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  1. Abdominal Adhesions

    MedlinePlus

    ... Abdominal Adhesions 1 Ward BC, Panitch A. Abdominal adhesions: current and novel therapies. Journal of Surgical Research. 2011;165(1):91– ... are abdominal adhesions and intestinal obstructions ... generally do not require treatment. Surgery is the only way to treat abdominal ...

  2. Abdominal Adhesions

    MedlinePlus

    ... Adhesions 1 Ward BC, Panitch A. Abdominal adhesions: current and novel therapies. Journal of Surgical Research. 2011;165(1):91–111. Seek Help for ... and how to participate, visit the NIH Clinical Research Trials and You website ... Foundation for Functional Gastrointestinal Disorders 700 West Virginia ...

  3. Effects of Intraperitoneal Administration of Simvastatin in Prevention of Postoperative Intra-abdominal Adhesion Formation in Animal Model of Rat

    PubMed Central

    Javaherzadeh, Mojtaba; Shekarchizadeh, Ali; Kafaei, Marjan; Mirafshrieh, Abass; Mosaffa, Nariman; Sabet, Babak

    2016-01-01

    Objective: To determine the preventive effects of local administration of simvastatin for postoperative intra-abdominal adhesion formation in animal model of rat.  Methods: In this experimental study, 32 Wistar albino rats as the animal model of intra-abdominal adhesion formation were included. Adhesions were induced in all the animals via abrasion of the peritoneal and intestinal surface during laparotomy. Afterwards, the rats were randomly assigned to receive simvastatin (30 mg/kg body weight) as a single intraperitoneal dose at the time of laparotomy (n=16) or normal saline in same volume at the same time (n=16). At the day 21, animals were euthanized and the adhesions were quantified clinically (via repeated laparotomy) and pathologically and compared between the two groups. Results: The baseline characteristics of the animals were comparable between two study groups. Clinically, in simvastatin group, 10 rats (62.5%) did not develop any adhesion and 6 (37.5%) had first-grade adhesion; whereas in the control group, 11 (68.8%) rats had first- and 5 (31.2%) had second-grade adhesions (p<0.001). Pathologically, in simvastatin group, 6 rats (37.5%) had first-grade adhesion, while in control group, 11 rats (68.8%) had first- and 5 (31.2%) had second-grade adhesions (p<0.001). Conclusion: Our findings suggest that intraperitoneal administration of simvastatin is an effective method for prevention of postoperative intra-abdominal adhesion formation in animal model of rat.   PMID:27540550

  4. Effect of carbodiimide-derivatized hyaluronic acid gelatin on preventing postsurgical intra-abdominal adhesion formation and promoting healing in a rat model.

    PubMed

    Yuan, Fang; Lin, Long-Xiang; Zhang, Hui-Hui; Huang, Dan; Sun, Yu-Long

    2016-05-01

    Adhesions often occur after abdominal surgery. It could cause chronic pelvic pain, intestinal obstruction, and infertility. A hydrogel biomaterial, carbodiimide-derivatized hyaluronic acid gelatin (cd-HA gelatin), has been successfully used to reduce adhesion formation after flexor tendon grafting. This study investigated the efficacy of cd-HA gelatin in preventing postsurgical peritoneal adhesions in a rat model. The surgical traumas were created on the underlying muscle of the abdominal wall and the serosal layer of the cecum. The wounds were covered with or without cd-HA gelatin. Animals were euthanized at day 14 after surgery. Adhesion formation was assessed with adhesion degree and adhesion breaking strength. The healing of abdominal wall was evaluated with biomechanical testing and histological analysis. The adhesions occurred in all rats (n = 12) without cd-HA gelatin treatment. The application of cd-HA gelatin significantly reduced the adhesion rate from 100% to 58%. The decrease of adhesion breaking strength also manifested that cd-HA gelatin could reduce postsurgical intra-abdominal adhesion formation. Moreover, it was found that cd-HA gelatin was a safe material and could promote tissue healing. The cd-HA gelatin hydrogel could reduce the formation of intra-abdominal adhesions without adversely effects on wound healing. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1175-1181, 2016. PMID:26749008

  5. Peritoneal Response to Abdominal Surgery: The Role of Equine Abdominal Adhesions and Current Prophylactic Strategies

    PubMed Central

    Alonso, Juliana de Moura; Alves, Ana Liz Garcia; Watanabe, Marcos Jun; Rodrigues, Celso Antonio; Hussni, Carlos Alberto

    2014-01-01

    Intra-abdominal adhesions constitute a significant clinical and surgical problem that can lead to complications such as pain and bowel occlusion or subocclusion. These adhesions are frustrating and potentially fatal, representing a major postoperative complication in abdominal surgery. It is estimated that 32% of horses undergoing laparotomy will present clinical symptoms due to adhesions, but the true prevalence is not known because a large proportion of animals with postoperative recurrent colics are medically treated or submitted to euthanasia without necropsy. Adhesions are highly cellular, vascularized, dynamic structures that are influenced by complex signaling mechanisms. Understanding their pathogenesis could assist in applying better therapeutic strategies and in developing more effective antiadhesion products. Currently, there are no definitive strategies that prevent adhesion formation, and it is difficult to interpret the results of existing studies due to nonstandardization of an induction model and evaluation of their severity. The best clinical results have been obtained from using minimally traumatic surgical techniques, anti-inflammatory agents, antimicrobials, anticoagulants, and mechanical separation of serosal surfaces by viscous intraperitoneal solutions or physical barriers. This paper aims to review adhesion formation pathogenesis, guide the understanding of major products and drugs used to inhibit adhesion formation, and address their effectiveness in the equine species. PMID:24587939

  6. Inhibition of cyclooxygenase-2 prevents intra-abdominal adhesions by decreasing activity of peritoneal fibroblasts

    PubMed Central

    Wei, Guangbing; Chen, Xin; Wang, Guanghui; Jia, Pengbo; Xu, Qinhong; Ping, Gaofeng; Wang, Kang; Li, Xuqi

    2015-01-01

    Background Postoperative intra-abdominal adhesions are common complications after abdominal surgery. The exact molecular mechanisms that are responsible for these complications remain unclear, and there are no effective methods for preventing adhesion formation or reformation. The aim of the study reported here was to investigate the preventive effects and underlying potential molecular mechanisms of selective cyclooxygenase-2 (COX-2) inhibitors in a rodent model of postoperative intra-abdominal adhesions. Materials and methods The expression of COX-2 in postoperative intra-abdominal adhe-sions and normal peritoneal tissue was examined by immunohistochemistry and Western blot analysis. Assays were performed to elucidate the effect of COX-2 inhibition on hypoxia-induced fibroblast activity in vitro and on intra-abdominal adhesion formation in vivo. Results Hypoxia-induced COX-2 expression in peritoneal fibroblasts was increased in postoperative intra-abdominal adhesions. Inhibition of COX-2 attenuated the activating effect of hypoxia on normal peritoneal fibroblasts in vitro. Data indicate that selective COX-2 inhibitor prevents in vivo intra-abdominal adhesion by inhibition of basic fibroblast growth factor and transforming growth factor-beta expression, but not through an antiangiogenic mechanism. Furthermore, using selective COX-2 inhibitors to prevent intra-abdominal adhesions did not adversely affect the weight, bowel motility, or healing of intestinal anastomoses in a rat model. Conclusion These results show that hypoxia-induced COX-2 expression in peritoneal fibroblasts is involved in the formation of intra-abdominal adhesions. Inhibition of COX-2 prevents postoperative intra-abdominal adhesions through suppression of inflammatory cytokines. PMID:26109851

  7. Preventing postoperative abdominal adhesions in a rat model with PEG-PCL-PEG hydrogel

    PubMed Central

    Yang, Bing; Gong, ChangYang; Zhao, Xia; Zhou, ShengTao; Li, ZhengYu; Qi, XiaoRong; Zhong, Qian; Luo, Feng; Qian, ZhiYong

    2012-01-01

    Background Poly (ethylene glycol)-poly (ɛ-caprolactone)-poly (ethylene glycol) (PEG-PCL-PEG, PECE) hydrogel has been demonstrated to be biocompatible and thermosensitive. In this study, its potential efficacy and mechanisms of preventing postsurgical abdominal adhesions were investigated. Results PECE hydrogel was transformed into gel state from sol state in less than 20 seconds at 37°C. None of the animals treated with the hydrogel (n = 15) developed adhesions. In contrast, all untreated animals (n = 15) had adhesions that could only be separated by sharp dissection (P < 0.001). The hydrogel adhered to the peritoneal wounds, gradually disappeared from the wounds within 7 days, and transformed into viscous fluid, being completely absorbed within 12 days. The parietal and visceral peritoneum were remesothelialized in about 5 and 9 days, respectively. The hydrogel prevented the formation of fibrinous adhesion and the invasion of fibroblasts. Also, along with the hydrogel degradation, a temporary inflammatory cell barrier was formed which could effectively delay the invasion of fibroblasts during the critical period of mesothelial regeneration. Conclusion The results suggested that PECE hydrogel could effectively prevent postsurgical intra-abdominal adhesions, which possibly result from the prevention of the fibrinous adhesion formation and the fibroblast invasion, the promotion of the remesothelialization, and the hydroflotation effect. PMID:22346350

  8. Postoperative Adhesion Development Following Cesarean and Open Intra-Abdominal Gynecological Operations

    PubMed Central

    Awonuga, Awoniyi O.; Fletcher, Nicole M.; Saed, Ghassan M.; Diamond, Michael P.

    2011-01-01

    In this review, we discuss the pathophysiology of adhesion development, the impact of physiological changes associated with pregnancy on markers of adhesion development, and the clinical implications of adhesion development following cesarean delivery (CD). Although peritoneal adhesions develop after the overwhelming majority of intra-abdominal and pelvic surgery, there is evidence in the literature that suggests that patients having CD may develop adhesions less frequently. However, adhesions continue to be a concern after CD, and are likely significant, albeit on average less than after gynecological operations, but with potential to cause significant delay in the delivery of the baby with serious, lifelong consequences. Appreciation of the pathophysiology of adhesion development described herein should allow a more informed approach to the rapidly evolving field of intra-abdominal adhesions and should serve as a reference for an evidence-based approach to consideration for the prevention and treatment of adhesions. PMID:21775773

  9. [Impact of abdominal cavity open EHF irradiation on activity of adhesive process in peritonitis].

    PubMed

    Boĭko, V V; Ivanova, Iu V; Gamidov, A N; Andreeshchev, S A

    2015-01-01

    In experiment on 45 rats a purulent peritonitis was simulated. There was established, that on background of a standard therapy for peritonitis application of abdominal cavity open irradiation of extreme high frequency (EHF) have promoted rapid stabilization of the lipid metabolism indices and the blood coagulation system, the reduction of intensity of lipids peroxidal oxidation processes and severity of systemic inflammatory reaction. Under the influence of complex treatment the severity of adhesive process was reduced in 5.4 times, comparing with such in animals, to whom a standard treatment was conducted only. The revealed pathogenetic aspects of the adhesions formation witnesses the expediency to add EHF irradiation to complex therapy of peritonitis. PMID:25842685

  10. Adhesion

    MedlinePlus

    ... adhesions Ovarian cyst References Munireddy S, Kavalukas SL, Barbul A. Intra-abdominal healing: gastrointestinal tract and adhesions. Surg Clin N Am Kulaylat MN, Dayton, MT. Surgical complications. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, ...

  11. Effect of Hypericum perforatum on intraperitoneal adhesion formation in rats

    PubMed Central

    Hızlı, Fatih; Köşüş, Aydın; Yılmaz, Saynur; Köşüş, Nermin; Haltaş, Hacer; Dede, Hülya; Kafalı, Hasan

    2013-01-01

    Introduction The aim of this study was to evaluate the efficacy of Hypericum perforatum for prevention of adhesion formation in rats. Material and methods Twenty-four female wistar rats underwent left uterine horn adhesion model. Rats were randomised into 4 groups. Group 1 (Control): Closure of abdominal incision without any agent administration. Group 2: Closure of incision after administration of intraperitoneal (i.p.) Ringer's lactate solution. Group 3: Closure of incision after administration of i.p. olive oil (diluent of H. perforatum). Group 4: Hypericum perforatum extract (Ecodab®) was administered i.p. before the closure of incision. Fourteen days later, relaparatomy was performed and surgical adhesion scores, inflammation and fibrosis scores were noted. Groups were compared according to these scores. Results There was statistical significant difference between ringer's lactate group and olive oil group according to surgical adhesion score (p = 0.009). However, groups were not different according to inflammation and fibrosis scores (p > 0.05). Conclusions Despite antiinflammatory, antioxidants and antimicrobial properties of H. perforatum, our results revealed no positive effect of H. perforatum on the prevention of intraperitoneal adhesion formation. PMID:24904678

  12. Adhesions to Mesh after Ventral Hernia Mesh Repair Are Detected by MRI but Are Not a Cause of Long Term Chronic Abdominal Pain

    PubMed Central

    Langbach, Odd; Holmedal, Stein Harald; Grandal, Ole Jacob

    2016-01-01

    Aim. The aim of the present study was to perform MRI in patients after ventral hernia mesh repair, in order to evaluate MRI's ability to detect intra-abdominal adhesions. Materials and Methods. Single-center long term follow-up study of 155 patients operated for ventral hernia with laparoscopic (LVHR) or open mesh repair (OVHR), including analyzing medical records, clinical investigation with patient-reported pain (VAS-scale), and MRI. MRI was performed in 124 patients: 114 patients (74%) after follow-up, and 10 patients referred for late complaints after ventral mesh repair. To verify the MRI-diagnosis of adhesions, laparoscopy was performed after MRI in a cohort of 20 patients. Results. MRI detected adhesions between bowel and abdominal wall/mesh in 60% of the patients and mesh shrinkage in 20–50%. Adhesions were demonstrated to all types of meshes after both LVHR and OVHR with a sensitivity of 70%, specificity of 75%, positive predictive value of 78%, and negative predictive value of 67%. Independent predictors for formation of adhesions were mesh area as determined by MRI and Charlson index. The presence of adhesions was not associated with more pain. Conclusion. MRI can detect adhesions between bowel and abdominal wall in a fair reliable way. Adhesions are formed both after open and laparoscopic hernia mesh repair and are not associated with chronic pain. PMID:26819601

  13. Adhesions to Mesh after Ventral Hernia Mesh Repair Are Detected by MRI but Are Not a Cause of Long Term Chronic Abdominal Pain.

    PubMed

    Langbach, Odd; Holmedal, Stein Harald; Grandal, Ole Jacob; Røkke, Ola

    2016-01-01

    Aim. The aim of the present study was to perform MRI in patients after ventral hernia mesh repair, in order to evaluate MRI's ability to detect intra-abdominal adhesions. Materials and Methods. Single-center long term follow-up study of 155 patients operated for ventral hernia with laparoscopic (LVHR) or open mesh repair (OVHR), including analyzing medical records, clinical investigation with patient-reported pain (VAS-scale), and MRI. MRI was performed in 124 patients: 114 patients (74%) after follow-up, and 10 patients referred for late complaints after ventral mesh repair. To verify the MRI-diagnosis of adhesions, laparoscopy was performed after MRI in a cohort of 20 patients. Results. MRI detected adhesions between bowel and abdominal wall/mesh in 60% of the patients and mesh shrinkage in 20-50%. Adhesions were demonstrated to all types of meshes after both LVHR and OVHR with a sensitivity of 70%, specificity of 75%, positive predictive value of 78%, and negative predictive value of 67%. Independent predictors for formation of adhesions were mesh area as determined by MRI and Charlson index. The presence of adhesions was not associated with more pain. Conclusion. MRI can detect adhesions between bowel and abdominal wall in a fair reliable way. Adhesions are formed both after open and laparoscopic hernia mesh repair and are not associated with chronic pain. PMID:26819601

  14. Pseudoelastic deformation during nanoscale adhesive contact formation.

    PubMed

    Mordehai, Dan; Rabkin, Eugen; Srolovitz, David J

    2011-08-26

    Molecular dynamics simulations are employed to demonstrate that adhesive contact formation through classical jump to contact is mediated by extensive dislocation activity in metallic nanoparticles. The dislocations generated during jump to contact are completely annihilated by the completion of the adhesive contact, leaving the nanoparticles dislocation-free. This rapid and efficient jump to contact process is pseudoelastic, rather than purely elastic or plastic. PMID:21929255

  15. Strategies to Minimize Adhesion Formation After Surgery

    PubMed Central

    Lazarou, George; Mondesir, Carlene; Wei, Kai; Khullar, Poonan; Ogden, Lorna

    2011-01-01

    Objectives: To compare the potential for postoperative laparoscopic adhesion formation utilizing either monopolar cautery or ultrasonic energy and to determine whether there is added benefit with the addition of a suspension of hyaluronate/carboxymethylcellulose in saline versus saline alone. Methods: Injuries were induced in rabbits by using monopolar cautery on 1 uterine horn and adjacent sidewall and ultrasonic energy on the opposite. Hyaluronate/ carboxymethylcellulose or saline was added to every other animal. Autopsies were performed after 3 weeks. Clinical and pathologic scoring of adhesions was performed by blinded investigators. Results: A very significant difference occurred in pathologic adhesion scores favoring the ultrasonic scalpel when the animals were treated with saline. However, a borderline significant difference was found in pathologic scores favoring the ultrasonic scalpel compared to the monopolar cautery. There was no significant difference in clinical adhesion scores between the 2 modalities. No significant difference in either score was found with the addition of hyaluronate/carboxymethylcellulose or saline with either instrument. Conclusion: No benefit was found for adhesion prevention with hyaluronate/carboxymethylcellulose. Although no reduction was achieved in clinical adhesions, the ultrasonic scalpel resulted in fewer histologic signs of tissue inflammation in the early postoperative period, suggesting that further clinical adhesions might develop over time with cautery. PMID:21985723

  16. Efficacy and safety of hyaluronate membrane in the rabbit cecum-abdominal wall adhesion model

    PubMed Central

    Kim, Jae Young; Cho, Wan Jin; Kim, Jun Ho; Lim, Sae Hwan; Kim, Hyun Jung; Lee, Young Woo

    2013-01-01

    Purpose Tissue adhesion is a well-known postsurgical phenomenon, causing pain, functional obstruction, and difficult reoperative surgery. To overcome these problems, various synthetic and natural polymer membranes have been developed as postoperative tissue adhesion barriers. However, limitation in their use has hindered its actual application. We prepared a hyaluronate membrane (HM) to evaluate its efficacy and safety as an adhesion barrier compared to a commercialized product (Interceed, Ethicon). Methods To evaluate the antiadhesion effect, a cecum-abdominal wall abrasion model was adopted in a rabbit. The denuded cecum was covered by Interceed or HM or neither and apposed to the abdominal wall (each, n = 10). Four weeks after surgery, the level of adhesion was graded. Acute and chronic toxicity of the three groups were also evaluated. Results Blood samples drawn to evaluate acute toxicity at postoperative day 3 and 7 showed no significant difference among the three groups. The grade and area of adhesion were significantly lower in the HM compared to those of the control and Interceed at four weeks after surgery. Histologic evaluations, which was carried out to estimate tissue reactions at the site of application, as well as to assess chronic toxicity for the major organs, were not significantly different in the three groups. Conclusion This study showed that the antiadhesion efficacy of HM was superior to commercialized antiadhesion membrane, Interceed. Low inflammatory response and nontoxicity were also demonstrated. From these results, we suggest that the HM is a good candidate as a tissue adhesion barrier. PMID:23908960

  17. A Novel Diagnostic Aid for Detection of Intra-Abdominal Adhesions to the Anterior Abdominal Wall Using Dynamic Magnetic Resonance Imaging

    PubMed Central

    Randall, David; Fenner, John; Gillott, Richard; ten Broek, Richard; Strik, Chema; Spencer, Paul; Bardhan, Karna Dev

    2016-01-01

    Introduction. Abdominal adhesions can cause serious morbidity and complicate subsequent operations. Their diagnosis is often one of exclusion due to a lack of a reliable, non-invasive diagnostic technique. Development and testing of a candidate technique are described below. Method. During respiration, smooth visceral sliding motion occurs between the abdominal contents and the walls of the abdominal cavity. We describe a technique involving image segmentation and registration to calculate shear as an analogue for visceral slide based on the tracking of structures throughout the respiratory cycle. The presence of an adhesion is attributed to a resistance to visceral slide resulting in a discernible reduction in shear. The abdominal movement due to respiration is captured in sagittal dynamic MR images. Results. Clinical images were selected for analysis, including a patient with a surgically confirmed adhesion. Discernible reduction in shear was observed at the location of the adhesion while a consistent, gradually changing shear was observed in the healthy volunteers. Conclusion. The technique and its validation show encouraging results for adhesion detection but a larger study is now required to confirm its potential. PMID:26880884

  18. Reduction of postsurgical adhesion formation with hydrogels synthesized by radiation

    NASA Astrophysics Data System (ADS)

    Nho, Young-Chang; Lee, Joon-Ho

    2005-07-01

    Biocompatible and biodegradable hydrogels based on carboxymethyl cellulose (CMC) and polyethyleneglycol (PEG) were prepared as physical barriers for preventing surgical adhesions. These interpolymeric hydrogels were synthesized by gamma irradiation crosslinking technique. A 1.5 cm × 1.5 cm of cecal serosa and an adjacent abdominal wall were abraded with bone burr until the serosal surface was disrupted and hemorrhagic but not perforated. The denuded cecum was covered with either CMC/PEG hydrogels or a solution from a CMC/PEG hydrogel. Control rat serosa was not covered. Two weeks later, the rats were sacrificed and the adhesion was scored on a 0-5 scale. Control rat showed a significantly higher incidence of adhesions than either the CMC/PEG hydrogels or a solution from the CMC/PEG hydrogel. In conclusion, these studies demonstrate that CMC/PEG hydrogels have a function of the prevention for an intra abdominal adhesion in a rat model.

  19. P-glycoprotein Mediates Postoperative Peritoneal Adhesion Formation by Enhancing Phosphorylation of the Chloride Channel-3

    PubMed Central

    Deng, Lulu; Li, Qin; Lin, Guixian; Huang, Dan; Zeng, Xuxin; Wang, Xinwei; Li, Ping; Jin, Xiaobao; Zhang, Haifeng; Li, Chunmei; Chen, Lixin; Wang, Liwei; Huang, Shulin; Shao, Hongwei; Xu, Bin; Mao, Jianwen

    2016-01-01

    P-glycoprotein (P-gp) is encoded by the multidrug resistance (MDR1) gene and is well studied as a multi-drug resistance transporter. Peritoneal adhesion formation following abdominal surgery remains an important clinical problem. Here, we found that P-gp was highly expressed in human adhesion fibroblasts and promoted peritoneal adhesion formation in a rodent model. Knockdown of P-gp expression by intraperitoneal injection of MDR1-targeted siRNA significantly reduced both the peritoneal adhesion development rate and adhesion grades. Additionally, we found that operative injury up-regulated P-gp expression in peritoneal fibroblasts through the TGF-β1/Smad signaling pathway and histone H3 acetylation. The overexpression of P-gp accelerated migration and proliferation of fibroblasts via volume-activated Cl- current and cell volume regulation by enhancing phosphorylation of the chloride channel-3. Therefore, P-gp plays a critical role in postoperative peritoneal adhesion formation and may be a valuable therapeutic target for preventing the formation of peritoneal adhesions. PMID:26877779

  20. Abdominal Adhesions

    MedlinePlus

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  1. Abdominal Adhesions

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  2. The Preventive Effect of Dexmedetomidine Against Postoperative Intra-abdominal Adhesions in Rats

    PubMed Central

    Kuru, Serdar; Bozkirli, Osman Bahadir; Barlas, Aziz Mutlu; Duymus, Mehmet Esat; Senes, Mehmet; Yumusak, Nihat; Yilmaz, Cevdet; Kismet, Kemal

    2015-01-01

    This study aimed to determine the possible preventive effects of dexmedetomidine on postoperative intra-abdominal adhesions. Dexmedetomidine is a highly selective and potent α2 adrenergic agonist with sedative, analgesic, anxiolytic, sympatholytic, hemodynamic, and diuretic properties. In recent years, investigations have shown that dexmedetomidine possesses secondary antioxidant and also anti-inflammatory effects. Thirty Wistar albino male rats were randomized and divided into 3 groups of 10 animals each: group 1, sham-operated; group 2, cecal abrasion + peritoneal dissection; group 3, cecal abrasion + peritoneal dissection followed by daily intravenous injection of 10 μg/kg dexmedetomidine for 10 days. The animals were killed on postoperative day 21. Blood and cecal samples were taken for biochemical and histopathologic evaluation. In this study, biochemical and pathologic parameters were significantly better in the cecal abrasion + peritoneal dissection + dexmedetomidine group when compared with the cecal abrasion + peritoneal dissection group. Tissue malondialdehyde, myeloperoxidase, total sulfhydryl, and catalase were found to be significantly different between the cecal abrasion/peritoneal dissection + dexmedetomidine and the cecal abrasion/peritoneal dissection groups. Plasma malondialdehyde and total sulfhydryl values were also statistically different between these groups (P < 0.05). Statistical analyses of mean pathologic scores showed that the histopathologic damage in the cecal abrasion/peritoneal dissection + dexmedetomidine group was significantly less than the damage in the control group (P < 0.05 for all pathologic parameters). The results of this study show that dexmedetomidine had a significant preventive effect on postoperative intra-abdominal adhesions. We concluded that these effects might be due to antioxidant and anti-inflammatory activities. PMID:25594644

  3. Impact of Intra-Abdominal Adhesion on Living Donor Right Hepatectomy.

    PubMed

    Kim, S H; Lee, S D; Kim, Y K; Park, S-J

    2016-06-01

    The impact of intra-abdominal adhesion (IAA) on living donor right hepatectomy (LDRH) remains to be clarified. The purpose of this study was to compare both the donor and recipient outcomes of right lobe living donor liver transplantation according to IAA detected intraoperatively. LDRH donors were identified through a prospectively maintained database at the authors' institution between March 2008 and February 2014. IAA was graded according to Beck et al (Dis Colon Rectum 2000; 43: 1749-1753). LDRH donors with IAA (group A) were matched 1:3 to those without IAA (group B) based on age, gender, and BMI. Perioperative data, complications by the Clavien classification, and the outcomes with at least 12 months follow-up were compared. Thirty-two (7.6%) of a total of 420 LDRH donors had IAA around the liver. Nineteen donors had previous abdominal surgery. LDRH was successfully completed under upper midline laparotomy in all donors. Compared with group B, group A had a longer operative time (270 vs. 172 min; p < 0.001), a higher wound complication rate (28.1% vs. 4.2%; p = 0.009), and a longer postoperative stay (10 vs. 7 days; p = 0.009). All donors recovered completely to their previous activities. The 1-year graft and recipient survivals of recipients were comparable between two groups. These findings support the feasibility and safety of LDRH in patients with IAA. PMID:26613370

  4. The comparison of the effects of ellagic acid and diclofenac sodium on intra-abdominal adhesion: an in vivo study in the rat model.

    PubMed

    Allahverdi, Tulay Diken; Allahverdi, Ertuğrul; Yayla, Sadık; Deprem, Turgay; Merhan, Oğuz; Vural, Sevil

    2014-01-01

    Peritoneal adhesions are seen frequently after abdominal surgery and can cause serious complications. We aimed to evaluate the effects of the oral use of diclofenac sodium and ellagic acid on formation of postoperative adhesions in rats Studies have shown that agents with anti-inflammatory properties and antioxidant substances can prevent adhesion by decreasing oxidative stress. We compared and evaluated the effects of ellagic acid that has strong antioxidant and anti-inflammatory properties and the nonsteroidal anti-inflammatory diclofenac sodium on peritoneal adhesion development in our experimental study. Laparotomy was performed with a midline incision under general anesthesia and an adhesion model was created on the antimesenteric side of the cecum in Groups I, II, and III. Group I received 85 mg/kg ellagic acid and Group II, 50 mg/kg diclofenac sodium through the nasogastric catheter while Group III received no medication. Only laparotomy was performed in Group IV. The rats were sacrificed at the end of the 14th day. Following macroscopic scoring, tissue samples were removed and subjected to biochemical and histopathologic evaluation. The degree of adhesion and the malondialdehyde level were decreased (P < 0.05), and glutathione level increased (P < 0.05) in Group I compared to Group II and Group III. The effects of ellagic acid on the prevention of peritoneal adhesion were found to be stronger than diclofenac sodium. This can be explained by the fact that ellagic acid is a strong antioxidant and decreases oxidative stress with anti-inflammatory and anti-angiogenic effects. PMID:25216418

  5. Comparison of Peritoneal Adhesion Formation in Bowel Retraction by Cotton Towels Versus the Silicone Lap Pak Device in a Rabbit Model

    PubMed Central

    Liu, Brian G.; Ruben, Dawn S.; Renz, Wolfgang; Santillan, Antonio; Kubisen, Steven J.; Harmon, John W.

    2011-01-01

    Objective: Manipulation of cotton operating room towels within the abdominal cavity in open abdominal surgery has been associated with the formation of peritoneal adhesions. In a rabbit model, the use of standard cotton operating room towels is compared to the Lap Pak, a silicone bowel-packing device, to determine the potential for reducing the risk of adhesions. Methods: Thirty rabbits were randomly assigned to 3 groups. The rabbits underwent a sham surgery with incision only (n = 10), placement of operating room towels (n = 10), or placement of a Lap Pak (n = 10). After 14 days, the rabbits were sacrificed and the peritoneal cavity explored for adhesions. The number, tenacity, ease of dissection, and density of adhesions were recorded, and the adhesions quantitatively graded using a Modified Hopkins Adhesion scoring system. Results: The operating room towel group had an average adhesion score of 2.5, and 8 (80%) rabbits developed adhesions. The sham group had an average adhesion score of 0.3 and one rabbit (10%) developed adhesions. The Lap Pak group had an average adhesion score of 0.2 and 1 rabbit (10%) developed adhesions. The frequency and severity of adhesions in the operating room towel group were significantly greater from that of the baseline sham group. There was no significant difference between the Lap Pak and sham groups. Conclusions: In this rabbit laparotomy model, the use of the Lap Pak to retract the bowels resulted in significantly fewer adhesions compared to cotton operating room towels. Lap Pak may be beneficial for bowel packing in general abdominal surgeries. PMID:22096614

  6. Formation of focal adhesion-stress fibre complexes coordinated by adhesive and non-adhesive surface domains.

    PubMed

    Zimerman, B; Arnold, M; Ulmer, J; Blümmel, J; Besser, A; Spatz, J P; Geiger, B

    2004-04-01

    Cell motility consists of repeating cycles of protrusion of a leading edge in the direction of migration, attachment of the advancing membrane to the matrix, and pulling of the trailing edge forward. In this dynamic process there is a major role for the cytoskeleton, which drives the protrusive events via polymerisation of actin in the lamellipodium, followed by actomyosin contractility. To study the transition of the actin cytoskeleton from a 'protrusive' to 'retractive' form, we have monitored the formation of focal adhesions and stress fibres during cell migration on a micro-patterned surface. This surface consisted of parallel arrays of 2 microm-wide, fibronectin-coated gold stripes, separated by non-adhesive (poly(ethylene glycol)-coated) glass areas with variable width, ranging from 4-12 microm. Monitoring the spreading of motile cells indicated that cell spreading was equally effective along and across the adhesive stripes, as long as the non-adhesive spaces between them did not exceed 6 microm. When the width of the PEG region was 8 microm or more, cells became highly polarised upon spreading, and failed to reach the neighboring adhesive stripes. It was also noted that as soon as the protruding lamella successfully crossed the PEG-coated area and reached an adhesive region, the organisation of actin in that area was transformed from a diffuse meshwork into a bundle, oriented perpendicularly to the stripes and anchored at its ends in focal adhesions. This transition depends on actomyosin-based contractility and is apparently triggered by the adhesion to the rigid fibronectin surface. PMID:16475844

  7. Phosphorylation of AKT and abdominal aortic aneurysm formation.

    PubMed

    Ghosh, Abhijit; Lu, Guanyi; Su, Gang; McEvoy, Brendan; Sadiq, Omar; DiMusto, Paul D; Laser, Adriana; Futchko, John S; Henke, Peter K; Eliason, Jonathan L; Upchurch, Gilbert R

    2014-01-01

    It is hypothesized that differential AKT phosphorylation between sexes is important in abdominal aortic aneurysm (AAA) formation. Male C57BL/6 mice undergoing elastase treatment showed a typical AAA phenotype (80% over baseline, P < 0.001) and significantly increased phosphorylated AKT-308 (p308) and total-AKT (T-AKT) at day 14 compared with female mice. Elastase-treated Raw cells produced increased p308 and significant amounts of matrix metalloproteinase 9 (MMP-9), and these effects were suppressed by LY294002 treatment, a known AKT inhibitor. Male and female rat aortic smooth muscle cells treated with elastase for 1, 6, or 24 hours demonstrated that the p308/T-AKT and AKT-Ser-473/T-AKT ratios peaked at 6 hours and were significantly higher in the elastase-treated cells compared with controls. Similarly, male cells had higher phosphorylated AKT/T-AKT levels than female cells. LY294002 also inhibited elastase-induced p308 formation more in female smooth muscle cells than in males, and the corresponding cell media had less pro-MMP-9. AKT siRNA significantly decreased secretion of pro-MMP-9, as well as pro-MMP-2 and active MMP-2 from elastase-treated male rat aortic smooth muscle cells. IHC of male mice AAA aortas showed increased p308, AKT-Ser-473, and T-AKT compared with female mice. Aortas from male AAA patients had a significantly higher p308/T-AKT ratio than female AAA tissues. These data suggest that AKT phosphorylation is important in the upstream regulation of MMP activity, and that differential phosphorylation may be important in sex differences in AAA. PMID:24332015

  8. CRITICAL ANALYSIS OF EXPERIMENTAL MODEL FOR STUDY OF ADHESIONS AFTER INCISIONAL HERNIAS INDUCED IN RATS’ AND REPAIR OF ABDOMINAL WALL WITH DIFFERENT BIOMATERIALS

    PubMed Central

    SERIGIOLLE, Leonardo Carvalho; BARBIERI, Renato Lamounier; GOMES, Helbert Minuncio Pereira; RODRIGUES, Daren Athiê Boy; STUDART, Sarah do Valle; LEME, Pedro Luiz Squilacci

    2015-01-01

    Background: Adhesions induced by biomaterials experimentally implanted in the abdominal cavity are basically studied by primary repair of different abdominal wall defects or by the correction of incisional hernias previously performed with no precise definition of the most appropriate model. Aim: To describe the adhesions which occur after the development of incisional hernias, before the prosthesis implantation, in an experimental model to study the changes induced by different meshes. Methods: Incisional hernias were performed in 10 rats with hernia orifices of standardized dimensions, obtained by the median incision of the abdominal wall and eversion of the defect edges. Ten days after the procedure adhesions of abdominal structures were found when hernias were repaired with different meshes. Results: The results showed hernia sac well defined in all rats ten days after the initial procedure. Adhesions of the greater omentum occurred in five animals of which two also showed adhesions of small bowel loops besides the omentum, and another two showed liver adhesions as well as the greater omentum, numbers with statistical significance by Student's t test (p<0.05). Conclusion: Although it reproduces the real clinical situation, the choice of experimental model of incisional hernia repair previously induced implies important adhesions, with possible repercussions in the evaluation of the second operation, when different implants of synthetic materials are used. PMID:26537141

  9. 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. PMID:26001706

  10. In situ cross-linkable hyaluronic acid hydrogels prevent post-operative abdominal adhesions in a rabbit model.

    PubMed

    Yeo, Yoon; Highley, Christopher B; Bellas, Evangelia; Ito, Taichi; Marini, Robert; Langer, Robert; Kohane, Daniel S

    2006-09-01

    We studied the efficacy of an in situ cross-linked hyaluronic acid hydrogel (HAX) in preventing post-surgical peritoneal adhesions, using a rabbit sidewall defect-cecum abrasion model. Two cross-linkable precursors were prepared by modifying hyaluronic acid with adipic dihydrazide and aldehyde, respectively. The hydrogel precursors cross-linked to form a flexible hydrogel upon mixing. The hydrogel was biodegradable and provided a durable physical barrier, which was highly effective in reducing the formation of post-operative adhesions. Ten out of 12 animals in the untreated control group developed fibrous adhesions requiring sharp dissection, while only 2 out of 8 animals treated with HAX gels showed such adhesions, and those occurred in locations that were not covered by the hydrogel. We also studied means by which gel degradation time can be modulated by varying the precursor concentration and molecular weight. PMID:16750564

  11. Platelet adhesion signalling and the regulation of thrombus formation.

    PubMed

    Gibbins, Jonathan M

    2004-07-15

    Platelets perform a central role in haemostasis and thrombosis. They adhere to subendothelial collagens exposed at sites of blood vessel injury via the glycoprotein (GP) Ib-V-IX receptor complex, GPVI and integrin alpha(2)beta(1). These receptors perform distinct functions in the regulation of cell signalling involving non-receptor tyrosine kinases (e.g. Src, Fyn, Lyn, Syk and Btk), adaptor proteins, phospholipase C and lipid kinases such as phosphoinositide 3-kinase. They are also coupled to an increase in cytosolic calcium levels and protein kinase C activation, leading to the secretion of paracrine/autocrine platelet factors and an increase in integrin receptor affinities. Through the binding of plasma fibrinogen and von Willebrand Factor to integrin alpha(IIb)beta(3), a platelet thrombus is formed. Although increasing evidence indicates that each of the adhesion receptors GPIb-V-IX and GPVI and integrins alpha(2)beta(1) and alpha(IIb)beta(3) contribute to the signalling that regulates this process, the individual roles of each are only beginning to be dissected. By contrast, adhesion receptor signalling through platelet endothelial cell adhesion molecule 1 (PECAM-1) is implicated in the inhibition of platelet function and thrombus formation in the healthy circulation. Recent studies indicate that understanding of platelet adhesion signalling mechanisms might enable the development of new strategies to treat and prevent thrombosis. PMID:15252124

  12. Preoperative Association of Abdominal Striae Gravidarum with Intraabdominal Adhesions in Pregnant Women with a History of Previous Cesarean Section: a Cross-sectional Study

    PubMed Central

    Dogan, A.; Ertas, I. E.; Uyar, I.; Karaca, I.; Bozgeyik, B.; Töz, E.; Ozeren, M.

    2016-01-01

    Introduction: Intraabdominal adhesions that develop because of prior abdominal or pelvic surgery may cause problems during surgery. Complications can include difficult intraabdominal entry; injury to the urinary bladder, uterus or small intestine; longer operation times, and increased blood loss. The goal of the present study was to evaluate the association between abdominal striae gravidarum and intraabdominal adhesions in the preoperative period in pregnant women with a history of cesarean section. Materials and Methods: The study included 247 pregnant women at ≥ 37 weeks of gestation admitted to the labor unit for delivery; all had undergone at least one previous cesarean section. Abdominal striae were assessed preoperatively using the Davey scoring system; the severity and intensity of adhesions were subsequently evaluated intraoperatively according to the modified Nair scoring system. Results: No striae were seen in 104 pregnant women; 41 had mild striae and 102 had severe striae. Overall, 113 cases had no adhesions (grade 0), 106 had grade 1–2 adhesions, and 28 had grade 3–4 adhesions. Among patients with grade 0 adhesions, 34 (13.7 %) had no striae, while 79 (31.9 %) had mild-to-severe striae (p < 0.001; sensitivity 55 %; specificity 67 %; positive predictive value 69 %; negative predictive value 52 %). Among women with grade 1–2 adhesions, 48 (19.4 %) had no striae, while 58 (23.4 %) had mild-to-severe striae. Finally, among women with grade 3–4 adhesions, 22 (8.9 %) had no striae, while 6 (2.4 %) had mild-to-severe striae (p < 0.001). A p-value < 0.05 was taken to indicate statistical significance. Conclusions: The abdominal adhesion score dropped as the abdominal striae gravidarum score rose during the preoperative period. Addition of this useful, easy-to-apply, inexpensive, adjunctive, observational, abdominal scoring method to the obstetrical work-up can provide important clues about the intraabdominal adhesion

  13. The Effect of Antivascular Endothelial Growth Factor on the Development of Adhesion Formation in Laparotomized Rats: Experimental Study

    PubMed Central

    Basbug, Murat; Bulbuller, Nurullah; Camci, Cemalettin; Ayten, Refik; Aygen, Erhan; Ozercan, Ibrahim Hanifi; Arikanoglu, Zulfu; Akbulut, Sami

    2011-01-01

    Aims. This study determined the effects of a single dose of bevacizumab, an antiangiogenic recombinant monoclonal antibody that specifically targets vascular endothelial growth factor (VEGF), on adhesion formation in the rat cecal abrasion model. Methodology. Thirty female Wistar albino rats (200–224 g) were divided into three groups. All rats underwent laparotomy at which time cecal wall abrasion and abdominal wall injuries were induced. Group I (control) underwent only the abrasion procedure; Groups II and III received saline or bevacizumab intraperitoneally, respectively, following the abrasion. The rats were killed on postoperative day 7, and the severity of adhesions was evaluated, together with histopathological fibrosis parameters and immunohistochemical staining to identify the VEGF receptor. Results. The mean adhesion severity score in Groups I–III was 2.5 ± 0.52, 2.4 ± 0.69, and 0.7 ± 0.82, respectively; the score in Group III was significantly lower than that in Groups I (P < 0.001) and II (P < 0.001). In the histopathological evaluation, the mean fibrosis score in Group III was significantly lower that the scores in Groups I (P < 0.001) and II (P < 0.001). VEGF staining of the adhesion areas in Group III was significantly lower than that in Groups I (P < 0.001) and II (P < 0.001). Conclusion. Bevacizumab decreases adhesion formation following laparotomy in rats by blocking VEGF receptor occupancy. PMID:21760775

  14. Deacetylation of Fungal Exopolysaccharide Mediates Adhesion and Biofilm Formation

    PubMed Central

    Lee, Mark J.; Geller, Alexander M.; Bamford, Natalie C.; Liu, Hong; Gravelat, Fabrice N.; Snarr, Brendan D.; Le Mauff, François; Chabot, Joseé; Ralph, Benjamin; Ostapska, Hanna; Lehoux, Mélanie; Cerone, Robert P.; Baptista, Stephanie D.; Vinogradov, Evgeny; Filler, Scott G.; Howell, P. Lynne

    2016-01-01

    ABSTRACT The mold Aspergillus fumigatus causes invasive infection in immunocompromised patients. Recently, galactosaminogalactan (GAG), an exopolysaccharide composed of galactose and N-acetylgalactosamine (GalNAc), was identified as a virulence factor required for biofilm formation. The molecular mechanisms underlying GAG biosynthesis and GAG-mediated biofilm formation were unknown. We identified a cluster of five coregulated genes that were dysregulated in GAG-deficient mutants and whose gene products share functional similarity with proteins that mediate the synthesis of the bacterial biofilm exopolysaccharide poly-(β1-6)-N-acetyl-d-glucosamine (PNAG). Bioinformatic analyses suggested that the GAG cluster gene agd3 encodes a protein containing a deacetylase domain. Because deacetylation of N-acetylglucosamine residues is critical for the function of PNAG, we investigated the role of GAG deacetylation in fungal biofilm formation. Agd3 was found to mediate deacetylation of GalNAc residues within GAG and render the polysaccharide polycationic. As with PNAG, deacetylation is required for the adherence of GAG to hyphae and for biofilm formation. Growth of the Δagd3 mutant in the presence of culture supernatants of the GAG-deficient Δuge3 mutant rescued the biofilm defect of the Δagd3 mutant and restored the adhesive properties of GAG, suggesting that deacetylation is an extracellular process. The GAG biosynthetic gene cluster is present in the genomes of members of the Pezizomycotina subphylum of the Ascomycota including a number of plant-pathogenic fungi and a single basidiomycete species, Trichosporon asahii, likely a result of recent horizontal gene transfer. The current study demonstrates that the production of cationic, deacetylated exopolysaccharides is a strategy used by both fungi and bacteria for biofilm formation. PMID:27048799

  15. Cytotoxicity of Cyanoacrylate-Based Tissue Adhesives and Short-Term Preclinical In Vivo Biocompatibility in Abdominal Hernia Repair

    PubMed Central

    Rodríguez, Marta; Pérez-Köhler, Bárbara; Kühnhardt, Andreé; Fernández-Gutiérrez, Mar; San Román, Julio; Bellón, Juan Manuel

    2016-01-01

    Background Cyanoacrylate(CA)-based tissue adhesives, although not widely used, are a feasible option to fix a mesh during abdominal hernia repair, due to its fast action and great bond strength. Their main disadvantage, toxicity, can be mitigated by increasing the length of their alkyl chain. The objective was to assess the in vitro cytotoxicity and in vivo biocompatibility in hernia repair of CAs currently used in clinical practice (Glubran(n-butyl) and Ifabond(n-hexyl)) and a longer-chain CA (OCA(n-octyl)), that has never been used in the medical field. Methods Formaldehyde release and cytotoxicity of unpolymerized(UCAs) and polymerized CAs(PCAs) were evaluated by macroscopic visual assessment, flow cytometry and Alamar Blue assays. In the preclinical evaluation, partial defects were created in the rabbit abdominal wall and repaired by fixing polypropylene prostheses using the CAs. At 14 days post-surgery, animals were euthanized for morphology, macrophage response and cell damage analyses. Results Formaldehyde release was lower as the molecular weight of the monomer increased. The longest side-chain CA(OCA) showed the highest cytotoxicity in the UCA condition. However, after polymerization, was the one that showed better behavior on most occasions. In vivo, all CAs promoted optimal mesh fixation without displacements or detachments. Seroma was evident with the use of Glubran, (four of six animals: 4/6) and Ifabond (2/6), but it was reduced with the use of OCA (1/6). Significantly greater macrophage responses were observed in groups where Glubran and Ifabond were used vs. sutures and OCA. TUNEL-positive cells were significantly higher in the Glubran and OCA groups vs. the suture group. Conclusions Although mild formaldehyde release occurred, OCA was the most cytotoxic during polymerization but the least once cured. The CAs promoted proper mesh fixation and have potential to replace traditional suturing techniques in hernia repair; the CAs exhibited good tissue

  16. Adhesion and formation of microbial biofilms in complex microfluidic devices

    SciTech Connect

    Kumar, Aloke; Karig, David K; Neethirajan, Suresh; Suresh, Anil K; Srijanto, Bernadeta R; Mukherjee, Partha P; Retterer, Scott T; Doktycz, Mitchel John

    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 in 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.

  17. Hydrogel Adhesion with Wrinkle Formation by Spatial Control of Polymer Networks.

    PubMed

    Kato, Masatoshi; Tsuboi, Yasuyuki; Kikuchi, Akihiko; Asoh, Taka-Aki

    2016-06-01

    We prepared a novel wrinkled adhesive interface of hydrogels for strong adhesion via spatial control of polymer networks, including the density, distribution, and mobility of interactive units. A wrinkle structure was formed by the elasticity mismatch of hydrogels and adhesive polyion complex layers when electrophoresis was carried out between cationic and anionic semi-IPNs. The wrinkling wavelength of interfaces was controlled by Young's modulus of hydrogels. The role of wrinkle structure in adhesion was investigated by the measurement of the adhesive strength of hydrogels which were adhered under the compression, resulting in the disappearance of the wrinkle structure by compression that induced a decrease in adhesive strength. These results indicate that strong hydrogel adhesion was achieved by both the spatial design of interactive units and wrinkle formation. PMID:27187544

  18. Proneural and Abdominal Hox Inputs Synergize to Promote Sensory Organ Formation in the Drosophila Abdomen

    PubMed Central

    Gutzwiller, Lisa M.; Witt, Lorraine M.; Gresser, Amy L.; Burns, Kevin A.; Cook, Tiffany A.; Gebelein, Brian

    2010-01-01

    The atonal (ato) proneural gene specifies a stereotypic number of sensory organ precursors (SOP) within each body segment of the Drosophila ectoderm. Surprisingly, the broad expression of Ato within the ectoderm results in only a modest increase in SOP formation, suggesting many cells are incompetent to become SOPs. Here, we show that the SOP promoting activity of Ato can be greatly enhanced by three factors: the Senseless (Sens) zinc finger protein, the Abdominal-A (Abd-A) Hox factor, and the epidermal growth factor (EGF) pathway. First, we show that expression of either Ato alone or with Sens induces twice as many SOPs in the abdomen as in the thorax, and do so at the expense of an abdomen-specific cell fate: the larval oenocytes. Second, we demonstrate that Ato stimulates abdominal SOP formation by synergizing with Abd-A to promote EGF ligand (Spitz) secretion and secondary SOP recruitment. However, we also found that Ato and Sens selectively enhance abdominal SOP development in a Spitz-independent manner, suggesting additional genetic interactions between this proneural pathway and Abd-A. Altogether, these experiments reveal that genetic interactions between EGF-signaling, Abd-A, and Sens enhance the SOP-promoting activity of Ato to stimulate region-specific neurogenesis in the Drosophila abdomen. PMID:20875816

  19. Formation of tunable graphene oxide coating with high adhesion.

    PubMed

    Lin, Liangxu; Wu, Huaping; Green, Stephen J; Crompton, Joanna; Zhang, Shaowei; Horsell, David W

    2016-02-10

    Graphene oxide (GO) can be applied as a coating on metals, but few of these coatings have an adhesion suitable for practical applications. We demonstrate here how to form a GO coating on metals with a high adhesion (∼10.6 MPa) and tuneable surface, which can be further applied using similar/modified techniques for special applications (e.g. anti-corrosion and anti-biofouling). PMID:26814138

  20. An Integrated Fluid-Chemical Model Toward Modeling the Formation of Intra-Luminal Thrombus in Abdominal Aortic Aneurysms

    PubMed Central

    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. PMID:22934022

  1. Septic pleuritis and abdominal abscess formation caused by Rhodococcus equi in a foal.

    PubMed

    Valdes, Alejandro; Johnson, Jill R

    2005-09-15

    A 3-month-old female Arabian horse was evaluated because of fever, respiratory distress, lethargy, and decreased appetite of 5 days' duration. Pleural effusion was diagnosed on the basis of ultrasonographic and radiographic examinations. Cytologic examination of pleural fluid collected via thoracocentesis revealed septic inflammation; bacteriologic culture of a sample of that fluid yielded Rhodococcus equi. A large intra-abdominal mass adjacent to the body wall was identified ultrasonographically. A specimen of the mass was collected via aspiration; the specimen was identified cytologically as purulent exudate that contained large numbers of rod-shaped bacteria, which confirmed abdominal abscess formation. Bacteriologic culture of a sample of the exudate also yielded R. equi. The foal was treated with azithromycin (10 mg/kg [4.5 mg/lb], PO, q 24 h for 5 days then q 48 h) and rifampin (5 mg/kg [2.3 mg/lb], PO, q 12 h) for 8 weeks and metronidazole (15 mg/kg [6.8 mg/lb], PO, q 8 h) for 3 weeks. Clinically, the foal responded to antimicrobial treatment within 2 weeks. At 8 weeks after the initial evaluation, ultrasonographic examination of the foal revealed resolution of the pleural effusion and abdominal abscess. In foals, R. equi infection typically results in pyogranulomatous pneumonia, and pleural effusion is an uncommon clinical sign. The combination of azithromycin and rifampin appears to be an effective treatment for R. equi infection in foals. PMID:16190597

  2. Effect of the Mode of Application of Cryopreserved Human Amniotic Membrane on Adhesion Formation after Abdomino-Pelvic Surgery in a Mouse Model

    PubMed Central

    Nassif, Joseph; Abbasi, Sehrish A.; Kechli, Mohamad Karim; Boutary, Suzan S.; Ghulmiyyah, Labib; Khalifeh, Ibrahim; Abou Ghaddara, Hussein; Nassar, Anwar H.

    2016-01-01

    Adhesions after abdomino-pelvic surgery are a cause of morbidity and reoperations. The use of human amniotic membrane (HAM) for adhesion prevention has given controversial results. The mode of administration of the amniotic membrane has not been well studied. This study assessed the efficacy of two modes of application of cryopreserved HAM, patch or fragmented in Lactated Ringer (LR) solution, for the prevention of pelvic adhesion formation postabdomino-pelvic surgery in a mice model. After a midline laparotomy incision, a small cautery lesion was done on each side of the abdominal wall peritoneum in mice. In Group A (control; n = 42), the abdomen was closed directly, Group B (n = 42) received 2.5 ml of LR prior to closure. In Groups C (n = 42) and D (n = 42), a 2 cm × 2 cm patch of HAM and another one fragmented and dispersed in 2.5 ml of LR were applied prior to closure, respectively. Two weeks later, a laparotomy was performed, and gross and pathological evaluation of adhesions, fibrosis, angiogenesis, and inflammation were conducted. Group D exhibited a significantly lower rate of gross adhesion formation. Fibrosis was significantly lowest in Group C as compared to the control. Group B had the lowest vascular formation in the adhesions. The use of HAM fragmented in LR solution is associated with a significantly lower incidence of postoperative adhesions in mice when compared to LR alone, HAM patch, or control. The mechanism of action of this reduction needs to be elucidated by future studies. PMID:27066485

  3. 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

  4. Effect of Antibacterial Dental Adhesive on Multispecies Biofilms Formation

    PubMed Central

    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.

    2015-01-01

    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

  5. 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

  6. Effect of intraperitoneal cetuximab administration on colonic anastomosis and early postoperative adhesion formation in a rat model

    PubMed Central

    Kurt, Atilla; Karanlık, Hasan; Soylu, Sinan; Özgür, İlker; Soydinç, Hilal Oğuz; Duranyıldız, Derya; Olgaç, Vakur; Şen, Fatma; Asoğlu, Oktar

    2016-01-01

    Objective We aimed to evaluate the effect of intraperitoneal cetuximab administration on the healing of anastomosis and development of early adhesion formation in a rat model. Materials and Methods Twenty-four female rats were used. A colon segment was resected and end-to-end anastomosis was performed. The rats were randomized into three groups after the performance of colonic anastomosis and received 10 mL of intraperitoneal solution including study drugs after closure of abdominal cavity: normal saline was administered to the normal saline group (n=8), cetuximab (400 mg/m2) was administered to the postoperative 1 group (n=8) 1 day after surgery, and cetuximab (400 mg/m2) was administered to the peroperative group (n=8) during surgery. Results The mean adhesion grade was 2.63±0.92, and 0.50±0.76 and 0.63±0.74 for control and test groups, respectively. Cetuximab reduced adhesion formation in test groups (p<0.05). When all groups were compared, it was found that vascular endothelial growth factor levels decreased significantly only in the abdomen (p<0.05). Hydroxyproline levels and anastomosis bursting pressure were examined, and a statistical difference was found between groups (hydroxyproline p<0.05, bursting pressure p<0.05). However, when postoperative 1 day group was compared with the control group, it was found that there was no difference between groups according to these parameters (p>0.05), but when peroperative group was compared with the control group a significant decrease was observed in both parameters. Histopathological healing score was also evaluated. No statistical difference between groups was found. Conclusion Twenty-four hours later from the operation, intraperitoneal cetuximab therapy may be a safe and feasible treatment for metastatic colorectal patients. PMID:27528807

  7. Interfacial pH during mussel adhesive plaque formation.

    PubMed

    Martinez Rodriguez, Nadine R; Das, Saurabh; Kaufman, Yair; Israelachvili, Jacob N; Waite, J Herbert

    2015-01-01

    Mussel (Mytilus californianus) adhesion to marine surfaces involves an intricate and adaptive synergy of molecules and spatio-temporal processes. Although the molecules, such as mussel foot proteins (mfps), are well characterized, deposition details remain vague and speculative. Developing methods for the precise surveillance of conditions that apply during mfp deposition would aid both in understanding mussel adhesion and translating this adhesion into useful technologies. To probe the interfacial pH at which mussels buffer the local environment during mfp deposition, a lipid bilayer with tethered pH-sensitive fluorochromes was assembled on mica. The interfacial pH during foot contact with modified mica ranged from 2.2 to 3.3, which is well below the seawater pH of ~ 8. The acidic pH serves multiple functions: it limits mfp-Dopa oxidation, thereby enabling the catecholic functionalities to adsorb to surface oxides by H-bonding and metal ion coordination, and provides a solubility switch for mfps, most of which aggregate at pH ≥ 7-8. PMID:25875963

  8. Interfacial pH during mussel adhesive plaque formation

    PubMed Central

    Rodriguez, Nadine R. Martinez; Das, Saurabh; Kaufman, Yair; Israelachvili, Jacob N.; Waite, J. Herbert

    2015-01-01

    Mussel (Mytilus californianus) adhesion to marine surfaces involves an intricate and adaptive synergy of molecules and spatio-temporal processes. Although the molecules, such as mussel foot proteins (mfps), are well characterized, deposition details remain vague and speculative. Developing methods for the precise surveillance of conditions that apply during mfp deposition would aid both in understanding mussel adhesion and translating this adhesion into useful technologies. To probe the interfacial pH at which mussels buffer the local environment during mfp deposition, a lipid bilayer with tethered pH-sensitive fluorochromes was assembled on mica. The interfacial pH during foot contact with modified mica ranged from 2.2−3.3, which is well below the seawater pH of ~8. The acidic pH serves multiple functions: it limits mfp-Dopa oxidation, thereby enabling the catecholic functionalities to adsorb to surface oxides by H-bonding and metal ion coordination, and provides a solubility switch for mfps, most of which aggregate at pH ≥ 7-8. PMID:25875963

  9. 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. PMID:26456320

  10. 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

  11. Comparative dynamics of retrograde actin flow and focal adhesions: formation of nascent adhesions triggers transition from fast to slow flow.

    PubMed

    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

  12. Efficiency of heating methods for polymer fibers with formation of adhesion compounds

    SciTech Connect

    Markova, L.V.; Markov, E.M.; Pinchuk, I.S.

    1995-12-01

    Efficiency of contact and contactless methods of heating of a fiber polymer material upon formation of adhesion compounds between its layers is analyzed. The advisability of contact heating in the preliminary stage and contactless heating in the final stage of formation of compounds is shown.

  13. Formation of an artificial blood vessel: adhesion force measurements with optical tweezers

    NASA Astrophysics Data System (ADS)

    Knoener, Gregor; Campbell, Julie H.; Heckenberg, Norman R.; Rubinsztein-Dunlop, Halina

    2004-10-01

    We are investigating the formation of a tissue capsule around a foreign body. This tissue capsule can be used as an autologous graft for the replacement of diseased blood vessels or for bypass surgery. The graft is grown in the peritoneal cavity of the recipient and the formation starts with the adhesion of cells to the foreign body. We identify the cell type and measure the adhesion of these cells to foreign materials using optical tweezers. Cell adhesion to macroscopic samples and microspheres is investigated. No difference in the adhesion force was measurable for polyethylene, silicon and Tygon on a scale accessible to optical tweezers. The density of adherent cells was found to vary strongly, being highest on polyethylene. The mean rupture forces for cell-microsphere adhesion ranged from 24 to 39 pN and changed upon preadsorption of bovine serum albumin. For plain microspheres, the highest mean rupture force was found for PMMA, which also showed the highest adhesion probability for the cell-microsphere interaction.

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

    PubMed Central

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

    2015-01-01

    Objectives: To investigate the effects of intravenous infliximab in preventing the formation of peritoneal adhesions in an animal model of rat. Methods: 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. Results: 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). Conclusion: Administration of intravenous infliximab after intraabdominal surgicalprocedures would not prevent the formation of peritoneal adhesions in animal model of albino rat. PMID:27162911

  15. Effect of hyaluronic acid on postoperative intraperitoneal adhesion formation in the rat model

    SciTech Connect

    Urman, B.; Gomel, V.; Jetha, N. )

    1991-09-01

    The aim of this study was to determine the effectiveness of hyaluronic acid solution in preventing intraperitoneal (IP) adhesions. The study design was prospective, randomized and blinded and involved 83 rats. Measured serosal injury was inflicted using a CO2 laser on the right uterine horn of the rat. Animals randomized to groups 1 and 2 received either 0.4% hyaluronic acid or its diluent phosphate-buffered saline (PBS) intraperitoneally before and after the injury. In groups 3 and 4, the same solutions were used only after the injury. Postoperative adhesions were assessed at second-look laparotomy. Histologic assessment of the fresh laser injury was carried out on uteri pretreated with hyaluronic acid, PBS, or nothing. Pretreatment with hyaluronic acid was associated with a significant reduction in postoperative adhesions and a significantly decreased crater depth. Hyaluronic acid appears to reduce postoperative IP adhesion formation by coating the serosal surfaces and decreasing the extent of initial tissue injury.

  16. Lamellipodial actin mechanically links myosin activity with adhesion-site formation.

    PubMed

    Giannone, Grégory; Dubin-Thaler, Benjamin J; Rossier, Olivier; Cai, Yunfei; Chaga, Oleg; Jiang, Guoying; Beaver, William; Döbereiner, Hans-Günther; Freund, Yoav; Borisy, Gary; Sheetz, Michael P

    2007-02-01

    Cell motility proceeds by cycles of edge protrusion, adhesion, and retraction. Whether these functions are coordinated by biochemical or biomechanical processes is unknown. We find that myosin II pulls the rear of the lamellipodial actin network, causing upward bending, edge retraction, and initiation of new adhesion sites. The network then separates from the edge and condenses over the myosin. Protrusion resumes as lamellipodial actin regenerates from the front and extends rearward until it reaches newly assembled myosin, initiating the next cycle. Upward bending, observed by evanescence and electron microscopy, results in ruffle formation when adhesion strength is low. Correlative fluorescence and electron microscopy shows that the regenerating lamellipodium forms a cohesive, separable layer of actin above the lamellum. Thus, actin polymerization periodically builds a mechanical link, the lamellipodium, connecting myosin motors with the initiation of adhesion sites, suggesting that the major functions driving motility are coordinated by a biomechanical process. PMID:17289574

  17. Systemic EP4 Inhibition Increases Adhesion Formation in a Murine Model of Flexor Tendon Repair

    PubMed Central

    Geary, Michael B.; Orner, Caitlin A.; Bawany, Fatima; Awad, Hani A.; Hammert, Warren C.; O’Keefe, Regis J.; Loiselle, Alayna E.

    2015-01-01

    Flexor tendon injuries are a common clinical problem, and repairs are frequently complicated by post-operative adhesions forming between the tendon and surrounding soft tissue. Prostaglandin E2 and the EP4 receptor have been implicated in this process following tendon injury; thus, we hypothesized that inhibiting EP4 after tendon injury would attenuate adhesion formation. A model of flexor tendon laceration and repair was utilized in C57BL/6J female mice to evaluate the effects of EP4 inhibition on adhesion formation and matrix deposition during flexor tendon repair. Systemic EP4 antagonist or vehicle control was given by intraperitoneal injection during the late proliferative phase of healing, and outcomes were analyzed for range of motion, biomechanics, histology, and genetic changes. Repairs treated with an EP4 antagonist demonstrated significant decreases in range of motion with increased resistance to gliding within the first three weeks after injury, suggesting greater adhesion formation. Histologic analysis of the repair site revealed a more robust granulation zone in the EP4 antagonist treated repairs, with early polarization for type III collagen by picrosirius red staining, findings consistent with functional outcomes. RT-PCR analysis demonstrated accelerated peaks in F4/80 and type III collagen (Col3a1) expression in the antagonist group, along with decreases in type I collagen (Col1a1). Mmp9 expression was significantly increased after discontinuing the antagonist, consistent with its role in mediating adhesion formation. Mmp2, which contributes to repair site remodeling, increases steadily between 10 and 28 days post-repair in the EP4 antagonist group, consistent with the increased matrix and granulation zones requiring remodeling in these repairs. These findings suggest that systemic EP4 antagonism leads to increased adhesion formation and matrix deposition during flexor tendon healing. Counter to our hypothesis that EP4 antagonism would improve the

  18. Systemic EP4 Inhibition Increases Adhesion Formation in a Murine Model of Flexor Tendon Repair.

    PubMed

    Geary, Michael B; Orner, Caitlin A; Bawany, Fatima; Awad, Hani A; Hammert, Warren C; O'Keefe, Regis J; Loiselle, Alayna E

    2015-01-01

    Flexor tendon injuries are a common clinical problem, and repairs are frequently complicated by post-operative adhesions forming between the tendon and surrounding soft tissue. Prostaglandin E2 and the EP4 receptor have been implicated in this process following tendon injury; thus, we hypothesized that inhibiting EP4 after tendon injury would attenuate adhesion formation. A model of flexor tendon laceration and repair was utilized in C57BL/6J female mice to evaluate the effects of EP4 inhibition on adhesion formation and matrix deposition during flexor tendon repair. Systemic EP4 antagonist or vehicle control was given by intraperitoneal injection during the late proliferative phase of healing, and outcomes were analyzed for range of motion, biomechanics, histology, and genetic changes. Repairs treated with an EP4 antagonist demonstrated significant decreases in range of motion with increased resistance to gliding within the first three weeks after injury, suggesting greater adhesion formation. Histologic analysis of the repair site revealed a more robust granulation zone in the EP4 antagonist treated repairs, with early polarization for type III collagen by picrosirius red staining, findings consistent with functional outcomes. RT-PCR analysis demonstrated accelerated peaks in F4/80 and type III collagen (Col3a1) expression in the antagonist group, along with decreases in type I collagen (Col1a1). Mmp9 expression was significantly increased after discontinuing the antagonist, consistent with its role in mediating adhesion formation. Mmp2, which contributes to repair site remodeling, increases steadily between 10 and 28 days post-repair in the EP4 antagonist group, consistent with the increased matrix and granulation zones requiring remodeling in these repairs. These findings suggest that systemic EP4 antagonism leads to increased adhesion formation and matrix deposition during flexor tendon healing. Counter to our hypothesis that EP4 antagonism would improve the

  19. Focal Adhesion Kinase regulates cell-cell contact formation in epithelial cells via modulation of Rho

    SciTech Connect

    Playford, Martin P.; Vadali, Kavita; Cai Xinming; Burridge, Keith; Schaller, Michael D.

    2008-10-15

    Focal Adhesion Kinase (FAK) is a non-receptor tyrosine kinase that plays a key role in cellular processes such as cell adhesion, migration, proliferation and survival. Recent studies have also implicated FAK in the regulation of cell-cell adhesion. Here, evidence is presented showing that siRNA-mediated suppression of FAK levels in NBT-II cells and expression of dominant negative mutants of FAK caused loss of epithelial cell morphology and inhibited the formation of cell-cell adhesions. Rac and Rho have been implicated in the regulation of cell-cell adhesions and can be regulated by FAK signaling. Expression of active Rac or Rho in NBT-II cells disrupted formation of cell-cell contacts, thus promoting a phenotype similar to FAK-depleted cells. The loss of intercellular contacts in FAK-depleted cells is prevented upon expression of a dominant negative Rho mutant, but not a dominant negative Rac mutant. Inhibition of FAK decreased tyrosine phosphorylation of p190RhoGAP and elevated the level of GTP-bound Rho. This suggests that FAK regulates cell-cell contact formation by regulation of Rho.

  20. Efficient inhibition of the formation of joint adhesions by ERK2 small interfering RNAs

    SciTech Connect

    Li, Fengfeng; Ruan, Hongjiang; Fan, Cunyi; Zeng, Bingfang; Wang, Chunyang; Wang, Xiang

    2010-01-01

    Transforming growth factor-{beta}1 and fibroblast growth factor-2 play very important roles in fibroblast proliferation and collagen expression. These processes lead to the formation of joint adhesions through the SMAD and MAPK pathways, in which extracellular signal-regulated kinase (ERK)2 is considered to be crucial. Based on these theories, we examined the effects of a lentivirus-mediated small interfering RNA (siRNA) targeting ERK2 on the suppression of joint adhesion formation in vivo. The effects were assessed in vivo from different aspects including the adhesion score, histology and joint contracture angle. We found that the adhesions in the ERK2 siRNA group became soft and weak, and were easily stretched. Accordingly, the flexion contracture angles in the ERK2 siRNA group were also reduced (P < 0.05 compared with the control group). The animals appeared healthy, with no signs of impaired wound healing. In conclusion, local delivery of a lentivirus-mediated siRNA targeting ERK2 can ameliorate joint adhesion formation effectively and safely.

  1. Effect of viscous macromolecules on peritoneal plasminogen activator activity: a potential mechanism for their ability to reduce postoperative adhesion formation.

    PubMed

    Mayer, M; Yedgar, S; Hurwitz, A; Palti, Z; Finzi, Z; Milwidsky, A

    1988-10-01

    Activity of peritoneal plasminogen activator and its regulation by dextran and other macromolecules that clinically suppress postoperative adhesions was studied. Plasminogen activator activity was assayed by a two-stage globinolytic assay that monitors formation of plasmin, as well as by cleavage of a chromogenic peptide substrate (S-2444) in the presence of aprotinin (Trasylol). Plasminogen activator activity was located on the outer surface of human peritoneum. Incubation of peritoneal tissue with buffer in vitro (conditioning) prompted release of plasminogen activator into the conditioning medium. The released plasminogen activator formed a single band on sodium dodecyl sulfate-gel electrophoresis at an apparent molecular weight of 174,000 and was markedly suppressed by antiserum raised against human melanoma tissue-type plasminogen activator. Nonspecific proteolytic activity did not accumulate in the medium during conditioning. The presence of dextran 80 during conditioning of peritoneum reversibly suppressed tissue-bound plasminogen activator activity and reduced plasminogen activator activity in the spent medium. A similar inhibition of peritoneal plasminogen activator was induced by dextran 500, methyl cellulose, and polyvinylpyrrolidone. Dextran, when added to the medium after conditioning, had no direct inhibitory effect on plasminogen activator activity. Dextran did not induce peritoneal production of inhibitor(s) of trypsin, chymotrypsin, or urokinase. On the basis of these findings, two possible mechanisms for the effect of viscous polymers in the reduction of adhesion formation are proposed. These mechanisms consider the importance of peritoneal tissue-type plasminogen activator for removal of fibrin clots and suggest that polymer coating either prevents the shedding of plasminogen activator into the abdominal cavity or reduces the access of fibrin clots to the serosal surfaces. PMID:2459968

  2. Postoperative Peritoneal Adhesions

    PubMed Central

    Ryan, Graeme B.; Grobéty, Jocelyne; Majno, Guido

    1971-01-01

    This paper describes an experimental model of peritoneal adhesions, in the rat, based on two relatively minor accidents that may occur during abdominal surgery in man: drying of the serosa, and bleeding. Drying alone had little effect; drying plus bleeding consistently produced adhesions to the dried area. Fresh blood alone produced adhesions between the three membranous structures [omentum and pelvic fat bodies (PFBs)]. The formation of persistent adhesions required whole blood. Preformed clots above a critical size induced adhesions even without previous serosal injury; they were usually captured by the omentum and PFBs. If all three membranous structures were excised, the clots caused visceral adhesions. The protective role of the omentum, its structure, and the mechanism of omental adhesions, are discussed. These findings are relevant to the pathogenesis of post-operative adhesions in man. ImagesFig 3Fig 4Fig 5Fig 6Fig 7Fig 12Fig 13Fig 1Fig 2Fig 14Fig 15Fig 8Fig 9Fig 10Fig 11 PMID:5315369

  3. ACE2 Decreases Formation and Severity of Angiotensin II-induced Abdominal Aortic Aneurysms

    PubMed Central

    Thatcher, Sean E.; Zhang, Xuan; Howatt, Deborah A.; Yiannikouris, Frederique; Gurley, Susan B.; Ennis, Terri; Curci, John A.; Daugherty, Alan; Cassis, Lisa A.

    2014-01-01

    Objective Angiotensin converting enzyme 2 (ACE2) cleaves angiotensin II (AngII) to form angiotensin-(1-7) (Ang-(1-7)), which generally opposes effects of AngII. AngII infusion into hypercholesterolemic male mice induces formation of abdominal aortic aneurysms (AAAs). This study tests the hypothesis that deficiency of ACE2 promotes AngII-induced AAAs, while ACE2 activation suppresses aneurysm formation. Approach and Results ACE2 protein was detectable by immunostaining in mice and human AAAs. Whole body deficiency of ACE2 significantly increased aortic lumen diameters and external diameters of suprarenal aortas from AngII-infused mice. Conversely, ACE2 deficiency in bone marrow-derived cells had no effect on AngII-induced AAAs. In contrast to AngII-induced AAAs, ACE2 deficiency had no significant effect on external aortic diameters of elastase-induced AAAs. Since ACE2 deficiency promoted AAA formation in AngII-infused mice, we determined if ACE2 activation suppressed AAAs. ACE2 activation by administration of diminazine aceturate (DIZE, 30 mg/kg/day) to Ldlr−/− mice increased kidney ACE2 mRNA abundance and activity and elevated plasma Ang-(1-7) concentrations. Unexpectedly, administration of DIZE significantly reduced total sera cholesterol and VLDL-cholesterol concentrations. Notably, DIZE significantly decreased aortic lumen diameters and aortic external diameters of AngII-infused mice resulting in a marked reduction in AAA incidence (from 73 to 29%). None of these effects of DIZE were observed in the Ace2−/y mice. Conclusions These results demonstrate that ACE2 exerts a modulatory role in AngII-induced AAA formation, and that therapeutic stimulation of ACE2 could be a benefit to reduce AAA expansion and rupture in patients with an activated renin-angiotensin system. PMID:25301841

  4. Neuropilin-2 regulates α6β1 integrin in the formation of focal adhesions and signaling.

    PubMed

    Goel, Hira Lal; Pursell, Bryan; Standley, Clive; Fogarty, Kevin; Mercurio, Arthur M

    2012-01-15

    The neuropilins (NRPs) contribute to the function of cancer cells in their capacity as VEGF receptors. Given that NRP2 is induced in breast cancer and correlates with aggressive disease, we examined the role of NRP2 in regulating the interaction of breast cancer cells with the ECM. Using epithelial cells from breast tumors, we defined NRP2(high) and NRP2(low) populations that differed in integrin expression and adhesion to laminin. Specifically, the NRP2(high) population adhered more avidly to laminin and expressed high levels of the α6β1 integrin than the NRP2(low) population. The NRP2(high) population formed numerous focal adhesions on laminin that were not seen in the NRP2(low) population. These results were substantiated using breast carcinoma cell lines that express NRP2 and α6β1 integrin. Depletion experiments revealed that adhesive strength on laminin but not collagen is dependent on NRP2, and that VEGF is needed for adhesion on laminin. A specific interaction between NRP2 and α6β1 integrin was detected by co-immunoprecipitation. NRP2 is necessary for focal adhesion formation on laminin and for the association of α6β1 integrin with the cytoskeleton. NRP2 also facilitates α6β1-integrin-mediated activation of FAK and Src. Unexpectedly, we discovered that NRP2 is located in focal adhesions on laminin. The mechanism by which NRP2 regulates the interaction of α6β1 integrin with laminin to form focal adhesions involves PKC activation. Together, our data reveal a new VEGF-NRP2 signaling pathway that activates the α6β1 integrin and enables it to form focal adhesions and signal. This pathway is important in the pathogenesis of breast cancer. PMID:22302985

  5. Injury and adhesion formation following ovarian wedge resection with different thermal surgical modalities.

    PubMed

    Bhatta, N; Isaacson, K; Flotte, T; Schiff, I; Anderson, R R

    1993-01-01

    The purpose of this study is to determine the role of bleeding, acute thermal damage, and charring in adhesion formation. Postoperative adhesions were compared following ovarian wedge resection in 48 rabbits using different lasers, electrosurgery, and scalpel. Twelve ovaries were sectioned per modality, in randomized pairs. Acute thermal injury as assessed by histology, bleeding, and charring differed among the modalities used. Adhesions were assessed 4 weeks later, by an investigator completely blinded of the treatment protocol. The adhesion scores were 11.6 +/- 8.0 with pulsed Er:YAG laser; 11.9 +/- 7.5 with scalpel; 8.3 +/- 9.3 with electrocautery; 6.7 +/- 8.8 with a continuous (c.w.) Nd:YAG laser; 5.3 +/- 4.8 with c.w. CO2 laser; 3.1 +/- 2.7 with pulsed CO2 laser; 1.7 +/- 1.8 with pulsed Ho:YAG laser; and 0.8 +/- 1.5 in the control (no resection) group. Ho:YAG, Nd:YAG, and electrocautery were completely hemostatic. Bleeding was minimal with the CO2 lasers. Er:YAG and scalpel caused maximum bleeding, requiring hemostatic measures to prevent exsanguination. Charring occurred with electrocautery, CO2 laser, and Nd:YAG laser. Bleeding and charring correlated with adhesion formation, but the histological depth of thermal damage did not. The Ho:YAG laser is a hemostatic, fiber-optic compatible laser causing significantly fewer adhesions (P < 0.04) than scalpel, electrocautery, Nd:YAG, Er:YAG, and c.w. CO2 lasers. Clinical use of the Ho:YAG laser, and the role of carbonization in promoting adhesions, deserve further study. PMID:8515673

  6. Postoperative Adhesion Formation in a Rabbit Model: Monopolar Electrosurgery Versus Ultrasonic Scalpel

    PubMed Central

    Lazarou, George; Apostol, Radu; Khullar, Poonam; Okonkwo, Linda; Nezhat, Farr

    2015-01-01

    Background and Objectives: To determine if surgery using ultrasonic energy for dissection results in less adhesion formation than monopolar electrosurgical energy in the late (8 weeks) postoperative period. Methods: Injuries were induced in rabbits by using ultrasonic energy on one uterine horn and the adjacent pelvic sidewall and using monopolar energy on the opposite side. Eight weeks postoperatively, the rabbits underwent autopsy and clinical and pathologic scoring of adhesions was performed by blinded investigators. Results: There was no significant difference in clinical adhesion scores between the two modalities. The mean clinical score for monopolar cautery was 1.00 versus 0.88 for the Harmonic device (Ethicon Endo-Surgery, Cincinnati, Ohio) (P = .71). Furthermore, there was no significant difference found in the pathologic adhesion scores between the ultrasonic scalpel and monopolar energy. The mean pathologic score for monopolar electrosurgery was 4.35 versus 3.65 for the Harmonic scalpel (P = .30). Conclusion: Neither monopolar electrosurgery nor ultrasonic dissection is superior in the prevention of adhesion formation in the late postoperative period. PMID:26005316

  7. Subinhibitory Concentrations of Allicin Decrease Uropathogenic Escherichia coli (UPEC) Biofilm Formation, Adhesion Ability, and Swimming Motility.

    PubMed

    Yang, Xiaolong; Sha, Kaihui; Xu, Guangya; Tian, Hanwen; Wang, Xiaoying; Chen, Shanze; Wang, Yi; Li, Jingyu; Chen, Junli; Huang, Ning

    2016-01-01

    Uropathogenic Escherichia coli (UPEC) biofilm formation enables the organism to avoid the host immune system, resist antibiotics, and provide a reservoir for persistent infection. Once the biofilm is established, eradication of the infection becomes difficult. Therefore, strategies against UPEC biofilm are urgently required. In this study, we investigated the effect of allicin, isolated from garlic essential oil, on UPEC CFT073 and J96 biofilm formation and dispersal, along with its effect on UPEC adhesion ability and swimming motility. Sub-inhibitory concentrations (sub-MICs) of allicin decreased UPEC biofilm formation and affected its architecture. Allicin was also capable of dispersing biofilm. Furthermore, allicin decreased the bacterial adhesion ability and swimming motility, which are important for biofilm formation. Real-time quantitative polymerase chain reaction (RT-qPCR) revealed that allicin decreased the expression of UPEC type 1 fimbriae adhesin gene fimH. Docking studies suggested that allicin was located within the binding pocket of heptyl α-d-mannopyrannoside in FimH and formed hydrogen bonds with Phe1 and Asn135. In addition, allicin decreased the expression of the two-component regulatory systems (TCSs) cognate response regulator gene uvrY and increased the expression of the RNA binding global regulatory protein gene csrA of UPEC CFT073, which is associated with UPEC biofilm. The findings suggest that sub-MICs of allicin are capable of affecting UPEC biofilm formation and dispersal, and decreasing UPEC adhesion ability and swimming motility. PMID:27367677

  8. Subinhibitory Concentrations of Allicin Decrease Uropathogenic Escherichia coli (UPEC) Biofilm Formation, Adhesion Ability, and Swimming Motility

    PubMed Central

    Yang, Xiaolong; Sha, Kaihui; Xu, Guangya; Tian, Hanwen; Wang, Xiaoying; Chen, Shanze; Wang, Yi; Li, Jingyu; Chen, Junli; Huang, Ning

    2016-01-01

    Uropathogenic Escherichia coli (UPEC) biofilm formation enables the organism to avoid the host immune system, resist antibiotics, and provide a reservoir for persistent infection. Once the biofilm is established, eradication of the infection becomes difficult. Therefore, strategies against UPEC biofilm are urgently required. In this study, we investigated the effect of allicin, isolated from garlic essential oil, on UPEC CFT073 and J96 biofilm formation and dispersal, along with its effect on UPEC adhesion ability and swimming motility. Sub-inhibitory concentrations (sub-MICs) of allicin decreased UPEC biofilm formation and affected its architecture. Allicin was also capable of dispersing biofilm. Furthermore, allicin decreased the bacterial adhesion ability and swimming motility, which are important for biofilm formation. Real-time quantitative polymerase chain reaction (RT-qPCR) revealed that allicin decreased the expression of UPEC type 1 fimbriae adhesin gene fimH. Docking studies suggested that allicin was located within the binding pocket of heptyl α-d-mannopyrannoside in FimH and formed hydrogen bonds with Phe1 and Asn135. In addition, allicin decreased the expression of the two-component regulatory systems (TCSs) cognate response regulator gene uvrY and increased the expression of the RNA binding global regulatory protein gene csrA of UPEC CFT073, which is associated with UPEC biofilm. The findings suggest that sub-MICs of allicin are capable of affecting UPEC biofilm formation and dispersal, and decreasing UPEC adhesion ability and swimming motility. PMID:27367677

  9. Severe inflammatory reaction induced by peritoneal trauma is the key driving mechanism of postoperative adhesion formation

    PubMed Central

    2011-01-01

    Background Many factors have been put forward as a driving mechanism of surgery-triggered adhesion formation (AF). In this study, we underline the key role of specific surgical trauma related with open surgery (OS) and laparoscopic (LS) conditions in postoperative AF and we aimed to study peritoneal tissue inflammatory reaction (TIR), remodelling specific complications of open surgery (OS) versus LS and subsequently evaluating AF induced by these conditions. Methods A prospective randomized study was done in 80 anaesthetised female Wistar rats divided equally into 2 groups. Specific traumatic OS conditions were induced by midline incision line (MIL) extension and tissue drying and specific LS conditions were remodelled by intraperitoneal CO2 insufflation at the 10 cm of water. TIR was evaluated at the 24th, 72nd, 120th and 168th hour by scoring scale. Statistical analysis was performed by the non-parametric t test and two-way ANOVA using Bonferroni post-tests. Results More pronounced residual TIR was registered after OS than after LS. There were no significant TIR interactions though highly significant differences were observed between the OS and LS groups (p < 0.0001) with regard to surgical and time factors. The TIR change differences between the OS and LS groups were pronounced with postoperative time p < 0.05 at the 24th and 72nd; p < 0.01 - 120th and p < 0.001 - 168th hrs. Adhesion free wounds were observed in 20.0 and 31.0% of cases after creation of OS and LS conditions respectively; with no significant differences between these values (p > 0.05). However larger adhesion size (41.67 ± 33.63) was observed after OS in comparison with LS (20.31 ± 16.38). The upper-lower 95% confidential limits ranged from 60.29 to 23.04 and from 29.04 to 11.59 respectively after OS and LS groups with significant differences (p = 0.03). Analogous changes were observed in adhesion severity values. Subsequently, severe TIR parameters were followed by larger sizes of severe

  10. Cytokine amplification and macrophage effector functions in aortic inflammation and abdominal aortic aneurysm formation.

    PubMed

    Ijaz, Talha; Tilton, Ronald G; Brasier, Allan R

    2016-08-01

    On April 29, 2015, Son and colleagues published an article entitled "Granulocyte macrophage colony-stimulating factor (GM-CSF) is required for aortic dissection/intramural haematoma" in Nature Communications. The authors observed that the heterozygous Kruppel-like transcription factor 6 (KLF6) deficiency or absence of myeloid-specific KLF6 led to upregulation of macrophage GM-CSF expression, promoted the development of aortic hematoma/dissection, and stimulated abdominal aortic aneurysm (AAA) formation when the vessel wall was subjected to an inflammatory stimulus. The additional findings of increased adventitial fibrotic deposition, marked infiltration of macrophages, and increased expression of matrix metalloprotease-9 (MMP-9) and IL-6 were blocked with neutralizing GM-CSF antibodies, or recapitulated in normal mice with excess GM-CSF administration. The authors concluded that GM-CSF is a key regulatory molecule in the development of AAA and further suggested that activation of GM-CSF is independent of the transforming growth factor β (TGFβ)-Smad pathway associated with the Marfan aortic pathology. In this perspective, we expand on this mechanism, drawing from previous studies implicating a similar essential role for IL-6 signaling in macrophage activation, Th17 expansion and aortic dissections. We propose a sequential "two-hit" model of vascular inflammation involving initial vascular injury followed by recruitment of Ly6C(hi) macrophages. Aided by fibroblast interactions inflammatory macrophages produce amplification of IL-6 and GM-CSF expression that converge on a common, pathogenic Janus kinase (JAK)-signal transducers and activations of transcription 3 (STAT3) signaling pathway. This pathway stimulates effector functions of macrophages, promotes differentiation of Th17 lymphocytes and enhances matrix metalloproteinase expression, ultimately resulting in deterioration of vascular wall structural integrity. Further research evaluating the impact of

  11. Cytokine amplification and macrophage effector functions in aortic inflammation and abdominal aortic aneurysm formation

    PubMed Central

    Ijaz, Talha; Tilton, Ronald G.

    2016-01-01

    On April 29, 2015, Son and colleagues published an article entitled “Granulocyte macrophage colony-stimulating factor (GM-CSF) is required for aortic dissection/intramural haematoma” in Nature Communications. The authors observed that the heterozygous Kruppel-like transcription factor 6 (KLF6) deficiency or absence of myeloid-specific KLF6 led to upregulation of macrophage GM-CSF expression, promoted the development of aortic hematoma/dissection, and stimulated abdominal aortic aneurysm (AAA) formation when the vessel wall was subjected to an inflammatory stimulus. The additional findings of increased adventitial fibrotic deposition, marked infiltration of macrophages, and increased expression of matrix metalloprotease-9 (MMP-9) and IL-6 were blocked with neutralizing GM-CSF antibodies, or recapitulated in normal mice with excess GM-CSF administration. The authors concluded that GM-CSF is a key regulatory molecule in the development of AAA and further suggested that activation of GM-CSF is independent of the transforming growth factor β (TGFβ)-Smad pathway associated with the Marfan aortic pathology. In this perspective, we expand on this mechanism, drawing from previous studies implicating a similar essential role for IL-6 signaling in macrophage activation, Th17 expansion and aortic dissections. We propose a sequential “two-hit” model of vascular inflammation involving initial vascular injury followed by recruitment of Ly6Chi macrophages. Aided by fibroblast interactions inflammatory macrophages produce amplification of IL-6 and GM-CSF expression that converge on a common, pathogenic Janus kinase (JAK)-signal transducers and activations of transcription 3 (STAT3) signaling pathway. This pathway stimulates effector functions of macrophages, promotes differentiation of Th17 lymphocytes and enhances matrix metalloproteinase expression, ultimately resulting in deterioration of vascular wall structural integrity. Further research evaluating the impact of

  12. Influence of Aae Autotransporter Protein on Adhesion and Biofilm Formation by Aggregatibacter actinomycetemcomitans.

    PubMed

    Nunes, Ana Carla Robatto; Longo, Priscila Larcher; Mayer, Marcia Pinto Alves

    2016-01-01

    The periodontopathogen Aggregatibacter actinomycetemcomitans colonizes oral cavity by binding to and invading epithelial cells as well as by participating in biofilms formed on hard surfaces. Aae, an autotransporter protein, is implicated in bacterial adhesion to epithelial cells. Due to the multiple functions of bacterial autotransporter proteins, this study aimed to evaluate the role of aae in A. actinomycetemcomitans ability to adhere to both saliva-coated hydroxyapatite (SHA) and biofilm. An aae null mutant was constructed. Its hydrophobic properties as well as its ability to adhere to epithelial cells, SHA and to form biofilm were evaluated and compared with the parental strain, A. actinomycetemcomitans VT1169. The aae null mutant showed reduced hydrophobicity, as well as decreased binding to SHA and biofilm formation compared to the parental strain. These data suggest that aae mediates A. actinomycetemcomitans adhesion to epithelial cells and may be involved in biofilm formation and interaction with adsorbed salivary proteins. PMID:27224556

  13. Physicochemical analysis of initial adhesion and biofilm formation of Methanosarcina barkeri on polymer support material.

    PubMed

    Nguyen, Vi; Karunakaran, Esther; Collins, Gavin; Biggs, Catherine A

    2016-07-01

    The retention of selective biofilms of Methanosarcina species within anaerobic digesters could reduce start-up times and enhance the efficiency of the process in treating high-strength domestic sewage. The objective of the study was to examine the effect of the surface characteristics of six common polymer support materials on the initial adhesion of the model methanogen, Methanosarcina barkeri, and to assess the potential of these support materials as selective biofilm carriers. Results from both the initial adhesion tests and extended DLVO (xDLVO) model correlated with each other, with PVC (12% surface coverage/mm(2)), PTFE (6% surface coverage/mm(2)), and PP (6% surface coverage/mm(2)), shown to be the better performing support materials for initial adhesion, as well as subsequent biofilm formation by M. barkeri after 72h. Experimental results of these three support materials showed that the type of material strongly influenced the extent of adhesion from M. barkeri (p<0.0001), and the xDLVO model was able to explain the results in these environmental conditions. Therefore, DLVO physicochemical forces were found to be influential on the initial adhesion of M. barkeri. Scanning electron microscopy suggested that production of extracellular polymeric substances (EPS) from M. barkeri could facilitate further biofilm development. This study highlights the potential of using the xDLVO model to rapidly identify suitable materials for the selective adhesion of M. barkeri, which could be beneficial in both the start-up and long-term phases of anaerobic digestion. PMID:27038917

  14. Formation of semi-dilute adhesion domains driven by weak elasticity-mediated interactions.

    PubMed

    Dharan, Nadiv; Farago, Oded

    2016-08-21

    Cell-cell adhesion is established by specific binding of receptor and ligand proteins anchored in the cell membranes. The adhesion bonds attract each other and often aggregate into large clusters that are central to many biological processes. One possible origin of attractive interactions between adhesion bonds is the elastic response of the membranes to their deformation by the bonds. Here, we analyze these elasticity-mediated interactions using a novel mean-field approach. Our analysis of systems at different densities of bonds, ϕ, reveals that the phase diagram, i.e., the binodal and spinodal lines, exhibit a nearly universal behavior when the temperature T is plotted against the scaled density x = ϕξ(2), where ξ is the linear size of the membrane's region affected by the presence of a single isolated bond. The critical point (ϕc , Tc) is located at very low densities, and slightly below Tc we identify phase coexistence between two low-density phases. Dense adhesion domains are observed only when the height by which the bonds deform the membranes, h0, is much larger than their thermal roughness, Δ, which occurs at very low temperatures T≪Tc. We, thus, conclude that the elasticity-mediated interactions are weak and cannot be regarded as responsible for the formation of dense adhesion domains. The weakness of the elasticity-mediated effect and its relevance to dilute systems only can be attributed to the fact that the membrane's elastic energy saturates in the semi-dilute regime, when the typical spacing between the bonds r≳ξ, i.e., for x≲ 1. Therefore, at higher densities, only the mixing entropy of the bonds (which always favors uniform distributions) is thermodynamically relevant. We discuss the implications of our results for the question of immunological synapse formation, and demonstrate that the elasticity-mediated interactions may be involved in the aggregation of these semi-dilute membrane domains. PMID:27426284

  15. 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

  16. 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

    2015-01-01

    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

  17. Quantitative Characterization of the Influence of the Nanoscale Morphology of Nanostructured Surfaces on Bacterial Adhesion and Biofilm Formation

    PubMed Central

    Singh, Ajay Vikram; Vyas, Varun; Patil, Rajendra; Sharma, Vimal; Scopelliti, Pasquale Emanuele; Bongiorno, Gero; Podestà, Alessandro; Lenardi, Cristina; Gade, Wasudev Namdev; Milani, Paolo

    2011-01-01

    Bacterial infection of implants and prosthetic devices is one of the most common causes of implant failure. The nanostructured surface of biocompatible materials strongly influences the adhesion and proliferation of mammalian cells on solid substrates. The observation of this phenomenon has led to an increased effort to develop new strategies to prevent bacterial adhesion and biofilm formation, primarily through nanoengineering the topology of the materials used in implantable devices. While several studies have demonstrated the influence of nanoscale surface morphology on prokaryotic cell attachment, none have provided a quantitative understanding of this phenomenon. Using supersonic cluster beam deposition, we produced nanostructured titania thin films with controlled and reproducible nanoscale morphology respectively. We characterized the surface morphology; composition and wettability by means of atomic force microscopy, X-ray photoemission spectroscopy and contact angle measurements. We studied how protein adsorption is influenced by the physico-chemical surface parameters. Lastly, we characterized Escherichia coli and Staphylococcus aureus adhesion on nanostructured titania surfaces. Our results show that the increase in surface pore aspect ratio and volume, related to the increase of surface roughness, improves protein adsorption, which in turn downplays bacterial adhesion and biofilm formation. As roughness increases up to about 20 nm, bacterial adhesion and biofilm formation are enhanced; the further increase of roughness causes a significant decrease of bacterial adhesion and inhibits biofilm formation. We interpret the observed trend in bacterial adhesion as the combined effect of passivation and flattening effects induced by morphology-dependent protein adsorption. Our findings demonstrate that bacterial adhesion and biofilm formation on nanostructured titanium oxide surfaces are significantly influenced by nanoscale morphological features. The

  18. Kank2 activates talin, reduces force transduction across integrins and induces central adhesion formation.

    PubMed

    Sun, Zhiqi; Tseng, Hui-Yuan; Tan, Steven; Senger, Fabrice; Kurzawa, Laetitia; Dedden, Dirk; Mizuno, Naoko; Wasik, Anita A; Thery, Manuel; Dunn, Alexander R; Fässler, Reinhard

    2016-09-01

    Integrin-based adhesions play critical roles in cell migration. Talin activates integrins and flexibly connects integrins to the actomyosin cytoskeleton, thereby serving as a 'molecular clutch' that transmits forces to the extracellular matrix to drive cell migration. Here we identify the evolutionarily conserved Kank protein family as novel components of focal adhesions (FAs). Kank proteins accumulate at the lateral border of FAs, which we term the FA belt, and in central sliding adhesions, where they directly bind the talin rod domain through the Kank amino-terminal (KN) motif and induce talin and integrin activation. In addition, Kank proteins diminish the talin-actomyosin linkage, which curbs force transmission across integrins, leading to reduced integrin-ligand bond strength, slippage between integrin and ligand, central adhesion formation and sliding, and reduced cell migration speed. Our data identify Kank proteins as talin activators that decrease the grip between the integrin-talin complex and actomyosin to regulate cell migration velocity. PMID:27548916

  19. Pathophysiology and prevention of postoperative peritoneal adhesions

    PubMed Central

    Arung, Willy; Meurisse, Michel; Detry, Olivier

    2011-01-01

    Peritoneal adhesions represent an important clinical challenge in gastrointestinal surgery. Peritoneal adhesions are a consequence of peritoneal irritation by infection or surgical trauma, and may be considered as the pathological part of healing following any peritoneal injury, particularly due to abdominal surgery. The balance between fibrin deposition and degradation is critical in determining normal peritoneal healing or adhesion formation. Postoperative peritoneal adhesions are a major cause of morbidity resulting in multiple complications, many of which may manifest several years after the initial surgical procedure. In addition to acute small bowel obstruction, peritoneal adhesions may cause pelvic or abdominal pain, and infertility. In this paper, the authors reviewed the epidemiology, pathogenesis and various prevention strategies of adhesion formation, using Medline and PubMed search. Several preventive agents against postoperative peritoneal adhesions have been investigated. Their role aims in activating fibrinolysis, hampering coagulation, diminishing the inflammatory response, inhibiting collagen synthesis or creating a barrier between adjacent wound surfaces. Their results are encouraging but most of them are contradictory and achieved mostly in animal model. Until additional findings from future clinical researches, only a meticulous surgery can be recommended to reduce unnecessary morbidity and mortality rates from these untoward effects of surgery. In the current state of knowledge, pre-clinical or clinical studies are still necessary to evaluate the effectiveness of the several proposed prevention strategies of postoperative peritoneal adhesions. PMID:22147959

  20. 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.

  1. Mg(2+)/Ca(2+) promotes the adhesion of marine bacteria and algae and enhances following biofilm formation in artificial seawater.

    PubMed

    He, Xiaoyan; Wang, Jinpeng; Abdoli, Leila; Li, Hua

    2016-10-01

    Adhesion of microorganisms in the marine environment is essential for initiation and following development of biofouling. A variety of factors play roles in regulating the adhesion. Here we report the influence of Ca(2+) and Mg(2+) in artificial seawater on attachment and colonization of Bacillus sp., Chlorella and Phaeodactylum tricornutum on silicon wafer. Extra addition of the typical divalent cations in culturing solution gives rise to significantly enhanced adhesion of the microorganisms. Mg(2+) and Ca(2+) affect the adhesion of Bacillus sp. presumably by regulating aggregation and formation of extracellular polymeric substances (EPS). The ions alter quantity and types of the proteins in EPS, in turn affecting subsequent adhesion. However, it is noted that Mg(2+) promotes adhesion of Chlorella likely by regulating EPS formation and polysaccharide synthesis. Ca(2+) plays an important role in protein expression to enhance the adhesion of Chlorella. For Phaeodactylum tricornutum, Ca(2+) expedites protein synthesis for enhanced adhesion. The results shed some light on effective ways of utilizing divalent cations to mediate formation of biofilms on the marine structures for desired performances. PMID:27362920

  2. Mechanism of platelet adhesion to von Willebrand factor and microparticle formation under high shear stress

    PubMed Central

    Reininger, Armin J.; Heijnen, Harry F. G.; Schumann, Hannah; Specht, Hanno M.; Schramm, Wolfgang; Ruggeri, Zaverio M.

    2006-01-01

    We describe here the mechanism of platelet adhesion to immobilized von Willebrand factor (VWF) and subsequent formation of platelet-derived microparticles mediated by glycoprotein Ibα (GPIbα) under high shear stress. As visualized in whole blood perfused in a flow chamber, platelet attachment to VWF involved one or few membrane areas of 0.05 to 0.1 μm2 that formed discrete adhesion points (DAPs) capable of resisting force in excess of 160 pN. Under the influence of hydrodynamic drag, membrane tethers developed between the moving platelet body and DAPs firmly adherent to immobilized VWF. Continued stretching eventually caused the separation of many such tethers, leaving on the surface tube-shaped or spherical microparticles with a diameter as low as 50 to 100 nm. Adhesion receptors (GPIbα, αIIbβ3) and phosphatidylserine were expressed on the surface of these microparticles, which were procoagulant. Shearing platelet-rich plasma at the rate of 10 000 s–1 in a cone-and-plate viscosimeter increased microparticle counts up to 55-fold above baseline. Blocking the GPIb-VWF interaction abolished microparticle generation in both experimental conditions. Thus, a biomechanical process mediated by GPIbα-VWF bonds in rapidly flowing blood may not only initiate platelet arrest onto reactive vascular surfaces but also generate procoagulant microparticles that further enhance thrombus formation. PMID:16449527

  3. Integrin-Associated Complexes Form Hierarchically with Variable Stoichiometry during Nascent Adhesion Formation

    PubMed Central

    Bachir, Alexia I.; Zareno, Jessica; Moissoglu, Konstadinos; Plow, Edward; Gratton, Enrico; Horwitz, Alan R.

    2014-01-01

    Summary Background A complex network of putative molecular interactions underlies the architecture and function of cell-matrix adhesions. Most of these interactions are implicated from co-immunoprecipitation studies using expressed components; but few have been demonstrated or characterized functionally in living cells. Results We introduce fluorescence fluctuation methods to determine, at high spatial and temporal resolution, ‘when’ and ‘where’ molecular complexes form and their stoichiometry in nascent adhesions (NAs). We focus on integrin-associated molecules implicated in integrin-activation and in the integrin-actin linkage in NAs and show that these molecules form integrin containing complexes hierarchically within the adhesion itself. Integrin and kindlin reside in a molecular complex as soon as adhesions are visible; talin, while also present early, associates with the integrin-kindlin complex only after NAs have formed and in response to myosin II activity. Furthermore, talin and vinculin association precedes the formation of the integrin-talin complex. Finally, α-actinin enters NAs periodically and in clusters that transiently associate with integrins. The absolute number and stoichiometry of these molecules varies among the molecules studied and changes as adhesions mature. Conclusions These observations suggest a working model for NA assembly, whereby transient α-actinin- integrin complexes help nucleate NAs within the lamellipodium. Subsequently integrin complexes containing kindlin, but not talin, emerge. Once NAs have formed, myosin II activity promotes talin association with the integrin-kindlin complex in a stoichiometry consistent with each talin molecule linking two integrin-kindlin complexes. PMID:25088556

  4. Boronate Complex Formation with Dopa Containing Mussel Adhesive Protein Retards pH-Induced Oxidation and Enables Adhesion to Mica

    PubMed Central

    Israelachvili, Jacob N.; Chen, Yunfei; Waite, J. Herbert

    2014-01-01

    The biochemistry of mussel adhesion has inspired the design of surface primers, adhesives, coatings and gels for technological applications. These mussel-inspired systems often focus on incorporating the amino acid 3,4-dihydroxyphenyl-L-alanine (Dopa) or a catecholic analog into a polymer. Unfortunately, effective use of Dopa is compromised by its susceptibility to auto-oxidation at neutral pH. Oxidation can lead to loss of adhesive function and undesired covalent cross-linking. Mussel foot protein 5 (Mfp-5), which contains ∼30 mole % Dopa, is a superb adhesive under reducing conditions but becomes nonadhesive after pH-induced oxidation. Here we report that the bidentate complexation of borate by Dopa to form a catecholato-boronate can be exploited to retard oxidation. Although exposure of Mfp-5 to neutral pH typically oxidizes Dopa, resulting in a>95% decrease in adhesion, inclusion of borate retards oxidation at the same pH. Remarkably, this Dopa-boronate complex dissociates upon contact with mica to allow for a reversible Dopa-mediated adhesion. The borate protection strategy allows for Dopa redox stability and maintained adhesive function in an otherwise oxidizing environment. PMID:25303409

  5. Adhesions and Adhesiolysis: The Role of Laparoscopy

    PubMed Central

    Kavic, Suzanne M.

    2002-01-01

    Background: Adhesions commonly result from abdominal and pelvic surgical procedures and may result in intestinal obstruction, infertility, chronic pain, or complicate subsequent operations. Laparoscopy produces less peritoneal trauma than does conventional laparotomy and may result in decreased adhesion formation. We present a review of the available data on laparoscopy and adhesion formation, as well as laparoscopic adhesiolysis. We also review current adjuvant techniques that may be used by practicing laparoscopists to prevent adhesion formation. Database: A Medline search using “adhesions,” “adhesiolysis,” and “laparoscopy” as key words was performed for English-language articles. Further references were obtained through cross-referencing the bibliography cited in each work. Discussion: The majority of studies indicate that laparoscopy may reduce postoperative adhesion formation relative to laparotomy. However, laparoscopy by itself does not appear to eliminate adhesions completely. A variety of adjuvant materials are available to surgeons, and the most recent investigation has demonstrated significant potential for intraperitoneal barriers. Newer technologies continue to evolve and should result in clinically relevant reductions in adhesion formation. PMID:12113430

  6. Adhesion and biofilm formation in artificial saliva and susceptibility of yeasts isolated from chronic kidney patients undergoing haemodialysis.

    PubMed

    Queiroz, Paula Assis; Godoy, Janine Silva Ribeiro; Mendonça, Patrícia de Souza Bonfim; Pedroso, Raíssa Bocchi; Svidzinski, Terezinha Inez Estivalet; Negri, Melyssa

    2015-09-01

    Yeasts of the genera Candida and Saccharomyces are opportunist pathogens and cause oral lesions, especially in immunocompromised patients. This study assessed yeasts isolated from chronic kidney patients undergoing haemodialysis for their adhesion capacity, biofilm formation and susceptibility to antifungal agents. Ten isolates of Candida spp. and one isolate of Saccharomyces cerevisiae were tested for adhesion to buccal epithelial cells (BECs), adhesion and formation of biofilm in artificial saliva and their susceptibility profile to antifungal agents. Adhesion and biofilm formation were undertaken in polystyrene plates with artificial saliva, whilst susceptibility to antifungal agents was evaluated by broth microdilution. Candida parapsilosis had the highest adhesion index in BECs (154.55 ± 22.13) and Candida rugosa was the species with the highest adhesion capacity (18 398  Abs cm(-2)) in abiotic surface with artificial saliva. Candida albicans provided the greatest biofilm formation (2035  Abs cm(-2) ± 0.09) but was revealed to be susceptible to the five antifungal agents under analysis. However, some non-albicans Candida isolates showed a lower susceptibility for the antifungal agents itraconazole, fluconazole and voriconazole. All of the species were sensitive to amphotericin B and nystatin. The current analysis showed that yeasts isolated from the mouth of chronic kidney patients undergoing haemodialysis varied significantly with regard to their capacity for adherence, biofilm formation and susceptibility to antifungal agents, underscoring the high virulence of non-albicans Candida species. PMID:26297016

  7. An unusual cause of chronic abdominal pain after laparoscopic Roux en Y gastric bypass: Case report of a penetrating fish bone causing adhesions at the biliary-digestive junction resulting in partial obstruction and chronic symptoms

    PubMed Central

    Ochieng, Vincent; Hendrickx, Leo; Valk, Jody

    2016-01-01

    Background The management of chronic abdominal pain after laparoscopic Roux-en-Y gastric bypass (LRYGP) is complex and challenging. Foreign body intestinal perforation including that caused by fish bones has previously been reported in the literature and if clinically unrecognized, can cause significant morbidity and mortality. Fish bone perforation as a cause of chronic abdominal pain after LRYGP has rarely been reported. Summary The unusual case of a 54 year old female presenting with recurrent episodes of postprandial pain 2 years after LRYGP is reported. Previous radiological and endoscopic investigations did not reveal any abnormality and after the most recent clinical presentation, a laparoscopic exploration was performed. A protruding fish bone at the biliary-digestive junction was discovered intra-operatively and successfully extracted. Dense adhesions between the involved intestinal loops were lysed in an attempt to improve intestinal transit and subsequently relieve post-prandial pain. Conclusion This case highlights the possibility of a missed fish bone perforation causing chronic postprandial abdominal pain and discomfort in a patient with a Roux-en-Y gastric bypass anatomy. Foreign body perforation is a rare cause of abdominal pain after gastric bypass that should be considered when evaluating chronic abdominal pain symptoms after LRYGP. PMID:27107305

  8. 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

  9. Aggregatibacter actinomycetemcomitans arcB influences hydrophobic properties, biofilm formation and adhesion to hydroxyapatite

    PubMed Central

    Longo, PL; Ota-Tsuzuki, C; Nunes, ACR; Fernandes, BL; Mintz, K; Fives-Taylor, P; Mayer, MPA

    2009-01-01

    The regulation of gene expression in the oral pathogen Aggregatibacter actinomycetemcomitans is still not fully elucidated. ArcAB is a two-component system which allows facultative anaerobic bacteria to sense various respiratory growth conditions and adapt their gene expression accordingly.This study investigated in A. actinomycetemcomitans the role of ArcB on the regulation of biofilm formation, adhesion to saliva coated hydroxyapatite (SHA) and the hydrophobic properties of the cell. These phenotypic traits were determined for an A. actinomycetemcomitans arcB deficient type and a wild type strain. Differences in hydrophobic properties were shown at early and late exponential growth phases under microaerobic incubation and at late exponential phase under anaerobiosis.The arcB mutant formed less biofilm than the wild type strain when grown under anaerobic incubation, but displayed higher biofilm formation activity under microaerobic conditions. The adherence to SHA was significantly lower in the mutant when compared with the wild type strain. These results suggest that the transmembrane sensor kinase ArcB, in A. actinomycetemcomitans, senses redox growth conditions and regulates the expression of surface components of the bacterial cell related to biofilm formation and adhesion to saliva coated surfaces. PMID:24031399

  10. The EP3 Agonist Sulprostone Enhances Platelet Adhesion But Not Thrombus Formation Under Flow Conditions.

    PubMed

    Pasterk, Lisa; Philipose, Sonia; Eller, Kathrin; Marsche, Gunther; Heinemann, Akos; Schuligoi, Rufina

    2015-01-01

    Platelets express the EP2, EP3 and EP4 receptors. Prostaglandin (PG) E2 has a biphasic effect on platelets. Low concentrations of PGE2 enhance platelet aggregation through the activation of the EP3 receptors, while at high concentrations it attenuates aggregation via the EP4 receptor. Consequently, EP3 receptor inhibition was shown to inhibit artherothrombosis, but had no influence on bleeding time in vivo. In this study, we investigated the role of the EP3 receptor in adhesion and thrombus formation under flow conditions in vitro. The EP3 agonist sulprostone caused an increase in the adhesion of washed platelets to fibrinogen as well as to collagen under low shear stress, an effect that was blocked by the EP3 antagonist L-798106. In contrast, when whole blood was perfused over collagen-coated surfaces, sulprostone did not enhance binding and thrombus formation of platelets on collagen; at high concentrations it even attenuated this response. We conclude that in more physiological models of thrombus formation, the role for EP3 receptors is limited, indirectly suggesting that the primary action of PGE2 in haemostasis might be an inhibitory one. PMID:26228833

  11. 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

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

    PubMed

    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

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

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

    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.

  14. Digital oedema, adhesion formation and resistance to digital motion after primary flexor tendon repair.

    PubMed

    Cao, Y; Chen, C H; Wu, Y F; Xu, X F; Xie, R G; Tang, J B

    2008-12-01

    The development of digital oedema, adhesion formation, and resistance to digital motion at days 0, 3, 5, 7, 9 and 14 after primary flexor tendon repairs using 102 long toes of 51 Leghorn chickens was studied. Oedema presented as tissue swelling from days 3 to 7, which peaked at day 3. After day 7, oedema was manifest as hardening of subcutaneous tissue. The degree of digital swelling correlated with the resistance to tendon motion between days 3 and 7. At day 9, granulation tissues were observed around the tendon and loose adhesions were observed at day 14. Resistance to digital motion increased significantly from day 0 to day 3, but did not increase between days 3 and 9. The early postoperative changes appear to have three stages: initial (days 0-3, increasing resistance with development of oedema), delayed (days 4-7, higher resistance with continuing oedema) and late (after day 7-9, hardening of subcutaneous tissue with development of adhesions). PMID:18936126

  15. Autocrine netrin function inhibits glioma cell motility and promotes focal adhesion formation.

    PubMed

    Jarjour, Andrew A; Durko, Margaret; Luk, Tamarah L; Marçal, Nathalie; Shekarabi, Masoud; Kennedy, Timothy E

    2011-01-01

    Deregulation of mechanisms that control cell motility plays a key role in tumor progression by promoting tumor cell dissemination. Secreted netrins and their receptors, Deleted in Colorectal Cancer (DCC), neogenin, and the UNC5 homologues, regulate cell and axon migration, cell adhesion, and tissue morphogenesis. Netrin and netrin receptor expression have previously been shown to be disrupted in invasive tumors, including glioblastoma. We determined that the human glioblastoma cell lines U87, U343, and U373 all express neogenin, UNC5 homologues, and netrin-1 or netrin-3, but only U87 cells express DCC. Using transfilter migration assays, we demonstrate DCC-dependent chemoattractant migration of U87 cells up a gradient of netrin-1. In contrast, U343 and U373 cells, which do not express DCC, were neither attracted nor repelled. Ectopic expression of DCC by U343 and U373 cells resulted in these cells becoming competent to respond to a gradient of netrin-1 as a chemoattractant, and also slowed their rate of spontaneous migration. Here, in addition to netrins' well-characterized chemotropic activity, we demonstrate an autocrine function for netrin-1 and netrin-3 in U87 and U373 cells that slows migration. We provide evidence that netrins promote the maturation of focal complexes, structures associated with cell movement, into focal adhesions. Consistent with this, netrin, DCC, and UNC5 homologues were associated with focal adhesions, but not focal complexes. Disrupting netrin or DCC function did not alter cell proliferation or survival. Our findings provide evidence that DCC can slow cell migration, and that neogenin and UNC5 homologues are not sufficient to substitute for DCC function in these cells. Furthermore, we identify a role for netrins as autocrine inhibitors of cell motility that promote focal adhesion formation. These findings suggest that disruption of netrin signalling may disable a mechanism that normally restrains inappropriate cell migration. PMID

  16. Role of focal adhesions and mechanical stresses in the formation and progression of the lamellipodium-lamellum interface [corrected].

    PubMed

    Shemesh, Tom; Verkhovsky, Alexander B; Svitkina, Tatyana M; Bershadsky, Alexander D; Kozlov, Michael M

    2009-09-01

    Actin network in the front part of a moving cell is organized into a lamellipodium and a lamellum. A distinct lamellipodium-lamellum interface is associated with focal adhesions and consists of a series of arclike segments linking neighboring focal adhesions in the front row. The interface advances by leaping onto new rows of focal adhesions maturating underneath the lamellipodium. We propose a mechanism of the lamellipodium-lamellum boundary generation, shape formation, and progression based on the elastic stresses generated in the lamellipodial actin gel by its friction against the focal adhesions. The crucial assumption of the model is that stretching stresses trigger actin gel disintegration. We compute the stress distribution throughout the actin gel and show that the gel-disintegrating stresses drive formation of a gel boundary passing through the row of focal adhesions. Our computations recover the lamellipodium-lamellum boundary shapes detected in cells and predict the mode of the boundary transition to the row of the newly maturing focal adhesions in agreement with the experimental observations. The model fully accounts for the current phenomenology of the lamellipodium-lamellum interface formation and advancing, and makes experimentally testable predictions on the dependence of these phenomena on the sizes of the focal adhesions, the character of the focal adhesion distribution on the substrate, and the velocity of the actin retrograde flow with respect to the focal adhesions. The phase diagram resulting from the model provides a background for quantitative classification of different cell types with respect to their ability to form a lamellipodium-lamellum interface. In addition, the model suggests a mechanism of nucleation of the dorsal and arclike actin bundles found in the lamellum. PMID:19720013

  17. 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

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

    PubMed Central

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

    2013-01-01

    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 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. Finally, the synergistic efficacy of NO and silver sulfadiazine against C. albicans adhered fungal cells and biofilms is reported with increased killing and biofilm inhibition over NO alone. PMID:21082455

  19. Dipeptidyl Peptidase-4 Inhibitor Decreases Abdominal Aortic Aneurysm Formation through GLP-1-Dependent Monocytic Activity in Mice

    PubMed Central

    Lu, Hsin Ying; Huang, Chun Yao; Shih, Chun Ming; Chang, Wei Hung; Tsai, Chein Sung; Lin, Feng Yen; Shih, Chun Che

    2015-01-01

    Abdominal aortic aneurysm (AAA) is a life-threatening situation affecting almost 10% of elders. There has been no effective medication for AAA other than surgical intervention. Dipeptidyl peptidase-4 (DPP-4) inhibitors have been shown to have a protective effect on cardiovascular disease. Whether DPP-4 inhibitors may be beneficial in the treatment of AAA is unclear. We investigated the effects of DPP-4 inhibitor sitagliptin on the angiotensin II (Ang II)-infused AAA formation in apoE-deficient (apoE-/-) mice. Mice with induced AAA were treated with placebo or 2.5, 5 or 10 mg/kg/day sitagliptin. Ang II-infused apoE-/- mice exhibited a 55.6% incidence of AAA formation, but treatment with sitagliptin decreased AAA formation. Specifically, administered sitagliptin in Ang II-infused mice exhibited decreased expansion of the suprarenal aorta, reduced elastin lamina degradation of the aorta, and diminished vascular inflammation by macrophage infiltration. Treatment with sitagliptin decreased gelatinolytic activity and apoptotic cells in aorta tissues. Sitaglipitn, additionally, was associated with increased levels of plasma active glucagon-like peptide-1 (GLP-1). In vitro studies, GLP-1 decreased reactive oxygen species (ROS) production, cell migration, and MMP-2 as well as MMP-9 activity in Ang II-stimulated monocytic cells. The results conclude that oral administration of sitagliptin can prevent abdominal aortic aneurysm formation in Ang II-infused apoE-/-mice, at least in part, by increasing of GLP-1 activity, decreasing MMP-2 and MMP-9 production from macrophage infiltration. The results indicate that sitagliptin may have therapeutic potential in preventing the development of AAA. PMID:25876091

  20. 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

  1. Elastin-Derived Peptides Promote Abdominal Aortic Aneurysm Formation by Modulating M1/M2 Macrophage Polarization.

    PubMed

    Dale, Matthew A; Xiong, Wanfen; Carson, Jeffrey S; Suh, Melissa K; Karpisek, Andrew D; Meisinger, Trevor M; Casale, George P; Baxter, B Timothy

    2016-06-01

    Abdominal aortic aneurysm is a dynamic vascular disease characterized by inflammatory cell invasion and extracellular matrix degradation. Damage to elastin in the extracellular matrix results in release of elastin-derived peptides (EDPs), which are chemotactic for inflammatory cells such as monocytes. Their effect on macrophage polarization is less well known. Proinflammatory M1 macrophages initially are recruited to sites of injury, but, if their effects are prolonged, they can lead to chronic inflammation that prevents normal tissue repair. Conversely, anti-inflammatory M2 macrophages reduce inflammation and aid in wound healing. Thus, a proper M1/M2 ratio is vital for tissue homeostasis. Abdominal aortic aneurysm tissue reveals a high M1/M2 ratio in which proinflammatory cells and their associated markers dominate. In the current study, in vitro treatment of bone marrow-derived macrophages with EDPs induced M1 macrophage polarization. By using C57BL/6 mice, Ab-mediated neutralization of EDPs reduced aortic dilation, matrix metalloproteinase activity, and proinflammatory cytokine expression at early and late time points after aneurysm induction. Furthermore, direct manipulation of the M1/M2 balance altered aortic dilation. Injection of M2-polarized macrophages reduced aortic dilation after aneurysm induction. EDPs promoted a proinflammatory environment in aortic tissue by inducing M1 polarization, and neutralization of EDPs attenuated aortic dilation. The M1/M2 imbalance is vital to aneurysm formation. PMID:27183603

  2. Sympathetic stimulation facilitates thrombopoiesis by promoting megakaryocyte adhesion, migration, and proplatelet formation.

    PubMed

    Chen, Shilei; Du, Changhong; Shen, Mingqiang; Zhao, Gaomei; Xu, Yang; Yang, Ke; Wang, Xinmiao; Li, Fengju; Zeng, Dongfeng; Chen, Fang; Wang, Song; Chen, Mo; Wang, Cheng; He, Ting; Wang, Fengchao; Wang, Aiping; Cheng, Tianmin; Su, Yongping; Zhao, Jinghong; Wang, Junping

    2016-02-25

    The effect of sympathetic stimulation on thrombopoiesis is not well understood. Here, we demonstrate that both continual noise and exhaustive exercise elevate peripheral platelet levels in normal and splenectomized mice, but not in dopamine β-hydroxylase-deficient (Dbh(-/-)) mice that lack norepinephrine (NE) and epinephrine (EPI). Further investigation demonstrates that sympathetic stimulation via NE or EPI injection markedly promotes platelet recovery in mice with thrombocytopenia induced by 6.0 Gy of total-body irradiation and in mice that received bone marrow transplants after 10.0 Gy of lethal irradiation. Unfavorably, sympathetic stress-stimulated thrombopoiesis may also contribute to the pathogenesis of atherosclerosis by increasing both the amount and activity of platelets in apolipoprotein E-deficient (ApoE(-/-)) mice. In vitro studies reveal that both NE and EPI promote megakaryocyte adhesion, migration, and proplatelet formation (PPF) in addition to the expansion of CD34(+) cells, thereby facilitating platelet production. It is found that α2-adrenoceptor-mediated extracellular signal-regulated kinase 1/2 (ERK1/2) activation is involved in NE- and EPI-induced megakaryocyte adhesion and migration, and PPF is regulated by ERK1/2 activation-mediated RhoA GTPase signaling. Our data deeply characterize the role of sympathetic stimulation in the regulation of thrombopoiesis and reevaluate its physiopathological implications. PMID:26644453

  3. A systemic review of randomized controlled studies about prevention with pharmacologic agents of adhesion formation in the rat uterine horn model

    PubMed Central

    Ulug, Pasa

    2015-01-01

    Introduction Evaluation of treatment attempts in postoperative adhesion formation is pivotal for the prevention of several morbidities including infertility, pelvic pain, bowel obstruction, and subsequent intraoperative complications. The purpose of this systemic review was to assess the literature on the rat uterine horn model for adhesion formation and treatment modalities to prevent adhesion in the most frequently used experimental animal model. Material and methods We performed a systemic review of publications from January 1st 2000 to December 31st 2013 via a PubMed search. A high number of agents were evaluated for the prevention of postoperative adhesion formation in the rat uterine horn model. Results According to most of the studies, adjuvants such as antiinflamatuars, antiestrogens, antioxidants were effective to prevent adhesion formation. Conclusions Prevention of adhesion formation is pivotal and numerous types of agents were described in the literature were summarized in this review. PMID:25995741

  4. Molecular orbital studies in oxidation: Sulfate formation and metal-metal oxide adhesion

    NASA Technical Reports Server (NTRS)

    Anderson, A. B.

    1985-01-01

    The chemical mechanisms for sulfate formation from sodium chloride and sulfur trioxide, which is a product of jet fuel combustion was determined. Molten sodium sulfate leads to hot corrosion of the protective oxide layers on turbine blades. How yttrium dopants in nidkel-aluminum alloys used in turbine blades reduce the spalling rate of protective alumina films and enhance their adhesion was also determined. Two other fulfate mechanisms were deduced and structure of carbon monoxide on a clean chronium and clean platinum-titanium alloys surfaces was determined. All studies were by use of the atom superposition and electron delocalization molecular orbital (ASED-MO) theory. Seven studies were completed. Their titles and abstracts are given.

  5. 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

  6. Research of surface activating influence on formation of adhesion between gas-thermal coating and steel substrate

    NASA Astrophysics Data System (ADS)

    Kovalevskaya, Z.; Klimenov, V.; Zaitsev, K.

    2015-09-01

    Estimation of influence of physical and thermal activating on adhesion between steel substrates and thermal coatings has been performed. The substrates with surfaces obtained by and ultrasonic surface plastic deformation were used. To evaluate physical activating, preheating of the substrates to 600°C was performed. To evaluate the effect of thermal activating, the substrate surfaces after interfacial detachment were examined. Bonded areas on the substrate surfaces were measured by means of optical profilometry. The experiments have shown that surface physical activating is the main factor in formation of the adhesive bond between the coating and the substrate processed with the proposed methods.

  7. Targeted Gene Deletion Demonstrates that Cell Adhesion MoleculeICAM-4 is Critical for Erythroblastic Island Formation

    SciTech Connect

    Lee, Gloria; Lo, Annie; Short, Sarah A.; Mankelow, Tosti J.; Spring, Frances; Parsons, Stephen F.; Mohandas, Narla; Anstee, David J.; Chasis, Joel Anne

    2006-02-15

    Erythroid progenitors differentiate in erythroblastic islands, bone marrow niches composed of erythroblasts surrounding a central macrophage. Evidence suggests that within islands adhesive interactions regulate erythropoiesis and apoptosis. We are exploring whether erythroid intercellular adhesion molecule-4 (ICAM-4), animmunoglobulin superfamily member, participates in island formation. Earlier, we identified alpha V integrins as ICAM-4 counter receptors. Since macrophages express alpha V, ICAM-4 potentially mediates island attachments. To test this, we generated ICAM-4 knockout mice and developed quantitative, live cell techniques for harvesting intact islands and for reforming islands in vitro. We observed a 47 percent decrease in islands reconstituted from ICAM-4 null marrow compared to wild type. We also found a striking decrease in islands formed in vivo in knockout mice. Further, peptides that block ICAM-4 alpha V adhesion produced a 53-57 percent decrease in reconstituted islands, strongly suggesting that ICAM-4 binding to macrophage alpha V functions in island integrity. Importantly, we documented that alpha V integrin is expressed in macrophages isolated from erythro blastic islands. Collectively, these data provide convincing evidence that ICAM-4 is critical in erythroblastic island formation via ICAM-4/alpha V adhesion and also demonstrate that the novel experimental strategies we developed will be valuable in exploring molecular mechanisms of erythroblastic island formation and their functional role in regulating erythropoiesis.

  8. Focal adhesion kinase (FAK) phosphorylation is not required for genistein-induced FAK-beta-1-integrin complex formation.

    PubMed

    Liu, Y; Kyle, E; Lieberman, R; Crowell, J; Kellof, G; Bergan, R C

    2000-01-01

    It has previously been shown that changes in the activity of focal adhesion kinase (FAK), and its binding to beta-1-integrin, accompany genistein-induced adhesion of prostate cells. Consumption of genistein world wide is associated with a lower incidence of metastatic prostate cancer. Early human clinical trials of genistein are under way to evaluate genistein's potential causal role in this regard. Though an important cell adhesion-associated signaling molecule, FAK's role in regulating prostate cell adhesion was not clear. Elucidation of this process would provide important information relating to both biology and potential clinical endpoints. It was hypothesized that FAK activation and complex formation are temporally related in prostate cells, and can thus be separated. Significant activation of FAK was demonstrated when cells adhered to fibronectin, as compared to poly-L-lysine, thus demonstrating that beta-1-integrin plays a significant role in activating FAK. Neither FAK activation, nor FAK-integrin complex formation, required beta-1-integrin ligand. However, disruption of the cellular cytoskeleton by cytochalasin D prevented FAK activation, but did not block genistein-induced complex formation. In the face of a disrupted cytoskeleton, signaling through FAK could not be restored through either integrin cross linking, or re-establishment of tensile forces via attachment to solid matrix. These studies demonstrate that FAK-beta-1-integrin complex formation does not require FAK activation, suggesting that it is an early event in prostate cell adhesion. An intact cytoskeleton is necessary for FAK activation. The functional importance of beta-1-integrin in prostate cells is demonstrated. Current findings support plans to test genistein in prostate cancer. PMID:11315093

  9. Caveolin 1 is critical for abdominal aortic aneurysm formation induced by angiotensin II and inhibition of lysyl oxidase.

    PubMed

    Takayanagi, Takehiko; Crawford, Kevin J; Kobayashi, Tomonori; Obama, Takashi; Tsuji, Toshiyuki; Elliott, Katherine J; Hashimoto, Tomoki; Rizzo, Victor; Eguchi, Satoru

    2014-06-01

    Although AngII (angiotensin II) and its receptor AT1R (AngII type 1 receptor) have been implicated in AAA (abdominal aortic aneurysm) formation, the proximal signalling events primarily responsible for AAA formation remain uncertain. Caveolae are cholesterol-rich membrane microdomains that serve as a signalling platform to facilitate the temporal and spatial localization of signal transduction events, including those stimulated by AngII. Cav1 (caveolin 1)-enriched caveolae in vascular smooth muscle cells mediate ADAM17 (a disintegrin and metalloproteinase 17)-dependent EGFR (epidermal growth factor receptor) transactivation, which is linked to vascular remodelling induced by AngII. In the present study, we have tested our hypothesis that Cav1 plays a critical role for the development of AAA at least in part via its specific alteration of AngII signalling within caveolae. Cav1-/- mice and the control wild-type mice were co-infused with AngII and β-aminopropionitrile to induce AAA. We found that Cav1-/- mice with the co-infusion did not develop AAA compared with control mice in spite of hypertension. We found an increased expression of ADAM17 and enhanced phosphorylation of EGFR in AAA. These events were markedly attenuated in Cav1-/- aortas with the co-infusion. Furthermore, aortas from Cav1-/- mice with the co-infusion showed less endoplasmic reticulum stress, oxidative stress and inflammatory responses compared with aortas from control mice. Cav1 silencing in cultured vascular smooth muscle cells prevented AngII-induced ADAM17 induction and activation. In conclusion, Cav1 appears to play a critical role in the formation of AAA and associated endoplasmic reticulum/oxidative stress, presumably through the regulation of caveolae compartmentalized signals induced by AngII. PMID:24329494

  10. Terpenoids of plant origin inhibit morphogenesis, adhesion, and biofilm formation by Candida albicans.

    PubMed

    Raut, Jayant S; Shinde, Ravikumar B; Chauhan, Nitin M; Karuppayil, S Mohan

    2013-01-01

    Biofilm-related infections caused by Candida albicans and associated drug resistant micro-organisms are serious problems for immunocompromised populations. Molecules which can prevent or remove biofilms are needed. Twenty-eight terpenoids of plant origin were analysed for their activity against growth, virulence attributes, and biofilms of C. albicans. Eighteen molecules exhibited minimum inhibitory concentrations of <2 mg ml(-1) for planktonic growth. Selected molecules inhibited yeast to hyphal dimorphism at low concentrations (0.031-0.5 mg ml(-1)), while adhesion to a solid surface was prevented at 0.5-2 mg ml(-1). Treatment with 14 terpenoids resulted in significant (p < 0.05) inhibition of biofilm formation, and of these, linalool, nerol, isopulegol, menthol, carvone, α-thujone, and farnesol exhibited biofilm-specific activity. Eight terpenoids were identified as inhibitors of mature biofilms. This study demonstrated the antibiofilm potential of terpenoids, which need to be further explored as therapeutic strategy against biofilm associated infections of C. albicans. PMID:23216018

  11. 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

  12. Abdominal mass

    MedlinePlus

    Several conditions can cause an abdominal mass: Abdominal aortic aneurysm can cause a pulsating mass around the navel. ... This could be a sign of a ruptured aortic aneurysm, which is an emergency condition. Contact your health ...

  13. Abdominal mass

    MedlinePlus

    ... Several conditions can cause an abdominal mass: Abdominal aortic aneurysm can cause a pulsating mass around the navel. ... This could be a sign of a ruptured aortic aneurysm, which is an emergency condition. Contact your health ...

  14. Peritoneal adhesions after laparoscopic gastrointestinal surgery

    PubMed Central

    Mais, Valerio

    2014-01-01

    60%. A recent small, randomized clinical trial suggested that the combination of broad peritoneal cavity protection with local application of a barrier could be almost 100% effective in preventing post-operative adhesion formation. Future studies should confirm the efficacy of this global strategy in preventing adhesion formation after laparoscopy by focusing on clinical end points, such as reduced incidences of bowel obstruction and abdominal pain and increased fertility. PMID:24803803

  15. 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

  16. Role of the von Hippel-Lindau tumor suppressor gene in the formation of beta1-integrin fibrillar adhesions.

    PubMed

    Esteban-Barragán, Miguel A; Avila, Pilar; Alvarez-Tejado, Miguel; Gutiérrez, M Dolores; García-Pardo, Angeles; Sánchez-Madrid, Francisco; Landázuri, Manuel O

    2002-05-15

    The von Hippel-Lindau tumor suppressor gene (VHL) is absent or inactivated in the VHLcancer syndrome and in most sporadic renal cancers. VHL is requiredfor the assembly of a proper extracellular fibronectin matrix, although the exact mechanism remains unknown. In this report, we demonstrate that 786-O renal cancer cells are unable to organize an adequate matrix even in the presence of an excess of exogenous fibronectin. Because the formation of integrin fibrillar adhesions plays a pivotal role in the organization of extracellular fibronectin, we next examined the expression and subcellular distribution of integrins in VHL- cells and their wild-type VHL stably transfected counterparts. The levels of beta1 and alphav integrins were increased in VHL- cells when compared with VHL+ transfectants. Early after plating, both VHL+ and VHL- cells were capable of assembling classic "patch-like" alphav focal contacts. As the culture advanced and cells became confluent, alphav integrins partly relocated to the intercellular junctions in VHL+ transfectants, which then developed large beta1 fibrillar-type adhesions and anchored firmly to the substrate. In contrast, confluent VHL- cells were unable to assemble beta1 fibrillar adhesions, and alphav focal contacts remained unchanged at all stages of the culture. Exogenous activation of beta1 integrins with either divalent cations or activating antibodies partly restored the capability of VHL- cells to assemble beta1 fibrillar adhesions and fibronectin fibers. Finally, pulse-chase studies of metabolically labeled 786-O cells revealed that the maturation of the common beta1-integrin chain was delayed in VHL- cells when compared with VHL+ cells. Our results show that VHL is an important regulator of integrins and is essential for the formation of beta1 fibrillar adhesions. These findings help to explain the abnormal extracellular matrix organization and increased motility of VHL- renal cancer cells. PMID:12019174

  17. Quantitative analysis of adhesion and biofilm formation on hydrophilic and hydrophobic surfaces of clinical isolates of Staphylococcus epidermidis.

    PubMed

    Cerca, Nuno; Pier, Gerald B; Vilanova, Manuel; Oliveira, Rosário; Azeredo, Joana

    2005-05-01

    Staphylococcus epidermidis is now well established as a major nosocomial pathogen associated with infections of indwelling medical devices. The major virulence factor of these organisms is their ability to adhere to devices and form biofilms. However, it has not been established that adherence and biofilm formation are closely linked phenotypes for clinical isolates. In this study, the initial adhesion to different materials (acrylic and glass) of 9 clinical isolates of S. epidermidis, along with biofilm-positive and biofilm-negative control strains, was assayed using physico-chemical interactions to analyze the basis for bacterial adherence to the substratum. X-ray photo electron spectroscopy (XPS) analysis of the cell surface elemental composition was also performed in an attempt to find a relationship between chemical composition and adhesion capabilities. Biofilm formation on the two surfaces was evaluated by dry weight measurements. Human erythrocytes were used to evaluate the ability of S. epidermidis strains to cause hemagglutination, an indicator of the production of a poly-N-acetyl glucosamine cell surface polysaccharide also involved in biofilm formation. The clinical isolates exhibited different cell wall physico-chemical properties, resulting in differing abilities to adhere to surfaces. Adhesion to hydrophobic substrata for all strains occurred to a greater extent than that to hydrophilic surfaces. Bacterial cell hydrophobicity seemed to have little or no influence on adhesion. X-ray photoelectron spectroscopy analysis showed a high ratio of oxygen/carbon for all strains, which is a common characteristic of S. epidermidis species. No relevant relationship was found between XPS data and adhesion values. All strains forming biofilms were able to agglutinate erythrocytes. However, no direct relationship was found between the amount of biofilm formed and the initial adhesion extent. These results indicate that high levels of initial adherence do not

  18. Effect of hyaluronic acid on postoperative intraperitoneal adhesion formation and reformation in the rat model

    SciTech Connect

    Urman, B.; Gomel, V. )

    1991-09-01

    The local application of 0.25% or 0.4% HA before the induction of a measured laser injury on the rat uterine horn was associated with a significant reduction (P less than 0.05) in postoperative IP adhesions when compared with the group of animals pretreated with the diluent vehicle PBS or received no pretreatment. However, 0.4% HA, when applied in a similar manner, was ineffective in reducing reformation of adhesions after microsurgical adhesiolysis.

  19. Cross-linked hyaluronate hydrogel prevents adhesion formation and reformation in mouse uterine horn model.

    PubMed

    Sawada, T; Tsukada, K; Hasegawa, K; Ohashi, Y; Udagawa, Y; Gomel, V

    2001-02-01

    The aim of this study was to evaluate the efficacy of cross-linked hyaluronate hydrogel (HA gel) as an adjuvant for postoperative adhesion prevention, in a mouse uterine horn model. In experiment 1 uterine horns were abrased with iodine. HA gel was applied to the injured surface before closure in the treatment group. In experiment 2, after injuring the uterine horns, three stitches were placed at equal distances around the uterine horns to appose the injured medial surfaces of the two horns during healing. HA gel was inserted between the uterine horns in the treatment group. In experiment 3 prevention of adhesion reformation was assessed. After lysis of adhesions that were induced as in experiment 2, HA gel was introduced between the serosal surfaces of apposing uterine horns. Untreated animals served as controls in each experiment. Statistical analysis was carried out using Student's t-test. The adhesion score was significantly lower in the HA gel group on the 14th day compared with controls in all the experiments: in experiment 1, 0.3 +/- 0.4 versus 1.7 +/- 1.2; in experiment 2, 0.9 +/- 1.0 versus 2.6 +/- 0.5; and in experiment 3, 1.5 +/- 0.9 versus 2.2 +/- 0.6 respectively. Cross-linked HA gel significantly reduced de-novo adhesions (P< 0.03) and adhesion reformation (P < 0.03). PMID:11157833

  20. Dentin bonding performance using Weibull statistics and evaluation of acid-base resistant zone formation of recently introduced adhesives.

    PubMed

    Guan, Rui; Takagaki, Tomohiro; Matsui, Naoko; Sato, Takaaki; Burrow, Michael F; Palamara, Joseph; Nikaido, Toru; Tagami, Junji

    2016-07-30

    Dentin bonding durability of recently introduced dental adhesives: Clearfil SE Bond 2 (SE2), Optibond XTR (XTR), and Scotchbond Universal (SBU) was investigated using Weibull analysis as well as analysis of the micromorphological features of the acid-base resistant zone (ABRZ) created for the adhesives. The bonding procedures of SBU were divided into three subgroups: self-etch (SBS), phosphoric acid (PA) etching on moist (SBM) or dry dentin (SBD). All groups were thermocycled for 0, 5,000 and 10,000 cycles followed by microtensile bond strength testing. Acid-base challenge was undertaken before SEM and TEM observations of the adhesive interface. The etch-and-rinse method with SBU (SBM and SBD) created inferior interfaces on the dentin surface which resulted in reduced bond durability. ABRZ formation was detected with the self-etch adhesive systems; SE2, XTR and SBS. In the PA etching protocols of SBM and SBD, a thick hybrid layer but no ABRZ was detected, which might affect dentin bond durability. PMID:27335136

  1. Increased expression of leukotriene C4 synthase and predominant formation of cysteinyl-leukotrienes in human abdominal aortic aneurysm

    PubMed Central

    Di Gennaro, Antonio; Wågsäter, Dick; Mäyränpää, Mikko I.; Gabrielsen, Anders; Swedenborg, Jesper; Hamsten, Anders; Samuelsson, Bengt; Eriksson, Per; Haeggström, Jesper Z.

    2010-01-01

    Leukotrienes (LTs) are arachidonic acid-derived lipid mediators involved in the pathogenesis and progression of diverse inflammatory disorders. The cysteinyl-leukotrienes LTC4, LTD4, and LTE4 are important mediators of asthma, and LTB4 has recently been implicated in atherosclerosis. Here we report that mRNA levels for the three key enzymes/proteins in the biosynthesis of cysteinyl-leukotrienes, 5-lipoxygenase (5-LO), 5-LO-activating protein (FLAP), and LTC4 synthase (LTC4S), are significantly increased in the wall of human abdominal aortic aneurysms (AAAs). In contrast, mRNA levels of LTA4 hydrolase, the enzyme responsible for the biosynthesis of LTB4, are not increased. Immunohistochemical staining of AAA wall revealed focal expression of 5-LO, FLAP, and LTC4S proteins in the media and adventitia, localized in areas rich in inflammatory cells, including macrophages, neutrophils, and mast cells. Human AAA wall tissue converts arachidonic acid and the unstable epoxide LTA4 into significant amounts of cysteinyl-leukotrienes and to a lesser extent LTB4. Furthermore, challenge of AAA wall tissue with exogenous LTD4 increases the release of matrix metalloproteinase (MMP) 2 and 9, and selective inhibition of the CysLT1 receptor by montelukast blocks this effect. The increased expression of LTC4S, together with the predominant formation of cysteinyl-leukotrienes and effects on MMPs production, suggests a mechanism by which LTs may promote matrix degradation in the AAA wall and identify the components of the cysteinyl-leukotriene pathway as potential targets for prevention and treatment of AAA. PMID:21078989

  2. 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.

  3. Normalizing the bone marrow microenvironment with p38 inhibitor reduces multiple myeloma cell proliferation and adhesion and suppresses osteoclast formation

    SciTech Connect

    Nguyen, Aaron N.; Stebbins, Elizabeth G.; Henson, Margaret; O'Young, Gilbert; Choi, Sun J.; Quon, Diana; Damm, Debby; Reddy, Mamatha; Ma, Jing Y.; Haghnazari, Edwin; Kapoun, Ann M.; Medicherla, Satyanarayana; Protter, Andy; Schreiner, George F.; Kurihara, Noriyoshi; Anderson, Judy; Roodman, G. David; Navas, Tony A.; Higgins, Linda S. . E-mail: lhiggin3@scius.jnj.com

    2006-06-10

    The multiple myeloma (MM) bone marrow (BM) microenvironment plays a critical role in supporting tumor growth and survival as well as in promoting formation of osteolytic lesions. Recent results suggest that the p38 mitogen-activated protein kinase (MAPK) is an important factor in maintaining this activated environment. In this report, we demonstrate that the p38{alpha} MAPK inhibitor, SCIO-469, suppresses secretion of the tumor-supportive factors IL-6 and VEGF from BM stromal cells (BMSCs) as well as cocultures of BMSCs with MM cells, resulting in reduction in MM cell proliferation. Additionally, we show that SCIO-469 prevents TNF{alpha}-induced adhesion of MM cells to BMSCs through an ICAM-1- and VCAM-1-independent mechanism. Microarray analysis revealed a novel set of TNF{alpha}-induced chemokines in BMSCs that is strongly inhibited by SCIO-469. Furthermore, reintroduction of chemokines CXCL10 and CCL8 to BMSCs overcomes the inhibitory effect of SCIO-469 on TNF{alpha}-induced MM adhesion. Lastly, we show that SCIO-469 inhibits secretion and expression of the osteoclast-activating factors IL-11, RANKL, and MIP-1{alpha} as well as prevents human osteoclast formation in vitro. Collectively, these results suggest that SCIO-469 treatment can suppress factors in the bone marrow microenvironment to inhibit MM cell proliferation and adhesion and also to alleviate osteolytic activation in MM.

  4. Investigation Of Adhesion Formation In New Stainless Steel Trim Spring Operated Pressure Relief Valves

    SciTech Connect

    Gross, Robert E.; Bukowski, Julia V.; Goble, William M.

    2013-04-16

    Examination of proof test data for new (not previously installed) stainless steel (SS) trim spring operated pressure relief valves (SOPRV) reveals that adhesions form between the seat and disc in about 46% of all such SOPRV. The forces needed to overcome these adhesions can be sufficiently large to cause the SOPRV to fail its proof test (FPT) prior to installation. Furthermore, a significant percentage of SOPRV which are found to FPT are also found to ''fail to open'' (FTO) meaning they would not relief excess pressure in the event of an overpressure event. The cases where adhesions result in FTO or FPT appear to be confined to SOPRV with diameters < 1 in and set pressures < 150 psig and the FTO are estimated to occur in 0.31% to 2.00% of this subpopulation of SS trim SOPRV. The reliability and safety implications of these finding for end-users who do not perform pre-installation testing of SOPRV are discussed.

  5. Investigation into the Formation and Adhesion of Cyclopentane Hydrates on Mechanically Robust Vapor-Deposited Polymeric Coatings.

    PubMed

    Sojoudi, Hossein; Walsh, Matthew R; Gleason, Karen K; McKinley, Gareth H

    2015-06-01

    Blockage of pipelines by formation and accumulation of clathrate hydrates of natural gases (also called gas hydrates) can compromise project safety and economics in oil and gas operations, particularly at high pressures and low temperatures such as those found in subsea or arctic environments. Cyclopentane (CyC5) hydrate has attracted interest as a model system for studying natural gas hydrates, because CyC5, like typical natural gas hydrate formers, is almost fully immiscible in water; and thus CyC5 hydrate formation is governed not only by thermodynamic phase considerations but also kinetic factors such as the hydrocarbon/water interfacial area, as well as mass and heat transfer constraints, as for natural gas hydrates. We present a macroscale investigation of the formation and adhesion strength of CyC5 hydrate deposits on bilayer polymer coatings with a range of wettabilities. The polymeric bilayer coatings are developed using initiated chemical vapor deposition (iCVD) of a mechanically robust and densely cross-linked polymeric base layer (polydivinylbenzene or pDVB) that is capped with a covalently attached thin hydrate-phobic fluorine-rich top layer (poly(perfluorodecyl acrylate) or pPFDA). The CyC5 hydrates are formed from CyC5-in-water emulsions, and differential scanning calorimetry (DSC) is used to confirm the thermal dissociation properties of the solid hydrate deposits. We also investigate the adhesion of the CyC5 hydrate deposits on bare and bilayer polymer-coated silicon and steel substrates. Goniometric measurements with drops of CyC5-in-water emulsions on the coated steel substrates exhibit advancing contact angles of 148.3 ± 4.5° and receding contact angles of 142.5 ± 9.8°, indicating the strongly emulsion-repelling nature of the iCVD coatings. The adhesion strength of the CyC5 hydrate deposits is reduced from 220 ± 45 kPa on rough steel substrates to 20 ± 17 kPa on the polymer-coated steel substrates. The measured strength of CyC5 hydrate

  6. Abdominal closure reinforcement by using polypropylene mesh functionalized with poly-ε-caprolactone nanofibers and growth factors for prevention of incisional hernia formation

    PubMed Central

    Plencner, Martin; East, Barbora; Tonar, Zbyněk; Otáhal, Martin; Prosecká, Eva; Rampichová, Michala; Krejčí, Tomáš; Litvinec, Andrej; Buzgo, Matej; Míčková, Andrea; Nečas, Alois; Hoch, Jiří; Amler, Evžen

    2014-01-01

    Incisional hernia affects up to 20% of patients after abdominal surgery. Unlike other types of hernia, its prognosis is poor, and patients suffer from recurrence within 10 years of the operation. Currently used hernia-repair meshes do not guarantee success, but only extend the recurrence-free period by about 5 years. Most of them are nonresorbable, and these implants can lead to many complications that are in some cases life-threatening. Electrospun nanofibers of various polymers have been used as tissue scaffolds and have been explored extensively in the last decade, due to their low cost and good biocompatibility. Their architecture mimics the natural extracellular matrix. We tested a biodegradable polyester poly-ε-caprolactone in the form of nanofibers as a scaffold for fascia healing in an abdominal closure-reinforcement model for prevention of incisional hernia formation. Both in vitro tests and an experiment on a rabbit model showed promising results. PMID:25031534

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

    SciTech Connect

    Suzuki, Yuka; Tada-Oikawa, Saeko; Ichihara, Gaku; Yabata, Masayuki; Izuoka, Kiyora; Suzuki, Masako; Sakai, Kiyoshi; Ichihara, Sahoko

    2014-07-01

    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 monocyte 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.

  8. The role of cell adhesion molecules in visual circuit formation: from neurite outgrowth to maps and synaptic specificity.

    PubMed

    Missaire, Mégane; Hindges, Robert

    2015-06-01

    The formation of visual circuitry is a multistep process that involves cell-cell interactions based on a range of molecular mechanisms. The correct implementation of individual events, including axon outgrowth and guidance, the formation of the topographic map, or the synaptic targeting of specific cellular subtypes, are prerequisites for a fully functional visual system that is able to appropriately process the information captured by the eyes. Cell adhesion molecules (CAMs) with their adhesive properties and their high functional diversity have been identified as key actors in several of these fundamental processes. Because of their growth-promoting properties, CAMs play an important role in neuritogenesis. Furthermore, they are necessary to control additional neurite development, regulating dendritic spacing and axon pathfinding. Finally, trans-synaptic interactions of CAMs ensure cell type-specific connectivity as a basis for the establishment of circuits processing distinct visual features. Recent discoveries implicating CAMs in novel mechanisms have led to a better general understanding of neural circuit formation, but also revealed an increasing complexity of their function. This review aims at describing the different levels of action for CAMs to shape neural connectivity, with a special focus on the visual system. PMID:25649254

  9. The role of cell adhesion molecules in visual circuit formation: From neurite outgrowth to maps and synaptic specificity

    PubMed Central

    Missaire, Mégane

    2015-01-01

    ABSTRACT The formation of visual circuitry is a multistep process that involves cell–cell interactions based on a range of molecular mechanisms. The correct implementation of individual events, including axon outgrowth and guidance, the formation of the topographic map, or the synaptic targeting of specific cellular subtypes, are prerequisites for a fully functional visual system that is able to appropriately process the information captured by the eyes. Cell adhesion molecules (CAMs) with their adhesive properties and their high functional diversity have been identified as key actors in several of these fundamental processes. Because of their growth‐promoting properties, CAMs play an important role in neuritogenesis. Furthermore, they are necessary to control additional neurite development, regulating dendritic spacing and axon pathfinding. Finally, trans‐synaptic interactions of CAMs ensure cell type‐specific connectivity as a basis for the establishment of circuits processing distinct visual features. Recent discoveries implicating CAMs in novel mechanisms have led to a better general understanding of neural circuit formation, but also revealed an increasing complexity of their function. This review aims at describing the different levels of action for CAMs to shape neural connectivity, with a special focus on the visual system. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 75: 569–583, 2015 PMID:25649254

  10. Polyurethane adhesive ingestion.

    PubMed

    Fitzgerald, Kevin T; Bronstein, Alvin C

    2013-02-01

    Polyurethane adhesives are found in a large number of household products in the United States and are used for a variety of purposes. Several brands of these expanding wood glues (those containing diphenylmethane diisocyanate [MDI]) have the potential to form gastrointestinal (GI) foreign bodies if ingested. The ingested adhesive forms an expanding ball of glue in the esophagus and gastric lumen. This expansion is caused by a polymerization reaction using the heat, water, and gastric acids of the stomach. A firm mass is created that can be 4-8 times its original volume. As little as 2 oz of glue have been reported to develop gastric foreign bodies. The obstructive mass is reported to form within minutes of ingestion of the adhesive. The foreign body can lead to esophageal impaction and obstruction, airway obstruction, gastric outflow obstruction, mucosal hemorrhage, ulceration, laceration, perforation of the esophageal and gastric linings, and death. Clinical signs following ingestion include anorexia, lethargy, vomiting, tachypnea, and abdominal distention and pain, and typically develop within 12 hours. Clinical signs may depend upon the size of the mass. If left untreated, perforation and rupture of the esophagus or stomach can occur. The glue mass does not stick to the GI mucosa and is not always detectable on abdominal palpation. Radiographs are recommended to confirm the presence of the "glue-ball" foreign body, and radiographic evidence of the obstruction may be seen as early as 4-6 hours following ingestion. Emesis is contraindicated owing to the risk of aspiration of the glue into the respiratory tree or the subsequent lodging of the expanding glue mass in the esophagus. Likewise, efforts to dilute the glue and prevent the formation of the foreign body through administration of liquids, activated charcoal, or bulk-forming products to push the foreign body through the GI tract have proven ineffective. Even endoscopy performed to remove the foreign body has

  11. Recoupling of eNOS with Folic Acid Prevents Abdominal Aortic Aneurysm Formation in Angiotensin II-Infused Apolipoprotein E Null Mice

    PubMed Central

    Siu, Kin Lung; Miao, Xiao Niu; Cai, Hua

    2014-01-01

    We have previously shown that eNOS uncoupling mediates abdominal aortic aneurysm (AAA) formation in hph-1 mice. In the present study we examined whether recoupling of eNOS prevents AAA formation in a well-established model of Angiotensin II-infused apolipoprotein E (apoE) null mice by targeting some common pathologies of AAA. Infusion of Ang II resulted in a 92% incidence rate of AAA in the apoE null animals. In a separate group, animals were treated orally with folic acid (FA), which is known to recouple eNOS through augmentation of dihydrofolate reductase (DHFR) function. This resulted in a reduction of AAA rate to 19.5%. Imaging with ultrasound showed that FA markedly inhibited expansion of abdominal aorta. FA also abolished elastin breakdown and macrophage infiltration in the AAA animals. The eNOS uncoupling activity, assessed by L-NAME-sensitive superoxide production, was minimal at baseline but greatly exaggerated with Ang II infusion, which was completely attenuated by FA. This was accompanied by markedly improved tetrahydrobiopterin and nitric oxide bioavailability. Furthermore, the expression and activity of DHFR was decreased in Ang II-infused apoE null mice specifically in the endothelial cells, while FA administration resulted in its recovery. Taken together, these data further establish a significant role of uncoupled eNOS in mediating AAA formation, and a universal efficacy of FA in preventing AAA formation via restoration of DHFR to restore eNOS function. PMID:24558445

  12. Adhesion to and biofilm formation on IB3-1 bronchial cells by Stenotrophomonas maltophilia isolates from cystic fibrosis patients

    PubMed Central

    2010-01-01

    Background Stenotrophomonas maltophilia has recently gained considerable attention as an important emerging pathogen in cystic fibrosis (CF) patients. However, the role of this microorganism in the pathophysiology of CF lung disease remains largely unexplored. In the present study for the first time we assessed the ability of S. maltophilia CF isolates to adhere to and form biofilm in experimental infection experiments using the CF-derived bronchial epithelial IB3-1cell line. The role of flagella on the adhesiveness of S. maltophilia to IB3-1 cell monolayers was also assessed by using fliI mutant derivative strains. Results All S. maltophilia CF isolates tested in the present study were able, although at different levels, to adhere to and form biofilm on IB3-1 cell monolayers. Scanning electron and confocal microscopy revealed S. maltophilia structures typical of biofilm formation on bronchial IB3-1 cells. The loss of flagella significantly (P < 0.001) decreased bacterial adhesiveness, if compared to that of their parental flagellated strains. S. maltophilia CF isolates were also able to invade IB3-1 cells, albeit at a very low level (internalization rate ranged from 0.01 to 4.94%). Pre-exposure of IB3-1 cells to P. aeruginosa PAO1 significantly increased S. maltophilia adhesiveness. Further, the presence of S. maltophilia negatively influenced P. aeruginosa PAO1 adhesiveness. Conclusions The main contribution of the present study is the finding that S. maltophilia is able to form biofilm on and invade CF-derived IB3-1 bronchial epithelial cells, thus posing a rationale for the persistence and the systemic spread of this opportunistic pathogen in CF patients. Experiments using in vivo models which more closely mimic CF pulmonary tissues will certainly be needed to validate the relevance of our results. PMID:20374629

  13. Inhibition of focal adhesion kinase prevents experimental lung fibrosis and myofibroblast formation

    PubMed Central

    Lagares, David; Busnadiego, Oscar; García-Fernández, Rosa Ana; Kapoor, Mohit; Liu, Shangxi; Carter, David E.; Abraham, David; Shi-Wen, Xu; Carreira, Patricia; Fontaine T, Benjamin A; Shea, Barry S; Tager, Andrew M; Leask, Andrew; Lamas, Santiago; Rodríguez-Pascual, Fernando

    2011-01-01

    Objective Enhanced adhesive signaling including activation of the focal adhesion kinase (FAK) is a hallmark of fibroblasts from lung fibrosis patients, and FAK has been therefore hypothesized to be a key mediator of this disease. This study was undertaken to characterize the contribution of FAK to the development of pulmonary fibrosis both in vivo and in vitro. Methods FAK expression and activity were analyzed in lung tissue samples from lung fibrosis patients by immunohistochemistry. Mice orally treated with the FAK inhibitor, PF-562,271, or with siRNA-mediated silencing of FAK, were exposed to intratracheally instilled bleomycin to induce lung fibrosis, and the lungs were harvested for histological and biochemical analysis. Using endothelin-1 (ET-1) as stimulus, cell adhesion and contraction, as well as profibrotic gene expression were studied in fibroblasts isolated from wild type and FAK-deficient mouse embryos. ET-1-mediated FAK activation and gene expression were studied in primary mouse lung fibroblasts, as well as in wild type and integrin β1-deficient fibroblasts. Results Increased FAK expression and activity are upregulated in fibroblast foci and remodeled vessels in lung fibrosis patients. Pharmacological or siRNA-mediated targeting of FAK resulted in marked abrogation of bleomycin-induced lung fibrosis. Loss of FAK impaired the acquisition of a profibrotic phenotype in response to ET-1. Profibrotic gene expression leading to myofibroblast differentiation required cell adhesion, and was driven by Jun N-terminal kinase activation through integrin β1/FAK signaling. Conclusion These results implicate FAK as a central mediator of fibrogenesis, and highlight this kinase as a potential therapeutic target in fibrotic diseases. PMID:22492165

  14. Fibrinogen-independent platelet adhesion and thrombus formation on subendothelium mediated by glycoprotein IIb-IIIa complex at high shear rate.

    PubMed Central

    Weiss, H J; Hawiger, J; Ruggeri, Z M; Turitto, V T; Thiagarajan, P; Hoffmann, T

    1989-01-01

    Platelet adhesion and thrombus formation on subendothelium, studied at a shear rate of 2,600 s-1, were inhibited by two synthetic peptides known to interact with GPIIb-IIIa. One peptide (HHLGGAKQAGDV) corresponds to the carboxyl terminal segment of the fibrinogen gamma-chain (gamma 400-411) and the other (RGDS) contains the amino acid sequence Arg-Gly-Asp (RGD) common to fibronectin, von Willebrand factor, vitronectin and the alpha-chain of fibrinogen. Neither platelet adhesion nor thrombus formation were decreased in a patient with severe congenital fibrinogen deficiency and this was equally true when his blood was further depleted of the small amounts of fibrinogen present utilizing an anti-fibrinogen antibody. In normal subjects, adhesion and thrombus formation were inhibited by the Fab' fragments of a monoclonal anti-GPIIb-IIIa antibody (LJ-CP8), which interferes with the interaction of platelets with all four adhesive proteins in both the fluid and solid phase. However, another anti-GPIIb-IIIa antibody (LJ-P5) that had minimal effects on the interaction of platelets with fibrinogen, but inhibited to varying degrees platelet interaction with other adhesive proteins, was equally effective. The findings demonstrate that, at a shear rate of 2,600 s-1, adhesive proteins other than fibrinogen are involved in GPIIb-IIIa-mediated platelet adhesion and thrombus formation on subendothelium. In addition, since LJ-P5 inhibited the binding of soluble von Willebrand factor and vitronectin, these adhesive proteins may be involved in platelet thrombus formation. In contrast to the results obtained at a shear rate of 2,600 s-1, fibrinogen could play a role in mediating platelet-platelet interactions with weak agonists or lower shear rates. PMID:2910912

  15. Biofilm Formation and the Presence of the Intercellular Adhesion Locus ica among Staphylococci from Food and Food Processing Environments

    PubMed Central

    Møretrø, Trond; Hermansen, Lene; Holck, Askild L.; Sidhu, Maan S.; Rudi, Knut; Langsrud, Solveig

    2003-01-01

    In clinical staphylococci, the presence of the ica genes and biofilm formation are considered important for virulence. Biofilm formation may also be of importance for survival and virulence in food-related staphylococci. In the present work, staphylococci from the food industry were found to differ greatly in their abilities to form biofilms on polystyrene. A total of 7 and 21 of 144 food-related strains were found to be strong and weak biofilm formers, respectively. Glucose and sodium chloride stimulated biofilm formation. The biofilm-forming strains belonged to nine different coagulase-negative species of Staphylococcus. The icaA gene of the intercellular adhesion locus was detected by Southern blotting and hybridization in 38 of 67 food-related strains tested. The presence of icaA was positively correlated with strong biofilm formation. The icaA gene was partly sequenced for 22 food-related strains from nine different species of Staphylococcus, and their icaA genes were found to have DNA similarities to previously sequenced icaA genes of 69 to 100%. Northern blot analysis indicated that the expression of the ica genes was higher in strong biofilm formers than that seen with strains not forming biofilms. Biofilm formation on polystyrene was positively correlated with biofilm formation on stainless steel and with resistance to quaternary ammonium compounds, a group of disinfectants. PMID:12957956

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

    PubMed

    Suzuki, Yuka; Tada-Oikawa, Saeko; Ichihara, Gaku; Yabata, Masayuki; Izuoka, Kiyora; Suzuki, Masako; Sakai, Kiyoshi; Ichihara, Sahoko

    2014-07-01

    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 TiO2 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 monocyte 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 TiO2 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. PMID:24746987

  17. 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. PMID:27105066

  18. Splat Formation and Adhesion Mechanisms of Cold Gas-Sprayed Al Coatings on Al2O3 Substrates

    NASA Astrophysics Data System (ADS)

    Drehmann, R.; Grund, T.; Lampke, T.; Wielage, B.; Manygoats, K.; Schucknecht, T.; Rafaja, D.

    2014-01-01

    The metallization of ceramics by means of cold gas spraying (CGS) has been in the focus of numerous publications in the recent past. However, the bonding mechanism of metallic coatings on non-ductile substrates is still not fully understood. Former investigations of titanium coatings deposited on corundum revealed that a combination of recrystallization induced by adiabatic shear processes and hetero-epitaxial growth might be responsible for the high adhesion strengths of coatings applied on smooth ceramic surfaces. In the present work, the interface formation between CGS aluminum and alumina substrates is examined for different particle sizes and substrate temperatures. Furthermore, the influence of subsequent heat treatment on tensile strength and hardness is investigated. The splat formation of single particles is examined by means of scanning electron microscopy, while a high resolution transmission electron microscope is used to study the Al/Al2O3 interface. First results suggest that mechanical interlocking is the primary adhesion mechanism on polycrystalline substrates having the roughness in sub-micrometer range, while the heteroepitaxy between Al and Al2O3 can be considered as the main bonding mechanism for single-crystalline sapphire (α-Al2O3) substrates with the surface roughness in nanometer range. The heteroepitaxial growth is facilitated by deformation-induced recrystallisation of CGS aluminum.

  19. Formation of Osteogenic Colonies on Well-Defined Adhesion Peptides by Freshly-Isolated Human Marrow Cells

    PubMed Central

    Au, Ada; Boehm, Cynthia A.; Mayes, Anne M.; Muschler, George F.; Griffith, Linda G.

    2007-01-01

    Bone graft performance can be enhanced by addition of connective tissue progenitors (CTPs) from fresh bone marrow in a manner that concentrates the CTP cell population within the graft. Here, we used small peptide adhesion ligands presented against an otherwise adhesion-resistant synthetic polymer background in order to illuminate the molecular basis for the attachment and colony formation by osteogenic CTPs from fresh human marrow, and contrast the behavior of fresh marrow to many commonly-used osteogenic cell sources. The linear GRGDSPY ligand was as effective as tissue culture polystyrene in fostering attachment of culture-expanded porcine CTPs. Although this GRGDSPY peptide was more effective than control peptides in fostering alkaline phosphatase-positive (AP) colony formation from primary human marrow in 5 of the 7 patients tested, GRGDSPY was as effective as the control glass substrate in only one patient of 7. Thus, the peptide appears capable of enabling osteoblastic development from only a subpopulation of CTPs in marrow. The bone sialoprotein-derived peptide FHRRIKA was ineffective in fostering attachment of primary culture-expanded pig CTPs, although it was as effective as GRGDSPY in fostering AP-positive colonies from fresh human marrow. This study provides insights into integrin-mediated behaviors of CTPs and highlights differences between freshly-isolated marrow and culture-expanded cells. PMID:17222453

  20. 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

  1. [BIOLOGICAL IMPLANTS IN ABDOMINAL WALL HERNIA REPAIR (REVIEW)].

    PubMed

    Abatov, N; Badyrov, R; Abatova, A; Assamidanov, E; Kaukenov, B

    2016-02-01

    The use of synthetic meshes as a material for abdominal wall hernia repair does not always ensure a recurrence-free treatment outcome and full recovery of the abdominal wall functional activity. There are well-known disadvantages such as poor resistance to infection, the infiltrate formation in the place of implantation, expressed adhesive process in cases of introperitoneal fixation, to create certain restrictions on the using of these implants for abdominal wall reconstruction. The search for alternative materials that could minimize the risk of complications, has led to the study of biological grafts. It is known that various methods for the manufacturing biological implants determine endogenous properties for each material separately, and may be cause a variety of biological responses in vivo after implantation. The question has not been resolved, what the fresh raw material is better to use for derive biological implants. In this review we investigated the interaction of different types of biological implants between the abdominal wall and the organs of abdominal cavity of the recipient, their ability to resist infection and the development of relapses, as a leading indicator of the effectiveness of hernioplasty. PMID:27001778

  2. Abdominal sounds

    MedlinePlus

    ... during sleep. They also occur normally for a short time after the use of certain medicines and after abdominal surgery. Decreased or absent bowel sounds often indicate constipation. Increased ( hyperactive ) bowel sounds ...

  3. Abdominal MRI

    MedlinePlus

    ... provider if you have: Artificial heart valves Brain aneurysm clips Heart defibrillator or pacemaker Inner ear (cochlear) ... which the test may be performed: Abdominal aortic aneurysm Atheroembolic renal disease Carcinoma of the renal pelvis ...

  4. Abdominal pain

    MedlinePlus

    ... threatening conditions, such as colon cancer or early appendicitis , may only cause mild pain or no pain. ... Food poisoning Stomach flu Other possible causes include: Appendicitis Abdominal aortic aneurysm (bulging and weakening of the ...

  5. Abdominal Pain

    MedlinePlus

    ... can help the overall situation for the child. Teaching kids self-hypnosis [8] or guided imagery [8a] ... related topics? Functional Abdominal Pain (English, French or Spanish)—from The North American Society for Pediatric Gastroenterology, ...

  6. 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

  7. Phenylethanol promotes adhesion and biofilm formation of the antagonistic yeast Kloeckera apiculata for the control of blue mold on citrus.

    PubMed

    Pu, Liu; Jingfan, Fang; Kai, Chen; Chao-an, Long; Yunjiang, Cheng

    2014-06-01

    The yeast Kloeckera apiculata strain 34-9 is an antagonist with biological control activity against postharvest diseases of citrus fruit. In a previous study it was demonstrated that K. apiculata produced the aromatic alcohol phenylethanol. In the present study, we found that K. apiculata was able to form biofilm on citrus fruit and embed in an extracellular matrix, which created a mechanical barrier interposed between the wound surface and pathogen. As a quorum-sensing molecule, phenylethanol can promote the formation of filaments by K. apiculata in potato dextrose agar medium, whereas on the citrus fruit, the antagonist remains as yeast after being treated with the same concentration of phenylethanol. It only induced K. apiculata to adhere and form biofilm. Following genome-wide computational and experimental identification of the possible genes associated with K. apiculata adhesion, we identified nine genes possibly involved in triggering yeast adhesion. Six of these genes were significantly induced after phenylethanol stress treatment. This study provides a new model system of the biology of the antagonist-pathogen interactions that occur in the antagonistic yeast K. apiculata for the control of blue mold on citrus caused by Penicillium italicum. PMID:24479773

  8. Antibiofilm formation and anti-adhesive property of three mediterranean essential oils against a foodborne pathogen Salmonella strain.

    PubMed

    Miladi, Hanene; Mili, Donia; Ben Slama, Rihab; Zouari, Sami; Ammar, Emna; Bakhrouf, Amina

    2016-04-01

    Plant extracts, and their essential oils (EOs) are rich in a wide variety of secondary metabolites with antimicrobial properties. Our aim was to determine the bioactive compound in three mediterranean essential oils belonging to Lamiaceae family, Satureja montana L., Thymus vulgaris L. and Rosmarinus officinalis L., and to assess their antimicrobial, antibiofilm and anti-adhesive potentials against a foodborne pathogen Salmonella strain. The antibacterial activity of EOs and its biofilm inhibition potencies were investigated on 2 reference strains Salmonella typhimurium and 12 Salmonella spp. isolated from food. Biofilm inhibition were assessed using the 2, 3-bis [2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT) reduction assay. The analytical data indicated that various monoterpene hydrocarbons and phenolic monoterpenes constitute the major components of the oils, but their concentrations varied greatly among the oils examined. Our results showed that S. montana L. and T. vulgaris L. essential oils possess remarkable anti biofilm, anti-adhesive and bactericidal properties, compared to R. officinalis EO. There is an indication that Rosmary EO might inhibit biofilm formation at higher concentrations. Therefore, the witer savory and thyme EOs represent a source of natural compounds that exhibit potentials for use in food systems to prevent the growth of foodborne bacteria and extend the shelf life of the processed food. PMID:26802522

  9. Salusin-β induces foam cell formation and monocyte adhesion in human vascular smooth muscle cells via miR155/NOX2/NFκB pathway

    PubMed Central

    Sun, Hai-Jian; Zhao, Ming-Xia; Liu, Tong-Yan; Ren, Xing-Sheng; Chen, Qi; Li, Yue-Hua; Kang, Yu-Ming; Zhu, Guo-Qing

    2016-01-01

    Vascular smooth muscle cells (VSMCs) are indispensible components in foam cell formation. Salusin-β is a stimulator in the progression of atherosclerosis. Here, we showed that salusin-β increased foam cell formation evidenced by accumulation of lipid droplets and intracellular cholesterol content, and promoted monocyte adhesion in human VSMCs. Salusin-β increased the expressions and activity of acyl coenzyme A:cholesterol acyltransferase-1 (ACAT-1) and vascular cell adhesion molecule-1 (VCAM-1) in VSMCs. Silencing of ACAT-1 abolished the salusin-β-induced lipid accumulation, and silencing of VCAM-1 prevented the salusin-β-induced monocyte adhesion in VSMCs. Salusin-β caused p65-NFκB nuclear translocation and increased p65 occupancy at the ACAT-1 and VCAM-1 promoter. Inhibition of NFκB with Bay 11-7082 prevented the salusin-β-induced ACAT-1 and VCAM-1 upregulation, foam cell formation and monocyte adhesion in VSMCs. Scavenging ROS, inhibiting NADPH oxidase or knockdown of NOX2 abolished the effects of salusin-β on ACAT-1 and VCAM-1 expressions, p65-NFκB nuclear translocation, lipid accumulation and monocyte adhesion in VSMCs. Salusin-β increased miR155 expression, and knockdown of miR155 prevented the effects of salusin-β on ACAT-1 and VCAM-1 expressions, p65-NFκB nuclear translocation, lipid accumulation, monocyte adhesion and ROS production in VSMCs. These results indicate that salusin-β induces foam formation and monocyte adhesion via miR155/NOX2/NFκB-mediated ACAT-1 and VCAM-1 expressions in VSMCs. PMID:27004848

  10. Zinc Prevents Abdominal Aortic Aneurysm Formation by Induction of A20-Mediated Suppression of NF-κB Pathway.

    PubMed

    Yan, Ya-Wei; Fan, Jun; Bai, Shu-Ling; Hou, Wei-Jian; Li, Xiang; Tong, Hao

    2016-01-01

    Chronic inflammation and degradation of elastin are the main processes in the development of abdominal aortic aneurysm (AAA). Recent studies show that zinc has an anti-inflammatory effect. Based on these, zinc may render effective therapy for the treatment of the AAA. Currently, we want to investigate the effects of zinc on AAA progression and its related molecular mechanism. Rat AAA models were induced by periaortic application of CaCl2. AAA rats were treated by daily intraperitoneal injection of ZnSO4 or vehicle alone. The aorta segments were collected at 4 weeks after surgery. The primary rat aortic vascular smooth muscle cells (VSMCs) were stimulated with TNF-α alone or with ZnSO4 for 3 weeks. The results showed that zinc supplementation significantly suppressed the CaCl2-induced expansion of the abdominal aortic diameter, as well as a preservation of medial elastin fibers in the aortas. Zinc supplementation also obviously attenuated infiltration of the macrophages and lymphocytes in the aortas. In addition, zinc reduced MMP-2 and MMP-9 production in the aortas. Most importantly, zinc treatment significantly induced A20 expression, along with inhibition of the NF-κB canonical signaling pathway in vitro in VSMCs and in vivo in rat AAA. This study demonstrated, for the first time, that zinc supplementation could prevent the development of rat experimental AAA by induction of A20-mediated inhibition of the NF-κB canonical signaling pathway. PMID:26918963

  11. Zinc Prevents Abdominal Aortic Aneurysm Formation by Induction of A20-Mediated Suppression of NF-κB Pathway

    PubMed Central

    Bai, Shu-Ling; Hou, Wei-Jian; Li, Xiang; Tong, Hao

    2016-01-01

    Chronic inflammation and degradation of elastin are the main processes in the development of abdominal aortic aneurysm (AAA). Recent studies show that zinc has an anti-inflammatory effect. Based on these, zinc may render effective therapy for the treatment of the AAA. Currently, we want to investigate the effects of zinc on AAA progression and its related molecular mechanism. Rat AAA models were induced by periaortic application of CaCl2. AAA rats were treated by daily intraperitoneal injection of ZnSO4 or vehicle alone. The aorta segments were collected at 4 weeks after surgery. The primary rat aortic vascular smooth muscle cells (VSMCs) were stimulated with TNF-α alone or with ZnSO4 for 3 weeks. The results showed that zinc supplementation significantly suppressed the CaCl2-induced expansion of the abdominal aortic diameter, as well as a preservation of medial elastin fibers in the aortas. Zinc supplementation also obviously attenuated infiltration of the macrophages and lymphocytes in the aortas. In addition, zinc reduced MMP-2 and MMP-9 production in the aortas. Most importantly, zinc treatment significantly induced A20 expression, along with inhibition of the NF-κB canonical signaling pathway in vitro in VSMCs and in vivo in rat AAA. This study demonstrated, for the first time, that zinc supplementation could prevent the development of rat experimental AAA by induction of A20-mediated inhibition of the NF-κB canonical signaling pathway. PMID:26918963

  12. Role of Aeromonas hydrophila Flagella Glycosylation in Adhesion to Hep-2 Cells, Biofilm Formation and Immune Stimulation

    PubMed Central

    Merino, Susana; Wilhelms, Markus; Tomás, Juan M.

    2014-01-01

    Abstract: Polar flagellin proteins from Aeromonas hydrophila strain AH-3 (serotype O34) were found to be O-glycosylated with a heterogeneous heptasaccharide glycan. Two mutants with altered (light and strong) polar flagella glycosylation still able to produce flagella were previously obtained, as well as mutants lacking the O34-antigen lipopolysaccharide (LPS) but with unaltered polar flagella glycosylation. We compared these mutants, altogether with the wild type strain, in different studies to conclude that polar flagella glycosylation is extremely important for A. hydrophila adhesion to Hep-2 cells and biofilm formation. Furthermore, the polar flagella glycosylation is an important factor for the immune stimulation of IL-8 production via toll receptor 5 (TLR5). PMID:25464381

  13. Abdominal Sepsis.

    PubMed

    De Waele, Jan J

    2016-08-01

    Abdominal infections are an important challenge for the intensive care physician. In an era of increasing antimicrobial resistance, selecting the appropriate regimen is important and, with new drugs coming to the market, correct use is important more than ever before and abdominal infections are an excellent target for antimicrobial stewardship programs. Biomarkers may be helpful, but their exact role in managing abdominal infections remains incompletely understood. Source control also remains an ongoing conundrum, and evidence is increasing that its importance supersedes the impact of antibiotic therapy. New strategies such as open abdomen management may offer added benefit in severely ill patients, but more data are needed to identify its exact role. The role of fungi and the need for antifungal coverage, on the other hand, have been investigated extensively in recent years, but at this point, it remains unclear who requires empirical as well as directed therapy. PMID:27363829

  14. Dynamic effects in friction and adhesion through cooperative rupture and formation of supramolecular bonds

    NASA Astrophysics Data System (ADS)

    Blass, Johanna; Albrecht, Marcel; Bozna, Bianca L.; Wenz, Gerhard; Bennewitz, Roland

    2015-04-01

    We introduce a molecular toolkit for studying the dynamics in friction and adhesion from the single molecule level to effects of multivalency. As experimental model system we use supramolecular bonds established by the inclusion of ditopic adamantane connector molecules into two surface-bound cyclodextrin molecules, attached to a tip of an atomic force microscope (AFM) and to a flat silicon surface. The rupture force of a single bond does not depend on the pulling rate, indicating that the fast complexation kinetics of adamantane and cyclodextrin are probed in thermal equilibrium. In contrast, the pull-off force for a group of supramolecular bonds depends on the unloading rate revealing a non-equilibrium situation, an effect discussed as the combined action of multivalency and cantilever inertia effects. Friction forces exhibit a stick-slip characteristic which is explained by the cooperative rupture of groups of host-guest bonds and their rebinding. No dependence of friction on the sliding velocity has been observed in the accessible range of velocities due to fast rebinding and the negligible delay of cantilever response in AFM lateral force measurements.We introduce a molecular toolkit for studying the dynamics in friction and adhesion from the single molecule level to effects of multivalency. As experimental model system we use supramolecular bonds established by the inclusion of ditopic adamantane connector molecules into two surface-bound cyclodextrin molecules, attached to a tip of an atomic force microscope (AFM) and to a flat silicon surface. The rupture force of a single bond does not depend on the pulling rate, indicating that the fast complexation kinetics of adamantane and cyclodextrin are probed in thermal equilibrium. In contrast, the pull-off force for a group of supramolecular bonds depends on the unloading rate revealing a non-equilibrium situation, an effect discussed as the combined action of multivalency and cantilever inertia effects. Friction

  15. A role for the WH-30 protein in sperm-sperm adhesion during rouleaux formation in the guinea pig.

    PubMed

    Flaherty, S P; Swann, N J; Primakoff, P; Myles, D G

    1993-03-01

    Mammalian spermatozoa participate in specific cell adhesion phenomena during their development and functional lifespan; this includes interaction with Sertoli cells, the zona pellucida, and the oolemma. In some species such as the guinea pig, an additional sperm-sperm adhesion occurs during epididymal maturation which results in the formation of rouleaux in which the sperm heads are stacked one upon the other and the periacrosomal plasma membranes of adjacent sperm are linked by periodic cross-bridges. In this study, we have used a monoclonal antibody to investigate the role of the WH-30 protein on the sperm surface in the formation of the junctional zones between adjacent guinea pig sperm in rouleaux. WH-30 monoclonal antibodies caused a dose- and time-dependent dissociation of rouleaux and an increase in the percentage of single, acrosome-intact sperm; there were no effects on sperm motility (maintained at 80-90%) or ultrastructure during the 120-min incubations. The maximal effect of about 80% single sperm was obtained with a 1:4 dilution of the WH-30 hybridoma supernatant or 5-50 micrograms/ml of purified WH-30 IgG. In contrast, incubation of sperm in AH-20 IgG, myeloma cell supernatants, or purified, nonspecific mouse IgG1 had no effect on rouleaux. Treatment of sperm with a WH-30 Fab fragment resulted in almost complete dissociation of rouleaux without any observed effect on sperm motility or acrosomal status. Surface labeling of sperm followed by immunoprecipitation and SDS-PAGE revealed that the WH-30 antibody recognizes a single polypeptide of 43-45 kDa. Using immunofluorescence, the WH-30 protein was localized over the entire surface of the sperm head (whole-head pattern), and immunogold labeling showed that WH-30 is localized in the glycocalyx on both the dorsal and ventral surfaces of the periacrosomal and postacrosomal plasma membranes. These results indicate that the WH-30 protein on the sperm surface is a cell adhesion protein which is involved in

  16. Dynamic effects in friction and adhesion through cooperative rupture and formation of supramolecular bonds.

    PubMed

    Blass, Johanna; Albrecht, Marcel; Bozna, Bianca L; Wenz, Gerhard; Bennewitz, Roland

    2015-05-01

    We introduce a molecular toolkit for studying the dynamics in friction and adhesion from the single molecule level to effects of multivalency. As experimental model system we use supramolecular bonds established by the inclusion of ditopic adamantane connector molecules into two surface-bound cyclodextrin molecules, attached to a tip of an atomic force microscope (AFM) and to a flat silicon surface. The rupture force of a single bond does not depend on the pulling rate, indicating that the fast complexation kinetics of adamantane and cyclodextrin are probed in thermal equilibrium. In contrast, the pull-off force for a group of supramolecular bonds depends on the unloading rate revealing a non-equilibrium situation, an effect discussed as the combined action of multivalency and cantilever inertia effects. Friction forces exhibit a stick-slip characteristic which is explained by the cooperative rupture of groups of host-guest bonds and their rebinding. No dependence of friction on the sliding velocity has been observed in the accessible range of velocities due to fast rebinding and the negligible delay of cantilever response in AFM lateral force measurements. PMID:25833225

  17. Abdominal thrusts

    MedlinePlus

    ... call 911 . If the person loses consciousness, start CPR . If you are not comfortable performing abdominal thrusts, ... American Red Cross. First Aid/CPR/AED Participant's Manual. 2nd ... Red Cross; 2014. Berg RA, Hemphill R, Abella BS, et al. Part 5: ...

  18. Formative Assessment as Educational and Administrative Adhesive: Establishing an Elementary School Writing Center.

    ERIC Educational Resources Information Center

    Wilcox, Brad; Black, Sharon; Anstead, Marcia Howell

    1997-01-01

    Describes the collaboration between a university and an elementary school to establish a writing center at the elementary school, staffed by university students (preservice teachers). Describes the crucial role of ongoing formative assessment activity for both elementary students and the university preservice teachers. (SR)

  19. Femtosecond laser surface texturing of titanium as a method to reduce the adhesion of Staphylococcus aureus and biofilm formation

    NASA Astrophysics Data System (ADS)

    Cunha, Alexandre; Elie, Anne-Marie; Plawinski, Laurent; Serro, Ana Paula; Botelho do Rego, Ana Maria; Almeida, Amélia; Urdaci, Maria C.; Durrieu, Marie-Christine; Vilar, Rui

    2016-01-01

    The aim of the present work was to investigate the possibility of using femtosecond laser surface texturing as a method to reduce the colonization of Grade 2 Titanium alloy surfaces by Staphylococcus aureus and the subsequent formation of biofilm. The laser treatments were carried out with a Yb:KYW chirped-pulse-regenerative amplification laser system with a central wavelength of 1030 nm and a pulse duration of 500 fs. Two types of surface textures, consisting of laser-induced periodic surface structures (LIPSS) and nanopillars, were produced. The topography, chemical composition and phase constitution of these surfaces were investigated by atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, micro-Raman spectroscopy, and X-ray diffraction. Surface wettability was assessed by the sessile drop method using water and diiodomethane as testing liquids. The response of S. aureus put into contact with the laser treated surfaces in controlled conditions was investigated by epifluorescence microscopy and scanning electron microscopy 48 h after cell seeding. The results achieved show that the laser treatment reduces significantly the bacterial adhesion to the surface as well as biofilm formation as compared to a reference polished surfaces and suggest that femtosecond laser texturing is a simple and promising method for endowing dental and orthopedic titanium implants with antibacterial properties, reducing the risk of implant-associated infections without requiring immobilized antibacterial substances, nanoparticles or coatings.

  20. Injectable pullulan hydrogel for the prevention of postoperative tissue adhesion.

    PubMed

    Bang, Sumi; Lee, Eungjae; Ko, Young-Gwang; Kim, Won Il; Kwon, Oh Hyeong

    2016-06-01

    Methods for reducing and preventing postoperative abdominal adhesions have been researched for decades; however, despite these efforts, the formation of postoperative peritoneal adhesions is continuously reported. Adhesions cause serious complications such as postoperative pain, intestinal obstruction, and infertility. Tissue adhesion barriers have been developed as films, membranes, knits, sprays, and hydrogels. Hydrogels have several advantages when used as adhesion barriers, including flexibility, low tissue adhesiveness, biodegradability, and non-toxic degraded products. Furthermore, compared with preformed hydrogels, injectable hydrogels can fill and cover spaces of any shape and do not require a surgical procedure for implantation. In this study, pullulan was modified through reaction with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) to introduce carboxyl and phenyl groups as crosslinking sites. The grafting of tyramine on pullulan allows crosslinking branches on pullulan backbone. We successfully fabricated pullulan hydrogel with an enzymatic reaction using horseradish peroxidase (HRP) and hydrogen peroxide (H2O2). The chemical structure of modified pullulan was analyzed with ATR-FTIR and (1)H NMR spectroscopies. Rheological properties were tested by measuring storage modulus with varying H2O2, HRP, polymer solution concentrations and tyramine substitution rates. Cell viability and animal tests were performed. The modified pullulan hydrogel is an invaluable advance in anti-adhesion agents. PMID:26879910

  1. Abdominal Aortic Aneurysms: Treatments

    MedlinePlus

    ... information Membership Directory (SIR login) Interventional Radiology Abdominal Aortic Aneurysms Interventional Radiologists Treat Abdominal Aneurysms Nonsurgically Interventional radiologists ...

  2. Mammary gland-specific ablation of focal adhesion kinase reduces the incidence of p53-mediated mammary tumour formation

    PubMed Central

    van Miltenburg, M H A M; van Nimwegen, M J; Tijdens, I; Lalai, R; Kuiper, R; Klarenbeek, S; Schouten, P C; de Vries, A; Jonkers, J; van de Water, B

    2014-01-01

    Background: Elevated expression of focal adhesion kinase (FAK) occurs in numerous human cancers including colon-, cervix- and breast cancer. Although several studies have implicated FAK in mammary tumour formation induced by ectopic oncogene expression, evidence supporting a role for FAK in spontaneous mammary tumour development caused by loss of tumour suppressor genes such as p53 is lacking. Alterations in the tumour suppressor gene p53 have been implicated in over 50% of human breast cancers. Given that elevated FAK expression highly correlates with p53 mutation status in human breast cancer, we set out to investigate the importance of FAK in p53-mediated spontaneous mammary tumour development. Methods: To directly assess the role of FAK, we generated mice with conditional inactivation of FAK and p53. We generated female p53lox/lox/FAK+/+/WapCre, p53lox/lox/FAKflox/+/WapCre and p53lox/lox/FAKflox/−/WapCre mice, and mice with WapCre-mediated conditional expression of p53R270H, the mouse equivalent of human p53R273H hot spot mutation, together with conditional deletion of FAK, P53R270H/+/FAKlox/+/WapCre and p53R270H/+/FAKflox/−/WapCre mice. All mice were subjected to one pregnancy to induce WapCre-mediated deletion of p53 or expression of p53 R270H, and Fak genes flanked by two loxP sites, and subsequently followed the development of mammary tumours. Results: Using this approach, we show that FAK is important for p53-induced mammary tumour development. In addition, mice with the mammary gland-specific conditional expression of p53 point mutation R270H, the mouse equivalent to human R273H, in combination with conditional deletion of Fak showed reduced incidence of p53R270H-induced mammary tumours. In both models these effects of FAK were related to reduced proliferation in preneoplastic lesions in the mammary gland ductal structures. Conclusions: Mammary gland-specific ablation of FAK hampers p53-regulated spontaneous mammary tumour formation. Focal adhesion

  3. 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

  4. Addition of surfactants in ozonated water cleaning for the suppression of functional group formation and particle adhesion on the SiO2 surface

    NASA Astrophysics Data System (ADS)

    Yang, Jahyun; Im, Kyungtaek; Lim, Sangwoo

    2011-04-01

    Various kinds of surfactants were added to a cleaning solution and deionized (DI) water, and their effect on the suppression of organic function group formation and particle adhesion to a SiO2 surface was analyzed using multi-internal reflection Fourier transform infrared spectroscopy. The results implied that attached organic functional groups are affected by the chemical structure of a surfactant in DI water. Furthermore, the addition of anionic glycolic acid ethoxylate 4-tert-butylphenyl ether (GAE4E) is the most effective in terms of preventing organic group attachment and particle adhesion to the SiO2 surface, whether it was added to the cleaning solution or post-cleaning rinse water, with or without polystyrene latex particles. Moreover, it was possible to completely prevent particle adhesion to the SiO2 surface with the proper addition of GAE4E in DIO3 solution.

  5. Effect of ankaferd blood stopper in experimental peritoneal adhesion model

    PubMed Central

    Aydin, Oktay; Pehlivanli, Faruk; Kocael, Ahmet; Pekcici, Recep; Duymus, Esat; Akgedik, Sukran; Guler, Osman

    2016-01-01

    Purpose Ankaferd Blood Stopper (ABS) is an herbal extract attained from 5 different plants. It has the therapeutic potential to be used for the management of external hemorrhage and controlling gastrointestinal bleedings. To date, the safety of ABS for intraperitoneal usage is not clear. In this study, we investigated the effectiveness and safety of using intraperitoneal ABS in an experimental peritoneal adhesion model. Methods Twenty-four male Wistar Albino rats were used in the study. The rats were randomly divided into 3 groups: saline, ABS, and control. On the 10th day, all rats were euthanized. The adhesions were evaluated by Nair's macroscopic adhesion classification, and pathologically evaluated with Zühlke's microscopic adhesion classification. Results macroscopic and microscopic comparison between the ABS and saline groups did not show any differences but both the ABS and saline groups were superior when compared to the control group. Conclusion ABS was found equally effective with saline on the abdominal adhesions and to no effect on postoperative adhesion formation. PMID:27073792

  6. Influence of the monomer structure and electrochemical parameters on the formation of nanotubes with parahydrophobic properties (high water adhesion) by a templateless electropolymerization process.

    PubMed

    Darmanin, Thierry; Laugier, Jean-Pierre; Orange, François; Guittard, Frédéric

    2016-03-15

    Controlling the formation of surface nanostructures and nanotubes in particular is extremely important for various applications in electronic devices for energy systems, biosensing but also for the control of water adhesion. Here, we use a direct (without template) electropolymerization process to produce vertically aligned nanotubes. Different monomers are tested as well as different solvents, electrolytes and electrodeposition methods. We show that naphtho[2,3-b]thieno[3,4-e][1,4]dioxine (NaphDOT) is the best monomer to obtain these nanotubes while dichloromethane has to be used as solvent for their formation. The surfaces with nanotubes display both extremely high apparent contact angles (θ(w)=142.7°) and high water adhesion even if the nanotubes are made of intrinsically hydrophilic polymers and are not densely packed. PMID:26771504

  7. Human T-cell lymphotropic virus type 1 (HTLV-1)-induced syncytium formation mediated by vascular cell adhesion molecule-1: evidence for involvement of cell adhesion molecules in HTLV-1 biology.

    PubMed Central

    Hildreth, J E; Subramanium, A; Hampton, R A

    1997-01-01

    While studying the potential role of vascular cell adhesion molecule-1 (VCAM-1) in infection of endothelial cells by human immunodeficiency virus (HIV), we found that VCAM-1 can mediate human T-cell lymphotropic virus type 1 (HTLV-1)-induced syncytium formation. Both expression-vector-encoded and endogenously expressed VCAM-1 supported fusion of uninfected cells with HTLV-1-infected cells. Fusion was obtained with cell lines carrying the HTLV-1 genome and expressing viral proteins but not with an HTLV-1-transformed cell line that does not express viral proteins. In clones of VCAM-1-transfected cells, the degree of syncytium formation observed directly reflected the level of VCAM-1 expression. Syncytium formation between HTLV-1-expressing cells and VCAM-1+ cells could be blocked with antiserum against HTLV-1 gp46 and with a monoclonal antibody (MAb) against VCAM-1. Fusion was not blocked by antiserum against HIV or a MAb against VLA-4, the physiological counter-receptor for VCAM-1. The results indicate that VCAM-1 can serve as an accessory molecule or potential coreceptor for HTLV-1-induced cell fusion and provide direct evidence of a role for cell adhesion molecules in the biology of HTLV-1. PMID:8995639

  8. [A case of abdominal wall actinomycosis].

    PubMed

    Kim, Kyung Hoon; Lee, Jin Soo; Cho, Hyeong Jun; Choi, Seung Bong; Cheung, Dae Young; Kim, Jin Il; Lee, In Kyu

    2015-04-01

    Actinomycosis is a chronic suppurative granulomatous infectious disease caused by actinomyces species that is characterized by formation of characteristic clumps called as sulfur granules. Abdominal actinomycosis is a rare disease and is often difficult to diagnose before operation. Abdominal actinomycosis infiltrating into the abdominal wall and adhering to the colon is even rarer. Most abdominal actinomycosis develops after operation, trauma or inflammatory bowel disease, and is also considered as an opportunistic infection in immunocompromised patient with underlying malignancy, diabetes mellitus, human immunodeficiency virus infection, etc. Actinomycosis is diagnosed based on histologic demonstration of sulfur granules in surgically resected specimen or pus, and treatment consists of long-term penicillin based antibiotics therapy with or without surgical resection. Herein, we report an unusual case of abdominal wall actinomycosis which developed in a patient after acupuncture and presented as abdominal wall mass that was first mistaken for abdominal wall invasion of diverticulum perforation. PMID:25896158

  9. Efficacy and Safety of Sodium Hyaluronate with 1,4-Butanediol Diglycidyl Ether Compared to Sodium Carboxymethylcellulose in Preventing Adhesion Formation after Lumbar Discectomy

    PubMed Central

    Ji, Gyu Yeul; Oh, Chang Hyun; Moon, Byung Gwan; Yi, Seong; Han, In Bo; Heo, Dong Hwa; Kim, Ki-Tack; Kim, Keung Nyun

    2015-01-01

    Objective Epidural injection of hyaluronic acid may prevent adhesion formation after spine surgery, but the compounds used to stabilize hyaluronidase could interfere with its anti-adhesion effects. The present study was conducted as a clinical trial to evaluate the efficacy and safety of an experimental medical gel in preventing adhesion formation. Methods This study was designed as a multicenter, randomized, double-blind, and comparative controlled clinical trial with an observation period of 6 weeks. Subjects were randomly assigned into two groups: group A with sodium hyaluronate + 1,4-butanediol diglycidyl ether (BDDE) and group B with sodium hyaluronate + sodium carboxymethylcellulose (CMC). Visual analogue scale (VAS) of back and leg pain and the Oswestry disability index (ODI) and scar score ratings were assessed after surgery. Results Mean scar grade was 2.37±1.13 in group A and 2.75±0.97 in group B, a statistically significant difference (p=0.012). VAS of back and leg pain and ODI scores decreased significantly from baseline to 3 and 6 weeks postoperatively in both groups (p<0.001). However, VAS and ODI scores were not statistically different between groups A and B at baseline or at 3 and 6 weeks after operation (p>0.3). The number of adverse reactions related to the anti-adhesion gels was not statistically different (p=0.569), but subsequent analysis of nervous adverse reactions showed group B was superior with a statistically difference (p=0.027). Conclusion Sodium hyaluronate with BDDE demonstrated similar anti-adhesion properties to sodium hyaluronate with CMC. But, care should be used to nervous adverse reactions by using sodium hyaluronate with BDDE. PMID:26217381

  10. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... Resources Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis ... aortic aneurysm treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, ...

  11. Abdominal CT scan

    MedlinePlus

    ... results may also be due to: Abdominal aortic aneurysm Abscesses Appendicitis Bowel wall thickening Retroperitoneal fibrosis Renal ... Livingstone; 2014:chap 4. Read More Abdominal aortic aneurysm Abdominal aortic aneurysm repair - open Abscess Acute cholecystitis ...

  12. Large-scale gas dynamics in the adhesion model: implications for the two-phase massive galaxy formation scenario

    NASA Astrophysics Data System (ADS)

    Domínguez-Tenreiro, R.; Oñorbe, J.; Martínez-Serrano, F.; Serna, A.

    2011-06-01

    We have studied the mass assembly and star formation histories of massive galaxies identified at low redshift in different cosmological hydrodynamical simulations. To this end, we have carried out a detailed follow-up backwards in time of their constituent mass elements (sampled by particles) of different types. After that, the configurations they depict at progressively higher zs were carefully analysed. The analyses show that these histories share common generic patterns, irrespective of particular circumstances. In any case, however, the results we have found are different depending on the particle type. The most outstanding differences follow. We have found that by z˜ 3.5-6, mass elements identified as stellar particles at z= 0 exhibit a gaseous cosmic-web-like morphology with scales of ˜1 physical Mpc, where the densest mass elements have already turned into stars by z˜ 6. These settings are in fact the densest pieces of the cosmic web, where no hot particles show up, and dynamically organized as a hierarchy of flow convergence regions (FCRs), that is, attraction basins for mass flows. At high z FCRs undergo fast contractive deformations with very low angular momentum, shrinking them violently. Indeed, by z˜ 1 most of the gaseous or stellar mass they contain shows up as bound to a massive elliptical-like object at their centres, with typical half-mass radii of rmassstar˜ 2-3 kpc. After this, a second phase comes about where the mass assembly rate is much slower and characterized by mergers involving angular momentum. On the other hand, mass elements identified at the diffuse hot coronae surrounding massive galaxies at z= 0 do not display a clear web-like morphology at any z. Diffuse gas is heated when FCRs go through contractive deformations. Most of this gas remains hot and with low density throughout the evolution. To shed light on the physical foundations of the behaviour revealed by our analyses (i.e. a two-phase formation process with different

  13. 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.

  14. Deficiency of endogenous acute phase serum amyloid A protects apoE−/− mice from angiotensin II-induced abdominal aortic aneurysm formation

    PubMed Central

    Webb, NR; De Beer, MC; Wroblewski, JM; Ji, A; Bailey, W; Shridas, P; Charnigo, RJ; Noffsinger, VP; Witta, J; Howatt, DA; Balakrishnan, A; Rateri, DL; Daugherty, A; De Beer, FC

    2016-01-01

    Objective Rupture of abdominal aortic aneurysm (AAA), a major cause of death in the aged population, is characterized by vascular inflammation and matrix degradation. Serum amyloid A (SAA), an acute phase reactant linked to inflammation and matrix metalloproteinase induction, correlates with aortic dimensions before aneurysm formation in humans. We investigated whether SAA deficiency in mice impacts AAA formation during angiotensin II (AngII) infusion. Approach and Results Plasma SAA increased ~60-fold in apoE−/− mice 24 hours after i.p. AngII injection (100 μg/kg; n = 4) and ~15-fold after chronic 28-day AngII infusion (1,000 ng/kg/min; n = 9). AAA incidence and severity after 28-day AngII infusion was significantly reduced in apoE−/− mice lacking both acute phase SAA isoforms (SAAKO; n = 20) compared to apoE−/− mice (SAAWT; n = 20) as assessed by in vivo ultrasound and ex vivo morphometric analyses, despite a significant increase in systolic blood pressure in SAAKO mice compared to SAAWT mice after AngII infusion. Atherosclerotic lesion area of the aortic arch was similar in SAAKO and SAAWT mice after 28-day AngII infusion. Immunostaining detected SAA in AAA tissues of AngII-infused SAAWT mice that co-localized with macrophages, elastin breaks, and enhanced matrix metalloproteinase (MMP) activity. MMP-2 activity was significantly lower in aortas of SAAKO mice compared to SAAWT mice after 10-day AngII infusion. Conclusion Lack of endogenous acute phase SAA protects against experimental AAA through a mechanism that may involve reduced MMP-2 activity. PMID:25745063

  15. Adeno-associated virus-2-mediated TGF-β1 microRNA transfection inhibits adhesion formation after digital flexor tendon injury.

    PubMed

    Wu, Y F; Mao, W F; Zhou, Y L; Wang, X T; Liu, P Y; Tang, J B

    2016-02-01

    Adhesion formation after digital flexor tendon injury greatly affects gliding function of the tendon, which is a major clinical complication after hand surgery. Transforming growth factor beta 1 (TGF-β1) has a critical role in adhesion formation during tendon healing. Persistent regulation of TGF-β1 through application of microRNA (miRNA) specifically inhibiting the function of TGF-β1 (TGF-β1-miRNA) holds promise for treatment of such a complication. Adeno-associated virus (AAV) was used to transfer TGF-β1-miRNA to the chicken digital flexor tendons, which had been injured and surgically repaired. Four doses of AAV2-TGF-β1-miRNA (2 × 10(11), 2 × 10(10), 2 × 10(9) and 2 × 10(8) vector genomes (vg)) were used to determine the transfection efficiency. At postoperative 3 weeks, we found a positive correlation between the administered AAV2-TGF-β1-miRNA doses and transfection efficiency. The transfection rate ranged from 10% to 77% as the doses increased. Production of TGF-β1 protein in the tendons decreased on increasing vector dosage. When 2 × 10(11) and 2 × 10(10) vg were injected into the tendon, gliding excursion of the repaired tendon and work of flexion of chicken toes were significantly increased and adhesion score decreased 6 and 8 weeks later, indicating the improvement of tendon gliding and decreases in adhesion formations. However, the ultimate strength of the tendons transfected at the dose of 2 × 10(10) vg was 12-24% lower than that of the control tendons. The results of this study demonstrate that application of TGF-β1-miRNA had a mixed impact on tendon healing: adhesion around the tendon is reduced but strength of the tendon healing is adversely affected. Future studies should aim at maintaining the beneficial effects of reducing tendon adhesions, while eliminating the adverse effects of decreasing the healing strength. PMID:26381218

  16. The influence of mesh topology in the abdominal wall repair process.

    PubMed

    De Maria, Carmelo; Burchielli, Silvia; Salvadori, Claudia; Santoro, Vito; Montemurro, Francesca; Orsi, Gianni; Vozzi, Giovanni

    2016-08-01

    The tissue integration and the formation of adhesions in the repair of abdominal wall defects are principally led to the topology and the mechanical properties of implanted prosthesis. In this study we analyzed the influence of the topology of the meshes for abdominal wall repair, made of polypropylene (PP), evaluating its ability to prevent and to minimize the formation of adhesions, and to promote tissue ingrowth. Two series of in vivo studies were performed. In the first, two types of PP meshes, a lightweight macroporous mesh (LWM) and a heavyweight microporous mesh (HWM) were compared with determine the optimal porosity for tissue integration. In the second, a composite mesh, Clear Mesh Composite (CMC), made of a LWM sewn on a PP planar smooth film, was compared with a PP planar film, to demonstrate how two different topologies of same material are able to induce different tissue integration with the abdominal wall and different adhesion with internal organs. In both studies, the prostheses were implanted in Wistar rats and histological analysis and mechanical characterization of tissue coupled with the implants were performed. LWM showed better host tissue ingrowth in comparison to HWM. CMC prosthesis showed no adhesions to the viscera and no strong foreign body reaction, moreover its elasticity and anisotropy index were more similar to that of natural tissue. These results demonstrated that the surface morphology of PP surgical meshes allowed to modulate their repair ability. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1220-1228, 2016. PMID:26097153

  17. Introduction of p130cas signaling complex formation upon integrin-mediated cell adhesion: a role for Src family kinases.

    PubMed Central

    Vuori, K; Hirai, H; Aizawa, S; Ruoslahti, E

    1996-01-01

    Integrin-mediated cell adhesion triggers intracellular signaling cascades, including tyrosine phosphorylation of intracellular proteins. Among these are the focal adhesion proteins p130cas (Cas) and focal adhesion kinase (FAK). Here we identify the kinase(s) mediating integrin-induced Cas phosphorylation and characterize protein-protein interactions mediated by phosphorylated Cas. We found that expression of a constitutively active FAK in fibroblasts results in a consecutive tyrosine phosphorylation of Cas. This effect required the autophosphorylation site of FAK, which is a binding site for Src family kinases. Integrin-mediated phosphorylation of Cas was not, however, compromised in fibroblasts lacking FAK. In contrast, adhesion-induced tyrosine phosphorylation of Cas was reduced in cells lacking Src, whereas enhanced phosphorylation of Cas was observed Csk- cells, in which Src kinases are activated. These results suggest that Src kinases are responsible for the integrin-mediated tyrosine phosphorylation of Cas. FAK seems not to be necessary for phosphorylation of Cas, but when autophosphorylated, FAK may recruit Src family kinases to phosphorylate Cas. Cas was found to form complexes with Src homology 2 (SH2) domain-containing signaling molecules, such as the SH2/SH3 adapter protein Crk, following integrin-induced tyrosine phosphorylation. Guanine nucleotide exchange factors C3G and Sos were found in the Cas-Crk complex upon integrin ligand binding. These observations suggest that Cas serves as a docking protein and may transduce signals to downstream signaling pathways following integrin-mediated cell adhesion. PMID:8649368

  18. GPVI and α2β1 play independent critical roles during platelet adhesion and aggregate formation to collagen under flow

    PubMed Central

    Sarratt, Kendra L.; Chen, Hong; Zutter, Mary M.; Santoro, Samuel A.; Hammer, Daniel A.; Kahn, Mark L.

    2005-01-01

    The roles of the 2 major platelet-collagen receptors, glycoprotein VI (GPVI) and integrin α2β1, have been intensely investigated using a variety of methods over the past decade. In the present study, we have used pharmacologic and genetic approaches to study human and mouse platelet adhesion to collagen under flow conditions. Our studies demonstrate that both GPVI and integrin α2β1 play significant roles for platelet adhesion to collagen under flow and that the loss of both receptors completely ablates this response. Intracellular signaling mediated by the cytoplasmic adaptor Src homology 2 domain-containing leukocyte protein of 76 kDa (SLP-76) but not by the transmembrane adaptor linker for activation of T cells (LAT) is critical for platelet adhesion to collagen under flow. In addition, reduced GPVI receptor density results in severe defects in platelet adhesion to collagen under flow. Defective adhesion to collagen under flow is associated with prolonged tail-bleeding times in mice lacking one or both collagen receptors. These studies establish platelet-collagen responses under physiologic flow as the consequence of a close partnership between 2 structurally distinct receptors and suggest that both receptors play significant hemostatic roles in vivo. PMID:15886326

  19. Simultaneous formation of fine and large-area electrode patterns using screen-offset printing and its application to the patterning on adhesive materials

    NASA Astrophysics Data System (ADS)

    Nomura, Ken-ichi; Ushijima, Hirobumi; Nagase, Kazuro; Ikedo, Hiroaki; Mitsui, Ryosuke; Sato, Junya; Takahashi, Seiya; Nakajima, Shin-ichiro; Arai, Masahiro; Kurata, Yuji; Iwata, Shiro

    2016-03-01

    Additive-type printing techniques such as gravure-offset printing and screen printing are effective for low-cost and ecofriendly electrode pattern formation. Gravure-offset printing is effective for fine pattern formation with widths on the order of 10-20 µm, whereas screen printing is effective for the formation of large-area patterns. However, it is difficult to simultaneously form fine and large-area patterns using these printing techniques. In this study, we demonstrate that fine (minimum width of 15 µm) and medium- as well as large-area patterns can be formed simultaneously using our developed screen-offset printing technique, which is a combination of screen printing on a silicone blanket and transfer printing from the blanket to a substrate. Furthermore, we demonstrate the application of our method to printing on adhesive materials, which allows electrode formation without applying heat to the film substrate.

  20. Apigenin inhibits platelet adhesion and thrombus formation and synergizes with aspirin in the suppression of the arachidonic acid pathway.

    PubMed

    Navarro-Núñez, L; Lozano, M L; Palomo, M; Martínez, C; Vicente, V; Castillo, J; Benavente-García, O; Diaz-Ricart, M; Escolar, G; Rivera, J

    2008-05-14

    Previous studies using washed platelets demonstrated that certain flavonoids inhibit platelet function through several mechanisms including blockade of TxA(2) receptors (TPs). We aimed to analyze the binding capacity of flavonoids to TPs in platelet rich plasma (PRP), investigated their effect in flowing blood, and evaluated the ability of apigenin to improve the efficacy of aspirin in the inhibition of platelet aggregation. The binding of flavonoids to TPs in PRP was explored using binding assays and the TP antagonist [ (3)H]SQ29548. Effects of flavonoids on platelet adhesion were assessed using arterial subendothelium with annular plate perfusion chambers, and global evaluation of apigenin on high-shear-dependent platelet function was determined by the PFA-100. To evaluate the ability of apigenin to potentiate the effect of aspirin, arachidonic acid-induced platelet aggregation was measured prior to and after consumption of subaggregatory doses of aspirin in the presence or absence of apigenin. Binding assays revealed that apigenin was an efficient competitor of [ (3)H]SQ29548 binding to PRP ( K i = 155.3 +/- 65.4 microM), and perfusion studies showed that apigenin, genistein, and catechin significantly diminished thrombus formation when compared to control (26.2 +/- 3.8, 33.1 +/- 5.2, and 26.2 +/- 5.2 vs 76.6 +/- 2.6%, respectively; p < 0.05). Apigenin, similarly to the TP antagonist SQ29548, significantly prolonged collagen epinephrine-induced PFA-100 closure time in comparison to the control and, when added to platelets that had been exposed in vivo to aspirin, potentiated its inhibitory effect on platelet aggregation. The inhibitory effect of some flavonoids in the presence of plasma, particularly apigenin, might in part rely on TxA(2) receptor antagonism. There is a clear increase in the ex vivo antiplatelet effect of aspirin in the presence of apigenin, which encourages the idea of the combined use of aspirin and certain flavonoids in patients in which

  1. A role for the retinoblastoma protein as a regulator of mouse osteoblast cell adhesion: implications for osteogenesis and osteosarcoma formation.

    PubMed

    Sosa-García, Bernadette; Gunduz, Volkan; Vázquez-Rivera, Viviana; Cress, W Douglas; Wright, Gabriela; Bian, Haikuo; Hinds, Philip W; Santiago-Cardona, Pedro G

    2010-01-01

    The retinoblastoma protein (pRb) is a cell cycle regulator inactivated in most human cancers. Loss of pRb function results from mutations in the gene coding for pRb or for any of its upstream regulators. Although pRb is predominantly known as a cell cycle repressor, our data point to additional pRb functions in cell adhesion. Our data show that pRb regulates the expression of a wide repertoire of cell adhesion genes and regulates the assembly of the adherens junctions required for cell adhesion. We conducted our studies in osteoblasts, which depend on both pRb and on cell-to-cell contacts for their differentiation and function. We generated knockout mice in which the RB gene was excised specifically in osteoblasts using the cre-lox P system and found that osteoblasts from pRb knockout mice did not assemble adherens junction at their membranes. pRb depletion in wild type osteoblasts using RNAi also disrupted adherens junctions. Microarrays comparing pRb-expressing and pRb-deficient osteoblasts showed that pRb controls the expression of a number of cell adhesion genes, including cadherins. Furthermore, pRb knockout mice showed bone abnormalities consistent with osteoblast adhesion defects. We also found that pRb controls the function of merlin, a well-known regulator of adherens junction assembly, by repressing Rac1 and its effector Pak1. Using qRT-PCR, immunoblots, co-immunoprecipitation assays, and immunofluorescent labeling, we observed that pRb loss resulted in Rac1 and Pak1 overexpression concomitant with merlin inactivation by Pak1, merlin detachment from the membrane, and adherens junction loss. Our data support a pRb function in cell adhesion while elucidating the mechanism for this function. Our work suggests that in some tumor types pRb inactivation results in both a loss of cell cycle control that promotes initial tumor growth as well as in a loss of cell-to-cell contacts, which contributes to later stages of metastasis. PMID:21085651

  2. Metabolic regulation of neutrophil spreading, membrane tubulovesicular extensions (cytonemes) formation and intracellular pH upon adhesion to fibronectin

    SciTech Connect

    Galkina, Svetlana I. . E-mail: galkina@genebee.msu.su; Sud'ina, Galina F.; Klein, Thomas

    2006-08-01

    Circulating leukocytes have a round cell shape and roll along vessel walls. However, metabolic disorders can lead them to adhere to the endothelium and spread (flatten). We studied the metabolic regulation of adhesion, spreading and intracellular pH (pHi) of neutrophils (polymorphonuclear leukocytes) upon adhesion to fibronectin-coated substrata. Resting neutrophils adhered and spread on fibronectin. An increase in pHi accompanied neutrophil spreading. Inhibition of oxidative phosphorylation or inhibition of P- and F-type ATPases affected neither neutrophil spreading nor pHi. Inhibition of glucose metabolism or V-ATPase impaired neutrophil spreading, blocked the increase in the pHi and induced extrusion of membrane tubulovesicular extensions (cytonemes), anchoring cells to substrata. Omission of extracellular Na{sup +} and inhibition of chloride channels caused a similar effect. We propose that these tubulovesicular extensions represent protrusions of exocytotic trafficking, supplying the plasma membrane of neutrophils with ion exchange mechanisms and additional membrane for spreading. Glucose metabolism and V-type ATPase could affect fusion of exocytotic trafficking with the plasma membrane, thus controlling neutrophil adhesive state and pHi. Cl{sup -} efflux through chloride channels and Na{sup +} influx seem to be involved in the regulation of the V-ATPase by carrying out charge compensation for the proton-pumping activity and through V-ATPase in regulation of neutrophil spreading and pHi.

  3. [Abdominal CSF pseudocyst recurrence in a 14-year-old patient with ventricular-peritoneal shunt].

    PubMed

    Laurent, P; Hennecker, J-L; Schillaci, A; Scordidis, V

    2014-08-01

    , the distal catheter is replaced in the abdominal cavity or in the atrium, the pleural space or the gallbladder if there is no suitable place for repositioning. If the peritoneal state allows it, a laparoscopic procedure is recommended to avoid peritoneal adhesion formation increasing the recurrence rate of CSF pseudocyst. PMID:24997061

  4. Focal adhesions in osteoneogenesis

    PubMed Central

    Biggs, M.J.P; Dalby, M.J

    2010-01-01

    As materials technology and the field of tissue engineering advances, the role of cellular adhesive mechanisms, in particular the interactions with implantable devices, becomes more relevant in both research and clinical practice. A key tenet of medical device technology is to use the exquisite ability of biological systems to respond to the material surface or chemical stimuli in order to help develop next-generation biomaterials. The focus of this review is on recent studies and developments concerning focal adhesion formation in osteoneogenesis, with an emphasis on the influence of synthetic constructs on integrin mediated cellular adhesion and function. PMID:21287830

  5. Abdominal aortic aneurysm

    MedlinePlus

    ... to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ... blood pressure Male gender Genetic factors An abdominal aortic aneurysm is most often seen in males over age ...

  6. Abdominal x-ray

    MedlinePlus

    ... More Abdominal aortic aneurysm Abdominal pain Acute cholecystitis Acute kidney failure Addison disease Adenomyosis Annular pancreas Aplastic anemia Appendicitis Ascariasis Atheroembolic renal disease Biliary atresia Blind loop syndrome Cholangitis Chronic ...

  7. The use of biomaterials in the repair of abdominal wall defects: a comparative study between polypropylene meshes (Marlex) and a new polytetrafluoroethylene prosthesis (Dual Mesh).

    PubMed

    Bellón, J M; Contreras, L A; Buján, J; Carrera-San Martín, A

    1997-10-01

    In this study we compared the behaviour of the non-porous on one side ePTFE Dual Mesh prosthesis and the macroporous polypropylene mesh Marlex in the repair of abdominal wall defects in rabbits. We evaluated the degree of integration with recipient tissue, biological tolerance, adhesion formation with viscera and the biomechanical resistance of the repair zone. Our results showed good biological tolerance of both prostheses and a high degree of adhesion formation in Marlex implants. In animals with Dual Mesh implants, only loose adhesions were seen. Marlex implants induced the presence of disorganized scar tissue, while the Dual Mesh prostheses were encapsulated by organized tissue. The macrophage response was similar in both decreasing with time. The resistance to traction was higher when the reparation was done with polypropylene. We concluded that the structure of the prosthesis determines its degree of integration and the resistance to traction of the repaired zone. PMID:9399138

  8. Intra-Abdominal Abscess and Primary Peritonitis Caused by Streptococcus anginosus

    PubMed Central

    Terzi, Huseyin Agah; Demiray, Tayfur; Koroglu, Mehmet; Cakmak, Guner; Hakki Ciftci, Ihsan; Ozbek, Ahmet; Altindis, Mustafa

    2016-01-01

    Introduction The Streptococcus anginosus group of bacteria are low-virulence bacteria existing as commensals in the oral flora and gastrointestinal tracts of humans. S. anginosus may spread to the blood in individuals with poor oral hygiene in cases of oral infections, such as gingivitis and tooth abscesses, that develop following the loss of mucosal unity. This may lead to infections in the whole body, primarily as brain and liver abscesses. Case Presentation A 32-year-old male patient presented with complaints of nausea, vomiting, and diffuse abdominal pain. Diffuse abdominal tenderness and rebound tenderness were detected particularly in the epigastrium and right upper quadrant. Laboratory assessment revealed a leukocyte count of 20,500/mm3. Free fluid around the liver and heterogeneous areas of abscess formation in the right lateral gallbladder were revealed on abdominal computed tomography. Diffuse adhesions between the bowel and seropurulent free liquid in the abdomen were detected on surgical exploration, and a sample was taken for cultures. The patient was discharged without complications on the sixth postoperative day and his antibiotic course was completed with 4 weeks of oral treatment. We reviewed the literature for similar cases of disseminated pyogenic infections caused by the S. anginosus group. Conclusions It should be kept in mind that the oral flora bacterium S. anginosus may cause transient bacteremia and deep-seated organ abscesses in immunodeficient patients with poor oral hygiene. Such patients with intra-abdominal abscesses should be treated with antibiotics and surgery.

  9. Small bowel obstruction and abdominal pain after robotic versus open radical prostatectomy.

    PubMed

    Lundström, Karl-Johan; Folkvaljon, Yasin; Loeb, Stacy; Axelson, Anna Bill; Stattin, Pär; Nordin, Pär

    2016-06-01

    Objective The aim of this study was to examine whether intraperitoneal robot-assisted surgery leads to small bowel obstruction (SBO), possibly caused by the formation of intra-abdominal adhesions. Materials and methods In total, 7256 men treated by intraperitoneal robot-assisted radical prostatectomy (RARP) and 9787 men treated by retropubic radical prostatectomy (RRP) in 2005-2012 were identified in the Prostate Cancer data Base Sweden (PCBaSe). Multivariable Cox proportional hazards models were used to calculate the risk of readmission for SBO, SBO-related surgery and admissions due to abdominal pain up to 5 years postoperatively. Results During the first postoperative year, the risk of readmission for SBO was higher after RARP than after RRP [hazard ratio (HR) 1.92, 95% confidence interval (CI) 1.14-3.25] but after 5 years there was no significant difference (HR 1.28, 95% CI 0.86-1.91), and there was no difference in the risk of SBO surgery during any period. The risk of admission for abdominal pain was significantly increased after RARP during the first year (HR 2.24, 95% CI 1.50-3.33) but not after 5 years (HR 1.23, 95% CI 0.92-1.63). Conclusion Intraperitoneal RARP had an increased risk of SBO and abdominal pain in the short term during the first year, but not in the long term, compared to RRP. PMID:26936203

  10. Abdominal Compartment Hypertension and Abdominal Compartment Syndrome.

    PubMed

    Maluso, Patrick; Olson, Jody; Sarani, Babak

    2016-04-01

    Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare but potentially morbid diagnoses. Clinical index of suspicion for these disorders should be raised following massive resuscitation, abdominal wall reconstruction/injury, and in those with space-occupying disorders in the abdomen. Gold standard for diagnosis involves measurement of bladder pressure, with a pressure greater than 12 mm Hg being consistent with IAH and greater than 25 mm Hg being consistent with ACS. Decompressive laparotomy is definitive therapy but paracentesis can be equally therapeutic in properly selected patients. Left untreated, ACS can lead to multisystem organ failure and death. PMID:27016163

  11. Synaptopodin-2 induces assembly of peripheral actin bundles and immature focal adhesions to promote lamellipodia formation and prostate cancer cell migration.

    PubMed

    Kai, FuiBoon; Fawcett, James P; Duncan, Roy

    2015-05-10

    Synaptopodin-2 (Synpo2), an actin-binding protein and invasive cancer biomarker, induces formation of complex stress fiber networks in the cell body and promotes PC3 prostate cancer cell migration in response to serum stimulation. The role of these actin networks in enhanced cancer cell migration is unknown. Using time-course analysis and live cell imaging of mock- and Synpo2-transduced PC3 cells, we now show that Synpo2 induces assembly of actin fibers near the cell periphery and Arp2/3-dependent lamellipodia formation. Lamellipodia formed in a non-directional manner or repeatedly changed direction, explaining the enhanced chemokinetic activity of PC3 cells in response to serum stimulation. Myosin contraction promotes retrograde flow of the Synpo2-associated actin filaments at the leading edge and their merger with actin networks in the cell body. Enhanced PC3 cell migration correlates with Synpo2-induced formation of lamellipodia and immature focal adhesions (FAs), but is not dependent on myosin contraction or FA maturation. The previously reported correlation between Synpo2-induced stress fiber assembly and enhanced PC3 cell migration therefore reflects the role of Synpo2 as a newly identified regulator of actin bundle formation and nascent FA assembly near the leading cell edge. PMID:25883213

  12. Abdominal Circulatory Interactions.

    PubMed

    Dagar, Gaurav; Taneja, Amit; Nanchal, Rahul S

    2016-04-01

    The abdominal compartment is separated from the thoracic compartment by the diaphragm. Under normal circumstances, a large portion of the venous return crosses the splanchnic and nonsplanchnic abdominal regions before entering the thorax and the right side of the heart. Mechanical ventilation may affect abdominal venous return independent of its interactions at the thoracic level. Changes in pressure in the intra-abdominal compartment may have important implications for organ function within the thorax, particularly if there is a sustained rise in intra-abdominal pressure. It is important to understand the consequences of abdominal pressure changes on respiratory and circulatory physiology. This article elucidates important abdominal-respiratory-circulatory interactions and their clinical effects. PMID:27016167

  13. 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.

  14. Sns and Kirre, the Drosophila orthologs of Nephrin and Neph1, direct adhesion, fusion and formation of a slit diaphragm-like structure in insect nephrocytes.

    PubMed

    Zhuang, Shufei; Shao, Huanjie; Guo, Fengli; Trimble, Rhonda; Pearce, Elspeth; Abmayr, Susan M

    2009-07-01

    The Immunoglobulin superfamily (IgSF) proteins Neph1 and Nephrin are co-expressed within podocytes in the kidney glomerulus, where they localize to the slit diaphragm (SD) and contribute to filtration between blood and urine. Herein, we demonstrate that their Drosophila orthologs Kirre (Duf) and Sns are co-expressed within binucleate garland cell nephrocytes (GCNs) that contribute to detoxification of the insect hemolymph by uptake of molecules through an SD-like nephrocyte diaphragm (ND) into labyrinthine channels that are active sites of endocytosis. The functions of Kirre and Sns in the embryonic musculature, to mediate adhesion and fusion between myoblasts to form multinucleate muscle fibers, have been conserved in the GCNs, where they contribute to adhesion of GCNs in the ;garland' and to their fusion into binucleate cells. Sns and Kirre proteins localize to the ND at the entry point into the labyrinthine channels and, like their vertebrate counterparts, are essential for its formation. Knockdown of Kirre or Sns drastically reduces the number of NDs at the cell surface. These defects are associated with a decrease in uptake of large proteins, suggesting that the ND distinguishes molecules of different sizes and controls access to the channels. Moreover, mutations in the Sns fibronectin-binding or immunoglobulin domains lead to morphologically abnormal NDs and to reduced passage of proteins into the labyrinthine channels for uptake by endocytosis, suggesting a crucial and direct role for Sns in ND formation and function. These data reveal significant similarities between the insect ND and the SD in mammalian podocytes at the level of structure and function. PMID:19515699

  15. Traumatic pseudoaneurysm of the abdominal aorta.

    PubMed

    Barchiche, R; Bové, T; Demanet, H; Goldstein, J P; Deuvaert, F E

    1999-08-01

    A traumatic pseudoaneurysm of the abdominal aorta is a rare entity, occurring as the result of a missed aortic lesion at the time of the initial injury. Therefore, clinical suspicion and careful abdominal exploration at first laparotomy is mandatory to prevent aortic pseudoaneurysm formation and its risk of delayed rupture. We present a case of successful surgical treatment of a suprarenal aortic false aneurysm, presenting 4 weeks after a life-threatening gunshot wound in a 13-year-old child. PMID:10499389

  16. Early Postoperative Pain After Keyless Abdominal Rope-Lifting Surgery

    PubMed Central

    Hüseyınoğlu, Ürfettin; Çıçek, Melek

    2015-01-01

    Background and Objectives: Keyless abdominal rope-lifting surgery is a novel, gasless, single-incision laparoscopic surgical technique. In this study we aimed to compare the postoperative pain from keyless abdominal rope-lifting surgery with carbon dioxide laparoscopy performed for benign ovarian cysts. Methods: During a 20-month period, 77 women underwent surgery for a benign ovarian cyst. Keyless abdominal rope-lifting surgery and conventional carbon dioxide laparoscopy techniques were used for the operations in 32 women and 45 women, respectively. The 2 operative techniques were compared with regard to demographic characteristics; preoperative, intraoperative, and postoperative data including early postoperative pain scores; and frequency of shoulder pain and analgesic requirements. Results: Data regarding demographic characteristics, preoperative findings, cyst diameters and rupture rates, intra-abdominal adhesions, intraoperative blood loss, and postoperative hospital stay did not differ between groups (P > .05). However, the mean operative and abdominal access times were significantly longer in the keyless abdominal rope-lifting surgery group (P < .05). Visual analog scale pain scores at initially and at the second, fourth, and 24th hours of the postoperative period were significantly lower in the keyless abdominal rope-lifting surgery group (P < .05). Similarly, keyless abdominal rope-lifting surgery caused significantly less shoulder pain and additional analgesic use (P < .05). Conclusion: Keyless abdominal rope-lifting surgery seems to cause less pain in the management of benign ovarian cysts in comparison with conventional carbon dioxide laparoscopy. PMID:25848177

  17. Abdominal CT scan

    MedlinePlus

    ... tumors, including cancer Infections or injury Kidney stones Appendicitis ... also be due to: Abdominal aortic aneurysm Abscesses Appendicitis Bowel wall thickening Retroperitoneal fibrosis Renal artery stenosis ...

  18. Design of high-performance anti-adhesion agent using injectable gel with an anti-oxidative stress function.

    PubMed

    Nakagawa, Hiroyuki; Matsumoto, Yoko; Matsumoto, Yu; Miwa, Yoshihiro; Nagasaki, Yukio

    2015-11-01

    Postsurgical tissue adhesion formation caused by inflammation and oxidative stress is one of the serious issues because it induces severe clinical disorders. In this study, we designed redox injectable gel (RIG) which covalently possesses nitroxide radicals as a reactive oxygen species (ROS) scavenger for high performance anti-adhesion agent. The redox flower micelles exhibiting gelation under physiological conditions were prepared by a polyion complex (PIC) between polyamine-PEG-polyamine triblock copolymer possessing nitroxide radicals as a side chain of polyamine segments and poly(acrylic acid). RIG showed prolonged local retention in the abdominal cavity of the mice, which was monitored by in vivo imaging system (IVIS). Compared with a commercial anti-adhesion agent (Seprafilm(®), Genzyme, Cambridge, MA), RIG dramatically inhibited the formation of tissue adhesions via a combination of physical separation and biological elimination of generated ROS in talc-induced adhesion model mice. Treatment with RIG suppressed inflammatory cytokines and neutrophil invasion, suppressing the increase in peritoneal membrane thickness. It is also emphasized that RIG suppressed the increase of white blood cells level, indicating that the present RIG treatment effectively prevents diffusion of local inflammation to entire body. These findings indicate that RIG has a great potential as a high performance anti-adhesion agent. PMID:26288251

  19. Filamentation and spatiotemporal distribution of extracellular polymeric substances: role on X.fastidiosa single cell adhesion and biofilm formation (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Janissen, Richard; Murillo, Duber M.; Niza, Barbara; Sahoo, Prasana K.; Monteiro, Moniellen P.; César, Carlos L.; Carvalho, Hernandes F.; de Souza, Alessandra A.; Cotta, Monica A.

    2016-04-01

    Biofilms can be defined as a community of microorganisms attached to a surface, living embedded in a self- produced matrix of hydrated extracellular polymeric substances (EPS) which comprises most of the biofilm mass. We have recently used an extensive pool of microscopy techniques (confocal fluorescence, electron and scanning probe microscopies) at the micro and nanoscales in order to create a detailed temporal observation of Xylella fastidiosa biofilm formation, using both wild type strain and Green Fluorescent Protein (GFP)-modified cells of this citrus phytopathogen. We have identified three different EPS compositions, as well as their spatial and temporal distribution from single cell to mature biofilm formation stages. In the initial adhesion stage, soluble-EPS (S-EPS) accumulates at cell polar regions and forms a surface layer which facilitates irreversible cell attachment and cell cluster formation. These small clusters are subsequently connected by filamentous cells; further S-EPS surface coverage facilitates cell attachment and form filaments, leading to a floating framework of mature biofilms. The important role of EPS in X.fastidiosa biology was further investigated by imunolabelling experiments to detect the distribution of XadA1 adhesin, which is expressed in early stages of biofilm formation and released in outer membrane vesicles. This protein is located mainly in S-EPS covered areas, as well as on the filaments, indicating a molecular pathway to the enhanced cell attachment previously observed. These results suggest that S-EPS may thus represent an important target for disease control, slow plant colonization by the bacteria, keeping the plant more productive in the field.

  20. Abdominal aortic aneurysm.

    PubMed

    Keisler, Brian; Carter, Chuck

    2015-04-15

    Abdominal aortic aneurysm refers to abdominal aortic dilation of 3.0 cm or greater. The main risk factors are age older than 65 years, male sex, and smoking history. Other risk factors include a family history of abdominal aortic aneurysm, coronary artery disease, hypertension, peripheral artery disease, and previous myocardial infarction. Diagnosis may be made by physical examination, an incidental finding on imaging, or ultrasonography. The U.S. Preventive Services Task Force released updated recommendations for abdominal aortic aneurysm screening in 2014. Men 65 to 75 years of age with a history of smoking should undergo one-time screening with ultrasonography based on evidence that screening will improve abdominal aortic aneurysm-related mortality in this population. Men in this age group without a history of smoking may benefit if they have other risk factors (e.g., family history of abdominal aortic aneurysm, other vascular aneurysms, coronary artery disease). There is inconclusive evidence to recommend screening for abdominal aortic aneurysm in women 65 to 75 years of age with a smoking history. Women without a smoking history should not undergo screening because the harms likely outweigh the benefits. Persons who have a stable abdominal aortic aneurysm should undergo regular surveillance or operative intervention depending on aneurysm size. Surgical intervention by open or endovascular repair is the primary option and is typically reserved for aneurysms 5.5 cm in diameter or greater. There are limited options for medical treatment beyond risk factor modification. Ruptured abdominal aortic aneurysm is a medical emergency presenting with hypotension, shooting abdominal or back pain, and a pulsatile abdominal mass. It is associated with high prehospitalization mortality. Emergent surgical intervention is indicated for a rupture but has a high operative mortality rate. PMID:25884861

  1. Adhesion, Biofilm Formation, and Genomic Features of Campylobacter jejuni Bf, an Atypical Strain Able to Grow under Aerobic Conditions.

    PubMed

    Bronnec, Vicky; Turoňová, Hana; Bouju, Agnès; Cruveiller, Stéphane; Rodrigues, Ramila; Demnerova, Katerina; Tresse, Odile; Haddad, Nabila; Zagorec, Monique

    2016-01-01

    Campylobacter jejuni is the leading cause of bacterial enteritis in Europe. Human campylobacteriosis cases are frequently associated to the consumption of contaminated poultry meat. To survive under environmental conditions encountered along the food chain, i.e., from poultry digestive tract its natural reservoir to the consumer's plate, this pathogen has developed adaptation mechanisms. Among those, biofilm lifestyle has been suggested as a strategy to survive in the food environment and under atmospheric conditions. Recently, the clinical isolate C. jejuni Bf has been shown to survive and grow under aerobic conditions, a property that may help this strain to better survive along the food chain. The aim of this study was to evaluate the adhesion capacity of C. jejuni Bf and its ability to develop a biofilm. C. jejuni Bf can adhere to abiotic surfaces and to human epithelial cells, and can develop biofilm under both microaerobiosis and aerobiosis. These two conditions have no influence on this strain, unlike results obtained with the reference strain C. jejuni 81-176, which harbors only planktonic cells under aerobic conditions. Compared to 81-176, the biofilm of C. jejuni Bf is more homogenous and cell motility at the bottom of biofilm was not modified whatever the atmosphere used. C. jejuni Bf whole genome sequence did not reveal any gene unique to this strain, suggesting that its unusual property does not result from acquisition of new genetic material. Nevertheless some genetic particularities seem to be shared only between Bf and few others strains. Among the main features of C. jejuni Bf genome we noticed (i) a complete type VI secretion system important in pathogenicity and environmental adaptation; (ii) a mutation in the oorD gene involved in oxygen metabolism; and (iii) the presence of an uncommon insertion of a 72 amino acid coding sequence upstream from dnaK, which is involved in stress resistance. Therefore, the atypical behavior of this strain under

  2. Adhesion, Biofilm Formation, and Genomic Features of Campylobacter jejuni Bf, an Atypical Strain Able to Grow under Aerobic Conditions

    PubMed Central

    Bronnec, Vicky; Turoňová, Hana; Bouju, Agnès; Cruveiller, Stéphane; Rodrigues, Ramila; Demnerova, Katerina; Tresse, Odile; Haddad, Nabila; Zagorec, Monique

    2016-01-01

    Campylobacter jejuni is the leading cause of bacterial enteritis in Europe. Human campylobacteriosis cases are frequently associated to the consumption of contaminated poultry meat. To survive under environmental conditions encountered along the food chain, i.e., from poultry digestive tract its natural reservoir to the consumer’s plate, this pathogen has developed adaptation mechanisms. Among those, biofilm lifestyle has been suggested as a strategy to survive in the food environment and under atmospheric conditions. Recently, the clinical isolate C. jejuni Bf has been shown to survive and grow under aerobic conditions, a property that may help this strain to better survive along the food chain. The aim of this study was to evaluate the adhesion capacity of C. jejuni Bf and its ability to develop a biofilm. C. jejuni Bf can adhere to abiotic surfaces and to human epithelial cells, and can develop biofilm under both microaerobiosis and aerobiosis. These two conditions have no influence on this strain, unlike results obtained with the reference strain C. jejuni 81-176, which harbors only planktonic cells under aerobic conditions. Compared to 81-176, the biofilm of C. jejuni Bf is more homogenous and cell motility at the bottom of biofilm was not modified whatever the atmosphere used. C. jejuni Bf whole genome sequence did not reveal any gene unique to this strain, suggesting that its unusual property does not result from acquisition of new genetic material. Nevertheless some genetic particularities seem to be shared only between Bf and few others strains. Among the main features of C. jejuni Bf genome we noticed (i) a complete type VI secretion system important in pathogenicity and environmental adaptation; (ii) a mutation in the oorD gene involved in oxygen metabolism; and (iii) the presence of an uncommon insertion of a 72 amino acid coding sequence upstream from dnaK, which is involved in stress resistance. Therefore, the atypical behavior of this strain under

  3. Large bowel obstruction secondary to adhesive bands.

    PubMed

    El-Masry, Nabil S; Geevarghese, Ruben

    2015-01-01

    Large bowel obstruction (LBO) is most commonly due to malignancy, volvulus, hernia, diverticular disease and inflammatory bowel disease. LBO due to adhesions is unusual. A literature review was conducted which revealed that only a few such cases have been reported. We report two cases of LBO secondary to adhesions in patients, one with and one without a past abdominal surgical history. We highlight that while rare, the aetiology of LBO secondary to adhesions must be considered in the differential diagnosis in patients presenting with obstructive symptoms. PMID:25650387

  4. [Abdominal pregnancy, institutional experience].

    PubMed

    Bonfante Ramírez, E; Bolaños Ancona, R; Simón Pereyra, L; Juárez García, L; García-Benitez, C Q

    1998-07-01

    Abdominal pregnancy is a rare entity, which has been classified as primary or secondary by Studiford criteria. A retrospective study, between January 1989 and December 1994, realized at Instituto Nacional de Perinatología, found 35,080 pregnancies, from which 149 happened to be ectopic, and 6 of them were abdominal. All patients belonged to a low income society class, age between 24 and 35 years, and average of gestations in 2.6. Gestational age varied from 15 weeks to 32.2 weeks having only one delivery at term with satisfactory postnatal evolution. One patient had a recurrent abdominal pregnancy, with genital Tb as a conditional factor. Time of hospitalization varied from 4 to 5 days, and no further patient complications were reported. Fetal loss was estimated in 83.4%. Abdominal pregnancy is often the sequence of a tubarian ectopic pregnancy an when present, it has a very high maternal mortality reported in world literature, not found in this study. The stated frequency of abdominal pregnancy is from 1 of each 3372, up to 1 in every 10,200 deliveries, reporting in the study 1 abdominal pregnancy in 5846 deliveries. The study had two characteristic entities one, the recurrence and two, the delivery at term of one newborn. Abdominal pregnancy accounts for 4% of all ectopic pregnancies. Clinical findings in abdominal pregnancies are pain, transvaginal bleeding and amenorrea, being the cardinal signs of ectopic pregnancy. PMID:9737070

  5. Recurrent Abdominal Pain

    ERIC Educational Resources Information Center

    Banez, Gerard A.; Gallagher, Heather M.

    2006-01-01

    The purpose of this article is to provide an empirically informed but clinically oriented overview of behavioral treatment of recurrent abdominal pain. The epidemiology and scope of recurrent abdominal pain are presented. Referral process and procedures are discussed, and standardized approaches to assessment are summarized. Treatment protocols…

  6. Adhesive small bowel adhesions obstruction: Evolutions in diagnosis, management and prevention

    PubMed Central

    Catena, Fausto; Di Saverio, Salomone; Coccolini, Federico; Ansaloni, Luca; De Simone, Belinda; Sartelli, Massimo; Van Goor, Harry

    2016-01-01

    Intra-abdominal adhesions following abdominal surgery represent a major unsolved problem. They are the first cause of small bowel obstruction. Diagnosis is based on clinical evaluation, water-soluble contrast follow-through and computed tomography scan. For patients presenting no signs of strangulation, peritonitis or severe intestinal impairment there is good evidence to support non-operative management. Open surgery is the preferred method for the surgical treatment of adhesive small bowel obstruction, in case of suspected strangulation or after failed conservative management, but laparoscopy is gaining widespread acceptance especially in selected group of patients. "Good" surgical technique and anti-adhesive barriers are the main current concepts of adhesion prevention. We discuss current knowledge in modern diagnosis and evolving strategies for management and prevention that are leading to stratified care for patients. PMID:27022449

  7. New and Simple Approach for Preventing Postoperative Peritoneal Adhesions: Do not Touch the Peritoneum without Viscous Liquid—A Multivariate Analysis

    PubMed Central

    Aysan, Erhan; Bektas, Hasan; Ersoz, Feyzullah; Sari, Serkan; Kaygusuz, Arslan; Huq, Gulben Erdem

    2012-01-01

    Background. Postoperative peritoneal adhesions (PPAs) are an unsolved and serious problem in abdominal surgery. Method. Viscous liquids of soybean oil, octyl methoxycinnamate, flax oil, aloe vera gel, and glycerol were used in five experiments, using the same methodology for each. Liquids were applied in the peritoneal cavity before and after mechanical peritoneal trauma. Results were evaluated by multivariate analysis. Results. Compared with the control group, macroscopic and microscopic adhesion values before (P < .001) and after (P < .05) application of viscous liquids significantly reduced PPAs. Values were significantly lower when liquids were applied before rather than after peritoneal trauma (P < .0001). Discussion. Viscous liquids injected into the peritoneal cavity before or after mechanical peritoneal trauma decrease PPA. Injection before trauma was more effective than after trauma. In surgical practice, PPA formation may be prevented or decreased by covering the peritoneal cavity with an appropriate viscous liquid before abdominal surgery. PMID:22363347

  8. EFFECTS OF TOPICAL TREATMENT WITH EUPHORBIA TIRUCALLI LATEX ON THE SURVIVAL AND INTESTINAL ADHESIONS IN RATS WITH EXPERIMENTAL PERITONITIS

    PubMed Central

    de ARAÚJO, Lilhian Alves; MRUÉ, Fátima; NEVES, Roberpaulo Anacleto; ALVES, Maxley Martins; da SILVA-JÚNIOR, Nelson Jorge; SILVA, Marcelo Seixo de Brito; de MELO-REIS, Paulo Roberto

    2015-01-01

    Background: The use of plants of the family Euphorbiaceae, particularly Euphorbia tirucalli (avelós) has been popularly widespread for treating a variety of diseases of infectious, tumoral, and inflammatory. Aim: To demonstrated antimicrobial and immunomodulatory effects of these extracts, evaluating the effect of a topical treatment with an aqueous solution of avelós latex on the survival and on intestinal adhesions in rats with experimental peritonitis. Methods: Peritonitis was induced in 24 Wistar rats, that were randomized into four groups of six as follows: (1) Control group (n=6), no treatment; (2) Antibiotic group (n=6), treatment with a single intramuscular dose of antibiotic Unasyn; (3) Saline group (n=6), the abdominal cavity was washed with 0.9% saline; and (4) E.tirucalli group (n=6), the abdominal cavity was washed with E. tirucalli at a concentration of 12 mg/ml. The animals that died were necropsied, and the time of death was recorded. The survivors were killed on postoperative day 11, and necropsy was subsequently performed for evaluation of the intestinal adhesions. Results: Significant differences were observed in the control and antibiotic groups (p<0.01) with respect to the survival hours when compared with the saline and E. tirucalli groups. There was no significant difference (p>0.05) in the survival of animals in the saline andE. tirucalli groups; however, one animal died in the saline group. Necropsy of the animals in the saline and E. tirucalligroups showed strong adhesions resistant to manipulation, between the intestinal loops and abdominal wall. The remaining groups did not show any adhesions. Conclusions: Topical treatment with E. tirucalli latex stimulated an increased formation of intestinal adhesions and prevented the death of all animals with peritonitis. PMID:26734792

  9. Qualitative SEM/EDS analysis of microleakage and apical gap formation of adhesive root-filling materials

    PubMed Central

    SOUZA, Soraia de Fátima Carvalho; FRANCCI, Carlos; BOMBANA, Antonio C.; KENSHIMA, Silvia; BARROSO, Lúcia P.; D'AGOSTINO, Liz Z.; LOGUERCIO, Alessandro D.

    2012-01-01

    Objective The aim of this study was to compare the correspondence between gap formation and apical microleakage in root canals filled with epoxy resin-based (AH Plus) combined or not with resinous primer or with a dimethacrylate-based root canal sealer (Epiphany). Material and Methods Thirty-nine lower single-rooted human premolars were filled by the lateral condensation technique (LC) and immersed in a 50-wt% aqueous silver nitrate solution at 37ºC (24 h). After longitudinal sectioning, epoxy resin replicas were made from the tooth specimens. Both the replicas and the specimens were prepared for scanning electron microscopy (SEM). The gaps were observed in the replicas. Apical microleakage was detected in the specimens by SEM/energy dispersive spectroscopy (SEM/EDS). The data were analyzed statistically using an Ordinal Logistic Regression model and Analysis of Correspondence (α=0.05). Results Epiphany presented more regions containing gaps between dentin and sealer (p<0.05). There was correspondence between the presence of gaps and microleakage (p<0.05). Microleakage was similar among the root-filling materials (p>0.05). Conclusions The resinous primer did not improve the sealing ability of AH Plus sealer and the presence of gaps had an effect on apical microleakage for all materials. PMID:22858699

  10. Bond formation and slow heterogeneous dynamics in adhesive spheres with long-ranged repulsion: quantitative test of mode coupling theory.

    PubMed

    Henrich, O; Puertas, A M; Sperl, M; Baschnagel, J; Fuchs, M

    2007-09-01

    A colloidal system of spheres interacting with both a deep and narrow attractive potential and a shallow long-ranged barrier exhibits a prepeak in the static structure factor. This peak can be related to an additional mesoscopic length scale of clusters and/or voids in the system. Simulation studies of this system have revealed that it vitrifies upon increasing the attraction into a gel-like solid at intermediate densities. The dynamics at the mesoscopic length scale corresponding to the prepeak represents the slowest mode in the system. Using mode coupling theory with all input directly taken from simulations, we reveal the mechanism for glassy arrest in the system at 40% packing fraction. The effects of the low-q peak and of polydispersity are considered in detail. We demonstrate that the local formation of physical bonds is the process whose slowing down causes arrest. It remains largely unaffected by the large-scale heterogeneities, and sets the clock for the slow cluster mode. Results from mode-coupling theory without adjustable parameters agree semiquantitatively with the local density correlators but overestimate the lifetime of the mesoscopic structure (voids). PMID:17930244

  11. The Aspergillus fumigatus sitA Phosphatase Homologue Is Important for Adhesion, Cell Wall Integrity, Biofilm Formation, and Virulence

    PubMed Central

    Bom, Vinícius Leite Pedro; de Castro, Patrícia Alves; Winkelströter, Lizziane K.; Marine, Marçal; Hori, Juliana I.; Ramalho, Leandra Naira Zambelli; dos Reis, Thaila Fernanda; Goldman, Maria Helena S.; Brown, Neil Andrew; Rajendran, Ranjith; Ramage, Gordon; Walker, Louise A.; Munro, Carol A.; Rocha, Marina Campos; Malavazi, Iran; Hagiwara, Daisuke

    2015-01-01

    Aspergillus fumigatus is an opportunistic pathogenic fungus able to infect immunocompromised patients, eventually causing disseminated infections that are difficult to control and lead to high mortality rates. It is important to understand how the signaling pathways that regulate these factors involved in virulence are orchestrated. Protein phosphatases are central to numerous signal transduction pathways. Here, we characterize the A. fumigatus protein phosphatase 2A SitA, the Saccharomyces cerevisiae Sit4p homologue. The sitA gene is not an essential gene, and we were able to construct an A. fumigatus null mutant. The ΔsitA strain had decreased MpkA phosphorylation levels, was more sensitive to cell wall-damaging agents, had increased β-(1,3)-glucan and chitin, was impaired in biofilm formation, and had decreased protein kinase C activity. The ΔsitA strain is more sensitive to several metals and ions, such as MnCl2, CaCl2, and LiCl, but it is more resistant to ZnSO4. The ΔsitA strain was avirulent in a murine model of invasive pulmonary aspergillosis and induces an augmented tumor necrosis factor alpha (TNF-α) response in mouse macrophages. These results stress the importance of A. fumigatus SitA as a possible modulator of PkcA/MpkA activity and its involvement in the cell wall integrity pathway. PMID:25911225

  12. Neural cell adhesion molecule 2 promotes the formation of filopodia and neurite branching by inducing submembrane increases in Ca2+ levels.

    PubMed

    Sheng, Lifu; Leshchyns'ka, Iryna; Sytnyk, Vladimir

    2015-01-28

    Changes in expression of the neural cell adhesion molecule 2 (NCAM2) have been proposed to contribute to neurodevelopmental disorders in humans. The role of NCAM2 in neuronal differentiation remains, however, poorly understood. Using genetically encoded Ca(2+) reporters, we show that clustering of NCAM2 at the cell surface of mouse cortical neurons induces submembrane [Ca(2+)] spikes, which depend on the L-type voltage-dependent Ca(2+) channels (VDCCs) and require activation of the protein tyrosine kinase c-Src. We also demonstrate that clustering of NCAM2 induces L-type VDCC- and c-Src-dependent activation of CaMKII. NCAM2-dependent submembrane [Ca(2+)] spikes colocalize with the bases of filopodia. NCAM2 activation increases the density of filopodia along neurites and neurite branching and outgrowth in an L-type VDCC-, c-Src-, and CaMKII-dependent manner. Our results therefore indicate that NCAM2 promotes the formation of filopodia and neurite branching by inducing Ca(2+) influx and CaMKII activation. Changes in NCAM2 expression in Down syndrome and autistic patients may therefore contribute to abnormal neurite branching observed in these disorders. PMID:25632147

  13. 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.' PMID:27186047

  14. Polyimide adhesives

    NASA Technical Reports Server (NTRS)

    Progar, D. J.; Bell, V. L.; Saintclair, T. L. (Inventor)

    1974-01-01

    A process of preparing aromatic polyamide-acids for use as adhesives is described. An equimolar quantity of an aromatic dianhydride is added to a stirred solution of an aromatic diamine in a water or alcohol-miscible ether solvent to obtain a viscous polymer solution. The polymeric-acid intermediate polymer does not become insoluble but directly forms a smooth viscous polymer solution. These polyamic-acid polymers are converted, by heating in the range of 200-300 C and with pressure, to form polyimides with excellent adhesive properties.

  15. Abdominal ultrasound (image)

    MedlinePlus

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X- ... use high frequency sound waves to produce an image and do not expose the individual to radiation. ...

  16. Abdominal ultrasound (image)

    MedlinePlus

    Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X-ray, MRI, ... it has its place as a diagnostic tool. Ultrasound scans use high frequency sound waves to produce ...

  17. Abdominal exploration - series (image)

    MedlinePlus

    ... surgical exploration of the abdomen, also called an exploratory laparotomy, may be recommended when there is abdominal ... blunt trauma"). Diseases that may be discovered by exploratory laparotomy include: inflammation of the appendix (acute appendicitis) ...

  18. Abdominal aortic aneurysm

    MedlinePlus

    ... main blood vessel that supplies blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs ... dissection). Symptoms of rupture include: Pain in the abdomen or back. The pain may be severe, sudden, ...

  19. Abdominal x-ray

    MedlinePlus

    An abdominal x-ray is an imaging test to look at organs and structures in the abdomen. Organs include the spleen, stomach, and intestines. When the test is done to look at the bladder and kidney structures, ...

  20. Abdominal aortic aneurysm.

    PubMed

    Setacci, Francesco; Galzerano, Giuseppe; De Donato, Gianmarco; Benevento, Domenico; Guerrieri, Massimiliano W; Ruzzi, Umberto; Borrelli, Maria P; Setacci, Carlo

    2016-02-01

    Endovascular repair of abdominal aortic aneurysms has become a milestone in the treatment of patients with abdominal aortic aneurysm. Technological improvement allows treatment in more and more complex cases. This review summarizes all grafts available on the market. A complete review of most important trial on this topic is provided to the best of our knowledge, and technical tips and tricks for standard cases are also included. PMID:26771730

  1. 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.

  2. Wear mechanism based on adhesion

    NASA Technical Reports Server (NTRS)

    Yamamoto, T.; Buckley, D. H.

    1982-01-01

    Various concepts concerning wear mechanisms and deformation behavior observed in the sliding wear track are surveyed. The mechanisms for wear fragment formation is discussed on the basis of adhesion. The wear process under unlubricated sliding conditions is explained in relation to the concept of adhesion at the interface during the sliding process. The mechanism for tearing away the surface layer from the contact area and forming the sliding track contour is explained by assuming the simplified process of material removal based on the adhesion theory.

  3. Suitable in vitro Eimeria arloingi macromeront formation in host endothelial cells and modulation of adhesion molecule, cytokine and chemokine gene transcription.

    PubMed

    Silva, Liliana M R; Vila-Viçosa, Maria J M; Cortes, Helder C E; Taubert, Anja; Hermosilla, Carlos

    2015-01-01

    Eimeria arloingi infections can cause severe haemorrhagic enteritis in young goat kids, thereby leading to high economic losses in goat industry worldwide. We aimed to isolate a new E. arloingi strain and establish a suitable in vitro culture system for the first merogony. E. arloingi oocysts were collected from naturally infected goat kids in the province of Alentejo, Portugal. For the maintenance of E. arloingi (strain A), kids kept under strict parasite-free conditions were orally infected with 10(3) sporulated oocysts each. Further, a new excystation protocol was successfully established to obtain viable sporozoites for further in vitro development in primary bovine umbilical vein endothelial cells (BUVEC). Overall, E. arloingi first merogony was successfully accomplished in BUVEC leading to macromeront formation (up to 150 μm) and the release of fully developed merozoites I stages. Moreover, host endothelial cell-parasite interactions were investigated in order to determine the extent of modulation carried out by E. arloingi in BUVEC during the first merogony. Gene transcription of adhesion molecules (E-selectin, P-selectin, VCAM-1, ICAM-1) was enhanced in the first hours post-infection (p.i.) in E. arloingi-infected BUVEC. BUVEC activation due to invasion was also shown by increased chemokine (CXCL8, CCL2, CCL5), cytokine (GM-CSF) and COX-2 gene transcription. The new E. arloingi (strain A) will be useful for better comprehension of early host innate immune reactions against this parasite in vitro/in vivo as well as to further our investigations in the complex Eimeria-host endothelial cell interactions. PMID:25339511

  4. Adhesion- and Degranulation-Promoting Adapter Protein Promotes CD8 T Cell Differentiation and Resident Memory Formation and Function during an Acute Infection.

    PubMed

    Fiege, Jessica K; Beura, Lalit K; Burbach, Brandon J; Shimizu, Yoji

    2016-09-15

    During acute infections, naive Ag-specific CD8 T cells are activated and differentiate into effector T cells, most of which undergo contraction after pathogen clearance. A small population of CD8 T cells persists as memory to protect against future infections. We investigated the role of adhesion- and degranulation-promoting adapter protein (ADAP) in promoting CD8 T cell responses to a systemic infection. Naive Ag-specific CD8 T cells lacking ADAP exhibited a modest expansion defect early after Listeria monocytogenes or vesicular stomatitis virus infection but comparable cytolytic function at the peak of response. However, reduced numbers of ADAP-deficient CD8 T cells were present in the spleen after the peak of the response. ADAP deficiency resulted in a greater frequency of CD127(+) CD8 memory precursors in secondary lymphoid organs during the contraction phase. Reduced numbers of ADAP-deficient killer cell lectin-like receptor G1(-) CD8 resident memory T (TRM) cell precursors were present in a variety of nonlymphoid tissues at the peak of the immune response, and consequently the total numbers of ADAP-deficient TRM cells were reduced at memory time points. TRM cells that did form in the absence of ADAP were defective in effector molecule expression. ADAP-deficient TRM cells exhibited impaired effector function after Ag rechallenge, correlating with defects in their ability to form T cell-APC conjugates. However, ADAP-deficient TRM cells responded to TGF-β signals and recruited circulating memory CD8 T cells. Thus, ADAP regulates CD8 T cell differentiation events following acute pathogen challenge that are critical for the formation and selected functions of TRM cells in nonlymphoid tissues. PMID:27521337

  5. [PROPHYLAXIS OF AN ACUTE ADHESIVE ILEUS RECURRENCE].

    PubMed

    Evtushenko, D A

    2015-10-01

    The results of treatment of 56 patients were studied, in whom for adhesive abdominal disease, complicated by an acute adhesive ileus (AAI), the adhesiolysis with intraabdominal introduction of antiadhesive measures, named Mezogel, Defensal were conducted, as well as in 42 patients, operated on in emergency for AAI, using a routine method. Application of videolaparoscopy gives a possibility to control the adhesive process in the early postoperative period, what is necessary for prophylaxis of the adhesive disease occurence. Application of the apparatus, we have elaborated, permitted to conduct a precisional viscerolysis due to good visualization of organs, pathologically changed and healthy tissues. Application of the procedures elaborated for prophylaxis of the AAI recurrence have promoted the reduction of risk for the AAI occurence down to 1.8%, and of disorders of the gut contents transit in terms up to 1 yr - to 3.6%. PMID:26946653

  6. Abdominal Fat Is Associated With Lower Bone Formation and Inferior Bone Quality in Healthy Premenopausal Women: A Transiliac Bone Biopsy Study

    PubMed Central

    Dempster, David W.; Recker, Robert R.; Lappe, Joan M.; Zhou, Hua; Zwahlen, Alexander; Müller, Ralph; Zhao, Binsheng; Guo, Xiaotao; Lang, Thomas; Saeed, Isra; Liu, X. Sherry; Guo, X. Edward; Cremers, Serge; Rosen, Clifford J.; Stein, Emily M.; Nickolas, Thomas L.; McMahon, Donald J.; Young, Polly; Shane, Elizabeth

    2013-01-01

    Context: The conventional view that obesity is beneficial for bone strength has recently been challenged by studies that link obesity, particularly visceral obesity, to low bone mass and fractures. It is controversial whether effects of obesity on bone are mediated by increased bone resorption or decreased bone formation. Objective: The objective of the study was to evaluate bone microarchitecture and remodeling in healthy premenopausal women of varying weights. Design: We measured bone density and trunk fat by dual-energy x-ray absorptiometry in 40 women and by computed tomography in a subset. Bone microarchitecture, stiffness, remodeling, and marrow fat were assessed in labeled transiliac bone biopsies. Results: Body mass index (BMI) ranged from 20.1 to 39.2 kg/m2. Dual-energy x-ray absorptiometry-trunk fat was directly associated with BMI (r = 0.78, P < .001) and visceral fat by computed tomography (r = 0.79, P < .001). Compared with women in the lowest tertile of trunk fat, those in the highest tertile had inferior bone quality: lower trabecular bone volume (20.4 ± 5.8 vs 29.1 ± 6.1%; P = .001) and stiffness (433 ± 264 vs 782 ± 349 MPa; P = .01) and higher cortical porosity (8.8 ± 3.5 vs 6.3 ± 2.4%; P = .049). Bone formation rate (0.004 ± 0.002 vs 0.011 ± 0.008 mm2/mm · year; P = .006) was 64% lower in the highest tertile. Trunk fat was inversely associated with trabecular bone volume (r = −0.50; P < .01) and bone formation rate (r = −0.50; P < .001). The relationship between trunk fat and bone volume remained significant after controlling for age and BMI. Conclusions: At the tissue level, premenopausal women with more central adiposity had inferior bone quality and stiffness and markedly lower bone formation. Given the rising levels of obesity, these observations require further investigation. PMID:23515452

  7. Abdominal Dual Energy Imaging

    NASA Astrophysics Data System (ADS)

    Sommer, F. Graham; Brody, William R.; Cassel, Douglas M.; Macovski, Albert

    1981-11-01

    Dual energy scanned projection radiography of the abdomen has been performed using an experimental line-scanned radiographic system. Digital images simultaneously obtained at 85 and 135 kVp are combined, using photoelectric/Compton decomposition algorithms to create images from which selected materials are cancelled. Soft tissue cancellation images have proved most useful in various abdominal imaging applications, largely due to the elimination of obscuring high-contrast bowel gas shadows. These techniques have been successfully applied to intravenous pyelography, oral cholecystography, intravenous abdominal arteriog-raphy and the imaging of renal calculi.

  8. The Acute Abdominal Aorta.

    PubMed

    Mellnick, Vincent M; Heiken, Jay P

    2015-11-01

    Acute disorders of the abdominal aorta are potentially lethal conditions that require prompt evaluation and treatment. Computed tomography (CT) is the primary imaging method for evaluating these conditions because of its availability and speed. Volumetric CT acquisition with multiplanar reconstruction and three-dimensional analysis is now the standard technique for evaluating the aorta. MR imaging may be useful for select applications in stable patients in whom rupture has been excluded. Imaging is indispensable for diagnosis and treatment planning, because management has shifted toward endoluminal repair. Acute abdominal aortic conditions most commonly are complications of aneurysms and atherosclerosis. PMID:26526434

  9. Abdominal Vascular Catastrophes.

    PubMed

    Singh, Manpreet; Koyfman, Alex; Martinez, Joseph P

    2016-05-01

    Abdominal vascular catastrophes are among the most challenging and time sensitive for emergency practitioners to recognize. Mesenteric ischemia remains a highly lethal entity for which the history and physical examination can be misleading. Laboratory tests are often unhelpful, and appropriate imaging must be quickly obtained. A multidisciplinary approach is required to have a positive impact on mortality rates. Ruptured abdominal aortic aneurysm likewise may present in a cryptic fashion. A specific type of ruptured aneurysm, the aortoenteric fistula, often masquerades as the more common routine gastrointestinal bleed. The astute clinician recognizes that this is a more lethal variant of gastrointestinal hemorrhage. PMID:27133247

  10. Abdominal Aortic Aneurysms

    PubMed Central

    Fortner, George; Johansen, Kaj

    1984-01-01

    Aneurysms are common in our increasingly elderly population, and are a major threat to life and limb. Until the advent of vascular reconstructive techniques, aneurysm patients were subject to an overwhelming risk of death from exsanguination. The first successful repair of an abdominal aortic aneurysm using an interposed arterial homograft was reported by Dubost in 1952. A milestone in the evolution of vascular surgery, this event and subsequent diagnostic, operative and prosthetic graft refinements have permitted patients with an unruptured abdominal aortic aneurysm to enjoy a better prognosis than patients with almost any other form of major systemic illness. Images PMID:6702193

  11. ATP release due to Thy-1–integrin binding induces P2X7-mediated calcium entry required for focal adhesion formation

    PubMed Central

    Henríquez, Mauricio; Herrera-Molina, Rodrigo; Valdivia, Alejandra; Alvarez, Alvaro; Kong, Milene; Muñoz, Nicolás; Eisner, Verónica; Jaimovich, Enrique; Schneider, Pascal; Quest, Andrew F. G.; Leyton, Lisette

    2011-01-01

    Thy-1, an abundant mammalian glycoprotein, interacts with αvβ3 integrin and syndecan-4 in astrocytes and thus triggers signaling events that involve RhoA and its effector p160ROCK, thereby increasing astrocyte adhesion to the extracellular matrix. The signaling cascade includes calcium-dependent activation of protein kinase Cα upstream of Rho; however, what causes the intracellular calcium transients required to promote adhesion remains unclear. Purinergic P2X7 receptors are important for astrocyte function and form large non-selective cation pores upon binding to their ligand, ATP. Thus, we evaluated whether the intracellular calcium required for Thy-1-induced cell adhesion stems from influx mediated by ATP-activated P2X7 receptors. Results show that adhesion induced by the fusion protein Thy-1-Fc was preceded by both ATP release and sustained intracellular calcium elevation. Elimination of extracellular ATP with Apyrase, chelation of extracellular calcium with EGTA, or inhibition of P2X7 with oxidized ATP, all individually blocked intracellular calcium increase and Thy-1-stimulated adhesion. Moreover, Thy-1 mutated in the integrin-binding site did not trigger ATP release, and silencing of P2X7 with specific siRNA blocked Thy-1-induced adhesion. This study is the first to demonstrate a functional link between αvβ3 integrin and P2X7 receptors, and to reveal an important, hitherto unanticipated, role for P2X7 in calcium-dependent signaling required for Thy-1-stimulated astrocyte adhesion. PMID:21502139

  12. 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.

  13. Abdominal Pain, Long-Term

    MedlinePlus

    MENU Return to Web version Abdominal Pain, Long-term See complete list of charts. Ongoing or recurrent abdominal pain, also called chronic pain, may be difficult to diagnose, causing frustration for ...

  14. Screening for Abdominal Aortic Aneurysm

    MedlinePlus

    Understanding Task Force Recommendations Screening for Abdominal Aortic Aneurysm The U.S. Preventive Services Task Force (Task Force) ... final recommendation statement on Screening for Abdominal Aortic Aneurysm. This final recommendation statement applies to adults ages ...

  15. Peritoneal adhesion index (PAI): proposal of a score for the "ignored iceberg" of medicine and surgery.

    PubMed

    Coccolini, Federico; Ansaloni, Luca; Manfredi, Roberto; Campanati, Luca; Poiasina, Elia; Bertoli, Paolo; Capponi, Michela Giulii; Sartelli, Massimo; Di Saverio, Salomone; Cucchi, Michele; Lazzareschi, Daniel; Pisano, Michele; Catena, Fausto

    2013-01-01

    Peritoneal adhesions describe a condition in which pathological bonds form between the omentum, the small and large bowels, the abdominal wall, and other intra-abdominal organs. Different classification systems have been proposed, but they do not resolve the underlying problem of ambiguity in the quantification and definition of adhesions. We therefore propose a standardized classification system of adhesions to universalize their definition based on the macroscopic appearance of adhesions and their diffusion to different regions of the abdomen. By scoring with these criteria, the peritoneal adhesion index (PAI) can range from 0 to 30, unambiguously specifying precise adhesion scenarios. The standardized classification and quantification of adhesions would enable different studies to more meaningfully integrate their results, thereby facilitating a more comprehensive approach to the treatment and management of this pathology. PMID:23369320

  16. Synaptic Cell Adhesion Molecules in Alzheimer's Disease

    PubMed Central

    Leshchyns'ka, Iryna

    2016-01-01

    Alzheimer's disease (AD) is a neurodegenerative brain disorder associated with the loss of synapses between neurons in the brain. Synaptic cell adhesion molecules are cell surface glycoproteins which are expressed at the synaptic plasma membranes of neurons. These proteins play key roles in formation and maintenance of synapses and regulation of synaptic plasticity. Genetic studies and biochemical analysis of the human brain tissue, cerebrospinal fluid, and sera from AD patients indicate that levels and function of synaptic cell adhesion molecules are affected in AD. Synaptic cell adhesion molecules interact with Aβ, a peptide accumulating in AD brains, which affects their expression and synaptic localization. Synaptic cell adhesion molecules also regulate the production of Aβ via interaction with the key enzymes involved in Aβ formation. Aβ-dependent changes in synaptic adhesion affect the function and integrity of synapses suggesting that alterations in synaptic adhesion play key roles in the disruption of neuronal networks in AD. PMID:27242933

  17. Critical factors affecting the 3D microstructural formation in hybrid conductive adhesive materials studied by X-ray nano-tomography

    NASA Astrophysics Data System (ADS)

    Chen-Wiegart, Yu-Chen Karen; Figueroa-Santos, Miriam Aileen; Petrash, Stanislas; Garcia-Miralles, Jose; Wang, Jun

    2014-12-01

    Conductive adhesives are found favorable in a wide range of applications including a lead-free solder in micro-chips, flexible and printable electronics and enhancing the performance of energy storage devices. Composite materials comprised of metallic fillers and a polymer matrix are of great interest to be implemented as hybrid conductive adhesives. Here we investigated a cost-effective conductive adhesive material consisting of silver-coated copper as micro-fillers using synchrotron-based three-dimensional (3D) X-ray nano-tomography. The key factors affecting the quality and performance of the material were quantitatively studied in 3D on the nanometer scale for the first time. A critical characteristic parameter, defined as a shape-factor, was determined to yield a high-quality silver coating, leading to satisfactory performance. A `stack-and-screen' mechanism was proposed to elaborate such a phenomenon. The findings and the technique developed in this work will facilitate the future advancement of conductive adhesives to have a great impact in micro-electronics and other applications.Conductive adhesives are found favorable in a wide range of applications including a lead-free solder in micro-chips, flexible and printable electronics and enhancing the performance of energy storage devices. Composite materials comprised of metallic fillers and a polymer matrix are of great interest to be implemented as hybrid conductive adhesives. Here we investigated a cost-effective conductive adhesive material consisting of silver-coated copper as micro-fillers using synchrotron-based three-dimensional (3D) X-ray nano-tomography. The key factors affecting the quality and performance of the material were quantitatively studied in 3D on the nanometer scale for the first time. A critical characteristic parameter, defined as a shape-factor, was determined to yield a high-quality silver coating, leading to satisfactory performance. A `stack-and-screen' mechanism was proposed to

  18. Adhesion Awareness: A National Survey of Surgeons

    PubMed Central

    Schreinemacher, Marc H. F.; ten Broek, Richard P.; Bakkum, Erica A.; van Goor, Harry

    2010-01-01

    Background Postoperative adhesions are the most frequent complication of abdominal surgery, leading to high morbidity, mortality, and costs. However, the problem seems to be neglected by surgeons for largely unknown reasons. Methods A survey assessing knowledge and personal opinion about the extent and impact of adhesions was sent to all Dutch surgeons and surgical trainees. The informed-consent process and application of antiadhesive agents were questioned in addition. Results The response rate was 34.4%. Two thirds of all respondents (67.7%) agreed that adhesions exert a clinically relevant, negative effect. A negative perception of adhesions correlated with a positive attitude regarding adhesion prevention (ρ = 0.182, p < 0.001). However, underestimation of the extent and impact of adhesions resulted in low knowledge scores (mean test score 37.6%). Lower scores correlated with more uncertainty about indications for antiadhesive agents which, in turn, correlated with never having used any of these agents (ρ = 0.140, p = 0.002; ρ = 0.095, p = 0.035; respectively). Four in 10 respondents (40.9%) indicated that they never inform patients on adhesions and only 9.8% informed patients routinely. A majority of surgeons (55.9%) used antiadhesive agents in the past, but only a minority (13.4%) did in the previous year. Of trainees, 82.1% foresaw an increase in the use of antiadhesive agents compared to 64.5% of surgeons (p < 0.001). Conclusions The magnitude of the problem of postoperative adhesions is underestimated and informed consent is provided inadequately by Dutch surgeons. Exerting adhesion prevention is related to the perception of and knowledge about adhesions. PMID:20814678

  19. Abdominal closure using nonabsorbable mesh after massive resuscitation prevents abdominal compartment syndrome and gastrointestinal fistula.

    PubMed

    Ciresi, D L; Cali, R F; Senagore, A J

    1999-08-01

    Patients who receive high-volume resuscitation after massive abdominopelvic trauma, or emergent repair of a ruptured abdominal aortic aneurysm (RAAA), are at a significant risk for postoperative abdominal compartment syndrome (ACS). Absorbable prosthetic closure of the abdominal wall has been recommended as a means of managing ACS. However, use of absorbable prosthetic has been associated with very high rates of intestinal fistula formation and ventral hernia formation. The purpose of this study was to retrospectively review our experience with the use of nonabsorbable prosthetic abdominal closures in patients with documented ACS or at high risk for ACS. All patients managed by this technique from July 1995 through July 1997 after repair of ruptured abdominal aortic aneurysm or massive abdominopelvic trauma were evaluated. A total of 18 patients were identified: 15 primary prosthetic placements (Gore-Tex patch, 12; Marlex mesh, 2; and silastic mesh, 1) and 3 delayed prosthetic placements for ACS (Gore-Tex, 1 and Marlex, 2). The mortality rate was 22 percent (4 of 18) and resulted from multisystem organ failure (2 patients), cardiac arrest 1 hour postoperatively (1 patient), and severe closed head injury (1 patient). Secondary closure and prosthetic removal was possible in 16 of 18 patients, including the 2 patients who died of multisystem organ failure within the same hospitalization. Delayed abdominal closure at a subsequent admission was performed in two cases. This same patient developed an enterocutaneous fistula 2 months after discharge. Importantly, only 1 of 18 closed in this manner developed ACS requiring reoperation. The results indicate that use of a nonabsorbable prosthetic, particularly with Gore-Tex, is efficacious in the prevention of postoperative ACS in high-risk patients, while it enhances the possibility for delayed abdominal closure and minimizes the risk of gastrointestinal fistulization associated with other techniques. PMID:10432080

  20. Entrapped ovarian cyst. An unusual case of persistent abdominal pain.

    PubMed

    Hederström, E; Forsberg, L

    1990-05-01

    Recurrent abdominal pain in the left fossa often mimicking attacks of subileus is described in a woman aged 48 with extensive adhesions caused by multiple surgical procedures. Repeated examinations with conventional abdominal radiography and barium meals were negative with regard to mechanical intestinal obstruction. A cystic lesion varying in size from 2 to 8 cm in diameter was seen adjacent to the left ovary on repeat US examinations and also on CT. Pain episodes were sometimes correlated to increasing size of the lesion which was finally thought to be either a peritoneal inclusion cyst (fluid trapped between pelvic adhesions) or, as was finally confirmed at surgery, a true ovarian cyst (corpus luteum cyst) similarly trapped. PMID:2201330

  1. Critical factors affecting the 3D microstructural formation in hybrid conductive adhesive materials studied by X-ray nano-tomography.

    PubMed

    Chen-Wiegart, Yu-chen Karen; Figueroa-Santos, Miriam Aileen; Petrash, Stanislas; Garcia-Miralles, Jose; Wang, Jun

    2015-01-21

    Conductive adhesives are found favorable in a wide range of applications including a lead-free solder in micro-chips, flexible and printable electronics and enhancing the performance of energy storage devices. Composite materials comprised of metallic fillers and a polymer matrix are of great interest to be implemented as hybrid conductive adhesives. Here we investigated a cost-effective conductive adhesive material consisting of silver-coated copper as micro-fillers using synchrotron-based three-dimensional (3D) X-ray nano-tomography. The key factors affecting the quality and performance of the material were quantitatively studied in 3D on the nanometer scale for the first time. A critical characteristic parameter, defined as a shape-factor, was determined to yield a high-quality silver coating, leading to satisfactory performance. A 'stack-and-screen' mechanism was proposed to elaborate such a phenomenon. The findings and the technique developed in this work will facilitate the future advancement of conductive adhesives to have a great impact in micro-electronics and other applications. PMID:25474162

  2. Adhesion of yeast cells to different porous supports, stability of cell-carrier systems and formation of volatile by-products.

    PubMed

    Kregiel, Dorota; Berlowska, Joanna; Ambroziak, Wojciech

    2012-12-01

    The aim of our research was to study how the conditions of immobilization influence cell attachment to two different ceramic surfaces: hydroxylapatite and chamotte tablets. Three fermentative yeast strains, namely brewery TT, B4 (ale, lager) and distillery Bc15a strains belonging to Saccharomyces spp., and one strain of Debaryomyces occidentalis Y500/5 of weak fermentative nature, but with high amylolytic activity due to extracellular α-amylase and glucoamylase, were used in this study. Different media, including cell starvation, were applied for immobilization of yeast strains as well as different phases of cell growth. Immobilization of selected yeasts on a hydroxylapatite carrier was rather weak. However, when incubation of starved yeast cells was conducted in the minimal medium supplemented by calcium carbonate, the scale of immobilization after 24 h was higher, especially for the D. occidentalis strain. Adhesion to hydroxylapatite carriers in wort broth was of reversible character and better results of adhesion were observed in the case of another ceramic carrier-chamotte. The number of immobilized cells was about 10(6)-10(7) per tablet and cell adhesion was stable during the whole fermentation process. The comparison of the volatile products that were formed during fermentation did not show any significant qualitative and quantitative differences between the free and the immobilized cells. This is the first time when a cheap, porous chamotte surface has been applied to yeast adhesion and fermentation processes. PMID:22903785

  3. Nucleation and growth of cadherin adhesions

    SciTech Connect

    Lambert, Mireille; Thoumine, Olivier; Brevier, Julien; Choquet, Daniel; Riveline, Daniel; Mege, Rene-Marc

    2007-11-15

    Cell-cell contact formation relies on the recruitment of cadherin molecules and their anchoring to actin. However, the precise chronology of events from initial cadherin trans-interactions to adhesion strengthening is unclear, in part due to the lack of access to the distribution of cadherins within adhesion zones. Using N-cadherin expressing cells interacting with N-cadherin coated surfaces, we characterized the formation of cadherin adhesions at the ventral cell surface. TIRF and RIC microscopies revealed streak-like accumulations of cadherin along actin fibers. FRAP analysis indicated that engaged cadherins display a slow turnover at equilibrium, compatible with a continuous addition and removal of cadherin molecules within the adhesive contact. Association of cadherin cytoplasmic tail to actin as well as actin cables and myosin II activity are required for the formation and maintenance of cadherin adhesions. Using time lapse microscopy we deciphered how cadherin adhesions form and grow. As lamellipodia protrude, cadherin foci stochastically formed a few microns away from the cell margin. Neo-formed foci coalesced aligned and coalesced with preformed foci either by rearward sliding or gap filling to form cadherin adhesions. Foci experienced collapse at the rear of cadherin adhesions. Based on these results, we present a model for the nucleation, directional growth and shrinkage of cadherin adhesions.

  4. Component separation in abdominal trauma.

    PubMed

    Rawstorne, Edward; Smart, Christopher J; Fallis, Simon A; Suggett, Nigel

    2014-01-01

    Component separation is established for complex hernia repairs. This case presents early component separation and release of the anterior and posterior sheath to facilitate closure of the abdominal wall following emergency laparotomy, reinforcing the repair with a biological mesh. On Day 11 following an emergency laparotomy for penetrating trauma, this patient underwent component separation and release of the anterior and posterior sheath. An intra-abdominal biological mesh was secured, and the fascia and skin closed successfully. Primary abdominal closure can be achieved in patients with penetrating abdominal trauma with the use of component separation and insertion of intra-abdominal biological mesh, where standard closure is not possible. PMID:24876334

  5. 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.

  6. 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.

  7. In Vitro Colonization of the Muscle Extracellular Matrix Components by Escherichia coli O157:H7: The Influence of Growth Medium, Temperature and pH on Initial Adhesion and Induction of Biofilm Formation by Collagens I and III

    PubMed Central

    Chagnot, Caroline; Agus, Allison; Renier, Sandra; Peyrin, Frédéric; Talon, Régine; Astruc, Thierry; Desvaux, Mickaël

    2013-01-01

    Enterohemorrhagic Escherichia coli (EHEC) O157:H7 are responsible for repeated food-poisoning cases often caused by contaminated burgers. EHEC infection is predominantly a pediatric illness, which can lead to life-threatening diseases. Ruminants are the main natural reservoir for EHEC and food contamination almost always originates from faecal contamination. In beef meat products, primary bacterial contamination occurs at the dehiding stage of slaughtering. The extracellular matrix (ECM) is the most exposed part of the skeletal muscles in beef carcasses. Investigating the adhesion to the main muscle fibrous ECM proteins, insoluble fibronectin, collagen I, III and IV, laminin-α2 and elastin, results demonstrated that the preceding growth conditions had a great influence on subsequent bacterial attachment. In the tested experimental conditions, maximal adhesion to fibril-forming collagens I or III occurred at 25°C and pH 7. Once initially adhered, exposure to lower temperatures, as applied to meat during cutting and storage, or acidification, as in the course of post-mortem physiological modifications of muscle, had no effect on detachment, except at pHu. In addition, dense biofilm formation occurred on immobilized collagen I or III and was induced in growth medium supplemented with collagen I in solution. From this first comprehensive investigation of EHEC adhesion to ECM proteins with respect to muscle biology and meat processing, new research directions for the development of innovative practices to minimize the risk of meat contamination are further discussed. PMID:23516631

  8. In vitro colonization of the muscle extracellular matrix components by Escherichia coli O157:H7: the influence of growth medium, temperature and pH on initial adhesion and induction of biofilm formation by collagens I and III.

    PubMed

    Chagnot, Caroline; Agus, Allison; Renier, Sandra; Peyrin, Frédéric; Talon, Régine; Astruc, Thierry; Desvaux, Mickaël

    2013-01-01

    Enterohemorrhagic Escherichia coli (EHEC) O157:H7 are responsible for repeated food-poisoning cases often caused by contaminated burgers. EHEC infection is predominantly a pediatric illness, which can lead to life-threatening diseases. Ruminants are the main natural reservoir for EHEC and food contamination almost always originates from faecal contamination. In beef meat products, primary bacterial contamination occurs at the dehiding stage of slaughtering. The extracellular matrix (ECM) is the most exposed part of the skeletal muscles in beef carcasses. Investigating the adhesion to the main muscle fibrous ECM proteins, insoluble fibronectin, collagen I, III and IV, laminin-α2 and elastin, results demonstrated that the preceding growth conditions had a great influence on subsequent bacterial attachment. In the tested experimental conditions, maximal adhesion to fibril-forming collagens I or III occurred at 25°C and pH 7. Once initially adhered, exposure to lower temperatures, as applied to meat during cutting and storage, or acidification, as in the course of post-mortem physiological modifications of muscle, had no effect on detachment, except at pHu. In addition, dense biofilm formation occurred on immobilized collagen I or III and was induced in growth medium supplemented with collagen I in solution. From this first comprehensive investigation of EHEC adhesion to ECM proteins with respect to muscle biology and meat processing, new research directions for the development of innovative practices to minimize the risk of meat contamination are further discussed. PMID:23516631

  9. Abdominal trauma by ostrich

    PubMed Central

    Usurelu, Sergiu; Bettencourt, Vanessa; Melo, Gina

    2015-01-01

    Introduction Ostriches typically avoid humans in the wild, since they correctly assess humans as potential predators, and, if approached, often run away. However, ostriches may turn aggressive rather than run when threatened, especially when cornered, and may also attack when they feel the need to defend their offspring or territories. Presentation of case A 71-year-old male patient presented with intra abdominal injury sustained from being kicked in the abdominal wall by an ostrich. During laparotomy, were found free peritoneal effusion and perforation of the small intestine. Discussion The clinical history and physical examination are extremely important for diagnostic and therapeutic decision making. CT-scan is the most accurate exam for making diagnosis. Surgery is the treatment of choice, and is always indicated when there is injury to the hollow viscera. In general it is possible to suture the defect. Conclusion In cases of blunt abdominal trauma by animals is necessary to have a low threshold of suspicion for acute abdomen. PMID:25685344

  10. Hypothesis: Role for the circadian Clock system and sleep in the pathogenesis of adhesions and chronic pelvic pain?

    PubMed

    Sadek, Khaled; Macklon, Nick; Bruce, Kim; Cagampang, Felino; Cheong, Ying

    2011-03-01

    Intra-peritoneal adhesions ensuing from surgery or infection may lead to chronic pelvic pain, bowel obstruction, infertility and additional invasive surgery to resolve adhesion-related complications. As a result adhesions are a major clinical, social and economic concern. The cumulative year-on-year direct costs of adhesion-related readmissions for a 10-year period are more than £ 569 million. The degree of intra-abdominal adhesion formation in an individual patient after a surgical or infective insult remains difficult to predict. This reflects a lack of understanding as to the underlying aetiologies. Several different mechanisms leading to adhesion formation and re-formation have been proposed. These include abnormal modulations in inflammatory status, fibrinolytic pathways and matrix remodelling. A number of preventative strategies have been designed accordingly. However, although each individual model offers specific insights into the aetiology of adhesion formation, none have been shown to provide the basis for a highly effective clinical intervention. A unifying fundamental mechanism remains elusive. In this article we propose that such a mechanism can be found within the molecular control of circadian rhythms and "Clock" gene biology. A number of physiological processes demonstrating circadian variation have been shown to involve 'Clock genes' in the suprachiasmatic nucleus (SCN), which then entrains a similar set of Clock genes in peripheral tissues such as the heart, brain, spleen, lung, liver, skeletal muscle and kidney. The intrinsic time-keeping system influences activity, such as sleep, temperature regulation, rates of metabolism, immune responses, blood pressure and hormone secretion. The function and availability of mediators involved in the inflammatory response, fibrinolytic and anti-coagulation pathways are all under the tight control of the molecular Clock system. These include IL-6, PAI-1, fibrinogen, fibroblasts and TNF-α. We hypothesise that

  11. Enzymatic formation of a novel cell-adhesive hydrogel based on small peptides with a laterally grafted l-3,4-dihydroxyphenylalanine group

    NASA Astrophysics Data System (ADS)

    Xu, J. X.; Zhou, Z.; Wu, B.; He, B. F.

    2014-01-01

    We rationally designed a bioadhesive supramolecular hydrogel by introducing l-3,4-dihydroxylphenylalanine (DOPA) groups while properly integrating the enzymatic reactions and self-assembly processes. The effective presence of the catechol groups successfully promoted the adhesion and proliferation of human fibroblast cells.We rationally designed a bioadhesive supramolecular hydrogel by introducing l-3,4-dihydroxylphenylalanine (DOPA) groups while properly integrating the enzymatic reactions and self-assembly processes. The effective presence of the catechol groups successfully promoted the adhesion and proliferation of human fibroblast cells. Electronic supplementary information (ESI) available: Detailed experimental procedures, synthesis and characterization of the compounds and hydrogel preparation. See DOI: 10.1039/c3nr04528e

  12. Ankyrin repeat domain 28 (ANKRD28), a novel binding partner of DOCK180, promotes cell migration by regulating focal adhesion formation.

    PubMed

    Tachibana, Mitsuhiro; Kiyokawa, Etsuko; Hara, Shigeo; Iemura, Shun-Ichiro; Natsume, Tohru; Manabe, Toshiaki; Matsuda, Michiyuki

    2009-03-10

    DOCK180 is a guanine exchange factor of Rac1 originally identified as a protein bound to an SH3 domain of the Crk adaptor protein. DOCK180 induces tyrosine phosphorylation of p130(Cas), and recruits the Crk-p130(Cas) complex to focal adhesions. To understand the role of DOCK180 in cell adhesion and migration, we searched for DOCK180-binding proteins with a nano-LC/MS/MS system, and identified ANKRD28, a protein that contains twenty-six ankyrin domain repeats. Knockdown of ANKRD28 by RNA interference reduced the velocity of migration of HeLa cells, suggesting that this protein plays a physiologic role in the DOCK180-Rac1 signaling pathway. Furthermore, knockdown of ANKRD28 was found to alter the distribution of focal adhesion proteins such as Crk, paxillin, and p130(Cas). On the other hand, expression of ANKRD28, p130(Cas), Crk, and DOCK180 induced hyper-phosphorylation of p130(Cas), and impaired detachment of the cell membrane during migration. Consequently, cells expressing ANKRD28 exhibited multiple long cellular processes. ANKRD28 associated with DOCK180 in an SH3-dependent manner and competed with ELMO, another protein bound to the SH3 domain of DOCK180. In striking contrast to ANKRD28, overexpression of ELMO induced extensive lamellipodial protrusion around the entire circumference. These data suggest that ANKRD28 specifies the localization and the activity of the DOCK180-Rac1 pathway. PMID:19118547

  13. Laparoscopic Management of Adhesive Small Bowel Obstruction

    PubMed Central

    Konjic, Ferid; Idrizovic, Enes; Hasukic, Ismar; Jahic, Alen

    2016-01-01

    Introduction: Adhesions are the reason for bowel obstruction in 80% of the cases. In well selected patients the adhesive ileus laparoscopic treatment has multiple advantages which include the shorter hospitalization period, earlier food taking, and less postoperative morbidity rate. Case report: Here we have a patient in the age of 35 hospitalized at the clinic due to occlusive symptoms. Two years before an opened appendectomy had been performed on him. He underwent the treatment of exploration laparoscopy and laparoscopic adhesiolysis. Dilated small bowel loops connected with the anterior abdominal wall in the ileocecal region by adhesions were found intraoperatively and then resected harmonically with scalpel. One strangulation around which a small bowel loop was wrapped around was found and dissected. Postoperative course was normal. PMID:27041815

  14. Adhesion as a weapon in microbial competition

    PubMed Central

    Schluter, Jonas; Nadell, Carey D; Bassler, Bonnie L; Foster, Kevin R

    2015-01-01

    Microbes attach to surfaces and form dense communities known as biofilms, which are central to how microbes live and influence humans. The key defining feature of biofilms is adhesion, whereby cells attach to one another and to surfaces, via attachment factors and extracellular polymers. While adhesion is known to be important for the initial stages of biofilm formation, its function within biofilm communities has not been studied. Here we utilise an individual-based model of microbial groups to study the evolution of adhesion. While adhering to a surface can enable cells to remain in a biofilm, consideration of within-biofilm competition reveals a potential cost to adhesion: immobility. Highly adhesive cells that are resistant to movement face being buried and starved at the base of the biofilm. However, we find that when growth occurs at the base of a biofilm, adhesion allows cells to capture substratum territory and force less adhesive, competing cells out of the system. This process may be particularly important when cells grow on a host epithelial surface. We test the predictions of our model using the enteric pathogen Vibrio cholerae, which produces an extracellular matrix important for biofilm formation. Flow cell experiments indicate that matrix-secreting cells are highly adhesive and form expanding clusters that remove non-secreting cells from the population, as predicted by our simulations. Our study shows how simple physical properties, such as adhesion, can be critical to understanding evolution and competition within microbial communities. PMID:25290505

  15. Behaviour of a New Composite Mesh for the Repair of Full-Thickness Abdominal Wall Defects in a Rabbit Model

    PubMed Central

    Pascual, Gemma; Sotomayor, Sandra; Rodríguez, Marta; Bayon, Yves; Bellón, Juan M.

    2013-01-01

    Introduction Composite biomaterials designed for the repair of abdominal wall defects are composed of a mesh component and a laminar barrier in contact with the visceral peritoneum. This study assesses the behaviour of a new composite mesh by comparing it with two latest-generation composites currently used in clinical practice. Methods Defects (7x5cm) created in the anterior abdominal wall of New Zealand White rabbits were repaired using a polypropylene mesh and the composites: PhysiomeshTM; VentralightTM and a new composite mesh with a three-dimensional macroporous polyester structure and an oxidized collagen/chitosan barrier. Animals were sacrificed on days 14 and 90 postimplant. Specimens were processed to determine host tissue incorporation, gene/protein expression of neo-collagens (RT-PCR/immunofluorescence), macrophage response (RAM-11-immunolabelling) and biomechanical resistance. On postoperative days 7/14, each animal was examined laparoscopically to quantify adhesions between the visceral peritoneum and implant. Results The new composite mesh showed the lowest incidence of seroma in the short term. At each time point, the mesh surface covered with adhesions was greater in controls than composites. By day 14, the implants were fully infiltrated by a loose connective tissue that became denser over time. At 90 days, the peritoneal mesh surface was lined with a stable mesothelium. The new composite mesh induced more rapid tissue maturation than PhysiomeshTM, giving rise to a neoformed tissue containing more type I collagen. In VentralightTM the macrophage reaction was intense and significantly greater than the other composites at both follow-up times. Tensile strengths were similar for each biomaterial. Conclusions All composites showed optimal peritoneal behaviour, inducing good peritoneal regeneration and scarce postoperative adhesion formation. A greater foreign body reaction was observed for VentralightTM. All composites induced good collagen deposition

  16. [Differential diagnosis of abdominal pain].

    PubMed

    Frei, Pascal

    2015-09-01

    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. PMID:26331201

  17. Abdominal imaging: An introduction

    SciTech Connect

    Frick, M.P.; Feinberg, S.B.

    1986-01-01

    This nine-chapter book gives an overview of the integrated approach to abdominal imaging. Chapter 1 provides an introduction to the physics used in medical imaging; chapter 2 is on the selection of imaging modalities. These are followed by four chapters that deal, respectively, with plain radiography, computed tomographic scanning, sonography, and nuclear imaging, as applied to the abdomen. Two chapters then cover contrast material-enhanced studies of the gastrointestinal (GI) tract: one focusing on technical considerations; the other, on radiologic study of disease processes. The final chapter is a brief account of different interventional procedures.

  18. Lower Abdominal Pain.

    PubMed

    Carlberg, David J; Lee, Stephen D; Dubin, Jeffrey S

    2016-05-01

    Although most frequently presenting with lower abdominal pain, appendicitis, colitis, and diverticulitis can cause pain throughout the abdomen and can cause peritoneal and retroperitoneal symptoms. Evaluation and management of lower intestinal disease requires a nuanced approach by the emergency physician, sometimes requiring computed tomography, ultrasonography, MRI, layered imaging, shared decision making, serial examination, and/or close follow-up. Once a presumed or confirmed diagnosis is made, appropriate treatment is initiated, and may include surgery, antibiotics, and/or steroids. Appendicitis patients should be admitted. Diverticulitis and inflammatory bowel disease can frequently be managed on an outpatient basis, but may require admission and surgical consultation. PMID:27133242

  19. Hypnosis for functional abdominal pain.

    PubMed

    Gottsegen, David

    2011-07-01

    Chronic abdominal pain is a common pediatric condition affecting 20% of the pediatric population worldwide. Most children with this disorder are found to have no specific organic etiology and are given the diagnosis of functional abdominal pain. Well-designed clinical trials have found hypnotherapy and guided imagery to be the most efficacious treatments for this condition. Hypnotic techniques used for other somatic symptoms are easily adaptable for use with functional abdominal pain. The author discusses 2 contrasting hypnotic approaches to functional abdominal pain and provides implications for further research. These approaches may provide new insights into this common and complex disorder. PMID:21922712

  20. 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.

  1. Use of N,O-carboxymethyl chitosan to prevent postsurgical adhesions in a rabbit double uterine horn model: a randomized controlled design.

    PubMed

    Ren, Chang; Zhao, Dachun; Zhu, Lan

    2016-05-01

    In previous studies, N,O-carboxymethyl chitosan has been shown to decrease the incidence and intensity of abdominal adhesions. In the present study, adhesions were induced in 220 rabbits using a double uterine horn model. Rabbits were randomized to receive an operation only or an operation+medical chitosan intraperitoneally. Twenty-two rabbits from each group were euthanized at one of five different times (Day 3, 7, 14, 28, or 42), and adhesion formation was given gross and histopathological scores. Reductions were observed in adhesion extent (P=0.0337) and tenacity (P=0.0271) as well as inflammation (P<0.0001) on Day 3 when medical chitosan was applied. Prior to Day 14, fibrosis was less obvious in the medical chitosan group (P< 0.0005). The tenacity scores were significantly lower in the medical chitosan group following Day 14 (P<.05), while the type scores were lower in the medical chitosan group following Day 28 (P<.03). Thus, medical chitosan decreased both the gross and the histopathological scores of the induced adhesions. PMID:26842129

  2. How I Manage Abdominal Injuries.

    ERIC Educational Resources Information Center

    Haycock, Christine E.

    1986-01-01

    In sports, abdominal injuries occur most frequently in cycling, horseback riding, and skiing. Most involve children, not adults. Any athlete sustaining a severe blow to the abdomen should be examined. Guidelines are provided for recognizing and treating injuries to the abdominal muscles, kidneys, spleen, and liver. (Author/MT)

  3. Functional Abdominal Pain in Children

    MedlinePlus

    ... dominalPa in inCh ildre n What is functional abdominal pain, and why does it happen? Most otherwise-healthy ... stomachaches for two months or more have functional abdominal pain. The term “functional” refers to the fact that ...

  4. Understanding Marine Mussel Adhesion

    SciTech Connect

    H. G. Silverman; F. F. Roberto

    2007-12-01

    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 waterimpervious 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.

  5. Understanding marine mussel adhesion.

    PubMed

    Silverman, Heather G; 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

  6. 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

  7. Abdominal migraine in the differential diagnosis of acute abdominal pain.

    PubMed

    Cervellin, Gianfranco; Lippi, Giuseppe

    2015-06-01

    Although traditionally regarded as a specific pediatric disease, abdominal migraine may also be observed in adults. Unfortunately, however, this condition is frequently overlooked in the differential diagnosis of abdominal pain in the emergency department (ED). A 30-year-old woman presented to our ED complaining of abdominal pain and vomiting, lasting for 12 hours. The pain was periumbilical, continuous, and not associated with fever or diarrhea. The physical examination and the results of conventional blood tests were normal. The patient was treated with intravenous ketoprofen, metoclopramide, and ranitidine, obtaining a prompt relief of symptoms. She had a history of similar episodes in the last 15 years, with several ED visits, blood test examinations, ultrasonography of the abdomen, and upper gastrointestinal endoscopies. Celiac disease, porphyry, sickle cell disease, and inflammatory bowel disease were all excluded. In July 2012, she became pregnant, and she delivered a healthy baby on April 2013. Until November 2014, she has remained asymptomatic. Based on the clinical characteristics of the abdominal pain episodes, the exclusion of any alternative diagnosis, and the relief of symptoms during and after pregnancy, a final diagnosis of abdominal migraine could be established. A skilled emergency physician should always consider abdominal migraine in the differential diagnosis of patients admitted to the ED with abdominal pain, especially when the attacks are recurrent and no alternative diagnosis can be clearly established. PMID:25616589

  8. Development of a novel synthetic material to close abdominal wall defects.

    PubMed

    Cnota, M A; Aliabadi-Wahle, S; Choe, E U; Jacob, J T; Flint, L M; Ferrara, J J

    1998-05-01

    To compare the efficacy of a novel synthetic material (TMS-2) with polytetrafluoroethylene, polypropylene (Marlex), and primary closure of experimentally fashioned clean and contaminated abdominal wounds, 1-cm2 abdominal wall defects were created in each of the four abdominal quadrants of rats (n = 10). Patches of each material were used to repair three of these defects, the fourth being primarily closed. A second group of rats (n = 7) underwent the same operative protocol; however, peritonitis was induced at the time of surgery using a fecal inoculation technique. Animals were killed 2 weeks later, and surface area and severity of formed adhesions were assessed by a "blinded" observer. All closure techniques were successful insofar as none demonstrated fascial dehiscence. Compared with each synthetic material, the surface area of formed adhesions was smaller after primary closure in clean and in contaminated conditions; however, the three synthetic materials were equally matched regarding surface area of adhesions under both conditions. In the face of fecal contamination, TMS-2 proved identical to primary closure, each generating significantly (P < 0.02) milder adhesions than the other prosthetic materials. It is concluded that the TMS-2 may prove of clinical benefit to repair abdominal wall defects. PMID:9585774

  9. Adhesion hysteresis of silane coated microcantilevers

    SciTech Connect

    DE BOER,MAARTEN P.; KNAPP,JAMES A.; MICHALSKE,TERRY A.; SRINIVASAN,U.; MABOUDIAN,R.

    2000-04-17

    The authors have developed a new experimental approach for measuring hysteresis in the adhesion between micromachined surfaces. By accurately modeling the deformations in cantilever beams that are subject to combined interfacial adhesion and applied electrostatic forces, they determine adhesion energies for advancing and receding contacts. They draw on this new method to examine adhesion hysteresis for silane coated micromachined structures and found significant hysteresis for surfaces that were exposed to high relative humidity (RH) conditions. Atomic force microscopy studies of these surfaces showed spontaneous formation of agglomerates that they interpreted as silages that have irreversibly transformed from uniform surface layers at low RH to isolated vesicles at high RH. They used contact deformation models to show that the compliance of these vesicles could reasonably account for the adhesion hysteresis that develops at high RH as the surfaces are forced into contact by an externally applied load.

  10. Intra-abdominal hypertension and acute pancreatitis.

    PubMed

    Mifkovic, A; Skultety, J; Sykora, P; Prochotsky, A; Okolicany, R

    2013-01-01

    Intra-abdominal hypertension (IAH) contributes to organ dysfunction and leads to the development of the abdominal compartment syndrome (ACS). IAH and ACS are relatively frequent findings in patiens with severe acute pancreatitis (SAP) and are associated with deterioration in organ functions. The most affected are cardiovascular, respiratory and renal functions. The incidence of IAH in patients with SAP is approximately 60-80%. There is an accumulating evidence in human and animal studies that changes of perfusion, particularly to the microvasculature, are crucial events in the progression of acute pancreatitis (AP). The perfusion of the small and large intestine is impaired due to reduced arterial pressure, increased vascular resistence and diminished portal blood flow. Bacterial translocation has been described in patients with ACS, and this may apply to patients with SAP. Approximately 30-40% of SAP patients develop ACS because of pancreatic (retroperitoneal) inflammation, peripancreatic tissue edema, formation of fluid collections or abdominal distension. Surgical debridement was the preferred treatment to control necrotizing pancreatitis in the past. However, the management of necrotizing pancreatitis has changed over the last decade. The main objective of this article is to describe the association between IAH and AP and to emphasize this situation in clinical praxis as well (Fig. 1, Ref. 38). PMID:23406186

  11. The evolution of adhesiveness as a social adaptation.

    PubMed

    Garcia, Thomas; Doulcier, Guilhem; De Monte, Silvia

    2015-01-01

    Cellular adhesion is a key ingredient to sustain collective functions of microbial aggregates. Here, we investigate the evolutionary origins of adhesion and the emergence of groups of genealogically unrelated cells with a game-theoretical model. The considered adhesiveness trait is costly, continuous and affects both group formation and group-derived benefits. The formalism of adaptive dynamics reveals two evolutionary stable strategies, at each extreme on the axis of adhesiveness. We show that cohesive groups can evolve by small mutational steps, provided the population is already endowed with a minimum adhesiveness level. Assortment between more adhesive types, and in particular differential propensities to leave a fraction of individuals ungrouped at the end of the aggregation process, can compensate for the cost of increased adhesiveness. We also discuss the change in the social nature of more adhesive mutations along evolutionary trajectories, and find that altruism arises before directly beneficial behavior, despite being the most challenging form of cooperation. PMID:26613415

  12. The effect of polyethylene glycol adhesion barrier (Spray Gel) on preventing peritoneal adhesions.

    PubMed

    Dasiran, F; Eryilmaz, R; Isik, A; Okan, I; Somay, A; Sahin, M

    2015-01-01

    The prominent cells in the late phase of wound healing during proliferation and matrix deposition are fibroblasts. Foreign materials in the operation site like prosthesis prolong the inflammation and induce fibroblast proliferation (8). 3 different prostheses used in this study induced chronic inflammation and fibrosis and provided an effective repair. Dense and thick adhesions due to fibrosis also induced strong adhesions to omentum and small intestine if only polypropylene mesh used for hernia repair. However, there was no difference between SprayGel treated polypropylene mesh and Sepramesh when compared for fibrosis. It also prevents the intraabdominal adhesion formation. It is nontoxic, sticky adherent, non- immigrant and easy to use both in open and laparoscopic surgeries. This experimental study revealed that polyethyleneglycol applied polypropylene mesh accomplishes hernia repair with significantly less adhesion formation than polypropylene mesh alone while securing a remarkable economy than adhesion barrier coated dual meshes (Tab. 6, Fig. 7, Ref. 23). Text in PDF www.elis.sk. PMID:26084740

  13. Penetrating abdominal trauma.

    PubMed

    Henneman, P L

    1989-08-01

    The management of patients with penetrating abdominal trauma is outlined in Figure 1. Patients with hemodynamic instability, evisceration, significant gastrointestinal bleeding, peritoneal signs, gunshot wounds with peritoneal violation, and type 2 and 3 shotgun wounds should undergo emergency laparotomy. The initial ED management of these patients includes airway management, monitoring of cardiac rhythm and vital signs, history, physical examination, and placement of intravenous lines. Blood should be obtained for initial hematocrit, type and cross-matching, electrolytes, and an alcohol level or drug screen as needed. Initial resuscitation should utilize crystalloid fluid replacement. If more than 2 liters of crystalloid are needed to stabilize an adult (less in a child), blood should be given. Group O Rh-negative packed red blood cells should be immediately available for a patient in impending arrest or massive hemorrhage. Type-specific blood should be available within 15 minutes. A patient with penetrating thoracic and high abdominal trauma should receive a portable chest x-ray, and a hemo- or pneumothorax should be treated with tube thoracostomy. An unstable patient with clinical signs consistent with a pneumothorax, however, should receive a tube thoracostomy prior to obtaining roentgenographic confirmation. If time permits, a nasogastric tube and Foley catheter should be placed, and the urine evaluated for blood (these procedures can be performed in the operating room). If kidney involvement is suspected because of hematuria or penetrating trauma in the area of a kidney or ureter in a patient requiring surgery, a single-shot IVP should be performed either in the ED or the operating room. An ECG is important in patients with possible cardiac involvement and in patients over the age of 40 going to the operating room. Tetanus status should be updated, and appropriate antibiotics covering bowel flora should be given. Operative management should rarely be delayed

  14. Economics of abdominal wall reconstruction.

    PubMed

    Bower, Curtis; Roth, J Scott

    2013-10-01

    The economic aspects of abdominal wall reconstruction are frequently overlooked, although understandings of the financial implications are essential in providing cost-efficient health care. Ventral hernia repairs are frequently performed surgical procedures with significant economic ramifications for employers, insurers, providers, and patients because of the volume of procedures, complication rates, the significant rate of recurrence, and escalating costs. Because biological mesh materials add significant expense to the costs of treating complex abdominal wall hernias, the role of such costly materials needs to be better defined to ensure the most cost-efficient and effective treatments for ventral abdominal wall hernias. PMID:24035086

  15. Acute incarcerated external abdominal hernia

    PubMed Central

    Yang, Xue-Fei

    2014-01-01

    External abdominal hernia occurs when abdominal organs or tissues leave their normal anatomic site and protrude outside the skin through the congenital or acquired weakness, defects or holes on the abdominal wall, including inguinal hernia, umbilical hernia, femoral hernia and so on. Acute incarcerated hernia is a common surgical emergency. With advances in minimally invasive devices and techniques, the diagnosis and treatment have witnessed major changes, such as the use of laparoscopic surgery in some cases to achieve minimally invasive treatment. However, strict adherence to the indications and contraindications is still required. PMID:25489584

  16. Malignant Schwannoma of Anterior Abdominal Wall: Report of a Case

    PubMed Central

    Khorgami, Zhamak; Nasiri, Shirzad; Rezakhanlu, Freshteh; Sodagari, Nassim

    2009-01-01

    Malignant schwannoma of the anterior abdominal wall nerves is extremely rare. Malignant peripheral nerve sheath tumors (MPNST) represent approximately 10% of all soft tissue sarcomas and it is found in 4% of patients with neurofibromatosis 1. We present a case of malignant schwannoma in a 28-year-old female patient with neurofibromatosis 1. She presented with a painful mass in the right upper quadrant of her abdomen. The tumor location was in the abdominal wall in explorative laparatomy and malignant schwannoma was diagnosed in pathologic assessment. The tumor recurred in 3 months and computed tomography showed two masses in the right side of abdominopelvic cavity. Thereafter, second complete surgical resection was performed and pathologic finding was the same. In spite of administering chemotherapy after second surgery,the tumor recurred and magnetic resonance imaging finding showed a huge heterogeneously enhancing mass with adhesion to the inner side of the abdominal wall. The patient died because of acute respiratory failure due to multiple bilateral pulmonary metastases. Tumor location and rapid recurrence was unique in our patient. Keywords Malignant peripheral nerve sheath tumor; Malignant schwannoma; Abdominal wall PMID:22461875

  17. Diagnosis of acute abdominal pain in older patients.

    PubMed

    Lyon, Corey; Clark, Dwayne C

    2006-11-01

    Acute abdominal pain is a common presenting complaint in older patients. Presentation may differ from that of the younger patient and is often complicated by coexistent disease, delays in presentation, and physical and social barriers. The physical examination can be misleadingly benign, even with catastrophic conditions such as abdominal aortic aneurysm rupture and mesenteric ischemia. Changes that occur in the biliary system because of aging make older patients vulnerable to acute cholecystitis, the most common indication for surgery in this population. In older patients with appendicitis, the initial diagnosis is correct only one half of the time, and there are increased rates of perforation and mortality when compared with younger patients. Medication use, gallstones, and alcohol use increase the risk of pancreatitis, and advanced age is an indicator of poor prognosis for this disease. Diverticulitis is a common cause of abdominal pain in the older patient; in appropriately selected patients, it may be treated on an outpatient basis with oral antibiotics. Small and large bowel obstructions, usually caused by adhesive disease or malignancy, are more common in the aged and often require surgery. Morbidity and mortality among older patients presenting with acute abdominal pain are high, and these patients often require hospitalization with prompt surgical consultation. PMID:17111893

  18. PH dependent adhesive peptides

    DOEpatents

    Tomich, John; Iwamoto, Takeo; Shen, Xinchun; Sun, Xiuzhi Susan

    2010-06-29

    A novel peptide adhesive motif is described that requires no receptor or cross-links to achieve maximal adhesive strength. Several peptides with different degrees of adhesive strength have been designed and synthesized using solid phase chemistries. All peptides contain a common hydrophobic core sequence flanked by positively or negatively charged amino acids sequences.

  19. Evaluation of the Effectiveness of Peritoneal Adhesion Prevention Devices in a Rat Model

    PubMed Central

    Poehnert, D; Grethe, L; Maegel, L; Jonigk, D; Lippmann, T; Kaltenborn, A; Schrem, H; Klempnauer, J; Winny, M

    2016-01-01

    Background: Abdominal operations are followed by adhesions, a prevalent cause of abdominal pain, and the most frequent cause for bowel obstruction and secondary female infertility. This rat study addresses adhesion prevention capability of Adept®, Interceed®, Seprafilm®, and a novel device, 4DryField® PH which is provided as powder and generates its effect as gel. Methods: Sixty-eight male Lewis rats had cecal abrasion and creation of an equally sized abdominal wall defect, and were grouped randomly: A control group without treatment (n=10); two groups treated with 4DryField® PH using premixed gel (n=15) or in-situ gel technique (n=16); one group each was treated with Seprafilm® (n=8), Interceed® (n=9), or Adept® (n=10). Sacrifice was on day 7 to evaluate incidence, quality, and quantity of adhesions, as expressed via adhesion reduction rate (AR). Histologic specimens were evaluated. Statistical analyses used ANOVA and unpaired t-tests. Results: 4DryField® PH significantly reduced incidence and severity of adhesions both as premixed gel (AR: 85.2%) and as in-situ made gel (AR: 100%), a comparison between these two application techniques showed no differences in efficacy. Seprafilm® did not reduce incidence but severity of adhesions significantly (AR: 53.5%). With Interceed® (AR: 3.7%) and Adept® (AR: 16.1%) no significant adhesion-reduction was achieved. Except for inflammatory response with Interceed®, histopathology showed good tissue compatibility of all other devices. Conclusion: 4DryField® PH and Seprafilm® showed significant adhesion prevention capabilities. 4DryField® PH achieved the highest adhesion prevention effectiveness without restrictions concerning mode of application and compatibility and, thus, is a promising strategy to prevent abdominal adhesions. PMID:27429589

  20. Evaluation of progestogens for postoperative adhesion prevention.

    PubMed

    Beauchamp, P J; Quigley, M M; Held, B

    1984-10-01

    Progesterone (P) has been shown to have potent antiinflammatory and immunosuppressive properties. Previous reports have suggested that the use of P decreases postoperative adhesion formation. To further evaluate the role of pharmacologic doses of progestogens in adhesion prevention, 42 mature New Zealand White rabbits underwent standardized injuries to the uterine horns, fimbriae, and pelvic peritoneum and received one of six treatments. Group S had intraperitoneal placement of normal saline (0.9%); group H received intraperitoneal placement of 32% dextran 70; group IM-P received intramuscular P-in-oil 10 days before and after laparotomy in addition to intraperitoneal saline; group IP-P had intraperitoneal placement of an aqueous P suspension; group DP received medroxyprogesterone acetate intraperitoneally; and group C received no intramuscular or intraperitoneal adhesion-prevention agents. The animals were sacrificed 6 weeks after laparotomy, and the adhesions were scored. Intraperitoneal saline (group S) significantly reduced the amount of adhesions when compared with the control group (C) (P less than 0.05). No significant difference was observed when group S was compared with group H. Intramuscular P added to saline (group IM-P) did not cause further reduction in adhesions when compared with group S. Both group IP-P and group DP had more adhesions than did group S (P less than 0.01). These data fail to support previous claims regarding adhesion prevention by the use of locally or parenterally administered progestogens. PMID:6237937

  1. Micromanaging abdominal aortic aneurysms.

    PubMed

    Maegdefessel, Lars; Spin, Joshua M; Adam, Matti; Raaz, Uwe; Toh, Ryuji; Nakagami, Futoshi; Tsao, Philip S

    2013-01-01

    The contribution of abdominal aortic aneurysm (AAA) disease to human morbidity and mortality has increased in the aging, industrialized world. In response, extraordinary efforts have been launched to determine the molecular and pathophysiological characteristics of the diseased aorta. This work aims to develop novel diagnostic and therapeutic strategies to limit AAA expansion and, ultimately, rupture. Contributions from multiple research groups have uncovered a complex transcriptional and post-transcriptional regulatory milieu, which is believed to be essential for maintaining aortic vascular homeostasis. Recently, novel small noncoding RNAs, called microRNAs, have been identified as important transcriptional and post-transcriptional inhibitors of gene expression. MicroRNAs are thought to "fine tune" the translational output of their target messenger RNAs (mRNAs) by promoting mRNA degradation or inhibiting translation. With the discovery that microRNAs act as powerful regulators in the context of a wide variety of diseases, it is only logical that microRNAs be thoroughly explored as potential therapeutic entities. This current review summarizes interesting findings regarding the intriguing roles and benefits of microRNA expression modulation during AAA initiation and propagation. These studies utilize disease-relevant murine models, as well as human tissue from patients undergoing surgical aortic aneurysm repair. Furthermore, we critically examine future therapeutic strategies with regard to their clinical and translational feasibility. PMID:23852016

  2. Abdominal aortic feminism.

    PubMed

    Mortimer, Alice Emily

    2014-01-01

    A 79-year-old woman presented to a private medical practice 2 years previously for an elective ultrasound screening scan. This imaging provided the evidence for a diagnosis of an abdominal aortic aneurysm (AAA) to be made. Despite having a number of recognised risk factors for an AAA, her general practitioner at the time did not follow the guidance set out by the private medical professional, that is, to refer the patient to a vascular specialist to be entered into a surveillance programme and surgically evaluated. The patient became symptomatic with her AAA, was admitted to hospital and found to have a tender, symptomatic, 6 cm leaking AAA. She consented for an emergency open AAA repair within a few hours of being admitted to hospital, despite the 50% perioperative mortality risk. The patient spent 4 days in intensive care where she recovered well. She was discharged after a 12 day hospital stay but unfortunately passed away shortly after her discharge from a previously undiagnosed gastric cancer. PMID:25398912

  3. MicroRNAs in Abdominal Aortic Aneurysm.

    PubMed

    Adam, Matti; Raaz, Uwe; Spin, Joshua M; Tsao, Philip S

    2015-01-01

    Abdominal aortic aneurysms (AAA) are an important source of morbidity and mortality in the U.S. and worldwide. Treatment options are limited, with open surgery or endovascular repair remaining the only curative treatments. Classical cardiovascular medications have generally failed to prevent or significantly alter AAA formation or progression. Therefore, there is a tremendous need for better therapeutic approaches. With increasing knowledge of microRNA (miR) regulation in the context of cardiovascular disease, and with improving technical options permitting alteration of miRexpression levels in vitro and in vivo, we are offered a glimpse into the diagnostic and therapeutic possibilities of using miRs to treat vascular pathobiology. This review focuses on the role of miRs in aneurysmal disease of the abdominal aorta, summarizing recent publications regarding this topic, and outlining known effects of relevant miRs in AAA formation, including miR-21 and miR-29b. Despite there being only limited studies available, several other miRs also display clear potential for alteration of the disease process including miR-26a, the miR-17-92-cluster, miRs-221/222, miR-133 and miR-146a. While studies have shown that miRs can regulate the activity and interplay of vascular inflammatory cells, endothelial cells, smooth muscle cells and fibroblasts, all key elements leading to AAA formation, much work remains to be done. PMID:23713862

  4. [Abdominal wall closure by incisional hernia and herniation after laparostoma].

    PubMed

    Mischinger, H-J; Kornprat, P; Werkgartner, G; El Shabrawi, A; Spendel, S

    2010-03-01

    As hernias and abdominal wall defects have a variety of etiologies each with its own complications and comorbidities in various constellations, efficient treatment requires patient-oriented management. There is no recommended standard treatment and the very different clinical pictures demand an individualized interdisciplinary approach. Particularly in the case of complicated hernias, the planning of the operation should focus on the problems posed by the individual patient. Treatment mainly depends on the etiology of the hernia, immediate or long-term complications and the efficiency of individual repair techniques. Abdominal wall repair for recurrent herniation requires direct closure of the fascia generally using the sublay technique with a lightweight mesh. It is still unclear whether persistent inflammation, mesh dislocation, fistula formation or other long-term complications are due to certain materials or to the surgical technique. With mesh infections it has been shown to be advantageous to remove a polytetrafluoroethylene (PTFE) mesh, while the combination of systemic and local treatment appears to suffice for a polypropylene or polyester mesh. Heavier meshes in the sublay position or plastic reconstruction with autologous tissue are indicated as substitutes for the abdominal wall for giant hernias, repeated recurrences and large abdominal wall defects. A laparostoma is increasingly more often created to treat septic intra-abdominal processes but is very often responsible for a complicated hernia. If primary repair of the abdominal wall is not an option, resorbable material or split skin is used for coverage under the auspices of a planned hernia repair. PMID:20145901

  5. JAMA Patient Page: Abdominal Hernia

    MedlinePlus

    ... an operation. Umbilical hernia Abdominal wall Intestinal loop Peritoneum Skin Peritoneum Umbilical annulus SYMPTOMS The first symptom of a ... vomiting, or constipation. Inguinal hernia Indirect inguinal hernia Peritoneum Deep inguinal ring Inguinal canal Superficial inguinal ring ...

  6. Functional Abdominal Pain in Children

    MedlinePlus

    ... At low doses, these medicines can be excellent pain relievers for some children. A fearful, anxious, or depressed child however should be fully assessed by a psychiatrist or psychologist. Some psychological treatments that help children cope with functional abdominal pain ...

  7. Caspase-1-independent IL-1 release mediates blister formation in autoantibody-induced tissue injury through modulation of endothelial adhesion molecules.

    PubMed

    Sadeghi, Hengameh; Lockmann, Anike; Hund, Anna-Carina; Samavedam, Unni K S R L; Pipi, Elena; Vafia, Katerina; Hauenschild, Eva; Kalies, Kathrin; Pas, Hendri H; Jonkman, Marcel F; Iwata, Hiroaki; Recke, Andreas; Schön, Michael P; Zillikens, Detlef; Schmidt, Enno; Ludwig, Ralf J

    2015-04-15

    Although reports documented aberrant cytokine expression in autoimmune bullous dermatoses (AIBDs), cytokine-targeting therapies have not been established in these disorders. We showed previously that IL-6 treatment protected against tissue destruction in experimental epidermolysis bullosa acquisita (EBA), an AIBD caused by autoantibodies to type VII collagen (COL7). The anti-inflammatory effects of IL-6 were mediated by induction of IL-1ra, and prophylactic IL-1ra administration prevented blistering. In this article, we demonstrate elevated serum concentrations of IL-1β in both mice with experimental EBA induced by injection of anti-COL7 IgG and in EBA patients. Increased IL-1α and IL-1β expression also was observed in the skin of anti-COL7 IgG-injected wild-type mice compared with the significantly less diseased IL-1R-deficient or wild-type mice treated with the IL-1R antagonist anakinra or anti-IL-1β. These findings suggested that IL-1 contributed to recruitment of inflammatory cells into the skin. Accordingly, the expression of ICAM-1 was decreased in IL-1R-deficient and anakinra-treated mice injected with anti-COL7. This effect appeared to be specifically attributable to IL-1 because anakinra blocked the upregulation of different endothelial adhesion molecules on IL-1-stimulated, but not on TNF-α-stimulated, cultured endothelial cells. Interestingly, injection of caspase-1/11-deficient mice with anti-COL7 IgG led to the same extent of skin lesions as in wild-type mice. Collectively, our data suggest that IL-1, independently of caspase-1, contributes to the pathogenesis of EBA. Because anti-IL-1β in a prophylactic setting and anakinra in a quasi-therapeutic setting (i.e., when skin lesions had already developed) improved experimental EBA, IL-1 appears to be a potential therapeutic target for EBA and related AIBDs. PMID:25795756

  8. Abdominal emergencies in the geriatric patient

    PubMed Central

    2014-01-01

    Abdominal pain is one of the most frequent reasons that elderly people visit the emergency department (ED). In this article, we review the deadliest causes of abdominal pain in this population, including mesenteric ischemia, abdominal aortic aneurysm, and appendicitis and potentially lethal non-abdominal causes. We also highlight the pitfalls in diagnosing, or rather misdiagnosing, these clinical entities. PMID:25635203

  9. Abdominal intrauterine vacuum aspiration.

    PubMed

    Tjalma, W A A

    2014-01-01

    Evaluating and "cleaning" of the uterine cavity is probably the most performed operation in women. It is done for several reasons: abortion, evaluation of irregular bleeding in premenopausal period, and postmenopausal bleeding. Abortion is undoubtedly the number one procedure with more than 44 million pregnancies terminated every year. This procedure should not be underestimated and a careful preoperative evaluation is needed. Ideally a sensitive pregnancy test should be done together with an ultrasound in order to confirm a uterine pregnancy, excluding extra-uterine pregnancy, and to detect genital and/or uterine malformations. Three out of four abortions are performed by surgical methods. Surgical methods include a sharp, blunt, and suction curettage. Suction curettage or vacuum aspiration is the preferred method. Despite the fact that it is a relative safe procedure with major complications in less than one percent of cases, it is still responsible for 13% of all maternal deaths. All the figures have not declined in the last decade. Trauma, perforation, and bleeding are a danger triage. When there is a perforation, a laparoscopy should be performed immediately, in order to detect intra-abdominal lacerations and bleeding. The bleeding should be stopped as soon as possible in order to not destabilize the patient. When there is a perforation in the uterus, this "entrance" can be used to perform the curettage. This is particularly useful if there is trauma of the isthmus and uterine wall, and it is difficult to identify the uterine canal. A curettage is a frequent performed procedure, which should not be underestimated. If there is a perforation in the uterus, then this opening can safely be used for vacuum aspiration. PMID:25134300

  10. Interceed and Estrogen Reduce Uterine Adhesions and Fibrosis and Improve Endometrial Receptivity in a Rabbit Model of Intrauterine Adhesions.

    PubMed

    Cai, Huihua; Li, Huijuan; He, Yuanli

    2016-09-01

    Intrauterine adhesions (IUA) remain a major cause of infertility. Interceed, a regenerated cellulose adhesion barrier, is used to prevent adhesions in abdominal cavity. This study aimed to determine whether Interceed could reduce adhesions and tissue fibrosis and improve endometrial receptivity (ER) in rabbit. Rabbits were randomized into 6 groups: sham operation, Interceed control, IUA model, Interceed therapy, estrogen therapy, and combination therapy. Four rabbits per group were euthanized to evaluate adhesion severity on the day before intervention and day 7, 14, and 28 after intervention. Number of endometrial glands and degree of endometrial fibrosis acted as markers for adhesion severity. Pseudopregnancy was induced in the remainder, and 8 rabbits per group were killed for assessing ER on days 6, 7, and 8 of pseudopregnancy by ανβ3 integrin and pinopode. We found that Interceed or estrogen therapy led to significant improvement in the adhesion severity on day 28 after intervention, respectively, compared to IUA model group (all P < .05). However, after combination therapy, such improvement achieved comparable to sham operation group as early as day 14 after intervention (glands, P = .711, fibrosis, P = .154). Among the IUA models treated, ER was highest after combination therapy on day 7 of pseudopregnancy, similar to sham operation group (integrin, P = .352, pinopode, P = .154). In conclusion, Interceed and estrogen reduce adhesions and tissue fibrosis and improve ER in a rabbit model and may be novel therapeutic approaches for infertility resulting from IUA. PMID:26895816

  11. 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. PMID:26450606

  12. FHA-Mediated Cell-Substrate and Cell-Cell Adhesions Are Critical for Bordetella pertussis Biofilm Formation on Abiotic Surfaces and in the Mouse Nose and the Trachea

    PubMed Central

    Serra, Diego O.; Conover, Matt S.; Arnal, Laura; Sloan, Gina Parise; Rodriguez, María E.; Yantorno, Osvaldo M.; Deora, Rajendar

    2011-01-01

    Bordetella spp. form biofilms in the mouse nasopharynx, thereby providing a potential mechanism for establishing chronic infections in humans and animals. Filamentous hemagglutinin (FHA) is a major virulence factor of B. pertussis, the causative agent of the highly transmissible and infectious disease, pertussis. In this study, we dissected the role of FHA in the distinct biofilm developmental stages of B. pertussis on abiotic substrates and in the respiratory tract by employing a murine model of respiratory biofilms. Our results show that the lack of FHA reduced attachment and decreased accumulation of biofilm biomass on artificial surfaces. FHA contributes to biofilm development by promoting the formation of microcolonies. Absence of FHA from B. pertussis or antibody-mediated blockade of surface-associated FHA impaired the attachment of bacteria to the biofilm community. Exogenous addition of FHA resulted in a dose-dependent inhibitory effect on bacterial association with the biofilms. Furthermore, we show that FHA is important for the structural integrity of biofilms formed on the mouse nose and trachea. Together, these results strongly support the hypothesis that FHA promotes the formation and maintenance of biofilms by mediating cell-substrate and inter-bacterial adhesions. These discoveries highlight FHA as a key factor in establishing structured biofilm communities in the respiratory tract. PMID:22216115

  13. A randomized controlled experimental study comparing chitosan coated polypropylene mesh and Proceed™ mesh for abdominal wall defect closure

    PubMed Central

    Jayanth, S.T.; Pulimood, Anna; Abraham, Deepak; Rajaram, A.; Paul, M.J.; Nair, Aravindan

    2015-01-01

    Background Abdominal wall defects and hernias are commonly repaired with synthetic or biological materials. Adhesions and recurrences are a common problem. A study was conducted to compare Chitosan coated polypropylene mesh and a polypropylene–polydioxanone composite with oxidized cellulose coating mesh (Proceed™) in repair of abdominal wall defect in a Rabbit hernia model. Methods A randomized controlled experimental study was done on twelve New Zealand white rabbits. A ventral abdominal defect was created in each of the rabbits. The rabbits were divided into two groups. In one group the defect was repaired with Chitosan coated polypropylene mesh and Proceed mesh™ in the other. The rabbits were operated in two phases. They were followed up at four weeks and twelve weeks respectively after which the rabbits were sacrificed. They were evaluated by open exploration and histopathological examination. Their efficacy in reducing adhesion and ability of remodeling and tissue integration were studied. Results There was no statistical significance in the area of adhesion, the force required to remove the adhesions, tissue integration and remodeling between Chitosan and Proceed™ group. Histological analysis revealed that the inflammatory response, fibrosis, material degradation and remodeling were similar in both the groups. There were no hernias, wound infection or dehiscence in any of the studied animals. Conclusion Chitosan coated polypropylene mesh was found to have similar efficacy to Proceed™ mesh. Chitosan coated polypropylene mesh, can act as an anti adhesive barrier when used in the repair of incisional hernias and abdominal wall defects. PMID:26594357

  14. Comparison of novel synthetic materials with traditional methods to repair exposed abdominal wall fascial defects.

    PubMed

    Aliabadi-Wahle, S; Cnota, M; Choe, E; Jacob, J T; Flint, L M; Ferrara, J J

    1998-01-01

    Repair of large abdominal wall defects is a challenge, particularly when full-thickness tissue loss prohibits coverage of the fascial repair. Two novel synthetic materials (TMS-1 and TMS-2) have been shown to be better accepted than expanded polytetrafluoroethylene (Gore-Tex), and polypropylene (Marlex) in the closure of clean and contaminated fascial wounds that are immediately covered by skin/soft tissue. Therefore, 1-cm2 abdominal wall defects were created in each of the four quadrants of rat groups. Gore-Tex, Marlex, and TMS-1 or TMS-2 were used to repair three defects, the fourth being primarily closed. To ensure that each repair remained exposed, skin edges were sutured to underlying muscle. Additional animal groups underwent the same protocol; however, peritonitis was induced at surgery using a fecal inoculum technique. Animals were sacrificed 2 weeks later, at which time a blinded observer assessed the surface area and severity of adhesions. In clean wounds, the surface area of formed adhesions was less (p < .004) after primary closure than each synthetic material; among the synthetics, TMS-2 caused significantly (p < .01) less extensive adhesions than Marlex. In addition, the severity of adhesions to TMS-2 was comparable to that of defects closed primarily, and less severe (p < .02) than those formed to Gore-Tex and Marlex. In animals with peritonitis, primary closure caused less extensive (p < .03) adhesions than Marlex and Gore-Tex and significantly (p < .002) less severe adhesions than Marlex, Gore-Tex, and TMS-2. However, the severity of adhesions formed to TMS-1 repairs proved comparable to primarily closed wounds. These experiments reaffirm the tenet that, whenever possible, abdominal wounds should undergo primary fascial closure. When soft tissue coverage over the repair cannot be achieved, TMS-2 is well tolerated in clean wounds. However, the superiority of TMS-1 over the other synthetic materials in contaminated wounds suggests it may also

  15. Unique Footprint in the scl1.3 Locus Affects Adhesion and Biofilm Formation of the Invasive M3-Type Group A Streptococcus

    PubMed Central

    Bachert, Beth A.; Choi, Soo J.; LaSala, Paul R.; Harper, Tiffany I.; McNitt, Dudley H.; Boehm, Dylan T.; Caswell, Clayton C.; Ciborowski, Pawel; Keene, Douglas R.; Flores, Anthony R.; Musser, James M.; Squeglia, Flavia; Marasco, Daniela; Berisio, Rita; Lukomski, Slawomir

    2016-01-01

    The streptococcal collagen-like proteins 1 and 2 (Scl1 and Scl2) are major surface adhesins that are ubiquitous among group A Streptococcus (GAS). Invasive M3-type strains, however, have evolved two unique conserved features in the scl1 locus: (i) an IS1548 element insertion in the scl1 promoter region and (ii) a nonsense mutation within the scl1 coding sequence. The scl1 transcript is drastically reduced in M3-type GAS, contrasting with a high transcription level of scl1 allele in invasive M1-type GAS. This leads to a lack of Scl1 expression in M3 strains. In contrast, while scl2 transcription and Scl2 production are elevated in M3 strains, M1 GAS lack Scl2 surface expression. M3-type strains were shown to have reduced biofilm formation on inanimate surfaces coated with cellular fibronectin and laminin, and in human skin equivalents. Repair of the nonsense mutation and restoration of Scl1 expression on M3-GAS cells, restores biofilm formation on cellular fibronectin and laminin coatings. Inactivation of scl1 in biofilm-capable M28 and M41 strains results in larger skin lesions in a mouse model, indicating that lack of Scl1 adhesin promotes bacterial spread over localized infection. These studies suggest the uniquely evolved scl1 locus in the M3-type strains, which prevents surface expression of the major Scl1 adhesin, contributed to the emergence of the invasive M3-type strains. Furthermore these studies provide insight into the molecular mechanisms mediating colonization, biofilm formation, and pathogenesis of group A streptococci.

  16. Penile adhesion: the hidden complication of circumcision.

    PubMed

    Gracely-Kilgore, K A

    1984-05-01

    A penile or prepuce adhesion can occur after a circumcision if the remaining skin is not retracted after the circumcision has healed. When a circumcision is done, tissue which would normally be intact is split. Unless proper care is taken, the epithelium of the inner prepuce at the point where the foreskin was removed can reattach to the epithelium of the glans. The result of this is a penile adhesion. Usually the adhesions can be released by simple retraction. Sometimes, however, the fusion is so complete that simple retraction will not work, and the child must be referred to a urologist. Another problem is that smegma or bacteria can collect under the adhesion if it covers the preputial cavity and cause infection. Professionals must look for this problem, and parents must be taught how to care for the normal circumcised penis so that penile adhesions do not develop. This article discusses the formation and identification of penile adhesions, the process by which adhesions can be released, when a referral to a urologist is necessary and the proper care for the circumcised penis. PMID:6728346

  17. Tongue adhesion in the horned frog Ceratophrys sp.

    NASA Astrophysics Data System (ADS)

    Kleinteich, Thomas; Gorb, Stanislav N.

    2014-06-01

    Frogs are well-known to capture elusive prey with their protrusible and adhesive tongues. However, the adhesive performance of frog tongues and the mechanism of the contact formation with the prey item remain unknown. Here we measured for the first time adhesive forces and tongue contact areas in living individuals of a horned frog (Ceratophrys sp.) against glass. We found that Ceratophrys sp. generates adhesive forces well beyond its own body weight. Surprisingly, we found that the tongues adhered stronger in feeding trials in which the coverage of the tongue contact area with mucus was relatively low. Thus, besides the presence of mucus, other features of the frog tongue (surface profile, material properties) are important to generate sufficient adhesive forces. Overall, the experimental data shows that frog tongues can be best compared to pressure sensitive adhesives (PSAs) that are of common technical use as adhesive tapes or labels.

  18. Adhesion at metal interfaces

    NASA Technical Reports Server (NTRS)

    Banerjea, Amitava; Ferrante, John; Smith, John R.

    1991-01-01

    A basic adhesion process is defined, the theory of the properties influencing metallic adhesion is outlined, and theoretical approaches to the interface problem are presented, with emphasis on first-principle calculations as well as jellium-model calculations. The computation of the energies of adhesion as a function of the interfacial separation is performed; fully three-dimensional calculations are presented, and universality in the shapes of the binding energy curves is considered. An embedded-atom method and equivalent-crystal theory are covered in the framework of issues involved in practical adhesion.

  19. Abdominal radiation causes bacterial translocation

    SciTech Connect

    Guzman-Stein, G.; Bonsack, M.; Liberty, J.; Delaney, J.P.

    1989-02-01

    The purpose of this study was to determine if a single dose of radiation to the rat abdomen leads to bacterial translocation into the mesenteric lymph nodes (MLN). A second issue addressed was whether translocation correlates with anatomic damage to the mucosa. The radiated group (1100 cGy) which received anesthesia also was compared with a control group and a third group which received anesthesia alone but no abdominal radiation. Abdominal radiation lead to 100% positive cultures of MLN between 12 hr and 4 days postradiation. Bacterial translocation was almost nonexistent in the control and anesthesia group. Signs of inflammation and ulceration of the intestinal mucosa were not seen until Day 3 postradiation. Mucosal damage was maximal by Day 4. Bacterial translocation onto the MLN after a single dose of abdominal radiation was not apparently dependent on anatomical, histologic damage of the mucosa.

  20. Assay of Adhesion Under Shear Stress for the Study of T Lymphocyte-Adhesion Molecule Interactions.

    PubMed

    Strazza, Marianne; Azoulay-Alfaguter, Inbar; Peled, Michael; Mor, Adam

    2016-01-01

    Overall, T cell adhesion is a critical component of function, contributing to the distinct processes of cellular recruitment to sites of inflammation and interaction with antigen presenting cells (APC) in the formation of immunological synapses. These two contexts of T cell adhesion differ in that T cell-APC interactions can be considered static, while T cell-blood vessel interactions are challenged by the shear stress generated by circulation itself. T cell-APC interactions are classified as static in that the two cellular partners are static relative to each other. Usually, this interaction occurs within the lymph nodes. As a T cell interacts with the blood vessel wall, the cells arrest and must resist the generated shear stress.(1,2) These differences highlight the need to better understand static adhesion and adhesion under flow conditions as two distinct regulatory processes. The regulation of T cell adhesion can be most succinctly described as controlling the affinity state of integrin molecules expressed on the cell surface, and thereby regulating the interaction of integrins with the adhesion molecule ligands expressed on the surface of the interacting cell. Our current understanding of the regulation of integrin affinity states comes from often simplistic in vitro model systems. The assay of adhesion using flow conditions described here allows for the visualization and accurate quantification of T cell-epithelial cell interactions in real time following a stimulus. An adhesion under flow assay can be applied to studies of adhesion signaling within T cells following treatment with inhibitory or stimulatory substances. Additionally, this assay can be expanded beyond T cell signaling to any adhesive leukocyte population and any integrin-adhesion molecule pair. PMID:27404581

  1. Impairment of the Peritoneal Surface as a Decisive Factor for Intestinal Adhesions in Intraperitoneal Onlay Mesh Surgery - Introducing a New Rat Model

    PubMed Central

    Winny, M; Grethe, L; Maegel, L; Jonigk, D; Lippmann, T; Klempnauer, J; Poehnert, D

    2016-01-01

    Background: Meshes implanted intraperitoneally are known to cause adhesions potentially resulting in complications such as chronic pain, enterocutaneous fistula, or mesh infection. This study introduces a model for investigation of intestine-to-mesh adhesions and evaluates as to whether missing of visceral peritoneum is causative. Methods: In 18 rats, rectangular 1.5 x 2 cm patches of an uncoated polypropylene mesh (Ultrapro®) were sewn to the inner abdominal wall next to the cecum. Additionally, a meso-suture ensured contact between cecum and mesh. Rats were assigned to 2 groups: in 8 rats the peritoneum was left intact, in 10 the cecum was depleted from peritoneum with abrasion. Sacrifice was on day 7. Macroscopic evaluation used two adhesion scores. Specimens were evaluated microscopically, statistical analyses employed student's t-test. Results: On day 7, rats with mesh implantation combined with locally de-peritonealization by cecal abrasion mostly showed severe cecum-to-mesh agglutination (mean Lauder score 92%, mean total Hoffmann score 90%), whereas meshes of most animals without cecal abrasion only had some coverage with intraabdominal fat (33%, 24%; p = 0.0002). Histological work-up showed adequate wall ingrowth of mesh in all rats. In animals with cecal abrasion, meshes were mostly adhesive with cecal wall. However, when the peritoneum of cecum was unimpaired, abdominal wall above the mesh as well as cecum usually revealed sub-peritoneal tissue and a mono-layer cell coverage as seen in normal peritoneum. Conclusion: This study introduces a model mimicking a clinical situation of e.g. hernia repair by intraperitoneally implanted meshes when mesh has contact with normal and with de-peritonealized intestine. The model might be useful for testing mesh types and coatings as well as other devices for their efficacy in adhesion prevention. The high adhesion scores of rats with local de-peritonealization compared with the low scores of animals with intact

  2. Abdominal bloating: pathophysiology and treatment.

    PubMed

    Seo, A Young; Kim, Nayoung; Oh, Dong Hyun

    2013-10-01

    Abdominal bloating is a very common and troublesome symptom of all ages, but it has not been fully understood to date. Bloating is usually associated with functional gastrointestinal disorders or organic diseases, but it may also appear alone. The pathophysiology of bloating remains ambiguous, although some evidences support the potential mechanisms, including gut hypersensitivity, impaired gas handling, altered gut microbiota, and abnormal abdominal-phrenic reflexes. Owing to the insufficient understanding of these mechanisms, the available therapeutic options are limited. However, medical treatment with some prokinetics, rifaximin, lubiprostone and linaclotide could be considered in the treatment of bloating. In addition, dietary intervention is important in relieving symptom in patients with bloating. PMID:24199004

  3. Abdominal pain with a twist

    PubMed Central

    2011-01-01

    Malrotation in children is due to either an incomplete or non-rotation of the foetal mid-gut during perinatal development. Presentation is usually in the first few weeks of life, often with life-threatening volvulus and ischaemia. However, it can be a rare cause of abdominal pain in older children and young adults. We present such a case, as a reminder to emergency physicians that malrotation should be considered in the differential diagnosis of recurrent or chronic abdominal pain not only in children but also in adolescents. PMID:21635723

  4. Ultrasonographic diagnosis in abdominal tuberculosis.

    PubMed

    Sheikh, M; Moosa, I; Hussein, F M; Qurttom, M A; Behbehani, A I

    1999-05-01

    Sonographic findings were retrospectively analysed in 39 patients with proven abdominal tuberculosis (TB). The patients were treated over 15 years at a major teaching hospital, Mubarak Al-Kabber Hospital, in Kuwait. The findings included clear or complex ascites with fine strands, loculations and debris. The other findings were lymphadenopathy, bowel wall thickening, omental mass, focal lesions in the liver and spleen and psoas abscess. The sonographic findings in abdominal TB are not specific but may give valuable information to prevent unnecessary laparotomy. PMID:10901897

  5. Recurrent abdominal pain in children.

    PubMed

    Buch, Niyaz A; Ahmad, Sheikh Mushtaq; Ahmed, S Zubair; Ali, Syed Wazid; Charoo, B A; Hassan, Masood Ul

    2002-09-01

    Eighty five children with recurrent abdominal pain(RAP) were studied. Organic cause was noticed in 70 cases and non-organic in 15 cases. Giardiasis was the commonest organic cause in 57 (67.0 percent), either alone or with other parasitic infestations. Other organic causes include gallstones (4.7 percent), urinary infections (4.7 percent), esophagitis/gastritis (3.5 percent) and abdominal tuberculosis (2.3 percent). Single parent, school phobia, sibling rivalry, RAP in other family members and nocturnal enuresis are significant factors associated with nonorganic causes PMID:12368527

  6. Secondary abdominal appendicular ectopic pregnancy.

    PubMed

    Nama, Vivek; Gyampoh, Bright; Karoshi, Mahantesh; McRae, Reynold; Opemuyi, Isaac

    2007-01-01

    Although the case fatality rate for ectopic pregnancies has decreased to 0.08% in industrialized countries, it still represents 3.8% of maternal mortality in the United States alone. In developing countries, the case fatality rate varies from 3% to 27%. Laparoscopic management of tubal pregnancies is now the standard form of treatment where this technology is available. Abdominal pregnancies are rare, and secondary implantation of tubal ectopic pregnancies is the most common cause of abdominal gestations. We present an interesting case of secondary implantation of a tubal ectopic pregnancy to highlight the appendix as a possible secondary implantation site after a tubal ectopic pregnancy. PMID:17630175

  7. CD81 is essential for the formation of membrane protrusions and regulates Rac1-activation in adhesion-dependent immune cell migration.

    PubMed

    Quast, Thomas; Eppler, Felix; Semmling, Verena; Schild, Cora; Homsi, Yahya; Levy, Shoshana; Lang, Thorsten; Kurts, Christian; Kolanus, Waldemar

    2011-08-18

    CD81 (TAPA-1) is a member of the widely expressed and evolutionary conserved tetraspanin family that forms complexes with a variety of other cell surface receptors and facilitates hepatitis C virus entry. Here, we show that CD81 is specifically required for the formation of lamellipodia in migrating dendritic cells (DCs). Mouse CD81(-/-) DCs, or murine and human CD81 RNA interference knockdown DCs lacked the ability to form actin protrusions, thereby impairing their motility dramatically. Moreover, we observed a selective loss of Rac1 activity in the absence of CD81, the latter of which is exclusively required for integrin-dependent migration on 2-dimensional substrates. Neither integrin affinity for substrate nor the size of basal integrin clusters was affected by CD81 deficiency in adherent DCs. However, the use of total internal reflection fluorescence microscopy revealed an accumulation of integrin clusters above the basal layer in CD81 knockdown cells. Furthermore, β1- or β2-integrins, actin, and Rac are strongly colocalized at the leading edge of DCs, but the very fronts of these cells protrude CD81-containing membranes that project outward from the actin-integrin area. Taken together, these data suggest a thus far unappreciated role for CD81 in the mobilization of preformed integrin clusters into the leading edge of migratory DCs on 2-dimensional surfaces. PMID:21677313

  8. Running barbed suture quilting reduces abdominal drainage in perforator-based breast reconstruction.

    PubMed

    Liang, D G; Dusseldorp, J R; van Schalkwyk, C; Hariswamy, S; Wood, S; Rose, V; Moradi, P

    2016-01-01

    Prolonged abdominal drainage after perforator-based breast reconstruction is a common problem that can result in seroma formation, patient morbidity, and increased duration of hospital stay. Abdominal quilting with progressive tension sutures has been effective in reducing abdominal drainage in abdominoplasty patients prompting a change of practice in our unit. We studied consecutive unilateral mastectomy patients undergoing breast reconstruction with a deep inferior epigastric artery perforator (DIEP) flap. The initial 27 patients underwent breast reconstruction without any form of abdominal flap plication. The subsequent 26 patients underwent an identical DIEP flap raise procedure after which the abdominal flap was progressively tensioned using a running barbed suture quilting technique. All patients had closed suction drains inserted bilaterally until daily drain output was <40 ml in 2 consecutive days. Primary outcome measures were total volume of abdominal drainage and length of hospital stay. Independent statistical analyses were performed using Welch's t-test. There were no demographic differences between the two groups. A statistically significant decrease in the mean total abdominal drainage was found after quilting (238 ml vs. 528 ml; p = 0.0005). Patients in the quilting group also showed a reduction in mean duration of hospital stay. Quilting of the abdominal flap helps to reduce abdominal drainage not only in abdominoplasty patients but also in patients undergoing breast reconstruction with DIEP flap. PMID:26601878

  9. Does lining polypropylene with polyglactin mesh reduce intraperitoneal adhesions?

    PubMed

    Dasika, U K; Widmann, W D

    1998-09-01

    A method that appears to reduce the rate of adhesion formation between intraperitoneal viscera and prosthetic mesh is the placement of absorbable mesh between nonabsorbable mesh and intraperitoneal viscera. In this study, polyglactin mesh was compared with nonabsorbable polypropylene mesh (Marlex). Forty-seven Sprague-Dawley rats were divided into four groups: 1) control, 2) polyglactin (Vicryl), 3) polypropylene mesh, and 4) polyglactin-lined polypropylene mesh. All rats that underwent mesh placement had midline laparotomy with anastamosis of mesh to fascial borders. Controls underwent midline laparotomy and closure only. Groups were then studied at 1, 2, and 3 months, respectively, to determine the degree of adhesion formation. Gross inspection was performed by a blinded researcher with numerical rank given based on the number of adhesions observed: 0, none; 1, mild; 2, moderate; and 3, severe. The data showed that rats in group 3 (polypropylene only) had significant adhesions at 3 months, with average numerical score of 2.75. Polyglactin and polyglactin/polypropylene groups had similar scores of 1.5 each. Control groups predictably showed little adhesion formation, with average score of 0.25. Based on these data, it is observed that lining polypropylene mesh with absorbable polyglactin mesh can reduce adhesion formation to nonabsorbable mesh. The difference in degree of adhesions is most notable at 3 months. This technique may be an important adjunct to reduce the clinical sequelae of intraperitoneal adhesions. PMID:9731806

  10. Abdominal pain - children under age 12

    MedlinePlus

    Stomach pain in children; Pain - abdomen - children; Abdominal cramps in children; Belly ache in children ... When your child complains of abdominal pain, see if they can describe it to you. Here are different kinds of pain: ...

  11. Use of cyanoacrylate adhesives in general surgery.

    PubMed

    García Cerdá, David; Ballester, Antonio Martín; Aliena-Valero, Alicia; Carabén-Redaño, Anna; Lloris, José M

    2015-08-01

    This paper presents a review of the use of cyanoacrylate adhesives (CA) in general surgery and digestive surgery, studies the mechanisms of action and interactions of CAs in adherent tissues, and compiles data on the latest experimental and clinical applications. More than seven million traumatic injuries are estimated to occur every year, and between 26 and 90 million surgical procedures using different techniques are performed to close the resulting wounds. Traditional methods not only are both useful and effective, but also have some drawbacks. This review covers a considerable number of surgical procedures for which CAs had satisfactory results. The adhesive facilitated the healing of very diverse tissues, such as solid organs, vascular tissue or the abdominal wall. In other cases, no significant differences were found when CA was compared to traditional methods, with the adhesive standing out as a simple and reliable solution. The number of procedures in which CA was detrimental was very low. This review also collects and describes these. In conclusion, the surgical fields and procedures in which CA was successfully used are highly diverse. This review will allow physicians to determine which techniques were first used experimentally, but finally settled in clinical practice as feasible alternatives to standard treatments. PMID:25344231

  12. Bistability of Cell Adhesion in Shear Flow

    PubMed Central

    Efremov, Artem; Cao, Jianshu

    2011-01-01

    Cell adhesion plays a central role in multicellular organisms helping to maintain their integrity and homeostasis. This complex process involves many different types of adhesion proteins, and synergetic behavior of these proteins during cell adhesion is frequently observed in experiments. A well-known example is the cooperation of rolling and stationary adhesion proteins during the leukocytes extravasation. Despite the fact that such cooperation is vital for proper functioning of the immune system, its origin is not fully understood. In this study we constructed a simple analytic model of the interaction between a leukocyte and the blood vessel wall in shear flow. The model predicts existence of cell adhesion bistability, which results from a tug-of-war between two kinetic processes taking place in the cell-wall contact area—bond formation and rupture. Based on the model results, we suggest an interpretation of several cytoadhesion experiments and propose a simple explanation of the existing synergy between rolling and stationary adhesion proteins, which is vital for effective cell adherence to the blood vessel walls in living organisms. PMID:21889439

  13. Cytotoxicity of denture adhesives.

    PubMed

    de Gomes, Pedro Sousa; Figueiral, Maria Helena; Fernandes, Maria Helena R; Scully, Crispian

    2011-12-01

    Ten commercially available denture adhesives, nine soluble formulations (six creams, three powders) and one insoluble product (pad), were analyzed regarding the cytotoxicity profile in direct and indirect assays using L929 fibroblast cells. In the direct assay, fibroblasts were seeded over the surface of a thick adhesive gel (5%, creams; 2.5%, powders and pad). In the indirect assay, cells were cultured in the presence of adhesive extracts prepared in static and dynamic conditions (0.5-2%, creams; 0.25-1%, powders and pad). Cell toxicity was assessed for cell viability/proliferation (MTT assay) and cell morphology (observation of the F-actin cytoskeleton organization by confocal laser scanning microscopy). Direct contact of the L929 fibroblasts with the thick adhesive gels caused no, or only a slight, decrease in cell viability/proliferation. The adhesive extracts (especially those prepared in dynamic conditions) caused significantly higher growth inhibition of fibroblasts and, in addition, caused dose- and time-dependent effects, throughout the 6-72 h exposure time. Also, dose-dependent effects on cell morphology, with evident disruption of the F-actin cytoskeleton organization, were seen in the presence of most adhesives. In conclusion, the adhesives possessed different degrees of cytotoxicity, but similar dose- and time-dependent biological profiles. PMID:20844908

  14. A comparison of prosthetic materials used to repair abdominal wall defects.

    PubMed

    Mori, N; Takano, K; Miyake, T; Nishio, T; Muto, S; Koshizuka, K; Nakagomi, H; Kubo, M; Tada, Y

    1998-09-01

    Large abdominal wall defects may require a prosthesis for closure. The aim of our study was to identify the best material for abdominoplasty in pediatric patients. One hundred twenty-eight Wistar KY strain male rats (3 weeks old) were used. All animals underwent celiotomy via a midline skin incision. They were divided into seven groups as follows: the animals in groups 1 through 6 underwent full-thickness abdominal wall excision 3 cm in diameter. The animals in group 1 underwent primary closure. In groups 2 through 6 the defect was closed with prosthetic material. In Group 7, a sham operation was performed. Daily weights were measured. The animals were killed after 3 and 9 weeks. Adhesion scores were assigned for each group. Vicryl mesh resulted in the fewest adhesions and had no effect on weight gain in the developing rats. PMID:9716675

  15. Relationships between water wettability and ice adhesion.

    PubMed

    Meuler, Adam J; Smith, J David; Varanasi, Kripa K; Mabry, Joseph M; McKinley, Gareth H; Cohen, Robert E

    2010-11-01

    Ice formation and accretion may hinder the operation of many systems critical to national infrastructure, including airplanes, power lines, windmills, ships, and telecommunications equipment. Yet despite the pervasiveness of the icing problem, the fundamentals of ice adhesion have received relatively little attention in the scientific literature and it is not widely understood which attributes must be tuned to systematically design "icephobic" surfaces that are resistant to icing. Here we probe the relationships between advancing/receding water contact angles and the strength of ice adhesion to bare steel and twenty-one different test coatings (∼200-300 nm thick) applied to the nominally smooth steel discs. Contact angles are measured using a commercially available goniometer, whereas the average strengths of ice adhesion are evaluated with a custom-built laboratory-scale adhesion apparatus. The coatings investigated comprise commercially available polymers and fluorinated polyhedral oligomeric silsesquioxane (fluorodecyl POSS), a low-surface-energy additive known to enhance liquid repellency. Ice adhesion strength correlates strongly with the practical work of adhesion required to remove a liquid water drop from each test surface (i.e., with the quantity [1 + cos θ(rec)]), and the average strength of ice adhesion was reduced by as much as a factor of 4.2 when bare steel discs were coated with fluorodecyl POSS-containing materials. We argue that any further appreciable reduction in ice adhesion strength will require textured surfaces, as no known materials exhibit receding water contact angles on smooth/flat surfaces that are significantly above those reported here (i.e., the values of [1 + cos θ(rec)] reported here have essentially reached a minimum for known materials). PMID:20949900

  16. Cell adhesion force microscopy

    PubMed Central

    Sagvolden, G.; Giaever, I.; Pettersen, E. O.; Feder, J.

    1999-01-01

    The adhesion forces of cervical carcinoma cells in tissue culture were measured by using the manipulation force microscope, a novel atomic force microscope. The forces were studied as a function of time and temperature for cells cultured on hydrophilic and hydrophobic polystyrene substrates with preadsorbed proteins. The cells attached faster and stronger at 37°C than at 23°C and better on hydrophilic than on hydrophobic substrates, even though proteins adsorb much better to the hydrophobic substrates. Because cell adhesion serves to control several stages in the cell cycle, we anticipate that the manipulation force microscope can help clarify some cell-adhesion related issues. PMID:9892657

  17. Adhesive Contact Sweeper

    NASA Technical Reports Server (NTRS)

    Patterson, Jonathan D.

    1993-01-01

    Adhesive contact sweeper removes hair and particles vacuum cleaner leaves behind, without stirring up dust. Also cleans loose rugs. Sweeper holds commercially available spools of inverted adhesive tape. Suitable for use in environments in which air kept free of dust; optics laboratories, computer rooms, and areas inhabited by people allergic to dust. For carpets, best used in tandem with vacuum cleaner; first pass with vacuum cleaner removes coarse particles, and second pass with sweeper extracts fine particles. This practice extends useful life of adhesive spools.

  18. Significance of bacterial flora in abdominal irradiation-induced inhibition of lung metastases

    SciTech Connect

    Matsumoto, T.; Ando, K.; Koike, S.

    1988-06-01

    We have previously reported that abdominal irradiation prior to i.v. injection of syngeneic tumor cells reduced metastases in lung. Our report described an investigation of the significance of intestinal organisms in the radiation effect. We found that eliminating intestinal organisms with antibiotics totally abolished the radiation effect. Monoassociation of germ-free mice revealed that the radiation effect was observable only for Enterobacter cloacae, never for Streptococcus faecium, Bifidobacterium adlesentis, or Escherichia coli. After abdominal irradiation of regular mice, E. cloacae multiplied in cecal contents, adhered to mucous membranes, invaded the cecal wall, and translocated to mesenteric lymph nodes. Intravenous administration of E. cloacae in place of abdominal irradiation inhibited metastases. E. cloacae-monoassociated mice developed fewer metastases than germ-free mice, and the reduction was further enhanced by abdominal irradiation. We concluded that abdominal irradiation caused the invasion of E. cloacae from the mucous membrane of the intestine and inhibited formation of lung metastases.

  19. 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

  20. 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

  1. Abdominal Distension and Vascular Collapse.

    PubMed

    Cosentino, Gina; Uwaifo, Gabriel I

    2016-04-01

    We present the case of a 43-year-old gentleman who presented to the emergency room with acute abdominal distension, confusion and vascular collapse. The emergent radiologic imaging obtained showed massive bilateral adrenal enlargement, but despite the initial clinical suspicion of possible overwhelming sepsis and/or massive abdominal/intralesional hemorrhage, lab tests based obtained rapidly confirmed the diagnosis of acute Addisonian crisis which responded dramatically to adrenocorticoid hormone replacement therapy and aggressive fluid resuscitation. The patient's established history of metastatic lung cancer confirmed this as a case of metastatic massive bilateral adrenal metastases with an initial presentation of acute adrenal insufficiency which is uncommon in the setting of metastatic carcinomatosis but more typically associated with lymphomas. Recognition of this clinical possibility is vital to enable rapid diagnosis and consequent life saving therapy. PMID:27328473

  2. [Abdominal bruit associated with hypertension].

    PubMed

    Fontseré, N; Bonet, J; Bonal, J; Romero, R

    2004-01-01

    First cause of secondary hypertension is renovascular hypertension which presents abdominal bruit in 16 to 20% of cases. This clinical sign is also associated with other vascular disease of the abdomen such as celiac trunk stenosis and/or aneurysms located on the pancreaticoduodenal or gastroduodenal arcs level, with little representation among aneurysm. They usually appear on a context of digestive complications like neoplasias, chronic pancreatitis or gastric obstructions possibly with obstructive icterus, hemorrhage and acute abdomen episodes. Its presentation in other contexts is rare and constitutes a diagnostic challenge. Diagnosis is made by abdominal arteriography which is the best method because you can locate the problem as well as intervene therapeutically with embolization of the aneurysme. We would like to emphasize the importance of a quick diagnosis due to the risk of rupture and the high morbi-mortality associated. PMID:15219082

  3. Optical adhesive property study

    SciTech Connect

    Sundvold, P.D.

    1996-01-01

    Tests were performed to characterize the mechanical and thermal properties of selected optical adhesives to identify the most likely candidate which could survive the operating environment of the Direct Optical Initiation (DOI) program. The DOI system consists of a high power laser and an optical module used to split the beam into a number of channels to initiate the system. The DOI requirements are for a high shock environment which current military optical systems do not operate. Five candidate adhesives were selected and evaluated using standardized test methods to determine the adhesives` physical properties. EC2216, manufactured by 3M, was selected as the baseline candidate adhesive based on the test results of the physical properties.

  4. Adhesives for Aerospace

    NASA Technical Reports Server (NTRS)

    Meade, L. E.

    1985-01-01

    The industry is hereby challenged to integrate adhesive technology with the total structure requirements in light of today's drive into automation/mechanization. The state of the art of adhesive technology is fairly well meeting the needs of the structural designers, the processing engineer, and the inspector, each on an individual basis. The total integration of these needs into the factory of the future is the next collective hurdle to be achieved. Improved processing parameters to fit the needs of automation/mechanization will necessitate some changes in the adhesive forms, formulations, and chemistries. Adhesives have, for the most part, kept up with the needs of the aerospace industry, normally leading the rest of the industry in developments. The wants of the aerospace industry still present a challenge to encompass all elements, achieving a totally integrated joined and sealed structural system. Better toughness with hot-wet strength improvements is desired. Lower cure temperatures, longer out times, and improved corrosion inhibition are desired.

  5. Adhesion of Lunar Dust

    NASA Astrophysics Data System (ADS)

    Walton, Otis R.

    2007-04-01

    This paper reviews the physical characteristics of lunar dust and the effects of various fundamental forces acting on dust particles on surfaces in a lunar environment. There are transport forces and adhesion forces after contact. Mechanical forces (i.e., from rover wheels, astronaut boots and rocket engine blast) and static electric effects (from UV photo-ionization and/or tribo-electric charging) are likely to be the major contributors to the transport of dust particles. If fine regolith particles are deposited on a surface, then surface energy-related (e.g., van der Walls) adhesion forces and static-electric-image forces are likely to be the strongest contributors to adhesion. Some measurement techniques are offered to quantify the strength of adhesion forces. And finally some dust removal techniques are discussed.

  6. Adhesion of Lunar Dust

    NASA Technical Reports Server (NTRS)

    Walton, Otis R.

    2007-01-01

    This paper reviews the physical characteristics of lunar dust and the effects of various fundamental forces acting on dust particles on surfaces in a lunar environment. There are transport forces and adhesion forces after contact. Mechanical forces (i.e., from rover wheels, astronaut boots and rocket engine blast) and static electric effects (from UV photo-ionization and/or tribo-electric charging) are likely to be the major contributors to the transport of dust particles. If fine regolith particles are deposited on a surface, then surface energy-related (e.g., van der Walls) adhesion forces and static-electric-image forces are likely to be the strongest contributors to adhesion. Some measurement techniques are offered to quantify the strength of adhesion forces. And finally some dust removal techniques are discussed.

  7. Leucocyte cellular adhesion molecules.

    PubMed

    Yong, K; Khwaja, A

    1990-12-01

    Leucocytes express adhesion promoting receptors which mediate cell-cell and cell-matrix interactions. These adhesive interactions are crucial to the regulation of haemopoiesis and thymocyte maturation, the direction and control of leucocyte traffic and migration through tissues, and in the development of immune and non-immune inflammatory responses. Several families of adhesion receptors have been identified (Table). The leucocyte integrin family comprises 3 alpha beta heterodimeric membrane glycoproteins which share a common beta subunit, designated CD18. The alpha subunits of each of the 3 members, lymphocyte function associated antigen-1 (LFA-1), macrophage antigen-1 (Mac-1) and p150,95 are designated CD11a, b and c respectively. These adhesion molecules play a critical part in the immune and inflammatory responses of leucocytes. The leucocyte integrin family is, in turn, part of the integrin superfamily, members of which are evolutionally, structurally and functionally related. Another Integrin subfamily found on leucocytes is the VLA group, so-called because the 'very late activation antigens' VLA-1 and VLA-2 were originally found to appear late in T-cell activation. Members of this family function mainly as extracellular matrix adhesion receptors and are found both on haemopoietic and non-haemopoietic cells. They play a part in diverse cellular functions including tissue organisation, lymphocyte recirculation and T-cell immune responses. A third integrin subfamily, the cytoadhesins, are receptors on platelets and endothelial cells which bind extracellular matrix proteins. A second family of adhesion receptors is the immunoglobulin superfamily, members of which include CD2, LFA-3 and ICAM-1, which participate in T-cell adhesive interactions, and the antigen-specific receptors of T and B cells, CD4, CD8 and the MHC Class I and II molecules. A recently recognised family of adhesion receptors is the selectins, characterised by a common lectin domain. Leucocyte

  8. Management of voluminous abdominal incisional hernia.

    PubMed

    Bouillot, J-L; Poghosyan, T; Pogoshian, T; Corigliano, N; Canard, G; Veyrie, N

    2012-10-01

    Incisional hernia is one of the classic complications after abdominal surgery. The chronic, gradual increase in size of some of these hernias is such that the hernia ring widens to a point where there is a loss of substance in the abdominal wall, herniated organs can become incarcerated or strangulated while poor abdominal motility can alter respiratory function. The surgical treatment of small (<5 cm) incisional hernias is safe and straightforward, by either laparotomy or laparoscopy. For large hernias, surgical repair is often difficult. After reintegration of herniated viscera into the abdominal cavity, the abdominal wall defect must be closed anatomically in order to restore the function to the abdominal wall. Prosthetic reinforcement of the abdominal wall is mandatory for long-term successful repair. There are multiple techniques for prosthetic hernia repair, but placement of Dacron mesh in the retromuscular plane is our preference. PMID:23137643

  9. LIM-kinase 2 induces formation of stress fibres, focal adhesions and membrane blebs, dependent on its activation by Rho-associated kinase-catalysed phosphorylation at threonine-505.

    PubMed Central

    Amano, T; Tanabe, K; Eto, T; Narumiya, S; Mizuno, K

    2001-01-01

    LIM-kinase 1 and 2 (LIMK1 and LIMK2) phosphorylate cofilin and induce actin cytoskeletal reorganization. LIMK1 is activated by Rho-associated, coiled-coil-forming protein kinase (ROCK) and p21-activated kinase 1 (PAK1), but activation mechanisms and cellular functions of LIMK2 have remained to be determined. We report here that LIMK1 and LIMK2 phosphorylate both cofilin and actin-depolymerizing factor (ADF) specifically at Ser-3 and exhibit partially distinct substrate specificity when tested using site-directed cofilin mutants as substrates. We also show that LIMK2 is activated by ROCK by phosphorylation at Thr-505 within the activation loop. Wild-type LIMK2, but not its mutant (T505V) with replacement of Thr-505 by Val, was activated by ROCK in vitro and in vivo. LIMK2 mutants with replacement of Thr-505 by one or two Glu residues (T505E or T505EE) increased the kinase activity about 3.6-fold but were not further activated by ROCK. When expressed in HeLa cells, wild-type LIMK2, but not the T505V mutant, induced the formation of stress fibres, focal adhesions and membrane blebs. Furthermore, inhibitors of Rho and ROCK significantly suppressed LIMK2-induced stress fibres and membrane blebs. These results suggest that LIMK2 functions downstream of the Rho-ROCK signalling pathway and plays a role in reorganization of actin filaments and membrane structures, by phosphorylating cofilin/ADF proteins. PMID:11171090

  10. High temperature adhesives

    NASA Technical Reports Server (NTRS)

    St.clair, Terry L.

    1991-01-01

    The aerospace and electronics industries have an ever increasing need for higher performance materials. In recent years, linear aromatic polyimides have been proven to be a superior class of materials for various applications in these industries. The use of this class of polymers as adhesives is continuing to increase. Several NASA Langley developed polyimides show considerable promise as adhesives because of their high glass transition temperatures, thermal stability, resistance to solvents/water, and their potential for cost effective manufacture.

  11. Acute Abdominal Pain in Children.

    PubMed

    Reust, Carin E; Williams, Amy

    2016-05-15

    Acute abdominal pain accounts for approximately 9% of childhood primary care office visits. Symptoms and signs that increase the likelihood of a surgical cause for pain include fever, bilious vomiting, bloody diarrhea, absent bowel sounds, voluntary guarding, rigidity, and rebound tenderness. The age of the child can help focus the differential diagnosis. In infants and toddlers, clinicians should consider congenital anomalies and other causes, including malrotation, hernias, Meckel diverticulum, or intussusception. In school-aged children, constipation and infectious causes of pain, such as gastroenteritis, colitis, respiratory infections, and urinary tract infections, are more common. In female adolescents, clinicians should consider pelvic inflammatory disease, pregnancy, ruptured ovarian cysts, or ovarian torsion. Initial laboratory tests include complete blood count, erythrocyte sedimentation rate or C-reactive protein, urinalysis, and a pregnancy test. Abdominal radiography can be used to diagnose constipation or obstruction. Ultrasonography is the initial choice in children for the diagnosis of cholecystitis, pancreatitis, ovarian cyst, ovarian or testicular torsion, pelvic inflammatory disease, pregnancy-related pathology, and appendicitis. Appendicitis is the most common cause of acute abdominal pain requiring surgery, with a peak incidence during adolescence. When the appendix is not clearly visible on ultrasonography, computed tomography or magnetic resonance imaging can be used to confirm the diagnosis. PMID:27175718

  12. Nascent Integrin Adhesions Form on All Matrix Rigidities after Integrin Activation.

    PubMed

    Changede, Rishita; Xu, Xiaochun; Margadant, Felix; Sheetz, Michael P

    2015-12-01

    Integrin adhesions assemble and mature in response to ligand binding and mechanical factors, but the molecular-level organization is not known. We report that ∼100-nm clusters of ∼50 β3-activated integrins form very early adhesions under a wide variety of conditions on RGD surfaces. These adhesions form similarly on fluid and rigid substrates, but most adhesions are transient on rigid substrates. Without talin or actin polymerization, few early adhesions form, but expression of either the talin head or rod domain in talin-depleted cells restores early adhesion formation. Mutation of the integrin binding site in the talin rod decreases cluster size. We suggest that the integrin clusters constitute universal early adhesions and that they are the modular units of cell matrix adhesions. They require the association of activated integrins with cytoplasmic proteins, in particular talin and actin, and cytoskeletal contraction on them causes adhesion maturation for cell motility and growth. PMID:26625956

  13. Genetic Architecture of Abdominal Pigmentation in Drosophila melanogaster

    PubMed Central

    Dembeck, Lauren M.; Huang, Wen; Magwire, Michael M.; Lawrence, Faye; Lyman, Richard F.; Mackay, Trudy F. C.

    2015-01-01

    Pigmentation varies within and between species and is often adaptive. The amount of pigmentation on the abdomen of Drosophila melanogaster is a relatively simple morphological trait, which serves as a model for mapping the genetic basis of variation in complex phenotypes. Here, we assessed natural variation in female abdominal pigmentation in 175 sequenced inbred lines of the Drosophila melanogaster Genetic Reference Panel, derived from the Raleigh, NC population. We quantified the proportion of melanization on the two most posterior abdominal segments, tergites 5 and 6 (T5, T6). We found significant genetic variation in the proportion of melanization and high broad-sense heritabilities for each tergite. Genome-wide association studies identified over 150 DNA variants associated with the proportion of melanization on T5 (84), T6 (34), and the difference between T5 and T6 (35). Several of the top variants associated with variation in pigmentation are in tan, ebony, and bric-a-brac1, genes known to affect D. melanogaster abdominal pigmentation. Mutational analyses and targeted RNAi-knockdown showed that 17 out of 28 (61%) novel candidate genes implicated by the genome-wide association study affected abdominal pigmentation. Several of these genes are involved in developmental and regulatory pathways, chitin production, cuticle structure, and vesicle formation and transport. These findings show that genetic variation may affect multiple steps in pathways involved in tergite development and melanization. Variation in these novel candidates may serve as targets for adaptive evolution and sexual selection in D. melanogaster. PMID:25933381

  14. 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. PMID:27488250

  15. Flexibilized copolyimide adhesives

    NASA Technical Reports Server (NTRS)

    Progar, Donald J.; St.clair, Terry L.

    1988-01-01

    Two copolyimides, LARC-STPI and STPI-LARC-2, with flexible backbones were processed and characterized as adhesives. The processability and adhesive properties were compared to those of a commercially available form of LARC-TPI. Lap shear specimens were fabricated using adhesive tape prepared from each of the three polymers. Lap shear tests were performed at room temperature, 177 C, and 204 C before and after exposure to water-boil and to thermal aging at 204 C for up to 1000 hours. The three adhesive systems possess exceptional lap shear strengths at room temperature and elevated temperatures both before and after thermal exposure. LARC-STPI, because of its high glass transition temperature provided high lap shear strengths up to 260 C. After water-boil, LARC-TPI exhibited the highest lap shear strengths at room temperature and 177 C, whereas the LARC-STPI retained a higher percentage of its original strength when tested at 204 C. These flexible thermoplastic copolyimides show considerable potential as adhesives based on this study and because of the ease of preparation with low cost, commercially available materials.

  16. Platelet Adhesion under Flow

    PubMed Central

    Ruggeri, Zaverio M.

    2011-01-01

    Platelet adhesive mechanisms play a well-defined role in hemostasis and thrombosis, but evidence continues to emerge for a relevant contribution to other pathophysiological processes including inflammation, immune-mediated responses to microbial and viral pathogens, and cancer metastasis. Hemostasis and thrombosis are related aspects of the response to vascular injury, but the former protects from bleeding after trauma while the latter is a disease mechanism. In either situation, adhesive interactions mediated by specific membrane receptors support the initial attachment of single platelets to cellular and extracellular matrix constituents of the vessel wall and tissues. In the subsequent steps of thrombus growth and stabilization, adhesive interactions mediate platelet to platelet cohesion (aggregation) and anchoring to the fibrin clot. A key functional aspect of platelets is their ability to circulate in a quiescent state surveying the integrity of the inner vascular surface, coupled to a prompt reaction wherever alterations are detected. In many respects, therefore, platelet adhesion to vascular wall structures, to one another or to other blood cells are facets of the same fundamental biological process. The adaptation of platelet adhesive functions to the effects of blood flow is the main focus of this review. PMID:19191170

  17. Epithelial Cell Adhesion Molecule

    PubMed Central

    Trzpis, Monika; McLaughlin, Pamela M.J.; de Leij, Lou M.F.H.; Harmsen, Martin C.

    2007-01-01

    The epithelial cell adhesion molecule (EpCAM, CD326) is a glycoprotein of ∼40 kd that was originally identified as a marker for carcinoma, attributable to its high expression on rapidly proliferating tumors of epithelial origin. Normal epithelia express EpCAM at a variable but generally lower level than carcinoma cells. In early studies, EpCAM was proposed to be a cell-cell adhesion molecule. However, recent insights revealed a more versatile role for EpCAM that is not limited only to cell adhesion but includes diverse processes such as signaling, cell migration, proliferation, and differentiation. Cell surface expression of EpCAM may actually prevent cell-cell adhesion. Here, we provide a comprehensive review of the current knowledge on EpCAM biology in relation to other cell adhesion molecules. We discuss the implications of the newly identified functions of EpCAM in view of its prognostic relevance in carcinoma, inflammatory pathophysiology, and tissue development and regeneration as well as its role in normal epithelial homeostasis. PMID:17600130

  18. A Randomized, Multi-Center, Single Blind, Active-Controlled, Matched Pairs Clinical Study to Evaluate Prevention of Adhesion Formation and Safety of HyFence in Patients After Endoscopic Sinus Surgery

    PubMed Central

    Chang, Chul; Hong, Sung-Moon; Cho, Jin-Hee; Shim, Sang Yul; Cho, Jung-Sun

    2014-01-01

    Objectives Recurrent mucosal disease and anatomic obstruction are commonly cited causes of failed endoscopic sinus surgery (ESS). Hyaluronic acid (HA) has been reported to reduce scarring and to promote wound healing in sinonasal surgery. HyFence is HA stabilized by 1, 4-butandiol diglycidyl ether, which makes it less-water-soluble and highly viscoelastic. The purpose of this study is to examine the anti-adhesion effect of HyFence after ESS compared to that of HA-CMC (Guardix-Sol). Methods Seventy-four patients with chronic rhinosinusitis who underwent ESS were included in the study. After the ESS procedure, Merocel was placed in the ethmoidectomized areas of the both sides. Five milliliters of Guardix-Sol was then applied to the Merocel of one side and HyFence LV was applied to the other side. The effect of the agents was evaluated at one, two, and four weeks after surgery by endoscopic examination. The severity of adhesion, edema, infection and complications were evaluated. Results There was no significant difference in the incidence of postoperative adhesion between the HyFence group and the Guardix-Sol group (P>0.05). Mean postoperative grades of edema and infection showed no significant difference between groups (P>0.05). There was no significant postoperative complications associated with either anti-adhesion agent (P>0.05). Conclusion HyFence has equivalent anti-adhesion effect compared to Guardix-Sol following ESS. PMID:24587878

  19. Large Abdominal Wall Endometrioma Following Laparoscopic Hysterectomy

    PubMed Central

    Borncamp, Erik; Mehaffey, Philip; Rotman, Carlos

    2011-01-01

    Background: Endometriosis is a common condition in women that affects up to 45% of patients in the reproductive age group by causing pelvic pain. It is characterized by the presence of endometrial tissue outside the uterine cavity and is rarely found subcutaneously or in abdominal incisions, causing it to be overlooked in patients with abdominal pain. Methods: A 45-year-old woman presented with lower abdominal pain 2 years following a laparoscopic supracervical hysterectomy. She was found to have incidental cholelithiasis and a large abdominal mass suggestive of a significant ventral hernia on CT scan. Results: Due to the peculiar presentation, surgical intervention took place that revealed a large 9cm×7.6cm×6.2cm abdominal wall endometrioma. Conclusion: Although extrapelvic endometriosis is rare, it should be entertained in the differential diagnosis for the female patient who presents with an abdominal mass and pain and has a previous surgical history. PMID:21902990

  20. Blunt abdominal trauma in children.

    PubMed

    Tepas, J J

    1993-06-01

    The growing popularity of nonoperative treatment of children with splenic injuries has seduced some physicians into a false sense of security regarding care of the injured child. Although it has been established that hemodynamically stable children with splenic, hepatic, and even renal injuries can safely be treated "expectantly," this concept cannot be applied indiscriminately. Accurate diagnosis and effective care of the child with blunt abdominal trauma is an exercise of clinical precision that demands attention to detail and thorough evaluation. This review addresses this process in light of recent advances in diagnostic imaging and in consideration of recent reports analyzing different protocols for therapeutic decision making. PMID:8374651

  1. BIOMECHANICS OF ABDOMINAL AORTIC ANEURYSM

    PubMed Central

    Vorp, David A.

    2009-01-01

    Abdominal aortic aneurysm (AAA) is a condition whereby the terminal aorta permanently dilates to dangerous proportions, risking rupture. The biomechanics of AAA has been studied with great interest since aneurysm rupture is a mechanical failure of the degenerated aortic wall and is a significant cause of death in developed countries. In this review article, the importance of considering the biomechanics of AAA is discussed, and then the history and the state-of-the-art of this field is reviewed - including investigations into the biomechanical behavior of AAA tissues, modeling AAA wall stress and factors which influence it, and the potential clinical utility of these estimates in predicting AAA rupture. PMID:17254589

  2. [Abdominal pain, constipation and anemia].

    PubMed

    Barresi, Fabio; Kunz Caflish, Isabel; Bayly-Schinzel, Leena; Dressel, Holger

    2016-03-30

    We present the case of a 42-year old man who went to the emergency department because of spasmodic abdominal pain. The abdomen was soft. A gastroscopy and a colonoscopy were without pathological findings. The laboratory analyses indicated anemia. The differential blood count showed basophilic granules in the red blood cells. The blood lead level was elevated. A lead poisoning was diagnosed. The cause was the oral intake of an ayurvedic medication which the patient had received in Bangladesh to treat his vitiligo. PMID:27005735

  3. Different Anti-Contractile Function and Nitric Oxide Production of Thoracic and Abdominal Perivascular Adipose Tissues

    PubMed Central

    Victorio, Jamaira A.; Fontes, Milene T.; Rossoni, Luciana V.; Davel, Ana P.

    2016-01-01

    Divergent phenotypes between the perivascular adipose tissue (PVAT) surrounding the abdominal and the thoracic aorta might be implicated in regional aortic differences, such as susceptibility to atherosclerosis. Although PVAT of the thoracic aorta exhibits anti-contractile function, the role of PVAT in the regulation of the vascular tone of the abdominal aorta is not well defined. In the present study, we compared the anti-contractile function, nitric oxide (NO) availability, and reactive oxygen species (ROS) formation in PVAT and vessel walls of abdominal and thoracic aorta. Abdominal and thoracic aortic tissue from male Wistar rats were used to perform functional and molecular experiments. PVAT reduced the contraction evoked by phenylephrine in the absence and presence of endothelium in the thoracic aorta, whereas this anti-contractile effect was not observed in the abdominal aorta. Abdominal PVAT exhibited a reduction in endothelial NO synthase (eNOS) expression compared with thoracic PVAT, without differences in eNOS expression in the vessel walls. In agreement with this result, NO production evaluated in situ using 4,5-diaminofluorescein was less pronounced in abdominal compared with thoracic aortic PVAT, whereas no significant difference was observed for endothelial NO production. Moreover, NOS inhibition with L-NAME enhanced the phenylephrine-induced contraction in endothelial-denuded rings with PVAT from thoracic but not abdominal aorta. ROS formation and lipid peroxidation products evaluated through the quantification of hydroethidine fluorescence and 4-hydroxynonenal adducts, respectively, were similar between PVAT and vessel walls from the abdominal and thoracic aorta. Extracellular superoxide dismutase (SOD) expression was similar between the vessel walls and PVAT of the abdominal and thoracic aorta. However, Mn-SOD levels were reduced, while CuZn-SOD levels were increased in abdominal PVAT compared with thoracic aortic PVAT. In conclusion, our results

  4. Protein mediated membrane adhesion

    NASA Astrophysics Data System (ADS)

    Carlson, Andreas; Mahadevan, L.

    2015-05-01

    Adhesion in the context of mechanical attachment, signaling, and movement in cellular dynamics is mediated by the kinetic interactions between membrane-embedded proteins in an aqueous environment. Here, we present a minimal theoretical framework for the dynamics of membrane adhesion that accounts for the kinetics of protein binding, the elastic deformation of the membrane, and the hydrodynamics of squeeze flow in the membrane gap. We analyze the resulting equations using scaling estimates to characterize the spatiotemporal features of the adhesive patterning and corroborate them using numerical simulations. In addition to characterizing aspects of cellular dynamics, our results might also be applicable to a range of phenomena in physical chemistry and materials science where flow, deformation, and kinetics are coupled to each other in slender geometries.

  5. Adhesive particle shielding

    DOEpatents

    Klebanoff, Leonard Elliott; Rader, Daniel John; Walton, Christopher; Folta, James

    2009-01-06

    An efficient device for capturing fast moving particles has an adhesive particle shield that includes (i) a mounting panel and (ii) a film that is attached to the mounting panel wherein the outer surface of the film has an adhesive coating disposed thereon to capture particles contacting the outer surface. The shield can be employed to maintain a substantially particle free environment such as in photolithographic systems having critical surfaces, such as wafers, masks, and optics and in the tools used to make these components, that are sensitive to particle contamination. The shield can be portable to be positioned in hard-to-reach areas of a photolithography machine. The adhesive particle shield can incorporate cooling means to attract particles via the thermophoresis effect.

  6. Misfit effects in adhesion calculations

    NASA Astrophysics Data System (ADS)

    Schnitker, Jurgen; Srolovitz, David J.

    1998-03-01

    The work of adhesion of bimaterial interfaces is commonly computed using quantum mechanical methods in which the two materials are strained into coherency. There is no relaxation of the coherency by the formation of an array of interfacial misfit dislocations, contrary to what is commonly observed for essentially all systems other than very thin films. In this paper, we investigate the errors introduced into the work of adhesion associated with the assumption of coherency. Series of atomistic simulations in two and three dimensions are performed using a simple Lennard-Jones-type model potential. We demonstrate that the assumption of coherency introduces errors that increase rapidly with misfit (for small misfit) and can easily be of the order of several tens of percent. We trace the source of these errors to the neglect of the elastic fields of misfit dislocations and to the variation in the number of bonds per unit interfacial area with misfit when coherency is assumed. Suggestions are made to minimize and/or correct for this error.

  7. Rapid Development of Wet Adhesion between Carboxymethylcellulose Modified Cellulose Surfaces Laminated with Polyvinylamine Adhesive.

    PubMed

    Gustafsson, Emil; Pelton, Robert; Wågberg, Lars

    2016-09-14

    The surface of regenerated cellulose membranes was modified by irreversible adsorption of carboxymethylcellulose (CMC). Pairs of wet CMC-modified membranes were laminated with polyvinylamine (PVAm) at room temperature, and the delamination force for wet membranes was measured for both dried and never-dried laminates. The wet adhesion was studied as a function of PVAm molecular weight, amine content, and deposition pH of the polyelectrolyte. Surprisingly the PVAm-CMC system gave substantial wet adhesion that exceeded that of TEMPO-oxidized membranes with PVAm for both dried and never-dried laminates. The greatest wet adhesion was achieved for fully hydrolyzed high molecular weight PVAm. Bulk carboxymethylation of cellulose membranes gave inferior wet adhesion combined with PVAm as compared to CMC adsorption which indicates that a CMC layer of the order of 10 nm was necessary. There are no obvious covalent cross-linking reactions between CMC and PVAm at room temperature, and on the basis of our results, we are instead attributing the wet adhesion to complex formation between the PVAm and the irreversibly adsorbed CMC at the cellulose surface. We propose that interdigitation of PVAm chains into the CMC layer is responsible for the high wet adhesion values. PMID:27552256

  8. Periderm prevents pathological epithelial adhesions during embryogenesis

    PubMed Central

    Richardson, Rebecca J.; Hammond, Nigel L.; Coulombe, Pierre A.; Saloranta, Carola; Nousiainen, Heidi O.; Salonen, Riitta; Berry, Andrew; Hanley, Neil; Headon, Denis; Karikoski, Riitta; Dixon, Michael J.

    2014-01-01

    Appropriate development of stratified, squamous, keratinizing epithelia, such as the epidermis and oral epithelia, generates an outer protective permeability barrier that prevents water loss, entry of toxins, and microbial invasion. During embryogenesis, the immature ectoderm initially consists of a single layer of undifferentiated, cuboidal epithelial cells that stratifies to produce an outer layer of flattened periderm cells of unknown function. Here, we determined that periderm cells form in a distinct pattern early in embryogenesis, exhibit highly polarized expression of adhesion complexes, and are shed from the outer surface of the embryo late in development. Mice carrying loss-of-function mutations in the genes encoding IFN regulatory factor 6 (IRF6), IκB kinase-α (IKKα), and stratifin (SFN) exhibit abnormal epidermal development, and we determined that mutant animals exhibit dysfunctional periderm formation, resulting in abnormal intracellular adhesions. Furthermore, tissue from a fetus with cocoon syndrome, a lethal disorder that results from a nonsense mutation in IKKA, revealed an absence of periderm. Together, these data indicate that periderm plays a transient but fundamental role during embryogenesis by acting as a protective barrier that prevents pathological adhesion between immature, adhesion-competent epithelia. Furthermore, this study suggests that failure of periderm formation underlies a series of devastating birth defects, including popliteal pterygium syndrome, cocoon syndrome, and Bartsocas-Papas syndrome. PMID:25133425

  9. Natural Underwater Adhesives

    PubMed Central

    Stewart, Russell J.; Ransom, Todd C.; Hlady, Vladimir

    2011-01-01

    The general topic of this review is protein-based underwater adhesives produced by aquatic organisms. The focus is on mechanisms of interfacial adhesion to native surfaces and controlled underwater solidification of natural water-borne adhesives. Four genera that exemplify the broad range of function, general mechanistic features, and unique adaptations are discussed in detail: blue mussels, acorn barnacles, sandcastle worms, and freshwater caddisfly larva. Aquatic surfaces in nature are charged and in equilibrium with their environment, populated by an electrical double layer of ions as well as adsorbed natural polyelectrolytes and microbial biofilms. Surface adsorption of underwater bioadhesives likely occurs by exchange of surface bound ligands by amino acid sidechains, driven primarily by relative affinities and effective concentrations of polymeric functional groups. Most aquatic organisms exploit modified amino acid sidechains, in particular phosphorylated serines and hydroxylated tyrosines (dopa), with high-surface affinity that form coordinative surface complexes. After delivery to the surfaces as a fluid, permanent natural adhesives solidify to bear sustained loads. Mussel plaques are assembled in a manner superficially reminiscent of in vitro layer-by-layer strategies, with sequentially delivered layers associated through Fe(dopa)3 coordination bonds. The adhesives of sandcastle worms, caddisfly larva, and barnacles may be delivered in a form somewhat similar to in vitro complex coacervation. Marine adhesives are secreted, or excreted, into seawater that has a significantly higher pH and ionic strength than the internal environment. Empirical evidence suggests these environment triggers could provide minimalistic, fail-safe timing mechanisms to prevent premature solidification (insolubilization) of the glue within the secretory system, yet allow rapid solidification after secretion. Underwater bioadhesives are further strengthened by secondary covalent

  10. Abdominal wall reconstruction with implantable meshes.

    PubMed

    Masden, Derek; Felder, John M; Iorio, Matthew L; Bhanot, Parag; Attinger, Christopher E

    2011-01-01

    Abdominal wall defects present a difficult problem for the reconstructive surgeon. Over the years, numerous implantable materials have becomes available to aid the surgeon in recreating the abdominal wall. This spectrum of implants includes permanent synthetic meshes, absorbable meshes, composite meshes and biomaterials. This review includes the pros and cons for the commercially available abdominal wall implants as well as a review of the literature regarding outcomes for each material. This review will provide the surgeon with current evidence-based information on implantable abdominal materials to be able to make a more informed decision about which implant to use. PMID:21663579

  11. Elastomer toughened polyimide adhesives

    NASA Technical Reports Server (NTRS)

    St.clair, A. K.; St.clair, T. L. (Inventor)

    1983-01-01

    A rubber-toughened addition-type polyimide composition is disclosed which has excellent high temperature bonding characteristics in the fully cured state, and improved peel strength and adhesive fracture resistance physical property characteristics. The process for making the improved adhesive involves preparing the rubber containing amic acid prepolymer by chemically reacting an amine-terminated elastomer and an aromatic diamine with an aromatic dianhydride with which a reactive chain stopper anhydride was mixed, and utilizing solvent or mixture of solvents for the reaction.

  12. Metallic Adhesion and Bonding

    NASA Technical Reports Server (NTRS)

    Ferrante, J.; Smith, J. R.; Rose, J. H.

    1984-01-01

    Although metallic adhesion has played a central part in much tribological speculation, few quantitative theoretical calculations are available. This is in part because of the difficulties involved in such calculations and in part because the theoretical physics community is not particularly involved with tribology. The calculations currently involved in metallic adhesion are summarized and shown that these can be generalized into a scaled universal relationship. Relationships exist to other types of covalent bonding, such as cohesive, chemisorptive, and molecular bonding. A simple relationship between surface energy and cohesive energy is offered.

  13. Timer cover adhesive optimization

    SciTech Connect

    Carleton, J.J. II.

    1992-03-17

    The implementation of PROCODE as the data acquisition system for processing timers has required some modifications to the method of identifying timer assemblies. PROCODE requires machine-readable labelling of the assemblies. This report describes a series of experiments to find an adhesive that would keep labels attached to timers regardless of the condition of their surface when the label was applied and regardless of the heat, vibration, and shock they endured afterwards. The effect of the variation of these experimental factors on the performance of the adhesive was determined by using a Taguchi experimental design.

  14. Novel pathways in the pathobiology of human abdominal aortic aneurysms

    PubMed Central

    Hinterseher, Irene; Erdman, Robert; Elmore, James R; Stahl, Elizabeth; Pahl, Matthew C; Derr, Kimberly; Golden, Alicia; Lillvis, John H; Cindric, Matthew C; Jackson, Kathryn; Bowen, William D; Schworer, Charles M; Chernousov, Michael A; Franklin, David P; Gray, John L; Garvin, Robert P; Gatalica, Zoran; Carey, David J; Tromp, Gerard; Kuivaniemi, Helena

    2012-01-01

    Objectives Abdominal aortic aneurysm (AAA), a dilatation of the infrarenal aorta, typically affects males > 65 years. The pathobiological mechanisms of human AAA are poorly understood. The goal of this study was to identify novel pathways involved in the development of AAAs. Methods A custom-designed “AAA-chip” was used to assay 43 of the differentially expressed genes identified in a previously published microarray study between AAA (n = 15) and control (n = 15) infrarenal abdominal aorta. Protein analyses were performed on selected genes. Results Altogether 38 of the 43 genes on the “AAA-chip” showed significantly different expression. Novel validated genes in AAA pathobiology included ADCY7, ARL4C, BLNK, FOSB, GATM, LYZ, MFGE8, PRUNE2, PTPRC, SMTN, TMODI and TPM2. These genes represent a wide range of biological functions, such as calcium signaling, development and differentiation, as well as cell adhesion not previously implicated in AAA pathobiology. Protein analyses for GATM, CD4, CXCR4, BLNK, PLEK, LYZ, FOSB, DUSP6, ITGA5 and PTPRC confirmed the mRNA findings. Conclusion The results provide new directions for future research into AAA pathogenesis to study the role of novel genes confirmed here. New treatments and diagnostic tools for AAA could potentially be identified by studying these novel pathways. PMID:22797469

  15. Adhesions and Healing of Intestinal Anastomoses: The Effect of Anti-Adhesion Barriers.

    PubMed

    Ntourakis, Dimitrios; Katsimpoulas, Michail; Tanoglidi, Anna; Barbatis, Calypso; Karayannacos, Panayotis E; Sergentanis, Theodoros N; Kostomitsopoulos, Nikolaos; Machairas, Anastasios

    2016-06-01

    Background Postoperative adhesions are the result of aberrant peritoneal healing. As they are the leading cause of postoperative bowel obstruction, anti-adherence barriers are advocated for their prevention. This study looks into the effect of these biomaterials on the healing of intestinal anastomoses. Materials and Methods Thirty-three New Zealand White rabbits underwent laparotomy, transection of the terminal ileum, and creation of an end-to-end anastomosis. Animals were randomized into 3 groups: the Control group (n = 11); the Icodextrin group, receiving icodextrin 4% intraperitonealy (n = 11); and the HA/CMC group, having the anastomosis wrapped with a hyaluronic acid/carboxymethylcellulose film (n = 11). All animals were sacrificed on the seventh postoperative day. Macroscopic adhesions were graded and anastomotic strength was tested by the burst pressure. Histological healing was assessed in a semiquantitative way for the presence of ulceration, reepithelization, granulation tissue, inflammation, eosinophilic infiltration, serosal inflammation, and microscopic adhesions. Univariate and multivariate analysis was used. Results are given as medians with interquartile range. Results The median adhesion scores were the following: Control 1 (0-3), Icodextrin 0 (0-1), HA/CMC 0 (0-0), P = .017. The burst pressure did not differ between the groups; however, all except one bowel segments tested burst away from the anastomosis. The macroscopic and histological anastomotic healing was comparable in all 3 groups. A poor histological anastomotic healing score was associated with a higher adhesion grade (odds ratio = 1.92; 95% confidence interval = 1.06-3.47; P = .032). Conclusion Adhesion formation was inhibited by the materials tested without direct detrimental effects on anastomotic healing. Poor anastomotic healing provokes adhesions even in the presence of anti-adhesion barriers. PMID:26474604

  16. 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.

  17. A Continuum Approach to Modelling Cell-Cell Adhesion

    PubMed Central

    Armstrong, Nicola J.; Painter, Kevin J.; Sherratt, Jonathan A.

    2007-01-01

    Cells adhere to each other through the binding of cell adhesion molecules at the cell surface. This process, known as cell-cell adhesion, is fundamental in many areas of biology, including early embryo development, tissue homeostasis and tumour growth. In this paper we develop a new continuous mathematical model of this phenomenon by considering the movement of cells in response to the adhesive forces generated through binding. We demonstrate that our model predicts the aggregation behaviour of a disassociated adhesive cell population. Further, when the model is extended to represent the interactions between multiple populations, we demonstrate that it is capable of replicating the different types of cell sorting behaviour observed experimentally. The resulting pattern formation is a direct consequence of the relative strengths of self-population and cross-population adhesive bonds in the model. While cell sorting behaviour has been captured previously with discrete approaches, it has not, until now, been observed with a fully continuous model. PMID:16860344

  18. Cell Adhesion on Amyloid Fibrils Lacking Integrin Recognition Motif.

    PubMed

    Jacob, Reeba S; George, Edna; Singh, Pradeep K; Salot, Shimul; Anoop, Arunagiri; Jha, Narendra Nath; Sen, Shamik; Maji, Samir K

    2016-03-01

    Amyloids are highly ordered, cross-β-sheet-rich protein/peptide aggregates associated with both human diseases and native functions. Given the well established ability of amyloids in interacting with cell membranes, we hypothesize that amyloids can serve as universal cell-adhesive substrates. Here, we show that, similar to the extracellular matrix protein collagen, amyloids of various proteins/peptides support attachment and spreading of cells via robust stimulation of integrin expression and formation of integrin-based focal adhesions. Additionally, amyloid fibrils are also capable of immobilizing non-adherent red blood cells through charge-based interactions. Together, our results indicate that both active and passive mechanisms contribute to adhesion on amyloid fibrils. The present data may delineate the functional aspect of cell adhesion on amyloids by various organisms and its involvement in human diseases. Our results also raise the exciting possibility that cell adhesivity might be a generic property of amyloids. PMID:26742841

  19. Switchable Adhesion in Vacuum Using Bio-Inspired Dry Adhesives.

    PubMed

    Purtov, Julia; Frensemeier, Mareike; Kroner, Elmar

    2015-11-01

    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 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. PMID:26457864

  20. 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

  1. Wood Composite Adhesives

    NASA Astrophysics Data System (ADS)

    Gomez-Bueso, Jose; Haupt, Robert

    The global environment, in which phenolic resins are being used for wood composite manufacture, has changed significantly during the last decade. This chapter reviews trends that are driving the use and consumption of phenolic resins around the world. The review begins with recent data on volume usage and regional trends, followed by an analysis of factors affecting global markets. In a section on environmental factors, the impact of recent formaldehyde emission regulations is discussed. The section on economics introduces wood composite production as it relates to the available adhesive systems, with special emphasis on the technical requirement to improve phenolic reactivity. Advances in composite process technology are introduced, especially in regard to the increased demands the improvements place upon adhesive system performance. The specific requirements for the various wood composite families are considered in the context of adhesive performance needs. The results of research into current chemistries are discussed, with a review of recent findings regarding the mechanisms of phenolic condensation and acceleration. Also, the work regarding alternate natural materials, such as carbohydrates, lignins, tannins, and proteinaceous materials, is presented. Finally, new developments in alternative adhesive technologies are reported.

  2. Adept Adhesion Reduction Solution

    MedlinePlus

    ... icodextrin. The fluid is used during or after laparoscopic gynecological surgery to separate and protect tissues and decrease the number of new adhesions after surgery. Adept® is supplied sterile, in a single-use bag. How does it work? During surgery, ...

  3. Adhesion molecules and receptors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adhesion molecules are necessary for leukocyte trafficking and differentiation. They serve to initiate cell-cell interactions under conditions of shear, and they sustain the cell-cell and cell-matrix interactions needed for cellular locomotion. They also can serve directly as signaling molecules act...

  4. Rapid adhesive bonding concepts

    NASA Technical Reports Server (NTRS)

    Stein, B. A.; Tyeryar, J. R.; Hodges, W. T.

    1984-01-01

    Adhesive bonding in the aerospace industry typically utilizes autoclaves or presses which have considerable thermal mass. As a consequence, the rates of heatup and cooldown of the bonded parts are limited and the total time and cost of the bonding process is often relatively high. Many of the adhesives themselves do not inherently require long processing times. Bonding could be performed rapidly if the heat was concentrated in the bond lines or at least in the adherends. Rapid adhesive bonding concepts were developed to utilize induction heating techniques to provide heat directly to the bond line and/or adherends without heating the entire structure, supports, and fixtures of a bonding assembly. Bonding times for specimens are cut by a factor of 10 to 100 compared to standard press bonding. The development of rapid adhesive bonding for lap shear specimens (per ASTM D1003 and D3163), for aerospace panel bonding, and for field repair needs of metallic and advanced fiber reinforced polymeric matrix composite structures are reviewed.

  5. Resistance heating releases structural adhesive

    NASA Technical Reports Server (NTRS)

    Glemser, N. N.

    1967-01-01

    Composite adhesive package bonds components together for testing and enables separation when testing is completed. The composite of adhesives, insulation and a heating element separate easily when an electrical current is applied.

  6. Adhesion testing of aircraft tires

    NASA Technical Reports Server (NTRS)

    Bobo, S. N.

    1983-01-01

    Adhesion testing appeared to offer a less burdensome alternative to replace some of the dynamometer tests. Accordingly, test results and data were requested from retreaders who had used adhesion testing.

  7. 3-D foam adhesive deposition

    NASA Technical Reports Server (NTRS)

    Lemons, C. R.; Salmassy, O. K.

    1976-01-01

    Bonding method, which reduces amount and weight of adhesive, is applicable to foam-filled honeycomb constructions. Novel features of process include temperature-viscosity control and removal of excess adhesive by transfer to cellophane film.

  8. 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. PMID:7983255

  9. Pediatric Abdominal Pain: An Emergency Medicine Perspective.

    PubMed

    Smith, Jeremiah; Fox, Sean M

    2016-05-01

    Abdominal pain is a common complaint that leads to pediatric patients seeking emergency care. The emergency care provider has the arduous task of determining which child likely has a benign cause and not missing the devastating condition that needs emergent attention. This article reviews common benign causes of abdominal pain as well as some of the cannot-miss emergent causes. PMID:27133248

  10. Hypoxia inhibits abdominal expiratory nerve activity.

    PubMed

    Fregosi, R F; Knuth, S L; Ward, D K; Bartlett, D

    1987-07-01

    Our purpose was to examine the influence of steady-state changes in chemical stimuli, as well as discrete peripheral chemoreceptor stimulation, on abdominal expiratory motor activity. In decerebrate, paralyzed, vagotomized, and ventilated cats that had bilateral pneumothoraces, we recorded efferent activity from a phrenic nerve and from an abdominal nerve (cranial iliohypogastric nerve, L1). All cats showed phasic expiratory abdominal nerve discharge at normocapnia [end-tidal PCO2 38 +/- 2 Torr], but small doses (2-6 mg/kg) of pentobarbital sodium markedly depressed this activity. Hyperoxic hypercapnia consistently enhanced abdominal expiratory activity and shortened the burst duration. Isocapnic hypoxia caused inhibition of abdominal nerve discharge in 11 of 13 cats. Carotid sinus nerve denervation (3 cats) exacerbated the hypoxic depression of abdominal nerve activity and depressed phrenic motor output. Stimulation of peripheral chemoreceptors with NaCN increased abdominal nerve discharge in 7 of 10 cats, although 2 cats exhibited marked inhibition. Four cats with intact neuraxis, but anesthetized with ketamine, yielded qualitatively similar results. We conclude that when cats are subjected to steady-state chemical stimuli in isolation (no interference from proprioceptive inputs), hypercapnia potentiates, but hypoxia attenuates, abdominal expiratory nerve activity. Mechanisms to explain the selective inhibition of expiratory motor activity by hypoxia are proposed, and physiological implications are discussed. PMID:3624126

  11. The evolution of adhesiveness as a social adaptation

    PubMed Central

    Garcia, Thomas; Doulcier, Guilhem; De Monte, Silvia

    2015-01-01

    Cellular adhesion is a key ingredient to sustain collective functions of microbial aggregates. Here, we investigate the evolutionary origins of adhesion and the emergence of groups of genealogically unrelated cells with a game-theoretical model. The considered adhesiveness trait is costly, continuous and affects both group formation and group-derived benefits. The formalism of adaptive dynamics reveals two evolutionary stable strategies, at each extreme on the axis of adhesiveness. We show that cohesive groups can evolve by small mutational steps, provided the population is already endowed with a minimum adhesiveness level. Assortment between more adhesive types, and in particular differential propensities to leave a fraction of individuals ungrouped at the end of the aggregation process, can compensate for the cost of increased adhesiveness. We also discuss the change in the social nature of more adhesive mutations along evolutionary trajectories, and find that altruism arises before directly beneficial behavior, despite being the most challenging form of cooperation. DOI: http://dx.doi.org/10.7554/eLife.08595.001 PMID:26613415

  12. Robust and tailored wet adhesion in biopolymer thin films.

    PubMed

    Pettersson, Torbjörn; Pendergraph, Samuel A; Utsel, Simon; Marais, Andrew; Gustafsson, Emil; Wågberg, Lars

    2014-12-01

    Model layer-by-layer (LbL) assemblies of poly(allylamine hydrochloride) (PAH) and hyaluronic acid (HA) were fabricated in order to study their wet adhesive behavior. The film characteristics were investigated to understand the inherent structures during the assembly process. Subsequently, the adhesion of these systems was evaluated to understand the correlation between the structure of the film and the energy required to separate these LbL assemblies. We describe how the conditions of the LbL fabrication can be utilized to control the adhesion between films. The characteristics of the film formation are examined in the absence and presence of salt during the film formation. The dependence on contact time and LbL film thickness on the critical pull-off force and work of adhesion are discussed. Specifically, by introducing sodium chloride (NaCl) in the assembly process, the pull-off forces can be increased by a factor of 10 and the work of adhesion by 2 orders of magnitude. Adjusting both the contact time and the film thickness enables control of the adhesive properties within these limits. Based on these results, we discuss how the fabrication procedure can create tailored adhesive interfaces with properties surpassing analogous systems found in nature. PMID:25333327

  13. Autotransfusion utilization in abdominal trauma.

    PubMed

    Smith, L A; Barker, D E; Burns, R P

    1997-01-01

    The purpose of this review is to investigate the utility of autotransfusion in trauma patients in the past 3 years. A retrospective review was conducted of the charts for whom the Haemonetics Cell Saver autotransfusion device (Haemonetics Corp., Natick, MA) was utilized between January 1, 1993, and December 31, 1995. The estimated blood loss and quantity of blood transfused were noted for abdominal trauma patients. Costs of autotransfusion were then compared to estimated blood bank costs for this group. The Haemonetics Cell Saver autotransfusion device was requested for 592 cases from January 1, 1993, to December 31, 1995. Nonorthopedic trauma cases comprised 25 per cent of all autotransfusion cases. One hundred twenty-six patients had isolated abdominal trauma and had a mean estimated blood loss of 4864 +/- 6070 cc. The average volume of intraoperatively salvaged autologous blood transfused (autotransfusion) per patient was 1547 +/- 2359 cc, or a bank blood equivalent of 6.9 units of packed red blood cells. The total cost of autotransfusion in these patients was $63,252.00. Had bank blood been used instead of salvaged autologous blood, the cost would have been $114,523.00; thus, autotransfusion resulted in a savings of $51,271.00. The use of salvaged autologous blood comprised 45 per cent of total blood transfused. On a case-by-case basis, 75 per cent of cases were cost-effective compared to blood bank costs for an equivalent transfusion. Transfusion of intraoperatively salvaged autologous blood (autotransfusion) is a cost-effective, efficient way to provide blood products to operative trauma patients. PMID:8985070

  14. Low-temperature full wafer adhesive bonding

    NASA Astrophysics Data System (ADS)

    Niklaus, Frank; Enoksson, Peter; Kälvesten, Edvard; Stemme, Göran

    2001-03-01

    We have systematically investigated the influence of different bonding parameters on void formation in a low-temperature adhesive bonding process. As a result of these studies we present guidelines for void free adhesive bonding of 10 cm diameter wafers. We have focused on polymer coatings with layer thicknesses between 1 µm and 18 µm. The tested polymer materials were benzocyclobutene (BCB) from Dow Chemical, a negative photoresist (ULTRA-i 300) and a positive photoresist (S1818) from Shipley, a polyimide (HTR3) from Arch Chemical and two different polyimides (PI2555 and PI2610) from DuPont. The polymer material, the bonding pressure and the pre-curing time and temperature for the polymer significantly influence void formation at the bond interface. High bonding pressure and optimum pre-curing times/temperatures counteract void formation. We present the process parameters to achieve void-free bonding with the BCB coating and with the ULTRA-i 300 photoresist coating as adhesive materials. Excellent void-free and strong bonds have been achieved by using BCB as the bonding material which requires a minimum bonding temperature of 180 °C.

  15. Giant horseshoe intra-abdominal abscess.

    PubMed Central

    Altemeier, W A; Culbertson, W R; Fidler, J P

    1975-01-01

    A study of 12 patients with giant horseshoe abscess of the abdominal and pelvic cavities seen at the Surgical Services of the University of Cincinnati Medical Center has emphasized the complexity and bizarre nature of these lesions. These infections represented a huge abscess or series of communicating abscesses extending from one subphrenic space along the corresponding paracolic gutter into the pelvis, up and along the opposite paracolic space, and into the other subphrenic space. Since these lesions occurred infrequently, they were often not recognized until they had become far advanced and had produced profound effects on the patients. The diagnosis was difficult and obscured by various factors including the postoperative state after laparotomy for complex diseases or serious injuries of the biliary tract, the genitourinary tract, or the alimentary tract. An important etiologic component of the formation of these giant abscesses was the continuing escape and collection of large volumes of fluid resulting from lesions of the biliary tract, postoperative hemorrhage, or an unrecognized large perforated peptic ulcer. Nine patients were treated successfully and 3 died. The many diagnostic and therapeutic problems presented by the patients with this interesting and complex lesion have emphasized the importance of earlier and more accurate diagnosis, early and adequate surgical drainage, intelligently applied antibiotic therapy and appropriate supportive treatment. Failure to recognize and drain effectively each of the component sections of this lesion led to continuing sepsis with prolonged morbidity, progressive debility, and death. Images Fig. 1. Fig. 2. PMID:1079447

  16. Focal Adhesion Kinase-Dependent Regulation of Adhesive Force Involves Vinculin Recruitment to Focal Adhesions

    PubMed Central

    Hanks, Steven K.; García, Andrés J.

    2016-01-01

    Background information Focal adhesion kinase (FAK), an essential non-receptor tyrosine kinase, plays pivotal roles in migratory responses, adhesive signaling, and mechanotransduction. FAK-dependent regulation of cell migration involves focal adhesion turnover dynamics as well as actin cytoskeleton polymerization and lamellipodia protrusion. Whereas roles for FAK in migratory and mechanosensing responses have been established, the contributions of FAK to the generation of adhesive forces are not well understood. Results Using FAK-null cells expressing wild-type and mutant FAK under an inducible tetracycline promoter, we analyzed the role of FAK in the generation of steady-state adhesive forces using micropatterned substrates and a hydrodynamic adhesion assay. FAK expression reduced steady-state strength by 30% compared to FAK-null cells. FAK expression reduced vinculin localization to focal adhesions by 35% independently from changes in integrin binding and localization of talin and paxillin. RNAi knockdown of vinculin abrogated the FAK-dependent differences in adhesive force. FAK-dependent changes in vinculin localization and adhesive force were confirmed in human primary fibroblasts with FAK knocked down by RNAi. The autophosphorylation Y397 and kinase domain Y576/Y577 sites were differentially required for FAK-mediated adhesive responses. Conclusions We demonstrate that FAK reduces steady-state adhesion strength by modulating vinculin recruitment to focal adhesions. These findings provide insights into the role of FAK in mechanical interactions between a cell and the extracellular matrix. PMID:19883375

  17. Physics of cell elasticity, shape and adhesion

    NASA Astrophysics Data System (ADS)

    Safran, S. A.; Gov, N.; Nicolas, A.; Schwarz, U. S.; Tlusty, T.

    2005-07-01

    We review recent theoretical work that analyzes experimental measurements of the shape, fluctuations and adhesion properties of biological cells. Particular emphasis is placed on the role of the cytoskeleton and cell elasticity and we contrast the shape and adhesion of elastic cells with fluid-filled vesicles. In red blood cells (RBC), the cytoskeleton consists of a two-dimensional network of spectrin proteins. Our analysis of the wavevector and frequency dependence of the fluctuation spectrum of RBC indicates that the spectrin network acts as a confining potential that reduces the fluctuations of the lipid bilayer membrane. However, since the cytoskeleton is only sparsely connected to the bilayer, one cannot regard the composite cytoskeleton-membrane as a polymerized object with a shear modulus. The sensitivity of RBC fluctuations and shapes to ATP concentration may reflect topological defects induced in the cytoskeleton network by ATP. The shapes of cells that adhere to a substrate are strongly determined by the cytoskeletal elasticity that can be varied experimentally by drugs that depolymerize the cytoskeleton. This leads to a tension-driven retraction of the cell body and a pearling instability of the resulting ray-like protrusions. Recent experiments have shown that adhering cells exert polarized forces on substrates. The interactions of such “force dipoles” in either bulk gels or on surfaces can be used to predict the nature of self-assembly of cell aggregates and may be important in the formation of artificial tissues. Finally, we note that cell adhesion strongly depends on the forces exerted on the adhesion sites by the tension of the cytoskeleton. The size and shape of the adhesion regions are strongly modified as the tension is varied and we present an elastic model that relates this tension to deformations that induce the recruitment of new molecules to the adhesion region. In all these examples, cell shape and adhesion differ from vesicle shape and

  18. Adhesion of hydrogels under water by hydrogen bonding: from molecular interactions to macroscopic adhesion

    NASA Astrophysics Data System (ADS)

    Creton, Costantino

    2012-02-01

    Hydrogels are an essential part of living organisms and are widely used in biotechnologies, health care and food science. Although swelling properties, cell adhesion on gel surfaces and gel elasticity have attracted much interest, macroscopic adhesion of hydrogels on solid surfaces in aqueous environment is much less well understood. We studied systematically and in aqueous environment, the reversible adhesion by hydrogen bonding of macroscopic model hydrogels of polydimethylacrylamide (PDMA) or of polyacrylamide (PAAm) on solid surfaces functionalized with polyacrylic acid (PAA) polymer brushes. The hydrogels were synthesized by free radical polymerization and the brushes were prepared by grafting polytertbutyl acrylate chains and converting them by pyrolisis into polyacrylic acid. A new adhesion tester based on the flat punch geometry was designed and used to control the contact area, contact time, contact pressure and debonding velocity of the gels from the surface while the samples were fully immersed in water. The adhesion tests were performed at different pH and temperatures and the modulus of the gel and grafting density and molecular weight of the brushes was varied. Macroscopic adhesion results were compared with phase diagrams in dilute solution to detect molecular interactions. While the PDMA/PAA pair behaved very similarly in solution and in macroscopic adhesion tests, the PAAm/PAA pair showed an unexpectedly high adhesion level relatively to its complexation ability in dilute solution. Surprisingly, time dependent experiments showed that the kinetics of H-bond formation and breakup at interfaces was very slow resulting in adhesion energies which were very dependent on contact time up to one hour of contact. At the molecular level, neutron reflectivity showed that the equilibrium brush conformation when in contact with the gels was more extended at pH2 (H-bonds activated) than at pH9 (H-bonds deactivated) and that a certain applied pressure was

  19. Adhesive transfer of thin viscoelastic films.

    PubMed

    Shull, Kenneth R; Martin, Elizabeth F; Drzal, Peter L; Hersam, Mark C; Markowitz, Alison R; McSwain, Rachel L

    2005-01-01

    Micellar suspensions of acrylic diblock copolymers are excellent model materials for studying the adhesive transfer of viscoelastic solids. The micellar structure is maintained in films with a variety of thicknesses, giving films with a well-defined structure and viscoelastic character. Thin films were cast onto elastomeric silicone substrates from micellar suspensions in butanol, and the adhesive interactions between these coated elastomeric substrates and a rigid indenter were quantified. By controlling the adhesive properties of the film/indenter and film/substrate interfaces we were able to obtain very clean transfer of the film from the substrate to the portion of the glass indenter with which the film was in contact. Adhesive failure at the film/substrate interface occurs when the film/indenter interface is able to support an applied energy release rate that is sufficient to result in cavity nucleation at the film/substrate interface. Cavity formation is rapidly followed by delamination of the entire region under the indenter. The final stage in the transfer process involves the failure of the film that bridges the indenter and the elastomeric substrate. This film is remarkably robust and is extended to three times its original width prior to failure. Failure of this film occurs at the periphery of the indenter, giving a transferred film that conforms to the original contact area between the indenter and the coated substrate. PMID:15620300

  20. Adhesion behaviors on superhydrophobic surfaces.

    PubMed

    Zhu, Huan; Guo, Zhiguang; Liu, Weimin

    2014-04-18

    The adhesion behaviors of superhydrophobic surfaces have become an emerging topic to researchers in various fields as a vital step in the interactions between materials and organisms/materials. Controlling the chemical compositions and topological structures via various methods or technologies is essential to fabricate and modulate different adhesion properties, such as low-adhesion, high-adhesion and anisotropic adhesion on superhydrophobic surfaces. We summarize the recent developments in both natural superhydrophobic surfaces and artificial superhydrophobic surfaces with various adhesions and also pay attention to superhydrophobic surfaces switching between low- and high-adhesion. The methods to regulate or translate the adhesion of superhydrophobic surfaces can be considered from two perspectives. One is to control the chemical composition and change the surface geometric structure on the surfaces, respectively or simultaneously. The other is to provide external stimulations to induce transitions, which is the most common method for obtaining switchable adhesions. Additionally, adhesion behaviors on solid-solid interfaces, such as the behaviors of cells, bacteria, biomolecules and icing on superhydrophobic surfaces are also noticeable and controversial. This review is aimed at giving a brief and crucial overview of adhesion behaviors on superhydrophobic surfaces. PMID:24575424

  1. Clinical Recommendation: Labial Adhesions.

    PubMed

    Bacon, Janice L; Romano, Mary E; Quint, Elisabeth H

    2015-10-01

    Labial adhesions, also known as labial agglutination, are a common finding in prepubertal adolescents. They are defined as fusion of the labia minora in the midline or are termed vulvar adhesions when they occur below the labia minora (inner labia). Patients are often asymptomatic but might present with genitourinary complaints. The decision for treatment is based on symptoms. The mainstay of treatment in asymptomatic patients is conservative, with careful attention to vulvar hygiene and reassurance to parents. In symptomatic patients, topical treatment with estrogen and/or steroid cream is often curative. Less often, corrective surgery is necessary. Recurrence is common until a patient goes through puberty. These recommendations are intended for pediatric and gynecologic health care providers who care for pediatric and adolescent girls to facilitate diagnosis and treatment. PMID:26162697

  2. Environmentally compliant adhesive joining technology

    SciTech Connect

    Tira, J.S.

    1996-08-01

    Adhesive joining offers one method of assembling products. Advantages of adhesive joining/assembly include distribution of applied forces, lighter weight, appealing appearance, etc. Selecting environmentally safe adhesive materials and accompanying processes is paramount in today`s business climate if a company wants to be environmentally conscious and stay in business. Four areas of adhesive joining (adhesive formulation and selection, surface preparation, adhesive bonding process, waste and pollution generation/cleanup/management) all need to be carefully evaluated before adhesive joining is selected for commercial as well as military products. Designing for six sigma quality must also be addressed in today`s global economy. This requires material suppliers and product manufacturers to work even closer together.

  3. Ceramic microstructure and adhesion

    NASA Technical Reports Server (NTRS)

    Buckley, D. H.

    1984-01-01

    When a ceramic is brought into contact with a ceramic, a polymer, or a metal, strong bond forces can develop between the materials. The bonding forces will depend upon the state of the surfaces, cleanliness and the fundamental properties of the two solids, both surface and bulk. Adhesion between a ceramic and another solid are discussed from a theoretical consideration of the nature of the surfaces and experimentally by relating bond forces to interface resulting from solid state contact. Surface properties of ceramics correlated with adhesion include, orientation, reconstruction and diffusion as well as the chemistry of the surface specie. Where a ceramic is in contact with a metal their interactive chemistry and bond strength is considered. Bulk properties examined include elastic and plastic behavior in the surficial regions, cohesive binding energies, crystal structures and crystallographic orientation. Materials examined with respect to interfacial adhesive interactions include silicon carbide, nickel zinc ferrite, manganese zinc ferrite, and aluminum oxide. The surfaces of the contacting solids are studied both in the atomic or molecularly clean state and in the presence of selected surface contaminants.

  4. 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. PMID:20952618

  5. 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

  6. [The patient with intra-abdominal hypertension].

    PubMed

    Sakka, Samir G

    2016-01-01

    An intra-abdominal hypertension (IAH) defined as a pathological increase in intra-abdominal pressure (IAP) is commonly found on ICU admission or during the ICU stay. Several studies confirmed that an IAH is an independent predictor for mortality of critically ill patients. The abdominal compartment syndrome (ACS) which is defined as a sustained IAP>20 mmHg (with or without an abdominal perfusion pressure [APP]<60mmHg) that is associated with new organ dysfunction or failure has a mortality of up to 60%. In general, an IAH may be induced by several intra-abdominal as well as extra-abdominal conditions. Reduced abdominal wall compliance, intra-abdominal pathologies (either of the peritoneal space or parenchymateous organs) may lead to an IAH. Most commonly, intra-abdominal infections and/or sepsis and severe trauma or burns are predisposing for an IAH. An early sign may be a decrease in urinary output. The effects of an increased IAP on cardiovascular function are well recognized and include negative effects on preload, afterload and contractility. However, all other compartments of the body may be affected by an IAH. Thus, by an increase of the respective compartment pressure, e.g. intracranial pressure, a poly-compartment syndrome may result. Adequate prevention, a forward-looking strategy, and objective techniques for measurement of IAP are required to avoid or early detect an IAH or ACS. Finally, an immediate and consequent interdisciplinary management using conservative, interventional and operative options are necessary to solve an IAH or ACS. PMID:26863642

  7. Low Ice Adhesion on Nano-Textured Superhydrophobic Surfaces under Supersaturated Conditions.

    PubMed

    Bengaluru Subramanyam, Srinivas; Kondrashov, Vitaliy; Rühe, Jürgen; Varanasi, Kripa K

    2016-05-25

    Ice adhesion on superhydrophobic surfaces can significantly increase in humid environments because of frost nucleation within the textures. Here, we studied frost formation and ice adhesion on superhydrophobic surfaces with various surface morphologies using direct microscale imaging combined with macroscale adhesion tests. Whereas ice adhesion increases on microtextured surfaces, a 15-fold decrease is observed on nanotextured surfaces. This reduction is because of the inhibition of frost formation within the nanofeatures and the stabilization of vapor pockets. Such "Cassie ice"-promoting textures can be used in the design of anti-icing surfaces. PMID:27150450

  8. Abdominal Pain in the Geriatric Patient.

    PubMed

    Leuthauser, Amy; McVane, Benjamin

    2016-05-01

    Abdominal pain in the elderly can be a challenging and difficult condition to diagnose and treat. The geriatric population has significant comorbidities and often takes polypharmacy that can mask symptoms. The presentation of common conditions can be different than that in the younger population, often lacking the traditional indicators of disease, making it of pivotal importance for the clinician to consider a wide differential during their workup. It is also important to consider extra-abdominal abnormality that may manifest as abdominal pain. PMID:27133249

  9. Chylous Ascites after Abdominal Aortic Aneurysm Repair

    PubMed Central

    Ohki, Shinichi; Kurumisawa, Soki

    2015-01-01

    A 73-year-old man was transferred for treatment of abdominal aortic aneurysm. He had no history of abdominal surgeries. Grafting between the infra-renal abdominal aorta and the bilateral common iliac arteries was performed. Proximal and distal cross clamps were applied for grafting. He developed chylous ascites on the 5th post-operative day, 2 days after initiation of oral intake. Fortunately, he responded to treatment with total parenteral hyper-alimentation for 10 days, followed by a low-fat diet. There was no recurrence of ascites. PMID:27087873

  10. Chylous Ascites after Abdominal Aortic Aneurysm Repair.

    PubMed

    Ohki, Shinichi; Kurumisawa, Soki; Misawa, Yoshio

    2016-01-01

    A 73-year-old man was transferred for treatment of abdominal aortic aneurysm. He had no history of abdominal surgeries. Grafting between the infra-renal abdominal aorta and the bilateral common iliac arteries was performed. Proximal and distal cross clamps were applied for grafting. He developed chylous ascites on the 5th post-operative day, 2 days after initiation of oral intake. Fortunately, he responded to treatment with total parenteral hyper-alimentation for 10 days, followed by a low-fat diet. There was no recurrence of ascites. PMID:27087873

  11. [Diagnostic laparocentesis in closed abdominal injury].

    PubMed

    Berkutov, A N; Deriabin, I I; Zakurdaev, V E

    1976-09-01

    To improve the diagnosis of closed abdominal trauma since 1966 the authors have been widely employing laparocentesis. The results of using abdominal punctures an 260 patients are reported. The method proved to be reliable in 97.7%. The use of laparocentesis enabled the authors to reduce the number of errors by 7.3 times, to shorten the terms of establishing the diagnosis by 4 times as compared with the control group of patients (190 subjects in whom the recognition of abdominal injuries is based on common clinical symptoms). PMID:136785

  12. Combined subcutaneous, intrathoracic and abdominal splenosis.

    PubMed

    Javadrashid, Reza; Paak, Neda; Salehi, Ahad

    2010-09-01

    We report a case of combined subcutaneous, intrathoracic, and abdominal splenosis who presented with attacks of flushing, tachycardia and vague abdominal pain. The patient's past medical history included a splenectomy due to abdominal trauma and years later, a lung lobectomy due to recurrent pneumonia. An enhancing solid mass adjacent to the upper pole of the left kidney and nodular pleural based lesions in the left hemi-thorax along with nodular lesions in subcutaneous tissue of the left chest wall suggested possible adrenal malignancy with multiple metastases. Histopathologic examination demonstrated benign lesions of ectopic splenic tissue. PMID:20804314

  13. USE OF ALLOPLASTIC MESHES IN ABDOMINAL WOUNDS OF RATS WITH INDUCED PERITONITIS

    PubMed Central

    BARBUTO, Rafael Calvão; DUVAL-ARAUJO, Ivana; BARRAL, Sumara Marques; ROCHA, Raphael Grossi; BECHARA, Cristiane de Souza; BARBOSA, Alfredo José Afonso

    2014-01-01

    Background The use of alloplastic meshes has been historically contra-indicated in patients with infection. Aim To evaluate the use of polypropylene meshes in the treatment of abdominal wall defects in rats with peritonitis. Methods Twenty Wistar female rats were divided into two groups: induction of peritonitis (test group) and without peritonitis (control group). An abdominal wall defect was created in all animals, and polypropylene mesh was applied. The evaluation of the tensile strength of the mesh was carried out using tensiometer and microscopic analysis of the healing area was done. Results More adhesion of the mesh to the rat abdominal wall was observed in test group. The histopathological analyses showed prevalence of moderate to accentuated granulation tissue in both groups, without significant differences. Conclusion The use of the mesh coverage on abdominal wall defects of rats with induced peritonitis did not show worse results than its use in healthy animals, nor was its integration to the resident tissue any worse. PMID:24676294

  14. Imaging of abdominal aortic aneurysms.

    PubMed

    Sparks, Amy R; Johnson, Philip L; Meyer, Mark C

    2002-04-15

    Given the high rate of morbidity and mortality associated with abdominal aortic aneurysms (AAAs), accurate diagnosis and preoperative evaluation are essential for improved patient outcomes. Ultrasonography is the standard method of screening and monitoring AAAs that have not ruptured. In the past, aortography was commonly used for preoperative planning in the repair of AAAs. More recently, computed tomography (CT) has largely replaced older, more invasive methods. Recent advances in CT imaging technology, such as helical CT and CT angiography, offer significant advantages over traditional CT. These methods allow for more rapid scans and can produce three-dimensional images of the AAA and important adjacent vascular structures. Use of endovascular stent grafts has increased recently and is less invasive for the repair of AAAs in selected cases. Aortography and CT angiography can precisely determine the size and surrounding anatomy of the AAA to identify appropriate candidates for the use of endovascular stent grafts. Helical CT and CT angiography represent an exciting future in the preoperative evaluation of AAAs. However, this technology is not the standard of care because of the lack of widespread availability, the cost associated with obtaining new equipment, and the lack of universal protocols necessary for acquisition and reconstruction of these images. PMID:11989632

  15. Oxidative stress and abdominal aortic aneurysm: potential treatment targets.

    PubMed

    Emeto, Theophilus I; Moxon, Joseph V; Au, Minnie; Golledge, Jonathan

    2016-03-01

    Abdominal aortic aneurysm (AAA) is a significant cause of mortality in older adults. A key mechanism implicated in AAA pathogenesis is inflammation and the associated production of reactive oxygen species (ROS) and oxidative stress. These have been suggested to promote degradation of the extracellular matrix (ECM) and vascular smooth muscle apoptosis. Experimental and human association studies suggest that ROS can be favourably modified to limit AAA formation and progression. In the present review, we discuss mechanisms potentially linking ROS to AAA pathogenesis and highlight potential treatment strategies targeting ROS. Currently, none of these strategies has been shown to be effective in clinical practice. PMID:26814202

  16. 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

  17. 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

  18. 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.

  19. Genetics Home Reference: abdominal wall defect

    MedlinePlus

    ... size and can usually be diagnosed early in fetal development, typically between the tenth and fourteenth weeks of ... organs at the abdominal wall opening late in fetal development may also contribute to organ injury. Intestinal damage ...

  20. Abdominal pain - children under age 12

    MedlinePlus

    Stomach pain in children; Pain - abdomen - children; Abdominal cramps in children; Belly ache in children ... this kind of pain when they have a stomach virus, indigestion, gas, or when they become constipated. ...

  1. Familial abdominal chemodectomas with associated cutaneous angiolipomas.

    PubMed

    Lee, S P; Nicholson, G I; Hitchcock, G

    1977-04-01

    The occurrence of cutaneous angiolipomas and intra-abdominal retroperitoneal chemodectomas in two brothers is described. Both died from malignant dissemination of the chemodectomas. It is possible but speculative that two other brothers suffered from the same syndrome. PMID:195258

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

    PubMed Central

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

    2014-01-01

    OBJECTIVE: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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. PMID:25029580

  3. 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

  4. Sticky Matrix: Adhesion Mechanism of the Staphylococcal Polysaccharide Intercellular Adhesin.

    PubMed

    Formosa-Dague, Cécile; Feuillie, Cécile; Beaussart, Audrey; Derclaye, Sylvie; Kucharíková, Soňa; Lasa, Iñigo; Van Dijck, Patrick; Dufrêne, Yves F

    2016-03-22

    The development of bacterial biofilms on surfaces leads to hospital-acquired infections that are difficult to fight. In Staphylococci, the cationic polysaccharide intercellular adhesin (PIA) forms an extracellular matrix that connects the cells together during biofilm formation, but the molecular forces involved are unknown. Here, we use advanced force nanoscopy techniques to unravel the mechanism of PIA-mediated adhesion in a clinically relevant methicillin-resistant Staphylococcus aureus (MRSA) strain. Nanoscale multiparametric imaging of the structure, adhesion, and elasticity of bacteria expressing PIA shows that the cells are surrounded by a soft and adhesive matrix of extracellular polymers. Cell surface softness and adhesion are dramatically reduced in mutant cells deficient for the synthesis of PIA or under unfavorable growth conditions. Single-cell force spectroscopy demonstrates that PIA promotes cell-cell adhesion via the multivalent electrostatic interaction with polyanionic teichoic acids on the S. aureus cell surface. This binding mechanism rationalizes, at the nanoscale, the well-known ability of PIA to strengthen intercellular adhesion in staphylococcal biofilms. Force nanoscopy offers promising prospects for understanding the fundamental forces in antibiotic-resistant biofilms and for designing anti-adhesion compounds targeting matrix polymers. PMID:26908275

  5. Stimuli-Responsive Reversible Two-Level Adhesion from a Structurally Dynamic Shape-Memory Polymer.

    PubMed

    Michal, Brian T; Spencer, Emily J; Rowan, Stuart J

    2016-05-01

    A shape-memory adhesive has been prepared that exhibits two levels of reversible adhesion. The adhesive is a semicrystalline cross-linked polymer that contains dynamic disulfide bonds. Melting of the crystalline regions via heat causes a drop in the modulus of the material facilitating wetting of the substrate as well as enhancing the surface contact area with the substrate, which result in the formation of an adhesive bond. Exposure to higher heat or UV light results in dynamic exchange of the disulfide bonds, which yields a further drop in the modulus/viscosity that improves surface wetting/contact and strengthens the adhesive bond. This improvement in adhesion is shown to apply over different substrates, contact forces, and deformation modes. Furthermore, the adhesive acts as a thermal shape-memory material and can be used to create joints that can reposition themselves upon application of heat. PMID:27096252

  6. The value of laparoscopy in the diagnosis and therapy of violin-string like perihepatic nonpostoperative adhesions.

    PubMed

    Sarli, L; Villa, F; Iusco, D R

    2001-03-01

    We report three cases of Fitrz-Hugh Curtis syndrome (FHCs) that were diagnosed laparoscopically and showed microbiological or serological evidence of chlamydial infection. The case histories underscore the part played by abdominal right quadrant symptoms. In all three cases, right quadrant pain and tenderness constituted the presenting features. The patients were thought to have acute cholecystitis or acute appendicitis, but investigations proved negative. Laparoscopy was the key to the diagnosis, revealing the violin-string-like perihepatic adhesions typical of this syndrome. Lysis of the adhesions resolved the patients' symptoms of persistent severe abdominal pain. In the first case, the pain lessened dramatically only after the third operation, when the perihepatic adhesions were lysed. In the two other cases, the lysis was performed laparoscopically by fulguration and cutting. We consider this procedure to be an excellent therapeutic modality for the pain associated with FHCs. PMID:11344440

  7. Progress in Fully Automated Abdominal CT Interpretation

    PubMed Central

    Summers, Ronald M.

    2016-01-01

    OBJECTIVE Automated analysis of abdominal CT has advanced markedly over just the last few years. Fully automated assessment of organs, lymph nodes, adipose tissue, muscle, bowel, spine, and tumors are some examples where tremendous progress has been made. Computer-aided detection of lesions has also improved dramatically. CONCLUSION This article reviews the progress and provides insights into what is in store in the near future for automated analysis for abdominal CT, ultimately leading to fully automated interpretation. PMID:27101207

  8. Using abdominal massage in bowel management.

    PubMed

    Connor, Michelle; Hunt, Catherine; Lindley, Alison; Adams, John

    2014-07-15

    This article describes the introduction of abdominal massage techniques by a community team as part of a total bowel management programme for people with learning disabilities. A trust-wide audit of prescribed laxative use by this client group raised concerns, and led to a more systematic approach to managing constipation in people with learning disabilities. An education programme for carers proved to be successful. Some reported that adopting abdominal massage provided further opportunity to develop the therapeutic relationship. PMID:25005415

  9. A focus on intra-abdominal infections

    PubMed Central

    2010-01-01

    Complicated intra-abdominal infections are an important cause of morbidity and are frequently associated with poor prognosis, particularly in higher risk patients. Well defined evidence-based recommendations for intra-abdominal infections treatment are partially lacking because of the limited number of randomized-controlled trials. Factors consistently associated with poor outcomes in patients with intra-abdominal infections include increased illness severity, failed source control, inadequate empiric antimicrobial therapy and healthcare-acquired infection. Early prognostic evaluation of complicated intra-abdominal infections is important to select high-risk patients for more aggressive therapeutic procedures. The cornerstones in the management of complicated intra-abdominal infections are both source control and antibiotic therapy. The timing and the adequacy of source control are the most important issues in the management of intra-abdominal infections, because inadequate and late control of septic source may have a negative effect on the outcomes. Recent advances in interventional and more aggressive techniques could significantly decrease the morbidity and mortality of physiologically severe complicated intra-abdominal infections, even if these are still being debated and are yet not validated by limited prospective trials. Empiric antimicrobial therapy is nevertheless important in the overall management of intra-abdominal infections. Inappropriate antibiotic therapy may result in poor patient outcomes and in the appearance of bacterial resistance. Antimicrobial management is generally standardised and many regimens, either with monotherapy or combination therapy, have proven their efficacy. Routine coverage especially against Enterococci and candida spp is not always recommended, but can be useful in particular clinical conditions. A de escalation approach may be recommended in patients with specific risk factors for multidrug resistant infections such as

  10. Adhesion between silica surfaces due to hydrogen bonding

    NASA Astrophysics Data System (ADS)

    Bowen, James; Rossetto, Hebert L.; Kendall, Kevin

    2016-09-01

    The adhesion between surfaces can be enhanced significantly by the presence of hydrogen bonding. Confined water at the nanoscale can display behaviour remarkably different to bulk water due to the formation of hydrogen bonds between two surfaces. In this work we investigate the role of confined water on the interaction between hydrophilic surfaces, specifically the effect of organic contaminants in the aqueous phase, by measuring the peak adhesive force and the work of adhesion. Atomic force microscope cantilevers presenting hemispherical silica tips were interacted with planar single crystals of silica in the presence of dimethylformamide, ethanol, and formamide; solution compositions in the range 0–100 mol% water were investigated for each molecule. Each molecule was chosen for its ability to hydrogen bond with water molecules, with increasing concentrations likely to disrupt the structure of surface-bound water layers. With the exception of aqueous solutions containing low concentrations of ethanol, all molecules decreased the ability of confined water to enhance the adhesion between the silica surfaces in excess of the predicted theoretical adhesion due to van der Waals forces. The conclusion was that adhesion depends strongly on the formation of a hydrogen-bonding network within the water layers confined between the silica surfaces.

  11. 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

  12. Factors associated with abdominal obesity in children

    PubMed Central

    Melzer, Matheus Ribeiro Theodósio Fernandes; Magrini, Isabella Mastrangi; Domene, Semíramis Martins Álvares; Martins, Paula Andrea

    2015-01-01

    Objective: To identify the association of dietary, socioeconomic factors, sedentary behaviors and maternal nutritional status with abdominal obesity in children. Methods: A cross-sectional study with household-based survey, in 36 randomly selected census tracts in the city of Santos, SP. 357 families were interviewed and questionnaires and anthropometric measurements were applied in mothers and their 3-10 years-old children. Assessment of abdominal obesity was made by maternal and child's waist circumference measurement; for classification used cut-off points proposed by World Health Organization (1998) and Taylor et al. (2000) were applied. The association between variables was performed by multiple logistic regression analysis. Results: 30.5% of children had abdominal obesity. Associations with children's and maternal nutritional status and high socioeconomic status were shown in the univariate analysis. In the regression model, children's body mass index for age (OR=93.7; 95%CI 39.3-223.3), female gender (OR=4.1; 95%CI 1.8-9.3) and maternal abdominal obesity (OR=2.7; 95%CI 1.2-6.0) were significantly associated with children's abdominal obesity, regardless of the socioeconomic status. Conclusions: Abdominal obesity in children seems to be associated with maternal nutritional status, other indicators of their own nutritional status and female gender. Intervention programs for control of childhood obesity and prevention of metabolic syndrome should consider the interaction of the nutritional status of mothers and their children. PMID:26298655

  13. Genes and Abdominal Aortic Aneurysm

    PubMed Central

    Hinterseher, Irene; Tromp, Gerard; Kuivaniemi, Helena

    2010-01-01

    Abdominal aortic aneurysm (AAA) is a multifactorial disease with a strong genetic component. Since first candidate gene studies were published 20 years ago, nearly 100 genetic association studies using single nucleotide polymorphisms (SNPs) in biologically relevant genes have been reported on AAA. The studies investigated SNPs in genes of the extracellular matrix, the cardiovascular system, the immune system, and signaling pathways. Very few studies were large enough to draw firm conclusions and very few results could be replicated in another sample set. The more recent unbiased approaches are family-based DNA linkage studies and genome-wide genetic association studies, which have the potential of identifying the genetic basis for AAA, if appropriately powered and well-characterized large AAA cohorts are used. SNPs associated with AAA have already been identified in these large multicenter studies. One significant association was of a variant in a gene called CNTN3 which is located on chromosome 3p12.3. Two follow-up studies, however, could not replicate the association. Two other SNPs, which are located on chromosome 9p21 and 9q33 were replicated in other samples. The two genes with the strongest supporting evidence of contribution to the genetic risk for AAA are the CDKN2BAS gene, also known as ANRIL, which encodes an antisense RNA that regulates expression of the cyclin-dependent kinase inhibitors CDKN2A and CDKN2B, and DAB2IP, which encodes an inhibitor of cell growth and survival. Functional studies are now needed to establish the mechanisms by which these genes contribute to AAA pathogenesis. PMID:21146954

  14. Effect of osteopontin on the initial adhesion of dental bacteria.

    PubMed

    Schlafer, Sebastian; Meyer, Rikke L; Sutherland, Duncan S; Städler, Brigitte

    2012-12-28

    Bacterial biofilms are involved in numerous infections of the human body, including dental caries. While conventional therapy of biofilm diseases aims at eradication and mechanical removal of the biofilms, recent therapeutic approaches target the mechanisms of biofilm formation and bacterial adhesion in particular. The effect of bovine milk osteopontin, a highly phosphorylated whey protein, on adhesion of Streptococcus mitis, Streptococcus sanguinis, and Actinomyces naeslundii, three prominent colonizers in dental biofilms, to saliva-coated surfaces was investigated. While adhesion of A. naeslundii was not affected by osteopontin, a strong, dose-dependent reduction in the number of adhering S. mitis was shown. No difference in bacterial adhesion was observed for caseinoglycomacropeptide, another phosphorylated milk protein. Osteopontin did not affect bacterial viability, but changed bacterial surface hydrophobicity, and may be suggested to prevent the adhesins of S. mitis from interacting with their salivary receptors. The antiadhesive effect of osteopontin may be useful for caries prevention. PMID:23167781

  15. Simulation of Cell Adhesion using a Particle Transport Model

    NASA Astrophysics Data System (ADS)

    Chesnutt, Jennifer

    2005-11-01

    An efficient computational method for simulation of cell adhesion through protein binding forces is discussed. In this method, the cells are represented by deformable elastic particles, and the protein binding is represented by a rate equation. The method is first developed for collision and adhesion of two similar cells impacting on each other from opposite directions. The computational method is then applied in a particle-transport model for a cloud of interacting and colliding cells, each of which are represented by particles of finite size. One application might include red blood cells adhering together to form rouleaux, which are chains of red blood cells that are found in different parts of the circulatory system. Other potential applications include adhesion of platelets to a blood vessel wall or mechanical heart valve, which is a precursor of thrombosis formation, or adhesion of cancer cells to organ walls in the lymphatic, circulatory, digestive or pulmonary systems.

  16. Reusable antifouling viscoelastic adhesive with an elastic skin.

    PubMed

    Patil, Sandip; Malasi, Abhinav; Majumder, Abhijit; Ghatak, Animangsu; Sharma, Ashutosh

    2012-01-10

    Although the viscoelasticity or tackiness of a pressure-sensitive adhesive gives it strength owing to energy dissipation during peeling, it also renders it nonreusable because of structural changes such as the formation of fibrils, cohesive failure, and fouling. However, an elastic layer has good structural integrity and cohesive strength but low adhesive energy. We demonstrate an effective composite adhesive in which a soft viscoelastic bulk layer is imbedded in a largely elastic thin skin layer. The composite layer is able to meet the conflicting demands of the high peel strength comparable to the viscoelastic core and the structural integrity, reusability, and antifouling properties of the elastic skin. Our model adhesive is made of poly(dimethylsiloxane), where its core and skin are created by varying the cross-linking percentage from 2 to 10%. PMID:22201420

  17. JKR adhesion in cylindrical contacts

    NASA Astrophysics Data System (ADS)

    Sundaram, Narayan; Farris, T. N.; Chandrasekar, S.

    2012-01-01

    Planar JKR adhesive solutions use the half-plane assumption and do not permit calculation of indenter approach or visualization of adhesive force-displacement curves unless the contact is periodic. By considering a conforming cylindrical contact and using an arc crack analogy, we obtain closed-form indenter approach and load-contact size relations for a planar adhesive problem. The contact pressure distribution is also obtained in closed-form. The solutions reduce to known cases in both the adhesion-free and small-contact solution ( Barquins, 1988) limits. The cylindrical system shows two distinct regimes of adhesive behavior; in particular, contact sizes exceeding the critical (maximum) size seen in adhesionless contacts are possible. The effects of contact confinement on adhesive behavior are investigated. Some special cases are considered, including contact with an initial neat-fit and the detachment of a rubbery cylinder from a rigid cradle. A comparison of the cylindrical solution with the half-plane adhesive solution is carried out, and it indicates that the latter typically underestimates the adherence force. The cylindrical adhesive system is novel in that it possesses stable contact states that may not be attained even on applying an infinite load in the absence of adhesion.

  18. Dynamic Regulation of Activated Leukocyte Cell Adhesion Molecule–mediated Homotypic Cell Adhesion through the Actin CytoskeletonV⃞

    PubMed Central

    Nelissen, Judith M. D. T.; Peters, Inge M.; de Grooth, Bart G.; van Kooyk, Yvette; Figdor, Carl G.

    2000-01-01

    Restricted expression of activated leukocyte cell adhesion molecule (ALCAM) by hematopoietic cells suggests an important role in the immune system and hematopoiesis. To get insight into the mechanisms that control ALCAM-mediated adhesion we have investigated homotypic ALCAM–ALCAM interactions. Here, we demonstrate that the cytoskeleton regulates ALCAM-mediated cell adhesion because inhibition of actin polymerization by cytochalasin D (CytD) strongly induces homotypic ALCAM–ALCAM interactions. This induction of cell adhesion is likely due to clustering of ALCAM at the cell surface, which is observed after CytD treatment. Single-particle tracking demonstrated that the lateral mobility of ALCAM in the cell membrane is increased 30-fold after CytD treatment. In contrast, both surface distribution and adhesion of a glycosylphosphatidylinositol (GPI)-anchored ALCAM mutant are insensitive to CytD, despite the increase in lateral mobility of GPI-ALCAM upon CytD treatment. This demonstrates that clustering of ALCAM is essential for cell adhesion, whereas enhanced diffusion of ALCAM alone is not sufficient for cluster formation. In addition, upon ligand binding, both free diffusion and the freely dragged distance of wild-type ALCAM, but not of GPI-ALCAM, are reduced over time, suggesting strengthening of the cytoskeleton linkage. From these findings we conclude that activation of ALCAM-mediated adhesion is dynamically regulated through actin cytoskeleton-dependent clustering. PMID:10848629

  19. Stickiness--some fundamentals of adhesion.

    PubMed

    Gay, Cyprien

    2002-12-01

    We review some adhesion mechanisms that have been understood in the field of synthetic adhesives, and more precisely for adhesives that adhere instantaneously (a property named tackiness) and whose adhesive strength usually depends on the applied pressure (pressure-sensitive adhesives). The discussion includes effects of surface roughness, elasticity, cavitation, viscous and elastic fingering, substrate flexibility. PMID:21680396

  20. Improved Adhesion and Compliancy of Hierarchical Fibrillar Adhesives.

    PubMed

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

    2015-08-01

    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. PMID:26167951

  1. Effect of adhesive thickness on adhesively bonded T-joint

    NASA Astrophysics Data System (ADS)

    Abdullah, A. R.; Afendi, Mohd; Majid, M. S. Abdul

    2013-12-01

    The aim of this work is to analyze the effect of adhesive thickness on tensile strength of adhesively bonded stainless steel T-joint. Specimens were made from SUS 304 Stainless Steel plate and SUS 304 Stainless Steel perforated plate. Four T-joint specimens with different adhesive thicknesses (0.5, 1.0, 1.5 and 2.0 mm) were made. Experiment result shows T-joint specimen with adhesive thickness of 1.0 mm yield highest maximum load. Identical T-joint specimen jointed by spot welding was also tested. Tensile test shows welded T-Joint had eight times higher tensile load than adhesively bonded T-joint. However, in low pressure application such as urea granulator chamber, high tensile strength is not mandatory. This work is useful for designer in fertilizer industry and others who are searching for alternative to spot welding.

  2. Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes

    PubMed Central

    Strazza, Marianne; Azoulay-Alfaguter, Inbar; Pedoeem, Ariel; Mor, Adam

    2014-01-01

    T lymphocyte adhesion is required for multiple T cell functions, including migration to sites of inflammation and formation of immunological synapses with antigen presenting cells. T cells accomplish regulated adhesion by controlling the adhesive properties of integrins, a class of cell adhesion molecules consisting of heterodimeric pairs of transmembrane proteins that interact with target molecules on partner cells or extracellular matrix. The most prominent T cell integrin is lymphocyte function associated antigen (LFA)-1, composed of subunits αL and β2, whose target is the intracellular adhesion molecule (ICAM)-1. The ability of a T cell to control adhesion derives from the ability to regulate the affinity states of individual integrins. Inside-out signaling describes the process whereby signals inside a cell cause the external domains of integrins to assume an activated state. Much of our knowledge of these complex phenomena is based on mechanistic studies performed in simplified in vitro model systems. The T lymphocyte adhesion assay described here is an excellent tool that allows T cells to adhere to target molecules, under static conditions, and then utilizes a fluorescent plate reader to quantify adhesiveness. This assay has been useful in defining adhesion-stimulatory or inhibitory substances that act on lymphocytes, as well as characterizing the signaling events involved. Although described here for LFA-1 - ICAM-1 mediated adhesion; this assay can be readily adapted to allow for the study of other adhesive interactions (e.g. VLA-4 - fibronectin). PMID:24961998

  3. Postherpetic pseudohernia: delayed onset of paresis of abdominal muscles due to herpes zoster causing an ipsilateral abdominal bulge.

    PubMed

    Ohno, Shunsuke; Togawa, Yasuhiro; Chiku, Tsuyoshi; Sano, Wataru

    2016-01-01

    Postherpetic pseudohernia causes an abdominal bulge as well as an abdominal wall herniation. This disease is one of the neurological complications of herpes zoster and essentially consists of paresis of ipsilateral abdominal muscles. Postherpetic pseudohernia may be mistaken for abdominal wall herniation because it is not well known. We describe two cases presenting an abdominal bulge. The ipsilateral abdominal bulge appeared after recovery from abdominal zoster. Abdominal CT showed no evidence of a herniation or mass. We diagnosed a postherpetic pseudohernia. One of the patients recovered spontaneously 4 months after the onset, and the other partially recovered after 2 months. This disease can be expected to disappear spontaneously, unlike abdominal herniation requiring surgery. It has been reported that 79.3% of patients eventually recovered spontaneously. For surgeons and general practitioners, it is beneficial to keep this disease in mind when examining a patient presenting an abdominal bulge. PMID:27229900

  4. General Considerations of Ruptured Abdominal Aortic Aneurysm: Ruptured Abdominal Aortic Aneurysm

    PubMed Central

    Lee, Chung Won; Bae, Miju; Chung, Sung Woon

    2015-01-01

    Although development of surgical technique and critical care, ruptured abdominal aortic aneurysm still carries a high mortality. In order to obtain good results, various efforts have been attempted. This paper reviews initial management of ruptured abdominal aortic aneurysm and discuss the key point open surgical repair and endovascular aneurysm repair. PMID:25705591

  5. Platelet adhesiveness in diabetes mellitus

    PubMed Central

    Shaw, S.; Pegrum, G. D.; Wolff, Sylvia; Ashton, W. L.

    1967-01-01

    Platelet adhesiveness has been assessed on whole blood from a series of 34 diabetics and 50 control subjects using adenosine diphosphate (A.D.P.) and by adherence to glass microspherules (ballotini). Using both techniques it was possible to demonstrate a significant increase in platelet adhesiveness in the diabetic patients. PMID:5614070

  6. Measuring Adhesion And Friction Forces

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa

    1991-01-01

    Cavendish balance adapted to new purpose. Apparatus developed which measures forces of adhesion and friction between specimens of solid materials in vacuum at temperatures from ambient to 900 degrees C. Intended primarily for use in studying adhesion properties of ceramics and metals, including silicon carbide, aluminum oxide, and iron-base amorphous alloys.

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. Biological adhesives and fastening devices

    NASA Astrophysics Data System (ADS)

    Wolpert, H. D.

    2012-04-01

    Sea creatures are a leading source to some of the more interesting discoveries in adhesives. Because sea water naturally breaks down even the strongest conventional adhesive, an alternative is important that could be used in repairing or fabricating anything that might have regular contact with moisture such as: Repairing broken and shattered bones, developing a surgical adhesive, use in the dental work, repairing and building ships, and manufacturing plywood. Some of nature's prototypes include the common mussel, limpet, some bacteria and abalone. As we learn more about these adhesives we are also developing non adhesive fasteners, such as mimicked after studying the octopus, burdock burrs (i.e. Velcro®) and the gecko.

  13. Hyaluronan-mediated cellular adhesion

    NASA Astrophysics Data System (ADS)

    Curtis, Jennifer

    2005-03-01

    Many cells surround themselves with a cushioning halo of polysaccharides that is further strengthened and organized by proteins. In fibroblasts and chrondrocytes, the primary component of this pericellular matrix is hyaluronan, a large linear polyanion. Hyaluronan production is linked to a variety of disease, developmental, and physiological processes. Cells manipulate the concentration of hyaluronan and hyaluronan receptors for numerous activities including modulation of cell adhesion, cell motility, and differentiation. Recent investigations by identify hyaluronan's role in mediating early-stage cell adhesion. An open question is how the cell removes the 0.5-10 micron thick pericellular matrix to allow for further mature adhesion events requiring nanometer scale separations. In this investigation, holographic optical tweezers are used to study the adhesion and viscoelastic properties of chondrocytes' pericellular matrix. Ultimately, we aim to shed further light on the spatial and temporal details of the dramatic transition from micron to nanometer gaps between the cell and its adhesive substrate.

  14. Corrugated pipe adhesive applicator apparatus

    DOEpatents

    Shirey, Ray A.

    1983-06-14

    Apparatus for coating selected portions of the troughs of a corrugated pipe within an adhesive includes a support disposed within the pipe with a reservoir containing the adhesive disposed on the support. A pump, including a spout, is utilized for supplying the adhesive from the reservoir to a trough of the pipe. A rotatable applicator is supported on the support and contacts the trough of the pipe. The applicator itself is sized so as to fit within the trough, and contacts the adhesive in the trough and spreads the adhesive in the trough upon rotation. A trough shield, supported by the support and disposed in the path of rotation of the applicator, is utilized to prevent the applicator from contacting selected portions of the trough. A locator head is also disposed on the support and provides a way for aligning the spout, the applicator, and the trough shield with the trough.

  15. Corrugated pipe adhesive applicator apparatus

    DOEpatents

    Shirey, R.A.

    1983-06-14

    Apparatus for coating selected portions of the troughs of a corrugated pipe with an adhesive includes a support disposed within the pipe with a reservoir containing the adhesive disposed on the support. A pump, including a spout, is utilized for supplying the adhesive from the reservoir to a trough of the pipe. A rotatable applicator is supported on the support and contacts the trough of the pipe. The applicator itself is sized so as to fit within the trough, and contacts the adhesive in the trough and spreads the adhesive in the trough upon rotation. A trough shield, supported by the support and disposed in the path of rotation of the applicator, is utilized to prevent the applicator from contacting selected portions of the trough. A locator head is also disposed on the support and provides a way for aligning the spout, the applicator, and the trough shield with the trough. 4 figs.

  16. Adhesion testing device

    NASA Technical Reports Server (NTRS)

    LaPeyronnie, Glenn M. (Inventor); Huff, Charles M. (Inventor)

    2010-01-01

    The present invention provides a testing apparatus and method for testing the adhesion of a coating to a surface. The invention also includes an improved testing button or dolly for use with the testing apparatus and a self aligning button hook or dolly interface on the testing apparatus. According to preferred forms, the apparatus and method of the present invention are simple, portable, battery operated rugged, and inexpensive to manufacture and use, are readily adaptable to a wide variety of uses, and provide effective and accurate testing results. The device includes a linear actuator driven by an electric motor coupled to the actuator through a gearbox and a rotatable shaft. The electronics for the device are contained in the head section of the device. At the contact end of the device, is positioned a self aligning button hook, attached below the load cell located on the actuator shaft.

  17. Epidural lysis of adhesions.

    PubMed

    Lee, Frank; Jamison, David E; Hurley, Robert W; Cohen, Steven P

    2014-01-01

    As our population ages and the rate of spine surgery continues to rise, the use epidural lysis of adhesions (LOA) has emerged as a popular treatment to treat spinal stenosis and failed back surgery syndrome. There is moderate evidence that percutaneous LOA is more effective than conventional ESI for both failed back surgery syndrome, spinal stenosis, and lumbar radiculopathy. For cervical HNP, cervical stenosis and mechanical pain not associated with nerve root involvement, the evidence is anecdotal. The benefits of LOA stem from a combination of factors to include the high volumes administered and the use of hypertonic saline. Hyaluronidase has been shown in most, but not all studies to improve treatment outcomes. Although infrequent, complications are more likely to occur after epidural LOA than after conventional epidural steroid injections. PMID:24478895

  18. Epidural Lysis of Adhesions

    PubMed Central

    Lee, Frank; Jamison, David E.; Hurley, Robert W.

    2014-01-01

    As our population ages and the rate of spine surgery continues to rise, the use epidural lysis of adhesions (LOA) has emerged as a popular treatment to treat spinal stenosis and failed back surgery syndrome. There is moderate evidence that percutaneous LOA is more effective than conventional ESI for both failed back surgery syndrome, spinal stenosis, and lumbar radiculopathy. For cervical HNP, cervical stenosis and mechanical pain not associated with nerve root involvement, the evidence is anecdotal. The benefits of LOA stem from a combination of factors to include the high volumes administered and the use of hypertonic saline. Hyaluronidase has been shown in most, but not all studies to improve treatment outcomes. Although infrequent, complications are more likely to occur after epidural LOA than after conventional epidural steroid injections. PMID:24478895

  19. [Retention of adhesive bridges].

    PubMed

    Raes, F; De Boever, J

    1994-04-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rests, interocclusal clearance and cingulum stops is equally important. Including more teeth in the design does not necessarily lead to an improved retention. Besides the material and technical aspects, the whole clinical procedure needs much attention. The retention does not depend on one single factor, but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 80% can be obtained. PMID:11830965

  20. Development of Screenable Pressure Sensitive Adhesives

    SciTech Connect

    Steven J. Severtson

    2003-11-29

    An industrial research area of high activity in recent years has been the development of pressure sensitive adhesive (PSA) products that do not interfere with the processing of post-consumer waste. The problem of PSA contamination is arguably the most important technical challenge in expanding the use of recycled fiber. The presence of PSAs in recovered paper creates problems that reduce the efficiency of recycling and papermaking operations and diminish product quality. The widespread use of PSAs engineered to avoid these problems, often referred to as environmentally benign PSAs, could greatly increase the commercial viability of utilizing secondary fiber. Much of the research efforts in this area have focused on the development of PSAs that are designed for enhanced removal with cleaning equipment currently utilized by recycling plants. Most removal occurs at the pressure screens with the size and shape of residual contaminants in the process being the primary criteria for their separation. A viable approach for developing environmentally benign PSAs is their reformulation to inhibit fragmentation. The reduction of adhesives to small particles occurs almost exclusively during repulping; a process in which water and mechanical energy are used to swell and reduce paper products to their constituent fiber. Engineering PSA products to promote the formation of larger adhesive particles during repulping will greatly enhance their removal and reduce or eliminate their impact on the recycling process.

  1. Bacterial Adhesion: Seen Any Good Biofilms Lately?

    PubMed Central

    Dunne, W. Michael

    2002-01-01

    The process of surface adhesion and biofilm development is a survival strategy employed by virtually all bacteria and refined over millions of years. This process is designed to anchor microorganisms in a nutritionally advantageous environment and to permit their escape to greener pastures when essential growth factors have been exhausted. Bacterial attachment to a surface can be divided into several distinct phases, including primary and reversible adhesion, secondary and irreversible adhesion, and biofilm formation. Each of these phases is ultimately controlled by the expression of one or more gene products. Ultrastructurally, the mature bacterial biofilm resembles an underwater coral reef containing pyramidal or mushroom-shaped microcolonies of organisms embedded within an extracellular glycocalyx, with channels and cavities to allow the exchange of nutrients and waste. The biofilm protects its inhabitants from predators, dehydration, biocides, and other environmental extremes while regulating population growth and diversity through primitive cell signals. From a physiological standpoint, surface-bound bacteria behave quite differently from their planktonic counterparts. Recognizing that bacteria naturally occur as surface-bound and often polymicrobic communities, the practice of performing antimicrobial susceptibility tests using pure cultures and in a planktonic growth mode should be questioned. That this model does not reflect conditions found in nature might help explain the difficulties encountered in the management and treatment of biomedical implant infections. PMID:11932228

  2. The thoracic anterior spinal cord adhesion syndrome

    PubMed Central

    Taylor, T R; Dineen, R; White, B; Jaspan, T

    2012-01-01

    Objectives This study included a series of middle-aged male and female patients who presented with chronic anterior hemicord dysfunction progressing to paraplegia. Imaging of anterior thoracic cord displacement by either a dural adhesion or a dural defect with associated cord herniation is presented. Methods This is a retrospective review of cases referred to a tertiary neuroscience centre over a 19-year period. Imaging series were classified by two experienced neuroradiologists against several criteria and correlated with clinical examination and/or findings at surgery. Results 16 cases were available for full review. Nine were considered to represent adhesions (four confirmed surgically) and four to represent true herniation (three confirmed surgically). In the three remaining cases the diagnosis was radiologically uncertain. Conclusion The authors propose “thoracic anterior spinal cord adhesion syndrome” as a novel term to describe this patient cohort and suggest appropriate clinicoradiological features for diagnosis. Several possible aetiologies are also suggested, with disc rupture and inflammation followed by disc resorption and dural pocket formation being a possible mechanism predisposing to herniation at the extreme end of a clinicopathological spectrum. PMID:22665931

  3. Effect of fibril shape on adhesive properties

    NASA Astrophysics Data System (ADS)

    Soto, Daniel; Hill, Ginel; Parness, Aaron; Esparza, Noé; Cutkosky, Mark; Kenny, Tom

    2010-08-01

    Research into the gecko's adhesive system revealed a unique architecture for adhesives using tiny hairs. By using a stiff material (β-keratin) to create a highly structured adhesive, the gecko's system demonstrates properties not seen in traditional pressure-sensitive adhesives which use a soft, unstructured planar layer. In contrast to pressure sensitive adhesives, the gecko adhesive displays frictional adhesion, in which increased shear force allows it to withstand higher normal loads. Synthetic fibrillar adhesives have been fabricated but not all demonstrate this frictional adhesion property. Here we report the dual-axis force testing of single silicone rubber pillars from synthetic adhesive arrays. We find that the shape of the adhesive pillar dictates whether frictional adhesion or pressure-sensitive behavior is observed. This work suggests that both types of behavior can be achieved with structures much larger than gecko terminal structures. It also indicates that subtle differences in the shape of these pillars can significantly influence their properties.

  4. Functional bowel disorders and functional abdominal pain

    PubMed Central

    Thompson, W; Longstreth, G; Drossman, D; Heaton, K; Irvine, E; Muller-Lissner, S

    1999-01-01

    The Rome diagnostic criteria for the functional bowel disorders and functional abdominal pain are used widely in research and practice. A committee consensus approach, including criticism from multinational expert reviewers, was used to revise the diagnostic criteria and update diagnosis and treatment recommendations, based on research results. The terminology was clarified and the diagnostic criteria and management recommendations were revised. A functional bowel disorder (FBD) is diagnosed by characteristic symptoms for at least 12 weeks during the preceding 12 months in the absence of a structural or biochemical explanation. The irritable bowel syndrome, functional abdominal bloating, functional constipation, and functional diarrhea are distinguished by symptom-based diagnostic criteria. Unspecified FBD lacks criteria for the other FBDs. Diagnostic testing is individualized, depending on patient age, primary symptom characteristics, and other clinical and laboratory features. Functional abdominal pain (FAP) is defined as either the FAP syndrome, which requires at least six months of pain with poor relation to gut function and loss of daily activities, or unspecified FAP, which lacks criteria for the FAP syndrome. An organic cause for the pain must be excluded, but aspects of the patient's pain behavior are of primary importance. Treatment of the FBDs relies upon confident diagnosis, explanation, and reassurance. Diet alteration, drug treatment, and psychotherapy may be beneficial, depending on the symptoms and psychological features.


Keywords: functional bowel disorder; functional constipation; functional diarrhea; irritable bowel syndrome; functional abdominal pain; functional abdominal bloating; Rome II PMID:10457044

  5. Focal Adhesion of Osteoblastic Cells on Titanium Surface with Amine Functionalities Formed by Plasma Polymerization

    NASA Astrophysics Data System (ADS)

    Song, Heesang; Jung, Sang Chul; Kim, Byung Hoon

    2012-08-01

    To enhance the focal adhesion of osteoblastic cells on a titanium surface, plasma polymerized allyl amine (AAm) thin films were deposited by plasma polymerization. This plasma polymer functionalization of titanium is advantageous for osteoblastic focal adhesion formation. Such Ti surfaces are useful for the fabrication of titanium-based dental implants for enhancement of osseointegration.

  6. Immune T lymphocyte to tumor cell adhesion. Magnesium sufficient, calcium insufficient

    PubMed Central

    1980-01-01

    The prelytic adhesion of immune cytolytic thymus-derived lymphocytes to specific antigen-bearing ascites tumor target cells has been studied. A new assay was used in which adhesions are permitted to form for 2.5 min; the cells are then dispersed to prevent further adhesion, and the predispersion adhesions are quantitated by subsequent 51Cr release from the tumor cells as a result of cytolytic activity of the adhering lymphocytes. There were the following new findings: (a) magnesium is sufficient to support optimal adhesion formation even when EGTA is added to remove contaminating traces of calcium; (b) calcium supports no adhesion formation when traces of contaminating magnesium are removed by pretreating the medium with a chelating ion exchange resin; (c) calcium synergizes with suboptimal magnesium, increasing the apparent adhesion-supporting potency of magnesium 20-fold in the presence of 50 microM calcium; (d) in the presence of optimal magnesium (2--4 mM), calcium has not effect on the properties of the adhesion by any of six criteria; and (e) manganese supports adhesion better than magnesium, and strontium is ineffective. A survey of previous literature indicates that these results are remarkably similar to the predominant pattern for nonimmunologic cell adhesion (e.g., fibroblasts) involving cells from a variety of tissues in late embryonic and adult avians and mammals. This suggests that a "magnesium sufficient, calcium insufficient" mechanism may be found among the latter types of cell adhesions when appropriately examined. Moreover, it seems that the present lymphocyte-tumor cell adhesion, although evoked by specific receptor-antigen recognition, relies predominantly on mechanisms common to nonimmunologic intercellular adhesion processes. PMID:6766945

  7. Tunicate-mimetic nanofibrous hydrogel adhesive with improved wet adhesion.

    PubMed

    Oh, Dongyeop X; Kim, Sangsik; Lee, Dohoon; Hwang, Dong Soo

    2015-07-01

    The main impediment to medical application of biomaterial-based adhesives is their poor wet adhesion strength due to hydration-induced softening and dissolution. To solve this problem, we mimicked the wound healing process found in tunicates, which use a nanofiber structure and pyrogallol group to heal any damage on its tunic under sea water. We fabricated a tunicate-mimetic hydrogel adhesive based on a chitin nanofiber/gallic acid (a pyrogallol acid) composite. The pyrogallol group-mediated cross-linking and the nanofibrous structures improved the dissolution resistance and cohesion strength of the hydrogel compared to the amorphous polymeric hydrogels in wet condition. The tunicate-mimetic adhesives showed higher adhesion strength between fully hydrated skin tissues than did fibrin glue and mussel-mimetic adhesives. The tunicate mimetic hydrogels were produced at low cost from recyclable and abundant raw materials. This tunicate-mimetic adhesive system is an example of how natural materials can be engineered for biomedical applications. PMID:25841348

  8. Adequacy and quality of abdominal echographies requested by primary care professionals

    PubMed Central

    2010-01-01

    Background The value of abdominal echography in primary care is great because it is innocuous, inexpensive, easy to perform and provides a great deal of information making this the first examination to be requested in cases of probable abdominal disease. However, too many abdominal echographies are probably requested overcrowding the Departments of Radiodiagnosis with not always justified petitions or with repetition of tests based on little clinical criteria. Methods/Design The aim of the study is to evaluate the adequacy and quality of abdominal echographies requested by primary care physicians in the Maresme County (North of Barcelona), develop guidelines for indicating echographies and reevaluate this adequacy after implementing these guidelines. We will perform a two-phase study: the first descriptive, and retrospective evaluating the adequacy and quality of petitions for abdominal echographies, and in the second phase we will evaluate the impact of recommendations for indicating abdominal echographies for PC physicians on the adequacy and quality of echography petitions thereafter. This study will be carried out in 10 primary care centres in the Maresme (Barcelona). 1067 abdominal echographies requested by primary care physicians from the above mentioned centres from January 2007 to April 2010 and referred to the Department of Radiology and the same number of applications after the intervention. All the petitions for abdominal echographies requested will be analysed and the clinical histories will be obtained to determine demographic variables, the reason for the visit and for the echography petition and diagnostic orientation, clinical and echographic data, evaluation of the echographies according to the quality and variables characterising the professionals requesting the echographies including: age, sex, laboral situation, length of time in work post, formation, etc. To achieve a consensus of the adequacy of abdominal echography, a work group including

  9. Thoracic and abdominal blastomycosis in a horse.

    PubMed

    Toribio, R E; Kohn, C W; Lawrence, A E; Hardy, J; Hutt, J A

    1999-05-01

    A 5-year-old Quarter Horse mare was examined because of lethargy, fever, and weight loss of 1 month's duration. Thoracic auscultation revealed decreased lung sounds cranioventrally. Thoracic ultrasonography revealed bilateral anechoic areas with hyperechoic strands, consistent with pleural effusion and fibrin tags. A large amount of free fluid was evident during abdominal ultrasonography. Abnormalities included anemia, hyperproteinemia, hyperglobulinemia, hyperfibrinogenemia, and hypoalbuminemia. Thoracic radiography revealed alveolar infiltrates in the cranial and caudoventral lung fields. A cavitary mass, consistent with an abscess, could be seen caudodorsal to the crura of the diaphragm. Ultrasonographic evaluation of this area revealed a hypoechoic mass with septations. Bilateral thoracocentesis was performed. Bacterial culture of the pleural fluid did not yield growth, but Blastomyces dermatitidis was isolated from pleural fluid, abdominal fluid, and an aspirate of the abscess. The mare was euthanatized, and a diagnosis of thoracic and abdominal blastomycosis was confirmed at necropsy. PMID:10319179

  10. [Differential diagnosis of abdominal cysts in children].

    PubMed

    Józsa, Gergő; Mohay, Gabriella; Pintér, András; Vástyán, Attila

    2015-09-13

    19 children were diagnosed with abdominal cysts of different origin in the Surgical Unit of the Department of Pediatrics, Medical University of Pécs, Hungary between 2010 and 2013. The authors discuss the details of representative cases of a parovarial cyst, an intestinal duplication, and an omental cyst with emphasis on the clinical symptoms, diagnostic tools, and surgical interventions. The authors conclude that abdominal cysts often cause mild symptoms only, and they are discovered accidentally by ultrasound imaging performed for other reasons. In some cases, the cyst can cause severe complaints or even acute abdomen requiring emergency surgery. Laporoscopy may be a valuable method both in diagnosis and surgical therapy. Abdominal CT or MRI are not required in the majority of the patients. PMID:26552027

  11. [Abdominal splenosis: an often underdiagnosed entity].

    PubMed

    Vercher-Conejero, J L; Bello-Arqués, P; Pelegrí-Martínez, L; Hervás-Benito, I; Loaiza-Góngora, J L; Falgas-Lacueva, M; Ruiz-Llorca, C; Pérez-Velasco, R; Mateo-Navarro, A

    2011-01-01

    Splenosis is defined as the heterotopic autotransplantation of splenic tissue because of a ruptured spleen due to trauma or surgery. It is a benign and incidental finding, although imaging tests may sometimes orient toward malignancy simulating renal tumors, abdominal lymphomas, endometriosis, among other. We report the case of a 42-year old male in whom a MRI was performed after a study due to abdominal pain. Multiple enlarged lymph nodes were observed in the abdomen, suggestive of lymphoproliferative disease. As an important background, splenectomy was carried out due to abdominal trauma at age 9. After several studies, it was decided to perform a (99m)Tc-labeled heat-damaged red blood cell scintigraphy that showed multiple pathological deposits distributed throughout the abdomen, and even the pelvis, being consistent with splenosis. PMID:20570413

  12. [Abdominal aortic aneurysm and renovascular disease].

    PubMed

    Riambau, Vicente; Guerrero, Francisco; Montañá, Xavier; Gilabert, Rosa

    2007-06-01

    Recent technological advances in the diagnosis and therapy of abdominal aortic aneurysm and renovascular disease are continuing to bring about changes in the way patients suffering from these conditions are treated. The prevalence of both these conditions is increasing. This is due to greater life-expectancy in patients with arteriosclerosis, a pathogenetic factor underlying both conditions. The application of diagnostic imaging techniques to non-vascular conditions has led to the early diagnosis of abdominal aortic aneurysm. Clinical suspicion of reno-vascular disease can be confirmed easily using high-resolution diagnostic imaging modalities such as CT angiography and magnetic resonance angiography. Endovascular intervention is successfully replacing conventional surgical repair techniques, with the result that it may be possible to improve outcome in both conditions using effective and minimally invasive approaches. Future technological developments will enable these endovascular techniques to be applied in the large majority of patients with abdominal aortic aneurysm or renovascular disease. PMID:17580053

  13. Bioprosthetic Mesh in Abdominal Wall Reconstruction

    PubMed Central

    Baumann, Donald P.; Butler, Charles E.

    2012-01-01

    Mesh materials have undergone a considerable evolution over the last several decades. There has been enhancement of biomechanical properties, improvement in manufacturing processes, and development of antiadhesive laminate synthetic meshes. The evolution of bioprosthetic mesh materials has markedly changed our indications and methods for complex abdominal wall reconstruction. The authors review the optimal properties of bioprosthetic mesh materials, their evolution over time, and their indications for use. The techniques to optimize outcomes are described using bioprosthetic mesh for complex abdominal wall reconstruction. Bioprosthetic mesh materials clearly have certain advantages over other implantable mesh materials in select indications. Appropriate patient selection and surgical technique are critical to the successful use of bioprosthetic materials for abdominal wall repair. PMID:23372454

  14. Flap Coverage of Anterior Abdominal Wall Defects

    PubMed Central

    Sacks, Justin M.; Broyles, Justin M.; Baumann, Donald P.

    2012-01-01

    Reconstruction of complex defects of the anterior abdomen is both challenging and technically demanding for reconstructive surgeons. Advancements in the use of pedicle and free tissue transfer along with the use of bioprosthetic and synthetic meshes have provided for novel approaches to these complex defects. Accordingly, detailed knowledge of abdominal wall and lower extremity anatomy in combination with insight into the design, implementation, and limitations of various flaps is essential to solve these complex clinical problems. Although these defects can be attributed to a myriad of etiologic factors, the objectives in abdominal wall reconstruction are consistent and include the restoration of abdominal wall integrity, protection of intraabdominal viscera, and the prevention of herniation. In this article, the authors review pertinent anatomy and the various local, regional, and distant flaps that can be utilized in the reconstruction of these complex clinical cases of the anterior abdomen. PMID:23372457

  15. Abdominal aortic aneurysm--the forgotten diagnosis?

    PubMed Central

    Contini, S.; McMaster, P.

    1980-01-01

    A review of all cases of abdominal aortic aneurysm presenting to Addenbrooke's Hospital, Cambridge, in a 4-year period revealed that there were 118 such patients and confirmed the relatively low operative mortality for elective aneurysmal surgery (6.6%) compared with the high mortality (66.6%) for ruptured or leaking abdominal aneurysm. In only 50% of the cases was the correct diagnosis made during the lifetime of the patient; nor was the correct diagnosis always made after admission to hospital. The need for an early and accurate diagnosis of abdominal aneurysms is stressed and an increased awareness of this condition, based on well established clinical features, would undoubtedly reduce the overall mortality. Images Fig. 1 PMID:7393787

  16. [Pediatric Abdominal Pain – Harmless or Harmful?].

    PubMed

    Furlano, Raoul Ivano

    2016-04-27

    Abdominal pain is a very common pediatric complaint. In the majority of cases there is no life-threatening pathology behind this symptom, but a functional disease. However, all-day activities of children and adolescents are often limited, frequent absences from school, and general physician/ pediatrician office visits with often unnecessary diagnostic and therapies are registered. Once an organic etiology of the abdominal pain is excluded by a thoroughly medical history taking and physical examination, the first steps for a successful alleviation of the pain is the reassurance of the patients and their family that there is no life-threatening pathology. There is evidence that cognitive-behavioral therapy may be useful in improving pain and disability outcome in the short term. There is no evidence for pharmacological, dietetic, or complementary intervention in the treatment of chronic functional abdominal pain. PMID:27120211

  17. Wet Adhesion and Adhesive Locomotion of Snails on Anti-Adhesive Non-Wetting Surfaces

    PubMed Central

    Shirtcliffe, Neil J.; McHale, Glen; Newton, Michael I.

    2012-01-01

    Creating surfaces capable of resisting liquid-mediated adhesion is extremely difficult due to the strong capillary forces that exist between surfaces. Land snails use this to adhere to and traverse across almost any type of solid surface of any orientation (horizontal, vertical or inverted), texture (smooth, rough or granular) or wetting property (hydrophilic or hydrophobic) via a layer of mucus. However, the wetting properties that enable snails to generate strong temporary attachment and the effectiveness of this adhesive locomotion on modern super-slippy superhydrophobic surfaces are unclear. Here we report that snail adhesion overcomes a wide range of these microscale and nanoscale topographically structured non-stick surfaces. For the one surface which we found to be snail resistant, we show that the effect is correlated with the wetting response of the surface to a weak surfactant. Our results elucidate some critical wetting factors for the design of anti-adhesive and bio-adhesion resistant surfaces. PMID:22693563

  18. Adhesion enhancement of ion beam mixed Cu/Al/polyimide

    NASA Astrophysics Data System (ADS)

    Chang, G. S.; Jung, S. M.; Lee, Y. S.; Choi, I. S.; Whang, C. N.; Woo, J. J.; Lee, Y. P.

    1997-01-01

    Cu (400 Å)/polyimide was mixed with 80 keV Ar+ and N2+ from 1.0×1015 to 2.0×1016 ions/cm2. The same processes were repeated for the Cu (400 Å)/Al (50 Å)/polyimide system which has Al as a buffer layer. The quantitative adhesion strength was measured by a standard scratch test. X-ray photoelectron spectroscopy was employed to investigate the change in the chemical bonds of the ion beam mixed polyimide substrate and the intermediate effects for the adhesion enhancement in Cu/Al/polyimide. Two distinct tendencies are observed in the adhesion strength: Cu/Al/polyimide is more adhesive than Cu/polyimide after ion beam mixing, and N2+ ions are more effective in the adhesion enhancement than Ar+. The formation of an interlayer compound of CuAl2O4 accounts for the former, while the latter is understood by the fact that N2+ ions produce more pyridinelike moiety, amide group and tertiary amine moiety which are known as adhesion promoters.

  19. The glycocalyx promotes cooperative binding and clustering of adhesion receptors.

    PubMed

    Xu, Guang-Kui; Qian, Jin; Hu, Jinglei

    2016-05-18

    Cell adhesion plays a pivotal role in various biological processes, e.g., immune responses, cancer metastasis, and stem cell differentiation. The adhesion behaviors depend subtly on the binding kinetics of receptors and ligands restricted at the cell-substrate interfaces. Although much effort has been directed toward investigating the kinetics of adhesion molecules, the role of the glycocalyx, anchored on cell surfaces as an exterior layer, is still unclear. In this paper, we propose a theoretical approach to study the collective binding kinetics of a few and a large number of binders in the presence of the glycocalyx, representing the cases of initial and mature adhesions of cells, respectively. The analytical results are validated by finding good agreement with our Monte Carlo simulations. In the force loading case, the on-rate and affinity increase as more bonds form, whereas this cooperative effect is not observed in the displacement loading case. The increased thickness and stiffness of the glycocalyx tend to decrease the affinity for a few bonds, while they have less influence on the affinity for a large number of bonds. Moreover, for a flexible membrane with thermally-excited shape fluctuations, the glycocalyx is exhibited to promote the formation of bond clusters, mainly due to the cooperative binding of binders. This study helps to understand the cooperative kinetics of adhesion receptors under physiologically relevant loading conditions and sheds light on the novel role of the glycocalyx in cell adhesion. PMID:27102288

  20. [Preventive effect of changzhankang in experimental intestinal adhesions in rats].

    PubMed

    Wang, Y Q; Wei, J Q; Dai, D Z

    1991-08-01

    Intestinal adhesions were induced in rats by stabbing the terminal part of the ileum. Adhesion prevention by ibuprofen and changzhankang (CZK), which was composed by traditional Chinese medicines, was evaluated with a grading system. All of the 13 rats in the non-treated group created severe adhesions. The severity was significantly modified by orally administered CZK of 20 g/kg (in crude drugs) once or twice daily for five days (P less than 0.01 and P less than 0.05 compared with the non-treated). Intramuscular injection of ibuprofen (35 mg/kg, 3 times daily) also alleviated the severity of adhesions. There was no significant difference between the ibuprofen-treated and CZK-treated groups though some of the rats were virtually free from adhesion formation in the latter. It is plausible to expect CZK to become a promising drug used in treating intestinal adhesions, for the natural drug has greater security and less side effects than synthesized drugs. PMID:1954667

  1. Autosomal Mutations Affecting Adhesion between Wing Surfaces in Drosophila Melanogaster

    PubMed Central

    Prout, M.; Damania, Z.; Soong, J.; Fristrom, D.; Fristrom, J. W.

    1997-01-01

    Integrins are evolutionarily conserved transmembrane α,β heterodimeric receptors involved in cell-to-matrix and cell-to-cell adhesions. In Drosophila the position-specific (PS) integrins mediate the formation and maintenance of junctions between muscle and epidermis and between the two epidermal wing surfaces. Besides integrins, other proteins are implicated in integrin-dependent adhesion. In Drosophila, somatic clones of mutations in PS integrin genes disrupt adhesion between wing surfaces to produce wing blisters. To identify other genes whose products function in adhesion between wing surfaces, we conducted a screen for autosomal mutations that produce blisters in somatic wing clones. We isolated 76 independent mutations in 25 complementation groups, 15 of which contain more than one allele. Chromosomal sites were determined by deficiency mapping, and genetic interactions with mutations in the β(PS) integrin gene myospheroid were investigated. Mutations in four known genes (blistered, Delta, dumpy and mastermind) were isolated. Mutations were isolated in three new genes (piopio, rhea and steamer duck) that affect myo-epidermal junctions or muscle function in embryos. Mutations in three other genes (kakapo, kiwi and moa) may also affect cell adhesion or muscle function at hatching. These new mutants provide valuable material for the study of integrin-dependent cell-to-cell adhesion. PMID:9136017

  2. 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

  3. 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.

  4. Segmental Aortic Stiffening Contributes to Experimental Abdominal Aortic Aneurysm Development

    PubMed Central

    Raaz, Uwe; Zöllner, Alexander M.; Schellinger, Isabel N.; Toh, Ryuji; Nakagami, Futoshi; Brandt, Moritz; Emrich, Fabian C.; Kayama, Yosuke; Eken, Suzanne; Adam, Matti; Maegdefessel, Lars; Hertel, Thomas; Deng, Alicia; Jagger, Ann; Buerke, Michael; Dalman, Ronald L.; Spin, Joshua M.; Kuhl, Ellen; Tsao, Philip S.

    2015-01-01

    Background Stiffening of the aortic wall is a phenomenon consistently observed in age and in abdominal aortic aneurysm (AAA). However, its role in AAA pathophysiology is largely undefined. Methods and Results Using an established murine elastase-induced AAA model, we demonstrate that segmental aortic stiffening (SAS) precedes aneurysm growth. Finite element analysis (FEA) reveals that early stiffening of the aneurysm-prone aortic segment leads to axial (longitudinal) wall stress generated by cyclic (systolic) tethering of adjacent, more compliant wall segments. Interventional stiffening of AAA-adjacent aortic segments (via external application of surgical adhesive) significantly reduces aneurysm growth. These changes correlate with reduced segmental stiffness of the AAA-prone aorta (due to equalized stiffness in adjacent segments), reduced axial wall stress, decreased production of reactive oxygen species (ROS), attenuated elastin breakdown, and decreased expression of inflammatory cytokines and macrophage infiltration, as well as attenuated apoptosis within the aortic wall. Cyclic pressurization of segmentally stiffened aortic segments ex vivo increases the expression of genes related to inflammation and extracellular matrix (ECM) remodeling. Finally, human ultrasound studies reveal that aging, a significant AAA risk factor, is accompanied by segmental infrarenal aortic stiffening. Conclusions The present study introduces the novel concept of segmental aortic stiffening (SAS) as an early pathomechanism generating aortic wall stress and triggering aneurysmal growth, thereby delineating potential underlying molecular mechanisms and therapeutic targets. In addition, monitoring SAS may aid the identification of patients at risk for AAA. PMID:25904646

  5. The preventive effect of fish oil on abdominal aortic aneurysm development.

    PubMed

    Kugo, Hirona; Zaima, Nobuhiro; Mouri, Youhei; Tanaka, Hiroki; Yanagimoto, Kenichi; Urano, Tetsumei; Unno, Naoki; Moriyama, Tatsuya

    2016-06-01

    Abdominal aortic aneurysm (AAA) is a vascular disease involving gradual dilation of the abdominal aorta and high rupture-related mortality rates. AAA is histologically characterized by oxidative stress, chronic inflammation, and extracellular matrix degradation in the vascular wall. We previously demonstrated that aortic hypoperfusion could cause the vascular inflammation and AAA formation. However, the preventive method for hypoperfusion-induced AAA remains unknown. In this study, we evaluated the effect of fish oil on AAA development using a hypoperfusion-induced AAA animal model. Dilation of the abdominal aorta in the fish oil administration group was smaller than in the control group. Collagen destruction and oxidative stress were suppressed in the fish oil administration group than in the control group. These results suggested that fish oil could prevent the development of AAA induced by hypoperfusion. PMID:27022887

  6. Percutaneous treatment of abdominal coarctation in children using a covered stent.

    PubMed

    Pilati, Mara; Pongiglione, Giacomo; Gagliardi, M G

    2013-01-01

    Coarctation of the abdominal aorta is extremely rare. It generally involves a long segment of the descending aorta and causes uncontrolled and unexplainable hypertension in children. The therapeutic choice is very challenging because acute and chronic complications are reported for both the surgical and the percutaneous approaches. The two reported cases of abdominal coarctation were treated primarily and successfully through the use of covered stents. Three covered stents were implanted in two children. No complication occurred with either procedure. At this writing, an 18-month follow-up assessment has found the patients in good health with no restenosis at the coarctation site. Covered stent implantation in children with abdominal coarctation is a feasible, safe, and effective procedure. It provides adequate relief of symptoms and reduces the risk of aneurysm formation. To avoid covering important side branches with polytetrafluoroethylene, this type of procedure must be preceded by precise study of the aorta and its branches. PMID:23515761

  7. Marine Bioinspired Underwater Contact Adhesion.

    PubMed

    Clancy, Sean K; Sodano, Antonio; Cunningham, Dylan J; Huang, Sharon S; Zalicki, Piotr J; Shin, Seunghan; Ahn, B Kollbe

    2016-05-01

    Marine mussels and barnacles are sessile biofouling organisms that adhere to a number of surfaces in wet environments and maintain remarkably strong bonds. Previous synthetic approaches to mimic biological wet adhesive properties have focused mainly on the catechol moiety, present in mussel foot proteins (mfps), and especially rich in the interfacial mfps, for example, mfp-3 and -5, found at the interface between the mussel plaque and substrate. Barnacles, however, do not use Dopa for their wet adhesion, but are instead rich in noncatecholic aromatic residues. Due to this anomaly, we were intrigued to study the initial contact adhesion properties of copolymerized acrylate films containing the key functionalities of barnacle cement proteins and interfacial mfps, for example, aromatic (catecholic or noncatecholic), cationic, anionic, and nonpolar residues. The initial wet contact adhesion of the copolymers was measured using a probe tack testing apparatus with a flat-punch contact geometry. The wet contact adhesion of an optimized, bioinspired copolymer film was ∼15.0 N/cm(2) in deionized water and ∼9.0 N/cm(2) in artificial seawater, up to 150 times greater than commercial pressure-sensitive adhesive (PSA) tapes (∼0.1 N/cm(2)). Furthermore, maximum wet contact adhesion was obtained at ∼pH 7, suggesting viability for biomedical applications. PMID:27046671

  8. Chronic rupture of abdominal aortic aneurysm.

    PubMed

    Kotsis, Thomas; Thomas, Kotsis; Tympa, Aliki; Aliki, Tympa; Kalinis, Aris; Aris, Kalinis; Vasilopoulos, Ioannis; Ioannis, Vasilopoulos; Theodoraki, Kassiani; Kassiani, Theodoraki

    2011-10-01

    Although the mortality rate after abdominal aortic aneurysm rupture approximates 90% despite the urgent management, a few cases of chronic rupture and delayed repair have been reported in the world literature; anatomic and hemodynamic reasons occasionally allow for the fortunate course of these patients. We report in this article the case of 76-year-old man with a ruptured abdominal aortic aneurysm who was transferred to our facility 4 weeks after his initial hospitalization in a district institution and who finally had a successful open repair. PMID:21620664

  9. An unusual cause of abdominal pain.

    PubMed

    Terneu, S; Verhelst, D; Thys, F; Ketelslegers, E; Hantson, P; Wittebole, X

    2003-01-01

    A 36-year-old woman presented to the Emergency Room because of abdominal pain associated with hematuria and red blood blending to stool. On admission, the physical examination revealed abdominal tenderness and diffuse cutaneous hematoma. The laboratory findings showed abnormal clotting tests with high International Normalised Ratio (INR) and prolonged activated partial thromboplastin time. Hemoperitoneum and ureteral hematoma were noted on the abdomen computed tomography. The patient confessed she had ingested difenacoum for several weeks. All the symptoms resolved with fresh frozen plasma perfusion and vitamin K. PMID:14635532

  10. [Abdominal migraine as a cause of chronic recurrent abdominal pain in a 9-years-old girl--case report].

    PubMed

    Kwiecień, Jarosław; Piasecki, Leszek; Kasner, Jacek; Karczewska, Krystyna

    2005-08-01

    Abdominal migraine is a rarely recognized functional intestinal disorder, manifesting as recurrent paroxysmal abdominal pain of neurogenic origin. The authors describe the 9-years old girl referred to the hospital because of chronic paroxysmal abdominal pain. She did not improve after medication used commonly in functional abdominal disorders (drotaverine, mebeverine, trimebutine). On the ground of various investigations organic causes of abdominal pain were excluded. Carefully completed anamnesis, as well as precise description of the clinical picture of abdominal pain attacks, has lead to the diagnosis of abdominal migraine. According to advice of neurologist the treatment with amitriptyline was introduced. Thereafter a significant improvement was observed. Abdominal migraine has to be taken in to account when diagnosing chronic abdominal pain in children. PMID:16245431

  11. [Laparoscopic diagnosis and treatment of early adhesive small bowel obstruction after gynecological surgery].

    PubMed

    Timofeev, M E; Breusenko, V G; Shapoval'iants, S G; Fedorov, E D; Larichev, S E; Kretsu, V N

    2015-01-01

    It is presented the results of diagnostic and curative laparoscopic interventions in 33 patients with acute early adhesive small bowel obstruction. Ileus developed after surgical treatment (laparotomy) of different gynecological diseases. Laparoscopy appeared as the most informative diagnostic method to confirm diagnosis in all patients, to estimate state of abdominal cavity and small pelvis organs what can help to determine method of surgical treatment. Contraindications for laparoscopic surgery were identified in 12 (36.4%) patients and conversion to laparotomy was applied in this group. Postoperative complications were diagnosed in 1 (8.3%) patient. 2 (16.6%) patients died. Early adhesive ileus was resolved laparoscopically in 21 (63.6%) of 33 patients. Recurrent acute early adhesive ileus was detected in 1 (4.7%) patient. PMID:26031952

  12. Adhesion molecules in cutaneous inflammation.

    PubMed

    Barker, J N

    1995-01-01

    As in other organs, leukocyte adhesion molecules and their ligands play a major role in cutaneous inflammatory events both by directing leukocyte trafficking and by their effects on antigen presentation. Skin biopsies of inflamed skin from patients with diseases such as as psoriasis or atopic dermatitis reveal up-regulation of endothelial cell expression of P- and E-selectin, vascular cell adhesion molecule 1 and intercellular adhesion molecule 1. Studies of evolving lesions following UVB irradiation, Mantoux reaction or application of contact allergen, demonstrate that expression of these adhesion molecules parallels leukocyte infiltration into skin. When cutaneous inflammation is widespread (e.g. in erythroderma), soluble forms of these molecules are detectable in serum. In vitro studies predict that peptide mediators are important regulatory factors for endothelial adhesion molecules. Intradermal injection of the cytokines interleukin 1, tumour necrosis factor alpha and interferon gamma into normal human skin leads to induction of endothelial adhesion molecules with concomitant infiltration of leukocytes. In addition, neuropeptides rapidly induce P-selectin translocation to the cell membrane and expression of E-selectin. Adhesion molecules also play a crucial role as accessory molecules in the presentation of antigen to T lymphocytes by Langerhans' cells. Expression of selectin ligands by Langerhans' cells is up-regulated by various inflammatory stimuli, suggesting that adhesion molecules may be important in Langerhans' cell migration. The skin, because of its accessibility, is an ideal organ in which to study expression of adhesion molecules and their relationship to inflammatory events. Inflammatory skin diseases are common and inhibition of lymphocyte accumulation in skin is likely to prove of great therapeutic benefit. PMID:7587640

  13. Paragonimiasis mimicking chest cancer and abdominal wall metastaisis: A case report

    PubMed Central

    ZHOU, RONGXING; ZHANG, MINJIA; CHENG, NANSHENG; ZHOU, YONG

    2016-01-01

    Typical human paragonimiasis demonstrates an elevated eosinophil count, positive immunoblot, nodular shadows of the lung and pleural thickening with pleural effusion, and these symptoms may be confused with chest cancer. In the present case, a rare case of human paragonimiasis mimicking chest cancer and abdominal wall metastasis is described, the 39-year-old male patient was admitted in our hospital for cough, weight loss 5 kg and a firm mass in right upper abdominal wall. The laboratory test showed unremarkable hematology and biochemistry results. Chest X-ray, Plain computed tomography of the chest and abdomen showed right pleural effusion, several nodules in right lower lung and a mass in the right upper abdominal wall. The initial diagnosis was lung or chest cancer with abdominal wall metastasis, and the abdominal wall mass was resected for the final diagnosis. The biopsy revealed eosinophilic granuloma with Charcot-Leyden crystal formation infiltrated in the muscular fibers. Subsequent to assessment of the antibodies against parasites, the final diagnosis of paragonimiasis was made. PMID:27313691

  14. 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

  15. Adhesive Performance of Biomimetic Adhesive-Coated Biologic Scaffolds

    PubMed Central

    Murphy, John L.; Vollenweider, Laura; Xu, Fangmin; Lee, Bruce P.

    2010-01-01

    Surgical repair of a discontinuity in traumatized or degenerated soft tissues is traditionally accomplished using sutures. A current trend is to reinforce this primary repair with surgical grafts, meshes, or patches secured with perforating mechanical devices (i.e., sutures, staples, or tacks). These fixation methods frequently lead to chronic pain and mesh detachment. We developed a series of biodegradable adhesive polymers that are synthetic mimics of mussel adhesive proteins (MAPs), composed of 3,4-dihydroxyphenylalanine (DOPA)-derivatives, polyethylene glycol (PEG), and polycaprolactone (PCL). These polymers can be cast into films, and their mechanical properties, extent of swelling, and degradation rate can be tailored through the composition of the polymers as well as blending with additives. When coated onto a biologic mesh used for hernia repair, these adhesive constructs demonstrated adhesive strengths significantly higher than fibrin glue. With further development, a pre-coated bioadhesive mesh may represent a new surgical option for soft tissue repair. PMID:20919699

  16. Focal adhesion kinases in adhesion structures and disease.

    PubMed

    Eleniste, Pierre P; Bruzzaniti, Angela

    2012-01-01

    Cell adhesion to the extracellular matrix (ECM) is essential for cell migration, proliferation, and embryonic development. Cells can contact the ECM through a wide range of matrix contact structures such as focal adhesions, podosomes, and invadopodia. Although they are different in structural design and basic function, they share common remodeling proteins such as integrins, talin, paxillin, and the tyrosine kinases FAK, Pyk2, and Src. In this paper, we compare and contrast the basic organization and role of focal adhesions, podosomes, and invadopodia in different cells. In addition, we discuss the role of the tyrosine kinases, FAK, Pyk2, and Src, which are critical for the function of the different adhesion structures. Finally, we discuss the essential role of these tyrosine kinases from the perspective of human diseases. PMID:22888421

  17. Focal Adhesion Kinases in Adhesion Structures and Disease

    PubMed Central

    Eleniste, Pierre P.; Bruzzaniti, Angela

    2012-01-01

    Cell adhesion to the extracellular matrix (ECM) is essential for cell migration, proliferation, and embryonic development. Cells can contact the ECM through a wide range of matrix contact structures such as focal adhesions, podosomes, and invadopodia. Although they are different in structural design and basic function, they share common remodeling proteins such as integrins, talin, paxillin, and the tyrosine kinases FAK, Pyk2, and Src. In this paper, we compare and contrast the basic organization and role of focal adhesions, podosomes, and invadopodia in different cells. In addition, we discuss the role of the tyrosine kinases, FAK, Pyk2, and Src, which are critical for the function of the different adhesion structures. Finally, we discuss the essential role of these tyrosine kinases from the perspective of human diseases. PMID:22888421

  18. 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. PMID:26824739

  19. Prevention of Polyglycolic Acid-Induced Peritoneal Adhesions Using Alginate in a Rat Model

    PubMed Central

    Matoba, Mari; Hashimoto, Ayumi; Tanzawa, Ayumi; Orikasa, Taichi; Ikeda, Junki; Iwame, Yoshizumi; Ozamoto, Yuki; Miyamoto, Hiroe; Yoshida, Chiko; Hashimoto, Toru; Torii, Hiroko; Takamori, Hideki; Morita, Shinichiro; Tsujimoto, Hiroyuki; Hagiwara, Akeo

    2015-01-01

    Postoperative intra-abdominal or intrathoracic adhesions sometimes cause significant morbidity. We have designed three types of alginate-based treatments using strongly cross-linked (SL), weakly cross-linked (WL), and non-cross-linked (NL) alginate with calcium gluconate. In rat experiments, we compared the antiadhesive effects of the three types of alginate-based treatments, fibrin glue treatment (a standard treatment), and no treatment against adhesions caused by polyglycolic acid (PGA) mesh (PGA-induced adhesions). The antiadhesive materials were set on the PGA sheet fixed on the parietal peritoneum of the abdomen. Fifty-six days later, the adhesions were evaluated macroscopically by the adhesion scores and microscopically by hematoxylin-eosin staining and immunostaining. We also tested the fibroblast growth on the surface of the antiadhesive materials in vitro. The antiadhesive effects of WL and NL were superior to the no treatment and fibrin glue treatment. A microscopic evaluation confirmed that the PGA sheet was covered by a peritoneal layer constructed of well-differentiated mesothelial cells, and the inflammation was most improved in the NL and WL. The fibroblast growth was inhibited most on the surfaces of the NL and WL. These results suggest that either the WL or NL treatments are suitable for preventing PGA-induced adhesions compared to SL or the conventional treatment. PMID:26078949

  20. Endothelial cell proliferation and monocyte adhesion to atherosclerotic lesions of white carneau pigeons.

    PubMed Central

    Taylor, R. G.; Lewis, J. C.

    1986-01-01

    Two of the early changes that occur at sites of developing atherosclerotic lesions in pigeon aortas are monocyte adhesion and endothelial proliferation. We characterized these events in the abdominal aortas of lesion-free young pigeons and in mature birds that developed either naturally occurring or cholesterol-induced atherosclerosis. Compared with mature animals, very young (7-day-old) pigeons had elevated endothelial cell labeling with 3H-thymidine in normal regions of aorta as quantitated by scanning electron microscopy. All regions of atherosclerosis exhibited at least a fivefold increase in both monocyte adhesion and endothelial proliferation. Adhesion and proliferation were highest at the developing edge of lesions. When naturally occurring lesions of 5-year-old birds were compared with lesions of younger birds fed a 0.5% cholesterol-supplemented diet for either 15 or 52 weeks, monocyte adhesion and endothelial cell proliferation were found to be similar. The same parameters were studied after regression of atherosclerosis in pigeons fed 0.5% cholesterol-supplemented diet for 1 year, followed by cholesterol-free diet for 2, 6, or 11 months. The regression regimen resulted in significant reduction in both monocyte adhesion and endothelial proliferation at lesion sites. It is concluded that progressing atherosclerotic lesions, whether occurring naturally or exacerbated by cholesterol feeding, have similar and significant increases in monocyte adhesion and endothelial cell proliferation. Regression of atherosclerotic lesions is accompanied by a decrease in these two cellular events. Images Figure 1 Figure 2 PMID:3777132

  1. Homophilic Adhesion Mechanism of Neurofascin, a Member of the L1 Family of Neural Cell Adhesion Molecules

    SciTech Connect

    Liu, Heli; Focia, Pamela J.; He, Xiaolin

    2012-02-13

    The L1 family neural cell adhesion molecules play key roles in specifying the formation and remodeling of the neural network, but their homophilic interaction that mediates adhesion is not well understood. We report two crystal structures of a dimeric form of the headpiece of neurofascin, an L1 family member. The four N-terminal Ig-like domains of neurofascin form a horseshoe shape, akin to several other immunoglobulin superfamily cell adhesion molecules such as hemolin, axonin, and Dscam. The neurofascin dimer, captured in two crystal forms with independent packing patterns, reveals a pair of horseshoes in trans-synaptic adhesion mode. The adhesion interaction is mediated mostly by the second Ig-like domain, which features an intermolecular {beta}-sheet formed by the joining of two individual GFC {beta}-sheets and a large but loosely packed hydrophobic cluster. Mutagenesis combined with gel filtration assays suggested that the side chain hydrogen bonds at the intermolecular {beta}-sheet are essential for the homophilic interaction and that the residues at the hydrophobic cluster play supplementary roles. Our structures reveal a conserved homophilic adhesion mode for the L1 family and also shed light on how the pathological mutations of L1 affect its structure and function.

  2. Interfacial adhesion of carbon fibers

    NASA Technical Reports Server (NTRS)

    Bascom, Willard D.

    1987-01-01

    Relative adhesion strengths between AS4, AS1, and XAS carbon fibers and thermoplastic polymers were determined using the embedded single filament test. Polymers studied included polycarbonate, polyphenylene oxide, polyetherimide, polysulfone, polyphenylene oxide blends with polystyrene, and polycarbonate blends with a polycarbonate polysiloxane block copolymer. Fiber surface treatments and sizings improved adhesion somewhat, but adhesion remained well below levels obtained with epoxy matrices. An explanation for the differences between the Hercules and Grafil fibers was sought using X ray photon spectroscopy, wetting, scanning electron microscopy and thermal desorption analysis.

  3. Notch-Mediated Cell Adhesion.

    PubMed

    Murata, Akihiko; Hayashi, Shin-Ichi

    2016-01-01

    Notch family members are generally recognized as signaling molecules that control various cellular responses in metazoan organisms. Early fly studies and our mammalian studies demonstrated that Notch family members are also cell adhesion molecules; however, information on the physiological roles of this function and its origin is limited. In this review, we discuss the potential present and ancestral roles of Notch-mediated cell adhesion in order to explore its origin and the initial roles of Notch family members dating back to metazoan evolution. We hypothesize that Notch family members may have initially emerged as cell adhesion molecules in order to mediate multicellularity in the last common ancestor of metazoan organisms. PMID:26784245

  4. Photovoltaic module with adhesion promoter

    SciTech Connect

    Xavier, Grace

    2013-10-08

    Photovoltaic modules with adhesion promoters and methods for fabricating photovoltaic modules with adhesion promoters are described. A photovoltaic module includes a solar cell including a first surface and a second surface, the second surface including a plurality of interspaced back-side contacts. A first glass layer is coupled to the first surface by a first encapsulating layer. A second glass layer is coupled to the second surface by a second encapsulating layer. At least a portion of the second encapsulating layer is bonded directly to the plurality of interspaced back-side contacts by an adhesion promoter.

  5. Notch-Mediated Cell Adhesion

    PubMed Central

    Murata, Akihiko; Hayashi, Shin-Ichi

    2016-01-01

    Notch family members are generally recognized as signaling molecules that control various cellular responses in metazoan organisms. Early fly studies and our mammalian studies demonstrated that Notch family members are also cell adhesion molecules; however, information on the physiological roles of this function and its origin is limited. In this review, we discuss the potential present and ancestral roles of Notch-mediated cell adhesion in order to explore its origin and the initial roles of Notch family members dating back to metazoan evolution. We hypothesize that Notch family members may have initially emerged as cell adhesion molecules in order to mediate multicellularity in the last common ancestor of metazoan organisms. PMID:26784245

  6. Adhesives from modified soy protein

    DOEpatents

    Sun, Susan; Wang, Donghai; Zhong, Zhikai; Yang, Guang

    2008-08-26

    The, present invention provides useful adhesive compositions having similar adhesive properties to conventional UF and PPF resins. The compositions generally include a protein portion and modifying ingredient portion selected from the group consisting of carboxyl-containing compounds, aldehyde-containing compounds, epoxy group-containing compounds, and mixtures thereof. The composition is preferably prepared at a pH level at or near the isoelectric point of the protein. In other preferred forms, the adhesive composition includes a protein portion and a carboxyl-containing group portion.

  7. Advances in light curing adhesives

    NASA Astrophysics Data System (ADS)

    Bachmann, Andy

    2001-11-01

    This paper describes the development of a new family of light curing adhesives containing a new reactive additive previously not used in optical grade light curing adhesives are obtained with the addition of functionalized cellulositics. Outgassing as low as 10-6 grams/gram has been observed based on headspace sampling. Other additives have lowered the shrinkage rates of positioning adhesives from near 1 percent to less than 0.1 percent with fractional, percentage movements over thermal range of -40 degrees C to +200 degrees C.

  8. 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. PMID:19833509

  9. 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. PMID:23886969

  10. Adhesion and non-linear rheology of adhesives with supramolecular crosslinking points.

    PubMed

    Callies, X; Fonteneau, C; Pensec, S; Bouteiller, L; Ducouret, G; Creton, C

    2016-09-14

    Soft supramolecular materials are promising for the design of innovative and highly tunable adhesives. These materials are composed of polymer chains functionalized by strongly interacting moieties, sometimes called "stickers". In order to systematically investigate the effect of the presence of associative groups on the debonding properties of a supramolecular adhesive, a series of supramolecular model systems has been characterized by probe-tack tests. These model materials, composed of linear and low dispersity poly(butylacrylate) chains functionalized in the middle by a single tri-urea sticker, are able to self-associate by six hydrogen bonds and range in molecular weight (Mn) between 5 and 85 kg mol(-1). The linear rheology and the nanostructure of the same materials (called "PnBA3U") were the object of a previous study. At room temperature, the association of polymers via hydrogen bonds induces the formation of rod-like aggregates structured into bundles for Mn < 40 kg mol(-1) and the behavior of a soft elastic material was observed (G'≪G'' and G'∼ω(0)). For higher Mn materials, the filaments were randomly oriented and the polymers displayed a crossover towards viscous behavior although terminal relaxation was not reached in the experimental frequency window. All these materials show, however, similar adhesive properties characterized by a cohesive mode of failure and low debonding energies (Wadh < 40 J m(-2) for a debonding speed of 100 μm s(-1)). The debonding mechanisms observed during the adhesion tests have been investigated in detail with an Image tools analysis developed by our group. The measure of the projected area covered by cavities growing in the adhesive layer during debonding can be used to estimate the true stress in the walls of the cavities and thus to characterize the in situ large strain deformation of the thin layer during the adhesion test itself. This analysis revealed in particular that the PnBA3U materials with Mn < 40 kg mol(-1

  11. [Retention of adhesive bridges].

    PubMed

    Raes, F; De Boever, J

    1990-01-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. To ensure an adequate retention over a number of years different factors have to be considered. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin (Panavia Ex) are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rets, interocclusal clearance of 0.4 mm and cingulum stops is equally important. Care should be taken not to remove all the enamel in the cervical region in preparing a mini chamfer. Including more teeth in the design does not necessarily lead to an improved retention. Teeth with a different mobility should not be included in the same bridge. Besides the material and technical aspects, the whole clinical procedure needs much attention. Only an exact impression, a precise model and a reliable casting technique will provide a metal frame with an optimal marginal adaptation and a close fit. The retention does not depend on one single factor but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 90% can be obtained. PMID:2077574

  12. 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

    2016-04-01

    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. PMID:26953827

  13. Seafood delicacy makes great adhesive

    ScienceCinema

    Idaho National Laboratory - Frank Roberto, Heather Silverman

    2010-01-08

    Technology from Mother Nature is often hard to beat, so Idaho National Laboratory scientistsgenetically analyzed the adhesive proteins produced by blue mussels, a seafood delicacy. Afterobtaining full-length DNA sequences encoding these proteins, reprod

  14. Seafood delicacy makes great adhesive

    SciTech Connect

    Idaho National Laboratory - Frank Roberto, Heather Silverman

    2008-03-26

    Technology from Mother Nature is often hard to beat, so Idaho National Laboratory scientistsgenetically analyzed the adhesive proteins produced by blue mussels, a seafood delicacy. Afterobtaining full-length DNA sequences encoding these proteins, reprod

  15. Cardiopulmonary monitoring in intra-abdominal hypertension.

    PubMed

    Malbrain, Manu L N G; Ameloot, Koen; Gillebert, Carl; Cheatham, Michael L

    2011-07-01

    Cardiopulmonary dysfunction and failure are commonly encountered in the patient with intra-abdominal hypertension (IAH) or abdominal compartment syndrome. Accurate assessment and optimization of preload, contractility, and afterload in conjunction with appropriate goal-directed resuscitation and assessment of fluid responsiveness are essential to restore end-organ perfusion. In patients with IAH, the traditional "barometric" preload indicators such as pulmonary artery occlusion pressure and central venous pressure are erroneously increased. Volumetric monitoring techniques have been proven to be superior in directing the appropriate resuscitation together with targeted abdominal perfusion pressure. If such limitations are not recognized, misinterpretation of the patient's cardiac status is likely, resulting in inappropriate and potentially detrimental therapy. IAH also markedly affects the mechanical properties of the chest wall and consequently also the respiratory function. Altered mechanical properties of the chest wall may limit ventilation, influence the work of breathing, affect the interaction between the respiratory muscles, hasten the development of respiratory failure, and interfere with gas exchange. Pulmonary monitoring is important to understand the relationships between intra-abdominal pressure and chest wall mechanics and the impact of IAH on ventilator-induced lung injury, lung distention, recruitment, and lung edema. PMID:21944448

  16. Intra-abdominal sepsis after hepatic resection.

    PubMed Central

    Pace, R F; Blenkharn, J I; Edwards, W J; Orloff, M; Blumgart, L H; Benjamin, I S

    1989-01-01

    One hundred and thirty hepatic resections performed over an 8-year period were reviewed for evidence of postoperative intra-abdominal sepsis. Of 126 patients who survived for more than 24 hours after operation, 36 developed culture positive intra-abdominal collections (28.6%). Significant independent variables associated with the development of intra-abdominal sepsis were diagnoses of trauma or cholangiocarcinoma, and the need for reoperation to control hemorrhage during the postoperative period. Before 1984, infected fluid collections were treated predominantly by operative drainage, but this has largely been replaced by percutaneous methods, which have proven effective in most cases. Eighteen (50%) of the infections were caused by a mixed bacterial culture, with Streptococcus faecalis, Staphylococcus epidermidis, Staphylococcus aureus and Escherichia coli being the most common isolates. Six patients with clinical signs of sepsis had a sterile fluid collection drained with complete relief of symptoms. This review suggests that intra-abdominal sepsis is a frequent complication after hepatic resection, and can often be managed successfully by nonoperative percutaneous drainage. PMID:2493775

  17. Acute abdominal complications following hip surgery.

    PubMed

    Deleanu, B; Prejbeanu, R; Vermesan, D; Haragus, H; Icma, I; Predescu, V

    2014-01-01

    Hip surgeries are some of the most common and successful orthopedic procedures. Although rarely, abdominal complications do occur and are associated with unfavorable outcomes.We aimed to identify and describe the severe abdominal complications that appear in patients under-going elective or traumatic hip surgery. A four year retrospective electronic database research identified 408 elective primary hip replacements,51 hip revisions and 1040 intra and extracapsular proximal femur fractures. Out of these, three males and 4 females between 64 - 84 years old were identified to have developed acute abdominal complications: perforated acute ulcer (3),acute cholecystitis (2), volvulus (1), toxic megacolon with peritonitis (1) and acute colonic pseudo-obstruction (1).Complications debuted 3 - 10 days after index orthopedic surgery. Acute perioperative abdominal complications are rarely encountered during orthopedic surgery. When these do occur, they do so almost exclusively in patients with hippathology, comorbidities and most often lead to life threatening situations. We thus emphasize the need for early identification and appropriate management by both orthopedic and general surgery doctors in order to improve patient safety. PMID:24742414

  18. Abdominal injury due to child abuse.

    PubMed

    Barnes, Peter M; Norton, Catherine M; Dunstan, Frank D; Kemp, Alison M; Yates, David W; Sibert, Jonathan R

    Diagnosis of abuse in children with internal abdominal injury is difficult because of limited published work. We aimed to ascertain the incidence of abdominal injury due to abuse in children age 0-14 years. 20 children (identified via the British Paediatric Surveillance Unit) had abdominal injuries due to abuse and 164 (identified via the Trauma Audit and Research Network) had injuries to the abdomen due to accident (112 by road-traffic accidents, 52 by falls). 16 abused children were younger than 5 years. Incidence of abdominal injury due to abuse was 2.33 cases per million children per year (95% CI 1.43-3.78) in children younger than 5 years. Six abused children died. 11 abused children had an injury to the gut (ten small bowel) compared with five (all age >5 years) who were injured by a fall (relative risk 5.72 [95% CI 2.27-14.4]; p=0.0002). We have shown that small-bowel injuries can arise accidentally as a result of falls and road-traffic accidents but they are significantly more common in abused children. Therefore, injuries to the small bowel in young children need special consideration, particularly if a minor fall is the explanation. PMID:16023514

  19. Childhood functional abdominal pain: mechanisms and management.

    PubMed

    Korterink, Judith; Devanarayana, Niranga Manjuri; Rajindrajith, Shaman; Vlieger, Arine; Benninga, Marc A

    2015-03-01

    Chronic abdominal pain is one of the most common clinical syndromes encountered in day to day clinical paediatric practice. Although common, its definition is confusing, predisposing factors are poorly understood and the pathophysiological mechanisms are not clear. The prevailing viewpoint in the pathogenesis involves the inter-relationship between changes in hypersensitivity and altered motility, to which several risk factors have been linked. Making a diagnosis of functional abdominal pain can be a challenge, as it is unclear which further diagnostic tests are necessary to exclude an organic cause. Moreover, large, well-performed, high-quality clinical trials for effective agents are lacking, which undermines evidence-based treatment. This Review summarizes current knowledge regarding the epidemiology, pathophysiology, risk factors and diagnostic work-up of functional abdominal pain. Finally, management options for children with functional abdominal pain are discussed including medications, dietary interventions, probiotics and psychological and complementary therapies, to improve understanding and to maximize the quality of care for children with this condition. PMID:25666642

  20. Abdominal wall herniae and their underlying pathology

    PubMed Central

    Upchurch, Emma; Al-Akash, Musallam

    2016-01-01

    We describe a case of pseudomyxoma peritonei presenting as a strangulated inguinal hernia. We review the current literature regarding the incidence of underlying pathology in patients presenting with abdominal wall herniae and discuss the need for histological assessment of the hernia sac in selected patients. We highlight the importance of assessing for and being aware of significant underlying pathology in certain patients. PMID:26855074