Absence Of Adhesion Research Articles

Barrier methods used to prevent pelvic adhesions in videolaparoscopy: experimental study in female rabbits

This study was designed to evaluate the effectiveness of barrier methods to prevent adhesions in videolaparoscopy, comparing the use of Surgicel(®) and Interceed(®) with the control group. We performed a controlled, randomized study in healthy adult female rabbits Oryctolagus cuniculu, inducing adhesions in the abdominal wall by resection of a peritoneal fragment and cauterization. In the control group, surgery was performed, and the other group was randomized to the use of the barrier method. After 21 days, videolaparoscopy was repeated, and the presence or absence of adhesions and their score were verified by performing biopsies of the surgical site in all groups. No statistical differences were found in the results on adhesion formation and adhesions score among the three groups. In the control group, there were 54.5% cases of adhesion formation; the median score of adhesions was 6 (range, 3-10). In the Surgicel(®) group, there were 45.5% cases of adhesion formation; median score of adhesions was 6 (range, 4-10). In the Interceed(®) group, there were 45.5% cases of adhesion formation; median score of adhesions was 5 (range, 3-11). No difference was found using barrier methods, Surgicel(®), and Interceed(®) for preventing adhesion formation in videolaparoscopy.

Current review of adhesive capsulitis

Adhesive capsulitis, also known as frozen shoulder, is a common condition involving scapulohumeral pain and loss of motion. This condition was termed “peri-arthritis scapulohumerale” by Duplay in 1896. 36 Duplay S. De la periarthrite scapulohumerale. Rev Frat D Trav De Med. 1896; 53: 226 Google Scholar Codman, 29 Codman EA. The shoulder: rupture of the supraspinatus tendon and other lesions in or about the subacromial bursa. Boston, MA; Thomas Todd Co.; 1934. Google Scholar in 1934, characterized the diagnosis of “frozen shoulder” as a condition characterized by pain and reduced range of motion in the affected shoulder. Neviaser, 75 Neviaser J.S. Adhesive capsulitis of the shoulder: a study of the pathological findings in periarthritis of the shoulder. J Bone Joint Surg Am. 1945; 27: 211-222 Google Scholar in the pre-arthroscopic era, subsequently used the term “adhesive capsulitis” to describe the findings of chronic inflammation and fibrosis of the joint capsule, although arthroscopic examination would support the term “fibrotic capsulitis” with the absence of adhesions. The current consensus definition of the American Shoulder and Elbow Surgeons is “a condition of uncertain etiology characterized by significant restriction of both active and passive shoulder motion that occurs in the absence of a known intrinsic shoulder disorder.” 69 Matsen FA, Fu FH, Hawkins RJ. The shoulder: a balance of mobility and stability. Rosemont, IL: American Academy of Orthopaedic Surgeons; 1993. Google Scholar , 113 Zuckerman J. Cuomo F. Rokito S. Definition and classification of frozen shoulder: a consensus approach. J Shoulder Elbow Surg. 1994; 3: S72 Google Scholar

Review Article: Adhesion Prevention and Reduction: Current Status and Future Recommendations of a Multinational Interdisciplinary Consensus Conference

Adhesions can be found after virtually every abdominopelvic operation performed through standard laparotomy as well as by laparoscopic approaches. Adhesions can be completely asymptomatic or can cause significant morbidity and mortality including strangulation, obstruction, and necrosis of bowel loops and/or infertility and organ injury during repeat abdominal surgery. Perhaps because of the multifactorial nature of adhesion development, prevention has been very limited. Three anti-adhesion products are commercially available, none of which has been universally accepted as a panacea. Part of the obstacles with adhesion management is the lack of an objective clinically relevant classification to allow their study. Because a single band can cause a life-threatening bowel obstruction, whereas extensive dense intra-abdominal adhesions may be asymptomatic, neither the mere presence or absence of adhesions nor their extent if present is totally adequate endpoints. Adhesions are a major health care burden, and their reduction is a significant unmet need in surgical therapeutics facing all surgeons. Of all the parameters assessing adhesions currently available, the authors believe that adhesion incidence (presence or absence) is the most relevant endpoint with a direct clinical implication. The authors endorse the development of a validated, clinically relevant scale to assess intra-abdominal adhesions. Given the present limitation of objective assessment of adhesions and prediction of their clinical effect, the authors also advocate, when appropriate, the use of one of the Food and Drug Administration-approved adhesion barriers. Further research is required to develop safe and effective anti-adhesion methods as well as better assessment tools for their efficacy.

Determination of native (wood derived) formaldehyde by the desiccator method in particleboards generated during panel production

AbstractHot-pressing wood, particularly in the production of wood composites, generates significant “native” (wood-based) formaldehyde (FA), even in the absence of adhesive. The level of native FA relates directly to the time and temperature of hot-pressing. This native FA dissipates in a relatively short time and is not part of the long-term FA emission issue commonly associated with hydrolyzing urea-formaldehyde bonds. This paper demonstrates that the common desiccator/chromotropic acid method is very specific for FA and is not influenced by other volatile compounds set free from wood during hot-pressing. Furthermore, it is shown that particleboard produces native FA at high levels even in the absence of adhesives or in the presence of one type of no-added formaldehyde (NAF) adhesive. Soy-based adhesives suppress native FA emission and provide low FA emission levels in both the short and long term. This study highlights an often overlooked aspect that should be considered for emission testing: standardizing the time and conditions employed immediately after pressing and prior to the onset of emissions testing. Addressing this issue in more detail would improve the reliability of correlation between data obtained by rapid process monitoring methods and emission measurements in large chambers.

ErbB2 requires integrin α5 for anoikis resistance via Src regulation of receptor activity in human mammary epithelial cells

ErbB2, a receptor tyrosine kinase highly expressed in many tumors, is known to inhibit apoptotic signals. Overexpression of ErbB2 causes anoikis resistance that contributes to luminal filling in three-dimensional mammary epithelial acinar structures in vitro. Given that integrins and growth factor receptors are highly interdependent for function, we examined the role of integrin subunits in ErbB2-mediated survival signaling. Here, we show that MCF-10A cells overexpressing ErbB2 upregulate integrin alpha5 via the MAP-kinase pathway in three-dimensional acini and found elevated integrin alpha5 levels associated with ErbB2 status in human breast cancer. Integrin alpha5 is required for ErbB2-mediated anoikis resistance and for optimal ErbB2 signaling to the Mek-Erk-Bim axis as depletion of integrin alpha5 reverses anoikis resistance and Bim inhibition. Integrin alpha5 is required for full activation of ErbB2 tyrosine phosphorylation on Y877 and ErbB2 phosphorylation is associated with increased activity of Src in the absence of adhesion. Indeed, we show that blocking elevated Src activity during cell detachment reverses ErbB2-mediated survival and Bim repression. Thus, integrin alpha5 serves as a key mediator of Src and ErbB2-survival signaling in low adhesion states, which are necessary to block the pro-anoikis mediator Bim, and we suggest that this pathway represents a potential novel therapeutic target in ErbB2-positive tumors.

Redox regulation of anoikis resistance of metastatic prostate cancer cells: key role for Src and EGFR-mediated pro-survival signals

Resistance to detachment-induced apoptosis, a process commonly referred as anoikis, is emerging as a hallmark of metastatic malignancies, mainly because it can ensure anchorage-independent growth and survival during organ colonization. Besides, a sustained oxidative stress has been associated with several steps of carcinogenesis, including transformation and achievement of a motile mesenchymal phenotype. Here, we demonstrate that metastatic prostate carcinoma cells, undergoing a constitutive deregulated production of reactive oxygen species due to sustained activation of 5-lipoxygenase, lack suicidal pathways in response to lack of matrix contact. These amplified and persistent redox signals in PC3 cells leads to maintenance of Src oxidation and activation in the absence of adhesion, thereby sustaining a ligand-independent phosphorylation of epidermal growth factor receptor. This leads to chronic activation of pro-survival signals, culminating in degradation of the pro-apoptotic protein Bim, thereby promoting cell survival even in the absence of proper adhesion. Anoikis sensitivity of metastatic cells is restored with antioxidant intervention or genetic manipulation of the redox-mediated pro-survival pathway, as well as exposure to a pro-oxidant environment strongly increases anoikis resistance in non-transformed prostate epithelial cells. Hence, our results allow new insight into the aetiology of the molecular mechanisms granting anoikis resistance of metastatic cancers, opening new avenues to pharmacological intervention for antioxidant-sensitive invasive tumours.

Laparoscopic liver resection facilitates salvage liver transplantation for hepatocellular carcinoma

In patients with hepatocellular carcinoma (HCC), a previous liver resection (LR) may compromise subsequent liver transplantation (LT) by creating adhesions and increasing surgical difficulty. Initial laparoscopic LR (LLR) may reduce such technical consequences, but its effect on subsequent LT has not been reported. We report the operative results of LT after laparoscopic or open liver resection (OLR). Twenty-four LT were performed, 12 following prior LLR and 12 following prior OLR. The LT was performed using preservation of the inferior vein cava. Indication for the LT was recurrent HCC in 19 cases (salvage LT), while five patients were listed for LT and underwent resection as a neoadjuvant procedure (bridge resection). In the LLR group, absence of adhesions was associated with straightforward access to the liver in all cases. In the OLR group, 11 patients required long and hemorrhagic dissection. Median durations of the hepatectomy phase and whole LT were 2.5 and 6.2 h, and 4.5 and 8.3 h in the LLR and OLR groups, respectively (P < 0.05). Median blood loss was 1200 ml and 2300 ml in the LLR and OLR groups, respectively (P < 0.05). Median transfusions of hepatectomy phase and whole LT were 0 and 3 U, and 2 and 6 U, respectively (P < 0.05). There were no postoperative deaths. In our study, LLR facilitated the LT procedure as compared with OLR in terms of reduced operative time, blood loss and transfusion requirements. We conclude that LLR should be preferred over OLR when feasible in potential transplant candidates.

Effect of adhesion on the status of corneal tissue during in vitro culturing

Newt and rat cornea with and without the corneal limbus was cultured under conditions of adhesion to a substrate (stationary culturing) and in the absence of adhesion (roller culturing). It was found that the contact of the tissue with the substrate play the key role in the transduction of the regulatory signal that ensures the maintenance of cornea viability and affects proliferation and migration of cornea cells.

Formaldehyde‐free aminoresin wood adhesives based on dimethoxyethanal

AbstractAminoresin precursors prepared by the addition of a new, colorless, nonvolatile and nontoxic aldehyde, dimethoxyethanal (DME), to melamine or urea gave resins for boards that were able to harden, however they were underperforming because of the lower reactivity of DME in relation to formaldehyde. Melamine and urea reacts with one and two (melamine up to three) molecules of DME to form M‐DME and U‐DME (called DU), but the subsequent cross‐linking reaction to form bridges does not occur unless the reaction is catalyzed during resin preparation by the addition of glyoxylic acid. Such bridges between two melamine molecules form only up to the formation of dimers and no more. The use of glyoxylic acid during the reaction has allowed the formation of different oligomers formed by both aldol condensation and condensation of melamine and glyoxylic acid with two molecules of melamine to form dimers. These were observed by 13C NMR and MALDI‐TOF (matrix‐assisted laser desorption/ionization mass spectroscopy). However, the addition of 20% isocyanate (pMDI) was necessary to satisfy the relevant mechanical strength standards of panels prepared with these resins. pMDI contributed to cross‐linking of M‐DME and DU by its reaction to form urethane bridges according to reactions already described. The adhesive resins so formed had excellent performance and were colorless, and they produced boards that well satisfied the requirements of the relevant standards for interior panels. Formaldehyde emission was down to what would be expected obtained by just heating the wood chips in absence of adhesives. The panels emission was sufficiently low to even satisfy the most severe relevant F**** JIS A 5908 Japanese standard. These adhesives are colorless as MUF and UF resins. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Role of erythrocytes in platelet activation during exposure to pathophysiological shear stress

Interaction of von Willebrand factor (VWF) with circulating blood platelets is the initial trigger for thrombosis in an arterial stenosis. Exposure of blood to a high shear stress promotes such interaction. These events have previously been studied in vitro under conditions where the platelets adhere to a VWF‐coated surface. Our approach assesses platelet activation in the absence of adhesion. Whole blood is perfused through polyetheretherketone (PEEK) tubing that includes an artificial stenosis, comprising a short (4 cm) section of narrow‐bore (130 μm) tubing. The pressure differential across the stenosis was measured with a pressure transducer. Platelet activation was evaluated from secretion of [14C]serotonin, and erythrocyte lysis from release of hemoglobin. The pressure drop across the stenosis matched the predictions for laminar flow without turbulence. Platelet activation rose progressively with increasing perfusion rate (2–12 ml/min). We examined the role of erythrocytes in platelet activation by adjusting the hematocrit of the perfused blood. Platelet activation was minimal (mean increment of 1.9% in serotonin secretion at 12 ml/min flow) when the hematocrit was low (30%), but substantial (increment of 15.5%) with a high hematocrit (60%). In contrast, changes in the platelet count did not affect the extent of platelet activation. [Supported by the National Science Foundation.]

Lid margin split in the surgical correction of epiblepharon

To describe the technique of splitting the lid margin combined with the excision of redundant skin and muscle during the surgical correction of epiblepharon and to report its clinical outcome. A combined procedure that included splitting the lid margin to repair lower eyelid epiblepharon was performed on 31 eyes of 19 consecutive patients. Lid margin splitting was performed along the grey line on the medial third or half of the lower eyelid by making a 1 mm-deep incision. Having made a transverse subciliary skin incision and a dissection between the tarsus and the orbicularis oculi muscle, the subcutaneous tissue of the superior edge of the incision was secured to the tarsus with interrupted sutures to evert the cilia. An excision of the redundant skin and orbicularis tissue was made and the skin was closed. The patients were followed for direct inspection of the wound, the split lid margin, the direction of the lashes and the status of the cornea. The mean postoperative follow-up period was 29.4 weeks. Symptoms disappeared in all patients. In 30 eyelids of 19 patients the cilia did not touch the cornea, even in the down-gaze. In one eyelid the cilium touched the medial conjunctiva, but not the cornea. The cosmetic outcome of the lower lid was satisfactory in all cases and the wounds of the split lid margin healed without scarring. To date, there have been no complications such as wound dehiscence, ectropion or eyelid retraction. The lamellar splitting of the lid margin is a beneficial addition to the repair of prominent lower lid epiblepharon, especially on the medial aspect of the eyelid. This simple technique ensures easier eversion of the cilia in epiblepharon repair, without disturbing the posterior lamella or causing unfavourable results.

Evaluation of DualMesh for repair of large hiatus hernia in a porcine model

Prosthetic fascial grafts are frequently used for augmentation of cruroplasty in large hiatus hernia repair to decrease the chances of recurrence. Potential complications such as intraluminal erosion may be related to the constant movement of mesh and diaphragm over the outer surface of the esophagus. This study aimed to evaluate DualMesh for repair of large hiatal defects in a porcine model. In this study, 18 Landrace x large white x Duroc crossbred pigs underwent either primary hiatal repair or tension-free prosthetic repair using DualMesh (80 x 50 mm or 80 x 100 mm). The animals were killed at 3 or 28 weeks for macroscopic and histologic evaluation of the hiatal region and gastroesophageal junction. All grafts had become encapsulated at 28 weeks, and the majority had filmy adhesions only to the visceral aspect. In all models, the esophagus moved freely over the cut edge of the prosthesis. No signs of intraluminal erosion were documented. At histologic examination, significant ingrowth was noted on the porous side of the mesh, whereas no defined mesothelial layer was identified on the capsule of the nonporous side. In this animal model of large hiatus hernia repair, DualMesh showed optimal characteristics in terms of host tissue incorporation on the porous side and absence of adhesions on the visceral side of the prosthesis. The absence of adhesions and intraluminal erosion in this study may provide reassurance to surgeons using mesh at the hiatus.

Fibroepithelial polyps: Preoperative diagnosis may avoid thoracotomy

ative respiratory function (Figure 2). Conversely, preservation of the middle lobe in the absence of the upper and lower lobes may induce torsion. Various factors appear to be associated with lobar torsion, including complete interlobar fissure, absence of adhesions, a narrow middle lobe hilum, and overzealous mobilization of the lobe. In our case, the middle lobe was fixed by adhesions to the chest wall. However, emphysematous changes in the residual middle lobe may be induced owing to volume mismatch in the middle lobe and thoracic cavity during long-term follow-up. In conclusion, preserving the middle lobe after resection of both upper and lower lobes offers advantages to residual respiratory function, compared with results from completion pneumonectomy. References

Right lower lobectomy after right upper lobectomy for multiple metastases in lung cancer of the right lower lobe: Benefit of middle lobe preservation

Clinical Summary A 60-year-old woman with lung cancer underwent right upper lobectomy. The tumor specimen was a well-differentiated adenocarcinoma, pathologic stage IA (T1 N0 M0). Multiple slow-growing nodules were noted in the right lower lobe 4 years postoperatively. Recurrent lesions are generally multiple and disseminated, and additional surgical intervention is not usually indicated. However, no nodules were apparent in other lobes during 1 year of follow-up. The patient was therefore referred to our department for surgical treatment. Routine blood biochemistry and coagulation studies yielded normal results and carcinoembryonic antigen level was 2.6 ng/mL. A chest computed tomographic scan from 4 years earlier showed the primary lung cancer as a solid tumor in the right upper lobe (Figure 1, A), compared with the scan of multiple nodules limited to the right lower lobe for the metastases (Figure 1, B). These multiple tumors showed no uptake on a fluorodeoxyglucose positron emission tomographic scan. Transbronchiolar lung biopsy was not performed owing to patient refusal. No extrathoracic metastatic lesions were identified. Preoperative forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1.0) were 2420 mL and 1510 mL, respectively. We evaluated predicted results of completion pnuemonectomy using perfusion scintigraphy and pulmonary artery obstruction testing. Predicted FVC and FEV1.0 after completion pneumonectomy were 1114 mL and 695 mL, respectively. Obstruction of the right pulmonary artery yielded a pressure of 19 mm Hg. Video-assisted right lower lobectomy was performed, preserving the middle lobe. Adhesion of the lower lobe to the chest wall was easily removed by the thoracoscopic view. The middle lobe was also adherent to the chest wall and helped to prevent middle lobe torsion. On final pathologic examination, the specimen from the lower lobe was characteristic of metastatic adenocarcinoma from the previous lung cancer of the right upper lobe (Figure 1, C and D). Postoperative FVC and FEV1.0 were 1570 mL and 1200 mL, respectively. Perfusion scintigraphy showed 391,199 (21.7%) of 1,801,504 counts for the preserved middle lobe (Figure 2). Respiratory function after right upper and lower lobectomies preserved more than half of the original respiratory function. The postoperative course was uneventful. Chest computed tomographic imaging after 1 year of preservation of the middle lobe showed adequate volume without emphysematous change. After 17 months of follow-up, the patient is doing well with no evidence of disease or requirement for additional oxygen support.

Severe chronic abdominal pain in the absence of adhesions

Management of the patient with chronic severe abdominal pain in the absence of adhesions remains one of the major challenges of the gastroenterologist. Given that extensive investigation will inevitably take place of such individual, the role of the gastroenterologist who is asked to review such a problem, is to identify unusual manifestations of common disorders from new, previously-unidentified causes, and to assess the degree to which somatisation and psychological overlay are exacerbating the problem. Investigations must be targeted against clinically-generated hypotheses rather than to repeat a non-systematic approach. Therapy in the absence of a newly-identified disorder is generally targeted at alleviating rather than removing symptoms, addressing an individual's personal pain and management needs, and avoiding ever more complex and invasive investigations.

P-459: Should ruptured tubal ectopic pregnancies be managed laparoscopically?

P-459: Should ruptured tubal ectopic pregnancies be managed laparoscopically?

The Effect of a Hyaluronic Acid–Based Nasal Pack on Mucosal Healing in a Sheep Model of Sinusitis

A hyaluronic acid-based nasal pack has been shown previously to have a beneficial effect on mucosal healing in a healthy sheep model. However, endoscopic sinus surgery (ESS) usually is performed in the presence of infection and inflammation. The aim of this study was to examine the efficacy of hyaluronic acid-based nasal packing on mucosal healing in a sheep model of chronic sinusitis. A standardized sheep model of chronic sinusitis was used. Full-thickness mucosal injuries were performed under endoscopic guidance with a microdebrider. Adjacent wounds were created between the lateral nasal wall and the ethmoid turbinate. Then, the injuries were either packed with a dissolvable hyaluronic acid-based pack or left unpacked to serve as a control. Serial biopsies of the healing mucosa were performed at days 28, 56, 84, and 112 postsurgery, and the presence or absence of adhesions between the ethmoid turbinate and lateral nasal wall was noted. The biopsy specimens were assessed for reepithelialization and epithelial height using light microscopy, and for reciliation using scanning electron microscopy. There was no significant difference in reepithelialization or relative epithelial height between the packed sides and the control sides at any time point. There was a statistically significant difference in reciliation between the two groups at day 112 but this was not deemed clinically significant. The packing had no significant effect on adhesion formation. In the sheep model of chronic sinusitis, a dissolvable hyaluronic acid-based pack did not have any significant effect on mucosal healing or adhesions formation after ESS, as assessed by examining reepithelialization, epithelial height, reciliation, and the presence of adhesions.

Mechanisms of Single-Walled Carbon Nanotube Probe−Sample Multistability in Tapping Mode AFM Imaging

When using single-walled carbon nanotube (SWNT) probes to create AFM images of SWNT samples in tapping mode, elastic deformations of the probe and sample result in a decrease in the apparent width of the sample. Here we show that there are two major mechanisms for this effect, smooth gliding and snapping, and compare their dynamics to the case when a conventional silicon tip is used to image a bare silicon surface. Using atomistic and continuum simulations, we analyze in detail the shape of the tip-sample interaction potential for three model cases and show that in the absence of adhesion and friction forces, more than two discrete, physically meaningful solutions of the oscillation amplitude are possible when snapping occurs (in contrast to the existence of one attractive and one repulsive solution for conventional silicon AFM tips). We present experimental results indicating that a continuum of amplitude solutions is possible when using SWNT tips and explain this phenomenon with dynamic simulations that explicitly include tip-sample adhesion and friction forces. We also provide simulation results of SWNT tips imaging Si(111)-CH3 surface step edges and Au nanocrystals, which indicate that SWNT probe multistability may be a general phenomenon, not limited to SWNT samples.

Adhesion control of cyclin D1 and p27Kip1 levels is deregulated in melanoma cells through BRAF-MEK-ERK signaling

Mutations in BRAF, a component of extracellular signal-regulated kinases 1 and 2 (ERK) cascade, are frequent in melanoma. It is important to understand how BRAF mutations contribute to malignant traits including anchorage- and growth factor-independence. We have previously shown that efficient activation of ERK in normal human epidermal melanocytes (NHEM) requires both adhesion to the extracellular matrix and growth factors. Mutant V599E BRAF is sufficient to promote ERK activation independent of adhesion and growth factors. Here, we analysed regulation of G1 cell cycle events in NHEM and human melanoma cells. We show that S phase entry in NHEM requires both adhesion and growth factor signaling through the MEK-ERK pathway. This control correlates with induction of cyclin D1 and downregulation of p27Kip1, two key G1 cell cycle events. In melanoma cells expressing V599E BRAF, cyclin D1 was constitutively expressed independent of adhesion but dependent upon MEK activation and nuclear accumulation of ERK. Reduction of cyclin D1 levels by RNA interference inhibited S phase entry in melanoma cells. Importantly, expression of V599E BRAF in NHEM was sufficient to promote cyclin D1 promoter activity in the absence of adhesion. Additionally, p27Kip1 levels were downregulated in V599E BRAF-expressing melanoma cells and active BRAF was sufficient to downregulate p27Kip1 in serum-starved NHEM. Thus, adhesion-growth factor cooperation, leading to efficient activation of ERK, regulates cyclin D1 and p27Kip1 levels in human melanocytes and mutant BRAF overrides adhesion-growth factor control of these two G1 cell cycle proteins in melanomas. These findings provide important insight into how BRAF mutations contribute to aberrant human melanocyte proliferation.

Adhesion prediction on metal thermal spray coatings

Bonding prediction (presence or absence of adhesion) of metal thermal spray coatings is of theoretical and practical interest. The present paper introduces a simple method for estimating the adhesion performance of metal thermal spray coatings. To improve the conditions expected in the case of poor adhesion, the proposed method can also provide and anticipate suitable types of metal thermal spray coatings to overcome the problem. The expansion coefficient is inventively used as a quality indication for bonding performance of metal thermal spray coatings.