skin closure with octylcyanoacrylate.

PubMed

Chaya, Miguel; Reyes-Cuervo, Humberto; Cruz, Vivian; Barroso, Gerardo; Garcia-León, Fernando

2004-08-01

Octylcyanoacrylate tissue adhesive glue is a wound closure device recently approved by the U.S. Food and Drug Administration. Few complications have been reported regarding the liquid adhesive entering the wound. The following report involves a patient who developed intestinal occlusion secondary to octylcyanoacrylate used for skin closure in laparoscopic surgery.

Comparative Dynamics of Retrograde Actin Flow and Focal Adhesions: Formation of Nascent Adhesions Triggers Transition from Fast to Slow Flow

PubMed Central

Alexandrova, Antonina Y.; Arnold, Katya; Schaub, Sébastien; Vasiliev, Jury M.; Meister, Jean-Jacques; Bershadsky, Alexander D.; Verkhovsky, Alexander B.

2008-01-01

Dynamic actin network at the leading edge of the cell is linked to the extracellular matrix through focal adhesions (FAs), and at the same time it undergoes retrograde flow with different dynamics in two distinct zones: the lamellipodium (peripheral zone of fast flow), and the lamellum (zone of slow flow located between the lamellipodium and the cell body). Cell migration involves expansion of both the lamellipodium and the lamellum, as well as formation of new FAs, but it is largely unknown how the position of the boundary between the two flow zones is defined, and how FAs and actin flow mutually influence each other. We investigated dynamic relationship between focal adhesions and the boundary between the two flow zones in spreading cells. Nascent FAs first appeared in the lamellipodium. Within seconds after the formation of new FAs, the rate of actin flow decreased locally, and the lamellipodium/lamellum boundary advanced towards the new FAs. Blocking fast actin flow with cytochalasin D resulted in rapid dissolution of nascent FAs. In the absence of FAs (spreading on poly-L-lysine-coated surfaces) retrograde flow was uniform and the velocity transition was not observed. We conclude that formation of FAs depends on actin dynamics, and in its turn, affects the dynamics of actin flow by triggering transition from fast to slow flow. Extension of the cell edge thus proceeds through a cycle of lamellipodium protrusion, formation of new FAs, advance of the lamellum, and protrusion of the lamellipodium from the new base. PMID:18800171

Evaluation of the effects of fulvestrant and micronized progesterone on the post-operative adhesion formation and ovarian reserve in rat model with immunohistochemical and biochemical analysis.

PubMed

Oner, Gokalp; Ulug, Pasa; Demirci, Elif; Kumtepe, Yakup; Gündogdu, Cemal

2015-01-01

To evaluate the effects of fulvestrant and micronized progesterone on post-operative adhesion formation and ovarian reserve in a rat uterine horn adhesion. In this prospective randomized controlled trial, 32 female Wistar albino rats were randomly divided into four groups including control group (Group 1), the control adhesion group (Group 2), 1 mg/kg daily intramuscular fulvestrant received group (Group 3) and 1 mg/kg daily oral micronized progesterone received group (Group 4). The extent and severity of adhesions were scored and samples were taken from adhesion areas to investigate the grades of adhesions according to the immunohistochemical scoring system. Ovarian reserves were measured with anti-Müllerian hormone (AMH) and histological ovarian follicles count. The extent, severity and total adhesion scores were reduced in all treatment groups compared to control adhesion group (Group 2). Similarly, immunohistochemical adhesion scores were lower in the treatment groups. AMH and follicle count were significantly found lower in adhesion groups compared with control group. However, treatment groups were found to have higher ovarian reserve compared to control adhesion group (Group 2). Fulvestrant and micronized progesterone were found to reduce post-operative adhesion formations and have decreased detrimental effects of adhesion formation on ovarian reserve.

Clinico-hysteroscopic analysis of severe intrauterine adhesions among Nigerian infertile women.

PubMed

Ugboaja, Joseph Odirichukwu; Oguejiofor, Charlotte Blanche; Igwegbe, Anthony Osita

2017-01-01

Severe intrauterine adhesions are difficult to manage and are associated with poor reproductive outcomes following treatment. The objective was to study the clinical presentation and hysteroscopic findings of severe intrauterine adhesions seen at hysteroscopy in two fertility/gynaecological endoscopy units in Nigeria. A prospective study of 19 out of 76 women managed for intrauterine adhesions in our units. Data were analyzed with STATA software, version 12.0 SE (Stata Corporation, TX, USA). Severe intrauterine adhesion accounted for 19 (25.0%) of 76 cases of intrauterine adhesions managed during the period. This constituted 11.9% of 160 infertile women who had diagnostic hysteroscopies in our units over the study period. The mean duration of symptom was 4.2 years +/-3.2. Amenorrhea in association with infertility (68.4%) was the main presenting complaint. Secondary dysmenorrhea and cyclical abdominal pain were found in 10.8% and 31.6% of the women respectively. The main aetiological events were complicated caesarean section (42.1%) and abdominal myomectomy (26.3%). The adhesions were mainly dense (52.6%) and multiple (94.7%) with complete involvement of the uterine cavity in all the cases. Obliterative lesions were seen in 63.2% of the women. The main clinical presentation of severe IUA was amenorrhea and infertility while the major risk factors were complicated caesarean section and myomectomy. The adhesions were mainly multiple, dense, obliterative and complete.

Spatiotemporal distribution of different extracellular polymeric substances and filamentation mediate Xylella fastidiosa adhesion and biofilm formation.

PubMed

Janissen, Richard; Murillo, Duber M; Niza, Barbara; Sahoo, Prasana K; Nobrega, Marcelo M; Cesar, Carlos L; Temperini, Marcia L A; Carvalho, Hernandes F; de Souza, Alessandra A; Cotta, Monica A

2015-04-20

Microorganism pathogenicity strongly relies on the generation of multicellular assemblies, called biofilms. Understanding their organization can unveil vulnerabilities leading to potential treatments; spatially and temporally-resolved comprehensive experimental characterization can provide new details of biofilm formation, and possibly new targets for disease control. Here, biofilm formation of economically important phytopathogen Xylella fastidiosa was analyzed at single-cell resolution using nanometer-resolution spectro-microscopy techniques, addressing the role of different types of extracellular polymeric substances (EPS) at each stage of the entire bacterial life cycle. Single cell adhesion is caused by unspecific electrostatic interactions through proteins at the cell polar region, where EPS accumulation is required for more firmly-attached, irreversibly adhered cells. Subsequently, bacteria form clusters, which are embedded in secreted loosely-bound EPS, and bridged by up to ten-fold elongated cells that form the biofilm framework. During biofilm maturation, soluble EPS forms a filamentous matrix that facilitates cell adhesion and provides mechanical support, while the biofilm keeps anchored by few cells. This floating architecture maximizes nutrient distribution while allowing detachment upon larger shear stresses; it thus complies with biological requirements of the bacteria life cycle. Using new approaches, our findings provide insights regarding different aspects of the adhesion process of X. fastidiosa and biofilm formation.

Spatiotemporal distribution of different extracellular polymeric substances and filamentation mediate Xylella fastidiosa adhesion and biofilm formation

PubMed Central

Janissen, Richard; Murillo, Duber M.; Niza, Barbara; Sahoo, Prasana K.; Nobrega, Marcelo M.; Cesar, Carlos L.; Temperini, Marcia L. A.; Carvalho, Hernandes F.; de Souza, Alessandra A.; Cotta, Monica A.

2015-01-01

Microorganism pathogenicity strongly relies on the generation of multicellular assemblies, called biofilms. Understanding their organization can unveil vulnerabilities leading to potential treatments; spatially and temporally-resolved comprehensive experimental characterization can provide new details of biofilm formation, and possibly new targets for disease control. Here, biofilm formation of economically important phytopathogen Xylella fastidiosa was analyzed at single-cell resolution using nanometer-resolution spectro-microscopy techniques, addressing the role of different types of extracellular polymeric substances (EPS) at each stage of the entire bacterial life cycle. Single cell adhesion is caused by unspecific electrostatic interactions through proteins at the cell polar region, where EPS accumulation is required for more firmly-attached, irreversibly adhered cells. Subsequently, bacteria form clusters, which are embedded in secreted loosely-bound EPS, and bridged by up to ten-fold elongated cells that form the biofilm framework. During biofilm maturation, soluble EPS forms a filamentous matrix that facilitates cell adhesion and provides mechanical support, while the biofilm keeps anchored by few cells. This floating architecture maximizes nutrient distribution while allowing detachment upon larger shear stresses; it thus complies with biological requirements of the bacteria life cycle. Using new approaches, our findings provide insights regarding different aspects of the adhesion process of X. fastidiosa and biofilm formation. PMID:25891045

[Influence of slime production and adhesion of Candida sp. on biofilm formation].

PubMed

Ciok-Pater, Emilia; Smolak, Przemysław; Wróblewska, Joanna; Gospodarek, Eugenia

2011-01-01

The increase of fungal infections in recent years is connected with the progress in medicine. The vast usage of biomaterials is an inseparable element of contemporary medicine but it also leads to development of infections. Yeast-like fungi Candida albicans are still the main pathogen of candidiasis. The ability to slime production and adhesion to polystyrene of Candida sp. on different surfaces can cause to form biofilm on surfaces of biomaterials used in production of catheters, drains and prosthesis. The aim of the study was to evaluate the influence of slime production and adhesion to polystyrene, of Candida sp. on biofilm formation on different biomaterials. 50 strains of Candida sp. were examined. They isolated from ill to Clinics of Anesthesiology and Intensive Therapy University Hospital No 1 of dr. A. Jurasza in Bydgoszcz. The ability to slime production was evaluated by Christensen method in modification Davenport and Branchini methods. The adhesion to polystyrene was evaluated by Richards et el method. The ability to produce biofilm biomaterials by the studied fungi was measured after 72 hours of incubation at 37 degrees C on different biomaterials. Yeast-like fungi Candida sp. fabricating slime and adhesion forming frequently biofilm on surface researched of biomaterials. Influence of chosen biological specificity ascertain on the ability to produce biofilm on surfaces of siliconized latex and polyvinylchloride.

Closure of abdominal wounds by adhesive strips: a clinical trial.

PubMed Central

Webster, D J; Davis, P W

1975-01-01

In a randomized trial of wound closure in 512 abdominal wounds, wounds were closed with either reinforced Steristrip skin closures or interrupted silk sutures. Comparisons were made of wound pain and discomfort, wound infection, discharge, redness, width, and skin reaction. The causes of peeling of the tapes were assessed. The results showed that tapes were significantly more comfortable and that patients preferred them to sutures (P less than 0.01), but wide scars occurred more often. There was no difference in rates of wound infection and no case of allergy to the tapes was seen. Closure of abdominal wounds by these tapes is a satisfactory procedure that could be used more extensively. PMID:1100188

A critical role of platelet adhesion in the initiation of atherosclerotic lesion formation.

PubMed

Massberg, Steffen; Brand, Korbinian; Grüner, Sabine; Page, Sharon; Müller, Elke; Müller, Iris; Bergmeier, Wolfgang; Richter, Thomas; Lorenz, Michael; Konrad, Ildiko; Nieswandt, Bernhard; Gawaz, Meinrad

2002-10-07

The contribution of platelets to the process of atherosclerosis remains unclear. Here, we show in vivo that platelets adhere to the vascular endothelium of the carotid artery in ApoE(-)(/)(-) mice before the development of manifest atherosclerotic lesions. Platelet-endothelial cell interaction involved both platelet glycoprotein (GP)Ibalpha and GPIIb-IIIa. Platelet adhesion to the endothelium coincides with inflammatory gene expression and preceded atherosclerotic plaque invasion by leukocytes. Prolonged blockade of platelet adhesion in ApoE(-)(/)(-) mice profoundly reduced leukocyte accumulation in the arterial intima and attenuated atherosclerotic lesion formation in the carotid artery bifurcation, the aortic sinus, and the coronary arteries. These findings establish the platelet as a major player in initiation of the atherogenetic process.

Culture Supernatants of Lactobacillus gasseri and L. crispatus Inhibit Candida albicans Biofilm Formation and Adhesion to HeLa Cells.

PubMed

Matsuda, Yuko; Cho, Otomi; Sugita, Takashi; Ogishima, Daiki; Takeda, Satoru

2018-03-30

Vulvovaginal candidiasis (VVC) is a common superficial infection of the vaginal mucous membranes caused by the fungus Candida albicans. The aim of this study was to assess the mechanisms underlying the inhibitory effects of the culture supernatants of Lactobacillus gasseri and L. crispatus, the predominant microbiota in Asian healthy women, on C. albicans biofilm formation. The inhibition of C. albicans adhesion to HeLa cells by Lactobacillus culture supernatant was also investigated. Candida albicans biofilm was formed on polystyrene flat-bottomed 96-well plates, and the inhibitory effects on the initial colonization and maturation phases were determined using the XTT reduction assay. The expression levels of biofilm formation-associated genes (HWP1, ECE1, ALS3, BCR1, EFG1, TEC1, and CPH1) were determined by reverse transcription quantitative polymerase chain reaction. The inhibition of C. albicans adhesion to HeLa cells by Lactobacillus culture supernatant was evaluated by enumerating viable C. albicans cells. The culture supernatants of both Lactobacillus species inhibited the initial colonization and maturation of C. albicans biofilm. The expression levels of all biofilm formation-related genes were downregulated in the presence of Lactobacillus culture supernatant. The culture supernatant also inhibited C. albicans adhesion to HeLa cells. The culture supernatants of L. gasseri and L. crispatus inhibited C. albicans biofilm formation by downregulating biofilm formation-related genes and C. albicans adhesion to HeLa cells. These findings support the notion that Lactobacillus metabolites may be useful alternatives to antifungal drugs for the management of VVC.

Adhesion enhancement of biomimetic dry adhesives by nanoparticle in situ synthesis

NASA Astrophysics Data System (ADS)

Díaz Téllez, J. P.; Harirchian-Saei, S.; Li, Y.; Menon, C.

2013-10-01

A novel method to increase the adhesion strength of a gecko-inspired dry adhesive is presented. Gold nanoparticles are synthesized on the tips of the microfibrils of a polymeric dry adhesive to increase its Hamaker constant. Formation of the gold nanoparticles is qualitatively studied through a colour change in the originally transparent substance and quantitatively analysed using ultraviolet-visible spectrophotometry. A pull-off force test is employed to quantify the adhesion enhancement. Specifically, adhesion forces of samples with and without embedded gold nanoparticles are measured and compared. The experimental results indicate that an adhesion improvement of 135% can be achieved.

An integrated fluid-chemical model toward modeling the formation of intra-luminal thrombus in abdominal aortic aneurysms.

PubMed

Biasetti, Jacopo; Spazzini, Pier Giorgio; Swedenborg, Jesper; Gasser, T Christian

2012-01-01

Abdominal Aortic Aneurysms (AAAs) are frequently characterized by the presence of an Intra-Luminal Thrombus (ILT) known to influence their evolution biochemically and biomechanically. The ILT progression mechanism is still unclear and little is known regarding the impact of the chemical species transported by blood flow on this mechanism. Chemical agonists and antagonists of platelets activation, aggregation, and adhesion and the proteins involved in the coagulation cascade (CC) may play an important role in ILT development. Starting from this assumption, the evolution of chemical species involved in the CC, their relation to coherent vortical structures (VSs) and their possible effect on ILT evolution have been studied. To this end a fluid-chemical model that simulates the CC through a series of convection-diffusion-reaction (CDR) equations has been developed. The model involves plasma-phase and surface-bound enzymes and zymogens, and includes both plasma-phase and membrane-phase reactions. Blood is modeled as a non-Newtonian incompressible fluid. VSs convect thrombin in the domain and lead to the high concentration observed in the distal portion of the AAA. This finding is in line with the clinical observations showing that the thickest ILT is usually seen in the distal AAA region. The proposed model, due to its ability to couple the fluid and chemical domains, provides an integrated mechanochemical picture that potentially could help unveil mechanisms of ILT formation and development.

Teneurin-4 promotes cellular protrusion formation and neurite outgrowth through focal adhesion kinase signaling

PubMed Central

Suzuki, Nobuharu; Numakawa, Tadahiro; Chou, Joshua; de Vega, Susana; Mizuniwa, Chihiro; Sekimoto, Kaori; Adachi, Naoki; Kunugi, Hiroshi; Arikawa-Hirasawa, Eri; Yamada, Yoshihiko; Akazawa, Chihiro

2014-01-01

Teneurin-4 (Ten-4), a transmembrane protein, is highly expressed in the central nervous system; however, its cellular and molecular function in neuronal differentiation remains unknown. In this study, we aimed to elucidate the function of Ten-4 in neurite outgrowth. Ten-4 expression was induced during neurite outgrowth of the neuroblastoma cell line Neuro-2a. Ten-4 protein was localized at the neurite growth cones. Knockdown of Ten-4 expression in Neuro-2a cells decreased the formation of the filopodia-like protrusions and the length of individual neurites. Conversely, overexpression of Ten-4 promoted filopodia-like protrusion formation. In addition, knockdown and overexpression of Ten-4 reduced and elevated the activation of focal adhesion kinase (FAK) and Rho-family small GTPases, Cdc42 and Rac1, key molecules for the membranous protrusion formation downstream of FAK, respectively. Inhibition of the activation of FAK and neural Wiskott-Aldrich syndrome protein (N-WASP), which is a downstream regulator of FAK and Cdc42, blocked protrusion formation by Ten-4 overexpression. Further, Ten-4 colocalized with phosphorylated FAK in the filopodia-like protrusion regions. Together, our findings show that Ten-4 is a novel positive regulator of cellular protrusion formation and neurite outgrowth through the FAK signaling pathway.—Suzuki, N., Numakawa, T., Chou, J., de Vega, S., Mizuniwa, C., Sekimoto, K., Adachi, N., Kunugi, H., Arikawa-Hirasawa, E., Yamada, Y., Akazawa, C. Teneurin-4 promotes cellular protrusion formation and neurite outgrowth through focal adhesion kinase signaling. PMID:24344332

Thermography Examination of Abdominal Area Skin Temperatures in Individuals With and Without Focal-Onset Epilepsy.

PubMed

King, Hollis H; Cayce, Charles Thomas; Herrin, Jeph

Early osteopathic theory and practice, and the work of the medical intuitive Edgar Cayce suggested that the abdominal areas of individuals with epilepsy would manifest "cold spots." The etiology for this phenomenon was thought to be abdominal adhesions caused by inflammation and viscero-somatic reflexes caused by adhesions or injury to visceral or musculoskeletal system structures. Indeed, until that advent of electroencephalography in the 1930s, medical practice regarding epilepsy focused on abdominal neural and visceral structures. Following two hypotheses were formulated to evaluate any abdominal temperature phenomena: (1) an abdominal quadrant division analysis would find one or more quadrants "colder" in the focal-onset epilepsy group (ICD9-CM 345.4 and 345.5) compared to controls. (2) Total abdominal areas of individuals with focal-onset epilepsy wound be colder than a control group. Overall, 50 patients with the diagnosis of focal-onset epilepsy were recruited from the office of the Epilepsy Foundation of Florida and 50 control subjects with no history of epilepsy were recruited through advertising to the public. Under controlled room conditions all subjects had infrared thermographic images made and recorded by Med-Hot Model MH-731 FLIR equipment. There were no significant demographic difference between experimental patients and control subjects, though the control group tended to be younger and more often male; however, these were controlled for in all analyses. In the quadrant analysis, there were significant differences in that more epileptic patients had colder left upper abdominal quadrant temperatures than the control group (66.8% versus 44.9%; P = .030). In the total abdominal analysis, however, there were no significant differences. The results support the hypothesis that individuals with focal-onset epilepsy have colder abdominal areas. If substantiated in further research, present study results will require further examination of the mechanisms of

Efficacy and safety of the C-Qur™ Film Adhesion Barrier for the prevention of surgical adhesions (CLIPEUS Trial): study protocol for a randomized controlled trial.

PubMed

Stommel, Martijn W J; Strik, Chema; ten Broek, Richard P G; van Goor, Harry

2014-09-26

Adhesions develop in over 90% of patients after intra-abdominal surgery. Adhesion barriers are rarely used despite the high morbidity caused by intra-abdominal adhesions. Only one of the currently available adhesion barriers has demonstrated consistent evidence for reducing adhesions in visceral surgery. This agent has limitations through poor handling characteristics because it is sticky on both sides. C-Qur™ Film is a novel thin film adhesion barrier and it is sticky on only one side, resulting in better handling characteristics. The objective of this study is to assess efficacy and safety of C-Qur™ Film to decrease the incidence of adhesions after colorectal surgery. This is a prospective, investigator initiated, randomized, double-blinded, multicenter trial. Eligible patients undergoing colorectal resection requiring temporary loop ileostomy or loop/split colostomy by laparotomy or hand assisted laparoscopy will be included in the trial. Before closure, patients are randomized 1:1 to either the treatment arm (C-Qur™ Film) or control arm (no adhesion barrier). Patients will return 8 to 16 weeks post-colorectal resection for take down of their ostomy. During ostomy takedown, adhesions will be evaluated for incidence, extent, and severity. The primary outcome evaluation will be assessment of adhesions to the incision site. It is hypothesized that the use of C-Qur™ Film underneath the primary incision reduces the incidence of adhesion at the incision by 30%. To demonstrate 30% reduction in the incidence of adhesions, a sample size of 84 patients (32 + 10 per group (25% drop out)) is required (two-sided test, α = 0.05, 80% power). Results of this study add to the evidence on the use of anti-adhesive barriers in open and laparoscopic 'hand-assisted' colorectal surgery. We chose incidence of adhesions to the incision site as primary outcome measure since clinical outcomes such as small bowel obstruction, secondary infertility and adhesiolysis related

A Critical Role of Platelet Adhesion in the Initiation of Atherosclerotic Lesion Formation

PubMed Central

Massberg, Steffen; Brand, Korbinian; Grüner, Sabine; Page, Sharon; Müller, Elke; Müller, Iris; Bergmeier, Wolfgang; Richter, Thomas; Lorenz, Michael; Konrad, Ildiko; Nieswandt, Bernhard; Gawaz, Meinrad

2002-01-01

The contribution of platelets to the process of atherosclerosis remains unclear. Here, we show in vivo that platelets adhere to the vascular endothelium of the carotid artery in ApoE − / − mice before the development of manifest atherosclerotic lesions. Platelet–endothelial cell interaction involved both platelet glycoprotein (GP)Ibα and GPIIb-IIIa. Platelet adhesion to the endothelium coincides with inflammatory gene expression and preceded atherosclerotic plaque invasion by leukocytes. Prolonged blockade of platelet adhesion in ApoE − / − mice profoundly reduced leukocyte accumulation in the arterial intima and attenuated atherosclerotic lesion formation in the carotid artery bifurcation, the aortic sinus, and the coronary arteries. These findings establish the platelet as a major player in initiation of the atherogenetic process. PMID:12370251

PM2.5 promotes abdominal aortic aneurysm formation in angiotensin Ⅱ-infused apoe-/- mice.

PubMed

Jun, Xie; Jin, Geng; Fu, Chen; Jinxuan, Zhao; Xuelin, Li; Jiaxin, Hu; Shuaihua, Qiao; Anqi, Shan; Jianzhou, Chen; Lian, Zhou; Xiwen, Zhang; Baoli, Zhu; Biao, Xu

2018-08-01

Particulate matter 2.5 (PM2.5) has proven to be associated with morbidity and mortality from cardiovascular diseases. However, whether PM2.5 could promote the formation of abdominal aortic aneurysm (AAA) is unclear. Present study aimed to explore the relationship between PM2.5 exposure and AAA development. Ang Ⅱ-infused apoe -/- mice were treated with PM2.5 or saline by intranasal instillation. Four weeks later, histological and immunohistological analyses were used to evaluate the effect of PM2.5 on AAA formation. Human aortic smooth muscle cells (HASMCs) were also employed to further analyze the adverse effect of PM2.5 in vitro. We found that PM2.5 could significantly increase the AAA incidence, the maximal abdominal aortic diameter and could promote the degradation of elastin. Additionally, the expression of senescence markers, P21 and P16 were also enhanced after PM2.5 exposure. We also found that PM2.5 significantly increased the AAA related pathological changes, MMP2 and MCP-1 expression in HASMCs. Meanwhile, PM2.5 could increase the expression of senescence markers P21, P16 and SA-β-gal activity, also the reactive oxygen species levels in vitro. PM2.5 promoted the formation of AAA in an Ang Ⅱ-induced AAA model. The underlying mechanism might be cellular senescence after PM2.5 exposure. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Rabbit Achilles tendon full transection model – wound healing, adhesion formation and biomechanics at 3, 6 and 12 weeks post-surgery

PubMed Central

Meier Bürgisser, Gabriella; Calcagni, Maurizio; Bachmann, Elias; Fessel, Gion; Snedeker, Jess G.; Giovanoli, Pietro

2016-01-01

ABSTRACT After tendon rupture repair, two main problems may occur: re-rupture and adhesion formation. Suitable non-murine animal models are needed to study the healing tendon in terms of biomechanical properties and extent of adhesion formation. In this study 24 New Zealand White rabbits received a full transection of the Achilles tendon 2 cm above the calcaneus, sutured with a 4-strand Becker suture. Post-surgical analysis was performed at 3, 6 and 12 weeks. In the 6-week group, animals received a cast either in a 180 deg stretched position during 6 weeks (adhesion provoking immobilization), or were re-casted with a 150 deg position after 3 weeks (adhesion inhibiting immobilization), while in the other groups (3 and 12 weeks) a 180 deg position cast was applied for 3 weeks. Adhesion extent was analyzed by histology and ultrasound. Histopathological scoring was performed according to a method by Stoll et al. (2011), and the main biomechanical properties were assessed. Histopathological scores increased as a function of time, but did not reach values of healthy tendons after 12 weeks (only around 15 out of 20 points). Adhesion provoking immobilization led to an adhesion extent of 82.7±9.7%, while adhesion inhibiting immobilization led to 31.9±9.8% after 6 weeks. Biomechanical properties increased over time, however, they did not reach full strength nor elastic modulus at 12 weeks post-operation. Furthermore, the rabbit Achilles tendon model can be modulated in terms of adhesion formation to the surrounding tissue. It clearly shows the different healing stages in terms of histopathology and offers a suitable model regarding biomechanics because it exhibits similar biomechanics as the human flexor tendons of the hand. PMID:27635037

Capric Acid Secreted by S. boulardii Inhibits C. albicans Filamentous Growth, Adhesion and Biofilm Formation

PubMed Central

Murzyn, Anna; Krasowska, Anna; Stefanowicz, Piotr; Dziadkowiec, Dorota; Łukaszewicz, Marcin

2010-01-01

Candidiasis are life-threatening systemic fungal diseases, especially of gastro intestinal track, skin and mucous membranes lining various body cavities like the nostrils, the mouth, the lips, the eyelids, the ears or the genital area. Due to increasing resistance of candidiasis to existing drugs, it is very important to look for new strategies helping the treatment of such fungal diseases. One promising strategy is the use of the probiotic microorganisms, which when administered in adequate amounts confer a health benefit. Such a probiotic microorganism is yeast Saccharomyces boulardii, a close relative of baker yeast. Saccharomyces boulardii cells and their extract affect the virulence factors of the important human fungal pathogen C. albicans, its hyphae formation, adhesion and biofilm development. Extract prepared from S. boulardii culture filtrate was fractionated and GC-MS analysis showed that the active fraction contained, apart from 2-phenylethanol, caproic, caprylic and capric acid whose presence was confirmed by ESI-MS analysis. Biological activity was tested on C. albicans using extract and pure identified compounds. Our study demonstrated that this probiotic yeast secretes into the medium active compounds reducing candidal virulence factors. The chief compound inhibiting filamentous C. albicans growth comparably to S. boulardii extract was capric acid, which is thus responsible for inhibition of hyphae formation. It also reduced candidal adhesion and biofilm formation, though three times less than the extract, which thus contains other factors suppressing C. albicans adherence. The expression profile of selected genes associated with C. albicans virulence by real-time PCR showed a reduced expression of HWP1, INO1 and CSH1 genes in C. albicans cells treated with capric acid and S. boulardii extract. Hence capric acid secreted by S. boulardii is responsible for inhibition of C. albicans filamentation and partially also adhesion and biofilm formation. PMID

Non-cross-linked porcine acellular dermal matrices for abdominal wall reconstruction.

PubMed

Burns, Nadja K; Jaffari, Mona V; Rios, Carmen N; Mathur, Anshu B; Butler, Charles E

2010-01-01

Non-cross-linked porcine acellular dermal matrices have been used clinically for abdominal wall repair; however, their biologic and mechanical properties and propensity to form visceral adhesions have not been studied. The authors hypothesized that their use would result in fewer, weaker visceral adhesions than polypropylene mesh when used to repair ventral hernias and form a strong interface with the surrounding musculofascia. Thirty-four guinea pigs underwent inlay repair of surgically created ventral hernias using polypropylene mesh, porcine acellular dermal matrix, or a composite of the two. The animals were killed at 4 weeks, and the adhesion tenacity grade and surface area of the repair site involved by adhesions were measured. Sections of the repair sites, including the implant-musculofascia interface, underwent histologic analysis and uniaxial mechanical testing. The incidence of bowel adhesions to the repair site was significantly lower with the dermal matrix (8 percent, p < 0.01) and the matrix/mesh combination (0 percent, p < 0.001) than with polypropylene mesh alone (70 percent). The repairs made with the matrix or the matrix/mesh combination, compared with the polypropylene mesh repairs, had significantly lower mean adhesion surface areas [12.8 percent (p < 0.001), 9.2 percent (p < 0.001), and 79.9 percent] and grades [0.6 (p < 0.001), 0.6 (p < 0.001), and 2.9]. The dermal matrix underwent robust cellular and vascular infiltration. The ultimate tensile strength at the implant-musculofascia interface was similar in all groups. Porcine acellular dermal matrix becomes incorporated into the host tissue and causes fewer adhesions to repair sites than does polypropylene mesh, with similar implant-musculofascia interface strength. It also inhibits adhesions to adjacent dermal matrix in the combination repairs. It has distinct advantages over polypropylene mesh for complex abdominal wall repairs, particularly when material placement directly over bowel is

Reversible Thermoset Adhesives

NASA Technical Reports Server (NTRS)

Mac Murray, Benjamin C. (Inventor); Tong, Tat H. (Inventor); Hreha, Richard D. (Inventor)

2016-01-01

Embodiments of a reversible thermoset adhesive formed by incorporating thermally-reversible cross-linking units and a method for making the reversible thermoset adhesive are provided. One approach to formulating reversible thermoset adhesives includes incorporating dienes, such as furans, and dienophiles, such as maleimides, into a polymer network as reversible covalent cross-links using Diels Alder cross-link formation between the diene and dienophile. The chemical components may be selected based on their compatibility with adhesive chemistry as well as their ability to undergo controlled, reversible cross-linking chemistry.

The cell adhesion molecule nectin-1 is critical for normal enamel formation in mice

PubMed Central

Barron, Martin J.; Brookes, Steven J.; Draper, Clare E.; Garrod, David; Kirkham, Jennifer; Shore, Roger C.; Dixon, Michael J.

2008-01-01

Nectin-1 is a member of a sub-family of immunoglobulin-like adhesion molecules and a component of adherens junctions. In the current study, we have shown that mice lacking nectin-1 exhibit defective enamel formation in their incisor teeth. Although the incisors of nectin-1-null mice were hypomineralized, the protein composition of the enamel matrix was unaltered. While strong immunostaining for nectin-1 was observed at the interface between the maturation-stage ameloblasts and the underlying cells of the stratum intermedium (SI), its absence in nectin-1-null mice correlated with separation of the cell layers at this interface. Numerous, large desmosomes were present at this interface in wild-type mice; however, where adhesion persisted in the mutant mice, the desmosomes were smaller and less numerous. Nectins have been shown to regulate tight junction formation; however, this is the first report showing that they may also participate in the regulation of desmosome assembly. Importantly, our results show that integrity of the SI–ameloblast interface is essential for normal enamel mineralization. PMID:18703497

Lateral assembly of the immunoglobulin protein SynCAM 1 controls its adhesive function and instructs synapse formation.

PubMed

Fogel, Adam I; Stagi, Massimiliano; Perez de Arce, Karen; Biederer, Thomas

2011-09-16

Synapses are specialized adhesion sites between neurons that are connected by protein complexes spanning the synaptic cleft. These trans-synaptic interactions can organize synapse formation, but their macromolecular properties and effects on synaptic morphology remain incompletely understood. Here, we demonstrate that the synaptic cell adhesion molecule SynCAM 1 self-assembles laterally via its extracellular, membrane-proximal immunoglobulin (Ig) domains 2 and 3. This cis oligomerization generates SynCAM oligomers with increased adhesive capacity and instructs the interactions of this molecule across the nascent and mature synaptic cleft. In immature neurons, cis assembly promotes the adhesive clustering of SynCAM 1 at new axo-dendritic contacts. Interfering with the lateral self-assembly of SynCAM 1 in differentiating neurons strongly impairs its synaptogenic activity. At later stages, the lateral oligomerization of SynCAM 1 restricts synaptic size, indicating that this adhesion molecule contributes to the structural organization of synapses. These results support that lateral interactions assemble SynCAM complexes within the synaptic cleft to promote synapse induction and modulate their structure. These findings provide novel insights into synapse development and the adhesive mechanisms of Ig superfamily members.

Role of the medial medullary reticular formation in relaying vestibular signals to the diaphragm and abdominal muscles

NASA Technical Reports Server (NTRS)

Mori, R. L.; Bergsman, A. E.; Holmes, M. J.; Yates, B. J.

2001-01-01

Changes in posture can affect the resting length of respiratory muscles, requiring alterations in the activity of these muscles if ventilation is to be unaffected. Recent studies have shown that the vestibular system contributes to altering respiratory muscle activity during movement and changes in posture. Furthermore, anatomical studies have demonstrated that many bulbospinal neurons in the medial medullary reticular formation (MRF) provide inputs to phrenic and abdominal motoneurons; because this region of the reticular formation receives substantial vestibular and other movement-related input, it seems likely that medial medullary reticulospinal neurons could adjust the activity of respiratory motoneurons during postural alterations. The objective of the present study was to determine whether functional lesions of the MRF affect inspiratory and expiratory muscle responses to activation of the vestibular system. Lidocaine or muscimol injections into the MRF produced a large increase in diaphragm and abdominal muscle responses to vestibular stimulation. These vestibulo-respiratory responses were eliminated following subsequent chemical blockade of descending pathways in the lateral medulla. However, inactivation of pathways coursing through the lateral medulla eliminated excitatory, but not inhibitory, components of vestibulo-respiratory responses. The simplest explanation for these data is that MRF neurons that receive input from the vestibular nuclei make inhibitory connections with diaphragm and abdominal motoneurons, whereas a pathway that courses laterally in the caudal medulla provides excitatory vestibular inputs to these motoneurons.

Chance of adhesion formation after laparoscopic salpingo-ovariolysis: is there a place for second-look laparoscopy?

PubMed

Alborzi, Saeed; Motazedian, Shahdokht; Parsanezhad, Mohammad E

2003-05-01

To evaluate the chance of adhesion formation after laparoscopic salpingo-ovariolysis and determine the efficacy of early second-look laparoscopy (SLL). Prospective, randomized study (Canadian Task Force classification I). Shiraz University hospitals. Ninety women with mean duration of infertility of 7.2 years. Operative laparoscopy, with early SLL with adhesiolysis in 46 (group 1) and no SLL in 44 women (group 2). Adnexal adhesions were evaluated according to American Society for Reproductive Medicine adhesion classification. Separation of newly reformed adhesions was performed at the time of SLL. Patients were followed for a year after operation without other infertility treatment. At the time of operation in group 1, adnexal adhesions were graded as severe (class D) in 19 women, moderate (class C) in 31, mild (class B) in 28, and minimal (class A) in 14. Respective figures in group 2 were 10, 30, 34, and 14. After salpingo-ovariolysis these figures were 12, 10, 20, and 50 in group 1 and 6, 14, 17, and 51 in group 2. In group 1 in whom early second-look laparoscopy was performed, at the start of the operation these figures were 17, 20, 21, and 34, and after operation 12, 8, 20, and 52, respectively. There were 11 term pregnancies in group 1 and 15 in group 2. No women with severe adhesions in either group conceived. In group 1, chances of term pregnancy were 18.75% for those with moderate adhesions, 35.71% for women with mild adhesions, and 42.86% in patients with minimal adhesions. Respective figures in group 2 were 26.67%, 41.18%, and 57.14%. The chance of moderate and severe adhesion reformation after laparoscopic salpingo-ovariolysis was 40.2%. Although separation of these adhesions could be performed more easily at the time of early SLL, the chance of pregnancy did not increase compared with that in patients who did not undergo SLL.

The Role of Cell-Cell Adhesion in the Formation of Multicellular Sprouts

PubMed Central

Szabó, A.; Czirók, A.

2010-01-01

Collective cell motility and its guidance via cell-cell contacts is instrumental in several morphogenetic and pathological processes such as vasculogenesis or tumor growth. Multicellular sprout elongation, one of the simplest cases of collective motility, depends on a continuous supply of cells streaming along the sprout towards its tip. The phenomenon is often explained as leader cells pulling the rest of the sprout forward via cell-cell adhesion. Building on an empirically demonstrated analogy between surface tension and cell-cell adhesion, we demonstrate that such a mechanism is unable to recruit cells to the sprout. Moreover, the expansion of such hypothetical sprouts is limited by a form of the Plateau-Taylor instability. In contrast, actively moving cells – guided by cell-cell contacts – can readily populate and expand linear sprouts. We argue that preferential attraction to the surfaces of elongated cells can provide a generic mechanism, shared by several cell types, for multicellular sprout formation. PMID:20165554

The effect of a collagen-elastin matrix on adhesion formation after flexor tendon repair in a rabbit model.

PubMed

Wichelhaus, Dagmar Alice; Beyersdoerfer, Sascha Tobias; Gierer, Philip; Vollmar, Brigitte; Mittlmeier, Th

2016-07-01

The outcome of flexor tendon surgery is negatively affected by the formation of adhesions which can occur during the healing of the tendon repair. In this experimental study, we sought to prevent adhesion formation by wrapping a collagen-elastin scaffold around the repaired tendon segment. In 28 rabbit hind legs, the flexor tendons of the third and fourth digits were cut and then repaired using a two-strand suture technique on the fourth digit and a four-strand technique on the third digit. Rabbits were randomly assigned to study and control groups. In the control group, the operation ended by closing the tendon sheath and the skin. In the study group, a collagen-elastin scaffold was wrapped around the repaired tendon segment in both digits. After 3 and 8 weeks, the tendons were harvested and processed histologically. The range of motion of the digits and the gap formation between the repaired tendon ends were measured. The formation of adhesions, infiltration of leucocytes and extracellular inflammatory response were quantified. At the time of tendon harvesting, all joints of the operated toes showed free range of motion. Four-strand core sutures lead to significantly less diastasis between the repaired tendon ends than two-strand core suture repairs. The collagen-elastin scaffold leads to greater gapping after 3 weeks compared to the controls treated without the matrix. Within the tendons treated with the collagen-elastin matrix, a significant boost of cellular and extracellular inflammation could be stated after 3 weeks which was reflected by a higher level of CAE positive cells and more formation of myofibroblasts in the αSMA stain in the study group. The inflammatory response subsided gradually and significantly until the late stage of the study. Both the cellular and extracellular inflammatory response was emphasized with the amount of material used for the repair. The use of a collagen-elastin matrix cannot be advised for the prevention of adhesion

Exclusion from spheroid formation identifies loss of essential cell-cell adhesion molecules in colon cancer cells.

PubMed

Stadler, Mira; Scherzer, Martin; Walter, Stefanie; Holzner, Silvio; Pudelko, Karoline; Riedl, Angelika; Unger, Christine; Kramer, Nina; Weil, Beatrix; Neesen, Jürgen; Hengstschläger, Markus; Dolznig, Helmut

2018-01-18

Many cell lines derived from solid cancers can form spheroids, which recapitulate tumor cell clusters and are more representative of the in vivo situation than 2D cultures. During spheroid formation, a small proportion of a variety of different colon cancer cell lines did not integrate into the sphere and lost cell-cell adhesion properties. An enrichment protocol was developed to augment the proportion of these cells to 100% purity. The basis for the separation of spheroids from non-spheroid forming (NSF) cells is simple gravity-sedimentation. This protocol gives rise to sub-populations of colon cancer cells with stable loss of cell-cell adhesion. SW620 cells lacked E-cadherin, DLD-1 cells lost α-catenin and HCT116 cells lacked P-cadherin in the NSF state. Knockdown of these molecules in the corresponding spheroid-forming cells demonstrated that loss of the respective proteins were indeed responsible for the NSF phenotypes. Loss of the spheroid forming phenotype was associated with increased migration and invasion properties in all cell lines tested. Hence, we identified critical molecules involved in spheroid formation in different cancer cell lines. We present here a simple, powerful and broadly applicable method to generate new sublines of tumor cell lines to study loss of cell-cell adhesion in cancer progression.

Adhesives with wood materials : bond formation and performance

Treesearch

Charles R. Frihart; Christopher G. Hunt

2010-01-01

Adhesive bonding of wood plays an increasing role in the forest products industry and is a key factor for efficiently utilizing our timber resource. The main use of adhesives is in the manufacture of building materials, including plywood, oriented strandboard, particleboard, fiberboard, structural composite lumber, doors, windows and frames, and factory-laminated wood...

Use of Polypentapeptides of Elastin to Prevent Postoperative Adhesions: Efficacy in a Contaminated Peritoneal Model

DTIC Science & Technology

1994-02-01

short-gut syndrome, rotomy was conducted to reveal the cranial portion of chronic pain , and female infertility [3, 4]. Many sub- the ileum. The abdominal ...hold the sheets in the proper position. The presence of nal adhesions, chronic abdominal pain , and infertility. Gynecol. suture material acting as a...intra- abdominal landmarks. Opera- of 88 rats were studied with random assignment of ani- tions in this situation are often associated with mals to three

Improving Joint Formation and Tensile Properties of Dissimilar Friction Stir Welding of Aluminum and Magnesium Alloys by Solving the Pin Adhesion Problem

NASA Astrophysics Data System (ADS)

Liu, Zhenlei; Ji, Shude; Meng, Xiangchen

2018-03-01

Friction stir welding (FSW), as a solid-state welding technology invented by TWI in 1991, has potential to join dissimilar Al/Mg alloys. In this study, the pin adhesion phenomenon affecting joint quality during FSW of 6061-T6 aluminum and AZ31B magnesium alloys was investigated. The adhesion phenomenon induced by higher heat input easily transformed the tapered-and-screwed pin into a tapered pin, which greatly reduced the tool's ability to drive the plasticized materials and further deteriorated joint formation. Under the condition without the pin adhesion, the complex intercalated interlayer at the bottom of stir zone was beneficial to mechanical interlocking of Al/Mg alloys, improving tensile properties. However, the formation of intermetallic compounds was still the main reason of the joint fracture, significantly deteriorating tensile properties. Under the welding speed of 60 mm/min without the pin adhesion phenomenon, the maximum tensile strength of 107 MPa and elongation of 1.2% were achieved.

Abdominal Cellulitis following a Laparoscopic Procedure: A Rare and Severe Complication

PubMed Central

Bonnard, Arnaud; Terrasa, Jean Baptiste; Viala, Jerome; Aizenfisz, Sophie; Berrebi, Dominique; Ghoneimi, Alaa El

2014-01-01

Advantages of laparoscopic approach in Hirschsprung disease have been already published decreasing the hospital stay and postoperative adhesions. To our knowledge, we report the first case of postoperative abdominal cellulitis after laparoscopic procedure. A laparoscopic Duhamel pull through was done on a 3-month-old child. Full-thickness biopsy under laparoscopy was performed with intraperitoneal inoculation. Large peritoneal irrigation was used. Abdominal necrotizing cellulitis starting from a port site occurred few days after the procedure requiring repeat surgical excision, broad spectrum antibiotics, and hyperbaric oxygen. PMID:25755975

[Influence of electromagnetic emission at the frequencies of molecular absorption and emission spectra of oxygen and nitrogen oxide on the adhesion and formation of Pseudomonas aeruginosa biofilm].

PubMed

Pronina, E A; Shvidenko, I G; Shub, G M; Shapoval, O G

2011-01-01

Evaluate the influence of electromagnetic emission (EME) at the frequencies of molecular absorption and emission spectra of atmospheric oxygen and nitrogen oxide (MAES 02 and MAES NO respectively) on the adhesion, population progress and biofilm formation of Pseudomonas aeruginosa. Adhesive activity was evaluated by mean adhesion index (MAI) of bacteria on human erythrocytes. Population growth dynamic was assessed by optical density index of broth cultures; biofilm formation--by values of optical density of the cells attached to the surface of polystyrol wells. P.aeruginosa bacteria had high adhesive properties that have increased under the influence of MAES 02 frequency emission and have not changed under the influence of MAES NO frequency. Exposure of bacteria to MAES NO frequency did not influence the population progress; exposure to MAES 02 frequency stimulated the biofilm formation ability of the bacteria, and MAES NO--decreased this ability. EME at MAES NO frequency can be used to suppress bacterial biofilm formation by pseudomonas.

Adhesive F-actin Waves: A Novel Integrin-Mediated Adhesion Complex Coupled to Ventral Actin Polymerization

PubMed Central

Case, Lindsay B.; Waterman, Clare M.

2011-01-01

At the leading lamellipodium of migrating cells, protrusion of an Arp2/3-nucleated actin network is coupled to formation of integrin-based adhesions, suggesting that Arp2/3-mediated actin polymerization and integrin-dependent adhesion may be mechanistically linked. Arp2/3 also mediates actin polymerization in structures distinct from the lamellipodium, in “ventral F-actin waves” that propagate as spots and wavefronts along the ventral plasma membrane. Here we show that integrins engage the extracellular matrix downstream of ventral F-actin waves in several mammalian cell lines as well as in primary mouse embryonic fibroblasts. These “adhesive F-actin waves” require a cycle of integrin engagement and disengagement to the extracellular matrix for their formation and propagation, and exhibit morphometry and a hierarchical assembly and disassembly mechanism distinct from other integrin-containing structures. After Arp2/3-mediated actin polymerization, zyxin and VASP are co-recruited to adhesive F-actin waves, followed by paxillin and vinculin, and finally talin and integrin. Adhesive F-actin waves thus represent a previously uncharacterized integrin-based adhesion complex associated with Arp2/3-mediated actin polymerization. PMID:22069459

Reduction of retrosternal and pericardial adhesions with rapidly resorbable polymer films.

PubMed

Okuyama, N; Wang, C Y; Rose, E A; Rodgers, K E; Pines, E; diZerega, G S; Oz, M C

1999-09-01

The formation of postoperative cardiac adhesions makes a repeat sternotomy time consuming and dangerous. Many attempts have been made to solve this problem by using either drugs to inhibit fibrinolytic activity or different types of pericardial substitutes. The results have not been satisfactory. The efficacy of bioresorbable film prototypes made of polyethylene glycol (EO) and polylactic acid (LA) (EO/LA = 1.5, 2.5, and 3.0) in the prevention of adhesions after cardiac operations in canine models was tested. After desiccation and abrasion of the epicardium, a transparent bioresorbable film was placed over the heart. The pericardium was closed to allow intrapericardial adhesions (n = 32) or left open and attached to the chest wall to induce retrosternal adhesions (n = 17). Postoperative recovery was similar among the groups. Retrosternal and pericardial adhesions were evaluated at necropsy 3 weeks later by assessing area, tenacity, and density of the adhesions. In the control dogs, tenacious, dense adhesions were observed. In contrast, adhesion formation was reduced at all sites covered by the films. The bioresorbable films were efficacious in the reduction of adhesion formation between epicardium and pericardium or between epicardium and sternum after cardiac operation. The EO/LA 1.5 film most effectively prevented the early adhesions. The bioresorbable films (EO/LA = 1.5, 2.5, and 3.0) significantly reduced adhesion formation, with EO/LA = 1.5 (Repel CV) being optimal. As the barrier was rapidly resorbed, the capsule formation induced by permanent barriers was avoided.

Profiling of Candida albicans Gene Expression During Intra-abdominal Candidiasis Identifies Biologic Processes Involved in Pathogenesis

PubMed Central

Cheng, Shaoji; Clancy, Cornelius J.; Xu, Wenjie; Schneider, Frank; Hao, Binghua; Mitchell, Aaron P.; Nguyen, M. Hong

2013-01-01

Background. The pathogenesis of intra-abdominal candidiasis is poorly understood. Methods. Mice were intraperitoneally infected with Candida albicans (1 × 106 colony-forming units) and sterile stool. nanoString assays were used to quantitate messenger RNA for 145 C. albicans genes within the peritoneal cavity at 48 hours. Results. Within 6 hours after infection, mice developed peritonitis, characterized by high yeast burdens, neutrophil influx, and a pH of 7.9 within peritoneal fluid. Organ invasion by hyphae and early abscess formation were evident 6 and 24 hours after infection, respectively; abscesses resolved by day 14. nanoString assays revealed adhesion and responses to alkaline pH, osmolarity, and stress as biologic processes activated in the peritoneal cavity. Disruption of the highly-expressed gene RIM101, which encodes an alkaline-regulated transcription factor, did not impact cellular morphology but reduced both C. albicans burden during early peritonitis and C. albicans persistence within abscesses. RIM101 influenced expression of 49 genes during intra-abdominal candidiasis, including previously unidentified Rim101 targets. Overexpression of the RIM101-dependent gene SAP5, which encodes a secreted protease, restored the ability of a rim101 mutant to persist within abscesses. Conclusions. A mouse model of intra-abdominal candidiasis is valuable for studying pathogenesis and C. albicans gene expression. RIM101 contributes to persistence within intra-abdominal abscesses, at least in part through activation of SAP5. PMID:24006479

The Improvement of Laparoscopic Surgical Skills Obtained by Gynecologists after Ten Years of Clinical Training Can Reduce Peritoneal Adhesion Formation during Laparoscopic Myomectomy: A Retrospective Cohort Study

PubMed Central

Peiretti, Michele; Minerba, Luigi

2017-01-01

Objective To evaluate if improvement of laparoscopic skills can reduce postoperative peritoneal adhesion formation in a clinical setting. Study Design We retrospectively evaluated 25 women who underwent laparoscopic myomectomy from January 1993 to June 1994 and 22 women who underwent laparoscopic myomectomy from March 2002 to November 2004. Women had one to four subserous/intramural myomas and received surgery without antiadhesive agents or barriers. Women underwent second-look laparoscopy for assessment of peritoneal adhesion formation 12 to 14 weeks after myomectomy. Adhesions were graded according to the Operative Laparoscopy Study Group scoring system. The main variable to be compared between the two cohorts was the proportion that showed no adhesions at second-look laparoscopy. Results Demographic and surgical characteristics were similar between the two cohorts. No complications were observed during surgery. No adverse events were recorded during postoperative course. At second-look laparoscopy, a higher proportion of adhesion-free patients was observed in women who underwent laparoscopic myomectomy from March 2002 to November 2004 (9 out of 22) compared with women who underwent the same surgery from January 1993 to June 1994 (3 out of 25). Conclusion The improvement of surgeons' skills obtained after ten years of surgery can reduce postoperative adhesion formation. PMID:29410967

Kinetic studies of chemical shrinkage and residual stress formation in thermoset epoxy adhesives under confined curing conditions

NASA Astrophysics Data System (ADS)

Schumann, M.; Geiß, P. L.

2015-05-01

Faultless processing of thermoset polymers in demanding applications requires a profound mastering of the curing kinetics considering both the physico-chemical changes in the transition from the liquid to the solid state and the consolidation of the polymers network in the diffusion controlled curing regime past the gel point. Especially in adhesive joints shrinkage stress occurring at an early state of the curing process under confined conditions is likely to cause defects due to local debonding and thus reduce their strength and durability1. Rheometry is considered the method of choice to investigate the change of elastic and viscous properties in the progress of curing. Drawbacks however relate to experimental challenges in accessing the full range of kinetic parameters of thermoset resins with low initial viscosity from the very beginning of the curing reaction to the post-cure consolidation of the polymer due to the formation of secondary chemical bonds. Therefore the scope of this study was to interrelate rheological data with results from in-situ measurements of the shrinkage stress formation in adhesive joints and with the change of refractive index in the progress of curing. This combination of different methods has shown to be valuable in gaining advanced insight into the kinetics of the curing reaction. The experimental results are based on a multi component thermoset epoxy-amine adhesive.

A multicentre, randomised, controlled trial to assess the safety, ease of use, and reliability of hyaluronic acid/carboxymethylcellulose powder adhesion barrier versus no barrier in colorectal laparoscopic surgery.

PubMed

Berdah, Stéphane V; Mariette, Christophe; Denet, Christine; Panis, Yves; Laurent, Christophe; Cotte, Eddy; Huten, Nöel; Le Peillet Feuillet, Eliane; Duron, Jean-Jacques

2014-10-27

Intra-peritoneal adhesions are frequent following abdominal surgery and are the most common cause of small bowel obstructions. A hyaluronic acid/carboxymethylcellulose (HA/CMC) film adhesion barrier has been shown to reduce adhesion formation in abdominal surgery. An HA/CMC powder formulation was developed for application during laparoscopic procedures. This was an exploratory, prospective, randomised, single-blind, parallel-group, Phase IIIb, multicentre study conducted at 15 hospitals in France to assess the safety of HA/CMC powder versus no adhesion barrier following laparoscopic colorectal surgery. Subjects ≥18 years of age who were scheduled for colorectal laparoscopy (Mangram contamination class I‒III) within 8 weeks of selection were eligible, regardless of aetiology. Participants were randomised 1:1 to the HA/CMC powder or no adhesion barrier group using a centralised randomisation list. Patients assigned to HA/CMC powder received a single application of 1 to 10 g on adhesion-prone areas. In the no adhesion barrier group, no adhesion barrier or placebo was applied. The primary safety assessments were the incidence of adverse events, serious adverse events, and surgical site infections (SSIs) for 30 days following surgery. Between-group comparisons were made using Fisher's exact test. Of those randomised to the HA/CMC powder (n = 105) or no adhesion barrier (n = 104) groups, one patient in each group discontinued prior to the study end (one death in each group). Adverse events were more frequent in the HA/CMC powder group versus the no adhesion barrier group (63% vs. 39%; P <0.001), as were serious adverse events (28% vs. 11%; P <0.001). There were no statistically significant differences between the HA/CMC powder group and the no adhesion barrier group in SSIs (21% vs. 14%; P = 0.216) and serious SSIs (12% vs. 9%; P = 0.38), or in the most frequent serious SSIs of pelvic abscess (5% and 2%; significance not tested), anastomotic fistula (3% and 4%), and

Nutritionally Variant Streptococci Interfere with Streptococcus mutans Adhesion Properties and Biofilm Formation.

PubMed

Angius, Fabrizio; Madeddu, Maria Antonietta; Pompei, Raffaello

2015-04-01

The bacterial species Streptococcus mutans is known as the main cause of dental caries in humans. Therefore, much effort has focused on preventing oral colonization by this strain or clearing it from oral tissues. The oral cavity is colonized by several bacterial species that constitute the commensal oral flora, but none of these is able to interfere with the cariogenic properties of S. mutans. This paper describes the interfering ability of some nutritionally variant streptococcal strains (NVS) with S. mutans adhesion to glass surfaces and also to hydroxylapatite. In mixed cultures, NVS induce a complete inhibition of S. mutans microcolony formation on cover glass slides. NVS can also block the adherence of radiolabeled S. mutans to hydroxylapatite in the presence of both saliva and sucrose. The analysis of the action mechanism of NVS demonstrated that NVS are more hydrophobic than S. mutans and adhere tightly to hard surfaces. In addition, a cell-free culture filtrate of NVS was also able to interfere with S. mutans adhesion to hydroxylapatite. Since NVS are known to secrete some important bacteriolytic enzymes, we conclude that NVS can be a natural antagonist to the cariogenic properties of S. mutans.

Adhesive interactions with wood

Treesearch

Charles R. Frihart

2004-01-01

While the chemistry for the polymerization of wood adhesives has been studied systematically and extensively, the critical aspects of the interaction of adhesives with wood are less clearly understood. General theories of bond formation need to be modified to take into account the porosity of wood and the ability of chemicals to be absorbed into the cell wall....

Can tissue adhesives and platelet-rich plasma prevent pharyngocutaneous fistula formation?

PubMed

Eryılmaz, Aylin; Demirci, Buket; Gunel, Ceren; Kacar Doger, Firuzan; Yukselen, Ozden; Kurt Omurlu, Imran; Basal, Yesim; Agdas, Fatih; Basak, Sema

2016-02-01

One of the frequently encountered disorders of wound healing following laryngectomy is pharyngocutaneous fistula. However, although studies have been performed with the aim of prevention of pharyngocutaneous fistulae, there are very few studies with tissue adhesives and platelet-rich plasma. In this study, our aim was to investigate the histopathologic changes in wound healing caused by various tissue adhesives and platelet-rich plasma, together with their effects on prevention of pharyngocutaneous fistula. 40 male rats were randomly divided into five groups: control, platelet-rich plasma, fibrin tissue adhesive, protein-based albumin glutaraldehyde and synthetic tissue adhesive groups. The pharyngotomy procedure was performed and was sutured. Except the control group, tissue adhesives and platelet-rich plasma were applied. Then, the skin was sutured. On the seventh day, the rats were sacrificed. The skin was opened and pharyngotomy site was assessed in terms of fistulae. The pharyngeal suture line was evaluated histopathologically by using Ehrlich Hunt scale. Inflammatory infiltration was found to be higher in "platelet-rich plasma" group than "fibrin tissue adhesive" and "synthetic tissue adhesive" groups. The fibroblastic activity of "platelet-rich plasma", "fibrin tissue adhesive" and "protein-based albumin glutaraldehyde" groups was higher than the control group. The positive changes created by platelet-rich plasma and fibrin tissue adhesive at the histopathologic level were found together with no detected fistula. Among the study groups, there was no statistical difference for pharyngeal fistula development. This result may be obtained by the small number of animal experiments. These results shed light on the suggestion that platelet-rich plasma and fibrin tissue adhesive can be used in clinical studies to prevent pharyngocutaneous fistula. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Evaluation of botulinum toxin type A effectiveness in preventing postoperative intraperitoneal adhesions

PubMed Central

Uysal, Erdal

2017-01-01

Purpose Postoperative intraperitoneal adhesions (PIAs) are one of the most important problems surgeons have to face after laparotomies. In this study, we aimed to evaluate the effectiveness of local application of botulinum toxin type A (BoNT-A) in various dosages on the prevention of intra-abdominal adhesions in rats with experimental intra-abdominal adhesions. Methods Forty Wistar Albino female rats were randomly separated into 4 groups. The 4 groups were determined as follows: Control (group 1, n = 10); Sham (group 2, n = 10); 10-µg/kg low-dose BoNT-A (group 3, n = 10) and 30-µg/kg high-dose BoNT-A (group 4, n = 10). Subserosal injuries were created on the caecum of all rats. Laparotomy was performed on the fifth day. Adhesion scores, histopathological examination, and E-cadherin expression levels were evaluated. Results General adhesion scores for groups 1 and 2 were determined to be significantly high when compared to group 4 (P < 0.001). A significant difference was also determined between groups 3 and 4 in terms of general adhesion scores (P < 0.05). In pair comparisons, a significant decrease in high-dose BoNT-A group (group 4) when compared to groups 1 and 2 in terms of neovascularization, fibroblast density, collagen deposition and inflammatory cell count was determined (P < 0.05). Conclusion A significant decrease was observed only in postoperative PIAs in the high-dose BoNT-A group between all 4 rat-groups with experimentally created postoperative PIAs. In this study, high-dose BoNT-A is determined to be an effective agent in preventing postoperative PIAs. PMID:28706891

Effects of Antiadhesion preparation on free fibrinogen and fibrin degrading products in abdominal exudates of rabbits postoperatively

PubMed Central

Wang, You-Li; Pan, Cheng-En; Yang, Ping-Lin; Tian, Yuan; Pei, Shu-Wen; Dong, Ming

2004-01-01

AIM: To observe effects of ACOL on fibrinogen (FIB), fibrin degrading products (FDP) and changes of FIB and FDP concentration in rabbits with intro-abdominal exudates during 7 d after major abdominal surgery. METHODS: Sixty New Zealand rabbits were randomly divided into 4 groups: ACOL group, the control group, DCT group and the normal group. After being modeled, except the normal group, the other 3 groups were treated with different ways for a week; the intro-abdominal exudates of rabbits in the 4 groups were drawn for FIB and FDP measurement once daily during 7 d after major abdominal surgery. RESULTS: FIB and FDP in the intro-abdominal exudates altered in a regular way and ACOL could change the concentration of FIB and FDP in the intra-abdominal exudates after major abdominal surgery. CONCLUSION: ACOL can prevent intestinal adhesion by reducing the concentration of FIB and raising that of FDP in the intro-abdominal exudates after major abdominal surgery. PMID:15309738

Standard Biocompatibility Studies Do Not Predict All Effects of PVA/CMC Anti-Adhesive Gel in vivo.

PubMed

Freytag, Christiane; Odermatt, Erich K

2016-01-01

PVA/CMC (polyvinyl alcohol/carboxymethyl cellulose) hydrogel fulfills various physiochemical properties required for an adhesion barrier and has shown good anti-adhesion properties in previous in vivo studies. In this investigation, we assessed the in vitro and in vivo biocompatibility of PVA/CMC gel and compared this to the functionality and promotion of wound healing for two surgical indications. Standardized ISO10993 in vitro and in vivo biocompatibility studies, comprising cytotoxicity, genotoxicity, acute systemic toxicity, delayed contact and maximization sensitization test, intracutaneous reactivity and local muscle implantation, were performed on PVA/CMC gel. In the functional studies, PVA/CMC gel was applied - on the one hand - to a rabbit abdominal wall model enforced with a polypropylene mesh for testing the anti-adhesion properties and - on the other hand - to an end- to-end anastomosis model that was selected for surveying potential influences of different dosages of PVA/CMC gel on anastomotic wound healing. The ISO10993 methods indicated generally good biocompatibility properties, such as the absence of cytotoxic and mutagenic effects as well as no signs of systemic toxicity and sensitization potentials. No irritation effects were observed after the intracutaneous injection of lipophilic PVA/CMC sesame oil extract. However, the injection of hydrophilic PVA/CMC physiologic saline extract induced slight irritation. Following rabbit muscle implantation of the PVA membrane for 2, 4, 12, 26 and 52 weeks, a slight irritant effect was observed at 12 weeks due to the peak of phagocytosis. In the functionality tests, PVA/CMC gel showed good anti-adhesive effects in the abdominal wall model enforced with the mesh, with significantly lower and less tense adhesions compared to the untreated control. However, moderate signs of inflammation, especially in the spleen were observed after the intra-abdominal implantation of 3.3 ml PVA/CMC gel per kg body weight. In

The effectiveness of heparin, platelet-rich plasma (PRP), and silver nanoparticles on prevention of postoperative peritoneal adhesion formation in rats.

PubMed

Makarchian, Hamid Reza; Kasraianfard, Amir; Ghaderzadeh, Pezhman; Javadi, Seyed Mohammad Reza; Ghorbanpoor, Manoochehr

2017-01-01

To assess the effectiveness of heparin, platelet-rich plasma (PRP), and silver nanoparticles on prevention of postoperative adhesion in animal models. Sixty males Albino Wistar rats aged 5 to 6 weeks were classified into five groups receiving none, heparin, PRP, silver nanoparticles, PRP plus silver nanoparticles intraperitoneally. After 2 weeks, the animals underwent laparotomy and the damaged site was assessed for peritoneal adhesions severity. The mean severity scores were 2.5 ± 0.9, 2.16 ± 0.7, 1.5 ± 0.5, 2.66 ± 0.88, and 2.25 ± 0.62 in the control, heparin, PRP, silver and PRP plus silver groups, respectively with significant intergroup difference (p = 0.004). The highest effective material for preventing adhesion formation was PRP followed by heparin and PRP plus silver. Moreover, compared to the controls, only use of PRP was significantly effective, in terms of adhesion severity (p = 0.01) . Platelet-rich plasma alone may have the highest efficacy for preventing postoperative peritoneal adhesions in comparison with heparin, silver nanoparticles and PRP plus silver nanoparticles.

PVA gel as a potential adhesion barrier: a safety study in a large animal model of intestinal surgery.

PubMed

Renz, Bernhard W; Leitner, Kurt; Odermatt, Erich; Worthley, Daniel L; Angele, Martin K; Jauch, Karl-Walter; Lang, Reinhold A

2014-03-01

Intra-abdominal adhesions following surgery are a major source of morbidity and mortality including abdominal pain and small bowel obstruction. This study evaluated the safety of PVA gel (polyvinyl alcohol and carboxymethylated cellulose gel) on intestinal anastomoses and its potential effectiveness in preventing adhesions in a clinically relevant large animal model. Experiments were performed in a pig model with median laparotomy and intestinal anastomosis following small bowel resection. The primary endpoint was the safety of PVA on small intestinal anastomoses. We also measured the incidence of postoperative adhesions in PVA vs. control groups: group A (eight pigs): stapled anastomosis with PVA gel compared to group B (eight pigs), which had no PVA gel; group C (eight pigs): hand-sewn anastomosis with PVA gel compared to group B (eight pigs), which had no anti-adhesive barrier. Animals were sacrificed 14 days after surgery and analyzed. All anastomoses had a patent lumen without any stenosis. No anastomoses leaked at an intraluminal pressure of 40 cmH2O. Thus, anastomoses healed very well in both groups, regardless of whether PVA was administered. PVA-treated animals, however, had significantly fewer adhesions in the area of stapled anastomoses. The hand-sewn PVA group also had weaker adhesions and trended towards fewer adhesions to adjacent organs. These results suggest that PVA gel does not jeopardize the integrity of intestinal anastomoses. However, larger trials are needed to investigate the potential of PVA gel to prevent adhesions in gastrointestinal surgery.

Zinc oxide nanoparticles induce migration and adhesion of monocytes to endothelial cells and accelerate foam cell formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suzuki, Yuka; Tada-Oikawa, Saeko; Ichihara, Gaku

Metal oxide nanoparticles are widely used in industry, cosmetics, and biomedicine. However, the effects of exposure to these nanoparticles on the cardiovascular system remain unknown. The present study investigated the effects of nanosized TiO{sub 2} and ZnO particles on the migration and adhesion of monocytes, which are essential processes in atherosclerogenesis, using an in vitro set-up of human umbilical vein endothelial cells (HUVECs) and human monocytic leukemia cells (THP-1). We also examined the effects of exposure to nanosized metal oxide particles on macrophage cholesterol uptake and foam cell formation. The 16-hour exposure to ZnO particles increased the level of monocytemore » chemotactic protein-1 (MCP-1) and induced the migration of THP-1 monocyte mediated by increased MCP-1. Exposure to ZnO particles also induced adhesion of THP-1 cells to HUVECs. Moreover, exposure to ZnO particles, but not TiO{sub 2} particles, upregulated the expression of membrane scavenger receptors of modified LDL and increased cholesterol uptake in THP-1 monocytes/macrophages. In the present study, we found that exposure to ZnO particles increased macrophage cholesterol uptake, which was mediated by an upregulation of membrane scavenger receptors of modified LDL. These results suggest that nanosized ZnO particles could potentially enhance atherosclerogenesis and accelerate foam cell formation. - Highlights: • Effects of metal oxide nanoparticles on foam cell formation were investigated. • Exposure to ZnO nanoparticles induced migration and adhesion of monocytes. • Exposure to ZnO nanoparticles increased macrophage cholesterol uptake. • Expression of membrane scavenger receptors of modified LDL was also increased. • These effects were not observed after exposure to TiO{sub 2} nanoparticles.« less

Atomic force microscopy measurements of bacterial adhesion and biofilm formation onto clay-sized particles

PubMed Central

Huang, Qiaoyun; Wu, Huayong; Cai, Peng; Fein, Jeremy B.; Chen, Wenli

2015-01-01

Bacterial adhesion onto mineral surfaces and subsequent biofilm formation play key roles in aggregate stability, mineral weathering, and the fate of contaminants in soils. However, the mechanisms of bacteria-mineral interactions are not fully understood. Atomic force microscopy (AFM) was used to determine the adhesion forces between bacteria and goethite in water and to gain insight into the nanoscale surface morphology of the bacteria-mineral aggregates and biofilms formed on clay-sized minerals. This study yields direct evidence of a range of different association mechanisms between bacteria and minerals. All strains studied adhered predominantly to the edge surfaces of kaolinite rather than to the basal surfaces. Bacteria rarely formed aggregates with montmorillonite, but were more tightly adsorbed onto goethite surfaces. This study reports the first measured interaction force between bacteria and a clay surface, and the approach curves exhibited jump-in events with attractive forces of 97 ± 34 pN between E. coli and goethite. Bond strengthening between them occurred within 4 s to the maximum adhesion forces and energies of −3.0 ± 0.4 nN and −330 ± 43 aJ (10−18 J), respectively. Under the conditions studied, bacteria tended to form more extensive biofilms on minerals under low rather than high nutrient conditions. PMID:26585552

A nanoporous titanium surface promotes the maturation of focal adhesions and formation of filopodia with distinctive nanoscale protrusions by osteogenic cells.

PubMed

Guadarrama Bello, Dainelys; Fouillen, Aurélien; Badia, Antonella; Nanci, Antonio

2017-09-15

While topography is a key determinant of the cellular response to biomaterials, the mechanisms implicated in the cell-surface interactions are complex and still not fully elucidated. In this context, we have examined the effect of nanoscale topography on the formation of filopodia, focal adhesions, and gene expression of proteins associated with cell adhesion and sensing. Commercially pure titanium discs were treated by oxidative nanopatterning with a solution of H 2 SO 4 /H 2 O 2 50:50 (v/v). Scanning electron microscopy and atomic force microscopy characterizations showed that this facile chemical treatment efficiently creates a unique nanoporous surface with a root-mean-square roughness of 11.5nm and pore diameter of 20±5nm. Osteogenic cells were cultured on polished (control) and nanotextured discs for periods of 6, 24, and 72h. Immunofluorescence analysis revealed increases in the adhesion formation per cell area, focal adhesion length, and maturity on the nanoporous surface. Gene expression for various focal adhesion markers, including paxillin and talin, and different integrins (e.g. α1, β1, and α5) was also significantly increased. Scanning electron microscopy revealed the presence of more filopodia on cells grown on the nanoporous surface. These cell extensions displayed abundant and distinctive nanoscale lateral protrusions of 10-15nm diameter that molded the nanopore walls. Together the increase in the focal adhesions and abundance of filopodia and associated protrusions could contribute to strengthening the adhesive interaction of cells with the surface, and thereby, alter the nanoscale biomechanical relationships that trigger cellular cascades that regulate cell behavior. Oxidative patterning was exploited to create a unique three-dimensional network of nanopores on titanium surfaces. Our study illustrates how a facile chemical treatment can be advantageously used to modulate cellular behavior. The nanoscale lateral protrusions on filopodia

Focal adhesion interactions with topographical structures: a novel method for immuno-SEM labelling of focal adhesions in S-phase cells.

PubMed

Biggs, M J P; Richards, R G; Wilkinson, C D W; Dalby, M J

2008-07-01

Current understanding of the mechanisms involved in osseointegration following implantation of a biomaterial has led to adhesion quantification being implemented as an assay of cytocompatibility. Such measurement can be hindered by intra-sample variation owing to morphological changes associated with the cell cycle. Here we report on a new scanning electron microscopical method for the simultaneous immunogold labelling of cellular focal adhesions and S-phase nuclei identified by BrdU incorporation. Prior to labelling, cellular membranes are removed by tritonization and antigens of non-interest blocked by serum incubation. Adhesion plaque-associated vinculin and S-phase nuclei were both separately labelled with a 1.4 nm gold colloid and visualized by subsequent colloid enhancement via silver deposition. This study is specifically concerned with the effects microgroove topographies have on adhesion formation in S-phase osteoblasts. By combining backscattered electron (BSE) imaging with secondary electron (SE) imaging it was possible to visualize S-phase nuclei and the immunogold-labelled adhesion sites in one energy 'plane' and the underlying nanotopography in another. Osteoblast adhesion to these nanotopographies was ascertained by quantification of adhesion complex formation.

Application of nanosheets as an anti-adhesion barrier in partial hepatectomy.

PubMed

Niwa, Daisuke; Koide, Masatsugu; Fujie, Toshinori; Goda, Nobuhito; Takeoka, Shinji

2013-10-01

Postoperative adhesion often causes serious adverse effects such as bowl obstruction, chronic abdominal pain, pelvic pain, and infertility. We previously reported that a poly-L-lactic acid (PLLA) nanosheet can efficiently seal a surgical incision without scarring. In this report, we examined whether the PLLA nanosheet can form an effective anti-adhesion barrier in partial hepatectomy accompanied by severe hemorrhaging in rats. To evaluate the anti-adhesive property of the nanosheet, the liver wound surface was covered with TachoComb(®) , a well-known hemostat material used in clinical procedures, and then with the PLLA nanosheet. Dressing the wound surface with TachoComb(®) alone caused severe adhesion with omentum and/or residual parts of the liver. By contrast, combinational usage of TachoComb(®) and the PLLA nanosheet significantly reduced such adhesion, presumably by inhibiting the permeation of oozing blood cells and the infiltration of fibroblastic cells. Moreover, the nanosheet displayed low permeability against serum proteins as well as cells in vitro, supporting the notion that the PLLA nanosheet has anti-adhesive properties in vivo. These results strongly suggested that the PLLA nanosheet is a promising material for reducing unwanted postoperative adhesion. Copyright © 2013 Wiley Periodicals, Inc.

Cell-adhesion molecules in memory formation.

PubMed

Schmidt, R

1995-01-23

After learning events the CNS of higher organisms selects, which acquired informations are permanently stored as a memory trace. This period of memory consolidation is susceptible to interference by biochemical inhibitors of transcription and translation. Ependymin is a specific CNS glycoprotein functionally involved in memory consolidation in goldfish: after active shock-avoidance conditioning ependymin mRNA is rapidly induced in meningeal fibroblasts followed by enhanced synthesis and secretion of several closely related forms of the protein. Intracranial injections of anti-ependymin antisera or antisense oligodeoxynucleotides interfere specifically with memory consolidation, indicating that only de novo synthesized ependymin molecules are involved. Ependymin is capable of directing the growth of central axons in vitro and participates in neuronal regeneration in situ, presumably by its HNK-1 cell-adhesion epitope. Experiments reviewed in this article suggest a model that involves two regulation mechanisms for the function of ependymin in behavioural plasticity: while hormones appear to determine, how much of this cell adhesion molecule is synthesized after learning, local changes of metal cation concentrations in the micro-environment of activated neurons may polymerize ependymin at those synapses, that have to be consolidated to improve their efficacy for future use.

Intra-Abdominal Hypertension and Abdominal Compartment Syndrome after Abdominal Wall Reconstruction: Quaternary Syndromes?

PubMed

Kirkpatrick, A W; Nickerson, D; Roberts, D J; Rosen, M J; McBeth, P B; Petro, C C; Berrevoet, Frederik; Sugrue, M; Xiao, Jimmy; Ball, C G

2017-06-01

Reconstruction with reconstitution of the container function of the abdominal compartment is increasingly being performed in patients with massive ventral hernia previously deemed inoperable. This situation places patients at great risk of severe intra-abdominal hypertension and abdominal compartment syndrome if organ failure ensues. Intra-abdominal hypertension and especially abdominal compartment syndrome may be devastating systemic complications with systematic and progressive organ failure and death. We thus reviewed the pathophysiology and reported clinical experiences with abnormalities of intra-abdominal pressure in the context of abdominal wall reconstruction. Bibliographic databases (1950-2015), websites, textbooks, and the bibliographies of previously recovered articles for reports or data relating to intra-abdominal pressure, intra-abdominal hypertension, and the abdominal compartment syndrome in relation to ventral, incisional, or abdominal hernia repair or abdominal wall reconstruction. Surgeons should thus consider and carefully measure intra-abdominal pressure and its resultant effects on respiratory parameters and function during abdominal wall reconstruction. The intra-abdominal pressure post-operatively will be a result of the new intra-peritoneal volume and the abdominal wall compliance. Strategies surgeons may utilize to ameliorate intra-abdominal pressure rise after abdominal wall reconstruction including temporizing paralysis of the musculature either temporarily or semi-permanently, pre-operative progressive pneumoperitoneum, permanently removing visceral contents, or surgically releasing the musculature to increase the abdominal container volume. In patients without complicating shock and inflammation, and in whom the abdominal wall anatomy has been so functionally adapted to maximize compliance, intra-abdominal hypertension may be transient and tolerable. Intra-abdominal hypertension/abdominal compartment syndrome in the specific setting of

Surgical management of intrauterine devices migrated towards intra-abdominal structures: 20-year experience of a tertiary center.

PubMed

Adiyeke, M; Sanci, M; Karaca, I; Gökçü, M; Töz, E; Ocal, E

2015-01-01

To share surgical management experiences of intra-abdominal intrauterine devices (IUDs) in tertiary center. A total of 27 patients were retrospectively analyzed. This retrospective study was conducted between September 1992 and April 2013 at Department of Obstetrics and Gynecology Tepecik Research and Training Hospital, Izmir, Turkey. Demographic findings, diagnostic methods, and operative notes of patients were obtained from the patient file. Of the 27 IUDs, nine (33.3%) were in omentum, four (15%) were in Douglas pouch, one in left sacrouterine ligament, one in uterovesical space and one in fundus posterior, six (22%) in left adnexial region, one in abdominal wall, one was subdiaphragmatic, one in ligamentum latum, and one in jejunum. Almost all of the patients had TCu-380 A IUDs. Seventeen patients (63%) were managed by laparoscopy, whereas laparotomy was required in ten (37%). Adhesions were found in 23 of 27 (85%) patients with varying degrees. In four cases the incision was extended due to adhesions. A missing string was the first finding of an intra-abdominal IUD. Pelvic ultrasonography, X-ray, and hysteroscopy methods should be performed in order to detect the localization of IUD in case of a missing string. Surgical approach should be the first treatment option for intra-abdominal IUDs.

Inhibition of type 1 fimbriae-mediated Escherichia coli adhesion and biofilm formation by trimeric cluster thiomannosides conjugated to diamond nanoparticles

NASA Astrophysics Data System (ADS)

Khanal, Manakamana; Larsonneur, Fanny; Raks, Victoriia; Barras, Alexandre; Baumann, Jean-Sébastien; Martin, Fernando Ariel; Boukherroub, Rabah; Ghigo, Jean-Marc; Ortiz Mellet, Carmen; Zaitsev, Vladimir; Garcia Fernandez, Jose M.; Beloin, Christophe; Siriwardena, Aloysius; Szunerits, Sabine

2015-01-01

Recent advances in nanotechnology have seen the development of a number of microbiocidal and/or anti-adhesive nanoparticles displaying activity against biofilms. In this work, trimeric thiomannoside clusters conjugated to nanodiamond particles (ND) were targeted for investigation. NDs have attracted attention as a biocompatible nanomaterial and we were curious to see whether the high mannose glycotope density obtained upon grouping monosaccharide units in triads might lead to the corresponding ND-conjugates behaving as effective inhibitors of E. coli type 1 fimbriae-mediated adhesion as well as of biofilm formation. The required trimeric thiosugar clusters were obtained through a convenient thiol-ene ``click'' strategy and were subsequently conjugated to alkynyl-functionalized NDs using a Cu(i)-catalysed ``click'' reaction. We demonstrated that the tri-thiomannoside cluster-conjugated NDs (ND-Man3) show potent inhibition of type 1 fimbriae-mediated E. coli adhesion to yeast and T24 bladder cells as well as of biofilm formation. The biofilm disrupting effects demonstrated here have only rarely been reported in the past for analogues featuring such simple glycosidic motifs. Moreover, the finding that the tri-thiomannoside cluster (Man3N3) is itself a relatively efficient inhibitor, even when not conjugated to any ND edifice, suggests that alternative mono- or multivalent sugar-derived analogues might also be usefully explored for E. coli-mediated biofilm disrupting properties.Recent advances in nanotechnology have seen the development of a number of microbiocidal and/or anti-adhesive nanoparticles displaying activity against biofilms. In this work, trimeric thiomannoside clusters conjugated to nanodiamond particles (ND) were targeted for investigation. NDs have attracted attention as a biocompatible nanomaterial and we were curious to see whether the high mannose glycotope density obtained upon grouping monosaccharide units in triads might lead to the corresponding

Regulation of substrate adhesion dynamics during cell motility.

PubMed

Kaverina, Irina; Krylyshkina, Olga; Small, J Victor

2002-07-01

The movement of a metazoan cell entails the regulated creation and turnover of adhesions with the surface on which it moves. Adhesion sites form as a result of signaling between the extracellular matrix on the outside and the actin cytoskeleton on the inside, and they are associated with specific assembles of actin filaments. Two broad categories of adhesion sites can be distinguished: (1) "focal complexes" associated with lamellipodia and filopodia that support protrusion and traction at the cell front; and (2) "focal adhesions" at the termini of stress fibre bundles that serve in longer term anchorage. Focal complexes are signaled via Rac1 or Cdc42 and can either turnover on a minute scale or differentiate, via intervention of the RhoA pathway, into longer-lived focal adhesions. All classes of adhesion sites depend on the stress in the actin cytoskeleton for their formation and maintenance. Different cell types use different adhesion strategies to move, in terms of the relative engagement of filopodia and lamellipodia in focal complex formation and protrusion and the extent of focal adhesion formation. These differences can be attributed to variations in the relative activities of Rho family members. However, the Rho GTPases alone are unable to signal asymmetry in the actin cytoskeleton, necessary for polarisation and movement. Polarisation requires the collaboration of the microtubule cytoskeleton. Changes in the polymerisation state of microtubules influences the activities of both Rac1 and RhoA and microtubules interact directly with adhesion foci and promote their turnover. Possible mechanisms of cross-talk between the microtubule and actin cytoskeletons in determining polarity are discussed.

Morphological Evaluation of the Adhesive/Enamel interfaces of Two-step Self-etching Adhesives and Multimode One-bottle Self-etching Adhesives.

PubMed

Sato, Takaaki; Takagaki, Tomohiro; Matsui, Naoko; Hamba, Hidenori; Sadr, Alireza; Nikaido, Toru; Tagami, Junji

To evaluate the acid-base resistant zone (ABRZ) at the adhesive/enamel interface of self-etching adhesives with or without prior phosphoric acid etching. Four adhesives were used in 8 groups: Clearfil SE Bond (SEB), Optibond XTR (XTR), Scotchbond Universal Adhesive (SBU), and Clearfil BOND SE ONE (ONE) without prior phosphoric-acid etching, and each adhesive with phosphoric acid etching for 10 s (P-SEB, P-XTR, P-SBU and P-ONE, respectively). After application of self-etching adhesives on ground enamel surfaces of human teeth, a flowable composite was placed. For observation of the acid-base resistant zone (ABRZ), the bonded interface was exposed to demineralizing solution (pH 4.5) for 4.5 h, followed by 5% NaOCl with ultrasonication for 20 min. After the acid-base challenge, morphological attributes of the interface were observed using SEM. ABRZ formation was confirmed in all groups. The funnel-shaped erosion beneath the interface was present in SBU and ONE, where nearly 10 to 15 μm of enamel was dissolved. With phosphoric acid etching, the ABRZs were obviously thicker compared with no phosphoric acid etching. Enamel beneath the bonding interface was more susceptible to acid dissolution in SBU and ONE. In the case of the one-bottle self-etching adhesives and universal adhesives that intrinsically have higher pH values, enamel etching should be recommended to improve the interfacial quality.

Membrane adhesion and the formation of heterogeneities: biology, biophysics, and biotechnology

PubMed Central

Gordon, V. D.; O’Halloran, T.J.; Shindell, O.

2015-01-01

Membrane adhesion is essential to many vital biological processes. Sites of membrane adhesion are often associated with heterogeneities in the lipid and protein composition of the membrane. These heterogeneities are thought to play functional roles by facilitating interactions between proteins. However, the causal links between membrane adhesion and membrane heterogeneities are not known. Here we survey the state of the field and indicate what we think are understudied areas ripe for development. PMID:25866854

Membrane adhesion and the formation of heterogeneities: biology, biophysics, and biotechnology.

PubMed

Gordon, V D; O'Halloran, T J; Shindell, O

2015-06-28

Membrane adhesion is essential to many vital biological processes. Sites of membrane adhesion are often associated with heterogeneities in the lipid and protein composition of the membrane. These heterogeneities are thought to play functional roles by facilitating interactions between proteins. However, the causal links between membrane adhesion and membrane heterogeneities are not known. Here we survey the state of the field and indicate what we think are understudied areas ripe for development.

Use of 2-octyl cyanoacrylate adhesive in rat liver induced lesion.

PubMed

Santos, Orlando José dos; Marques, Giancarlo de Souza; Sauaia Filho, Euler Nicolau; Frota, Gustavo Medeiros; Santos, Rayan Haquim Pinheiro; Santos, Rennan Abud Pinheiro

2012-09-01

To evaluate the healing process of rat traumatic liver lesion corrected with the use of 2-octyl cyanoacrylate adhesive, compared to the use of biologically absorbable chromed catgut thread suture. Thirty mail adult rats were divided into two groups (15 per group) according to the used method for liver lesion correction as follows: adhesive group (AG), and catgut group (CG); each group being divided into three subsets of five animals (7th, 14th, and 21st day), respectively, according to post-surgery evaluation. All animals were submitted to homogeneous lesion applying synthetic bonding to AG and using chromed catgut suture to CG for lesion correction. Macroscopic and microscopic parameters of healing processes were evaluated. Both groups of animals showed excellent abdominal wall healing, with no evidence of infection, and no abdominal cavity peritonitis or abscess. The presence of adherence was observed in both groups with no statistically significant difference. As to macroscopic evaluation, there was statistically significant difference with respect to specific factors of clinical inflammation (ischemic inflammation and giant celular inflammatory reaction) between animals evaluated on the 10th day (ischemic necrosis and giant cellular inflammatory reaction) among animals evaluated on the 14th day (A14 versus C14). Applying 2-octyl-cyanoacrylate adhesive for correcting rat liver lesion does not change healing process when compared to the use of chromed catgut stitch.

Intraperitoneal adhesions--an ongoing challenge between biomedical engineering and the life sciences.

PubMed

Brochhausen, Christoph; Schmitt, Volker H; Rajab, Taufiek K; Planck, Constanze N E; Krämer, Bernhard; Wallwiener, Markus; Hierlemann, Helmut; Kirkpatrick, C James

2011-07-01

Peritoneal adhesions remain a relevant clinical problem despite the currently available prophylactic barrier materials. So far, the physical separation of traumatized serosa areas using barriers represents the most important clinical strategy for adhesion prevention. However, the optimal material has not yet been found. Further optimization or pharmacological functionalization of these barriers could give an innovative input for peritoneal adhesion prevention. Therefore, a more complete understanding of pathogenesis is required. On the basis of the pathophysiology of adhesion formation the main barriers currently in clinical practice as well as new innovations are discussed in the present review. Physiologically, mesothelial cells play a decisive role in providing a frictionless gliding surface on the serosa. Adhesion formation results from a cascade of events and is regulated by a variety of cellular and humoral factors. The main clinically applied strategy for adhesion prevention is based on the use of liquid or solid adhesion barriers to separate physically any denuded tissue. Both animal and human trials have not yet been able to identify the optimal barrier to prevent adhesion formation in a sustainable way. Therefore, further developments are required for effective prevention of postoperative adhesion formation. To reach this goal the combination of structural modification and pharmacological functionalization of barrier materials should be addressed. Achieving this aim requires the interaction between basic research, materials science and clinical expertise. Copyright © 2011 Wiley Periodicals, Inc.

Nanofiber mats composed of a chitosan-poly(d,l-lactic-co-glycolic acid)-poly(ethylene oxide) blend as a postoperative anti-adhesion agent.

PubMed

Ko, Jae Eok; Ko, Young-Gwang; Kim, Won Il; Kwon, Oh Kyoung; Kwon, Oh Hyeong

2017-10-01

Postoperative tissue adhesion causes serious complications and suffering in 90% of patients after peritoneum surgery, while commercial anti-adhesion agents cannot completely prevent postoperative peritoneal adhesions. This study demonstrates electrospining of a blended solution of chitosan, poly(d,l-lactic-co-glycolic acid) (PLGA), and poly(ethylene oxide) (PEO) to fabricate a chitosan-based nanofibrous mat as a postoperative anti-adhesion agent. Rheological studies combined with scanning electron microscopy reveal that the spinnability of the chitosan-PLGA solution could be controlled by adjusting the blend ratio and concentration with average fiber diameter from 634 to 913 nm. Biodegradation of the nanofiber specimens showed accelerated hydrolysis by chitosan. Proliferation of fibroblasts and antimicrobial activity of nanofibers containing chitosan was analyzed. Abdominal defects with cecum adhesion in rats demonstrated that the blend nanofiber mats were effective in preventing tissue adhesion as a barrier (4 weeks after abdominal surgery) by coverage of exfoliated peritoneum and insufficient wound sites at the beginning of the wound healing process. Chitosan-PLGA-PEO blend nanofiber mats will provide a promising key as a postoperative anti-adhesion agent. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1906-1915, 2017. © 2016 Wiley Periodicals, Inc.

Effect of antibacterial dental adhesive on multispecies biofilms formation.

PubMed

Zhang, K; Wang, S; Zhou, X; Xu, H H K; Weir, M D; Ge, Y; Li, M; Wang, S; Li, Y; Xu, X; Zheng, L; Cheng, L

2015-04-01

Antibacterial adhesives have favorable prospects to inhibit biofilms and secondary caries. The objectives of this study were to investigate the antibacterial effect of dental adhesives containing dimethylaminododecyl methacrylate (DMADDM) on different bacteria in controlled multispecies biofilms and its regulating effect on development of biofilm for the first time. Antibacterial material was synthesized, and Streptococcus mutans, Streptococcus gordonii, and Streptococcus sanguinis were chosen to form multispecies biofilms. Lactic acid assay and pH measurement were conducted to study the acid production of controlled multispecies biofilms. Anthrone method and exopolysaccharide (EPS):bacteria volume ratio measured by confocal laser scanning microscopy were performed to determine the EPS production of biofilms. The colony-forming unit counts, scanning electron microscope imaging, and dead:live volume ratio decided by confocal laser scanning microscopy were used to study the biomass change of controlled multispecies biofilms. The TaqMan real-time polymerase chain reaction and fluorescent in situ hybridization imaging were used to study the proportion change in multispecies biofilms of different groups. The results showed that DMADDM-containing adhesive groups slowed the pH drop and decreased the lactic acid production noticeably, especially lactic acid production in the 5% DMADDM group, which decreased 10- to 30-fold compared with control group (P < 0.05). EPS was reduced significantly in 5% DMADDM group (P < 0.05). The DMADDM groups reduced the colony-forming unit counts significantly (P < 0.05) and had higher dead:live volume ratio in biofilms compared with control group (P < 0.05). The proportion of S. mutans decreased steadily in DMADDM-containing groups and continually increased in control group, and the biofilm had a more healthy development tendency after the regulation of DMADDM. In conclusion, the adhesives containing DMADDM had remarkable antimicrobial

Indicators for surgery in adhesive bowel obstruction.

PubMed

Rajanikmanth, P V; Kate, V; Ananthakrishnan, N

2001-01-01

There is lack of data on risk factors, which, if present, would indicate the need for surgery in patients with adhesive bowel obstruction. A Cohort of 100 consecutive patients with adhesive obstruction was studied prospectively to compare clinical and investigative parameters between the operative and conservative group. It was found that female gender, previous obstetric or gynaecological procedures, pulse and BP on admission, nature of nasogastric aspirate, single distended loop on abdominal x-ray as also predominant ileal distension were independent factors indicating a high probability of surgical intervention. Patients with 2 or more risk factors had 12 times higher probability of surgery and in those with 3 or more the relative risk was 30 times. Patients with such risk factors should be monitored closely after admission and should be taken for surgery after an initial short trial of conservative measures.

Prevention of Pleural Adhesions by Bioactive Polypeptides - A Pilot Study

PubMed Central

Åkerberg, D.; Posaric-Bauden, M.; Isaksson, K.; Andersson, R.; Tingstedt, B.

2013-01-01

Objective: Postoperative pleural adhesions lead to major problems in repeated thoracic surgery. To date, no antiadhesive product has been proven clinically effective. Previous studies of differently charged polypeptides, poly-L-lysine (PL) and poly-L-glutamate (PG) have shown promising results reducing postoperative abdominal adhesions in experimental settings. This pilot study examined the possible pleural adhesion prevention by using the PL+PG concept after pleural surgery and its possible effect on key parameters; plasmin activator inhibitor-1 (PAI-1) and tissue growth factor beta 1 (TGFb) in the fibrinolytic process. Methods: A total of 22 male rats were used in the study, one control group (n=10) and one experimental group (n=12). All animals underwent primary pleural surgery, the controls receiving saline in the pleural cavity and the experimental group the PL+PG solution administered by spray. The animals were evaluated on day 7. Macroscopic appearance of adhesions was evaluated by a scoring system. Histology slides of the adhesions and pleural biopsies for evaluation of PAI-1 and TGFb1 were taken on day 7. Results: A significant reduction of adhesions in the PL+PG group (p<0.05) was noted at day 7 both regarding the length and severity of adhesions. There were no significant differences in the concentration of PAI-1 and TGFb1 when comparing the two groups. Conclusions: PL+PG may be used to prevent pleural adhesions. The process of fibrinolysis, and fibrosis was though not affected after PLPG administration. PMID:24151443

Synergistic Effect of Combined Hollow Viscus Injuries on Intra-Abdominal Abscess Formation.

PubMed

Paulus, Elena M; Croce, Martin A; Shahan, Charles P; Zarzaur, Ben L; Sharpe, John P; Dileepan, Amirtha; Boyd, Brandon S; Fabian, Timothy C

2015-07-01

The strong association between penetrating colon injuries and intra-abdominal abscess (IAA) formation is well established and attributed to high colon bacterial counts. Since trauma patients are rarely fasting at injury, stomach and small bowel colony counts are also elevated. We hypothesized that there is a synergistic effect of increased IAA formation with concomitant stomach and/or colon injuries when compared to small bowel injuries alone. Consecutive patients at a level one trauma center with penetrating small bowel (SB), stomach (S), and/or colon (C) injuries from 1996 to 2012 were reviewed. Logistic regression determined associations with IAA, adjusting for age, gender, Injury Severity Score (ISS), admission Glasgow Coma Score, transfusions, and concurrent pancreas or liver injury. A total of 1518 patients (91% male, ISS = 15.9 ± 8.4) were identified: 496 (33%) SB, 231 (15%) S, 288 (19%) C, 40 (3%) S + SB, 69 (5%) S + C, 338 (22%) C + SB, and 56 (4%) S + C + SB. 148 (10%) patients developed IAA: 4 per cent SB, 9 per cent S, 10 per cent C, 5 per cent S + SB, 22 per cent S + C, 13 per cent C + SB, and 25 per cent S + C + SB. Multiple logistic regression demonstrated that ISS, 24 hour blood transfusions, and concomitant pancreatic or liver injuries were associated with IAA. Compared with reference SB, S or S + SB injuries were no more likely to develop IAA. However, S + C, SB + C, and S + C + SB injuries were significantly more likely to have IAA. In conclusion, combined stomach + colon, small bowel + colon, and stomach, colon, + small bowel injuries have a synergistic effect leading to increased IAA formation after penetrating injuries. Heightened clinical suspicion for IAA formation is necessary in these combined hollow viscus injury patients.

Safety and Efficacy of Alginate Adhesion Barrier Gel in Compromised Intestinal Anastomosis.

PubMed

Chaturvedi, Ankit A; Yauw, Simon T K; Lomme, Roger M L M; Hendriks, Thijs; van Goor, Harry

For any anti-adhesive barrier developed for abdominal surgery, the use under conditions in which anastomotic healing is compromised needs to be investigated. The current study evaluates the effect of a new ultrapure alginate gel on early healing of high-risk anastomoses in the ileum and compares this with the gold standard used in clinical practice. In 75 adult male Wistar rats, a 5 mm ileal segment was resected and continuity was restored by construction of an inverted anastomosis. Rats were divided randomly into a control group and groups receiving either alginate gel or a sodium hyaluronate carboxymethylcellulose (HA/CMC) film around the anastomosis (n = 25 each). Carprofen, given in a daily dose of 1.25 mg/kg, was used to compromise anastomotic healing. At day three, animals were killed and scored for signs of anastomotic leakage and the presence of adhesions. The incidence of adhesion formation was 95% in the HA/CMC film group, which was significantly higher than in the controls (64%, p = 0.010) and the alginate gel group (52%, p = 0.004). The adhesion score was nearly 40% lower in the alginate gel group compared with the HA/CMC film group. The incidence of ileal leakage in the HA/CMC film group (92%) was significantly higher than in the controls (68%, p = 0.016). Leakage rate did not differ between the alginate gel and control groups. There was no significant difference between groups in either incision bursting pressure or incision breaking strength. Ultrapure alginate gel does not interfere with repair of ileal anastomoses constructed under conditions in which chances of anastomotic dehiscence are high. The alginate gel performs better than the HA/CMC film.

A randomized controlled experimental study of the efficacy of platelet-rich plasma and hyaluronic acid for the prevention of adhesion formation in a rat uterine horn model.

PubMed

Oz, Murat; Cetinkaya, Nilufer; Bas, Sevda; Korkmaz, Elmas; Ozgu, Emre; Terzioglu, Gokay Serdar; Buyukkagnici, Umran; Akbay, Serap; Caydere, Muzaffer; Gungor, Tayfun

2016-09-01

Platelet-rich plasma (PRP) has been known to possess an efficacy in tissue regeneration. The aim of this study was to determine the role of PRP on post-operative adhesion formation in an experimental rat study. Thirty Sprague-Dawley rats were randomly divided into control, hyaluronic acid, and PRP treatment groups and operated on for uterine horn adhesion modeling. Blood was collected to produce a PRP with platelet counts of 688 × 10(3)/μL, and 1 ml of either hyaluronic acid gel or PRP was administered over the standard lesions, while the control group received no medication. The evaluation of post-operative adhesions was done on the 30th post-operative day. The location, extent, type, and tenacity of adhesions as well as total adhesion scores, tissue inflammation, fibrosis and transforming growth factor-1beta (TGF-1β) expressions were evaluated. The total adhesion score was significantly lower in the PRP group (3.2 ± 1.5) compared with the hyaluronic acid (5.0 ± 1.3) and control (8.1 ± 1.7) groups. The extent of the adhesions was significantly lower in the PRP group. There was no significant difference in the type and tenacity of adhesions between the hyaluronic acid and the PRP group. The level of inflammation was significantly higher in the control group than the others, while there was no difference between the PRP and hyaluronic acid groups. TGF-1β expression was significantly lesser in the PRP group than the control and hyaluronic acid groups. PRP is more effective than hyaluronic acid treatment in preventing post-operative adhesion formation in an experimental rat uterine horn adhesion model.

Predicting adhesion and biofilm formation boundaries on stainless steel surfaces by five Salmonella enterica strains belonging to different serovars as a function of pH, temperature and NaCl concentration.

PubMed

Moraes, Juliana O; Cruz, Ellen A; Souza, Enio G F; Oliveira, Tereza C M; Alvarenga, Verônica O; Peña, Wilmer E L; Sant'Ana, Anderson S; Magnani, Marciane

2018-05-26

This study aimed to assess the capability of 97 epidemic S. enterica strains belonging to 18 serovars to form biofilm. Five strains characterized as strong biofilm-producers, belonging to distinct serovars (S. Enteritidis 132, S. Infantis 176, S. Typhimurium 177, S. Heidelberg 281 and S. Corvallis 297) were assayed for adhesion/biofilm formation on stainless steel surfaces. The experiments were conducted in different combinations of NaCl (0, 2, 4, 5, 6, 8 and 10% w/v), pH (4, 5, 6 and 7) and temperatures (8 °C, 12 °C, 20 °C and 35 °C). Only adhesion was assumed to occur when S. enterica counts were ≥3 and <5 log CFU/cm 2 , whereas biofilm formation was defined as when the counts were ≥5 log CFU/cm 2 . The binary responses were used to develop models to predict the probability of adhesion/biofilm formation on stainless steel surfaces by five strains belonging to different S. enterica serovars. A total of 99% (96/97) of the tested S. enterica strains were characterized as biofilm-producers in the microtiter plate assays. The ability to form biofilm varied (P < 0.05) within and among the different serovars. Among the biofilm-producers, 21% (20/96), 45% (43/96), and 35% (34/96) were weak, moderate and strong biofilm-producers, respectively. The capability for adhesion/biofilm formation on stainless steel surfaces under the experimental conditions studied varied among the strains studied, and distinct secondary models were obtained to describe the behavior of the five S. enterica tested. All strains showed adhesion at pH 4 up to 4% of NaCl and at 20 °C and 35 °C. The probability of adhesion decreased when NaCl concentrations were >8% and at 8 °C, as well as in pH values ≤ 5 and NaCl concentrations > 6%, for all tested strains. At pH 7 and 6, biofilm formation for S. Enteritidis, S. Infantis, S. Typhimurium, S. Heidelberg was observed up to 6% of NaCl at 35 °C and 20 °C. The predicted boundaries for adhesion were p

Oral traditional Chinese medication for adhesive small bowel obstruction.

PubMed

Suo, Tao; Gu, Xixi; Andersson, Roland; Ma, Huaixing; Zhang, Wei; Deng, Wei; Zhang, Boheng; Cai, Dingfang; Qin, Xinyu

2012-05-16

Small bowel obstruction (SBO) is one of the most common emergent complications of general surgery. Intra-abdominal adhesions are the leading cause of SBO. Because surgery can induce new adhesions, non-operative management is preferred in the absence of signs of peritonitis or strangulation. Oral traditional Chinese herbal medicine has long been used as a non-operative therapy to treat adhesive SBO in China. Many controlled trials have been conducted to investigate its therapeutic value in resolving adhesive SBO. The aim of this review was to assess the efficacy and safety of oral traditional Chinese medicine (TCM) for adhesive small bowel obstruction. We searched the following databases, without regard to language or publishing restrictions: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Chinese Biomedical Database (CBM), China National Knowledge Infrastructure/Chinese Academic Journals full-text Database (CNKI), and VIP (a full-text database of Chinese journals). The searches were conducted in November 2011. Randomised controlled trials and quasi-randomised controlled trials comparing Chinese medicines administered orally, via the gastric canal, or both with a placebo or conventional therapy in participants diagnosed with adhesive SBO were considered. We also considered trials of TCM (oral administration, gastric tube perfusion, or both) plus conventional therapy compared with conventional therapy alone for patients with adhesive SBO. Studies addressing the safety and efficacy of oral traditional Chinese medicinal agents in the treatment of adhesive SBO were also considered. Two authors collected the data independently. We assessed the risk of bias according to the following methodological criteria: random sequence generation, allocation concealment, blinding, incomplete outcome data, selective outcome reporting and other sources of bias. Dichotomous data are presented as risk ratios (OR) and 95% confidence intervals (CI

Effect of oxiplex* films (PEO/CMC) on adhesion formation and reformation in rabbit models and on peritoneal infection in a rat model.

PubMed

Rodgers, K E; Schwartz, H E; Roda, N; Thornton, M; Kobak, W; diZerega, G S

2000-04-01

To assess the efficacy of Oxiplex (FzioMed, Inc., San Luis Obispo, CA) barriers. Film of polyethylene oxide and carboxymethylcellulose (Oxiplex) were tested for strength and tissue adherence. Films were selected for evaluation in models for biocompatability and adherence. Three films were selected for evaluation in efficacy studies, and one was evaluated for effects on bacterial peritonitis. Handling characteristics of Oxiplex film were evaluated via laparoscopy. University laboratory. Rabbits, rats, pigs. Placement of Oxiplex prototypes at the site of injury. Mechanical properties, biocompatibility, tissue adherence, adhesion development, infection potentiation, and device handling. Mechanical tests indicated that tensile strength and elongation were inversely correlated. All films tested had excellent tissue adherence properties. Selected films, based on residence time and biocompatibility, prevented adhesion formation in all animals and were highly efficacious in preventing adhesion reformation. The optimal Oxiplex prototype prevented adhesion reformation in 91% of the animals. This Oxiplex film, dyed to allow visualization, prevented adhesion reformation and did not affect bacterial peritonitis. In a laparoscopic model, the Oxiplex film, delivered in FilmSert forceps, via a 5.0-mm trocar, rapidly unfurled and could be easily applied to tissue with strong adherence. These data show development of an adhesion prevention material that is tissue adherent, can be placed via laparoscopy, and does not affect host resistance.

Tannins Possessing Bacteriostatic Effect Impair Pseudomonas aeruginosa Adhesion and Biofilm Formation

PubMed Central

Trentin, Danielle S.; Silva, Denise B.; Amaral, Matheus W.; Zimmer, Karine R.; Silva, Márcia V.; Lopes, Norberto P.; Giordani, Raquel B.; Macedo, Alexandre J.

2013-01-01

Plants produce many compounds that are biologically active, either as part of their normal program of growth and development or in response to pathogen attack or stress. Traditionally, Anadenanthera colubrina, Commiphora leptophloeos and Myracrodruon urundeuva have been used by communities in the Brazilian Caatinga to treat several infectious diseases. The ability to impair bacterial adhesion represents an ideal strategy to combat bacterial pathogenesis, because of its importance in the early stages of the infectious process; thus, the search for anti-adherent compounds in plants is a very promising alternative. This study investigated the ability of stem-bark extracts from these three species to control the growth and prevent biofilm formation of Pseudomonas aeruginosa, an important opportunistic pathogen that adheres to surfaces and forms protective biofilms. A kinetic study (0–72 h) demonstrated that the growth of extract-treated bacteria was inhibited up to 9 h after incubation, suggesting a bacteriostatic activity. Transmission electron microscopy and fluorescence microscopy showed both viable and nonviable cells, indicating bacterial membrane damage; crystal violet assay and scanning electron microscopy demonstrated that treatment strongly inhibited biofilm formation during 6 and 24 h and that matrix production remained impaired even after growth was restored, at 24 and 48 h of incubation. Herein, we propose that the identified (condensed and hydrolyzable) tannins are able to inhibit biofilm formation via bacteriostatic properties, damaging the bacterial membrane and hindering matrix production. Our findings demonstrate the importance of this abundant class of Natural Products in higher plants against one of the most challenging issues in the hospital setting: biofilm resilience. PMID:23776646

Inhibition of type 1 fimbriae-mediated Escherichia coli adhesion and biofilm formation by trimeric cluster thiomannosides conjugated to diamond nanoparticles.

PubMed

Khanal, Manakamana; Larsonneur, Fanny; Raks, Victoriia; Barras, Alexandre; Baumann, Jean-Sébastien; Martin, Fernando Ariel; Boukherroub, Rabah; Ghigo, Jean-Marc; Ortiz Mellet, Carmen; Zaitsev, Vladimir; Garcia Fernandez, Jose M; Beloin, Christophe; Siriwardena, Aloysius; Szunerits, Sabine

2015-02-14

Recent advances in nanotechnology have seen the development of a number of microbiocidal and/or anti-adhesive nanoparticles displaying activity against biofilms. In this work, trimeric thiomannoside clusters conjugated to nanodiamond particles (ND) were targeted for investigation. NDs have attracted attention as a biocompatible nanomaterial and we were curious to see whether the high mannose glycotope density obtained upon grouping monosaccharide units in triads might lead to the corresponding ND-conjugates behaving as effective inhibitors of E. coli type 1 fimbriae-mediated adhesion as well as of biofilm formation. The required trimeric thiosugar clusters were obtained through a convenient thiol-ene "click" strategy and were subsequently conjugated to alkynyl-functionalized NDs using a Cu(I)-catalysed "click" reaction. We demonstrated that the tri-thiomannoside cluster-conjugated NDs (ND-Man3) show potent inhibition of type 1 fimbriae-mediated E. coli adhesion to yeast and T24 bladder cells as well as of biofilm formation. The biofilm disrupting effects demonstrated here have only rarely been reported in the past for analogues featuring such simple glycosidic motifs. Moreover, the finding that the tri-thiomannoside cluster (Man3N3) is itself a relatively efficient inhibitor, even when not conjugated to any ND edifice, suggests that alternative mono- or multivalent sugar-derived analogues might also be usefully explored for E. coli-mediated biofilm disrupting properties.

Direct Loading and Tunable Release of Antibiotics from Polyelectrolyte Multilayers To Reduce Bacterial Adhesion and Biofilm Formation.

PubMed

Wang, Bailiang; Jin, Tingwei; Xu, Qingwen; Liu, Huihua; Ye, Zi; Chen, Hao

2016-05-18

Bacteria adhesion on the surface of biomaterials and following biofilm formation are important problems in biomedical applications. The charged antibiotics with small molar mass can hardly deposit alternately with polymers into multilayered films to load the drug. Herein, the (poly(acrylic acid)-gentamicin/poly(ethylenimine))n ((PAA-GS/PEI)n) multilayer film was designed and constructed via a layer-by-layer self-assembly method. Low molar mass GS cations were first combined with polyanion PAA and self-assembled with PEI to form multilayer films showing exponential growth behavior. The GS dosage could be adjusted by changing the layer number of films. Furthermore, the thermal cross-linking method was used to control the release rate of GS in PBS buffer. Owing to the diffusion of GS, a zone of inhibition of about 7.0 mm showed the efficient disinfection activity of the multilayer film. It could also be seen from the biofilm inhibition assay that the multilayer film effectively inhibited bacterial adhesion and biofilm formation. As the drug loading dosage was 160 μg/cm(2), the multilayer films showed very low cytotoxicity against human lens epithelial cells. The present work provides an easy way to load GS into multilayer films which can be applied to surface modification of implants and biomedical devices.

Mussel adhesion – essential footwork

PubMed Central

2017-01-01

ABSTRACT Robust adhesion to wet, salt-encrusted, corroded and slimy surfaces has been an essential adaptation in the life histories of sessile marine organisms for hundreds of millions of years, but it remains a major impasse for technology. Mussel adhesion has served as one of many model systems providing a fundamental understanding of what is required for attachment to wet surfaces. Most polymer engineers have focused on the use of 3,4-dihydroxyphenyl-l-alanine (Dopa), a peculiar but abundant catecholic amino acid in mussel adhesive proteins. The premise of this Review is that although Dopa does have the potential for diverse cohesive and adhesive interactions, these will be difficult to achieve in synthetic homologs without a deeper knowledge of mussel biology; that is, how, at different length and time scales, mussels regulate the reactivity of their adhesive proteins. To deposit adhesive proteins onto target surfaces, the mussel foot creates an insulated reaction chamber with extreme reaction conditions such as low pH, low ionic strength and high reducing poise. These conditions enable adhesive proteins to undergo controlled fluid–fluid phase separation, surface adsorption and spreading, microstructure formation and, finally, solidification. PMID:28202646

Adhesion and formation of microbial biofilms in complex microfluidic devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumar, Aloke; Karig, David K; Neethirajan, Suresh

2012-01-01

Shewanella oneidensis is a metal reducing bacterium, which is of interest for bioremediation and clean energy applications. S. oneidensis biofilms play a critical role in several situations such as in microbial energy harvesting devices. Here, we use a microfluidic device to quantify the effects of hydrodynamics on the biofilm morphology of S. oneidensis. For different rates of fluid flow through a complex microfluidic device, we studied the spatiotemporal dynamics of biofilms, and we quantified several morphological features such as spatial distribution, cluster formation and surface coverage. We found that hydrodynamics resulted in significant differences in biofilm dynamics. The baffles inmore » the device created regions of low and high flow in the same device. At higher flow rates, a nonuniform biofilm develops, due to unequal advection in different regions of the microchannel. However, at lower flow rates, a more uniform biofilm evolved. This depicts competition between adhesion events, growth and fluid advection. Atomic force microscopy (AFM) revealed that higher production of extra-cellular polymeric substances (EPS) occurred at higher flow velocities.« less

Telomerase deficiency in bone marrow-derived cells attenuates angiotensin II-induced abdominal aortic aneurysm formation.

PubMed

Findeisen, Hannes M; Gizard, Florence; Zhao, Yue; Cohn, Dianne; Heywood, Elizabeth B; Jones, Karrie L; Lovett, David H; Howatt, Deborah A; Daugherty, Alan; Bruemmer, Dennis

2011-02-01

Abdominal aortic aneurysms (AAA) are an age-related vascular disease and an important cause of morbidity and mortality. In this study, we sought to determine whether the catalytic component of telomerase, telomerase reverse transcriptase (TERT), modulates angiotensin (Ang) II-induced AAA formation. Low-density lipoprotein receptor-deficient (LDLr-/-) mice were lethally irradiated and reconstituted with bone marrow-derived cells from TERT-deficient (TERT-/-) mice or littermate wild-type mice. Mice were placed on a diet enriched in cholesterol, and AAA formation was quantified after 4 weeks of Ang II infusion. Repopulation of LDLr-/- mice with TERT-/- bone marrow-derived cells attenuated Ang II-induced AAA formation. TERT-deficient recipient mice revealed modest telomere attrition in circulating leukocytes at the study end point without any overt effect of the donor genotype on white blood cell counts. In mice repopulated with TERT-/- bone marrow, aortic matrix metalloproteinase-2 (MMP-2) activity was reduced, and TERT-/- macrophages exhibited decreased expression and activity of MMP-2 in response to stimulation with Ang II. Finally, we demonstrated in transient transfection studies that TERT overexpression activates the MMP-2 promoter in macrophages. TERT deficiency in bone marrow-derived macrophages attenuates Ang II-induced AAA formation in LDLr-/- mice and decreases MMP-2 expression. These results point to a previously unrecognized role of TERT in the pathogenesis of AAA.

Segmental jejunal entrapment, volvulus, and strangulation secondary to intra-abdominal adhesions in a dog.

PubMed

Di Cicco, Michael F; Bennett, R Avery; Ragetly, Chantal; Sippel, Kate M

2011-01-01

A 4 yr old, castrated male dachshund was presented for lethargy, restlessness, a "hunched" posture, and a painful abdomen. A gastric foreign body had been surgically removed 24 mo previously. Exploratory celiotomy revealed a devitalized segment of jejunum with twisted mesentery. Several adhesions and fibrous bands were present within the abdomen, presumptively from the previous gastric foreign body surgery. Histopathology determined that a fibrous tissue band caused entrapment of the segment of intestine and its mesentery resulting in volvulus and ischemic necrosis of the intestine. This case is unique because it involved a focal area of the jejunum that was incarcerated in fibrous adhesions.

The preventive effect of Daikenchuto on postoperative adhesion-induced intestinal obstruction in rats.

PubMed

Tokita, Y; Satoh, K; Sakaguchi, M; Endoh, Y; Mori, I; Yuzurihara, M; Sakakibara, I; Kase, Y; Takeda, S; Sasaki, H

2007-04-01

The present study investigated the effect of Daikenchuto (DKT) on postoperative intestinal adhesion in rats. We evaluated the effects of DKT, constituent medical herbs and active compounds on talc-induced intestinal adhesion in rats and DKT-induced contractions using isolated guinea pig ileum. DKT significantly prevented adhesion formation, and this action was inhibited by pretreatment with atropine or ruthenium red. The constituent medical herbs, Zanthoxylum Fruit and Maltose Syrup Powder significantly prevented adhesion formation. Moreover, hydroxy sanshool (HS) prevented adhesion formation, and this action was inhibited by pretreatment with ruthenium red. In contrast, DKT-induced contractions were inhibited by tetrodotoxin, atropine, and capsazepine. These results suggested that DKT had a preventive action on postoperative adhesive intestinal obstruction, and that this action was mediated by sensory and cholinergic nerves. Furthermore, HS was found to be one of the active compound of DKT, and its action was mediated by sensory nerves.

Reducing Ice Adhesion on Nonsmooth Metallic Surfaces: Wettability and Topography Effects.

PubMed

Ling, Edwin Jee Yang; Uong, Victor; Renault-Crispo, Jean-Sébastien; Kietzig, Anne-Marie; Servio, Phillip

2016-04-06

The effects of ice formation and accretion on external surfaces range from being mildly annoying to potentially life-threatening. Ice-shedding materials, which lower the adhesion strength of ice to its surface, have recently received renewed research attention as a means to circumvent the problem of icing. In this work, we investigate how surface wettability and surface topography influence the ice adhesion strength on three different surfaces: (i) superhydrophobic laser-inscribed square pillars on copper, (ii) stainless steel 316 Dutch-weave meshes, and (iii) multiwalled carbon nanotube-covered steel meshes. The finest stainless steel mesh displayed the best performance with a 93% decrease in ice adhesion relative to polished stainless steel, while the superhydrophobic square pillars exhibited an increase in ice adhesion by up to 67% relative to polished copper. Comparisons of dynamic contact angles revealed little correlation between surface wettability and ice adhesion. On the other hand, by considering the ice formation process and the fracture mechanics at the ice-substrate interface, we found that two competing mechanisms governing ice adhesion strength arise on nonplanar surfaces: (i) mechanical interlocking of the ice within the surface features that enhances adhesion, and (ii) formation of microcracks that act as interfacial stress concentrators, which reduce adhesion. Our analysis provides insight toward new approaches for the design of ice-releasing materials through the use of surface topographies that promote interfacial crack propagation.

Clinicopathological profile and surgical treatment of abdominal tuberculosis: a single centre experience in northwestern Tanzania

PubMed Central

2013-01-01

Background Abdominal tuberculosis continues to be a major public health problem worldwide and poses diagnostic and therapeutic challenges to general surgeons practicing in resource-limited countries. This study was conducted to describe the clinicopathological profile and outcome of surgical treatment of abdominal tuberculosis in our setting and compare with what is described in literature. Methods A prospective descriptive study of patients who presented with abdominal tuberculosis was conducted at Bugando Medical Centre (BMC) in northwestern Tanzania from January 2006 to February 2012. Ethical approval to conduct the study was obtained from relevant authorities. Statistical data analysis was performed using SPSS version 17.0. Results Out of 256 patients enrolled in the study, males outnumbered females. The median age was 28 years (range = 16–68 years). The majority of patients (77.3%) had primary abdominal tuberculosis. A total of 127 (49.6%) patients presented with intestinal obstruction, 106 (41.4%) with peritonitis, 17 (6.6%) with abdominal masses and 6 (2.3%) patients with multiple fistulae in ano. Forty-eight (18.8%) patients were HIV positive. A total of 212 (82.8%) patients underwent surgical treatment for abdominal tuberculosis. Bands /adhesions (58.5%) were the most common operative findings. Ileo-caecal region was the most common bowel involved in 122 (57.5%) patients. Release of adhesions and bands was the most frequent surgical procedure performed in 58.5% of cases. Complication and mortality rates were 29.7% and 18.8% respectively. The overall median length of hospital stay was 32 days and was significantly longer in patients with complications (p < 0.001). Advanced age (age ≥ 65 years), co-morbid illness, late presentation, HIV positivity and CD4+ count < 200 cells/μl were statistically significantly associated with mortality (p < 0.0001). The follow up of patients were generally poor as only 37.5% of patients were available for follow up at

Design of Xylose-Based Semisynthetic Polyurethane Tissue Adhesives with Enhanced Bioactivity Properties.

PubMed

Balcioglu, Sevgi; Parlakpinar, Hakan; Vardi, Nigar; Denkbas, Emir Baki; Karaaslan, Merve Goksin; Gulgen, Selam; Taslidere, Elif; Koytepe, Suleyman; Ates, Burhan

2016-02-01

Developing biocompatible tissue adhesives with high adhesion properties is a highly desired goal of the tissue engineering due to adverse effects of the sutures. Therefore, our work involves synthesis, characterization, adhesion properties, protein adsorption, in vitro biodegradation, in vitro and in vivo biocompatibility properties of xylose-based semisynthetic polyurethane (NPU-PEG-X) bioadhesives. Xylose-based semisynthetic polyurethanes were developed by the reaction among 4,4'-methylenebis(cyclohexyl isocyanate) (MCI), xylose and polyethylene glycol 200 (PEG). Synthesized polyurethanes (PUs) showed good thermal stability and high adhesion strength. The highest values in adhesion strength were measured as 415.0 ± 48.8 and 94.0 ± 2.8 kPa for aluminum substrate and muscle tissue in 15% xylose containing PUs (NPU-PEG-X-15%), respectively. The biodegradation of NPU-PEG-X-15% was also determined as 19.96 ± 1.04% after 8 weeks of incubation. Relative cell viability of xylose containing PU was above 86%. Moreover, 10% xylose containing NPU-PEG-X (NPU-PEG-X-10%) sample has favorable tissue response, and inflammatory reaction between 1 and 6 weeks implantation period. With high adhesiveness and biocompatibility properties, NPU-PEG-X can be used in the medical field as supporting materials for preventing the fluid leakage after abdominal surgery or wound closure.

Abdominal Pain

MedlinePlus

... and Recurrent or Functional Abdominal Pain (RAP or FAP) What is abdominal pain? Abdominal pain , or stomachache, ... recurrent abdominal pain (RAP) or functional abdominal pain (FAP)? If your health care provider has ruled out ...

Zones of Adhesion of the Abdomen: Implications for Abdominoplasty.

PubMed

Taylor, D Alastair

2017-02-01

The elucidation of the superficial fascial system (SFS) by Lockwood in 1991 has been the cornerstone of our understanding of abdominal excisional dynamics for the last 25 years. The SFS can be used for closure and, appropriately mobilized, for tension transmission in abdominoplasty, and lower body lifts. The pattern of SFS adhesion to muscle fascia and the zones of adhesion was also described but there are inconsistencies between the description and clinical experience. This study was performed to better describe the pattern of subcutaneous tissue adhesion to the trunk. Twenty pre-abdominoplasty patients were studied. A series of points were marked around the trunk and the skin moved in four opposing directions. The excursions were measured and the median plotted on a diagram. Two fresh cadavers were also dissected, removing all subcutaneous tissue circumferentially from the trunk muscle fascia and marking the strength of the adhesion with a colored pin. Three grades of adhesion were mapped. In the current study, maximal laxity was shown in the mid-lower abdomen and the anterior and lateral chest. Laxity was limited in the anterior and posterior midlines, over the lower back, and the lateral upper thigh. The cadaver dissection mapped adhesion which correlated with the skin laxity diagram. The detailed skin adhesion map better explains features of surface anatomy. Incorporating this understanding a tension vector of abdominoplasty closure obliquely inwards is proposed to maximally harvest the laxity of the anterior and lateral chest and to create further lowering and narrowing of the waist. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Extracellular proteases from Streptomyces phaeopurpureus ExPro138 inhibit spore adhesion, germination and appressorium formation in Colletotrichum coccodes.

PubMed

Palaniyandi, S A; Yang, S H; Suh, J-W

2013-07-01

To study the antifungal mechanism of proteases from Streptomyces phaeopurpureus strain ExPro138 towards Colletotrichum coccodes and to evaluate its utilization as biofungicide. We screened proteolytic Streptomyces strains from the yam rhizosphere with antifungal activity. Forty proteolytic Streptomyces were isolated, among which eleven isolates showed gelatinolytic activity and antagonistic activity on C. coccodes. Of the 11 isolates, protease preparation from an isolate designated ExPro138 showed antifungal activity. 16S rDNA sequence analysis of the strain showed 99% similarity with Streptomyces phaeopurepureus (EU841588.1). Zymography analysis of the ExPro138 culture filtrate revealed that the strain produced several extracellular proteases. The protease preparation inhibited spore germination, spore adhesion to polystyrene surface and appressorium formation. Microscopic study of the interaction between ExPro138 and C. coccodes revealed that ExPro138 was mycoparasitic on C. coccodes. The protease preparation also reduced anthracnose incidence on tomato fruits compared with untreated control. This study demonstrates possibility of utilizing antifungal proteases derived from antagonistic microbes as biofungicide. Microbial proteases having the ability to inhibit spore adhesion and appressorium formation could be used to suppress infection establishment by foliar fungal pathogens at the initial stages of the infection process. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

PLATELET ADHESION TO POLYURETHANE UREA UNDER PULSATILE FLOW CONDITIONS

PubMed Central

Navitsky, Michael A.; Taylor, Joshua O.; Smith, Alexander B.; Slattery, Margaret J.; Deutsch, Steven; Siedlecki, Christopher A.; Manning, Keefe B.

2014-01-01

Platelet adhesion to a polyurethane urea surface is a precursor to thrombus formation within blood-contacting cardiovascular devices, and platelets have been found to adhere strongly to polyurethane surfaces below a shear rate of approximately 500 s−1. The aim of the current work is to determine platelet adhesion properties to the polyurethane urea surface as a function of time varying shear exposure. A rotating disk system is used to study the influence of steady and pulsatile flow conditions (e.g. cardiac inflow and sawtooth waveforms) for platelet adhesion to the biomaterial surface. All experiments retain the same root mean square angular rotation velocity (29.63 rad/s) and waveform period. The disk is rotated in platelet rich bovine plasma for two hours with adhesion quantified by confocal microscopy measurements of immunofluorescently labeled bovine platelets. Platelet adhesion under pulsating flow is found to exponentially decay with increasing shear rate. Adhesion levels are found to depend upon peak platelet flux and shear rate regardless of rotational waveform. In combination with flow measurements, these results may be useful for predicting regions susceptible to thrombus formation within ventricular assist devices. PMID:24721222

Changes in E-cadherin rigidity sensing regulate cell adhesion.

PubMed

Collins, Caitlin; Denisin, Aleksandra K; Pruitt, Beth L; Nelson, W James

2017-07-18

Mechanical cues are sensed and transduced by cell adhesion complexes to regulate diverse cell behaviors. Extracellular matrix (ECM) rigidity sensing by integrin adhesions has been well studied, but rigidity sensing by cadherins during cell adhesion is largely unexplored. Using mechanically tunable polyacrylamide (PA) gels functionalized with the extracellular domain of E-cadherin (Ecad-Fc), we showed that E-cadherin-dependent epithelial cell adhesion was sensitive to changes in PA gel elastic modulus that produced striking differences in cell morphology, actin organization, and membrane dynamics. Traction force microscopy (TFM) revealed that cells produced the greatest tractions at the cell periphery, where distinct types of actin-based membrane protrusions formed. Cells responded to substrate rigidity by reorganizing the distribution and size of high-traction-stress regions at the cell periphery. Differences in adhesion and protrusion dynamics were mediated by balancing the activities of specific signaling molecules. Cell adhesion to a 30-kPa Ecad-Fc PA gel required Cdc42- and formin-dependent filopodia formation, whereas adhesion to a 60-kPa Ecad-Fc PA gel induced Arp2/3-dependent lamellipodial protrusions. A quantitative 3D cell-cell adhesion assay and live cell imaging of cell-cell contact formation revealed that inhibition of Cdc42, formin, and Arp2/3 activities blocked the initiation, but not the maintenance of established cell-cell adhesions. These results indicate that the same signaling molecules activated by E-cadherin rigidity sensing on PA gels contribute to actin organization and membrane dynamics during cell-cell adhesion. We hypothesize that a transition in the stiffness of E-cadherin homotypic interactions regulates actin and membrane dynamics during initial stages of cell-cell adhesion.

Changes in E-cadherin rigidity sensing regulate cell adhesion

PubMed Central

Collins, Caitlin; Pruitt, Beth L.; Nelson, W. James

2017-01-01

Mechanical cues are sensed and transduced by cell adhesion complexes to regulate diverse cell behaviors. Extracellular matrix (ECM) rigidity sensing by integrin adhesions has been well studied, but rigidity sensing by cadherins during cell adhesion is largely unexplored. Using mechanically tunable polyacrylamide (PA) gels functionalized with the extracellular domain of E-cadherin (Ecad-Fc), we showed that E-cadherin–dependent epithelial cell adhesion was sensitive to changes in PA gel elastic modulus that produced striking differences in cell morphology, actin organization, and membrane dynamics. Traction force microscopy (TFM) revealed that cells produced the greatest tractions at the cell periphery, where distinct types of actin-based membrane protrusions formed. Cells responded to substrate rigidity by reorganizing the distribution and size of high-traction-stress regions at the cell periphery. Differences in adhesion and protrusion dynamics were mediated by balancing the activities of specific signaling molecules. Cell adhesion to a 30-kPa Ecad-Fc PA gel required Cdc42- and formin-dependent filopodia formation, whereas adhesion to a 60-kPa Ecad-Fc PA gel induced Arp2/3-dependent lamellipodial protrusions. A quantitative 3D cell–cell adhesion assay and live cell imaging of cell–cell contact formation revealed that inhibition of Cdc42, formin, and Arp2/3 activities blocked the initiation, but not the maintenance of established cell–cell adhesions. These results indicate that the same signaling molecules activated by E-cadherin rigidity sensing on PA gels contribute to actin organization and membrane dynamics during cell–cell adhesion. We hypothesize that a transition in the stiffness of E-cadherin homotypic interactions regulates actin and membrane dynamics during initial stages of cell–cell adhesion. PMID:28674019

A Negative Regulator of Cellulose Biosynthesis, bcsR, Affects Biofilm Formation, and Adhesion/Invasion Ability of Cronobacter sakazakii.

PubMed

Gao, Jian-Xin; Li, Ping; Du, Xin-Jun; Han, Zhong-Hui; Xue, Rui; Liang, Bin; Wang, Shuo

2017-01-01

Cronobacter sakazakii is an important foodborne pathogen that causes neonatal meningitis and sepsis, with high mortality in neonates. However, very little information is available regarding the pathogenesis of C. sakazakii at the genetic level. In our previous study, a cellulose biosynthesis-related gene ( bcsR ) was shown to be involved in C. sakazakii adhesion/invasion into epithelial cells. In this study, the detailed functions of this gene were investigated using a gene knockout technique. A bcsR knockout mutant (Δ bcsR ) of C. sakazakii ATCC BAA-894 showed decreased adhesion/invasion (3.9-fold) in human epithelial cell line HCT-8. Biofilm formation by the mutant was reduced to 50% of that exhibited by the wild-type (WT) strain. Raman spectrometry was used to detect variations in biofilm components caused by bcsR knockout, and certain components, including carotenoids, fatty acids, and amides, were significantly reduced. However, another biofilm component, cellulose, was increased in Δ bcsR , suggesting that bcsR negatively affects cellulose biosynthesis. This result was also verified via RT-PCR, which demonstrated up-regulation of five crucial cellulose synthesis genes ( bcsA, B, C, E, Q ) in Δ bcsR . Furthermore, the expression of other virulence or biofilm-related genes, including flagellar assembly genes ( fliA, C, D ) and toxicity-related genes ( ompA, ompX, hfq ), was studied. The expression of fliC and ompA in the Δ bcsR mutant was found to be remarkably reduced compared with that in the wild-type and the others were also affected excepted ompX . In summary, bcsR is a negative regulator of cellulose biosynthesis but positively regulates biofilm formation and the adhesion/invasion ability of C. sakazakii .

Chronic Intussusception Caused by Diffuse Large B-Cell Lymphoma in a 6-Year-Old Girl Presenting with Abdominal Pain and Constipation for 2 Months.

PubMed

Choi, Sun-Hee; Han, Sang-Ah; Won, Kyu Yeoun

2016-02-01

The classical triad of abdominal pain, vomiting, and bloody stool is absent in chronic intussusception for more than 2 weeks. Here, we report a 6-year-old female with recurrent abdominal pain for 2 months. Ultrasonography of the abdomen revealed an ileocolic-type intussusception. The lesion accompanying the tight fibrous adhesion was treated by resection and ileocolic anastomosis. It was diagnosed as intussusception with diffuse large B-cell lymphoma. A high index of suspicion for abdominal pain in children should result in the correct diagnosis and appropriate management.

The sticky business of adhesion prevention in minimally invasive gynecologic surgery.

PubMed

Han, Esther S; Scheib, Stacey A; Patzkowsky, Kristin E; Simpson, Khara; Wang, Karen C

2017-08-01

The negative impact of postoperative adhesions has long been recognized, but available options for prevention remain limited. Minimally invasive surgery is associated with decreased adhesion formation due to meticulous dissection with gentile tissue handling, improved hemostasis, and limiting exposure to reactive foreign material; however, there is conflicting evidence on the clinical significance of adhesion-related disease when compared to open surgery. Laparoscopic surgery does not guarantee the prevention of adhesions because longer operative times and high insufflation pressure can promote adhesion formation. Adhesion barriers have been available since the 1980s, but uptake among surgeons remains low and there is no clear evidence that they reduce clinically significant outcomes such as chronic pain or infertility. In this article, we review the ongoing magnitude of adhesion-related complications in gynecologic surgery, currently available interventions and new research toward more effective adhesion prevention. Recent literature provides updated epidemiologic data and estimates of healthcare costs associated with adhesion-related complications. There have been important advances in our understanding of normal peritoneal healing and the pathophysiology of adhesions. Adhesion barriers continue to be tested for safety and effectiveness and new agents have shown promise in clinical studies. Finally, there are many experimental studies of new materials and pharmacologic and biologic prevention agents. There is great interest in new adhesion prevention technologies, but new agents are unlikely to be available for clinical use for many years. High-quality effectiveness and outcomes-related research is still needed.

E-Selectin Mediates Stem Cell Adhesion and Formation of Blood Vessels in a Murine Model of Infantile Hemangioma

PubMed Central

Smadja, David M.; Mulliken, John B.; Bischoff, Joyce

2013-01-01

Hemangioma stem cells (HemSCs) are multipotent cells isolated from infantile hemangioma (IH), which form hemangioma-like lesions when injected subcutaneously into immune-deficient mice. In this murine model, HemSCs are the primary target of corticosteroid, a mainstay therapy for problematic IH. The relationship between HemSCs and endothelial cells that reside in IH is not clearly understood. Adhesive interactions might be critical for the preferential accumulation of HemSCs and/or endothelial cells in the tumor. Therefore, we studied the interactions between HemSCs and endothelial cells (HemECs) isolated from IH surgical specimens. We found that HemECs isolated from proliferating phase IH, but not involuting phase, constitutively express E-selectin, a cell adhesion molecule not present in quiescent endothelial cells. E-selectin was further increased when HemECs were exposed to vascular endothelial growth factor–A or tumor necrosis factor–α. In vitro, HemSC migration and adhesion was enhanced by recombinant E-selectin but not P-selectin; both processes were neutralized by E-selectin–blocking antibodies. E-selectin–positive HemECs also stimulated migration and adhesion of HemSCs. In vivo, neutralizing antibodies to E-selectin strongly inhibited formation of blood vessels when HemSCs and HemECs were co-implanted in Matrigel. These data suggest that endothelial E-selectin could be a major ligand for HemSCs and thereby promote cellular interactions and vasculogenesis in IH. We propose that constitutively expressed E-selectin on endothelial cells in the proliferating phase is one mediator of the stem cell tropism in IH. PMID:23041613

Self-assembled Nano-layering at the Adhesive interface.

PubMed

Yoshida, Y; Yoshihara, K; Nagaoka, N; Hayakawa, S; Torii, Y; Ogawa, T; Osaka, A; Meerbeek, B Van

2012-04-01

According to the 'Adhesion-Decalcification' concept, specific functional monomers within dental adhesives can ionically interact with hydroxyapatite (HAp). Such ionic bonding has been demonstrated for 10-methacryloyloxydecyl dihydrogen phosphate (MDP) to manifest in the form of self-assembled 'nano-layering'. However, it remained to be explored if such nano-layering also occurs on tooth tissue when commercial MDP-containing adhesives (Clearfil SE Bond, Kuraray; Scotchbond Universal, 3M ESPE) were applied following common clinical application protocols. We therefore characterized adhesive-dentin interfaces chemically, using x-ray diffraction (XRD) and energy-dispersive x-ray spectroscopy (EDS), and ultrastructurally, using (scanning) transmission electron microscopy (TEM/STEM). Both adhesives revealed nano-layering at the adhesive interface, not only within the hybrid layer but also, particularly for Clearfil SE Bond (Kuraray), extending into the adhesive layer. Since such self-assembled nano-layering of two 10-MDP molecules, joined by stable MDP-Ca salt formation, must make the adhesive interface more resistant to biodegradation, it may well explain the documented favorable clinical longevity of bonds produced by 10-MDP-based adhesives.

Abdominal tap

MedlinePlus

Peritoneal tap; Paracentesis; Ascites - abdominal tap; Cirrhosis - abdominal tap; Malignant ascites - abdominal tap ... abdominal cavity ( most often cancer of the ovaries ) Cirrhosis of the liver Damaged bowel Heart disease Infection ...

Staged abdominal re-operation for abdominal trauma.

PubMed

Taviloglu, Korhan

2003-07-01

To review the current developments in staged abdominal re-operation for abdominal trauma. To overview the steps of damage control laparotomy. The ever increasing importance of the resuscitation phase with current intensive care unit (ICU) support techniques should be emphasized. General surgeons should be familiar to staged abdominal re-operation for abdominal trauma and collaborate with ICU teams, interventional radiologists and several other specialties to overcome this entity.

Oral water soluble contrast for the management of adhesive small bowel obstruction.

PubMed

Abbas, S; Bissett, I P; Parry, B R

2005-01-25

Adhesions are the leading cause of small bowel obstruction. Most adhesive small bowel obstructions resolve following conservative treatment but there is no consensus as to when conservative treatment should be considered unsuccessful and the patient should undergo surgery. Studies have shown that failure of an oral water-soluble contrast to reach the colon after a designated time indicates complete intestinal obstruction that is unlikely to resolve with conservative treatment. Other studies have suggested that the administration of water-soluble contrast is therapeutic in resolving the obstruction. The aims of this review are:1. To determine the reliability of water-soluble contrast media and serial abdominal radiographs in predicting the success of conservative treatment in patients admitted with adhesive small bowel obstruction.2. To determine the efficacy and safety of water-soluble contrast media in reducing the need for surgical intervention and reducing hospital stay in adhesive small bowel obstruction. The search was conducted using MeSH terms: ''Intestinal obstruction'', ''water-soluble contrast'', "Adhesions" and "Gastrografin", and combined with the Cochrane Collaboration highly sensitive search strategy for identifying randomised controlled trials and controlled clinical trials. 1. Prospective studies (to evaluate the diagnostic potential of water-soluble contrast in adhesive small bowel obstruction);2. Randomised clinical trials (to evaluate the therapeutic role). 1. Studies addressing the diagnostic role of water-soluble contrast were critically appraised and data presented as sensitivities, specificities and positive and negative likelihood ratios. Results were pooled and summary receiver operating characteristic (ROC) curve was constructed. 2. A meta-analysis of the data from therapeutic studies was performed using the Mantel -Haenszel test using both the fixed effect and random effects model. The appearance of water-soluble contrast in the caecum on

Proteinaceous determinants of surface colonization in bacteria: bacterial adhesion and biofilm formation from a protein secretion perspective

PubMed Central

Chagnot, Caroline; Zorgani, Mohamed A.; Astruc, Thierry; Desvaux, Mickaël

2013-01-01

Bacterial colonization of biotic or abiotic surfaces results from two quite distinct physiological processes, namely bacterial adhesion and biofilm formation. Broadly speaking, a biofilm is defined as the sessile development of microbial cells. Biofilm formation arises following bacterial adhesion but not all single bacterial cells adhering reversibly or irreversibly engage inexorably into a sessile mode of growth. Among molecular determinants promoting bacterial colonization, surface proteins are the most functionally diverse active components. To be present on the bacterial cell surface, though, a protein must be secreted in the first place. Considering the close association of secreted proteins with their cognate secretion systems, the secretome (which refers both to the secretion systems and their protein substrates) is a key concept to apprehend the protein secretion and related physiological functions. The protein secretion systems are here considered in light of the differences in the cell-envelope architecture between diderm-LPS (archetypal Gram-negative), monoderm (archetypal Gram-positive) and diderm-mycolate (archetypal acid-fast) bacteria. Besides, their cognate secreted proteins engaged in the bacterial colonization process are regarded from single protein to supramolecular protein structure as well as the non-classical protein secretion. This state-of-the-art on the complement of the secretome (the secretion systems and their cognate effectors) involved in the surface colonization process in diderm-LPS and monoderm bacteria paves the way for future research directions in the field. PMID:24133488

Overexpression of Catalase in Vascular Smooth Muscle Cells Prevents the Formation of Abdominal Aortic Aneurysms

PubMed Central

Parastatidis, Ioannis; Weiss, Daiana; Joseph, Giji; Taylor, W Robert

2013-01-01

Objective Elevated levels of oxidative stress have been reported in abdominal aortic aneurysms (AAA), but which reactive oxygen species (ROS) promotes the development of AAA remains unclear. Here we investigate the effect of the hydrogen peroxide (H2O2) degrading enzyme catalase on the formation of AAA. Approach and Results AAA were induced with the application of calcium chloride (CaCl2) on mouse infrarenal aortas. The administration of PEG-catalase, but not saline, attenuated the loss of tunica media and protected against AAA formation (0.91±0.1 mm vs. 0.76±0.09 mm). Similarly, in a transgenic mouse model, catalase over-expression in the vascular smooth muscle cells (VSMC) preserved the thickness of tunica media and inhibited aortic dilatation by 50% (0.85±0.14 mm vs. 0.57±0.08 mm). Further studies showed that injury with CaCl2 decreased catalase expression and activity in the aortic wall. Pharmacologic administration or genetic over-expression of catalase restored catalase activity and subsequently decreased matrix metalloproteinase activity. In addition, a profound reduction in inflammatory markers and VSMC apoptosis was evident in aortas of catalase over-expressing mice. Interestingly, as opposed to infusion of PEG-catalase, chronic over-expression of catalase in VSMC did not alter the total aortic H2O2 levels. Conclusions The data suggest that a reduction in aortic wall catalase activity can predispose to AAA formation. Restoration of catalase activity in the vascular wall enhances aortic VSMC survival and prevents AAA formation primarily through modulation of matrix metalloproteinase activity. PMID:23950141

Rac-WAVE-mediated actin reorganization is required for organization and maintenance of cell-cell adhesion.

PubMed

Yamazaki, Daisuke; Oikawa, Tsukasa; Takenawa, Tadaomi

2007-01-01

During cadherin-dependent cell-cell adhesion, the actin cytoskeleton undergoes dynamic reorganization in epithelial cells. Rho-family small GTPases, which regulate actin dynamics, play pivotal roles in cadherin-dependent cell-cell adhesion; however, the precise molecular mechanisms that underlie cell-cell adhesion formation remain unclear. Here we show that Wiskott-Aldrich syndrome protein family verprolin-homologous protein (WAVE)-mediated reorganization of actin, downstream of Rac plays an important role in normal development of cadherin-dependent cell-cell adhesions in MDCK cells. Rac-induced development of cadherin-dependent adhesions required WAVE2-dependent actin reorganization. The process of cell-cell adhesion is divided into three steps: formation of new cell-cell contacts, stabilization of these new contacts and junction maturation. WAVE1 and WAVE2 were expressed in MDCK cells. The functions of WAVE1 and WAVE2 were redundant in this system but WAVE2 appeared to play a more significant role. During the first step, WAVE2-dependent lamellipodial protrusions facilitated formation of cell-cell contacts. During the second step, WAVE2 recruited actin filaments to new cell-cell contacts and stabilized newly formed cadherin clusters. During the third step, WAVE2-dependent actin reorganization was required for organization and maintenance of mature cell-cell adhesions. Thus, Rac-WAVE-dependent actin reorganization is not only involved in formation of cell-cell adhesions but is also required for their maintenance.

Complex coacervates as a foundation for synthetic underwater adhesives

PubMed Central

Stewart, Russell J.; Wang, Ching Shuen; Shao, Hui

2011-01-01

Complex coacervation was proposed to play a role in the formation of the underwater bioadhesive of the Sandcastle worm (Phragmatopoma californica) based on the polyacidic and polybasic nature of the glue proteins and the balance of opposite charges at physiological pH. Morphological studies of the secretory system suggested the natural process does not involve complex coacervation as commonly defined. The distinction may not be important because electrostatic interactions likely play an important role in formation of the sandcastle glue. Complex coacervation has also been invoked in the formation of adhesive underwater silk fibers of caddisfly larvae and the adhesive plaques of mussels. A process similar to complex coacervation, that is, condensation and dehydration of biopolyelectrolytes through electrostatic associations, seems plausible for the caddisfly silk. This much is clear, the sandcastle glue complex coacervation model provided a valuable blueprint for the synthesis of a biomimetic, waterborne, underwater adhesive with demonstrated potential for repair of wet tissue. PMID:21081223

A rat hysteropexy model for evaluating adhesion formation and comparison of two different structured meshes.

PubMed

Gokmen-Karasu, Ayse Filiz; Aydin, Serdar; Sonmez, Fatma Cavide; Adanir, Ilknur; Ilhan, Gulsah; Ates, Seda

2017-11-01

Peritonization of mesh during sacrohysteropexy is generally advocated to prevent adhesions to the viscera; however, randomized clinical trials are lacking, and peritonization may not be completely possible in a laparoscopic hysteropexy procedure. Our main objective was to describe a basic experimental rat sacrohysteropexy model. We hypothesized that even when peritoneal closure was omitted, using composite mesh would result in less adhesions to the viscera. Twenty in-bred female virgin Wistar Hannover rats were used in this study. Standardized hysteropexy procedure and adhesion model is described step by step with two different mesh materials: polypropylene and a composite polyester. Mesh was anchored between the posterior cervix and anterior longitudinal ligament of the lumbar vertebrae. Macroscopic adhesion scores and histopathological tissue reaction was investigated. Macroscopically, the surface area involved in adhesions was similar between groups. However, adhesions in the polypropylene group were more dense, required sharp dissection for lysis, and yielded higher total macroscopic adhesion scores (p < 0.001). Histologically, a more pronounced host inflammatory response was encountered in the polyester group (p < 0.001). We describe a rat hysteropexy model and a previously established uterine adhesion model. Adhesion scores in the composite mesh group were lower, and bowel involvement was not seen. Our findings are promising, and further research investigating antiadhesive composite mesh use for hysterosacropexy would be appropriate, especially when peritoneal closure is omitted.

Changes in materials properties explain the effects of humidity on gecko adhesion.

PubMed

Puthoff, Jonathan B; Prowse, Michael S; Wilkinson, Matt; Autumn, Kellar

2010-11-01

Geckos owe their remarkable stickiness to millions of dry setae on their toes, and the mechanism of adhesion in gecko setae has been the topic of scientific scrutiny for over two centuries. Previously, we demonstrated that van der Waals forces are sufficient for strong adhesion and friction in gecko setae, and that water-based capillary adhesion is not required. However, recent studies demonstrated that adhesion increases with relative humidity (RH) and proposed that surface hydration and capillary water bridge formation is important or even necessary. In this study, we confirmed a significant effect of RH on gecko adhesion, but rejected the capillary adhesion hypothesis. While contact forces of isolated tokay gecko setal arrays increased with humidity, the increase was similar on hydrophobic and hydrophilic surfaces, inconsistent with a capillary mechanism. Contact forces increased with RH even at high shear rates, where capillary bridge formation is too slow to affect adhesion. How then can a humidity-related increase in adhesion and friction be explained? The effect of RH on the mechanical properties of setal β-keratin has escaped consideration until now. We discovered that an increase in RH softens setae and increases viscoelastic damping, which increases adhesion. Changes in setal materials properties, not capillary forces, fully explain humidity-enhanced adhesion, and van der Waals forces remain the only empirically supported mechanism of adhesion in geckos.

A non-canonical role for Rgnef in promoting integrin-stimulated focal adhesion kinase activation

PubMed Central

Miller, Nichol L. G.; Lawson, Christine; Kleinschmidt, Elizabeth G.; Tancioni, Isabelle; Uryu, Sean; Schlaepfer, David D.

2013-01-01

Summary Rgnef (also known as p190RhoGEF or ARHGEF28) is a Rho guanine-nucleotide-exchange factor (GEF) that binds focal adhesion kinase (FAK). FAK is recruited to adhesions and activated by integrin receptors binding to matrix proteins, such as fibronectin (FN). Canonical models place Rgnef downstream of integrin–FAK signaling in regulating Rho GTPase activity and cell movement. Herein, we establish a new, upstream role for Rgnef in enhancing FAK localization to early peripheral adhesions and promoting FAK activation upon FN binding. Rgnef-null mouse embryo fibroblasts (MEFs) exhibit defects in adhesion formation, levels of FAK phosphotyrosine (pY)-397 and FAK localization to peripheral adhesions upon re-plating on FN. Rgnef re-expression rescues these defects, but requires Rgnef–FAK binding. A mutation in the Rgnef pleckstrin homology (PH) domain inhibits adhesion formation, FAK localization, and FAK-Y397 and paxillin-Y118 phosphorylation without disrupting the Rgnef–FAK interaction. A GEF-inactive Rgnef mutant rescues FAK-Y397 phosphorylation and early adhesion localization, but not paxillin-Y118 phosphorylation. This suggests that, downstream of FN binding, paxillin-pY118 requires Rgnef GEF activity through a mechanism distinct from adhesion formation and FAK activation. These results support a scaffolding role for Rgnef in FAK localization and activation at early adhesions in a PH-domain-dependent but GEF-activity-independent manner. PMID:24006257

Anti-adhesive effects of a newly developed two-layered gelatin sheet in dogs.

PubMed

Torii, Hiroko; Takagi, Toshitaka; Urabe, Mamoru; Tsujimoto, Hiroyuki; Ozamoto, Yuki; Miyamoto, Hiroe; Ikada, Yoshihito; Hagiwara, Akeo

2017-08-01

Adhesion after pelvic surgery causes infertility, ectopic pregnancy, and ileus or abdominal pain. The materials currently available for clinical use are insufficient. The purpose of this study was to develop an anti-adhesive material that overcomes the limitations of conventional anti-adhesive agents. The adhesion prevention effects of three methods - a two-layered sheet composed of gelatin film and gelatin sponge, Seprafilm and INTERCEED - were evaluated in 37 dogs. Anti-adhesive effects were investigated macroscopically and microscopically in a cauterized uterus adhesion model. Cell growth on the materials in vitro using human peritoneal mesothelial cells, fibroblasts and uterine smooth muscle cells were also evaluated. The two-layered gelatin sheet had significantly superior anti-adhesive effects compared to the conventional materials (Seprafilm and INTERCEED). A single-cell layer of mature mesothelium formed three weeks after surgery in the gelatin group. Peritoneum regeneration in the Seprafilm and INTERCEED groups was delayed and incomplete in the early phase. Little inflammation around the materials occurred and cell growth was significantly proliferated with the gelatin sheet. The anti-adhesive effects of a two-layered gelatin sheet were superior to conventional agents in a cauterized canine uterus model, demonstrating early regeneration of the peritoneum, little inflammation and material endurance. The newly developed two-layered gelatin sheet is a useful option as an anti-adhesive agent for deeply injured and hemorrhagic sites. © 2017 The Authors. Journal of Obstetrics and Gynaecology Research published by John Wiley & Sons Australia, Ltd on behalf of Japan Society of Obstetrics and Gynecology.

E-selectin mediates stem cell adhesion and formation of blood vessels in a murine model of infantile hemangioma.

PubMed

Smadja, David M; Mulliken, John B; Bischoff, Joyce

2012-12-01

Hemangioma stem cells (HemSCs) are multipotent cells isolated from infantile hemangioma (IH), which form hemangioma-like lesions when injected subcutaneously into immune-deficient mice. In this murine model, HemSCs are the primary target of corticosteroid, a mainstay therapy for problematic IH. The relationship between HemSCs and endothelial cells that reside in IH is not clearly understood. Adhesive interactions might be critical for the preferential accumulation of HemSCs and/or endothelial cells in the tumor. Therefore, we studied the interactions between HemSCs and endothelial cells (HemECs) isolated from IH surgical specimens. We found that HemECs isolated from proliferating phase IH, but not involuting phase, constitutively express E-selectin, a cell adhesion molecule not present in quiescent endothelial cells. E-selectin was further increased when HemECs were exposed to vascular endothelial growth factor-A or tumor necrosis factor-α. In vitro, HemSC migration and adhesion was enhanced by recombinant E-selectin but not P-selectin; both processes were neutralized by E-selectin-blocking antibodies. E-selectin-positive HemECs also stimulated migration and adhesion of HemSCs. In vivo, neutralizing antibodies to E-selectin strongly inhibited formation of blood vessels when HemSCs and HemECs were co-implanted in Matrigel. These data suggest that endothelial E-selectin could be a major ligand for HemSCs and thereby promote cellular interactions and vasculogenesis in IH. We propose that constitutively expressed E-selectin on endothelial cells in the proliferating phase is one mediator of the stem cell tropism in IH. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Prevention of postoperative pericardial adhesions with TachoSil.

PubMed

Kuschel, Tarah J; Gruszka, Anna; Hermanns-Sachweh, Benita; Elyakoubi, Jaouad; Sachweh, Joerg S; Vázquez-Jiménez, Jaime F; Schnoering, Heike

2013-01-01

The prevention of the pericardial adhesions largely accountable for the technical difficulty and risk of injury inherent to resternotomy continues to gain in importance with the increasing frequency of reoperations. The hemostatic sponge TachoSil (Nycomed Austria GmbH, Linz, Austria), has shown promising results in adhesion prevention in several regions of the body. This study was designed to evaluate its effectiveness in the prevention of pericardial adhesions in comparison with the Gore-Tex (W. L. Gore and Assoc, Flagstaff, AZ) surgical membrane and a control. Twenty-four rabbits were distributed into 3 groups: TachoSil, Gore-Tex, or no barrier agent (control). After median sternotomy and pericardiotomy, the cardial surface was exposed to the aggravating effects of room air, irrigation, and gauze abrasion for one hour. A pericardial defect was created and repaired with one of the barrier agents, or left uncovered (control). Resternotomy was performed after 6 months for the evaluation of adhesion formation. Significantly fewer macroscopic adhesions were observed with TachoSil than Gore-Tex in all regions (p < 0.05) excluding the coronary arteries, where the difference in favor of TachoSil did not achieve significance (0.05< p-value <0.10). TachoSil also demonstrated significantly fewer retrosternal adhesions than the control, as well as a universal non-significant trend of fewer adhesions in all regions. The limited lesions present in the TachoSil group were filmy in nature and removed with blunt dissection relatively easily. No significant differences were found between Gore-Tex and the control. Microscopically, the least pronounced fibrosis formation and inflammatory reaction was detected with TachoSil. TachoSil is effective in the prevention of pericardial adhesions. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Elasto-capillarity in insect fibrillar adhesion.

PubMed

Gernay, Sophie; Federle, Walter; Lambert, Pierre; Gilet, Tristan

2016-08-01

The manipulation of microscopic objects is challenging because of high adhesion forces, which render macroscopic gripping strategies unsuitable. Adhesive footpads of climbing insects could reveal principles relevant for micro-grippers, as they are able to attach and detach rapidly during locomotion. However, the underlying mechanisms are still not fully understood. In this work, we characterize the geometry and contact formation of the adhesive setae of dock beetles (Gastrophysa viridula) by interference reflection microscopy. We compare our experimental results to the model of an elastic beam loaded with capillary forces. Fitting the model to experimental data yielded not only estimates for seta adhesion and compliance in agreement with previous direct measurements, but also previously unknown parameters such as the volume of the fluid meniscus and the bending stiffness of the tip. In addition to confirming the primary role of surface tension for insect adhesion, our investigation reveals marked differences in geometry and compliance between the three main kinds of seta tips in leaf beetles. © 2016 The Author(s).

A multi-targeted natural flavonoid myricetin impedes abnormal glioblastoma cell motility and invasiveness via suppressing lamellipodia and focal adhesions formation.

PubMed

Zhao, Hua-Fu; Wang, Gang; Wu, Chang-Peng; Zhou, Xiu-Ming; Wang, Jing; Chen, Zhong-Ping; To, Shing-Shun Tony; Li, Wei-Ping

2018-06-10

Glioblastoma multiforme (GBM) is the most aggressive and malignant primary brain tumor characterized by rapid growth and extensive infiltration to neighboring normal brain parenchyma, which contribute to tumor recurrence and poor prognosis. Myricetin is a natural flavonoid with potent anti-oxidant, anti-inflammatory and anti-cancer activities, which may serve as a potential and harmless agent for GBM treatment. To investigate the anti-glioblastoma effects of myricetin, GBM cells were treated with myricetin alone or in combination with temozolomide. Its effects on GBM cell motility and cytoskeletal structures including lamellipodia, focal adhesions and membrane ruffles were also evaluated. We showed that myricetin alone inhibited glioblastoma U-87 MG cell proliferation, migration and invasion, whereas combination of myricetin and temozolomide did not exhibit any synergistic effect. The inhibitory effect on GBM cell proliferation is independent of PTEN status. Moreover, myricetin showed less cytotoxicity to normal astrocytes than GBM cells. Formation of lamellipodia, focal adhesions, membrane ruffles and vasculogenic mimicry were blocked by myricetin though suppressing ROCK2, paxillin and cortactin phosphorylation. In addition, myricetin could bind to a series of kinases and scaffold proteins including PI3K catalytic isoforms (p110α, p110β and p110δ), PDK1, JNK, c-Jun, ROCK2, paxillin, vinculin and VE-cadherin, leading to inactivation of PI3K/Akt and JNK signaling. In conclusion, myricetin is a multi-targeted drug that has potent anti-migratory and anti-invasive effects on GBM cells via suppressing formation of lamellipodia and focal adhesions, suggesting that it may serve as an alternative option for GBM treatment. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Saliva-promoted adhesion of Streptococcus mutans MT8148 associates with dental plaque and caries experience.

PubMed

Shimotoyodome, A; Kobayashi, H; Tokimitsu, I; Hase, T; Inoue, T; Matsukubo, T; Takaesu, Y

2007-01-01

Colonization of enamel surfaces by Streptococcus mutans is thought to be initiated by the attachment of bacteria to a saliva-derived conditioning film (acquired pellicle). However, the clinical relevance of the contribution of saliva-promoted S. mutans adhesion in biofilm formation has not yet been fully elucidated. The aim of this study was to correlate saliva-promoted S. mutans adhesion with biofilm formation in humans. We correlated all measurements of salivary factors and dental plaque formation in 70 healthy subjects. Dental plaque development after thorough professional teeth cleaning correlated positively with S. mutans adhesion onto saliva-coated hydroxyapatite pellets and the glycoprotein content of either parotid or whole saliva. Saliva-promoted S. mutans adhesion and glycoprotein content were also positively correlated with each other in parotid and whole saliva. By contrast, neither salivary mutans streptococci, Lactobacillus nor Candida correlated with biofilm formation. Parotid saliva-mediated S. mutans adhesion was significantly higher in 12 caries-experienced (CE) subjects than in 9 caries-inexperienced (CI) subjects. Salivary S. mutans adhesion was significantly less (p < 0.01) in the CI group than in the CE group. In conclusion, the present findings suggest the initial S. mutans adhesion, modulated by salivary protein adsorption onto the enamel surface, as a possible correlate of susceptibility to dental plaque and caries. Copyright 2007 S. Karger AG, Basel.

CD44 in cancer progression: adhesion, migration and growth regulation.

PubMed

Marhaba, R; Zöller, M

2004-03-01

It is well established that the large array of functions that a tumour cell has to fulfil to settle as a metastasis in a distant organ requires cooperative activities between the tumour and the surrounding tissue and that several classes of molecules are involved, such as cell-cell and cell-matrix adhesion molecules and matrix degrading enzymes, to name only a few. Furthermore, metastasis formation requires concerted activities between tumour cells and surrounding cells as well as matrix elements and possibly concerted activities between individual molecules of the tumour cell itself. Adhesion molecules have originally been thought to be essential for the formation of multicellular organisms and to tether cells to the extracellular matrix or to neighbouring cells. CD44 transmembrane glycoproteins belong to the families of adhesion molecules and have originally been described to mediate lymphocyte homing to peripheral lymphoid tissues. It was soon recognized that the molecules, under selective conditions, may suffice to initiate metastatic spread of tumour cells. The question remained as to how a single adhesion molecule can fulfil that task. This review outlines that adhesion is by no means a passive task. Rather, ligand binding, as exemplified for CD44 and other similar adhesion molecules, initiates a cascade of events that can be started by adherence to the extracellular matrix. This leads to activation of the molecule itself, binding to additional ligands, such as growth factors and matrix degrading enzymes, complex formation with additional transmembrane molecules and association with cytoskeletal elements and signal transducing molecules. Thus, through the interplay of CD44 with its ligands and associating molecules CD44 modulates adhesiveness, motility, matrix degradation, proliferation and cell survival, features that together may well allow a tumour cell to proceed through all steps of the metastatic cascade.

Glycan-functionalized diamond nanoparticles as potent E. coli anti-adhesives.

PubMed

Barras, Alexandre; Martin, Fernando Ariel; Bande, Omprakash; Baumann, Jean-Sébastien; Ghigo, Jean-Marc; Boukherroub, Rabah; Beloin, Christophe; Siriwardena, Aloysius; Szunerits, Sabine

2013-03-21

Bacterial attachment and subsequent biofilm formation on biotic surfaces or medical devices is an increasing source of infections in clinical settings. A large proportion of these biofilm-related infections are caused by Escherichia coli, a major nosocomial pathogen, in which the major adhesion factor is the FimH adhesin located at the tip of type 1 fimbriae. Inhibition of FimH-mediated adhesion has been identified as an efficient antibiotic-alternative strategy to potentially reduce E. coli-related infections. In this article we demonstrate that nanodiamond particles, covently modified with mannose moieties by a "click" chemistry approach, are able to efficiently inhibit E. coli type 1 fimbriae-mediated adhesion to eukaryotic cells with relative inhibitory potency (RIP) of as high as 9259 (bladder cell adhesion assay), which is unprecedented when compared with RIP values previously reported for alternate multivalent mannose-functionalized nanostructures designed to inhibit E. coli adhesion. Also remarkable is that these novel mannose-modified NDs reduce E. coli biofilm formation, a property previously not observed for multivalent glyco-nanoparticles and rarely demonstrated for other multivalent or monovalent mannose glycans. This work sets the stage for the further evaluation of these novel NDs as an anti-adhesive therapeutic strategy against E. coli-derived infections.

Oral water soluble contrast for the management of adhesive small bowel obstruction.

PubMed

Abbas, S; Bissett, I P; Parry, B R

2007-07-18

Adhesions are the leading cause of small bowel obstruction. Gastrografin transit time may allow for the selection of appropriate patients for non-operative management. Some studies have shown when the contrast does not reach the colon after a designated time it indicates complete intestinal obstruction that is unlikely to resolve with conservative treatment. When the contrast does reach the large bowel, it indicates partial obstruction and patients are likely to respond to conservative treatment. Other studies have suggested that the administration of water-soluble contrast is therapeutic in resolving the obstruction. To determine the reliability of water-soluble contrast media and serial abdominal radiographs in predicting the success of conservative treatment in patients admitted with adhesive small bowel obstruction.Furthermore, to determine the efficacy and safety of water-soluble contrast media in reducing the need for surgical intervention and reducing hospital stay in adhesive small bowel obstruction. The search was conducted using MESH terms: ''Intestinal obstruction'', ''water-soluble contrast'', "Adhesions" and "Gastrografin". The later combined with the Cochrane Collaboration highly sensitive search strategy for identifying randomised controlled trials and controlled clinical trials. 1. Prospective studies were included to evaluate the diagnostic potential of water-soluble contrast in adhesive small bowel obstruction.2. Randomised clinical trials were selected to evaluate the therapeutic role. 1. Studies that addressed the diagnostic role of water-soluble contrast were critically appraised and data presented as sensitivities, specificities and positive and negative likelihood ratios. Results were pooled and summary ROC curve was constructed.2. A meta-analysis of the data from therapeutic studies was performed using the Mantel -Henszel test using both the fixed effect and random effect models. The appearance of water-soluble contrast in the colon on an

[Abdominal trauma].

PubMed

Sido, B; Grenacher, L; Friess, H; Büchler, M W

2005-09-01

Blunt abdominal trauma is much more frequent than penetrating abdominal trauma in Europe. As a consequence of improved quality of computed tomography, even complex liver injuries are increasingly being treated conservatively. However, missed hollow viscus injuries still remain a problem, as they considerably increase mortality in multiply injured patients. Laparoscopy decreases the rate of unnecessary laparotomies in perforating abdominal trauma and helps to diagnose injuries of solid organs and the diaphragm. However, the sensitivity in detecting hollow viscus injuries is low and the role of laparoscopy in blunt abdominal injury has not been defined. If intra-abdominal bleeding is difficult to control in hemodynamically unstable patients, damage control surgery with packing of the liver, total splenectomy, and provisional closure of hollow viscus injuries is of importance. Definitive surgical treatment follows hemodynamic stabilization and restoration of hemostasis. Injuries of the duodenum and pancreas after blunt abdominal trauma are often associated with other intra-abdominal injuries and the treatment depends on their location and severity.

A Relation Between Near-Wall Particle-Hemodynamics and Onset of Thrombus Formation in Abdominal Aortic Aneurysms

PubMed Central

Basciano, C.; Kleinstreuer, C.; Hyun, S.; Finol, E. A.

2014-01-01

A novel computational particle-hemodynamics analysis of key criteria for the onset of an intraluminal thrombus (ILT) in a patient-specific abdominal aortic aneurysm (AAA) is presented. The focus is on enhanced platelet and white blood cell residence times as well as their elevated surface-shear loads in near-wall regions of the AAA sac. The generalized results support the hypothesis that a patient's AAA geometry and associated particle-hemodynamics have the potential to entrap activated blood particles, which will play a role in the onset of ILT. Although the ILT history of only a single patient was considered, the modeling and simulation methodology provided allow for the development of an efficient computational tool to predict the onset of ILT formation in complex patient-specific cases. PMID:21373952

Chronic abdominal wall pain misdiagnosed as functional abdominal pain.

PubMed

van Assen, Tijmen; de Jager-Kievit, Jenneke W A J; Scheltinga, Marc R; Roumen, Rudi M H

2013-01-01

The abdominal wall is often neglected as a cause of chronic abdominal pain. The aim of this study was to identify chronic abdominal wall pain syndromes, such as anterior cutaneous nerve entrapment syndrome (ACNES), in a patient population diagnosed with functional abdominal pain, including irritable bowel syndrome, using a validated 18-item questionnaire as an identification tool. In this cross-sectional analysis, 4 Dutch primary care practices employing physicians who were unaware of the existence of ACNES were selected. A total of 535 patients ≥18 years old who were registered with a functional abdominal pain diagnosis were approached when they were symptomatic to complete the questionnaire (maximum 18 points). Responders who scored at least the 10-point cutoff value (sensitivity, 0.94; specificity, 0.92) underwent a diagnostic evaluation to establish their final diagnosis. The main outcome was the presence and prevalence of ACNES in a group of symptomatic patients diagnosed with functional abdominal pain. Of 535 patients, 304 (57%) responded; 167 subjects (31%) recently reporting symptoms completed the questionnaire. Of 23 patients who scored above the 10-point cutoff value, 18 were available for a diagnostic evaluation. In half of these subjects (n = 9) functional abdominal pain (including IBS) was confirmed. However, the other 9 patients were suffering from abdominal wall pain syndrome, 6 of whom were diagnosed with ACNES (3.6% prevalence rate of symptomatic subjects; 95% confidence interval, 1.7-7.6), whereas the remaining 3 harbored a painful lipoma, an abdominal herniation, and a painful scar. A clinically relevant portion of patients previously diagnosed with functional abdominal pain syndrome in a primary care environment suffers from an abdominal wall pain syndrome such as ACNES.

The risk of volvulus in abdominal wall defects.

PubMed

Abdelhafeez, Abdelhafeez H; Schultz, Jessica A; Ertl, Allison; Cassidy, Laura D; Wagner, Amy J

2015-04-01

Congenital abdominal wall defects are associated with abnormal intestinal rotation and fixation. A Ladd's procedure is not routinely performed in these patients; it is believed intestinal fixation is provided by adhesions that develop post-repair of the defects. However, patients with omphalocele may not have adequately protective postoperative adhesions because of difference in the inflammatory state of the bowel wall and in repair strategy. The aim of this study is to describe the occurrence of midgut volvulus in patients with gastroschisis or omphalocele. A retrospective chart review was performed for all patients managed in a single institution born between 1/1/2000 and 12/31/2008 with a diagnosis of gastroschisis or omphalocele. Patient charts were reviewed through 12/31/2012 for occurrence of midgut volvulus or need for second laparotomy. Of the 206 patients identified with abdominal wall defects, 142 patients (69%) had gastroschisis and 64 patients (31%) had omphalocele. Patients' follow up ranged from 4 years to 13 years. The median gestational age was 36 weeks (26-41 weeks) and the median birth weight was 2.42 kg (0.8-4.87 kg). None of the patients with gastroschisis developed midgut volvulus, however two patients (3%) with omphalocele developed midgut volvulus. No patients with gastroschisis developed midgut volvulus. Therefore, the current practice of not routinely performing a Ladd's procedure is a safe approach during surgical repair of gastroschisis. The two cases of volvulus in patients with omphalocele may be related to less bowel fixation. It is necessary to examine current practice in regards to the need for assessing the risk of volvulus during omphalocele closure and counseling of these patients. This assessment may be achieved via routine examination of the width of the small bowel mesenteric base, whenever feasible; however, the sample size is relatively small to draw any definitive conclusions. Published by Elsevier Inc.

Abdominal Adhesions

MedlinePlus

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Acute abdominal conditions in people with sickle cell disease: a 10-year experience in Port Harcourt, Nigeria.

PubMed

Jebbin, N J; Adotey, J M

2011-01-01

Abdominal crises (vaso-occlusive) are not infrequent in patients with sickle cell anemia. They usually present as acute abdomen. These patients none the less present with other causes of acute abdomen like others without hemoglobinopathy. Six cases of surgical acute abdomen in sickle cell disease patients treated in the University of Port Harcourt Teaching Hospital (UPTH) are presented. Six sickle cell anaemia patients presenting with acute abdominal conditions from 1999 to 2008 (inclusive) in the University of Port Harcourt Teaching Hospital were studied retrospectively (two patients) and prospectively (four patients). After initial resuscitation, appropriate surgical procedures, namely, appendicectomy (2), cholecystectomy (1), open drainage of splenic abscess (1), and release of adhesive band (1) were performed. Six cases were treated (female/male ratio 2:1). Four patients were in the 11-20 year age group. Two patients had appendicectomy and two presented with acute cholecystitis/cholelithiasis, one of whom had open cholecystectomy. One young girl had drainage of splenic abscess and a 42-year-old male had division of obstructive adhesive band at laparotomy. There were two complications, namely, postoperative haemorrhage (in cholecystectomy patient) and acute chest syndrome (in one appendicectomy patient). These were successfully managed with blood transfusion and antibiotic/oxygen therapy, respectively. There was no mortality. Sickle cell anaemia patients are not exempt from acute abdominal conditions requiring surgery. A high index of suspicion coupled with repeated clinical examination is needed for early diagnosis and appropriate treatment.

Altering wettability to recover more oil from tight formations

DOE PAGES

Brady, Patrick V.; Bryan, Charles R.; Thyne, Geoffrey; ...

2016-06-03

We describe here a method for chemically modifying fracturing fluids and overflushes to chemically increase oil recovery from tight formations. Oil wetting of tight formations is usually controlled by adhesion to illite, kerogen, or both; adhesion to carbonate minerals may also play a role. Oil-illite adhesion is sensitive to salinity, dissolved divalent cation content, and pH. We measure oil-rock adhesion with middle Bakken formation oil and core to verify a surface complexation model of reservoir wettability. The agreement between the model and experiments suggests that wettability trends in tight formations can be quantitatively predicted and that fracturing fluid and overflushmore » compositions can be individually tailored to increase oil recovery.« less

Altering wettability to recover more oil from tight formations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brady, Patrick V.; Bryan, Charles R.; Thyne, Geoffrey

We describe here a method for chemically modifying fracturing fluids and overflushes to chemically increase oil recovery from tight formations. Oil wetting of tight formations is usually controlled by adhesion to illite, kerogen, or both; adhesion to carbonate minerals may also play a role. Oil-illite adhesion is sensitive to salinity, dissolved divalent cation content, and pH. We measure oil-rock adhesion with middle Bakken formation oil and core to verify a surface complexation model of reservoir wettability. The agreement between the model and experiments suggests that wettability trends in tight formations can be quantitatively predicted and that fracturing fluid and overflushmore » compositions can be individually tailored to increase oil recovery.« less

Regulation of the epithelial adhesion molecule CEACAM1 is important for palate formation.

PubMed

Mima, Junko; Koshino, Aya; Oka, Kyoko; Uchida, Hitoshi; Hieda, Yohki; Nohara, Kanji; Kogo, Mikihiko; Chai, Yang; Sakai, Takayoshi

2013-01-01

Cleft palate results from a mixture of genetic and environmental factors and occurs when the bilateral palatal shelves fail to fuse. The objective of this study was to search for new genes involved in mouse palate formation. Gene expression of murine embryonic palatal tissue was analyzed at various developmental stages before, during, and after palate fusion using GeneChip® microarrays. Ceacam1 was one of the highly up-regulated genes during palate formation, and this was confirmed by quantitative real-time PCR. Immunohistochemical staining showed that CEACAM1 was present in prefusion palatal epithelium and was degraded during fusion. To investigate the developmental role of CEACAM1, function-blocking antibody was added to embryonic mouse palate in organ culture. Palatal fusion was inhibited by this function-blocking antibody. To investigate the subsequent developmental role of CEACAM1, we characterized Ceacam1-deficient (Ceacam1(-/-)) mice. Epithelial cells persisted abnormally at the midline of the embryonic palate even on day E16.0, and palatal fusion was delayed in Ceacam1(-/-) mice. TGFβ3 expression, apoptosis, and cell proliferation in palatal epithelium were not affected in the palate of Ceacam1(-/-)mice. However, CEACAM1 expression was retained in the remaining MEE of TGFβ-deficient mice. These results suggest that CEACAM1 has roles in the initiation of palatal fusion via epithelial cell adhesion.

The adhesive strength and initial viscosity of denture adhesives.

PubMed

Han, Jian-Min; Hong, Guang; Dilinuer, Maimaitishawuti; Lin, Hong; Zheng, Gang; Wang, Xin-Zhi; Sasaki, Keiichi

2014-11-01

To examine the initial viscosity and adhesive strength of modern denture adhesives in vitro. Three cream-type denture adhesives (Poligrip S, Corect Cream, Liodent Cream; PGS, CRC, LDC) and three powder-type denture adhesives (Poligrip Powder, New Faston, Zanfton; PGP, FSN, ZFN) were used in this study. The initial viscosity was measured using a controlled-stress rheometer. The adhesive strength was measured according to ISO-10873 recommended procedures. All data were analyzed independently by one-way analysis of variance combined with a Student-Newman-Keuls multiple comparison test at a 5% level of significance. The initial viscosity of all the cream-type denture adhesives was lower than the powder-type adhesives. Before immersion in water, all the powder-type adhesives exhibited higher adhesive strength than the cream-type adhesives. However, the adhesive strength of cream-type denture adhesives increased significantly and exceeded the powder-type denture adhesives after immersion in water. For powder-type adhesives, the adhesive strength significantly decreased after immersion in water for 60 min, while the adhesive strength of the cream-type adhesives significantly decreased after immersion in water for 180 min. Cream-type denture adhesives have lower initial viscosity and higher adhesive strength than powder type adhesives, which may offer better manipulation properties and greater efficacy during application.

Idiopathic sclerosing encapsulating peritonitis (or abdominal cocoon).

PubMed

Serafimidis, Costas; Katsarolis, Ioannis; Vernadakis, Spyros; Rallis, George; Giannopoulos, George; Legakis, Nikolaos; Peros, George

2006-02-13

Idiopathic sclerosing encapsulating peritonitis (or abdominal cocoon) is a rare cause of small bowel obstruction, especially in adult population. Diagnosis is usually incidental at laparotomy. We discuss one such rare case, outlining the fact that an intra-operative surprise diagnosis could have been facilitated by previous investigations. A 56 year-old man presented in A&E department with small bowel ileus. He had a history of 6 similar episodes of small bowel obstruction in the past 4 years, which resolved with conservative treatment. Pre-operative work-up did not reveal any specific etiology. At laparotomy, a fibrous capsule was revealed, in which small bowel loops were encased, with the presence of interloop adhesions. A diagnosis of abdominal cocoon was established and extensive adhesiolysis was performed. The patient had an uneventful recovery and follow-up. Idiopathic sclerosing encapsulating peritonitis, although rare, may be the cause of a common surgical emergency such as small bowel ileus, especially in cases with attacks of non-strangulating obstruction in the same individual. A high index of clinical suspicion may be generated by the recurrent character of small bowel ileus combined with relevant imaging findings and lack of other plausible etiologies. Clinicians must rigorously pursue a preoperative diagnosis, as it may prevent a "surprise" upon laparotomy and result in proper management.

Cell adhesion on nanotopography

NASA Astrophysics Data System (ADS)

Tsai, Irene; Kimura, Masahiro; Stockton, Rebecca; Jacobson, Bruce; Russell, Thomas

2003-03-01

Cell adhesion, a key element in understanding the cell-biomaterial interactions, underpins proper cell growth, function and survival. Understanding the parameters influencing cell adhesion is critical for applications in biosensors, implants and bioreactors. A gradient surface is used to study the effect of the surface topography on cell adhesion. A gradient surface is generated by block copolymer and homopolymer blends. The two homopolymers will phase separate on the micron scale and gradually decrease to nano-scale by the microphase separation of the diblock. Gradient surfaces offer a unique opportunity to probe lateral variations in the topography and interactions. Using thin films of mixtures of diblock copolymers of PS-b-MMA with PS and PMMA homopolymers, where the concentration of the PS-b-MMA varies across the surface, a gradient in the size scale of the morphology, from the nanoscopic to microscopic, was produced. By UV exposure, the variation in morphology translated into a variation in topography. The extent of cell spreading and cytoskeleton formation was investigated and marked dependence on the length scale of the surface topography was found.

Evaluating abdominal oedema during experimental sepsis using an isotope technique.

PubMed

Lattuada, Marco; Maripuu, Enn; Segerstad, Carl Hard af; Lundqvist, Hans; Hedenstierna, Göran

2012-05-01

Abdominal oedema is common in sepsis. A technique for the study of such oedema may guide in the fluid regime of these patients. We modified a double-isotope technique to evaluate abdominal organ oedema and fluid extravasation in 24 healthy or endotoxin-exposed ('septic') piglets. Two different markers were used: red blood cells (RBC) labelled with Technetium-99m ((99m)Tc) and Transferrin labelled with Indium111 ((111)In). Images were acquired on a dual-head gamma camera. Microscopic evaluation of tissue biopsies was performed to compare data with the isotope technique. No (99m)Tc activity was measured in the plasma fraction in blood sampled after labelling. Similarly, after molecular size gel chromatography, (111)In activity was exclusively found in the high molecular fraction of the plasma. Extravasation of transferrin, indicating the degree of abdominal oedema, was 4·06 times higher in the LPS group compared to the healthy controls (P<0·0001). Abdominal free fluid, studied in 3 animals, had as high (111)In activity as in plasma, but no (99m)Tc activity. Intestinal lymphatic vessel size was higher in LPS (3·7 ± 1·1 μm) compared to control animals (0·6 + 0·2 μm; P<0·001) and oedema correlated to villus diameter (R(2) = 0·918) and lymphatic diameter (R(2) = 0·758). A correlation between a normalized index of oedema formation (NI) and intra-abdominal pressure (IAP) was also found: NI = 0·46*IAP-3·3 (R(2) = 0·56). The technique enables almost continuous recording of abdominal oedema formation and may be a valuable tool in experimental research, with the potential to be applied in the clinic. © 2011 The Authors. Clinical Physiology and Functional Imaging © 2011 Scandinavian Society of Clinical Physiology and Nuclear Medicine.

Osteoblast adhesion to orthopaedic implant alloys: Effects of cell adhesion molecules and diamond-like carbon coating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kornu, R.; Kelly, M.A.; Smith, R.L.

1996-11-01

In total joint arthroplasty, long-term outcomes depend in part on the biocompatibility of implant alloys. This study analyzed effects of surface finish and diamond-like carbon coating on osteoblast cell adhesion to polished titanium-aluminum-vanadium and polished or grit-blasted cobalt-chromium-molybdenum alloys. Osteoblast binding was tested in the presence and absence of the cell adhesion proteins fibronectin, laminin, fibrinogen, and vitronectin and was quantified by measurement of DNA content. Although adherence occurred in serum-free medium, maximal osteoblast binding required serum and was similar for titanium and cobalt alloys at 2 and 12 hours. With the grit-blasted cobalt alloy, cell binding was reduced 48%more » (p < 0.05) by 24 hours. Coating the alloys with diamond-like carbon did not alter osteoblast adhesion, whereas fibronectin pretreatment increased cell binding 2.6-fold (p < 0.05). In contrast, fibrinogen, vitronectin, and laminin did not enhance cell adhesion. These results support the hypothesis that cell adhesion proteins can modify cell binding to orthopaedic alloys. Although osteoblast binding was not affected by the presence of diamond-like carbon, this coating substance may influence other longer term processes, such as bone formation, and deserves further study. 40 refs., 4 figs.« less

The antagonistic effect of Saccharomyces boulardii on Candida albicans filamentation, adhesion and biofilm formation.

PubMed

Krasowska, Anna; Murzyn, Anna; Dyjankiewicz, Agnieszka; Łukaszewicz, Marcin; Dziadkowiec, Dorota

2009-12-01

The dimorphic fungus Candida albicans is a member of the normal flora residing in the intestinal tract of humans. In spite of this, under certain conditions it can induce both superficial and serious systemic diseases, as well as be the cause of gastrointestinal infections. Saccharomyces boulardii is a yeast strain that has been shown to have applications in the prevention and treatment of intestinal infections caused by bacterial pathogens. The purpose of this study was to determine whether S. boulardii affects the virulence factors of C. albicans. We demonstrate the inhibitory effect of live S. boulardii cells on the filamentation (hyphae and pseudohyphae formation) of C. albicans SC5314 strain proportional to the amount of S. boulardii added. An extract from S. boulardii culture has a similar effect. Live S. boulardii and the extract from S. boulardii culture filtrate diminish C. albicans adhesion to and subsequent biofilm formation on polystyrene surfaces under both aerobic and microaerophilic conditions. This effect is very strong and requires lower doses of S. boulardii cells or concentrations of the extract than serum-induced filamentation tests. Saccharomyces boulardii has a strong negative effect on very important virulence factors of C. albicans, i.e. the ability to form filaments and to adhere and form biofilms on plastic surfaces.

Dietary fish oil supplementation inhibits formation of endometriosis-associated adhesions in a chimeric mouse model.

PubMed

Herington, Jennifer L; Glore, Dana R; Lucas, John A; Osteen, Kevin G; Bruner-Tran, Kaylon L

2013-02-01

To examine whether dietary fish oil supplementation reduces development of spontaneous endometriosis-associated adhesions using an established model. Laboratory-based study. Medical center research laboratory. PATIENT(S)/ANIMAL(S): Disease-free women of reproductive age and nude mice. Women were not provided any intervention. Mice were randomized to receive fish oil supplementation or control diet. Experimental endometriosis was established in mice via injection of human endometrial tissue within 16 hours of ovariectomy. Mice were provided standard or menhaden fish oil-supplemented diets for ≥ 2 weeks before initiation of experimental endometriosis and until killing them 1 week later. At necropsy, mice were examined for the presence and extent of adhesions and endometriotic-like lesions. Tissues were excised and morphologically characterized. Adhesions/lesions were reduced in mice provided with dietary fish oil compared with control animals. Leukocytes were more numerous within the adhesions/lesions of the mice maintained on the standard diet compared with animals provided with fish oil. As indicated by staining intensity, collagen deposition was greater at adhesion sites within control mice compared with fish oil-supplemented animals. Wound-healing associated with surgery created an inflammatory peritoneal microenvironment that promoted the development of both experimental endometriosis and adhesions in a murine model. Targeting excessive inflammation with fish oil may be an effective adjuvant therapy to reduce the development of postsurgical adhesions related to endometriosis. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Microbial Adhesion and Biofilm Formation on Microfiltration Membranes: A Detailed Characterization Using Model Organisms with Increasing Complexity

PubMed Central

Vanysacker, L.; Denis, C.; Declerck, P.; Piasecka, A.; Vankelecom, I. F. J.

2013-01-01

Since many years, membrane biofouling has been described as the Achilles heel of membrane fouling. In the present study, an ecological assay was performed using model systems with increasing complexity: a monospecies assay using Pseudomonas aeruginosa or Escherichia coli separately, a duospecies assay using both microorganisms, and a multispecies assay using activated sludge with or without spiked P. aeruginosa. The microbial adhesion and biofilm formation were evaluated in terms of bacterial cell densities, species richness, and bacterial community composition on polyvinyldifluoride, polyethylene, and polysulfone membranes. The data show that biofouling formation was strongly influenced by the kind of microorganism, the interactions between the organisms, and the changes in environmental conditions whereas the membrane effect was less important. The findings obtained in this study suggest that more knowledge in species composition and microbial interactions is needed in order to understand the complex biofouling process. This is the first report describing the microbial interactions with a membrane during the biofouling development. PMID:23986906

Modification of the surfaces of medical devices to prevent microbial adhesion and biofilm formation.

PubMed

Desrousseaux, C; Sautou, V; Descamps, S; Traoré, O

2013-10-01

The development of devices with surfaces that have an effect against microbial adhesion or viability is a promising approach to the prevention of device-related infections. To review the strategies used to design devices with surfaces able to limit microbial adhesion and/or growth. A PubMed search of the published literature. One strategy is to design medical devices with a biocidal agent. Biocides can be incorporated into the materials or coated or covalently bonded, resulting either in release of the biocide or in contact killing without release of the biocide. The use of biocides in medical devices is debated because of the risk of bacterial resistance and potential toxicity. Another strategy is to modify the chemical or physical surface properties of the materials to prevent microbial adhesion, a complex phenomenon that also depends directly on microbial biological structure and the environment. Anti-adhesive chemical surface modifications mostly target the hydrophobicity features of the materials. Topographical modifications are focused on roughness and nanostructures, whose size and spatial organization are controlled. The most effective physical parameters to reduce bacterial adhesion remain to be determined and could depend on shape and other bacterial characteristics. A prevention strategy based on reducing microbial attachment rather than on releasing a biocide is promising. Evidence of the clinical efficacy of these surface-modified devices is lacking. Additional studies are needed to determine which physical features have the greatest potential for reducing adhesion and to assess the usefulness of antimicrobial coatings other than antibiotics. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Management of intra-abdominal hypertension and abdominal compartment syndrome: a review

PubMed Central

2014-01-01

Patients in the intensive care unit (ICU) are at risk of developing of intra abdominal hypertension (IAH) and abdominal compartment syndrome (ACS). Aim: This review seeks to define IAH and ACS, identify the aetiology and presentation of IAH and ACS, identify IAP measurement techniques, identify current management and discuss the implications of IAH and ACS for nursing practice. A search of the electronic databases was supervised by a health librarian. The electronic data bases Cumulative Index of Nursing and Allied Health Literature (CINAHL); Medline, EMBASE, and the World Wide Web was undertaken from 1996- January 2011 using MeSH and key words which included but not limited to: abdominal compartment syndrome, intra -abdominal hypertension, intra-abdominal pressure in adult populations met the search criteria and were reviewed by three authors using a critical appraisal tool. Data derived from the retrieved material are discussed under the following themes: (1) etiology of intra-abdominal hypertension; (2) strategies for measuring intra-abdominal pressure (3) the manifestation of abdominal compartment syndrome; and (4) the importance of nursing assessment, observation and interventions. Intra-abdominal pressure (IAP) and abdominal compartment syndrome (ACS) have the potential to alter organ perfusion and compromise organ function. PMID:24499574

Nephrin phosphorylation regulates podocyte adhesion through the PINCH-1-ILK-α-parvin complex

PubMed Central

Zha, Dongqing; Chen, Cheng; Liang, Wei; Chen, Xinghua; Ma, Tean; Yang, Hongxia; van Goor, Harry; Ding, Guohua

2013-01-01

Nephrin, a structural molecule, is also a signaling molecule after phosphorylation. Inhibition of nephrin phosphorylation is correlated with podocyte injury. The PINCH-1-ILK-α-parvin (PIP) complex plays a crucial role in cell adhesion and cytoskeleton formation. We hypothesized that nephrin phosphorylation influenced cytoskeleton and cell adhesion in podocytes by regulating the PIP complex. The nephrin phosphorylation, PIP complex formation, and F-actin in Wistar rats intraperitoneally injected with puromycin aminonucleoside were gradually decreased but increased with time, coinciding with the recovery from glomerular/podocyte injury and proteinuria. In cultured podocytes, PIP complex knockdown resulted in cytoskeleton reorganization and decreased cell adhesion and spreading. Nephrin and its phosphorylation were unaffected after PIP complex knockdown. Furthermore, inhibition of nephrin phosphorylation suppressed PIP complex expression, disorganized podocyte cytoskeleton, and decreased cell adhesion and spreading. These findings indicate that alterations in nephrin phosphorylation disorganize podocyte cytoskeleton and decrease cell adhesion through a PIP complex-dependent mechanism. [BMB Reports 2013; 46(4): 230-235] PMID:23615266

Mechanisms for Flow-Enhanced Cell Adhesion

PubMed Central

Zhu, Cheng; Yago, Tadayuki; Lou, Jizhong; Zarnitsyna, Veronika I.; McEver, Rodger P.

2009-01-01

Cell adhesion is mediated by specific receptor—ligand bonds. In several biological systems, increasing flow has been observed to enhance cell adhesion despite the increasing dislodging fluid shear forces. Flow-enhanced cell adhesion includes several aspects: flow augments the initial tethering of flowing cells to a stationary surface, slows the velocity and increases the regularity of rolling cells, and increases the number of rollingly adherent cells. Mechanisms for this intriguing phenomenon may include transport-dependent acceleration of bond formation and force-dependent deceleration of bond dissociation. The former includes three distinct transport modes: sliding of cell bottom on the surface, Brownian motion of the cell, and rotational diffusion of the interacting molecules. The latter involves a recently demonstrated counterintuitive behavior called catch bonds where force prolongs rather than shortens the lifetimes of receptor—ligand bonds. In this article, we summarize our recently published data that used dimensional analysis and mutational analysis to elucidate the above mechanisms for flow-enhanced leukocyte adhesion mediated by L-selectinligand interactions. PMID:18299992

Inflammatory Cells and Proteases in Abdominal Aortic Aneurysm and its Complications.

PubMed

Haiying, Jiang; Sasaki, Takeshi; Jin, Enze; Kuzuya, Masafumi; Cheng, Xianwu

2018-05-30

Abdominal aortic aneurysm (AAA), a common disease among elderly individuals, involves the progressive dilatation of the abdominal aorta as a consequence of degeneration. The mechanisms of AAA formation, development and rupture are largely unknown. Surgical repair is the only available method of treatment since the lack of knowledge regarding the pathogenesis of AAA has hindered the development of suitable medical treatments, particularly the development of drugs. In this review, we describe the inflammatory cells and proteases that may be involved in the formation and development of AAA. This knowledge can contribute to the development of new drugs for AAA. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

De-adhesion dynamics of melanoma cells from brain endothelial layer.

PubMed

Varga, Béla; Domokos, Réka Anita; Fazakas, Csilla; Wilhelm, Imola; Krizbai, István A; Szegletes, Zsolt; Gergely, Csilla; Váró, György; Végh, Attila G

2018-03-01

Metastasis formation is a complex and not entirely understood process. The poorest prognosis and the most feared complications are associated to brain metastases. Melanoma derived brain metastases show the highest prevalence. Due to the lack of classical lymphatic drainage, in the process of brain metastases formation the haematogenous route is of primordial importance. The first and crucial step in this multistep process is the establishment of firm adhesion between the blood travelling melanoma cells and the tightly connected layer of the endothelium, which is the fundamental structure of the blood-brain barrier. This study compares the de-adhesion properties and dynamics of three melanoma cells types (WM35, A2058 and A375) to a confluent layer of brain micro-capillary endothelial cells. Cell type dependent adhesion characteristics are presented, pointing towards the existence of metastatic potential related nanomechanical aspects. Apparent mechanical properties such as elasticity, maximal adhesion force, number, size and distance of individual rupture events showed altered values pointing towards cell type dependent aspects. Our results underline the importance of mechanical details in case of intercellular interactions. Nevertheless, it suggests that in adequate circumstances elastic and adhesive characterizations might be used as biomarkers. Copyright © 2017. Published by Elsevier B.V.

[Use of Gastrografin(®) in the management of adhesion intestinal obstruction].

PubMed

Mora López, Laura; Serra-Aracil, Xavier; Llaquet Bayo, Heura; Navarro Soto, Salvador

2013-01-01

Adhesions are the most important cause of intestinal obstruction. Approximately 25% of surgical admissions for acute abdominal conditions are due to intestinal obstruction. Better diagnostic and treatment methods of intestinal obstruction could potentially reduce mortality rate to 5-10%. Gastrografin(®) could contribute to this achieve this. To present a protocol to treat adhesion intestinal obstruction with Gastrografin(®) that is safe, and allows shorter hospital stays and shorter time between admission and surgery. All patients with adhesion intestinal obstruction without symptoms of strangulation were treated with Gastrografin(®), intravenous fluids and nasogastric tube. Those in whom contrast reach the colon in 8, 12 or 24hours were considered to have partial obstruction, and were fed orally. If Gastrografin(®) failed in the following 24hours, a laparotomy was performed. Out of a total of 211 episodes (164 patients), 170 episodes received contrast and in 142 cases Gastrografin(®) reached the colon (104 episodes at 8h, 11 at 12h, and 27 at 24h). A laparotomy was required in 28 patients because of failed treatment, and in another 5 for other causes. A management protocol for adhesion intestinal obstruction with Gastrografin(®) is safe, reduces morbidity and mortality, and leads to a shorter hospital stay. Copyright © 2012 AEC. Published by Elsevier Espana. All rights reserved.

Methylene blue prevents surgery-induced peritoneal adhesions but impairs the early phase of anastomotic wound healing

PubMed Central

Dinc, Soykan; Ozaslan, Cihangir; Kuru, Bekir; Karaca, Sefa; Ustun, Huseyin; Alagol, Haluk; Renda, Nurten; Oz, Murat

2006-01-01

Objectives Adhesion formation continues to be an important problem in gastrointestinal surgery. In recent years, methylene blue (MB) has been reported to be an effective agent for preventing peritoneal adhesions. However, its effects on the wound healing process are unknown. In the present study, we investigated the effects of MB on the early and late phases of anastomotic wound healing and on adhesion formation. Methods We randomly categorized 92 rats into 2 groups in bursting pressure measurements and 50 rats into 3 groups in the adhesion model. We divided the animals into saline-treated (n = 46) or MB-treated (n = 46) groups. Bursting pressures of the anastomoses were measured on postoperative days 3 and 7. In biochemical studies, tissue hydroxyproline levels, total nitrite/nitrate levels and nitric oxide synthase activity were measured on postoperative days 3 and 7. In the adhesion model, we randomly categorized rats into sham (n = 10), saline-treated (n = 20) and MB-treated (n = 20) groups, and the formation of intraperitoneal adhesions was scored on postoperative day 14. We compared the measurement of bursting pressure and biochemical measurements of tissue hydroxyproline levels, total nitrite/nitrate levels and nitric oxide synthase activity. Histopathological findings of specimens were presented. Results During the early phase of wound healing (postoperative day 3), bursting pressures, tissue hydroxyproline, total nitrite/nitrate levels and nitric oxide synthase activity in the MB-treated group were significantly lower than those of the saline-treated group. On postoperative day 7, there was no significant difference in these parameters between MB and saline-treated groups. In the adhesion model, MB caused a significant reduction in the formation of peritoneal adhesions. Conclusion MB prevents peritoneal adhesions but causes a significant impairment of anastomotic bursting pressure during the early phase of the wound healing process by its transient

Effects of single- and multi-strain probiotics on biofilm formation and in vitro adhesion to bladder cells by urinary tract pathogens.

PubMed

Chapman, C M C; Gibson, G R; Rowland, I

2014-06-01

There is increasing evidence that probiotic bacteria can inhibit and/or prevent urinary tract infections. Possible mechanisms include prevention of adhesion of pathogens to the bladder epithelium and inhibition of biofilm formation. Currently there is interest in the comparative efficacy of single probiotics vs. strain mixtures. We have therefore tested the inhibitory activity of four single probiotics and four probiotic mixtures towards the urinary tract pathogens Escherichia coli NCTC 9001 and Enterococcus faecalis NCTC 00775. Inhibition of biofilm formation by cell-free supernatants was tested using the Crystal Violet assay, while prevention of pathogen adhesion to host cells was tested by using bladder cancer cells as a model for the human urinary tract. Under pH-controlled conditions, there was no significant inhibition of biofilm formation by any treatment. Without pH control, 5/8 treatments significantly inhibited biofilm production by E. coli, while 5/8 treatments inhibited production by E. faecalis. Using data from all Crystal Violet assays, there was no significant difference in the ability of single- and multi-strain probiotics to inhibit biofilm formation. In the cell culture assays, all treatments were able to significantly reduce numbers of pathogenic cells adhering to host cells by 2.5-3.5 logs. No significant difference was observed between the displacement caused by single strains and mixtures for either pathogen. Inhibition of biofilm seems to be a major mechanism of urinary tract pathogen exclusion, related to, and possibly dependent upon, the probiotic ability to reduce environmental pH. Exclusion via competition of binding sites is a possible in vivo mechanism for these probiotics. If an additive or synergistic effect exists between strains within a mixture, it does not manifest itself in a greater effect through these two inhibitory mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison of prosthetic materials for abdominal wall reconstruction in the presence of contamination and infection.

PubMed Central

Brown, G L; Richardson, J D; Malangoni, M A; Tobin, G R; Ackerman, D; Polk, H C

1985-01-01

Abdominal wall defects resulting from trauma, invasive infection, or hernia present a difficult problem for the surgeon. In order to study the problems associated with the prosthetic materials used for abdominal wall reconstruction, an animal model was used to simulate abdominal wall defects in the presence of peritonitis and invasive infection. One hundred guinea pigs were repaired with either polytetrafluorethylene (PTFE) or polypropylene mesh (PPM). Our experiments included intra-operative contamination with Staphylococcus aureus. We found significantly fewer organisms (p less than 0.05) adherent to the PTFE than to the PPM when antibiotics were administered after surgery, as well as when no antibiotics were given. In the presence of peritonitis, we found no real difference in numbers of intraperitoneal bacteria present whether PTFE or PPM was used. In all instances, the PTFE patches produced fewer adhesions and were more easily removed. From these experiments, it appears that PTFE may be associated with fewer problems than PPM in the presence of contamination and infection. Images FIG. 1. PMID:3159353

Wood : adhesives

Treesearch

A.H. Conner

2001-01-01

This chapter on wood adhesives includes: 1) Classification of wood adhesives 2) Thermosetting wood adhesives 3) Thermoplastic adhesives, 4) Wood adhesives based on natural sources 5) Nonconventional bonding of wood 6) Wood bonding.

Biologic meshes are not superior to synthetic meshes in ventral hernia repair: an experimental study with long-term follow-up evaluation.

PubMed

Ditzel, M; Deerenberg, E B; Grotenhuis, N; Harlaar, J J; Monkhorst, K; Bastiaansen-Jenniskens, Y M; Jeekel, J; Lange, J F

2013-10-01

In laparoscopic incisional hernia repair, direct contact between the prosthesis and the abdominal viscera is inevitable, which may lead to an inflammatory reaction resulting in abdominal adhesion formation. This study compared five different synthetic and biologic meshes in terms of adhesion formation, shrinkage, incorporation, and histologic characteristics after a period of 30 and 90 days. In 85 rats, a mesh was positioned intraperitoneally in direct contact with the viscera. Five different meshes were implanted: Prolene (polypropylene), Parietex composite (collagen-coated polyester), Strattice (porcine dermis, non-cross-linked), Surgisis (porcine small intestine submucosa, non-cross-linked), and Permacol (porcine dermis, cross-linked). The meshes were tested in terms of adhesion formation, shrinkage, and incorporation after a period of 30 and 90 days. Additionally, collagen formation after 90 days was determined. Significantly less adhesion formation was observed with Parietex composite (5 %; interquartile range [IQR], 2-5 %) and Strattice (5 %; IQR, 4-10 %) in the long term. In contrast, organs were attached to Permacol with four of seven meshes (57 %), and adhesion coverage of Surgisis mesh was present in 66 % (IQR, 0-100 %) of the cases. After 90 days, the best incorporation was seen with the Parietex composite mesh (79 %; IQR, 61-83 %). After 90 days, major alterations in adhesion formation were seen compared with 30 days. Histologically, Strattice and Parietex composite showed a new mesothelial layer on the visceral side of the mesh. Microscopic degradation and new collagen formation were seen in the Surgisis group. Parietex composite mesh demonstrated the best long-term results compared with all the other meshes. The biologic non-cross-linked mesh, Strattice, showed little adhesion formation and moderate shrinkage but poor incorporation. Biologic meshes are promising, but varying results require a more detailed investigation and demonstrate

Athletic injuries of the lateral abdominal wall: review of anatomy and MR imaging appearance.

PubMed

Stensby, J Derek; Baker, Jonathan C; Fox, Michael G

2016-02-01

The lateral abdominal wall is comprised of three muscles, each with a different function and orientation. The transversus abdominus, internal oblique, and external oblique muscles span the abdominal cavity between the iliocostalis lumborum and quadratus lumborum posteriorly and the rectus abdominis anteriorly. The lateral abdominal wall is bound superiorly by the lower ribs and costal cartilages and inferiorly by the iliac crest and inguinal ligament. The lateral abdominal wall may be acutely or chronically injured in a variety of athletic endeavors, with occasional acute injuries in the setting of high-energy trauma such as motor vehicle collisions. Injuries to the lateral abdominal wall may result in lumbar hernia formation, unique for its high incarceration rate, and also Spigelian hernias. This article will review the anatomy, the magnetic resonance (MR) imaging approach, and the features and complications of lateral abdominal wall injuries.

Abdominal epilepsy as an unusual cause of abdominal pain: a case report.

PubMed

Yunus, Yilmaz; Sefer, Ustebay; Dondu, Ulker Ustebay; Ismail, Ozanli; Yusuf, Ehi

2016-09-01

Abdominal pain, in etiology sometimes difficult to be defined, is a frequent complaint in childhood. Abdominal epilepsy is a rare cause of abdominal pain. In this article, we report on 5 year old girl patient with abdominal epilepsy. Some investigations (stool investigation, routine blood tests, ultrasonography (USG), electrocardiogram (ECHO) and electrocardiograpy (ECG), holter for 24hr.) were done to understand the origin of these complaints; but no abnormalities were found. Finally an EEG was done during an episode of abdominal pain and it was shown that there were generalized spikes especially precipitated by hyperventilation. The patient did well on valproic acid therapy and EEG was normal 1 month after beginning of the treatment. The cause of chronic recurrent paroxymal abdominal pain is difficult for the clinicians to diagnose in childhood. A lot of disease may lead to paroxysmal gastrointestinal symptoms like familial mediterranean fever and porfiria. Abdominal epilepsy is one of the rare but easily treatable cause of abdominal pain. In conclusion, abdominal epilepsy should be suspected in children with recurrent abdominal pain.

Coating Reduces Ice Adhesion

NASA Technical Reports Server (NTRS)

Smith, Trent; Prince, Michael; DwWeese, Charles; Curtis, Leslie

2008-01-01

The Shuttle Ice Liberation Coating (SILC) has been developed to reduce the adhesion of ice to surfaces on the space shuttle. SILC, when coated on a surface (foam, metal, epoxy primer, polymer surfaces), will reduce the adhesion of ice by as much as 90 percent as compared to the corresponding uncoated surface. This innovation is a durable coating that can withstand several cycles of ice growth and removal without loss of anti-adhesion properties. SILC is made of a binder composed of varying weight percents of siloxane(s), ethyl alcohol, ethyl sulfate, isopropyl alcohol, and of fine-particle polytetrafluoroethylene (PTFE). The combination of these components produces a coating with significantly improved weathering characteristics over the siloxane system alone. In some cases, the coating will delay ice formation and can reduce the amount of ice formed. SILC is not an ice prevention coating, but the very high water contact angle (greater than 140 ) causes water to readily run off the surface. This coating was designed for use at temperatures near -170 F (-112 C). Ice adhesion tests performed at temperatures from -170 to 20 F (-112 to -7 C) show that SILC is a very effective ice release coating. SILC can be left as applied (opaque) or buffed off until the surface appears clear. Energy dispersive spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS) data show that the coating is still present after buffing to transparency. This means SILC can be used to prevent ice adhesion even when coating windows or other objects, or items that require transmission of optical light. Car windshields are kept cleaner and SILC effectively mitigates rain and snow under driving conditions.

Pseudotumors after primary abdominal lipectomy as a new sequela in patients with abdominal apron.

PubMed

Dragu, Adrian; Bach, Alexander D; Polykandriotis, Elias; Kneser, Ulrich; Horch, Raymund E

2009-11-01

Malnutrition and overweight is a common problem in modern societies. Primary abdominal lipectomy is a standard surgical tool in patients with these problems. However, unknown secondary problems result from recent advances in obesity surgery. Plication of the anterior musculoaponeurotic wall is a widely and commonly used operative technique during abdominoplasty. Many different plication techniques have been published. So far no common standard and long-term effectiveness is proven. In addition, there is no sufficient literature dealing with the postoperative risks of plication of the musculoaponeurotic wall. Four patients with development of pseudotumors were reviewed. All four patients received 12 months in advance a primary abdominal lipectomy including a vertical plication of the musculoaponeurotic wall. All four patients were females with mean age of 61 years and mean body mass index (BMI) of 37 kg/m(2). All four patients had developed a pseudotumor of the abdomen as a long-term complication more than 12 months after primary abdominal lipectomy including a vertical plication of the anterior rectus sheath. One should be aware of the potential long-term risk of secondary postoperative hematoma formation, with or without partial necrosis of the anterior rectus sheath after vertical plication of the anterior musculoaponeurotic wall. Viewed clinically and radiologically, such sequelas may appear as pseudotumor like masses and require immediate revision.

Intra-Abdominal Hypertension and Abdominal Compartment Syndrome in Association with Ruptured Abdominal Aortic Aneurysm in the Endovascular Era: Vigilance Remains Critical

PubMed Central

Bozeman, Matthew C.; Ross, Charles B.

2012-01-01

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are common complications of ruptured abdominal aortoiliac aneurysms (rAAAs) and other abdominal vascular catastrophes even in the age of endovascular therapy. Morbidity and mortality due to systemic inflammatory response syndrome (SIRS) and multiple organ failure (MOF) are significant. Recognition and management of IAH are key critical care measures which may decrease morbidity and improve survival in these vascular patients. Two strategies have been utilized: expectant management with prompt decompressive laparotomy upon diagnosis of threshold levels of IAH versus prophylactic, delayed abdominal closure based upon clinical parameters at the time of initial repair. Competent management of the abdominal wound with preservation of abdominal domain is also an important component of the care of these patients. In this review, we describe published experience with IAH and ACS complicating abdominal vascular catastrophes, experience with ACS complicating endovascular repair of rAAAs, and techniques for management of the abdominal wound. Vigilance and appropriate management of IAH and ACS remains critically important in decreasing morbidity and optimizing survival following catastrophic intra-abdominal vascular events. PMID:22454763

Intra-abdominal hypertension and abdominal compartment syndrome in association with ruptured abdominal aortic aneurysm in the endovascular era: vigilance remains critical.

PubMed

Bozeman, Matthew C; Ross, Charles B

2012-01-01

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are common complications of ruptured abdominal aortoiliac aneurysms (rAAAs) and other abdominal vascular catastrophes even in the age of endovascular therapy. Morbidity and mortality due to systemic inflammatory response syndrome (SIRS) and multiple organ failure (MOF) are significant. Recognition and management of IAH are key critical care measures which may decrease morbidity and improve survival in these vascular patients. Two strategies have been utilized: expectant management with prompt decompressive laparotomy upon diagnosis of threshold levels of IAH versus prophylactic, delayed abdominal closure based upon clinical parameters at the time of initial repair. Competent management of the abdominal wound with preservation of abdominal domain is also an important component of the care of these patients. In this review, we describe published experience with IAH and ACS complicating abdominal vascular catastrophes, experience with ACS complicating endovascular repair of rAAAs, and techniques for management of the abdominal wound. Vigilance and appropriate management of IAH and ACS remains critically important in decreasing morbidity and optimizing survival following catastrophic intra-abdominal vascular events.

Abdominal Assessment.

PubMed

Fritz, Deborah; Weilitz, Pamela Becker

2016-03-01

Abdominal pain is one of the most common complaints by patients, and assessment of abdominal pain and associated symptoms can be challenging for home healthcare providers. Reasons for abdominal pain are related to inflammation, organ distention, and ischemia. The history and physical examination are important to narrow the source of acute or chronic problems, identify immediate interventions, and when necessary, facilitate emergency department care.

Inverted formin 2 in focal adhesions promotes dorsal stress fiber and fibrillar adhesion formation to drive extracellular matrix assembly

PubMed Central

Skau, Colleen T.; Plotnikov, Sergey V.; Doyle, Andrew D.; Waterman, Clare M.

2015-01-01

Actin filaments and integrin-based focal adhesions (FAs) form integrated systems that mediate dynamic cell interactions with their environment or other cells during migration, the immune response, and tissue morphogenesis. How adhesion-associated actin structures obtain their functional specificity is unclear. Here we show that the formin-family actin nucleator, inverted formin 2 (INF2), localizes specifically to FAs and dorsal stress fibers (SFs) in fibroblasts. High-resolution fluorescence microscopy and manipulation of INF2 levels in cells indicate that INF2 plays a critical role at the SF–FA junction by promoting actin polymerization via free barbed end generation and centripetal elongation of an FA-associated actin bundle to form dorsal SF. INF2 assembles into FAs during maturation rather than during their initial generation, and once there, acts to promote rapid FA elongation and maturation into tensin-containing fibrillar FAs in the cell center. We show that INF2 is required for fibroblasts to organize fibronectin into matrix fibers and ultimately 3D matrices. Collectively our results indicate an important role for the formin INF2 in specifying the function of fibrillar FAs through its ability to generate dorsal SFs. Thus, dorsal SFs and fibrillar FAs form a specific class of integrated adhesion-associated actin structure in fibroblasts that mediates generation and remodeling of ECM. PMID:25918420

Mechanical small bowel obstruction following a blunt abdominal trauma: A case report

PubMed Central

Zirak-Schmidt, Samira; El-Hussuna, Alaa

2015-01-01

Introduction Intestinal obstruction following abdominal trauma has previously been described. However, in most reported cases pathological finding was intestinal stenosis. Presentation of the case A 51-year-old male was admitted after a motor vehicle accident. Initial focused abdominal sonogram for trauma and enhanced computerized tomography were normal, however there was a fracture of the tibia. Three days later, he complained of abdominal pain, constipation, and vomiting. An exploratory laparotomy showed bleeding from the omentum and mechanical small bowel obstruction due to a fibrous band. Discussion The patient had prior abdominal surgery, but clinical and radiological findings indicate that the impact of the motor vehicle accident initiated his condition either by causing rotation of a bowel segment around the fibrous band, or by formation of a fibrous band secondary to minimal bleeding from the omentum. Conclusion High index of suspicion of intestinal obstruction is mandatory in trauma patients presenting with complaints of abdominal pain, vomiting, and constipation despite uneventful CT scan. PMID:26566436

Abdominal Aortic Aneurysm

MedlinePlus

... Kids and Teens Pregnancy and Childbirth Women Men Seniors Your Health Resources Healthcare Management End-of-Life ... familydoctor.org editorial staff Categories: Family Health, Men, Seniors, WomenTags: abdominal aorta, abdominal aortic aneurysm, abdominal pain, ...

Interactions with nanoscale topography: adhesion quantification and signal transduction in cells of osteogenic and multipotent lineage.

PubMed

Biggs, Manus J P; Richards, R Geoff; Gadegaard, Nikolaj; McMurray, Rebecca J; Affrossman, Stanley; Wilkinson, Chris D W; Oreffo, Richard O C; Dalby, Mathew J

2009-10-01

Polymeric medical devices widely used in orthopedic surgery play key roles in fracture fixation and orthopedic implant design. Topographical modification and surface micro-roughness of these devices regulate cellular adhesion, a process fundamental in the initiation of osteoinduction and osteogenesis. Advances in fabrication techniques have evolved the field of surface modification; in particular, nanotechnology has allowed the development of nanoscale substrates for the investigation into cell-nanofeature interactions. In this study human osteoblasts (HOBs) were cultured on ordered nanoscale pits and random nano "craters" and "islands". Adhesion subtypes were quantified by immunofluorescent microscopy and cell-substrate interactions investigated via immuno-scanning electron microscopy. To investigate the effects of these substrates on cellular function 1.7 k microarray analysis was used to establish gene profiles of enriched STRO-1+ progenitor cell populations cultured on these nanotopographies. Nanotopographies affected the formation of adhesions on experimental substrates. Adhesion formation was prominent on planar control substrates and reduced on nanocrater and nanoisland topographies; nanopits, however, were shown to inhibit directly the formation of large adhesions. STRO-1+ progenitor cells cultured on experimental substrates revealed significant changes in genetic expression. This study implicates nanotopographical modification as a significant modulator of osteoblast adhesion and cellular function in mesenchymal populations.

Tissue response to five commercially available peritoneal adhesion barriers-A systematic histological evaluation.

PubMed

Schmitt, Volker H; Mamilos, Andreas; Schmitt, Christine; Neitzer-Planck, Constanze N E; Rajab, Taufiek K; Hollemann, David; Wagner, Willi; Krämer, Bernhard; Hierlemann, Helmut; James Kirkpatrick, C; Brochhausen, Christoph

2018-02-01

Separating wounded serosa by physical barriers is the only clinically approved adjunct for postoperative adhesion prevention. Since the optimal adhesion barrier has not been found, it is essential to improve our pathogenic understanding of adhesion formation and to compare the effects of different barrier materials on tissue and cells. Wistar rats underwent standardized peritoneal damage and were treated either with Seprafilm, Adept, Intercoat, Spraygel, SupraSeal or remained untreated as a control. 14 days postoperatively, the lesions were explanted and histomorphologically analyzed using the European ISO score to evaluate material implants. Striking differences between the material groups were present regarding the inflammation, fibrosis, and foreign body reaction. According to the ISO score, Intercoat and Spraygel were considered as nonirritating to tissue. Adept, Seprafilm, and SupraSeal were assessed as mild-irritating materials. Interestingly, the most effective material in adhesion prevention revealed moderate inflammation accompanied by minor fibrosis. The degree of inflammation to barrier materials does not predict the efficacy in the prevention of adhesions. Histopathological investigations are crucial to improve our understanding of the cellular mechanisms during adhesion formation and elucidate the tissue response to material approaches used in adhesion prevention. This will lead to improved antiadhesive strategies and the development of functional barrier biomaterials. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 598-609, 2018. © 2017 Wiley Periodicals, Inc.

Liquefaction of kenaf (Hibiscus cannabinus L.) core for wood laminating adhesive.

PubMed

Juhaida, M F; Paridah, M T; Mohd Hilmi, M; Sarani, Z; Jalaluddin, H; Mohamad Zaki, A R

2010-02-01

A study was carried out to produce polyurethane (PU) as a wood laminating adhesive from liquefied kenaf core (LKC) polyols by reacting it with toluene-2,4-diisocyanate (TDI) and 1,4-butanediol (BDO). The LKC polyurethane (LKCPU) adhesive has a molecular weight (MW) of 2666, viscosity of 5370 mPa s, and solids content of 86.9%. The average shear strength of the rubberwood (RW) bonded with LKCPU adhesive was 2.9 MPa. Most of the sheared specimens experienced a total adhesive failure. The formation of air bubbles through the liberation of carbon dioxide was observed to reduce the adhesive penetration and bonding strength which was obviously seen on the sheared specimens. The percentage of catalyst used can be varied based on the usage and working time needed. Nonetheless, the physical properties of LKCPU produced in this work had shown good potential as edge-bonding adhesive.

Adhesion, friction, and wear of a copper bicrystal with (111) and (210) grains

NASA Technical Reports Server (NTRS)

Brainard, W. A.; Buckley, D. H.

1973-01-01

Sliding friction experiments were conducted in air with polycrystalline copper and ruby riders sliding against a copper bicrystal. Friction coefficient was measured across the bicrystal surface, and the initiation of adhesive wear was examined with scanning electron microscopy. Results indicate a marked increase in friction coefficient as the copper rider crossed the grain boundary from the (111) plane to the (210) plane of the bicrystal. Adhesion, friction, and initiation of adhesive wear was notably different in the adjacent grains of differing orientation. A slip-band adhesion-generated fracture mechanism for wear particle formation is proposed.

Topical non-barrier agents for postoperative adhesion prevention in animal models.

PubMed

Imai, Atsushi; Suzuki, Noriko

2010-04-01

Pelvic adhesion can form as a result of inflammation, endometriosis or surgical trauma. Most surgical procedures performed by obstetrician-gynecologists are associated with pelvic adhesions that may cause subsequent serious sequelae, including small bowel obstruction, infertility, chronic pelvic pain, and difficulty in postoperative treatment, including complexity during subsequent surgical procedures. An increasing number of adhesion reduction agents, in the form of site-specific and broad-coverage barriers and solutions, are becoming available to surgical teams. The most widely studied strategies include placing synthetic barrier agents between the pelvic structures. Most of the adhesions in the barrier-treated patients develop in uncovered areas in the abdomen. This fact suggests that the application of liquid or gel anti-adhesive agents to cover all potential peritoneal lesions, together with the use of barrier agents, may reduce the formation of postoperative adhesions. This article introduces the topical choices available for adhesion prevention mentioned in preliminary clinical applications and animal models. To date there is no substantial evidence that their use reduces the incidence of postoperative adhesions. In combination with good surgical techniques, these non-barrier agents may play an important role in adhesion reduction. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Bologna guidelines for diagnosis and management of adhesive small bowel obstruction (ASBO): 2017 update of the evidence-based guidelines from the world society of emergency surgery ASBO working group.

PubMed

Ten Broek, Richard P G; Krielen, Pepijn; Di Saverio, Salomone; Coccolini, Federico; Biffl, Walter L; Ansaloni, Luca; Velmahos, George C; Sartelli, Massimo; Fraga, Gustavo P; Kelly, Michael D; Moore, Frederick A; Peitzman, Andrew B; Leppaniemi, Ari; Moore, Ernest E; Jeekel, Johannes; Kluger, Yoram; Sugrue, Michael; Balogh, Zsolt J; Bendinelli, Cino; Civil, Ian; Coimbra, Raul; De Moya, Mark; Ferrada, Paula; Inaba, Kenji; Ivatury, Rao; Latifi, Rifat; Kashuk, Jeffry L; Kirkpatrick, Andrew W; Maier, Ron; Rizoli, Sandro; Sakakushev, Boris; Scalea, Thomas; Søreide, Kjetil; Weber, Dieter; Wani, Imtiaz; Abu-Zidan, Fikri M; De'Angelis, Nicola; Piscioneri, Frank; Galante, Joseph M; Catena, Fausto; van Goor, Harry

2018-01-01

Adhesive small bowel obstruction (ASBO) is a common surgical emergency, causing high morbidity and even some mortality. The adhesions causing such bowel obstructions are typically the footprints of previous abdominal surgical procedures. The present paper presents a revised version of the Bologna guidelines to evidence-based diagnosis and treatment of ASBO. The working group has added paragraphs on prevention of ASBO and special patient groups. The guideline was written under the auspices of the World Society of Emergency Surgery by the ASBO working group. A systematic literature search was performed prior to the update of the guidelines to identify relevant new papers on epidemiology, diagnosis, and treatment of ASBO. Literature was critically appraised according to an evidence-based guideline development method. Final recommendations were approved by the workgroup, taking into account the level of evidence of the conclusion. Adhesion formation might be reduced by minimally invasive surgical techniques and the use of adhesion barriers. Non-operative treatment is effective in most patients with ASBO. Contraindications for non-operative treatment include peritonitis, strangulation, and ischemia. When the adhesive etiology of obstruction is unsure, or when contraindications for non-operative management might be present, CT is the diagnostic technique of choice. The principles of non-operative treatment are nil per os, naso-gastric, or long-tube decompression, and intravenous supplementation with fluids and electrolytes. When operative treatment is required, a laparoscopic approach may be beneficial for selected cases of simple ASBO.Younger patients have a higher lifetime risk for recurrent ASBO and might therefore benefit from application of adhesion barriers as both primary and secondary prevention. This guideline presents recommendations that can be used by surgeons who treat patients with ASBO. Scientific evidence for some aspects of ASBO management is scarce, in

Intra-abdominal hypertension and abdominal compartment syndrome in pediatrics. A review.

PubMed

Thabet, Farah Chedly; Ejike, Janeth Chiaka

2017-10-01

To consolidate pediatric intensivists' understanding of the pathophysiology, definition, incidence, monitoring, and management of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS); and to highlight the characteristics related to the pediatric population. This is a narrative review article that utilized a systematic search of the medical literature published in the English language between January 1990 and august 2016. Studies were identified by conducting a comprehensive search of Pub Med databases. Search terms included "intra-abdominal hypertension and child", "intra-abdominal hypertension and pediatrics", "abdominal compartment syndrome and child", and "abdominal compartment syndrome and pediatrics". Intra-abdominal hypertension and ACS are associated with a number of pathophysiological disturbances and increased morbidity and mortality. These conditions have been well described in critically ill adults. In children, the IAH and the ACS have a reported incidence of 13% and 0.6 to 10% respectively; they carry similar prognostic impact but are still under-diagnosed and under-recognized by pediatric health care providers. Intra-abdominal hypertension and ACS are conditions that are regularly encountered in critically ill children. They are associated with an increased morbidity and mortality. Early recognition, prevention and timely management of this critical condition are necessary to improve its outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

Plain abdominal radiography in acute abdominal pain; past, present, and future

PubMed Central

Gans, Sarah L; Stoker, Jaap; Boermeester, Marja A

2012-01-01

Several studies have demonstrated that a diagnosis based solely on a patient’s medical history, physical examination, and laboratory tests is not reliable enough, despite the fact that these aspects are essential parts of the workup of a patient presenting with acute abdominal pain. Traditionally, imaging workup starts with abdominal radiography. However, numerous studies have demonstrated low sensitivity and accuracy for plain abdominal radiography in the evaluation of acute abdominal pain as well as various specific diseases such as perforated viscus, bowel obstruction, ingested foreign body, and ureteral stones. Computed tomography, and in particular computed tomography after negative ultrasonography, provides a better workup than plain abdominal radiography alone. The benefits of computed tomography lie in decision-making for management, planning of a surgical strategy, and possibly even avoidance of negative laparotomies. Based on abundant available evidence, major advances in diagnostic imaging, and changes in the management of certain diseases, we can conclude that there is no place for plain abdominal radiography in the workup of adult patients with acute abdominal pain presenting in the emergency department in current practice. PMID:22807640

21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that consists...

21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that consists...

21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that consists...

21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that consists...

21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that consists...

The effective control of a bleeding injury using a medical adhesive containing batroxobin.

PubMed

You, Kyung Eun; Koo, Min-Ah; Lee, Dae-Hyung; Kwon, Byeong-Ju; Lee, Mi Hee; Hyon, Suong-Hyu; Seomun, Young; Kim, Jong-Tak; Park, Jong-Chul

2014-04-01

Many types of hemostatic agents have been studied for the effective control of bleeding. In this study, a powdery medical adhesive composed of aldehyded dextran and ε-poly (L-lysine) was used with the recombinant batroxobin. Batroxobin is a venomous component from the snake Bothrops atrox moojeni and catalyzes fibrinogen conversion to form soluble fibrin clots. This research aims to examine the performance of the batroxobin-containing adhesive for hemostasis, and evaluate its potential as a novel hemostatic adhesive. The fibrinogen conversion ability of batroxobin was evaluated by a fibrinogen clotting assay and a whole blood clotting assay. Both experiments demonstrated the effectiveness of the batroxobin-containing adhesive for blood clot formation. Animal experiments were also conducted. After a pricking wound was made in an ICR (imprinting control region) mouse liver, the adhesive and various concentrations of batroxobin were applied. The total amount of blood loss was reduced with increasing concentrations of batroxobin. For excessive bleeding conditions, the femoral artery wound model of SD (Sprague-Dawley) rats was adopted. With higher concentrations of batroxobin, hemostasis was more rapidly achieved. Histological analysis of the liver model also supports the hemostatic effects through fibrin clot formation. In conclusion, batroxobin and medical adhesive effectively facilitate blood coagulation, and could be developed for clinical use.

Abdominal Trauma Revisited.

PubMed

Feliciano, David V

2017-11-01

Although abdominal trauma has been described since antiquity, formal laparotomies for trauma were not performed until the 1800s. Even with the introduction of general anesthesia in the United States during the years 1842 to 1846, laparotomies for abdominal trauma were not performed during the Civil War. The first laparotomy for an abdominal gunshot wound in the United States was finally performed in New York City in 1884. An aggressive operative approach to all forms of abdominal trauma till the establishment of formal trauma centers (where data were analyzed) resulted in extraordinarily high rates of nontherapeutic laparotomies from the 1880s to the 1960s. More selective operative approaches to patients with abdominal stab wounds (1960s), blunt trauma (1970s), and gunshot wounds (1990s) were then developed. Current adjuncts to the diagnosis of abdominal trauma when serial physical examinations are unreliable include the following: 1) diagnostic peritoneal tap/lavage, 2) surgeon-performed ultrasound examination; 3) contrast-enhanced CT of the abdomen and pelvis; and 4) diagnostic laparoscopy. Operative techniques for injuries to the liver, spleen, duodenum, and pancreas have been refined considerably since World War II. These need to be emphasized repeatedly in an era when fewer patients undergo laparotomy for abdominal trauma. Finally, abdominal trauma damage control is a valuable operative approach in patients with physiologic exhaustion and multiple injuries.

Adhesion

MedlinePlus

... Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Adhesion URL of this page: //medlineplus.gov/ency/article/001493.htm Adhesion To use the sharing features on this page, please enable JavaScript. Adhesions are bands of scar-like tissue that form between two ...

[The role of fibronectin in adhesion of corynebacteria to vaginal epitheliocytes].

PubMed

Gladysheva, I V; Cherkasov, S V

2014-01-01

Determination of the role of fibronectin in adhesion of corynebacteria to vaginal epitheliocytes. Corynebacterium genus microorganisms and primary epitheliocytes isolated from the lower reproductive tract of women were used. Adhesive ability of corynebacteria was studied in polystyrene plates against fixed fibronectin and on the model of vaginal epitheliocytes. Changes in adhesion of corynebacteria to vaginal epitheliocytes was evaluated after treatment of the latter with fibronectin. All the studied strains had the adhesion ability to fibronectin and vaginal epitheliocytes. The same strains were attributed to groups of high, moderate or low adhesive using both plate method and method utilizing vaginal epitheliocytes model, that tells of their comparability. During the addition of fibronectin to epitheliocytes, an enhancement of adhesion of all the studied corynebacteria strains took place. Adhesion index in strains isolated from healthy women increased by an average of 46.6%, adhesion index by 10.5 bact. cells/epith. In strains isolated from women with micro-ecologic disruption, adhesion increase was by 15.3% and 4.9 bact. cells/epith., respectively. Fibronectin is a factor that determines adhesion of corynebacteria to vaginal epitheliocytes and thus is important for formation of associative symbiosis of reproductive tract of women. The data obtained open perspective of use of fibronectin with the aim of colonizing ability increase of probiotics.

Comparison of Arterial Repair through the Suture, Suture with Fibrin or Cyanoacrylate Adhesive in Ex-Vivo Porcine Aortic Segment

PubMed Central

de Carvalho, Marcus Vinicius H.; Marchi, Evaldo; Lourenço, Edmir Américo

2017-01-01

Introduction Tissue adhesives can be used as adjacent to sutures to drop or avoid bleeding in cardiovascular operations. Objective To verify the efficiency of fibrin and cyanoacrylate adhesive to seal arterial sutures and if the adhesives penetrate through suture line to the inner of arteries. Methods 20 abdominal aorta segments of pigs were divided into two groups according to the adhesive which would be used as adjacent to the suture. In every arterial segment an arteriotomy was done, followed by a conventional artery closure. Afterwards a colloidal fluid was injected inside the arterial segment with a simultaneous intravascular pressure monitoring up to a fluid leakage through the suture. This procedure was repeated after application of one of the adhesives on the suture in order to check if the bursting pressure increases. The inner aorta segments also were analyzed in order to check if there was intraluminal adhesive penetration. Results In Suture 1 group, the mean arterial pressure sustained by the arterial suture reached 86±5.35 mmHg and after the fibrin adhesive application reached 104±11.96 (P<0.002). In the Suture 2 group, the mean arterial pressure sustained by the suture reached 83±2.67 mmHg and after the cyanoacrylate adhesive application reached 152±14.58 mmHg (P<0.002). Intraluminal adhesive penetration has not been noticed. Conclusion There was a significant rise in the bursting pressure when tissue adhesives were used as adjacent to arterial suture, and this rise was higher if the cyanoacrylate adhesive was used. In addition, the adhesives do not penetrate through the suture line into the arteries. PMID:29267611

Management of complex abdominal wall defects associated with penetrating abdominal trauma.

PubMed

Arul, G Suren; Sonka, B J; Lundy, J B; Rickard, R F; Jeffery, S L A

2015-03-01

The paradigm of Damage Control Surgery (DCS) has radically improved the management of abdominal trauma, but less well described are the options for managing the abdominal wall itself in an austere environment. This article describes a series of patients with complex abdominal wall problems managed at the UK-led Role 3 Medical Treatment Facility (MTF) in Camp Bastion, Afghanistan. Contemporaneous review of a series of patients with complex abdominal wall injuries who presented to the Role 3 MTF between July and November 2012. Five patients with penetrating abdominal trauma associated with significant damage to the abdominal wall were included. All patients were managed using DCS principles, leaving the abdominal wall open at the end of the first procedure. Subsequent management of the abdominal wall was determined by a multidisciplinary team of general and plastic surgeons, intensivists and specialist nurses. The principles of management identified included minimising tissue loss on initial laparotomy by joining adjacent wounds and marginal debridement of dead tissue; contraction of the abdominal wall was minimised by using topical negative pressure dressing and dermal-holding sutures. Definitive closure was timed to allow oedema to settle and sepsis to be controlled. Closure techniques include delayed primary closure with traction sutures, components separation, and mesh closure with skin grafting. A daily multidisciplinary team discussion was invaluable for optimal decision making regarding the most appropriate means of abdominal closure. Dermal-holding sutures were particularly useful in preventing myostatic contraction of the abdominal wall. A simple flow chart was developed to aid decision making in these patients. This flow chart may prove especially useful in a resource-limited environment in which returning months or years later for closure of a large ventral hernia may not be possible. Published by the BMJ Publishing Group Limited. For permission to use

Switchable Adhesion in Vacuum Using Bio-Inspired Dry Adhesives.

PubMed

Purtov, Julia; Frensemeier, Mareike; Kroner, Elmar

2015-11-04

Suction based attachment systems for pick and place handling of fragile objects like glass plates or optical lenses are energy-consuming and noisy and fail at reduced air pressure, which is essential, e.g., in chemical and physical vapor deposition processes. Recently, an alternative approach toward reversible adhesion of sensitive objects based on bioinspired dry adhesive structures has emerged. There, the switching in adhesion is achieved by a reversible buckling of adhesive pillar structures. In this study, we demonstrate that these adhesives are capable of switching adhesion not only in ambient air conditions but also in vacuum. Our bioinspired patterned adhesive with an area of 1 cm(2) provided an adhesion force of 2.6 N ± 0.2 N in air, which was reduced to 1.9 N ± 0.2 N if measured in vacuum. Detachment was induced by buckling of the structures due to a high compressive preload and occurred, independent of air pressure, at approximately 0.9 N ± 0.1 N. The switch in adhesion was observed at a compressive preload between 5.6 and 6.0 N and was independent of air pressure. The difference between maximum adhesion force and adhesion force after buckling gives a reasonable window of operation for pick and place processes. High reversibility of the switching behavior is shown over 50 cycles in air and in vacuum, making the bioinspired switchable adhesive applicable for handling operations of fragile objects.

Switchable Adhesion in Vacuum Using Bio-Inspired Dry Adhesives

PubMed Central

2015-01-01

Suction based attachment systems for pick and place handling of fragile objects like glass plates or optical lenses are energy-consuming and noisy and fail at reduced air pressure, which is essential, e.g., in chemical and physical vapor deposition processes. Recently, an alternative approach toward reversible adhesion of sensitive objects based on bioinspired dry adhesive structures has emerged. There, the switching in adhesion is achieved by a reversible buckling of adhesive pillar structures. In this study, we demonstrate that these adhesives are capable of switching adhesion not only in ambient air conditions but also in vacuum. Our bioinspired patterned adhesive with an area of 1 cm2 provided an adhesion force of 2.6 N ± 0.2 N in air, which was reduced to 1.9 N ± 0.2 N if measured in vacuum. Detachment was induced by buckling of the structures due to a high compressive preload and occurred, independent of air pressure, at approximately 0.9 N ± 0.1 N. The switch in adhesion was observed at a compressive preload between 5.6 and 6.0 N and was independent of air pressure. The difference between maximum adhesion force and adhesion force after buckling gives a reasonable window of operation for pick and place processes. High reversibility of the switching behavior is shown over 50 cycles in air and in vacuum, making the bioinspired switchable adhesive applicable for handling operations of fragile objects. PMID:26457864

The value of plain abdominal radiographs in management of abdominal emergencies in Luth.

PubMed

Ashindoitiang, J A; Atoyebi, A O; Arogundade, R A

2008-01-01

The plain abdominal x-ray is still the first imaging modality in diagnosis of acute abdomen. The aim of this study was to find the value of plain abdominal x-ray in the management of abdominal emergencies seen in Lagos university teaching hospital. The accurate diagnosis of the cause of acute abdominal pain is one of the most challenging undertakings in emergency medicine. This is due to overlapping of clinical presentation and non-specific findings of physical and even laboratory data of the multifarious causes. Plain abdominal radiography is one investigation that can be obtained readily and within a short period of time to help the physician arrive at a correct diagnosis The relevance of plain abdominal radiography was therefore evaluated in the management of abdominal emergencies seen in Lagos over a 12 month period (April 2002 to March 2003). A prospective study of 100 consecutively presenting patients with acute abdominal conditions treated by the general surgical unit of Lagos University Teaching Hospital was undertaken. All patients had supine and erect abdominal x-ray before any therapeutic intervention was undertaken. The diagnostic features of the plain films were compared with final diagnosis to determine the usefulness of the plain x-ray There were 54 males and 46 females (M:F 1.2:1). Twenty-four percent of the patients had intestinal obstruction, 20% perforated typhoid enteritis; gunshot injuries and generalized peritonitis each occurred in 13%, blunt abdominal trauma in 12%, while 8% and 10% had acute appendicitis and perforated peptic ulcer disease respectively. Of 100 patients studied, 54% had plain abdominal radiographs that showed positive diagnostic features. Plain abdominal radiograph showed high sensitivity in patients with intestinal obstruction 100% and perforated peptic ulcer 90% but was less sensitive in patients with perforated typhoid, acute appendicitis, and blunt abdominal trauma and generalized peritonitis. In conclusion, this study

d(-) Lactic Acid-Induced Adhesion of Bovine Neutrophils onto Endothelial Cells Is Dependent on Neutrophils Extracellular Traps Formation and CD11b Expression.

PubMed

Alarcón, Pablo; Manosalva, Carolina; Conejeros, Ivan; Carretta, María D; Muñoz-Caro, Tamara; Silva, Liliana M R; Taubert, Anja; Hermosilla, Carlos; Hidalgo, María A; Burgos, Rafael A

2017-01-01

Bovine ruminal acidosis is of economic importance as it contributes to reduced milk and meat production. This phenomenon is mainly attributed to an overload of highly fermentable carbohydrate, resulting in increased d(-) lactic acid levels in serum and plasma. Ruminal acidosis correlates with elevated acute phase proteins in blood, along with neutrophil activation and infiltration into various tissues leading to laminitis and aseptic polysynovitis. Previous studies in bovine neutrophils indicated that d(-) lactic acid decreased expression of L-selectin and increased expression of CD11b to concentrations higher than 6 mM, suggesting a potential role in neutrophil adhesion onto endothelia. The two aims of this study were to evaluate whether d(-) lactic acid influenced neutrophil and endothelial adhesion and to trigger neutrophil extracellular trap (NET) production (NETosis) in exposed neutrophils. Exposure of bovine neutrophils to 5 mM d(-) lactic acid elevated NET release compared to unstimulated neutrophil negative controls. Moreover, this NET contains CD11b and histone H 4 citrullinated, the latter was dependent on PAD4 activation, a critical enzyme in DNA decondensation and NETosis. Furthermore, NET formation was dependent on d(-) lactic acid plasma membrane transport through monocarboxylate transporter 1 (MCT1). d(-) lactic acid enhanced neutrophil adhesion onto endothelial sheets as demonstrated by in vitro neutrophil adhesion assays under continuous physiological flow conditions, indicating that cell adhesion was a NET- and a CD11b/ICAM-1-dependent process. Finally, d(-) lactic acid was demonstrated for the first time to trigger NETosis in a PAD4- and MCT1-dependent manner. Thus, d(-) lactic acid-mediated neutrophil activation may contribute to neutrophil-derived pro-inflammatory processes, such as aseptic laminitis and/or polysynovitis in animals suffering acute ruminal acidosis.

Mapping cell surface adhesion by rotation tracking and adhesion footprinting

NASA Astrophysics Data System (ADS)

Li, Isaac T. S.; Ha, Taekjip; Chemla, Yann R.

2017-03-01

Rolling adhesion, in which cells passively roll along surfaces under shear flow, is a critical process involved in inflammatory responses and cancer metastasis. Surface adhesion properties regulated by adhesion receptors and membrane tethers are critical in understanding cell rolling behavior. Locally, adhesion molecules are distributed at the tips of membrane tethers. However, how functional adhesion properties are globally distributed on the individual cell’s surface is unknown. Here, we developed a label-free technique to determine the spatial distribution of adhesive properties on rolling cell surfaces. Using dark-field imaging and particle tracking, we extract the rotational motion of individual rolling cells. The rotational information allows us to construct an adhesion map along the contact circumference of a single cell. To complement this approach, we also developed a fluorescent adhesion footprint assay to record the molecular adhesion events from cell rolling. Applying the combination of the two methods on human promyelocytic leukemia cells, our results surprisingly reveal that adhesion is non-uniformly distributed in patches on the cell surfaces. Our label-free adhesion mapping methods are applicable to the variety of cell types that undergo rolling adhesion and provide a quantitative picture of cell surface adhesion at the functional and molecular level.

Evaluation of the levels of metalloproteinsase-2 in patients with abdominal aneurysm and abdominal hernias.

PubMed

Antoszewska, Magdalena

2013-05-01

Abdominal aortic aneurysms and abdominal hernias become an important health problems of our times. Abdominal aortic aneurysm and its rupture is one of the most dangerous fact in vascular surgery. There are some theories pointing to a multifactoral genesis of these kinds of diseases, all of them assume the attenuation of abdominal fascia and abdominal aortic wall. The density and continuity of these structures depend on collagen and elastic fibers structure. Reducing the strength of the fibers may be due to changes in the extracellular matrix (ECM) by the proteolytic enzymes-matrix metalloproteinases (MMPs) that degrade extracellular matrix proteins. These enzymes play an important role in the development of many disease: malignant tumors (colon, breast, lung, pancreas), cardiovascular disease (myocardial infarction, ischemia-reperfusion injury), connective tissue diseases (Ehler-Danlos Syndrome, Marfan's Syndrome), complications of diabetes (retinopathy, nephropathy). One of the most important is matrix metalloproteinase-2 (MMP-2). The aim of the study was an estimation of the MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia, and in patients with only abdominal aortic aneurysm. The study involved 88 patients aged 42 to 89 years, including 75 men and 13 women. Patients were divided into two groups: patients with abdominal aortic aneurysm and primary abdominal hernia (45 persons, representing 51.1% of all group) and patients with only abdominal aortic aneurysm (43 persons, representing 48,9% of all group). It was a statistically significant increase in MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia compared to patients with only abdominal aortic aneurysm. It was a statistically significant increase in the prevalence of POCHP in patients with only abdominal aortic aneurysm compared to patients with abdominal aortic aneurysm and primary abdominal hernia. Statistically significant

Wood adhesion and adhesives

Treesearch

Charles R. Frihart

2005-01-01

An appreciation of rheology, material science, organic chemistry, polymer science, and mechanics leads to better understanding of the factors controlling the performance of the bonded assemblies. Given the complexity of wood as a substrate, it is hard to understand why some wood adhesives work better than other wood adhesives, especially when under the more severe...

[The role of estrogen in the formation and development of abdominal aortic aneurysm: experiment with rats].

PubMed

Wu, Xiao-fei; Zhang, Jian; Xin, Shi-jie; Duan, Zhi-quan; Zhang, Gong

2007-02-13

To investigate the role of estrogen in the formation and development of abdominal aortic aneurysm (AAA). Twenty male Wistar rats were randomly divided into 2 equal groups: experiment group, injected with 17-beta estradiol (E2) intraperitoneally 1 week before the establishment of AAA once a day for 3 weeks (until 2 weeks after the establishment of AAA), and underwent infusion of pancreatic elastase into the infrarenal abdominal aorta through a catheter inserted into the left common iliac artery o as to establish the AAA model, and control group, injected with normal saline intraperitoneally for 3 weeks. Two weeks after the establishment of AAA model, the rats underwent laparotomy, blood samples were collected from vena cava inferior to detect the level of E2 by radioimmunoassay and then the aneurysms were harvested to undergo immunohistochemistry and real-time PCR to detect the protein expression and mRNA expression of matrix metalloproteinase (MMP)-2 and MMP-9. The plasma E2 level of the experiment group was (28+/-6) pg/ml, significantly higher than that of the control group [(5.86+/-0.24) pg/ml, P<0.01]. The aorta dilatation rate of the experiment group was (103+/-4)%, significantly lower than that of the control group [(172+/-13)%, P<0.01]. The destruction of arterial wall, degradation of elastic fibers, and infiltration of inflammatory cells were all more severe in the control group than in the experiment group. The relative mRNA expression of MMP-2 of the experiment group was 0.07+/-0.04, significantly lower than that of the control group (0.22+/-0.07, P<0.01); and the relative mRNA expression of MMP-9 of the experiment group was 1.4+/-0.7, significantly lower than that of the control group (7.4+/-2.8, P<0.01). The protein expression of MMP-2 of the experiment group was (22+/-3)%, significantly lower than that of the control group [(50+/-12)%, P<0.01], and the protein expression of MMP-9 of the experiment group was (23+/-2)%, significantly lower than that of

Surface characterization and adhesion of oxygen plasma-modified LARC-TPI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chin, J.W.; Wightman, J.P.

1992-01-01

LARC-TPI, an aromatic thermoplastic polyimide, was exposed to an oxygen plasma as a surface pretreatment of adhesive bonding. Chemical and physical changes which occurred in the polyimide surface as a result of the plasma treatment were investigated using X-ray photoelectron spectroscopy (XPS), infrared reflection-absorption spectroscopy (IR-RAS), contact angle analysis, ellipsometry and high resolution scanning electron microscopy (HR-SEM). A 180{degree} peel test with an acrylate-based pressure sensitive adhesive as a flexible adherend was utilized to study the interactions of the plasma-treated polyimide surface with other polymeric materials. The surface characterization and adhesion testing results showed that the oxygen plasma treatment, whilemore » creating a more hydrophilic, polar surface, also caused chain scission resulting in the formation of a weak boundary layer which inhibited adhesion.« less

[A commonly seen cause of abdominal pain: abdominal cutaneous nerve entrapment syndrome].

PubMed

Solmaz, Ilker; Talay, Mustafa; Tekindur, Şükrü; Kurt, Ercan

2012-01-01

Although abdominal cutaneous nerve entrapment syndrome (ACNES) is accepted as a rare condition, it is a syndrome that should be diagnosed more commonly when the clinical signs cannot explain the cause of abdominal pain. Abdominal pain is commonly considered by physicians to be based on intra-abdominal causes. Consequently, redundant tests and consultations are requested for these patients, and unnecessary surgical procedures may be applied. Patients with this type of pain are consulted to many clinics, and because their definitive diagnoses cannot be achieved, they are assessed as psychiatric patients. Actually, a common cause of abdominal wall pain is nerve entrapment on the lateral edge of the rectus abdominis muscle. In this paper, we would like to share information about the diagnosis and treatment of a patient who, prior to presenting to us, had applied to different clinics for chronic abdominal pain and had undergone many tests and consultations; abdominal surgery was eventually decided.

Effect of Loading History on Airway Smooth Muscle Cell-Matrix Adhesions.

PubMed

Irons, Linda; Owen, Markus R; O'Dea, Reuben D; Brook, Bindi S

2018-06-05

Integrin-mediated adhesions between airway smooth muscle (ASM) cells and the extracellular matrix (ECM) regulate how contractile forces generated within the cell are transmitted to its external environment. Environmental cues are known to influence the formation, size, and survival of cell-matrix adhesions, but it is not yet known how they are affected by dynamic fluctuations associated with tidal breathing in the intact airway. Here, we develop two closely related theoretical models to study adhesion dynamics in response to oscillatory loading of the ECM, representing the dynamic environment of ASM cells in vivo. Using a discrete stochastic-elastic model, we simulate individual integrin binding and rupture events and observe two stable regimes in which either bond formation or bond rupture dominate, depending on the amplitude of the oscillatory loading. These regimes have either a high or low fraction of persistent adhesions, which could affect the level of strain transmission between contracted ASM cells and the airway tissue. For intermediate loading, we observe a region of bistability and hysteresis due to shared loading between existing bonds; the level of adhesion depends on the loading history. These findings are replicated in a related continuum model, which we use to investigate the effect of perturbations mimicking deep inspirations (DIs). Because of the bistability, a DI applied to the high adhesion state could either induce a permanent switch to a lower adhesion state or allow a return of the system to the high adhesion state. Transitions between states are further influenced by the frequency of oscillations, cytoskeletal or ECM stiffnesses, and binding affinities, which modify the magnitudes of the stable adhesion states as well as the region of bistability. These findings could explain (in part) the transient bronchodilatory effect of a DI observed in asthmatics compared to a more sustained effect in normal subjects. Copyright © 2018 Biophysical

Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis.

PubMed

Goh, Qingnian; Dearth, Christopher L; Corbett, Jacob T; Pierre, Philippe; Chadee, Deborah N; Pizza, Francis X

2015-02-15

We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast-myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube-myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube-myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. Copyright © 2014 Elsevier Inc. All rights reserved.

Intercellular Adhesion Molecule-1 Expression by Skeletal Muscle Cells Augments Myogenesis

PubMed Central

Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.; Pierre, Philippe; Chadee, Deborah N.; Pizza, Francis X.

2014-01-01

We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast-myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube-myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube-myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. PMID:25281303

Ultrasound-microbubble-mediated intercellular adhesion molecule-1 small interfering ribonucleic acid transfection attenuates neointimal formation after arterial injury in mice.

PubMed

Suzuki, Jun-ichi; Ogawa, Masahito; Takayama, Kiyoshi; Taniyama, Yoshiaki; Morishita, Ryuichi; Hirata, Yasunobu; Nagai, Ryozo; Isobe, Mitsuaki

2010-03-02

The purpose of this study was to investigate the efficiency of small interfering ribonucleic acid (siRNA) in murine arteries. We transfected it using a nonviral ultrasound-microbubble-mediated in vivo gene delivery system. siRNA is an effective methodology to suppress gene function. The siRNA can be synthesized easily; however, a major obstacle in the use of siRNA as therapeutics is the difficulty involved in effective in vivo delivery. To investigate the efficiency of nonviral ultrasound-microbubble-mediated in vivo siRNA delivery, we used a fluorescein-labeled siRNA, green fluorescent protein (GFP) siRNA, and intercellular adhesion molecule (ICAM)-1 siRNA in murine arteries. Murine femoral arteries were injured using flexible wires to establish arterial injury. The fluorescein-labeled siRNA and GFP siRNA showed that this nonviral approach could deliver siRNA into target arteries effectively without any tissue damage and systemic adverse effects. ICAM-1 siRNA transfection into murine injured arteries significantly suppressed the development of neointimal formation in comparison to those in the control group. Immunohistochemistry revealed that accumulation of T cells and adhesion molecule positive cells was observed in nontreated injured arteries, whereas siRNA suppressed accumulation. The nonviral ultrasound-microbubble delivery of siRNA ensures effective transfection into target arteries. ICAM-1 siRNA has the potential to suppress arterial neointimal formation. Transfection of siRNA can be beneficial for the clinical treatment of cardiovascular and other inflammatory diseases. Copyright 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Nanolayer formation on titanium by phosphonated gelatin for cell adhesion and growth enhancement

PubMed Central

Zhou, Xiaoyue; Park, Shin-Hye; Mao, Hongli; Isoshima, Takashi; Wang, Yi; Ito, Yoshihiro

2015-01-01

Phosphonated gelatin was prepared for surface modification of titanium to stimulate cell functions. The modified gelatin was synthesized by coupling with 3-aminopropylphosphonic acid using water-soluble carbodiimide and characterized by 31P nuclear magnetic resonance and gel permeation chromatography. Circular dichroism revealed no differences in the conformations of unmodified and phosphonated gelatin. However, the gelation temperature was changed by the modification. Even a high concentration of modified gelatin did not form a gel at room temperature. Time-of-flight secondary ion mass spectrometry showed direct bonding between the phosphonated gelatin and the titanium surface after binding. The binding behavior of phosphonated gelatin on the titanium surface was quantitatively analyzed by a quartz crystal microbalance. Ellipsometry showed the formation of a several nanometer layer of gelatin on the surface. Contact angle measurement indicated that the modified titanium surface was hydrophobic. Enhancement of the attachment and spreading of MC-3T3L1 osteoblastic cells was observed on the phosphonated gelatin-modified titanium. These effects on cell adhesion also led to growth enhancement. Phosphonation of gelatin was effective for preparation of a cell-stimulating titanium surface. PMID:26366080

Focused abdominal sonography for trauma (FAST) in blunt paediatric abdominal trauma.

PubMed

Faruque, Ahmad Vaqas; Qazi, Saqib Hamid; Khan, Muhammad Arif Mateen; Akhtar, Wassem; Majeed, Amina

2013-03-01

To evaluate the role of focussed abdominal sonography for trauma in blunt paediatric abdominal trauma patients, and to see if the role of computed tomography scan could be limited to only those cases in which sonography was positive. The retrospective study covered 10 years, from January 1,2000 to December 31,2009, and was conducted at the Department of Radiology and Department of Emergency Medicine, Aga Khan University Hospital, Karachi. It comprised cases of 174 children from birth to 14 years who had presented with blunt abdominal trauma and had focussed abdominal sonography for trauma done at the hospital. The findings were correlated with computed tomography scan of the abdomen and clinical follow-up. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of focussed abdominal sonography for trauma were calculated for blunt abdominal trauma. SPSS 17 was used for statistical analysis. Of the total 174 cases, 31 (17.81%) were later confirmed by abdominal scan. Of these 31 children, sonography had been positive in 29 (93.54%) children. In 21 (67.74%) of the 31 children, sonograpy had been true positive; 8 (25%) (8/31) were false positive; and 2 (6%) (2/31) were false negative. There were 6 (19.3%) children in which sonography was positive and converted to laparotomy. There was no significant difference on account of gender (p>0.356). Focussed abdominal sonography for trauma in the study had sensitivity of 91%, specificity of 95%, positive predictive value of 73%, and negative predictive value of 73% with accuracy of 94%. All patients who had negative sonography were discharged later, and had no complication on clinical follow-up. Focussed abdominal sonography for trauma is a fairly reliable mode to assess blunt abdominal trauma in children. It is a useful tool to pick high-grade solid and hollow viscous injury. The results suggest that the role of computed tomography scan can be limited to those cases in which focussed

Cell adhesion to borate glasses by colloidal probe microscopy.

PubMed

Wiederhorn, Sheldon M; Chae, Young-Hun; Simon, Carl G; Cahn, Jackson; Deng, Yan; Day, Delbert

2011-05-01

The adhesion of osteoblast-like cells to silicate and borate glasses was measured in cell growth medium using colloidal probe microscopy. The probes consisted of silicate and borate glass spheres, 25-50 μm in diameter, attached to atomic force microscope cantilevers. Variables of the study included glass composition and time of contact of the cell to the glasses. Increasing the time of contact from 15 to 900 s increased the force of adhesion. The data could be plotted linearly on a log-log plot of adhesive force versus time. Of the seven glasses tested, five had slopes close to 0.5, suggesting a square root dependence of the adhesive force on the contact time. Such behavior can be interpreted as a diffusion limited process occurring during the early stages of cell attachment. We suggest that the rate limiting step in the adhesion process is the diffusion of integrins resident in the cell membrane to the area of cell attachment. Data presented in this paper support the hypothesis of Hench et al. that strong adhesion depends on the formation of a calcium phosphate reaction layer on the surfaces of the glass. Glasses that did not form a calcium phosphate layer exhibited a weaker adhesive force relative to those glasses that did form a calcium phosphate layer. Published by Elsevier Ltd.

Relationship between water status in dentin and interfacial morphology in all-in-one adhesives.

PubMed

Yoshida, Eiji; Uno, Sigeru; Nodasaka, Yoshinobu; Kaga, Msayuki; Hirano, Susumu

2007-05-01

All-in-one adhesive systems have been recently developed to simplify bonding procedures. The adhesives containing acidic resin monomers generate a relatively thin bonding zone between dentin and composite. This zone may be left acidic and permeable when polymerization is poor. In this study, the effect of water contained in dentin on the quality of the bonding interface was morphologically investigated for all-in-one adhesives. Intact coronal dentin (hydrated dentin), desiccated coronal dentin (dehydrated dentin), caries-affected dentin (CAD) and resin composites were used for adherends to assess the effects of water contained in dentin on the ultra-structures of bonding interfaces created with two all-in-one adhesives and a resin composite. The bonding interfaces were observed under TEM without demineralization. Voids of various sizes were found at the bottom of the adhesive resin layers along the bonding interface of hydrated dentin, while dehydrated dentin, CAD and resin composites did not generate voids. The results showed that the voids were possibly formed by water that had penetrated from the underlying dentin. When the adherend contains little water, the formation of voids will not occur. It was verified that a phenomenon of void formation would not occur in a clinical situation in which caries-affected dentin is mainly subjected to adhesive practices.

Child with Abdominal Pain.

PubMed

Iyer, Rajalakshmi; Nallasamy, Karthi

2018-01-01

Abdominal pain is one of the common symptoms reported by children in urgent care clinics. While most children tend to have self-limiting conditions, the treating pediatrician should watch out for underlying serious causes like intestinal obstruction and perforation peritonitis, which require immediate referral to an emergency department (ED). Abdominal pain may be secondary to surgical or non-surgical causes, and will differ as per the age of the child. The common etiologies for abdominal pain presenting to an urgent care clinic are acute gastro-enteritis, constipation and functional abdominal pain; however, a variety of extra-abdominal conditions may also present as abdominal pain. Meticulous history taking and physical examination are the best tools for diagnosis, while investigations have a limited role in treating benign etiologies.

Peritoneal adhesion prevention with a biodegradable and injectable N,O-carboxymethyl chitosan-aldehyde hyaluronic acid hydrogel in a rat repeated-injury model

NASA Astrophysics Data System (ADS)

Song, Linjiang; Li, Ling; He, Tao; Wang, Ning; Yang, Suleixin; Yang, Xi; Zeng, Yan; Zhang, Wenli; Yang, Li; Wu, Qinjie; Gong, Changyang

2016-11-01

Postoperative peritoneal adhesion is one of the serious issues because it induces severe clinical disorders. In this study, we prepared biodegradable and injectable hydrogel composed of N,O-carboxymethyl chitosan (NOCC) and aldehyde hyaluronic acid (AHA), and assessed its anti-adhesion effect in a rigorous and severe recurrent adhesion model which is closer to clinical conditions. The flexible hydrogel, which gelated in 66 seconds at 37 °C, was cross-linked by the schiff base derived from the amino groups of NOCC and aldehyde groups in AHA. In vitro cytotoxicity test showed the hydrogel was non-toxic. In vitro and in vivo degradation examinations demonstrated the biodegradable and biocompatibility properties of the hydrogel. The hydrogel discs could prevent the invasion of fibroblasts, whereas fibroblasts encapsulated in the porous 3-dimensional hydrogels could grow and proliferate well. Furthermore, the hydrogel was applied to evaluate the anti-adhesion efficacy in a more rigorous recurrent adhesion model. Compared with normal saline group and commercial hyaluronic acid (HA) hydrogel, the NOCC-AHA hydrogel exhibited significant reduction of peritoneal adhesion. Compared to control group, the blood and abdominal lavage level of tPA was increased in NOCC-AHA hydrogel group. These findings suggested that NOCC-AHA hydrogel had a great potential to serve as an anti-adhesion candidate.

A three-phase in-vitro system for studying Pseudomonas aeruginosa adhesion and biofilm formation upon hydrogel contact lenses

PubMed Central

2010-01-01

Background Pseudomonas aeruginosa is commonly associated with contact lens (CL) -related eye infections, for which bacterial adhesion and biofilm formation upon hydrogel CLs is a specific risk factor. Whilst P. aeruginosa has been widely used as a model organism for initial biofilm formation on CLs, in-vitro models that closely reproduce in-vivo conditions have rarely been presented. Results In the current investigation, a novel in-vitro biofilm model for studying the adherence of P. aeruginosa to hydrogel CLs was established. Nutritional and interfacial conditions similar to those in the eye of a CL wearer were created through the involvement of a solid:liquid and a solid:air interface, shear forces and a complex artificial tear fluid. Bioburdens varied depending on the CL material and biofilm maturation occurred after 72 h incubation. Whilst a range of biofilm morphologies were visualised including dispersed and adherent bacterial cells, aggregates and colonies embedded in extracellular polymer substances (EPS), EPS fibres, mushroom-like formations, and crystalline structures, a compact and heterogeneous biofilm morphology predominated on all CL materials. Conclusions In order to better understand the process of biofilm formation on CLs and to test the efficacy of CL care solutions, representative in-vitro biofilm models are required. Here, we present a three-phase biofilm model that simulates the environment in the eye of a CL wearer and thus generates biofilms which resemble those commonly observed in-situ. PMID:21062489

Structural Analysis and Application of n-Alkyl Cyanoacrylate Surgical Adhesives to the Fixation of Meshes for Hernia Repair.

PubMed

Fernández-Gutiérrez, Mar; Rodriguez-Mancheño, Marta; Pérez-Köhler, Bárbara; Pascual, Gemma; Bellón, Juan Manuel; Román, Julio San

2016-12-01

The article deals with a comparative analysis of the parameters of the polymerization in physiological conditions of three commercially available alkyl cyanoacrylates, n-butyl cyanoacrylate (GLUBRAN 2), n-hexyl cyanoacrylate (IFABOND), and n-octyl cyanoacrylate (EVOBOND), the cell behavior of the corresponding polymers and the application of these adhesives in the fixation of surgical polypropylene meshes for hernia repair in an animal model of rabbits. The results obtained demonstrate that the curing process depends on the nature of the alkyl residue of the ester group of cyanoacrylate molecules, being the heat of polymerization lower for the octyl derivative in comparison with the hexyl and butyl, and reaching a maximum temperature of 35 °C after a time of mixing with physiological fluids of 60-70 s. The cell behavior demonstrates that the three systems do not present toxicity for fibroblasts and low adhesion of cells, which is a positive result for application as tissue adhesives, especially for the fixation of abdominal polypropylene meshes for hernia repair. The animal experimentation indicates the excellent tolerance of the meshes fixed with the cyanoacrylic adhesives, during at least a period of 90 d, and guarantees a good adhesion for the application of hernia repair meshes. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Focal adhesion kinase-dependent focal adhesion recruitment of SH2 domains directs SRC into focal adhesions to regulate cell adhesion and migration

PubMed Central

Wu, Jui-Chung; Chen, Yu-Chen; Kuo, Chih-Ting; Wenshin Yu, Helen; Chen, Yin-Quan; Chiou, Arthur; Kuo, Jean-Cheng

2015-01-01

Directed cell migration requires dynamical control of the protein complex within focal adhesions (FAs) and this control is regulated by signaling events involving tyrosine phosphorylation. We screened the SH2 domains present in tyrosine-specific kinases and phosphatases found within FAs, including SRC, SHP1 and SHP2, and examined whether these enzymes transiently target FAs via their SH2 domains. We found that the SRC_SH2 domain and the SHP2_N-SH2 domain are associated with FAs, but only the SRC_SH2 domain is able to be regulated by focal adhesion kinase (FAK). The FAK-dependent association of the SRC_SH2 domain is necessary and sufficient for SRC FA targeting. When the targeting of SRC into FAs is inhibited, there is significant suppression of SRC-mediated phosphorylation of paxillin and FAK; this results in an inhibition of FA formation and maturation and a reduction in cell migration. This study reveals an association between FAs and the SRC_SH2 domain as well as between FAs and the SHP2_N-SH2 domains. This supports the hypothesis that the FAK-regulated SRC_SH2 domain plays an important role in directing SRC into FAs and that this SRC-mediated FA signaling drives cell migration. PMID:26681405

Focal adhesion kinase-dependent focal adhesion recruitment of SH2 domains directs SRC into focal adhesions to regulate cell adhesion and migration.

PubMed

Wu, Jui-Chung; Chen, Yu-Chen; Kuo, Chih-Ting; Wenshin Yu, Helen; Chen, Yin-Quan; Chiou, Arthur; Kuo, Jean-Cheng

2015-12-18

Directed cell migration requires dynamical control of the protein complex within focal adhesions (FAs) and this control is regulated by signaling events involving tyrosine phosphorylation. We screened the SH2 domains present in tyrosine-specific kinases and phosphatases found within FAs, including SRC, SHP1 and SHP2, and examined whether these enzymes transiently target FAs via their SH2 domains. We found that the SRC_SH2 domain and the SHP2_N-SH2 domain are associated with FAs, but only the SRC_SH2 domain is able to be regulated by focal adhesion kinase (FAK). The FAK-dependent association of the SRC_SH2 domain is necessary and sufficient for SRC FA targeting. When the targeting of SRC into FAs is inhibited, there is significant suppression of SRC-mediated phosphorylation of paxillin and FAK; this results in an inhibition of FA formation and maturation and a reduction in cell migration. This study reveals an association between FAs and the SRC_SH2 domain as well as between FAs and the SHP2_N-SH2 domains. This supports the hypothesis that the FAK-regulated SRC_SH2 domain plays an important role in directing SRC into FAs and that this SRC-mediated FA signaling drives cell migration.

Clinical status of ten dentin adhesive systems.

PubMed

Van Meerbeek, B; Peumans, M; Verschueren, M; Gladys, S; Braem, M; Lambrechts, P; Vanherle, G

1994-11-01

Laboratory testing of dentin adhesive systems still requires corroboration by long-term clinical trials for their ultimate clinical effectiveness to be validated. The objective of this clinical investigation was to evaluate, retrospectively, the clinical effectiveness of earlier-investigated dentin adhesive systems (Scotchbond, Gluma, Clearfil New Bond, Scotchbond 2, Tenure, and Tripton), and to compare their clinical results with those obtained with four modern total-etch adhesive systems (Bayer exp. 1 and 2, Clearfil Liner Bond System, and Scotchbond Multi-Purpose). In total, 1177 Class V cervical lesions in the teeth of 346 patients were restored following two cavity designs: In Group A, enamel was neither beveled nor intentionally etched, as per ADA guidelines; in Group B, adjacent enamel was beveled and conditioned. Clinical retention rates definitely indicated the improved clinical efficacy of the newest dentin adhesives over the earlier systems. With regard to adhesion strategy, adhesive systems that removed the smear layer and concurrently demineralized the dentin surface layer performed clinically better than systems that modified the disorderly layer of smear debris without complete removal. Hybridization by resin interdiffusion into the exposed dentinal collagen layer, combined with attachment of resin tags into the opened dentin tubules, appeared to be essential for reliable dentin bonding but might be insufficient by itself. The additional formation of an elastic bonding area as a polymerization shrinkage absorber and the use of a microfine restorative composite apparently guaranteed an efficient clinical result. The perfect one-year retention recorded for Clearfil Liner Bond System and Scotchbond Multi-Purpose must be confirmed at later recalls.

Abdominal wall fat pad biopsy

MedlinePlus

Amyloidosis - abdominal wall fat pad biopsy; Abdominal wall biopsy; Biopsy - abdominal wall fat pad ... most common method of taking an abdominal wall fat pad biopsy . The health care provider cleans the ...

d(−) Lactic Acid-Induced Adhesion of Bovine Neutrophils onto Endothelial Cells Is Dependent on Neutrophils Extracellular Traps Formation and CD11b Expression

PubMed Central

Alarcón, Pablo; Manosalva, Carolina; Conejeros, Ivan; Carretta, María D.; Muñoz-Caro, Tamara; Silva, Liliana M. R.; Taubert, Anja; Hermosilla, Carlos; Hidalgo, María A.; Burgos, Rafael A.

2017-01-01

Bovine ruminal acidosis is of economic importance as it contributes to reduced milk and meat production. This phenomenon is mainly attributed to an overload of highly fermentable carbohydrate, resulting in increased d(−) lactic acid levels in serum and plasma. Ruminal acidosis correlates with elevated acute phase proteins in blood, along with neutrophil activation and infiltration into various tissues leading to laminitis and aseptic polysynovitis. Previous studies in bovine neutrophils indicated that d(−) lactic acid decreased expression of L-selectin and increased expression of CD11b to concentrations higher than 6 mM, suggesting a potential role in neutrophil adhesion onto endothelia. The two aims of this study were to evaluate whether d(−) lactic acid influenced neutrophil and endothelial adhesion and to trigger neutrophil extracellular trap (NET) production (NETosis) in exposed neutrophils. Exposure of bovine neutrophils to 5 mM d(−) lactic acid elevated NET release compared to unstimulated neutrophil negative controls. Moreover, this NET contains CD11b and histone H4 citrullinated, the latter was dependent on PAD4 activation, a critical enzyme in DNA decondensation and NETosis. Furthermore, NET formation was dependent on d(−) lactic acid plasma membrane transport through monocarboxylate transporter 1 (MCT1). d(−) lactic acid enhanced neutrophil adhesion onto endothelial sheets as demonstrated by in vitro neutrophil adhesion assays under continuous physiological flow conditions, indicating that cell adhesion was a NET- and a CD11b/ICAM-1-dependent process. Finally, d(−) lactic acid was demonstrated for the first time to trigger NETosis in a PAD4- and MCT1-dependent manner. Thus, d(−) lactic acid-mediated neutrophil activation may contribute to neutrophil-derived pro-inflammatory processes, such as aseptic laminitis and/or polysynovitis in animals suffering acute ruminal acidosis. PMID:28861083

Adhesive barnacle peptides exhibit a steric-driven design rule to enhance adhesion between asymmetric surfaces.

PubMed

Raman, Sangeetha; Malms, Lukas; Utzig, Thomas; Shrestha, Buddha Ratna; Stock, Philipp; Krishnan, Shankar; Valtiner, Markus

2017-04-01

Barnacles exhibit superior underwater adhesion simply through sequencing of the 21 proteinogenic amino acids, without post processing or using special amino acids. Here, we measure and discuss the molecular interaction of two distinct and recurring short peptide sequences (Bp1 and Bp2) inspired from the surface binding 19kDa protein from the barnacle attachment interface. Using self-assembled monolayer (SAMs) of known physical and chemical properties on molecularly smooth gold substrates in 5mM NaCl at pH 7.3, (1) the adsorption mechanisms of the barnacle inspired peptides are explored using quartz crystal microbalance, and (2) adhesion mediating properties are measured using the surface force apparatus. The hydrophobic Bp1 peptide with a cysteine residue adsorbs irreversibly onto Au surfaces due to thiol bond formation, while on hydrophobic CH 3 SAM surface, the interactions are hydrophobic in nature. Interestingly, Bp2 that contains both hydrophobic and protonated amine units exhibits asymmetric bridging with an exceptionally high adhesion energy up to 100mJ/m 2 between mica and both gold and CH 3 SAM. Surprisingly on hydrophilic surfaces such as COOH- or OH-SAMs both peptides fail to show any interactions, implying the necessity of surface charge to promote bridging. Our results provide insights into the molecular aspects of manipulating and utilizing barnacle-mediated peptides to promote or inhibit underwater adhesion. Copyright © 2016 Elsevier B.V. All rights reserved.

The effect of abdominal pressure on urinary flow rate.

PubMed

Hasegawa, N; Kitagawa, Y; Takasaki, N; Miyazaki, S

1983-07-01

We examined the effect of abdominal pressure on urinary flow rate and urethral closure pressure in 46 subjects, ranging in age from 26 to 82 years. An increase in urinary flow rate caused by abdominal straining was not found when organic obstruction was present in the prostatic urethra in men or the proximal urethra in women, or when dysuria is caused by the lowered detrusor pressure. An increase in urinary flow rate caused by straining was noted when anterior urethral stricture or stress incontinence was present. The increase in urinary flow rate owing to straining was undetermined in the control group. The urethral closure pressure on the anti-stress incontinence zone increased as a result of straining at the same time and to the same degree as did the intravesical pressure. When the anti-stress incontinence zone was subjected to transurethral resection for canal formation urination became possible as a result of straining. The patients who were able to urinate with straining sometimes suffered temporary stress incontinence. The degree of straining did not determine whether the patient could urinate with straining. Therefore, it was concluded that abdominal pressure should be excluded from intravesical pressure in performing several urodynamic studies on the lower urinary tract, such as pressure flow studies, and that it is important to have a sufficient canal formation in the anti-stress incontinence zone when urination with straining is expected when performing an operation on patients with urethral obstruction in the anti-stress incontinence zone.

Evaluation of high temperature structural adhesives for extended service, phase 5

NASA Technical Reports Server (NTRS)

Hendricks, C. L.; Hill, S. G.; Hale, J. N.; Dumars, W. G.

1987-01-01

The evaluation of 3 experimental polymers from NASA-Langley and a commercially produced polymer from Mitsui Toatsu Chemicals as high temperature structural adhesives is presented. A polyphenylquinoxaline (PPQ), polyimide (STPI/LaRC-2), and a polyarylene ether (PAE-SO2) were evaluated as metal-to-metal adhesives. Lap shear, crack extension, and climbing drum peel specimens were fabricated from all three polymers and tested after thermal, combined thermal/humidity, and stressed hydraulic fluid (Skydrol) exposure. The fourth polymer, LARC-TPI was evaluated as an adhesive for titanium honeycomb sandwich structure. All three experimental polymers performed well as metal-to-metal adhesives from 219 K (-65 F) to 505 K (450 F), including humidity exposure. Structural adhesive strength was also maintained at 505 K for a minimum of 3000 hours. LaRC-TPI was evaluated as a high temperature (505 K) adhesive for titanium honeycomb sandwich structure. The LaRC-TPI bonding process development concentrated on improving the honeycomb core-to-skin bond. The most promising approach of those evaluated combined a LaRC-TPI polymer solution with a semi-crystalline LaRC-TPI powder for adhesive film fabrication and fillet formation.

Improved adhesion of Ni films on X-ray damaged polytetrafluoroethylene

NASA Technical Reports Server (NTRS)

Wheeler, D. R.; Pepper, S. V.

1981-01-01

The considered investigation shows that the adhesion of evaporated Ni on polytetrafluoroethylene (PTFE) is enhanced by irradiating the PTFE surface prior to evaporation. Evidence obtained with the aid of X-ray photoelectron spectroscopy is presented concerning the association of the enhanced adhesion with an interfacial chemical reaction. Evaporated Ni clearly adheres better to the X-ray damaged PTFE surface than to the undamaged surface. There is evidence that the improved adhesion is not related to the Ni-C bond, but rather to the NiF2. A possible mechanism which may be consistent with the data is the formation of a F-Ni-C complex, where C is a member of the polymer chain.

The Utility of Diagnostic Laparoscopy in Post-Bariatric Surgery Patients with Chronic Abdominal Pain of Unknown Etiology.

PubMed

Alsulaimy, Mohammad; Punchai, Suriya; Ali, Fouzeyah A; Kroh, Matthew; Schauer, Philip R; Brethauer, Stacy A; Aminian, Ali

2017-08-01

Chronic abdominal pain after bariatric surgery is associated with diagnostic and therapeutic challenges. The aim of this study was to evaluate the yield of laparoscopy as a diagnostic and therapeutic tool in post-bariatric surgery patients with chronic abdominal pain who had negative imaging and endoscopic studies. A retrospective analysis was performed on post-bariatric surgery patients who underwent laparoscopy for diagnosis and treatment of chronic abdominal pain at a single academic center. Only patients with both negative preoperative CT scan and upper endoscopy were included. Total of 35 post-bariatric surgery patients met the inclusion criteria, and all had history of Roux-en-Y gastric bypass. Twenty out of 35 patients (57%) had positive findings on diagnostic laparoscopy including presence of adhesions (n = 12), chronic cholecystitis (n = 4), mesenteric defect (n = 2), internal hernia (n = 1), and necrotic omentum (n = 1). Two patients developed post-operative complications including a pelvic abscess and an abdominal wall abscess. Overall, 15 patients (43%) had symptomatic improvement after laparoscopy; 14 of these patients had positive laparoscopic findings requiring intervention (70% of the patients with positive laparoscopy). Conversely, 20 (57%) patients required long-term medical treatment for management of chronic abdominal pain. Diagnostic laparoscopy, which is a safe procedure, can detect pathological findings in more than half of post-bariatric surgery patients with chronic abdominal pain of unknown etiology. About 40% of patients who undergo diagnostic laparoscopy and 70% of patients with positive findings on laparoscopy experience significant symptom improvement. Patients should be informed that diagnostic laparoscopy is associated with no symptom improvement in about half of cases.

Effect of long-range repulsive Coulomb interactions on packing structure of adhesive particles.

PubMed

Chen, Sheng; Li, Shuiqing; Liu, Wenwei; Makse, Hernán A

2016-02-14

The packing of charged micron-sized particles is investigated using discrete element simulations based on adhesive contact dynamic model. The formation process and the final obtained structures of ballistic packings are studied to show the effect of interparticle Coulomb force. It is found that increasing the charge on particles causes a remarkable decrease of the packing volume fraction ϕ and the average coordination number 〈Z〉, indicating a looser and chainlike structure. Force-scaling analysis shows that the long-range Coulomb interaction changes packing structures through its influence on particle inertia before they are bonded into the force networks. Once contact networks are formed, the expansion effect caused by repulsive Coulomb forces are dominated by short-range adhesion. Based on abundant results from simulations, a dimensionless adhesion parameter Ad*, which combines the effects of the particle inertia, the short-range adhesion and the long-range Coulomb interaction, is proposed and successfully scales the packing results for micron-sized particles within the latest derived adhesive loose packing (ALP) regime. The structural properties of our packings follow well the recent theoretical prediction which is described by an ensemble approach based on a coarse-grained volume function, indicating some kind of universality in the low packing density regime of the phase diagram regardless of adhesion or particle charge. Based on the comprehensive consideration of the complicated inter-particle interactions, our findings provide insight into the roles of short-range adhesion and repulsive Coulomb force during packing formation and should be useful for further design of packings.

Pollenkitt wetting mechanism enables species-specific tunable pollen adhesion.

PubMed

Lin, Haisheng; Gomez, Ismael; Meredith, J Carson

2013-03-05

Plant pollens are microscopic particles exhibiting a remarkable breadth of complex solid surface features. In addition, many pollen grains are coated with a viscous liquid, "pollenkitt", thought to play important roles in pollen dispersion and adhesion. However, there exist no quantitative studies of the effects of solid surface features or pollenkitt on adhesion of pollen grains, and it remains unclear what role these features play in pollen adhesion and transport. We report AFM adhesion measurements of five pollen species with a series of test surfaces in which each pollen has a unique solid surface morphology and pollenkitt volume. The results indicate that the combination of surface morphology (size and shape of echinate or reticulate features) with the pollenkitt volume provides pollens with a remarkably tunable adhesion to surfaces. With pollenkitt removed, pollen grains had relatively low adhesion strengths that were independent of surface chemistry and scalable with the tip radius of the pollen's ornamentation features, according to the Hamaker model. With the pollenkitt intact, adhesion was up to 3-6 times higher than the dry grains and exhibited strong substrate dependence. The adhesion enhancing effect of pollenkitt was driven by the formation of pollenkitt capillary bridges and was surprisingly species-dependent, with echinate insect-pollinated species (dandelion and sunflower) showing significantly stronger adhesion and higher substrate dependence than wind-pollinated species (ragweed, poplar, and olive). The combination of high pollenkitt volume and large convex, spiny surface features in echinate entomophilous varieties appears to enhance the spreading area of the liquid pollenkitt relative to varieties of pollen with less pollenkitt volume and less pronounced surface features. Measurements of pollenkitt surface energy indicate that the adhesive strength of capillary bridges is primarily dependent on nonpolar van der Waals interactions, with some

Theory and simulations of adhesion receptor dimerization on membrane surfaces.

PubMed

Wu, Yinghao; Honig, Barry; Ben-Shaul, Avinoam

2013-03-19

The equilibrium constants of trans and cis dimerization of membrane bound (2D) and freely moving (3D) adhesion receptors are expressed and compared using elementary statistical-thermodynamics. Both processes are mediated by the binding of extracellular subdomains whose range of motion in the 2D environment is reduced upon dimerization, defining a thin reaction shell where dimer formation and dissociation take place. We show that the ratio between the 2D and 3D equilibrium constants can be expressed as a product of individual factors describing, respectively, the spatial ranges of motions of the adhesive domains, and their rotational freedom within the reaction shell. The results predicted by the theory are compared to those obtained from a novel, to our knowledge, dynamical simulations methodology, whereby pairs of receptors perform realistic translational, internal, and rotational motions in 2D and 3D. We use cadherins as our model system. The theory and simulations explain how the strength of cis and trans interactions of adhesive receptors are affected both by their presence in the constrained intermembrane space and by the 2D environment of membrane surfaces. Our work provides fundamental insights as to the mechanism of lateral clustering of adhesion receptors after cell-cell contact and, more generally, to the formation of lateral microclusters of proteins on cell surfaces. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Reversible adhesion switching of porous fibrillar adhesive pads by humidity.

PubMed

Xue, Longjian; Kovalev, Alexander; Dening, Kirstin; Eichler-Volf, Anna; Eickmeier, Henning; Haase, Markus; Enke, Dirk; Steinhart, Martin; Gorb, Stanislav N

2013-01-01

We report reversible adhesion switching on porous fibrillar polystyrene-block-poly(2-vinyl pyridine) (PS-b-P2VP) adhesive pads by humidity changes. Adhesion at a relative humidity of 90% was more than nine times higher than at a relative humidity of 2%. On nonporous fibrillar adhesive pads of the same material, adhesion increased only by a factor of ~3.3. The switching performance remained unchanged in at least 10 successive high/low humidity cycles. Main origin of enhanced adhesion at high humidity is the humidity-induced decrease in the elastic modulus of the polar component P2VP rather than capillary force. The presence of spongelike continuous internal pore systems with walls consisting of P2VP significantly leveraged this effect. Fibrillar adhesive pads on which adhesion is switchable by humidity changes may be used for preconcentration of airborne particulates, pollutants, and germs combined with triggered surface cleaning.

Improved Adhesion and Compliancy of Hierarchical Fibrillar Adhesives.

PubMed

Li, Yasong; Gates, Byron D; Menon, Carlo

2015-08-05

The gecko relies on van der Waals forces to cling onto surfaces with a variety of topography and composition. The hierarchical fibrillar structures on their climbing feet, ranging from mesoscale to nanoscale, are hypothesized to be key elements for the animal to conquer both smooth and rough surfaces. An epoxy-based artificial hierarchical fibrillar adhesive was prepared to study the influence of the hierarchical structures on the properties of a dry adhesive. The presented experiments highlight the advantages of a hierarchical structure despite a reduction of overall density and aspect ratio of nanofibrils. In contrast to an adhesive containing only nanometer-size fibrils, the hierarchical fibrillar adhesives exhibited a higher adhesion force and better compliancy when tested on an identical substrate.

Stress relaxing hyaluronic acid-collagen hydrogels promote cell spreading, fiber remodeling, and focal adhesion formation in 3D cell culture.

PubMed

Lou, Junzhe; Stowers, Ryan; Nam, Sungmin; Xia, Yan; Chaudhuri, Ovijit

2018-02-01

The physical and architectural cues of the extracellular matrix (ECM) play a critical role in regulating important cellular functions such as spreading, migration, proliferation, and differentiation. Natural ECM is a complex viscoelastic scaffold composed of various distinct components that are often organized into a fibrillar microstructure. Hydrogels are frequently used as synthetic ECMs for 3D cell culture, but are typically elastic, due to covalent crosslinking, and non-fibrillar. Recent work has revealed the importance of stress relaxation in viscoelastic hydrogels in regulating biological processes such as spreading and differentiation, but these studies all utilize synthetic ECM hydrogels that are non-fibrillar. Key mechanotransduction events, such as focal adhesion formation, have only been observed in fibrillar networks in 3D culture to date. Here we present an interpenetrating network (IPN) hydrogel system based on HA crosslinked with dynamic covalent bonds and collagen I that captures the viscoelasticity and fibrillarity of ECM in tissues. The IPN hydrogels exhibit two distinct processes in stress relaxation, one from collagen and the other from HA crosslinking dynamics. Stress relaxation in the IPN hydrogels can be tuned by modulating HA crosslinker affinity, molecular weight of the HA, or HA concentration. Faster relaxation in the IPN hydrogels promotes cell spreading, fiber remodeling, and focal adhesion (FA) formation - behaviors often inhibited in other hydrogel-based materials in 3D culture. This study presents a new, broadly adaptable materials platform for mimicking key ECM features of viscoelasticity and fibrillarity in hydrogels for 3D cell culture and sheds light on how these mechanical and structural cues regulate cell behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biofilm formation and binding specificities of CFA/I, CFA/II and CS2 adhesions of enterotoxigenic Escherichia coli and Cfae-R181A mutant.

PubMed

Liaqat, Iram; Sakellaris, Harry

2012-07-01

Enterotoxigenic Escherichia coli (ETEC) strains are leading causes of childhood diarrhea in developing countries. Adhesion is the first step in pathogenesis of ETEC infections and ETEC pili designated colonization factor antigens (CFAs) are believed to be important in the biofim formation, colonization and host cell adhesions. As a first step, we have determined the biofilm capability of ETEC expressing various types of pili (CFA/I, CfaE-R181A mutant/CfaE tip mutant, CFA/II and CS2). Further, enzyme-linked immunosorbent assay (ELISA) assay were developed to compare the binding specificity of CFA/I, CFA/II (CS1 - CS3) and CS2 of ETEC, using extracted pili and piliated bacteria. CFA/II strain (E24377a) as well as extracted pili exhibited significantly higher binding both in biofilm and ELISA assays compared to non piliated wild type E24377a, CFA/I and CS2 strains. This indicates that co-expression of two or more CS2 in same strain is more efficient in increasing adherence. Significant decrease in binding specificity of DH5αF'lacI (q)/∆cotD (CS2) strain and MC4100/pEU2124 (CfaE-R181A) mutant strain indicated the important contribution of tip proteins in adherence assays. However, CS2 tip mutant strain (DH5αF'lacI (q)/pEU5881) showed that this specific residue may not be important as adhesions in these strains. In summary, our data suggest that pili, their minor subunits are important for biofilm formation and adherence mechanisms. Overall, the functional reactivity of strains co expressing various antigens, particularly minor subunit antigen observed in this study suggest that fewer antibodies may be required to elicit immunity to ETEC expressing a wider array of related pili.

Evaluation of adhesive and anti-adhesive properties of Pseudomonas aeruginosa biofilms and their inhibition by herbal plants

PubMed Central

Zameer, Farhan; MS, Rukmangada; Chauhan, Jyoti Bala; Khanum, Shaukath Ara; Kumar, Pramod; Devi, Aishwarya Tripurasundari; MN, Nagendra Prasad; BL, Dhananjaya

2016-01-01

Background and Objectives: Adhesion and colonization are prerequisites for the establishment of bacterial pathogenesis. The biofilm development of Pseudomonas aeruginosa was assessed on adhesive surfaces like dialysis membrane, stainless steel, glass and polystyrene. Materials and Methods: Microtiter plate biofilm assay was performed to assess the effect of nutrient medium and growth parameters of P. aeruginosa. Further, its growth on adhesive surfaces namely hydrophilic (dialysis membrane) and hydrophobic (polystyrene plate, square glass and stainless steel coupon) was assessed. The exopolysaccharide (EPS) was quantified using ruthenium red microplate assay and microscopic analysis was used to observe P. aeruginosa biofilm architecture. The anti-biofilm activity of herbal extracts on mature P. aeruginosa was performed. Results: The formation of large scale biofilms on dialysis membrane for 72 h was proved to be the best surface. In microscopic studies, very few exopolysaccaride fibrils, indicating a rather loose matrix was observed at 48 h. Further, thick exopolysaccaride, indicated higher adhesive properties at 72 h which is evident from ruthenium red staining. Among the plant extract used, Justicia wynaadensis leaf and Aristolochia indica (Eswari) root extract showed significant reduction of anti-biofilm activity of 0.178 OD and 0.192 OD in inhibiting mature biofilms at 0.225 OD respectively, suggesting the possible use of these extracts as efficient anti-adhesive and biofilm-disrupting agents with potential applications in controlling biofilms on surfaces. Conclusion: Our study facilitates better understanding in the development of P. aeruginosa biofilms on different food processing and clinical surfaces ultimately taking care of food safety and hygiene. PMID:27307976

Mechanical and Functional Properties of Nickel Titanium Adhesively Bonded Joints

NASA Astrophysics Data System (ADS)

Niccoli, F.; Alfano, M.; Bruno, L.; Furgiuele, F.; Maletta, C.

2014-07-01

In this study, adhesive joints made up of commercial NiTi sheets with shape memory capabilities are analyzed. Suitable surface pre-treatments, i.e., degreasing, sandblasting, and chemical etching, are preliminary compared in terms of surface roughness, surface energy, and substrate thinning. Results indicate that chemical etching induces marked substrate thinning without substantial gains in terms of surface roughness and free energy. Therefore, adhesive joints with degreased and sandblasted substrates are prepared and tested under both static and cyclic conditions, and damage development within the adhesive layer is monitored in situ using a CCD camera. Sandblasted specimens have a significantly higher mechanical static strength with respect to degreased ones, although they essentially fail in similar fashion, i.e., formation of microcracks followed by decohesion along the adhesive/substrate interface. In addition, the joints show a good functional response with almost complete shape memory recovery after thermo-mechanical cycling, i.e., a small accumulation of residual deformations occurs. The present results show that adhesive bonding is a viable joining technique for NiTi alloys.

Bond strength of different adhesives to normal and caries-affected dentins.

PubMed

Xuan, Wei; Hou, Ben-xiang; Lü, Ya-lin

2010-02-05

Currently, several systems of dentin substrate-reacting adhesives are available for use in the restorative treatment against caries. However, the bond effectiveness and property of different adhesive systems to caries-affected dentin are not fully understood. The objective of this study was to evaluate the bond strength of different adhesives to both normal dentin (ND) and caries-affected dentin (CAD) and to analyze the dentin/adhesive interfacial characteristics. Twenty eight extracted human molars with coronal medium carious lesions were randomly assigned to four groups according to adhesives used. ND and CAD were bonded with etch-and-rinse adhesive Adper Single Bond 2 (SB2) or self-etching adhesives Clearfil SE Bond (CSE), Clearfil S(3) Bond (CS3), iBond GI (IB). Rectangular sticks of resin-dentin bonded interfaces 0.9 mm(2) were obtained. The specimens were subjected to microtensile bond strength (microTBS) testing at a crosshead speed of 1 mm/min. Mean microTBS was statistically analyzed with analysis of variance (ANOVA) and Student-Newman-Keuls tests. Interfacial morphologies were analyzed by Scanning Electron Microscopy (SEM). Etch-and-rinse adhesive Adper(TM) Single Bond 2 yielded high bond strength when applied to both normal and caries-affected dentin. The two-step self-etching adhesive Clearfil SE Bond generated the highest bond strength to ND among all adhesives tested but a significantly reduced strength when applied to CAD. For the one-step self-etching adhesives, Clearfil S(3) Bond and iBond GI, the bond strength was relatively low regardless of the dentin type. SEM interfacial analysis revealed that hybrid layers were thicker with poorer resin tag formation and less resin-filled lateral branches in the CAD than in the ND for all the adhesives tested. The etch-and-rinse adhesive performed more effectively to caries-affected dentin than the self-etching adhesives.

State diagram for adhesion dynamics of deformable capsules under shear flow.

PubMed

Luo, Zheng Yuan; Bai, Bo Feng

2016-08-17

Due to the significance of understanding the underlying mechanisms of cell adhesion in biological processes and cell capture in biomedical applications, we numerically investigate the adhesion dynamics of deformable capsules under shear flow by using a three-dimensional computational fluid dynamic model. This model is based on the coupling of the front tracking-finite element method for elastic mechanics of the capsule membrane and the adhesion kinetics simulation for adhesive interactions between capsules and functionalized surfaces. Using this model, three distinct adhesion dynamic states are predicted, such as detachment, rolling and firm-adhesion. Specifically, the effects of capsule deformability quantified by the capillary number on the transitions of these three dynamic states are investigated by developing an adhesion dynamic state diagram for the first time. At low capillary numbers (e.g. Ca < 0.0075), whole-capsule deformation confers the capsule a flattened bottom in contact with the functionalized surface, which hence promotes the rolling-to-firm-adhesion transition. It is consistent with the observations from previous studies that cell deformation promotes the adhesion of cells lying in the rolling regime. However, it is surprising to find that, at relatively high capillary numbers (e.g. 0.0075 < Ca < 0.0175), the effect of capsule deformability on its adhesion dynamics is far more complex than just promoting adhesion. High deformability of capsules makes their bottom take a concave shape with no adhesion bond formation in the middle. The appearance of this specific capsule shape inhibits the transitions of both rolling-to-firm-adhesion and detachment-to-rolling, and it means that capsule deformation no longer promotes the capsule adhesion. Besides, it is interesting to note that, when the capillary number exceeds a critical value (e.g. Ca = 0.0175), the rolling state no longer appears, since capsules exhibit large deviation from the spherical shape.

Abdominal ectopic pregnancy after in vitro fertilization and single embryo transfer: a case report and systematic review.

PubMed

Yoder, Nicole; Tal, Reshef; Martin, J Ryan

2016-10-19

Ectopic pregnancy is the leading cause of maternal morbidity and mortality during the first trimester and the incidence increases dramatically with assisted-reproductive technology (ART), occurring in approximately 1.5-2.1 % of patients undergoing in-vitro fertilization (IVF). Abdominal ectopic pregnancy is a rare yet clinically significant form of ectopic pregnancy due to potentially high maternal morbidity. While risk factors for ectopic pregnancy after IVF have been studied, very little is known about risk factors specific for abdominal ectopic pregnancy. We present a case of a 30 year-old woman who had an abdominal ectopic pregnancy following IVF and elective single embryo transfer, which was diagnosed and managed by laparoscopy. We performed a systematic literature search to identify case reports of abdominal or heterotopic abdominal ectopic pregnancies after IVF. A total of 28 cases were identified. Patients' ages ranged from 23 to 38 (Mean 33.2, S.D. = 3.2). Infertility causes included tubal factor (46 %), endometriosis (14 %), male factor (14 %), pelvic adhesive disease (7 %), structural/DES exposure (7 %), and unexplained infertility (14 %). A history of ectopic pregnancy was identified in 39 % of cases. A history of tubal surgery was identified in 50 % of cases, 32 % cases having had bilateral salpingectomy. Transfer of two embryos or more (79 %) and fresh embryo transfer (71 %) were reported in the majority of cases. Heterotopic abdominal pregnancy occurred in 46 % of cases while 54 % were abdominal ectopic pregnancies. Our systematic review has revealed several trends in reported cases of abdominal ectopic pregnancy after IVF including tubal factor infertility, history of tubal ectopic and tubal surgery, higher number of embryos transferred, and fresh embryo transfers. These are consistent with known risk factors for ectopic pregnancy following IVF. Further research focusing on more homogenous population may help in better characterizing

Heterofunctional nanosheet controlling cell adhesion properties by collagen coating.

PubMed

Niwa, Daisuke; Fujie, Toshinori; Lang, Thorsten; Goda, Nobuhito; Takeoka, Shinji

2012-08-01

Recently, biomaterials have been widely used in a variety of medical applications. We previously reported that a poly-l-lactic acid (PLLA) nanosheet shows anti-adhesive properties and constitutes a useful biomaterial for preventing unwanted wound adhesion in surgical operations. In this article, we examine whether the PLLA nanosheet can be specifically modified with biomacromolecules on one surface only. Such an approach would endow each side of the nanosheet with discrete functions, that is anti-adhesive and pro-healing properties. We fabricated two distinct PLLA nanosheets: (i) collagen cast on the surface of a PLLA nanosheet (Col-Cast-PLLA) and (ii) collagen spin-coated on the nanosheet (Col-Spin-PLLA). In the Col-Spin-PLLA nanosheet, the collagen layer had a thickness of 5-10 nm on the PLLA surface and displayed increased hydrophilicity compared to both PLLA and Col-Cast-PLLA nanosheets. In addition, atomic force microscopy showed disorganized collagen fibril formation on the PLLA layer when covered using the spin-coating method, while apparent bundle formations of collagen were formed in the Col-Cast-PLLA nanosheet. The Col-Spin-PLLA nanosheet provided a microenvironment for cells to adhere and spread. By contrast, the Col-Cast-PLLA nanosheet displayed reduced cell adhesion compared to the Col-Spin-PLLA nanosheet. Consistent with these findings, immunocytochemical analysis clearly showed fine networks of actin filaments in cells cultured on the Col-Spin-PLLA, but not the Col-Cast-PLLA nanosheet. Therefore, the Col-Spin-PLLA nanosheet was shown to be more suitable for acting as a scaffold. In conclusion, we have succeeded in developing a heterofunctional nanosheet comprising a collagen modified side, which has the ability to rapidly adhere cells, and an unmodified side, which acts as an adhesion barrier, by using a spin-coating technique.

Don't Forget the Abdominal Wall: Imaging Spectrum of Abdominal Wall Injuries after Nonpenetrating Trauma.

PubMed

Matalon, Shanna A; Askari, Reza; Gates, Jonathan D; Patel, Ketan; Sodickson, Aaron D; Khurana, Bharti

2017-01-01

Abdominal wall injuries occur in nearly one of 10 patients coming to the emergency department after nonpenetrating trauma. Injuries range from minor, such as abdominal wall contusion, to severe, such as abdominal wall rupture with evisceration of abdominal contents. Examples of specific injuries that can be detected at cross-sectional imaging include abdominal muscle strain, tear, or hematoma, including rectus sheath hematoma (RSH); traumatic abdominal wall hernia (TAWH); and Morel-Lavallée lesion (MLL) (closed degloving injury). These injuries are often overlooked clinically because of (a) a lack of findings at physical examination or (b) distraction by more-severe associated injuries. However, these injuries are important to detect because they are highly associated with potentially grave visceral and vascular injuries, such as aortic injury, and because their detection can lead to the diagnosis of these more clinically important grave traumatic injuries. Failure to make a timely diagnosis can result in delayed complications, such as bowel hernia with potential for obstruction or strangulation, or misdiagnosis of an abdominal wall neoplasm. Groin injuries, such as athletic pubalgia, and inferior costochondral injuries should also be considered in patients with abdominal pain after nonpenetrating trauma, because these conditions may manifest with referred abdominal pain and are often included within the field of view at cross-sectional abdominal imaging. Radiologists must recognize and report acute abdominal wall injuries and their associated intra-abdominal pathologic conditions to allow appropriate and timely treatment. © RSNA, 2017.

Correlation between intra-abdominal pressure and pulmonary volumes after superior and inferior abdominal surgery.

PubMed

Cleva, Roberto de; Assumpção, Marianna Siqueira de; Sasaya, Flavia; Chaves, Natalia Zuniaga; Santo, Marco Aurelio; Fló, Claudia; Lunardi, Adriana C; Jacob Filho, Wilson

2014-07-01

Patients undergoing abdominal surgery are at risk for pulmonary complications. The principal cause of postoperative pulmonary complications is a significant reduction in pulmonary volumes (FEV1 and FVC) to approximately 65-70% of the predicted value. Another frequent occurrence after abdominal surgery is increased intra-abdominal pressure. The aim of this study was to correlate changes in pulmonary volumes with the values of intra-abdominal pressure after abdominal surgery, according to the surgical incision in the abdomen (superior or inferior). We prospectively evaluated 60 patients who underwent elective open abdominal surgery with a surgical time greater than 240 minutes. Patients were evaluated before surgery and on the 3rd postoperative day. Spirometry was assessed by maximal respiratory maneuvers and flow-volume curves. Intra-abdominal pressure was measured in the postoperative period using the bladder technique. The mean age of the patients was 56 ± 13 years, and 41.6% 25 were female; 50 patients (83.3%) had malignant disease. The patients were divided into two groups according to the surgical incision (superior or inferior). The lung volumes in the preoperative period showed no abnormalities. After surgery, there was a significant reduction in both FEV1 (1.6 ± 0.6 L) and FVC (2.0 ± 0.7 L) with maintenance of FEV1/FVC of 0.8 ± 0.2 in both groups. The maximum intra-abdominal pressure values were similar (p=0.59) for the two groups. There was no association between pulmonary volumes and intra-abdominal pressure measured in any of the groups analyzed. Our results show that superior and inferior abdominal surgery determines hypoventilation, unrelated to increased intra-abdominal pressure. Patients at high risk of pulmonary complications should receive respiratory care even if undergoing inferior abdominal surgery.

Prevention of peritendinous adhesions with electrospun ibuprofen-loaded poly(L-lactic acid)-polyethylene glycol fibrous membranes.

PubMed

Liu, Shen; Hu, Changmin; Li, Fengfeng; Li, Xu-jun; Cui, Wenguo; Fan, Cunyi

2013-02-01

Physical barriers are commonly used to reduce peritendinous adhesion after injury. However, the inflammatory response to surgery cannot be prevented. This study was designed to evaluate the ability of ibuprofen-loaded poly(l-lactic acid)-polyethylene glycol (PELA) diblock copolymer fibrous membranes in preventing adhesion formation and reduce inflammation. Electrospun PELA fibrous membranes underwent mechanical testing and were characterized by morphology, surface wettability, drug release, and degradation. Results of an in vitro drug release study showed that a burst release was followed by sustained release from fibrous membranes with high initial ibuprofen content. Fewer L929 mouse fibroblasts adhered to and proliferated on the ibuprofen-loaded PELA fibrous membrane compared with tissue culture plates or PELA fibrous membrane without ibuprofen. In a chicken model of flexor digitorum profundus tendon surgery, the ibuprofen-loaded PELA fibrous membranes prevented tissue adhesion and significantly reduced inflammation. Taken together, these results demonstrate that ibuprofen-loaded PELA fibrous membranes prevent peritendinous adhesion formation better than membranes that do not contain ibuprofen, through anti-adhesion and anti-inflammatory actions.

Bio-active molecules modified surfaces enhanced mesenchymal stem cell adhesion and proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mobasseri, Rezvan; Center for Nanofibers & Nanotechnology, Department of Mechanical Engineering, National University of Singapore, 117576; Tian, Lingling

Surface modification of the substrate as a component of in vitro cell culture and tissue engineering, using bio-active molecules including extracellular matrix (ECM) proteins or peptides derived ECM proteins can modulate the surface properties and thereby induce the desired signaling pathways in cells. The aim of this study was to evaluate the behavior of human bone marrow mesenchymal stem cells (hBM-MSCs) on glass substrates modified with fibronectin (Fn), collagen (Coll), RGD peptides (RGD) and designed peptide (R-pept) as bio-active molecules. The glass coverslips were coated with fibronectin, collagen, RGD peptide and R-peptide. Bone marrow mesenchymal stem cells were cultured on differentmore » substrates and the adhesion behavior in early incubation times was investigated using scanning electron microscopy (SEM) and confocal microscopy. The MTT assay was performed to evaluate the effect of different bio-active molecules on MSCs proliferation rate during 24 and 72 h. Formation of filopodia and focal adhesion (FA) complexes, two steps of cell adhesion process, were observed in MSCs cultured on bio-active molecules modified coverslips, specifically in Fn coated and R-pept coated groups. SEM image showed well adhesion pattern for MSCs cultured on Fn and R-pept after 2 h incubation, while the shape of cells cultured on Coll and RGD substrates indicated that they might experience stress condition in early hours of culture. Investigation of adhesion behavior, as well as proliferation pattern, suggests R-peptide as a promising bio-active molecule to be used for surface modification of substrate in supporting and inducing cell adhesion and proliferation. - Highlights: • Bioactive molecules modified surface is a strategy to design biomimicry scaffold. • Bi-functional Tat-derived peptide (R-pept) enhanced MSCs adhesion and proliferation. • R-pept showed similar influences to fibronectin on FA formation and attachment.« less

Thermal Characterization of Adhesive

NASA Technical Reports Server (NTRS)

Spomer, Ken A.

1999-01-01

The current Space Shuttle Reusable Solid Rocket Motor (RSRM) nozzle adhesive bond system is being replaced due to obsolescence. Down-selection and performance testing of the structural adhesives resulted in the selection of two candidate replacement adhesives, Resin Technology Group's Tiga 321 and 3M's EC2615XLW. This paper describes rocket motor testing of these two adhesives. Four forty-pound charge motors were fabricated in configurations that would allow side by side comparison testing of the candidate replacement adhesives and the current RSRM adhesives. The motors provided an environment where the thermal performance of adhesives in flame surface bondlines was compared. Results of the FPC testing show that: 1) The phenolic char depths on radial bond lines is approximately the same and vary depending on the position in the blast tube regardless of which adhesive was used; 2) The adhesive char depth of the candidate replacement adhesives is less than the char depth of the current adhesives; 3) The heat-affected depth of the candidate replacement adhesives is less than the heat-affected depth of the current adhesives; and 4) The ablation rates for both replacement adhesives are slower than that of the current adhesives.

Adhesive Bioactive Coatings Inspired by Sea Life.

PubMed

Rego, Sónia J; Vale, Ana C; Luz, Gisela M; Mano, João F; Alves, Natália M

2016-01-19

Inspired by nature, in particular by the marine mussels adhesive proteins (MAPs) and by the tough brick-and-mortar nacre-like structure, novel multilayered films are prepared in the present work. Organic-inorganic multilayered films, with an architecture similar to nacre based on bioactive glass nanoparticles (BG), chitosan, and hyaluronic acid modified with catechol groups, which are the main components responsible for the outstanding adhesion in MAPs, are developed for the first time. The biomimetic conjugate is prepared by carbodiimide chemistry and analyzed by ultraviolet-visible spectrophotometry. The buildup of the multilayered films is monitored with a quartz crystal microbalance with dissipation monitoring, and their topography is characterized by atomic force microscopy. The mechanical properties reveal that the films containing catechol groups and BG present an enhanced adhesion. Moreover, the bioactivity of the films upon immersion in a simulated body fluid solution is evaluated by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. It was found that the constructed films promote the formation of bonelike apatite in vitro. Such multifunctional mussel inspired LbL films, which combine enhanced adhesion and bioactivity, could be potentially used as coatings of a variety of implants for orthopedic applications.

Microbial adhesion to silicone hydrogel lenses: a review.

PubMed

Willcox, Mark D P

2013-01-01

Microbial adhesion to contact lenses is believed to be one of the initiating events in the formation of many corneal infiltrative events, including microbial keratitis, that occur during contact lens wear. The advent of silicone hydrogel lenses has not reduced the incidence of these events. This may partly be related to the ability of microbes to adhere to these lenses. The aim of this study was to review the published literature on microbial adhesion to contact lenses, focusing on adhesion to silicone hydrogel lenses. The literature on microbial adhesion to contact lenses was searched, along with associated literature on adverse events that occur during contact lens wear. Particular reference was paid to the years 1995 through 2012 because this encompasses the time when the first clinical trials of silicone hydrogel lenses were reported, and their commercial availability and the publication of epidemiology studies on adverse events were studied. In vitro studies of bacterial adhesion to unworn silicone hydrogel lens have shown that generally, bacteria adhere to these lenses in greater numbers than to the hydroxyethyl methacrylate-based soft lenses. Lens wear has different effects on microbial adhesion, and this is dependent on the type of lens and microbial species/genera that is studied. Biofilms that can be formed on any lens type tend to protect the bacteria and fungi from the effects on disinfectants. Fungal hyphae can penetrate the surface of most types of lenses. Acanthamoeba adhere in greater numbers to first-generation silicone hydrogel lenses compared with the second-generation or hydroxyethyl methacrylate-based soft lenses. Microbial adhesion to silicone hydrogel lenses occurs and is associated with the production of corneal infiltrative events during lens wear.

Bacterial Adhesion to Hexadecane (Model NAPL)-Water Interfaces

NASA Astrophysics Data System (ADS)

Ghoshal, S.; Zoueki, C. R.; Tufenkji, N.

2009-05-01

The rates of biodegradation of NAPLs have been shown to be influenced by the adhesion of hydrocarbon- degrading microorganisms as well as their proximity to the NAPL-water interface. Several studies provide evidence for bacterial adhesion or biofilm formation at alkane- or crude oil-water interfaces, but there is a significant knowledge gap in our understanding of the processes that influence initial adhesion of bacteria on to NAPL-water interfaces. In this study bacterial adhesion to hexadecane, and a series of NAPLs comprised of hexadecane amended with toluene, and/or with asphaltenes and resins, which are the surface active fractions of crude oils, were examined using a Microbial Adhesion to Hydrocarbons (MATH) assay. The microorganisms employed were Mycobacterium kubicae, Pseudomonas aeruginosa and Pseudomonas putida, which are hydrocarbon degraders or soil microorganisms. MATH assays as well as electrophoretic mobility measurements of the bacterial cells and the NAPL droplet surfaces in aqueous solutions were conducted at three solution pHs (4, 6 and 7). Asphaltenes and resins were shown to generally decrease microbial adhesion. Results of the MATH assay were not in qualitative agreement with theoretical predictions of bacteria- hydrocarbon interactions based on the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) model of free energy of interaction between the cell and NAPL droplets. In this model the free energy of interaction between two colloidal particles is predicted based on electrical double layer, van der Waals and hydrophobic forces. It is likely that the steric repulsion between bacteria and NAPL surfaces, caused by biopolymers on bacterial surfaces and aphaltenes and resins at the NAPL-water interface contributed to the decreased adhesion compared to that predicted by the XDLVO model.

Emerging Roles of BAI Adhesion-GPCRs in Synapse Development and Plasticity.

PubMed

Duman, Joseph G; Tu, Yen-Kuei; Tolias, Kimberley F

2016-01-01

Synapses mediate communication between neurons and enable the brain to change in response to experience, which is essential for learning and memory. The sites of most excitatory synapses in the brain, dendritic spines, undergo rapid remodeling that is important for neural circuit formation and synaptic plasticity. Abnormalities in synapse and spine formation and plasticity are associated with a broad range of brain disorders, including intellectual disabilities, autism spectrum disorders (ASD), and schizophrenia. Thus, elucidating the mechanisms that regulate these neuronal processes is critical for understanding brain function and disease. The brain-specific angiogenesis inhibitor (BAI) subfamily of adhesion G-protein-coupled receptors (adhesion-GPCRs) has recently emerged as central regulators of synapse development and plasticity. In this review, we will summarize the current knowledge regarding the roles of BAIs at synapses, highlighting their regulation, downstream signaling, and physiological functions, while noting the roles of other adhesion-GPCRs at synapses. We will also discuss the relevance of BAIs in various neurological and psychiatric disorders and consider their potential importance as pharmacological targets in the treatment of these diseases.

Universal adhesives: the next evolution in adhesive dentistry?

PubMed

Alex, Gary

2015-01-01

Every so often a new material, technique, or technological breakthrough spurs a paradigm shift in the way dentistry is practiced. The development and evolution of reliable enamel and dentin bonding agents is one such example. Indeed, the so-called "cosmetic revolution" in dentistry blossomed in large part due to dramatic advances in adhesive technology. It is the ability to bond various materials in a reasonably predictable fashion to both enamel and dentin substrates that enables dentists to routinely place porcelain veneers, direct and indirect composites, and a plethora of other restorative and esthetic materials. In fact, the longevity and predictability of many (if not most) current restorative procedures is wholly predicated on the dentist's ability to bond various materials to tooth tissues. Adhesive systems have progressed from the largely ineffective systems of the 1970s and early 1980s to the relatively successful total- and self-etching systems of today. The latest players in the adhesive marketplace are the so-called "universal adhesives." In theory, these systems have the potential to significantly simplify and expedite adhesive protocols and may indeed represent the next evolution in adhesive dentistry. But what defines a universal system, and are all these new systems truly "universal" and everything they are claimed to be? This article will examine the origin, chemistry, strengths, weaknesses, and clinical relevance of this new genre of dental adhesives.

Juvenile granulosa cell tumor arising from intra-abdominal testis in newborn: case report and review of the literature.

PubMed

Partalis, Nikolaos; Tzardi, Maria; Barbagadakis, Sophia; Sakellaris, George

2012-05-01

In the present case, the neonate presented with a left-sided abdominal mass and an empty left scrotum. Abdominal ultrasonography showed well-defined cystic formation, and laparotomy revealed a tumor arising from an intra-abdominal left testis. The carcinoembryonic antigen and neuron-specific enolase levels were within normal limits, and the serum β-human chorionic gonadotropin and α-fetoprotein levels were within age-related normal values. The findings from the immunochemistry tests confirmed the diagnosis. Copyright © 2012 Elsevier Inc. All rights reserved.

Lidocaine/ketorolac-loaded biodegradable nanofibrous anti-adhesive membranes that offer sustained pain relief for surgical wounds.

PubMed

Kao, Ching-Wei; Lee, Demei; Wu, Min-Hsuan; Chen, Jan-Kan; He, Hong-Lin; Liu, Shih-Jung

2017-01-01

The aim of this study was to develop and evaluate the effectiveness of biodegradable nanofibrous lidocaine/ketorolac-loaded anti-adhesion membranes to sustainably release analgesics on abdominal surgical wounds. The analgesic-eluting membranes with two polymer-to-drug ratios (6:1 and 4:1) were produced via an electrospinning technique. A high-performance liquid chromatography (HPLC) assay was employed to characterize the in vivo and in vitro release behaviors of the pharmaceuticals from the membranes. It was found that all biodegradable anti-adhesion nanofibers released effective concentrations of lidocaine and ketorolac for over 20 days post surgery. In addition, a transverse laparotomy was setup in a rat model for an in vivo assessment of activity of postoperative recovery. No tissue adhesion was observed at 2 weeks post surgery, demonstrating the potential anti-adhesion capability of the drug-eluting nanofibrous membrane. The postoperative activities were recorded for two groups of rats as follows: rats that did not have any membrane implanted (group A) and rats that had the analgesic-eluting membrane implanted (group B). Rats in group B exhibited faster recovery times than those in group A with regard to postoperative activities, confirming the pain relief effectiveness of the lidocaine- and ketorolac-loaded nanofibrous membranes. The experimental results suggested that the anti-adhesion nanofibrous membranes with sustainable elution of lidocaine and ketorolac are adequately effective and durable for the purposes of postoperative pain relief in rats.

Lidocaine/ketorolac-loaded biodegradable nanofibrous anti-adhesive membranes that offer sustained pain relief for surgical wounds

PubMed Central

Kao, Ching-Wei; Lee, Demei; Wu, Min-Hsuan; Chen, Jan-Kan; He, Hong-Lin; Liu, Shih-Jung

2017-01-01

The aim of this study was to develop and evaluate the effectiveness of biodegradable nanofibrous lidocaine/ketorolac-loaded anti-adhesion membranes to sustainably release analgesics on abdominal surgical wounds. The analgesic-eluting membranes with two polymer-to-drug ratios (6:1 and 4:1) were produced via an electrospinning technique. A high-performance liquid chromatography (HPLC) assay was employed to characterize the in vivo and in vitro release behaviors of the pharmaceuticals from the membranes. It was found that all biodegradable anti-adhesion nanofibers released effective concentrations of lidocaine and ketorolac for over 20 days post surgery. In addition, a transverse laparotomy was setup in a rat model for an in vivo assessment of activity of postoperative recovery. No tissue adhesion was observed at 2 weeks post surgery, demonstrating the potential anti-adhesion capability of the drug-eluting nanofibrous membrane. The postoperative activities were recorded for two groups of rats as follows: rats that did not have any membrane implanted (group A) and rats that had the analgesic-eluting membrane implanted (group B). Rats in group B exhibited faster recovery times than those in group A with regard to postoperative activities, confirming the pain relief effectiveness of the lidocaine- and ketorolac-loaded nanofibrous membranes. The experimental results suggested that the anti-adhesion nanofibrous membranes with sustainable elution of lidocaine and ketorolac are adequately effective and durable for the purposes of postoperative pain relief in rats. PMID:28860755

Effects on in vitro and in vivo angiogenesis induced by small peptides carrying adhesion sequences.

PubMed

Conconi, Maria Teresa; Ghezzo, Francesca; Dettin, Monica; Urbani, Luca; Grandi, Claudio; Guidolin, Diego; Nico, Beatrice; Di Bello, Carlo; Ribatti, Domenico; Parnigotto, Pier Paolo

2010-07-01

It is well known that tumor growth is strictly dependent on neo-vessel formation inside the tumor mass and that cell adhesion is required to allow EC proliferation and migration inside the tumor. In this work, we have evaluated the in vitro and in vivo effects on angiogenesis of some peptides, originally designed to promote cell adhesion on biomaterials, containing RGD motif mediating cell adhesion via integrin receptors [RGD, GRGDSPK, and (GRGDSP)(4)K] or the heparin-binding sequence of human vitronectin that interacts with HSPGs [HVP(351-359)]. Cell adhesion, proliferation, migration, and capillary-like tube formation in Matrigel were determined on HUVECs, whereas the effects on in vivo angiogenesis were evaluated using the CAM assay. (GRGDSP)(4)K linear sequence inhibited cell adhesion, decreased cell proliferation, migration and morphogenesis in Matrigel, and induced anti-angiogenic responses on CAM at higher degree than that determined after incubation with RGD or GRGDSPK. Moreover, it counteracted both in vitro and in vivo the pro-angiogenic effects induced by the Fibroblast growth factor (FGF-2). On the other hand, HVP was not able to affect cell adhesion and appeared less effective than (GRGDSP)(4)K. Our data indicate that the activity of RGD-containing peptides is related to their adhesive properties, and their effects are modulated by the number of cell adhesion motifs and the aminoacidic residues next to these sequences. The anti-angiogenic properties of (GRGDSP)(4)K seem to depend on its interaction with integrins, whereas the effects of HVP may be partially due to an impairment of HSPGs/FGF-2.

Chronic Abdominal Wall Pain.

PubMed

Koop, Herbert; Koprdova, Simona; Schürmann, Christine

2016-01-29

Chronic abdominal wall pain is a poorly recognized clinical problem despite being an important element in the differential diagnosis of abdominal pain. This review is based on pertinent articles that were retrieved by a selective search in PubMed and EMBASE employing the terms "abdominal wall pain" and "cutaneous nerve entrapment syndrome," as well as on the authors' clinical experience. In 2% to 3% of patients with chronic abdominal pain, the pain arises from the abdominal wall; in patients with previously diagnosed chronic abdominal pain who have no demonstrable pathological abnormality, this likelihood can rise as high as 30% . There have only been a small number of clinical trials of treatment for this condition. The diagnosis is made on clinical grounds, with the aid of Carnett's test. The characteristic clinical feature is strictly localized pain in the anterior abdominal wall, which is often mischaracterized as a "functional" complaint. In one study, injection of local anesthesia combined with steroids into the painful area was found to relieve pain for 4 weeks in 95% of patients. The injection of lidocaine alone brought about improvement in 83-91% of patients. Long-term pain relief ensued after a single lidocaine injection in 20-30% of patients, after repeated injections in 40-50% , and after combined lidocaine and steroid injections in up to 80% . Pain that persists despite these treatments can be treated with surgery (neurectomy). Chronic abdominal wall pain is easily diagnosed on physical examination and can often be rapidly treated. Any physician treating patients with abdominal pain should be aware of this condition. Further comparative treatment trials will be needed before a validated treatment algorithm can be established.

The ancillary protein 1 of Streptococcus pyogenes FCT-1 pili mediates cell adhesion and biofilm formation through heterophilic as well as homophilic interactions

PubMed Central

Becherelli, Marco; Manetti, Andrea G O; Buccato, Scilla; Viciani, Elisa; Ciucchi, Laura; Mollica, Giulia; Grandi, Guido; Margarit, Imma

2012-01-01

Summary Gram-positive pili are known to play a role in bacterial adhesion to epithelial cells and in the formation of biofilm microbial communities. In the present study we undertook the functional characterization of the pilus ancillary protein 1 (AP1_M6) from Streptococcus pyogenes isolates expressing the FCT-1 pilus variant, known to be strong biofilm formers. Cell binding and biofilm formation assays using S. pyogenes in-frame deletion mutants, Lactococcus expressing heterologous FCT-1 pili and purified recombinant AP1_M6, indicated that this pilin is a strong cell adhesin that is also involved in bacterial biofilm formation. Moreover, we show that AP1_M6 establishes homophilic interactions that mediate inter-bacterial contact, possibly promoting bacterial colonization of target epithelial cells in the form of three-dimensional microcolonies. Finally, AP1_M6 knockout mutants were less virulent in mice, indicating that this protein is also implicated in GAS systemic infection. PMID:22320452

Peritoneal adhesion prevention with a biodegradable and injectable N,O-carboxymethyl chitosan-aldehyde hyaluronic acid hydrogel in a rat repeated-injury model

PubMed Central

Song, Linjiang; Li, Ling; He, Tao; Wang, Ning; Yang, Suleixin; Yang, Xi; Zeng, Yan; Zhang, Wenli; Yang, Li; Wu, Qinjie; Gong, Changyang

2016-01-01

Postoperative peritoneal adhesion is one of the serious issues because it induces severe clinical disorders. In this study, we prepared biodegradable and injectable hydrogel composed of N,O-carboxymethyl chitosan (NOCC) and aldehyde hyaluronic acid (AHA), and assessed its anti-adhesion effect in a rigorous and severe recurrent adhesion model which is closer to clinical conditions. The flexible hydrogel, which gelated in 66 seconds at 37 °C, was cross-linked by the schiff base derived from the amino groups of NOCC and aldehyde groups in AHA. In vitro cytotoxicity test showed the hydrogel was non-toxic. In vitro and in vivo degradation examinations demonstrated the biodegradable and biocompatibility properties of the hydrogel. The hydrogel discs could prevent the invasion of fibroblasts, whereas fibroblasts encapsulated in the porous 3-dimensional hydrogels could grow and proliferate well. Furthermore, the hydrogel was applied to evaluate the anti-adhesion efficacy in a more rigorous recurrent adhesion model. Compared with normal saline group and commercial hyaluronic acid (HA) hydrogel, the NOCC-AHA hydrogel exhibited significant reduction of peritoneal adhesion. Compared to control group, the blood and abdominal lavage level of tPA was increased in NOCC-AHA hydrogel group. These findings suggested that NOCC-AHA hydrogel had a great potential to serve as an anti-adhesion candidate. PMID:27869192

Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.

We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast–myoblast adhesion, myotube formation,more » myonuclear number, myotube alignment, myotube–myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube–myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. - Highlights: • We examined mechanisms through which skeletal muscle cell expression of ICAM-1 facilitates events of in vitro myogenesis. • Expression of ICAM-1 by cultured myoblasts did not influence their ability to proliferate or differentiate. • Skeletal muscle cell expression of ICAM-1 augmented myoblast fusion, myotube alignment, myotube–myotube fusion, and myotube size. • ICAM-1 augmented myogenic processes

Controlled Delivery of a Focal Adhesion Kinase Inhibitor Results in Accelerated Wound Closure with Decreased Scar Formation.

PubMed

Ma, Kun; Kwon, Sun Hyung; Padmanabhan, Jagannath; Duscher, Dominik; Trotsyuk, Artem A; Dong, Yixiao; Inayathullah, Mohammed; Rajadas, Jayakumar; Gurtner, Geoffrey C

2018-05-15

Formation of scars following wounding or trauma represents a significant healthcare burden costing the economy billions of dollars every year. Activation of focal adhesion kinase (FAK) has been shown to play a pivotal role in transducing mechanical signals to elicit fibrotic responses and scar formation during wound repair. We have previously shown that inhibition of FAK using local injections of a small molecule FAK inhibitor (FAKI) can attenuate scar development in a hypertrophic scar model. Clinical translation of FAKI therapy has been challenging, however, due to the lack of an effective drug delivery system for extensive burn injuries, blast injuries, and large excisional injuries. To address this issue, we have developed a pullulan collagen-based hydrogel to deliver FAKI to excisional and burn wounds in mice. Specifically, two distinct drug-laden hydrogels were developed for rapid or sustained release of FAKI for treatment of burn wounds and excisional wounds, respectively. Controlled delivery of FAKI via pullulan collagen hydrogels accelerated wound healing, reduced collagen deposition and activation of scar forming myofibroblasts in both wound healing models. Our study highlights a biomaterial-based drug delivery approach for wound and scar management that has significant translational implications. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Adhesion of Photoactive Microalgae to Surfaces is Switchable by Light

NASA Astrophysics Data System (ADS)

Bäumchen, Oliver; Kreis, Christian; Le Blay, Marine; Linne, Christine; Makowski, Marcin

The natural habitats of many microorganisms are confined geometries, such as the interstitial space of rocks and soil, where interactions with interfaces and surfaces are of paramount importance. We performed in vivo force spectroscopy experiments on the unicellular biflagellated microalga Chlamydomonas, a prime model organism in cell- and microbiology, and discovered that the flagella-mediated adhesion to surfaces can be switched on and off by light. Time-resolved micropipette experiments show that the light-switchable adhesiveness of the flagella is a completely reversible process that is based on a redistribution of adhesion-promoting flagella-membrane proteins within seconds. Light-switchable adhesion enables the cell to regulate the transition between planktonic and surface-associated state, which possibly represents a significant biological advantage for photoactive microorganisms. In terms of the colonization of surfaces and the formation of biofilms, the findings might have immediate economic and environmental relevance in biotechnological settings, such as photo-bioreactors for the sustainable production of biofuels.

Controlled release of ascorbic acid from gelatin hydrogel attenuates abdominal aortic aneurysm formation in rat experimental abdominal aortic aneurysm model.

PubMed

Tanaka, Akiko; Hasegawa, Tomomi; Morimoto, Keisuke; Bao, Wulan; Yu, Jie; Okita, Yutaka; Tabata, Yasuhiko; Okada, Kenji

2014-09-01

Abdominal aortic aneurysms (AAAs) are associated with oxidative stress and inflammatory response. We investigated the hypothesis that the known antioxidant ascorbic acid, which can also promote elastin and collagen production by smooth muscle cells, would prevent AAA formation in a rat model. An intraluminal elastase and extraluminal calcium chloride-induced rat AAA model was used, and the animals were divided into three groups: control (group C, n = 18), the aorta wrapped with a saline-impregnated gelatin hydrogel sheet (group G, n = 18), and the aorta wrapped with a gelatin hydrogel sheet incorporating ascorbic acid (group A, n = 18). Wrapping of the sheet was completed at the end of treatment for AAA creation. The aortic dilatation ratio was measured, and aortic tissues were further examined for oxidative stress and oxidative DNA damage using biochemical and histologic techniques. Aortic dilatation at both 4 and 8 weeks was inhibited in group A (dilatation ratio [%] at 4 weeks: 186.2 ± 21.8 in group C, 152.3 ± 10.2 in group G, 126.8 ± 11.6 in group A; P < .0001; dilatation ratio [%] at 8 weeks: 219.3 ± 37.5 in group C, 194.0 ± 11.6 in group G, 145.7 ± 8.3 in group A; P = .0002). Elastin and collagen content were significantly preserved in group A (elastin, P = .0015; collagen, P < .0001). The messenger RNA expressions of matrix metalloproteinase (MMP)-9, monocyte chemotactic protein-1, interleukin-1β, and tissue necrosis factor-α (P = .0024, P < .0001, P < .0001, and P < .0001, respectively) were downregulated in group A (P = .0024), whereas tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 were both upregulated in group A (TIMP-1, P = .0014; TIMP-2, P < .0001). Gelatin zymography showed activities of pro-MMP-2, MMP-2, and MMP-9 were significantly suppressed in group C (P < .0001 for each). Reactive oxygen species expression and 8-hydroxydeoxyguanosine and cluster of differentiation 68 staining were significantly suppressed in group A (reactive

On the prediction of monocyte deposition in abdominal aortic aneurysms using computational fluid dynamics.

PubMed

Hardman, David; Doyle, Barry J; Semple, Scott I K; Richards, Jennifer M J; Newby, David E; Easson, William J; Hoskins, Peter R

2013-10-01

In abdominal aortic aneurysm disease, the aortic wall is exposed to intense biological activity involving inflammation and matrix metalloproteinase-mediated degradation of the extracellular matrix. These processes are orchestrated by monocytes and rather than affecting the aorta uniformly, damage and weaken focal areas of the wall leaving it vulnerable to rupture. This study attempts to model numerically the deposition of monocytes using large eddy simulation, discrete phase modelling and near-wall particle residence time. The model was first applied to idealised aneurysms and then to three patient-specific lumen geometries using three-component inlet velocities derived from phase-contrast magnetic resonance imaging. The use of a novel, variable wall shear stress-limiter based on previous experimental data significantly improved the results. Simulations identified a critical diameter (1.8 times the inlet diameter) beyond which significant monocyte deposition is expected to occur. Monocyte adhesion occurred proximally in smaller abdominal aortic aneurysms and distally as the sac expands. The near-wall particle residence time observed in each of the patient-specific models was markedly different. Discrete hotspots of monocyte residence time were detected, suggesting that the monocyte infiltration responsible for the breakdown of the abdominal aortic aneurysm wall occurs heterogeneously. Peak monocyte residence time was found to increase with aneurysm sac size. Further work addressing certain limitations is needed in a larger cohort to determine clinical significance.

The effect of TISSEEL fibrin sealant on seroma formation following complex abdominal wall hernia repair: a single institutional review and derived cost analysis.

PubMed

Azoury, S C; Rodriguez-Unda, N; Soares, K C; Hicks, C W; Baltodano, P A; Poruk, K E; Hu, Q L; Cooney, C M; Cornell, P; Burce, K; Eckhauser, F E

2015-12-01

The authors evaluated the ability of a fibrin sealant (TISSEEL™: Baxter Healthcare Corp, Deerfield, IL, USA) to reduce the incidence of post-operative seroma following abdominal wall hernia repair. We performed a 4-year retrospective review of patients undergoing abdominal wall hernia repair, with and without TISSEEL, by a single surgeon (FEE) at The Johns Hopkins Hospital. Demographics, surgical risk factors, operative data and 30-day outcomes, including wound complications and related interventions, were compared. The quantity and cost of Tisseel per case was reviewed. A total of 250 patients were evaluated: 127 in the TISSEEL group and 123 in the non-TISSEEL control group. The average age for both groups was 56.6 years (P = 0.97). The majority of patients were female (TISSEEL 52.8%, non-TISSEEL 56.1%, P = 0.59) and ASA Class III (TISSEEL 56.7%, non-TISSEEL 58.5%, P = 0.40). There was no difference in the average defect size for both groups (TISSEEL 217 ± 187.6 cm(2), non-TISSEEL 161.3 ± 141.5 cm(2), P = 0.36). Surgical site occurrences occurred in 18.1% of the TISSEEL and 13% of the non-TISSEEL group (P = 0.27). There was a trend towards an increased incidence of seroma in the TISSEEL group (TISSEEL 11%, non-TISSEEL 4.9%, P = 0.07). A total of $124,472.50 was spent on TISSEEL, at an average cost of $995.78 per case. In the largest study to date, TISSEEL™ application offered no advantage for the reduction of post-operative seroma formation following complex abdominal hernia repair. Moreover, the use of this sealant was associated with significant costs.

Effects of cryopreservation on excretory function, cellular adhesion molecules and vessel lumen formation in human umbilical vein endothelial cells.

PubMed

Cai, Guoping; Lai, Binbin; Hong, Huaxing; Lin, Peng; Chen, Weifu; Zhu, Zhong; Chen, Haixiao

2017-07-01

Cryopreservation is widely used in regenerative medicine for tissue preservation. In the present study, the effects of cryopreservation on excretory function, cellular adhesion molecules and vessel lumen formation in human umbilical vein endothelial cells (HUVECs) were investigated. After 0, 4, 8, 12 or 24 weeks of cryopreservation in liquid nitrogen, the HUVECs were thawed. The excretory functions markers (endothelin‑1, prostaglandin E1, von Willebrand factor and nitric oxide) of HUVECs were measured by ELISA assay. The expression of intercellular adhesion molecule‑1 (ICAM‑1) in HUVECs was analyzed using flow cytometry. An angiogenesis assay was used to determine the angiogeneic capabilities of the thawed HUVECs. The results demonstrated that cryopreserved/thawed and recultivated HUVECs were unsuitable for tissue‑engineered microvascular construction. Specifically, the excretory function of the cells was significantly decreased in the post‑cryopreserved HUVECs at 24 weeks. In addition, the level of ICAM‑1 in HUVECs was significantly upregulated from the fourth week of cryopreservation. Furthermore, the tube‑like structure‑forming potential was weakened with increasing cryopreservation duration, and the numbers of lumen and the length of the pipeline were decreased in the thawed HUVECs, in a time‑dependent manner. In conclusion, the results of the present study revealed that prolonged cryopreservation may lead to HUVEC dysfunction and did not create stable cell lines for tissue‑engineered microvascular construction.

Combinatorial materials research applied to the development of new surface coatings VII: An automated system for adhesion testing

NASA Astrophysics Data System (ADS)

Chisholm, Bret J.; Webster, Dean C.; Bennett, James C.; Berry, Missy; Christianson, David; Kim, Jongsoo; Mayo, Bret; Gubbins, Nathan

2007-07-01

An automated, high-throughput adhesion workflow that enables pseudobarnacle adhesion and coating/substrate adhesion to be measured on coating patches arranged in an array format on 4×8in.2 panels was developed. The adhesion workflow consists of the following process steps: (1) application of an adhesive to the coating array; (2) insertion of panels into a clamping device; (3) insertion of aluminum studs into the clamping device and onto coating surfaces, aligned with the adhesive; (4) curing of the adhesive; and (5) automated removal of the aluminum studs. Validation experiments comparing data generated using the automated, high-throughput workflow to data obtained using conventional, manual methods showed that the automated system allows for accurate ranking of relative coating adhesion performance.

Development of phosphorylated adhesives

NASA Technical Reports Server (NTRS)

Bilow, N.; Giants, T. W.; Jenkins, R. K.; Campbell, P. L.

1983-01-01

The synthesis of epoxy prepolymers containing phosphorus was carried out in such a manner as to provide adhesives containing at least 5 percent of this element. The purpose of this was to impart fire retardant properties to the adhesive. The two epoxy derivatives, bis(4-glycidyl-oxyphenyl)phenylphosphine oxide and bis(4-glycidyl-2-methoxyphenyl)phenylphosphonate, and a curing agent, bis(3-aminophenyl)methylphosphine oxide, were used in conjunction with one another and along with conventional epoxy resins and curing agents to bond Tedlar and Polyphenylethersulfone films to Kerimid-glass syntactic foam-filled honeycomb structures. Elevated temperatures are required to cure the epoxy resins with the phosphorus-contaning diamine; however, when Tedlar is being bonded, lower curing temperatures must be used to avoid shrinkage and the concomitant formation of surface defects. Thus, the phosphorus-containing aromatic amine curing agent cannot be used alone, although it is possible to use it in conjunction with an aliphatic amine which would allow lower cure temperatures to be used. The experimental epoxy resins have not provided adhesive bonds quite as strong as those provided by Epon 828 when compared in peel tests, but the differences are not very significant. It should be noted, if optimum properties are to be realized. In any case the fire retardant characteristics of the neat resin systems obtained are quite pronounced, since in most cases the self-extinguishing properties are evident almost instantly when specimens are removed from a flame.

Gastrografin for uncomplicated adhesive small bowel obstruction in children.

PubMed

Bonnard, A; Kohaut, J; Sieurin, A; Belarbi, N; El Ghoneimi, A

2011-12-01

The risk of bowel injury during surgery for small bowel obstruction (SBO) has generated interest in conservative treatment modalities. Few data are available on conservative Gastrografin treatment for SBO in children. We prospectively included patients with uncomplicated adhesive SBO managed at a pediatric center between March 2009 and September 2010. Patients who were unimproved after 48 h of conservative treatment received 50-100 ml of Gastrografin. If Gastrografin was seen in the cecum on the abdominal radiograph 4-6 h later, feeding was initiated and the patient was discharged on the same day. Each patient was matched to 2 controls on the number of previous SBO episodes. The primary outcome was length of hospital stay (>3 days), and the secondary outcome was time from admission to first feed (>2 days). Both were compared in the two groups using conditional logistic regression. The 8 patients admitted for SBO were matched to 16 controls. Gastrografin administration was associated with significantly lower risks of staying in the hospital longer than 3 days (P < 0.10) and waiting more than 2 days before the first feed. This preliminary study suggests that Gastrografin may be useful for managing adhesive SBO in children.

Ectodermal Wnt signaling regulates abdominal myogenesis during ventral body wall development.

PubMed

Zhang, Lingling; Li, Hanjun; Yu, Jian; Cao, Jingjing; Chen, Huihui; Zhao, Haixia; Zhao, Jianzhi; Yao, Yiyun; Cheng, Huihui; Wang, Lifang; Zhou, Rujiang; Yao, Zhengju; Guo, Xizhi

2014-03-01

Defects of the ventral body wall are prevalent birth anomalies marked by deficiencies in body wall closure, hypoplasia of the abdominal musculature and multiple malformations across a gamut of organs. However, the mechanisms underlying ventral body wall defects remain elusive. Here, we investigated the role of Wnt signaling in ventral body wall development by inactivating Wls or β-catenin in murine abdominal ectoderm. The loss of Wls in the ventral epithelium, which blocks the secretion of Wnt proteins, resulted in dysgenesis of ventral musculature and genito-urinary tract during embryonic development. Molecular analyses revealed that the dermis and myogenic differentiation in the underlying mesenchymal progenitor cells was perturbed by the loss of ectodermal Wls. The activity of the Wnt-Pitx2 axis was impaired in the ventral mesenchyme of the mutant body wall, which partially accounted for the defects in ventral musculature formation. In contrast, epithelial depletion of β-catenin or Wnt5a did not resemble the body wall defects in the ectodermal Wls mutant. These findings indicate that ectodermal Wnt signaling instructs the underlying mesodermal specification and abdominal musculature formation during ventral body wall development, adding evidence to the theory that ectoderm-mesenchyme signaling is a potential unifying mechanism for the origin of ventral body wall defects. Copyright © 2013 Elsevier Inc. All rights reserved.

Protein adhesives

Treesearch

Charles R. Frihart; Linda F. Lorenz

2018-01-01

Nature uses a wide variety of chemicals for providing adhesion internally (e.g., cell to cell) and externally (e.g., mussels to ships and piers). This adhesive bonding is chemically and mechanically complex, involving a variety of proteins, carbohydrates, and other compounds.Consequently,the effect of protein structures on adhesive properties is only partially...

Modeling cell adhesion and proliferation: a cellular-automata based approach.

PubMed

Vivas, J; Garzón-Alvarado, D; Cerrolaza, M

Cell adhesion is a process that involves the interaction between the cell membrane and another surface, either a cell or a substrate. Unlike experimental tests, computer models can simulate processes and study the result of experiments in a shorter time and lower costs. One of the tools used to simulate biological processes is the cellular automata, which is a dynamic system that is discrete both in space and time. This work describes a computer model based on cellular automata for the adhesion process and cell proliferation to predict the behavior of a cell population in suspension and adhered to a substrate. The values of the simulated system were obtained through experimental tests on fibroblast monolayer cultures. The results allow us to estimate the cells settling time in culture as well as the adhesion and proliferation time. The change in the cells morphology as the adhesion over the contact surface progress was also observed. The formation of the initial link between cell and the substrate of the adhesion was observed after 100 min where the cell on the substrate retains its spherical morphology during the simulation. The cellular automata model developed is, however, a simplified representation of the steps in the adhesion process and the subsequent proliferation. A combined framework of experimental and computational simulation based on cellular automata was proposed to represent the fibroblast adhesion on substrates and changes in a macro-scale observed in the cell during the adhesion process. The approach showed to be simple and efficient.

Retrospective comparison of abdominal ultrasonography and radiography in the investigation of feline abdominal disease

PubMed Central

Won, Wylen Wade; Sharma, Ajay; Wu, Wenbo

2015-01-01

Abdominal radiography and ultrasonography are commonly used as part of the initial diagnostic plan for cats with nonspecific signs of abdominal disease. This retrospective study compared the clinical usefulness of abdominal radiography and ultrasonography in 105 feline patients with signs of abdominal disease. The final diagnosis was determined more commonly with ultrasonography (59%) compared to radiography (25.7%). Ultrasonography was also able to provide additional clinically relevant information in 76% of cases, and changed or refined the diagnosis in 47% of cases. Based on these findings, ultrasonography may be sufficient as an initial diagnostic test for the investigation of feline abdominal disease. PMID:26483582

The Tribolium homeotic gene Abdominal is homologous to abdominal-A of the Drosophila bithorax complex

NASA Technical Reports Server (NTRS)

Stuart, J. J.; Brown, S. J.; Beeman, R. W.; Denell, R. E.; Spooner, B. S. (Principal Investigator)

1993-01-01

The Abdominal gene is a member of the single homeotic complex of the beetle, Tribolium castaneum. An integrated developmental genetic and molecular analysis shows that Abdominal is homologous to the abdominal-A gene of the bithorax complex of Drosophila. abdominal-A mutant embryos display strong homeotic transformations of the anterior abdomen (parasegments 7-9) to PS6, whereas developmental commitments in the posterior abdomen depend primarily on Abdominal-B. In beetle embryos lacking Abdominal function, parasegments throughout the abdomen are transformed to PS6. This observation demonstrates the general functional significance of parasegmental expression among insects and shows that the control of determinative decisions in the posterior abdomen by homeotic selector genes has undergone considerable evolutionary modification.

The Tribolium homeotic gene Abdominal is homologous to abdominal-A of the Drosophila bithorax complex.

PubMed

Stuart, J J; Brown, S J; Beeman, R W; Denell, R E

1993-01-01

The Abdominal gene is a member of the single homeotic complex of the beetle, Tribolium castaneum. An integrated developmental genetic and molecular analysis shows that Abdominal is homologous to the abdominal-A gene of the bithorax complex of Drosophila. abdominal-A mutant embryos display strong homeotic transformations of the anterior abdomen (parasegments 7-9) to PS6, whereas developmental commitments in the posterior abdomen depend primarily on Abdominal-B. In beetle embryos lacking Abdominal function, parasegments throughout the abdomen are transformed to PS6. This observation demonstrates the general functional significance of parasegmental expression among insects and shows that the control of determinative decisions in the posterior abdomen by homeotic selector genes has undergone considerable evolutionary modification.

Simulated microgravity does not alter epithelial cell adhesion to matrix and other molecules

NASA Technical Reports Server (NTRS)

Jessup, J. M.; Brown, K.; Ishii, S.; Ford, R.; Goodwin, T. J.; Spaulding, G.

1994-01-01

Microgravity has advantages for the cultivation of tissues with high fidelity; however, tissue formation requires cellular recognition and adhesion. We tested the hypothesis that simulated microgravity does not affect cell adhesion. Human colorectal carcinoma cells were cultured in the NASA Rotating Wall Vessel (RWV) under low shear stress with randomization of the gravity vector that simulates microgravity. After 6 - 7 days, cells were assayed for binding to various substrates and compared to cells grown in standard tissue culture flasks and static suspension cultures. The RWV cultures bound as well to basement membrane proteins and to Carcinoembryonic Antigen (CEA), an intercellular adhesion molecule, as control cultures did. Thus, microgravity does not alter epithelial cell adhesion and may be useful for tissue engineering.

[Differential diagnosis of abdominal pain].

PubMed

Frei, Pascal

2015-09-02

Despite the frequency of functional abdominal pain, potentially dangerous causes of abdominal pain need to be excluded. Medical history and clinical examination must focus on red flags and signs for imflammatory or malignant diseases. See the patient twice in the case of severe and acute abdominal pain if lab parameters or radiological examinations are normal. Avoid repeated and useless X-ray exposure whenever possible. In the case of subacute or chronic abdominal pain, lab tests such as fecal calprotectin, helicobacter stool antigen and serological tests for celiac disease are very useful. Elderly patients may show atypical or missing clinical signs. Take care of red herrings and be skeptical whether your initial diagnosis is really correct. Abdominal pain can frequently be an abdominal wall pain.

Switchable bio-inspired adhesives

NASA Astrophysics Data System (ADS)

Kroner, Elmar

2015-03-01

Geckos have astonishing climbing abilities. They can adhere to almost any surface and can run on walls and even stick to ceilings. The extraordinary adhesion performance is caused by a combination of a complex surface pattern on their toes and the biomechanics of its movement. These biological dry adhesives have been intensely investigated during recent years because of the unique combination of adhesive properties. They provide high adhesion, allow for easy detachment, can be removed residue-free, and have self-cleaning properties. Many aspects have been successfully mimicked, leading to artificial, bio-inspired, patterned dry adhesives, and were addressed and in some aspects they even outperform the adhesion capabilities of geckos. However, designing artificial patterned adhesion systems with switchable adhesion remains a big challenge; the gecko's adhesion system is based on a complex hierarchical surface structure and on advanced biomechanics, which are both difficult to mimic. In this paper, two approaches are presented to achieve switchable adhesion. The first approach is based on a patterned polydimethylsiloxane (PDMS) polymer, where adhesion can be switched on and off by applying a low and a high compressive preload. The switch in adhesion is caused by a reversible mechanical instability of the adhesive silicone structures. The second approach is based on a composite material consisting of a Nickel- Titanium (NiTi) shape memory alloy and a patterned adhesive PDMS layer. The NiTi alloy is trained to change its surface topography as a function of temperature, which results in a change of the contact area and of alignment of the adhesive pattern towards a substrate, leading to switchable adhesion. These examples show that the unique properties of bio-inspired adhesives can be greatly improved by new concepts such as mechanical instability or by the use of active materials which react to external stimuli.

Assay for adhesion and agar invasion in S. cerevisiae.

PubMed

Guldal, Cemile G; Broach, James

2006-11-08

Yeasts are found in natural biofilms, where many microorganisms colonize surfaces. In artificial environments, such as surfaces of man-made objects, biofilms can reduce industrial productivity, destroy structures, and threaten human life. 1-3 On the other hand, harnessing the power of biofilms can help clean the environment and generate sustainable energy. 4-8 The ability of S. cerevisiae to colonize surfaces and participate in complex biofilms was mostly ignored until the rediscovery of the differentiation programs triggered by various signaling pathways and environmental cues in this organism. 9, 10 The continuing interest in using S. cerevisiae as a model organism to understand the interaction and convergence of signaling pathways, such as the Ras-PKA, Kss1 MAPK, and Hog1 osmolarity pathways, quickly placed S. cerevisiae in the junction of biofilm biology and signal transduction research. 11-20 To this end, differentiation of yeast cells into long, adhesive, pseudohyphal filaments became a convenient readout for the activation of signal transduction pathways upon various environmental changes. However, filamentation is a complex collection of phenotypes, which makes assaying for it as if it were a simple phenotype misleading. In the past decade, several assays were successfully adopted from bacterial biofilm studies to yeast research, such as MAT formation assays to measure colony spread on soft agar and crystal violet staining to quantitatively measure cell-surface adherence. 12, 21 However, there has been some confusion in assays developed to qualitatively assess the adhesive and invasive phenotypes of yeast in agar. Here, we present a simple and reliable method for assessing the adhesive and invasive quality of yeast strains with easy-to-understand steps to isolate the adhesion assessment from invasion assessment. Our method, adopted from previous studies, 10, 16 involves growing cells in liquid media and plating on differential nutrient conditions for growth

Assay for Adhesion and Agar Invasion in S. cerevisiae

PubMed Central

Guldal, Cemile G; Broach, James

2006-01-01

Yeasts are found in natural biofilms, where many microorganisms colonize surfaces. In artificial environments, such as surfaces of man-made objects, biofilms can reduce industrial productivity, destroy structures, and threaten human life. 1-3 On the other hand, harnessing the power of biofilms can help clean the environment and generate sustainable energy. 4-8 The ability of S. cerevisiae to colonize surfaces and participate in complex biofilms was mostly ignored until the rediscovery of the differentiation programs triggered by various signaling pathways and environmental cues in this organism. 9, 10 The continuing interest in using S. cerevisiae as a model organism to understand the interaction and convergence of signaling pathways, such as the Ras-PKA, Kss1 MAPK, and Hog1 osmolarity pathways, quickly placed S. cerevisiae in the junction of biofilm biology and signal transduction research. 11-20 To this end, differentiation of yeast cells into long, adhesive, pseudohyphal filaments became a convenient readout for the activation of signal transduction pathways upon various environmental changes. However, filamentation is a complex collection of phenotypes, which makes assaying for it as if it were a simple phenotype misleading. In the past decade, several assays were successfully adopted from bacterial biofilm studies to yeast research, such as MAT formation assays to measure colony spread on soft agar and crystal violet staining to quantitatively measure cell-surface adherence. 12, 21 However, there has been some confusion in assays developed to qualitatively assess the adhesive and invasive phenotypes of yeast in agar. Here, we present a simple and reliable method for assessing the adhesive and invasive quality of yeast strains with easy-to-understand steps to isolate the adhesion assessment from invasion assessment. Our method, adopted from previous studies, 10, 16 involves growing cells in liquid media and plating on differential nutrient conditions for growth

The Role of Glottal Surface Adhesion on Vocal Folds Biomechanics

PubMed Central

Bhattacharya, Pinaki; Siegmund, Thomas

2014-01-01

The airway surface liquid (ASL) is a very thin mucus layer and covers the vocal fold (VF) surface. Adhesion mediated by the ASL occurs during phonation as the VFs separate after collision. Such adhesion is hypothesized to determine voice quality and health. However, biomechanical insights into the adhesive processes during VF oscillation are lacking. Here, a computational study is reported on self-sustained VF vibration involving contact and adhesion. The VF structural model and the glottal airflow are considered fully three-dimensional. The mechanical behavior of the ASL is described through a constitutive traction–separation law where mucosal cohesive strength, cohesive energy and rupture length enter. Cohesive energy values considered are bound below by the cohesive energy of water at standard temperature and pressure. Cohesive strength values considered are bound above by prior reported data on the adhesive strength of mucosal surface of rat small intestine. This model introduces a mechanical length scale into the analysis. The sensitivity of various aspects of VF dynamics such as flow-declination rate, VF separation under adhesive condition and formation of multiple local fluid bridges is determined in relation to specific ASL adhesive properties. It is found that for the ASL considered here, the characteristics of the VF separation process are of debond type. Instabilities lead to the breakup of the bond area into several smaller bond patches. Such finding is consistent with in-vivo observations. PMID:25034504

Carbon nanotube dry adhesives with temperature-enhanced adhesion over a large temperature range.

PubMed

Xu, Ming; Du, Feng; Ganguli, Sabyasachi; Roy, Ajit; Dai, Liming

2016-11-16

Conventional adhesives show a decrease in the adhesion force with increasing temperature due to thermally induced viscoelastic thinning and/or structural decomposition. Here, we report the counter-intuitive behaviour of carbon nanotube (CNT) dry adhesives that show a temperature-enhanced adhesion strength by over six-fold up to 143 N cm -2 (4 mm × 4 mm), among the strongest pure CNT dry adhesives, over a temperature range from -196 to 1,000 °C. This unusual adhesion behaviour leads to temperature-enhanced electrical and thermal transports, enabling the CNT dry adhesive for efficient electrical and thermal management when being used as a conductive double-sided sticky tape. With its intrinsic thermal stability, our CNT adhesive sustains many temperature transition cycles over a wide operation temperature range. We discover that a 'nano-interlock' adhesion mechanism is responsible for the adhesion behaviour, which could be applied to the development of various dry CNT adhesives with novel features.

Rubber contact mechanics: adhesion, friction and leakage of seals.

PubMed

Tiwari, A; Dorogin, L; Tahir, M; Stöckelhuber, K W; Heinrich, G; Espallargas, N; Persson, B N J

2017-12-13

We study the adhesion, friction and leak rate of seals for four different elastomers: Acrylonitrile Butadiene Rubber (NBR), Ethylene Propylene Diene (EPDM), Polyepichlorohydrin (GECO) and Polydimethylsiloxane (PDMS). Adhesion between smooth clean glass balls and all the elastomers is studied both in the dry state and in water. In water, adhesion is observed for the NBR and PDMS elastomers, but not for the EPDM and GECO elastomers, which we attribute to the differences in surface energy and dewetting. The leakage of water is studied with rubber square-ring seals squeezed against sandblasted glass surfaces. Here we observe a strongly non-linear dependence of the leak rate on the water pressure ΔP for the elastomers exhibiting adhesion in water, while the leak rate depends nearly linearly on ΔP for the other elastomers. We attribute the non-linearity to some adhesion-related phenomena, such as dewetting or the (time-dependent) formation of gas bubbles, which blocks fluid flow channels. Finally, rubber friction is studied at low sliding speeds using smooth glass and sandblasted glass as substrates, both in the dry state and in water. The measured friction coefficients are compared to theory, and the origin of the frictional shear stress acting in the area of real contact is discussed. The NBR rubber, which exhibits the strongest adhesion both in the dry state and in water, also shows the highest friction both in the dry state and in water.

Calpain-2 Compensation Promotes Angiotensin II-Induced Ascending and Abdominal Aortic Aneurysms in Calpain-1 Deficient Mice

PubMed Central

Subramanian, Venkateswaran; Moorleghen, Jessica J.; Balakrishnan, Anju; Howatt, Deborah A.; Chishti, Athar H.; Uchida, Haruhito A.

2013-01-01

Background and Objective Recently, we demonstrated that angiotensin II (AngII)-infusion profoundly increased both aortic protein and activity of calpains, calcium-activated cysteine proteases, in mice. In addition, pharmacological inhibition of calpain attenuated AngII-induced abdominal aortic aneurysm (AA) in mice. Recent studies have shown that AngII infusion into mice leads to aneurysmal formation localized to the ascending aorta. However, the precise functional contribution of calpain isoforms (-1 or -2) in AngII-induced abdominal AA formation is not known. Similarly, a functional role of calpain in AngII-induced ascending AA remains to be defined. Using BDA-410, an inhibitor of calpains, and calpain-1 genetic deficient mice, we examined the relative contribution of calpain isoforms in AngII-induced ascending and abdominal AA development. Methodology/Results To investigate the relative contribution of calpain-1 and -2 in development of AngII-induced AAs, male LDLr −/− mice that were either calpain-1 +/+ or −/− were fed a saturated fat-enriched diet and infused with AngII (1,000 ng/kg/min) for 4 weeks. Calpain-1 deficiency had no significant effect on body weight or blood pressure during AngII infusion. Moreover, calpain-1 deficiency showed no discernible effects on AngII-induced ascending and abdominal AAs. Interestingly, AngII infusion induced increased expression of calpain-2 protein, thus compensating for total calpain activity in aortas of calpain-1 deficient mice. Oral administration of BDA-410, a calpain inhibitor, along with AngII-infusion significantly attenuated AngII-induced ascending and abdominal AA formation in both calpain-1 +/+ and −/− mice as compared to vehicle administered mice. Furthermore, BDA-410 administration attenuated AngII-induced aortic medial hypertrophy and macrophage accumulation. Western blot and immunostaining analyses revealed BDA-410 administration attenuated AngII-induced C-terminal fragmentation of filamin A, an

Adhesion enhancement of Al coatings on carbon/epoxy composite surfaces by atmospheric plasma

NASA Astrophysics Data System (ADS)

Coulon, J. F.; Tournerie, N.; Maillard, H.

2013-10-01

Adhesion strengths between aluminium thin film coatings and manufactured carbon/epoxy composite surfaces were measured by assessing fracture tensile strengths using pull-off tests. The effect of the substrate roughness (nm to μm) of these composite surfaces on adhesion was studied by examining the surface free energies and adhesion strengths. The adhesion strengths of the coatings varied significantly. To improve the coating adhesion, each composite surface was treated with atmospheric plasma prior to deposition, which resulted in an increase in the surface free energy from approximately 40 mJ/m2 to 70 mJ/m2 because the plasma pretreatment led to the formation of hydrophilic Csbnd O and Cdbnd O bonds on the composite surfaces, as demonstrated by X-ray photoelectron spectroscopy analyses. The adhesion strengths of the coatings were enhanced for all surface roughnesses studied. In our study, the effect of mechanical adhesion due to roughness was separated from the effect of modifying the chemical bonds with plasma activation. The adhesion ability of the pure resin was relatively weak. Increasing the surface roughness largely improved the adhesion of the resin surface. Plasma treatment of the pure resin also increased the surface adhesion. Our study shows that plasma activation effectively enhances the adhesion of manufactured composites, even when the surface roughness is on the order of microns. The ageing of the surface activation was also investigated, and the results demonstrate that atmospheric plasma has potential for use in the pretreatment of composite materials.

Proteomic dataset of the sea urchin Paracentrotus lividus adhesive organs and secreted adhesive.

PubMed

Lebesgue, Nicolas; da Costa, Gonçalo; Ribeiro, Raquel Mesquita; Ribeiro-Silva, Cristina; Martins, Gabriel G; Matranga, Valeria; Scholten, Arjen; Cordeiro, Carlos; Heck, Albert J R; Santos, Romana

2016-06-01

Sea urchins have specialized adhesive organs called tube feet, which mediate strong but reversible adhesion. Tube feet are composed by a disc, producing adhesive and de-adhesive secretions for substratum attachment, and a stem for movement. After detachment the secreted adhesive remains bound to the substratum as a footprint. Recently, a label-free quantitative proteomic approach coupled with the latest mass-spectrometry technology was used to analyze the differential proteome of Paracentrotus lividus adhesive organ, comparing protein expression levels in the tube feet adhesive part (the disc) versus the non-adhesive part (the stem), and also to profile the proteome of the secreted adhesive (glue). This data article contains complementary figures and results related to the research article "Deciphering the molecular mechanisms underlying sea urchin reversible adhesion: a quantitative proteomics approach" (Lebesgue et al., 2016) [1]. Here we provide a dataset of 1384 non-redundant proteins, their fragmented peptides and expression levels, resultant from the analysis of the tube feet differential proteome. Of these, 163 highly over-expressed tube feet disc proteins (>3-fold), likely representing the most relevant proteins for sea urchin reversible adhesion, were further annotated in order to determine the potential functions. In addition, we provide a dataset of 611 non-redundant proteins identified in the secreted adhesive proteome, as well as their functional annotation and grouping in 5 major protein groups related with adhesive exocytosis, and microbial protection. This list was further analyzed to identify the most abundant protein groups and pinpoint putative adhesive proteins, such as Nectin, the most abundant adhesive protein in sea urchin glue. The obtained data uncover the key proteins involved in sea urchins reversible adhesion, representing a step forward to the development of new wet-effective bio-inspired adhesives.

Proteomic dataset of the sea urchin Paracentrotus lividus adhesive organs and secreted adhesive

PubMed Central

Lebesgue, Nicolas; da Costa, Gonçalo; Ribeiro, Raquel Mesquita; Ribeiro-Silva, Cristina; Martins, Gabriel G.; Matranga, Valeria; Scholten, Arjen; Cordeiro, Carlos; Heck, Albert J.R.; Santos, Romana

2016-01-01

Sea urchins have specialized adhesive organs called tube feet, which mediate strong but reversible adhesion. Tube feet are composed by a disc, producing adhesive and de-adhesive secretions for substratum attachment, and a stem for movement. After detachment the secreted adhesive remains bound to the substratum as a footprint. Recently, a label-free quantitative proteomic approach coupled with the latest mass-spectrometry technology was used to analyze the differential proteome of Paracentrotus lividus adhesive organ, comparing protein expression levels in the tube feet adhesive part (the disc) versus the non-adhesive part (the stem), and also to profile the proteome of the secreted adhesive (glue). This data article contains complementary figures and results related to the research article “Deciphering the molecular mechanisms underlying sea urchin reversible adhesion: a quantitative proteomics approach” (Lebesgue et al., 2016) [1]. Here we provide a dataset of 1384 non-redundant proteins, their fragmented peptides and expression levels, resultant from the analysis of the tube feet differential proteome. Of these, 163 highly over-expressed tube feet disc proteins (>3-fold), likely representing the most relevant proteins for sea urchin reversible adhesion, were further annotated in order to determine the potential functions. In addition, we provide a dataset of 611 non-redundant proteins identified in the secreted adhesive proteome, as well as their functional annotation and grouping in 5 major protein groups related with adhesive exocytosis, and microbial protection. This list was further analyzed to identify the most abundant protein groups and pinpoint putative adhesive proteins, such as Nectin, the most abundant adhesive protein in sea urchin glue. The obtained data uncover the key proteins involved in sea urchins reversible adhesion, representing a step forward to the development of new wet-effective bio-inspired adhesives. PMID:27182547

Chronic abdominal wall pain and ultrasound-guided abdominal cutaneous nerve infiltration: a case series.

PubMed

Kanakarajan, Saravanakumar; High, Kristina; Nagaraja, Ravi

2011-03-01

Chronic abdominal wall pain occurs in about 10-30% of patients presenting with chronic abdominal pain. Entrapment of abdominal cutaneous nerves at the lateral border of the rectus abdominis muscle has been attributed as a cause of abdominal wall pain. We report our experience of treating such patients using ultrasound-guided abdominal cutaneous nerve infiltration. We conducted a retrospective audit of abdominal cutaneous nerve infiltration performed in the period between September 2008 to August 2009 in our center. All patients had received local anesthetic and steroid injection under ultrasound guidance. The response to the infiltration was evaluated in the post-procedure telephone review as well as in the follow-up clinic. Brief pain inventory (BPI) and numerical rating scale pain scores were collated from two points: the initial outpatient clinic and the follow up clinic up to 5 months following the injection. Nine patients had abdominal cutaneous nerve injections under ultrasound guidance in the period under review. Six patients reported 50% pain relief or more (responders) while three patients did not. Pain and BPI scores showed a decreasing trend in responders. The median duration of follow-up was 12 weeks. Ultrasound can reliably be used for infiltration of the abdominal cutaneous nerves. This will improve the safety as well as diagnostic utility of the procedure. Wiley Periodicals, Inc.

Alpinia katsumadai Extracts Inhibit Adhesion and Invasion of Campylobacter jejuni in Animal and Human Foetal Small Intestine Cell Lines.

PubMed

Pogačar, Maja Šikić; Klančnik, Anja; Bucar, Franz; Langerholc, Tomaž; Možina, Sonja Smole

2015-10-01

Alpinia katsumadai is used in traditional Chinese medicine for abdominal distention, pain, and diarrhoea. Campylobacter jejuni is the most common cause of bacterial food-borne diarrhoeal illnesses worldwide. Adhesion to gut epithelium is a prerequisite in its pathogenesis. The antimicrobial, cytotoxic, and anti-adhesive activities of a chemically characterised extract (SEE) and its residual material of hydrodistillation (hdSEE-R) from A. katsumadai seeds were evaluated against C. jejuni. Minimal inhibitory concentrations for SEE and hdSEE-R were 0.5 mg/mL and 0.25 mg/mL, respectively, and there was no cytotoxic influence in the anti-adhesion tests, as these were performed at much lower concentrations of these tested plant extracts. Adhesion of C. jejuni to pig (PSI) and human foetal (H4) small-intestine cell lines was significantly decreased at lower concentrations (0.2 to 50 µg/mL). In the same concentration range, the invasiveness of C. jejuni in PSI cells was reduced by 45% to 65% when they were treated with SEE or hdSEE-R. The hdSEE-R represents a bioactive waste with a high phenolic content and an anti-adhesive activity against C. jejuni and thus has the potential for use in pharmaceutical and food products. Copyright © 2015 John Wiley & Sons, Ltd.

Role of Water Soluble Contrast Agents in Assigning Patients to a Non-Operative Course in Adhesive Small Bowel Obstruction

PubMed Central

Wadani, Hamid AI; Al Awad, Naif Ibrahim; Hassan, Khairi Ahmed; Zakaria, Hazem Mohamed; Alaqeel, Faten O.

2011-01-01

Objectives Adhesive small bowel obstruction (SBO) is a common surgical emergency. It is estimated that at least 60% of SBO are due to post-operative adhesions. Water soluble contrast agents (gastrografin) have been used to identify patients who might be treated non-operatively. This study aims to determine the role of gastrografin in adhesive intestinal obstruction patients. Methods In this prospective study, 27 patients admitted between 1st August 2004 and 1st July 2006 with clinical signs suggestive of postoperative adhesive SBO met the inclusion criteria. After intravenous hydration, nasogastric tube insertion and complete suctioning of the gastric fluid, 100 ml of gastrograsfin was given and plain abdominal radiography was taken 6 hours and 24 hours if the contrast is not seen in the colon. Those in whom the contrast reached the colon in 24 hours were considered to have partial SBO and started oral intake. If gastrografin failed to reach the colon in 24 hours and the patient did not improve in the following 24 hours, laparotomy was performed. Results Conservative treatment was successful in 31 cases (91%) and 3 (9%) required operation. Patients treated conservatively had short hospital stay (mean=4 days) and tolerated oral feeding with no morbidity or mortality. Conclusion Oral gastrografin helps in the management of patients with postoperative adhesive SBO. PMID:22253960

Bioprosthetic tissue matrices in complex abdominal wall reconstruction.

PubMed

Broyles, Justin M; Abt, Nicholas B; Sacks, Justin M; Butler, Charles E

2013-12-01

Complex abdominal defects are difficult problems encountered by surgeons in multiple specialties. Although current evidence supports the primary repair of these defects with mesh reinforcement, it is unclear which mesh is superior for any given clinical scenario. The purpose of this review was to explore the characteristics of and clinical relevance behind bioprosthetic tissue matrices in an effort to better clarify their role in abdominal wall reconstruction. We reviewed the peer-reviewed literature on the use of bioprosthetic mesh in human subjects. Basic science articles and large retrospective and prospective reviews were included in author's analysis. The clinical performance and characteristics of 13 bioprosthetic tissue matrices were evaluated. The majority of the products evaluated perform well in contaminated fields, where the risk of wound-healing difficulties is high. Clinical outcomes, which included infection, reherniation, and bulge formation, were variable, and the majority of the studies had a mean follow-up of less than 24 months. Although bioprosthetic matrix has a multitude of indications within the growing field of abdominal wall reconstruction, the functionality, regenerative capacity, and long-term fate of these products have yet to be fully established. Furthermore, the clinical performance, indications, and contraindications for each type of matrix need to be fully evaluated in long-term outcome studies.

Platelet-independent adhesion of calcium-loaded erythrocytes to von Willebrand factor

PubMed Central

Bierings, Ruben; Meems, Henriet; Mul, Frederik P. J.; Geerts, Dirk; Vlaar, Alexander P. J.; Voorberg, Jan; Hordijk, Peter L.

2017-01-01

Adhesion of erythrocytes to endothelial cells lining the vascular wall can cause vaso-occlusive events that impair blood flow which in turn may result in ischemia and tissue damage. Adhesion of erythrocytes to vascular endothelial cells has been described in multiple hemolytic disorders, especially in sickle cell disease, but the adhesion of normal erythrocytes to endothelial cells has hardly been described. It was shown that calcium-loaded erythrocytes can adhere to endothelial cells. Because sickle erythrocyte adhesion to ECs can be enhanced by ultra-large von Willebrand factor multimers, we investigated whether calcium loading of erythrocytes could promote binding to endothelial cells via ultra-large von Willebrand factor multimers. We used (immunofluorescent) live-cell imaging of washed erythrocytes perfused over primary endothelial cells at venular flow rate. Using this approach, we show that calcium-loaded erythrocytes strongly adhere to histamine-stimulated primary human endothelial cells. This adhesion is mediated by ultra-large von Willebrand factor multimers. Von Willebrand factor knockdown or ADAMTS13 cleavage abolished the binding of erythrocytes to activated endothelial cells under flow. Platelet depletion did not interfere with erythrocyte binding to von Willebrand factor. Our results reveal platelet-independent adhesion of calcium-loaded erythrocytes to endothelium-derived von Willebrand factor. Erythrocyte adhesion to von Willebrand factor may be particularly relevant for venous thrombosis, which is characterized by the formation of erythrocyte-rich thrombi. PMID:28249049

Regulation of T-lymphocyte motility, adhesion and de-adhesion by a cell surface mechanism directed by low density lipoprotein receptor-related protein 1 and endogenous thrombospondin-1.

PubMed

Talme, Toomas; Bergdahl, Eva; Sundqvist, Karl-Gösta

2014-06-01

T lymphocytes are highly motile and constantly reposition themselves between a free-floating vascular state, transient adhesion and migration in tissues. The regulation behind this unique dynamic behaviour remains unclear. Here we show that T cells have a cell surface mechanism for integrated regulation of motility and adhesion and that integrin ligands and CXCL12/SDF-1 influence motility and adhesion through this mechanism. Targeting cell surface-expressed low-density lipoprotein receptor-related protein 1 (LRP1) with an antibody, or blocking transport of LRP1 to the cell surface, perturbed the cell surface distribution of endogenous thrombospondin-1 (TSP-1) while inhibiting motility and potentiating cytoplasmic spreading on intercellular adhesion molecule 1 (ICAM-1) and fibronectin. Integrin ligands and CXCL12 stimulated motility and enhanced cell surface expression of LRP1, intact TSP-1 and a 130,000 MW TSP-1 fragment while preventing formation of a de-adhesion-coupled 110 000 MW TSP-1 fragment. The appearance of the 130 000 MW TSP-1 fragment was inhibited by the antibody that targeted LRP1 expression, inhibited motility and enhanced spreading. The TSP-1 binding site in the LRP1-associated protein, calreticulin, stimulated adhesion to ICAM-1 through intact TSP-1 and CD47. Shear flow enhanced cell surface expression of intact TSP-1. Hence, chemokines and integrin ligands up-regulate a dominant motogenic pathway through LRP1 and TSP-1 cleavage and activate an associated adhesion pathway through the LRP1-calreticulin complex, intact TSP-1 and CD47. This regulation of T-cell motility and adhesion makes pro-adhesive stimuli favour motile responses, which may explain why T cells prioritize movement before permanent adhesion.

Spatial self-organization in hybrid models of multicellular adhesion

NASA Astrophysics Data System (ADS)

Bonforti, Adriano; Duran-Nebreda, Salva; Montañez, Raúl; Solé, Ricard

2016-10-01

Spatial self-organization emerges in distributed systems exhibiting local interactions when nonlinearities and the appropriate propagation of signals are at work. These kinds of phenomena can be modeled with different frameworks, typically cellular automata or reaction-diffusion systems. A different class of dynamical processes involves the correlated movement of agents over space, which can be mediated through chemotactic movement or minimization of cell-cell interaction energy. A classic example of the latter is given by the formation of spatially segregated assemblies when cells display differential adhesion. Here, we consider a new class of dynamical models, involving cell adhesion among two stochastically exchangeable cell states as a minimal model capable of exhibiting well-defined, ordered spatial patterns. Our results suggest that a whole space of pattern-forming rules is hosted by the combination of physical differential adhesion and the value of probabilities modulating cell phenotypic switching, showing that Turing-like patterns can be obtained without resorting to reaction-diffusion processes. If the model is expanded allowing cells to proliferate and die in an environment where diffusible nutrient and toxic waste are at play, different phases are observed, characterized by regularly spaced patterns. The analysis of the parameter space reveals that certain phases reach higher population levels than other modes of organization. A detailed exploration of the mean-field theory is also presented. Finally, we let populations of cells with different adhesion matrices compete for reproduction, showing that, in our model, structural organization can improve the fitness of a given cell population. The implications of these results for ecological and evolutionary models of pattern formation and the emergence of multicellularity are outlined.

Switching "on" and "off" the adhesion in stimuli-responsive elastomers.

PubMed

Kaiser, S; Radl, S V; Manhart, J; Ayalur-Karunakaran, S; Griesser, T; Moser, A; Ganser, C; Teichert, C; Kern, W; Schlögl, S

2018-03-28

The present work aims at the preparation of dry adhesives with switchable bonding properties by using the reversible nature of the [4πs+4πs] cycloaddition of anthracenes. Photo-responsive hydrogenated carboxylated nitrile butadiene rubber with photo-responsive pendant anthracene groups is prepared by one-pot synthesis. The formation of 3D networks relies on the photodimerization of the anthracene moieties upon UV exposure (λ > 300 nm). Controlled cleavage of the crosslink sites is achieved by either deep UV exposure (λ = 254 nm) or thermal dissociation at 70 °C. The kinetics of the optical and thermal cleavage routes are compared in thin films using UV-vis spectroscopy and their influence on the reversibility of the network is detailed. Going from thin films to free standing samples the modulation of the network structure and thermo-mechanical properties over repeated crosslinking and cleavage cycles are characterized by low-field NMR spectroscopy and dynamic mechanical analysis. The applicability of the stimuli-responsive networks as adhesives with reversible bonding properties is demonstrated. The results evidence that the reversibility of the crosslinking reaction enables a controlled switching "on" and "off" of adhesion properties. The recovery of the adhesion force amounts to 75 and 80% for photo- and thermal dissociation, respectively. Spatial control of adhesion properties is evidenced by adhesion force mapping experiments of photo-patterned films.

Interaction between mDia1 and ROCK in Rho-induced migration and adhesion of human dental pulp cells.

PubMed

Cheng, L; Xu, J; Qian, Y Y; Pan, H Y; Yang, H; Shao, M Y; Cheng, R; Hu, T

2017-01-01

To investigate the effects of mammalian homologue of Drosophila diaphanous-1(mDia1) and Rho-associated coiled-coil-containing protein kinase (ROCK) on the migration and adhesion of dental pulp cells (DPCs). Lysophosphatidic acid (LPA) was used to activate Rho signalling. mDia1 and ROCK were inhibited by short interfering RNA and the specific inhibitor, Y-27632, respectively. The migration of DPCs was assessed using the transwell migration assay and scratch test. Formation of cytoskeleton and focal adhesions(FAs) was observed by confocal laser scanning microscopy. Cell adhesion and spreading assays were performed. Phosphorylation of focal adhesion kinase (FAK) and paxillin was detected by Western blotting, and the bands were analysed using Adobe Photoshop CS5 software. All experiments were performed at least three times, and data were analysed with one-way anova and a post hoc test. LPA-triggered activation of Rho and inhibition of ROCK significantly increased the cell migration rate. Cell migration was inhibited by silencing mDia1. mDia1 silencing and ROCK inhibition suppressed the LPA-induced formation of the cytoskeleton, FA and phosphorylation of FAK and paxillin. Inhibition of ROCK or mDia1 facilitated early cell adhesion and spreading; by contrast, the combined inhibition of ROCK and mDia1 neutralized these effects. mDia1 promoted RhoA-induced migration of DPCs, but ROCK had an opposite effect. Both mDia1 and ROCK participated in cytoskeleton formation and adhesion of DPCs. The interactions between mDia1 and ROCK might influence dental pulp repair by determining the migration and adhesion of DPCs. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Chapter 9:Wood Adhesion and Adhesives

Treesearch

Charles R. Frihart

2013-01-01

The recorded history of bonding wood dates back at least 3000 years to the Egyptians (Skeist and Miron 1990, River 1994a), and adhesive bonding goes back to early mankind (Keimel 2003). Although wood and paper bonding are the largest applications for adhesives, some of the fundamental aspects leading to good bonds are not fully understood. Better understanding of these...

Formation mechanism and adhesive strength of a hydroxyapatite/TiO2 composite coating on a titanium surface prepared by micro-arc oxidation

NASA Astrophysics Data System (ADS)

Liu, Shimin; Li, Baoe; Liang, Chunyong; Wang, Hongshui; Qiao, Zhixia

2016-01-01

A hydroxyapatite (HA)/TiO2 composite coating was prepared on a titanium surface by one-step micro-arc oxidation (MAO). The formation mechanism of the composite coating was investigated and the adhesion of the coating to the substrate was also measured. The results showed that flocculent structures could be obtained during the early stages of treatment. As the treatment period extended, increasing amounts of Ca-P precipitate appeared on the surface, and the flocculent morphology transformed into a plate-like morphology. Then the plate-like calcium and phosphate salt self-assembled to form flower-like apatite. The Ca/P atomic ratio gradually decreased, indicating that the amounts of Ca2+ ions which diffused into the coating decreased more rapidly than that of PO43- or HPO42-. The adhesive strength between the apatite and TiO2 coating was improved. This improvement is attributed to the interlocking effect between the apatite and TiO2 layer which formed simultaneously during the early stages of the one-step MAO. This study shows that it is a promising method to prepare bioactive coating on a titanium surface.

Novel protein-repellent dental adhesive containing 2-methacryloyloxyethyl phosphorylcholine

PubMed Central

Zhang, Ning; Melo, Mary Anne S.; Bai, Yuxing; Xu, Hockin H. K.

2015-01-01

Objectives Biofilms at tooth-restoration margins can produce acids and cause secondary caries. A protein-repellent adhesive resin can potentially inhibition bacteria attachment and biofilm growth. However, there has been no report on protein-repellent dental resins. The objectives of this study were to develop a protein-repellent bonding agent incorporating 2-methacryloyloxyethyl phosphorylcholine (MPC), and to investigate its resistance to protein adsorption and biofilm growth for the first time. Methods MPC was incorporated into Scotchbond Multi-Purpose (SBMP) at 0%, 3.75%, 7.5%, 11.25%, and 15% by mass. Extracted human teeth were used to measure dentin shear bond strengths. Protein adsorption onto resins was determined by a micro bicinchoninic acid (BCA) method. A dental plaque microcosm biofilm model with human saliva as inoculum was used to measure biofilm metabolic activity and colony-forming unit (CFU) counts. Results Adding 7.5% MPC into primer and adhesive did not decrease the dentin bond strength, compared to control (p > 0.1). Incorporation of 7.5% of MPC achieved the lowest protein adsorption, which was 20-fold less than that of control. Incorporation of 7.5% of MPC greatly reduced bacterial adhesion, yielding biofilm total microorganism, total streptococci, and mutans streptococci CFU that were an order of magnitude less than control. Conclusions A protein-repellent dental adhesive resin was developed for the first time. Incorporation of MPC into primer and adhesive at 7.5% by mass greatly reduced the protein adsorption and bacterial adhesion, without compromising the dentin bond strength. The novel protein-repellent primer and adhesive are promising to inhibit biofilm formation and acid production, to protect the tooth-restoration margins and prevent secondary caries. PMID:25234652

Adhesion mechanisms in embryogenesis and in cancer invasion and metastasis.

PubMed

Thiery, J P; Boyer, B; Tucker, G; Gavrilovic, J; Valles, A M

1988-01-01

Cell-substratum and cell-cell adhesion mechanisms contribute to the development of animal form. The adhesive status of embryonic cells has been analysed during epithelial-mesenchymal cell interconversion and in cell migrations. Clear-cut examples of the modulation of cell adhesion molecules (CAMs) have been described at critical periods of morphogenesis. In chick embryos the three primary CAMs (N-CAM. L-CAM and N-cadherin) present early in embryogenesis are expressed later in a defined pattern during morphogenesis and histogenesis. The axial mesoderm derived from gastrulating cells expresses increasing amounts of N-cadherin and N-CAM. During metamerization these two adhesion molecules become abundant at somitic cell surfaces. Both CAMs are functional in an in vitro aggregation assay; however, the calcium-dependent adhesion molecule N-cadherin is more sensitive to perturbation by specific antibodies. Neural crest cells which separate from the neural epithelium lose their primary CAMs in a defined time-sequence. Adhesion to fibronectins via specific surface receptors becomes a predominant interaction during the migratory process, while some primary and secondary CAMs are expressed de novo during the ontogeny of the peripheral nervous system. In vitro, different fibronectin functional domains have been identified in the attachment, spreading and migration of neural crest cells. The fibronectin receptors which transduce the adhesive signals play a key role in the control of cell movement. All these results have prompted us to examine whether similar mechanisms operate in carcinoma cell invasion and metastasis. In vitro, rat bladder transitional carcinoma cells convert reversibly into invasive mesenchymal cells. A rapid modulation of adhesive properties is found during the epithelial-mesenchymal carcinoma cell interconversion. The different model systems analysed demonstrate that a limited repertoire of adhesion molecules, expressed in a well-defined spatiotemporal

Abdominal elephantiasis: a case report.

PubMed

Hanna, Dominique; Cloutier, Richard; Lapointe, Roch; Desgagné, Antoine

2004-01-01

Elephantiasis is a well-known condition in dermatology usually affecting the legs and external genitalia. It is characterized by chronic inflammation and obstruction of the lymphatic channels and by hypertrophy of the skin and subcutaneous tissues. The etiology is either idiopathic or caused by a variety of conditions such as chronic filarial disease, leprosy, leishmaniasis, and chronic recurrent cellulites. Elephantiasis of the abdominal wall is very rare. A complete review of the English and French literature showed only two cases reported in 1966 and 1973, respectively. We report a third case of abdominal elephantiasis and we briefly review this entity. We present the case of a 51-year-old woman who had progressively developed an enormous pediculated abdominal mass hanging down her knees. The skin was thickened, hyperpigmented, and fissured. She had a history of multiple abdominal cellulites. She underwent an abdominal lipectomy. Histopathology of the specimen confirmed the diagnosis of abdominal elephantiasis. Abdominal elephantiasis is a rare disease that represents end-stage failure of lymph drainage. Lipectomy should be considered in the management of this condition.

Impact of Age-Dependent Adventitia Inflammation on Structural Alteration of Abdominal Aorta in Hyperlipidemic Mice

PubMed Central

Sakamoto, Sumiharu; Tsuruda, Toshihiro; Hatakeyama, Kinta; Imamura, Takuroh; Asada, Yujiro; Kitamura, Kazuo

2014-01-01

Background The adventitia is suggested to contribute to vascular remodeling; however, the site-selective inflammatory responses in association with the development of atherosclerosis remain to be elucidated. Methods and Results Wild-type or apolipoprotein E knockout male C57BL/6J background mice were fed standard chow for 16, 32, and 52 weeks, and the morphology of the aortic arch, descending aorta, and abdominal aorta was compared. Atheromatous plaque formation progressed with age, particularly in the aortic arch and abdominal aorta but not in the descending aorta. In addition, we found that the numbers of macrophages, T-lymphocytes, and microvessels, assessed by anti-F4/80, CD3, and CD31 antibodies, were higher in the adventitia of the abdominal aorta at 52 weeks. These numbers were positively correlated with plaque formation, but negatively correlated with elastin content, resulting in the enlargement of the total vessel area. In aortic tissues, interleukin-6 levels increased in the atheromatous plaque with age, whereas the level of regulated on activation, normal T cell expressed and secreted (RANTES) increased with age, and compared with other sites, it was particularly distributed in inflammatory cells in the adventitia of the abdominal aorta. Conclusion This study suggests that adventitial inflammation contributes to the age-dependent structural alterations, and that the activation/inactivation of cytokines/chemokines is involved in the process. PMID:25153991

Thermal gelation and tissue adhesion of biomimetic hydrogels

PubMed Central

Burke, Sean A; Ritter-Jones, Marsha; Lee, Bruce P; Messersmith, Phillip B

2008-01-01

Marine and freshwater mussels are notorious foulers of natural and manmade surfaces, secreting specialized protein adhesives for rapid and durable attachment to wet substrates. Given the strong and water-resistant nature of mussel adhesive proteins, significant potential exists for mimicking their adhesive characteristics in bioinspired synthetic polymer materials. An important component of these proteins is L-3,4-dihydroxylphenylalanine (DOPA), an amino acid believed to contribute to mussel glue solidification through oxidation and crosslinking reactions. Synthetic polymers containing DOPA residues have previously been shown to crosslink into hydrogels upon the introduction of oxidizing reagents. Here we introduce a strategy for stimuli responsive gel formation of mussel adhesive protein mimetic polymers. Lipid vesicles with a bilayer melting transition of 37 °C were designed from a mixture of dipalmitoyl and dimyristoyl phosphatidylcholines and exploited for the release of a sequestered oxidizing reagent upon heating from ambient to physiologic temperature. Colorimetric studies indicated that sodium-periodate-loaded liposomes released their cargo at the phase transition temperature, and when used in conjunction with a DOPA-functionalized poly(ethylene glycol) polymer gave rise to rapid solidification of a crosslinked polymer hydrogel. The tissue adhesive properties of this biomimetic system were determined by in situ thermal gelation of liposome/polymer hydrogel between two porcine dermal tissue surfaces. Bond strength measurements showed that the bond formed by the adhesive hydrogel (mean = 35.1 kPa, SD = 12.5 kPa, n = 11) was several times stronger than a fibrin glue control tested under the same conditions. The results suggest a possible use of this biomimetic strategy for repair of soft tissues. PMID:18458476

Conductive Adhesive Based on Mussel-Inspired Graphene Decoration with Silver Nanoparticles.

PubMed

Casa, Marcello; Sarno, Maria; Liguori, Rosalba; Cirillo, Claudia; Rubino, Alfredo; Bezzeccheri, Emanuele; Liu, Johan; Ciambelli, Paolo

2018-02-01

Decoration with silver nanoparticles was obtained by coating graphene with a polydopamine layer, able to induce spontaneous metallic nanoparticles formation without any specific chemical interfacial modifier, neither using complex instrumentation. The choice of dopamine was inspired by the composition of adhesive proteins in mussels, related to their robust attach to solid surfaces. The synthesis procedure started from graphite and involved eco-friendly compounds, such as Vitamin C and glucose as reducing agent and water as reaction medium. Silver decorated graphene was inserted as secondary nanofiller in the formulation of a reference conductive adhesive based on epoxy resin and silver flakes. A wide characterization of the intermediate materials obtained along the step procedure for the adhesive preparation was carried out by several techniques. We have found that the presence of nanofiller yields, in addition to an improvement of the thermal conductivity (up to 7.6 W/m · K), a dramatic enhancement of the electrical conductivity of the adhesive. In particular, starting from 3 · 102 S/cm of the reference adhesive, we obtained a value of 4 · 104 S/cm at a nanofiller concentration of 11.5 wt%. The combined double filler conductivity was evaluated by Zallen's model. The effect of the temperature on the resistivity of the adhesive has been also studied.

In vitro comparison of intra-abdominal hypertension development after different temporary abdominal closure techniques.

PubMed

Benninger, Emanuel; Labler, Ludwig; Seifert, Burkhardt; Trentz, Otmar; Menger, Michael D; Meier, Christoph

2008-01-01

To compare volume reserve capacity (VRC) and development of intra-abdominal hypertension after different in vitro temporary abdominal closure (TAC) techniques. A model of the abdomen was designed. The abdominal wall was simulated with polychloroprene, a synthetic rubber compound. A lentil-shaped defect of 150 cm(2) was cut into the anterior aspect of the abdominal wall. TAC of this defect was performed by a zipper system (ZS), a bag silo closure (BSC), or a vacuum assisted closure (VAC) with subatmospheric pressures ranging from 0- to 200 mmHg. The model with intact abdominal wall served as reference. The model was filled with water to baseline level. The intra-abdominal pressure was increased in 2 mmHg steps from baseline level (6 mmHg) to 40 mmHg by adding volume to the system according to a standardized protocol. VRC with corresponding intra-abdominal pressure were analyzed and compared for the different TAC techniques. VRC was the highest after BSC at all pressure levels studied (P < 0.05). VAC and ZS resulted in significantly lower VRC compared with BSC and reference (P < 0.05). The magnitude of negative pressure on the VAC did not significantly influence the VRC. In the present in vitro model, BSC demonstrated the highest VRC of all evaluated TAC techniques. Different levels of subatmospheric pressures applied to the VAC did not affect VRC. The results for ZS and VAC indicate that these TAC techniques may increase the risk for recurrent intra-abdominal hypertension and should therefore not be used in high-risk patients during the initial phase after abdominal decompression.

Adhesive interactions of biologically inspired soft condensed matter

NASA Astrophysics Data System (ADS)

Anderson, Travers Heath

Improving our fundamental understanding of the surface interactions between complex materials is needed to improve existing materials and products as well as develop new ones. The object of this research was to apply the measurements of fundamental surface interactions to real world problems facing chemical engineers and materials scientists. I focus on three systems of biologically inspired soft condensed matter, with an emphasis on the adhesive interactions between them. The formation of phospholipid bilayers of the neutral lipid, dimyristoyl-phosphatidylcholine (DMPC) on silica surfaces from vesicles in aqueous solutions was investigated. The process involves five stages: vesicle adhesion to the substrate surfaces, steric interactions with neighboring vesicles, rupture, spreading via hydrophobic fusion of bilayer edges, and ejection of excess lipid, trapped water and ions into the solution. The forces between DMPC bilayers and silica were measured in the Surface Forces Apparatus (SFA) in phosphate buffered saline. The adhesion energy was found to be much stronger than the expected adhesion predicted by van der Waals interactions, likely due to an attractive electrostatic interaction. The effects of non-adsorbing cationic polyelectrolytes on the interactions between supported cationic surfactant bilayers were studied using the SFA. Addition of polyelectrolyte has a number of effects on the interactions including the induction of a depletion-attraction and screening of the double-layer repulsion. Calculations are made that allow for the conversion of the adhesion energy measured in the SFA to the overall interaction energy between vesicles in solution, which determines the stability behavior of vesicle dispersions. Mussels use a variety of dihydroxyphenyl-alanine (DOPA) rich proteins specifically tailored to adhering to wet surfaces. The SFA was used to study the role of DOPA on the adhesive properties of these proteins to TiO 2 and mica using both real mussel

Understanding Marine Mussel Adhesion

PubMed Central

Roberto, Francisco F.

2007-01-01

In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are water-impervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion. PMID:17990038

A physical description of the adhesion and aggregation of platelets

NASA Astrophysics Data System (ADS)

Chopard, Bastien; de Sousa, Daniel Ribeiro; Lätt, Jonas; Mountrakis, Lampros; Dubois, Frank; Yourassowsky, Catherine; Van Antwerpen, Pierre; Eker, Omer; Vanhamme, Luc; Perez-Morga, David; Courbebaisse, Guy; Lorenz, Eric; Hoekstra, Alfons G.; Boudjeltia, Karim Zouaoui

2017-04-01

The early stages of clot formation in blood vessels involve platelet adhesion-aggregation. Although these mechanisms have been extensively studied, gaps in their understanding still persist. We have performed detailed in vitro experiments, using the well-known Impact-R device, and developed a numerical model to better describe and understand this phenomenon. Unlike previous studies, we took into account the differential role of pre-activated and non-activated platelets, as well as the three-dimensional nature of the aggregation process. Our investigation reveals that blood albumin is a major parameter limiting platelet aggregate formation in our experiment. Simulations are in very good agreement with observations and provide quantitative estimates of the adhesion and aggregation rates that are hard to measure experimentally. They also provide a value of the effective diffusion of platelets in blood subject to the shear rate produced by the Impact-R.

Abdominal hernias: Radiological features

PubMed Central

Lassandro, Francesco; Iasiello, Francesca; Pizza, Nunzia Luisa; Valente, Tullio; Stefano, Maria Luisa Mangoni di Santo; Grassi, Roberto; Muto, Roberto

2011-01-01

Abdominal wall hernias are common diseases of the abdomen with a global incidence approximately 4%-5%. They are distinguished in external, diaphragmatic and internal hernias on the basis of their localisation. Groin hernias are the most common with a prevalence of 75%, followed by femoral (15%) and umbilical (8%). There is a higher prevalence in males (M:F, 8:1). Diagnosis is usually made on physical examination. However, clinical diagnosis may be difficult, especially in patients with obesity, pain or abdominal wall scarring. In these cases, abdominal imaging may be the first clue to the correct diagnosis and to confirm suspected complications. Different imaging modalities are used: conventional radiographs or barium studies, ultrasonography and Computed Tomography. Imaging modalities can aid in the differential diagnosis of palpable abdominal wall masses and can help to define hernial contents such as fatty tissue, bowel, other organs or fluid. This work focuses on the main radiological findings of abdominal herniations. PMID:21860678

Fibronectin in cell adhesion and migration via N-glycosylation

PubMed Central

Hsiao, Cheng-Te; Cheng, Hung-Wei; Huang, Chi-Ming; Li, Hao-Ru; Ou, Meng-Hsin; Huang, Jie-Rong; Khoo, Kay-Hooi; Yu, Helen Wenshin; Chen, Yin-Quan; Wang, Yang-Kao; Chiou, Arthur; Kuo, Jean-Cheng

2017-01-01

Directed cell migration is an important step in effective wound healing and requires the dynamic control of the formation of cell-extracellular matrix interactions. Plasma fibronectin is an extracellular matrix glycoprotein present in blood plasma that plays crucial roles in modulating cellular adhesion and migration and thereby helping to mediate all steps of wound healing. In order to seek safe sources of plasma fibronectin for its practical use in wound dressing, we isolated fibronectin from human (homo) and porcine plasma and demonstrated that both have a similar ability as a suitable substrate for the stimulation of cell adhesion and for directing cell migration. In addition, we also defined the N-glycosylation sites and N-glycans present on homo and porcine plasma fibronectin. These N-glycosylation modifications of the plasma fibronectin synergistically support the integrin-mediated signals to bring about mediating cellular adhesion and directed cell migration. This study not only determines the important function of N-glycans in both homo and porcine plasma fibronectin-mediated cell adhesion and directed cell migration, but also reveals the potential applications of porcine plasma fibronectin if it was applied as a material for clinical wound healing and tissue repair. PMID:29050309

Deregulation of focal adhesion formation and cytoskeletal tension due to loss of A-type lamins.

PubMed

Corne, Tobias D J; Sieprath, Tom; Vandenbussche, Jonathan; Mohammed, Danahe; Te Lindert, Mariska; Gevaert, Kris; Gabriele, Sylvain; Wolf, Katarina; De Vos, Winnok H

2017-09-03

The nuclear lamina mechanically integrates the nucleus with the cytoskeleton and extracellular environment and regulates gene expression. These functions are exerted through direct and indirect interactions with the lamina's major constituent proteins, the A-type lamins, which are encoded by the LMNA gene. Using quantitative stable isotope labeling-based shotgun proteomics we have analyzed the proteome of human dermal fibroblasts in which we have depleted A-type lamins by means of a sustained siRNA-mediated LMNA knockdown. Gene ontology analysis revealed that the largest fraction of differentially produced proteins was involved in actin cytoskeleton organization, in particular proteins involved in focal adhesion dynamics, such as actin-related protein 2 and 3 (ACTR2/3), subunits of the ARP2/3 complex, and fascin actin-bundling protein 1 (FSCN1). Functional validation using quantitative immunofluorescence showed a significant reduction in the size of focal adhesion points in A-type lamin depleted cells, which correlated with a reduction in early cell adhesion capacity and an increased cell motility. At the same time, loss of A-type lamins led to more pronounced stress fibers and higher traction forces. This phenotype could not be mimicked or reversed by experimental modulation of the STAT3-IL6 pathway, but it was partly recapitulated by chemical inhibition of the ARP2/3 complex. Thus, our data suggest that the loss of A-type lamins perturbs the balance between focal adhesions and cytoskeletal tension. This imbalance may contribute to mechanosensing defects observed in certain laminopathies.

Self-etching adhesive on intact enamel, with and without pre-etching.

PubMed

Devarasa, G M; Subba Reddy, V V; Chaitra, N L; Swarna, Y M

2012-05-01

Bond strengths of composite resin to enamel using self-etch adhesive (SEA) Clearfil SE bond system on intact enamel and enamel pre-etched with phosphoric acid were compared. The objective was to determine if the pre-etching would increase the bond strengths of the SEA systems to intact enamel and to evaluate the effect of pre-etching on bond formation of self-etch adhesives on intact enamel. Labial surfaces of 40 caries free permanent upper central and lateral incisors were cleaned, sectioned of their roots. All specimens were mounted on acrylic block and divided randomly into four groups. In two groups the application of self-etch adhesive, Clearfil SE bond was carried as per manufacturer's instructions, composite cylinders were built, whereas in the other two groups, 37% phosphoric acid etching was done before the application of self-etching adhesives. Then the resin tags were analyzed using scanning electron microscope and shear bond strength was measured using Instron universal testing machine. When phosphoric acid was used, there was significant increase in the depth of penetration of resin tags and in the Shear Bond Strength of composite to enamel. The results indicate that out of both treatment groups, pre-etching the intact enamel with 37% phosphoric acid resulted in formation of longer resin tags and higher depth of penetration of resin tags of the Clearfil SE bond, and attaining higher bond strength of the Clearfil SE bond to intact enamel. Copyright © 2011 Wiley Periodicals, Inc.

Streptococcus mutans forms xylitol-resistant biofilm on excess adhesive flash in novel ex-vivo orthodontic bracket model.

PubMed

Ho, Cindy S F; Ming, Yue; Foong, Kelvin W C; Rosa, Vinicius; Thuyen, Truong; Seneviratne, Chaminda J

2017-04-01

During orthodontic bonding procedures, excess adhesive is invariably left on the tooth surface at the interface between the bracket and the enamel junction; it is called excess adhesive flash (EAF). We comparatively evaluated the biofilm formation of Streptococcus mutans on EAF produced by 2 adhesives and examined the therapeutic efficacy of xylitol on S mutans formed on EAF. First, we investigated the biofilm formation of S mutans on 3 orthodontic bracket types: stainless steel preadjusted edgewise, ceramic preadjusted edgewise, and stainless steel self-ligating. Subsequently, tooth-colored Transbond XT (3M Unitek, Monrovia, Calif) and green Grengloo (Ormco, Glendora, Calif) adhesives were used for bonding ceramic brackets to extracted teeth. S mutans biofilms on EAF produced by the adhesives were studied using the crystal violet assay and scanning electron microscopy. Surface roughness and surface energy of the EAF were examined. The therapeutic efficacies of different concentrations of xylitol were tested on S mutans biofilms. Significantly higher biofilms were formed on the ceramic preadjusted edgewise brackets (P = 0.003). Transbond XT had significantly higher S mutans biofilms compared with Grengloo surfaces (P = 0.007). There was no significant difference in surface roughness between Transbond XT and Grengloo surfaces (P >0.05). Surface energy of Transbond XT had a considerably smaller contact angle than did Grengloo, suggesting that Transbond XT is a more hydrophilic material. Xylitol at low concentrations had no significant effect on the reduction of S mutans biofilms on orthodontic adhesives (P = 0.016). Transbond XT orthodontic adhesive resulted in more S mutans biofilm compared with Grengloo adhesive on ceramic brackets. Surface energy seemed to play a more important role than surface roughness for the formation of S mutans biofilm on EAF. Xylitol does not appear to have a therapeutic effect on mature S mutans biofilm. Copyright © 2017 American

Strong composition dependence of adhesive properties of ultraviolet curing adhesives with modified acrylates

NASA Astrophysics Data System (ADS)

Feng, Yefeng; Li, Yandong; Wang, Fupeng; Peng, Cheng; Xu, Zhichao; Hu, Jianbing

2018-05-01

Ultraviolet (UV) curable adhesives have been widely researched in fields of health care and electronic components. UV curing systems with modified acrylic ester prepolymers have been frequently employed. In order to clarify composition dependence of adhesive properties of adhesives containing modified acrylates, in this work, several UV curing adhesives bearing urethane and epoxy acrylates were designed and fabricated. The effects of prepolymer, diluent, feed ratio, initiator and assistant on adhesive performances were investigated. This work might offer a facile route to gain promising high-performance UV curable adhesives with desired adhesive traits through regulating their compositions.

Rapid Loss of Bone Mass and Strength in Mice after Abdominal Irradiation

PubMed Central

Jia, Dan; Gaddy, Dana; Suva, Larry J.; Corry, Peter M.

2011-01-01

Localized irradiation is a common treatment modality for malignancies in the pelvic-abdominal cavity. We report here on the changes in bone mass and strength in mice 7–14 days after abdominal irradiation. Male C57BL/6 mice of 10–12 weeks of age were given a single-dose (0, 5, 10, 15 or 20 Gy) or fractionated (3 Gy × 2 per day × 7.5 days) X rays to the abdomen and monitored daily for up to 14 days. A decrease in the serum bone formation marker and ex vivo osteoblast differentiation was detected 7 days after a single dose of radiation, with little change in the serum bone resorption marker and ex vivo osteoclast formation. A single dose of radiation elicited a loss of bone mineral density (BMD) within 14 days of irradiation. The BMD loss was up to 4.1% in the whole skeleton, 7.3% in tibia, and 7.7% in the femur. Fractionated abdominal irradiation induced similar extents of BMD loss 10 days after the last fraction: 6.2% in the whole skeleton, 5.1% in tibia, and 13.8% in the femur. The loss of BMD was dependent on radiation dose and was more profound in the trabecula-rich regions of the long bones. Moreover, BMD loss in the total skeleton and the femurs progressed with time. Peak load and stiffness in the mid-shaft tibia from irradiated mice were 11.2–14.2% and 11.5–25.0% lower, respectively, than sham controls tested 7 days after a single-dose abdominal irradiation. Our data demonstrate that abdominal irradiation induces a rapid loss of BMD in the mouse skeleton. These effects are bone type- and region-specific but are independent of radiation fractionation. The radiation-induced abscopal damage to the skeleton is manifested by the deterioration of biomechanical properties of the affected bone. PMID:21859327

Tumor-environment biomimetics delay peritoneal metastasis formation by deceiving and redirecting disseminated cancer cells.

PubMed

De Vlieghere, Elly; Gremonprez, Félix; Verset, Laurine; Mariën, Lore; Jones, Christopher J; De Craene, Bram; Berx, Geert; Descamps, Benedicte; Vanhove, Christian; Remon, Jean-Paul; Ceelen, Wim; Demetter, Pieter; Bracke, Marc; De Geest, Bruno G; De Wever, Olivier

2015-06-01

Peritoneal metastasis is life threatening and is the result of an extensive communication between disseminated cancer cells, mesothelial cells and cancer-associated fibroblasts (CAF). CAFs secrete extracellular matrix (ECM) proteins creating a receptive environment for peritoneal implantation. Considering cancer as an ecosystem may provide opportunities to exploit CAFs to create biomimetic traps to deceive and redirect cancer cells. We have designed microparticles (MP) containing a CAF-derived ECM-surface that is intended to compete with natural niches. CAFs were encapsulated in alginate/gelatine beads (500-750 μm in diameter) functionalised with a polyelectrolyte coating (MP[CAF]). The encapsulated CAFs remain viable and metabolically active (≥35 days), when permanently encapsulated. CAF-derived ECM proteins are retained by the non-biodegradable coating. Adhesion experiments mimicking the environment of the peritoneal cavity show the selective capture of floating cancer cells from different tumor origins by MP[CAF] compared to control MP. MP[CAF] are distributed throughout the abdominal cavity without attachment to intestinal organs and without signs of inflammatory reaction. Intraperitoneal delivery of MP[CAF] and sequential removal redirects cancer cell adhesion from the surgical wound to the MP[CAF], delays peritoneal metastasis formation and prolongs animal survival. Our experiments suggest the use of a biomimetic trap based on tumor-environment interactions to delay peritoneal metastasis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Tunable denture adhesives using biomimetic principles for enhanced tissue adhesion in moist environments.

PubMed

Gill, Simrone K; Roohpour, Nima; Topham, Paul D; Tighe, Brian J

2017-11-01

Nature provides many interesting examples of adhesive strategies. Of particular note, the protein glue secreted by marine mussels delivers high adhesion in wet and dynamic environments owing to existence of catechol moieties. As such, this study focuses on denture fixatives, where a non-zinc-containing commercial-based formulation has been judiciously modified by a biomimetic catechol-inspired polymer, poly(3,4-dihydroxystyrene/styrene-alt-maleic acid) in a quest to modulate adhesive performance. In vitro studies, in a lap-shear configuration, revealed that the catechol-modified components were able to enhance adhesion to both the denture base and hydrated, functional oral tissue mimic, with the resulting mode of failure prominently being adhesive rather than cohesive. These characteristics are desirable in prosthodontic fixative applications, for which temporary adhesion must be maintained, with ultimately an adhesive failure from the mucosal tissue surface preferred. These insights provide an experimental platform in the design of future biomimetic adhesive systems. Mussel adhesive proteins have proven to be promising biomimetic adhesive candidates for soft tissues and here for the first time we have adapted marine adhesive technology into a denture fixative application. Importantly, we have incorporated a soft tissue mimic in our in vitro adhesion technique that more closely resembles the oral mucosa than previously studied substrates. The novel biomimetic-modified adhesives showed the ability to score the highest adhesive bonding out of all the formulations included in this study, across all moisture levels. This paper will be of major interest to the Acta Biomaterialia readership since the study has illustrated the potential of biomimetic principles in the design of effective prosthodontic tissue adhesives in a series of purpose-designed in vitro experiments in the context of the challenging features of the oral environment. Copyright © 2017 Acta Materialia

Abdominal wall sinus due to impacting gallstone during laparoscopic cholecystectomy: an unusual complication.

PubMed

Pavlidis, T E; Papaziogas, B T; Koutelidakis, I M; Papaziogas, T B

2002-02-01

During laparoscopic cholecystectomy, perforation of the gallbladder can occurs in < or = 20% of cases, while gallstone spillage occurs in < or = 6% of cases. In most cases, there are no consequences. Gallstones can be lost in the abdominal wall as well as the abdomen during extraction of the gallbladder. The fate of such lost gallstones, which can lead to the formation of an abscess, an abdominal wall mass, or a persistent sinus, has not been studied adequately. Herein we report the case of a persistent sinus of the abdominal wall after an emergent laparoscopic cholecystectomy in an 82-year-old woman with gangrenous cholecystitis and perforation of the friable wall in association with an empyema of the gallbladder. The culture of the obtained pus was positive for Escherichia coli. After a small leak of dirty fluid from the wound of the epigastric port site of 4 months' duration, surgical exploration under local anesthesia revealed that the sinus was caused by spilled gallstones impacting into the abdominal wall between the posterior sheath and left rectus abdominalis muscle. The removal of the stones resulted in complete healing. Long-term complications after laparoscopic cholecystectomy involving the abdominal wall are rare but important possible consequences that could be avoided.

Surface pretreatments for medical application of adhesion

PubMed Central

Erli, Hans J; Marx, Rudolf; Paar, Othmar; Niethard, Fritz U; Weber, Michael; Wirtz, Dieter C

2003-01-01

Medical implants and prostheses (artificial hips, tendono- and ligament plasties) usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m). This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body. PMID:14561228

[Graft Pseudoaneurysm after Ascending to Abdominal Aorta Bypass for Atypical Coarctation Due to Aortitis Syndrome;Report of a Case].

PubMed

Yada, Masashi; Yamanaka, Kazuo; Miwa, Senri; Hirose, Keiichi; Sakaguchi, Hisashi; Yoshida, Yukiyo; Onga, Youhei; Tara, Yuichi

2017-05-01